Science.gov

Sample records for complex event extraction

  1. Event extraction with complex event classification using rich features.

    PubMed

    Miwa, Makoto; Saetre, Rune; Kim, Jin-Dong; Tsujii, Jun'ichi

    2010-02-01

    Biomedical Natural Language Processing (BioNLP) attempts to capture biomedical phenomena from texts by extracting relations between biomedical entities (i.e. proteins and genes). Traditionally, only binary relations have been extracted from large numbers of published papers. Recently, more complex relations (biomolecular events) have also been extracted. Such events may include several entities or other relations. To evaluate the performance of the text mining systems, several shared task challenges have been arranged for the BioNLP community. With a common and consistent task setting, the BioNLP'09 shared task evaluated complex biomolecular events such as binding and regulation.Finding these events automatically is important in order to improve biomedical event extraction systems. In the present paper, we propose an automatic event extraction system, which contains a model for complex events, by solving a classification problem with rich features. The main contributions of the present paper are: (1) the proposal of an effective bio-event detection method using machine learning, (2) provision of a high-performance event extraction system, and (3) the execution of a quantitative error analysis. The proposed complex (binding and regulation) event detector outperforms the best system from the BioNLP'09 shared task challenge. PMID:20183879

  2. Complex event extraction at PubMed scale

    PubMed Central

    Björne, Jari; Ginter, Filip; Pyysalo, Sampo; Tsujii, Jun'ichi; Salakoski, Tapio

    2010-01-01

    Motivation: There has recently been a notable shift in biomedical information extraction (IE) from relation models toward the more expressive event model, facilitated by the maturation of basic tools for biomedical text analysis and the availability of manually annotated resources. The event model allows detailed representation of complex natural language statements and can support a number of advanced text mining applications ranging from semantic search to pathway extraction. A recent collaborative evaluation demonstrated the potential of event extraction systems, yet there have so far been no studies of the generalization ability of the systems nor the feasibility of large-scale extraction. Results: This study considers event-based IE at PubMed scale. We introduce a system combining publicly available, state-of-the-art methods for domain parsing, named entity recognition and event extraction, and test the system on a representative 1% sample of all PubMed citations. We present the first evaluation of the generalization performance of event extraction systems to this scale and show that despite its computational complexity, event extraction from the entire PubMed is feasible. We further illustrate the value of the extraction approach through a number of analyses of the extracted information. Availability: The event detection system and extracted data are open source licensed and available at http://bionlp.utu.fi/. Contact: jari.bjorne@utu.fi PMID:20529932

  3. Improving the extraction of complex regulatory events from scientific text by using ontology-based inference

    PubMed Central

    2011-01-01

    Background The extraction of complex events from biomedical text is a challenging task and requires in-depth semantic analysis. Previous approaches associate lexical and syntactic resources with ontologies for the semantic analysis, but fall short in testing the benefits from the use of domain knowledge. Results We developed a system that deduces implicit events from explicitly expressed events by using inference rules that encode domain knowledge. We evaluated the system with the inference module on three tasks: First, when tested against a corpus with manually annotated events, the inference module of our system contributes 53.2% of correct extractions, but does not cause any incorrect results. Second, the system overall reproduces 33.1% of the transcription regulatory events contained in RegulonDB (up to 85.0% precision) and the inference module is required for 93.8% of the reproduced events. Third, we applied the system with minimum adaptations to the identification of cell activity regulation events, confirming that the inference improves the performance of the system also on this task. Conclusions Our research shows that the inference based on domain knowledge plays a significant role in extracting complex events from text. This approach has great potential in recognizing the complex concepts of such biomedical ontologies as Gene Ontology in the literature. PMID:22166672

  4. Complex Biological Event Extraction from Full Text using Signatures of Linguistic and Semantic Features

    SciTech Connect

    McGrath, Liam R.; Domico, Kelly O.; Corley, Courtney D.; Webb-Robertson, Bobbie-Jo M.

    2011-06-24

    Building on technical advances from the BioNLP 2009 Shared Task Challenge, the 2011 challenge sets forth to generalize techniques to other complex biological event extraction tasks. In this paper, we present the implementation and evaluation of a signature-based machine-learning technique to predict events from full texts of infectious disease documents. Specifically, our approach uses novel signatures composed of traditional linguistic features and semantic knowledge to predict event triggers and their candidate arguments. Using a leave-one out analysis, we report the contribution of linguistic and shallow semantic features in the trigger prediction and candidate argument extraction. Lastly, we examine evaluations and posit causes for errors of infectious disease track subtasks.

  5. Complex Event Recognition Architecture

    NASA Technical Reports Server (NTRS)

    Fitzgerald, William A.; Firby, R. James

    2009-01-01

    Complex Event Recognition Architecture (CERA) is the name of a computational architecture, and software that implements the architecture, for recognizing complex event patterns that may be spread across multiple streams of input data. One of the main components of CERA is an intuitive event pattern language that simplifies what would otherwise be the complex, difficult tasks of creating logical descriptions of combinations of temporal events and defining rules for combining information from different sources over time. In this language, recognition patterns are defined in simple, declarative statements that combine point events from given input streams with those from other streams, using conjunction, disjunction, and negation. Patterns can be built on one another recursively to describe very rich, temporally extended combinations of events. Thereafter, a run-time matching algorithm in CERA efficiently matches these patterns against input data and signals when patterns are recognized. CERA can be used to monitor complex systems and to signal operators or initiate corrective actions when anomalous conditions are recognized. CERA can be run as a stand-alone monitoring system, or it can be integrated into a larger system to automatically trigger responses to changing environments or problematic situations.

  6. Biomedical Relation Extraction: From Binary to Complex

    PubMed Central

    Zhong, Dayou

    2014-01-01

    Biomedical relation extraction aims to uncover high-quality relations from life science literature with high accuracy and efficiency. Early biomedical relation extraction tasks focused on capturing binary relations, such as protein-protein interactions, which are crucial for virtually every process in a living cell. Information about these interactions provides the foundations for new therapeutic approaches. In recent years, more interests have been shifted to the extraction of complex relations such as biomolecular events. While complex relations go beyond binary relations and involve more than two arguments, they might also take another relation as an argument. In the paper, we conduct a thorough survey on the research in biomedical relation extraction. We first present a general framework for biomedical relation extraction and then discuss the approaches proposed for binary and complex relation extraction with focus on the latter since it is a much more difficult task compared to binary relation extraction. Finally, we discuss challenges that we are facing with complex relation extraction and outline possible solutions and future directions. PMID:25214883

  7. Extracting semantically enriched events from biomedical literature

    PubMed Central

    2012-01-01

    Background Research into event-based text mining from the biomedical literature has been growing in popularity to facilitate the development of advanced biomedical text mining systems. Such technology permits advanced search, which goes beyond document or sentence-based retrieval. However, existing event-based systems typically ignore additional information within the textual context of events that can determine, amongst other things, whether an event represents a fact, hypothesis, experimental result or analysis of results, whether it describes new or previously reported knowledge, and whether it is speculated or negated. We refer to such contextual information as meta-knowledge. The automatic recognition of such information can permit the training of systems allowing finer-grained searching of events according to the meta-knowledge that is associated with them. Results Based on a corpus of 1,000 MEDLINE abstracts, fully manually annotated with both events and associated meta-knowledge, we have constructed a machine learning-based system that automatically assigns meta-knowledge information to events. This system has been integrated into EventMine, a state-of-the-art event extraction system, in order to create a more advanced system (EventMine-MK) that not only extracts events from text automatically, but also assigns five different types of meta-knowledge to these events. The meta-knowledge assignment module of EventMine-MK performs with macro-averaged F-scores in the range of 57-87% on the BioNLP’09 Shared Task corpus. EventMine-MK has been evaluated on the BioNLP’09 Shared Task subtask of detecting negated and speculated events. Our results show that EventMine-MK can outperform other state-of-the-art systems that participated in this task. Conclusions We have constructed the first practical system that extracts both events and associated, detailed meta-knowledge information from biomedical literature. The automatically assigned meta-knowledge information

  8. Combining joint models for biomedical event extraction

    PubMed Central

    2012-01-01

    Background We explore techniques for performing model combination between the UMass and Stanford biomedical event extraction systems. Both sub-components address event extraction as a structured prediction problem, and use dual decomposition (UMass) and parsing algorithms (Stanford) to find the best scoring event structure. Our primary focus is on stacking where the predictions from the Stanford system are used as features in the UMass system. For comparison, we look at simpler model combination techniques such as intersection and union which require only the outputs from each system and combine them directly. Results First, we find that stacking substantially improves performance while intersection and union provide no significant benefits. Second, we investigate the graph properties of event structures and their impact on the combination of our systems. Finally, we trace the origins of events proposed by the stacked model to determine the role each system plays in different components of the output. We learn that, while stacking can propose novel event structures not seen in either base model, these events have extremely low precision. Removing these novel events improves our already state-of-the-art F1 to 56.6% on the test set of Genia (Task 1). Overall, the combined system formed via stacking ("FAUST") performed well in the BioNLP 2011 shared task. The FAUST system obtained 1st place in three out of four tasks: 1st place in Genia Task 1 (56.0% F1) and Task 2 (53.9%), 2nd place in the Epigenetics and Post-translational Modifications track (35.0%), and 1st place in the Infectious Diseases track (55.6%). Conclusion We present a state-of-the-art event extraction system that relies on the strengths of structured prediction and model combination through stacking. Akin to results on other tasks, stacking outperforms intersection and union and leads to very strong results. The utility of model combination hinges on complementary views of the data, and we show that our

  9. Extracting mineral system event histories from geophysical and geochemical data in geologically complex terrain - an example from the southeastern Fennoscandian Shield.

    NASA Astrophysics Data System (ADS)

    Sorjonen-Ward, Peter; Kontinen, Asko; Lerssi, Jouni; Mertanen, Satu; Molnar, Ferenc; O'Brien, Hugh; Pohjolainen, Esa; Halla, Jaana; Korhonen, Fawna; Mattila, Jussi

    2015-04-01

    The mineral systems concept is intended to extend and inform exploration capability, through understanding processes of metal extraction, transport and precipitation within a well-defined architectural framework, as opposed to simple - or even sophisticated - targeting of geophysical or geochemical anomalies. Given that geophysical and geochemical data represent a summation of all events and processes that have affected a body of rock, the use of advanced inversion techniques could be impeded unless we can extract an accurate event history and derive a comprehensive understanding of the history of hydrothermal events and their structural framework, even in a qualitative sense. In ideal cases, we may be able to place age constraints using isotopes or paleomagnetism, if hydrothermal mineral reactions enhance (or disperse) geochemical and geophysical signals. Given a the tendency for deformation in the brittle regime to occur preferentially by reactivation of existing zones of weakness, we might also expect a progressive linear enhancement or dilution of anomalies, where fluid-flow is focused within permeable fault zones. We illustrate these issues through an analysis of event histories and their relationship to diverse mineralization styles and episodes in the southeastern part of the Fennoscandian Shield, where the oldest mineral systems are represented by orogenic gold deposits in Neoarchean greenstone belts and the youngest events are recorded locally by Paleozoic crystallization of uraninite in repeatedly reactivated fault zones. The Neoarchean Karelian craton was subjected to thermal reworking as the foreland terrain to the 1.9-1.8 Ga Svecofennian Orogeny, as demonstrated by resetting of K-Ar, Ar-Ar, Rb-Sr and locally Pb-Pb isotopic systems in feldspars and pyrite, both within gold deposits, and regionally. However, retention of Archean strain patterns and observations of the strain state of Proterozoifc dyke swarms indicate an essentially brittle response, with

  10. Event oriented dictionary learning for complex event detection.

    PubMed

    Yan, Yan; Yang, Yi; Meng, Deyu; Liu, Gaowen; Tong, Wei; Hauptmann, Alexander G; Sebe, Nicu

    2015-06-01

    Complex event detection is a retrieval task with the goal of finding videos of a particular event in a large-scale unconstrained Internet video archive, given example videos and text descriptions. Nowadays, different multimodal fusion schemes of low-level and high-level features are extensively investigated and evaluated for the complex event detection task. However, how to effectively select the high-level semantic meaningful concepts from a large pool to assist complex event detection is rarely studied in the literature. In this paper, we propose a novel strategy to automatically select semantic meaningful concepts for the event detection task based on both the events-kit text descriptions and the concepts high-level feature descriptions. Moreover, we introduce a novel event oriented dictionary representation based on the selected semantic concepts. Toward this goal, we leverage training images (frames) of selected concepts from the semantic indexing dataset with a pool of 346 concepts, into a novel supervised multitask lp -norm dictionary learning framework. Extensive experimental results on TRECVID multimedia event detection dataset demonstrate the efficacy of our proposed method. PMID:25794390

  11. Extracting biomedical events from pairs of text entities

    PubMed Central

    2015-01-01

    Background Huge amounts of electronic biomedical documents, such as molecular biology reports or genomic papers are generated daily. Nowadays, these documents are mainly available in the form of unstructured free texts, which require heavy processing for their registration into organized databases. This organization is instrumental for information retrieval, enabling to answer the advanced queries of researchers and practitioners in biology, medicine, and related fields. Hence, the massive data flow calls for efficient automatic methods of text-mining that extract high-level information, such as biomedical events, from biomedical text. The usual computational tools of Natural Language Processing cannot be readily applied to extract these biomedical events, due to the peculiarities of the domain. Indeed, biomedical documents contain highly domain-specific jargon and syntax. These documents also describe distinctive dependencies, making text-mining in molecular biology a specific discipline. Results We address biomedical event extraction as the classification of pairs of text entities into the classes corresponding to event types. The candidate pairs of text entities are recursively provided to a multiclass classifier relying on Support Vector Machines. This recursive process extracts events involving other events as arguments. Compared to joint models based on Markov Random Fields, our model simplifies inference and hence requires shorter training and prediction times along with lower memory capacity. Compared to usual pipeline approaches, our model passes over a complex intermediate problem, while making a more extensive usage of sophisticated joint features between text entities. Our method focuses on the core event extraction of the Genia task of BioNLP challenges yielding the best result reported so far on the 2013 edition. PMID:26201478

  12. Controlling extreme events on complex networks

    NASA Astrophysics Data System (ADS)

    Chen, Yu-Zhong; Huang, Zi-Gang; Lai, Ying-Cheng

    2014-08-01

    Extreme events, a type of collective behavior in complex networked dynamical systems, often can have catastrophic consequences. To develop effective strategies to control extreme events is of fundamental importance and practical interest. Utilizing transportation dynamics on complex networks as a prototypical setting, we find that making the network ``mobile'' can effectively suppress extreme events. A striking, resonance-like phenomenon is uncovered, where an optimal degree of mobility exists for which the probability of extreme events is minimized. We derive an analytic theory to understand the mechanism of control at a detailed and quantitative level, and validate the theory numerically. Implications of our finding to current areas such as cybersecurity are discussed.

  13. Region extraction from complex shapes.

    PubMed

    Nevins, A J

    1982-05-01

    An algorithm is described which extracts primitive regions (i.e., convex, spiral shaped, and biconcave lens) from complex shapes. The interior region bounded by the shape is decomposed by first slicing it into a set of convex subregions and then rotating and dissolving the various boundaries between subregions until a satisfactory decomposition is obtained. The same algorithm also is used to decompose the exterior region between the shape and its convex hull. The algorithm has been implemented as an Algol-W computer program for the UNIVAC 90/80 and results of running the program are presented for a wide variety of complex shapes. These results compare favorably with the experience reported by previous programs. PMID:21869069

  14. Deep Convective Event extraction procedure: first results

    NASA Astrophysics Data System (ADS)

    Berges, Jean Claude; Beltrando, Gérard; Cacault, Philippe

    2015-04-01

    The tropopause temperature is one of the rare non ambiguous threshold which can be applied to geostationary infra-red measurements. Therefore a straightforward procedure to delineate in space and time Deep Convective Event (DCE) is first to binarize according to this threshold and then to apply a 3D connectivity on successive 10.8 µm satellite images. This process circumnavigate the issue of splitting or merging systems as extracted DCE are only 3D volumes. A key point of this method is that it does not require any local tuning parameter and thus is well suited for building long term climatology. A specific algorithm has been developed to optimize long series data processing and then applied on 18 months database of MSG, MET7 and MTSAT. This presentation will not address the issue of actual rainfall estimation but will focus on behavior of DCE seen as a proxy for intense precipitation event. Basic morphological parameters, such as duration or maximum area, are extracted and related with ground and upper air parameters. Some well known features appear clearly: continent/sea difference, diurnal cycle on land. A more innovative result is the relationship with elevation which appears strong but irregular. The relief triggering effect on DCE appears clearly. In strong contrast with orography, the vegetation cover does not show any clear dependence beyond DCE frequency. Upper air data are supplied by NCEP and ECMWF. Although total precipitable water content is related both with DCE frequency and mean size, such a relationship does not appear for low level winds. This observation does not match with theoretical results which emphasize on wind shear in low troposphere. A possible explanation should rely in limits of deep convection representation in weather reanalysis models. These first results suggest that DCE extraction procedure on one hand is stable enough to run on an operational basis and on another hand can bring significant information. As it relies on the 10

  15. Controlling extreme events on complex networks

    PubMed Central

    Chen, Yu-Zhong; Huang, Zi-Gang; Lai, Ying-Cheng

    2014-01-01

    Extreme events, a type of collective behavior in complex networked dynamical systems, often can have catastrophic consequences. To develop effective strategies to control extreme events is of fundamental importance and practical interest. Utilizing transportation dynamics on complex networks as a prototypical setting, we find that making the network “mobile” can effectively suppress extreme events. A striking, resonance-like phenomenon is uncovered, where an optimal degree of mobility exists for which the probability of extreme events is minimized. We derive an analytic theory to understand the mechanism of control at a detailed and quantitative level, and validate the theory numerically. Implications of our finding to current areas such as cybersecurity are discussed. PMID:25131344

  16. Controlling extreme events on complex networks.

    PubMed

    Chen, Yu-Zhong; Huang, Zi-Gang; Lai, Ying-Cheng

    2014-01-01

    Extreme events, a type of collective behavior in complex networked dynamical systems, often can have catastrophic consequences. To develop effective strategies to control extreme events is of fundamental importance and practical interest. Utilizing transportation dynamics on complex networks as a prototypical setting, we find that making the network "mobile" can effectively suppress extreme events. A striking, resonance-like phenomenon is uncovered, where an optimal degree of mobility exists for which the probability of extreme events is minimized. We derive an analytic theory to understand the mechanism of control at a detailed and quantitative level, and validate the theory numerically. Implications of our finding to current areas such as cybersecurity are discussed. PMID:25131344

  17. TEES 2.2: Biomedical Event Extraction for Diverse Corpora

    PubMed Central

    2015-01-01

    Background The Turku Event Extraction System (TEES) is a text mining program developed for the extraction of events, complex biomedical relationships, from scientific literature. Based on a graph-generation approach, the system detects events with the use of a rich feature set built via dependency parsing. The TEES system has achieved record performance in several of the shared tasks of its domain, and continues to be used in a variety of biomedical text mining tasks. Results The TEES system was quickly adapted to the BioNLP'13 Shared Task in order to provide a public baseline for derived systems. An automated approach was developed for learning the underlying annotation rules of event type, allowing immediate adaptation to the various subtasks, and leading to a first place in four out of eight tasks. The system for the automated learning of annotation rules is further enhanced in this paper to the point of requiring no manual adaptation to any of the BioNLP'13 tasks. Further, the scikit-learn machine learning library is integrated into the system, bringing a wide variety of machine learning methods usable with TEES in addition to the default SVM. A scikit-learn ensemble method is also used to analyze the importances of the features in the TEES feature sets. Conclusions The TEES system was introduced for the BioNLP'09 Shared Task and has since then demonstrated good performance in several other shared tasks. By applying the current TEES 2.2 system to multiple corpora from these past shared tasks an overarching analysis of the most promising methods and possible pitfalls in the evolving field of biomedical event extraction are presented. PMID:26551925

  18. Uranium extraction by complexation with siderophores

    NASA Astrophysics Data System (ADS)

    Bahamonde Castro, Cristina

    One of the major concerns of energy production is the environmental impact associated with the extraction of natural resources. Nuclear energy fuel is obtained from uranium, an abundant and naturally occurring element in the environment, but the currently used techniques for uranium extraction leave either a significant fingerprint (open pit mines) or a chemical residue that alters the pH of the environment (acid or alkali leaching). It is therefore clear that a new and greener approach to uranium extraction is needed. Bioleaching is one potential alternative. In bioleaching, complexants naturally produced from fungi or bacteria may be used to extract the uranium. In the following research, the siderophore enterobactin, which is naturally produced by bacteria to extract and solubilize iron from the environment, is evaluated to determine its potential for complexing with uranium. To determine whether enterobactin could be used for uranium extraction, its acid dissociation and its binding strength with the metal of interest must be determined. Due to the complexity of working with radioactive materials, lanthanides were used as analogs for uranium. In addition, polyprotic acids were used as structural and chemical analogs for the siderophore during method development. To evaluate the acid dissociation of enterobactin and the subsequent binding constants with lanthanides, three different analytical techniques were studied including: potentiometric titration, UltraViolet Visible (UV-Vis) spectrophotometry and Isothermal Titration Calorimetry (ITC). After evaluation of three techniques, a combination of ITC and potentiometric titrations was deemed to be the most viable way for studying the siderophore of interest. The results obtained from these studies corroborate the ideal pH range for enterobactin complexation to the lanthanide of interest and pave the way for determining the strength of complexation relative to other naturally occurring metals. Ultimately, this

  19. Extraction of potential adverse drug events from medical case reports

    PubMed Central

    2012-01-01

    The sheer amount of information about potential adverse drug events published in medical case reports pose major challenges for drug safety experts to perform timely monitoring. Efficient strategies for identification and extraction of information about potential adverse drug events from free‐text resources are needed to support pharmacovigilance research and pharmaceutical decision making. Therefore, this work focusses on the adaptation of a machine learning‐based system for the identification and extraction of potential adverse drug event relations from MEDLINE case reports. It relies on a high quality corpus that was manually annotated using an ontology‐driven methodology. Qualitative evaluation of the system showed robust results. An experiment with large scale relation extraction from MEDLINE delivered under‐identified potential adverse drug events not reported in drug monographs. Overall, this approach provides a scalable auto‐assistance platform for drug safety professionals to automatically collect potential adverse drug events communicated as free‐text data. PMID:23256479

  20. An Overview of Biomolecular Event Extraction from Scientific Documents

    PubMed Central

    Vanegas, Jorge A.; Matos, Sérgio; González, Fabio; Oliveira, José L.

    2015-01-01

    This paper presents a review of state-of-the-art approaches to automatic extraction of biomolecular events from scientific texts. Events involving biomolecules such as genes, transcription factors, or enzymes, for example, have a central role in biological processes and functions and provide valuable information for describing physiological and pathogenesis mechanisms. Event extraction from biomedical literature has a broad range of applications, including support for information retrieval, knowledge summarization, and information extraction and discovery. However, automatic event extraction is a challenging task due to the ambiguity and diversity of natural language and higher-level linguistic phenomena, such as speculations and negations, which occur in biological texts and can lead to misunderstanding or incorrect interpretation. Many strategies have been proposed in the last decade, originating from different research areas such as natural language processing, machine learning, and statistics. This review summarizes the most representative approaches in biomolecular event extraction and presents an analysis of the current state of the art and of commonly used methods, features, and tools. Finally, current research trends and future perspectives are also discussed. PMID:26587051

  1. Improved Automated Seismic Event Extraction Using Machine Learning

    NASA Astrophysics Data System (ADS)

    Mackey, L.; Kleiner, A.; Jordan, M. I.

    2009-12-01

    Like many organizations engaged in seismic monitoring, the Preparatory Commission for the Comprehensive Test Ban Treaty Organization collects and processes seismic data from a large network of sensors. This data is continuously transmitted to a central data center, and bulletins of seismic events are automatically extracted. However, as for many such automated systems at present, the inaccuracy of this extraction necessitates substantial human analyst review effort. A significant opportunity for improvement thus lies in the fact that these systems currently fail to fully utilize the valuable repository of historical data provided by prior analyst reviews. In this work, we present the results of the application of machine learning approaches to several fundamental sub-tasks in seismic event extraction. These methods share as a common theme the use of historical analyst-reviewed bulletins as ground truth from which they extract relevant patterns to accomplish the desired goals. For instance, we demonstrate the effectiveness of classification and ranking methods for the identification of false events -- that is, those which will be invalidated and discarded by analysts -- in automated bulletins. We also show gains in the accuracy of seismic phase identification via the use of classification techniques to automatically assign seismic phase labels to station detections. Furthermore, we examine the potential of historical association data to inform the direct association of new signal detections with their corresponding seismic events. Empirical results are based upon parametric historical seismic detection and event data received from the Preparatory Commission for the Comprehensive Test Ban Treaty Organization.

  2. Adaptable, high recall, event extraction system with minimal configuration

    PubMed Central

    2015-01-01

    Background Biomedical event extraction has been a major focus of biomedical natural language processing (BioNLP) research since the first BioNLP shared task was held in 2009. Accordingly, a large number of event extraction systems have been developed. Most such systems, however, have been developed for specific tasks and/or incorporated task specific settings, making their application to new corpora and tasks problematic without modification of the systems themselves. There is thus a need for event extraction systems that can achieve high levels of accuracy when applied to corpora in new domains, without the need for exhaustive tuning or modification, whilst retaining competitive levels of performance. Results We have enhanced our state-of-the-art event extraction system, EventMine, to alleviate the need for task-specific tuning. Task-specific details are specified in a configuration file, while extensive task-specific parameter tuning is avoided through the integration of a weighting method, a covariate shift method, and their combination. The task-specific configuration and weighting method have been employed within the context of two different sub-tasks of BioNLP shared task 2013, i.e. Cancer Genetics (CG) and Pathway Curation (PC), removing the need to modify the system specifically for each task. With minimal task specific configuration and tuning, EventMine achieved the 1st place in the PC task, and 2nd in the CG, achieving the highest recall for both tasks. The system has been further enhanced following the shared task by incorporating the covariate shift method and entity generalisations based on the task definitions, leading to further performance improvements. Conclusions We have shown that it is possible to apply a state-of-the-art event extraction system to new tasks with high levels of performance, without having to modify the system internally. Both covariate shift and weighting methods are useful in facilitating the production of high recall systems

  3. Coreference based event-argument relation extraction on biomedical text

    PubMed Central

    2011-01-01

    This paper presents a new approach to exploit coreference information for extracting event-argument (E-A) relations from biomedical documents. This approach has two advantages: (1) it can extract a large number of valuable E-A relations based on the concept of salience in discourse; (2) it enables us to identify E-A relations over sentence boundaries (cross-links) using transitivity of coreference relations. We propose two coreference-based models: a pipeline based on Support Vector Machine (SVM) classifiers, and a joint Markov Logic Network (MLN). We show the effectiveness of these models on a biomedical event corpus. Both models outperform the systems that do not use coreference information. When the two proposed models are compared to each other, joint MLN outperforms pipeline SVM with gold coreference information. PMID:22166257

  4. Extraction of Stride Events From Gait Accelerometry During Treadmill Walking

    PubMed Central

    Lowry, Kristin A.; Bellanca, Jennica; Perera, Subashan; Redfern, Mark S.; Brach, Jennifer S.

    2016-01-01

    Objective: evaluating stride events can be valuable for understanding the changes in walking due to aging and neurological diseases. However, creating the time series necessary for this analysis can be cumbersome. In particular, finding heel contact and toe-off events which define the gait cycles accurately are difficult. Method: we proposed a method to extract stride cycle events from tri-axial accelerometry signals. We validated our method via data collected from 14 healthy controls, 10 participants with Parkinson’s disease, and 11 participants with peripheral neuropathy. All participants walked at self-selected comfortable and reduced speeds on a computer-controlled treadmill. Gait accelerometry signals were captured via a tri-axial accelerometer positioned over the L3 segment of the lumbar spine. Motion capture data were also collected and served as the comparison method. Results: our analysis of the accelerometry data showed that the proposed methodology was able to accurately extract heel and toe-contact events from both feet. We used t-tests, analysis of variance (ANOVA) and mixed models to summarize results and make comparisons. Mean gait cycle intervals were the same as those derived from motion capture, and cycle-to-cycle variability measures were within 1.5%. Subject group differences could be similarly identified using measures with the two methods. Conclusions: a simple tri-axial acceleromter accompanied by a signal processing algorithm can be used to capture stride events. Clinical impact: the proposed algorithm enables the assessment of stride events during treadmill walking, and is the first step toward the assessment of stride events using tri-axial accelerometers in real-life settings. PMID:27088063

  5. Extracting protein interactions from text with the unified AkaneRE event extraction system.

    PubMed

    Saetre, Rune; Yoshida, Kazuhiro; Miwa, Makoto; Matsuzaki, Takuya; Kano, Yoshinobu; Tsujii, Jun'ichi

    2010-01-01

    Currently, relation extraction (RE) and event extraction (EE) are the two main streams of biological information extraction. In 2009, the majority of these RE and EE research efforts were centered around the BioCreative II.5 Protein-Protein Interaction (PPI) challenge and the "BioNLP event extraction shared task." Although these challenges took somewhat different approaches, they share the same ultimate goal of extracting bio-knowledge from the literature. This paper compares the two challenge task definitions, and presents a unified system that was successfully applied in both these and several other PPI extraction task settings. The AkaneRE system has three parts: A core engine for RE, a pool of modules for specific solutions, and a configuration language to adapt the system to different tasks. The core engine is based on machine learning, using either Support Vector Machines or Statistical Classifiers and features extracted from given training data. The specific modules solve tasks like sentence boundary detection, tokenization, stemming, part-of-speech tagging, parsing, named entity recognition, generation of potential relations, generation of machine learning features for each relation, and finally, assignment of confidence scores and ranking of candidate relations. With these components, the AkaneRE system produces state-of-the-art results, and the system is freely available for academic purposes at http://www-tsujii.is.s.u-tokyo.ac.jp/satre/akane/. PMID:20671316

  6. Waves associated to COMPLEX EVENTS observed by STEREO

    NASA Astrophysics Data System (ADS)

    Siu Tapia, A. L.; Blanco-Cano, X.; Kajdic, P.; Aguilar-Rodriguez, E.; Russell, C. T.; Jian, L. K.; Luhmann, J. G.

    2012-12-01

    Complex Events are formed by two or more large-scale solar wind structures which interact in space. Typical cases are interactions of: (i) a Magnetic Cloud/Interplanetary Coronal Mass Ejection (MC/ICME) with another MC/ICME transient; and (ii) an ICME followed by a Stream Interaction Region (SIR). Complex Events are of importance for space weather studies and studying them can enhance our understanding of collisionless plasma physics. Some of these structures can produce or enhance southward magnetic fields, a key factor in geomagnetic storm generation. Using data from the STEREO mission during the years 2006-2011, we found 17 Complex Events preceded by a shock wave. We use magnetic field and plasma data to study the micro-scale structure of the shocks, and the waves associated to these shocks and within Complex Events structures. To determine wave characteristics we perform Power Spectra and Minimum Variance Analysis. We also use PLASTIC WAP protons data to study foreshock extensions and the relationship between Complex Regions and particle acceleration to suprathermal energies.

  7. The complex correspondence between families and collisional events

    NASA Astrophysics Data System (ADS)

    Milani Comparetti, Andrea

    2015-08-01

    Asteroid families are identified as statistically significant concentrations of asteroids in the space of proper elements. The purpose of family classifications is meant to be the identification of the largest collisional events occurred during the history of the asteroid main belt. However, are the families as found in 1-1 correspondence with ancient collisional events? A recent analysis of larger classifications, based on larger and more accurate datasets of proper elements, indicates that this is not the case. There are multiple cratering events on the same parent body. There are collisional families split into two by the YORP effect. There are subfamilies arising from secondary collisions after the one forming a larger family, and this is not limited to recent events. There are families overlapping in proper elements space but with composition incompatible with a common parent body. There are cases not yet understood, but pointing to a complex collisional history. In total at least 10 cases of complex correpondence between families and collisional events have been identified, more are suspected but not yet supported by enough evidence. The disentagling of these complex collisional histories is an essential step towards the understanding of the asteroid collisional evolution.

  8. Extreme events and natural hazards: The complexity perspective

    NASA Astrophysics Data System (ADS)

    Schultz, Colin

    2012-10-01

    Advanced societies have become quite proficient at defending against moderate-size earthquakes, hurricanes, floods, or other natural assaults. What still pose a significant threat, however, are the unknowns, the extremes, the natural phenomena encompassed by the upper tail of the probability distribution. Alongside the large or powerful events, truly extreme natural disasters are those that tie different systems together: an earthquake that causes a tsunami, which leads to flooding, which takes down a nuclear reactor. In the geophysical monograph Extreme Events and Natural Hazards: The Complexity Perspective, editors A. Surjalal Sharma, Armin Bunde, Vijay P. Dimro, and Daniel N. Baker present a lens through which such multidisciplinary phenomena can be understood. In this interview, Eos talks to Sharma about complexity science, predicting extreme events and natural hazards, and the push for "big data."

  9. Complex events in a fault model with interacting asperities

    NASA Astrophysics Data System (ADS)

    Dragoni, Michele; Tallarico, Andrea

    2016-08-01

    The dynamics of a fault with heterogeneous friction is studied by employing a discrete fault model with two asperities of different strengths. The average values of stress, friction and slip on each asperity are considered and the state of the fault is described by the slip deficits of the asperities as functions of time. The fault has three different slipping modes, corresponding to the asperities slipping one at a time or simultaneously. Any seismic event produced by the fault is a sequence of n slipping modes. According to initial conditions, seismic events can be different sequences of slipping modes, implying different moment rates and seismic moments. Each event can be represented geometrically in the state space by an orbit that is the union of n damped Lissajous curves. We focus our interest on events that are sequences of two or more slipping modes: they show a complex stress interchange between the asperities and a complex temporal pattern of slip rate. The initial stress distribution producing these events is not uniform on the fault. We calculate the stress drop, the moment rate and the frequency spectrum of the events, showing how these quantities depend on initial conditions. These events have the greatest seismic moments that can be produced by fault slip. As an example, we model the moment rate of the 1992 Landers, California, earthquake that can be described as the consecutive failure of two asperities, one of which has a double strength than the other, and evaluate the evolution of stress distribution on the fault during the event.

  10. Deep Fusion of Multiple Semantic Cues for Complex Event Recognition.

    PubMed

    Zhang, Xishan; Zhang, Hanwang; Zhang, Yongdong; Yang, Yang; Wang, Meng; Luan, Huanbo; Li, Jintao; Chua, Tat-Seng

    2016-03-01

    We present a deep learning strategy to fuse multiple semantic cues for complex event recognition. In particular, we tackle the recognition task by answering how to jointly analyze human actions (who is doing what), objects (what), and scenes (where). First, each type of semantic features (e.g., human action trajectories) is fed into a corresponding multi-layer feature abstraction pathway, followed by a fusion layer connecting all the different pathways. Second, the correlations of how the semantic cues interacting with each other are learned in an unsupervised cross-modality autoencoder fashion. Finally, by fine-tuning a large-margin objective deployed on this deep architecture, we are able to answer the question on how the semantic cues of who, what, and where compose a complex event. As compared with the traditional feature fusion methods (e.g., various early or late strategies), our method jointly learns the essential higher level features that are most effective for fusion and recognition. We perform extensive experiments on two real-world complex event video benchmarks, MED'11 and CCV, and demonstrate that our method outperforms the best published results by 21% and 11%, respectively, on an event recognition task. PMID:26780785

  11. Finding the Cause: Verbal Framing Helps Children Extract Causal Evidence Embedded in a Complex Scene

    ERIC Educational Resources Information Center

    Butler, Lucas P.; Markman, Ellen M.

    2012-01-01

    In making causal inferences, children must both identify a causal problem and selectively attend to meaningful evidence. Four experiments demonstrate that verbally framing an event ("Which animals make Lion laugh?") helps 4-year-olds extract evidence from a complex scene to make accurate causal inferences. Whereas framing was unnecessary when…

  12. Consolidation of Complex Events via Reinstatement in Posterior Cingulate Cortex.

    PubMed

    Bird, Chris M; Keidel, James L; Ing, Leslie P; Horner, Aidan J; Burgess, Neil

    2015-10-28

    It is well-established that active rehearsal increases the efficacy of memory consolidation. It is also known that complex events are interpreted with reference to prior knowledge. However, comparatively little attention has been given to the neural underpinnings of these effects. In healthy adults humans, we investigated the impact of effortful, active rehearsal on memory for events by showing people several short video clips and then asking them to recall these clips, either aloud (Experiment 1) or silently while in an MRI scanner (Experiment 2). In both experiments, actively rehearsed clips were remembered in far greater detail than unrehearsed clips when tested a week later. In Experiment 1, highly similar descriptions of events were produced across retrieval trials, suggesting a degree of semanticization of the memories had taken place. In Experiment 2, spatial patterns of BOLD signal in medial temporal and posterior midline regions were correlated when encoding and rehearsing the same video. Moreover, the strength of this correlation in the posterior cingulate predicted the amount of information subsequently recalled. This is likely to reflect a strengthening of the representation of the video's content. We argue that these representations combine both new episodic information and stored semantic knowledge (or "schemas"). We therefore suggest that posterior midline structures aid consolidation by reinstating and strengthening the associations between episodic details and more generic schematic information. This leads to the creation of coherent memory representations of lifelike, complex events that are resistant to forgetting, but somewhat inflexible and semantic-like in nature. PMID:26511235

  13. Simulating an Extreme Wind Event in a Topographically Complex Region

    NASA Astrophysics Data System (ADS)

    Lennard, Christopher

    2014-07-01

    Complex topography modifies local weather characteristics such as air temperature, rainfall and airflow within a larger regional extent. The Cape Peninsula around Cape Town, South Africa, is a complex topographical feature responsible for the modification of rainfall and wind fields largely downstream of the Peninsula. During the passage of a cold front on 2 October 2002, an extreme wind event associated with tornado-like damage occurred in the suburb of Manenberg, however synoptic conditions did not indicate convective activity typically associated with a tornado. A numerical regional climate model was operated at very high horizontal resolution (500 m) to investigate the dynamics of the event. The model simulated an interaction between the topography of the peninsula and an airflow direction change associated with the passage of the cold front. A small region of cyclonic circulation was simulated over Manenberg that was embedded in an area of negative vorticity and a leeward gravity wave. The feature lasted 14 min and moved in a north to south direction. Vertically, it was not evident above 220 m. The model assessment describes this event as a shallow but intense cyclonic vortex generated in the lee of the peninsula through an interaction between the peninsula and a change in wind direction as the cold front made landfall. The model did not simulate wind speeds associated with the observed damage suggesting that the horizontal grid resolution ought to be at the scale of the event to more completely understand such microscale airflow phenomena.

