A System to Provide Real-Time Collaborative Situational Awareness by Web Enabling a Distributed Sensor Network

NASA Technical Reports Server (NTRS)

Panangadan, Anand; Monacos, Steve; Burleigh, Scott; Joswig, Joseph; James, Mark; Chow, Edward

2012-01-01

In this paper, we describe the architecture of both the PATS and SAP systems and how these two systems interoperate with each other forming a unified capability for deploying intelligence in hostile environments with the objective of providing actionable situational awareness of individuals. The SAP system works in concert with the UICDS information sharing middleware to provide data fusion from multiple sources. UICDS can then publish the sensor data using the OGC's Web Mapping Service, Web Feature Service, and Sensor Observation Service standards. The system described in the paper is able to integrate a spatially distributed sensor system, operating without the benefit of the Web infrastructure, with a remote monitoring and control system that is equipped to take advantage of SWE.

Publication of sensor data in the long-term environmental monitoring infrastructure TERENO

NASA Astrophysics Data System (ADS)

Stender, V.; Schroeder, M.; Klump, J. F.

2014-12-01

Terrestrial Environmental Observatories (TERENO) is an interdisciplinary and long-term research project spanning an Earth observation network across Germany. It includes four test sites within Germany from the North German lowlands to the Bavarian Alps and is operated by six research centers of the Helmholtz Association. TERENO Northeast is one of the sub-observatories of TERENO and is operated by the German Research Centre for Geosciences GFZ in Potsdam. This observatory investigates geoecological processes in the northeastern lowland of Germany by collecting large amounts of environmentally relevant data. The success of long-term projects like TERENO depends on well-organized data management, data exchange between the partners involved and on the availability of the captured data. Data discovery and dissemination are facilitated not only through data portals of the regional TERENO observatories but also through a common spatial data infrastructure TEODOOR (TEreno Online Data repOsitORry). TEODOOR bundles the data, provided by the different web services of the single observatories, and provides tools for data discovery, visualization and data access. The TERENO Northeast data infrastructure integrates data from more than 200 instruments and makes data available through standard web services. TEODOOR accesses the OGC Sensor Web Enablement (SWE) interfaces offered by the regional observatories. In addition to the SWE interface, TERENO Northeast also publishes time series of environmental sensor data through the online research data publication platform DataCite. The metadata required by DataCite are created in an automated process by extracting information from the SWE SensorML to create ISO 19115 compliant metadata. The GFZ data management tool kit panMetaDocs is used to register Digital Object Identifiers (DOI) and preserve file based datasets. In addition to DOI, the International Geo Sample Numbers (IGSN) is used to uniquely identify research specimens.

A semantically rich and standardised approach enhancing discovery of sensor data and metadata

NASA Astrophysics Data System (ADS)

Kokkinaki, Alexandra; Buck, Justin; Darroch, Louise

2016-04-01

The marine environment plays an essential role in the earth's climate. To enhance the ability to monitor the health of this important system, innovative sensors are being produced and combined with state of the art sensor technology. As the number of sensors deployed is continually increasing,, it is a challenge for data users to find the data that meet their specific needs. Furthermore, users need to integrate diverse ocean datasets originating from the same or even different systems. Standards provide a solution to the above mentioned challenges. The Open Geospatial Consortium (OGC) has created Sensor Web Enablement (SWE) standards that enable different sensor networks to establish syntactic interoperability. When combined with widely accepted controlled vocabularies, they become semantically rich and semantic interoperability is achievable. In addition, Linked Data is the recommended best practice for exposing, sharing and connecting information on the Semantic Web using Uniform Resource Identifiers (URIs), Resource Description Framework (RDF) and RDF Query Language (SPARQL). As part of the EU-funded SenseOCEAN project, the British Oceanographic Data Centre (BODC) is working on the standardisation of sensor metadata enabling 'plug and play' sensor integration. Our approach combines standards, controlled vocabularies and persistent URIs to publish sensor descriptions, their data and associated metadata as 5 star Linked Data and OGC SWE (SensorML, Observations & Measurements) standard. Thus sensors become readily discoverable, accessible and useable via the web. Content and context based searching is also enabled since sensors descriptions are understood by machines. Additionally, sensor data can be combined with other sensor or Linked Data datasets to form knowledge. This presentation will describe the work done in BODC to achieve syntactic and semantic interoperability in the sensor domain. It will illustrate the reuse and extension of the Semantic Sensor Network (SSN) ontology to Linked Sensor Ontology (LSO) and the steps taken to combine OGC SWE with the Linked Data approach through alignment and embodiment of other ontologies. It will then explain how data and models were annotated with controlled vocabularies to establish unambiguous semantics and interconnect them with data from different sources. Finally, it will introduce the RDF triple store where the sensor descriptions and metadata are stored and can be queried through the standard query language SPARQL. Providing different flavours of machine readable interpretations of sensors, sensor data and metadata enhances discoverability but most importantly allows seamless aggregation of information from different networks that will finally produce knowledge.

Incorporating Quality Control Information in the Sensor Web

NASA Astrophysics Data System (ADS)

Devaraju, Anusuriya; Kunkel, Ralf; Bogena, Heye

2013-04-01

The rapid development of sensing technologies had led to the creation of large amounts of heterogeneous environmental observations. The Sensor Web provides a wider access to sensors and observations via common protocols and specifications. Observations typically go through several levels of quality control, and aggregation before they are made available to end-users. Raw data are usually inspected, and related quality flags are assigned. Data are gap-filled, and errors are removed. New data series may also be derived from one or more corrected data sets. Until now, it is unclear how these kinds of information can be captured in the Sensor Web Enablement (SWE) framework. Apart from the quality measures (e.g., accuracy, precision, tolerance, or confidence), the levels of observational series, the changes applied, and the methods involved must be specified. It is important that this kind of quality control information is well described and communicated to end-users to allow for a better usage and interpretation of data products. In this paper, we describe how quality control information can be incorporated into the SWE framework. Concerning this, first, we introduce the TERENO (TERrestrial ENvironmental Observatories), an initiative funded by the large research infrastructure program of the Helmholtz Association in Germany. The main goal of the initiative is to facilitate the study of long-term effects of climate and land use changes. The TERENO Online Data RepOsitORry (TEODOOR) is a software infrastructure that supports acquisition, provision, and management of observations within TERENO via SWE specifications and several other OGC web services. Next, we specify changes made to the existing observational data model to incorporate quality control information. Here, we describe the underlying TERENO data policy in terms of provision and maintenance issues. We present data levels, and their implementation within TEODOOR. The data levels are adapted from those used by other similar systems such as CUAHSI, EarthScope and WMO. Finally, we outline recommendations for future work.

GITEWS, an extensible and open integration platform for manifold sensor systems and processing components based on Sensor Web Enablement and the principles of Service Oriented Architectures

NASA Astrophysics Data System (ADS)

Haener, Rainer; Waechter, Joachim; Fleischer, Jens; Herrnkind, Stefan; Schwarting, Herrmann

2010-05-01

The German Indonesian Tsunami Early Warning System (GITEWS) is a multifaceted system consisting of various sensor types like seismometers, sea level sensors or GPS stations, and processing components, all with their own system behavior and proprietary data structure. To operate a warning chain, beginning from measurements scaling up to warning products, all components have to interact in a correct way, both syntactically and semantically. Designing the system great emphasis was laid on conformity to the Sensor Web Enablement (SWE) specification by the Open Geospatial Consortium (OGC). The technical infrastructure, the so called Tsunami Service Bus (TSB) follows the blueprint of Service Oriented Architectures (SOA). The TSB is an integration concept (SWE) where functionality (observe, task, notify, alert, and process) is grouped around business processes (Monitoring, Decision Support, Sensor Management) and packaged as interoperable services (SAS, SOS, SPS, WNS). The benefits of using a flexible architecture together with SWE lead to an open integration platform: • accessing and controlling heterogeneous sensors in a uniform way (Functional Integration) • assigns functionality to distinct services (Separation of Concerns) • allows resilient relationship between systems (Loose Coupling) • integrates services so that they can be accessed from everywhere (Location Transparency) • enables infrastructures which integrate heterogeneous applications (Encapsulation) • allows combination of services (Orchestration) and data exchange within business processes Warning systems will evolve over time: New sensor types might be added, old sensors will be replaced and processing components will be improved. From a collection of few basic services it shall be possible to compose more complex functionality essential for specific warning systems. Given these requirements a flexible infrastructure is a prerequisite for sustainable systems and their architecture must be tailored for evolution. The use of well-known techniques and widely used open source software implementing industrial standards reduces the impact of service modifications allowing the evolution of a system as a whole. GITEWS implemented a solution to feed sensor raw data from any (remote) system into the infrastructure. Specific dispatchers enable plugging in sensor-type specific processing without changing the architecture. Client components don't need to be adjusted if new sensor-types or individuals are added to the system, because they access them via standardized services. One of the outstanding features of service-oriented architectures is the possibility to compose new services from existing ones. The so called orchestration, allows the definition of new warning processes which can be adapted easily to new requirements. This approach has following advantages: • With implementing SWE it is possible to establish the "detection" and integration of sensors via the internet. Thus a system of systems combining early warning functionality at different levels of detail is feasible. • Any institution could add both its own components as well as components from third parties if they are developed in conformance to SOA principles. In a federation an institution keeps the ownership of its data and decides which data are provided by a service and when. • A system can be deployed at minor costs as a core for own development at any institution and thus enabling autonomous early warning- or monitoring systems. The presentation covers both design and various instantiations (live demonstration) of the GITEWS architecture. Experiences concerning the design and complexity of SWE will be addressed in detail. A substantial amount of attention is laid on the techniques and methods of extending the architecture, adapting proprietary components to SWE services and encoding, and their orchestration in high level workflows and processes. Furthermore the potential of the architecture concerning adaptive behavior, collaboration across boundaries and semantic interoperability will be addressed.

Automatic publishing ISO 19115 metadata with PanMetaDocs using SensorML information

NASA Astrophysics Data System (ADS)

Stender, Vivien; Ulbricht, Damian; Schroeder, Matthias; Klump, Jens

2014-05-01

Terrestrial Environmental Observatories (TERENO) is an interdisciplinary and long-term research project spanning an Earth observation network across Germany. It includes four test sites within Germany from the North German lowlands to the Bavarian Alps and is operated by six research centers of the Helmholtz Association. The contribution by the participating research centers is organized as regional observatories. A challenge for TERENO and its observatories is to integrate all aspects of data management, data workflows, data modeling and visualizations into the design of a monitoring infrastructure. TERENO Northeast is one of the sub-observatories of TERENO and is operated by the German Research Centre for Geosciences (GFZ) in Potsdam. This observatory investigates geoecological processes in the northeastern lowland of Germany by collecting large amounts of environmentally relevant data. The success of long-term projects like TERENO depends on well-organized data management, data exchange between the partners involved and on the availability of the captured data. Data discovery and dissemination are facilitated not only through data portals of the regional TERENO observatories but also through a common spatial data infrastructure TEODOOR (TEreno Online Data repOsitORry). TEODOOR bundles the data, provided by the different web services of the single observatories, and provides tools for data discovery, visualization and data access. The TERENO Northeast data infrastructure integrates data from more than 200 instruments and makes data available through standard web services. Geographic sensor information and services are described using the ISO 19115 metadata schema. TEODOOR accesses the OGC Sensor Web Enablement (SWE) interfaces offered by the regional observatories. In addition to the SWE interface, TERENO Northeast also published data through DataCite. The necessary metadata are created in an automated process by extracting information from the SWE SensorML to create ISO 19115 compliant metadata. The resulting metadata file is stored in the GFZ Potsdam data infrastructure. The publishing workflow for file based research datasets at GFZ Potsdam is based on the eSciDoc infrastructure, using PanMetaDocs (PMD) as the graphical user interface. PMD is a collaborative, metadata based data and information exchange platform [1]. Besides SWE, metadata are also syndicated by PMD through an OAI-PMH interface. In addition, metadata from other observatories, projects or sensors in TERENO can be accessed through the TERENO Northeast data portal. [1] http://meetingorganizer.copernicus.org/EGU2012/EGU2012-7058-2.pdf

Autonomous Mission Operations for Sensor Webs

NASA Astrophysics Data System (ADS)

Underbrink, A.; Witt, K.; Stanley, J.; Mandl, D.

2008-12-01

We present interim results of a 2005 ROSES AIST project entitled, "Using Intelligent Agents to Form a Sensor Web for Autonomous Mission Operations", or SWAMO. The goal of the SWAMO project is to shift the control of spacecraft missions from a ground-based, centrally controlled architecture to a collaborative, distributed set of intelligent agents. The network of intelligent agents intends to reduce management requirements by utilizing model-based system prediction and autonomic model/agent collaboration. SWAMO agents are distributed throughout the Sensor Web environment, which may include multiple spacecraft, aircraft, ground systems, and ocean systems, as well as manned operations centers. The agents monitor and manage sensor platforms, Earth sensing systems, and Earth sensing models and processes. The SWAMO agents form a Sensor Web of agents via peer-to-peer coordination. Some of the intelligent agents are mobile and able to traverse between on-orbit and ground-based systems. Other agents in the network are responsible for encapsulating system models to perform prediction of future behavior of the modeled subsystems and components to which they are assigned. The software agents use semantic web technologies to enable improved information sharing among the operational entities of the Sensor Web. The semantics include ontological conceptualizations of the Sensor Web environment, plus conceptualizations of the SWAMO agents themselves. By conceptualizations of the agents, we mean knowledge of their state, operational capabilities, current operational capacities, Web Service search and discovery results, agent collaboration rules, etc. The need for ontological conceptualizations over the agents is to enable autonomous and autonomic operations of the Sensor Web. The SWAMO ontology enables automated decision making and responses to the dynamic Sensor Web environment and to end user science requests. The current ontology is compatible with Open Geospatial Consortium (OGC) Sensor Web Enablement (SWE) Sensor Model Language (SensorML) concepts and structures. The agents are currently deployed on the U.S. Naval Academy MidSTAR-1 satellite and are actively managing the power subsystem on-orbit without the need for human intervention.

Publication of sensor data in the long-term environmental sub-observatory TERENO Northeast

NASA Astrophysics Data System (ADS)

Stender, Vivien; Ulbricht, Damian; Klump, Jens

2017-04-01

Terrestrial Environmental Observatories (TERENO) is an interdisciplinary and long-term research project spanning an Earth observation network across Germany. It includes four test sites within Germany from the North German lowlands to the Bavarian Alps and is operated by six research centers of the Helmholtz Association. TERENO Northeast is one of the sub-observatories of TERENO and is operated by the German Research Centre for Geosciences GFZ in Potsdam. This observatory investigates geoecological processes in the northeastern lowland of Germany by collecting large amounts of environmentally relevant data. The success of long-term projects like TERENO depends on well-organized data management, data exchange between the partners involved and on the availability of the captured data. Data discovery and dissemination are facilitated not only through data portals of the regional TERENO observatories but also through a common spatial data infrastructure TEODOOR (TEreno Online Data repOsitORry). TEODOOR bundles the data provided by the different web services of the single observatories and provides tools for data discovery, visualization and data access. The TERENO Northeast data infrastructure integrates data from more than 200 instruments and makes data available through standard web services. TEODOOR accesses the OGC Sensor Web Enablement (SWE) interfaces offered by the regional observatories. In addition to the SWE interface, TERENO Northeast also publishes time series of environmental sensor data through the DOI registration service at GFZ Potsdam. This service uses the DataCite infrastructure to make research data citable and is able to keep and disseminate metadata popular to the geosciences [1]. The metadata required by DataCite are created in an automated process by extracting information from the SWE SensorML metadata. The GFZ data management tool kit panMetaDocs is used to manage and archive file based datasets and to register Digital Object Identifiers (DOI) for published data. In this presentation we will report on current advances in publication of time series data from environmental sensor networks. [1]http://doidb.wdc-terra.org/oaip/oai?verb=ListRecords&metadataPrefix=iso19139&set=DOIDB.TERENO

A Web 2.0 and OGC Standards Enabled Sensor Web Architecture for Global Earth Observing System of Systems

NASA Technical Reports Server (NTRS)

Mandl, Daniel; Unger, Stephen; Ames, Troy; Frye, Stuart; Chien, Steve; Cappelaere, Pat; Tran, Danny; Derezinski, Linda; Paules, Granville

2007-01-01

This paper will describe the progress of a 3 year research award from the NASA Earth Science Technology Office (ESTO) that began October 1, 2006, in response to a NASA Announcement of Research Opportunity on the topic of sensor webs. The key goal of this research is to prototype an interoperable sensor architecture that will enable interoperability between a heterogeneous set of space-based, Unmanned Aerial System (UAS)-based and ground based sensors. Among the key capabilities being pursued is the ability to automatically discover and task the sensors via the Internet and to automatically discover and assemble the necessary science processing algorithms into workflows in order to transform the sensor data into valuable science products. Our first set of sensor web demonstrations will prototype science products useful in managing wildfires and will use such assets as the Earth Observing 1 spacecraft, managed out of NASA/GSFC, a UASbased instrument, managed out of Ames and some automated ground weather stations, managed by the Forest Service. Also, we are collaborating with some of the other ESTO awardees to expand this demonstration and create synergy between our research efforts. Finally, we are making use of Open Geospatial Consortium (OGC) Sensor Web Enablement (SWE) suite of standards and some Web 2.0 capabilities to Beverage emerging technologies and standards. This research will demonstrate and validate a path for rapid, low cost sensor integration, which is not tied to a particular system, and thus be able to absorb new assets in an easily evolvable, coordinated manner. This in turn will help to facilitate the United States contribution to the Global Earth Observation System of Systems (GEOSS), as agreed by the U.S. and 60 other countries at the third Earth Observation Summit held in February of 2005.

Facilitating Stewardship of scientific data through standards based workflows

NASA Astrophysics Data System (ADS)

Bastrakova, I.; Kemp, C.; Potter, A. K.

2013-12-01

There are main suites of standards that can be used to define the fundamental scientific methodology of data, methods and results. These are firstly Metadata standards to enable discovery of the data (ISO 19115), secondly the Sensor Web Enablement (SWE) suite of standards that include the O&M and SensorML standards and thirdly Ontology that provide vocabularies to define the scientific concepts and relationships between these concepts. All three types of standards have to be utilised by the practicing scientist to ensure that those who ultimately have to steward the data stewards to ensure that the data can be preserved curated and reused and repurposed. Additional benefits of this approach include transparency of scientific processes from the data acquisition to creation of scientific concepts and models, and provision of context to inform data use. Collecting and recording metadata is the first step in scientific data flow. The primary role of metadata is to provide details of geographic extent, availability and high-level description of data suitable for its initial discovery through common search engines. The SWE suite provides standardised patterns to describe observations and measurements taken for these data, capture detailed information about observation or analytical methods, used instruments and define quality determinations. This information standardises browsing capability over discrete data types. The standardised patterns of the SWE standards simplify aggregation of observation and measurement data enabling scientists to transfer disintegrated data to scientific concepts. The first two steps provide a necessary basis for the reasoning about concepts of ';pure' science, building relationship between concepts of different domains (linked-data), and identifying domain classification and vocabularies. Geoscience Australia is re-examining its marine data flows, including metadata requirements and business processes, to achieve a clearer link between scientific data acquisition and analysis requirements and effective interoperable data management and delivery. This includes participating in national and international dialogue on development of standards, embedding data management activities in business processes, and developing scientific staff as effective data stewards. Similar approach is applied to the geophysical data. By ensuring the geophysical datasets at GA strictly follow metadata and industry standards we are able to implement a provenance based workflow where the data is easily discoverable, geophysical processing can be applied to it and results can be stored. The provenance based workflow enables metadata records for the results to be produced automatically from the input dataset metadata.

THE TSUNAMI SERVICE BUS, AN INTEGRATION PLATFORM FOR HETEROGENEOUS SENSOR SYSTEMS

NASA Astrophysics Data System (ADS)

Fleischer, J.; Häner, R.; Herrnkind, S.; Kriegel, U.; Schwarting, H.; Wächter, J.

2009-12-01

The Tsunami Service Bus (TSB) is the sensor integration platform of the German Indonesian Tsunami Early Warning System (GITEWS) [1]. The primary goal of GITEWS is to deliver reliable tsunami warnings as fast as possible. This is achieved on basis of various sensor systems like seismometers, ocean instrumentation, and GPS stations, all providing fundamental data to support prediction of tsunami wave propagation by the GITEWS warning center. However, all these sensors come with their own proprietary data formats and specific behavior. Also new sensor types might be added, old sensors will be replaced. To keep GITEWS flexible the TSB was developed in order to access and control sensors in a uniform way. To meet these requirements the TSB follows the architectural blueprint of a Service Oriented Architecture (SOA). The integration platform implements dedicated services communicating via a service infrastructure. The functionality required for early warnings is provided by loosely coupled services replacing the "hard-wired" coupling at data level. Changes in the sensor specification are confined to the data level without affecting the warning center. Great emphasis was laid on following the Sensor Web Enablement (SWE) standard [2], specified by the Open Geospatial Consortium (OGC) [3]. As a result the full functionality needed in GITEWS could be achieved by implementing the four SWE services: The Sensor Observation Service for retrieving sensor measurements, the Sensor Alert Service in order to deliver sensor alerts, the Sensor Planning Service for tasking sensors, and the Web Notification Service for conduction messages to various media channels. Beyond these services the TSB also follows SWE Observation & Measurements specifications (O&M) for data encoding and Sensor Model Language (SensorML) for meta information. Moreover, accessing sensors via the TSB is not restricted to GITEWS. Multiple instances of the TSB can be composed to realize federate warning system. Beside the already operating TSB at the BMKG warning center [4], two other organizations in Indonesia ([5], [6]) consider using the TSB, making their data centers available to GITEWS. The presentation takes a look at the concepts and implementation and reflects the usefulness of the mentioned standards. REFERENCES [1] GITEWS is a project of the German Federal Government to aid the recon¬struction of the tsunami-prone region of the Indian Ocean, http://www.gitews.org/ [2] SWE, www.opengeospatial.org/projects/groups/sensorweb [3] OGC, www.opengeospatial.org [4] Meteorological and Geophysical Agency of Indonesia (BMKG), www.bmg.go.id [5] National Coordinating Agency for Surveys and Mapping (BAKOSURTANAL), www.bakosurtanal.go.id [6] Agency for the Assessment & Application of Technology (BPPT), www.bppt.go.id

Autonomous Sensorweb Operations for Integrated Space, In-Situ Monitoring of Volcanic Activity

NASA Technical Reports Server (NTRS)

Chien, Steve A.; Doubleday, Joshua; Kedar, Sharon; Davies, Ashley G.; Lahusen, Richard; Song, Wenzhan; Shirazi, Behrooz; Mandl, Daniel; Frye, Stuart

2010-01-01

We have deployed and demonstrated operations of an integrated space in-situ sensorweb for monitoring volcanic activity. This sensorweb includes a network of ground sensors deployed to the Mount Saint Helens volcano as well as the Earth Observing One spacecraft. The ground operations and space operations are interlinked in that ground-based intelligent event detections can cause the space segment to acquire additional data via observation requests and space-based data acquisitions (thermal imagery) can trigger reconfigurations of the ground network to allocate increased bandwidth to areas of the network best situated to observe the activity. The space-based operations are enabled by an automated mission planning and tasking capability which utilizes several Opengeospatial Consortium (OGC) Sensorweb Enablement (SWE) standards which enable acquiring data, alerts, and tasking using web services. The ground-based segment also supports similar protocols to enable seamless tasking and data delivery. The space-based segment also supports onboard development of data products (thermal summary images indicating areas of activity, quicklook context images, and thermal activity alerts). These onboard developed products have reduced data volume (compared to the complete images) which enables them to be transmitted to the ground more rapidly in engineering channels.

Implementing CUAHSI and SWE observation data models in the long-term monitoring infrastructure TERENO

NASA Astrophysics Data System (ADS)

Klump, J. F.; Stender, V.; Schroeder, M.

2013-12-01

Terrestrial Environmental Observatories (TERENO) is an interdisciplinary and long-term research project spanning an Earth observation network across Germany. It includes four test sites within Germany from the North German lowlands to the Bavarian Alps and is operated by six research centers of the Helmholtz Association. The contribution by the participating research centers is organized as regional observatories. The challenge for TERENO and its observatories is to integrate all aspects of data management, data workflows, data modeling and visualizations into the design of a monitoring infrastructure. TERENO Northeast is one of the sub-observatories of TERENO and is operated by the German Research Centre for Geosciences GFZ in Potsdam. This observatory investigates geoecological processes in the northeastern lowland of Germany by collecting large amounts of environmentally relevant data. The success of long-term projects like TERENO depends on well-organized data management, data exchange between the partners involved and on the availability of the captured data. Data discovery and dissemination are facilitated not only through data portals of the regional TERENO observatories but also through a common spatial data infrastructure TEODOOR. TEODOOR bundles the data, provided by the different web services of the single observatories, and provides tools for data discovery, visualization and data access. The TERENO Northeast data infrastructure integrates data from more than 200 instruments and makes the data available through standard web services. Data are stored following the CUAHSI observation data model in combination with the 52° North Sensor Observation Service data model. The data model was implemented using the PostgreSQL/PostGIS DBMS. Especially in a long-term project, such as TERENO, care has to be taken in the data model. We chose to adopt the CUAHSI observational data model because it is designed to store observations and descriptive information (metadata) about the data values in combination with information about the sensor systems. Also the CUAHSI model is supported by a large and active international user community. The 52° North SOS data model can be modeled as a sub-set of the CUHASI data model. In our implementation the 52° North SWE data model is implemented as database views of the CUHASI model to avoid redundant data storage. An essential aspect in TERENO Northeast is the use of standard OGS web services to facilitate data exchange and interoperability. A uniform treatment of sensor data can be realized through OGC Sensor Web Enablement (SWE) which makes a number of standards and interface definitions available: Observation & Measurement (O&M) model for the description of observations and measurements, Sensor Model Language (SensorML) for the description of sensor systems, Sensor Observation Service (SOS) for obtaining sensor observations, Sensor Planning Service (SPS) for tasking sensors, Web Notification Service (WNS) for asynchronous dialogues and Sensor Alert Service (SAS) for sending alerts.

Performance of shear wave elastography for differentiation of benign and malignant solid breast masses.

PubMed

Li, Guiling; Li, De-Wei; Fang, Yu-Xiao; Song, Yi-Jiang; Deng, Zhu-Jun; Gao, Jian; Xie, Yan; Yin, Tian-Sheng; Ying, Li; Tang, Kai-Fu

2013-01-01

To perform a meta-analysis assessing the ability of shear wave elastography (SWE) to identify malignant breast masses. PubMed, the Cochrane Library, and the ISI Web of Knowledge were searched for studies evaluating the accuracy of SWE for identifying malignant breast masses. The diagnostic accuracy of SWE was evaluated according to sensitivity, specificity, and hierarchical summary receiver operating characteristic (HSROC) curves. An analysis was also performed according to the SWE mode used: supersonic shear imaging (SSI) and the acoustic radiation force impulse (ARFI) technique. The clinical utility of SWE for identifying malignant breast masses was evaluated using analysis of Fagan plot. A total of 9 studies, including 1888 women and 2000 breast masses, were analyzed. Summary sensitivities and specificities were 0.91 (95% confidence interval [CI], 0.88-0.94) and 0.82 (95% CI, 0.75-0.87) by SSI and 0.89 (95% CI, 0.81-0.94) and 0.91 (95% CI, 0.84-0.95) by ARFI, respectively. The HSROCs for SSI and ARFI were 0.92 (95% CI, 0.90-0.94) and 0.96 (95% CI, 0.93-0.97), respectively. SSI and ARFI were both very informative, with probabilities of 83% and 91%, respectively, for correctly differentiating between benign and malignant breast masses following a "positive" measurement (over the threshold value) and probabilities of disease as low as 10% and 11%, respectively, following a "negative" measurement (below the threshold value) when the pre-test probability was 50%. SWE could be used as a good identification tool for the classification of breast masses.

Sharing Human-Generated Observations by Integrating HMI and the Semantic Sensor Web

PubMed Central

Sigüenza, Álvaro; Díaz-Pardo, David; Bernat, Jesús; Vancea, Vasile; Blanco, José Luis; Conejero, David; Gómez, Luis Hernández

2012-01-01

Current “Internet of Things” concepts point to a future where connected objects gather meaningful information about their environment and share it with other objects and people. In particular, objects embedding Human Machine Interaction (HMI), such as mobile devices and, increasingly, connected vehicles, home appliances, urban interactive infrastructures, etc., may not only be conceived as sources of sensor information, but, through interaction with their users, they can also produce highly valuable context-aware human-generated observations. We believe that the great promise offered by combining and sharing all of the different sources of information available can be realized through the integration of HMI and Semantic Sensor Web technologies. This paper presents a technological framework that harmonizes two of the most influential HMI and Sensor Web initiatives: the W3C's Multimodal Architecture and Interfaces (MMI) and the Open Geospatial Consortium (OGC) Sensor Web Enablement (SWE) with its semantic extension, respectively. Although the proposed framework is general enough to be applied in a variety of connected objects integrating HMI, a particular development is presented for a connected car scenario where drivers' observations about the traffic or their environment are shared across the Semantic Sensor Web. For implementation and evaluation purposes an on-board OSGi (Open Services Gateway Initiative) architecture was built, integrating several available HMI, Sensor Web and Semantic Web technologies. A technical performance test and a conceptual validation of the scenario with potential users are reported, with results suggesting the approach is sound. PMID:22778643

Sharing human-generated observations by integrating HMI and the Semantic Sensor Web.

PubMed

Sigüenza, Alvaro; Díaz-Pardo, David; Bernat, Jesús; Vancea, Vasile; Blanco, José Luis; Conejero, David; Gómez, Luis Hernández

2012-01-01

Current "Internet of Things" concepts point to a future where connected objects gather meaningful information about their environment and share it with other objects and people. In particular, objects embedding Human Machine Interaction (HMI), such as mobile devices and, increasingly, connected vehicles, home appliances, urban interactive infrastructures, etc., may not only be conceived as sources of sensor information, but, through interaction with their users, they can also produce highly valuable context-aware human-generated observations. We believe that the great promise offered by combining and sharing all of the different sources of information available can be realized through the integration of HMI and Semantic Sensor Web technologies. This paper presents a technological framework that harmonizes two of the most influential HMI and Sensor Web initiatives: the W3C's Multimodal Architecture and Interfaces (MMI) and the Open Geospatial Consortium (OGC) Sensor Web Enablement (SWE) with its semantic extension, respectively. Although the proposed framework is general enough to be applied in a variety of connected objects integrating HMI, a particular development is presented for a connected car scenario where drivers' observations about the traffic or their environment are shared across the Semantic Sensor Web. For implementation and evaluation purposes an on-board OSGi (Open Services Gateway Initiative) architecture was built, integrating several available HMI, Sensor Web and Semantic Web technologies. A technical performance test and a conceptual validation of the scenario with potential users are reported, with results suggesting the approach is sound.

Performance of Shear Wave Elastography for Differentiation of Benign and Malignant Solid Breast Masses

PubMed Central

Song, Yi-Jiang; Deng, Zhu-Jun; Gao, Jian; Xie, Yan; Yin, Tian-Sheng; Ying, Li; Tang, Kai-Fu

2013-01-01

Objectives To perform a meta-analysis assessing the ability of shear wave elastography (SWE) to identify malignant breast masses. Methods PubMed, the Cochrane Library, and the ISI Web of Knowledge were searched for studies evaluating the accuracy of SWE for identifying malignant breast masses. The diagnostic accuracy of SWE was evaluated according to sensitivity, specificity, and hierarchical summary receiver operating characteristic (HSROC) curves. An analysis was also performed according to the SWE mode used: supersonic shear imaging (SSI) and the acoustic radiation force impulse (ARFI) technique. The clinical utility of SWE for identifying malignant breast masses was evaluated using analysis of Fagan plot. Results A total of 9 studies, including 1888 women and 2000 breast masses, were analyzed. Summary sensitivities and specificities were 0.91 (95% confidence interval [CI], 0.88–0.94) and 0.82 (95% CI, 0.75–0.87) by SSI and 0.89 (95% CI, 0.81–0.94) and 0.91 (95% CI, 0.84–0.95) by ARFI, respectively. The HSROCs for SSI and ARFI were 0.92 (95% CI, 0.90–0.94) and 0.96 (95% CI, 0.93–0.97), respectively. SSI and ARFI were both very informative, with probabilities of 83% and 91%, respectively, for correctly differentiating between benign and malignant breast masses following a “positive” measurement (over the threshold value) and probabilities of disease as low as 10% and 11%, respectively, following a “negative” measurement (below the threshold value) when the pre-test probability was 50%. Conclusions SWE could be used as a good identification tool for the classification of breast masses. PMID:24204613

Integration of Grid and Sensor Web for Flood Monitoring and Risk Assessment from Heterogeneous Data

NASA Astrophysics Data System (ADS)

Kussul, Nataliia; Skakun, Sergii; Shelestov, Andrii

2013-04-01

Over last decades we have witnessed the upward global trend in natural disaster occurrence. Hydrological and meteorological disasters such as floods are the main contributors to this pattern. In recent years flood management has shifted from protection against floods to managing the risks of floods (the European Flood risk directive). In order to enable operational flood monitoring and assessment of flood risk, it is required to provide an infrastructure with standardized interfaces and services. Grid and Sensor Web can meet these requirements. In this paper we present a general approach to flood monitoring and risk assessment based on heterogeneous geospatial data acquired from multiple sources. To enable operational flood risk assessment integration of Grid and Sensor Web approaches is proposed [1]. Grid represents a distributed environment that integrates heterogeneous computing and storage resources administrated by multiple organizations. SensorWeb is an emerging paradigm for integrating heterogeneous satellite and in situ sensors and data systems into a common informational infrastructure that produces products on demand. The basic Sensor Web functionality includes sensor discovery, triggering events by observed or predicted conditions, remote data access and processing capabilities to generate and deliver data products. Sensor Web is governed by the set of standards, called Sensor Web Enablement (SWE), developed by the Open Geospatial Consortium (OGC). Different practical issues regarding integration of Sensor Web with Grids are discussed in the study. We show how the Sensor Web can benefit from using Grids and vice versa. For example, Sensor Web services such as SOS, SPS and SAS can benefit from the integration with the Grid platform like Globus Toolkit. The proposed approach is implemented within the Sensor Web framework for flood monitoring and risk assessment, and a case-study of exploiting this framework, namely the Namibia SensorWeb Pilot Project, is described. The project was created as a testbed for evaluating and prototyping key technologies for rapid acquisition and distribution of data products for decision support systems to monitor floods and enable flood risk assessment. The system provides access to real-time products on rainfall estimates and flood potential forecast derived from the Tropical Rainfall Measuring Mission (TRMM) mission with lag time of 6 h, alerts from the Global Disaster Alert and Coordination System (GDACS) with lag time of 4 h, and the Coupled Routing and Excess STorage (CREST) model to generate alerts. These are alerts are used to trigger satellite observations. With deployed SPS service for NASA's EO-1 satellite it is possible to automatically task sensor with re-image capability of less 8 h. Therefore, with enabled computational and storage services provided by Grid and cloud infrastructure it was possible to generate flood maps within 24-48 h after trigger was alerted. To enable interoperability between system components and services OGC-compliant standards are utilized. [1] Hluchy L., Kussul N., Shelestov A., Skakun S., Kravchenko O., Gripich Y., Kopp P., Lupian E., "The Data Fusion Grid Infrastructure: Project Objectives and Achievements," Computing and Informatics, 2010, vol. 29, no. 2, pp. 319-334.

Advancements in Open Geospatial Standards for Photogrammetry and Remote Sensing from Ogc

NASA Astrophysics Data System (ADS)

Percivall, George; Simonis, Ingo

2016-06-01

The necessity of open standards for effective sharing and use of remote sensing continues to receive increasing emphasis in policies of agencies and projects around the world. Coordination on the development of open standards for geospatial information is a vital step to insure that the technical standards are ready to support the policy objectives. The mission of the Open Geospatial Consortium (OGC) is to advance development and use of international standards and supporting services that promote geospatial interoperability. To accomplish this mission, OGC serves as the global forum for the collaboration of geospatial data / solution providers and users. Photogrammetry and remote sensing are sources of the largest and most complex geospatial information. Some of the most mature OGC standards for remote sensing include the Sensor Web Enablement (SWE) standards, the Web Coverage Service (WCS) suite of standards, encodings such as NetCDF, GMLJP2 and GeoPackage, and the soon to be approved Discrete Global Grid Systems (DGGS) standard. In collaboration with ISPRS, OGC working with government, research and industrial organizations continue to advance the state of geospatial standards for full use of photogrammetry and remote sensing.

Low-energy, low-budget sensor web enablement of an amateur weather station

NASA Astrophysics Data System (ADS)

Schmidt, G.; Herrnkind, S.; Klump, J.

2008-12-01

Sensor Web Enablement (OGC SWE) has developed in into a powerful concept with many potential applications in environmental monitoring and in other fields. This has spurred development of software applications for Sensor Observation Services (SOS), while the development of client applications still lags behind. Furthermore, the deployment of sensors in the field often places tight constraints on energy and bandwidth available for data capture and transmission. As a "proof of concept" we equipped an amateur weather station with low-budget, standard components to read the data from its base station and feed it into a sensor observation service using its standard web- service interface. We chose the weather station as an example because of its simple measured phenomena and its low data volume. As sensor observation service we chose the open source software package offered by the 52North consortium. Power consumption can be problematic when deploying a sensor platform in the field. Instead of a common PC we used a Network Storage Link Unit (NSLU2) with a Linux operating system, a configuration also known as "Debian SLUG". The power consumption of a "SLUG" is of the order of 2 to 5 Watt, compared to 40W in a small PC. The "SLUG" provides one ethernet and two USB ports, one used by its external USB hard-drive. This modular setup is open to modifications, for example the addition of a GSM modem for data transmission over a cellular telephone network. The simple setup, low price, low power consumption, and the low technological entry-level allow many potential uses of a "SLUG" in environmental sensor networks in research, education and citizen science. The use of a mature sensor observation service software allows an easy integration of monitoring networks with other web services.

Central Asia Water (CAWa) - A visualization platform for hydro-meteorological sensor data

NASA Astrophysics Data System (ADS)

Stender, Vivien; Schroeder, Matthias; Wächter, Joachim

2014-05-01

Water is an indispensable necessity of life for people in the whole world. In central Asia, water is the key factor for economic development, but is already a narrow resource in this region. In fact of climate change, the water problem handling will be a big challenge for the future. The regional research Network "Central Asia Water" (CAWa) aims at providing a scientific basis for transnational water resources management for the five Central Asia States Kyrgyzstan, Uzbekistan, Tajikistan, Turkmenistan and Kazakhstan. CAWa is part of the Central Asia Water Initiative (also known as the Berlin Process) which was launched by the Federal Foreign Office on 1 April 2008 at the "Water Unites" conference in Berlin. To produce future scenarios and strategies for sustainable water management, data on water reserves and the use of water in Central Asia must therefore be collected consistently across the region. Hydro-meteorological stations equipped with sophisticated sensors are installed in Central Asia and send their data via real-time satellite communication to the operation centre of the monitoring network and to the participating National Hydro-meteorological Services.[1] The challenge for CAWa is to integrate the whole aspects of data management, data workflows, data modeling and visualizations in a proper design of a monitoring infrastructure. The use of standardized interfaces to support data transfer and interoperability is essential in CAWa. An uniform treatment of sensor data can be realized by the OGC Sensor Web Enablement (SWE) , which makes a number of standards and interface definitions available: Observation & Measurement (O&M) model for the description of observations and measurements, Sensor Model Language (SensorML) for the description of sensor systems, Sensor Observation Service (SOS) for obtaining sensor observations, Sensor Planning Service (SPS) for tasking sensors, Web Notification Service (WNS) for asynchronous dialogues and Sensor Alert Service (SAS) for sending alerts. An OpenSource web-platform bundles the data, provided by the SWE web services of the hydro-meteorological stations, and provides tools for data visualization and data access. The visualization tool was implemented by using OpenSource tools like GeoExt/ExtJS and OpenLayers. Using the application the user can query the relevant sensor data, select parameter and time period, visualize and finally download the data. [1] http://www.cawa-project.net

An Interoperable Architecture for Air Pollution Early Warning System Based on Sensor Web

NASA Astrophysics Data System (ADS)

Samadzadegan, F.; Zahmatkesh, H.; Saber, M.; Ghazi khanlou, H. J.

2013-09-01

Environmental monitoring systems deal with time-sensitive issues which require quick responses in emergency situations. Handling the sensor observations in near real-time and obtaining valuable information is challenging issues in these systems from a technical and scientific point of view. The ever-increasing population growth in urban areas has caused certain problems in developing countries, which has direct or indirect impact on human life. One of applicable solution for controlling and managing air quality by considering real time and update air quality information gathered by spatially distributed sensors in mega cities, using sensor web technology for developing monitoring and early warning systems. Urban air quality monitoring systems using functionalities of geospatial information system as a platform for analysing, processing, and visualization of data in combination with Sensor Web for supporting decision support systems in disaster management and emergency situations. This system uses Sensor Web Enablement (SWE) framework of the Open Geospatial Consortium (OGC), which offers a standard framework that allows the integration of sensors and sensor data into spatial data infrastructures. SWE framework introduces standards for services to access sensor data and discover events from sensor data streams as well as definition set of standards for the description of sensors and the encoding of measurements. The presented system provides capabilities to collect, transfer, share, process air quality sensor data and disseminate air quality status in real-time. It is possible to overcome interoperability challenges by using standard framework. In a routine scenario, air quality data measured by in-situ sensors are communicated to central station where data is analysed and processed. The extracted air quality status is processed for discovering emergency situations, and if necessary air quality reports are sent to the authorities. This research proposed an architecture to represent how integrate air quality sensor data stream into geospatial data infrastructure to present an interoperable air quality monitoring system for supporting disaster management systems by real time information. Developed system tested on Tehran air pollution sensors for calculating Air Quality Index (AQI) for CO pollutant and subsequently notifying registered users in emergency cases by sending warning E-mails. Air quality monitoring portal used to retrieving and visualize sensor observation through interoperable framework. This system provides capabilities to retrieve SOS observation using WPS in a cascaded service chaining pattern for monitoring trend of timely sensor observation.

Is Diagnostic Performance of Quantitative 2D-Shear Wave Elastography Optimal for Clinical Classification of Benign and Malignant Thyroid Nodules?: A Systematic Review and Meta-analysis.

PubMed

Nattabi, Haliimah A; Sharif, Norhafidzah M; Yahya, Noorazrul; Ahmad, Rozilawati; Mohamad, Mazlyfarina; Zaki, Faizah M; Yusoff, Ahmad N

2017-10-17

This study is a dedicated 2D-shear wave elastography (2D-SWE) review aimed at systematically eliciting up-to-date evidence of its clinical value in differential diagnosis of benign and malignant thyroid nodules. PubMed, Web of Science, and Scopus databases were searched for studies assessing the diagnostic value of 2D-SWE for thyroid malignancy risk stratification published until December 2016. The retrieved titles and abstracts were screened and evaluated according to the predefined inclusion and exclusion criteria. Methodological quality of the studies was assessed using the Quality Assessment of Studies of Diagnostic Accuracy included in Systematic Review 2 (QUADAS-2) tool. Extracted 2D-SWE diagnostic performance data were meta-analyzed to assess the summary sensitivity, specificity, and area under the receiver operating characteristic curve. After stepwise review, 14 studies in which 2D-SWE was used to evaluate 2851 thyroid nodules (1092 malignant, 1759 benign) from 2139 patients were selected for the current study. Study quality on QUADAS-2 assessment was moderate to high. The summary sensitivity, specificity and area under the receiver operating characteristic curve of 2D-SWE for differential diagnosis of benign and malignant thyroid nodules were 0.66 (95% confidence interval [CI]: 0.64-0.69), 0.78 (CI: 0.76-0.80), and 0.851 (Q* = 0.85), respectively. The pooled diagnostic odds ratio, negative likelihood ratio, and positive likelihood ratio were 12.73 (CI: 8.80-18.43), 0.31 (CI: 0.22-0.44), and 3.87 (CI: 2.83-5.29), respectively. Diagnostic performance of quantitative 2D-SWE for malignancy risk stratification of thyroid nodules is suboptimal with mediocre sensitivity and specificity, contrary to earlier reports of excellence. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Machine Learning on Images: Combining Passive Microwave and Optical Data to Estimate Snow Water Equivalent

NASA Astrophysics Data System (ADS)

Dozier, J.; Tolle, K.; Bair, N.

2014-12-01

We have a problem that may be a specific example of a generic one. The task is to estimate spatiotemporally distributed estimates of snow water equivalent (SWE) in snow-dominated mountain environments, including those that lack on-the-ground measurements. Several independent methods exist, but all are problematic. The remotely sensed date of disappearance of snow from each pixel can be combined with a calculation of melt to reconstruct the accumulated SWE for each day back to the last significant snowfall. Comparison with streamflow measurements in mountain ranges where such data are available shows this method to be accurate, but the big disadvantage is that SWE can only be calculated retroactively after snow disappears, and even then only for areas with little accumulation during the melt season. Passive microwave sensors offer real-time global SWE estimates but suffer from several issues, notably signal loss in wet snow or in forests, saturation in deep snow, subpixel variability in the mountains owing to the large (~25 km) pixel size, and SWE overestimation in the presence of large grains such as depth and surface hoar. Throughout the winter and spring, snow-covered area can be measured at sub-km spatial resolution with optical sensors, with accuracy and timeliness improved by interpolating and smoothing across multiple days. So the question is, how can we establish the relationship between Reconstruction—available only after the snow goes away—and passive microwave and optical data to accurately estimate SWE during the snow season, when the information can help forecast spring runoff? Linear regression provides one answer, but can modern machine learning techniques (used to persuade people to click on web advertisements) adapt to improve forecasts of floods and droughts in areas where more than one billion people depend on snowmelt for their water resources?

Distributive, Non-destructive Real-time System and Method for Snowpack Monitoring

NASA Technical Reports Server (NTRS)

Frolik, Jeff (Inventor); Skalka, Christian (Inventor)

2013-01-01

A ground-based system that provides quasi real-time measurement and collection of snow-water equivalent (SWE) data in remote settings is provided. The disclosed invention is significantly less expensive and easier to deploy than current methods and less susceptible to terrain and snow bridging effects. Embodiments of the invention include remote data recovery solutions. Compared to current infrastructure using existing SWE technology, the disclosed invention allows more SWE sites to be installed for similar cost and effort, in a greater variety of terrain; thus, enabling data collection at improved spatial resolutions. The invention integrates a novel computational architecture with new sensor technologies. The invention's computational architecture is based on wireless sensor networks, comprised of programmable, low-cost, low-powered nodes capable of sophisticated sensor control and remote data communication. The invention also includes measuring attenuation of electromagnetic radiation, an approach that is immune to snow bridging and significantly reduces sensor footprints.

ISTIMES Integrated System for Transport Infrastructures Surveillance and Monitoring by Electromagnetic Sensing

NASA Astrophysics Data System (ADS)

Argenti, M.; Giannini, V.; Averty, R.; Bigagli, L.; Dumoulin, J.

2012-04-01

The EC FP7 ISTIMES project has the goal of realizing an ICT-based system exploiting distributed and local sensors for non destructive electromagnetic monitoring in order to make critical transport infrastructures more reliable and safe. Higher situation awareness thanks to real time and detailed information and images of the controlled infrastructure status allows improving decision capabilities for emergency management stakeholders. Web-enabled sensors and a service-oriented approach are used as core of the architecture providing a sys-tem that adopts open standards (e.g. OGC SWE, OGC CSW etc.) and makes efforts to achieve full interoperability with other GMES and European Spatial Data Infrastructure initiatives as well as compliance with INSPIRE. The system exploits an open easily scalable network architecture to accommodate a wide range of sensors integrated with a set of tools for handling, analyzing and processing large data volumes from different organizations with different data models. Situation Awareness tools are also integrated in the system. Definition of sensor observations and services follows a metadata model based on the ISO 19115 Core set of metadata elements and the O&M model of OGC SWE. The ISTIMES infrastructure is based on an e-Infrastructure for geospatial data sharing, with a Data Cata-log that implements the discovery services for sensor data retrieval, acting as a broker through static connections based on standard SOS and WNS interfaces; a Decision Support component which helps decision makers providing support for data fusion and inference and generation of situation indexes; a Presentation component which implements system-users interaction services for information publication and rendering, by means of a WEB Portal using SOA design principles; A security framework using Shibboleth open source middleware based on the Security Assertion Markup Language supporting Single Sign On (SSO). ACKNOWLEDGEMENT - The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under Grant Agreement n° 225663

Seasonal Snow Cold Content Dynamics in the Alpine and Sub-Alpine, Niwot Ridge, Colorado, USA

NASA Astrophysics Data System (ADS)

Jennings, K. S.; Molotch, N. P.

2015-12-01

Cold content represents the energy required to warm a sub-freezing snowpack to an isothermal 0°C. Across daily and seasonal time scales it is a dynamic interplay between the forces of snowpack accumulation/cooling and warming. Cold content determines snowmelt timing and is an important component of the annual energy budget of mountain sites with seasonal snowpacks. However, little is understood about seasonal snowpack cold content dynamics as calculating cold content requires depth-weighted snowpack temperature and snow water equivalent (SWE) measurements, which are scarce. A spatially distributed network of snow pits has been sampled since 1993 at the Niwot Ridge Long Term Ecological Research site on the eastern slope of the Continental Divide in Colorado's Front Range mountains. This study uses data from 3 pit sites that have at least 8 years of observations and represent alpine and sub-alpine environments. For these pits, cold content is strongly related to SWE during the cold content accumulation phase, here defined as December, January, and February. Average peak cold content ranges between -2.5 MJ m-2 and -9.2 MJ m-2 for the three sites and is strongly related to peak SWE. On average, cold content reaches its maximum on February 26, which is 61 days before the average date of peak SWE (i.e., the snowpack's cold content is satisfied over an average of 61 days). At the alpine site, later peak cold content and SWE was observed relative to the lower elevation sub-alpine sites. Interestingly, the alpine site had a smaller gap between peak cold content and SWE (55 days versus 67 days for the alpine and sub-alpine sites, respectively). The gap between peak cold content and peak SWE is primarily a function of the increase in SWE between the two dates. Hence, persistent snowfall after the date of peak cold content can delay the onset of snowmelt even if peak cold content was relatively low. Improving our understanding of seasonal cold content dynamics in mountain environments will enable us to better model the future effects of climate change on snowmelt timing and associated hydrologic response.

Sensor web enablement in a network of low-energy, low-budget amateur weather stations

NASA Astrophysics Data System (ADS)

Herrnkind, S.; Klump, J.; Schmidt, G.

2009-04-01

Sensor Web Enablement (OGC SWE) has developed in into a powerful concept with many potential applications in environmental monitoring and in other fields. This has spurred development of software applications for Sensor Observation Services (SOS), while the development of client applications still lags behind. Furthermore, the deployment of sensors in the field often places tight constraints on energy and bandwidth available for data capture and transmission. As a „proof of concept" we equipped amateur weather stations with low-budget, standard components to read the data from its base station and feed the weather observation data into the sensor observation service using its standard web-service interface. We chose amateur weather station as an example because of the simplicity of measured phenomena and low data volume. As sensor observation service we chose the open source software package offered by the 52°North consortium. Furthermore, we investigated registry services for sensors and measured phenomena. When deploying a sensor platform in the field, power consumption can be an issue. Instead of common PCs we used Network Storage Link Units (NSLU2) with a Linux operating system, also known as "Debian SLUG". The power consumption of a "SLUG" is of the order of 1W, compared to 40W in a small PC. The "SLUG" provides one ethernet and two USB ports, one used by its external USB hard-drive. This modular set-up is open to modifications, for example the addition of a GSM modem for data transmission over a cellular telephone network. The simple set-up, low price, low power consumption, and the low technological entry-level allow many potential uses of a "SLUG" in environmental sensor networks in research, education and citizen science. The use of a mature sensor observation service software allows an easy integration of monitoring networks with other web services.

Determinants of Swe1p Degradation in Saccharomyces cerevisiae

PubMed Central

McMillan, John N.; Theesfeld, Chandra L.; Harrison, Jacob C.; Bardes, Elaine S. G.; Lew, Daniel J.

2002-01-01

Swe1p, the sole Wee1-family kinase in Saccharomyces cerevisiae, is synthesized during late G1 and is then degraded as cells proceed through the cell cycle. However, Swe1p degradation is halted by the morphogenesis checkpoint, which responds to insults that perturb bud formation. The Swe1p stabilization promotes cell cycle arrest through Swe1p-mediated inhibitory phosphorylation of Cdc28p until the cells can recover from the perturbation and resume bud formation. Swe1p degradation involves the relocalization of Swe1p from the nucleus to the mother-bud neck, and neck targeting requires the Swe1p-interacting protein Hsl7p. In addition, Swe1p degradation is stimulated by its substrate, cyclin/Cdc28p, and Swe1p is thought to be a target of the ubiquitin ligase SCFMet30 acting with the ubiquitin-conjugating enzyme Cdc34p. The basis for regulation of Swe1p degradation by the morphogenesis checkpoint remains unclear, and in order to elucidate that regulation we have dissected the Swe1p degradation pathway in more detail, yielding several novel findings. First, we show here that Met30p (and by implication SCFMet30) is not, in fact, required for Swe1p degradation. Second, cyclin/Cdc28p does not influence Swe1p neck targeting, but can directly phosphorylate Swe1p, suggesting that it acts downstream of neck targeting in the Swe1p degradation pathway. Third, a screen for functional but nondegradable mutants of SWE1 identified two small regions of Swe1p that are key to its degradation. One of these regions mediates interaction of Swe1p with Hsl7p, showing that the Swe1p-Hsl7p interaction is critical for Swe1p neck targeting and degradation. The other region did not appear to affect interactions with known Swe1p regulators, suggesting that other as-yet-unknown regulators exist. PMID:12388757

SWANN: The Snow Water Artificial Neural Network Modelling System

NASA Astrophysics Data System (ADS)

Broxton, P. D.; van Leeuwen, W.; Biederman, J. A.

2017-12-01

Snowmelt from mountain forests is important for water supply and ecosystem health. Along Arizona's Mogollon Rim, snowmelt contributes to rivers and streams that provide a significant water supply for hydro-electric power generation, agriculture, and human consumption in central Arizona. In this project, we are building a snow monitoring system for the Salt River Project (SRP), which supplies water and power to millions of customers in the Phoenix metropolitan area. We are using process-based hydrological models and artificial neural networks (ANNs) to generate information about both snow water equivalent (SWE) and snow cover. The snow-cover data is generated with ANNs that are applied to Landsat and MODIS satellite reflectance data. The SWE data is generated using a combination of gridded SWE estimates generated by process-based snow models and ANNs that account for variations in topography, forest cover, and solar radiation. The models are trained and evaluated with snow data from SNOTEL stations as well as from aerial LiDAR and field data that we collected this past winter in northern Arizona, as well as with similar data from other sites in the Southwest US. These snow data are produced in near-real time, and we have built a prototype decision support tool to deliver them to SRP. This tool is designed to provide daily-to annual operational monitoring of spatial and temporal changes in SWE and snow cover conditions over the entire Salt River Watershed (covering 17,000 km2), and features advanced web mapping capabilities and watershed analytics displayed as graphical data.

Sensor Alerting Capability

NASA Astrophysics Data System (ADS)

Henriksson, Jakob; Bermudez, Luis; Satapathy, Goutam

2013-04-01

There is a large amount of sensor data generated today by various sensors, from in-situ buoys to mobile underwater gliders. Providing sensor data to the users through standardized services, language and data model is the promise of OGC's Sensor Web Enablement (SWE) initiative. As the amount of data grows it is becoming difficult for data providers, planners and managers to ensure reliability of data and services and to monitor critical data changes. Intelligent Automation Inc. (IAI) is developing a net-centric alerting capability to address these issues. The capability is built on Sensor Observation Services (SOSs), which is used to collect and monitor sensor data. The alerts can be configured at the service level and at the sensor data level. For example it can alert for irregular data delivery events or a geo-temporal statistic of sensor data crossing a preset threshold. The capability provides multiple delivery mechanisms and protocols, including traditional techniques such as email and RSS. With this capability decision makers can monitor their assets and data streams, correct failures or be alerted about a coming phenomena.

Shear-wave elastography: a new potential method to diagnose ulnar neuropathy at the elbow.

PubMed

Paluch, Łukasz; Noszczyk, Bartłomiej; Nitek, Żaneta; Walecki, Jerzy; Osiak, Katarzyna; Pietruski, Piotr

2018-06-01

The primary aim of this study was to verify if shear-wave elastography (SWE) can be used to diagnose ulnar neuropathy at the elbow (UNE). The secondary objective was to compare the cross-sectional areas (CSA) of the ulnar nerve in the cubital tunnel and to determine a cut-off value for this parameter accurately identifying persons with UNE. The study included 34 patients with UNE (mean age, 59.35 years) and 38 healthy controls (mean age, 57.42 years). Each participant was subjected to SWE of the ulnar nerve at three levels: in the cubital tunnel (CT) and at the distal arm (DA) and mid-arm (MA). The CSA of the ulnar nerve in the cubital tunnel was estimated by means of ultrasonographic imaging. Patients with UNE presented with significantly greater ulnar nerve stiffness in the cubital tunnel than the controls (mean, 96.38 kPa vs. 33.08 kPa, p < 0.001). Ulnar nerve stiffness of 61 kPa, CT to DA stiffness ratio equal 1.68, and CT to MA stiffness ratio of 1.75 provided 100% specificity, sensitivity, positive and negative predictive value in the detection of UNE. Mean CSA of the ulnar nerve in the cubital tunnel turned out to be significantly larger in patients with UNE than in healthy controls (p < 0.001). A weak positive correlation was found in the UNE group between the ulnar nerve CSA and stiffness (R = 0.31, p = 0.008). SWE seems to be a promising, reliable and simple quantitative adjunct test to support the diagnosis of UNE. • SWE enables reliable detection of cubital tunnel syndrome • Significant increase of entrapped ulnar nerve stiffness is observed in UNE • SWE is a perspective screening tool for early detection of compressive neuropathies.

We have "born digital" - now what about "born semantic"?

NASA Astrophysics Data System (ADS)

Leadbetter, Adam; Fredericks, Janet

2014-05-01

The phrase "born-digital" refers to those materials which originate in a digital form. In Earth and Space Sciences, this is now very much the norm for data: analogue to digital converters sit on instrument boards and produce a digital record of the observed environment. While much effort has been put in to creating and curating these digital data, there has been little work on using semantic mark up of data from the point of collection - what we term 'born semantic'. In this presentation we report on two efforts to expand this area: Qartod-to-OGC (Q2O) and SenseOCEAN. These projects have taken a common approach to 'born semantic': create or reuse appropriate controlled vocabularies, published to World Wide Web Commission (W3C) standards use standards from the Open Geospatial Consortium's Sensor Web Enablement (SWE) initiative to describe instrument setup, deployment and/or outputs using terms from those controlled vocabularies embed URLs from the controlled vocabularies within the SWE documents in a "Linked Data" conformant approach Q2O developed best practices examples of SensorML descriptions of Original Equipment Manufacturers' metadata (model characteristics, capabilities, manufacturer contact, etc ...) set-up and deployment SensorML files; and data centre process-lineage using registered vocabularies to describe terms (including input, output, processes, parameters, quality control flags) One Q2O use case, the Martha's Vineyard Coastal Observatory ADCP Waves instance, uses SensorML and registered vocabularies to fully describe the process of computing wave parameters from sensed properties, including quality control tests and associated results. The European Commission Framework Programme 7 project SenseOCEAN draws together world leading marine sensor developers to create a highly integrated multifunction and cost-effective in situ marine biogeochemical sensor system. This project will provide a quantum leap in the ability to measure crucial biogeochemical parameters. Innovations will be combined with state of the art sensor technology to produce a modular sensor system that can be deployed on many platforms. The sensor descriptions are being profiled in SensorML and the controlled vocabularies are being repurposed from those used within the European Commission SeaDataNet project and published on the community standard NERC Vocabulary Server.

Two-dimensional shear wave elastography of breast lesions: Comparison of two different systems.

PubMed

Ren, Wei-Wei; Li, Xiao-Long; He, Ya-Ping; Li, Dan-Dan; Wang, Dan; Zhao, Chong-Ke; Bo, Xiao-Wan; Liu, Bo-Ji; Yue, Wen-Wen; Xu, Hui-Xiong

2017-01-01

To evaluate the diagnostic performance of two different shear wave elastography (SWE) techniques in distinguishing malignant breast lesions from benign ones. From March 2016 to May 2016, a total of 153 breast lesions (mean diameter, 16.8 mm±10.5; range 4.1-90.0 mm) in 153 patients (mean age, 46.4 years±15.1; age range 20-86 years) were separately performed by two different SWE techniques (i.e. T-SWE, Aplio500, Toshiba Medical System, Tochigi, Japan; and S-SWE, the Aixplorer US system, SuperSonic Imagine, Provence, France). The maximum (Emax), mean (Emean) and standard deviation (ESD) of elasticity modulus values in T-SWE and S-SWE were analyzed. All the lesions were confirmed by ultrasound (US)-guided core needle biopsy (n = 26), surgery (n = 122), or both (n = 5), with pathological results as the gold standard. The areas under the receiver operating characteristic curves (AUROCs) were calculated. Sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV) were calculated to assess the diagnostic performance between T-SWE and S-SWE. Operator consistency was also evaluated. Among the 153 lesions, 41 (26.8%) were malignant and 112 (73.2%) were benign. Emax (T-SWE: 40.10±37.14 kPa vs. 118.78±34.41 kPa; S-SWE: 41.22±22.54 kPa vs. 134.77±60.51 kPa), Emean (T-SWE: 19.75±16.31 kPa vs. 52.93±25.75 kPa; S-SWE: 20.95±10.98 kPa vs. 55.95±22.42 kPa) and ESD (T-SWE: 9.00±8.55 kPa vs. 38.44±12.30 kPa; S-SWE: 8.17±6.14 kPa vs. 29.34±13.88 kPa) showed statistical differences in distinguishing malignant lesions from benign ones both in T-SWE and S-SWE (all p < 0.05). In T-SWE, the diagnostic performance of ESD was the highest (AUROC = 0.958), followed by Emax (AUROC = 0.909; p = 0.001 in comparison with ESD) and Emean (AUROC = 0.892; p < 0.001 in comparison with ESD), while in S-SWE, the diagnostic performance of Emax was the highest (AUROC = 0.967), followed by ESD (AUROC = 0.962, p > 0.05 in comparison with Emax) and Emean (AUROC = 0.930, p = 0.034 in comparison with Emax). AUROC-max (T-SWE: 0.909 vs. 0.967), AUROC-mean (T-SWE: 0.892 vs. 0.930) and AUROC-SD (T-SWE: 0.958 vs. 0.962) showed no significant difference between T-SWE and S-SWE (all p > 0.05). The intra-class correlation coefficients (ICC) of the intra-operator consistency and inter-operator consistency respectively were 0.961 and 0.898 in T-SWE, while 0.954 and 0.897 in S-SWE. T-SWE and S-SWE are equivalent for distinguishing the breast lesions. In T-SWE, ESD had the best diagnostic performance, while in S-SWE, Emax had the best diagnostic performance.

Shear-wave elastography of the liver and spleen identifies clinically significant portal hypertension: A prospective multicentre study.

PubMed

Jansen, Christian; Bogs, Christopher; Verlinden, Wim; Thiele, Maja; Möller, Philipp; Görtzen, Jan; Lehmann, Jennifer; Vanwolleghem, Thomas; Vonghia, Luisa; Praktiknjo, Michael; Chang, Johannes; Krag, Aleksander; Strassburg, Christian P; Francque, Sven; Trebicka, Jonel

2017-03-01

Clinically significant portal hypertension (CSPH) is associated with severe complications and decompensation of cirrhosis. Liver stiffness measured either by transient elastography (TE) or Shear-wave elastography (SWE) and spleen stiffness by TE might be helpful in the diagnosis of CSPH. We recently showed the algorithm to rule-out CSPH using sequential liver- (L-SWE) and spleen-Shear-wave elastography (S-SWE). This study investigated the diagnostic value of S-SWE for diagnosis of CSPH. One hundred and fifty-eight cirrhotic patients with pressure gradient measurements were included into this prospective multicentre study. L-SWE was measured in 155 patients, S-SWE in 112 patients, and both in 109 patients. Liver-shear-wave elastography and S-SWE correlated with clinical events and decompensation. SWE of liver and spleen revealed strong correlations with the pressure gradient and to differentiate between patients with and without CSPH. The best cut-off values were 24.6 kPa:L-SWE and 26.3 kPa:S-SWE. L-SWE ≤16.0 kPa and S-SWE ≤21.7 kPa were able to rule-out CSPH. Cut-off values of L-SWE >29.5 kPa and S-SWE >35.6 kPa were able to rule-in CSPH (specificity >92%). Patients with a L-SWE >38.0 kPa had likely CSPH. In patients with L-SWE ≤38.0 kPa, a S-SWE >27.9 kPa ruled in CSPH. This algorithm has a sensitivity of 89.2% and a specificity of 91.4% to rule-in CSPH. Patients not fulfilling these criteria may undergo HVPG measurement. Liver and spleen SWE correlate with portal pressure and can both be used as a non-invasive method to investigate CSPH. Even though external validation is still missing, these algorithms to rule-out and rule-in CSPH using sequential SWE of liver and spleen might change the clinical practice. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Performance Characteristics of the Electronic Snow Water Equivalent (SWE) Sensor in Arctic, Marine, and Humid Continental Climates

NASA Astrophysics Data System (ADS)

Johnson, J.; Gelvin, A. B.; Duvoy, P.; Schaefer, G. L.; Poole, G.; Horton, G. D.

2011-12-01

The USA ERDC CRREL and the USDA NRCS developed a 3-m square electronic SWE sensor (e-SWE sensor) consisting of nine perforated panels (a center panel to measure SWE and eight outer panels to buffer edge stress concentrations). Seven e-SWE sensors were installed in five different climate zones including north central and north coastal Alaska, Oregon, Newfoundland, and New York State. With the exception of New York State, the e-SWE sensors accurately measured SWE. The e-SWE sensor at Hogg Pass, OR, accurately measured SWE during five years of observations even when edge stress concentrations occurred. In windy conditions of northern Alaska, the sensor measured losses and gains in SWE with more reliability and higher accuracy than other standard methods. The sensor also detected snowdrift migration (comparing video and sensor measurements). In the thin, icy snow of New York the electronic SWE sensors over-measured SWE during midwinter. Over-measurement errors were caused by edge stress concentrations associated with strong icy layers, a shallow snow cover and possibly using a backfill material with different thermal properties and a large freeboard compared to the surrounding soil . Measurement accuracy improved in spring due to increased snow creep, associated with warming snow temperatures, which reduced edge stress concentrations.

Three-dimensional shear wave elastography for differentiation of breast lesions: An initial study with quantitative analysis using three orthogonal planes.

PubMed

Wang, Qiao

2018-05-25

To prospectively evaluate the diagnostic performance of three-dimensional (3D) shear wave elastography (SWE) for breast lesions with quantitative stiffness information from transverse, sagittal and coronal planes. Conventional ultrasound (US), two-dimensional (2D)-SWE and 3D-SWE were performed for 122 consecutive patients with 122 breast lesions before biopsy or surgical excision. Maximum elasticity values of Young's modulus (Emax) were recorded on 2D-SWE and three planes of 3D-SWE. Area under the receiver operating characteristic curve (AUC), sensitivity and specificity of US, 2D-SWE and 3D-SWE were evaluated. Two combined sets (i.e., BI-RADS and 2D-SWE; BI-RADS and 3D-SWE) were compared in AUC. Observer consistency was also evaluated. On 3D-SWE, the AUC and sensitivity of sagittal plane were significantly higher than those of transverse and coronal planes (both P < 0.05). Compared with BI-RADS alone, both combined sets had significantly (P < 0.05) higher AUCs and specificities, whereas, the two combined sets showed no significant difference in AUC (P > 0.05). However, the combined set of BI-RADS and sagittal plane of 3D-SWE had significantly higher sensitivity than the combined set of BI-RADS and 2D-SWE. The sagittal plane shows the best diagnostic performance among 3D-SWE. The combination of BI-RADS and 3D-SWE is a useful tool for predicting breast malignant lesions in comparison with BI-RADS alone.

Kinota: An Open-Source NoSQL implementation of OGC SensorThings for large-scale high-resolution real-time environmental monitoring

NASA Astrophysics Data System (ADS)

Miles, B.; Chepudira, K.; LaBar, W.

2017-12-01

The Open Geospatial Consortium (OGC) SensorThings API (STA) specification, ratified in 2016, is a next-generation open standard for enabling real-time communication of sensor data. Building on over a decade of OGC Sensor Web Enablement (SWE) Standards, STA offers a rich data model that can represent a range of sensor and phenomena types (e.g. fixed sensors sensing fixed phenomena, fixed sensors sensing moving phenomena, mobile sensors sensing fixed phenomena, and mobile sensors sensing moving phenomena) and is data agnostic. Additionally, and in contrast to previous SWE standards, STA is developer-friendly, as is evident from its convenient JSON serialization, and expressive OData-based query language (with support for geospatial queries); with its Message Queue Telemetry Transport (MQTT), STA is also well-suited to efficient real-time data publishing and discovery. All these attributes make STA potentially useful for use in environmental monitoring sensor networks. Here we present Kinota(TM), an Open-Source NoSQL implementation of OGC SensorThings for large-scale high-resolution real-time environmental monitoring. Kinota, which roughly stands for Knowledge from Internet of Things Analyses, relies on Cassandra its underlying data store, which is a horizontally scalable, fault-tolerant open-source database that is often used to store time-series data for Big Data applications (though integration with other NoSQL or rational databases is possible). With this foundation, Kinota can scale to store data from an arbitrary number of sensors collecting data every 500 milliseconds. Additionally, Kinota architecture is very modular allowing for customization by adopters who can choose to replace parts of the existing implementation when desirable. The architecture is also highly portable providing the flexibility to choose between cloud providers like azure, amazon, google etc. The scalable, flexible and cloud friendly architecture of Kinota makes it ideal for use in next-generation large-scale and high-resolution real-time environmental monitoring networks used in domains such as hydrology, geomorphology, and geophysics, as well as management applications such as flood early warning, and regulatory enforcement.

Point shear wave ultrasound elastography with Esaote compared to real-time 2D shear wave elastography with supersonic imagine for the quantification of liver stiffness.

PubMed

Mulazzani, L; Salvatore, V; Ravaioli, F; Allegretti, G; Matassoni, F; Granata, R; Ferrarini, A; Stefanescu, H; Piscaglia, Fabio

2017-09-01

Different shear wave elastography (SWE) machines able to quantify liver stiffness (LS) have been recently introduced by various companies. The aim of this study was to investigate the agreement between point SWE with Esaote MyLab Twice (pSWE.ESA) and 2D SWE with Aixplorer SuperSonic (2D SWE.SSI). Moreover, we assessed the correlation of these machines with Fibroscan in a subgroup of patients. A total of 81 liver disease patients and 27 subjects without liver disease accessing the ultrasound lab were considered. Exclusion criteria were liver nodules, BMI >35, and severe comorbidities. LS was sampled from the same intercostal space with both pSWE.ESA and 2D SWE.SSI and values were tested with Lin's analysis and Bland-Altman analysis (B&A). Agreement between each SWE machine and Fibroscan was assessed in 26 liver disease patients with Spearman correlation. Precision and accuracy between pSWE.ESA and 2D SWE.SSI were, respectively, 0.839 and 0.999. B&A showed a mean of only -0.2 kPa, with no systematic deviation between the techniques and limits of agreement at -11.6 and 11.3 kPa. Spearman's rho correlation versus Fibroscan was 0.849 for pSWE.ESA and 0.878 for 2D SWE.SSI. The relationship became less strict in the higher range of LS (≥15.2 kPa), corresponding to cirrhosis. The overall degree of concordance of pSWE.ESA and 2D SWE.SSI in measuring LS resulted remarkable, also when compared with Fibroscan. The less strict correlation for patients with LS in the higher range would not affect the staging of disease as such patients are anyhow classified as cirrhotic.

Diagnostic performance and color overlay pattern in shear wave elastography (SWE) for palpable breast mass.

PubMed

Park, Jiyoon; Woo, Ok Hee; Shin, Hye Seon; Cho, Kyu Ran; Seo, Bo Kyoung; Kang, Eun Young

2015-10-01

The purpose of this study is to evaluate the diagnostic performance of SWE in palpable breast mass and to compare with color overlay pattern in SWE with conventional US and quantitative SWE for assessing palpable breast mass. SWE and conventional breast US were performed in 133 women with 156 palpable breast lesions (81 benign, 75 malignant) between August 2013 to June 2014. Either pathology or periodic imaging surveillance more than 2 years was a reference standard. Existence of previous image was blinded to performing radiologists. US BI-RADS final assessment, qualitative and quantitative SWE measurements were evaluated. Diagnostic performances of grayscale US, SWE and US combined to SWE were calculated and compared. Correlation between pattern classification and quantitative SWE was evaluated. Both color overlay pattern and quantitative SWE improved the specificity of conventional US, from 81.48% to 96.30% (p=0.0005), without improvement in sensitivity. Color overlay pattern was significantly related to all quantitative SWE parameters and malignancy rate (p<0.0001.). The optimal cutoff of color overlay pattern was between 2 and 3. Emax with optimal cutoff at 45.1 kPa showed the highest Az value, sensitivity, specificity and accuracy among other quantitative SWE parameters (p<0.0001). Echogenic halo on grayscale US showed significant correlation with color overlay pattern and pathology (p<0.0001). In evaluation of palpable breast mass, conventional US combine to SWE improves specificity and reduces the number of biopsies that ultimately yield a benign result. Color overlay pattern classification is more quick and easy and may represent quantitative SWE measurements with similar diagnostic performances. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Qualitative pattern classification of shear wave elastography for breast masses: how it correlates to quantitative measurements.

PubMed

Yoon, Jung Hyun; Ko, Kyung Hee; Jung, Hae Kyoung; Lee, Jong Tae

2013-12-01

To determine the correlation of qualitative shear wave elastography (SWE) pattern classification to quantitative SWE measurements and whether it is representative of quantitative SWE values with similar performances. From October 2012 to January 2013, 267 breast masses of 236 women (mean age: 45.12 ± 10.54 years, range: 21-88 years) who had undergone ultrasonography (US), SWE, and subsequent biopsy were included. US BI-RADS final assessment and qualitative and quantitative SWE measurements were recorded. Correlation between pattern classification and mean elasticity, maximum elasticity, elasticity ratio and standard deviation were evaluated. Diagnostic performances of grayscale US, SWE parameters, and US combined to SWE values were calculated and compared. Of the 267 breast masses, 208 (77.9%) were benign and 59 (22.1%) were malignant. Pattern classifications significantly correlated with all quantitative SWE measurements, showing highest correlation with maximum elasticity, r = 0.721 (P<0.001). Sensitivity was significantly decreased in US combined to SWE measurements to grayscale US: 69.5-89.8% to 100.0%, while specificity was significantly improved: 62.5-81.7% to 13.9% (P<0.001). Area under the ROC curve (Az) did not show significant differences between grayscale US to US combined to SWE (P>0.05). Pattern classification shows high correlation to maximum stiffness and may be representative of quantitative SWE values. When combined to grayscale US, SWE improves specificity of US. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Evaluation and Application of Gridded Snow Water Equivalent Products for Improving Snowmelt Flood Predictions in the Red River Basin of the North

NASA Astrophysics Data System (ADS)

Schroeder, R.; Jacobs, J. M.; Vuyovich, C.; Cho, E.; Tuttle, S. E.

2017-12-01

Each spring the Red River basin (RRB) of the North, located between the states of Minnesota and North Dakota and southern Manitoba, is vulnerable to dangerous spring snowmelt floods. Flat terrain, low permeability soils and a lack of satisfactory ground observations of snow pack conditions make accurate predictions of the onset and magnitude of major spring flood events in the RRB very challenging. This study investigated the potential benefit of using gridded snow water equivalent (SWE) products from passive microwave satellite missions and model output simulations to improve snowmelt flood predictions in the RRB using NOAA's operational Community Hydrologic Prediction System (CHPS). Level-3 satellite SWE products from AMSR-E, AMSR2 and SSM/I, as well as SWE computed from Level-2 brightness temperatures (Tb) measurements, including model output simulations of SWE from SNODAS and GlobSnow-2 were chosen to support the snowmelt modeling exercises. SWE observations were aggregated spatially (i.e. to the NOAA North Central River Forecast Center forecast basins) and temporally (i.e. by obtaining daily screened and weekly unscreened maximum SWE composites) to assess the value of daily satellite SWE observations relative to weekly maximums. Data screening methods removed the impacts of snow melt and cloud contamination on SWE and consisted of diurnal SWE differences and a temperature-insensitive polarization difference ratio, respectively. We examined the ability of the satellite and model output simulations to capture peak SWE and investigated temporal accuracies of screened and unscreened satellite and model output SWE. The resulting SWE observations were employed to update the SNOW-17 snow accumulation and ablation model of CHPS to assess the benefit of using temporally and spatially consistent SWE observations for snow melt predictions in two test basins in the RRB.

Improving snow density estimation for mapping SWE with Lidar snow depth: assessment of uncertainty in modeled density and field sampling strategies in NASA SnowEx

NASA Astrophysics Data System (ADS)

Raleigh, M. S.; Smyth, E.; Small, E. E.

2017-12-01

The spatial distribution of snow water equivalent (SWE) is not sufficiently monitored with either remotely sensed or ground-based observations for water resources management. Recent applications of airborne Lidar have yielded basin-wide mapping of SWE when combined with a snow density model. However, in the absence of snow density observations, the uncertainty in these SWE maps is dominated by uncertainty in modeled snow density rather than in Lidar measurement of snow depth. Available observations tend to have a bias in physiographic regime (e.g., flat open areas) and are often insufficient in number to support testing of models across a range of conditions. Thus, there is a need for targeted sampling strategies and controlled model experiments to understand where and why different snow density models diverge. This will enable identification of robust model structures that represent dominant processes controlling snow densification, in support of basin-scale estimation of SWE with remotely-sensed snow depth datasets. The NASA SnowEx mission is a unique opportunity to evaluate sampling strategies of snow density and to quantify and reduce uncertainty in modeled snow density. In this presentation, we present initial field data analyses and modeling results over the Colorado SnowEx domain in the 2016-2017 winter campaign. We detail a framework for spatially mapping the uncertainty in snowpack density, as represented across multiple models. Leveraging the modular SUMMA model, we construct a series of physically-based models to assess systematically the importance of specific process representations to snow density estimates. We will show how models and snow pit observations characterize snow density variations with forest cover in the SnowEx domains. Finally, we will use the spatial maps of density uncertainty to evaluate the selected locations of snow pits, thereby assessing the adequacy of the sampling strategy for targeting uncertainty in modeled snow density.

The Snowcloud System: Architecture and Algorithms for Snow Hydrology Studies

NASA Astrophysics Data System (ADS)

Skalka, C.; Brown, I.; Frolik, J.

2013-12-01

Snowcloud is an embedded data collection system for snow hydrology field research campaigns conducted in harsh climates and remote areas. The system combines distributed wireless sensor network technology and computational techniques to provide data at lower cost and higher spatio-temporal resolution than ground-based systems using traditional methods. Snowcloud has seen multiple Winter deployments in settings ranging from high desert to arctic, resulting in over a dozen node-years of practical experience. The Snowcloud system architecture consists of multiple TinyOS mesh-networked sensor stations collecting environmental data above and, in some deployments, below the snowpack. Monitored data modalities include snow depth, ground and air temperature, PAR and leaf-area index (LAI), and soil moisture. To enable power cycling and control of multiple sensors a custom power and sensor conditioning board was developed. The electronics and structural systems for individual stations have been designed and tested (in the lab and in situ) for ease of assembly and robustness to harsh winter conditions. Battery systems and solar chargers enable seasonal operation even under low/no light arctic conditions. Station costs range between 500 and 1000 depending on the instrumentation suite. For remote field locations, a custom designed hand-held device and data retrieval protocol serves as the primary data collection method. We are also developing and testing a Gateway device that will report data in near-real-time (NRT) over a cellular connection. Data is made available to users via web interfaces that also provide basic data analysis and visualization tools. For applications to snow hydrology studies, the better spatiotemporal resolution of snowpack data provided by Snowcloud is beneficial in several aspects. It provides insight into snowpack evolution, and allows us to investigate differences across different spatial and temporal scales in deployment areas. It enables the relation of local variations in accumulation to environmental parameters such as slope, micro-topography and vegetation cover. The relative importance of such factors is likely to change over the snow season, for example as deposition fills depressions reducing surface roughness due to micro-topography and low lying vegetation. Snowcloud has also been deployed to support the acquisition of satellite imagery from Radarsat-2 and TanDEM-X missions. In capturing spatial variability Snowcloud provides better validation data than single node systems. An important use case of Snowcloud is its application to modeling snow-water equivalent SWE evolution, and more accurate areal average SWE estimation in locations with a typical paucity of snowpack data. We are especially interested in applying machine learning techniques to find relations between average SWE in remote areas and regional infrastructure data (e.g. regional snow pillows). These techniques leverage a combination of data provided by Snowcloud systems and periodic manual snow courses in short field campaigns. Furthermore, using machine learning we can explore the importance of snowpack variables for synthetic aperture radar backscatter at co- and cross-polarizations to better understand scattering processes and unify models of scattering with in situ observations at high resolution.

Sensor Webs as Virtual Data Systems for Earth Science

NASA Astrophysics Data System (ADS)

Moe, K. L.; Sherwood, R.

2008-05-01

The NASA Earth Science Technology Office established a 3-year Advanced Information Systems Technology (AIST) development program in late 2006 to explore the technical challenges associated with integrating sensors, sensor networks, data assimilation and modeling components into virtual data systems called "sensor webs". The AIST sensor web program was initiated in response to a renewed emphasis on the sensor web concepts. In 2004, NASA proposed an Earth science vision for a more robust Earth observing system, coupled with remote sensing data analysis tools and advances in Earth system models. The AIST program is conducting the research and developing components to explore the technology infrastructure that will enable the visionary goals. A working statement for a NASA Earth science sensor web vision is the following: On-demand sensing of a broad array of environmental and ecological phenomena across a wide range of spatial and temporal scales, from a heterogeneous suite of sensors both in-situ and in orbit. Sensor webs will be dynamically organized to collect data, extract information from it, accept input from other sensor / forecast / tasking systems, interact with the environment based on what they detect or are tasked to perform, and communicate observations and results in real time. The focus on sensor webs is to develop the technology and prototypes to demonstrate the evolving sensor web capabilities. There are 35 AIST projects ranging from 1 to 3 years in duration addressing various aspects of sensor webs involving space sensors such as Earth Observing-1, in situ sensor networks such as the southern California earthquake network, and various modeling and forecasting systems. Some of these projects build on proof-of-concept demonstrations of sensor web capabilities like the EO-1 rapid fire response initially implemented in 2003. Other projects simulate future sensor web configurations to evaluate the effectiveness of sensor-model interactions for producing improved science predictions. Still other projects are maturing technology to support autonomous operations, communications and system interoperability. This paper will highlight lessons learned by various projects during the first half of the AIST program. Several sensor web demonstrations have been implemented and resulting experience with evolving standards, such as the Open Geospatial Consortium (OGC) Sensor Web Enablement (SWE) among others, will be featured. The role of sensor webs in support of the intergovernmental Group on Earth Observations' Global Earth Observation System of Systems (GEOSS) will also be discussed. The GEOSS vision is a distributed system of systems that builds on international components to supply observing and processing systems that are, in the whole, comprehensive, coordinated and sustained. Sensor web prototypes are under development to demonstrate how remote sensing satellite data, in situ sensor networks and decision support systems collaborate in applications of interest to GEO, such as flood monitoring. Furthermore, the international Committee on Earth Observation Satellites (CEOS) has stepped up to the challenge to provide the space-based systems component for GEOSS. CEOS has proposed "virtual constellations" to address emerging data gaps in environmental monitoring, avoid overlap among observing systems, and make maximum use of existing space and ground assets. Exploratory applications that support the objectives of virtual constellations will also be discussed as a future role for sensor webs.

Application of 3D and 2D quantitative shear wave elastography (SWE) to differentiate between benign and malignant breast masses.

PubMed

Tian, Jie; Liu, Qianqi; Wang, Xi; Xing, Ping; Yang, Zhuowen; Wu, Changjun

2017-01-20

As breast cancer tissues are stiffer than normal tissues, shear wave elastography (SWE) can locally quantify tissue stiffness and provide histological information. Moreover, tissue stiffness can be observed on three-dimensional (3D) colour-coded elasticity maps. Our objective was to evaluate the diagnostic performances of quantitative features in differentiating breast masses by two-dimensional (2D) and 3D SWE. Two hundred ten consecutive women with 210 breast masses were examined with B-mode ultrasound (US) and SWE. Quantitative features of 3D and 2D SWE were assessed, including elastic modulus standard deviation (E SD E ) measured on SWE mode images and E SD U measured on B-mode images, as well as maximum elasticity (E max ). Adding quantitative features to B-mode US improved the diagnostic performance (p < 0.05) and reduced false-positive biopsies (p < 0.0001). The area under the receiver operating characteristic curve (AUC) of 3D SWE was similar to that of 2D SWE for E SD E (p = 0.026) and E SD U (p = 0.159) but inferior to that of 2D SWE for E max (p = 0.002). Compared with E SD U , E SD E showed a higher AUC on 2D (p = 0.0038) and 3D SWE (p = 0.0057). Our study indicates that quantitative features of 3D and 2D SWE can significantly improve the diagnostic performance of B-mode US, especially 3D SWE E SD E , which shows considerable clinical value.

Diagnostic accuracy of point shear wave elastography in the detection of portal hypertension in pediatric patients.

PubMed

Burak Özkan, M; Bilgici, M C; Eren, E; Caltepe, G

2018-03-01

The purpose of this study was to determine the usefulness of point shear wave elastography (p-SWE) of the liver and spleen for the detection of portal hypertension in pediatric patients. The study consisted of 38 healthy children and 56 pediatric patients with biopsy-proven liver disease who underwent splenic and liver p-SWE. The diagnostic performance of p-SWE in detecting clinically significant portal hypertension was assessed using receiver operating characteristic (ROC) curves. Reliable measurements of splenic and liver stiffness with p-SWE were obtained in 76/94 (81%) and 80/94 patients (85%), respectively. The splenic stiffness was highest in the portal hypertension group (P<0.01). At ROC curve analysis, the area under the curve in the detection of portal hypertension was lower for splenic p-SWE than for liver p-SWE (0.906 vs. 0.746; P=0.0239). The cut-off value of splenic p-SWE for portal hypertension was 3.14m/s, with a specificity of 98.59% and a sensitivity of 68.18%. The cut-off value of liver p-SWE for portal hypertension was 2.09m/s, with a specificity of 80.28% and a sensitivity of 77.27%. In pediatric patients, p-SWE is a reliable method for detecting portal hypertension. However, splenic p-SWE is less accurate than liver p-SWE for the diagnosis of portal hypertension. Copyright © 2017 Editions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

Characterization and predictability of basin scale SWE distributions using ASO snow depth and SWE retrievals

NASA Astrophysics Data System (ADS)

Bormann, K.; Hedrick, A. R.; Marks, D. G.; Painter, T. H.

2017-12-01

The spatial and temporal distribution of snow water resources (SWE) in the mountains has been examined extensively through the use of models, in-situ networks and remote sensing techniques. However, until the Airborne Snow Observatory (http://aso.jpl.nasa.gov), our understanding of SWE dynamics has been limited due to a lack of well-constrained spatial distributions of SWE in complex terrain, particularly at high elevations and at regional scales (100km+). ASO produces comprehensive snow depth measurements and well-constrained SWE products providing the opportunity to re-examine our current understanding of SWE distributions with a robust and rich data source. We collected spatially-distributed snow depth and SWE data from over 150 individual ASO acquisitions spanning seven basins in California during the five-year operational period of 2013 - 2017. For each of these acquisitions, we characterized the spatial distribution of snow depth and SWE and examined how these distributions changed with time during snowmelt. We compared these distribution patterns between each of the seven basins and finally, examined the predictability of the SWE distributions using statistical extrapolations through both space and time. We compare and contrast these observationally-based characteristics with those from a physically-based snow model to highlight the strengths and weaknesses of the implementation of our understanding of SWE processes in the model environment. In practice, these results may be used to support or challenge our current understanding of mountain SWE dynamics and provide techniques for enhanced evaluation of high-resolution snow models that go beyond in-situ point comparisons. In application, this work may provide guidance on the potential of ASO to guide backfilling of sparse spaceborne measurements of snow depth and snow water equivalent.

Shear-wave elastography and greyscale assessment of palpable probably benign masses: is biopsy always required?

PubMed

Giannotti, Elisabetta; Vinnicombe, Sarah; Thomson, Kim; McLean, Dennis; Purdie, Colin; Jordan, Lee; Evans, Andy

2016-06-01

To establish if palpable breast masses with benign greyscale ultrasound features that are soft on shear-wave elastography (SWE) (mean stiffness <50 kPa) have a low enough likelihood of malignancy to negate the need for biopsy or follow-up. The study group comprised 694 lesions in 682 females (age range 17-95 years, mean age 56 years) presenting consecutively to our institution with palpable lesions corresponding to discrete masses at ultrasound. All underwent ultrasound, SWE and needle core biopsy. Static greyscale images were retrospectively assigned Breast Imaging Reporting and Data System (BI-RADS) scores by two readers blinded to the SWE and pathology findings, but aware of the patient's age. A mean stiffness of 50 kPa was used as the SWE cut-off for calling a lesion soft or stiff. Histological findings were used to establish ground truth. No cancer had benign characteristics on both modalities. 466 (99.8%) of the 467 cancers were classified BI-RADS 4a or above. The one malignant lesion classified as BI-RADS 3 was stiff on SWE. 446 (96%) of the 467 malignancies were stiff on SWE. No cancer in females under 40 years had benign SWE features. 74 (32.6%) of the 227 benign lesions were BI-RADS 3 and soft on SWE; so, biopsy could potentially have been avoided in this group. Lesions which appear benign on greyscale ultrasound and SWE do not require percutaneous biopsy or short-term follow-up, particularly in females under 40 years. None of the cancers had benign characteristics on both greyscale ultrasound and SWE, and 32% of benign lesions were BI-RADS 3 and soft on SWE; lesions that are benign on both ultrasound and SWE may not require percutaneous biopsy or short-term follow-up.

Shear-wave elastography in the diagnosis of solid breast masses: what leads to false-negative or false-positive results?

PubMed

Yoon, Jung Hyun; Jung, Hae Kyoung; Lee, Jong Tae; Ko, Kyung Hee

2013-09-01

To investigate the factors that have an effect on false-positive or false-negative shear-wave elastography (SWE) results in solid breast masses. From June to December 2012, 222 breast lesions of 199 consecutive women (mean age: 45.3 ± 10.1 years; range, 21 to 88 years) who had been scheduled for biopsy or surgical excision were included. Greyscale ultrasound and SWE were performed in all women before biopsy. Final ultrasound assessments and SWE parameters (pattern classification and maximum elasticity) were recorded and compared with histopathology results. Patient and lesion factors in the 'true' and 'false' groups were compared. Of the 222 masses, 175 (78.8 %) were benign, and 47 (21.2 %) were malignant. False-positive rates of benign masses were significantly higher than false-negative rates of malignancy in SWE patterns, 36.6 % to 6.4 % (P < 0.001). Among both benign and malignant masses, factors showing significance among false SWE features were lesion size, breast thickness and lesion depth (all P < 0.05). All 47 malignant breast masses had SWE images of good quality. False SWE features were more significantly seen in benign masses. Lesion size, breast thickness and lesion depth have significance in producing false results, and this needs consideration in SWE image acquisition. • Shear-wave elastography (SWE) is widely used during breast imaging • At SWE, false-positive rates were significantly higher than false-negative rates • Larger size, breast thickness, depth and fair quality influences false-positive SWE features • Smaller size, larger breast thickness and depth influences false-negative SWE features.

