Concentrating Solar Power Projects - Gansu Akesai 50MW Molten Salt Trough
project | Concentrating Solar Power | NREL Gansu Akesai 50MW Molten Salt Trough project Status . Technology: Parabolic trough Turbine Capacity: Net: 50.0 MW Gross: 50.0 MW Status: Under development Do you have more information, corrections, or comments? Background Technology: Parabolic trough Status: Under
Concentrating Solar Power Projects | Concentrating Solar Power | NREL
construction, or under development. CSP technologies include parabolic trough, linear Fresnel reflector, power Technology-listing by parabolic trough, linear Fresnel reflector, power tower, or dish/engine systems Status
Concentrating Solar Power Projects - Chabei 64MW Molten Salt Parabolic
project Status Date: September 29, 2016 Project Overview Project Name: Chabei 64MW Molten Salt Parabolic Technology: Parabolic trough Turbine Capacity: Net: 64.0 MW Gross: 64.0 MW Status: Under development Do you have more information, corrections, or comments? Background Technology: Parabolic trough Status: Under
Optimized molten salt receivers for ultimate trough solar fields
NASA Astrophysics Data System (ADS)
Riffelmann, Klaus-J.; Richert, Timo; Kuckelkorn, Thomas
2016-05-01
Today parabolic trough collectors are the most successful concentrating solar power (CSP) technology. For the next development step new systems with increased operation temperature and new heat transfer fluids (HTF) are currently developed. Although the first power tower projects have successfully been realized, up to now there is no evidence of an all-dominant economic or technical advantage of power tower or parabolic trough. The development of parabolic trough technology towards higher performance and significant cost reduction have led to significant improvements in competitiveness. The use of molten salt instead of synthetic oil as heat transfer fluid will bring down the levelized costs of electricity (LCOE) even further while providing dispatchable energy with high capacity factors. FLABEG has developed the Ultimate TroughTM (UT) collector, jointly with sbp Sonne GmbH and supported by public funds. Due to its validated high optical accuracy, the collector is very suitable to operate efficiently at elevated temperatures up to 550 °C. SCHOTT will drive the key-innovations by introducing the 4th generation solar receiver that addresses the most significant performance and cost improvement measures. The new receivers have been completely redesigned to provide a product platform that is ready for high temperature operation up to 550 °C. Moreover distinct product features have been introduced to reduce costs and risks in solar field assembly and installation. The increased material and design challenges incurred with the high temperature operation have been reflected in sophisticated qualification and validation procedures.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stettenheim, Joel
Norwich Technologies (NT) is developing a disruptively superior solar field for trough concentrating solar power (CSP). Troughs are the leading CSP technology (85% of installed capacity), being highly deployable and similar to photovoltaic (PV) systems for siting. NT has developed the SunTrap receiver, a disruptive alternative to vacuum-tube concentrating solar power (CSP) receivers, a market currently dominated by the Schott PTR-70. The SunTrap receiver will (1) operate at higher temperature (T) by using an insulated, recessed radiation-collection system to overcome the energy losses that plague vacuum-tube receivers at high T, (2) decrease acquisition costs via simpler structure, and (3) dramaticallymore » increase reliability by eliminating vacuum. It offers comparable optical efficiency with thermal loss reduction from ≥ 26% (at presently standard T) to ≥ 55% (at high T), lower acquisition costs, and near-zero O&M costs.« less
Line-focus concentrating collector program
NASA Technical Reports Server (NTRS)
Dugan, V. L.
1980-01-01
The Line-Focus Concentrating Collector Program has emphasized the development and dissemination of concentrating solar technology in which the reflected sunlight is focused onto a linear or line receiver. Although a number of different types of line-focus concentrators were developed, the parabolic trough has gained the widest acceptance and utilization within the industrial and applications sectors. The trough is best applied for application scenarios which require temperatures between 140 and 600 F. Another concept, the bowl, is investigated for applications which may require temperatures in the range between 600 and 1200 F. Current technology emphases are upon the reduction of system installation cost and the implementation of production oriented engineering.
Reflector Technology Development and System Design for Concentrating Solar Power Technologies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Adam Schaut
2011-12-30
Alcoa began this program in March of 2008 with the goal of developing and validating an advanced CSP trough design to lower the levelized cost of energy (LCOE) as compared to existing glass based, space-frame trough technology. In addition to showing a pathway to a significant LCOE reduction, Alcoa also desired to create US jobs to support the emerging CSP industry. Alcoa's objective during Phase I: Concept Feasibility was to provide the DOE with a design approach that demonstrates significant overall system cost savings without sacrificing performance. Phase I consisted of two major tasks; reflector surface development and system conceptmore » development. Two specific reflective surface technologies were investigated, silver metallized lamination, and thin film deposition both applied on an aluminum substrate. Alcoa prepared samples; performed test validation internally; and provided samples to the NREL for full-spectrum reflectivity measurements. The final objective was to report reflectivity at t = 0 and the latest durability results as of the completion of Phase 1. The target criteria for reflectance and durability were as follows: (1) initial (t = 0), hemispherical reflectance >93%, (2) initial spectral reflectance >90% for 25-mrad reading and >87% for 7-mrad reading, and (3) predicted 20 year durability of less than 5% optical performance drop. While the results of the reflective development activities were promising, Alcoa was unable to down-select on a reflective technology that met the target criteria. Given the progress and potential of both silver film and thin film technologies, Alcoa continued reflector surface development activities in Phase II. The Phase I concept development activities began with acquiring baseline CSP system information from both CSP Services and the DOE. This information was used as the basis to develop conceptual designs through ideation sessions. The concepts were evaluated based on estimated cost and high-level structural performance. The target criteria for the concept development was to achieve a solar field cost savings of 25%-50% thereby meeting or exceeding the DOE solar field cost savings target of $350/m2. After evaluating various structural design approaches, Alcoa down-selected to a monocoque, dubbed Wing Box, design that utilizes the reflective surface as a structural, load carrying member. The cost and performance potential of the Wing Box concept was developed via initial finite element analysis (FEA) and cost modeling. The structural members were sized through material utilization modeling when subjected to representative loading conditions including wind loading. Cost modeling was utilized to refine potential manufacturing techniques that could be employed to manufacture the structural members. Alcoa concluded that an aluminum intensive collector design can achieve significant cost savings without sacrificing performance. Based on the cost saving potential of this Concept Feasibility study, Alcoa recommended further validation of this CSP approach through the execution of Phase II: Design and Prototype Development. Alcoa Phase II objective was to provide the DOE with a validated CSP trough design that demonstrates significant overall system cost savings without sacrificing performance. Phase II consisted of three major tasks; Detail System Design, Prototype Build, and System Validation. Additionally, the reflector surface development that began in Phase I was continued in Phase II. After further development work, Alcoa was unable to develop a reflective technology that demonstrated significant performance or cost benefits compared to commercially available CSP reflective products. After considering other commercially available reflective surfaces, Alcoa selected Alano's MIRO-SUN product for use on the full scale prototype. Although MIRO-SUN has a lower specular reflectivity compared to other options, its durability in terms of handling, cleaning, and long-term reflectivity was deemed the most important attribute to successfully validate Alcoa's advanced trough architecture. To validate the performance of the Wing Box trough, a 6 meter aperture by 14 meter long prototype trough was built. For ease of shipping to and assembly at NREL's test facility, the prototype was fabricated in two half modules and joined along the centerline to create the Wing Box trough. The trough components were designed to achieve high precision of the reflective surface while leveraging high volume manufacturing and assembly techniques.« less
Development of sheet-metal parabolic-trough reflector panels
NASA Astrophysics Data System (ADS)
Biester, A. W.
1982-06-01
Efforts to develop accurate, durable, and mass producible sheet metal parabolic trough solar collectors and the associated support for the collectors are described. The design considered is similar to an automobile hood, a two-piece sheet metal structure consisting of a formed steel frame or stiffening panel and a smooth contoured skin. The two pieces may be bonded or welded to form a rigid structure, and a reflective surface applied such as a film, glass mirror, or any of the presently utilized materials. The work encompassed material selection, adhesive selection and testing, tool design and fabrication, prototype panel production, and design and development of torque tube assemblies on which the trough is inclined. Results of adhesive bonding studies are given. It is found that high volume technology can be used to produce accurate and structurally sound reflector panels, and one configuration was selected for fabrication in suitable quantities for performance testing.
Concentrating Solar Power Projects - Casablanca | Concentrating Solar Power
(Badajoz) Owner(s): ACS - COBRA group (100%) Technology: Parabolic trough Turbine Capacity: Net: 50.0 MW Participants Developer(s): ACS - COBRA group Owner(s) (%): ACS - COBRA group (100%) EPC Contractor: Cobra
LCOE reduction potential of parabolic trough and solar tower CSP technology until 2025
NASA Astrophysics Data System (ADS)
Dieckmann, Simon; Dersch, Jürgen; Giuliano, Stefano; Puppe, Michael; Lüpfert, Eckhard; Hennecke, Klaus; Pitz-Paal, Robert; Taylor, Michael; Ralon, Pablo
2017-06-01
Concentrating Solar Power (CSP), with an installed capacity of 4.9 GW by 2015, is a young technology compared to other renewable power generation technologies. A limited number of plants and installed capacity in a small challenging market environment make reliable and transparent cost data for CSP difficult to obtain. The International Renewable Energy Agency (IRENA) and the DLR German Aerospace Center gathered and evaluated available cost data from various sources for this publication in order to yield transparent, reliable and up-to-date cost data for a set of reference parabolic trough and solar tower plants in the year 2015 [1]. Each component of the power plant is analyzed for future technical innovations and cost reduction potential based on current R&D activities, ongoing commercial developments and growth in market scale. The derived levelized cost of electricity (LCOE) for 2015 and 2025 are finally contrasted with published power purchase agreements (PPA) of the NOOR II+III power plants in Morocco. At 7.5% weighted average cost of capital (WACC) and 25 years economic life time, the levelized costs of electricity for plants with 7.5 (trough) respectively 9 (tower) full-load hours thermal storage capacity decrease from 14-15 -ct/kWh today to 9-10 -ct/kWh by 2025 for both technologies at direct normal irradiation of 2500 kWh/(m².a). The capacity factor increases from 41.1% to 44.6% for troughs and from 45.5% to 49.0% for towers. Financing conditions are a major cost driver and offer potential for further cost reduction with the maturity of the technology and low interest rates (6-7 - ct/kWh for 2% WACC at 2500 kWh/(m2.a) in 2025).
DOE Office of Scientific and Technical Information (OSTI.GOV)
May, E. K.; Forristall, R.
2005-11-01
Industrial Solar Technology has assembled a team of experts to develop a large-aperture parabolic trough for the electric power market that moves beyond cost and operating limitations of 1980's designs based on sagged glass reflectors. IST's structurally efficient space frame design will require nearly 50% less material per square meter than a Solel LS-2 concentrator and the new trough will rotate around the focal point. This feature eliminates flexhoses that increase pump power, installation and maintenance costs. IST aims to deliver a concentrator module costing less than $100 per square meter that can produce temperatures up to 400 C. Themore » IST concentrator is ideally suited for application of front surface film reflectors and ensures that US corporations will manufacture major components, except for the high temperature receivers.« less
On purpose simulation model for molten salt CSP parabolic trough
NASA Astrophysics Data System (ADS)
Caranese, Carlo; Matino, Francesca; Maccari, Augusto
2017-06-01
The utilization of computer codes and simulation software is one of the fundamental aspects for the development of any kind of technology and, in particular, in CSP sector for researchers, energy institutions, EPC and others stakeholders. In that extent, several models for the simulation of CSP plant have been developed with different main objectives (dynamic simulation, productivity analysis, techno economic optimization, etc.), each of which has shown its own validity and suitability. Some of those models have been designed to study several plant configurations taking into account different CSP plant technologies (Parabolic trough, Linear Fresnel, Solar Tower or Dish) and different settings for the heat transfer fluid, the thermal storage systems and for the overall plant operating logic. Due to a lack of direct experience of Molten Salt Parabolic Trough (MSPT) commercial plant operation, most of the simulation tools do not foresee a suitable management of the thermal energy storage logic and of the solar field freeze protection system, but follow standard schemes. ASSALT, Ase Software for SALT csp plants, has been developed to improve MSPT plant's simulations, by exploiting the most correct operational strategies in order to provide more accurate technical and economical results. In particular, ASSALT applies MSPT specific control logics for the electric energy production and delivery strategy as well as the operation modes of the Solar Field in off-normal sunshine condition. With this approach, the estimated plant efficiency is increased and the electricity consumptions required for the plant operation and management is drastically reduced. Here we present a first comparative study on a real case 55 MWe Molten Salt Parabolic Trough CSP plant placed in the Tibetan highlands, using ASSALT and SAM (System Advisor Model), which is a commercially available simulation tool.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mendelsohn, M.; Lowder, T.; Canavan, B.
Over the last several years, solar energy technologies have been, or are in the process of being, deployed at unprecedented levels. A critical recent development, resulting from the massive scale of projects in progress or recently completed, is having the power sold directly to electric utilities. Such 'utility-scale' systems offer the opportunity to deploy solar technologies far faster than the traditional 'behind-the-meter' projects designed to offset retail load. Moreover, these systems have employed significant economies of scale during construction and operation, attracting financial capital, which in turn can reduce the delivered cost of power. This report is a summary ofmore » the current U.S. utility-scale solar state-of-the-market and development pipeline. Utility-scale solar energy systems are generally categorized as one of two basic designs: concentrating solar power (CSP) and photovoltaic (PV). CSP systems can be further delineated into four commercially available technologies: parabolic trough, central receiver (CR), parabolic dish, and linear Fresnel reflector. CSP systems can also be categorized as hybrid, which combine a solar-based system (generally parabolic trough, CR, or linear Fresnel) and a fossil fuel energy system to produce electric power or steam.« less
Concentrating Solar Power Projects - Extresol-2 | Concentrating Solar Power
Sesmero (Badajoz) Owner(s): ACS/Cobra Group (100%) Technology: Parabolic trough Turbine Capacity: Net : 158,000 MWh/yr (Expected/Planned) Contact(s): Manuel Cortes; Ana Salazar Company: ACS/Cobra Group Break Project Type: Commercial Participants Developer(s): ACS/Cobra Group Owner(s) (%): ACS/Cobra Group (100
Concentrating Solar Power Projects - Extresol-3 | Concentrating Solar Power
Sesmero (Badajoz) Owner(s): ACS/Cobra Group (100%) Technology: Parabolic trough Turbine Capacity: Net : 158,000 MWh/yr (Expected/Planned) Contact(s): Manuel Cortes; Ana Salazar Company: ACS/Cobra Group Break years Project Type: Commercial Participants Developer(s): ACS/Cobra Group Owner(s) (%): ACS/Cobra Group
Concentrating Solar Power Projects - Manchasol-2 | Concentrating Solar
Juan (Ciudad Real) Owner(s): ACS/Cobra Group (100%) Technology: Parabolic trough Turbine Capacity: Net : ACS/Cobra Group Break Ground: May 2009 Start Production: April 2011 Construction Job-Years: 600 Annual : Commercial Participants Developer(s): ACS/Cobra Group Owner(s) (%): ACS/Cobra Group (100%) EPC Contractor
Concentrating Solar Power Projects - Manchasol-1 | Concentrating Solar
Juan (Ciudad Real) Owner(s): ACS/Cobra Group (100%) Technology: Parabolic trough Turbine Capacity: Net : ACS/Cobra Group Break Ground: October 2008 Start Production: January 2011 Construction Job-Years: 600 : Commercial Participants Developer(s): ACS/Cobra Group Owner(s) (%): ACS/Cobra Group (100%) EPC Contractor
NASA Astrophysics Data System (ADS)
Muhlen, Luis S. W.; Najafi, Behzad; Rinaldi, Fabio; Marchesi, Renzo
2014-04-01
Solar troughs are amongst the most commonly used technologies for collecting solar thermal energy and any attempt to increase the performance of these systems is welcomed. In the present study a parabolic solar trough is simulated using a one dimensional finite element model in which the energy balances for the fluid, the absorber and the envelope in each element are performed. The developed model is then validated using the available experimental data . A sensitivity analysis is performed in the next step in order to study the effect of changing the type of the working fluid and the corresponding Reynolds number on the overall performance of the system. The potential improvement due to the addition of a shield on the upper half of the annulus and enhancing the convection coefficient of the heat transfer fluid is also studied.
NASA Astrophysics Data System (ADS)
Hato, M.; Inamori, T.; Matsuoka, T.; Shimizu, S.
2003-04-01
Occurrence of methane hydrates in the Nankai Trough, located off the south-eastern coast of Japan, was confirmed by the exploratory test well drilling conducted by Japan’s Ministry of International Trade and Industry in 1999. Confirmation of methane hydrate has given so big impact to the Japan's future energy strategy and scientific and technological interest was derived from the information of the coring and logging results at the well. Following the above results, Japan National Oil Corporation (JNOC) launched the national project, named as MH21, for establishing the technology of methane hydrate exploration and related technologies such as production and development. As one of the research project for evaluating the total amount of the methane hydrate, Amplitude versus Offset (AVO) was applied to the seismic data acquired in the Nankai Trough area. The main purpose of the AVO application is to evaluate the validity of delineation of methane hydrate-bearing zones. Since methane hydrate is thought to accompany with free-gas in general just below the methane hydrate-bearing zones, the AVO has a possibility of describing the presence of free-gas. The free-gas is thought to be located just below the base of methane hydrate stability zone which is characterized by the Bottom Simulating Reflectors (BSRs) on the seismic section. In this sense, AVO technology, which was developed as gas delineation tools, can be utilized for methane hydrate exploration. The result of AVO analysis clearly shows gas-related anomaly below the BSRs. Appearance of the AVO anomaly has so wide variety. Some of the anomalies might not correspond to the free-gas existence, however, some of them may show free-gas. We are now going to develop methodology to clearly discriminate free-gas from non-gas zone by integrating various types of seismic methods such as seismic inversion and seismic attribute analysis.
Proceedings of the First Semiannual Distributed Receiver Program Review
NASA Technical Reports Server (NTRS)
1980-01-01
Point focus and line focus distributed receiver solar thermal technology for the production of electric power and of industrial process heat is addressed. Concentrator, receiver, and power conversion development are covered along with hardware tests and evaluation. Mass production costing, parabolic dish applications, and trough and bowl systems are included.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schuett, K.J.; Pawlak, J.P.; Traina, L.
No. 13 Blast Furnace at US Steel`s Gary Works is a 35 tuyere furnace with a 36.5 ft. hearth capable of producing over 9,000 tons of hot metal per day. The current casthouse design was placed in service following the second reline in the fall of 1979. This design anticipated daily production rates averaging 7,500 tons of hot metal per day and provided for removable troughs at two of the three tapholes. At the time, the troughs were rammed with a high alumina/silicon carbide granular ramming material that provided the operators with trough campaign lives between 60,000--70,000 tons of hotmore » metal produced. As refractory technology progressed, low cement/low moisture castables were introduced to the trough systems on No. 13 Blast Furnace. The immediate success of the castables was tempered by emergence of a new unexpected problem. That problem was the thermal expansion of the castable. The paper describes the problems that resulted in the need to modify the trough design, the new design of the trough, and its improvement in iron trough campaign life and reliability.« less
Energy 101: Concentrating Solar Power
None
2018-02-07
From towers to dishes to linear mirrors to troughs, concentrating solar power (CSP) technologies reflect and collect solar heat to generate electricity. A single CSP plant can generate enough power for about 90,000 homes. This video explains what CSP is, how it works, and how systems like parabolic troughs produce renewable power. For more information on the Office of Energy Efficiency and Renewable Energy's CSP research, see the Solar Energy Technology Program's Concentrating Solar Power Web page at http://www1.eere.energy.gov/solar/csp_program.html.
OUT Success Stories: Solar Hot Water Technology
DOE R&D Accomplishments Database
Clyne, R.
2000-08-01
Solar hot water technology was made great strides in the past two decades. Every home, commercial building, and industrial facility requires hot water. DOE has helped to develop reliable and durable solar hot water systems. For industrial applications, the growth potential lies in large-scale systems, using flat-plate and trough-type collectors. Flat-plate collectors are commonly used in residential hot water systems and can be integrated into the architectural design of the building.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Grogan, Dylan C. P.
2013-08-15
Executive Summary This Final Report for the "Development of Molten-Salt Heat Transfer Fluid (HTF) Technology for Parabolic Trough Solar Power Plants” describes the overall project accomplishments, results and conclusions. Phase 1 analyzed the feasibility, cost and performance of a parabolic trough solar power plant with a molten salt heat transfer fluid (HTF); researched and/or developed feasible component options, detailed cost estimates and workable operating procedures; and developed hourly performance models. As a result, a molten salt plant with 6 hours of storage was shown to reduce Thermal Energy Storage (TES) cost by 43.2%, solar field cost by 14.8%, and levelizedmore » cost of energy (LCOE) by 9.8% - 14.5% relative to a similar state-of-the-art baseline plant. The LCOE savings range met the project’s Go/No Go criteria of 10% LCOE reduction. Another primary focus of Phase 1 and 2 was risk mitigation. The large risk areas associated with a molten salt parabolic trough plant were addressed in both Phases, such as; HTF freeze prevention and recovery, collector components and piping connections, and complex component interactions. Phase 2 analyzed in more detail the technical and economic feasibility of a 140 MWe,gross molten-salt CSP plant with 6 hours of TES. Phase 2 accomplishments included developing technical solutions to the above mentioned risk areas, such as freeze protection/recovery, corrosion effects of applicable molten salts, collector design improvements for molten salt, and developing plant operating strategies for maximized plant performance and freeze risk mitigation. Phase 2 accomplishments also included developing and thoroughly analyzing a molten salt, Parabolic Trough power plant performance model, in order to achieve the project cost and performance targets. The plant performance model and an extensive basic Engineering, Procurement, and Construction (EPC) quote were used to calculate a real levelized cost of energy (LCOE) of 11.50¢/kWhe , which achieved the Phase 2 Go/No Go target of less than 0.12¢/kWhe. Abengoa Solar has high confidence that the primary risk areas have been addressed in the project and a commercial plant utilizing molten salt is economically and technically feasible. The strong results from the Phase 1 and 2 research, testing, and analyses, summarized in this report, led Abengoa Solar to recommend that the project proceed to Phase 3. However, a commercially viable collector interconnection was not fully validated by the end of Phase 2, combined with the uncertainty in the federal budget, forced the DOE and Abengoa Solar to close the project. Thus the resources required to construct and operate a molten salt pilot plant will be solely supplied by Abengoa Solar.« less
Optical and mechanical tolerances in hybrid concentrated thermal-PV solar trough.
Diaz, Liliana Ruiz; Cocilovo, Byron; Miles, Alexander; Pan, Wei; Blanche, Pierre-Alexandre; Norwood, Robert A
2018-05-14
Hybrid thermal-PV solar trough collectors combine concentrated photovoltaics and concentrated solar power technology to harvest and store solar energy. In this work, the optical and mechanical requirements for optimal efficiency are analyzed using non-sequential ray tracing techniques. The results are used to generate opto-mechanical tolerances that can be compared to those of traditional solar collectors. We also explore ideas on how to relieve tracking tolerances for single-axis solar collectors. The objective is to establish a basis for tolerances required for the fabrication and manufacturing of hybrid solar trough collectors.
NASA Astrophysics Data System (ADS)
Kaneda, Y.; Kawaguchi, K.; Araki, E.; Matsumoto, H.; Nakamura, T.; Nakano, M.; Kamiya, S.; Ariyoshi, K.; Baba, T.; Ohori, M.; Hori, T.; Takahashi, N.; Kaneko, S.; Donet Research; Development Group
2010-12-01
Yoshiyuki Kaneda Katsuyoshi Kawaguchi*, Eiichiro Araki*, Shou Kaneko*, Hiroyuki Matsumoto*, Takeshi Nakamura*, Masaru Nakano*, Shinichirou Kamiya*, Keisuke Ariyoshi*, Toshitaka Baba*, Michihiro Ohori*, Narumi Takakahashi*, and Takane Hori** * Earthquake and Tsunami Research Project for Disaster Prevention, Leading Project , Japan Agency for Marine-Earth Science and Technology (JAMSTEC) **Institute for Research on Earth Evolution, Japan Agency for Marine-Earth Science and Technology (JAMSTEC) DONET (Dense Ocean Floor Network for Earthquakes and Tsunamis) is the real time monitoring system of the Tonankai seismogenic zones around the Nankai trough southwestern Japan. We were starting to develop DONET to perform real time monitoring of crustal activities over there and the advanced early warning system. DONET will provide important and useful data to understand the Nankai trough maga thrust earthquake seismogenic zones and to improve the accuracy of the earthquake recurrence cycle simulation. Details of DONET concept are as follows. 1) Redundancy, Extendable function and advanced maintenance system using the looped cable system, junction boxes and the ROV/AUV. DONET has 20 observatories and incorporated in a double land stations concept. Also, we are developed ROV for the 10km cable extensions and heavy weight operations. 2) Multi kinds of sensors to observe broad band phenomena such as long period tremors, very low frequency earthquakes and strong motions of mega thrust earthquakes over M8: Therefore, sensors such as a broadband seismometer, an accelerometer, a hydrophone, a precise pressure gauge, a differential pressure gauge and a thermometer are equipped with each observatory in DONET. 3) For speedy detections, evaluations and notifications of earthquakes and tsunamis: DONET system will be deployed around the Tonankai seismogenic zone. 4) Provide data of ocean floor crustal deformations derived from pressure sensors: Simultaneously, the development of data assimilation method using DONET data is very important to improve the recurrence cycle simulation model. 5) Understanding of the interaction between the crust and upper mantle around the Nankai trough subduction zone. We will deploy DONET not only in the Tonankai seismogenic zone but also DONET2 with high voltages in the Nankai seismogenic zone western the Nankai trough: The total system will be deployed to understand the seismic linkage between the Tonankai and Nankai earthquakes: Using DONET and DONET2 data, we will be able to observe the crustal activities and before and after slips at the Tonankai earthquake and Nankai earthquake. And we will improve the recurrence cycle simulation model by the advanced data assimilation method. Actually, we constructed one observatory in DONET and observed some earthquakes and tsunamis. We will introduce details of DONET/DONET2 and some observed data.
Numerical Optimization Using Desktop Computers
1980-09-11
concentrating compound parabolic trough solar collector . Thermophysical, geophysical, optical and economic analyses were used to compute a life-cycle...third computer program, NISCO, was developed to model a nonimaging concentrating compound parabolic trough solar collector using thermophysical...concentrating compound parabolic trough Solar Collector . C. OBJECTIVE The objective of this thesis was to develop a system of interactive programs for the Hewlett
Parabolic Trough Collector Cost Update for the System Advisor Model (SAM)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kurup, Parthiv; Turchi, Craig S.
2015-11-01
This report updates the baseline cost for parabolic trough solar fields in the United States within NREL's System Advisor Model (SAM). SAM, available at no cost at https://sam.nrel.gov/, is a performance and financial model designed to facilitate decision making for people involved in the renewable energy industry. SAM is the primary tool used by NREL and the U.S. Department of Energy (DOE) for estimating the performance and cost of concentrating solar power (CSP) technologies and projects. The study performed a bottom-up build and cost estimate for two state-of-the-art parabolic trough designs -- the SkyTrough and the Ultimate Trough. The SkyTroughmore » analysis estimated the potential installed cost for a solar field of 1500 SCAs as $170/m 2 +/- $6/m 2. The investigation found that SkyTrough installed costs were sensitive to factors such as raw aluminum alloy cost and production volume. For example, in the case of the SkyTrough, the installed cost would rise to nearly $210/m 2 if the aluminum alloy cost was $1.70/lb instead of $1.03/lb. Accordingly, one must be aware of fluctuations in the relevant commodities markets to track system cost over time. The estimated installed cost for the Ultimate Trough was only slightly higher at $178/m 2, which includes an assembly facility of $11.6 million amortized over the required production volume. Considering the size and overall cost of a 700 SCA Ultimate Trough solar field, two parallel production lines in a fully covered assembly facility, each with the specific torque box, module and mirror jigs, would be justified for a full CSP plant.« less
NASA Astrophysics Data System (ADS)
Broughton, Paul L.
2013-01-01
The sub-Cretaceous paleotopography underlying giant Lower Cretaceous Athabasca oil sands, northern Alberta, has an orthogonal lattice pattern of troughs up to 50 km long and 100 m deep between pairs of cross-cutting lineaments. These structures are interpreted to have been inherited from a similar pattern of dissolution collapse-subsidence troughs in the underlying Middle Devonian salt beds. Removal of more than 100 m of halite salt fragmented the overlying Upper Devonian strata into fault blocks and collapse breccias that subsided into the underlying dissolution troughs. The unusually low 1:2 to 1:3 thickness ratios of halite salts to the overlying strata resulted in the Upper Devonian strata collapse-subsidence into underlying salt dissolution troughs being more cataclysmic during the first phase of salt removal. The second phase of slower but complete salt removal between the earlier troughs resulted in a more gradual subsidence of the overlying strata. This obliterated the earlier pattern of giant cross-cutting dissolution troughs bounded by major lineaments. The collapse breccia fabrics underlying the earlier troughs differ from those from areas between the troughs. Collapse breccias underlying the large troughs often have crushed fabrics distributed in zones that rapidly pinched out between fault blocks. Breccias between troughs developed as giant mosaics of detached carbonate blocks that formed breccia pipe complexes. Multiple sinkholes up to 100 m deep aligned along multi-km linear valley trends that dissected the sub-Cretaceous paleotopography. These sinkhole trends formed orthogonal patterns inherited from underlying lattice of NW-SE and NE-SW salt structured lineaments. These cross-cutting sinkhole trends have a smaller 5 km scale reticulate pattern similar to the giant 50 km scale pattern of collapse-subsidence troughs. Other sinkholes developed as lower McMurray strata sagged when underlying Devonian fault blocks and breccia pipes differentially subsided.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kurup, Parthiv; Turchi, Craig
2015-11-01
After significant interest in the 1970s, but relatively few deployments, the use of solar technologies for thermal applications, including enhanced oil recovery (EOR), desalination, and industrial process heat (IPH), is again receiving global interest. In particular, the European Union (EU) has been a leader in the use, development, deployment, and tracking of Solar Industrial Process Heat (SIPH) plants. The objective of this study is to ascertain U.S. market potential of IPH for concentrating collector technologies that have been developed and promoted through the U.S. Department of Energy's Concentrating Solar Power (CSP) Program. For this study, the solar-thermal collector technologies ofmore » interest are parabolic trough collectors (PTCs) and linear Fresnel (LF) systems.« less
Harmonization of standards for parabolic trough collector testing in solar thermal power plants
NASA Astrophysics Data System (ADS)
Sallaberry, Fabienne; Valenzuela, Loreto; Palacin, Luis G.; Leon, Javier; Fischer, Stephan; Bohren, Andreas
2017-06-01
The technology of parabolic trough collectors (PTC) is used widely in concentrating Solar Power (CSP) plants worldwide. However this type of large-size collectors cannot be officially tested by an accredited laboratory and certified by an accredited certification body so far, as there is no standard adapted to its particularity, and the current published standard for solar thermal collectors are not completely applicable to them. Recently some standardization committees have been working on this technology. This paper aims to give a summary of the standardized testing methodology of large-size PTC for CSP plants, giving the physical model chosen for modeling the thermal performance of the collector in the new revision of standard ISO 9806 and the points still to be improved in the standard draft IEC 62862-3-2. In this paper, a summary of the testing validation performed on one parabolic trough collector installed in one of the test facilities at the Plataforma Solar de Almería (PSA) with this new model is also presented.
Aeolian sand transport over complex intertidal bar-trough beach topography
NASA Astrophysics Data System (ADS)
Anthony, Edward J.; Ruz, Marie-Hélène; Vanhée, Stéphane
2009-04-01
Aeolian sand transport on macrotidal beaches with complex intertidal bar-trough topography (ridge-and-runnel beaches) was assessed from experiments in northern France that involved measurements of wind speed, saltation, surface moisture contents, and rates of sand trapping across surveyed portions of the upper beach profile. Beaches exhibiting intertidal bars and troughs are much more complex, topographically, than simple reflective or dissipative beaches. Furthermore, the intertidal bar-trough morphology commonly exhibits strong cross-shore variations in the moisture contents of the beach surface and in patterns of bedform development. The results of four 30-minute experiments, conducted along topographically surveyed portions of the upper beach-dune toe profile, show that troughs act as extremely efficient sand interceptors, because of their permanently saturated state, which also inhibits sand mobilisation. Troughs, thus, limit or segment the dry fetch during conditions of intermittent saltation. Flow lines, inferred from the wind profiles, suggest that complex interactions at the boundary layer are generated by the bar-trough topography. Troughs systematically appear to be characterised by air expansion, while bar faces generate ramp wind acceleration for onshore winds, and sometimes immediate downwind deceleration for offshore winds. These effects may also contribute to cross-shore variations in the rates of sand trapping. Finally, a simple conceptual model of effective fetch development, integrating the effects of the spring-neap tidal range and of gross bar-trough morphological variability over time, is proposed for bar-trough beaches. The model highlights the key theme of fetch segmentation induced by cross-shore differentiation in the moisture contents of the beach surface hinged on the complex topography of multiple bars and troughs.
Technical Manual for the SAM Physical Trough Model
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wagner, M. J.; Gilman, P.
2011-06-01
NREL, in conjunction with Sandia National Lab and the U.S Department of Energy, developed the System Advisor Model (SAM) analysis tool for renewable energy system performance and economic analysis. This paper documents the technical background and engineering formulation for one of SAM's two parabolic trough system models in SAM. The Physical Trough model calculates performance relationships based on physical first principles where possible, allowing the modeler to predict electricity production for a wider range of component geometries than is possible in the Empirical Trough model. This document describes the major parabolic trough plant subsystems in detail including the solar field,more » power block, thermal storage, piping, auxiliary heating, and control systems. This model makes use of both existing subsystem performance modeling approaches, and new approaches developed specifically for SAM.« less
Solar thermal technology evaluation, fiscal year 1982. Volume 1: Executive summary
NASA Technical Reports Server (NTRS)
1983-01-01
Three primary solar concepts the central receiver, parabolic dish, and parabolic trough are investigated. To a lesser extent, the hemispherical bowl and salt-gradient solar pond are also being studied. Each technology is described.
Solar Energy Development on DoD Installations in the Mojave & Colorado Deserts
2011-11-30
roof mount • Acreage: – ~6.2 million acres on 9 installations – 250,000 acres with some level of suitability for solar – 120,000 acres are estimated...technologies: thin - film and crystalline PV x fixed and single-axis tracking; trough; dish/Stirling engine. • 2 ownership structures (MILCON and 3rd party...1icfi.com | Solar Energy Development on DoD Installations in the Mojave & Colorado Deserts Bob Kwartin ICF International November 30, 2011 Report
NASA Astrophysics Data System (ADS)
Ramohalli, K.
1981-05-01
The solar thermal fuels and chemicals program at Jet Propulsion Laboratory are described. High technology is developed and applied to displace fossil fuel (oil) use in the production/processing of valuable fuels and chemicals. The technical and economic feasibility is demonstrated to extent that enables the industry to participate and commercialize the product. A representative process, namely Furfural production with a bottoming of acetone, butanol and ethanol, is described. Experimental data from all solar production of furfural is discussed. Estimates are given to show the attractiveness of this process, considering its flexibility to be adaptable to dishes, troughs or central receivers. Peat, lignite and low rank coal processing, heavy oil stripping and innovative technologies for process diagnostics and control are mentioned as examples of current projects under intensive development.
NASA Technical Reports Server (NTRS)
Ramohalli, K.
1981-01-01
The solar thermal fuels and chemicals program at Jet Propulsion Laboratory are described. High technology is developed and applied to displace fossil fuel (oil) use in the production/processing of valuable fuels and chemicals. The technical and economic feasibility is demonstrated to extent that enables the industry to participate and commercialize the product. A representative process, namely Furfural production with a bottoming of acetone, butanol and ethanol, is described. Experimental data from all solar production of furfural is discussed. Estimates are given to show the attractiveness of this process, considering its flexibility to be adaptable to dishes, troughs or central receivers. Peat, lignite and low rank coal processing, heavy oil stripping and innovative technologies for process diagnostics and control are mentioned as examples of current projects under intensive development.
Concentrating Solar Power Projects - DEWA CSP Trough Project |
: Parabolic trough Turbine Capacity: Net: 600.0 MW Gross: 600.0 MW Status: Under development Start Year: 2020 Ground: 2018 Start Production: 2020 PPA/Tariff Rate: 7.3 US cents per kWh Participants Developer(s): ACWA
GPS/acoustic Seafloor Geodetic Observations Near the Nankai Trough Axis
NASA Astrophysics Data System (ADS)
Tadokoro, K.; Yasuda, K.; Fujii, C.; Watanabe, T.; Nagai, S.
2013-12-01
The GPS/acoustic seafloor geodetic observation system, which uses precise acoustic ranging and kinematic GPS positioning techniques, has been developed as a useful tool for observing seafloor crustal deformations associated with plate convergence and with earthquakes that occurred in ocean area including the 2011 Tohoku-oki Earthquake of Mw 9.0. Our research group installed eight seafloor benchmarks for this observation system in source areas of anticipated major interplate earthquakes along the Nankai Trough, off southwestern Japan. We have performed campaign measurement for 4-8 years until the end of 2012. The error of displacement rate is almost 5 mm/y through the monitoring for more than four years. At the northern-most potion of the Nankai (Suruga) Trough, the observed steady horizontal displacement rate is 45 mm/y toward west. Also no significant velocity difference is observed across the trough, indicating strong interplate locking up to the shallowest segments. On the other hand, site velocities are 40 mm/y in the direction of N75W at the central region of the Nankai trough, 70-90 km landward from the trough axis. Although this result is the strong evidence for interplate locking, with coupling ratios of 60-80% on the basis of the back-slip model, it has no resolution for the interplate locking at the most-shallowest segments whose depths are 0-10 km. In other words, seaward up-dip limit of locked zone is never resolved from the present seafloor benchmark network [Tadokoro et al., 2012] . Large co-seismic slips larger than 40-50 m on the shallowest interplate segment [Ito et al., 2011; Fujii et al., 2011; Iinuma et al., 2012] are the cause of the unexpected high tsunami that has attacked the pacific coasts of the Tohoku region during the Tohoku-oki Earthquake; it is, therefore, essential to understand slip deficit or strain accumulation condition near the trench axis, also for the anticipated mega-thrust earthquake at the Nankai Trough. For this reason, we installed a new seafloor benchmark in the vicinity of the Nankai Trough axis, about 15 km landward from the trough axis, on July 16, 2013. In addition, we plan to install another new benchmark on the other side of the Nankai Trough in August of this year, to directly measure the motion of the subducting Philippine Sea Plate. The coupling ratio is calculated from slip deficit divided by convergence rate. We can directly 'measure' the coupling ratio from crustal deformation at the newly-installed station on the Philippine Sea Plate, without using global plate motion models. Acknowledgments: We are grateful to the captain and crews of R/V "Asama" of Mie Prefecture Fisheries Research Institute, Japan. This study has been partly promoted by Ministry of Education, Culture, Sports, Science and Technology, Japanese Government.
A V-band wafer probe using ridge-trough waveguide
NASA Astrophysics Data System (ADS)
Godshalk, Edward M.
1991-12-01
A V-band (50-75 GHz) wafer probe is presented. The probe features a type of waveguide developed to allow transition from rectangular waveguide to coplanar waveguide. The waveguide consists of a ridge extending from the upper waveguide wall into a trough in the lower waveguide wall, and is known as the ridge-trough waveguide. A mathematical model is presented that allows important properties of the ridge-trough waveguide, such as the cutoff frequency and characteristic impedance, to be calculated.
Improved Large Aperture Collector Manufacturing
DOE Office of Scientific and Technical Information (OSTI.GOV)
O'Rourke, Deven; Farr, Adrian
2015-12-01
The parabolic trough is the most established CSP technology and carries a long history of design experimentation dating back to the 1970’s. This has led to relatively standardized collector architectures, a maturing global supply chain, and a fairly uniform cost reduction strategy. Abengoa has deployed more than 1,500MWe of CSP troughs across several countries and has built and tested full-scale prototypes of many R&D concepts. The latest trough R&D efforts involved efforts to internalize non-CSP industry experience including a preliminary DFMA principles review done with Boothroyd Dewhurst, a construction literature review by the Arizona State University School of Construction Management,more » and two more focused manufacturing engineering subcontracts done by Ricardo Inc. and the nonprofit Edison Welding Institute. The first two studies highlighted strong opportunities in lowering part count, standardizing components and fasteners, developing modular designs to support prefabrication and automation, and devising simple, error-proof manual assembly methods. These principles have delivered major new cost savings in otherwise “mature” products in analogous industries like automotive, truck trailer manufacture, metal building fabrication, and shipbuilding. For this reason, they were core in the design development of the SpaceTube® collector, and arguably key to its early successes. The latter two studies were applied specifically to the first-generation SpaceTube® design and were important in setting the direction of the present SolarMat project. These studies developed a methodology to analyze the costs of manufacture and assembly, and identify new tooling concepts for more efficient manufacture. Among the main opportunities identified in these studies were the automated mirror arm manufacturing concept and the need for a less infrastructure-intensive assembly line, both of which now form central pillars of the SolarMat project strategy. These new designs will be supported by new technology in the area of quality control inspection, in which state of the art photogrammetry and laser CMM inspection methods will be used to qualify parts and assemblies, and in which the recently-developed Absorber Reflection Method will enable in-line quality control inspection of modules produced by the new high-rate production line.« less
1975-05-01
Extensive deposits of low-grade ore ( taconite ) remain in the county, and redevelopment of mining in Iron County is a possibility, utilizing modern technology...shale-derived sediments at the advent of the continental glaciation. The resistant sides of the trough (the present Minnesota shore, the Keweenaw...glacier retreated, a high terminal moraine associated with high ground on the Minnesota and Hichigan sides allowed a glacial lake to develop. The
Hale, Cory M; Seabury, Robert W; Steele, Jeffrey M; Darko, William; Miller, Christopher D
2017-06-01
To determine whether there is an association between higher vancomycin trough concentrations and attainment of a calculated area under the concentration-time curve (AUC)/minimum inhibitory concentration (MIC) ≥400. A retrospective analysis was conducted among vancomycin-treated adult patients with a positive methicillin-resistant Staphylococcus aureus (MRSA) culture. Attainment of a calculated AUC/MIC ≥400 was compared between patients with troughs in the reference range of 15 to 20 mg/L and those with troughs in the following ranges: <10, 10 to 14.9, and >20 mg/L. Nephrotoxicity was assessed as a secondary outcome based on corrected average vancomycin troughs over 10 days of treatment. Overall, 226 patients were reviewed and 100 included. Relative to troughs ≥10, patients with vancomycin troughs <10 mg/L were 73% less likely to attain an AUC/MIC ≥400 (odds ratio [OR] 0.27, 95% confidence interval [CI]: 0.01-0.75). No difference was found in the attainment of an AUC/MIC ≥400 in patients with troughs of 10 to 14.9 mg/L and >20 mg/L when compared to patients with troughs of 15 to 20 mg/L. The mean corrected average vancomycin trough was higher in patients developing nephrotoxicity compared to those who did not (19.5 vs 14.5 mg/L, P < .001). Achieving vancomycin serum trough concentrations of 15 to 20 mg/L did not result in an increased attainment of the AUC/MIC target relative to troughs of 10 to 14.9 mg/L but may increase nephrotoxicity risk.
Benefits of full scope simulators during solar thermal power plants design and construction
NASA Astrophysics Data System (ADS)
Gallego, José F.; Gil, Elena; Rey, Pablo
2017-06-01
In order to efficiently develop high-precision dynamic simulators for solar thermal power plants, Tecnatom adapted its simulation technology to consider solar thermal models. This effort and the excellent response of the simulation market have allowed Tecnatom to develop simulators with both parabolic trough and solar power tower technologies, including molten salt energy storage. These simulators may pursue different objectives, giving rise to training or engineering simulators. Solar thermal power market combines the need for the training of the operators with the potential benefits associated to the improvement of the design of the plants. This fact along with the simulation capabilities enabled by the current technology and the broad experience of Tecnatom present the development of an engineering+training simulator as a very advantageous option. This paper describes the challenge of the development and integration of a full scope simulator during the design and construction stages of a solar thermal power plant, showing the added value to the different engineering areas.
The Ordovician Sebree Trough: An oceanic passage to the Midcontinent United States
Kolata, Dennis R.; Huff, W.D.; Bergstrom, Stig M.
2001-01-01
The Sebree Trough is a relatively narrow, shale-filled sedimentary feature extending for several hundred kilometers across the Middle and Late Ordovician carbonate platform of the Midcontinent United States. The dark graptolitic shales within the trough stand in contrast to the coeval bryozoan-brachiopod-echinodermrich limestones on the flanking platforms. We infer from regional stratal patterns, thickness and facies trends, and temporal relations established by biostratigraphy and K-bentonite stratigraphy that the Sebree Trough initially began to develop during late Turinian to early Chatfieldian time (Mohawkian Series) as a linear bathymetric depression situated over the failed late Precambrian-Early Cambrian Reelfoot Rift. Rising sea level and positioning of a subtropical convergence zone along the southern margin of Laurentia caused the rift depression to descend into cool, oxygen-poor, phosphate-rich oceanic waters that entered the southern reaches of the rift from the Iapetus Ocean. The trough apparently formed in a system of epicontinental estuarine circulation marked by a density-stratified water column. Trough formation was accompanied by cessation of carbonate sedimentation, deposition of graptolitic shales, development of hardground omission surfaces, substrate erosion, and local phosphogenesis. The carbonate platforms on either side of the trough are dominated by bryozoan-brachiopod-echinoderm grainstones and packstones that were deposited in zones of mixing where cool, nutrient-rich waters encountered warmer shelf waters. Concurrently, lime mudstone and wackestone were deposited shoreward (northern Illinois, Wisconsin, Iowa, Minnesota, Michigan) in warmer, more tropical shallow seas. Coeval upward growth of the flanking carbonate platforms sustained and enhanced development of the trough shale facies. Five widespread diachronous late Mohawkian and Cincinnatian omission surfaces are present in the carbonate facies of the Midcontinent. These surfaces include sub-Deicke K-bentonite, DSI; top of Black River Limestone, DS2; base and top of the Guttenberg Limestone Member of the Decorah Formation, DS3 and DS4; and top of the Trenton Limestone, DS5. Some of the surfaces correspond to previously described depositional sequence boundaries. All five surfaces, which embody deepening phases on top of high-stand-systems tracts, converge in the Sebree Trough, indicating that the trough was a long-lived feature and was the source of eutrophic waters that episodically spread across the adjacent platforms, terminating carbonate production. Late Turinian and early Chatfieldian incipient drowning episodes were followed by a final drowning event that began in the Sebree Trough during the late Chatfieldian (Climacograptus spiniferus Zone) and reached southernmost Minnesota and other regions far within the platform interior by Richmondian time (Amorphognathus ordovicicus Zone).
Digital Literacy Development of Students Involved in an ICT Educational Project
NASA Astrophysics Data System (ADS)
Quintana, Maria Graciela Badilla; Pujol, Meritxell Cortada
The impact of the Information and Communication Technologies (ICT) has become the core of a change that involves most of the society fields, consequently the technological and informational literacy are essential requirements in education. The research is a quasi-experimental and ex-post-facto study in schools from Spain. The aim was to describe and analyze the involvement showed by 219 students who participated in a development of ICT's Project named Ponte dos Brozos. The research objective was to respond if the students who usually worked with ICT, had better knowledge and management with computing tools, and if they are better prepared in researching and selecting information. Results showed that students who have a higher contact with ICTs know about the technology and how to use it, also better knowledge and control of the computer and operative systems, a high information management level trough the Internet, although their literacy in information is devoid.
Concentrating Solar Power Projects - Holaniku at Keahole Point |
: Currently Non-Operational Start Year: 2009 Do you have more information, corrections, or comments ? Background Technology: Parabolic trough Status: Currently Non-Operational Country: United States City
Characterization of inappetent sheep in a feedlot using radio-tracking technology.
Barnes, Anne L; Wickham, Sarah L; Admiraal, Ryan; Miller, David W; Collins, Teresa; Stockman, Catherine; Fleming, Patricia A
2018-04-03
The feeding and drinking behaviours of sheep were monitored using RFID technology at a commercial pre-embarkation feedlot in Western Australia with the aim of characterizing feeding and drinking patterns of inappetent sheep that might allow them to be treated. Feeding and drinking behaviours of sheep were compared with their survival and change in body condition. Patterns of number of visits and the time spent at feed and water troughs were analyzed for a total of 8,206 sheep, representing four consignments that were monitored for a range of 6-31 d. Data for feeding and drinking behaviours were compared for the first 6 d. For animals that were alive at exit, 18.9% of sheep attended the feed trough for less than 0.25 h d-1 (15 min per day) on day 1; this decreased to only 2.4% of sheep by day 6. Of the sheep monitored, 0.93% died (n = 76); Salmonella spp. infection was the leading cause of death (n = 40; 52.6% of all deaths) across all months and was accompanied with inanition. There was marked variability in the average time spent at the feed trough for sheep that died eventually from salmonella/inanition (contributing to the lack of statistical difference in time spent at feed trough between sheep dying from different causes; P = 0.056). Over half (55%) of the animals diagnosed with salmonella/inanition spent an average of less than 0.50 h d-1 (30 min per day) and 45% less than 0.25 h d-1 at the feed trough. There was a negative correlation (r) in time spent at the feed trough overtime for individual sheep that died from salmonella/inanition, indicating that these individuals went off their feed. This pattern was not evident for animals that died from other causes (significant difference in r values between five categories of cause of death; P = 0.040). Characterization of feeding behaviour of sheep that died from salmonella/inanition therefore appears to require more than simply monitoring daily intake. There was no difference in time spent at water troughs between sheep that died or were alive at exit (average 0.30 ± 0.23 h d-1). This study reveals that the patterns of feeding and drinking behaviours during pre-embarkation feedlotting do not readily allow identification of animals that warrant singling out for veterinary care or alternative feed arrangements. This result highlights the need for experienced stockmanship in handling these animals.
Present-day erosion of Martian polar terrain by the seasonal CO2 jets
NASA Astrophysics Data System (ADS)
Portyankina, Ganna; Hansen, Candice J.; Aye, Klaus-Michael
2017-01-01
Here we report on the detection of new dendritic troughs created by the seasonal CO2 jet activity over several Martian years. According to Kieffers hypothesis (Kieffer, 2007) in Martian polar areas seasonal CO2 ice sublimation creates gas jets that deposit fans of mineral dust and sand on top of the CO2 ice. These jets and the related sub-ice gas flows are believed to carve troughs in the underlying polar deposits which, after multiple repetitions of this process throughout Martian spring seasons, create araneiform terrains. The High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter (MRO) detected the new troughs during its campaign for seasonal monitoring of the polar areas. The newly detected dendritic troughs are small shallow branching troughs (≈ 1.4 m wide) similar to the seasonal furrows previously detected in the northern hemisphere (Bourke, 2013). The essential difference between the new troughs and furrows lies in the fact that the troughs in the south are persistent while the northern furrows are erased each Martian year by the sand movement due to summer winds. From year to year the new southern troughs extend and develop new tributaries and their overall geometry turns from linear to dendritic, a characteristic shared with araneiform terrains. We believe that furrows have the same origin as the southern dendritic troughs but do not develop into dendritic shapes because of the high mobility of the dune material into which they are carved. Several locations where new dendritic troughs are observed lie in the vicinity of dunes. This gives us an observational indication that presence of erosive sand material is an important factor in creating (or at least starting) erosive processes that lead to the formation of dendritic troughs. By extrapolation the same mechanism should be acting to create the much larger araneiform terrains. Detection of the present day erosion working in polar areas and creating new topographical features is important for understanding of the processes that shape polar areas. Several years of HiRISE observations provide us with the information about the current rate of erosion and hence help estimate minimum ages of the araneiforms and the surface into which they are carved to be 1.3 × 103 Martian years.
NASA Technical Reports Server (NTRS)
2002-01-01
[figure removed for brevity, see original site] The style of erosion along the highlands-lowlands boundary of southern Elysium Planitia has produced a strange pattern of troughs that look like the skin of a reptile. In reality, a very clear process of landscape degradation is evident in this image. Some process has produced polygon-shaped troughs that create zones of weakness in the uppermost crust. It is likely that wind-blown particles deepen and widen the troughs, producing isolated knobs and mesas. Ultimately, the erosional reworking of the landscape is so complete that all signs of the upper layer are removed, leaving the smooth lowland surface to the north.Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.Simulation of hybrid solar power plants
NASA Astrophysics Data System (ADS)
Dieckmann, Simon; Dersch, Jürgen
2017-06-01
Hybrid solar power plants have the potential to combine advantages of two different technologies at the cost of increased complexity. The present paper shows the potential of the software greenius for the techno-economic evaluation of hybrid solar power plants and discusses two exemplary scenarios. Depreciated Concentrated Solar Power (CSP) plants based on trough technology can be retrofitted with solar towers in order to reach higher steam cycle temperatures and hence efficiencies. Compared to a newly built tower plant the hybridization of a depreciated trough plant causes about 30% lower LCOE reaching 104 /MWh. The second hybrid scenario combines cost-efficient photovoltaics with dispatchable CSP technology. This hybrid plant offers very high capacity factors up to 69% based on 100% load from 8am to 11pm. The LCOE of the hybrid plant are only slightly lower (174 vs. 186 /MWh) compared to the pure CSP plant because the capital expenditure for thermal storage and power block remains the same while the electricity output is much lower.
Concentrating Solar Power Projects - Urat Middle Banner 100MW Thermal Oil
Parabolic Trough project | Concentrating Solar Power | NREL Middle Banner 100MW Thermal Oil Thermal Oil Parabolic Trough project Country: China Location: Urat Middle Banner (Inner Mongolia) Owner(s , 2017 Start Production: 2018 Participants Developer(s): Changzhou Royal Tech Solar Thermal Equipment Co
Concentrating Solar Power Projects - Gulang 100MW Thermal Oil Parabolic
Trough project | Concentrating Solar Power | NREL Gulang 100MW Thermal Oil Parabolic Trough project Status Date: September 29, 2016 Project Overview Project Name: Gulang 100MW Thermal Oil Parabolic ): Webmaster Solar Participants Developer(s): Changzhou Royal Tech Solar Thermal Equipment Co., Ltd. Owner(s
NASA Technical Reports Server (NTRS)
Powell, John D.
2003-01-01
This document discusses the verification of the Secure Socket Layer (SSL) communication protocol as a demonstration of the Model Based Verification (MBV) portion of the verification instrument set being developed under the Reducing Software Security Risk (RSSR) Trough an Integrated Approach research initiative. Code Q of the National Aeronautics and Space Administration (NASA) funds this project. The NASA Goddard Independent Verification and Validation (IV&V) facility manages this research program at the NASA agency level and the Assurance Technology Program Office (ATPO) manages the research locally at the Jet Propulsion Laboratory (California institute of Technology) where the research is being carried out.
Hydrocarbon prospectivity assessment of the Southern Pattani Trough, Gulf of Thailand
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mountford, N.
The Pattani Trough is an elongate north to south basin in the Gulf of Thailand offshore area that developed from Oligocene times onward. Numerous hydrocarbon discoveries, mainly gas, have been made within the Tertiary stratigraphic section in areas adjacent to the depocenter of the basin, but only dry holes have been drilled on the extreme basin margins and flanking platform areas. The southern Pattani Trough represents a [open quotes]transition zone[close quotes] in terms of potential hydrocarbon prospectivity between the low potential/high exploration risk basin marginal areas, and the high potential/low exploration risk basin marginal area. The development of hydrocarbon accumulationmore » potential within the southern Pattani Trough can be related to a number of major controlling factors. These include structure, which on a regional scale shows a marked influence of tectonic regime on depositional system development, and on a more local scale determines trap development; stratigraphy, which determines reservoir geometry and potential hydrocarbon source rock facies distribution; petrology, which exerts a major control on depth related reservoir quality; overpressure development, which controls local migration pathways for generated hydrocarbons, and locally provides very efficient trap seals; geochemical factors, related to potential source facies distribution, hydrocarbon type; and thermal maturation of the section. The above factors have been combined to define low-, medium-, and high-risk exploration [open quotes]play fairways[close quotes] within the prospectivity transition zone of the southern Pattani Trough.« less
Concentrating Solar Power Projects - Solar Electric Generating Station VIII
: Harper Dry Lake, California (Mojave Desert) Owner(s): NextEra (50%) Technology: Parabolic trough Turbine City: Harper Dry Lake State: California County: San Bernardino Region: Mojave Desert Lat/Long Location
The Skaergaard trough layering: sedimentation in a convecting magma chamber
NASA Astrophysics Data System (ADS)
Vukmanovic, Z.; Holness, M. B.; Monks, K.; Andersen, J. C. Ø.
2018-05-01
The upper parts of the floor cumulates of the Skaergaard Intrusion, East Greenland, contain abundant features known as troughs. The troughs are gently plunging synformal structures comprising stacks of crescentic modally graded layers with a sharply defined mafic base that grades upward into plagioclase-rich material. The origin of the troughs and layering is contentious, attributed variously to deposition of mineral grains by magmatic currents descending from the nearby walls, or to in situ development by localised recrystallisation during gravitationally-driven compaction. They are characterised by outcrop-scale features such as mineral lineations parallel to the trough axis, evidence of erosion and layer truncation associated with migration of the trough axis, and disruption of layering by syn-magmatic slumping. A detailed microstructural study of the modal trough layers, using electron backscatter diffraction together with geochemical mapping, demonstrates that these rocks do not record evidence for deformation by either dislocation creep or dissolution-reprecipitation. Instead, the troughs are characterised by the alignment of euhedral plagioclase crystals with unmodified primary igneous compositional zoning. We argue that the lineations and foliations are, therefore, a consequence of grain alignment during magmatic flow. Post-accumulation amplification of the modal layering occurred as a result of differential migration of an unmixed immiscible interstitial liquid, with upwards migration of the Si-rich conjugate into the plagioclase-rich upper part of the layers, whereas the Fe-rich immiscible conjugate remained in the mafic base. Both field and microstructure evidence support the origin of the troughs as the sites of repeated deposition from crystal-rich currents descending from the nearby chamber walls.
Amin, Raid W; Guttmann, Rodney P; Harris, Quianna R; Thomas, Janesha W
2018-05-01
Vancomycin is a key antibiotic used in the treatment of multiple conditions including infections associated with cystic fibrosis and methicillin-resistant Staphylococcus aureus. The present study sought to develop a model based on empirical evidence of optimal vancomycin dose as judged by clinical observations that could accelerate the achievement of desired trough level in children with cystic fibrosis. Transformations of dose and trough were used to arrive at regression models with excellent fit for dose based on weight or age for a target trough. Results of this study indicate that the 2 proposed regression models are robust to changes in age or weight, suggesting that the daily dose on a per-kilogram basis is determined primarily by the desired trough level. The results show that to obtain a vancomycin trough level of 20 μg/mL, a dose of 80 mg/kg/day is needed. This analysis should improve the efficiency of vancomycin usage by reducing the number of titration steps, resulting in improved patient outcome and experience. © 2018, The American College of Clinical Pharmacology.
NASA Astrophysics Data System (ADS)
Guo, Kun; Zhai, Shikui; Yu, Zenghui; Wang, Shujie; Zhang, Xia; Wang, Xiaoyuan
2018-04-01
The Okinawa Trough is an infant back-arc basin developed along the Ryukyu arc. This paper provides new major and trace element and Sr-Nd-Pb-Li isotope data of volcanic rocks in the Okinawa Trough and combines the published geochemical data to discuss the composition of magma source, the influence of subduction component, and the contamination of crustal materials, and calculate the contribution between subduction sediment and altered oceanic crust in the subduction component. The results showed that there are 97% DM and 3% EMI component in the mantle source in middle trough (MS), which have been influenced by subduction sediment. The Li-Nd isotopes indicate that the contribution of subduction sediment and altered oceanic crust in subduction component are 4 and 96%, respectively. The intermediate-acidic rocks suffer from contamination of continental crust material in shallow magma chamber during fractional crystallization. The acidic rocks in south trough have experienced more contamination of crustal material than those from the middle and north trough segments.
The noon and midnight mid-latitude trough as seen by Ariel 4
NASA Technical Reports Server (NTRS)
Tulunay, Y. K.; Grebowsky, J. M.
1978-01-01
The electron density data returned by the polar orbiting satellites Ariel 3 and Ariel 4 revealed that the midlatitude trough is one of the distinct large-scale features of the ionosphere at about 550 km. Recent work (e.g., Tulunay and Grebowsky, 1975) on the data included the investigation of the temporal development of the latitudinal position of the midlatitude electron density trough at dawn and dusk during the large magnetic storms of May 1967 and May 1972. Model calculations which assumed that the equatorial convection E-field varies in step with the Kp index reproduced on the average the observed behavior. In the present paper, trough observations made at noon and midnight during the period, 12-21 December 1971 which encompassed a relatively large magnetic storm are discussed. In this context, model calculations have been employed as a guide of average approximations of the actual situation in predicting the plasmapause location. It is also shown that the trough observed on the noon passes is not generally plasmapause-related as the nightside troughs are expected to be.
Concentrating Solar Power Projects - Solnova 4 | Concentrating Solar Power
, 2017 Project Overview Project Name: Solnova 4 Country: Spain Location: Sevilla (Sanlúcar la Mayor Technology: Parabolic trough Status: Operational Country: Spain City: Sevilla Region: Sanlúcar la Mayor Lat
Concentrating Solar Power Projects - Solnova 1 | Concentrating Solar Power
, 2017 Project Overview Project Name: Solnova 1 Country: Spain Location: Sevilla (Sanlúcar la Mayor Technology: Parabolic trough Status: Operational Country: Spain City: Sevilla Region: Sanlúcar la Mayor Lat
Pennsylvanian-Permian tectonism in the Great Basin: The Dry Mountain trough and related basins
DOE Office of Scientific and Technical Information (OSTI.GOV)
Snyder, W.S.; Spinosa, C.; Gallegos, D.M.
1991-02-01
Pennsylvanian-Permian tectonism affected the continental margin of western North America from the Yukon to the Mojave Desert. Specific signatures of this tectonism include local angular unconformities, regional disconformities, renewed outpouring of clastic debris from a reactivated Antler and related highlands, and development of deeper water basins with anoxic sediments deposited below wave base. The basins formed include Ishbel trough (Canada), the Wood River basin (Idaho), Cassia basin, Ferguson trough, Dry Mountain trough (all Nevada), and unnamed basins in Death Valley-Mojave Desert region. The Dry Mountain trough (DMT) was initiated during early Wolfcampian and received up to 1,200 m of sedimentmore » by the late Leonardian. The lower contact is a regional unconformity with the Ely Limestone, or locally with the Diamond Peak or Vinini formations. Thus, following a period of localized regional uplift that destroyed the Ely basin, portions of the uplifted and exposed shelf subsided creating the Dry Mountain trough. Evidence suggesting a tectonic origin for the DMT includes (1) high subsidence rates (60-140 m/m.y.); (2) renewed influx of coarse clastic debris from the Antler highlands: (3) possible pre-Early Permian folding, thrusting, and tilting within the highlands; and (4) differential subsidence within the Dry Mountain trough, suggesting the existence of independent fault blocks.« less
Spectroscopic identification of SNe 2004ds and SN 2004dt
NASA Astrophysics Data System (ADS)
Gal-Yam, Avishay
2004-08-01
A. Gal-Yam, D. Fox and S. Kulkarni, California Institute of Technology, report on red spectra (range 550-780 nm) obtained by Kulkarni and Fox on Aug. 13.5 UT at the 10-m Keck I telescope (+ LRIS). The spectrum of of SN 2004ds (IAUC #8386), shows a broad, well-developed P-Cyg H_alpha line and suggests that this is a type II supernova. The spectrum of SN 2004dt (IAUC #8386), shows the distinctive Si II 6100 absorption trough around 6100 Angstrom, indicating this is a young SN Ia.
Belden, Sarah; Miller, Richard A.
2015-01-01
There is a growing demand for noninvasive anti-aging products for which the periorbital region serves as a critical aspect of facial rejuvenation. This article reviews a multitude of cosmeceutical ingredients that have good scientific data, specifically for the periorbital region. Topical treatment options have exponentially grown from extensively studied retinoids, to recently developed technology, such as growth factors and peptides. With a focus on the periorbital anatomy, the authors review the mechanisms of action of topical cosmeceutical ingredients, effectiveness of ingredient penetration through the stratum corneum, and validity of clinical trials. PMID:26430490
State-of-the-Art Review of Low-Cost Collector Technologies
1981-06-01
Mobility Low-Cost Parabolic Trough Survivability Light-Weight Thin-Film Reliability Heliostats Polymers Military 20. ABSTRACT (Contine an revers. deo It... heliostats and parabolic dish collectors. In addition several criteria were evaluated with respect to low-cost collector technologies These included...has produced collectors which incorporate sophisticated materials, = Heliostat heavy components, expensive seals and compli- o- (Point Focus) cated
Carbonate system at Iheya North in Okinawa Trough~IODP drilling and post drilling environment~
NASA Astrophysics Data System (ADS)
Noguchi, T.; Hatta, M.; Sunamura, M.; Fukuba, T.; Suzue, T.; Kimoto, H.; Okamura, K.
2012-12-01
The Iheya North hydrothermal field in middle Okinawa Trough is covered with thick hemipelagic and volcanic sediment. Geochemical characteristics of Okinawa Trough is to provide abundant of CO2, CH4, NH4, H2, and H2S which originated from magmatic gases, sedimentary organic matters. On this hydrothermal field, a scientific drilling by Integrated Ocean Drilling Program (IODP) Expedition 331 was conducted to investigate metabolically diverse subseafloor microbial ecosystem and their physical and chemical settings. To clarify the spatial distribution of physical condition beneath seafloor around the hydrothermal filed, we focus on the carbonate species analysis to reconstruct in-situ pH, which regulate the diversities of microbial community and mineral composition. We developed the small sample volume dissolved total inorganic carbon (DIC) analyzer and conducted the onboard analysis for the interstitial water during IODP Exp.331. Total alkalinity, boron, phosphate, and ammonium also analyzed for thermodynamic calculation. In this presentation, we represent the spatial distribution of pH beneath the Iheya North hydrothermal field. In addition, we developed a 128 bottles multiple water sampler (ANEMONE) for post drilling environmental monitoring. ANEMONE sampler was deployed on the manned submersible Shinkai 6500 with other chemical sensors (CTD, turbidity, pH, ORP, and H2S), and collected the hydrothermal plume samples every 5 minutes during YK12-05 cruise by R/V Yokosuka (Japan Agency for Marine-Earth Science and Technology, JAMSTEC). DIC concentration of plume samples collected by ANEMONE sampler were analyzed just after submersible retrieve, and nutrients, manganese, density, and total cell counts determination were conducted onshore analysis. Based on these results, we describe the spatial distribution of DIC and carbonate system on Iheya North hydrothermal field (interstitial water, hydrothermal fluid, and hydrothermal plume).
Concentrating Solar Power Projects - Abhijeet Solar Project | Concentrating
%) Technology: Parabolic trough Turbine Capacity: Net: 50.0 MW Gross: 50.0 MW Status: Under construction Start Ltd. Company: Ener-t International Ltd. Start Production: 2015 PPA/Tariff Rate: 12.24 Rs per kWh
Schenk, A.; Porter, A. L.; Alenciks, E.; Frazier, K.; Best, A. A.; Fraley, S. M.; Fraley, G. S.
2016-01-01
Controversy has developed as to whether or not pin-metered water lines or water troughs are more appropriate for Pekin ducks. We hypothesized that water troughs would show improved duck body conditions and environmental quality compared to pin-metered water lines. To test this hypothesis, we housed ducks in 2 barns, one with water lines and one with water troughs. Water troughs were constructed to meet RSPCA guidelines for number and density of ducks and with recently described verandas. Ducks were divided into 4 pens per barn (n = 1,000 ducks/pen). The study was then repeated (n = 8 pens per water source) in a cross-over design so the barns each contained the opposite water source to the first experiment. We scored the ducks’ body condition using an established scoring rubric and analyzed using SAS Proc GLM-Mix as binomial data. Ducks housed with water troughs showed higher (thus worse condition; P < 0.001) scores for eyes, nostrils, feather quality, feather cleanliness, and foot pads. We also compared water condition, water quality, and duck mortality using a Student t test for both water sources each week. We found that the water troughs showed higher iron (P < 0.001), nitrites (P < 0.001), pH (P < 0.01), and bacterial growth (P < 0.001). The bacterial growth was shown to have higher (P < 0.001) E. coli, coliforms, and Staphylococcus in the water troughs. Water lines typically showed no bacterial growth in culture-based assays. Ducks housed with water troughs used greater (P = 0.001) volumes of water compared to ducks housed with water lines. Ducks with water troughs also showed a greater percent (P = 0.008) mortality at all ages compared to ducks with water lines. These data suggest that water troughs may not be beneficial for duck welfare and could adversely impact both environment and duck or human health. PMID:26769272
Schenk, A; Porter, A L; Alenciks, E; Frazier, K; Best, A A; Fraley, S M; Fraley, G S
2016-04-01
Controversy has developed as to whether or not pin-metered water lines or water troughs are more appropriate for Pekin ducks. We hypothesized that water troughs would show improved duck body conditions and environmental quality compared to pin-metered water lines. To test this hypothesis, we housed ducks in 2 barns, one with water lines and one with water troughs. Water troughs were constructed to meet RSPCA guidelines for number and density of ducks and with recently described verandas. Ducks were divided into 4 pens per barn (n=1,000 ducks/pen). The study was then repeated (n=8 pens per water source) in a cross-over design so the barns each contained the opposite water source to the first experiment. We scored the ducks' body condition using an established scoring rubric and analyzed using SAS Proc GLM-Mix as binomial data. Ducks housed with water troughs showed higher (thus worse condition; P<0.001) scores for eyes, nostrils, feather quality, feather cleanliness, and foot pads. We also compared water condition, water quality, and duck mortality using a Student t test for both water sources each week. We found that the water troughs showed higher iron (P<0.001), nitrites (P<0.001), pH (P<0.01), and bacterial growth (P<0.001). The bacterial growth was shown to have higher (P<0.001)E. coli, coliforms, and Staphylococcusin the water troughs. Water lines typically showed no bacterial growth in culture-based assays. Ducks housed with water troughs used greater (P=0.001) volumes of water compared to ducks housed with water lines. Ducks with water troughs also showed a greater percent (P=0.008) mortality at all ages compared to ducks with water lines. These data suggest that water troughs may not be beneficial for duck welfare and could adversely impact both environment and duck or human health. © The Author 2016. Published by Oxford University Press on behalf of Poultry Science Association.
Full parabolic trough qualification from prototype to demonstration loop
NASA Astrophysics Data System (ADS)
Janotte, Nicole; Lüpfert, Eckhard; Pottler, Klaus; Schmitz, Mark
2017-06-01
On the example of the HelioTrough® collector development the full accompanying and supporting qualification program for large-scale parabolic trough collectors for solar thermal power plants is described from prototype to demonstration loop scale. In the evaluation process the actual state and the optimization potential are assessed. This includes the optical and geometrical performance determined by concentrator shape, deformation, assembly quality and local intercept factor values. Furthermore, its mechanical performance in terms of tracking accuracy and torsional stiffness and its thermal system performance on the basis of the overall thermal output and heat loss are evaluated. Demonstration loop tests deliver results of collector modules statistical slope deviation of 1.9 to 2.6 mrad, intercept factor above 98%, peak optical performance of 81.6% and heat loss coefficients from field tests. The benefit of such a closely monitored development lies in prompt feedback on strengths, weaknesses and potential improvements on the new product at any development stage from first module tests until demonstration loop evaluation. The product developer takes advantage of the achieved technical maturity, already before the implementation in a commercial power plant. The well-understood performance characteristics allow the reduction of safety margins making the new HelioTrough collector competitive from the start.
NASA Astrophysics Data System (ADS)
Horikawa, H.; Takaesu, M.; Sueki, K.; Takahashi, N.; Sonoda, A.; Miura, S.; Tsuboi, S.
2014-12-01
Mega-thrust earthquakes are anticipated to occur in the Nankai Trough in southwest Japan. In the source areas, we have deployed seafloor seismic network, DONET (Dense Ocean-floor Network System for Earthquake and Tsunamis), in 2010 in order to monitor seismicity, crustal deformations, and tsunamis. DONET system consists of totally 20 stations, which is composed of six kinds of sensors, including strong-motion seismometers and quartz pressure gauges. Those stations are densely distributed with an average spatial interval of 15-20 km and cover near the trench axis to coastal areas. Observed data are transferred to a land station through a fiber-optical cable and then to JAMSTEC (Japan Agency for Marine-Earth Science and Technology) data management center through a private network in real time. After 2011 off the Pacific coast of Tohoku Earthquake, each local government close to Nankai Trough try to plan disaster prevention scheme. JAMSTEC will disseminate DONET data combined with research accomplishment so that they will be widely recognized as important earthquake information. In order to open DONET data observed for research to local government, we have developed a web application system, REIS (Real-time Earthquake Information System). REIS is providing seismic waveform data to some local governments close to Nankai Trough as a pilot study. As soon as operation of DONET is ready, REIS will start full-scale operation. REIS can display seismic waveform data of DONET in real-time, users can select strong motion and pressure data, and configure the options of trace view arrangement, time scale, and amplitude. In addition to real-time monitoring, REIS can display past seismic waveform data and show earthquake epicenters on the map. In this presentation, we briefly introduce DONET system and then show our web application system. We also discuss our future plans for further developments of REIS.
& Impacts Analysis Group in the Strategic Energy Analysis Center. Areas of Expertise Life cycle environmental impacts of energy technologies, including externalities Life cycle assessment Sustainability ;Life Cycle Assessment of a Parabolic Trough Concentrating Solar Power Plant and the Impacts of Key
Concentrating Solar Power Projects - KVK Energy Solar Project |
%) Technology: Parabolic trough Turbine Capacity: Net: 100.0 MW Gross: 100.0 MW Status: Under construction Start °22' 55.0" North, 71°46' 23.0" East Contact(s): SolarPACES Start Production: March 2013 PPA
NASA Astrophysics Data System (ADS)
Ibarra, Mercedes; Gherboudj, Imen; Al Rished, Abdulaziz; Ghedira, Hosni
2017-06-01
Given ambitious plans to increase the amount of electricity production from renewable resources and the natural resources of the Kingdom of Saudi Arabia (KSA), solar energy stands as a technology with a great development potential in this country. In this work, the suitability of the territory is assess through a geospatial analysis, using a PTC performance model to account for the technical potential. As a result, a land suitability map is presented, where the North-West area of the country is identified as the one with more highly suitable area.
Facies mosaic in a fiord: Carboniferous-Permian Talchir Formation, India
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bose, P.K.; Mukhopadhyay, G.; Bhattacharya, H.N.
1988-01-01
Facies analysis of the basal 37m of the Carboniferous-Permian Talchir Formation is a glacier-fed bedrock trough in Dudhi nala, Bihar, India, provides insight into the pattern of sedimentation of course gravels in a fiord. Rapid transitions between 11 recognized facies, together with their complex organization, random variability in bed thickness, and differences in clast, shape, size, and composition indicate coalescence of fans developed from numerous point sources bordering the elongated trough. Converging slide masses and lodgment tillites on the slopes flanking the trough give way to sediment gravity flow deposits composed of an array of conglomerates (matrix and clast supportedmore » with normal, inverse of absence of grading), attendant turbidite sands, and prodelta mud. The rheology of the in-trough flows ranged from plastic laminar to fluidal turbulent in response to flow from slope to floor of the trough. Rapid calving of icebergs during the onset of deglaciation established a wave regime at the mouth of the trough and deposited cross-stratified sandstone replete with dripstones. The impact of large dripstones landing triggered turbidity currents. Continued rise in water level led to eventual preservation of the fan complex under onlapping wave-built shoal facies that grade into a sequence of upward-thinning hummocky cross-stratified sandstone beds virtually devoid of dripstones.« less
NASA Technical Reports Server (NTRS)
Kocin, P. J.; Uccellini, L. W.
1985-01-01
Surface and upper-level characteristics of selected meteorological fields are summarized. Two major types of sea level development are described and applied to the cases at hand, with a few storm systems showing characteristics of both types. Aspects such as rapid sea level deepening, coastal frontogenesis, cold air damming, low level jet formation, the development of an S-shaped isotherm pattern, diffluence downwind of a negatively tilted upper level trough axis, upper level confluence and an increase of geopotential heights at the base of the upper level trough characterized the pre-cyclogenetic and cyclogenetic periods of many of the storm systems. Large variability was also observed, especially with regard to the spatial dimensions of the surface and upper level systems, as well as variations in trough/ridge amplification and the evolution of upper level jet streak systems. The influence of transverse circulations associated with a confluent jet streak entrance region and the diffluent exit region of a jet streak/trough system on the production of snowfall is also discussed.
NASA Astrophysics Data System (ADS)
Harada, Tomoya; Satake, Kenji; Furumura, Takashi
2017-04-01
We carried out tsunami numerical simulations in the western Pacific Ocean and East China Sea in order to examine the behavior of massive tsunami outside Japan from the hypothetical M 9 tsunami source models along the Nankai Trough proposed by the Cabinet Office of Japanese government (2012). The distribution of MTHs (maximum tsunami heights for 24 h after the earthquakes) on the east coast of China, the east coast of the Philippine Islands, and north coast of the New Guinea Island show peaks with approximately 1.0-1.7 m,4.0-7.0 m,4.0-5.0 m, respectively. They are significantly higher than that from the 1707 Ho'ei earthquake (M 8.7), the largest earthquake along the Nankai trough in recent Japanese history. Moreover, the MTH distributions vary with the location of the huge slip(s) in the tsunami source models although the three coasts are far from the Nankai trough. Huge slip(s) in the Nankai segment mainly contributes to the MTHs, while huge slip(s) or splay faulting in the Tokai segment hardly affects the MTHs. The tsunami source model was developed for responding to the unexpected occurrence of the 2011 Tohoku Earthquake, with 11 models along the Nanakai trough, and simulated MTHs along the Pacific coasts of the western Japan from these models exceed 10 m, with a maximum height of 34.4 m. Tsunami propagation was computed by the finite-difference method of the non-liner long-wave equations with the Corioli's force and bottom friction (Satake, 1995) in the area of 115-155 ° E and 8° S-40° N. Because water depth of the East China Sea is shallower than 200 m, the tsunami propagation is likely to be affected by the ocean bottom fiction. The 30 arc-seconds gridded bathymetry data provided by the General Bathymetric Chart of the Oceans (GEBCO-2014) are used. For long propagation of tsunami we simulated tsunamis for 24 hours after the earthquakes. This study was supported by the"New disaster mitigation research project on Mega thrust earthquakes around Nankai/Ryukyu subduction zones", a project of Japan's Ministry of Education, Culture, Sports, Science and Technology (MEXT).
NASA Technical Reports Server (NTRS)
Selcuk, M. K.
1977-01-01
The usefulness of vee-trough concentrators in improving the efficiency and reducing the cost of collectors assembled from evacuated tube receivers was studied in the vee-trough/vacuum tube collector (VTVTC) project. The VTVTC was analyzed rigorously and various mathematical models were developed to calculate the optical performance of the vee-trough concentrator and the thermal performance of the evacuated tube receiver. A test bed was constructed to verify the mathematical analyses and compare reflectors made out of glass, Alzak and aluminized FEP Teflon. Tests were run at temperatures ranging from 95 to 180 C. Vee-trough collector efficiencies of 35 to 40% were observed at an operating temperature of about 175 C. Test results compared well with the calculated values. Predicted daily useful heat collection and efficiency values are presented for a year's duration of operation temperatures ranging from 65 to 230 C. Estimated collector costs and resulting thermal energy costs are presented. Analytical and experimental results are discussed along with a complete economic evaluation.
Rinse trough with improved flow
O'Hern, Timothy J.; Grasser, Thomas W.
1998-01-01
Novel rinse troughs accomplish thorough uniform rinsing. The troughs are suitable for one or more essentially planar objects having substantially the same shape. The troughs ensure that each surface is rinsed uniformly. The new troughs provide uniform rinse fluid flow over the objects' surfaces to accomplish a more thorough rinse than prior art troughs.
Geologic evolution of the Kastel trough and its implications on the Adiyaman oil fields, SE Turkey
DOE Office of Scientific and Technical Information (OSTI.GOV)
Coskun, Bu.