  14. Extraction of spatio-temporal information of earthquake event based on semantic technology

    NASA Astrophysics Data System (ADS)

    Fan, Hong; Guo, Dan; Li, Huaiyuan

    2015-12-01

    In this paper a web information extraction method is presented which identifies a variety of thematic events utilizing the event knowledge framework derived from text training, and then further uses the syntactic analysis to extract the event key information. The method which combines the text semantic information and domain knowledge of the event makes the extraction of information people interested more accurate. In this paper, web based earthquake news extraction is taken as an example. The paper firstly briefs the overall approaches, and then details the key algorithm and experiments of seismic events extraction. Finally, this paper conducts accuracy analysis and evaluation experiments which demonstrate that the proposed method is a promising way of hot events mining.

  15. Polyhydroxyflavones as extractants. Communication 7. Solvent extraction of europrium complexes with morin from alkaline media

    SciTech Connect

    Blank, A.B.

    1985-09-01

    This paper studies the analytical application of europium (III)-morin complex which is formed in alkaline medium and has an intense color. The extent of europium extraction was determined by adding to the extract a morin solution in isoamyl alcohol in a 50-100-fold excess with respect to europium. The dependence of the optical density of the extracts on the ph in the system europium (III)-morin-water-organic solvent for different excesses of the reagent is shown: this indicates formation of two extractable complexes, one being dominant in the pH range 4-7, the other at pH greater than or equal to 8.5. The extraction of the europium (III)-morin complex from alkaline solution is used for direct extraction-photometric determination of europium(III) in compounds of elements having amphoteric properties or forming amines (Zns, Mo0/sub 3/).

  16. Consolidation of Complex Events via Reinstatement in Posterior Cingulate Cortex

    PubMed Central

    Keidel, James L.; Ing, Leslie P.; Horner, Aidan J.

    2015-01-01

    It is well-established that active rehearsal increases the efficacy of memory consolidation. It is also known that complex events are interpreted with reference to prior knowledge. However, comparatively little attention has been given to the neural underpinnings of these effects. In healthy adults humans, we investigated the impact of effortful, active rehearsal on memory for events by showing people several short video clips and then asking them to recall these clips, either aloud (Experiment 1) or silently while in an MRI scanner (Experiment 2). In both experiments, actively rehearsed clips were remembered in far greater detail than unrehearsed clips when tested a week later. In Experiment 1, highly similar descriptions of events were produced across retrieval trials, suggesting a degree of semanticization of the memories had taken place. In Experiment 2, spatial patterns of BOLD signal in medial temporal and posterior midline regions were correlated when encoding and rehearsing the same video. Moreover, the strength of this correlation in the posterior cingulate predicted the amount of information subsequently recalled. This is likely to reflect a strengthening of the representation of the video's content. We argue that these representations combine both new episodic information and stored semantic knowledge (or “schemas”). We therefore suggest that posterior midline structures aid consolidation by reinstating and strengthening the associations between episodic details and more generic schematic information. This leads to the creation of coherent memory representations of lifelike, complex events that are resistant to forgetting, but somewhat inflexible and semantic-like in nature. SIGNIFICANCE STATEMENT Memories are strengthened via consolidation. We investigated memory for lifelike events using video clips and showed that rehearsing their content dramatically boosts memory consolidation. Using MRI scanning, we measured patterns of brain activity while

  17. Extracting, Tracking, and Visualizing Magnetic Flux Vortices in 3D Complex-Valued Superconductor Simulation Data.

    PubMed

    Guo, Hanqi; Phillips, Carolyn L; Peterka, Tom; Karpeyev, Dmitry; Glatz, Andreas

    2016-01-01

    We propose a method for the vortex extraction and tracking of superconducting magnetic flux vortices for both structured and unstructured mesh data. In the Ginzburg-Landau theory, magnetic flux vortices are well-defined features in a complex-valued order parameter field, and their dynamics determine electromagnetic properties in type-II superconductors. Our method represents each vortex line (a 1D curve embedded in 3D space) as a connected graph extracted from the discretized field in both space and time. For a time-varying discrete dataset, our vortex extraction and tracking method is as accurate as the data discretization. We then apply 3D visualization and 2D event diagrams to the extraction and tracking results to help scientists understand vortex dynamics and macroscale superconductor behavior in greater detail than previously possible. PMID:26529730

  18. Modeling of ion complexation and extraction using substructural molecular fragments

    PubMed

    Solov'ev; Varnek; Wipff

    2000-05-01

    A substructural molecular fragment (SMF) method has been developed to model the relationships between the structure of organic molecules and their thermodynamic parameters of complexation or extraction. The method is based on the splitting of a molecule into fragments, and on calculations of their contributions to a given property. It uses two types of fragments: atom/bond sequences and "augmented atoms" (atoms with their nearest neighbors). The SMF approach is tested on physical properties of C2-C9 alkanes (boiling point, molar volume, molar refraction, heat of vaporization, surface tension, melting point, critical temperature, and critical pressures) and on octanol/water partition coefficients. Then, it is applied to the assessment of (i) complexation stability constants of alkali cations with crown ethers and phosphoryl-containing podands, and of beta-cyclodextrins with mono- and 1,4-disubstituted benzenes, and (ii) solvent extraction constants for the complexes of uranyl cation by phosphoryl-containing ligands. PMID:10850791

  19. Knowledge-Driven Event Extraction in Russian: Corpus-Based Linguistic Resources

    PubMed Central

    Solovyev, Valery; Ivanov, Vladimir

    2016-01-01

    Automatic event extraction form text is an important step in knowledge acquisition and knowledge base population. Manual work in development of extraction system is indispensable either in corpus annotation or in vocabularies and pattern creation for a knowledge-based system. Recent works have been focused on adaptation of existing system (for extraction from English texts) to new domains. Event extraction in other languages was not studied due to the lack of resources and algorithms necessary for natural language processing. In this paper we define a set of linguistic resources that are necessary in development of a knowledge-based event extraction system in Russian: a vocabulary of subordination models, a vocabulary of event triggers, and a vocabulary of Frame Elements that are basic building blocks for semantic patterns. We propose a set of methods for creation of such vocabularies in Russian and other languages using Google Books NGram Corpus. The methods are evaluated in development of event extraction system for Russian. PMID:26955386

  20. Knowledge-Driven Event Extraction in Russian: Corpus-Based Linguistic Resources.

    PubMed

    Solovyev, Valery; Ivanov, Vladimir

    2016-01-01

    Automatic event extraction form text is an important step in knowledge acquisition and knowledge base population. Manual work in development of extraction system is indispensable either in corpus annotation or in vocabularies and pattern creation for a knowledge-based system. Recent works have been focused on adaptation of existing system (for extraction from English texts) to new domains. Event extraction in other languages was not studied due to the lack of resources and algorithms necessary for natural language processing. In this paper we define a set of linguistic resources that are necessary in development of a knowledge-based event extraction system in Russian: a vocabulary of subordination models, a vocabulary of event triggers, and a vocabulary of Frame Elements that are basic building blocks for semantic patterns. We propose a set of methods for creation of such vocabularies in Russian and other languages using Google Books NGram Corpus. The methods are evaluated in development of event extraction system for Russian. PMID:26955386

  1. Optimizing graph-based patterns to extract biomedical events from the literature.

    PubMed

    Liu, Haibin; Verspoor, Karin; Comeau, Donald C; MacKinlay, Andrew D; Wilbur, W

    2015-01-01

    IN BIONLP-ST 2013: We participated in the BioNLP 2013 shared tasks on event extraction. Our extraction method is based on the search for an approximate subgraph isomorphism between key context dependencies of events and graphs of input sentences. Our system was able to address both the GENIA (GE) task focusing on 13 molecular biology related event types and the Cancer Genetics (CG) task targeting a challenging group of 40 cancer biology related event types with varying arguments concerning 18 kinds of biological entities. In addition to adapting our system to the two tasks, we also attempted to integrate semantics into the graph matching scheme using a distributional similarity model for more events, and evaluated the event extraction impact of using paths of all possible lengths as key context dependencies beyond using only the shortest paths in our system. We achieved a 46.38% F-score in the CG task (ranking 3rd) and a 48.93% F-score in the GE task (ranking 4th). AFTER BIONLP-ST 2013: We explored three ways to further extend our event extraction system in our previously published work: (1) We allow non-essential nodes to be skipped, and incorporated a node skipping penalty into the subgraph distance function of our approximate subgraph matching algorithm. (2) Instead of assigning a unified subgraph distance threshold to all patterns of an event type, we learned a customized threshold for each pattern. (3) We implemented the well-known Empirical Risk Minimization (ERM) principle to optimize the event pattern set by balancing prediction errors on training data against regularization. When evaluated on the official GE task test data, these extensions help to improve the extraction precision from 62% to 65%. However, the overall F-score stays equivalent to the previous performance due to a 1% drop in recall. PMID:26551594

  2. Optimizing graph-based patterns to extract biomedical events from the literature

    PubMed Central

    2015-01-01

    In BioNLP-ST 2013 We participated in the BioNLP 2013 shared tasks on event extraction. Our extraction method is based on the search for an approximate subgraph isomorphism between key context dependencies of events and graphs of input sentences. Our system was able to address both the GENIA (GE) task focusing on 13 molecular biology related event types and the Cancer Genetics (CG) task targeting a challenging group of 40 cancer biology related event types with varying arguments concerning 18 kinds of biological entities. In addition to adapting our system to the two tasks, we also attempted to integrate semantics into the graph matching scheme using a distributional similarity model for more events, and evaluated the event extraction impact of using paths of all possible lengths as key context dependencies beyond using only the shortest paths in our system. We achieved a 46.38% F-score in the CG task (ranking 3rd) and a 48.93% F-score in the GE task (ranking 4th). After BioNLP-ST 2013 We explored three ways to further extend our event extraction system in our previously published work: (1) We allow non-essential nodes to be skipped, and incorporated a node skipping penalty into the subgraph distance function of our approximate subgraph matching algorithm. (2) Instead of assigning a unified subgraph distance threshold to all patterns of an event type, we learned a customized threshold for each pattern. (3) We implemented the well-known Empirical Risk Minimization (ERM) principle to optimize the event pattern set by balancing prediction errors on training data against regularization. When evaluated on the official GE task test data, these extensions help to improve the extraction precision from 62% to 65%. However, the overall F-score stays equivalent to the previous performance due to a 1% drop in recall. PMID:26551594

  3. Ion flotation and solvent extraction of ferric thiocyanate complexes

    SciTech Connect

    Jurkiewicz, K.

    1987-12-01

    The influence of thiocyanate and accompanying mineral acids concentration on the effectiveness of Fe(III) ion flotation, Fe(III) precipitation in cetyltrimethylammonium ferric-thiocyanate form (as sublate), and Fe(III) extraction using ethyl acetate was studied. The effectiveness of these processes improves with the extent of Fe(III) complexation by thiocyanates. In the presence of acids, flotation and precipitation are increased as follows: HClO/sub 4/ < HCl < HNO/sub 3/ < H/sub 2/SO/sub 4/. The position of H/sub 3/PO/sub 4/ in this series changes with changing thiocyanate concentration. Extraction effectiveness is increased in the series: H/sub 3/PO/sub 4/ < H/sub 2/SO/sub 4/ < HNO/sub 3/, HClO/sub 4/, HCl. The following points are discussed: (a) the influence of acid anions competing with thiocyanate anions in Fe(III) complexation; (b) the influence of the competition between acid anions and complex ferric-thiocyanate anions in sublate formation; (c) the influence of hydrogen ion concentration increase in thiocyanate medium on the results of Fe(III) flotation, precipitation, and extraction; and (d) the influence of anion affinity for a collector on the solution surface properties and on Fe(III) flotation.

  4. Large-scale event extraction from literature with multi-level gene normalization.

    PubMed

    Van Landeghem, Sofie; Björne, Jari; Wei, Chih-Hsuan; Hakala, Kai; Pyysalo, Sampo; Ananiadou, Sophia; Kao, Hung-Yu; Lu, Zhiyong; Salakoski, Tapio; Van de Peer, Yves; Ginter, Filip

    2013-01-01

    Text mining for the life sciences aims to aid database curation, knowledge summarization and information retrieval through the automated processing of biomedical texts. To provide comprehensive coverage and enable full integration with existing biomolecular database records, it is crucial that text mining tools scale up to millions of articles and that their analyses can be unambiguously linked to information recorded in resources such as UniProt, KEGG, BioGRID and NCBI databases. In this study, we investigate how fully automated text mining of complex biomolecular events can be augmented with a normalization strategy that identifies biological concepts in text, mapping them to identifiers at varying levels of granularity, ranging from canonicalized symbols to unique gene and proteins and broad gene families. To this end, we have combined two state-of-the-art text mining components, previously evaluated on two community-wide challenges, and have extended and improved upon these methods by exploiting their complementary nature. Using these systems, we perform normalization and event extraction to create a large-scale resource that is publicly available, unique in semantic scope, and covers all 21.9 million PubMed abstracts and 460 thousand PubMed Central open access full-text articles. This dataset contains 40 million biomolecular events involving 76 million gene/protein mentions, linked to 122 thousand distinct genes from 5032 species across the full taxonomic tree. Detailed evaluations and analyses reveal promising results for application of this data in database and pathway curation efforts. The main software components used in this study are released under an open-source license. Further, the resulting dataset is freely accessible through a novel API, providing programmatic and customized access (http://www.evexdb.org/api/v001/). Finally, to allow for large-scale bioinformatic analyses, the entire resource is available for bulk download from http

  5. Large-Scale Event Extraction from Literature with Multi-Level Gene Normalization

    PubMed Central

    Wei, Chih-Hsuan; Hakala, Kai; Pyysalo, Sampo; Ananiadou, Sophia; Kao, Hung-Yu; Lu, Zhiyong; Salakoski, Tapio; Van de Peer, Yves; Ginter, Filip

    2013-01-01

    Text mining for the life sciences aims to aid database curation, knowledge summarization and information retrieval through the automated processing of biomedical texts. To provide comprehensive coverage and enable full integration with existing biomolecular database records, it is crucial that text mining tools scale up to millions of articles and that their analyses can be unambiguously linked to information recorded in resources such as UniProt, KEGG, BioGRID and NCBI databases. In this study, we investigate how fully automated text mining of complex biomolecular events can be augmented with a normalization strategy that identifies biological concepts in text, mapping them to identifiers at varying levels of granularity, ranging from canonicalized symbols to unique gene and proteins and broad gene families. To this end, we have combined two state-of-the-art text mining components, previously evaluated on two community-wide challenges, and have extended and improved upon these methods by exploiting their complementary nature. Using these systems, we perform normalization and event extraction to create a large-scale resource that is publicly available, unique in semantic scope, and covers all 21.9 million PubMed abstracts and 460 thousand PubMed Central open access full-text articles. This dataset contains 40 million biomolecular events involving 76 million gene/protein mentions, linked to 122 thousand distinct genes from 5032 species across the full taxonomic tree. Detailed evaluations and analyses reveal promising results for application of this data in database and pathway curation efforts. The main software components used in this study are released under an open-source license. Further, the resulting dataset is freely accessible through a novel API, providing programmatic and customized access (http://www.evexdb.org/api/v001/). Finally, to allow for large-scale bioinformatic analyses, the entire resource is available for bulk download from http

  6. Complex Dynamic Scene Perception: Effects of Attentional Set on Perceiving Single and Multiple Event Types

    ERIC Educational Resources Information Center

    Sanocki, Thomas; Sulman, Noah

    2013-01-01

    Three experiments measured the efficiency of monitoring complex scenes composed of changing objects, or events. All events lasted about 4 s, but in a given block of trials, could be of a single type (single task) or of multiple types (multitask, with a total of four event types). Overall accuracy of detecting target events amid distractors was…

  7. A pipeline to extract drug-adverse event pairs from multiple data sources

    PubMed Central

    2014-01-01

    Background Pharmacovigilance aims to uncover and understand harmful side-effects of drugs, termed adverse events (AEs). Although the current process of pharmacovigilance is very systematic, the increasing amount of information available in specialized health-related websites as well as the exponential growth in medical literature presents a unique opportunity to supplement traditional adverse event gathering mechanisms with new-age ones. Method We present a semi-automated pipeline to extract associations between drugs and side effects from traditional structured adverse event databases, enhanced by potential drug-adverse event pairs mined from user-comments from health-related websites and MEDLINE abstracts. The pipeline was tested using a set of 12 drugs representative of two previous studies of adverse event extraction from health-related websites and MEDLINE abstracts. Results Testing the pipeline shows that mining non-traditional sources helps substantiate the adverse event databases. The non-traditional sources not only contain the known AEs, but also suggest some unreported AEs for drugs which can then be analyzed further. Conclusion A semi-automated pipeline to extract the AE pairs from adverse event databases as well as potential AE pairs from non-traditional sources such as text from MEDLINE abstracts and user-comments from health-related websites is presented. PMID:24559132

  8. Sex Differences in Infants' Ability to Represent Complex Event Sequences

    ERIC Educational Resources Information Center

    Schweinle, Amy; Wilcox, Teresa

    2004-01-01

    Prior research suggests that when very simple event sequences are used, 4.5-month-olds demonstrate the ability to individuate objects based on the continuity or disruption of their speed of motion (Wilcox & Schweinle, 2003). However, infants demonstrate their ability to individuate objects in an event-monitoring task (i.e., infants must keep track…

  9. Extreme events in multilayer, interdependent complex networks and control

    NASA Astrophysics Data System (ADS)

    Chen, Yu-Zhong; Huang, Zi-Gang; Zhang, Hai-Feng; Eisenberg, Daniel; Seager, Thomas P.; Lai, Ying-Cheng

    2015-11-01

    We investigate the emergence of extreme events in interdependent networks. We introduce an inter-layer traffic resource competing mechanism to account for the limited capacity associated with distinct network layers. A striking finding is that, when the number of network layers and/or the overlap among the layers are increased, extreme events can emerge in a cascading manner on a global scale. Asymptotically, there are two stable absorption states: a state free of extreme events and a state of full of extreme events, and the transition between them is abrupt. Our results indicate that internal interactions in the multiplex system can yield qualitatively distinct phenomena associated with extreme events that do not occur for independent network layers. An implication is that, e.g., public resource competitions among different service providers can lead to a higher resource requirement than naively expected. We derive an analytical theory to understand the emergence of global-scale extreme events based on the concept of effective betweenness. We also articulate a cost-effective control scheme through increasing the capacity of very few hubs to suppress the cascading process of extreme events so as to protect the entire multi-layer infrastructure against global-scale breakdown.

  10. Extractive summarization using complex networks and syntactic dependency

    NASA Astrophysics Data System (ADS)

    Amancio, Diego R.; Nunes, Maria G. V.; Oliveira, Osvaldo N.; Costa, Luciano da F.

    2012-02-01

    The realization that statistical physics methods can be applied to analyze written texts represented as complex networks has led to several developments in natural language processing, including automatic summarization and evaluation of machine translation. Most importantly, so far only a few metrics of complex networks have been used and therefore there is ample opportunity to enhance the statistics-based methods as new measures of network topology and dynamics are created. In this paper, we employ for the first time the metrics betweenness, vulnerability and diversity to analyze written texts in Brazilian Portuguese. Using strategies based on diversity metrics, a better performance in automatic summarization is achieved in comparison to previous work employing complex networks. With an optimized method the Rouge score (an automatic evaluation method used in summarization) was 0.5089, which is the best value ever achieved for an extractive summarizer with statistical methods based on complex networks for Brazilian Portuguese. Furthermore, the diversity metric can detect keywords with high precision, which is why we believe it is suitable to produce good summaries. It is also shown that incorporating linguistic knowledge through a syntactic parser does enhance the performance of the automatic summarizers, as expected, but the increase in the Rouge score is only minor. These results reinforce the suitability of complex network methods for improving automatic summarizers in particular, and treating text in general.

  11. Automatically Extracting Information Needs from Complex Clinical Questions

    PubMed Central

    Cao, Yong-gang; Cimino, James J; Ely, John; Yu, Hong

    2010-01-01

    Objective Clinicians pose complex clinical questions when seeing patients, and identifying the answers to those questions in a timely manner helps improve the quality of patient care. We report here on two natural language processing models, namely, automatic topic assignment and keyword identification, that together automatically and effectively extract information needs from ad hoc clinical questions. Our study is motivated in the context of developing the larger clinical question answering system AskHERMES (Help clinicians to Extract and aRrticulate Multimedia information for answering clinical quEstionS). Design and Measurements We developed supervised machine-learning systems to automatically assign predefined general categories (e.g., etiology, procedure, and diagnosis) to a question. We also explored both supervised and unsupervised systems to automatically identify keywords that capture the main content of the question. Results We evaluated our systems on 4,654 annotated clinical questions that were collected in practice. We achieved an F1 score of 76.0% for the task of general topic classification and 58.0% for keyword extraction. Our systems have been implemented into the larger question answering system AskHERMES. Our error analyses suggested that inconsistent annotation in our training data have hurt both question analysis tasks. Conclusion Our systems, available at http://www.askhermes.org, can automatically extract information needs from both short (the number of word tokens <20) and long questions (the number of word tokens >20), and from both well-structured and ill-formed questions. We speculate that the performance of general topic classification and keyword extraction can be further improved if consistently annotated data are made available. PMID:20670693

  12. Extracting insights from the shape of complex data using topology

    PubMed Central

    Lum, P. Y.; Singh, G.; Lehman, A.; Ishkanov, T.; Vejdemo-Johansson, M.; Alagappan, M.; Carlsson, J.; Carlsson, G.

    2013-01-01

    This paper applies topological methods to study complex high dimensional data sets by extracting shapes (patterns) and obtaining insights about them. Our method combines the best features of existing standard methodologies such as principal component and cluster analyses to provide a geometric representation of complex data sets. Through this hybrid method, we often find subgroups in data sets that traditional methodologies fail to find. Our method also permits the analysis of individual data sets as well as the analysis of relationships between related data sets. We illustrate the use of our method by applying it to three very different kinds of data, namely gene expression from breast tumors, voting data from the United States House of Representatives and player performance data from the NBA, in each case finding stratifications of the data which are more refined than those produced by standard methods. PMID:23393618

  13. Self-Complexity, Daily Events, and Perceived Quality of Life.

    ERIC Educational Resources Information Center

    Kardash, CarolAnne M.; Okun, Morris A.

    Recent research has demonstrated that self-cognitions can play an important role in physical and emotional well-being. One important aspect of self-cognition concerns the complexity of self-representations. This study tested the hypothesis that self-complexity, as assessed by Linville's self-trait sorting task, would moderate the effects of…

  14. Complexation-induced supramolecular assembly drives metal-ion extraction.

    PubMed

    Ellis, Ross J; Meridiano, Yannick; Muller, Julie; Berthon, Laurence; Guilbaud, Philippe; Zorz, Nicole; Antonio, Mark R; Demars, Thomas; Zemb, Thomas

    2014-09-26

    Combining experiment with theory reveals the role of self-assembly and complexation in metal-ion transfer through the water-oil interface. The coordinating metal salt Eu(NO3)3 was extracted from water into oil by a lipophilic neutral amphiphile. Molecular dynamics simulations were coupled to experimental spectroscopic and X-ray scattering techniques to investigate how local coordination interactions between the metal ion and ligands in the organic phase combine with long-range interactions to produce spontaneous changes in the solvent microstructure. Extraction of the Eu(3+)-3(NO3(-)) ion pairs involves incorporation of the "hard" metal complex into the core of "soft" aggregates. This seeds the formation of reverse micelles that draw the water and "free" amphiphile into nanoscale hydrophilic domains. The reverse micelles interact through attractive van der Waals interactions and coalesce into rod-shaped polynuclear Eu(III) -containing aggregates with metal centers bridged by nitrate. These preorganized hydrophilic domains, containing high densities of O-donor ligands and anions, provide improved Eu(III) solvation environments that help drive interfacial transfer, as is reflected by the increasing Eu(III) partitioning ratios (oil/aqueous) despite the organic phase approaching saturation. For the first time, this multiscale approach links metal-ion coordination with nanoscale structure to reveal the free-energy balance that drives the phase transfer of neutral metal salts. PMID:25169678

  15. Evidence for Complex Molecular Architectures for Solvent-Extracted Lignins

    SciTech Connect

    Rials, Timothy G; Urban, Volker S; Langan, Paul

    2012-01-01

    Lignin, an abundant, naturally occurring biopolymer, is often considered 'waste' and used as a simple fuel source in the paper-making process. However, lignin has emerged as a promising renewable resource for engineering materials, such as carbon fibers. Unfortunately, the molecular architecture of lignin (in vivo and extracted) is still elusive, with numerous conflicting reports in the literature, and knowledge of this structure is extremely important, not only for materials technologies, but also for production of biofuels such as cellulosic ethanol due to biomass recalcitrance. As such, the molecular structures of solvent-extracted (sulfur-free) lignins, which have been modified using various acyl chlorides, have been probed using small-angle X-ray (SAXS) and neutron (SANS) scattering in tetrahydrofuran (THF) solution along with hydrodynamic characterization using dilute solution viscometry and gel permeation chromatography (GPC) in THF. Mass spectrometry shows an absolute molecular weight {approx}18-30 kDa ({approx}80-140 monomers), while GPC shows a relative molecular weight {approx}3 kDa. A linear styrene oligomer (2.5 kDa) was also analyzed in THF using SANS. Results clearly show that lignin molecular architectures are somewhat rigid and complex, ranging from nanogels to hyperbranched macromolecules, not linear oligomers or physical assemblies of oligomers, which is consistent with previously proposed delignification (extraction) mechanisms. Future characterization using the methods discussed here can be used to guide extraction processes as well as genetic engineering technologies to convert lignin into value added materials with the potential for high positive impact on global sustainability.

  16. Analyses Of Transient Events In Complex Valve and Feed Systems

    NASA Technical Reports Server (NTRS)

    Ahuja, Vineet; Hosangadi, Ashvin; Cavallo, Peter; Daines, Russell

    2005-01-01

    Valve systems in rocket propulsion systems and testing facilities are constantly subject to dynamic events resulting from the timing of valve motion leading to unsteady fluctuations in pressure and mass flow. Such events can also be accompanied by cavitation, resonance, system vibration leading to catastrophic failure. High-fidelity dynamic computational simulations of valve operation can yield important information of valve response to varying flow conditions. Prediction of transient behavior related to valve motion can serve as guidelines for valve scheduling, which is of crucial importance in engine operation and testing. In this paper, we present simulations of the diverse unsteady phenomena related to valve and feed systems that include valve stall, valve timing studies as well as cavitation instabilities in components utilized in the test loop.

  17. Scale invariance of temporal order discrimination using complex, naturalistic events

    PubMed Central

    Kwok, Sze Chai; Macaluso, Emiliano

    2015-01-01

    Recent demonstrations of scale invariance in cognitive domains prompted us to investigate whether a scale-free pattern might exist in retrieving the temporal order of events from episodic memory. We present four experiments using an encoding-retrieval paradigm with naturalistic stimuli (movies or video clips). Our studies show that temporal order judgement retrieval times were negatively correlated with the temporal separation between two events in the movie. This relation held, irrespective of whether temporal distances were on the order of tens of minutes (Exp 1−2) or just a few seconds (Exp 3−4). Using the SIMPLE model, we factored in the retention delays between encoding and retrieval (delays of 24 h, 15 min, 1.5–2.5 s, and 0.5 s for Exp 1–4, respectively) and computed a temporal similarity score for each trial. We found a positive relation between similarity and retrieval times; that is, the more temporally similar two events, the slower the retrieval of their temporal order. Using Bayesian analysis, we confirmed the equivalence of the RT/similarity relation across all experiments, which included a vast range of temporal distances and retention delays. These results provide evidence for scale invariance during the retrieval of temporal order of episodic memories. PMID:25909581

  18. Scale invariance of temporal order discrimination using complex, naturalistic events.

    PubMed

    Kwok, Sze Chai; Macaluso, Emiliano

    2015-07-01

    Recent demonstrations of scale invariance in cognitive domains prompted us to investigate whether a scale-free pattern might exist in retrieving the temporal order of events from episodic memory. We present four experiments using an encoding-retrieval paradigm with naturalistic stimuli (movies or video clips). Our studies show that temporal order judgement retrieval times were negatively correlated with the temporal separation between two events in the movie. This relation held, irrespective of whether temporal distances were on the order of tens of minutes (Exp 1-2) or just a few seconds (Exp 3-4). Using the SIMPLE model, we factored in the retention delays between encoding and retrieval (delays of 24 h, 15 min, 1.5-2.5 s, and 0.5 s for Exp 1-4, respectively) and computed a temporal similarity score for each trial. We found a positive relation between similarity and retrieval times; that is, the more temporally similar two events, the slower the retrieval of their temporal order. Using Bayesian analysis, we confirmed the equivalence of the RT/similarity relation across all experiments, which included a vast range of temporal distances and retention delays. These results provide evidence for scale invariance during the retrieval of temporal order of episodic memories. PMID:25909581

  19. Event attribution using data assimilation in an intermediate complexity atmospheric model

    NASA Astrophysics Data System (ADS)

    Metref, Sammy; Hannart, Alexis; Ruiz, Juan; Carrassi, Alberto; Bocquet, Marc; Ghil, Michael

    2016-04-01

    A new approach, coined DADA (Data Assimilation for Detection and Attribution) has been recently introduced by Hannart et al. 2015, and is potentially useful for near real time, systematic causal attribution of weather and climate-related events The method is purposely designed to allow its operability at meteorological centers by synergizing causal attribution with Data Assimilation (DA) methods usually designed to deal with large nonlinear models. In Hannart et al. 2015, the DADA proposal is illustrated in the context of a low-order nonlinear model (forced three-variable Lorenz model) that is of course not realistic to represent the events considered. As a continuation of this stream of work, we therefore propose an implementation of the DADA approach in a realistic intermediate complexity atmospheric model (ICTP AGCM, nicknamed SPEEDY). The SPEEDY model is based on a spectral dynamical core developed at the Geophysical Fluid Dynamics Laboratory (see Held and Suarez 1994). It is a hydrostatic, r-coordinate, spectral-transform model in the vorticity-divergence form described by Bourke (1974). A synthetic dataset of observations of an extreme precipitation event over Southeastern South America is extracted from a long SPEEDY simulation under present climatic conditions (i.e. factual conditions). Then, following the DADA approach, observations of this event are assimilated twice in the SPEEDY model: first in the factual configuration of the model and second under its counterfactual, pre-industrial configuration. We show that attribution can be performed based on the likelihood ratio as in Hannart et al. 2015, but we further extend this result by showing that the likelihood can be split in space, time and variables in order to help identify the specific physical features of the event that bear the causal signature. References: Hannart A., A. Carrassi, M. Bocquet, M. Ghil, P. Naveau, M. Pulido, J. Ruiz, P. Tandeo (2015) DADA: Data assimilation for the detection and

  20. Affective and Cardiovascular Responding to Unpleasant Events from Adolescence to Old Age: Complexity of Events Matters

    ERIC Educational Resources Information Center

    Wrzus, Cornelia; Muller, Viktor; Wagner, Gert G.; Lindenberger, Ulman; Riediger, Michaela

    2013-01-01

    Two studies investigated the "overpowering hypothesis" as a possible explanation for the currently inconclusive empirical picture on age differences in affective responding to unpleasant events. The overpowering hypothesis predicts that age differences in affective responding are particularly evident in highly resource-demanding situations that…

  1. Management of a Complex Open Channel Network During Flood Events

    NASA Astrophysics Data System (ADS)

    Franchini, M.; Valiani, A.; Schippa, L.; Mascellani, G.

    2003-04-01

    Most part of the area around Ferrara (Italy) is below the mean sea level and an extensive drainage system combined with several pump stations allows the use of this area for both urban development and industrial and agricultural activities. The three main channels of this hydraulic system constitute the Ferrara Inland Waterway (total length approximately 70 km), which connects the Po river near Ferrara to the sea. Because of the level difference between the upstream and dowstream ends of the waterway, three locks are located along it, each of them combined with a set of gates to control the water levels. During rainfall events, most of the water of the basin flows into the waterway and heavy precipitations sometimes cause flooding in several areas. This is due to the insufficiency of the channel network dimensions and an inadequate manual operation of the gates. This study presents a hydrological-hydraulic model for the entire Ferrara basin and a system of rules in order to operate the gates. In particular, their opening is designed to be regulated in real time by monitoring the water level in several sections along the channels. Besides flood peak attenuation, this operation strategy contributes also to the maintenance of a constant water level for irrigation and fluvial navigation during the dry periods. With reference to the flood event of May 1996, it is shown that this floodgate operation policy, unlike that which was actually adopted during that event, would lead to a significant flood peak attenuation, avoiding flooding in the area upstream of Ferrara.

  2. HIGH-PRECISION BIOLOGICAL EVENT EXTRACTION: EFFECTS OF SYSTEM AND OF DATA

    PubMed Central

    Cohen, K. Bretonnel; Verspoor, Karin; Johnson, Helen L.; Roeder, Chris; Ogren, Philip V.; Baumgartner, William A.; White, Elizabeth; Tipney, Hannah; Hunter, Lawrence

    2013-01-01

    We approached the problems of event detection, argument identification, and negation and speculation detection in the BioNLP’09 information extraction challenge through concept recognition and analysis. Our methodology involved using the OpenDMAP semantic parser with manually written rules. The original OpenDMAP system was updated for this challenge with a broad ontology defined for the events of interest, new linguistic patterns for those events, and specialized coordination handling. We achieved state-of-the-art precision for two of the three tasks, scoring the highest of 24 teams at precision of 71.81 on Task 1 and the highest of 6 teams at precision of 70.97 on Task 2. We provide a detailed analysis of the training data and show that a number of trigger words were ambiguous as to event type, even when their arguments are constrained by semantic class. The data is also shown to have a number of missing annotations. Analysis of a sampling of the comparatively small number of false positives returned by our system shows that major causes of this type of error were failing to recognize second themes in two-theme events, failing to recognize events when they were the arguments to other events, failure to recognize nontheme arguments, and sentence segmentation errors. We show that specifically handling coordination had a small but important impact on the overall performance of the system. The OpenDMAP system and the rule set are available at http://bionlp.sourceforge.net. PMID:25937701

  3. Robot traders can prevent extreme events in complex stock markets

    NASA Astrophysics Data System (ADS)

    Suhadolnik, Nicolas; Galimberti, Jaqueson; Da Silva, Sergio

    2010-11-01

    If stock markets are complex, monetary policy and even financial regulation may be useless to prevent bubbles and crashes. Here, we suggest the use of robot traders as an anti-bubble decoy. To make our case, we put forward a new stochastic cellular automata model that generates an emergent stock price dynamics as a result of the interaction between traders. After introducing socially integrated robot traders, the stock price dynamics can be controlled, so as to make the market more Gaussian.

  4. Automatic Building Extraction From LIDAR Data Covering Complex Urban Scenes

    NASA Astrophysics Data System (ADS)

    Awrangjeb, M.; Lu, G.; Fraser, C.

    2014-08-01

    proposed method offers higher building detection and roof plane extraction rates than many existing methods, especially in complex urban scenes.

  5. Knowledge-based extraction of adverse drug events from biomedical text

    PubMed Central

    2014-01-01

    Background Many biomedical relation extraction systems are machine-learning based and have to be trained on large annotated corpora that are expensive and cumbersome to construct. We developed a knowledge-based relation extraction system that requires minimal training data, and applied the system for the extraction of adverse drug events from biomedical text. The system consists of a concept recognition module that identifies drugs and adverse effects in sentences, and a knowledge-base module that establishes whether a relation exists between the recognized concepts. The knowledge base was filled with information from the Unified Medical Language System. The performance of the system was evaluated on the ADE corpus, consisting of 1644 abstracts with manually annotated adverse drug events. Fifty abstracts were used for training, the remaining abstracts were used for testing. Results The knowledge-based system obtained an F-score of 50.5%, which was 34.4 percentage points better than the co-occurrence baseline. Increasing the training set to 400 abstracts improved the F-score to 54.3%. When the system was compared with a machine-learning system, jSRE, on a subset of the sentences in the ADE corpus, our knowledge-based system achieved an F-score that is 7 percentage points higher than the F-score of jSRE trained on 50 abstracts, and still 2 percentage points higher than jSRE trained on 90% of the corpus. Conclusion A knowledge-based approach can be successfully used to extract adverse drug events from biomedical text without need for a large training set. Whether use of a knowledge base is equally advantageous for other biomedical relation-extraction tasks remains to be investigated. PMID:24593054

  6. Enhancing Complex System Performance Using Discrete-Event Simulation

    SciTech Connect

    Allgood, Glenn O; Olama, Mohammed M; Lake, Joe E

    2010-01-01

    In this paper, we utilize discrete-event simulation (DES) merged with human factors analysis to provide the venue within which the separation and deconfliction of the system/human operating principles can occur. A concrete example is presented to illustrate the performance enhancement gains for an aviation cargo flow and security inspection system achieved through the development and use of a process DES. The overall performance of the system is computed, analyzed, and optimized for the different system dynamics. Various performance measures are considered such as system capacity, residual capacity, and total number of pallets waiting for inspection in the queue. These metrics are performance indicators of the system's ability to service current needs and respond to additional requests. We studied and analyzed different scenarios by changing various model parameters such as the number of pieces per pallet ratio, number of inspectors and cargo handling personnel, number of forklifts, number and types of detection systems, inspection modality distribution, alarm rate, and cargo closeout time. The increased physical understanding resulting from execution of the queuing model utilizing these vetted performance measures identified effective ways to meet inspection requirements while maintaining or reducing overall operational cost and eliminating any shipping delays associated with any proposed changes in inspection requirements. With this understanding effective operational strategies can be developed to optimally use personnel while still maintaining plant efficiency, reducing process interruptions, and holding or reducing costs.

