Science.gov

Sample records for optimal sites selection

  1. Optimizing Site Selection in Urban Areas in Northern Switzerland

    NASA Astrophysics Data System (ADS)

    Plenkers, K.; Kraft, T.; Bethmann, F.; Husen, S.; Schnellmann, M.

    2012-04-01

    There is a need to observe weak seismic events (M<2) in areas close to potential nuclear-waste repositories or nuclear power plants, in order to analyze the underlying seismo-tectonic processes and estimate their seismic hazard. We are therefore densifying the existing Swiss Digital Seismic Network in northern Switzerland by additional 20 stations. The new network that will be in operation by the end of 2012, aims at observing seismicity in northern Switzerland with a completeness of M_c=1.0 and a location error < 0.5 km in epicenter and < 2 km in focal depth. Monitoring of weak seismic events in this region is challenging, because the area of interest is densely populated and geology is dominated by the Swiss molasse basin. A optimal network-design and a thoughtful choice for station-sites is, therefore, mandatory. To help with decision making we developed a step-wise approach to find the optimum network configuration. Our approach is based on standard network optimization techniques regarding the localization error. As a new feature, our approach uses an ambient noise model to compute expected signal-to-noise ratios for a given site. The ambient noise model uses information on land use and major infrastructures such as highways and train lines. We ran a series of network optimizations with increasing number of stations until the requirements regarding localization error and magnitude of completeness are reached. The resulting network geometry serves as input for the site selection. Site selection is done by using a newly developed multi-step assessment-scheme that takes into account local noise level, geology, infrastructure, and costs necessary to realize the station. The assessment scheme is weighting the different parameters and the most promising sites are identified. In a first step, all potential sites are classified based on information from topographic maps and site inspection. In a second step, local noise conditions are measured at selected sites. We

  2. Optimizing landfill site selection by using land classification maps.

    PubMed

    Eskandari, M; Homaee, M; Mahmoodi, S; Pazira, E; Van Genuchten, M Th

    2015-05-01

    Municipal solid waste disposal is a major environmental concern throughout the world. Proper landfill siting involves many environmental, economic, technical, and sociocultural challenges. In this study, a new quantitative method for landfill siting that reduces the number of evaluation criteria, simplifies siting procedures, and enhances the utility of available land evaluation maps was proposed. The method is demonstrated by selecting a suitable landfill site near the city of Marvdasht in Iran. The approach involves two separate stages. First, necessary criteria for preliminary landfill siting using four constraints and eight factors were obtained from a land classification map initially prepared for irrigation purposes. Thereafter, the criteria were standardized using a rating approach and then weighted to obtain a suitability map for landfill siting, with ratings in a 0-1 domain and divided into five suitability classes. Results were almost identical to those obtained with a more traditional environmental landfill siting approach. Because of far fewer evaluation criteria, the proposed weighting method was much easier to implement while producing a more convincing database for landfill siting. The classification map also considered land productivity. In the second stage, the six best alternative sites were evaluated for final landfill siting using four additional criteria. Sensitivity analyses were furthermore conducted to assess the stability of the obtained ranking. Results indicate that the method provides a precise siting procedure that should convince all pertinent stakeholders.

  3. Site selection

    SciTech Connect

    Olsen, C.W.

    1983-07-01

    The conditions and criteria for selecting a site for a nuclear weapons test at the Nevada Test Site are summarized. Factors considered are: (1) scheduling of drill rigs, (2) scheduling of site preparation (dirt work, auger hole, surface casing, cementing), (3) schedule of event (when are drill hole data needed), (4) depth range of proposed W.P., (5) geologic structure (faults, Pz contact, etc.), (6) stratigraphy (alluvium, location of Grouse Canyon Tuff, etc.), (7) material properties (particularly montmorillonite and CO/sub 2/ content), (8) water table depth, (9) potential drilling problems (caving), (10) adjacent collapse craters and chimneys, (11) adjacent expended but uncollapsed sites, (12) adjacent post-shot or other small diameter holes, (13) adjacent stockpile emplacement holes, (14) adjacent planned events (including LANL), (15) projected needs of Test Program for various DOB's and operational separations, and (16) optimal use of NTS real estate.

  4. Optimal landing site selection based on safety index during planetary descent

    NASA Astrophysics Data System (ADS)

    Cui, Pingyuan; Ge, Dantong; Gao, Ai

    2017-03-01

    Landing safety is the prior concern in planetary exploration missions. With the development of precise landing technology, future missions require vehicles to land on places of great scientific interest which are usually surrounded by rocks and craters. In order to perform a safe landing, the vehicle should be capable of detecting hazards, estimating its fuel consumption as well as touchdown performance, and locating a safe spot to land. The landing site selection process can be treated as an optimization problem which, however, cannot be efficiently solved through traditional optimization methods due to its complexity. Hence, the paper proposes a synthetic landing area assessment criterion, safety index, as a solution of the problem, which selects the best landing site by assessing terrain safety, fuel consumption and touchdown performance during descent. The computation effort is cut down after reducing the selection scope and the optimal landing site is found through a quick one-dimensional search. A typical example based on the Mars Science Laboratory mission is simulated to demonstrate the capability of the method. It is proved that the proposed strategy manages to pick out a safe landing site for the mission effectively. The safety index can be applied in various planetary descent phases and provides reference for future mission designs.

  5. Optimal selection of on-site generation with combined heat andpower applications

    SciTech Connect

    Siddiqui, Afzal S.; Marnay, Chris; Bailey, Owen; HamachiLaCommare, Kristina

    2004-11-30

    While demand for electricity continues to grow, expansion of the traditional electricity supply system, or macrogrid, is constrained and is unlikely to keep pace with the growing thirst western economies have for electricity. Furthermore, no compelling case has been made that perpetual improvement in the overall power quality and reliability (PQR)delivered is technically possible or economically desirable. An alternative path to providing high PQR for sensitive loads would generate close to them in microgrids, such as the Consortium for Electricity Reliability Technology Solutions (CERTS) Microgrid. Distributed generation would alleviate the pressure for endless improvement in macrogrid PQR and might allow the establishment of a sounder economically based level of universal grid service. Energy conversion from available fuels to electricity close to loads can also provide combined heat and power (CHP) opportunities that can significantly improve the economics of small-scale on-site power generation, especially in hot climates when the waste heat serves absorption cycle cooling equipment that displaces expensive on-peak electricity. An optimization model, the Distributed Energy Resources Customer Adoption Model (DER-CAM), developed at Berkeley Lab identifies the energy bill minimizing combination of on-site generation and heat recovery equipment for sites, given their electricity and heat requirements, the tariffs they face, and a menu of available equipment. DER-CAM is used to conduct a systemic energy analysis of a southern California naval base building and demonstrates atypical current economic on-site power opportunity. Results achieve cost reductions of about 15 percent with DER, depending on the tariff.Furthermore, almost all of the energy is provided on-site, indicating that modest cost savings can be achieved when the microgrid is free to select distributed generation and heat recovery equipment in order to minimize its over all costs.

  6. Using maximum entropy modeling for optimal selection of sampling sites for monitoring networks

    USGS Publications Warehouse

    Stohlgren, Thomas J.; Kumar, Sunil; Barnett, David T.; Evangelista, Paul H.

    2011-01-01

    Environmental monitoring programs must efficiently describe state shifts. We propose using maximum entropy modeling to select dissimilar sampling sites to capture environmental variability at low cost, and demonstrate a specific application: sample site selection for the Central Plains domain (453,490 km2) of the National Ecological Observatory Network (NEON). We relied on four environmental factors: mean annual temperature and precipitation, elevation, and vegetation type. A “sample site” was defined as a 20 km × 20 km area (equal to NEON’s airborne observation platform [AOP] footprint), within which each 1 km2 cell was evaluated for each environmental factor. After each model run, the most environmentally dissimilar site was selected from all potential sample sites. The iterative selection of eight sites captured approximately 80% of the environmental envelope of the domain, an improvement over stratified random sampling and simple random designs for sample site selection. This approach can be widely used for cost-efficient selection of survey and monitoring sites.

  7. Optimizing nest survival and female survival: Consequences of nest site selection for Canada Geese

    USGS Publications Warehouse

    Miller, David A.; Grand, J.B.; Fondell, T.F.; Anthony, R. Michael

    2007-01-01

    We examined the relationship between attributes of nest sites used by Canada Geese (Branta canadensis) in the Copper River Delta, Alaska, and patterns in nest and female survival. We aimed to determine whether nest site attributes related to nest and female survival differed and whether nest site attributes related to nest survival changed within and among years. Nest site attributes that we examined included vegetation at and surrounding the nest, as well as associations with other nesting birds. Optimal nest site characteristics were different depending on whether nest survival or female survival was examined. Prior to 25 May, the odds of daily survival for nests in tall shrubs and on islands were 2.92 and 2.26 times greater, respectively, than for nests in short shrub sites. Bald Eagles (Halieaeetus leucocephalus) are the major predator during the early breeding season and their behavior was likely important in determining this pattern. After 25 May, when eagle predation is limited due to the availability of alternative prey, no differences in nest survival among the nest site types were found. In addition, nest survival was positively related to the density of other Canada Goose nests near the nest site. Although the number of detected mortalities for females was relatively low, a clear pattern was found, with mortality three times more likely at nest sites dominated by high shrub density within 50 m than at open sites dominated by low shrub density. The negative relationship of nest concealment and adult survival is consistent with that found in other studies of ground-nesting birds. Physical barriers that limited access to nest sites by predators and sites that allowed for early detection of predators were important characteristics of nest site quality for Canada Geese and nest site quality shifted within seasons, likely as a result of shifting predator-prey interactions.

  8. Optimal site selection for a high-resolution ice core record in East Antarctica

    NASA Astrophysics Data System (ADS)

    Vance, Tessa R.; Roberts, Jason L.; Moy, Andrew D.; Curran, Mark A. J.; Tozer, Carly R.; Gallant, Ailie J. E.; Abram, Nerilie J.; van Ommen, Tas D.; Young, Duncan A.; Grima, Cyril; Blankenship, Don D.; Siegert, Martin J.

    2016-03-01

    Ice cores provide some of the best-dated and most comprehensive proxy records, as they yield a vast and growing array of proxy indicators. Selecting a site for ice core drilling is nonetheless challenging, as the assessment of potential new sites needs to consider a variety of factors. Here, we demonstrate a systematic approach to site selection for a new East Antarctic high-resolution ice core record. Specifically, seven criteria are considered: (1) 2000-year-old ice at 300 m depth; (2) above 1000 m elevation; (3) a minimum accumulation rate of 250 mm years-1 IE (ice equivalent); (4) minimal surface reworking to preserve the deposited climate signal; (5) a site with minimal displacement or elevation change in ice at 300 m depth; (6) a strong teleconnection to midlatitude climate; and (7) an appropriately complementary relationship to the existing Law Dome record (a high-resolution record in East Antarctica). Once assessment of these physical characteristics identified promising regions, logistical considerations (for site access and ice core retrieval) were briefly considered. We use Antarctic surface mass balance syntheses, along with ground-truthing of satellite data by airborne radar surveys to produce all-of-Antarctica maps of surface roughness, age at specified depth, elevation and displacement change, and surface air temperature correlations to pinpoint promising locations. We also use the European Centre for Medium-Range Weather Forecast ERA 20th Century reanalysis (ERA-20C) to ensure that a site complementary to the Law Dome record is selected. We find three promising sites in the Indian Ocean sector of East Antarctica in the coastal zone from Enderby Land to the Ingrid Christensen Coast (50-100° E). Although we focus on East Antarctica for a new ice core site, the methodology is more generally applicable, and we include key parameters for all of Antarctica which may be useful for ice core site selection elsewhere and/or for other purposes.

  9. Optimal site selection for a high resolution ice core record in East Antarctica

    NASA Astrophysics Data System (ADS)

    Vance, T.; Roberts, J.; Moy, A.; Curran, M.; Tozer, C.; Gallant, A.; Abram, N.; van Ommen, T.; Young, D.; Grima, C.; Blankenship, D.; Siegert, M.

    2015-11-01

    Ice cores provide some of the best dated and most comprehensive proxy records, as they yield a vast and growing array of proxy indicators. Selecting a site for ice core drilling is nonetheless challenging, as the assessment of potential new sites needs to consider a variety of factors. Here, we demonstrate a systematic approach to site selection for a new East Antarctic high resolution ice core record. Specifically, seven criteria are considered: (1) 2000 year old ice at 300 m depth, (2) above 1000 m elevation, (3) a minimum accumulation rate of 250 mm yr-1 IE, (4) minimal surface re-working to preserve the deposited climate signal, (5) a site with minimal displacement or elevation change of ice at 300 m depth, (6) a strong teleconnection to mid-latitude climate and (7) an appropriately complementary relationship to the existing Law Dome record (a high resolution record in East Antarctica). Once assessment of these physical characteristics identified promising regions, logistical considerations (for site access and ice core retrieval) were briefly considered. We use Antarctic surface mass balance syntheses, along with ground-truthing of satellite data by airborne radar surveys to produce all-of-Antarctica maps of surface roughness, age at specified depth, elevation and displacement change and surface air temperature correlations to pinpoint promising locations. We also use the European Centre for Medium-Range Weather Forecast ERA 20th Century reanalysis (ERA-20C) to ensure a site complementary to the Law Dome record is selected. We find three promising sites in the Indian Ocean sector of East Antarctica in the coastal zone from Enderby Land to the Ingrid Christensen Coast (50-100° E). Although we focus on East Antarctica for a new ice core site, the methodology is more generally applicable and we include key parameters for all of Antarctica which may be useful for ice core site selection elsewhere and/or for other purposes.

  10. Optimal Site Characterization and Selection Criteria for Oyster Restoration using Multicolinear Factorial Water Quality Approach

    NASA Astrophysics Data System (ADS)

    Yoon, J.

    2015-12-01

    Elevated levels of nutrient loadings have enriched the Chesapeake Bay estuaries and coastal waters via point and nonpoint sources and the atmosphere. Restoring oyster beds is considered a Best Management Practice (BMP) to improve the water quality as well as provide physical aquatic habitat and a healthier estuarine system. Efforts include declaring sanctuaries for brood-stocks, supplementing hard substrate on the bottom and aiding natural populations with the addition of hatchery-reared and disease-resistant stocks. An economic assessment suggests that restoring the ecological functions will improve water quality, stabilize shorelines, and establish a habitat for breeding grounds that outweighs the value of harvestable oyster production. Parametric factorial models were developed to investigate multicolinearities among in situ water quality and oyster restoration activities to evaluate posterior success rates upon multiple substrates, and physical, chemical, hydrological and biological site characteristics to systematically identify significant factors. Findings were then further utilized to identify the optimal sites for successful oyster restoration augmentable with Total Maximum Daily Loads (TMDLs) and BMPs. Factorial models evaluate the relationship among the dependent variable, oyster biomass, and treatments of temperature, salinity, total suspended solids, E. coli/Enterococci counts, depth, dissolved oxygen, chlorophyll a, nitrogen and phosphorus, and blocks consist of alternative substrates (oyster shells versus riprap, granite, cement, cinder blocks, limestone marl or combinations). Factorial model results were then compared to identify which combination of variables produces the highest posterior biomass of oysters. Developed Factorial model can facilitate maximizing the likelihood of successful oyster reef restoration in an effort to establish a healthier ecosystem and to improve overall estuarine water quality in the Chesapeake Bay estuaries.

  11. Selective pacing sites.

    PubMed

    Coppola, G; La Greca, C; Corrado, E; Ajello, L; Nogara, A; Ciaramitaro, G; Augugliaro, S; Novo, G; Novo, S; Assennato, P

    2015-04-01

    bundle fibrous area, higher pacing thresholds are required, causing accelerated battery depletion. For all these reasons, PHP could be considered an important alternative to DHBP, to be used on a large scale. Finally, bifocal pacing in CRT candidates, provides better acute hemodynamic performance than RVA pacing, derived from a minor intra- and interventricular dyssynchrony, expressed also by the QRS shortening. Then, bifocal pacing could be taken into account when RVA pacing is likely to be the origin of serious mechanical and electrical dyssynchrony or when CRT is contraindicated or technically impossible. So, whatever chosen as selective pacing site, you must look also at safety, effectiveness and necessary equipment for an optimal pacing site.

  12. Selecting an optimal number of binding site waters to improve virtual screening enrichments against the adenosine A2A receptor.

    PubMed

    Lenselink, Eelke B; Beuming, Thijs; Sherman, Woody; van Vlijmen, Herman W T; IJzerman, Adriaan P

    2014-06-23

    A major challenge in structure-based virtual screening (VS) involves the treatment of explicit water molecules during docking in order to improve the enrichment of active compounds over decoys. Here we have investigated this in the context of the adenosine A2A receptor, where water molecules have previously been shown to be important for achieving high enrichment rates with docking, and where the positions of some binding site waters are known from a high-resolution crystal structure. The effect of these waters (both their presence and orientations) on VS enrichment was assessed using a carefully curated set of 299 high affinity A2A antagonists and 17,337 decoys. We show that including certain crystal waters greatly improves VS enrichment and that optimization of water hydrogen positions is needed in order to achieve the best results. We also show that waters derived from a molecular dynamics simulation - without any knowledge of crystallographic waters - can improve enrichments to a similar degree as the crystallographic waters, which makes this strategy applicable to structures without experimental knowledge of water positions. Finally, we used decision trees to select an ensemble of structures with different water molecule positions and orientations that outperforms any single structure with water molecules. The approach presented here is validated against independent test sets of A2A receptor antagonists and decoys from the literature. In general, this water optimization strategy could be applied to any target with waters-mediated protein-ligand interactions.

  13. Optimal site selection for sitting a solar park using multi-criteria decision analysis and geographical information systems

    NASA Astrophysics Data System (ADS)

    Georgiou, Andreas; Skarlatos, Dimitrios

    2016-07-01

    Among the renewable power sources, solar power is rapidly becoming popular because it is inexhaustible, clean, and dependable. It has also become more efficient since the power conversion efficiency of photovoltaic solar cells has increased. Following these trends, solar power will become more affordable in years to come and considerable investments are to be expected. Despite the size of solar plants, the sitting procedure is a crucial factor for their efficiency and financial viability. Many aspects influence such a decision: legal, environmental, technical, and financial to name a few. This paper describes a general integrated framework to evaluate land suitability for the optimal placement of photovoltaic solar power plants, which is based on a combination of a geographic information system (GIS), remote sensing techniques, and multi-criteria decision-making methods. An application of the proposed framework for the Limassol district in Cyprus is further illustrated. The combination of a GIS and multi-criteria methods produces an excellent analysis tool that creates an extensive database of spatial and non-spatial data, which will be used to simplify problems as well as solve and promote the use of multiple criteria. A set of environmental, economic, social, and technical constrains, based on recent Cypriot legislation, European's Union policies, and expert advice, identifies the potential sites for solar park installation. The pairwise comparison method in the context of the analytic hierarchy process (AHP) is applied to estimate the criteria weights in order to establish their relative importance in site evaluation. In addition, four different methods to combine information layers and check their sensitivity were used. The first considered all the criteria as being equally important and assigned them equal weight, whereas the others grouped the criteria and graded them according to their objective perceived importance. The overall suitability of the study

  14. Site selection for Mars exobiology.

    PubMed

    Farmer, J; Des Marais, D; Greeley, R; Landheim, R; Klein, H

    1995-03-01

    The selection of sites on Mars that have a high priority for exobiological research is fundamental for planning future exploration. The most immediate need is to identify targets for high resolution orbital imaging during the Mars Observer and Mars '94/'96 missions that can be used to refine site priorities for surface exploration. We present an objective approach to site selection whereby individual sites are selected and scored, based on the presence of key geological features which indicate high priority environments. Prime sites are those that show evidence for the prolonged activity of liquid water and which have sedimentary deposits that are likely to have accumulated in environments favorable for life. High priority areas include fluvio-lacustrine (stream-fed lake systems), springs, and periglacial environments. Sites where mineralization may have occurred in the presence of organisms (e.g. springs) are given high priority in the search for a fossil record on Mars. A systematic review of Viking data for 83 sites in the Mars Landing Site Catalog resulted in the selection of 13 as being of exobiological interest. The descriptions of these sites were expanded to address exobiological concerns. An additional five sites were identified for inclusion in the second edition of the MLSC. We plan to broaden our site selection activities to include a systematic global reconnaissance of Mars using Viking data, and will continue to refine site priorities for exobiological research based on data from future missions in order to define strategies for surface exploration.

  15. Site selection for Mars exobiology

    NASA Technical Reports Server (NTRS)

    Farmer, J.; Des Marais, D.; Greeley, R.; Landheim, R.; Klein, H.

    1995-01-01

    The selection of sites on Mars that have a high priority for exobiological research is fundamental for planning future exploration. The most immediate need is to identify targets for high resolution orbital imaging during the Mars Observer and Mars '94/'96 missions that can be used to refined site priorities for surface exploration. We present an objective approach to site selection whereby individual sites are selected and scored, based on the presence of key geological features which indicate high priority environments. Prime sites are those that show evidence for the prolonged activity of liquid water and which have sedimentary deposits that are likely to have accumulated in environments favorable for life. High priority areas include fluvio-lacustrine (stream-fed lake systems), springs, and periglacial environments. Sites where mineralization may have occurred in the presence of organisms (e.g. springs) are given high priority in the search for a fossil record on Mars. A systematic review of Viking data for 83 sites in the Mars Landing Site Catalog (MLSC) resulted in the selection of 13 as being of exobiological interest. The descriptions of these sites were expanded to address exobiological concerns. An additional five sites were identified for inclusion in the second edition of the MLSC. We plan to broaden our site selection activities to include a systematic global reconnaissance of Mars using Viking data, and will continue to refine site priorities for exobiological research based on data from future missions in order to define strategies for surface exploration.

  16. Jamestown: A Site Selection Exercise.

    ERIC Educational Resources Information Center

    Victory, James

    1982-01-01

    Describes a secondary, U.S. history simulation of the settlement of the Jamestown colony. Students are provided with a map and asked to decide where the fort and colony should be set up. They must state reasons for selecting a particular site and reasons for rejecting others. (AM)

  17. SCHOOL SITES. SELECTION AND DEVELOPMENT.

    ERIC Educational Resources Information Center

    REIDA, G.W.

    CERTAIN CRITICAL CRITERIA SHOULD BE CONSIDERED IN SELECTING THE SCHOOL SITE. IMPORTANT IS THE STUDY OF SUCH FACTORS AS PRESENT AND PROJECTED PUPIL POPULATION, THE SCHOOL MASTER PLAN, MAIN THOROUGHFARES, DWELLINGS, LAND USE, SOILS, (SHOWN BY SERVICE MAPS), EXISTING SCHOOL FACILITIES AND ATTENDANCE, BOUNDARIES, UTILITY SERVICES AND FLOOD CONTROLS.…

  18. Viking site selection and certification

    NASA Technical Reports Server (NTRS)

    Masursky, H.; Crabill, N. L.

    1981-01-01

    The landing site selection and certification effort for the Viking mission to Mars is reviewed from the premission phase through the acquisition of data and decisions during mission operations and the immediate postlanding evaluation. The utility and limitations of the orbital television and infrared data and ground based radar observation of candidate and actual landing sites are evaluated. Additional instruments and types of observations which would have been useful include higher resolution cameras, radar altimeters, and terrain hazard avoidance capability in the landing system. Suggestions based on this experience that might be applied to future missions are included.

  19. Optimization Under Uncertainty of Site-Specific Turbine Configurations

    NASA Astrophysics Data System (ADS)

    Quick, J.; Dykes, K.; Graf, P.; Zahle, F.

    2016-09-01

    Uncertainty affects many aspects of wind energy plant performance and cost. In this study, we explore opportunities for site-specific turbine configuration optimization that accounts for uncertainty in the wind resource. As a demonstration, a simple empirical model for wind plant cost of energy is used in an optimization under uncertainty to examine how different risk appetites affect the optimal selection of a turbine configuration for sites of different wind resource profiles. If there is unusually high uncertainty in the site wind resource, the optimal turbine configuration diverges from the deterministic case and a generally more conservative design is obtained with increasing risk aversion on the part of the designer.

  20. Optimization Under Uncertainty of Site-Specific Turbine Configurations

    SciTech Connect

    Quick, J.; Dykes, K.; Graf, P.; Zahle, F.

    2016-10-03

    Uncertainty affects many aspects of wind energy plant performance and cost. In this study, we explore opportunities for site-specific turbine configuration optimization that accounts for uncertainty in the wind resource. As a demonstration, a simple empirical model for wind plant cost of energy is used in an optimization under uncertainty to examine how different risk appetites affect the optimal selection of a turbine configuration for sites of different wind resource profiles. Lastly, if there is unusually high uncertainty in the site wind resource, the optimal turbine configuration diverges from the deterministic case and a generally more conservative design is obtained with increasing risk aversion on the part of the designer.

  1. Optimization under Uncertainty of Site-Specific Turbine Configurations: Preprint

    SciTech Connect

    Quick, Julian; Dykes, Katherine; Graf, Peter; Zahle, Frederik

    2016-11-01

    Uncertainty affects many aspects of wind energy plant performance and cost. In this study, we explore opportunities for site-specific turbine configuration optimization that accounts for uncertainty in the wind resource. As a demonstration, a simple empirical model for wind plant cost of energy is used in an optimization under uncertainty to examine how different risk appetites affect the optimal selection of a turbine configuration for sites of different wind resource profiles. If there is unusually high uncertainty in the site wind resource, the optimal turbine configuration diverges from the deterministic case and a generally more conservative design is obtained with increasing risk aversion on the part of the designer.