1990-05-01
Oil field developments of the Adiyaman area one of the main oil producing zones in southeast Turkey, have been highly influenced by geologic evolution of the Kastel trough which is situated in front of the suture zone between the Arabian and Anatolian plates. The Upper Cretaceous movements created many paleostructural trends in the Kastel trough where important dolomitic and porous reservoirs exist. The most important tectonic event, which appeared during the Upper Cretaceous movements, is the accumulation of the Kocali-Karadut ophiolitic complex, advancing from the north to the south in the Kastel trough, where heavy materials caused formation of amore » structural model favoring generation and migration and entrapment of oil in the reservoir rocks. Due to the presence of the Kocali-Karadut complex in the Kastel trough the following zones have been distinguished. (1) North Uplift Area. Situated under the allochthonous units, many thrust and reverse faults characterize this zone. The presence of paleohighs, where primary dolomites develop, allows the appearance of some oil fields in the region. This is the main future exploration zone in southeast Turkey. (2) Accumulation Area. Advancing from the north to the south, the allochthonous Kocali-Karadut complex filled the Kastel trough creating a deep graben whose flanks present generally normal faults. (3) Structural Belt. Important paleohighs constitute an exploration trend in this zone where dolomitic and porous carbonates contain actual oil fields. (4) South Accumulation Area. Distant from the Arabian-Anatolian suture zone, regional tectonics and sedimentology show this zone remained deeply buried during geologic time; good source rocks were deposited during the Cretaceous. (5) South Uplift Area. This area corresponds to the northern flank of the huge regional Mardin high in southeast Turkey where new oil fields have been discovered.« less
Rinse trough with improved flow
O`Hern, T.J.; Grasser, T.W.
1998-08-11
Novel rinse troughs accomplish thorough uniform rinsing. The troughs are suitable for one or more essentially planar objects having substantially the same shape. The troughs ensure that each surface is rinsed uniformly. The new troughs provide uniform rinse fluid flow over the objects` surfaces to accomplish a more thorough rinse than prior art troughs. 5 figs.
Molten salt parabolic trough system with synthetic oil preheating
NASA Astrophysics Data System (ADS)
Yuasa, Minoru; Hino, Koichi
2017-06-01
Molten salt parabolic trough system (MSPT), which can heat the heat transfer fluid (HTF) to 550 °C has a better performance than a synthetic oil parabolic trough system (SOPT), which can heat the HTF to 400 °C or less. The utilization of HTF at higher temperature in the parabolic trough system is able to realize the design of a smaller size of storage tank and higher heat to electricity conversion efficiency. However, with MSPT there is a great amount of heat loss at night so it is necessary to circulate the HTF at a high temperature of about 290 °C in order to prevent solidification. A new MSPT concept with SOPT preheating (MSSOPT) has been developed to reduce the heat loss at night. In this paper, the MSSOPT system, its performance by steady state analysis and annual performance analysis are introduced.
Kappel, William M.; Teece, Mark A.
2007-01-01
Introduction The U.S. Geological Survey, in cooperation with the Onondaga Lake Partnership and Onondaga Environmental Institute, has been studying the hydrogeology of the Onondaga Trough since 2002 to determine the movement and concentration of naturally occurring brine in the glacial valley-fill aquifer. Numerous shallow and deep test holes have been drilled to determine the glacial and water-quality stratigraphy in the Onondaga Trough. Organic materials were recovered from the Onondaga Creek, Ninemile Creek, and Harbor Brook valleys, and from lakebed sediments in Onondaga Lake (fig. 1) and age-dated with carbon-isotope analysis techniques. This report summarizes the carbon-isotope data collected from 1996 through 2006 in the Onondaga Trough. The results of these analyses provide a means to understand the deglaciation of the watershed and the development of the watershed from barren glacial sediment to a forested ecosystem.
Climatology of the winter Red Sea Trough
NASA Astrophysics Data System (ADS)
Awad, Adel M.; Almazroui, Mansour
2016-12-01
In this study, a new and objective method for detecting the Red Sea Trough (RST) was developed using mean sea level pressure (SLP) data from NCEP/NCAR reanalysis dataset from the winters of 1956 to 2015 to identify the Sudan Low and its trough. Approximately 96% of the winter RSTs were generated near two main sources, South Sudan and southeastern Sudan, and approximately 85% of these troughs were in four of the most outer areas surrounding the northern Red Sea. Moreover, from west to east of the Red Sea, the RST was affected by the relationships between the Siberian High and Azores High. The RST was oriented to the west when the strength of the Siberian High increased and to the east when the strength of the Azores High increased. Furthermore, the synoptic features of the upper level of the RST emphasize the impacts of subtropical anticyclones at 850 hPa on the orientation of the RST, the impacts of the northern cyclone trough and the maximum wind at a pressure level of 250 hPa. The average static stability between 1000 hPa and 500 hPa demonstrated that the RST followed the northern areas of low static stability. The results from previous studies were confirmed by a detailed case study of the RST that extended to its central outermost area. The results of a detailed case study of the short RST indicated that the trough becomes shorter with increasing static stability and that the Azores and Siberian high-pressure systems influence the northern region of the trough while the maximum upper wind shifts south of the climate position.
Katabatic jumps in the Martian northern polar regions
NASA Astrophysics Data System (ADS)
Spiga, Aymeric; Smith, Isaac
2018-07-01
Martian polar regions host active regional wind circulations, such as the downslope katabatic winds which develop owing to near-surface radiative cooling and sloped topography. Many observations (stratigraphy from radar profiling, frost streaks, spectral analysis of ices) concur to show that aeolian processes play a key role in glacial processes in Martian polar regions. A spectacular manifestation of this resides in elongated clouds that forms within the polar spiral troughs, a series of geological depressions in Mars' polar caps. Here we report mesoscale atmospheric modeling in Martian polar regions making use of five nested domains operating a model downscaling from horizontal resolutions of twenty kilometers to 200 m in a typical polar trough. We show that strong katabatic jumps form at the bottom of polar troughs with an horizontal morphology and location similar to trough clouds, large vertical velocity (up to +3 m/s) and temperature perturbations (up to 20 K) propitious to cloud formation. This strongly suggests that trough clouds on Mars are caused by katabatic jumps forming within polar troughs. This phenomena is analogous to the terrestrial Loewe phenomena over Antarctica's slopes and coastlines, resulting in a distinctive "wall of snow" during katabatic events. Our mesoscale modeling results thereby suggest that trough clouds might be present manifestations of the ice migration processes that yielded the internal cap structure discovered by radar observations, as part of a "cyclic step" process. This has important implications for the stability and possible migration over geological timescales of water ice surface reservoirs-and, overall, for the evolution of Mars' polar caps over geological timescales.
NASA Astrophysics Data System (ADS)
Yamashita, M.; Nakanishi, A.; Moore, G. F.; Kodaira, S.; Nakamura, Y.; Miura, S.; Kaneda, Y.
2016-12-01
Great earthquakes with tsunamis with recurrence intervals of 100-200 years have occurred along the Nankai Trough near central Japan where the Shikoku Basin is subducting with thick sediments on the Philippine Sea plate. To predict the exact height of the tsunami on the coast region generated by these large ruptures, it is important to estimate the vertical deformation that occurs on the seaward end of the rupture area. Recent drilling results have also yielded evidence not only of splay faults that generate tsunamigenic rupture, but also new evidence of tsunamigenic rupture along the frontal thrust at the trench axis in the Nankai Trough. In order to understand the deformation around the frontal thrust at the trench axis, we conducted a dense high-resolution seismic reflection survey with 10-20 km spacing over 1500 km of line length during 2013 and 2014. Clear seismic reflection images of frontal thrusts in the accretionary prism and subducting Shikoku Basin, image deformation along the trench axis between off Muroto Cape and off Ashizuri Cape. The cumulative displacement along the frontal thrust and second thrust are measured from picked distinct reflectors in depth-converted profiles. The average value of cumulative displacement of the frontal thrust is more than 100 m within 2 km depth beneath the seafloor. The location of highest displacement of 300 m displacement agree with the seaward end of slip distribution of the 1946 Nankai event calculated by numerical simulations. We also evaluate the seaward structure for understanding the future rupture distribution. The protothrust zone (PTZ) consisting of many incipient thrusts is identifiable in the portion of trough-fill sediments seaward of the frontal thrust. In order to emphasize the characteristics of frontal thrust and PTZ, we construct the detailed relief image for focusing on the lineated slope of the PTZ at the trough axis. Although our surveys covered a part of Nankai seismogenic zone, it is important to evaluate the initiation and evolution of frontal thrust at the toe of Nankai trough axis. This study is part of "Research project for compound disaster mitigation on the great earthquakes and tsunamis around the Nankai Trough region" funded by the Ministry of Education, Culture, Sports, Science, and Technology of Japan.
NASA Astrophysics Data System (ADS)
Sasaki, T.; Lim, J.; Higashi, M.; Park, J.
2010-12-01
The Nankai Trough is known as one of the best-suited convergent plate margins for studying accretionary prism growth as well as subduction zone earthquakes. Along the Nankai accretionary margin off southwest Japan, the Shikoku Basin which formed 26-15 Ma as backarc spreading in the Philippine Sea Plate is being subducted about 4 cm/year to the northwest. The Deep Sea Drilling Project (DSDP) and Ocean Drilling Program (ODP) penetrated the Nankai accretionary prism and the incoming sedimentary section along the Ashizuri and Muroto transects, off Shikoku Island. Also, Integrated Ocean Drilling Program (IODP), which represented just one part of a multi-stage project known as the Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE) has been conducting drilling cruises now. IODP Expedition 322 in 2009, the coring was carried out at two drilling sites on the northern part of the Shikoku Basin in the subducting Philippine Sea plate. One of the major achievements of Expedition 322 is a discovery of late Miocene (10.2-7.6 Ma) tuffaceous and volcaniclastic sandstone layer (Underwood et al., IODP Prel. Rept. 322, 2009) that has not been previously recognized in the Nankai Trough. Based on age and volcanic sand content analysis, these volcaniclastic layers were unique to the Shikoku Basin off Kii Peninsula. The closest source of this volcanic layer was supposed to be the Izu-Bonin arc. Subducted sediments ultimately affect subduction zone geochemistry, thermal structure, and seismogenesis. High porosity of the volcaniclastic sandstone layer suggests the transportation of fluid to the subduction zone, it might affect the initiation and evolution of the decollement zone or plate boundary fault in the Nankai Trough. We interpreted single channel and multichannel seismic reflection profiles that have been acquired in the Nankai Trough margin by Japan Agency for Marine-Earth Science and Technology (JAMSTEC) since the year of 1997. We tried to map the major seismic layers such as volcaniclastic layer, volcanic ash layer and turbidite layers which were found at drilling sites in the IODP Expedition 322 in the northern Shikoku Basin. As a result, we recognized that these prominent seismic layers are widely distributed in the northern Shikoku Basin. In this talk, we will show specific seismic layers directly connecting to the decollement at the Nankai Trough axis, and discuss its implications for subduction processes in the Nankai Trough margin.
Corrugated pipe adhesive applicator apparatus
Shirey, R.A.
1983-06-14
Apparatus for coating selected portions of the troughs of a corrugated pipe with an adhesive includes a support disposed within the pipe with a reservoir containing the adhesive disposed on the support. A pump, including a spout, is utilized for supplying the adhesive from the reservoir to a trough of the pipe. A rotatable applicator is supported on the support and contacts the trough of the pipe. The applicator itself is sized so as to fit within the trough, and contacts the adhesive in the trough and spreads the adhesive in the trough upon rotation. A trough shield, supported by the support and disposed in the path of rotation of the applicator, is utilized to prevent the applicator from contacting selected portions of the trough. A locator head is also disposed on the support and provides a way for aligning the spout, the applicator, and the trough shield with the trough. 4 figs.
Concentrating Solar Power Projects - Colorado Integrated Solar Project |
Energy's Cameo Station's Unit 2 (approximately 2 MWe equivalent) in order to decrease the overall MW Status: Currently Non-Operational Start Year: 2010 Do you have more information, corrections, or comments? Background Technology: Parabolic trough Status: Currently Non-Operational Country: United States
Concentrating Solar Power Projects - La Dehesa | Concentrating Solar Power
| NREL Dehesa This page provides information on La Dehesa, a concentrating solar power (CSP : March 20, 2017 Project Overview Project Name: La Dehesa Country: Spain Location: La Garrovilla (Badajoz ? Background Technology: Parabolic trough Status: Operational Country: Spain City: La Garrovilla Region
USAF solar thermal applications overview
NASA Technical Reports Server (NTRS)
Hauger, J. S.; Simpson, J. A.
1981-01-01
Process heat applications were compared to solar thermal technologies. The generic process heat applications were analyzed for solar thermal technology utilization, using SERI's PROSYS/ECONOMAT model in an end use matching analysis and a separate analysis was made for solar ponds. Solar technologies appear attractive in a large number of applications. Low temperature applications at sites with high insolation and high fuel costs were found to be most attractive. No one solar thermal technology emerges as a clearly universal or preferred technology, however,, solar ponds offer a potential high payoff in a few, selected applications. It was shown that troughs and flat plate systems are cost effective in a large number of applications.
Evaluation of parasitic consumption for a CSP plant
NASA Astrophysics Data System (ADS)
Ramorakane, Relebohile John; Dinter, Frank
2016-05-01
With the continuous development and desire to build alternative effective and efficient power plants, Concentrated Solar Power (CSP) plants (and more specifically the Parabolic Trough CSP Plants) have proven to be one of the alternative energy resources for the future. On this regard more emphasis and research is being employed to better this power plant technology, where one of the main challenges to these plants is to improve their efficiency by optimizing the parasitic load, wherein one of the major causes of the power plants' reduced overall efficiency arises from their parasitic load consumption. This project is therefore aimed at evaluating the parasitic load on Andasol 3 Power Plant, which is a 50 MW Parabolic Trough Power Plant with a 7.5 hours of full load storage system. It was hence determined that the total power plant's parasitic load consumption is about 12% in summer season and between 16% and 24% in winter season. In an effort to improve the power plant's efficiency, a couple of measures to reduce the parasitic load consumption were recommended, and also an alternative and cheaper source of parasitic load feeding plant, during the day (when the parasitic load consumption is highest) was proposed/recommended.
NASA Technical Reports Server (NTRS)
Selcuk, M. K.
1979-01-01
The Vee-Trough/Vacuum Tube Collector (VTVTC) aimed to improve the efficiency and reduce the cost of collectors assembled from evacuated tube receivers. The VTVTC was analyzed rigorously and a mathematical model was developed to calculate the optical performance of the vee-trough concentrator and the thermal performance of the evacuated tube receiver. A test bed was constructed to verify the mathematical analyses and compare reflectors made out of glass, Alzak and aluminized GEB Teflon. Tests were run at temperatures ranging from 95 to 180 C during the months of April, May, June, July and August 1977. Vee-trough collector efficiencies of 35-40 per cent were observed at an operating temperature of about 175 C. Test results compared well with the calculated values. Test data covering a complete day are presented for selected dates throughout the test season. Predicted daily useful heat collection and efficiency values are presented for a year's duration at operation temperatures ranging from 65 to 230 C. Estimated collector costs and resulting thermal energy costs are presented. Analytical and experimental results are discussed along with an economic evaluation.
Low-Cost, Light Weight, Thin Film Solar Concentrator
NASA Technical Reports Server (NTRS)
Ganapathi, G.; Palisoc, A.; Nesmith, B.; Greschik, G.; Gidanian, K.; Kindler, A.
2013-01-01
This research addresses a cost barrier towards achieving a solar thermal collector system with an installed cost of $75/sq m and meet the Department of Energy's (DOE's) performance targets for optical errors, operations during windy conditions and lifetime. Current concentrators can cost as much as 40-50% of the total installed costs for a CSP plant. In order to reduce the costs from current $200-$250/sq m, it is important to focus on the overall system. The reflector surface is a key cost driver, and our film-based polymer reflector will help significantly in achieving DOE's cost target of $75/sq m. The ease of manufacturability, installation and replacement make this technology a compelling one to develop. This technology can be easily modified for a variety of CSP options including heliostats, parabolic dishes and parabolic troughs.
ASCOT: A Collaborative Platform for the Virtual Observatory
NASA Astrophysics Data System (ADS)
Marcos, D.; Connolly, A. J.; Krughoff, K. S.; Smith, I.; Wallace, S. C.
2012-09-01
The digital networks are changing the way that knowledge is created, structured, curated, consumed, archived and referenced. Projects like Wikipedia, Github or Galaxy Zoo have shown the potential of online communities to develop and communicate ideas. ASCOT is a web based framework that facilitates collaboration among astronomers providing a simple way to share, explore, interact and analyze large amounts of data from a broad range of sources available trough the Virtual Observatories (VO). Designed with a strong emphasis on usability, ASCOT takes advantage of the latest generation of web standards and cloud technologies to implement an extendable and customizable stack of web tools and services.
NASA Astrophysics Data System (ADS)
Nishizawa, A.; Kaneda, K.; Oikawa, M.; Horiuchi, D.; Fujioka, Y.; Okada, C.
2017-12-01
Several depressions found under the thick sediments in the East China Sea shelf have been considered as failed rift basins. Their formation age becomes progressively younger from NW to SE and the youngest rift basin is the Okinawa Trough, an active backarc basin of the Ryukyu (Nansei-Shoto) arc-trench system, to the southwest of Kyusyu, Japan. Its rifting is in progress and related hydrothermal activity is present in the trough. The knowledge of the crustal structure of the trough is fundamental to understand the current active tectonics and predict the future of the trough. We, Japan Coast Guard, have conducted extensive seismic reflection and refraction surveys in the Ryukyu region since 2008 and compiled the seismic structures of the Okinawa Trough. We will show the crustal structures along seven along-trough and ten across-trough seismic survey lines. The P-wave velocity models beneath the Okinawa Trough generally show a thinned continental/island arc crust consisting of upper, middle, and lower crusts. Moho depths below the trough were estimated mainly from Moho reflection (PmP) travel times. The crustal thickness of the trough is thinner than those of the East China Sea shelf and of the Ryukyu Islands. The depth of the Moho below the trough decreases from over 30 km in the north to about 13 km in the south, indicating a difference in degree of the rifting process. The position of the shallowest Moho along the across-trough lines in the northern trough does not necessarily correspond to the center of the trough defined as the deepest water depth, but it corresponds to the transition area between the East China Sea shelf and the Okinawa Trough. An M7.1 earthquake occurred at the transition area on Nov. 14, 2015 (JST) and many aftershocks were observed along the transition. This seismic activity demonstrated that the area is under rifting tectonics in the present.
Directed flow fluid rinse trough
Kempka, Steven N.; Walters, Robert N.
1996-01-01
Novel rinse troughs accomplish thorough uniform rinsing. The tanks are suitable for one or more essentially planar items having substantially the same shape. The troughs ensure that each surface is rinsed uniformly. The new troughs also require less rinse fluid to accomplish a thorough rinse than prior art troughs.
Directed flow fluid rinse trough
Kempka, S.N.; Walters, R.N.
1996-07-02
Novel rinse troughs accomplish thorough uniform rinsing. The tanks are suitable for one or more essentially planar items having substantially the same shape. The troughs ensure that each surface is rinsed uniformly. The new troughs also require less rinse fluid to accomplish a thorough rinse than prior art troughs. 9 figs.
Cambrian potential indicated in Kentucky Rome trough
DOE Office of Scientific and Technical Information (OSTI.GOV)
Harris, D.C.; Drahovzal, J.A.
1996-02-19
This paper reviews recent gas discoveries in the Kentucky Rome trough and the implications for future developments. It reviews the geology and stratigraphy of this structure and identifies the potential zones of production and trapping mechanisms. It provides results from geologic logs and seismic data to provide cross sectional and structural interpretations. Finally it discusses the gas composition of natural gas recovered from the basin.
Scheel, Jennifer; Reber, Sandra; Stoessel, Lisa; Waldmann, Elisabeth; Jank, Sabine; Eckardt, Kai-Uwe; Grundmann, Franziska; Vitinius, Frank; de Zwaan, Martina; Bertram, Anna; Erim, Yesim
2017-03-29
Different measures of non-adherence to immunosuppressant (IS) medication have been found to be associated with rejection episodes after successful transplantation. The aim of the current study was to investigate whether graft rejection after renal transplantation is associated with patient-reported IS medication non-adherence and IS trough level variables (IS trough level variability and percentage of sub-therapeutic IS trough levels). Patient-reported non-adherence, IS trough level variability, percentage of sub-therapeutic IS trough levels, and acute biopsy-proven late allograft rejections were assessed in 267 adult renal transplant recipients who were ≥12 months post-transplantation. The rate of rejection was 13.5%. IS trough level variability, percentage of sub-therapeutic IS trough levels as well as patient-reported non-adherence were all significantly and positively associated with rejection, but not with each other. Logistic regression analyses revealed that only the percentage of sub-therapeutic IS trough levels and age at transplantation remained significantly associated with rejection. Particularly, the percentage of sub-therapeutic IS trough levels is associated with acute rejections after kidney transplantation whereas IS trough level variability and patient-reported non-adherence seem to be of subordinate importance. Patient-reported non-adherence and IS trough level variables were not correlated; thus, non-adherence should always be measured in a multi-methodological approach. Further research concerning the best combination of non-adherence measures is needed.
NASA Astrophysics Data System (ADS)
1985-12-01
Topics related to aerospace power are discussed, taking into account trends and issues of military space power systems technology, space station power system advanced development, the application and use of nuclear power for future spacecraft, the current status of advanced solar array technology development, the application of a parabolic trough concentrator to space station power needs, life test results of the Intelsat-V nickel-cadmium battery, and metal hydride hydrogen storage in nickel hydrogen batteries. Other subjects explored are concerned with alternative fuels, biomass energy, biomedical power, coal gasification, electric power cycles, and electric propulsion. Attention is given to an advanced terrestrial vehicle electric propulsion systems assessment, fuel cells as electric propulsion power plants, a sinewave synthesis for high efficiency dc-ac conversion, steam desulfurization of coal, leadless transfer of energy into the body to power implanted blood pumps, oil production via entrained flow pyrolysis of biomass, and a New Zealand synthetic gasoline plant.
Concentrating Solar Power Projects - Astexol II | Concentrating Solar Power
(Badajoz) Owner(s): Elecnor/Aries/ABM AMRO (100%) Technology: Parabolic trough Turbine Capacity: Net: 50.0 Difference: 100°C Power Block Turbine Capacity (Gross): 50.0 MW Turbine Capacity (Net): 50.0 MW Output Type indirect Storage Capacity: 8 Hours Thermal Storage Description:
NASA Astrophysics Data System (ADS)
Maccari, Augusto; Donnola, Sandro; Matino, Francesca; Tamano, Shiro
2016-05-01
Since July 2013, the first stand-alone Molten Salt Parabolic Trough (MSPT) demo plant, which was built in collaboration with Archimede Solar Energy and Chiyoda Corporation, is in operation, located adjacent to the Archimede Solar Energy (ASE) manufacturing plant in Massa Martana (Italy). During the two year's operating time frame, the management of the demo plant has shown that MSPT technology is a suitable and reliable option. Several O&M procedures and tests have been performed, as Heat Loss and Minimum Flow Test, with remarkable results confirming that this technology is ready to be extended to standard size CSP plant, if the plant design takes into account molten salt peculiarities. Additionally, the plant has been equipped on fall 2014 with a Steam Generator system by Chiyoda Corporation, in order to test even this important MSPT plant subsystem and to extend the solar field active time, overcoming the previous lack of an adequate thermal load. Here, a description of the plant improvements and the overall plant operation figures will be presented.
Laser welding on trough panel: 3D body part
NASA Astrophysics Data System (ADS)
Shirai, Masato; Hisano, Hirohiko
2003-03-01
Laser welding for automotive bodies has been introduced mainly by European car manufacturers since more than 10 years ago. Their purposes of laser welding introduction were mainly vehicle performance improvement and lightweight. And laser welding was applied to limited portion where shapes of panels are simple and easy to fit welded flanges. Toyota also has introduced laser welding onto 3 dimensional parts named trough panel since 1999. Our purpose of the introduction was common use of equipment. Trough panel has a complex shape and different shapes in each car type. In order to realize common use of welding equipment, we introduced parts locating equipment which had unique, small & simple jigs fo each car type and NC (Numerical Controlled) locators and air-cooled small laser head developed by ourselves to the trough welding process. Laser welding replaced spot welding and was applied linearly like stitches. Length of laser welding was determined according to comparison with statistic tensile strength and fatigue strength of spot welding.
NASA Astrophysics Data System (ADS)
Moore, B. J.; Bosart, L. F.; Keyser, D.
2013-12-01
During late October 2007, the interaction between a deep polar trough and Tropical Cyclone (TC) Kajiki off the eastern Asian coast perturbed the North Pacific jet stream and resulted in the development of a high-amplitude Rossby wave train extending into North America, contributing to three concurrent high-impact weather events in North America: wildfires in southern California associated with strong Santa Ana winds, a cold surge into eastern Mexico, and widespread heavy rainfall (~150 mm) in the south-central United States. Observational analysis indicates that these high-impact weather events were all dynamically linked with the development of a major high-latitude ridge over the eastern North Pacific and western North America and a deep trough over central North America. In this study, global operational ensemble forecasts from the European Centre for Medium-Range Weather Forecasts (ECMWF) obtained from The Observing System Research and Predictability Experiment (THORPEX) Interactive Grand Global Ensemble (TIGGE) archive are used to characterize the medium-range predictability of the large-scale flow pattern associated with the three events and to diagnose the large-scale atmospheric processes favorable, or unfavorable, for the occurrence of the three events. Examination of the ECMWF forecasts leading up to the time period of the three high-impact weather events (~23-25 October 2007) indicates that ensemble spread (i.e., uncertainty) in the 500-hPa geopotential height field develops in connection with downstream baroclinic development (DBD) across the North Pacific, associated with the interaction between TC Kajiki and the polar trough along the eastern Asian coast, and subsequently moves downstream into North America, yielding considerable uncertainty with respect to the structure, amplitude, and position of the ridge-trough pattern over North America. Ensemble sensitivity analysis conducted for key sensible weather parameters corresponding to the three high-impact weather events, including relative humidity, temperature, and precipitation, demonstrates quantitatively that all three high-impact weather events are closely linked with the development of the ridge-trough pattern over North America. Moreover, results of this analysis indicate that the development of the ridge-trough pattern is modulated by DBD and cyclogenesis upstream over the central and eastern North Pacific. Specifically, ensemble members exhibiting less intense cyclogenesis and a more poleward cyclone track over the central and eastern North Pacific feature the development of a poleward-displaced ridge over the eastern North Pacific and western North America and a cut-off low over the Intermountain West, an unfavorable scenario for the occurrence the three high-impact weather events. Conversely, ensemble members exhibiting more intense cyclogenesis and a less poleward cyclone track feature persistent ridging along the western coast of North America and trough development over central North America, establishing a favorable flow pattern for the three high-impact weather events. Results demonstrate that relatively small initial differences in the large-scale flow pattern over the North Pacific among ensemble members can result in large uncertainty in the forecast downstream flow response over North America.
NASA Astrophysics Data System (ADS)
Hui, Pinhong; Fang, Juan
2016-06-01
Two persistent heavy rainfall (PHR) events in the middle and lower reaches of Yangtze River (MLYR) occurring in June 1982 and 1998 are studied in this paper. Though both events happened in the Meiyu season, their large-scale background and developing processes were quite different. During the PHR event in 1982, the Lake Baikal area was occupied by a strong westerly trough and the western Pacific subtropical high (WPSH) was stronger and more westward-extending than the normal years. Under such a condition, the cold-dry air and warm-moist air were continuously transported to the MLYR and favored the PHR there. For the event in 1998, the WPSH was similar to that in 1982, while the westerly trough in the Lake Baikal area was comparatively weak and a shortwave trough situating in East China contributed to advect cold-dry air to the MLYR. It is found that the high-latitude trough was closely related to the 10-30-day low-frequency oscillation while the anomaly of WPSH was linked with the combined effect of both 30-60- and 10-30-day low-frequency oscillations in the PHR event in 1982. By contrast, the 60-day low-pass perturbation demonstrated positive impact on the westward extension of WPSH and development of the Baikal trough while the 30-60-day oscillation played a role in strengthening the shortwave trough in East China and the WPSH in the case of 1998. Though the low-latitude 30-60-day oscillations contributed to the intensification and westward extension of the WPSH in both PHR events, their evolution exhibited evident differences. In the 1982 case, the 30-60-day anomalies originated from the western Indian Ocean were much more like the Madden-Julian Oscillation, while its counterpart in the 1998 case was much more similar to the first mode of the boreal summer intraseasonal oscillation.
SHARAD Radar investigations into the initiation of spiral troughs on Planum Boreum, Mars
NASA Astrophysics Data System (ADS)
Smith, I. B.; Holt, J. W.
2010-12-01
Recent evidence demonstrates that the prominent spiral troughs of the North Polar Layered Deposits (NPLD) on Mars are not young features, having persisted and evolved during accumulation of more than 500 meters of ice [Smith and Holt, Nature, 2010]. Because of the rich stratigraphy in the NPLD, determining the processes controlling trough formation and evolution is an important step in understanding the history of ice and climate on Mars. Multiple periods of trough initiation are observed in radar data collected by the Shallow Radar (SHARAD) instrument on Mars Reconnaissance Orbiter; however, the mechanism behind trough initiation is still a mystery. Discrete radar reflectors can be associated with the onset of spiral troughs because of their stratigraphic relationships: below the reflectors the troughs do not exist, and above the troughs begin to take shape. To address the question of trough formation we have mapped these reflectors, which are assumed to represent isochrones, in more than 400 SHARAD observations throughout the NPLD. Taken together these represent the surfaces where troughs initiated, i.e. surfaces that lie directly below the first appearance of troughs. When observation geometries are favorable, we find that the onset of each trough rests on a change in slope usually at the base of a buried erosional scarp. The underlying layers end abruptly at the scarps rather than diminish or pinch out with distance, suggesting that the NPLD underwent cap-wide erosion predating trough formation. This surface morphology provides the initial conditions needed to form troughs from the combination of deposition and katabatic winds affected by surface slope. Radar observations indicate that the troughs initiated and evolved with approximately the same wavelength as can be measured today. Thus proposed hypotheses of small bedforms growing into larger wavelength structures is not supported. Locally, the unconformable contact between younger, trough-related material and older eroded surfaces is exposed at the surface. Neither the younger nor older exposed layers show small-scale bedforms, supporting this conclusion. At least two initiation surfaces can be observed in the radar data within the uppermost 500 m of the NPLD. Alternating periods of erosion and deposition are predicted to result from large changes in obliquity and insolation at the Martian north pole [Laskar et al., Nature, 2004], suggesting that trough initiation may be related to orbital forcing.
2006-06-11
This MOC image shows a wide, flat-floored trough flanked by several smaller, branching troughs in the Olympica Fossae region of Mars. Dark- and intermediate-toned slope streaks -- created by dry avalanches of dust -- occur on the trough walls
O+ trough zones in the polar cap ionosphere-magnetosphere coupling region
NASA Astrophysics Data System (ADS)
Horwitz, James; Zeng, Wen; Jaafari, Fajer
Regions of low-density troughs in O+ have been observed at 1 RE altitude in the polar cap ionosphere-magnetosphere region by the Thermal Ion Dynamics Experiment(TIDE) on the POLAR spacecraft. In this presentation, the UT Arlington Dynamic Fluid-Kinetic (DyFK) code is employed to investigate the formation of such O+ density troughs. We utilize convection paths of flux tubes in the high-latitude region as prescribed by an empirical convection model with solar wind inputs to track the evolution of ionospheric plasma transport and in particular O+ densities along these tubes with time/space. The flux tubes are subjected to auroral processes of precipitation and wave-driven ion heating when they pass through the auroral oval, which tends to elevate the plasma densities in these tubes. When the F-regions of such tubes traverse locations where the F-region is in darkness, recombination there causes the higher-altitude regions to drain and the densities to decline throughout. Owing to the varying effects of these processes, significant and low trough-like densities at higher altitudes developed along these flux tubes. The modeled densities near 6000 km altitudes will be compared with multiple POLAR passes featuring POLAR/TIDE-measured O+ densities for inside and outside of such trough regions.
Improvement Design of Parabolic Trough
NASA Astrophysics Data System (ADS)
Ihsan, S. I.; Safian, M. A. I. M.; Taufek, M. A. M.; Mohiuddin, A. K. M.
2017-03-01
The performance of parabolic trough solar collector (PTSC) has been evaluated using different heat transfer working fluids; namely water and SAE20 W50 engine oil. New and slightly improved PTSC was developed to run the experimental study. Under the meteorological conditions of Malaysia, authors found that PTSC can operate at a higher temperature than water collector but the performance efficiency of collector using engine oil is much lower than the water collector.
NASA Astrophysics Data System (ADS)
Ajayi, C. O.; Ajakaiye, D. E.
1981-12-01
The origin of the Benue trough has been a controversial subject. Previous workers in the area have evolved several theories ranging from a rift, with or without plate tectonic concepts (King, 1950; Wright, 1968, 1970; Burke et al., 1970; Grant, 1971; Olade, 1975) to a geosyncline (Lees, 1952) and a combination of both (Cratchley and Jones, 1965; Offodile, 1976) to explain the origin of the trough. One of the aims of the gravity survey, carried out in the middle Benue and discussed in this paper, was to attempt to resolve some of the problems associated with the origin of the trough as proposed by previous workers and in so doing to explain the geological peculiarities associated with the trough. Interpretations of the gravity data along two north—south profiles in the survey area indicated the existence of a rift, of normal width (about 40 km) buried under the Cretaceous cover and located between the central axis (ridge) of the trough and the northern boundary of the trough. The gravity minimum which occurs south of the central axis of the trough, was also ascribed to another rift. Thus the Benue trough is considered to consist of two parallel rifts separated by the axial ridge which partly explains the abnormal width of the trough. The interpreted models also indicate a low-angle thrust fault, with a small displacement, which may be related to the folding of the sediments in the trough and also to the asymmetry of the trough. Furthermore, the gravity data suggest that oceanic crust might not have reached the ground surface in the Benue trough, as in the Red Sea, before rifting ceased.
NASA Astrophysics Data System (ADS)
Padhy, S.; Furumura, T.; Maeda, T.
2017-12-01
The Okinawa Trough is a young continental back-arc basin located behind the Ryukyu subduction zone in southwestern Japan, where the Philippine Sea Plate dives beneath the trough, resulting in localized mantle upwelling and crustal thinning of the overriding Eurasian Plate. The attenuation structure of the plates and surrounding mantle in this region associated with such complex tectonic environment are poorly documented. Here we present seismological evidence for these features based on the high-resolution waveform analyses and 3D finite difference method (FDM) simulation. We analyzed regional broadband waveforms recorded by F-net (NIED) of in-slab events (M>4, H>100 km). Using band-passed (0.5-8 Hz), mean-squared envelopes, we parameterized coda-decay in terms of rise-time (time from P-arrival to maximum amplitude in P-coda), decay-time (time from maximum amplitude to theoretical S-arrival), and energy-ratio defined as the ratio of energy in P-coda to that in direct P wave. The following key features are observed. First, there is a striking difference in S-excitation along paths traversing and not traversing the trough: events from SW Japan not crossing the trough show clear S waves, while those occurring in the trough show very weak S waves at a station close to the volcanic front. Second, some trough events exhibit spindle-shaped seismograms with strong P-coda excitation, obscuring the development of S waves, at back-arc stations; these waveforms are characterized by high decay-time (>10s) and high energy-ratio (>>1.0), suggesting strong forward scattering along ray paths. Third, some trough events show weak S-excitation characterized by low decay-time (<5s) and low energy-ratio (<1.0) at fore-arc stations, suggesting high intrinsic absorption. To investigate the mechanism of the observed anomalies, we will conduct FDM simulation for a suite of models comprising the key subduction features like localized mantle-upwelling and crustal thinning expected in the region. It is expected that simulation results help to resolve rift-induced crust and upper mantle anomalies in the trough showing maximum waveform distortion as we observed in broadband records, and will enhance understanding of tectonic processes related to back-arc rifting in the region.
NASA Astrophysics Data System (ADS)
Yasuda, K.; Tadokoro, K.; Ikuta, R.; Watanabe, T.; Fujii, C.; Matsuhiro, K.; Sayanagi, K.
2014-12-01
Seafloor crustal deformation is crucial for estimating the interplate locking at the shallow subduction zone and has been carried out at subduction margins in Japan, e.g., Japan Trench and Nankai Trough [Sato et al., 2011; Tadokoro et al., 2012]. Iinuma et al. [2012] derived slip distributions during the 2011 Tohoku-Oki earthquake using GPS/Acoustic data and on-land GPS data. The result showed that maximum slip is more than 85 m near the trench axis. The focal area along the Nankai trough extended to the trough axis affected this earthquake by cabinet office, government of Japan. We monitored seafloor crustal deformation along the Nankai trough, Japan. Observation regions are at the eastern end of Nankai trough (named Suruga trough) and at the central Nankai trough. We established and monitored by two sites across the trough at each region. In the Suruga trough region, we repeatedly observed from 2005 to 2013. We observed 13 and 14 times at a foot wall side (SNE) and at a hanging wall side (SNW), respectively. We estimated the displacement velocities with relative to the Amurian plate from the result of repeated observation. The estimated displacement velocity vectors at SNE and SNW are 42±8 mm/y to N94±3˚W direction and 39±11 mm/y to N84±9˚W direction, respectively. The directions are the same as those measured at the on-land GPS stations. The magnitudes of velocity vector indicate significant shortening by approximately 4 mm/y between SNW and on-land GPS stations at hanging wall side of the Suruga Trough. This result shows that the plate interface at the northernmost Suruga trough is strongly locked. In the central Nankai trough region, we established new two stations across the central Nankai trough (Both stations are about 15km distance from trough) and observed only three times, August 2013, January 2014, and June 2014. We report the results of monitoring performed in this year.
Can industry afford solar energy
NASA Astrophysics Data System (ADS)
Kreith, F.; Bezdek, R.
1983-03-01
Falling oil prices and conservation measures have reduced the economic impetus to develop new energy sources, thus decreasing the urgency for bringing solar conversion technologies to commercial readiness at an early date. However, the capability for solar to deliver thermal energy for industrial uses is proven. A year-round operation would be three times as effective as home heating, which is necessary only part of the year. Flat plate, parabolic trough, and solar tower power plant demonstration projects, though uneconomically operated, have revealed engineering factors necessary for successful use of solar-derived heat for industrial applications. Areas of concern have been categorized as technology comparisons, load temperatures, plant size, location, end-use, backup requirements, and storage costs. Tax incentives have, however, supported home heating and not industrial uses, and government subsidies have historically gone to conventional energy sources. Tax credit programs which could lead to a 20% market penetration by solar energy in the industrial sector by the year 2000 are presented.
Four Stages of Research on the Educational Use of Ubiquitous Computing
ERIC Educational Resources Information Center
Laru, Jari; Naykki, Piia; Järvelä, Sanna
2015-01-01
In this paper, the Gartner Group's hype cycle is used as the basis for categorizing and analyzing research on the educational use of ubiquitous computing. There are five phases of the hype cycle: the technology trigger, the peak of inflated expectations, the trough of disillusionment, the slope of enlightenment, and the plateau of productivity.…
Concentrating Solar Power Projects - Majadas I | Concentrating Solar Power
: March 20, 2017 Project Overview Project Name: Majadas I Country: Spain Location: Majadas de Tiétar (Cà comments? Background Technology: Parabolic trough Status: Operational Country: Spain City: Majadas de Tià : Biphenyl/Diphenyl oxide Solar-Field Outlet Temp: 393°C Power Block Turbine Capacity (Gross): 50.0 MW
3D Porosity Estimation of the Nankai Trough Sediments from Core-log-seismic Integration
NASA Astrophysics Data System (ADS)
Park, J. O.
2015-12-01
The Nankai Trough off southwest Japan is one of the best subduction-zone to study megathrust earthquake fault. Historic, great megathrust earthquakes with a recurrence interval of 100-200 yr have generated strong motion and large tsunamis along the Nankai Trough subduction zone. At the Nankai Trough margin, the Philippine Sea Plate (PSP) is being subducted beneath the Eurasian Plate to the northwest at a convergence rate ~4 cm/yr. The Shikoku Basin, the northern part of the PSP, is estimated to have opened between 25 and 15 Ma by backarc spreading of the Izu-Bonin arc. The >100-km-wide Nankai accretionary wedge, which has developed landward of the trench since the Miocene, mainly consists of offscraped and underplated materials from the trough-fill turbidites and the Shikoku Basin hemipelagic sediments. Particularly, physical properties of the incoming hemipelagic sediments may be critical for seismogenic behavior of the megathrust fault. We have carried out core-log-seismic integration (CLSI) to estimate 3D acoustic impedance and porosity for the incoming sediments in the Nankai Trough. For the CLSI, we used 3D seismic reflection data, P-wave velocity and density data obtained during IODP (Integrated Ocean Drilling Program) Expeditions 322 and 333. We computed acoustic impedance depth profiles for the IODP drilling sites from P-wave velocity and density data. We constructed seismic convolution models with the acoustic impedance profiles and a source wavelet which is extracted from the seismic data, adjusting the seismic models to observed seismic traces with inversion method. As a result, we obtained 3D acoustic impedance volume and then converted it to 3D porosity volume. In general, the 3D porosities show decrease with depth. We found a porosity anomaly zone with alteration of high and low porosities seaward of the trough axis. In this talk, we will show detailed 3D porosity of the incoming sediments, and present implications of the porosity anomaly zone for the megathrust fault behavior.
Maximova, Natalia; Gregori, Massimo; Simeone, Roberto; Sonzogni, Aurelio; Boz, Giulia; Fucile, Carmen; Marini, Valeria; Martelli, Antonietta; Mattioli, Francesca
2017-09-08
42 pediatric patients with iron overload, who underwent liver biopsy and DFX treatment after hematopoietic stem cell transplantation were included in the study group. The patients were divided into two groups diversified according to deferasirox trough plasma concentrations (DFX C trough ) with cut-off equal to10 mcg/mL. The average dose of DFX was 25.9 mg/kg in the DFX C trough < 10 mcg/mL group versus 19.2 mg/kg in the DFX C trough > 10 mcg/mL group ( p =0,0003). The mean duration of DFX treatment was 135.7 days in the DFX C trough < 10 mcg/mL group versus 41.8 days in the DFX C trough > 10 mcg/mL group ( p <0.0001). The mean tissue iron concentration in the DFX C trough < 10 mcg/mL group was 261.9 μmol/g versus 133.4 μmol/g in the DFX C trough > 10 mcg/mL group ( p < 0.0001). 21 patients (100%) in the DFX C trough > 10 mcg/mL group had ductopenia which was complete in 47.6% of them and severe in 52.4%. All patients with particularly high C trough (> 25 mcg/mL) were found to have total ductopenia. 90.5% of all deferasirox-related adverse events and 100% of major adverse events occurred in the DFX C trough > 10 mcg/mL group. In the DFX C trough < 10 mcg/mL group only one patient interrupted chelation therapy versus 16 (84.2%) patients in the DFX C trough > 10 mcg/mL group. We would recommend a close monitoring in pediatric hematopoietic transplant recipients subjected to deferasirox-based therapy because we have observed a high incidence of adverse events and discontinuation of chelation treatment.
NASA Astrophysics Data System (ADS)
Takano, Osamu; Tateishi, Masaaki; Endo, Masataka
2005-05-01
The Pliocene Tamugigawa Formation in the Niigata-Shin'etsu inverted rift basin, Northern Fossa Magna, located in the junction zone of the NE and SW Japan arcs, demonstrates a trough-fill turbidite system, which is topographically controlled in depositional style and shows notable contrasts in depositional architecture from sandy radial-fan-type turbidite systems. The Tamugigawa trough-fill turbidite system shows an elongated morphology parallel to the basin extent and facies associations consisting of trough-fill, lateral-supply and trough-side elements. The trough-fill elements comprise thick-bedded sheet sandstone and sheet-flow turbidite associations, which show sheet-like sedimentation configuration, instead of depositional lobes, without distinct upward fining and coarsening successions. The lateral-supply elements form an intra-trough small fan along a lateral sediment-supply system into the troughs, and consist mainly of coarser-grained distributary-channel fills and sheet sandstones. The trough-side elements consist of slope-mudstone and spillover associations, which were deposited on the structural highs beside the troughs. The Tamugigawa trough-fill turbidites were deposited through three phases: (a) initial ponding stage with thick, sheet sandstones provided by the lateral-supply system, (b) main filling stage with sheet-flow turbidites provided by the longitudinal supply system, and (c) filled-up stage characterized by minor-scale channel-levee systems. Basin-wide tectono-sedimentary studies reveal that the trough-fill turbidites were characteristically formed during the compressional-stress-field stage related to basin inversion. The compressional stress induced basin-floor syndepositional folding and coarse clastic supply from the uplifted provenance, resulting in topographically restricted turbidite deposition within the troughs. In contrast, turbidites of the post-rift stage, prior to basin inversion, show no topographical control because of the simple and wide rift-basin topography, relative to the amount of sediment supply. It is concluded that the trough-fill turbidites of the Niigata-Shin'etsu basin have been strongly affected by basin tectonics in their depositional architecture and formation phases.
The Effect of Age and Weight on Vancomycin Serum Trough Concentrations in Pediatric Patients
Madigan, Theresa; Sieve, Ronald M.; Graner, Kevin K.; Banerjee, Ritu
2013-01-01
Background Vancomycin treatment failure has been associated with low serum vancomycin trough concentrations, prompting recommendations to increase the daily doses in adults and children. Despite more aggressive vancomycin dosing, there continues to be significant variability in vancomycin trough concentrations in pediatric patients. Methods To determine if vancomycin trough concentrations in pediatric patients differ by age and weight, we reviewed records of hospitalized patients who received vancomycin between 2008 and 2012. Patients were divided into groups that received vancomycin 40 mg/kg/day (2008 to 2009) or 60 mg/kg/day (2010 to 2012). Vancomycin trough concentrations were compared between groups and within the 60-mg/kg/day group, stratified by patient age and weight. Results After increasing the vancomycin dose from 40 mg/kg/day to 60 mg/kg/day, initial trough concentrations increased significantly in patients younger than 2 and greater than 6 years of age, but not in patients between the ages of 2 and 5 years. In the 60-mg/kg/day group, only 16.7% of patients between 2 and 5 years of age had initial trough concentrations in the therapeutic range (10 mcg/mL to 20 mcg/mL). Initial trough concentrations were therapeutic in a greater proportion of patients ages 6 years to 12 years (38.7%) and 13 years to 18 years (63.0%). Patients between the ages of 13 and 18 had the highest proportion of supratherapeutic initial vancomycin trough concentrations (14.8%). Patients weighing > 50 kg had significantly higher trough concentrations than patients ≤ 50 kg (17.1 mcg/mL vs. 9.3 mcg/mL; p<0.001). Conclusion Although increasing the vancomycin dose from 40 mg/kg/day to 60 mg/kg/day led to a significant increase in vancomycin trough concentrations, a large proportion of patients receiving 60 mg/kg/day of vancomycin had trough concentrations outside of the therapeutic range. Specifically, patients younger than 6 years tend to have low trough concentrations, while adolescents and children > 50 kg are more likely to have elevated trough concentrations. Vancomycin dosing strategies in pediatric patients should consider age and weight as well as renal function and indication. PMID:23864541
NASA Technical Reports Server (NTRS)
2006-01-01
25 June 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows v-shaped troughs in the Hephaestus Fossae region of Mars. Light-toned, windblown ripples reside in the very lowest parts of the troughs, as well as on the cratered upland outside the troughs. Boulders and other types of debris, which were derived from the layered rock exposed near the top of the troughs, are seen resting on the trough floors and perched on the sloping trough walls. Location near: 21.1oN, 236.7oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern SpringAllegra, S; Cusato, J; De Francia, S; Arduino, A; Longo, F; Pirro, E; Massano, D; De Nicolò, A; Piga, A; D'Avolio, A
2018-05-22
β-Thalassemia patients develop deficiency in vitamin D absorption and liver hydroxylation, resulting in extremely low calcitriol levels. We explored the role of single-nucleotide polymorphisms (SNPs) involved in vitamin D metabolism, transport and activity on deferasirox pharmacokinetics and outcomes (effectiveness trough levels (C trough ) and the area under the curve (AUC) cutoffs of 20 μg ml -1 and 360 μg ml -1 h -1 , respectively; nonresponse AUC limit of 250 μg ml -1 h -1 ). Ninety-nine β-thalassemic patients were enrolled. Drug plasma C trough and AUC were measured by the high-performance liquid chromatography system coupled with an ultraviolet determination method. Allelic discrimination for VDR, CYP24A1, CYP27B1 and GC gene SNPs was performed by real-time PCR. CYP24A1 22776 TT significantly influenced C min and negatively predicted it in regression analysis. CYP24A1 3999 CC was associated with C trough and C min and was a negative predictor of T max , whereas CYP24A1 8620 GG seemed to have a role in C trough , AUC, t 1/2 and C min , and was an AUC negative predictor factor. Considering treatment outcome, Cdx2 and GC 1296 were retained in regression analysis as AUC efficacy cutoff negative predictors.
Solar photovoltaic reflective trough collection structure
Anderson, Benjamin J.; Sweatt, William C.; Okandan, Murat; Nielson, Gregory N.
2015-11-19
A photovoltaic (PV) solar concentration structure having at least two troughs encapsulated in a rectangular parallelepiped optical plastic structure, with the troughs filled with an optical plastic material, the troughs each having a reflective internal surface and approximately parabolic geometry, and the troughs each including photovoltaic cells situated so that light impinging on the optical plastic material will be concentrated onto the photovoltaic cells. Multiple structures can be connected to provide a solar photovoltaic collection system that provides portable, efficient, low-cost electrical power.
AFGL Fiscal Year 1989. Air Force Technical Objectives Document
1988-10-01
analyzing and forecasting atmospheric parameters. The critical technologies are cloud and precipitation effects, atmospheric boundary effects, climatology for...on the morphology and dynamics of auroral electron and ion precipitation using existing and future satellite data bases. The research will specify the...other ground based diagnostics. In the transport and particle precipitation dominated regions of polar cap, oval, and trough, research efforts are
Concentrating Solar Power Projects - La Africana | Concentrating Solar
: Posadas (Córdoba) Owner(s): Ortiz/TSK/Magtel (100%) Technology: Parabolic trough Turbine Capacity: Net -Field Outlet Temp: 393°C Solar-Field Temp Difference: 100°C Power Block Turbine Capacity (Gross): 50.0 MW Turbine Capacity (Net): 50.0 MW Output Type: Steam Rankine Cooling Method: Wet cooling Thermal
De Cock, R. F. W.; Allegaert, K.; Vanhaesebrouck, S.; Danhof, M.; Knibbe, C. A. J.
2015-01-01
Based on a previously derived population pharmacokinetic model, a novel neonatal amikacin dosing regimen was developed. The aim of the current study was to prospectively evaluate this dosing regimen. First, early (before and after second dose) therapeutic drug monitoring (TDM) observations were evaluated for achieving target trough (<3 mg/liter) and peak (>24 mg/liter) levels. Second, all observed TDM concentrations were compared with model-predicted concentrations, whereby the results of a normalized prediction distribution error (NPDE) were considered. Subsequently, Monte Carlo simulations were performed. Finally, remaining causes limiting amikacin predictability (i.e., prescription errors and disease characteristics of outliers) were explored. In 579 neonates (median birth body weight, 2,285 [range, 420 to 4,850] g; postnatal age 2 days [range, 1 to 30 days]; gestational age, 34 weeks [range, 24 to 41 weeks]), 90.5% of the observed early peak levels reached 24 mg/liter, and 60.2% of the trough levels were <3 mg/liter (93.4% ≤5 mg/liter). Observations were accurately predicted by the model without bias, which was confirmed by the NPDE. Monte Carlo simulations showed that peak concentrations of >24 mg/liter were reached at steady state in almost all patients. Trough values of <3 mg/liter at steady state were documented in 78% to 100% and 45% to 96% of simulated cases with and without ibuprofen coadministration, respectively; suboptimal trough levels were found in patients with postnatal age <14 days and current weight of >2,000 g. Prospective evaluation of a model-based neonatal amikacin dosing regimen resulted in optimized peak and trough concentrations in almost all patients. Slightly adapted dosing for patient subgroups with suboptimal trough levels was proposed. This model-based approach improves neonatal dosing individualization. PMID:26248375
Structure of the lower crust beneath the Carolina Trough, U.S. Atlantic continental margin
Tréhu, Anne M.; Ballard, A.; Dorman, L.M.; Gettrust, J.F.; Klitgord, Kim D.; Schreiner, A.
1989-01-01
Data from three large-offset seismic profiles provide information on the crustal structure beneath the Carolina trough. The profiles, obtained by the U.S. Geological Survey, the Naval Oceanographic Research Development Agency, and the Scripps Institution of Oceanography in 1985, were oriented parallel to the trough and were located (1) seaward of the East Coast Magnetic Anomaly (ECMA), which is generally thought to represent the boundary between oceanic and continental crust; (2) along the axis of the trough between the ECMA and the hinge zone, which is thought to reflect the landward limit of highly stretched and altered transitional crust; and (3) along the Carolina platform landward of the basement hinge zone on crust thought to have been thinned only slightly during rifting. These data constrain the velocity structure of the lower crust and provide evidence for a thick lens of high-velocity (>7.1 km/s) lower crustal material that extends beneath the Carolina trough and the adjacent ocean basin. This lens reaches a maximum thickness of about 13 km beneath the deepest part of the trough, thins to about 5 km seaward of the ECMA, and is either very thin or absent landward of the hinge zone. It is interpreted to represent material that was underplated beneath and/or intruded into the crust during the late stage of continental rifting and that led to an anomalously thick plutonic layer during the early seafloor spreading phase. These data thus support the recent conclusions of White et al. (1987b) and Mutter et al. (1988) that the initiation of seafloor spreading is attended in many, if not most, cases by the generation of an anomalously large volume of melt.
Optical analysis of a photovoltaic V-trough system installed in western India.
Maiti, Subarna; Sarmah, Nabin; Bapat, Pratap; Mallick, Tapas K
2012-12-20
The low concentrating photovoltaic (PV) system such as a 2× V-trough system can be a promising choice for enhancing the power output from conventional PV panels with the inclusion of thermal management. This system is more attractive when the reflectors are retrofitted to the stationary PV panels installed in a high aspect ratio in the north-south direction and are tracked 12 times a year manually according to preset angles, thus eliminating the need of diurnal expensive tracking. In the present analysis, a V-trough system facing exactly the south direction is considered, where the tilt angle of the PV panels' row is kept constant at 18.34°. The system is installed on the terrace of CSIR-Central Salt and Marine Chemicals Research Institute in Bhavnagar, Gujarat, India (21.47 N, 71.15 E). The dimension of the entire PV system is 9.64 m×0.55 m. The V-troughs made of anodized aluminum reflectors (70% specular reflectivity) had the same dimensions. An in-house developed; experimentally validated Monte Carlo ray-trace model was used to study the effect of the angular variation of the reflectors throughout a year for the present assembly. Results of the ray trace for the optimized angles showed the maximum simulated optical efficiency to be 85.9%. The spatial distribution of solar intensity over the 0.55 m dimension of the PV panel due to the V-trough reflectors was also studied for the optimized days in periods that included solstices and equinoxes. The measured solar intensity profiles with and without the V-trough system were used to calculate the actual optical efficiencies for several sunny days in the year, and results were validated with the simulated efficiencies within an average error limit of 10%.
Spatial patterns of cyanobacterial mat growth on sand ripples
NASA Astrophysics Data System (ADS)
Mariotti, G.; Klepac-Ceraj, V.; Perron, J. T.; Bosak, T.
2016-02-01
Photosynthetic microbial mats produce organic matter, cycle nutrients, bind pollutants and stabilize sediment in sandy marine environments. Here, we investigate the influence of bedforms and wave motion on the growth rate, composition and spatial variability of microbial mats by growing cyanobacterial mats on a rippled bed of carbonate sand in a wave tank. The tank was forced with an oscillatory flow with velocities below the threshold for sediment motion yet able to induce a porewater flow within the sediment. Different spatial patterns developed in mats depending on the initial biochemistry of the water medium. When growing in a medium rich in nitrogen, phosphorous and micronutrients, mats grew faster on ripple troughs than on ripple crests. After two months, mats covered the bed surface uniformly, and the microbial communities on the crests and in the troughs had similar compositions. Differences in bed shear stress and nutrient availability between crests and troughs were not able to explain the faster growth in the troughs. We hypothesize that this growth pattern is due to a "strainer" effect, i.e. the suspended bacteria from the inoculum were preferentially delivered to troughs by the wave-induced porewater flow. In the experiments initiated in a medium previously used up by a microbial mat and thus depleted in nutrients, mats grew preferentially on the ripple crests. This spatial pattern persisted for nearly two years, and the microbial composition on troughs and crests was different. We attribute this pattern to the upwelling of porewater in the crests, which increased the delivery of nutrients from sediment to the cyanobacteria on the bed surface. Thus, the macroscopic patterns formed by photosynthetic microbial mats on sand ripples may be used to infer whether mats are nutrient-limited and whether they are recently colonized or older than a month.
NASA Astrophysics Data System (ADS)
Lantzsch, Hendrik; Hanebuth, Till J. J.; Horry, Jan; Grave, Marina; Rebesco, Michele; Schwenk, Tilmann
2017-10-01
High-resolution sediment echosounder data combined with radiocarbon-dated sediment cores allowed us to reconstruct the Late Quaternary stratigraphic architecture of the Kveithola Trough and surrounding Spitsbergenbanken. The deposits display the successive deglacial retreat of the Svalbard-Barents Sea Ice Sheet. Basal subglacial till indicates that the grounded ice sheet covered both bank and trough during the Late Weichselian. A glaciomarine blanket inside the trough coinciding with laminated plumites on the bank formed during the initial ice-melting phase from at least 16.1 to 13.5 cal ka BP in close proximity to the ice margin. After the establishment of open-marine conditions at around 13.5 cal ka BP, a sediment drift developed in the confined setting of the Kveithola Trough, contemporary with crudely laminated mud, an overlying lag deposit, and modern bioclastic-rich sand on Spitsbergenbanken. The Kveithola Drift shows a remarkable grain-size coarsening from the moat towards the southern flank of the trough. This trend contradicts the concept of a separated drift (which would imply coarser grain sizes in proximity of the moat) and indicates that the southern bank is the main sediment source for the coarse material building up the Kveithola Drift. This depocenter represents, therefore, a yet undescribed combination of off-bank wedge and confined drift. Although the deposits inside Kveithola Trough and on Spitsbergenbanken display different depocenter geometries, time-equivalent grain-size changes imply a region-wide sediment-dynamic connection. We thus relate a phase of coarsest sediment supply (8.8-6.3 cal ka BP) to an increase in bottom current strength, which might be related to a stronger Atlantic Water inflow from the Southeast across the bank leading to winnowing and off-bank export of sandy sediments.
Low-cost small scale parabolic trough collector design for manufacturing and deployment in Africa
NASA Astrophysics Data System (ADS)
Orosz, Matthew; Mathaha, Paul; Tsiu, Anadola; Taele, B. M.; Mabea, Lengeta; Ntee, Marcel; Khakanyo, Makoanyane; Teker, Tamer; Stephens, Jordan; Mueller, Amy
2016-05-01
Concentrating Solar Power is expanding its deployment on the African subcontinent, highlighting the importance of efforts to indigenize manufacturing of this technology to increase local content and therefore local economic benefits of these projects. In this study a design for manufacturing (DFM) exercise was conducted to create a locally produced parabolic trough collector (the G4 PTC). All parts were sourced or fabricated at a production facility in Lesotho, and several examples of the design were prototyped and tested with collaborators in the Government of Lesotho's Appropriate Technology Services division and the National University of Lesotho. Optical and thermal performance was simulated and experimentally validated, and pedagogical pre-commercial versions of the PTC have been distributed to higher education partners in Lesotho and Europe. The cost to produce the PTC is 180 USD/m2 for a locally manufactured heat collection element (HCE) capable of sustaining 250C operation at ~65% efficiency. A version with an imported evacuated HCE can operate at 300°C with 70% efficiency. Economically relevant applications for this locally produced PTC include industrial process heat and distributed generation scenarios where cogeneration is required.
NASA Astrophysics Data System (ADS)
Orosz, Matthew; Zweibaum, Nicolas; Lance, Tamir; Ruiz, Maritza; Morad, Ratson
2016-05-01
Sunlight to electricity efficiencies of Parabolic Trough Collector (PTC) plants are typically on the order of 15%, while commercial solar Photovoltaic (PV) technologies routinely achieve efficiencies of greater than 20%, albeit with much higher conversion efficiencies of photons at the band gap. Hybridizing concentrating solar power and photovoltaic technologies can lead to higher aggregate efficiencies due to the matching of photons to the appropriate converter based on wavelength. This can be accomplished through spectral filtering whereby photons unusable or poorly utilitized by PV (IR and UV) are passed through to a heat collection element, while useful photons (VIS) are reflected onto a concentrating PV (CPV) receiver. The mechanical design and experimental validation of spectral splitting optics is described in conjunction with system level modeling and economic analysis. The implications of this architecture include higher efficiency, lower cost hybrid CSP-PV power systems, as well as the potential to retrofit existing PTC plants to boost their output by ~ 10% at a projected investment cost of less than 1 per additional net Watt and an IRR of 18%, while preserving the dispatchability of the CSP plant's thermal energy storage.
DETAIL VIEW OF ARRASTRA, LOOKING SOUTHEAST. THIS OLD TECHNOLOGY IS ...
DETAIL VIEW OF ARRASTRA, LOOKING SOUTHEAST. THIS OLD TECHNOLOGY IS AN ANACHRONISM OF THIS MILL. ORE WAS DUMPED INTO THE STONE LINED TROUGH. AS THE ARRASTRA TURNED LARGE STONES CONNECTED TO THE FOUR ARMS WERE DRAGGED AROUND OVER THE ORE TO CRUSH IT. IT IS CLEAR THAT THIS ARRASTRA WAS POWERED BY MACHINE THOUGH IT IS UNCLEAR EXACTLY HOW IT WAS POWERED. THE WHITE PINE TALC MINE OPENING IS SEEN IN THE DISTANCE AT THE CENTER LEFT EDGE. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA
Paleocene Pacific Plate reorganization mirrored in formation of the Suvarov Trough, Manihiki Plateau
NASA Astrophysics Data System (ADS)
Pietsch, Ricarda; Uenzelmann-Neben, Gabriele
2016-10-01
The Suvarov Trough is a graben structure that deviates from the Danger Islands Troughs within the Manihiki Plateau, a Large Igneous Province (LIP) located in the Central Pacific. New high-resolution seismic reflection data provide evidence that the graben formed in two phases during the Paleocene (65-45 Ma). In a first phase extension occurred in southwestward direction, pulling apart the northern part of the Suvarov Trough and a parallel trending unnamed trough. In a second phase a change of extensional force direction occurred from southwest to west-northwest, forming the southern part of the Suvarov Trough that extends onto the High Plateau. The formation of the Suvarov Trough is accompanied by a series of normal fault systems that apparently formed simultaneously. Comparing the seismic results to existing Pacific paleo strain reconstructions, the timing of increased strain and local deformation direction fits well to our findings. We thus suggest that the multiple strike directions of the Suvarov Trough represent an extensional structure that was caused by the major, stepwise Pacific Plate reorganization during the Paleocene.
Hua, B; Lee, A; Fan, L; Li, K; Zhang, Y; Poon, M-C; Zhao, Y
2017-05-01
Pharmacokinetics (PK) modelling suggests improvement of trough levels are achieved by using more frequent infusion strategy. However, no clinical study data exists to confirm or quantify improvement in trough level, particularly for low-dose prophylaxis in patients with haemophilia A. To provide evidence that low dose daily (ED) prophylaxis can increase trough levels without increasing FVIII consumption compared to every-other-day (EOD) infusion. A cross-over study on 5 IU kg -1 FVIII daily vs. 10 IU kg -1 EOD infusions, each for 14 days was conducted at the PUMCH-HTC. On the ED schedule, trough (immediate prior to infusion), and peak FVIII:C levels (30 min after infusion) were measured on days 1-5; and trough levels alone on days 7, 9, 11 and 13. For the EOD schedule, troughs, peaks and 4-h postinfusion were measured on day 1; troughs and peaks on days 3, 5, and 7; troughs alone on days 9, 11 and 13 and 24-h postinfusion on days 2, 4 and 6. FVIII inhibitors were assessed on days 0 and 14 during both infusion schedules. Six patients were enrolled. PK evidence showed that daily prophylaxis achieved higher (~2 times) steady-state FVIII trough levels compared to EOD with the same total factor consumption. The daily prophylaxis had good acceptability among patients and reduced chronic pain in the joints in some patients. Our PK study shows low-dose factor VIII daily infusion results in higher trough level than with EOD infusion with similar factor VIII consumption in Chinese adult haemophilia A patients. © 2017 John Wiley & Sons Ltd.
Are Vancomycin Trough Concentrations Adequate for Optimal Dosing?
Youn, Gilmer; Jones, Brenda; Jelliffe, Roger W.; Drusano, George L.; Rodvold, Keith A.; Lodise, Thomas P.
2014-01-01
The current vancomycin therapeutic guidelines recommend the use of only trough concentrations to manage the dosing of adults with Staphylococcus aureus infections. Both vancomycin efficacy and toxicity are likely to be related to the area under the plasma concentration-time curve (AUC). We assembled richly sampled vancomycin pharmacokinetic data from three studies comprising 47 adults with various levels of renal function. With Pmetrics, the nonparametric population modeling package for R, we compared AUCs estimated from models derived from trough-only and peak-trough depleted versions of the full data set and characterized the relationship between the vancomycin trough concentration and AUC. The trough-only and peak-trough depleted data sets underestimated the true AUCs compared to the full model by a mean (95% confidence interval) of 23% (11 to 33%; P = 0.0001) and 14% (7 to 19%; P < 0.0001), respectively. In contrast, using the full model as a Bayesian prior with trough-only data allowed 97% (93 to 102%; P = 0.23) accurate AUC estimation. On the basis of 5,000 profiles simulated from the full model, among adults with normal renal function and a therapeutic AUC of ≥400 mg · h/liter for an organism for which the vancomycin MIC is 1 mg/liter, approximately 60% are expected to have a trough concentration below the suggested minimum target of 15 mg/liter for serious infections, which could result in needlessly increased doses and a risk of toxicity. Our data indicate that adjustment of vancomycin doses on the basis of trough concentrations without a Bayesian tool results in poor achievement of maximally safe and effective drug exposures in plasma and that many adults can have an adequate vancomycin AUC with a trough concentration of <15 mg/liter. PMID:24165176
Aguilera Díaz, Jerónimo; Arias, Antonio Eduardo; Budalich, Cintia Mabel; Benítez, Sonia Elizabeth; López, Gastón; Borbolla, Damián; Plazzotta, Fernando; Luna, Daniel; de Quirós, Fernán González Bernaldo
2010-01-01
This paper describes the development and implementation of a web based electronic health record for the Homecare Service program in the Hospital Italiano de Buenos Aires. It reviews the process of the integration of the new electronic health record to the hospital information system, allowing physicians to access the clinical data repository from their Pc's at home and with the capability of consulting past and present history of the patient health care, order, tests, and referrals with others professionals trough the new Electronic Health Record. We also discuss how workflow processes were changed and improved for the physicians, nurses, and administrative personnel of the Homecare Services and the educational methods used to improve acceptance and adoption of these new technologies. We also briefly describe the validation of physicians and their field work with electronic signatures.
NASA Astrophysics Data System (ADS)
Pagola, Iñigo; Funcia, Ibai; Sánchez, Marcelino; Gil, Javier; González-Vallejo, Victoria; Bedoya, Maxi; Orellana, Guillermo
2017-06-01
The work presented in this paper offers a robust, effective and economically competitive method for online detection and monitoring of the presence of molecular hydrogen in the heat transfer fluids of parabolic trough collector plants. The novel method is based on a specific fluorescent sensor according to the ES2425002 patent ("Method for the detection and quantification of hydrogen in a heat transfer fluid").
NASA Technical Reports Server (NTRS)
2004-01-01
[figure removed for brevity, see original site] This week we will be looking at five examples of laminar wind flow on the north polar cap. On Earth, gravity-driven south polar cap winds are termed 'catabatic' winds. Catabatic winds begin over the smooth expanse of the cap interior due to temperature differences between the atmosphere and the surface. Once begun, the winds sweep outward along the surface of the polar cap toward the sea. As the polar surface slopes down toward sealevel, the wind speeds increase. Catabatic wind speeds in the Antartic can reach several hundreds of miles per hour. In the images of the Martian north polar cap we can see these same type of winds. Notice the streamers of dust moving downslope over the darker trough sides, these streamers show the laminar flow regime coming off the cap. Within the trough we see turbulent clouds of dust, kicked up at the trough base as the winds slow down and enter a chaotic flow regime. The horizontal lines in these images are due to framelet overlap and lighting conditions over the bright polar cap. Image information: VIS instrument. Latitude 86.5, Longitude 64.5 East (295.5 West). 40 meter/pixel resolution. Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.NASA Technical Reports Server (NTRS)
2004-01-01
[figure removed for brevity, see original site]
This week we will be looking at five examples of laminar wind flow on the north polar cap. On Earth, gravity-driven south polar cap winds are termed 'catabatic' winds. Catabatic winds begin over the smooth expanse of the cap interior due to temperature differences between the atmosphere and the surface. Once begun, the winds sweep outward along the surface of the polar cap toward the sea. As the polar surface slopes down toward sealevel, the wind speeds increase. Catabatic wind speeds in the Antartic can reach several hundreds of miles per hour. In the images of the Martian north polar cap we can see these same type of winds. Notice the streamers of dust moving downslope over the darker trough sides, these streamers show the laminar flow regime coming off the cap. Within the trough we see turbulent clouds of dust, kicked up at the trough base as the winds slow down and enter a chaotic flow regime. The horizontal lines in these images are due to framelet overlap and lighting conditions over the bright polar cap. Image information:VIS instrument. Latitude 86.5, longitude 57.4 East (302.6 West). 40 meter/pixel resolution. Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.NASA Technical Reports Server (NTRS)
2004-01-01
[figure removed for brevity, see original site] This week we will be looking at five examples of laminar wind flow on the north polar cap. On Earth, gravity-driven south polar cap winds are termed 'catabatic' winds. Catabatic winds begin over the smooth expanse of the cap interior due to temperature differences between the atmosphere and the surface. Once begun, the winds sweep outward along the surface of the polar cap toward the sea. As the polar surface slopes down toward sealevel, the wind speeds increase. Catabatic wind speeds in the Antartic can reach several hundreds of miles per hour. In the images of the Martian north polar cap we can see these same type of winds. Notice the streamers of dust moving downslope over the darker trough sides, these streamers show the laminar flow regime coming off the cap. Within the trough we see turbulent clouds of dust, kicked up at the trough base as the winds slow down and enter a chaotic flow regime. The horizontal lines in these images are due to framelet overlap and lighting conditions over the bright polar cap. Image information: VIS instrument. Latitude 84.3, Longitude 314.4 East (45.6 West). 40 meter/pixel resolution. Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.NASA Technical Reports Server (NTRS)
2004-01-01
[figure removed for brevity, see original site] This week we will be looking at five examples of laminar wind flow on the north polar cap. On Earth, gravity-driven south polar cap winds are termed 'catabatic' winds. Catabatic winds begin over the smooth expanse of the cap interior due to temperature differences between the atmosphere and the surface. Once begun, the winds sweep outward along the surface of the polar cap toward the sea. As the polar surface slopes down toward sealevel, the wind speeds increase. Catabatic wind speeds in the Antartic can reach several hundreds of miles per hour. In the images of the Martian north polar cap we can see these same type of winds. Notice the streamers of dust moving downslope over the darker trough sides, these streamers show the laminar flow regime coming off the cap. Within the trough we see turbulent clouds of dust, kicked up at the trough base as the winds slow down and enter a chaotic flow regime. The horizontal lines in these images are due to framelet overlap and lighting conditions over the bright polar cap. Image information: VIS instrument. Latitude 84.2, Longitude 57.4 East (302.6 West). 40 meter/pixel resolution. Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.NASA Astrophysics Data System (ADS)
Hermoso, J. L. Navarro; Espinosa-Rueda, Guillermo; Martinez, Noelia; Heras, Carlos; Osta, Marta
2016-05-01
The performance of parabolic trough (PT) receiver tubes (RT) has a direct impact on Solar Thermal Energy (STE) plant production. As a result, one major need of operation and maintenance (O&M) in STE plants is to monitor the state of the receiver tube as a key element in the solar field. However the lack of specific devices so far has limited the proper evaluation of operating receiver tubés thermal performance. As a consequence non-accurate approximations have been accepted until now using infrared thermal images of the glass outer tube. In order to fulfill this need, Abengoa has developed a unique portable device for evaluating the thermal performance and vacuum state of parabolic trough receiver tubes placed in the field. The novel device described in this paper, simultaneously provides the temperature of both the inner steel tube and the outer glass tube enabling a check on manufacturers specifications. The on-field evaluation of any receiver tube at any operating temperature has become possible thanks to this new measuring device. The features and usability of this new measurement system as a workable portable device in operating solar fields provide a very useful tool for all companies in the sector contributing to technology progress. The originality of the device, patent pending P201431969, is not limited to the CSP sector, also having scientific significance in the general measuring instruments field. This paper presents the work carried out to develop and validate the device, also detailing its functioning properties and including the excellent results obtained in the laboratory to determine its accuracy and standard deviation. This information was validated with data collected by O&M teams using this instrument in a commercial CSP plant. The relevance of the device has been evidenced by evaluating a wide sample of RT and the results are discussed in this paper. Finally, all the on field collected data is used to demonstrate the high impact that using this unique portable device will have on a parabolic trough solar power plant.
Evaluation of the trough-type rain gage
Irvin C. Reigner
1964-01-01
Although infrequently used, the trough-type rain gage has been described as aerodynamically the most efficient of gages (Hayes and Kittredge 1949). This applies only to the commercial semicircular eave-gutter type of trough and not to troughs rectangular in cross-section. The latter, as well as the upright cylindrical type of gage, produces greater disturbances in the...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Murphy, David J.; Horner, Robert M.; Clark, Corrie E.
Estimates of the amount of land used for a defined amount of utility-scale electricity generation in the solar power industry, referred to as solar land use energy intensity (LUEI), are important to decision makers for evaluating the environmental impact of energy technology choices. In general, solar energy tends to have a larger on-site LUEI than that of fossil fuels because the energy generated per square meter of power plant area is much lower. Unfortunately, there are few studies that quantify the off-site LUEI for utility-scale solar energy, and of those that do, they share common methodologies and data sets. Inmore » this study, we develop a new method for calculating the off-site LUEI for utility-scale solar energy for three different technologies: silicon photovoltaic (Si-PV), cadmium-telluride (CdTe) PV, and parabolic trough concentrated solar thermal. Our results indicate that the off-site LUEI is most likely 1% or less of the on-site LUEI for each technology. Although our results have some inherent uncertainties, they fall within an order of magnitude of other estimates in the literature.« less
Crustal structure and extension mode in the northwestern margin of the South China Sea
NASA Astrophysics Data System (ADS)
Gao, Jinwei; Wu, Shiguo; McIntosh, Kirk; Mi, Lijun; Liu, Zheng; Spence, George
2016-06-01
Combining multi-channel seismic reflection and gravity modeling, this study has investigated the crustal structure of the northwestern South China Sea margin. These data constrain a hyper-extended crustal area bounded by basin-bounding faults corresponding to an aborted rift below the Xisha Trough with a subparallel fossil ridge in the adjacent Northwest Sub-basin. The thinnest crust is located in the Xisha Trough, where it is remnant lower crust with a thickness of less than 3 km. Gravity modeling also revealed a hyper-extended crust across the Xisha Trough. The postrift magmatism is well developed and more active in the Xisha Trough and farther southeast than on the northwestern continental margin of the South China Sea; and the magmatic intrusion/extrusion was relatively active during the rifting of Xisha Trough and the Northwest Sub-basin. A narrow continent-ocean transition zone with a width of ˜65 km bounded seaward by a volcanic buried seamount is characterized by crustal thinning, rift depression, low gravity anomaly and the termination of the break-up unconformity seismic reflection. The aborted rift near the continental margin means that there may be no obvious detachment fault like that in the Iberia-Newfoundland type margin. The symmetric rift, extreme hyper-extended continental crust and hotter mantle materials indicate that continental crust underwent stretching phase (pure-shear deformation), thinning phase and breakup followed by onset of seafloor spreading and the mantle-lithosphere may break up before crustal-necking in the northwestern South China Sea margin.
Method and apparatus for measuring shear modulus and viscosity of a monomolecular film
Abraham, B.M.; Miyano, K.; Ketterson, J.B.
1983-10-18
Apparatus for measuring the shear modulus of a monomolecular film comprises a circular trough having inwardly sloping sides containing a liquid for supporting the monolayer on the surface thereof; a circular rotor suspended above the trough such that the lower surface of the rotor contacts the surface of the liquid, positioned such that the axis of the rotor is concentric with the axis of the trough and freely rotable about its axis; means for hydrostatically compressing the monolayer in the annular region formed between the rotor and the sides of the trough; and means for rotating the trough about its axis. Preferably, hydrostatic compression of the monolayer is achieved by removing liquid from the bottom of the trough (decreasing the surface area) while raising the trough vertically along its axis to maintain the monolayer at a constant elevation (and maintain rotor contact). In order to measure viscosity, a means for rotating the rotor about its axis is added to the apparatus.
Method and apparatus for measuring shear modulus and viscosity of a monomolecular film
Abraham, Bernard M.; Miyano, Kenjiro; Ketterson, John B.
1985-01-01
Instrument for measuring the shear modulus of a monomolecular film comprises a circular trough having inwardly sloping sides containing a liquid for supporting the monolayer on the surface thereof; a circular rotor suspended above the trough such that the lower surface of the rotor contacts the surface of the liquid, positioned such that the axis of the rotor is concentric with the axis of the trough and freely rotable about its axis; apparatus for hydrostatically compressing the monolayer in the annular region formed between the rotor and the sides of the trough; and apparatus for rotating the trough about its axis. Preferably, hydrostatic compression of the monolayer is achieved by removing liquid from the bottom of the trough (decreasing the surface area) while raising the trough vertically along its axis to maintain the monolayer at a constant elevation (and maintain rotor contact). In order to measure viscosity, a apparatus for rotating the rotor about its axis is added to the apparatus.
Concentrating Solar Power Projects - Guzmán | Concentrating Solar Power |
) Owner(s): FCC Energy (70%) Mitsui (30%) Technology: Parabolic trough Turbine Capacity: Net: 50.0 MW -Field Outlet Temp: 393°C Solar-Field Temp Difference: 100°C Power Block Turbine Capacity (Gross): 50.0 MW Turbine Capacity (Net): 50.0 MW Turbine Manufacturer: Man-Turbo Turbine Description: 5 extractions
China Report, Science and Technology, No. 197.
1983-05-13
eucalyptus trees both make excellent lumber for ship build- ing. Bark from the casuarina equisetifolia contains 13-18 percent tannic acid which can be...34 - / 2.*. 77 NOTE JPRS publications contain information primarily from foreign newspapers, periodicals and books, but also from news agency transmissions...depression zone, Hainan Island-easterly extension of Hainan Island-Dongsha continental slope uplift zone, northern Xisha Islands faulted trough and Zhongsha
Difference of the seismic structure between the Hyuga-nada and the Nankai seismogenic segments
NASA Astrophysics Data System (ADS)
Yamamoto, Y.; Obana, K.; Takahashi, T.; Nakanishi, A.; Kodaira, S.; Kaneda, Y.