  7. Stereochemically constrained complex organic molecules extracted from olivine crystal matrix

    NASA Astrophysics Data System (ADS)

    Gerasimenko, I.; Freund, F. T.; Imanaka, H.; Rodgers, R.

    2011-12-01

    Paradoxically, the dense solid state of magmatic minerals is a medium, in which organic synthesis can take place. The reason is that gas-fluid components such as H2O, CO/CO2/N2 and H2S are omnipresent in terrestrial magmatic environments. Any silicate mineral that crystallizes from such magmas will incorporate small quantities of the fluid-phase components in the form of structurally incompatible low-z impurities. During cooling the solute species undergo a redox conversion, resulting in chemically reduced low-z elements. To the extent that these low-z impurities are diffusively mobile, they will exsolve to the surface and/or to major structural defects inside the crystal matrix such as dislocations. Dislocations provide a 3-D structured environment, where the low-z impurities will tend to form stereochemically constrained polyatomic Cn-H-O-N-S entities, which we call organic protomolecules. In Nature, during weathering, such protomolecules will be released into the environment in the form of complex organic molecules. In our study we crush samples under clean conditions as a way to expose Cn-H-O-N-S entities at the fracture surfaces. We conduct identical experiments with selected large olivine single crystals, mm-sized olivine from peridiotite nodules from the San Carlos Volcanic Field, Arizona, and the vesiculated basalt that had carried the nodules upward in the volcanic conduit. We Soxhlet-extract the crushed powders with water, THF and ethyl acetate. The extracts are analyzed at the FTICR-MS facility at Florida State University using ultrahigh resolution Mass Spectrometry techniques capable of determining the chemical composition of the organic molecules up to 600 amu and more. So far we have found several analog sequences of oxygen-rich aliphatic hydrocarbons, families with up to 34 carbon atoms, probably poly-carboxylic acids, and some families containing sulfur.

  8. Complex dynamic scene perception: effects of attentional set on perceiving single and multiple event types.

    PubMed

    Sanocki, Thomas; Sulman, Noah

    2013-04-01

    Three experiments measured the efficiency of monitoring complex scenes composed of changing objects, or events. All events lasted about 4 s, but in a given block of trials, could be of a single type (single task) or of multiple types (multitask, with a total of four event types). Overall accuracy of detecting target events amid distractors was higher for single event types relative to multiple types. Multiple event types were processed reasonably well when each event type was restricted to its own region, and much worse when event types were mixed in location. In most task conditions, observers reached an optimal level of performance (optimal attentional set). After one target was identified, performance for other targets dropped markedly and then recovered to optimal levels. However, set was not optimized when task locations were intermixed. The results support the idea that attentional set determines the efficiency of event perception in complex scenes. Although single event set was most efficient, there can be a reasonably efficient set for multiple event types. PMID:23181683

  9. Semantic Complex Event Processing over End-to-End Data Flows

    SciTech Connect

    Zhou, Qunzhi; Simmhan, Yogesh; Prasanna, Viktor K.

    2012-04-01

    Emerging Complex Event Processing (CEP) applications in cyber physical systems like SmartPower Grids present novel challenges for end-to-end analysis over events, flowing from heterogeneous information sources to persistent knowledge repositories. CEP for these applications must support two distinctive features - easy specification patterns over diverse information streams, and integrated pattern detection over realtime and historical events. Existing work on CEP has been limited to relational query patterns, and engines that match events arriving after the query has been registered. We propose SCEPter, a semantic complex event processing framework which uniformly processes queries over continuous and archived events. SCEPteris built around an existing CEP engine with innovative support for semantic event pattern specification and allows their seamless detection over past, present and future events. Specifically, we describe a unified semantic query model that can operate over data flowing through event streams to event repositories. Compile-time and runtime semantic patterns are distinguished and addressed separately for efficiency. Query rewriting is examined and analyzed in the context of temporal boundaries that exist between event streams and their repository to avoid duplicate or missing results. The design and prototype implementation of SCEPterare analyzed using latency and throughput metrics for scenarios from the Smart Grid domain.

  10. Extraction of events and rules of land use/cover change from the policy text

    NASA Astrophysics Data System (ADS)

    Lin, Guangfa; Xia, Beicheng; Huang, Wangli; Jiang, Huixian; Chen, Youfei

    2007-06-01

    The database of recording the snapshots of land parcels history is the foundation for the most of the models on simulating land use/cover change (LUCC) process. But the sequences of temporal snapshots are not sufficient to deduce and describe the mechanism of LUCC process. The temporal relationship between scenarios of LUCC we recorded could not be transfer into causal relationship categorically, which was regarded as a key factor in spatial-temporal reasoning. The proprietor of land parcels adapted themselves to the policies from governments and the change of production market, and then made decisions in this or that way. The occurrence of each change of a land parcel in an urban area was often related with one or more decision texts when it was investigated on the local scale with high resolution of the background scene. These decision texts may come from different sections of a hierarchical government system on different levels, such as villages or communities, towns or counties, cities, provinces or even the paramount. All these texts were balance results between advantages and disadvantages of different interest groups. They are the essential forces of LUCC in human dimension. Up to now, a methodology is still wanted for on how to express these forces in a simulation system using GIS as a language. The presented paper was part of our initial research on this topic. The term "Event" is a very important concept in the frame of "Object-Oriented" theory in computer science. While in the domain of temporal GIS, the concept of event was developed in another category. The definitions of the event and their transformation relationship were discussed in this paper on three modeling levels as real world level, conceptual level and programming level. In this context, with a case study of LUCC in recent 30 years in Xiamen city of Fujian province, P. R. China, the paper focused on how to extract information of events and rules from the policy files collected and integrate

  11. Extraction Of Adverse Events From Clinical Documents To Support Decision Making Using Semantic Preprocessing.

    PubMed

    Gaebel, Jan; Kolter, Till; Arlt, Felix; Denecke, Kerstin

    2015-01-01

    Clinical documentation is usually stored in unstructured format in electronic health records (EHR). Processing the information is inconvenient and time consuming and should be enhanced by computer systems. In this paper, a rule-based method is introduced that identifies adverse events documented in the EHR that occurred during treatment. For this purpose, clinical documents are transformed into a semantic structure from which adverse events are extracted. The method is evaluated in a user study with neurosurgeons. In comparison to a bag of word classification using support vector machines, our approach achieved comparably good results of 65% recall and 78% precision. In conclusion, the rule-based method generates promising results that can support physicians' decision making. Because of the structured format the data can be reused for other purposes as well. PMID:26262330

  12. BioContext: an integrated text mining system for large-scale extraction and contextualization of biomolecular events

    PubMed Central

    Gerner, Martin; Sarafraz, Farzaneh; Bergman, Casey M.; Nenadic, Goran

    2012-01-01

    Motivation: Although the amount of data in biology is rapidly increasing, critical information for understanding biological events like phosphorylation or gene expression remains locked in the biomedical literature. Most current text mining (TM) approaches to extract information about biological events are focused on either limited-scale studies and/or abstracts, with data extracted lacking context and rarely available to support further research. Results: Here we present BioContext, an integrated TM system which extracts, extends and integrates results from a number of tools performing entity recognition, biomolecular event extraction and contextualization. Application of our system to 10.9 million MEDLINE abstracts and 234 000 open-access full-text articles from PubMed Central yielded over 36 million mentions representing 11.4 million distinct events. Event participants included over 290 000 distinct genes/proteins that are mentioned more than 80 million times and linked where possible to Entrez Gene identifiers. Over a third of events contain contextual information such as the anatomical location of the event occurrence or whether the event is reported as negated or speculative. Availability: The BioContext pipeline is available for download (under the BSD license) at http://www.biocontext.org, along with the extracted data which is also available for online browsing. Contact: martin.gerner@gmail.com Supplementary information: Supplementary data are available at Bioinformatics online. PMID:22711795

  13. An extended grammar system for learning and recognizing complex visual events.

    PubMed

    Zhang, Zhang; Tan, Tieniu; Huang, Kaiqi

    2011-02-01

    For a grammar-based approach to the recognition of visual events, there are two major limitations that prevent it from real application. One is that the event rules are predefined by domain experts, which means huge manual cost. The other is that the commonly used grammar can only handle sequential relations between subevents, which is inadequate to recognize more complex events involving parallel subevents. To solve these problems, we propose an extended grammar approach to modeling and recognizing complex visual events. First, motion trajectories as original features are transformed into a set of basic motion patterns of a single moving object, namely, primitives (terminals) in the grammar system. Then, a Minimum Description Length (MDL) based rule induction algorithm is performed to discover the hidden temporal structures in primitive stream, where Stochastic Context-Free Grammar (SCFG) is extended by Allen's temporal logic to model the complex temporal relations between subevents. Finally, a Multithread Parsing (MTP) algorithm is adopted to recognize interesting complex events in a given primitive stream, where a Viterbi-like error recovery strategy is also proposed to handle large-scale errors, e.g., insertion and deletion errors. Extensive experiments, including gymnastic exercises, traffic light events, and multi-agent interactions, have been executed to validate the effectiveness of the proposed approach. PMID:21193807

  14. Complex active regions as the main source of extreme and large solar proton events

    NASA Astrophysics Data System (ADS)

    Ishkov, V. N.

    2013-12-01

    A study of solar proton sources indicated that solar flare events responsible for ≥2000 pfu proton fluxes mostly occur in complex active regions (CARs), i.e., in transition structures between active regions and activity complexes. Different classes of similar structures and their relation to solar proton events (SPEs) and evolution, depending on the origination conditions, are considered. Arguments in favor of the fact that sunspot groups with extreme dimensions are CARs are presented. An analysis of the flare activity in a CAR resulted in the detection of "physical" boundaries, which separate magnetic structures of the same polarity and are responsible for the independent development of each structure.

  15. Effects of Grammaticality and Morphological Complexity on the P600 Event-Related Potential Component

    PubMed Central

    Wampler, Emma K.; Valentine, Geoffrey D.; Osterhout, Lee

    2015-01-01

    We investigated interactions between morphological complexity and grammaticality on electrophysiological markers of grammatical processing during reading. Our goal was to determine whether morphological complexity and stimulus grammaticality have independent or additive effects on the P600 event-related potential component. Participants read sentences that were either well-formed or grammatically ill-formed, in which the critical word was either morphologically simple or complex. Results revealed no effects of complexity for well-formed stimuli, but the P600 amplitude was significantly larger for morphologically complex ungrammatical stimuli than for morphologically simple ungrammatical stimuli. These findings suggest that some previous work may have inadequately characterized factors related to reanalysis during morphosyntactic processing. Our results show that morphological complexity by itself does not elicit P600 effects. However, in ungrammatical circumstances, overt morphology provides a more robust and reliable cue to morphosyntactic relationships than null affixation. PMID:26488893

  16. Single Event Testing on Complex Devices: Test Like You Fly Versus Test-Specific Design Structures

    NASA Technical Reports Server (NTRS)

    Berg, Melanie D.; Label, Kenneth

    2016-01-01

    We present a mechanism for evaluating complex digital systems targeted for harsh radiation environments such as space. Focus is limited to analyzing the single event upset (SEU) susceptibility of designs implemented inside Field Programmable Gate Array (FPGA) devices. Tradeoffs are provided between application-specific versus test-specific test structures.

  17. Everyday Matters in Science and Mathematics: Studies of Complex Classroom Events

    ERIC Educational Resources Information Center

    Nemirovsky, Ricardo, Ed.; Rosebery, Ann S., Ed.; Solomon, Jesse, Ed.; Warren, Beth, Ed.

    2005-01-01

    This book re-examines the dichotomy between the everyday and the disciplinary in mathematics and science education, and explores alternatives to this opposition from points of view grounded in the close examination of complex classroom events. It makes the case that students' everyday experience and knowledge in their entire manifold forms matter…

  18. A Method for Group Extraction in Complex Social Networks

    NASA Astrophysics Data System (ADS)

    Bródka, Piotr; Musial, Katarzyna; Kazienko, Przemysław

    The extraction of social groups from social networks existing among employees in the company, its customers or users of various computer systems became one of the research areas of growing importance. Once we have discovered the groups, we can utilise them, in different kinds of recommender systems or in the analysis of the team structure and communication within a given population.

  19. Event-triggered synchronization strategy for complex dynamical networks with the Markovian switching topologies.

    PubMed

    Wang, Aijuan; Dong, Tao; Liao, Xiaofeng

    2016-02-01

    This paper concerns the synchronization problem of complex networks with the random switching topologies. By modeling the switching of network topologies as a Markov process, a novel event-triggered synchronization strategy is proposed. Unlike the existing strategies, the event detection of this strategy only works at the network topology switching time instant, which can significantly decrease the communication frequency between nodes and save the network resources. Under this strategy, the synchronization problem of complex network is equivalently converted to the stability of a class of Markovian jump systems with a time-varying delay. By using the Lyapunov-Krasovskii functional method and the weak infinitesimal operation, a sufficient condition for the mean square synchronization of the complex networks subject to Markovian switching topologies is established. Finally, a numerical simulation example is provided to demonstrate the theoretical results. PMID:26650712

  20. Cell-based screening: extracting meaning from complex data.

    PubMed

    Finkbeiner, Steven; Frumkin, Michael; Kassner, Paul D

    2015-04-01

    Unbiased discovery approaches have the potential to uncover neurobiological insights into CNS disease and lead to the development of therapies. Here, we review lessons learned from imaging-based screening approaches and recent advances in these areas, including powerful new computational tools to synthesize complex data into more useful knowledge that can reliably guide future research and development. PMID:25856492

  1. Cell-Based Screening: Extracting Meaning from Complex Data

    PubMed Central

    Finkbeiner, Steven; Frumkin, Michael; Kassner, Paul D.

    2015-01-01

    Summary Unbiased discovery approaches have the potential to uncover neurobiological insights into CNS disease and lead to the development of therapies. Here we review lessons learned from imaging-based screening approaches and recent advances in these areas, including powerful new computational tools to synthesize complex data into more useful knowledge that can reliably guide future research and development. PMID:25856492

  2. A solvent extraction study of molybdenum chloride and molybdenum thiocyanate complexes

    USGS Publications Warehouse

    Greenland, L.P.; Lillie, E.G.

    1974-01-01

    The effect of reducing agents on molybdenum(VI) solutions in hydrochloric acid was studied by a solvent extraction technique to elucidate the composition of the colored molybdenum thiocyanate complex. Neither copper(I) chloride nor ascorbic acid have any effect on the extraction of MoO2Cl2; it is inferred that tin(II) chloride reduces Mo(VI) stepwise to a polynuclear Mo(V)??Mo(VI) complex and then to Mo(V). The colored thiocyanate complex produced by copper(I) and by ascorbic acid differs only slightly in extraction characteristics from the uncolored Mo(VI) complex. It is suggested that the color may be produced by an isomerization reaction of MoO2(SCN)2, and thus that the colored species may be a hexavalent rather than pentavalent molybdenum complex. ?? 1974.

  3. Capacitance extraction from complex 3D interconnect structures

    SciTech Connect

    Cartwright, D.; Csanak, G.; George, D.; Walker, R.; Kuprat, A.; Dengi, A.; Grobman, W.

    1999-06-01

    A new tool has been developed for calculating the capacitance matrix for complex 3D interconnect structures involving multiple layers of irregularly shaped interconnect, imbedded in different dielectric materials. This method utilizes a new 3D adaptive unstructured grid capability, and a linear finite element algorithm. The capacitance is determined from the minimum in the total system energy as the nodes are varied to minimize the error in the electric field in the dielectric(s).

  4. Maximum likelihood: Extracting unbiased information from complex networks

    NASA Astrophysics Data System (ADS)

    Garlaschelli, Diego; Loffredo, Maria I.

    2008-07-01

    The choice of free parameters in network models is subjective, since it depends on what topological properties are being monitored. However, we show that the maximum likelihood (ML) principle indicates a unique, statistically rigorous parameter choice, associated with a well-defined topological feature. We then find that, if the ML condition is incompatible with the built-in parameter choice, network models turn out to be intrinsically ill defined or biased. To overcome this problem, we construct a class of safely unbiased models. We also propose an extension of these results that leads to the fascinating possibility to extract, only from topological data, the “hidden variables” underlying network organization, making them “no longer hidden.” We test our method on World Trade Web data, where we recover the empirical gross domestic product using only topological information.

  5. On the Complexity of Constraint-Based Theory Extraction

    NASA Astrophysics Data System (ADS)

    Boley, Mario; Gärtner, Thomas

    In this paper we rule out output polynomial listing algorithms for the general problem of discovering theories for a conjunction of monotone and anti-monotone constraints as well as for the particular subproblem in which all constraints are frequency-based. For the general problem we prove a concrete exponential lower time bound that holds for any correct algorithm and even in cases in which the size of the theory as well as the only previous bound are constant. For the case of frequency-based constraints our result holds unless P = NP. These findings motivate further research to identify tractable subproblems and justify approaches with exponential worst case complexity.

  6. Self-Structures, Negative Events, and Adolescent Depression: Clarifying the Role of Self-Complexity in a Prospective, Multiwave Study

    ERIC Educational Resources Information Center

    Cohen, Joseph R.; Spiegler, Kevin M.; Young, Jami F.; Hankin, Benjamin L.; Abela, John R. Z.

    2014-01-01

    The purpose of this multiwave longitudinal study was to examine the structure of self-complexity and its relation to depressive symptoms in 276 adolescents (M = 12.55; SD = 1.04). Self-complexity, depressive symptoms, and negative events were assessed during a laboratory assessment at baseline, and then depressive symptoms and negative events were…

  7. Measurement and Information Extraction in Complex Dynamics Quantum Computation

    NASA Astrophysics Data System (ADS)

    Casati, Giulio; Montangero, Simone

    Quantum Information processing has several di.erent applications: some of them can be performed controlling only few qubits simultaneously (e.g. quantum teleportation or quantum cryptography) [1]. Usually, the transmission of large amount of information is performed repeating several times the scheme implemented for few qubits. However, to exploit the advantages of quantum computation, the simultaneous control of many qubits is unavoidable [2]. This situation increases the experimental di.culties of quantum computing: maintaining quantum coherence in a large quantum system is a di.cult task. Indeed a quantum computer is a many-body complex system and decoherence, due to the interaction with the external world, will eventually corrupt any quantum computation. Moreover, internal static imperfections can lead to quantum chaos in the quantum register thus destroying computer operability [3]. Indeed, as it has been shown in [4], a critical imperfection strength exists above which the quantum register thermalizes and quantum computation becomes impossible. We showed such e.ects on a quantum computer performing an e.cient algorithm to simulate complex quantum dynamics [5,6].

  8. Psychological distress and stressful life events in pediatric complex regional pain syndrome

    PubMed Central

    Wager, Julia; Brehmer, Hannah; Hirschfeld, Gerrit; Zernikow, Boris

    2015-01-01

    BACKGROUND: There is little knowledge regarding the association between psychological factors and complex regional pain syndrome (CRPS) in children. Specifically, it is not known which factors precipitate CRPS and which result from the ongoing painful disease. OBJECTIVES: To examine symptoms of depression and anxiety as well as the experience of stressful life events in children with CRPS compared with children with chronic primary headaches and functional abdominal pain. METHODS: A retrospective chart study examined children with CRPS (n=37) who received intensive inpatient pain treatment between 2004 and 2010. They were compared with two control groups (chronic primary headaches and functional abdominal pain; each n=37), who also received intensive inpatient pain treatment. Control groups were matched with the CRPS group with regard to admission date, age and sex. Groups were compared on symptoms of depression and anxiety as well as stressful life events. RESULTS: Children with CRPS reported lower anxiety and depression scores compared with children with abdominal pain. A higher number of stressful life events before and after the onset of the pain condition was observed for children with CRPS. CONCLUSIONS: Children with CRPS are not particularly prone to symptoms of anxiety or depression. Importantly, children with CRPS experienced more stressful life events than children with chronic headaches or abdominal pain. Prospective long-term studies are needed to further explore the potential role of stressful life events in the etiology of CRPS. PMID:26035287

  9. Anion effects in the extraction of lanthanide 2-thenoyltrifluoroacetone complexes into an ionic liquid

    SciTech Connect

    Jensen, Mark P.; Beitz, James V.; Rickert, Paul G.; Borkowski, Marian; Laszak, Ivan; Dietz, Mark L.

    2012-07-01

    The extraction of trivalent lanthanides from an aqueous phase containing 1 M NaClO{sub 4} into the room temperature ionic liquid 1-butyl-3-methylimidazolium nonafluoro-1-butane sulfonate by the beta-diketone extractant 2-thenoyltrifluoroacetone (Htta) was studied. Radiotracer distribution, absorption spectroscopy, time-resolved laser-induced fluorescence spectroscopy, and X-ray absorption fine structure measurements point to the extraction of multiple lanthanide species. At low extractant concentrations, fully hydrated aqua cations of the lanthanides are present in the ionic liquid phase. As the extractant concentration is increased 1:2 and 1:3 lanthanide:tta species are observed. In contrast, 1:4 Ln:tta complexes were observed in the extraction of lanthanides by Htta into 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide. (authors)

  10. Extraction of complex refractive index dispersion from SPR data

    NASA Astrophysics Data System (ADS)

    Nakkach, Mohamed; Moreau, Julien; Canva, Michael

    2010-02-01

    Surface Plasmon Resonnance (SPR) techniques have been mostly set-up as angular reflectivity interrogation mode using quasi-monochromatic light or as spectral reflectivity interrogation mode at one given wavelength, providing information about variation of effective optical thickness ▵n.e above the metal surface. In this communication we present a dual mode sensor working both in angular and spectral interrogation modes. A white light illuminates the sensor surface and the reflectivity spectra in TE and TM polarization are measured with a spectrometer. By changing the angular coupling conditions, a complete reflectivity surface R(θ, λ) can be measured. The 2D reflectivity decrease valley is affected by both the real and imaginary part of the optical index of the dielectric medium as well as their spectral dispersion. With such experimental data set, it is possible to back calculate the dispersion of the complex refractive index of the dielectric layer. This is demonstrated using a turquoise dye doped solution. According to the Kramers-Kronig relations, the imaginary part of the refractive index for an absorbing medium is proportional to the absorption while the real part presents a large dispersion around the absorption wavelength. The reflectivity surface R(θ, λ) was measured from 500 nm to 750 nm over about 8° angular range. The whole complex refractive optical index of the doped solution, absorbing around 630 nm, was reconstructed from the SPR reflectivity experimental data, using a homemade program based on an extended Rouard method to fit the experimental angular plasmon data for each wavelength. These results show that the classical SPR technique can be extended to acquire precise spectral information about biomolecular interactions occurring on the metallic layer.

  11. Complex Settlement Pattern Extraction With Multi-instance Learning

    SciTech Connect

    Vatsavai, Raju; Bhaduri, Budhendra L; Graesser, Jordan B

    2013-01-01

    Per-pixel (or single instance) based classification schemes which have proven to be very useful in thematic classification have shown to be inadequate when it comes to analyzing very high resolution remote sensing imagery. The main problem being that the pixel size (less than a meter) is too small as compared to the typical object size (100s of meters) and contains too little contextual information to accurately distinguish complex settlement types. One way to alleviate this problem is to consider a bigger window or patch/segment consisting a group of adjacent pixels which offers better spatial context than a single pixel. Unfortunately, this makes per-pixel based classification schemes ineffective. In this work, we look at a new class of machine learning approaches, called multi-instance learning, where instead of assigning class labels to individual instances (pixels), a label is assigned to the bag (all pixels in a window or segment). We applied this multi-instance learning approach for identifying two important urban patterns, namely formal and informal settlements. Experimental evaluation shows the better performance of multi-instance learning over several well-known single-instance classification schemes.

  12. Complex Events Initiated by Individual Spikes in the Human Cerebral Cortex

    PubMed Central

    Komlósi, Gergely; Füle, Miklós; Szabadics, János; Varga, Csaba; Barzó, Pál; Tamás, Gábor

    2008-01-01

    Synaptic interactions between neurons of the human cerebral cortex were not directly studied to date. We recorded the first dataset, to our knowledge, on the synaptic effect of identified human pyramidal cells on various types of postsynaptic neurons and reveal complex events triggered by individual action potentials in the human neocortical network. Brain slices were prepared from nonpathological samples of cortex that had to be removed for the surgical treatment of brain areas beneath association cortices of 58 patients aged 18 to 73 y. Simultaneous triple and quadruple whole-cell patch clamp recordings were performed testing mono- and polysynaptic potentials in target neurons following a single action potential fired by layer 2/3 pyramidal cells, and the temporal structure of events and underlying mechanisms were analyzed. In addition to monosynaptic postsynaptic potentials, individual action potentials in presynaptic pyramidal cells initiated long-lasting (37 ± 17 ms) sequences of events in the network lasting an order of magnitude longer than detected previously in other species. These event series were composed of specifically alternating glutamatergic and GABAergic postsynaptic potentials and required selective spike-to-spike coupling from pyramidal cells to GABAergic interneurons producing concomitant inhibitory as well as excitatory feed-forward action of GABA. Single action potentials of human neurons are sufficient to recruit Hebbian-like neuronal assemblies that are proposed to participate in cognitive processes. PMID:18767905

  13. Inhibition of selective signaling events in natural killer cells recognizing major histocompatibility complex class I.

    PubMed Central

    Kaufman, D S; Schoon, R A; Robertson, M J; Leibson, P J

    1995-01-01

    Many studies have characterized the transmembrane signaling events initiated after T-cell antigen receptor recognition of major histocompatibility complex (MHC)-bound peptides. Yet, little is known about signal transduction from a set of MHC class I recognizing receptors on natural killer (NK) cells whose ligation dramatically inhibits NK cell-mediated killing. In this study we evaluated the influence of MHC recognition on the proximal signaling events in NK cells binding tumor targets. We utilized two experimental models where NK cell-mediated cytotoxicity was fully inhibited by the recognition of specific MHC class I molecules. NK cell binding to either class I-deficient or class I-transfected target cells initiated rapid protein tyrosine kinase activation. In contrast, whereas NK cell binding to class I-deficient targets led to inositol phosphate release and increased intracellular free calcium ([Ca2+]i), NK recognition of class I-bearing targets did not induce the activation of these phospholipase C-dependent signaling events. The recognition of class I by NK cells clearly had a negative regulatory effect since blocking this interaction using anti-class I F(ab')2 fragments increased inositol 1,4,5-trisphosphate release and [Ca2+]i and increased the lysis of the targets. These results suggest that one of the mechanisms by which NK cell recognition of specific MHC class I molecules can block the development of cell-mediated cytotoxicity is by inhibiting specific critical signaling events. Images Fig. 2 Fig. 4 PMID:7604018

  14. Feature Extraction of Event-Related Potentials Using Wavelets: An Application to Human Performance Monitoring

    NASA Technical Reports Server (NTRS)

    Trejo, Leonard J.; Shensa, Mark J.; Remington, Roger W. (Technical Monitor)

    1998-01-01

    This report describes the development and evaluation of mathematical models for predicting human performance from discrete wavelet transforms (DWT) of event-related potentials (ERP) elicited by task-relevant stimuli. The DWT was compared to principal components analysis (PCA) for representation of ERPs in linear regression and neural network models developed to predict a composite measure of human signal detection performance. Linear regression models based on coefficients of the decimated DWT predicted signal detection performance with half as many f ree parameters as comparable models based on PCA scores. In addition, the DWT-based models were more resistant to model degradation due to over-fitting than PCA-based models. Feed-forward neural networks were trained using the backpropagation,-, algorithm to predict signal detection performance based on raw ERPs, PCA scores, or high-power coefficients of the DWT. Neural networks based on high-power DWT coefficients trained with fewer iterations, generalized to new data better, and were more resistant to overfitting than networks based on raw ERPs. Networks based on PCA scores did not generalize to new data as well as either the DWT network or the raw ERP network. The results show that wavelet expansions represent the ERP efficiently and extract behaviorally important features for use in linear regression or neural network models of human performance. The efficiency of the DWT is discussed in terms of its decorrelation and energy compaction properties. In addition, the DWT models provided evidence that a pattern of low-frequency activity (1 to 3.5 Hz) occurring at specific times and scalp locations is a reliable correlate of human signal detection performance.

  15. Feature extraction of event-related potentials using wavelets: an application to human performance monitoring

    NASA Technical Reports Server (NTRS)

    Trejo, L. J.; Shensa, M. J.

    1999-01-01

    This report describes the development and evaluation of mathematical models for predicting human performance from discrete wavelet transforms (DWT) of event-related potentials (ERP) elicited by task-relevant stimuli. The DWT was compared to principal components analysis (PCA) for representation of ERPs in linear regression and neural network models developed to predict a composite measure of human signal detection performance. Linear regression models based on coefficients of the decimated DWT predicted signal detection performance with half as many free parameters as comparable models based on PCA scores. In addition, the DWT-based models were more resistant to model degradation due to over-fitting than PCA-based models. Feed-forward neural networks were trained using the backpropagation algorithm to predict signal detection performance based on raw ERPs, PCA scores, or high-power coefficients of the DWT. Neural networks based on high-power DWT coefficients trained with fewer iterations, generalized to new data better, and were more resistant to overfitting than networks based on raw ERPs. Networks based on PCA scores did not generalize to new data as well as either the DWT network or the raw ERP network. The results show that wavelet expansions represent the ERP efficiently and extract behaviorally important features for use in linear regression or neural network models of human performance. The efficiency of the DWT is discussed in terms of its decorrelation and energy compaction properties. In addition, the DWT models provided evidence that a pattern of low-frequency activity (1 to 3.5 Hz) occurring at specific times and scalp locations is a reliable correlate of human signal detection performance. Copyright 1999 Academic Press.

  16. Extraction of lycopene from tomato paste by ursodeoxycholic acid using the selective inclusion complex method.

    PubMed

    Seifi, Mahmoud; Seifi, Parisa; Hadizadeh, Farzin; Mohajeri, Seyed Ahmad

    2013-11-01

    Lycopene, a precursor of β-carotene with well-known antioxidant activity and powerful health properties, can be found in many natural products such as tomato (Lycopersicon esculentum), watermelon, red pepper, and papaya. Many separation methods have been reported for extracting lycopene from its sources. The inclusion complex is an effective method for extraction and purification of organic chemicals. This procedure has 2 main components: host and guest molecules. In this study, lycopene (guest) was extracted from tomato paste by ursodeoxycholic acid, the inclusive agent (host). The molecular structure of the extracted lycopene was then confirmed by (1) HNMR and its purity was evaluated using high-performance liquid chromatography and UV-Vis spectrophotometry methods, in comparison with a standard product. The results indicated that the proposed separation method was very promising and could be used for the extraction and purification of lycopene from tomato paste. PMID:24111697

  17. Extracting Communities from Complex Networks by the k-Dense Method

    NASA Astrophysics Data System (ADS)

    Saito, Kazumi; Yamada, Takeshi; Kazama, Kazuhiro

    To understand the structural and functional properties of large-scale complex networks, it is crucial to efficiently extract a set of cohesive subnetworks as communities. There have been proposed several such community extraction methods in the literature, including the classical k-core decomposition method and, more recently, the k-clique based community extraction method. The k-core method, although computationally efficient, is often not powerful enough for uncovering a detailed community structure and it produces only coarse-grained and loosely connected communities. The k-clique method, on the other hand, can extract fine-grained and tightly connected communities but requires a substantial amount of computational load for large-scale complex networks. In this paper, we present a new notion of a subnetwork called k-dense, and propose an efficient algorithm for extracting k-dense communities. We applied our method to the three different types of networks assembled from real data, namely, from blog trackbacks, word associations and Wikipedia references, and demonstrated that the k-dense method could extract communities almost as efficiently as the k-core method, while the qualities of the extracted communities are comparable to those obtained by the k-clique method.

  18. Solvent extraction of lanthanoid picrates with crown ethers: preferential sandwich complexation and unique cation selectivities

    SciTech Connect

    Nakagawa, K.; Okada, S.; Inoue, Y.; Tai, A.; Hakushi, T.

    1988-11-15

    Quantitative solvent extractions of aqueous lanthanoid picrates with 15-crown-5 and 18-crown-6 were conducted at low ionic strength in the absence of background salts. An overwhelming preference for the sandwich complexation and unique cation selectivities were observed. The peak extraction constants were found for samarium with 15-crown-5 (1:2 stoichiometry) and for cerium and praseodymium with 18-crown-6 (1:1 and 1:2 stoichiometries, respectively). The facile sandwich complexation and unique cation selectivities are interpreted in terms of the heavy hydration of lanthanoid ions of high charge density.

  19. The behavior and importance of lactic acid complexation in Talspeak extraction systems

    SciTech Connect

    Grimes, Travis S.; Nilsson, Mikael; Nash, Kenneth L.

    2008-07-01

    Advanced partitioning of spent nuclear fuel in the UREX +la process relies on the TALSPEAK process for separation of fission-product lanthanides from trivalent actinides. The classic TALSPEAK utilizes an aqueous medium of both lactic acid and diethylenetriaminepentaacetic acid and the extraction reagent di(2-ethylhexyl)phosphoric acid in an aromatic diluent. In this study, the specific role of lactic acid and the complexes involved in the extraction of the trivalent actinides and lanthanides have been investigated using {sup 14}C-labeled lactic acid. Our results show that lactic acid partitions between the phases in a complex fashion. (authors)

  20. Complexation of silver and dissolved organic matter in soil water extracts.

    PubMed

    Settimio, Lara; McLaughlin, Mike J; Kirby, Jason K; Langdon, Kate A; Janik, Les; Smith, Scott

    2015-04-01

    An important aspect of the behaviour and fate of silver (Ag) in soils is the interaction with dissolved organic matter (DOM). The complexation and strength of binding of Ag(+) with DOM in soil water extracts was examined and modelled based on a range of chemical and quality DOM measurements. Silver ion binding measured by addition of the (110m)Ag radioisotope in addition to a cation exchange resin technique were used to determine strongly complexed Ag in solutions. Silver was found to be up to 70% strongly complexed. The variability in Ag(+) binding by DOM across different soils was closely related (R(2) = 0.8) to the mid-infrared spectra of these extracts. The affinity of Ag(+) for DOM was stronger in solutions containing a greater content of humic and aromatic structures. The ability of Ag(+) to complex with DOM could result in increased mobilisation of this metal in the soil environment. PMID:25660071

  1. POP-ART: thermodynamically correct activated event sampling in complex materials

    NASA Astrophysics Data System (ADS)

    Chubynsky, M. V.; Vocks, Henk; Mousseau, Normand; Barkema, G. T.

    2006-03-01

    Dynamics of complex systems with a rugged energy landscape can be represented as a sequence of rare activated events during which the system jumps between different potential energy minima. The activation-relaxation technique (ART) [1] is an efficient method of sampling such events; however, because of an unknown bias in selecting these events it cannot easily provide thermodynamical information. We present a modification of ART, the properly obeying probability ART (POP-ART) [2]. POP-ART combines short molecular dynamics runs with ART-like activated moves, with an additional accept/reject step designed to satisfy detailed balance and thus reproduce correct thermodynamics. Both correctness and efficiency of the method have been tested using a variety of systems. We mention briefly some ways of extending the approach to obtain correct dynamics as well.[1] G.T. Barkema and N. Mousseau, Phys. Rev. Lett. 77, 4358 (1996)[2] H. Vocks, M.V. Chubynsky, G.T. Barkema and N. Mousseau, J. Chem. Phys., accepted

  2. GENOTOXIC EFFECTS OF COMPLEX MARINE SEDIMENT EXTRACTS ON V79 CHINESE HAMSTER LUNG FIBROBLASTS

    EPA Science Inventory

    A mammalian in vitro system was used to evaluate the genotoxic potential of two complex environmental samples. ister chromatid exchanges (SCEs) were measured in Chinese hamster V79 lung fibroblast cells, following exposure to whole extracts of sediments collected from a highly co...