  2. How to Optimize Your Web Site

    ERIC Educational Resources Information Center

    Dysart, Joe

    2008-01-01

    Given Google's growing market share--69% of all searches by the close of 2007--it's absolutely critical for any school on the Web to ensure its site is Google-friendly. A Google-optimized site ensures that students and parents can quickly find one's district on the Web even if they don't know the address. Plus, good search optimization simply…

  3. SLS Test Stand Site Selection

    NASA Technical Reports Server (NTRS)

    Crowe, Kathryn; Williams, Michael

    2015-01-01

    Test site selection is a critical element of the design, development and production of a new system. With the advent of the new Space Launch System (SLS), the National Aeronautics and Space Administration (NASA) had a number of test site selection decisions that needed to be made early enough in the Program to support the planned Launch Readiness Date (LRD). This case study focuses on decisions that needed to be made in 2011 and 2012 in preparation for the April 2013 DPMC decision about where to execute the Main Propulsion Test that is commonly referred to as "Green Run." Those decisions relied upon cooperative analysis between the Program, the Test Lab and Center Operations. The SLS is a human spaceflight vehicle designed to carry a crew farther into space than humans have previously flown. The vehicle consists of four parts: the crew capsule, the upper stage, the core stage, and the first stage solid rocket boosters. The crew capsule carries the astronauts, while the upper stage, the core stage, and solid rocket boosters provide thrust for the vehicle. In other words, the stages provide the "lift" part of the lift vehicle. In conjunction with the solid rocket boosters, the core stage provides the initial "get-off-the-ground" thrust to the vehicle. The ignition of the four core stage engines and two solid rocket boosters is the first step in the launch portion of the mission. The solid rocket boosters burn out after about 2 minutes of flight, and are then jettisoned. The core stage provides thrust until the vehicle reaches a specific altitude and speed, at which point the core stage is shut off and jettisoned, and the upper stage provides vehicle thrust for subsequent mission trajectories. The integrated core stage primarily consists of a liquid oxygen tank, a liquid hydrogen tank, and the four core stage engines. For the SLS program, four RS-25 engines were selected as the four core stage engines. The RS-25 engine is the same engine that was used for Space

  4. Differential-Evolution algorithm based optimization for the site selection of groundwater production wells with the consideration of the vulnerability concept

    NASA Astrophysics Data System (ADS)

    Elçi, Alper; Ayvaz, M. Tamer

    2014-04-01

    The objective of this study is to present an optimization approach to determine locations of new groundwater production wells, where groundwater is relatively less susceptible to groundwater contamination (i.e. more likely to obtain clean groundwater), the pumping rate is maximum or the cost of well installation and operation is minimum for a prescribed set of constraints. The approach also finds locations that are in suitable areas for new groundwater exploration with respect to land use. A regional-scale groundwater flow model is coupled with a hybrid optimization model that uses the Differential Evolution (DE) algorithm and the Broyden-Fletcher-Goldfarb-Shanno (BFGS) method as the global and local optimizers, respectively. Several constraints such as the depth to the water table, total well length and the restriction of seawater intrusion are considered in the optimization process. The optimization problem can be formulated either as the maximization of the pumping rate or as the minimization of total costs of well installation and pumping operation from existing and new wells. Pumping rates of existing wells that are prone to seawater intrusion are optimized to prevent groundwater flux from the shoreline towards these wells. The proposed simulation-optimization model is demonstrated on an existing groundwater flow model for the Tahtalı watershed in Izmir-Turkey. The model identifies for the demonstration study locations and pumping rates for up to four new wells and one new well in the cost minimization and maximization problem, respectively. All new well locations in the optimized solution coincide with areas of relatively low groundwater vulnerability. Considering all solutions of the demonstration study, groundwater vulnerability indices for new well locations range from 29.64 to 40.48 (on a scale of 0-100, where 100 indicates high vulnerability). All identified wells are located relatively close to each other. This implies that the method pinpoints the

  5. Optimize facility-siting evaluations

    SciTech Connect

    Wallace, S.J.; Hunter, B.L. )

    1994-05-01

    Case histories show how to combine hazard-evaluation tools that effectively assess facility siting. Depending on the complexity of the process and equipment, more than one tool and hazard analysis method (HAZOP, FMEA, etc.) may be needed. Operating facilities must use all possible resources such as checklists, plot plans/elevation drawings, models, tours, etc., when performing a process hazard analysis (PHA). More importantly, the facility-siting evaluation techniques must be cost-effective, user friendly and results oriented. Facility siting, mandated by federal regulation (OSHA 1910.119), calls for a how to methodology. Because it is an interpretation of risk due to location, facility siting has no single correct method. Operating companies must equip their PHA teams with an optimum combination of hazard-evaluation methods that address actual process consequences and their effects on worker safety. This paper discusses the use of these resources in hazard analysis, then illustrates the methods with several case histories from a refinery, a papermill, and a manufacturing facility.

  6. Anterior wrist and medial malleolus: the optimal sites for tissue selection in electric death through hand-to-foot circuit pathway.

    PubMed

    Xu, Guangtao; Su, Ruibing; Lv, Junyao; Lai, Xiaoping; Li, Xianxian; Wu, Jiayan; Hu, Bo; Xu, Long; Shen, Ruilin; Gu, Jiang; Yu, Xiaojun

    2017-03-01

    Specific morphological changes may be absent in some cases of electrocution shocked by the voltage of 220 V or lower. In this study, we attempted to demonstrate that the anterior wrist and medial malleolus were the optimal sites with promising and significant changes in electric death through the hand-to-foot circuit pathway. We established an electric shock rat model and observed histopathologic changes in the anterior wrist and medial malleolus. The results showed that the current intensities in the left anterior wrist and right medial malleolus were remarkably higher than those in the other sites, and the nuclei long/short (L/S) axis ratios of the arterial endotheliocyte and the skeletal muscle cell in these two areas were significantly higher than those in other parts of the body. These findings suggested that the anterior wrist and/or medial malleolus soft tissues as the narrowest parts of the limbs could be used as promising and useful sites for the assessment of electrical shock death, especially in forensic pathologic evaluation.

  7. Criteria for School Site Selection.

    ERIC Educational Resources Information Center

    Stanford Univ., CA.

    An outline of the factors and conditions affecting the desirability of a specific building site. The primary factor headings are--(1) availability, (2) location, (3) environment, (4) accessibility, (5) size, (6) shape, (7) topography, (8) acquisition, (9) cost of land, (10) soil condition, (11) sub-surface condition, (12) site preparation, (13)…

  8. NGNP Site Selection Status Report

    SciTech Connect

    Mark Holbrook

    2006-12-01

    This report provides an overview of the Nuclear Regulatory Commission (NRC) licensing process, the preliminary site activities that have taken place in the current fiscal year (FY-06), and the site-related plans for FY-07. The NRC maintains oversight of the construction and operation of a facility throughout its lifetime to assure compliance with the Commission's regulations for the protection of public health and safety, the common defense and security, and the environment. To implement this process, all nuclear power plant applications must undergo a safety review, an environmental review, and antitrust review by the NRC.

  9. Optimization Under Uncertainty of Site-Specific Turbine Configurations

    DOE PAGES

    Quick, J.; Dykes, K.; Graf, P.; ...

    2016-10-03

    Uncertainty affects many aspects of wind energy plant performance and cost. In this study, we explore opportunities for site-specific turbine configuration optimization that accounts for uncertainty in the wind resource. As a demonstration, a simple empirical model for wind plant cost of energy is used in an optimization under uncertainty to examine how different risk appetites affect the optimal selection of a turbine configuration for sites of different wind resource profiles. Lastly, if there is unusually high uncertainty in the site wind resource, the optimal turbine configuration diverges from the deterministic case and a generally more conservative design is obtainedmore » with increasing risk aversion on the part of the designer.« less

  10. Chemical site-selective prenylation of proteins.

    PubMed

    Gamblin, David P; van Kasteren, Sander; Bernardes, Gonçalo J L; Chalker, Justin M; Oldham, Neil J; Fairbanks, Antony J; Davis, Benjamin G

    2008-06-01

    A direct thionation procedure allows conversion of allylic alcohols into the corresponding thiols, the products of which are immediately compatible with one-pot site-selective selenenyl sulfide mediated protein conjugation.

  11. Strategy for selecting Mars Pathfinder landing sites

    NASA Technical Reports Server (NTRS)

    Greeley, Ronald; Kuzmin, Ruslin O.

    1994-01-01

    A strategy for Pathfinder site selection must be developed that is fundamentally different from most previous considerations. At least two approaches can be identified. In one approach, the objective is to select a site representing a key geologic unit on Mars, i.e., a unit that is widespread, easily recognized, and used frequently as a datum in various investigations. The second approach is to select a site that potentially affords access to a wide variety of rock types. Because rover range is limited, rocks from a variety of sources must be assembled in a small area for sampling. Regardless of the approach taken in site selection, the Pathfinder site should include eolian deposits and provisions should be made to obtain measurements on soils. A recommended approach for selecting the Mars Pathfinder landing site is to identify a deltaic deposit, composed of sediments derived from sources of various ages and geologic units that shows evidence of eolian activity. The site should be located as close as possible to the part of the outwash where rapid deposition occurred because the likelihood of 'sorting' by size and composition increases with distance, decreasing the probability of heterogeneity. In addition, it is recommended that field operation tests be conducted to gain experience and insight into conducting science with Pathfinder.

  12. Birds of the Hanford site: nest site selection

    SciTech Connect

    Rickard, W.H.; Fitzner, R.E.

    1983-03-01

    At least 62 species of birds regularly nest on the 1400 km/sup 2/ Hanford Site in the semi-arid interior of southcentral Washington. Birds showed nesting preferences for different kinds of vegetation, special natural landscape features and certain kinds of man-made structures. Vegetational nest site preferences were categorized as shrubsteppe, natural coppice, planted trees and cattail-reed marsh. The nonvegetational nest-site preferences were categorized as cliff, rock talus, riverine islands and industrial structures. Natural coppice vegetation was preferred by colorful passerine birds. Planted trees were selected by raptors, crows, ravens, herons and magpies. Shrubsteppe plant communities occupy most of the land area of the Hanford Site; only thirteen species of birds chose to nest in them. Nest-site selection by birds can be used for wildlife mitigation practices associated with the siting, construction and operation of energy related industries on the Hanford Site and in other undeveloped semi-arid regions in the western United States. 22 references, 5 figures, 2 tables.

  13. Lunar resource evaluation and mine site selection

    NASA Technical Reports Server (NTRS)

    Bence, A. Edward

    1992-01-01

    Two scenarios in this evaluation of lunar mineral resources and the selection of possible mining and processing sites are considered. The first scenario assumes that no new surface or near-surface data will be available before site selection (presumably one of the Apollo sites). The second scenario assumes that additional surface geology data will have been obtained by a lunar orbiter mission, an unmanned sample return mission (or missions), and followup manned missions. Regardless of the scenario, once a potentially favorable mine site has been identified, a minimum amount of fundamental data is needed to assess the resources at that site and to evaluate its suitability for mining and downstream processing. Since much of the required data depends on the target mineral(s), information on the resource, its beneficiation, and the refining, smelting, and fabricating processes must be factored into the evaluation. The annual capacity and producing lifetime of the mine and its associated processing plant must be estimated before the resource reserves can be assessed. The available market for the product largely determines the capacity and lifetime of the mine. The Apollo 17 site is described as a possible mining site. The use of new sites is briefly addressed.

  14. The Viking landing sites: Selection and certification

    USGS Publications Warehouse

    Masursky, H.; Crabill, N.L.

    1976-01-01

    During the past several years the Viking project developed plans to use Viking orbiter instruments and Earth-based radar to certify the suitability of the landing sites selected as the safest and most scientifically rewarding using Mariner 9 data. During June and July 1976, the Earth-based radar and orbital spacecraft observations of some of the prime and backup sites were completed. The results of these combined observations indicated that the Viking 1 prime landing area in the Chryse region of Mars is geologically varied and possibly more hazardous than expected, and was not certifiable as a site for the Viking 1 landing. Consequently, the site certification effort had to be drastically modified and lengthened to search for a site that might be safe enough to attempt to land. The selected site considered at 47.5??W,22.4??N represented a compromise between desirable characteristics observed with visual images and those inferred from Earth-based radar. It lies in the Chryse region about 900 kilometers northwest of the original site. Viking 1 landed successfully at this site on 20 July 1976.

  15. Site-optimization of wind turbine generators

    SciTech Connect

    Wolff, T.J. de; Thillerup, J.

    1997-12-31

    The Danish Company Nordtank is one of the pioneers within the wind turbine industry. Since 1981 Nordtank has installed worldwide more than 2500 wind turbine generators with a total name plate capacity that is exceeding 450 MW. The opening up of new and widely divergent markets has demanded an extremely flexible approach towards wind turbine construction. The Nordtank product range has expanded considerable in recent years, with the main objective to develop wind energy conversion machines that can run profitable in any given case. This paper will describe site optimization of Nordtank wind turbines. Nordtank has developed a flexible design concept for its WTGs in the 500/750 kW range, in order to offer the optimal WTG solution for any given site and wind regime. Through this flexible design, the 500/750 turbine line can adjust the rotor diameter, tower height and many other components to optimally fit the turbine to each specific project. This design philosophy will be illustrated with some case histories of recently completed projects.

  16. A perspective of landing-site selection

    NASA Technical Reports Server (NTRS)

    Moore, Henry J.

    1994-01-01

    The problems that now confront Mars Pathfinder are much the same as those that confronted Viking, but more and better information exists today. Like Viking, Mars Pathfinder must select a landing site compatible with lander and rover designs as evidenced by available data (Viking images, radar and thermal observations, albedo and color observations, visible-infrared spectra, etc.). Most regions at low elevations probably contain favorable sites, but some sites at low elevations with weak quasispecular echoes and low thermal inertias may be unfavorable.

  17. Site Optimization Tracker: Crossley Farm Superfund Site, Hereford and Washington Townships, Berks County, Pennsylvania

    EPA Pesticide Factsheets

    Pilot Region-Based Optimization Program for Fund-Lead Sites in EPA Region 3. Site Optimization Tracking information for Crossley Farm Superfund Site, Hereford and Washington Townships, Berks County, Pennsylvania.

  18. 32 CFR 644.22 - Site selection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... HANDBOOK Project Planning Military (army and Air Force) and Other Federal Agencies § 644.22 Site selection... projects and available lands under the control of other departments and agencies, suitable for the desired... Engineer to prepare a Real Estate Planning Report or Real Estate Summary, making reference to the...

  19. 32 CFR 644.22 - Site selection.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... HANDBOOK Project Planning Military (army and Air Force) and Other Federal Agencies § 644.22 Site selection... projects and available lands under the control of other departments and agencies, suitable for the desired... Engineer to prepare a Real Estate Planning Report or Real Estate Summary, making reference to the...

  20. 40 CFR 240.202 - Site selection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Site selection. 240.202 Section 240.202 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES GUIDELINES FOR THE THERMAL PROCESSING OF SOLID WASTES Requirements and Recommended Procedures § 240.202...

  1. Crustal dynamics project site selection criteria

    NASA Technical Reports Server (NTRS)

    Allenby, R.

    1983-01-01

    The criteria for selecting site locations and constructing observing pads and monuments for the Mobile VLB1 and the satellite laser ranging systems used in the NASA/GSFC Crustal Dynamics Project are discussed. Gross system characteristics (size, shape, weight, power requirement, foot prints, etc.) are given for the Moblas, MV-1 through 3, TLRS-1 through 4 and Series instruments.

  2. Replacement Power Facility site selection report

    SciTech Connect

    Wike, L.D.; Toole, G.L.; Specht, W.L.

    1992-06-01

    The Department of Energy (DOE) has proposed the construction and operation of a Replacement Power Facility (RPF) for supplementing and replacing existing sources of steam and possibly electricity at the Savannah River Site (SRS). DOE is preparing an Environmental Impact Statement (EIS) for this project As part of the impact analysis of the proposed action, the EIS will include a detailed description of the environment where the RPF will be constructed. This description must be specific to the recommended site at SRS, which contains more than 300 square miles of land including streams, lakes, impoundments, wetlands, and upland areas. A formal site-selection process was designed and implemented to identify the preferred RPF site.

  3. Texas site selection and licensing status

    SciTech Connect

    Avant, R.V. Jr.

    1989-11-01

    Texas has identified a potential site in Hudspeth County in far West Texas near the town of Fort Hancock. Over the past year the Texas Low-Level Radioactive Waste Disposal Authority has been conducting detailed geology, hydrology, meteorology, soils, and flora and fauna evaluations. An authorization by the Board of Directors of the Authority to proceed with a license application, assuming that the detailed evaluation indicates that the site is suitable, is expected by September. A prototype license has been prepared in anticipation of the order to proceed with licensing, and the formal license application is expected to be submitted to the Texas Department of Health-Bureau of Radiation Control in December, meeting the license application milestone. Although site selection processes in all siting areas across the country have experienced organized opposition, El Paso County has funded a particularly well-organized, well-financed program to legally and technically stop consideration of the Fort Hancock site prior to the licensing process. Many procedural, regulatory, and technical issues have been raised which have required responses from the Authority in order to proceed with licensing. This has provided a unique perspective of what to expect from well-organized opposition at the licensing stage. This paper presents an update on the Texas siting activity with detailed information on the site evaluation and license application. Experience of dealing with issues raised by opposition relating to NRC guidelines and rules is also discussed.

  4. Optimal selection of biochars for remediating metals ...

    EPA Pesticide Factsheets

    Approximately 500,000 abandoned mines across the U.S. pose a considerable, pervasive risk to human health and the environment due to possible exposure to the residuals of heavy metal extraction. Historically, a variety of chemical and biological methods have been used to reduce the bioavailability of the metals at mine sites. Biochar with its potential to complex and immobilize heavy metals, is an emerging alternative for reducing bioavailability. Furthermore, biochar has been reported to improve soil conditions for plant growth and can be used for promoting the establishment of a soil-stabilizing native plant community to reduce offsite movement of metal-laden waste materials. Because biochar properties depend upon feedstock selection, pyrolysis production conditions, and activation procedures used, they can be designed to meet specific remediation needs. As a result biochar with specific properties can be produced to correspond to specific soil remediation situations. However, techniques are needed to optimally match biochar characteristics with metals contaminated soils to effectively reduce metal bioavailability. Here we present experimental results used to develop a generalized method for evaluating the ability of biochar to reduce metals in mine spoil soil from an abandoned Cu and Zn mine. Thirty-eight biochars were produced from approximately 20 different feedstocks and produced via slow pyrolysis or gasification, and were allowed to react with a f

  5. Site Selection for Mars Exopaleontology in 2001

    NASA Technical Reports Server (NTRS)

    Farmer, Jack

    1998-01-01

    floors of some impact craters on Mars, such as "White Rock" and Bequeral Crater (see Oxia Palus NE, Site 148), have floor deposits that could be evaporites, inclusive of carbonates. Evaporite minerals possess characteristic spectral signatures in the infrared and could similarly be identified from Mars orbit using high resolution remote sensing methods. Clearly, utilization of TES data will be important for optimizing site selection for Exopaleontology, and every effort should be made to benefit from that data before a final decision is made.

  6. Site Selection for Hvdc Ground Electrodes

    NASA Astrophysics Data System (ADS)

    Freire, P. F.; Pereira, S. Y.

    2014-12-01

    High-Voltage Direct Current (HVDC) transmission systems are composed of a bipole transmission line with a converter substation at each end. Each substation may be equipped with a HVDC ground electrode, which is a wide area (up to 1 km Ø) and deep (from 3 to 100m) electrical grounding. When in normal operation, the ground electrode will dissipate in the soil the unbalance of the bipole (~1.5% of the rated current). When in monopolar operation with ground return, the HVDC electrode will inject in the soil the nominal pole continuous current, of about 2000 to 3000 Amperes, continuously for a period up to a few hours. HVDC ground electrodes site selection is a work based on extensive geophysical and geological surveys, in order to attend the desired design requirements established for the electrodes, considering both its operational conditions (maximum soil temperature, working life, local soil voltage gradients etc.) and the interference effects on the installations located up to 50 km away. This poster presents the geophysical investigations conducted primarily for the electrodes site selection, and subsequently for the development of the crust resistivity model, which will be used for the interference studies. A preliminary site selection is conducted, based on general geographical and geological criteria. Subsequently, the geology of each chosen area is surveyed in detail, by means of electromagnetic/electrical geophysical techniques, such as magnetotelluric (deep), TDEM (near-surface) and electroresistivity (shallow). Other complementary geologic and geotechnical surveys are conducted, such as wells drilling (for geotechnical characterization, measurement of the water table depth and water flow, and electromagnetic profiling), and soil and water sampling (for measurement of thermal parameters and evaluation of electrosmosis risk). The site evaluation is a dynamic process along the surveys, and some sites will be discarded. For the two or three final sites, the

  7. Molecular mechanisms of retroviral integration site selection

    PubMed Central

    Kvaratskhelia, Mamuka; Sharma, Amit; Larue, Ross C.; Serrao, Erik; Engelman, Alan

    2014-01-01

    Retroviral replication proceeds through an obligate integrated DNA provirus, making retroviral vectors attractive vehicles for human gene-therapy. Though most of the host cell genome is available for integration, the process of integration site selection is not random. Retroviruses differ in their choice of chromatin-associated features and also prefer particular nucleotide sequences at the point of insertion. Lentiviruses including HIV-1 preferentially integrate within the bodies of active genes, whereas the prototypical gammaretrovirus Moloney murine leukemia virus (MoMLV) favors strong enhancers and active gene promoter regions. Integration is catalyzed by the viral integrase protein, and recent research has demonstrated that HIV-1 and MoMLV targeting preferences are in large part guided by integrase-interacting host factors (LEDGF/p75 for HIV-1 and BET proteins for MoMLV) that tether viral intasomes to chromatin. In each case, the selectivity of epigenetic marks on histones recognized by the protein tether helps to determine the integration distribution. In contrast, nucleotide preferences at integration sites seem to be governed by the ability for the integrase protein to locally bend the DNA duplex for pairwise insertion of the viral DNA ends. We discuss approaches to alter integration site selection that could potentially improve the safety of retroviral vectors in the clinic. PMID:25147212

  8. Feature Selection via Chaotic Antlion Optimization

    PubMed Central

    Zawbaa, Hossam M.; Emary, E.; Grosan, Crina

    2016-01-01

    Background Selecting a subset of relevant properties from a large set of features that describe a dataset is a challenging machine learning task. In biology, for instance, the advances in the available technologies enable the generation of a very large number of biomarkers that describe the data. Choosing the more informative markers along with performing a high-accuracy classification over the data can be a daunting task, particularly if the data are high dimensional. An often adopted approach is to formulate the feature selection problem as a biobjective optimization problem, with the aim of maximizing the performance of the data analysis model (the quality of the data training fitting) while minimizing the number of features used. Results We propose an optimization approach for the feature selection problem that considers a “chaotic” version of the antlion optimizer method, a nature-inspired algorithm that mimics the hunting mechanism of antlions in nature. The balance between exploration of the search space and exploitation of the best solutions is a challenge in multi-objective optimization. The exploration/exploitation rate is controlled by the parameter I that limits the random walk range of the ants/prey. This variable is increased iteratively in a quasi-linear manner to decrease the exploration rate as the optimization progresses. The quasi-linear decrease in the variable I may lead to immature convergence in some cases and trapping in local minima in other cases. The chaotic system proposed here attempts to improve the tradeoff between exploration and exploitation. The methodology is evaluated using different chaotic maps on a number of feature selection datasets. To ensure generality, we used ten biological datasets, but we also used other types of data from various sources. The results are compared with the particle swarm optimizer and with genetic algorithm variants for feature selection using a set of quality metrics. PMID:26963715

  9. Site Selection for the Salt Disposition Facility at the Savannah River Site

    SciTech Connect

    Gladden, J.B.; Rueter, K.J.; Morin, J.P.

    2000-11-15

    A site selection study was conducted to identify a suitable location for the construction and operation of a new Salt Disposition Facility (SDF) at the Savannah River Site (SRS). The facility to be sited is a single processing facility and support buildings that could house either of three technology alternatives being developed by the High Level Waste Systems Engineering Team: Small Tank Tetraphenylborate Precipitation, Crystalline Silicotitanate Non-Elutable Ion Exchange or Caustic Side Solvent Extraction. A fourth alternative, Direct Disposal in grout, is not part of the site selection study because a location has been identified that is unique to this technology (i.e., Z-Area). Facility site selection at SRS is a formal, documented process that seeks to optimize siting of new facilities with respect to facility-specific engineering requirements, sensitive environmental resources, and applicable regulatory requirements. In this manner, the prime objectives of cost minimization, environmental protection, and regulatory compliance are achieved. The results from this geotechnical characterization indicated that continued consideration be given to Site B for the proposed SDF. Suitable topography, the lack of surface hydrology and floodplain issues, no significant groundwater contamination, the presence of minor soft zones along the northeast portion of footprint, and no apparent geological structure in the Gordon Aquitard support this recommendation.

  10. Optimizing Clinical Research Participant Selection with Informatics.

    PubMed

    Weng, Chunhua

    2015-11-01

    Clinical research participants are often not reflective of real-world patients due to overly restrictive eligibility criteria. Meanwhile, unselected participants introduce confounding factors and reduce research efficiency. Biomedical informatics, especially Big Data increasingly made available from electronic health records, offers promising aids to optimize research participant selection through data-driven transparency.

  11. 24 CFR 983.57 - Site selection standards.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false Site selection standards. 983.57... DEVELOPMENT PROJECT-BASED VOUCHER (PBV) PROGRAM Selection of PBV Owner Proposals § 983.57 Site selection standards. (a) Applicability. The site selection requirements in paragraph (d) of this section apply only...

  12. 24 CFR 983.57 - Site selection standards.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 4 2013-04-01 2013-04-01 false Site selection standards. 983.57... DEVELOPMENT PROJECT-BASED VOUCHER (PBV) PROGRAM Selection of PBV Owner Proposals § 983.57 Site selection standards. (a) Applicability. The site selection requirements in paragraph (d) of this section apply only...

  13. 24 CFR 983.57 - Site selection standards.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 4 2012-04-01 2012-04-01 false Site selection standards. 983.57... DEVELOPMENT PROJECT-BASED VOUCHER (PBV) PROGRAM Selection of PBV Owner Proposals § 983.57 Site selection standards. (a) Applicability. The site selection requirements in paragraph (d) of this section apply only...

  14. Active Learning With Optimal Instance Subset Selection.

    PubMed

    Fu, Yifan; Zhu, Xingquan; Elmagarmid, A K

    2013-04-01

    Active learning (AL) traditionally relies on some instance-based utility measures (such as uncertainty) to assess individual instances and label the ones with the maximum values for training. In this paper, we argue that such approaches cannot produce good labeling subsets mainly because instances are evaluated independently without considering their interactions, and individuals with maximal ability do not necessarily form an optimal instance subset for learning. Alternatively, we propose to achieve AL with optimal subset selection (ALOSS), where the key is to find an instance subset with a maximum utility value. To achieve the goal, ALOSS simultaneously considers the following: 1) the importance of individual instances and 2) the disparity between instances, to build an instance-correlation matrix. As a result, AL is transformed to a semidefinite programming problem to select a k-instance subset with a maximum utility value. Experimental results demonstrate that ALOSS outperforms state-of-the-art approaches for AL.

  15. Optimal remediation policy selection under general conditions

    SciTech Connect

    Wang, M.; Zheng, C.

    1997-09-01

    A new simulation-optimization model has been developed for the optimal design of ground-water remediation systems under a variety of field conditions. The model couples genetic algorithm (GA), a global search technique inspired by biological evolution, with MODFLOW and MT3D, two commonly used ground-water flow and solute transport codes. The model allows for multiple management periods in which optimal pumping/injection rates vary with time to reflect the changes in the flow and transport conditions during the remediation process. The objective function of the model incorporates multiple cost terms including the drilling cost, the installation cost, and the costs to extract and treat the contaminated ground water. The simulation-optimization model is first applied to a typical two-dimensional pump-and-treat example with one and three management periods to demonstrate the effectiveness and robustness of the new model. The model is then applied to a large-scale three-dimensional field problem to determine the minimum pumping needed to contain an existing contaminant plume. The optimal solution as determined in this study is compared with a previous solution based on trial-and-error selection.