2010-12-01
In the Nankai Trough, three major seismogenic zones of megathrust earthquake exist (Tokai, Tonankai and Nankai earthquake regions). The Hyuga-nada region was distinguished from these seismogenic zones because of the lack of megathrust earthquake. In the Hyuga-nada region, interplate earthquakes of M~7 occur repeatedly at intervals of about 20 years whereas no megathrust (M > 8) earthquakes had been recognized up to now. However, recent studies show the possibility of simultaneous rupture of the Tokai, Tonankai, Nankai and Hyuga-nada segments was also pointed out [e.g., Hori et al., 2009 AOGS]. To understand the possibility of seismic linkage of Nankai and Hyuga-nada segments, Japan Agency for Marine-Earth Science and Technology has been carried out a wide-angle active source survey and local seismic observation in the western end of the Nankai seismogenic zone, as a part of Research concerning Interaction Between the Tokai, Tonankai and Nankai Earthquakes' funded by Ministry of Education, Culture, Sports, Science and Technology, Japan. Nakanishi et al [2009, AGU] showed that subducting Philippine Sea Plate can be divided into three zones and there is the zone of the thin oceanic crust of the subducting Philippine Sea Plate between Nankai segment and Kyushu-Palau Ridge segment by analyzing of the active source survey. Deep structure of the subducting slab is also important to consider the possibility of the seismic linkage and the location of the boundary among three zones described above. To obtain the deep seismic image, we performed a three-dimensional seismic tomography using the local seismic data recorded on 158 ocean bottom seismographs and 105 land seismic stations. From these data, we could detect 1141 earthquakes in the Hyuga-nada region. From the result of hypocenter relocation, microseismicity near the trough axis is active on the western part of the ‘thin oceanic crust’, whereas inactive on the eastern part. Besides, velocity structure of the uppermost part of the subducting slab mantle shows spatial heterogeneities. In the thin oceanic crust zone, high velocity slab mantle is imaged from near the trough to coastline. On the other hands, there is low velocity zone in the slab mantle near the trough axis in the Kyusyu-Palau Ridge segment. This low velocity zone may be related to the location of the eastern end of subducted Kyusyu-Palau Ridge.
Cordero-Coma, Miguel; Calleja-Antolín, Sara; Garzo-García, Irene; Nuñez-Garnés, Ana M; Álvarez-Castro, Carolina; Franco-Benito, Manuel; Ruiz de Morales, Jose G
2016-12-01
To evaluate the rate of immunogenicity induced by adalimumab and its relationship with drug serum levels and clinical responses in patients with noninfectious uveitis. Prospective observational study. Consecutive patients from 1 referral center who initiated treatment with adalimumab for active noninfectious uveitis resistant to conventional therapy. All patients received 40 mg adalimumab every other week. Patients were evaluated clinically and immunologically before and after 4, 8, and 24 weeks of treatment. Clinical evaluation included assessment of changes in visual acuity, degree of inflammation in the anterior chamber and vitreous cavity, central macular thickness, and retinal angiographic leakage. Immunologic evaluation included assessment of serum trough adalimumab and antibodies against adalimumab (AAA) levels and class II HLA typing. Twenty-five patients were enrolled. Overall, 18 of 25 patients (72%) showed a favorable clinical response to adalimumab therapy. Eleven patients (44%) achieved a complete response and 7 (28%) achieved a partial response. However, 7 of 25 patients (28%) were considered nonresponders. Median trough adalimumab serum levels were higher in responders than in nonresponders (P < 0.001). We observed AAA positivity (AAA+) at least 1 time point in 8 of 25 patients (32%), including 4 with transitory AAA and 4 with permanent AAA. In all patients with permanent AAA+, trough adalimumab levels became undetectable (P < 0.001). However, in patients who demonstrated transitory AAA+, no correlation was observed between AAA titers and adalimumab trough levels (P = 0.2).Concomitant immunosuppression did not show any protective effect on adalimumab immunogenicity in our cohort. An association between the presence of AAA+ and a worse uveitis outcome was observed only in patients with permanent AAA+, which correlated with undetectable adalimumab trough levels (P = 0.014). Treatment of noninfectious uveitis with adalimumab is associated with high rates of favorable clinical response. Overall, adalimumab trough levels were higher in responder patients. Development of permanent AAA was associated with undetectable trough adalimumab levels and worse uveitis outcome. Immunogenicity was more common in patients in whom uveitis was associated with a systemic disease and was not influenced by concomitant immunosuppressors. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.
Concentrating Solar Power Projects in China | Concentrating Solar Power |
Delingha 50MW Thermal Oil Parabolic Trough project Gansu Akesai 50MW Molten Salt Trough project Golden Tower 100MW Molten Salt project Golmud Gulang 100MW Thermal Oil Parabolic Trough project Hami 50 MW CSP Yumen 50MW Thermal Oil Trough project Shangyi 50MW DSG Tower CSP project SunCan Dunhuang 10 MW Phase I
Tkachuk, Stacey; Collins, Kyle; Ensom, Mary H H
2018-04-01
In adults, the area under the concentration-time curve (AUC) divided by the minimum inhibitory concentration (MIC) is associated with better clinical and bacteriological response to vancomycin in patients with methicillin-resistant Staphylococcus aureus who achieve target AUC/MIC ≥ 400. This target is often extrapolated to pediatric patients despite the lack of similar evidence. The impracticalities of calculating the AUC in practice means vancomycin trough concentrations are used to predict the AUC/MIC. This review aimed to determine the relationship between vancomycin trough concentrations and AUC/MIC in pediatric patients. We searched the MEDLINE and Embase databases, the Cochrane Database of Systematic Reviews, and the Cochrane Central Register of Controlled Trials using the medical subject heading (MeSH) terms vancomycin and AUC and pediatric* or paediatric*. Articles were included if they were published in English and reported a relationship between vancomycin trough concentrations and AUC/MIC. Of 122 articles retrieved, 11 met the inclusion criteria. One trial reported a relationship between vancomycin trough concentrations, AUC/MIC, and clinical outcomes but was likely underpowered. Five studies found troughs 6-10 mg/l were sufficient to attain an AUC/MIC > 400 in most general hospitalized pediatric patients. One study in patients undergoing cardiothoracic surgery found a trough of 18.4 mg/l achieved an AUC/MIC > 400. Two oncology studies reported troughs ≥ 15 mg/l likely attained an AUC/MIC ≥ 400. In critical care patients: one study found a trough of 9 mg/l did not attain the AUC/MIC target; another found 7 mg/l corresponded to an AUC/MIC of 400. Potential vancomycin targets varied based on the population studied but, for general hospitalized pediatric patients, troughs of 6-10 mg/l are likely sufficient to achieve AUC/MIC ≥ 400. For MIC ≥ 2 mg/l, higher troughs are likely necessary to achieve an AUC/MIC ≥ 400. More research is needed to determine the relationships between vancomycin trough concentrations, AUC/MIC, and clinical outcomes.
Vancomycin AUC/MIC and Corresponding Troughs in a Pediatric Population
Lardieri, Allison B.; Heil, Emily L.; Morgan, Jill A.
2017-01-01
OBJECTIVES Adult guidelines suggest an area under the curve/minimum inhibitory concentration (AUC/MIC) > 400 corresponds to a vancomycin trough serum concentration of 15 to 20 mg/L for methicillin-resistant Staphylococcus aureus infections, but obtaining these troughs in children are difficult. The primary objective of this study was to assess the likelihood that 15 mg/kg of vancomycin every 6 hours in a child achieves an AUC/MIC > 400. METHODS This retrospective chart review included pediatric patients >2 months to <18 years with a positive S aureus blood culture and documented MIC who received at least two doses of vancomycin with corresponding trough. Patients were divided into two groups: group 1 initially receiving ≥15 mg/kg every 6 hours, and group 2 initially receiving any other dosing ranges or intervals. AUCs were calculated four times using three pharmacokinetic methods. RESULTS A total of 36 patients with 99 vancomycin trough serum concentrations were assessed. Baseline characteristics were similar between groups. For troughs in group 1 (n = 55), the probability of achieving an AUC/MIC > 400 ranged from 16.4% to 90.9% with a median trough concentration of 11.4 mg/L, while in group 2 (n = 44) the probability of achieving AUC/MIC > 400 ranged from 15.9% to 54.5% with mean trough concentration of 9.2 mg/L. The AUC/MICs were not similar between the different pharmacokinetic methods used; however, a trapezoidal equation (Method A) yielded the highest correlation coefficient (r2 = 0.59). When dosing every 6 hours, an AUC/MIC of 400 correlated to a trough serum concentration of 11 mg/L. CONCLUSIONS The probability of achieving an AUC/MIC > 400 using only a trough serum concentration and an MIC with patients receiving 15 mg/kg every 6 hours is variable based on the method used to calculate the AUC. An AUC/MIC of 400 in children correlated to a trough concentration of 11 mg/L using a trapezoidal Method to calculate AUC. PMID:28337080
Vancomycin AUC/MIC and Corresponding Troughs in a Pediatric Population.
Kishk, Omayma A; Lardieri, Allison B; Heil, Emily L; Morgan, Jill A
2017-01-01
Adult guidelines suggest an area under the curve/minimum inhibitory concentration (AUC/MIC) > 400 corresponds to a vancomycin trough serum concentration of 15 to 20 mg/L for methicillin-resistant Staphylococcus aureus infections, but obtaining these troughs in children are difficult. The primary objective of this study was to assess the likelihood that 15 mg/kg of vancomycin every 6 hours in a child achieves an AUC/MIC > 400. This retrospective chart review included pediatric patients >2 months to <18 years with a positive S aureus blood culture and documented MIC who received at least two doses of vancomycin with corresponding trough. Patients were divided into two groups: group 1 initially receiving ≥15 mg/kg every 6 hours, and group 2 initially receiving any other dosing ranges or intervals. AUCs were calculated four times using three pharmacokinetic methods. A total of 36 patients with 99 vancomycin trough serum concentrations were assessed. Baseline characteristics were similar between groups. For troughs in group 1 (n = 55), the probability of achieving an AUC/MIC > 400 ranged from 16.4% to 90.9% with a median trough concentration of 11.4 mg/L, while in group 2 (n = 44) the probability of achieving AUC/MIC > 400 ranged from 15.9% to 54.5% with mean trough concentration of 9.2 mg/L. The AUC/MICs were not similar between the different pharmacokinetic methods used; however, a trapezoidal equation (Method A) yielded the highest correlation coefficient (r 2 = 0.59). When dosing every 6 hours, an AUC/MIC of 400 correlated to a trough serum concentration of 11 mg/L. The probability of achieving an AUC/MIC > 400 using only a trough serum concentration and an MIC with patients receiving 15 mg/kg every 6 hours is variable based on the method used to calculate the AUC. An AUC/MIC of 400 in children correlated to a trough concentration of 11 mg/L using a trapezoidal Method to calculate AUC.
Origin and late quaternary tectonism of a western Canadian continental shelf trough
NASA Astrophysics Data System (ADS)
Moslow, Thomas F.; Luternauer, John L.; Rohr, Kristin
1991-08-01
Analyses of high resolution and multi-channel seismic profiles from the central continental shelf of western Canada ascribe a late Quaternary glacial origin to large-scale troughs. Along the margins of Moresby Trough, one of three large-scale cross-shelf bathymetric depressions in Queen Charlotte Sound, seismic profiles within Quaternary sediments show a divergence of reflectors, thickening and folding of seismic units, and concavity of reflectors suggestive of drag. Compactional subsidence, growth faulting, and compaction faulting are also observed. Fault traces commonly terminate below the seabed. Deformation of Quaternary sediments due to faulting is plastic in nature and maximum offset of reflectors is 2.5 m. The observed Quaternary deformation appears to be a product of rapid deposition, loading and subsidence of late Quaternary sediment, which is unrelated to seismic activity. In addition, Quaternary faulting was probably activated by post-glacial loading and isostatic rebound of consolidated Tertiary strata along the margins of continental shelf troughs. The presence of mass movement (slump or debris flow) deposits overlying lithified Tertiary strata along the flanks of Moresby Trough provides the only evidence of seismic activity in the study area. The lack of a mud drape over these deposits implies a late Holocene age for the timing of their emplacement. The Quaternary troughs are incised into Tertiary-aged sedimentary fill of the Queen Charlotte basin. Previous workers had interpreted seafloor escarpments paralleling the trough margins to indicate that the location of Moresby Trough was controlled by renewed or continued activity on Tertiary-aged faults. A multi-channel seismic line across Moresby Trough shows that such an escarpment on the seafloor does not correlate to faults either in the Tertiary basin fill or the underlying basement. Tertiary reflectors are continuous underneath Moresby Trough; the seafloor escarpment is an erosional feature and was not created by reactivation of Tertiary structures. Trough erosion and subsequent fill (up to 175 m thick) are entirely of Quaternary age.
Bond, Ashley; Dodd, Susanna; Fisher, Gareth; Skouras, Thomas; Subramanian, Sreedhar
2017-02-01
Combination therapy with infliximab and immunomodulators is superior to monotherapy, resulting in better outcomes and higher trough levels of infliximab. The role of concurrent immunomodulatory therapy on adalimumab trough levels has not been adequately investigated. We evaluated the impact of concomitant immunomodulation on adalimumab trough levels in patients on scheduled maintenance therapy. We conducted a prospective observational, cross-sectional study of all inflammatory bowel disease patients on maintenance therapy who had adalimumab trough levels measured between January 2013 and January 2016. Drug level and anti-drug antibody measurements were performed on sera using a solid phase assay. Pairwise comparison of means was used to compare trough levels in patients with and without concomitant immune modulator therapy. In total, 79 patients were included. Twenty-three patients (29.1%) were on weekly dosing whereas 56 (70.9%) were on alternate weeks. Median adalimumab trough levels were comparable in patients with and without clinical remission (6.8 μg/ml (IQR 5.6-8.1) versus 6.7 μg/ml (IQR 3.9-8.1), respectively. Patients with an elevated faecal calprotectin >250 μg/g had lower adalimumab trough levels (median 6.7, IQR 3.9-8) compared to patients with faecal calprotectin <250 μg/g (median 7.7, IQR 6.1-8.1) though this did not achieve statistical significance (p = .062). Median adalimumab trough levels among patients on concurrent immunomodulators was 7.2 μg/ml (IQR 5.7-8.1) compared to those not on concurrent immunomodulator, 6.1 μg/ml (IQR 2.7-7.7, p = .0297). Adalimumab trough levels were significantly higher in patients on concurrent immunomodulators during maintenance therapy. There was a trend towards a lower adalimumab trough level in patients with elevated calprotectin.
Dong, Mo-Han; Wang, Jing-Wen; Wu, Yin; Chen, Bei-Yu; Yu, Min; Wen, Ai-Dong
2015-08-01
To identify specific risk factors of vancomycin-induced nephrotoxicity in China, as the relationship between vancomycin therapy (dosing and trough concentration monitoring) and nephrotoxicity has been the subject of critical debate. The cases of 90 critically ill patients who received vancomycin therapy in Xijing Hospital in the northwest of China between March 2014 and January 2015 were reviewed retrospectively. Vancomycin dosing, blood serum trough concentration, and other independent risk factors associated with nephrotoxicity were evaluated in a multivariable model. Among the 90 critically ill patients, 59 were males; mean age was 46.3 years. The indications for vancomycin use were methicillin-resistant Staphylococcus aureus-associated pneumonia, central nervous system infection, and bacteremia. Clinical pharmacists prescribed weight-based dosing, ranging from 20 to 45mg/kg/day. Fourteen (15.6%) patients developed nephrotoxicity, with serum creatinine elevated significantly from a mean (standard deviation) of 90.0 (18.8) μmol/l to 133.8 (63.2) μmol/l (p = 0.015). It was found that those with a vancomycin dosage >38mg/kg/day (50.0% vs. 11.3%, p = 0.004) and a vancomycin serum trough concentration >20mg/l (57.1% vs. 12.0%, p = 0.01) were more likely to develop nephrotoxicity. The data from this study indicate that a vancomycin dosage >38mg/kg/day and a serum trough level >20mg/l are both independent factors associated with the development of nephrotoxicity, suggesting that renal function should be monitored closely during vancomycin treatment. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
Pc-5 wave power in the plasmasphere and trough: CRRES observations
NASA Astrophysics Data System (ADS)
Hartinger, M.; Moldwin, M.; Angelopoulos, V.; Takahashi, K.; Singer, H. J.; Anderson, R. R.
2009-12-01
The CRRES (Combined Release and Radiation Effects Satellite) mission provides an opportunity to study the distribution of MHD wave power in the inner magnetosphere both inside the high-density plasmasphere and in the low-density trough. We present a statistical survey of Pc-5 wave power using CRRES magnetometer and plasma wave data separated into plasmasphere and trough intervals. Using a database of plasmapause crossings, we examined differences in power spectral density between the plasmasphere and trough regions. We found significant differences between the plasmasphere and trough in the radial profiles of Pc-5 wave power. On average, wave power was higher in the trough, but the difference in power depended on magnetic local time. Our study shows that determining the plasmapause location is important for understanding and modeling the MHD wave environment in the Pc-5 frequency band.
NASA Technical Reports Server (NTRS)
Taylor, H. A., Jr.
1972-01-01
A distinct feature of the ion composition results from the OGO-2, 4 and 6 satellites is the light ion trough, wherein the mid-latitude concentrations of H+ and He+ decrease sharply with latitude. In contrast to the 'main trough' in electron density observed primarily as a nightside phenomenon, the light ion trough persists during both day and night. For daytime winter hemisphere conditions and for all seasons during night, the mid-latitude light ion concentration decrease is a pronounced feature. In the dayside summer and equinox hemispheres, the rate of light ion decrease with latitude is comparatively gradual, and the trough boundary is less well defined, particularly for quiet magnetic conditions. In response to magnetic storms, the light ion trough minimum moves equatorward, and deepens, consistent with earlier evidence of the contraction of the plasmasphere in response to storm time enhancements in magnetospheric plasma convection.
NASA Astrophysics Data System (ADS)
Fink, A. H.; Pohle, S.
2009-04-01
Tropical Extra-tropical Interactions (TEIs) are often observed in association with an upper-level subtropical trough that penetrates into the tropics and, therefore, interacts with the tropical circulation. As a visible sign, a mid- to upper-level cloud band at the eastern flank of the trough and its related Subtropical Jet, named Tropical Plume (TP), is identifiable in infrared satellite imagery. McGuirk et al. (1987) gave a definition of Tropical Plumes and described the cloud bands as a northern hemisphere winter time phenomena. Previous studies identified TPs throughout the year with being rare in the June-mid- September period. Results of convection dynamics influenced/caused by TEIs during a pre-monsoon season event between 19 and 30 May 2006 will be presented. This case is characterized by two different investigation regions affected by TEI: During the first half of the event high precipitation amounts south-east of the cloud band over Burkina Faso, Benin, Togo, and Ivory Coast are observed caused by thermal forcing and dynamical maintenance by trough related good upper-level outflow conditions due to ageostrophic acceleration towards the trough and low inertial stability, or even inertial instability. This presentation is focused on the second half of this TEI event, which is characterized by the development of a pronounced heat low (HL) south-east of the upper-level trough over tropical West Africa, followed by convection south-east of the low pressure centre. A modified form of the pressure tendency equation (PTE) used by Knippertz and Fink (2008) is a diagnostic tool to investigate, which processes cause pressure drop near the Mali-Burkina Faso border by using both, the operational ECMWF Analysis and the AMMA EU re-analysis. The latter contains additionally the diabatic heating tendencies. Therefore, all terms of the PTE were calculated and will be discussed.
Stoessel, Andrew M; Hale, Cory M; Seabury, Robert W; Miller, Christopher D; Steele, Jeffrey M
2018-01-01
This study aimed to assess the impact of area under the curve (AUC)-based vancomycin monitoring on pharmacist-initiated dose adjustments after transitioning from a trough-only to an AUC-based monitoring method at our institution. A retrospective cohort study of patients treated with vancomycin for complicated methicillin-resistant Staphylococcus aureus (MRSA) infection between November 2013 and December 2016 was conducted. The frequency of pharmacist-initiated dose adjustments was assessed for patients monitored via trough-only and AUC-based approaches for trough ranges: 10 to 14.9 mg/L and 15 to 20 mg/L. Fifty patients were included: 36 in the trough-based monitoring and 14 in the AUC-based-monitoring group. The vancomycin dose was increased in 71.4% of patients when troughs were 10 to 14.9 mg/L when a trough-only approach was used and in only 25% of patients when using AUC estimation ( P = .048). In the AUC group, the dose was increased only when AUC/minimum inhibitory concentration (MIC) <400; unchanged regimens had an estimated AUC/MIC ≥400. The AUC-based monitoring did not significantly increase the frequency of dose reductions when trough concentrations were 15 to 20 mg/L (AUC: 33.3% vs trough: 4.6%; P = .107). The AUC-based monitoring resulted in fewer patients with dose adjustments when trough levels were 10 to 14.9 mg/L. The AUC-based monitoring has the potential to reduce unnecessary vancomycin exposure and warrants further investigation.
Obara, Vitor Yuzo; Zacas, Carolina Petrus; Carrilho, Claudia Maria Dantas de Maio; Delfino, Vinicius Daher Alvares
2016-01-01
This study aimed to assess whether currently used dosages of vancomycin for treatment of serious gram-positive bacterial infections in intensive care unit patients provided initial therapeutic vancomycin trough levels and to examine possible factors associated with the presence of adequate initial vancomycin trough levels in these patients. A prospective descriptive study with convenience sampling was performed. Nursing note and medical record data were collected from September 2013 to July 2014 for patients who met inclusion criteria. Eighty-three patients were included. Initial vancomycin trough levels were obtained immediately before vancomycin fourth dose. Acute kidney injury was defined as an increase of at least 0.3mg/dL in serum creatinine within 48 hours. Considering vancomycin trough levels recommended for serious gram-positive infection treatment (15 - 20µg/mL), patients were categorized as presenting with low, adequate, and high vancomycin trough levels (35 [42.2%], 18 [21.7%], and 30 [36.1%] patients, respectively). Acute kidney injury patients had significantly greater vancomycin trough levels (p = 0.0055, with significance for a trend, p = 0.0023). Surprisingly, more than 40% of the patients did not reach an effective initial vancomycin trough level. Studies on pharmacokinetic and dosage regimens of vancomycin in intensive care unit patients are necessary to circumvent this high proportion of failures to obtain adequate initial vancomycin trough levels. Vancomycin use without trough serum level monitoring in critically ill patients should be discouraged.
NASA Astrophysics Data System (ADS)
Newton, Andrew; Huuse, Mads
2016-04-01
Compared to other glaciated margins such as offshore mid-Norway and Svalbard, the Greenland continental shelf has, until recently, been the subject of only a limited amount of academic and industry research. This has been mainly due to the difficulty and expense of obtaining data in such harsh and operationally complex settings. Climate amelioration and technological advance has, particularly in recent years, allowed both academics and industry to substantially increase data collection across the many glaciated continental shelves in the Northern Hemisphere. Baffin Bay has been one of the primary regions of interest for the hydrocarbon industry which has sought to operate in the frontier basins offshore Greenland. As a result of these industry operations, a large database of geophysical and geological data has been collected. Some of this data has been made available to glacial scientists and provides a unique opportunity to investigate the seafloor geomorphology for regions where the majority of previous work has been hypothetical rather than grounded in geological evidence. In the work presented here we present a landform record offshore NW Greenland in the Melville Bay cross-shelf trough. This is one of the largest troughs on the entire Greenland shelf and measures up to 140 km in width. Shallow-marine cores collected in the coastal part of the trough show bedrock of Miocene age and indicate that a significant cover has likely been removed from the shelf by ice streams operating through the Late Cenozoic. This material has then been deposited at the shelf edge as a trough mouth fan. Using multibeam and seismic reflection data a large number of glacial landforms are observed and mapped in the trough. These include mega-scale glacial lineations, grounding-zone wedges, iceberg scours, and iceberg grounding pits. These landforms are used to reconstruct the ice dynamics of the Melville Bugt Ice Stream at the last glacial maximum and during its deglaciation. The observed grounding-zone wedges suggest that initial retreat was punctuated with two still-stands of long enough duration to accumulate material at the grounding zone. As the ice sheet decayed further, a rapid retreat of over 30 km occurred before the grounding line margin was stabilised again. Understanding the nonlinear rate of grounding-line retreat such as that presented here is crucial for the future modelling of not just the evolution of the Greenland Ice Sheet but also those elsewhere.
CSPonD demonstrative project: Start-up process of a 25 kW prototype
NASA Astrophysics Data System (ADS)
Gil, Antoni; Grange, Benjamin; Perez, Victor G.; Tetreault-Friend, Melanie; Codd, Daniel S.; Calvet, Nicolas; Slocum, Alexander S.
2017-06-01
The current concept of commercial concentrated solar power (CSP) plants, based on the concept of a solar field, receiver, storage and power block, experienced significant growth in the past decades. The power block is the most well know part of the plant, while solar field depends on the receiver technology. The dominant receiver technologies are parabolic troughs and central towers. Most thermal energy storage (TES) relies on two tanks of molten salts, one hot and one cold serviced by pumps and piping systems. In spite of the technical development level achieved by these systems, efficiency is limited, mainly caused by thermal losses in piping, parasitic losses due to electric tracing and pumping and receiver limitations. In order to mitigate the these issues, a new concept called Concentrated Solar Power on Demand (CSPonD), was developed, consisting of a direct absorption Solar Salt CSP receiver which simultaneously acts as TES tank. Currently, in the frame of the flagship collaborative project between the Masdar Institute (UAE) and the Massachusetts Institute of Technology (USA) a 25 kW demonstrative prototype is in its final building phase at the Masdar Institute Solar Platform. The present paper, explains the demonstration prototype based on the CSPonD concept, with emphasis on the planned start-up process for the facility.
Fabrication of trough-shaped solar collectors
Schertz, William W.
1978-01-01
There is provided a radiant energy concentration and collection device formed of a one-piece thin-walled plastic substrate including a plurality of nonimaging troughs with certain metallized surfaces of the substrate serving as reflective side walls for each trough. The one-piece plastic substrate is provided with a seating surface at the bottom of each trough which conforms to the shape of an energy receiver to be seated therein.
Bunnapradist, S; Ciechanowski, K; West-Thielke, P; Mulgaonkar, S; Rostaing, L; Vasudev, B; Budde, K
2013-03-01
Phase III noninferiority trial examining efficacy and safety of converting stable renal transplant recipients from twice-daily tacrolimus to a novel extended-release once-daily tacrolimus formulation (LCPT) with a controlled agglomeration technology. Controls maintained tacrolimus twice daily. The primary efficacy endpoint was proportion of patients with efficacy failures (death, graft failure, locally read biopsy-proven acute rejection [BPAR], or loss to follow-up) within 12 months. Starting LCPT dose was 30% lower (15% for blacks) than preconversion tacrolimus dose; target trough levels were 4-15 ng/mL. A total of 326 patients were randomized; the mITT population (n = 162 each group) was similar demographically in the two groups. Mean daily dose of LCPT was significantly (p < 0.0001) lower than preconversion tacrolimus dose at each visit; mean trough levels between groups were similar. There were four efficacy failures in each group; safety outcomes were similar between groups. Frequency of premature study drug discontinuation was LCPT: 12% versus tacrolimus twice daily: 5% (p = 0.028). LCPT demonstrated noninferiority to tacrolimus twice daily in efficacy failure rates. LCPT may offer a safe and effective alternative for converting patients to a once-daily formulation. Compared to currently available tacrolimus formulation, LCPT requires lower doses to achieve target trough levels. © Copyright 2012 The American Society of Transplantation and the American Society of Transplant Surgeons.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mehos, Mark; Turchi, Craig; Jorgensen, Jennie
2016-03-01
Since the SunShot Vision Study (DOE 2012) was published, global deployment of concentrating solar power (CSP) has increased threefold to nearly 4,500 MW, with a similar threefold increase in operational capacity to 1,650 MW within the United States. Growth in U.S. CSP capacity has primarily been driven by policy support at the state and federal levels. State-driven renewable portfolio standards (RPSs), combined with a 30% federal investment tax credit (ITC) and federal loan guarantees, provided the opportunity for CSP developers to kick-start construction of CSP plants throughout the Southwest. Figure ES-1 demonstrates that deployment and private- and public-sector research andmore » development have led to dramatic cost reductions that have placed CSP well on the path to reaching the U.S. Department of Energy’s SunShot Initiative goal of 6 cents/kWh by 2020. In comparing the estimated capital costs from the SunShot Vision Study and the current analysis, we find that parabolic trough solar-field costs have fallen more rapidly than predicted, although the drop in solar-field costs was offset by the additional costs of moving from a wet-cooled power block in 2010 to a more expensive dry-cooled power block in 2015. The predicted 2015 decline in tower costs was in line with expectations, primarily driven by reduced heliostat costs. Figure ES-1 shows the reduction in levelized cost of electricity (LCOE) for both parabolic trough and tower systems, in addition to the projected 2020 SunShot target.« less
Designing Better Water Troughs: Does Trough Color Influence Dairy Cows' Preference?
Lemos Teixeira, Dayane; Hötzel, Maria José; Pinheiro Machado Filho, Luiz Carlos; Cazale, José Daniel; Enríquez-Hidalgo, Daniel
2017-01-01
Eighteen lactating dairy cows were used to elucidate their preference for green, grey, or red troughs. The herd was managed under a rotational grazing system with ad-libitum access to water until 11:30 h. For 9 days, all cows were tested individually following the afternoon milking. Cows drank similar quantities, spent a similar amount of time drinking, and took a similar number of sips from the 3 trough colors (p > .05). In 75% of the tests, cows drank more than 95% of the test period from the same trough. Within this time, the percentage of choices did not differ among colors (33.3% green, 39.0% grey, and 27.7% red). When they chose the red trough, cows spent less time drinking (p ≤ .05) and tended to take fewer sips (p = .07), which could suggest a partial aversion to this color. Suboptimal water trough design may have long-term negative effects on both the production and welfare of dairy cattle; however, the results suggest that color does not play a major role in the drinking behavior of dairy cows.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Binotti, M.; Zhu, G.; Gray, A.
An analytical approach, as an extension of one newly developed method -- First-principle OPTical Intercept Calculation (FirstOPTIC) -- is proposed to treat the geometrical impact of three-dimensional (3-D) effects on parabolic trough optical performance. The mathematical steps of this analytical approach are presented and implemented numerically as part of the suite of FirstOPTIC code. In addition, the new code has been carefully validated against ray-tracing simulation results and available numerical solutions. This new analytical approach to treating 3-D effects will facilitate further understanding and analysis of the optical performance of trough collectors as a function of incidence angle.
New sidescan sonar and gravity evidence that the Nova-Canton Trough is a fracture zone
NASA Astrophysics Data System (ADS)
Joseph, Devorah; Taylor, Brian; Shor, Alexander N.
1992-05-01
A 1990 sidescan sonar survey in the eastern region of the Nova-Canton Trough mapped 138°-striking abyssal-hill fabric trending into 70°-striking trough structures. The location and angle of intersection of the abyssal hills with the eastern Nova-Canton Trough effectively disprove a spreading-center origin of this feature. Free-air gravity anomalies derived from satellite altimetry data show continuity, across the Line Islands, of the Nova-Canton Trough with the Clipperton Fracture Zone. The Canton-Clipperton trend is copolar, about a pole at 30°S, 152°W, with other coeval Pacific-Farallon fracture-zone segments, from the Pau to Marquesas fracture zones. This copolarity leads us to postulate a Pacific-Farallon spreading pattern for the magnetic quiet zone region north and east of the Manihiki Plateau, with the Nova-Canton Trough originating as a transform fault in this system.
Topography of Valles Marineris: Implications for erosional and structural history
NASA Technical Reports Server (NTRS)
Lucchitta, B. K.; Isbell, N. K.; Howington-Kraus, A.
1994-01-01
Compilation of a simplified geologic/geomorphic map onto digital terrain models of the Valles Marineris permitted an evaluation of elevations in the vicinity of the troughs and the calculation of depth of troughs below surrounding plateaus, thickness of deposits inside the troughs, volumes of void spaces above geologic/geomorphic units, and volumes of deposits. The central troughs north Ophir, north and central Candor, and north Melas Chasmata lie as much as 11 km below the adjacent plateaus. In Ophir and Candor chasmata, interior layered deposits reach 8 km in elevation. If the deposits are lacustrine and if all troughs were interconnected, lake waters standing 8 km high would have spilled out of Coprates Chasma onto the surrounding plateaus having surface elevations of only 4-5 km. On the other hand, the troughs may not have been interconnected at the time of interior-deposit emplacement; they may have formed isolated ancestral basins. The existence of such basins is supported by independent structural and stratigraphic evidence. The ancestral basins may have eventually merged, perhaps through renewed faulting, to form northern subsidiary troughs in Ophir and Candor Chasmata and the Coprates/north Melas/Ius graben system. The peripheral troughs are only 2-5 km deep, shallower than the central troughs. Chaotic terrain is seen in the peripheral troughs near a common contour level of about 4 km on the adjacent plateaus, which supports the idea of release of water under artesian pressure from confined aquifers. The layered deposits in the peripheral troughs may have formed in isolated depressions that harbored lakes and predated the formation of the deep outflow channels. (If these layered deposits are of volcanic origin, they may have been emplaced beneath ice in the manner of table mountains.) Areal and volumetric computations show that erosion widened the troughs by about one-third and that deposits occupy one-sixth of the interior space. Even though the volume eroded is larger than the volume deposited, topographic and geologic considerations imply that material eroded from trough walls was probably part of the interior layered deposits but not their sole source. Additional material may have come from subterranean piping, from reworking of local disintegration products on the floors, such as chaotic materials, or from eolian influx. But overall it is likely that the additional material is volcanic and that it forms mostly the upper, more diversely bedded layers of the interior deposits.
Contreiras, Claire; Legal, Michael; Lau, Tim T Y; Thalakada, Rosanne; Shalansky, Stephen; Ensom, Mary H H
2014-01-01
Background: In the past, impurities in vancomycin formulations were thought to contribute to nephrotoxicity. In contrast, when current, purer formulations are dosed at conventional trough levels (i.e., 5–15 mg/L), the incidence of nephrotoxicity is relatively low. Recent guidelines have recommended targeting higher vancomycin trough levels in treatment of complicated methicillin-resistant Staphylococcus aureus infections. Dosing based on these higher trough levels may be associated with nephrotoxicity, so the potential risk factors for vancomycin-associated nephrotoxicity require clearer definition. Objectives: To determine the occurrence of nephrotoxicity in patients receiving more than 7 days of vancomycin therapy with high trough levels (15–20 mg/L) and to identify and evaluate specific risk factors related to development of vancomycin-associated nephrotoxicity (i.e., serum creatinine ≥ 44.2 μmol/L or increase ≥ 50% [i.e., ≥ 26.2 μmol/L] from baseline on 2 consecutive days). Methods: Health care records were reviewed for patients seen at 2 major teaching hospitals between January 2008 and March 2011. Patients who had attained high trough levels of vancomycin were screened for eligibility. Patients with unstable renal function, those undergoing hemodialysis, and those for whom dosage and/or sampling times were unclear were excluded. Univariate and multivariate analyses were performed to identify risk factors associated with nephrotoxicity. Univariate variables with p < 0.1 were included in the logistic regression model. Results: Of the 176 patients with high trough levels included in the analysis, 24 (14%) experienced nephrotoxicity. In univariate analysis, admission to a general medicine unit (the setting of care for 16 [67%] of the 24 patients with nephrotoxicity) and extended duration of vancomycin treatment were identified as risk factors for nephrotoxicity (p < 0.1). Other risk factors included gastrointestinal comorbidity (p = 0.056), malignancy (p = 0.044), and febrile neutropenia (p = 0.032). Multivariate analysis identified treatment on general medicine units and treatment courses longer than 7 days as independent predictors of vancomycin-associated nephrotoxicity. Conclusion: Patients being treated on general medicine units and those receiving vancomycin for more than 7 days had an increased likelihood of experiencing nephrotoxicity. The increased risk for patients on general medicine units is likely multifactorial. The relationship between treatment duration and risk of nephrotoxicity appeared to be linear. When using extended-duration, high-trough vancomycin therapy, clinicians should be vigilant in monitoring for nephrotoxicity. PMID:24799722
NASA Technical Reports Server (NTRS)
2006-01-01
9 June 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small portion of a dust-covered plain directly north of Labyrinthus Noctis which is cut by three linear troughs. The two long troughs running diagonally from the lower left (southwest) to the upper right (northeast) are connected by a third, shorter trough. Boulders derived from erosion of layered rock in the trough walls are seen perched on the sloping sidewalls and resting on the trough floors among giant windblown ripples. Location near: 0.2oN, 105.0oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Northern SpringBedrock morphology reveals drainage network in northeast Baffin Bay
NASA Astrophysics Data System (ADS)
Slabon, Patricia; Dorschel, Boris; Jokat, Wilfried; Freire, Francis
2018-02-01
A subglacial drainage network underneath the paleo-ice sheet off West Greenland is revealed by a new compilation of high-resolution bathymetry data from Melville Bay, northeast Baffin Bay. This drainage network is an indicator for ice streaming and subglacial meltwater flow toward the outer shelf. Repeated ice sheet advances and retreats across the crystalline basement together with subglacial meltwater drainage had their impact in eroding overdeepened troughs along ice stream pathways. These overdeepenings indicate the location of a former ice sheet margin. The troughs inherit characteristics of glacial and subglacial meltwater erosion. Most of the troughs follow tectonic weakness zones such as faults and fractures in the crystalline bedrock. Many of these tectonic features correspond with the orientations of major fault axes in the Baffin Bay region. The troughs extend from the present (sub) glacial fjord systems at the Greenland coast and parallel modern outlet-glacier pathways. The fast flowing paleo-ice streams were likely accelerated from the meltwater flow as indicated by glacial landforms within and along the troughs. The ice streams flowed along narrow tributary troughs and merged to form large paleo-ice streams bedded in the major cross-shelf troughs of Melville Bay. Apart from the troughs, a rough seabed topography characterises the bedrock, and we see a sharp geomorphic transition where ice flowed onto sedimentary rock and deposits.
Seasonal variation and solar activity dependence of the quiet-time ionospheric trough
NASA Astrophysics Data System (ADS)
Ishida, T.; Ogawa, Y.; Kadokura, A.; Hiraki, Y.; Häggström, I.
2014-08-01
We have conducted a statistical analysis of the ionospheric F region trough, focusing on its seasonal variation and solar activity dependence under geomagnetically quiet and moderate conditions, using plasma parameter data obtained via Common Program 3 observations performed by the European Incoherent Scatter (EISCAT) radar between 1982 and 2011. We have confirmed that there is a major difference in frictional heating between the high- and low-latitude sides of the EISCAT field of view (FOV) at ~73°0'N-60°5'N (geomagnetic latitude) at an altitude of 325 km, which is associated with trough formation. Our statistical results show that the high-latitude and midlatitude troughs occur on the high- and low-latitude sides of the FOV, respectively. Seasonal variations indicate that dissociative recombination accompanied by frictional heating is a main cause of trough formation in sunlit regions. During summer, therefore, the occurrence rate is maintained at 80-90% in the postmidnight high-latitude region owing to frictional heating by eastward return flow. Solar activity dependence on trough formation indicates that field-aligned currents modulate the occurrence rate of the trough during the winter and equinox seasons. In addition, the trough becomes deeper via dissociative recombination caused by an increased ion temperature with F10.7, at least in the equinox and summer seasons but not in winter.
NASA Astrophysics Data System (ADS)
Guo, Minghuan; Wang, Zhifeng; Sun, Feihu
2016-05-01
The optical efficiencies of a solar trough concentrator are important to the whole thermal performance of the solar collector, and the outer surface of the tube absorber is a key interface of energy flux. So it is necessary to simulate and analyze the concentrated solar flux density distributions on the tube absorber of a parabolic trough solar collector for various sun beam incident angles, with main optical errors considered. Since the solar trough concentrators are linear focusing, it is much of interest to investigate the solar flux density distribution on the cross-section profile of the tube absorber, rather than the flux density distribution along the focal line direction. Although a few integral approaches based on the "solar cone" concept were developed to compute the concentrated flux density for some simple trough concentrator geometries, all those integral approaches needed special integration routines, meanwhile, the optical parameters and geometrical properties of collectors also couldn't be changed conveniently. Flexible Monte Carlo ray trace (MCRT) methods are widely used to simulate the more accurate concentrated flux density distribution for compound parabolic solar trough concentrators, while generally they are quite time consuming. In this paper, we first mainly introduce a new backward ray tracing (BRT) method combined with the lumped effective solar cone, to simulate the cross-section flux density on the region of interest of the tube absorber. For BRT, bundles of rays are launched at absorber-surface points of interest, directly go through the glass cover of the absorber, strike on the uniformly sampled mirror segment centers in the close-related surface region of the parabolic reflector, and then direct to the effective solar cone around the incident sun beam direction after the virtual backward reflection. All the optical errors are convoluted into the effective solar cone. The brightness distribution of the effective solar cone is supposed to be circular Gaussian type. Then a parabolic trough solar collector of Euro Trough 150 is used as an example object to apply this BRT method. Euro Trough 150 is composed of RP3 mirror facets, with the focal length of 1.71m, aperture width of 5.77m, outer tube diameter of 0.07m. Also to verify the simulated flux density distributions, we establish a modified MCRT method. For this modified MCRT method, the random rays with weighted energy elements are launched in the close-related rectangle region in the aperture plane of the parabolic concentrator and the optical errors are statistically modeled in the stages of forward ray tracing process. Given the same concentrator geometric parameters and optical error values, the simulated results from these two ray tracing methods are in good consistence. The two highlights of this paper are the new optical simulation method, BRT, and figuring out the close-related mirror surface region for BRT and the close-related aperture region for MCRT in advance to effectively simulate the solar flux distribution on the absorber surface of a parabolic trough collector.
NASA Astrophysics Data System (ADS)
Gauthier, N.; Claud, C.; Funatsu, B. M.; Chaboureau, J.-P.; Argence, S.; Lambert, D.; Richard, E.; Hauchecorne, A.; Arbogast, P.; Maynard, K.
2009-09-01
Heavy precipitation events over the Mediterranean Sea are generally associated with upper-level troughs. The mesoscale structures of such troughs are however not well reproduced by the atmospheric analyses due to inappropriate spatial resolution. We propose here to use a semi-Lagrangian advection model called MIMOSA (Modélisation Isentrope du transport Méso-échelle de l'Ozone Stratosphérique par Advection) initially developed to describe stratospheric filaments, to calculate fine-scale Potential Vorticity (PV) fields on isentropic surfaces near the tropopause. After a description of MIMOSA, we will focus on the model-generated PV fields for several high impact weather cases that occurred over the Western Mediterreanean Sea. We will demonstrate the ability of MIMOSA to resolve fine scale structures of upper-level troughs considering the Algiers' flash flood, which occurred on November 2001, and then a heavy precipitation event over southeast France on the 5-6 September 2005. Finally, with a PV inversion method, we will show the impact of the fine scales PV structures as depicted by MIMOSA to improve the numerical simulation of a « hurricane » that hit Italy in September 2006, both in terms of surface pressure and precipitation forecasts.
Concentrating Solar Power Projects - ASE Demo Plant | Concentrating Solar
: Parabolic trough Turbine Capacity: Gross: 0.35 MW Status: Operational Start Year: 2013 Do you have more Start Production: 2013 Project Type: Demonstration Participants Developer(s): Archimede Solar Energy
Structural features related to the volcanic gases in Southern Okinawa Trough
NASA Astrophysics Data System (ADS)
Wang, H. F.; Hsu, S. K.; Tsia, C. H.; Chen, S. C.; Wu, M. F.
2016-12-01
The Okinawa Trough is a rifted back-arc basin, heavily sedimented and formed in an intracontinental rift zone behind the Ryukyu trench-arc system. The Southern Okinawa Trough (SOT) east of Taiwan is the place where post-collisional extension happened. The collision moved southwestward and the Ryukyu trench-arc extension westward, Arc volcanism is dominant in the Northern Ryukyu volcanic arc and back-arc volcanism in the Southern Okinawa Trough. Marine geophysical data including side-scan sonar (SSS), sub-bottom profiler (SBP) and echo sounder system (EK60) data are used in this study. Active fluid activities out of seafloor are obvious from various images observed on these data, such as gas plumes. These hydrothermal vents have been located at a water depth of 1400 m. Our preliminary results show that gas seepage structures appear in the location where is a week zone, such as a normal fault in the slope. The hydrothermal activity within the Okinawa Trough is associated with volcanism located in rift zones in the Southern Okinawa Trough. However, the origin of the submarine hydrothermal fluids within the Okinawa Trough is diverse with contributions from volcanic, sedimentary and magmatic sources, needed further investigations.
Characterization and physical properties of hydrate bearing sediments
NASA Astrophysics Data System (ADS)
Terzariol, M.; Santamarina, C.
2016-12-01
The amount of carbon trapped in hydrates is estimated to be larger than in conventional oil and gas reservoirs, thus methane hydrate is a promising energy resource. The high water pressure and the relatively low temperature needed for hydrate stability restrict the distribution of methane hydrates to continental shelves and permafrost regions. Stability conditions add inherent complexity to coring, sampling, handling, testing and data interpretation, have profound implications on potential production strategies. Thus a novel technology is developed for handling, transferring, and testing of natural hydrate bearing sediments without depressurization in order to preserve the sediment structure. Results from the first deployment of these tools on natural samples from Nankai Trough, Japan will also be summarized. Finally, to avoid consequences of poor sampling, a new multi-sensor in-situ characterization tool will be introduced.
Geophysical basin structure of the Cotonou (Dahomey/Benin) basin, West African Gulf of Guinea
DOE Office of Scientific and Technical Information (OSTI.GOV)
Babalola, O.O.
1990-05-01
The frontier Cotonou basin (or Dahomey/Benin embayment), situated west of the prolific Niger Delta basin, appears from seismic, gravity, and aeromagnetic interpretation, as a series of grabens and troughs confined on the west and east by the Romanche and the Chain fracture zones, respectively. The Keta trough of the western basin rim was formed by a 2700-m southeasterly downthrow of the Adina fault. This trough is separated by a north-northeasterly fault from the Lome-Anecho gravity high. Eastward, the arcuate Allada-Adjohon trough is abutted on its southern flank by the northwest-trending Nokue-Afowo trough and separated from the northwesterly Ikorodu trough bymore » the 50-km-wide aeromagnetically inferred ro-Otta ridge. The Ikorodu trough is adjoined on the northwest by the Aiyetoro trough and on the southeast by the Yemoja offshore graben trending east northeast as the Seme oil-field structural trend. North of the regional northeasterly axial, gravity positive, structural divide (the continental precursor of the Charcot fracture zone) a series of half-grabens (notably the Aplahoue, Bohicon, and Keiou troughs), normal faulted eastward and downthrown in the west, dominate the landward western rim of the Cotonou basin. Graben-bounding faults control the upper valleys of the basin drainage, converge toward the regional intrabasin structural trend and continue into the Fenyi-koe fault and the Charcot fracture zone. These faults resulted from brittle dextral shear of continental crust oblique to local, preexisting north-northeast structural trends. In the eastern basin rim, preexisting north-northwest structural trends influenced the shearing stress regime to generate small, shallow, structurally bounded, east-northeast- and north-northwest trending grabens.« less
NASA Technical Reports Server (NTRS)
Carlson, J. M.; Chayes, J. T.; Swindle, G. H.; Grannan, E. R.
1990-01-01
The scaling behavior of sandpile models is investigated analytically. First, it is shown that sandpile models contain a set of domain walls, referred to as troughs, which bound regions that can experience avalanches. It is further shown that the dynamics of the troughs is governed by a simple set of rules involving birth, death, and coalescence events. A simple trough model is then introduced, and it is proved that the model has a phase transition with the density of the troughs as an order parameter and that, in the thermodynamic limit, the trough density goes to zero at the transition point. Finally, it is shown that the observed scaling behavior is a consequence of finite-size effects.
Drobne, David; Bossuyt, Peter; Breynaert, Christine; Cattaert, Tom; Vande Casteele, Niels; Compernolle, Griet; Jürgens, Matthias; Ferrante, Marc; Ballet, Vera; Wollants, Willem-Jan; Cleynen, Isabelle; Van Steen, Kristel; Gils, Ann; Rutgeerts, Paul; Vermeire, Severine; Van Assche, Gert
2015-03-01
The addition of immunomodulators increases the efficacy of maintenance therapy with infliximab for up to 1 year in patients with Crohn's disease who have not been previously treated with immunomodulators. However, there are questions about the effect of withdrawing immunomodulator therapy from these patients. We studied the effects of treatment with infliximab and immunomodulators (co-treatment) and then immunomodulator withdrawal on long-term outcomes of patients, as well as trough levels of infliximab and formation of anti-infliximab antibodies (ATI). In a retrospective study with the median follow-up period of 34 months (interquartile range, 19-58 months), we analyzed data from 223 patients treated for Crohn's disease between May 1999 and December 2010 at the University Hospitals, Leuven, Belgium (65 received infliximab monotherapy, 158 received infliximab and an immunomodulator). Trough levels of infliximab and levels of ATI were measured in blood samples collected from 117 patients throughout co-treatment, as well as the time of immunomodulator withdrawal and after withdrawal. Patients receiving co-treatment had higher trough levels of infliximab (adjusted mean increase, 1.44-fold) than those receiving infliximab monotherapy (95% confidence interval [CI], 1.07-1.92; P = .02). A smaller percentage of patients receiving co-treatment developed ATI (35 of 158, 22%) than those receiving infliximab monotherapy (25 of 65, 38%; P = .01). Among co-treated patients, levels of infliximab remained stable after immunomodulators were withdrawn (before: 3.2 μg/mL; 95% CI, 1.6-5.8 μg/mL and after: 3.7 μg/mL; 95% CI, 1.3-6.3 μg/mL; P = .70). After withdrawal of immunomodulators, 45 of 117 patients (38%) required increasing doses of infliximab, and 21 of 117 (18%) discontinued infliximab. At the time of immunomodulator withdrawal, trough levels of infliximab and C-reactive protein were most strongly associated with response to infliximab thereafter. In a retrospective analysis, we confirmed that withdrawal of immunomodulators after at least 6 months (median, 13 months) of co-treatment with infliximab does not reduce the trough levels of infliximab in patients with Crohn's disease. Detectable trough levels of infliximab at the time of immunomodulator withdrawal are associated with long-term response. Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Cao, Xi; Li, Tim; Peng, Melinda; Chen, Wen; Chen, Guanghua
2014-06-01
The western North Pacific monsoon trough (MT) exhibits marked interannual variation (IAV) associated with El Niño-Southern Oscillation forcing. The role of MT IAV in tropical cyclone (TC) development was investigated using the Advanced Research Weather Research and Forecasting model placed on a beta plane. It was found that MT IAV has a great influence on vortex development. In strong years, the MT provides more favorable environmental conditions—primarily through enhanced low-level vorticity, convergence and midlevel moisture—for TC formation and vice versa in weak years. Sensitivity experiments that separated the dynamic and thermodynamic (moisture) factors from strong MT IAV showed that the thermodynamic impact associated with MT IAV is comparable to the dynamic impact.
The impact of the structural features of the rock mass on seismicity in Polish coal mines
NASA Astrophysics Data System (ADS)
Patyńska, Renata
2017-11-01
The article presents seismic activity induced in the coal mines of the Upper Silesian Coal Basin (GZW) in relation to the locations of the occurrence of rockbursts. The comparison of these measurements with the structural features of the rock mass of coal mines indicates the possibility of estimating the so-called Unitary Energy Expenditure (UEE) in a specific time. The obtained values of UEE were compared with the distribution of seismic activity in GZW mines. The level of seismic activity in the analysed period changed and depended on the intensity of mining works and diverse mining and geological conditions. Five regions, where tremors occurred (Bytom Trough, Main Saddle, Main Trough, Kazimierz Trough, and Jejkowice and Chwałowice Trough) which belong to various structural units of the Upper Silesia were analyzed. It was found out that rock bursts were recorded only in three regions: Main Saddle, Bytom Trough, and Jejkowice and Chwałowice Trough.
Stress Fields Along Okinawa Trough and Ryukyu Arc Inferred From Regional Broadband Moment Tensors
NASA Astrophysics Data System (ADS)
Kubo, A.; Fukuyama, E.
2001-12-01
Most shallow earthquakes along Okinawa trough and Ryukyu arc are relatively small (M<5.5). Focal mechanism estimations for such events were difficult due to insufficient dataset. However, this situation is improved by regional broadband network (FREESIA). Lower limit of magnitude of the earthquakes determined becomes 1.5 smaller in M{}w than that of Harvard moment tensors. As a result, we could examine the stress field in more detail than Fournier et al.(2001, JGR, 106, 13751-) did based on surface geology and teleseismic moment tensors. In the NE Okinawa trough, extension axes are oblique to the trough strike, while in SW Okinawa trough, they are perpendicular to the trough. Fault type in SW is normal fault and gradually changes to mixture of normal and strike slip toward NE. In the Ryukyu arc, extension axes are parallel to the arc. Although this feature is not clear in the NW Ryukyu arc, arc parallel extension may be a major property of entire arc. Dominant fault type is normal fault and several strike slips with the same extensional component are included. The volcanic train is located at the edge of arc parallel extension field faced A simple explanation of the arc parallel extension is the response to the opening motion of the Okinawa trough. Another possible mechanism is forearc movement due to oblique subduction which is enhanced in SW. We consider that the Okinawa trough and the Ryukyu arc are independent stress provinces.
Complex Burial and Exhumation of South Polar Cap Pitted Terrain
NASA Technical Reports Server (NTRS)
2000-01-01
This image is illuminated by sunlight from the upper left. The two prominent bright stripes at the left/center of the image are covered with bright frost and thus create the illusion that they are sunlit from the lower left.
The large pits, troughs, and 'swiss cheese' of the south polar residual cap appear to have been formed in the upper 4 or 5 layers of the polar material. Each layer is approximately 2 meters (6.6 feet) thick. Some Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images of this terrain show examples in which older pitted and eroded layers have been previously buried and are now being exhumed. The example shown here includes two narrow, diagonal slopes that trend from upper left toward lower right at the left/center portion of the frame. Along the bottoms of these slopes are revealed a layer that underlies them in which there are many more pits and troughs than in the upper layer. It is likely in this case that the lower layer formed its pits and troughs before it was covered by the upper layer. This observation suggests that the troughs, pits, and 'swiss cheese' features of the south polar cap are very old and form over long time scales.The picture is located near 84.6oS, 45.1oW, and covers an area 3 km by 5 km (1.9 x 3.1 mi) at a resolution of about 3.8 meters (12 ft) per pixel. The image was taken during southern spring on August 29, 1999.Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.NASA Astrophysics Data System (ADS)
Ubieta, Eduardo; Hoyo, Itzal del; Valenzuela, Loreto; Lopez-Martín, Rafael; Peña, Víctor de la; López, Susana
2017-06-01
A simulation model of a parabolic-trough solar collector developed in Modelica® language is calibrated and validated. The calibration is performed in order to approximate the behavior of the solar collector model to a real one due to the uncertainty in some of the system parameters, i.e. measured data is used during the calibration process. Afterwards, the validation of this calibrated model is done. During the validation, the results obtained from the model are compared to the ones obtained during real operation in a collector from the Plataforma Solar de Almeria (PSA).
NREL's Education Program in Action in the Concentrating Solar Power Program Advanced Materials Task
NASA Astrophysics Data System (ADS)
Kennedy, Cheryl
2010-03-01
Concentrating solar power (CSP) technologies use large mirrors to concentrate sunlight and the thermal energy collected is converted to electricity. The CSP industry is growing rapidly and is expected to reach 25 GW globally by 2020. Cost target goals are for CSP technologies to produce electricity competitive with intermediate-load power generation (i.e., natural gas) by 2015 with 6 hours of thermal storage and competitive in carbon constrained base load power markets (i.e., coal) by 2020 with 12-17 hours of thermal storage. The solar field contributes more than 40% of the total cost of a parabolic trough plant and together the mirrors and receivers contribute more than 25% of the installed solar field cost. CSP systems cannot hit these targets without aggressive cost reductions and revolutionary performance improvements from technology advances. NREL's Advanced Materials task in the CSP Advanced R&D project performs research to develop low cost, high performance, durable solar reflector and high-temperature receiver materials to meet these needs. The Advanced Materials task leads the world in this research and the task's reliance on NREL's educational program will be discussed.
2013-06-21
ISS036-E-011034 (21 June 2013) --- The Salton Trough is featured in this image photographed by an Expedition 36 crew member on the International Space Station. The Imperial and Coachella Valleys of southern California – and the corresponding Mexicali Valley and Colorado River Delta in Mexico – are part of the Salton Trough, a large geologic structure known to geologists as a graben or rift valley that extends into the Gulf of California. The trough is a geologically complex zone formed by interaction of the San Andreas transform fault system that is, broadly speaking, moving southern California towards Alaska; and the northward motion of the Gulf of California segment of the East Pacific Rise that continues to widen the Gulf of California by sea-floor spreading. According to scientists, sediments deposited by the Colorado River have been filling the northern rift valley (the Salton Trough) for the past several million years, excluding the waters of the Gulf of California and providing a fertile environment – together with irrigation—for the development of extensive agriculture in the region (visible as green and yellow-brown fields at center). The Salton Sea, a favorite landmark of astronauts in low Earth orbit, was formed by an irrigation canal rupture in 1905, and today is sustained by agricultural runoff water. A wide array of varying landforms and land uses in the Salton Trough are visible from space. In addition to the agricultural fields and Salton Sea, easily visible metropolitan areas include Yuma, AZ (lower left); Mexicali, Baja California, Mexico (center); and the San Diego-Tijuana conurbation on the Pacific Coast (right). The approximately 72-kilometer-long Algodones Dunefield is visible at lower left.
Performance and Simulation of a Stand-alone Parabolic Trough Solar Thermal Power Plant
NASA Astrophysics Data System (ADS)
Mohammad, S. T.; Al-Kayiem, H. H.; Assadi, M. K.; Gilani, S. I. U. H.; Khlief, A. K.
2018-05-01
In this paper, a Simulink® Thermolib Model has been established for simulation performance evaluation of Stand-alone Parabolic Trough Solar Thermal Power Plant in Universiti Teknologi PETRONAS, Malaysia. This paper proposes a design of 1.2 kW parabolic trough power plant. The model is capable to predict temperatures at any system outlet in the plant, as well as the power output produced. The conditions that are taken into account as input to the model are: local solar radiation and ambient temperatures, which have been measured during the year. Other parameters that have been input to the model are the collector’s sizes, location in terms of latitude and altitude. Lastly, the results are presented in graphical manner to describe the analysed variations of various outputs of the solar fields obtained, and help to predict the performance of the plant. The developed model allows an initial evaluation of the viability and technical feasibility of any similar solar thermal power plant.
Trough Coating Solar Cells Without Spillover
NASA Technical Reports Server (NTRS)
Heaps, J. D.
1986-01-01
Problem with trough coating of silicon on ceramic - spillover of molten silicon - overcome by combination of redesigned heaters and tiltable trough. Modifications make it possible to coat virtually any length of ceramic with film of solar-cell-grade silicon. Previously, maximum length coated before spillover occurred was 2 inches (5.1 cm).
NASA Technical Reports Server (NTRS)
2006-01-01
2 July 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a portion of a trough cutting across a dust-covered plain in the Labeatis Fossae region of Mars. Boulders derived from the layered exposures near the top of the trough walls are resting on the floor, and in some locations, the sloping sidewalls of the dusty trough. Location near: 22.1oN, 94.5oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern SpringNASA Astrophysics Data System (ADS)
Takahashi, T.; Obana, K.; Yamamoto, Y.; Nakanishi, A.; Kaiho, Y.; Kodaira, S.; Kaneda, Y.
2012-12-01
The Nankai trough in southwestern Japan is a convergent margin where the Philippine sea plate is subducted beneath the Eurasian plate. There are major faults segments of huge earthquakes that are called Tokai, Tonankai and Nankai earthquakes. According to the earthquake occurrence history over the past hundreds years, we must expect various rupture patters such as simultaneous or nearly continuous ruptures of plural fault segments. Japan Agency for Marine-Earth Science and Technology (JAMSTEC) conducted seismic surveys at Nankai trough in order to clarify mutual relations between seismic structures and fault segments, as a part of "Research concerning Interaction Between the Tokai, Tonankai and Nankai Earthquakes" funded by Ministry of Education, Culture, Sports, Science and Technology, Japan. This study evaluated the spatial distribution of random velocity inhomogeneities from Hyuga-nada to Kii-channel by using velocity seismograms of small and moderate sized earthquakes. Random velocity inhomogeneities are estimated by the peak delay time analysis of S-wave envelopes (e.g., Takahashi et al. 2009). Peak delay time is defined as the time lag from the S-wave onset to its maximal amplitude arrival. This quantity mainly reflects the accumulated multiple forward scattering effect due to random inhomogeneities, and is quite insensitive to the inelastic attenuation. Peak delay times are measured from the rms envelopes of horizontal components at 4-8Hz, 8-16Hz and 16-32Hz. This study used the velocity seismograms that are recorded by 495 ocean bottom seismographs and 378 onshore seismic stations. Onshore stations are composed of the F-net and Hi-net stations that are maintained by National Research Institute for Earth Science and Disaster Prevention (NIED) of Japan. It is assumed that the random inhomogeneities are represented by the von Karman type PSDF. Preliminary result of inversion analysis shows that spectral gradient of PSDF (i.e., scale dependence of inhomogeneities) are the same overt the Nankai trough, but random inhomogeneities at smaller wavenumber shows anomalously large values at the southwestern part of Hyuga-nada and Kii-channel. Anomaly at Hyuga-nada is almost located at the subducted Kyushu Palau ridge. Similar random inhomogeneities were imaged near the remnant of ancient arc in the northern Izu-Bonin arc (Takahashi et al. 2011). We speculate these random inhomogeneities reflect the remnant of ancient volcanic activities. These results imply that random inhomogeneities at Kii-channel are possibly related to the subducted seamount, and that random inhomogeneities are useful to discuss the medium characteristics in subduction zone.
Thalakada, Rosanne; Legal, Michael; Lau, Tim T Y; Luey, Tiffany; Batterink, Josh; Ensom, Mary H H
2012-01-01
Background: Recent guidelines recommend a vancomycin trough (predose) level between 15 and 20 mg/L in the treatment of invasive gram-positive infections, but most initial dosing nomograms are designed to achieve lower targets (5–15 mg/L). Clinicians need guidance about appropriate initial dosing to achieve the higher target. Objective: To develop and validate a high-target vancomycin dosing nomogram to achieve trough levels of 15–20 mg/L. Methods: A retrospective study was conducted at 2 teaching hospitals, St Paul’s Hospital and Vancouver General Hospital in Vancouver, British Columbia. Patients who were treated with vancomycin between January 2008 and June 2010 and who had achieved a trough level of 14.5–20.5 mg/L were identified. Demographic and clinical data were collected. Multiple linear regression was used to develop a vancomycin dosing nomogram for each hospital site. An integrated nomogram was constructed by merging the data from the 2 hospitals. A unique set of patients at each institution was used for validating their respective nomograms and a pooled group of patients for validating the integrated nomogram. Predictive success was evaluated, and a nomogram was deemed significantly different from another nomogram if p < 0.05 via “χ2 testing. Results: Data from 78 patients at one hospital and 91 patients at the other were used in developing the respective institutional nomograms. For each hospital’s data set, both age and initial serum creatinine were significantly associated with the predicted dosing interval (p < 0.001). Validation in a total of 105 test patients showed that the integrated nomogram had a predictive success rate of 56%. Conclusions: A novel vancomycin dosing nomogram was developed and validated at 2 Canadian teaching hospitals. This integrated nomogram is a tool that clinicians can use in selecting appropriate initial vancomycin regimens on the basis of age and serum creatinine, to achieve high-target levels of 15–20 mg/L. The nomogram should not replace clinical judgment for patients with unstable and/or reduced renal function. PMID:22783028
Concentrating Solar Power Projects - ISCC Duba 1 | Concentrating Solar
: Parabolic trough Turbine Capacity: Net: 43.0 MW Gross: 43.0 MW Status: Under construction Start Year: 2017 Solar Break Ground: 2016 Start Production: 2017 Participants Developer(s): Saudi Electricity Co. Owner(s
Kumar, Vinod; Afrin, Samia; Ortega, Jesus; ...
2013-09-01
A prototype of a concentrating solar collector (CSC) receiver was designed, built, and evaluated on-sun at the University of Texas at El Paso in El Paso, TX. This prototype receiver consists of two parabolic trough-reflectors but, in principle, the design can be efficiently extended to multiple units for achieving a higher temperature throughput. Each reflector has a vacuum tube collector at the focal point of the trough. The solar collector system was combined with a single-tank thermocline thermal energy storage (TES) for off-solar thermal usage. The main goal of this study is to develop an advanced solar hot water systemmore » for most residential applications. The focus of this study is to investigate the feasibility and performance of the solar thermal system by employing the recent advancement in the TES—a thermocline based TES—system for the concentrating solar power technologies developed by the Sandia National Laboratories and National Renewable Energy Laboratories for electricity production. A CSC when combined with TES has potential to provide uninterrupted thermal energy for most residential usages. This paper presents a detailed description of prototype design and materials required. The thermal energy storage tank utilizes an insulated 170 l (45 gal) galvanized steel tank. In order to maintain thermocline in the TES tank, with hot water on top and cold water at the bottom, two plate distributors are installed in the tank. The data showed a significant enhancement in thermal energy generation. This thermocline based single tank presented a thermal energy storage potential for at least three days (with diminishing storage capacity) that test were performed. The whole prototype was made for approximately USD 355 (excludes any labor costs) and hence also has strong potential for supplying clean thermal energy in most developing countries. As a result, tests of the prototype were conducted in November 2011.« less
Collison, Jake
2016-04-07
Cannon Air Force Base (Cannon AFB) is located in the High Plains physiographic region of east-central New Mexico, about 5 miles west of Clovis, New Mexico. The area surrounding Cannon AFB is primarily used for agriculture, including irrigated cropland and dairies. The Southern High Plains aquifer is the principal source of water for Cannon AFB, for the nearby town of Clovis, and for local agriculture and dairies. The Southern High Plains aquifer in the vicinity of Cannon AFB consists of three subsurface geological formations: the Chinle Formation of Triassic age, the Ogallala Formation of Tertiary age, and the Blackwater Draw Formation of Quaternary age. The Ogallala Formation is the main water-yielding formation of the Southern High Plains aquifer. Groundwater-supplied, center-pivot irrigation dominates pumping from the Southern High Plains aquifer in the area surrounding Cannon AFB, where the irrigation season typically extends from early March through October. The U.S. Geological Survey has been monitoring groundwater levels in the vicinity of Cannon AFB since 1954 and has developed general potentiometric-surface maps that show groundwater flow from northwest to southeast in the study area. While previous potentiometric-surface maps show the general direction of groundwater flow, a denser well network is needed to show details of groundwater flow at a local scale. Groundwater levels were measured in 93 wells during summer 2013 and 100 wells during winter 2015.The summer and winter potentiometric-surface maps display the presence of what is interpreted to be a groundwater trough trending from the northwest to the southeast through the study area. This groundwater trough may be the hydraulic expression of a Tertiary-age paleochannel. Groundwater north of the trough flows in a southerly direction into the trough, and groundwater south of the trough flows in an easterly direction into the trough.During the 18-month period between summer 2013 and winter 2015, changes in groundwater levels ranged from a rise of 10.0 to a decline of 3.8 feet. The regions to the north and south of the groundwater trough contained the majority of the rises in groundwater levels, whereas the regions within the trough contained the majority of the declines in groundwater levels. In contrast, the long-term groundwater-level trend in wells with 20 to 60 years of record is a steady decline in average annual water levels, with declines ranging from 0.41 to 2.81 feet per year. Overall, the northwestern part of the study area exhibits the smallest average annual declines, while the southeastern part of the study area exhibits the largest average annual declines.
Morphotectonics of the central Muertos thrust belt and Muertos Trough (northeastern Caribbean)
Granja, Bruna J.L.; ten Brink, Uri S.; Carbó-Gorosabel, Andrés; Muñoz-Martín, A.; Gomez, Ballesteros M.
2009-01-01
Multibeam bathymetry data acquired during the 2005 Spanish R/V Hesp??rides cruise and reprocessed multichannel seismic profiles provide the basis for the analysis of the morphology and deformation in the central Muertos Trough and Muertos thrust belt. The Muertos Trough is an elongated basin developed where the Venezuelan Basin crust is thrusted under the Muertos fold-and-thrust belt. Structural variations along the Muertos Trough are suggested to be a consequence of the overburden of the asymmetrical thrust belt and by the variable nature of the Venezuelan Basin crust along the margin. The insular slope can be divided into three east-west trending slope provinces with high lateral variability which correspond to different accretion stages: 1) The lower slope is composed of an active sequence of imbricate thrust slices and closed fold axes, which form short and narrow accretionary ridges and elongated slope basins; 2) The middle slope shows a less active imbricate structure resulting in lower superficial deformation and bigger slope basins; 3) The upper slope comprises the talus region and extended terraces burying an island arc basement and an inactive imbricate structure. The talus region is characterized by a dense drainage network that transports turbidite flows from the islands and their surrounding carbonate platform areas to the slope basins and sometimes to the trough. In the survey area the accommodation of the ongoing east-west differential motion between the Hispaniola and the Puerto Rico-Virgin Islands blocks takes place by means of diffuse deformation. The asymmetrical development of the thrust belt is not related to the geological conditions in the foreland, but rather may be caused by variations in the geometry and movement of the backstop. The map-view curves of the thrust belt and the symmetry of the recesses suggest a main north-south convergence along the Muertos margin. The western end of the Investigator Fault Zone comprises a broad band of active normal faults which result in high instability of the upper insular slope. ?? 2009 Elsevier B.V.
New Insight Into the Crustal Structure of the Continental Margin offshore NW Sabah/Borneo
NASA Astrophysics Data System (ADS)
Barckhausen, U.; Franke, D.; Behain, D.; Meyer, H.
2002-12-01
The continental margin offshore NW Sabah/Borneo (Malaysia) has been investigated with reflection and refraction seismics, magnetics, and gravity during the recent cruise BGR01-POPSCOMS. A total of 4000 km of geophysical profiles has been acquired, thereof 2900 km with reflection seismics. The focus of investigations was on the deep water areas. The margin looks like a typical accretionary margin and was presumably formed during the subduction of a proto South China Sea. Presently, no horizontal movements between the two plates are being observed. Like in major parts of the South China Sea, the area seaward of the Sabah Trough consists of extended continental lithosphere which is characterised by a pattern of rotated fault blocks and half grabens and a carbonate platform of Early Oligocene to Early Miocene age. We found evidence that the continental crust also underlies the Sabah Trough and the adjacent continental slope, a fact that raises many questions about the tectonic history and development of this margin. The tectonic pattern of the Dangerous Grounds' extended continental crust can be traced a long way landward of the Sabah Trough beneath the sedimentary succession of the upper plate. The magnetic anomalies which are dominated by the magnetic signatures of relatively young volcanic features also continue under the continental slope. The sedimentary rocks of the upper plate, in contrast, seem to generate hardly any magnetic anomalies. Based on the new data we propose the following scenario for the development of the NW Sabah continental margin: Seafloor spreading in the present South China Sea started at about 30 Ma in the Late Oligocene. The spreading process separated the Dangerous Grounds area from the SE Asian continent and ceased in late Early Miocene when the oceanic crust of the proto South China Sea was fully subducted in eastward direction along the Borneo-Palawan Trough. During Lower and/or Middle Miocene, Borneo rotated counterclockwise and was thrusted onto the edge of the rifted continental block of the Dangerous Grounds. The subducted oceanic crust of the proto South China Sea must today be located below the Eastern part of Sabah and not along the present NW Sabah Trough.
NASA Astrophysics Data System (ADS)
Parker, James; Pryse, Eleri; Jackson-Booth, Natasha
2017-04-01
The main ionospheric trough is a large-scale spatial depletion in the ionospheric electron density that commonly separates the auroral and mid-latitude regions. The feature covers several degrees in latitude and is extended in longitude. It exhibits substantial day-to-day variability in both the location of its minimum ionisation density and in its latitudinal structure. Observations from the UK have shown the trough to be a night-time feature, appearing in early evening to the north of the mainland and progressing equatorward during the course of the night. At dawn, photoionisation fills in the feature. Under increasing levels of geomagnetic activity, the trough moves progressively to lower latitudes. Steep gradients on the trough walls and their variability can cause problems for radio applications. EDAM can be used to model the ionosphere at the trough latitudes by assimilating ionospheric observations from this region into the International Reference Ionosphere (IRI). In this study troughs modelled by EDAM, assimilating data for a period from September to December 2002, are presented and are verified by comparisons with independent observations. Measurements of slant total electron content (sTEC) between GPS satellites and forty ground receivers in Europe were assimilated into EDAM to model the ionospheric electron density. The Vertical Total Electron Content (VTEC) was then calculated through the model, with the values at the longitude of 0.0E considered to obtain statistical characteristics of identified troughs parameters. Comparisons of the parameters with those obtained previously, using transmissions from the satellites of NIMS (Navy Ionospheric Monitoring System) orbiting at altitudes lower than GPS, revealed consistent results. Further support for the EDAM trough was obtained by comparisons of the model with independent GPS measurements. For this a GPS ground station not used in the assimilation was used to observe the sTEC to this "truth" station. Comparisons of these independent truth data with sTEC calculated through the model were used to determine the accuracy of EDAM in the vicinity of the trough.
Interpreting Observations of Large-Scale Traveling Ionospheric Disturbances by Ionospheric Sounders
NASA Astrophysics Data System (ADS)
Pederick, L. H.; Cervera, M. A.; Harris, T. J.
2017-12-01
From July to October 2015, the Australian Defence Science and Technology Group conducted an experiment during which a vertical incidence sounder (VIS) was set up at Alice Springs Airport. During September 2015 this VIS observed the passage of many large-scale traveling ionospheric disturbances (TIDs). By plotting the measured virtual heights across multiple frequencies as a function of time, the passage of the TID can be clearly displayed. Using this plotting method, we show that all the TIDs observed during the campaign by the VIS at Alice Springs show an apparent downward phase progression of the crests and troughs. The passage of the TID can be more clearly interpreted by plotting the true height of iso-ionic contours across multiple plasma frequencies; the true heights can be obtained by inverting each ionogram to obtain an electron density profile. These plots can be used to measure the vertical phase speed of a TID and also reveal a time lag between events seen in true height compared to virtual height. To the best of our knowledge, this style of analysis has not previously been applied to other swept-frequency sounder observations. We develop a simple model to investigate the effect of the passage of a large-scale TID on a VIS. The model confirms that for a TID with a downward vertical phase progression, the crests and troughs will appear earlier in virtual height than in true height and will have a smaller apparent speed in true height than in virtual height.
Fenton, L.K.; Herkenhoff, K. E.
2000-01-01
We present two photoclinometric profiles across a trough in the martian northern polar layered terrain. Complications caused by albedo variations were avoided by using an early springtime Viking image with a thin cover of seasonal CO2 frost. The topographic profiles were constrained with stereogrammetric elevations derived from summertime Viking images of the same region. We find that the photoclinometric profiles are consistent with a nearby MOLA (Mars Orbiter Laser Altimeter) track crossing the same polar trough. The trough is asymmetric, with higher relief and a steeper slope on the equatorward-facing wall. Individual layers are subdued and difficult to observe in the profiles. A decrease in both relief and elevation toward the eastern end of the trough suggests that layers become thinner to the east. Declining equatorward slopes in the eastern portion of the trough imply that erosion rates have varied along the trough. The variation in erosion rate may be linked to the change in layer thickness along the trough. Layers have an average thickness of 19??8 m in the center of the trough and 59??32 m on the northern wall. The northern wall is most likely composed of thinner layers that are obscured. To first order, we find that a 19-m layer requires 16,000 years of deposition to form. Although this timescale does not coincide with orbital variation periods of 105 and 106 years, deposition rates may not be constant and thus the 16,000-year layer formation time does not preclude layer formation during part of each orbital oscillation. ?? 2000 Academic Press.
Meta-analysis of medical intervention for normal tension glaucoma.
Cheng, Jin-Wei; Cai, Ji-Ping; Wei, Rui-Li
2009-07-01
To evaluate the intraocular pressure (IOP) reduction achieved by the most frequently prescribed antiglaucoma drugs in patients with normal tension glaucoma (NTG). Systematic review and meta-analysis. Fifteen randomized clinical trials reported 25 arms for peak IOP reduction, 16 arms for trough IOP reduction, and 13 arms for diurnal curve IOP reduction. Pertinent publications were identified through systematic searches of PubMed, EMBASE, and the Cochrane Controlled Trials Register. The patients had to be diagnosed as having NTG. Methodological quality was assessed by the Delphi list on a scale from 0 to 18. The pooled 1-month IOP-lowering effects were calculated using the 2-step DerSimonian and Laird estimate method of the random effects model. Absolute and relative reductions in IOP from baseline for peak and trough moments. Quality scores of included studies were generally high, with a mean quality score of 12.7 (range, 9-16). Relative IOP reductions were peak, 15% (12%-18%), and trough, 18% (8%-27%) for timolol; peak, 14% (8%-19%), and trough, 12% (-7% to 31%) for dorzolamide; peak, 24% (17%-31%), and trough, 11% (7%-14%) for brimonidine; peak, 20% (17%-24%), and trough, 20% (18%-23%) for latanoprost; peak, 21% (16%-25%), and trough, 18% (14%-22%) for bimatoprost. The differences in absolute IOP reductions between prostaglandin analogues and timolol varied from 0.9 to 1.0 mmHg at peak and -0.1 to 0.2 mmHg at trough. Latanoprost, bimatoprost, and timolol are the most effective IOP-lowering agents in patients with NTG.
Ramp sedimentation in the Dinantian limestones of the Shannon Trough, Co. Limerick, Ireland
NASA Astrophysics Data System (ADS)
Somerville, Ian D.; Strogen, Peter
1992-08-01
During the late Chadian and Arundian (Lower Carboniferous), an extensive carbonate ramp (Limerick Ramp) developed over County Limerick, southwest Ireland, dipping northwestwards. Three distinct facies can be recognised corresponding to position on this ramp: inner, mid- and outer ramp. The inner ramp facies of oolitic and crinoidal grainstones (Herbertstown Limestone Formation) in east Limerick formed a major shoal behind which peritidal limestones were deposited. The mid-ramp facies of muddy bioclastic limestones and shales (Cooperhill facies) in north Limerick formed between fairweather and storm wave bases. The outer ramp (basinal) facies of mudstones and thin graded resedimented limestones (Rathkeale Beds) in west Limerick developed below storm wave base when fine terrigenous input was high. Later in the Arundian there was progradation of the nearshore oolitic and crinoidal grainstones over the mid-ramp facies. By the Holkerian, the deep-water basinal facies in west Limerick was buried beneath mid-ramp facies (Durnish Limestone). The initiation of the Limerick Ramp is closely related to the formation of the Shannon Trough. In the late Courceyan, accelerated subsidence in the Shannon area during deposition of Waulsortian facies marked the onset of a sag phase. Following a quiescent period in early Chadian, subsidence was renewed in the late Chadian and Arundian, when major facies changes occurred on the ramp. Comparison of the Shannon Trough with the Dublin Basin shows that in the latter, tectonic events in the Chadian and Arundian, particularly syn-sedimentary faulting, created a sharp division between platform and basinal sedimentation. Such tectonic influence is not recognised in the Shannon Trough. Here differential subsidence and eustatic sea-level changes led to more permanent ramp existence, modified only by westwards progradation.
NASA Astrophysics Data System (ADS)
Shettima, B.; Abubakar, M. B.; Kuku, A.; Haruna, A. I.
2018-01-01
Facies analysis of the Cretaceous Bima Formation in the Gongola Sub -basin of the Northern Benue Trough northeastern Nigeria indicated that the Lower Bima Member is composed of alluvial fan and braided river facies associations. The alluvial fan depositional environment dominantly consists of debris flow facies that commonly occur as matrix supported conglomerate. This facies is locally associated with grain supported conglomerate and mudstone facies, representing sieve channel and mud flow deposits respectively, and these deposits may account for the proximal alluvial fan region of the Lower Bima Member. The distal fan facies were represented by gravel-bed braided river system of probably Scot - type model. This grade into sandy braided river systems with well developed floodplains facies, forming probably at the lowermost portion of the alluvial fan depositional gradient, where it inter-fingers with basinal facies. In the Middle Bima Member, the facies architecture is dominantly suggestive of deep perennial sand-bed braided river system with thickly developed amalgamated trough crossbedded sandstone facies fining to mudstone. Couplets of shallow channels are also locally common, attesting to the varying topography of the basin. The Upper Bima Member is characterized by shallow perennial sand-bed braided river system composed of successive succession of planar and trough crossbedded sandstone facies associations, and shallower channels of the flashy ephemeral sheetflood sand - bed river systems defined by interbedded succession of small scale trough crossbedded sandstone facies and parallel laminated sandstone facies. The overall stacking pattern of the facies succession of the Bima Formation in the Gongola Sub - basin is generally thinning and fining upwards cycles, indicating scarp retreat and deposition in a relatively passive margin setting. Dominance of kaolinite in the clay mineral fraction of the Bima Formation points to predominance of humid sub - tropical to tropical climatic conditions. This favors pedogenic activities which are manifested in the several occurrences of paleosols. Pronounced periods of arid climatic conditions are also notable from the subordinate smectite mineralization. Chlorite mineralization at some localities is indicative of elevation of the provenance area, and this is synonymous with deposition of the Bima Formation, because of its syn - depositional tectonics. The absences of lacustrine shales in the syn - rift stratigraphic architecture of the Bima Formation indicates that the lower Cretaceous petroleum system that are common in the West and Central African Rift basins are generally barren in the Gongola Sub - basin of the Northern Benue Trough.