  3. Stochastic spontaneous calcium release events trigger premature ventricular complexes by overcoming electrotonic load

    PubMed Central

    Campos, Fernando O.; Shiferaw, Yohannes; Prassl, Anton J.; Boyle, Patrick M.; Vigmond, Edward J.; Plank, Gernot

    2015-01-01

    Aims Premature ventricular complexes (PVCs) due to spontaneous calcium (Ca) release (SCR) events at the cell level can precipitate ventricular arrhythmias. However, the mechanistic link between SCRs and PVC formation remains incompletely understood. The aim of this study was to investigate the conditions under which delayed afterdepolarizations resulting from stochastic subcellular SCR events can overcome electrotonic source–sink mismatch, leading to PVC initiation. Methods and results A stochastic subcellular-scale mathematical model of SCR was incorporated in a realistic model of the rabbit ventricles and Purkinje system (PS). Elevated levels of diastolic sarcoplasmic reticulum Ca2+ (CaSR) were imposed until triggered activity was observed, allowing us to compile statistics on probability, timing, and location of PVCs. At CaSR≥ 1500 µmol/L PVCs originated in the PS. When SCR was incapacitated in the PS, PVCs also emerged in the ventricles, but at a higher CaSR (≥1550 µmol/L) and with longer waiting times. For each model configuration tested, the probability of PVC occurrence increased from 0 to 100% within a well-defined critical CaSR range; this transition was much more abrupt in organ-scale models (∼50 µmol/L CaSR range) than in the tissue strand (∼100 µmol/L) or single-cell (∼450 µmol/L) models. Among PVCs originating in the PS, ∼68% were located near Purkinje-ventricular junctions (<1 mm). Conclusion SCR events overcome source–sink mismatch to trigger PVCs at a critical CaSR threshold. Above this threshold, PVCs emerge due to increased probability and reduced variability in timing of SCR events, leading to significant diastolic depolarization. Sites of lower electronic load, such as the PS, are preferential locations for triggering. PMID:25969391

  4. Heart Rate Deceleration as a Function of Viewing Complex Visual Events in Eighteen-Month-Old Infants.

    ERIC Educational Resources Information Center

    Gilmore, Lowry M.; And Others

    This research project assessed: (1) the practicality of recording heart rate in 18-month-old infants as they watched events filmed on color, silent motion picture films; and (2) the validity and sensitivity of heart rate change as an index of differential attention arousal elicited by changes within and between complex visual events. The research…

  5. Downscaling 20th century flooding events in complex terrain (Switzerland) using the WRF regional climate model

    NASA Astrophysics Data System (ADS)

    Heikkilä, Ulla; Gómez Navarro, Juan Jose; Franke, Jörg; Brönnimann, Stefan; Cattin, Réne

    2016-04-01

    Switzerland has experienced a number of severe precipitation events during the last few decades, such as during the 14-16 November of 2002 or during the 21-22 August of 2005. Both events, and subsequent extreme floods, caused fatalities and severe financial losses, and have been well studied both in terms of atmospheric conditions leading to extreme precipitation, and their consequences [e.g. Hohenegger et al., 2008, Stucki et al., 2012]. These examples highlight the need to better characterise the frequency and severity of flooding in the Alpine area. In a larger framework we will ultimately produce a high-resolution data set covering the entire 20th century to be used for detailed hydrological studies including all atmospheric parameters relevant for flooding events. In a first step, we downscale the aforementioned two events of 2002 and 2005 to assess the model performance regarding precipitation extremes. The complexity of the topography in the Alpine area demands high resolution datasets. To achieve a sufficient detail in resolution we employ the Weather Research and Forecasting regional climate model (WRF). A set of 4 nested domains is used with a 2-km resolution horizontal resolution over Switzerland. The NCAR 20th century reanalysis (20CR) with a horizontal resolution of 2.5° serves as boundary condition [Compo et al., 2011]. First results of the downscaling the 2002 and 2005 extreme precipitation events show that, compared to station observations provided by the Swiss Meteorological Office MeteoSwiss, the model strongly underestimates the strength of these events. This is mainly due to the coarse resolution of the 20CR data, which underestimates the moisture fluxes during these events. We tested driving WRF with the higher-resolved NCEP reanalysis and found a significant improvement in the amount of precipitation of the 2005 event. In a next step we will downscale the precipitation and wind fields during a 6-year period 2002-2007 to investigate and

  6. Molecular events underlying maggot extract promoted rat in vivo and human in vitro skin wound healing.

    PubMed

    Li, Pei-Nan; Li, Hong; Zhong, Li-Xia; Sun, Yuan; Yu, Li-Jun; Wu, Mo-Li; Zhang, Lin-Lin; Kong, Qing-You; Wang, Shou-Yu; Lv, De-Cheng

    2015-01-01

    Maggot extracts promote wound healing, but their bioactive part(s) and molecular effects on the regenerating tissues/cells remain largely unclear. These issues are addressed here by treating rat skin wounds, human keratinocyte line/HaCat and fibroblasts with maggot secretion/excretion, and the extracts of maggots without and with secretion/excretion. The wound closure rates, cell proliferation activities, and statuses of wound healing-related signaling pathways (STAT3, Notch1, Wnt2, NF-κB, and TGF-beta/Smad3) and their downstream gene expression (c-Myc, cyclin D1, and VEGF) are evaluated by multiple approaches. The results reveal that the maggot extracts, especially the one from the maggots without secretion/excretion, show the best wound healing-promoting effects in terms of quicker wound closure rates and more rapid growth of keratinocytes and fibroblasts. Of the five signaling pathways checked, the ones mediated by TGF-beta/Smad3, and STAT3 are activated in the untreated wounds and become further enhanced by the maggot extracts, accompanied with c-Myc, VEGF, and cyclin D1 up-regulation. Our results thus show (1) that both body extract and secretion/excretion of maggots contain favorable wound healing elements and (2) that the enhancement of TGF-beta/Smad3 and STAT3 signaling activities may be the main molecular effects of maggot extracts on the wound tissues. PMID:25469773

  7. Complex networks identify spatial patterns of extreme rainfall events of the South American Monsoon System

    NASA Astrophysics Data System (ADS)

    Boers, Niklas; Bookhagen, Bodo; Marwan, Norbert; Kurths, Jürgen; Marengo, José

    2013-08-01

    We investigate the spatial characteristics of extreme rainfall synchronicity of the South American Monsoon System (SAMS) by means of Complex Networks (CN). By introducing a new combination of CN measures and interpreting it in a climatic context, we investigate climatic linkages and classify the spatial characteristics of extreme rainfall synchronicity. Although our approach is based on only one variable (rainfall), it reveals the most important features of the SAMS, such as the main moisture pathways, areas with frequent development of Mesoscale Convective Systems (MCS), and the major convergence zones. In addition, our results reveal substantial differences between the spatial structures of rainfall synchronicity above the 90th and above the 95th percentiles. Most notably, events above the 95th percentile contribute stronger to MCS in the La Plata Basin.

  8. Density functional theory investigations of the trivalent lanthanide and actinide extraction complexes with diglycolamides.

    PubMed

    Wang, Cong-Zhi; Lan, Jian-Hui; Wu, Qun-Yan; Zhao, Yu-Liang; Wang, Xiang-Ke; Chai, Zhi-Fang; Shi, Wei-Qun

    2014-06-21

    At present, designing novel ligands for efficient actinide extraction in spent nuclear fuel reprocessing is extremely challenging due to the complicated chemical behaviors of actinides, the similar chemical properties of minor actinides (MA) and lanthanides, and the vulnerability of organic ligands in acidic radioactive solutions. In this work, a quantum chemical study on Am(III), Cm(III) and Eu(III) complexes with N,N,N',N'-tetraoctyl diglycolamide (TODGA) and N,N'-dimethyl-N,N'-diheptyl-3-oxapentanediamide (DMDHOPDA) has been carried out to explore the extraction behaviors of trivalent actinides (An) and lanthanides (Ln) with diglycolamides from acidic media. It has been found that in the 1 : 1 (ligand : metal) and 2 : 1 stoichiometric complexes, the carbonyl oxygen atoms have stronger coordination ability than the ether oxygen atoms, and the interactions between metal cations and organic ligands are substantially ionic. The neutral ML(NO3)3 (M = Am, Cm, Eu) complexes seem to be the most favorable species in the extraction process, and the predicted relative selectivities are in agreement with experimental results, i.e., the diglycolamide ligands have slightly higher selectivity for Am(III) over Eu(III). Such a thermodynamical priority is probably caused by the higher stabilities of Eu(III) hydration species and Eu(III)-L complexes in aqueous solution compared to their analogues. In addition, our thermodynamic analysis from water to organic medium confirms that DMDHOPDA has higher extraction ability for the trivalent actinides and lanthanides than TODGA, which may be due to the steric hindrance of the bulky alkyl groups of TODGA ligands. This work might provide an insight into understanding the origin of the actinide selectivity and a theoretical basis for designing highly efficient extractants for actinide separation. PMID:24769618

  9. Words Analysis of Online Chinese News Headlines about Trending Events: A Complex Network Perspective

    PubMed Central

    Li, Huajiao; Fang, Wei; An, Haizhong; Huang, Xuan

    2015-01-01

    Because the volume of information available online is growing at breakneck speed, keeping up with meaning and information communicated by the media and netizens is a new challenge both for scholars and for companies who must address public relations crises. Most current theories and tools are directed at identifying one website or one piece of online news and do not attempt to develop a rapid understanding of all websites and all news covering one topic. This paper represents an effort to integrate statistics, word segmentation, complex networks and visualization to analyze headlines’ keywords and words relationships in online Chinese news using two samples: the 2011 Bohai Bay oil spill and the 2010 Gulf of Mexico oil spill. We gathered all the news headlines concerning the two trending events in the search results from Baidu, the most popular Chinese search engine. We used Simple Chinese Word Segmentation to segment all the headlines into words and then took words as nodes and considered adjacent relations as edges to construct word networks both using the whole sample and at the monthly level. Finally, we develop an integrated mechanism to analyze the features of words’ networks based on news headlines that can account for all the keywords in the news about a particular event and therefore track the evolution of news deeply and rapidly. PMID:25807376

  10. Words analysis of online Chinese news headlines about trending events: a complex network perspective.

    PubMed

    Li, Huajiao; Fang, Wei; An, Haizhong; Huang, Xuan

    2015-01-01

    Because the volume of information available online is growing at breakneck speed, keeping up with meaning and information communicated by the media and netizens is a new challenge both for scholars and for companies who must address public relations crises. Most current theories and tools are directed at identifying one website or one piece of online news and do not attempt to develop a rapid understanding of all websites and all news covering one topic. This paper represents an effort to integrate statistics, word segmentation, complex networks and visualization to analyze headlines' keywords and words relationships in online Chinese news using two samples: the 2011 Bohai Bay oil spill and the 2010 Gulf of Mexico oil spill. We gathered all the news headlines concerning the two trending events in the search results from Baidu, the most popular Chinese search engine. We used Simple Chinese Word Segmentation to segment all the headlines into words and then took words as nodes and considered adjacent relations as edges to construct word networks both using the whole sample and at the monthly level. Finally, we develop an integrated mechanism to analyze the features of words' networks based on news headlines that can account for all the keywords in the news about a particular event and therefore track the evolution of news deeply and rapidly. PMID:25807376

  11. Sentiment Diffusion of Public Opinions about Hot Events: Based on Complex Network.

    PubMed

    Hao, Xiaoqing; An, Haizhong; Zhang, Lijia; Li, Huajiao; Wei, Guannan

    2015-01-01

    To study the sentiment diffusion of online public opinions about hot events, we collected people's posts through web data mining techniques. We calculated the sentiment value of each post based on a sentiment dictionary. Next, we divided those posts into five different orientations of sentiments: strongly positive (P), weakly positive (p), neutral (o), weakly negative (n), and strongly negative (N). These sentiments are combined into modes through coarse graining. We constructed sentiment mode complex network of online public opinions (SMCOP) with modes as nodes and the conversion relation in chronological order between different types of modes as edges. We calculated the strength, k-plex clique, clustering coefficient and betweenness centrality of the SMCOP. The results show that the strength distribution obeys power law. Most posts' sentiments are weakly positive and neutral, whereas few are strongly negative. There are weakly positive subgroups and neutral subgroups with ppppp and ooooo as the core mode, respectively. Few modes have larger betweenness centrality values and most modes convert to each other with these higher betweenness centrality modes as mediums. Therefore, the relevant person or institutes can take measures to lead people's sentiments regarding online hot events according to the sentiment diffusion mechanism. PMID:26462230

  12. Sentiment Diffusion of Public Opinions about Hot Events: Based on Complex Network

    PubMed Central

    Hao, Xiaoqing; An, Haizhong; Zhang, Lijia; Li, Huajiao; Wei, Guannan

    2015-01-01

    To study the sentiment diffusion of online public opinions about hot events, we collected people’s posts through web data mining techniques. We calculated the sentiment value of each post based on a sentiment dictionary. Next, we divided those posts into five different orientations of sentiments: strongly positive (P), weakly positive (p), neutral (o), weakly negative (n), and strongly negative (N). These sentiments are combined into modes through coarse graining. We constructed sentiment mode complex network of online public opinions (SMCOP) with modes as nodes and the conversion relation in chronological order between different types of modes as edges. We calculated the strength, k-plex clique, clustering coefficient and betweenness centrality of the SMCOP. The results show that the strength distribution obeys power law. Most posts’ sentiments are weakly positive and neutral, whereas few are strongly negative. There are weakly positive subgroups and neutral subgroups with ppppp and ooooo as the core mode, respectively. Few modes have larger betweenness centrality values and most modes convert to each other with these higher betweenness centrality modes as mediums. Therefore, the relevant person or institutes can take measures to lead people’s sentiments regarding online hot events according to the sentiment diffusion mechanism. PMID:26462230

  13. A Validation System for the Complex Event Processing Directives of the ATLAS Shifter Assistant Tool

    NASA Astrophysics Data System (ADS)

    Santos, A.; Anders, G.; Avolio, G.; Kazarov, A.; Lehmann Miotto, G.; Soloviev, I.

    2015-12-01

    Complex Event Processing (CEP) is a methodology that combines data from many sources in order to identify events or patterns that need particular attention. It has gained a lot of momentum in the computing world in the past few years and is used in ATLAS to continuously monitor the behaviour of the data acquisition system, to trigger corrective actions and to guide the experiment's operators. This technology is very powerful, if experts regularly insert and update their knowledge about the system's behaviour into the CEP engine. Nevertheless, writing or modifying CEP rules is not trivial since the used programming paradigm is quite different with respect to what developers are normally familiar with. In order to help experts verify that the rules work as expected, we have thus developed a complete testing and validation environment. This system consists of three main parts: the first is the data reader from existing storage of all relevant data streams that are produced during data taking, the second is a playback tool that allows to re-inject data of specific data taking sessions from the past into the CEP engine, and the third is a reporting tool that shows the output that the rules loaded into the engine would have produced in the live system. In this paper we describe the design and implementation of this validation system, highlight its strengths and shortcomings and indicate how such a system could be reused in similar projects.

  14. Preparation and characterization of standardized pomegranate extract-phospholipid complex as an effective drug delivery tool

    PubMed Central

    Vora, Amisha Kamlesh; Londhe, Vaishali Y.; Pandita, Nancy S.

    2015-01-01

    Punicalagins, a pair of anomeric ellagitannins, present in Punica granatum (Pomegranates) are known to possess excellent antioxidant activity in vitro, but poor oral bioavailability. The reasons cited for poor bioavailability are their large molecular size, poor lipophilicity, and degradation by colonic microflora into less active metabolites. The objective of the present research work was to complex the standardized pomegranate extract (SPE) with phospholipid to formulate standardized pomegranate extract-phospholipid complex (SPEPC), characterize it and check its permeability through an ex vivo everted gut sac experiment. SPEPC was prepared by mixing SPE (30% punicalagins) and soya phosphatidylcholine (PC) in 1:1 v/v mixture of methanol and dioxane and spray-drying the mixture. The complex was characterized by infrared spectroscopy, differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy. It was evaluated for its octanol solubility, dissolution, and permeability by everted the gut sac technique. The characterization methods confirmed the formation of complex. Increased n-octanol solubility of the complex proved its increased lipophilicity. Dissolution studies revealed that the phospholipid covering may prevent the punicalagins to be released in gastro-intestinal tract, thus preventing their colonic microbial degradation. SPEPC showed better apparent permeability than SPE in an everted gut sac technique. Hence, it could be concluded that phospholipid complex of SPE may be of potential use in increasing the permeability and hence the bioavailability of punicalagins. PMID:25878977

  15. Preparation and characterization of standardized pomegranate extract-phospholipid complex as an effective drug delivery tool.

    PubMed

    Vora, Amisha Kamlesh; Londhe, Vaishali Y; Pandita, Nancy S

    2015-01-01

    Punicalagins, a pair of anomeric ellagitannins, present in Punica granatum (Pomegranates) are known to possess excellent antioxidant activity in vitro, but poor oral bioavailability. The reasons cited for poor bioavailability are their large molecular size, poor lipophilicity, and degradation by colonic microflora into less active metabolites. The objective of the present research work was to complex the standardized pomegranate extract (SPE) with phospholipid to formulate standardized pomegranate extract-phospholipid complex (SPEPC), characterize it and check its permeability through an ex vivo everted gut sac experiment. SPEPC was prepared by mixing SPE (30% punicalagins) and soya phosphatidylcholine (PC) in 1:1 v/v mixture of methanol and dioxane and spray-drying the mixture. The complex was characterized by infrared spectroscopy, differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy. It was evaluated for its octanol solubility, dissolution, and permeability by everted the gut sac technique. The characterization methods confirmed the formation of complex. Increased n-octanol solubility of the complex proved its increased lipophilicity. Dissolution studies revealed that the phospholipid covering may prevent the punicalagins to be released in gastro-intestinal tract, thus preventing their colonic microbial degradation. SPEPC showed better apparent permeability than SPE in an everted gut sac technique. Hence, it could be concluded that phospholipid complex of SPE may be of potential use in increasing the permeability and hence the bioavailability of punicalagins. PMID:25878977

  16. Synergy in Extraction System Chemistry: Combining Configurational Entropy, Film Bending, and Perturbation of Complexation.

    PubMed

    Rey, J; Dourdain, S; Berthon, L; Jestin, J; Pellet-Rostaing, S; Zemb, T

    2015-06-30

    Iron-uranium selectivity in liquid-liquid extraction depends not only on the mole fraction of extractants, but also on the nature of the diluent used, even if the diluent has no complexation interaction with the extracted ions. Modeling strong nonlinearity is difficult to parametrize without a large number of parameters, interpreted as "apparent constants". We determine in this paper the synergy curve versus mole fraction of HDEHP-TOPO (di(2-ethylexyl) phosphoric acid/tri-n-octyl phosphine oxide) and compare the free energy of aggregation to the free energy of extraction in various diluents. There is always a concomitant maximum of the two quantities, but with a gradual influence on intensity. The diluent is wetting the chains of the reverse aggregates responsible of the extraction. We show here that the intensity of the unexplained synergy peak is strongly dependent on the "penetrating" or "nonpenetrating" nature of the diluent. This experimental determination allows us to attribute the synergy to a combination of entropic effects favoring extraction, opposed to perturbation of the first coordination sphere by penetration as well as surfactant film bending energy. PMID:26053416

  17. Using Complex Event Processing (CEP) and vocal synthesis techniques to improve comprehension of sonified human-centric data

    NASA Astrophysics Data System (ADS)

    Rimland, Jeff; Ballora, Mark

    2014-05-01

    The field of sonification, which uses auditory presentation of data to replace or augment visualization techniques, is gaining popularity and acceptance for analysis of "big data" and for assisting analysts who are unable to utilize traditional visual approaches due to either: 1) visual overload caused by existing displays; 2) concurrent need to perform critical visually intensive tasks (e.g. operating a vehicle or performing a medical procedure); or 3) visual impairment due to either temporary environmental factors (e.g. dense smoke) or biological causes. Sonification tools typically map data values to sound attributes such as pitch, volume, and localization to enable them to be interpreted via human listening. In more complex problems, the challenge is in creating multi-dimensional sonifications that are both compelling and listenable, and that have enough discrete features that can be modulated in ways that allow meaningful discrimination by a listener. We propose a solution to this problem that incorporates Complex Event Processing (CEP) with speech synthesis. Some of the more promising sonifications to date use speech synthesis, which is an "instrument" that is amenable to extended listening, and can also provide a great deal of subtle nuance. These vocal nuances, which can represent a nearly limitless number of expressive meanings (via a combination of pitch, inflection, volume, and other acoustic factors), are the basis of our daily communications, and thus have the potential to engage the innate human understanding of these sounds. Additionally, recent advances in CEP have facilitated the extraction of multi-level hierarchies of information, which is necessary to bridge the gap between raw data and this type of vocal synthesis. We therefore propose that CEP-enabled sonifications based on the sound of human utterances could be considered the next logical step in human-centric "big data" compression and transmission.

  18. Hydrogen-Bound Complexes of Tropolone: Gateways for the Interrogation of Multiple Proton-Transfer Events

    NASA Astrophysics Data System (ADS)

    Nemchick, Deacon J.; Chew, Kathryn; Wolff, John E.; Vaccaro, Patrick H.

    2011-06-01

    Tropolone (TrOH) serves as a model system for the study of coherent proton-transfer processes, where a potential barrier of finite height hinders the symmetric exchange of a lone hydron between hydroxylic (proton-donating) and ketonic (proton-accepting) oxygen centers. This talk will discuss ongoing efforts to build upon the known structural and dynamical properties of tropolone so as to explore related multiple proton-transfer events that are mediated by successive formation and breaking of several hydrogen bonds. Of particular interest are weakly-bound complexes created in situ under ``cold'' molecular-beam conditions by docking amphoteric ligands (e.g., HF and HCOOH) into the reaction cleft of the TrOH substrate. Such species have the tantalizing possibility of undergoing double proton transfer, with resulting tunneling-induced bifurcation of rovibronic features reflecting the intrinsic vibrational and/or electronic specificity of the attendant unimolecular transformation. Spectroscopic studies of several hydrogen-bound TrOH complexes through use of the richly structured tilde{A}1B2-tilde{X}1A1 (π *← π ) absorption system will be presented, with complementary quantum-chemical calculations serving to guide the assignment and interpretation of observed spectral patterns. L. A. Burns, D. Murdock, and P. H. Vaccaro, Mol. Phys., 108, 1171 (2010).

  19. Modeling of fermentation with continuous lactic acid removal by extraction utilizing reversible chemical complexation

    SciTech Connect

    Dai, Y.; King, C.J.

    1995-07-01

    Extractive fermentation is a technique that can be used to reduce end-product inhibition by removing fermentation products in situ or in an external recycle loop. A model is presented for fermentation with continuous lactic acid removal by extraction utilizing chemical complexation. The model is formulated considering the kinetics of cell growth and the equilibrium distribution of lactic acid between aqueous and organic phases. Simulations have been carried out for different sets of operating conditions. The choice of pH balances faster kinetics at higher pH against lower product concentrations in the solvent and more difficult regeneration. A key need is for liquid extractants or solid sorbents combining stronger uptake ability with economical regeneration and satisfactory biocompatibility.

  20. Collaborative-Comparison Learning for Complex Event Detection Using Distributed Hierarchical Graph Neuron (DHGN) Approach in Wireless Sensor Network

    NASA Astrophysics Data System (ADS)

    Muhamad Amin, Anang Hudaya; Khan, Asad I.

    Research trends in existing event detection schemes using Wireless Sensor Network (WSN) have mainly focused on routing and localisation of nodes for optimum coordination when retrieving sensory information. Efforts have also been put in place to create schemes that are able to provide learning mechanisms for event detection using classification or clustering approaches. These schemes entail substantial communication and computational overheads owing to the event-oblivious nature of data transmissions. In this paper, we present an event detection scheme that has the ability to distribute detection processes over the resource-constrained wireless sensor nodes and is suitable for events with spatio-temporal characteristics. We adopt a pattern recognition algorithm known as Distributed Hierarchical Graph Neuron (DHGN) with collaborative-comparison learning for detecting critical events in WSN. The scheme demonstrates good accuracy for binary classification and offers low-complexity and high-scalability in terms of its processing requirements.

  1. Radiochemical data collected on events from which radioactivity escaped beyond the borders of the Nevada test range complex. [NONE

    SciTech Connect

    Hicks, H.G.

    1981-02-12

    This report identifies all nuclear events in Nevada that are known to have sent radioactivity beyond the borders of the test range complex. There have been 177 such tests, representing seven different types: nuclear detonations in the atmosphere, nuclear excavation events, nuclear safety events, underground nuclear events that inadvertently seeped or vented to the atmosphere, dispersion of plutonium and/or uranium by chemical high explosives, nuclear rocket engine tests, and nuclear ramjet engine tests. The source term for each of these events is given, together with the data base from which it was derived (except where the data are classified). The computer programs used for organizing and processing the data base and calculating radionuclide production are described and included, together with the input and output data and details of the calculations. This is the basic formation needed to make computer modeling studies of the fallout from any of these 177 events.

  2. Green synthesis of ZnO nanoparticles via complex formation by using Curcuma longa extract

    NASA Astrophysics Data System (ADS)

    Fatimah, Is; Yudha, Septian P.; Mutiara, Nur Afisa Lintang

    2016-02-01

    Synthesis of ZnO nanoparticles(NPs) were conducted via Zn(II) complex formation by using Curcuma longa extract as template. Curcuma longa extract has the ability to form zinc ions complex with curcumin as ligating agent. Study on synthesis was conducted by monitoring thermal degradation of the material. Successful formation of zinc oxide nanoparticles was confirmed by employing x-ray diffraction, surface area analysis and transmission electron microscopy(TEM) studies. From the XRD analysis it is denoted that ZnO in hexagonal wurtzite phase was formed and particle size was varied as varied temperature. The data are also confirmed by TEM analysis which shows the particle sie at the range 20-80nm. The NPs exhibited excelent photocatalytic activity for methylene blue degradation and also significant antibacterial activity for Eschericia coli. The activity in methylene blue degradation was also confirmed from fast chemical oxygen demand (COD) reduction.

  3. Complex eigenvalue extraction in NASTRAN by the tridiagonal reduction (FEER) method

    NASA Technical Reports Server (NTRS)

    Newman, M.; Mann, F. I.

    1977-01-01

    An extension of the Tridiagonal Reduction (FEER) method to complex eigenvalue analysis in NASTRAN is described. As in the case of real eigenvalue analysis, the eigensolutions closest to a selected point in the eigenspectrum are extracted from a reduced, symmetric, tridiagonal eigenmatrix whose order is much lower than that of the full size problem. The reduction process is effected automatically, and thus avoids the arbitrary lumping of masses and other physical quantities at selected grid points. The statement of the algebraic eigenvalue problem admits mass, damping and stiffness matrices which are unrestricted in character, i.e., they may be real, complex, symmetric or unsymmetric, singular or non-singular.

  4. Multiple biological complex of alkaline extract of the leaves of Sasa senanensis Rehder.

    PubMed

    Sakagami, Hiroshi; Zhou, Li; Kawano, Michiyo; Thet, May Maw; Tanaka, Shoji; Machino, Mamoru; Amano, Shigeru; Kuroshita, Reina; Watanabe, Shigeru; Chu, Qing; Wang, Qin-Tao; Kanamoto, Taisei; Terakubo, Shigemi; Nakashima, Hideki; Sekine, Keisuke; Shirataki, Yoshiaki; Zhang, Chang-Hao; Uesawa, Yoshihiro; Mohri, Kiminori; Kitajima, Madoka; Oizumi, Hiroshi; Oizumi, Takaaki

    2010-01-01

    Previous studies have shown anti-inflammatory potential of alkaline extract of the leaves of Sasa senanensis Rehder (SE). The aim of the present study was to clarity the molecular entity of SE, using various fractionation methods. SE inhibited the production of nitric oxide (NO), but not tumour necrosis factor-α by lipopolysaccharide (LPS)-stimulated mouse macrophage-like cells. Lignin carbohydrate complex prepared from SE inhibited the NO production to a comparable extent with SE, whereas chlorophyllin was more active. On successive extraction with organic solvents, nearly 90% of SE components, including chlorophyllin, were recovered from the aqueous layer. Anti-HIV activity of SE was comparable with that of lignin-carbohydrate complex, and much higher than that of chlorophyllin and n-butanol extract fractions. The CYP3A inhibitory activity of SE was significantly lower than that of grapefruit juice and chlorophyllin. Oral administration of SE slightly reduced the number of oral bacteria. When SE was applied to HPLC, nearly 70% of SE components were eluted as a single peak. These data suggest that multiple components of SE may be associated with each other in the native state or after extraction with alkaline solution. PMID:20952742

  5. Extraction of pyridines into fluorous solvents based on hydrogen bond complex formation with carboxylic acid receptors.

    PubMed

    O'Neal, Kristi L; Geib, Steven; Weber, Stephen G

    2007-04-15

    A molecular receptor embedded in a 'poor-solvent' receiving phase, such as a fluorous phase, should offer the ideal medium for selective extraction and sensing. The limited solubility of most solutes in fluorous phases enhances selectivity by reducing the extraction of unwanted matrix components. Thus, receptor-doped fluorous phases may be ideal extraction media. Unfortunately, sufficient data do not exist to judge the capability of this approach. The solubilities of very few nonfluorous solutes are known. As far as we are aware, such important quantities as the strength of a hydrogen bond in a fluorous environment are not known. Thus, it is currently impossible to predict whether a particular receptor/solute complex based on a particular set of noncovalent interactions will provide enough thermodynamic stabilization to extract the solute into the fluorous phase. In this work, fluorous carboxylic acids (a carboxylic acid-terminated perfluoropolypropylene oxide called Krytox and perfluorodecanoic acid (PFDA)) were used as receptors and substituted pyridines as solutes to show that the fluorous receptor dramatically enhances the liquid-liquid extraction of the polar substrates from chloroform into perfluorohexanes. The method of continuous variations was used to determine the receptor-pyridine complex stoichiometry of 3:1. The free energies of formation of the 3:1 complexes from one pyridine and 3/2 H-bonded cyclic dimers of the fluorous carboxylic acid are -30.4 (Krytox) and -37.3 kJ mol-1 (PFDA). The free energy required to dissociate the dimer in perfluorohexanes is +16.5 kJ mol-1 (Krytox). The crystal structure of the complex showed a 1:1 stoichiometry with a mixed strong-weak hydrogen-bonded motif. Based on the stoichiometry, crystal structure, and UV and IR spectroscopic shifts, we propose that the 3:1 complex has four hydrogen bonds and the carboxylic acid transfers a proton to pyridine. The resulting pyridinium carboxylate N+H-O- hydrogen bond is accompanied

  6. Lipophilic ternary complexes in liquid-liquid extraction of trivalent lanthanides

    SciTech Connect

    Lumetta, Gregg J.; Levitskaia, Tatiana G.; Latesky, Stanley; Henderson, Renesha V.; Edwards, Emilio A.; Braley, Jenifer C.; Sinkov, Sergey I.

    2012-03-01

    The formation of ternary complexes between lanthanide ions [Nd(III) or Eu(III)], octyl(phenyl)-N,N-diisobutyl-carbamoylmethylphosphine oxide (CMPO), and bis-(2-ethylhexyl)phosphoric acid (HDEHP) was probed by liquid-liquid extraction and spectroscopic techniques. Equilibrium modeling of data for the extraction of Nd(III) or Eu(III) from lactic acid media into n-dodecane solutions of CMPO and HDEHP indicates the predominant extracted species are of the type [Ln(AHA){sub 2}(A)] and [Ln(CMPO)(AHA){sub 2}(A)], where Ln = Nd or Eu and A represents the DEHP{sup -} anion. FTIR (for both Eu and Nd) and visible spectrophotometry (in the case of Nd) indicate the formation of the [Ln(CMPO)(A){sup 3}] complexes when CMPO is added to n-dodecane solutions of the LnA{sub 3} compounds. Both techniques indicate a stronger propensity of CMPO to complex Nd(III) versus Eu(III).

  7. Complex tool sets for honey extraction among chimpanzees in Loango National Park, Gabon.

    PubMed

    Boesch, Christophe; Head, Josephine; Robbins, Martha M

    2009-06-01

    Homo faber was once proposed as a label for humans specifically to highlight their unique propensity for tool use. However, new observations on complex tool use by the chimpanzees of Loango National Park, Gabon, expand our knowledge about tool-using abilities in Pan troglodytes. Chimpanzees in Loango, when using tools to extract honey from three types of bee nests, were observed to regularly use three- to five-element tool sets. In other words, different types of tools were used sequentially to access a single food source. Such tool sets included multi-function tools that present typical wear for two distinct uses. In addition, chimpanzees exploited underground bee nests and used ground-perforating tools to locate nest chambers that were not visible from the ground surface. These new observations concur with others from Central African chimpanzees to highlight the importance of honey extraction in arguments favoring the emergence of complex tool use in hominoids, including different tool types, expanded tool sets, multifunction tools, and the exploitation of underground resources. This last technique requires sophisticated cognitive abilities concerning unseen objects. A sequential analysis reveals a higher level of complexity in honey extraction than previously proposed for nut cracking or hunting tools, and compares with some technologies attributed to early hominins from the Early and Middle Stone Age. A better understanding of similarities in human and chimpanzee tool use will allow for a greater understanding of tool-using skills that are uniquely human. PMID:19457542

  8. Application of the EVEX resource to event extraction and network construction: Shared Task entry and result analysis

    PubMed Central

    2015-01-01

    Background Modern methods for mining biomolecular interactions from literature typically make predictions based solely on the immediate textual context, in effect a single sentence. No prior work has been published on extending this context to the information automatically gathered from the whole biomedical literature. Thus, our motivation for this study is to explore whether mutually supporting evidence, aggregated across several documents can be utilized to improve the performance of the state-of-the-art event extraction systems. In this paper, we describe our participation in the latest BioNLP Shared Task using the large-scale text mining resource EVEX. We participated in the Genia Event Extraction (GE) and Gene Regulation Network (GRN) tasks with two separate systems. In the GE task, we implemented a re-ranking approach to improve the precision of an existing event extraction system, incorporating features from the EVEX resource. In the GRN task, our system relied solely on the EVEX resource and utilized a rule-based conversion algorithm between the EVEX and GRN formats. Results In the GE task, our re-ranking approach led to a modest performance increase and resulted in the first rank of the official Shared Task results with 50.97% F-score. Additionally, in this paper we explore and evaluate the usage of distributed vector representations for this challenge. In the GRN task, we ranked fifth in the official results with a strict/relaxed SER score of 0.92/0.81 respectively. To try and improve upon these results, we have implemented a novel machine learning based conversion system and benchmarked its performance against the original rule-based system. Conclusions For the GRN task, we were able to produce a gene regulatory network from the EVEX data, warranting the use of such generic large-scale text mining data in network biology settings. A detailed performance and error analysis provides more insight into the relatively low recall rates. In the GE task we

  9. Complex Negative Regulation of TLR9 by Multiple Proteolytic Cleavage Events.

    PubMed

    Sinha, Siddhartha S; Cameron, Jody; Brooks, James C; Leifer, Cynthia A

    2016-08-15

    TLR9 is an innate immune receptor important for recognizing DNA of host and foreign origin. A mechanism proposed to prevent excessive response to host DNA is the requirement for proteolytic cleavage of TLR9 in endosomes to generate a mature form of the receptor (TLR9(471-1032)). We previously described another cleavage event in the juxtamembrane region of the ectodomain that generated a dominant-negative form of TLR9. Thus, there are at least two independent cleavage events that regulate TLR9. In this study, we investigated whether an N-terminal fragment of TLR9 could be responsible for regulation of the mature or negative-regulatory form. We show that TLR9(471-1032), corresponding to the proteolytically cleaved form, does not function on its own. Furthermore, activity is not rescued by coexpression of the N-terminal fragment (TLR9(1-440)), inclusion of the hinge region (TLR9(441-1032)), or overexpression of UNC93B1, the last of which is critical for trafficking and cleavage of TLR9. TLR9(1-440) coimmunoprecipitates with full-length TLR9 and TLR9(471-1032) but does not rescue the native glycosylation pattern; thus, inappropriate trafficking likely explains why TLR9(471-1032) is nonfunctional. Lastly, we show that TLR9(471-1032) is also a dominant-negative regulator of TLR9 signaling. Together, these data provide a new perspective on the complexity of TLR9 regulation by proteolytic cleavage and offer potential ways to inhibit activity through this receptor, which may dampen autoimmune inflammation. PMID:27421483

  10. Aerogel Keystones: Extraction Of Complete Hypervelocity Impact Events From Aerogel Collectors

    SciTech Connect

    Westphal, A J; Snead, C; Butterworth, A; Graham, G A; Bradley, J; Bajt, S; Grant, P G; Bench, G; Brennan, S; Piannetta, P

    2003-11-07

    In January 2006, the Stardust mission will return the first samples from a solid solar-system body since Apollo, and the first samples of contemporary interstellar dust ever collected. Although sophisticated laboratory instruments exist for the analysis of Stardust samples, techniques for the recovery of particles and particle residues from aerogel collectors remain primitive. Here we describe our recent progress in developing techniques for extracting small volumes of aerogel, which we have called ''keystones,'' which completely contain particle impacts but minimize the damage to the surrounding aerogel collector. These keystones can be fixed to custom-designed micromachined silicon fixtures (so-called ''microforklifts''). In this configuration the samples are self-supporting, which can be advantageous in situations in which interference from a supporting substrate is undesirable. The keystones may also be extracted and placed onto a substrate without a fixture. We have also demonstrated the capability of homologously crushing these unmounted keystones for analysis techniques which demand flat samples.

  11. Strategy for introduction of rainwater management facility considering rainfall event applied on new apartment complex

    NASA Astrophysics Data System (ADS)

    KIM, H.; Lee, D. K.; Yoo, S.

    2014-12-01

    As regional torrential rains become frequent due to climate change, urban flooding happens very often. That is why it is necessary to prepare for integrated measures against a wide range of rainfall. This study proposes introduction of effective rainwater management facilities to maximize the rainwater runoff reductions and recover natural water circulation for unpredictable extreme rainfall in apartment complex scale. The study site is new apartment complex in Hanam located in east of Seoul, Korea. It has an area of 7.28ha and is analysed using the EPA-SWMM and STORM model. First, it is analyzed that green infrastructure(GI) had efficiency of flood reduction at the various rainfall events and soil characteristics, and then the most effective value of variables are derived. In case of rainfall event, Last 10 years data of 15 minutes were used for analysis. A comparison between A(686mm rainfall during 22days) and B(661mm/4days) knew that soil infiltration of A is 17.08% and B is 5.48% of the rainfall. Reduction of runoff after introduction of the GI of A is 24.76% and B is 6.56%. These results mean that GI is effective to small rainfall intensity, and artificial rainwater retarding reservoir is needed at extreme rainfall. Second, set of target year is conducted for the recovery of hydrological cycle at the predevelopment. And an amount of infiltration, evaporation, surface runoff of the target year and now is analysed on the basis of land coverage, and an arrangement of LID facilities. Third, rainwater management scenarios are established and simulated by the SWMM-LID. Rainwater management facilities include GI(green roof, porous pavement, vegetative swale, ecological pond, and raingarden), and artificial rainwater. Design scenarios are categorized five type: 1)no GI, 2)conventional GI design(current design), 3)intensive GI design, 4)GI design+rainwater retarding reservoir 5)maximized rainwater retarding reservoir. Intensive GI design is to have attribute value to

  12. Error Analysis of Satellite Precipitation-Driven Modeling of Complex Terrain Flood Events

    NASA Astrophysics Data System (ADS)

    Mei, Y.; Nikolopoulos, E. I.; Anagnostou, E. N.; Zoccatelli, D.; Borga, M., Sr.