The microbiological and immunomodulatory effects of spray-dried versus wet dietary supplementation of seaweed extract in the pig gastrointestinal tract.

PubMed

Mukhopadhya, A; O'Doherty, J V; Smith, A; Bahar, B; Sweeney, T

2012-12-01

Seaweeds and seaweed extract (SWE) possess antimicrobial, anti-inflammatory, prebiotic, and growth-promoting properties. Extracts can be prepared in different ways including wet, spray-dried, and freeze-dried forms. The aim of this study was to determine if spray drying of laminarin and fucoidan derived from Laminaria digitata had an effect on the microbiological and cytokine profile of the gastrointestinal tract (GIT) compared to the wet SWE in newly weaned pigs. No differences in cytokine expression were observed between wet and spray dried SWE formulation in either the ileum or colon. Bifidobacteria counts were greater (P < 0.05) in the wet SWE formulation relative to both spray dried SWE and the basal diet in the ileum. In conclusion, neither of the SWE formulations had significant effects on the cytokine profile in the ileum or colon. However, a prebiotic effect observed in the ileum of piglets in response to the wet SWE formulation was lost following spray drying of the SWE.

Comparison of 3D and 2D shear-wave elastography for differentiating benign and malignant breast masses: focus on the diagnostic performance.

PubMed

Choi, H Y; Sohn, Y-M; Seo, M

2017-10-01

To evaluate the diagnostic performance of three-dimensional (3D) image shear-wave elastography (SWE) for differentiating benign from malignant breast masses compared to two-dimensional (2D) SWE and B-mode ultrasound (US). This study consisted of 205 breast lesions from 199 patients who underwent B-mode US and SWE before biopsy from January 2014 to March 2016. Quantitative elasticity values (maximum and mean elasticity, Emax and Emean) obtained from 2D and 3D SWE (axial, sagittal, and coronal images) were reviewed retrospectively, in addition to the histopathological findings including immunohistochemistry profiles (luminal A, luminal B, human epidermal growth factor receptor 2 (HER2)-enriched, and triple-negative breast cancer) in cases of malignancy. Histopathological findings were regarded as the reference standard. The diagnostic performance of each data set was evaluated using the area under the receiver operating characteristic (ROC) curve (AUC) analysis to compare sensitivity and specificity. Among 205 lesions, 105 (51.22%) were malignant and 100 (48.78%) were benign. Compared to benign masses, malignant masses had higher values of Emax and Emean on both 2D and 3D SWE, the differences of which were statistically significant (p<0.001). The AUCs of 2D, 3D axial, and sagittal SWE were significantly higher than that of 3D coronal SWE (p<0.05). In addition, the sensitivities of axial, sagittal, and coronal 3D SWE were all higher than that of 2D SWE for Emean (81.9%, 87.6%, and 89.5% versus 70.5%, respectively, p<0.05). Conversely, the specificity of 2D and 3D axial SWE was higher than that of 3D sagittal and coronal SWE (Emax, 84%, 83% versus 76%, 73%; Emean, 85%, 81% versus 68%, 50%, respectively, p<0.05). We also assessed changes in Breast Imaging-Reporting and Data System (BI-RADS) category 3 and category 4a lesions by adding each of the parameters for 2D and 3D SWE in B-mode US. The specificity, PPV, and accuracy of combined 2D or combined 3D SWE with B-mode US was statistically higher than that of B-mode US alone for differentiating benign and malignant lesions (p<0.05). Among SWE images, 2D SWE, and 3D SWE axial and sagittal images exhibited superior diagnostic performance compared to 3D coronal images. Addition of 3D SWE images to B-mode US improved the diagnostic performance for distinguishing benign from malignant masses. Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Multifunctional Web Enabled Ocean Sensor Systems for the Monitoring of a Changing Ocean

NASA Astrophysics Data System (ADS)

Pearlman, Jay; Castro, Ayoze; Corrandino, Luigi; del Rio, Joaquin; Delory, Eric; Garello, Rene; Heuermann, Rudinger; Martinez, Enoc; Pearlman, Francoise; Rolin, Jean-Francois; Toma, Daniel; Waldmann, Christoph; Zielinski, Oliver

2016-04-01

As stated in the 2010 "Ostend Declaration", a major challenge in the coming years is the development of a truly integrated and sustainably funded European Ocean Observing System for supporting major policy initiatives such as the Integrated Maritime Policy and the Marine Strategy Framework Directive. This will be achieved with more long-term measurements of key parameters supported by a new generation of sensors whose costs and reliability will enable broad and consistent observations. Within the NeXOS project, a framework including new sensors capabilities and interface software has been put together that embraces the key technical aspects needed to improve the temporal and spatial coverage, resolution and quality of marine observations. The developments include new, low-cost, compact and integrated sensors with multiple functionalities that will allow for the measurements useful for a number of objectives, ranging from more precise monitoring and modeling of the marine environment to an improved assessment of fisheries. The project is entering its third year and will be demonstrating initial capabilities of optical and acoustic sensor prototypes that will become available for a number of platforms. For fisheries management, there is also a series of sensors that support an Ecosystem Approach to Fisheries (EAF). The greatest capabilities for comprehensive operations will occur when these sensors can be integrated into a multisensory capability on a single platform or multiply interconnected and coordinated platforms. Within NeXOS the full processing steps starting from the sensor signal all the way up to distributing collected environmental information will be encapsulated into standardized new state of the art Smart Sensor Interface and Web components to provide both improved integration and a flexible interface for scientists to control sensor operation. The use of the OGC SWE (Sensor Web Enablement) set of standards like OGC PUCK and SensorML at the instrument to platform integration phase will provide standard mechanisms for a truly plug'n'work connection. Through this, NeXOS Instruments will maintain within themselves specific information about how a platform (buoy controller, AUV controller, Observatory controller) has to configure and communicate with the instrument without the platform needing previous knowledge about the instrument. This mechanism is now being evaluated in real platforms like a Slocum Glider from Teledyne Web research, SeaExplorer Glider from Alseamar, Provor Float from NKE, and others including non commercial platforms like Obsea seafloor cabled observatory. The latest developments in the NeXOS sensors and the integration into an observation system will be discussed, addressing demonstration plans both for a variety of platforms and scientific objectives supporting marine management.

Deriving Snow-Cover Depletion Curves for Different Spatial Scales from Remote Sensing and Snow Telemetry Data

NASA Technical Reports Server (NTRS)

Fassnacht, Steven R.; Sexstone, Graham A.; Kashipazha, Amir H.; Lopez-Moreno, Juan Ignacio; Jasinski, Michael F.; Kampf, Stephanie K.; Von Thaden, Benjamin C.

2015-01-01

During the melting of a snowpack, snow water equivalent (SWE) can be correlated to snow-covered area (SCA) once snow-free areas appear, which is when SCA begins to decrease below 100%. This amount of SWE is called the threshold SWE. Daily SWE data from snow telemetry stations were related to SCA derived from moderate-resolution imaging spectro radiometer images to produce snow-cover depletion curves. The snow depletion curves were created for an 80,000 sq km domain across southern Wyoming and northern Colorado encompassing 54 snow telemetry stations. Eight yearly snow depletion curves were compared, and it is shown that the slope of each is a function of the amount of snow received. Snow-cover depletion curves were also derived for all the individual stations, for which the threshold SWE could be estimated from peak SWE and the topography around each station. A stations peak SWE was much more important than the main topographic variables that included location, elevation, slope, and modelled clear sky solar radiation. The threshold SWE mostly illustrated inter-annual consistency.

Preliminary Evaluation of the AFWA-NASA (ANSA) Blended Snow-Cover Product over the Lower Great Lakes Region

NASA Technical Reports Server (NTRS)

Hall, Dorothy K.; Foster, James L.; Riggs, George A.; Kelly, Richard E. J.; Chien, Janet Y. L.; Montesano, Paul M.

2009-01-01

The Air Force Weather Agency (AFWA) - NASA (ANSA) blended-snow product utilizes EOS standard snow products from the Moderate-Resolution Imaging Spectroradiometer (MODIS) and the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) to map daily snow cover and snow-water equivalent (SWE) globally. We have compared ANSA-derived SWE. with SWE values calculated from snow depths reported at approx.1500 National Climatic Data Center (NCDC) coop stations in the Lower Great Lakes basin. Our preliminary results show that conversion of snow depth to SWE is very sensitive to the choice of snow density (we used either 0.2 or 03 as conversion factors). We found overall better agreement between the ANSA-derived SWE and the co-op station data when we use a snow density of 0.3 to convert the snow depths to SWE. In addition, we show that the ANSA underestimates SWE in densely-forested areas, using January and February 2008 ANSA and co-op data. Furthermore, apparent large SWE changes from one day to the next may be caused by thaw-re-freeze events, and do not always represent a real change in SWE. In the near future we will continue the analysis in the 2006-07 and 2007-08 snow seasons.

Differentiation of benign from malignant solid breast masses: comparison of two-dimensional and three-dimensional shear-wave elastography.

PubMed

Lee, Su Hyun; Chang, Jung Min; Kim, Won Hwa; Bae, Min Sun; Cho, Nariya; Yi, Ann; Koo, Hye Ryoung; Kim, Seung Ja; Kim, Jin You; Moon, Woo Kyung

2013-04-01

To prospectively compare the diagnostic performances of two-dimensional (2D) and three-dimensional (3D) shear-wave elastography (SWE) for differentiating benign from malignant breast masses. B-mode ultrasound and SWE were performed for 134 consecutive women with 144 breast masses before biopsy. Quantitative elasticity values (maximum and mean elasticity in the stiffest portion of mass, Emax and Emean; lesion-to-fat elasticity ratio, Erat) were measured with both 2D and 3D SWE. The area under the receiver operating characteristic curve (AUC), sensitivity and specificity of B-mode, 2D, 3D SWE and combined data of B-mode and SWE were compared. Sixty-seven of the 144 breast masses (47 %) were malignant. Overall, higher elasticity values of 3D SWE than 2D SWE were noted for both benign and malignant masses. The AUC for 2D and 3D SWE were not significantly different: Emean, 0.938 vs 0.928; Emax, 0.939 vs 0.930; Erat, 0.907 vs 0.871. Either 2D or 3D SWE significantly improved the specificity of B-mode ultrasound from 29.9 % (23 of 77) up to 71.4 % (55 of 77) and 63.6 % (49 of 77) without a significant change in sensitivity. Two-dimensional and 3D SWE performed equally in distinguishing benign from malignant masses and both techniques improved the specificity of B-mode ultrasound.

Large scale snow water status monitoring: comparison of different snow water products in the upper Colorado basins

USGS Publications Warehouse

Artan, G.A.; Verdin, J.P.; Lietzow, R.

2013-01-01

We illustrate the ability to monitor the status of snowpack over large areas by using a~spatially distributed snow accumulation and ablation model in the Upper Colorado Basin. The model was forced with precipitation fields from the National Weather Service (NWS) Multi-sensor Precipitation Estimator (MPE) and the Tropical Rainfall Measuring Mission (TRMM) datasets; remaining meteorological model input data was from NOAA's Global Forecast System (GFS) model output fields. The simulated snow water equivalent (SWE) was compared to SWEs from the Snow Data Assimilation System (SNODAS) and SNOwpack TELemetry system (SNOTEL) over a~region of the Western United States that covers parts of the Upper Colorado Basin. We also compared the SWE product estimated from the Special Sensor Microwave Imager (SSM/I) and Scanning Multichannel Microwave Radiometer (SMMR) to the SNODAS and SNOTEL SWE datasets. Agreement between the spatial distribution of the simulated SWE with both SNODAS and SNOTEL was high for the two model runs for the entire snow accumulation period. Model-simulated SWEs, both with MPE and TRMM, were significantly correlated spatially on average with the SNODAS (r = 0.81 and r = 0.54; d.f. = 543) and the SNOTEL SWE (r = 0.85 and r = 0.55; d.f. = 543), when monthly basinwide simulated average SWE the correlation was also highly significant (r = 0.95 and r = 0.73; d.f. = 12). The SWE estimated from the passive microwave imagery was not correlated either with the SNODAS SWE or (r = 0.14, d.f. = 7) SNOTEL-reported SWE values (r = 0.08, d.f. = 7). The agreement between modeled SWE and the SWE recorded by SNODAS and SNOTEL weakened during the snowmelt period due to an underestimation bias of the air temperature that was used as model input forcing.

Validation of Globsnow-2 Snow Water Equivalent Over Eastern Canada

NASA Technical Reports Server (NTRS)

Larue, Fanny; Royer, Alain; De Seve, Danielle; Langlois, Alexandre; Roy, Alexandre R.; Brucker, Ludovic

2017-01-01

In Qubec, Eastern Canada, snowmelt runoff contributes more than 30% of the annual energy reserve for hydroelectricity production, and uncertainties in annual maximum snow water equivalent (SWE) over the region are one of the main constraints for improved hydrological forecasting. Current satellite-based methods for mapping SWE over Qubec's main hydropower basins do not meet Hydro-Qubec operational requirements for SWE accuracies with less than 15% error. This paper assesses the accuracy of the GlobSnow-2 (GS-2) SWE product, which combines microwave satellite data and in situ measurements, for hydrological applications in Qubec. GS-2 SWE values for a 30-year period (1980 to 2009) were compared with space- and time-matched values from a comprehensive dataset of in situ SWE measurements (a total of 38,990 observations in Eastern Canada). The root mean square error (RMSE) of the GS-2 SWE product is 94.1+/- 20.3 mm, corresponding to an overall relative percentage error (RPE) of 35.9%. The main sources of uncertainty are wet and deep snow conditions (when SWE is higher than 150 mm), and forest cover type. However, compared to a typical stand-alone brightness temperature channel difference algorithm, the assimilation of surface information in the GS-2 algorithm clearly improves SWE accuracy by reducing the RPE by about 30%. Comparison of trends in annual mean and maximum SWE between surface observations and GS-2 over 1980-2009 showed agreement for increasing trends over southern Qubec, but less agreement on the sign and magnitude of trends over northern Qubec. Extended at a continental scale, the GS-2 SWE trends highlight a strong regional variability.

Shear wave elastography in the diagnosis of breast non-mass lesions: factors associated with false negative and false positive results.

PubMed

Park, So Yoon; Choi, Ji Soo; Han, Boo-Kyung; Ko, Eun Young; Ko, Eun Sook

2017-09-01

To investigate factors related to false shear wave elastography (SWE) results for breast non-mass lesions (NMLs) detected by B-mode US. This retrospective study enrolled 152 NMLs detected by B-mode US and later pathologically confirmed (79 malignant, 73 benign). All lesions underwent B-mode US and SWE. Quantitative (mean elasticity [E mean ]) and qualitative (maximum stiffness colour) SWE parameters were assessed, and 'E mean  > 85.1 kPa' or 'stiff colour (green to red)' determined malignancy. Final SWE results were matched to pathology results. Multivariate logistic regression analysis identified factors associated with false SWE results for diagnosis of breast NMLs. Associated calcifications (E mean : odds ratio [OR] = 7.60, P < 0.01; maximum stiffness colour: OR = 6.30, P = 0.02), in situ cancer compared to invasive cancer (maximum stiffness colour: OR = 5.29, P = 0.02), and lesion size (E mean : OR = 0.90, P < 0.01; maximum stiffness colour: OR = 0.91, P = 0.01) were significantly associated with false negative SWE results for malignant NMLs. Distance from the nipple (E mean : OR = 0.84, P = 0.03; maximum stiffness colour: OR = 0.93, P = 0.04) was significantly associated with false positive SWE results for benign NMLs. Presence of associated calcifications, absence of the invasive component, and smaller lesion size for malignant NMLs and shorter distance from the nipple for benign NMLs are factors significantly associated with false SWE results. • Calcification and size are associated with false negative SWE in malignant NMLs. • In situ cancer is associated with false negative SWE in malignant NMLs. • Distance from the nipple is associated with false positive SWE in benign NMLs. • These factors need consideration when performing SWE on breast NMLs.

Two-View versus Single-View Shear-Wave Elastography: Comparison of Observer Performance in Differentiating Benign from Malignant Breast Masses.

PubMed

Lee, Su Hyun; Cho, Nariya; Chang, Jung Min; Koo, Hye Ryoung; Kim, Jin You; Kim, Won Hwa; Bae, Min Sun; Yi, Ann; Moon, Woo Kyung

2013-10-28

Purpose To determine whether two-view shear-wave elastography (SWE) improves the performance of radiologists in differentiating benign from malignant breast masses compared with single-view SWE. Materials and Methods This prospective study was conducted with institutional review board approval, and written informed consent was obtained. B-mode ultrasonographic (US) and orthogonal SWE images were obtained for 219 breast masses (136 benign and 83 malignant; mean size, 14.8 mm) in 219 consecutive women (mean age, 47.9 years; range, 20-78 years). Five blinded radiologists independently assessed the likelihood of malignancy for three data sets: B-mode US alone, B-mode US and single-view SWE, and B-mode US and two-view SWE. Interobserver agreement regarding Breast Imaging Reporting and Data System (BI-RADS) category and the area under the receiver operating characteristic curve (AUC) of each data set were compared. Results Interobserver agreement was moderate (κ = 0.560 ± 0.015 [standard error of the mean]) for BI-RADS category assessment with B-mode US alone. When SWE was added to B-mode US, five readers showed substantial interobserver agreement (κ = 0.629 ± 0.017 for single-view SWE; κ = 0.651 ± 0.014 for two-view SWE). The mean AUC of B-mode US was 0.870 (range, 0.855-0.884). The AUC of B-mode US and two-view SWE (average, 0.928; range, 0.904-0.941) was higher than that of B-mode US and single-view SWE (average, 0.900; range, 0.890-0.920), with statistically significant differences for three readers (P ≤ .003). Conclusion The performance of radiologists in differentiating benign from malignant breast masses was improved when B-mode US was combined with two-view SWE compared with that when B-mode US was combined with single-view SWE. © RSNA, 2013 Supplemental material: S1.

Two-view versus single-view shear-wave elastography: comparison of observer performance in differentiating benign from malignant breast masses.

PubMed

Lee, Su Hyun; Cho, Nariya; Chang, Jung Min; Koo, Hye Ryoung; Kim, Jin You; Kim, Won Hwa; Bae, Min Sun; Yi, Ann; Moon, Woo Kyung

2014-02-01

To determine whether two-view shear-wave elastography (SWE) improves the performance of radiologists in differentiating benign from malignant breast masses compared with single-view SWE. This prospective study was conducted with institutional review board approval, and written informed consent was obtained. B-mode ultrasonographic (US) and orthogonal SWE images were obtained for 219 breast masses (136 benign and 83 malignant; mean size, 14.8 mm) in 219 consecutive women (mean age, 47.9 years; range, 20-78 years). Five blinded radiologists independently assessed the likelihood of malignancy for three data sets: B-mode US alone, B-mode US and single-view SWE, and B-mode US and two-view SWE. Interobserver agreement regarding Breast Imaging Reporting and Data System (BI-RADS) category and the area under the receiver operating characteristic curve (AUC) of each data set were compared. Interobserver agreement was moderate (κ = 0.560 ± 0.015 [standard error of the mean]) for BI-RADS category assessment with B-mode US alone. When SWE was added to B-mode US, five readers showed substantial interobserver agreement (κ = 0.629 ± 0.017 for single-view SWE; κ = 0.651 ± 0.014 for two-view SWE). The mean AUC of B-mode US was 0.870 (range, 0.855-0.884). The AUC of B-mode US and two-view SWE (average, 0.928; range, 0.904-0.941) was higher than that of B-mode US and single-view SWE (average, 0.900; range, 0.890-0.920), with statistically significant differences for three readers (P ≤ .003). The performance of radiologists in differentiating benign from malignant breast masses was improved when B-mode US was combined with two-view SWE compared with that when B-mode US was combined with single-view SWE. © RSNA, 2013

Shear wave elastography for breast masses is highly reproducible.

PubMed

Cosgrove, David O; Berg, Wendie A; Doré, Caroline J; Skyba, Danny M; Henry, Jean-Pierre; Gay, Joel; Cohen-Bacrie, Claude

2012-05-01

To evaluate intra- and interobserver reproducibility of shear wave elastography (SWE) for breast masses. For intraobserver reproducibility, each observer obtained three consecutive SWE images of 758 masses that were visible on ultrasound. 144 (19%) were malignant. Weighted kappa was used to assess the agreement of qualitative elastographic features; the reliability of quantitative measurements was assessed by intraclass correlation coefficients (ICC). For the interobserver reproducibility, a blinded observer reviewed images and agreement on features was determined. Mean age was 50 years; mean mass size was 13 mm. Qualitatively, SWE images were at least reasonably similar for 666/758 (87.9%). Intraclass correlation for SWE diameter, area and perimeter was almost perfect (ICC ≥ 0.94). Intraobserver reliability for maximum and mean elasticity was almost perfect (ICC = 0.84 and 0.87) and was substantial for the ratio of mass-to-fat elasticity (ICC = 0.77). Interobserver agreement was moderate for SWE homogeneity (κ = 0.57), substantial for qualitative colour assessment of maximum elasticity (κ = 0.66), fair for SWE shape (κ = 0.40), fair for B-mode mass margins (κ = 0.38), and moderate for B-mode mass shape (κ = 0.58), orientation (κ = 0.53) and BI-RADS assessment (κ = 0.59). SWE is highly reproducible for assessing elastographic features of breast masses within and across observers. SWE interpretation is at least as consistent as that of BI-RADS ultrasound B-mode features. • Shear wave ultrasound elastography can measure the stiffness of breast tissue • It provides a qualitatively and quantitatively interpretable colour-coded map of tissue stiffness • Intraobserver reproducibility of SWE is almost perfect while intraobserver reproducibility of SWE proved to be moderate to substantial • The most reproducible SWE features between observers were SWE image homogeneity and maximum elasticity.

Voluntary Field Data Collection for Landscape Phenology and Surface Water Essential Climate Variable Research

NASA Astrophysics Data System (ADS)

Jones, J. W.; Hudson-Dunn, A.; Aquino, K.; Pasa, M.; Paez, F.

2013-12-01

The U.S. Geological Survey is developing techniques to monitor vegetation and surface water condition for improved resource management. Educational materials and data forms that allow volunteer Citizen Scientists to collect information on vegetation and surface water extent to enhance satellite and web camera data analyses (http://egsc.usgs.gov/shenandoah.html) have been developed, tested, and refined. Collection is focused on supplementing landscape phenology and surface water extent (SWE) essential climate variable (ECV) research. Low cost instrumentation, subject education, and measurement calibration techniques all have utility for multiple remote sensing and biophysical studies. Trials have been conducted with subjects ranging from elementary school-aged summer camp children to science major undergraduate and graduate students. Experiments were replicated in several project study areas in Virginia that are also phenology and SWE-ECV research sites. Analysis of volunteer responses and their narrative feedback have improved the ability to request and assess data from volunteers. Children ages 12 and over were able to provide reliable supplemental information for phenology and aquatic research. Finally, trial observation and subject feedback both confirmed that participation furthered volunteer interest in science.

Using ground penetrating radar to assess the variability of snow water equivalent and melt in a mixed canopy forest, Northern Colorado

NASA Astrophysics Data System (ADS)

Webb, Ryan W.

2017-09-01

Snow is an important environmental variable in headwater systems that controls hydrological processes such as streamflow, groundwater recharge, and evapotranspiration. These processes will be affected by both the amount of snow available for melt and the rate at which it melts. Snow water equivalent (SWE) and snowmelt are known to vary within complex subalpine terrain due to terrain and canopy influences. This study assesses this variability during the melt season using ground penetrating radar to survey multiple plots in northwestern Colorado near a snow telemetry (SNOTEL) station. The plots include south aspect and flat aspect slopes with open, coniferous (subalpine fir, Abies lasiocarpa and engelman spruce, Picea engelmanii), and deciduous (aspen, populous tremuooides) canopy cover. Results show the high variability for both SWE and loss of SWE during spring snowmelt in 2014. The coefficient of variation for SWE tended to increase with time during snowmelt whereas loss of SWE remained similar. Correlation lengths for SWE were between two and five meters with melt having correlation lengths between two and four meters. The SNOTEL station regularly measured higher SWE values relative to the survey plots but was able to reasonably capture the overall mean loss of SWE during melt. Ground Penetrating Radar methods can improve future investigations with the advantage of non-destructive sampling and the ability to estimate depth, density, and SWE.

Acquisition system for the "EMSO Generic Instrument Module" (EGIM) and analysis of the data obtained during its first deployment at OBSEA site (Spain)

NASA Astrophysics Data System (ADS)

Garcia, Oscar; Mihai Toma, Daniel; Dañobeitia, Juanjo; del Rio, Joaquin; Bartolome, Rafael; Martínez, Enoc; Nogueras, Marc; Bghiel, Ikram; Lanteri, Nadine; Rolin, Jean Francois; Beranzoli, Laura; Favali, Paolo

2017-04-01

The EMSODEV project (EMSO implementation and operation: DEVelopment of instrument module) is an Horizon-2020 UE project whose overall objective is the operation of eleven seafloor observatories and four test sites. These infrastructures are distributed throughout European seas, from the Arctic across the Atlantic and the Mediterranean to the Black Sea, and are managed by the European consortium EMSO-ERIC (European Research Infrastructure Consortium) with the participation of 8 European countries and other associated partners. Recently, we have implemented a Generic Sensor Module (EGIM) within the EMSO-ERIC distributed marine research infrastructure. EGIM is able to operate on any EMSO observatory node, mooring line, seabed station, cabled or non-cabled and surface buoy. The main role of EGIM is to measure homogeneously a set of core variables using the same hardware, sensor references, qualification methods, calibration methods, data format and access, maintenance procedures in several European ocean locations. The EGIM module acquires a wide range of ocean parameters in a long-term consistent, accurate and comparable manner from disciplines such as biology, geology, chemistry, physics, engineering, and computer science, from polar to subtropical environments, through the water column down to the deep sea. Our work includes developing standard-compliant generic software for Sensor Web Enablement (SWE) on EGIM and to perform the first onshore and offshore test bench, to support the sensors data acquisition on a new interoperable EGIM system. EGIM in its turn is linked to an acquisition drives processes, a centralized Sensor Observation Service (SOS) server and a laboratory monitor system (LabMonitor) that records events and alarms during acquisition. The measurements recorded along EMSO NODES are essential to accurately respond to the social and scientific challenges such as climate change, changes in marine ecosystems, and marine hazards. This presentation shows the first EGIM deployment and the SWE infrastructure, developed to manage the data acquisition from the underwater sensors and their insertion to the SOS interface.

Snow water equivalent determination by microwave radiometry

NASA Technical Reports Server (NTRS)

Chang, A. T. C.; Foster, J. L.; Hall, D. K.; Rango, A.; Hartline, B. K.

1981-01-01

One of the most important parameters for accurate snowmelt runoff prediction is snow water equivalent (SWE) which is contentionally monitored using observations made at widely scattered points in or around specific watersheds. Remote sensors which provide data with better spatial and temporal coverage can be used to improve the SWE estimates. Microwave radiation, which can penetrate through a snowpack, may be used to infer the SWE. Calculations made from a microscopic scattering model were used to simulate the effect of varying SWE on the microwave brightness temperature. Data obtained from truck mounted, airborne and spaceborne systems from various test sites were studied. The simulated SWE compares favorable with the measured SWE. In addition, whether the underlying soil is frozen or thawed can be discriminated successfully on the basis of the polarization of the microwave radiation.

Assessment of liver fibrosis in chronic hepatitis: comparison of shear wave elastography and transient elastography.

PubMed

Paul, Shashi B; Das, Prasenjit; Mahanta, Mousumi; Sreenivas, Vishnubhatla; Kedia, Saurabh; Kalra, Nancy; Kaur, Harpreet; Vijayvargiya, Maneesh; Ghosh, Shouriyo; Gamanagatti, Shivanand R; Shalimar; Gupta, Siddhartha Dutta; Acharya, Subrat K

2017-12-01

To evaluate the diagnostic accuracy of shear wave elastography (SWE) and transient elastography (TE) in the evaluation of liver fibrosis in chronic hepatitis B (CHB) and C (CHC) patients taking liver biopsy as gold standard. Ethics committee approved this prospective cross-sectional study. Between October 2012 and December 2014, consecutive CHB/CHC patients fulfilling the inclusion criteria were included-age more than 18 years, informed written consent, willing and suitable for liver biopsy. SWE, TE, and biopsy were performed the same day. Liver stiffness measurement (LSM) cut-offs for various stages of fibrosis were generated for SWE and TE. AUC, sensitivity, specificity, and positive/negative predictive values were estimated individually or in combination. CH patients (n = 240, CHB 172, CHC 68), 176 males, 64 females, mean age 32.6 ± 11.6 years were enrolled. Mean LSM of patients with no histological fibrosis (F0) was 5.0 ± 0.7 and 5.1+1.4 kPa on SWE and TE, respectively. For differentiating F2 and F3-4 fibrosis on SWE, at 7.0 kPa cut-off, the sensitivity was 81.3% and specificity 77.6%. For TE, at 8.3 kPa cut-off, sensitivity was 81.8% and specificity 83.1%. For F3 vs. F4, SWE sensitivity was 83.3% and specificity 90.7%. At 14.8 kPa cut-off, TE showed similar sensitivity (83.3%) but specificity increased to 96.5%. Significant correlation between SWE and TE was observed (r = 0.33, p < 0.001). On combining SWE and TE, a drop in sensitivity with increased specificity for all stages of liver fibrosis occured. SWE is an accurate technique for evaluating liver fibrosis. SWE compares favorably with TE especially for predicting advanced fibrosis/cirrhosis. Combining SWE and TE further improves specificity.

Reliability of shear wave ultrasound elastography for neck lesions identified in routine clinical practice.

PubMed

Bhatia, K; Tong, C S L; Cho, C C M; Yuen, E H Y; Lee, J; Ahuja, A T

2012-10-01

To evaluate the reliability of shear wave ultrasound elastography (SWE) in the neck. 176 neck lesions (40 thyroid, 56 lymph nodes, 46 salivary, 34 miscellaneous) identified in a routine US clinic underwent SWE by one or two blinded radiologists. For this study, SWE required the operator to acquire three 10 second dynamic colour-coded SWE cineloops per lesion, select one static image per cineloop, and place circular regions-of-interest within the entire lesion and stiffest part to generate 3 SWE measurements per static image. For logistical reasons, one radiologist evaluated all 176 lesions and the other evaluated 58 lesions. Both radiologists also reviewed 27 archived cineloops independently to assess SWE excluding practical technique. Reliability was assessed using intraclass correlation coefficients (ICCs) concordance correlation coefficients (CCCs) and coefficients of repeatability (CORs). Test-retest ICCs for the radiologist evaluating 176 lesions were 0.78 - 0.85 (fair-excellent agreement), CCCs were 0.85 - 0.88 (substantial agreement), and CORs were 14.9 - 36.1 kPa. For both radiologists evaluating 58 lesions, intra-rater and inter-rater ICCs were 0.65 - 0.78 and 0.72 - 0.77 respectively. For SWE excluding practical technique, inter-rater ICCs were 0.97 - 0.98 (excellent agreement). ICCs differed according to tissue, being higher in thyroid lesions than lymph nodes (p < 0.001), and higher in benign than malignant lesions (p values < 0.001). Intra- and inter-rater reliability of SWE is fair to excellent according to ICCs. SWE reliability is influenced appreciably by acquisition technique. Nevertheless, CORs for SWE are not negligible. To determine whether these results are acceptable clinically, further research is required to establish SWE stiffness values of normal and pathological tissues in the neck. © Georg Thieme Verlag KG Stuttgart · New York.

Diagnostic performances of shear wave elastography: which parameter to use in differential diagnosis of solid breast masses?

PubMed

Lee, Eun Jung; Jung, Hae Kyoung; Ko, Kyung Hee; Lee, Jong Tae; Yoon, Jung Hyun

2013-07-01

To evaluate which shear wave elastography (SWE) parameter proves most accurate in the differential diagnosis of solid breast masses. One hundred and fifty-six breast lesions in 139 consecutive women (mean age: 43.54 ± 9.94 years, range 21-88 years), who had been scheduled for ultrasound-guided breast biopsy, were included. Conventional ultrasound and SWE were performed in all women before biopsy procedures. Ultrasound BI-RADS final assessment and SWE parameters were recorded. Diagnostic performance of each SWE parameter was calculated and compared with those obtained when applying cut-off values of previously published data. Performance of conventional ultrasound and ultrasound combined with each parameter was also compared. Of the 156 breast masses, 120 (76.9 %) were benign and 36 (23.1 %) malignant. Maximum stiffness (Emax) with a cut-off of 82.3 kPa had the highest area under the receiver operating characteristics curve (Az) value compared with other SWE parameters, 0.860 (sensitivity 88.9 %, specificity 77.5 %, accuracy 80.1 %). Az values of conventional ultrasound combined with each SWE parameter showed lower (but not significantly) values than with conventional ultrasound alone. Maximum stiffness (82.3 kPa) provided the best diagnostic performance. However the overall diagnostic performance of ultrasound plus SWE was not significantly better than that of conventional ultrasound alone. • SWE offers new information over and above conventional breast ultrasound • Various SWE parameters were explored regarding distinction between benign and malignant lesions • An elasticity of 82.3 kPa appears optimal in differentiating solid breast masses • However, ultrasound plus SWE was not significantly better than conventional ultrasound alone.

False positive or negative results of shear-wave elastography in differentiating benign from malignant breast masses: analysis of clinical and ultrasonographic characteristics.

PubMed

Kim, Mi Young; Choi, Nami; Yang, Jung-Hyun; Yoo, Young Bum; Park, Kyoung Sik

2015-10-01

Shear-wave elastography (SWE) has the potential to improve diagnostic performance of conventional ultrasound (US) in differentiating benign from malignant breast masses. To investigate false positive or negative results of SWE in differentiating benign from malignant breast masses and to analyze clinical and imaging characteristics of the masses with false SWE findings. From May to October 2013, 166 breast lesions of 164 consecutive women (mean age, 45.3 ± 10.1 years) who had been scheduled for biopsy were included. Conventional US and SWE were performed in all women before biopsy. Clinical, ultrasonographic morphologic features and SWE parameters (pattern classification and standard deviation [SD]) were recorded and compared with the histopathology results. Patient and lesion factors in the "true" and "false" groups were compared. Of the 166 masses, 118 (71.1%) were benign and 48 (28.9%) were malignant. False SWE features were more frequently observed in benign masses. False positive rates of benign masses and false negative rates of malignancy were 53% and 8.2%, respectively, using SWE pattern analysis and were 22.4% and 10.3%, respectively, using SD values. A lesion boundary of the masses on US (P = 0.039) and younger patient age (P = 0.047) were significantly associated with false SWE findings. These clinical and ultrasonographic features need to be carefully evaluated in performance and interpretation of SWE examinations. © The Foundation Acta Radiologica 2014.

Shear-Wave Elastography for the Differential Diagnosis of Breast Papillary Lesions

PubMed Central

Chung, Jin; Lee, Won Kyung; Cha, Eun-Suk; Lee, Jee Eun; Kim, Jeoung Hyun; Ryu, Young Hoon

2016-01-01

Objective To evaluate the diagnostic performance of shear-wave elastography (SWE) for the differential diagnosis of breast papillary lesions. Methods This study was an institutional review board-approved retrospective study, with a waiver of informed consent. A total of 79 breast papillary lesions in 71 consecutive women underwent ultrasound and SWE prior to biopsy. Ultrasound features and quantitative SWE parameters were recorded for each lesion. All lesions were surgically excised or excised using an ultrasound-guided vacuum-assisted method. The diagnostic performances of the quantitative SWE parameters were compared using the area under the receiver operating characteristic curve (AUC). Results Of the 79 lesions, six (7.6%) were malignant and 12 (15.2%) were atypical. Orientation, margin, and the final BI-RADS ultrasound assessments were significantly different for the papillary lesions (p < 0.05). All qualitative SWE parameters were significantly different (p < 0.05). The AUC values for SWE parameters of benign and atypical or malignant papillary lesions ranged from 0.707 to 0.757 (sensitivity, 44.4–94.4%; specificity, 42.6–88.5%). The maximum elasticity and the mean elasticity showed the highest AUC (0.757) to differentiate papillary lesions. Conclusion SWE provides additional information for the differential diagnosis of breast papillary lesions. Quantitative SWE features were helpful to differentiate breast papillary lesions. PMID:27893857

SCHeMA web-based observation data information system

NASA Astrophysics Data System (ADS)

Novellino, Antonio; Benedetti, Giacomo; D'Angelo, Paolo; Confalonieri, Fabio; Massa, Francesco; Povero, Paolo; Tercier-Waeber, Marie-Louise

2016-04-01

It is well recognized that the need of sharing ocean data among non-specialized users is constantly increasing. Initiatives that are built upon international standards will contribute to simplify data processing and dissemination, improve user-accessibility also through web browsers, facilitate the sharing of information across the integrated network of ocean observing systems; and ultimately provide a better understanding of the ocean functioning. The SCHeMA (Integrated in Situ Chemical MApping probe) Project is developing an open and modular sensing solution for autonomous in situ high resolution mapping of a wide range of anthropogenic and natural chemical compounds coupled to master bio-physicochemical parameters (www.schema-ocean.eu). The SCHeMA web system is designed to ensure user-friendly data discovery, access and download as well as interoperability with other projects through a dedicated interface that implements the Global Earth Observation System of Systems - Common Infrastructure (GCI) recommendations and the international Open Geospatial Consortium - Sensor Web Enablement (OGC-SWE) standards. This approach will insure data accessibility in compliance with major European Directives and recommendations. Being modular, the system allows the plug-and-play of commercially available probes as well as new sensor probess under development within the project. The access to the network of monitoring probes is provided via a web-based system interface that, being implemented as a SOS (Sensor Observation Service), is providing standard interoperability and access tosensor observations systems through O&M standard - as well as sensor descriptions - encoded in Sensor Model Language (SensorML). The use of common vocabularies in all metadatabases and data formats, to describe data in an already harmonized and common standard is a prerequisite towards consistency and interoperability. Therefore, the SCHeMA SOS has adopted the SeaVox common vocabularies populated by SeaDataNet network of National Oceanographic Data Centres. The SCHeMA presentation layer, a fundamental part of the software architecture, offers to the user a bidirectional interaction with the integrated system allowing to manage and configure the sensor probes; view the stored observations and metadata, and handle alarms. The overall structure of the web portal developed within the SCHeMA initiative (Sensor Configuration, development of Core Profile interface for data access via OGC standard, external services such as web services, WMS, WFS; and Data download and query manager) will be presented and illustrated with examples of ongoing tests in costal and open sea.

Diagnostic performance of qualitative shear-wave elastography according to different color map opacities for breast masses.

PubMed

Kim, Hana; Youk, Ji Hyun; Gweon, Hye Mi; Kim, Jeong-Ah; Son, Eun Ju

2013-08-01

To compare the diagnostic performance of qualitative shear-wave elastography (SWE) according to three different color map opacities for breast masses 101 patients aged 21-77 years with 113 breast masses underwent B-mode US and SWE under three different color map opacities (50%, 19% and 100%) before biopsy or surgery. Following SWE features were reviewed: visual pattern classification (pattern 1-4), color homogeneity (Ehomo) and six-point color score of maximum elasticity (Ecol). Combined with B-mode US and SWE, the likelihood of malignancy (LOM) was also scored. The area under the curve (AUC) was obtained by ROC curve analysis to assess the diagnostic performance under each color opacity. A visual color pattern, Ehomo, Ecol and LOM scoring were significantly different between benign and malignant lesions under all color opacities (P<0.001). For 50% opacity, AUCs of visual color pattern, Ecol, Ehomo and LOM scoring were 0.902, 0.951, 0.835 and 0.975. But, for each SWE feature, there was no significant difference in the AUC among three different color opacities. For all color opacities, visual color pattern and Ecol showed significantly higher AUC than Ehomo. In addition, a combined set of B-mode US and SWE showed significantly higher AUC than SWE alone for color patterns, Ehomo, but no significant difference was found in Ecol. Qualitative SWE was useful to differentiate benign from malignant breast lesion under all color opacities. The difference in color map opacity did not significantly influence diagnostic performance of SWE. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Evaluation of Liver Stiffness After Radioembolization by Real-Time ShearWave™ Elastography: Preliminary Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bas, Ahmet, E-mail: dr.ahmetbas@hotmail.com; Samanci, Cesur, E-mail: cesursamanci@gmail.com; Gulsen, Fatih, E-mail: drfgulsen@yahoo.com

2015-08-15

PurposeTo evaluate the effect of ShearWave™ elastography (SWE) for the assessment of liver fibrosis after radioembolization (RE) in patients with liver malignancies.Materials and MethodsWe prospectively examined the effects of SWE before and after RE in 17 adult patients, from June 2012 to September 2013. All patients underwent SWE within 1 month before and 3 months (96.3 ± 22.9 days) after RE. Measurements were taken in segments III, IV, V, and VI (lateral/medial left lobe and anterior/posterior right lobe, respectively). Liver stiffness was studied in the 39 treated segments.ResultsThe mean stiffness of liver tissue according to the pre-RE SWE measurements was not different from the post-REmore » SWE measurements in the segments that did not undergo RE. Conversely, segments treated with RE were significantly stiffer according to the post-RE SWE measurements (mean SWE 17.4 kPa) than according to the baseline measurements (7.0 kPa) (p < 0.001). Patients with hepatocellular carcinoma and preexisting infection with hepatitis B and C viruses had higher pre-embolization stiffness, and the post-embolization stiffness of the treated segments in these patients was higher than that in the remainder of the study population.ConclusionThese data suggest that SWE measurements of liver stiffness increase as early as the third month after RE. SWE could be used as a noninvasive complementary imaging method for preliminary assessment of liver fibrosis before and after RE.« less

Effect of maternal supplementation with seaweed extracts on growth performance and aspects of gastrointestinal health of newly weaned piglets after challenge with enterotoxigenic Escherichia coli K88.

PubMed

Heim, G; Sweeney, T; O'Shea, C J; Doyle, D N; O'Doherty, J V

2014-12-28

In the present study, a 2 × 2 factorial arrangement was conducted to investigate the effect of maternal supplementation with seaweed extracts ( - SWE v. +SWE, n 20) from day 83 of gestation until weaning (day 28) on post-weaning (PW) growth performance, faecal score, faecal enterotoxigenic Escherichia coli (ETEC) toxin quantification, intestinal histology and cytokine mRNA of unchallenged and ETEC-challenged pigs. Pigs were ETEC challenged on day 9 PW. There was a maternal treatment × challenge (SWE × ETEC) interaction effect on growth performance and faecal score (P< 0.05). Pigs from SWE-supplemented sows and ETEC-challenged (SE) had higher average daily gain (ADG) during 0-13 d PW and reduced faecal score during 0-72 h post-challenge than those from basal-fed sows and ETEC-challenged (BE) (P< 0.05). However, there was no difference between unchallenged pigs from the SWE-supplemented sows (SC) and basal-fed sows (BC) (P>0.10). Pigs from the SWE-supplemented sows had reduced heat-labile enterotoxin gene copy numbers than those from the basal-fed sows (P< 0.05). Maternal SWE supplementation increased the villus height in the ileum of pigs (P< 0.05). There was a SWE × ETEC interaction effect (P< 0.05) on IL-6 mRNA and a SWE × gastrointestinal (GI) region interaction effect (P< 0.05) on transforming growth factor-β1 (TGF-β1) and TNF-α mRNA. IL-6 mRNA was down-regulated in SC pigs than BC pigs (P< 0.05). However, there was no difference in IL-6 mRNA between SE and BE pigs. The mRNA of TGF-β1 and TNF-α was down-regulated in the colon of pigs from the SWE-supplemented sows compared with those from the basal-fed sows (P< 0.05). However, there was no difference in TGF-β1 and TNF-α mRNA in the ileum between the pigs from the SWE-supplemented sows and basal-fed sows. In conclusion, maternal SWE supplementation improves ADG and the aspects of GI health of weaned pigs following an ETEC challenge.

The tsunami service bus, an integration platform for heterogeneous sensor systems

NASA Astrophysics Data System (ADS)

Haener, R.; Waechter, J.; Kriegel, U.; Fleischer, J.; Mueller, S.

2009-04-01

1. INTRODUCTION Early warning systems are long living and evolving: New sensor-systems and -types may be developed and deployed, sensors will be replaced or redeployed on other locations and the functionality of analyzing software will be improved. To ensure a continuous operability of those systems their architecture must be evolution-enabled. From a computer science point of view an evolution-enabled architecture must fulfill following criteria: • Encapsulation of and functionality on data in standardized services. Access to proprietary sensor data is only possible via these services. • Loose coupling of system constituents which easily can be achieved by implementing standardized interfaces. • Location transparency of services what means that services can be provided everywhere. • Separation of concerns that means breaking a system into distinct features which overlap in functionality as little as possible. A Service Oriented Architecture (SOA) as e. g. realized in the German Indonesian Tsunami Early Warning System (GITEWS) and the advantages of functional integration on the basis of services described below adopt these criteria best. 2. SENSOR INTEGRATION Integration of data from (distributed) data sources is just a standard task in computer science. From few well known solution patterns, taking into account performance and security requirements of early warning systems only functional integration should be considered. Precondition for this is that systems are realized compliant to SOA patterns. Functionality is realized in form of dedicated components communicating via a service infrastructure. These components provide their functionality in form of services via standardized and published interfaces which could be used to access data maintained in - and functionality provided by dedicated components. Functional integration replaces the tight coupling at data level by a dependency on loosely coupled services. If the interfaces of the service providing components remain unchanged, components can be maintained and evolved independently on each other and service functionality as a whole can be reused. In GITEWS the functional integration pattern was adopted by applying the principles of an Enterprise Service Bus (ESB) as a backbone. Four services provided by the so called Tsunami Service Bus (TSB) which are essential for early warning systems are realized compliant to services specified within the Sensor Web Enablement (SWE) initiative of the Open Geospatial Consortium (OGC). 3. ARCHITECTURE The integration platform was developed to access proprietary, heterogeneous sensor data and to provide them in a uniform manner for further use. Its core, the TSB provides both a messaging-backbone and -interfaces on the basis of a Java Messaging Service (JMS). The logical architecture of GITEWS consists of four independent layers: • A resource layer where physical or virtual sensors as well as data or model storages provide relevant measurement-, event- and analysis-data: Utilizable for the TSB are any kind of data. In addition to sensors databases, model data and processing applications are adopted. SWE specifies encoding both to access and to describe these data in a comprehensive way: 1. Sensor Model Language (SensorML): Standardized description of sensors and sensor data 2. Observations and Measurements (O&M): Model and encoding of sensor measurements • A service layer to collect and conduct data from heterogeneous and proprietary resources and provide them via standardized interfaces: The TSB enables interaction with sensors via the following services: 1. Sensor Observation Service (SOS): Standardized access to sensor data 2. Sensor Planning Service (SPS): Controlling of sensors and sensor networks 3. Sensor Alert Service (SAS): Active sending of data if defined events occur 4. Web Notification Service (WNS): Conduction of asynchronous dialogues between services • An orchestration layer where atomic services are composed and arranged to high level processes like a decision support process: One of the outstanding features of service-oriented architectures is the possibility to compose new services from existing ones, which can be done programmatically or via declaration (workflow or process design). This allows e. g. the definition of new warning processes which could be adapted easily to new requirements. • An access layer which may contain graphical user interfaces for decision support, monitoring- or visualization-systems: To for example visualize time series graphical user interfaces request sensor data simply via the SOS. 4.BENEFIT The integration platform is realized on top of well known and widely used open source software implementing industrial standards. New sensors could be added easily to the infrastructure. Client components don't need to be adjusted if new sensor-types or -individuals are added to the system, because they access the sensors via standardized services. With implementing SWE fully compatible to the OGC specification it is possible to establish the "detection" and integration of sensors via the Web. Thus realizing a system of systems that combines early warning system functionality at different levels of detail (distant early warning systems, monitoring systems and any sensor system) is feasible.

Understanding Montane Snow Water Equivalent Response to Climate Change and Variability

NASA Astrophysics Data System (ADS)

Huning, L. S.; AghaKouchak, A.

2017-12-01

Large populations worldwide rely on the seasonal snowpack for the majority of their water resources. Warming temperatures and other hydrometeorological changes impact the timing, distribution, and amount of montane snow water equivalent (SWE). Therefore, developing an improved understanding of the historical response to changing atmospheric drivers across snow-dominated mountainous regions has significant societal value related to water resources management and environmental hazards (i.e. flooding and droughts) for a future warming climate. Utilizing multi-decadal snow data sets and a probabilistic risk model over mountain ranges such as the Sierra Nevada (USA), the response of snowpack characteristics (e.g. SWE/snowfall, peak SWE, day of peak SWE, melt rate, etc.) to unit changes in hydrometeorological quantities (e.g. air temperature, humidity, winds, etc.) is quantified. The likelihood that the amount of SWE will exceed specified amounts (e.g. long-term peak SWE value) is presented for a range of climatic conditions. This study compares hydrologic response of montane SWE across windward and leeward basins, elevational bands, and regions of differing physiographic characteristics to understand how projected global warming such as a unit increase in air temperature or changes in other hydrometeorological quantities impact SWE at different spatial scales (i.e. basin-wide and range-wide). It provides insight that can be used to understand vulnerabilities of the seasonal snowpack to changes in climatic and atmospheric conditions.

Power Doppler Ultrasonography and Shear Wave Elastography as Complementary Imaging Methods for Suspected Local Breast Cancer Recurrence.

PubMed

Jales, Rodrigo Menezes; Dória, Maira Teixeira; Serra, Kátia Piton; Miranda, Mila Meneguelli; Menossi, Carlos Alberto; Schumacher, Klaus; Sarian, Luis Otávio

2018-06-01

To prospectively investigate the diagnostic accuracy and clinical consequences of power Doppler morphologic criteria and shear wave elastography (SWE) as complementary imaging methods for evaluation of suspected local breast cancer recurrence in the ipsilateral breast or chest wall. Thirty-two breast masses with a suspicion of local breast cancer recurrence on B-mode ultrasonography underwent complementary power Doppler and SWE evaluations. Power Doppler morphologic criteria were classified as avascular, hypovascular, or hypervascular. Shear wave elastography was classified according to a 5-point scale (SWE score) and SWE maximum elasticity. Diagnostic accuracy was assessed by the sensitivity, specificity, and area under the curve. A decision curve analysis assessed clinical consequences of each method. The reference standard for diagnosis was defined as core needle or excisional biopsy. Histopathologic examinations revealed 9 (28.2%) benign and 23 (71.8%) malignant cases. Power Doppler ultrasonography (US) had sensitivity of 34.8% (95% confidence interval [CI], 6.6%-62.9%) and specificity of 45.4% (95% CI, 19.3%-71.5%). The SWE score (≥3) had sensitivity of 87.0% (95% CI, 66.4%-97.2%) and specificity of 44.4% (95% CI, 13.7%-78.8%). The SWE maximum elasticity (velocity > 6.5cm/s) had sensitivity of 87% (95% CI, 66.4%-97.2%) and specificity of 77.8% (95% CI, 40.0% to 97.2%). The areas under the curves for the SWE score and SWE maximum elasticity were 0.71 (95% CI, 0.53-0.87) and 0.82 (95% CI, 0.64-0.93), respectively (P = .32). Power Doppler US is unsuitable for discrimination between local breast cancer recurrence and fibrosis. Although the SWE score and SWE maximum elasticity can make this discrimination, the use of these methods to determine biopsy may lead to poorer clinical outcomes than the current practice of performing biopsies of all suspicious masses. © 2017 by the American Institute of Ultrasound in Medicine.

A new qualitative pattern classification of shear wave elastograghy for solid breast mass evaluation.

PubMed

Cong, Rui; Li, Jing; Guo, Song

2017-02-01

To examine the efficacy of qualitative shear wave elastography (SWE) in the classification and evaluation of solid breast masses, and to compare this method with conventional ultrasonograghy (US), quantitative SWE parameters and qualitative SWE classification proposed before. From April 2015 to March 2016, 314 consecutive females with 325 breast masses who decided to undergo core needle biopsy and/or surgical biopsy were enrolled. Conventional US and SWE were previously performed in all enrolled subjects. Each mass was classified by two different qualitative classifications. One was established in our study, herein named the Qual1. Qual1 could classify the SWE images into five color patterns by the visual evaluations: Color pattern 1 (homogeneous pattern); Color pattern 2 (comparative homogeneous pattern); Color pattern 3 (irregularly heterogeneous pattern); Color pattern 4 (intralesional echo pattern); and Color pattern 5 (the stiff rim sign pattern). The second qualitative classification was named Qual2 here, and included a four-color overlay pattern classification (Tozaki and Fukuma, Acta Radiologica, 2011). The Breast Imaging Reporting and Data System (BI-RADS) assessment and quantitative SWE parameters were recorded. Diagnostic performances of conventional US, SWE parameters, and combinations of US and SWE parameters were compared. With pathological results as the gold standard, of the 325 examined breast masses, 139 (42.77%) samples were malignant and 186 (57.23%) were benign. The Qual1 showed a higher Az value than the Qual2 and quantitative SWE parameters (all P<0.05). When applying Qual1=Color pattern 1 for downgrading and Qual1=Color pattern 5 for upgrading the BI-RADS categories, we obtained the highest Az value (0.951), and achieved a significantly higher specificity (86.56%, P=0.002) than that of the US (81.18%) with the same sensitivity (94.96%). The qualitative classification proposed in this study may be representative of SWE parameters and has potential to be relevant assistance in breast mass diagnoses. Copyright © 2016. Published by Elsevier B.V.

End-of-winter snow depth variability on glaciers in Alaska

NASA Astrophysics Data System (ADS)

McGrath, Daniel; Sass, Louis; O'Neel, Shad; Arendt, Anthony; Wolken, Gabriel; Gusmeroli, Alessio; Kienholz, Christian; McNeil, Christopher

2015-08-01

A quantitative understanding of snow thickness and snow water equivalent (SWE) on glaciers is essential to a wide range of scientific and resource management topics. However, robust SWE estimates are observationally challenging, in part because SWE can vary abruptly over short distances in complex terrain due to interactions between topography and meteorological processes. In spring 2013, we measured snow accumulation on several glaciers around the Gulf of Alaska using both ground- and helicopter-based ground-penetrating radar surveys, complemented by extensive ground truth observations. We found that SWE can be highly variable (40% difference) over short spatial scales (tens to hundreds of meters), especially in the ablation zone where the underlying ice surfaces are typically rough. Elevation provides the dominant basin-scale influence on SWE, with gradients ranging from 115 to 400 mm/100 m. Regionally, total accumulation and the accumulation gradient are strongly controlled by a glacier's distance from the coastal moisture source. Multiple linear regressions, used to calculate distributed SWE fields, show that robust results require adequate sampling of the true distribution of multiple terrain parameters. Final SWE estimates (comparable to winter balances) show reasonable agreement with both the Parameter-elevation Relationships on Independent Slopes Model climate data set (9-36% difference) and the U.S. Geological Survey Alaska Benchmark Glaciers (6-36% difference). All the glaciers in our study exhibit substantial sensitivity to changing snow-rain fractions, regardless of their location in a coastal or continental climate. While process-based SWE projections remain elusive, the collection of ground-penetrating radar (GPR)-derived data sets provides a greatly enhanced perspective on the spatial distribution of SWE and will pave the way for future work that may eventually allow such projections.

Improving the Accuracy of the AFWA-NASA (ANSA) Blended Snow-Cover Product over the Lower Great Lakes Region

NASA Technical Reports Server (NTRS)

Hall, Dorothy K.; Foster, James L.; Kumar, Sujay; Chien, Janety Y. L.; Riggs, George A.

2012-01-01

The Air Force Weather Agency (AFWA) -- NASA blended snow-cover product, called ANSA, utilizes Earth Observing System standard snow products from the Moderate- Resolution Imaging Spectroradiometer (MODIS) and the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) to map daily snow cover and snow-water equivalent (SWE) globally. We have compared ANSA-derived SWE with SWE values calculated from snow depths reported at 1500 National Climatic Data Center (NCDC) co-op stations in the Lower Great Lakes Basin. Compared to station data, the ANSA significantly underestimates SWE in densely-forested areas. We use two methods to remove some of the bias observed in forested areas to reduce the root-mean-square error (RMSE) between the ANSA- and station-derived SWE. First, we calculated a 5- year mean ANSA-derived SWE for the winters of 2005-06 through 2009-10, and developed a five-year mean bias-corrected SWE map for each month. For most of the months studied during the five-year period, the 5-year bias correction improved the agreement between the ANSA-derived and station-derived SWE. However, anomalous months such as when there was very little snow on the ground compared to the 5-year mean, or months in which the snow was much greater than the 5-year mean, showed poorer results (as expected). We also used a 7-day running mean (7DRM) bias correction method using days just prior to the day in question to correct the ANSA data. This method was more effective in reducing the RMSE between the ANSA- and co-op-derived SWE values, and in capturing the effects of anomalous snow conditions.

Relating Satellite Gravimetry Data To Global Snow Water Equivalent Data

NASA Astrophysics Data System (ADS)

Baumann, Sabine

2017-04-01

In 04/2002, the gravimetric satellites GRACE were launched. They measure Earth's gravity via a precise microwave system. These satellites assess changes of Earth's mass. Main contributions of these changes originate from hydrological compartments as e.g. surface water, groundwater, soil moisture, or snow water equivalent (SWE). The benefit of GRACE data is to receive a direct measured signal. The data are not calibrated with other data (as e.g. done in models) or unusable due to particular Earth's surface conditions (e.g. AMSR-e for thick and wet snow surfaces). GRACE data show changes in total water storage (TWS) but cannot distinguish between different sources. Therefore, other data, models, and methods are necessary to extract the different compartments. Due to the spatial resolution of 200,000 km2 and an accuracy of 2.5 cm w.e., mostly other global products are compared with GRACE. In this study, the hydrological model WGHM (TWS and SWE), the land surface model GLDAS (TWS and SWE), and the passive microwave sensor AMSR-E (SWE) are compared with the GRACE data. All data have to be pre-processed in the same way as the GRACE data to be comparable. A correlation analysis was performed between the different products assuming that changes in TWS can be linked to changes in SWE if either SWE is the dominant compartment of TWS or if SWE changes proportionally with TWS. To focus on the SWE product a second correlation was performed only for the winter season. Spatial extent was focused on the large permafrost areas in North America and Russia. By this method, those areas were detected in which GRACE data can be integrated for SWE data assessment to, for example, improve the models.

Shear Wave Elastography--A New Quantitative Assessment of Post-Irradiation Neck Fibrosis.

PubMed

Liu, K H; Bhatia, K; Chu, W; He, L T; Leung, S F; Ahuja, A T

2015-08-01

Shear wave elastography (SWE) is a new technique which provides quantitative assessment of soft tissue stiffness. The aim of this study was to assess the reliability of SWE stiffness measurements and its usefulness in evaluating post-irradiation neck fibrosis. 50 subjects (25 patients with previous radiotherapy to the neck and 25 sex and age-matched controls) were recruited for comparison of SWE stiffness measurements (Aixplorer, Supersonic Imagine). 30 subjects (16 healthy individuals and 14 post-irradiated patients) were recruited for a reliability study of SWE stiffness measurements. SWE stiffness measurements of the sternocleidomastoid muscle and the overlying subcutaneous tissues of the neck were made. The cross-sectional area and thickness of the sternocleidomastoid muscle and the overlying subcutaneous tissue thickness of the neck were also measured. The post-irradiation duration of the patients was recorded. The intraclass correlation coefficients for the intraoperator and interoperator reliability of deep and subcutaneous tissue SWE stiffness ranged from 0.90-0.99 and 0.77-0.94, respectively. The SWE stiffness measurements (mean +/- SD) of deep and subcutaneous tissues were significantly higher in the post-irradiated patients (64.6 ± 46.8 kPa and 63.9 ± 53.1 kPa, respectively) than the sex and age-matched controls (19.9 ± 7.8 kPa and 15.3 ± 8.37 respectively) (p < 0.001). The SWE stiffness increased with increasing post-irradiation therapy duration in the Kruskal Wallis test (p < 0.001) and correlated with muscle atrophy and subcutaneous tissue thinning (p < 0.01). SWE is a reliable technique and may potentially be an objective and specific tool in quantifying deep and subcutaneous tissue stiffness, which in turn reflects the severity of neck fibrosis. © Georg Thieme Verlag KG Stuttgart · New York.

What are the characteristics of breast cancers misclassified as benign by quantitative ultrasound shear wave elastography?

PubMed

Vinnicombe, S J; Whelehan, P; Thomson, K; McLean, D; Purdie, C A; Jordan, L B; Hubbard, S; Evans, A J

2014-04-01

Shear wave elastography (SWE) is a promising adjunct to greyscale ultrasound in differentiating benign from malignant breast masses. The purpose of this study was to characterise breast cancers which are not stiff on quantitative SWE, to elucidate potential sources of error in clinical application of SWE to evaluation of breast masses. Three hundred and two consecutive patients examined by SWE who underwent immediate surgery for breast cancer were included. Characteristics of 280 lesions with suspicious SWE values (mean stiffness >50 kPa) were compared with 22 lesions with benign SWE values (<50 kPa). Statistical significance of the differences was assessed using non-parametric goodness-of-fit tests. Pure ductal carcinoma in situ (DCIS) masses were more often soft on SWE than masses representing invasive breast cancer. Invasive cancers that were soft were more frequently: histological grade 1, tubular subtype, ≤10 mm invasive size and detected at screening mammography. No significant differences were found with respect to the presence of invasive lobular cancer, vascular invasion, hormone and HER-2 receptor status. Lymph node positivity was less common in soft cancers. Malignant breast masses classified as benign by quantitative SWE tend to have better prognostic features than those correctly classified as malignant. • Over 90 % of cancers assessable with ultrasound have a mean stiffness >50 kPa. • 'Soft' invasive cancers are frequently small (≤10 mm), low grade and screen-detected. • Pure DCIS masses are more often soft than invasive cancers (>40 %). • Large symptomatic masses are better evaluated with SWE than small clinically occult lesions. • When assessing small lesions, 'softness' should not raise the threshold for biopsy.

Diagnostic value of commercially available shear-wave elastography for breast cancers: integration into BI-RADS classification with subcategories of category 4.

PubMed

Youk, Ji Hyun; Gweon, Hye Mi; Son, Eun Ju; Han, Kyung Hwa; Kim, Jeong-Ah

2013-10-01

To evaluate the diagnostic performance of shear-wave elastography (SWE) for breast cancer and to determine whether the integration of SWE into BI-RADS with subcategories of category 4 improves the diagnostic performance. A total of 389 breast masses (malignant 120, benign 269) in 324 women who underwent SWE before ultrasound-guided core biopsy or surgery were included. The qualitative SWE feature was assessed using a four-colour overlay pattern. Quantitative elasticity values including the lesion-to-fat elasticity ratio (Eratio) were measured. Diagnostic performance of B-mode ultrasound, SWE, or their combined studies was compared using the area under the ROC curve (AUC). AUC of Eratio (0.952) was the highest among elasticity values (mean, maximum, and minimum elasticity, 0.949, 0.939, and 0.928; P = 0.04) and AUC of colour pattern was 0.947. AUC of combined studies was significantly higher than for a single study (P < 0.0001). When adding SWE to category 4 lesions, lesions were dichotomised according to % of malignancy: 2.1 % vs. 43.2 % (category 4a) and 0 % vs. 100 % (category 4b) for Eratio and 2.4 % vs. 25.8 % (category 4a) for colour pattern (P < 0.05). Shear-wave elastography showed a good diagnostic performance. Adding SWE features to BI-RADS improved the diagnostic performance and may be helpful to stratify category 4 lesions. • Quantitative and qualitative shear-wave elastography provides further diagnostic information during breast ultrasound. • The elasticity ratio (E ratio ) showed the best diagnostic performance in SWE. • E ratio and four-colour overlay pattern significantly differed between benign and malignant lesions. • SWE features allowed further stratification of BI-RADS category 4 lesions.

A New Estimate of North American Mountain Snow Accumulation From Regional Climate Model Simulations

NASA Astrophysics Data System (ADS)

Wrzesien, Melissa L.; Durand, Michael T.; Pavelsky, Tamlin M.; Kapnick, Sarah B.; Zhang, Yu; Guo, Junyi; Shum, C. K.

2018-02-01

Despite the importance of mountain snowpack to understanding the water and energy cycles in North America's montane regions, no reliable mountain snow climatology exists for the entire continent. We present a new estimate of mountain snow water equivalent (SWE) for North America from regional climate model simulations. Climatological peak SWE in North America mountains is 1,006 km3, 2.94 times larger than previous estimates from reanalyses. By combining this mountain SWE value with the best available global product in nonmountain areas, we estimate peak North America SWE of 1,684 km3, 55% greater than previous estimates. In our simulations, the date of maximum SWE varies widely by mountain range, from early March to mid-April. Though mountains comprise 24% of the continent's land area, we estimate that they contain 60% of North American SWE. This new estimate is a suitable benchmark for continental- and global-scale water and energy budget studies.

Intra-observer reproducibility and diagnostic performance of breast shear-wave elastography in Asian women.

PubMed

Park, Hye Young; Han, Kyung Hwa; Yoon, Jung Hyun; Moon, Hee Jung; Kim, Min Jung; Kim, Eun-Kyung

2014-06-01

Our aim was to evaluate intra-observer reproducibility of shear-wave elastography (SWE) in Asian women. Sixty-four breast masses (24 malignant, 40 benign) were examined with SWE in 53 consecutive Asian women (mean age, 44.9 y old). Two SWE images were obtained for each of the lesions. The intra-observer reproducibility was assessed by intra-class correlation coefficients (ICC). We also evaluated various clinicoradiologic factors that can influence reproducibility in SWE. The ICC of intra-observer reproducibility was 0.789. In clinicoradiologic factor evaluation, masses surrounded by mixed fatty and glandular tissue (ICC: 0.619) showed lower intra-observer reproducibility compared with lesions that were surrounded by glandular tissue alone (ICC: 0.937; p < 0.05). Overall, the intra-observer reproducibility of breast SWE was excellent in Asian women. However, it may decrease when breast tissue is in a heterogeneous background. Therefore, SWE should be performed carefully in these cases. Copyright © 2014 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Seasonal prediction and predictability of Eurasian spring snow water equivalent in NCEP Climate Forecast System version 2 reforecasts

NASA Astrophysics Data System (ADS)

He, Qiong; Zuo, Zhiyan; Zhang, Renhe; Zhang, Ruonan

2018-01-01

The spring snow water equivalent (SWE) over Eurasia plays an important role in East Asian and Indian monsoon rainfall. This study evaluates the seasonal prediction capability of NCEP Climate Forecast System version 2 (CFSv2) retrospective forecasts (1983-2010) for the Eurasian spring SWE. The results demonstrate that CFSv2 is able to represent the climatological distribution of the observed Eurasian spring SWE with a lead time of 1-3 months, with the maximum SWE occurring over western Siberia and Northeastern Europe. For a longer lead time, the SWE is exaggerated in CFSv2 because the start of snow ablation in CFSv2 lags behind that of the observation, and the simulated snowmelt rate is less than that in the observation. Generally, CFSv2 can simulate the interannual variations of the Eurasian spring SWE 1-5 months ahead of time but with an exaggerated magnitude. Additionally, the downtrend in CFSv2 is also overestimated. Because the initial conditions (ICs) are related to the corresponding simulation results significantly, the robust interannual variability and the downtrend in the ICs are most likely the causes for these biases. Moreover, CFSv2 exhibits a high potential predictability for the Eurasian spring SWE, especially the spring SWE over Siberia, with a lead time of 1-5 months. For forecasts with lead times longer than 5 months, the model predictability gradually decreases mainly due to the rapid decrease in the model signal.

Cosmic-Ray Moisture Probe on North Slope of Alaska Field Campaign Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Desilets, Darin

2016-06-15

In September of 2014 a wide-area snow monitoring device was installed at the U.S. Department of Energy (DOE)’s Barrow, Alaska Atmospheric Radiation Measurement (ARM) Climate Research Facility site. The device is special in that it uses measurements of cosmic-ray neutrons as a proxy for snow water equivalent (SWE) depth. A unique characteristic of the technology is that it integrates over a wide area (as much as 40 ha), in contrast to conventional ground-based technologies, which essentially give point samples. Conventional point-scale technologies are problematic in the Arctic, both because extreme weather conditions are taxing on equipment, and because point measurementsmore » can fail to accurately characterize the average SWE over a larger area, even when excellent precision is obtained. The sensor installed in Barrow is, by far, the northernmost of a constellation of sites that makeup the U.S. COsmic ray Soil Moisture Observing System (COSMOS). The sensor is used for SWE measurements in winter and soil moisture measurements in summer. The ability of this type of sensor to operate in the Arctic had not been verified until now. The cosmic-ray sensor was installed on a tripod located approximately 150 m south of the ARM User Facility (Figure 1), and within boundaries of land managed by the ARM Facility. The sensor consists of both “bare” and “moderated” channels, where the moderated channel is the primary output used to calculate SWE. A QDL2100 data logger with pressure sensor was located inside of the User Facility, and a Campbell CS215 temperature and humidity sensor was attached to a rail on the upper deck of the User Facility, to enable near-real-time absolute humidity corrections to the data. The cosmic-ray sensors are connected to the data logger using an armored Cat5e cable that lies on top of the tundra. Data are retrieved hourly via Iridium satellite link.« less

Children’s Marking of Verbal –s by Nonmainstream English Dialect and Clinical Status

PubMed Central

Cleveland, Lesli H.; Oetting, Janna B.

2015-01-01

Purpose Children’s marking of verbal –s was examined by their dialect (African American English [AAE] vs. Southern White English [SWE]) and clinical status (specific language impairment [SLI] vs. typically developing [TD]) and as a function of 4 linguistic variables (verb regularity, negation, expression of a habitual activity, and expression of historical present tense). Method The data were language samples from 57 six-year-olds who varied by their dialect and clinical status (AAE: SLI = 14, TD = 12; SWE: SLI = 12, TD = 19). Results The AAE groups produced lower rates of marking than did the SWE groups, and the SWE SLI group produced lower rates of marking than did the SWE TD group. Although low numbers of verb contexts made it difficult to evaluate the linguistic variables, there was evidence of their influence, especially for verb regularity and negation. The direction and magnitude of the effects were often (but not always) consistent with what has been described in the adult dialect literature. Conclusion Verbal –s can be used to help distinguish children with and without SLI in SWE but not in AAE. Clinicians can apply these findings to other varieties of AAE and SWE and other dialects by considering rates of marking and the effects of linguistic variables on marking. PMID:23813205

A role for the Swe1 checkpoint kinase during filamentous growth of Saccharomyces cerevisiae.

PubMed Central

La Valle, R; Wittenberg, C

2001-01-01

In this study we show that inactivation of Hsl1 or Hsl7, negative regulators of the Swe1 kinase, enhances the invasive behavior of haploid and diploid cells. The enhancement of filamentous growth caused by inactivation of both genes is mediated via the Swe1 protein kinase. Whereas Swe1 contributes noticeably to the effectiveness of haploid invasive growth under all conditions tested, its contribution to pseudohyphal growth is limited to the morphological response under standard assay conditions. However, Swe1 is essential for pseudohyphal differentiation under a number of nonstandard assay conditions including altered temperature and increased nitrogen. Swe1 is also required for pseudohyphal growth in the absence of Tec1 and for the induction of filamentation by butanol, a related phenomenon. Although inactivation of Hsl1 is sufficient to suppress the defect in filamentous growth caused by inactivation of Tec1 or Flo8, it is insufficient to promote filamentous growth in the absence of both factors. Moreover, inactivation of Hsl1 will not bypass the requirement for nitrogen starvation or growth on solid medium for pseudohyphal differentiation. We conclude that the Swe1 kinase modulates filamentous development under a broad spectrum of conditions and that its role is partially redundant with the Tec1 and Flo8 transcription factors. PMID:11404321

The performance of the new enhanced-resolution satellite passive microwave dataset applied for snow water equivalent estimation

NASA Astrophysics Data System (ADS)

Pan, J.; Durand, M. T.; Jiang, L.; Liu, D.

2017-12-01

The newly-processed NASA MEaSures Calibrated Enhanced-Resolution Brightness Temperature (CETB) reconstructed using antenna measurement response function (MRF) is considered to have significantly improved fine-resolution measurements with better georegistration for time-series observations and equivalent field of view (FOV) for frequencies with the same monomial spatial resolution. We are looking forward to its potential for the global snow observing purposes, and therefore aim to test its performance for characterizing snow properties, especially the snow water equivalent (SWE) in large areas. In this research, two candidate SWE algorithms will be tested in China for the years between 2005 to 2010 using the reprocessed TB from the Advanced Microwave Scanning Radiometer for EOS (AMSR-E), with the results to be evaluated using the daily snow depth measurements at over 700 national synoptic stations. One of the algorithms is the SWE retrieval algorithm used for the FengYun (FY) - 3 Microwave Radiation Imager. This algorithm uses the multi-channel TB to calculate SWE for three major snow regions in China, with the coefficients adapted for different land cover types. The second algorithm is the newly-established Bayesian Algorithm for SWE Estimation with Passive Microwave measurements (BASE-PM). This algorithm uses the physically-based snow radiative transfer model to find the histogram of most-likely snow property that matches the multi-frequency TB from 10.65 to 90 GHz. It provides a rough estimation of snow depth and grain size at the same time and showed a 30 mm SWE RMS error using the ground radiometer measurements at Sodankyla. This study will be the first attempt to test it spatially for satellite. The use of this algorithm benefits from the high resolution and the spatial consistency between frequencies embedded in the new dataset. This research will answer three questions. First, to what extent can CETB increase the heterogeneity in the mapped SWE? Second, will the SWE estimation error statistics be improved using this high-resolution dataset? Third, how will the SWE retrieval accuracy be improved using CETB and the new SWE retrieval techniques?

Diagnostic potential of real-time elastography (RTE) and shear wave elastography (SWE) to differentiate benign and malignant thyroid nodules: A systematic review and meta-analysis.

PubMed

Hu, Xiangdong; Liu, Yujiang; Qian, Linxue

2017-10-01

Real-time elastography (RTE) and shear wave elastography (SWE) are noninvasive and easily available imaging techniques that measure the tissue strain, and it has been reported that the sensitivity and the specificity of elastography were better in differentiating between benign and malignant thyroid nodules than conventional technologies. Relevant articles were searched in multiple databases; the comparison of elasticity index (EI) was conducted with the Review Manager 5.0. Forest plots of the sensitivity and specificity and SROC curve of RTE and SWE were performed with STATA 10.0 software. In addition, sensitivity analysis and bias analysis of the studies were conducted to examine the quality of articles; and to estimate possible publication bias, funnel plot was used and the Egger test was conducted. Finally 22 articles which eventually satisfied the inclusion criteria were included in this study. After eliminating the inefficient, benign and malignant nodules were 2106 and 613, respectively. The meta-analysis suggested that the difference of EI between benign and malignant nodules was statistically significant (SMD = 2.11, 95% CI [1.67, 2.55], P < .00001). The overall sensitivities of RTE and SWE were roughly comparable, whereas the difference of specificities between these 2 methods was statistically significant. In addition, statistically significant difference of AUC between RTE and SWE was observed between RTE and SWE (P < .01). The specificity of RTE was statistically higher than that of SWE; which suggests that compared with SWE, RTE may be more accurate on differentiating benign and malignant thyroid nodules.

Diagnostic potential of real-time elastography (RTE) and shear wave elastography (SWE) to differentiate benign and malignant thyroid nodules

PubMed Central

Hu, Xiangdong; Liu, Yujiang; Qian, Linxue

2017-01-01

Abstract Background: Real-time elastography (RTE) and shear wave elastography (SWE) are noninvasive and easily available imaging techniques that measure the tissue strain, and it has been reported that the sensitivity and the specificity of elastography were better in differentiating between benign and malignant thyroid nodules than conventional technologies. Methods: Relevant articles were searched in multiple databases; the comparison of elasticity index (EI) was conducted with the Review Manager 5.0. Forest plots of the sensitivity and specificity and SROC curve of RTE and SWE were performed with STATA 10.0 software. In addition, sensitivity analysis and bias analysis of the studies were conducted to examine the quality of articles; and to estimate possible publication bias, funnel plot was used and the Egger test was conducted. Results: Finally 22 articles which eventually satisfied the inclusion criteria were included in this study. After eliminating the inefficient, benign and malignant nodules were 2106 and 613, respectively. The meta-analysis suggested that the difference of EI between benign and malignant nodules was statistically significant (SMD = 2.11, 95% CI [1.67, 2.55], P < .00001). The overall sensitivities of RTE and SWE were roughly comparable, whereas the difference of specificities between these 2 methods was statistically significant. In addition, statistically significant difference of AUC between RTE and SWE was observed between RTE and SWE (P < .01). Conclusion: The specificity of RTE was statistically higher than that of SWE; which suggests that compared with SWE, RTE may be more accurate on differentiating benign and malignant thyroid nodules. PMID:29068996

Shear Wave Elastographic Alterations in the Kidney After Extracorporeal Shock Wave Lithotripsy.

PubMed

Turkay, Rustu; Inci, Ercan; Bas, Derya; Atar, Arda

2018-03-01

Extracorporeal shock wave lithotripsy (ESWL) is a method used frequently for the treatment of renal stone disease. Although its safety is proven, there are still concerns about its unwanted effects on kidneys. In this prospective study, we aimed to evaluate renal tissue alterations with shear wave elastography (SWE) after ESWL. We also studied the correlation between SWE and resistive index (RI) changes. The study included 59 patients who underwent ESWL treatment for renal stone disease. We performed SWE and color Doppler ultrasonography to calculate SWE and RI values before, 1 hour after, and 1 week after lithotripsy treatment. A binary comparison was performed by the Bonferroni test. The correlation between SWE and RI values was evaluated by a Pearson correlation analysis. The patients included 26 women (44.1%) and 33 men (55.9%). Their ages ranged from 20 to 65 years (mean ± SD, 45.0 ± 1.1 years). Stone diameters ranged from 7 to 19 mm (mean, 13.0 ± 0.5 mm). There was a significant difference in SWE values before and 1 hour after lithotripsy treatment (P = .001; P < .01). In the follow-up measurement 1 week after treatment, this difference disappeared (P > .99; P > .05). Resistive index values increased significantly 1 hour after lithotripsy treatment and returned to prelithotripsy values 1 week after treatment. In the correlation analysis, SWE and RI values were not correlated. Measurements of alterations in SWE values after ESWL can provide useful information about renal tissue injury. © 2017 by the American Institute of Ultrasound in Medicine.

BOREAS HYD-2 Estimated Snow Water Equivalent (SWE) from Microwave Measurements

NASA Technical Reports Server (NTRS)

Powell, Hugh; Chang, Alfred T. C.; Hall, Forrest G. (Editor); Knapp, David E. (Editor); Smith, David E. (Technical Monitor)

2000-01-01

The surface meteorological data collected at the Boreal Ecosystem-Atmosphere Study (BOREAS) tower and ancillary sites are being used as inputs to an energy balance model to monitor the amount of snow storage in the boreal forest region. The BOREAS Hydrology (HYD)-2 team used Snow Water Equivalent (SWE) derived from an energy balance model and in situ observed SWE to compare the SWE inferred from airborne and spaceborne microwave data, and to assess the accuracy of microwave retrieval algorithms. The major external measurements that are needed are snowpack temperature profiles, in situ snow areal extent, and SWE data. The data in this data set were collected during February 1994 and cover portions of the Southern Study Area (SSA), Northern Study Area (NSA), and the transect areas. The data are available from BORIS as comma-delimited tabular ASCII files. The SWE data are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). The data files are available on a CD-ROM (see document number 20010000884).

Assessment of Liver Fibrosis Using Real-time Shear-wave Elastography for Patients with Hepatitis B e Antigen-negative Chronic Hepatitis B and Alanine Transaminase <2 Times the Upper Limit of Normal.

PubMed

Liu, Jing-Hua; Zou, Yu; Chang, Wei; Wu, Jun; Zou, Yu; Xie, Yu-Chen; Lu, Yong-Ping; Wei, Jia

2017-01-01

We assessed liver fibrosis using real-time shear-wave elastography (SWE) combined with liver biopsy (LB) for patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB) and alanine transaminase < 2 times the upper limit of normal and hepatitis B virus DNA < 2000 IU/ml. A total of 107 patients met the inclusion criteria. Real- ime SWE and ultrasoundassisted liver biopsies were consecutively performed. Fibrosis was staged according to the METAVIR scoring system. Analyses of receiver operating characteristic curve were performed to calculate the optimal area under the receiver operating characteristic curve for F0-F1 versus F2-F4, F0-F2 versus F3-F4, and F0-F3 versus F4 for real-time SWE. The most concurrent liver fibrosis degrees were between F1 and F2 for these HBeAg-negative CHB patients. Liver stiffness increased in parallel with the degree of liver fibrosis using SWE measurements. The area under the receiver operating characteristic curves was 0.881 (95% confidence interval [CI]: 0.704-1.000) for SWE (p = 0.004); 0.912 (95% CI: 0.836-0.987) for SWE (p = 0.000); 0.981 (95% CI: 0.956-1.000) for SWE (p = 0.000); 0.974 (95% CI: 0.936-1.000) for SWE (p = 0.000) when comparing F0 versus F1-F4, F0-F1 versus F2-F4, F0-F2 versus F3-F4, and F0-F3 versus F4, respectively. SWE has the advantage of providing an image of liver stiffness in real-time. As an alternative to LB, the development of all these noninvasive methods for dynamic evaluation of liver fibrosis will decrease the need for LB, making clinical care safer and more convenient for patients with liver diseases.

Effect of dietary seaweed extracts and fish oil supplementation in sows on performance, intestinal microflora, intestinal morphology, volatile fatty acid concentrations and immune status of weaned pigs.

PubMed

Leonard, S G; Sweeney, T; Bahar, B; Lynch, B P; O'Doherty, J V

2011-02-01

A 2x2 factorial experiment (ten sows per treatment) was conducted to investigate the effect of maternal dietary supplementation with a seaweed extract (SWE; 0 v. 10·0 g/d) and fish oil (FO; 0 v. 100 g/d) inclusion from day 109 of gestation until weaning (day 26) on pig performance post-weaning (PW) and intestinal morphology, selected microflora and immune status of pigs 9 d PW. The SWE contained laminarin (10 %), fucoidan (8 %) and ash (82 %) and the FO contained 40 % EPA and 25 % DHA. Pigs weaned from SWE-supplemented sows had higher daily gain (P=0·063) between days 0 and 21 PW and pigs weaned from FO-supplemented sows had higher daily gain (P<0·05) and gain to feed ratio (P<0·01) between days 7 and 14 PW. There was an interaction between maternal SWE and FO supplementation on caecal Escherichia coli numbers (P<0·05) and the villous height to crypt depth ratio in the ileum (P<0·01) and jejunum (P<0·05) in pigs 9 d PW. Pigs weaned from SWE-supplemented sows had lower caecal E. coli and a higher villous height to crypt depth ratio in the ileum and jejunum compared with non-SWE-supplemented sows (P<0·05). There was no effect of SWE on E. coli numbers and villous height to crypt depth ratio with FO inclusion. Maternal FO supplementation induced an increase in colonic mRNA abundance of IL-1α and IL-6 (P<0·05), while SWE supplementation induced an increase in ileal TNF-α (P<0·01) and colonic TFF3 mRNA expression (P<0·05). In conclusion, these results demonstrate that SWE and FO supplementation to the maternal diet influenced the gastrointestinal environment and performance of the weaned pig.

Estimation de l'equivalent en eau de la neige en milieu subarctique du Quebec par teledetection micro-ondes passives

NASA Astrophysics Data System (ADS)

Vachon, Francois

The snow cover (extent, depth and water equivalent) is an important factor in assessing the water balance of a territory. In a context of deregulation of electricity, better knowledge of the quantity of water resulting from snowmelt that will be available for hydroelectric power generation has become a major challenge for the managers of Hydro-Quebec's generating plant. In fact, the snow on the ground represents nearly one third of Hydro-Quebec's annual energy reserve and the proportion is even higher for northern watersheds. Snowcover knowledge would therefore help optimize the management of energy stocks. The issue is especially important when one considers that better management of water resources can lead to substantial economic benefits. The Research Institute of Hydro-Quebec (IREQ), our research partner, is currently attempting to optimize the streamfiow forecasts made by its hydrological models by improving the quality of the inputs. These include a parameter known as the snow water equivalent (SWE) which characterizes the properties of the snow cover. At the present time, SWE data is obtained from in situ measurements, which are both sporadic and scattered, and does not allow the temporal and spatial variability of SWE to be characterized adequately for the needs of hydrological models. This research project proposes to provide the Quebec utility's hydrological models with distributed SWE information about its northern watersheds. The targeted accuracy is 15% for the proposed period of analysis covering the winter months of January, February and March of 2001 to 2006. The methodology is based on the HUT snow emission model and uses the passive microwave remote sensing data acquired by the SSM/I sensor. Monitoring of the temporal and spatial variations in SWE is done by inversion of the model and benefits from the assimilation of in situ data to characterize the state of snow cover during the season. Experimental results show that the assimilation technique of in situ data (density and depth) can reproduce the temporal variations in SWE with a RMSE error of 15.9% (R2=0.76). The analysis of land cover within the SSMI pixels can reduce this error to 14.6% ( R2=0.66) for SWE values below 300 mm. Moreover, the results show that the fluctuations of SWE values are driven by changes in snow depths. Indeed, the use of a constant value for the density of snow is feasible and makes it possible to get as good if not better results. These results will allow IREQ to assess the suitability of using snow cover information provided by the remote sensing data in its forecasting models. This improvement in SWE characterization will meet the needs of IREQ for its work on optimization of the quality of hydrological simulations. The originality and relevance of this work are based primarily on the type of method used to quantify SWE and the site where it is applied. The proposed method focuses on the inversion of the HUT model from passive remote sensing data and assimilates in situ data. Moreover, this approach allows high SWE values (> 300 mm) to be quantified, which was impossible with previous methods. These high SWE values are encountered in areas with large amounts of snow such as northern Quebec. Keywords. remote sensing, microwave, snow water equivalent (SWE), model, retrieval, data assimilation, SWE monitoring, spatialization Complete reference. Vachon, F. (2009) Snow water equivalent retrieval in a subartic environment of Quebec using passive microwave remote sensing. Ph.D. Thesis, Sherbrooke University, Sherbrooke, 211 p.

Numerical simulation of flood inundation using a well-balanced kinetic scheme for the shallow water equations with bulk recharge and discharge

NASA Astrophysics Data System (ADS)

Ersoy, Mehmet; Lakkis, Omar; Townsend, Philip

2016-04-01

The flow of water in rivers and oceans can, under general assumptions, be efficiently modelled using Saint-Venant's shallow water system of equations (SWE). SWE is a hyperbolic system of conservation laws (HSCL) which can be derived from a starting point of incompressible Navier-Stokes. A common difficulty in the numerical simulation of HSCLs is the conservation of physical entropy. Work by Audusse, Bristeau, Perthame (2000) and Perthame, Simeoni (2001), proposed numerical SWE solvers known as kinetic schemes (KSs), which can be shown to have desirable entropy-consistent properties, and are thus called well-balanced schemes. A KS is derived from kinetic equations that can be integrated into the SWE. In flood risk assessment models the SWE must be coupled with other equations describing interacting meteorological and hydrogeological phenomena such as rain and groundwater flows. The SWE must therefore be appropriately modified to accommodate source and sink terms, so kinetic schemes are no longer valid. While modifications of SWE in this direction have been recently proposed, e.g., Delestre (2010), we depart from the extant literature by proposing a novel model that is "entropy-consistent" and naturally extends the SWE by respecting its kinetic formulation connections. This allows us to derive a system of partial differential equations modelling flow of a one-dimensional river with both a precipitation term and a groundwater flow model to account for potential infiltration and recharge. We exhibit numerical simulations of the corresponding kinetic schemes. These simulations can be applied to both real world flood prediction and the tackling of wider issues on how climate and societal change are affecting flood risk.

Snowpack Estimates Improve Water Resources Climate-Change Adaptation Strategies

NASA Astrophysics Data System (ADS)

Lestak, L.; Molotch, N. P.; Guan, B.; Granger, S. L.; Nemeth, S.; Rizzardo, D.; Gehrke, F.; Franz, K. J.; Karsten, L. R.; Margulis, S. A.; Case, K.; Anderson, M.; Painter, T. H.; Dozier, J.

2010-12-01

Observed climate trends over the past 50 years indicate a reduction in snowpack water storage across the Western U.S. As the primary water source for the region, the loss in snowpack water storage presents significant challenges for managing water deliveries to meet agricultural, municipal, and hydropower demands. Improved snowpack information via remote sensing shows promise for improving seasonal water supply forecasts and for informing decadal scale infrastructure planning. An ongoing project in the California Sierra Nevada and examples from the Rocky Mountains indicate the tractability of estimating snowpack water storage on daily time steps using a distributed snowpack reconstruction model. Fractional snow covered area (FSCA) derived from Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data were used with modeled snowmelt from the snowpack model to estimate snow water equivalent (SWE) in the Sierra Nevada (64,515 km2). Spatially distributed daily SWE estimates were calculated for 10 years, 2000-2009, with detailed analysis for two anamolous years, 2006, a wet year and 2009, an over-forecasted year. Sierra-wide mean SWE was 0.8 cm for 01 April 2006 versus 0.4 cm for 01 April 2009, comparing favorably with known outflow. Modeled SWE was compared to in-situ (observed) SWE for 01 April 2006 for the Feather (northern Sierra, lower-elevation) and Merced (central Sierra, higher-elevation) basins, with mean modeled SWE 80% of observed SWE. Integration of spatial SWE estimates into forecasting operations will allow for better visualization and analysis of high-altitude late-season snow missed by in-situ snow sensors and inter-annual anomalies associated with extreme precipitation events/atmospheric rivers. Collaborations with state and local entities establish protocols on how to meet current and future information needs and improve climate-change adaptation strategies.

Utility of Shear Wave Elastography for Differentiating Biliary Atresia From Infantile Hepatitis Syndrome.

PubMed

Wang, Xiaoman; Qian, Linxue; Jia, Liqun; Bellah, Richard; Wang, Ning; Xin, Yue; Liu, Qinglin

2016-07-01

The purpose of this study was to investigate the potential utility of shear wave elastography (SWE) for diagnosis of biliary atresia and for differentiating biliary atresia from infantile hepatitis syndrome by measuring liver stiffness. Thirty-eight patients with biliary atresia and 17 patients with infantile hepatitis syndrome were included, along with 31 healthy control infants. The 3 groups underwent SWE. The hepatic tissue of each patient with biliary atresia had been surgically biopsied. Statistical analyses for mean values of the 3 groups were performed. Optimum cutoff values using SWE for differentiation between the biliary atresia and control groups were calculated by a receiver operating characteristic (ROC) analysis. The mean SWE values ± SD for the 3 groups were as follows: biliary atresia group, 20.46 ± 10.19 kPa; infantile hepatitis syndrome group, 6.29 ± 0.99 kPa; and control group, 6.41 ± 1.08 kPa. The mean SWE value for the biliary atresia group was higher than the values for the control and infantile hepatitis syndrome groups (P < .01). The mean SWE values between the control and infantile hepatitis syndrome groups were not statistically different. The ROC analysis showed a cutoff value of 8.68 kPa for differentiation between the biliary atresia and control groups. The area under the ROC curve was 0.997, with sensitivity of 97.4%, specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 96.9%. Correlation analysis suggested a positive correlation between SWE values and age for patients with biliary atresia, with a Pearson correlation coefficient of 0.463 (P < .05). The significant increase in liver SWE values in neonates and infants with biliary atresia supports their application for differentiating biliary atresia from infantile hepatitis syndrome.