Code of Federal Regulations, 2010 CFR
2010-01-01
..., troughs, and other equipment used for infected poultry. 82.21 Section 82.21 Animals and Animal Products... ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS EXOTIC NEWCASTLE DIS- EASE (END) AND CHLAMYDIOSIS Chlamydiosis in Poultry § 82.21 Vehicles, cages, coops, containers, troughs, and other equipment used for...
Evolution of the Outflows in NGC 3516
NASA Astrophysics Data System (ADS)
Dunn, Jay P.; Parvaresh, Rozhin; Kraemer, S. B.; Crenshaw, D. Michael
2018-02-01
We analyze the 2011 HST/COS spectrum of the Seyfert 1 galaxy NGC 3516, which demonstrates clear changes in one of the intrinsic absorption troughs (component 5), slight evidence of change in a second trough (component 6), and the appearance of a new absorption trough (component 9). We interpret both the changes and the appearance of the new trough as bulk motion across the line of sight. The implied lower limit on the transverse velocity of component 5 is 360 km s‑1, compared to the earlier 2001 HST/STIS spectrum, while the lower limits for components 6 and 9 are 920 km s‑1, based on 2009 FUSE data. Component 5 also exhibits a shift in velocity centroid. This is only the second known case of this behavior in a Seyfert galaxy. Due to the high quality of the HST/COS spectrum, we identify a previously undetected trough due to an excited state of Si II for component 1. In combination with the resonance trough of Si II and photoionization modeling, we directly determine the distance of the component 1 outflow to be 67.2 pc.
Xie, Qiyuan; Tu, Ran; Wang, Nan; Ma, Xin; Jiang, Xi
2014-02-28
The objective of this work is to quantitatively investigate the dripping-burning and flowing fire of thermoplastics. A new experimental setup is developed with a heating vessel and a T-trough. Hot thermoplastic liquids are generated in the vessel by electric heating. N2 gas is continuously injected into the vessel to avoid a sudden ignition of fuel in it. The detailed flowing burning behaviors of pool fire in the T-trough are analyzed through the measurements of the mass, heat flux and temperatures etc. The experimental results suggest that a continuous dripping of melted thermoplastic liquids in a nearly constant mass rate can be successfully made in the new setup. It also shows that the mass dripping rate of melted PS liquid is smaller than PP and PE since its large viscosity. In addition, the flame spread velocities of hot liquids of PS in the T-trough are also smaller than that of PP and PE because of its large viscosity. The mass burning rate of the PP and PE pool fire in T-trough are smaller than PS. Finally, considering the heating, melting, dripping and flowing burning behaviors of these polymers, it is suggested that the fire hazard of PE and PP are obviously higher than PS for their faster flowing burning. Copyright © 2013 Elsevier B.V. All rights reserved.
Concentrating Solar Power Projects - Morón | Concentrating Solar Power |
, 2018 Project Overview Project Name: Morón Country: Spain Location: Morón de la Frontera (Seville ? Background Technology: Parabolic trough Status: Operational Country: Spain City: Morón de la Frontera Region NREL Morón This page provides information on Morón, a concentrating solar power (CSP) project
Ueshima, Satoshi; Hira, Daiki; Fujii, Ryo; Kimura, Yuuma; Tomitsuka, Chiho; Yamane, Takuya; Tabuchi, Yohei; Ozawa, Tomoya; Itoh, Hideki; Horie, Minoru; Terada, Tomohiro; Katsura, Toshiya
2017-09-01
During anticoagulant therapy, major bleeding is one of the most severe adverse effects. This study aimed to evaluate the relationships between ABCB1, ABCG2, and CYP3A5 polymorphisms and plasma trough concentrations of apixaban, a direct inhibitor of coagulation factor X. A total of 70 plasma concentrations of apixaban from 44 Japanese patients with atrial fibrillation were analyzed. In these analyses, the plasma trough concentration/dose (C/D) ratio of apixaban was used as a pharmacokinetic index and all data were stratified according to the presence of ABCB1 (ABCB1 1236C>T, 2677G>T/A, and 3435C>T), ABCG2 (ABCG2 421C>A), and CYP3A5 (CYP3A5*3) polymorphisms. Influences of various clinical laboratory parameters (age, serum creatinine, estimated glomerular filtration rate, aspartate amino transferase, and alanine amino transferase) on the plasma trough C/D ratio of apixaban were included in analyses. Although no ABCB1 polymorphisms affected the plasma trough C/D ratio of apixaban, the plasma trough C/D ratio of apixaban was significantly higher in patients with the ABCG2 421A/A genotype than in patients with the ABCG2 421C/C genotype (P<0.01). The plasma trough C/D ratio of apixaban in patients with CYP3A5*1/*3 or *3/*3 genotypes was also significantly higher than that in patients with the CYP3A5*1/*1 genotype (P<0.05). Furthermore, the plasma trough C/D ratio of apixaban decreased with increased estimated glomerular filtration rate. These results indicate that ABCG2 421A/A and CYP3A5*3 genotypes and renal function are considered potential factors affecting trough concentrations of apixaban.
Specifications for structural range improvements.
H. Reed Sanderson; Thomas M. Quigley; Emery E. Swan; Louis R. Spink
1990-01-01
Construction specifications and illustrations are provided for several types of barbed wire and pole fences, gates, cattle guards, stiles, spring developments, water troughs, stock ponds, trick tanks, and livestock access trails.
Gangodagamage, Chandana; Wullschleger, Stan
2014-07-03
This dataset represent a map of the high center (HC) and low center (LC) polygon boundaries delineated from high resolution LiDAR data for the arctic coastal plain at Barrow, Alaska. The polygon troughs are considered as the surface expression of the ice-wedges. The troughs are in lower elevations than the interior polygon. The trough widths were initially identified from LiDAR data, and the boundary between two polygons assumed to be located along the lowest elevations on trough widths between them.
NASA Astrophysics Data System (ADS)
Sorlien, C. C.; Luyendyk, B. P.; Wilson, D. S.; Decesari, R. C.; Bartek, L. R.; Diebold, J. B.
2006-12-01
The extent of the West Antarctic ice sheet during mid-Cenozoic time is controversial and important to climate models. High-resolution multichannel seismic reflection data were acquired using the RVIB Palmer along the edge of the Ross Ice Shelf across the Eastern Basin of Ross Sea, in an area where calving of the ice shelf has exposed seafloor that has not been accessible to marine geophysics in several decades. A sub-basin in the far southeast corner of Ross Sea contains a succession of sediment-filled troughs, each capped by an unconformity. These troughs range between 2 and 20 km across, are 100 to 150 m-deep, with the narrower ones bounded by flat-topped ridges interpreted as moraines. We interpret the troughs interval to slightly predate 25 Ma. Reflections just 100 m below the troughs interval can be directly correlated to near DSDP270 where they underlie strata dated at ~25 Ma. A deeper stack of prograding sequences associated with a flat- topped ridge are interpreted as pre-25 Ma, possibly early Oligocene, deltas formed adjacent to the grounding line of a glacier, and the flat-topped ridge to be a moraine. The shallowest of the stack of unconformities capping the broad troughs can be projected across a basement ridge on trend with Roosevelt Island to a regional angular unconformity ("Red"), present across 70 km to deep sedimentary Eastern Basin. This unconformity represents about 1 km of missing stratigraphic section, is smooth and level, and splits into several major sequence boundaries within deep Eastern Basin. The second shallowest of these boundaries is dated about 14 Ma at DSDP-270. We interpret this unconformity to be cut by regional thick, grounded ice at depths several hundred meters below sea level. Pre-25 Ma strata show evidence of narrow erosional troughs and reflective mounds or ridges on the west flank of the basement ridge, but such features are not present in southern deep Eastern Basin near the ice shelf edge. This is evidence that the troughs were carved by glaciers issuing from distant highlands of Marie Byrd Land and not from East Antarctica. Late Oligocene through mid Miocene and younger prograding and unconformities farther north in Eastern Basin indicate grounded ice there. One possible interpretation is that "Red" was cut by thick, grounded ice that affected all of the Eastern Ross Sea paleo-shelf, while the pre-25 Ma glaciers affected only the area proximal to Marie Byrd Land. Late Oligocene glaciation on the outer shelf above deep Eastern Basin may have been sourced from East Antarctica and/or Central High. Evidence for pre-25 Ma glaciation proximal to Marie Byrd Land, combined with evidence for Oligocene ice caps at widely-separated localities of West Antarctica, allow the interpretation that portions of the West Antarctic Ice Sheet developed during Oligocene time. The broad troughs and the stack of prograding sequences may be related to dynamic ice caps and sea level falls in mid Oligocene and earliest Oligocene time. The Middle Miocene Red unconformity may be related to development of polar (cold-base) ice sheets. Oligocene glaciation implies that Marie Byrd Land and eastern Ross Sea have subsided from higher elevation due to cooling after late Cretaceous crustal thinning.
Sedimentation and tectonics of the Sylhet trough, Bangladesh
Johnson, S.Y.; Nur Alam, A.M.
1991-01-01
The Sylhet trough, a sub-basin of the Bengal Basin in northeastern Bangladesh, contains a thick fill (12 to 16 km) of late Mesozoic and Cenozoic strata that record its tectonic evolution. Stratigraphic, sedimentologic, and petrographic data collected from outcrops, cores, well logs, and seismic lines are used to reconstruct the history of this trough. -from Authors
Concentrating Solar Power Projects - Yumen 50MW Thermal Oil Trough CSP
project | Concentrating Solar Power | NREL Thermal Oil Trough CSP project Status Date : September 28, 2016 Project Overview Project Name: Yumen 50MW Thermal Oil Trough CSP project Country: China : Thermal Oil Power Block Turbine Capacity (Gross): 50.0 MW Turbine Capacity (Net): 50.0 MW Output Type
Nair, Ranjith G; Bharadwaj, P J; Samdarshi, S K
2016-12-01
This work reports the details of the design components and materials used in a linear compound parabolic trough reactor constructed with an aim to use the photocatalyst for solar photocatalytic applications. A compound parabolic trough reactor has been designed and engineered to exploit both UV and visible part of the solar irradiation. The developed compound parabolic trough reactor could receive almost 88% of UV radiation along with a major part of visible radiation. The performance of the reactor has been evaluated in terms of degradation of a probe pollutant using the parameters such as rate constant, residence time and photonic efficiency. An attempt has been made to assess the performance in different ranges of solar spectrum. Finally the developed reactor has been employed for the photocatalytic treatment of a paper mill effluent using Degussa P25 as the photocatalyst. The paper mill effluent collected from Nagaon paper mill, Assam, India has been treated under both batch mode and continuous mode using Degussa P25 photocatalyst under artificial and natural solar radiation, respectively. The photocatalytic degradation kinetics of the paper mill effluent has been determined using the reduction in total organic carbon (TOC) values of the effluent. Copyright © 2015 Elsevier Inc. All rights reserved.
Geophysical investigations of the tectonic boundary between East and West Antarctica
ten Brink, Uri S.; Bannister, S.; Beaudoin, B.C.; Stern, T.A.
1993-01-01
The Transantarctic Mountains (TAM), which separate the West Antarctic rift system from the stable shield of East Antarctica, are the largest mountains developed adjacent to a rift. The cause of uplift of mountains bordering rifts is poorly understood. One notion based on observations of troughs next to many uplifted blocks is that isostatic rebound produces a coeval uplift and subsidence. The results of an over-snow seismic experiment in Antarctica do not show evidence for a trough next to the TAM but indicate the extension of rifted mantle lithosphere under the TAM. Furthermore, stretching preceded the initiation of uplift, which suggests thermal buoyancy as the cause for uplift.
Morphological evolution of Jinshan Trough in Hangzhou Bay (China) from 1960 to 2011
NASA Astrophysics Data System (ADS)
Liu, Yifei; Xia, Xiaoming; Chen, Shenliang; Jia, Jianjun; Cai, Tinglu
2017-11-01
An extensive system of tidal channels, starting with Jinshan Trough in the east, is located along the north shore of Hangzhou Bay, China. This contribution investigates the morphological evolution of Jinshan Trough by using 17 bathymetric charts from a series covering a period of 51 years from 1960 to 2011. Three stages of evolution during this period are distinguishable based on the morphology and annual mean volume data. The first stage (1960-1987) is characterized by extension of the trough; the second stage (1987-1996) is a relatively stable period with some adjustments in the trough morphology; the third stage (1996-2011) is marked by the processes of erosion and deposition in the beginning of the period and a subsequent slow erosion process. Spatio-temporal variability of the trough was evaluated by using empirical orthogonal function (EOF) analysis. The first eigenfunction indicates that erosion is the main evolution process and there exists three stages similar to those distinguished from volume variations. The second eigenfunction mainly reflects erosion and deposition in the northwest part of the trough located in the flood tidal current shadow area of the artificial headland in Jinshan. The third eigenfunction mainly reflects annual fluctuations of erosion and deposition in the side slope at the artificial headland in Jinshan. A particularly intense erosion process occurred between 1996 and 1998. The major effects on morphological evolution in Jinshan Trough from 1960 to 2011 were investigated and tentative conclusions were presented. Continuous coastal reclamations in Jinshan had the most pronounced effect on the morphological evolution during the first and the second stages. The storm surge had a pronounced effect on the evolution at the beginning of the third stage.
NASA Astrophysics Data System (ADS)
Lucchitta, Baerbel K.
2010-10-01
The paper reviews the evolution of hypotheses of lakes in Valles Marineris through observations made from the time of Mariner and continuing through the Viking, MGS, MO, MEx, and MRO missions. Several pertinent findings from these missions are addressed, including: The morphology and composition of the interior layered deposits (ILD); the question whether ILD are deposited inside the troughs or exhumed from the walls; the possible existence of ancestral basins; the derivation of water; arguments for an origin as aqueous, eolian, or pyroclastic sediments, or sub/ice volcanoes; origin of inclined layers, mounds and moats; and age relations of features within and peripheral to the troughs. A possible scenario begins with the collapse of ice-charged ground into ancestral basins along structural planes of weakness due to Tharsis stresses, about 3.5 Ga ago. The basins rapidly filled with water from ground ice, subterranean aquifers, or nearby valley networks. The water spilled out of the peripheral troughs and flowed across high plateaus into early outflow channels. The ancestral basins then filled with sediments derived from valley networks or from trapped eolian or pyroclastic deposits. Alternatively, volcanoes rose under the water or ice to form tuyas. The water was highly acidic, and sediments may have been deposited directly as evaporites or were later altered to evaporites by the brines or by hydrothermal activity. Percolating fluids produced iron oxide concretions. Similar alteration would have affected the putative volcanoes. Most of the ILD were emplaced early in the troughs' history. Shortly thereafter, more water erupted from the peripheral troughs and formed additional chaos and outflow channels. The ancestral basins were breached by erosion and tectonism, and the through-going Coprates/Ius graben system developed. Major lakes within the Valles Marineris dried up and vigorous wind erosion reduced the friable, evaporite-rich sediments to isolated mounds. Simultaneously, the iron oxide concretions weat hered out to form lag deposits mostly at the base of scarps. During that time, some of the ILD may have become tilted by structural deformation. Alternatively, inclined beds on the mounds may have come from draping by volcanic ash or eolian deposits, or by gravity sliding on the steep, evaporite-charged flanks of the mounds. Inclined layers could be readily explained if the ILD were tuyas. Landslides fell into the newly created voids and occasional sliding persisted throughout most of the troughs' history. Minor volcanic activity continued and may have spewed mafic ash onto the eroded ILD-mound surfaces and onto the trough floors. Eventually, only wind persisted, producing yardangs on the ILD and reworking ash, trapped eolian sediments, and debris eroded from the ILD.
Miller, Todd S.; Karig, Daniel E.
2010-01-01
In 2002, the U.S. Geological Survey, in cooperation with the Tompkins County Planning Department began a series of studies of the stratified-drift aquifers in Tompkins County to provide geohydrologic data for planners to develop a strategy to manage and protect their water resources. This aquifer study in lower Sixmile Creek and Willseyville Creek trough is the second in a series of aquifer studies in Tompkins County. The study area is within the northern area of the Appalachian Plateau and extends about 9 miles from the boundary between Tompkins County and Tioga County in the south to just south of the City of Ithaca in the north. In lower Sixmile Creek and Willseyville Creek trough, confined sand and gravel aquifers comprise the major water-bearing units while less extensive unconfined units form minor aquifers. About 600 people who live in lower Sixmile Creek and Willseyville Creek trough rely on groundwater from the stratified-drift aquifer system. In addition, water is used by non-permanent residents such as staff at commercial facilities. The estimated total groundwater withdrawn for domestic use is about 45,000 gallons per day (gal/d) or 0.07 cubic foot per second (ft3/s) based on an average water use of 75 gal/d per person for self-supplied water systems in New York. Scouring of bedrock in the preglacial lower Sixmile Creek and Willseyville Creek valleys by glaciers and subglacial meltwaters truncated hillside spurs, formed U-shaped, transverse valley profiles, smoothed valley walls, and deepened the valleys by as much as 300 feet (ft), forming a continuous trough. The unconsolidated deposits in the study area consist mostly of glacial drift, both unstratified drift (till) and stratified drift (laminated lake, deltaic, and glaciofluvial sediments), as well as some post-glacial stratified sediments (lake-bottom sediments that were deposited in reservoirs, peat and muck that were deposited in wetlands, and alluvium deposited by streams). Multiple advances and retreats of the ice in the study area resulted in several sequences of various types of glacial deposits. A large moraine (Valley Heads Moraine) dominates the southern part of the study area, a large delta dominates the central part, and ground moraine (mostly till) dominates the northern part. Glacial sediments in the center of the lower Sixmile Creek and Willseyville Creek trough typically range from 150 to 200 ft but can be greater than 300 ft in some places. Where the sediments are composed of sand and gravel they form aquifers. In most parts of the lower Sixmile Creek and Willseyville Creek trough, there is an upper and a basal confined aquifer. However, underlying the central parts of the Brooktondale delta, there are as many as four confined aquifers, whereas in the northern part of the study area, only one extensive confined aquifer is present. The major sources of recharge to these confined aquifers are (1) direct infiltration of precipitation where confined aquifers crop out at land surface (mostly along the western trough wall in the southern and central parts of the study area and, to a lesser degree, along the eastern trough wall); (2) unchanneled surface and subsurface runoff from adjacent upland areas that seeps into the aquifer along the western trough walls; (3) subsurface flow from underlying till or bedrock at the lateral contacts at trough walls; (4) adjacent fine-grained stratified drift, especially when the aquifer is pumped; and (5) discharge from bedrock at the bottom and sides of the trough. In the central part of the study area, the surficial coarse-grained sediments (sand and gravel) comprise a delta near Brooktondale and form a small unconfined aquifer (0.3 square mile). Although much of the upper part of the delta has been removed by several aggregate mining operations, sufficient amounts of sand and gravel remain in most places to form a thin unconfined aquifer. The major sources of recharge to the unconfined aquifer are (1)
NASA Astrophysics Data System (ADS)
Breyer, Christian; Afanasyeva, Svetlana; Brakemeier, Dietmar; Engelhard, Manfred; Giuliano, Stefano; Puppe, Michael; Schenk, Heiko; Hirsch, Tobias; Moser, Massimo
2017-06-01
The main objective of this research is to present a solid foundation of capex projections for the major solar energy technologies until the year 2030 for further analyses. The experience curve approach has been chosen for this capex assessment, which requires a good understanding of the projected total global installed capacities of the major solar energy technologies and the respective learning rates. A literature survey has been conducted for CSP tower, CSP trough, PV and Li-ion battery. Based on the literature survey a base case has been defined for all technologies and low growth and high growth cases for further sensitivity analyses. All results are shown in detail in the paper and a comparison to the expectation of a potentially major investor in all of these technologies confirmed the derived capex projections in this paper.
Magnetic anomaly map of the central Cayman Trough, northwestern Caribbean Sea
Dillon, William P.; Edgar, N. Terence; Parson, Lindsay M.; Scanlon, Kathryn M.; Driscoll, George R.; Jacobs, Colin L.
1993-01-01
This is the first large-scale published map of magnetic anomalies in the central Cayman Trough area. Two previously published very small scale maps based on much less data are a regional map (Gough and Heirtzler, 1969) and a map compiled from several tracklines running parallel to the axis of the Cayman Trough (MacDonald and Holcombe, 1978).
USDA-ARS?s Scientific Manuscript database
The “See-Saw” is a vertical-lift incubator that increases water circulation around and through channel catfish egg masses. Baskets in the incubator move up and down on racks in conventional hatchery troughs, raising the rack in one trough while lowering the rack in the adjacent trough. Egg masses ...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Turchi, Craig; Kurup, Parthiv; Akar, Sertac
This study lists material composition data for two concentrating solar power (CSP) plant designs: a molten-salt power tower and a hypothetical parabolic trough plant, both of which employ a molten salt for the heat transfer fluid (HTF) and thermal storage media. The two designs have equivalent generating and thermal energy storage capacities. The material content of the saltHTF trough plant was approximately 25% lower than a comparably sized conventional oil-HTF parabolic trough plant. The significant reduction in oil, salt, metal, and insulation mass by switching to a salt-HTF design is expected to reduce the capital cost and LCOE for themore » parabolic trough system.« less
NASA Technical Reports Server (NTRS)
2005-01-01
1 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an impact crater cut by troughs which formed after the crater formed. The crater and troughs have large windblown ripples on their floors. The ripples, troughs, craters, and other surfaces in this scene have all been mantled by dust. Dark streaks on slopes indicate areas where avalanches of dry dust have occurred. These features are located on Sacra Mena, a large mesa in the Kasei Valles region. Location near: 25.4oN, 66.8oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern AutumnAeolian Sediment Transport Pathways and Aerodynamics at Troughs on Mars
NASA Technical Reports Server (NTRS)
Bourke, Mary C.; Bullard, Joanna E.; Barnouin-Jha, Olivier S.
2004-01-01
Interaction between wind regimes and topography can give rise to complex suites of aeolian landforms. This paper considers aeolian sediment associated wit11 troughs on Mars and identifies a wider range of deposit types than has previously been documented. These include wind streaks, falling dunes, "lateral" dunes, barchan dunes, linear dunes, transverse ridges, sand ramps, climbing dunes, sand streamers, and sand patches. The sediment incorporated into these deposits is supplied by wind streaks and ambient Planitia sources as well as originating within the trough itself, notably from the trough walls and floor. There is also transmission of sediment between dneTsh. e flow dynamics which account for the distribution of aeolian sediment have been modeled using two-dimensional computational fluid dynamics. The model predicts flow separation on the upwind side of the trough followed by reattachment and acceleration at the downwind margin. The inferred patterns of sediment transport compare well with the distribution of aeolian forms. Model data indicate an increase of wind velocity by approx. 30 % at the downwind trough margin. This suggests that the threshold wind speed necessary for sand mobilization on Mars will be more freqentmlye t in these inclined locations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jones, T.B.; Lester, M.; Wilkinson, A.J.
A statistical study of the F-region main ionospheric trough has been undertaken with EISCAT common programme data to assess the possibility that the trough region is a perferential region for the generation of E-region irregularities. Three years of CP-3 data from EISCAT formed the basis of this study. Backscatter observed by the coherent radar, SABRE, was also utilized to study the occurrence of irregularities in the E-region. On 26 out of the 36 days when the trough was observed by EISCAT, SABRE observed coherent backscatter. Although this percentage seems high, there was no consistent relationship between the latitude of themore » trough minimum and the latitude of peak backscatter intensity. A case study involving a four day run of EISCAT in September 1986 indicates that the trough latitude can be affected by changes in the interplanetary magnetic field north-south components. On two days rapid decreases in the latitude of the trough were related to a southward turning of the IMF and the onset of backscatter. The high percentage of occurrence of backscatter is believed to be caused by enhanced convection.« less
Crustal and upper mantle velocity structure of the Salton Trough, southeast California
Parsons, T.; McCarthy, J.
1996-01-01
This paper presents data and modelling results from a crustal and upper mantle wide-angle seismic transect across the Salton Trough region in southeast California. The Salton Trough is a unique part of the Basin and Range province where mid-ocean ridge/transform spreading in the Gulf of California has evolved northward into the continent. In 1992, the U.S. Geological Survey (USGS) conducted the final leg of the Pacific to Arizona Crustal Experiment (PACE). Two perpendicular models of the crust and upper mantle were fit to wide-angle reflection and refraction travel times, seismic amplitudes, and Bouguer gravity anomalies. The first profile crossed the Salton Trough from the southwest to the northeast, and the second was a strike line that paralleled the Salton Sea along its western edge. We found thin crust (???21-22 km thick) beneath the axis of the Salton Trough (Imperial Valley) and locally thicker crust (???27 km) beneath the Chocolate Mountains to the northeast. We modelled a slight thinning of the crust further to the northeast beneath the Colorado River (???24 km) and subsequent thickening beneath the metamorphic core complex belt northeast of the Colorado River. There is a deep, apparently young basin (???5-6 km unmetamorphosed sediments) beneath the Imperial Valley and a shallower (???2-3 km) basin beneath the Colorado River. A regional 6.9-km/s layer (between ???15-km depth and the Moho) underlies the Salton Trough as well as the Chocolate Mountains where it pinches out at the Moho. This lower crustal layer is spatially associated with a low-velocity (7.6-7.7 km/s) upper mantle. We found that our crustal model is locally compatible with the previously suggested notion that the crust of the Salton Trough has formed almost entirely from magmatism in the lower crust and sedimentation in the upper crust. However, we observe an apparently magmatically emplaced lower crust to the northeast, outside of the Salton Trough, and propose that this layer in part predates Salton Trough rifting. It may also in part result from migration of magmatic spreading centers associated with the southern San Andreas fault system. These spreading centers may have existed east of their current locations in the past and may have influenced the lower crust and upper mantle to the east of the current Salton Trough.
Fast flow of Jakobshavn Isbræ and its subglacial drainage system
NASA Astrophysics Data System (ADS)
Werder, M. A.; Joughin, I. R.
2013-12-01
Jakobshavn Isbræ and many other outlet glaciers of present and past ice sheets lie in deep troughs which often have several overdeepened sections. The subglacial drainage system of such glaciers is heavily influenced by two effects caused by the pressure dependence of the melting point of water. The melting point decreases with increasing water pressure, this enhances wall-melt in downward sloping channels and diminishes wall-melt in upward sloping channels. Thus the first effect is the well known shutdown of channels on steep adverse bed slopes of overdeepenings and the associated high water pressure/low effective pressure. The second effect is a 2D effect and has not received much/any attention so far: the orientation of a channel will be deflected from the direction of the (negative) hydraulic potential gradient (which drives the water flow) towards the steepest slope of the bed. This leads to the enhanced formation of side channels dipping into the trough at about a 45° angle. This efficient connection between the margin and the trough equalizes the hydraulic potential, again leading to higher water pressure in the trough. We investigate these two effects with the 2D subglacial drainage system model GlaDS using Jakobshavn Isbræ as an example. We compare model runs with the pressure melt term disabled and enabled. With the term disabled the main channel situated in the trough is continuous and produces a large depression in the hydraulic potential and consequently high effective pressure in the trough (1-2MPa). Conversely, with the term enabled the main channel becomes discontinuous on steep adverse bed slopes and many side channels form on the margins of the trough. This leads to a hydraulic potential in the trough which is higher than in the surrounding area and consequently the effective pressure is low (0-1MPa). Low effective pressure leads to reduced basal drag and thus to more basal sliding. The modeled large decrease of effective pressure in the trough due to the pressure dependence of the melting point of water suggests that basal drag will be small and that sliding speeds are large. Thus, this may be one of the leading causes for the fast flow of Jakobshavn Isbræ and other glaciers in deep troughs.
NASA Astrophysics Data System (ADS)
Oishi, Y.; Furumura, T.; Imamura, F.; Yamashita, K.; Sugawara, D.
2016-12-01
In this study, we investigate the response of bays to the tsunami of Nankai-trough earthquake based on tsunami simulations and demonstrate the possibility that sea-level oscillation of each bay, which is induced by an incident tsunami, interacts with those of other bays. Several major cities in Japan, including the capital, are located in the bays near the Nankai trough and it is assumed that these cities will be largely affected by the tsunamis caused by recurring large earthquakes at the trough. Therefore, it is very important for these populated cities to understand the mechanism and properties of the tsunami-induced oscillations that continue for a long time in bays to draw up evacuation plans. To investigate the response of bays for various tsunamis that may occur in the Nankai trough area, we distributed the tsunami sources that have the form of a 2-D Gaussian function around the Nankai trough. From simulations with these sources, it was found that strong oscillations of bay water occur when the source is located in the bay itself or when strong oscillations occur in other bays. For example, when the Tosa bay oscillates, the Tokyo bay that is 600 km away from the Tosa bay also oscillates. Among the bays around the Nankai trough, the Suruga bay, the deepest bay in Japan with a 2500-km depth, oscillates more strongly than other bays for most cases. To check the influence of the strong oscillations in the Suruga bay on other bays, we conducted tsunami simulations using a modified topography model in which the Suruga bay is artificially landfilled. As a consequence, the strength of oscillations in the adjacent bays are reduced by 20-30%, suggesting the large influence of the distinguished oscillation of the Suruga bay on these bays. We finally conducted tsunami simulations using the eleven Nankai-trough earthquake scenarios of the Central Disaster Prevention Council (CDPC) of Japan as tsunami sources, and the mutual relation regarding the strengths of oscillations among the bays around the Nankai trough was confirmed irrespective of the earthquake scenarios. The results of this study suggest that oscillations of the bays do not occur independently in each bay but simultaneously occur among the bays. More detailed characteristics of the response of the bays to the tsunamis in the Nankai-trough area will be discussed in the presentation.
Model based verification of the Secure Socket Layer (SSL) Protocol for NASA systems
NASA Technical Reports Server (NTRS)
Powell, John D.; Gilliam, David
2004-01-01
The National Aeronautics and Space Administration (NASA) has tens of thousands of networked computer systems and applications. Software Security vulnerabilities present risks such as lost or corrupted data, information theft, and unavailability of critical systems. These risks represent potentially enormous costs to NASA. The NASA Code Q research initiative 'Reducing Software Security Risk (RSSR) Trough an Integrated Approach' offers formal verification of information technology (IT), through the creation of a Software Security Assessment Instrument (SSAI), to address software security risks.
Controls of bioclastic turbidite deposition in eastern Muertos Trough northeast Caribbean Sea
DOE Office of Scientific and Technical Information (OSTI.GOV)
Forsthoff, G.M.; Holcombe, T.L.
1985-02-01
A study of seismic-reflection profiles and sediment cores establishes regional bathymetric and source area control over the composition, transport, and distribution of turbidites in the eastern Muertos Trough, Bioclastic (carbonate) turbidites dominate the eastern portion of the trough. Analyses of carbon content and sand-sized components suggest that the bioclastic turbidites (characterized by planktonic foraminifera, pteropods, and sponge spicules) are reworked pelagic oozes originally deposited on the outer-shelf and upper-slope areas south of St. Croix and eastern Puerto Rico. The presence of several intrashelf and upper-slope basins prohibits shallow-water carbonate sediments from entering the Muertos Trough. Volcanic rock fragments derived frommore » Puerto Rico are transported to the trough via the Guayanilla Canyon system. Mixing of the volcanic fragments with outer-shelf and upper-slope lutites results in mixed bioclastic-terrigenous turbidites south of central and western Puerto Rico. The paucity of shallow-water carbonate sediments in the trough suggests that the submarine canyons are effective conduits for the rapid transport of volcaniclastic sands across the shelf and thereby prevent extensive mixing with inner- and middle-shelf carbonate sediments. Sediment transport within the trough is primarily axial in an east-west direction. Outer trench-wall fault scarps, south of Guayanilla Canyon, limit the southerly progradation of the trench-wedge facies and deflect incoming gravity flows in a down-axis (westward) direction. Where no faults exist, the trench wedge progrades southward and interfingers with the pelagic sediments of the northern Venezuelan basin.« less
Weak lensing by galaxy troughs in DES Science Verification data
Gruen, D.; Friedrich, O.; Amara, A.; ...
2015-11-29
In this study, we measure the weak lensing shear around galaxy troughs, i.e. the radial alignment of background galaxies relative to underdensities in projections of the foreground galaxy field over a wide range of redshift in Science Verification data from the Dark Energy Survey. Our detection of the shear signal is highly significant (10σ–15σ for the smallest angular scales) for troughs with the redshift range z ϵ [0.2, 0.5] of the projected galaxy field and angular diameters of 10 arcmin…1°. These measurements probe the connection between the galaxy, matter density, and convergence fields. By assuming galaxies are biased tracers ofmore » the matter density with Poissonian noise, we find agreement of our measurements with predictions in a fiducial Λ cold dark matter model. The prediction for the lensing signal on large trough scales is virtually independent of the details of the underlying model for the connection of galaxies and matter. Our comparison of the shear around troughs with that around cylinders with large galaxy counts is consistent with a symmetry between galaxy and matter over- and underdensities. In addition, we measure the two-point angular correlation of troughs with galaxies which, in contrast to the lensing signal, is sensitive to galaxy bias on all scales. The lensing signal of troughs and their clustering with galaxies is therefore a promising probe of the statistical properties of matter underdensities and their connection to the galaxy field.« less
The Nova-Canton Trough and the Late Cretaceous evolution of the central Pacific
NASA Astrophysics Data System (ADS)
Joseph, Devorah; Taylor, Brain; Shor, Alexander N.; Yamazaki, Toshitsugu
Free-air gravity anomalies derived from satellite altimetry data show that the major Pacific fracture zones, from the Pau to Marquesas, are co-polar about an Euler pole located at 150.5°W, 34.6°S for the period preceding chron 33 and including a large portion of the Cretaceous Normal Superchron. They also show continuity of the Clipperton Fracture Zone through the Line Islands to the Nova-Canton ridge and trough; this Canton-Clipperton trend is co-polar to the same pole. Sidescan-sonar and bathymetry data in the Nova-Canton Trough region reveal N140°E-striking abyssal hill topography south of the N70°E-striking structures of the Nova-Canton Trough and crustal fabric striking normal to the trough (N160°E) to the north. We conclude that the Nova-Canton Trough is the Middle Cretaceous extension of the Clipperton Fracture Zone. We propose that the anomalous depths (7000-8400 m) of the trough between 167°30'-168°30'W are the result of a complex plate reorganization. Conjugate magnetic anomaly lineations M1-M3 in the Phoenix lineations between the Central Pacific Fracture Zone and the Phoenix Fracture Zone and the absence of lineations younger than anomaly M3 west of the Phoenix Fracture Zone suggest that spreading may have gradually ceased along the Pacific-Phoenix system from west to east. We infer that the remaining active segment of the Pacific-Phoenix spreading system after anomaly M1 time was the easternmost section of the Phoenix lineations. At ˜M0 time, the Pacific-Phoenix spreading axis stretched from lineated bathymetric depressions lying between 180°W and the Phoenix Islands to ˜168°W and included the western deep of the Nova-Canton Trough. We hypothesize that accretion terminated on the Pacific-Phoenix spreading axis shortly after M0 time and that the absence of an M0 isochron in the region between the eastern Phoenix lineations and the Nova-Canton Trough, or along the Nova-Canton Trough itself, may be due to a decrease in spreading rate prior to termination. We concur with previous hypotheses that portions of the Phoenix plate were trapped on the Pacific plate by a ridge jump south to the nascent Manihiki Plateau; some portions were overprinted by the Aptian volcanism that formed the Manihiki Plateau and Robbie Ridge. Pacific-Farallon spreading south of the Nova-Canton Trough jumped westwards, initiating transcurrent motion along the easternmost section of the failed ˜M0 spreading axis (the western deep of the Nova-Canton Trough) which subsequently became the western end of the Clipperton (Pacific-Farallon) transform. In our reconstruction, the northeast and southeast margins of the Manihiki Plateau are rifted margins that form the western limit of Pacific-Farallon spreading between the Clipperton, Galapagos, and Marquesas fracture zones.
Xu, Y; Li, YF; Zhang, D; Dockendorf, M; Tetteh, E; Rizk, ML; Grobler, JA; Lai, M‐T; Gobburu, J
2016-01-01
We applied model‐based meta‐analysis of viral suppression as a function of drug exposure and in vitro potency for short‐term monotherapy in human immunodeficiency virus type 1 (HIV‐1)‐infected treatment‐naïve patients to set pharmacokinetic targets for development of nonnucleoside reverse transcriptase inhibitors (NNRTIs) and integrase strand transfer inhibitors (InSTIs). We developed class‐specific models relating viral load kinetics from monotherapy studies to potency normalized steady‐state trough plasma concentrations. These models were integrated with a literature assessment of doses which demonstrated to have long‐term efficacy in combination therapy, in order to set steady‐state trough concentration targets of 6.17‐ and 2.15‐fold above potency for NNRTIs and InSTIs, respectively. Both the models developed and the pharmacokinetic targets derived can be used to guide compound selection during preclinical development and to predict the dose–response of new antiretrovirals to inform early clinical trial design. PMID:27171172
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li Junfeng; Zhu Li; Liu Zhan
1998-07-01
At the request of US sponsors Spencer Management Associates (SMA) and Sun{diamond}Lab, China`s Center for Renewable Energy Development and former Ministry of Electric Power conducted an initial appraisal of the issues involved with developing China`s first solar thermal electric power plant in the sunbelt regions of Tibet or Xinjiang provinces. The appraisal concerns development of a large-scale, grid-connected solar trough or tower project capable of producing 30 or more megawatts of electricity. Several of the findings suggest that Tibet could be a niche market for solar thermal power because a solar plant may be the low-cost option relative to othermore » methods of generating electricity. China has studied the concept of a solar thermal power plant for quite some time. In 1992, it completed a pre-feasibility study for a SEGS-type parabolic trough plant with the aid of Israel`s United Development Limited. Because the findings were positive, both parties agreed to conduct a full-scale feasibility study. However, due to funding constraints, the study was postponed. Most recently, Sun{diamond}Lab and SMA asked China to broaden the analysis to include tower as well as trough concepts. The findings of this most recent investigation completed i November of 1997, are the subject of this paper. The main conclusions of all studies conducted to date suggest that a region in the proximity of Lhasa, Tibet, offers the best near-term opportunity within China. The opportunities for solar thermal power plants in other regions of China were also investigated.« less
Galindo, Danielle; Villanueva, Linda; Nguyen, Cathy; Patel, Milan; Borbridge, Lisa; Attar, Mayssa; Schiffman, Rhett M.; Hollander, David A.
2011-01-01
Abstract Purpose Anti-inflammatory activity of topical nonsteroidal anti-inflammatory drugs is mediated by suppression of cyclooxygenase (COX) isoenzymes. This study compared ocular penetration and inflammation suppression of topical ketorolac 0.45% and bromfenac 0.09% ophthalmic solutions in a rabbit model. Methods At hour 0, 36 rabbits received ketorolac 0.45%, bromfenac 0.09%, or an artificial tear 3 times once every 20 min. Half of the rabbits in each group then received intravenous injections of lipopolysaccharide (LPS) and fluorescein isothiocyanate (FITC)–dextran at hour 1, and the other half at hour 10. Aqueous and iris-ciliary body (ICB) samples were collected in the former group at hour 2 (peak) and in the latter group at hour 11 (trough) An additional group of 6 animals received only FITC-dextran, and samples were collected 1 h later. Peak and trough nonsteroidal anti-inflammatory drug concentrations were compared with previously determined half-maximal inhibitory concentrations (IC50) for COX isoenzymes. Results Peak and trough aqueous and ICB concentrations of ketorolac were at least 7-fold or greater than those of bromfenac. At peak levels, both ketorolac 0.45% and bromfenac 0.09% significantly inhibited LPS-induced aqueous prostaglandin E2 and FITC-dextran elevation (P < 0.01). At trough, both study drugs significantly inhibited LPS-induced aqueous prostaglandin E2 elevation (P < 0.05), but only ketorolac 0.45% significantly reduced LPS-induced aqueous FITC-dextran elevation (P < 0.01). Aqueous and ICB ketorolac concentrations exceeded its IC50 for COX-1 and COX-2 at peak and trough. Aqueous and ICB bromfenac levels exceeded its IC50 for COX-2 at peak and trough, but not for COX-1 at trough aqueous levels and peak and trough ICB levels. Conclusions Both ketorolac 0.45% and bromfenac 0.09% effectively suppressed inflammation at peak. At trough, only ketorolac 0.45% effectively suppressed inflammation as measured by FITC-dextran leakage. The difference in inflammation suppression may be due to differences in tissue concentrations and/or greater COX-1 suppression by ketorolac 0.45%. PMID:21351868
Formation of Continental Fragments: The Tamayo Bank, Gulf of California
NASA Astrophysics Data System (ADS)
van Wijk, J.; Abera, R.; Axen, G. J.
2015-12-01
Potential field data are used to construct a two-dimensional crustal model along a profile through the Tamayo Trough and Bank in the Gulf of California. The model is constrained by seismic reflection and refraction data, and field observations. The potential field data do not fit a model where the crust of the Tamayo trough is continental, but they fit well with a model where the Tamayo trough crust is oceanic. This implies that the Tamayo Bank is entirely bounded by oceanic crust and is a microcontinent. The oceanic crust of the Tamayo trough that separates the Tamayo Bank from the mainland of Mexico is thin (~4 km), so oceanic spreading was probably magma-starved before it ceased. This led us to come up with a model that explains the formation of microcontinents that are smaller in size and are not found in the proximity of hotspots. At first, seafloor spreading commences following continental breakup. When the magma supply to the ridge slows down, the plate boundary strengthens. Hence, the ridge may be abandoned while tectonic extension begins elsewhere, or slow spreading may continue while a new ridge starts to develop. The old spreading ridge becomes extinct. An asymmetric ocean basin forms if the ridge jumps within oceanic lithosphere; a microcontinent forms if the ridge jumps into a continental margin. This model for formation of continental fragments is applicable to other regions as well, eliminating the need of mantle plume impingement to facilitate rifting of a young continental margin and microcontinent formation.
NASA Astrophysics Data System (ADS)
Klimenko, M. V.; Klimenko, V. V.; Bryukhanov, V. V.
2007-05-01
In the given work the numerical calculation results of ionospheric effects of four modeling substorms which have begun in 00, 06, 12 and 18 UT are presented. Calculations are executed on the basis of Global Self-consistent Model of the Thermosphere, Ionosphere and Protonosphere (GSM TIP), developed in WD IZMIRAN, added by the new block of calculation of electric fields in the ionosphere of the Earth for vernal equinox conditions in the minimum of solar activity. In calculations we considered superposition of magnetospheric convection electric field (at set potential differences through polar caps and field aligned currents of the second zone with taking into account of particle precipitation) and dynamo field generated by thermospheric winds without taking into account the tides. It is shown, that in the given statement of problem the substorms cause strong positive disturbances in F-region of ionosphere in night sector. Negative disturbances are much less and arise, mainly, at night in the middle and low latitudes. During substorms longitudinal extent of main ionospheric trough increases. The substorm beginning in 18 UT, causes negative disturbances in high latitudes except for a southern polar cap. Besides there is "stratification" of the main ionospheric trough. As a result in southern hemisphere the additional high-latitude trough which is absent in quiet conditions is formed. "Stratification" of the main ionospheric trough occurs in northern hemisphere at 6 hours after the beginning of the substorm. These "stratifications" are consequence non-stationary magnetospheric convection. Distinction between these events consists that "stratification" in a southern hemisphere occurs in active phase of substorm, and in northern hemisphere in recovery phase. During a substorm beginning in 00 UT, foF2 increases in all northern polar cap. Positive disturbances of foF2 in the equatorial anomaly region cause all presented substorms, except for a substorm beginning in 18 UT. This substorm causes small negative disturbances in the equatorial anomaly region in the Indian longitudinal sector.
Altitude Variation of the Plasmapause Signature in the Main Ionospheric Trough
NASA Technical Reports Server (NTRS)
Grebowsky, Joseph M.; Benson, Robert F.; Webb, Phillip A.; Truhlik, Vladimir; Bilitza, Dieter
2009-01-01
The projection of the plasmapause magnetic-field lines to low altitudes, where the light-ion chemistry is dominated by O(+), tends to occur near the minimum electron density in the main (midlatitude) electron density trough at night. With increasing attitude in the trough, where H(+) emerges as the dominant iota on the low-latitude boundary, we have found cases where the plasmapause field lines are located on the sharp low-Latitude side of the trough as expected if this topside ionosphere H(+) distribution varies in step with the plasmapause gradient in the distant plasmasphere. These conclusions are based on near-equatorial crossings of the plasmapause (corresponding to the steep gradient in the dominant species H(+) by the Explorer-45 satellite as determined from electric-field measurements by Maynard and Cauffman in the early 1970s and ISIS-2 ionospheric topside-sounder measurements. The former data have now been converted to digital form and made available at http://nssdcftp.gsfc.nasa.gov. The latter provide samples of nearly coincident observations of ionospheric main trough crossings near the same magnetic-field lines of the Explorer 45-determined equatorial plasmapause. The ISIS-2 vertical electron density profiles are used to infer where the F-region transitions from an O(+) to a H(+) dominated plasma through the main trough boundaries.
Use of rapid prototyping drill template for the expansive open door laminoplasty: A cadaveric study.
Rong, Xin; Wang, Beiyu; Chen, Hua; Ding, Chen; Deng, Yuxiao; Ma, Lipeng; Ma, Yanzhao; Liu, Hao
2016-11-01
Trough preparation is a technically demanding yet critical procedure for successful expansive open door laminoplasty (EOLP), requiring both proper position and appropriate bone removal. We aimed to use the specific rapid prototyping drill template to achieve such requirement. The 3D model of the cadaveric cervical spine was reconstructed using the Mimics 17.0 and Geomagic Studio 12.0 software. The drilling template was designed in the 3-Matic software. The trough position was simulated at the medial margin of the facet joint. Two holders were designed on both sides. On the open side, the holder would just allow the drill penetrate the ventral cortex of the lamina. On the hinge side, the holder was designed to keep the ventral cortex of the lamina intact. One orthopedic resident performed the surgery using the rapid prototyping drill template on four cadavers (template group). A control group of four cadavers were operated upon without the use of the template. The deviation of the final trough position from the simulated trough position was 0.18mm±0.51mm in the template group. All the troughs in the template group and 40% of the troughs in the control group were at the medial side of the facet joint. The complete hinge fracture rate was 5% in the template group, significantly lower than that (55%) in the control group (P=0.01). The rapid prototyping drill template could help the surgeon accomplish proper trough position and appropriate bone removal in EOLP on the cadaveric cervical spine. Copyright © 2016 Elsevier B.V. All rights reserved.
Petroleum prospects of Benue trough, Nigeria
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nawachukwu, J.I.
1985-04-01
Exploration activities in the Benue trough have been minimal over the years, mainly because of large petroleum deposits found in the adjoining Niger delta and early gas finds in the Anambra basin, south of the Benue trough. The recent increase in exploration activities in the trough has necessitated a reevaluation of the petroleum potentials of the basin. In this study, the time-temperature index (TTI) method was used to evaluate petroleum prospects of the basin. An increase in geothermal gradient resulted in a decrease in depth to the oil window, with the sediments maturing earlier at higher geothermal gradients. At geothermalmore » gradients of 1.5-1.9/sup 0/F/100 ft (2.73.5/sup 0/C/100 m) and maximum TTI values, the Asu River Group and the Eze-Aku Group of sediments are still within the gas-generating stage. The Awgu Shale and the Nkporo Shale are capable of generating gas at geothermal gradients of 2.3-2.7/sup 0/F/100 ft (4.2-4.9/sup 0/C/100 m). The Benue trough is essentially a gas-condensate basin with little oil. Exploration targets in the basin include both the sub-Santonian and superSantonian sediments, with the Eze-Aku Group, Awgu Shale, and Nkporo Shale being more prospective than the stratigraphically lower Asu River Group. In general, the middle Benue trough is considered to be the most prospective area within the trough because depths to the mature zones are moderate (6,600-13,000 ft; 2-4 km). These depths are variable, decreasing northeastward and increasing southwestward toward the Niger delta.« less
Shin, Hyoshim; Cho, Min-Chul; Kim, Rock Bum; Kim, Chang-Hun; Choi, Nack-Cheon; Kim, Soo-Kyung; Koh, Eun-Ha
2018-02-01
Apixaban is effective and safe for preventing stroke, and its usage has increased exponentially in recent years. However, data concerning the therapeutic range of apixaban is limited. This study determined the trough and peak levels of apixaban-specific anti-factor Xa activity (AFXaA) in acute ischemic stroke patients with non-valvular atrial fibrillation (NVAF) in Korea. The study included 85 patients who received apixaban. Blood samples were taken to measure the trough and peak levels of AFXaA using a chromogenic anti-factor assay, as well as prothrombin time (PT) and activated partial thromboplastin time (aPTT). We also reviewed complications such as major bleeding of patients treated with apixaban. In patients given a 5.0-mg apixaban dose, the median trough and peak levels of AFXaA were 104.5 and 202.0 ng/mL. In patients given a 2.5-mg apixaban dose, the median trough and peak AFXaA levels were 76.0 and 151.0 ng/mL. The PT showed a positive correlation with increased AFXaA activity at both levels (Trough R = 0.486, Peak R = 0.592), but the aPTT had no relationship with AFXaA activity at both levels (Trough R = 0.181, Peak R = 0.129). Two cases with intracranial bleeding belonged to the highest AFXaA quartile (Trough, p = 0.176; Peak, p = 0.053). In conclusion, we determined the trough and peak levels of AFXaA in patients with NVAF while being treated with the apixaban in Korea. Our results could be used as a starting point when setting the reference ranges for laboratories using anti-Xa assay. Large-scale studies are needed to establish the reference range for AFXaA in patients with NVAF.
Yacoub, W; Williet, N; Pouillon, L; Di-Bernado, T; De Carvalho Bittencourt, M; Nancey, S; Lopez, A; Paul, S; Zallot, C; Roblin, X; Peyrin-Biroulet, L
2018-04-01
The correlation between vedolizumab trough levels during induction therapy and mucosal healing remains unknown. To compare early vedolizumab trough levels in patients with and without mucosal healing within the first year after treatment initiation. We prospectively collected vedolizumab trough levels in all inflammatory bowel disease patients at weeks 2, 6 and 14 of vedolizumab treatment in three French referral centres between 1 June 2014 and 31 March 2017. Results of every patient that underwent mucosal assessment by magnetic resonance imaging and/or endoscopy in the first year after treatment initiation were analysed. Median vedolizumab trough levels in the overall population (n = 82) were 27 μg/mL (interquartile range, IQR 21.2-33.8 μg/mL) at week 2, 23 μg/mL (IQR 15-34.5 μg/mL) at week 6 and 10.7 μg/mL (IQR 4.6-20.4 μg/mL) at week 14. Only median vedolizumab trough levels at week 6 differed between patients with and without mucosal healing within the first year after treatment initiation (26.8 vs 15.1 μg/mL, P = 0.035). A cut-off trough level of 18 μg/mL at week 6 predicted mucosal healing within the first year after the start of vedolizumab with an area under the receiver operating curve of 0.735 (95% confidence interval 0.531-0.939). A vedolizumab trough level above 18 μg/mL at week 6 was the only independent variable associated with mucosal healing within the first year of treatment (odds ratio 15.7, 95% confidence interval 2.4-173.0, P = 0.01). Early therapeutic drug monitoring might improve timely detection of vedolizumab-treated patients in need for an intensified dosing regimen. © 2018 John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
Otieno, George A.; Loosen, Alexander E.
2016-05-01
Concentrated Solar Power projects have impacts on local environment and social conditions. This research set out to investigate the environmental and social risks in the development of such projects and rank these risks from highest to lowest. The risks were analysed for parabolic trough and tower technologies only. A literature review was undertaken, identifying seventeen risks that were then proposed to six CSP experts for scoring. The risks were scored based of five factors on a five tier scale. The scores from the experts were compiled to develop an overall rank of the identified risks. The risk of disruption of local water resources was found to represent the highest risk before and after mitigation with a score of moderate-high and moderate respectively. This score is linked to the importance of water in water scarce regions typified by the best regions for CSP. The risks to avian species, to worker health and safety, due to noise on the environment, to visual and recreational resources completed the top five risks after mitigation.
Design of a nanopatterned long focal-length planar focusing collector for concentrated solar power
NASA Astrophysics Data System (ADS)
Ding, Qing; Choubal, Aakash; Toussaint, Kimani C.
2017-02-01
Concentrated solar power (CSP) facilities heavily utilize parabolic troughs to collect and concentrate sunlight onto receivers that deliver solar thermal energy to heat engines for generating electricity. However, parabolic troughs are bulky and heavy and result in a large capital investment for CSP plants, thereby making it difficult for CSP technology to be competitive with photovoltaics. We present the design of a planar focusing collector (PFC) with focal length beyond the micron scale. The PFC design is based on the use of a nanostructured silver surface for linearly polarized singlewavelength light. The designed PFC consists of metallic nanogrooves on a dielectric substrate. The geometric properties, namely the width and depth, of a single-unit nanogroove allows for full control of the optical phase at desired spatial coordinates along the nanogroove short-axis for a single wavelength. Moreover, we show numerically that such phase control can be used to construct a phase front that mimics that of a cylindrical lens. In addition, we determine the concentration ratio by comparing the width of our PFC design to the cross-sectional width of its focal spot. We also determine the conversion efficiency at long focal lengths by evaluating the ratio of the collected optical power to the incoming optical power. Finally, we examine the focusing behavior across multiple wavelengths and angles of incidence. Our work shows how nano-optics and plasmonics could contribute to this important area of CSP technology.
Projection of distributed-collector solar-thermal electric power plant economics to years 1990-2000
NASA Technical Reports Server (NTRS)
Fujita, T.; Elgabalawi, N.; Herrera, G.; Turner, R. H.
1977-01-01
A preliminary comparative evaluation of distributed-collector solar thermal power plants was undertaken by projecting power plant economics of selected systems to the 1990 to 2000 time frame. The selected systems include: (1) fixed orientation collectors with concentrating reflectors and vacuum tube absorbers, (2) one axis tracking linear concentrator including parabolic trough and variable slat designs, and (3) two axis tracking parabolic dish systems including concepts with small heat engine-electric generator assemblies at each focal point as well as approaches having steam generators at the focal point with pipeline collection to a central power conversion unit. Comparisons are presented primarily in terms of energy cost and capital cost over a wide range of operating load factors. Sensitvity of energy costs for a range of efficiency and cost of major subsystems/components is presented to delineate critical technological development needs.
Evidence and mechanism of Hurricane Fran-Induced ocean cooling in the Charleston Trough
NASA Astrophysics Data System (ADS)
Xie, Lian; Pietrafesa, L. J.; Bohm, E.; Zhang, C.; Li, X.
Evidence of enhanced sea surface cooling during and following the passage of Hurricane Fran in September 1996 over an oceanic depression located on the ocean margin offshore of Charleston, South Carolina (referred to as the Charleston Trough), [Pietrafesa, 1983] is documented. Approximately 4C° of sea surface temperature (SST) reduction within the Charleston Trough following the passage of Hurricane Fran was estimated based on SST imagery from Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-14 polar orbiting satellite. Simulations using a three-dimensional coastal ocean model indicate that the largest SST reduction occurred within the Charleston Trough. This SST reduction can be explained by oceanic mixing due to storm-induced internal inertia-gravity waves.
NASA Astrophysics Data System (ADS)
Tsuboi, Seiji; Horikawa, Hiroki; Takaesu, Morifumi; Sueki, Kentaro; Araki, Eiichiro; Sonoda, Akira; Takahashi, Narumi
2016-04-01
The Nankai Trough in southwest Japan is one of most active subduction zone in the world. Great mega-thrust earthquakes repeatedly occurred every 100 to 150 years in this area, it's anticipated to occur in the not distant future. For the purpose of elucidation of the history of mega-splay fault activity, the physical properties of the geological strata and the internal structure of the accretionary prism, and monitoring of diastrophism in this area, we have a plan, Nankai Trough Seismogenic Zone Experiments (NanTroSEIZE), as a part of Integrated Ocean Drilling Program (IODP). We have a plan to install the borehole observation system in a few locations by the NanTroSEIZE. This system is called Long-Term Borehole Monitoring System, it consists of various sensors in the borehole such as a broadband seismometer, a tiltmeter, a strainmeter, geophones and accelerometer, thermometer array as well as pressure ports for pore-fluid pressure monitoring. The signal from sensors is transmitted to DONET (Dense Ocean-floor Network System for Earthquake and Tsunamis) in real time. During IODP Exp. 332 in December 2010, the first Long-Term Borehole Monitoring System was installed into the C0002 borehole site located 80 km off the Kii Peninsula, 1938 m water depth in the Nankai Trough. We have developed a web application system for data download, Long-Term Borehole Monitoring Data Site. Based on a term and sensors which user selected on this site, user can download monitoring waveform data (e.g. broadband seismometer data, accelerometer data, strainmeter data, tiltmeter data) in near real-time. This system can make the arbitrary data which user selected a term and sensors, and download it simply. Downloadable continuous data is provided in seed format, which includes sensor informations. In addition, before data download, user can check that data is abailable or not by data check function. In this presentation, we show our web application system and discuss our future plans for developments of monitoring data download system.
NASA Astrophysics Data System (ADS)
Glen, R. A.
The Palaeozoic history of the western part of the Lachlan Fold Belt in New South Wales was dominated by strike-slip tectonics. In the latest Silurian to late Early Devonian, an area of crust >25,000 km 2 lying west of the Gilmore Suture underwent regional sinistral transtension, leading to the development of intracratonic successor basins, troughs and flanking shelves. The volcaniclastic deep-water Mount Hope Trough and Rast Trough, the siliciclastic Cobar Basin and the volcanic-rich Canbelego-Mineral Hill Belt of the Kopyje Shelf all were initiated around the Siluro-Devonian boundary. They all show clear evidence of having evolved by both active syn-rift processes and passive later post-rift (sag-phase) processes. Active syn-rift faulting is best documented for the Cobar Basin and Mount Hope Trough. In the former case, the synchronous activity on several fault sets suggests that the basin formed by sinistral transtension in response to a direction of maximum extension oriented NE-SW. Structures formed during inversion of the Cobar Basin and Canbelego-Mineral Hill Belt indicate closure under a dextral transpressive strain regime, with a far-field direction of maximum shortening oriented NE-SW. In the Cobar Basin, shortening was partitioned into two structural zones. A high-strain zone in the east was developed into a positive half-flower structure by re-activation of early faults and by formation of short-cut thrusts, some with strike-slip movement, above an inferred steep strike-slip fault. Intense subvertical cleavage, a steep extension lineation and variably plunging folds are also present. A lower-strain zone to the west developed by syn-depositional faults being activated as thrusts soling into a gently dipping detachment. A subvertical cleavage and steep extension lineation are locally present, and variably plunging folds are common. Whereas Siluro-Devonian basin-opening appeared to be synchronous in the western part of the fold belt, the different period of basin inversion in the Cobar region (late Early Devonian and Carboniferous) may reflect different movement histories on the master strike-slip faults in this part of the fold belt, the Gilmore Suture and Kiewa Fault.
Dillon, William P.; Schlee, J.S.; Klitgord, Kim D.
1988-01-01
The continental margin of eastern North America was initiated when West Africa and North America were rifted apart in Triassic-Early Jurassic time. Cooling of the crust and its thinning by rifting and extension caused subsidence. Variation in amounts of subsidence led to formation of five basins. These are listed from south to north. (1) The Blake Plateau Basin, the southernmost, is the widest basin and the one in which the rift-stage basement took longest to form. Carbonate platform deposition was active and persisted until the end of Early Cretaceous. In Late Cretaceous, deposition slowed while subsidence persisted, so a deep water platform was formed. Since the Paleocene the region has undergone erosion. (2) The Carolina Trough is narrow and has relatively thin basement, on the basis of gravity modeling. The two basins with thin basement, the Carolina Trough and Scotian Basin, also show many salt diapirs indicating considerable deposition of salt during their early evolution. In the Carolina Trough, subsidence of a large block of strata above the flowing salt has resulted in a major, active normal fault on the landward side of the basin. (3) The Baltimore Canyon Trough has an extremely thick sedimentary section; synrift and postrift sediments exceed 18 km in thickness. A Jurassic reef is well developed on the basin's seaward side, but post-Jurassic deposition was mainly non-carbonate. In general the conversion from carbonate to terrigenous deposition, characteristics of North American Basins, occurred progressively earlier toward the north. (4) The Georges Bank Basin has a complicated deep structure of sub-basins filled with thick synrift deposits. This may have resulted from some shearing that occurred at this offset of the continental margin. Postrift sediments apparently are thin compared to other basins-only about 8 km. (5) The Scotian Basin, off Canada, contains Jurassic carbonate rocks, sandstone, shale and coal covered by deltaic deposits and Upper Cretaceous deeper water chalk and shale. ?? 1988.
NASA Astrophysics Data System (ADS)
Wang, Zhong-liang; Yamada, Masatoshi
2005-05-01
Plutonium concentrations and 240Pu/ 239Pu atom ratios in the East China Sea and Okinawa Trough sediment cores were determined by isotope dilution inductively coupled plasma mass spectrometry after separation using ion-exchange chromatography. The results showed that 240Pu/ 239Pu atom ratios in the East China Sea and Okinawa Trough sediments, ranging from 0.21 to 0.33, were much higher than the reported value of global fallout (0.18). The highest 240Pu/ 239Pu ratios (0.32-0.33) were observed in the deepest Okinawa Trough sediment samples. These ratios suggested the US nuclear weapons tests in the early 1950s at the Pacific Proving Grounds in the Marshall Islands were a major source of plutonium in the East China Sea and Okinawa Trough sediments, in addition to the global fallout source. It was proposed that close-in fallout plutonium was delivered from the Pacific Proving Grounds test sites via early direct tropospheric fallout and transportation by the North Pacific Equatorial Circulation system and Kuroshio Current into the Okinawa Trough and East China Sea. The total 239 + 240 Pu inventories in the cores were about 150-200% of that expected from direct global fallout; about 46-67% of the total inventories were delivered from the Pacific Proving Grounds. Much higher 239 + 240 Pu inventories were observed in the East China Sea sediments than in sediments of the Okinawa Trough, because in the open oceans, part of the 239 + 240 Pu was still retained in the water column, and continued Pu scavenging was higher over the margin than the trough. According to the vertical distributions of 239 + 240 Pu activities and 240Pu/ 239Pu atom ratios in these cores, it was concluded that sediment mixing was the dominant process in controlling profiles of plutonium in this area. Faster mixing in the coastal samples has homogenized the entire 240Pu/ 239Pu ratio record today; slightly slower mixing and less scavenging in the Okinawa Trough have left the surface sediment ratios closer to the modern North Pacific water end member and higher ratios (0.30-0.34) at the bottom of the cores.
Calza, L; Colangeli, V; Magistrelli, E; Bussini, L; Conti, M; Ramazzotti, E; Mancini, R; Viale, P
2017-08-01
The aim of the study was to assess plasma concentrations of darunavir/ritonavir and raltegravir in older patients compared with younger patients with HIV-1 infection. In this observational, open-label study, adult HIV-infected out-patients aged ≤ 40 years (younger patients) or ≥ 60 years (older patients) and treated with tenofovir/emtricitabine plus darunavir/ritonavir (800/100 mg daily) or raltegravir (400 mg twice daily) were asked to participate. The trough concentrations (C trough ) of darunavir/ritonavir and raltegravir were assessed at steady state using a validated high-performance liquid chromatography (HPLC)-tandem mass spectrometry method. A total of 88 HIV-positive patients were enrolled in the study. Forty-six patients were treated with darunavir/ritonavir, and 42 with raltegravir. The geometric mean plasma C trough (coefficient of variation) of raltegravir was comparable between the 19 older and 23 younger subjects: 106 ng/mL (151%) and 94 ng/mL (129%), respectively [geometric mean ratio (GMR) 0.85; 95% confidence interval (CI) 0.71-1.57; P = 0.087]. In contrast, the geometric mean plasma C trough of darunavir was significantly higher among the 21 older patients [2209 ng/mL (139%)] than among the 25 younger patients [1876 ng/mL (162%); GMR 1.56; 95% CI: 1.22-1.88; P = 0.004]. Similarly, the geometric mean C trough of ritonavir was significantly higher among older than among younger individuals. The mean plasma C trough of darunavir and ritonavir was significantly higher in older patients than in younger patients with HIV-1 infection, while the mean plasma level of raltegravir was comparable in the two groups. However, both regimens showed good tolerability in both younger and older subjects. © 2017 British HIV Association.
McNeil, J Chase; Kok, Eric Y; Forbes, Andrea; Lamberth, Linda; Hulten, Kristina G; Vallejo, Jesus G; Mason, Edward O; Kaplan, Sheldon L
2015-01-01
Introduction Elevated vancomycin MICs in S. aureus have been associated with worse clinical outcomes in adults. For invasive MRSA infections in adults, the IDSA recommends targeting vancomycin serum trough concentrations between 15–20 μg/ml. We evaluated trends in vancomycin MICs from healthcare-associated S. aureus bacteremia isolates in children in addition to correlating vancomycin serum trough levels with clinical outcomes. Methods Patients and isolates were identified from a prospective S. aureus surveillance study at Texas Children's Hospital (TCH). Healthcare-associated S. aureus bacteremia isolates from 2003–2013 were selected. Vancomycin MICs by E-test were determined and medical records were reviewed. Acute kidney injury (AKI) was defined as doubling of the baseline serum creatinine. Results 341 isolates met inclusion criteria. We observed a reverse vancomycin creep among MRSA isolates in the study period with a decline in the proportion of isolates with vancomycin MIC ≥ 2 μg/ml (from 32.7% to 5.6%, p<0.001). However, the proportion of MSSA isolates with MIC ≥ 2 μg/ml increased (from 2.9% to 9%, p=0.04). Among patients who had vancomycin troughs performed, there was no difference in duration of bacteremia or fever with vancomycin trough >15 μg/ml vs. < 15 μg/ml. A vancomycin trough > 15 μg/ml was, however, an independent risk factor for AKI. Conclusions Vancomycin MICs are shifting among healthcare-associated S. aureus bacteremia isolates with significant differences between MRSA and MSSA at TCH. Higher vancomycin troughs did not improve outcomes in pediatric healthcare-associated S. aureus bacteremia but were associated with increased nephrotoxicity. Further studies are needed to better understand optimal management of children with S. aureus bacteremia. PMID:26646549
Habitat use by larval fishes in a temperate South African surf zone
NASA Astrophysics Data System (ADS)
Watt-Pringle, Peter; Strydom, Nadine A.
2003-12-01
Larval fishes were sampled in the Kwaaihoek surf zone on the south east coast of South Africa. On six occasions between February and May 2002, larval fishes were collected in two habitat types identified in the inner surf zone using a modified beach-seine net. The surf zone habitats were classified as either sheltered trough areas or adjacent exposed surf areas. Temperature, depth and current measurements were taken at all sites. Trough habitats consisted of a depression in surf topography characterised by reduced current velocities and greater average depth than adjacent surf areas. In total, 325 larval fishes were collected. Of these, 229 were collected in trough and 96 in surf habitats. At least 22 families and 37 species were represented in the catch. Dominant families were the Mugilidae, Sparidae, Atherinidae, and Engraulidae. Dominant species included Liza tricuspidens and Liza richardsonii (Mugilidae), Rhabdosargus holubi and Sarpa salpa (Sparidae), Atherina breviceps (Atherinidae) and Engraulis japonicus (Engraulide). Mean CPUE of postflexion larvae of estuary-dependent species was significantly greater in trough areas. The proportion of postflexion larval fishes in trough habitat was significantly greater than that of preflexion stages, a result that was not apparent in surf habitat sampled. CPUE of postflexion larvae of estuary-dependent fishes was negatively correlated with current magnitude and positively correlated with habitat depth. Mean body length of larval fishes was significantly greater in trough than in surf habitats. These results provide evidence that the CPUE of postflexion larvae of estuary-dependent fishes is higher in trough habitat in the surf zone and this may be indicative of active habitat selection for areas of reduced current velocity/wave action. The implications of this behaviour for estuarine recruitment processes are discussed.
Impact of Month of Birth on the Risk of Development of Autoimmune Addison's Disease.
Pazderska, Agnieszka; Fichna, Marta; Mitchell, Anna L; Napier, Catherine M; Gan, Earn; Ruchała, Marek; Santibanez-Koref, Mauro; Pearce, Simon H
2016-11-01
The pathogenesis of autoimmune Addison's disease (AAD) is thought to be due to interplay of genetic, immune, and environmental factors. A month-of-birth effect, with increased risk for those born in autumn/winter months, has been described in autoimmune conditions such as type 1 diabetes and autoimmune thyroid disease. Month-of-birth effect was investigated in 2 independent cohorts of AAD subjects. The monthly distribution of birth in AAD patients was compared with that of the general population using the cosinor test. A total of 415 AAD subjects from the United Kingdom cohort were compared with 8 180 180 United Kingdom births, and 231 AAD subjects from the Polish cohort were compared with 2 421 384 Polish births. Association between month of birth and the susceptibility to AAD. In the entire cohort of AAD subjects, month-of-birth distribution analysis showed significant periodicity with peak of births in December and trough in May (P = .028). Analysis of the odds ratio distribution based on month of birth in 2 cohorts of patients with AAD versus the general population revealed a December peak and May trough, and January peak and July trough, in the United Kingdom and Polish cohorts, respectively. For the first time, we demonstrate that month of birth exerts an effect on the risk of developing AAD, with excess risk in individuals born in winter months and a protective effect when born in the summer. Exposure to seasonal viral infections in the perinatal period, coupled with vitamin D deficiency, could lead to dysregulation of innate immunity affecting the risk of developing AAD.
The origin of polygonal troughs on the northern plains of Mars
NASA Astrophysics Data System (ADS)
Pechmann, J. C.
1980-05-01
The morphology, distribution, geologic environment and relative age of large-scale polygonal trough systems on Mars are examined. The troughs are steep-walled, flat-floored, sinuous depressions typically 200-800 m wide, 20-120 m deep and spaced 5-10 km apart. The mechanics of formation of tension cracks is reviewed to identify the factors controlling the scale of tension crack systems; special emphasis is placed on thermal cracking in permafrost. It is shown that because of the extremely large scale of the Martian fracture systems, they could not have formed by thermal cracking in permafrost, dessication cracking in sediments or contraction cracking in cooling lava. On the basis of photogeologic evidence and analog studies, it is proposed that polygonal troughs on the northern plains of Mars are grabens.
Monson, H.; Hutter, E.
1961-07-11
A seal is described for a cover closing an opening in the top of a pressure vessel that may house a nuclear reactor. The seal comprises a U-shaped trough formed on the pressure vessel around the opening therein, a mass of metal in the trough, and an edge flange on the cover extending loosely into the trough and dipping into the metal mass. The lower portion of the metal mass is kept melted, and the upper portion, solid. The solid pontion of the metal mass prevents pressure surges in the vessel from expelling the liquid portion of the metal mass from the trough; the liquld portion, thus held in place by the solid portion, does not allow gas to go through, and so gas cannot escape through shrinkage holes in the solid portion.
A vacuum tube vee-trough collector for solar heating and air conditioning applications
NASA Technical Reports Server (NTRS)
Selcuk, M. K.
1978-01-01
An analysis is conducted of the performance of a vee-trough vacuum tube collector proposed for use in solar heating and cooling applications. The vee-trough reflector is a triangular sectioned, flat surfaced reflector, whose axis is laid in the East-West direction. A vacuum tube receiver placed at the bottom of the vee-trough collects solar heat most efficiently since convection is completely eliminated. Radiation losses are reduced by use of selective coatings on the absorber. Owing to its high temperature capabilities (300-400 F), the proposed scheme could also be used for power generation applications in combination with an organic Rankine conversion system. It is especially recommended for unattended pumping stations since the reflectors only require reversal once every six months.
Method and apparatus for automatically detecting patterns in digital point-ordered signals
Brudnoy, David M.
1998-01-01
The present invention is a method and system for detecting a physical feature of a test piece by detecting a pattern in a signal representing data from inspection of the test piece. The pattern is detected by automated additive decomposition of a digital point-ordered signal which represents the data. The present invention can properly handle a non-periodic signal. A physical parameter of the test piece is measured. A digital point-ordered signal representative of the measured physical parameter is generated. The digital point-ordered signal is decomposed into a baseline signal, a background noise signal, and a peaks/troughs signal. The peaks/troughs from the peaks/troughs signal are located and peaks/troughs information indicating the physical feature of the test piece is output.
Method and apparatus for automatically detecting patterns in digital point-ordered signals
Brudnoy, D.M.
1998-10-20
The present invention is a method and system for detecting a physical feature of a test piece by detecting a pattern in a signal representing data from inspection of the test piece. The pattern is detected by automated additive decomposition of a digital point-ordered signal which represents the data. The present invention can properly handle a non-periodic signal. A physical parameter of the test piece is measured. A digital point-ordered signal representative of the measured physical parameter is generated. The digital point-ordered signal is decomposed into a baseline signal, a background noise signal, and a peaks/troughs signal. The peaks/troughs from the peaks/troughs signal are located and peaks/troughs information indicating the physical feature of the test piece is output. 14 figs.
Preliminary Report on Cruise NBP01-01, East Antarctic Margin
NASA Astrophysics Data System (ADS)
Leventer, A.; Brachfeld, S.; Domack, E.; Dunbar, R.; Manley, P.; McClennen, C.; Kryc, K.; Beaman, R.; Moy, A.; Pike, J.; Shevenell, A.; Taylor, F.
2001-12-01
Cruise NBP01-01 of the RVIB NB Palmer was a marine geologic and geophysical investigation of the East Antarctic Margin, from Wilkes Land to Edward VIII Gulf, between approximately 150 E to 50 E. The primary objective of the cruise was to develop a record of climate and oceanographic change during the Quaternary, using sediment cores collected via a combination of short and long coring (25 meter jumbo piston cores [JPCs]). Specific goals of this project include development of (1) a century to millennial-scale record of Holocene paleoenvironments and (2) a record of previous stadial and interstadial events on the shelf. Fieldwork on NBP01-01 is a continuation of previous work along the Antarctic Peninsula and in the Ross Sea that has helped us develop an understanding of both the glacial-interglacial history of Antarctica as well as the details of climate variability within the present interglacial. However, both the Antarctic Peninsula and the Ross Sea are influenced primarily by the West Antarctic Ice Sheet, while limited information has been acquired based on data from the East Antarctic Margin. Given large-scale differences between these systems, Cruise NBP0101 gave us the chance to combine our previous knowledge with new data to develop an integrated perspective on climate history in Antarctica through the Quaternary. Core sites were selected based on a combination of sub-bottom profiling via the Bathy2000 and seafloor mapping using the MultiBeam, in addition to information based on previous work. Two depositional environments were targeted - deep basins and troughs of the shelf, and the Prydz Channel and Amery Depression. Deeps investigated include the Mertz Trough, Mertz-Ninnis Trough, and the Dumont d'Urville Trough along the Wilkes Land Margin, the Svenner Channel in Prydz Bay, Nielsen Basin and Iceberg Alley along the Mac.Robertson Shelf, and Edward VIII Gulf, off Enderby Land. A total of 13 JPCs were recovered from these sites, with cores often paired to obtain both the highest resolution record possible and a lower resolution record reaching back to glacial conditions. The four cores opened so far demonstrate complete Holocene records and reach back to glacial sediments. In the Prydz Channel and Amery Depression, three JPCs were collected. Initial data suggest these cores penetrate sequences of up to 5 alternating siliceous mud and glacial units.
Improved 3D seismic images of dynamic deformation in the Nankai Trough off Kumano
NASA Astrophysics Data System (ADS)
Shiraishi, K.; Moore, G. F.; Yamada, Y.; Kinoshita, M.; Sanada, Y.; Kimura, G.
2016-12-01
In order to improve the seismic reflection image of dynamic deformation and seismogenic faults in the Nankai trough, the 2006 Kumano 3D seismic dataset was reprocessed from the original field records by applying advanced technologies a decade after the data acquisition and initial processing. The 3D seismic survey revealed the geometry of megasplay fault system. However, there were still unclear regions in the accretionary prism beneath from Kumano basin to the outer ridge, because of sea floor multiple reflections and noise caused by the Kuroshio current. For the next stage of deep scientific drilling into the Nankai trough seismogenic zone, it is essential to know exactly the shape and depth of the megasplay, and fine structures around the drilling site. Three important improvements were achieved in data processing before imaging. First, full deghosting and optimized zero phasing techniques could recover broadband signals, especially in low frequency, by compensating for ghost effects at both source and receiver, and removing source bubbles. Second, the multiple reflections better attenuated by applying advanced techniques in combination, and the strong noise caused by the Kuroshio were attenuated carefully. Third, data regularization by means of the optimized 4D trace interpolation was effective both to mitigate non-uniform fold distribution and to improve data quality. Further imaging processes led to obvious improvement from previous results by applying PSTM with higher order correction of VTI anisotropy, and PSDM based on the velocity model built by reflection tomography with TTI anisotropy. Final reflection images show new geological aspects, such as clear steep dip faults around the "notch", and fine scale faults related to main thrusts in frontal thrust zone. The improved images will highly contribute to understanding the deformation process in the old accretionary prism and seismogenic features related to the megasplay faults.
Rice, William E
2004-12-01
A sub-surface desert water harvester was constructed in the sagebrush steppe habitat of south-central Idaho, U.S.A. The desert water harvester utilizes a buried micro-catchment and three buried storage tanks to augment water for wildlife during the dry season. In this region, mean annual precipitation (MAP) ranges between about 150-250 mm (6"-10"), 70% of which falls during the cold season, November to May. Mid-summer through early autumn, June through October, is the dry portion of the year. During this period, the sub-surface water harvester provides supplemental water for wildlife for 30-90 days, depending upon the precipitation that year. The desert water harvester is constructed with commonly available, "over the counter" materials. The micro-catchment is made of a square-shaped, 20 mL. "PERMALON" polyethylene pond liner (approximately 22.9 m x 22.9 m = 523 m2) buried at a depth of about 60 cm. A PVC pipe connects the harvester with two storage tanks and a drinking trough. The total capacity of the water harvester is about 4777 L (1262 U.S. gallons) which includes three underground storage tanks, a trough and pipes. The drinking trough is refined with an access ramp for birds and small animals. The technology is simple, cheap, and durable and can be adapted to other uses, e.g. drip irrigation, short-term water for small livestock, poultry farming etc. The desert water harvester can be used to concentrate and collect water from precipitation and run-off in semi-arid and arid regions. Water harvested in such a relatively small area will not impact the ground water table but it should help to grow small areas of crops or vegetables to aid villagers in self-sufficiency.
Empirical Model of the Location of the Main Ionospheric Trough
NASA Astrophysics Data System (ADS)
Deminov, M. G.; Shubin, V. N.
2018-05-01
The empirical model of the location of the main ionospheric trough (MIT) is developed based on an analysis of data from CHAMP satellite measured at the altitudes of 350-450 km during 2000-2007; the model is presented in the form of the analytical dependence of the invariant latitude of the trough minimum Φm on the magnetic local time (MLT), the geomagnetic activity, and the geographical longitude for the Northern and Southern Hemispheres. The time-weighted average index Kp(τ), the coefficient of which τ = 0.6 is determined by the requirement of the model minimum deviation from experimental data, is used as an indicator of geomagnetic activity. The model has no limitations, either in local time or geomagnetic activity. However, the initial set of MIT minima mainly contains data dealing with an interval of 16-08 MLT for Kp(τ) < 6; therefore, the model is rather qualitative outside this interval. It is also established that (a) the use of solar local time (SLT) instead of MLT increases the model error no more than by 5-10%; (b) the amplitude of the longitudinal effect at the latitude of MIT minimum in geomagnetic (invariant) coordinates is ten times lower than that in geographical coordinates.
Strain Accumulation Estimated from Seafloor Crustal Deformation at the Nankai Trough, Japan
NASA Astrophysics Data System (ADS)
Tadokoro, K.; Watanabe, T.; Nagai, S.; Ikuta, R.; Okuda, T.; Kenji, Y.; Sakata, T.