    2015-12-01

    The error characteristics of satellite precipitation driven flood event simulations over mountainous basins are evaluated in this study for eight different global satellite products. A methodology is devised to match the observed records of the flood events with the corresponding satellite and reference rainfall and runoff simulations. The flood events are sorted according to flood type (i.e. rain flood and flash flood) and basin's antecedent conditions represented by the event's runoff-to-precipitation ratio. The satellite precipitation products and runoff simulations are evaluated based on systematic and random error metrics applied on the matched event pairs and basin scale event properties (i.e. cumulative volume, timing and shape). Overall satellite-driven event runoff exhibits better error metrics than the satellite precipitation. Better error metrics are also shown for the rain flood events relative to the flash flood events. The event timing and shape from satellite-derived precipitation agreed well with the reference; the cumulative volume is mostly underestimated. In terms of error propagation, the study shows dampening effect in both systematic and random error components of the satellite-driven runoff time series relative to the satellite-retrieved event precipitation. This error dampening effect is less pronounced for the flash flood events and the rain flood events with high runoff coefficients. This study provides for a first time flood event characteristics of the satellite precipitation error propagation in flood modeling, which has implications on the Global Precipitation Measurement application in mountain flood hydrology.

  13. Molecular events during translocation and proofreading extracted from 200 static structures of DNA polymerase

    PubMed Central

    Ren, Zhong

    2016-01-01

    DNA polymerases in family B are workhorses of DNA replication that carry out the bulk of the job at a high speed with high accuracy. A polymerase in this family relies on a built-in exonuclease for proofreading. It has not been observed at the atomic resolution how the polymerase advances one nucleotide space on the DNA template strand after a correct nucleotide is incorporated, that is, a process known as translocation. It is even more puzzling how translocation is avoided after the primer strand is excised by the exonuclease and returned back to the polymerase active site once an error occurs. The structural events along the bifurcate pathways of translocation and proofreading have been unwittingly captured by hundreds of structures in Protein Data Bank. This study analyzes all available structures of a representative member in family B and reveals the orchestrated event sequence during translocation and proofreading. PMID:27325739

  14. Complexation thermodynamics of diglycolamide with f-elements: solvent extraction and density functional theory analysis.

    PubMed

    Ali, Sk M; Pahan, S; Bhattacharyya, A; Mohapatra, P K

    2016-04-14

    Comparative extraction of trivalent lanthanide and actinide ions (La(3+), Eu(3+), Lu(3+), Am(3+) and Cm(3+)) with tetra-n-octyl diglycolamide (TODGA) was studied and showed the trend: Lu(3+) > Eu(3+) > Cm(3+) > Am(3+) > La(3+). The structure, bonding, energetic and thermodynamic parameters of the trivalent lanthanide and actinide ions (La(3+), Eu(3+), Lu(3+), Am(3+) and Cm(3+)) with a tridentate ligand, tetra-methyl diglycolamide (TMDGA), are reported in the gas and solvent phases in order to understand their complexation and extraction behaviour. The calculations were performed using the generalized gradient approximated BP86 density functional and the hybrid B3LYP functional using SVP and TZVPP basis sets. The calculated structure obtained at the BP86/SVP level of optimization was found to be in close agreement with the X-ray data and also with the structure obtained at the B3LYP/TZVP level of theory. The free energy of extraction was found to be exergonic for the explicit monomer water model. From the solvent extraction experiment the order of extraction was observed as Lu(3+) > Eu(3+) > Cm(3+) > Am(3+) > La(3+), which was in line with the trends predicted based on the free energy changes in the gas phase calculations (ΔGgp). The Born-Haber thermodynamic cycle and the COSMO (conductor like screening model) solvation model were applied to calculate the free energy of extraction, ΔGext, of lanthanide and actinide ions in the aqueous-dodecane biphasic system and ΔGext, however, predicted different extraction trends. After dispersion correction (B3LYP-D3), the free energy of extraction for the metal ions was found to follow the order: Lu(3+) > Eu(3+) > La(3+), which was also observed in the solvent extraction experiments. Both COSMO and DCOSMO-RS models predict the same metal ion selectivity trend. Different bonding analyses indicate the electrostatic and less covalent nature of interactions between the ligands and the metal ions. PMID:27001244

  15. A novel feature extracting method of QRS complex classification for mobile ECG signals

    NASA Astrophysics Data System (ADS)

    Zhu, Lingyun; Wang, Dong; Huang, Xianying; Wang, Yue

    2007-12-01

    The conventional classification parameters of QRS complex suffer from larger activity rang of patients and lower signal to noise ratio in mobile cardiac telemonitoring system and can not meet the identification needs of ECG signal. Based on individual sinus heart rhythm template built with mobile ECG signals in time window, we present semblance index to extract the classification features of QRS complex precisely and expeditiously. Relative approximation r2 and absolute error r3 are used as estimating parameters of semblance between testing QRS complex and template. The evaluate parameters corresponding to QRS width and types are demonstrated to choose the proper index. The results show that 99.99 percent of the QRS complex for sinus and superventricular ECG signals can be distinguished through r2 but its average accurate ratio is only 46.16%. More than 97.84 percent of QRS complexes are identified using r3 but its accurate ratio to the sinus and superventricular is not better than r2. By the feature parameter of width, only 42.65 percent of QRS complexes are classified correctly, but its accurate ratio to the ventricular is superior to r2. To combine the respective superiority of three parameters, a nonlinear weighing computation of QRS width, r2 and r3 is introduced and the total classification accuracy up to 99.48% by combing indexes.

  16. Complex Parts, Complex Data: Why You Need to Understand What Radiation Single Event Testing Data Does and Doesn't Show and the Implications Thereof

    NASA Technical Reports Server (NTRS)

    LaBel, Kenneth A.; Berg, Melanie D.

    2015-01-01

    Electronic parts (integrated circuits) have grown in complexity such that determining all failure modes and risks from single particle event testing is impossible. In this presentation, the authors will present why this is so and provide some realism on what this means. Its all about understanding actual risks and not making assumptions.

  17. Complex Parts, Complex Data: Why You Need to Understand What Radiation Single Event Testing Data Does and Doesn't Show and the Implications Thereof

    NASA Technical Reports Server (NTRS)

    Label, Kenneth A.; Berg, Melanie D.

    2016-01-01

    Electronic parts (integrated circuits) have grown in complexity such that determining all failure modes and risks from single particle event testing is impossible. In this presentation, the authors will present why this is so and provide some realism on what this means. Its all about understanding actual risks and not making assumptions.

  18. Extraction of nickel from edible oils with a complexing agent prior to determination by FAAS.

    PubMed

    Tokay, Feyzullah; Bağdat, Sema

    2016-04-15

    In the present work, a new extraction method for separation of nickel from edible oils and determination by FAAS is reported. This method is based on extraction of Ni(II) ions from the oil to aqueous phase with N,N'-bis(4-methoxysalicylidene) ethylenediamine (MSE) and determination by FAAS. Properties of the complex formed between MSE and Ni(II) were investigated spectrophotometrically. Central composite design (CCD) was utilized for optimization of MSE to oil, stirring time and temperature, which were 0.97 mL g(-1), 15.4 min, and 29.7°C, respectively. The developed method was tested with an oil-based metal standard and the recovery was 93.8±3.9%. The proposed method was applied with five different edible oils. PMID:26616973

  19. World, We Have Problems: Simulation for Large Complex, Risky Projects, and Events

    NASA Technical Reports Server (NTRS)

    Elfrey, Priscilla

    2010-01-01

    Prior to a spacewalk during the NASA STS/129 mission in November 2009, Columbia Broadcasting System (CBS) correspondent William Harwood reported astronauts, "were awakened again", as they had been the day previously. Fearing something not properly connected was causing a leak, the crew, both on the ground and in space, stopped and checked everything. The alarm proved false. The crew did complete its work ahead of schedule, but the incident reminds us that correctly connecting hundreds and thousands of entities, subsystems and systems, finding leaks, loosening stuck valves, and adding replacements to very large complex systems over time does not occur magically. Everywhere major projects present similar pressures. Lives are at - risk. Responsibility is heavy. Large natural and human-created disasters introduce parallel difficulties as people work across boundaries their countries, disciplines, languages, and cultures with known immediate dangers as well as the unexpected. NASA has long accepted that when humans have to go where humans cannot go that simulation is the sole solution. The Agency uses simulation to achieve consensus, reduce ambiguity and uncertainty, understand problems, make decisions, support design, do planning and troubleshooting, as well as for operations, training, testing, and evaluation. Simulation is at the heart of all such complex systems, products, projects, programs, and events. Difficult, hazardous short and, especially, long-term activities have a persistent need for simulation from the first insight into a possibly workable idea or answer until the final report perhaps beyond our lifetime is put in the archive. With simulation we create a common mental model, try-out breakdowns of machinery or teamwork, and find opportunity for improvement. Lifecycle simulation proves to be increasingly important as risks and consequences intensify. Across the world, disasters are increasing. We anticipate more of them, as the results of global warming

  20. Modelling of a Zonda wind event in a complex terrain region using WRF

    NASA Astrophysics Data System (ADS)

    Fernandez, R. P.; Cremades, P. G.; Lakkis, G.; Allende, D. G.; Santos, R.; Puliafito, S. E.

    2012-04-01

    The air quality modeling in a regional scale requires the coupling to Numerical Weather Prediction (NWP) models, mainly when a high spatial and temporal resolution is required, such as in those cases related to large pollutants emissions episodes or extreme weather events. The Weather Research and Forecasting (WRF) is a last generation NWP model which computes temperature, pressure, humidity and wind fields in high spatial and temporal resolution. In order to perform simulations in complex terrain regions, WRF must be locally configured to obtain a proper representation of the physical processes, and an independent validation must be performed, both under common and extreme conditions. Once the local configuration is obtained, a full atmospheric chemistry modeling can be performed by means of WRF-Chem. In this work a mesoescale event of Zonda wind (similar to Foehn and Chinook winds) affecting the topographically complex mountainous region of Mendoza (Argentina) on February 15th, 2007 is represented using WRF. The model results are compared to the Argentine National Weather Service (SMN) observations at "El Plumerillo" station (WMO #87418), showing a good performance. A description of the local model configuration and most important physical parameterizations selected for the simulations is given, including the improvement of the default resolution of land use and land cover (LULC) fields. The high resolution modeling domain considered is centered at the city of Mendoza (32° 53' South, 68° 50' West), it extends 200 km N/S × 160 km E/W and includes a 3-nested domain downscaling of 36, 12 and 4 km resolution, respectively. The results for the Zonda wind episode show a very good performance of the model both in spatial and temporal scales. The temporal dew point variation (the physical variable that best describes the Zonda wind) shows a good agreement with the measured values, with a sharp decrease of 20 °C (from 16 °C to -4 °C) in 3 hours. A full 3-D regional

  1. Tracking vortices in superconductors: Extracting singularities from a discretized complex scalar field evolving in time

    NASA Astrophysics Data System (ADS)

    Phillips, Carolyn L.; Guo, Hanqi; Peterka, Tom; Karpeyev, Dmitry; Glatz, Andreas

    2016-02-01

    In type-II superconductors, the dynamics of magnetic flux vortices determine their transport properties. In the Ginzburg-Landau theory, vortices correspond to topological defects in the complex order parameter field. Earlier, in Phillips et al. [Phys. Rev. E 91, 023311 (2015), 10.1103/PhysRevE.91.023311], we introduced a method for extracting vortices from the discretized complex order parameter field generated by a large-scale simulation of vortex matter. With this method, at a fixed time step, each vortex [simplistically, a one-dimensional (1D) curve in 3D space] can be represented as a connected graph extracted from the discretized field. Here we extend this method as a function of time as well. A vortex now corresponds to a 2D space-time sheet embedded in 4D space time that can be represented as a connected graph extracted from the discretized field over both space and time. Vortices that interact by merging or splitting correspond to disappearance and appearance of holes in the connected graph in the time direction. This method of tracking vortices, which makes no assumptions about the scale or behavior of the vortices, can track the vortices with a resolution as good as the discretization of the temporally evolving complex scalar field. Additionally, even details of the trajectory between time steps can be reconstructed from the connected graph. With this form of vortex tracking, the details of vortex dynamics in a model of a superconducting materials can be understood in greater detail than previously possible.

  2. Offside Decisions by Expert Assistant Referees in Association Football: Perception and Recall of Spatial Positions in Complex Dynamic Events

    ERIC Educational Resources Information Center

    Gilis, Bart; Helsen, Werner; Catteeuw, Peter; Wagemans, Johan

    2008-01-01

    This study investigated the offside decision-making process in association football. The first aim was to capture the specific offside decision-making skills in complex dynamic events. Second, we analyzed the type of errors to investigate the factors leading to incorrect decisions. Federation Internationale de Football Association (FIFA; n = 29)…

  3. Modulation of flash-induced photosystem II fluorescence by events occurring at the water oxidizing complex.

    PubMed

    Putrenko, I I; Vasil'ev, S; Bruce, D

    1999-08-17

    The mechanism of flash-induced changes with a periodicity of four in photosystem II (PSII) fluorescence was investigated with the aim of further using fluorescence measurements as an approach to studying the structural and functional organization of the water-oxidizing complex (WOC). The decay of the flash-induced high fluorescence state of PSII was measured with pulse amplitude modulated fluorometry in thylakoids and PSII enriched membrane fragments. Calculated QA- decay was well described by three exponential decay components, reflecting QA- reoxidation with halftimes of 450 and 860 micros, 2 and 7.6 ms, and 111 and 135 ms in thylakoids and PSII membranes, respectively. The effect of modification of the PSII donor side by changing pH or by removal of the extrinsic 17 and 24 kDa proteins on period four oscillations in both maximum fluorescence yield and the relative contribution of QA- reoxidation reactions was compared to flash-induced oxygen yield. The four-step oxidation of the manganese cluster of the WOC was found to be necessary but not sufficient to produce modulation of PSII fluorescence. The capacity of the WOC to generate molecular oxygen was also required to observe a period four in the fluorescence; however, direct quenching by oxygen was not responsible for the modulation. Potential mechanisms responsible for the periodicity of four in both maximum fluorescence yield pattern and flash-dependent changes in proportion of centers with different QA- reoxidation rates are discussed with respect to intrinsic deprotonation events occurring at the WOC. PMID:10451357

  4. Modified diglycol-amides for actinide separation: solvent extraction and time-resolved laser fluorescence spectroscopy complexation studies

    SciTech Connect

    Wilden, A.; Modolo, G.; Lange, S.; Sadowski, F.; Bosbach, D.; Beele, B.B.; Panak, P.J.; Skerencak-Frech, A.; Geist, A.; Iqbal, M.; Verboom, W.

    2013-07-01

    In this work, the back-bone of the diglycolamide-structure of the TODGA extractant was modified by adding one or two methyl groups to the central methylene carbon-atoms. The influence of these structural modifications on the extraction behavior of trivalent actinides and lanthanides and other fission products was studied in solvent extraction experiments. The addition of methyl groups to the central methylene carbon atoms leads to reduced distribution ratios, also for Sr(II). This reduced extraction efficiency for Sr(II) is beneficial for process applications, as the co-extraction of Sr(II) can be avoided, resulting in an easier process design. The use of these modified diglycol-amides in solvent extraction processes is discussed. Furthermore, the complexation of Cm(III) and Eu(III) to the ligands was studied using Time-Resolved-Laser-Fluorescence-Spectroscopy (TRLFS). The complexes were characterized by slope analysis and conditional stability constants were determined.

  5. Extraction of an urease-active organo-complex from soil.

    NASA Technical Reports Server (NTRS)

    Burns, R. G.; El-Sayed, M. H.; Mclaren, A. D.

    1972-01-01

    Description of an extraction from a Dublin clay loam soil of a colloidal organic matter complex that is urease active and, by X-ray analysis, free of clays. Urease activity in the clay-free precipitates, as in the soil, was not destroyed by the activity of an added proteolytic enzyme, pronase. This is attributed to the circumstance that native soil urease resides in organic colloidal particles with pores large enough for water, urea, ammonia, and carbon dioxide to pass freely, but nevertheless small enough to exclude pronase.

  6. An Analysis Method for Superconducting Resonator Parameter Extraction with Complex Baseline Removal

    NASA Technical Reports Server (NTRS)

    Cataldo, Giuseppe

    2014-01-01

    A new semi-empirical model is proposed for extracting the quality (Q) factors of arrays of superconducting microwave kinetic inductance detectors (MKIDs). The determination of the total internal and coupling Q factors enables the computation of the loss in the superconducting transmission lines. The method used allows the simultaneous analysis of multiple interacting discrete resonators with the presence of a complex spectral baseline arising from reflections in the system. The baseline removal allows an unbiased estimate of the device response as measured in a cryogenic instrumentation setting.

  7. Deciphering landscape complexity to predict (non)linear responses to extreme climatic events

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extreme events are increasing in frequency and magnitude for many landscapes globally. Ecologically, most of the focus on extreme climatic events has been on effects of either short-term pulses (floods, freezes) or long-term drought. Multi-year increases in precipitation are also occurring with litt...

  8. An event generator for simulations of complex β-decay experiments

    NASA Astrophysics Data System (ADS)

    Jordan, D.; Algora, A.; Tain, J. L.

    2016-08-01

    This article describes a Monte Carlo event generator for the design, optimization and performance characterization of beta decay spectroscopy experimental set-ups. The event generator has been developed within the Geant4 simulation architecture and provides new features and greater flexibility in comparison with the current available decay generator.

  9. Large-scale immunopurification of ribonucleoprotein complexes from Drosophila nucleoplasmic extracts for tiling microarrays.

    PubMed

    Rio, Donald C

    2014-03-01

    It is of interest to be able to define sets of cellular RNAs associated with specific RNA-binding proteins. This "guilt by association" can lead to new insights into how RNA-binding proteins modulate posttranscriptional gene expression of specific target RNAs. To identify these RNAs, antibodies against RNA-binding proteins can be used to immunopurify endogenous RNA-protein complexes from cells, and then the associated RNAs can be characterized. The method described here was developed to identify binding regions on nuclear transcripts for Drosophila heterogeneous nuclear ribonucleoproteins (hnRNPs). An antibody is added to an RNP extract and incubated to allow antigen-antibody complexes to form. The antibody-antigen complexes are then retrieved by binding of the antibody constant region to staphylococcal Protein A immobilized on Sepharose beads. The bead-immobilized complexes are then washed and RNA is prepared. The RNA is used to generate random-primed cDNA, cRNA, and biotinlyated cDNA probes for use on Affymetrix whole-genome Drosophila tiling arrays. PMID:24591694

  10. Modified CTAB and TRIzol protocols improve RNA extraction from chemically complex Embryophyta1

    PubMed Central

    Jordon-Thaden, Ingrid E.; Chanderbali, Andre S.; Gitzendanner, Matthew A.; Soltis, Douglas E.

    2015-01-01

    Premise of the study: Here we present a series of protocols for RNA extraction across a diverse array of plants; we focus on woody, aromatic, aquatic, and other chemically complex taxa. Methods and Results: Ninety-one taxa were subjected to RNA extraction with three methods presented here: (1) TRIzol/TURBO DNA-free kits using the manufacturer’s protocol with the addition of sarkosyl; (2) a combination method using cetyltrimethylammonium bromide (CTAB) and TRIzol/sarkosyl/TURBO DNA-free; and (3) a combination of CTAB and QIAGEN RNeasy Plant Mini Kit. Bench-ready protocols are given. Conclusions: After an iterative process of working with chemically complex taxa, we conclude that the use of TRIzol supplemented with sarkosyl and the TURBO DNA-free kit is an effective, efficient, and robust method for obtaining RNA from 100 mg of leaf tissue of land plant species (Embryophyta) examined. Our protocols can be used to provide RNA of suitable stability, quantity, and quality for transcriptome sequencing. PMID:25995975

  11. Usefulness of Fragmented QRS Complex to Predict Arrhythmic Events and Cardiovascular Mortality in Patients With Noncompaction Cardiomyopathy.

    PubMed

    Cetin, Mehmet Serkan; Ozcan Cetin, Elif Hande; Canpolat, Ugur; Cay, Serkan; Topaloglu, Serkan; Temizhan, Ahmet; Aydogdu, Sinan

    2016-05-01

    We aimed to evaluate the prevalence and prognostic role of fragmented QRS complex (fQRS) in predicting arrhythmic events and cardiovascular mortality in patients with noncompaction cardiomyopathy (NCC). A total of 88 patients (64.8% men, mean age 38.6 ± 17.7 years) with the diagnosis of NCC were enrolled. Median follow-up time was 42.4 months. The fQRS was defined as the presence of ≥1 additional R wave (R') or notch on the R/S waves in ≥2 contiguous leads representing anterior (V1 to V5), inferior (II, III, and aVF), or lateral (I, aVL, and V6) myocardial segments. Compared to patients without fQRS group, patients with fQRS (fQRS (+) group) showed higher rates for total arrhythmic events, ventricular tachycardia, bradyarrhythmia requiring pacemaker, sudden cardiac death, cardiovascular mortality, and all-cause mortality. The cut-off point of ≥3 leads for the fQRS was the optimal point discriminating an arrhythmic event and cardiovascular mortality. In Kaplan-Meier survival analysis, total arrhythmic events and cardiovascular mortality occurred more frequently in the fQRS (+) group. In multivariate Cox proportional hazard regression analysis, after adjusting for other confounding factors, the presence of fQRS were found to be as an independent predictor of arrhythmic events (hazard ratio 3.850, 95% CI 1.062 to 9.947, p = 0.002) and cardiovascular mortality (hazard ratio 2.719, 95% CI 1.494 to 9.262, p = 0.005). In conclusion, the presence of fQRS complex, as a simple and feasible electrocardiographic marker, seems to be a novel predictor of arrhythmic events and cardiovascular mortality in patients with NCC. This simple parameter may be used in identifying patients at high risk for arrhythmic events and so individualization of specific therapies can be applied. PMID:26979479

  12. Studies on complexation and solvent extraction of lanthanides in the presence of diaza-18-crown-6-di-isopropionic acid.

    PubMed

    Kim, J S; Lee, C H; Han, S H; Suh, M Y

    1997-12-19

    Stability constants of some lanthanides with K22DAP (diaza-18-crown-6-diisopropionic acid) were determined by potentiometric titration method. The logarithmic values of these constants for La(III), Nd(III), Sm(III), Gd(III), Tb(III), Dy(III), Er(III), and Lu(III) are 11.14, 11.43, 11.78, 11.74, 11.95, 12.09, 11.49, and 10.88, respectively. Solvent extraction studies were carried out on the K22DAP complexes of La(III), Nd(III) and Lu(III) using TTA (thenoyltrifluoroacetone) as an extractant in different diluents. It appears that nitrobenzene, a diluent with high dielectric constant, favors the extraction of the complexes. Extraction rates of the K22DAP complexes of lanthanides were investigated at pH 5.5 and 8.0 with TTA in chloroform. The rates of extraction are found to be dependent upon the nature of the extracted species. Competitive extractions were carried out to see if selective extractions could be achieved. PMID:18967024

  13. Homologous Solar Events on 2011 January 27: Build-up and Propagation in a Complex Coronal Environment

    NASA Astrophysics Data System (ADS)

    Pick, M.; Stenborg, G.; Démoulin, P.; Zucca, P.; Lecacheux, A.

    2016-05-01

    In spite of the wealth of imaging observations at the extreme-ultraviolet (EUV), X-ray, and radio wavelengths, there are still relatively few cases where all of the imagery is available to study the full development of a coronal mass ejection (CME) event and its associated shock. The aim of this study is to contribute to the understanding of the role of the coronal environment in the development of CMEs and the formation of shocks, and their propagation. We have analyzed the interactions of a couple of homologous CME events with ambient coronal structures. Both events were launched in a direction far from the local vertical, and exhibited a radical change in their direction of propagation during their progression from the low corona into higher altitudes. Observations at EUV wavelengths from the Atmospheric Imaging Assembly instrument on board the Solar Dynamic Observatory were used to track the events in the low corona. The development of the events at higher altitudes was followed by the white-light coronagraphs on board the Solar and Heliospheric Observatory. Radio emissions produced during the development of the events were well recorded by the Nançay solar instruments. Thanks to their detection of accelerated electrons, the radio observations are an important complement to the EUV imaging. They allowed us to characterize the development of the associated shocks, and helped to unveil the physical processes behind the complex interactions between the CMEs and ambient medium (e.g., compression, reconnection).

  14. Ionic liquids as a key medium for efficient extraction of copper complexes from chia seeds (Salvia hispanica L.).

    PubMed

    Wojcieszek, Justyna; Popowski, Dominik; Ruzik, Lena

    2016-05-15

    Due to insufficient information, the aim of study was to concern on the optimization of extraction procedure of selected metal complexes with flavonoids from chia seeds. Evaluation of the amount of elements in compound, not only their total concentration content, is highly important due to the fact, that only a part from total content of metal is absorbed by human body. At the beginning the total amount of elements in chia seeds was established as 14.51±0.42 µg g(-1) for copper, 57.44±1.23 µg g(-1) for manganese, 81.12±1.89 µg g(-1) for zinc and 0.35±0.13 µg g(-1) for cobalt. After the most suitable solvent was established, effects of several parameters on the efficiency of metal extraction were studied. Solvent concentration, solid-solvent ratio, extraction method, extraction time and temperature have been investigated as independent variables. The optimal extraction conditions included vortexing during 20 min in 50°C, using an ionic liquid (1-butyl-3-methylimidazolium bromide) as an extractant, with solid-solvent ratio of 1:20. The determination of total and extractable amount of metals in chia seeds was carried out by standalone ICP MS. In addition, a complementary analysis of extracted metal complexes was performed using SEC-ICP MS method. It was confirmed that the ionic liquid is able to extract different copper complexes in comparison with commonly used solvents. The study indicated that extraction by using an ionic liquid has been successfully applied for determination of metals and metal complexes in chia seeds. PMID:26992545

  15. Detecting vortices in superconductors: extracting one-dimensional topological singularities from a discretized complex scalar field.

    PubMed

    Phillips, Carolyn L; Peterka, Tom; Karpeyev, Dmitry; Glatz, Andreas

    2015-02-01

    In type II superconductors, the dynamics of superconducting vortices determine their transport properties. In the Ginzburg-Landau theory, vortices correspond to topological defects in the complex order parameter. Extracting their precise positions and motion from discretized numerical simulation data is an important, but challenging, task. In the past, vortices have mostly been detected by analyzing the magnitude of the complex scalar field representing the order parameter and visualized by corresponding contour plots and isosurfaces. However, these methods, primarily used for small-scale simulations, blur the fine details of the vortices, scale poorly to large-scale simulations, and do not easily enable isolating and tracking individual vortices. Here we present a method for exactly finding the vortex core lines from a complex order parameter field. With this method, vortices can be easily described at a resolution even finer than the mesh itself. The precise determination of the vortex cores allows the interplay of the vortices inside a model superconductor to be visualized in higher resolution than has previously been possible. By representing the field as the set of vortices, this method also massively reduces the data footprint of the simulations and provides the data structures for further analysis and feature tracking. PMID:25768639

  16. Unfolding communities in large complex networks: Combining defensive and offensive label propagation for core extraction

    NASA Astrophysics Data System (ADS)

    Šubelj, Lovro; Bajec, Marko

    2011-03-01

    Label propagation has proven to be a fast method for detecting communities in large complex networks. Recent developments have also improved the accuracy of the approach; however, a general algorithm is still an open issue. We present an advanced label propagation algorithm that combines two unique strategies of community formation, namely, defensive preservation and offensive expansion of communities. The two strategies are combined in a hierarchical manner to recursively extract the core of the network and to identify whisker communities. The algorithm was evaluated on two classes of benchmark networks with planted partition and on 23 real-world networks ranging from networks with tens of nodes to networks with several tens of millions of edges. It is shown to be comparable to the current state-of-the-art community detection algorithms and superior to all previous label propagation algorithms, with comparable time complexity. In particular, analysis on real-world networks has proven that the algorithm has almost linear complexity, O(m1.19), and scales even better than the basic label propagation algorithm (m is the number of edges in the network).

  17. Complex effusive events at Kilauea as documented by the GOES satellite and remote video cameras

    USGS Publications Warehouse

    Harris, A.J.L.; Thornber, C.R.

    1999-01-01

    GOES provides thermal data for all of the Hawaiian volcanoes once every 15 min. We show how volcanic radiance time series produced from this data stream can be used as a simple measure of effusive activity. Two types of radiance trends in these time series can be used to monitor effusive activity: (a) Gradual variations in radiance reveal steady flow-field extension and tube development. (b) Discrete spikes correlate with short bursts of activity, such as lava fountaining or lava-lake overflows. We are confident that any effusive event covering more than 10,000 m2 of ground in less than 60 min will be unambiguously detectable using this approach. We demonstrate this capability using GOES, video camera and ground-based observational data for the current eruption of Kilauea volcano (Hawai'i). A GOES radiance time series was constructed from 3987 images between 19 June and 12 August 1997. This time series displayed 24 radiance spikes elevated more than two standard deviations above the mean; 19 of these are correlated with video-recorded short-burst effusive events. Less ambiguous events are interpreted, assessed and related to specific volcanic events by simultaneous use of permanently recording video camera data and ground-observer reports. The GOES radiance time series are automatically processed on data reception and made available in near-real-time, so such time series can contribute to three main monitoring functions: (a) automatically alerting major effusive events; (b) event confirmation and assessment; and (c) establishing effusive event chronology.

  18. Detection of Unusual Events and Trends in Complex Non-Stationary Data Streams

    SciTech Connect

    Perez, Rafael B; Protopopescu, Vladimir A; Worley, Brian Addison; Perez, Cristina

    2006-01-01

    The search for unusual events and trends hidden in multi-component, nonlinear, non-stationary, noisy signals is extremely important for a host of different applications, ranging from nuclear power plant and electric grid operation to internet traffic and implementation of non-proliferation protocols. In the context of this work, we define an unusual event as a local signal disturbance and a trend as a continuous carrier of information added to and different from the underlying baseline dynamics. The goal of this paper is to investigate the feasibility of detecting hidden intermittent events inside non-stationary signal data sets corrupted by high levels of noise, by using the Hilbert-Huang empirical mode decomposition method.

  19. Native Liquid Extraction Surface Analysis Mass Spectrometry: Analysis of Noncovalent Protein Complexes Directly from Dried Substrates

    NASA Astrophysics Data System (ADS)

    Martin, Nicholas J.; Griffiths, Rian L.; Edwards, Rebecca L.; Cooper, Helen J.

    2015-08-01

    Liquid extraction surface analysis (LESA) mass spectrometry is a promising tool for the analysis of intact proteins from biological substrates. Here, we demonstrate native LESA mass spectrometry of noncovalent protein complexes of myoglobin and hemoglobin from a range of surfaces. Holomyoglobin, in which apomyoglobin is noncovalently bound to the prosthetic heme group, was observed following LESA mass spectrometry of myoglobin dried onto glass and polyvinylidene fluoride surfaces. Tetrameric hemoglobin [(αβ)2 4H] was observed following LESA mass spectrometry of hemoglobin dried onto glass and polyvinylidene fluoride (PVDF) surfaces, and from dried blood spots (DBS) on filter paper. Heme-bound dimers and monomers were also observed. The `contact' LESA approach was particularly suitable for the analysis of hemoglobin tetramers from DBS.

  20. Extraction of conjugate main-stream structures from a complex network flow

    NASA Astrophysics Data System (ADS)

    Tamura, Koutarou; Takayasu, Hideki; Takayasu, Misako

    2015-04-01

    We introduce a method to extract main-stream structures for a given complex network flow by trimming less effective links. As the resulting main streams generally have an almost loopless treelike structure, we can define the stream basin size for each node, which characterizes the importance of the node with regard to the flow. As a real-world example, we apply this method to an interfirm trading network, both for the money flow and its conjugate—the material or service flow—confirming that both basin size distributions follow a similar power law that differs significantly from the basin size distributions of rivers in nature. We theoretically analyze the process of trimming and derive a consistent statistical formulation between the original link number and the basin size.

  1. Extraction of conjugate main-stream structures from a complex network flow.

    PubMed

    Tamura, Koutarou; Takayasu, Hideki; Takayasu, Misako

    2015-04-01

    We introduce a method to extract main-stream structures for a given complex network flow by trimming less effective links. As the resulting main streams generally have an almost loopless treelike structure, we can define the stream basin size for each node, which characterizes the importance of the node with regard to the flow. As a real-world example, we apply this method to an interfirm trading network, both for the money flow and its conjugate-the material or service flow-confirming that both basin size distributions follow a similar power law that differs significantly from the basin size distributions of rivers in nature. We theoretically analyze the process of trimming and derive a consistent statistical formulation between the original link number and the basin size. PMID:25974555

  2. Evaluation of expanded bed adsorption chromatography for extraction of prothrombin complex from Cohn Supernatant I.

    PubMed

    McCann, Karl B; Gomme, Peter T; Wu, John; Bertolini, Joseph

    2008-07-01

    This study evaluated the feasibility of substituting expanded bed adsorption (EBA) chromatography for an existing chromatographic purification process for the isolation of prothrombin complex concentrate (PCC) from Cohn Supernatant I. The EBA chromatography (Streamline) resins were compared to the current DEAE-cellulose resin for the extraction of PCC from Cohn SNI. EBA chromatography resins efficiently bound PCC from Cohn SNI at a significantly higher flow rate of up to 300 cm/h compared to 30 cm/h for the current DEAE-cellulose process. Composition and yield of the recovered PCC reflected the elution conditions used. The results indicate that EBA chromatography could be used to efficiently produce PCC comparable to existing products. PMID:18329287

  3. Knocking on wood: base metal complexes as catalysts for selective oxidation of lignin models and extracts.

    PubMed

    Hanson, Susan K; Baker, R Tom

    2015-07-21

    This work began as part of a biomass conversion catalysis project with UC Santa Barbara funded by the first NSF Chemical Bonding Center, CATSB. Recognizing that catalytic aerobic oxidation of diol C-C bonds could potentially be used to break down lignocellulose, we began to synthesize oxovanadium complexes and explore their fundamental reactivity. Of course there were theories regarding the oxidation mechanism, but our mechanistic studies soon revealed a number of surprises of the type that keep all chemists coming back to the bench! We realized that these reactions were also exciting in that they actually used the oxygen-on-every-carbon property of biomass-derived molecules to control the selectivity of the oxidation. When we found that these oxovanadium complexes tended to convert sugars predominantly to formic acid and carbon dioxide, we replaced one of the OH groups with an ether and entered the dark world of lignin chemistry. In this Account, we summarize results from our collaboration and from our individual labs. In particular, we show that oxidation selectivity (C-C vs C-O bond cleavage) of lignin models using air and vanadium complexes depends on the ancillary ligands, the reaction solvent, and the substrate structure (i.e., phenolic vs non-phenolic). Selected vanadium complexes in the presence of added base serve as effective alcohol oxidation catalysts via a novel base-assisted dehydrogenation pathway. In contrast, copper catalysts effect direct C-C bond cleavage of these lignin models, presumably through a radical pathway. The most active vanadium catalyst exhibits unique activity for the depolymerization of organosolv lignin. After Weckhuysen's excellent 2010 review on lignin valorization, the number of catalysis studies and approaches on both lignin models and extracts has expanded rapidly. Today we are seeing new start-ups and lignin production facilities sprouting up across the globe as we all work to prove wrong the old pulp and paper chemist

  4. Extractive Atmospheric Pressure Photoionization (EAPPI) Mass Spectrometry: Rapid Analysis of Chemicals in Complex Matrices

    NASA Astrophysics Data System (ADS)

    Liu, Chengyuan; Yang, Jiuzhong; Wang, Jian; Hu, Yonghua; Zhao, Wan; Zhou, Zhongyue; Qi, Fei; Pan, Yang

    2016-07-01

    Extractive atmospheric pressure photoionization (EAPPI) mass spectrometry was designed for rapid qualitative and quantitative analysis of chemicals in complex matrices. In this method, an ultrasonic nebulization system was applied to sample extraction, nebulization, and vaporization. Mixed with a gaseous dopant, vaporized analytes were ionized through ambient photon-induced ion-molecule reactions, and were mass-analyzed by a high resolution time-of-flight mass spectrometer (TOF-MS). After careful optimization and testing with pure sample solution, EAPPI was successfully applied to the fast screening of capsules, soil, natural products, and viscous compounds. Analysis was completed within a few seconds without the need for preseparation. Moreover, the quantification capability of EAPPI for matrices was evaluated by analyzing six polycyclic aromatic hydrocarbons (PAHs) in soil. The correlation coefficients (R 2 ) for standard curves of all six PAHs were above 0.99, and the detection limits were in the range of 0.16-0.34 ng/mg. In addition, EAPPI could also be used to monitor organic chemical reactions in real time.

  5. Neodymium(III) Complexes of Dialkylphosphoric and Dialkylphosphonic Acids Relevant to Liquid-Liquid Extraction Systems.