Point-shear wave elastography predicts liver hypertrophy after portal vein embolization and postoperative liver failure.

PubMed

Hocquelet, A; Frulio, N; Gallo, G; Laurent, C; Papadopoulos, P; Salut, C; Denys, A; Trillaud, H

2018-06-01

To correlate point-shear wave elastography (SWE) with liver hypertrophy after right portal vein embolization (RPVE) and to determine its usefulness in predicting postoperative liver failure in patients undergoing partial liver resection. Point-SWE was performed the day before RPVE in 56 patients (41 men) with a median age of 66 years. The percentage (%) of future remnant liver (FRL) volume increase was defined as: %FRL post -%FRL pre %FRL pre ×100 and assessed on computed tomography performed 4 weeks after RPVE. Median (range) %FRL pre and %FRL post was respectively, 31.5% (12-48%) and 41% (23-61%) (P<0.001), with a median %FRL volume increase of 25.6% (-8; 123%). SWE correlated with %FRL volume increase (P=-0.510; P<0.001). SWV (P=0.003) and %FRL pre (P<0.001) were associated with %FRL volume increase at multivariate regression analysis. Forty-three patients (77%) were operated. Postoperative liver failure occurred in 14 patients (32.5%). Median SWE was different between the group with (1.68m/s) and without liver failure (1.07m/s) (P=0.018). The AUROC of SWE predicting liver failure was 0.724 with a best cut-off of 1.31m/s, corresponding to a sensitivity of 21%, specificity of 96%, positive predictive value 75% and negative predictive value of 72%. SWE was the single independent preoperative variable associated with liver failure. SWE assessed by point-SWE is a simple and useful tool to predict the FRL volume increase and postoperative liver failure in a population of patients with liver tumor. Copyright © 2018 Société française de radiologie. Published by Elsevier Masson SAS. All rights reserved.

Bias of shear wave elasticity measurements in thin layer samples and a simple correction strategy.

PubMed

Mo, Jianqiang; Xu, Hao; Qiang, Bo; Giambini, Hugo; Kinnick, Randall; An, Kai-Nan; Chen, Shigao; Luo, Zongping

2016-01-01

Shear wave elastography (SWE) is an emerging technique for measuring biological tissue stiffness. However, the application of SWE in thin layer tissues is limited by bias due to the influence of geometry on measured shear wave speed. In this study, we investigated the bias of Young's modulus measured by SWE in thin layer gelatin-agar phantoms, and compared the result with finite element method and Lamb wave model simulation. The result indicated that the Young's modulus measured by SWE decreased continuously when the sample thickness decreased, and this effect was more significant for smaller thickness. We proposed a new empirical formula which can conveniently correct the bias without the need of using complicated mathematical modeling. In summary, we confirmed the nonlinear relation between thickness and Young's modulus measured by SWE in thin layer samples, and offered a simple and practical correction strategy which is convenient for clinicians to use.

Effect of Arctic Amplification on Design Snow Loads in Alaska

DTIC Science & Technology

2016-09-01

snow water equivalent UFC Unified Facilities Criteria UTC Coordinated Universal Time Keywords: Alaska, Arctic amplification, climate change...extreme value analysis, snow loads, snow water equivalent , SWE Acknowledgements: This work was conducted with support from the Strategic... equivalent (SWE) of the snowpack. We acquired SWE data from a number of sources that provide automatic or manual observations, reanalysis data, or

Shear-wave elastography in breast ultrasonography: the state of the art

PubMed Central

2017-01-01

Shear-wave elastography (SWE) is a recently developed ultrasound technique that can visualize and measure tissue elasticity. In breast ultrasonography, SWE has been shown to be useful for differentiating benign breast lesions from malignant breast lesions, and it has been suggested that SWE enhances the diagnostic performance of ultrasonography, potentially improving the specificity of conventional ultrasonography using the Breast Imaging Reporting and Data System criteria. More recently, not only has SWE been proven useful for the diagnosis of breast cancer, but has also been shown to provide valuable information that can be used as a preoperative predictor of the prognosis or response to chemotherapy. PMID:28513127

Simulation of Seasonal Snow Microwave TB Using Coupled Multi-Layered Snow Evolution and Microwave Emission Models

NASA Technical Reports Server (NTRS)

Brucker, Ludovic; Royer, Alain; Picard, Ghislain; Langlois, Alex; Fily, Michel

2014-01-01

The accurate quantification of SWE has important societal benefits, including improving domestic and agricultural water planning, flood forecasting and electric power generation. However, passive-microwave SWE algorithms suffer from variations in TB due to snow metamorphism, difficult to distinguish from those due to SWE variations. Coupled snow evolution-emission models are able to predict snow metamorphism, allowing us to account for emissivity changes. They can also be used to identify weaknesses in the snow evolution model. Moreover, thoroughly evaluating coupled models is a contribution toward the assimilation of TB, which leads to a significant increase in the accuracy of SWE estimates.

Estimation of Snow Parameters Based on Passive Microwave Remote Sensing and Meteorological Information

NASA Technical Reports Server (NTRS)

Tsang, Leung; Hwang, Jenq-Neng

1996-01-01

A method to incorporate passive microwave remote sensing measurements within a spatially distributed snow hydrology model to provide estimates of the spatial distribution of Snow Water Equivalent (SWE) as a function of time is implemented. The passive microwave remote sensing measurements are at 25 km resolution. However, in mountain regions the spatial variability of SWE over a 25 km footprint is large due to topographic influences. On the other hand, the snow hydrology model has built-in topographic information and the capability to estimate SWE at a 1 km resolution. In our work, the snow hydrology SWE estimates are updated and corrected using SSM/I passive microwave remote sensing measurements. The method is applied to the Upper Rio Grande River Basin in the mountains of Colorado. The change in prediction of SWE from hydrology modeling with and without updating is compared with measurements from two SNOTEL sites in and near the basin. The results indicate that the method incorporating the remote sensing measurements into the hydrology model is able to more closely estimate the temporal evolution of the measured values of SWE as a function of time.

Combining Passive Microwave and Optical Data to Estimate Snow Water Equivalent in Afghanistan's Hindu Kush

NASA Astrophysics Data System (ADS)

Dozier, J.; Bair, N.; Calfa, A. A.; Skalka, C.; Tolle, K.; Bongard, J.

2015-12-01

The task is to estimate spatiotemporally distributed estimates of snow water equivalent (SWE) in snow-dominated mountain environments, including those that lack on-the-ground measurements such as the Hindu Kush range in Afghanistan. During the snow season, we can use two measurements: (1) passive microwave estimates of SWE, which generally underestimate in the mountains; (2) fractional snow-covered area from MODIS. Once the snow has melted, we can reconstruct the accumulated SWE back to the last significant snowfall by calculating the energy used in melt. The reconstructed SWE values provide a training set for predictions from the passive microwave SWE and snow-covered area. We examine several machine learning methods—regression-boosted decision trees, bagged trees, neural networks, and genetic programming—to estimate SWE. All methods work reasonably well, with R2 values greater than 0.8. Predictors built with multiple years of data reduce the bias that usually appears if we predict one year from just one other year's training set. Genetic programming tends to produce results that additionally provide physical insight. Adding precipitation estimates from the Global Precipitation Measurements mission is in progress.

Measuring personal recovery - psychometric properties of the Swedish Questionnaire about the Process of Recovery (QPR-Swe).

PubMed

Argentzell, Elisabeth; Hultqvist, Jenny; Neil, Sandra; Eklund, Mona

2017-10-01

Personal recovery, defined as an individual process towards meaning, is an important target within mental health services. Measuring recovery hence requires reliable and valid measures. The Process of Recovery Questionnaire (QPR) was developed for that purpose. The aim was to develop a Swedish version of the QPR (QPR-Swe) and explore its psychometric properties in terms of factor structure, internal consistency, construct validity and sensitivity to change. A total of 226 participants entered the study. The factor structure was investigated by Principal Component Analysis and Scree plot. Construct validity was addressed in terms of convergent validity against indicators of self-mastery, self-esteem, quality of life and self-rated health. A one-factor solution of QPR-Swe received better support than a two-factor solution. Good internal consistency was indicated, α = 0.92, and construct validity was satisfactory. The QPR-Swe showed preliminary sensitivity to change. The QPR-Swe showed promising initial psychometric properties in terms of internal consistency, convergent validity and sensitivity to change. The QPR-Swe is recommended for use in research and clinical contexts to assess personal recovery among people with mental illness.

Feasibility Assessment of Shear Wave Elastography to Rotator Cuff Muscle

PubMed Central

Itoigawa, Yoshiaki; Sperling, John W.; Steinmann, Scott P.; Chen, Qingshan; Song, Pengfei; Chen, Shigao; Itoi, Eiji; Hatta, Taku; An, Kai-Nan

2017-01-01

Introduction Pre -surgical measurement of supraspinatus muscle extensibility would be important for rotator cuff repair. The purpose of the present study was to explore the potential feasibility of a shear wave ultrasound electrograph (SWE) based method, combined with B-mode ultrasound, to non-invasively measure in vivo stiffness of supraspinatus muscle, and thus obtaining the key information on supraspinatus muscle extensibility. Materials and Methods Our investigation consisted of 2 steps. First, we evaluated orientation of the supraspinatus muscle fiber on cadaveric shoulders without rotator cuff tear in order to optimize the ultrasound probe positions for SWE imaging. Second, we investigated the feasibility of quantifying the normal supraspinatus muscle stiffness by SWE in vivo. Results The supraspinatus muscle was divided into four anatomical regions, namely anterior superficial (AS), posterior superficial (PS), anterior deep (AD) and posterior deep (PD) regions. SWE was evaluated at each of these regions. SWE stiffness on AD, AS, PD, and PS were measured as 40.0±12.4, 34.0±9.9, 32.7±12.7, 39.1±15.7 kPa, respectively. Conclusions SWE combined with B-Mode ultrasound image may be a feasible method to quantify local tissue stiffness of the rotator cuff muscles. PMID:25557287

Accuracy of real-time shear wave elastography for assessing liver fibrosis in chronic hepatitis C: a pilot study.

PubMed

Ferraioli, Giovanna; Tinelli, Carmine; Dal Bello, Barbara; Zicchetti, Mabel; Filice, Gaetano; Filice, Carlo

2012-12-01

Real-time shear wave elastography (SWE) is a novel, noninvasive method to assess liver fibrosis by measuring liver stiffness. This single-center study was conducted to assess the accuracy of SWE in patients with chronic hepatitis C (CHC), in comparison with transient elastography (TE), by using liver biopsy (LB) as the reference standard. Consecutive patients with CHC scheduled for LB by referring physicians were studied. One hundred and twenty-one patients met inclusion criteria. On the same day, real-time SWE using the ultrasound (US) system, Aixplorer (SuperSonic Imagine S.A., Aix-en-Provence, France), TE using FibroScan (Echosens, Paris, France), and US-assisted LB were consecutively performed. Fibrosis was staged according to the METAVIR scoring system. Analyses of receiver operating characteristic (ROC) curve were performed to calculate optimal area under the ROC curve (AUROC) for F0-F1 versus F2-F4, F0- F2 versus F3-F4, and F0-F3 versus F4 for both real-time SWE and TE. Liver stiffness values increased in parallel with degree of liver fibrosis, both with SWE and TE. AUROCs were 0.92 (95% confidence interval [CI]: 0.85-0.96) for SWE and 0.84 (95% CI: 0.76-0.90) for TE (P = 0.002), 0.98 (95% CI: 0.94-1.00) for SWE and 0.96 (95% CI: 0.90-0.99) for TE (P = 0.14), and 0.98 (95% CI: 0.93-1.00) for SWE and 0.96 (95% CI: 0.91-0.99) for TE (P = 0.48), when comparing F0-F1 versus F2- F4, F0- F2 versus F3-F4, and F0 -F3 versus F4, respectively. The results of this study show that real-time SWE is more accurate than TE in assessing significant fibrosis (≥ F2). With respect to TE, SWE has the advantage of imaging liver stiffness in real time while guided by a B-mode image. Thus, the region of measurement can be guided with both anatomical and tissue stiffness information. Copyright © 2012 American Association for the Study of Liver Diseases.

Research of marine sensor web based on SOA and EDA

NASA Astrophysics Data System (ADS)

Jiang, Yongguo; Dou, Jinfeng; Guo, Zhongwen; Hu, Keyong

2015-04-01

A great deal of ocean sensor observation data exists, for a wide range of marine disciplines, derived from in situ and remote observing platforms, in real-time, near-real-time and delayed mode. Ocean monitoring is routinely completed using sensors and instruments. Standardization is the key requirement for exchanging information about ocean sensors and sensor data and for comparing and combining information from different sensor networks. One or more sensors are often physically integrated into a single ocean `instrument' device, which often brings in many challenges related to diverse sensor data formats, parameters units, different spatiotemporal resolution, application domains, data quality and sensors protocols. To face these challenges requires the standardization efforts aiming at facilitating the so-called Sensor Web, which making it easy to provide public access to sensor data and metadata information. In this paper, a Marine Sensor Web, based on SOA and EDA and integrating the MBARI's PUCK protocol, IEEE 1451 and OGC SWE 2.0, is illustrated with a five-layer architecture. The Web Service layer and Event Process layer are illustrated in detail with an actual example. The demo study has demonstrated that a standard-based system can be built to access sensors and marine instruments distributed globally using common Web browsers for monitoring the environment and oceanic conditions besides marine sensor data on the Web, this framework of Marine Sensor Web can also play an important role in many other domains' information integration.

Estimating snow water equivalent (SWE) using interferometric synthetic aperture radar (InSAR)

NASA Astrophysics Data System (ADS)

Deeb, Elias J.

Since the early 1990s, radar interferometry and interferometric synthetic aperture radar (InSAR) have been used extensively to measure changes in the Earth's surface. Previous research has presented theory for estimating snow properties, including potential for snow water equivalent (SWE) retrieval, using InSAR. The motivation behind using remote sensing to estimate SWE is to provide a more complete, continuous set of "observations" to assist in water management operations, climate change studies, and flood hazard forecasting. The research presented here primarily investigates the feasibility of using the InSAR technique at two different wavelengths (C-Band and L-Band) for SWE retrieval of dry snow within the Kuparuk watershed, North Slope, Alaska. Estimating snow distribution around meteorological towers on the coastal plain using a three-day repeat orbit of C-Band InSAR data was successful (Chapter 2). A longer wavelength L-band SAR is evaluated for SWE retrievals (Chapter 3) showing the ability to resolve larger snow accumulation events over a longer period of time. Comparisons of InSAR estimates and late spring manual sampling of SWE show a R2 = 0.61 when a coherence threshold is used to eliminate noisy SAR data. Qualitative comparisons with a high resolution digital elevation model (DEM) highlight areas of scour on windward slopes and areas of deposition on leeward slopes. When compared to a mid-winter transect of manually sampled snow depths, the InSAR SWE estimates yield a RMSE of 2.21cm when a bulk snow density is used and corrections for bracketing the satellite acquisition timing is performed. In an effort to validate the interaction of radar waves with a snowpack, the importance of the "dry snow" assumption for the estimation of SWE using InSAR is tested with an experiment in Little Cottonwood Canyon, Alta, Utah (Chapter 5). Snow wetness is shown to have a significant effect on the velocity of propagation within the snowpack. Despite the radar interaction with the snowpack being complex, the methodology for using InSAR to estimate SWE shows great promise when considering NASA's proposed L-Band, weekly repeat time interval, interferometric DESDynI (Deformation, Ecosystem Structure, and Dynamics of Ice) mission.

Clinical application of shear wave elastography (SWE) in the diagnosis of benign and malignant breast diseases.

PubMed

Chang, Jung Min; Moon, Woo Kyung; Cho, Nariya; Yi, Ann; Koo, Hye Ryoung; Han, Wonsik; Noh, Dong-Young; Moon, Hyeong-Gon; Kim, Seung Ja

2011-08-01

Shear wave elastography (SWE) is an emerging technique which can obtain quantitative elasticity values in breast disease. We therefore evaluated the diagnostic performance of SWE for the differentiation of breast masses compared with conventional ultrasound (US). Conventional US and SWE were performed by three experienced radiologists for 158 consecutive women who had been scheduled for US-guided core biopsy or surgical excision in 182 breast masses (89 malignancies and 93 benign; mean size, 1.76 cm). For each lesion, quantitative elasticity was measured in terms of the Young's modulus (in kilopascals, kPa) with SWE, and BI-RADS final categories were assessed with conventional US. The mean elasticity values were significantly higher in malignant masses (153.3 kPa ± 58.1) than in benign masses (46.1 kPa ± 42.9), (P < 0.0001). The average mean elasticity values of invasive ductal (157.5 ± 57.07) or invasive lobular (169.5 ± 61.06) carcinomas were higher than those of ductal carcinoma in situ (117.8 kPa ± 54.72). The average mean value was 49.58 ± 43.51 for fibroadenoma, 35.3 ± 31.2 for fibrocystic changes, 69.5 ± 63.2 for intraductal papilloma, and 149.5 ± 132.4 for adenosis or stromal fibrosis. The optimal cut-off value, yielding the maximal sum of sensitivity and specificity, was 80.17 kPa, and the sensitivity and specificity of SWE were 88.8% (79 of 89) and 84.9% (79 of 93). The area under the ROC curve (Az value) was 0.898 for conventional US, 0.932 for SWE, and 0.982 for combined data. In conclusion, there were significant differences in the elasticity values of benign and malignant masses as well as invasive and intraductal cancers with SWE. Our results suggest that SWE has the potential to aid in the differentiation of benign and malignant breast lesions.

Evaluating a Local Ensemble Transform Kalman Filter snow cover data assimilation method to estimate SWE within a high-resolution hydrologic modeling framework across Western US mountainous regions

NASA Astrophysics Data System (ADS)

Oaida, C. M.; Andreadis, K.; Reager, J. T., II; Famiglietti, J. S.; Levoe, S.

2017-12-01

Accurately estimating how much snow water equivalent (SWE) is stored in mountainous regions characterized by complex terrain and snowmelt-driven hydrologic cycles is not only greatly desirable, but also a big challenge. Mountain snowpack exhibits high spatial variability across a broad range of spatial and temporal scales due to a multitude of physical and climatic factors, making it difficult to observe or estimate in its entirety. Combing remotely sensed data and high resolution hydrologic modeling through data assimilation (DA) has the potential to provide a spatially and temporally continuous SWE dataset at horizontal scales that capture sub-grid snow spatial variability and are also relevant to stakeholders such as water resource managers. Here, we present the evaluation of a new snow DA approach that uses a Local Ensemble Transform Kalman Filter (LETKF) in tandem with the Variable Infiltration Capacity macro-scale hydrologic model across the Western United States, at a daily temporal resolution, and a horizontal resolution of 1.75 km x 1.75 km. The LETKF is chosen for its relative simplicity, ease of implementation, and computational efficiency and scalability. The modeling/DA system assimilates daily MODIS Snow Covered Area and Grain Size (MODSCAG) fractional snow cover over, and has been developed to efficiently calculate SWE estimates over extended periods of time and covering large regional-scale areas at relatively high spatial resolution, ultimately producing a snow reanalysis-type dataset. Here we focus on the assessment of SWE produced by the DA scheme over several basins in California's Sierra Nevada Mountain range where Airborne Snow Observatory data is available, during the last five water years (2013-2017), which include both one of the driest and one of the wettest years. Comparison against such a spatially distributed SWE observational product provides a greater understanding of the model's ability to estimate SWE and SWE spatial variability, and highlights under which conditions snow cover DA can add value in estimating SWE.

Sensor metadata blueprints and computer-aided editing for disciplined SensorML

NASA Astrophysics Data System (ADS)

Tagliolato, Paolo; Oggioni, Alessandro; Fugazza, Cristiano; Pepe, Monica; Carrara, Paola

2016-04-01

The need for continuous, accurate, and comprehensive environmental knowledge has led to an increase in sensor observation systems and networks. The Sensor Web Enablement (SWE) initiative has been promoted by the Open Geospatial Consortium (OGC) to foster interoperability among sensor systems. The provision of metadata according to the prescribed SensorML schema is a key component for achieving this and nevertheless availability of correct and exhaustive metadata cannot be taken for granted. On the one hand, it is awkward for users to provide sensor metadata because of the lack in user-oriented, dedicated tools. On the other, the specification of invariant information for a given sensor category or model (e.g., observed properties and units of measurement, manufacturer information, etc.), can be labor- and timeconsuming. Moreover, the provision of these details is error prone and subjective, i.e., may differ greatly across distinct descriptions for the same system. We provide a user-friendly, template-driven metadata authoring tool composed of a backend web service and an HTML5/javascript client. This results in a form-based user interface that conceals the high complexity of the underlying format. This tool also allows for plugging in external data sources providing authoritative definitions for the aforementioned invariant information. Leveraging these functionalities, we compiled a set of SensorML profiles, that is, sensor metadata blueprints allowing end users to focus only on the metadata items that are related to their specific deployment. The natural extension of this scenario is the involvement of end users and sensor manufacturers in the crowd-sourced evolution of this collection of prototypes. We describe the components and workflow of our framework for computer-aided management of sensor metadata.

Enhancing the Value of Sensor-based Observations by Capturing the Knowledge of How An Observation Came to Be

NASA Astrophysics Data System (ADS)

Fredericks, J.; Rueda-Velasquez, C. A.

2016-12-01

As we move from keeping data on our disks to sharing it with the world, often in real-time, we are obligated to also tell an unknown user about how our observations were made. Data that are shared must not only have ownership metadata, unit descriptions and content formatting information. The provider must also share information that is needed to assess the data as it relates to potential re-use. A user must be able to assess the limitations and capabilities of the sensor, as it is configured, to understand its value. For example, when an instrument is configured, it typically affects the data accuracy and operational limits of the sensor. An operator may sacrifice data accuracy to achieve a broader operational range and visa versa. If you are looking at newly discovered data, it is important to be able to find all of the information that relates to assessing the data quality for your particular application. Traditionally, metadata are captured by data managers who usually do not know how the data are collected. By the time data are distributed, this knowledge is often gone, buried within notebooks or hidden in documents that are not machine-harvestable and often not human-readable. In a recently funded NSF EarthCube Integrative Activity called X-DOMES (Cross-Domain Observational Metadata in EnviroSensing), mechanisms are underway to enable the capture of sensor and deployment metadata by sensor manufacturers and field operators. The support has enabled the development of a community ontology repository (COR) within the Earth Science Information Partnership (ESIP) community, fostering easy creation of resolvable terms for the broader community. This tool enables non-experts to easily develop W3C standards-based content, promoting the implementation of Semantic Web technologies for enhanced discovery of content and interoperability in workflows. The X-DOMES project is also developing a SensorML Viewer/Editor to provide an easy interface for sensor manufacturers and field operators to fully-describe sensor capabilities and configuration/deployment content - automatically generating it in machine-harvestable encodings that can be referenced by data managers and/or associated with the data through web-services, such as the OGC SWE Sensor Observation Service.

Static and dynamic superheated water extraction of essential oil components from Thymus vulgaris L.

PubMed

Dawidowicz, Andrzej L; Rado, Ewelina; Wianowska, Dorota

2009-09-01

Superheated water extraction (SWE) performed in both static and dynamic condition (S-SWE and D-SWE, respectively) was applied for the extraction of essential oil from Thymus vulgaris L. The influence of extraction pressure, temperature, time, and flow rate on the total yield of essential oil and the influence of extraction temperature on the extraction of some chosen components are discussed in the paper. The SWE extracts are related to PLE extracts with n-hexane and essential oil obtained by steam distillation. The superheated water extraction in dynamic condition seems to be a feasible option for the extraction of essential oil components from T. vulgaris L.

Estimating the snow water equivalent on a glacierized high elevation site (Forni Glacier, Italy)

NASA Astrophysics Data System (ADS)

Senese, Antonella; Maugeri, Maurizio; Meraldi, Eraldo; Verza, Gian Pietro; Azzoni, Roberto Sergio; Compostella, Chiara; Diolaiuti, Guglielmina

2018-04-01

We present and compare 11 years of snow data (snow depth and snow water equivalent, SWE) measured by an automatic weather station (AWS) and corroborated by data from field campaigns on the Forni Glacier in Italy. The aim of the analysis is to estimate the SWE of new snowfall and the annual SWE peak based on the average density of the new snow at the site (corresponding to the snowfall during the standard observation period of 24 h) and automated snow depth measurements. The results indicate that the daily SR50 sonic ranger measurements and the available snow pit data can be used to estimate the mean new snow density value at the site, with an error of ±6 kg m-3. Once the new snow density is known, the sonic ranger makes it possible to derive SWE values with an RMSE of 45 mm water equivalent (if compared with snow pillow measurements), which turns out to be about 8 % of the total SWE yearly average. Therefore, the methodology we present is interesting for remote locations such as glaciers or high alpine regions, as it makes it possible to estimate the total SWE using a relatively inexpensive, low-power, low-maintenance, and reliable instrument such as the sonic ranger.

Quantitative and noninvasive assessment of chronic liver diseases using two-dimensional shear wave elastography

PubMed Central

Xie, Li-Ting; Yan, Chun-Hong; Zhao, Qi-Yu; He, Meng-Na; Jiang, Tian-An

2018-01-01

Two-dimensional shear wave elastography (2D-SWE) is a rapid, simple and novel noninvasive method that has been proposed for assessing hepatic fibrosis in patients with chronic liver diseases (CLDs) based on measurements of liver stiffness. 2D-SWE can be performed easily at the bedside or in an outpatient clinic and yields immediate results with good reproducibility. Furthermore, 2D-SWE was an efficient method for evaluating liver fibrosis in small to moderately sized clinical trials. However, the quality criteria for the staging of liver fibrosis are not yet well defined. Liver fibrosis is the main pathological basis of liver stiffness and a key step in the progression from CLD to cirrhosis; thus, the management of CLD largely depends on the extent and progression of liver fibrosis. 2D-SWE appears to be an excellent tool for the early detection of cirrhosis and may have prognostic value in this context. Because 2D-SWE has high patient acceptance, it could be useful for monitoring fibrosis progression and regression in individual cases. However, multicenter data are needed to support its use. This study reviews the current status and future perspectives of 2D-SWE for assessments of liver fibrosis and discusses the technical advantages and limitations that impact its effective and rational clinical use. PMID:29531460

Attribution of spring snow water equivalent (SWE) changes over the northern hemisphere to anthropogenic effects

NASA Astrophysics Data System (ADS)

Jeong, Dae Il; Sushama, Laxmi; Naveed Khaliq, M.

2017-06-01

Snow is an important component of the cryosphere and it has a direct and important influence on water storage and supply in snowmelt-dominated regions. This study evaluates the temporal evolution of snow water equivalent (SWE) for the February-April spring period using the GlobSnow observation dataset for the 1980-2012 period. The analysis is performed for different regions of hemispherical to sub-continental scales for the Northern Hemisphere. The detection-attribution analysis is then performed to demonstrate anthropogenic and natural effects on spring SWE changes for different regions, by comparing observations with six CMIP5 model simulations for three different external forcings: all major anthropogenic and natural (ALL) forcings, greenhouse gas (GHG) forcing only, and natural forcing only. The observed spring SWE generally displays a decreasing trend, due to increasing spring temperatures. However, it exhibits a remarkable increasing trend for the southern parts of East Eurasia. The six CMIP5 models with ALL forcings reproduce well the observed spring SWE decreases at the hemispherical scale and continental scales, whereas important differences are noted for smaller regions such as southern and northern parts of East Eurasia and northern part of North America. The effects of ALL and GHG forcings are clearly detected for the spring SWE decline at the hemispherical scale, based on multi-model ensemble signals. The effects of ALL and GHG forcings, however, are less clear for the smaller regions or with single-model signals, indicating the large uncertainty in regional SWE changes, possibly due to stronger influence of natural climate variability.

Evaluation of SNODAS snow depth and snow water equivalent estimates for the Colorado Rocky Mountains, USA

USGS Publications Warehouse

Clow, David W.; Nanus, Leora; Verdin, Kristine L.; Schmidt, Jeffrey

2012-01-01

The National Weather Service's Snow Data Assimilation (SNODAS) program provides daily, gridded estimates of snow depth, snow water equivalent (SWE), and related snow parameters at a 1-km2 resolution for the conterminous USA. In this study, SNODAS snow depth and SWE estimates were compared with independent, ground-based snow survey data in the Colorado Rocky Mountains to assess SNODAS accuracy at the 1-km2 scale. Accuracy also was evaluated at the basin scale by comparing SNODAS model output to snowmelt runoff in 31 headwater basins with US Geological Survey stream gauges. Results from the snow surveys indicated that SNODAS performed well in forested areas, explaining 72% of the variance in snow depths and 77% of the variance in SWE. However, SNODAS showed poor agreement with measurements in alpine areas, explaining 16% of the variance in snow depth and 30% of the variance in SWE. At the basin scale, snowmelt runoff was moderately correlated (R2 = 0.52) with SNODAS model estimates. A simple method for adjusting SNODAS SWE estimates in alpine areas was developed that uses relations between prevailing wind direction, terrain, and vegetation to account for wind redistribution of snow in alpine terrain. The adjustments substantially improved agreement between measurements and SNODAS estimates, with the R2 of measured SWE values against SNODAS SWE estimates increasing from 0.42 to 0.63 and the root mean square error decreasing from 12 to 6 cm. Results from this study indicate that SNODAS can provide reliable data for input to moderate-scale to large-scale hydrologic models, which are essential for creating accurate runoff forecasts. Refinement of SNODAS SWE estimates for alpine areas to account for wind redistribution of snow could further improve model performance. Published 2011. This article is a US Government work and is in the public domain in the USA.

Monitoring of snowpack dynamics in mountainous terrain by cosmic-ray neutron sensing compared to Terrestrial Laser Scanning observations

NASA Astrophysics Data System (ADS)

Schattan, P.; Baroni, G.; Schrön, M.; Köhli, M.; Oswald, S. E.; Huttenlau, M.; Achleitner, S.

2017-12-01

Monitoring a mountain snowpack in a representative domain of several hectares is challenging due to its high heterogeneity in time and space. Recent studies have suggested cosmic-ray neutron sensing (CRNS) as a promising method for monitoring snow representatively at these scales. Little is known however about the depth of sensitivity, the effects of fractional snow coverage in complex terrain or the influence of snow density profiles. Therefore, a field campaign in the Austrian Alps was conducted from March 2014 to June 2016. The main scope was to evaluate the characteristics of CRNS for monitoring a snowpack in a relatively wet and mountainous environment. During the experiment, the study site experienced a peak snow accumulation in terms of snow water equivalent (SWE) of up to 600 mm in the 2014/2015 winter season. Snow depth (SD) and SWE measurements from an automatic weather station were compared to CRNS neutron counts. Several spatially distributed Terrestrial Laser Scanning (TLS)-based SD and SWE maps were additionally used to cope with the spatial heterogeneity of the site. Furthermore, an URANOS neutron transport model was set up to provide additional insights into the response of CRNS to the presence of a complex snowpack. Therein, spatially distributed SWE scenarios and different snow density assumptions are used for hypothesis testing. The field measurements revealed an unexpectedly high potential of CRNS for monitoring heterogeneous snowpack dynamics beyond shallow snowpacks. A clear, nonlinear relation was found for both SD and SWE with neutron counts. In contrast to previous studies suggesting signal saturation at around 100 mm of SWE, complete signal saturation was observed only for SWE values beyond 500 to 600 mm. In addition, first modelling results highlight the effects of snow density profiles, small-scale changes in SWE, and the complex patterns of fractional snow cover on neutron counts. Understanding the interactions between neutrons and snow cover in complex terrain potentially improves the transferability of the results to other locations.

Did Climate Change Cause the 2012-2014 California Drought?

NASA Astrophysics Data System (ADS)

Mao, Y.; Clark, E.; Xiao, M.; Nijssen, B.; Lettenmaier, D. P.

2014-12-01

California has experienced severe drought over the last three years, with especially deficient winter precipitation and mountain snowpack in 2013-2014. While the severity of California's water crisis this year is not in question, the causes of the drought are less clear, and there has been debate as to whether human-induced climate change is at least in part a cause of anomalously low winter precipitation (P) and snow water equivalent (SWE) this year, or whether the conditions are simply the result of natural variability that has been manifested in previous severe droughts in California. To provide more scientific insight to this question, we reconstructed, using the Variable Infiltration Capacity (VIC) hydrologic model, SWE and runoff from 1920 to 2014 at a spatial resolution of 1/16 degree over the Sierra Nevada range of California. We forced the VIC model with a temporally consistent set of index precipitation and temperature stations that are also used in the University of Washington's Drought Monitoring System for the West Coast Region (http://www.hydro.washington.edu/forecast/monitor_cali/index.shtml). We carried out trend analysis and examined cumulative probability for accumulated winter precipitation, SWE on Apr 1, annual, spring and winter runoff, average winter temperature (T) and SWE/P fraction. We also did correlation analysis between SWE and P as well as SWE and T. In addition, we used detrended temperature data to force the VIC model in order to analyze the role of climate change in SWE and runoff. Our results show that while the decreasing trend in SWE and earlier runoff peak in the year are related to long-term warming climate, there is no significant trend in winter P and there are lots of variability in the record of all variables. While this year's anomalously warm weather might have exacerbated the ongoing 3-year drought (and winter 2013-14 in particular), we conclude that natural variability is the main cause.

Shear Wave Elastography (SWE) for Monitoring of Treatment of Tendinopathies: A Double-blinded, Longitudinal Clinical Study.

PubMed

Dirrichs, Timm; Quack, Valentin; Gatz, Matthias; Tingart, Markus; Rath, Björn; Betsch, Marcel; Kuhl, Christiane K; Schrading, Simone

2018-03-01

We aimed to investigate the diagnostic accuracy with which shear wave elastography (SWE) can be used to monitor response to treatment of tendinopathies, and to compare it to conventional ultrasound (US)-imaging methods (B-mode US (B-US) and power Doppler US (PD-US)). A prospective Institutional Review Board-approved longitudinal study on 35 patients with 47 symptomatic tendons (17 Achilles-, 15 patellar-, and 15 humeral-epicondylar) who underwent standardized multimodal US and standardized clinical assessment before and after 6 months of treatment (tailored stretching exercise, sport break, and local Polidocanol) was carried out. All US studies were performed by radiologists blinded to the clinical symptoms on both tendon sides to avoid biased interpretations, by B-US, PD-US, and SWE, conducted in the same order, using a high-resolution linear 15 MHz probe (Aixplorer). Orthopedic surgeons who were in turn blinded to US imaging results used established orthopedic scores (Victorian Institute of Sports Assessment questionnaire for Achilles, Victorian Institute of Sports Assessment questionnaire for patellar tendons, and Disability Arm Shoulder Hand scoring system) to rate presence, degree, and possible resolution of symptoms. We analyzed the diagnostic accuracy with which the different US imaging methods were able to detect symptomatic tendons at baseline as well as treatment effects, with orthopedic scores serving as reference standard. B-US, PD-US, and SWE detected symptomatic tendons with a sensitivity of 66% (31 of 47), 72% (34 of 47), and 87.5% (41 of 47), respectively. Positive predictive value was 0.67 for B-US, 0.87 for PD-US, and 1 for SWE. After treatment, clinical scores improved in 68% (32 of 47) of tendons. Treatment effects were observable by B-US, PD-US, and SWE with a sensitivity of 3.1% (1 of 32), 28.1% (9 of 32), and 81.3% (26 of 32), respectively. B-US was false-positive in 68.8% (20 of 32), PD-US in 46.9% (15 of 32), and SWE in 12.5% (4 of 32) (SWE). Clinical scores and B-US, PD-US, and SWE findings correlated poorly (r = 0.24), moderately (r = 0.59), and strongly (r = 0.80). Unlike B-US or PD-US, SWE is able to depict processes associated with tendon healing and may be a useful tool to monitor treatment effects. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Influence of snowpack and melt energy heterogeneity on snow cover depletion and snowmelt runoff simulation in a cold mountain environment

NASA Astrophysics Data System (ADS)

DeBeer, Chris M.; Pomeroy, John W.

2017-10-01

The spatial heterogeneity of mountain snow cover and ablation is important in controlling patterns of snow cover depletion (SCD), meltwater production, and runoff, yet is not well-represented in most large-scale hydrological models and land surface schemes. Analyses were conducted in this study to examine the influence of various representations of snow cover and melt energy heterogeneity on both simulated SCD and stream discharge from a small alpine basin in the Canadian Rocky Mountains. Simulations were performed using the Cold Regions Hydrological Model (CRHM), where point-scale snowmelt computations were made using a snowpack energy balance formulation and applied to spatial frequency distributions of snow water equivalent (SWE) on individual slope-, aspect-, and landcover-based hydrological response units (HRUs) in the basin. Hydrological routines were added to represent the vertical and lateral transfers of water through the basin and channel system. From previous studies it is understood that the heterogeneity of late winter SWE is a primary control on patterns of SCD. The analyses here showed that spatial variation in applied melt energy, mainly due to differences in net radiation, has an important influence on SCD at multiple scales and basin discharge, and cannot be neglected without serious error in the prediction of these variables. A single basin SWE distribution using the basin-wide mean SWE (SWE ‾) and coefficient of variation (CV; standard deviation/mean) was found to represent the fine-scale spatial heterogeneity of SWE sufficiently well. Simulations that accounted for differences in (SWE ‾) among HRUs but neglected the sub-HRU heterogeneity of SWE were found to yield similar discharge results as simulations that included this heterogeneity, while SCD was poorly represented, even at the basin level. Finally, applying point-scale snowmelt computations based on a single SWE depth for each HRU (thereby neglecting spatial differences in internal snowpack energetics over the distributions) was found to yield similar SCD and discharge results as simulations that resolved internal energy differences. Spatial/internal snowpack melt energy effects are more pronounced at times earlier in spring before the main period of snowmelt and SCD, as shown in previously published work. The paper discusses the importance of these findings as they apply to the warranted complexity of snowmelt process simulation in cold mountain environments, and shows how the end-of-winter SWE distribution represents an effective means of resolving snow cover heterogeneity at multiple scales for modelling, even in steep and complex terrain.

A flexible geospatial sensor observation service for diverse sensor data based on Web service

NASA Astrophysics Data System (ADS)

Chen, Nengcheng; Di, Liping; Yu, Genong; Min, Min

Achieving a flexible and efficient geospatial Sensor Observation Service (SOS) is difficult, given the diversity of sensor networks, the heterogeneity of sensor data storage, and the differing requirements of users. This paper describes development of a service-oriented multi-purpose SOS framework. The goal is to create a single method of access to the data by integrating the sensor observation service with other Open Geospatial Consortium (OGC) services — Catalogue Service for the Web (CSW), Transactional Web Feature Service (WFS-T) and Transactional Web Coverage Service (WCS-T). The framework includes an extensible sensor data adapter, an OGC-compliant geospatial SOS, a geospatial catalogue service, a WFS-T, and a WCS-T for the SOS, and a geospatial sensor client. The extensible sensor data adapter finds, stores, and manages sensor data from live sensors, sensor models, and simulation systems. Abstract factory design patterns are used during design and implementation. A sensor observation service compatible with the SWE is designed, following the OGC "core" and "transaction" specifications. It is implemented using Java servlet technology. It can be easily deployed in any Java servlet container and automatically exposed for discovery using Web Service Description Language (WSDL). Interaction sequences between a Sensor Web data consumer and an SOS, between a producer and an SOS, and between an SOS and a CSW are described in detail. The framework has been successfully demonstrated in application scenarios for EO-1 observations, weather observations, and water height gauge observations.

European Multidisciplinary seafloor and the Observatory of the water column for Development; The setup of an interoperable Generic Sensor Module

NASA Astrophysics Data System (ADS)

Danobeitia, J.; Oscar, G.; Bartolomé, R.; Sorribas, J.; Del Rio, J.; Cadena, J.; Toma, D. M.; Bghiel, I.; Martinez, E.; Bardaji, R.; Piera, J.; Favali, P.; Beranzoli, L.; Rolin, J. F.; Moreau, B.; Andriani, P.; Lykousis, V.; Hernandez Brito, J.; Ruhl, H.; Gillooly, M.; Terrinha, P.; Radulescu, V.; O'Neill, N.; Best, M.; Marinaro, G.

2016-12-01

European Multidisciplinary seafloor and the Observatory of the water column for Development (EMSODEV) is a Horizon-2020 UE project whose overall objective is the operationalization of eleven marine observatories and four test sites distributed throughout Europe, from the Arctic to the Atlantic, from the Mediterranean to the Black Sea. The whole infrastructure is managed by the European consortium EMSO-ERIC (European Research Infrastructure Consortium) with the participation of 8 European countries and other partner countries. Now, we are implementing a Generic Sensor Module (EGIM) within the EMSO ERIC distributed marine research infrastructure. Our involvement is mainly on developing standard-compliant generic software for Sensor Web Enablement (SWE) on EGIM device. The main goal of this development is to support the sensors data acquisition on a new interoperable EGIM system. The EGIM software structure is made up of one acquisition layer located between the recorded data at EGIM module and the data management services. Therefore, two main interfaces are implemented: first, assuring the EGIM hardware acquisition and second allowing push and pull data from data management layer (Sensor Web Enable standard compliant). All software components used are Open source licensed and has been configured to manage different roles on the whole system (52º North SOS Server, Zabbix Monitoring System). The acquisition data module has been implemented with the aim to join all components for EGIM data acquisition and server fulfilling SOS standards interface. The system is already achieved awaiting for the first laboratory bench test and shallow water test connection to the OBSEA node, offshore Vilanova I la Geltrú (Barcelona, Spain). The EGIM module will record a wide range of ocean parameters in a long-term consistent, accurate and comparable manner from disciplines such as biology, geology, chemistry, physics, engineering, and computer science, from polar to subtropical environments, through the water column down to the deep sea. The measurements recorded along EMSO NODES are critical to respond accurately to the social and scientific challenges such as climate change, changes in marine ecosystems, and marine hazards.

Three-dimensional vs. two-dimensional shear-wave elastography of the testes - preliminary study on a healthy collective.

PubMed

Marcon, J; Trottmann, M; Rübenthaler, J; D'Anastasi, M; Stief, C G; Reiser, M F; Clevert, D A

2016-01-01

Shear wave elastography (SWE) and its derivative Supersonic Shear Imaging (SSI) are newer techniques for the determination of tissue elasticity by measuring the velocity of generated shear waves (SWV), which correlates positively with tissue stiffness.The techniques are integrated into many modern ultrasound systems and have been examined in the evaluation of viscoelastic properties of different organ systems. Two-dimensional shear wave elastography (2D SWE) of the testes has been found to be a useful tool in recent studies which included the determination of standard values in healthy volunteers. Three-dimensional shear wave elastography (3D SWE) is the latest development in elastography and is made possible by generation of a multiplanar three-dimensional map via volumetric acquisition with a special ultrasound transducer. This technique allows the assessment of tissue elasticity in a three-dimensional, fully accessible organ map.The aim of this preliminary study was to both evaluate the feasibility of 3D SWE and to compare 2D and 3D SWE standard values in the testes of healthy subjects. We examined the testes of healthy male volunteers (n = 32) with a mean age of 51.06±17.75 years (range 25-77 years) by B-mode ultrasound, 2D and 3D SWE techniques in September of 2016. Volunteers with a history of testicular pathologies were excluded. For all imaging procedures the SL15-4 linear transducer (bandwidth 4-15 MHz) as well as the SLV16-4 volumetric probe (bandwidth 4-16 MHz) of the Aixplorer® ultrasound device (SuperSonic Imagine, Aix-en-Provence, France) were used. Seven regions of interest (ROI, Q-Box®) within the testes were evaluated for SWV using both procedures. SWV values were described in m/s. Results were statistically evaluated using univariateanalysis. Mean SWV values were 1.05 m/s for the 2D SWE and 1.12 m/s for the 3D SWE.Comparisons of local areas delivered no statistically significant differences (p = 0.11 to p = 0.66), except for the region in the central portion in the superior part of the coronal plane (p = 0.03). Testicular volume was significanty higher by a mean of 1.72 ml when measured with 3D SWE (p = 0.001). 3D SWE proved to be a feasible diagnostic tool in the assessment of testicular tissue, providing the examiner with a fully accessible three-dimensional map in a multiplanar or multislice view. With this technique a more precise testicular imaging - especially if combined with the display of tissue stiffness in SWE - is available and therefore could improve the diagnostic work-up of scrotal masses or the routine investigation of infertile men. Further studies for a better understanding in the context of various testicular pathologies will be required.

Snow water equivalent monitoring retrieved by assimilating passive microwave observations in a coupled snowpack evolution and microwave emission models over North-Eastern Canada

NASA Astrophysics Data System (ADS)

Royer, A.; Larue, F.; De Sève, D.; Roy, A.; Vionnet, V.; Picard, G.; Cosme, E.

2017-12-01

Over northern snow-dominated basins, the snow water equivalent (SWE) is of primary interest for spring streamflow forecasting. SWE retrievals from satellite data are still not well resolved, in particular from microwave (MW) measurements, the only type of data sensible to snow mass. Also, the use of snowpack models is challenging due to the large uncertainties in meteorological input forcings. This project aims to improve SWE prediction by assimilation of satellite brightness temperature (TB), without any ground-based observations. The proposed approach is the coupling of a detailed multilayer snowpack model (Crocus) with a MW snow emission model (DMRT-ML). The assimilation scheme is a Sequential Importance Resampling Particle filter, through ensembles of perturbed meteorological forcings according to their respective uncertainties. Crocus simulations driven by operational meteorological forecasts from the Canadian Global Environmental Multiscale model at 10 km spatial resolution were compared to continuous daily SWE measurements over Québec, North-Eastern Canada (56° - 45°N). The results show a mean bias of the maximum SWE overestimated by 16% with variations up to +32%. This observed large variability could lead to dramatic consequences on spring flood forecasts. Results of Crocus-DMRT-ML coupling compared to surface-based TB measurements (at 11, 19 and 37 GHz) show that the Crocus snowpack microstructure described by sticky hard spheres within DMRT has to be scaled by a snow stickiness of 0.18, significantly reducing the overall RMSE of simulated TBs. The ability of assimilation of daily TBs to correct the simulated SWE is first presented through twin experiments with synthetic data, and then with AMSR-2 satellite time series of TBs along the winter taking into account atmospheric and forest canopy interferences (absorption and emission). The differences between TBs at 19-37 GHz and at 11-19 GHz, in vertical polarization, were assimilated. This assimilation test with synthetic data gives a SWE RMSE reduced by a factor of 2 after assimilation. Assimilation of AMSR-2 TBs shows improvement in SWE retrievals compared to continuous in-situ SWE measurements. The accuracy is discussed as a function of boreal forest density and LAI (MODIS-based data), having significant effects.

Comparison of non-invasive assessment of liver fibrosis in patients with alpha1-antitrypsin deficiency using magnetic resonance elastography (MRE), acoustic radiation force impulse (ARFI) Quantification, and 2D-shear wave elastography (2D-SWE).

PubMed

Reiter, Rolf; Wetzel, Martin; Hamesch, Karim; Strnad, Pavel; Asbach, Patrick; Haas, Matthias; Siegmund, Britta; Trautwein, Christian; Hamm, Bernd; Klatt, Dieter; Braun, Jürgen; Sack, Ingolf; Tzschätzsch, Heiko

2018-01-01

Although it has been known for decades that patients with alpha1-antitrypsin deficiency (AATD) have an increased risk of cirrhosis and hepatocellular carcinoma, limited data exist on non-invasive imaging-based methods for assessing liver fibrosis such as magnetic resonance elastography (MRE) and acoustic radiation force impulse (ARFI) quantification, and no data exist on 2D-shear wave elastography (2D-SWE). Therefore, the purpose of this study is to evaluate and compare the applicability of different elastography methods for the assessment of AATD-related liver fibrosis. Fifteen clinically asymptomatic AATD patients (11 homozygous PiZZ, 4 heterozygous PiMZ) and 16 matched healthy volunteers were examined using MRE and ARFI quantification. Additionally, patients were examined with 2D-SWE. A high correlation is evident for the shear wave speed (SWS) determined with different elastography methods in AATD patients: 2D-SWE/MRE, ARFI quantification/2D-SWE, and ARFI quantification/MRE (R = 0.8587, 0.7425, and 0.6914, respectively; P≤0.0089). Four AATD patients with pathologically increased SWS were consistently identified with all three methods-MRE, ARFI quantification, and 2D-SWE. The high correlation and consistent identification of patients with pathologically increased SWS using MRE, ARFI quantification, and 2D-SWE suggest that elastography has the potential to become a suitable imaging tool for the assessment of AATD-related liver fibrosis. These promising results provide motivation for further investigation of non-invasive assessment of AATD-related liver fibrosis using elastography.

Snow Process Estimation Over the Extratropical Andes Using a Data Assimilation Framework Integrating MERRA Data and Landsat Imagery

NASA Technical Reports Server (NTRS)

Cortes, Gonzalo; Girotto, Manuela; Margulis, Steven

2016-01-01

A data assimilation framework was implemented with the objective of obtaining high resolution retrospective snow water equivalent (SWE) estimates over several Andean study basins. The framework integrates Landsat fractional snow covered area (fSCA) images, a land surface and snow depletion model, and the Modern Era Retrospective Analysis for Research and Applications (MERRA) reanalysis as a forcing data set. The outputs are SWE and fSCA fields (1985-2015) at a resolution of 90 m that are consistent with the observed depletion record. Verification using in-situ snow surveys showed significant improvements in the accuracy of the SWE estimates relative to forward model estimates, with increases in correlation (0.49-0.87) and reductions in root mean square error (0.316 m to 0.129 m) and mean error (-0.221 m to 0.009 m). A sensitivity analysis showed that the framework is robust to variations in physiography, fSCA data availability and a priori precipitation biases. Results from the application to the headwater basin of the Aconcagua River showed how the forward model versus the fSCA-conditioned estimate resulted in different quantifications of the relationship between runoff and SWE, and different correlation patterns between pixel-wise SWE and ENSO. The illustrative results confirm the influence that ENSO has on snow accumulation for Andean basins draining into the Pacific, with ENSO explaining approximately 25% of the variability in near-peak (1 September) SWE values. Our results show how the assimilation of fSCA data results in a significant improvement upon MERRA-forced modeled SWE estimates, further increasing the utility of the MERRA data for high-resolution snow modeling applications.

Motor impulsivity in APP-SWE mice: a model of Alzheimer's disease.

PubMed

Adriani, Walter; Ognibene, Elisa; Heuland, Emilie; Ghirardi, Orlando; Caprioli, Antonio; Laviola, Giovanni

2006-09-01

Among transgenic mouse models of Alzheimer's disease, APP-SWE mice have been shown to develop beta-amyloid plaques and to exhibit progressive impairment of cognitive function. Human Alzheimer's disease, however, also includes secondary clinical manifestations, spanning from hyperactivity to agitation. The aim of this study was a better characterization of motor impulsivity in APP-SWE mice, observed at 12 months of age, when levels of soluble beta-amyloid are elevated and beta-amyloid neuritic plaques start to appear. Mice were tested for spatial learning abilities in the Morris water maze (seven daily sessions, four trials per day). The distance traveled to reach the hidden platform showed a learning curve in both groups. This profile, however, was somewhat delayed in APP-SWE mice, thus confirming slightly impaired spatial capacities. To evaluate motor impulsivity, animals were trained to nose-poke for a food reward, which was delivered after a waiting interval that increased over days (15-60 s). Further nose-poking during this signaled waiting interval resulted in food-reward loss and electric-shock punishment. APP-SWE mice received an increased quantity of punishment and were able to earn fewer food rewards, suggesting inability to wait already at the lowest delay. After the animals were killed, prefrontal cortex samples were assessed for neurochemical parameters. Serotonin turnover was elevated in the prefrontal cortex of APP-SWE mice compared with controls. The results clearly confirm cognitive deficits, and are consistent with the hypothesis of reduced behavioral-inhibition abilities. Together with recent findings, APP-SWE mice emerge as a suitable animal model, characterized by a number of specific behavioral alterations, resembling primary and secondary symptoms of human Alzheimer's disease.

Enhancement of Calibrachoa growth, secondary metabolites and bioactivity using seaweed extracts.

PubMed

Elansary, Hosam O; Norrie, Jeff; Ali, Hayssam M; Salem, Mohamed Z M; Mahmoud, Eman A; Yessoufou, Kowiyou

2016-09-02

Calibrachoa x hybrida (Solanaceae) cultivars are widely used in North and South America as ornamental plants. Their potential as a source of antimicrobial compounds might be enhanced by seaweed extract (SWE) applications. SWE of Ascophyllum nodosum were applied at 5 and 7 ml/L as a soil drench or foliar spray on Calibrachoa cultivars of Superbells® 'Dreamsicle' (CHSD) and Superbells® 'Frost Fire' (CHSF). The total phenolics, tannins and antioxidants composition as well as specific flavonols in leaf extracts were determined. Further, the chemical composition of SWE was assessed. The drench and foliar SWE treatments significantly enhanced Calibrachoa cultivars leaf number and area, dry weight, plant height, antioxidant capacity as well as phenolic, flavonols and tannin content. The increased growth and composition of phenols, flavonols and tannins was attributed to the stimulatory effects of SWE mineral composition. The antifungal activity of Calibrachoa cultivars was significantly enhanced following SWE treatments and the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) were in the range of 0.07-0.31 mg/ml and from 0.16 to 0.56 mg/ml, respectively. Moreover, antibacterial activity was significantly increased and the MIC and minimum bactericidal concentration (MBC) measurements were in the range of 0.06-0.23 mg/ml and from 0.10 to 0.44 mg/ml, respectively. The most sensitive fungus to SWE treatments was C. albicans and the most sensitive bacterium was E. cloacae. The results suggest that enhanced antifungal and antibacterial activities might be attributed to significant increases of phenolic, flavonols and tannin contents, which ultimately enhance the potential of Calibrachoa as a natural source of alternative antibiotics.

Observed SWE trends and climate analysis for Northwest Pacific North America: validation for future projection of SWE using the CRCM and VIC

NASA Astrophysics Data System (ADS)

Bennett, K. E.; Bronaugh, D.; Rodenhuis, D.

2008-12-01

Observational databases of snow water equivalent (SWE) have been collected from Alaska, western US states and the Canadian provinces of British Columbia, Alberta, Saskatchewan, and territories of NWT, and the Yukon. These databases were initially validated to remove inconsistencies and errors in the station records, dates or the geographic co-ordinates of the station. The cleaned data was then analysed for historical (1950 to 2006) trend using emerging techniques for trend detection based on (first of the month) estimates for January to June. Analysis of SWE showed spatial variability in the count of records across the six month time period, and this study illustrated differences between Canadian and US (or the north and south) collection. Two different data sets (one gridded and one station) were then used to analyse April 1st records, for which there was the greatest spatial spread of station records for analysis with climate information. Initial results show spatial variability (in both magnitude and direction of trend) for trend results, and climate correlations and principal components indicate different drivers of change in SWE across the western US, Canada and north to Alaska. These results will be used to validate future predictions of SWE that are being undertaken using the Canadian Regional Climate Model (CRCM) and the Variable Infiltration Capacity (VIC) hydrologic model for Western Northern America (CRCM) and British Columbia (VIC).

Using machine learning for real-time estimates of snow water equivalent in the watersheds of Afghanistan

NASA Astrophysics Data System (ADS)

Bair, Edward H.; Abreu Calfa, Andre; Rittger, Karl; Dozier, Jeff

2018-05-01

In the mountains, snowmelt often provides most of the runoff. Operational estimates use imagery from optical and passive microwave sensors, but each has its limitations. An accurate approach, which we validate in Afghanistan and the Sierra Nevada USA, reconstructs spatially distributed snow water equivalent (SWE) by calculating snowmelt backward from a remotely sensed date of disappearance. However, reconstructed SWE estimates are available only retrospectively; they do not provide a forecast. To estimate SWE throughout the snowmelt season, we consider physiographic and remotely sensed information as predictors and reconstructed SWE as the target. The period of analysis matches the AMSR-E radiometer's lifetime from 2003 to 2011, for the months of April through June. The spatial resolution of the predictions is 3.125 km, to match the resolution of a microwave brightness temperature product. Two machine learning techniques - bagged regression trees and feed-forward neural networks - produced similar mean results, with 0-14 % bias and 46-48 mm RMSE on average. Nash-Sutcliffe efficiencies averaged 0.68 for all years. Daily SWE climatology and fractional snow-covered area are the most important predictors. We conclude that these methods can accurately estimate SWE during the snow season in remote mountains, and thereby provide an independent estimate to forecast runoff and validate other methods to assess the snow resource.

Snow Water Equivalent Variations across the western United States and its relation to of El Niño Southern Oscillation

NASA Astrophysics Data System (ADS)

Miller, W. P.; Thakur, B.; Kalra, A.; Lamb, K. W.; Fayne, J.; Tootle, G. A.; Lakshmi, V.

2017-12-01

With the recent increase in global mean temperature Western US has undergone significant decline in snowpack which is the primary source of fresh water for the region. Studies suggests the decline in snowpack also being coupled with different El Niño Southern Oscillation (ENSO) phases. The study includes 1 March, 1 April and 1 May Snow Water Equivalent (SWE) data of 56 years period (1961-2016) for the estimation of long term changes. The current study also estimates monthly snow water equivalent (SWE) variations during different ENSO phases. Mann-Kendall test was utilized for trend detection while the step was evaluated with the Pettitt's test. Kolmogorov - Smirnov test was also utilized to evaluate the differences in the SWE data distribution during different ENSO phases. The results indicated both decreasing trends and decreasing shifts in majority of the SWE stations. The decline in SWE varied with the ENSO phases and also varied spatially following the geography of the region. KS tests suggested northern regions of Western US having variations in cumulative distribution function during El Niño and non- El Niño years as compared to other regions suggesting the northern regions being more impacted by ENSO phases. This analysis can bring insights into the spatiotemporal SWE variations and lead to the better reliability on snowpack for water management issues.

Environmental Monitoring Using Sensor Networks

NASA Astrophysics Data System (ADS)

Yang, J.; Zhang, C.; Li, X.; Huang, Y.; Fu, S.; Acevedo, M. F.

2008-12-01

Environmental observatories, consisting of a variety of sensor systems, computational resources and informatics, are important for us to observe, model, predict, and ultimately help preserve the health of the nature. The commoditization and proliferation of coin-to-palm sized wireless sensors will allow environmental monitoring with unprecedented fine spatial and temporal resolution. Once scattered around, these sensors can identify themselves, locate their positions, describe their functions, and self-organize into a network. They communicate through wireless channel with nearby sensors and transmit data through multi-hop protocols to a gateway, which can forward information to a remote data server. In this project, we describe an environmental observatory called Texas Environmental Observatory (TEO) that incorporates a sensor network system with intertwined wired and wireless sensors. We are enhancing and expanding the existing wired weather stations to include wireless sensor networks (WSNs) and telemetry using solar-powered cellular modems. The new WSNs will monitor soil moisture and support long-term hydrologic modeling. Hydrologic models are helpful in predicting how changes in land cover translate into changes in the stream flow regime. These models require inputs that are difficult to measure over large areas, especially variables related to storm events, such as soil moisture antecedent conditions and rainfall amount and intensity. This will also contribute to improve rainfall estimations from meteorological radar data and enhance hydrological forecasts. Sensor data are transmitted from monitoring site to a Central Data Collection (CDC) Server. We incorporate a GPRS modem for wireless telemetry, a single-board computer (SBC) as Remote Field Gateway (RFG) Server, and a WSN for distributed soil moisture monitoring. The RFG provides effective control, management, and coordination of two independent sensor systems, i.e., a traditional datalogger-based wired sensor system and the WSN-based wireless sensor system. The RFG also supports remote manipulation of the devices in the field such as the SBC, datalogger, and WSN. Sensor data collected from the distributed monitoring stations are stored in a database (DB) Server. The CDC Server acts as an intermediate component to hide the heterogeneity of different devices and support data validation required by the DB Server. Daemon programs running on the CDC Server pre-process the data before it is inserted into the database, and periodically perform synchronization tasks. A SWE-compliant data repository is installed to enable data exchange, accepting data from both internal DB Server and external sources through the OGC web services. The web portal, i.e. TEO Online, serves as a user-friendly interface for data visualization, analysis, synthesis, modeling, and K-12 educational outreach activities. It also provides useful capabilities for system developers and operators to remotely monitor system status and remotely update software and system configuration, which greatly simplifies the system debugging and maintenance tasks. We also implement Sensor Observation Services (SOS) at this layer, conforming to the SWE standard to facilitate data exchange. The standard SensorML/O&M data representation makes it easy to integrate our sensor data into the existing Geographic Information Systems (GIS) web services and exchange the data with other organizations.

The role of shear wave elastography in the assessment of placenta previa-accreta.

PubMed

Alıcı Davutoglu, Ebru; Ariöz Habibi, Hatice; Ozel, Ayşegül; Yuksel, Mehmet Aytac; Adaletli, Ibrahim; Madazlı, Riza

2018-06-01

To evaluate the value of shear wave elastography (SWE) in the prediction of morbidly adherent placenta. Forty-three women with normal placental location and 26 women with anteriorly localized placenta previa were recruited for this case-control study. Placental elasticity values in both the groups were determined by SWE imaging. SWE values were higher in the placenta previa group in all regions than in normal localized placentas (p < .01). However, there was no statistically significant difference between SWE values of placenta previa with and without morbidly adherent placenta (p > .05). Placental stiffness is significantly higher in placenta previa than normal localized placentas. However, we could not demonstrate any statistically significant difference in the elasticity values between the placenta previa with and without accreta.

Evaluating the Impact of Vegetation Cover and Atmospheric Characteristics on the Estimation of Snow Water Equivalent from Spaceborne Microwave Radiometry

NASA Technical Reports Server (NTRS)

Choudhury, Bhaskar J.; Foster, James L.

2010-01-01

A radiative transfer model for estimating snow water equivalent (SWE, mm) from satellite-observed brightness temperature (K) at 19 and 37 GHz (respectively, T(sub B(sub, sat,19)) and T(sub B(sub, sat,37)) over partially forested area is presented, as an extension of a previously published model, by considering scattering of radiation within the canopy. For the specific case of dense vegetation covering fractional area f, the model can be written as, SWE = alpha{ A. delta (T(sub B(sub, sat)) + B - C. f}/(l f), where delta T(sub B(sub, sat)), is the difference of T(sub B(sub, sat,19)) and T(sub B(sub, sat,37)), alpha(mm/K) is the slope of SWE vs. brightness temperature difference at 19 and 37 GHz that would be obtained by ignoring the presence of atmosphere, delta(T(sub B)sub g)), for a homogeneous snow cover (which varies with grain size). The parameters A, B, and C, are determined primarily by atmospheric characteristics, and for a likely range of atmospheric conditions appear to be in the range of, respectively, 1.15-1.63, 0.69-2.84 K and 0.59-2.39 K. Ignoring atmospheric correction would introduce bias towards underestimation of SWE (and also, snow cover area and snow depth). Increasing cloud liquid water path (L) has the effect of increasing A, and ignoring this variation of A with L would have the impact of biasing the estimate of SWE (and snow extent). Such biasing is further exacerbated with increasing f, because of the appearance of term (l-f) in the denominator. The impact of ignoring the intercept parameters (B and C) would be noticeable at low values of SWE (appearing as a bias towards underestimation of SWE), which has been determined to be about 6 mm for average environmental conditions. The uncertainty in estimating SWE due to variations in the atmospheric characteristics is likely to be less than 15%, but could be up to 25% for non-vegetated snow-covered areas. Better estimates of SWE (and snow extent) would be obtained by adjusting the parameters of the above model to regional differences in the atmospheric characteristics. The biases in determining SWE arising due to variations in atmospheric conditions and due to changes in fractional forest cover are not independent, since they interact as {A/(l-f)}. The present calculations also show that improvement in determining snow cover area from the microwave data is likely to occur when these data are corrected for atmospheric effects, as demonstrated by a specific case study.

Liver elastography malignancy prediction score for noninvasive characterization of focal liver lesions.

PubMed

Grgurevic, Ivica; Bokun, Tomislav; Salkic, Nermin N; Brkljacic, Boris; Vukelić-Markovic, Mirjana; Stoos-Veic, Tajana; Aralica, Gorana; Rakic, Mislav; Filipec-Kanizaj, Tajana; Berzigotti, Annalisa

2018-06-01

To analyse elastographic characteristics of focal liver lesions (FLL)s and diagnostic performance of real-time two-dimensional shear-wave elastography (RT-2D-SWE) in order to differentiate benign and malignant FLLs. Consecutive patients diagnosed with FLL by abdominal ultrasound (US) underwent RT-2D-SWE of FLL and non-infiltrated liver by intercostal approach over the right liver lobe. The nature of FLL was determined by diagnostic work-up, including at least one contrast-enhanced imaging modality (MDCT/MRI), check-up of target organs when metastatic disease was suspected and FLL biopsy in inconclusive cases. We analysed 196 patients (median age 60 [range 50-68], 50.5% males) with 259 FLLs (57 hepatocellular carcinomas, 17 cholangiocarcinomas, 94 metastases, 71 haemangiomas, 20 focal nodular hyperplasia) of which 70 (27%) were in cirrhotic liver. Malignant lesions were stiffer (P < .001) with higher variability in intralesional stiffness (P = .001). The best performing cut-off of lesion stiffness was 22.3 kPa (sensitivity 83%; specificity 86%; positive predictive value [PPV] 91.5%; negative predictive value [NPV] 73%) for malignancy. Lesion stiffness <14 kPa had NPV of 96%, while values >32.5 kPa had PPV of 96% for malignancy. Lesion stiffness, lesion/liver stiffness ratio and lesion stiffness variability significantly predicted malignancy in stepwise logistic regression (P < .05), and were used to construct a new Liver Elastography Malignancy Prediction (LEMP) score with accuracy of 96.1% in validation cohort (online calculator available at http://bit.do/lemps). The comprehensive approach demonstrated in this study enables correct differentiation of benign and malignant FLL in 96% of patients by using RT-2D-SWE. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Uncertainty in Estimates of Net Seasonal Snow Accumulation on Glaciers from In Situ Measurements

NASA Astrophysics Data System (ADS)

Pulwicki, A.; Flowers, G. E.; Radic, V.

2017-12-01

Accurately estimating the net seasonal snow accumulation (or "winter balance") on glaciers is central to assessing glacier health and predicting glacier runoff. However, measuring and modeling snow distribution is inherently difficult in mountainous terrain, resulting in high uncertainties in estimates of winter balance. Our work focuses on uncertainty attribution within the process of converting direct measurements of snow depth and density to estimates of winter balance. We collected more than 9000 direct measurements of snow depth across three glaciers in the St. Elias Mountains, Yukon, Canada in May 2016. Linear regression (LR) and simple kriging (SK), combined with cross correlation and Bayesian model averaging, are used to interpolate estimates of snow water equivalent (SWE) from snow depth and density measurements. Snow distribution patterns are found to differ considerably between glaciers, highlighting strong inter- and intra-basin variability. Elevation is found to be the dominant control of the spatial distribution of SWE, but the relationship varies considerably between glaciers. A simple parameterization of wind redistribution is also a small but statistically significant predictor of SWE. The SWE estimated for one study glacier has a short range parameter (90 m) and both LR and SK estimate a winter balance of 0.6 m w.e. but are poor predictors of SWE at measurement locations. The other two glaciers have longer SWE range parameters ( 450 m) and due to differences in extrapolation, SK estimates are more than 0.1 m w.e. (up to 40%) lower than LR estimates. By using a Monte Carlo method to quantify the effects of various sources of uncertainty, we find that the interpolation of estimated values of SWE is a larger source of uncertainty than the assignment of snow density or than the representation of the SWE value within a terrain model grid cell. For our study glaciers, the total winter balance uncertainty ranges from 0.03 (8%) to 0.15 (54%) m w.e. depending primarily on the interpolation method. Despite the challenges associated with accurately and precisely estimating winter balance, our results are consistent with the previously reported regional accumulation gradient.

Snowpack spatial variability: Towards understanding its effect on remote sensing measurements and snow slope stability

NASA Astrophysics Data System (ADS)

Marshall, Hans-Peter

The distribution of water in the snow-covered areas of the world is an important climate change indicator, and it is a vital component of the water cycle. At local and regional scales, the snow water equivalent (SWE), the amount of liquid water a given area of the snowpack represents, is very important for water resource management, flood forecasting, and prediction of available hydropower energy. Measurements from only a few automatic weather stations, such as the SNOTEL network, or sparse manual snowpack measurements are typically extrapolated for estimating SWE over an entire basin. Widespread spatial variability in the distribution of SWE and snowpack stratigraphy at local scales causes large errors in these basin estimates. Remote sensing measurements offer a promising alternative, due to their large spatial coverage and high temporal resolution. Although snow cover extent can currently be estimated from remote sensing data, accurately quantifying SWE from remote sensing measurements has remained difficult, due to a high sensitivity to variations in grain size and stratigraphy. In alpine snowpacks, the large degree of spatial variability of snowpack properties and geometry, caused by topographic, vegetative, and microclimatic effects, also makes prediction of snow avalanches very difficult. Ground-based radar and penetrometer measurements can quickly and accurately characterize snowpack properties and SWE in the field. A portable lightweight radar was developed, and allows a real-time estimate of SWE to within 10%, as well as measurements of depths of all major density transitions within the snowpack. New analysis techniques developed in this thesis allow accurate estimates of mechanical properties and an index of grain size to be retrieved from the SnowMicroPenetrometer. These two tools together allow rapid characterization of the snowpack's geometry, mechanical properties, and SWE, and are used to guide a finite element model to study the stress distribution on a slope. The ability to accurately characterize snowpack properties at much higher resolutions and spatial extent than previously possible will hopefully help lead to a more complete understanding of spatial variability, its effect on remote sensing measurements and snow slope stability, and result in improvements in avalanche prediction and accuracy of SWE estimates from space.

Web-enabling technologies for the factory floor: a web-enabling strategy for emanufacturing

NASA Astrophysics Data System (ADS)

Velez, Ricardo; Lastra, Jose L. M.; Tuokko, Reijo O.

2001-10-01

This paper is intended to address the different technologies available for Web-enabling of the factory floor. It will give an overview of the importance of Web-enabling of the factory floor, in the application of the concepts of flexible and intelligent manufacturing, in conjunction with e-commerce. As a last section, it will try to define a Web-enabling strategy for the application in eManufacturing. This is made under the scope of the electronics manufacturing industry, so every application, technology or related matter is presented under such scope.

Non-invasive assessment of liver fibrosis using two-dimensional shear wave elastography in patients with autoimmune liver diseases

PubMed Central

Zeng, Jie; Huang, Ze-Ping; Zheng, Jian; Wu, Tao; Zheng, Rong-Qin

2017-01-01

AIM To determine the diagnostic accuracy of two-dimensional shear wave elastography (2D-SWE) for the non-invasive assessment of liver fibrosis in patients with autoimmune liver diseases (AILD) using liver biopsy as the reference standard. METHODS Patients with AILD who underwent liver biopsy and 2D-SWE were consecutively enrolled. Receiver operating characteristic (ROC) curves were constructed to assess the overall accuracy and to identify optimal cut-off values. RESULTS The characteristics of the diagnostic performance were determined for 114 patients with AILD. The areas under the ROC curves for significant fibrosis, severe fibrosis, and cirrhosis were 0.85, 0.85, and 0.86, respectively, and the optimal cut-off values associated with significant fibrosis (≥ F2), severe fibrosis (≥ F3), and cirrhosis (F4) were 9.7 kPa, 13.2 kPa and 16.3 kPa, respectively. 2D-SWE showed sensitivity values of 81.7% for significant fibrosis, 83.0% for severe fibrosis, and 87.0% for cirrhosis, and the respective specificity values were 81.3%, 74.6%, and 80.2%. The overall concordance rate of the liver stiffness measurements obtained using 2D-SWE vs fibrosis stages was 53.5%. CONCLUSION 2D-SWE showed promising diagnostic performance for assessing liver fibrosis stages and exhibited high cut-off values in patients with AILD. Low overall concordance rate was observed in the liver stiffness measurements obtained using 2D-SWE vs fibrosis stages. PMID:28765706

Performance of 2-D shear wave elastography in liver fibrosis assessment compared with serologic tests and transient elastography in clinical routine.

PubMed

Bota, Simona; Paternostro, Rafael; Etschmaier, Alexandra; Schwarzer, Remy; Salzl, Petra; Mandorfer, Mattias; Kienbacher, Christian; Ferlitsch, Monika; Reiberger, Thomas; Trauner, Michael; Peck-Radosavljevic, Markus; Ferlitsch, Arnulf

2015-09-01

Liver stiffness values assessed with 2-D shear wave elastography (SWE), transient elastography (TE) and simple serologic tests were compared with respect to non-invasive assessment in a cohort of 127 consecutive patients with chronic liver diseases. The rate of reliable liver stiffness measurements was significantly higher with 2-D SWE than with TE: 99.2% versus 74.8%, p < 0.0001 (different reliability criteria used, according to current recommendations). In univariate analysis, liver stiffness measured with 2-D SWE correlated best with fibrosis stage estimated with TE (r = 0.699, p < 0.0001), followed by Forns score (r = 0.534, p < 0.0001) and King's score (r = 0.512, p < 0.0001). However, in multivariate analysis, only 2-D SWE-measured values remained correlated with fibrosis stage (p < 0.0001). The optimal 2-D SWE cutoff values for predicting significant fibrosis were 8.03 kPa for fibrosis stage ≥2 (area under the receiver operating characteristic curve = 0.832) and 13.1 kPa for fibrosis stage 4 (area under the receiver operating characteristic curve = 0.915), respectively. In conclusion, 2-D SWE can be used to obtain reliable liver stiffness measurements in almost all patients and performs very well in predicting the presence of liver cirrhosis. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Shear wave elastography of placenta: in vivo quantitation of placental elasticity in preeclampsia

PubMed Central

Kılıç, Fahrettin; Kayadibi, Yasemin; Yüksel, Mehmet Aytaç; Adaletli, İbrahim; Ustabaşıoğlu, Fethi Emre; Öncül, Mahmut; Madazlı, Rıza; Yılmaz, Mehmet Halit; Mihmanlı, İsmail; Kantarcı, Fatih

2015-01-01

PURPOSE We aimed to evaluate the utility of shear wave elastography (SWE) for assessing the placenta in preeclampsia disease. METHODS A total of 50 pregnant women in the second or third trimester (23 preeclampsia patients and 27 healthy control subjects) were enrolled in the study. Obstetrical grayscale and Doppler ultrasonography, SWE findings of placenta, and prenatal/postnatal clinical data were analyzed and the best SWE cutoff value which represents the diagnosis of preeclampsia was determined. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of preeclampsia were calculated based on SWE measurements. RESULTS Mean stiffness values were much higher in preeclamptic placentas in all regions and layers than in normal controls. The most significant difference was observed in the central placental area facing the fetus where the umbilical cord inserts, with a median of 21 kPa (range, 3–71 kPa) for preeclampsia and 4 kPa (range, 1.5–14 kPa) for the control group (P < 0.01). The SWE data showed a moderate correlation with the uterine artery resistivity and pulsatility indices. The cutoff value maximizing the accuracy of diagnosis was 7.35 kPa (area under curve, 0.895; 95% confidence interval, 0.791–0.998); sensitivity, specificity, PPV, NPV, and accuracy were 90%, 86%, 82%, 92%, and 88%, respectively. CONCLUSION Stiffness of the placenta is significantly higher in patients with preeclampsia. SWE appears to be an assistive diagnostic technique for placenta evaluation in preeclampsia. PMID:25858523

Non-invasive assessment of liver fibrosis using two-dimensional shear wave elastography in patients with autoimmune liver diseases.

PubMed

Zeng, Jie; Huang, Ze-Ping; Zheng, Jian; Wu, Tao; Zheng, Rong-Qin

2017-07-14

To determine the diagnostic accuracy of two-dimensional shear wave elastography (2D-SWE) for the non-invasive assessment of liver fibrosis in patients with autoimmune liver diseases (AILD) using liver biopsy as the reference standard. Patients with AILD who underwent liver biopsy and 2D-SWE were consecutively enrolled. Receiver operating characteristic (ROC) curves were constructed to assess the overall accuracy and to identify optimal cut-off values. The characteristics of the diagnostic performance were determined for 114 patients with AILD. The areas under the ROC curves for significant fibrosis, severe fibrosis, and cirrhosis were 0.85, 0.85, and 0.86, respectively, and the optimal cut-off values associated with significant fibrosis (≥ F2), severe fibrosis (≥ F3), and cirrhosis (F4) were 9.7 kPa, 13.2 kPa and 16.3 kPa, respectively. 2D-SWE showed sensitivity values of 81.7% for significant fibrosis, 83.0% for severe fibrosis, and 87.0% for cirrhosis, and the respective specificity values were 81.3%, 74.6%, and 80.2%. The overall concordance rate of the liver stiffness measurements obtained using 2D-SWE vs fibrosis stages was 53.5%. 2D-SWE showed promising diagnostic performance for assessing liver fibrosis stages and exhibited high cut-off values in patients with AILD. Low overall concordance rate was observed in the liver stiffness measurements obtained using 2D-SWE vs fibrosis stages.

Validation of Shear Wave Elastography in Skeletal Muscle

PubMed Central

Eby, Sarah F.; Song, Pengfei; Chen, Shigao; Chen, Qingshan; Greenleaf, James F.; An, Kai-Nan

2013-01-01

Skeletal muscle is a very dynamic tissue, thus accurate quantification of skeletal muscle stiffness throughout its functional range is crucial to improve the physical functioning and independence following pathology. Shear wave elastography (SWE) is an ultrasound-based technique that characterizes tissue mechanical properties based on the propagation of remotely induced shear waves. The objective of this study is to validate SWE throughout the functional range of motion of skeletal muscle for three ultrasound transducer orientations. We hypothesized that combining traditional materials testing (MTS) techniques with SWE measurements will show increased stiffness measures with increasing tensile load, and will correlate well with each other for trials in which the transducer is parallel to underlying muscle fibers. To evaluate this hypothesis, we monitored the deformation throughout tensile loading of four porcine brachialis whole-muscle tissue specimens, while simultaneously making SWE measurements of the same specimen. We used regression to examine the correlation between Young's modulus from MTS and shear modulus from SWE for each of the transducer orientations. We applied a generalized linear model to account for repeated testing. Model parameters were estimated via generalized estimating equations. The regression coefficient was 0.1944, with a 95% confidence interval of (0.1463 – 0.2425) for parallel transducer trials. Shear waves did not propagate well for both the 45° and perpendicular transducer orientations. Both parallel SWE and MTS showed increased stiffness with increasing tensile load. This study provides the necessary first step for additional studies that can evaluate the distribution of stiffness throughout muscle. PMID:23953670

3-Dimensional shear wave elastography of breast lesions

PubMed Central

Chen, Ya-ling; Chang, Cai; Zeng, Wei; Wang, Fen; Chen, Jia-jian; Qu, Ning

2016-01-01

Abstract Color patterns of 3-dimensional (3D) shear wave elastography (SWE) is a promising method in differentiating tumoral nodules recently. This study was to evaluate the diagnostic accuracy of color patterns of 3D SWE in breast lesions, with special emphasis on coronal planes. A total of 198 consecutive women with 198 breast lesions (125 malignant and 73 benign) were included, who underwent conventional ultrasound (US), 3D B-mode, and 3D SWE before surgical excision. SWE color patterns of Views A (transverse), T (sagittal), and C (coronal) were determined. Sensitivity, specificity, and the area under the receiver operating characteristic curve (AUC) were calculated. Distribution of SWE color patterns was significantly different between malignant and benign lesions (P = 0.001). In malignant lesions, “Stiff Rim” was significantly more frequent in View C (crater sign, 60.8%) than in View A (51.2%, P = 0.013) and View T (54.1%, P = 0.035). AUC for combination of “Crater Sign” and conventional US was significantly higher than View A (0.929 vs 0.902, P = 0.004) and View T (0.929 vs 0.907, P = 0.009), and specificity significantly increased (90.4% vs 78.1%, P = 0.013) without significant change in sensitivity (85.6% vs 88.0%, P = 0.664) as compared with conventional US. In conclusion, combination of conventional US with 3D SWE color patterns significantly increased diagnostic accuracy, with “Crater Sign” in coronal plane of the highest value. PMID:27684820

Topography and vegetation as predictors of snow water equivalent across the alpine treeline ecotone at Lee Ridge, Glacier National Park, Montana, U.S.A.

USGS Publications Warehouse

Geddes, C.A.; Brown, D.G.; Fagre, D.B.

2005-01-01

We derived and implemented two spatial models of May snow water equivalent (SWE) at Lee Ridge in Glacier National Park, Montana. We used the models to test the hypothesis that vegetation structure is a control on snow redistribution at the alpine treeline ecotone (ATE). The statistical models were derived using stepwise and "best" subsets regression techniques. The first model was derived from field measurements of SWE, topography, and vegetation taken at 27 sample points. The second model was derived using GIS-based measures of topography and vegetation. Both the field- (R² = 0.93) and GIS-based models (R² = 0.69) of May SWE included the following variables: site type (based on vegetation), elevation, maximum slope, and general slope aspect. Site type was identified as the most important predictor of SWE in both models, accounting for 74.0% and 29.5% of the variation, respectively. The GIS-based model was applied to create a predictive map of SWE across Lee Ridge, predicting little snow accumulation on the top of the ridge where vegetation is scarce. The GIS model failed in large depressions, including ephemeral stream channels. The models supported the hypothesis that upright vegetation has a positive effect on accumulation of SWE above and beyond the effects of topography. Vegetation, therefore, creates a positive feedback in which it modifies its, environment and could affect the ability of additional vegetation to become established.

A Walk through TRIDEC's intermediate Tsunami Early Warning System

NASA Astrophysics Data System (ADS)

Hammitzsch, M.; Reißland, S.; Lendholt, M.

2012-04-01

The management of natural crises is an important application field of the technology developed in the project Collaborative, Complex, and Critical Decision-Support in Evolving Crises (TRIDEC), co-funded by the European Commission in its Seventh Framework Programme. TRIDEC is based on the development of the German Indonesian Tsunami Early Warning System (GITEWS) and the Distant Early Warning System (DEWS) providing a service platform for both sensor integration and warning dissemination. In TRIDEC new developments in Information and Communication Technology (ICT) are used to extend the existing platform realising a component-based technology framework for building distributed tsunami warning systems for deployment, e.g. in the North-eastern Atlantic, the Mediterranean and Connected Seas (NEAM) region. The TRIDEC system will be implemented in three phases, each with a demonstrator. Successively, the demonstrators are addressing challenges, such as the design and implementation of a robust and scalable service infrastructure supporting the integration and utilisation of existing resources with accelerated generation of large volumes of data. These include sensor systems, geo-information repositories, simulation tools and data fusion tools. In addition to conventional sensors also unconventional sensors and sensor networks play an important role in TRIDEC. The system version presented is based on service-oriented architecture (SOA) concepts and on relevant standards of the Open Geospatial Consortium (OGC), the World Wide Web Consortium (W3C) and the Organization for the Advancement of Structured Information Standards (OASIS). In this way the system continuously gathers, processes and displays events and data coming from open sensor platforms to enable operators to quickly decide whether an early warning is necessary and to send personalized warning messages to the authorities and the population at large through a wide range of communication channels. The system integrates OGC Sensor Web Enablement (SWE) compliant sensor systems for the rapid detection of hazardous events, like earthquakes, sea level anomalies, ocean floor occurrences, and ground displacements. Using OGC Web Map Service (WMS) and Web Feature Service (WFS) spatial data are utilized to depict the situation picture. The integration of a simulation system to identify affected areas is considered using the OGC Web Processing Service (WPS). Warning messages are compiled and transmitted in the OASIS Common Alerting Protocol (CAP) together with addressing information defined via the OASIS Emergency Data Exchange Language - Distribution Element (EDXL-DE). The first system demonstrator has been designed and implemented to support plausible scenarios demonstrating the treatment of simulated tsunami threats with an essential subset of a National Tsunami Warning Centre (NTWC). The feasibility and the potentials of the implemented approach are demonstrated covering standard operations as well as tsunami detection and alerting functions. The demonstrator presented addresses information management and decision-support processes in a hypothetical natural crisis situation caused by a tsunami in the Eastern Mediterranean. Developments of the system are based to the largest extent on free and open source software (FOSS) components and industry standards. Emphasis has been and will be made on leveraging open source technologies that support mature system architecture models wherever appropriate. All open source software produced is foreseen to be published on a publicly available software repository thus allowing others to reuse results achieved and enabling further development and collaboration with a wide community including scientists, developers, users and stakeholders. This live demonstration is linked with the talk "TRIDEC Natural Crisis Management Demonstrator for Tsunamis" (EGU2012-7275) given in the session "Architecture of Future Tsunami Warning Systems" (NH5.7/ESSI1.7).

A finite element model to study the effect of tissue anisotropy on ex vivo arterial shear wave elastography measurements

NASA Astrophysics Data System (ADS)

Shcherbakova, D. A.; Debusschere, N.; Caenen, A.; Iannaccone, F.; Pernot, M.; Swillens, A.; Segers, P.

2017-07-01

Shear wave elastography (SWE) is an ultrasound (US) diagnostic method for measuring the stiffness of soft tissues based on generated shear waves (SWs). SWE has been applied to bulk tissues, but in arteries it is still under investigation. Previously performed studies in arteries or arterial phantoms demonstrated the potential of SWE to measure arterial wall stiffness—a relevant marker in prediction of cardiovascular diseases. This study is focused on numerical modelling of SWs in ex vivo equine aortic tissue, yet based on experimental SWE measurements with the tissue dynamically loaded while rotating the US probe to investigate the sensitivity of SWE to the anisotropic structure. A good match with experimental shear wave group speed results was obtained. SWs were sensitive to the orthotropy and nonlinearity of the material. The model also allowed to study the nature of the SWs by performing 2D FFT-based and analytical phase analyses. A good match between numerical group velocities derived using the time-of-flight algorithm and derived from the dispersion curves was found in the cross-sectional and axial arterial views. The complexity of solving analytical equations for nonlinear orthotropic stressed plates was discussed.

Smooth muscle cells of penis in the rat: noninvasive quantification with shear wave elastography.

PubMed

Zhang, Jia-Jie; Qiao, Xiao-Hui; Gao, Feng; Bai, Ming; Li, Fan; Du, Lian-Fang; Xing, Jin-Fang

2015-01-01

Smooth muscle cells (SMCs) of cavernosum play an important role in erection. It is of great significance to quantitatively analyze the level of SMCs in penis. In this study, we investigated the feasibility of shear wave elastography (SWE) on evaluating the level of SMCs in penis quantitatively. Twenty healthy male rats were selected. The SWE imaging of penis was carried out and then immunohistochemistry analysis of penis was performed to analyze the expression of alpha smooth muscle actin in penis. The measurement index of SWE examination was tissue stiffness (TS). The measurement index of immunohistochemistry analysis was positive area percentage of alpha smooth muscle actin (AP). Sixty sets of data of TS and AP were obtained. The results showed that TS was significantly correlated with AP and the correlation coefficient was -0.618 (p < 0.001). The result of TS had been plotted against the AP measurements. The relation between the two results has been fitted with quadric curve; the goodness-of-fit index was 0.364 (p < 0.001). The level of SMCs in penis was successfully quantified in vivo with SWE. SWE can be used clinically for evaluating the level of SMCs in penis quantitatively.

Applicability of shear wave elastography of the major salivary glands: values in healthy patients and effects of gender, smoking and pre-compression.

PubMed

Mantsopoulos, Konstantinos; Klintworth, Nils; Iro, Heinrich; Bozzato, Alessandro

2015-09-01

Our aim in this study was to determine normal shear wave elastography (SWE) values for the parenchyma of the major salivary glands and to evaluate the influences of gender, smoking, side and type of gland and varying amounts of ultrasound probe pressure on SWE values. Twenty-five consecutive healthy patients were examined with ultrasound. SWE velocities were measured with acoustic radiation force imaging in the hilum and central region of both glands with "normal" and very low pressure. Mean SWE velocities were 1.854 m/s for the parotid gland and 1.932 m/s for the submandibular gland. No statistically significant differences were detected between males and females, smokers and non-smokers, parotid and submandibular gland and left and right sides. Greater pre-compression with the ultrasound probe resulted in a statistically significant increase in the SWE values of both salivary glands (p < 0.000). The degree of pre-compression by the ultrasound transducer should be standardized, so that the reliability and reproducibility of this innovative method can be improved. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

GeoSciML v3.0 - a significant upgrade of the CGI-IUGS geoscience data model

NASA Astrophysics Data System (ADS)

Raymond, O.; Duclaux, G.; Boisvert, E.; Cipolloni, C.; Cox, S.; Laxton, J.; Letourneau, F.; Richard, S.; Ritchie, A.; Sen, M.; Serrano, J.-J.; Simons, B.; Vuollo, J.

2012-04-01

GeoSciML version 3.0 (http://www.geosciml.org), released in late 2011, is the latest version of the CGI-IUGS* Interoperability Working Group geoscience data interchange standard. The new version is a significant upgrade and refactoring of GeoSciML v2 which was released in 2008. GeoSciML v3 has already been adopted by several major international interoperability initiatives, including OneGeology, the EU INSPIRE program, and the US Geoscience Information Network, as their standard data exchange format for geoscience data. GeoSciML v3 makes use of recently upgraded versions of several Open Geospatial Consortium (OGC) and ISO data transfer standards, including GML v3.2, SWE Common v2.0, and Observations and Measurements v2 (ISO 19156). The GeoSciML v3 data model has been refactored from a single large application schema with many packages, into a number of smaller, but related, application schema modules with individual namespaces. This refactoring allows the use and future development of modules of GeoSciML (eg; GeologicUnit, GeologicStructure, GeologicAge, Borehole) in smaller, more manageable units. As a result of this refactoring and the integration with new OGC and ISO standards, GeoSciML v3 is not backwardly compatible with previous GeoSciML versions. The scope of GeoSciML has been extended in version 3.0 to include new models for geomorphological data (a Geomorphology application schema), and for geological specimens, geochronological interpretations, and metadata for geochemical and geochronological analyses (a LaboratoryAnalysis-Specimen application schema). In addition, there is better support for borehole data, and the PhysicalProperties model now supports a wider range of petrophysical measurements. The previously used CGI_Value data type has been superseded in favour of externally governed data types provided by OGC's SWE Common v2 and GML v3.2 data standards. The GeoSciML v3 release includes worked examples of best practice in delivering geochemical analytical data using the Observations and Measurements (ISO19156) and SWE Common v2 models. The GeoSciML v3 data model does not include vocabularies to support the data model. However, it does provide a standard pattern to reference controlled vocabulary concepts using HTTP-URIs. The international GeoSciML community has developed distributed RDF-based geoscience vocabularies that can be accessed by GeoSciML web services using the standard pattern recommended in GeoSciML v3. GeoSciML v3 is the first version of GeoSciML that will be accompanied by web service validation tools using Schematron rules. For example, these validation tools may check for compliance of a web service to a particular profile of GeoSciML, or for logical consistency of data content that cannot be enforced by the application schemas. This validation process will support accreditation of GeoSciML services and a higher degree of semantic interoperability. * International Union of Geological Sciences Commission for Management and Application of Geoscience Information (CGI-IUGS)

Snow Water Equivalent Pressure Sensor Performance in a Deep Snow Cover

NASA Astrophysics Data System (ADS)

Johnson, J. B.; Gelvin, A. B.; Schaefer, G. L.