2012-12-01
Our research has developed an observation system for seafloor crustal deformation composed of the kinematic GPS and acoustic ranging techniques [Tadokoro et al., 2006; Ikuta et al., 2008]. We monitored crustal deformation at the Nankai Trough, Japan, where the Philippine Sea Plate subducts beneath the Amurian Plate. The convergence rate is predicted at 60 mm/y in the N59W direction by the Euler vector of REVEL [Sella et al., 2002]. We installed three monitoring sites (named KMN, KMS, and KME) on the seafloor at depths of about 1920-2030 m. The sites KMN and KMS are installed perpendicular to the trough axis with a spacing of 20 km; the site KME is 50 km from KMN and KMS in the direction parallel to the trough axis. The monitoring was started in 2004, 2005, and 2008 at KMS, KMN, and KME, respectively. The numbers of measurements are 16, 20, and 5 times at KMN, KMS, and KME, respectively. We obtained 3-7 years averaged horizontal site velocities within ITRF2000 adopting a robust estimation method with Tukey's biweight function to the time series of site position measured until the end of 2011. Substituting the synthetic rigid block motions of the Amurian Plate from the velocities within ITRF2000, we obtained the following site velocities with respect to the Amurian Plate [Tadokoro et al., 2012]: KMN 41±4 mm/y, N77±7W KMS 43±5 mm/y, N80±6W KME 42±5 mm/y, N80±7W In contrast, the on-land GPS horizontal velocities along the coast is 23-33 mm/y toward N74-80W. The present observational results show: (1) the velocity vectors are all the same length and direction, which indicates no internal deformation in this region; (2) the back-slip model predicts that the plate interface beneath the region is uniformly locked with coupling ratios of 60-80 %, indicating strain accumulation that will be released during the anticipated mega-thrust Tonankai earthquake; and (3) the directions of site velocities differ from that of convergence vector by 20 degrees, which is affected by the oblique subduction of the Philippine Sea Plate. We started monitoring of seafloor crustal deformation at a new site, KMC, in this year. This site is located between KMN and KMS. The monitoring at KMC enable us to depict dense (with a span of 10 km) crustal deformation profile that is related to strain accumulation, in the direction perpendicular to the trough axis. We plan to measure the position at KMC twice by the end of this year. We also continue to measure the position at KMS and KME. The number of measurements at KME is extremely few compared to the other sites in particular, and it is important to continue the measurement for obtaining stable site velocity. We report the results of monitoring preformed in this year. Acknowledgments: We are grateful to the captain and crews of R/V "Asama" of Mie Prefecture Fisheries Research Institute, Japan. This study has been partly promoted by Ministry of Education, Culture, Sports, Science and Technology, Japanese Government.
Xu, Y; Li, Y F; Zhang, D; Dockendorf, M; Tetteh, E; Rizk, M L; Grobler, J A; Lai, M-T; Gobburu, J; Ankrom, W
2016-08-01
We applied model-based meta-analysis of viral suppression as a function of drug exposure and in vitro potency for short-term monotherapy in human immunodeficiency virus type 1 (HIV-1)-infected treatment-naïve patients to set pharmacokinetic targets for development of nonnucleoside reverse transcriptase inhibitors (NNRTIs) and integrase strand transfer inhibitors (InSTIs). We developed class-specific models relating viral load kinetics from monotherapy studies to potency normalized steady-state trough plasma concentrations. These models were integrated with a literature assessment of doses which demonstrated to have long-term efficacy in combination therapy, in order to set steady-state trough concentration targets of 6.17- and 2.15-fold above potency for NNRTIs and InSTIs, respectively. Both the models developed and the pharmacokinetic targets derived can be used to guide compound selection during preclinical development and to predict the dose-response of new antiretrovirals to inform early clinical trial design. © 2016 The Authors. Clinical and Translational Science published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.
2003-01-15
At first glance, this NASA Mars Odyssey image showing impact craters and linear ridges and troughs is typical of the southern highlands. However, upon closer examination migrating sand dunes are observed within the troughs.
Morton, J.L.; Holmes, M.L.; Koski, R.A.
1987-01-01
Seismic-reflection profiles over the sediment-filled Escanaba Trough at the southern Gorda Ridge reveal a series of volcanic centers that pierce the sediment. The volcanic edifices are 3 to 6 km in diameter and are spaced at 15 to 20 km intervals along the axis of the trough. Composition and form of sulfide samples obtained from the bank suggest significant interaction between hydrothermal fluids and sediment at depth, and deposition of sulfide within the sediment pile.-from Authors
Crustal architecture of the eastern margin of Japan Sea: back-arc basin opening and contraction
NASA Astrophysics Data System (ADS)
No, T.; Sato, T.; Takahashi, N.; Kodaira, S.; Kaneda, Y.; Ishiyama, T.; Sato, H.
2012-12-01
Although large earthquakes such as the 1964 Niigata earthquake (M 7.5), 1983 Nihonkai-Chubu earthquake (M 7.8), and 1993 Hokkaido Nansei-Oki earthquake (M 7.8) have caused large amounts of damage to the eastern margin of the Japan Sea, a substantial number of seismic studies have been conducted for the seismogenic zone on the Pacific Ocean side of Japan. In addition, the detail of the source fault model for the eastern margin of the Japan Sea is not well defined for all cases. This highlights the need for further studies to investigate seismic imaging. Therefore, we have collaborated with other Japanese research institutions for a project titled "Priority Investigations of Strain Concentration Areas" (which is funded by Special Coordination Funds for Promoting Science and Technology, Japan). This project has conducted seismic surveys from 2009 to 2012 using the deep-sea research vessel, Kairei, from the Japan Agency for Marine-Earth Science and Technology. There is a strain concentration area in the eastern part of the survey area (Okamura et al., 1995). The western part of the survey area includes the Yamato Basin and Japan Basin. It is very important to study the crustal structure in the seismotectonic studies of the eastern margin of the Japan Sea. We conducted a marine seismic survey by using a multichannel seismic (MCS) system and ocean bottom seismographs (OBSs) along the eastern margin of the Japan Sea. Seismic data were acquired along 42 lines with a total length of approximately 9,000 km. The following results were obtained from seismic imaging. On the basis of the results of the MCS imaging, active reverse faults and folds were observed in the margin of the Toyama Trough; however, the sedimentary layers in the trough were flat. In the sedimentary layers and crusts of the Sado Ridge, Mogami Trough, and source area of the 1964 Niigata earthquake located north of the Sado Island, greater deformation was observed. The deformation weakened toward the Yamato Basin and Japan Basin; however, the development of an asymmetric anticline and its associated reverse fault was observed off Akita prefecture, which could indicate a very recent growth structure. This development is associated with an active structure on the southern extension of the fault that caused the 1983 Nihonkai-Chubu Earthquake. On the other hand, the results from the seismic refraction/wide-angle reflection imaging using OBSs indicated that the area from the basin to the continental shelf, including the source area of the 1964 Niigata Earthquake, and the island arc crust had a large lateral variation in the upper and middle crust. In contrast, beneath the source area of the 1983 Nihonkai-Chubu Earthquake, the crustal structure is interpreted as a transitional crust between oceanic and island arc crusts, with larger variation in the P-wave velocity than those of the surrounding areas. Furthermore, the crust of the Yamato Basin area is thicker than a typical oceanic crust, whereas the crust of the Japan Basin area is similar to a typical oceanic crust.
Stable interior, showing center aisle, stalls, and feed troughs. View ...
Stable interior, showing center aisle, stalls, and feed troughs. View looking southwest - Fort Hill Farm, Stable, West of Staunton (Roanoke) River between Turkey & Caesar's Runs, Clover, Halifax County, VA
Supersonic burning in separated flow regions
NASA Technical Reports Server (NTRS)
Zumwalt, G. W.
1982-01-01
The trough vortex phenomena is used for combustion of hydrogen in a supersonic air stream. This was done in small sizes suitable for igniters in supersonic combustion ramjets so long as the boundary layer displacement thickness is less than 25% of the trough step height. A simple electric spark, properly positioned, ignites the hydrogen in the trough corner. The resulting flame is self sustaining and reignitable. Hydrogen can be injected at the base wall or immediately upstream of the trough. The hydrogen is introduced at low velocity to permit it to be drawn into the corner vortex system and thus experience a long residence time in the combustion region. The igniters can be placed on a skewed back step for angles at least up to 30 deg. without affecting the igniter performance significantly. Certain metals (platinum, copper) act catalytically to improve ignition.
NASA Astrophysics Data System (ADS)
Tu, Yoko; Heki, Kosuke
2017-09-01
We studied 38 slow slip events (SSEs) in 1997-2016 beneath the Iriomote Island, southwestern Ryukyu Arc, Japan, using continuous Global Navigation Satellite Systems data. These SSEs occur biannually on the same fault patch at a depth of 30 km on the subducting Philippine Sea Plate slab with average moment magnitudes (
Surface expression of the Chicxulub crater
Pope, K O; Ocampo, A C; Kinsland, G L; Smith, R
1996-06-01
Analyses of geomorphic, soil, and topographic data from the northern Yucatan Peninsula, Mexico, confirm that the buried Chicxulub impact crater has a distinct surface expression and that carbonate sedimentation throughout the Cenozoic has been influenced by the crater. Late Tertiary sedimentation was mostly restricted to the region within the buried crater, and a semicircular moat existed until at least Pliocene time. The topographic expression of the crater is a series of features concentric with the crater. The most prominent is an approximately 83-km-radius trough or moat containing sinkholes (the Cenote ring). Early Tertiary surfaces rise abruptly outside the moat and form a stepped topography with an outer trough and ridge crest at radii of approximately 103 and approximately 129 km, respectively. Two discontinuous troughs lie within the moat at radii of approximately 41 and approximately 62 km. The low ridge between the inner troughs corresponds to the buried peak ring. The moat corresponds to the outer edge of the crater floor demarcated by a major ring fault. The outer trough and the approximately 62-km-radius inner trough also mark buried ring faults. The ridge crest corresponds to the topographic rim of the crater as modified by postimpact processes. These interpretations support previous findings that the principal impact basin has a diameter of approximately 180 km, but concentric, low-relief slumping extends well beyond this diameter and the eroded crater rim may extend to a diameter of approximately 260 km.
NASA Astrophysics Data System (ADS)
Wang, Long; Yu, Min; Liu, Yan; Liu, Jiwen; Wu, Yonghua; Li, Li; Liu, Jihua; Wang, Min; Zhang, Xiao-Hua
2018-04-01
As an ideal place to study back-arc basins and hydrothermal eco-system, Okinawa Trough has attracted the interests of scientists for decades. However, there are still no in-depth studies targeting the bacterial community of the seafloor sediments and hydrothermal deposits in Okinawa Trough. In the present study, we reported the bacterial community of the surface deposits of a newly found hydrothermal field in the southern Okinawa Trough, and the horizontal and vertical variation of bacterial communities in the sediments of the northern Okinawa Trough. The hydrothermal deposits had a relatively high 16S rRNA gene abundance but low bacterial richness and diversity. Epsilonproteobacteria and Bacteroidetes were predominant in hydrothermal deposits whereas Deltaproteobacteria, Gammaproteobacteria and Chloroflexi were abundant across all samples. The bacterial distribution in the seafloor of Okinawa Trough was significantly correlated to the content of total nitrogen, and had consistent relationship with total carbon. Gradual changes of sulfur-oxidizing bacteria were found with the distance away from hydrothermal fields, while the hydrothermal activity did not influence the distribution of the major clades of sulfate-reducing bacteria. Higher abundance of the sulfur cycle related genes (aprA and dsrB), and lower abundance of the bacterial ammonia-oxidizing related gene (amoA) were quantified in hydrothermal deposits. In addition, the present study also compared the inter-field variation of Epsilonproteobacteria among multi-types of hydrothermal vents, revealing that the proportion and diversity of this clade were quite various.
NASA Astrophysics Data System (ADS)
Klages, J. P.; Hillenbrand, C. D.; Kuhn, G.; Smith, J. A.; Graham, A. G. C.; Nitsche, F. O.; Frederichs, T.; Arndt, J. E.; Gebhardt, C.; Robin, Z.; Uenzelmann-Neben, G.; Gohl, K.; Jernas, P.; Wacker, L.
2017-12-01
In recent years several previously undiscovered grounding-zone wedges (GZWs) have been described within the Abbot-Cosgrove palaeo-ice stream trough on the easternmost Amundsen Sea Embayment shelf. These GZWs document both the Last Glacial Maximum (LGM; 26.5-19 cal. ka BP) grounding-line extent and the subsequent episodic retreat within this trough that neighbors the larger Pine Island-Thwaites trough to the west. Here we combine bathymetric, seismic, and geologic data showing that 1) the grounding line in Abbot Trough did not reach the continental shelf break at any time during the last glacial period, and 2) a prominent stacked GZW constructed from six individual wedges lying upon another was deposited 100 km upstream from the LGM grounding-line position. The available data allow for calculating volumes for most of these individual GZWs and for the entire stack. Sediment cores were recovered seawards from the outermost GZW in the trough, and from the individual wedges of the stacked GZW in order to define the LGM grounding-line extent, and provide minimum grounding-line retreat ages for the respective positions on the stacked GZW. We present implications of a grounded-ice free outer shelf throughout the last glacial period. Furthermore, we assess the significance of the grounding-line stillstand period recorded by the stacked GZW in Abbot Trough for the timing of post-LGM retreat of the West Antarctic Ice Sheet from the Amundsen Sea Embayment shelf.
Carbonate mound development in contrasting settings on the Irish margin
NASA Astrophysics Data System (ADS)
van der Land, Cees; Eisele, Markus; Mienis, Furu; de Haas, Henk; Hebbeln, Dierk; Reijmer, John J. G.; van Weering, Tjeerd C. E.
2014-01-01
Cold-water coral carbonate mounds, formed by framework building cold-water corals, are found in several mound provinces on the Irish margin. Differences in cold-water coral mound development rates and sediment composition between mounds at the southwest Rockall Trough margin and the Galway Mound in the Porcupine Seabight are investigated. Variations in sediment composition in the two mound provinces are related to the local environmental conditions and sediment sources. Mound accumulation rates are possibly higher at the Galway Mound probably due to a higher influx of hemipelagic fine grained non-carbonate sediments. In both cold-water coral mound areas, mound growth has been continuous for the last ca 11,000 years, before this period several hiatuses and unconformities exist in the mound record. The most recent unconformity can be correlated across multiple mounds and mound provinces at the Irish margin on the basis of apparent age. On the southwest Rockall Trough margin these hiatuses/unconformities are associated with post-depositional aragonite dissolution in, and lithification of, certain intervals, while at Galway Mound no lithification occurs. This study revealed that the influx and types of material transported to cold-water coral mounds may have a direct impact on the carbonate mound accumulation rate and on post-depositional processes. Significantly, the Logachev Mounds on the SW Rockall Trough margin accumulate slower but, because they contain lithified layers, are less susceptible to erosion. This net effect may account for their larger size compared to the Belgica Mounds.
Environmental risks of the gas hydrate field development in the Eastern Nankai Trough
NASA Astrophysics Data System (ADS)
Yamamoto, K.; Nagakubo, S.
2009-12-01
To establish any kinds of new energy resources, environmental impacts of the technology should be well understood before full industrial implementation. Methane hydrate (MH), a relatively clean fossil energy with low CO2 and no SOx emission, is not an exception. Because methane gas itself has strong greenhouse gas effect, and methane hydrate is not stable under the atmospheric pressure and room temperature, public image of MH field development is very risky game and potentially disastrous to the global climate. However, the real physics of the MH bearing sediments is far different from such images. MH21 Research Consortium in Japan has studied about the resource assessment and production techniques to develop MH since 2001. As the results, we found several gas hydrate concentrated zones with pore filling type hydrate in sandy layers of turbidite sediment in the Eastern Nankai Trough area off coasts of the Central Japan. The depressurization technique, in the other word, in-situ MH dissociation by water production and natural heat supply from surrounding formation, will be used as the basic method to produce methane gas from MH. Under the conditions, we have evaluated realistic environmental risk of the MH production. Because the most MH found in the Eastern Nankai Trough are composed of biogenic and almost pure methane, there is no concern of sea water contamination by oil releases that is the most common environmental disaster caused by misconducts of the oil industry. Also MH reservoirs there are not pressurized, and blowout of wells during drilling is very unlikely. Endothermic MH dissociation process decreases formation temperature with depressurization, and give negative feedback, then, there is no chance of chain reaction. Heat supply from surrounding formations is necessary for continuous dissociation, but heat transfer in the formations is relatively slow, and the dissociation rate is limited. Once the operation to pump water in boreholes for depressurization is stopped, or some troubles break surface facilities, pressure recovers to the original condition, but formation temperature is kept low by inflow of cold sea water. Therefore, the gas release risk of the offshore MH field is lower than conventional oil and gas. There can be a slight chance to release gas to seafloor after the production along with pressure recovery though natural and man-made pathways such as poorly abandoned wells, reactivated fractures or faults, etc. Even in the case, most of the discharged gas will be dissolved in to seawater, and almost no chance to discharge it into atmosphere. Another possible scenario is surface instability caused by weakened formation due to MH dissociation. To mitigate the risk to avoid catastrophic phenomena, site selection is the key. During the offshore production tests planned in 2012 and 2014, MH21 will conduct modelling, monitoring and verification program to quantify the real environmental risks of the MH field development.
Landslides in Valles Marineris, Mars
NASA Technical Reports Server (NTRS)
Lucchitta, B. K.
1979-01-01
The morphology of the landslides in the Martian equatorial troughs, the geologic structure of the troughs, the time of emplacement, the similarity to terrestrial landslides, and the origin and mechanism of transport are analyzed. About 35 large landslides well-resolved on Viking images were examined, and it is found that the major landslides cover 31,000 sq km of the trough floors, and individual slides range in area from 40 to 7000 sq km. The morphologic variations of the landslides can be attributed mainly to their degree of confinement on trough floors. Many prominent landslides appear to be of similar age and were emplaced after a major faulting that dropped the trough floors. Most sliding occurred after the created scarps were dissected into spurs, gullies, and tributary canyons. Emplacement of the landslides approximately coincided with a late episode of major eruptive activity of the Tharsis volcanoes, and it is suggested that the slides may have originated as gigantic mudflows with slump blocks at their heads. The large size of many landslides is due to the fault scarps as high as 7 km on which they formed in the absence of vigorous fluvial erosion. The landslides suggest that Mars is earthlike in some respects, which may be important for further evaluations.
Morphology-dependent water budgets and nutrient fluxes in arctic thaw ponds
Koch, Joshua C.; Gurney, Kirsty; Wipfli, Mark S.
2014-01-01
Thaw ponds on the Arctic Coastal Plain of Alaska are productive ecosystems, providing habitat and food resources for many fish and bird species. Permafrost in this region creates unique pond morphologies: deep troughs, shallow low-centred polygons (LCPs) and larger coalescent ponds. By monitoring seasonal trends in pond volume and chemistry, we evaluated whether pond morphology and size affect water temperature and desiccation, and nitrogen (N) and phosphorus (P) fluxes. Evaporation was the largest early-summer water flux in all pond types. LCPs dried quickly and displayed high early-summer nutrient concentrations and losses. Troughs consistently received solute-rich subsurface inflows, which accounted for 12 to 42 per cent of their volume and may explain higher P in the troughs. N to P ratios increased and ammonium concentrations decreased with pond volume, suggesting that P and inorganic N availability may limit ecosystem productivity in older, larger ponds. Arctic summer temperatures will likely increase in the future, which may accelerate mid-summer desiccation. Given their morphology, troughs may remain wet, become warmer and derive greater nutrient loads from their thawing banks. Overall, seasonal- to decadal-scale warming may increase ecosystem productivity in troughs relative to other Arctic Coastal Plain ponds.
NASA Astrophysics Data System (ADS)
Lockwood, M.
1981-06-01
Observations of the amplitudes and Doppler shifts of received HF radio waves are compared with model predictions made using a two-dimensional ray-tracing program. The signals are propagated over a sub-auroral path, which is shown to lie along the latitudes of the mid-latitude trough at times of low geomagnetic activity. Generalizing the predictions to include a simple model of the trough in the density and height of the F2 peak enables the explanation of the anomalous observed diurnal variations. The behavior of received amplitude, Doppler shift, and signal-to-noise ratio as a function of the K sub p index value, the time of day, and the season (in 17 months of continuous recording) is found to agree closely with that predicted using the statistical position of the trough as deduced from 8 years of Alouette satellite soundings. The variation in the times of the observation of large signal amplitudes with the K sub p value and the complete absence of such amplitudes when it exceeds 2.75 are two features that implicate the trough in these effects.
Martian Polar Caps: Folding, Faulting, Flowing Glaciers of Multiple Interbedded Ices
NASA Astrophysics Data System (ADS)
Kargel, J. S.
2001-12-01
The Martian south polar cap (permanent CO2 cap and polar layered deposits), exhibit abundant, varied, and widespread deformational phenomena. Folding and boudinage are very common. Strike-slip or normal faults are rarer. Common in the vicinity of major troughs and scarps are signs of convergent flow tectonics manifested as wrinkle-ridge-like surface folds, thrust faults, and viscous forebulges with thin-skinned extensional crevasses and wrinkle-ridge folds. Such flow convergence is predicted by theory. Boudinage and folding at the 300-m wavelength scale, indicating rheologically contrasting materials, is widely exposed at deep levels along erosional scarps. Independent morphologic evidence indicates south polar materials of contrasting volatility. Hence, the south polar cap appears to be a multiphase structure of interbedded ices. The north polar cap locally also exhibits flow indicators, though they are neither as common nor as varied as in the south. The large-scale quasi-spiral structure of the polar caps could be a manifestation of large-scale boudinage. According to this scenario, deep-level boudinage continuously originates under the glacial divide (the polar cap summit). Rod-like boudin structures are oriented transverse to flow and migrate outward with the large-scale flow field. Troughs develop over areas between major boudins. A dynamic competition, and possibly a rough balance, develops between the local flow field in the vicinity of a trough (which tends to close the trough by lateral closure and upwelling flow) and sublimation erosion (which tends to widen and deepen them). Over time, the troughs flow to the margins of the polar cap where they, along with other polar structures, are destroyed by sublimation. Major ice types contributing to rheological and volatility layering may include, in order of highest to lowest mechanical strength, CO2 clathrate hydrate, water ice containing inert/insoluble dust, pure water ice, water ice containing traces of liquid-soluble salts, water ice containing traces of solid-soluble acids, CO2 ice. This is also nearly the same sequence of highest to lowest melting/dissociation points, but it is different than the sequence of volatility. This geologic-structural interpretation and specific chemical models are amenable to testing by computational means and point the way toward future needed observations, including complete high-resolution imaging of the polar caps, measurement of flow fields (possibly by laser interferometry), mapping of subsurface structures (by radar and/or seismic methods), and determination of composition (by penetrators, drillers, or borers). New lab data are needed on the physical properties of candidate ices.
Gibson, Ashley; Kaplan, Sheldon L; Vallejo, Jesus G
2018-04-26
Coagulase-negative staphylococci (CoNS) are a common cause of pediatric ventricular shunt infections. The Infectious Diseases Society of America recommends vancomycin serum troughs of 15-20 µg/mL when treating CoNS shunt infections in adult patients. We report a series of pediatric cases of CoNS shunt infections in which clinical cure was obtained with troughs < 15 µg/mL. These findings question the relevance of this recommendation in pediatric patients. © 2018 S. Karger AG, Basel.
Therapeutic drug monitoring of eculizumab: Rationale for an individualized dosing schedule.
Gatault, Philippe; Brachet, Guillaume; Ternant, David; Degenne, Danielle; Récipon, Guillaume; Barbet, Christelle; Gyan, Emmanuel; Gouilleux-Gruart, Valérie; Bordes, Cécile; Farrell, Alexandra; Halimi, Jean Michel; Watier, Hervé
2015-01-01
The annual cost of eculizumab maintenance therapy in paroxysmal nocturnal hemoglobinuria (PNH) and atypical hemolytic-uremic syndrome (aHUS) exceeds $300,000 per patient. A better understanding of eculizumab pharmacokinetics and subsequent individual dose adjustment could reduce this cost. We measured the trough eculizumab concentration in 9 patients with maintenance therapy (aHUS, n = 7; PNH, n = 2) and determined: 1) the intra- and inter-individual variability; 2) the influence of weight on eculizumab pharmacokinetics; and 3) the rate of elimination of eculizumab following discontinuation. A one-compartment model was developed to describe the pharmacokinetics of eculizumab and predicted complement activity by body weight. Trough eculizumab concentrations were >50 µg/mL in 9/9, >100 µg/mL in 8/9, and >300 µg/mL in 5/9 of patients. Intra-individual variability was low but eculizumab concentrations, closely correlated with patient weight (R(2) = 0.66, p = 0.034), varied broadly (55 ± 12 to 733 ± 164 µg/mL). Pharmacokinetic modeling showed that the elimination half-life varied greatly, with an increase from 7.8 d in a patient weighing 100 kg to 19.5 d in a 40 kg patient. We predicted that infusions of 1200 mg could be spaced every 4 or 6 weeks in patients weighing <90 and <70 kg, respectively. In this pilot study, the current recommended use of a fixed eculizumab dose for maintenance therapy is associated with excessively high trough concentrations in many patients. Further prospective larger studies are now required to support an individualized schedule adjusted for patient weight and based on the observed trough serum eculizumab concentration.
Therapeutic drug monitoring of eculizumab: Rationale for an individualized dosing schedule
Gatault, Philippe; Brachet, Guillaume; Ternant, David; Degenne, Danielle; Récipon, Guillaume; Barbet, Christelle; Gyan, Emmanuel; Gouilleux-Gruart, Valérie; Bordes, Cécile; Farrell, Alexandra; Halimi, Jean Michel; Watier, Hervé
2015-01-01
The annual cost of eculizumab maintenance therapy in paroxysmal nocturnal hemoglobinuria (PNH) and atypical hemolytic–uremic syndrome (aHUS) exceeds $300,000 per patient. A better understanding of eculizumab pharmacokinetics and subsequent individual dose adjustment could reduce this cost. We measured the trough eculizumab concentration in 9 patients with maintenance therapy (aHUS, n = 7; PNH, n = 2) and determined: 1) the intra- and inter-individual variability; 2) the influence of weight on eculizumab pharmacokinetics; and 3) the rate of elimination of eculizumab following discontinuation. A one-compartment model was developed to describe the pharmacokinetics of eculizumab and predicted complement activity by body weight. Trough eculizumab concentrations were >50 µg/mL in 9/9, >100 µg/mL in 8/9, and >300 µg/mL in 5/9 of patients. Intra-individual variability was low but eculizumab concentrations, closely correlated with patient weight (R2 = 0.66, p = 0.034), varied broadly (55 ± 12 to 733 ± 164 µg/mL). Pharmacokinetic modeling showed that the elimination half-life varied greatly, with an increase from 7.8 d in a patient weighing 100 kg to 19.5 d in a 40 kg patient. We predicted that infusions of 1200 mg could be spaced every 4 or 6 weeks in patients weighing <90 and <70 kg, respectively. In this pilot study, the current recommended use of a fixed eculizumab dose for maintenance therapy is associated with excessively high trough concentrations in many patients. Further prospective larger studies are now required to support an individualized schedule adjusted for patient weight and based on the observed trough serum eculizumab concentration. PMID:26337866
Multi-Scale Peak and Trough Detection Optimised for Periodic and Quasi-Periodic Neuroscience Data.
Bishop, Steven M; Ercole, Ari
2018-01-01
The reliable detection of peaks and troughs in physiological signals is essential to many investigative techniques in medicine and computational biology. Analysis of the intracranial pressure (ICP) waveform is a particular challenge due to multi-scale features, a changing morphology over time and signal-to-noise limitations. Here we present an efficient peak and trough detection algorithm that extends the scalogram approach of Scholkmann et al., and results in greatly improved algorithm runtime performance. Our improved algorithm (modified Scholkmann) was developed and analysed in MATLAB R2015b. Synthesised waveforms (periodic, quasi-periodic and chirp sinusoids) were degraded with white Gaussian noise to achieve signal-to-noise ratios down to 5 dB and were used to compare the performance of the original Scholkmann and modified Scholkmann algorithms. The modified Scholkmann algorithm has false-positive (0%) and false-negative (0%) detection rates identical to the original Scholkmann when applied to our test suite. Actual compute time for a 200-run Monte Carlo simulation over a multicomponent noisy test signal was 40.96 ± 0.020 s (mean ± 95%CI) for the original Scholkmann and 1.81 ± 0.003 s (mean ± 95%CI) for the modified Scholkmann, demonstrating the expected improvement in runtime complexity from [Formula: see text] to [Formula: see text]. The accurate interpretation of waveform data to identify peaks and troughs is crucial in signal parameterisation, feature extraction and waveform identification tasks. Modification of a standard scalogram technique has produced a robust algorithm with linear computational complexity that is particularly suited to the challenges presented by large, noisy physiological datasets. The algorithm is optimised through a single parameter and can identify sub-waveform features with minimal additional overhead, and is easily adapted to run in real time on commodity hardware.
Belal, Tarek S; Daabees, Hoda G; Abdel-Khalek, Magdi M; Mahrous, Mohamed S; Khamis, Mona M
2013-04-01
A new simple spectrophotometric method was developed for the determination of binary mixtures without prior separation. The method is based on the generation of ratio spectra of compound X by using a standard spectrum of compound Y as a divisor. The peak to trough amplitudes between two selected wavelengths in the ratio spectra are proportional to concentration of X without interference from Y . The method was demonstrated by determination of two drug combinations. The first consists of the two antihyperlipidemics: atorvastatin calcium (ATV) and ezetimibe (EZE), and the second comprises the antihypertensives: candesartan cilexetil (CAN) and hydrochlorothiazide (HCT). For mixture 1, ATV was determined using 10 μg/mL EZE as the divisor to generate the ratio spectra, and the peak to trough amplitudes between 231 and 276 nm were plotted against ATV concentration. Similarly, by using 10 μg/mL ATV as divisor, the peak to trough amplitudes between 231 and 276 nm were found proportional to EZE concentration. Calibration curves were linear in the range 2.5-40 μg/mL for both drugs. For mixture 2, divisor concentration was 7.5 μg/mL for both drugs. CAN was determined using its peak to trough amplitudes at 251 and 277 nm, while HCT was estimated using the amplitudes between 251 and 276 nm. The measured amplitudes were linearly correlated to concentration in the ranges 2.5-50 and 1-30 μg/mL for CAN and HCT, respectively. The proposed spectrophotometric method was validated and successfully applied for the assay of both drug combinations in several laboratory-prepared mixtures and commercial tablets.
Belal, Tarek S.; Daabees, Hoda G.; Abdel-Khalek, Magdi M.; Mahrous, Mohamed S.; Khamis, Mona M.
2012-01-01
A new simple spectrophotometric method was developed for the determination of binary mixtures without prior separation. The method is based on the generation of ratio spectra of compound X by using a standard spectrum of compound Y as a divisor. The peak to trough amplitudes between two selected wavelengths in the ratio spectra are proportional to concentration of X without interference from Y. The method was demonstrated by determination of two drug combinations. The first consists of the two antihyperlipidemics: atorvastatin calcium (ATV) and ezetimibe (EZE), and the second comprises the antihypertensives: candesartan cilexetil (CAN) and hydrochlorothiazide (HCT). For mixture 1, ATV was determined using 10 μg/mL EZE as the divisor to generate the ratio spectra, and the peak to trough amplitudes between 231 and 276 nm were plotted against ATV concentration. Similarly, by using 10 μg/mL ATV as divisor, the peak to trough amplitudes between 231 and 276 nm were found proportional to EZE concentration. Calibration curves were linear in the range 2.5–40 μg/mL for both drugs. For mixture 2, divisor concentration was 7.5 μg/mL for both drugs. CAN was determined using its peak to trough amplitudes at 251 and 277 nm, while HCT was estimated using the amplitudes between 251 and 276 nm. The measured amplitudes were linearly correlated to concentration in the ranges 2.5–50 and 1–30 μg/mL for CAN and HCT, respectively. The proposed spectrophotometric method was validated and successfully applied for the assay of both drug combinations in several laboratory-prepared mixtures and commercial tablets. PMID:29403805
NASA Astrophysics Data System (ADS)
Sarki Yandoka, Babangida M.; Abubakar, M. B.; Abdullah, Wan Hasiah; Amir Hassan, M. H.; Adamu, Bappah U.; Jitong, John S.; Aliyu, Abdulkarim H.; Adegoke, Adebanji Kayode
2014-08-01
The Benue Trough of Nigeria is a major rift basin formed from the tension generated by the separation of African and South American plates in the Early Cretaceous. It is geographically sub-divided into Southern, Central and Northern Benue portions. The Northern Benue Trough comprises two sub-basins; the N-S trending Gongola Sub-basin and the E-W trending Yola Sub-basin. The Bima Formation is the oldest lithogenetic unit occupying the base of the Cretaceous successions in the Northern Benue Trough. It is differentiated into three members; the Lower Bima (B1), the Middle Bima (B2) and the Upper Bima (B3). Facies and their stratigraphical distribution analyses were conducted on the Lower Bima Member exposed mainly at the core of the NE-SW axially trending Lamurde Anticline in the Yola Sub-basin, with an objective to interpret the paleodepositional environments, and to reconstruct the depositional model and the stratigraphical architecture. Ten (10) lithofacies were identified on the basis of lithology, grain size, sedimentary structures and paleocurrent analysis. The facies constitute three (3) major facies associations; the gravelly dominated, the sandy dominated and the fine grain dominated. These facies and facies associations were interpreted and three facies successions were recognized; the alluvial-proximal braided river, the braided river and the lacustrine-marginal lacustrine. The stratigraphic architecture indicates a rifted (?pull-apart) origin as the facies distribution shows a progradational succession from a shallow lacustrine/marginal lacustrine (at the axial part of the basin) to alluvial fan (sediment gravity flow)-proximal braided river (gravel bed braided river) and braided river (channel and overbank) depositional systems. The facies stacking patterns depict sedimentation mainly controlled by allogenic factors of climate and tectonism.
On-Field Demonstration Results of Medium Concentration System HSun®
NASA Astrophysics Data System (ADS)
Mendes-Lopes, J.; Pina, L.; Reis, F.; Coelho, S.; Wemans, J.; Sorasio, G.; Pereira, N.
2011-12-01
The paper presents the HSUN®, a new medium concentration photovoltaic (CPV) system, developed and produced by WS Energia S.A. The low cost manufacturing and standard components used by HSUN® technology increases the potential of the system to reach grid parity. The system was designed to have stable performance and low cost manufacturing, with a total active collector area of 1.68 m2 and 6.3 kg/m2 of weight. Based on a 20X integrated parabolic trough with coupled reflective secondary optics, the system uses high efficiency silicon cells, a passive cooling integrated system and is integrated in 1-axis horizontal tracking structure, the WS CPV HORIZON®. The open-chain configuration ensures that the wind drag is greatly reduced, increasing the reliability of the tracker, while the optimized optics design enables a high acceptance angle and uniform distribution of radiation throughout the PV receiver, using low-cost and low-weight components. Ray tracing simulations and experimental imaging acquisitions of the radiation profile were performed and compared, finite element models were used to perform thermal and structural analysis, and a specifically developed model was used to predict the electrical parameters of the receiver as a function of the concentration. All the components that integrate HSUN® technology are produced with machines used in mature industrial sectors thus guarantying mass production and benefiting from economies of scale. The on-field results are presented and discussed.
NASA Astrophysics Data System (ADS)
van Wijk, Esmee M.; Rintoul, Stephen R.; Ronai, Belinda M.; Williams, Guy D.
2010-05-01
The fine-scale circulation around the Heard and McDonald Islands and through the Fawn Trough, Kerguelen Plateau, is described using data from three high-resolution CTD sections, Argo floats and satellite maps of chlorophyll a, sea surface temperature (SST) and absolute sea surface height (SSH). We confirm that the Polar Front (PF) is split into two branches over the Kerguelen Plateau, with the NPF crossing the north-eastern limits of our survey carrying 25 Sv to the southeast. The SPF was associated with a strong eastward-flowing jet carrying 12 Sv of baroclinic transport through the deepest part of Fawn Trough (relative to the bottom). As the section was terminated midway through the trough this estimate is very likely to be a lower bound for the total transport. We demonstrate that the SPF contributes to the Fawn Trough Current identified by previous studies. After exiting the Fawn Trough, the SPF crossed Chun Spur and continued as a strong north-westward flowing jet along the eastern flank of the Kerguelen Plateau before turning offshore between 50°S and 51.5°S. Measured bottom water temperatures suggest a deep water connection between the northern and southern parts of the eastern Kerguelen Plateau indicating that the deep western boundary current continues at least as far north as 50.5°S. Analysis of satellite altimetry derived SSH streamlines demonstrates a southward shift of both the northern and southern branches of the Polar Front from 1994 to 2004. In the direct vicinity of the Heard and McDonald islands, cool waters of southern origin flow along the Heard Island slope and through the Eastern Trough bringing cold Winter Water (WW) onto the plateau. Complex topography funnels flow through canyons, deepens the mixed layer and increases productivity, resulting in this area being the preferred foraging region for a number of satellite-tracked land-based predators.
McNeil, J Chase; Kok, Eric Y; Forbes, Andrea R; Lamberth, Linda; Hulten, Kristina G; Vallejo, Jesus G; Mason, Edward O; Kaplan, Sheldon L
2016-03-01
Elevated vancomycin minimum inhibitory concentrations (MICs) in Staphylococcus aureus have been associated with worse clinical outcomes in adults. For invasive meticillin-resistant S. aureus (MRSA) infections in adults, the Infectious Diseases Society of America recommends targeting vancomycin serum trough concentrations between 15 and 20 μg/mL. We evaluated trends in vancomycin MICs from healthcare-associated (HCA) S. aureus bacteremia isolates in children in addition to correlating vancomycin serum trough levels with clinical outcomes. Patients and isolates were identified from a prospective S. aureus surveillance study at Texas Children's Hospital (TCH). HCA S. aureus bacteremia isolates from 2003 to 2013 were selected. Vancomycin MICs by E-test were determined and medical records were reviewed. Acute kidney injury (AKI) was defined as doubling of the baseline serum creatinine. Three hundred forty-one isolates met inclusion criteria. We observed a reverse vancomycin creep among MRSA isolates in the study period with a decline in the proportion of isolates with vancomycin MIC ≥ 2 μg/mL (from 32.7% to 5.6%; P < 0.001). However, the proportion of MSSA isolates with MIC ≥ 2 μg/mL increased (from 2.9% to 9%; P = 0.04). Among patients who had vancomycin troughs performed, there was no difference in duration of bacteremia or fever with vancomycin trough >15 versus <15 μg/mL. A vancomycin trough >15 μg/mL was, however, an independent risk factor for AKI. Vancomycin MICs are shifting among HCA S. aureus bacteremia isolates with significant differences between MRSA and MSSA at TCH. Higher vancomycin troughs did not improve outcomes in pediatric HCA S. aureus bacteremia but were associated with increased nephrotoxicity. Further studies are needed to better understand optimal management of children with S. aureus bacteremia.
Impact of Month of Birth on the Risk of Development of Autoimmune Addison's Disease
Fichna, Marta; Mitchell, Anna L.; Napier, Catherine M.; Gan, Earn; Ruchała, Marek; Santibanez-Koref, Mauro; Pearce, Simon H.
2016-01-01
Context: The pathogenesis of autoimmune Addison's disease (AAD) is thought to be due to interplay of genetic, immune, and environmental factors. A month-of-birth effect, with increased risk for those born in autumn/winter months, has been described in autoimmune conditions such as type 1 diabetes and autoimmune thyroid disease. Objective: Month-of-birth effect was investigated in 2 independent cohorts of AAD subjects. Design, Setting, and Patients: The monthly distribution of birth in AAD patients was compared with that of the general population using the cosinor test. A total of 415 AAD subjects from the United Kingdom cohort were compared with 8 180 180 United Kingdom births, and 231 AAD subjects from the Polish cohort were compared with 2 421 384 Polish births. Main Outcome Measures: Association between month of birth and the susceptibility to AAD. Results: In the entire cohort of AAD subjects, month-of-birth distribution analysis showed significant periodicity with peak of births in December and trough in May (P = .028). Analysis of the odds ratio distribution based on month of birth in 2 cohorts of patients with AAD versus the general population revealed a December peak and May trough, and January peak and July trough, in the United Kingdom and Polish cohorts, respectively. Conclusion: For the first time, we demonstrate that month of birth exerts an effect on the risk of developing AAD, with excess risk in individuals born in winter months and a protective effect when born in the summer. Exposure to seasonal viral infections in the perinatal period, coupled with vitamin D deficiency, could lead to dysregulation of innate immunity affecting the risk of developing AAD. PMID:27575942
NASA Astrophysics Data System (ADS)
Tudge, J.; Webb, S. I.; Tobin, H. J.
2013-12-01
Since 2007 the Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE) has drilled a total of 15 sites across the Nankai Trough subduction zone, including two sites on the incoming sediments of the Philippine Sea plate (PSP). Logging-while-drilling (LWD) data was acquired at 11 of these sites encompassing the forearc Kumano Basin, upper accretionary prism, toe region and input sites. Each of these tectonic domains is investigated for changes in physical properties and LWD characteristics, and this work fully integrates a large data set acquired over multiple years and IODP expeditions, most recently Expedition 338. Using the available logging-while-drilling data, primarily consisting of gamma ray, resistivity and sonic velocity, a log-based lithostratigraphy is developed at each site and integrated with the core, across the entire NanTroSEIZE transect. In addition to simple LWD characterization, the use of Iterative Non-hierarchical Cluster Analysis (INCA) on the sites with the full suite of LWD data clearly differentiates the unaltered forearc and slope basin sediments from the deformed sediments of the accretionary prism, suggesting the LWD is susceptible to the subtle changes in the physical properties between the tectonic domains. This differentiation is used to guide the development of tectonic-domain specific physical properties relationships. One of the most important physical property relationships between is the p-wave velocity and porosity. To fully characterize the character and properties of each tectonic domain we develop new velocity-porosity relationships for each domain found across the NanTroSEIZE transect. This allows the porosity of each domain to be characterized on the seismic scale and the resulting implications for porosity and pore pressure estimates across the plate interface fault zone.
NASA Astrophysics Data System (ADS)
Urgeles, R.; Llopart, J.; Lucchi, R.; Rebesco, M.; Brückner, N. W.; Rüther, D. C.; Lantzsch, H.
2017-12-01
Submarine slope instability plays a major role in the development of Arctic Trough Mouth Fans (TMFs). TMFs consist of an alternation of rapidly deposited glacigenic debris flows and a sequence of well-layered plumites and hemipelagic sediments. In this sedimentary context, shallow geophysical data and core samples indicate that there is a specific timing (i.e. shortly after the deglaciation phase) for the occurrence of slope failures. High mean sedimentation rates during glacial maxima of up to 18 kg m-2 yr-1 likely allow excess pore pressure to develop in the water rich plumites and hemipelagic sediments deposited in the previous deglacial period, particularly where such plumites attain a significant thickness. Basin numerical models considering the effect of (1) sediment physical properties, (2) polar margin architecture and (3) ice stream sediment dispersal patterns on resulting stresses, fluid flow and slope failure initiation of the Storfjorden Trough Mouth Fan, NW Barents Sea, show that during glacial maxima, ice streams and rapid accumulation of glacigenic debris flows on the slope induce pore pressure build-up in continental shelf/upper slope sediments. The overpressure developed during glacial maxima remains during the deglacial phase. This overpressure combined with downslope stratification of high water content and low shear strength deglacial/interglacial sediments results in a significant decrease in the factor of safety of the upper slope sediments. The position of the submarine landslides in the stratigraphic record suggest, however, that such excess pore pressure is not enough to trigger the slope failures and indicate that earthquakes related to isostatic rebound are likely involved in the final activation.
Balancing vancomycin efficacy and nephrotoxicity: should we be aiming for trough or AUC/MIC?
Patel, Karisma; Crumby, Ashley S; Maples, Holly D
2015-04-01
Sixty years later, the question that still remains is how to appropriately utilize vancomycin in the pediatric population. The Infectious Diseases Society of America published guidelines in 2011 that provide guidance for dosing and monitoring of vancomycin in adults and pediatrics. However, goal vancomycin trough concentrations of 15-20 μg/mL for invasive infections caused by methicillin-resistant Staphylococcus aureus were based primarily on adult pharmacokinetic and pharmacodynamic data that achieved an area under the curve to minimum inhibitory concentration ratio (AUC/MIC) of ≥400. Recent pediatric literature shows that vancomycin trough concentrations needed to achieve the target AUC/MIC are different than the adult goal troughs cited in the guidelines. This paper addresses several thoughts, including the role of vancomycin AUC/MIC in dosing strategies and safety monitoring, consistency in laboratory reporting, and future directions for calculating AUC/MIC in pediatrics.
Formations in Context (or, what is it?)
2018-04-02
This image from NASA's Mars Reconnaissance Orbiter is a close-up of a trough, along with channels draining into the depression. Some HiRISE images show strange-looking formations. Sometimes it helps to look at Context Camera images to understand the circumstances of a scene -- like this cutout from CTX 033783_1509 -- which here shows an impact crater with a central peak, and a collapse depression with concentric troughs just north of that peak. On the floor of the trough is some grooved material that we typically see in middle latitude regions where there has been glacial flow. These depressions with concentric troughs exist elsewhere on Mars, and their origins remain a matter of debate. NB: The Context Camera is another instrument onboard MRO, and it has a larger viewing angle than HiRISE, but less resolution capability than our camera. https://photojournal.jpl.nasa.gov/catalog/PIA22348
Oblique H.F. radiowave propagation in the main trough region of the ionosphere
NASA Astrophysics Data System (ADS)
Lockwood, M.; Mitchell, V. B.
1980-12-01
The propagation of 7.335 MHz, CW signals over a 5212 km subauroral, west-east path is studied. Measurements and semiempirical predictions are made of the amplitude distributions and Doppler shifts of the received signals. The observed amplitude distribution is fitted with a numerical fading model, yielding the power losses suffered by the signals during propagation via the predominating modes. The mid-latitude trough in the F2 peak ionization density is predicted by a statistical model to be at the latitudes of this path at these times and at low K sub p values; a sharp cut-off in low-power losses at a mean K sub p of 2.75 strongly implicates the trough in the propagation of these signals. It is shown that a simple extension of this model to allow for the trough can reproduce the form of the observed diurnal variation.
Huang, Wan-Ru; Wang, Sheng-Hsiang; Yen, Ming-Cheng; Lin, Neng-Huei; Promchote, Parichart
2016-09-16
During March and April, widespread burning occurs across farmlands in Indochina in preparation for planting at the monsoon onset. The resultant aerosols impact the air quality downwind. In this study, we investigate the climatic aspect of the interannual variation of springtime biomass burning in Indochina and its correlation with air quality at Mt. Lulin in Taiwan using long-term (2005-2015) satellite and global reanalysis data. Based on empirical orthogonal function (EOF) analysis, we find that the biomass burning activities vary with two geographical regions: northern Indochina (the primary EOF mode) and southern Indochina (the secondary EOF mode). We determine that the variation of biomass burning over northern Indochina is significantly related with the change in aerosol concentrations at Mt. Lulin. This occurs following the change in the so-called India-Burma Trough in the lower and middle troposphere. When the India-Burma Trough is intensified, a stronger northwesterly wind (to the west of the trough) transports the dryer air from higher latitude into northern Indochina, and this promotes local biomass burning activities. The increase in upward motion to the east of the intensified India-Burma Trough lifts the aerosols, which are transported toward Taiwan by the increased low-level westerly jet. Further diagnoses revealed the connection between the India-Burma Trough and the South Asian jet's wave train pattern as well as the previous winter's El Niño - Southern Oscillation phase. This information highlights the role of the India-Burma Trough in modulating northern Indochina biomass burning and possibly predicting aerosol transport to East Asia on the interannual time scale.
On the role of successive downstream development in East Asian polar air outbreaks
NASA Technical Reports Server (NTRS)
Jung, C. H.; Hitchman, M. H.
1982-01-01
Common features were drawn from 16 events of wintertime migration of cold Siberian air moving southeastward across the east Asia coast, accompanied by strong northerly winds. Criteria for including an event as an instance of a typical synoptic scale occurrence comprised a surface pressure gradient over Korea exceeding 2.5 mb/100 km, and a drop in the daily mean temperature of over 5 C in one day. The events were required to have at least a 10 day separation. A sequence of events was discerned, including the formation of troughs and ridges over the western north Atlantic 6-7 days before an event, their development and decay downstream from one another across the Eurasian continent, and then an outbreak of polar weather. The troughs and ridges displayed maximum amplitude in the same places in the majority of cases studied, with the center moving along a curved trajectory of the 300 mb flow at nearly 30 deg longitudinally every day.
NASA Astrophysics Data System (ADS)
Horvath, Anita; Bada, Gabor; Szafian, Peter; Sztano, Orsolya; Law, Ben; Wallis, Rod
2010-05-01
The latest phase exploration in the Makó Trough, which commenced a few years ago, has focused on the utilization of unconventional hydrocarbons. Accumulations are regarded as "unconventional" when they cannot be produced economically except by means of some sort of stimulation, usually hydraulic fracturing. The model we have developed for the evaluation of the hydrocarbon potential indicates a significant gas accumulation in the area of the Makó Trough. The tally of the distinctive attributes of the hydrocarbon system and the combined analysis of the available geological data led to the conclusion that the Makó Trough represents an area of active basin-centered gas accumulation (BCGA), with very significant perspective reserves. In a BCGA, hydrocarbons do not accumulate conventionally, in structural or stratigraphic traps, but rather in cells. Due to the geological setting of the Makó Trough, the hydrocarbon cell here forms a relatively continuous zone marked by considerable internal lithological and petrophysical variability. The most prolific parts, called sweet spots, possess a reservoir potential higher than the average. The identification of these sweet spots constitutes one of the most important, and quite possibly the most challenging task of the entire exploration project. The hemipelagic Endrőd Formation, which acts as the source rock, contains organic-rich marls in a depth delimited by the 170-230 °C isotherms. These marls constitute the still active hydrocarbon "kitchen" of the BCGA in the Makó Trough. The top and bottom boundaries of the cell essentially coincide with the turbidites of the Szolnok Formation and the top of the pre-Neogene basement, respectively. In light of the fact that pressure, temperature, and maturity tests have produced rather similar results in a number of wells in the area, we have reason to believe that the extension of the Makó Trough's BCGA is of regional dimensions (>1000 km2). The thickness and lateral extension of the potential reservoirs yield a cell volume as great as several hundred km3 - the largest single prospective gas occurrence in Hungary to date. Due to its novelty and complexity, the exploration of this unconventional resource demands the concurrent application of a wider range of geological and geophysical methods. In this presentation, we use selected examples to give an idea of where we stand on the way toward understanding the Makó Trough, particularly in terms of the geometric and structural features of the basin, the depositional (basin-fill) processes, and of the maturation history and accumulation properties of hydrocarbons. The geophysical surveys were purpose-designed to enable the mapping of the deep sedimentary trough and the sediments deposited in it. The data acquired to date suggest that the basin-centered gas accumulation occurred in the Lower Pannonian strata (11-6? Ma). Interpreting the 3D seismic data, the structural features and sedimentology of the basin can be studied in excellent resolution, while the integration of the seismic information with the geological data obtained from the wells allows us to interpret local well information extensively to gain a deeper, three-dimensional understanding of the basin. The sedimentary sequence filling up the Makó Trough displays distinct stratigraphic units separated by unconformities. Mapping the top of the pre-Neogene basement provides valuable insight into the nature of the paleo-geomorphological elements and the sedimentary environment at the onset of rifting. Paleontological information dates the syn-rift sediments of the trough to the Late Miocene (Early Pannonian), suggesting that the most intensive phase of basin evolution here was delayed by a few million years compared to adjacent areas. For the environmental reconstruction of the post-rift sedimentary sequence, we start with the assumption that initially a starved basin existed here, where sedimentation could not keep up with the rate of subsidence (Endrőd Formation). The basin was then almost completely filled by the turbidites of a prograding delta system (Szolnok Formation), followed by the sediments from the pro-delta (Algyő Formation) and the delta plain (Újfalu Formation). During the Plio- and Pleistocene, the area continued to subside at a decreased rate, providing a limited accumulation space filled by a thick sequence of alluvial deposits similar to the paleo-environment of the Tisza River and its tributaries prior to regulation. Our modeling of basin evolution in terms of subsidence, thermal and maturation history based on the results of geochemical, petrophysical, and paleontological investigations reveals that the organic matter accumulated in the trough underwent exceptionally rapid maturation during the last 5 to 7 million years. In fact, source rocks continue to mature at present time, and the hydrocarbons they generate continue to migrate and trap. The rather young age of the Pannonian Basin and its hydrocarbon system makes it quite different from the other examples of basin-centered gas accumulation, such as the classic Rocky Mountains in the U.S., or the Karoo Basin in South Africa, the Beetaloo Basin in Australia, making up the exploration portfolio of Falcon.
NASA Astrophysics Data System (ADS)
Horikawa, H.; Takaesu, M.; Sueki, K.; Araki, E.; Sonoda, A.; Takahashi, N.; Tsuboi, S.
2015-12-01
The Nankai Trough in southwest Japan is one of most active subduction zone in the world. Great mega-thrust earthquakes repeatedly occurred every 100 to 150 years in this area, it's anticipated to occur in the not distant future. For the purpose of elucidation of the history of mega-splay fault activity, the physical properties of the geological strata and the internal structure of the accretionary prism, and monitoring of diastrophism in this area, we have a plan, Nankai Trough Seismogenic Zone Experiments (NanTroSEIZE), as a part of Integrated Ocean Drilling Program (IODP).We have a plan to install the borehole observation system in a few locations by the NanTroSEIZE. This system is called Long-Term Borehole Monitoring System, it consists of various sensors in the borehole such as a broadband seismometer, a tiltmeter, a strainmeter, geophones and accelerometer, thermometer array as well as pressure ports for pore-fluid pressure monitoring. The signal from sensors is transmitted to DONET (Dense Ocean-floor Network System for Earthquake and Tsunamis) in real-time. During IODP Exp. 332 in December 2010, the first Long-Term Borehole Monitoring System was installed into the C0002 borehole site located 80 km off the Kii Peninsula, 1938 m water depth in the Nankai Trough.We have developed a web application system for data download, Long-Term Borehole Monitoring Data Site (*1). Based on a term and sensors which user selected on this site, user can download monitoring waveform data (e.g. broadband seismometer data, accelerometer data, strainmeter data, tiltmeter data) in near real-time. This system can make the arbitrary data which user selected a term and sensors, and download it simply. Downloadable continuous data is provided in seed format, which includes sensor information. In addition, before data download, user can check that data is available or not by data check function.In this presentation, we briefly introduce NanTroSEIZE and then show our web application system. We also discuss our future plans for developments of monitoring data download system.*1 Long-Term Borehole Monitoring Data Site http://join-web.jamstec.go.jp/borehole/borehole_top_e.html
Landslides in Valles Marineris, Mars.
Lucchitta, B.K.
1979-01-01
Large landslides in the Martian equatorial troughs have been investigated with respect to morphology, geologic structure of the troughs, time of emplacement, similarity to terrestrial landslides, and origin and mechanism of transport. The morphologic variations of the landslides can be attributed mainly to their degree of confinement on trough floors. The huge size of many landslides is due to their occurrence on fault scarps that may have attained several kilometers in height in the absence of vigorous fluvial erosion on Mars. The mechanical efficiency of the Martian landslides is high but in accord with predictions from large landslides on earth. -from Author
Baby Spider: Growth of a Martian Trough Network
2016-12-20
This image from NASA Mars Reconnaissance Orbiter shows the growth of a branching network of troughs carved by thawing carbon dioxide over the span of three Martian years. This process is believed to also form larger radially patterned channel features known as Martian "spiders." The image is one of three taken by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter and included in a report on the first detection of such troughs persisting and growing, from one Mars year to the next. An animation is available at http://photojournal.jpl.nasa.gov/catalog/PIA21257
NASA Astrophysics Data System (ADS)
Reddy, K. S.; Singla, Hitesh
2017-07-01
In the present work, structural analysis of 5.77m × 4m woven jute (J)/glass (G) fibre-reinforced polyester hybrid composite solar parabolic trough is carried out based on trough parameters to obtain the minimum RMS local slope deviation, termed as SDx value under gravity loading. The optimization is done by varying parameters viz. direction and size of reinforced conduits, stacking number and sequence of hybrid trough laminate at fibre orientation of Δθ=45° and Δθ=60° amongst the layers at 0° collector angle. The analysis revealed that the configuration in which the conduits are placed in both X and Y directions is preferred over other configurations to scale down the effect of wind loads. Furthermore it has been observed that laminate of the order [0°G/45°G/-45°J/90°J]s undergoes minimum surface deformation amongst all the other configurations at conduit reinforcement in both X and Y directions for a conduit thickness of 0.75 mm and radius of 10 mm and obtains the overall SDx value of 1.3492 mrad. The results shows that proposed trough model is very promising and evolves a cost effective system.
Investigating the reasons of variability in Si IV and C IV broad absorption line troughs of quasars
NASA Astrophysics Data System (ADS)
Stathopoulos, Dimitrios; Lyratzi, Evangelia; Danezis, Emmanuel; Antoniou, Antonios; Tzimeas, Dimitrios
2017-09-01
In this paper we analyze the C IV and Si IV broad absorption troughs of two BALQSOs (J101056.69+355833.3, J114548.38+393746.6) to the individual components they consist of. By analyzing a BAL trough to its components we have the advantage to study the variations of the individual absorbing systems in the line of sight and not just the variations of the whole absorption trough or the variations of selected portions of BAL troughs exhibiting changes. We find that the velocity shifts and FWHMs (Full Width at Half Maximum) of the individual components do not vary between an interval of six years. All variable components show changes in the optical depths at line centers which are manifested as variations in the EW (Equivalent Width) of the components. In both BALQSOs, over corresponding velocities, Si IV has higher incidence of variability than C IV. From our analysis, evidence is in favour of different covering fractions between C IV and Si IV. Finally, although most of our results favour the crossing cloud scenario as the cause of variability, there is also strong piece of evidence indicating changing ionization as the source of variability. Thus, a mixed situation where both physical mechanisms contribute to BAL variability is the most possible scenario.
Takeuchi, Akiko; Shirai, Shinichi; Horiuchi, Kazuhiro; Takahashi, Ikuko; Matsushima, Masaaki; Hirotani, Makoto; Kano, Takahiro; Yabe, Ichiro; Matumoto, Akihisa; Sasaki, Hidenao
2012-01-01
Cyclosporine A (CYA) treatment has been reported to be probably useful for patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) that is resistant to conventional treatment. Although several studies have shown that appropriate area under the concentration-time curve (AUC) monitoring of CYA levels results in improved outcomes for refractory nephrotic syndrome patients, the importance of using AUC analysis for CIDP remains unclear. In this study, we measured both trough and AUC from 0 to 4 h (AUC(0-4 h)) levels of CYA in 2 patients with CIDP and compared the findings for the clinical parameters. On the basis of the CYA dosing recommendations for patients with nephrotic syndrome, we used a CYA concentration of 150 ng/ml for the trough level and an AUC(0-4 h) value of 2,500 ng/(ml·h). Patient 1 showed a significant increase in grip strength and a prolonged remission period. Patient 2 showed improvement in the modified Rankin scale and manual muscle test (MMT) scores. Monitoring both AUC(0-4 h) and trough levels of CYA seems to be a better option than monitoring the trough level alone because it leads to improved estimation of the efficacy and safety of CYA treatment in the case of CIDP patients.
Raybould, J N; Barro, T; Sawadogo, R; Mordzifa, F
1982-06-01
Laboratory rearing of Simulium damnosum complex species enables female adults to be indirectly identified from their larval progeny. A simple, readily transportable rearing apparatus was developed for investigations by the Onchocerciasis Control programme by using unbreakable, easily packed and reassembled parts and by feeding the larvae at least partly with living green algae (Chlorophyceae) cultured in the laboratory. Although the larvae are sensitive to excess nitrogen compounds, the use of algae and a large volume of water obviated the need for a separate purification system in which water was circulated by an A/C electrical centrifugal pump between a container and an inclined trough in which most of the larvae developed. The rate of development was rapid giving rise to full size larvae (suitable for cytotaxonomic determination), pupae and adults. The adults were attracted into a collecting device by light. Developments to protect the larvae during electrical power failures included a slow-drying wooden rearing trough and an automatic switch to an alternative D/C power supply and pump. This technique has been in general use in O.C.P. laboratories in Benin, Ghana, Ivory Coast and Upper Volta and many thousands of larvae have been reared.
Forearc sedimentation in Terraba Trough, Costa Rica, Central America
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yuan, P.B.; Lowe, D.R.
1987-05-01
Sedimentary rocks of Terraba Trough, Costa Rica, were deposited in a forearc basin developed at an ocean-ocean convergent boundary. The basin developed in the middle to late Eocene when the Farallon plate began its subduction beneath the Caribbean plate. Shallow-water carbonates of the Brito Formation were deposited on shoals of basement blocks. These were surrounded by deeper marine areas in which volcaniclastics and carbonate debris accumulated. The Brito Formation consists of algal-foraminiferal packstone to grainstone, rudstone, and rare wackestone formed in fore-slope, carbonate buildup, and open platform environments in a warm, tropical sea. The Eocene Brito Formation is overlain bymore » rocks of the upper Oligocene Rio Claro Member of the Terraba Formation. It is composed of rhodolite and bioclastic grainstone deposited in shallow water. A combination of little subsidence, mild volcanism, and possible erosion at about 30 Ma during a global drop of sea level may be responsible for the absence of lower Oligocene rocks in the study area. After the deposition of the Rio Claro Member, the area subsided rapidly to become a trough possibly deeper than 2000 m. Sedimentation took place in deep water from sediment gravity flows. In the early to early middle Miocene, coarser sediments and thicker sand units containing coal fragments became more abundant, suggesting that the basin was gradually filled. This study indicates that the timing and degree of subsidence of the fore-arc basin and the vertical variation in lithology are closely related to the variation in convergence rate between lithospheric plates in this part of Central America and the eastern Pacific.« less
Multiple-Panel Cylindrical Solar Concentrator
NASA Technical Reports Server (NTRS)
Brown, E. M.
1983-01-01
Trough composed of many panels concentrates Sun's energy on solar cells, even when trough is not pointed directly at Sun. Tolerates deviation as great as 5 degrees from direction of sun. For terrestrial applications, multiple-flat-plate design offers potential cost reduction and ease of fabrication.
Assessment of undiscovered continuous oil and gas resources in the Hanoi Trough, Vietnam, 2017
Schenk, Christopher J.; Tennyson, Marilyn E.; Mercier, Tracey J.; Woodall, Cheryl A.; Le, Phuong A.; Klett, Timothy R.; Finn, Thomas M.; Leathers-Miller, Heidi M.; Gaswirth, Stephanie B.; Marra, Kristen R.
2018-02-13
Using a geology-based assessment methodology, the U.S. Geological Survey estimated mean undiscovered, technically recoverable continuous resources of 52 million barrels of oil and 591 billion cubic feet of gas in the Hanoi Trough of Vietnam.
NASA Astrophysics Data System (ADS)
Li, Wei; Alves, Tiago M.; Wu, Shiguo; Rebesco, Michele; Zhao, Fang; Mi, Lijun; Ma, Benjun
2016-10-01
A giant submarine creep zone exceeding 800 km2 on the continental slope offshore the Dongsha Islands, South China Sea, is investigated using bathymetric and 3D seismic data tied to borehole information. The submarine creep zone is identified as a wide area of seafloor undulations with ridges and troughs. The troughs form NW- and WNW-trending elongated depressions separating distinct seafloor ridges, which are parallel or sub-parallel to the continental slope. The troughs are 0.8-4.7 km-long and 0.4 to 2.1 km-wide. The ridges have wavelengths of 1-4 km and vertical relief of 10-30 m. Slope strata are characterised by the presence of vertically stacked ridges and troughs at different stratigraphic depths, but remaining relatively stationary in their position. The interpreted ridges and troughs are associated with large-scale submarine creep, and the troughs can be divided into three types based on their different internal characters and formation processes. The large-scale listric faults trending downslope below MTD 1 and horizon T0 may be the potential glide planes for the submarine creep movement. High sedimentation rates, local fault activity and the frequent earthquakes recorded on the margin are considered as the main factors controlling the formation of this giant submarine creep zone. Our results are important to the understanding of sediment instability on continental slopes as: a) the interpreted submarine creep is young, or even active at present, and b) areas of creeping may evolve into large-scale slope instabilities, as recorded by similar large-scale events in the past.
Gas potential of the Rome Trough in Kentucky: Results of recent Cambrian exploration
DOE Office of Scientific and Technical Information (OSTI.GOV)
Harris, D.C.; Drahovzal, J.A.
1996-09-01
A recent gas discovery in the Rome Trough suggests the need to re-evaluate the deep Cambrian potential of eastern Kentucky. A new phase of Cambrian exploration began in mid-1994 with a new pool discovery by the Carson Associates No. 1 Kazee well in Elliott County, Ky. This well blew out and initially flowed 11 MMcfd of gas from the upper Conasauga Group/Rome Formation at 6,258 to 6,270 feet. After this discovery, a second exploratory well (the Blue Ridge No. 1Greene) was drilled on a separate structure in Elliott County in late 1995. The Blue Ridge well was temporarily abandoned, butmore » had shows of gas and condensate. In early 1996, Carson Associates offset their initial discovery well with the No. 33 Lawson Heirs well. This activity follows a frustrating exploration history in the Rome Trough that is marked by numerous gas and oil shows, but rare commercial production. Only three single-well pools have produced commercial gas from the trough, including the recent Kazee well. Stratigraphic units below the Cambrian-Ordovician Knox Group in the Rome Trough are dramatically thicker than their equivalents on the shelf to the north. The interval in the trough is thought to include rocks as old as Early Cambrian, consisting of a basal sandstone, equivalents of the Shady/Tomstown Dolomite, the Rome Formation, and the Conasauga Formation. Sandstones and fractured shales have been responsible for most of the production to date, but dolostone intervals may also have potential. Limited seismic data indicate possible fan-delta and basin-floor fan deposits that may have reservoir potential.« less
NASA Astrophysics Data System (ADS)
Tomaru, Hitoshi; Fehn, Udo
2015-01-01
Halogen concentrations and 129I/I ratios were determined in pore waters from the Nankai Trough subduction system, collected during IODP Expeditions 315, 316, 322, and 333 along the NanTroSEIZE transect. The transect allowed the first direct comparison of iodine results across an active subduction system, from subducting oceanic sediments to the accretionary prism, and the overlying forearc basin. In contrast to the other halogens (Cl and Br) iodine concentrations show large variations within and among the cores at all sites landward of the trough, I concentrations increase rapidly with depth and reach values several orders of magnitude higher than those in seawater, but are only slightly higher than seawater values at the seaward sites. Methane concentrations follow a similar pattern. Host sediments of the fluids are younger than 7 Ma in all the cores, but the ages of iodine in pore waters at the landward sites reach values beyond 30 Ma. In contrast, iodine seaward of the trough is in isotopic equilibrium with the host sediments, resulting in very similar iodine and sediment ages. The distribution of iodine concentrations and ages indicates that iodine at the landward sites has been transported there in aqueous fluids, probably together with methane, from old formations in the upper plate. The specific fluid pathways potentially were influenced by features such as the megasplay fault in the prism or the décollement. The results demonstrate large-scale transport of fluids carrying iodine and other compounds such as methane from old layers in the upper plate to surface locations landward of the Nankai Trough, while separate, but only local hydrologic processes occur in the marine sediments moving toward the trough.
Ribic, C.A.; Chapman, E.; Fraser, William R.; Lawson, G.L.; Wiebe, P.H.
2008-01-01
A key hypothesis guiding the US Southern Ocean Global Ocean Ecosystems Dynamics (US SO GLOBEC) program is that deep across-shelf troughs facilitate the transport of warm and nutrient-rich waters onto the continental shelf of the Western Antarctic Peninsula, resulting in enhanced winter production and prey availability to top predators. We tested aspects of this hypothesis during austral winter by assessing the distribution of the resident pack-ice top predators in relation to these deep across-shelf troughs and by investigating associations between top predators and their prey. Surveys were conducted July-August 2001 and August-September 2002 in Marguerite Bay, Antarctica, with a focus on the main across-shelf trough in the bay, Marguerite Trough. The common pack-ice seabird species were snow petrel (Pagodroma nivea, 1.2 individuals km-2), Antarctic petrel (Thalassoica antarctica, 0.3 individuals km-2), and Ade??lie penguin (Pygoscelis adeliae, 0.5 individuals km-2). The most common pack-ice pinniped was crabeater seal (Lobodon carcinophagus). During both winters, snow and Antarctic petrels were associated with low sea-ice concentrations independent of Marguerite Trough, while Ade??lie penguins occurred in association with this trough. Krill concentrations, both shallow and deep, also were associated with Ade??lie penguin and snow petrel distributions. During both winters, crabeater seal occurrence was associated with deep krill concentrations and with regions of lower chlorophyll concentration. The area of lower chlorophyll concentrations occurred in an area with complex bathymetry close to land and heavy ice concentrations. Complex or unusual bathymetry via its influence on physical and biological processes appears to be one of the keys to understanding how top predators survive during the winter in this Antarctic region. ?? 2007 Elsevier Ltd. All rights reserved.
Tseng, Sheng-Hsuan; Lim, Chuan Poh; Chen, Qi; Tang, Cheng Cai; Kong, Sing Teang; Ho, Paul Chi-Lui
2018-04-01
Bacterial sepsis is a major cause of morbidity and mortality in neonates, especially those involving methicillin-resistant Staphylococcus aureus (MRSA). Guidelines by the Infectious Diseases Society of America recommend the vancomycin 24-h area under the concentration-time curve to MIC ratio (AUC 24 /MIC) of >400 as the best predictor of successful treatment against MRSA infections when the MIC is ≤1 mg/liter. The relationship between steady-state vancomycin trough concentrations and AUC 24 values (mg·h/liter) has not been studied in an Asian neonatal population. We conducted a retrospective chart review in Singapore hospitals and collected patient characteristics and therapeutic drug monitoring data from neonates on vancomycin therapy over a 5-year period. A one-compartment population pharmacokinetic model was built from the collected data, internally validated, and then used to assess the relationship between steady-state trough concentrations and AUC 24 A Monte Carlo simulation sensitivity analysis was also conducted. A total of 76 neonates with 429 vancomycin concentrations were included for analysis. Median (interquartile range) was 30 weeks (28 to 36 weeks) for postmenstrual age (PMA) and 1,043 g (811 to 1,919 g) for weight at the initiation of treatment. Vancomycin clearance was predicted by weight, PMA, and serum creatinine. For MRSA isolates with a vancomycin MIC of ≤1, our major finding was that the minimum steady-state trough concentration range predictive of achieving an AUC 24 /MIC of >400 was 8 to 8.9 mg/liter. Steady-state troughs within 15 to 20 mg/liter are unlikely to be necessary to achieve an AUC 24 /MIC of >400, whereas troughs within 10 to 14.9 mg/liter may be more appropriate. Copyright © 2018 American Society for Microbiology.
Morcos, Peter N; Nueesch, Eveline; Jaminion, Felix; Guerini, Elena; Hsu, Joy C; Bordogna, Walter; Balas, Bogdana; Mercier, Francois
2018-05-10
Alectinib is a selective and potent anaplastic lymphoma kinase (ALK) inhibitor that is active in the central nervous system (CNS). Alectinib demonstrated robust efficacy in a pooled analysis of two single-arm, open-label phase II studies (NP28673, NCT01801111; NP28761, NCT01871805) in crizotinib-resistant ALK-positive non-small-cell lung cancer (NSCLC): median overall survival (OS) 29.1 months (95% confidence interval [CI]: 21.3-39.0) for alectinib 600 mg twice daily (BID). We investigated exposure-response relationships from final pooled phase II OS and safety data to assess alectinib dose selection. A semi-parametric Cox proportional hazards model analyzed relationships between individual median observed steady-state trough concentrations (C trough,ss ) for combined exposure of alectinib and its major metabolite (M4), baseline covariates (demographics and disease characteristics) and OS. Univariate logistic regression analysis analyzed relationships between C trough,ss and incidence of adverse events (AEs: serious and Grade ≥ 3). Overall, 92% of patients (n = 207/225) had C trough,ss data and were included in the analysis. No statistically significant relationship was found between C trough,ss and OS following alectinib treatment. The only baseline covariates that statistically influenced OS were baseline tumor size and prior crizotinib treatment duration. Larger baseline tumor size and shorter prior crizotinib treatment were both associated with shorter OS. Logistic regression confirmed no significant relationship between C trough,ss and AEs. Alectinib 600 mg BID provides systemic exposures at plateau of response for OS while maintaining a well-tolerated safety profile. This analysis confirms alectinib 600 mg BID as the recommended global dose for patients with crizotinib-resistant ALK-positive NSCLC.
NASA Astrophysics Data System (ADS)
Clary, W. A.; Worthington, L. L.; Daigle, H.; Slagle, A. L.; Gulick, S. P. S.
2016-12-01
Sediments offshore Southern Alaska offer a natural laboratory to study glacial erosion, sediment deposition, and orogenesis. A major goal of Integrated Ocean Drilling Program (IODP) Expedition 341 was investigation of interrelationships among tectonic processes, paleoclimate, and glacial activity. Here, we focus on core-log-seismic integration of IODP Sites U1420 and U1421 on the shallow shelf and slope near the Bering Trough, a glacially derived shelf-crossing landform. These sites sample glacial and marine sediments that record a history of sedimentation following the onset of glacial intensification near the mid-Pleistocene transition (1.2 Ma) and Yakutat microplate convergence with North America. Ocean drilling provides important stratigraphic, physical properties, and age data in depth which support development of a stratigraphic model that can be extended across the shelf if carefully calibrated to local and regional seismic surveys. We use high resolution multichannel seismic, core, and logging data to develop a time-depth relationship (TDR) and update the developing chronostratigraphic model based on correlation of seismic sequence boundaries and drilling-related data, including biostratigraphic and paleomagnetic age controls. We calibrate, combine, and interpolate core and logging data at each site to minimize gaps in physical property information and generate synthetic seismic traces. At Site U1421, vertical seismic profiling further constrains the TDR, and provides input for the initial velocity model during the tie. Finally, we match reflectors in the synthetic trace with events in nearby seismic reflection data to establish a TDR at each site. We can use this relationship to better interpret the development of the Bering Trough, a recurring and favored path for ice streams and glacial advance. Initial results suggest late Pleistocene sedimentation rates of at least 1 km/m.y. on average, and variable sedimentation rates which are possibly correlated with paleoenvironmental indicators such as sea ice related species of diatoms.
NASA Astrophysics Data System (ADS)
Baldwin, Guillermo; Gonzales, Franco; Pérez S., Carlos
2017-11-01
In Peru, as in almost all Latin America, precision optical industry is almost null. One reason is the scarcity of human and technological resources. But, a few years ago, a masters and diploma university program in optical engineering was started in our university: Pontificia Universidad Católica del Perú1 (PUCP) in Lima. Also, an optical shop on precision optics was implemented. Some students were trained at CIO in Leon, Mexico. In order to motivate optical business startups in Peru we planned to show some possibilities of optical devices fabrication trough doing prototypes. So, we started doing a small reflective telescope for moon observation2, 3, where mirror and ocular polishing and opto-mechanics had priority. Aluminum evaporation was included. Now, we do a new step developing a binocular, as we know, it never was made before in Peru. This work includes the binocular geometric optics and opto-mechanical designs, the ocular manufacturing, and the binocular characterization of an 8x35 binocular for amateur observation.
Hazard assessment of long-period ground motions for the Nankai Trough earthquakes
NASA Astrophysics Data System (ADS)
Maeda, T.; Morikawa, N.; Aoi, S.; Fujiwara, H.
2013-12-01
We evaluate a seismic hazard for long-period ground motions associated with the Nankai Trough earthquakes (M8~9) in southwest Japan. Large interplate earthquakes occurring around the Nankai Trough have caused serious damages due to strong ground motions and tsunami; most recent events were in 1944 and 1946. Such large interplate earthquake potentially causes damages to high-rise and large-scale structures due to long-period ground motions (e.g., 1985 Michoacan earthquake in Mexico, 2003 Tokachi-oki earthquake in Japan). The long-period ground motions are amplified particularly on basins. Because major cities along the Nankai Trough have developed on alluvial plains, it is therefore important to evaluate long-period ground motions as well as strong motions and tsunami for the anticipated Nankai Trough earthquakes. The long-period ground motions are evaluated by the finite difference method (FDM) using 'characterized source models' and the 3-D underground structure model. The 'characterized source model' refers to a source model including the source parameters necessary for reproducing the strong ground motions. The parameters are determined based on a 'recipe' for predicting strong ground motion (Earthquake Research Committee (ERC), 2009). We construct various source models (~100 scenarios) giving the various case of source parameters such as source region, asperity configuration, and hypocenter location. Each source region is determined by 'the long-term evaluation of earthquakes in the Nankai Trough' published by ERC. The asperity configuration and hypocenter location control the rupture directivity effects. These parameters are important because our preliminary simulations are strongly affected by the rupture directivity. We apply the system called GMS (Ground Motion Simulator) for simulating the seismic wave propagation based on 3-D FDM scheme using discontinuous grids (Aoi and Fujiwara, 1999) to our study. The grid spacing for the shallow region is 200 m and 100 m in horizontal and vertical, respectively. The grid spacing for the deep region is three times coarser. The total number of grid points is about three billion. The 3-D underground structure model used in the FD simulation is the Japan integrated velocity structure model (ERC, 2012). Our simulation is valid for period more than two seconds due to the lowest S-wave velocity and grid spacing. However, because the characterized source model may not sufficiently support short period components, we should be interpreted the reliable period of this simulation with caution. Therefore, we consider the period more than five seconds instead of two seconds for further analysis. We evaluate the long-period ground motions using the velocity response spectra for the period range between five and 20 second. The preliminary simulation shows a large variation of response spectra at a site. This large variation implies that the ground motion is very sensitive to different scenarios. And it requires studying the large variation to understand the seismic hazard. Our further study will obtain the hazard curves for the Nankai Trough earthquake (M 8~9) by applying the probabilistic seismic hazard analysis to the simulation results.
NASA Technical Reports Server (NTRS)
2006-01-01
13 March 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a portion of a trough in the Sirenum Fossae region. On the floor and walls of the trough, large -- truck- to house-sized -- boulders are observed at rest. However, there is evidence in this image for the potential for mobility. In the central portion of the south (bottom) wall, a faint line of depressions extends from near the middle of the wall, down to the rippled trough floor, ending very near one of the many boulders in the area. This line of depressions is a boulder track; it indicates the path followed by the boulder as it trundled downslope and eventually came to rest on the trough floor. Because it is on Mars, even when the boulder is sitting still, this once-rolling stone gathers no moss. Location near: 29.4oS, 146.6oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern SummerNear-trench slip potential of megaquakes evaluated from fault properties and conditions
Hirono, Tetsuro; Tsuda, Kenichi; Tanikawa, Wataru; Ampuero, Jean-Paul; Shibazaki, Bunichiro; Kinoshita, Masataka; Mori, James J.
2016-01-01
Near-trench slip during large megathrust earthquakes (megaquakes) is an important factor in the generation of destructive tsunamis. We proposed a new approach to assessing the near-trench slip potential quantitatively by integrating laboratory-derived properties of fault materials and simulations of fault weakening and rupture propagation. Although the permeability of the sandy Nankai Trough materials are higher than that of the clayey materials from the Japan Trench, dynamic weakening by thermally pressurized fluid is greater at the Nankai Trough owing to higher friction, although initially overpressured fluid at the Nankai Trough restrains the fault weakening. Dynamic rupture simulations reproduced the large slip near the trench observed in the 2011 Tohoku-oki earthquake and predicted the possibility of a large slip of over 30 m for the impending megaquake at the Nankai Trough. Our integrative approach is applicable globally to subduction zones as a novel tool for the prediction of extreme tsunami-producing near-trench slip. PMID:27321861
Gangodagamage, Chandana; Wullschleger, Stan
2014-07-03
The dataset represents microtopographic characterization of the ice-wedge polygon landscape in Barrow, Alaska. Three microtopographic features are delineated using 0.25 m high resolution digital elevation dataset derived from LiDAR. The troughs, rims, and centers are the three categories in this classification scheme. The polygon troughs are the surface expression of the ice-wedges that are in lower elevations than the interior polygon. The elevated shoulders of the polygon interior immediately adjacent to the polygon troughs are the polygon rims for the low center polygons. In case of high center polygons, these features are the topographic highs. In this classification scheme, both topographic highs and rims are considered as polygon rims. The next version of the dataset will include more refined classification scheme including separate classes for rims ad topographic highs. The interior part of the polygon just adjacent to the polygon rims are the polygon centers.