  16. Optimal Sensor Selection for Health Monitoring Systems

    NASA Technical Reports Server (NTRS)

    Santi, L. Michael; Sowers, T. Shane; Aguilar, Robert B.

    2005-01-01

    Sensor data are the basis for performance and health assessment of most complex systems. Careful selection and implementation of sensors is critical to enable high fidelity system health assessment. A model-based procedure that systematically selects an optimal sensor suite for overall health assessment of a designated host system is described. This procedure, termed the Systematic Sensor Selection Strategy (S4), was developed at NASA John H. Glenn Research Center in order to enhance design phase planning and preparations for in-space propulsion health management systems (HMS). Information and capabilities required to utilize the S4 approach in support of design phase development of robust health diagnostics are outlined. A merit metric that quantifies diagnostic performance and overall risk reduction potential of individual sensor suites is introduced. The conceptual foundation for this merit metric is presented and the algorithmic organization of the S4 optimization process is described. Representative results from S4 analyses of a boost stage rocket engine previously under development as part of NASA's Next Generation Launch Technology (NGLT) program are presented.

  17. Selected Isotopes for Optimized Fuel Assembly Tags

    SciTech Connect

    Gerlach, David C.; Mitchell, Mark R.; Reid, Bruce D.; Gesh, Christopher J.; Hurley, David E.

    2008-10-01

    In support of our ongoing signatures project we present information on 3 isotopes selected for possible application in optimized tags that could be applied to fuel assemblies to provide an objective measure of burnup. 1. Important factors for an optimized tag are compatibility with the reactor environment (corrosion resistance), low radioactive activation, at least 2 stable isotopes, moderate neutron absorption cross-section, which gives significant changes in isotope ratios over typical fuel assembly irradiation levels, and ease of measurement in the SIMS machine 2. From the candidate isotopes presented in the 3rd FY 08 Quarterly Report, the most promising appear to be Titanium, Hafnium, and Platinum. The other candidate isotopes (Iron, Tungsten, exhibited inadequate corrosion resistance and/or had neutron capture cross-sections either too high or too low for the burnup range of interest.

  18. Protein pharmacophore selection using hydration-site analysis

    PubMed Central

    Hu, Bingjie; Lill, Markus A.

    2012-01-01

    Virtual screening using pharmacophore models is an efficient method to identify potential lead compounds for target proteins. Pharmacophore models based on protein structures are advantageous because a priori knowledge of active ligands is not required and the models are not biased by the chemical space of previously identified actives. However, in order to capture most potential interactions between all potentially binding ligands and the protein, the size of the pharmacophore model, i.e. number of pharmacophore elements, is typically quite large and therefore reduces the efficiency of pharmacophore based screening. We have developed a new method to select important pharmacophore elements using hydration-site information. The basic premise is that ligand functional groups that replace water molecules in the apo protein contribute strongly to the overall binding affinity of the ligand, due to the additional free energy gained from releasing the water molecule into the bulk solvent. We computed the free energy of water released from the binding site for each hydration site using thermodynamic analysis of molecular dynamics (MD) simulations. Pharmacophores which are co-localized with hydration sites with estimated favorable contributions to the free energy of binding are selected to generate a reduced pharmacophore model. We constructed reduced pharmacophore models for three protein systems and demonstrated good enrichment quality combined with high efficiency. The reduction in pharmacophore model size reduces the required screening time by a factor of 200–500 compared to using all protein pharmacophore elements. We also describe a training process using a small set of known actives to reliably select the optimal set of criteria for pharmacophore selection for each protein system. PMID:22397751

  19. Spatially-Correlated Risk in Nature Reserve Site Selection

    PubMed Central

    Albers, Heidi J.; Busby, Gwenlyn M.; Hamaide, Bertrand; Ando, Amy W.; Polasky, Stephen

    2016-01-01

    Establishing nature reserves protects species from land cover conversion and the resulting loss of habitat. Even within a reserve, however, many factors such as fires and defoliating insects still threaten habitat and the survival of species. To address the risk to species survival after reserve establishment, reserve networks can be created that allow some redundancy of species coverage to maximize the expected number of species that survive in the presence of threats. In some regions, however, the threats to species within a reserve may be spatially correlated. As examples, fires, diseases, and pest infestations can spread from a starting point and threaten neighboring parcels’ habitats, in addition to damage caused at the initial location. This paper develops a reserve site selection optimization framework that compares the optimal reserve networks in cases where risks do and do not reflect spatial correlation. By exploring the impact of spatially-correlated risk on reserve networks on a stylized landscape and on an Oregon landscape, this analysis demonstrates an appropriate and feasible method for incorporating such post-reserve establishment risks in the reserve site selection literature as an additional tool to be further developed for future conservation planning. PMID:26789127

  20. Spatially-Correlated Risk in Nature Reserve Site Selection.

    PubMed

    Albers, Heidi J; Busby, Gwenlyn M; Hamaide, Bertrand; Ando, Amy W; Polasky, Stephen

    2016-01-01

    Establishing nature reserves protects species from land cover conversion and the resulting loss of habitat. Even within a reserve, however, many factors such as fires and defoliating insects still threaten habitat and the survival of species. To address the risk to species survival after reserve establishment, reserve networks can be created that allow some redundancy of species coverage to maximize the expected number of species that survive in the presence of threats. In some regions, however, the threats to species within a reserve may be spatially correlated. As examples, fires, diseases, and pest infestations can spread from a starting point and threaten neighboring parcels' habitats, in addition to damage caused at the initial location. This paper develops a reserve site selection optimization framework that compares the optimal reserve networks in cases where risks do and do not reflect spatial correlation. By exploring the impact of spatially-correlated risk on reserve networks on a stylized landscape and on an Oregon landscape, this analysis demonstrates an appropriate and feasible method for incorporating such post-reserve establishment risks in the reserve site selection literature as an additional tool to be further developed for future conservation planning.

  1. Early Site Permit Demonstration Program: Siting Guide, Site selection and evaluation criteria for an early site permit application. Revision 1

    SciTech Connect

    Not Available

    1993-03-24

    In August 1991, the Joint Contractors came to agreement with Sandia National Laboratories (SNL) and the Department of Energy (DOE) on a workscope for the cost-shared Early Site Permit Demonstration Program. One task within the scope was the development of a guide for site selection criteria and procedures. A generic Siting Guide his been prepared that is a roadmap and tool for applicants to use developing detailed siting plans for their specific region of the country. The guide presents three fundamental principles that, if used, ensure a high degree of success for an ESP applicant. First, the site selection process should take into consideration environmentally diverse site locations within a given region of interest. Second, the process should contain appropriate opportunities for input from the public. Third, the process should be applied so that it is clearly reasonable to an impartial observer, based on appropriately selected criteria, including criteria which demonstrate that the site can host an advanced light water reactor (ALWR). The Siting Guide provides for a systematic, comprehensive site selection process in which three basic types of criteria (exclusionary, avoidance, and suitability) are presented via a four-step procedure. It provides a check list of the criteria for each one of these steps. Criteria are applied qualitatively, as well as presented numerically, within the guide. The applicant should use the generic guide as an exhaustive checklist, customizing the guide to his individual situation.

  2. Selectively-informed particle swarm optimization

    PubMed Central

    Gao, Yang; Du, Wenbo; Yan, Gang

    2015-01-01

    Particle swarm optimization (PSO) is a nature-inspired algorithm that has shown outstanding performance in solving many realistic problems. In the original PSO and most of its variants all particles are treated equally, overlooking the impact of structural heterogeneity on individual behavior. Here we employ complex networks to represent the population structure of swarms and propose a selectively-informed PSO (SIPSO), in which the particles choose different learning strategies based on their connections: a densely-connected hub particle gets full information from all of its neighbors while a non-hub particle with few connections can only follow a single yet best-performed neighbor. Extensive numerical experiments on widely-used benchmark functions show that our SIPSO algorithm remarkably outperforms the PSO and its existing variants in success rate, solution quality, and convergence speed. We also explore the evolution process from a microscopic point of view, leading to the discovery of different roles that the particles play in optimization. The hub particles guide the optimization process towards correct directions while the non-hub particles maintain the necessary population diversity, resulting in the optimum overall performance of SIPSO. These findings deepen our understanding of swarm intelligence and may shed light on the underlying mechanism of information exchange in natural swarm and flocking behaviors. PMID:25787315

  3. Optimizing Restriction Site Placement for Synthetic Genomes

    NASA Astrophysics Data System (ADS)

    Montes, Pablo; Memelli, Heraldo; Ward, Charles; Kim, Joondong; Mitchell, Joseph S. B.; Skiena, Steven

    Restriction enzymes are the workhorses of molecular biology. We introduce a new problem that arises in the course of our project to design virus variants to serve as potential vaccines: we wish to modify virus-length genomes to introduce large numbers of unique restriction enzyme recognition sites while preserving wild-type function by substitution of synonymous codons. We show that the resulting problem is NP-Complete, give an exponential-time algorithm, and propose effective heuristics, which we show give excellent results for five sample viral genomes. Our resulting modified genomes have several times more unique restriction sites and reduce the maximum gap between adjacent sites by three to nine-fold.

  4. Selecting the Right Site: 10 Considerations to Chart the Future

    ERIC Educational Resources Information Center

    Boehlke, Mark S.

    2013-01-01

    When considering a new school construction project, the site selection and evaluation process is a critical step in early planning. Selecting the right site is paramount to the project and can have a major impact on the outcome of a referendum. Careful consideration and thoughtful attention to site-related issues and details can set the course not…

  5. Investigation of a novel approach for aquaculture site selection.

    PubMed

    Falconer, Lynne; Telfer, Trevor C; Ross, Lindsay G

    2016-10-01

    This study investigated the potential use of two "species distribution models" (SDMs), Mahalanobis Typicality and Maxent, for aquaculture site selection. SDMs are used in ecological studies to predict the spatial distribution of species based on analysis of conditions at locations of known presence or absence. Here the input points are aquaculture sites, rather than species occurrence, thus the models evaluate the parameters at the sites and identify similar areas across the rest of the study area. This is a novel approach that avoids the need for data reclassification and weighting which can be a source of conflict and uncertainty within the commonly used multi-criteria evaluation (MCE) technique. Using pangasius culture in the Mekong Delta, Vietnam, as a case study, Mahalanobis Typicality and Maxent SDMs were evaluated against two models developed using the MCE approach. Mahalanobis Typicality and Maxent assess suitability based on similarity to existing farms, while the MCE approach assesses suitability using optimal values for culture. Mahalanobis Typicality considers the variables to have equal importance whereas Maxent analyses the variables to determine those which influence the distribution of the input data. All of the models indicate there are suitable areas for culture along the two main channels of the Mekong River which are currently used to farm pangasius and also inland in the north and east of the study area. The results show the Mahalanobis Typicality model had more high scoring areas and greater overall similarity than Maxent to the MCE outputs, suggesting, for this case study, it was the most appropriate SDM for aquaculture site selection. With suitable input data, a combined SDM and MCE model would overcome limitations of the individual approaches, allowing more robust planning and management decisions for aquaculture, other stakeholders and the environment.

  6. Optimal test selection for prediction uncertainty reduction

    DOE PAGES

    Mullins, Joshua; Mahadevan, Sankaran; Urbina, Angel

    2016-12-02

    Economic factors and experimental limitations often lead to sparse and/or imprecise data used for the calibration and validation of computational models. This paper addresses resource allocation for calibration and validation experiments, in order to maximize their effectiveness within given resource constraints. When observation data are used for model calibration, the quality of the inferred parameter descriptions is directly affected by the quality and quantity of the data. This paper characterizes parameter uncertainty within a probabilistic framework, which enables the uncertainty to be systematically reduced with additional data. The validation assessment is also uncertain in the presence of sparse and imprecisemore » data; therefore, this paper proposes an approach for quantifying the resulting validation uncertainty. Since calibration and validation uncertainty affect the prediction of interest, the proposed framework explores the decision of cost versus importance of data in terms of the impact on the prediction uncertainty. Often, calibration and validation tests may be performed for different input scenarios, and this paper shows how the calibration and validation results from different conditions may be integrated into the prediction. Then, a constrained discrete optimization formulation that selects the number of tests of each type (calibration or validation at given input conditions) is proposed. Furthermore, the proposed test selection methodology is demonstrated on a microelectromechanical system (MEMS) example.« less

  7. Optimal test selection for prediction uncertainty reduction

    SciTech Connect

    Mullins, Joshua; Mahadevan, Sankaran; Urbina, Angel

    2016-12-02

    Economic factors and experimental limitations often lead to sparse and/or imprecise data used for the calibration and validation of computational models. This paper addresses resource allocation for calibration and validation experiments, in order to maximize their effectiveness within given resource constraints. When observation data are used for model calibration, the quality of the inferred parameter descriptions is directly affected by the quality and quantity of the data. This paper characterizes parameter uncertainty within a probabilistic framework, which enables the uncertainty to be systematically reduced with additional data. The validation assessment is also uncertain in the presence of sparse and imprecise data; therefore, this paper proposes an approach for quantifying the resulting validation uncertainty. Since calibration and validation uncertainty affect the prediction of interest, the proposed framework explores the decision of cost versus importance of data in terms of the impact on the prediction uncertainty. Often, calibration and validation tests may be performed for different input scenarios, and this paper shows how the calibration and validation results from different conditions may be integrated into the prediction. Then, a constrained discrete optimization formulation that selects the number of tests of each type (calibration or validation at given input conditions) is proposed. Furthermore, the proposed test selection methodology is demonstrated on a microelectromechanical system (MEMS) example.

  8. Factors concerned with sanitary landfill site selection: General discussion

    NASA Technical Reports Server (NTRS)

    Graff, W. J.; Stone, L. J.

    1972-01-01

    A general view of factors affecting site selection for sanitary landfill sites is presented. Examinations were made of operational methods, possible environment pollution, types of waste to be disposed, base and cover materials, and the economics involved in the operation.

  9. Radioactive waste repository site selection in the Republic of Slovenia

    SciTech Connect

    Jeran, M.; Duhovnik, B.

    1993-12-31

    The report shows the procedure for the low and intermediate level radwaste (LLW and ILW) repository site selection and the work performed up to the present. The procedure for the repository site selection is divided into four steps. In the first step the unsuitable areas are excluded by taking into consideration the rough exclusion criteria. In the second step, the remaining suitable areas are screened to identify the potential sites with respect to preference criteria. In the third step three to five candidate sites were assessed and selected among the potential sites. In the final, the fourth step, detailed site investigation and confirmation of one or two most suitable sites will follow. In Slovenia the 1st, the 2nd and the 3rd step of site selection have been completed, while step 4 is now in progress.

  10. Brownfields Technology Primer: Selecting and Using Phytoremediation for Site Cleanup

    EPA Pesticide Factsheets

    This primer explains the phytoremediation process, discusses the potential advantages and considerations in selecting phytoremediation to clean up brownfields sites, and provides information on additional resources about phytoremediation.

  11. A Site Selection Technique for Martian Habitats

    NASA Astrophysics Data System (ADS)

    Kerr, Mark E.

    2004-02-01

    The human exploration of Mars will require the identification of a region that includes the largest number of beneficial sites and properties. Because of the numerous relevant parameters and the complexity of the Martian surface an automated technique was tested using Ian L. McHarg's (1969) sieve mapping method. Beginning with a global inventory of features areas of interest were determined by astrobiology, geology and other mission parameters, with the goal of finding a series of possible habitat sites to support a traverse mission through Utopia Planitia, Isidis, and Elysium Planitia. We identified important occurrences of hydrogen isotopes, centers of past volcanic activity, significant impact craters and possible evidence of past and present water and superimposed these locations to determine the best site for the habitat, which is situated between the Elysium volcanoes, Isidis, Gale Crater.

  12. THE SCHOOL SITE--ITS SELECTION, ANALYSIS, DEVELOPMENT AND MAINTENANCE.

    ERIC Educational Resources Information Center

    BRUNING, WALTER F.

    SCHOOL ADMINISTRATORS AND COMMUNITY PLANNERS CAN AID THE SCHOOL SITE SELECTION PROCESS BY WORKING TOGETHER ON A COMMUNITY MASTER PLAN. MANY COMMUNITIES HAVE DEVELOPED SUCH A PLAN UNDER THE STATE AND FEDERALLY AIDED 701 PROGRAM. SOUND SITE SELECTION PRINCIPLES REQUIRE CONSIDERATION OF OTHER FACTORS THAN STUDENT POPULATION DISTRIBUTION. IDEALLY…

  13. Nest-site selection in the acorn woodpecker

    USGS Publications Warehouse

    Hooge, P.N.; Stanback, M.T.; Koenig, Walter D.

    1999-01-01

    Acorn Woodpeckers (Melanerpes formicivorus) at Hastings Reservation in central California prefer to nest in dead limbs in large, dead valley oaks (Quercus lobata) and California sycamores (Platanus racemosa) that are also frequently used as acorn storage trees. Based on 232 nest cavities used over an 18-year period, we tested whether preferred or modal nest-site characters were associated with increased reproductive success (the 'nest-site quality' hypothesis). We also examined whether more successful nests were likely to experience more favorable microclimatic conditions or to be less accessible to terrestrial predators. We found only equivocal support for the nest-site quality hypothesis: only 1 of 5 preferred characters and 2 of 10 characters exhibiting a clear modality were correlated with higher reproductive success. All three characteristics of nests known or likely to be associated with a more favorable microclimate, and two of five characteristics likely to render nests less accessible to predators, were correlated with higher reproductive success: These results suggest that nest cavities in this population are built in part to take advantage of favorable microclimatic conditions and, to a lesser extent, to reduce access to predators. However, despite benefits of particular nest characteristics, birds frequently nested in apparently suboptimal cavities. We also found a significant relationship between mean group size and the history of occupancy of particular territories and the probability of nest cavities being built in microclimatically favorable live limbs, suggesting that larger groups residing on more stable territories were better able to construct nests with optimal characteristics. This indicates that there may be demographic, as well as ecological, constraints on nest-site selection in this primary cavity nester.

  14. Lunar Observer Laser Altimeter observations for lunar base site selection

    NASA Technical Reports Server (NTRS)

    Garvin, James B.; Bufton, Jack L.

    1992-01-01

    One of the critical datasets for optimal selection of future lunar landing sites is local- to regional-scale topography. Lunar base site selection will require such data for both engineering and scientific operations purposes. The Lunar Geoscience Orbiter or Lunar Observer is the ideal precursory science mission from which to obtain this required information. We suggest that a simple laser altimeter instrument could be employed to measure local-scale slopes, heights, and depths of lunar surface features important to lunar base planning and design. For this reason, we have designed and are currently constructing a breadboard of a Lunar Observer Laser Altimeter (LOLA) instrument capable of acquiring contiguous-footprint topographic profiles with both 30-m and 300-m along-track resolution. This instrument meets all the severe weight, power, size, and data rate limitations imposed by Observer-class spacecraft. In addition, LOLA would be capable of measuring the within-footprint vertical roughness of the lunar surface, and the 1.06-micron relative surface reflectivity at normal incidence. We have used airborne laser altimeter data for a few representative lunar analog landforms to simulate and analyze LOLA performance in a 100-km lunar orbit. We demonstrate that this system in its highest resolution mode (30-m diameter footprints) would quantify the topography of all but the very smallest lunar landforms. At its global mapping resolution (300-m diameter footprints), LOLA would establish the topographic context for lunar landing site selection by providing the basis for constructing a 1-2 km spatial resolution global, geodetic topographic grid that would contain a high density of observations (e.g., approximately 1000 observations per each 1 deg by 1 deg cell at the lunar equator). The high spatial and vertical resolution measurements made with a LOLA-class instrument on a precursory Lunar Observer would be highly synergistic with high-resolution imaging datasets, and

  15. An Evaluation Guide for Selecting a Junior College Site.

    ERIC Educational Resources Information Center

    Reida, G. W.

    Emphasis is placed upon conceiving the site as an integral part of the total educational environment. Preliminary steps are suggested for planning a junior college campus, placing emphasis upon the need for a master plan. Criteria for site selection are discussed for site size, student enrollment, land use patterns, and accessibility. Directions…

  16. 15 CFR 921.12 - Post site selection.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... NOAA approval of a proposed site, the state may submit a request for funds to develop the draft... and biological characteristics of the site approved by NOAA necessary for providing EIS information to NOAA. The state's request for these post site selection funds must be accompanied by the...

  17. 15 CFR 921.12 - Post site selection.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... NOAA approval of a proposed site, the state may submit a request for funds to develop the draft... and biological characteristics of the site approved by NOAA necessary for providing EIS information to NOAA. The state's request for these post site selection funds must be accompanied by the...

  18. 15 CFR 921.12 - Post site selection.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... NOAA approval of a proposed site, the state may submit a request for funds to develop the draft... and biological characteristics of the site approved by NOAA necessary for providing EIS information to NOAA. The state's request for these post site selection funds must be accompanied by the...

  19. 15 CFR 921.12 - Post site selection.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... NOAA approval of a proposed site, the state may submit a request for funds to develop the draft... and biological characteristics of the site approved by NOAA necessary for providing EIS information to NOAA. The state's request for these post site selection funds must be accompanied by the...

  20. 15 CFR 921.12 - Post site selection.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... NOAA approval of a proposed site, the state may submit a request for funds to develop the draft... and biological characteristics of the site approved by NOAA necessary for providing EIS information to NOAA. The state's request for these post site selection funds must be accompanied by the...

  1. Site selection and licensing issues: Southwest Compact low-level radioactive waste disposal site

    SciTech Connect

    Grant, J.L.

    1989-11-01

    The low-level radioactive waste disposal site in California is being selected through a three-phase program. Phase 1 is a systematic statewide, regional, and local screening study. This program was conducted during 1986 and 1987, and culminated in the selection of three candidate sites fur further study. The candidate sites are identified as the Panamint, Silurian, and Ward Valley sites. Phase 2 comprises site characterization and environmental and socio-economic impact study activities at the three candidate sites. Based upon the site characterization studies, the candidate sites are ranked according to the desirability and conformance with regulatory requirements. Phase 3 comprises preparation of a license application for the selected candidate site. The license application will include a detailed characterization of the site, detailed design and operations plans for the proposed facility, and assessments of potential impacts of the site upon the environment and the local communities. Five types of siting criteria were developed to govern the site selection process. These types are: technical suitability exclusionary criteria, high-avoidance criteria beyond technical suitability requirements, discretionary criteria, public acceptance, and schedule requirements of the LLWR Policy Act Amendments. This paper discusses the application of the hydrological and geotechnical criteria during the siting and licensing studies in California. These criteria address site location and performance, and the degree to which present and future site behavior can be predicted. Primary regulatory requirements governing the suitability of a site are that the site must be hydrologically and geologically simple enough for the confident prediction of future behavior, and that the site must be stable enough that frequent or intensive maintenance of the closed site will not be required. This paper addresses the methods to measure site suitability at each stage of the process, methods to

  2. Scour at selected bridge sites in Mississippi

    USGS Publications Warehouse

    Wilson, K.V.

    1995-01-01

    Scour data were collected during 1936-94 at 22 bridge sites in Mississippi. The drainage area of the bridge-scour sites ranged from 60.8 to 5,720 square miles, and the slope in the vicinity of each site ranged from 0.00011 to 0.00163 foot per foot. Measured pier-scour depths ranged from 0.6 to 20.4 feet. Measured total-scour depths at minimum-bed elevation ranged from 5.2 to 29.8 feet. Recurrence intervals of measured streamflow discharges ranged from less than 2 years to about 500 years. All of the Mississippi pier-scour depths were within 2.3 times the normal pier width, which agreed with previous research. Only 12 (6 percent) of the 190 measured pier-scour depths were greater than 1.1 times the normal pier width. Measured pier-scour depths were as much as 2.24 times a normal pier width of 3.3 feet. However, for pier widths greater than about 4 feet, measured pier-scour depths were significantly less than 2.3 times the normal pier width. An envelope-curve equation for the Mississippi pier-scour data was developed by relating pier-scour depth divided by normal pier width to measured approach-flow depth divided by normal pier width. The envelope-curve equation predictions could be used for reasonable verifi- cations of the HEC-18 pier-scour predictions, currently required for the design and mainte- nance of bridges over waterways in Mississippi.

  3. Selection of promising sites for magma energy experiments

    SciTech Connect

    Carson, C.C.

    1985-01-01

    The Long Valley and Coso Hot Springs areas of California have been identified as the most promising sites for conducting a magma energy extraction experiment. These two locations were selected from among the potential sites on the basis of several factors that are critical to the success of the proposed long-term energy extraction experiment. These factors include the likelihood of the existence of shallow magma targets as well as several other drilling, energy extraction and programmatic considerations. As the magma energy extraction program continues, these sites will be analyzed in detail so that one can be selected as the site for the planned magma experiment.

  4. History of the production complex: The methods of site selection

    SciTech Connect

    Not Available

    1987-09-01

    Experience taught the Atomic Energy Commission how to select the best possible sites for its production facilities. AEC officials learned from the precedents set by the wartime Manhattan Project and from their own mistakes in the immediate postwar years. This volume discusses several site selections. The sites covered are: (1) the Hanford Reservation, (2) the Idaho reactor site, (3) the Savannah River Plant, (4) the Paducah Gaseous Diffusion Plant, (5) the Portsmouth Gaseous Diffusion Plant, (6) the Fernald Production Center, (7) the PANTEX and Spoon River Plants, (8) the Rocky Flats Fabrication Facility, and (9) the Miamisburg and Pinellas plants. (JDH)

  5. Preliminary site selection report for the new sanitary landfill at the Savannah River Site

    SciTech Connect

    Not Available

    1992-12-01

    The Savannah River Site (SRS) has proposed a new sanitary landfill (NSL) for solid waste. A site selection team, comprised of representatives from Westinghouse Savannah River Company (WSRC) evaluated potential landfill sites. The site selection team conducted an initial screening of SRS to eliminate unsuitable areas. The screening was based on criteria that were principally environmental factors; however, the criteria also included avoiding areas with unacceptable features for construction or operation of the facility. This initial screening identified seven candidate sites for further evaluation.

  6. Optimal smoothing of site-energy distributions from adsorption isotherms

    SciTech Connect

    Brown, L.F.; Travis, B.J.

    1983-01-01

    The equation for the adsorption isotherm on a heterogeneous surface is a Fredholm integral equation. In solving it for the site-energy distribution (SED), some sort of smoothing must be carried out. The optimal amount of smoothing will give the most information that is possible without introducing nonexistent structure into the SED. Recently, Butler, Reeds, and Dawson proposed a criterion (the BRD criterion) for choosing the optimal smoothing parameter when using regularization to solve Fredholm equations. The BRD criterion is tested for its suitability in obtaining optimal SED's. This criterion is found to be too conservative. While using it never introduces nonexistent structure into the SED, significant information is often lost. At present, no simple criterion for choosing the optimal smoothing parameter exists, and a modeling approach is recommended.

  7. 40 CFR 228.6 - Specific criteria for site selection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Specific criteria for site selection. 228.6 Section 228.6 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE MANAGEMENT OF DISPOSAL SITES FOR OCEAN DUMPING § 228.6 Specific criteria for...