    PubMed

    Lumetta, Gregg J; Sinkov, Sergey I; Krause, Jeanette A; Sweet, Lucas E

    2016-02-15

    The complexes formed during the extraction of neodymium(III) into hydrophobic solvents containing acidic organophosphorus extractants were probed by single-crystal X-ray diffractometry, visible spectrophotometry, and Fourier-transform infrared spectroscopy. The crystal structure of the compound Nd(DMP)3 (1, DMP = dimethyl phosphate) revealed a polymeric arrangement in which each Nd(III) center is surrounded by six DMP oxygen atoms in a pseudo-octahedral environment. Adjacent Nd(III) ions are bridged by (MeO)2POO(-) anions, forming the polymeric network. The diffuse reflectance visible spectrum of 1 is nearly identical to that of the solid that is formed when an n-dodecane solution of di(2-ethylhexyl)phosphoric acid (HA) is saturated with Nd(III), indicating a similar coordination environment around the Nd center in the NdA3 solid. The visible spectrum of the HA solution fully loaded with Nd(III) is very similar to that of the NdA3 material, both displaying hypersensitive bands characteristic of an pseudo-octahedral coordination environment around Nd. These spectral characteristics persisted across a wide range of organic Nd concentrations, suggesting that the pseudo-octahedral coordination environment is maintained from dilute to saturated conditions. PMID:26815878

  6. A knowledge-based decision support system in bioinformatics: an application to protein complex extraction

    PubMed Central

    2013-01-01

    Background We introduce a Knowledge-based Decision Support System (KDSS) in order to face the Protein Complex Extraction issue. Using a Knowledge Base (KB) coding the expertise about the proposed scenario, our KDSS is able to suggest both strategies and tools, according to the features of input dataset. Our system provides a navigable workflow for the current experiment and furthermore it offers support in the configuration and running of every processing component of that workflow. This last feature makes our system a crossover between classical DSS and Workflow Management Systems. Results We briefly present the KDSS' architecture and basic concepts used in the design of the knowledge base and the reasoning component. The system is then tested using a subset of Saccharomyces cerevisiae Protein-Protein interaction dataset. We used this subset because it has been well studied in literature by several research groups in the field of complex extraction: in this way we could easily compare the results obtained through our KDSS with theirs. Our system suggests both a preprocessing and a clustering strategy, and for each of them it proposes and eventually runs suited algorithms. Our system's final results are then composed of a workflow of tasks, that can be reused for other experiments, and the specific numerical results for that particular trial. Conclusions The proposed approach, using the KDSS' knowledge base, provides a novel workflow that gives the best results with regard to the other workflows produced by the system. This workflow and its numeric results have been compared with other approaches about PPI network analysis found in literature, offering similar results. PMID:23368995

  7. Prediction of the most extreme rainfall events in the South American Andes: A statistical forecast based on complex networks

    NASA Astrophysics Data System (ADS)

    Boers, Niklas; Bookhagen, Bodo; Barbosa, Henrique; Marwan, Norbert; Kurths, Jürgen; Marengo, Jose

    2015-04-01

    During the monsoon season, the subtropical Andes in South America are exposed to spatially extensive extreme rainfall events that frequently lead to flashfloods and landslides with severe socio-economic impacts. Since dynamical weather forecast has substantial problems with predicting the most extreme events (above the 99th percentile), alternative forecast methods are called for. Based on complex network theory, we developed a general mathematical framework for statistical prediction of extreme events in significantly interrelated time series. The key idea of our approach is to make the internal synchronization structure of extreme events mathematically accessible in terms of the topology of a network which is constructed from measuring the synchronization of extreme events at different locations. The application of our method to high-spatiotemporal resolution rainfall data (TRMM 3B42) reveals a migration pattern of large convective systems from southeastern South America towards the Argentinean and Bolivian Andes, against the direction of the northwesterly low-level moisture flow from the Amazon Basin. Once these systems reach the Andes, they lead to spatially extensive extreme events up to elevations above 4000m, leading to substantial risks of associated natural hazards. Based on atmospheric composites, we could identify an intricate interplay of frontal systems approaching from the South, low-level moisture flow from the Amazon Basin to the North, and the Andean orography as responsible climatic mechanism. These insights allow to formulate a simple forecast rule predicting 60% (90% during El Niño conditions) of extreme rainfall events at the eastern slopes of the subtropical Andes. The rule can be computed from readily available rainfall and pressure data and is already being tested by local institutions for disaster preparation.

  8. Complexity extraction of electroencephalograms in Alzheimer's disease with weighted-permutation entropy

    NASA Astrophysics Data System (ADS)

    Deng, Bin; Liang, Li; Li, Shunan; Wang, Ruofan; Yu, Haitao; Wang, Jiang; Wei, Xile

    2015-04-01

    In this paper, weighted-permutation entropy (WPE) is applied to investigating the complexity abnormalities of Alzheimer's disease (AD) by analyzing 16-channel electroencephalograph (EEG) signals from 14 severe AD patients and 14 age-matched normal subjects. The WPE values are estimated in the delta, the theta, the alpha, and the beta sub-bands for each channel with an overlapped sliding window. WPE is modified from the permutation entropy (PE), which has been recently suggested as a measurement to extract the complexity of the EEG signals. The advantage of WPE over PE is verified by both the model simulated and the experimental EEG signals. Although the results show that both the average PE and WPE of AD patients are decreased in contrast with the normal group in these four sub-bands, especially in the theta band, WPE can exhibit a better performance in distinguishing the AD patients from the normal controls by the more significant differences in the four sub-bands, which may be attributed to the brain dysfunction. Thus, it suggests that WPE may become a probable useful tool to detect brain dysfunction in AD and it seems to be promising to disclose the abnormalities of brain activity for other neural disease.

  9. Cluster synchronization of complex networks via event-triggered strategy under stochastic sampling

    NASA Astrophysics Data System (ADS)

    Hu, Aihua; Cao, Jinde; Hu, Manfeng; Guo, Liuxiao

    2015-09-01

    This paper is concerned with the issue of mean square cluster synchronization of non-identical nodes connected by a directed network. Suppose that the nodes possess nonlinear dynamics and split into several clusters, then an event-triggered control scheme is proposed for synchronization based on the information from stochastic sampling. Meanwhile, an equilibrium is considered to be the synchronization state or the virtual leader for each cluster, which can apply pinning control to the following nodes. Assume that a spanning tree exists in the subgraph consisting of the nodes belonging to the same cluster and the corresponding virtual leader, and the instants for updating controllers are determined by the given event-triggered strategy, then some sufficient conditions for cluster synchronization are presented according to the Lyapunov stability theory and linear matrix inequality technique. Finally, a specific numerical example is shown to demonstrate the effectiveness of the theoretical results.

  10. Using rain-on-snow events to evaluate the quality of bias correction to represent complex inter-variable dependencies

    NASA Astrophysics Data System (ADS)

    Rössler, Ole; Bosshard, Thomas; Weingartner, Rolf

    2016-04-01

    A key issue for adaptation planning is the information of projections about changes of extremes. Climate projections of meteorological extremes and their downscaling are a challenge on their own. Yet - at least in hydrology - meteorological extremes are not necessarily hydrological extremes. These can also result from a sequence of days with only moderate meteorological conditions, too. This sequences are called "storylines". In climate change impact assess studies it is relevant to know, whether these meteorological storylines are represented in regional climate models, and how well can bias correction preserve or improve the representation. One storyline leading to hydrological extremes are rain-on-snow events, and more specifically rain-on-snowfall events. These events challenge the regional climate model and the bias correction in terms of representing absolute values and inter-variable dependences. This study makes use of the rain-on-snow-storylines to evaluate the performance of regional climate models and a bias correction method in reproducing complex inter-variable dependencies. At first, we applied a hydrological model to a mesoscale catchment in Switzerland that is known to be effected by rain-on-snow events. At second, the ERA-Interim driven regional climate model RCA4.5 - developed at SMHI - with a spatial resolution of 0.11 * 0.11 degree was used to drive the hydrological model. At third, bias-correction of the RCM was done applying the distribution based scaling (DBS) bias-correction method (Yang et al., 2010) developed at the SMHI. The bias-corrected data then also served as driving input data to the hydrological model. Based on the simulated runoff, as well as simulated precipitation, temperature, and snow pack data, an algorithm to detect rain-on-snow events was applied. Finally, the presence or absents of rain-on-snow events for the three different climate input data, ERA.RCA4.5, DBS corrected ERA.RC4 and observed climate, are evaluated within

  11. Determining the Total Volume of the 2.05 Ga Bushveld Magmatic Event: Correlation of the Molopo Farms Complex, Botswana

    NASA Astrophysics Data System (ADS)

    Escobar, E.; Gates, M.; Pitcavage, E.; Bybee, G. M.; Feineman, M. D.

    2015-12-01

    The Bushveld Igneous Complex (BIC) in South Africa, erupted 2.05 billion years ago, is the world's largest layered intrusion in the range of 710-1060 x 103 km3 conservatively. However, the total volume of the magmatic event that produced the BIC remains poorly known. Several other intrusions occurred approximately contemporaneously with the BIC, but a clear relationship between these multiple intrusions is yet to be determined. The Molopo Farms Complex (MFC) is a layered igneous complex of similar age 2.044 Ga ­± 24 Ma located in Botswana, 200km west of the far western limb of the BIC, with a total volume of 1300 km2. Using trace element analysis, this study makes an attempt to find a correlation between the magma that emplaced the Molopo Farms Complex with the Bushveld Igneous Complex. The MFC is related to the BIC and is located under approximately 200m of Kalahari sands, which prevents any direct sampling or observation. Unlike the BIC, the MFC is poorly studied creating a lack of information for the complex. Drill core samples from the MFC were analyzed to determine the trace element composition using an inductively coupled plasma mass spectrometer (ICP-MS). Using previously reported values for the BIC; a comparison can be made on both complexes to find possible correlations. The comparison of trace element schematics in the MFC and the BIC suggest that both complexes are derived from the same parental magma, often referred to as the "B1" magma. These comparisons allow for an assumption that the initial parental magma of the BIC may have also emplaced the MFC.

  12. METEOROLOGICAL EVENTS THAT PRODUCED THE HIGHEST GROUND-LEVEL CONCENTRATIONS DURING COMPLEX TERRAIN FIELD EXPERIMENTS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) is sponsoring the Complex Terrain Model Development project, a multi-year study to develop improved models for calculating ground-level air pollutant concentrations that result from large emission sources located in mountainous terra...

  13. Garlic revisited: antimicrobial activity of allicin-containing garlic extracts against Burkholderia cepacia complex.

    PubMed

    Wallock-Richards, Daynea; Doherty, Catherine J; Doherty, Lynsey; Clarke, David J; Place, Marc; Govan, John R W; Campopiano, Dominic J

    2014-01-01

    The antimicrobial activities of garlic and other plant alliums are primarily based on allicin, a thiosulphinate present in crushed garlic bulbs. We set out to determine if pure allicin and aqueous garlic extracts (AGE) exhibit antimicrobial properties against the Burkholderia cepacia complex (Bcc), the major bacterial phytopathogen for alliums and an intrinsically multiresistant and life-threatening human pathogen. We prepared an AGE from commercial garlic bulbs and used HPLC to quantify the amount of allicin therein using an aqueous allicin standard (AAS). Initially we determined the minimum inhibitory concentrations (MICs) of the AGE against 38 Bcc isolates; these MICs ranged from 0.5 to 3% (v/v). The antimicrobial activity of pure allicin (AAS) was confirmed by MIC and minimum bactericidal concentration (MBC) assays against a smaller panel of five Bcc isolates; these included three representative strains of the most clinically important species, B. cenocepacia. Time kill assays, in the presence of ten times MIC, showed that the bactericidal activity of AGE and AAS against B. cenocepacia C6433 correlated with the concentration of allicin. We also used protein mass spectrometry analysis to begin to investigate the possible molecular mechanisms of allicin with a recombinant form of a thiol-dependent peroxiredoxin (BCP, Prx) from B. cenocepacia. This revealed that AAS and AGE modifies an essential BCP catalytic cysteine residue and suggests a role for allicin as a general electrophilic reagent that targets protein thiols. To our knowledge, we report the first evidence that allicin and allicin-containing garlic extracts possess inhibitory and bactericidal activities against the Bcc. Present therapeutic options against these life-threatening pathogens are limited; thus, allicin-containing compounds merit investigation as adjuncts to existing antibiotics. PMID:25438250

  14. Cytotoxic and Nitric Oxide Inhibition Activities of Propolis Extract along with Microencapsulation by Complex Coacervation.

    PubMed

    Onbas, Rabia; Kazan, Aslihan; Nalbantsoy, Ayse; Yesil-Celiktas, Ozlem

    2016-09-01

    In this study, cytotoxicity of ethanol extract of propolis (EEP) originating from Sivas, Turkey was screened against several cancer cell lines, namely PC-3, U87MG, A-549, mPANC96, CaCo-2, MCF-7, HeLa, MDA-MB-231 and a non-tumor cell line HEK293 by MTT assay. The inhibition levels of inducible nitric oxide synthase (iNOS) were also determined by using RAW 264.7 macrophage cells following lipopolysaccharide (LPS) treatment. EEP exhibited significant cytotoxic nitric oxide inhibition activities with an IC50 value of 0.1 ± 0.1 μg/ml indicating a high potential as an anti-inflammatory agent. In spite of these promising results and the fact that propolis is a highly nutritive substance, its low solubility and bitter taste limit the applications as a natural supplement. Encapsulation might serve as a good strategy in order to overcome these problems. Complex coacervation was applied where the main focus was on surfactant type, polymer ratio (alginate:gelatin), stirring rate and concentration of core material. The mean particle size of unloaded microparticles were 22.62 μm obtained with gelatin:alginate ratio of 1:1 at a stirring rate of 1400 rpm with 2 ml of 1 % (w/v) sodium carboxymethyl cellulose (Na-CMC), whereas addition of EEP at a concentration of 100 mg/ml increased the mean particle size to 36.44 μm and yielded an encapsulation efficiency of 98.77 %. The cytotoxicities of EEP loaded microparticles were also assessed both on MCF-7 and MDA-MB-231 where similar results were achieved as free EEP which can enhance the possible use of propolis extract in the industry as a natural supplement. PMID:27380456

  15. Incorporating Love- and Rayleigh-wave magnitudes, unequal earthquake and explosion variance assumptions and interstation complexity for improved event screening

    SciTech Connect

    Anderson, Dale N; Bonner, Jessie L; Stroujkova, Anastasia; Shumway, Robert

    2009-01-01

    Our objective is to improve seismic event screening using the properties of surface waves, We are accomplishing this through (1) the development of a Love-wave magnitude formula that is complementary to the Russell (2006) formula for Rayleigh waves and (2) quantifying differences in complexities and magnitude variances for earthquake and explosion-generated surface waves. We have applied the M{sub s} (VMAX) analysis (Bonner et al., 2006) using both Love and Rayleigh waves to events in the Middle East and Korean Peninsula, For the Middle East dataset consisting of approximately 100 events, the Love M{sub s} (VMAX) is greater than the Rayleigh M{sub s} (VMAX) estimated for individual stations for the majority of the events and azimuths, with the exception of the measurements for the smaller events from European stations to the northeast. It is unclear whether these smaller events suffer from magnitude bias for the Love waves or whether the paths, which include the Caspian and Mediterranean, have variable attenuation for Love and Rayleigh waves. For the Korean Peninsula, we have estimated Rayleigh- and Love-wave magnitudes for 31 earthquakes and two nuclear explosions, including the 25 May 2009 event. For 25 of the earthquakes, the network-averaged Love-wave magnitude is larger than the Rayleigh-wave estimate. For the 2009 nuclear explosion, the Love-wave M{sub s} (VMAX) was 3.1 while the Rayleigh-wave magnitude was 3.6. We are also utilizing the potential of observed variances in M{sub s} estimates that differ significantly in earthquake and explosion populations. We have considered two possible methods for incorporating unequal variances into the discrimination problem and compared the performance of various approaches on a population of 73 western United States earthquakes and 131 Nevada Test Site explosions. The approach proposes replacing the M{sub s} component by M{sub s} + a* {sigma}, where {sigma} denotes the interstation standard deviation obtained from the

  16. Horizontal Gene Transfers from Bacteria to Entamoeba Complex: A Strategy for Dating Events along Species Divergence

    PubMed Central

    Romero, Miguel; Ximenez, Cecilia

    2016-01-01

    Horizontal gene transfer has proved to be relevant in eukaryotic evolution, as it has been found more often than expected and related to adaptation to certain niches. A relatively large list of laterally transferred genes has been proposed and evaluated for the parasite Entamoeba histolytica. The goals of this work were to elucidate the importance of lateral gene transfer along the evolutionary history of some members of the genus Entamoeba, through identifying donor groups and estimating the divergence time of some of these events. In order to estimate the divergence time of some of the horizontal gene transfer events, the dating of some Entamoeba species was necessary, following an indirect dating strategy based on the fossil record of plausible hosts. The divergence between E. histolytica and E. nuttallii probably occurred 5.93 million years ago (Mya); this lineage diverged from E. dispar 9.97 Mya, while the ancestor of the latter separated from E. invadens 68.18 Mya. We estimated times for 22 transferences; the most recent occurred 31.45 Mya and the oldest 253.59 Mya. Indeed, the acquisition of genes through lateral transfer may have triggered a period of adaptive radiation, thus playing a major role in the evolution of the Entamoeba genus. PMID:27239333

  17. Horizontal Gene Transfers from Bacteria to Entamoeba Complex: A Strategy for Dating Events along Species Divergence.

    PubMed

    Romero, Miguel; Cerritos, R; Ximenez, Cecilia

    2016-01-01

    Horizontal gene transfer has proved to be relevant in eukaryotic evolution, as it has been found more often than expected and related to adaptation to certain niches. A relatively large list of laterally transferred genes has been proposed and evaluated for the parasite Entamoeba histolytica. The goals of this work were to elucidate the importance of lateral gene transfer along the evolutionary history of some members of the genus Entamoeba, through identifying donor groups and estimating the divergence time of some of these events. In order to estimate the divergence time of some of the horizontal gene transfer events, the dating of some Entamoeba species was necessary, following an indirect dating strategy based on the fossil record of plausible hosts. The divergence between E. histolytica and E. nuttallii probably occurred 5.93 million years ago (Mya); this lineage diverged from E. dispar 9.97 Mya, while the ancestor of the latter separated from E. invadens 68.18 Mya. We estimated times for 22 transferences; the most recent occurred 31.45 Mya and the oldest 253.59 Mya. Indeed, the acquisition of genes through lateral transfer may have triggered a period of adaptive radiation, thus playing a major role in the evolution of the Entamoeba genus. PMID:27239333

  18. Heinrich events modeled with a coupled complex ice sheet-climate model

    NASA Astrophysics Data System (ADS)

    Ziemen, Florian; Rodehacke, Christian; Mikolajewicz Mikolajewicz, Uwe

    2013-04-01

    We investigate glacial climate variability with a coupled ice sheet model (ISM) - atmosphere-ocean-vegetation general circulation model (AOVGCM) system, focusing on one of the most prominent features of glacial climate variability, the Heinrich events. Modeling past climates and periods of past climate change is an important test of the capability of climate models to correctly represent future climate changes. Only if we can correctly represent past climates and climate changes, we can be confident about our predictions of future climate changes. We show results from two experiments: (1) a steady-state LGM experiment where the ice sheet model is accelerated by a factor of 10 compared to the climate model covering 30 kyrs in the ISM (3 kyrs in the AOVGCM) and (2) a synchronously coupled experiment focusing in on one ice sheet collapse covering 3.2 kyrs in both models. For the experiments, we coupled a modified version of the Parallel Ice Sheet Model (mPISM) bidirectionally with the AOVGCM ECHAM5/MPIOM/LPJ. ECHAM5 and LPJ were run in T31 resolution (~ 3.75°), MPIOM on a grid with a nominal resolution of 3° and poles over Greenland and Antarctica, mPISM on a 20 km grid covering most of the northern hemisphere. In the models, as well as in the coupling, no flux correction or anomaly maps are applied. The ice sheet surface mass balance is computed using a positive degree day scheme with lapse rate correction and height desertification effect. In the experiments, the surges of the Hudson Strait Ice Stream reach discharge rates of 60000 m3/s and show a typical recurrence interval of 7 kyrs, matching the basic characteristics for Heinrich events inferred from proxy data. The surges are consequences of an internal instability mechanism suggested by MacAyeal (1993) and various parts of the ice sheets show repeated surging. The large ice discharge during a surge of the Hudson Strait Ice Stream causes an expansion of the sea ice cover in the Labrador Sea and the adjacent

  19. Efficient Sample Preparation from Complex Biological Samples Using a Sliding Lid for Immobilized Droplet Extractions

    PubMed Central

    2015-01-01

    Sample preparation is a major bottleneck in many biological processes. Paramagnetic particles (PMPs) are a ubiquitous method for isolating analytes of interest from biological samples and are used for their ability to thoroughly sample a solution and be easily collected with a magnet. There are three main methods by which PMPs are used for sample preparation: (1) removal of fluid from the analyte-bound PMPs, (2) removal of analyte-bound PMPs from the solution, and (3) removal of the substrate (with immobilized analyte-bound PMPs). In this paper, we explore the third and least studied method for PMP-based sample preparation using a platform termed Sliding Lid for Immobilized Droplet Extractions (SLIDE). SLIDE leverages principles of surface tension and patterned hydrophobicity to create a simple-to-operate platform for sample isolation (cells, DNA, RNA, protein) and preparation (cell staining) without the need for time-intensive wash steps, use of immiscible fluids, or precise pinning geometries. Compared to other standard isolation protocols using PMPs, SLIDE is able to perform rapid sample preparation with low (0.6%) carryover of contaminants from the original sample. The natural recirculation occurring within the pinned droplets of SLIDE make possible the performance of multistep cell staining protocols within the SLIDE by simply resting the lid over the various sample droplets. SLIDE demonstrates a simple easy to use platform for sample preparation on a range of complex biological samples. PMID:24927449

  20. An europium(III) diglycolamide complex: insights into the coordination chemistry of lanthanides in solvent extraction.

    PubMed

    Antonio, Mark R; McAlister, Daniel R; Horwitz, E Philip

    2015-01-14

    The synthesis, stoichiometry, and structural characterization of a homoleptic, cationic europium(III) complex with three neutral tetraalkyldiglycolamide ligands are reported. The tri(bismuth tetrachloride)tris(N,N,N',N'-tetra-n-octyldiglycolamide)Eu salt, [Eu(TODGA)3][(BiCl4)3] obtained from methanol was examined by Eu L3-edge X-ray absorption spectroscopy (XAS) to reveal an inner-sphere coordination of Eu(3+) that arises from 9 O atoms and two next-nearest coordination spheres that arise from 6 carbon atoms each. A structural model is proposed in which each TODGA ligand with its O=Ca-Cb-O-Cb-Ca=O backbone acts as a tridentate O donor, where the two carbonyl O atoms and the one ether O atom bond to Eu(3+). Given the structural rigidity of the tridentate coordination motif in [Eu(TODGA)3](3+) with six 5-membered chelate rings, the six Eu-Ca and six Eu-Cb interactions are readily resolved in the EXAFS (extended X-ray absorption fine structure) spectrum. The three charge balancing [BiCl4](-) anions are beyond the cationic [Eu(TODGA)3](3+) cluster in an outer sphere environment that is too distant to be detected by XAS. Despite their sizeable length and propensity for entanglement, the four n-octyl groups of each TODGA (for a total of twelve) do not perturb the Eu(3+) coordination environment over that seen from previously reported single-crystal structures of tripositive lanthanide (Ln(3+)) complexes with tetraalkyldiglycolamide ligands (of the same 1:3 metal-to-ligand ratio stoichiometry) but having shorter i-propyl and i-butyl groups. The present results set the foundation for understanding advanced solvent extraction processes for the separation of the minor, tripositive actinides (Am, Cm) from the Ln(3+) ions in terms of the local structure of Eu(3+) in a solid state coordination complex with TODGA. PMID:25310364

  1. Early Oligocene geomagnetic field behavior from ODP Site 1128: Complex records of short-period polarity events

    NASA Astrophysics Data System (ADS)

    Molina-Garza, R. S.; Fuller, M. D.

    2001-12-01

    At Site 1128, in the Great Australian Bight, Leg 182 of the Ocean Drilling Program recovered a thick (~350 m) section of Upper Eocene and Lower Oligocene marine calcareous clays. Shipboard measurements established a magnetostratigraphy that can unambiguously be correlated to chrons C13n to C10n of the global polarity time scale (GPTS), and a less complete record of chrons C17n to C15r (due to poor core recovery). Correlation to the GPTS is further supported by available biostratigraphic data. For the Lower Oligocene sequence, average sedimentation rate is estimated at ~4 cm/kyr. The sediments recovered thus allow to test for the completeness and reliability of the geomagnetic field polarity during the Early Oligocene. The original shipboard long-core measurements suggested the presence of additional short polarity events or geomagnetic field excursions during chrons C13n, C12r, C11r, and C11n. In order to examine the reliability of the record and the nature of possible short-polarity events, we obtained discrete samples from the entire sequence at ~1 m intervals, with a closer sample spacing in critical intervals (~10 cm). The natural remanence of these sediments is normally simple. After removing a small soft overprint, the magnetization decays towards the origin with distributed coercivities and distributed unblocking temperatures. Demagnetization behavior and other rock magnetic data indicate that the remanence resides primarily in a cubic phase such as magnetite or maghemite, with a small contribution from hematite. Discrete samples from chron C12r did not reproduce the long-core record for two of the supposed events, single samples suggest the presence of short events or cryptochrons near the base of both C13n and C12r, and multiple samples suggest the existence of short-period normal polarity events during C11r and near the top of C12r. The records of these events are, however, complex. Demagnetization results indicate that the magnetization consists of an

  2. Medicinal herb extract and a single-compound drug confer similar complex pharmacogenomic activities in mcf-7 cells.

    PubMed

    Yang, Ning-Sun; Shyur, Lie-Fen; Chen, Chih-Huai; Wang, Sheng-Yang; Tzeng, Chi-Meng

    2004-01-01

    Metabolite profiling and DNA microarray analysis of global gene expression profiles were employed to characterize the bioactivities of the herbal extract of Anoectochilus formosanus (AF), a popular folk medicine with anticancer activity, in MCF-7 cancer cells. The pharmacogenomic activities of this plant extract as a crude phytocompound mixture were compared to those conferred by the single-compound drug, plumbagin. A similar level of complexity in transcriptional regulation at the genomic level was observed for both AF extract- and plumbagin-treated MCF-7 cells, as revealed by the number of up- or downregulated genes as well as by the specific but distinct patterns found in the gene-clustering analysis. This finding offers evidence to support the search for fractionated medicinal herb extracts or phytocompound mixtures, in addition to single-compound drugs, as defined therapeutic agents. PMID:15067226

  3. Bézier curve string method for the study of rare events in complex chemical systems

    NASA Astrophysics Data System (ADS)

    Bellucci, Michael A.; Trout, Bernhardt L.

    2014-08-01

    We present a new string method for finding the most probable transition pathway and optimal reaction coordinate in complex chemical systems. Our approach evolves an analytic parametric curve, known as a Bézier curve, to the most probable transition path between metastable regions in configuration space. In addition, we demonstrate that the geometric properties of the Bézier curve can be used to construct the optimal reaction coordinate near the most probable reaction path, and can further be used to devise a ranking vector capable of identifying precisely which collective variables are most important for governing the transition between metastable states. We discuss the algorithmic details of the Bézier curve string method, analyze its stability, accuracy and efficiency, and illustrate its capabilities using model potential energy functions. In particular, we use the degree elevation property of Bézier curves to develop an algorithm that adaptively learns the degree polynomial necessary to accurately represent the most probable transition path. Subsequently, we apply our method to the isomerization of alanine dipeptide, and demonstrate that the reaction coordinate obtained from the Bézier curve string method is in excellent agreement with the optimal reaction coordinate constructed from an aimless shooting and maximum likelihood procedure. Finally, we apply our method to a large complex system and study the homogenous nucleation of benzene from the melt. In these two examples, we illustrate that the ranking vector correctly identifies which collective variables govern these chemical transitions.

  4. Extraction of the fluoride-, chloride-, and bromide complexes of the elements Nb, Ta, Pa, and 105 into aliphatic amines

    NASA Astrophysics Data System (ADS)

    Paulus, W.; Kratz, J. V.; Strub, E.; Zauner, S.; Brüchle, W.; Pershina, V.; Schädel, M.; Schausten, B.; Adams, J. L.; Gregorich, K. E.; Hoffman, D. C.; Laue, C.; Lee, D. M.; McGrath, C. A.; Shaughnessy, D. K.; Strellis, D. A.; Sylwester, E. R.

    1999-01-01

    Previous studies of the halide complex formation of element 105 in HCl/HF mixtures and extractions into triisooctyl amine (TIOA) had been performed with the Automated Rapid Chemistry Apparatus, ARCA II. Element 105 was shown to be sorbed on the column from 12 M HCl/0.02 M HF together with its lighter homologues Nb, Ta and the pseudohomologue Pa. In elutions with 10 M HCl/0.025 M HF, 4 M HCl/0.02 M HF, and 0.5 M HCl/0.01 M HF, the extraction sequence Ta>Nb>105>Pa was observed and element 105 behaved very differently from its closest homologue Ta. As it is not possible within reasonable effort to model the many presumably mixed fluoride-chloride complexes involved in these studies, theoretical calculations were performed in the pure chloride system predicting a reversed sequence of extraction. To verify this experimentally, and in order to perform a systematic study of halide complexation of the group 5 elements, new batch extraction experiments for Nb, Ta, and Pa were performed with the quaternary ammonium salt Aliquat 336 in pure HF, HCl, and HBr solutions. Based on these results, new chromatographic column separations were elaborated to study separately the fluoride and chloride complexation of element 105 with ARCA II. In the system Aliquat 336/HF, after feeding of the activity onto the column in 0.5 M HF, element 105 did not elute in 4 M HF (Pa fraction) but showed a higher distribution coefficient close to that of Nb (and Ta). In the system Aliquat 336/HCl, after feeding onto the column in 10 M HCl, element 105 showed a distribution coefficient in 6 M HCl close to that of Nb establishing an extraction sequence Pa>Nb≥105>Ta which is theoretically predicted by considering the competition between hydrolysis and complex formation.

  5. Probing energy transfer events in the light harvesting complex 2 (LH2) of Rhodobacter sphaeroides with two-dimensional spectroscopy

    SciTech Connect

    Fidler, Andrew F.; Singh, Ved P.; Engel, Gregory S.; Long, Phillip D.; Dahlberg, Peter D.

    2013-10-21

    Excitation energy transfer events in the photosynthetic light harvesting complex 2 (LH2) of Rhodobacter sphaeroides are investigated with polarization controlled two-dimensional electronic spectroscopy. A spectrally broadened pulse allows simultaneous measurement of the energy transfer within and between the two absorption bands at 800 nm and 850 nm. The phased all-parallel polarization two-dimensional spectra resolve the initial events of energy transfer by separating the intra-band and inter-band relaxation processes across the two-dimensional map. The internal dynamics of the 800 nm region of the spectra are resolved as a cross peak that grows in on an ultrafast time scale, reflecting energy transfer between higher lying excitations of the B850 chromophores into the B800 states. We utilize a polarization sequence designed to highlight the initial excited state dynamics which uncovers an ultrafast transfer component between the two bands that was not observed in the all-parallel polarization data. We attribute the ultrafast transfer component to energy transfer from higher energy exciton states to lower energy states of the strongly coupled B850 chromophores. Connecting the spectroscopic signature to the molecular structure, we reveal multiple relaxation pathways including a cyclic transfer of energy between the two rings of the complex.

  6. TP53 mutations are early events in chronic lymphocytic leukemia disease progression and precede evolution to complex karyotypes.

    PubMed

    Lazarian, Gregory; Tausch, Eugen; Eclache, Virginie; Sebaa, Amel; Bianchi, Vincent; Letestu, Remi; Collon, Jean-Francois; Lefebvre, Valerie; Gardano, Laura; Varin-Blank, Nadine; Soussi, Thierry; Stilgenbauer, Stephen; Cymbalista, Florence; Baran-Marszak, Fanny

    2016-10-15

    TP53 abnormalities lead to resistance to purine analogues and are found in over 40% of patients with refractory chronic lymphocytic leukemia (CLL). At diagnosis, no more than 5% of patients carry the 17p deletion, most cases harbour mutations within the other TP53 allele. The incidence of a TP53 mutation as the only alteration is approximately 5%, but this depends on the sensitivity of the technique. Recently, having a complex karyotype has been considered a strong adverse prognostic factor. However, there are no longitudinal studies simultaneously examining the presence of the 17p deletion, TP53 mutations and karyotype abnormalities. We conducted a retrospective longitudinal study of 31 relapsed/refractory CLL patients. Two to six blood samples per patient were analyzed, with a median follow-up of 8 years. In this report, we assessed the sequence of events of TP53 clonal evolution and correlated the presence of TP53 abnormalities to genetic instability during progression and treatment. Next-generation sequencing allowed the early detection of TP53 mutated clones and was able to be performed on a routine basis, demonstrating an excellent correlation between the Illumina and Ion Torrent technologies. We concluded that TP53 mutations are early events and precede clonal evolution to complex karyotypes. We strongly recommend the early and iterated detection of TP53 mutations in progressive cases. PMID:27270786

  7. Probing energy transfer events in the light harvesting complex 2 (LH2) of Rhodobacter sphaeroides with two-dimensional spectroscopy

    PubMed Central

    Fidler, Andrew F.; Singh, Ved P.; Long, Phillip D.; Dahlberg, Peter D.; Engel, Gregory S.

    2013-01-01

    Excitation energy transfer events in the photosynthetic light harvesting complex 2 (LH2) of Rhodobacter sphaeroides are investigated with polarization controlled two-dimensional electronic spectroscopy. A spectrally broadened pulse allows simultaneous measurement of the energy transfer within and between the two absorption bands at 800 nm and 850 nm. The phased all-parallel polarization two-dimensional spectra resolve the initial events of energy transfer by separating the intra-band and inter-band relaxation processes across the two-dimensional map. The internal dynamics of the 800 nm region of the spectra are resolved as a cross peak that grows in on an ultrafast time scale, reflecting energy transfer between higher lying excitations of the B850 chromophores into the B800 states. We utilize a polarization sequence designed to highlight the initial excited state dynamics which uncovers an ultrafast transfer component between the two bands that was not observed in the all-parallel polarization data. We attribute the ultrafast transfer component to energy transfer from higher energy exciton states to lower energy states of the strongly coupled B850 chromophores. Connecting the spectroscopic signature to the molecular structure, we reveal multiple relaxation pathways including a cyclic transfer of energy between the two rings of the complex. PMID:24160544

  8. Complex Socio-Ecological Dynamics driven by extreme events in the Amazon

    NASA Astrophysics Data System (ADS)

    Pinho, P. F.

    2015-12-01

    Several years with extreme floods or droughts in the past decade have caused human suffering in remote communities of the Brazilian Amazon. Despite documented local knowledge and practices for coping with the high seasonal variability characteristic of the region's hydrology (e.g. 10m change in river levels between dry and flood seasons), and despite 'civil Defense' interventions by various levels of government, the more extreme years seem to have exceeded the coping capacity of the community. In this paper, we explore whether there is a real increase in variability, whether the community perceives that recent extreme events are outside the experience which shapes their responses to 'normal' levels of variability, and what science-based policy could contribute to greater local resilience. Hydrological analyses suggest that variability is indeed increasing, in line with expectations from future climate change. However, current measures of hydrological regimes do not predict years with social hardship very well. Interviewees in two regions are able to express their strategies for dealing with 'normal' variability very well, but also identify ways in which abnormal years exceed their ability to cope. Current Civil Defense arrangements struggle to deliver emergency assistance in a sufficiently timely and locally appropriate fashion. Combining these insights in the context of social-ecological change, we suggest how better integration of science, policy and local knowledge could improve resilience to future trends, and identify some contributions science could make into such an arrangement.

  9. The event-related brain potential as an index of attention allocation in complex displays

    NASA Technical Reports Server (NTRS)

    Wickens, C. D.; Heffley, E. F.; Kramer, A. F.; Donchin, E.

    1980-01-01

    The advantages of employing the event-related brain potential (ERP) in the assessment of allocation of attention in dynamic environments are discussed. Three experiments are presented in which the P300 component of the ERP is demonstrated to be a useful index of subjects' locus of attention. The first two experiments were concerned with the allocation of attention during discrete and continuous visual monitoring tasks. The results indicated that a P300 was elicited only by stimuli to which the subject had to attend in order to perform successfully the task. The third experiment was conducted to assess the sensitivity of P300 to the manner in which attention is allocated to different aspects of a display during the performance of a 3-dimensional target acquisition task. The amplitude of the P300 was found to reflect differences between two levels of workload, as well as the task relevance of the stimuli. The results of the experiments are discussed in terms of their utility in the evaluation of the design of man-machine systems as well as in the study of the allocation of attention in operational environments.

  10. Improvement of photon extraction efficiency of GaN-based LED using micro and nano complex polymer structures

    NASA Astrophysics Data System (ADS)

    Cho, Joong-Yeon; Byeon, Kyeong-Jae; Park, Hyoungwon; Kim, Jinseung; Kim, Hyeong-Seok; Lee, Heon

    2011-10-01

    A micro- and nanoscale complex structure made of a high refractive index polymer ( n = 2.08) was formed on the ITO electrode layer of an edge-emitting type GaN blue light-emitting diode (LED), in order to improve the photon extraction efficiency by suppressing total internal reflection of photons. The nanoimprint lithography process was used to form the micro- and nanoscale complex structures, using a polymer resin with dispersed TiO2 nano-particles as an imprint resin. Plasma processing, such as reactive ion etching, was used to form the micro- and nano-scale complex structure; thus, plasma-induced damage to the LED device can be avoided. Due to the high refractive index polymeric micro- and nanostructure on the ITO layer, the electroluminescence emission was increased up to 20%, compared to an identical LED that was grown on a patterned sapphire substrate to improve photon extraction efficiency.