2006-12-01

Accurate measurements of snow water equivalent are important for a variety of water resource management operations. In the western US, real-time SWE measurements are made using snow pillows that can experience errors from snow-bridging, poor installation configuration, and enhanced solar radiation absorption. Snow pillow installations that place the pillow abnormally above or below the surrounding terrain can affect snow catchment. Snow pillows made from dark materials can preferentially absorb solar radiation penetrating the snow causing accelerated melt. To reduce these problems, the NRCS and CRREL developed an electronic SWE sensor to replace the snow pillow. During the winter of 2005-2006 the NRCS/CRREL electronic sensor was deployed at Hogg Pass, Oregon, with a total SWE accumulation of about 1000 mm. The NRCS/CRREL sensor consists of a center panel surrounded by eight outer panels whose purpose is to buffer snow bridging loads. By separately monitoring load cell outputs from the sensor, snow-bridging events are directly measured. A snow-bridging event associated with a 180 mm SWE accumulation in a 24-hour period exhibited a SWE over-measurement of 60% at the sensor edge while the center panel showed less than a 10% effect. Individual load cell outputs were used to determine the most representative SWE value, which was within 5% of the adjacent snow pillow value. During the spring melt the NRCS/CRREL sensor melt recession lagged that of the snow pillow by about a week. Physical examination of the Hogg Pass site indicated that the CRREL sensor results were consistent with snow-on-the-ground observations. The snow pillow experienced accelerated melt because it was installed on a mound above the surrounding terrain and absorbed solar radiation through the snow. SWE pressure sensor accuracy is significantly improved by using an active center panel surrounded by buffer panels, monitoring several individual load cell to detect and correct snow-bridging errors, and reducing the radiation and topographic profile of the sensor.

Added value of shear-wave elastography for evaluation of breast masses detected with screening US imaging.

PubMed

Lee, Su Hyun; Chang, Jung Min; Kim, Won Hwa; Bae, Min Sun; Seo, Mirinae; Koo, Hye Ryoung; Chu, A Jung; Gweon, Hye Mi; Cho, Nariya; Moon, Woo Kyung

2014-10-01

To evaluate the additional value of shear-wave elastography (SWE) to B-mode ultrasonography (US) and to determine an appropriate guideline for the combined assessment of screening US-detected breast masses. This study was conducted with institutional review board approval, and written informed consent was obtained. From March 2010 to February 2012, B-mode US and SWE were performed in 159 US-detected breast masses before biopsy. For each lesion, Breast Imaging Reporting and Data System (BI-RADS) category on B-mode US images and the maximum stiffness color and elasticity values on SWE images were assessed. A guideline for adding SWE data to B-mode US was developed with the retrospective cohort to improve diagnostic performance in sensitivity and specificity and was validated in a distinct prospective cohort of 207 women prior to biopsy. Twenty-one of 159 masses in the development cohort and 12 of 207 breast masses in the validation cohort were malignant. In the development cohort, when BI-RADS category 4a masses showing a dark blue color or a maximum elasticity value of 30 kPa or less on SWE images were downgraded to category 3, specificity increased from 9.4% (13 of 138) to 59.4% (82 of 138) and 57.2% (79 of 138) (P < .001), respectively, without loss in sensitivity (100% [21 of 21]). In the validation cohort, specificity increased from 17.4% (34 of 195) to 62.1% (121 of 195) and 53.3% (104 of 195) (P < .001) respectively, without loss in sensitivity (91.7% [11 of 12]). The addition of SWE to B-mode US improved diagnostic performance with increased specificity for screening US-detected breast masses. BI-RADS category 4a masses detected at US screening that showed a dark blue color or a maximum elasticity value of 30 kPa or less on SWE images can be safely followed up instead of performing biopsy. © RSNA, 2014.

Seaweed extracts and galacto-oligosaccharides improve intestinal health in pigs following Salmonella Typhimurium challenge.

PubMed

Bouwhuis, M A; McDonnell, M J; Sweeney, T; Mukhopadhya, A; O'Shea, C J; O'Doherty, J V

2017-09-01

Pork and pork products are recognised as vehicles of Salmonella Typhimurium infection in humans. Seaweed-derived polysaccharides (SWE) and galacto-oligosaccharides (GOS) have shown to exhibit antimicrobial, prebiotic and immunomodulatory activity. The objective of this study was to assess the effects of dietary GOS and SWE supplementation on reducing S. Typhimurium numbers and intestinal inflammation in vivo. In total, 30 pigs (n=10/treatment, BW 30.9 kg) were randomly assigned to three dietary treatments: (1) basal diet; (2) basal diet+2.5 g GOS/kg diet; (3) basal diet+SWE (containing 180 mg laminarin/kg diet+340 mg fucoidan/kg diet). Following an 11-day dietary adaptation period, pigs were orally challenged with 108 colony-forming units/ml S. Typhimurium (day 0). Pigs remained on their diets for a further 17 days and were then sacrificed for sample collection. The SWE supplementation did not affect S. Typhimurium numbers on days 2 and 4 post-challenge but reduced S. Typhimurium numbers in faecal samples collected day 7 post-challenge (-0.80 log gene copy numbers (GCN)/g faeces) and in caecal and colonic digesta (-0.62 and -0.98 log GCN/g digesta, respectively; P<0.05) compared with the control treatment. Lactobacillus numbers were increased in caecal and colonic digesta after GOS supplementation (+0.70 and +0.35 log GCN/g digesta, respectively; P<0.05). In colonic tissue, both GOS and SWE supplementation resulted in reduced messenger RNA expression levels of interleukin (IL)-6, IL-22, tumour necrosis factor-α and regenerating islet-derived protein 3-γ (P<0.05). It can be concluded that dietary supplementation of SWE reduced faecal and intestinal S. Typhimurium numbers compared with the basal diet, whereas dietary GOS supplementation increased Lactobacillus numbers in caecal and colonic digesta but did not affect S. Typhimurium numbers. Supplementation of GOS and SWE reduced the gene expression of pro-inflammatory cytokines in colonic tissue of pigs after the experimental S. Typhimurium challenge.

Feasibility of transient elastography versus real-time two-dimensional shear wave elastography in difficult-to-scan patients.

PubMed

Staugaard, Benjamin; Christensen, Peer Brehm; Mössner, Belinda; Hansen, Janne Fuglsang; Madsen, Bjørn Stæhr; Søholm, Jacob; Krag, Aleksander; Thiele, Maja

2016-11-01

Transient elastography (TE) is hampered in some patients by failures and unreliable results. We hypothesized that real time two-dimensional shear wave elastography (2D-SWE), the FibroScan XL probe, and repeated TE exams, could be used to obtain reliable liver stiffness measurements in patients with an invalid TE examination. We reviewed 1975 patients with 5764 TE exams performed between 2007 and 2014, to identify failures and unreliable exams. Fifty-four patients with an invalid TE at their latest appointment entered a comparative feasibility study of TE vs. 2D-SWE. The initial TE exam was successful in 93% (1835/1975) of patients. Success rate increased from 89% to 96% when the XL probe became available (OR: 1.07, 95% CI 1.06-1.09). Likewise, re-examining those with a failed or unreliable TE led to a reliable TE in 96% of patients. Combining availability of the XL probe with TE re-examination resulted in a 99.5% success rate on a per-patient level. When comparing the feasibility of TE vs. 2D-SWE, 96% (52/54) of patients obtained a reliable TE, while 2D-SWE was reliable in 63% (34/54, p < 0.001). The odds of a successful 2D-SWE exam decreased with higher skin-capsule distance (OR = 0.77, 95% CI 0.67-0.98). Transient elastography can be accomplished in nearly all patients by use of the FibroScan XL probe and repeated examinations. In difficult-to-scan patients, the feasibility of TE is superior to 2D-SWE.

Shear-wave elastographic features of breast cancers: comparison with mechanical elasticity and histopathologic characteristics.

PubMed

Lee, Su Hyun; Moon, Woo Kyung; Cho, Nariya; Chang, Jung Min; Moon, Hyeong-Gon; Han, Wonshik; Noh, Dong-Young; Lee, Jung Chan; Kim, Hee Chan; Lee, Kyoung-Bun; Park, In-Ae

2014-03-01

The objective of this study was to compare the quantitative and qualitative shear-wave elastographic (SWE) features of breast cancers with mechanical elasticity and histopathologic characteristics. This prospective study was conducted with institutional review board approval, and written informed consent was obtained. Shear-wave elastography was performed for 30 invasive breast cancers in 30 women before surgery. The mechanical elasticity of a fresh breast tissue section, correlated with the ultrasound image, was measured using an indentation system. Quantitative (maximum, mean, minimum, and standard deviation of elasticity in kilopascals) and qualitative (color heterogeneity and presence of signal void areas in the mass) SWE features were compared with mechanical elasticity and histopathologic characteristics using the Pearson correlation coefficient and the Wilcoxon signed rank test. Maximum SWE values showed a moderate correlation with maximum mechanical elasticity (r = 0.530, P = 0.003). There were no significant differences between SWE values and mechanical elasticity in histologic grade I or II cancers (P = 0.268). However, SWE values were significantly higher than mechanical elasticity in histologic grade III cancers (P < 0.001), which have low amounts of fibrosis, high tumor cellularity, and intratumoral necrosis. In addition, color heterogeneity was correlated with intratumoral heterogeneity of mechanical elasticity (r = 0.469, P = 0.009). Signal void areas in the masses were present in 43% of breast cancers (13 of 30) and were correlated with dense collagen depositions (n = 11) or intratumoral necrosis (n = 2). Quantitative and qualitative SWE features reflect both the mechanical elasticity and histopathologic characteristics of breast cancers.

Shear-Wave Elastography for the Estimation of Liver Fibrosis in Chronic Liver Disease: Determining Accuracy and Ideal Site for Measurement

PubMed Central

Dhyani, Manish; Vij, Abhinav; Bhan, Atul K.; Halpern, Elkan F.; Méndez-Navarro, Jorge; Corey, Kathleen E.; Chung, Raymond T.

2015-01-01

Purpose To evaluate the accuracy of shear-wave elastography (SWE) for staging liver fibrosis in patients with diffuse liver disease (including patients with hepatitis C virus [HCV]) and to determine the relative accuracy of SWE measurements obtained from different hepatic acquisition sites for staging liver fibrosis. Materials and Methods The institutional review board approved this single-institution prospective study, which was performed between January 2010 and March 2013 in 136 consecutive patients who underwent SWE before their scheduled liver biopsy (age range, 18–76 years; mean age, 49 years; 70 men, 66 women). Informed consent was obtained from all patients. SWE measurements were obtained at four sites in the liver. Biopsy specimens were reviewed in a blinded manner by a pathologist using METAVIR criteria. SWE measurements and biopsy results were compared by using the Spearman correlation and receiver operating characteristic (ROC) curve analysis. Results SWE values obtained at the upper right lobe showed the highest correlation with estimation of fibrosis (r = 0.41, P < .001). Inflammation and steatosis did not show any correlation with SWE values except for values from the left lobe, which showed correlation with steatosis (r = 0.24, P = .004). The area under the ROC curve (AUC) in the differentiation of stage F2 fibrosis or greater, stage F3 fibrosis or greater, and stage F4 fibrosis was 0.77 (95% confidence interval [CI]: 0.68, 0.86), 0.82 (95% CI: 0.75, 0.91), and 0.82 (95% CI: 0.70, 0.95), respectively, for all subjects who underwent liver biopsy. The corresponding AUCs for the subset of patients with HCV were 0.80 (95% CI: 0.67, 0.92), 0.82 (95% CI: 0.70, 0.95), and 0.89 (95% CI: 0.73, 1.00). The adjusted AUCs for differentiating stage F2 or greater fibrosis in patients with chronic liver disease and those with HCV were 0.84 and 0.87, respectively. Conclusion SWE estimates of liver stiffness obtained from the right upper lobe showed the best correlation with liver fibrosis severity and can potentially be used as a noninvasive test to differentiate intermediate degrees of liver fibrosis in patients with liver disease. © RSNA, 2014 Online supplemental material is available for this article. PMID:25393946

Replacement of SSE with NASA's POWER Project GIS-enabled Web Data Portal

Atmospheric Science Data Center

2018-04-30

Replacement of SSE with NASA's POWER Project GIS-enabled Web Data Portal Friday, March ... 2018 Replacement of SSE (Release 6) with NASA's Prediction of Worldwide Energy Resource (POWER) Project GIS-enabled Web ... Worldwide Energy Resource (POWER) Project funded largely by NASA Earth Applied Sciences program.   The new POWER web portal ...

Non-invasive evaluation of stable renal allograft function using point shear-wave elastography.

PubMed

Kim, Bom Jun; Kim, Chan Kyo; Park, Jung Jae

2018-01-01

To investigate the feasibility of point shear-wave elastography (SWE) in evaluating patients with stable renal allograft function who underwent protocol biopsies. 95 patients with stable renal allograft function that underwent ultrasound-guided biopsies at predefined time points (10 days or 1 year after transplantation) were enrolled. Ultrasound and point SWE examinations were performed immediately before protocol biopsies. Patients were categorized into two groups: subclinical rejection (SCR) and non-SCR. Tissue elasticity (kPa) on SWE was measured in the cortex of all renal allografts. SCR was pathologically confirmed in 34 patients. Tissue elasticity of the SCR group (31.0 kPa) was significantly greater than that of the non-SCR group (24.5 kPa) (=0.016), while resistive index value did not show a significant difference between the two groups (p = 0.112). Tissue elasticity in renal allografts demonstrated significantly moderate negative correlation with estimated glomerular filtration rate (correlation coefficient = -0.604, p < 0.001). Tissue elasticity was not independent factor for SCR prediction on multivariate analysis. As a non-invasive tool, point SWE appears feasible in distinguishing between patients with SCR and without SCR in stable functioning renal allografts. Moreover, it may demonstrate the functional state of renal allografts. Advances in knowledge: On point SWE, SCR has greater tissue elasticity than non-SCR.

Spatial and temporal snowpack variation in the crown of the continent ecosystem

USGS Publications Warehouse

Selkowitz, D.J.; Fagre, D.B.; Reardon, B.A.

2002-01-01

Snowpack related ecosystem changes such as glacier recession and alpine treeline advance have been documented in the Crown of the Continent Ecosystem (CCE) over the course of the previous 150 years. Using data from the Natural Resource Conservation Service's SNOTEL sites and snow course surveys, we examined the spatial and temporal variation in snowpack in the region. SNOTEL data suggest CCE snowpacks are larger and more persistent than in most regions of the Western U.S., and that water year precipitation, rather than mean temperature, is the primary control on April 1 snow water equivalent (SWE). Snow course data indicate a statistically significant downward trend in mean April 1 SWE for the period 1950-2001 but no statistically significant trend in mean May 1 SWE for the longer period 1922-2001. Further analysis reveals that variations in both April 1 and May 1 mean SWE are closely tied to the Pacific Decadal Oscillation, an ENSO-like interdecadal pattern of Pacific Ocean climate variability. Despite no significant trend in mean May 1 SWE between 1922-2001, glaciers in Glacier National Park receded steadily during this period, implying changing climatic conditions crossed a threshold for glacier mass balance maintenace sometime between the Little Ice Age glacial maxima and 1922.

The value of shear wave elastography in the quantification of corpus cavernosum penis rigidity and its alteration with age.

PubMed

Inci, Ercan; Turkay, Rustu; Nalbant, Mustafa Orhan; Yenice, Mustafa Gurkan; Tugcu, Volkan

2017-04-01

The goal of this study was to measure corpus cavernosum (CC) penis rigidity with shear wave elastography (SWE) in healthy volunteers and to evaluate the change of rigidity with age. SWE was performed in 60 healthy volunteers (age range 20-71, mean 47±12,83 years). Volunteers were divided into 2 groups by age (Group 1 age <50, group 2 age ≥50). We assessed SWE in 3 parts of penis (proximal, middle and glans penis) on both sides of CC. All values of SWE (in kilo Pascal) were noted along with volunteers' ages. The measurements were done both with transverse (T) and longitudinal (L) sections. We compared all SW values of penis parts and their alterations with age. The shear wave elastography values of CC penis increased with increasing age (p<0,01). There was no significant difference between both sides of CC penis (p<0,05). We calculated no significant difference between T and L sections of all parts of penis (p<0,05). SWE can provide noninvasive quantitative data of CC penis rigidity and its alteration with age. These data may create a new approach in the evaluation process and treatment options for penile pathologies. Copyright © 2017 Elsevier B.V. All rights reserved.

Validation of Shear Wave Elastography Cutoff Values on the Supersonic Aixplorer for Practical Clinical Use in Liver Fibrosis Staging.

PubMed

Dhyani, Manish; Grajo, Joseph R; Bhan, Atul K; Corey, Kathleen; Chung, Raymond; Samir, Anthony E

2017-06-01

The purpose of this study was to determine the validity of previously established ultrasound shear wave elastography (SWE) cut-off values (≥F2 fibrosis) on an independent cohort of patients with chronic liver disease. In this cross-sectional study, approved by the institutional review board and compliant with the Health Insurance Portability and Accountability Act, 338 patients undergoing liver biopsy underwent SWE using an Aixplorer ultrasound machine (SuperSonic Imagine, Aix-en-Provence, France). Median SWE values were calculated from sets of 10 elastograms. A single blinded pathologist evaluated METAVIR fibrosis staging as the gold standard. The study analyzed 277 patients with a mean age of 48 y. On pathologic examination, 212 patients (76.5%) had F0-F1 fibrosis, whereas 65 (23.5%) had ≥F2 fibrosis. Spearman's correlation of fibrosis with SWE was 0.456 (p < 0.001). A cut-off value of 7.29 kPa yielded sensitivity of 95.4% and specificity of 50.5% for the diagnosis of METAVIR stage ≥F2 liver fibrosis in patients with liver disease using the SuperSonic Imagine Aixplorer SWE system. Copyright © 2017 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Accuracy of Snow Water Equivalent Estimated From GPS Vertical Displacements: A Synthetic Loading Case Study for Western U.S. Mountains

NASA Astrophysics Data System (ADS)

Enzminger, Thomas L.; Small, Eric E.; Borsa, Adrian A.

2018-01-01

GPS monitoring of solid Earth deformation due to surface loading is an independent approach for estimating seasonal changes in terrestrial water storage (TWS). In western United States (WUSA) mountain ranges, snow water equivalent (SWE) is the dominant component of TWS and an essential water resource. While several studies have estimated SWE from GPS-measured vertical displacements, the error associated with this method remains poorly constrained. We examine the accuracy of SWE estimated from synthetic displacements at 1,395 continuous GPS station locations in the WUSA. Displacement at each station is calculated from the predicted elastic response to variations in SWE from SNODAS and soil moisture from the NLDAS-2 Noah model. We invert synthetic displacements for TWS, showing that both seasonal accumulation and melt as well as year-to-year fluctuations in peak SWE can be estimated from data recorded by the existing GPS network. Because we impose a smoothness constraint in the inversion, recovered TWS exhibits mass leakage from mountain ranges to surrounding areas. This leakage bias is removed via linear rescaling in which the magnitude of the gain factor depends on station distribution and TWS anomaly patterns. The synthetic GPS-derived estimates reproduce approximately half of the spatial variability (unbiased root mean square error ˜50%) of TWS loading within mountain ranges, a considerable improvement over GRACE. The inclusion of additional simulated GPS stations improves representation of spatial variations. GPS data can be used to estimate mountain-range-scale SWE, but effects of soil moisture and other TWS components must first be subtracted from the GPS-derived load estimates.

Full-length amyloid precursor protein regulates lipoprotein metabolism and amyloid-β clearance in human astrocytes.

PubMed

Fong, Lauren K; Yang, Max M; Dos Santos Chaves, Rodrigo; Reyna, Sol M; Langness, Vanessa F; Woodruff, Grace; Roberts, Elizabeth A; Young, Jessica E; Goldstein, Lawrence S B

2018-06-01

Mounting evidence suggests that alterations in cholesterol homeostasis are involved in Alzheimer's disease (AD) pathogenesis. Amyloid precursor protein (APP) or multiple fragments generated by proteolytic processing of APP have previously been implicated in the regulation of cholesterol metabolism. However, the physiological function of APP in regulating lipoprotein homeostasis in astrocytes, which are responsible for de novo cholesterol biosynthesis and regulation in the brain, remains unclear. To address this, here we used CRISPR/Cas9 genome editing to generate isogenic APP-knockout (KO) human induced pluripotent stem cells (hiPSCs) and differentiated them into human astrocytes. We found that APP-KO astrocytes have reduced cholesterol and elevated levels of sterol regulatory element-binding protein (SREBP) target gene transcripts and proteins, which were both downstream consequences of reduced lipoprotein endocytosis. To elucidate which APP fragments regulate cholesterol homeostasis and examine whether familial AD mutations in APP affect lipoprotein metabolism, we analyzed an isogenic allelic series harboring the APP Swedish and APP V717F variants. Only astrocytes homozygous for the APP Swedish (APP Swe/Swe ) mutation, which had reduced full-length APP (FL APP) due to increased β-secretase cleavage, recapitulated the APP-KO phenotypes. Astrocytic internalization of amyloid-β (Aβ), another ligand for low-density lipoprotein (LDL) receptors, was also impaired in APP-KO and APP Swe/Swe astrocytes. Finally, impairing cleavage of FL APP through β-secretase inhibition in APP Swe/Swe astrocytes reversed the LDL and Aβ endocytosis defects. In conclusion, FL APP is involved in the endocytosis of LDL receptor ligands and required for proper cholesterol homeostasis and Aβ clearance in human astrocytes. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

Validating SWE reconstruction using Airborne Snow Observatory measurements in the Sierra Nevada

NASA Astrophysics Data System (ADS)

Bair, N.; Rittger, K.; Davis, R. E.; Dozier, J.

2015-12-01

The Airborne Snow Observatory (ASO) program offers high resolution estimates of snow water equivalent (SWE) in several small basins across California during the melt season. Primarily, water managers use this information to model snowmelt runoff into reservoirs. Another, and potentially more impactful, use of ASO SWE measurements is in validating and improving satellite-based SWE estimates which can be used in austere regions with no ground-based snow or water measurements, such as Afghanistan's Hindu Kush. Using the entire ASO dataset to date (2013-2015) which is mostly from the Upper Tuolumne basin, but also includes measurements from 2015 in the Kings, Rush Creek, Merced, and Mammoth Lakes basins, we compare ASO measurements to those from a SWE reconstruction method. Briefly, SWE reconstruction involves downscaling energy balance forcings to compute potential melt energy, then using satellite-derived estimates of fractional snow covered area (fSCA) to estimate snow melt from potential melt. The snowpack can then be built in reverse, given a remotely-sensed date of snow disappearance (fSCA=0). Our model has improvements over previous iterations in that it: uses the full energy balance (compared to a modified degree-day) approach, models bulk and surface snow temperatures, accounts for ephemeral snow, and uses a remotely-sensed snow albedo adjusted for impurities. To check that ASO provides accurate snow measurements, we compare fSCA derived from ASO snow depth at 3 m resolution with fSCA from a spectral unmixing algorithm for LandSAT at 30 m, and from binary SCA estimates from Geoeye at 0.5 m from supervised classification. To conclude, we document how our reconstruction model has evolved over the years and provide specific examples where improvements have been made using ASO and other verification sources.

Assessment of biopsy‐proven liver fibrosis by two‐dimensional shear wave elastography: An individual patient data‐based meta‐analysis

PubMed Central

de Lédinghen, Victor; Cassinotto, Christophe; Chu, Winnie C.‐W.; Leung, Vivian Y.‐F.; Ferraioli, Giovanna; Filice, Carlo; Castera, Laurent; Vilgrain, Valérie; Ronot, Maxime; Dumortier, Jérôme; Guibal, Aymeric; Pol, Stanislas; Trebicka, Jonel; Jansen, Christian; Strassburg, Christian; Zheng, Rongqin; Zheng, Jian; Francque, Sven; Vanwolleghem, Thomas; Vonghia, Luisa; Manesis, Emanuel K.; Zoumpoulis, Pavlos; Sporea, Ioan; Thiele, Maja; Krag, Aleksander; Cohen‐Bacrie, Claude; Criton, Aline; Gay, Joel; Deffieux, Thomas; Friedrich‐Rust, Mireen

2017-01-01

Two‐dimensional shear wave elastography (2D‐SWE) has proven to be efficient for the evaluation of liver fibrosis in small to moderate‐sized clinical trials. We aimed at running a larger‐scale meta‐analysis of individual data. Centers which have worked with Aixplorer ultrasound equipment were contacted to share their data. Retrospective statistical analysis used direct and paired receiver operating characteristic and area under the receiver operating characteristic curve (AUROC) analyses, accounting for random effects. Data on both 2D‐SWE and liver biopsy were available for 1,134 patients from 13 sites, as well as on successful transient elastography in 665 patients. Most patients had chronic hepatitis C (n = 379), hepatitis B (n = 400), or nonalcoholic fatty liver disease (n = 156). AUROCs of 2D‐SWE in patients with hepatitis C, hepatitis B, and nonalcoholic fatty liver disease were 86.3%, 90.6%, and 85.5% for diagnosing significant fibrosis and 92.9%, 95.5%, and 91.7% for diagnosing cirrhosis, respectively. The AUROC of 2D‐SWE was 0.022‐0.084 (95% confidence interval) larger than the AUROC of transient elastography for diagnosing significant fibrosis (P = 0.001) and 0.003‐0.034 for diagnosing cirrhosis (P = 0.022) in all patients. This difference was strongest in hepatitis B patients. Conclusion: 2D‐SWE has good to excellent performance for the noninvasive staging of liver fibrosis in patients with hepatitis B; further prospective studies are needed for head‐to‐head comparison between 2D‐SWE and other imaging modalities to establish disease‐specific appropriate cutoff points for assessment of fibrosis stage. (Hepatology 2018;67:260‐272). PMID:28370257

Using machine learning to predict snow water equivalent in the Sierra Nevada USA and Afghanistan

NASA Astrophysics Data System (ADS)

Bair, N.; Rittger, K.; Dozier, J.

2017-12-01

In many mountain regions, snowmelt provides most of the runoff. Ranges such as the Sierra Nevada USA benefit from hundreds of manual and automated snow measurement stations as well as basin-wide snow water equavalent (SWE) estimates from new platforms like the Airborne Snow Observatory. Thus, we have been able to use the Sierra Nevada as a testbed to validate an approach called SWE reconstruction, where the snowpack is built-up in reverse using downscaled energy balance forcings. Our past work has shown that SWE reconstruction produces some of the most accurate basin-wide SWE estimates, comparable in accuracy to a snow pillow/course interpolation, but requires no in situ measurements, which is its main advantage. The disadvantages are that reconstruction cannot be used for a forecast and is only valid during the ablation period. To address these shortcomings, we have used machine learning trained on reconstructed SWE in the Sierra Nevada and Afghanistan, where there are no accessible snowpack measurements. Predictors are physiographic and remotely-sensed variables, including brightness temperatures from a new enhanced resolution passive microwave dataset. Two machine learning techniques—bagged regression trees and feed-forward neural networks—were used. Results show little bias on average and < 100 mm RMSE. For both areas, daily SWE climatology and fractional snow-covered area were the most important predictors. As expected, the passive microwave brigthness temperatures showed some predictive power in Afghanistan, with its almost nonexistent tree cover, but no predictive power in the Sierra Nevada, with its extensive canopy-covered snowpack. In the Sierra, we also explored how our machine learning approach performed outside of the training period, i.e. the ablation period.

Clinical application of qualitative assessment for breast masses in shear-wave elastography.

PubMed

Gweon, Hye Mi; Youk, Ji Hyun; Son, Eun Ju; Kim, Jeong-Ah

2013-11-01

To evaluate the interobserver agreement and the diagnostic performance of various qualitative features in shear-wave elastography (SWE) for breast masses. A total of 153 breast lesions in 152 women who underwent B-mode ultrasound and SWE before biopsy were included. Qualitative analysis in SWE was performed using two different classifications: E values (Ecol; 6-point color score, Ehomo; homogeneity score and Esha; shape score) and a four-color pattern classification. Two radiologists reviewed five data sets: B-mode ultrasound, SWE, and combination of both for E values and four-color pattern. The BI-RADS categories were assessed B-mode and combined sets. Interobserver agreement was assessed using weighted κ statistics. Areas under the receiver operating characteristic curve (AUC), sensitivity, and specificity were analyzed. Interobserver agreement was substantial for Ecol (κ=0.79), Ehomo (κ=0.77) and four-color pattern (κ=0.64), and moderate for Esha (κ=0.56). Better-performing qualitative features were Ecol and four-color pattern (AUCs, 0.932 and 0.925) compared with Ehomo and Esha (AUCs, 0.857 and 0.864; P<0.05). The diagnostic performance of B-mode ultrasound (AUC, 0.950) was not significantly different from combined sets with E value and with four color pattern (AUCs, 0.962 and 0.954). When all qualitative values were negative, leading to downgrade the BI-RADS category, the specificity increased significantly from 16.5% to 56.1% (E value) and 57.0% (four-color pattern) (P<0.001) without improvement in sensitivity. The qualitative SWE features were highly reproducible and showed good diagnostic performance in suspicious breast masses. Adding qualitative SWE to B-mode ultrasound increased specificity in decision making for biopsy recommendation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Variability common to first leaf dates and snowpack in the western conterminous United States

USGS Publications Warehouse

McCabe, Gregory J.; Betancourt, Julio L.; Pederson, Gregory T.; Schwartz, Mark D.

2013-01-01

Singular value decomposition is used to identify the common variability in first leaf dates (FLDs) and 1 April snow water equivalent (SWE) for the western United States during the period 1900–2012. Results indicate two modes of joint variability that explain 57% of the variability in FLD and 69% of the variability in SWE. The first mode of joint variability is related to widespread late winter–spring warming or cooling across the entire west. The second mode can be described as a north–south dipole in temperature for FLD, as well as in cool season temperature and precipitation for SWE, that is closely correlated to the El Niño–Southern Oscillation. Additionally, both modes of variability indicate a relation with the Pacific–North American atmospheric pattern. These results indicate that there is a substantial amount of common variance in FLD and SWE that is related to large-scale modes of climate variability.

Coupling the snow thermodynamic model SNOWPACK with the microwave emission model of layered snowpacks for subarctic and arctic snow water equivalent retrievals

NASA Astrophysics Data System (ADS)

Langlois, A.; Royer, A.; Derksen, C.; Montpetit, B.; Dupont, F.; GoïTa, K.

2012-12-01

Satellite-passive microwave remote sensing has been extensively used to estimate snow water equivalent (SWE) in northern regions. Although passive microwave sensors operate independent of solar illumination and the lower frequencies are independent of atmospheric conditions, the coarse spatial resolution introduces uncertainties to SWE retrievals due to the surface heterogeneity within individual pixels. In this article, we investigate the coupling of a thermodynamic multilayered snow model with a passive microwave emission model. Results show that the snow model itself provides poor SWE simulations when compared to field measurements from two major field campaigns. Coupling the snow and microwave emission models with successive iterations to correct the influence of snow grain size and density significantly improves SWE simulations. This method was further validated using an additional independent data set, which also showed significant improvement using the two-step iteration method compared to standalone simulations with the snow model.

Towards a conceptual framework of OSH risk management in smart working environments based on smart PPE, ambient intelligence and the Internet of Things technologies.

PubMed

Podgórski, Daniel; Majchrzycka, Katarzyna; Dąbrowska, Anna; Gralewicz, Grzegorz; Okrasa, Małgorzata

2017-03-01

Recent developments in domains of ambient intelligence (AmI), Internet of Things, cyber-physical systems (CPS), ubiquitous/pervasive computing, etc., have led to numerous attempts to apply ICT solutions in the occupational safety and health (OSH) area. A literature review reveals a wide range of examples of smart materials, smart personal protective equipment and other AmI applications that have been developed to improve workers' safety and health. Because the use of these solutions modifies work methods, increases complexity of production processes and introduces high dynamism into thus created smart working environments (SWE), a new conceptual framework for dynamic OSH management in SWE is called for. A proposed framework is based on a new paradigm of OSH risk management consisting of real-time risk assessment and the capacity to monitor the risk level of each worker individually. A rationale for context-based reasoning in SWE and a respective model of the SWE-dedicated CPS are also proposed.

Uncertainty in the Future of Seasonal Snowpack over North America.

NASA Astrophysics Data System (ADS)

McCrary, R. R.; Mearns, L.

2017-12-01

The uncertainty in future changes in seasonal snowpack (snow water equivalent, SWE) and snow cover extent (SCE) for North America are explored using the North American Regional Climate Change Assessment Program (NARCCAP) suite of regional climate models (RCMs) and their driving CMIP3 global circulation models (GCMs). The higher resolution of the NARCCAP RCMs is found to add significant value to the details of future projections of SWE in topographically complex regions such as the Pacific Northwest and the Rocky Mountains. The NARCCAP models also add detailed information regarding changes in the southernmost extent of snow cover. 11 of the 12 NARCCAP ensemble members contributed SWE output which we use to explore the uncertainty in future snowpack at higher resolution. In this study, we quantify the uncertainty in future projections by looking at the spread of the interquartile range of the different models. By mid-Century the RCMs consistently predict that winter SWE amounts will decrease over most of North America. The only exception to this is in Northern Canada, where increased moisture supply leads to increases in SWE in all but one of the RCMs. While the models generally agree on the sign of the change in SWE, there is considerable spread in the magnitude (absolute and percent) of the change. The RCMs also agree that the number of days with measureable snow on the ground is projected to decrease, with snow accumulation occurring later in the Fall/Winter and melting starting earlier in the Spring/Summer. As with SWE amount, spread across the models is large for changes in the timing of the snow season and can vary by over a month between models. While most of the NARCCAP models project a total loss of measurable snow along the southernmost edge of their historical range, there is considerable uncertainty about where this will occur within the ensemble due to the bias in snow cover extent in the historical simulations. We explore methods to increase our confidence about the regions that will lose any seasonal snow.

Impacts of Aerosols on Seasonal Precipitation and Snowpack in California Based on Convection-Permitting WRF-Chem Simulations

NASA Astrophysics Data System (ADS)

Gu, Y.; Wu, L.; Jiang, J. H.; Su, H.; Yu, N.; Zhao, C.; Qian, Y.; Zhao, B.; Liou, K. N.; Choi, Y. S.

2017-12-01

A version of the WRF-Chem model with fully coupled aerosol-meteorology-snowpack is employed to investigate the impacts of various aerosol sources on precipitation and snowpack in California. In particular, the impacts of locally emitted anthropogenic and dust aerosols, and aerosols transported from outside of California are studied. We differentiate three pathways of aerosol effects including aerosol-radiation interaction (ARI), aerosol-snow interaction (ASI), and aerosol-cloud interaction (ACI). The convection-permitting model simulations show that precipitation, snow water equivalent (SWE), and surface air temperature averaged over the whole domain (34-42°N, 117-124°W, not including ocean points) are reduced when aerosols are included, therefore reducing the high model biases of these variables when aerosol effects are not considered. Aerosols affect California water resources through the warming of mountain tops and anomalously low precipitation, however, different aerosol sources play different roles in changing surface temperature, precipitation and snowpack in California by means of various weights of the three pathways. ARI by all aerosols mainly cools the surface, leading to slightly increased SWE over the mountains. Locally emitted dust aerosols warm the surface of mountain tops through ASI, in which the reduced snow albedo associated with dirty snow leads to more surface absorption of solar radiation and reduced SWE. Transported and local anthropogenic aerosols play a dominant role in increasing cloud water amount but reducing precipitation through ACI, leading to reduced SWE and runoff over the Sierra Nevada, as well as the warming of mountain tops associated with decreased SWE and hence lower surface albedo. The average changes in surface temperature from October to June are about -0.19 K and 0.22 K for the whole domain and over mountain tops, respectively. Overall, the averaged reduction during October to June is about 7% for precipitation, 3% for SWE, and 7% for surface runoff for the whole domain, while the corresponding numbers are 12%, 10%, and 10% for mountain tops. The reduction in SWE is more significant in a dry year, with 9% for the whole domain and 16% for mountain tops.

Impact of spatial variation in snow water equivalent and snow ablation on spring snowcover depletion over an alpine ridge

NASA Astrophysics Data System (ADS)

Schirmer, Michael; Harder, Phillip; Pomeroy, John

2016-04-01

The spatial and temporal dynamics of mountain snowmelt are controlled by the spatial distribution of snow accumulation and redistribution and the pattern of melt energy applied to this snowcover. In order to better quantify the spatial variations of accumulation and ablation, Structure-from-Motion techniques were applied to sequential aerial photographs of an alpine ridge in the Canadian Rocky Mountains taken from an Unmanned Aerial Vehicle (UAV). Seven spatial maps of snow depth and changes to depth during late melt (May-July) were generated at very high resolutions covering an area of 800 x 600 m. The accuracy was assessed with over 100 GPS measurements and RMSE were found to be less than 10 cm. Low resolution manual measurements of density permitted calculation of snow water equivalent (SWE) and change in SWE (ablation rate). The results indicate a highly variable initial SWE distribution, which was five times more variable than the spatial variation in ablation rate. Spatial variation in ablation rate was still substantial, with a factor of two difference between north and south aspects and small scale variations due to local dust deposition. However, the impact of spatial variations in ablation rate on the snowcover depletion curve could not be discerned. The reason for this is that only a weak spatial correlation developed between SWE and ablation rate. These findings suggest that despite substantial variations in ablation rate, snowcover depletion curve calculations should emphasize the spatial variation of initial SWE rather than the variation in ablation rate. While there is scientific evidence from other field studies that support this, there are also studies that suggest that spatial variations in ablation rate can influence snowcover depletion curves in complex terrain, particularly in early melt. The development of UAV photogrammetry has provided an opportunity for further detailed measurement of ablation rates, SWE and snowcover depletion over complex terrain and UAV field studies are recommended to clarify the relative importance of SWE and melt variability on snowcover depletion in various environmental conditions.

Liver fibrosis staging with a new 2D-shear wave elastography using comb-push technique: Applicability, reproducibility, and diagnostic performance

PubMed Central

Lee, Sang Min; Kang, Hyo-Jin; Yang, Hyung Kung; Yoon, Jeong Hee; Chang, Won; An, Su Joa; Lee, Kyoung Bun; Baek, Seung Yon

2017-01-01

Objective To evaluate the applicability, reproducibility, and diagnostic performance of a new 2D-shear wave elastography (SWE) using the comb-push technique (2D CP-SWE) for detection of hepatic fibrosis, using histopathology as the reference standard. Materials and methods This prospective study was approved by the institutional review board, and informed consent was obtained from all patients. The liver stiffness (LS) measurements were obtained from 140 patients, using the new 2D-SWE, which uses comb-push excitation to produce shear waves and a time-aligned sequential tracking method to detect shear wave signals. The applicability rate of 2D CP-SWE was estimated, and factors associated with its applicability were identified. Intraobserver reproducibility was evaluated in the 105 patients with histopathologic diagnosis, and interobserver reproducibility was assessed in 20 patients. Diagnostic performance of the 2D CP-SWE for hepatic fibrosis was evaluated by receiver operating characteristic (ROC) curve analysis. Results The applicability rate of 2D CP-SWE was 90.8% (109 of 120). There was a significant difference in age, presence or absence of ascites, and the distance from the transducer to the Glisson capsule between the patients with applicable LS measurements and patients with unreliable measurement or technical failure. The intraclass correlation of interobserver agreement was 0.87, and the value for the intraobserver agreement was 0.95. The area under the ROC curve of LS values for stage F2 fibrosis or greater, stage F3 or greater, and stage F4 fibrosis was 0.874 (95% confidence interval [CI]: 0.794–0.930), 0.905 (95% CI: 0.832–0.954), and 0.894 (95% CI: 0.819–0.946), respectively. Conclusion 2D CP-SWE can be employed as a reliable method for assessing hepatic fibrosis with a reasonably good diagnostic performance, and its applicability might be influenced by age, ascites, and the distance between the transducer and Glisson capsule. PMID:28510583

Impacts of aerosols on seasonal precipitation and snowpack in California based on convection-permitting WRF-Chem simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Longtao; Gu, Yu; Jiang, Jonathan H.

Here, a version of the WRF-Chem model with fully coupled aerosol–meteorology–snowpack is employed to investigate the impacts of various aerosol sources on precipitation and snowpack in California. In particular, the impacts of locally emitted anthropogenic and dust aerosols, and aerosols transported from outside California are studied. We differentiate three pathways of aerosol effects: aerosol–radiation interaction (ARI), aerosol–snow interaction (ASI), and aerosol–cloud interaction (ACI). The convection-permitting model simulations show that precipitation, snow water equivalent (SWE), and surface air temperature averaged over the whole domain (34–42° N, 117–124° W, not including ocean points) are reduced when aerosols are included, therefore reducing largemore » biases in these variables due to the absence of aerosol effects in the model. Aerosols affect California water resources through the warming of mountaintops and the reduction of precipitation; however, different aerosol sources play different roles in changing surface temperature, precipitation, and snowpack in California by means of various weights of the three pathways. ARI by all aerosols mainly cools the surface, leading to slightly increased SWE over the mountains. Locally emitted dust aerosols warm the surface of mountaintops through ASI, in which the reduced snow albedo associated with dusty snow leads to more surface absorption of solar radiation and reduced SWE. Transported aerosols and local anthropogenic aerosols play a dominant role in increasing nonprecipitating clouds but reducing precipitation through ACI, leading to reduced SWE and runoff on the Sierra Nevada, as well as the warming of mountaintops associated with decreased SWE and hence lower surface albedo. The average changes in surface temperature from October 2012 to June 2013 are about –0.19 and 0.22 K for the whole domain and over mountaintops, respectively. Overall, the averaged reduction during October to June is about 7 % for precipitation, 3 % for SWE, and 7 % for surface runoff for the whole domain, while the corresponding numbers are 12, 10, and 10 % for the mountaintops. The reduction in SWE is more significant in a dry year, with 9 % for the whole domain and 16 % for the mountaintops. The maximum reduction of ~20 % in precipitation occurs in May and is associated with the maximum aerosol loading, leading to the largest decrease in SWE and surface runoff over that period. It is also found that dust aerosols can cause early snowmelt on the mountaintops and reduced surface runoff after April.« less

Impacts of aerosols on seasonal precipitation and snowpack in California based on convection-permitting WRF-Chem simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Longtao; Gu, Yu; Jiang, Jonathan H.

A version of the WRF-Chem model with fully coupled aerosol–meteorology–snowpack is employed to investigate the impacts of various aerosol sources on precipitation and snowpack in California. In particular, the impacts of locally emitted anthropogenic and dust aerosols, and aerosols transported from outside California are studied. We differentiate three pathways of aerosol effects: aerosol–radiation interaction (ARI), aerosol–snow interaction (ASI), and aerosol–cloud interaction (ACI). The convection-permitting model simulations show that precipitation, snow water equivalent (SWE), and surface air temperature averaged over the whole domain (34–42° N, 117–124° W, not including ocean points) are reduced when aerosols are included, therefore reducing large biasesmore » in these variables due to the absence of aerosol effects in the model. Aerosols affect California water resources through the warming of mountaintops and the reduction of precipitation; however, different aerosol sources play different roles in changing surface temperature, precipitation, and snowpack in California by means of various weights of the three pathways. ARI by all aerosols mainly cools the surface, leading to slightly increased SWE over the mountains. Locally emitted dust aerosols warm the surface of mountaintops through ASI, in which the reduced snow albedo associated with dusty snow leads to more surface absorption of solar radiation and reduced SWE. Transported aerosols and local anthropogenic aerosols play a dominant role in increasing nonprecipitating clouds but reducing precipitation through ACI, leading to reduced SWE and runoff on the Sierra Nevada, as well as the warming of mountaintops associated with decreased SWE and hence lower surface albedo. The average changes in surface temperature from October 2012 to June 2013 are about -0.19 and 0.22 K for the whole domain and over mountaintops, respectively. Overall, the averaged reduction during October to June is about 7% for precipitation, 3% for SWE, and 7% for surface runoff for the whole domain, while the corresponding numbers are 12, 10, and 10% for the mountaintops. The reduction in SWE is more significant in a dry year, with 9% for the whole domain and 16% for the mountaintops. The maximum reduction of -20% in precipitation occurs in May and is associated with the maximum aerosol loading, leading to the largest decrease in SWE and surface runoff over that period. It is also found that dust aerosols can cause early snowmelt on the mountaintops and reduced surface runoff after April.« less

Impacts of aerosols on seasonal precipitation and snowpack in California based on convection-permitting WRF-Chem simulations

NASA Astrophysics Data System (ADS)

Wu, Longtao; Gu, Yu; Jiang, Jonathan H.; Su, Hui; Yu, Nanpeng; Zhao, Chun; Qian, Yun; Zhao, Bin; Liou, Kuo-Nan; Choi, Yong-Sang

2018-04-01

A version of the WRF-Chem model with fully coupled aerosol-meteorology-snowpack is employed to investigate the impacts of various aerosol sources on precipitation and snowpack in California. In particular, the impacts of locally emitted anthropogenic and dust aerosols, and aerosols transported from outside California are studied. We differentiate three pathways of aerosol effects: aerosol-radiation interaction (ARI), aerosol-snow interaction (ASI), and aerosol-cloud interaction (ACI). The convection-permitting model simulations show that precipitation, snow water equivalent (SWE), and surface air temperature averaged over the whole domain (34-42° N, 117-124° W, not including ocean points) are reduced when aerosols are included, therefore reducing large biases in these variables due to the absence of aerosol effects in the model. Aerosols affect California water resources through the warming of mountaintops and the reduction of precipitation; however, different aerosol sources play different roles in changing surface temperature, precipitation, and snowpack in California by means of various weights of the three pathways. ARI by all aerosols mainly cools the surface, leading to slightly increased SWE over the mountains. Locally emitted dust aerosols warm the surface of mountaintops through ASI, in which the reduced snow albedo associated with dusty snow leads to more surface absorption of solar radiation and reduced SWE. Transported aerosols and local anthropogenic aerosols play a dominant role in increasing nonprecipitating clouds but reducing precipitation through ACI, leading to reduced SWE and runoff on the Sierra Nevada, as well as the warming of mountaintops associated with decreased SWE and hence lower surface albedo. The average changes in surface temperature from October 2012 to June 2013 are about -0.19 and 0.22 K for the whole domain and over mountaintops, respectively. Overall, the averaged reduction during October to June is about 7 % for precipitation, 3 % for SWE, and 7 % for surface runoff for the whole domain, while the corresponding numbers are 12, 10, and 10 % for the mountaintops. The reduction in SWE is more significant in a dry year, with 9 % for the whole domain and 16 % for the mountaintops. The maximum reduction of ˜ 20 % in precipitation occurs in May and is associated with the maximum aerosol loading, leading to the largest decrease in SWE and surface runoff over that period. It is also found that dust aerosols can cause early snowmelt on the mountaintops and reduced surface runoff after April.

Impacts of aerosols on seasonal precipitation and snowpack in California based on convection-permitting WRF-Chem simulations

DOE PAGES

Wu, Longtao; Gu, Yu; Jiang, Jonathan H.; ...

2018-04-23

Here, a version of the WRF-Chem model with fully coupled aerosol–meteorology–snowpack is employed to investigate the impacts of various aerosol sources on precipitation and snowpack in California. In particular, the impacts of locally emitted anthropogenic and dust aerosols, and aerosols transported from outside California are studied. We differentiate three pathways of aerosol effects: aerosol–radiation interaction (ARI), aerosol–snow interaction (ASI), and aerosol–cloud interaction (ACI). The convection-permitting model simulations show that precipitation, snow water equivalent (SWE), and surface air temperature averaged over the whole domain (34–42° N, 117–124° W, not including ocean points) are reduced when aerosols are included, therefore reducing largemore » biases in these variables due to the absence of aerosol effects in the model. Aerosols affect California water resources through the warming of mountaintops and the reduction of precipitation; however, different aerosol sources play different roles in changing surface temperature, precipitation, and snowpack in California by means of various weights of the three pathways. ARI by all aerosols mainly cools the surface, leading to slightly increased SWE over the mountains. Locally emitted dust aerosols warm the surface of mountaintops through ASI, in which the reduced snow albedo associated with dusty snow leads to more surface absorption of solar radiation and reduced SWE. Transported aerosols and local anthropogenic aerosols play a dominant role in increasing nonprecipitating clouds but reducing precipitation through ACI, leading to reduced SWE and runoff on the Sierra Nevada, as well as the warming of mountaintops associated with decreased SWE and hence lower surface albedo. The average changes in surface temperature from October 2012 to June 2013 are about –0.19 and 0.22 K for the whole domain and over mountaintops, respectively. Overall, the averaged reduction during October to June is about 7 % for precipitation, 3 % for SWE, and 7 % for surface runoff for the whole domain, while the corresponding numbers are 12, 10, and 10 % for the mountaintops. The reduction in SWE is more significant in a dry year, with 9 % for the whole domain and 16 % for the mountaintops. The maximum reduction of ~20 % in precipitation occurs in May and is associated with the maximum aerosol loading, leading to the largest decrease in SWE and surface runoff over that period. It is also found that dust aerosols can cause early snowmelt on the mountaintops and reduced surface runoff after April.« less

Point shear wave elastography of the pancreas in patients with cystic fibrosis: a comparison with healthy controls.

PubMed

Pfahler, Matthias Hermann Christian; Kratzer, Wolfgang; Leichsenring, Michael; Graeter, Tilmann; Schmidt, Stefan Andreas; Wendlik, Inka; Lormes, Elisabeth; Schmidberger, Julian; Fabricius, Dorit

2018-02-19

Manifestations of cystic fibrosis in the pancreas are gaining in clinical importance as patients live longer. Conventional ultrasonography and point shear wave elastography (pSWE) imaging are non-invasive and readily available diagnostic methods that are easy to perform. The aim of this study was to perform conventional ultrasonography and obtain pSWE values in the pancreases of patients with cystic fibrosis and to compare the findings with those of healthy controls. 27 patients with cystic fibrosis (13 women/14 men; mean age 27.7 ± 13.7 years; range 9-58 years) and 60 healthy control subjects (30 women/30 men; mean age 30.3 ± 10.0 years; range 22-55 years) underwent examinations of the pancreas with conventional ultrasound and pSWE imaging. Patients with cystic fibrosis have an echogenic pancreatic parenchyma. We found cystic lesions of the pancreas in six patients. pSWE imaging of the pancreatic parenchyma gave significantly lower shear wave velocities in patients with cystic fibrosis than in the control group (1.01 m/s vs 1.30 m/s; p < 0.001). Using pSWE imaging in vivo, we have shown that the pancreas is considerably softer in patients with cystic fibrosis than in a healthy control population.

2D-Shear Wave Elastography in the Evaluation of Parathyroid Lesions in Patients with Hyperparathyroidism

PubMed Central

Golu, Ioana; Sporea, Ioan; Moleriu, Lavinia; Tudor, Anca; Cornianu, Marioara; Balas, Melania; Amzar, Daniela

2017-01-01

Background and Aims 2D-shear wave elastography (2D-SWE) is a relatively new elastographic technique. The aim of the present study is to determine the values of the elasticity indexes (EI) measured by 2D-SWE in parathyroid benign lesions (adenomas or hyperplasia) and to establish if this investigation is helpful for the preoperative identification of the parathyroid adenoma. Material and Methods The study groups were represented by 22 patients with primary or tertiary hyperparathyroidism, diagnosed by specific tests, and 43 healthy controls, in whom the thyroid parenchyma was evaluated, in order to compare the EI of the thyroid tissue with those of the parathyroid lesions. Results The mean EI measured by 2D-SWE in the parathyroid lesions was 10.2 ± 4.9 kPa, significantly lower than that of the normal thyroid parenchyma (19.5 ± 7.6 kPa; p = 0.007), indicating soft tissue. For a cutoff value of 12.5 kPa, the EI assessed by 2D-SWE had a sensitivity of 93% and a specificity of 86% (AUC = 0.949; p < 0.001) for predicting parathyroid lesions. Conclusion A value lower than 12.5 kPa for the mean EI measured by 2D-SWE can be used to confirm that the lesion/nodule is a parathyroid adenoma. PMID:28845158

Attribution of declining Western U.S. Snowpack to human effects

USGS Publications Warehouse

Pierce, D.W.; Barnett, T.P.; Hidalgo, H.G.; Das, T.; Bonfils, Celine; Santer, B.D.; Bala, G.; Dettinger, M.D.; Cayan, D.R.; Mirin, A.; Wood, A.W.; Nozawa, T.

2008-01-01

Observations show snowpack has declined across much of the western United States over the period 1950-99. This reduction has important social and economic implications, as water retained in the snowpack from winter storms forms an important part of the hydrological cycle and water supply in the region. A formal model-based detection and attribution (D-A) study of these reductions is performed. The detection variable is the ratio of 1 April snow water equivalent (SWE) to water-year-to-date precipitation (P), chosen to reduce the effect of P variability on the results. Estimates of natural internal climate variability are obtained from 1600 years of two control simulations performed with fully coupled ocean-atmosphere climate models. Estimates of the SWE/P response to anthropogenic greenhouse gases, ozone, and some aerosols are taken from multiple-member ensembles of perturbation experiments run with two models. The D-A shows the observations and anthropogenically forced models have greater SWE/P reductions than can be explained by natural internal climate variability alone. Model-estimated effects of changes in solar and volcanic forcing likewise do not explain the SWE/P reductions. The mean model estimate is that about half of the SWE/P reductions observed in the west from 1950 to 1999 are the result of climate changes forced by anthropogenic greenhouse gases, ozone, and aerosols. ?? 2008 American Meteorological Society.

Citizen Observatories: A Standards Based Architecture

NASA Astrophysics Data System (ADS)

Simonis, Ingo

2015-04-01

A number of large-scale research projects are currently under way exploring the various components of citizen observatories, e.g. CITI-SENSE (http://www.citi-sense.eu), Citclops (http://citclops.eu), COBWEB (http://cobwebproject.eu), OMNISCIENTIS (http://www.omniscientis.eu), and WeSenseIt (http://www.wesenseit.eu). Common to all projects is the motivation to develop a platform enabling effective participation by citizens in environmental projects, while considering important aspects such as security, privacy, long-term storage and availability, accessibility of raw and processed data and its proper integration into catalogues and international exchange and collaboration systems such as GEOSS or INSPIRE. This paper describes the software architecture implemented for setting up crowdsourcing campaigns using standardized components, interfaces, security features, and distribution capabilities. It illustrates the Citizen Observatory Toolkit, a software suite that allows defining crowdsourcing campaigns, to invite registered and unregistered participants to participate in crowdsourcing campaigns, and to analyze, process, and visualize raw and quality enhanced crowd sourcing data and derived products. The Citizen Observatory Toolkit is not a single software product. Instead, it is a framework of components that are built using internationally adopted standards wherever possible (e.g. OGC standards from Sensor Web Enablement, GeoPackage, and Web Mapping and Processing Services, as well as security and metadata/cataloguing standards), defines profiles of those standards where necessary (e.g. SWE O&M profile, SensorML profile), and implements design decisions based on the motivation to maximize interoperability and reusability of all components. The toolkit contains tools to set up, manage and maintain crowdsourcing campaigns, allows building on-demand apps optimized for the specific sampling focus, supports offline and online sampling modes using modern cell phones with built-in sensing technologies, automates the upload of the raw data, and handles conflation services to match quality requirements and analysis challenges. The strict implementation of all components using internationally adopted standards ensures maximal interoperability and reusability of all components. The Citizen Observatory Toolkit is currently developed as part of the COBWEB research project. COBWEB is partially funded by the European Programme FP7/2007-2013 under grant agreement n° 308513; part of the topic ENV.2012.6.5-1 "Developing community based environmental monitoring and information systems using innovative and novel earth observation applications.

Metabolic and Cardiovascular Response to Shallow Water Exercise in Young and Older Women.

ERIC Educational Resources Information Center

Campbell, Jennifer A.; D'Acquisto, Leo J.; D'Acquisto, Debra M.; Cline, Michael G.

2003-01-01

Compared the metabolic and cardiovascular responses of young and older women while performing shallow water exercise (SWE). Overall, SWE elicited metabolic and cardiovascular responses that met American College of Sports Medicine's guidelines for establishing health benefits. Older females self-selected a greater relative exercise intensity during…

Digitalk: Community, Convention, and Self-Expression

ERIC Educational Resources Information Center

Turner, Kristen Hawley

2011-01-01

Teens write all the time: They post messages to social networks; they chat via instant message (IM); they communicate by text. In all of these digital spaces, they write. However, the language that they use in these venues often does not follow the rules of standard written English (SWE). They experiment with language, manipulating SWE in ways…

Protective Nursing Advocacy: Translation and Psychometric Evaluation of an Instrument and a Descriptive Study of Swedish Registered Nurse Anesthetists' Beliefs and Actions.

PubMed

Sundqvist, Ann-Sofie; Anderzén-Carlsson, Agneta; Nilsson, Ulrica; Holmefur, Marie

2018-02-01

To translate and adapt the Protective Nursing Advocacy Scale (PNAS) into a Swedish version (PNAS-Swe), evaluate its psychometric properties, and describe registered nurse anesthetists' (RNAs) advocacy beliefs and actions from a protective perspective. A cross-sectional design was used. First, the PNAS was translated into Swedish. Next, the content and construct validity of the PNAS four subscales was evaluated. Finally, the PNAS-Swe was used to describe Swedish RNA beliefs and actions regarding protective nursing advocacy. The final PNAS-Swe has 29 items in four subscales. The RNAs reported that they feel that they should provide protective nursing advocacy for their patients. There were no differences in gender, or associations with age, or work experience regarding their advocacy beliefs or actions. The PNAS-Swe is valid for use in a Swedish context. Protective nursing advocacy is important to the RNAs, which is in congruence with earlier qualitative studies. Copyright © 2016 American Society of PeriAnesthesia Nurses. Published by Elsevier Inc. All rights reserved.

SwePep, a database designed for endogenous peptides and mass spectrometry.

PubMed

Fälth, Maria; Sköld, Karl; Norrman, Mathias; Svensson, Marcus; Fenyö, David; Andren, Per E

2006-06-01

A new database, SwePep, specifically designed for endogenous peptides, has been constructed to significantly speed up the identification process from complex tissue samples utilizing mass spectrometry. In the identification process the experimental peptide masses are compared with the peptide masses stored in the database both with and without possible post-translational modifications. This intermediate identification step is fast and singles out peptides that are potential endogenous peptides and can later be confirmed with tandem mass spectrometry data. Successful applications of this methodology are presented. The SwePep database is a relational database developed using MySql and Java. The database contains 4180 annotated endogenous peptides from different tissues originating from 394 different species as well as 50 novel peptides from brain tissue identified in our laboratory. Information about the peptides, including mass, isoelectric point, sequence, and precursor protein, is also stored in the database. This new approach holds great potential for removing the bottleneck that occurs during the identification process in the field of peptidomics. The SwePep database is available to the public.

Hydroquinone, a benzene metabolite, induces Hog1-dependent stress response signaling and causes aneuploidy in Saccharomyces cerevisiae.

PubMed

Shiga, Takeki; Suzuki, Hiroyuki; Yamamoto, Ayumi; Yamamoto, Hiroaki; Yamamoto, Kazuo

2010-01-01

Previously, we have shown that phenyl hydroquinone, a hepatic metabolite of the Ames test-negative carcinogen o-phenylphenol, efficiently induced aneuploidy in Saccharomyces cerevisiae by arresting the cell cycle at the G2/M transition as a result of the activation of the Hog1 (p38 MAPK homolog)-Swe1 (Wee1 homolog) pathway. In this experiment, we examined the aneuploidy forming effects of hydroquinone, a benzene metabolite, since both phenyl hydroquinone and hydroquinone are Ames-test negative carcinogens and share similar molecular structures. As was seen in phenyl hydroquinone, hydroquinone induced aneuploidy in yeast by delaying the cell cycle at the G2/M transition. Deficiencies in SWE1 and HOG1 abolished the hydroquinone-induced delay at the G2/M transition and aneuploidy formation. Furthermore, Hog1 was phosphorylated by hydroquinone, which may stabilize Swe1. These data indicate that the hydroquinone-induced G2/M transition checkpoint, which is activated by the Hog1-Swe1 pathway, plays a role in the formation of aneuploidy.

Multicore runup simulation by under water avalanche using two-layer 1D shallow water equations

NASA Astrophysics Data System (ADS)

Bagustara, B. A. R. H.; Simanjuntak, C. A.; Gunawan, P. H.

2018-03-01

The increasing of layers in shallow water equations (SWE) produces more dynamic model than the one-layer SWE model. The two-layer 1D SWE model has different density for each layer. This model becomes more dynamic and natural, for instance in the ocean, the density of water will decreasing from the bottom to the surface. Here, the source-centered hydro-static reconstruction (SCHR) numerical scheme will be used to approximate the solution of two-layer 1D SWE model, since this scheme is proved to satisfy the mathematical properties for shallow water equation. Additionally in this paper, the algorithm of SCHR is adapted to the multicore architecture. The simulation of runup by under water avalanche is elaborated here. The results show that the runup is depend on the ratio of density of each layers. Moreover by using grid sizes Nx = 8000, the speedup and efficiency by 2 threads are obtained 1.74779 times and 87.3896 % respectively. Nevertheless, by 4 threads the speedup and efficiency are obtained 2.93132 times and 73.2830 % respectively by similar number of grid sizes Nx = 8000.

Enhancing stress growth traits as well as phytochemical and antioxidant contents of Spiraea and Pittosporum under seaweed extract treatments.

PubMed

Elansary, Hosam O; Skalicka-Woźniak, Krystyna; King, Ian W

2016-08-01

Seaweed extracts (SWE) might play an important role in enhancing growth and phytochemical composition of medicinal shrubs. In this study, we investigate the morphological, physiological and biochemical effects of irrigation levels (100% and 50% of the evapotranspiration rate) coupled with a weekly treatment of SWE of Ascophyllum nodosum at 5 and 7 mL L(-1) as a soil drench or foliar spray on Spiraea nipponica "Snowmound" and Pittosporum eugenioides "Variegatum" grown in containers under controlled greenhouse conditions. In addition, the phenolic and flavonoid content, antioxidant capacity and lipid peroxidation in both plant species was largely enhanced while the proline accumulation was reduced. After 8 weeks of treatments, drought condition reduced plant vegetative growth and gas exchange, as well as leaf water potential, but increased the phenolic and flavonoid contents in leaves, their antioxidant capacities and proline content. The application of SWE enhanced the performance of both species during mild drought conditions by means of increasing leaf number and area, dry weights, plant height, gas exchange and leaf water potential. The maximum vegetative growth, physiological performance and phytochemical composition of both species was achieved using the drench SWE treatments (5 and 7 mL L(-1)) in moderate drought conditions, which improved the plant water status, stomatal conductance, and photosynthetic rate. SWE enhanced plant growth and the phytochemical composition and antioxidant capacity of plant leaves of both species during moderate drought conditions. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Evaluation of snowmelt simulation in the Weather Research and Forecasting model

NASA Astrophysics Data System (ADS)

Jin, Jiming; Wen, Lijuan

2012-05-01

The objective of this study is to better understand and improve snowmelt simulations in the advanced Weather Research and Forecasting (WRF) model by coupling it with the Community Land Model (CLM) Version 3.5. Both WRF and CLM are developed by the National Center for Atmospheric Research. The automated Snow Telemetry (SNOTEL) station data over the Columbia River Basin in the northwestern United States are used to evaluate snowmelt simulations generated with the coupled WRF-CLM model. These SNOTEL data include snow water equivalent (SWE), precipitation, and temperature. The simulations cover the period of March through June 2002 and focus mostly on the snowmelt season. Initial results show that when compared to observations, WRF-CLM significantly improves the simulations of SWE, which is underestimated when the release version of WRF is coupled with the Noah and Rapid Update Cycle (RUC) land surface schemes, in which snow physics is oversimplified. Further analysis shows that more realistic snow surface energy allocation in CLM is an important process that results in improved snowmelt simulations when compared to that in Noah and RUC. Additional simulations with WRF-CLM at different horizontal spatial resolutions indicate that accurate description of topography is also vital to SWE simulations. WRF-CLM at 10 km resolution produces the most realistic SWE simulations when compared to those produced with coarser spatial resolutions in which SWE is remarkably underestimated. The coupled WRF-CLM provides an important tool for research and forecasts in weather, climate, and water resources at regional scales.

Analysis of Extreme Snow Water Equivalent Data in Central New Hampshire

NASA Astrophysics Data System (ADS)

Vuyovich, C.; Skahill, B. E.; Kanney, J. F.; Carr, M.

2017-12-01

Heavy snowfall and snowmelt-related events have been linked to widespread flooding and damages in many regions of the U.S. Design of critical infrastructure in these regions requires spatial estimates of extreme snow water equivalent (SWE). In this study, we develop station specific and spatially explicit estimates of extreme SWE using data from fifteen snow sampling stations maintained by the New Hampshire Department of Environmental Services. The stations are located in the Mascoma, Pemigewasset, Winnipesaukee, Ossipee, Salmon Falls, Lamprey, Sugar, and Isinglass basins in New Hampshire. The average record length for the fifteen stations is approximately fifty-nine years. The spatial analysis of extreme SWE involves application of two Bayesian Hierarchical Modeling methods, one that assumes conditional independence, and another which uses the Smith max-stable process model to account for spatial dependence. We also apply additional max-stable process models, albeit not in a Bayesian framework, that better model the observed dependence among the extreme SWE data. The spatial process modeling leverages readily available and relevant spatially explicit covariate data. The noted additional max-stable process models also used the nonstationary winter North Atlantic Oscillation index, which has been observed to influence snowy weather along the east coast of the United States. We find that, for this data set, SWE return level estimates are consistently higher when derived using methods which account for the observed spatial dependence among the extreme data. This is particularly significant for design scenarios of relevance for critical infrastructure evaluation.

New Generation Sensor Web Enablement

PubMed Central

Bröring, Arne; Echterhoff, Johannes; Jirka, Simon; Simonis, Ingo; Everding, Thomas; Stasch, Christoph; Liang, Steve; Lemmens, Rob

2011-01-01

Many sensor networks have been deployed to monitor Earth’s environment, and more will follow in the future. Environmental sensors have improved continuously by becoming smaller, cheaper, and more intelligent. Due to the large number of sensor manufacturers and differing accompanying protocols, integrating diverse sensors into observation systems is not straightforward. A coherent infrastructure is needed to treat sensors in an interoperable, platform-independent and uniform way. The concept of the Sensor Web reflects such a kind of infrastructure for sharing, finding, and accessing sensors and their data across different applications. It hides the heterogeneous sensor hardware and communication protocols from the applications built on top of it. The Sensor Web Enablement initiative of the Open Geospatial Consortium standardizes web service interfaces and data encodings which can be used as building blocks for a Sensor Web. This article illustrates and analyzes the recent developments of the new generation of the Sensor Web Enablement specification framework. Further, we relate the Sensor Web to other emerging concepts such as the Web of Things and point out challenges and resulting future work topics for research on Sensor Web Enablement. PMID:22163760

Spatiotemporal variability of snow cover and snow water equivalent in the last three decades over Eurasia

NASA Astrophysics Data System (ADS)

Zhang, Yinsheng; Ma, Ning

2018-04-01

Changes in the extent and amount of snow cover in Eurasia are of great interest because of their vital impacts on the global climate system and regional water resource management. This study investigated the spatial and temporal variability of the snow cover extent (SCE) and snow water equivalent (SWE) of the continental Eurasia using the Northern Hemisphere Equal-Area Scalable Earth Grid (EASE-Grid) Weekly SCE data for 1972-2006 and the Global Monthly EASE-Grid SWE data for 1979-2004. The results indicated that, in general, the spatial extent of snow cover significantly decreased during spring and summer, but varied little during autumn and winter over Eurasia in the study period. The date at which snow cover began to disappear in spring has significantly advanced, whereas the timing of snow cover onset in autumn did not vary significantly during 1972-2006. The snow cover persistence period declined significantly in the western Tibetan Plateau as well as partial area of Central Asia and northwestern Russia, but varied little in other parts of Eurasia. "Snow-free breaks" (SFBs) with intermittent snow cover in the cold season were principally observed in the Tibetan Plateau and Central Asia, causing a low sensitivity of snow cover persistence period to the timings of snow cover onset and disappearance over the areas with shallow snow. The averaged SFBs were 1-14 weeks during the study period and the maximum intermittence could even reach 25 weeks in certain years. At a seasonal scale, SWE usually peaked in February or March, but fell gradually since April across Eurasia. Both annual mean and annual maximum SWE decreased significantly during 1979-2004 in most parts of Eurasia except for eastern Siberia as well as northwestern and northeastern China. The possible cross-platform inconsistencies between two passive microwave radiometers may cause uncertainties in the detected trends of SWE here, suggesting an urgent need of producing a long-term, more homogeneous SWE product in future.

ESA SSA Space Weather Services Supporting Space Surveillance and Tracking

NASA Astrophysics Data System (ADS)

Luntama, Juha-Pekka; Glover, Alexi; Hilgers, Alain; Fletcher, Emmet

2012-07-01

ESA Space Situational Awareness (SSA) Preparatory Programme was started in 2009. The objective of the programme is to support the European independent utilisation of and access to space research or services. This will be performed through providing timely and quality data, information, services and knowledge regarding the environment, the threats and the sustainable exploitation of the outer space surrounding the planet Earth. SSA serves the implementation of the strategic missions of the European Space Policy based on the peaceful uses of the outer space by all states, by supporting the autonomous capacity to securely and safely operate the critical European space infrastructures. The Space Weather (SWE) Segment of the SSA will provide user services related to the monitoring of the Sun, the solar wind, the radiation belts, the magnetosphere and the ionosphere. These services will include near real time information and forecasts about the characteristics of the space environment and predictions of space weather impacts on sensitive spaceborne and ground based infrastructure. The SSA SWE system will also include establishment of a permanent database for analysis, model development and scientific research. These services are will support a wide variety of user domains including spacecraft designers, spacecraft operators, human space flights, users and operators of transionospheric radio links, and space weather research community. The precursor SWE services to be established starting in 2010. This presentation provides an overview of the ESA SSA SWE services focused on supporting the Space Surveillance and Tracking users. This services include estimates of the atmospheric drag and archive and forecasts of the geomagnetic and solar indices. In addition, the SSA SWE system will provide nowcasts of the ionospheric group delay to support mitigation of the ionospheric impact on radar signals. The paper will discuss the user requirements for the services, the data requirements and the foreseen development needs for the ESA SSA SWE system before the full service capability is available.

Simulating the Snow Water Equivalent and its changing pattern over Nepal

NASA Astrophysics Data System (ADS)

Niroula, S.; Joseph, J.; Ghosh, S.

2016-12-01

Snow fall in the Himalayan region is one of the primary sources of fresh water, which accounts around 10% of total precipitation of Nepal. Snow water is an intricate variable in terms of its global and regional estimates whose complexity is favored by spatial variability linked with rugged topography. The study is primarily focused on simulation of Snow Water Equivalent (SWE) by the use of a macroscale hydrologic model, Variable Infiltration Capacity (VIC). As whole Nepal including its Himalayas lies under the catchment of Ganga River in India, contributing at least 40% of annual discharge of Ganges, this model was run in the entire watershed that covers part of Tibet and Bangladesh as well. Meteorological inputs for 29 years (1979-2007) are drawn from ERA-INTERIM and APHRODITE dataset for horizontal resolution of 0.25 degrees. The analysis was performed to study temporal variability of SWE in the Himalayan region of Nepal. The model was calibrated by observed stream flows of the tributaries of the Gandaki River in Nepal which ultimately feeds river Ganga. Further, the simulated SWE is used to estimate stream flow in this river basin. Since Nepal has a greater snow cover accumulation in monsoon season than in winter at high altitudes, seasonality fluctuations in SWE affecting the stream flows are known. The model provided fair estimates of SWE and stream flow as per statistical analysis. Stream flows are known to be sensitive to the changes in snow water that can bring a negative impact on power generation in a country which has huge hydroelectric potential. In addition, our results on simulated SWE in second largest snow-fed catchment of the country will be helpful for reservoir management, flood forecasting and other water resource management issues. Keywords: Hydrology, Snow Water Equivalent, Variable Infiltration Capacity, Gandaki River Basin, Stream Flow

Improving Snow Modeling by Assimilating Observational Data Collected by Citizen Scientists

NASA Astrophysics Data System (ADS)

Crumley, R. L.; Hill, D. F.; Arendt, A. A.; Wikstrom Jones, K.; Wolken, G. J.; Setiawan, L.

2017-12-01

Modeling seasonal snow pack in alpine environments includes a multiplicity of challenges caused by a lack of spatially extensive and temporally continuous observational datasets. This is partially due to the difficulty of collecting measurements in harsh, remote environments where extreme gradients in topography exist, accompanied by large model domains and inclement weather. Engaging snow enthusiasts, snow professionals, and community members to participate in the process of data collection may address some of these challenges. In this study, we use SnowModel to estimate seasonal snow water equivalence (SWE) in the Thompson Pass region of Alaska while incorporating snow depth measurements collected by citizen scientists. We develop a modeling approach to assimilate hundreds of snow depth measurements from participants in the Community Snow Observations (CSO) project (www.communitysnowobs.org). The CSO project includes a mobile application where participants record and submit geo-located snow depth measurements while working and recreating in the study area. These snow depth measurements are randomly located within the model grid at irregular time intervals over the span of four months in the 2017 water year. This snow depth observation dataset is converted into a SWE dataset by employing an empirically-based, bulk density and SWE estimation method. We then assimilate this data using SnowAssim, a sub-model within SnowModel, to constrain the SWE output by the observed data. Multiple model runs are designed to represent an array of output scenarios during the assimilation process. An effort to present model output uncertainties is included, as well as quantification of the pre- and post-assimilation divergence in modeled SWE. Early results reveal pre-assimilation SWE estimations are consistently greater than the post-assimilation estimations, and the magnitude of divergence increases throughout the snow pack evolution period. This research has implications beyond the Alaskan context because it increases our ability to constrain snow modeling outputs by making use of snow measurements collected by non-expert, citizen scientists.

Wide-area mapping of snow water equivalent by Sentinel-1&2 data

NASA Astrophysics Data System (ADS)

Conde, Vasco; Nico, Giovanni; Catalao, Joao; Kontu, Anna; Gritsevich, Maria

2017-04-01

The mapping of snow physical properties over large mountain areas of remote areas is an important topic in both climatological studies and hydrological models where the effects of snow melting are modeled and used to forecast extreme flood events. Usually, these models are run using in-situ measurements of snow which are expensive and statistically not representative of the spatial distribution of snow properties due to slope orientation of terrain, local terrain morphology and height as well as vegetation cover. In this work we investigate the use of data acquired by Sentinel-1 and 2 missions using a C-band SAR and multispectral sensor, respectively. The Sentinel-1 SAR data are processed to estimate the Snow Water Equivalent (SWE) using both the radar amplitude and the output of the SAR interferometry processing. Both approaches need in-situ data to process SAR data and calibrate SWE estimates. The use of SAR amplitude to estimate the SWE is well established and the basic idea is that the radar signal backscattered by snow is related to the SWE so, after modeling the relationship between these two quantities at the site of in-situ measurements this relationship can be used to map the SWE at all site where the SAR amplitude information is available. The physical principle used by SAR interferometry is that of phase delay due to propagation in a non-dispersive medium. This implies that the snow is supposed to be dry in order to allow the propagation of the SAR signal. Sentinel-2 images have been used to get land-use maps and identify areas covered by vegetation. Finland has been chosen as a study region with in-situ measurements acquired thanks to the availability of rich database of in-situ measurements of SWE. Sentinel data used in this work have been acquired starting from November 2015. Publication supported by FCT- project UID/GEO/50019/2013 - Instituto Dom Luiz.

Assessment of biopsy-proven liver fibrosis by two-dimensional shear wave elastography: An individual patient data-based meta-analysis.

PubMed

Herrmann, Eva; de Lédinghen, Victor; Cassinotto, Christophe; Chu, Winnie C-W; Leung, Vivian Y-F; Ferraioli, Giovanna; Filice, Carlo; Castera, Laurent; Vilgrain, Valérie; Ronot, Maxime; Dumortier, Jérôme; Guibal, Aymeric; Pol, Stanislas; Trebicka, Jonel; Jansen, Christian; Strassburg, Christian; Zheng, Rongqin; Zheng, Jian; Francque, Sven; Vanwolleghem, Thomas; Vonghia, Luisa; Manesis, Emanuel K; Zoumpoulis, Pavlos; Sporea, Ioan; Thiele, Maja; Krag, Aleksander; Cohen-Bacrie, Claude; Criton, Aline; Gay, Joel; Deffieux, Thomas; Friedrich-Rust, Mireen

2018-01-01

Two-dimensional shear wave elastography (2D-SWE) has proven to be efficient for the evaluation of liver fibrosis in small to moderate-sized clinical trials. We aimed at running a larger-scale meta-analysis of individual data. Centers which have worked with Aixplorer ultrasound equipment were contacted to share their data. Retrospective statistical analysis used direct and paired receiver operating characteristic and area under the receiver operating characteristic curve (AUROC) analyses, accounting for random effects. Data on both 2D-SWE and liver biopsy were available for 1,134 patients from 13 sites, as well as on successful transient elastography in 665 patients. Most patients had chronic hepatitis C (n = 379), hepatitis B (n = 400), or nonalcoholic fatty liver disease (n = 156). AUROCs of 2D-SWE in patients with hepatitis C, hepatitis B, and nonalcoholic fatty liver disease were 86.3%, 90.6%, and 85.5% for diagnosing significant fibrosis and 92.9%, 95.5%, and 91.7% for diagnosing cirrhosis, respectively. The AUROC of 2D-SWE was 0.022-0.084 (95% confidence interval) larger than the AUROC of transient elastography for diagnosing significant fibrosis (P = 0.001) and 0.003-0.034 for diagnosing cirrhosis (P = 0.022) in all patients. This difference was strongest in hepatitis B patients. 2D-SWE has good to excellent performance for the noninvasive staging of liver fibrosis in patients with hepatitis B; further prospective studies are needed for head-to-head comparison between 2D-SWE and other imaging modalities to establish disease-specific appropriate cutoff points for assessment of fibrosis stage. (Hepatology 2018;67:260-272). © 2017 The Authors. Hepatology published by Wiley Periodicals, Inc., on behalf of the American Association for the Study of Liver Diseases.

Seasonal and interannual variations in the influence of cloud cover variability on snowpack and streamflow in the western U.S.

NASA Astrophysics Data System (ADS)

Sumargo, E.; Cayan, D. R.

2016-12-01

Solar radiation (S) is a key driver of snowmelt and water fluxes, but its effect varies depending on time of year and also upon the hydrological character (e.g., dry or wet) of a given year. In this study, we use remote sensed S to quantify cloudiness variability and its effects on snowmelt and streamflow across mountain basins in the western U.S. We utilize 20 years (1996-2015) of NASA/NOAA GOES-derived cloud albedo (αcloud) at 4-km daily samples to estimate S over relatively fine spatial and temporal resolution during Feb-Jul when snowmelt is most active. Daily snow water equivalent (SWE) records from >200 CDEC and SNOTEL locations, along with daily stream discharge (Q) from USGS HCDN records are used to compute day-to-day changes (dSWE and dQ). Multivariate linear regression models of dSWE and dQ are constructed for each month, wherein αcloud from several days prior up to the concurrent day are the predictors. In Feb-May, the results show predominantly negative correlations between αcloud and dSWE, confirming the cloud-shading effect in preserving snowpack and reducing runoff. The influence of cloudiness variability on snowpack, denoted by the coefficient of determination (R2) between the measured and modeled dSWE, amounts 4%-73% over Feb-Jul, averaging 20% in the northwest and 26% in the southwest. The dQ case exhibits similar patterns, but lower explained variance. In Jun-Jul, most locations in both dSWE and dQ cases display positive correlation but with diminished R2, presumably reflecting the drying effect of summertime. In comparing dry and wet years, the R2 is somewhat higher in dry years, suggesting that the importance of cloud cover and the associated solar insolation variability is higher in cases with greater influence from other hydrological factors, including heavy precipitation events and fluctuations associated with a higher snowpack.

Assessment of liver fibrosis with 2-D shear wave elastography in comparison to transient elastography and acoustic radiation force impulse imaging in patients with chronic liver disease.

PubMed

Gerber, Ludmila; Kasper, Daniela; Fitting, Daniel; Knop, Viola; Vermehren, Annika; Sprinzl, Kathrin; Hansmann, Martin L; Herrmann, Eva; Bojunga, Joerg; Albert, Joerg; Sarrazin, Christoph; Zeuzem, Stefan; Friedrich-Rust, Mireen

2015-09-01

Two-dimensional shear wave elastography (2-D SWE) is an ultrasound-based elastography method integrated into a conventional ultrasound machine. It can evaluate larger regions of interest and, therefore, might be better at determining the overall fibrosis distribution. The aim of this prospective study was to compare 2-D SWE with the two best evaluated liver elastography methods, transient elastography and acoustic radiation force impulse (point SWE using acoustic radiation force impulse) imaging, in the same population group. The study included 132 patients with chronic hepatopathies, in which liver stiffness was evaluated using transient elastography, acoustic radiation force impulse imaging and 2-D SWE. The reference methods were liver biopsy for the assessment of liver fibrosis (n = 101) and magnetic resonance imaging/computed tomography for the diagnosis of liver cirrhosis (n = 31). No significant difference in diagnostic accuracy, assessed as the area under the receiver operating characteristic curve (AUROC), was found between the three elastography methods (2-D SWE, transient elastography, acoustic radiation force impulse imaging) for the diagnosis of significant and advanced fibrosis and liver cirrhosis in the "per protocol" (AUROCs for fibrosis stages ≥2: 0.90, 0.95 and 0.91; for fibrosis stage [F] ≥3: 0.93, 0.95 and 0.94; for F = 4: 0.92, 0.96 and 0.92) and "intention to diagnose" cohort (AUROCs for F ≥2: 0.87, 0.92 and 0.91; for F ≥3: 0.91, 0.93 and 0.94; for F = 4: 0.88, 0.90 and 0.89). Therefore, 2-D SWE, ARFI imaging and transient elastography seem to be comparably good methods for non-invasive assessment of liver fibrosis. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Snow Water Equivalent Retrieval Using Multitemporal COSMO Skymed X-Band SAR Images To Inform Water Systems Operation

NASA Astrophysics Data System (ADS)

Denaro, S.; Del Gobbo, U.; Castelletti, A.; Tebaldini, S.; Monti Guarnieri, A.

2015-12-01

In this work, we explore the use of exogenous snow-related information for enhancing the operation of water facilities in snow dominated watersheds. Traditionally, such information is assimilated into short-to-medium term streamflow forecasts, which are then used to inform water systems operation. Here, we adopt an alternative model-free approach, where the policy is directly conditioned upon a small set of selected observational data able to surrogate the snow-pack dynamics. In snow-fed water systems, the Snow Water Equivalent (SWE) stored in the basin often represents the largest contribution to the future season streamflow. The SWE estimation process is challenged by the high temporal and spatial variability of snow-pack and snow properties. Traditional retrieval methods, based on few ground sensors and optical satellites, often fail at representing the spatial diversity of snow conditions over large basins and at producing continuous (gap-free) data at the high sample frequency (e.g. daily) required to optimally control water systems. Against this background, SWE estimates from remote sensed radar products stand out, being able to acquire spatial information with no dependence on cloud coverage. In this work, we propose a technique for retrieving SWE estimates from Synthetic Aperture Radar (SAR) Cosmo SkyMed X-band images: a regression model, calibrated on ground SWE measurements, is implemented on dry snow maps obtained through a multi-temporal approach. The unprecedented spatial scale of this application is novel w.r.t. state of the art radar analysis conducted on limited spatial domains. The operational value of the SAR retrieved SWE estimates is evaluated based on ISA, a recently developed information selection and assessment framework. The method is demonstrated on a snow-rain fed river basin in the Italian Alps. Preliminary results show SAR images have a good potential for monitoring snow conditions and for improving water management operations.

Snowmelt sensitivity to warmer temperatures: a field-validated model analysis, southern Sierra Nevada, California

NASA Astrophysics Data System (ADS)

Musselman, K. N.; Molotch, N. P.; Margulis, S. A.

2014-12-01

We present model simulations of climate change impacts on snowmelt processes over a 1600 km2 area in the southern Sierra Nevada, including western Sequoia National Park. The domain spans a 3600 m elevation gradient and ecosystems ranging from semi-arid grasslands to giant sequoia groves to alpine tundra. Three reference years were evaluated: a moderately dry snow season (23% below average SWE), an average snow season (7% above average SWE), and a moderately wet snow season (54% above average SWE). The Alpine3D model was run for the reference years and results were evaluated against data from a multi-scale measurement campaign that included repeated manual snow courses and basin-scale snow surveys, dozens of automated snow depth sensors, and automated SWE stations. Compared to automated measurements, the model represented the date of snow disappearance within two days. Compared to manual measurements, model SWE RMSE values for the average and wet snow seasons were highly correlated (R2=0.89 and R2=0.73) with the distance of SWE measurements from the nearest precipitation gauge used to force the model; no significant correlation was found with elevation. The results suggest that Alpine3D is highly accurate during the melt season and that precipitation uncertainty may critically limit snow model accuracy. The air temperature measured at 19 regional stations for the three reference years was modified by +1°C to +6°C to simulate the impact of warmer temperatures on snowmelt dynamics over the 3600 m elevation gradient. For all years, progressively warmer temperatures caused the seasonal SWE centroid to shift earlier and higher in elevation. At forested middle elevations, 70 - 80% of the present-day snowpack volume is lost in a +2°C scenario; 30 - 40% of that change is a result of precipitation phase shift and the remainder is due to enhanced melt. At all elevations, spring and fall snowpack was most sensitive to warmer temperatures; mid-winter sensitivity was least for elevations >3100 m. Interestingly, the dominant effect of warmer temperatures on snowmelt was a reduction in daily melt rates. The drier year was most sensitive to temperature changes with a greater decrease in the number of days with high melt rates. The results offer insight into the sensitivity of snowmelt processes to warmer temperatures in the Sierra Nevada.

Long-term analyses of snow dynamics within the french Alps on the 1900-2100 period. Analyses of historical snow water equivalent observations, modelisations and projections of a hundred of snow courses.

NASA Astrophysics Data System (ADS)

Mathevet, T.; Joel, G.; Gottardi, F.; Nemoz, B.

2017-12-01

The aim of this communication is to present analyses of climate variability and change on snow water equivalent (SWE) observations, reconstructions (1900-2016) and scenarii (2020-2100) of a hundred of snow courses dissiminated within the french Alps. This issue became particularly important since a decade, in regions where snow variability had a large impact on water resources availability, poor snow conditions in ski resorts and artificial snow production. As a water resources manager in french mountainuous regions, EDF (french hydropower company) has developed and managed a hydrometeorological network since 1950. A recent data rescue research allowed to digitize long term SWE manual measurments of a hundred of snow courses within the french Alps. EDF have been operating an automatic SWE sensors network, complementary to the snow course network. Based on numerous SWE observations time-series and snow accumulation and melt model (Garavaglia et al., 2017), continuous daily historical SWE time-series have been reconstructed within the 1950-2016 period. These reconstructions have been extented to 1900 using 20 CR reanalyses (ANATEM method, Kuentz et al., 2015) and up to 2100 using GIEC Climate Change scenarii. Considering various mountainous areas within the french Alps, this communication focuses on : (1) long term (1900-2016) analyses of variability and trend of total precipitation, air temperature, snow water equivalent, snow line altitude, snow season length , (2) long term variability of hydrological regime of snow dominated watersheds and (3) future trends (2020 -2100) using GIEC Climate Change scenarii. Comparing historical period (1950-1984) to recent period (1984-2016), quantitative results within a region in the north Alps (Maurienne) shows an increase of air temperature by 1.2 °C, an increase of snow line height by 200m, a reduction of SWE by 200 mm/year and a reduction of snow season length by 15 days. These analyses will be extended from north to south of the Alps, on a region spanning 200 km. Caracterisation of the increase of snow line height and SWE reduction are particularly important at a local and watershed scale. This long term change of snow dynamics within moutainuous regions both impacts snow resorts and artificial snow production developments and multi-purposes dam reservoirs managments.

Using Confidence Intervals and Recurrence Intervals to Determine Precipitation Delivery Mechanisms Responsible for Mass Wasting Events.

NASA Astrophysics Data System (ADS)

Ulizio, T. P.; Bilbrey, C.; Stoyanoff, N.; Dixon, J. L.

2015-12-01

Mass wasting events are geologic hazards that impact human life and property across a variety of landscapes. These movements can be triggered by tectonic activity, anomalous precipitation events, or both; acting to decrease the factor of safety ratio on a hillslope to the point of failure. There exists an active hazard landscape in the West Boulder River drainage of Park Co., MT in which the mechanisms of slope failure are unknown. It is known that region has not seen significant tectonic activity within the last decade, leaving anomalous precipitation events as the likely trigger for slope failures in the landscape. Precipitation can be delivered to a landscape via rainfall or snow; it was the aim of this study to determine the precipitation delivery mechanism most likely responsible for movements in the West Boulder drainage following the Jungle Wildfire of 2006. Data was compiled from four SNOTEL sites in the surrounding area, spanning 33 years, focusing on, but not limited to; maximum snow water equivalent (SWE) values in a water year, median SWE values on the date which maximum SWE was recorded in a water year, the total precipitation accumulated in a water year, etc. Means were computed and 99% confidence intervals were constructed around these means. Recurrence intervals and exceedance probabilities were computed for maximum SWE values and total precipitation accumulated in a water year to determine water years with anomalous precipitation. It was determined that the water year 2010-2011 received an anomalously high amount of SWE, and snow melt in the spring of this water year likely triggered recent mass waste movements. This data is further supported by Google Earth imagery, showing movements between 2009 and 2011. Return intervals for the maximum SWE value in 2010-11 for the Placer Basin SNOTEL site was 34 years, while return intervals for the Box Canyon and Monument Peak SNOTEL sites were 17.5 and 17 years respectively. Max SWE values lie outside the upper bound of the 99% confidence interval at all SNOTEL sites while precipitation accumulated in the form of rain is within the expected average, indicating an anomalously snow year and average amounts of rainfall during the same water year. This information can be used to better predict circumstances leading to slope failures in northern latitude alpine landscapes.

An assessment of two automated snow water equivalent instruments during the WMO Solid Precipitation Intercomparison Experiment

NASA Astrophysics Data System (ADS)

Smith, Craig D.; Kontu, Anna; Laffin, Richard; Pomeroy, John W.

2017-01-01

During the World Meteorological Organization (WMO) Solid Precipitation Intercomparison Experiment (SPICE), automated measurements of snow water equivalent (SWE) were made at the Sodankylä (Finland), Weissfluhjoch (Switzerland) and Caribou Creek (Canada) SPICE sites during the northern hemispheric winters of 2013/14 and 2014/15. Supplementary intercomparison measurements were made at Fortress Mountain (Kananaskis, Canada) during the 2013/14 winter. The objectives of this analysis are to compare automated SWE measurements with a reference, comment on their performance and, where possible, to make recommendations on how to best use the instruments and interpret their measurements. Sodankylä, Caribou Creek and Fortress Mountain hosted a Campbell Scientific CS725 passive gamma radiation SWE sensor. Sodankylä and Weissfluhjoch hosted a Sommer Messtechnik SSG1000 snow scale. The CS725 operating principle is based on measuring the attenuation of soil emitted gamma radiation by the snowpack and relating the attenuation to SWE. The SSG1000 measures the mass of the overlying snowpack directly by using a weighing platform and load cell. Manual SWE measurements were obtained at the intercomparison sites on a bi-weekly basis over the accumulation-ablation periods using bulk density samplers. These manual measurements are considered to be the reference for the intercomparison. Results from Sodankylä and Caribou Creek showed that the CS725 generally overestimates SWE as compared to manual measurements by roughly 30-35 % with correlations (r2) as high as 0.99 for Sodankylä and 0.90 for Caribou Creek. The RMSE varied from 30 to 43 mm water equivalent (mm w.e.) and from 18 to 25 mm w.e. at Sodankylä and Caribou Creek, which had respective SWE maximums of approximately 200 and 120 mm w.e. The correlation at Fortress Mountain was 0.94 (RMSE of 48 mm w.e. with a maximum SWE of approximately 650 mm w.e.) with no systematic overestimation. The SSG1000 snow scale, having a different measurement principle, agreed quite closely with the manual measurements at Sodankylä and Weissfluhjoch throughout the periods when data were available (r2 as high as 0.99 and RMSE from 8 to 24 mm w.e. at Sodankylä and from 56 to 59 mm w.e. at Weissfluhjoch, where maximum SWE was approximately 850 mm w.e.). When the SSG1000 was compared to the CS725 at Sodankylä, the agreement was linear until the start of ablation when the positive bias in the CS725 increases substantially relative to the SSG1000. Since both Caribou Creek and Sodankylä have sandy soil, water from the snowpack readily infiltrates into the soil during melt, even if the soil is frozen. However, the CS725 does not differentiate this water from the unmelted snow. This issue can be identified, at least during the late spring ablation period, with soil moisture and temperature observations like those measured at Caribou Creek. With a less permeable soil and surface runoff, the increase in the instrument bias during ablation is not as significant, as shown by the Fortress Mountain intercomparison.