  8. The economic and social aspects of sanitary landfill site selection

    NASA Technical Reports Server (NTRS)

    Graff, W. J.; Rogers, J. R.

    1972-01-01

    The factors involved in the selection of suitable sites for sanitary land fills are discussed. The economic considerations and problems of social acceptance are considered the most important. The subjects discussed are: (1) accessibility of land, (2) availability of cover material, (3) expected capacity of site, (4) cover material and compaction, (5) fire protection, (6) site location with respect to residential and industrial areas, and (7) land usage after landfill completion.

  9. Applications of Optimal Building Energy System Selection and Operation

    SciTech Connect

    Marnay, Chris; Stadler, Michael; Siddiqui, Afzal; DeForest, Nicholas; Donadee, Jon; Bhattacharya, Prajesh; Lai, Judy

    2011-04-01

    Berkeley Lab has been developing the Distributed Energy Resources Customer Adoption Model (DER-CAM) for several years. Given load curves for energy services requirements in a building microgrid (u grid), fuel costs and other economic inputs, and a menu of available technologies, DER-CAM finds the optimum equipment fleet and its optimum operating schedule using a mixed integer linear programming approach. This capability is being applied using a software as a service (SaaS) model. Optimisation problems are set up on a Berkeley Lab server and clients can execute their jobs as needed, typically daily. The evolution of this approach is demonstrated by description of three ongoing projects. The first is a public access web site focused on solar photovoltaic generation and battery viability at large commercial and industrial customer sites. The second is a building CO2 emissions reduction operations problem for a University of California, Davis student dining hall for which potential investments are also considered. And the third, is both a battery selection problem and a rolling operating schedule problem for a large County Jail. Together these examples show that optimization of building u grid design and operation can be effectively achieved using SaaS.

  10. Hypermutable Non-Synonymous Sites Are under Stronger Negative Selection

    PubMed Central

    Kondrashov, Fyodor A.; Adzuhbei, Ivan A.; Kondrashov, Alexey S.; Sunyaev, Shamil

    2008-01-01

    Mutation rate varies greatly between nucleotide sites of the human genome and depends both on the global genomic location and the local sequence context of a site. In particular, CpG context elevates the mutation rate by an order of magnitude. Mutations also vary widely in their effect on the molecular function, phenotype, and fitness. Independence of the probability of occurrence of a new mutation's effect has been a fundamental premise in genetics. However, highly mutable contexts may be preserved by negative selection at important sites but destroyed by mutation at sites under no selection. Thus, there may be a positive correlation between the rate of mutations at a nucleotide site and the magnitude of their effect on fitness. We studied the impact of CpG context on the rate of human–chimpanzee divergence and on intrahuman nucleotide diversity at non-synonymous coding sites. We compared nucleotides that occupy identical positions within codons of identical amino acids and only differ by being within versus outside CpG context. Nucleotides within CpG context are under a stronger negative selection, as revealed by their lower, proportionally to the mutation rate, rate of evolution and nucleotide diversity. In particular, the probability of fixation of a non-synonymous transition at a CpG site is two times lower than at a CpG site. Thus, sites with different mutation rates are not necessarily selectively equivalent. This suggests that the mutation rate may complement sequence conservation as a characteristic predictive of functional importance of nucleotide sites. PMID:19043566

  11. Optimization of a crossing system using mate selection

    PubMed Central

    Li, Yongjun; Werf, Julius HJ van der; Kinghorn, Brian P

    2006-01-01

    A simple model based on one single identified quantitative trait locus (QTL) in a two-way crossing system was used to demonstrate the power of mate selection algorithms as a natural means of opportunistic line development for optimization of crossbreeding programs over multiple generations. Mate selection automatically invokes divergent selection in two parental lines for an over-dominant QTL and increased frequency of the favorable allele toward fixation in the sire-line for a fully-dominant QTL. It was concluded that an optimal strategy of line development could be found by mate selection algorithms for a given set of parameters such as genetic model of QTL, breeding objective and initial frequency of the favorable allele in the base populations, etc. The same framework could be used in other scenarios, such as programs involving crossing to exploit breed effects and heterosis. In contrast to classical index selection, this approach to mate selection can optimize long-term responses. PMID:16492372

  12. Optimization of a crossing system using mate selection.

    PubMed

    Li, Yongjun; van der Werf, Julius H J; Kinghorn, Brian P

    2006-01-01

    A simple model based on one single identified quantitative trait locus (QTL) in a two-way crossing system was used to demonstrate the power of mate selection algorithms as a natural means of opportunistic line development for optimization of crossbreeding programs over multiple generations. Mate selection automatically invokes divergent selection in two parental lines for an over-dominant QTL and increased frequency of the favorable allele toward fixation in the sire-line for a fully-dominant QTL. It was concluded that an optimal strategy of line development could be found by mate selection algorithms for a given set of parameters such as genetic model of QTL, breeding objective and initial frequency of the favorable allele in the base populations, etc. The same framework could be used in other scenarios, such as programs involving crossing to exploit breed effects and heterosis. In contrast to classical index selection, this approach to mate selection can optimize long-term responses.

  13. Geospatial Optimization of Siting Large-Scale Solar Projects

    SciTech Connect

    Macknick, J.; Quinby, T.; Caulfield, E.; Gerritsen, M.; Diffendorfer, J.; Haines, S.

    2014-03-01

    Recent policy and economic conditions have encouraged a renewed interest in developing large-scale solar projects in the U.S. Southwest. However, siting large-scale solar projects is complex. In addition to the quality of the solar resource, solar developers must take into consideration many environmental, social, and economic factors when evaluating a potential site. This report describes a proof-of-concept, Web-based Geographical Information Systems (GIS) tool that evaluates multiple user-defined criteria in an optimization algorithm to inform discussions and decisions regarding the locations of utility-scale solar projects. Existing siting recommendations for large-scale solar projects from governmental and non-governmental organizations are not consistent with each other, are often not transparent in methods, and do not take into consideration the differing priorities of stakeholders. The siting assistance GIS tool we have developed improves upon the existing siting guidelines by being user-driven, transparent, interactive, capable of incorporating multiple criteria, and flexible. This work provides the foundation for a dynamic siting assistance tool that can greatly facilitate siting decisions among multiple stakeholders.

  14. On Optimal Input Design and Model Selection for Communication Channels

    SciTech Connect

    Li, Yanyan; Djouadi, Seddik M; Olama, Mohammed M

    2013-01-01

    In this paper, the optimal model (structure) selection and input design which minimize the worst case identification error for communication systems are provided. The problem is formulated using metric complexity theory in a Hilbert space setting. It is pointed out that model selection and input design can be handled independently. Kolmogorov n-width is used to characterize the representation error introduced by model selection, while Gel fand and Time n-widths are used to represent the inherent error introduced by input design. After the model is selected, an optimal input which minimizes the worst case identification error is shown to exist. In particular, it is proven that the optimal model for reducing the representation error is a Finite Impulse Response (FIR) model, and the optimal input is an impulse at the start of the observation interval. FIR models are widely popular in communication systems, such as, in Orthogonal Frequency Division Multiplexing (OFDM) systems.

  15. Site Selection for Surplus Plutonium Disposition Facilities at the Savannah River Site

    SciTech Connect

    Wike, L.D.

    2000-08-17

    A site selection study was conducted to evaluate locations for the proposed Surplus Plutonium Disposition Facilities. Facilities to be located include the Mixed Oxide (MOX) Fuel Fabrication Facility, the Pit Disassembly and Conversion Facility (PDCF), and the Plutonium Immobilization Project (PIP) facility. Objectives of the study include: (1) Confirm that the Department of Energy (DOE) selected locations for the MOX and PDCF were suitable based on selected siting criteria, (2) Recommend a site in the vicinity of F Area that is suitable for the PIP, and (3) Identify alternative suitable sites for one or more of these facilities in the event that further geotechnical characterization or other considerations result in disqualification of a currently proposed site.

  16. Optimized tuner selection for engine performance estimation

    NASA Technical Reports Server (NTRS)

    Simon, Donald L. (Inventor); Garg, Sanjay (Inventor)

    2013-01-01

    A methodology for minimizing the error in on-line Kalman filter-based aircraft engine performance estimation applications is presented. This technique specifically addresses the underdetermined estimation problem, where there are more unknown parameters than available sensor measurements. A systematic approach is applied to produce a model tuning parameter vector of appropriate dimension to enable estimation by a Kalman filter, while minimizing the estimation error in the parameters of interest. Tuning parameter selection is performed using a multi-variable iterative search routine which seeks to minimize the theoretical mean-squared estimation error. Theoretical Kalman filter estimation error bias and variance values are derived at steady-state operating conditions, and the tuner selection routine is applied to minimize these values. The new methodology yields an improvement in on-line engine performance estimation accuracy.

  17. Optimization of a Dibenzodiazepine Hit to a Potent and Selective Allosteric PAK1 Inhibitor

    PubMed Central

    2015-01-01

    The discovery of inhibitors targeting novel allosteric kinase sites is very challenging. Such compounds, however, once identified could offer exquisite levels of selectivity across the kinome. Herein we report our structure-based optimization strategy of a dibenzodiazepine hit 1, discovered in a fragment-based screen, yielding highly potent and selective inhibitors of PAK1 such as 2 and 3. Compound 2 was cocrystallized with PAK1 to confirm binding to an allosteric site and to reveal novel key interactions. Compound 3 modulated PAK1 at the cellular level and due to its selectivity enabled valuable research to interrogate biological functions of the PAK1 kinase. PMID:26191365

  18. Unusual sleeping site selection by southern bamboo lemurs.

    PubMed

    Eppley, Timothy M; Donati, Giuseppe; Ganzhorn, Jörg U

    2016-04-01

    Selection of sleeping sites has consequences for individual fitness. Non-human primates often bias their selection towards arboreal sites, and the lemurs of Madagascar typically rest/sleep in trees, tree holes, and/or constructed nests. Three non-mutually exclusive hypotheses to explain sleeping site selection include protection from predators, avoidance of parasitic vectors, and improved thermoregulation. Here, we examine these hypotheses for the unusual sleeping site selections by the southern bamboo lemur (Hapalemur meridionalis). Within the Mandena littoral forest of southeast Madagascar, the southern bamboo lemur is known for its ecological flexibility compared to other bamboo lemur species, including a dietary niche expansion to feeding on the ground. Between October 2012 and December 2013, we observed bamboo lemurs from three social groups for 1778.67 h, conducting full-day focal follows on 11 adult individuals (five males, six females). During this period, all three groups were observed to sleep on the ground, with one of these groups also using an abandoned nest of a Madagascar crested ibis (Lophotibis cristata). We collected habitat and temperature data to examine whether selection was influenced by environmental variables. Terrestrial sleeping (N = 17) was observed in all individuals but one adult female, with individuals burrowing under thick vegetation more often during the hot austral summer. While difficult to rigorously test, it is possible that terrestrial sleep sites and/or sleeping in a bird nest may impair visual detection by some aerial and terrestrial predators. Neither of these sites (i.e., terrestrial sleeping or use of a bird nest), however, is likely to minimize exposure to parasites/vectors. Terrestrial sleeping appears to support a thermoregulatory strategy, whereas the use of a bird nest could not be empirically tested. Our observations of unique sleeping site locations used by southern bamboo lemurs further the complexity of their

  19. Is hyporheic flow an indicator for salmonid spawning site selection?

    NASA Astrophysics Data System (ADS)

    Benjankar, R. M.; Tonina, D.; Marzadri, A.; McKean, J. A.; Isaak, D.

    2015-12-01

    Several studies have investigated the role of hydraulic variables in the selection of spawning sites by salmonids. Some recent studies suggest that the intensity of the ambient hyporheic flow, that present without a salmon egg pocket, is a cue for spawning site selection, but others have argued against it. We tested this hypothesis by using a unique dataset of field surveyed spawning site locations and an unprecedented meter-scale resolution bathymetry of a 13.5 km long reach of Bear Valley Creek (Idaho, USA), an important Chinook salmon spawning stream. We used a two-dimensional surface water model to quantify stream hydraulics and a three-dimensional hyporheic model to quantify the hyporheic flows. Our results show that the intensity of ambient hyporheic flows is not a statistically significant variable for spawning site selection. Conversely, the intensity of the water surface curvature and the habitat quality, quantified as a function of stream hydraulics and morphology, are the most important variables for salmonid spawning site selection. KEY WORDS: Salmonid spawning habitat, pool-riffle system, habitat quality, surface water curvature, hyporheic flow

  20. Strategies for nest-site selection by king eiders

    USGS Publications Warehouse

    Bentzen, R.L.; Powell, A.N.; Suydam, R.S.

    2009-01-01

    Nest site selection is a critical component of reproduction and has presumably evolved in relation to predation, local resources, and microclimate. We investigated nest-site choice by king eiders (Somateria spectabilis) on the coastal plain of northern Alaska, USA, 2003-2005. We hypothesized that nest-site selection is driven by predator avoidance and that a variety of strategies including concealment, seclusion, and conspecific or inter-specific nest defense might lead to improved nesting success. We systematically searched wetland basins for king eider nests and measured habitat and social variables at nests (n = 212) and random locations (n = 493). King eiders made use of both secluded and concealed breeding strategies; logistic regression models revealed that females selected nests close to water, on islands, and in areas with high willow (Salix spp.) cover but did not select sites near conspecific or glaucous gull (Larus hyperboreus) nests. The most effective nest-placement strategy may vary depending on density and types of nest predators; seclusion is likely a mammalian-predator avoidance tactic whereas concealment may provide protection from avian predators. We recommend that managers in northern Alaska attempt to maintain wetland basins with islands and complex shorelines to provide potential nest sites in the vicinity of water. ?? The Wildlife Society.

  1. Optimization of ultrasonic transducers for selective guided wave actuation

    NASA Astrophysics Data System (ADS)

    Miszczynski, Mateusz; Packo, Pawel; Zbyrad, Paulina; Stepinski, Tadeusz; Uhl, Tadeusz; Lis, Jerzy; Wiatr, Kazimierz

    2016-04-01

    The application of guided waves using surface-bonded piezoceramic transducers for nondestructive testing (NDT) and Structural Health Monitoring (SHM) have shown great potential. However, due to difficulty in identification of individual wave modes resulting from their dispersive and multi-modal nature, selective mode excitement methods are highly desired. The presented work focuses on an optimization-based approach to design of a piezoelectric transducer for selective guided waves generation. The concept of the presented framework involves a Finite Element Method (FEM) model in the optimization process. The material of the transducer is optimized in topological sense with the aim of tuning piezoelectric properties for actuation of specific guided wave modes.

  2. Roost site selection by ring-billed and herring gulls

    USGS Publications Warehouse

    Clark, Daniel E.; Destefano, Stephen; MacKenzie, Kenneth G.; Koenen, Kiana K. G.; Whitney, Jillian J.

    2016-01-01

    Gulls (Larus spp.) commonly roost in large numbers on inland and coastal waters, yet there is little information on how or where gulls choose sites for roosting. Roost site selection can lead to water quality degradation or aviation hazards when roosts are formed on water supply reservoirs or are close to airports. Harassment programs are frequently initiated to move or relocate roosting gulls but often have mixed results because gulls are reluctant to leave or keep returning. As such, knowledge of gull roost site selection and roosting ecology has applied and ecological importance. We used satellite telemetry and an information-theoretic approach to model seasonal roost selection of ring-billed (L. delawarensis) and herring gulls (L. argentatus) in Massachusetts, USA. Our results indicated that ring-billed gulls preferred freshwater roosts and will use a variety of rivers, lakes, and reservoirs. Herring gulls regularly roosted on fresh water but used salt water roosts more often than ring-billed gulls and also roosted on a variety of land habitats. Roost modeling showed that herring and ring-billed gulls selected inland fresh water roosts based on size of the water body and proximity to their last daytime location; they selected the largest roost closest to where they ended the day. Management strategies to reduce or eliminate roosting gulls could identify and try to eliminate other habitat variables (e.g., close-by foraging sites) that are attracting gulls before attempting to relocate or redistribute (e.g., through hazing programs) roosting birds.

  3. Digital logic optimization using selection operators

    NASA Technical Reports Server (NTRS)

    Whitaker, Sterling R. (Inventor); Miles, Lowell H. (Inventor); Cameron, Eric G. (Inventor); Gambles, Jody W. (Inventor)

    2004-01-01

    According to the invention, a digital design method for manipulating a digital circuit netlist is disclosed. In one step, a first netlist is loaded. The first netlist is comprised of first basic cells that are comprised of first kernel cells. The first netlist is manipulated to create a second netlist. The second netlist is comprised of second basic cells that are comprised of second kernel cells. A percentage of the first and second kernel cells are selection circuits. There is less chip area consumed in the second basic cells than in the first basic cells. The second netlist is stored. In various embodiments, the percentage could be 2% or more, 5% or more, 10% or more, 20% or more, 30% or more, or 40% or more.

  4. Enabling Interoperable and Selective Data Sharing among Social Networking Sites

    NASA Astrophysics Data System (ADS)

    Shin, Dongwan; Lopes, Rodrigo

    With the widespread use of social networking (SN) sites and even introduction of a social component in non-social oriented services, there is a growing concern over user privacy in general, how to handle and share user profiles across SN sites in particular. Although there have been several proprietary or open source-based approaches to unifying the creation of third party applications, the availability and retrieval of user profile information are still limited to the site where the third party application is run, mostly devoid of the support for data interoperability. In this paper we propose an approach to enabling interopearable and selective data sharing among SN sites. To support selective data sharing, we discuss an authenticated dictionary (ADT)-based credential which enables a user to share only a subset of her information certified by external SN sites with applications running on an SN site. For interoperable data sharing, we propose an extension to the OpenSocial API so that it can provide an open source-based framework for allowing the ADT-based credential to be used seamlessly among different SN sites.

  5. Selection of the Mars Science Laboratory landing site

    USGS Publications Warehouse

    Golombek, M.; Grant, J.; Kipp, D.; Vasavada, A.; Kirk, Randolph L.; Fergason, Robin L.; Bellutta, P.; Calef, F.; Larsen, K.; Katayama, Y.; Huertas, A.; Beyer, R.; Chen, A.; Parker, T.; Pollard, B.; Lee, S.; Hoover, R.; Sladek, H.; Grotzinger, J.; Welch, R.; Dobrea, E. Noe; Michalski, J.; Watkins, M.

    2012-01-01

    The selection of Gale crater as the Mars Science Laboratory landing site took over five years, involved broad participation of the science community via five open workshops, and narrowed an initial >50 sites (25 by 20 km) to four finalists (Eberswalde, Gale, Holden and Mawrth) based on science and safety. Engineering constraints important to the selection included: (1) latitude (±30°) for thermal management of the rover and instruments, (2) elevation (<-1 km) for sufficient atmosphere to slow the spacecraft, (3) relief of <100-130 m at baselines of 1-1000 m for control authority and sufficient fuel during powered descent, (4) slopes of <30° at baselines of 2-5 m for rover stability at touchdown, (5) moderate rock abundance to avoid impacting the belly pan during touchdown, and (6) a radar-reflective, load-bearing, and trafficable surface that is safe for landing and roving and not dominated by fine-grained dust. Science criteria important for the selection include the ability to assess past habitable environments, which include diversity, context, and biosignature (including organics) preservation. Sites were evaluated in detail using targeted data from instruments on all active orbiters, and especially Mars Reconnaissance Orbiter. All of the final four sites have layered sedimentary rocks with spectral evidence for phyllosilicates that clearly address the science objectives of the mission. Sophisticated entry, descent and landing simulations that include detailed information on all of the engineering constraints indicate all of the final four sites are safe for landing. Evaluation of the traversabilty of the landing sites and target “go to” areas outside of the ellipse using slope and material properties information indicates that all are trafficable and “go to” sites can be accessed within the lifetime of the mission. In the final selection, Gale crater was favored over Eberswalde based on its greater diversity and potential habitability.

  6. Selection of the Mars Science Laboratory Landing Site

    NASA Astrophysics Data System (ADS)

    Golombek, M.; Grant, J.; Kipp, D.; Vasavada, A.; Kirk, R.; Fergason, R.; Bellutta, P.; Calef, F.; Larsen, K.; Katayama, Y.; Huertas, A.; Beyer, R.; Chen, A.; Parker, T.; Pollard, B.; Lee, S.; Sun, Y.; Hoover, R.; Sladek, H.; Grotzinger, J.; Welch, R.; Noe Dobrea, E.; Michalski, J.; Watkins, M.

    2012-09-01

    The selection of Gale crater as the Mars Science Laboratory landing site took over five years, involved broad participation of the science community via five open workshops, and narrowed an initial >50 sites (25 by 20 km) to four finalists (Eberswalde, Gale, Holden and Mawrth) based on science and safety. Engineering constraints important to the selection included: (1) latitude (±30°) for thermal management of the rover and instruments, (2) elevation (<-1 km) for sufficient atmosphere to slow the spacecraft, (3) relief of <100-130 m at baselines of 1-1000 m for control authority and sufficient fuel during powered descent, (4) slopes of <30° at baselines of 2-5 m for rover stability at touchdown, (5) moderate rock abundance to avoid impacting the belly pan during touchdown, and (6) a radar-reflective, load-bearing, and trafficable surface that is safe for landing and roving and not dominated by fine-grained dust. Science criteria important for the selection include the ability to assess past habitable environments, which include diversity, context, and biosignature (including organics) preservation. Sites were evaluated in detail using targeted data from instruments on all active orbiters, and especially Mars Reconnaissance Orbiter. All of the final four sites have layered sedimentary rocks with spectral evidence for phyllosilicates that clearly address the science objectives of the mission. Sophisticated entry, descent and landing simulations that include detailed information on all of the engineering constraints indicate all of the final four sites are safe for landing. Evaluation of the traversabilty of the landing sites and target "go to" areas outside of the ellipse using slope and material properties information indicates that all are trafficable and "go to" sites can be accessed within the lifetime of the mission. In the final selection, Gale crater was favored over Eberswalde based on its greater diversity and potential habitability.

  7. Efficient Simulation Budget Allocation for Selecting an Optimal Subset

    NASA Technical Reports Server (NTRS)

    Chen, Chun-Hung; He, Donghai; Fu, Michael; Lee, Loo Hay

    2008-01-01

    We consider a class of the subset selection problem in ranking and selection. The objective is to identify the top m out of k designs based on simulated output. Traditional procedures are conservative and inefficient. Using the optimal computing budget allocation framework, we formulate the problem as that of maximizing the probability of correc tly selecting all of the top-m designs subject to a constraint on the total number of samples available. For an approximation of this corre ct selection probability, we derive an asymptotically optimal allocat ion and propose an easy-to-implement heuristic sequential allocation procedure. Numerical experiments indicate that the resulting allocatio ns are superior to other methods in the literature that we tested, and the relative efficiency increases for larger problems. In addition, preliminary numerical results indicate that the proposed new procedur e has the potential to enhance computational efficiency for simulation optimization.

  8. Following the equator: division site selection in Streptococcus pneumoniae.

    PubMed

    Bramkamp, Marc

    2015-03-01

    The mechanisms that spatially regulate cytokinesis are more diverse than initially thought. In two recent publications a positive regulator of FtsZ positioning has been identified in Streptococcus pneumoniae. MapZ (LocZ) connects the division machinery with cell wall elongation, providing a simple mechanism to ensure correct division site selection.

  9. 23 CFR 1340.5 - Selection of observation sites.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., of available Fatality Analysis Reporting System (FARS) data or State fatality data approved by NHTSA...) States shall select observation sites from a database of road inventories approved by NHTSA or provided... not within a Metropolitan Statistical Area (MSA), as published by the Office of Management and...

  10. Tunnel-Site Selection by Remote Sensing Techniques

    DTIC Science & Technology

    A study of the role of remote sensing for geologic reconnaissance for tunnel-site selection was commenced. For this study, remote sensing was defined...conventional remote sensing . Future research directions are suggested, and the extension of remote sensing to include airborne passive microwave

  11. Oviposition site selection in Cactoblastis cactorum (Lepidoptera): constraints and compromises.

    PubMed

    Robertson, H G

    1987-10-01

    Oviposition by Cactoblastis cactorum on Opuntia ficus-indica and O. aurantiaca was assessed from the positioning of egg sticks on plants in the field. The number of egg sticks laid on O. ficus-indica plants was affected by: (1) plant size; (2) moth emergence near the plant; (3) cladode condition; and (4) plant conspicuousness. These factors contributed towards the clumping of egg sticks on plants. There was no apparent oviposition preference for one of the two host plant species despite the fact that egg predation was higher and fecundity lower on O. aurantiaca. The selection of a site for oviposition on the host plants was influenced by: (1) cladode condition; (2) height above ground; and (3) shelter from wind during oviposition. Succulent cladodes were the favoured sites for oviposition. The evidence suggests that in C. cactorum, oviposition site selection is largely the net result of a compromise between oviposition behaviour selected for increasing the probability of juvenile survival and oviposition behaviour selected for increasing the probability of laying the full complement of eggs. In addition, environmental and physiological factors such as wind and wing-loading, are thought to place constraints on the range of sites available for oviposition.

  12. Positively selected sites in cetacean myoglobins contribute to protein stability.

    PubMed

    Dasmeh, Pouria; Serohijos, Adrian W R; Kepp, Kasper P; Shakhnovich, Eugene I

    2013-01-01

    Since divergence ∼50 Ma ago from their terrestrial ancestors, cetaceans underwent a series of adaptations such as a ∼10-20 fold increase in myoglobin (Mb) concentration in skeletal muscle, critical for increasing oxygen storage capacity and prolonging dive time. Whereas the O2-binding affinity of Mbs is not significantly different among mammals (with typical oxygenation constants of ∼0.8-1.2 µM(-1)), folding stabilities of cetacean Mbs are ∼2-4 kcal/mol higher than for terrestrial Mbs. Using ancestral sequence reconstruction, maximum likelihood and bayesian tests to describe the evolution of cetacean Mbs, and experimentally calibrated computation of stability effects of mutations, we observe accelerated evolution in cetaceans and identify seven positively selected sites in Mb. Overall, these sites contribute to Mb stabilization with a conditional probability of 0.8. We observe a correlation between Mb folding stability and protein abundance, suggesting that a selection pressure for stability acts proportionally to higher expression. We also identify a major divergence event leading to the common ancestor of whales, during which major stabilization occurred. Most of the positively selected sites that occur later act against other destabilizing mutations to maintain stability across the clade, except for the shallow divers, where late stability relaxation occurs, probably due to the shorter aerobic dive limits of these species. The three main positively selected sites 66, 5, and 35 undergo changes that favor hydrophobic folding, structural integrity, and intra-helical hydrogen bonds.