A Geospatial Comparison of Distributed Solar Heat and Power in Europe and the US
Norwood, Zack; Nyholm, Emil; Otanicar, Todd; Johnsson, Filip
2014-01-01
The global trends for the rapid growth of distributed solar heat and power in the last decade will likely continue as the levelized cost of production for these technologies continues to decline. To be able to compare the economic potential of solar technologies one must first quantify the types and amount of solar resource that each technology can utilize; second, estimate the technological performance potential based on that resource; and third, compare the costs of each technology across regions. In this analysis, we have performed the first two steps in this process. We use physical and empirically validated models of a total of 8 representative solar system types: non-tracking photovoltaics, 2d-tracking photovoltaics, high concentration photovoltaics, flat-plate thermal, evacuated tube thermal, concentrating trough thermal, concentrating solar combined heat and power, and hybrid concentrating photovoltaic/thermal. These models are integrated into a simulation that uses typical meteorological year weather data to create a yearly time series of heat and electricity production for each system over 12,846 locations in Europe and 1,020 locations in the United States. Through this simulation, systems composed of various permutations of collector-types and technologies can be compared geospatially and temporally in terms of their typical production in each location. For example, we see that silicon solar cells show a significant advantage in yearly electricity production over thin-film cells in the colder climatic regions, but that advantage is lessened in regions that have high average irradiance. In general, the results lead to the conclusion that comparing solar technologies across technology classes simply on cost per peak watt, as is usually done, misses these often significant regional differences in annual performance. These results have implications for both solar power development and energy systems modeling of future pathways of the electricity system. PMID:25474632
A geospatial comparison of distributed solar heat and power in Europe and the US.
Norwood, Zack; Nyholm, Emil; Otanicar, Todd; Johnsson, Filip
2014-01-01
The global trends for the rapid growth of distributed solar heat and power in the last decade will likely continue as the levelized cost of production for these technologies continues to decline. To be able to compare the economic potential of solar technologies one must first quantify the types and amount of solar resource that each technology can utilize; second, estimate the technological performance potential based on that resource; and third, compare the costs of each technology across regions. In this analysis, we have performed the first two steps in this process. We use physical and empirically validated models of a total of 8 representative solar system types: non-tracking photovoltaics, 2d-tracking photovoltaics, high concentration photovoltaics, flat-plate thermal, evacuated tube thermal, concentrating trough thermal, concentrating solar combined heat and power, and hybrid concentrating photovoltaic/thermal. These models are integrated into a simulation that uses typical meteorological year weather data to create a yearly time series of heat and electricity production for each system over 12,846 locations in Europe and 1,020 locations in the United States. Through this simulation, systems composed of various permutations of collector-types and technologies can be compared geospatially and temporally in terms of their typical production in each location. For example, we see that silicon solar cells show a significant advantage in yearly electricity production over thin-film cells in the colder climatic regions, but that advantage is lessened in regions that have high average irradiance. In general, the results lead to the conclusion that comparing solar technologies across technology classes simply on cost per peak watt, as is usually done, misses these often significant regional differences in annual performance. These results have implications for both solar power development and energy systems modeling of future pathways of the electricity system.
Developing a Mouse Model of Sensory and Cognitive Deficits for Multiple Sclerosis
2013-07-01
the plot is essentially horizontal, indicating that these mutants cannot localize sounds in space. A well-known characteristic of signal flow ...the five characteristic peaks and troughs of the ABR arising from generators in the eighth cranial nerve, cochlear nucleus, SOC, lateral lemniscus and
Dreesen, Erwin; Verstockt, Bram; Bian, Sumin; de Bruyn, Magali; Compernolle, Griet; Tops, Sophie; Noman, Maja; Van Assche, Gert; Ferrante, Marc; Gils, Ann; Vermeire, Séverine
2018-04-25
Trough concentrations of vedolizumab were found to correlate with clinical response in phase 3 studies of patients with ulcerative colitis (UC) or Crohn's disease (CD). Nevertheless, there are no solid data to support monitoring of vedolizumab trough concentrations in treated patients. We investigated the correlation between vedolizumab exposure and response in a real-world population and aimed to identify patient factors that affect exposure and response. We performed a retrospective cohort study of 179 consecutive patients (66 with UC and 113 with CD) who began vedolizumab therapy from September 1, 2015, through October 1, 2016, at University Hospitals Leuven, Belgium. Serum concentrations of vedolizumab were measured before all infusions up to week 30. Effectiveness endpoints included endoscopic healing (UC, Mayo endoscopic sub-score ≤1; CD, absence of ulcers), clinical response (physicians' global assessment), and biologic response or remission (based on level of C-reactive protein) and were assessed at week 14 (for patients with UC) and week 22 (for patients with CD). A stepwise forward addition-backward elimination modeling approach was performed to identify factors independently associated with vedolizumab exposure and response. Vedolizumab trough concentrations >30.0 μg/mL at week 2, >24.0 μg/mL at week 6, and >14.0 μg/mL during maintenance therapy associated with a higher probability of attaining the effectiveness endpoints for patients with UC or CD (P < .05). Higher body mass and more severe disease (based on high level of C-reactive protein and low level of albumin and/or hemoglobin) at the start of vedolizumab therapy associated with lower trough concentrations of vedolizumab over the 30-week period and a lower probability of achieving mucosal healing (P < .05). Mucosal healing was achieved in significantly more patients with UC than patients with CD, even though a diagnosis of UC was not an independent predictor of higher vedolizumab trough concentrations. In a retrospective study of 179 patients with CD or UC, we observed a correlation between vedolizumab exposure and response. These findings support monitoring of vedolizumab trough concentrations to predict patients' outcome. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Saint-Ange, F.; Campbell, C.; MacKillop, K.; Mosher, D. C.; Piper, D. J.; Roger, J.
2012-12-01
Many studies have proposed that reactivation of dormant faults during deglaciation is a source of neotectonic activity in glaciated regions, but few have demonstrated the relationship to submarine landslides. In this study, seabed morphology and shallow geology of the outer continental margin adjacent to the Charlie Gibbs Fracture Zone off Newfoundland, Canada was investigated for evidence of this relationship. The glacial history and morphology of the margin suggest that the entire continental shelf in the area, coincident with major continental crustal lineaments, was ice-covered during the Last glacial cycle, and transverse troughs delineate the paleo-icestream drainage patterns. A recent investigation of Notre Dame Trough revealed the existence of large sediment failures on the shelf. The current study investigates complex seafloor erosion and widespread mass transport deposition (MTD) on the continental slope seaward of Notre Dame Trough, using recently-acquired high resolution seismic reflection data and piston cores. The new data reveal that a trough mouth fan (TMF) is present on the slope seaward of Notre Dame Trough. The Notre Dame TMF is characterized by a succession of stacked debris flows, but does not show a lobate shape in plan view like other classic TMFs. Instead, the Notre Dame TMF has abruptly-truncated margins suggesting post-depositional failure and erosion of the fan deposits. Seismic reflection data show that the locations of the failures along the TMF margin are coincident with a set of shallow faults; however the current dataset does not image the deeper portion of the faults. On the upper slope immediately south of the TMF, a narrow and deeply incised canyon is located along-trend with the Notre Dame Trough. The location of this canyon appears to be controlled by a fault. Downslope from this canyon, along the southern margin of the TMF, a 25 km wide, flat-floored, U-shaped valley was eroded into a succession of stacked MTD-filled channels. Seismic stratigraphic analysis shows that the valley developed around the same time as the adjacent TMF, however, the valley morphology and evidence for repeated slope failure suggests that the processes responsible for its formation were different than the processes that formed the nearby TMF. Age control provided from piston cores suggest that the last major slope failure that contributed to valley formation probably occurred at ~29 ka. Geotechnical measurements from piston cores show slightly underconsolidated sediments. The results indicate that this part of the margin is more unstable than Orphan Basin and Labrador slope regions. Given the low factor of safety and the complex fault system, low energy earthquake from the surrounding area could be enough to potentially trigger landslides.
Thaw pond dynamics and carbon emissions in a Siberian lowland tundra landscape
NASA Astrophysics Data System (ADS)
van Huissteden, Ko; Heijmans, Monique; Dean, Josh; Meisel, Ove; Goovaerts, Arne; Parmentier, Frans-Jan; Schaepman-Strub, Gabriela; Belelli Marchesini, Luca; Kononov, Alexander; Maximov, Trofim; Borges, Alberto; Bouillon, Steven
2017-04-01
Arctic climate change induces drastic changes in permafrost surface wetness. As a result of thawing ground ice bodies, ice wedge troughs and thaw ponds are formed. Alternatively, ongoing thaw may enhance drainage as a result of increased interconnectedness of thawing ice wedge troughs, as inferred from a model study (Liljedahl et al., 2016, Nature Geoscience, DOI: 10.1038/NGEO2674). However, a recent review highlighted the limited predictability of consequences of thawing permafrost on hydrology (Walvoord and Kurylyk, 2016, Vadose Zone J., DOI:10.2136/vzj2016.01.0010). Overall, these changes in tundra wetness modify carbon cycling in the Arctic and in particular the emissions of CO2 and CH4 to the atmosphere, providing a possibly positive feedback on climate change. Here we present the results of a combined remote sensing, geomorphological, vegetation and biogechemical study of thaw ponds in Arctic Siberian tundra, at Kytalyk research station near Chokurdakh, Indigirka lowlands. The station is located in an area dominated by Pleistocene ice-rich 'yedoma' sediments and drained thaw lake bottoms of Holocene age. The development of three types of ponds in the Kytalyk area (polygon centre ponds, ice wedge troughs and thaw ponds) has been traced with high resolution satellite and aerial imagery. The remote sensing data show net areal expansion of all types of ponds. Next to formation of new ponds, local vegetation change from dry vegetation types to wet, sedge-dominated vegetation is common. Thawing ice wedges and thaw ponds show an increase in area and number at most studied locations. In particular the area of polygon centre ponds increased strongly between 2010 and 2015, but this is highly sensitive to antecedent precipitation conditions. Despite a nearly 60% increase of the area of thawing ice wedge troughs, there is no evidence of decreasing water surfaces by increasing drainage through connected ice wedge troughs. The number of thaw ponds shows an equilibrium between newly formed and disappearing ponds, although their net area increased by 16%. The disappearing of ponds was mostly the result of vegetation succession, rather than drainage. This vegetation succession results from an invasion by sedges, followed by establishment of Sphagnum and seedlings of dwarf shrubs. The formation of thaw ponds and troughs resulting from small-scale permafrost collapse results in a drastic change of CH4 and CO2 emissions, from near-zero emission or uptake to high emission. New water surfaces with drowned dry tundra vegetation show the highest emission. However, rapid vegetation succession may mitigate these emissions over time, in particular in the relatively shallow thaw ponds. In contrast, the polygon centre ponds with a stable, oligotrophic vegetation show modest and constant CH4 emission and CO2 uptake.
Preliminary report, cruises L1-86-NC and L2-86-NC, Escanaba Trough, Gorda Ridge
Morton, J.L.; Normark, W.R.; Ross, Stephanie L.; Koski, R.A.; Holmes, M.L.; Shanks, Wayne C.; Zierenberg, R.A.; Lyle, M.W.; Benninger, L.M.
1987-01-01
Eight large (up to 200 m across) and many small massive sulfide deposits were photographed and sampled at the sediment-covered Escanaba Trough, southern Gorda Ridge, during S.P. Lee cruises L1-86-NC and L2-86-NC in 1986. The deposits are associated with two volcanic edifices within the sedimentary fill along the axis of Escanaba Trough. The sulfide and other hydrothermal minerals are deposited on the seafloor as well as within the sedimentary section. High concentrations of Pb and As in some of the sulfide samples indicates significant interaction between hydrothermal fluids and sediment at depth.
Sedimentation, volcanism, and ancestral lakes in the Valles Marineris: Clues from topography
NASA Technical Reports Server (NTRS)
Lucchitta, B. K.; Isbell, N. K.; Howington-Kraus, A.
1993-01-01
Compilation of a simplified geologic/geomorphic map onto a digital terrain model of Valles Marineris has permitted quantitative evaluations of topographic parameters. The study showed that, if their interior layered deposits are lacustrine, the ancestral Valles Marineris must have consisted of isolated basins. If, on the other hand, the troughs were interconnected as they are today, the deposits are most likely to volcanic origin, and the mesas in the peripheral troughs may be table mountains. The material eroded from the trough walls was probably not sufficient to form all of the interior layered deposits, but it may have contributed significantly to their formation.
Inciarte-Mundo, José; Ramirez, Julio; Hernández, Maria Victoria; Ruiz-Esquide, Virginia; Cuervo, Andrea; Cabrera-Villalba, Sonia Raquel; Pascal, Mariona; Yagüe, Jordi; Cañete, Juan D; Sanmarti, Raimon
2016-07-08
Serum levels of calprotectin, a major S100 leucocyte protein, are associated with disease activity in rheumatoid arthritis (RA) and psoriatic arthritis (PsA) patients. Higher drug trough serum levels are associated with good response in patients treated with tumour necrosis factor inhibitors (TNFi). Power Doppler ultrasound (PDUS) synovitis is predictive of flare and progression of structural damage in patients in clinical remission. The purpose of this study was to analyse the accuracy of calprotectin and TNFi trough serum levels in detecting PDUS synovitis in RA and PsA patients in clinical remission or with low disease activity who were receiving TNFi. We conducted a cross-sectional study of 92 patients (42 with RA, 50 with PsA) receiving adalimumab (ADA), etanercept (ETN) or infliximab who were in remission or had low disease activity (28-joint Disease Activity Score based on erythrocyte sedimentation rate <3.2). Associations of calprotectin, TNFi trough serum levels and acute phase reactants with PDUS synovitis were assessed using correlation and linear regression analyses. The accuracy and discriminatory capacity in detecting PDUS synovitis was assessed using ROC curves. PDUS synovitis was found in 62.4 % of RA patients and 32 % of PsA patients. Both RA and PsA patients with PDUS synovitis had higher calprotectin levels and lower TNFi trough serum levels. Calprotectin positively correlated with ultrasound scores (all r coefficients >0.50 in RA). Calprotectin correlated with the PDUS synovitis score in patients treated with ADA and ETN. Using PDUS synovitis (yes or no) as the reference variable, calprotectin had an AUC of 0.826. The best cut-off was ≥1.66 μg/ml, with a likelihood ratio of 2.77. C-reactive protein (AUC 0.673) and erythrocyte sedimentation rate (AUC 0.731) had a lower discriminatory capacity. TNFi trough serum levels were significantly associated with PDUS synovitis (OR 0.67, 95 % CI 0.52-0.85, p < 0.001) but their accuracy (AUC <0.5) was less than that of calprotectin. TNFi trough serum levels were inversely correlated with calprotectin and PDUS synovitis in RA and PsA patients receiving ADA and ETN. Calprotectin and TNFi trough serum levels may help identify PDUS synovitis in RA and PsA patients in clinical remission or with low disease activity.
Convection and Easterly Wave Structure Observed in the Eastern Pacific Warm-Pool during EPIC-2001
NASA Technical Reports Server (NTRS)
Peterson, Walter A.; Cifelli, R.; Boccippio, D.; Rutledge, S. A.; Fairall, C. W.; Arnold, James E. (Technical Monitor)
2002-01-01
During September-October 2001, the East Pacific Investigation of Climate Processes in the Coupled Ocean-Atmosphere System (EPIC-2001) ITCZ field campaign focused on studies of deep convection in the warm-pool region of the East Pacific. In addition to the TAO mooring array, observational platforms deployed during the field phase included the NOAA ship RN Ronald H. Brown, the NSF ship RN Horizon, and the NOAA P-3 and NCAR C-130 aircraft. This study combines C-band Doppler radar, rawinsonde, and surface heat flux data collected aboard the RN Brown to describe ITCZ convective structure and rainfall statistics in the eastern Pacific as a function of 3-5 day easterly wave phase. Three distinct easterly wave passages occurred during EPIC-2001. Wind and thermodynamic data reveal that the wave trough axes exhibited positively correlated U and V winds and a slight westward phase tilt with height. A relatively strong (weak) northeasterly deep tropospheric shear followed the trough (ridge) axis. Temperature and humidity perturbations exhibited mid-to upper level cooling (warming) and drying (moistening) in the northerly (trough and southerly) phase. At low levels warming (cooling) occurred in the northerly (southerly) phase with little change in the relative humidity, though mixed layer mixing ratios were larger during the northerly phase. When composited, radar, sounding, lightning and surface heat flux observations suggest the following systematic behavior as a function of wave phase: approximately zero to one quarter wavelength ahead of (behind) the wave trough in northerly (southerly) flow, larger (smaller) CAPE, lower (higher) CIN, weaker (stronger) tropospheric shear, higher (lower) conditional mean rain rates, higher (lower) lightning flash densities, and more (less) robust convective vertical structure occurred. Latent and sensible heat fluxes reached a minimum in the northerly phase and then increased through the trough, reaching a peak during the ridge phase (leading the peak in CAPE). From a radar echo coverage perspective, larger areas of light rain and slightly larger (10%) area averaged rain rates occurred in the vicinity of, and just behind, the trough axes in southerly flow. Importantly, the transition in convective structure observed across the trough axis when considered with the relatively small change in area mean rain rates suggests the presence of a transition in the vertical structure of diabatic heating across the easterly waves examined. The inferred transition in heating structure is supported by radar diagnosed divergence profiles that exhibit convective (stratiform) characteristics ahead of (behind) the trough.
Alt, J.C.; Shanks, Wayne C.; Jackson, M.C.
1993-01-01
The sulfur contents and sulfur isotopic compositions of 24 glassy submarine volcanics from the Mariana Island Arc and back-arc Mariana Trough were determined in order to investigate the hypothesis that subducted seawater sulfur (??34S = 21???) is recycled through arc volcanism. Our results for sulfur are similar to those for subaerial arc volcanics: Mariana Arc glasses are enriched in 34S (??34S = up to 10.3???, mean = 3.8???) and depleted in S (20-290 ppm, mean = 100 ppm) relative to MORB (850 ppm S, ??34S = 0.1 ?? 0.5???). The back-arc trough basalts contain 200-930 ppm S and have ??34S values of 1.1 ?? 0.5???, which overlap those for the arc and MORB. The low sulfur contents of the arc and some of the trough glasses are attributed to (1) early loss of small amounts of sulfur through separation of immiscible sulfide and (2) later vapor-melt equilibrium control of sulfur contents and loss of sulfur in a vapor phase from sulfide-undersaturated melts near the minimum in sulfur solubility at f{hook}O2 ??? NNO (nickel-nickel oxide). Although these processes removed sulfur from the melts their effects on the sulfur isotopic compositions of the melts were minimal. Positive trends of ??34S with 87Sr 86Sr, LILE and LREE contents of the arc volcanics are consistent with a metasomatic seawater sulfur component in the depleted sub-arc mantle source. The lack of a 34S-rich slab signature in the trough lavas may be attributed to equilibration of metasomatic fluid with mantle material along the longer pathway from the slab to the source of the trough volcanics. Sulfur is likely to have been transported into the mantle wedge by metasomatic fluid derived from subducted sediments and pore fluids. Gases extracted from vesicles in arc and back-arc samples are predominantly H2O, with minor CO2 and traces of H2S and SO2. CO2 in the arc and back-arc rocks has ??13C values of -2.1 to -13.1???, similar to MORB. These data suggest that degassing of CO2 could explain the slightly lower ??13C values for some Mariana Trough volcanic glasses, and that incorporation of subduction-derived organic carbon into the Mariana Trough mantle source may not be necessary. More analyses are required to resolve this question, however. ?? 1993.
NASA Astrophysics Data System (ADS)
Sawai, Y.; Momohara, A.
2017-12-01
Five episodic submergence events during the past 3500 years were recognized at the Ukishima-ga-hara lowland, northern coast of Suruga Trough (eastern Nankai Trough). Coastal submergence in this region was originally reported by Osamu Fujiwara and his colleagues (e.g., Fujiwara et al., 2016) based mainly on changes in lithostratigraphy from a peaty layer that abruptly changed to a light-colored mud and results of microfossil analyses (pollen and diatoms from 57 and 13 samples, respectively). They attributed the submergence events to coseismic deformation associated with earthquakes in the Fujikawa-kako fault zone or Suruga Trough. Here I reevaluated the micropaleontology of this area using 200 samples from 15 cores to reconstruct the full history of coastal submergence during the last few thousand years. The submergence events were shown not by lithostratigraphy but clearly by changes in fossil diatom assemblages and plant macrofossils. For example, at about 2.3 m and 3.1 m below the ground surface, while aerophilic diatoms (such as Diadesmis contenta and Diploneis elliptica) dominate the underlying peaty layer, freshwater and brackish planktonic taxa (Aulacoseira and Thalassiosira) abound in the overlying layer. As many as five such changes in diatom assemblages were found in a 8-m core and radiocarbon ages constrain the age of the entire sequence to 3500 yr BP.
Reynolds, Richard J.
2007-01-01
The nature and extent of valley-fill aquifers in the Port Jervis Trough was evaluated for a 16 mile section of this valley from the Orange-Sullivan County line near Westbrookville to the village of Napanoch in Ulster County as part of the U.S. Geological Survey's Detailed Aquifer Mapping Program in New York State. The principal aquifer in the Port Jervis Trough is a 50 feet thick outwash aquifer that extends from the Phillipsport Moraine near Summitville, southward through the study area to Port Jervis, N.Y. Previous studies had estimated as much as 500 feet of saturated drift in parts of the Trough, but new well data show that much of the valley fill consists of fine-grained lacustrine sediments. Drillers' logs show that the outwash aquifer south of Summitville is underlain by as much as 275 feet of lacustrine silt and clay. North of the Phillipsport Moraine, three large glaciolacustrine deltas that were built into Glacial Lake Wawarsing provide some local and discontinuous confined aquifers through their coarser bottomset beds. Elsewhere in the Trough, collapsed and buried portions of kame deltas and terraces provide local confined aquifers. The outwash aquifer appears to be very transmissive, as evidenced by the high specific capacity of 130 gallons per minute per foot [(gal/min)/ft] of a commercial test well screened in the aquifer.
NASA Astrophysics Data System (ADS)
Bai, Yefei; Yamazaki, Yoshiki; Cheung, Kwok Fai
2018-04-01
The latest tsunami evacuation maps of Hawaii include an extreme scenario triggered by an Mw 9.3 Aleutian earthquake with large near-trench rupture. The tectonic plate motion produces concentrated seafloor uplift toward the deepest part of the trench generating a tsunami with strong non-hydrostatic characters. A parametric study shows the skewed seafloor uplift produces a dispersive leading crest followed by a prominent trough in the form of an N-wave. The trough maintains its depth across the ocean in the absence of side lobes and dispersion. Shifting of the uplift toward the trench tends to deepen the trough, but has diminishing effects on the wave crest away from the source. While the attenuated leading crest produces relatively moderate runup on north-facing shores of the Hawaiian Islands, with matching of the N-wave and shelf resonance periods, the trough produces an impulsive drawdown followed by an energetic upswing with unprecedented runup for a far-field tsunami. A set of control computations without dispersion reaffirms that a non-hydrostatic model is essential to account for these complex wave processes from the source to the shore. This case study highlights the unique tsunami hazards posed by the Aleutians to Hawaii and the role of wave troughs in delineating the impacts for hazard assessment and engineering design.
A Low-Power and Portable Biomedical Device for Respiratory Monitoring with a Stable Power Source
Yang, Jiachen; Chen, Bobo; Zhou, Jianxiong; Lv, Zhihan
2015-01-01
Continuous respiratory monitoring is an important tool for clinical monitoring. Associated with the development of biomedical technology, it has become more and more important, especially in the measuring of gas flow and CO2 concentration, which can reflect the status of the patient. In this paper, a new type of biomedical device is presented, which uses low-power sensors with a piezoresistive silicon differential pressure sensor to measure gas flow and with a pyroelectric sensor to measure CO2 concentration simultaneously. For the portability of the biomedical device, the sensors and low-power measurement circuits are integrated together, and the airway tube also needs to be miniaturized. Circuits are designed to ensure the stability of the power source and to filter out the existing noise. Modulation technology is used to eliminate the fluctuations at the trough of the waveform of the CO2 concentration signal. Statistical analysis with the coefficient of variation was performed to find out the optimal driving voltage of the pressure transducer. Through targeted experiments, the biomedical device showed a high accuracy, with a measuring precision of 0.23 mmHg, and it worked continuously and stably, thus realizing the real-time monitoring of the status of patients. PMID:26270665
NASA Astrophysics Data System (ADS)
Rebesco, M.; Liu, Y.; Camerlenghi, A.; Winsborrow, M. C.; Laberg, J.; Caburlotto, A.; Diviacco, P.; Accettella, D.; Sauli, C.; Wardell, N.
2010-12-01
IPY Activity N. 367 focusing on Neogene ice streams and sedimentary processes on high- latitude continental margins (NICE-STREAMS) resulted in two coordinated cruises on the adjacent Storfjorden and Kveithola trough-mouth fans in the NW Barents Sea: SVAIS Cruise of BIO Hespérides, summer 2007, and EGLACOM Cruise of Cruise R/V OGS-Explora, summer 2008. The objectives were to acquire a high-resolution set of bathymetric, seismic and sediment core data in order to decipher the Neogene architectural development of the glacially-dominated NW Barents Sea continental margin in response to natural climate change. The paleo-ice streams drained ice from southern Spitsbergen, Spitsbergen Bank, and Bear Island. The short distance from the ice source to the calving front produced a short residence time of ice, and therefore a rapid response to climatic changes. We describe here the EGLACOM data collected within the Kveithola Trough, an E-W trending glacial trough in the NW Barents Sea, NW of the Bear Island. Swath bathymetry shows that the seafloor is characterised by E-W trending mega-scale glacial lineations (MSGL) that record a fast flowing ice stream draining the Svalbard/Barents Sea Ice Sheet (SBIS) during the Last Glacial Maximum (LGM). MSGL are overprinted by transverse sediment ridges about 15 km apart which give rise to a staircase axial profile of the trough. Such transverse ridges are interpreted as grounding-zone wedges (GZW) formed by deposition of unconsolidated, saturated subglacial till during episodic ice stream retreat. Sub-bottom (CHIRP) and multi-channel reflection seismic data show that present-day morphology is largely inherited from the palaeo-seafloor topography at the time of deposition of the transverse ridges, overlain by a draping glaciomarine unit up to over 15 m thick. Our data allow the reconstruction of depositional processes that accompanied the deglaciation of the Spitsbergen Bank area. The sedimentary drape deposited on top of the GZWs which accumulated at a very high rate in the order of 1-1.5 m ka-1 has a potential to preserve a high resolution palaeoclimatic record of the deglaciation and post-glacial condition in this sector of the Barents Sea.
Seismic stratigraphic architecture of the Disko Bay trough-mouth fan system, West Greenland
NASA Astrophysics Data System (ADS)
Hofmann, Julia C.; Knutz, Paul C.
2015-04-01
Spatial and temporal changes of the Greenland Ice Sheet on the continental shelf bordering Baffin Bay remain poorly constrained. Then as now, fast-flowing ice streams and outlet glaciers have played a key role for the mass balance and stability of polar ice sheets. Despite their significance for Greenland Ice Sheet dynamics and evolution, our understanding of their long-term behaviour is limited. The central West Greenland margin is characterized by a broad continental shelf where a series of troughs extend from fjords to the shelf margin, acting as focal points for trough-mouth fan (TMF) accummulations. The sea-ward bulging morphology and abrupt shelf-break of these major depositional systems is generated by prograding depocentres that formed during glacial maxima when ice streams reached the shelf edge, delivering large amounts of subglacial sediment onto the continental slope (Ó Cofaigh et al., 2013). The aim of this study is to unravel the seismic stratigraphic architecture and depositional processes of the Disko Bay TMF, aerially the largest single sedimentary system in West Greenland, using 2D and 3D seismic reflection data, seabed bathymetry and stratigraphic information from exploration well Hellefisk-1. The south-west Disko Bay is intersected by a deep, narrow trough, Egedesminde Dyb, which extends towards the southwest and links to the shallower and broader cross-shelf Disko Trough (maximum water depths of > 1000 m and a trough length of c. 370 km). Another trough-like depression (trough length of c. 120 km) in the northern part of the TMF, indicating a previous position of the ice stream, can be distinguished on the seabed topographic map and the seismic images. The Disko Bay TMF itself extends from the shelf edge down to the abyssal plain (abyssal floor depths of 2000 m) of the southern Baffin Bay. Based on seismic stratigraphic configurations relating to reflection terminations, erosive patterns and seismic facies (Mitchum et al., 1977), the TMF succession has been divided into five seismic units, each representing different stages in the progradational accumulation of the TMF system. This poster and ongoing study will discuss how the ice-stream flow switching is linked to changes in depocentres of sedimentary sequences and further investigate the major controls, e.g. ice-sheet dynamics, ocean-climate changes, tectonic forcing and subglacial geology, that determined the evolution of the Disko Bay TMF. Essencial bibliography Mitchum, R.M. Jr., Vail, P.R., Sangree, J.B., 1977. Seismic stratigraphy and global changes of sea level, Part 6: Stratigraphic interpretation of seismic reflection patterns in depositional sequences. AAPG Memoir 26, 117-133. Ó Cofaigh, C., Andrews, J.T., Jennings, A.E., Dowdeswell, J.A., Hogan, K.A., Kilfeather, A.A., Sheldon, C., 2013. Glacimarine lithofacies, provenance and depositional processes on a West Greenland trough-mouth fan. Journal of Quaternary Science, 28(1), 13-26.
NASA Astrophysics Data System (ADS)
Skurikhin, A. N.; Gangodagamage, C.; Rowland, J. C.; Wilson, C. J.
2013-12-01
Arctic lowland landscapes underlain by permafrost are often characterized by polygon-like patterns such as ice-wedge polygons outlined by networks of ice wedges and complemented with polygon rims, troughs, shallow ponds and thermokarst lakes. Polygonal patterns and corresponding features are relatively easy to recognize in high spatial resolution satellite imagery by a human, but their automated recognition is challenging due to the variability in their spectral appearance, the irregularity of individual trough spacing and orientation within the patterns, and a lack of unique spectral response attributable to troughs with widths commonly between 1 m and 2 m. Accurate identification of fine scale elements of ice-wedge polygonal tundra is important as their imprecise recognition may bias estimates of water, heat and carbon fluxes in large-scale climate models. Our focus is on the problem of identification of Arctic polygonal tundra fine-scale landscape elements (as small as 1 m - 2 m width). The challenge of the considered problem is that while large water bodies (e.g. lakes and rivers) can be recognized based on spectral response, reliable recognition of troughs is more difficult. Troughs do not have unique spectral signature, their appearance is noisy (edges are not strong), their width is small, and they often form connected networks with ponds and lakes, and thus they have overlapping spectral response with other water bodies and surrounding non-water bodies. We present a semi-automated approach to identify and classify Arctic polygonal tundra landscape components across the range of spatial scales, such as troughs, ponds, river- and lake-like objects, using high spatial resolution satellite imagery. The novelty of the approach lies in: (1) the combined use of segmentation and shape-based classification to identify a broad range of water bodies, including troughs, and (2) the use of high-resolution WorldView-2 satellite imagery (with resolution of 0.6 m) for this identification. The approach starts by segmenting water bodies from an image, which are then categorized using shape-based classification. Segmentation uses combination of pan sharpened multispectral bands and is based on the active contours without edges technique. The segmentation is robust to noise and can detect objects with weak boundaries that is important for extraction of troughs. We then categorize the segmented regions via shape based classification. Because segmentation accuracy is the main factor impacting the quality of the shape-based classification, for segmentation accuracy assessment we created reference image using WorldView-2 satellite image of ice-wedge polygonal tundra. Reference image contained manually labelled image regions which cover components of drainage networks, such as troughs, ponds, rivers and lakes. The evaluation has shown that the approach provides a good accuracy of segmentation and reasonable classification results. The overall accuracy of the segmentation is approximately 95%, the segmentation user's and producer's accuracies are approximately 92% and 97% respectively.
NASA Astrophysics Data System (ADS)
Rebesco, Michele; Liu, Yanguang; Camerlenghi, Angelo; Winsborrow, Monica; Sverre Laberg, Jan; Caburlotto, Andrea; Diviacco, Paolo; Accettella, Daniela; Sauli, Chiara; Wardell, Nigel
2010-05-01
Kveithola Trough, an E-W trending cross-shelf glacial trough in the NW Barents Sea, was surveyed for the first time during the EGLACOM cruise between 8th July and 4th August 2008 on board R/V OGS-Explora. EGLACOM (Evolution of a GLacial Arctic COntinental Margin: the southern Svalbard ice stream-dominated sedimentary system) project is the Italian contribution to the International Polar Year (IPY) Activity 367 (Neogene ice streams and sedimentary processes on high- latitude continental margins - NICE STREAMS). Such IPY activity included as well the Spanish SVAIS 2008 cruise on board BIO Hesperides. EGLACOM data acquisition, focused on the Storfjorden Fan and Kveithola Trough, included a multi-channel seismic (MCS) reflection survey and the simultaneous collection of swath bathymetry and sub-bottom CHIRP profiles. Swath bathymetry in the Kveithola Trough shows that the seafloor is characterized by E-W trending mega-scale glacial lineations (MSGL). These include large-scale ridges about 2 km wide and 15 m high as well as smaller grooves about 100 m wide and a few metres deep. Such MSGL record the fast flow of an ice stream draining the Svalbard/Barents Sea Ice Sheet (SBSIS) during the Last Glacial Maximum (LGM). MSGL are overprinted by transverse sediment ridges about 15 km apart which give rise to a staircase long profile of the trough. Such transverse ridges are interpreted as grounding-zone wedges (GZW) formed by deposition of unconsolidated, saturated subglacial till during ice stream retreat. Sub-bottom (CHIRP) and multi-channel reflection seismic data show that the morphology is controlled by stacked sets of lensoidal transparent units (tills) overlain by a draping glaciomarine unit up to over 15 m thick. Formed during temporary stillstands in grounding-zone position before complete deglaciation, GZW ridges are diagnostic of episodic retreat. Our data allow the reconstruction of deglaciation in the Spitsbergen Bank area, with each stage during deglaciation recorded by deposition of a GZW. Three independent lines of reasoning suggest that an ice cap persisted on Spitsbergen Bank for some thousand years and lasted much longer than those that fed the adjacent glacial troughs: 1) the freshness of the morphology in Kveithola Trough compared to that of adjacent Storfjorden and Bear Island troughs; 2) the volume of sediment in the GZW ridges compared to the small catchment area; 3) preliminary assessment of the stratigraphic position of debris flow deposits on the continental slope. The 15 m of sedimentary drape deposited on top of GZW ridges contains a high-resolution palaeoclimatic record of the last thousand years, which accumulated at a very high average sedimentation rate. Sampling (through drilling) of the thin glaciomarine sediments between the till lenses of the successive GZW ridges may allow the dating of deglaciation phases in the Barents Sea.
Aerial mulching techniques-trough fire
Robert Faust
2008-01-01
The Trough fire occurred in August 2001 on the Mendocino National Forest of northern California. A burned area emergency rehabilitation team evaluated the fire effects on the watershed. Concerns were soil from the denuded slopes moving into streams affecting fishery values, reservoir sedimentation and storm runoff plugging culverts leading to road wash outs. Past...
Strawberry Production in Soilless Substrate Troughs – Plant Growth
USDA-ARS?s Scientific Manuscript database
Soilless substrates made of peat moss, coconut coir, perlite, rockwool or bark are pathogen free and they have been used in strawberry production in Europe in troughs or containers. Open field strawberry production in soilless substrate is new to California growers. The objective of this study was t...
OUT Success Stories: Solar Trough Power Plants
DOE R&D Accomplishments Database
Jones, J.
2000-08-01
The Solar Electric Generating System (SEGS) plants use parabolic-trough solar collectors to capture the sun's energy and convert it to heat. The SEGS plants range in capacity from 13.8 to 80 MW, and they were constructed to meet Southern California Edison Company's periods of peak power demand.
Prefabricated microvascular autograft in tracheal reconstruction.
Fayad, J; Kuriloff, D B
1994-10-01
Tracheal reconstruction continues to be a challenge in head and neck surgery. Numerous techniques, including the use of alloplasts, composite grafts, and staged laryngotracheal troughs, have met with limited success because of implant exposure, infection, persistent granulation tissue, and eventual restenosis. With recently introduced techniques for soft-tissue molding, bone induction with bone morphogenetic protein, and microvascular free tissue transfer, a rodent model was developed to create a well-vascularized tracheal autograft. In this model, a rigid tube having the same dimensions and flexibility as the native trachea was created by wrapping a cylindrical silicone tracheal mold with a layer of vascularized adductor thigh muscle pedicled on the femoral vessels in the groin. Tracheal rings were created by filing transverse troughs in the muscle bed with bone morphogenetic protein-primed demineralized bone matrix before wrapping around the silicone mold. Grafts harvested at 2 weeks demonstrated rigid skeletal support provided by heterotopic bone formation in the form of rings and a smooth inner lining produced by fibroplasia. Bone transformation was controlled and restricted to the muscle troughs, allowing intervening regions of soft tissue and thus producing a flexible neotrachia. With this model, a homologous, vascularized tracheal autograft capable of microvascular free tissue transfer was fabricated based on the femoral vessels. Prefabrication of composite grafts, through the use of soft-tissue molding, bone induction, and subsequent free tissue transfer, has an unlimited potential for use in head and neck reconstruction.
NASA Astrophysics Data System (ADS)
Jolliff, J.; Jarosz, E.; Penko, A.; Smith, T.
2017-12-01
The "Lafourche Trough" is a mud/silt -dominated, elongate seafloor depression located between transgressive sandy shoals approximately 50 km south of Cocodrie, Louisiana. These irregular bathymetric features are relicts of the abandoned Lafourche delta complex that still have an impact upon coupled sediment-hydrodynamic processes occurring today. Repeated optical and physical oceanographic surveys conducted during the spring of 2015 and winter 2017 reveal persistent bottom nepheloid layers (BNLs) characterized by extreme optical turbidity (beam attenuation 10 m-1, 532 nm). The manifestation and persistence of cohesive sediment BNLs in this area appears to result from a complex interplay between tidal currents, bathymetry, and frontal dynamics along the edge of the Mississippi River plume. Numerical experiments were performed using the Coupled Ocean Atmosphere Mesoscale Prediction System (COAMPS), an integrated air-sea-wave operational forecasting tool, that includes a simplified numerical sediment resuspension and transport scheme in order to simulate the nepheloid layer observations through the trough. The model results suggest that the wave-current bottom boundary layer is a critical factor in BNL development, and thusly, without wave model integration into COAMPS the system struggles to replicate the observations. Future modeling work will need to explore the potential suppression of physical mixing due to density perturbations along the BNL to fluid mud continuum within the bottom boundary layer.
Trained Inquiry Skills on Heat and Temperature Concepts
NASA Astrophysics Data System (ADS)
Hasanah, U.; Hamidah, I.; Utari, S.
2017-09-01
Inquiry skills are skills that aperson needs in developing concepts, but the results of the study suggest that these skills haven’t yet been trained along with the development of concepts in science feeding, found the difficulties of students in building the concept scientifically. Therefore, this study aims to find ways that are effective in training inquiry skills trough Levels of Inquiry (LoI) learning. Experimental research with one group pretest-postest design, using non-random sampling samples in one of vocational high school in Cimahi obtained purposively 33 students of X class. The research using the inquiry skills test instrument in the form of 15questions multiple choice with reliability in very high category. The result of data processing by using the normalized gain value obtained an illustration that the ways developed in the LoI are considered effective trained inquiry skills in the middle category. Some of the ways LoI learning are considered effective in communicating aspects through discovery learning, predicting trough interactive demonstration, hypotheses through inquiry lesson, and interpreting data through inquiry lab, but the implementation of LoI learning in this study hasn’t found a way that is seen as effective for trespassing aspects of designing an experiment.
Tanzi, Maria G; Undre, Nasrullah; Keirns, James; Fitzsimmons, William E; Brown, Malcolm; First, M Roy
2016-08-01
Prolonged-release tacrolimus was developed as a once-daily formulation with ethylcellulose as the excipient, resulting in slower release and reduction in peak concentration (Cmax ) for a given dose compared with immediate-release tacrolimus, which is administered twice daily. This manuscript reviews pharmacokinetic information on prolonged-release tacrolimus in healthy subjects, in transplant recipients converted from immediate-release tacrolimus, and in de novo kidney and liver transplant recipients. As with the immediate-release formulation, prolonged-release tacrolimus shows a strong correlation between trough concentration (Cmin ) and area under the 24-hour time-concentration curve (AUC24 ), indicating that trough whole blood concentrations provide an accurate measure of drug exposure. We present the pharmacokinetic similarities and differences between the two formulations, so that prescribing physicians will have a better understanding of therapeutic drug monitoring in patients receiving prolonged-release tacrolimus. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Edstein, Michael D; Kocisko, David A; Walsh, Douglas S; Eamsila, Chirapa; Charles, Bruce G; Rieckmann, Karl H
2003-12-15
We measured plasma tafenoquine concentrations in Thai soldiers given a monthly regimen of tafenoquine to determine whether these concentrations adequately suppressed malarial infections on the Thai-Cambodian border. After receiving a treatment course of artesunate and doxycycline, 104 male soldiers were administered a loading dose of tafenoquine (400 mg daily for 3 days), followed by tafenoquine monthly (400 mg every 4 weeks) for 5 months. Consecutive monthly mean (+/- standard deviation) trough plasma tafenoquine concentrations were 223+/-41, 127+/-29, 157+/-51, 120+/-24, and 88+/-20 ng/mL. Only 1 soldier developed malaria during the study. At the time of malaria diagnosis, his plasma tafenoquine concentration was 40 ng/mL, which was approximately 3-fold lower than the trough concentrations of the other soldiers. Although low tafenoquine concentrations appear to be uncommon, additional investigations are needed to determine the relationship between plasma tafenoquine concentrations and suppression of malaria.
Medlin, John B.
1976-05-25
A charging machine for loading fuel slugs into the process tubes of a nuclear reactor includes a tubular housing connected to the process tube, a charging trough connected to the other end of the tubular housing, a device for loading the charging trough with a group of fuel slugs, means for equalizing the coolant pressure in the charging trough with the pressure in the process tubes, means for pushing the group of fuel slugs into the process tube and a latch and a seal engaging the last object in the group of fuel slugs to prevent the fuel slugs from being ejected from the process tube when the pusher is removed and to prevent pressure liquid from entering the charging machine.
Peak Measurement for Vancomycin AUC Estimation in Obese Adults Improves Precision and Lowers Bias.
Pai, Manjunath P; Hong, Joseph; Krop, Lynne
2017-04-01
Vancomycin area under the curve (AUC) estimates may be skewed in obese adults due to weight-dependent pharmacokinetic parameters. We demonstrate that peak and trough measurements reduce bias and improve the precision of vancomycin AUC estimates in obese adults ( n = 75) and validate this in an independent cohort ( n = 31). The precision and mean percent bias of Bayesian vancomycin AUC estimates are comparable between covariate-dependent ( R 2 = 0.774, 3.55%) and covariate-independent ( R 2 = 0.804, 3.28%) models when peaks and troughs are measured but not when measurements are restricted to troughs only ( R 2 = 0.557, 15.5%). Copyright © 2017 American Society for Microbiology.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gdalevich, G.L.; Afonin, V.V.; Eliseev, A.Y.
1986-07-01
Data from the Kosmos-900 satellite are used to examine variations of the ion concentration in the region of the main ionospheric trough at altitudes of about 500 km during the storm of December 18-19, 1978. These variations of ion densities are compared with the variations of the parameters of the interplanetary medium, in particular, with the E /sub y/ = -VB /sub z/ component of the interplanetary electric field. The results of the comparison are discussed. A scheme is proposed for the formation and motion of the trough during magnetic disturbances.
NASA Astrophysics Data System (ADS)
Escutia, C.; Maldonado, A.
1992-03-01
Sparker (3000 J and 8000 J) and multichannel seismic reflection profiles across the Valencia trough show a Messinian unconformity incised by numerous valleys. The main feature of this surface is a large valley that generally underlies the present Valencia valley and is deeply entrenched into the Miocene deposits. The size of this palaeo-valley ranges from 0.5 km wide and 15-100 m deep at its western end, to 1.6-2.8 km wide and 200-250 m deep downstream. An important tributary system is observed, with a main canyon (6-8 km wide and 150-200 m deep) draining the Ebro margin, as well as many other smaller valleys draining the Catalan and Balearic margins. Downstream, other tributaries underlie the present canyons of the Catalan margin. The location of the tributary system is controlled by the Early Miocene rift structures. The relief of the Messinian surface is affected by post-Miocene deformation that results from salt diapirism, extensional faulting and related volcanism. Late Neogene to Quaternary volcanic edifices cut the Messinian surface and coincide with large residual magnetic anomalies. Lower Pliocene to Quaternary salt diapirism in the abyssal plain north of Menorca has created a series of structural highs. Between these highs are deep interdiapiric troughs or basins that have become sediment depocentres during the Plio-Quaternary. The complex network of erosional valleys from the Valencia trough continental margin demonstrates that the valley system in the basin was not related to the refilling of the Mediterranean, but to the Iberian and Balearic margin palaeodrainage that developed during the Messinian desiccation. The presence of at least three erosional unconformities suggests that there were alternating periods of flooding and retreat of Atlantic water during Messinian time. The Messinian subaerial margin with erosional valleys contrasts sharply with the Pliocene-Quaternary marine margin with progradational turbidite systems.
Caffeine Citrate Dosing Adjustments to Assure Stable Caffeine Concentrations in Preterm Neonates.
Koch, Gilbert; Datta, Alexandre N; Jost, Kerstin; Schulzke, Sven M; van den Anker, John; Pfister, Marc
2017-12-01
To identify dosing strategies that will assure stable caffeine concentrations in preterm neonates despite changing caffeine clearance during the first 8 weeks of life. A 3-step simulation approach was used to compute caffeine doses that would achieve stable caffeine concentrations in the first 8 weeks after birth: (1) a mathematical weight change model was developed based on published weight distribution data; (2) a pharmacokinetic model was developed based on published models that accounts for individual body weight, postnatal, and gestational age on caffeine clearance and volume of distribution; and (3) caffeine concentrations were simulated for different dosing regimens. A standard dosing regimen of caffeine citrate (using a 20 mg/kg loading dose and 5 mg/kg/day maintenance dose) is associated with a maximal trough caffeine concentration of 15 mg/L after 1 week of treatment. However, trough concentrations subsequently exhibit a clinically relevant decrease because of increasing clearance. Model-based simulations indicate that an adjusted maintenance dose of 6 mg/kg/day in the second week, 7 mg/kg/day in the third to fourth week and 8 mg/kg/day in the fifth to eighth week assures stable caffeine concentrations with a target trough concentration of 15 mg/L. To assure stable caffeine concentrations during the first 8 weeks of life, the caffeine citrate maintenance dose needs to be increased by 1 mg/kg every 1-2 weeks. These simple adjustments are expected to maintain exposure to stable caffeine concentrations throughout this important developmental period and might enhance both the short- and long-term beneficial effects of caffeine treatment. Copyright © 2017 Elsevier Inc. All rights reserved.
A numerical study on the evolution of the wind-driven circulation in the Yellow Sea in winter
NASA Astrophysics Data System (ADS)
Tak, Y. J.; Cho, Y. K.
2016-02-01
The Yellow Sea is a semi-enclosed marginal sea and its circulation in winter is affected by the winter monsoon. In previous studies, it was found that the circulation of the Yellow Sea in winter consists of downwind and upwind currents. Downwind currents consisting of the Korean Coast Current (KCC) and the Chinese Coast Current (CCC) flow along the boundary of the Yellow Sea, whereas an upwind current consisting of the Yellow Sea Warm Current (YSWC) flows along the central trough of the Yellow Sea. Although some characteristics of such currents and the driving forces of the circulation have been studied by many scientists, the evolution of these currents has received little attention. So, the wind-driven circulation in the Yellow Sea was simulated to explain the changing pattern of these currents in winter and their evolutions were explored by the time-lagged correlation for winter season. According to the lagged correlation, downwind currents occurred in surface layer without a time lag. These downwind currents were more sensitive in the Chinese coast than that in the Korean coast. There is one day time-lag between the wind and the upwind flow developing in the Yellow Sea trough. The YSWC was shifted to the west of the trough after two days and then the KCC strengthened at the same time. It implied the westward shift of the YSWC and the clockwise circulation is developed, two days after the wind blows. The clockwise circulation was one of the reasons that the KCC was stronger than the CCC although the CCC was more sensitive to the wind than the KCC. The clockwise circulation also made the YSWC stronger in the inner YS than it at the entrance of the YS.
Numerical prediction of the Mid-Atlantic states cyclone of 18-19 February 1979
NASA Technical Reports Server (NTRS)
Atlas, R.; Rosenberg, R.
1982-01-01
A series of forecast experiments was conducted to assess the accuracy of the GLAS model, and to determine the importance of large scale dynamical processes and diabatic heating to the cyclogenesis. The GLAS model correctly predicted intense coastal cyclogenesis and heavy precipitation. Repeated without surface heat and moisture fluxes, the model failed to predict any cyclone development. An extended range forecast, a forecast from the NMC analysis interpolated to the GLAS grid, and a forecast from the GLAS analysis with the surface moisture flux excluded predicted weak coastal low development. Diabatic heating resulting from oceanic fluxes significantly contributed to the generation of low level cyclonic vorticity and the intensification and slow rate of movement of an upper level ridge over the western Atlantic. As an upper level short wave trough approached this ridge, diabatic heating associated with the release of latent heat intensified, and the gradient of vorticity, vorticity advection and upper level divergence in advance of the trough were greatly increased, providing strong large scale forcing for the surface cyclogenesis.
Sirolimus Pharmacokinetics in Early Postmyeloablative Pediatric Blood and Marrow Transplantation
Goyal, Rakesh K.; Han, Kelong; Wall, Donna A.; Pulsipher, Michael A.; Bunin, Nancy; Grupp, Stephan A.; Mada, Sripal R.; Venkataramanan, Raman
2014-01-01
This study examined the pharmacokinetics of sirolimus in pediatric allogeneic blood and marrow transplantation (BMT) recipients in the presence and absence of concomitant fluconazole. Forty pediatric BMT recipients received a daily oral dose of sirolimus and a continuous i.v. infusion of tacrolimus for graft-versus-host disease prophylaxis. Fluconazole was administered i.v. to 19 patients and orally to 6 patients. Full pharmacokinetic profiles of sirolimus within a single dosing interval were collected. Whole-blood sirolimus concentrations were measured by HPLC/mass spectrometry. Noncompartmental analysis was performed using WinNonlin. Nonlinear mixed-effects pharmacokinetic models were developed using NONMEM following standard procedures. The mean ± SD sirolimus trough level before the dose (C0) was 8.0 ± 4.6 ng/mL (range, 1.8–21.6 ng/mL). The peak concentration was 19.9 ± 11.8 ng/mL (range, 3.9–46.1 ng/mL), and the trough level 24 hours later (C24) was 9.1 ± 5.3 ng/mL (range, 1.0–19.1 ng/mL). The terminal disposition half-life (T1/2) was 24.5 ± 11.2 hours (range, 5.8–53.2 hours), and the area under the concentration-versus-time curve (AUC0–24) was 401.1 ± 316.3 ng·h/mL (range, 20.7–1332.3 ng·h/mL). In patients at steady state, C0 and C24 were closely correlated (R2 = 0.77) with a slope of 0.99, indicating the achievement of steady state. C24 was 1.7-fold greater (P = .036) and AUC0–24 was 2-fold greater (P = .012) in Caucasian patients (n = 22) compared with Hispanic patients (n = 9). The average apparent oral clearance was 3-fold greater (P = .001) and the apparent oral volume of distribution was 2-fold greater (P = .018) in patients age ≤12 years compared with those age >12 years. C24 was significantly lower in patients (n = 10) who developed grade III–IV aGVHD (n = 10) than in those with grade 0-II aGVHD (n = 22) (6.1 ± 2.9 ng/mL versus 9.4 ± 5.5 ng/mL; P = .044). Dose-normalized sirolimus trough concentrations were significantly higher in patients receiving concomitant fluconazole therapy compared with those not receiving fluconazole (C0: 3.9 ± 2.5 versus 2.4 ± 1.5 ng/mL/mg, P = .030; C24: 4.8 ± 3.3 versus 2.5 ± 1.7 ng/mL/mg, P = .018). This pharmacokinetic study of sirolimus in pediatric patients documents a large interindividual variability in the exposure of sirolimus. Steady-state trough blood concentrations were correlated with drug exposure. Trough concentrations were higher with a concomitant use of fluconazole and were higher in Caucasian patients than in Hispanic patients. Oral clearance was greater in children age ≤12 years than in older children and adolescents. With therapeutic drug monitoring, the majority (79%) of sirolimus trough levels could be maintained within the target range (3–12 ng/mL). This study provides a rationale and support for dose adjustments of sirolimus based on steady-state blood concentrations aimed at achieving a target concentration to minimize toxicity and maximize therapeutic benefits in pediatric BMT recipients. PMID:23266742
Jianwei Zhang; William W. Oliver; Matt D. Busse
2006-01-01
Effects of stand density and shrub competition on growth and development were compared across a gradient of study sites. Challenge, the most productive site, is located in the foothills of the Sierra Nevada, northern California. Pringle Falls is of intermediate productivity in the rain shadow of the central Oregon Cascades. Trough Springs Ridge is the poorest site...
NASA Technical Reports Server (NTRS)
Uccellini, L. W.
1986-01-01
An analysis of the QE II storm of September 9-11, 1978 presents evidence for the existence of upper-level baroclinic processes upstream of the rapidly developing cyclone. The analysis shows that a deepening shortwave trough was located 400 to 500 km upstream of the site of the storm 12 h prior to rapid cyclogenesis. The trough was associated with: (1) a polar jet marked by 65 m/s winds in its core and significant vertical and horizontal wind shear, (2) positive vorticity advection and divergence at the 300 mb level, and (3) an intense frontal zone that extended from 300 mb down to the surface. It also appears that a tropopause fold likely extruded stratospheric air down to the 700-800 mb level, 400-500 km upstream of the surface low and 12 h prior to the explosive development phase of the cyclone. These findings raise questions about Gyakum's (1983) assertion that the QE II storm developed in an area in which the baroclinic support was confined to the lower troposphere and the related assertion by Anthes et al. (1983) that upper-level forcing upstream of the area of rapid cyclogenesis was weak and apparently not important in this case.
NREL, SPI Solar and Trimark Optimize Parabolic Trough Receiver Performance
(CSP) plants. Photo of parabolic trough receiver equipment in a laboratory Photo by Dennis Schroeder Receivers in CSP plants take a lot of abuse, from dramatic temperature changes to numerous mechanical conditions can lead to big improvements in the overall efficiency of CSP plants
USDA-ARS?s Scientific Manuscript database
There are a number of approaches for producing strawberry fruit on a commercial scale without fumigants. One possible approach is to grow strawberries using raised-bed troughs filled with non soil based substrate media. Field trials were conducted using peat, perlite, coir, rice hull, and a redwoo...
Small mammals in oak woodlands in the Puget Trough, Washington.
S.M. Wilson; A.B. Carey
2001-01-01
We surveyed the 22 largest sites dominated by Oregon white oaks on the Fort Lewis Military Reservation, Washington, to determine small-mammal community structure and population abundances. Study areas were in the Puget Trough physiographic province and western hemlock vegetation zone. Most oak communities were ecotonal between prairie and Douglas-fir forest. Small...
Concentrating Solar Power Projects - Delingha 50MW Thermal Oil Parabolic
Trough project | Concentrating Solar Power | NREL Delingha 50MW Thermal Oil Parabolic Trough project Status Date: April 17, 2017 Project Overview Project Name: Delingha 50MW Thermal Oil Parabolic Contractor: IDOM : Thermal energy storage system engineering Plant Configuration Solar Field # of Loops: 190
Concentrating Solar Power Projects - Rayspower Yumen 50MW Thermal Oil
Trough project | Concentrating Solar Power | NREL Rayspower Yumen 50MW Thermal Oil Trough project Status Date: January 31, 2017 Project Overview Project Name: Rayspower Yumen 50MW Thermal Oil . Plant Configuration Solar Field Heat-Transfer Fluid Type: Thermal oil Power Block Turbine Capacity
SOUTHERN ROCKIES... A BROAD LONG WAVE TROUGH CROSSES THE CENTRAL AND SOUTHERN ROCKIES DURING DAY 1...BEFORE WEAKENING AND EXITING INTO THE PLAINS DURING DAY 2. SURFACE LOW PRESSURE FORMING IN RESPONSE TO THE MID MOST RECENT WPC QPF. DAY 1... LIFT ASSOCIATED WITH A BROAD POSITIVELY TILTED LONG WAVE TROUGH MOVING
SeaMARC II mapping of transform faults in the Cayman Trough, Caribbean Sea
Rosencrantz, Eric; Mann, Paul
1992-01-01
SeaMARC II maps of the southern wall of the Cayman Trough between Honduras and Jamaica show zones of continuous, well-defined fault lineaments adjacent and parallel to the wall, both to the east and west of the Cayman spreading axis. These lineaments mark the present, active traces of transform faults which intersect the southern end of the spreading axis at a triple junction. The Swan Islands transform fault to the west is dominated by two major lineaments that overlap with right-stepping sense across a large push-up ridge beneath the Swan Islands. The fault zone to the east of the axis, named the Walton fault, is more complex, containing multiple fault strands and a large pull-apart structure. The Walton fault links the spreading axis to Jamaican and Hispaniolan strike-slip faults, and it defines the southern boundary of a microplate composed of the eastern Cayman Trough and western Hispaniola. The presence of this microplate raises questions about the veracity of Caribbean plate velocities based primarily on Cayman Trough opening rates.
Ionospheric and magnetospheric plasmapauses'
NASA Technical Reports Server (NTRS)
Grebowsky, J. M.; Hoffman, J. H.; Maynard, N. C.
1977-01-01
During August 1972, Explorer 45 orbiting near the equatorial plane with an apogee of about 5.2 R sub e traversed magnetic field lines in close proximity to those simultaneously traversed by the topside ionospheric satellite ISIS 2 near dusk in the L range 2-5.4. The locations of the Explorer 45 plasmapause crossings during this month were compared to the latitudinal decreases of the H(+) density observed on ISIS 2 near the same magnetic field lines. The equatorially determined plasmapause field lines typically passed through or poleward of the minimum of the ionospheric light ion trough, with coincident satellite passes occurring for which the L separation between the plasmapause and trough field lines was between 1 and 2. Vertical flows of the H(+) ions in the light ion trough as detected by the magnetic ion mass spectrometer on ISIS were directed upward with velocities between 1 and 2 kilometers/sec near dusk on these passes. These velocities decreased to lower values on the low latitude side of the H(+) trough but did not show any noticeable change across the field lines corresponding to the magnetospheric plasmapause.
Far-Field Noise Induced by Bubble near Free Surface
NASA Astrophysics Data System (ADS)
Ye, Xi; Li, Jiang-tao; Liu, Jian-hua; Chen, Hai-long
2018-03-01
The motion of a bubble near the free surface is solved by the boundary element method based on the linear wave equation, and the influence of fluid compressibility on bubble dynamics is analyzed. Based on the solution of the bubble motion, the far-field radiation noise induced by the bubble is calculated using Kirchhoff moving boundary integral equation, and the influence of free surface on far-field noise is researched. As the results, the oscillation amplitude of the bubble is weakened in compressible fluid compared with that in incompressible fluid, and the free surface amplifies the effect of fluid compressibility. When the distance between the bubble and an observer is much larger than that between the bubble and free surface, the sharp wave trough of the sound pressure at the observer occurs. With the increment of the distance between the bubble and free surface, the time of the wave trough appearing is delayed and the value of the wave trough increase. When the distance between the observer and the bubble is reduced, the sharp wave trough at the observer disappears.
Element for use in an inductive coupler for downhole drilling components
Hall, David R.; Hall, Jr., H. Tracy; Pixton, David S.; Dahlgren, Scott; Fox, Joe; Sneddon, Cameron
2006-08-29
The present invention includes an element for use in an inductive coupler in a downhole component. The element includes a plurality of ductile, generally U-shaped leaves that are electrically conductive. The leaves are less than about 0.0625" thick and are separated by an electrically insulating material. These leaves are aligned so as to form a generally circular trough. The invention also includes an inductive coupler for use in downhole components, the inductive coupler including an annular housing having a recess with a magnetically conductive, electrically insulating (MCEI) element disposed in the recess. The MCEI element includes a plurality of segments where each segment further includes a plurality of ductile, generally U-shaped electrically conductive leaves. Each leaf is less than about 0.0625" thick and separated from the otherwise adjacent leaves by electrically insulating material. The segments and leaves are aligned so as to form a generally circular trough. The inductive coupler further includes an insulated conductor disposed within the generally circular trough. A polymer fills spaces between otherwise adjacent segments, the annular housing, insulated conductor, and further fills the circular trough.
NASA Astrophysics Data System (ADS)
Agel, Laurie; Barlow, Mathew; Feldstein, Steven B.; Gutowski, William J.
2018-03-01
Patterns of daily large-scale circulation associated with Northeast US extreme precipitation are identified using both k-means clustering (KMC) and Self-Organizing Maps (SOM) applied to tropopause height. The tropopause height provides a compact representation of the upper-tropospheric potential vorticity, which is closely related to the overall evolution and intensity of weather systems. Extreme precipitation is defined as the top 1% of daily wet-day observations at 35 Northeast stations, 1979-2008. KMC is applied on extreme precipitation days only, while the SOM algorithm is applied to all days in order to place the extreme results into the overall context of patterns for all days. Six tropopause patterns are identified through KMC for extreme day precipitation: a summertime tropopause ridge, a summertime shallow trough/ridge, a summertime shallow eastern US trough, a deeper wintertime eastern US trough, and two versions of a deep cold-weather trough located across the east-central US. Thirty SOM patterns for all days are identified. Results for all days show that 6 SOM patterns account for almost half of the extreme days, although extreme precipitation occurs in all SOM patterns. The same SOM patterns associated with extreme precipitation also routinely produce non-extreme precipitation; however, on extreme precipitation days the troughs, on average, are deeper and the downstream ridges more pronounced. Analysis of other fields associated with the large-scale patterns show various degrees of anomalously strong moisture transport preceding, and upward motion during, extreme precipitation events.
Large-Scale Meteorological Patterns Associated with Extreme Precipitation in the US Northeast
NASA Astrophysics Data System (ADS)
Agel, L. A.; Barlow, M. A.
2016-12-01
Patterns of daily large-scale circulation associated with Northeast US extreme precipitation are identified using both k-means clustering (KMC) and Self-Organizing Maps (SOM) applied to tropopause height. Tropopause height provides a compact representation of large-scale circulation patterns, as it is linked to mid-level circulation, low-level thermal contrasts and low-level diabatic heating. Extreme precipitation is defined as the top 1% of daily wet-day observations at 35 Northeast stations, 1979-2008. KMC is applied on extreme precipitation days only, while the SOM algorithm is applied to all days in order to place the extreme results into a larger context. Six tropopause patterns are identified on extreme days: a summertime tropopause ridge, a summertime shallow trough/ridge, a summertime shallow eastern US trough, a deeper wintertime eastern US trough, and two versions of a deep cold-weather trough located across the east-central US. Thirty SOM patterns for all days are identified. Results for all days show that 6 SOM patterns account for almost half of the extreme days, although extreme precipitation occurs in all SOM patterns. The same SOM patterns associated with extreme precipitation also routinely produce non-extreme precipitation; however, on extreme precipitation days the troughs, on average, are deeper and the downstream ridges more pronounced. Analysis of other fields associated with the large-scale patterns show various degrees of anomalously strong upward motion during, and moisture transport preceding, extreme precipitation events.
NASA Astrophysics Data System (ADS)
Tanikawa, W.; Masaki, Y.; Komori, S.; Torimoto, J.; Makio, M.; Ohta, Y.; Nozaki, T.; Ishibashi, J. I.; Kumagai, H.; Maeda, L.; Hamada, Y.
2016-12-01
The middle Okinawa trough, along the Ryukyu-arc on the margin of the western Pacific, fosters several hydrothermal fields. The cruise CK16-01 of D/V CHIKYU targeted the Iheya-North Field and Noho hydrothermal site. More than ten-days extensive coring was carried out with Logging While Drilling (LWD) and deployment of Kuroko cultivation apparatus between February 29th to March 17th2016. Here we present the results of the physical property measurements obtained using Chikyu's on-board laboratory. Cores were sampled among three sites where the seafloor environments were quite different: the Noho site (C9017), a site between the Natsu and Aki sites of the Iheya-North field (C9021), and the Iheya-North Aki site (C9023). Site C9017 was near the center of the hydrothermal activity, and the obtained core was limited 36 m in length and 30 % in the recovery rate. At 70 mbsf (meters below seafloor), the grain density and bulk density of the sediment reached their maxim (3.7 g/m3 and 2.7 g/cm3, respectively), while thermal conductivity reached its lowest value (0.6 W/m·K). Site C9021 yielded a 54 m core, with a core recovery rate of 50 %. Coarse pumiceous layers were found at 68 mbsf, with a hydrothermally altered layer appearing below 68 mbsf. The mean grain density value was 2.4 g/cm3 and was uniform throughout the core. The mean bulk density value of the pumiceous layers was 1.3 g/cm3, and of the hydrothermally altered layer was 2.1 g/cm3. Site C9023 was close to the active hydrothermal chimneys of the Iheya-North Aki site, and yielded 33 m of core with a core recovery rate of 16 %. Massive sulfide layers were found below 48 mbsf with grain density and bulk density values varying between 2.8-4.7 g/cm3 and 1.5-3.9 g/cm3, respectively. Magnetic susceptibility exhibited a high anomaly in a sedimented anhydrite layer found between 95 and 135 mbsf, and a high porosity and low resistivity zone was found below 150 mbsf. Together, these data from drilling cores and onboard analysis provide the first insights into the physical properties of hydrothermal fields in the Okinawa trough. This work was supported by the Council for Science, Technology and Innovation (CSTI) Cross-ministerial Strategic Innovation Promotion Program (SIP), "Next-generation technology for ocean resources exploration" (Lead agency: JAMSTEC)
3D-seismic observations of Late Pleistocene glacial dynamics on the central West Greenland margin
NASA Astrophysics Data System (ADS)
Hofmann, Julia; Knutz, Paul; Cofaigh, Colm Ó.
2016-04-01
Fast-flowing ice streams and outlet glaciers exert a major control on glacial discharge from contemporary and palaeo ice sheets. Improving our understanding of the extent and dynamic behaviour of these palaeo-ice streams is therefore crucial for predictions of the response of ice sheets to present and future climate warming and the associated implications for global sea level. This poster presents results from two 3D-seismic surveys located on the shelf adjoining the Disko Bay trough-mouth fan (TMF), one of the largest glacial outlet systems in Greenland. Located at the seaward terminus of the c. 370 km long cross-shelf Disko Trough, the Disko Bay TMF was generated by highly efficient subglacial sediment delivery onto the continental slopes during repeated ice-stream advances. A variety of submarine glacial landform assemblages are recognised on the seabed reflecting past ice-stream activity presumably related to glacial-interglacial cycles. The 3D-seismic volumes cover the shallow banks located north and south of the Disko Trough. The focus of this study is the seabed and the uppermost stratigraphic interval associated with the Late Stage of TMF development, presumably covering the late Pleistocene (Hofmann et al., submitted). Seabed morphologies include multiple sets of ridges up to 20 m high that extend in NW-SE direction for c. 30 km, and cross-cutting curvilinear furrows with maximum lengths of c. 9 km and average depths of c. 4.5 m. Back-stepping, arcuate scarps facing NW define the shelf break on the northern survey, comprising average widths of c. 4.5 km and incision depths of c. 27.5 m. The large transverse ridge features on the southern survey are likely ice-marginal and are interpreted as terminal moraine ridges recording the existence of a shelf-edge terminating, grounded Late Weichselian ice sheet. The furrows, most prominent on the outer shelf adjoining the shallow banks and partly incising the moraine ridges, are interpreted as iceberg ploughmarks suggesting the transition between grounded ice and a glacimarine setting. The back-stepping scarps are suggestive of slide scars that were created as a result of mass movement induced by instabilities along the NW slope. The buried section contains morphologies indicating an asymmetric feature with a steeper side facing south. It comprises a thickness of c. 100 m and a length of c. 28 km. The detailed surface observations and seismic geometries suggest that the northern area represents a relict grounding-zone wedge (GZW). The wedge is covered by stratified deposits suggesting that it was at least occasionally submarine after its formation and may have served as pinning-point for floating ice shelves during periods of the Late TMF Stage. Important implications of the study are the intermittent development of floating ice shelves during the course of the Late Stage of TMF development and the presence of shelf-edge terminating grounded Late Weichselian ice outside of the troughs. Hofmann, J.C., Knutz, P.C., Nielsen, T., Kuijpers, A., submitted. Seismic architecture and evolution of the Disko Bay trough-mouth fan, central West Greenland margin. Quaternary Science Reviews.
Late Weichselian ice-sheet dynamics and deglaciation history of the northern Svalbard margin
NASA Astrophysics Data System (ADS)
Fransner, O.; Noormets, R. R. N. N.; Flink, A.; Hogan, K.; Dowdeswell, J. A.; O'Regan, M.; Jakobsson, M.
2016-12-01
The glacial evolution of the northern Svalbard margin is poorly known compared with the western margin. Gravity cores, swath bathymetric, sub-bottom acoustic and 2D airgun data are used to investigate the Late Weichselian Svalbard-Barents Ice Sheet history on the northern Svalbard margin. Prograding sequences in Kvitøya and Albertini trough mouths (TMs) indicate ice streaming to the shelf edge multiple times during the Quaternary. While Kvitøya Trough has an associated trough-mouth fan (TMF), Albertini TM is cut back into the shelf edge. Down-faulted bedrock below Albertini TM suggests larger sediment accommodation space there, explaining the absence of a TMF. The bathymetry indicates that ice flow in Albertini Trough was sourced from Duvefjorden and Albertinibukta. Exposed crystalline bedrock likely kept the two ice flows separated before merging north of Karl XII-Øya. Subglacial landforms in Rijpfjorden and Duvefjorden indicate that both fjords accommodated northward-flowing ice streams during the LGM. The deeper fjord basin and higher elongation ratios of landforms in Duvefjorden suggest a more focused and/or larger ice flow there. Easily erodible sedimentary rocks are common in Duvefjorden, which may explain different ice flow dynamics in these fjords. Kvitøya TMF is flanked by gullies, probably formed through erosive downslope gravity flows triggered by sediment-laden meltwater during early deglaciation. Glacial landforms in Albertini Trough comprise retreat-related landforms indicating slow deglaciation. Iceberg scours in Albertini Trough suggest the importance of calving for mass-loss. Sets of De Geer moraines in Rijpfjorden imply that slow, grounded retreat continued in <210 m water depth. Lack of retreat-related landforms in deeper areas of Rijpfjorden and in Duvefjorden indicates floating glacier fronts influenced by calving. 14C ages suggest that deglaciation of inner Rijpfjorden and central Duvefjorden were complete before 10,434 cal a BP and 10,779 cal a BP respectively.
Finch, Natalie A.; Zasowski, Evan J.; Murray, Kyle P.; Mynatt, Ryan P.; Zhao, Jing J.; Yost, Raymond; Pogue, Jason M.
2017-01-01
ABSTRACT Evidence suggests that maintenance of vancomycin trough concentrations at between 15 and 20 mg/liter, as currently recommended, is frequently unnecessary to achieve the daily area under the concentration-time curve (AUC24) target of ≥400 mg · h/liter. Many patients with trough concentrations in this range have AUC24 values in excess of the therapeutic threshold and within the exposure range associated with nephrotoxicity. On the basis of this, the Detroit Medical Center switched from trough concentration-guided dosing to AUC-guided dosing to minimize potentially unnecessary vancomycin exposure. The primary objective of this analysis was to assess the impact of this intervention on vancomycin-associated nephrotoxicity in a single-center, retrospective quasi-experiment of hospitalized adult patients receiving intravenous vancomycin from 2014 to 2015. The primary analysis compared the incidence of nephrotoxicity between patients monitored by assessment of the AUC24 and those monitored by assessment of the trough concentration. Multivariable logistic and Cox proportional hazards regression examined the independent association between the monitoring strategy and nephrotoxicity. Secondary analysis compared vancomycin exposures (total daily dose, AUC, and trough concentrations) between monitoring strategies. Overall, 1,280 patients were included in the analysis. After adjusting for severity of illness, comorbidity, duration of vancomycin therapy, and concomitant receipt of nephrotoxins, AUC-guided dosing was independently associated with lower nephrotoxicity by both logistic regression (odds ratio, 0.52; 95% confidence interval [CI], 0.34 to 0.80; P = 0.003) and Cox proportional hazards regression (hazard ratio, 0.53; 95% CI, 0.35 to 0.78; P = 0.002). AUC-guided dosing was associated with lower total daily vancomycin doses, AUC values, and trough concentrations. Vancomycin AUC-guided dosing was associated with reduced nephrotoxicity, which appeared to be a result of reduced vancomycin exposure. PMID:28923869
Fukumori, S; Tsuji, Y; Mizoguchi, A; Kasai, H; Ishibashi, T; Iwamura, N; To, H
2016-08-01
The pharmacokinetic-pharmacodynamic parameter that best predicts the efficacy of vancomycin is the ratio of the area under the concentration versus time curve (AUC) to the minimum inhibitory concentration (MIC). A 24-h AUC (AUC24 )/MIC ratio ≥ 400 was recommended in an American consensus review, but vancomycin treatment occasionally fails despite maintenance of AUC24 /MIC ≥ 400. We evaluated the association between clinical efficacy of vancomycin and two novel pharmacokinetic parameters, the 'area under the trough level' (AUTL) and the 'area above the trough level' (AATL), in hospitalized elderly patients with methicillin-resistant Staphylococcus aureus (MRSA) pneumonia. The subjects were hospitalized elderly patients who were administered vancomycin for treatment of MRSA pneumonia between 2006 and 2012 at Sasebo Chuo Hospital (Nagasaki, Japan). Pharmacokinetic parameters of vancomycin were estimated for each patient by Bayesian analysis using population pharmacokinetic parameters for Japanese patients. Based on the patient-specific parameters thus obtained, AUC24 values were calculated as the vancomycin dosage divided by vancomycin clearance. AUTL was calculated as the trough serum concentration multiplied by 24 h, whereas AATL was calculated by subtracting AUTL from AUC24 . Logistic regression analysis demonstrated that efficacy of vancomycin was more strongly associated with AUTL than AUC24 . The optimal cut-off value of AUTL was 331 μg∙h/mL, which means that the optimal cut-off value of the trough serum concentration was 13·8 μg/mL. Efficacy of vancomycin was associated with AUTL, a novel pharmacokinetic parameter. Determining the target AUTL or trough concentration may enhance the efficacy of vancomycin therapy in elderly patients with MRSA pneumonia. Given that nephrotoxicity may increase with a Ctrough in excess of 15 μg/mL, this level should ideally not be exceeded. © 2016 John Wiley & Sons Ltd.
Effect of raltegravir on the total and unintegrated proviral HIV DNA during raltegravir-based HAART.
Nicastri, Emanuele; Tommasi, Chiara; Abbate, Isabella; Bonora, Stefano; Tempestilli, Massimo; Bellagamba, Rita; Viscione, Magdalena; Rozera, Gabriella; Gallo, Anna L; Ivanovic, Jelena; Amendola, Alessandra; Pucillo, Leopoldo; Di Perri, Giovanni; Capobianchi, Maria R; Narciso, Pasquale
2011-01-01
Raltegravir is the first approved antiretroviral able to prevent HIV genome integration into the host chromosomes. The aim of the study is to test if raltegravir plasma concentrations can be associated with proviral DNA decline during raltegravir-based salvage therapy. A total of 33 multidrug-resistant HIV-infected patients were enrolled in a longitudinal open-label pilot study and completed a 24-week follow-up. The CD4(+) T-cell count, plasma viral load, proviral HIV DNA and two-long-terminal repeat (2-LTR) circular forms were assessed at baseline, day 14, 30, 60, 90 and 180. The raltegravir trough concentration (C (trough)) was measured by HPLC-ultraviolet and patients were divided into two groups according to the median raltegravir C (trough). The mean±SD values of baseline HIV RNA, CD4(+) T-cell count and HIV DNA were 4.4±0.82 log copies/ml, 256±177 cells/mm(3) , and 2,668±4,721 copies/10(6) peripheral blood mononuclear cells, respectively. Despite a transient increase of total DNA at week 2, a marked proviral DNA decay (P=0.01) with an increase of the 2-LTR unintegrated/total DNA ratio (P=0.06) over time was observed. At univariate analysis, no correlation between raltegravir C(trough) and classical virological parameters was observed. Nevertheless, the decay of proviral HIV DNA was more pronounced in patients displaying C(trough)<158 ng/ml with respect to those with C(trough)>158 ng/ml (P=0.046). Successful raltegravir-based therapy produces a significant decline in proviral DNA and is associated with an increase of the unintegrated/total DNA ratio. Further studies are necessary to define the possible role of pharmacokinetic raltegravir monitoring and the biological meaning of unintegrated proviral DNA. © 2011 International Medical Press
Finch, Natalie A; Zasowski, Evan J; Murray, Kyle P; Mynatt, Ryan P; Zhao, Jing J; Yost, Raymond; Pogue, Jason M; Rybak, Michael J
2017-12-01
Evidence suggests that maintenance of vancomycin trough concentrations at between 15 and 20 mg/liter, as currently recommended, is frequently unnecessary to achieve the daily area under the concentration-time curve (AUC 24 ) target of ≥400 mg · h/liter. Many patients with trough concentrations in this range have AUC 24 values in excess of the therapeutic threshold and within the exposure range associated with nephrotoxicity. On the basis of this, the Detroit Medical Center switched from trough concentration-guided dosing to AUC-guided dosing to minimize potentially unnecessary vancomycin exposure. The primary objective of this analysis was to assess the impact of this intervention on vancomycin-associated nephrotoxicity in a single-center, retrospective quasi-experiment of hospitalized adult patients receiving intravenous vancomycin from 2014 to 2015. The primary analysis compared the incidence of nephrotoxicity between patients monitored by assessment of the AUC 24 and those monitored by assessment of the trough concentration. Multivariable logistic and Cox proportional hazards regression examined the independent association between the monitoring strategy and nephrotoxicity. Secondary analysis compared vancomycin exposures (total daily dose, AUC, and trough concentrations) between monitoring strategies. Overall, 1,280 patients were included in the analysis. After adjusting for severity of illness, comorbidity, duration of vancomycin therapy, and concomitant receipt of nephrotoxins, AUC-guided dosing was independently associated with lower nephrotoxicity by both logistic regression (odds ratio, 0.52; 95% confidence interval [CI], 0.34 to 0.80; P = 0.003) and Cox proportional hazards regression (hazard ratio, 0.53; 95% CI, 0.35 to 0.78; P = 0.002). AUC-guided dosing was associated with lower total daily vancomycin doses, AUC values, and trough concentrations. Vancomycin AUC-guided dosing was associated with reduced nephrotoxicity, which appeared to be a result of reduced vancomycin exposure. Copyright © 2017 American Society for Microbiology.
NCAR CCM2 simulation of the modern Antarctic climate
NASA Technical Reports Server (NTRS)
Tzeng, Ren-Yow; Bromwich, David H.; Parish, Thomas R.; Chen, Biao
1994-01-01
The National Center for Atmospheric Research (NCAR) community climate model version 2 (CCM2) simulation of the circumpolar trough, surface air temperature, the polar vortex, cloudiness, winds, and atmospheric moisture and energy budgets are examined to validate the model's representation of the present-day Antarctic climate. The results show that the CCM2 can well simulate many important climate features over Antarctica, such as the location and intensity of the circumpolar trough, the coreless winter over the plateau, the intensity and horizontal distribution of the surface inversion, the speed and streamline pattern of the katabatic winds, the double jet stream feature over the southern Indian and Pacific oceans, and the arid climate over the continent. However, there are also some serious errors in the model. Some are due to old problems but some are caused by the new parameterizations in the model. The model errors over high southern latitudes can be summarized as follows: The circumpolar trough, the polar vertex, and the westerlies in midlatitudes are too strong; the semiannual cycle of the circumpolar trough is distorted compared to the observations; the low centers of the circumpolar trough and the troughs in the middle and upper troposphere are shifted eastward by 15 deg - 40 deg longitude; the surface temperatures are too cold over the plateau in summer and over the coastline in winter; the polar tropopause continues to have a cold bias; and the cloudiness is too high over the continent. These biases are induced by two major factors: (1) the cloud optical properties in tropical and middle latitudes, which cause the eastward shift of troughs and surface low centers and the error in the semiannual cycle, and (2) the cold bias of the surface air temperature, which is attributed to the oversimulation of cloudiness over the continent, especially during summer, and the uniform 2-m-thick sea ice. The constant thickness of sea ice suppresses the energy flux from the ocean to the atmosphere and hence reduces the air temperature near the coast during winter. Finally, although the simulated Antarctic climate still suffers these biases, the overall performance of the CCM2 is much better than that of the CCM1-T42. Therefore the CCM2 is good enough to be used for climate change studies, especially over Antarctica.