Enable Web-Based Tracking and Guiding by Integrating Location-Awareness with the World Wide Web

ERIC Educational Resources Information Center

Zhou, Rui

2008-01-01

Purpose: The aim of this research is to enable web-based tracking and guiding by integrating location-awareness with the Worldwide Web so that the users can use various location-based applications without installing extra software. Design/methodology/approach: The concept of web-based tracking and guiding is introduced and the relevant issues are…

A web-based support for pregnant women and new mothers with type 1 diabetes mellitus in Sweden (MODIAB-Web): study protocol for a randomized controlled trial.

PubMed

Adolfsson, Annsofie; Linden, Karolina; Sparud-Lundin, Carina; Larsson, Per-Göran; Berg, Marie

2014-12-29

Women with type 1 diabetes face particular demands in their lives in relation to childbearing. During pregnancy, in order to optimize the probability of giving birth to a healthy child, their blood glucose levels need to be as normal as possible. After childbirth, they experience a 'double stress': in addition to the ordinary challenges they face as new mothers, they also need to focus on getting their blood glucose levels normal. To improve self-management of diabetes and overall well-being in women with type 1 diabetes, a person-centered web-based support was designed to be tested in a randomized controlled trial (RCT) to be used during pregnancy and early motherhood. This protocol outlines the design of this RCT, which will evaluate the effectiveness of the specially designed web-based support for mothers with type 1 diabetes in Sweden. The study is designed as an RCT. The web support consists of three parts: 1) evidence-based information, 2) a self-care diary, and 3) communication with peers. The primary outcome is general well-being evaluated with the Well-Being Questionnaire short version (W-BQ12) and diabetes management evaluated with the Diabetes Empowerment Scale, short version (SWE-DES). Women attending six hospital-based antenatal care centers in Sweden are invited to participate. The inclusion period is November 2011 to late 2014. The allocation of participants to web support (intervention group) and to usual care (control group) is equal (1:1). In total, 68 participants in each group will be needed to reach a statistical power of 80% with significance level 0.05. The web support is expected to strengthen the women's personal capacity and autonomy during pregnancy, breastfeeding, and early motherhood, leading to optimal well-being and diabetes management. ClinicalTrials.gov: NCT01565824 (registration date March 27th 2012).

Web 2.0 Systems in the Brigade Combat Team as an Enabler of Mission Command: A Dialectic in Information Discourse

DTIC Science & Technology

2016-06-10

WEB 2.0 SYSTEMS IN THE BRIGADE COMBAT TEAM AS AN ENABLER OF MISSION COMMAND: A DIALECTIC IN INFORMATION DISCOURSE A thesis......This qualitative research in the field of information science aims to examine the use of Web 2.0 systems in the Brigade Combat Team as an enabler of

Towards Improved Snow Water Equivalent Estimation via GRACE Assimilation

NASA Technical Reports Server (NTRS)

Forman, Bart; Reichle, Rofl; Rodell, Matt

2011-01-01

Passive microwave (e.g. AMSR-E) and visible spectrum (e.g. MODIS) measurements of snow states have been used in conjunction with land surface models to better characterize snow pack states, most notably snow water equivalent (SWE). However, both types of measurements have limitations. AMSR-E, for example, suffers a loss of information in deep/wet snow packs. Similarly, MODIS suffers a loss of temporal correlation information beyond the initial accumulation and final ablation phases of the snow season. Gravimetric measurements, on the other hand, do not suffer from these limitations. In this study, gravimetric measurements from the Gravity Recovery and Climate Experiment (GRACE) mission are used in a land surface model data assimilation (DA) framework to better characterize SWE in the Mackenzie River basin located in northern Canada. Comparisons are made against independent, ground-based SWE observations, state-of-the-art modeled SWE estimates, and independent, ground-based river discharge observations. Preliminary results suggest improved SWE estimates, including improved timing of the subsequent ablation and runoff of the snow pack. Additionally, use of the DA procedure can add vertical and horizontal resolution to the coarse-scale GRACE measurements as well as effectively downscale the measurements in time. Such findings offer the potential for better understanding of the hydrologic cycle in snow-dominated basins located in remote regions of the globe where ground-based observation collection if difficult, if not impossible. This information could ultimately lead to improved freshwater resource management in communities dependent on snow melt as well as a reduction in the uncertainty of river discharge into the Arctic Ocean.

Evaluation of gridded snow water equivalent and satellite snow cover products for mountain basins in a hydrologic model

USGS Publications Warehouse

Dressler, K.A.; Leavesley, G.H.; Bales, R.C.; Fassnacht, S.R.

2006-01-01

The USGS precipitation-runoff modelling system (PRMS) hydrologic model was used to evaluate experimental, gridded, 1 km2 snow-covered area (SCA) and snow water equivalent (SWE) products for two headwater basins within the Rio Grande (i.e. upper Rio Grande River basin) and Salt River (i.e. Black River basin) drainages in the southwestern USA. The SCA product was the fraction of each 1 km2 pixel covered by snow and was derived from NOAA advanced very high-resolution radiometer imagery. The SWE product was developed by multiplying the SCA product by SWE estimates interpolated from National Resources Conservation Service snow telemetry point measurements for a 6 year period (1995-2000). Measured SCA and SWE estimates were consistently lower than values estimated from temperature and precipitation within PRMS. The greatest differences occurred in the relatively complex terrain of the Rio Grande basin, as opposed to the relatively homogeneous terrain of the Black River basin, where differences were small. Differences between modelled and measured snow were different for the accumulation period versus the ablation period and had an elevational trend. Assimilating the measured snowfields into a version of PRMS calibrated to achieve water balance without assimilation led to reduced performance in estimating streamflow for the Rio Grande and increased performance in estimating streamflow for the Black River basin. Correcting the measured SCA and SWE for canopy effects improved simulations by adding snow mostly in the mid-to-high elevations, where satellite estimates of SCA are lower than model estimates. Copyright ?? 2006 John Wiley & Sons, Ltd.

Measuring shear-wave speed with point shear-wave elastography and MR elastography: a phantom study

PubMed Central

Kishimoto, Riwa; Suga, Mikio; Koyama, Atsuhisa; Omatsu, Tokuhiko; Tachibana, Yasuhiko; Ebner, Daniel K; Obata, Takayuki

2017-01-01

Objectives To compare shear-wave speed (SWS) measured by ultrasound-based point shear-wave elastography (pSWE) and MR elastography (MRE) on phantoms with a known shear modulus, and to assess method validity and variability. Methods 5 homogeneous phantoms of different stiffnesses were made. Shear modulus was measured by a rheometer, and this value was used as the standard. 10 SWS measurements were obtained at 4 different depths with 1.0–4.5 MHz convex (4C1) and 4.0–9.0 MHz linear (9L4) transducers using pSWE. MRE was carried out once per phantom, and SWSs at 5 different depths were obtained. These SWSs were then compared with those from a rheometer using linear regression analyses. Results SWSs obtained with both pSWE as well as MRE had a strong correlation with those obtained by a rheometer (R2>0.97). The relative difference in SWS between the procedures was from −25.2% to 25.6% for all phantoms, and from −8.1% to 6.9% when the softest and hardest phantoms were excluded. Depth dependency was noted in the 9L4 transducer of pSWE and MRE. Conclusions SWSs from pSWE and MRE showed a good correlation with a rheometer-determined SWS. Although based on phantom studies, SWSs obtained with these methods are not always equivalent, the measurement can be thought of as reliable and these SWSs were reasonably close to each other for the middle range of stiffness within the measurable range. PMID:28057657

Does shear wave ultrasound independently predict axillary lymph node metastasis in women with invasive breast cancer?

PubMed

Evans, Andrew; Rauchhaus, Petra; Whelehan, Patsy; Thomson, Kim; Purdie, Colin A; Jordan, Lee B; Michie, Caroline O; Thompson, Alastair; Vinnicombe, Sarah

2014-01-01

Shear wave elastography (SWE) shows promise as an adjunct to greyscale ultrasound examination in assessing breast masses. In breast cancer, higher lesion stiffness on SWE has been shown to be associated with features of poor prognosis. The purpose of this study was to assess whether lesion stiffness at SWE is an independent predictor of lymph node involvement. Patients with invasive breast cancer treated by primary surgery, who had undergone SWE examination were eligible. Data were retrospectively analysed from 396 consecutive patients. The mean stiffness values were obtained using the Aixplorer® ultrasound machine from SuperSonic Imagine Ltd. Measurements were taken from a region of interest positioned over the stiffest part of the abnormality. The average of the mean stiffness value obtained from each of two orthogonal image planes was used for analysis. Associations between lymph node involvement and mean lesion stiffness, invasive cancer size, histologic grade, tumour type, ER expression, HER-2 status and vascular invasion were assessed using univariate and multivariate logistic regression. At univariate analysis, invasive size, histologic grade, HER-2 status, vascular invasion, tumour type and mean stiffness were significantly associated with nodal involvement. Nodal involvement rates ranged from 7 % for tumours with mean stiffness <50 kPa to 41 % for tumours with a mean stiffness of >150 kPa. At multivariate analysis, invasive size, tumour type, vascular invasion, and mean stiffness maintained independent significance. Mean stiffness at SWE is an independent predictor of lymph node metastasis and thus can confer prognostic information additional to that provided by conventional preoperative tumour assessment and staging.

Shear-wave elastography quantitative assessment of the male breast: added value to distinguish benign and malignant palpable masses.

PubMed

Crombé, Amandine; Hurtevent-Labrot, Gabrielle; Asad-Syed, Maryam; Palussière, Jean; MacGrogan, Gaetan; Kind, Michèle; Ferron, Stéphane

2018-02-01

To evaluate the ability of shear-wave elastography (SWE) to distinguish between benign and malignant palpable masses of the adult male breast. Clinical examination, mammography, B-mode and Doppler ultrasound findings and SWE quantitative parameters were compared in 50 benign lesions (including 40 gynaecomastias) and 15 malignant lesions (invasive ductal carcinomas) from 65 patients who were consecutively addressed for specialized advice at our comprehensive cancer centre. Mean elasticity (El mean), maximum elasticity (El max), El mean of the surrounding fatty tissue and lesion to fat ratio (El ratio) were reported for each patient. Malignant masses displayed significantly higher El mean (p < 0.0001), El max (p < 0.0001) and El ratio (p < 0.0001) compared to benign masses without overlap of values between the two groups. By adding SWE to clinical examination, mammography and ultrasound, all the lesions would have been retrospectively correctly diagnosed as benign or malignant. One false positive could have been downstaged, 14/65 undetermined masses could have been correctly reclassified as 4 malignant and 10 benign lesions, for which biopsies could have consequently been avoided. Evaluation of male breast palpable masses by SWE demonstrates that malignant masses are significantly stiffer lesions and may improve diagnostic management when clinical examination, mammography and conventional ultrasound are doubtful. Advances in knowledge: Quantitative SWE is feasible in male breast and could be of great interest to help classify doubtful lesions after classical clinical and radiological evaluations, probably because of different anatomy and different tumours epidemiology compared with female breast.

Shear-Wave Elastography: Basic Physics and Musculoskeletal Applications.

PubMed

Taljanovic, Mihra S; Gimber, Lana H; Becker, Giles W; Latt, L Daniel; Klauser, Andrea S; Melville, David M; Gao, Liang; Witte, Russell S

2017-01-01

In the past 2 decades, sonoelastography has been progressively used as a tool to help evaluate soft-tissue elasticity and add to information obtained with conventional gray-scale and Doppler ultrasonographic techniques. Recently introduced on clinical scanners, shear-wave elastography (SWE) is considered to be more objective, quantitative, and reproducible than compression sonoelastography with increasing applications to the musculoskeletal system. SWE uses an acoustic radiation force pulse sequence to generate shear waves, which propagate perpendicular to the ultrasound beam, causing transient displacements. The distribution of shear-wave velocities at each pixel is directly related to the shear modulus, an absolute measure of the tissue's elastic properties. Shear-wave images are automatically coregistered with standard B-mode images to provide quantitative color elastograms with anatomic specificity. Shear waves propagate faster through stiffer contracted tissue, as well as along the long axis of tendon and muscle. SWE has a promising role in determining the severity of disease and treatment follow-up of various musculoskeletal tissues including tendons, muscles, nerves, and ligaments. This article describes the basic ultrasound physics of SWE and its applications in the evaluation of various traumatic and pathologic conditions of the musculoskeletal system. © RSNA, 2017.

Deep learning based classification of breast tumors with shear-wave elastography.

PubMed

Zhang, Qi; Xiao, Yang; Dai, Wei; Suo, Jingfeng; Wang, Congzhi; Shi, Jun; Zheng, Hairong

2016-12-01

This study aims to build a deep learning (DL) architecture for automated extraction of learned-from-data image features from the shear-wave elastography (SWE), and to evaluate the DL architecture in differentiation between benign and malignant breast tumors. We construct a two-layer DL architecture for SWE feature extraction, comprised of the point-wise gated Boltzmann machine (PGBM) and the restricted Boltzmann machine (RBM). The PGBM contains task-relevant and task-irrelevant hidden units, and the task-relevant units are connected to the RBM. Experimental evaluation was performed with five-fold cross validation on a set of 227 SWE images, 135 of benign tumors and 92 of malignant tumors, from 121 patients. The features learned with our DL architecture were compared with the statistical features quantifying image intensity and texture. Results showed that the DL features achieved better classification performance with an accuracy of 93.4%, a sensitivity of 88.6%, a specificity of 97.1%, and an area under the receiver operating characteristic curve of 0.947. The DL-based method integrates feature learning with feature selection on SWE. It may be potentially used in clinical computer-aided diagnosis of breast cancer. Copyright © 2016 Elsevier B.V. All rights reserved.

Summertime Minimum Streamflow Elasticity to Antecendent Winter Precipitation, Peak Snow Water Equivalent and Summertime Evaporative Demand in the Western US Maritime Mountains

NASA Astrophysics Data System (ADS)

Schaperow, J.; Cooper, M. G.; Cooley, S. W.; Alam, S.; Smith, L. C.; Lettenmaier, D. P.

2017-12-01

As climate regimes shift, streamflows and our ability to predict them will change, as well. Elasticity of summer minimum streamflow is estimated for 138 unimpaired headwater river basins across the maritime western US mountains to better understand how climatologic variables and geologic characteristics interact to determine the response of summer low flows to winter precipitation (PPT), spring snow water equivalent (SWE), and summertime potential evapotranspiration (PET). Elasticities are calculated using log log linear regression, and linear reservoir storage coefficients are used to represent basin geology. Storage coefficients are estimated using baseflow recession analysis. On average, SWE, PET, and PPT explain about 1/3 of the summertime low flow variance. Snow-dominated basins with long timescales of baseflow recession are least sensitive to changes in SWE, PPT, and PET, while rainfall-dominated, faster draining basins are most sensitive. There are also implications for the predictability of summer low flows. The R2 between streamflow and SWE drops from 0.62 to 0.47 from snow-dominated to rain-dominated basins, while there is no corresponding increase in R2 between streamflow and PPT.

A 1D-2D coupled SPH-SWE model applied to open channel flow simulations in complicated geometries

NASA Astrophysics Data System (ADS)

Chang, Kao-Hua; Sheu, Tony Wen-Hann; Chang, Tsang-Jung

2018-05-01

In this study, a one- and two-dimensional (1D-2D) coupled model is developed to solve the shallow water equations (SWEs). The solutions are obtained using a Lagrangian meshless method called smoothed particle hydrodynamics (SPH) to simulate shallow water flows in converging, diverging and curved channels. A buffer zone is introduced to exchange information between the 1D and 2D SPH-SWE models. Interpolated water discharge values and water surface levels at the internal boundaries are prescribed as the inflow/outflow boundary conditions in the two SPH-SWE models. In addition, instead of using the SPH summation operator, we directly solve the continuity equation by introducing a diffusive term to suppress oscillations in the predicted water depth. The performance of the two approaches in calculating the water depth is comprehensively compared through a case study of a straight channel. Additionally, three benchmark cases involving converging, diverging and curved channels are adopted to demonstrate the ability of the proposed 1D and 2D coupled SPH-SWE model through comparisons with measured data and predicted mesh-based numerical results. The proposed model provides satisfactory accuracy and guaranteed convergence.

Shear-Wave Elastography: Basic Physics and Musculoskeletal Applications

PubMed Central

Gimber, Lana H.; Becker, Giles W.; Latt, L. Daniel; Klauser, Andrea S.; Melville, David M.; Gao, Liang; Witte, Russell S.

2017-01-01

In the past 2 decades, sonoelastography has been progressively used as a tool to help evaluate soft-tissue elasticity and add to information obtained with conventional gray-scale and Doppler ultrasonographic techniques. Recently introduced on clinical scanners, shear-wave elastography (SWE) is considered to be more objective, quantitative, and reproducible than compression sonoelastography with increasing applications to the musculoskeletal system. SWE uses an acoustic radiation force pulse sequence to generate shear waves, which propagate perpendicular to the ultrasound beam, causing transient displacements. The distribution of shear-wave velocities at each pixel is directly related to the shear modulus, an absolute measure of the tissue’s elastic properties. Shear-wave images are automatically coregistered with standard B-mode images to provide quantitative color elastograms with anatomic specificity. Shear waves propagate faster through stiffer contracted tissue, as well as along the long axis of tendon and muscle. SWE has a promising role in determining the severity of disease and treatment follow-up of various musculoskeletal tissues including tendons, muscles, nerves, and ligaments. This article describes the basic ultrasound physics of SWE and its applications in the evaluation of various traumatic and pathologic conditions of the musculoskeletal system. ©RSNA, 2017 PMID:28493799

Comparing Performance of Combinations of Shear Wave Elastography and B-Mode Ultrasound in Diagnosing Breast Masses: Is It Influenced by Mass Size?

PubMed

Cong, Rui; Li, Jing; Wang, Xuejiao

2017-10-01

We determined the diagnostic performance of combinations of shear wave elastography (SWE) and B-mode ultrasound (US) in differentiating malignant from benign breast masses, and we investigated whether performance is affected by mass size. In this prospective study of 315 consecutive patients with 326 breast masses, US and SWE were performed before biopsy. Masses were categorized into two subgroups on the basis of mass size (≤15 mm and >15 mm), and the optimal thresholds for the SWE parameters were determined for each subgroup using receiver operating characteristic curves. The combination proposed here achieved an area under the receiver operating characteristic curve of 0.943, 95.00% sensitivity and 81.18% specificity, which approximated the diagnostic performance of US alone. The performance of the combinations using the subgroups' thresholds did not differ significantly from those based on the entire study group's thresholds, but the optimal thresholds were higher in the subgroup of larger masses. Further research is needed to determine whether mass size affects the performance of combinations of SWE and US. Copyright © 2017 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Using SWE Standards for Ubiquitous Environmental Sensing: A Performance Analysis

PubMed Central

Tamayo, Alain; Granell, Carlos; Huerta, Joaquín

2012-01-01

Although smartphone applications represent the most typical data consumer tool from the citizen perspective in environmental applications, they can also be used for in-situ data collection and production in varied scenarios, such as geological sciences and biodiversity. The use of standard protocols, such as SWE, to exchange information between smartphones and sensor infrastructures brings benefits such as interoperability and scalability, but their reliance on XML is a potential problem when large volumes of data are transferred, due to limited bandwidth and processing capabilities on mobile phones. In this article we present a performance analysis about the use of SWE standards in smartphone applications to consume and produce environmental sensor data, analysing to what extent the performance problems related to XML can be alleviated by using alternative uncompressed and compressed formats.

A Walk through TRIDEC's intermediate Tsunami Early Warning System for the Turkish and Portuguese NEAMWave12 exercise tsunami scenarios

NASA Astrophysics Data System (ADS)

Hammitzsch, Martin; Lendholt, Matthias; Reißland, Sven; Schulz, Jana

2013-04-01

On November 27-28, 2012, the Kandilli Observatory and Earthquake Research Institute (KOERI) and the Portuguese Institute for the Sea and Atmosphere (IPMA) joined other countries in the North-eastern Atlantic, the Mediterranean and Connected Seas (NEAM) region as participants in an international tsunami response exercise. The exercise, titled NEAMWave12, simulated widespread Tsunami Watch situations throughout the NEAM region. It is the first international exercise as such, in this region, where the UNESCO-IOC ICG/NEAMTWS tsunami warning chain has been tested to a full scale for the first time with different systems. One of the systems is developed in the project Collaborative, Complex, and Critical Decision-Support in Evolving Crises (TRIDEC) and has been validated in this exercise among others by KOERI and IPMA. In TRIDEC new developments in Information and Communication Technology (ICT) are used to extend the existing platform realising a component-based technology framework for building distributed tsunami warning systems for deployment, e.g. in the North-eastern Atlantic, the Mediterranean and Connected Seas (NEAM) region. The TRIDEC system will be implemented in three phases, each with a demonstrator. Successively, the demonstrators are addressing related challenges. The first and second phase system demonstrator, deployed at KOERI's crisis management room and deployed at IPMA has been designed and implemented, firstly, to support plausible scenarios for the Turkish NTWC and for the Portuguese NTWC to demonstrate the treatment of simulated tsunami threats with an essential subset of a NTWC. Secondly, the feasibility and the potentials of the implemented approach are demonstrated covering ICG/NEAMTWS standard operations as well as tsunami detection and alerting functions beyond ICG/NEAMTWS requirements. The demonstrator presented addresses information management and decision-support processes for hypothetical tsunami-related crisis situations in the context of the ICG/NEAMTWS NEAMWave12 exercise for the Turkish and Portuguese tsunami exercise scenarios. Impressions gained with the standards compliant TRIDEC system during the exercise will be reported. The system version presented is based on event-driven architecture (EDA) and service-oriented architecture (SOA) concepts and is making use of relevant standards of the Open Geospatial Consortium (OGC), the World Wide Web Consortium (W3C) and the Organization for the Advancement of Structured Information Standards (OASIS). In this way the system continuously gathers, processes and displays events and data coming from open sensor platforms to enable operators to quickly decide whether an early warning is necessary and to send personalized warning messages to the authorities and the population at large through a wide range of communication channels. The system integrates OGC Sensor Web Enablement (SWE) compliant sensor systems for the rapid detection of hazardous events, like earthquakes, sea level anomalies, ocean floor occurrences, and ground displacements. Using OGC Web Map Service (WMS) and Web Feature Service (WFS) spatial data are utilized to depict the situation picture. The integration of a simulation system to identify affected areas is considered using the OGC Web Processing Service (WPS). Warning messages are compiled and transmitted in the OASIS Common Alerting Protocol (CAP) together with addressing information defined via the OASIS Emergency Data Exchange Language - Distribution Element (EDXL-DE). This demonstration is linked with the talk 'Experiences with TRIDEC's Crisis Management Demonstrator in the Turkish NEAMWave12 exercise tsunami scenario' (EGU2013-2833) given in the session "Architecture of Future Tsunami Warning Systems" (NH5.6).

A Smart Modeling Framework for Integrating BMI-enabled Models as Web Services

NASA Astrophysics Data System (ADS)

Jiang, P.; Elag, M.; Kumar, P.; Peckham, S. D.; Liu, R.; Marini, L.; Hsu, L.

2015-12-01

Serviced-oriented computing provides an opportunity to couple web service models using semantic web technology. Through this approach, models that are exposed as web services can be conserved in their own local environment, thus making it easy for modelers to maintain and update the models. In integrated modeling, the serviced-oriented loose-coupling approach requires (1) a set of models as web services, (2) the model metadata describing the external features of a model (e.g., variable name, unit, computational grid, etc.) and (3) a model integration framework. We present the architecture of coupling web service models that are self-describing by utilizing a smart modeling framework. We expose models that are encapsulated with CSDMS (Community Surface Dynamics Modeling System) Basic Model Interfaces (BMI) as web services. The BMI-enabled models are self-describing by uncovering models' metadata through BMI functions. After a BMI-enabled model is serviced, a client can initialize, execute and retrieve the meta-information of the model by calling its BMI functions over the web. Furthermore, a revised version of EMELI (Peckham, 2015), an Experimental Modeling Environment for Linking and Interoperability, is chosen as the framework for coupling BMI-enabled web service models. EMELI allows users to combine a set of component models into a complex model by standardizing model interface using BMI as well as providing a set of utilities smoothing the integration process (e.g., temporal interpolation). We modify the original EMELI so that the revised modeling framework is able to initialize, execute and find the dependencies of the BMI-enabled web service models. By using the revised EMELI, an example will be presented on integrating a set of topoflow model components that are BMI-enabled and exposed as web services. Reference: Peckham, S.D. (2014) EMELI 1.0: An experimental smart modeling framework for automatic coupling of self-describing models, Proceedings of HIC 2014, 11th International Conf. on Hydroinformatics, New York, NY.

Liver fibrosis detection and staging: a comparative study of T1ρ MR imaging and 2D real-time shear-wave elastography.

PubMed

Li, Ruo-Kun; Ren, Xin-Pin; Yan, Fu-Hua; Qiang, Jin-Wei; Lin, Hui-Min; Tao Wang; Zhao, Hong-Fei; Chen, Wei-Bo

2017-12-02

To compare the results of T1ρ MR imaging and 2D real-time shear-wave elastography (SWE) for liver fibrosis detection and staging. Twenty-nine rabbit models of CCl 4 -induced liver fibrosis were established and six untreated rabbits served as controls. T1ρ MR imaging and 2D real-time SWE examination were performed at 2, 4, 6, 8, 10, and 12 weeks. T1ρ values and liver stiffness (LS) values were measured. Fibrosis was staged according to the METAVIR scoring system. Correlation test was performed among T1ρ values, LS values, and fibrosis stage. Receiver operating characteristic (ROC) analysis was performed for assessing diagnostic performance of T1ρ and SWE in detection of no fibrosis (F0), substantial fibrosis (≥ F2), severe fibrosis (≥ F3), and cirrhosis (F4). There was moderate positive correlation between fibrosis stage and T1ρ values (r = 0.566; 95% CI 0.291-0.754; P < 0.0001), and LS value (r = 0.726; 95% CI 0.521-0.851; P = 0.003). T1ρ values showed moderate positive correlations with LS values [r = 0.693; 95% confidence interval (CI) 0.472-0.832; P < 0.0001]. Areas Under ROC (AUROCs) were 0.861 (95% CI 0.705-0.953) for SWE and 0.856 (95% CI 0.698-0.950) for T1ρ (P = 0.940), 0.906 (95% CI 0.762-0.978) for SWE and 0.849 (95% CI 0.691-0.946) for T1ρ (P = 0.414), 0.870 (95% CI 0.716-0.958) for SWE and 0.799 (95% CI 0.632-0.913) for T1ρ (P = 0.422), and 0.846 (95% CI 0.687-0.944) for SWE and 0.692 (95% CI 0.517-0.835) for T1ρ (P = 0.137), when diagnosing liver fibrosis with ≥ F1, ≥ F2, ≥ F3, and F4, respectively. There was moderate positive correlation between inflammatory activity and T1ρ values (r = 0.520; 95% CI 0.158-0.807; P = 0.013). T1ρ imaging has potential for liver fibrosis detection and staging with good diagnostic capability similar to that of ultrasonography elastography.

Continuous monitoring of a mountain snowpack in the Austrian Alps by above-ground neutron sensing

NASA Astrophysics Data System (ADS)

Schattan, Paul; Baroni, Gabriele; Oswald, Sascha E.; Schöber, Johannes; Fey, Christine; Francke, Till; Huttenlau, Matthias; Achleitner, Stefan

2017-04-01

In alpine catchments the knowledge of the spatially and temporally heterogeneous dynamics of snow accumulation and depletion is crucial for modelling and managing water resources. While snow covered area can be retrieved operationally from remote sensing data, continuous measurements of other snow state variables like snow depth (SD) or snow water equivalent (SWE) remain challenging. Existing methods of retrieving both variables in alpine terrain face severe issues like a lack of spatial representativeness, labour-intensity or discontinuity in time. Recently, promising new measurement techniques combining a larger support with low maintenance cost like above-ground gamma-ray scintillators, GPS interferometric reflectometry or above-ground cosmic-ray neutron sensors (CRNS) have been suggested. While CRNS has proven its potential for monitoring soil moisture in a wide range of environments and applications, the empirical knowledge of using CRNS for snowpack monitoring is still very limited and restricted to shallow snowpacks with rather uniform evolution. The characteristics of an above-ground cosmic-ray neutron sensor (CRNS) were therefore evaluated for monitoring a mountain snowpack in the Austrian Alps (Kaunertal, Tyrol) during three winter seasons. The measurement campaign included a number of measurements during the period from 03/2014 to 06/2016: (i) neutron count measurements by CRNS, (ii) continuous point-scale SD and SWE measurements from an automatic weather station and (iii) 17 Terrestrial Laser Scanning (TLS) with simultaneous SD and SWE surveys. The highest accumulation in terms of SWE was found in 04/2014 with 600 mm. Neutron counts were compared to all available snow data. While previous studies suggested a signal saturation at around 100 mm of SWE, no complete signal saturation was found. A strong non-linear relation was found for both SD and SWE with best fits for spatially distributed TLS based snow data. Initially slightly different shapes were found for accumulation and melting season conditions but this could be resolved by accounting for the limited measurement depth. This depth limit is in the range of 200 mm of SWE for dense snowpacks with high liquid water contents and associated snow density values around 450 kg m-3 and above. Furthermore, the results prove that for medium to high snowpack the inter-annual transferability of the results is very high regardless of pre-snowfall soil moisture conditions. These results underline the high potential of CRNS for closing the gap between point-scale measurements, hydrological models and remote sensing in snow hydrology and alpine terrain.

Analysis and Development of a Web-Enabled Planning and Scheduling Database Application

DTIC Science & Technology

2013-09-01

establishes an entity—relationship diagram for the desired process, constructs an operable database using MySQL , and provides a web- enabled interface for...development, develop, design, process, re- engineering, reengineering, MySQL , structured query language, SQL, myPHPadmin. 15. NUMBER OF PAGES 107 16...relationship diagram for the desired process, constructs an operable database using MySQL , and provides a web-enabled interface for the population of

ESA SSA Programme in support of Space Weather forecasting

NASA Astrophysics Data System (ADS)

Luntama, J.; Glover, A.; Hilgers, A. M.

2010-12-01

In 2009 European Space Agency (ESA) started a new programme called Space Situational Awareness (SSA) Preparatory Programme. The objective of the programme is to support the European independent utilisation of and access to space research or services. This will be performed through providing timely and quality data, information, services and knowledge regarding the environment, the threats and the sustainable exploitation of the outer space surrounding the planet Earth. SSA serves the implementation of the strategic missions of the European Space Policy based on the peaceful uses of the outer space by all states, by supporting the autonomous capacity to securely and safely operate the critical European space infrastructures. The SSA Preparatory Program will establish the initial elements that will eventually lead into the full deployment of the European SSA services. The SWE Segment of the SSA will provide user services related to the monitoring of the Sun, the solar wind, the radiation belts, the magnetosphere and the ionosphere. These services will include near real time information and forecasts about the characteristics of the space environment and predictions of space weather impacts on sensitive spaceborne and ground based infrastructure. The SSA SWE system will also include establishment of a permanent database for analysis, model development and scientific research. These services are will support a wide variety of user domains including spacecraft designers, spacecraft operators, human space flights, users and operators of transionospheric radio links, and space weather research community. The precursor SWE services to be established starting in 2010 will include a selected subset of these services based on pre-existing space weather applications and services in Europe. This paper will present the key characteristics of the SSA SWE system that is currently being designed. The presentation will focus on the system characteristics that support space weather forecasting and the related services. The presentation will show results from the analysis of the existing European assets and the identified development needs in the mid and long term future to ensure forecasting capability for the services requested the by SSA SWE users. The analysis covers the future SSA SWE space segment and the service development needs for the ground segment.

Expanded science and management utllity of SWE and albedo data from the NASA/JPL Airborne Snow Observatory

NASA Astrophysics Data System (ADS)

Painter, T. H.; Deems, J. S.; Marks, D. G.; Hedrick, A. R.; Bormann, K.; Skiles, S. M.; Boardman, J. W.; Graham, C. B.; McGurk, B. J.; Gehrke, F.; Berisford, D. F.; Ferraz, A.; Saatchi, S.; Schimel, D.

2016-12-01

The NASA Airborne Snow Observatory (ASO), an imaging spectrometer and imaging LiDAR system, to quantify snow water equivalent and snow albedo, provide unprecedented knowledge of snow properties, and provide complete, robust inputs to snowmelt runoff models, water management models, and systems of the future. This talk presents results from the fourth year of the ASO program, 2016, and the now four years of data record in the Western United States. Following on the heels of the most intense, sustained drought in California history, 2016 held promise of a large snowfall year due to an intense El Nino anomaly. Ultimately, the year had approximately 85% of average peak SWE. In the Sierra Nevada, ASO measured 10x greater SWE than near peak in the dramatic 2015 drought year, and twice that of the more moderate drought year of 2013. Water managers in the Sierra were using these data regularly and extending the dynamic range of newly established relationships between accumulated runoff (circa April through July runoff) and ASO total basin SWE acquisitions. ASO also participated in the NASA OLYMPEX project by flying the entire snow-covered reghions of the Olympic Peninsula for distributed SWE. These data are now being used to validate snowfall estimates from modeling and accumulation patterns as inferred from the NASA Global Precipitation Measurement mission (GPM). The ASO snow program expanded to acquire data in the McKenzie and Deschutes Rivers of Oregon in participation with university and state/federal agencies; Sagehen and Lee Vining basins in the Sierra Nevada, California; the Reynolds Creek Experimental Watershed in Idaho; and the East River, in the Colorado River Basin. These regions extend the existing program flying the Tuolumne, Merced, Lakes, Rush Creek, and Middle+South Forks of Kings River Basins in the California Sierra Nevada and the Upper Rio Grande, Conejos, and Uncompahgre Basins in the Colorado Rocky Mountains.The ASO SWE and albedo data are now being used to constrain various hydrologic models for water cycle science of varying complexity and expanding empirical and physically-based water management models.

SU-E-J-76: Incorporation of Ultrasound Elastography in Target Volume Delineation for Partial Breast Radiotherapy Planning: A Comparative Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Juneja, P; Harris, E; Bamber, J

2014-06-01

Purpose: There is substantial observer variability in the delineation of target volumes for post-surgical partial breast radiotherapy because the tumour bed has poor x-ray contrast. This variability may result in substantial variations in planned dose distribution. Ultrasound elastography (USE) has an ability to detect mechanical discontinuities and therefore, the potential to image the scar and distortion in breast tissue architecture. The goal of this study was to compare USE techniques: strain elastography (SE), shear wave elastography (SWE) and acoustic radiation force impulse (ARFI) imaging using phantoms that simulate features of the tumour bed, for the purpose of incorporating USE inmore » breast radiotherapy planning. Methods: Three gelatine-based phantoms (10% w/v) containing: a stiff inclusion (gelatine 16% w/v) with adhered boundaries, a stiff inclusion (gelatine 16% w/v) with mobile boundaries and fluid cavity inclusion (to mimic seroma), were constructed and used to investigate the USE techniques. The accuracy of the elastography techniques was quantified by comparing the imaged inclusion with the modelled ground-truth using the Dice similarity coefficient (DSC). For two regions of interest (ROI), the DSC measures their spatial overlap. Ground-truth ROIs were modelled using geometrical measurements from B-mode images. Results: The phantoms simulating stiff scar tissue with adhered and mobile boundaries and seroma were successfully developed and imaged using SE and SWE. The edges of the stiff inclusions were more clearly visible in SE than in SWE. Subsequently, for all these phantoms the measured DSCs were found to be higher for SE (DSCs: 0.91–0.97) than SWE (DSCs: 0.68–0.79) with an average relative difference of 23%. In the case of seroma phantom, DSC values for SE and SWE were similar. Conclusion: This study presents a first attempt to identify the most suitable elastography technique for use in breast radiotherapy planning. Further analysis will include comparison of ARFI with SE and SWE. This work is supported by the EPSRC Platform Grant, reference number EP/H046526/1.« less

Estimating changing snow water resources over the Himalaya from remote sensing at the weekly scale

NASA Astrophysics Data System (ADS)

Ackroyd, C.; Skiles, M.

2017-12-01

Water resources in South Asia are critically dependent on High Mountain Asia, namely as the headwaters for the Indus, Ganges, and Brahmaputra River Basins. For water and economic security it is important to understand how the natural snow water reservoir is changing at a time scale that is relevant for water management, which can most feasibly be achieved across this vast and complex landscape through remote sensing. Here we present results from recent efforts to develop an optimal method that combines MODIS fractional snow covered area (MODSCAG) with retrievals of SWE from space borne microwave data (AMSR2) over the Hindu Kush Himalaya, which is further combined with MODIS dust radiative forcing (MODDRFS) to monitor rate of snow darkening, and provide a simple snowmelt metric that informs the contribution to melt by light absorbing particulates like dust and black carbon. For data consistency we are using 8 day composites of all products, and therefore the difference from time step to time step is a weekly, first order approximation, of the amount of SWE lost or gained from the region. MODIS retrievals are valuable for studying the hydrology of South Asia because there are mature sub kilometer scale products for the reflectance and fractional extent of the snow cover, the melt from which is mainly controlled by net solar radiation. The value of retrievals of SWE from space borne microwave data is less well established due to numerous sources of error (e.g. grain size and density, forest obscuration, penetration depth reduction, saturation) and the coarse 25 km spatial scale, which cannot capture the variation in SWE at the scale of individual mountain massifs. Despite these limitations it is currently the only available satellite based SWE product. This research effort is part of a larger NASA-SERVIR project that aims to join SWE estimates from MODIS and AMSR2, subsurface water storage variations from GRACE, and the RAPID river routing model to assess water resource variability at the management scale in South Asia and then transfer knowledge, and share developed tools and datasets, to local stakeholders.

Shear wave elastography (SWE) of the spleen in patients with hepatitis B and C but without significant liver fibrosis

PubMed Central

Pawluś, Aleksander; Inglot, Marcin; Szymańska, Kinga; Inglot, Małgorzata; Patyk, Mateusz; Słonina, Joanna; Caseiro-Alves, Filipe; Janczak, Dariusz; Zaleska-Dorobisz, Urszula

2016-01-01

Objective: The aim of the study was to compare the elasticity of the spleen in patients with hepatitis B and C but without liver fibrosis with that of healthy subjects using a shear wave elastography (SWE) examination. Methods: Between December 2014 and December 2015, 35 patients with hepatitis B virus (HBV) infections and 45 patients with (hepatitis C virus) HCV infections and liver stiffness below 7.1 kPa were included in the study. The control group was composed of 53 healthy volunteers without any chronic liver disease, with no abnormal findings in their ultrasound examinations and with an SWE of the liver below 6.5 kPa. The SWE measurements were a part of routine ultrasound abdominal examinations. The examinations were performed using an Aixplorer device by two radiologists with at least 6 years' experience. To compare spleen stiffness between the groups, the Mann–Whitney U-test was applied. To analyze the dependency between liver and spleen elasticity, Spearman's rank correlation coefficient was calculated. Results: A total of 133 SWE findings were analyzed. Stiffness of the spleen was significantly higher in patients with HBV and HCV but without significant liver fibrosis than it was in the healthy controls (p = 0.0018 and 0.0000, respectively). This correlation was also present in patients with liver stiffness below 6.5 kPa (p = 0.0041 and 0.0000, respectively). Analysis revealed no significant correlation between liver and spleen stiffness in patients with hepatitis B and C and without significant fibrosis (p = 0.3216 and 0.0626, respectively). Conclusion: Patients with hepatitis B and C but without significant liver fibrosis have stiffer spleens than healthy controls. There is no dependency between liver and spleen elasticity in patients without significant fibrosis. Advances in knowledge: The SWE examination might be an important tool and could be used in addition to conventional imaging. Our study may become a starting point in further investigations into the role of the spleen in HCV and HBV infections and perhaps into introducing spleen elastography into diagnostic and follow-up procedures. PMID:27529729

Shear wave elastography (SWE) of the spleen in patients with hepatitis B and C but without significant liver fibrosis.

PubMed

Pawluś, Aleksander; Inglot, Marcin; Chabowski, Mariusz; Szymańska, Kinga; Inglot, Małgorzata; Patyk, Mateusz; Słonina, Joanna; Caseiro-Alves, Filipe; Janczak, Dariusz; Zaleska-Dorobisz, Urszula

2016-10-01

The aim of the study was to compare the elasticity of the spleen in patients with hepatitis B and C but without liver fibrosis with that of healthy subjects using a shear wave elastography (SWE) examination. Between December 2014 and December 2015, 35 patients with hepatitis B virus (HBV) infections and 45 patients with (hepatitis C virus) HCV infections and liver stiffness below 7.1 kPa were included in the study. The control group was composed of 53 healthy volunteers without any chronic liver disease, with no abnormal findings in their ultrasound examinations and with an SWE of the liver below 6.5 kPa. The SWE measurements were a part of routine ultrasound abdominal examinations. The examinations were performed using an Aixplorer device by two radiologists with at least 6 years' experience. To compare spleen stiffness between the groups, the Mann-Whitney U-test was applied. To analyze the dependency between liver and spleen elasticity, Spearman's rank correlation coefficient was calculated. A total of 133 SWE findings were analyzed. Stiffness of the spleen was significantly higher in patients with HBV and HCV but without significant liver fibrosis than it was in the healthy controls (p = 0.0018 and 0.0000, respectively). This correlation was also present in patients with liver stiffness below 6.5 kPa (p = 0.0041 and 0.0000, respectively). Analysis revealed no significant correlation between liver and spleen stiffness in patients with hepatitis B and C and without significant fibrosis (p = 0.3216 and 0.0626, respectively). Patients with hepatitis B and C but without significant liver fibrosis have stiffer spleens than healthy controls. There is no dependency between liver and spleen elasticity in patients without significant fibrosis. The SWE examination might be an important tool and could be used in addition to conventional imaging. Our study may become a starting point in further investigations into the role of the spleen in HCV and HBV infections and perhaps into introducing spleen elastography into diagnostic and follow-up procedures.

Consistent data recording across a health system and web-enablement allow service quality comparisons: online data for commissioning dermatology services.

PubMed

Dmitrieva, Olga; Michalakidis, Georgios; Mason, Aaron; Jones, Simon; Chan, Tom; de Lusignan, Simon

2012-01-01

A new distributed model of health care management is being introduced in England. Family practitioners have new responsibilities for the management of health care budgets and commissioning of services. There are national datasets available about health care providers and the geographical areas they serve. These data could be better used to assist the family practitioner turned health service commissioners. Unfortunately these data are not in a form that is readily usable by these fledgling family commissioning groups. We therefore Web enabled all the national hospital dermatology treatment data in England combining it with locality data to provide a smart commissioning tool for local communities. We used open-source software including the Ruby on Rails Web framework and MySQL. The system has a Web front-end, which uses hypertext markup language cascading style sheets (HTML/CSS) and JavaScript to deliver and present data provided by the database. A combination of advanced caching and schema structures allows for faster data retrieval on every execution. The system provides an intuitive environment for data analysis and processing across a large health system dataset. Web-enablement has enabled data about in patients, day cases and outpatients to be readily grouped, viewed, and linked to other data. The combination of web-enablement, consistent data collection from all providers; readily available locality data; and a registration based primary system enables the creation of data, which can be used to commission dermatology services in small areas. Standardized datasets collected across large health enterprises when web enabled can readily benchmark local services and inform commissioning decisions.

NeXOS, developing and evaluating a new generation of insitu ocean observation systems.

NASA Astrophysics Data System (ADS)

Delory, Eric; del Rio, Joaquin; Golmen, Lars; Roar Hareide, Nils; Pearlman, Jay; Rolin, Jean-Francois; Waldmann, Christoph; Zielinski, Oliver

2017-04-01

Ocean biological, chemical or physical processes occur over widely varying scales in space and time: from micro- to kilometer scales, from less than seconds to centuries. While space systems supply important data and information, insitu data is necessary for comprehensive modeling and forecasting of ocean dynamics. Yet, collection of in-situ observation on these scales is inherently challenging and remains generally difficult and costly in time and resources. This paper address the innovations and significant developments for a new generation of insitu sensors in FP7 European Union project "Next generation, Cost- effective, Compact, Multifunctional Web Enabled Ocean Sensor Systems Empowering Marine, Maritime and Fisheries Management" or "NeXOS" for short. Optical and acoustics sensors are the focus of NeXOS but NeXOS moves beyond just sensors as systems that simultaneously address multiple objectives and applications are becoming increasingly important. Thus NeXOS takes a perspective of both sensors and sensor systems with significant advantages over existing observing capabilities via the implementation of innovations such as multiplatform integration, greater reliability through better antifouling management and greater sensor and data interoperability through use of OGC standards. This presentation will address the sensor system development and field-testing of the new NeXOS sensor systems. This is being done on multiple platforms including profiling floats, gliders, ships, buoys and subsea stations. The implementation of a data system based on SWE and PUCK furthers interoperability across measurements and platforms. This presentation will review the sensor system capabilities, the status of field tests and recommendations for long-term ocean monitoring.

Cue-based assertion classification for Swedish clinical text – developing a lexicon for pyConTextSwe

PubMed Central

Velupillai, Sumithra; Skeppstedt, Maria; Kvist, Maria; Mowery, Danielle; Chapman, Brian E.; Dalianis, Hercules; Chapman, Wendy W.

2014-01-01

Objective The ability of a cue-based system to accurately assert whether a disorder is affirmed, negated, or uncertain is dependent, in part, on its cue lexicon. In this paper, we continue our study of porting an assertion system (pyConTextNLP) from English to Swedish (pyConTextSwe) by creating an optimized assertion lexicon for clinical Swedish. Methods and material We integrated cues from four external lexicons, along with generated inflections and combinations. We used subsets of a clinical corpus in Swedish. We applied four assertion classes (definite existence, probable existence, probable negated existence and definite negated existence) and two binary classes (existence yes/no and uncertainty yes/no) to pyConTextSwe. We compared pyConTextSwe’s performance with and without the added cues on a development set, and improved the lexicon further after an error analysis. On a separate evaluation set, we calculated the system’s final performance. Results Following integration steps, we added 454 cues to pyConTextSwe. The optimized lexicon developed after an error analysis resulted in statistically significant improvements on the development set (83% F-score, overall). The system’s final F-scores on an evaluation set were 81% (overall). For the individual assertion classes, F-score results were 88% (definite existence), 81% (probable existence), 55% (probable negated existence), and 63% (definite negated existence). For the binary classifications existence yes/no and uncertainty yes/no, final system performance was 97%/87% and 78%/86% F-score, respectively. Conclusions We have successfully ported pyConTextNLP to Swedish (pyConTextSwe). We have created an extensive and useful assertion lexicon for Swedish clinical text, which could form a valuable resource for similar studies, and which is publicly available. PMID:24556644

Measurements of renal shear wave velocities in chronic kidney disease patients.

PubMed

Sasaki, Yutaka; Hirooka, Yoshiki; Kawashima, Hiroki; Ishikawa, Takuya; Takeshita, Kyosuke; Goto, Hidemi

2018-07-01

Background Chronic kidney disease (CKD) patients have advanced glomerulosclerosis and renal interstitial fibrosis. Shear wave elastography (SWE) is useful to diagnose liver fibrosis. However, there are few data available regarding evaluation of kidney function on the use of SWE. Purpose To assess the utility of SWE by evaluating the correlation between renal function and renal elasticity using SWE. Material and Methods A total of 187 participants who had available serum creatinine levels and also underwent SWE of the kidney using a transabdominal ultrasonography were recruited at Nagoya University Hospital. We measured the depth of the shear wave (SW) in the right and left kidneys and calculated the measurement success rates. The glomerular filtration rate (GFR) classification and shear wave value (SWV) were compared. Results The success rates of the right and left kidneys were 93.6% and 71.6%, respectively. Based on these results, the correlation between GFR classification and SWV were analyzed in only the right kidneys because the success rates and the number of enrolled patients were low for the left kidney. There were significant differences found between G1 and G3a, G2 and G3a, G3a and G3b, G3a and G4, and G3a and G5. SWV significantly negatively and positively correlated with the G2-G3a and G3a-G3b classifications. Conclusion There is no correlation between renal function and SW. However, we can diagnose the progression to the CKD stages G3a and G3b by observing the changes over time using the SWV.

An in silico framework to analyze the anisotropic shear wave mechanics in cardiac shear wave elastography

NASA Astrophysics Data System (ADS)

Caenen, Annette; Pernot, Mathieu; Peirlinck, Mathias; Mertens, Luc; Swillens, Abigail; Segers, Patrick

2018-04-01

Shear wave elastography (SWE) is a potential tool to non-invasively assess cardiac muscle stiffness. This study focused on the effect of the orthotropic material properties and mechanical loading on the performance of cardiac SWE, as it is known that these factors contribute to complex 3D anisotropic shear wave propagation. To investigate the specific impact of these complexities, we constructed a finite element model with an orthotropic material law subjected to different uniaxial stretches to simulate SWE in the stressed cardiac wall. Group and phase speed were analyzed in function of tissue thickness and virtual probe rotation angle. Tissue stretching increased the group and phase speed of the simulated shear wave, especially in the direction of the muscle fiber. As the model provided access to the true fiber orientation and material properties, we assessed the accuracy of two fiber orientation extraction methods based on SWE. We found a higher accuracy (but lower robustness) when extracting fiber orientations based on the location of maximal shear wave speed instead of the angle of the major axis of the ellipsoidal group speed surface. Both methods had a comparable performance for the center region of the cardiac wall, and performed less well towards the edges. Lastly, we also assessed the (theoretical) impact of pathology on shear wave physics and characterization in the model. It was found that SWE was able to detect changes in fiber orientation and material characteristics, potentially associated with cardiac pathologies such as myocardial fibrosis. Furthermore, the model showed clearly altered shear wave patterns for the fibrotic myocardium compared to the healthy myocardium, which forms an initial but promising outcome of this modeling study.

Evaluation of the Snow Simulations from the Community Land Model, Version 4 (CLM4)

NASA Technical Reports Server (NTRS)

Toure, Ally M.; Rodell, Matthew; Yang, Zong-Liang; Beaudoing, Hiroko; Kim, Edward; Zhang, Yongfei; Kwon, Yonghwan

2015-01-01

This paper evaluates the simulation of snow by the Community Land Model, version 4 (CLM4), the land model component of the Community Earth System Model, version 1.0.4 (CESM1.0.4). CLM4 was run in an offline mode forced with the corrected land-only replay of the Modern-Era Retrospective Analysis for Research and Applications (MERRA-Land) and the output was evaluated for the period from January 2001 to January 2011 over the Northern Hemisphere poleward of 30 deg N. Simulated snow-cover fraction (SCF), snow depth, and snow water equivalent (SWE) were compared against a set of observations including the Moderate Resolution Imaging Spectroradiometer (MODIS) SCF, the Interactive Multisensor Snow and Ice Mapping System (IMS) snow cover, the Canadian Meteorological Centre (CMC) daily snow analysis products, snow depth from the National Weather Service Cooperative Observer (COOP) program, and Snowpack Telemetry (SNOTEL) SWE observations. CLM4 SCF was converted into snow-cover extent (SCE) to compare with MODIS SCE. It showed good agreement, with a correlation coefficient of 0.91 and an average bias of -1.54 x 10(exp 2) sq km. Overall, CLM4 agreed well with IMS snow cover, with the percentage of correctly modeled snow-no snow being 94%. CLM4 snow depth and SWE agreed reasonably well with the CMC product, with the average bias (RMSE) of snow depth and SWE being 0.044m (0.19 m) and -0.010m (0.04 m), respectively. CLM4 underestimated SNOTEL SWE and COOP snow depth. This study demonstrates the need to improve the CLM4 snow estimates and constitutes a benchmark against which improvement of the model through data assimilation can be measured.

A Machine-Learning Algorithm Toward Color Analysis for Chronic Liver Disease Classification, Employing Ultrasound Shear Wave Elastography.

PubMed

Gatos, Ilias; Tsantis, Stavros; Spiliopoulos, Stavros; Karnabatidis, Dimitris; Theotokas, Ioannis; Zoumpoulis, Pavlos; Loupas, Thanasis; Hazle, John D; Kagadis, George C

2017-09-01

The purpose of the present study was to employ a computer-aided diagnosis system that classifies chronic liver disease (CLD) using ultrasound shear wave elastography (SWE) imaging, with a stiffness value-clustering and machine-learning algorithm. A clinical data set of 126 patients (56 healthy controls, 70 with CLD) was analyzed. First, an RGB-to-stiffness inverse mapping technique was employed. A five-cluster segmentation was then performed associating corresponding different-color regions with certain stiffness value ranges acquired from the SWE manufacturer-provided color bar. Subsequently, 35 features (7 for each cluster), indicative of physical characteristics existing within the SWE image, were extracted. A stepwise regression analysis toward feature reduction was used to derive a reduced feature subset that was fed into the support vector machine classification algorithm to classify CLD from healthy cases. The highest accuracy in classification of healthy to CLD subject discrimination from the support vector machine model was 87.3% with sensitivity and specificity values of 93.5% and 81.2%, respectively. Receiver operating characteristic curve analysis gave an area under the curve value of 0.87 (confidence interval: 0.77-0.92). A machine-learning algorithm that quantifies color information in terms of stiffness values from SWE images and discriminates CLD from healthy cases is introduced. New objective parameters and criteria for CLD diagnosis employing SWE images provided by the present study can be considered an important step toward color-based interpretation, and could assist radiologists' diagnostic performance on a daily basis after being installed in a PC and employed retrospectively, immediately after the examination. Copyright © 2017 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Mid-life environmental enrichment increases synaptic density in CA1 in a mouse model of Aβ-associated pathology and positively influences synaptic and cognitive health in healthy ageing.

PubMed

Stuart, Kimberley E; King, Anna E; Fernandez-Martos, Carmen M; Dittmann, Justin; Summers, Mathew J; Vickers, James C

2017-06-01

Early-life cognitive enrichment may reduce the risk of experiencing cognitive deterioration and dementia in later-life. However, an intervention to prevent or delay dementia is likely to be taken up in mid to later-life. Hence, we investigated the effects of environmental enrichment in wildtype mice and in a mouse model of Aβ neuropathology (APP SWE /PS1 dE9 ) from 6 months of age. After 6 months of housing in standard laboratory cages, APP SWE /PS1 dE9 (n = 27) and healthy wildtype (n = 21) mice were randomly assigned to either enriched or standard housing. At 12 months of age, wildtype mice showed altered synaptic protein levels and relatively superior cognitive performance afforded by environmental enrichment. Environmental enrichment was not associated with alterations to Aβ plaque pathology in the neocortex or hippocampus of APP SWE /PS1 dE9 mice. However, a significant increase in synaptophysin immunolabeled puncta in the hippocampal subregion, CA1, in APP SWE /PS1 dE9 mice was detected, with no significant synaptic density changes observed in CA3, or the Fr2 region of the prefrontal cortex. Moreover, a significant increase in hippocampal BDNF was detected in APP SWE /PS1 dE9 mice exposed to EE, however, no changes were detected in neocortex or between Wt animals. These results demonstrate that mid to later-life cognitive enrichment has the potential to promote synaptic and cognitive health in ageing, and to enhance compensatory capacity for synaptic connectivity in pathological ageing associated with Aβ deposition. © 2017 Wiley Periodicals, Inc.

Does Lesion Size Affect the Value of Shear Wave Elastography for Differentiating Between Benign and Malignant Thyroid Nodules?

PubMed

Wang, Fen; Chang, Cai; Chen, Min; Gao, Yi; Chen, Ya-Ling; Zhou, Shi-Chong; Li, Jia-Wei; Zhi, Wen-Xiang

2018-03-01

We aimed to investigate the diagnostic performance of shear wave elastography (SWE) combined with conventional ultrasonography (US) for differentiating between benign and malignant thyroid nodules of different sizes. A total of 445 thyroid nodules from 445 patients were divided into 3 groups based on diameter (group 1, ≤ 10 mm; group 2, 10-20 mm; and group 3, > 20 mm). The mean elasticity index of the whole lesion was automatically calculated, and the threshold for differentiation between benign and malignant nodules was constructed by a receiver operating characteristic curve analysis. Diagnostic performances of conventional US and SWE were compared by using pathologic results as reference standards. The mean elasticity was significantly higher in malignant versus benign nodules for all size groups. The differences in mean elasticity in the size groups were not statistically significant for malignant or benign nodules. The specificity of US combined with SWE for group 1 was significantly higher than that for groups 2 and 3 (77.8% versus 62.9% and 53.3%; P < .05), and compared with group 1, the sensitivity was significantly higher for groups 2 and 3 (92.4% and 94.3% versus 80.7%; P < .05). When SWE was added, the specificity increased and the sensitivity and diagnostic accuracy decreased for group 1, and the sensitivity increased and the specificity decreased for groups 2 and 3; however, the differences were not significant. Combined with SWE, US yielded higher specificity for nodules of 10 mm and smaller and higher sensitivity for nodules larger than 10 mm. © 2017 by the American Institute of Ultrasound in Medicine.

Liver Stiffness Measured by Two-Dimensional Shear-Wave Elastography: Prognostic Value after Radiofrequency Ablation for Hepatocellular Carcinoma.

PubMed

Lee, Dong Ho; Lee, Jeong Min; Yoon, Jung-Hwan; Kim, Yoon Jun; Lee, Jeong-Hoon; Yu, Su Jong; Han, Joon Koo

2018-03-01

To evaluate the prognostic value of liver stiffness (LS) measured using two-dimensional (2D) shear-wave elastography (SWE) in patients with hepatocellular carcinoma (HCC) treated by radiofrequency ablation (RFA). The Institutional Review Board approved this retrospective study and informed consent was obtained from all patients. A total of 134 patients with up to 3 HCCs ≤5 cm who had undergone pre-procedural 2D-SWE prior to RFA treatment between January 2012 and December 2013 were enrolled. LS values were measured using real-time 2D-SWE before RFA on the procedural day. After a mean follow-up of 33.8 ± 9.9 months, we analyzed the overall survival after RFA using the Kaplan-Meier method and Cox proportional hazard regression model. The optimal cutoff LS value to predict overall survival was determined using the minimal p value approach. During the follow-up period, 22 patients died, and the estimated 1- and 3-year overall survival rates were 96.4 and 85.8%, respectively. LS measured by 2D-SWE was found to be a significant predictive factor for overall survival after RFA of HCCs, as was the presence of extrahepatic metastases. As for the optimal cutoff LS value for the prediction of overall survival, it was determined to be 13.3 kPa. In our study, 71 patients had LS values ≥13.3 kPa, and the estimated 3-year overall survival was 76.8% compared to 96.3% in 63 patients with LS values <13.3 kPa. This difference was statistically significant (hazard ratio = 4.30 [1.26-14.7]; p = 0.020). LS values measured by 2D-SWE was a significant predictive factor for overall survival after RFA for HCC.

Role of Endoplasmic Reticulum Stress in Learning and Memory Impairment and Alzheimer's Disease-Like Neuropathology in the PS19 and APPSwe Mouse Models of Tauopathy and Amyloidosis.

PubMed

Briggs, Denise Isabelle; Defensor, Erwin; Memar Ardestani, Pooneh; Yi, Bitna; Halpain, Michelle; Seabrook, Guy; Shamloo, Mehrdad

2017-01-01

Emerging evidence suggests that endoplasmic reticulum (ER) stress may be involved in the pathogenesis of Alzheimer's disease (AD). Recently, pharmacological modulation of the eukaryotic translation initiation factor-2 (eIF2α) pathway was achieved using an integrated stress response inhibitor (ISRIB). While members of this signaling cascade have been suggested as potential therapeutic targets for neurodegeneration, the biological significance of this pathway has not been comprehensively assessed in animal models of AD. The present study investigated the ER stress pathway and its long-term modulation utilizing in vitro and in vivo experimental models of tauopathy (MAPT P301S)PS19 and amyloidosis (APP Swe ). We report that thapsigargin induces activating transcription factor-4 (ATF4) in primary cortical neurons (PCNs) derived from rat and APP Swe nontransgenic (nTg) and transgenic (Tg) mice. ISRIB mitigated the induction of ATF4 in PCNs generated from wild-type (WT) but not APP Swe mice despite partially restoring thapsigargin-induced translational repression in nTg PCNs. In vivo , C57BL/6J and PS19 mice received prolonged, once-daily administration of ISRIB. While the compound was well tolerated by PS19 and C57BL/6J mice, APP Swe mice treated per this schedule displayed significant mortality. Thus, the dose was reduced and administered only on behavioral test days. ISRIB did not improve learning and memory function in APP Swe Tg mice. While ISRIB did not reduce tau-related neuropathology in PS19 Tg mice, no evidence of ER stress-related dysfunction was observed in either of these Tg models. Taken together, the significance of ER stress and the relevance of these models to the etiology of AD require further investigation.

A model for the spatial distribution of snow water equivalent parameterized from the spatial variability of precipitation

NASA Astrophysics Data System (ADS)

Skaugen, Thomas; Weltzien, Ingunn H.

2016-09-01

Snow is an important and complicated element in hydrological modelling. The traditional catchment hydrological model with its many free calibration parameters, also in snow sub-models, is not a well-suited tool for predicting conditions for which it has not been calibrated. Such conditions include prediction in ungauged basins and assessing hydrological effects of climate change. In this study, a new model for the spatial distribution of snow water equivalent (SWE), parameterized solely from observed spatial variability of precipitation, is compared with the current snow distribution model used in the operational flood forecasting models in Norway. The former model uses a dynamic gamma distribution and is called Snow Distribution_Gamma, (SD_G), whereas the latter model has a fixed, calibrated coefficient of variation, which parameterizes a log-normal model for snow distribution and is called Snow Distribution_Log-Normal (SD_LN). The two models are implemented in the parameter parsimonious rainfall-runoff model Distance Distribution Dynamics (DDD), and their capability for predicting runoff, SWE and snow-covered area (SCA) is tested and compared for 71 Norwegian catchments. The calibration period is 1985-2000 and validation period is 2000-2014. Results show that SDG better simulates SCA when compared with MODIS satellite-derived snow cover. In addition, SWE is simulated more realistically in that seasonal snow is melted out and the building up of "snow towers" and giving spurious positive trends in SWE, typical for SD_LN, is prevented. The precision of runoff simulations using SDG is slightly inferior, with a reduction in Nash-Sutcliffe and Kling-Gupta efficiency criterion of 0.01, but it is shown that the high precision in runoff prediction using SD_LN is accompanied with erroneous simulations of SWE.

A new method of measuring the stiffness of corpus cavernosum penis with ShearWave™ Elastography

PubMed Central

Zhang, J-J; Qiao, X-H; Gao, F; Li, F; Bai, M; Zhang, H-P; Liu, Y; Du, L-F

2015-01-01

Objective: To evaluate the feasibility of measuring the stiffness of corpus cavernosum penis (CCP) with ShearWave™ Elastography (SWE; SuperSonic Imagine, Aix-en-Provence, France). Methods: 40 healthy volunteers with ages ranging from 19 to 81 years (mean, 36 years; standard deviation, 17 years) were selected in this study. The ultrafast ultrasound device Aixplorer® (SuperSonic Imagine) was used for the research and the probe selected was SuperLinear™ SL15-4 (SuperSonic Imagine). The shear wave stiffness (SWS) of CCP was measured using SWE images. The measurement indexes of SWS included (1) SWS of CCP measured in the transverse section (SWS-T), (2) SWS of CCP measured in the longitudinal section (SWS-L) and (3) mean of SWS-T and SWS-L (SWS-M). The interval between hormone test and SWE examination of each subject was less than 7 days. The paired t-test was used to analyse the differences between SWS-T and SWS-L. The Pearson correlation was used to analyse the correlation of SWS of CCP with age as well as with sex hormone levels. Results: There was no significant difference between SWS-T and SWS-L (p > 0.05). SWS (SWS-T, SWS-L, SWS-M) was negatively correlated with age and oestradiol value, and SWS (SWS-T, SWS-L, SWS-M) was positively correlated with testosterone value. Conclusion: SWE could serve as a new non-invasive method of evaluating the stiffness of CCP. Advances in knowledge: It is the first time that we have discussed the feasibility of measuring the stiffness of CCP with SWE and analysed the correlation of SWS of CCP with age as well as with sex hormone levels. PMID:25694260

A new method of measuring the stiffness of corpus cavernosum penis with ShearWave™ Elastography.

PubMed

Zhang, J-J; Qiao, X-H; Gao, F; Li, F; Bai, M; Zhang, H-P; Liu, Y; Du, L-F; Xing, J-F

2015-04-01

To evaluate the feasibility of measuring the stiffness of corpus cavernosum penis (CCP) with ShearWave™ Elastography (SWE; SuperSonic Imagine, Aix-en-Provence, France). 40 healthy volunteers with ages ranging from 19 to 81 years (mean, 36 years; standard deviation, 17 years) were selected in this study. The ultrafast ultrasound device Aixplorer(®) (SuperSonic Imagine) was used for the research and the probe selected was SuperLinear™ SL15-4 (SuperSonic Imagine). The shear wave stiffness (SWS) of CCP was measured using SWE images. The measurement indexes of SWS included (1) SWS of CCP measured in the transverse section (SWS-T), (2) SWS of CCP measured in the longitudinal section (SWS-L) and (3) mean of SWS-T and SWS-L (SWS-M). The interval between hormone test and SWE examination of each subject was less than 7 days. The paired t-test was used to analyse the differences between SWS-T and SWS-L. The Pearson correlation was used to analyse the correlation of SWS of CCP with age as well as with sex hormone levels. There was no significant difference between SWS-T and SWS-L (p > 0.05). SWS (SWS-T, SWS-L, SWS-M) was negatively correlated with age and oestradiol value, and SWS (SWS-T, SWS-L, SWS-M) was positively correlated with testosterone value. SWE could serve as a new non-invasive method of evaluating the stiffness of CCP. It is the first time that we have discussed the feasibility of measuring the stiffness of CCP with SWE and analysed the correlation of SWS of CCP with age as well as with sex hormone levels.

Improving simulations of snow water equivalent and total water storage changes over the Upper Yangtze River basin using multi-source remote sensing data

NASA Astrophysics Data System (ADS)

Han, P.; Long, D.

2017-12-01

Snow water equivalent (SWE) and total water storage (TWS) changes are important hydrological state variables over cryospheric regions, such as China's Upper Yangtze River (UYR) basin. Accurate simulation of these two state variables plays a critical role in understanding hydrological processes over this region and, in turn, benefits water resource management, hydropower development, and ecological integrity over the lower reaches of the Yangtze River, one of the largest rivers globally. In this study, an improved CREST model coupled with a snow and glacier melting module was used to simulate SWE and TWS changes over the UYR, and to quantify contributions of snow and glacier meltwater to the total runoff. Forcing, calibration, and validation data are mainly from multi-source remote sensing observations, including satellite-based precipitation estimates, passive microwave remote sensing-based SWE, and GRACE-derived TWS changes, along with streamflow measurements at the Zhimenda gauging station. Results show that multi-source remote sensing information can be extremely valuable in model forcing, calibration, and validation over the poorly gauged region. The simulated SWE and TWS changes and the observed counterparts are highly consistent, showing NSE coefficients higher than 0.8. The results also show that the contributions of snow and glacier meltwater to the total runoff are 8% and 6%, respectively, during the period 2003‒2014, which is an important source of runoff. Moreover, from this study, the TWS is found to increase at a rate of 5 mm/a ( 0.72 Gt/a) for the period 2003‒2014. The snow melting module may overestimate SWE for high precipitation events and was improved in this study. Key words: CREST model; Remote Sensing; Melting model; Source Region of the Yangtze River

Modeling and measuring snow for assessing climate change impacts in Glacier National Park, Montana

USGS Publications Warehouse

Fagre, Daniel B.; Selkowitz, David J.; Reardon, Blase; Holzer, Karen; Mckeon, Lisa L.

2002-01-01

A 12-year program of global change research at Glacier National Park by the U.S. Geological Survey and numerous collaborators has made progress in quantifying the role of snow as a driver of mountain ecosystem processes. Spatially extensive snow surveys during the annual accumulation/ablation cycle covered two mountain watersheds and approximately 1,000 km2 . Over 7,000 snow depth and snow water equivalent (SWE) measurements have been made through spring 2002. These augment two SNOTEL sites, 9 NRCS snow courses, and approximately 150 snow pit analyses. Snow data were used to establish spatially-explicit interannual variability in snowpack SWE. East of the Continental Divide, snowpack SWE was lower but also less variable than west of the Divide. Analysis of snowpacks suggest downward trends in SWE, a reduction in snow cover duration, and earlier melt-out dates during the past 52 years. Concurrently, high elevation forests and treelines have responded with increased growth. However, the 80 year record of snow from 3 NRCS snow courses reflects a strong influence from the Pacific Decadal Oscillation, resulting in 20-30 year phases of greater or lesser mean SWE. Coupled with the fine-resolution spatial snow data from the two watersheds, the ecological consequences of changes in snowpack can be empirically assessed at a habitat patch scale. This will be required because snow distribution models have had varied success in simulating snowpack accumulation/ablation dynamics in these mountain watersheds, ranging from R2=0.38 for individual south-facing forested snow survey routes to R2=0.95 when aggregated to the watershed scale. Key ecological responses to snowpack changes occur below the watershed scale, such as snow-mediated expansion of forest into subalpine meadows, making continued spatially-explicit snow surveys a necessity. 

Processes regulating watershed chemical export during snowmelt, fraser experimental forest, Colorado

USGS Publications Warehouse

Stottlemyer, R.

2001-01-01

In the Central Rocky Mountains, snowfall dominates precipitation. Airborne contaminants retained in the snowpack can affect high elevation surface water chemistry during snowmelt. At the Fraser Experimental Forest (FEF), located west of the Continental Divide in Central Colorado, snowmelt dominates the annual hydrograph, and accounts for >95% of annual stream water discharge. During the winters of 1989-1993, we measured precipitation inputs, snowpack water equivalent (SWE) and ion content, and stream water chemistry every 7-10 days along a 3150-3500 m elevation gradient in the subalpine and alpine Lexen Creek watershed. The study objectives were to (1) quantify the distribution of SWE and snowpack chemical content with elevation and aspect, (2) quantify snowmelt rates, temperature of soil, snowpack, and air with elevation and aspect, and (3) use change in upstream-downstream water chemistry during snowmelt to better define alpine and subalpine flowpaths. The SWE increased with elevation (P - 3??C) temperatures throughout winter which resulted in significant snowpack ion loss. By snowpack PWE in mid May, the snowpack had lost almost half the cumulative precipitation H+, NH4+, and SO42- inputs and a third of the NO3- input. Windborne soil particulate inputs late in winter increased snowpack base cation content. Variation in subalpine SWE and snowpack ion content with elevation and aspect, and wind redistribution of snowfall in the alpine resulted in large year-to-year differences in the timing and magnitude of SWE, PWE, and snowpack ion content. The alpine stream water ion concentrations changed little during snowmelt indicating meltwater passed quickly through surface porous soils and was well mixed before entering the stream. Conversely, subalpine stream water chemistry was diluted during snowmelt suggesting much melt water moved to the stream as shallow subsurface lateral flow. Published by Elsevier Science B.V.

High-Elevation Sierra Nevada Conifers Reveal Increasing Reliance on Snow Water with Changing Climate

NASA Astrophysics Data System (ADS)

Lepley, K. S.; Meko, D. M.; Touchan, R.; Shamir, E.; Graham, R.

2017-12-01

Snowpack in the Sierra Nevada Mountains accounts for around one third of California's water supply. Melting snow can provide water into dry summer months characteristic of the region's Mediterranean climate. As climate changes, understanding patterns of snowpack, snowmelt, and biological response are critical in this region of agricultural, recreational, and ecological value. Tree rings can act as proxy records to inform scientists and resource managers of past climate variability where instrumental data is unavailable. Here we investigate relationships between tree rings of high-elevation, snow-adapted conifer trees (Tsuga mertensiana, Abies magnifica) and April 1st snow-water equivalent (SWE) in the northern Sierra Nevada Mountains. The 1st principal component of 29 highly correlated regional SWE time series was modeled using multiple linear regression of four tree-ring chronologies including two lagged chronologies. Split-period verification analysis of this model revealed poor predictive skill in the early half (1929 - 1966) of the calibration period (1929 - 2003). Further analysis revealed a significant (p < 0.01) change in correlation between the Tsuga mertensiana chronology and SWE during early (1929 - 1970) and late (1971 - 2013) periods. Running 31-year correlations between this chronology and SWE rose from r = 0.10 in 1950 to r = 0.77 in 1996. This strengthening relationship is coincident with a positive trend in temperature, a negative trend in SWE, and increased variability in precipitation through time. Snow water is becoming a more limiting resource to tree growth as average temperatures rise and the hydrologic regime shifts. These results highlight the need for resource managers and policy makers to consider that biological response to climate is not static.

Measuring snow water equivalent from common-offset GPR records through migration velocity analysis

NASA Astrophysics Data System (ADS)

St. Clair, James; Holbrook, W. Steven

2017-12-01

Many mountainous regions depend on seasonal snowfall for their water resources. Current methods of predicting the availability of water resources rely on long-term relationships between stream discharge and snowpack monitoring at isolated locations, which are less reliable during abnormal snow years. Ground-penetrating radar (GPR) has been shown to be an effective tool for measuring snow water equivalent (SWE) because of the close relationship between snow density and radar velocity. However, the standard methods of measuring radar velocity can be time-consuming. Here we apply a migration focusing method originally developed for extracting velocity information from diffracted energy observed in zero-offset seismic sections to the problem of estimating radar velocities in seasonal snow from common-offset GPR data. Diffractions are isolated by plane-wave-destruction (PWD) filtering and the optimal migration velocity is chosen based on the varimax norm of the migrated image. We then use the radar velocity to estimate snow density, depth, and SWE. The GPR-derived SWE estimates are within 6 % of manual SWE measurements when the GPR antenna is coupled to the snow surface and 3-21 % of the manual measurements when the antenna is mounted on the front of a snowmobile ˜ 0.5 m above the snow surface.

Improving gridded snow water equivalent products in British Columbia, Canada: multi-source data fusion by neural network models

NASA Astrophysics Data System (ADS)

Snauffer, Andrew M.; Hsieh, William W.; Cannon, Alex J.; Schnorbus, Markus A.

2018-03-01

Estimates of surface snow water equivalent (SWE) in mixed alpine environments with seasonal melts are particularly difficult in areas of high vegetation density, topographic relief, and snow accumulations. These three confounding factors dominate much of the province of British Columbia (BC), Canada. An artificial neural network (ANN) was created using as predictors six gridded SWE products previously evaluated for BC. Relevant spatiotemporal covariates were also included as predictors, and observations from manual snow surveys at stations located throughout BC were used as target data. Mean absolute errors (MAEs) and interannual correlations for April surveys were found using cross-validation. The ANN using the three best-performing SWE products (ANN3) had the lowest mean station MAE across the province. ANN3 outperformed each product as well as product means and multiple linear regression (MLR) models in all of BC's five physiographic regions except for the BC Plains. Subsequent comparisons with predictions generated by the Variable Infiltration Capacity (VIC) hydrologic model found ANN3 to better estimate SWE over the VIC domain and within most regions. The superior performance of ANN3 over the individual products, product means, MLR, and VIC was found to be statistically significant across the province.

Can continuous scans in orthogonal planes improve diagnostic performance of shear wave elastography for breast lesions?

PubMed

Yang, Pan; Peng, Yulan; Zhao, Haina; Luo, Honghao; Jin, Ya; He, Yushuang

2015-01-01

Static shear wave elastography (SWE) is used to detect breast lesions, but slice and plane selections result in discrepancies. To evaluate the intraobserver reproducibility of continuous SWE, and whether quantitative elasticities in orthogonal planes perform better in the differential diagnosis of breast lesions. One hundred and twenty-two breast lesions scheduled for ultrasound-guided biopsy were recruited. Continuous SWE scans were conducted in orthogonal planes separately. Quantitative elasticities and histopathology results were collected. Reproducibility in the same plane and diagnostic performance in different planes were evaluated. The maximum and mean elasticities of the hardest portion, and standard deviation of whole lesion, had high inter-class correlation coefficients (0.87 to 0.95) and large areas under receiver operation characteristic curve (0.887 to 0.899). Without loss of accuracy, sensitivities had increased in orthogonal planes compared with single plane (from 73.17% up to 82.93% at most). Mean elasticity of whole lesion and lesion-to-parenchyma ratio were significantly less reproducible and less accurate. Continuous SWE is highly reproducible for the same observer. The maximum and mean elasticities of the hardest portion and standard deviation of whole lesion are most reliable. Furthermore, the sensitivities of the three parameters are improved in orthogonal planes without loss of accuracies.

Retrospective forecasts of the upcoming winter season snow accumulation in the Inn headwaters (European Alps)

NASA Astrophysics Data System (ADS)

Förster, Kristian; Hanzer, Florian; Stoll, Elena; Scaife, Adam A.; MacLachlan, Craig; Schöber, Johannes; Huttenlau, Matthias; Achleitner, Stefan; Strasser, Ulrich

2018-02-01

This article presents analyses of retrospective seasonal forecasts of snow accumulation. Re-forecasts with 4 months' lead time from two coupled atmosphere-ocean general circulation models (NCEP CFSv2 and MetOffice GloSea5) drive the Alpine Water balance and Runoff Estimation model (AWARE) in order to predict mid-winter snow accumulation in the Inn headwaters. As snowpack is hydrological storage that evolves during the winter season, it is strongly dependent on precipitation totals of the previous months. Climate model (CM) predictions of precipitation totals integrated from November to February (NDJF) compare reasonably well with observations. Even though predictions for precipitation may not be significantly more skilful than for temperature, the predictive skill achieved for precipitation is retained in subsequent water balance simulations when snow water equivalent (SWE) in February is considered. Given the AWARE simulations driven by observed meteorological fields as a benchmark for SWE analyses, the correlation achieved using GloSea5-AWARE SWE predictions is r = 0.57. The tendency of SWE anomalies (i.e. the sign of anomalies) is correctly predicted in 11 of 13 years. For CFSv2-AWARE, the corresponding values are r = 0.28 and 7 of 13 years. The results suggest that some seasonal prediction of hydrological model storage tendencies in parts of Europe is possible.

A novel web-enabled healthcare solution on health vault system.

PubMed

Liao, Lingxia; Chen, Min; Rodrigues, Joel J P C; Lai, Xiaorong; Vuong, Son

2012-06-01

Complicated Electronic Medical Records (EMR) systems have created problems in systems regarding an easy implementation and interoperability for a Web-enabled Healthcare Solution, which is normally provided by an independent healthcare giver with limited IT knowledge and interests. An EMR system with well-designed and user-friendly interface, such as Microsoft HealthVault System used as the back-end platform of a Web-enabled healthcare application will be an approach to deal with these problems. This paper analyzes the patient oriented Web-enabled healthcare service application as the new trend to delivery healthcare from hospital/clinic-centric to patient-centric, the current e-healthcare applications, and the main backend EMR systems. Then, we present a novel web-enabled healthcare solution based on Microsoft HealthVault EMR system to meet customers' needs, such as, low total cost, easily development and maintenance, and good interoperability. A sample system is given to show how the solution can be fulfilled, evaluated, and validated. We expect that this paper will provide a deep understanding of the available EMR systems, leading to insights for new solutions and approaches driven to next generation EMR systems.

Facilitating Collaboration, Knowledge Construction and Communication with Web-Enabled Databases.

ERIC Educational Resources Information Center

McNeil, Sara G.; Robin, Bernard R.

This paper presents an overview of World Wide Web-enabled databases that dynamically generate Web materials and focuses on the use of this technology to support collaboration, knowledge construction, and communication. Database applications have been used in classrooms to support learning activities for over a decade, but, although business and…

A Tutorial in Creating Web-Enabled Databases with Inmagic DB/TextWorks through ODBC.

ERIC Educational Resources Information Center

Breeding, Marshall

2000-01-01

Explains how to create Web-enabled databases. Highlights include Inmagic's DB/Text WebPublisher product called DB/TextWorks; ODBC (Open Database Connectivity) drivers; Perl programming language; HTML coding; Structured Query Language (SQL); Common Gateway Interface (CGI) programming; and examples of HTML pages and Perl scripts. (LRW)

Telecommunications Relay Service

MedlinePlus

... used with an existing voice telephone and a computer or other Web-enabled device without requiring any ... based TRS call. The user may use a computer or other web-enabled device to communicate with ...

Datacube Interoperability, Encoding Independence, and Analytics

NASA Astrophysics Data System (ADS)

Baumann, Peter; Hirschorn, Eric; Maso, Joan

2017-04-01

Datacubes are commonly accepted as an enabling paradigm which provides a handy abstraction for accessing and analyzing the zillions of image files delivered by the manifold satellite instruments and climate simulations, among others. Additionally, datacubes are the classic model for statistical and OLAP datacubes, so a further information category can be integrated. From a standards perspective, spatio-temporal datacubes naturally are included in the concept of coverages which encompass regular and irregular grids, point clouds, and general meshes - or, more abstractly, digital representations of spatio-temporally varying phenomena. ISO 19123, which is identical to OGC Abstract Topic 6, gives a high-level abstract definition which is complemented by the OGC Coverage Implementation Schema (CIS) which is an interoperable, yet format independent concretization of the abstract model. Currently, ISO is working on adopting OGC CIS as ISO 19123-2; the existing ISO 19123 standard is under revision by one of the abstract authors and will become ISO 19123-1. The roadmap agreed by ISO further foresees adoption of the OGC Web Coverage Service (WCS) as an ISO standard so that a complete data and service model will exist. In 2016, INSPIRE has adopted WCS as Coverage Download Service, including the datacube analytics language Web Coverage Processing Service (WCPS). The rasdaman technology (www.rasdaman.org) is both OGC and INSPIRE Reference Implementation. In the global EarthServer initiative rasdaman database sizes are exceeding 250 TB today, heading for the Petabyte frontier well in 2017. Technically, CIS defines a compact, efficient model for representing multi-dimensional datacubes in several ways. The classical coverage cube defines a domain set (where are values?), a range set (what are these values?), and range type (what do the values mean?), as well as a "bag" for arbitrary metadata. With CIS 1.1, coordinate/value pair sequences have been added, as well as tiled representations. Further, CIS 1.1 offers a unified model for any kind of regular and irregular grids, also allowing sensor models as per SensorML. Encodings include ASCII formats like GML, JSON, RDF as well as binary formats like GeoTIFF, NetCDF, JPEG2000, and GRIB2; further, a container concept allows mixed representations within one coverage file utilizing zip or other convenient package formats. Through the tight integration with the Sensor Web Enablement (SWE), a lossless "transport" from sensor into coverage world is ensured. The corresponding service model of WCS supports datacube operations ranging from simple data extraction to complex ad-hoc analytics with WPCS. Notably, W3C is working has set out on a coverage model as well; it has been designed relatively independently from the abovementioned standards, but there is informal agreement to link it into the CIS universe (which allows for different, yet interchangeable representations). Particularly interesting in the W3C proposal is the detailed semantic modeling of metadata; as CIS 1.1 supports RDF, a tight coupling seems feasible.

Assessment of Surface Water Storage trends for increasing groundwater areas in India

NASA Astrophysics Data System (ADS)

Banerjee, Chandan; Kumar, D. Nagesh

2018-07-01

Recent studies based on Gravity Recovery and Climate Experiment (GRACE) satellite mission suggested that groundwater has increased in central and southern parts of India. However, surface water, which is an equally important source of water in these semi-arid areas has not been studied yet. In the present study, the study areas were outlined based on trends in GRACE data followed by trend identification in surface water storages and checking the hypothesis of causality. Surface Water Extent (SWE) and Surface Soil Moisture (SSM) derived from Moderate-resolution Imaging Spectroradiometer (MODIS) and Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E) respectively, are selected as proxies of surface water storage (SWS). Besides SWE and SSM, trend test was performed for GRACE derived terrestrial water storage (TWS) for the study areas named as R1, R2, GOR1 and KOR1. Granger-causality test is used to test the hypothesis that rainfall is a causal factor of the inter-annual variability of SWE, SSM and TWS. Positive trends were observed in TWS for R1, R2 and GOR1 whereas SWE and SSM show increasing trends for all the study regions. Results suggest that rainfall is the granger-causal of all the storage variables for R1 and R2, the regions exhibiting the most significant positive trends in TWS.

Morphogenesis checkpoint kinase Swe1 is the executor of lipolysis-dependent cell-cycle progression

PubMed Central

Chauhan, Neha; Visram, Myriam; Cristobal-Sarramian, Alvaro; Sarkleti, Florian

2015-01-01

Cell growth and division requires the precise duplication of cellular DNA content but also of membranes and organelles. Knowledge about the cell-cycle–dependent regulation of membrane and storage lipid homeostasis is only rudimentary. Previous work from our laboratory has shown that the breakdown of triacylglycerols (TGs) is regulated in a cell-cycle–dependent manner, by activation of the Tgl4 lipase by the major cyclin-dependent kinase Cdc28. The lipases Tgl3 and Tgl4 are required for efficient cell-cycle progression during the G1/S (Gap1/replication phase) transition, at the onset of bud formation, and their absence leads to a cell-cycle delay. We now show that defective lipolysis activates the Swe1 morphogenesis checkpoint kinase that halts cell-cycle progression by phosphorylation of Cdc28 at tyrosine residue 19. Saturated long-chain fatty acids and phytosphingosine supplementation rescue the cell-cycle delay in the Tgl3/Tgl4 lipase-deficient strain, suggesting that Swe1 activity responds to imbalanced sphingolipid metabolism, in the absence of TG degradation. We propose a model by which TG-derived sphingolipids are required to activate the protein phosphatase 2A (PP2ACdc55) to attenuate Swe1 phosphorylation and its inhibitory effect on Cdc28 at the G1/S transition of the cell cycle. PMID:25713391

Morphogenesis checkpoint kinase Swe1 is the executor of lipolysis-dependent cell-cycle progression.

PubMed

Chauhan, Neha; Visram, Myriam; Cristobal-Sarramian, Alvaro; Sarkleti, Florian; Kohlwein, Sepp D

2015-03-10

Cell growth and division requires the precise duplication of cellular DNA content but also of membranes and organelles. Knowledge about the cell-cycle-dependent regulation of membrane and storage lipid homeostasis is only rudimentary. Previous work from our laboratory has shown that the breakdown of triacylglycerols (TGs) is regulated in a cell-cycle-dependent manner, by activation of the Tgl4 lipase by the major cyclin-dependent kinase Cdc28. The lipases Tgl3 and Tgl4 are required for efficient cell-cycle progression during the G1/S (Gap1/replication phase) transition, at the onset of bud formation, and their absence leads to a cell-cycle delay. We now show that defective lipolysis activates the Swe1 morphogenesis checkpoint kinase that halts cell-cycle progression by phosphorylation of Cdc28 at tyrosine residue 19. Saturated long-chain fatty acids and phytosphingosine supplementation rescue the cell-cycle delay in the Tgl3/Tgl4 lipase-deficient strain, suggesting that Swe1 activity responds to imbalanced sphingolipid metabolism, in the absence of TG degradation. We propose a model by which TG-derived sphingolipids are required to activate the protein phosphatase 2A (PP2A(Cdc55)) to attenuate Swe1 phosphorylation and its inhibitory effect on Cdc28 at the G1/S transition of the cell cycle.

ESA situational awareness of space weather

NASA Astrophysics Data System (ADS)

Luntama, Juha-Pekka; Glover, Alexi; Keil, Ralf; Kraft, Stefan; Lupi, Adriano

2016-07-01

ESA SSA Period 2 started at the beginning of 2013 and will last until the end of 2016. For the Space Weather Segment, transition to Period 2 introduced an increasing amount of development of new space weather service capability in addition to networking existing European assets. This transition was started already towards the end of SSA Period 1 with the initiation of the SSA Space Weather Segment architecture definition studies and activities enhancing existing space weather assets. The objective of Period 2 has been to initiate SWE space segment developments in the form of hosted payload missions and further expand the federated service network. A strong focus has been placed on demonstration and testing of European capabilities in the range of SWE service domains with a view to establishing core products which can form the basis of SWE service provision during SSA Period 3. This focus has been particularly addressed in the SSA Expert Service Centre (ESC) Definition and Development activity that was started in September 2015. This presentation will cover the current status of the SSA SWE Segment and the achievements during SSA Programme Periods 1 and 2. Particular attention is given to the federated approach that allow building the end user services on the best European expertise. The presentation will also outline the plans for the Space Weather capability development in the framework of the ESA SSA Programme in 2017-2020.

Estimating snow water equivalent from GPS vertical site-position observations in the western United States

PubMed Central

Ouellette, Karli J; de Linage, Caroline; Famiglietti, James S

2013-01-01

[1] Accurate estimation of the characteristics of the winter snowpack is crucial for prediction of available water supply, flooding, and climate feedbacks. Remote sensing of snow has been most successful for quantifying the spatial extent of the snowpack, although satellite estimation of snow water equivalent (SWE), fractional snow covered area, and snow depth is improving. Here we show that GPS observations of vertical land surface loading reveal seasonal responses of the land surface to the total weight of snow, providing information about the stored SWE. We demonstrate that the seasonal signal in Scripps Orbit and Permanent Array Center (SOPAC) GPS vertical land surface position time series at six locations in the western United States is driven by elastic loading of the crust by the snowpack. GPS observations of land surface deformation are then used to predict the water load as a function of time at each location of interest and compared for validation to nearby Snowpack Telemetry observations of SWE. Estimates of soil moisture are included in the analysis and result in considerable improvement in the prediction of SWE. Citation: Ouellette, K. J., C. de Linage, and J. S. Famiglietti (2013), Estimating snow water equivalent from GPS vertical site-position observations in the western United States, Water Resour. Res., 49, 2508–2518, doi:10.1002/wrcr.20173. PMID:24223442

A Distributive, Non-Destructive, Real-Time Approach to Snowpack Monitoring

NASA Technical Reports Server (NTRS)

Frolik, Jeff; Skalka, Christian

2012-01-01

This invention is designed to ascertain the snow water equivalence (SWE) of snowpacks with better spatial and temporal resolutions than present techniques. The approach is ground-based, as opposed to some techniques that are air-based. In addition, the approach is compact, non-destructive, and can be communicated with remotely, and thus can be deployed in areas not possible with current methods. Presently there are two principal ground-based techniques for obtaining SWE measurements. The first is manual snow core measurements of the snowpack. This approach is labor-intensive, destructive, and has poor temporal resolution. The second approach is to deploy a large (e.g., 3x3 m) snowpillow, which requires significant infrastructure, is potentially hazardous [uses a approximately equal to 200-gallon (approximately equal to 760-L) antifreeze-filled bladder], and requires deployment in a large, flat area. High deployment costs necessitate few installations, thus yielding poor spatial resolution of data. Both approaches have limited usefulness in complex and/or avalanche-prone terrains. This approach is compact, non-destructive to the snowpack, provides high temporal resolution data, and due to potential low cost, can be deployed with high spatial resolution. The invention consists of three primary components: a robust wireless network and computing platform designed for harsh climates, new SWE sensing strategies, and algorithms for smart sampling, data logging, and SWE computation.