  13. Site-specific group selection drives locally adapted group compositions.

    PubMed

    Pruitt, Jonathan N; Goodnight, Charles J

    2014-10-16

    Group selection may be defined as selection caused by the differential extinction or proliferation of groups. The socially polymorphic spider Anelosimus studiosus exhibits a behavioural polymorphism in which females exhibit either a 'docile' or 'aggressive' behavioural phenotype. Natural colonies are composed of a mixture of related docile and aggressive individuals, and populations differ in colonies' characteristic docile:aggressive ratios. Using experimentally constructed colonies of known composition, here we demonstrate that population-level divergence in docile:aggressive ratios is driven by site-specific selection at the group level--certain ratios yield high survivorship at some sites but not others. Our data also indicate that colonies responded to the risk of extinction: perturbed colonies tended to adjust their composition over two generations to match the ratio characteristic of their native site, thus promoting their long-term survival in their natal habitat. However, colonies of displaced individuals continued to shift their compositions towards mixtures that would have promoted their survival had they remained at their home sites, regardless of their contemporary environment. Thus, the regulatory mechanisms that colonies use to adjust their composition appear to be locally adapted. Our data provide experimental evidence of group selection driving collective traits in wild populations.

  14. Selection of Structures with Grid Optimization, in Multiagent Data Warehouse

    NASA Astrophysics Data System (ADS)

    Gorawski, Marcin; Bańkowski, Sławomir; Gorawski, Michał

    The query optimization problem in data base and data warehouse management systems is quite similar. Changes to Joins sequences, projections and selections, usage of indexes, and aggregations are all decided during the analysis of an execution schedule. The main goal of these changes is to decrease the query response time. The optimization operation is often dedicated to a single node. This paper proposes optimization to grid or cluster data warehouses / databases. Tests were conducted in a multi-agent environment, and the optimization focused not only on a single node but on the whole system as well. A new idea is proposed here with multi-criteria optimization that is based on user-given parameters. Depending on query time, result admissible errors, and the level of system usage, task results were obtained along with grid optimization.

  15. Chemical tailoring of teicoplanin with site-selective reactions.

    PubMed

    Pathak, Tejas P; Miller, Scott J

    2013-06-05

    Semisynthesis of natural product derivatives combines the power of fermentation with orthogonal chemical reactions. Yet, chemical modification of complex structures represents an unmet challenge, as poor selectivity often undermines efficiency. The complex antibiotic teicoplanin eradicates bacterial infections. However, as resistance emerges, the demand for improved analogues grows. We have discovered chemical reactions that achieve site-selective alteration of teicoplanin. Utilizing peptide-based additives that alter reaction selectivities, certain bromo-teicoplanins are accessible. These new compounds are also scaffolds for selective cross-coupling reactions, enabling further molecular diversification. These studies enable two-step access to glycopeptide analogues not available through either biosynthesis or rapid total chemical synthesis alone. The new compounds exhibit a spectrum of activities, revealing that selective chemical alteration of teicoplanin may lead to analogues with attenuated or enhanced antibacterial properties, in particular against vancomycin- and teicoplanin-resistant strains.

  16. Learning natural selection from the site frequency spectrum.

    PubMed

    Ronen, Roy; Udpa, Nitin; Halperin, Eran; Bafna, Vineet

    2013-09-01

    Genetic adaptation to external stimuli occurs through the combined action of mutation and selection. A central problem in genetics is to identify loci responsive to specific selective constraints. Many tests have been proposed to identify the genomic signatures of natural selection by quantifying the skew in the site frequency spectrum (SFS) under selection relative to neutrality. We build upon recent work that connects many of these tests under a common framework, by describing how selective sweeps affect the scaled SFS. We show that the specific skew depends on many attributes of the sweep, including the selection coefficient and the time under selection. Using supervised learning on extensive simulated data, we characterize the features of the scaled SFS that best separate different types of selective sweeps from neutrality. We develop a test, SFselect, that consistently outperforms many existing tests over a wide range of selective sweeps. We apply SFselect to polymorphism data from a laboratory evolution experiment of Drosophila melanogaster adapted to hypoxia and identify loci that strengthen the role of the Notch pathway in hypoxia tolerance, but were missed by previous approaches. We further apply our test to human data and identify regions that are in agreement with earlier studies, as well as many novel regions.

  17. Periodical cicadas use light for oviposition site selection.

    PubMed

    Yang, Louie H

    2006-12-07

    Organisms use incomplete information from local experience to assess the suitability of potential habitat sites over a wide range of spatial and temporal scales. Although ecologists have long recognized the importance of spatial scales in habitat selection, few studies have investigated the temporal scales of habitat selection. In particular, cues in the immediate environment may commonly provide indirect information about future habitat quality. In periodical cicadas (Magicicada spp.), oviposition site selection represents a very long-term habitat choice. Adult female cicadas insert eggs into tree branches during a few weeks in the summer of emergence, but their oviposition choices determine the underground habitats of root-feeding nymphs over the following 13 or 17 years. Here, field experiments are used to show that female cicadas use the local light environment of host trees during the summer of emergence to select long-term host trees. Light environments may also influence oviposition microsite selection within hosts, suggesting a potential behavioural mechanism for associating solar cues with host trees. In contrast, experimental nutrient enrichment of host trees did not influence cicada oviposition densities. These findings suggest that the light environments around host trees may provide a robust predictor of host tree quality in the near future. This habitat selection may influence the spatial distribution of several cicada-mediated ecological processes in eastern North American forests.

  18. Retroviral integration: Site matters: Mechanisms and consequences of retroviral integration site selection.

    PubMed

    Demeulemeester, Jonas; De Rijck, Jan; Gijsbers, Rik; Debyser, Zeger

    2015-11-01

    Here, we review genomic target site selection during retroviral integration as a multistep process in which specific biases are introduced at each level. The first asymmetries are introduced when the virus takes a specific route into the nucleus. Next, by co-opting distinct host cofactors, the integration machinery is guided to particular chromatin contexts. As the viral integrase captures a local target nucleosome, specific contacts introduce fine-grained biases in the integration site distribution. In vivo, the established population of proviruses is subject to both positive and negative selection, thereby continuously reshaping the integration site distribution. By affecting stochastic proviral expression as well as the mutagenic potential of the virus, integration site choice may be an inherent part of the evolutionary strategies used by different retroviruses to maximise reproductive success.

  19. Fast Simulation and Optimization Tool to Explore Selective Neural Stimulation.

    PubMed

    Dali, Mélissa; Rossel, Olivier; Guiraud, David

    2016-06-13

    In functional electrical stimulation, selective stimulation of axons is desirable to activate a specific target, in particular muscular function. This implies to simulate a fascicule without activating neighboring ones i.e. to be spatially selective. Spatial selectivity is achieved by the use of multicontact cuff electrodes over which the stimulation current is distributed. Because of the large number of parameters involved, numerical simulations provide a way to find and optimize electrode configuration. The present work offers a computation effective scheme and associated tool chain capable of simulating electrode-nerve interface and find the best spread of current to achieve spatial selectivity.

  20. Fast Simulation and Optimization Tool to Explore Selective Neural Stimulation

    PubMed Central

    Dali, Mélissa; Rossel, Olivier; Guiraud, David

    2016-01-01

    In functional electrical stimulation, selective stimulation of axons is desirable to activate a specific target, in particular muscular function. This implies to simulate a fascicule without activating neighboring ones i.e. to be spatially selective. Spatial selectivity is achieved by the use of multicontact cuff electrodes over which the stimulation current is distributed. Because of the large number of parameters involved, numerical simulations provide a way to find and optimize electrode configuration. The present work offers a computation effective scheme and associated tool chain capable of simulating electrode-nerve interface and find the best spread of current to achieve spatial selectivity. PMID:27990231

  1. Two mechanisms of ion selectivity in protein binding sites.

    PubMed

    Yu, Haibo; Noskov, Sergei Yu; Roux, Benoît

    2010-11-23

    A theoretical framework is presented to clarify the molecular determinants of ion selectivity in protein binding sites. The relative free energy of a bound ion is expressed in terms of the main coordinating ligands coupled to an effective potential of mean force representing the influence of the rest of the protein. The latter is separated into two main contributions. The first includes all the forces keeping the ion and the coordinating ligands confined to a microscopic subvolume but does not prevent the ligands from adapting to a smaller or larger ion. The second regroups all the remaining forces that control the precise geometry of the coordinating ligands best adapted to a given ion. The theoretical framework makes it possible to delineate two important limiting cases. In the limit where the geometric forces are dominant (rigid binding site), ion selectivity is controlled by the ion-ligand interactions within the matching cavity size according to the familiar "snug-fit" mechanism of host-guest chemistry. In the limit where the geometric forces are negligible, the ion and ligands behave as a "confined microdroplet" that is free to fluctuate and adapt to ions of different sizes. In this case, ion selectivity is set by the interplay between ion-ligand and ligand-ligand interactions and is controlled by the number and the chemical type of ion-coordinating ligands. The framework is illustrated by considering the ion-selective binding sites in the KcsA channel and the LeuT transporter.

  2. Discrete Biogeography Based Optimization for Feature Selection in Molecular Signatures.

    PubMed

    Liu, Bo; Tian, Meihong; Zhang, Chunhua; Li, Xiangtao

    2015-04-01

    Biomarker discovery from high-dimensional data is a complex task in the development of efficient cancer diagnoses and classification. However, these data are usually redundant and noisy, and only a subset of them present distinct profiles for different classes of samples. Thus, selecting high discriminative genes from gene expression data has become increasingly interesting in the field of bioinformatics. In this paper, a discrete biogeography based optimization is proposed to select the good subset of informative gene relevant to the classification. In the proposed algorithm, firstly, the fisher-markov selector is used to choose fixed number of gene data. Secondly, to make biogeography based optimization suitable for the feature selection problem; discrete migration model and discrete mutation model are proposed to balance the exploration and exploitation ability. Then, discrete biogeography based optimization, as we called DBBO, is proposed by integrating discrete migration model and discrete mutation model. Finally, the DBBO method is used for feature selection, and three classifiers are used as the classifier with the 10 fold cross-validation method. In order to show the effective and efficiency of the algorithm, the proposed algorithm is tested on four breast cancer dataset benchmarks. Comparison with genetic algorithm, particle swarm optimization, differential evolution algorithm and hybrid biogeography based optimization, experimental results demonstrate that the proposed method is better or at least comparable with previous method from literature when considering the quality of the solutions obtained.

  3. A Potent and Site-Selective Agonist of TRPA1.

    PubMed

    Takaya, Junichiro; Mio, Kazuhiro; Shiraishi, Takuya; Kurokawa, Tatsuki; Otsuka, Shinya; Mori, Yasuo; Uesugi, Motonari

    2015-12-23

    TRPA1 is a member of the transient receptor potential (TRP) cation channel family that is expressed primarily on sensory neurons. This chemosensor is activated through covalent modification of multiple cysteine residues with a wide range of reactive compounds including allyl isothiocyanate (AITC), a spicy component of wasabi. The present study reports on potent and selective agonists of TRPA1, discovered through screening 1657 electrophilic molecules. In an effort to validate the mode of action of hit molecules, we noted a new TRPA1-selective agonist, JT010 (molecule 1), which opens the TRPA1 channel by covalently and site-selectively binding to Cys621 (EC50 = 0.65 nM). The results suggest that a single modification of Cys621 is sufficient to open the TRPA1 channel. The TRPA1-selective probe described herein might be useful for further mechanistic studies of TRPA1 activation.

  4. Linkage disequilibrium extends across putative selected sites in FOXP2.

    PubMed

    Ptak, Susan E; Enard, Wolfgang; Wiebe, Victor; Hellmann, Ines; Krause, Johannes; Lachmann, Michael; Pääbo, Svante

    2009-10-01

    Polymorphism data in humans suggest that the gene encoding the transcription factor FOXP2, which influences speech and language development, has been subject to a selective sweep within the last 260,000 years. It has been proposed that one or both of two substitutions that occurred on the human evolutionary lineage and changed amino acids were the targets for selection. In apparent contradiction to this is the observation that these substitutions are present in Neandertals who diverged from humans maybe 300,000-400,000 years ago. We have collected polymorphism data upstream and downstream of the substitutions. Contrary to what is expected, following a selective sweep, we find that the haplotypes extend across the two sites. We discuss possible explanations for these observations. One of them is that the selective sweep reflected in FOXP2 polymorphism data was not associated with the two amino acid substitutions.

  5. Selection of the Mars Exploration Rover landing sites

    USGS Publications Warehouse

    Golombek, M.P.; Grant, J. A.; Parker, T.J.; Kass, D.M.; Crisp, J.A.; Squyres, S. W.; Haldemann, A.F.C.; Adler, M.; Lee, W.J.; Bridges, N.T.; Arvidson, R. E.; Carr, M.H.; Kirk, R.L.; Knocke, P.C.; Roncoli, R.B.; Weitz, C.M.; Schofield, J.T.; Zurek, R.W.; Christensen, P.R.; Fergason, R.L.; Anderson, F.S.; Rice, J. W.

    2003-01-01

    The selection of Meridiani Planum and Gusev crater as the Mars Exploration Rover landing sites took over 2 years, involved broad participation of the science community via four open workshops, and narrowed an initial ???155 potential sites (80-300 ?? 30 km) to four finalists based on science and safety. Engineering constraints important to the selection included (1) latitude (10??N- 15??S) for maximum solar power, (2) elevation (less than - 1.3 km) for sufficient atmosphere to slow the lander, (3) low horizontal winds, shear, and turbulence in the last few kilometers to minimize horizontal velocity, (4) low 10-m-scale slopes to reduce airbag spin-up and bounce, (5) moderate rock abundance to reduce abrasion or strokeout of the airbags, and (6) a radar-reflective, load-bearing, and trafficable surface safe for landing and roving that is not dominated by fine-grained dust. The evaluation of sites utilized existing as well as targeted orbital information acquired from the Mars Global Surveyor and Mars Odyssey. Three of the final four landing sites show strong evidence for surface processes involving water and appear capable of addressing the science objectives of the missions, which are to determine the aqueous, climatic, and geologic history of sites on Mars where conditions may have been favorable to the preservation of evidence of possible prebiotic or biotic processes. The evaluation of science criteria placed Meridiani and Gusev as the highest-priority sites. The evaluation of the three most critical safety criteria (10-m-scale slopes, rocks, and winds) and landing simulation results indicated that Meridiani and Elysium Planitia are the safest sites, followed by Gusev and Isidis Planitia. Copyright 2003 by the American Geophysical Union.

  6. Selection of the Mars Exploration Rover landing sites

    NASA Astrophysics Data System (ADS)

    Golombek, M. P.; Grant, J. A.; Parker, T. J.; Kass, D. M.; Crisp, J. A.; Squyres, S. W.; Haldemann, A. F. C.; Adler, M.; Lee, W. J.; Bridges, N. T.; Arvidson, R. E.; Carr, M. H.; Kirk, R. L.; Knocke, P. C.; Roncoli, R. B.; Weitz, C. M.; Schofield, J. T.; Zurek, R. W.; Christensen, P. R.; Fergason, R. L.; Anderson, F. S.; Rice, J. W.

    2003-12-01

    The selection of Meridiani Planum and Gusev crater as the Mars Exploration Rover landing sites took over 2 years, involved broad participation of the science community via four open workshops, and narrowed an initial ~155 potential sites (80-300 × 30 km) to four finalists based on science and safety. Engineering constraints important to the selection included (1) latitude (10°N-15°S) for maximum solar power, (2) elevation (less than -1.3 km) for sufficient atmosphere to slow the lander, (3) low horizontal winds, shear, and turbulence in the last few kilometers to minimize horizontal velocity, (4) low 10-m-scale slopes to reduce airbag spin-up and bounce, (5) moderate rock abundance to reduce abrasion or strokeout of the airbags, and (6) a radar-reflective, load-bearing, and trafficable surface safe for landing and roving that is not dominated by fine-grained dust. The evaluation of sites utilized existing as well as targeted orbital information acquired from the Mars Global Surveyor and Mars Odyssey. Three of the final four landing sites show strong evidence for surface processes involving water and appear capable of addressing the science objectives of the missions, which are to determine the aqueous, climatic, and geologic history of sites on Mars where conditions may have been favorable to the preservation of evidence of possible prebiotic or biotic processes. The evaluation of science criteria placed Meridiani and Gusev as the highest-priority sites. The evaluation of the three most critical safety criteria (10-m-scale slopes, rocks, and winds) and landing simulation results indicated that Meridiani and Elysium Planitia are the safest sites, followed by Gusev and Isidis Planitia.

  7. Site selection modeling system for a production facility at Savannah River site

    SciTech Connect

    Shedrow, C.B.; Shedrow, D.M.

    1996-12-31

    The Savannah River site (SRS) is located along the Savannah River in southwestern South Carolina and encompasses an area of {approximately}832 km (198 344 acres). Major land covers include evergreen and deciduous forests, surface water, wetlands, and administrative/industrial areas. Less than 10% of the site`s surface area is developed. Several endangered and threatened species are found on the SRS, including the red-cockaded woodpecker, the southern bald eagle, the wood stork, and the smooth purple coneflower. With the cessation of the Cold War, the traditional defense-related missions at the SRS have been significantly reduced. The implementation of new missions at the SRS will require the utilization of effective siting and prioritization methodologies to ensure the best use of available land resources and protection of the environment. The objective of this paper is to describe the utilization of the Site Selection Modeling System (SSMS) for the selection of potential industrial development sites within the SRS. The SSMS is a raster geographic information system (GIS)-based system that integrates the graphical interface ArcView 2.1 with the GRID modeling functionality of ARC/INFO. The proposed industrial development being sited is a linear accelerator, which will be used for the accelerator production of tritium.

  8. Effects of spatial disturbance on common loon nest site selection and territory success

    USGS Publications Warehouse

    McCarthy, K.P.; DeStefano, S.

    2011-01-01

    The common loon (Gavia immer) breeds during the summer on northern lakes and water bodies that are also often desirable areas for aquatic recreation and human habitation. In northern New England, we assessed how the spatial nature of disturbance affects common loon nest site selection and territory success. We found through classification and regression analysis that distance to and density of disturbance factors can be used to classify observed nest site locations versus random points, suggesting that these factors affect loon nest site selection (model 1: Correct classification = 75%, null = 50%, K = 0.507, P < 0.001; model 2: Correct classification = 78%, null = 50%, K = 0.551, P < 0.001). However, in an exploratory analysis, we were unable to show a relation between spatial disturbance variables and breeding success (P = 0.595, R 2 = 0.436), possibly because breeding success was so low during the breeding seasons of 2007-2008. We suggest that by selecting nest site locations that avoid disturbance factors, loons thereby limit the effect that disturbance will have on their breeding success. Still, disturbance may force loons to use sub-optimal nesting habitat, limiting the available number of territories, and overall productivity. We advise that management efforts focus on limiting disturbance factors to allow breeding pairs access to the best nesting territories, relieving disturbance pressures that may force sub-optimal nest placement. ?? 2011 The Wildlife Society.

  9. SITE CHARACTERIZATION AND SELECTION GUIDELINES FOR GEOLOGICAL CARBON SEQUESTRATION

    SciTech Connect

    Friedmann, S J

    2007-08-31

    Carbon capture and sequestration (CCS) is a key technology pathway to substantial reduction of greenhouse gas emissions for the state of California and the western region. Current estimates suggest that the sequestration resource of the state is large, and could safely and effectively accept all of the emissions from large CO2 point sources for many decades and store them indefinitely. This process requires suitable sites to sequester large volumes of CO2 for long periods of time. Site characterization is the first step in this process, and the state will ultimately face regulatory, legal, and technical questions as commercial CCS projects develop and commence operations. The most important aspects of site characterizations are injectivity, capacity, and effectiveness. A site can accept at a high rate a large volume of CO2 and store it for a long time is likely to serve as a good site for geological carbon sequestration. At present, there are many conventional technologies and approaches that can be used to estimate, quantify, calculate, and assess the viability of a sequestration site. Any regulatory framework would need to rely on conventional, easily executed, repeatable methods to inform the site selection and permitting process. The most important targets for long-term storage are deep saline formations and depleted oil and gas fields. The primary CO2 storage mechanisms for these targets are well understood enough to plan operations and simulate injection and long-term fate of CO2. There is also a strong understanding of potential geological and engineering hazards for CCS. These hazards are potential pathway to CO2 leakage, which could conceivably result in negative consequences to health and the environmental. The risks of these effects are difficult to quantify; however, the hazards themselves are sufficiently well understood to identify, delineate, and manage those risks effectively. The primary hazard elements are wells and faults, but may include other

  10. GIS-based approach for optimized siting of municipal solid waste landfill

    SciTech Connect

    Sumathi, V.R. Natesan, Usha; Sarkar, Chinmoy

    2008-11-15

    The exponential rise in the urban population of the developing countries in the past few decades and the resulting accelerated urbanization phenomenon has brought to the fore the necessity to develop environmentally sustainable and efficient waste management systems. Sanitary landfill constitutes one of the primary methods of municipal solid waste disposal. Optimized siting decisions have gained considerable importance in order to ensure minimum damage to the various environmental sub-components as well as reduce the stigma associated with the residents living in its vicinity, thereby enhancing the overall sustainability associated with the life cycle of a landfill. This paper addresses the siting of a new landfill using a multi-criteria decision analysis (MCDA) and overlay analysis using a geographic information system (GIS). The proposed system can accommodate new information on the landfill site selection by updating its knowledge base. Several factors are considered in the siting process including geology, water supply resources, land use, sensitive sites, air quality and groundwater quality. Weightings were assigned to each criterion depending upon their relative importance and ratings in accordance with the relative magnitude of impact. The results from testing the system using different sites show the effectiveness of the system in the selection process.

  11. GIS-based approach for optimized siting of municipal solid waste landfill.

    PubMed

    Sumathi, V R; Natesan, Usha; Sarkar, Chinmoy

    2008-11-01

    The exponential rise in the urban population of the developing countries in the past few decades and the resulting accelerated urbanization phenomenon has brought to the fore the necessity to develop environmentally sustainable and efficient waste management systems. Sanitary landfill constitutes one of the primary methods of municipal solid waste disposal. Optimized siting decisions have gained considerable importance in order to ensure minimum damage to the various environmental sub-components as well as reduce the stigma associated with the residents living in its vicinity, thereby enhancing the overall sustainability associated with the life cycle of a landfill. This paper addresses the siting of a new landfill using a multi-criteria decision analysis (MCDA) and overlay analysis using a geographic information system (GIS). The proposed system can accommodate new information on the landfill site selection by updating its knowledge base. Several factors are considered in the siting process including geology, water supply resources, land use, sensitive sites, air quality and groundwater quality. Weightings were assigned to each criterion depending upon their relative importance and ratings in accordance with the relative magnitude of impact. The results from testing the system using different sites show the effectiveness of the system in the selection process.

  12. Site-Selective Trimetallic Heterogeneous Nanostructures for Enhanced Electrocatalytic Performance.

    PubMed

    Xie, Xiaobin; Gao, Guanhui; Kang, Shendong; Shibayama, Tamaki; Lei, Yanhua; Gao, Duyang; Cai, Lintao

    2015-10-07

    Trimetallic Au/Ag/Pt hetero-nanostructures (AAPHNs) with distinctive, designed morphology are synthesized by galvanic replacement reaction and a site-selective strategy. The three metals present on the surface are shown to act synergistically to enhance the electro-catalytic performance and durability for methanol oxidation. The described structural modification of the nanocomposites increases the range of potential applications to include both the oxygen reduction reaction in fuel cells and photocatalysis of the hydrogen evolution reaction.

  13. Site-selective Alkane Dehydrogenation of Fatty Acids

    DTIC Science & Technology

    2011-12-14

    dehydrogenation of fatty acids Contract/Grant#: FA9550-10-1-0532 Final Reporting Period: 15 September 2011 to 14 September 2011...directly incorporate fatty acids into the ligand. The preparation of the acyl phosphines (1-5) was easily accomplished starting from the corresponding...AFOSR Final Report Final Report 
 The proposed research examines the site-selective dehydrogenation of alkanes. The alkanes employed were fatty

  14. Mars sample return: Site selection and sample acquisition study

    NASA Technical Reports Server (NTRS)

    Nickle, N. (Editor)

    1980-01-01

    Various vehicle and mission options were investigated for the continued exploration of Mars; the cost of a minimum sample return mission was estimated; options and concepts were synthesized into program possibilities; and recommendations for the next Mars mission were made to the Planetary Program office. Specific sites and all relevant spacecraft and ground-based data were studied in order to determine: (1) the adequacy of presently available data for identifying landing sities for a sample return mission that would assure the acquisition of material from the most important geologic provinces of Mars; (2) the degree of surface mobility required to assure sample acquisition for these sites; (3) techniques to be used in the selection and drilling of rock a samples; and (4) the degree of mobility required at the two Viking sites to acquire these samples.

  15. Commercial facility site selection simulating based on MAS

    NASA Astrophysics Data System (ADS)

    Chao, Yi; Li, Qingquan; Zheng, Guizhou

    2008-10-01

    The location of commercial facility decides the benefit of the operator to a large degree. Existing location methods can express the static relationships between site selection result and location factors, but there still are some limites when express the dynamic and uncertain relationship between them. Hence, a dynamic, stochastic and forecastable location model should be built which can introduce the customer's behavior into the model and combine the macro pattern and micro spatial interaction. So the authors proposes Geosim-LM based on MAS. Geosim-LM has 3 kinds of agents, CustAgent, SiteAgent and GovAgent. They represent the customers, commercial fercilities and government. The land type, land price and traffic are the model environment. Then Geosim-LM is applied in the bank branches site evaluation and selection in Liwan district, Guangzhou. In existing bank branches site evaluation, there are 70% consistent in score grade between result of Geosim-LM after 200 round runing and actual rebust location. It proves the model is reliable and feasible. The conclusions can be get from the paper. MAS have advantages in location choice than existed methods. The result of Geosim-LM running can powerfully proves that building location model based on MAS is feasible.

  16. Gas Hydrate Research Site Selection and Operational Research Plans

    NASA Astrophysics Data System (ADS)

    Collett, T. S.; Boswell, R. M.