Near-term viability of solar heat applications for the federal sector
NASA Astrophysics Data System (ADS)
Williams, T. A.
1991-12-01
Solar thermal technologies are capable of providing heat across a wide range of temperatures, making them potentially attractive for meeting energy requirements for industrial process heat applications and institutional heating. The energy savings that could be realized by solar thermal heat are quite large, potentially several quads annually. Although technologies for delivering heat at temperatures above 100 C currently exist within industry, only a fairly small number of commercial systems have been installed to date. The objective of this paper is to investigate and discuss the prospects for near term solar heat sales to federal facilities as a mechanism for providing an early market niche to the aid the widespread development and implementation of the technology. The specific technical focus is on mid-temperature (100 to 350 C) heat demands that could be met with parabolic trough systems. Federal facilities have several features relative to private industry that may make them attractive for solar heat applications relative to other sectors. Key features are specific policy mandates for conserving energy, a long term planning horizon with well defined decision criteria, and prescribed economic return criteria for conservation and solar investments that are generally less stringent than the investment criteria used by private industry. Federal facilities also have specific difficulties in the sale of solar heat technologies that are different from those of other sectors, and strategies to mitigate these difficulties will be important. For the baseline scenario developed in this paper, the solar heat application was economically competitive with heat provided by natural gas. The system levelized energy cost was $5.9/MBtu for the solar heat case, compared to $6.8/MBtu for the life cycle fuel cost of a natural gas case. A third-party ownership would also be attractive to federal users, since it would guarantee energy savings and would not need initial federal funds.
NASA Astrophysics Data System (ADS)
Yasuda, K.; Tadokoro, K.; Ikuta, R.; Watanabe, T.; Nagai, S.; Sayanagi, K.
2013-12-01
Observation of seafloor crustal deformation is crucial for megathrust earthquake because most of the focal areas are located below seafloor. Seafloor crustal deformation can be observed GPS/Acoustic technique, and this technique has been carried out at subduction margins in Japan, e.g., Japan Trench, Suruga Trough, and Nankai Trough. At the present, the accuracy of seafloor positioning is one to several centimeters for each epoch. Velocity vectors at seafloor site are estimated through repeated observations. Co- and post- seismic slip distribution and interseismic deformation are estimated from results of seafloor geodetic measurement (e.g., Iinuma et al., 2012; Tadokoro et al., 2012). We repeatedly observed seafloor crustal deformations at two sites across the Suruga Trough from 2005 to investigate interplate locking condition at the focal area of the anticipated megathrust, Tokai, earthquake. We observed 12 and 16 times at an east site of the Suruga Trough (SNE) and at an west site of the Suruga Trough (SNW), respectively. We reinstalled seafloor benchmarks at both sites because of run out of batteries in 2012. We calculated and removed the bias between the old and new seafloor benchmarks. Furthermore, we evaluated two type of analysis. One is Fixed triangular configuration Analysis (FTA). When we determine the seafloor benchmark position, we fix the triangular configuration of seafloor units averaging all the measurements to improve trade-off relation between seafloor benchmark position and sound speed structure. Sound speed structure is assumed to be horizontal layered structure. The other one is Fixed Triangle and Gradient structure of sound speed structure (FTGA). We fixed triangular configuration same as FTA. Sound speed structure is assumed to have gradient structure. Comparing FTA with FTGA, the RMS of horizontal position analyzed through FTA is smaller than that through FTGA at SNE site. On the other hand, the RMS of horizontal position analyzed through FTA is larger than that through FTGA at SNW site. We estimated the displacement velocities with relative to the Amurian plate from the result of repeated observation. The estimated displacement velocity vectors at SNE and SNW are 42×8 mm/y to N94W direction and 46×13 mm/y to N77W direction, respectively. The directions are the same as those measured at the on-land GPS stations. The magnitudes of velocity vector indicate significant shortening by approximately 11 mm/y between SNW and on-land GPS stations at the western part of the Suruga Trough. We also calculated the theoretical surface deformation pattern to depict the interplate locking condition. These results show that the plate interface at the shallow zone of the northernmost Suruga trough is strongly locked.
NASA Astrophysics Data System (ADS)
Alt, Jeffrey C.; Shanks, Wayne C., III; Jackson, Michael C.
1993-10-01
The sulfur contents and sulfur isotopic compositions of 24 glassy submarine volcanics from the Mariana Island Arc and back-arc Mariana Trough were determined in order to investigate the hypothesis that subducted seawater sulfur (delta S-34 = 21 parts per thousand) is recycled through arc volcanism. Our results for sulfur are similar to those for subaerial arc volcanics: Mariana Arc glasses are enriched in S-34(delta S-34 = up to 10.3 parts per thousand, mean = 3.8 parts per thousand) and depleted in S(20-290 ppm, mean = 100 ppm) relative to mid ocean ridge basalt (MORB)(850 ppm S, delta S-34 = 0.1 +/- 0.5 parts per thousand). The bac-arc trough basalts contain 200-930 ppm S and have delta S-34 values of 1.1 +/- 0.5 parts per thousand, which overlap those for the arc and MORB. The low sulfur contents of the arc and some of the trough glasses are attributed to (1) early loss of small amounts of sulfur through separation of immiscible sulfide and (2) later vapor-melt equilibrium control of sulfur contents and loss of sulfur in a vapor phase from sulfide-undersaturated melts near the minimum in sulfur solubility at fO2 is approximately equal to NNO (nickel-nickel oxide). Although these processes removed sulfur from the melts their effects on the sulfur isotopic compositions of the melts were minimal. Positive trends of delta S-34 with Sr-87/Sr-86 large ion lithophile element (LILE) and Light rare earth elements (LREE) contents of the arc volcanics are consistent with a metasomatic seawater sulfur component in the depleted sub-arc mantle source. The lack of a S-34-rich slab signature in the trough lavas may be attributed to equilibration of metasomatic fluid with mantle material along the longer pathway from the slab to the source of the trough volcanics. Sulfur is likely to have been transported into the mantle wedge by metasomatic fluid derived from subducted sediments and pore fluids. Gases extracted from vesicles in arc and back-arc samples are predominantly H2O, with minor CO2 and traces of H2S and SO2.CO2 in the arc and back-arc rocks has delta C-13 values of -2.1 to 13.1 parts per thousand, similar to MORB. These data suggest that degassing of CO2 could explain the slightly lower delta C-13 values for some Mariana Trough volcanic glasses, and that incorporation of subduction-derived organic carbon into the Mariana trough mantle source may not be necessary. More analyses are required to resolve this question, however.
Technology for communicational development and learning in psychomotor disability
NASA Astrophysics Data System (ADS)
Trento, I.; Santucci, M.; Tula, S.; González, E.
2007-11-01
The applied investigation and experimental development project described in this paper has been carried out by Grupo Ingeniería Clínica of the Universidad Tecnológica Nacional together with two Special Education Schools dependent on the Ministry of Education of Córdoba Province. Its aim is the development of computer access assistive tools for students with mobility limitations, and with or without intellectual problems that need adaptations to access to a computer in order to learn, communicate, work, etc. On the other hand, it demonstrates the benefits that the use of a computer gives to these students. The evaluation of their performance was made trough Dr. Marianne Frostig's Developmental Test of Visual Perception and reading and writing graphic tests, comparing the results of the tests made on paper with those made on computer. Thus, an interdisciplinary team was formed by Engineering, Psychology and Special Education professionals, and 40 students were evaluated. The design of the mouse and keyboard had some adaptations. At present, the rating test stage is being achieved, and the preliminary results allow us to anticipate that pupils with psychomotor disabilities may manifest their perceptual ripeness and reach education in a more efficient way through the use of informatics tools according to their needs and possibilities.
USDA-ARS?s Scientific Manuscript database
An obstacle to sunshine bass (female white bass Morone chrysops × male striped bass M. saxatilis) larval production is fungal growth on eggs caused by the water-mold Saprolegnia spp. Copper sulfate (CuSO4) is commonly used for fungus control in troughs of catfish hatcheries, but the effectiveness o...
The Rome trough and evolution of the Iapetean margin
DOE Office of Scientific and Technical Information (OSTI.GOV)
Walker, D.; Hamilton-Smith, T.; Drahovzal, J.A.
1991-08-01
Recent structural mapping of the Rome trough suggests a complex structure very different from the symmetrical and laterally continuous graben commonly depicted. Early and Middle Cambrian extension in the Rome trough of eastern Kentucky and adjacent areas resulted in a series of alternately facing half-grabens with variable displacement. These half-grabens are bounded by southwest-northeast-trending normal faults (e.g., Kentucky River and Warfield faults), which are laterally continuous only on the order to tens of kilometers. The Rome trough is laterally segmented by north-south-trending faults (e.g., Lexington fault) commonly expressed as flexures in younger rocks (e.g., Burning Springs anticline and Floyd Countymore » channel). Many of these north-south-trending faults have significant left-lateral displacement, and probably represent reactivated thrust faults of the Grenville tectonic front. The Rome trough and the associated Mississippi Valley, Rough Creek, and Birmingham fault systems were initiated during an Early Cambrian shift in sea-floor spreading from the Blue Ridge-Pine Mountain rift to the Ouachita rift along the Alabama-Oklahoma transform fault. These fault systems have been proposed as having originated from extensional stress propagated northward from the Ouachita rift across the transform fault. In the alternate model proposed here, faulting was brittle, extensional failure resulting form subsidence and flexure of the continental margin to the east. Following initiation of sea-floor spreading at the Blue Ridge-Pine Mountain rift in the latest Proterozoic, margin subsidence in the presence of the Alabama-Oklahoma transform boundary and the inherited Grenville tectonic front resulted in this interior cratonic fault system.« less
Evidence for Recent Liquid Water on Mars: Gullies in Sirenum Fossae Trough
NASA Technical Reports Server (NTRS)
2000-01-01
This mosaic of two Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images shows about 20 different gullies coming down the south-facing wall of a trough in the Sirenum Fossae/Gorgonum Chaos region of the martian southern hemisphere. Each channel and its associated fan--or apron--of debris appears to have started just below the same hard, resistant layer of bedrock located approximately 100 meters (about 325 feet) below the top of the trough wall. The layer beneath this hard, resistant bedrock is interpreted to be permeable, which allows ground water to percolate through it and--at the location of this trough--seep out onto the martian surface. The channels and aprons only occur on the south-facing slope of this valley created by faults on each side of the trough. The depression is approximately 1.4 km (0.9 mi) across.The mosaic was constructed from two pictures taken on September 16, 1999, and May 1, 2000. The black line is a gap between the two images that was not covered by MOC. The scene covers an area approximately 5.5 kilometers (3.4 miles) wide by 4.9 km (3.0 mi) high. Sunlight illuminates the area from the upper left. The image is located near 38.5oS, 171.3oW. MOC high resolution images are taken black-and-white (grayscale); the color seen here has been synthesized from the colors of Mars observed by the MOC wide angle cameras and by the Viking Orbiters in the late 1970s.Han, Zhe; Pettit, Natasha N; Landon, Emily M; Brielmaier, Benjamin D
2017-04-01
Background: The impact of pharmacy interventions on optimizing vancomycin therapy has been described, however interventions vary among studies and the most optimal pharmacy practice model (PPM) for pharmacokinetic (PK) services has not been established. Objective: The purpose of this study is to demonstrate the value of 24 hours a day, 7 days a week (24/7) PK services. Methods: New PK services were implemented in 2 phases with institutional PPM expansion. Phase 1 included universal monitoring by pharmacists with recommendations made to prescribers during business hours. Phase 2 expanded clinical pharmacists' coverage to 24/7 and provided an optional 24/7 pharmacist-managed PK consult service. We compared vancomycin therapeutic trough attainment, dosing, and clinical and safety outcomes between phases 1 and 2 in adult inpatients receiving therapeutic intravenous vancomycin. Results. One hundred and fifty patients were included in each phase. Phase 2 had a greater proportion of vancomycin courses with therapeutic initial trough concentrations (27.5% vs 46.1%; p = 0.002), higher initial trough concentrations (10.9 mcg/mL vs 16.4 mcg/mL; p < 0.001), and optimized initial vancomycin dosing (13.5 mg/kg vs 16.2 mg/kg; p < 0.001). Phase 2 also saw significant reduction in the incidence of vancomycin-associated nephrotoxicity (21.1% vs 11.7%; p = 0.038). Dose optimization and improvement in initial target trough attainment were most notable among intensive care unit (ICU) patients. Conclusions. Our study demonstrated that 24/7 PK services implemented with institutional PPM expansion optimized vancomycin target trough attainment and improved patient safety.
Synoptic patterns leading to hailstorm in Chaharmahal and Bakhtiari province, Iran
NASA Astrophysics Data System (ADS)
Salahi, Bromand; Nohegar, Ahmad; Behrouzi, Mahmoud; Aalijahan, Mehdi
2018-03-01
The purpose of this study was to extract the synoptic patterns of 500 mb geopotential height and the sea level pressure leading to form hail in Chaharmahal and Bakhtiari province, Iran. To this end, at first, we explored hail occurrence in different areas of the province under investigation. Then, using sea level pressure and 500 mb geopotential height data, the patterns of hail occurrence were investigated through hierarchical clustering and Ward's method. The level of 500 mb patterns resulting in hail formation in the area include: (1) settlement of a cut-off low pressure blocking in Turkey and Iran's position in downstream of trough and injection of humidity coming from the Red Sea; (2) settlement of low ridge in northern Europe and Iran lying in downstream of the trough and injection of humidity of the Mediterranean Sea; (3) settlement of a cut-off low pressure in east of Europe and Iran lying in downstream of the trough; and (4) settlement of a deep trough in the Mediterranean Sea, formation of an omega-shaped blocking in Northern Europe and Iran lying in downstream of the trough. At sea level, the following patterns have caused hail formation in Chaharmahal and Bakhtiari province: (1) settlement of low pressure in Iran and Russia accompanying high pressure in Taklimakan Desert and east of Europe; (2) settlement of low pressure in Iran and high pressure in Egypt, northern Europe, and Taklimakan Desert; and (3) settlement of low pressure in Iran, Saudi Arabia and south of Italy and high pressure in Egypt and Siberia.
Mourad, Michel; Mourad, Georges; Wallemacq, Pierre; Garrigue, Valérie; Van Bellingen, Christophe; Van Kerckhove, Valérie; De Meyer, Martine; Malaise, Jacques; Eddour, Djamila Chaib; Lison, Dominique; Squifflet, Jean Paul; Haufroid, Vincent
2005-10-15
CYP3A5 and MDR1 polymorphisms have been shown to influence tacrolimus blood concentrations and dose requirements. The aim is to determine whether these polymorphisms also affect sirolimus trough concentrations and dose requirements after kidney transplantation. Eighty-five renal transplant recipients receiving sirolimus were included. Twenty-four were treated with a combined sirolimus-tacrolimus regimen. Eighty-one patients received steroids. Sirolimus and tacrolimus were adjusted to a target therapeutic window. CYP3A5 (intron 3) and MDR1 (exons 12, 21, 26) genotypes were correlated to the adjusted trough concentrations and dose requirements for both sirolimus and tacrolimus. There were no significant correlation between adjusted sirolimus trough concentrations or dose requirements and genetic polymorphisms. In a multiple regression model, adjusted-prednisone dose was involved with a positive or negative effect when considering sirolimus dose requirements or adjusted concentrations, respectively. In the subgroup of patients treated by tacrolimus and sirolimus, adjusted tacrolimus doses were higher in patients carrying at least one CYP3A5 *1 allele (median 0.083 vs. 0.035 mg/kg for CYP3A5*3/*3 patients, P<0.05). Adjusted-prednisolone dose and CYP3A5 polymorphism explained up to 61% of the variability in tacrolimus dose requirements. Unlike tacrolimus, sirolimus adjusted trough concentrations and dose requirements seem not affected by CYP3A5 and MDR1 polymorphisms. Adjusted-prednisone dose has a significant impact on tacrolimus and sirolimus dose requirements.
NASA Astrophysics Data System (ADS)
Gaggioli, Walter; Di Ascenzi, Primo; Rinaldi, Luca; Tarquini, Pietro; Fabrizi, Fabrizio
2016-05-01
In the frame of the Solar Thermodynamic Laboratory, ENEA has improved CSP Parabolic Trough technologies by adopting new advanced solutions for linear tube receivers and by implementing a binary mixture of molten salt (60% NaNO3 and 40% KNO3) [1] as both heat transfer fluid and heat storage medium in solar field and in storage tanks, thus allowing the solar plants to operate at high temperatures up to 550°C. Further improvements have regarded parabolic mirror collectors, piping and process instrumentation. All the innovative components developed by ENEA, together with other standard parts of the plant, have been tested and qualified under actual solar operating conditions on the PCS experimental facility at the ENEA Casaccia Research Center in Rome (Italy). The PCS (Prova Collettori Solari, i.e. Test of Solar Collectors) facility is the main testing loop built by ENEA and it is unique in the world for what concerns the high operating temperature and the fluid used (mixture of molten salt). It consists in one line of parabolic trough collectors (test section of 100 m long life-size solar collectors) using, as heat transfer fluid, the aforesaid binary mixture of molten salt up to 10 bar, at high temperature in the range 270° and 550°C and a flow rate up to 6.5 kg/s. It has been working since early 2004 [2] till now; it consists in a unique closed loop, and it is totally instrumented. In this paper the effects of over ten years qualification tests on the pressurized tank will be presented, together with the characterization of the thermal losses of the piping of the molten salt circuit, and some observations performed on the PCS facility during its first ten years of operation.
Continental breakup by oblique extension: the Gulf of California
NASA Astrophysics Data System (ADS)
van Wijk, J.; Axen, G. J.
2017-12-01
We address two aspects of oblique extension: 1) the evolution of pull-apart basins, and how/when they may evolve into seafloor spreading segments; and 2) the formation of microcontinents. The Gulf of California formed by oblique extension. Breakup resulted in oceanic crust generation in the southern and central parts, while in the northern Gulf/Salton Trough a thick layer of (meta-)sediments overlies thinned continental crust. We propose a simple mechanism to explain this N-S variation. We assume that oblique rifting of the proto-Gulf province resulted in pull-apart basins, and use numerical models to show that such pull-apart basins do not develop into seafloor spreading segments when their length-to-width ratios are small, as is the case in the northern Gulf. In the central and southern Gulf the length-to-width ratios were larger, promoting continent rupture. The mechanisms behind this fate of pull-apart basins will be discussed in the presentation. In the southern Gulf, potential field models show that the Tamayo Bank in the southern Gulf is likely a microcontinent, separated from the main continent by the Tamayo trough. The thickness of the ocean crust in the Tamayo trough is anomalously small, suggesting that initial seafloor spreading was magma-starved and unsuccessful, causing the location of rifting and seafloor spreading to jump. As a consequence a sliver of continent broke off, forming the microcontinent. We suggest that worldwide this may be a common process for microcontinent formation.
New Insight Into The Crustal Structure of The Continental Margin Off NW Sabah/borneo
NASA Astrophysics Data System (ADS)
Barckhausen, U.; Franke, D.; Behain, D.; Meyer, H.
The continental margin offshore NW Sabah/Borneo (Malaysia) has been investigated with reflection and refraction seismics, magnetics, and gravity during the recent cruise BGR01-POPSCOMS. A total of 4000 km of geophysical profiles has been acquired, thereof 2900 km with reflection seismics. Like in major parts of the South China Sea, the area seaward of the Sabah Trough consists of extended continental lithosphere. We found evidence that the continental crust also underlies the continental slope land- ward of the Trough, a fact that raises many questions about the tectonic history and development of this margin. The characteristic pattern of rotated fault blocks and half grabens and the carbon- ates which are observed all over the Dangerous Grounds can be traced a long way landward of the Sabah Trough beneath the sedimentary succession of the upper plate. The magnetic anomalies which are dominated by the magnetic signatures of relatively young volcanic features also continue under the continental slope. The sedimentary rocks of the upper plate, in contrast, seem to generate hardly any magnetic anoma- lies. We suspect that the volcanic activity coincided with the collision of Borneo and the Dangerous Grounds in middle or late Miocene time. The emplacement of an al- lochtonous terrane on top of the extended continental lithosphere could be explained by overthrusting as a result of the collision or it could be related to gravity sliding following a broad uplift of NW Borneo at the same time.
Determining the Nature of Late Gunn–Peterson Troughs with Galaxy Surveys
NASA Astrophysics Data System (ADS)
Davies, Frederick B.; Becker, George D.; Furlanetto, Steven R.
2018-06-01
Recent observations have discovered long (up to ∼110 Mpc/h), opaque Gunn–Peterson troughs in the z ∼ 5.5 Lyα forest, which are challenging to explain with conventional models of the post-reionization intergalactic medium. Here, we demonstrate that observations of the galaxy populations in the vicinity of the deepest troughs can distinguish two competing models for these features: deep voids where the ionizing background is weak due to fluctuations in the mean free path of ionizing photons would show a deficit of galaxies, while residual temperature variations from extended, inhomogeneous reionization would show an overdensity of galaxies. We use large (∼550 Mpc/h) semi-numerical simulations of these competing explanations to predict the galaxy populations in the largest of the known troughs at z ∼ 5.7. We quantify the strong correlation of Lyα effective optical depth and galaxy surface density in both models, and estimate the degree to which realistic surveys can measure such a correlation. While a spectroscopic galaxy survey is ideal, we also show that a relatively inexpensive narrowband survey of Lyα-emitting galaxies is ∼90% likely to distinguish between the competing models.
Amazonian volcanism inside Valles Marineris on Mars
NASA Astrophysics Data System (ADS)
Brož, Petr; Hauber, Ernst; Wray, James J.; Michael, Gregory
2017-09-01
The giant trough system of Valles Marineris is one of the most spectacular landforms on Mars, yet its origin is still unclear. Although often referred to as a rift, it also shows some characteristics that are indicative of collapse processes. For decades, one of the major open questions was whether volcanism was active inside the Valles Marineris. Here we present evidence for a volcanic field on the floor of the deepest trough of Valles Marineris, Coprates Chasma. More than 130 individual edifices resemble scoria and tuff cones, and are associated with units that are interpreted as lava flows. Crater counts indicate that the volcanic field was emplaced sometime between ∼0.4 Ga and ∼0.2 Ga. The spatial distribution of the cones displays a control by trough-parallel subsurface structures, suggesting magma ascent in feeder dikes along trough-bounding normal faults. Spectral data reveal an opaline-silica-rich unit associated with at least one of the cones, indicative of hydrothermal processes. Our results point to magma-water interaction, an environment of astrobiological interest, perhaps associated with late-stage activity in the evolution of Valles Marineris, and suggest that the floor of Coprates Chasma is promising target for the in situ exploration of Mars.
NASA Technical Reports Server (NTRS)
Selcuk, M. K.
1976-01-01
A solar heat collection system employing non-tracking reflectors integrated with a fixed vacuum tube receiver which achieves modest year-round concentration (about 2) of the sunlight at low capital costs is discussed. The axis of the vee-trough reflector lies in a east-west direction and requires reversal of the reflector surfaces only twice a year without disturbing the receiver tubes and associated plumbing. It collects most of the diffuse flux. The vacuum tube receiver with selective absorber has no convection losses while radiation and conduction losses are minimal. Significant cost reductions are offered since the vee-trough can be fabricated from inexpensive polished or plastic reflector laminated sheet metal covering 2/3 of the collection area, and only about 1/3 of the area is covered with the more expensive vacuum tube receivers. Thermal and economic performance of the vee-trough vacuum tube system, year-round variation of the concentration factor, incident flux, useful heat per unit area at various operation temperatures and energy cost estimates are presented. The electrical energy cost is estimated to be 77 mills/kWh, and the system construction cost is estimated to be $1140/kWe.
Ryder, Robert T.; Harris, Anita G.; Repetski, John E.; revised and digitized by Crangle, Robert D.
2003-01-01
A 275-mi-long restored stratigraphic cross section from Medina County, Ohio, through southwestern and south-central Pennsylvania to Hampshire County, W. Va., provides new details on Cambrian and Ordovician stratigraphy in the central Appalachian basin and the structure of underlying Precambrian basement rocks. From west to east, the major structural elements of the block-faulted basement in this section are (1) the relatively stable, slightly extended craton, which includes the Wooster arch, (2) the fault-controlled Ohio-West Virginia hinge zone, which separates the craton from the adjoining Rome trough, (3) the Rome trough, which consists of an east-facing asymmetric graben and an overlying sag basin, and (4) a positive fault block, named here the South-central Pennsylvania arch, which borders the eastern margin of the graben part of the Rome trough. Pre-Middle Ordovician structural relief on Precambrian basement rocks across the down-to-the-west normal fault that separates the Rome trough and the adjoining South-central Pennsylvania arch amounted to between 6,000 and 7,000 ft. The restored cross section shows eastward thickening of the Cambrian and Ordovician sequence from about 3,000 ft near the crest of the Wooster arch at the western end of the section to about 5,150 ft at the Ohio-West Virginia hinge zone adjoining the western margin of the Rome trough to about 19,800 ft near the depositional axis of the Rome trough. East of the Rome trough, at the adjoining western edge of the South-central Pennsylvania arch, the Cambrian and Ordovician sequence thins abruptly to about 13,500 ft and then thins gradually eastward across the arch to about 12,700 ft near the Allegheny structural front and to about 10,150 ft at the eastern end of the restored section. In general, the Cambrian and Ordovician sequence along this section consists of four major lithofacies that are predominantly shallow marine to peritidal in origin. In ascending stratigraphic order, the lithofacies are identified by the following descriptive names: (1) sandstone, shale, limestone, and dolomite unit, (2) dolomite and sandstone unit, (3) limestone and black shale unit, and (4) shale and sandstone unit. Each of these units and their associated subunits thicken from west to east across the restored section to a maximum near the depositional axis of the Rome trough and then thin eastward to the end of the section. The sandstone, shale, limestone, and dolomite unit is largely confined to the asymmetric graben that marks the initial phase of the Rome trough. This unit is Early and Middle Cambrian in age and consists, in ascending order, of a basal sandstone unit (undrilled but probably present), the Tomstown Dolomite (undrilled but probably present), the Waynesboro Formation, and the Pleasant Hill Limestone and its equivalent lower one-third of the Elbrook Formation at the eastern end of the section. The dolomite and sandstone unit forms the core of the Cambrian and Ordovician sequence. In the Rome trough and on the adjoining South-central Pennsylvania arch, this unit consists, in ascending order, of the Middle and Upper Cambrian Warrior Formation and the equivalent upper two-thirds of the Elbrook Formation at the eastern end of the section, the Upper Cambrian Gatesburg Formation, and the Lower Ordovician and Middle Ordovician (Whiterockian and Chazyan) Beekmantown Group. West of the Ohio-West Virginia hinge zone, the dolomite and sandstone unit consists, in ascending order, of the Conasauga Formation of Janssens (1973), the Krysik sandstone of driller's usage, the B zone of Calvert (1964), the Knox Dolomite and the associated Rose Run Sandstone Member, and the Wells Creek Formation. The widespread Knox unconformity is located at the base of the Wells Creek Formation and at or near the top of the adjoining Beekmantown Group, except near the depositional axis of the Rome trough, where the unconformity seems to be absent. The limestone and black shale unit i
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gomez, J. C.
2011-09-01
It is clearly understood that lower overall costs are a key factor to make renewable energy technologies competitive with traditional energy sources. Energy storage technology is one path to increase the value and reduce the cost of all renewable energy supplies. Concentrating solar power (CSP) technologies have the ability to dispatch electrical output to match peak demand periods by employing thermal energy storage (TES). Energy storage technologies require efficient materials with high energy density. Latent heat TES systems using phase change material (PCM) are useful because of their ability to charge and discharge a large amount of heat from amore » small mass at constant temperature during a phase transformation like melting-solidification. PCM technology relies on the energy absorption/liberation of the latent heat during a physical transformation. The main objective of this report is to provide an assessment of molten salts and metallic alloys proposed as candidate PCMs for TES applications, particularly in solar parabolic trough electrical power plants at a temperature range from 300..deg..C to 500..deg.. C. The physical properties most relevant for PCMs service were reviewed from the candidate selection list. Some of the PCM candidates were characterized for: chemical stability with some container materials; phase change transformation temperatures; and latent heats.« less
Hall, David R [Provo, UT; Hall, Jr., H. Tracy
2007-07-24
A transmission system in a downhole component comprises a data transmission element in both ends of the downhole component. Each data transmission element houses an electrically conducting coil in a MCEI circular trough. The electrically conducting coil comprises at least two generally fractional loops. In the preferred embodiment, the transmission elements are connected by an electrical conductor. Preferably, the electrical conductor is a coaxial cable. Preferably, the MCEI trough comprises ferrite. In the preferred embodiment, the fractional loops are connected by a connecting cable. In one aspect of the present invention, the connecting cable is a pair of twisted wires. In one embodiment the connecting cable is a shielded pair of twisted wires. In another aspect of the present invention, the connecting cable is a coaxial cable. The connecting cable may be disposed outside of the MCEI circular trough.
Contrasting modes of rifting: The Benue Trough and Cameroon Volcanic Line, West Africa
NASA Astrophysics Data System (ADS)
Okereke, C. S.
1988-08-01
The Benue trough of west Africa is commonly believed to be a rift feature that originated in the Cretaceous at about the time that Africa and South America began to separate. Bouguer gravity and available geological data in the trough indicate that its formation was probably the result of regional horizontal stresses in the lithosphere, causing crustal extension and surface subsidence. By contrast, the data for the adjoining Cameroon volcanic line suggests that the associated tensional stresses relate to mantle upwarp causing thinning of the lithosphere and regional crustal uplift similar to that associated with the Kenya rift. Thus the association of passive and active rifts seen in the Afro-Arabia rift system is also a feature of the Cretaceous rift system in west Africa.
Ancient geodynamics and global-scale hydrology on Mars.
Phillips, R J; Zuber, M T; Solomon, S C; Golombek, M P; Jakosky, B M; Banerdt, W B; Smith, D E; Williams, R M; Hynek, B M; Aharonson, O; Hauck , S A
2001-03-30
Loading of the lithosphere of Mars by the Tharsis rise explains much of the global shape and long-wavelength gravity field of the planet, including a ring of negative gravity anomalies and a topographic trough around Tharsis, as well as gravity anomaly and topographic highs centered in Arabia Terra and extending northward toward Utopia. The Tharsis-induced trough and antipodal high were largely in place by the end of the Noachian Epoch and exerted control on the location and orientation of valley networks. The release of carbon dioxide and water accompanying the emplacement of approximately 3 x 10(8) cubic kilometers of Tharsis magmas may have sustained a warmer climate than at present, enabling the formation of ancient valley networks and fluvial landscape denudation in and adjacent to the large-scale trough.
NASA Astrophysics Data System (ADS)
Chappell, A.; Kusznir, N. J.
2005-05-01
The southern Rockall Trough south of 57 N has previously been interpreted as either an intra-continental rift floored with highly extended continental crust, or a failed oceanic rift formed by Cretaceous sea floor spreading. Satellite gravity, bathymetry data and seismic estimates of sediment thickness are used to derive crustal basement thickness for the southern Rockall Trough and adjacent regions using a gravity inversion method incorporating a correction for the large negative thermal gravity component present in oceanic and stretched continental lithosphere. The marine Bouguer anomaly, derived from satellite free air gravity (Sandwell & Smith 1997) and Gebco 2003 bathymetry data, is inverted using the method of Oldenberg (1974), incorporating an iteratively applied thermal anomaly correction, to give Moho depth. For oceanic crust the thermal anomaly correction is calculated using isochron ages (Muller et al. 1997) and for continental crust from the beta stretching factors resulting from gravity derived crustal basement thickness and an assumed rift age. When sediment thickness and volcanic addition are assumed to be zero, the resulting upper bound of crustal thickness from the gravity inversion is as little as 10 km in the southern Rockall Trough. A segmented axial thickening of the crust at the centre of the Rockall Trough is predicted, between the Barra volcanic ridge and the Anton Dohrn seamount and is interpreted as having a volcanic origin. Inclusion of a sediment thickness correction in the gravity inversion further reduces predicted crustal thickness. A pseudo-sediment-thickness map has been constructed from the available wide-angle data and incorporated in the gravity inversion. The addition of up to 5.5 km of sediment in the gravity inversion reduces the upper bound of crustal thickness to less than 3 km in some locations. The segmented axial thickening and thin crust shown by the gravity inversion, the lack of intra-basinal faulting, and the volcanic origin for the axis shown by normal incidence seismic data, are consistent with a sea-floor spreading origin for the southern Rockall Trough and not formation by intra-continental rifting. We investigate the formation of the southern Rockall Trough using SfMargin, a new model of continental lithosphere thinning leading to continental breakup and sea-floor spreading initiation. Comparisons of the geometry of the southern Rockall Trough predicted by SfMargin with that observed are consistent with a short period (20Ma) of slow Cretaceous sea-floor spreading, followed by thermal subsidence to present day. This work forms part of the NERC Margins iSIMM project. iSIMM investigators are from Liverpool and Cambridge Universities, Badley Geoscience & Schlumberger Cambridge Research supported by the NERC, the DTI, Agip UK, BP, Amerada Hess Ltd, Anadarko, ConocoPhillips, Shell, Statoil and WesternGeco. The iSIMM team comprises NJ Kusznir, RS White, AM Roberts, PAF Christie, A Chappell, J Eccles, R Fletcher, D Healy, N Hurst, ZC Lunnon, CJ Parkin, AW Roberts, LK Smith, V Tymms & R Spitzer.
An overview of current activities at the National Solar Thermal Test Facility
NASA Astrophysics Data System (ADS)
Cameron, C. P.; Klimas, P. C.
This paper is a description of the United States Department of Energy's National Solar Thermal Test Facility, highlighting current test programs. In the central receiver area, research underway supports commercialization of molten nitrate salt technology, including receivers, thermal energy transport, and corrosion experiments. Concentrator research includes large-area, glass-metal heliostats and stretched-membrane heliostats and dishes. Test activities in support of dish-Stirling systems with reflux receivers are described. Research on parabolic troughs includes characterization of several receiver configurations. Other test facility activities include solar detoxification experiments, design assistance testing of commercially-available solar hardware, and non-DOE-funded work, including thermal exposure tests and testing of volumetric and PV central receiver concepts.
Western Ross Sea continental slope gravity currents
NASA Astrophysics Data System (ADS)
Gordon, Arnold L.; Orsi, Alejandro H.; Muench, Robin; Huber, Bruce A.; Zambianchi, Enrico; Visbeck, Martin
2009-06-01
Antarctic Bottom Water of the world ocean is derived from dense Shelf Water that is carried downslope by gravity currents at specific sites along the Antarctic margins. Data gathered by the AnSlope and CLIMA programs reveal the presence of energetic gravity currents that are formed over the western continental slope of the Ross Sea when High Salinity Shelf Water exits the shelf through Drygalski Trough. Joides Trough, immediately to the east, offers an additional escape route for less saline Shelf Water, while the Glomar Challenger Trough still farther east is a major pathway for export of the once supercooled low-salinity Ice Shelf Water that forms under the Ross Ice Shelf. The Drygalski Trough gravity currents increase in thickness from ˜100 to ˜400 m on proceeding downslope from ˜600 m (the shelf break) to 1200 m (upper slope) sea floor depth, while turning sharply to the west in response to the Coriolis force during their descent. The mean current pathway trends ˜35° downslope from isobaths. Benthic-layer current and thickness are correlated with the bottom water salinity, which exerts the primary control over the benthic-layer density. A 1-year time series of bottom-water current and hydrographic properties obtained on the slope near the 1000 m isobath indicates episodic pulses of Shelf Water export through Drygalski Trough. These cold (<-1 °C), salty (>34.75) pulses correlate with strong downslope bottom flow. Extreme examples occurred during austral summer/fall 2003, comprising concentrated High Salinity Shelf Water (-1.9 °C; 34.79) and approaching 1.5 m s -1 at descent angles as large as ˜60° relative to the isobaths. Such events were most common during November-May, consistent with a northward shift in position of the dense Shelf Water during austral summer. The coldest, saltiest bottom water was measured from mid-April to mid-May 2003. The summer/fall export of High Salinity Shelf Water observed in 2004 was less than that seen in 2003. This difference, if real, may reflect the influence of the large iceberg C-19 over Drygalski Trough until its departure in mid-May 2003, when there was a marked decrease in the coldest, saltiest gravity current adjacent to Drygalski Trough. Northward transport of cold, saline, recently ventilated Antarctic Bottom Water observed in March 2004 off Cape Adare was ˜1.7 Sv, including ˜0.4 Sv of High Salinity Shelf Water.
Folorunso, O R; Kayode, Sule; Onibon, V O
2014-01-01
Water troughs from deep litter and caged chicken water troughs (drinkers) fixed to each of the different 3-tier cages containing layer chickens in Farms A, B and C were subjected to a 7-day study which involved the monitoring of poultry farm hygiene. Drinkers were washed before filling with water on Day 1. For Days 3, 5 and 7 water was served without prior washing. The occurrence and characterization of the bacteria isolates were investigated and data obtained were analyzed and compared. For the bacterial count on Day 1, for layer chickens on cage system, no significant differences (p > 0.05) among the farms and between the farms tier interactions. On Day 3, no significant difference (p > 0.05) among the parameters. On Day 5, there was significant difference (p<0.05) among the farms and on Day 7, there was high significant difference (p < 0.01) among the farms. On Days 5 and 7, there were no significant differences (p>0.05) among the tiers nor between the interactions of the farms and tiers. The bacterial count in water troughs of layer chickens in deep litter system, on Day 1, had no significant differences (p > 0.05) between the farms, water troughs and their interactions. On Day 3, no significant difference (p > 0.05) among the parameters. On Days 5 and 7, there were significant difference (p<0.05) and a high significant difference (p < 0.01) between the farms respectively. On Days 5 and 7, no significant differences between the water troughs and between the interaction of the farms and the water troughs. Farm A isolates contained Staphylococcus aureus, Proteus vulgaris, Streptococcus faecalis, Escherichia coli, Staphylococcus epidermis, Klebsiella sp., Salmonella sp., Bacillus subtilis, Lactobacillus salivarius and Corynebacterium sp. Farm B had Staphylococcus aureus, S. epidermis, Bacillus subtilis, Corynebacterium sp., Escherichia coli, Streptococcus faecalis and Klebsiella sp. while for Farm C, apart from the prevalent bacteria isolates obtained in Farms A and B, additional 2 bacterial isolates, Lactobacillus salivarius and Pseudomonas aeuriginosa were found. In conclusion, water troughs when cleaned on daily basis carry minimum bacterial load. Those left for 3, 5 and 7 days uncleaned had progressively high bacterial loads, suggesting that the flock of birds and the consumers of the eggs and meat from the chickens are at risk of bacterial infection unless strict farm hygiene is ensured through regular monitoring.
NASA Astrophysics Data System (ADS)
Hirata, K.; Fujiwara, H.; Nakamura, H.; Osada, M.; Morikawa, N.; Kawai, S.; Ohsumi, T.; Aoi, S.; Yamamoto, N.; Matsuyama, H.; Toyama, N.; Kito, T.; Murashima, Y.; Murata, Y.; Inoue, T.; Saito, R.; Takayama, J.; Akiyama, S.; Korenaga, M.; Abe, Y.; Hashimoto, N.
2016-12-01
For the forthcoming Nankai earthquake with M8 to M9 class, the Earthquake Research Committee(ERC)/Headquarters for Earthquake Research Promotion, Japanese government (2013) showed 15 examples of earthquake source areas (ESAs) as possible combinations of 18 sub-regions (6 segments along trough and 3 segments normal to trough) and assessed the occurrence probability within the next 30 years (from Jan. 1, 2013) was 60% to 70%. Hirata et al.(2015, AGU) presented Probabilistic Tsunami Hazard Assessment (PTHA) along Nankai Trough in the case where diversity of the next event's ESA is modeled by only the 15 ESAs. In this study, we newly set 70 ESAs in addition of the previous 15 ESAs so that total of 85 ESAs are considered. By producing tens of faults models, with various slip distribution patterns, for each of 85 ESAs, we obtain 2500 fault models in addition of previous 1400 fault models so that total of 3900 fault models are considered to model the diversity of the next Nankai earthquake rupture (Toyama et al.,2015, JpGU). For PTHA, the occurrence probability of the next Nankai earthquake is distributed to possible 3900 fault models in the viewpoint of similarity to the 15 ESAs' extents (Abe et al.,2015, JpGU). A major concept of the occurrence probability distribution is; (i) earthquakes rupturing on any of 15 ESAs that ERC(2013) showed most likely occur, (ii) earthquakes rupturing on any of ESAs whose along-trench extent is the same as any of 15 ESAs but trough-normal extent differs from it second likely occur, (iii) earthquakes rupturing on any of ESAs whose both of along-trough and trough-normal extents differ from any of 15 ESAs rarely occur. Procedures for tsunami simulation and probabilistic tsunami hazard synthesis are the same as Hirata et al (2015). A tsunami hazard map, synthesized under an assumption that the Nankai earthquakes can be modeled as a renewal process based on BPT distribution with a mean recurrence interval of 88.2 years (ERC, 2013) and an aperiodicity of 0.22, as the median of the values (0.20 to 0.24)that ERC (2013) recommended, suggests that several coastal segments along the southwest coast of Shikoku Island, the southeast coast of Kii Peninsula, and the west coast of Izu Peninsula show over 26 % in exceedance probability that maximum water rise exceeds 10 meters at any coastal point within the next 30 years.
High H2O/Ce of K-rich MORB from Lena Trough and Gakkel Ridge, Arctic Ocean
NASA Astrophysics Data System (ADS)
Snow, J. E.; Feig, S. T.
2014-12-01
Lena Trough in the Arctic ocean is the oblique spreading continuation of Gakkel Ridge through the Fram Strait (eg Snow et al. 2011). Extreme trace element and isotopic compositions seen in Lena Trough basalt appear to be the enriched end member dominating the geochemistry of the Western Volcanic Zone of the Western Gakkel Ridge as traced by Pb isotopes, K2O/TiO2, Ba/Nb and other isotopic, major and trace element indicators of mixing (Nauret et al., 2011). This is in contrast to neighboring Gakkel Ridge which has been spreading for 50-60 million years. Basalts from Lena Trough also show a pure MORB noble gas signature (Nauret et al., 2010) and peridotites show no evidence of ancient components in their Os isotopes (Lassiter, et al., in press). The major and trace element compositions of the basalts, however are very distinct from MORB, being far more potassic than all but a single locality on the SW Indian Ridge. We determined H2O and trace element composiitions of a suite of 17 basalt glasses from the Central Lena Trough (CLT) and the Gakkel Western Volcanic Zone, including many of those previously analyzed by Nauret et al. (2012). The Western Gakkel glasses have high H2O/Ce for MORB (>300) suggesting a water rich source consistent with the idea that the northernmost Atlantic mantle is enriched in water (Michael et al., 1995). They are within the range of Eastern Gakkel host glasses determined by Wanless et al, 2013. The Lena Trough (CLT) glasses are very rich in water for MORB (>1% H2O) and are among the highest H2O/Ce (>400) ever measured in MORB aside from melt inclusions in olivine. Mantle melting dynamics and melt evolution cannot account for the H2O/Ce variations in MORB, as these elements have similar behavior during melting and crustal evolution. Interestingly, the H2O/K2O ratios in the basalts are only around 1. This is because the K2O levels in the CLT glasses are very high as well relative to REE. The absolutely linear relationship between H2O and K2O/TiO2 in Lena and Gakkel basalts shows that water systematics in these rocks are completely governed by source composition, with little or no modification by mantle melting dynamics or crystal fractionation. The geochemical influence of the WVZ enriched mantle source declines with distance from Lena Trough along Gakkel Ridge.
Technology and education: First approach for measuring temperature with Arduino
NASA Astrophysics Data System (ADS)
Carrillo, Alejandro
2017-04-01
This poster session presents some ideas and approaches to understand concepts of thermal equilibrium, temperature and heat in order to bulid a man-nature relationship in a harmonious and responsible manner, emphasizing the interaction between science and technology, without neglecting the relationship of the environment and society, an approach to sustainability. It is proposed the development of practices that involve the use of modern technology, of easy access and low cost to measure temperature. We believe that the Arduino microcontroller and some temperature sensors can open the doors of innovation to carry out such practices. In this work we present some results of simple practices presented to a population of students between the ages of 16 and 17 years old. The practices in this proposal are: Zero law of thermodynamics and the concept of temperature, calibration of thermometers and measurement of temperature for heating and cooling of three different substances under the same physical conditions. Finally the student is asked to make an application that involves measuring of temperature and other physical parameters. Some suggestions are: to determine the temperature at which we take some food, measure the temperature difference at different rooms of a house, housing constructions that favour optimal condition, measure the temperature of different regions, measure of temperature trough different colour filters, solar activity and UV, propose applications to understand current problems such as global warming, etc. It is concluded that the Arduino practices and electrical sensors increase the cultural horizon of the students while awaking their interest to understand their operation, basic physics and its application from a modern perspective.
Elevated Voriconazole Level Associated With Hallucinations and Suicidal Ideation: A Case Report.
Jansen, Jeffrey W; Sen, Sumon K; Moenster, Ryan P
2017-01-01
Voriconazole, a broad-spectrum antifungal, has been associated with visual and auditory hallucinations. We report the case of patient being treated with voriconazole for pulmonary aspergillosis who developed visual hallucinations and new suicidal ideation with plan. Voriconazole troughs were supratherapeutic (9.0 mcg/mL) and the patient was positive for the CYP2C19*1/*2 allele.
Concentrating Solar Power Projects - Xina Solar One | Concentrating Solar
Power | NREL Xina Solar One Abengoa has been selected by the Department of Energy (DOE) of South Africa to develop Xina Solar One, a 100 MW parabolic trough plant with a five-hour thermal energy with Abengoa's plant KaXu Solar One that is currently under construction in the country. Xina Solar One
Concentrating Solar Power Projects - Parabolic Trough Projects |
Project Godawari Solar Project Gujarat Solar One Gulang 100MW Thermal Oil Parabolic Trough project Guzmán Kuraymat (ISCC Kuraymat) Kathu Solar Park KaXu Solar One KVK Energy Solar Project La Africana La Dehesa La Power Facility Nevada Solar One (NSO) NOOR I NOOR II Olivenza 1 Orellana Palma del RÃo I Palma del RÃo
Central venous pulse pressure analysis using an R-synchronized pressure measurement system.
Fujita, Yoshihisa; Hayashi, Daisuke; Wada, Shinya; Yoshioka, Naoki; Yasukawa, Takeshi; Pestel, Gunther
2006-12-01
The information derived from central venous catheters is underused. We developed an EKG-R synchronization and averaging system to obtained distinct CVP waveforms and analyzed components of these. Twenty-five paralyzed surgical patients undergoing CVP monitoring under mechanical ventilation were studied. CVP and EKG signals were analyzed employing our system, the mean CVP and CVP at end-diastole during expiration were compared, and CVP waveform components were measured using this system. CVP waveforms were clearly visualized in all patients. They showed the a peak to be 1.8+/- 0.7 mmHg, which was the highest of three peaks, and the x trough to be lower than the y trough (-1.6+/- 0.7 mmHg and -0.9+/- 0.5 mmHg, respectively), with a mean pulse pressure of 3.4 mmHg. The difference between the mean CVP and CVP at end-diastole during expiration was 0.58+/- 0.81 mmHg. The mean CVP can be used as an index of right ventricular preload in patients under mechanical ventilation with regular sinus rhythm. Our newly developed system is useful for clinical monitoring and for education in circulatory physiology.
Methotrexate Reduced TNF Bioactivity in Rheumatoid Arthritis Patients Treated with Infliximab
Rinaudo-Gaujous, Mélanie; Thomas, Thierry
2017-01-01
Objectives. To evaluate methotrexate effect on tumor necrosis factor (TNF) alpha bioactivity during infliximab (IFX) therapy in rheumatoid arthritis (RA) patients and to correlate TNF bioactivity with antibody towards IFX (ATI) development and RA clinical response. Materials and Methods. Thirty-nine active women RA patients despite conventional synthetic disease modifying antirheumatic drugs (csDMARDs) requiring IFX therapy were enrolled, and clinical data and blood samples were recorded at baseline (W0) and at 6 weeks (W6), W22, and W54 of IFX treatment. TNF bioactivity as well as IFX trough and ATI concentrations were assessed on blood samples. Results. TNF bioactivity decreased from W0 to W54 with a large range from W22 at the time of ATI detection. From W22, TNF bioactivity was lower in presence of methotrexate as csDMARD compared to other csDMARDs. IFX trough concentration increased from W0 to W54 with a large range from W22, similarly to TNF bioactivity. Methotrexate therapy prevented ATI presence at W22 and reduced TNF bioactivity compared to other csDMARDs (p = 0.002). Conclusion. This suggests that methotrexate plays a key role in TNF bioactivity and against ATI development. PMID:28352145
Two-Dimensional Automatic Measurement for Nozzle Flow Distribution Using Improved Ultrasonic Sensor
Zhai, Changyuan; Zhao, Chunjiang; Wang, Xiu; Wang, Ning; Zou, Wei; Li, Wei
2015-01-01
Spray deposition and distribution are affected by many factors, one of which is nozzle flow distribution. A two-dimensional automatic measurement system, which consisted of a conveying unit, a system control unit, an ultrasonic sensor, and a deposition collecting dish, was designed and developed. The system could precisely move an ultrasonic sensor above a pesticide deposition collecting dish to measure the nozzle flow distribution. A sensor sleeve with a PVC tube was designed for the ultrasonic sensor to limit its beam angle in order to measure the liquid level in the small troughs. System performance tests were conducted to verify the designed functions and measurement accuracy. A commercial spray nozzle was also used to measure its flow distribution. The test results showed that the relative error on volume measurement was less than 7.27% when the liquid volume was 2 mL in trough, while the error was less than 4.52% when the liquid volume was 4 mL or more. The developed system was also used to evaluate the flow distribution of a commercial nozzle. It was able to provide the shape and the spraying width of the flow distribution accurately. PMID:26501288
Temporal variability of the Circumpolar Deep Water inflow onto the Ross Sea continental shelf
NASA Astrophysics Data System (ADS)
Castagno, Pasquale; Falco, Pierpaolo; Dinniman, Michael S.; Spezie, Giancarlo; Budillon, Giorgio
2017-02-01
The intrusion of Circumpolar Deep Water (CDW) is the primary source of heat, salt and nutrients onto Antarctica's continental shelves and plays a major role in the shelf physical and biological processes. Different studies have analyzed the processes responsible for the transport of CDW across the Ross Sea shelf break, but until now, there are no continuous observations that investigate the timing of the intrusions. Also, few works have focused on the effect of the tides that control these intrusions. In the Ross Sea, the CDW intrudes onto the shelf in several locations, but mostly along the troughs. We use hydrographic observations and a mooring placed on the outer shelf in the middle of the Drygalski Trough in order to characterize the spatial and temporal variability of CDW inflow onto the shelf. Our data span from 2004 to the beginning of 2014. In the Drygalski Trough, the CDW enters as a 150 m thick layer between 250 and 400 m, and moves upward towards the south. At the mooring location, about 50 km from the shelf break, two main CDW cores can be observed: one on the east side of the trough spreading along the west slope of Mawson Bank from about 200 m to the bottom and the other one in the central-west side from 200 m to about 350 m depth. A signature of this lighter and relatively warm water is detected by the instruments on the mooring at bottom of the Drygalski Trough. High frequency periodic CDW intrusion at the bottom of the trough is related to the diurnal and spring/neap tidal cycles. At lower frequency, a seasonal variability of the CDW intrusion is noticed. A strong inflow of CDW is observed every year at the end of December, while the CDW inflow is at its seasonal minimum during the beginning of the austral fall. In addition an interannual variability is also evident. A change of the CDW intrusion before and after 2010 is observed.
Palaeo-ice stream pathways in the easternmost Amundsen Sea Embayment, West Antarctica
NASA Astrophysics Data System (ADS)
Klages, Johann P.; Kuhn, Gerhard; Graham, Alastair G. C.; Smith, James A.; Hillenbrand, Claus-Dieter; Nitsche, Frank O.; Larter, Rob D.; Gohl, Karsten
2015-04-01
Multibeam swath bathymetry datasets collected over the past two decades have been compiled to identify palaeo-ice stream pathways in the easternmost Amundsen Sea Embayment. We mapped 3010 glacial landforms to reconstruct palaeo-ice flow in the ~250 km-long Abbot Glacial Trough that was occupied by a large palaeo-ice stream, fed by two tributaries (Cosgrove and Abbot) that reached the continental shelf edge during the last maximum ice-sheet advance. The mapping has enabled a clear differentiation between glacial landforms interpreted as indicative of wet- (e.g. mega-scale glacial lineations) and cold-based ice (e.g. hill-hole pairs) during the last glaciation of the continental shelf. Both the regions of fast palaeo-ice flow within the palaeo-ice stream troughs, and the regions of slow palaeo-ice flow on adjacent seafloor highs (referred to as inter-ice stream ridges) additionally record glacial landforms such as grounding-zone wedges and recessional moraines that indicate grounding line stillstands of the ice sheet during the last deglaciation from the shelf. As the palaeo-ice stream flowed along a trough with variable geometry and variable subglacial substrate, it appears that trough sections characterized by constrictions and outcropping hard substrate that changes the bed gradient, led the pace of grounding-line retreat to slow and subsequently pause, resulting in the deposition of grounding-zone wedges. The stepped retreat recorded within the Abbot Glacial Trough corresponds well to post-glacial stepped retreat interpreted for the neighbouring Pine Island-Thwaites Palaeo-Ice Stream trough, thus suggesting a uniform pattern of episodic retreat across the eastern Amundsen Sea Embayment. The correlation of episodic retreat features with geological boundaries further emphasises the significance of subglacial geology in steering ice stream flow. Our new geomorphological map of the easternmost Amundsen Sea Embayment resolves the pathways of palaeo-ice streams that were probably all active during the last maximum extent of the ice sheet on this part of the shelf, and reveals the style of postglacial grounding-line retreat. Both are important input variables in ice sheet models and therefore can be used for validating the reliability of these models.
An empirical determination of the effects of sea state bias on Seasat altimetry
NASA Technical Reports Server (NTRS)
Born, G. H.; Richards, M. A.; Rosborough, G. W.
1982-01-01
A linear empirical model has been developed for the correction of sea state bias effects, in Seasat altimetry data altitude measurements, that are due to (1) electromagnetic bias caused by the fact that ocean wave troughs reflect the altimeter signal more strongly than the crests, shifting the apparent mean sea level toward the wave troughs, and (2) an independent instrument-related bias resulting from the inability of height corrections applied in the ground processor to compensate for simplifying assumptions made for the processor aboard Seasat. After applying appropriate corrections to the altimetry data, an empirical model for the sea state bias is obtained by differencing significant wave height and height measurements from coincident ground tracks. Height differences are minimized by solving for the coefficient of a linear relationship between height differences and wave height differences that minimize the height differences. In more than 50% of the 36 cases examined, 7% of the value of significant wave height should be subtracted for sea state bias correction.
Climatology of atmospheric circulation patterns of Arabian dust in western Iran.
Najafi, Mohammad Saeed; Sarraf, B S; Zarrin, A; Rasouli, A A
2017-08-28
Being in vicinity of vast deserts, the west and southwest of Iran are characterized by high levels of dust events, which have adverse consequences on human health, ecosystems, and environment. Using ground based dataset of dust events in western Iran and NCEP/NCAR reanalysis data, the atmospheric circulation patterns of dust events in the Arabian region and west of Iran are identified. The atmospheric circulation patterns which lead to dust events in the Arabian region and western Iran were classified into two main categories: the Shamal dust events that occurs in warm period of year and the frontal dust events as cold period pattern. In frontal dust events, the western trough or blocking pattern at mid-level leads to frontogenesis, instability, and air uplift at lower levels of troposphere in the southwest of Asia. Non-frontal is other pattern of dust event in the cold period and dust generation are due to the regional circulation systems at the lower level of troposphere. In Shamal wind pattern, the Saudi Arabian anticyclone, Turkmenistan anticyclone, and Zagros thermal low play the key roles in formation of this pattern. Summer and transitional patterns are two sub-categories of summer Shamal wind pattern. In summer trough pattern, the mid-tropospheric trough leads to intensify the surface thermal systems in the Middle East and causes instability and rising of wind speed in the region. In synthetic pattern of Shamal wind and summer trough, dust is created by the impact of a trough in mid-levels of troposphere as well as existing the mentioned regional systems which are contributed in formation of summer Shamal wind pattern.
Morphology and sedimentology of glacigenic submarine fans on the west Greenland continental margin
NASA Astrophysics Data System (ADS)
O'Cofaigh, Colm; Hogan, Kelly A.; Dowdeswell, Julian A.; Jennings, Anne E.; Noormets, Riko; Evans, Jeffrey
2014-05-01
Along the West Greenland continental margin adjoining Baffin Bay, bathymetric data show a series of large submarine fans located at the mouths of cross-shelf troughs. Two of these fans, the Uummannaq Fan and the Disko Fan are trough-mouth fans built largely of debris delivered from ice sheet outlets of the Greenland Ice Sheet during past glacial maxima. On the Uummannaq Fan glacigenic debris flow deposits occur on the upper slope and extend to at least 1800 m water depth in front of the trough-mouth. The debris flow deposits are related to the remobilisation of subglacial debris that was delivered onto the upper slope at times when an ice stream was positioned at the shelf edge. In contrast, sedimentary facies from the northern sector of the fan are characterised by hemipelagic and ice-rafted sediments and turbidites; glacigenic debris flows are notably absent in cores from this region. Further south along the Greenland continental margin the surface of the Disko Fan is prominently channelised and associated sediments are acoustically stratified. Although glacigenic debris flow deposits do occur on the upper Disko Fan, sediments recovered in cores from elsewhere on the fan record the influence of turbidity current and meltwater sedimentation. The channelised form of the Disko fan contrasts markedly with that of the Uummannaq Fan and, more widely, with trough mouth fans from the Polar North Atlantic. Collectively these data highlight the variability of glacimarine depositional processes operating on trough-mouth fans on high-latitude continental slopes and show that glacigenic debris flows are but one of a number of mechanisms by which such large glacially-influenced depocentres form.
de la Loge, Christine; Tugaut, Béatrice; Fofana, Fatoumata; Lambert, Jérémy; Hennig, Michael; Tschiesner, Uta; Vahdati-Bolouri, Mitra; Segun Ismaila, Afisi; Suresh Punekar, Yogesh
2016-03-15
Background: This meta-analysis assessed the relationship between change from baseline (CFB) in spirometric measurements (trough forced expiratory volume in 1 second [FEV 1 ] and FEV 1 area under the curve [AUC]) and patient-reported outcomes (St. George's Respiratory Questionnaire total score [SGRQ] CFB, Transition Dyspnea Index [TDI] and exacerbation rates) after 6-12 months' follow-up, using study treatment-group level data. Methods: A systematic literature search was performed for randomized controlled trials of ≥24 weeks duration in adults with chronic obstructive pulmonary disease (COPD). Studies reporting ≥1 spirometric measurement and ≥1 patient-reported outcome (PRO) at baseline and at study endpoint were selected. The relationships between PROs and spirometric endpoints were assessed using Pearson correlation coefficient and meta-regression. Results: Fifty-two studies (62,385 patients) were included. Primary weighted analysis conducted at the last assessment showed a large significant negative correlation (r, -0.68 [95% confidence interval (CI); -0.77, -0.57]) between trough FEV 1 and SGRQ. Improvement of 100 mL in trough FEV 1 corresponded to a 5.9 point reduction in SGRQ. Similarly, a reduction of 4 points on SGRQ corresponded to 40 mL improvement in trough FEV 1 ( p <0.001). The weighted correlation coefficients of trough FEV 1 with TDI, exacerbation rate (all) and exacerbation rate (moderate/severe) at last assessment point were 0.57, -0.69 and -0.57, respectively (all p <0.05). For the analyses excluding placebo groups, the correlations of FEV 1 with SGRQ and TDI were lower but significant. Conclusions: A strong association exists between changes in spirometric measurements and changes in PROs.
Burkhauser, R V; Cutts, A C; Lillard, D R
1999-09-01
The goal of the study was to show that cross-sectional and longitudinal data yield dramatically different answers to a basic question: "How did older persons fare in the recovery years of the 1980s?" The United States Panel Study of Income Dynamics and the German Socio-Economic Panel are used cross-sectionally to capture changes in the economic well-being of older persons in the trough and peak years of the 1980s business cycle, and longitudinally to trace how the economic well-being of a given cohort of older persons changed over those years. Kernel density estimation is then used to show how the distribution of economic well-being of these populations changed over these years. Cross-sectional comparisons confirm that persons aged 65 and over in the peak year were better off than persons aged 65 and over in the trough year in both countries. Longitudinal comparisons, however, show that persons aged 65 and over in the trough year who survived to the peak year received a substantially smaller share of the rewards of economic recovery than cross-sectional comparisons imply. Moreover, the entire income distribution of older persons in the United States shifted downwards. Compositional changes in the cross-sectional data, caused by the entry of high-income persons who are young in the peak year but old in the trough year, obscure the decline in the economic well-being of the cohort of older persons who survived the trough year, in cross-sectional comparisons of older populations in the United States in the 1980s.
On Local Ionization Equilibrium and Disk Winds in QSOs
NASA Astrophysics Data System (ADS)
Pereyra, Nicolas A.
2014-11-01
We present theoretical C IV λλ1548,1550 absorption line profiles for QSOs calculated assuming the accretion disk wind (ADW) scenario. The results suggest that the multiple absorption troughs seen in many QSOs may be due to the discontinuities in the ion balance of the wind (caused by X-rays), rather than discontinuities in the density/velocity structure. The profiles are calculated from a 2.5-dimensional time-dependent hydrodynamic simulation of a line-driven disk wind for a typical QSO black hole mass, a typical QSO luminosity, and for a standard Shakura-Sunyaev disk. We include the effects of ionizing X-rays originating from within the inner disk radius by assuming that the wind is shielded from the X-rays from a certain viewing angle up to 90° ("edge on"). In the shielded region, we assume constant ionization equilibrium, and thus constant line-force parameters. In the non-shielded region, we assume that both the line-force and the C IV populations are nonexistent. The model can account for P-Cygni absorption troughs (produced at edge on viewing angles), multiple absorption troughs (produced at viewing angles close to the angle that separates the shielded region and the non-shielded region), and for detached absorption troughs (produced at an angle in between the first two absorption line types); that is, the model can account for the general types of broad absorption lines seen in QSOs as a viewing angle effect. The steady nature of ADWs, in turn, may account for the steady nature of the absorption structure observed in multiple-trough broad absorption line QSOs. The model parameters are M bh = 109 M ⊙ and L disk = 1047 erg s-1.
Nationwide conversion to generic tacrolimus in pediatric kidney transplant recipients.
Naicker, Derisha; Reed, Peter W; Ronaldson, Jane; Kara, Tonya; Wong, William; Prestidge, Chanel
2017-11-01
Bioequivalence between Tacrolimus Prograf® and generic tacrolimus formulations has been demonstrated in adult populations, however clinical experience and safety data regarding generic tacrolimus in pediatric transplant recipients is limited. This study aimed to evaluate conversion from Tacrolimus Prograf® to Sandoz® in pediatric renal transplant recipients nationwide. The primary outcome was a change in mean trough tacrolimus concentration. Additionally, changes in tacrolimus intra-patient coefficient of variation (CoV), allograft function, requirement for dose adjustments, and episodes of biopsy-proven rejection were evaluated. Retrospective cohort study in 37 pediatric renal transplant recipients who switched to Tacrolimus Sandoz®. Each patient had three pre-conversion tacrolimus trough and creatinine concentrations within the 4 months prior and three post-conversion concentrations on day 3, 10, and the next subsequent level. Mean pre- and post-conversion tacrolimus trough concentrations and glomerular filtration rate (eGFR) were calculated. Tacrolimus concentration, CoV, and creatinine differences were compared by paired t test. Thirty-seven patients (41% females, age 3-18 years) were included. Average intra-patient difference in trough tacrolimus concentration was 0.05μg/l (95% CI -0.37 to 0.47). Average intra-patient difference in eGFR was -1.20 ml/min/1.73 2 (95% CI -3.53 to 1.13). Three patients had acute rejection during 12 months post-conversion compared to none during 12 months pre-conversion. Pediatric renal transplant recipients can be converted from Tacrolimus Prograf® to Sandoz® with negligible change in trough concentration, dose adjustments, or immediate allograft function. Of concern was the number of acute rejection episodes, however non-adherence contributed to at least one episode and this difference was determined clinically and statistically not significant.
NASA Astrophysics Data System (ADS)
Byrnes, J. S.; Bezada, M.
2017-12-01
Melt can be retained in the mantle at triple junctions between grain boundaries, be spread in thin films along two-grain boundaries, or be organized by shear into elongate melt-rich bands. Which of these geometries is most prevalent is unknown. This ambiguity makes the interpretation of anomalous seismic velocities and quality factors difficult, since different geometries would result in different mechanical effects. Here, we compare observations of seismic attenuation beneath the Salton Trough and the Snake River Plain; two regions where the presence of melt has been inferred. The results suggest that seismic attenuation is diagnostic of melt geometry. We measure the relative attenuation of P waves from deep focus earthquakes using a time-domain method. Even though the two regions are underlain by comparably strong low-velocity anomalies, their attenuation signature is very different. The upper mantle beneath the Salton Trough is sufficiently attenuating that the presence of melt must lower Qp, while attenuation beneath the Snake River Plain is not anomalous with respect to surrounding regions. These seemingly contradictory results can be reconciled if different melt geometries characterize each region. SKS splitting from the Salton Trough suggests that melt is organized into melt-rich bands, while this is not the case for the Snake River Plain. We infer that beneath the Snake River Plain melt is retained at triple junctions between grain boundaries, a geometry that is not predicted to cause seismic attenuation. More elongate geometries beneath the Salton Trough may cause seismic attenuation via the melt-squirt mechanism. In light of these results, we conclude that prior observations of low seismic velocities with somewhat high quality factors beneath the East Pacific Rise and Southern California suggest that melt does not organize into elongate bands across much of the asthenosphere.
de la Loge, Christine; Tugaut, Béatrice; Fofana, Fatoumata; Lambert, Jérémy; Hennig, Michael; Tschiesner, Uta; Vahdati-Bolouri, Mitra; Segun Ismaila, Afisi; Suresh Punekar, Yogesh
2016-01-01
Background: This meta-analysis assessed the relationship between change from baseline (CFB) in spirometric measurements (trough forced expiratory volume in 1 second [FEV1] and FEV1 area under the curve [AUC]) and patient-reported outcomes (St. George’s Respiratory Questionnaire total score [SGRQ] CFB, Transition Dyspnea Index [TDI] and exacerbation rates) after 6-12 months’ follow-up, using study treatment-group level data. Methods: A systematic literature search was performed for randomized controlled trials of ≥24 weeks duration in adults with chronic obstructive pulmonary disease (COPD). Studies reporting ≥1 spirometric measurement and ≥1 patient-reported outcome (PRO) at baseline and at study endpoint were selected. The relationships between PROs and spirometric endpoints were assessed using Pearson correlation coefficient and meta-regression. Results: Fifty-two studies (62,385 patients) were included. Primary weighted analysis conducted at the last assessment showed a large significant negative correlation (r, −0.68 [95% confidence interval (CI); −0.77, −0.57]) between trough FEV1 and SGRQ. Improvement of 100 mL in trough FEV1 corresponded to a 5.9 point reduction in SGRQ. Similarly, a reduction of 4 points on SGRQ corresponded to 40 mL improvement in trough FEV1 (p<0.001). The weighted correlation coefficients of trough FEV1 with TDI, exacerbation rate (all) and exacerbation rate (moderate/severe) at last assessment point were 0.57, -0.69 and -0.57, respectively (all p<0.05). For the analyses excluding placebo groups, the correlations of FEV1 with SGRQ and TDI were lower but significant. Conclusions: A strong association exists between changes in spirometric measurements and changes in PROs. PMID:28848877
The nature of the crust under Cayman Trough from gravity
ten Brink, Uri S.; Coleman, D.F.; Dillon, William P.
2002-01-01
Considerable crustal thickness variations are inferred along Cayman Trough, a slow-spreading ocean basin in the Caribbean Sea, from modeling of the gravity field. The crust to a distance of 50 km from the spreading center is only 2–3 km thick in agreement with dredge and dive results. Crustal thickness increases to ∼5.5 km at distances between 100 and 430 km west of the spreading center and to 3.5–6 km at distances between 60 and 370 km east of the spreading center. The increase in thickness is interpreted to represent serpentinization of the uppermost mantle lithosphere, rather than a true increase in the volume of accreted ocean crust. Serpentinized peridotite rocks have indeed been dredged from the base of escarpments of oceanic crust rocks in Cayman Trough. Laboratory-measured density and P-wave speed of peridotite with 40–50% serpentine are similar to the observed speed in published refraction results and to the inferred density from the model. Crustal thickness gradually increases to 7–8 km at the far ends of the trough partially in areas where sea floor magnetic anomalies were identified. Basement depth becomes gradually shallower starting 250 km west of the rise and 340 km east of the rise, in contrast to the predicted trend of increasing depth to basement from cooling models of the oceanic lithosphere. The gradual increase in apparent crustal thickness and the shallowing trend of basement depth are interpreted to indicate that the deep distal parts of Cayman Trough are underlain by highly attenuated crust, not by a continuously accreted oceanic crust.
Kario, Kazuomi; Enya, Kazuaki; Sugiura, Kenkichi; Ikeda, Yoshinori
2014-01-01
Morning blood pressure (BP) surge is reported as a risk factor for cardiovascular events and end-organ damage independent of the 24-h BP level. Controlling morning BP surge is therefore important to help prevent onset of cardiovascular disease. We compared the efficacy of azilsartan and candesartan in controlling morning systolic BP (SBP) surges by analyzing relevant ambulatory BP monitoring data in patients with/without baseline BP surges. As part of a 16-week randomized, double-blind study of azilsartan (20–40 mg once daily) and candesartan (8–12 mg once daily) in Japanese patients with essential hypertension, an exploratory analysis was carried out using ambulatory BP monitoring at baseline and week 14. The effects of study drugs on morning BP surges, including sleep trough surge (early morning SBP minus the lowest night-time SBP) and prewaking surge (early morning SBP minus SBP before awakening), were evaluated. Patients with sleep trough surge of at least 35 mmHg were defined by the presence of a morning BP surge (the ‘surge group’). Sleep trough surge and prewaking surge data were available at both baseline and week 14 in 548 patients, 147 of whom (azilsartan 76; candesartan 71) had a baseline morning BP surge. In surge group patients, azilsartan significantly reduced both the sleep trough surge and the prewaking surge at week 14 compared with candesartan (least squares means of the between-group differences −5.8 mmHg, P=0.0395; and −5.7 mmHg, P=0.0228, respectively). Once-daily azilsartan improved sleep trough surge and prewaking surge to a greater extent than candesartan in Japanese patients with grade I–II essential hypertension. PMID:24710336
Rakugi, Hiromi; Kario, Kazuomi; Enya, Kazuaki; Sugiura, Kenkichi; Ikeda, Yoshinori
2014-06-01
Morning blood pressure (BP) surge is reported as a risk factor for cardiovascular events and end-organ damage independent of the 24-h BP level. Controlling morning BP surge is therefore important to help prevent onset of cardiovascular disease. We compared the efficacy of azilsartan and candesartan in controlling morning systolic BP (SBP) surges by analyzing relevant ambulatory BP monitoring data in patients with/without baseline BP surges. As part of a 16-week randomized, double-blind study of azilsartan (20-40 mg once daily) and candesartan (8-12 mg once daily) in Japanese patients with essential hypertension, an exploratory analysis was carried out using ambulatory BP monitoring at baseline and week 14. The effects of study drugs on morning BP surges, including sleep trough surge (early morning SBP minus the lowest night-time SBP) and prewaking surge (early morning SBP minus SBP before awakening), were evaluated. Patients with sleep trough surge of at least 35 mmHg were defined by the presence of a morning BP surge (the 'surge group'). Sleep trough surge and prewaking surge data were available at both baseline and week 14 in 548 patients, 147 of whom (azilsartan 76; candesartan 71) had a baseline morning BP surge. In surge group patients, azilsartan significantly reduced both the sleep trough surge and the prewaking surge at week 14 compared with candesartan (least squares means of the between-group differences -5.8 mmHg, P=0.0395; and -5.7 mmHg, P=0.0228, respectively). Once-daily azilsartan improved sleep trough surge and prewaking surge to a greater extent than candesartan in Japanese patients with grade I-II essential hypertension.
Evaluation of risk factors for vancomycin-induced nephrotoxicity.
Park, So Jin; Lim, Na Ri; Park, Hyo Jung; Yang, Jae Wook; Kim, Min-Ji; Kim, Kyunga; In, Yong Won; Lee, Young Mee
2018-05-09
Background Vancomycin is a glycopeptide antibiotic of choice for the treatment of serious infections caused by multi-resistant Gram-positive bacteria. However, vancomycin-associated nephrotoxicity (VAN) often limits its use. Previous data suggested a few risk factors of VAN, including higher mean vancomycin trough level, higher daily doses, old age, long duration of vancomycin therapy, and concomitant nephrotoxins. Objective To evaluate the incidence and risk factors of VAN and determine whether higher vancomycin trough concentrations were associated with a greater risk for VAN. Settings A retrospective, observational, single-center study at the 1960-bed university-affiliated tertiary care hospital (Samsung Medical Center), Seoul, Korea. Method A retrospective analysis of adult patients who received vancomycin parenterally in a tertiary care medical center from March 1, 2013 to June 30, 2013 was performed. We excluded patients with a baseline serum creatinine level > 2 mg/dL and those who had a history of end-stage renal disease and dialysis at baseline. The clinical characteristics were compared between patients with nephrotoxicity and those without nephrotoxicity to identify the risk factors associated with VAN. Main outcome measure Incidence of VAN and VAN-associated risk factors were analyzed. Results Of the 315 vancomycin-treated patients, nephrotoxicity occurred in 15.2% of the patients. In multivariate analysis, higher vancomycin trough concentrations of > 20 mg∕L (OR 9.57, 95% CI 2.49-36.83, p < 0.01) and intensive care unit (ICU) residence (OR 2.86, 95% CI 1.41-5.82, p < 0.01) were independently associated with VAN. Conclusion Our findings suggest that higher vancomycin trough levels and ICU residence might be associated with a greater risk for VAN. More careful monitoring of vancomycin serum trough levels and patient status might facilitate the timely prevention of VAN.
Heat Loss Testing of Schott's 2008 PTR70 Parabolic Trough Receiver
DOE Office of Scientific and Technical Information (OSTI.GOV)
Burkholder, Frank; Kutscher, Chuck
2009-05-01
Two Schott 2008 model year PTR70 HCEs were tested on NREL's heat loss test stand from 100 - 500 deg C in 50 deg C increments. Absorber emittance was determined from the laboratory testing so that the performance of the HCEs could be modeled in a parabolic trough collector. Collector/HCE simulation results for many different field operation conditions were used to create heat loss correlationcoefficients for Excelergy and SAM. SAM estimates that the decreased emittance of the 2008 PTR70 will decrease the LCOE for parabolic trough power plants by 0.5 cents/kWh and increase the electricity generated by 5% relative tomore » previous PTR70s. These conclusions assume that the 2008 PTR70 is supplied at the same cost and with the same optical performance as earlier PTR70 models.« less
Gibson, D.L.
2000-01-01
Previously undated post-Devonian sediments outcropping north of Fowlers Gap station near the western margin of the Bancannia Trough are shown by plant macro- and microfossil determinations to be of Early Cretaceous (most likely Neocomian and/or Aptian) age, and thus part of the Eromanga Basin. They are assigned to the previously defined Telephone Creek Formation. Study of the structural configuration of this unit and the unconformably underlying Devonian rocks suggests that the gross landscape architecture of the area results from post-Early Cretaceous monoclinal folding along blind faults at the western margin of the trough, combined with the effects of differential erosion. This study shows that, while landscape evolution in the area has been dynamic, the major changes that have occurred are on a geological rather than human timescale.
Element of an inductive coupler
Hall, David R.; Fox, Joe
2006-08-15
An element for an inductive coupler in a downhole component comprises magnetically conductive material, which is disposed in a recess in annular housing. The magnetically conductive material forms a generally circular trough. The circular trough comprises an outer generally U-shaped surface, an inner generally U-shaped surface, and two generally planar surfaces joining the inner and outer surfaces. The element further comprises pressure relief grooves in at least one of the surfaces of the circular trough. The pressure relief grooves may be scored lines. Preferably the pressure relief grooves are parallel to the magnetic field generated by the magnetically conductive material. The magnetically conductive material is selected from the group consisting of soft iron, ferrite, a nickel iron alloy, a silicon iron alloy, a cobalt iron alloy, and a mu-metal. Preferably, the annular housing is a metal ring.
NASA Astrophysics Data System (ADS)
Kitada, K.; Kasaya, T.; Iwamoto, H.; Nogi, Y.
2017-12-01
The Okinawa Trough is an active back-arc basin formed by the rifting associated with extension of the continental margin behind the Ryukyu trench. New hydrothermal sites were recently discovered off Kumejima Island in the Mid-Okinawa Trough and the hydrothermal mineral deposits were identified by seafloor surveys and rock samplings by ROV (e.g., JOGMEC, 2015). In order to characterize the sub-seafloor structures and the spatial distribution of the magmatic activity around the sites, we conducted the dense magnetic, gravity and bathymetric surveys with a line spacing of 0.5 nmi aboard the R/Vs Yokosuka and Kairei, operated by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) in 2016. The geophysical data collected during the previous cruises in the area by JAMSTEC were additionally used for this study. Magnetic anomaly was calculated by subtracting the IGRF model and the magnetization intensity was estimated by the method of Parker and Huestis (1974). Free-air gravity anomaly was calculated with subtracting the normal gravity field and with corrections of the drift and of the Eötvös effect. Bouguer gravity anomaly was calculated based on the method of Parker (1972). The magnetization intensity and the Bouguer gravity anomaly reveal three characteristics of the hydrothermal area off Kumejima Island: 1) The distribution of magnetization around the hydrothermal sites shows two different types of sub-seafloor magnetic features. One is corresponded to the submarine knolls with a relatively high magnetization of 4 A/M. The other is an ENE-WSW trending magnetization distribution with relatively high and low intensities, which is consistent with the trend of the bathymetric lineament. These features are considered to be formed by magmatism associated with submarine volcanoes and back-arc rifting. 2) The reduced magnetization zone corresponding to the hydrothermal area probably attributes to hydrothermal alteration of the host rock. 3) The hydrothermal site is located on the area where the Bouguer gravity anomaly is steeply changed from 10 to 30 mGal, suggesting that the hydrothermal activity can be related to the change in crustal thickness associated with back-arc rifting.
Prominent reflector beneath around the segmentation boundary between Tonankai-Nankai earthquake area
NASA Astrophysics Data System (ADS)
Nakanishi, A.; Shimomura, N.; Fujie, G.; Kodaira, S.; Obana, K.; Takahashi, T.; Yamamoto, Y.; Yamashita, M.; Takahashi, N.; Kaneda, Y.; Mochizuki, K.; Kato, A.; Iidaka, T.; Kurashimo, E.; Shinohara, M.; Takeda, T.; Shiomi, K.