Shear wave elastography diagnosis of the diffuse sclerosing variant of papillary thyroid carcinoma: A case report.

PubMed

Xue, Nianyu; Xu, Youfeng; Huang, Pintong; Zhang, Shengmin; Wang, Hongwei; Yu, Fei

2016-08-01

The present study aimed to report the shear wave elastography (SWE) findings in a patient with the diffuse sclerosing variant of papillary thyroid carcinoma (DSVPTC). Since patients with DSVPTC may present with typical clinicopathological features and initially appear to have Hashimoto's thyroiditis, a thorough clinical evaluation and an early diagnosis are important. A 20-year-old female patient presented with a 1-month history of a neck mass and sore throat. Conventional ultrasound and SWE were performed using an AIXPLORER system with 14-5 MHz linear transducer. The patient had undergone total thyroidectomy and bilateral neck lymph node dissection, and an intraoperative pathology consultation to confirm the malignancy of lymph node metastasis. Pathological diagnosis was DSVPTC in both lobes, with lymph node metastases in the bilateral neck. The clinical presentation and serological findings were all indicative of Hashimoto's thyroiditis. Thyroid ultrasonography revealed diffuse enlargement of the both lobes, heterogenous echogenicity without mass formation, diffuse scattered microcalcifications and poor vascularization. SWE revealed stiff values of the thyroid: The mean stiffness was 99.7 kpa, the minimum stiffness was 59.1 kpa and the maximum stiffness was 180.1 kpa. The maximum stiffness of the DSVPTC (180.1 kpa) was higher compared with the diagnostic criteria of malignant thyroid nodules (65 kPa). SWE may be considered as a novel and valuable method to diagnose DSVPC.

Shear wave elastography diagnosis of the diffuse sclerosing variant of papillary thyroid carcinoma: A case report

PubMed Central

Xue, Nianyu; Xu, Youfeng; Huang, Pintong; Zhang, Shengmin; Wang, Hongwei; Yu, Fei

2016-01-01

The present study aimed to report the shear wave elastography (SWE) findings in a patient with the diffuse sclerosing variant of papillary thyroid carcinoma (DSVPTC). Since patients with DSVPTC may present with typical clinicopathological features and initially appear to have Hashimoto's thyroiditis, a thorough clinical evaluation and an early diagnosis are important. A 20-year-old female patient presented with a 1-month history of a neck mass and sore throat. Conventional ultrasound and SWE were performed using an AIXPLORER system with 14-5 MHz linear transducer. The patient had undergone total thyroidectomy and bilateral neck lymph node dissection, and an intraoperative pathology consultation to confirm the malignancy of lymph node metastasis. Pathological diagnosis was DSVPTC in both lobes, with lymph node metastases in the bilateral neck. The clinical presentation and serological findings were all indicative of Hashimoto's thyroiditis. Thyroid ultrasonography revealed diffuse enlargement of the both lobes, heterogenous echogenicity without mass formation, diffuse scattered microcalcifications and poor vascularization. SWE revealed stiff values of the thyroid: The mean stiffness was 99.7 kpa, the minimum stiffness was 59.1 kpa and the maximum stiffness was 180.1 kpa. The maximum stiffness of the DSVPTC (180.1 kpa) was higher compared with the diagnostic criteria of malignant thyroid nodules (65 kPa). SWE may be considered as a novel and valuable method to diagnose DSVPC. PMID:27446574

Visually assessed colour overlay features in shear-wave elastography for breast masses: quantification and diagnostic performance.

PubMed

Gweon, Hye Mi; Youk, Ji Hyun; Son, Eun Ju; Kim, Jeong-Ah

2013-03-01

To determine whether colour overlay features can be quantified by the standard deviation (SD) of the elasticity measured in shear-wave elastography (SWE) and to evaluate the diagnostic performance for breast masses. One hundred thirty-three breast lesions in 119 consecutive women who underwent SWE before US-guided core needle biopsy or surgical excision were analysed. SWE colour overlay features were assessed using two different colour overlay pattern classifications. Quantitative SD of the elasticity value was measured with the region of interest including the whole breast lesion. For the four-colour overlay pattern, the area under the ROC curve (Az) was 0.947; with a cutoff point between pattern 2 and 3, sensitivity and specificity were 94.4 % and 81.4 %. According to the homogeneity of the elasticity, the Az was 0.887; with a cutoff point between reasonably homogeneous and heterogeneous, sensitivity and specificity were 86.1 % and 82.5 %. For the SD of the elasticity, the Az was 0.944; with a cutoff point of 12.1, sensitivity and specificity were 88.9 % and 89.7 %. The colour overlay features showed significant correlations with the quantitative SD of the elasticity (P < 0.001). The colour overlay features and the SD of the elasticity in SWE showed excellent diagnostic performance and showed good correlations between them.

Repeatability of shear wave elastography in liver fibrosis phantoms—Evaluation of five different systems

PubMed Central

2018-01-01

This study aimed to assess and validate the repeatability and agreement of quantitative elastography of novel shear wave methods on four individual tissue-mimicking liver fibrosis phantoms with different known Young’s modulus. We used GE Logiq E9 2D-SWE, Philips iU22 ARFI (pSWE), Samsung TS80A SWE (pSWE), Hitachi Ascendus (SWM) and Transient Elastography (TE). Two individual investigators performed all measurements non-continued and in parallel. The methods were evaluated for inter- and intraobserver variability by intraclass correlation, coefficient of variation and limits of agreement using the median elastography value. All systems used in this study provided high repeatability in quantitative measurements in a liver fibrosis phantom and excellent inter- and intraclass correlations. All four elastography platforms showed excellent intra-and interobserver agreement (interclass correlation 0.981–1.000 and intraclass correlation 0.987–1.000) and no significant difference in mean elasticity measurements for all systems, except for TE on phantom 4. All four liver fibrosis phantoms could be differentiated by quantitative elastography, by all platforms (p<0.001). In the Bland-Altman analysis the differences in measurements were larger for the phantoms with higher Young’s modulus. All platforms had a coefficient of variation in the range 0.00–0.21 for all four phantoms, equivalent to low variance and high repeatability. PMID:29293527

Proteus - A Free and Open Source Sensor Observation Service (SOS) Client

NASA Astrophysics Data System (ADS)

Henriksson, J.; Satapathy, G.; Bermudez, L. E.

2013-12-01

The Earth's 'electronic skin' is becoming ever more sophisticated with a growing number of sensors measuring everything from seawater salinity levels to atmospheric pressure. To further the scientific application of this data collection effort, it is important to make the data easily available to anyone who wants to use it. Making Earth Science data readily available will allow the data to be used in new and potentially groundbreaking ways. The US National Science and Technology Council made this clear in its most recent National Strategy for Civil Earth Observations report, when it remarked that Earth observations 'are often found to be useful for additional purposes not foreseen during the development of the observation system'. On the road to this goal the Open Geospatial Consortium (OGC) is defining uniform data formats and service interfaces to facilitate the discovery and access of sensor data. This is being done through the Sensor Web Enablement (SWE) stack of standards, which include the Sensor Observation Service (SOS), Sensor Model Language (SensorML), Observations & Measurements (O&M) and Catalog Service for the Web (CSW). End-users do not have to use these standards directly, but can use smart tools that leverage and implement them. We have developed such a tool named Proteus. Proteus is an open-source sensor data discovery client. The goal of Proteus is to be a general-purpose client that can be used by anyone for discovering and accessing sensor data via OGC-based services. Proteus is a desktop client and supports a straightforward workflow for finding sensor data. The workflow takes the user through the process of selecting appropriate services, bounding boxes, observed properties, time periods and other search facets. NASA World Wind is used to display the matching sensor offerings on a map. Data from any sensor offering can be previewed in a time series. The user can download data from a single sensor offering, or download data in bulk from all matching sensor offerings. Proteus leverages NASA World Wind's WMS capabilities and allow overlaying sensor offerings on top of any map. Specific search criteria (i.e. user discoveries) can be saved and later restored. Proteus is supports two user types: 1) the researcher/scientist interested in discovering and downloading specific sensor data as input to research processes, and 2) the data manager responsible for maintaining sensor data services (e.g. SOSs) and wants to ensure proper data and metadata delivery, verify sensor data, and receive sensor data alerts. Proteus has a Web-based companion product named the Community Hub that is used to generate sensor data alerts. Alerts can be received via an RSS feed, viewed in a Web browser or displayed directly in Proteus via a Web-based API. To advance the vision of making Earth Science data easily discoverable and accessible to end-users, professional or laymen, Proteus is available as open-source on GitHub (https://github.com/intelligentautomation/proteus).

Finding, Browsing and Getting Data Easily Using SPDF Web Services

NASA Technical Reports Server (NTRS)

Candey, R.; Chimiak, R.; Harris, B.; Johnson, R.; Kovalick, T.; Lal, N.; Leckner, H.; Liu, M.; McGuire, R.; Papitashvili, N.;

A Tsunami-Focused Tide Station Data Sharing Framework

NASA Astrophysics Data System (ADS)

Kari, U. S.; Marra, J. J.; Weinstein, S. A.

2006-12-01

The Indian Ocean Tsunami of 26 December 2004 made it clear that information about tide stations that could be used to support detection and warning (such as location, collection and transmission capabilities, operator identification) are insufficiently known or not readily accessible. Parties interested in addressing this problem united under the Pacific Region Data Integrated Data Enterprise (PRIDE), and in 2005 began a multiyear effort to develop a distributed metadata system describing tide stations starting with pilot activities in a regional framework and focusing on tsunami detection and warning systems being developed by various agencies. First, a plain semantic description of the tsunami-focused tide station metadata was developed. The semantic metadata description was, in turn, developed into a formal metadata schema championed by International Tsunami Information Centre (ITIC) as part of a larger effort to develop a prototype web service under the PRIDE program in 2005. Under the 2006 PRIDE program the formal metadata schema was then expanded to corral input parameters for the TideTool application used by Pacific Tsunami Warning Center (PTWC) to drill down into wave activity at a tide station that is located using a web service developed on this metadata schema. This effort contributed to formalization of web service dissemination of PTWC watch and warning tsunami bulletins. During this time, the data content and sharing issues embodied in this schema have been discussed at various forums. The result is that the various stakeholders have different data provider and user perspectives (semantic content) and also exchange formats (not limited to just XML). The challenge then, is not only to capture all data requirements, but also to have formal representation that is easily transformed into any specified format. The latest revision of the tide gauge schema (Version 0.3), begins to address this challenge. It encompasses a broader range of provider and user perspectives, such as station operators, warning system managers, disaster managers, other marine hazard warning systems (such as storm surges and sea level change monitoring and research. In the next revision(s), we hope to take into account various relevant standards, including specifically, the Open Geospatial Consortium (OGC) Sensor Web Enablement (SWE) Framework, that will serve all prospective stakeholders in the most useful (extensible, scalable) manner. This is because Sensor ML has addressed many of the challenges we face already, through very useful fundamental modeling consideration and data types that are particular to sensors in general, with perhaps some extension needed for tide gauges. As a result of developing this schema, and associated client application architectures, we hope to have a much more distributed network of data providers, who are able to contribute to a global tide station metadata from the comfort of their own Information Technology (IT) departments.

Assessing the utility of passive microwave data for Snow Water Equivalent (SWE) estimation in the Sutlej River Basin of the northwestern Himalaya

NASA Astrophysics Data System (ADS)

Brandt, T.; Bookhagen, B.; Dozier, J.

2014-12-01

Since 1978, space based passive microwave (PM) radiometers have been used to comprehensively measure Snow Water Equivalent (SWE) on a global basis. The ability of PM radiometers to directly measure SWE at high temporal frequencies offers some distinct advantages over optical remote sensors. Nevertheless, in mountainous terrain PM radiometers often struggle to accurately measure SWE because of wet snow, saturation in deep snow, forests, depth hoar and stratigraphy, variable relief, and subpixel heterogeneity inherent in large pixel sizes. The Himalaya, because of their high elevation and high relief—much above tree line—offer an opportunity to examine PM products in the mountains without the added complication of trees. The upper Sutlej River basin— the third largest Himalayan catchment—lies in the western Himalaya. The river is a tributary of the Indus River and seasonal snow constitutes a substantial part of the basin's hydrologic budget. The basin has a few surface stations and river gauges, which is unique for the region. As such, the Sutlej River basin is a good location to analyze the accuracy and effectiveness of the current National Snow and Ice Data Center's (NSIDC) standard AMSR-E/Aqua Daily SWE product in mountainous terrain. So far, we have observed that individual pixels can "flicker", i.e. fluctuate from day to day, over large parts of the basin. We consider whether this is an artifact of the algorithm or whether this is embedded in the raw brightness temperatures themselves. In addition, we examine how well the standard product registers winter storms, and how it varies over heavily glaciated pixels. Finally, we use a few common measures of algorithm performance (precision, recall and accuracy) to test how well the standard product detects the presence of snow, using optical imagery for validation. An improved understanding of the effectiveness of PM imagery in the mountains will help to clarify the technology's limits.

Changes in the timing of snowmelt and streamflow in Colorado: A response to recent warming

USGS Publications Warehouse

Clow, David W.

2010-01-01

Trends in the timing of snowmelt and associated runoff in Colorado were evaluated for the 1978-2007 water years using the regional Kendall test (RKT) on daily snow-water equivalent (SWE) data from snowpack telemetry (SNOTEL) sites and daily streamflow data from headwater streams. The RKT is a robust, nonparametric test that provides an increased power of trend detection by grouping data from multiple sites within a given geographic region. The RKT analyses indicated strong, pervasive trends in snowmelt and streamflow timing, which have shifted toward earlier in the year by a median of 2-3 weeks over the 29-yr study period. In contrast, relatively few statistically significant trends were detected using simple linear regression. RKT analyses also indicated that November-May air temperatures increased by a median of 0.9 degrees C decade-1, while 1 April SWE and maximum SWE declined by a median of 4.1 and 3.6 cm decade-1, respectively. Multiple linear regression models were created, using monthly air temperatures, snowfall, latitude, and elevation as explanatory variables to identify major controlling factors on snowmelt timing. The models accounted for 45% of the variance in snowmelt onset, and 78% of the variance in the snowmelt center of mass (when half the snowpack had melted). Variations in springtime air temperature and SWE explained most of the interannual variability in snowmelt timing. Regression coefficients for air temperature were negative, indicating that warm temperatures promote early melt. Regression coefficients for SWE, latitude, and elevation were positive, indicating that abundant snowfall tends to delay snowmelt, and snowmelt tends to occur later at northern latitudes and high elevations. Results from this study indicate that even the mountains of Colorado, with their high elevations and cold snowpacks, are experiencing substantial shifts in the timing of snowmelt and snowmelt runoff toward earlier in the year.

Quantifying the accuracy of snow water equivalent estimates using broadband radar signal phase

NASA Astrophysics Data System (ADS)

Deeb, E. J.; Marshall, H. P.; Lamie, N. J.; Arcone, S. A.

2014-12-01

Radar wave velocity in dry snow depends solely on density. Consequently, ground-based pulsed systems can be used to accurately measure snow depth and snow water equivalent (SWE) using signal travel-time, along with manual depth-probing for signal velocity calibration. Travel-time measurements require a large bandwidth pulse not possible in airborne/space-borne platforms. In addition, radar backscatter from snow cover is sensitive to grain size and to a lesser extent roughness of layers at current/proposed satellite-based frequencies (~ 8 - 18 GHz), complicating inversion for SWE. Therefore, accurate retrievals of SWE still require local calibration due to this sensitivity to microstructure and layering. Conversely, satellite radar interferometry, which senses the difference in signal phase between acquisitions, has shown a potential relationship with SWE at lower frequencies (~ 1 - 5 GHz) because the phase of the snow-refracted signal is sensitive to depth and dielectric properties of the snowpack, as opposed to its microstructure and stratigraphy. We have constructed a lab-based, experimental test bed to quantify the change in radar phase over a wide range of frequencies for varying depths of dry quartz sand, a material dielectrically similar to dry snow. We use a laboratory grade Vector Network Analyzer (0.01 - 25.6 GHz) and a pair of antennae mounted on a trolley over the test bed to measure amplitude and phase repeatedly/accurately at many frequencies. Using ground-based LiDAR instrumentation, we collect a coordinated high-resolution digital surface model (DSM) of the test bed and subsequent depth surfaces with which to compare the radar record of changes in phase. Our plans to transition this methodology to a field deployment during winter 2014-2015 using precision pan/tilt instrumentation will also be presented, as well as applications to airborne and space-borne platforms toward the estimation of SWE at high spatial resolution (on the order of meters) over large regions (> 100 square kilometers).

Data Fusion of Gridded Snow Products Enhanced with Terrain Covariates and a Simple Snow Model

NASA Astrophysics Data System (ADS)

Snauffer, A. M.; Hsieh, W. W.; Cannon, A. J.

2017-12-01

Hydrologic planning requires accurate estimates of regional snow water equivalent (SWE), particularly areas with hydrologic regimes dominated by spring melt. While numerous gridded data products provide such estimates, accurate representations are particularly challenging under conditions of mountainous terrain, heavy forest cover and large snow accumulations, contexts which in many ways define the province of British Columbia (BC), Canada. One promising avenue of improving SWE estimates is a data fusion approach which combines field observations with gridded SWE products and relevant covariates. A base artificial neural network (ANN) was constructed using three of the best performing gridded SWE products over BC (ERA-Interim/Land, MERRA and GLDAS-2) and simple location and time covariates. This base ANN was then enhanced to include terrain covariates (slope, aspect and Terrain Roughness Index, TRI) as well as a simple 1-layer energy balance snow model driven by gridded bias-corrected ANUSPLIN temperature and precipitation values. The ANN enhanced with all aforementioned covariates performed better than the base ANN, but most of the skill improvement was attributable to the snow model with very little contribution from the terrain covariates. The enhanced ANN improved station mean absolute error (MAE) by an average of 53% relative to the composing gridded products over the province. Interannual peak SWE correlation coefficient was found to be 0.78, an improvement of 0.05 to 0.18 over the composing products. This nonlinear approach outperformed a comparable multiple linear regression (MLR) model by 22% in MAE and 0.04 in interannual correlation. The enhanced ANN has also been shown to estimate better than the Variable Infiltration Capacity (VIC) hydrologic model calibrated and run for four BC watersheds, improving MAE by 22% and correlation by 0.05. The performance improvements of the enhanced ANN are statistically significant at the 5% level across the province and in four out of five physiographic regions.

Snow drought in western U.S. mountains: proximate causes, regional differences, and implications for streamflow and forests

NASA Astrophysics Data System (ADS)

Harpold, A. A.; Dettinger, M. D.; Rajagopal, S.

2017-12-01

Although drought is a recurring problem, recent extreme snow droughts have refocused attention on the interaction of meteorological extremes and snow accumulation in mountains. Only recently have two distinct types of snow drought been defined that help to differentiate a variety of water management implications. Dry snow drought is caused by deficits of winter precipitation and resulting low snow accumulation. Warm snow drought is characterized by temperature extremes causing faster and earlier snowmelt and/or shifts from snow to rain. Here we use 462 Snow Telemetry (SNOTEL) sites in the western U.S. to quantify snow drought as 75% of the long-term average snow water equivalent (SWE). We further subdivide dry snow droughts using SWE to winter precipitation (SWE/P) ratios that were near normal from warm snow droughts where SWE/P ratios were below normal and experienced SWE losses (warm-melt) or received unusual amounts of winter rain (warm-rain snow drought). Using this method we show clear regional patterns in the type and frequency of snow drought. Warm snow droughts on April 1st were most common in all but the highest elevations of the Rocky Mountains. The middle Rocky Mountains sites also experienced less frequent snow drought than the maritime and southern mountains. Warm-melt snow droughts were the primary cause in the Cascade Mountains and the southwestern sites, with only the Sierra Nevada and Wasatch mountains showing consistent warm-rain snow drought. These regional differences limited the predictability of snow drought with simple models of temperature and precipitation. We will discuss the effects of snow drought type and magnitude on streamflow forecasting skill using empirical relationships developed by water management agencies. We expect these types of snow drought to differentially affect streamflow regime and its predictability, as well as forest growth and mortality during and following drought.

Using Gridded Snow Covered Area and Snow-Water Equivalence Spatial Data Sets to Improve Snow-Pack Depletion Simulation in a Continental Scale Hydrologic Model

NASA Astrophysics Data System (ADS)

Risley, J. C.; Tracey, J. A.; Markstrom, S. L.; Hay, L.

2014-12-01

Snow cover areal depletion curves were used in a continuous daily hydrologic model to simulate seasonal spring snowmelt during the period between maximum snowpack accumulation and total melt. The curves are defined as the ratio of snow-water equivalence (SWE) divided by the seasonal maximum snow-water equivalence (Ai) (Y axis) versus the percent snow cover area (SCA) (X axis). The slope of the curve can vary depending on local watershed conditions. Windy sparsely vegetated high elevation watersheds, for example, can have a steeper slope than lower elevation forested watersheds. To improve the accuracy of simulated runoff at ungaged watersheds, individual snow cover areal depletion curves were created for over 100,000 hydrologic response units (HRU) in the continental scale U.S. Geological Survey (USGS) National Hydrologic Model (NHM). NHM includes the same components of the USGS Precipitation-Runoff-Modeling System (PRMS), except it uses consistent land surface characterization and model parameterization across the U.S. continent. Weighted-mean daily time series of 1-kilometer gridded SWE, from Snow Data Assimilation System (SNODAS), and 500-meter gridded SCA, from Moderate Resolution Imaging Spectroradiometer (MODIS), for 2003-2014 were computed for each HRU using the USGS Geo Data Portal. Using a screening process, pairs of SWE/Ai and SCA from the snowmelt period of each year were selected. SCA values derived from imagery that did not have any cloud cover and were >0 and <100 percent were selected. Unrealistically low and high SCA values that were paired with high and low SWE/Ai ratios, respectively, were removed. Second order polynomial equations were then fit to the remaining pairs of SWE/Ai and SCA to create a unique curve for each HRU. Simulations comparing these new curves with an existing single default curve in NHM will be made to determine if there are significant improvements in runoff.

Real-Time Shear Wave versus Transient Elastography for Predicting Fibrosis: Applicability, and Impact of Inflammation and Steatosis. A Non-Invasive Comparison.

PubMed

Poynard, Thierry; Pham, Tam; Perazzo, Hugo; Munteanu, Mona; Luckina, Elena; Elaribi, Djamel; Ngo, Yen; Bonyhay, Luminita; Seurat, Noemie; Legroux, Muriel; Ngo, An; Deckmyn, Olivier; Thabut, Dominique; Ratziu, Vlad; Lucidarme, Olivier

2016-01-01

Real-time shear wave elastography (2D-SWE) is a two-dimensional transient elastography and a competitor as a biomarker of liver fibrosis in comparison with the standard reference transient elastography by M probe (TE-M). The aims were to compare several criteria of applicability, and to assess inflammation and steatosis impact on elasticity values, two unmet needs. We took FibroTest as the fibrosis reference and ActiTest and SteatoTest as quantitative estimates of inflammation and steatosis. After standardization of estimates, analyses used curve fitting, quantitative Lin concordance coefficient [LCC], and multivariate logistic regression. A total of 2,251 consecutive patients were included. We validated the predetermined 0.2 kPa cut-off as a too low minimal elasticity value identifying not-reliable 2D-SWE results (LCC with FibroTest = 0.0281[-0.119;0.175]. Other criteria, elasticity CV, body mass index and depth of measures were not sufficiently discriminant. The applicability of 2D-SWE (95%CI) 89.6%(88.2-90.8), was significantly higher than that of TE, 85.6%(84.0-87.0; P<0.0001). In patients with non-advanced fibrosis (METAVIR F0F1F2), elasticity values estimated by 2D-SWE was less impacted by inflammation and steatosis than elasticity value estimated by TE-M: LCC (95%CI) 0.039 (0.021;0.058) vs 0.090 (0.068;0.112;P<0.01) and 0.105 (0.068;0.141) vs 0.192 (0.153;0.230; P<0.01) respectively. The three analyses methods gave similar results. Elasticity results including very low minimal signal in the region of interest should be considered not reliable. 2D-SWE had a higher applicability than TE, the reference elastography, with less impact of inflammation and steatosis especially in patients with non-advanced fibrosis, as presumed by blood tests. ClinicalTrials.gov NCT01927133.

Changes in the elasticity of fibroadenoma during the menstrual cycle determined by real-time sonoelastography.

PubMed

Kılıç, Fahrettin; Kayadibi, Yasemin; Kocael, Pinar; Velidedeoglu, Mehmet; Bas, Ahmet; Bakan, Selim; Aydogan, Fatih; Karatas, Adem; Yılmaz, Mehmet Halit

2015-06-01

Shear-wave elastography (SWE) presents quantitative data that thought to represent intrinsic features of the target tissue. Factors affecting the metabolism of the breast parenchyma as well as age, menstrual cycle, hormone levels, pregnancy and lactation, pre-compression artifact during the examination could affect these elastic intrinsic features. Aim of our study is to determine variation of fibroadenoma elasticity during the menstrual cycle (MC) by means of real-time shear-wave elastography (SWE) and identify the optimal time for SWE evaluation. Thirty volunteers (aged 20-40 years) who had biopsy-proven fibroadenoma greater than 1cm in diameter, with regular menstrual cycle and without contraceptive medication underwent SWE (ShearWave on Aixplorer, France) once weekly during MC. Statistical data were processed by using the software Statistical Package for the Social Sciences (SPSS) 19.0. A repeated measures analysis of variance was used for each lesion where the repeated factor was the elastographic measurements (premenstrual, menstrual and postmenstrual). Pillai's trace test was used. Pairwise correlation was calculated using Bonferroni correction. Values of p<0.05 were considered statistically significant. The mean elasticity value of fibroadenomas in mid-cycle was 28.49 ± 12.92 kPa, with the highest value obtained in the third week corresponding to the premenstrual stage (32.98 ± 13.35 kPa) and the lowest value obtained in the first week corresponding to the postmenstrual stage (25.39 ± 10.21 kPa). Differences between the elasticity values of fibroadenomas in premenstrual and postmenstrual periods were statistically significant (p<0.001). There were no significant differences in lesion size between the different phases of the menstrual cycle (p>0.05). In this study, we found that there is significant difference between the elasticity values of fibroadenomas on premenstrual and postmenstrual period. We propose that one week after menstruation would be appropriate time to perform breast SWE. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Evaluation of 2D- Shear Wave Elastography for Characterisation of Focal Liver Lesions.

PubMed

Gerber, Ludmila; Fitting, Daniel; Srikantharajah, Kajana; Weiler, Nina; Kyriakidou, Georgia; Bojunga, Joerg; Schulze, Falko; Bon, Dimitra; Zeuzem, Stefan; Friedrich-Rust, Mireen

2017-09-01

This is a prospective study for evaluation of 2D-shear wave elastography (2D-SWE) for characterisation and differentiation of benign und malignant focal liver lesions (FLLs). The patients referred to our ultrasound unit were prospectively included. B-mode ultrasound and 2D-SWE (Aixplorer® France) were performed for one FLL in each patient. Liver histology and/or contrast-enhanced imaging were used as a reference method. 140 patients with FLL were included. SWE acquisitions failed in 24% of them. Therefore, 106 patients with FLL could be analysed, 42/106 with benign and 64/106 with malignant FLLs. The median stiffness for benign FLLs was 16.4 (2.1-71.9) kPa: 16.55 kPa for 18 focal nodular hyperplasia (FNH), 16.35 kPa for 18 hemangioma, 9.8 kPa for 3 focal fatty sparings (FFS), 8.9 kPa for 1 adenoma, 20 kPa for one regenerative node and 29 kPa for one cholangiofibroma, and for the malignant FLLs 36 (4.1-142.9) kPa: 44.8 kPa for 16 hepatocellular carcinoma (HCC), 70.7 kPa for 7 cholangiocarcinoma (CCC) and 29.5 kPa for the 41 metastasis (p<0.001). Malignant FLLs were significantly stiffer than benign FLLs (p<0.0001). Cholangiocarcinomas were the stiffest malignant FFLs with significantly higher values as compared to HCCs and metastases (p=0.033 and p=0.0079, respectively). No significant difference in stiffness could be observed between the different benign FLL entities. No significant difference was observed whether 2D-SWE included the whole FLL, the periphery or only the hardest area of the FLL. 2D-SWE provides further characterising information for interpretation of FLLs and may be useful at least in differentiation of CCCs and HCCs.

Liver and spleen stiffness and their ratio assessed by real-time two dimensional-shear wave elastography in patients with liver fibrosis and cirrhosis due to chronic viral hepatitis.

PubMed

Grgurevic, Ivica; Puljiz, Zeljko; Brnic, Darko; Bokun, Tomislav; Heinzl, Renata; Lukic, Anita; Luksic, Boris; Kujundzic, Milan; Brkljacic, Boris

2015-11-01

To investigate the performance of real-time 2D shear wave elastography (RT 2D-SWE) for non-invasive staging of liver disease in patients with chronic viral hepatitis (CVH). Naive CVH patients underwent liver (LS) and spleen stiffness (SS) measurements by an intercostal approach. Patients with ALT >3× upper limit of normal, cholestasis as revealed by dilated intrahepatic biliary tree, and liver congestion were excluded. Results were expressed in kPa and compared to histological stage (Ishak) of liver fibrosis (LF). Patients with decompensated liver cirrhosis (LC) were diagnosed using standard clinical, ultrasound, and endoscopic criteria. Of 123 patients, LS was successfully measured in 79.7% and SS in 53.7%. LS accurately differentiated between liver disease stages, with cut-off values of 8.1 (AUC 0.991) for F ≥ 3, 10.8 kPa (AUC 0.954) for F ≥ 5, and 27 kPa (AUC 0.961) for decompensated LC. SS was significantly different between non-cirrhotic stages (F0-4) and LC (cut-off 24 kPa; AUC 0.821). While both LS and SS increased with liver disease progression, the difference between them decreased, as reflected by the stiffness ratio index. RT 2D-SWE can accurately differentiate between the stages of LF, and can distinguish LF from LC and compensated from decompensated LC. • RT 2D-SWE is an accurate method for assessment of liver fibrosis. • RT 2D-SWE is applicable in 80% of patients with chronic viral hepatitis. • RT 2D-SWE accurately differentiates compensated from decompensated liver cirrhosis. • Both liver and spleen stiffness increase with progression of liver fibrosis. • In cirrhosis, the difference between liver and spleen stiffness decreases.

Quantitative Assessment of Skin Stiffness in Localized Scleroderma Using Ultrasound Shear-Wave Elastography.

PubMed

Wang, Liyun; Yan, Feng; Yang, Yujia; Xiang, Xi; Qiu, Li

2017-07-01

The purpose of this study was to evaluate the usefulness of ultrasound shear-wave elastography (US-SWE) in characterization of localized scleroderma (LS), as well as in the disease staging. A total of 21 patients with 37 LS lesions were enrolled in this study. The pathologic stage (edema, sclerosis or atrophy) of the lesions was characterized by pathologic examination. The skin elastic modulus (E-values including E mean , E min , E max and E sd ) and thickness (h) was evaluated both in LS lesions and site-matched unaffected skin (normal controls) using US-SWE. The relative difference of E-values (E RD ) was calculated between each pair of lesions and its normal control for comparison among different pathologic stages. Of the 37 LS lesions, 2 were in edema, 22 were in sclerosis and 13 were in atrophy. US-SWE results showed a significant increase of skin elastic modulus and thickness in all lesions (p < 0.001 in sclerosis and p < 0.05 in atrophy) compared with the normal controls. The measured skin elastic modulus and thickness were greater in sclerosis than in atrophy. However, once normalized by skin thickness, the atrophic lesions, which were on average thinner, appeared significantly stiffer than those of the sclerosis (normalized E RD : an increase of 316.3% in atrophy vs. 50.6% in sclerosis compared with the controls, p = 0.007). These findings suggest that US-SWE allows for quantitative evaluation of the skin stiffness of LS lesions in different stages; however, the E-values directly provided by the US-SWE system alone do not distinguish between the stages, and the normalization by skin thickness is necessary. This non-invasive, real-time imaging technique is an ideal tool for assessing and monitoring LS disease severity and progression. Copyright © 2017 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

The AMSR2 Satellite-based Microwave Snow Algorithm (SMSA) to estimate regional to global snow depth and snow water equivalent

NASA Astrophysics Data System (ADS)

Kelly, R. E. J.; Saberi, N.; Li, Q.

2017-12-01

With moderate to high spatial resolution (<1 km) regional to global snow water equivalent (SWE) observation approaches yet to be fully scoped and developed, the long-term satellite passive microwave record remains an important tool for cryosphere-climate diagnostics. A new satellite microwave remote sensing approach is described for estimating snow depth (SD) and snow water equivalent (SWE). The algorithm, called the Satellite-based Microwave Snow Algorithm (SMSA), uses Advanced Microwave Scanning Radiometer - 2 (AMSR2) observations aboard the Global Change Observation Mission - Water mission launched by the Japan Aerospace Exploration Agency in 2012. The approach is unique since it leverages observed brightness temperatures (Tb) with static ancillary data to parameterize a physically-based retrieval without requiring parameter constraints from in situ snow depth observations or historical snow depth climatology. After screening snow from non-snow surface targets (water bodies [including freeze/thaw state], rainfall, high altitude plateau regions [e.g. Tibetan plateau]), moderate and shallow snow depths are estimated by minimizing the difference between Dense Media Radiative Transfer model estimates (Tsang et al., 2000; Picard et al., 2011) and AMSR2 Tb observations to retrieve SWE and SD. Parameterization of the model combines a parsimonious snow grain size and density approach originally developed by Kelly et al. (2003). Evaluation of the SMSA performance is achieved using in situ snow depth data from a variety of standard and experiment data sources. Results presented from winter seasons 2012-13 to 2016-17 illustrate the improved performance of the new approach in comparison with the baseline AMSR2 algorithm estimates and approach the performance of the model assimilation-based approach of GlobSnow. Given the variation in estimation power of SWE by different land surface/climate models and selected satellite-derived passive microwave approaches, SMSA provides SWE estimates that are independent of real or near real-time in situ and model data.

Shear-Wave Elastography for the Preoperative Risk Stratification of Follicular-patterned Lesions of the Thyroid: Diagnostic Accuracy and Optimal Measurement Plane.

PubMed

Samir, Anthony E; Dhyani, Manish; Anvari, Arash; Prescott, Jason; Halpern, Elkan F; Faquin, William C; Stephen, Antonia

2015-11-01

To evaluate the diagnostic accuracy of shear-wave elastography (SWE) for the diagnosis of malignancy in follicular lesions and to identify the optimal SWE measurement plane. The institutional review board approved this HIPAA-compliant, single-institution, prospective pilot study. Subjects scheduled for surgery after a previous fine-needle aspiration report of "atypia of undetermined significance" or "follicular lesion of undetermined significance," "suspicion for follicular neoplasm," or "suspicion for Hurthle cell neoplasm," were enrolled after obtaining informed consent. Subjects underwent conventional ultrasonography (US), Doppler evaluation, and SWE preoperatively, and their predictive value for thyroid malignancy was evaluated relative to the reference standard of surgical pathologic findings. Thirty-five patients (12 men, 23 women) with a mean age of 55 years (range, 23-85 years) and a fine-needle aspiration diagnosis of atypia of undetermined significance or follicular lesion of undetermined significance (n = 16), suspicion for follicular neoplasm (n = 14), and suspicion for Hurthle cell neoplasm (n = 5) were enrolled in the study. Male sex was a statistically significant (P = .02) predictor of malignancy, but age was not. No sonographic morphologic parameter, including nodule size, microcalcification, macrocalcification, halo sign, taller than wide dimension, or hypoechogenicity, was associated with malignancy. Similarly, no Doppler feature, including intranodular vascularity, pulsatility index, resistive index, or peak-systolic velocity, was associated with malignancy. Higher median SWE tissue Young modulus estimates from the transverse insonation plane were associated with malignancy, yielding an area under the receiver operating characteristic curve of 0.81 (95% confidence interval: 0.62, 1.00) for differentiation of malignant from benign nodules. At a cutoff value of 22.3 kPa, sensitivity, specificity, positive predictive value, and negative predictive value of 82%, 88%, 75%, and 91%, respectively, were observed. This prospective pilot study indicates that SWE may be a valuable tool in preoperative malignancy risk assessment of follicular-patterned thyroid nodules. © RSNA, 2015

Smart sensing surveillance system

NASA Astrophysics Data System (ADS)

Hsu, Charles; Chu, Kai-Dee; O'Looney, James; Blake, Michael; Rutar, Colleen

2010-04-01

An effective public safety sensor system for heavily-populated applications requires sophisticated and geographically-distributed infrastructures, centralized supervision, and deployment of large-scale security and surveillance networks. Artificial intelligence in sensor systems is a critical design to raise awareness levels, improve the performance of the system and adapt to a changing scenario and environment. In this paper, a highly-distributed, fault-tolerant, and energy-efficient Smart Sensing Surveillance System (S4) is presented to efficiently provide a 24/7 and all weather security operation in crowded environments or restricted areas. Technically, the S4 consists of a number of distributed sensor nodes integrated with specific passive sensors to rapidly collect, process, and disseminate heterogeneous sensor data from near omni-directions. These distributed sensor nodes can cooperatively work to send immediate security information when new objects appear. When the new objects are detected, the S4 will smartly select the available node with a Pan- Tilt- Zoom- (PTZ) Electro-Optics EO/IR camera to track the objects and capture associated imagery. The S4 provides applicable advanced on-board digital image processing capabilities to detect and track the specific objects. The imaging detection operations include unattended object detection, human feature and behavior detection, and configurable alert triggers, etc. Other imaging processes can be updated to meet specific requirements and operations. In the S4, all the sensor nodes are connected with a robust, reconfigurable, LPI/LPD (Low Probability of Intercept/ Low Probability of Detect) wireless mesh network using Ultra-wide band (UWB) RF technology. This UWB RF technology can provide an ad-hoc, secure mesh network and capability to relay network information, communicate and pass situational awareness and messages. The Service Oriented Architecture of S4 enables remote applications to interact with the S4 network and use the specific presentation methods. In addition, the S4 is compliant with Open Geospatial Consortium - Sensor Web Enablement (OGC-SWE) standards to efficiently discover, access, use, and control heterogeneous sensors and their metadata. These S4 capabilities and technologies have great potential for both military and civilian applications, enabling highly effective security support tools for improving surveillance activities in densely crowded environments. The S4 system is directly applicable to solutions for emergency response personnel, law enforcement, and other homeland security missions, as well as in applications requiring the interoperation of sensor networks with handheld or body-worn interface devices.

Gpm Level 1 Science Requirements: Science and Performance Viewed from the Ground

NASA Technical Reports Server (NTRS)

Petersen, W.; Kirstetter, P.; Wolff, D.; Kidd, C.; Tokay, A.; Chandrasekar, V.; Grecu, M.; Huffman, G.; Jackson, G. S.

2016-01-01

GPM meets Level 1 science requirements for rain estimation based on the strong performance of its radar algorithms. Changes in the V5 GPROF algorithm should correct errors in V4 and will likely resolve GPROF performance issues relative to L1 requirements. L1 FOV Snow detection largely verified but at unknown SWE rate threshold (likely < 0.5 –1 mm/hr/liquid equivalent). Ongoing work to improve SWE rate estimation for both satellite and GV remote sensing.

A Comprehensive Web-Based Patient Information Environment

DTIC Science & Technology

2001-10-25

hospitals. Keywords - I. INTRODUCTION This paper describes a comprehensive, web-enabled, patient - centric medical information system called PiRiLiS...clinically focused. The system was found to reduce time for medical administration. The ability to view the entire patient record at anytime, anywhere in...Abstract- The paper describes a new type of medical information environment which is fully web-enabled. The system can handle any type medical

DISTANT EARLY WARNING SYSTEM for Tsunamis - A wide-area and multi-hazard approach

NASA Astrophysics Data System (ADS)

Hammitzsch, Martin; Lendholt, Matthias; Wächter, Joachim

2010-05-01

The DEWS (Distant Early Warning System) [1] project, funded under the 6th Framework Programme of the European Union, has the objective to create a new generation of interoperable early warning systems based on an open sensor platform. This platform integrates OGC [2] SWE [3] compliant sensor systems for the rapid detection of hazardous events, like earthquakes, sea level anomalies, ocean floor occurrences, and ground displacements in the case of tsunami early warning. Based on the upstream information flow DEWS focuses on the improvement of downstream capacities of warning centres especially by improving information logistics for effective and targeted warning message aggregation for a multilingual environment. Multiple telecommunication channels will be used for the dissemination of warning messages. Wherever possible, existing standards have been integrated. The Command and Control User Interface (CCUI), a rich client application based on Eclipse RCP (Rich Client Platform) [4] and the open source GIS uDig [5], integrates various OGC services. Using WMS (Web Map Service) [6] and WFS (Web Feature Service) [7] spatial data are utilized to depict the situation picture and to integrate a simulation system via WPS (Web Processing Service) [8] to identify affected areas. Warning messages are compiled and transmitted in the OASIS [9] CAP (Common Alerting Protocol) [10] standard together with addressing information defined via EDXL-DE (Emergency Data Exchange Language - Distribution Element) [11]. Internal interfaces are realized with SOAP [12] web services. Based on results of GITEWS [13] - in particular the GITEWS Tsunami Service Bus [14] - the DEWS approach provides an implementation for tsunami early warning systems but other geological paradigms are going to follow, e.g. volcanic eruptions or landslides. Therefore in future also multi-hazard functionality is conceivable. The specific software architecture of DEWS makes it possible to dock varying sensors to the system and to extend the CCUI with hazard specific functionality. The presentation covers the DEWS project, the system architecture and the CCUI in conjunction with details of information logistics. The DEWS Wide Area Centre connecting national centres to allow the international communication and warning exchange is presented also. REFERENCES: [1] DEWS, www.dews-online.org [2] OGC, www.opengeospatial.org [3] SWE, www.opengeospatial.org/projects/groups/sensorweb [4] Eclipse RCP, www.eclipse.org/home/categories/rcp.php [5] uDig, udig.refractions.net [6] WMS, www.opengeospatial.org/standards/wms [7] WFS, www.opengeospatial.org/standards/wfs [8] WPS, www.opengeospatial.org/standards/wps [9] OASIS, www.oasis-open.org [10] CAP, www.oasis-open.org/specs/#capv1.1 [11] EDXL-DE, www.oasis-open.org/specs/#edxlde-v1.0 [12] SOAP, www.w3.org/TR/soap [13] GITEWS (German Indonesian Tsunami Early Warning System) is a project of the German Federal Government to aid the recon¬struction of the tsunami-prone Indian Ocean region, www.gitews.org [14] The Tsunami Service Bus is the GITEWS sensor system integration platform offering standardised services for the detection and monitoring of tsunamis

Using geostatistical methods to estimate snow water equivalence distribution in a mountain watershed

USGS Publications Warehouse

Balk, B.; Elder, K.; Baron, Jill S.

1998-01-01

Knowledge of the spatial distribution of snow water equivalence (SWE) is necessary to adequately forecast the volume and timing of snowmelt runoff.  In April 1997, peak accumulation snow depth and density measurements were independently taken in the Loch Vale watershed (6.6 km2), Rocky Mountain National Park, Colorado.  Geostatistics and classical statistics were used to estimate SWE distribution across the watershed.  Snow depths were spatially distributed across the watershed through kriging interpolation methods which provide unbiased estimates that have minimum variances.  Snow densities were spatially modeled through regression analysis.  Combining the modeled depth and density with snow-covered area (SCA produced an estimate of the spatial distribution of SWE.  The kriged estimates of snow depth explained 37-68% of the observed variance in the measured depths.  Steep slopes, variably strong winds, and complex energy balance in the watershed contribute to a large degree of heterogeneity in snow depth.

Effects of Changing Climate During the Snow Ablation Season on Seasonal Streamflow Forecasts

NASA Astrophysics Data System (ADS)

Gutzler, D. S.; Chavarria, S. B.

2017-12-01

Seasonal forecasts of total surface runoff (Q) in snowmelt-dominated watersheds derive most of their prediction skill from the historical relationship between late winter snowpack (SWE) and subsequent snowmelt runoff. Across the western US, however, the relationship between SWE and Q is weakening as temperatures rise. We describe the effects of climate variability and change during the springtime snow ablation season on water supply outlooks (forecasts of Q) for southwestern rivers. As snow melts earlier, the importance of post-snow rainfall increases: interannual variability of spring season precipitation accounts for an increasing fraction of the variability of Q in recent decades. The results indicate that improvements to the skill of S2S forecasts of spring season temperature and precipitation would contribute very significantly to water supply outlooks that are now based largely on observed SWE. We assess this hypothesis using historical data from several snowpack-dominated basins in the American Southwest (Rio Grande, Pecos, and Gila Rivers) which are undergoing rapid climate change.

Improving biodegradability of soil washing effluents using anodic oxidation.

PubMed

Carboneras, María Belén; Cañizares, Pablo; Rodrigo, Manuel Andrés; Villaseñor, José; Fernandez-Morales, Francisco Jesus

2018-03-01

In this work, a combination of electrochemical and biological technologies is proposed to remove clopyralid from Soil Washing Effluents (SWE). Firstly, soil washing was carried out to extract clopyralid from soil. After that, four different anodes-Ir-MMO, Ru-MMO, pSi-BDD and Carbon Felt (CF)-were evaluated in order to increase the biodegradability of the SWE. CF was selected because was the only one able to transform the pesticide to a more biodegradable compounds without completely mineralizing it. Finally, biological oxidation tests were performed to determine the aerobic biodegradability of the SWE generated. From the obtained results, it was observed that at the beginning of the electrolysis the toxicity slightly increased and the biodegradability decreases. However, for electric current charges over 2.5 A·h dm -3 the toxicity drastically decreased, showing an EC 50 of 143 mg L -1 , and the BOD 5 /COD ratio increased from 0.02 to 0.23. Copyright © 2017 Elsevier Ltd. All rights reserved.

IN VIVO MEASURES OF SHEAR WAVE SPEED AS A PREDICTOR OF TENDON ELASTICITY AND STRENGTH

PubMed Central

Martin, Jack A.; Biedrzycki, Adam H.; Lee, Kenneth S.; DeWall, Ryan J.; Brounts, Sabrina H.; Murphy, William L.; Markel, Mark D.; Thelen, Darryl G.

2015-01-01

The purpose of this study was to assess the potential for ultrasound shear wave elastography (SWE) to assess tissue elasticity and ultimate stress in both intact and healing tendons. The lateral gastrocnemius (Achilles) tendons of 41 New Zealand white rabbits were surgically severed and repaired with growth factor coated sutures. SWE imaging was used to measure shear wave speed (SWS) in both the medial and lateral tendons pre-surgery, and at 2 and 4 weeks post-surgery. Rabbits were euthanized at 4 weeks, and both medial and lateral tendons underwent mechanical testing to failure. SWS significantly (p<0.001) decreased an average of 17% between the intact and post-surgical state across all tendons. SWS was significantly (p<0.001) correlated with both the tendon elastic modulus (r = 0.52) and ultimate stress (r = 0.58). Thus, ultrasound SWE is a potentially promising noninvasive technology for quantitatively assessing the mechanical integrity of pre-operative and post-operative tendons. PMID:26215492

Post-Web 2.0 Pedagogy: From Student-Generated Content to International Co-Production Enabled by Mobile Social Media

ERIC Educational Resources Information Center

Cochrane, Thomas; Antonczak, Laurent; Wagner, Daniel

2013-01-01

The advent of web 2.0 has enabled new forms of collaboration centred upon user-generated content, however, mobile social media is enabling a new wave of social collaboration. Mobile devices have disrupted and reinvented traditional media markets and distribution: iTunes, Google Play and Amazon now dominate music industry distribution channels,…

Small Water Enterprise in Rural Rwanda: Business Development and Year-One Performance Evaluation of Nine Water Kiosks at Health Care Facilities

PubMed Central

Huttinger, Alexandra; Brunson, Laura; Roha, Kristin; Ngirimpuhwe, Providence; Mfura, Leodomir; Kayigamba, Felix; Ciza, Philbert

2017-01-01

Small water enterprises (SWEs) have lower capital expenditures than centralized systems, offering decentralized solutions for rural markets. This study evaluated SWEs in rural Rwanda, where nine health care facilities (HCF) owned and operated water kiosks supplying water from onsite water treatment systems (WTS). SWEs were monitored for 12 months. Spearman’s Rank Correlation Coefficient (rs) was used to evaluate correlations between demand for kiosk water and community characteristics, and between kiosk profit and factors influencing the cost model. On average, SWEs distributed 15,300 L/month. One SWE ran at a loss, four had profit margins of ≤10% and four had profit margins of 45–75%. Factors influencing SWE performance were intermittent water supply (87% of SWE closures were due to water shortage), consumer demand (demand was high where populations already used improved water sources (rs = 0.81, p = 0.02)), price sensitivity (demand was lower where SWEs had high prices (rs = −0.65, p = 0.08)), and production cost (water utility tariffs negatively impacted SWE profits (rs = −0.52, p < 0.01)). Sustainability was more favorable in circumstances where recovery of capital expenditures was not expected, and the demand for treated water was sufficient to fund operational expenditures. Future research is needed to assess the extent to which kiosk revenue can support ongoing operational costs of WTS and kiosks both at HCF and in other contexts. PMID:29258167

Small Water Enterprise in Rural Rwanda: Business Development and Year-One Performance Evaluation of Nine Water Kiosks at Health Care Facilities.

PubMed

Huttinger, Alexandra; Brunson, Laura; Moe, Christine L; Roha, Kristin; Ngirimpuhwe, Providence; Mfura, Leodomir; Kayigamba, Felix; Ciza, Philbert; Dreibelbis, Robert

2017-12-16

Small water enterprises (SWEs) have lower capital expenditures than centralized systems, offering decentralized solutions for rural markets. This study evaluated SWEs in rural Rwanda, where nine health care facilities (HCF) owned and operated water kiosks supplying water from onsite water treatment systems (WTS). SWEs were monitored for 12 months. Spearman's Rank Correlation Coefficient (r s ) was used to evaluate correlations between demand for kiosk water and community characteristics, and between kiosk profit and factors influencing the cost model. On average, SWEs distributed 15,300 L/month. One SWE ran at a loss, four had profit margins of ≤10% and four had profit margins of 45-75%. Factors influencing SWE performance were intermittent water supply (87% of SWE closures were due to water shortage), consumer demand (demand was high where populations already used improved water sources (r s = 0.81, p = 0.02)), price sensitivity (demand was lower where SWEs had high prices (r s = -0.65, p = 0.08)), and production cost (water utility tariffs negatively impacted SWE profits (r s = -0.52, p < 0.01)). Sustainability was more favorable in circumstances where recovery of capital expenditures was not expected, and the demand for treated water was sufficient to fund operational expenditures. Future research is needed to assess the extent to which kiosk revenue can support ongoing operational costs of WTS and kiosks both at HCF and in other contexts.

A New Operational Snow Retrieval Algorithm Applied to Historical AMSR-E Brightness Temperatures

NASA Technical Reports Server (NTRS)

Tedesco, Marco; Jeyaratnam, Jeyavinoth

2016-01-01

Snow is a key element of the water and energy cycles and the knowledge of spatio-temporal distribution of snow depth and snow water equivalent (SWE) is fundamental for hydrological and climatological applications. SWE and snow depth estimates can be obtained from spaceborne microwave brightness temperatures at global scale and high temporal resolution (daily). In this regard, the data recorded by the Advanced Microwave Scanning Radiometer-Earth Orbiting System (EOS) (AMSR-E) onboard the National Aeronautics and Space Administration's (NASA) AQUA spacecraft have been used to generate operational estimates of SWE and snow depth, complementing estimates generated with other microwave sensors flying on other platforms. In this study, we report the results concerning the development and assessment of a new operational algorithm applied to historical AMSR-E data. The new algorithm here proposed makes use of climatological data, electromagnetic modeling and artificial neural networks for estimating snow depth as well as a spatio-temporal dynamic density scheme to convert snow depth to SWE. The outputs of the new algorithm are compared with those of the current AMSR-E operational algorithm as well as in-situ measurements and other operational snow products, specifically the Canadian Meteorological Center (CMC) and GlobSnow datasets. Our results show that the AMSR-E algorithm here proposed generally performs better than the operational one and addresses some major issues identified in the spatial distribution of snow depth fields associated with the evolution of effective grain size.

Web-Altairis: An Internet-Enabled Ground System

NASA Technical Reports Server (NTRS)

Miller, Phil; Coleman, Jason; Gemoets, Darren; Hughes, Kevin

2000-01-01

This paper describes Web-Altairis, an Internet-enabled ground system software package funded by the Advanced Automation and Architectures Branch (Code 588) of NASA's Goddard Space Flight Center. Web-Altairis supports the trend towards "lights out" ground systems, where the control center is unattended and problems are resolved by remote operators. This client/server software runs on most popular platforms and provides for remote data visualization using the rich functionality of the VisAGE toolkit. Web-Altairis also supports satellite commanding over the Internet. This paper describes the structure of Web-Altairis and VisAGE, the underlying technologies, the provisions for security, and our experiences in developing and testing the software.

Management reporting on the Web.

PubMed Central

Narayanan, G.; McHolm, G.; Jones, D. T.

2000-01-01

Driven by easy-to-use World Wide Web technology and new information integration concepts that have proven their worth in business and industry, online management reporting is now becoming an important strategy for improving operational performance in health care organizations. In this article, we provide an overview of these new information management concepts and describe our experience in planning and executing an enterprise-wide Web-enabled management reporting initiative. We also offer an inventory of the key organizational capacities that we found essential for developing and sustaining Web-enabled reporting services for health care managers. PMID:11079955

Relating Satellite Gravimetry to Global Snow Water Equivalent

NASA Astrophysics Data System (ADS)

Baumann, S. C.

2017-12-01

The gravimetric satellites GRACE measure changes of Earth's mass. The data mainly show changes in total water storage (TWS) but cannot distinguish between different sources. Hence, other data are necessary to extract the different compartments. Due to the spatial resolution of 200,000 km² and an accuracy of 2.5 cm w.e., other global products are compared with GRACE. In this study, the hydrological model WGHM and the land surface model GLDAS were used. All data were pre-processed in the same way as the GRACE data. Data were converted into monthly 1° grid values. Time is from 01/2003 to 12/2013 with a total of 131 months. The aim of the study was to extract SWE from GRACE as snow is an important factor for permafrost development. The main assumption is that changes in TWS can be linked to changes in SWE if SWE is the dominant compartment of TWS or if SWE changes proportionally with TWS. The study area were two river catchments in North America (Mackenzie, Yukon) and three in Russia (Lena, Ob, Yenisei). TWS as SWE from both models were correlated with GRACE as with each other (1) pixel and (2) catchment based. The (1) pixel based correlation used absolute values and the (2) catchment based correlation the sum of monthly anomalies from the total mean for each catchment. Initial results of the (1) pixel based correlation show a very high correlation of the WGHM vs. GLDAS data. The correlation of GRACE vs. WGHM is higher compared to the correlation between GRACE vs. GLDAS. The (2) correlation of the catchment data was higher than 0.74 in all river catchments for the WGHM vs. GLDAS data (TWS and SWE). As for the pixel based correlation, values for the correlation of GRACE vs. WGHM are higher compared to GRACE vs. GLDAS in all river catchments. Summed monthly WGHM anomalies of the catchments showed a uniform periodically annual pattern. GRACE data showed the same pattern between 2006 and 2011 but had more peaks in the beginning and the end of the study period. Therefore, a second correlation was performed for this uniform shorter period. The (1) pixel based correlation of GRACE vs. the two models had higher values in the river catchments in North America and lower values in Russia. This pattern was more pronounced in the correlation of GRACE vs. WGHM. The (2) catchment based correlation of the shorter period improved for nearly all correlation pairs and river catchments.

Antibody-based in vivo PET imaging detects amyloid-β reduction in Alzheimer transgenic mice after BACE-1 inhibition.

PubMed

Meier, Silvio R; Syvänen, Stina; Hultqvist, Greta; Fang, Xiaotian T; Roshanbin, Sahar; Lannfelt, Lars; Neumann, Ulf; Sehlin, Dag

2018-05-31

Positron emission tomography (PET) used for visualizing amyloid-β (Aβ) pathology has become an important tool for specific clinical diagnosis of Alzheimer's disease (AD). However, all available amyloid PET radioligands, such as [ 11 C]PiB, reflect levels of insoluble Aβ plaques, but do not capture soluble and protofibrillar Aβ forms. When measured with current PET ligands, the plaque load appears to be fairly static during clinical stages of AD, and may not be affected by Aβ reducing treatments. The aim of the present study was to investigate if a novel PET radioligand, based on an antibody directed towards soluble aggregates of Aβ, could be used to detect changes in Aβ levels during disease progression and after treatment with a β-secretase (BACE-1) inhibitor. Methods: One set of transgenic mice (tg-ArcSwe, model of Aβ pathology) aged between 7 and 16 months were PET scanned with the Aβ protofibril selective radioligand [ 124 I]RmAb158-scFv8D3 to follow progression of Aβ pathology in the brain. A second set of tg-ArcSwe mice, aged 10 months, were treated with BACE-1 inhibitor NB-360 for 3 months and compared to an untreated control group. A set of 10 months old tg-ArcSwe mice also underwent PET scanning, acting as a baseline group. Brain tissue was isolated after PET to determine levels of Aβ by ELISA and immunohistochemistry. Results: Concentration of [ 124 I]RmAb158-scFv8D3 in tg-ArcSwe mice, measured in vivo with PET, increased with age and corresponded well with ex vivo autoradiography and Aβ immunohistochemistry. Tg-ArcSwe mice treated with NB-360 showed significantly lower in vivo PET signals than untreated animals, and were similar to the baseline 10 month old animals. The decreased [ 124 I]RmAb158-scFv8D3 concentrations in NB-360 treated mice, quantified with PET, corresponded well with decreased Aβ levels measured in post mortem brain. Conclusion: A number of treatments for AD are currently studied in phase 2 and 3 clinical trials but there are limited possibilities to study their effects on the important, non-fibrillar Aβ forms in vivo. This study demonstrates the ability of the Aβ protofibril selective radioligand [ 124 I]RmAb158-scFv8D3 to follow disease progression and detect treatment effects with PET imaging in tg-ArcSwe mice. Copyright © 2018 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Evaluating uncertainties in modelling the snow hydrology of the Fraser River Basin, British Columbia, Canada

NASA Astrophysics Data System (ADS)

Islam, Siraj Ul; Déry, Stephen J.

2017-03-01

This study evaluates predictive uncertainties in the snow hydrology of the Fraser River Basin (FRB) of British Columbia (BC), Canada, using the Variable Infiltration Capacity (VIC) model forced with several high-resolution gridded climate datasets. These datasets include the Canadian Precipitation Analysis and the thin-plate smoothing splines (ANUSPLIN), North American Regional Reanalysis (NARR), University of Washington (UW) and Pacific Climate Impacts Consortium (PCIC) gridded products. Uncertainties are evaluated at different stages of the VIC implementation, starting with the driving datasets, optimization of model parameters, and model calibration during cool and warm phases of the Pacific Decadal Oscillation (PDO). The inter-comparison of the forcing datasets (precipitation and air temperature) and their VIC simulations (snow water equivalent - SWE - and runoff) reveals widespread differences over the FRB, especially in mountainous regions. The ANUSPLIN precipitation shows a considerable dry bias in the Rocky Mountains, whereas the NARR winter air temperature is 2 °C warmer than the other datasets over most of the FRB. In the VIC simulations, the elevation-dependent changes in the maximum SWE (maxSWE) are more prominent at higher elevations of the Rocky Mountains, where the PCIC-VIC simulation accumulates too much SWE and ANUSPLIN-VIC yields an underestimation. Additionally, at each elevation range, the day of maxSWE varies from 10 to 20 days between the VIC simulations. The snow melting season begins early in the NARR-VIC simulation, whereas the PCIC-VIC simulation delays the melting, indicating seasonal uncertainty in SWE simulations. When compared with the observed runoff for the Fraser River main stem at Hope, BC, the ANUSPLIN-VIC simulation shows considerable underestimation of runoff throughout the water year owing to reduced precipitation in the ANUSPLIN forcing dataset. The NARR-VIC simulation yields more winter and spring runoff and earlier decline of flows in summer due to a nearly 15-day earlier onset of the FRB springtime snowmelt. Analysis of the parametric uncertainty in the VIC calibration process shows that the choice of the initial parameter range plays a crucial role in defining the model hydrological response for the FRB. Furthermore, the VIC calibration process is biased toward cool and warm phases of the PDO and the choice of proper calibration and validation time periods is important for the experimental setup. Overall the VIC hydrological response is prominently influenced by the uncertainties involved in the forcing datasets rather than those in its parameter optimization and experimental setups.

Concept Mapping Your Web Searches: A Design Rationale and Web-Enabled Application

ERIC Educational Resources Information Center

Lee, Y.-J.

2004-01-01

Although it has become very common to use World Wide Web-based information in many educational settings, there has been little research on how to better search and organize Web-based information. This paper discusses the shortcomings of Web search engines and Web browsers as learning environments and describes an alternative Web search environment…

Electrical Cabinet Fire Extinguishment Testing

DTIC Science & Technology

2014-12-01

Ins t series thes for the majo of soot (alth lenses in the arbon steel, re exposure ests. of each me cabinet (at aried with h above the above...ressure in th g pre-burn, 1 2 titute of Swe et was monit presented in Figure 19. re measured ssure sensor . be made con ssure in the e reduced the e...preven e of the extin r than the ov r pressure in opped to a n titute of Swe ra 25, was s ting pre-fire he major dif soot (despit exposure. in

Web-Enabled Systems for Student Access.

ERIC Educational Resources Information Center

Harris, Chad S.; Herring, Tom

1999-01-01

California State University, Fullerton is developing a suite of server-based, Web-enabled applications that distribute the functionality of its student information system software to external customers without modifying the mainframe applications or databases. The cost-effective, secure, and rapidly deployable business solution involves using the…

78 FR 23566 - Agency Information Collection Activities: Proposed Collection; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-19

... utility of the proposed information collection for the proper performance of the agency's functions; (2... Information Collection: Consolidated Renal Operations in a Web Enabled Network (CROWNWeb) Third-party Submission Authorization Form Use: The Consolidated Renal Operations in a Web Enabled Network (CROWNWeb...

The Virtual Learning Commons (VLC): Enabling Co-Innovation Across Disciplines

NASA Astrophysics Data System (ADS)

Pennington, D. D.; Gandara, A.; Del Rio, N.

2014-12-01

A key challenge for scientists addressing grand-challenge problems is identifying, understanding, and integrating potentially relevant methods, models and tools that that are rapidly evolving in the informatics community. Such tools are essential for effectively integrating data and models in complex research projects, yet it is often difficult to know what tools are available and it is not easy to understand or evaluate how they might be used in a given research context. The goal of the National Science Foundation-funded Virtual Learning Commons (VLC) is to improve awareness and understanding of emerging methodologies and technologies, facilitate individual and group evaluation of these, and trace the impact of innovations within and across teams, disciplines, and communities. The VLC is a Web-based social bookmarking site designed specifically to support knowledge exchange in research communities. It is founded on well-developed models of technology adoption, diffusion of innovation, and experiential learning. The VLC makes use of Web 2.0 (Social Web) and Web 3.0 (Semantic Web) approaches. Semantic Web approaches enable discovery of potentially relevant methods, models, and tools, while Social Web approaches enable collaborative learning about their function. The VLC is under development and the first release is expected Fall 2014.

Critical Issues of Web-Enabled Technologies in Modern Organizations.

ERIC Educational Resources Information Center

Khosrow-Pour, Mehdi; Herman, Nancy

2001-01-01

Discusses results of a Delphi study that explored issues related to the utilization and management of Web-enabled technologies by modern organizations. Topics include bandwidth restrictions; security; data integrity; inadequate search facilities; system incompatibilities; failure to adhere to standards; email; use of metadata; privacy and…

Knowledge base and sensor bus messaging service architecture for critical tsunami warning and decision-support

NASA Astrophysics Data System (ADS)

Sabeur, Z. A.; Wächter, J.; Middleton, S. E.; Zlatev, Z.; Häner, R.; Hammitzsch, M.; Loewe, P.

2012-04-01

The intelligent management of large volumes of environmental monitoring data for early tsunami warning requires the deployment of robust and scalable service oriented infrastructure that is supported by an agile knowledge-base for critical decision-support In the TRIDEC project (TRIDEC 2010-2013), a sensor observation service bus of the TRIDEC system is being developed for the advancement of complex tsunami event processing and management. Further, a dedicated TRIDEC system knowledge-base is being implemented to enable on-demand access to semantically rich OGC SWE compliant hydrodynamic observations and operationally oriented meta-information to multiple subscribers. TRIDEC decision support requires a scalable and agile real-time processing architecture which enables fast response to evolving subscribers requirements as the tsunami crisis develops. This is also achieved with the support of intelligent processing services which specialise in multi-level fusion methods with relevance feedback and deep learning. The TRIDEC knowledge base development work coupled with that of the generic sensor bus platform shall be presented to demonstrate advanced decision-support with situation awareness in context of tsunami early warning and crisis management.

The Semantic Web in Teacher Education

ERIC Educational Resources Information Center

Czerkawski, Betül Özkan

2014-01-01

The Semantic Web enables increased collaboration among computers and people by organizing unstructured data on the World Wide Web. Rather than a separate body, the Semantic Web is a functional extension of the current Web made possible by defining relationships among websites and other online content. When explicitly defined, these relationships…

Accuracy assessment of a net radiation and temperature index snowmelt model using ground observations of snow water equivalent in an alpine basin

NASA Astrophysics Data System (ADS)

Molotch, N. P.; Painter, T. H.; Bales, R. C.; Dozier, J.

2003-04-01

In this study, an accumulated net radiation / accumulated degree-day index snowmelt model was coupled with remotely sensed snow covered area (SCA) data to simulate snow cover depletion and reconstruct maximum snow water equivalent (SWE) in the 19.1-km2 Tokopah Basin of the Sierra Nevada, California. Simple net radiation snowmelt models are attractive for operational snowmelt runoff forecasts as they are computationally inexpensive and have low input requirements relative to physically based energy balance models. The objective of this research was to assess the accuracy of a simple net radiation snowmelt model in a topographically heterogeneous alpine environment. Previous applications of net radiation / temperature index snowmelt models have not been evaluated in alpine terrain with intensive field observations of SWE. Solar radiation data from two meteorological stations were distributed using the topographic radiation model TOPORAD. Relative humidity and temperature data were distributed based on the lapse rate calculated between three meteorological stations within the basin. Fractional SCA data from the Landsat Enhanced Thematic Mapper (5 acquisitions) and the Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) (2 acquisitions) were used to derive daily SCA using a linear regression between acquisition dates. Grain size data from AVIRIS (4 acquisitions) were used to infer snow surface albedo and interpolated linearly with time to derive daily albedo values. Modeled daily snowmelt rates for each 30-m pixel were scaled by the SCA and integrated over the snowmelt season to obtain estimates of maximum SWE accumulation. Snow surveys consisting of an average of 335 depth measurements and 53 density measurements during April, May and June, 1997 were interpolated using a regression tree / co-krig model, with independent variables of average incoming solar radiation, elevation, slope and maximum upwind slope. The basin was clustered into 7 elevation / average-solar-radiation zones for SWE accuracy assessment. Model simulations did a poor job at estimating the spatial distribution of SWE. Basin clusters where the solar radiative flux dominated the melt flux were simulated more accurately than those dominated by the turbulent fluxes or the longwave radiative flux.

Red Seaweeds Sarcodiotheca gaudichaudii and Chondrus crispus down Regulate Virulence Factors of Salmonella Enteritidis and Induce Immune Responses in Caenorhabditis elegans.

PubMed

Kulshreshtha, Garima; Borza, Tudor; Rathgeber, Bruce; Stratton, Glenn S; Thomas, Nikhil A; Critchley, Alan; Hafting, Jeff; Prithiviraj, Balakrishnan

2016-01-01

Red seaweeds are a rich source of unique bioactive compounds and secondary metabolites that are known to improve human and animal health. S. Enteritidis is a broad range host pathogen, which contaminates chicken and poultry products that end into the human food chain. Worldwide, Salmonella outbreaks have become an important economic and public health concern. Moreover, the development of resistance in Salmonella serovars toward multiple drugs highlights the need for alternative control strategies. This study evaluated the antimicrobial property of red seaweeds extracts against Salmonella Enteritidis using the Caenorhabditis elegans infection model. Six red seaweed species were tested for their antimicrobial activity against S. Enteritidis and two, Sarcodiotheca gaudichaudii (SG) and Chondrus crispus (CC), were found to exhibit such properties. Spread plate assay revealed that SG and CC (1%, w/v) significantly reduced the growth of S. Enteritidis. Seaweed water extracts (SWE) of SG and CC, at concentrations from 0.4 to 2 mg/ml, significantly reduced the growth of S. Enteritidis (log CFU 4.5-5.3 and log 5.7-6.0, respectively). However, methanolic extracts of CC and SG did not affect the growth of S. Enteritidis. Addition of SWE (0.2 mg/ml, CC and SG) significantly decreased biofilm formation and reduced the motility of S. Enteritidis. Quantitative real-time PCR analyses showed that SWE (CC and SG) suppressed the expression of quorum sensing gene sdiA and of Salmonella Pathogenesis Island-1 (SPI-1) associated genes sipA and invF, indicating that SWE might reduce the invasion of S. Enteritidis in the host by attenuating virulence factors. Furthermore, CC and SG water extracts significantly improved the survival of infected C. elegans by impairing the ability of S. Enteritidis to colonize the digestive tract of the nematode and by enhancing the expression of C. elegans immune responsive genes. As the innate immune response pathways of C. elegans and mammals show a high degree of conservation, these results suggest that these SWE may also impart beneficial effects on animal and human health.

Real-Time Shear Wave versus Transient Elastography for Predicting Fibrosis: Applicability, and Impact of Inflammation and Steatosis. A Non-Invasive Comparison

PubMed Central

Poynard, Thierry; Pham, Tam; Perazzo, Hugo; Munteanu, Mona; Luckina, Elena; Elaribi, Djamel; Ngo, Yen; Bonyhay, Luminita; Seurat, Noemie; Legroux, Muriel; Ngo, An; Deckmyn, Olivier; Thabut, Dominique; Ratziu, Vlad; Lucidarme, Olivier

2016-01-01

Background and Aims Real-time shear wave elastography (2D-SWE) is a two-dimensional transient elastography and a competitor as a biomarker of liver fibrosis in comparison with the standard reference transient elastography by M probe (TE-M). The aims were to compare several criteria of applicability, and to assess inflammation and steatosis impact on elasticity values, two unmet needs. Methods We took FibroTest as the fibrosis reference and ActiTest and SteatoTest as quantitative estimates of inflammation and steatosis. After standardization of estimates, analyses used curve fitting, quantitative Lin concordance coefficient [LCC], and multivariate logistic regression. Results A total of 2,251 consecutive patients were included. We validated the predetermined 0.2 kPa cut-off as a too low minimal elasticity value identifying not-reliable 2D-SWE results (LCC with FibroTest = 0.0281[-0.119;0.175]. Other criteria, elasticity CV, body mass index and depth of measures were not sufficiently discriminant. The applicability of 2D-SWE (95%CI) 89.6%(88.2–90.8), was significantly higher than that of TE, 85.6%(84.0–87.0; P<0.0001). In patients with non-advanced fibrosis (METAVIR F0F1F2), elasticity values estimated by 2D-SWE was less impacted by inflammation and steatosis than elasticity value estimated by TE-M: LCC (95%CI) 0.039 (0.021;0.058) vs 0.090 (0.068;0.112;P<0.01) and 0.105 (0.068;0.141) vs 0.192 (0.153;0.230; P<0.01) respectively. The three analyses methods gave similar results. Conclusions Elasticity results including very low minimal signal in the region of interest should be considered not reliable. 2D-SWE had a higher applicability than TE, the reference elastography, with less impact of inflammation and steatosis especially in patients with non-advanced fibrosis, as presumed by blood tests. Trial Registration ClinicalTrials.gov NCT01927133 PMID:27706177

Clinical acceptance testing and scanner comparison of ultrasound shear wave elastography.

PubMed

Long, Zaiyang; Tradup, Donald J; Song, Pengfei; Stekel, Scott F; Chen, Shigao; Glazebrook, Katrina N; Hangiandreou, Nicholas J

2018-03-15

Because of the rapidly growing use of ultrasound shear wave elastography (SWE) in clinical practices, there is a significant need for development of clinical physics performance assessment methods for this technology. This study aims to report two clinical medical physicists' tasks: (a) acceptance testing (AT) of SWE function on ten commercial ultrasound systems for clinical liver application and (b) comparison of SWE measurements of targets across vendors for clinical musculoskeletal application. For AT, ten GE LOGIQ E9 XDclear 2.0 scanners with ten C1-6-D and ten 9L-D transducers were studied using two commercial homogenous phantoms. Five measurements were acquired at two depths for each scanner/transducer pair by two operators. Additional tests were performed to access effects of different coupling media, phantom locations and operators. System deviations were less than 5% of group mean or three times standard deviation; therefore, all systems passed AT. A test protocol was provided based on results that no statistically significant difference was observed between using ultrasound gel and salt water for coupling, among different phantom locations, and that interoperator and intraoperator coefficient of variation was less than 3%. For SWE target measurements, two systems were compared - a Supersonic Aixplorer scanner with a SL10-2 and a SL15-4 transducer, and an abovementioned GE scanner with 9L-D transducer. Two stepped cylinders with diameters of 4.05-10.40 mm were measured both longitudinally and transaxially. Target shear wave speed quantification was performed using an in-house MATLAB program. Using the target shear wave speed deduced from phantom specs as a reference, SL15-4 performed the best at the measured depth. However, it was challenging to reliably measure a 4.05 mm target for either system. The reported test methods and results could provide important information when dealing with SWE-related tasks in the clinical environment. © 2018 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

Shear wave elastography in medullary thyroid carcinoma diagnostics.

PubMed

Dobruch-Sobczak, Katarzyna; Gumińska, Anna; Bakuła-Zalewska, Elwira; Mlosek, Krzysztof; Słapa, Rafał Z; Wareluk, Paweł; Krauze, Agnieszka; Ziemiecka, Agnieszka; Migda, Bartosz; Jakubowski, Wiesław; Dedecjus, Marek

2015-12-01

Shear wave elastography (SWE) is a modern method for the assessment of tissue stiffness. There has been a growing interest in the use of this technique for characterizing thyroid focal lesions, including preoperative diagnostics. The aim of the study was to assess the clinical usefulness of SWE in medullary thyroid carcinoma (MTC) diagnostics. A total of 169 focal lesions were identified in the study group (139 patients), including 6 MTCs in 4 patients (mean age: 45 years). B-mode ultrasound and SWE were performed using Aixplorer (SuperSonic, Aix-en-Provence), with a 4-15 MHz linear probe. The ultrasound was performed to assess the echogenicity and echostructure of the lesions, their margin, the halo sign, the height/width ratio (H/W ratio), the presence of calcifications and the vascularization pattern. This was followed by an analysis of maximum and mean Young's (E) modulus values for MTC (EmaxLR, EmeanLR) and the surrounding thyroid tissues (EmaxSR, EmeanSR), as well as mean E-values (EmeanLRz) for 2 mm region of interest in the stiffest zone of the lesion. The lesions were subject to pathological and/or cytological evaluation. The B-mode assessment showed that all MTCs were hypoechogenic, with no halo sign, and they contained micro- and/ or macrocalcifications. Ill-defined lesion margin were found in 4 out of 6 cancers; 4 out of 6 cancers had a H/W ratio > 1. Heterogeneous echostructure and type III vascularity were found in 5 out of 6 lesions. In the SWE, the mean value of EmaxLR for all of the MTCs was 89.5 kPa and (the mean value of EmaxSR for all surrounding tissues was) 39.7 kPa Mean values of EmeanLR and EmeanSR were 34.7 kPa and 24.4 kPa, respectively. The mean value of EmeanLRz was 49.2 kPa. SWE showed MTCs as stiffer lesions compared to the surrounding tissues. The lesions were qualified for fine needle aspiration biopsy based on B-mode assessment. However, the diagnostic algorithm for MTC is based on the measurement of serum calcitonin levels, B-mode ultrasound and FNAB.

Spatial properties of snow cover in the Upper Merced River Basin: implications for a distributed snow measurement network

NASA Astrophysics Data System (ADS)

Bouffon, T.; Rice, R.; Bales, R.

2006-12-01

The spatial distributions of snow water equivalent (SWE) and snow depth within a 1, 4, and 16 km2 grid element around two automated snow pillows in a forested and open- forested region of the Upper Merced River Basin (2,800 km2) of Yosemite National Park were characterized using field observations and analyzed using binary regression trees. Snow surveys occurred at the forested site during the accumulation and ablation seasons, while at the open-forest site a survey was performed only during the accumulation season. An average of 130 snow depth and 7 snow density measurements were made on each survey, within the 4 km2 grid. Snow depth was distributed using binary regression trees and geostatistical methods using the physiographic parameters (e.g. elevation, slope, vegetation, aspect). Results in the forest region indicate that the snow pillow overestimated average SWE within the 1, 4, and 16 km2 areas by 34 percent during ablation, but during accumulation the snow pillow provides a good estimate of the modeled mean SWE grid value, however it is suspected that the snow pillow was underestimating SWE. However, at the open forest site, during accumulation, the snow pillow was 28 percent greater than the mean modeled grid element. In addition, the binary regression trees indicate that the independent variables of vegetation, slope, and aspect are the most influential parameters of snow depth distribution. The binary regression tree and multivariate linear regression models explain about 60 percent of the initial variance for snow depth and 80 percent for density, respectively. This short-term study provides motivation and direction for the installation of a distributed snow measurement network to fill the information gap in basin-wide SWE and snow depth measurements. Guided by these results, a distributed snow measurement network was installed in the Fall 2006 at Gin Flat in the Upper Merced River Basin with the specific objective of measuring accumulation and ablation across topographic variables with the aim of providing guidance for future larger scale observation network designs.

Diagnostic accuracy of shear wave elastography for prediction of breast malignancy in patients with pathological nipple discharge

PubMed Central

Guo, Xiaobo; Liu, Ying; Li, Wanhu

2016-01-01

Objectives Pathological nipple discharge (PND) may indicate malignant breast lesions. As the role of shear wave elastography (SWE) in predicting these malignant lesions has not yet been evaluated, we aim to evaluate the diagnostic value of SWE for this condition. Design Prospective diagnostic accuracy study comparing a combination of qualitative and quantitative measurements of SWE (index test) to a ductoscopy and microdochectomy for histological diagnosis (reference test). Setting Fuzhou General Hospital of Nanjing military command. Participants A total of 379 patients with PND were finally included from January, 2011 to March 2014, after we screened 1084 possible candidates. All participants were evaluated through SWE, with qualitative parameters generated by Virtual Touch tissue imaging (VTI) and quantitative parameters generated by Virtual Touch tissue quantification (VTQ). All the patients were consented to receive a ductoscopy and microdochectomy for histological diagnosis, and the results were set as a reference test. Outcome measures Sensitivity and specificity of the combined VTI and VTQ of the SWE for detection of malignancy in patients with PND. Results The 379 participants presented with 404 lesions. The results of pathological examination showed that 326 (80.7%) of the 404 lesions were benign and the other 78 (19.3%) were malignant. An area under the curve of elasticity score, VTQm and VTQc, were 0.872, 0.825 and 0.857, respectively, with the corresponding cut-off point as 2.50, 2.860 m/s and 3.015 m/s, respectively. After a combination of these measurements, the sensitivity, specificity, and positive and negative predictive value (PPV and NPV), were 89.7%, 72.1%, 43.5% and 96.7%, respectively. The sensitivity analysis showed 82% of the sensitivity and 96.8% of the specificity, in which patients with no pathological findings in ductoscopy were excluded. Conclusions Ultrasonographic elastography is sensitive for patients with PND and could be used as a triage test before ductoscopy examination. Studies for further improvement of diagnostic sensitivity are warranted. PMID:26801462

Red Seaweeds Sarcodiotheca gaudichaudii and Chondrus crispus down Regulate Virulence Factors of Salmonella Enteritidis and Induce Immune Responses in Caenorhabditis elegans

PubMed Central

Kulshreshtha, Garima; Borza, Tudor; Rathgeber, Bruce; Stratton, Glenn S.; Thomas, Nikhil A.; Critchley, Alan; Hafting, Jeff; Prithiviraj, Balakrishnan

2016-01-01

Red seaweeds are a rich source of unique bioactive compounds and secondary metabolites that are known to improve human and animal health. S. Enteritidis is a broad range host pathogen, which contaminates chicken and poultry products that end into the human food chain. Worldwide, Salmonella outbreaks have become an important economic and public health concern. Moreover, the development of resistance in Salmonella serovars toward multiple drugs highlights the need for alternative control strategies. This study evaluated the antimicrobial property of red seaweeds extracts against Salmonella Enteritidis using the Caenorhabditis elegans infection model. Six red seaweed species were tested for their antimicrobial activity against S. Enteritidis and two, Sarcodiotheca gaudichaudii (SG) and Chondrus crispus (CC), were found to exhibit such properties. Spread plate assay revealed that SG and CC (1%, w/v) significantly reduced the growth of S. Enteritidis. Seaweed water extracts (SWE) of SG and CC, at concentrations from 0.4 to 2 mg/ml, significantly reduced the growth of S. Enteritidis (log CFU 4.5–5.3 and log 5.7–6.0, respectively). However, methanolic extracts of CC and SG did not affect the growth of S. Enteritidis. Addition of SWE (0.2 mg/ml, CC and SG) significantly decreased biofilm formation and reduced the motility of S. Enteritidis. Quantitative real-time PCR analyses showed that SWE (CC and SG) suppressed the expression of quorum sensing gene sdiA and of Salmonella Pathogenesis Island-1 (SPI-1) associated genes sipA and invF, indicating that SWE might reduce the invasion of S. Enteritidis in the host by attenuating virulence factors. Furthermore, CC and SG water extracts significantly improved the survival of infected C. elegans by impairing the ability of S. Enteritidis to colonize the digestive tract of the nematode and by enhancing the expression of C. elegans immune responsive genes. As the innate immune response pathways of C. elegans and mammals show a high degree of conservation, these results suggest that these SWE may also impart beneficial effects on animal and human health. PMID:27065981

Assessing the Climate Sensitivity of Cold Content and Snowmelt in Seasonal Alpine and Subalpine Snowpacks

NASA Astrophysics Data System (ADS)

Jennings, K. S.; Molotch, N. P.

2016-12-01

In cold, high-elevation sites, snowpack cold content acts as a buffer against climate warming by resisting snowmelt during periods of positive energy fluxes. To test the climate sensitivity of cold content and snowmelt, we employed the physical SNOWPACK snow model, forced with a 23-year, hourly, quality-controlled, gap-filled meteorological dataset from the Niwot Ridge Long Term Ecological Research (LTER) site in the Front Range mountains of Colorado. SNOWPACK was run at two points with seasonal snowpacks within the LTER, one in the alpine (3528 m) and one in the subalpine (3022 m). Model output was validated using snow water equivalent (SWE), snowpack temperature, and cold content data from snow pits dug near the met stations and automated SWE data from nearby SNOTEL snow pillows. Cold content accumulates primarily through additions of new snow, while negative energy fluxes—cooling through longwave emission and sublimation—play a lesser role, particularly in the deeper snowpack of the alpine. On average, the snowpack energy balance becomes positive on April 1 in the alpine and March 8 in the subalpine. Peak SWE occurs after these dates and its timing is primarily determined by the amount of precipitation received after peak cold content, with persistent snowfall delaying the main snowmelt pulse. Years with lower cold content, due to reduced precipitation and/or increased air temperature, experience an earlier positive energy balance with more melt events occurring before the date of peak SWE, which has implications for soil moisture, streamflow volume and timing, water uptake by vegetation, and microbial respiration. Synthetic warming experiments show significant cold content reductions and increased late-winter/early-spring melt as positive energy balances occur earlier in the snow season (a forward shift between 5.1 and 21.0 days per °C of warming). These results indicate cold, high-elevation sites, which are critical for water resources in the western United States, may lose their cold content buffering capacity and begin to experience stronger negative trends in SWE with increased climate warming, even as the majority of winter precipitation continues to fall as snow.

Operational and LIS-Based North American Land Data Assimilation Systems at National Centers for Environmental Prediction: Capability in Simulating Water and Energy Budget over the Western United States

NASA Astrophysics Data System (ADS)

Mitchell, K.; Xia, Y.; Ek, M. B.; Mocko, D. M.; Kumar, S.; Peters-Lidard, C. D.

2016-12-01

NLDAS is a multi-institutional collaborative project sponsored by NOAA's Climate Program Office and NASA's Terrestrial Hydrological Program. NLDAS has a long successful history of producing soil moisture, snow cover, total runoff and streamflow products via application of surface meteorology and precipitation datasets to drive four land-surface models (i.e., Noah, Mosaic, SAC, VIC). The purpose of the NLDAS system is to support numerous research and operational applications in the land modeling and water resources management communities. Since the operational NLDAS version was successfully implemented at NCEP in August 2014, NLDAS products are being used by over 5000 users annually worldwide, including academia, governmental agencies, and private enterprises. Over 71 million files and 144 Tb of data were downloaded in 2015. As we endeavor to increase the quality and breadth of NLDAS products, a joint effort between NASA and NCEP is underway to enable the assimilation of hydrology-relevant remote sensing datasets within NLDAS through the NASA Land Information System (LIS). The use of LIS will also enable easier transition of newly upgraded land surface models into NCEP NLDAS operations. Cold season processes significantly affect water and energy cycles, and their partitioning. As such, in the evaluation of NLDAS systems it is important to assess water and energy exchanges and/or partitioning processes over high-elevations. The Rocky Mountain region of the western U. S. is chosen as such a region to analyze and compare snow water equivalent (SWE), snow cover, snow melt, snow sublimation, total runoff, and sensible heat and latent heat flux. Reference data sets (observation-based and reanalysis) of monthly SWE, streamflow, evapotranspiration, GRACE-based total water storage change, and energy fluxes are used to evaluate model-simulated results. The results show several key factors that affect model simulations: (1) forcing errors such as precipitation partitioning into snowfall and rainfall, (2) snow albedo, (3) refreezing of melted snow, (4) boundary layer stability, and (5) freezing and thawing of soil. Though the anomaly correlations indicate good agreement with the observations or reanalysis products, large quantitative differences are evident in certain cases.

Estimating Snow Water Equivalent over the American River in the Sierra Nevada Basin Using Wireless Sensor Networks

NASA Astrophysics Data System (ADS)

Welch, S. C.; Kerkez, B.; Glaser, S. D.; Bales, R. C.; Rice, R.

2011-12-01

We have designed a basin-scale (>2000 km2) instrument cluster, made up of 20 local-scale (1-km footprint) wireless sensor networks (WSNs), to measure patterns of snow depth and snow water equivalent (SWE) across the main snowmelt producing area within the American River basin. Each of the 20 WSNs has on the order of 25 wireless nodes, with over 10 nodes actively sensing snow depth, and thus snow accumulation and melt. When combined with existing snow density measurements and full-basin satellite snowcover data, these measurements are designed to provide dense ground-truth snow properties for research and real-time SWE for water management. The design of this large-scale network is based on rigorous testing of previous, smaller-scale studies, permitting for the development of methods to significantly, and efficiently scale up network operations. Recent advances in WSN technology have resulted in a modularized strategy that permits rapid future network deployment. To select network and sensor locations, various sensor placement approaches were compared, including random placement, placement of WSNs in locations that have captured the historical basin mean, as well as a placement algorithm leveraging the covariance structure of the SWE distribution. We show that that the optimal network locations do not exhibit a uniform grid, but rather follow strategic patterns based on physiographic terrain parameters. Uncertainty estimates are also provided to assess the confidence in the placement approach. To ensure near-optimal coverage of the full basin, we validated each placement approach with a multi-year record of SWE derived from reconstruction of historical satellite measurements.

An experimental study: quantitatively evaluating the change of the content of collagen fibres in penis with two-dimensional ShearWave™ Elastography.

PubMed

Qiao, X-H; Zhang, J-J; Gao, F; Li, F; Bai, M; Du, L-F; Xing, J-F

2017-06-01

The purpose of this study was to explore the value of two-dimensional ShearWave ™ Elastography (2D-SWE) on quantitatively evaluating the change of the content of collagen fibres in penis. Twenty male Sprague Dawley rats were divided into the pre-sexual maturity group (Group 1) and the sexual decline group (Group 2) according to age. The ultrafast ultrasound device Aixplorer ® (SuperSonic Imagine, Aix-en-Provence, France) was used for 2D-SWE imaging of penis, and the measurement index was shear wave stiffness (SWS). The immunohistochemistry was used to analyse the content of collagen fibres in penis, and the measurement index was positive area percentage (PAP). The differences of SWS between the two groups and PAP between the two groups were analysed. SWS of Group 1 and Group 2 was 10.18 ± 1.09 and 8.02 ± 1.34 kPa, and SWS of Group 2 was significantly lower than Group 1 (p < .01). PAP of Group 1 and Group 2 was 4.83 ± 3.61% and 16.41 ± 10.02%, and PAP of Group 2 was significantly higher than Group 1 (p < .01). Our results indicate that when the content of collagen fibres changes, SWS of penis measured with 2D-SWE would change significantly as well. Two-dimensional SWE can be used to quantitatively evaluate the change of the content of collagen fibres in penis. © 2016 Blackwell Verlag GmbH.

Well-Being and Diabetes Management in Early Pregnant Women with Type 1 Diabetes Mellitus.

PubMed

Linden, Karolina; Sparud-Lundin, Carina; Adolfsson, Annsofie; Berg, Marie

2016-08-22

This paper explores well-being and diabetes management in women with type 1 diabetes mellitus (DM) in early pregnancy and investigates associations among perceived well-being, diabetes management, and maternal characteristics. Questionnaires were answered by 168 Swedish women. Correlation analyses were conducted with Spearman's correlation coefficient (rs). The women reported relatively high scores of self-efficacy in diabetes management (SWE-DES-10: 3.91 (0.51)) and self-perceived health (excellent (6.5%), very good (42.3%), good (38.7%), fair (11.3%) and poor (1.2%)). Moderate scores were reported for general well-being (WBQ-12: 22.6 (5.7)) and sense of coherence (SOC-13: 68.9 (9.7), moderate/low scores for hypoglycemia fear (SWE-HFS 26.6 (11.8)) and low scores of diabetes-distress (SWE-PAID-20 27.1 (15.9)). A higher capability of self-efficacy in diabetes management showed positive correlations with self-perceived health (rs = -0.41, p < 0.0001) and well-being (rs = 0.34, p < 0.0001) as well as negative correlations with diabetes distress (rs = -0.51, p < 0.0001) and hypoglycemia worries (rs = -0.27, p = 0.0009). Women with HbA1c levels of ≤48 mmL/mol scored higher in the subscales "goal achievement" in SWE-DES (p = 0.0028) and "comprehensibility" in SOC (p = 0.016). Well-being and diabetes management could be supported by strengthening the women's capability to achieve glycemic goals and their comprehensibility in relation to the treatment. Further studies are needed to test this.