    2009-12-01

    In recent years it has become generally accepted that gas hydrates represent a potential important future energy resource, a significant drilling and production hazard, a potential contributor to global climate change, and a controlling factor in seafloor stability and landslides. Research drilling and coring programs carried out by the Ocean Drilling Program (ODP), the Integrated Ocean Drilling Program (IODP), government agencies, and several consortia have contributed greatly to our understanding of the geologic controls on the occurrence of gas hydrates in marine and permafrost environments. For the most part, each of these field projects were built on the lessons learned from the projects that have gone before them. One of the most important factors contributing to the success of some of the more notable gas hydrate field projects has been the close alignment of project goals with the processes used to select the drill sites and to develop the project’s operational research plans. For example, IODP Expedition 311 used a transect approach to successfully constrain the overall occurrence of gas hydrate within the range of geologic environments within a marine accretionary complex. Earlier gas hydrate research drilling, including IODP Leg 164, were designed primarily to assess the occurrence and nature of marine gas hydrate systems, and relied largely on the presence of anomalous seismic features, including bottom-simulating reflectors and “blanking zones”. While these projects were extremely successful, expeditions today are being increasingly mounted with the primary goal of prospecting for potential gas hydrate production targets, and site selection processes designed to specifically seek out anomalously high-concentrations of gas hydrate are needed. This approach was best demonstrated in a recently completed energy resource focused project, the Gulf of Mexico Gas Hydrate Joint Industry Project Leg II (GOM JIP Leg II), which featured the collection of a

  17. Selecting Landing Sites for the 2009 Mars Science Laboratory

    NASA Astrophysics Data System (ADS)

    Grant, J. A.; Golombek, M. P.; Vasavada, A. R.; Watkins, M. M.; Mars Landing Site Steering Committee

    2006-12-01

    Landing site selection for the 2009 Mars Science Laboratory (MSL) is underway and includes a series of open workshops for soliciting science community input regarding the landing site. The first workshop was held in Spring 2006 and focused on prioritizing 33 proposed sites for imaging by orbital spacecraft. It should be noted that the number of potential landing sites is high because MSL entry, descent, and landing (EDL) capabilities enable a small landing error circle (20 km in diameter), high landing site altitude (below 1 km, MOLA datum), and wide latitudes (plus/minus 45 degrees). The primary scientific goal of MSL is to assess the present and past habitability of environments accessed by the mission. In particular, MSL will assess the biological potential of the landing site, characterize the geology and geochemistry at appropriate spatial scales, investigate planetary processes that influence habitability, including the role of water, and characterize the broad spectrum of surface radiation. The geological, chemical, and/or biological evidence for habitability should be expected to be preserved for, accessible to and interpretable by the MSL investigations at the landing site. Because landing safely is paramount, all engineering constraints for the mission must be adhered to for a proposed site to be viewed favorably. For example, areas with potentially high winds will need to be compared with landing system tolerance during development. Slopes across length scales of 2 to 5 km, 20 meters, and 5 meters must be less than 3 degrees, 15 degrees, and 15 degrees, respectively. Rocks at the landing site should be less than 0.6 m high and in intermediate to lower abundance terrains. The landing surface must be load-bearing, radar reflective, trafficable and not be dominated by dust. Persistent cold surface temperatures and CO2 frost will negatively impact performance and areas with very low thermal inertia and very high albedo are excluded. Finally planetary

  18. Multidimensional Adaptive Testing with Optimal Design Criteria for Item Selection

    ERIC Educational Resources Information Center

    Mulder, Joris; van der Linden, Wim J.

    2009-01-01

    Several criteria from the optimal design literature are examined for use with item selection in multidimensional adaptive testing. In particular, it is examined what criteria are appropriate for adaptive testing in which all abilities are intentional, some should be considered as a nuisance, or the interest is in the testing of a composite of the…

  19. Training set optimization under population structure in genomic selection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The optimization of the training set (TRS) in genomic selection (GS) has received much interest in both animal and plant breeding, because it is critical to the accuracy of the prediction models. In this study, five different TRS sampling algorithms, stratified sampling, mean of the Coefficient of D...

  20. Optimal Financial Aid Policies for a Selective University.

    ERIC Educational Resources Information Center

    Ehrenberg, Ronald G.; Sherman, Daniel R.

    1984-01-01

    This paper provides a model of optimal financial aid policies for a selective university. The model implies that the financial aid package to be offered to each category of admitted applicants depends on the elasticity of the fraction who accept offers of admission with respect to the financial aid package offered them. (Author/SSH)

  1. Physiological and ecological consequences of sleeping-site selection by the Galapagos land iguana (Conolophus pallidus)

    SciTech Connect

    Christian, K.A.; Tracy, C.R.

    1984-01-01

    Field observations and biophysical models were combined to analyze sleeping-site selection by Galapagos land iguanas (Conolophus pallidus). Iguanas slept in different kinds of sleeping sites during different seasons. In the coolest season (garua), adult land iguanas were found in sleeping sites that were warmer than the coolest sites available. This may be because the garua season (cool, overcast, and foggy) is a time when environmental conditions mitigate against rapid warm-up in the mornings, so lizards may regulate nighttime body temperatures so that it is easier to warm up to preferred daytime body temperatures. In the warmest season, adult iguanas were found in the coolest sleeping sites available. This observation is consistent with hypotheses of voluntary hypothermia, which can be advantageous in energy conservation and in avoiding detrimental effects associated with maintenance of constant body temperatures throughout the day and night. Juvenile iguanas were found sleeping in rock crevices regardless of the ambient thermal environments. Such sites are likely to be important as refugia for this life stage, which, unlike the adult stage, is vulnerable to predation. It was concluded that selection of sleeping sites is a process that may help in avoidance of predation, optimization of body temperature at the end of the sleeping period, and reduction of metabolic costs during sleeping. The importance of some of these factors may change with the thermal milieu (e.g., season).

  2. Resource evaluation and site selection for microalgae production systems

    SciTech Connect

    Maxwell, E.L.; Folger, A.G.; Hogg, S.E.

    1985-05-01

    Climate, land, and water resource requirements of microalgae production systems (MPS) were examined relative to construction costs, operating costs, and biomass productivity. The objective was the stratification of the southwestern United States into zones of relative suitability for MPS. Maps of climate (insolation, freeze-free period, precipitation, evaporation, thunderstorm days), land (use/cover, ownership, slope), and water (saline groundwater) resource parameters were obtained. These maps were transformed into digital overlays permitting the cell-by-cell compositing of selected resource parameters to form maps representing relative productivity, make-up water, climate suitability, land suitability, water suitability, and overall suitability. The Southwest was selected for this study because of its high levels of insolation, saline water resources, and large areas of relatively low valued land. The stratification maps cannot be used for the selection of specific sites because of their low resolution (12,455-acre cells). They can be used to guide future resource studies and site selection efforts, however, by limiting these efforts to the most suitable regions. Future efforts should concentrate on saline water resources, for which only limited data are currently available. 13 refs., 44 figs., 5 tabs.

  3. Site-selective chemical cleavage of peptide bonds.

    PubMed

    Elashal, Hader E; Raj, Monika

    2016-05-07

    Site-selective cleavage of extremely unreactive peptide bonds is a very important chemical modification that provides invaluable information regarding protein sequence, and it acts as a modulator of protein structure and function for therapeutic applications. For controlled and selective cleavage, a daunting task, chemical reagents must selectively recognize or bind to one or more amino acid residues in the peptide chain and selectively cleave a peptide bond. Building on this principle, we have developed an approach that utilizes a chemical reagent to selectively modify the serine residue in a peptide chain and leads to the cleavage of a peptide backbone at the N-terminus of the serine residue. After cleavage, modified residues can be converted back to the original fragments. This method exhibits broad substrate scope and selectively cleaves various bioactive peptides with post-translational modifications (e.g. N-acetylation and -methylation) and mutations (d- and β-amino acids), which are a known cause of age related diseases.

  4. Ultra-fast fluence optimization for beam angle selection algorithms

    NASA Astrophysics Data System (ADS)

    Bangert, M.; Ziegenhein, P.; Oelfke, U.

    2014-03-01

    Beam angle selection (BAS) including fluence optimization (FO) is among the most extensive computational tasks in radiotherapy. Precomputed dose influence data (DID) of all considered beam orientations (up to 100 GB for complex cases) has to be handled in the main memory and repeated FOs are required for different beam ensembles. In this paper, the authors describe concepts accelerating FO for BAS algorithms using off-the-shelf multiprocessor workstations. The FO runtime is not dominated by the arithmetic load of the CPUs but by the transportation of DID from the RAM to the CPUs. On multiprocessor workstations, however, the speed of data transportation from the main memory to the CPUs is non-uniform across the RAM; every CPU has a dedicated memory location (node) with minimum access time. We apply a thread node binding strategy to ensure that CPUs only access DID from their preferred node. Ideal load balancing for arbitrary beam ensembles is guaranteed by distributing the DID of every candidate beam equally to all nodes. Furthermore we use a custom sorting scheme of the DID to minimize the overall data transportation. The framework is implemented on an AMD Opteron workstation. One FO iteration comprising dose, objective function, and gradient calculation takes between 0.010 s (9 beams, skull, 0.23 GB DID) and 0.070 s (9 beams, abdomen, 1.50 GB DID). Our overall FO time is < 1 s for small cases, larger cases take ~ 4 s. BAS runs including FOs for 1000 different beam ensembles take ~ 15-70 min, depending on the treatment site. This enables an efficient clinical evaluation of different BAS algorithms.

  5. Optimal selection of nodes to propagate influence on networks

    NASA Astrophysics Data System (ADS)

    Sun, Yifan

    2016-11-01

    How to optimize the spreading process on networks has been a hot issue in complex networks, marketing, epidemiology, finance, etc. In this paper, we investigate a problem of optimizing locally the spreading: identifying a fixed number of nodes as seeds which would maximize the propagation of influence to their direct neighbors. All the nodes except the selected seeds are assumed not to spread their influence to their neighbors. This problem can be mapped onto a spin glass model with a fixed magnetization. We provide a message-passing algorithm based on replica symmetrical mean-field theory in statistical physics, which can find the nearly optimal set of seeds. Extensive numerical results on computer-generated random networks and real-world networks demonstrate that this algorithm has a better performance than several other optimization algorithms.

  6. Field site selection: getting it right first time around.

    PubMed

    Malcolm, Colin A; El Sayed, Badria; Babiker, Ahmed; Girod, Romain; Fontenille, Didier; Knols, Bart G J; Nugud, Abdel Hameed; Benedict, Mark Q

    2009-11-16

    The selection of suitable field sites for integrated control of Anopheles mosquitoes using the sterile insect technique (SIT) requires consideration of the full gamut of factors facing most proposed control strategies, but four criteria identify an ideal site: 1) a single malaria vector, 2) an unstructured, relatively low density target population, 3) isolation of the target population and 4) actual or potential malaria incidence. Such a site can exist in a diverse range of situations or can be created. Two contrasting SIT field sites are examined here: the desert-flanked Dongola Reach of the Nile River in Northern State, Sudan, where malaria is endemic, and the island of La Reunion, where autochthonous malaria is rare but risk is persistent. The single malaria-transmitting vector at both sites is Anopheles arabiensis. In Sudan, the target area is a narrow 500 km corridor stretching from the rocky terrain at the Fourth Cataract--just above the new Merowe Dam, to the northernmost edge of the species range, close to Egypt. Vector distribution and temporal changes in density depend on the Nile level, ambient temperature and human activities. On La Reunion, the An. arabiensis population is coastal, limited and divided into three areas by altitude and exposure to the trade winds on the east coast. Mosquito vectors for other diseases are an issue at both sites, but of primary importance on La Reunion due to the recent chikungunya epidemic. The similarities and differences between these two sites in terms of suitability are discussed in the context of area-wide integrated vector management incorporating the SIT.

  7. Selection and Characterization of Landing Sites for Chandrayaan-2 Lander

    NASA Astrophysics Data System (ADS)

    Gopala Krishna, Barla; Amitabh, Amitabh; Srinivasan, T. P.; Karidhal, Ritu; Nagesh, G.; Manjusha, N.

    2016-07-01

    Indian Space Research Organisation has planned the second mission to moon known as Chandrayaan-2, which consists of an Orbiter, a Lander and a Rover. This will be the first soft landing mission of India on lunar surface. The Orbiter, Lander and Rover individually will carry scientific payloads that enhance the scientific objectives of Chandrayaan-2. The Lander soft lands on the lunar surface and subsequently Lander & Rover will carry on with the payload activities on the moon surface. Landing Site identification based on the scientific and engineering constrains of lander plays an important role in success of a mission. The Lander poses some constraints because of its engineering design for the selection of the landing site and on the other hand the landing site / region imparts some constrain on the Lander. The various constraints that have to be considered for the study of the landing site are Local slope, Sun illumination during mission life, Radio communication with the Earth, Global slope towards equator, Boulders size, Crater density and boulder distribution. This paper describes the characterization activities of the different landing locations which have been studied for Chandrayaan-2 Lander. The sites have been studied both in the South Polar and North Polar regions of the moon on the near side. The Engineering Constraints at the sites due to the Lander, Factors that affect mission life (i.e. illumination at the location), Factors influencing communication to earth (i.e. RF visibility) & Shadow movements have been studied at these locations and zones that are favourable for landing have been short listed. This paper gives methodology of these studies along with the results of the characteristics of all the sites and the recommendations for further action in finalizing the landing area.

  8. Field site selection: getting it right first time around

    PubMed Central

    Malcolm, Colin A; El Sayed, Badria; Babiker, Ahmed; Girod, Romain; Fontenille, Didier; Knols, Bart GJ; Nugud, Abdel Hameed; Benedict, Mark Q

    2009-01-01

    The selection of suitable field sites for integrated control of Anopheles mosquitoes using the sterile insect technique (SIT) requires consideration of the full gamut of factors facing most proposed control strategies, but four criteria identify an ideal site: 1) a single malaria vector, 2) an unstructured, relatively low density target population, 3) isolation of the target population and 4) actual or potential malaria incidence. Such a site can exist in a diverse range of situations or can be created. Two contrasting SIT field sites are examined here: the desert-flanked Dongola Reach of the Nile River in Northern State, Sudan, where malaria is endemic, and the island of La Reunion, where autochthonous malaria is rare but risk is persistent. The single malaria-transmitting vector at both sites is Anopheles arabiensis. In Sudan, the target area is a narrow 500 km corridor stretching from the rocky terrain at the Fourth Cataract - just above the new Merowe Dam, to the northernmost edge of the species range, close to Egypt. Vector distribution and temporal changes in density depend on the Nile level, ambient temperature and human activities. On La Reunion, the An. arabiensis population is coastal, limited and divided into three areas by altitude and exposure to the trade winds on the east coast. Mosquito vectors for other diseases are an issue at both sites, but of primary importance on La Reunion due to the recent chikungunya epidemic. The similarities and differences between these two sites in terms of suitability are discussed in the context of area-wide integrated vector management incorporating the SIT. PMID:19917079

  9. Efficient and scalable Pareto optimization by evolutionary local selection algorithms.

    PubMed

    Menczer, F; Degeratu, M; Street, W N

    2000-01-01

    Local selection is a simple selection scheme in evolutionary computation. Individual fitnesses are accumulated over time and compared to a fixed threshold, rather than to each other, to decide who gets to reproduce. Local selection, coupled with fitness functions stemming from the consumption of finite shared environmental resources, maintains diversity in a way similar to fitness sharing. However, it is more efficient than fitness sharing and lends itself to parallel implementations for distributed tasks. While local selection is not prone to premature convergence, it applies minimal selection pressure to the population. Local selection is, therefore, particularly suited to Pareto optimization or problem classes where diverse solutions must be covered. This paper introduces ELSA, an evolutionary algorithm employing local selection and outlines three experiments in which ELSA is applied to multiobjective problems: a multimodal graph search problem, and two Pareto optimization problems. In all these experiments, ELSA significantly outperforms other well-known evolutionary algorithms. The paper also discusses scalability, parameter dependence, and the potential distributed applications of the algorithm.

  10. Selection and Characterization of the LCROSS Impact Site

    NASA Astrophysics Data System (ADS)

    Bart, Gwendolyn D.; Colaprete, A.

    2008-09-01

    This presentation will discuss characterization of potential LCROSS impact sites and the requirements for impact site selection. LCROSS, the Lunar CRater Observation and Sensing Satellite, will be launched on the same rocket as the Lunar Reconnaissance Orbiter (LRO) next year. The primary LCROSS science goal is to confirm the presence or absence of water ice in a permanently shadowed region on the Moon. To achieve this goal, the LCROSS spacecraft will set the rocket's Centaur Earth departure upper stage (EDUS) on an impact trajectory with the Moon. Following four minutes behind the EDUS, LCROSS will fly through the resulting impact plume, using its 9 instruments (cameras, spectrometers, and photometer) to characterize the plume and identify water. Target selection will be key to the success of this mission. Characterizing the expected terrain within the crater will be difficult because the target impact site is required to be permanently shadowed. Because of lack of high resolution visible imaging at the poles, we use high resolution Earth-based radar data, which can directly observe some parts of the permanently shadowed regions. Once the tools and analysis methods are established, we will be ready to quickly assess new data provided by the instruments on LRO, which will begin taking data 2-3 months prior to the LCROSS impact. The constraints on the impact site selection are: (1) the ejecta plume must be observable by ground-based and orbital observatories. (2) the ejecta must be illuminated by sunlight, since the instruments primarily measure reflected light. (3) the target should be in a region with low roughness, low slopes, and deep regolith cover. (4) the target should be in a region with an observed concentration of increased hydrogen, which could indicate presence of water.

  11. Deciphering the Code for Retroviral Integration Target Site Selection

    PubMed Central

    Santoni, Federico Andrea; Hartley, Oliver; Luban, Jeremy

    2010-01-01

    Upon cell invasion, retroviruses generate a DNA copy of their RNA genome and integrate retroviral cDNA within host chromosomal DNA. Integration occurs throughout the host cell genome, but target site selection is not random. Each subgroup of retrovirus is distinguished from the others by attraction to particular features on chromosomes. Despite extensive efforts to identify host factors that interact with retrovirion components or chromosome features predictive of integration, little is known about how integration sites are selected. We attempted to identify markers predictive of retroviral integration by exploiting Precision-Recall methods for extracting information from highly skewed datasets to derive robust and discriminating measures of association. ChIPSeq datasets for more than 60 factors were compared with 14 retroviral integration datasets. When compared with MLV, PERV or XMRV integration sites, strong association was observed with STAT1, acetylation of H3 and H4 at several positions, and methylation of H2AZ, H3K4, and K9. By combining peaks from ChIPSeq datasets, a supermarker was identified that localized within 2 kB of 75% of MLV proviruses and detected differences in integration preferences among different cell types. The supermarker predicted the likelihood of integration within specific chromosomal regions in a cell-type specific manner, yielding probabilities for integration into proto-oncogene LMO2 identical to experimentally determined values. The supermarker thus identifies chromosomal features highly favored for retroviral integration, provides clues to the mechanism by which retrovirus integration sites are selected, and offers a tool for predicting cell-type specific proto-oncogene activation by retroviruses. PMID:21124862

  12. Strategy Developed for Selecting Optimal Sensors for Monitoring Engine Health

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Sensor indications during rocket engine operation are the primary means of assessing engine performance and health. Effective selection and location of sensors in the operating engine environment enables accurate real-time condition monitoring and rapid engine controller response to mitigate critical fault conditions. These capabilities are crucial to ensure crew safety and mission success. Effective sensor selection also facilitates postflight condition assessment, which contributes to efficient engine maintenance and reduced operating costs. Under the Next Generation Launch Technology program, the NASA Glenn Research Center, in partnership with Rocketdyne Propulsion and Power, has developed a model-based procedure for systematically selecting an optimal sensor suite for assessing rocket engine system health. This optimization process is termed the systematic sensor selection strategy. Engine health management (EHM) systems generally employ multiple diagnostic procedures including data validation, anomaly detection, fault-isolation, and information fusion. The effectiveness of each diagnostic component is affected by the quality, availability, and compatibility of sensor data. Therefore systematic sensor selection is an enabling technology for EHM. Information in three categories is required by the systematic sensor selection strategy. The first category consists of targeted engine fault information; including the description and estimated risk-reduction factor for each identified fault. Risk-reduction factors are used to define and rank the potential merit of timely fault diagnoses. The second category is composed of candidate sensor information; including type, location, and estimated variance in normal operation. The final category includes the definition of fault scenarios characteristic of each targeted engine fault. These scenarios are defined in terms of engine model hardware parameters. Values of these parameters define engine simulations that generate

  13. Rock coasts and seabird breeding sites : a common optimization

    NASA Astrophysics Data System (ADS)

    Marie, Eveillard-Buchoux

    2014-05-01

    The North-West coasts of Europe support a lot of part of Northern hemisphere breeding seabirds. In that context, Scotland has a preponderant place and Brittany has southernmost limit of these species areas, for most of them. Outside the breeding season these species live mainly on the open sea and when they do visit the land to breed, they nest on a specific sites : almost all the time they breed on the rock coasts, often on seacliffs. This specific habitat are defines by geomorphological characteristics which offer special forms of the coast. The forms of rock coasts are originally and different because of several proprieties of geology, of lithology, of structures. Breeding seabird, occupying these sites, reveals, in a new light, the richness of these forms and the originals geographic location of the coastline : seabirds prefer nest in exposed coastline like rock caps, rocky points or islands. Seabirds and rock coasts are research topics in environmental geography since several years. However, these combination studies is a new approach in this field and enlargement in the heritage field allows supplement scientific approach. For example, it show that in most important touristic sites, environmental protection measures focused on landscape, habitat or bird, but much more rarely on rock coasts for these intrinsic values. Indeed, in Brittany or in Scotland, seabirds are often stars species in lot of coastal nature reserves, where they're considered like greater ecological heritage. We could see it in touristic promotion field : bird is everywhere, cliff is mostly kept in the dark, as well in leaflets as in speech visitor's guides - without, for example, as a part of this landscape. In all cases, combination of these two heritages is extremely rare. Yet, this current research illustrates the interest and the issue of development of this comparative approach seabirds / rock coasts for optimization of nature tourism and geotourism.

  14. The method of landing sites selection for Russian lunar lander missions

    NASA Astrophysics Data System (ADS)

    Mitrofanov, Igor; Djachkova, Maya; Litvak, Maxim; Sanin, Anton

    2016-04-01

    Russian space agency is planning to launch two lunar landers in the upcoming years - Luna-Glob (2018) and Luna-Resurs (2021). Instruments installed on board the landers are designed to study volatiles and water ice, lunar exosphere, dust particles and regolith composition. As primary scientific interest is concentrated in the south polar region, the landing sites for both landers will be selected there. Since rugged terrain, conditions of solar illumination at high altitudes and necessity of direct radio communication with the Earth, it is essential to select an optimal landing site for each lander. We present the method of landing sites selection, which is based on geographical information systems (GIS) technologies to perform analysis, based on the criteria of surface suitability for landing, such as slopes, illumination conditions and Earth visibility. In addition, the estimations of hydrogen concentration in regolith based on LEND/LRO data were used to evaluate landing site candidates on possible water ice presence. The method gave us 6 canditates to land. Four of them are located in the impact craters: Simpelius D, Simpelius E, Boguslawsky C, Boussingault, and the other two are located to the north of Schomberger crater and to the north-west of Boguslawsky C crater and associated with probable basin-related materials. The main parameters of these sites will be presented with possible prioritization based on both technical requirements and scientific interest.

  15. Microclimate and nest-site selection in Micronesian Kingfishers

    USGS Publications Warehouse

    Kesler, Dylan C.; Haig, Susan M.

    2005-01-01

    We studied the relationship between microclimate and nest-site selection in the Pohnpei Micronesian Kingfisher (Todiramphus cinnamominus reichenbachii) which excavates nest cavities from the mudlike nest structures of arboreal termites (Nasutitermes sp.) or termitaria. Mean daily high temperatures at termitaria were cooler and daily low temperatures were warmer than at random sites in the forest. Results also indicate that termitaria provided insulation from temperature extremes, and that temperatures inside termitaria were within the thermoneutral zone of Micronesian Kingfishers more often than those outside. No differences were identified in temperatures at sites where nest termitaria and nonnest termitaria occurred or among the insulation properties of used and unused termitaria. These results suggest that although termitaria provide insulation from thermal extremes and a metabolically less stressful microclimate, king-fishers did not select from among available termitaria based on their thermal properties. Our findings are relevant to conservation efforts for the critically endangered Guam Micronesian Kingfisher (T. c. cinnamominus) which is extinct in the wild and exists only as a captive population. Captive breeding facilities should provide aviaries with daily ambient temperatures ranging from 22.06 A?C to 28.05 A?C to reduce microclimate-associated metabolic stress and to replicate microclimates used by wild Micronesian Kingfishers.

  16. Site selection for MSFC operational tests of solar heating and cooling systems

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The criteria, methodology, and sequence aspects of the site selection process are presented. This report organized the logical thought process that should be applied to the site selection process, but final decisions are highly selective.

  17. Optimizing Ligand Efficiency of Selective Androgen Receptor Modulators (SARMs).

    PubMed

    Handlon, Anthony L; Schaller, Lee T; Leesnitzer, Lisa M; Merrihew, Raymond V; Poole, Chuck; Ulrich, John C; Wilson, Joseph W; Cadilla, Rodolfo; Turnbull, Philip

    2016-01-14

    A series of selective androgen receptor modulators (SARMs) containing the 1-(trifluoromethyl)benzyl alcohol core have been optimized for androgen receptor (AR) potency and drug-like properties. We have taken advantage of the lipophilic ligand efficiency (LLE) parameter as a guide to interpret the effect of structural changes on AR activity. Over the course of optimization efforts the LLE increased over 3 log units leading to a SARM 43 with nanomolar potency, good aqueous kinetic solubility (>700 μM), and high oral bioavailability in rats (83%).

  18. Optimizing Ligand Efficiency of Selective Androgen Receptor Modulators (SARMs)

    PubMed Central

    2015-01-01

    A series of selective androgen receptor modulators (SARMs) containing the 1-(trifluoromethyl)benzyl alcohol core have been optimized for androgen receptor (AR) potency and drug-like properties. We have taken advantage of the lipophilic ligand efficiency (LLE) parameter as a guide to interpret the effect of structural changes on AR activity. Over the course of optimization efforts the LLE increased over 3 log units leading to a SARM 43 with nanomolar potency, good aqueous kinetic solubility (>700 μM), and high oral bioavailability in rats (83%). PMID:26819671

  19. Optimized LOWESS normalization parameter selection for DNA microarray data

    PubMed Central

    Berger, John A; Hautaniemi, Sampsa; Järvinen, Anna-Kaarina; Edgren, Henrik; Mitra, Sanjit K; Astola, Jaakko

    2004-01-01

    Background Microarray data normalization is an important step for obtaining data that are reliable and usable for subsequent analysis. One of the most commonly utilized normalization techniques is the locally weighted scatterplot smoothing (LOWESS) algorithm. However, a much overlooked concern with the LOWESS normalization strategy deals with choosing the appropriate parameters. Parameters are usually chosen arbitrarily, which may reduce the efficiency of the normalization and result in non-optimally normalized data. Thus, there is a need to explore LOWESS parameter selection in greater detail. Results and discussion In this work, we discuss how to choose parameters for the LOWESS method. Moreover, we present an optimization approach for obtaining the fraction of data points utilized in the local regression and analyze results for local print-tip normalization. The optimization procedure determines the bandwidth parameter for the local regression by minimizing a cost function that represents the mean-squared difference between the LOWESS estimates and the normalization reference level. We demonstrate the utility of the systematic parameter selection using two publicly available data sets. The first data set consists of three self versus self hybridizations, which allow for a quantitative study of the optimization method. The second data set contains a collection of DNA microarray data from a breast cancer study utilizing four breast cancer cell lines. Our results show that different parameter choices for the bandwidth window yield dramatically different calibration results in both studies. Conclusions Results derived from the self versus self experiment indicate that the proposed optimization approach is a plausible solution for estimating the LOWESS parameters, while results from the breast cancer experiment show that the optimization procedure is readily applicable to real-life microarray data normalization. In summary, the systematic approach to obtain critical

  20. Site selection for manned Mars landings: A geological perspective

    NASA Technical Reports Server (NTRS)

    Spudis, Paul D.