  11. An evaluation of the PENCURV model for penetration events in complex targets.

    SciTech Connect

    Broyles, Todd P.

    2004-07-01

    Three complex target penetration scenarios are run with a model developed by the U. S. Army Engineer Waterways Experiment Station, called PENCURV. The results are compared with both test data and a Zapotec model to evaluate PENCURV's suitability for conducting broad-based scoping studies on a variety of targets to give first order solutions to the problem of G-loading. Under many circumstances, the simpler, empirically based PENCURV model compares well with test data and the much more sophisticated Zapotec model. The results suggest that, if PENCURV were enhanced to include rotational acceleration in its G-loading computations, it would provide much more accurate solutions for a wide variety of penetration problems. Data from an improved PENCURV program would allow for faster, lower cost optimization of targets, test parameters and penetration bodies as Sandia National Laboratories continues in its evaluation of the survivability requirements for earth penetrating sensors and weapons.

  12. The Development of Narrative Productivity, Syntactic Complexity, Referential Cohesion and Event Content in Four- to Eight-Year-Old Finnish Children

    ERIC Educational Resources Information Center

    Mäkinen, Leena; Loukusa, Soile; Nieminen, Lea; Leinonen, Eeva; Kunnari, Sari

    2014-01-01

    This study focuses on the development of narrative structure and the relationship between narrative productivity and event content. A total of 172 Finnish children aged between four and eight participated. Their picture-elicited narrations were analysed for productivity, syntactic complexity, referential cohesion and event content. Each measure…

  13. Ultrastructural midgut events in Culicidae larvae fed with Bacillus sphaericus 2297 spore/crystal complex.

    PubMed

    Charles, J F

    1987-01-01

    Ingestion of Bacillus sphaericus 2297 spore/crystal complex by Culicidae larvae Anopheles stephensi, Culex pipiens subsp. pipiens and Aedes aegypti was rapidly followed by a dissolution of the protein crystalline inclusions inside the anterior stomach of the three species. During the first day of intoxication, B. sphaericus spores germinated within the midgut lumen, and were in a vegetative stage between 36-48 h after ingestion when the larvae began to die. Ultrastructural observations focused on larval midgut showed alterations which differed according to the mosquito species, being localized mainly in the gastric caeca and posterior stomach. With the bacterial concentration used, neither general cell swelling nor complete breakdown of the midgut epithelium was recorded before larval death. In A. stephensi larval midgut epithelium large low-electron-density areas appeared, rough endoplasmic reticula formed numerous concentrical structures and mitochondria swelled. Large vacuoles (of unknown origin) appeared early on in the C. pipiens midgut cells, and rough endoplasmic reticula broke into small vesicles. Midgut epithelial cells of A. aegypti showed mitochondria swelling except in the anterior stomach, and a vacuolisation of smooth reticula: these aspects remained unchanged until the larvae died. PMID:3663390

  14. Complex source mechanisms of mining-induced seismic events - implications for surface effects

    NASA Astrophysics Data System (ADS)

    Orlecka-Sikora, B.; Cesca, S.; Lasocki, S.; Rudzinski, L.; Lizurek, L.; Wiejacz, P.; Urban, P.; kozlowska, M.

    2012-04-01

    The seismicity of Legnica-Głogów Copper District (LGCD) is induced by mining activities in three mines: Lubin, Rudna and Polkowice-Sieroszowice. Ground motion caused by strong tremors might affect local infrastructure. "Żelazny Most" tailings pond, the biggest structure of this type in Europe, is here under special concern. Due to surface objects protection, Rudna Mine has been running ground motion monitoring for several years. From June 2010 to June 2011 unusually strong and extensive surface impact has been observed for 6 mining tremors induced in one of Rudna mining sections. The observed peak ground acceleration (PGA) for both horizontal and vertical component were in or even beyond 99% confidence interval for prediction. The aim of this paper is analyze the reason of such unusual ground motion. On the basis of registrations from Rudna Mine mining seismological network and records from Polish Seismological Network held by the Institute of Geophysics Polish Academy of Sciences (IGF PAN), the source mechanisms of these 6 tremors were calculated using a time domain moment tensor inversion. Furthermore, a kinematic analysis of the seismic source was performed, in order to determine the rupture planes orientations and rupture directions. These results showed that in case of the investigated tremors, point source models and shear fault mechanisms, which are most often assumed in mining seismology, are invalid. All analyzed events indicate extended sources with non-shear mechanism. The rapture planes have small dip angles and the rupture starts at the tremors hypocenter and propagates in the direction opposite to the plane dip. The tensional component plays here also big role. These source mechanisms well explain such observed strong ground motion, and calculated synthetic PGA values well correlates with observed ones. The relationship between mining tremors were also under investigation. All subsequent tremors occurred in the area of increased stress due to

  15. The extraction and determination of thiocyanate complexes by use of polyurethane foam.

    PubMed

    Chow, A; Ginsberg, S L

    1983-08-01

    Metal thiocyanate solutions were extracted with polyether-type polyurethane foam and the metal contents determined by X-ray fluorescence. Iron, cobalt and zinc were extracted individually and collectively from 3.0M NH(4)Cl and 1.0M NH(4)SCN solutions. Similarly platinum and palladium could be simultaneously extracted from 0.12MNH(4)SCN and 5.0MNH(4)Cl for subsequent determination. The metal extractions were more than 95% complete and the determination of one metal was not affected by the presence of the others. PMID:18963433

  16. Extractive spectrophotometry of the molybdenum (III) 1,10-phenanthroline thiocyanate and 2,2'-bipyridyl thiocyanate complexes.

    PubMed

    Bhadra, A K; Banerjee, S

    1973-03-01

    New extraction spectrophotometric methods for the determination of small amounts of molybdenum have been developed, using thiocyanate and 1,10-phenanthroline or 2,2'-bipyridyl as reagents in the presence of chlorostannous acid. Extracts of the ternary complexes of tervalent molybdenum in 1,2-dichloroethane obey Beer's law in the range 1-10 mug/ml at 525 nm. A 10-fold excess of iron and vanadium and 100-fold excess of tungsten, phosphorus and silicate do not interfere. PMID:18961283

  17. Summary report of results of the vapor vacuum extraction test at the RWMC (Radioactive Waste Management Complex)

    SciTech Connect

    Sisson, J.B.; Ellis, G.C.

    1990-11-01

    A test scale vapor vacuum extraction system was operated for four months at the Radioactive Waste Management Complex. The extraction system removed more than 65 million ft{sup 3} of soil gas containing 429 Kg of Carbon Tetrachloride and 164 Kg of TCE. Hydraulic properties of the basalts were estimated and input into a numerical transport model. The model simulations indicated that a rubble zone at 190 ft dominated the soil gas flow pattern. Refined calibration of transport models will allow enhancement of the production system design to increase operational efficiency and effectiveness. 7 refs., 18 figs.

  18. Complex Sedimentary and Tectonic Events Captured in Stable Sulfur Isotope Profiles from the IODP Expedition 344

    NASA Astrophysics Data System (ADS)

    Gott, C.; Riedinger, N.; Torres, M. E.; Solomon, E. A.; Bates, S. M.; Lyons, T. W.

    2014-12-01

    The impact of dynamic sedimentary and tectonic systems on biogeochemical processes, particularly the sulfur cycle, is poorly understood. To better elucidate these relationships, analyses were conducted on sediments collected during Integrated Ocean Drilling Project (IODP) Expedition 344. A primary goal of the CRISP (Costa Rica Seismogenesis Project) expedition is to explore diagenetic processes, e.g. fluid flow; relating to the complex sedimentary and tectonic environments along the Costa Rica margin. Samples collected from sites U1381C, U1413B, and U1414A record non-steady state conditions in both the solid phase and the pore water profiles, although it is most pronounced in the latter. The penetration depth of pore water sulfate at these sites varies strongly with depth between 100, 15 and several hundreds of meters, respectively. The corresponding hydrogen sulfide concentrations are >400 μM at Holes U1381C, and U1413B while they are <4 μM at Hole U1414A. The measured concentrations of iron sulfides in the sediments indicate that pyrite is the main sulfur-bearing mineral, with concentrations of 2-3 wt. % at sites U1413B and U1414A. Recorded in the sulfur isotope signal is the likely origin of the heterogeneity between sites. At Site U1414, the 34S isotopically enriched sulfate (δ34S>+60 ‰) is reflected in the δ34S profile of the in situ iron sulfides. We interpret these data as being indicative of fluid flow, potentially along fracture zones, seeps and/or pockmark features seen elsewhere in this region.

  19. Complexity of Arsenic Biogeochemistry in Surface Water Systems as Influenced by a Hydrologic Event

    NASA Astrophysics Data System (ADS)

    Markley, C. T.; Herbert, B. E.

    2006-12-01

    The arsenic cycle in oxic, surface water environments is often controlled by oxy-hydroxide minerals through sorption/desorption and precipitation/dissolution reactions. However, there are numerous instances where these minerals are found in low concentrations and/or are minimally reactive with respect to aqueous arsenic species. The presence of other anions may competitively inhibit arsenic sorption to oxy-hydroxide surfaces, thus increasing the bioavailability of arsenic and the potential toxic impacts. Microbe-mediated reactions can further impact arsenic fate and transport through accumulation and biotransformation. Arsenic biotransformation via reduction and/or methylation may result in an increased proportion of thermodynamically unfavorable arsenic species such as arsenite and methylated arsenicals in oxic surface waters. The reduced arsenic species, arsenite, is considered more mobile and toxic than the oxic species, arsenate while methylated arsenicals are often considered less toxic species. The complexity of these biogeochemical characteristics highlights the importance of studying arsenic in surface water environments. Particulate and aqueous phase metals (Fe, Mn, Al) and anions (As, P, S) were measured in surface water samples collected from the outflow creek of an arsenic-contaminated lake at high and low flow rates. Arsenic speciation, quantified via HPLC-ICP-MS, was dominated by methylated arsenicals at concentrations up to 82.7 μg/l. The common oxide-forming elements, Fe, Mn and Al were measured via ICP-AES at concentrations up to 2.4 mg/l, 0.88 mg/l and 3.3 mg/l, respectively. However, arsenic was not associated with the particulate phase mineralogy, being approximately 100% in the aqueous (< 0.2 μm ) phase, indicating high arsenic bioavailability. High alkalinity, phosphorous and sulfur concentrations up to 516 mgHCO3/meq, 2.0mg/l and 50 mg/l, respectively, likely out-competed arsenic for sorption to these oxide mineral surfaces. Geochemical

  20. Phosphoprotein extraction from the dentine/cementum complex of human tooth roots.

    PubMed

    McCurdy, S P; Clarkson, B H; Speirs, R L; Feagin, F F

    1990-01-01

    Root shards were placed in dialysis tubing and demineralized to completion in either 10% disodium EDTA, pH 7.4, 0.6 M HCl, 0.1 M HCl, 0.5 M acetic or 75 mM-25 mM lactic-acetic acids. The demineralized shards were then re-extracted with 0.05 M tris-HCl, 1.0 M NaCl. DEAE chromatography revealed that the major peak of the 0.6 M CHl and EDTA extracts contained organic phosphorus, whereas much less organic phosphorus was found in the major peak of the 0.1 M HCl extract. Analysis of the re-extracts gave a pattern opposite to that obtained from the initial extractions. Measurements of protein and organic phosphorus released during extraction and re-extraction confirmed these results. Staining of SDS-PAGE gels for phosphoprotein with Stains-All resulted in a blue smear in fractions containing organic phosphorus. Thus the extraction of phosphoproteins from human tooth roots differed depending upon the demineralizing conditions. This ability to remove phosphoprotein differentially will allow further investigation of the role of phosphoprotein in mineralization and remineralization. PMID:2115325

  1. Monitoring extracted beams of the nuclotron accelerator complex for "energy + transmutation" experiments

    NASA Astrophysics Data System (ADS)

    Baldin, A. A.; Berlev, A. I.; Vasil'ev, S. E.; Vishnevskiy, A. V.; Vladimirova, N. M.; Kudashkin, I. V.; Makan'kin, A. M.; Paraipan, M.; Tyutyunnikov, S. I.

    2016-03-01

    A monitoring system for measuring absolute intensity and the space—time structure of extracted beams of Nuclotron based on ionization and activation methods has been created and tested. The monitoring system provides a measurement of the absolute intensity of extracted beams with a precision of 10% and beam position with a precision of 0.5 mm.

  2. Very High Resolution Numerical Weather Prediction of Wind Shear Event in the Complex Terrain Around Juneau Alaska

    NASA Astrophysics Data System (ADS)

    Morton, D.; Arnold, D.; Schicker, I.; Dierking, C.; Harrison, K.

    2011-12-01

    Juneau International Airport is surrounded by complex terrain, often presenting challenging conditions to departing aircraft. General aviation departure procedures for Runway 08 include a 180-degree right turn "as soon as practical" in order to avoid steeply rising terrain. Under strong wind conditions characterized by post-frontal topographically enhanced wind shear, aircraft following these procedures may encounter turbulence or wind shear classified as severe. In January 1993, a Boeing 727 aircraft at a 30-degree bank encountered extreme crosswinds resulting in departure from controlled flight, with successful recovery occurring within only 50 meters of the ground. In this work, we focus on a similar event at Juneau from December 2009. This case has been modeled with WRF at very high resolutions down to 111 m horizontal, with mixed results. The focus of this work is to investigate in more detail the problems, costs and benefits of using very high resolution topography and model runs in a high-wind event in complex terrain. Several model runs will be performed, and results will be compared with each other and station observations available through the Juneau Airport Wind System (JAWS). Two high resolution topographies - the USGS National Elevation Dataset (NED) and the Shuttle Radar Topography Mission (SRTM) - will be compared with the USGS 30s topography in their ability to match the real topography and their influence on forecast winds. Additionally, an attempt will be made to push the model into the realm of Large Eddy Simulation (LES) with a 50 m horizontal resolution in a limited region.

  3. Purification of plant complex protein extracts in non-denaturing conditions by in-solution isoelectric focusing.

    PubMed

    Ferreira, R A; Martins-Dias, S

    2016-09-15

    An alternative approach for plant complex protein extracts pre-purification by in-solution isoelectric focusing in non-denaturing conditions is presented. The separation of biologically active proteins, in narrow ranges of isoelectric point (pI) was obtained by a modified OFFGEL electrophoresis. Two different water-soluble protein extracts from Phragmites leaves were fractionated into 24 fractions within a 3-10 pI range at 10 °C in the absence of denaturing/reducing agents. One-dimensional electrophoretic analysis revealed different protein distribution patterns and the effective fractionation of both protein extracts. Peroxidase activity of each fraction confirmed that proteins remained active and pre-purification occurred. Biological triplicates assured the needed reproducibility. PMID:27396497

  4. Characterisation of sub-micron particle number concentrations and formation events in the western Bushveld Igeneous Complex, South Africa

    NASA Astrophysics Data System (ADS)

    Hirsikko, A.; Vakkari, V.; Tiitta, P.; Manninen, H. E.; Gagné, S.; Laakso, H.; Kulmala, M.; Mirme, A.; Mirme, S.; Mabaso, D.; Beukes, J. P.; Laakso, L.

    2012-01-01

    South Africa holds significant mineral resources, with a substantial fraction of these reserves occurring in a large geological structure termed the Bushveld Igeneous Complex (BIC). The majority of the world's platinum group metals (PGMs) and chromium originate from the BIC. Considering the importance of PGMs in the manufacturing of automotive catalytic converters, as well as the relatively poor current state of air quality and the general lack of atmospheric research in the BIC, atmospheric related research in this geographical area is of local (South African) and of international interest. The western limb of the BIC is the most exploited, with at least eleven pyrometallurgical smelters occurring within a 55 km radius. Due to the lure of employment in the industrialised BIC, the area is populated by informal, semi-formal and formal residential developments. In order to investigate the characteristics and processes affecting sub-micron particle number concentrations and formation events, air ion and aerosol particle size distribution and concentration measurements were conducted for over two years at Marikana in the heart of the western BIC. Our results indicated that high amounts of Aitken and accumulation mode particles originated from domestic burning for heating and cooking in the morning and evening, while during daytime SO2-based nucleation (from industrial emissions) was the most probable source for large number concentrations of nucleation and Aitken mode particles. Nucleation event day frequency was extremely high, i.e. 86% of the analysed days, which to the knowledge of the authors is the highest frequency ever reported. Secondary particle formation was influenced both by local pollution sources and regional ambient conditions. Therefore, our observation of the annual cycle and magnitude of the particle formation and growth rates during nucleation events were similar to the results from a semi-clean savannah site in South Africa.

  5. Characterisation of sub-micron particle number concentrations and formation events in the western Bushveld Igneous Complex, South Africa

    NASA Astrophysics Data System (ADS)

    Hirsikko, A.; Vakkari, V.; Tiitta, P.; Manninen, H. E.; Gagné, S.; Laakso, H.; Kulmala, M.; Mirme, A.; Mirme, S.; Mabaso, D.; Beukes, J. P.; Laakso, L.

    2012-05-01

    South Africa holds significant mineral resources, with a substantial fraction of these reserves occurring and being processed in a large geological structure termed the Bushveld Igneous Complex (BIC). The area is also highly populated by informal, semi-formal and formal residential developments. However, knowledge of air quality and research related to the atmosphere is still very limited in the area. In order to investigate the characteristics and processes affecting sub-micron particle number concentrations and formation events, air ion and aerosol particle size distributions and number concentrations, together with meteorological parameters, trace gases and particulate matter (PM) were measured for over two years at Marikana in the heart of the western BIC. The observations showed that trace gas (i.e. SO2, NOx, CO) and black carbon concentrations were relatively high, but in general within the limits of local air quality standards. The area was characterised by very high condensation sink due to background aerosol particles, PM10 and O3 concentration. The results indicated that high amounts of Aitken and accumulation mode particles originated from domestic burning for heating and cooking in the morning and evening, while during daytime SO2-based nucleation followed by the growth by condensation of vapours from industrial, residential and natural sources was the most probable source for large number concentrations of nucleation and Aitken mode particles. Nucleation event day frequency was extremely high, i.e. 86% of the analysed days, which to the knowledge of the authors is the highest frequency ever reported. The air mass back trajectory and wind direction analyses showed that the secondary particle formation was influenced both by local and regional pollution and vapour sources. Therefore, our observation of the annual cycle and magnitude of the particle formation and growth rates during nucleation events were similar to results previously published for a semi

  6. Extraction, Thermodynamic Analysis, and Precipitation Mechanism of MnS-TiN Complex Inclusions in Low-Sulfur Steels

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Zhang, Lifeng; Duan, Haojian; Zhang, Ying; Luo, Yan; Conejo, Alberto N.

    2016-06-01

    Inclusions in square billets of low-sulfur steels employed in the production of steel springs were fully extracted using an improved non-aqueous solution electrolytic method and were characterized as oxides, MnS, and TiN-MnS complex inclusions. Inclusions were analyzed using SEM for their three-dimensional morphology. The formation mechanism of the complex TiN-MnS was investigated analyzing the equilibrium precipitation conditions during cooling from the liquid through solidification and in the solid state. In this analysis, three microsegregation models were employed. It was found that titanium nitride precipitates first and then manganese sulfide. Electron backscattered diffraction is employed to explore the crystal orientation relationship between TiN and MnS in the complex inclusions, which provided additional elements to fully describe the mechanism of formation of the observed TiN-MnS complex inclusions.

  7. Complex network analysis of high rainfall events during the northeast monsoon over south peninsular India and Sri Lanka

    NASA Astrophysics Data System (ADS)

    Martin, P.; Malik, N.; Marwan, N.; Kurths, J.

    2012-04-01

    The Indian Summer monsoon (ISM) accounts for a large part of the annual rainfall budget across most of the Indian peninsula; however, the coastal regions along the southeast Indian peninsula, as well as Sri Lanka, receive 50% or more of their annual rainfall budget during the northeast monsoon (NEM), or winter monsoon, during the months from October through December. In this study, we investigate the behavior of the NEM over the last 60 years using complex network theory. The network is constructed according to a method previously developed for the ISM, using event synchronization of extreme rainfall events as a correlation measure to create directed and undirected links between geographical locations, which represent potential pathways of moisture transport. Network measures, such as degree centrality and closeness centrality, are then used to illuminate the dynamics of the NEM rainfall over the relevant regions, and to examine the spatial distribution and temporal evolution of the rainfall. Understanding the circulation of the monsoon cycle as a whole, i.e. the NEM together with the ISM, is vital for the agricultural industry and thus the population of the affected areas.

  8. Evaluation of DNA extraction techniques for detecting Mycobacterium tuberculosis complex organisms in Asian elephant trunk wash samples.

    PubMed

    Kay, Meagan K; Linke, Lyndsey; Triantis, Joni; Salman, M D; Larsen, R Scott

    2011-02-01

    Rapid and sensitive diagnostic assays for the detection of tuberculous mycobacteria in elephants are lacking. DNA extraction with PCR analysis is useful for tuberculosis screening in many species but has not been validated on elephant trunk wash samples. We estimated the analytical sensitivity and specificity of three DNA extraction methods to detect Mycobacterium tuberculosis complex organisms in trunk wash specimens. A ZR soil microbe DNA kit (ZR) and a traditional salt and ethanol precipitation (TSEP) approach were evaluated under three different treatment conditions: heat treatment, phenol treatment, and contamination with Mycobacterium avium. A third approach, using a column filtration method, was evaluated for samples contaminated with soil. Trunk wash samples from uninfected elephants were spiked with various concentrations of M. bovis cells and subjected to the described treatment conditions prior to DNA extraction. Extracted DNA was amplified using IS6110-targeted PCR analysis. The ZR and TSEP methods detected as low as 1 to 5 M. bovis cells and 10 M. bovis cells, respectively, per 1.5 ml of trunk wash under all three conditions. Depending on the amount of soil present, the column filtration method detected as low as 5 to 50 M. bovis cells per 1.5 ml of trunk wash. Analytical specificity was assessed by DNA extraction from species of nontuberculous mycobacteria and amplification using the same PCR technique. Only M. bovis DNA was amplified, indicating 100% analytical specificity of this PCR technique. Our results indicate that these DNA extraction techniques offer promise as useful tests for detection of M. tuberculosis complex organisms in elephant trunk wash specimens. PMID:21159933

  9. Synthesis, characterization and extraction studies of some metal (II) complexes containing (hydrazoneoxime and bis-acylhydrazone) moieties.

    PubMed

    Al-Ne'aimi, Mohammed Mahmmod; Al-Khuder, Mohammed Moudar

    2013-03-15

    In this study, diacetylmonoximebenzoylhydrazone (L(1)H(2)) and 1,4-diacetylbenzene bis(benzoyl hydrazone) (L(2)H(2)) were synthesized by the condensation of benzohydrazide with diacetyl monoxime and 1,4-diacetylbenzene, respectively. Complexes of these ligands with Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) inos were prepared with a metal:ligand ratio of 1:2 for L(1)H(2) ligand, and 1:1 for L(2)H(2) ligand. The ligands and their complexes were elucidated on the basis of elemental analyses CHN, AAS, FT-IR, (1)H- and (13)C NMR spectra, UV-vis spectra and magnetic susceptibility measurements. Results show the L(1)H(2) ligand act as monoanionic O,N,N-tridentate and coordination takes place in the enol form through the oxime nitrogen, the imine nitrogen and the enolate oxygen atoms with a N(4)O(2) donor environment, while the L(2)H(2) ligand act as a dianionic O,N,N,O-tetradentate and coordination takes place in the enol form through the enolate oxygen and the azomethine nitrogen atoms with a N(2)O(2) donor environment. These results are consistent with the formation of mononuclear metal (II) complexes [M(L(1)H)(2)], and binuclear polymeric metal (II) complexes [{M(2)(L(2))}(n)]. The extraction ability of both ligands were examined in chloroform by the liquid-liquid extraction of selected transition metal [Co(2+), Ni(2+), Cu(2+), Zn(2+) and Pb(2+)] cations. The effects of pH and contact time on the percentage extraction of metal (II) ions were studied under the optimum extraction conditions. The (L(1)H(2)) ligand shows strong binding ability toward copper(II) and lead(II) ions, while the (L(2)H(2)) ligand shows strong binding ability toward nickel(II) and zinc(II) ions. PMID:23333690

  10. Synthesis, characterization and extraction studies of some metal (II) complexes containing (hydrazoneoxime and bis-acylhydrazone) moieties

    NASA Astrophysics Data System (ADS)

    Al-Ne'aimi, Mohammed Mahmmod; Al-Khuder, Mohammed Moudar

    2013-03-01

    In this study, diacetylmonoximebenzoylhydrazone (L1H2) and 1,4-diacetylbenzene bis(benzoyl hydrazone) (L2H2) were synthesized by the condensation of benzohydrazide with diacetyl monoxime and 1,4-diacetylbenzene, respectively. Complexes of these ligands with Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) inos were prepared with a metal:ligand ratio of 1:2 for L1H2 ligand, and 1:1 for L2H2 ligand. The ligands and their complexes were elucidated on the basis of elemental analyses CHN, AAS, FT-IR, 1H- and 13C NMR spectra, UV-vis spectra and magnetic susceptibility measurements. Results show the L1H2 ligand act as monoanionic O,N,N-tridentate and coordination takes place in the enol form through the oxime nitrogen, the imine nitrogen and the enolate oxygen atoms with a N4O2 donor environment, while the L2H2 ligand act as a dianionic O,N,N,O-tetradentate and coordination takes place in the enol form through the enolate oxygen and the azomethine nitrogen atoms with a N2O2 donor environment. These results are consistent with the formation of mononuclear metal (II) complexes [M(L1H)2], and binuclear polymeric metal (II) complexes [{M2(L2)}n]. The extraction ability of both ligands were examined in chloroform by the liquid-liquid extraction of selected transition metal [Co2+, Ni2+, Cu2+, Zn2+ and Pb2+] cations. The effects of pH and contact time on the percentage extraction of metal (II) ions were studied under the optimum extraction conditions. The (L1H2) ligand shows strong binding ability toward copper(II) and lead(II) ions, while the (L2H2) ligand shows strong binding ability toward nickel(II) and zinc(II) ions.

  11. Evolutionary site-number changes of ribosomal DNA loci during speciation: complex scenarios of ancestral and more recent polyploid events

    PubMed Central

    Rosato, Marcela; Moreno-Saiz, Juan C.; Galián, José A.; Rosselló, Josep A.

    2015-01-01

    Several genome duplications have been identified in the evolution of seed plants, providing unique systems for studying karyological processes promoting diversification and speciation. Knowledge about the number of ribosomal DNA (rDNA) loci, together with their chromosomal distribution and structure, provides clues about organismal and molecular evolution at various phylogenetic levels. In this work, we aim to elucidate the evolutionary dynamics of karyological and rDNA site-number variation in all known taxa of subtribe Vellinae, showing a complex scenario of ancestral and more recent polyploid events. Specifically, we aim to infer the ancestral chromosome numbers and patterns of chromosome number variation, assess patterns of variation of both 45S and 5S rDNA families, trends in site-number change of rDNA loci within homoploid and polyploid series, and reconstruct the evolutionary history of rDNA site number using a phylogenetic hypothesis as a framework. The best-fitting model of chromosome number evolution with a high likelihood score suggests that the Vellinae core showing x = 17 chromosomes arose by duplication events from a recent x = 8 ancestor. Our survey suggests more complex patterns of polyploid evolution than previously noted for Vellinae. High polyploidization events (6x, 8x) arose independently in the basal clade Vella castrilensis–V. lucentina, where extant diploid species are unknown. Reconstruction of ancestral rDNA states in Vellinae supports the inference that the ancestral number of loci in the subtribe was two for each multigene family, suggesting that an overall tendency towards a net loss of 5S rDNA loci occurred during the splitting of Vellinae ancestors from the remaining Brassiceae lineages. A contrasting pattern for rDNA site change in both paleopolyploid and neopolyploid species was linked to diversification of Vellinae lineages. This suggests dynamic and independent changes in rDNA site number during speciation processes and a

  12. Assessing the Influence of an Individual Event in Complex Fault Spreading Network Based on Dynamic Uncertain Causality Graph.

    PubMed

    Dong, Chunling; Zhao, Yue; Zhang, Qin

    2016-08-01

    Identifying the pivotal causes and highly influential spreaders in fault propagation processes is crucial for improving the maintenance decision making for complex systems under abnormal and emergency situations. A dynamic uncertain causality graph-based method is introduced in this paper to explicitly model the uncertain causalities among system components, identify fault conditions, locate the fault origins, and predict the spreading tendency by means of probabilistic reasoning. A new algorithm is proposed to assess the impacts of an individual event by investigating the corresponding node's time-variant betweenness centrality and the strength of global causal influence in the fault propagation network. The algorithm does not depend on the whole original and static network but on the real-time spreading behaviors and dynamics, which makes the algorithm to be specifically targeted and more efficient. Experiments on both simulated networks and real-world systems demonstrate the accuracy, effectiveness, and comprehensibility of the proposed method for the fault management of power grids and other complex networked systems. PMID:27101619

  13. Electric field-assisted solid phase extraction and cleanup of ionic compounds in complex food matrices: Fluoroquinolones in eggs.

    PubMed

    Ribeiro, Cyntia Cabral; Orlando, Ricardo Mathias; Rohwedder, Jarbas José Rodrigues; Reyes, Felix Guillermo Reyes; Rath, Susanne

    2016-05-15

    The use of electric fields as additional driving forces in sample preparation techniques is an innovative approach that is environmentally friendly, straightforward, and able to overcome several limitations of conventional sample preparation procedures. In this work, the advantages of electric field-assisted solid phase extraction (E-SPE) using syringe-type cartridges were demonstrated for the extraction of four fluoroquinolones (FQs) in their anionic forms. The FQs were extracted from eggs and subsequently determined by UHPLC-MS/MS. The use of electric fields during the washing and final elution steps resulted in a significant improvement of the extraction efficiencies for almost all FQs when compared to conventional SPE. Intra- and inter-day assays showed coefficients of variation below 10%. The better cleanup also resulted in the appearance of less precipitated matter in the final eluate, as well as reduced matrix effects. The results showed that the electrophoretic forces derived from electric fields are a promising way of significantly increasing the extraction efficiency of ionic analytes, while minimizing matrix effects associated with complex samples. PMID:26992547

  14. New chelating reagents for preconcentration, separation, determination of metal complexes by high performance liquid chromatography and solid phase extraction

    SciTech Connect

    Qian, Yan wen.

    1991-12-03

    A general scheme is outlined for rapid determination of metal cations by complexation and subsequent HPLC separation. The synthesis and general properties are described for several new thiohydrazone chelating reagents. Solubility considerations suggest that the metal complexes have a positive charge. Excellent chromatographic separations are obtained for mixtures of up to seven metal complexes. Addition of a positively charged additive to the eluent is shown to have a significant effect on both the retention times and sharpness of the chromatographic peaks. Separation of the metal complexes on resins with a permanent charge is also shown to be feasible. Two new hydrazone reagents have been synthesized and characterized. Trace metal ions in aqueous solution are complexed by one of the hydrazones and the resulting metal complexes are solid phase extracted onto a mini cation-exchange or polymeric column. The uptake of metal complexes is complete and the elution step is fast and complete. The quantitative recoveries of metal ions determined by both spectrophotometric method and ICP-MS are very satisfactory and agree with each other.

  15. Insulin-sensitizing and beneficial lipid-metabolic effects of the water-soluble melanin complex extracted from Inonotus obliquus.

    PubMed

    Lee, Jung-Han; Hyun, Chang-Kee

    2014-09-01

    Inonotus obliquus has been traditionally used for treatment of metabolic diseases; however, the mechanism remains to be elucidated. In this study, we found that the water-soluble melanin complex extracted from I. obliquus improved insulin sensitivity and reduced adiposity in high fat (HF)-fed obese mice. When the melanin complex was treated to 3T3-L1 adipocytes, insulin-stimulated glucose uptake was increased significantly, and its phosphoinositide 3-kinase-dependent action was proven with wortmannin treatment. Additionally, dose-dependent increases in Akt phosphorylation and glucose transporter 4 translocation into the plasma membrane were observed in melanin complex-treated cells. Adiponectin gene expression in 3T3-L1 cells incubated with melanin complex increased which was corroborated by increased AMP-activated protein kinase phosphorylation in HepG2 and C2C12 cells treated with conditioned media from the 3T3-L1 culture. Melanin complex-treated 3T3-L1 cells showed no significant change in expression of several lipogenic genes, whereas enhanced expressions of fatty acid oxidative genes were observed. Similarly, the epididymal adipose tissue of melanin complex-treated HF-fed mice had higher expression of fatty acid oxidative genes without significant change in lipogenic gene expression. Together, these results suggest that the water-soluble melanin complex of I. obliquus exerts antihyperglycemic and beneficial lipid-metabolic effects, making it a candidate for promising antidiabetic agent. PMID:24615848

  16. Developing a complex independent component analysis technique to extract non-stationary patterns from geophysical time-series

    NASA Astrophysics Data System (ADS)

    Forootan, Ehsan; Kusche, Jürgen

    2016-04-01

    Geodetic/geophysical observations, such as the time series of global terrestrial water storage change or sea level and temperature change, represent samples of physical processes and therefore contain information about complex physical interactionswith many inherent time scales. Extracting relevant information from these samples, for example quantifying the seasonality of a physical process or its variability due to large-scale ocean-atmosphere interactions, is not possible by rendering simple time series approaches. In the last decades, decomposition techniques have found increasing interest for extracting patterns from geophysical observations. Traditionally, principal component analysis (PCA) and more recently independent component analysis (ICA) are common techniques to extract statistical orthogonal (uncorrelated) and independent modes that represent the maximum variance of observations, respectively. PCA and ICA can be classified as stationary signal decomposition techniques since they are based on decomposing the auto-covariance matrix or diagonalizing higher (than two)-order statistical tensors from centered time series. However, the stationary assumption is obviously not justifiable for many geophysical and climate variables even after removing cyclic components e.g., the seasonal cycles. In this paper, we present a new decomposition method, the complex independent component analysis (CICA, Forootan, PhD-2014), which can be applied to extract to non-stationary (changing in space and time) patterns from geophysical time series. Here, CICA is derived as an extension of real-valued ICA (Forootan and Kusche, JoG-2012), where we (i) define a new complex data set using a Hilbert transformation. The complex time series contain the observed values in their real part, and the temporal rate of variability in their imaginary part. (ii) An ICA algorithm based on diagonalization of fourth-order cumulants is then applied to decompose the new complex data set in (i

  17. Metal ion complexation properties of fulvic acids extracted from composted sewage sludge as compared to a soil fulvic acid.

    PubMed

    Esteves da Silva, Joaquim C G; Oliveira, César J S

    2002-07-01

    Complexation properties of an anthropogenic fulvic acid (FA) extracted from a composted sewage sludge (csFA) for Cu(II), Pb(II) and Cd(II) were studied at pH=6 and at a concentration of 25 mg L(-1). For the case of Cu(II), a particular analysis of the complexation phenomena was done at pH values of 3, 4, 5 and 6 and at aqueous FA concentrations of 25, 50 and 100 mg L(-1) by synchronous excitation molecular fluorescence spectroscopy (SyF). Potentiometric titrimetry with Cu(II), Pb(II), Cd(II) and H+ ion-selective electrodes and acid-base conductimetric titrations were used to obtain experimental information about the acid properties and complexation phenomena. A comparison of the results obtained for csFA with a natural soil FA (sFA) was made. Differences have been detected in the structural composition of the two samples and in the structure of the binding sites. In the csFA, binding site structures containing nitrogen probably play an important role in the complexation, besides oxygen containing structures. Complexation by sFA is mainly due to carboxylic and phenolic structures. Nevertheless, this work shows that csFA have macroscopic complexation properties (magnitude of the conditional stability constant and binding sites concentration) somewhat similar to the natural sFA samples. PMID:12188141

  18. Development of a new DNA extraction protocol for PFGE typing of Mycobacterium tuberculosis complex.

    PubMed

    Ghodousi, Arash; Arash, Ghodousi A; Vatani, S; Darban-Sarokhalil, Davood; Omrani, Maryam; Fooladi, A; Fooladi, Aa; Khosaravi, A; Khosaravi, Ad; Feizabadi, Mohammad Mehdi

    2012-03-01

    A modified pulsed-field gel electrophoresis (PFGE) protocol was developed and applied to clinical isolates of Mycobacterium tuberculosis complex to reduce the cost of using lyticase. This protocol reduces the expense of PFGE typing of Mycobacterium tuberculosis complex as it removes the use of lyticase during the spheroplast formation from these bacteria. PMID:22783461

  19. Development of a new DNA extraction protocol for PFGE typing of Mycobacterium tuberculosis complex

    PubMed Central

    Arash, Ghodousi A; Vatani, S; Darban-Sarokhalil, Davood; Omrani, Maryam; Fooladi, AA; Khosaravi, AD; Feizabadi, Mohammad Mehdi

    2012-01-01

    A modified pulsed-field gel electrophoresis (PFGE) protocol was developed and applied to clinical isolates of Mycobacterium tuberculosis complex to reduce the cost of using lyticase. This protocol reduces the expense of PFGE typing of Mycobacterium tuberculosis complex as it removes the use of lyticase during the spheroplast formation from these bacteria. PMID:22783461

  20. Ion binding compounds, radionuclide complexes, methods of making radionuclide complexes, methods of extracting radionuclides, and methods of delivering radionuclides to target locations

    DOEpatents

    Chen, Xiaoyuan; Wai, Chien M.; Fisher, Darrell R.