An elevational gradient in snowpack chemical loading at Glacier National Park, Montana: implications for ecosystem processes

USGS Publications Warehouse

Fagre, Daniel; Tonnessen, Kathy; Morris, Kristi; Ingersoll, George; McKeon, Lisa; Holzer, Karen

2000-01-01

The accumulation and melting of mountain snowpacks are major drivers of ecosystem processes in the Rocky Mountains. These include the influence of snow water equivalent (SWE) timing and amount of release on soil moisture for annual tree growth, and alpine stream discharge and temperature that control aquatic biota life histories. Snowfall also brings with it atmospheric deposition. Snowpacks will hold as much as 8 months of atmospheric deposition for release into mountain ecosystems during the spring melt. These pulses of chemicals influence soil microbiota and biogeochemical processes affecting mountain vegetation growth. Increased atmospheric nitrogen inputs recently have been documented in remote parts of Colorado's mountain systems but no baseline data exist for the Northern Rockies. We examined patterns of SWE and snow chemistry in an elevational gradient stretching from west to east over the continental divide in Glacier National Park in March 1999 and 2000. Sites ranged from 1080m to 2192m at Swiftcurrent Pass. At each site, two vertically-integrated columns of snow were sampled from snowpits up to 600cm deep and analyzed for major cations and anions. Minor differences in snow chemistry, on a volumetric basis, existed over the elvational gradient. Snowpack chemical loading estimates were calculated for NH4, SO4 and NO3 and closely followed elevational increases in SWE. NO3 (in microequivalents/square meter) ranged from 1,000 ueq/m2 at low elevation sites to 8,000+ ueq/m2 for high elevation sites. Western slopes received greater amounts of SWE and chemical loads for all tested compounds.

Conifer Growth Response to Snowpack across an Elevation Gradient in Northern Sierra Nevada Mountains, California

NASA Astrophysics Data System (ADS)

Lepley, K. S.; Touchan, R.; Meko, D. M.; Graham, R.; Shamir, E.

2016-12-01

The United States depends heavily on the agricultural resources of the state of California, and water is the key factor in sustaining these resources. Around a third of the state's water supply originates from snow in the Sierra Nevada Mountains. Managing this resource demands understanding of climatic variability on time-scales of decades to centuries to plan for drought conditions in the region. Tree-ring growth spanning several centuries can serve as proxy records and provide the knowledge upon which to base sound decisions for water-resource management. Here we will discuss the growth-response of six tree species to April 1st snow-water equivalent (SWE) across an elevation gradient of 1500 m to 2525 m. Higher elevation (ca. 1890 m to 2525 m) tree-ring chronologies exhibit significant correlation (r = 0.45 to r = 0.57, p < 0.01) with April 1st SWE during the 20th century. Abies magnifica (ABMA), Tsuga mertensiana, and Calocedrus decurrens exhibit a positive response to prior-year snowpack, while Abies concolor responds positively to same-year snowpack. Lower elevation Pinus ponderosa (PIPO) and Juniperus occidentalis chronologies show no significant correlation with SWE, however PIPO responds positively at a site 500 m higher in elevation. In contrast, ABMA chronologies from two sites with a 500 m elevation difference exhibit the same response to snowpack. The strong relationship between annual tree-ring growth and April 1st SWE in these tree species opens possibilities of exploring historic snowpack patterns and elucidating dendroclimatic relationships in the mountainous west.

An ontology for sensor networks

NASA Astrophysics Data System (ADS)

Compton, Michael; Neuhaus, Holger; Bermudez, Luis; Cox, Simon

2010-05-01

Sensors and networks of sensors are important ways of monitoring and digitizing reality. As the number and size of sensor networks grows, so too does the amount of data collected. Users of such networks typically need to discover the sensors and data that fit their needs without necessarily understanding the complexities of the network itself. The burden on users is eased if the network and its data are expressed in terms of concepts familiar to the users and their job functions, rather than in terms of the network or how it was designed. Furthermore, the task of collecting and combining data from multiple sensor networks is made easier if metadata about the data and the networks is stored in a format and conceptual models that is amenable to machine reasoning and inference. While the OGC's (Open Geospatial Consortium) SWE (Sensor Web Enablement) standards provide for the description and access to data and metadata for sensors, they do not provide facilities for abstraction, categorization, and reasoning consistent with standard technologies. Once sensors and networks are described using rich semantics (that is, by using logic to describe the sensors, the domain of interest, and the measurements) then reasoning and classification can be used to analyse and categorise data, relate measurements with similar information content, and manage, query and task sensors. This will enable types of automated processing and logical assurance built on OGC standards. The W3C SSN-XG (Semantic Sensor Networks Incubator Group) is producing a generic ontology to describe sensors, their environment and the measurements they make. The ontology provides definitions for the structure of sensors and observations, leaving the details of the observed domain unspecified. This allows abstract representations of real world entities, which are not observed directly but through their observable qualities. Domain semantics, units of measurement, time and time series, and location and mobility ontologies can be easily attached when instantiating the ontology for any particular sensors in a domain. After a review of previous work on the specification of sensors, the group is developing the ontology in conjunction with use case development. Part of the difficulty of such work is that relevant concepts from for example OGC standards and other ontologies must be identified and aligned and also placed in a consistent and logically correct way into the ontology. In terms of alignment with OGC's SWE, the ontology is intended to be able to model concepts from SensorML and O&M. Similar to SensorML and O&M, the ontology is based around concepts of systems, processes, and observations. It supports the description of the physical and processing structure of sensors. Sensors are not constrained to physical sensing devices: rather a sensor is anything that can estimate or calculate the value of a phenomenon, so a device or computational process or combination could play the role of a sensor. The representation of a sensor in the ontology links together what is measured (the domain phenomena), the sensor's physical and other properties and its functions and processing. Parts of the ontology are well aligned with SensorML and O&M, but parts are not, and the group is working to understand how differences from (and alignment with) the OGC standards affect the application of the ontology.

A Comprehensive Snow Density Model for Integrating Lidar-Derived Snow Depth Data into Spatial Snow Modeling

NASA Astrophysics Data System (ADS)

Marks, D. G.; Kormos, P.; Johnson, M.; Bormann, K. J.; Hedrick, A. R.; Havens, S.; Robertson, M.; Painter, T. H.

2017-12-01

Lidar-derived snow depths when combined with modeled or estimated snow density can provide reliable estimates of the distribution of SWE over large mountain areas. Application of this approach is transforming western snow hydrology. We present a comprehensive approach toward modeling bulk snow density that is reliable over a vast range of weather and snow conditions. The method is applied and evaluated over mountainous regions of California, Idaho, Oregon and Colorado in the western US. Simulated and measured snow density are compared at fourteen validation sites across the western US where measurements of snow mass (SWE) and depth are co-located. Fitting statistics for ten sites from three mountain catchments (two in Idaho, one in California) show an average Nash-Sutcliff model efficiency coefficient of 0.83, and mean bias of 4 kg m-3. Results illustrate issues associated with monitoring snow depth and SWE and show the effectiveness of the model, with a small mean bias across a range of snow and climate conditions in the west.

Neural potentials disorder during differential psychoacoustic experiment evaluated by discrete wavelet analysis.

PubMed

Tsakiraki, Eleni S; Tsiaparas, Nikolaos N; Christopoulou, Maria I; Papageorgiou, Charalabos Ch; Nikita, Konstantina S

2014-01-01

The aim of the paper is the assessment of neural potentials disorder during a differential sensitivity psychoacoustic procedure. Ten volunteers were asked to compare the duration of two acoustic pulses: one reference with stable duration of 500 ms and one trial which varied from 420 ms to 620 ms. During the discrimination task, Electroencephalogram (EEG) and Event Related Potential (ERP) signals were recorded. The mean Relative Wavelet Energy (mRWE) and the normalized Shannon Wavelet Entropy (nSWE) are computed based on the Discrete Wavelet analysis. The results are correlated to the data derived by the psychoacoustic analysis on the volunteers responses. In most of the electrodes, when the duration of the trial pulse is 460 ms and 560 ms, there is an increase and a decrease in nSWE value, respectively, which is determined mostly by the mRWE in delta rhythm. These extrema are correlated to the Just Noticeable Difference (JND) in pulses duration, calculated by psychoacoustic analysis. The dominance of delta rhythm during the whole auditory experiment is noteworthy. The lowest values of nSWE are noted in temporal lobe.

Modeling snow accumulation and ablation processes in forested environments

NASA Astrophysics Data System (ADS)

Andreadis, Konstantinos M.; Storck, Pascal; Lettenmaier, Dennis P.

2009-05-01

The effects of forest canopies on snow accumulation and ablation processes can be very important for the hydrology of midlatitude and high-latitude areas. A mass and energy balance model for snow accumulation and ablation processes in forested environments was developed utilizing extensive measurements of snow interception and release in a maritime mountainous site in Oregon. The model was evaluated using 2 years of weighing lysimeter data and was able to reproduce the snow water equivalent (SWE) evolution throughout winters both beneath the canopy and in the nearby clearing, with correlations to observations ranging from 0.81 to 0.99. Additionally, the model was evaluated using measurements from a Boreal Ecosystem-Atmosphere Study (BOREAS) field site in Canada to test the robustness of the canopy snow interception algorithm in a much different climate. Simulated SWE was relatively close to the observations for the forested sites, with discrepancies evident in some cases. Although the model formulation appeared robust for both types of climates, sensitivity to parameters such as snow roughness length and maximum interception capacity suggested the magnitude of improvements of SWE simulations that might be achieved by calibration.

MO and DA on the SWIE Instrument on the Wind Spacecraft

NASA Technical Reports Server (NTRS)

Lazarus, Alan J.

2002-01-01

The construction of the Faraday Cup portion of the SWIE instrument on the Wind spacecraft, participation in Mission Operations, and Data Analysis (MO and DA) of observations of the solar wind has been supported by a sequence of grants. This 'final' Report represents work done on Mission Operations and Data Analysis for the Faraday Cup portion of the SWE. The work reported here was supported under NASA Grant NAG5-7359 (OSP 6701100) from June 1998 to October 2001. It should be noted that this work is continuing under NASA Grant NAG-10915, and therefore this report is 'final' only in the sense that the Grant has changed its number; a future report will cover the entire period of work. We have two types of obligations under these contracts: (1) To provide and assure the validity of "Key Parameters" which describe the basic properties of the solar wind on a daily basis. We have provided our 92 second observations daily via plots and parameters available from our Web site: http://web.mit.edu/space/www/wind/wind.html (2). To carry out scientific studies based on our observations. To document the extent of our research, we are including below a list of publications and presentations related to this project. The observations from Wind have made a major contribution to the study of the solar wind, and have every indication of continuing to do so.

Using a Web GIS Plate Tectonics Simulation to Promote Geospatial Thinking

ERIC Educational Resources Information Center

Bodzin, Alec M.; Anastasio, David; Sharif, Rajhida; Rutzmoser, Scott

2016-01-01

Learning with Web-based geographic information system (Web GIS) can promote geospatial thinking and analysis of georeferenced data. Web GIS can enable learners to analyze rich data sets to understand spatial relationships that are managed in georeferenced data visualizations. We developed a Web GIS plate tectonics simulation as a capstone learning…

Using the Geospatial Web to Deliver and Teach Giscience Education Programs

NASA Astrophysics Data System (ADS)

Veenendaal, B.

2015-05-01

Geographic information science (GIScience) education has undergone enormous changes over the past years. One major factor influencing this change is the role of the geospatial web in GIScience. In addition to the use of the web for enabling and enhancing GIScience education, it is also used as the infrastructure for communicating and collaborating among geospatial data and users. The web becomes both the means and the content for a geospatial education program. However, the web does not replace the traditional face-to-face environment, but rather is a means to enhance it, expand it and enable an authentic and real world learning environment. This paper outlines the use of the web in both the delivery and content of the GIScience program at Curtin University. The teaching of the geospatial web, web and cloud based mapping, and geospatial web services are key components of the program, and the use of the web and online learning are important to deliver this program. Some examples of authentic and real world learning environments are provided including joint learning activities with partner universities.

A New User Interface for On-Demand Customizable Data Products for Sensors in a SensorWeb

NASA Technical Reports Server (NTRS)

Mandl, Daniel; Cappelaere, Pat; Frye, Stuart; Sohlberg, Rob; Ly, Vuong; Chien, Steve; Sullivan, Don

2011-01-01

A SensorWeb is a set of sensors, which can consist of ground, airborne and space-based sensors interoperating in an automated or autonomous collaborative manner. The NASA SensorWeb toolbox, developed at NASA/GSFC in collaboration with NASA/JPL, NASA/Ames and other partners, is a set of software and standards that (1) enables users to create virtual private networks of sensors over open networks; (2) provides the capability to orchestrate their actions; (3) provides the capability to customize the output data products and (4) enables automated delivery of the data products to the users desktop. A recent addition to the SensorWeb Toolbox is a new user interface, together with web services co-resident with the sensors, to enable rapid creation, loading and execution of new algorithms for processing sensor data. The web service along with the user interface follows the Open Geospatial Consortium (OGC) standard called Web Coverage Processing Service (WCPS). This presentation will detail the prototype that was built and how the WCPS was tested against a HyspIRI flight testbed and an elastic computation cloud on the ground with EO-1 data. HyspIRI is a future NASA decadal mission. The elastic computation cloud stores EO-1 data and runs software similar to Amazon online shopping.

On Representative Spaceflight Instrument and Associated Instrument Sensor Web Framework

NASA Technical Reports Server (NTRS)

Kizhner, Semion; Patel, Umeshkumar; Vootukuru, Meg

2007-01-01

Sensor Web-based adaptation and sharing of space flight mission resources, including those of the Space-Ground and Control-User communication segment, could greatly benefit from utilization of heritage Internet Protocols and devices applied for Spaceflight (SpaceIP). This had been successfully demonstrated by a few recent spaceflight experiments. However, while terrestrial applications of Internet protocols are well developed and understood (mostly due to billions of dollars in investments by the military and industry), the spaceflight application of Internet protocols is still in its infancy. Progress in the developments of SpaceIP-enabled instrument components will largely determine the SpaceIP utilization of those investments and acceptance in years to come. Likewise SpaceIP, the development of commercial real-time and instrument colocated computational resources, data compression and storage, can be enabled on-board a spacecraft and, in turn, support a powerful application to Sensor Web-based design of a spaceflight instrument. Sensor Web-enabled reconfiguration and adaptation of structures for hardware resources and information systems will commence application of Field Programmable Arrays (FPGA) and other aerospace programmable logic devices for what this technology was intended. These are a few obvious potential benefits of Sensor Web technologies for spaceflight applications. However, they are still waiting to be explored. This is because there is a need for a new approach to spaceflight instrumentation in order to make these mature sensor web technologies applicable for spaceflight. In this paper we present an approach in developing related and enabling spaceflight instrument-level technologies based on the new concept of a representative spaceflight Instrument Sensor Web (ISW).

Reductive dechlorination of polychlorinated biphenyls by zerovalent iron in subcritical water

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yak, H.K.; Wenclawiak, B.W.; Cheng, I.F.

1999-04-15

A method for remediation of PCB-contaminated soil and sediments is described that uses zerovalent iron as the dechlorination agent and subcritical water extraction (SWE) as the transporting medium. By using 100-mesh iron powder and SWE conditions of 250 C and 10 MPa on Aroclor 1260 for 1--8 h, the higher chlorine-substituted homologues were completely reduced to their lower substituted counterparts. The lower-substituted congeners were subsequently near-completely dechlorinated. The initial findings indicate that this technique may be a viable method for remediation of PCB-contaminated soil and sediments.

WIND measurements of proton and alpha particle flow and number density

NASA Technical Reports Server (NTRS)

Steinberg, J. T.; Lazarus, A. J.; Ogilvie, J. T.; Lepping, R.; Byrnes, J.; Chornay, D.; Keller, J.; Torbert, R. B.; Bodet, D.; Needell, G. J.

1995-01-01

We propose to review measurements of the solar wind proton and alpha particle flow velocities and densities made since launch with the WIND SWE instrument. The SWE Faraday cup ion sensors are designed to be able to determine accurately flow vector directions, and thus can be used to detect proton-alpha particle differential flow. Instances of differential flow, and the solar wind features with which they are associated will be discussed. Additionally, the variability of the percentage of alpha particles as a fraction of the total solar wind ion density will be presented.

CerebralWeb: a Cytoscape.js plug-in to visualize networks stratified by subcellular localization.

PubMed

Frias, Silvia; Bryan, Kenneth; Brinkman, Fiona S L; Lynn, David J

2015-01-01

CerebralWeb is a light-weight JavaScript plug-in that extends Cytoscape.js to enable fast and interactive visualization of molecular interaction networks stratified based on subcellular localization or other user-supplied annotation. The application is designed to be easily integrated into any website and is configurable to support customized network visualization. CerebralWeb also supports the automatic retrieval of Cerebral-compatible localizations for human, mouse and bovine genes via a web service and enables the automated parsing of Cytoscape compatible XGMML network files. CerebralWeb currently supports embedded network visualization on the InnateDB (www.innatedb.com) and Allergy and Asthma Portal (allergen.innatedb.com) database and analysis resources. Database tool URL: http://www.innatedb.com/CerebralWeb © The Author(s) 2015. Published by Oxford University Press.

Simulations of a Canadian snowpack brightness temperatures using SURFEX-Crocus for Snow Water Equivalent (SWE) retrievals

NASA Astrophysics Data System (ADS)

Larue, Fanny; Royer, Alain; De Sève, Danielle; Langlois, Alexandre; Roy, Alexandre; Saint-Jean-Rondeau, Olivier

2016-04-01

In Quebec, the water associated to snowmelt represents 30% of the annual electricity production so that the snow cover evaluation in real time is of primary interest. The key variable is snow water equivalent (SWE) which describes the evolution of a global seasonal snow cover. However, the sparse distribution of meteorological stations in northern Québec generates great uncertainty in the extrapolation of SWE. On the contrary, the spatial and temporal coverage of satellite data offer a source of information with a high potential when considered as an alternative to the poor spatial distribution of in-situ information. Thus, this project aims to improve the prediction of SWE by assimilation of satellite passive microwave brightness temperatures (Tb) observations, independently of any ground observations. The snowpack evolution is simulated by the French snow model SURFEX-Crocus, driven by the Canadian atmospheric model GEM with a spatial resolution of 10 km. The bias of the atmospheric model and the impact of initialization errors on the simulated SWE were quantified from our ground measurements. To assimilate satellite observations, the multi-layered snow model is first coupled with a radiative transfer model using the Dense Media Radiative transfer theory (the DMRT-ML model) to estimate the microwave snow emission of the simulated snowpack. In order to retrieve simulated Tb in frequencies of interest (i.e. sensitive to snow dielectric properties), the snow microstructure needs to be well parameterized. It was shown in previous studies that the specific surface area (SSA) of snow grains is a well-defined parameter to describe the size and the shape of snow grains and which allows reproducible field measurements. SURFEX-Crocus estimates a SSA for each simulated snow layer, however, the snow microstructure in DMRT-ML is defined per layer by monodisperse optical radius of grain (~ 1/SSA) and by the stickiness which is not known. It thus becomes necessary to introduce an empirical factor (noted φ) due to the simplification of the representation of snow as non-sticky spheres of ice in the model. In other words, the measured and simulated SSA has to be converted in an effective snow grain metric by optimizing this scaling factor to minimize the root-mean-square error between the measured and simulated brightness temperatures. The φ factor scaling the Crocus simulated SSA was estimated using ground-based radiometric measurements made during several field campaigns in the James Bay territory, Nunavik (in 2013 and 2015), and Churchill, Manitoba in 2010. This new parameterization, adapted to the Canadian arctic and subarctic snowpack, represents an essential step to optimize SWE maps in this remote region which have yet to be proven accurate.

Influence of subject presentation on interpretation of body composition change after 6 months of self-selected training and diet in athletic males.

PubMed

Kerr, Ava D; Slater, Gary J; Byrne, Nuala M

2018-06-01

High precision body composition assessment methods accurately monitor physique traits in athletes. The acute impact of subject presentation (ad libitum food and fluid intake plus physical activity) on body composition estimation using field and laboratory methods has been quantified, but the impact on interpretation of longitudinal change is unknown. This study evaluated the impact of athlete presentation (standardised versus non-standardised) on interpretation of change in physique traits over time. Thirty athletic males (31.2 ± 7.5 years; 182.2 ± 6.5 cm; 91.7 ± 10.3 kg; 27.6 ± 2.6 kg/m 2 ) underwent two testing sessions on 1 day including surface anthropometry, dual-energy X-ray absorptiometry (DXA), bioelectrical impedance spectroscopy (BIS) and air displacement plethysmography (via the BOD POD), with combinations of these used to establish three-compartment (3C) and four-compartment (4C) models. Tests were conducted after an overnight fast (BASEam) and ~ 7 h later after ad libitum food/fluid and physical activity (BASEpm). This procedure was repeated 6 months later (POSTam and POSTpm). Magnitude of changes in the mean was assessed by standardisation. After 6 months of self-selected training and diet, standardised presentation testing (BASEam to POSTam) identified trivial changes from the smallest worthwhile effect (SWE) in fat-free mass (FFM) and fat mass (FM) for all methods except for BIS (FM) where there was a large change (7.2%) from the SWE. Non-standardised follow-up testing (BASEam to POSTpm) showed trivial changes from the SWE except for small changes in FFM (BOD POD) of 1.1%, and in FM (3C and 4C models) of 6.4 and 3.5%. Large changes from the SWE were found in FFM (BIS, 3C and 4C models) of 2.2, 1.8 and 1.8% and in FM (BIS) of 6.4%. Non-standardised presentation testing (BASEpm to POSTpm) identified trivial changes from the SWE in FFM except for BIS which was small (1.1%). A moderate change from the SWE was found for BOD POD (3.3%) and large for BIS (9.4%) in FM estimations. Changes in body composition utilising non-standardised presentation were more substantial and often in the opposite direction to those identified using standardised presentation, causing misinterpretation of change in physique traits. Standardised presentation prior to body composition assessment for athletic populations should be advocated to enhance interpretation of true change.

Framework for Building Collaborative Research Environment

DOE PAGES

Devarakonda, Ranjeet; Palanisamy, Giriprakash; San Gil, Inigo

2014-10-25

Wide range of expertise and technologies are the key to solving some global problems. Semantic web technology can revolutionize the nature of how scientific knowledge is produced and shared. The semantic web is all about enabling machine-machine readability instead of a routine human-human interaction. Carefully structured data, as in machine readable data is the key to enabling these interactions. Drupal is an example of one such toolset that can render all the functionalities of Semantic Web technology right out of the box. Drupal’s content management system automatically stores the data in a structured format enabling it to be machine. Withinmore » this paper, we will discuss how Drupal promotes collaboration in a research setting such as Oak Ridge National Laboratory (ORNL) and Long Term Ecological Research Center (LTER) and how it is effectively using the Semantic Web in achieving this.« less

QTIMaps: A Model to Enable Web Maps in Assessment

ERIC Educational Resources Information Center

Navarrete, Toni; Santos, Patricia; Hernandez-Leo, Davinia; Blat, Josep

2011-01-01

Test-based e-Assessment approaches are mostly focused on the assessment of knowledge and not on that of other skills, which could be supported by multimedia interactive services. This paper presents the QTIMaps model, which combines the IMS QTI standard with web maps services enabling the computational assessment of geographical skills. We…

Developing Guidelines for Evaluating the Adaptation of Accessible Web-Based Learning Materials

ERIC Educational Resources Information Center

Radovan, Marko; Perdih, Mojca

2016-01-01

E-learning is a rapidly developing form of education. One of the key characteristics of e-learning is flexibility, which enables easier access to knowledge for everyone. Information and communications technology (ICT), which is e-learning's main component, enables alternative means of accessing the web-based learning materials that comprise the…

Semantic web for integrated network analysis in biomedicine.

PubMed

Chen, Huajun; Ding, Li; Wu, Zhaohui; Yu, Tong; Dhanapalan, Lavanya; Chen, Jake Y

2009-03-01

The Semantic Web technology enables integration of heterogeneous data on the World Wide Web by making the semantics of data explicit through formal ontologies. In this article, we survey the feasibility and state of the art of utilizing the Semantic Web technology to represent, integrate and analyze the knowledge in various biomedical networks. We introduce a new conceptual framework, semantic graph mining, to enable researchers to integrate graph mining with ontology reasoning in network data analysis. Through four case studies, we demonstrate how semantic graph mining can be applied to the analysis of disease-causal genes, Gene Ontology category cross-talks, drug efficacy analysis and herb-drug interactions analysis.

A Citizen Science Campaign to Validate Snow Remote-Sensing Products

NASA Astrophysics Data System (ADS)

Wikstrom Jones, K.; Wolken, G. J.; Arendt, A. A.; Hill, D. F.; Crumley, R. L.; Setiawan, L.; Markle, B.

2017-12-01

The ability to quantify seasonal water retention and storage in mountain snow packs has implications for an array of important topics, including ecosystem function, water resources, hazard mitigation, validation of remote sensing products, climate modeling, and the economy. Runoff simulation models, which typically rely on gridded climate data and snow remote sensing products, would be greatly improved if uncertainties in estimates of snow depth distribution in high-elevation complex terrain could be reduced. This requires an increase in the spatial and temporal coverage of observational snow data in high-elevation data-poor regions. To this end, we launched Community Snow Observations (CSO). Participating citizen scientists use Mountain Hub, a multi-platform mobile and web-based crowdsourcing application that allows users to record, submit, and instantly share geo-located snow depth, snow water equivalence (SWE) measurements, measurement location photos, and snow grain information with project scientists and other citizen scientists. The snow observations are used to validate remote sensing products and modeled snow depth distribution. The project's prototype phase focused on Thompson Pass in south-central Alaska, an important infrastructure corridor that includes avalanche terrain and the Lowe River drainage and is essential to the City of Valdez and the fisheries of Prince William Sound. This year's efforts included website development, expansion of the Mountain Hub tool, and recruitment of citizen scientists through a combination of social media outreach, community presentations, and targeted recruitment of local avalanche professionals. We also conducted two intensive field data collection campaigns that coincided with an aerial photogrammetric survey. With more than 400 snow depth observations, we have generated a new snow remote-sensing product that better matches actual SWE quantities for Thompson Pass. In the next phase of the citizen science portion of this project we will focus on expanding our group of participants to a larger geographic area in Alaska, further develop our partnership with Mountain Hub, and build relationships in new communities as we conduct a photogrammetric survey in a different region next year.

The Web Resource Collaboration Center

ERIC Educational Resources Information Center

Dunlap, Joanna C.

2004-01-01

The Web Resource Collaboration Center (WRCC) is a web-based tool developed to help software engineers build their own web-based learning and performance support systems. Designed using various online communication and collaboration technologies, the WRCC enables people to: (1) build a learning and professional development resource that provides…

Autonomy and Sensor Webs: The Evolution of Mission Operations

NASA Technical Reports Server (NTRS)

Sherwood, Rob

2008-01-01

Demonstration of these sensor web capabilities will enable fast responding science campaigns that combine spaceborne, airborne, and ground assets. Sensor webs will also require new operations paradigms. These sensor webs will be operated directly by scientists using science goals to control their instruments. We will explore these new operations architectures through a study of existing sensor web prototypes.

EPA Web Taxonomy

EPA Pesticide Factsheets

EPA's Web Taxonomy is a faceted hierarchical vocabulary used to tag web pages with terms from a controlled vocabulary. Tagging enables search and discovery of EPA's Web based information assests. EPA's Web Taxonomy is being provided in Simple Knowledge Organization System (SKOS) format. SKOS is a standard for sharing and linking knowledge organization systems that promises to make Federal terminology resources more interoperable.

Cardiac shear-wave elastography using a transesophageal transducer: application to the mapping of thermal lesions in ultrasound transesophageal cardiac ablation

NASA Astrophysics Data System (ADS)

Kwiecinski, Wojciech; Bessière, Francis; Constanciel Colas, Elodie; Apoutou N'Djin, W.; Tanter, Mickaël; Lafon, Cyril; Pernot, Mathieu

2015-10-01

Heart rhythm disorders, such as atrial fibrillation or ventricular tachycardia can be treated by catheter-based thermal ablation. However, clinically available systems based on radio-frequency or cryothermal ablation suffer from limited energy penetration and the lack of lesion’s extent monitoring. An ultrasound-guided transesophageal device has recently successfully been used to perform High-Intensity Focused Ultrasound (HIFU) ablation in targeted regions of the heart in vivo. In this study we investigate the feasibility of a dual therapy and imaging approach on the same transesophageal device. We demonstrate in vivo that quantitative cardiac shear-wave elastography (SWE) can be performed with the device and we show on ex vivo samples that transesophageal SWE can map the extent of the HIFU lesions. First, SWE was validated with the transesophageal endoscope in one sheep in vivo. The stiffness of normal atrial and ventricular tissues has been assessed during the cardiac cycle (n=11 ) and mapped (n= 7 ). Second, HIFU ablation has been performed with the therapy-imaging transesophageal device in ex vivo chicken breast samples (n  =  3), then atrial (left, n= 2 ) and ventricular (left n=1 , right n=1 ) porcine heart tissues. SWE provided stiffness maps of the tissues before and after ablation. Areas of the lesions were obtained by tissue color change with gross pathology and compared to SWE. During the cardiac cycle stiffness varied from 0.5   ±   0.1 kPa to 6.0   ±   0.3 kPa in the atrium and from 1.3   ±   0.3 kPa to 13.5   ±   9.1 kPa in the ventricles. The thermal lesions were visible on all SWE maps performed after ablation. Shear modulus of the ablated zones increased to 16.3   ±   5.5 kPa (versus 4.4   ±   1.6 kPa before ablation) in the chicken breast, to 30.3   ±   10.3 kPa (versus 12.2   ±   4.3 kPa) in the atria and to 73.8   ±   13.9 kPa (versus 21.2   ±   3.3 kPa) in the ventricles. On gross pathology, the size of the lesions ranged from 0.1 to 1.5 cm2 in the imaging plane area. Elasticity-estimated depths and widths of the lesions differed respectively with a median of 0.2 mm (first quartile Q1:  -0.8 mm third quartile Q3: 2.6 mm) for a mean squared error (MSE) of 5.1 mm2 and a median of 0.2 mm (Q1:  -2.7 mm Q3: 2.7 mm) for a MSE of 11.1 mm2 from gross pathology. We have demonstrated the feasibility of the HIFU thermal ablation monitoring using a dual therapy and imaging transesophageal device. The combination of HIFU, ultrasound imaging and SWE on the same transesophageal system could lead to a new clinical device for a safer and controlled treatment of a wide variety of cardiac arrhythmias.

Cardiac shear-wave elastography using a transesophageal transducer: application to the mapping of thermal lesions in ultrasound transesophageal cardiac ablation.

PubMed

Kwiecinski, Wojciech; Bessière, Francis; Colas, Elodie Constanciel; N'Djin, W Apoutou; Tanter, Mickaël; Lafon, Cyril; Pernot, Mathieu

2015-10-21

Heart rhythm disorders, such as atrial fibrillation or ventricular tachycardia can be treated by catheter-based thermal ablation. However, clinically available systems based on radio-frequency or cryothermal ablation suffer from limited energy penetration and the lack of lesion's extent monitoring. An ultrasound-guided transesophageal device has recently successfully been used to perform High-Intensity Focused Ultrasound (HIFU) ablation in targeted regions of the heart in vivo. In this study we investigate the feasibility of a dual therapy and imaging approach on the same transesophageal device. We demonstrate in vivo that quantitative cardiac shear-wave elastography (SWE) can be performed with the device and we show on ex vivo samples that transesophageal SWE can map the extent of the HIFU lesions. First, SWE was validated with the transesophageal endoscope in one sheep in vivo. The stiffness of normal atrial and ventricular tissues has been assessed during the cardiac cycle (n = 11) and mapped (n = 7). Second, HIFU ablation has been performed with the therapy-imaging transesophageal device in ex vivo chicken breast samples (n  =  3), then atrial (left, n = 2) and ventricular (left n = 1, right n = 1) porcine heart tissues. SWE provided stiffness maps of the tissues before and after ablation. Areas of the lesions were obtained by tissue color change with gross pathology and compared to SWE. During the cardiac cycle stiffness varied from 0.5   ±   0.1 kPa to 6.0   ±   0.3 kPa in the atrium and from 1.3   ±   0.3 kPa to 13.5   ±   9.1 kPa in the ventricles. The thermal lesions were visible on all SWE maps performed after ablation. Shear modulus of the ablated zones increased to 16.3   ±   5.5 kPa (versus 4.4   ±   1.6 kPa before ablation) in the chicken breast, to 30.3   ±   10.3 kPa (versus 12.2   ±   4.3 kPa) in the atria and to 73.8   ±   13.9 kPa (versus 21.2   ±   3.3 kPa) in the ventricles. On gross pathology, the size of the lesions ranged from 0.1 to 1.5 cm(2) in the imaging plane area. Elasticity-estimated depths and widths of the lesions differed respectively with a median of 0.2 mm (first quartile Q1:  -0.8 mm; third quartile Q3: 2.6 mm) for a mean squared error (MSE) of 5.1 mm(2) and a median of 0.2 mm (Q1:  -2.7 mm; Q3: 2.7 mm) for a MSE of 11.1 mm(2) from gross pathology. We have demonstrated the feasibility of the HIFU thermal ablation monitoring using a dual therapy and imaging transesophageal device. The combination of HIFU, ultrasound imaging and SWE on the same transesophageal system could lead to a new clinical device for a safer and controlled treatment of a wide variety of cardiac arrhythmias.

How Does Snow Persistence Relate to Annual Streamflow in Mountain Watersheds of the Western U.S. With Wet Maritime and Dry Continental Climates?

NASA Astrophysics Data System (ADS)

Hammond, John C.; Saavedra, Freddy A.; Kampf, Stephanie K.

2018-04-01

With climate warming, many regions are experiencing changes in snow accumulation and persistence. These changes are known to affect streamflow volume, but the magnitude of the effect varies between regions. This research evaluates whether variables derived from remotely sensed snow cover can be used to estimate annual streamflow at the small watershed scale across the western U.S., a region with a wide range of climate types. We compared snow cover variables derived from MODIS, snow persistence (SP), and snow season (SS), to more commonly utilized metrics, snow fraction (fraction of precipitation falling as snow, SF), and peak snow water equivalent (SWE). Each variable represents different information about snow, and this comparison assesses similarities and differences between the snow metrics. Next, we evaluated how two snow variables, SP and SWE, related to annual streamflow (Q) for 119 USGS reference watersheds and examined whether these relationships varied for wet/warm (precipitation surplus) and dry/cold (precipitation deficit) watersheds. Results showed high correlations between all snow variables, but the slopes of these relationships differed between climates, with wet/warm watersheds displaying lower SF and higher SWE for the same SP. In dry/cold watersheds, both SP and SNODAS SWE correlated with Q spatially across all watersheds and over time within individual watersheds. We conclude that SP can be used to map spatial patterns of annual streamflow generation in dry/cold parts of the region. Applying this approach to the Upper Colorado River Basin demonstrates that 50% of streamflow comes from areas >3,000 masl. If the relationship between SP and Q is similar in other dry/cold regions, this approach could be used to estimate annual streamflow in ungauged basins.

Effect of Different Tree canopies on the Brightness Temperature of Snowpack

NASA Astrophysics Data System (ADS)

Mousavi, S.; De Roo, R. D.; Brucker, L.

2017-12-01

Snow stores the water we drink and is essential to grow food that we eat. But changes in snow quantities such as snow water equivalent (SWE) are underway and have serious consequences. So, effective management of the freshwater reservoir requires to monitor frequently (weekly or better) the spatial distribution of SWE and snowpack wetness. Both microwave radar and radiometer systems have long been considered as relevant remote sensing tools in retrieving globally snow physical parameters of interest thanks to their all-weather operation capability. However, their observations are sensitive to the presence of tree canopies, which in turns impacts SWE estimation. To address this long-lasting challenge, we parked a truck-mounted microwave radiometer system for an entire winter in a rare area where it exists different tree types in the different cardinal directions. We used dual-polarization microwave radiometers at three different frequencies (1.4, 19, and 37 GHz), mounted on a boom truck to observe continuously the snowpack surrounding the truck. Observations were recorded at different incidence angles. These measurements have been collected in Grand Mesa National Forest, Colorado as part of the NASA SnowEx 2016-17. In this presentation, the effect of Engelmann Spruce and Aspen trees on the measured brightness temperature of snow is discussed. It is shown that Engelmann Spruce trees increases the brightness temperature of the snowpack more than Aspen trees do. Moreover, the elevation angular dependence of the measured brightness temperatures of snowpack with and without tree canopies is investigated in the context of SWE retrievals. A time-lapse camera was monitoring a snow post installed in the sensors' field of view to characterize the brightness temperature change as snow depth evolved. Also, our study takes advantage of the snowpit measurements that were collected near the radiometers' field of view.

Observation of the standing wave effect in large-area, very-high-frequency capacitively coupled plasmas by using a fiber Bragg grating sensor

NASA Astrophysics Data System (ADS)

Han, Dao-Man; Liu, Yong-Xin; Gao, Fei; Wang, Xiang-Yu; Li, Ang; Xu, Jun; Jing, Zhen-Guo; Wang, You-Nian

2018-06-01

The large-area capacitive discharges driven at very high frequencies have been attracting much attention due to their wide applications in material etching and thin film deposition. However, in the regime, the standing wave effect (SWE) becomes a major limitation for plasma material processing uniformity. In this work, a fiber Bragg grating sensor was utilized for the observation of the SWE in a large-area capacitive discharge reactor by measuring the radial distribution of the neutral gas temperature T g. The influences of the RF power and the working pressure on the radial profiles of T g were studied. At a higher frequency (100 MHz) and a lower pressure (5 Pa), T g presents a center-peaked radial distribution, indicating a significant SWE. As the RF power increases, the central peak of T g becomes more evident due to the enhanced SWE. By contrast, at 100 MHz and a higher pressure (40 Pa), the radial distribution of T g shows an evident peak at the electrode edge and T g decays dramatically towards the discharge center because the electromagnetic waves are strongly damped as they are propagating from the edge to the center. At a lower frequency (27 MHz), only edge-high profiles of T g are observed for various pressures. For the sake of a comparison, a hairpin resonance probe was used to measure the radial distributions of the plasma density n p under the same condition. The radial profiles of T g are found to generally resemble those of n p under various conditions. Based on the experimental results, the neutral gas heating mechanism was analyzed.

SWEAT: Snow Water Equivalent with AlTimetry

NASA Astrophysics Data System (ADS)

Agten, Dries; Benninga, Harm-Jan; Diaz Schümmer, Carlos; Donnerer, Julia; Fischer, Georg; Henriksen, Marie; Hippert Ferrer, Alexandre; Jamali, Maryam; Marinaci, Stefano; Mould, Toby JD; Phelan, Liam; Rosker, Stephanie; Schrenker, Caroline; Schulze, Kerstin; Emanuel Telo Bordalo Monteiro, Jorge

2017-04-01

To study how the water cycle changes over time, satellite and airborne remote sensing missions are typically employed. Over the last 40 years of satellite missions, the measurement of true water inventories stored in sea and land ice within the cryosphere have been significantly hindered by uncertainties introduced by snow cover. Being able to determine the thickness of this snow cover would act to reduce such error, improving current estimations of hydrological and climate models, Earth's energy balance (albedo) calculations and flood predictions. Therefore, the target of the SWEAT (Snow Water Equivalent with AlTimetry) mission is to directly measure the surface Snow Water Equivalent (SWE) on sea and land ice within the polar regions above 60°and below -60° latitude. There are no other satellite missions currently capable of directly measuring SWE. In order to achieve this, the proposed mission will implement a novel combination of Ka- and Ku-band radioaltimeters (active microwave sensors), capable of penetrating into the snow microstructure. The Ka-band altimeter (λ ≈ 0.8 cm) provides a low maximum snow pack penetration depth of up to 20 cm for dry snow at 37 GHz, since the volume scattering of snow dominates over the scattering caused by the underlying ice surface. In contrast, the Ku-band altimeter (λ ≈ 2 cm) provides a high maximum snowpack penetration depth of up to 15 m in high latitudes regions with dry snow, as volume scattering is decreased by a factor of 55. The combined difference in Ka- and Ku-band signal penetration results will provide more accurate and direct determination of SWE. Therefore, the SWEAT mission aims to improve estimations of global SWE interpreted from passive microwave products, and improve the reliability of numerical snow and climate models.

Risk of falling in a stroke unit after acute stroke: The Fall Study of Gothenburg (FallsGOT).

PubMed

Persson, Carina U; Kjellberg, Sigvar; Lernfelt, Bodil; Westerlind, Ellen; Cruce, Malin; Hansson, Per-Olof

2018-03-01

This study aimed to investigate incidence of falls and different baseline variables and their association with falling during hospitalization in a stroke unit among patients with acute stroke. Prospective observational study. A stroke unit at a university hospital. A consecutive sample of stroke patients, out of which 504 were included, while 101 declined participation. The patients were assessed a mean of 1.7 days after admission and 3.8 days after stroke onset. The primary end-point was any fall, from admission to the stroke unit to discharge. Factors associated with falling were analysed using univariable and multivariable Cox hazard regression analyses. Independent variables were related to function, activity and participation, as well as personal and environmental factors. In total, 65 patients (13%) fell at least once. Factors statistically significantly associated with falling in the multivariable analysis were male sex (hazard ratio (HR): 1.88, 95% confidence interval (CI): 1.13-3.14, P = 0.015), use of a walking aid (HR: 2.11, 95% CI: 1.24-3.60, P = 0.006) and postural control as assessed with the modified version of the Postural Assessment Scale for Stroke Patients (SwePASS). No association was found with age, cognition or stroke severity, the HR for low SwePASS scores (⩽24) was 9.33 (95% CI: 2.19-39.78, P = 0.003) and for medium SwePASS scores (25-30) was 6.34 (95% CI: 1.46-27.51, P = 0.014), compared with high SwePASS scores (⩾31). Postural control, male sex and use of a walking aid are associated with falling during hospitalization after acute stroke.

Determination of the Elasticity of Breast Tissue during the Menstrual Cycle Using Real-Time Shear Wave Elastography.

PubMed

Li, Xiang; Wang, Jian-Nan; Fan, Zhi-Ying; Kang, Shu; Liu, Yan-Jun; Zhang, Yi-Xia; Wang, Xue-Mei

2015-12-01

We examined breast tissue elasticity during the menstrual cycle using real-time shear wave elastography (RT-SWE), a recent technique developed for soft tissue imaging. Written informed consent for RT-SWE was obtained from all eligible patients, who were healthy women aged between 19 and 52 y. Young's moduli of the breast tissue in the early follicular, late phase and luteal phase were compared. There were no significant differences in the mean, maximum and minimum elasticity values (Emean, Emax and Emin) and standard deviation (ESD). RT-SWE of glandular tissue revealed that ESD was increased in the early follicular phase compared with the luteal phase. Means ± SD of Emin, Emax and Emean in glandular tissue were 5.174 ± 2.138, 8.308 ± 3.166 and 6.593 ± 2.510, respectively, and in adipose tissue, 3.589 ± 2.083, 6.733 ± 3.522 and 4.857 ± 2.564, respectively. There were no significant differences in stiffness between glandular and adipose tissues throughout the menstrual cycle, but glandular tissue stiffness was lower in the luteal phase than in the early follicular phase. On the basis of these observations in normal healthy women, we believe we have obtained sufficient information to establish the baseline changes in human breast elasticity during the menstrual cycle. In the future, we intend to compare the elasticity values of healthy breast tissue with those of breast tissue affected by various pathologies. Our results reveal the significant potential of RT-SWE in the rapid and non-invasive clinical diagnosis of breast diseases, such as breast cancers. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Sensitivity of snowpack storage to precipitation and temperature using spatial and temporal analog models

NASA Astrophysics Data System (ADS)

Luce, Charles H.; Lopez-Burgos, Viviana; Holden, Zachary

2014-12-01

Empirical sensitivity analyses are important for evaluation of the effects of a changing climate on water resources and ecosystems. Although mechanistic models are commonly applied for evaluation of climate effects for snowmelt, empirical relationships provide a first-order validation of the various postulates required for their implementation. Previous studies of empirical sensitivity for April 1 snow water equivalent (SWE) in the western United States were developed by regressing interannual variations in SWE to winter precipitation and temperature. This offers a temporal analog for climate change, positing that a warmer future looks like warmer years. Spatial analogs are used to hypothesize that a warmer future may look like warmer places, and are frequently applied alternatives for complex processes, or states/metrics that show little interannual variability (e.g., forest cover). We contrast spatial and temporal analogs for sensitivity of April 1 SWE and the mean residence time of snow (SRT) using data from 524 Snowpack Telemetry (SNOTEL) stations across the western U.S. We built relatively strong models using spatial analogs to relate temperature and precipitation climatology to snowpack climatology (April 1 SWE, R2=0.87, and SRT, R2=0.81). Although the poorest temporal analog relationships were in areas showing the highest sensitivity to warming, spatial analog models showed consistent performance throughout the range of temperature and precipitation. Generally, slopes from the spatial relationships showed greater thermal sensitivity than the temporal analogs, and high elevation stations showed greater vulnerability using a spatial analog than shown in previous modeling and sensitivity studies. The spatial analog models provide a simple perspective to evaluate potential futures and may be useful in further evaluation of snowpack with warming.

Spatio-temporal variability of snow water equivalent in the extra-tropical Andes Cordillera from distributed energy balance modeling and remotely sensed snow cover

NASA Astrophysics Data System (ADS)

Cornwell, E.; Molotch, N. P.; McPhee, J.

2016-01-01

Seasonal snow cover is the primary water source for human use and ecosystems along the extratropical Andes Cordillera. Despite its importance, relatively little research has been devoted to understanding the properties, distribution and variability of this natural resource. This research provides high-resolution (500 m), daily distributed estimates of end-of-winter and spring snow water equivalent over a 152 000 km2 domain that includes the mountainous reaches of central Chile and Argentina. Remotely sensed fractional snow-covered area and other relevant forcings are combined with extrapolated data from meteorological stations and a simplified physically based energy balance model in order to obtain melt-season melt fluxes that are then aggregated to estimate the end-of-winter (or peak) snow water equivalent (SWE). Peak SWE estimates show an overall coefficient of determination R2 of 0.68 and RMSE of 274 mm compared to observations at 12 automatic snow water equivalent sensors distributed across the model domain, with R2 values between 0.32 and 0.88. Regional estimates of peak SWE accumulation show differential patterns strongly modulated by elevation, latitude and position relative to the continental divide. The spatial distribution of peak SWE shows that the 4000-5000 m a.s.l. elevation band is significant for snow accumulation, despite having a smaller surface area than the 3000-4000 m a.s.l. band. On average, maximum snow accumulation is observed in early September in the western Andes, and in early October on the eastern side of the continental divide. The results presented here have the potential of informing applications such as seasonal forecast model assessment and improvement, regional climate model validation, as well as evaluation of observational networks and water resource infrastructure development.

An investigation of the role of winter and spring precipitation as drivers of streamflow in the Missouri River Headwaters using tree-ring reconstructions

NASA Astrophysics Data System (ADS)

Frederick, S. E.; Woodhouse, C. A.; Martin, J. T.; Pederson, G. T.

2017-12-01

The Missouri River supplies water to over 3 million basin residents and is a driving force for the nation's agricultural and energy sectors. However, with changing climate and declining snowpack in western North America, seasonal water yields are becoming less predictable, revealing a gap in our understanding of regional hydroclimate and drivers of streamflow within the basin. By analyzing the relationship between seasonal precipitation and streamflow in the Missouri River Headwaters sub-basin, this study seeks to expand our knowledge based on the instrumental record alone. Here we present the first annually-resolved tree-ring reconstruction of spring precipitation for the Missouri River Headwaters. This reconstruction along with existing tree-ring reconstructions of April 1 snow-water equivalence (SWE) (Pederson et al. 2011) and natural streamflow (Martin, J.T. & Pederson, G.T., personal communication, June 2017) are used to test the feasibility of detecting a variable influence of winter and spring precipitation on streamflow over past centuries, and relative to the modern period. Initial analyses indicate that April 1 SWE is a significant control on streamflow, however, the April 1 SWE record does not fully account for anomalies observed in the streamflow record. This study therefore seeks to determine whether spring precipitation can account for some of this asynchronous variability observed between the April 1 SWE and streamflow records. Aside from improved understanding of the relationship between hydroclimate and streamflow in the headwaters of the Missouri River, our findings offer insights relating to changing contributions from snowmelt and spring precipitation, and long-term hydrologic variability and trends relevant to water resource management and planning efforts.

Cholinergic neurodegeneration in an Alzheimer mouse model overexpressing amyloid-precursor protein with the Swedish-Dutch-Iowa mutations.

PubMed

Foidl, Bettina Maria; Do-Dinh, Patricia; Hutter-Schmid, Bianca; Bliem, Harald R; Humpel, Christian

2016-12-01

Alzheimer's disease (AD) is a chronic neurodegenerative disorder that is mainly characterized by beta-amyloid (Aβ) plaque deposition, Tau pathology and dysfunction of the cholinergic system causing memory impairment. The aim of the present study was to examine (1) anxiety and cognition, (2) Aβ plaque deposition and (3) degeneration of cholinergic neurons in the nucleus basalis of Meynert (nbM) and cortical cholinergic innervation in an Alzheimer mouse model (APP_SweDI; overexpressing amyloid precursor protein (APP) with the Swedish K670N/M671L, Dutch E693Q, and Iowa D694N mutations). Our results show that 12-month-old APP_SweDI mice were more anxious and had more memory impairment. A large number of Aβ plaques were already visible at the age of 6 months and increased with age. A significant decrease in cholinergic neurons was seen in the transgenic mouse model in comparison to the wild-type mice, identified by immunohistochemistry against choline acetyltransferase (ChAT) and p75 neurotrophin receptor as well as by in situ hybridization. Moreover, a significant decrease in cortical cholinergic fiber density was found in the transgenic mice as compared to the wild-type. In the cerebral cortex of APP_SweDI mice, swollen cholinergic varicosities were seen in the vicinity of Aβ plaques. In conclusion, the present study shows that in an AD mouse model (APP_SweDI mice) a high Aβ plaque load in the cortex causes damage to cholinergic axons in the cortex, followed by subsequent retrograde-induced cell death of cholinergic neurons and some forms of compensatory processes. This degeneration was accompanied by enhanced anxiety and impaired cognition. Copyright © 2016 Elsevier Inc. All rights reserved.

The Geospatial Web and Local Geographical Education

ERIC Educational Resources Information Center

Harris, Trevor M.; Rouse, L. Jesse; Bergeron, Susan J.

2010-01-01

Recent innovations in the Geospatial Web represent a paradigm shift in Web mapping by enabling educators to explore geography in the classroom by dynamically using a rapidly growing suite of impressive online geospatial tools. Coupled with access to spatial data repositories and User-Generated Content, the Geospatial Web provides a powerful…

WEB-BASED MODELING OF A FERTILIZER SOLUTION SPILL IN THE OHIO RIVER

EPA Science Inventory

Environmental computer models are usually desktop models. Some web-enabled models are beginning to appear where the user can use a browser to run the models on a central web server. Several issues arise when a desktop model is transferred to a web architecture. This paper discuss...

Designing, Implementing, and Evaluating Secure Web Browsers

ERIC Educational Resources Information Center

Grier, Christopher L.

2009-01-01

Web browsers are plagued with vulnerabilities, providing hackers with easy access to computer systems using browser-based attacks. Efforts that retrofit existing browsers have had limited success since modern browsers are not designed to withstand attack. To enable more secure web browsing, we design and implement new web browsers from the ground…

Integrating sea floor observatory data: the EMSO data infrastructure

NASA Astrophysics Data System (ADS)

Huber, Robert; Azzarone, Adriano; Carval, Thierry; Doumaz, Fawzi; Giovanetti, Gabriele; Marinaro, Giuditta; Rolin, Jean-Francois; Beranzoli, Laura; Waldmann, Christoph

2013-04-01

The European research infrastructure EMSO is a European network of fixed-point, deep-seafloor and water column observatories deployed in key sites of the European Continental margin and Arctic. It aims to provide the technological and scientific framework for the investigation of the environmental processes related to the interaction between the geosphere, biosphere, and hydrosphere and for a sustainable management by long-term monitoring also with real-time data transmission. Since 2006, EMSO is on the ESFRI (European Strategy Forum on Research Infrastructures) roadmap and has entered its construction phase in 2012. Within this framework, EMSO is contributing to large infrastructure integration projects such as ENVRI and COOPEUS. The EMSO infrastructure is geographically distributed in key sites of European waters, spanning from the Arctic, through the Atlantic and Mediterranean Sea to the Black Sea. It is presently consisting of thirteen sites which have been identified by the scientific community according to their importance respect to Marine Ecosystems, Climate Changes and Marine GeoHazards. The data infrastructure for EMSO is being designed as a distributed system. Presently, EMSO data collected during experiments at each EMSO site are locally stored and organized in catalogues or relational databases run by the responsible regional EMSO nodes. Three major institutions and their data centers are currently offering access to EMSO data: PANGAEA, INGV and IFREMER. In continuation of the IT activities which have been performed during EMSOs twin project ESONET, EMSO is now implementing the ESONET data architecture within an operational EMSO data infrastructure. EMSO aims to be compliant with relevant marine initiatives such as MyOceans, EUROSITES, EuroARGO, SEADATANET and EMODNET as well as to meet the requirements of international and interdisciplinary projects such as COOPEUS and ENVRI, EUDAT and iCORDI. A major focus is therefore set on standardization and interoperability of the EMSO data infrastructure. Beneath common standards for metadata exchange such as OpenSearch or OAI-PMH, EMSO has chosen to implement core standards of the Open Geospatial Consortium (OGC) Sensor Web Enablement (SWE) suite of standards, such as Catalogue Service for Web (CS-W), Sensor Observation Service (SOS) and Observations and Measurements (O&M). Further, strong integration efforts are currently undertaken to harmonize data formats e.g NetCDF as well as the used ontologies and terminologies. The presentation will also give information to users about the discovery and visualization procedure for the EMSO data presently available.

Ubiquitous Computing Services Discovery and Execution Using a Novel Intelligent Web Services Algorithm

PubMed Central

Choi, Okkyung; Han, SangYong

2007-01-01

Ubiquitous Computing makes it possible to determine in real time the location and situations of service requesters in a web service environment as it enables access to computers at any time and in any place. Though research on various aspects of ubiquitous commerce is progressing at enterprises and research centers, both domestically and overseas, analysis of a customer's personal preferences based on semantic web and rule based services using semantics is not currently being conducted. This paper proposes a Ubiquitous Computing Services System that enables a rule based search as well as semantics based search to support the fact that the electronic space and the physical space can be combined into one and the real time search for web services and the construction of efficient web services thus become possible.

Development of a Web-Enabled Learning Platform for Geospatial Laboratories: Improving the Undergraduate Learning Experience

ERIC Educational Resources Information Center

Mui, Amy B.; Nelson, Sarah; Huang, Bruce; He, Yuhong; Wilson, Kathi

2015-01-01

This paper describes a web-enabled learning platform providing remote access to geospatial software that extends the learning experience outside of the laboratory setting. The platform was piloted in two undergraduate courses, and includes a software server, a data server, and remote student users. The platform was designed to improve the quality…

Augmenting Research, Education, and Outreach with Client-Side Web Programming.

PubMed

Abriata, Luciano A; Rodrigues, João P G L M; Salathé, Marcel; Patiny, Luc

2018-05-01

The evolution of computing and web technologies over the past decade has enabled the development of fully fledged scientific applications that run directly on web browsers. Powered by JavaScript, the lingua franca of web programming, these 'web apps' are starting to revolutionize and democratize scientific research, education, and outreach. Copyright © 2017 Elsevier Ltd. All rights reserved.

Matsu: An Elastic Cloud Connected to a SensorWeb for Disaster Response

NASA Technical Reports Server (NTRS)

Mandl, Daniel

2011-01-01

This slide presentation reviews the use of cloud computing combined with the SensorWeb in aiding disaster response planning. Included is an overview of the architecture of the SensorWeb, and overviews of the phase 1 of the EO-1 system and the steps to improve it to transform it to an On-demand product cloud as part of the Open Cloud Consortium (OCC). The effectiveness of this system is demonstrated in the SensorWeb for the Namibia flood in 2010, using information blended from MODIS, TRMM, River Gauge data, and the Google Earth version of Namibia the system enabled river surge predictions and could enable planning for future disaster responses.

Environmental Response Laboratory Network (ERLN) WebEDR Quick Reference Guide

EPA Pesticide Factsheets

The Web Electronic Data Review is a web-based system that performs automated data processing on laboratory-submitted Electronic Data Deliverables (EDDs). Enables users to perform technical audits on data, and against Measurement Quality Objectives (MQOs).

Linguistic constraints on children's overt marking of BE by dialect and age.

PubMed

Roy, Joseph; Oetting, Janna B; Moland, Christy Wynn

2013-06-01

Overt marking of BE in nonmainstream adult dialects of English is influenced by a number of linguistic constraints, including the structure's person, number, tense, contractibility, and grammatical function. In the current study, the authors examined the effects of these constraints on overt marking of BE in children as a function of their nonmainstream English dialect and age. The data were language samples from 62 children, ages 4-6 years; 24 children spoke African American English (AAE), and 38 spoke Southern White English (SWE). Analyses included analysis of variance and logistic regression. Rates of overt marking varied by the children's dialect but not their age. Although the person, number, tense, and grammatical function of BE influenced the children's rates of marking, the nature and magnitude of the influence differed by the children's dialect. For AAE-speaking children, contractibility also influenced their marking of BE. Consistent with the adult literature, the current study showed that AAE- and SWE-speaking children marked BE in ways that differed from each other and from what has been documented for child speakers of Mainstream American English. These findings show stability in the use of BE in AAE and SWE that spans different generations and different dialect communities.

Linguistic Constraints on Children's Overt Marking of BE by Dialect and Age

PubMed Central

Roy, Joseph; Oetting, Janna B.; Moland, Christy Wynn

2013-01-01

Purpose Overt marking of BE in nonmainstream adult dialects of English is influenced by a number of linguistic constraints, including the structure's person, number, tense, contractibility, and grammatical function. In the current study, we examined the effects of these constraints on overt marking of BE in children as a function of their nonmainstream English dialect and age. Methods The data were language samples from 62 children, aged four to six years; 24 spoke African American English (AAE) and 38 spoke Southern White English (SWE). Analyses included analysis of variance and logistic regression. Results Rates of overt marking varied by the children's dialect but not their age. Although the person, number, tense, and grammatical function of BE influenced the children's rates of marking, the nature and magnitude of the influence differed by the children's dialect. For AAE-speaking children, contractibility also influenced their marking of BE. Conclusions Consistent with the adult literature, the AAE- and SWE-speaking children marked BE in ways that differed from each other and from what has been documented for child speakers of Mainstream American English. These findings show stability in the use of BE in AAE and SWE that spans different generations and different dialect communities. PMID:23275400

[Assessment of plantar fasciitis using shear wave elastography].

PubMed

Zhang, Lining; Wan, Wenbo; Zhang, Lihai; Xiao, Hongyu; Luo, Yukun; Fei, Xiang; Zheng, Zhixin; Tang, Peifu

2014-02-01

To assess the stiffness and thickness of the plantar fascia using shear wave elastography (SWE) in healthy volunteers of different ages and in patients with plantar fasciitis. The bilateral feet of 30 healthy volunteers and 23 patients with plantar fasciitis were examined with SWE. The plantar fascia thickness and elasticity modulus value were measured at the insertion of the calcaneus and at 1 cm from the insertion. The elderly volunteers had a significantly greater plantar fascia thickness measured using conventional ultrasound (P=0.005) and a significantly lower elasticity modulus value than the young volunteers (P=0.000). The patients with fasciitis had a significantly greater plantar fascia thickness (P=0.001) and a lower elasticity modulus value than the elderly volunteers (P=0.000). The elasticity modulus value was significantly lower at the calcaneus insertion than at 1 cm from the insertion in patients with fasciitis (P=0.000) but showed no significantly difference between the two points in the elderly or young volunteers (P=0.172, P=0.126). SWE allows quantitative assessment of the stiffness of the plantar fascia, which decreases with aging and in patients with plantar fasciitis.

Evaluation of fatty liver fibrosis in rabbits using real-time shear wave elastography

PubMed Central

LU, YONGPING; WEI, JIA; TANG, YUEYUE; YUAN, YUAN; HUANG, YANLING; ZHANG, YONG; LI, YUNYAN

2014-01-01

The aim of the present study was to detect the elastic modulus (stiffness) of the livers of rabbits with non-alcoholic and alcoholic fatty liver disease using real-time shear wave elastography (SWE), and to investigate the fibrosis development process in the formation of fatty liver. The stiffness of the fatty livers in rabbit models prepared via feeding with alcohol or a high-fat diet were measured using a real-time SWE ultrasound system and a 4–15-MHz linear array probe, and the liver stiffness was compared with the pathological staging of the disease. The stiffness of the liver was positively correlated with the degree of pathological change in fatty liver disease (P<0.01). The stiffness of the liver in the alcoholic fatty liver group was higher compared with that in the non-alcoholic fatty liver and control groups, and the stiffness in the non-alcoholic fatty liver group was higher than that in the control group (P<0.01). Real-time SWE objectively identified the trend in the changing stiffness of the liver and noninvasively detected the development of fibrosis in the progression of non-alcoholic and alcoholic fatty liver disease. PMID:25009583

Ensemble-based assimilation of fractional snow-covered area satellite retrievals to estimate the snow distribution at Arctic sites

NASA Astrophysics Data System (ADS)

Aalstad, Kristoffer; Westermann, Sebastian; Vikhamar Schuler, Thomas; Boike, Julia; Bertino, Laurent

2018-01-01

With its high albedo, low thermal conductivity and large water storing capacity, snow strongly modulates the surface energy and water balance, which makes it a critical factor in mid- to high-latitude and mountain environments. However, estimating the snow water equivalent (SWE) is challenging in remote-sensing applications already at medium spatial resolutions of 1 km. We present an ensemble-based data assimilation framework that estimates the peak subgrid SWE distribution (SSD) at the 1 km scale by assimilating fractional snow-covered area (fSCA) satellite retrievals in a simple snow model forced by downscaled reanalysis data. The basic idea is to relate the timing of the snow cover depletion (accessible from satellite products) to the peak SSD. Peak subgrid SWE is assumed to be lognormally distributed, which can be translated to a modeled time series of fSCA through the snow model. Assimilation of satellite-derived fSCA facilitates the estimation of the peak SSD, while taking into account uncertainties in both the model and the assimilated data sets. As an extension to previous studies, our method makes use of the novel (to snow data assimilation) ensemble smoother with multiple data assimilation (ES-MDA) scheme combined with analytical Gaussian anamorphosis to assimilate time series of Moderate Resolution Imaging Spectroradiometer (MODIS) and Sentinel-2 fSCA retrievals. The scheme is applied to Arctic sites near Ny-Ålesund (79° N, Svalbard, Norway) where field measurements of fSCA and SWE distributions are available. The method is able to successfully recover accurate estimates of peak SSD on most of the occasions considered. Through the ES-MDA assimilation, the root-mean-square error (RMSE) for the fSCA, peak mean SWE and peak subgrid coefficient of variation is improved by around 75, 60 and 20 %, respectively, when compared to the prior, yielding RMSEs of 0.01, 0.09 m water equivalent (w.e.) and 0.13, respectively. The ES-MDA either outperforms or at least nearly matches the performance of other ensemble-based batch smoother schemes with regards to various evaluation metrics. Given the modularity of the method, it could prove valuable for a range of satellite-era hydrometeorological reanalyses.

Evaluation of an assimilation scheme to estimate snow water equivalent in the High Atlas of Morocco.

NASA Astrophysics Data System (ADS)

Baba, W. M.; Baldo, E.; Gascoin, S.; Margulis, S. A.; Cortés, G.; Hanich, L.

2017-12-01

The snow melt from the Atlas mountains represents a crucial water resource for crop irrigation in Morocco. Due to the paucity of in situ measurements, and the high spatial variability of the snow cover in this semi-arid region, assimilation of snow cover area (SCA) from high resolution optical remote sensing into a snowpack energy-balance model is considered as a promising method to estimate the snow water equivalent (SWE) and snow melt at catchment scales. Here we present a preliminary evaluation of an uncalibrated particle batch smoother data assimilation scheme (Margulis et al., 2015, J. Hydrometeor., 16, 1752-1772) in the High-Atlas Rheraya pilot catchment (225 km2) over a snow season. This approach does not require in situ data since it is based on MERRA-2 reanalyses data and satellite fractional snow cover area data. We compared the output of this prior/posterior ensemble data assimilation system to output from the distributed snowpack evolution model SnowModel (Liston and Elder, 2006, J. Hydrometeor. 7, 1259-1276). SnowModel was forced with in situ meteorological data from five automatic weather stations (AWS) and some key parameters (precipitation correction factor and rain-snow phase transition parameters) were calibrated using a time series of 8-m resolution SCA maps from Formosat-2. The SnowModel simulation was validated using a continuous snow height record at one high elevation AWS. The results indicate that the open loop simulation was reasonably accurate (compared to SnowModel results) in spite of the coarse resolution of the MERRA-2 forcing. The assimilation of Formosat-2 SCA further improved the simulation in terms of the peak SWE and SWE evolution over the melt season. During the accumulation season, the differences between the modeled and estimated (posterior) SWE were more substantial. The differences appear to be due to some observed precipitation events not being captured in MERRA-2. Further investigation will determine whether additional improvement in the posterior estimates result from a calibration of uncertainty input parameters based on the in situ meteorological data. The positive preliminary results pave the way for a SWE reanalysis at the scale of the Atlas mountains using data from wide swath sensors such as Landsat and Sentinel-2.

Anthropogenic Warming Impacts on Today's Sierra Nevada Snowpack and Flood Severity

NASA Astrophysics Data System (ADS)

Huang, X.; Hall, A. D.; Berg, N.

2017-12-01

Focusing on this recent extreme wet year over California, this study investigates the warming impacts on the snowpack and the flood severity over the Sierra Nevada (SN), where the majority of the precipitation occurs during the winter season and early spring. One of our goals is to quantify anthropogenic warming impacts on the snow water equivalent (SWE) including recent historical warming and prescribed future projected warming scenarios; This work also explores to what extent flooding risk has increased under those warming cases. With a good representation of the historical precipitation and snowpack over the Sierra Nevada from the historical reference run at 9km (using WRF), the results from the offline Noah-MP simulations with perturbed near-surface temperatures reveal magnificent impacts of warming to the loss of the average snowpack. The reduction of the SWE under warming mainly results from the decreased rain-to-snow conversion with a weaker effect from increased snowmelt. Compared to the natural case, the past industrial warming decreased the maximum SWE by about one-fifth averaged over the study area. Future continuing warming can result in around one-third reduction of current maximum SWE under RCP4.5 emissions scenario, and the loss can reach to two-thirds under RCP8.5 as a "business-as-usual" condition. The impact of past warming is particularly outstanding over the North SN region where precipitation dominates and over the middle elevation regions where the snow mainly distributes. In the future, the warming impact on SWE progresses to higher regions, and so to the south and east. Under the business-as-usual scenario, the projected mid-elevation snowpack almost disappears by April 1st with even high-elevation snow reduced by about half. Along with the loss of the snowpack, as the temperature warms, floods can also intensify with increased early season runoff especially under heavy-rainy days caused by the weakened rain-to-snow processes and strengthened snow-melt mainly over the mid-elevation region. Under continuing warming and predicted intensified precipitation extremes in the coming century, the severity of floods can become much more disastrous and potentially shift from the north (where the Oroville Dam spillway emergency occurred this February) to the central and south SN regions.

Shear wave elastography in medullary thyroid carcinoma diagnostics

PubMed Central

Gumińska, Anna; Bakuła-Zalewska, Elwira; Mlosek, Krzysztof; Słapa, Rafał Z.; Wareluk, Paweł; Krauze, Agnieszka; Ziemiecka, Agnieszka; Migda, Bartosz; Jakubowski, Wiesław; Dedecjus, Marek

2015-01-01

Shear wave elastography (SWE) is a modern method for the assessment of tissue stiffness. There has been a growing interest in the use of this technique for characterizing thyroid focal lesions, including preoperative diagnostics. Aim The aim of the study was to assess the clinical usefulness of SWE in medullary thyroid carcinoma (MTC) diagnostics. Materials and methods A total of 169 focal lesions were identified in the study group (139 patients), including 6 MTCs in 4 patients (mean age: 45 years). B-mode ultrasound and SWE were performed using Aixplorer (SuperSonic, Aix-en-Provence), with a 4–15 MHz linear probe. The ultrasound was performed to assess the echogenicity and echostructure of the lesions, their margin, the halo sign, the height/width ratio (H/W ratio), the presence of calcifications and the vascularization pattern. This was followed by an analysis of maximum and mean Young's (E) modulus values for MTC (EmaxLR, EmeanLR) and the surrounding thyroid tissues (EmaxSR, EmeanSR), as well as mean E-values (EmeanLRz) for 2 mm region of interest in the stiffest zone of the lesion. The lesions were subject to pathological and/or cytological evaluation. Results The B-mode assessment showed that all MTCs were hypoechogenic, with no halo sign, and they contained micro- and/ or macrocalcifications. Ill-defined lesion margin were found in 4 out of 6 cancers; 4 out of 6 cancers had a H/W ratio > 1. Heterogeneous echostructure and type III vascularity were found in 5 out of 6 lesions. In the SWE, the mean value of EmaxLR for all of the MTCs was 89.5 kPa and (the mean value of EmaxSR for all surrounding tissues was) 39.7 kPa Mean values of EmeanLR and EmeanSR were 34.7 kPa and 24.4 kPa, respectively. The mean value of EmeanLRz was 49.2 kPa. Conclusions SWE showed MTCs as stiffer lesions compared to the surrounding tissues. The lesions were qualified for fine needle aspiration biopsy based on B-mode assessment. However, the diagnostic algorithm for MTC is based on the measurement of serum calcitonin levels, B-mode ultrasound and FNAB. PMID:26807293

Prospective Validation of Intra- and Interobserver Reproducibility of a New Point Shear Wave Elastographic Technique for Assessing Liver Stiffness in Patients with Chronic Liver Disease.

PubMed

Ahn, Su Joa; Lee, Jeong Min; Chang, Won; Lee, Sang Min; Kang, Hyo-Jin; Yang, Hyunkyung; Yoon, Jeong Hee; Park, Sae Jin; Han, Joon Koo

2017-01-01

To assess intra- and inter-observer reproducibility of a new point shear wave elastography technique (pSWE, S-Shearwave, Samsung Medison) and compare its accuracy in assessing liver stiffness (LS) with an established pSWE technique (Virtual Touch Quantification, VTQ). Thirty-three patients were enrolled in this Institutional Review Board-approved prospective study. LS values were measured by VTQ on an Acuson S2000 system (Siemens Healthineer) and S-Shearwave on an RS-80A (Samsung Medison) in the same session, followed by two further S-Shearwave sessions for inter- and intra-observer variation at 8-hour intervals. The technical success rate (SR) and reliability of the measurements of both pSWE techniques were compared. The intra- and inter-observer reproducibility of S-Shearwave was determined by intraclass correlation coefficients (ICCs). LS values were measured by both methods of pSWE. The diagnostic performance in severe fibrosis (F ≥ 3) and cirrhosis (F = 4) was evaluated using the receiver operating characteristics curve analysis and the Obuchowski measure with the LS values of transient elastography as the referenced standard. The VTQ (100%, 33/33) and S-Shearwave (96.9%, 32/33) techniques did not display a significant difference in technical SR ( p = 0.63) or reliability of LS measurements (96.9%, 32/33; 93.9%, 30/32, respectively, p = 0.61). The inter- and intra-observer agreement for LS measurements using the S-Shearwave technique was excellent (ICC = 0.98 and 0.99, respectively). The mean LS values of both pSWE techniques were not significantly different and exhibited a good correlation (r = 0.78). To detect F ≥ 3 and F = 4, VTQ and S-Shearwave showed comparable diagnostic accuracy as indicated by the following outcomes: areas under receiver operating characteristics curve (AUROC) = 0.87 (95% confidence intervals [CI] 0.70-0.96), 0.89 for VTQ (95% CI 0.74-0.97), respectively; and AUROC = 0.84 (95% CI 0.67-0.94), 0.94 (95% CI 0.80-0.99) for S-Shearwave (p > 0.48), respectively. The Obuchowski measures were similarly high for S-Shearwave and VTQ (0.94 vs. 0.95). S-Shearwave shows excellent inter- and intra-observer agreement and diagnostic effectiveness comparable to VTQ in detecting LS.

Impact Evaluation of Enabling Mothers to Prevent Pediatric Obesity through Web-Based Education and Reciprocal Determinism (EMPOWER) Randomized Control Trial

ERIC Educational Resources Information Center

Knowlden, Adam P.; Sharma, Manoj; Cottrell, Randall R.; Wilson, Bradley R. A.; Johnson, Marcus Lee

2015-01-01

Background. The family and home environment is an influential antecedent of childhood obesity. The purpose of this study was to pilot test The Enabling Mothers to Prevent Pediatric Obesity through Web-Based Education and Reciprocal Determinism (EMPOWER) intervention; a newly developed, theory-based, online program for prevention of childhood…

Applying Web-Enabled Problem-Based Learning and Self-Regulated Learning to Add Value to Computing Education in Taiwan's Vocational Schools

ERIC Educational Resources Information Center

Lee, Tsang-Hsiung; Shen, Pei-Di; Tsai, Chia-Wen

2008-01-01

This article describes the design and delivery of a compulsory course in packaged software at vocational schools in Taiwan. A course website was devised and deployed to supplement learning activities in the traditional classroom. A series of quasi-experiments was conducted with innovative instructional designs, that is, web-enabled problem-based…

Development of a Web-Enabled Informatics Platform for Manipulation of Gene Expression Data

DTIC Science & Technology

2004-12-01

genomic platforms such as metabolomics and proteomics , and to federated databases for knowledge management. A successful SBIR Phase I completed...measurements that require sophisticated bioinformatic platforms for data archival, management, integration, and analysis if researchers are to derive...web-enabled bioinformatic platform consisting of a Laboratory Information Management System (LIMS), an Analysis Information Management System (AIMS

Developing Long-Term Computing Skills among Low-Achieving Students via Web-Enabled Problem-Based Learning and Self-Regulated Learning

ERIC Educational Resources Information Center

Tsai, Chia-Wen; Lee, Tsang-Hsiung; Shen, Pei-Di

2013-01-01

Many private vocational schools in Taiwan have taken to enrolling students with lower levels of academic achievement. The authors re-designed a course and conducted a series of quasi-experiments to develop students' long-term computing skills, and examined the longitudinal effects of web-enabled, problem-based learning (PBL) and self-regulated…

WebVR: an interactive web browser for virtual environments

NASA Astrophysics Data System (ADS)

Barsoum, Emad; Kuester, Falko

2005-03-01

The pervasive nature of web-based content has lead to the development of applications and user interfaces that port between a broad range of operating systems and databases, while providing intuitive access to static and time-varying information. However, the integration of this vast resource into virtual environments has remained elusive. In this paper we present an implementation of a 3D Web Browser (WebVR) that enables the user to search the internet for arbitrary information and to seamlessly augment this information into virtual environments. WebVR provides access to the standard data input and query mechanisms offered by conventional web browsers, with the difference that it generates active texture-skins of the web contents that can be mapped onto arbitrary surfaces within the environment. Once mapped, the corresponding texture functions as a fully integrated web-browser that will respond to traditional events such as the selection of links or text input. As a result, any surface within the environment can be turned into a web-enabled resource that provides access to user-definable data. In order to leverage from the continuous advancement of browser technology and to support both static as well as streamed content, WebVR uses ActiveX controls to extract the desired texture skin from industry strength browsers, providing a unique mechanism for data fusion and extensibility.

Interactive, Secure Web-enabled Aircraft Engine Simulation Using XML Databinding Integration

NASA Technical Reports Server (NTRS)

Lin, Risheng; Afjeh, Abdollah A.

2003-01-01

This paper discusses the detailed design of an XML databinding framework for aircraft engine simulation. The framework provides an object interface to access and use engine data. while at the same time preserving the meaning of the original data. The Language independent representation of engine component data enables users to move around XML data using HTTP through disparate networks. The application of this framework is demonstrated via a web-based turbofan propulsion system simulation using the World Wide Web (WWW). A Java Servlet based web component architecture is used for rendering XML engine data into HTML format and dealing with input events from the user, which allows users to interact with simulation data from a web browser. The simulation data can also be saved to a local disk for archiving or to restart the simulation at a later time.

A Vision for an International Multi-Sensor Snow Observing Mission

NASA Technical Reports Server (NTRS)

Kim, Edward

2015-01-01

Discussions within the international snow remote sensing community over the past two years have led to encouraging consensus regarding the broad outlines of a dedicated snow observing mission. The primary consensus - that since no single sensor type is satisfactory across all snow types and across all confounding factors, a multi-sensor approach is required - naturally leads to questions about the exact mix of sensors, required accuracies, and so on. In short, the natural next step is to collect such multi-sensor snow observations (with detailed ground truth) to enable trade studies of various possible mission concepts. Such trade studies must assess the strengths and limitations of heritage as well as newer measurement techniques with an eye toward natural sensitivity to desired parameters such as snow depth and/or snow water equivalent (SWE) in spite of confounding factors like clouds, lack of solar illumination, forest cover, and topography, measurement accuracy, temporal and spatial coverage, technological maturity, and cost.

VisBOL: Web-Based Tools for Synthetic Biology Design Visualization.

PubMed

McLaughlin, James Alastair; Pocock, Matthew; Mısırlı, Göksel; Madsen, Curtis; Wipat, Anil

2016-08-19

VisBOL is a Web-based application that allows the rendering of genetic circuit designs, enabling synthetic biologists to visually convey designs in SBOL visual format. VisBOL designs can be exported to formats including PNG and SVG images to be embedded in Web pages, presentations and publications. The VisBOL tool enables the automated generation of visualizations from designs specified using the Synthetic Biology Open Language (SBOL) version 2.0, as well as a range of well-known bioinformatics formats including GenBank and Pigeoncad notation. VisBOL is provided both as a user accessible Web site and as an open-source (BSD) JavaScript library that can be used to embed diagrams within other content and software.

Security and Efficiency Concerns With Distributed Collaborative Networking Environments

DTIC Science & Technology

2003-09-01

have the ability to access Web communications services of the WebEx MediaTone Network from a single login. [24] WebEx provides a range of secure...Web. WebEx services enable secure data, voice and video communications through the browser and are supported by the WebEx MediaTone Network, a global...designed to host large-scale, structured events and conferences, featuring a Q&A Manager that allows multiple moderators to handle questions while

One-Year Efficacy Testing of Enabling Mothers to Prevent Pediatric Obesity through Web-Based Education and Reciprocal Determinism (EMPOWER) Randomized Control Trial

ERIC Educational Resources Information Center

Knowlden, Adam; Sharma, Manoj

2016-01-01

Background: The purpose of this study was to evaluate the efficacy of the Enabling Mothers to Prevent Pediatric Obesity through Web-Based Education and Reciprocal Determinism (EMPOWER) intervention at 1-year, postintervention follow-up. Method: A mixed between-within subjects design was used to evaluate the trial. Independent variables included a…

Web services as applications' integration tool: QikProp case study.

PubMed

Laoui, Abdel; Polyakov, Valery R

2011-07-15

Web services are a new technology that enables to integrate applications running on different platforms by using primarily XML to enable communication among different computers over the Internet. Large number of applications was designed as stand alone systems before the concept of Web services was introduced and it is a challenge to integrate them into larger computational networks. A generally applicable method of wrapping stand alone applications into Web services was developed and is described. To test the technology, it was applied to the QikProp for DOS (Windows). Although performance of the application did not change when it was delivered as a Web service, this form of deployment had offered several advantages like simplified and centralized maintenance, smaller number of licenses, and practically no training for the end user. Because by using the described approach almost any legacy application can be wrapped as a Web service, this form of delivery may be recommended as a global alternative to traditional deployment solutions. Copyright © 2011 Wiley Periodicals, Inc.

Simple Web-based interactive key development software (WEBiKEY) and an example key for Kuruna (Poaceae: Bambusoideae).

PubMed

Attigala, Lakshmi; De Silva, Nuwan I; Clark, Lynn G

2016-04-01

Programs that are user-friendly and freely available for developing Web-based interactive keys are scarce and most of the well-structured applications are relatively expensive. WEBiKEY was developed to enable researchers to easily develop their own Web-based interactive keys with fewer resources. A Web-based multiaccess identification tool (WEBiKEY) was developed that uses freely available Microsoft ASP.NET technologies and an SQL Server database for Windows-based hosting environments. WEBiKEY was tested for its usability with a sample data set, the temperate woody bamboo genus Kuruna (Poaceae). WEBiKEY is freely available to the public and can be used to develop Web-based interactive keys for any group of species. The interactive key we developed for Kuruna using WEBiKEY enables users to visually inspect characteristics of Kuruna and identify an unknown specimen as one of seven possible species in the genus.

Evolving EO-1 Sensor Web Testbed Capabilities in Pursuit of GEOSS

NASA Technical Reports Server (NTRS)

Mandi, Dan; Ly, Vuong; Frye, Stuart; Younis, Mohamed

2006-01-01

A viewgraph presentation to evolve sensor web capabilities in pursuit of capabilities to support Global Earth Observing System of Systems (GEOSS) is shown. The topics include: 1) Vision to Enable Sensor Webs with "Hot Spots"; 2) Vision Extended for Communication/Control Architecture for Missions to Mars; 3) Key Capabilities Implemented to Enable EO-1 Sensor Webs; 4) One of Three Experiments Conducted by UMBC Undergraduate Class 12-14-05 (1 - 3); 5) Closer Look at our Mini-Rovers and Simulated Mars Landscae at GSFC; 6) Beginning to Implement Experiments with Standards-Vision for Integrated Sensor Web Environment; 7) Goddard Mission Services Evolution Center (GMSEC); 8) GMSEC Component Catalog; 9) Core Flight System (CFS) and Extension for GMSEC for Flight SW; 10) Sensor Modeling Language; 11) Seamless Ground to Space Integrated Message Bus Demonstration (completed December 2005); 12) Other Experiments in Queue; 13) Acknowledgements; and 14) References.

The Future of Web Maps in Next Generation Textbooks

NASA Astrophysics Data System (ADS)

DiBiase, D.; Prasad, S.

2014-12-01

The reformation of the "Object Formerly Known as Textbook" (coined by the Chronicle of Higher Education) toward a digital future is underway. Emerging nextgen texts look less like electronic books ("ebooks") and more like online courseware. In addition to text and illustrations, nextgen textbooks for STEM subjects are likely to combine quizzes, grade management tools, support for social learning, and interactive media including web maps. Web maps are interactive, multi-scale, online maps that enable teachers and learners to explore, interrogate, and mash up the wide variety of map layers available in the cloud. This presentation will show how web maps coupled with interactive quizzes enable students' purposeful explorations and interpretations of spatial patterns related to humankind's interactions with the earth. Attendees will also learn about Esri's offer to donate ArcGIS Online web mapping subscriptions to every U.S. school as part of the President Obama's ConnectED initiative.

Dynamic Generation of Reduced Ontologies to Support Resource Constraints of Mobile Devices

ERIC Educational Resources Information Center

Schrimpsher, Dan

2011-01-01

As Web Services and the Semantic Web become more important, enabling technologies such as web service ontologies will grow larger. At the same time, use of mobile devices to access web services has doubled in the last year. The ability of these resource constrained devices to download and reason across these ontologies to support service discovery…

A versatile and interoperable network sensors for water resources monitoring

NASA Astrophysics Data System (ADS)

Ortolani, Alberto; Brandini, Carlo; Costantini, Roberto; Costanza, Letizia; Innocenti, Lucia; Sabatini, Francesco; Gozzini, Bernardo

2010-05-01

Monitoring systems to assess water resources quantity and quality require extensive use of in-situ measurements, that have great limitations like difficulties to access and share data, and to customise and easy reconfigure sensors network to fulfil end-users needs during monitoring or crisis phases. In order to address such limitations Sensor Web Enablement technologies for sensors management have been developed and applied to different environmental context under the EU-funded OSIRIS project (Open architecture for Smart and Interoperable networks in Risk management based on In-situ Sensors, www.osiris-fp6.eu). The main objective of OSIRIS was to create a monitoring system to manage different environmental crisis situations, through an efficient data processing chain where in-situ sensors are connected via an intelligent and versatile network infrastructure (based on web technologies) that enables end-users to remotely access multi-domain sensors information. Among the project application, one was focused on underground fresh-water monitoring and management. With this aim a monitoring system to continuously and automatically check water quality and quantity has been designed and built in a pilot test, identified as a portion of the Amiata aquifer feeding the Santa Fiora springs (Grosseto, Italy). This aquifer present some characteristics that make it greatly vulnerable under some conditions. It is a volcanic aquifer with a fractured structure. The volcanic nature in Santa Fiora causes levels of arsenic concentrations that normally are very close to the threshold stated by law, but that sometimes overpass such threshold for reasons still not fully understood. The presence of fractures makes the infiltration rate very inhomogeneous from place to place and very high in correspondence of big fractures. In case of liquid-pollutant spills (typically hydrocarbons spills from tanker accidents or leakage from house tanks containing fuel for heating), these fractures can act as shortcuts to the heart of the aquifer, causing water contamination much faster than what inferable from average infiltration rates. A new system has been set up, upgrading a legacy sensor network with new sensors to address the monitoring and emergency phase management. Where necessary sensors have been modified in order to manage the whole sensor network through SWE services. The network manage sensors for water parameters (physical and chemical) and for atmospheric ones (for supporting the management of accidental crises). A main property of the developed architecture is that it can be easily reconfigured to pass from the monitoring to the alert phase, by changing sampling frequencies of interesting parameters, or deploying specific additional sensors on identified optimal positions (as in case of the hydrocarbon spill). A hydrogeological model, coupled through a hydrological interface to the atmospheric forcing, has been implemented for the area. Model products (accessed through the same web interface than sensors) give a fundamental added value to the upgraded sensors network (e.g. for data merging procedures). Together with the available measurements, it is shown how the model improves the knowledge of the local hydrogeological system, gives a fundamental support to eventually reconfigure the system (e.g. support on transportable sensors position). The network, basically conceived for real-time monitoring, allow to accumulate an unprecedent amount of information for the aquifer. The availability of such a large set of data (in terms of continuously measured water levels, fluxes, precipitation, concentrations, etc.) from the system, gives a unique opportunity for studying the influences of hydrogeological and geopedological parameters on arsenic and concentrations of other chemicals that are naturally present in water.

The Namibia Early Flood Warning System, A CEOS Pilot Project

NASA Technical Reports Server (NTRS)

Mandl, Daniel; Frye, Stuart; Cappelaere, Pat; Sohlberg, Robert; Handy, Matthew; Grossman, Robert

2012-01-01

Over the past year few years, an international collaboration has developed a pilot project under the auspices of Committee on Earth Observation Satellite (CEOS) Disasters team. The overall team consists of civilian satellite agencies. For this pilot effort, the development team consists of NASA, Canadian Space Agency, Univ. of Maryland, Univ. of Colorado, Univ. of Oklahoma, Ukraine Space Research Institute and Joint Research Center(JRC) for European Commission. This development team collaborates with regional , national and international agencies to deliver end-to-end disaster coverage. In particular, the team in collaborating on this effort with the Namibia Department of Hydrology to begin in Namibia . However, the ultimate goal is to expand the functionality to provide early warning over the South Africa region. The initial collaboration was initiated by United Nations Office of Outer Space Affairs and CEOS Working Group for Information Systems and Services (WGISS). The initial driver was to demonstrate international interoperability using various space agency sensors and models along with regional in-situ ground sensors. In 2010, the team created a preliminary semi-manual system to demonstrate moving and combining key data streams and delivering the data to the Namibia Department of Hydrology during their flood season which typically is January through April. In this pilot, a variety of moderate resolution and high resolution satellite flood imagery was rapidly delivered and used in conjunction with flood predictive models in Namibia. This was collected in conjunction with ground measurements and was used to examine how to create a customized flood early warning system. During the first year, the team made use of SensorWeb technology to gather various sensor data which was used to monitor flood waves traveling down basins originating in Angola, but eventually flooding villages in Namibia. The team made use of standardized interfaces such as those articulated under the Open Cloud Consortium (OGC) Sensor Web Enablement (SWE) set of web services was good [1][2]. However, it was discovered that in order to make a system like this functional, there were many performance issues. Data sets were large and located in a variety of location behind firewalls and had to be accessed across open networks, so security was an issue. Furthermore, the network access acted as bottleneck to transfer map products to where they are needed. Finally, during disasters, many users and computer processes act in parallel and thus it was very easy to overload the single string of computers stitched together in a virtual system that was initially developed. To address some of these performance issues, the team partnered with the Open Cloud Consortium (OCC) who supplied a Computation Cloud located at the University of Illinois at Chicago and some manpower to administer this Cloud. The Flood SensorWeb [3] system was interfaced to the Cloud to provide a high performance user interface and product development engine. Figure 1 shows the functional diagram of the Flood SensorWeb. Figure 2 shows some of the functionality of the Computation Cloud that was integrated. A significant portion of the original system was ported to the Cloud and during the past year, technical issues were resolved which included web access to the Cloud, security over the open Internet, beginning experiments on how to handle surge capacity by using the virtual machines in the cloud in parallel, using tiling techniques to render large data sets as layers on map, interfaces to allow user to customize the data processing/product chain and other performance enhancing techniques. The conclusion reached from the effort and this presentation is that defining the interoperability standards in a small fraction of the work. For example, once open web service standards were defined, many users could not make use of the standards due to security restrictions. Furthermore, once an interoperable sysm is functional, then a surge of users can render a system unusable, especially in the disaster domain.

A Method for Snow Reanalysis: The Sierra Nevada (USA) Example

NASA Technical Reports Server (NTRS)

Girotto, Manuela; Margulis, Steven; Cortes, Gonzalo; Durand, Michael

2017-01-01

This work presents a state-of-the art methodology for constructing snow water equivalent (SWE) reanalysis. The method is comprised of two main components: (1) a coupled land surface model and snow depletion curve model, which is used to generate an ensemble of predictions of SWE and snow cover area for a given set of (uncertain) inputs, and (2) a reanalysis step, which updates estimation variables to be consistent with the satellite observed depletion of the fractional snow cover time series. This method was applied over the Sierra Nevada (USA) based on the assimilation of remotely sensed fractional snow covered area data from the Landsat 5-8 record (1985-2016). The verified dataset (based on a comparison with over 9000 station years of in situ data) exhibited mean and root-mean-square errors less than 3 and 13 cm, respectively, and correlation greater than 0.95 compared with in situ SWE observations. The method (fully Bayesian), resolution (daily, 90-meter), temporal extent (31 years), and accuracy provide a unique dataset for investigating snow processes. This presentation illustrates how the reanalysis dataset was used to provide a basic accounting of the stored snowpack water in the Sierra Nevada over the last 31 years and ultimately improve real-time streamflow predictions.

The value of quantitative shear wave elastography in differentiating the cervical lymph nodes in patients with thyroid nodules.

PubMed

You, Jun; Chen, Juan; Xiang, Feixiang; Song, Yue; Khamis, Simai; Lu, Chengfa; Lv, Qing; Zhang, Yanrong; Xie, Mingxing

2018-04-01

This study aimed at evaluating the diagnostic performance of quantitative shear wave elastography (SWE) in differentiating metastatic cervical lymph nodes from benign nodes in patients with thyroid nodules. One hundred and forty-one cervical lymph nodes from 39 patients with thyroid nodules that were diagnosed as papillary thyroid cancer had been imaged with SWE. The shear elasticity modulus, which indicates the stiffness of the lymph nodes, was measured in terms of maximum shear elasticity modulus (maxSM), minimum shear elasticity modulus (minSM), mean shear elasticity modulus (meanSM), and standard deviation (SD) of the shear elasticity modulus. All the patients underwent thyroid surgery, 50 of the suspicious lymph nodes were resected, and 91 lymph nodes were followed up for 6 months. The maxSM value, minSM value, meanSM value, and SD value of the metastatic lymph nodes were significantly higher than those of the benign nodes. The area under the curve of the maxSM value, minSM value, meanSM value, and SD value were 0.918, 0.606, 0.865, and 0.915, respectively. SWE can differentiate metastasis from benign cervical lymph nodes in patients with thyroid nodules, and the maxSM, meanSM, and SD may be valuable quantitative indicators for characterizing cervical lymph nodes.