2013-12-01
In the Nankai Trough subduction seismogenic zone, the Nankai and Tonankai earthquakes had often occurred simultaneously, and caused a great event. In most cases, first break of such large events of Nankai Trough usually begins from southwest off the Kii Peninsula so far. The idea of split Philippine Sea plate between the Kii Peninsula and the Shikoku Island, which explains seismicity, tectonic background, receiver function image and historical plate motion, was previously suggested. Moreover, between the Kii Peninsula and the Shikoku Island, there is a gap of deep low-frequency events observed in the belt-like zone along the strike of the subducting Philippine Sea plate. In 2010 and 2011, we conducted the large-scale high-resolution wide-angle and reflection (MCS) seismic study, and long-term observation from off Shikoku and Kii Peninsula. Marine active source seismic data have been acquired along grid two-dimensional profiles having the total length of ~800km/year. A three-dimensional seismic tomography using active and passive seismic data observed both land and ocean bottom stations have been also performed. From those data, we found a possible prominent reflector imaged in the offshore side in the Kii channel at the depth of ~18km. The velocity just beneath the reflector cannot be determined due to the lack of ray paths. Based of the amplitude information, we interpret the reflector as the forearc Moho based on the velocity gap (from ~6.4km/s to ~7.4km/s). However, the reflector is shallower than the forearc Moho of other area along the Nankai Trough. Similar reflectors are recognized along other seismic profiles around the Kii channel. In this presentation, we will show the result of structure analysis to understand the peculiar structure including the prominent reflector around the Kii channel. Relation between the structure and the existence of the segmentation of the Nankai megathrust earthquake or seismic gap of the deep low-frequency events will be also discussed. This study is part of 'Research concerning Interaction Between the Tokai, Tonankai and Nankai Earthquakes' funded by Ministry of Education, Culture, Sports, Science and Technology, Japan.
Modulations of Driven Nonlinear Surface Waves on Water and Liquid Helium-4.
1985-06-01
loop to control drive amplitude. 63 CHAPTER III. DATA AND INTERPRETATION. Section 5. Cockscombs. 25. Cockscomb in water at f/30. 67 26. Double...annular trough, sealed and then partially filled with normal or superfluid helium, is oscillated vertically and supported 6 . . ... . . . . . 41 700...44 0 .0 0 00 loudspeaker surface wave sealed trough transducer shel oo •Figure 3. Schmatic of the helium experiment. 8 r
Current status of the western gray squirrel population in the Puget Trough, Washington.
R. Bayrakci; A.B. Carey; T.M. Wilson
2001-01-01
The Puget Trough population of Washingtonâs state-threatened western gray squirrel is centered in Oregon white oak ecotones adjacent to conifer forests and prairies on the Fort Lewis Military Reservation. Our goal was to determine the current status of western gray squirrels in this region. In 1998, we found five western gray squirrels in 538 hours of foot surveys in...
NASA Astrophysics Data System (ADS)
Ishii, T.
2015-12-01
The Pacific plate is surrounded by circum-Pacific active margin, along which volcanic and seismic activities are very high. Ultra-Mega-Earthquakes (=UMEs, M>9.0) are occasionally observed along the margin, where sedimentary rocks of subducting slaves contact with the accreted sedimentary rocks of subducted slaves. But, those UME have never been occured along western Pacific islandarc-trench system including Izu-Ogasawara (=Bonin)-Mariana-Yap-Palau-Philippine-Tonga-Kermadec Trenches. I assume that the geological and petrological characteristics of the subduction boundaries are very important to understand those different seismic activities. Along the above mentioned trench inner wall, especially in the southern Mariana, mantle peridotites are widely distributed. Subducting slave contacts directly with the olivine dominant mantle peridotites of subducted slave, serpentinite layer can be deposited easily under hydrous oceanic sub-bottom environment and very slippery subduction boundaries are left along the subduction zone.On the other hand, those geological evidences give us some ideas on how to avoid UMEs in the Japanese Islands along Japan Trench and Nankai Trough in future. We will be able to change artificially from normal subduction boundaries with asperity zone into slippery subduction boundaries with serpentine layer, by means of serpentine mud injection toward the subduction boundaries interior by combining the following improved drilling technologies A and B. (A) Deep Sea Drilling Vessel CHIKYU has a drilling ability to reach subduction boundary with asperity zone in the Nankai Trough. (B) Advanced drilling technology in the shale gas industry is tremendous, that is, after one vertical deep drilling, horizontal drilling towards several direction are performed, then shale gas is collected by hydraulic fracturing method. I hope that, after several generations, our posterity will be able to avoid UMEs by continuous serpentine mud injection.
Microbial Community in the Hydrothermal System at Southern Mariana Trough
NASA Astrophysics Data System (ADS)
Kato, S.; Itahashi, S.; Kakegawa, T.; Utsumi, M.; Maruyama, A.; Ishibashi, J.; Marumo, K.; Urabe, T.; Yamagishi, A.
2004-12-01
There is unique ecosystem around deep-sea hydrothermal area. Living organisms are supported by chemical free energy provided by the hydrothermal water. The ecosystem is expected to be similar to those in early stage of life history on the earth, when photosynthetic organisms have not emerged. In this study, we have analyzed the microbial diversity in the hydrothermal area at southern Mariana trough. In the "Archaean Park Project" supported by special Coordination Fund, four holes were bored and cased by titanium pipes near hydrothermal vents in the southern Mariana trough in 2004. Hydrothermal fluids were collected from these cased holes and natural vents in this area. Microbial cells were collected by filtering the hydrothermal fluid in situ or in the mother sip. Filters were stored at -80C and used for DNA extraction. Chimneys at this area was also collected and stored at -80C. The filters and chimney samples were crushed and DNA was extracted. DNA samples were used for amplification of 16S rDNA fragments by PCR using archaea specific primers and universal primers. The PCR fragments were cloned and sequenced. These PCR clones of different samples will be compared. We will extend our knowledge about microbiological diversity at Southern Mariana trough to compare the results obtained at other area.
Inductive coupler for downhole components and method for making same
Hall, David R.; Hall, Jr., H. Tracy; Pixton, David S.; Dahlgren, Scott; Briscoe, Michael A.; Sneddon, Cameron; Fox, Joe
2006-05-09
The present invention includes a method of making an inductive coupler for downhole components. The method includes providing an annular housing, preferably made of steel, the housing having a recess. A conductor, preferably an insulated wire, is also provided along with a plurality of generally U-shaped magnetically conducting, electrically insulating (MCEI) segments. Preferably, the MCEI segments comprise ferrite. An assembly is formed by placing the plurality of MCEI segments within the recess in the annular housing. The segments are aligned to form a generally circular trough. A first portion of the conductor is placed within the circular trough. This assembly is consolidated with a meltable polymer which fills spaces between the segments, annular housing and the first portion of the conductor. The invention also includes an inductive coupler including an annular housing having a recess defined by a bottom portion and two opposing side wall portions. At least one side wall portion includes a lip extending toward but not reaching the other side wall portion. A plurality of generally U-shaped MCEI segments, preferably comprised of ferrite, are disposed in the recess and aligned so as to form a circular trough. The coupler further includes a conductor disposed within the circular trough and a polymer filling spaces between the segments, the annular housing and the conductor.
Depositional evolution of the Melville Bay trough-mouth fan, NW Greenland
NASA Astrophysics Data System (ADS)
Knutz, Paul; Gregersen, Ulrik
2015-04-01
The continental margin of NW Greenland bordering northern Baffin Bay is characterized by major sediment accumulations, known as Trough-Mouth Fans (TMF). The fan depocentres represent intense sediment dispersal at the terminus of ice streams that during cold climate periods provided major drainage routes of the northern Greenland Ice Sheet into Baffin Bay. The imprint of paleo-icestreams is seen by erosional troughs crossing a >250 km broad shelf region, which caps a series of sedimentary basins containing thick Mesozoic-Tertiary strata packages. This presentation provides an overview of the seismic stratigraphic division, depositional architecture and examples of seismic facies of the Melville Bay TMF using a 5-10 km grid of industry-quality 2D seismic data (TGS). The focus will primarily be on the inception and early stage of glacial fan development. Comparing the present-day topography with the regional geology shows that the paleo-icestreams exploited the Cenozoic infill of former rift basins that are more conducive to erosion than the adjoining ridges and structural highs. The TMF sequence is constructed by a series of progradational seismic units that represent successive steps in location of ice stream terminus and associated depocenters. The slope fronts of the prograding units show abundant signatures of sediment instability and mass-wasting but evidence of along-slope current-driven processes is also recognized presumably linked to interglacial sea level high-stands. The topset of each unit is characterized by planar erosion that merges landward into hummocky positive geometries with low internal reflectivity. These features are generally interpreted as subglacial landforms, e.g. terminal moraines and ice-contact deposits, associated with grounding zone wedges. Unlike the most recent TMF units deposited in front of the present trough, the oldest glacigenic units have built out from a Neogene sediment prism that forms the core of modern shallow-water banks. These topographic highs probably formed anchoring points facilitating the initial expansion of inland ice onto the shelf. The pre-glacial Neogene package displays typical contourite features concentrated along the mid-shelf region, while further basinward it is marked by intensive erosion and down-slope mass transport in the form of mega-slides. Our results suggests that shelf glaciation in these parts could have been facilitated by tectonic adjustments (e.g. relative fall in sea level) related to phases of tectonic uplift during latest Miocene and Pliocene/early Pleistocene. The present work contributes to a better understanding of the internal complexity of TMF systems as well as the underlying long-term mechanisms that evoked the Late Cenozoic development of the Greenland Ice Sheet.
Unzipping of the volcano arc, Japan
Stern, R.J.; Smoot, N.C.; Rubin, M.
1984-01-01
A working hypothesis for the recent evolution of the southern Volcano Arc, Japan, is presented which calls upon a northward-progressing sundering of the arc in response to a northward-propagating back-arc basin extensional regime. This model appears to explain several localized and recent changes in the tectonic and magrnatic evolution of the Volcano Arc. Most important among these changes is the unusual composition of Iwo Jima volcanic rocks. This contrasts with normal arc tholeiites typical of the rest of the Izu-Volcano-Mariana and other primitive arcs in having alkaline tendencies, high concentrations of light REE and other incompatible elements, and relatively high silica contents. In spite of such fractionated characteristics, these lavas appear to be very early manifestations of a new volcanic and tectonic cycle in the southern Volcano Arc. These alkaline characteristics and indications of strong regional uplift are consistent with the recent development of an early stage of inter-arc basin rifting in the southern Volcano Arc. New bathymetric data are presented in support of this model which indicate: 1. (1) structural elements of the Mariana Trough extend north to the southern Volcano Arc. 2. (2) both the Mariana Trough and frontal arc shoal rapidly northwards as the Volcano Arc is approached. 3. (3) rugged bathymetry associated with the rifted Mariana Trough is replaced just south of Iwo Jima by the development of a huge dome (50-75 km diameter) centered around Iwo Jima. Such uplifted domes are the immediate precursors of rifts in other environments, and it appears that a similar situation may now exist in the southern Volcano Arc. The present distribution of unrifted Volcano Arc to the north and rifted Mariana Arc to the south is interpreted not as a stable tectonic configuration but as representing a tectonic "snapshot" of an arc in the process of being rifted to form a back-arc basin. ?? 1984.
Sediment drifts and contourites on the continental margin off northwest Britain
NASA Astrophysics Data System (ADS)
Stoker, M. S.; Akhurst, M. C.; Howe, J. A.; Stow, D. A. V.
1998-01-01
Seismic reflection profiles and short cores from the continental margin off northwest Britain have revealed a variety of sediment-drift styles and contourite deposits preserved in the northeast Rockall Trough and Faeroe-Shetland Channel. The sediment drifts include: (1) distinctly mounded elongate drifts, both single- and multi-crested; (2) broad sheeted drift forms, varying from gently domed to flat-lying; and (3) isolated patch drifts, including moat-related drifts. Fields of sediment waves are locally developed in association with the elongate and gently domed, broad sheeted drifts. The contrasting styles of the sediment drifts most probably reflect the interaction between a variable bottom-current regime and the complex bathymetry of the continental margin. The bulk of the mounded/gently domed drifts occur in the northeast Rockall Trough, whereas the flat-lying, sheet-form deposits occur in the Faeroe-Shetland Channel, a much narrower basin which appears to have been an area more of sediment export than drift accumulation. Patch drifts are present in both basins. In the northeast Rockall Trough, the along-strike variation from single- to multi-crested elongate drifts may be a response to bottom-current changes influenced by developing drift topography. Muddy, silty muddy and sandy contourites have been recovered in sediment cores from the uppermost parts of the drift sequences. On the basis of their glaciomarine origin, these mid- to high-latitude contourites can be referred to, collectively, as glacigenic contourites. Both partial and complete contourite sequences are preserved; the former consist largely of sandy (mid-only) and top-only contourites. Sandy contourites, by their coarse-grained nature and their formation under strongest bottom-current flows, are the most likely to be preserved in the rock record. However, the very large scale of sediment drifts should be borne in mind with regard to the recognition of fossil contourites in ancient successions.
Multiple-dose pharmacokinetics of daptomycin during continuous venovenous haemodiafiltration.
Wenisch, Judith M; Meyer, Brigitte; Fuhrmann, Valentin; Saria, Katrin; Zuba, Clara; Dittrich, Peter; Thalhammer, Florian
2012-04-01
Daptomycin is bactericidal against Gram-positive bacteria, with peak-dependent effect but trough-dependent toxicity. This study was performed to develop dosing recommendations in continuous venovenous haemodiafiltration (CVVHDF). Nine critically ill patients in intensive care units of the Medical University Hospital of Vienna, requiring CVVHDF due to acute renal failure and antimicrobial treatment, were included. Blood and effluent samples were collected over 72 h to determine daptomycin concentrations by HPLC. Pharmacokinetic parameters were based on 10 sampling timepoints during the first 24 h, and peak and trough samples thereafter. An open two-compartment model was fitted to each subject's plasma concentration-time data. Simulations of serum concentration-time profiles after different doses and intervals were performed using ADAPT 5. Peak plasma concentrations with 6 mg/kg daptomycin were 62.2 ± 16.2, 66.1 ± 17.3 and 78.5 ± 22.1 mg/L on days 1, 2 and 3, respectively. The total clearance was 6.1 ± 4.9 mL/min, and the elimination half-life was 17.8 ± 9.7 h. Daptomycin was filtrated and could therefore be measured in the effluent. Protein binding was lower than that seen in healthy volunteers. The unbound fraction was 16 ± 4.5%. All subjects maintained trough serum concentrations above 4 mg/L, at which relevant pathogens are considered daptomycin-susceptible. Accumulation resulted when daptomycin was given every 24 h. Simulation of 8 mg/kg daptomycin given every 48 h resulted in adequate levels without accumulation. We recommend 8 mg/kg daptomycin every 48 h in patients on CVVHDF and therapeutic drug monitoring, if possible.
Cukor, Daniel; Ver Halen, Nisha; Pencille, Melissa; Tedla, Fasika; Salifu, Moro
2017-01-01
Nonadherence to immunosuppressant medication is a prevalent practice among kidney transplant recipients and has been associated with increased risk for graft failure and economic burden. The aim of this pilot study was to test whether a culturally sensitive cognitive-behavioral adherence promotion program could significantly improve medication adherence to tacrolimus prescription as measured by telephone pill counts among kidney transplant recipients. Thirty-three adult transplant recipients were less than 98% adherent to tacrolimus prescription based on 3 telephone pill counts and were randomized either to the 2-session cognitive-behavioral adherence promotion program or to standard care. The curriculum was developed from an iterative process with transplant recipients into a 2-session group program that provided psychoeducation, addressed barriers to adherence, fostered motivation to improve adherence behavior, and discussed cultural messages on adherence behavior. The intervention group displayed significantly higher levels of adherence when compared to the control group (t = 2.2, p = 0.04) and. similarly, when the amount of change was compared between the groups, the intervention group showed more change than the control condition (F (22,1) = 12.005, p = 0.003). Tacrolimus trough concentration levels were used as a secondary measure of adherence and, while there were no significant between-group differences for mean trough concentration levels, the variability in the trough levels did significantly decrease over time indicating more consistent pill-taking behavior in the intervention group. There is preliminary support for the pilot program as a successful intervention in helping patients with their immunosuppressant medication. © 2016 S. Karger AG, Basel.
Williet, Nicolas; Boschetti, Gilles; Fovet, Marion; Di Bernado, Thomas; Claudez, Pierre; Del Tedesco, Emilie; Jarlot, Camille; Rinaldi, Leslie; Berger, Anne; Phelip, Jean-Marc; Flourie, Bernard; Nancey, Stéphane; Paul, Stéphane; Roblin, Xavier
2017-11-01
We investigated whether serum trough levels of vedolizumab, a humanized monoclonal antibody against integrin α4β7, during the induction phase of treatment can determine whether patients will need additional doses (optimization of therapy) within the first 6 months. We conducted an observational study of 47 consecutive patients with Crohn's disease (CD; n = 31) or ulcerative colitis (UC; n = 16) who had not responded to 2 previous treatment regimens with antagonists of tumor necrosis factor and were starting therapy with vedolizumab at 2 hospitals in France, from June 2014 through April 2016. All patients were given a 300-mg infusion of vedolizumab at the start of the study, Week 2, Week 6, and then every 8 weeks; patients were also given corticosteroids during the first 4-6 weeks. Patients not in remission at Week 6 were given additional doses of vedolizumab at Week 10 and then every 4 weeks (extended therapy or optimization). Remission at Week 6 of treatment was defined as CD activity score below 150 points for patients with CD and a partial Mayo Clinic score of <3 points, without concomitant corticosteroids, for patients with UC. Blood samples were collected each week and serum levels of vedolizumab and antibodies against vedolizumab were measured using an enzyme-linked immunosorbent assay. Median trough levels of vedolizumab and interquartile ranges were compared using the nonparametric Mann-Whitney test. The primary objective was to determine whether trough levels of vedolizumab measured during the first 6 weeks of induction therapy associated with the need for extended treatment within the first 6 months. Based on response to therapy at Week 6, extended treatment was required for 30 of the 47 patients (23 patients with CD and 7 patients with UC). At Week 2, trough levels of vedolizumab for patients selected for extended treatment were 23.0 μg/mL (interquartile range, 14.0-37.0 μg/mL), compared with 42.5 μg/mL in patients who did not receive extended treatment (interquartile range, 33.5-50.7; P = .15). At Week 6, trough levels of vedolizumab <18.5 μg/mL were associated with need for extended therapy (100% positive predictive value, 46.2%; negative predictive value; area under the receiver operating characteristic curve, 0.72) within the first 6 months. Among patients who required extended treatment at Week 10, all of those with trough levels of vedolizumab <19.0 μg/mL at Week 6 had achieved clinical remission 4 weeks later (secondary responders). In a prospective study of patients with CD or UC receiving induction therapy with vedolizumab, low trough levels of vedolizumab at Week 6 (<19.0 μg/mL) are associated with need for additional doses (given at Week 10 and then every 4 weeks). All patients receiving these additional doses achieved a clinical response 4 weeks later. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.
The automated system for technological process of spacecraft's waveguide paths soldering
NASA Astrophysics Data System (ADS)
Tynchenko, V. S.; Murygin, A. V.; Emilova, O. A.; Bocharov, A. N.; Laptenok, V. D.
2016-11-01
The paper solves the problem of automated process control of space vehicles waveguide paths soldering by means of induction heating. The peculiarities of the induction soldering process are analyzed and necessity of information-control system automation is identified. The developed automated system makes the control of the product heating process, by varying the power supplied to the inductor, on the basis of information about the soldering zone temperature, and stabilizing the temperature in a narrow range above the melting point of the solder but below the melting point of the waveguide. This allows the soldering process automating to improve the quality of the waveguides and eliminate burn-troughs. The article shows a block diagram of a software system consisting of five modules, and describes the main algorithm of its work. Also there is a description of the waveguide paths automated soldering system operation, for explaining the basic functions and limitations of the system. The developed software allows setting of the measurement equipment, setting and changing parameters of the soldering process, as well as view graphs of temperatures recorded by the system. There is shown the results of experimental studies that prove high quality of soldering process control and the system applicability to the tasks of automation.
International Aviation (Selected Articles)
1991-09-11
THE ANAYLYSIS OF DYNAMIC FORCES IN AVIATION STRUCTURES Following along with the development of test manufacturing projects for many types of aircraft...type water troughs. All the main equipment embodies automated measurement controls. It is capable of obtaining test data and curves in a real time...results from thousands of calculations, and decisions were made to select the imaginary origin point to act as the turbulence flow origination point
FIB and CVD Fabrication of Carbon Nanostructures on Diamond and Quartz Substrates
2011-03-29
reveal non-linear conductivity, current injection trough insulating diamond, bistability of current flow, and coulomb blockade at room temperature...insulating diamond, bistability of current flow, and coulomb blockade at room temperature. Also we developed methods of fabrication of large uniform...T. Midletton, A. De Stefano, "Characterization of Pink Diamonds of Different Origin: Natural from Argyle, Irradiated, HPHT treated, Treated with
The spectrum of progressive derecho formation environments
NASA Astrophysics Data System (ADS)
Guastini, Corey T.
Progressive derechos are severe mesoscale convective systems that often form east of the Rocky Mountains during the warm season (May--August) and cause, by definition, straight-line wind damage along paths upwards of 400 km long. This study develops a subjective, seven-category classification scheme that spans the spectrum of progressive derecho formation environments from those dominated by robust upper-level ridges to those characterized by vigorous upper-level troughs. A climatology of 256 progressive derecho events is created for 1996--2013 and is categorized according to the developed classification scheme. Derecho initiation-relative composites are constructed for each of the seven groups using 0.5° Climate Forecast System Reanalysis data to document the environmental characteristics unique to each group as well as those shared among them. Finally, two in-depth case studies and five cursory case studies provide examples of the seven categories and reveal important nuances in mesoscale dynamic and thermodynamic structure inherent to all derecho cases. Results of the climatology show progressive derecho activity increases from 1 May through 1 July before decreasing again through the end of August and follows a northward trend in latitude from 1 May through 1 August before shifting slightly southward through the end of the warm season. Upslope flow in the vicinity of the Rocky Mountains initiates 28 percent of progressive derechos, upper-level troughs initiate 20 percent, 47 percent form in benign synoptic environments, and 5 percent are unclassifiable. Composite results show all progressive derecho initiation environments are marked by a long axis of instability caused by the overlap of high atmospheric moisture content and steep midlevel lapse rates, but the relative positions and strengths of upper-level troughs and ridges are crucial in determining how the instability axis develops and what its orientation in space will be. Case studies reveal instability axes forming in benign synoptic environments are generally zonally oriented and mainly the result of convergence of low-level moisture, whereas stronger synoptic-scale forcing forms meridionally oriented instability axes through the northward advection of Gulf moisture. The length and magnitude of these instability axes largely determines the duration and severity of a given progressive derecho.
Funken, K H; Sattler, C; Milow, B; De Oliveira, L; Blanco, J; Fernández, P; Malato, S; Brunott, M; Dischinge, N; Tratzky, S; Musci, M; de Oliveira, J C
2001-01-01
Solar photocatalytic detoxification of non-biodegradable chlorinated hydrocarbon solvents (NBCS) is carried out in different concentrating and non concentrating devices using TiO2 as a photocatalyst fixed on the inner surface of the reaction tubes or as a slurry catalyst which has to be removed from the treated water. The reaction is most effective using 200 mg/l of TiO2 as a slurry in a non concentrating CPC reactor. The concentrating parabolic trough reactor has a poor activity because of its minor irradiated reactor surface. Catalyst coated glass tubes are less efficient then the used slurry catalyst. Their advantage is that no catalyst has not to be removed from the treated water and there is no loss of activity during treatment. Yet their physical stability is not sufficient to be competitive to the slurry catalyst. Nevertheless the degradation results are very promising and will possibly lead to commercial applications of this technology.
Regional input to joint European space weather service
NASA Astrophysics Data System (ADS)
Stanislawska, I.; Belehaki, A.; Jansen, F.; Heynderickx, D.; Lilensten, J.; Candidi, M.
The basis for elaborating within COST 724 Action Developing the scientific basis for monitoring modeling and predicting Space Weather European space weather service is rich by many national and international activities which provide instruments and tools for global as well as regional monitoring and modeling COST 724 stimulates coordinates and supports Europe s goals of development and global cooperation by providing standards for timely and high quality information and knowledge in space weather Existing local capabilities are taken into account to develop synergies and avoid duplication The enhancement of environment monitoring networks and associated instruments technology yields mutual advantages for European service and regional services specialized for local users needs It structurally increases the integration of limited-area services generates a platform employing the same approach to each task differing mostly in input and output data In doing so it also provides complementary description of the environmental state within issued information A general scheme of regional services concept within COST 724 activity can be the processing chain from measurements trough algorithms to operational knowledge It provides the platform for interaction among the local end users who define what kind of information they need system providers who elaborate tools necessary to obtain required information and local service providers who do the actual processing of data and tailor it to specific user s needs Such initiative creates a unique possibility for small
Pushing concentration of stationary solar concentrators to the limit.
Winston, Roland; Zhang, Weiya
2010-04-26
We give the theoretical limit of concentration allowed by nonimaging optics for stationary solar concentrators after reviewing sun- earth geometry in direction cosine space. We then discuss the design principles that we follow to approach the maximum concentration along with examples including a hollow CPC trough, a dielectric CPC trough, and a 3D dielectric stationary solar concentrator which concentrates sun light four times (4x), eight hours per day year around.
Pushing concentration of stationary solar concentrators to the limit.
Winston, Roland; Zhang, Weiya
2010-04-26
We give the theoretical limit of concentration allowed by nonimaging optics for stationary solar concentrators after reviewing sun-earth geometry in direction cosine space. We then discuss the design principles that we follow to approach the maximum concentration along with examples including a hollow CPC trough, a dielectric CPC trough, and a 3D dielectric stationary solar concentrator which concentrates sun light four times (4x), eight hours per day year around.
Exact analytic flux distributions for two-dimensional solar concentrators.
Fraidenraich, Naum; Henrique de Oliveira Pedrosa Filho, Manoel; Vilela, Olga C; Gordon, Jeffrey M
2013-07-01
A new approach for representing and evaluating the flux density distribution on the absorbers of two-dimensional imaging solar concentrators is presented. The formalism accommodates any realistic solar radiance and concentrator optical error distribution. The solutions obviate the need for raytracing, and are physically transparent. Examples illustrating the method's versatility are presented for parabolic trough mirrors with both planar and tubular absorbers, Fresnel reflectors with tubular absorbers, and V-trough mirrors with planar absorbers.
Interseismic Coupling-Based Earthquake and Tsunami Scenarios for the Nankai Trough
NASA Astrophysics Data System (ADS)
Baranes, H.; Woodruff, J. D.; Loveless, J. P.; Hyodo, M.
2018-04-01
Theoretical modeling and investigations of recent subduction zone earthquakes show that geodetic estimates of interseismic coupling and the spatial distribution of coseismic rupture are correlated. However, the utility of contemporary coupling in guiding construction of rupture scenarios has not been evaluated on the world's most hazardous faults. Here we demonstrate methods for scaling coupling to slip to create rupture models for southwestern Japan's Nankai Trough. Results show that coupling-based models produce distributions of ground surface deformation and tsunami inundation that are similar to historical and geologic records of the largest known Nankai earthquake in CE 1707 and to an independent, quasi-dynamic rupture model. Notably, these models and records all support focused subsidence around western Shikoku that makes the region particularly vulnerable to flooding. Results imply that contemporary coupling mirrors the slip distribution of a full-margin, 1707-type rupture, and Global Positioning System measurements of surface motion are connected with the trough's physical characteristics.
Gas Forming a V-Shape Aluminum Sheet into a Trough of Saddle-Contour
NASA Astrophysics Data System (ADS)
Lee, Shyong; Lan, Hsien-Chin; Lee, Jye; Wang, Jian-Yih; Huang, J. C.; Chu, Chun Lin
2012-11-01
A sheet metal trough of aluminum alloys is manufactured by gas-forming process at 500 °C. The product with slope walls is of ~1.2 m long and ~260 mm opening width, comprising two conical sinks at two ends. The depth of one sink apex is ~350 mm, which results in the depth/width ratio reaching 1.4. To form such a complex shape with high aspect ratio, a pre-form of V-shape groove is prepared prior to the gas-forming work. When this double concave trough is turned upside down, the convex contour resembles the back of a twin hump camel. The formability of this configuration depends on the gas pressurization rate profile, the working temperature, material's micro-structure, as well as pre-form design. The latter point is demonstrated by comparing two aluminum alloys, AA5182 and SP5083, with nearly same compositions but very different grain sizes.
Dorsey, R.J.; Fluette, A.; McDougall, K.; Housen, B.A.; Janecke, S.U.; Axen, G.J.; Shirvell, C.R.
2007-01-01
Late Miocene to early Pliocene deposit at Split Mountain Gorge, California, preserve a record of basinal response to changes in regional tectonics, paleogeography, and evolution of the Colorado River. The base of the Elephant Trees Formation, magnetostratigraphically dated as 8.1 ?? 0.4 Ma, provides the earliest well-dated record of extension in the southwestern Salton Trough. The oldest marine sediments are ca. 6.3 Ma. The nearly synchronous timing of marine incursion in the Salton Trough and northern Gulf of California region supports a model for localization of Pacific-North America plate motion in the Gulf ca. 6 Ma. The first appearance of Colorado River sand at the Miocene-Pliocene boundary (5.33 Ma) suggests rapid propagation of the river to the Salton Trough, and supports a lake-spillover hypothesis for initiation of the lower Colorado River. ?? 2007 Geological Society of America.
The Valencia trough and the origin of the western Mediterranean basins
NASA Astrophysics Data System (ADS)
Vegas, R.
1992-03-01
Evolutionary models for the Valencia trough must be necessarily related to the Neogene-Present geodynamics of the western Mediterranean basins. All these basins occupy new space created in the wake of the westward translation of the Alboran block and the counter-clockwise rotation of the Corso-Sardinian block. This escape-tectonics, microplate dispersal, model can account for the co-existence and progressive migration of compressional and extensional strain fields within the Africa-Europe broad zone of convergence. In this escape-tectonics model, the Valencia trough has resulted in a complex evolution which includes: (1) latest Oligocene-Early Miocene rifting along the Catalan-Valencian margin due to the opening of the Gulf of Lions; (2) almost simultaneous, Early Miocene, transpressive thrusting in the Balearic margin related to the initiation of displacement of the Alboran block; and (3) Late Miocene generalized extension as a consequence of the opening of the South Balearic basin.
Slide Conveying of Granular Materials-Thinking Out of the Glovebox
NASA Technical Reports Server (NTRS)
Goddard, J. D.; Didwania, A. K.; Nott, P. R.
2000-01-01
The vibratory conveyor, routinely employed for normal-gravity transport of granular materials, usually consists of a continuous open trough vibrated sinusoidally to induce axial movement of a granular material. Motivated in part by a hypothetical application in zero gravity, we propose a novel modification of the vibratory conveyor based on a closed 2d trough operating in a "slide-conveying" mode, with the granular mass remaining permanently in contact with the trough walls. We present a detailed analysis of the mechanics of transport, based on a rigid-slab model for the granular mass with frictional (Coulomb) slip at the upper and lower walls. The form of the vibration cycle plays a crucial role, and the optimal conveying cycle is not the commonly assumed rectilinear sinusoidal motion. The conveying efficiency for the novel slide conveyor will be presented for several simple vibration cycles, including one believed to represent the theoretical optimum.
NASA Technical Reports Server (NTRS)
Adrian, M. L.; Gallagher, D. L.; Khazanov, G. V.; Chsang, S. W.; Liemohn, M. W.; Perez, J. D.; Green, J. L.; Sandel, B. R.; Mitchell, D. G.; Mende, S. B.;
2002-01-01
During a geomagnetic storm on 24 May 2000, the IMAGE Extreme Ultraviolet (EUV) camera observed a plasmaspheric density trough in the evening sector at L-values inside the plasmapause. Forward modeling of this feature has indicated that plasmaspheric densities beyond the outer wall of the trough are well below model expectations. This diminished plasma condition suggests the presence of an erosion process due to the interaction of the plasmasphere with ring current plasmas. We present an overview of EUV, energetic neutral atom (ENA), and Far Ultraviolet (FUV) camera observations associated with the plasmaspheric density trough of 24 May 2000, as well as forward modeling evidence of the lie existence of a plasmaspheric erosion process during this period. FUV proton aurora image analysis, convolution of ENA observations, and ring current modeling are then presented in an effort to associate the observed erosion with coupling between the plasmasphere and ring-current plasmas.
Coincident observations of ionospheric troughs and the equatorial plasmapause
NASA Technical Reports Server (NTRS)
Grebowsky, J. M.; Maynard, N. C.; Tulunay, Y. K.; Lanzerotti, L. J.
1976-01-01
Electron-density observations made in the topside ionosphere by the Ariel 4 and Isis 2 satellites are examined in conjunction with results obtained by Explorer 45 when it traversed the near-equatorial plasmapause with one hour (both UT and MLT) of the Ariel and Isis traversals of the same L coordinate. Both dusk and night observations are analyzed, and an attempt is made to show that depressions in ionospheric electron density occur in the vicinity of the plasmapause field line. It is concluded that the electron distributions observed in the electron-density troughs at 550 km near dusk by Ariel and at 1400 km near midnight by Isis do not always parallel variations in the light-ion distribution inferred from the Explorer plasmapause traversals and that there appears to be no specific feature of the main ionospheric trough which can be used to identify the plasmapause field line except in a statistical sense.
A new TRNSYS component for parabolic trough collector simulation
NASA Astrophysics Data System (ADS)
Drosou, Vassiliki; Valenzuela, Loreto; Dimoudi, Argiro
2018-03-01
This study describes and evaluates a new simulation component for parabolic trough collectors (PTCs). The new simulation component is implemented in the TRNSYS software environment by means of new Type that is suitable for integration into the calculation of a whole concentrating solar thermal plant, in order to evaluate the energy production of a PTC. The main advantage of the new Type is that is derived from experimental data available on efficiency Test Reports, according to the current European and International standards, rather than the theoretical approach considered in the existing parabolic trough component of TRNSYS library. The performance of the new Type has been validated with real experimental data obtained from the DISS solar test loop in Plataforma Solar de Almería, Spain. The paper describes the modelling approach, presents the comparison of simulation results with measurements taken at the DISS facility and evaluates the results.
Airborne Lidar measurements of the atmospheric pressure profile with tunable Alexandrite lasers
NASA Technical Reports Server (NTRS)
Korb, C. L.; Schwemmer, G. K.; Dombrowski, M.; Milrod, J.; Walden, H.
1986-01-01
The first remote measurements of the atmospheric pressure profile made from an airborne platform are described. The measurements utilize a differential absorption lidar and tunable solid state Alexandrite lasers. The pressure measurement technique uses a high resolution oxygen A band where the absorption is highly pressure sensitive due to collision broadening. Absorption troughs and regions of minimum absorption were used between pairs of stongly absorption lines for these measurements. The trough technique allows the measurement to be greatly desensitized to the effects of laser frequency instabilities. The lidar system was set up to measure pressure with the on-line laser tuned to the absorption trough at 13147.3/cm and with the reference laser tuned to a nonabsorbing frequency near 13170.0/cm. The lidar signal returns were sampled with a 200 range gate (30 vertical resoltion) and averaged over 100 shots.
NASA Astrophysics Data System (ADS)
Seton, M.; Williams, S.; Mortimer, N. N.; Meffre, S.; Moore, J.; Micklethwaite, S.; Zahirovic, S.
2013-12-01
The eastern Coral Sea region is an underexplored area at the northeastern corner of the Australian plate, where long-lived interaction between the Pacific and Australian plate boundaries has resulted in an intricate assemblage of deep oceanic basins and ridges, continental fragments and volcanic products. A paucity of marine geophysical and geological data from this complex region has resulted in the lack of a clear conceptual framework to describe its formation, ultimately affecting our understanding of the connection between the plate boundaries of the SW Pacific and SE Asia. In particular, the tectonic relationship between two back-arc basins, the Santa Cruz and d'Entrecasteaux Basins, and the South Rennell Trough, has yet to be resolved. In October-November, 2012, we collected 6,200 km of marine magnetic, 6,800 km of gravity and over 13,600 km2 of swath bathymetry data from the eastern Coral Sea onboard the RV Southern Surveyor. A complementary dredging program yielded useful samples from 14 seafloor sites. Our preliminary geochemical interpretation of the dredge samples obtained from the South Rennell Trough reveal volcanic rocks resembling MORB or BABB-type basalts, similar in composition to the recently re-analysed and dated ORSTOM dredges from the area that yielded ~28 Ma MORB-like basalts. Swath bathymetry profiles from the Santa Cruz Basin reveal that the South Rennell Trough extends into this basin, with seafloor spreading fabric being parallel to the trough. Preliminary analysis of the three full and four partial new magnetic anomaly profiles across the Santa Cruz Basin, coupled with limited existing profiles, reveals that the basin may have formed between Chrons 13-18 (~32-38 Ma), with an extinct spreading ridge along the inferred continuation of the South Rennell Trough, consistent with ORSTOM age dates. Our results suggest that the South Rennell Trough is an extinct southwestward propagating spreading ridge, which may have initiated along a pre-existing zone of weakness. A preliminary interpretation of the 4 magnetic profiles collected in the d'Entrecasteaux Basin and existing profiles of seafloor fabric shows that this basin does not share a common seafloor spreading history with the Santa Cruz Basin, as has been suggested previously. Our preliminary interpretation of the relationship between the Santa Cruz Basin, South Rennell Trough and d'Entrecasteaux Basin requires a re-interpretation of existing models of the SW Pacific to take into account a southwestward propagating spreading ridge between 38-32 Ma, contemporaneous with seafloor spreading further south in the North Loyalty Basin. Further work on age-dating and geochemical analysis of the newly collected dredge samples and an in-depth analysis of the magnetic anomalies in the d'Entrecasteaux Basin may further yield important information concerning the tectonic evolution of the area.
Enhanced TiO2 Photocatalytic Processing of Organic Wastes for Green Space Exploration
NASA Technical Reports Server (NTRS)
Udom, I.; Goswami, D. Y.; Ram, M. K.; Stefanakos, E. K.; Heep, A. F.; Kulis, M. J.; McNatt, J. S.; Jaworske, D. A.; Jones, C. A.
2013-01-01
The effect of transition metal co-catalysts on the photocatalytic properties of TiO2 was investigated. Ruthenium (Ru), palladium, platinum, copper, silver, and gold, were loaded onto TiO2 powders (anatase and mixed-phase P25) and screened for the decomposition of rhodamine B (RhB) under broad-band irradiation. The morphology and estimated chemical composition of photocatalysts were determined by scanning electron microscopy and energy dispersive spectroscopy, respectively. Brunhauer, Emmett and Teller (BET) analysis measured mass-specific surface area(s). X-ray diffraction analysis was performed to confirm the identity of titania phase(s) present. The BET surface area of anatase TiO2/Ru 1% (9.2 sq m/gm) was one of the highest measured of all photocatalysts prepared in our laboratory. Photolyses conducted under air-saturated and nitrogen-saturated conditions revealed photodegradation efficiencies of 85 and 2 percent, respectively, after 60 min compared to 58 percent with no catalyst. The cause of low photocatalytic activity under an inert atmosphere is discussed. TiO2/Ru 1% showed a superior photocatalytic activity relative to P25-TiO2 under broad-band irradiation. A potential deployment of photocatalytic technologies on a mission could be a reactor with modest enhancement in solar intensity brought about by a trough-style reactor, with reactants and catalyst flowing along the axis of the trough and therefore being illuminated for a controlled duration based on the flow rate.
Case study: A severe hailstorm and strong downbursts over northeastern Slovenia on June 16th 2009
NASA Astrophysics Data System (ADS)
Korosec, M.
2009-09-01
Introduction A strong isolated storm complex with bow echo feature crossed northeastern Slovenia in the late afternoon hours and caused extensive damage due to severe wind gusts near 30m/s, excessive rainfalls and large hail. Synoptic situation On June 16th 2009, an upper-level ridge persists over southern Europe while a positively tilted short-wave trough, connected to a complex deep trough over northern Europe, crosses central Europe. Accompanied by this trough, a cold front is extending southwestwards towards the Alps. A relatively strong jet steak wraps around the trough axis and creates strong shear environment which overlaps with a narrow band of unstable airmass present ahead of the coming frontal boundary. Behind this trough/front over central Europe, a high pressure area is developing with stable conditions. Over Slovenia, strong surface heating was on going through the day but lack of near-surface convergence zones, limited moisture and strong capping inversion surpressed any storm initiation in the afternoon. Presentation of research This case study will go through a research of damaging bow echo which caused extensive damage due to severe winds, excessive rainfalls and large hail over much of northeastern Slovenia. Numerous trees were down or uprooted and numerous roofs were blown off or were seriously damaged due to severe wind gusts near or exceeding 30m/s. At first stages, when an isolated severe storm entered Slovenia, it had classic high precipitation supercell features while it transformed into a powerful bow echo later on. Very large hail up to 6cm in diameter was first observed in southeast Austria and near the border with Slovenia, while later on the main threat was very strong wind gusts and intense rainfalls. This research paper will show a detailed analysis of the synoptic situation including analysis of satellite, radar and surface observations. Radar imagery clearly showed isolated storm trailing along the near-surface frontal boundary as a bow echo and also satellite imagery showed signs of extremely severe storm as overshooting tops, "cold ring" and "U-shape" features were observed. References - Skywarn Austria forum: (http://www.skywarn.at/forum/) - EARS radar and SFC observations archive (http://www.arso.gov.si) - EARS article: Porocilo o neurjih 16. junija 2009 - OSMER FVG (http://www.meteo.fvg.it) - ESSL/ESWD database (www.essl.org) - ESTOFEX convective maps (www.estofex.org) - EUMETSAT satellite imagery (www.eumetsat.int) - 24ur.com/RTVSLO web portal (www.24ur.com, www.rtvslo.si) - Sobota Info web portal (www.sobotainfo.com) - Pomurje web portal (www.pomurje.si) - Administration of the Republic of Slovenia for Civil Protection and Disaster Relief, www.sos112.si - Worldwide Skew-t diagrams (http://weather.uwyo.edu/upperair/europe.html)
Eustatic and tectonic controls on development and demise of Waulsortian carbonate buildups, Montana
DOE Office of Scientific and Technical Information (OSTI.GOV)
Precht, W.F.; Shepard, W.
1989-03-01
Deeper water Waulsortian carbonate buildups of Kinderhookian age are known from four localities in Montana. These buildups are situated within rhythmically bedded carbonate mudstones in the Paine Member of the Lodgepole formation. These buildups are mud-rich, byrozoan-crinoid mounds which contain abundant stromatactoid-like spar-filled cavities. The buildups are located along downdropped blocks on bounding faults of the Central Montana trough related to reactivation of a middle Proterozoic intracratonic rift margin (aulacogen). Sequence stratigraphic analyses of the Lodgepole throughout central Montana forms the basis for interpretation of buildup development and demise. Opening of the trough coupled with sea level rise formed threemore » distinct members of the Lodgepole, including (1) a transgressive surface marked by shallow-water deposits of the Cottonwood Canyon Member, (2) a transgressive systems tract of the Paine Member which can be separated into two distinct facies - a condensed section of deeper water carbonate mudstones to wackestones and the Waulsortian buildup facies which are encased within these rhythmically bedded deposits, and (3) a high-stand systems tract characterized by high-energy, cyclic, shoaling-upward crinoidal grainstones and oolites of the Woodhurst Member. Rapid eustatic rise and syntectonic subsidence during the transgressive systems tract outpassed buildup development and led to subsequent drowning. The lack of rapid reef building metazoans during the Mississippian is also suspect in explaining Waulsortian buildup demise.« less
Tectonic sequence stratigraphy, Early Permian Dry Mountain trough, east-central Nevada
DOE Office of Scientific and Technical Information (OSTI.GOV)
Snyder, W.S.; Gallegos, D.M.; Spinosa, C.
1991-06-01
The Early Permian Dry Mountain trough (DMT) of east-central Nevada is one of several tectonic basins and associated uplifts that developed along the continenetal margin during the latest Pennsylvanian-Early Permian Dry Mountain tectonic phase. The sequence stratigraphy reflects a combination of eustatic sea level changes and tectonic uplift or subsidence. Fewer than one to only a few million years separate the development of sequence boundaries within the DMT. At this scale, differences among published eustasy curves preclude their use as definitive tools to identify eustatically controlled sequence boundaries. Nevertheless, available data indicate several pulses of tectonism affected sedimentation within themore » DMT. The authors are attempting to develop criteria to distinguish tectonic from eustatic sequence boundaries. Detailed biostratigraphic data are required to provide an independent check on the correlation of sequence boundaries between measured sections. For example, the same age boundary may reflect tectonic uplift in one part of the basin and subsidence in another. The uplift may or may not result in subaerial exposure and erosion. For those boundaries that do not result from subaerial exposure, lithofacies and biofacies analyses are required to infer relative uplift (water depth decrease) or subsidence (water depth increase). There are inherent resolution limitations in both the paleontologic and sedimentologic methodologies. These limitations, combined with those of eustasy curves, dictate the preliminary nature of their results.« less
Discontinuity minimization for omnidirectional video projections
NASA Astrophysics Data System (ADS)
Alshina, Elena; Zakharchenko, Vladyslav
2017-09-01
Advances in display technologies both for head mounted devices and television panels demand resolution increase beyond 4K for source signal in virtual reality video streaming applications. This poses a problem of content delivery trough a bandwidth limited distribution networks. Considering a fact that source signal covers entire surrounding space investigation reviled that compression efficiency may fluctuate 40% in average depending on origin selection at the conversion stage from 3D space to 2D projection. Based on these knowledge the origin selection algorithm for video compression applications has been proposed. Using discontinuity entropy minimization function projection origin rotation may be defined to provide optimal compression results. Outcome of this research may be applied across various video compression solutions for omnidirectional content.
Integrated solar energy system optimization
NASA Astrophysics Data System (ADS)
Young, S. K.
1982-11-01
The computer program SYSOPT, intended as a tool for optimizing the subsystem sizing, performance, and economics of integrated wind and solar energy systems, is presented. The modular structure of the methodology additionally allows simulations when the solar subsystems are combined with conventional technologies, e.g., a utility grid. Hourly energy/mass flow balances are computed for interconnection points, yielding optimized sizing and time-dependent operation of various subsystems. The program requires meteorological data, such as insolation, diurnal and seasonal variations, and wind speed at the hub height of a wind turbine, all of which can be taken from simulations like the TRNSYS program. Examples are provided for optimization of a solar-powered (wind turbine and parabolic trough-Rankine generator) desalinization plant, and a design analysis for a solar powered greenhouse.
Deep drivers of mesoscale circulation in the central Rockall Trough
NASA Astrophysics Data System (ADS)
Sherwin, T. J.; Alyenik, D.; Dumont, E.; Inall, M.
2014-11-01
Mesoscale variability in the central Rockall Trough between about 56 and 58° N has been investigated using a combination of ship-borne, underwater glider and gridded satellite altimeter measurements. Altimeter observations show that mesoscale features such as eddies and large scale circulation cells are ubiquitous phenomena. They have horizontal length scales of order 100 km with vertical scales of over 1000 m and are associated with mean current speeds (over the upper 1000 m) of 15 ± 7 cm s-1. Monthly area averaged surface Eddy Kinetic Energy (EKE) has substantial inter-annual variability, which at times can dominate a mean seasonal signal that varies from a maximum in May (74 cm2 s-2) to a minimum in October (52 cm2 s-2) and has increased gradually since 1992 at about 1.1 cm2 s-2 per year. A five month glider mission in the Trough showed that much of this energy comes from features that are located over 1000 m below the surface in the deep cold waters of the Trough (possibly from eddies associated the North Atlantic Current). The surface currents from altimeters had similar magnitude to the drift currents averaged over 1000 m from the glider in the stratified autumn, but were half the deep water speed during late winter. Although the mesoscale features move in an apparent random manner they may also be quasi-trapped by submarine topography such as seamounts. Occasionally anti-cyclonic and cyclonic cells combine to cause a coherent westward deflection of the European slope current that warms the Rockall side of the Trough. Such deflections contribute to the inter-annual variability in the observed temperature and salinity that are monitored in the upper 800 m of the Trough. By combining glider and altimeter measurements it is shown that altimeter measurements fail to observe a 15 cm s-1 northward flowing slope current on the eastern side and a small persistent southward current on the western side. There is much to be gained from the synergy between satellite altimetry and in situ glider observations both in the interpretation of their separate data sets and in aiding glider pilots to steer their vehicles through EKE active regions such as the north-east Atlantic.
The role of water in the petrogenesis of Marina trough magmas
NASA Astrophysics Data System (ADS)
Stolper, Edward; Newman, Sally
1994-02-01
Most variations in composition among primitive basalts from the Mariana back-arc trough can be explained by melting mixtures of an N-type mid-ocean ridge basalt (NMORB) mantle source and an H2O rich component, provided the degree of melting is positively and approximately linearly correlated with the proportion of the H2O-rich component in the mixture. We conclude that the degrees of melting by which Mariana trough magmas are generated increase from magmas similar to NMORB, through more H2O-enriched basalts, to 'arc-like' basalts, and that this increase is due to the lowering of the solidus of mantle peridotite that accompanies addition of the H2O-rich component. The H2O-rich component is likely to be ultimately derived from fluid from a subducting slab, but we propose that by the time fluids reach the source regions of Mariana trough basalts, they have interacted with sufficient mantle material that for all but the most incompatible of elements (with respect to fluid-mantle interaction), they are in equilibrium with the mantle. In contrast, fluids added to the source regions of Mariana island-arc magmas have typically interacted with less mantle and thus retain the signature of slab-derived fluids to varying degrees for all but the most compatible elements. Primitive Mariana arc basalts can be generated by melting mixtures of such incompletely exchanged slab-derived fluids and sources similar to NMORB-type mantle sources, but the degrees of melting are typically higher than those of Mariana trough NMORB and the sources have been variably depleted relative to the back-arc sources by previous melt extraction. This depletion may be related to earlier extraction of back-arc basin magmas or may evolve by repeated fluxing of the sources as fluid is continually added to them in the regions of arc magma generation. If fluid with partitioning behavior relative to the solid mantle similar to that deduced for the H2O-rich component involved in the generation of Mariana trough basalts were extracted from primitive mantle, the residual mantle would have many of the minor and trace element characteristics of typical oceanic upper mantle; primitive mantle enriched in such fluid would be a satisfactory source for the continental crust in terms of its trace and minor element chemical composition.
NASA Astrophysics Data System (ADS)
Bentley, S. J.; Muhammad, Z.; Dickens, J.; Droxler, A.; Peterson, L.; Opdyke, B.
2004-12-01
Multicores and jumbo piston cores were collected from the Moresby Trough from the R/V Melville in March-April 204 to study patterns of off-shelf sediment flux from the Gulf of Papua to the deep sea over Pleistocene-Holocene timescales. The Moresby Trough represents the primary deep-sea sediment conduit linking the Source to Sink Gulf of Papua study area to the north with the Coral Sea Basin to the south. Core locations were navigated from the surface using dynamic positioning and multibeam bathymetric mosaics collected during the cruise. Selected cores have been analyzed using a multi-sensor core logger, X-radiography, granulometry, and Pb-210 geochronology. Most piston cores collected from the Moresby Trough contain abundant mafic sandy turbidites overlain by fine-grained hemipelagic deposits 1-2 m thick. X-radiographs of multicores reveal mostly bioturbated hemipelagics. However, one core, MV25-0403-24MC, was collected from the axis of a primary channel, and contains at least two fine-grained turbidites within the upper 0.5 m of sediment. The uppermost turbidite contains low but uniform activities of excess Pb-210, and may have been 15-20 cm thick at the time of deposition (i.e., before subsequent disruption by bioturbation), based on fabric and radiochemical evidence. Application of a simple box-model for physical mixing (i.e., during the flow) and subsequent decay suggests that the uppermost turbidite was deposited 70-120 years before present. Bioturbation has since reworked about 60% of the bed, suggesting that such beds will only escape destruction by bioturbation if they are > 10 cm thick, and are deposited more frequently than once per century. Based on these observations, we suggest that gravity flows are presently active in the Moresby trough, and may account for a significant fraction of the hemipelagic drape present in channel systems. However, fabric evidence for these thin, fine-grained beds may be obscured by subsequent bioturbation. Also, at some point in the past, possibly at the onset of the Holocene Transgression, the character of sediment flux to the Moresby Trough shifted from sandy mafic-rich sandy turbidity currents to much finer sediments, delivered downslope by both benthic flows and vertical flux through the water column.
Kuniansky, Eve L.; Bellino, Jason C.; Dixon, Joann F.
2012-01-01
The Floridan aquifer system (FAS) covers an area of approximately 100,000 square miles in Florida and parts of Georgia, South Carolina, Alabama, and Mississippi. Groundwater wells for water supply were first drilled in the late 1800s and by the year 2000, the FAS was the primary source of drinking water for about 10 million people. One of the methods for assessing groundwater availability is the development of regional or subregional groundwater flow models of the aquifer system that can be used to develop water budgets spatially and temporally, as well as evaluate the groundwater resource change over time. Understanding the distribution of transmissivity within the FAS is critical to the development of groundwater flow models. The map presented herein differs from previously published maps of the FAS in that it is based on interpolation of 1,487 values of transmissivity. The transmissivity values in the dataset range from 8 to 9,000,000 feet squared per day (ft2/d) with the majority of the values ranging from 10,000 to 100,000 ft2/d. The wide range in transmissivity (6 orders of magnitude) is typical of carbonate rock aquifers, which are characterized by a wide range in karstification. Commonly, the range in transmissivity is greatest in areas where groundwater flow creates conduits in facies that dissolve more readily or areas of high porosity units that have interconnected vugs, with diameters greater than 0.1 foot. These are also areas where transmissivity is largest. Additionally, first magnitude springsheds and springs are shown because in these springshed areas, the estimates of transmissivity from interpolation may underestimate the actual range in transmissivity. Also shown is an area within the Gulf Trough in Georgia where high yielding wells are unlikely to be developed in the Upper Floridan aquifer. The interpolated transmissivity ranges shown on this map reflect the geologic structure and karstified areas. Transmissivity is large in the areas where the system is unconfined, such as west-central Florida and southwest Georgia just northwest of the Gulf Trough. Transmissivity is small along the Gulf Trough and Southwest Georgia Embayment (referred to as Apalachicola Embayment in some reports). Transmissivity is also small in the thin, updip part of the system near its northern boundary. Another area of large transmissivity coincides with the Southeast Georgia Embayment.
Shielded serpentine traveling wave tube deflection structure
Hudson, C.L.; Spector, J.
1994-12-27
A shielded serpentine slow wave deflection structure is disclosed having a serpentine signal conductor within a channel groove. The channel groove is formed by a serpentine channel in a trough plate and a ground plane. The serpentine signal conductor is supported at its ends by coaxial feed through connectors. A beam interaction trough intersects the channel groove to form a plurality of beam interaction regions wherein an electron beam may be deflected relative to the serpentine signal conductor. 4 figures.
DETAIL VIEW OF CLASSIFIER, TAILINGS LAUNDER TROUGH, LINE SHAFTS, AND ...
DETAIL VIEW OF CLASSIFIER, TAILINGS LAUNDER TROUGH, LINE SHAFTS, AND CONCENTRATION TABLES, LOOKING SOUTHWEST. SLURRY EXITING THE BALL MILL WAS COLLECTED IN AN AMALGAMATION BOX (MISSING) FROM THE END OF THE MILL, AND INTRODUCED INTO THE CLASSIFIER. THE TAILINGS LAUDER IS ON THE GROUND AT LOWER RIGHT. THE LINE SHAFTING ABOVE PROVIDED POWER TO THE CONCENTRATION TABLES BELOW AT CENTER RIGHT. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA
Fate and Transport of Tungsten at Camp Edwards Small Arms Ranges
2007-08-01
area into the lower berm and/or trough. A similar approach was used in the lower berm area with samples collected from soil sloughing from the...bucket au- ger to collect samples beneath the bullet pockets and the trough. A multi - increment, subsurface soil sample was made by combining the...range. From these soil profiles, a total of 72 multi -increment subsurface soil sam- ples was collected (Table 2). The auger was cleaned between holes
DETAIL VIEW OF BALL MILL FEED SYSTEM, MOUTH OF CLASSIFIER, ...
DETAIL VIEW OF BALL MILL FEED SYSTEM, MOUTH OF CLASSIFIER, AND ORE BIN CHUTE, LOOKING EAST NORTHEAST. CRUSHED ORE FROM THE SECONDARY ORE BIN WAS INTRODUCED INTO THE FEED TROUGH VIA A CHUTE. AS THE BALL MILL TURNED, THE ROUND SCOOP ALSO TURNED IN THE TROUGH TO CHANNEL ORE INTO THE BALL MILL. SEE CA-292-14 FOR IDENTICAL B&W NEGATIVE. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA
DETAIL VIEW OF BALL MILL FEED SYSTEM, MOUTH OF CLASSIFIER, ...
DETAIL VIEW OF BALL MILL FEED SYSTEM, MOUTH OF CLASSIFIER, AND ORE BIN CHUTE, LOOKING EAST NORTHEAST. CRUSHED ORE FROM THE SECONDARY ORE BIN WAS INTRODUCED INTO THE FEED TROUGH VIA A CHUTE. AS THE BALL MILL TURNED, THE ROUND SCOOP ALSO TURNED IN THE TROUGH TO CHANNEL ORE INTO THE BALL MILL. SEE CA-292-20 (CT) FOR IDENTICAL COLOR TRANSPARENCY. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA
Bottom-water observations in the Vema fracture zone
NASA Astrophysics Data System (ADS)
Eittreim, Stephen L.; Biscaye, Pierre E.; Jacobs, Stanley S.
1983-03-01
The Vema fracture zone trough, at 11°N between 41° and 45°E, is open to the west at the 5000-m level but is silled at the 4650-m level on the east where it intersects the axis of the Mid-Atlantic Ridge. The trough is filled with Antarctic Bottom Water (AABW) with a potential temperature of 1.32°C and salinity of 34.82 ppt. The bottom water is thermally well mixed in a nearly homogeneous layer about 700 m thick. The great thickness of this bottom layer, as compared with the bottom-water structure of the western Atlantic basin, may result from enhanced mixing induced by topographic constriction at the west end of the fracture zone trough. A benthic thermocline, with potential temperature gradients of about 1.2 mdeg m-1, is associated with an abrupt increase in turbidity with depth at about 1200 m above bottom. A transitional layer of more moderate temperature gradients, about 0.4 mdeg m-1, lies between the benthic thermocline above and the AABW below. The AABW layer whose depth-averaged suspended paniculate concentrations range from 8 to 19 μg L-1, is consistently higher in turbidity than the overlying waters. At the eastern end of the trough, 140 m below sill depth, very low northeastward current velocities, with maximums of 3 cm s-1, were recorded for an 11-day period.
NASA Astrophysics Data System (ADS)
Kalén, Ola; Assmann, Karen M.; Wåhlin, Anna K.; Ha, Ho Kyung; Kim, Tae Wan; Lee, Sang Hoon
2016-01-01
The glaciers that drain the West Antarctic Ice Sheet into the Amundsen Sea are accelerating and experiencing increased basal melt of the floating ice shelves. Warm and salty deep water has been observed to flow southward in deep troughs leading from the shelf break to the inner shelf area where the glaciers terminate. It has been suggested that the melting induced by this warm water is responsible for the acceleration of the glaciers. Here we investigate the structure of the currents and the associated heat flow on the shelf using in-situ observations from 2008 to 2014 in Dotson Trough, the main channel in the western part of the Amundsen Sea shelf, together with output from a numerical model. The model is generally able to reproduce the observed velocities and temperatures in the trough, albeit with a thicker warm bottom layer. In the absence of measurements of sea surface height we define the barotropic component of the flow as the vertical average of the velocity. It is shown that the flow is dominated by warm barotropic inflows on the eastern side and colder and fresher barotropic outflows on the western side. The transport of heat appears to be primarily induced by this clockwise barotropic circulation in the trough, contrary to earlier studies emphasizing a bottom-intensified baroclinic inflow as the main contributor.
NASA Astrophysics Data System (ADS)
Hakkarainen, Elina; Tähtinen, Matti
2016-05-01
Demonstrations of direct steam generation (DSG) in linear Fresnel collectors (LFC) have given promising results related to higher steam parameters compared to the current state-of-the-art parabolic trough collector (PTC) technology using oil as heat transfer fluid (HTF). However, DSG technology lacks feasible solution for long-term thermal energy storage (TES) system. This option is important for CSP technology in order to offer dispatchable power. Recently, molten salts have been proposed to be used as HTF and directly as storage medium in both line-focusing solar fields, offering storage capacity of several hours. This direct molten salt (DMS) storage concept has already gained operational experience in solar tower power plant, and it is under demonstration phase both in the case of LFC and PTC systems. Dynamic simulation programs offer a valuable effort for design and optimization of solar power plants. In this work, APROS dynamic simulation program is used to model a DMS linear Fresnel solar field with two-tank TES system, and example simulation results are presented in order to verify the functionality of the model and capability of APROS for CSP modelling and simulation.
High-temperature solar receiver integrated with a short-term storage system
NASA Astrophysics Data System (ADS)
Giovannelli, Ambra; Bashir, Muhammad Anser; Archilei, Erika Maria
2017-06-01
Small-Scale Concentrated Solar Power Plants could have a potential market for off-grid applications in rural contexts with limited access to the electrical grid and favorable environmental characteristics. Some Small-Scale plants have already been developed, like the 25-30 kWe Dish-Stirling engine. Other ones are under development as, for example, plants based on Parabolic Trough Collectors coupled with Organic Rankine Cycles. Furthermore, the technological progress achieved in the development of new small high-temperature solar receiver, makes possible the development of interesting systems based on Micro Gas Turbines coupled with Dish collectors. Such systems could have several advantages in terms of costs, reliability and availability if compared with Dish-Stirling plants. In addition, Dish-Micro Gas Turbine systems are expected to have higher performance than Solar Organic Rankine Cycle plants. The present work focuses the attention on some challenging aspects related to the design of small high-temperature solar receivers for Dish-Micro Gas Turbine systems. Natural fluctuations in the solar radiation can reduce system performance and damage seriously the Micro Gas Turbine. To stabilize the system operation, the solar receiver has to assure a proper thermal inertia. Therefore, a solar receiver integrated with a short-term storage system based on high-temperature phase-change materials is proposed in this paper. Steady-state and transient analyses (for thermal storage charge and discharge phases) have been carried out using the commercial CFD code Ansys-Fluent. Results are presented and discussed.
Alternative Energy Sources for United States Air Force Installations
1975-08-01
easy to maintain, and have a relatively long life expectancy. b. Linear Focus Parabolic trough collectors have been fabricated by two primary methods...engineered and economically manufactured and dis- tributed solar collectors . Development, optimization, production design, and manufacture of these units is...193 and domestic hnt water heating. These systems function by converting the solar energy incident on a collector surface to thermal energy in a working
Turbulent Structure Under Short Fetch Wind Waves
2015-12-01
1970) developed the LFT utilizing the concurrent measurement of sea surface elevation (η) and the near surface velocities to isolate the wave...Layers and Air-Sea Transfer program by making very high spatial resolution profile measurements of the 3-D velocity field into the crest-trough...distribution is unlimited TURBULENT STRUCTURE UNDER SHORT FETCH WIND WAVES Michael J. Papa Lieutenant Commander, United States Navy B.S., United States Naval
NASA Astrophysics Data System (ADS)
Becerra Lopez, Humberto Ruben
2007-12-01
High expansion of power demand is expected in the Upper Rio Grande region (El Paso, Hudspeth, Culberson, Jeff Davis, Presidio and Brewster counties) as a result of both electrical demand growth and decommissioning of installed capacity. On the supply side a notable deployment of renewable power technologies can be projected owing to the recent introduction of a new energy policy in Texas, which attempts to reach 10,000 installed-MWe of renewable capacity for 2025. Power generation fueled by natural-gas might consistently expand due to the encouraged use of this fuel. In this context the array of participating technologies can be optimized, which, within a sustainability framework, translates into a multidimensional problem. The solution to the problem is presented through this dissertation in two main parts. The first part solves the thermodynamic-environmental problem through developing a dynamic model to project maximum allowable expansion of technologies. Predetermined alternatives include diverse renewable energy technologies (wind turbine, photovoltaic conversion, hybrid solar thermal parabolic trough, and solid oxide fuel cells), a conventional fossil-fuel technology (natural gas combined-cycle), and a breakthrough fossil-fuel technology (solid oxide fuel cells). The analysis is based on the concept of cumulative exergy consumption, expanded to include abatement of emissions. A Gompertz sigmoid growth is assumed and constrained by both exergetic self-sustenance and regional energy resource availability. This part of the analysis assumes that power demand expansion is met by full deployment of alternative technologies backed up by conventional technology. Results show that through a proper allowance for exergy reinvestment the power demand expansion may be met largely by alternative technologies minimizing the primary resource depletion. The second part of the study makes use of the dynamic model to support a multi-objective optimization routine, where the exergetic and economic costs are established as primary competing factors. An optimization algorithm is implemented using the constraint method. The solution is given as Pareto optimality with arrays for minimum cost and possible arrays for the tradeoff front. These arrays are further analyzed in terms of sustainability, cumulative exergy loss (i.e. irreversibilities and waste exergy) and incremental economic cost, and the results are compared with the goals of current legislated energy policy.
NASA Astrophysics Data System (ADS)
Hole, J. A.; Stock, J. M.; Fuis, G. S.; Rymer, M. J.; Murphy, J. M.; Sickler, R. R.; Criley, C. J.; Goldman, M.; Catchings, R. D.; Ricketts, J. W.; Gonzalez-Fernandez, A.; Driscoll, N.; Kent, G.; Harding, A. J.; Klemperer, S. L.
2009-12-01
The Salton Seismic Imaging Project (SSIP) and coordinated projects will acquire seismic data in and across the Salton Trough in southern California and northern Mexico, including the Coachella, Imperial, and Mexicali Valleys. These projects address both rifting processes at the northern end of the Gulf of California extensional province and earthquake hazards at the southern end of the San Andreas Fault system. In the central Salton Trough, North American lithosphere appears to have been rifted completely apart. Based primarily on a 1979 seismic refraction project, the 20-22 km thick crust is apparently composed entirely of new crust added by magmatism from below and sedimentation from above. The new data will constrain the style of continental breakup, the role and mode of magmatism, the effects of rapid Colorado River sedimentation upon extension and magmatism, and the partitioning of oblique extension. The southernmost San Andreas Fault is considered at high risk of producing a large damaging earthquake, yet structures of the fault and adjacent basins are poorly constrained. To improve hazard models, SSIP will image the geometry of the San Andreas and Imperial Faults, structure of sedimentary basins in the Salton Trough, and three-dimensional seismic velocity of the crust and uppermost mantle. SSIP and collaborating projects have been funded by several different programs at NSF and the USGS. These projects include seven lines of land refraction and low-fold reflection data, airguns and OBS data in the Salton Sea, coordinated fieldwork for onshore-offshore and 3-D data, and a densely sampled line of broadband stations across the trough. Fieldwork is tentatively scheduled for 2010. Preliminary work in 2009 included calibration shots in the Imperial Valley that quantified strong ground motion and proved lack of harm to agricultural irrigation tile drains from explosive shots. Piggyback and complementary studies are encouraged.
Analysis of Earthquake Source Spectra in Salton Trough
NASA Astrophysics Data System (ADS)
Chen, X.; Shearer, P. M.
2009-12-01
Previous studies of the source spectra of small earthquakes in southern California show that average Brune-type stress drops vary among different regions, with particularly low stress drops observed in the Salton Trough (Shearer et al., 2006). The Salton Trough marks the southern end of the San Andreas Fault and is prone to earthquake swarms, some of which are driven by aseismic creep events (Lohman and McGuire, 2007). In order to learn the stress state and understand the physical mechanisms of swarms and slow slip events, we analyze the source spectra of earthquakes in this region. We obtain Southern California Seismic Network (SCSN) waveforms for earthquakes from 1977 to 2009 archived at the Southern California Earthquake Center (SCEC) data center, which includes over 17,000 events. After resampling the data to a uniform 100 Hz sample rate, we compute spectra for both signal and noise windows for each seismogram, and select traces with a P-wave signal-to-noise ratio greater than 5 between 5 Hz and 15 Hz. Using selected displacement spectra, we isolate the source spectra from station terms and path effects using an empirical Green’s function approach. From the corrected source spectra, we compute corner frequencies and estimate moments and stress drops. Finally we analyze spatial and temporal variations in stress drop in the Salton Trough and compare them with studies of swarms and creep events to assess the evolution of faulting and stress in the region. References: Lohman, R. B., and J. J. McGuire (2007), Earthquake swarms driven by aseismic creep in the Salton Trough, California, J. Geophys. Res., 112, B04405, doi:10.1029/2006JB004596 Shearer, P. M., G. A. Prieto, and E. Hauksson (2006), Comprehensive analysis of earthquake source spectra in southern California, J. Geophys. Res., 111, B06303, doi:10.1029/2005JB003979.
Vertical Displacement of the Surface Area over the Leakage to the Transverse salt Mine in 1992-2012
NASA Astrophysics Data System (ADS)
Lipecki, Tomasz
2018-03-01
The leakage of water in the salt mine caused considerable deformation of the surface. This article shows the vertical displacement in the area of leakage to the mine excavation, measured by precision leveling, carried out from the first days of leakage in 1992 until 2012. The geological and hydrogeological conditions of the mine, as well as the associated water hazards were described, which in conjunction with the inconvenient location of the excavation site in the northern frontage of the Carpathians and also inadequately conducted mining operations, contributed to the risk of flooding mine. The analysis of the vertical movements of the surface - subsidence and uplift - were present as well as the process of formation of the depression trough in the form of maps and graphs. The analyzes were based on 49 measurement series, starting from the first days of the disaster within the next 20 years. The course of development of the depression trough and the condition of the surface after stopping the water from the rock mass has been shown, which caused the surface to uplift.
Summary of engineering-scale experiments for the Solar Detoxification of Water project
NASA Astrophysics Data System (ADS)
Pacheco, J. E.; Yellowhorse, L.
1992-03-01
This report contains a summary of large-scale experiments conducted at Sandia National Laboratories under the Solar Detoxification of Water project. The objectives of the work performed were to determine the potential of using solar radiation to destroy organic contaminants in water by photocatalysis and to develop the process and improve its performance. For these experiments, we used parabolic troughs to focus sunlight onto glass pipes mounted at the trough's focus. Water spiked with a contaminant and containing suspended titanium dioxide catalyst was pumped through the illuminated glass pipe, activating the catalyst with the ultraviolet portion of the solar spectrum. The activated catalyst creates oxidizers that attack and destroy the organics. Included in this report are a summary and discussion of the implications of experiments conducted to determine: the effect of process kinetics on the destruction of chlorinated solvents (such as trichloroethylene, perchloroethylene, trichloroethane, methylene chloride, chloroform and carbon tetrachloride), the enhancement due to added hydrogen peroxide, the optimal catalyst loading, the effect of light intensity, the inhibition due to bicarbonates, and catalyst issues.
Bedload-surrogate monitoring technologies
Gray, John R.; Laronne, Jonathan B.; Marr, Jeffrey D.G.
2010-01-01
Advances in technologies for quantifying bedload fluxes and in some cases bedload size distributions in rivers show promise toward supplanting traditional physical samplers and sampling methods predicated on the collection and analysis of physical bedload samples. Four workshops held from 2002 to 2007 directly or peripherally addressed bedload-surrogate technologies, and results from these workshops have been compiled to evaluate the state-of-the-art in bedload monitoring. Papers from the 2007 workshop are published for the first time with this report. Selected research and publications since the 2007 workshop also are presented. Traditional samplers used for some or all of the last eight decades include box or basket samplers, pan or tray samplers, pressure-difference samplers, and trough or pit samplers. Although still useful, the future niche of these devices may be as a means for calibrating bedload-surrogate technologies operating with active- and passive-type sensors, in many cases continuously and automatically at a river site. Active sensors include acoustic Doppler current profilers (ADCPs), sonar, radar, and smart sensors. Passive sensors include geophones (pipes or plates) in direct contact with the streambed, hydrophones deployed in the water column, impact columns, and magnetic detection. The ADCP for sand and geophones for gravel are currently the most developed techniques, several of which have been calibrated under both laboratory and field conditions. Although none of the bedload-surrogate technologies described herein are broadly accepted for use in large-scale monitoring programs, several are under evaluation. The benefits of verifying and operationally deploying selected bedload-surrogate monitoring technologies could be considerable, providing for more frequent and consistent, less expensive, and arguably more accurate bedload data obtained with reduced personal risk for use in managing the world's sedimentary resources. Twenty-six papers are published for the first time as part of the 2007 International Bedload-Surrogate Monitoring Workshop (listed in table 2 in alphabetical order by name of first author). Sequential page numbering of the papers begins on page 38, after the last page of the report. The report plus the 26 papers comprise 430 pages.
NASA Astrophysics Data System (ADS)
Kari, Leif
2017-09-01
The dynamic stiffness of a chemically and physically ageing rubber vibration isolator in the audible frequency range is modelled as a function of ageing temperature, ageing time, actual temperature, time, frequency and isolator dimension. In particular, the dynamic stiffness for an axially symmetric, homogeneously aged rubber vibration isolator is derived by waveguides where the eigenmodes given by the dispersion relation for an infinite cylinder satisfying traction free radial surface boundary condition are matched to satisfy the displacement boundary conditions at the lateral surface ends of the finite rubber cylinder. The constitutive equations are derived in a companion paper (Part 1). The dynamic stiffness is calculated over the whole audible frequency range 20-20,000 Hz at several physical ageing times for a temperature history starting at thermodynamic equilibrium at +25°C and exposed by a sudden temperature step down to -60°C and at several chemical ageing times at temperature +25°C with simultaneous molecular network scission and reformation. The dynamic stiffness results are displaying a strong frequency dependence at a short physical ageing time, showing stiffness magnitude peaks and troughs, and a strong physical ageing time dependence, showing a large stiffness magnitude increase with the increased physical ageing time, while the peaks and troughs are smoothed out. Likewise, stiffness magnitude peaks and troughs are frequency-shifted with increased chemical ageing time. The developed model is possible to apply for dynamic stiffness prediction of rubber vibration isolator over a broad audible frequency range under realistic environmental condition of chemical ageing, mainly attributed to oxygen exposure from outside and of physical ageing, primarily perceived at low-temperature steps.
NASA Astrophysics Data System (ADS)
Yu, Mo; Evans, Neal J., II; Dodson-Robinson, Sarah E.; Willacy, Karen; Turner, Neal J.
2017-12-01
Turbulence is the leading candidate for angular momentum transport in protoplanetary disks and therefore influences disk lifetimes and planet formation timescales. However, the turbulent properties of protoplanetary disks are poorly constrained observationally. Recent studies have found turbulent speeds smaller than what fully-developed MRI would produce (Flaherty et al.). However, existing studies assumed a constant CO/H2 ratio of 10-4 in locations where CO is not frozen-out or photo-dissociated. Our previous studies of evolving disk chemistry indicate that CO is depleted by incorporation into complex organic molecules well inside the freeze-out radius of CO. We consider the effects of this chemical depletion on measurements of turbulence. Simon et al. suggested that the ratio of the peak line flux to the flux at line center of the CO J = 3-2 transition is a reasonable diagnostic of turbulence, so we focus on that metric, while adding some analysis of the more complex effects on spatial distribution. We simulate the emission lines of CO based on chemical evolution models presented in Yu et al., and find that the peak-to-trough ratio changes as a function of time as CO is destroyed. Specifically, a CO-depleted disk with high turbulent velocity mimics the peak-to-trough ratios of a non-CO-depleted disk with lower turbulent velocity. We suggest that disk observers and modelers take into account the possibility of CO depletion when using line profiles or peak-to-trough ratios to constrain the degree of turbulence in disks. Assuming that {CO}/{{{H}}}2={10}-4 at all disk radii can lead to underestimates of turbulent speeds in the disk by at least 0.2 km s-1.
NASA Astrophysics Data System (ADS)
Nakano, M.; Hori, T.; Araki, E.; Kodaira, S.; Ide, S.
2017-12-01
Recent improvements of seismic and geodetic observations have revealed the existence of a new family of slow earthquakes occurring along or close to the plate boundary worldwide. In the viewpoint of the characteristic time scales, the slow earthquakes can be classified into several groups as low-frequency tremor or tectonic tremor (LFT) dominated in several hertz, very-low-frequency earthquake (VLFE) dominated in 10 to 100 s, and short- and long-term slow-slip event (SSE) with durations of days to years. In many cases, these slow earthquakes are accompanied with other types of slow events. However, the events occurring offshore, especially beneath the toe of accretionary prism, are poorly understood because of the difficulty to detect signals. Utilizing the data captured from oceanfloor observation networks which many efforts have recently been taken to develop is necessary to improve our understandings for these events. Here, we investigated CMT analysis of shallow VLFEs using data obtained from DONET oceanfloor observation networks along the Nankai trough, southwest of Japan. We found that shallow VLFEs have almost identical history of moment release with that of synchronous SSE which occurred at the same region recently found by Araki et al. (2017). VLFE sources show updip migrations during the activity, coincident with the migration of SSE source. From these findings we conclude that these slow events share the same fault slip, and VLFE represent high-frequency fluctuations of slip during SSE. This result imply that shallow SSE along the plate interface would have occurred in the background during the shallow VLFE activities repeatedly observed along the Nankai trough, but the SSE was not reported because of difficult detections.
Turco, R; Ummarino, D; Miele, E; Terrone, G; Del Giudice, E; Staiano, A
2015-10-01
Mechanism underlying the occurrence of Gastroesophageal reflux disease (GERD) in neurologically impaired children (NIC) is poorly understood. We sought to characterize, by Esophageal High Resolution Manometry (EHRM), alterations of esophageal motility associated with GERD in NIC and to compare with a group with a suspicion of GERD and normal psychomotor development (NDP). EHRM and multichannel intraluminal impedance/pH-metry (MII/pH) were conducted in 7 NIC and 9 patients with suspicion of GERD and NPD. Esophagogastric junction relaxation (EGJr), the presence/pressure troughs of the oesophageal segments, the distal contractile integral adjusted for esophageal length (DCIa) and the pressurization frontal velocity (PFV) were analyzed by EHRM. Three out of 7 NIC (42.8%) and 4 out of 9 patients with NPD (44.4%) resulted positive to MII/pH (p = 1). No statistical differences were observed for EGJr and PFV between NIC and NPD patients. DCIa was significantly lower in NIC subjects respect to NPD patients (p < 0.01). Comparing NIC with GERD and patients with GERD and NPD we found that third segment was absent in 2/3 (66,6 %) of NIC respect to NPD patients (p < 0.05) and that the third pressure trough was significantly lower in NIC respect to NPD patients (p < 0.05). There were no statistical differences with respect to the first and second pressure trough between NIC and NDP patients. NIC have esophageal motor dysfunction that can be detected by EHRM. Some esophageal manometric alterations could be predictive of GERD in NIC and could explain a different pathogenesis of GERD in NIC and in patients with NPD.
Pharmacokinetics of a combined oral contraceptive in obese and normal weight women
Westhoff, Carolyn L.; Torgal, Anupama H.; Mayeda, Elizabeth R.; Pike, Malcolm C.; Stanczyk, Frank Z.
2010-01-01
Background This study was conducted to compare oral contraceptive (OC) pharmacokinetics (PK) in normal weight (BMI 19.0-24.9) and obese (BMI 30.0-39.9) women. Study Design During the third week of the third cycle of OC use, we admitted 15 normal weight and 15 obese women for collection of 12 venous specimens over 24 h. Using RIA techniques, we measured levels of ethinyl estradiol (EE) and levonorgestrel (LNG). During the same cycle, women underwent twice-weekly sonography to assess ovarian follicular development and blood draws to measure endogenous estradiol (E2) and progesterone levels. Results Obese women had a lower area under the curve (AUC; 1077.2 pg*h/mL vs 1413.7 pg*h/mL) and lower maximum values (85.7 pg/mL vs 129.5 pg/mL) for EE than normal weight women (p = 0.04 and 0.01, respectively); EE trough levels were similar between BMI groups. The similar, but smaller, differences in their LNG levels for AUC and maximum values (Cmax) were not statistically significant. While peak values differed somewhat, the LNG trough levels were similar for obese and normal weight women (2.6 ng/mL and 2.5 ng/mL, respectively). Women with greater EE AUC had smaller follicular diameters (p = 0.05) and lower E2 levels (p = 0.04). While follicular diameters tended to be larger among obese women, these differences were not statistically significant. Conclusion OC hormone peak levels are lower among obese women compared to normal weight women, but their trough levels are similar. In this small study, the observed PK differences did not translate into more ovarian follicular activity among obese OC users. PMID:20472113