    2000-01-01

    The invention pertains to compounds for binding lanthanide ions and actinide ions. The invention further pertains to compounds for binding radionuclides, and to methods of making radionuclide complexes. Also, the invention pertains to methods of extracting radionuclides. Additionally, the invention pertains to methods of delivering radionuclides to target locations. In one aspect, the invention includes a compound comprising: a) a calix[n]arene group, wherein n is an integer greater than 3, the calix[n]arene group comprising an upper rim and a lower rim; b) at least one ionizable group attached to the lower rim; and c) an ion selected from the group consisting of lanthanide and actinide elements bound to the ionizable group. In another aspect, the invention includes a method of extracting a radionuclide, comprising: a) providing a sample comprising a radionuclide; b) providing a calix[n]arene compound in contact with the sample, wherein n is an integer greater than 3; and c) extracting radionuclide from the sample into the calix[n]arene compound. In yet another aspect, the invention includes a method of delivering a radionuclide to a target location, comprising: a) providing a calix[n]arene compound, wherein n is an integer greater than 3, the calix[n]arene compound comprising at least one ionizable group; b) providing a radionuclide bound to the calix[n]arene compound; and c) providing an antibody attached to the calix[n]arene compound, the antibody being specific for a material found at the target location.

  1. Prototype of a test bench for applied research on Extracted beams of the nuclotron accelerator complex

    NASA Astrophysics Data System (ADS)

    Baldin, A. A.; Berlev, A. I.; Bradnova, V.; Butenko, A. V.; Fedorov, A. N.; Kudashkin, I. V.

    2016-05-01

    The results of the development and testing of elements of a test bench for investigating the impact of accelerated particle beams on biological objects, electronics, and other targets are presented. The systems for beam monitoring and target positioning were tested on extracted argon beams in the framework of experiments on studying the radiation hardness of electronic components.

  2. Radium separation through complexation by aqueous crown ethers and ion exchange or solvent extraction

    SciTech Connect

    Chiarizia, R.; Dietz, M.L.; Horwitz, E.P.; Burnett, W.C.

    1997-11-01

    The effect of three water-soluble, unsubstituted crown ethers (15-crown-5 (15C5), 18-crown-6 (18C6) and 21-crown-7 (21C7)) on the uptake of Ca, Sr, Ba and Ra cations by a sulfonic acid cation exchange resin, and on the extraction of the same cations by xylene solutions of dinonylnaphthalenesulfonic acid (HDNNS) from aqueous hydrochloric acid solutions has been investigated. The crown ethers enhance the sorption of the larger cations by the ion exchange resin, thereby improving the resin selectivity over calcium, a result of a synergistic interaction between the crown ether and the ionic functional groups of the resin. Similarly, the extraction of the larger alkaline earth cations into xylene by HDNNS is strongly synergized by the presence of the crown ethers in the aqueous phase. Promising results for intra-Group IIa cation separations have been obtained using each of the three crown ethers as the aqueous ligands and the sulfonic acid cation exchange resin. Even greater separation factors for the radium-calcium couple have been measured with the crown-ethers and HDNNS solutions in the solvent extraction mode. The application of the uptake and extraction results to the development of radium separation schemes is discussed and a possible flowchart for the determination of {sup 226}Ra/{sup 228}Ra in natural waters is presented.

  3. Automated detection of feeding strikes by larval fish using continuous high-speed digital video: a novel method to extract quantitative data from fast, sparse kinematic events.

    PubMed

    Shamur, Eyal; Zilka, Miri; Hassner, Tal; China, Victor; Liberzon, Alex; Holzman, Roi

    2016-06-01

    Using videography to extract quantitative data on animal movement and kinematics constitutes a major tool in biomechanics and behavioral ecology. Advanced recording technologies now enable acquisition of long video sequences encompassing sparse and unpredictable events. Although such events may be ecologically important, analysis of sparse data can be extremely time-consuming and potentially biased; data quality is often strongly dependent on the training level of the observer and subject to contamination by observer-dependent biases. These constraints often limit our ability to study animal performance and fitness. Using long videos of foraging fish larvae, we provide a framework for the automated detection of prey acquisition strikes, a behavior that is infrequent yet critical for larval survival. We compared the performance of four video descriptors and their combinations against manually identified feeding events. For our data, the best single descriptor provided a classification accuracy of 77-95% and detection accuracy of 88-98%, depending on fish species and size. Using a combination of descriptors improved the accuracy of classification by ∼2%, but did not improve detection accuracy. Our results indicate that the effort required by an expert to manually label videos can be greatly reduced to examining only the potential feeding detections in order to filter false detections. Thus, using automated descriptors reduces the amount of manual work needed to identify events of interest from weeks to hours, enabling the assembly of an unbiased large dataset of ecologically relevant behaviors. PMID:26994179

  4. Early folding events during light harvesting complex II assembly in vitro monitored by pulsed electron paramagnetic resonance.

    PubMed

    Fehr, Niklas; García-Rubio, Inés; Jeschke, Gunnar; Paulsen, Harald

    2016-06-01

    Efficient energy transfer in the major light harvesting complex II (LHCII) of green plants is facilitated by the precise alignment of pigments due to the protein matrix they are bound to. Much is known about the import of the LHCII apoprotein into the chloroplast via the TOC/TIC system and its targeting to the thylakoid membrane but information is sparse about when and where the pigments are bound and how this is coordinated with protein folding. In vitro, the LHCII apoprotein spontaneously folds and binds its pigments if the detergent-solubilized protein is combined with a mixture of chlorophylls a and b and carotenoids. In the present work, we employed this approach to study apoprotein folding and pigment binding in a time-resolved manner by using pulsed electron paramagnetic resonance (EPR). Intra-molecular distances were measured before folding, after 255 ms and 40 s folding time in the absence of cryoprotectant, and in the fully folded and assembled LHCII. In accordance with earlier results, the most of the folding of the three membrane-spanning alpha helices precedes their apposition into the final tertiary structure. However, their formation follows different kinetics, partially extending into the final phase of LHCII formation during which much of the condensation of the pigment-protein structure occurs, presumably governed by the binding of chlorophyll b. A rough timetable is proposed to sort partial events into the LHCII formation process. PMID:27063475

  5. Extraction chromatography of palladium and platinum complexes with nitroso-R-salt.

    PubMed

    Flieger, A; Przeszlakowski, S

    1985-12-01

    The retention of palladium and platinum complexes with nitroso-R-salt on silica gel treated with Aliquat 336 has been investigated. The complexation of platinum with nitroso-R-salt (NRS) requires heating of H(2)PtCl(6) with an excess of NRS at 100 degrees . The affinity of the complexes for an Aliquat 336 stationary phase increases in the following order: PdCl(4)(2-) ~ Pt-NRS < PtCl(6)(2-) Pd-NRS. The complexes of palladium and platinum can be separated by column chromatography on silica treated with Aliquat 336 and eluted with 0.25M perchloric acid (Pt) and 1M perchloric acid (Pd). PMID:18963969

  6. Preparation and characterization of inclusion complex of benzyl isothiocyanate extracted from papaya seed with β-cyclodextrin.

    PubMed

    Li, Wenzhao; Liu, Xiaoyu; Yang, Qingfeng; Zhang, Ning; Du, Yideng; Zhu, Huaping

    2015-10-01

    The inclusion complex of benzyl isothiocyanate (BITC), extracted from papaya seed with β-cyclodextrin (β-CD), was prepared. Different analytical techniques, such as Fourier transform infrared spectroscopy, thermal analysis, X-ray diffractometry, particle size distribution analysis and (1)H Nuclear magnetic resonance analysis, were used to investigate the characterization of the inclusion complex (BITC-β-CD). All these approaches indicated that the inclusion complex was capable of being formed. The inclusion complex exhibited different spectroscopic and thermodynamic features and properties from BITC, and we deduced the possible inclusion modes for BITC-β-CD. The calculated apparent stability constant of the BITC-β-CD was 600.8l/mol, and the aqueous solubility of BITC was indistinctively improved by phase solubility studies. The results illustrated that β-CD was a proper excipient for increasing the stability and controlled release of BITC. Thus, β-CD complexation technology would be a promising approach, in expanding the application of BITC as a food antibacterial agent. PMID:25872431

  7. Neuroimaging measures of error-processing: Extracting reliable signals from event-related potentials and functional magnetic resonance imaging.

    PubMed

    Steele, Vaughn R; Anderson, Nathaniel E; Claus, Eric D; Bernat, Edward M; Rao, Vikram; Assaf, Michal; Pearlson, Godfrey D; Calhoun, Vince D; Kiehl, Kent A

    2016-05-15

    Error-related brain activity has become an increasingly important focus of cognitive neuroscience research utilizing both event-related potentials (ERPs) and functional magnetic resonance imaging (fMRI). Given the significant time and resources required to collect these data, it is important for researchers to plan their experiments such that stable estimates of error-related processes can be achieved efficiently. Reliability of error-related brain measures will vary as a function of the number of error trials and the number of participants included in the averages. Unfortunately, systematic investigations of the number of events and participants required to achieve stability in error-related processing are sparse, and none have addressed variability in sample size. Our goal here is to provide data compiled from a large sample of healthy participants (n=180) performing a Go/NoGo task, resampled iteratively to demonstrate the relative stability of measures of error-related brain activity given a range of sample sizes and event numbers included in the averages. We examine ERP measures of error-related negativity (ERN/Ne) and error positivity (Pe), as well as event-related fMRI measures locked to False Alarms. We find that achieving stable estimates of ERP measures required four to six error trials and approximately 30 participants; fMRI measures required six to eight trials and approximately 40 participants. Fewer trials and participants were required for measures where additional data reduction techniques (i.e., principal component analysis and independent component analysis) were implemented. Ranges of reliability statistics for various sample sizes and numbers of trials are provided. We intend this to be a useful resource for those planning or evaluating ERP or fMRI investigations with tasks designed to measure error-processing. PMID:26908319

  8. Extracting Complex Refractive Index from Polycrystalline Glucose with Self-Referenced Method for Terahertz Time-Domain Reflection Spectroscopy.

    PubMed

    Zhang, Yu; Zhang, Lin; Sun, Ping; He, Yingfeng; Zou, Yun; Deng, Yuqiang

    2016-07-01

    A self-referenced method for extracting the complex refractive index of material was proposed. The method utilized signals reflected from the front and rear surfaces of a slice sample as reference and sample signals, respectively. Before using the self-referenced method, a hybrid filtering technique for eliminating systematic and random noises of time-domain terahertz reflection spectroscopy was used. A terahertz reflection spectrum of crystalline glucose was measured and three feature absorption peaks were obtained from 0.2 to 2.0 THz. We suggest that intermolecular vibrational modes may contribute to the observed absorption spectra in the THz frequency range. PMID:27412185

  9. Complex Formation in a Liquid-Liquid Extraction System Containing Co(II), 4-(2-Thiazolylazo)resorcinol and Monotetrazolium Salt.

    PubMed

    Divarova, Vidka; Stojnova, Kirila; Racheva, Petya; Lekova, Vanya

    2016-01-01

    The ion-associated complex formed between anionic chelate of Co(II)-4-(2-Thiazolylazo)resorcinol (TAR) with the monotetrazolium cation of 2-(4-Iodophenyl)-3-(4-nitrophenyl)-5-phenyl-2H-tetrazolium chloride (INT) in the liquid-liquid extraction system Co(II)-TAR-INT-H(2)O-CHCl(3) was studied by the spectrophotometric method. The optimum extraction conditions of Co(II) were found. The extraction equilibria were studied. The equilibrium constants, the recovery factor and some analytical characteristics were calculated. The validity of Beer's law was checked. The molar ratio of the components in the ternary ion-associated complex Co(II)-TAR-INT was determined. The general formula of the complex was suggested. The effect of various foreign ions and reagents on the process of complex formation in the liquid-liquid extraction system was studied. PMID:26970793

  10. Attentional bias to affective faces and complex IAPS images in early visual cortex follows emotional cue extraction.

    PubMed

    Bekhtereva, Valeria; Craddock, Matt; Müller, Matthias M

    2015-05-15

    Emotionally arousing stimuli are known to rapidly draw the brain's processing resources, even when they are task-irrelevant. The steady-state visual evoked potential (SSVEP) response, a neural response to a flickering stimulus which effectively allows measurement of the processing resources devoted to that stimulus, has been used to examine this process of attentional shifting. Previous studies have used a task in which participants detected periods of coherent motion in flickering random dot kinematograms (RDKs) which generate an SSVEP, and found that task-irrelevant emotional stimuli withdraw more attentional resources from the task-relevant RDKs than task-irrelevant neutral stimuli. However, it is not clear whether the emotion-related differences in the SSVEP response are conditional on higher-level extraction of emotional cues as indexed by well-known event-related potential (ERPs) components (N170, early posterior negativity, EPN), or if affective bias in competition for visual attention resources is a consequence of a time-invariant shifting process. In the present study, we used two different types of emotional distractors - IAPS pictures and facial expressions - for which emotional cue extraction occurs at different speeds, being typically earlier for faces (at ~170ms, as indexed by the N170) than for IAPS images (~220-280ms, EPN). We found that emotional modulation of attentional resources as measured by the SSVEP occurred earlier for faces (around 180ms) than for IAPS pictures (around 550ms), after the extraction of emotional cues as indexed by visual ERP components. This is consistent with emotion related re-allocation of attentional resources occurring after emotional cue extraction rather than being linked to a time-fixed shifting process. PMID:25818682

  11. Complex mixture analysis of organic compounds in green coffee bean extract by two-dimensional NMR spectroscopy.

    PubMed

    Wei, Feifei; Furihata, Kazuo; Hu, Fangyu; Miyakawa, Takuya; Tanokura, Masaru

    2010-11-01

    A complex mixture analysis by one- and two-dimensional nuclear magnetic resonance (NMR) spectroscopy was carried out for the first time for the identification and quantification of organic compounds in green coffee bean extract (GCBE). A combination of (1)H-(1)H DQF-COSY, (1)H-(13)C HSQC, and (1)H-(13)C CT-HMBC two-dimensional sequences was used, and 16 compounds were identified. In particular, three isomers of caffeoylquinic acid were identified in the complex mixture without any separation. In addition, GCBE components were quantified by the integration of carbon signals by use of a relaxation reagent and an inverse-gated decoupling method without a nuclear Overhauser effect. This NMR methodology provides detailed information about the kinds and amounts of GCBE components, and in our study, the chemical makeup of GCBE was clarified by the NMR results. PMID:20818806

  12. A drug-adverse event extraction algorithm to support pharmacovigilance knowledge mining from PubMed citations.

    PubMed

    Wang, Wei; Haerian, Krystl; Salmasian, Hojjat; Harpaz, Rave; Chase, Herbert; Friedman, Carol

    2011-01-01

    Adverse drug events (ADEs) create a serious problem causing substantial harm to patients. An executable standardized knowledgebase of drug-ADE relations which is publicly available would be valuable so that it could be used for ADE detection. The literature is an important source that could be used to generate a knowledgebase of drug-ADE pairs. In this paper, we report on a method that automatically determines whether a specific adverse event (AE) is caused by a specific drug based on the content of PubMed citations. A drug-ADE classification method was initially developed to detect neutropenia based on a pre-selected set of drugs. This method was then applied to a different set of 76 drugs to determine if they caused neutropenia. For further proof of concept this method was applied to 48 drugs to determine whether they caused another AE, myocardial infarction. Results showed that AUROC was 0.93 and 0.86 respectively. PMID:22195210

  13. Leadership within Emergent Events in Complex Systems: Micro-Enactments and the Mechanisms of Organisational Learning and Change

    ERIC Educational Resources Information Center

    Hazy, James K.; Silberstang, Joyce

    2009-01-01

    One tradition within the complexity paradigm considers organisations as complex adaptive systems in which autonomous individuals interact, often in complex ways with difficult to predict, non-linear outcomes. Building upon this tradition, and more specifically following the complex systems leadership theory approach, we describe the ways in which…

  14. Role extraction in complex networks and its application in control of networks

    NASA Astrophysics Data System (ADS)

    Zhou, Mingyang; He, Xingsheng; Fu, Zhongqian; Zhuo, Zhao

    2016-01-01

    Given a large network, dynamics of the network are determined by both nodes' features and network connections. Some features could be extracted from node labels and other kinds of priori knowledge. But how to perform the feature classification without priori knowledge is a challenge. This paper addresses the key problem: how do we conduct role extraction in networks with only edge connections known? On the basis of behavior differences in dynamics, nodes are classified into three role groups: Leaders(L), Communicators(C) and Members(M). Unlike traditional community detections, we detect overlapping communities by link clustering first and then classify nodes according to the community entropy, which describes the disorder of how many different communities a node connects to. We propose a time saving and unsupervised learning approach for automatically discovering nodes' roles based solely on network topology. The effectiveness of this method is demonstrated on six real-world networks through pinning control. By controlling communicator nodes, the controllability is enhanced and the cost for control is reduced obviously in networks with strong community structure.

  15. Development and characterization of a new polyampholyte-surfactant complex applied to the solid phase extraction of bisphenol-A.

    PubMed

    Martínez, J M Lázaro; Denis, M F Leal; Denaday, L R; Dall' Orto, V Campo

    2009-12-15

    This paper presents a material that has both hydrophilic and hydrophobic domains, obtained by combination of a polyampholyte with a surfactant. This material was fully characterized by different spectroscopic techniques and microscopy. Bisphenol-A (BPA) was chosen as a model molecule to study the interaction with compounds of intermediate polarity. We explored the kinetics and equilibrium of BPA on the surface of the polyampholyte-surfactant complex and found a significantly high loading capacity (2.02 mmol g(-1)) and complete binding from solutions at concentration levels below 100 micromol L(-1). The complex was encapsulated in agarose gel to be used as solid phase for extraction of BPA from food simulants in contact with polycarbonate bottles under different treatments. Bisphenol was preconcentrated, extracted and analysed by liquid chromatography with an amperometric detector. The instrumental detection limit of the technique was 10 microg L(-1), which was lowered to 0.14 microg L(-1) by the preconcentration step. The BPA released from baby bottles was 2.1 ng cm(-2) (sigma(n-1): 0.1) in the first use with distilled water. PMID:19836553

  16. Human cytochrome p450 inhibition and metabolic-intermediate complex formation by goldenseal extract and its methylenedioxyphenyl components.

    PubMed

    Chatterjee, Parnali; Franklin, Michael R

    2003-11-01

    The concurrent use of herbal medicinals with prescription and over-the-counter drugs carries a risk for unanticipated adverse drug-botanical pharmacokinetic interactions, particularly as a result of cytochrome P450 (P450) inhibition. Extracts of goldenseal (Hydrastis canadensis) containing approximately equal concentrations ( approximately 17 mM) of two methylenedioxyphenyl alkaloids, berberine and hydrastine, inhibited with increasing potency (CYP2C9) diclofenac 4'-hydroxylation, (CYP2D6) bufuralol 1'-hydroxylation, and (CYP3A4) testosterone 6beta-hydroxylation activities in human hepatic microsomes. The inhibition of testosterone 6beta-hydroxylation activity was noncompetitive with an apparent Ki of 0.11% extract. Of the methylenedioxyphenyl alkaloids, berberine (IC50 = 45 microM) was the more inhibitory toward bufuralol 1'-hydroxylation and hydrastine (IC50 approximately 350 microM for both isomers), toward diclofenac 4'-hydroxylation. For testosterone 6beta-hydroxylation, berberine was the least inhibitory component (IC50 approximately 400 microM). Hydrastine inhibited testosterone 6beta-hydroxylation with IC50 values for the (+)- and (-)-isomers of 25 and 30 microM, respectively. For (-)-hydrastine, an apparent Ki value of 18 microM without preincubation and an NADPH-dependent mechanism-based inhibition with a kinactivation of 0.23 min(-1) and a KI of approximately 110 microM were determined. Cytochrome P450 metabolic-intermediate (MI) complex formation could be demonstrated for both hydrastine isomers. With expressed P450 isoforms, hydrastine formed a P450 MI complex with CYP2C9, CYP2D6, and CYP3A4. Coexpression of cytochrome b5 with the P450 isoforms enhanced the rate but not the extent of P450 MI complex formation. PMID:14570772

  17. Kurtosis-Based Blind Source Extraction of Complex Non-Circular Signals with Application in EEG Artifact Removal in Real-Time

    PubMed Central

    Javidi, Soroush; Mandic, Danilo P.; Took, Clive Cheong; Cichocki, Andrzej

    2011-01-01

    A new class of complex domain blind source extraction algorithms suitable for the extraction of both circular and non-circular complex signals is proposed. This is achieved through sequential extraction based on the degree of kurtosis and in the presence of non-circular measurement noise. The existence and uniqueness analysis of the solution is followed by a study of fast converging variants of the algorithm. The performance is first assessed through simulations on well understood benchmark signals, followed by a case study on real-time artifact removal from EEG signals, verified using both qualitative and quantitative metrics. The results illustrate the power of the proposed approach in real-time blind extraction of general complex-valued sources. PMID:22319461

  18. The composition of peridotite tectonites from the Ivrea Complex, northern Italy - Residues from melt extraction

    NASA Astrophysics Data System (ADS)

    Hartmann, Gerald; Wedepohl, K. H.

    1993-04-01

    Results are presented of analyses of forty-three samples from three peridotite tectonites (Balmuccia, Baldissero, and Finero) from the Ivrea Complex (northern Italy) for major elements, forty minor elements, and mineral composition. A subset of samples was also investigated with respect to delta D, delta (O-18), delta (S-34), and Sr-87/Sr-86 ratios. The results disagree with the report of Ernst (1978) on Al and on modal compositions in peridotites from the same localities. The nature of the three samples from the Balmuccia/Baldissero and Finero is discussed.

  19. CLaSPS: A NEW METHODOLOGY FOR KNOWLEDGE EXTRACTION FROM COMPLEX ASTRONOMICAL DATA SETS

    SciTech Connect

    D'Abrusco, R.; Fabbiano, G.; Laurino, O.; Djorgovski, G.; Donalek, C.; Longo, G.

    2012-08-20

    In this paper, we present the Clustering-Labels-Score Patterns Spotter (CLaSPS), a new methodology for the determination of correlations among astronomical observables in complex data sets, based on the application of distinct unsupervised clustering techniques. The novelty in CLaSPS is the criterion used for the selection of the optimal clusterings, based on a quantitative measure of the degree of correlation between the cluster memberships and the distribution of a set of observables, the labels, not employed for the clustering. CLaSPS has been primarily developed as a tool to tackle the challenging complexity of the multi-wavelength complex and massive astronomical data sets produced by the federation of the data from modern automated astronomical facilities. In this paper, we discuss the applications of CLaSPS to two simple astronomical data sets, both composed of extragalactic sources with photometric observations at different wavelengths from large area surveys. The first data set, CSC+, is composed of optical quasars spectroscopically selected in the Sloan Digital Sky Survey data, observed in the x-rays by Chandra and with multi-wavelength observations in the near-infrared, optical, and ultraviolet spectral intervals. One of the results of the application of CLaSPS to the CSC+ is the re-identification of a well-known correlation between the {alpha}{sub OX} parameter and the near-ultraviolet color, in a subset of CSC+ sources with relatively small values of the near-ultraviolet colors. The other data set consists of a sample of blazars for which photometric observations in the optical, mid-, and near-infrared are available, complemented for a subset of the sources, by Fermi {gamma}-ray data. The main results of the application of CLaSPS to such data sets have been the discovery of a strong correlation between the multi-wavelength color distribution of blazars and their optical spectral classification in BL Lac objects and flat-spectrum radio quasars, and a

  20. Modelling large solar proton events with the shock-and-particle model. Extraction of the characteristics of the MHD shock front at the cobpoint

    NASA Astrophysics Data System (ADS)

    Pomoell, Jens; Aran, Angels; Jacobs, Carla; Rodríguez-Gasén, Rosa; Poedts, Stefaan; Sanahuja, Blai

    2015-06-01

    We have developed a new version of a model that combines a two-dimensional Sun-to-Earth magnetohydrodynamic (MHD) simulation of the propagation of a CME-driven shock and a simulation of the transport of particles along the interplanetary magnetic field (IMF) line connecting the shock front and the observer. We assume that the shock-accelerated particles are injected at the point along the shock front that intersects this IMF line, i.e. at the cobpoint. Novel features of the model are an improved solar wind model and an enhanced fully automated algorithm to extract the necessary plasma characteristics from the shock simulation. In this work, the new algorithms have been employed to simulate the 2000 April 4 and the 2006 December 13 SEP events. In addition to quantifying the performance of the new model with respect to results obtained using previous versions of the shock-and-particle model, we investigate the semi-empirical relation between the injection rate of shock-accelerated particles, Q, and the jump in speed across the shock, VR, known as the Q(VR) relation. Our results show that while the magnetic field and density compression at the shock front is markedly different than in our previous modeling, the evolution of VR remains largely similar. As a result, we confirm that a simple relation can still be established between Q and VR, which enables the computation of synthetic intensity-time profiles at any location in interplanetary space. Furthermore, the new shock extraction tool is found to yield improved results being in general more robust. These results are important not only with regard to efforts to develop coupled magnetohydrodynamic and particle simulation models, but also to improve space weather related software tools that aim to predict the peak intensities, fluences and proton intensity-time profiles of SEP events (such as the SOLPENCO tool).

  1. [Methods for extraction of exopolymeric complex in plankton and biofilm growth mode of Stenotrophomonas maltophilia 22M].

    PubMed

    Boretskaia, M A; Suslova, O S

    2013-01-01

    The optimal methods for the extraction of exopolymeric complex (EPS) of Stenotrophomonas maltophilia 22M was determined. That EPS was synthesized in plankton and biofilm growth mode on the mild steel surface. It is desirable to use different physical and chemical methods for studying the EPS composition (carbohydrates and proteins) depending on the bacteria growth mode. In this way the interaction with ion exchange resin was the most effective for plankton growth mode to determine the maximum amount of carbohydrates (9.5 microg/ml), and the impact of heating to determine protein (3.9 microg/ml). For EPS biofilm in order to obtain maximum amount of carbohydrate it is desirable to use heating (30 microg/ml) and centrifugation (35 microg/ml). It is recommended to determine protein in the biofilm EPS after treatment with heating (3.75 microg/ml) and centrifugation (3.75 microg/ml). PMID:23720963

  2. Solid-phase extraction strategies to surmount body fluid sample complexity in high-throughput mass spectrometry-based proteomics.

    PubMed

    Bladergroen, Marco R; van der Burgt, Yuri E M

    2015-01-01

    For large-scale and standardized applications in mass spectrometry- (MS-) based proteomics automation of each step is essential. Here we present high-throughput sample preparation solutions for balancing the speed of current MS-acquisitions and the time needed for analytical workup of body fluids. The discussed workflows reduce body fluid sample complexity and apply for both bottom-up proteomics experiments and top-down protein characterization approaches. Various sample preparation methods that involve solid-phase extraction (SPE) including affinity enrichment strategies have been automated. Obtained peptide and protein fractions can be mass analyzed by direct infusion into an electrospray ionization (ESI) source or by means of matrix-assisted laser desorption ionization (MALDI) without further need of time-consuming liquid chromatography (LC) separations. PMID:25692071

  3. Extracting meaning from complex data: Processing, display, interaction; Proceedings of the Meeting, Santa Clara, CA, Feb. 14-16, 1990

    SciTech Connect

    Farrell, E.J.

    1990-01-01

    The present conference on extracting meaning from complex data emphasizes processing, display, and interaction, and encompasses volume visualization, software systems for data interpretation, interfaces for volumetric interpretation, sound and images for data presentation, multiple variable techniques, applications, and data structures. Specific issues addressed include a level surface cutting-plane program for fluid-flow data, 3D data visualization using DSP meshes, data analysis and visualization tools, a 3D interactive physically based microworld, the auditory presentation of experimental data, and tools for the interpretation of multispectral data. Also addressed are the visualization of processes near a black hole, sphere quadtrees, an integrated image database system on a local area network, and scientific visualization at the Center for the Analysis and Prediction of Storms.

  4. Selection of Suitable DNA Extraction Methods for Genetically Modified Maize 3272, and Development and Evaluation of an Event-Specific Quantitative PCR Method for 3272.

    PubMed

    Takabatake, Reona; Masubuchi, Tomoko; Futo, Satoshi; Minegishi, Yasutaka; Noguchi, Akio; Kondo, Kazunari; Teshima, Reiko; Kurashima, Takeyo; Mano, Junichi; Kitta, Kazumi

    2016-01-01

    A novel real-time PCR-based analytical method was developed for the event-specific quantification of a genetically modified (GM) maize, 3272. We first attempted to obtain genome DNA from this maize using a DNeasy Plant Maxi kit and a DNeasy Plant Mini kit, which have been widely utilized in our previous studies, but DNA extraction yields from 3272 were markedly lower than those from non-GM maize seeds. However, lowering of DNA extraction yields was not observed with GM quicker or Genomic-tip 20/G. We chose GM quicker for evaluation of the quantitative method. We prepared a standard plasmid for 3272 quantification. The conversion factor (Cf), which is required to calculate the amount of a genetically modified organism (GMO), was experimentally determined for two real-time PCR instruments, the Applied Biosystems 7900HT (the ABI 7900) and the Applied Biosystems 7500 (the ABI7500). The determined Cf values were 0.60 and 0.59 for the ABI 7900 and the ABI 7500, respectively. To evaluate the developed method, a blind test was conducted as part of an interlaboratory study. The trueness and precision were evaluated as the bias and reproducibility of the relative standard deviation (RSDr). The determined values were similar to those in our previous validation studies. The limit of quantitation for the method was estimated to be 0.5% or less, and we concluded that the developed method would be suitable and practical for detection and quantification of 3272. PMID:26936302

  5. Characterization of solid-phase extraction of Fe(III) by unloaded polyurethane foam as thiocyanate complex.

    PubMed

    de Almeida, Gil Nunes; de Sousa, Leandro M; Pereira Netto, Annibal D; Cassella, Ricardo J

    2007-11-01

    This work presents a detailed study about the adsorption of iron(III)-thiocyanate complexes onto unloaded polyether-type polyurethane foam (PUF). A novel strategy was employed for this purpose, utilizing the adjustment of the plug cylinder of PUF to the arm of an overhead stirrer. The system was characterized in relation to equilibrium and kinetic aspects and it was modeled by applying Langmuir and Freundlich isotherms. The results obtained showed that adsorption occurs on a monolayer and that external transport of the solute from solution to adsorbent was the rate-determining mechanism. A maximum adsorption capacity of 2.06 x 10(-4) mol Fe g(-1) was obtained under established experimental conditions (0.5 mol L(-1) SCN(-) and 0.005 mol L(-1) HCl). Sequential extraction experiments were carried out by changing PUF in time intervals previously defined (5, 20, and 40 min), and the obtained results showed that it is possible to remove around 95% of the Fe(III) in solution through five consecutive extractions of 5 min with five 200 mg PUF cylinders. PMID:17662992

  6. Extraction of uranium and lead from mixed waste debris using a variety of metal/ligand complexes

    SciTech Connect

    Needham, D.A.; Duran, B.L.; Ehler, D.S.; Sauer, N.N.

    1997-12-31

    To ensure the safety of our Nation`s nuclear stockpile, Los Alamos National Laboratory is in the process of constructing the DARHT (Dual Axis Radiographic Hydrodynamic Test) facility. DARHT will examine the effects of aging and the stability of our stockpile. Contained testing will be phased in to reduce the impact of these tests, which contain depleted uranium, on our environment. The main focus of this research is to develop a treatment scheme for the recovery of depleted uranium and lead from shot debris that will result from these tests. The goals of this research are to optimize the conditions on a bench scale using a commercially available water soluble polymer to bind the lead and a variety of metal/ligand complexes such as 4,5-dihydroxy-1,3-benzene-disulfonic acid, dithionite, sodium carbonate/bicarbonate, and sodium hypochlorite to bind the uranium. Studies were conducted on a mixture of debris, such as wood, cable, paper towels, and tubing that contained both uranium and lead ranging in concentration from 10-1000`s of ppm of contaminants. Experiments were done varying combinations and successions of extractant solutions as well as a number of sequential extractions. Studies show that a mixture of sodium hypochlorite and carbonate removed 90+% of both uranium and lead. We then focused on a separation scheme for the lead and uranium.

  7. Antioxidant/Prooxidant and antibacterial/probacterial effects of a grape seed extract in complex with lipoxygenase.

    PubMed

    Chedea, Veronica Sanda; Braicu, Cornelia; Chirilă, Flore; Ogola, Henry Joseph Oduor; Pelmuş, Rodica Ştefania; Călin, Loredana Georgeta; Socaciu, Carmen

    2014-01-01

    In an attempt to determine the antioxidant/prooxidant, antibacterial/probacterial action of flavan-3-ols and procyanidins from grape seeds, pure catechin (CS), and an aqueous grape seed extract (PE), were applied in the absence and presence of pure lipoxygenase (LS) or in extract (LE) to leucocyte culture, Escherichia coli B 41 and Brevibacterium linens, and observed whether there was any effect on lipid peroxidation, cytotoxicity, or growth rate. Short time periods of coincubation of cells with the polyphenols, followed by the exposure to LS and LE, revealed a high level of lipid peroxidation and a prooxidative effect. Longer coincubation and addition of LS and LE resulted in the reversal of the prooxidant action either to antioxidant activity for CS + LS and PE + LS or to the control level for CS + LE and PE + LE. Lipid peroxidation was significantly reduced when cells were exposed to polyphenols over a longer period. Longer exposure of E. coli to CS or PE followed by addition of LS for 3 h resulted in bactericidal activity. Significant stimulatory effect on microbial growth was observed for PE + LS and PE + LE treatments in B. linens, illustrating the potential probacterial activity in B. linens cultures. Lipoxygenase-polyphenols complex formation was found to be responsible for the observed effects. PMID:25313359

  8. Extractional spectrophotometric analysis of metronidazole, tinidazole, ornidazole and secnidazole bases through acid-dye complexation using bromothymol blue dye.

    PubMed

    Darwish, Khaled M; Salama, Ismail; Mostafa, Samia; El-Sadek, Mohamed

    2012-01-01

    An easy, precise and valid extractional-spectrophotometric technique is described for the assessment of metronidazole (MNZ), tinidazole (TNZ), ornidazole (ONZ) and secnidazole (SNZ) in pure state and in their pharmaceutical formulations. The technique includes first the reduction of above cited drugs using HCl and zinc powder, then the formation of intense yellow colored ion-association complex species (1:3 drug/dye) using bromothymol blue (BTB) in a buffered aqueous acidic medium at pH 3-3.50. The colored products are extracted into dichloromethane and quantitatively determined at 416-420 nm. The experimental operating factors influencing the ion-pairs development were studied and optimized to obtain the maximum color intensity. The Beer plots are obeyed in the concentration ranges 2.50-22.50, 2.50-30, 7.50-35 and 5-30 μgml-1 for MNZ, TNZ, ONZ and SNZ, respectively, with correlation coefficients not less than 0.9995. The proposed technique is recommended for the routine quality control analysis of the investigated drugs in commercial tablets with no observed interference from common pharmaceutical adjuvants. Results of such analysis were statistically validated and through recovery studies, showing excellent agreement with those achieved by the reported techniques. PMID:22186332

  9. Members of the NODE (Nanog and Oct4-associated deacetylase) complex and SOX-2 promote the initiation of a natural cellular reprogramming event in vivo

    PubMed Central

    Kagias, Konstantinos; Ahier, Arnaud; Fischer, Nadine; Jarriault, Sophie

    2012-01-01

    Differentiated cells can be forced to change identity, either to directly adopt another differentiated identity or to revert to a pluripotent state. Direct reprogramming events can also occur naturally. We recently characterized such an event in Caenorhabditis elegans, in which a rectal cell switches to a neuronal cell. Here we have used this single-cell paradigm to investigate the molecular requirements of direct cell-type conversion, with a focus on the early steps. Our genetic analyses revealed the requirement of sem-4/Sall, egl-27/Mta, and ceh-6/Oct, members of the NODE complex recently identified in embryonic stem (ES) cells, and of the OCT4 partner sox-2, for the initiation of this natural direct reprogramming event. These four factors have been shown to individually impact on ES cell pluripotency; however, whether they act together to control cellular potential during development remained an open question. We further found that, in addition to acting at the same time, these factors physically associate, suggesting that they could act together as a NODE-like complex during this in vivo process. Finally, we have elucidated the functional domains in EGL-27/MTA that mediate its reprogramming activity in this system and have found that modulation of the posterior HOX protein EGL-5 is a downstream event to allow the initiation of Y identity change. Our data reveal unique in vivo functions in a natural direct reprogramming event for these genes that impact on ES cells pluripotency and suggest that conserved nuclear events could be shared between different cell plasticity phenomena across phyla. PMID:22493276

  10. Members of the NODE (Nanog and Oct4-associated deacetylase) complex and SOX-2 promote the initiation of a natural cellular reprogramming event in vivo.

    PubMed

    Kagias, Konstantinos; Ahier, Arnaud; Fischer, Nadine; Jarriault, Sophie

    2012-04-24

    Differentiated cells can be forced to change identity, either to directly adopt another differentiated identity or to revert to a pluripotent state. Direct reprogramming events can also occur naturally. We recently characterized such an event in Caenorhabditis elegans, in which a rectal cell switches to a neuronal cell. Here we have used this single-cell paradigm to investigate the molecular requirements of direct cell-type conversion, with a focus on the early steps. Our genetic analyses revealed the requirement of sem-4/Sall, egl-27/Mta, and ceh-6/Oct, members of the NODE complex recently identified in embryonic stem (ES) cells, and of the OCT4 partner sox-2, for the initiation of this natural direct reprogramming event. These four factors have been shown to individually impact on ES cell pluripotency; however, whether they act together to control cellular potential during development remained an open question. We further found that, in addition to acting at the same time, these factors physically associate, suggesting that they could act together as a NODE-like complex during this in vivo process. Finally, we have elucidated the functional domains in EGL-27/MTA that mediate its reprogramming activity in this system and have found that modulation of the posterior HOX protein EGL-5 is a downstream event to allow the initiation of Y identity change. Our data reveal unique in vivo functions in a natural direct reprogramming event for these genes that impact on ES cells pluripotency and suggest that conserved nuclear events could be shared between different cell plasticity phenomena across phyla. PMID:22493276