    1986-01-01

    Issues relating to the selection of initial landing sites for manned Mars missions are discussed from a geological viewpoint. The two prime objectives for initial manned exploration should be the youngest unambiguous lava flows (to tie down the late end of the cratering history curve for Mars) and old highland crust, which is best sampled and studied through the use of large impact basins as natural, planetary drill-holes. Exploration of these two sites will provide data on Martian chronology, volcanism, impact processes and gross chemical structure that will enable a first-order global synthesis through integration of these results with the global remote-sensing data already in hand from Viking and that to be provided by the Mars Observer Mission.

  1. ExoMars 2018 Landing Site Selection Process

    NASA Astrophysics Data System (ADS)

    Vago, Jorge L.; Kminek, Gerhard; Rodionov, Daniel

    The ExoMars 2018 mission will include two science elements: a Rover and a Surface Platform. The ExoMars Rover will carry a comprehensive suite of instruments dedicated to geology and exobiology research named after Louis Pasteur. The Rover will be able to travel several kilometres searching for traces of past and present signs of life. It will do this by collecting and analysing samples from outcrops, and from the subsurface—down to 2-m depth. The very powerful combination of mobility with the ability to access locations where organic molecules can be well preserved is unique to this mission. After the Rover will have egressed, the ExoMars Surface Platform will begin its science mission to study the surface environment at the landing location. This talk will describe the landing site selection process and introduce the scientific, planetary protection, and engineering requirements that candidate landing sites must comply with in order to be considered for the mission.

  2. Selection of the InSight Landing Site

    NASA Astrophysics Data System (ADS)

    Golombek, M.; Kipp, D.; Warner, N.; Daubar, I. J.; Fergason, R.; Kirk, R. L.; Beyer, R.; Huertas, A.; Piqueux, S.; Putzig, N. E.; Campbell, B. A.; Morgan, G. A.; Charalambous, C.; Pike, W. T.; Gwinner, K.; Calef, F.; Kass, D.; Mischna, M.; Ashley, J.; Bloom, C.; Wigton, N.; Hare, T.; Schwartz, C.; Gengl, H.; Redmond, L.; Trautman, M.; Sweeney, J.; Grima, C.; Smith, I. B.; Sklyanskiy, E.; Lisano, M.; Benardini, J.; Smrekar, S.; Lognonné, P.; Banerdt, W. B.

    2016-12-01

    The selection of the Discovery Program InSight landing site took over four years from initial identification of possible areas that met engineering constraints, to downselection via targeted data from orbiters (especially Mars Reconnaissance Orbiter (MRO) Context Camera (CTX) and High-Resolution Imaging Science Experiment (HiRISE) images), to selection and certification via sophisticated entry, descent and landing (EDL) simulations. Constraints on elevation ( {≤}{-}2.5 km for sufficient atmosphere to slow the lander), latitude (initially 15°S-5°N and later 3°N-5°N for solar power and thermal management of the spacecraft), ellipse size (130 km by 27 km from ballistic entry and descent), and a load bearing surface without thick deposits of dust, severely limited acceptable areas to western Elysium Planitia. Within this area, 16 prospective ellipses were identified, which lie ˜600 km north of the Mars Science Laboratory (MSL) rover. Mapping of terrains in rapidly acquired CTX images identified especially benign smooth terrain and led to the downselection to four northern ellipses. Acquisition of nearly continuous HiRISE, additional Thermal Emission Imaging System (THEMIS), and High Resolution Stereo Camera (HRSC) images, along with radar data confirmed that ellipse E9 met all landing site constraints: with slopes <15° at 84 m and 2 m length scales for radar tracking and touchdown stability, low rock abundance (<10 %) to avoid impact and spacecraft tip over, instrument deployment constraints, which included identical slope and rock abundance constraints, a radar reflective and load bearing surface, and a fragmented regolith ˜5 m thick for full penetration of the heat flow probe. Unlike other Mars landers, science objectives did not directly influence landing site selection.

  3. Competitor phenology as a social cue in breeding site selection.

    PubMed

    Samplonius, Jelmer M; Both, Christiaan

    2017-05-01

    Predicting habitat quality is a major challenge for animals selecting a breeding patch, because it affects reproductive success. Breeding site selection may be based on previous experience, or on social information from the density and success of competitors with an earlier phenology. Variation in animal breeding phenology is often correlated with variation in habitat quality. Generally, animals breed earlier in high-quality habitats that allow them to reach a nutritional threshold required for breeding earlier or avoid nest predation. In addition, habitat quality may affect phenological overlap between species and thereby interspecific competition. Therefore, we hypothesized that competitor breeding phenology can be used as social cue by settling migrants to locate high-quality breeding sites. To test this hypothesis, we experimentally advanced and delayed hatching phenology of two resident tit species on the level of study plots and studied male and female settlement patterns of migratory pied flycatchers Ficedula hypoleuca. The manipulations were assigned at random in two consecutive years, and treatments were swapped between years in sites that were used in both years. In both years, males settled in equal numbers across treatments, but later arriving females avoided pairing with males in delayed phenology plots. Moreover, male pairing probability declined strongly with arrival date on the breeding grounds. Our results demonstrate that competitor phenology may be used to assess habitat quality by settling migrants, but we cannot pinpoint the exact mechanism (e.g. resource quality, predation pressure or competition) that has given rise to this pattern. In addition, we show that opposing selection pressures for arrival timing may give rise to different social information availabilities between sexes. We discuss our findings in the context of climate warming, social information use and the evolution of protandry in migratory animals.

  4. Using Geoscience and Geostatistics to Optimize Groundwater Monitoring Networks at the Savannah River Site

    SciTech Connect

    Tuckfield, R.C.

    2001-03-22

    A team of scientists, engineers, and statisticians was assembled to review the operation efficiency of groundwater monitoring networks at US Department of Energy Savannah River Site (SRS). Subsequent to a feasibility study, this team selected and conducted an analysis of the A/M area groundwater monitoring well network. The purpose was to optimize the number of groundwater wells requisite for monitoring the plumes of the principal constituent of concern, viz., trichloroethylene (TCE). The project gathered technical expertise from the Savannah River Technology Center (SRTC), the Environmental Restoration Division (ERD), and the Environmental Protection Department (EPD) of SRS.

  5. A selection system for identifying accessible sites in target RNAs.

    PubMed

    Pan, W H; Devlin, H F; Kelley, C; Isom, H C; Clawson, G A

    2001-04-01

    Although ribozymes offer tremendous potential for posttranscriptionally controlling expression of targeted genes, their utility is often limited by the accessibility of the targeted regions within the RNA transcripts. Here we describe a method that identifies RNA regions that are accessible to oligonucleotides. Based on this selection protocol, we show that construction of hammerhead ribozymes targeted to the identified regions results in catalytic activities that are consistently and substantially greater than those of ribozymes designed on the basis of computer modeling. Identification of accessible sites should also be widely applicable to design of antisense oligonucleotides and DNAzymes.

  6. Systematic optimization model and algorithm for binding sequence selection in computational enzyme design

    PubMed Central

    Huang, Xiaoqiang; Han, Kehang; Zhu, Yushan

    2013-01-01

    A systematic optimization model for binding sequence selection in computational enzyme design was developed based on the transition state theory of enzyme catalysis and graph-theoretical modeling. The saddle point on the free energy surface of the reaction system was represented by catalytic geometrical constraints, and the binding energy between the active site and transition state was minimized to reduce the activation energy barrier. The resulting hyperscale combinatorial optimization problem was tackled using a novel heuristic global optimization algorithm, which was inspired and tested by the protein core sequence selection problem. The sequence recapitulation tests on native active sites for two enzyme catalyzed hydrolytic reactions were applied to evaluate the predictive power of the design methodology. The results of the calculation show that most of the native binding sites can be successfully identified if the catalytic geometrical constraints and the structural motifs of the substrate are taken into account. Reliably predicting active site sequences may have significant implications for the creation of novel enzymes that are capable of catalyzing targeted chemical reactions. PMID:23649589

  7. Systematic optimization model and algorithm for binding sequence selection in computational enzyme design.

    PubMed

    Huang, Xiaoqiang; Han, Kehang; Zhu, Yushan

    2013-07-01

    A systematic optimization model for binding sequence selection in computational enzyme design was developed based on the transition state theory of enzyme catalysis and graph-theoretical modeling. The saddle point on the free energy surface of the reaction system was represented by catalytic geometrical constraints, and the binding energy between the active site and transition state was minimized to reduce the activation energy barrier. The resulting hyperscale combinatorial optimization problem was tackled using a novel heuristic global optimization algorithm, which was inspired and tested by the protein core sequence selection problem. The sequence recapitulation tests on native active sites for two enzyme catalyzed hydrolytic reactions were applied to evaluate the predictive power of the design methodology. The results of the calculation show that most of the native binding sites can be successfully identified if the catalytic geometrical constraints and the structural motifs of the substrate are taken into account. Reliably predicting active site sequences may have significant implications for the creation of novel enzymes that are capable of catalyzing targeted chemical reactions.

  8. Implications of high-spatial-resolution thermal infrared (Termoskan) data for Mars landing site selection

    NASA Technical Reports Server (NTRS)

    Betts, Bruce H.

    1994-01-01

    Thermal infrared observations of Mars from spacecraft provide physical information about the upper thermal skin depth of the surface, which is on the order of a few centimeters in depth and thus very significant for lander site selection. The Termoskan instrument onboard the Soviet Phobos '88 spacecraft acquired the highest spatial-resolution thermal infrared data obtained for Mars, ranging in resolution from 300 m to 3 km per pixel. It simultaneously obtained broadband reflected solar flux data. Although the 6 deg N - 30 deg S Termoskan coverage only slightly overlaps the nominal Mars Pathfinder target range, the implications of Termoskan data for that overlap region and the extrapolations that can be made to other regions give important clues for optimal landing site selection.

  9. Mars Exploration Program 2007 Phoenix landing site selection and characteristics

    USGS Publications Warehouse

    Arvidson, R.; Adams, D.; Bonfiglio, G.; Christensen, P.; Cull, S.; Golombek, M.; Guinn, J.; Guinness, E.; Heet, T.; Kirk, R.; Knudson, A.; Malin, M.; Mellon, M.; McEwen, A.; Mushkin, A.; Parker, T.; Seelos, F.; Seelos, K.; Smith, P.; Spencer, D.; Stein, T.; Tamppari, L.

    2009-01-01

    To ensure a successful touchdown and subsequent surface operations, the Mars Exploration Program 2007 Phoenix Lander must land within 65?? to 72?? north latitude, at an elevation less than -3.5 km. The landing site must have relatively low wind velocities and rock and slope distributions similar to or more benign than those found at the Viking Lander 2 site. Also, the site must have a soil cover of at least several centimeters over ice or icy soil to meet science objectives of evaluating the environmental and habitability implications of past and current near-polar environments. The most challenging aspects of site selection were the extensive rock fields associated with crater rims and ejecta deposits and the centers of polygons associated with patterned ground. An extensive acquisition campaign of Odyssey Thermal Emission Imaging Spectrometer predawn thermal IR images, together with ???0.31 m/pixel Mars Reconnaissance Orbiter High Resolution Imaging Science Experiment images was implemented to find regions with acceptable rock populations and to support Monte Carlo landing simulations. The chosen site is located at 68.16?? north latitude, 233.35?? east longitude (areocentric), within a ???50 km wide (N-S) by ???300 km long (E-W) valley of relatively rock-free plains. Surfaces within the eastern portion of the valley are differentially eroded ejecta deposits from the relatively recent ???10-km-wide Heimdall crater and have fewer rocks than plains on the western portion of the valley. All surfaces exhibit polygonal ground, which is associated with fracture of icy soils, and are predicted to have only several centimeters of poorly sorted basaltic sand and dust over icy soil deposits. Copyright 2008 by the American Geophysical Union.

  10. Rocky Mountain snowpack chemistry at selected sites for 2001

    USGS Publications Warehouse

    Ingersoll, George P.; Mast, M. Alisa; Clow, David W.; Nanus, Leora; Campbell, Donald H.; Handran, Heather

    2003-01-01

    Because regional-scale atmospheric deposition data in the Rocky Mountains are sparse, a program was designed by the U.S. Geological Survey, in cooperation with the National Park Service, U.S. Department of Agriculture Forest Service, and other agencies, to more thoroughly determine the chemical composition of precipitation and to identify sources of atmospherically deposited contaminants in a network of high-elevation sites. Samples of seasonal snowpacks at 57 geographically distributed sites, in a regional network from New Mexico to Montana, were collected and analyzed for major ions (including ammonium, nitrate, and sulfate), alkalinity, and dissolved organic carbon during 2001. Sites selected in this report have been sampled annually since 1993, enabling identification of increases or decreases in chemical concentrations from year to year. Spatial patterns in snowpack-chemical data for concentrations of ammonium, nitrate, and sulfate indicate that concentrations of these acid precursors in less developed areas of the region are lower than concentrations in the heavily developed areas. Results for the 2001 snowpack-chemistry analyses, however, indicate increases in concentrations of ammonium and nitrate in particular at sites where past concentrations typically were lower. Since 1993, concentrations of nitrate and sulfate were highest from snowpack samples in northern Colorado that were collected from sites adjacent to the Denver metropolitan area to the east and the coal-fired powerplants to the west. In 2001, relatively high concentrations of nitrate (12.3 to 23.0 microequivalents per liter (?eq/L) and sulfate (7.7 to 12.5 ?eq/L) were detected in Montana and Wyoming. Ammonium concentrations were highest in north-central Colorado (14.5 to 16.9 ?eq/L) and southwestern Montana (12.8 to 14.2 ?eq/L).

  11. Parameter Optimization for Selected Correlation Analysis of Intracranial Pathophysiology

    PubMed Central

    Faltermeier, Rupert; Proescholdt, Martin A.; Bele, Sylvia; Brawanski, Alexander

    2015-01-01

    Recently we proposed a mathematical tool set, called selected correlation analysis, that reliably detects positive and negative correlations between arterial blood pressure (ABP) and intracranial pressure (ICP). Such correlations are associated with severe impairment of the cerebral autoregulation and intracranial compliance, as predicted by a mathematical model. The time resolved selected correlation analysis is based on a windowing technique combined with Fourier-based coherence calculations and therefore depends on several parameters. For real time application of this method at an ICU it is inevitable to adjust this mathematical tool for high sensitivity and distinct reliability. In this study, we will introduce a method to optimize the parameters of the selected correlation analysis by correlating an index, called selected correlation positive (SCP), with the outcome of the patients represented by the Glasgow Outcome Scale (GOS). For that purpose, the data of twenty-five patients were used to calculate the SCP value for each patient and multitude of feasible parameter sets of the selected correlation analysis. It could be shown that an optimized set of parameters is able to improve the sensitivity of the method by a factor greater than four in comparison to our first analyses. PMID:26693250

  12. Optimization of the selective frequency damping parameters using model reduction

    NASA Astrophysics Data System (ADS)

    Cunha, Guilherme; Passaggia, Pierre-Yves; Lazareff, Marc

    2015-09-01

    In the present work, an optimization methodology to compute the best control parameters, χ and Δ, for the selective frequency damping method is presented. The optimization does not suppose any a priori knowledge of the flow physics, neither of the underlying numerical methods, and is especially suited for simulations requiring large quantity of grid elements and processors. It allows for obtaining an optimal convergence rate to a steady state of the damped Navier-Stokes system. This is achieved using the Dynamic Mode Decomposition, which is a snapshot-based method, to estimate the eigenvalues associated with global unstable dynamics. Validations test cases are presented for the numerical configurations of a laminar flow past a 2D cylinder, a separated boundary-layer over a shallow bump, and a 3D turbulent stratified-Poiseuille flow.

  13. Optimization Review: Carson River Mercury Superfund Site, Carson City, Nevada

    EPA Pesticide Factsheets

    The Carson River Mercury Site (CRMS) (Figure 1) is located in northwest Nevada and was designated a Superfund site in 1990 because of elevated mercury concentrations observed in surface water, sediments and biota inhabiting the site.

  14. Optimization Review, Black Butte Mine Superfund Site, Lane County, Oregon

    EPA Pesticide Factsheets

    The BBM Superfund Site (the site) is located in Lane County, Oregon, approximately 35 miles southeast of Eugene and approximately 10 miles upstream from the Cottage Grove Reservoir (CGR). Mercury mining and processing operations were active at the site...

  15. Salt Effect Accelerates Site-Selective Cysteine Bioconjugation

    PubMed Central

    2016-01-01

    Highly efficient and selective chemical reactions are desired. For small molecule chemistry, the reaction rate can be varied by changing the concentration, temperature, and solvent used. In contrast for large biomolecules, the reaction rate is difficult to modify by adjusting these variables because stringent biocompatible reaction conditions are required. Here we show that adding salts can change the rate constant over 4 orders of magnitude for an arylation bioconjugation reaction between a cysteine residue within a four-residue sequence (π-clamp) and a perfluoroaryl electrophile. Biocompatible ammonium sulfate significantly enhances the reaction rate without influencing the site-specificity of π-clamp mediated arylation, enabling the fast synthesis of two site-specific antibody–drug conjugates that selectively kill HER2-positive breast cancer cells. Computational and structure–reactivity studies indicate that salts may tune the reaction rate through modulating the interactions between the π-clamp hydrophobic side chains and the electrophile. On the basis of this understanding, the salt effect is extended to other bioconjugation chemistry, and a new regioselective alkylation reaction at π-clamp cysteine is developed. PMID:27725962

  16. Site Selection for Ground Based Free Electron Laser Technology Integration Experiment (GBFEL-TIE), Volume 3: Preferred Site Evaluation

    DTIC Science & Technology

    1987-04-01

    established that the GBFEL-TIE could be accomplished at any of the three candidate sites. However, based on differences identified during site investigations...construction and operation of the GBFEL-TIE, including environmental mitigation costs, differed only slightly among the three sites, with the Orogrande site...the differences in the findings that would affect site selection, and established a relative ranking of the three sites under consideration. The

  17. 40 CFR 761.247 - Sample site selection for pipe segment removal.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Sample site selection for pipe segment... Natural Gas Pipeline: Selecting Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.247 Sample site selection for pipe segment removal. (a) General. (1) Select the...

  18. 40 CFR 761.247 - Sample site selection for pipe segment removal.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Sample site selection for pipe segment... Natural Gas Pipeline: Selecting Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.247 Sample site selection for pipe segment removal. (a) General. (1) Select the...

  19. State-Selective Excitation of Quantum Systems via Geometrical Optimization.

    PubMed

    Chang, Bo Y; Shin, Seokmin; Sola, Ignacio R

    2015-09-08

    We lay out the foundations of a general method of quantum control via geometrical optimization. We apply the method to state-selective population transfer using ultrashort transform-limited pulses between manifolds of levels that may represent, e.g., state-selective transitions in molecules. Assuming that certain states can be prepared, we develop three implementations: (i) preoptimization, which implies engineering the initial state within the ground manifold or electronic state before the pulse is applied; (ii) postoptimization, which implies engineering the final state within the excited manifold or target electronic state, after the pulse; and (iii) double-time optimization, which uses both types of time-ordered manipulations. We apply the schemes to two important dynamical problems: To prepare arbitrary vibrational superposition states on the target electronic state and to select weakly coupled vibrational states. Whereas full population inversion between the electronic states only requires control at initial time in all of the ground vibrational levels, only very specific superposition states can be prepared with high fidelity by either pre- or postoptimization mechanisms. Full state-selective population inversion requires manipulating the vibrational coherences in the ground electronic state before the optical pulse is applied and in the excited electronic state afterward, but not during all times.

  20. Greater Green River basin well-site selection

    SciTech Connect

    Frohne, K.H.; Boswell, R.

    1993-12-31

    Recent estimates of the natural gas resources of Cretaceous low-permeability reservoirs of the Greater Green River basin indicate that as much as 5000 trillion cubic feet (Tcf) of gas may be in place (Law and others 1989). Of this total, Law and others (1989) attributed approximately 80 percent to the Upper Cretaceous Mesaverde Group and Lewis Shale. Unfortunately, present economic conditions render the drilling of many vertical wells unprofitable. Consequently, a three-well demonstration program, jointly sponsored by the US DOE/METC and the Gas Research Institute, was designed to test the profitability of this resource using state-of-the-art directional drilling and completion techniques. DOE/METC studied the geologic and engineering characteristics of ``tight`` gas reservoirs in the eastern portion of the Greater Green River basin in order to identify specific locations that displayed the greatest potential for a successful field demonstration. This area encompasses the Rocks Springs Uplift, Wamsutter Arch, and the Washakie and Red Desert (or Great Divide) basins of southwestern Wyoming. The work was divided into three phases. Phase 1 consisted of a regional geologic reconnaissance of 14 gas-producing areas encompassing 98 separate gas fields. In Phase 2, the top four areas were analyzed in greater detail, and the area containing the most favorable conditions was selected for the identification of specific test sites. In Phase 3, target horizons were selected for each project area, and specific placement locations were selected and prioritized.

  1. Optimization of topical gels with betamethasone dipropionate: selection of gel forming and optimal cosolvent system.

    PubMed

    Băiţan, Mariana; Lionte, Mihaela; Moisuc, Lăcrămioara; Gafiţanu, Eliza

    2011-01-01

    The purpose of these studies was to develop a 0.05% betamethasone gel characterized by physical-chemical stability and good release properties. The preliminary studies were designed to select the gel-forming agents and the excipients compatible with betamethasone dipropionate. In order to formulate a clear gel without particles of drug substances in suspension, a solvent system for the drug substance was selected. The content of drug substance released, the rheological and in vitro release tests were the tools used for the optimal formulation selection. A stable carbomer gel was obtained by solubilization of betamethasone dipropionate in a vehicle composed by 40% PEG 400, 10% ethanol and 5% Transcutol.

  2. An R-D optimized transcoding resilient motion vector selection

    NASA Astrophysics Data System (ADS)

    Aminlou, Alireza; Semsarzadeh, Mehdi; Fatemi, Omid

    2014-12-01

    Selection of motion vector (MV) has a significant impact on the quality of an encoded, and particularly a transcoded video, in terms of rate-distortion (R-D) performance. The conventional motion estimation process, in most existing video encoders, ignores the rate of residuals by utilizing rate and distortion of motion compensation step. This approach implies that the selected MV depends on the quantization parameter. Hence, the same MV that has been selected for high bit rate compression may not be suitable for low bit rate ones when transcoding the video with motion information reuse technique, resulting in R-D performance degradation. In this paper, we propose an R-D optimized motion selection criterion that takes into account the effect of residual rate in MV selection process. Based on the proposed criterion, a new two-piece Lagrange multiplier selection is introduced for motion estimation process. Analytical evaluations indicate that our proposed scheme results in MVs that are less sensitive to changes in bit rate or quantization parameter. As a result, MVs in the encoded bitstream may be used even after the encoded sequence has been transcoded to a lower bit rate one using re-quantization. Simulation results indicate that the proposed technique improves the quality performance of coding and transcoding without any computational overhead.

  3. Remote Borehole Strainmeter Sites: Power system optimization improves data quality and increases equipment uptime

    NASA Astrophysics Data System (ADS)

    Pyatt, C.; Van Boskirk, E.; Gallaher, W.; Hodgkinson, K. M.; Henderson, D. B.; Gottlieb, M. H.; Johnson, W.; Fox, O.; Mencin, D.; Mattioli, G.

    2012-12-01

    The Earthscope Plate Boundary Observatory (PBO) Borehole strainmeter network consists of 74 sites, spanning the west coast of North America from Anza, California to Vancouver Island, British Columbia. Several instruments are installed at each site (including Gladwin Tensor Strainmeter, 3-component geophone, barometer, and rain gauge), with associated data storage and communications equipment. Selected sites also are co-located with high-precision GPS, tiltmeter, pore pressure sensor and metpack. The peak load for a site with VSAT communications is approximately 65W. Most sites are AC powered with battery backup systems. 21 sites are located in remote areas where AC power is unavailable; of these, 18 use solar panels and batteries as the primary power source. During O&M phase of PBO, two issues have brought the borehole solar sites into focus. First, most solar sites cannot continuously operate throughout the winter months because of inclement weather and local topography that blocks the solar array, which results in data loss. Second, high frequency noise is introduced into the instrument data stream by the solar charging system. Reducing noise levels at higher frequencies would decrease the detection threshold for short term transients, such as aseismic creep events, thus allowing researchers to leverage the overlap between simultaneous seismometer and strainmeter observations. Several improvements have been made to optimize the power system as well as decrease noise. TriStar TS-MPPT-60 solar controllers have been installed, which optimize solar flux by tracking and responding to the solar array maximum power point. The battery charge algorithm is designed to provide gains of up to 15% efficiency during winter months. In addition, the new solar controllers have been engineered to limit noise, and also feature remote network interfaces and data logging capability. For those sites where topography impacts the function of the solar power system, methanol fuel cells

  4. Field of view selection for optimal airborne imaging sensor performance

    NASA Astrophysics Data System (ADS)

    Goss, Tristan M.; Barnard, P. Werner; Fildis, Halidun; Erbudak, Mustafa; Senger, Tolga; Alpman, Mehmet E.

    2014-05-01

    The choice of the Field of View (FOV) of imaging sensors used in airborne targeting applications has major impact on the overall performance of the system. Conducting a market survey from published data on sensors used in stabilized airborne targeting systems shows a trend of ever narrowing FOVs housed in smaller and lighter volumes. This approach promotes the ever increasing geometric resolution provided by narrower FOVs, while it seemingly ignores the influences the FOV selection has on the sensor's sensitivity, the effects of diffraction, the influences of sight line jitter and collectively the overall system performance. This paper presents a trade-off methodology to select the optimal FOV for an imaging sensor that is limited in aperture diameter by mechanical constraints (such as space/volume available and window size) by balancing the influences FOV has on sensitivity and resolution and thereby optimizing the system's performance. The methodology may be applied to staring array based imaging sensors across all wavebands from visible/day cameras through to long wave infrared thermal imagers. Some examples of sensor analysis applying the trade-off methodology are given that highlights the performance advantages that can be gained by maximizing the aperture diameters and choosing the optimal FOV for an imaging sensor used in airborne targeting applications.

  5. Measurement of volatile organic chemicals at selected sites in California

    NASA Technical Reports Server (NTRS)

    Singh, Hanwant B.; Salas, L.; Viezee, W.; Sitton, B.; Ferek, R.

    1992-01-01

    Urban air concentrations of 24 selected volatile organic chemicals that may be potentially hazardous to human health and environment were measured during field experiments conducted at two California locations, at Houston, and at Denver. Chemicals measured included chlorofluorocarbons, halomethanes, haloethanes, halopropanes, chloroethylenes, and aromatic hydrocarbons. With emphasis on California sites, data from these studies are analyzed and interpreted with respect to variabilities in ambient air concentrations, diurnal changes, relation to prevailing meteorology, sources and trends. Except in a few instances, mean concentrations are typically between 0 and 5 ppb. Significant variabilities in atmospheric concentrations associated with intense sources and adverse meteorological conditions are shown to exist. In addition to short-term variability, there is evidence of systematic diurnal and seasonal trends. In some instances it is possible to detect declining trends resulting from the effectiveness of control strategies.