Children’s Relative Clause Markers in Two Nonmainstream Dialects of English

PubMed Central

Oetting, Janna B.; Newkirk, Brandi L.

2013-01-01

Purpose We examined children’s productions of mainstream and nonmainstream relative clause markers (e.g., that, who, which, what, where, Ø) in African American English (AAE) and Southern White English (SWE) as a function of three linguistic variables (syntactic role of the marker, humanness of the antecedent, and adjacency of the noun phrase head). Method The data were language samples from 99 typically developing four- to six-year-olds; 61 spoke AAE and 38 spoke SWE. Results The majority of the children’s relative clauses included mainstream markers. Nonmainstream markers were rare, with 3-6% involving Ø subjects and 2% involving what. The children produced who exclusively as subjects and with human antecedents, where exclusively as locatives and with nonhuman antecedents, and Ø and what primarily as direct objects or objects of prepositions and with nonhuman antecedents. Conclusions Although AAE- and SWE-speaking children produce some nonmainstream relative markers, the majority of their markers are mainstream. Their use of relative markers is also influenced by linguistic variables in ways that are consistent with a wide range of mainstream and nonmainstream English dialects. These findings show across-dialect similarity in children’s relative clauses, even though characterization of relative clauses as a contrastive dialect structure remains justified. PMID:21453062

Assimilation of Terrestrial Water Storage from GRACE in a Snow-Dominated Basin

NASA Technical Reports Server (NTRS)

Forman, Barton A.; Reichle, R. H.; Rodell, M.

2011-01-01

Terrestrial water storage (TWS) information derived from Gravity Recovery and Climate Experiment (GRACE) measurements is assimilated into a land surface model over the Mackenzie River basin located in northwest Canada. Assimilation is conducted using an ensemble Kalman smoother (EnKS). Model estimates with and without assimilation are compared against independent observational data sets of snow water equivalent (SWE) and runoff. For SWE, modest improvements in mean difference (MD) and root mean squared difference (RMSD) are achieved as a result of the assimilation. No significant differences in temporal correlations of SWE resulted. Runoff statistics of MD remain relatively unchanged while RMSD statistics, in general, are improved in most of the sub-basins. Temporal correlations are degraded within the most upstream sub-basin, but are, in general, improved at the downstream locations, which are more representative of an integrated basin response. GRACE assimilation using an EnKS offers improvements in hydrologic state/flux estimation, though comparisons with observed runoff would be enhanced by the use of river routing and lake storage routines within the prognostic land surface model. Further, GRACE hydrology products would benefit from the inclusion of better constrained models of post-glacial rebound, which significantly affects GRACE estimates of interannual hydrologic variability in the Mackenzie River basin.

Subcritical Water Technology for Enhanced Extraction of Biochemical Compounds from Chlorella vulgaris

PubMed Central

Awaluddin, S. A.; Thiruvenkadam, Selvakumar; Izhar, Shamsul; Hiroyuki, Yoshida; Danquah, Michael K.; Harun, Razif

2016-01-01

Subcritical water extraction (SWE) technology has been used for the extraction of active compounds from different biomass materials with low process cost, mild operating conditions, short process times, and environmental sustainability. With the limited application of the technology to microalgal biomass, this work investigates parametrically the potential of subcritical water for high-yield extraction of biochemicals such as carbohydrates and proteins from microalgal biomass. The SWE process was optimized using central composite design (CCD) under varying process conditions of temperature (180–374°C), extraction time (1–20 min), biomass particulate size (38–250 μm), and microalgal biomass loading (5–40 wt.%). Chlorella vulgaris used in this study shows high volatile matter (83.5 wt.%) and carbon content (47.11 wt.%), giving advantage as a feedstock for biofuel production. The results showed maximum total carbohydrate content and protein yields of 14.2 g/100 g and 31.2 g/100 g, respectively, achieved under the process conditions of 277°C, 5% of microalgal biomass loading, and 5 min extraction time. Statistical analysis revealed that, of all the parameters investigated, temperature is the most critical during SWE of microalgal biomass for protein and carbohydrate production. PMID:27366748

An experimental study: evaluating the tissue structure of penis with 2D-ShearWave™ Elastography.

PubMed

Qiao, X-H; Zhang, J-J; Gao, F; Li, F; Liu, Y; Xing, L-X; Du, L-F; Xing, J-F

2017-01-01

The aim of this study was to investigate the feasibility of two-dimensional-ShearWave™ Elastography (2D-SWE) on evaluating the change of tissue structure of penis. Twenty healthy male Sprague Dawley rats were divided into penis-developed group (PDG, 52 weeks) and penis-underdeveloped group (PUDG, 5 weeks). The ultrafast ultrasound device-Aixplorer® (SuperSonic Imagine) was used for 2D-SWE imaging of the penis, the measurement index was shear wave stiffness (SWS, kPa). All rat penises were cut off immediately after ultrasonic examination. After paraffin embedding, slicing and hematoxylin-eosin staining, the tissue structure of the penis was observed under light microscope. SWS of all rat penises were measured successfully. The results showed that SWS of PDG was significantly lower than PUDG (P=0.008). At the same time, the pathological results found that there were significant differences in the tissue structures (sinusoids, smooth muscle cells and fibrocytes) of the penises between the two groups. These results suggest that there are significant differences in SWS between different tissue structures of penis. 2D-SWE is expected to be used on the etiological diagnosis of erectile dysfunction by serving as a new noninvasive method of evaluating the change of tissue structure of penis.

Use of shear wave elastography to differentiate benign and malignant breast lesions.

PubMed

Çebi Olgun, Deniz; Korkmazer, Bora; Kılıç, Fahrettin; Dikici, Atilla Süleyman; Velidedeoğlu, Mehmet; Aydoğan, Fatih; Kantarcı, Fatih; Yılmaz, Mehmet Halit

2014-01-01

We aimed to determine the correlations between the elasticity values of solid breast masses and histopathological findings to define cutoff elasticity values differentiating malignant from benign lesions. A total of 115 solid breast lesions of 109 consecutive patients were evaluated prospectively using shear wave elastography (SWE). Two orthogonal elastographic images of each lesion were obtained. Minimum, mean, and maximum elasticity values were calculated in regions of interest placed over the stiffest areas on the two images; we also calculated mass/fat elasticity ratios. Correlation of elastographic measurements with histopathological results were studied. Eighty-three benign and thirty-two malignant lesions were histopathologically diagnosed. The minimum, mean, and maximum elasticity values, and the mass/fat elasticity ratios of malignant lesions, were significantly higher than those of benign lesions. The cutoff value was 45.7 kPa for mean elasticity (sensitivity, 96%; specificity, 95%), 54.3 kPa for maximum elasticity (sensitivity, 95%; specificity, 94%), 37.1 kPa for minimum elasticity (sensitivity, 96%; specificity, 95%), and 4.6 for the mass/fat elasticity ratio (sensitivity, 97%; specificity, 95%). SWE yields additional valuable quantitative data to ultrasonographic examination on solid breast lesions. SWE may serve as a complementary tool for diagnosis of breast lesions. Long-term clinical studies are required to accurately select lesions requiring biopsy.

Influence of region of interest size and ultrasound lesion size on the performance of 2D shear wave elastography (SWE) in solid breast masses.

PubMed

Skerl, K; Vinnicombe, S; Giannotti, E; Thomson, K; Evans, A

2015-12-01

To evaluate the influence of the region of interest (ROI) size and lesion diameter on the diagnostic performance of 2D shear wave elastography (SWE) of solid breast lesions. A study group of 206 consecutive patients (age range 21-92 years) with 210 solid breast lesions (70 benign, 140 malignant) who underwent core biopsy or surgical excision was evaluated. Lesions were divided into small (diameter <15 mm, n=112) and large lesions (diameter ≥15 mm, n=98). An ROI with a diameter of 1, 2, and 3 mm was positioned over the stiffest part of the lesion. The maximum elasticity (Emax), mean elasticity (Emean) and standard deviation (SD) for each ROI size were compared to the pathological outcome. Statistical analysis was undertaken using the chi-square test and receiver operating characteristic (ROC) analysis. The ROI size used has a significant impact on the performance of Emean and SD but not on Emax. Youden's indices show a correlation with the ROI size and lesion size: generally, the benign/malignant threshold is lower with increasing ROI size but higher with increasing lesion size. No single SWE parameter has superior performance. Lesion size and ROI size influence diagnostic performance. Copyright © 2015. Published by Elsevier Ltd.

Shear wave elastography of breast cancer: Sensitivity according to histological type in a large cohort.

PubMed

Evans, Andrew; Sim, Yee Ting; Thomson, Kim; Jordan, Lee; Purdie, Colin; Vinnicombe, Sarah J

2016-04-01

To define the shear wave elastography (SWE) characteristics of breast cancer histological types by size in a large cohort. Consecutive patients with US visible masses underwent SWE. All those with confirmed invasive breast cancer were included in the study. Histologic type was ascertained from core biopsy and surgical resection specimens. For each type, mean and median values for Emean and Emax were ascertained. Commoner tumour types were further analysed by invasive size. The significance of differences was established using the Chi-square test. 1137 tumours constituted the study group. The proportion of tumours with Emean below 50 kPa was higher in tubular cancers (23%) compared to ductal carcinomas of no specific type (DNST) (6%) (p < 0.001). Emax below 80 kPa was seen in 34% of tubular cancers compared to 16% of DNST (p < 0.002). Emean and Emax for lobular, mucinous, papillary and metaplastic cancers were not different from those of DNST. There were no significant differences in Emean or Emax between tumour types once broken down according to invasive size. Most breast cancer histological types have similar SWE characteristics. The exception is tubular cancer which has significantly lower stiffness than other histologic types, accounted for largely by their small size. Copyright © 2016 Elsevier Ltd. All rights reserved.

Unipept web services for metaproteomics analysis.

PubMed

Mesuere, Bart; Willems, Toon; Van der Jeugt, Felix; Devreese, Bart; Vandamme, Peter; Dawyndt, Peter

2016-06-01

Unipept is an open source web application that is designed for metaproteomics analysis with a focus on interactive datavisualization. It is underpinned by a fast index built from UniProtKB and the NCBI taxonomy that enables quick retrieval of all UniProt entries in which a given tryptic peptide occurs. Unipept version 2.4 introduced web services that provide programmatic access to the metaproteomics analysis features. This enables integration of Unipept functionality in custom applications and data processing pipelines. The web services are freely available at http://api.unipept.ugent.be and are open sourced under the MIT license. Unipept@ugent.be Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Interactive web-based learning modules prior to general medicine advanced pharmacy practice experiences.

PubMed

Isaacs, Alex N; Walton, Alison M; Nisly, Sarah A

2015-04-25

To implement and evaluate interactive web-based learning modules prior to advanced pharmacy practice experiences (APPEs) on inpatient general medicine. Three clinical web-based learning modules were developed for use prior to APPEs in 4 health care systems. The aim of the interactive modules was to strengthen baseline clinical knowledge before the APPE to enable the application of learned material through the delivery of patient care. For the primary endpoint, postassessment scores increased overall and for each individual module compared to preassessment scores. Postassessment scores were similar among the health care systems. The survey demonstrated positive student perceptions of this learning experience. Prior to inpatient general medicine APPEs, web-based learning enabled the standardization and assessment of baseline student knowledge across 4 health care systems.

Using Semantic Web Technologies for Cohort Identification from Electronic Health Records for Clinical Research

PubMed Central

Pathak, Jyotishman; Kiefer, Richard C.; Chute, Christopher G.

2012-01-01

The ability to conduct genome-wide association studies (GWAS) has enabled new exploration of how genetic variations contribute to health and disease etiology. One of the key requirements to perform GWAS is the identification of subject cohorts with accurate classification of disease phenotypes. In this work, we study how emerging Semantic Web technologies can be applied in conjunction with clinical data stored in electronic health records (EHRs) to accurately identify subjects with specific diseases for inclusion in cohort studies. In particular, we demonstrate the role of using Resource Description Framework (RDF) for representing EHR data and enabling federated querying and inferencing via standardized Web protocols for identifying subjects with Diabetes Mellitus. Our study highlights the potential of using Web-scale data federation approaches to execute complex queries. PMID:22779040

Model My Watershed and BiG CZ Data Portal: Interactive geospatial analysis and hydrological modeling web applications that leverage the Amazon cloud for scientists, resource managers and students

NASA Astrophysics Data System (ADS)

Aufdenkampe, A. K.; Mayorga, E.; Tarboton, D. G.; Sazib, N. S.; Horsburgh, J. S.; Cheetham, R.

2016-12-01

The Model My Watershed Web app (http://wikiwatershed.org/model/) was designed to enable citizens, conservation practitioners, municipal decision-makers, educators, and students to interactively select any area of interest anywhere in the continental USA to: (1) analyze real land use and soil data for that area; (2) model stormwater runoff and water-quality outcomes; and (3) compare how different conservation or development scenarios could modify runoff and water quality. The BiG CZ Data Portal is a web application for scientists for intuitive, high-performance map-based discovery, visualization, access and publication of diverse earth and environmental science data via a map-based interface that simultaneously performs geospatial analysis of selected GIS and satellite raster data for a selected area of interest. The two web applications share a common codebase (https://github.com/WikiWatershed and https://github.com/big-cz), high performance geospatial analysis engine (http://geotrellis.io/ and https://github.com/geotrellis) and deployment on the Amazon Web Services (AWS) cloud cyberinfrastructure. Users can use "on-the-fly" rapid watershed delineation over the national elevation model to select their watershed or catchment of interest. The two web applications also share the goal of enabling the scientists, resource managers and students alike to share data, analyses and model results. We will present these functioning web applications and their potential to substantially lower the bar for studying and understanding our water resources. We will also present work in progress, including a prototype system for enabling citizen-scientists to register open-source sensor stations (http://envirodiy.org/mayfly/) to stream data into these systems, so that they can be reshared using Water One Flow web services.

MODIS Snowcover in North America: A Comparison of Winter 2013/14 and 2014/15 to Median Condition

NASA Astrophysics Data System (ADS)

Trubilowicz, J. W.; Floyd, B. C.; D'Amore, D. V.; Bidlack, A.

2015-12-01

The winters from 2013-2015 had exceptionally low snow-packs in much of western North America. In particular, the winter of 2014/2015 had the lowest peak snow-water-equivalent (SWE) depths ever recorded in many areas of the Pacific Northwest. These low snow-packs have contributed to drought conditions from British Columbia to California. Along with the low SWE values, the snow covered area (SCA) of the previous two winters has been a significant departure from normal conditions. SCA is related to SWE, rain-on-snow events and the seasonal water supply, provides insulation for plant root systems from late season frost, and is an important factor in forest fire hazard, delaying the start of soil and fuel drying. Remote sensing can be a useful tool to monitor SCA over large regions, with the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments providing a suitable temporal (twice daily), and spatial resolution (500m) to create detailed maps, even with high frequencies of cloud covered days. While comparison of SWE at snow monitoring sites to historical values is a standard analysis, doing the same for SCA has been difficult due to the technical and logistical problems related to processing the large amounts of spatial data required to determine a 'normal' annual SCA cycle. Through the use of new cloud-based computation methods from Google Earth Engine, we have calculated the monthly median (from 2002-2015) MODIS SCA, at a 500 m resolution, for all of the major Pacific draining watersheds of North America. Determining the 'normal' SCA cycle of the past 13 years allowed us to compare the past two winters to the median SCA levels, showing which basins have seen the most significant departures from normal SCA levels. Results indicate more significant departures from normal in basins with significant maritime-influenced snow-packs.

Quantifying the variability of snowpack properties and processes in a small-forested catchment representative of the boreal zone

NASA Astrophysics Data System (ADS)

Parajuli, A.; Nadeau, D.; Anctil, F.; Parent, A. C.; Bouchard, B.; Jutras, S.

2017-12-01

In snow-fed catchments, it is crucial to monitor and to model snow water equivalent (SWE), particularly to simulate the melt water runoff. However, the distribution of SWE can be highly heterogeneous, particularly within forested environments, mainly because of the large variability in snow depths. Although the boreal forest is the dominant land cover in Canada and in a few other northern countries, very few studies have quantified the spatiotemporal variability of snow depths and snowpack dynamics within this biome. The objective of this paper is to fill this research gap, through a detailed monitoring of snowpack dynamics at nine locations within a 3.57 km2 experimental forested catchment in southern Quebec, Canada (47°N, 71°W). The catchment receives 6 m of snow annually on average and is predominantly covered with balsam fir stand with some traces of spruce and white birch. In this study, we used a network of nine so-called `snow profiling stations', providing automated snow depth and snowpack temperature profile measurements, as well as three contrasting sites (juvenile, sapling and open areas) where sublimation rates were directly measured with flux towers. In addition, a total of 1401 manual snow samples supported by 20 snow pits measurements were collected throughout the winter of 2017. This paper presents some preliminary analyses of this unique dataset. Simple empirical relations relying SWE with easy-to-determine proxies, such as snow depths and snow temperature, are tested. Then, binary regression trees and multiple regression analysis are used to model SWE using topographic characteristics (slope, aspect, elevation), forest features (tree height, tree diameter, forest density and gap fraction) and meteorological forcing (solar radiation, wind speed, snow-pack temperature profile, air temperature, humidity). An analysis of sublimation rates comparing open area, saplings and juvenile forest is also presented in this paper.

Variable-Resolution Ensemble Climatology Modeling of Sierra Nevada Snowpack within the Community Earth System Model (CESM)

NASA Astrophysics Data System (ADS)

Rhoades, A.; Ullrich, P. A.; Zarzycki, C. M.; Levy, M.; Taylor, M.

2014-12-01

Snowpack is crucial for the western USA, providing around 75% of the total fresh water supply (Cayan et al., 1996) and buffering against seasonal aridity impacts on agricultural, ecosystem, and urban water demands. The resilience of the California water system is largely dependent on natural stores provided by snowpack. This resilience has shown vulnerabilities due to anthropogenic global climate change. Historically, the northern Sierras showed a net decline of 50-75% in snow water equivalent (SWE) while the southern Sierras showed a net accumulation of 30% (Mote et al., 2005). Future trends of SWE highlight that western USA SWE may decline by 40-70% (Pierce and Cayan, 2013), snowfall may decrease by 25-40% (Pierce and Cayan, 2013), and more winter storms may tend towards rain rather than snow (Bales et al., 2006). The volatility of Sierran snowpack presents a need for scientific tools to help water managers and policy makers assess current and future trends. A burgeoning tool to analyze these trends comes in the form of variable-resolution global climate modeling (VRGCM). VRGCMs serve as a bridge between regional and global models and provide added resolution in areas of need, eliminate lateral boundary forcings, provide model runtime speed up, and utilize a common dynamical core, physics scheme and sub-grid scale parameterization package. A cubed-sphere variable-resolution grid with 25 km horizontal resolution over the western USA was developed for use in the Community Atmosphere Model (CAM) within the Community Earth System Model (CESM). A 25-year three-member ensemble climatology (1980-2005) is presented and major snowpack metrics such as SWE, snow depth, snow cover, and two-meter surface temperature are assessed. The ensemble simulation is also compared to observational, reanalysis, and WRF model datasets. The variable-resolution model provides a mechanism for reaching towards non-hydrostatic scales and simulations are currently being developed with refined nests of 12.5km resolution over California.

Bark Beetles Modify the Impact of Snow Drought on Remotely Sensed Forest Productivity in the Southern Rocky Mountains, USA

NASA Astrophysics Data System (ADS)

Knowles, J. F.; Lestak, L.; Molotch, N. P.

2016-12-01

We evaluated the long term (1989-2012) relationship between the satellite-observed Normalized Difference Vegetation Index (NDVI), snowpack accumulation, and atmospheric demand throughout the Southern Rocky Mountain Ecoregion, USA. Deviations from this relationship were further explored during pre- and post-disturbance conditions associated with bark beetles and drought. Over the entire study area, both the snow water equivalent (SWE) and a snow aridity index (SAI), which used the SWE to normalize potential evapotranspiration (PET), were significant predictors of the long-term AVHRR NDVI, but the SAI was a better predictor of NDVI relative to SWE regardless of disturbance. Since these relationships were weaker in disturbed areas, we also introduced a metric of tree mortality, and subsequent multiple linear regression of SAI and cumulative mortality best predicted the NDVI from a pair of heavily impacted focus areas within the larger study area. The post-disturbance NDVI was systematically reduced per unit SAI in these areas, and the difference between the observed and predicted (from pre-disturbance regressions) post-disturbance NDVI was significantly correlated with the cumulative forest mortality. At the Ecoregion scale, these disturbance effects were not clearly evident, and we attribute this to spatial variability of both SAI and NDVI throughout the large study area as evidenced by spatial analysis of Moderate Resolution Imaging Spectroradiometer (MODIS)-derived data. These results constrain the expected reduction in forest productivity due to disturbance and demonstrate that this reduction can be particularly evident during drought conditions resultant from low snow accumulation during the winter. Hence, terrestrial carbon uptake may decrease non-linearly post disturbance. This work has implications for predicting the ecohydrological response to climate change in the southern Rocky Mountains, as reductions in SWE and increases in PET are predicted for this area in the future, and therefore changes in the terrestrial carbon, water, and energy cycles should be expected.

Shear-wave elastography for breast masses: local shear wave speed (m/sec) versus Young modulus (kPa).

PubMed

Youk, Ji Hyun; Son, Eun Ju; Park, Ah Young; Kim, Jeong-Ah

2014-01-01

To evaluate and compare the performance of shear-wave elastography (SWE) for breast masses using the local shear wave speed (m/sec) vs. Young modulus (kPa). A total of 130 breast lesions in 123 women who underwent SWE before ultrasound- guided core needle biopsy or surgical excision were included. With the region-of-interest placed over the stiffest areas of the lesion on SWE, the quantitative mean, maximum, and standard deviation (SD) of the elasticity values were measured in kPa and m/sec for each lesion. The SD was also measured with the region-of-interest including the whole breast lesion (wSD). The area under the receiver operating characteristic curve (AUC), sensitivity, and specificity of each elasticity value measured in kPa and m/sec were compared. Of the 130 lesions, 49 (37.7%) were malignant and 81 (62.3%) were benign. The AUCs for the mean, maximum, and SD of the elasticity values using kPa and m/sec did not differ significantly: mean, 0.974 vs. 0.974; maximum, 0.960 vs. 0.976; SD, 0.916 vs. 0.916. However, the AUC for wSD showed a significant difference: 0.964 (kPa) vs. 0.960 (m/sec) (P=0.036). There was no significant difference in the sensitivity and specificity of the mean, maximum, and wSD of the elasticity values. However, the specificity of the SD was significantly different between the two different measurements: 95.1% (kPa) vs. 87.7% (m/sec) (P=0.031). The quantitative elasticity values measured in kPa and m/sec on SWE showed good diagnostic performance. The specificity of the SD and AUC of the wSD measured in kPa were significantly higher than those measured in m/sec.

Lesion stiffness measured by shear-wave elastography: Preoperative predictor of the histologic underestimation of US-guided core needle breast biopsy.

PubMed

Park, Ah Young; Son, Eun Ju; Kim, Jeong-Ah; Han, Kyunghwa; Youk, Ji Hyun

2015-12-01

To determine whether lesion stiffness measured by shear-wave elastography (SWE) can be used to predict the histologic underestimation of ultrasound (US)-guided 14-gauge core needle biopsy (CNB) for breast masses. This retrospective study enrolled 99 breast masses from 93 patients, including 40 high-risk lesions and 59 ductal carcinoma in situ (DCIS), which were diagnosed by US-guided 14-gauge CNB. SWE was performed for all breast masses to measure quantitative elasticity values before US-guided CNB. To identify the preoperative factors associated with histologic underestimation, patients' age, symptoms, lesion size, B-mode US findings, and quantitative SWE parameters were compared according to the histologic upgrade after surgery using the chi-square test, Fisher's exact test, or independent t-test. The independent factors for predicting histologic upgrade were evaluated using multivariate logistic regression analysis. The underestimation rate was 28.3% (28/99) in total, 25.0% (10/40) in high-risk lesions, and 30.5% (18/59) in DCIS. All elasticity values of the upgrade group were significantly higher than those of the non-upgrade group (P<0.001). On multivariate analysis, the mean (Odds ratio [OR]=1.021, P=0.001), maximum (OR=1.015, P=0.008), and minimum (OR=1.028, P=0.001) elasticity values were independently associated with histologic underestimation. The patients' age, lesion size, and final assessment category on US of the upgrade group were higher than those of the non-upgrade group (P=0.046 for age; P=0.021 for lesion size; P=0.030 for US category), but these were not independent predictors of histologic underestimation on multivariate analysis. Breast lesion stiffness quantitatively measured by SWE could be helpful to predict the underestimation of malignancy in US-guided 14-gauge CNB. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

The shifting nature of vegetation controls on peak snowpack with varying slope and aspect

NASA Astrophysics Data System (ADS)

Biederman, J. A.; Harpold, A. A.; Broxton, P. D.; Brooks, P. D.

2012-12-01

The controls on peak seasonal snowpack are known to shift between forested and open environments as well as with slope and aspect. Peak snowpack is predicted well by interception models under uniformly dense canopy, while topography, wind and radiation are strong predictors in open areas. However, many basins have complex mosaics of forest canopy and small gaps, where snowpack controls involve complex interactions among climate, topography and forest structure. In this presentation we use a new fully distributed tree-scale model to investigate vegetation controls on snowpack for a range of slope and aspect, and we evaluate the energy balance in forest canopy and gap environments. The model is informed by airborne LiDAR and ground-based observations of climate, vegetation and snowpack. It represents interception, snow distribution by wind, latent and sensible heat fluxes, and radiative fluxes above and below the canopy at a grid scale of 1 m square on an hourly time step. First, the model is minimally calibrated using continuous records of snow depth and snow water equivalent (SWE). Next, the model is evaluated using distributed observations at peak accumulation. Finally, the domain is synthetically altered to introduce ranges of slope and aspect. Northerly aspects accumulate greater peak SWE than southerly aspects (e.g. 275 mm vs. 250 mm at a slope of 28 %) but show lower spatial variability (e. g. CV = 0.14 vs. CV = 0.17 at slope of 28 %). On northerly aspects, most of the snowpack remains shaded by vegetation, whereas on southerly aspects the northern portions of gaps and southern forest edges receive direct insolation during late winter. This difference in net radiation makes peak SWE in forest gaps and adjacent forest edges more sensitive to topography than SWE in areas under dense canopy. Tree-scale modeling of snow dynamics over synthetic terrain offers extensive possibilities to test interactions among vegetation and topographic controls.

Web-based interactive visualization in a Grid-enabled neuroimaging application using HTML5.

PubMed

Siewert, René; Specovius, Svenja; Wu, Jie; Krefting, Dagmar

2012-01-01

Interactive visualization and correction of intermediate results are required in many medical image analysis pipelines. To allow certain interaction in the remote execution of compute- and data-intensive applications, new features of HTML5 are used. They allow for transparent integration of user interaction into Grid- or Cloud-enabled scientific workflows. Both 2D and 3D visualization and data manipulation can be performed through a scientific gateway without the need to install specific software or web browser plugins. The possibilities of web-based visualization are presented along the FreeSurfer-pipeline, a popular compute- and data-intensive software tool for quantitative neuroimaging.

Sensor Web Interoperability Testbed Results Incorporating Earth Observation Satellites

NASA Technical Reports Server (NTRS)

Frye, Stuart; Mandl, Daniel J.; Alameh, Nadine; Bambacus, Myra; Cappelaere, Pat; Falke, Stefan; Derezinski, Linda; Zhao, Piesheng

2007-01-01

This paper describes an Earth Observation Sensor Web scenario based on the Open Geospatial Consortium s Sensor Web Enablement and Web Services interoperability standards. The scenario demonstrates the application of standards in describing, discovering, accessing and tasking satellites and groundbased sensor installations in a sequence of analysis activities that deliver information required by decision makers in response to national, regional or local emergencies.

KnowledgePuzzle: A Browsing Tool to Adapt the Web Navigation Process to the Learner's Mental Model

ERIC Educational Resources Information Center

AlAgha, Iyad

2012-01-01

This article presents KnowledgePuzzle, a browsing tool for knowledge construction from the web. It aims to adapt the structure of web content to the learner's information needs regardless of how the web content is originally delivered. Learners are provided with a meta-cognitive space (e.g., a concept mapping tool) that enables them to plan…

Potential for Monitoring Snow Cover in Boreal Forests by Combining MODIS Snow Cover and AMSR-E SWE Maps

NASA Technical Reports Server (NTRS)

Riggs, George A.; Hall, Dorothy K.; Foster, James L.

2009-01-01

Monitoring of snow cover extent and snow water equivalent (SWE) in boreal forests is important for determining the amount of potential runoff and beginning date of snowmelt. The great expanse of the boreal forest necessitates the use of satellite measurements to monitor snow cover. Snow cover in the boreal forest can be mapped with either the Moderate Resolution Imaging Spectroradiometer (MODIS) or the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) microwave instrument. The extent of snow cover is estimated from the MODIS data and SWE is estimated from the AMSR-E. Environmental limitations affect both sensors in different ways to limit their ability to detect snow in some situations. Forest density, snow wetness, and snow depth are factors that limit the effectiveness of both sensors for snow detection. Cloud cover is a significant hindrance to monitoring snow cover extent Using MODIS but is not a hindrance to the use of the AMSR-E. These limitations could be mitigated by combining MODIS and AMSR-E data to allow for improved interpretation of snow cover extent and SWE on a daily basis and provide temporal continuity of snow mapping across the boreal forest regions in Canada. The purpose of this study is to investigate if temporal monitoring of snow cover using a combination of MODIS and AMSR-E data could yield a better interpretation of changing snow cover conditions. The MODIS snow mapping algorithm is based on snow detection using the Normalized Difference Snow Index (NDSI) and the Normalized Difference Vegetation Index (NDVI) to enhance snow detection in dense vegetation. (Other spectral threshold tests are also used to map snow using MODIS.) Snow cover under a forest canopy may have an effect on the NDVI thus we use the NDVI in snow detection. A MODIS snow fraction product is also generated but not used in this study. In this study the NDSI and NDVI components of the snow mapping algorithm were calculated and analyzed to determine how they changed through the seasons. A blended snow product, the Air Force Weather Agency and NASA (ANSA) snow algorithm and product has recently been developed. The ANSA algorithm blends the MODIS snow cover and AMSR-E SWE products into a single snow product that has been shown to improve the performance of snow cover mapping. In this study components of the ANSA snow algorithm are used along with additional MODIS data to monitor daily changes in snow cover over the period of 1 February to 30 June 2008.

Database Organisation in a Web-Enabled Free and Open-Source Software (foss) Environment for Spatio-Temporal Landslide Modelling

NASA Astrophysics Data System (ADS)

Das, I.; Oberai, K.; Sarathi Roy, P.

2012-07-01

Landslides exhibit themselves in different mass movement processes and are considered among the most complex natural hazards occurring on the earth surface. Making landslide database available online via WWW (World Wide Web) promotes the spreading and reaching out of the landslide information to all the stakeholders. The aim of this research is to present a comprehensive database for generating landslide hazard scenario with the help of available historic records of landslides and geo-environmental factors and make them available over the Web using geospatial Free & Open Source Software (FOSS). FOSS reduces the cost of the project drastically as proprietary software's are very costly. Landslide data generated for the period 1982 to 2009 were compiled along the national highway road corridor in Indian Himalayas. All the geo-environmental datasets along with the landslide susceptibility map were served through WEBGIS client interface. Open source University of Minnesota (UMN) mapserver was used as GIS server software for developing web enabled landslide geospatial database. PHP/Mapscript server-side application serve as a front-end application and PostgreSQL with PostGIS extension serve as a backend application for the web enabled landslide spatio-temporal databases. This dynamic virtual visualization process through a web platform brings an insight into the understanding of the landslides and the resulting damage closer to the affected people and user community. The landslide susceptibility dataset is also made available as an Open Geospatial Consortium (OGC) Web Feature Service (WFS) which can be accessed through any OGC compliant open source or proprietary GIS Software.

Exploratory Visual Analytics of a Dynamically Built Network of Nodes in a WebGL-Enabled Browser

DTIC Science & Technology

2014-01-01

dimensionality reduction, feature extraction, high-dimensional data, t-distributed stochastic neighbor embedding, neighbor retrieval visualizer, visual...WebGL-enabled rendering is supported natively by browsers such as the latest Mozilla Firefox , Google Chrome, and Microsoft Internet Explorer 11. At the...appropriate names. The resultant 26-node network is displayed in a Mozilla Firefox browser in figure 2 (also see appendix B). 3 Figure 1. The

Examining Long-Term Global Climate Change on the Web.

ERIC Educational Resources Information Center

Huntoon, Jacqueline E.; Ridky, Robert K.

2002-01-01

Describes a web-based, inquiry-oriented activity that enables students to examine long-term global climate change. Supports instruction in other topics such as population growth. (Contains 34 references.) (DDR)

BioPortal: enhanced functionality via new Web services from the National Center for Biomedical Ontology to access and use ontologies in software applications.

PubMed

Whetzel, Patricia L; Noy, Natalya F; Shah, Nigam H; Alexander, Paul R; Nyulas, Csongor; Tudorache, Tania; Musen, Mark A

2011-07-01

The National Center for Biomedical Ontology (NCBO) is one of the National Centers for Biomedical Computing funded under the NIH Roadmap Initiative. Contributing to the national computing infrastructure, NCBO has developed BioPortal, a web portal that provides access to a library of biomedical ontologies and terminologies (http://bioportal.bioontology.org) via the NCBO Web services. BioPortal enables community participation in the evaluation and evolution of ontology content by providing features to add mappings between terms, to add comments linked to specific ontology terms and to provide ontology reviews. The NCBO Web services (http://www.bioontology.org/wiki/index.php/NCBO_REST_services) enable this functionality and provide a uniform mechanism to access ontologies from a variety of knowledge representation formats, such as Web Ontology Language (OWL) and Open Biological and Biomedical Ontologies (OBO) format. The Web services provide multi-layered access to the ontology content, from getting all terms in an ontology to retrieving metadata about a term. Users can easily incorporate the NCBO Web services into software applications to generate semantically aware applications and to facilitate structured data collection.

A Web 2.0-Based Collaborative Model for Multicultural Education

ERIC Educational Resources Information Center

Hossain, Md. Mokter; Aydin, Hasan

2011-01-01

Purpose: Web 2.0 is a collaborative web development platform that has had tremendous usage in building effective, interactive, and collaborative virtual societies at home and abroad. Multicultural study is another trend that has tremendous possibilities to help people in the fight against racism and enables them to become active members of a…

Web 2.0 in the Mathematics Classroom

ERIC Educational Resources Information Center

McCoy, Leah P.

2014-01-01

A key characteristic of successful mathematics teachers is that they are able to provide varied activities that promote student learning and assessment. Web 2.0 applications can provide an assortment of tools to help produce creative activities. A Web 2.0 tool enables the student to enter data and create multimedia products using text, graphics,…

Change Management Meets Web 2.0

ERIC Educational Resources Information Center

Gale, Doug

2008-01-01

Web 2.0 is the term used to describe a group of web-based creativity, information-sharing, and collaboration tools including wikis, blogs, social networks, and folksonomies. The common thread in all of these tools is twofold: They enable collaboration and information sharing, and their impact on higher education has been dramatic. A recent study…

Vermont hospital's web site focuses on valuable healthcare information.

PubMed

Rees, Tom

2005-01-01

Brattleboro Memorial Hospital's web site celebrates a century of caring in the region of Brattleboro, Vt. The web site, bmhvt.org, is loaded with information, including a local links page that enables site visitors to hook up with the Brattleboro Chamber of Commerce, the Area Health Education Council, Lifeline Personal Response Service, and more.

A Web Service and Interface for Remote Electronic Device Characterization

ERIC Educational Resources Information Center

Dutta, S.; Prakash, S.; Estrada, D.; Pop, E.

2011-01-01

A lightweight Web Service and a Web site interface have been developed, which enable remote measurements of electronic devices as a "virtual laboratory" for undergraduate engineering classes. Using standard browsers without additional plugins (such as Internet Explorer, Firefox, or even Safari on an iPhone), remote users can control a Keithley…

Server-Side Includes Made Simple.

ERIC Educational Resources Information Center

Fagan, Jody Condit

2002-01-01

Describes server-side include (SSI) codes which allow Webmasters to insert content into Web pages without programming knowledge. Explains how to enable the codes on a Web server, provides a step-by-step process for implementing them, discusses tags and syntax errors, and includes examples of their use on the Web site for Southern Illinois…

Web-based remote sensing of building energy performance

NASA Astrophysics Data System (ADS)

Martin, William; Nassiopoulos, Alexandre; Le Cam, Vincent; Kuate, Raphaël; Bourquin, Frédéric

2013-04-01

The present paper describes the design and the deployment of an instrumentation system enabling the energy monitoring of a building in a smart-grid context. The system is based on a network of wireless low power IPv6 sensors. Ambient temperature and electrical power for heating are measured. The management, storage, visualisation and treatment of the data is done through a web-based application that can be deployed as an online web service. The same web-based framework enables the acquisition of distant measured data such as those coming from a nearby weather station. On-site sensor and weather station data are then adequately treated based on inverse identification methods. The algorithms aim at determining the parameters of a numerical model suitable for a short-time horizon prediction of indoor climate. The model is based on standard multi-zone modelling assumptions and takes into account solar, airflow and conductive transfers. It was specially designed to render accurately inertia effects that are used in a demand-response strategy. All the hardware or software technologies that are used in the system are open and low cost so that they comply with the constraints of on-site deployment in buildings. The measured data as well as the model predictions can be accessed ubiquously through the web. This feature enables to consider a wide range of energy management applications at the disctrict, city or national level. The entire system has been deployed and tested in an experimental office building in Angers, France. It demonstrates the potential of ICT technologies to enable remotely controlled monitoring and surveillance in real time.

Cassini Archive Tracking System

NASA Technical Reports Server (NTRS)

Conner, Diane; Sayfi, Elias; Tinio, Adrian

2006-01-01

The Cassini Archive Tracking System (CATS) is a computer program that enables tracking of scientific data transfers from originators to the Planetary Data System (PDS) archives. Without CATS, there is no systematic means of locating products in the archive process or ensuring their completeness. By keeping a database of transfer communications and status, CATS enables the Cassini Project and the PDS to efficiently and accurately report on archive status. More importantly, problem areas are easily identified through customized reports that can be generated on the fly from any Web-enabled computer. A Web-browser interface and clearly defined authorization scheme provide safe distributed access to the system, where users can perform functions such as create customized reports, record a transfer, and respond to a transfer. CATS ensures that Cassini provides complete science archives to the PDS on schedule and that those archives are available to the science community by the PDS. The three-tier architecture is loosely coupled and designed for simple adaptation to multimission use. Written in the Java programming language, it is portable and can be run on any Java-enabled Web server.

The emerging Web 2.0 social software: an enabling suite of sociable technologies in health and health care education.

PubMed

Kamel Boulos, Maged N; Wheeler, Steve

2007-03-01

Web 2.0 sociable technologies and social software are presented as enablers in health and health care, for organizations, clinicians, patients and laypersons. They include social networking services, collaborative filtering, social bookmarking, folksonomies, social search engines, file sharing and tagging, mashups, instant messaging, and online multi-player games. The more popular Web 2.0 applications in education, namely wikis, blogs and podcasts, are but the tip of the social software iceberg. Web 2.0 technologies represent a quite revolutionary way of managing and repurposing/remixing online information and knowledge repositories, including clinical and research information, in comparison with the traditional Web 1.0 model. The paper also offers a glimpse of future software, touching on Web 3.0 (the Semantic Web) and how it could be combined with Web 2.0 to produce the ultimate architecture of participation. Although the tools presented in this review look very promising and potentially fit for purpose in many health care applications and scenarios, careful thinking, testing and evaluation research are still needed in order to establish 'best practice models' for leveraging these emerging technologies to boost our teaching and learning productivity, foster stronger 'communities of practice', and support continuing medical education/professional development (CME/CPD) and patient education.

Simple Web-based interactive key development software (WEBiKEY) and an example key for Kuruna (Poaceae: Bambusoideae)1

PubMed Central

Attigala, Lakshmi; De Silva, Nuwan I.; Clark, Lynn G.

2016-01-01

Premise of the study: Programs that are user-friendly and freely available for developing Web-based interactive keys are scarce and most of the well-structured applications are relatively expensive. WEBiKEY was developed to enable researchers to easily develop their own Web-based interactive keys with fewer resources. Methods and Results: A Web-based multiaccess identification tool (WEBiKEY) was developed that uses freely available Microsoft ASP.NET technologies and an SQL Server database for Windows-based hosting environments. WEBiKEY was tested for its usability with a sample data set, the temperate woody bamboo genus Kuruna (Poaceae). Conclusions: WEBiKEY is freely available to the public and can be used to develop Web-based interactive keys for any group of species. The interactive key we developed for Kuruna using WEBiKEY enables users to visually inspect characteristics of Kuruna and identify an unknown specimen as one of seven possible species in the genus. PMID:27144109

Nessi: An EEG-Controlled Web Browser for Severely Paralyzed Patients

PubMed Central

Bensch, Michael; Karim, Ahmed A.; Mellinger, Jürgen; Hinterberger, Thilo; Tangermann, Michael; Bogdan, Martin; Rosenstiel, Wolfgang; Birbaumer, Niels

2007-01-01

We have previously demonstrated that an EEG-controlled web browser based on self-regulation of slow cortical potentials (SCPs) enables severely paralyzed patients to browse the internet independently of any voluntary muscle control. However, this system had several shortcomings, among them that patients could only browse within a limited number of web pages and had to select links from an alphabetical list, causing problems if the link names were identical or if they were unknown to the user (as in graphical links). Here we describe a new EEG-controlled web browser, called Nessi, which overcomes these shortcomings. In Nessi, the open source browser, Mozilla, was extended by graphical in-place markers, whereby different brain responses correspond to different frame colors placed around selectable items, enabling the user to select any link on a web page. Besides links, other interactive elements are accessible to the user, such as e-mail and virtual keyboards, opening up a wide range of hypertext-based applications. PMID:18350132

A Security Architecture for Grid-enabling OGC Web Services

NASA Astrophysics Data System (ADS)

Angelini, Valerio; Petronzio, Luca

2010-05-01

In the proposed presentation we describe an architectural solution for enabling a secure access to Grids and possibly other large scale on-demand processing infrastructures through OGC (Open Geospatial Consortium) Web Services (OWS). This work has been carried out in the context of the security thread of the G-OWS Working Group. G-OWS (gLite enablement of OGC Web Services) is an international open initiative started in 2008 by the European CYCLOPS , GENESI-DR, and DORII Project Consortia in order to collect/coordinate experiences in the enablement of OWS's on top of the gLite Grid middleware. G-OWS investigates the problem of the development of Spatial Data and Information Infrastructures (SDI and SII) based on the Grid/Cloud capacity in order to enable Earth Science applications and tools. Concerning security issues, the integration of OWS compliant infrastructures and gLite Grids needs to address relevant challenges, due to their respective design principles. In fact OWS's are part of a Web based architecture that demands security aspects to other specifications, whereas the gLite middleware implements the Grid paradigm with a strong security model (the gLite Grid Security Infrastructure: GSI). In our work we propose a Security Architectural Framework allowing the seamless use of Grid-enabled OGC Web Services through the federation of existing security systems (mostly web based) with the gLite GSI. This is made possible mediating between different security realms, whose mutual trust is established in advance during the deployment of the system itself. Our architecture is composed of three different security tiers: the user's security system, a specific G-OWS security system, and the gLite Grid Security Infrastructure. Applying the separation-of-concerns principle, each of these tiers is responsible for controlling the access to a well-defined resource set, respectively: the user's organization resources, the geospatial resources and services, and the Grid resources. While the gLite middleware is tied to a consolidated security approach based on X.509 certificates, our system is able to support different kinds of user's security infrastructures. Our central component, the G-OWS Security Framework, is based on the OASIS WS-Trust specifications and on the OGC GeoRM architectural framework. This allows to satisfy advanced requirements such as the enforcement of specific geospatial policies and complex secure web service chained requests. The typical use case is represented by a scientist belonging to a given organization who issues a request to a G-OWS Grid-enabled Web Service. The system initially asks the user to authenticate to his/her organization's security system and, after verification of the user's security credentials, it translates the user's digital identity into a G-OWS identity. This identity is linked to a set of attributes describing the user's access rights to the G-OWS services and resources. Inside the G-OWS Security system, access restrictions are applied making use of the enhanced Geospatial capabilities specified by the OGC GeoXACML. If the required action needs to make use of the Grid environment the system checks if the user is entitled to access a Grid infrastructure. In that case his/her identity is translated to a temporary Grid security token using the Short Lived Credential Services (IGTF Standard). In our case, for the specific gLite Grid infrastructure, some information (VOMS Attributes) is plugged into the Grid Security Token to grant the access to the user's Virtual Organization Grid resources. The resulting token is used to submit the request to the Grid and also by the various gLite middleware elements to verify the user's grants. Basing on the presented framework, the G-OWS Security Working Group developed a prototype, enabling the execution of OGC Web Services on the EGEE Production Grid through the federation with a Shibboleth based security infrastructure. Future plans aim to integrate other Web authentication services such as OpenID, Kerberos and WS-Federation.

Non-contact measurements of ultrasonic waves on paper webs using a photorefractive interferometer

DOEpatents

Brodeur, Pierre H.; Lafond, Emmanuel F.

2000-01-01

An apparatus and method for non-contact measurement of ultrasonic waves on moving paper webs employs a photorefractive interferometer. The photorefractive interferometer employs an optical head in which the incident beam and reflected beam are coaxial, thus enabling detection of both in-plane and out-of-plane waves with a single apparatus. The incident beam and reference beams are focused into a line enabling greater power to be used without damaging the paper.

The behavior of the microwave emission of a conifer canopy during the fall-winter in Sodankylä, Finland

NASA Astrophysics Data System (ADS)

Li, Q.; Kelly, R. E. J.; Lemmetyinen, J.; Kontu, A.

2017-12-01

Spaceborne passive microwave (PM) systems are an important tool for estimating snow water equivalent (SWE) or snow depth (SD) in winter landscapes. However, because spaceborne radiometer footprints have a coarse spatial resolution, the measured upwelling brightness temperature (Tb) typically is a mixed signal propagated from multiple sources. Tree canopies can effectively attenuate microwave emission from the sub-canopy terrain beneath and can also have a strong emission signal. Therefore, these two combined observed processes decrease the sensitivity of the observed signal to SWE or SD. To evaluate the detailed behavior of the microwave emission from a forest landscape, the experiment focused on snow and vegetation radiative transfer processes was conducted at an established field site operated by the Finnish Meteorological Institute's Arctic Research Station in Sodankylä, Finland. In this experiment, downwelling Tbs from a target tree (Scots pine) was measured by an multi-frequency, dual polarization radiometer from Septermber 2016 to March 2017. A dendrometer and thermistor installed on the tree trunk at the height of 2 meters and 4 meters measured the sap flow and skin temperature of the tree. An adjacent weather station measured the air temperature. Snow cover conditions of the canopy was determined by an assessment web camera image time series. The three main findings are that first, the emissivity was positively correlated with tree skin temperatures below 0°C, but not when temperatures were at or greater than than 0°C. Furthermore, lower frequency channel observations were more sensitive to these physical temperatures than higher frequencies. Second, the Tb difference between horizontal and vertical polarizations were also negatively correlated with physical temperatures less than 0°C, but not when the physical temperatures were greater than 0°C. In addition, the Tb polarization differences of the lower frequency channels are more sensitive to temperature than for the higher frequency channels. Third, although the snow on the canopy can influence the microwave Tb response, this influence was found to be relatively small compared with other factors, suggesting that the difference of the canopy Tbs during the snow-covered and no-snow-covered periods were not statistically significant.

Maintenance and Exchange of Learning Objects in a Web Services Based e-Learning System

ERIC Educational Resources Information Center

Vossen, Gottfried; Westerkamp, Peter

2004-01-01

"Web services" enable partners to exploit applications via the Internet. Individual services can be composed to build new and more complex ones with additional and more comprehensive functionality. In this paper, we apply the Web service paradigm to electronic learning, and show how to exchange and maintain learning objects is a…

Naval Oceanography Portal

Science.gov Websites

accessible and usable, working in accordance with the Web Content Accessibility Guidelines (WCAG v1.0). If navigation device enabling you to get around this web site using your keyboard. Available access keys This develop a web site that is clear and simple for everybody to use. Validation We have used XHTML 1.0 and

Ontology-Based Approaches to Improve RDF Triple Store

ERIC Educational Resources Information Center

Albahli, Saleh M.

2016-01-01

The World Wide Web enables an easy, instant access to a huge quantity of information. Over the last few decades, a number of improvements have been achieved that helped the web reach its current state. However, the current Internet links documents together without understanding them, and thus, makes the content of web only human-readable rather…

FASTQ quality control dashboard

DOE Office of Scientific and Technical Information (OSTI.GOV)

2016-07-25

FQCDB builds up existing open source software, FastQC, implementing a modern web interface for across parsed output of FastQC. In addition, FQCDB is extensible as a web service to include additional plots of type line, boxplot, or heatmap, across data formatted according to guidelines. The interface is also configurable via more readable JSON format, enabling customization by non-web programmers.

Enabling a Community of Practice: Results of the LSCHE Web Portal Survey

ERIC Educational Resources Information Center

Hoff, Meagan A.; Hodges, Russ; Lin, Yuting; McConnell, Michael C.

2017-01-01

The study explored usage patterns of the Learning Support Centers in Higher Education (LSCHE) web portal, an open educational resource (OER) that serves learning support center professionals. Results of an online survey taken by LSCHE users (N = 41) tracked their self-reported usage and perceived value of resources on the web portal, which…

Academic Libraries and the Semantic Web: What the Future May Hold for Research-Supporting Library Catalogues

ERIC Educational Resources Information Center

Campbell, D. Grant; Fast, Karl V.

2004-01-01

This paper examines how future metadata capabilities could enable academic libraries to exploit information on the emerging Semantic Web in their library catalogues. Whereas current metadata architectures treat the Web as a simple means of interchanging bibliographic data that have been created by libraries, this paper suggests that academic…

Sensor Webs and Virtual Globes: Enabling Understanding of Changes in a partially Glaciated Watershed

NASA Astrophysics Data System (ADS)

Heavner, M.; Fatland, D. R.; Habermann, M.; Berner, L.; Hood, E.; Connor, C.; Galbraith, J.; Knuth, E.; O'Brien, W.

2008-12-01

The University of Alaska Southeast is currently implementing a sensor web identified as the SouthEast Alaska MOnitoring Network for Science, Telecommunications, Education, and Research (SEAMONSTER). SEAMONSTER is operating in the partially glaciated Mendenhall and Lemon Creek Watersheds, in the Juneau area, on the margins of the Juneau Icefield. These watersheds are studied for both 1. long term monitoring of changes, and 2. detection and analysis of transient events (such as glacier lake outburst floods). The heterogeneous sensors (meteorologic, dual frequency GPS, water quality, lake level, etc), power and bandwidth constraints, and competing time scales of interest require autonomous reactivity of the sensor web. They also present challenges for operational management of the sensor web. The harsh conditions on the glaciers provide additional operating constraints. The tight integration of the sensor web and virtual global enabling technology enhance the project in multiple ways. We are utilizing virtual globe infrastructures to enhance both sensor web management and data access. SEAMONSTER utilizes virtual globes for education and public outreach, sensor web management, data dissemination, and enabling collaboration. Using a PosgreSQL with GIS extensions database coupled to the Open Geospatial Consortium (OGC) Geoserver, we generate near-real-time auto-updating geobrowser files of the data in multiple OGC standard formats (e.g KML, WCS). Additionally, embedding wiki pages in this database allows the development of a geospatially aware wiki describing the projects for better public outreach and education. In this presentation we will describe how we have implemented these technologies to date, the lessons learned, and our efforts towards greater OGC standard implementation. A major focus will be on demonstrating how geobrowsers and virtual globes have made this project possible.

Contributions of Traditional Web 1.0 Tools e.g. Email and Web 2.0 Tools e.g. Weblog towards Knowledge Management

ERIC Educational Resources Information Center

Dehinbo, Johnson

2010-01-01

The use of email utilizes the power of Web 1.0 to enable users to access their email from any computer and mobile devices that is connected to the Internet making email valuable in acquiring and transferring knowledge. But the advent of Web 2.0 and social networking seems to indicate certain limitations of email. The use of social networking seems…

Use of seaweed Ulva lactuca for water bioremediation and as feed additive for white shrimp Litopenaeus vannamei.

PubMed

Elizondo-González, Regina; Quiroz-Guzmán, Eduardo; Escobedo-Fregoso, Cristina; Magallón-Servín, Paola; Peña-Rodríguez, Alberto

2018-01-01

Two experimental feeding trials were conducted during four weeks to evaluate the use of Ulva lactuca in shrimp culture: (1) for wastewater bioremediation, and (2) using different inclusion levels of U. lactuca meal in shrimp feed. In feeding trial 1, shrimp reared under seaweed U. lactuca water exchange in a re-circulation system (SWE) resulted in similar growth and feed utilization as shrimp reared with clean water exchange (CWE). Shrimp under no water exchange (NWE) resulted in significant lower growth and higher feed conversion rate (FCR) compared to the other treatments ( p  < 0.05). Nitrogen compounds and phosphate in water from SWE and CWE treatments did not present significant differences during the experimental trial ( p  > 0.05). In feeding trial 2, U. lactuca biomass produced by wastewater bioremediation in SWE treatment were dried and ground to formulate diets containing 0, 1, 2, and 3% U. lactuca meal (0UL, 1UL, 2UL, and 3UL). Shrimp fed the 3 UL diet resulted in a significant ( p  < 0.05) improvement of growth and FCR, and enhanced whole shrimp lipid and carotenoid content by 30 and 60%, respectively, compared to control diet. Seaweed U. lactuca is suggested as a desirable species for wastewater bioremediation in integrated aquaculture systems, and its meal as a good feed additive for farmed shrimp.

Use of seaweed Ulva lactuca for water bioremediation and as feed additive for white shrimp Litopenaeus vannamei

PubMed Central

Elizondo-González, Regina; Quiroz-Guzmán, Eduardo; Escobedo-Fregoso, Cristina; Magallón-Servín, Paola

2018-01-01

Two experimental feeding trials were conducted during four weeks to evaluate the use of Ulva lactuca in shrimp culture: (1) for wastewater bioremediation, and (2) using different inclusion levels of U. lactuca meal in shrimp feed. In feeding trial 1, shrimp reared under seaweed U. lactuca water exchange in a re-circulation system (SWE) resulted in similar growth and feed utilization as shrimp reared with clean water exchange (CWE). Shrimp under no water exchange (NWE) resulted in significant lower growth and higher feed conversion rate (FCR) compared to the other treatments (p < 0.05). Nitrogen compounds and phosphate in water from SWE and CWE treatments did not present significant differences during the experimental trial (p > 0.05). In feeding trial 2, U. lactuca biomass produced by wastewater bioremediation in SWE treatment were dried and ground to formulate diets containing 0, 1, 2, and 3% U. lactuca meal (0UL, 1UL, 2UL, and 3UL). Shrimp fed the 3 UL diet resulted in a significant (p < 0.05) improvement of growth and FCR, and enhanced whole shrimp lipid and carotenoid content by 30 and 60%, respectively, compared to control diet. Seaweed U. lactuca is suggested as a desirable species for wastewater bioremediation in integrated aquaculture systems, and its meal as a good feed additive for farmed shrimp. PMID:29527414

Pharmacogenetic Features of Inhibitors to Cathepsin B that Improve Memory Deficit and Reduce Beta-Amyloid Related to Alzheimer’s Disease

PubMed Central

Hook, Vivian; Hook, Gregory; Kindy, Mark

2015-01-01

Beta-amyloid (Aβ) in brain is a major factor involved in Alzheimer’s disease (AD) that results in severe memory deficit. Our recent studies demonstrate pharmacogenetic differences in the effects of inhibitors of cathepsin B to improve memory and reduce Aβ in different mouse models of AD. The inhibitors improve memory and reduce brain Aβ in mice expressing the wild-type (WT) β-secretase site of human APP, expressed in most AD patients. However, these inhibitors have no effect in mice expressing the rare Swedish (Swe) mutant APP. Knockout of the cathepsin B decreased brain Aβ in mice expressing WT APP, validating cathepsin B as the target. The specificity of cathepsin B to cleave the WT β-secretase site, but not the Swe mutant site, of APP for Aβ production explains the distinct inhibitor responses in the different AD mouse models. In contrast to cathepsin B, the BACE1 β-secretase prefers to cleave the Swe mutant site. Discussion of BACE1 data in the field indicate that they do not preclude cathepsin B as also being a β-secretase. Cathepsin B and BACE1 may participate jointly as β-secretases. Significantly, the majority of AD patients express WT APP and, therefore, inhibitors of cathepsin B represent candidate drugs for AD. PMID:20536395

Anisotropy of Solid Breast Lesions in 2D Shear Wave Elastography is an Indicator of Malignancy.

PubMed

Skerl, Katrin; Vinnicombe, Sarah; Thomson, Kim; McLean, Denis; Giannotti, Elisabetta; Evans, Andrew

2016-01-01

To investigate if anisotropy at two-dimensional shear wave elastography (SWE) suggests malignancy and whether it correlates with prognostic and predictive factors in breast cancer. Study group A of 244 solid breast lesions was imaged with SWE between April 2013 and May 2014. Each lesion was imaged in radial and in antiradial planes, and the maximum elasticity, mean elasticity, and standard deviation were recorded and correlated with benign/malignant status, and if malignant, correlated with conventional predictive and prognostic factors. The results were compared to a study group B of 968 solid breast lesions, which were imaged in sagittal and in axial planes between 2010 and 2013. Neither benign nor malignant lesion anisotropy is plane dependent. However, malignant lesions are more anisotropic than benign lesions (P ≤ 0.001). Anisotropy correlates with increasing elasticity parameters, breast imaging-reporting and data system categories, core biopsy result, and tumor grade. Large cancers are significantly more anisotropic than small cancers (P ≤ 0.001). The optimal anisotropy cutoff threshold for benign/malignant differentiation of 150 kPa(2) achieves the best sensitivity (74%) with a reasonable specificity (63%). Anisotropy may be useful during benign/malignant differentiation of solid breast masses using SWE. Anisotropy also correlates with some prognostic factors in breast cancer. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

Use of shear wave elastography to differentiate benign and malignant breast lesions

PubMed Central

Olgun, Deniz Çebi; Korkmazer, Bora; Kılıç, Fahrettin; Dikici, Atilla Süleyman; Velidedeoğlu, Mehmet; Aydoğan, Fatih; Kantarcı, Fatih; Yılmaz, Mehmet Halit

2014-01-01

PURPOSE We aimed to determine the correlations between the elasticity values of solid breast masses and histopathological findings to define cutoff elasticity values differentiating malignant from benign lesions. MATERIALS and METHODS A total of 115 solid breast lesions of 109 consecutive patients were evaluated prospectively using shear wave elastography (SWE). Two orthogonal elastographic images of each lesion were obtained. Minimum, mean, and maximum elasticity values were calculated in regions of interest placed over the stiffest areas on the two images; we also calculated mass/fat elasticity ratios. Correlation of elastographic measurements with histopathological results were studied. RESULTS Eighty-three benign and thirty-two malignant lesions were histopathologically diagnosed. The minimum, mean, and maximum elasticity values, and the mass/fat elasticity ratios of malignant lesions, were significantly higher than those of benign lesions. The cutoff value was 45.7 kPa for mean elasticity (sensitivity, 96%; specificity, 95%), 54.3 kPa for maximum elasticity (sensitivity, 95%; specificity, 94%), 37.1 kPa for minimum elasticity (sensitivity, 96%; specificity, 95%), and 4.6 for the mass/fat elasticity ratio (sensitivity, 97%; specificity, 95%). CONCLUSION SWE yields additional valuable quantitative data to ultrasonographic examination on solid breast lesions. SWE may serve as a complementary tool for diagnosis of breast lesions. Long-term clinical studies are required to accurately select lesions requiring biopsy. PMID:24509183

WebGLORE: a web service for Grid LOgistic REgression.

PubMed

Jiang, Wenchao; Li, Pinghao; Wang, Shuang; Wu, Yuan; Xue, Meng; Ohno-Machado, Lucila; Jiang, Xiaoqian

2013-12-15

WebGLORE is a free web service that enables privacy-preserving construction of a global logistic regression model from distributed datasets that are sensitive. It only transfers aggregated local statistics (from participants) through Hypertext Transfer Protocol Secure to a trusted server, where the global model is synthesized. WebGLORE seamlessly integrates AJAX, JAVA Applet/Servlet and PHP technologies to provide an easy-to-use web service for biomedical researchers to break down policy barriers during information exchange. http://dbmi-engine.ucsd.edu/webglore3/. WebGLORE can be used under the terms of GNU general public license as published by the Free Software Foundation.

Enabling Cross-Platform Clinical Decision Support through Web-Based Decision Support in Commercial Electronic Health Record Systems: Proposal and Evaluation of Initial Prototype Implementations

PubMed Central

Zhang, Mingyuan; Velasco, Ferdinand T.; Musser, R. Clayton; Kawamoto, Kensaku

2013-01-01

Enabling clinical decision support (CDS) across multiple electronic health record (EHR) systems has been a desired but largely unattained aim of clinical informatics, especially in commercial EHR systems. A potential opportunity for enabling such scalable CDS is to leverage vendor-supported, Web-based CDS development platforms along with vendor-supported application programming interfaces (APIs). Here, we propose a potential staged approach for enabling such scalable CDS, starting with the use of custom EHR APIs and moving towards standardized EHR APIs to facilitate interoperability. We analyzed three commercial EHR systems for their capabilities to support the proposed approach, and we implemented prototypes in all three systems. Based on these analyses and prototype implementations, we conclude that the approach proposed is feasible, already supported by several major commercial EHR vendors, and potentially capable of enabling cross-platform CDS at scale. PMID:24551426

Publishing and Editing of Semantically-Enabled Scientific Metadata Across Multiple Web Platforms: Challenges and Experiences

NASA Astrophysics Data System (ADS)

Patton, E. W.; West, P.; Greer, R.; Jin, B.

2011-12-01

Following on work presented at the 2010 AGU Fall Meeting, we present a number of real-world collections of semantically-enabled scientific metadata ingested into the Tetherless World RDF2HTML system as structured data and presented and edited using that system. Two separate datasets from two different domains (oceanography and solar sciences) are made available using existing web standards and services, e.g. encoded using ontologies represented with the Web Ontology Language (OWL) and stored in a SPARQL endpoint for querying. These datasets are deployed for use in three different web environments, i.e. Drupal, MediaWiki, and a custom web portal written in Java, to highlight the cross-platform nature of the data presentation. Stylesheets used to transform concepts in each domain as well as shared terms into HTML will be presented to show the power of using common ontologies to publish data and support reuse of existing terminologies. In addition, a single domain dataset is shared between two separate portal instances to demonstrate the ability for this system to offer distributed access and modification of content across the Internet. Lastly, we will highlight challenges that arose in the software engineering process, outline the design choices we made in solving those issues, and discuss how future improvements to this and other systems will enable the evolution of distributed, decentralized collaborations for scientific data sharing across multiple research groups.

A User-Centric Knowledge Creation Model in a Web of Object-Enabled Internet of Things Environment

PubMed Central

Kibria, Muhammad Golam; Fattah, Sheik Mohammad Mostakim; Jeong, Kwanghyeon; Chong, Ilyoung; Jeong, Youn-Kwae

2015-01-01

User-centric service features in a Web of Object-enabled Internet of Things environment can be provided by using a semantic ontology that classifies and integrates objects on the World Wide Web as well as shares and merges context-aware information and accumulated knowledge. The semantic ontology is applied on a Web of Object platform to virtualize the real world physical devices and information to form virtual objects that represent the features and capabilities of devices in the virtual world. Detailed information and functionalities of multiple virtual objects are combined with service rules to form composite virtual objects that offer context-aware knowledge-based services, where context awareness plays an important role in enabling automatic modification of the system to reconfigure the services based on the context. Converting the raw data into meaningful information and connecting the information to form the knowledge and storing and reusing the objects in the knowledge base can both be expressed by semantic ontology. In this paper, a knowledge creation model that synchronizes a service logistic model and a virtual world knowledge model on a Web of Object platform has been proposed. To realize the context-aware knowledge-based service creation and execution, a conceptual semantic ontology model has been developed and a prototype has been implemented for a use case scenario of emergency service. PMID:26393609

A User-Centric Knowledge Creation Model in a Web of Object-Enabled Internet of Things Environment.

PubMed

Kibria, Muhammad Golam; Fattah, Sheik Mohammad Mostakim; Jeong, Kwanghyeon; Chong, Ilyoung; Jeong, Youn-Kwae

2015-09-18

User-centric service features in a Web of Object-enabled Internet of Things environment can be provided by using a semantic ontology that classifies and integrates objects on the World Wide Web as well as shares and merges context-aware information and accumulated knowledge. The semantic ontology is applied on a Web of Object platform to virtualize the real world physical devices and information to form virtual objects that represent the features and capabilities of devices in the virtual world. Detailed information and functionalities of multiple virtual objects are combined with service rules to form composite virtual objects that offer context-aware knowledge-based services, where context awareness plays an important role in enabling automatic modification of the system to reconfigure the services based on the context. Converting the raw data into meaningful information and connecting the information to form the knowledge and storing and reusing the objects in the knowledge base can both be expressed by semantic ontology. In this paper, a knowledge creation model that synchronizes a service logistic model and a virtual world knowledge model on a Web of Object platform has been proposed. To realize the context-aware knowledge-based service creation and execution, a conceptual semantic ontology model has been developed and a prototype has been implemented for a use case scenario of emergency service.

Cytoscape tools for the web age: D3.js and Cytoscape.js exporters

PubMed Central

Ono, Keiichiro; Demchak, Barry; Ideker, Trey

2014-01-01

In this paper we present new data export modules for Cytoscape 3 that can generate network files for Cytoscape.js and D3.js. Cytoscape.js exporter is implemented as a core feature of Cytoscape 3, and D3.js exporter is available as a Cytoscape 3 app. These modules enable users to seamlessly export network and table data sets generated in Cytoscape to popular JavaScript library readable formats. In addition, we implemented template web applications for browser-based interactive network visualization that can be used as basis for complex data visualization applications for bioinformatics research. Example web applications created with these tools demonstrate how Cytoscape works in modern data visualization workflows built with traditional desktop tools and emerging web-based technologies. This interactivity enables researchers more flexibility than with static images, thereby greatly improving the quality of insights researchers can gain from them. PMID:25520778

Cytoscape tools for the web age: D3.js and Cytoscape.js exporters.

PubMed

Ono, Keiichiro; Demchak, Barry; Ideker, Trey

2014-01-01

In this paper we present new data export modules for Cytoscape 3 that can generate network files for Cytoscape.js and D3.js. Cytoscape.js exporter is implemented as a core feature of Cytoscape 3, and D3.js exporter is available as a Cytoscape 3 app. These modules enable users to seamlessly export network and table data sets generated in Cytoscape to popular JavaScript library readable formats. In addition, we implemented template web applications for browser-based interactive network visualization that can be used as basis for complex data visualization applications for bioinformatics research. Example web applications created with these tools demonstrate how Cytoscape works in modern data visualization workflows built with traditional desktop tools and emerging web-based technologies. This interactivity enables researchers more flexibility than with static images, thereby greatly improving the quality of insights researchers can gain from them.

A Bookmarking Service for Organizing and Sharing URLs

NASA Technical Reports Server (NTRS)

Keller, Richard M.; Wolfe, Shawn R.; Chen, James R.; Mathe, Nathalie; Rabinowitz, Joshua L.

1997-01-01

Web browser bookmarking facilities predominate as the method of choice for managing URLs. In this paper, we describe some deficiencies of current bookmarking schemes, and examine an alternative to current approaches. We present WebTagger(TM), an implemented prototype of a personal bookmarking service that provides both individuals and groups with a customizable means of organizing and accessing Web-based information resources. In addition, the service enables users to supply feedback on the utility of these resources relative to their information needs, and provides dynamically-updated ranking of resources based on incremental user feedback. Individuals may access the service from anywhere on the Internet, and require no special software. This service greatly simplifies the process of sharing URLs within groups, in comparison with manual methods involving email. The underlying bookmark organization scheme is more natural and flexible than current hierarchical schemes supported by the major Web browsers, and enables rapid access to stored bookmarks.

Useful Sensor Web Capabilities to Enable Progressive Mission Autonomy

NASA Technical Reports Server (NTRS)

Mandl, Dan

2007-01-01

This viewgraph presentation reviews using the Sensor Web capabilities as an enabling technology to allow for progressive autonomy of NASA space missions. The presentation reviews technical challenges for future missions, and some of the capabilities that exist to meet those challenges. To establish the ability of the technology to meet the challenges, experiments were conducted on three missions: Earth Observing 1 (EO-1), Cosmic Hot Interstellar Plasma Spectrometer (CHIPS) and Space Technology 5 (ST-5). These experiments are reviewed.

Optimized Autonomous Space In-situ Sensor-Web for volcano monitoring

USGS Publications Warehouse

Song, W.-Z.; Shirazi, B.; Kedar, S.; Chien, S.; Webb, F.; Tran, D.; Davis, A.; Pieri, D.; LaHusen, R.; Pallister, J.; Dzurisin, D.; Moran, S.; Lisowski, M.

2008-01-01

In response to NASA's announced requirement for Earth hazard monitoring sensor-web technology, a multidisciplinary team involving sensor-network experts (Washington State University), space scientists (JPL), and Earth scientists (USGS Cascade Volcano Observatory (CVO)), is developing a prototype dynamic and scaleable hazard monitoring sensor-web and applying it to volcano monitoring. The combined Optimized Autonomous Space -In-situ Sensor-web (OASIS) will have two-way communication capability between ground and space assets, use both space and ground data for optimal allocation of limited power and bandwidth resources on the ground, and use smart management of competing demands for limited space assets. It will also enable scalability and seamless infusion of future space and in-situ assets into the sensor-web. The prototype will be focused on volcano hazard monitoring at Mount St. Helens, which has been active since October 2004. The system is designed to be flexible and easily configurable for many other applications as well. The primary goals of the project are: 1) integrating complementary space (i.e., Earth Observing One (EO-1) satellite) and in-situ (ground-based) elements into an interactive, autonomous sensor-web; 2) advancing sensor-web power and communication resource management technology; and 3) enabling scalability for seamless infusion of future space and in-situ assets into the sensor-web. To meet these goals, we are developing: 1) a test-bed in-situ array with smart sensor nodes capable of making autonomous data acquisition decisions; 2) efficient self-organization algorithm of sensor-web topology to support efficient data communication and command control; 3) smart bandwidth allocation algorithms in which sensor nodes autonomously determine packet priorities based on mission needs and local bandwidth information in real-time; and 4) remote network management and reprogramming tools. The space and in-situ control components of the system will be integrated such that each element is capable of autonomously tasking the other. Sensor-web data acquisition and dissemination will be accomplished through the use of the Open Geospatial Consortium Sensorweb Enablement protocols. The three-year project will demonstrate end-to-end system performance with the in-situ test-bed at Mount St. Helens and NASA's EO-1 platform. ??2008 IEEE.

Study on the application of shear-wave elastography to thin-layered media and tubular structure: Finite-element analysis and experiment verification

NASA Astrophysics Data System (ADS)

Jang, Jun-keun; Kondo, Kengo; Namita, Takeshi; Yamakawa, Makoto; Shiina, Tsuyoshi

2016-07-01

Shear-wave elastography (SWE) enables the noninvasive and quantitative evaluation of the mechanical properties of human soft tissue. Generally, shear-wave velocity (C S) can be estimated using the time-of-flight (TOF) method. Young’s modulus is then calculated directly from the estimated C S. However, because shear waves in thin-layered media propagate as guided waves, C S cannot be accurately estimated using the conventional TOF method. Leaky Lamb dispersion analysis (LLDA) has recently been proposed to overcome this problem. In this study, we performed both experimental and finite-element (FE) analyses to evaluate the advantages of LLDA over TOF. In FE analysis, we investigated why the conventional TOF is ineffective for thin-layered media. In phantom experiments, C S results estimated using the two methods were compared for 1.5 and 2% agar plates and tube phantoms. Furthermore, it was shown that Lamb waves can be applied to tubular structures by extracting lateral waves traveling in the long axis direction of the tube using a two-dimensional window. Also, the effects of the inner radius and stiffness (or shear wavelength) of the tube on the estimation performance of LLDA were experimentally discussed. In phantom experiments, the results indicated good agreement between LLDA (plate phantoms of 2 mm thickness: 5.0 m/s for 1.5% agar and 7.2 m/s for 2% agar; tube phantoms with 2 mm thickness and 2 mm inner radius: 5.1 m/s for 1.5% agar and 7.0 m/s for 2% agar; tube phantoms with 2 mm thickness and 4 mm inner radius: 5.3 m/s for 1.5% agar and 7.3 m/s for 2% agar) and SWE measurements (bulk phantoms: 5.3 m/s ± 0.27 for 1.5% agar and 7.3 m/s ± 0.54 for 2% agar).

Data as a Service: A Seismic Web Service Pipeline

NASA Astrophysics Data System (ADS)

Martinez, E.

2016-12-01

Publishing data as a service pipeline provides an improved, dynamic approach over static data archives. A service pipeline is a collection of micro web services that each perform a specific task and expose the results of that task. Structured request/response formats allow micro web services to be chained together into a service pipeline to provide more complex results. The U.S. Geological Survey adopted service pipelines to publish seismic hazard and design data supporting both specific and generalized audiences. The seismic web service pipeline starts at source data and exposes probability and deterministic hazard curves, response spectra, risk-targeted ground motions, and seismic design provision metadata. This pipeline supports public/private organizations and individual engineers/researchers. Publishing data as a service pipeline provides a variety of benefits. Exposing the component services enables advanced users to inspect or use the data at each processing step. Exposing a composite service enables new users quick access to published data with a very low barrier to entry. Advanced users may re-use micro web services by chaining them in new ways or injecting new micros services into the pipeline. This allows the user to test hypothesis and compare their results to published results. Exposing data at each step in the pipeline enables users to review and validate the data and process more quickly and accurately. Making the source code open source, per USGS policy, further enables this transparency. Each micro service may be scaled independent of any other micro service. This ensures data remains available and timely in a cost-effective manner regardless of load. Additionally, if a new or more efficient approach to processing the data is discovered, this new approach may replace the old approach at any time, keeping the pipeline running while not affecting other micro services.

Spectral Profiler Probe for In Situ Snow Grain Size and Composition Stratigraphy

NASA Technical Reports Server (NTRS)

Berisford, Daniel F.; Molotch, Noah P.; Painter, Thomas

2012-01-01

An ultimate goal of the climate change, snow science, and hydrology communities is to measure snow water equivalent (SWE) from satellite measurements. Seasonal SWE is highly sensitive to climate change and provides fresh water for much of the world population. Snowmelt from mountainous regions represents the dominant water source for 60 million people in the United States and over one billion people globally. Determination of snow grain sizes comprising mountain snowpack is critical for predicting snow meltwater runoff, understanding physical properties and radiation balance, and providing necessary input for interpreting satellite measurements. Both microwave emission and radar backscatter from the snow are dominated by the snow grain size stratigraphy. As a result, retrieval algorithms for measuring snow water equivalents from orbiting satellites is largely hindered by inadequate knowledge of grain size.

Using EMBL-EBI services via Web interface and programmatically via Web Services

PubMed Central

Lopez, Rodrigo; Cowley, Andrew; Li, Weizhong; McWilliam, Hamish

2015-01-01

The European Bioinformatics Institute (EMBL-EBI) provides access to a wide range of databases and analysis tools that are of key importance in bioinformatics. As well as providing Web interfaces to these resources, Web Services are available using SOAP and REST protocols that enable programmatic access to our resources and allow their integration into other applications and analytical workflows. This unit describes the various options available to a typical researcher or bioinformatician who wishes to use our resources via Web interface or programmatically via a range of programming languages. PMID:25501941

REACTOR - a Concept for establishing a System-of-Systems

NASA Astrophysics Data System (ADS)

Haener, Rainer; Hammitzsch, Martin; Wächter, Joachim

2014-05-01

REACTOR is a working title for activities implementing reliable, emergent, adaptive, and concurrent collaboration on the basis of transactional object repositories. It aims at establishing federations of autonomous yet interoperable systems (Systems-of-Systems), which are able to expose emergent behaviour. Following the principles of event-driven service-oriented architectures (SOA 2.0), REACTOR enables adaptive re-organisation by dynamic delegation of responsibilities and novel yet coherent monitoring strategies by combining information from different domains. Thus it allows collaborative decision-processes across system, discipline, and administrative boundaries. Interoperability is based on two approaches that implement interconnection and communication between existing heterogeneous infrastructures and information systems: Coordinated (orchestration-based) communication and publish/subscribe (choreography-based) communication. Choreography-based communication ensures the autonomy of the participating systems to the highest possible degree but requires the implementation of adapters, which provide functional access to information (publishing/consuming events) via a Message Oriented Middleware (MOM). Any interconnection of the systems (composition of service and message cascades) is established on the basis of global conversations that are enacted by choreographies specifying the expected behaviour of the participating systems with respect to agreed Service Level Agreements (SLA) required by e.g. national authorities. The specification of conversations, maintained in commonly available repositories also enables the utilisation of systems for purposes (evolving) other than initially intended. Orchestration-based communication additionally requires a central component that controls the information transfer via service requests or event processing and also takes responsibility of managing business processes. Commonly available transactional object repositories are well suited to establish brokers, which mediate metadata and semantic information about the resources of all involved systems. This concept has been developed within the project Collaborative, Complex, and Critical Decision-Support in Evolving Crises (TRIDEC) on the basis of semantic registries describing all facets of events and services utilisable for crisis management systems. The implementation utilises an operative infrastructure including an Enterprise Service Bus (ESB), adapters to proprietary sensor systems, a workflow engine, and a broker-based MOM. It also applies current technologies like actor-based frameworks for highly concurrent, distributed, and fault tolerant event-driven applications. Therefore REACTOR implementations are well suited to be hosted in a cloud that provides Infrastructure as a Service (IaaS). To provide low entry barriers for legacy and future systems, REACTOR adapts the principles of Design by Contract (DbC) as well as standardised and common information models like the Sensor Web Enablement (SWE) or the JavaScript Object Notation for geographic features (GeoJSON). REACTOR has been applied exemplarily within two different scenarios, Natural Crisis Management and Industrial Subsurface Development.

Semantic SenseLab: implementing the vision of the Semantic Web in neuroscience

PubMed Central

Samwald, Matthias; Chen, Huajun; Ruttenberg, Alan; Lim, Ernest; Marenco, Luis; Miller, Perry; Shepherd, Gordon; Cheung, Kei-Hoi

2011-01-01

Summary Objective Integrative neuroscience research needs a scalable informatics framework that enables semantic integration of diverse types of neuroscience data. This paper describes the use of the Web Ontology Language (OWL) and other Semantic Web technologies for the representation and integration of molecular-level data provided by several of SenseLab suite of neuroscience databases. Methods Based on the original database structure, we semi-automatically translated the databases into OWL ontologies with manual addition of semantic enrichment. The SenseLab ontologies are extensively linked to other biomedical Semantic Web resources, including the Subcellular Anatomy Ontology, Brain Architecture Management System, the Gene Ontology, BIRNLex and UniProt. The SenseLab ontologies have also been mapped to the Basic Formal Ontology and Relation Ontology, which helps ease interoperability with many other existing and future biomedical ontologies for the Semantic Web. In addition, approaches to representing contradictory research statements are described. The SenseLab ontologies are designed for use on the Semantic Web that enables their integration into a growing collection of biomedical information resources. Conclusion We demonstrate that our approach can yield significant potential benefits and that the Semantic Web is rapidly becoming mature enough to realize its anticipated promises. The ontologies are available online at http://neuroweb.med.yale.edu/senselab/ PMID:20006477

Experimenting with an Evolving Ground/Space-based Software Architecture to Enable Sensor Webs

NASA Technical Reports Server (NTRS)

mandl, Daniel; Frye, Stuart

2005-01-01

A series of ongoing experiments are being conducted at the NASA Goddard Space Flight Center to explore integrated ground and space-based software architectures enabling sensor webs. A sensor web, as defined by Steve Talabac at NASA Goddard Space Flight Center(GSFC), is a coherent set of distributed nodes interconnected by a communications fabric, that collectively behave as a single, dynamically adaptive, observing system. The nodes can be comprised of satellites, ground instruments, computing nodes etc. Sensor web capability requires autonomous management of constellation resources. This becomes progressively more important as more and more satellites share resource, such as communication channels and ground station,s while automatically coordinating their activities. There have been five ongoing activities which include an effort to standardize a set of middleware. This paper will describe one set of activities using the Earth Observing 1 satellite, which used a variety of ground and flight software along with other satellites and ground sensors to prototype a sensor web. This activity allowed us to explore where the difficulties that occur in the assembly of sensor webs given today s technology. We will present an overview of the software system architecture, some key experiments and lessons learned to facilitate better sensor webs in the future.

Semantic SenseLab: Implementing the vision of the Semantic Web in neuroscience.

PubMed

Samwald, Matthias; Chen, Huajun; Ruttenberg, Alan; Lim, Ernest; Marenco, Luis; Miller, Perry; Shepherd, Gordon; Cheung, Kei-Hoi

2010-01-01

Integrative neuroscience research needs a scalable informatics framework that enables semantic integration of diverse types of neuroscience data. This paper describes the use of the Web Ontology Language (OWL) and other Semantic Web technologies for the representation and integration of molecular-level data provided by several of SenseLab suite of neuroscience databases. Based on the original database structure, we semi-automatically translated the databases into OWL ontologies with manual addition of semantic enrichment. The SenseLab ontologies are extensively linked to other biomedical Semantic Web resources, including the Subcellular Anatomy Ontology, Brain Architecture Management System, the Gene Ontology, BIRNLex and UniProt. The SenseLab ontologies have also been mapped to the Basic Formal Ontology and Relation Ontology, which helps ease interoperability with many other existing and future biomedical ontologies for the Semantic Web. In addition, approaches to representing contradictory research statements are described. The SenseLab ontologies are designed for use on the Semantic Web that enables their integration into a growing collection of biomedical information resources. We demonstrate that our approach can yield significant potential benefits and that the Semantic Web is rapidly becoming mature enough to realize its anticipated promises. The ontologies are available online at http://neuroweb.med.yale.edu/senselab/. 2009 Elsevier B.V. All rights reserved.

Data partitioning enables the use of standard SOAP Web Services in genome-scale workflows.

PubMed

Sztromwasser, Pawel; Puntervoll, Pål; Petersen, Kjell

2011-07-26

Biological databases and computational biology tools are provided by research groups around the world, and made accessible on the Web. Combining these resources is a common practice in bioinformatics, but integration of heterogeneous and often distributed tools and datasets can be challenging. To date, this challenge has been commonly addressed in a pragmatic way, by tedious and error-prone scripting. Recently however a more reliable technique has been identified and proposed as the platform that would tie together bioinformatics resources, namely Web Services. In the last decade the Web Services have spread wide in bioinformatics, and earned the title of recommended technology. However, in the era of high-throughput experimentation, a major concern regarding Web Services is their ability to handle large-scale data traffic. We propose a stream-like communication pattern for standard SOAP Web Services, that enables efficient flow of large data traffic between a workflow orchestrator and Web Services. We evaluated the data-partitioning strategy by comparing it with typical communication patterns on an example pipeline for genomic sequence annotation. The results show that data-partitioning lowers resource demands of services and increases their throughput, which in consequence allows to execute in-silico experiments on genome-scale, using standard SOAP Web Services and workflows. As a proof-of-principle we annotated an RNA-seq dataset using a plain BPEL workflow engine.

COEUS: “semantic web in a box” for biomedical applications

PubMed Central

2012-01-01

Background As the “omics” revolution unfolds, the growth in data quantity and diversity is bringing about the need for pioneering bioinformatics software, capable of significantly improving the research workflow. To cope with these computer science demands, biomedical software engineers are adopting emerging semantic web technologies that better suit the life sciences domain. The latter’s complex relationships are easily mapped into semantic web graphs, enabling a superior understanding of collected knowledge. Despite increased awareness of semantic web technologies in bioinformatics, their use is still limited. Results COEUS is a new semantic web framework, aiming at a streamlined application development cycle and following a “semantic web in a box” approach. The framework provides a single package including advanced data integration and triplification tools, base ontologies, a web-oriented engine and a flexible exploration API. Resources can be integrated from heterogeneous sources, including CSV and XML files or SQL and SPARQL query results, and mapped directly to one or more ontologies. Advanced interoperability features include REST services, a SPARQL endpoint and LinkedData publication. These enable the creation of multiple applications for web, desktop or mobile environments, and empower a new knowledge federation layer. Conclusions The platform, targeted at biomedical application developers, provides a complete skeleton ready for rapid application deployment, enhancing the creation of new semantic information systems. COEUS is available as open source at http://bioinformatics.ua.pt/coeus/. PMID:23244467

COEUS: "semantic web in a box" for biomedical applications.

PubMed

Lopes, Pedro; Oliveira, José Luís

2012-12-17

As the "omics" revolution unfolds, the growth in data quantity and diversity is bringing about the need for pioneering bioinformatics software, capable of significantly improving the research workflow. To cope with these computer science demands, biomedical software engineers are adopting emerging semantic web technologies that better suit the life sciences domain. The latter's complex relationships are easily mapped into semantic web graphs, enabling a superior understanding of collected knowledge. Despite increased awareness of semantic web technologies in bioinformatics, their use is still limited. COEUS is a new semantic web framework, aiming at a streamlined application development cycle and following a "semantic web in a box" approach. The framework provides a single package including advanced data integration and triplification tools, base ontologies, a web-oriented engine and a flexible exploration API. Resources can be integrated from heterogeneous sources, including CSV and XML files or SQL and SPARQL query results, and mapped directly to one or more ontologies. Advanced interoperability features include REST services, a SPARQL endpoint and LinkedData publication. These enable the creation of multiple applications for web, desktop or mobile environments, and empower a new knowledge federation layer. The platform, targeted at biomedical application developers, provides a complete skeleton ready for rapid application deployment, enhancing the creation of new semantic information systems. COEUS is available as open source at http://bioinformatics.ua.pt/coeus/.

Modelling the snowmelt and the snow water equivalent by creating a simplified energy balance conceptual snow model

NASA Astrophysics Data System (ADS)

Riboust, Philippe; Thirel, Guillaume; Le Moine, Nicolas; Ribstein, Pierre

2016-04-01

A better knowledge of the accumulated snow on the watersheds will help flood forecasting centres and hydro-power companies to predict the amount of water released during spring snowmelt. Since precipitations gauges are sparse at high elevations and integrative measurements of the snow accumulated on watershed surface are hard to obtain, using snow models is an adequate way to estimate snow water equivalent (SWE) on watersheds. In addition to short term prediction, simulating accurately SWE with snow models should have many advantages. Validating the snow module on both SWE and snowmelt should give a more reliable model for climate change studies or regionalization for ungauged watersheds. The aim of this study is to create a new snow module, which has a structure that allows the use of measured snow data for calibration or assimilation. Energy balance modelling seems to be the logical choice for designing a model in which internal variables, such as SWE, could be compared to observations. Physical models are complex, needing high computational resources and many different types of inputs that are not widely measured at meteorological stations. At the opposite, simple conceptual degree-day models offer to simulate snowmelt using only temperature and precipitation as inputs with fast computing. Its major drawback is to be empirical, i.e. not taking into account all of the processes of the energy balance, which makes this kind of model more difficult to use when willing to compare SWE to observed measurements. In order to reach our objectives, we created a snow model structured by a simplified energy balance where each of the processes is empirically parameterized in order to be calculated using only temperature, precipitation and cloud cover variables. This model's structure is similar to the one created by M.T. Walter (2005), where parameterizations from the literature were used to compute all of the processes of the energy balance. The conductive fluxes into the snowpack were modelled by using analytical solutions to the heat equation taking phase change into account. This approach has the advantage to use few forcing variables and to take into account all the processes of the energy balance. Indeed, the simulations should be quick enough to allow, for example, ensemble prediction or simulation of numerous basins, more easily than physical snow models. The snow module formulation has been completed and is in its validation phase using data from the experimental station of Col de Porte, Alpes, France. Data from the US SNOTEL product will be used in order to test the model structure on a larger scale and to test diverse calibration procedures, since the aim is to use it on a basin scale for discharge modelling purposes.

Ultrasound elastography of the lower uterine segment in women with a previous cesarean section: Comparison of in-/ex-vivo elastography versus tensile-stress-strain-rupture analysis.

PubMed

Seliger, Gregor; Chaoui, Katharina; Lautenschläger, Christine; Jenderka, Klaus-Vitold; Kunze, Christian; Hiller, Grit Gesine Ruth; Tchirikov, Michael

2018-06-01

The purpose of this study was to assess, if the biomechanical properties of the lower uterine segment (LUS) in women with a previous cesarean section (CS) can be determined by ultrasound (US) elastography. The first aim was to establish an ex-vivo LUS tensile-stress-strain-rupture(break point) analysis with the possibility of simultaneously using US elastography. The second aim was to investigate the relationship between measurement results of LUS stiffness using US elastography in-/ex-vivo with results of tensile-stress-strain-rupture analysis, and to compare different US elastography LUS-stiffness-measurement methods ex-vivo. An explorative experimental, in-/ex-vivo US study of women with previous CS was conducted. LUS elasticity was measured by point Shear Wave Elastography (pSWE) and bidimensional Shear-Wave-Elastography (2D-SWE) first in-vivo during preoperative examination within 24 h before repeat CS (including resection of the thinnest part of the LUS = uterine scar area during CS), second within 1 h after operation during the ex-vivo experiment, followed by tensile-stress-strain-rupture analysis. Pearson's correlation coefficient and scatter plots, Bland-Altman plots and paired T-tests, were used. Thirty three women were included in the study; elastography measurements n = 1412. The feasibility of ex-vivo assessment of LUS by quantitative US elastography using pSWE and 2D-SWE to detect stiffness of LUS was demonstrated. The strongest correlation with tensile-stress-strain analysis was found in the US elastography examination carried out with 2D-SWE (0.78, p < 0.001, 95%CI [0.48, 0.92]). The laboratory experiment illustrated that, the break point - as a surrogate marker for the risk of rupture of the LUS after CS - is linearly dependent on the thickness of the LUS in the scar area (Coefficient of correlation: 0.79, p < 0.001, 95%CI [0.55, 0.91]). Two extremely stiff LUS-specimens (outlier or extreme values) rupture even at less stroke/strain than would be expected by their thickness. This study confirms that US elastography can help in determining viscoelastic properties of the LUS in women with a previous CS. The data from our small series are promising. However whether individual extreme values of high stiffness and consecutive restricted biomechanical resilience can explain the phenomenon of rupture during TOLAC in cases of LUS with adequate thickness remains a question which prospective trials have to analyze before US elastography can be introduced into clinical practice. Copyright © 2018 Elsevier B.V. All rights reserved.

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Two-Year Outcomes of the Enabling Mothers to Prevent Pediatric Obesity through Web-Based Education and Reciprocal Determinism (EMPOWER) Randomized Control Trial

ERIC Educational Resources Information Center

Knowlden, Adam P.; Conrad, Eric

2018-01-01

Background: Childhood overweight and obesity is a public health epidemic with far-reaching medical, economic, and quality of life consequences. Brief, web-based interventions have received increased attention for their potential to combat childhood obesity. The purpose of our study was to evaluate a web-based, maternal-facilitated childhood…