  6. The Application of Computer-Aided Discovery to Spacecraft Site Selection

    NASA Astrophysics Data System (ADS)

    Pankratius, V.; Blair, D. M.; Gowanlock, M.; Herring, T.

    2015-12-01

    The selection of landing and exploration sites for interplanetary robotic or human missions is a complex task. Historically it has been labor-intensive, with large groups of scientists manually interpreting a planetary surface across a variety of datasets to identify potential sites based on science and engineering constraints. This search process can be lengthy, and excellent sites may get overlooked when the aggregate value of site selection criteria is non-obvious or non-intuitive. As planetary data collection leads to Big Data repositories and a growing set of selection criteria, scientists will face a combinatorial search space explosion that requires scalable, automated assistance. We are currently exploring more general computer-aided discovery techniques in the context of planetary surface deformation phenomena that can lend themselves to application in the landing site search problem. In particular, we are developing a general software framework that addresses key difficulties: characterizing a given phenomenon or site based on data gathered from multiple instruments (e.g. radar interferometry, gravity, thermal maps, or GPS time series), and examining a variety of possible workflows whose individual configurations are optimized to isolate different features. The framework allows algorithmic pipelines and hypothesized models to be perturbed or permuted automatically within well-defined bounds established by the scientist. For example, even simple choices for outlier and noise handling or data interpolation can drastically affect the detectability of certain features. These techniques aim to automate repetitive tasks that scientists routinely perform in exploratory analysis, and make them more efficient and scalable by executing them in parallel in the cloud. We also explore ways in which machine learning can be combined with human feedback to prune the search space and converge to desirable results. Acknowledgements: We acknowledge support from NASA AIST

  7. Optimization Review, Peck Iron and Metal Superfund Site, Portsmouth, Virginia

    EPA Pesticide Factsheets

    The Peck Iron and Metal Superfund Site is a 33-acre property located in Norfolk County, Portsmouth, Virginia. PIM (Figure 1) is the site of a former scrap metal storage and recycling facility that began operation in the 1940s.

  8. Geospatial optimization of siting large-scale solar projects

    USGS Publications Warehouse

    Macknick, Jordan; Quinby, Ted; Caulfield, Emmet; Gerritsen, Margot; Diffendorfer, James E.; Haines, Seth S.

    2014-01-01

    guidelines by being user-driven, transparent, interactive, capable of incorporating multiple criteria, and flexible. This work provides the foundation for a dynamic siting assistance tool that can greatly facilitate siting decisions among multiple stakeholders.

  9. Helium mining on the Moon: Site selection and evaluation

    NASA Technical Reports Server (NTRS)

    Cameron, Eugene N.

    1992-01-01

    The feasibility of recovering helium (He) from the Moon as a source of fusion energy on Earth is currently being studied at the University of Wisconsin. Part of this study is selection and evaluation of potential sites for lunar He mining. Selection and evaluation of potential mining sites are based on four salient findings by various investigators of lunar samples: (1) Regoliths from areas underlain by highland materials contain less than 20 wppm He; (2) Certain maria regoliths contain less than 20 wppm He, but other contain 25 to 49 wppm; (3) The He content of a mare regolith is a function of its composition; regoliths rich in Ti are relatively rich in He; and (4) He is concentrated in the less than 100-micron size fractions of regoliths. The first three findings suggest that maria are the most promising mining sites, specifically, those that have high-Ti regoliths. Information on the regional distribution and extent of high-Ti regoliths comes mainly from two sources: direct sampling by various Apollo and Luna missions, and remote sensing by gamma-ray spectroscopy and Earth-based measurements of lunar spectral reflectance. Sampling provides essential control on calibration and interpretation of data from remote sensing. These data indicate that Mare Tranquillitatis is the principal area of high-Ti regolith of the eastern nearside, but large areas of high-Ti regolith are indicated in the Imbrium and Procellarum regions. Recovery of significant amounts of He-3 will require mining billions of tonnes of regolith. Large individual areas suitable for mining must therefore be delineated. The concentration of He in the finer size fractions and considerations of ease of mining mean that mining areas must be as free as possible of sizable craters and blocks of rock. Pending additional lunar missions, information regarding these features must be obtained from lunar photographs, photogeologic maps, and radar surveys. The present study is decidedly preliminary; available

  10. Evaluation of different approaches for identifying optimal sites to predict mean hillslope soil moisture content

    NASA Astrophysics Data System (ADS)

    Liao, Kaihua; Zhou, Zhiwen; Lai, Xiaoming; Zhu, Qing; Feng, Huihui

    2017-04-01

    -means method (EFsTheta-PCA). Overall, TS required only one site, but its accuracy was limited. The best K-means method required <8 sites and yielded high accuracy, but extra soil and terrain information is necessary when using this method. The stratified sampling strategy can only be used if no pre-knowledge about soil moisture variation is available. This information will help in selecting the optimal methods for estimation the area mean soil moisture.

  11. Initial basalt target site selection evaluation for the Mars penetrator drop test

    NASA Technical Reports Server (NTRS)

    Bunch, T. E.; Quaide, W. L.; Polkowski, G.

    1976-01-01

    Potential basalt target sites for an air drop penetrator test were described and the criteria involved in site selection were discussed. A summary of the background field geology and recommendations for optimum sites are also presented.

  12. 40 CFR 761.250 - Sample site selection for pipeline section abandonment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Sample site selection for pipeline... Disposal of Natural Gas Pipeline: Selecting Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.250 Sample site selection for pipeline section abandonment. This...

  13. 40 CFR 761.250 - Sample site selection for pipeline section abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Sample site selection for pipeline... Disposal of Natural Gas Pipeline: Selecting Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.250 Sample site selection for pipeline section abandonment. This...

  14. 40 CFR 761.250 - Sample site selection for pipeline section abandonment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Sample site selection for pipeline... Disposal of Natural Gas Pipeline: Selecting Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.250 Sample site selection for pipeline section abandonment. This...

  15. Fuzzy multicriteria disposal method and site selection for municipal solid waste

    SciTech Connect

    Ekmekcioglu, Mehmet; Kaya, Tolga; Kahraman, Cengiz

    2010-08-15

    The use of fuzzy multiple criteria analysis (MCA) in solid waste management has the advantage of rendering subjective and implicit decision making more objective and analytical, with its ability to accommodate both quantitative and qualitative data. In this paper a modified fuzzy TOPSIS methodology is proposed for the selection of appropriate disposal method and site for municipal solid waste (MSW). Our method is superior to existing methods since it has capability of representing vague qualitative data and presenting all possible results with different degrees of membership. In the first stage of the proposed methodology, a set of criteria of cost, reliability, feasibility, pollution and emission levels, waste and energy recovery is optimized to determine the best MSW disposal method. Landfilling, composting, conventional incineration, and refuse-derived fuel (RDF) combustion are the alternatives considered. The weights of the selection criteria are determined by fuzzy pairwise comparison matrices of Analytic Hierarchy Process (AHP). It is found that RDF combustion is the best disposal method alternative for Istanbul. In the second stage, the same methodology is used to determine the optimum RDF combustion plant location using adjacent land use, climate, road access and cost as the criteria. The results of this study illustrate the importance of the weights on the various factors in deciding the optimized location, with the best site located in Catalca. A sensitivity analysis is also conducted to monitor how sensitive our model is to changes in the various criteria weights.

  16. Novel Triazole-Quinoline Derivatives as Selective Dual Binding Site Acetylcholinesterase Inhibitors.

    PubMed

    Mantoani, Susimaire P; Chierrito, Talita P C; Vilela, Adriana F L; Cardoso, Carmen L; Martínez, Ana; Carvalho, Ivone

    2016-02-05

    Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder worldwide. Currently, the only strategy for palliative treatment of AD is to inhibit acetylcholinesterase (AChE) in order to increase the concentration of acetylcholine in the synaptic cleft. Evidence indicates that AChE also interacts with the β-amyloid (Aβ) protein, acting as a chaperone and increasing the number and neurotoxicity of Aβ fibrils. It is known that AChE has two binding sites: the peripheral site, responsible for the interactions with Aβ, and the catalytic site, related with acetylcholine hydrolysis. In this work, we reported the synthesis and biological evaluation of a library of new tacrine-donepezil hybrids, as a potential dual binding site AChE inhibitor, containing a triazole-quinoline system. The synthesis of hybrids was performed in four steps using the click chemistry strategy. These compounds were evaluated as hAChE and hBChE inhibitors, and some derivatives showed IC50 values in the micro-molar range and were remarkably selective towards hAChE. Kinetic assays and molecular modeling studies confirm that these compounds block both catalytic and peripheral AChE sites. These results are quite interesting since the triazole-quinoline system is a new structural scaffold for AChE inhibitors. Furthermore, the synthetic approach is very efficient for the preparation of target compounds, allowing a further fruitful new chemical library optimization.

  17. Brachytherapy for clinically localized prostate cancer: optimal patient selection.

    PubMed

    Kollmeier, Marisa A; Zelefsky, Michael J

    2011-10-01

    The objective of this review is to present an overview of each modality and delineate how to best select patients who are optimal candidates for these treatment approaches. Prostate brachytherapy as a curative modality for clinically localized prostate cancer has become increasingly utilized over the past decade; 25% of all early cancers are now treated this way in the United States (1). The popularity of this treatment strategy lies in the highly conformal nature of radiation dose, low morbidity, patient convenience, and high efficacy rates. Prostate brachytherapy can be delivered by either a permanent interstitial radioactive seed implantation (low dose rate [LDR]) or a temporary interstitial insertion of iridium-192 (Ir192) afterloading catheters. The objective of both of these techniques is to deliver a high dose of radiation to the prostate gland while exposing normal surrounding tissues to minimal radiation dose. Brachytherapy techniques are ideal to achieve this goal given the close proximity of the radiation source to tumor and sharp fall off of the radiation dose cloud proximate to the source. Brachytherapy provides a powerful means of delivering dose escalation above and beyond that achievable with intensity-modulated external beam radiotherapy alone. Careful selection of appropriate patients for these therapies, however, is critical for optimizing both disease-related outcomes and treatment-related toxicity.

  18. Optimal subinterval selection approach for power system transient stability simulation

    DOE PAGES

    Kim, Soobae; Overbye, Thomas J.

    2015-10-21

    Power system transient stability analysis requires an appropriate integration time step to avoid numerical instability as well as to reduce computational demands. For fast system dynamics, which vary more rapidly than what the time step covers, a fraction of the time step, called a subinterval, is used. However, the optimal value of this subinterval is not easily determined because the analysis of the system dynamics might be required. This selection is usually made from engineering experiences, and perhaps trial and error. This paper proposes an optimal subinterval selection approach for power system transient stability analysis, which is based on modalmore » analysis using a single machine infinite bus (SMIB) system. Fast system dynamics are identified with the modal analysis and the SMIB system is used focusing on fast local modes. An appropriate subinterval time step from the proposed approach can reduce computational burden and achieve accurate simulation responses as well. As a result, the performance of the proposed method is demonstrated with the GSO 37-bus system.« less

  19. Optimal subinterval selection approach for power system transient stability simulation

    SciTech Connect

    Kim, Soobae; Overbye, Thomas J.

    2015-10-21

    Power system transient stability analysis requires an appropriate integration time step to avoid numerical instability as well as to reduce computational demands. For fast system dynamics, which vary more rapidly than what the time step covers, a fraction of the time step, called a subinterval, is used. However, the optimal value of this subinterval is not easily determined because the analysis of the system dynamics might be required. This selection is usually made from engineering experiences, and perhaps trial and error. This paper proposes an optimal subinterval selection approach for power system transient stability analysis, which is based on modal analysis using a single machine infinite bus (SMIB) system. Fast system dynamics are identified with the modal analysis and the SMIB system is used focusing on fast local modes. An appropriate subinterval time step from the proposed approach can reduce computational burden and achieve accurate simulation responses as well. As a result, the performance of the proposed method is demonstrated with the GSO 37-bus system.

  20. Optimizing Hammermill Performance Through Screen Selection and Hammer Design

    SciTech Connect

    Neal A. Yancey; Tyler L. Westover; Christopher T. Wright

    2013-01-01

    Background: Mechanical preprocessing, which includes particle size reduction and mechanical separation, is one of the primary operations in the feedstock supply system for a lignocellulosic biorefinery. It is the means by which raw biomass from the field or forest is mechanically transformed into an on-spec feedstock with characteristics better suited for the fuel conversion process. Results: This work provides a general overview of the objectives and methodologies of mechanical preprocessing and then presents experimental results illustrating (1) improved size reduction via optimization of hammer mill configuration, (2) improved size reduction via pneumatic-assisted hammer milling, and (3) improved control of particle size and particle size distribution through proper selection of grinder process parameters. Conclusion: Optimal grinder configuration for maximal process throughput and efficiency is strongly dependent on feedstock type and properties, such moisture content. Tests conducted using a HG200 hammer grinder indicate that increasing the tip speed, optimizing hammer geometry, and adding pneumatic assist can increase grinder throughput as much as 400%.

  1. Optimal Selection of Threshold Value 'r' for Refined Multiscale Entropy.

    PubMed

    Marwaha, Puneeta; Sunkaria, Ramesh Kumar

    2015-12-01

    Refined multiscale entropy (RMSE) technique was introduced to evaluate complexity of a time series over multiple scale factors 't'. Here threshold value 'r' is updated as 0.15 times SD of filtered scaled time series. The use of fixed threshold value 'r' in RMSE sometimes assigns very close resembling entropy values to certain time series at certain temporal scale factors and is unable to distinguish different time series optimally. The present study aims to evaluate RMSE technique by varying threshold value 'r' from 0.05 to 0.25 times SD of filtered scaled time series and finding optimal 'r' values for each scale factor at which different time series can be distinguished more effectively. The proposed RMSE was used to evaluate over HRV time series of normal sinus rhythm subjects, patients suffering from sudden cardiac death, congestive heart failure, healthy adult male, healthy adult female and mid-aged female groups as well as over synthetic simulated database for different datalengths 'N' of 3000, 3500 and 4000. The proposed RMSE results in improved discrimination among different time series. To enhance the computational capability, empirical mathematical equations have been formulated for optimal selection of threshold values 'r' as a function of SD of filtered scaled time series and datalength 'N' for each scale factor 't'.

  2. Site Selection for a Deep Monitor Well, Kualapuu, Molokai, Hawaii

    USGS Publications Warehouse

    Oki, Delwyn S.

    2000-01-01

    Management of the ground-water resources near Kualapuu on the island of Molokai, Hawaii, is hindered by the uncertainty in the vertical salinity structure in the aquifer. In the State of Hawaii, vertical profiles of ground-water salinity are commonly obtained from deep monitor wells, and these profiles are used to estimate the thicknesses of the freshwater part of the ground-water flow system and the freshwater-saltwater transition zone. Information from a deep monitor well would improve the understanding of the ground-water flow system and the ability to effectively manage the ground-water resources near Kualapuu; however, as of mid-1999 no deep monitor wells had been drilled on the island of Molokai. Selection of an appropriate site for drilling a deep monitor well in the Kualapuu area depends partly on where future ground-water development may occur. Simulations using an areally two-dimensional, steady-state, sharp-interface ground-water flow model previously developed for the island of Molokai, Hawaii, indicate that the southeastern part of the Kualapuu area is a possible area of future ground-water development because (1) withdrawals from this area have a small effect on water levels at existing wells in the Kualapuu area (relative to effects from withdrawals in other parts of the Kualapuu area that are outside of the dike complex), and (2) model-calculated water levels in this part of the Kualapuu area are high relative to water levels in other parts of the Kualapuu area that are outside of the dike complex. Additional site-selection criteria include (1) ground-water level, (2) ground-surface altitude, (3) land classification, ownership, and accessibility, (4) geology, (5) locations of existing production wells, and (6) historical ground-water quality information. A deep monitor well in the Kualapuu area will likely be most useful for management purposes if it is located (1) in the vicinity of future ground-water development, (2) in an area where water levels

  3. Ant colony optimization with selective evaluation for feature selection in character recognition

    NASA Astrophysics Data System (ADS)

    Oh, Il-Seok; Lee, Jin-Seon

    2010-01-01

    This paper analyzes the size characteristics of character recognition domain with the aim of developing a feature selection algorithm adequate for the domain. Based on the results, we further analyze the timing requirements of three popular feature selection algorithms, greedy algorithm, genetic algorithm, and ant colony optimization. For a rigorous timing analysis, we adopt the concept of atomic operation. We propose a novel scheme called selective evaluation to improve convergence of ACO. The scheme cut down the computational load by excluding the evaluation of unnecessary or less promising candidate solutions. The scheme is realizable in ACO due to the valuable information, pheromone trail which helps identify those solutions. Experimental results showed that the ACO with selective evaluation was promising both in timing requirement and recognition performance.

  4. Protein fragment swapping: a method for asymmetric, selective site-directed recombination.

    PubMed

    Zheng, Wei; Griswold, Karl E; Bailey-Kellogg, Chris

    2010-03-01

    This article presents a new approach to site-directed recombination, swapping combinations of selected discontiguous fragments from a source protein in place of corresponding fragments of a target protein. By being both asymmetric (differentiating source and target) and selective (swapping discontiguous fragments), our method focuses experimental effort on a more restricted portion of sequence space, constructing hybrids that are more likely to have the properties that are the objective of the experiment. Furthermore, since the source and target need to be structurally homologous only locally (rather than overall), our method supports swapping fragments from functionally important regions of a source into a target "scaffold" (for example, to humanize an exogenous therapeutic protein). A protein fragment swapping plan is defined by the residue position boundaries of the fragments to be swapped; it is assessed by an average potential score over the resulting hybrid library, with singleton and pairwise terms evaluating the importance and fit of the swapped residues. While we prove that it is NP-hard to choose an optimal set of fragments under such a potential score, we develop an integer programming approach, which we call Swagmer, that works very well in practice. We demonstrate the effectiveness of our method in three swapping problems: selective recombination between beta-lactamases, activity swapping between glutathione transferases, and activity swapping between carboxylases and mutases in the purE family. We show that the selective recombination approach generates better plan (in terms of resulting potential score) than traditional site-directed recombination approaches. We also show that in all cases the optimized experiments are significantly better than ones that would result from stochastic methods.

  5. 40 CFR 228.5 - General criteria for the selection of sites.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... DUMPING CRITERIA FOR THE MANAGEMENT OF DISPOSAL SITES FOR OCEAN DUMPING § 228.5 General criteria for the selection of sites. (a) The dumping of materials into the ocean will be permitted only at sites or in areas... ocean dumping sites beyond the edge of the continental shelf and other such sites that have...

  6. Optimal experiment design for model selection in biochemical networks

    PubMed Central

    2014-01-01

    Background Mathematical modeling is often used to formalize hypotheses on how a biochemical network operates by discriminating between competing models. Bayesian model selection offers a way to determine the amount of evidence that data provides to support one model over the other while favoring simple models. In practice, the amount of experimental data is often insufficient to make a clear distinction between competing models. Often one would like to perform a new experiment which would discriminate between competing hypotheses. Results We developed a novel method to perform Optimal Experiment Design to predict which experiments would most effectively allow model selection. A Bayesian approach is applied to infer model parameter distributions. These distributions are sampled and used to simulate from multivariate predictive densities. The method is based on a k-Nearest Neighbor estimate of the Jensen Shannon divergence between the multivariate predictive densities of competing models. Conclusions We show that the method successfully uses predictive differences to enable model selection by applying it to several test cases. Because the design criterion is based on predictive distributions, which can be computed for a wide range of model quantities, the approach is very flexible. The method reveals specific combinations of experiments which improve discriminability even in cases where data is scarce. The proposed approach can be used in conjunction with existing Bayesian methodologies where (approximate) posteriors have been determined, making use of relations that exist within the inferred posteriors. PMID:24555498

  7. Validation of the optimal site in the neck region for detecting swallowing sounds.

    PubMed

    Pan, Q; Maeda, N; Manda, Y; Kodama, N; Minagi, S

    2016-11-01

    Recently, the swallowing sound has been used to detect swallowing events non-invasively. A previous study, using an accelerometer, showed that the site over the lateral border of the trachea immediately inferior to the cricoid cartilage was the optimal site for detecting swallowing sounds. However, the optimal site for detection of the swallowing sound using a microphone remains undetermined. To validate the optimal site in the neck region for detecting swallowing sounds. Fourteen healthy subjects (mean age, 27·6 ± 2·2 years; seven male and seven female) participated in this study. Twenty condenser microphones were attached to 20 sites on the left neck surface to detect swallowing sounds. Participants were instructed to swallow five different stimuli three times as follows: Resting saliva, 1 and 5 mL of Japanese tea, and 1 and 5 mL of yoghurt. Mean relative peak intensity was used to indicate the magnitude of the swallowing sound. Sound spectrograms were used to illustrate differences in the properties of swallowing sounds. Mean relative peak intensity number was highest in sites at the inferior border of the mandible just above the sternocleidomastoid muscle (site 11) and sites over the lateral border of the trachea immediately inferior to the cricoid cartilage (site 8). Comparison of spectrograms showed a greater density distribution of higher frequency components at site 11 compared with site 8. These results indicate that the inferior border of the mandible just above the sternocleidomastoid muscle is the optimal site for the detection of swallowing sounds.

  8. Influenza B vaccine lineage selection--an optimized trivalent vaccine.

    PubMed

    Mosterín Höpping, Ana; Fonville, Judith M; Russell, Colin A; James, Sarah; Smith, Derek J

    2016-03-18

    Epidemics of seasonal influenza viruses cause considerable morbidity and mortality each year. Various types and subtypes of influenza circulate in humans and evolve continuously such that individuals at risk of serious complications need to be vaccinated annually to keep protection up to date with circulating viruses. The influenza vaccine in most parts of the world is a trivalent vaccine, including an antigenically representative virus of recently circulating influenza A/H3N2, A/H1N1, and influenza B viruses. However, since the 1970s influenza B has split into two antigenically distinct lineages, only one of which is represented in the annual trivalent vaccine at any time. We describe a lineage selection strategy that optimizes protection against influenza B using the standard trivalent vaccine as a potentially cost effective alternative to quadrivalent vaccines.

  9. Ensemble of Surrogates-based Optimization for Identifying an Optimal Surfactant-enhanced Aquifer Remediation Strategy at Heterogeneous DNAPL-contaminated Sites

    NASA Astrophysics Data System (ADS)

    Lu, W., Sr.; Xin, X.; Luo, J.; Jiang, X.; Zhang, Y.; Zhao, Y.; Chen, M.; Hou, Z.; Ouyang, Q.

    2015-12-01

    The purpose of this study was to identify an optimal surfactant-enhanced aquifer remediation (SEAR) strategy for aquifers contaminated by dense non-aqueous phase liquid (DNAPL) based on an ensemble of surrogates-based optimization technique. A saturated heterogeneous medium contaminated by nitrobenzene was selected as case study. A new kind of surrogate-based SEAR optimization employing an ensemble surrogate (ES) model together with a genetic algorithm (GA) is presented. Four methods, namely radial basis function artificial neural network (RBFANN), kriging (KRG), support vector regression (SVR), and kernel extreme learning machines (KELM), were used to create four individual surrogate models, which were then compared. The comparison enabled us to select the two most accurate models (KELM and KRG) to establish an ES model of the SEAR simulation model, and the developed ES model as well as these four stand-alone surrogate models was compared. The results showed that the average relative error of the average nitrobenzene removal rates between the ES model and the simulation model for 20 test samples was 0.8%, which is a high approximation accuracy, and which indicates that the ES model provides more accurate predictions than the stand-alone surrogate models. Then, a nonlinear optimization model was formulated for the minimum cost, and the developed ES model was embedded into this optimization model as a constrained condition. Besides, GA was used to solve the optimization model to provide the optimal SEAR strategy. The developed ensemble surrogate-optimization approach was effective in seeking a cost-effective SEAR strategy for heterogeneous DNAPL-contaminated sites. This research is expected to enrich and develop the theoretical and technical implications for the analysis of remediation strategy optimization of DNAPL-contaminated aquifers.

  10. Autonomous site selection and instrument positioning for sample acquisition

    NASA Astrophysics Data System (ADS)

    Shaw, A.; Barnes, D.; Pugh, S.

    The European Space Agency Aurora Exploration Program aims to establish a European long-term programme for the exploration of Space, culminating in a human mission to space in the 2030 timeframe. Two flagship missions, namely Mars Sample Return and ExoMars, have been proposed as recognised steps along the way. The Exomars Rover is the first of these flagship missions and includes a rover carrying the Pasteur Payload, a mobile exobiology instrumentation package, and the Beagle 2 arm. The primary objective is the search for evidence of past or present life on mars, but the payload will also study the evolution of the planet and the atmosphere, look for evidence of seismological activity and survey the environment in preparation for future missions. The operation of rovers in unknown environments is complicated, and requires large resources not only on the planet but also in ground based operations. Currently, this can be very labour intensive, and costly, if large teams of scientists and engineers are required to assess mission progress, plan mission scenarios, and construct a sequence of events or goals for uplink. Furthermore, the constraints in communication imposed by the time delay involved over such large distances, and line-of-sight required, make autonomy paramount to mission success, affording the ability to operate in the event of communications outages and be opportunistic with respect to scientific discovery. As part of this drive to reduce mission costs and increase autonomy the Space Robotics group at the University of Wales, Aberystwyth is researching methods of autonomous site selection and instrument positioning, directly applicable to the ExoMars mission. The site selection technique used builds on the geometric reasoning algorithms used previously for localisation and navigation [Shaw 03]. It is proposed that a digital elevation model (DEM) of the local surface, generated during traverse and without interaction from ground based operators, can be

  11. Coordination chemistry of phosphinocarbynes: phosphorus vs. carbyne site selectivity.

    PubMed

    Colebatch, Annie L; Hill, Anthony F

    2017-03-13

    The phosphinocarbyne complex [W([triple bond, length as m-dash]CPPh2)(CO)2(Tp*)] (1: Tp* = hydrotris(dimethylpyrazolyl)borate) coordinates transition metal fragments via the phosphine to form bimetallic species [W{[triple bond, length as m-dash]CPPh2RhCl2(Cp*)}(CO)2(Tp*)] (2) and [W([triple bond, length as m-dash]CPPh2AuCl)(CO)2(Tp*)] (3). Appropriately tailored sterics allow for complexation of a second equivalent of AuCl to afford the trimetallic complex [W{η(2)-C(AuCl)PPh2AuCl}(CO)2(Tp*)] (4), containing an Au-W-C dimetallacyclopropene connectivity. Similarly, AuCl binds to the carbyne linkage in [W{[triple bond, length as m-dash]CP([double bond, length as m-dash]S)Ph2}(CO)2(Tp*)], yielding [W{η(2)-C(AuCl)P([double bond, length as m-dash]S)Ph2}(CO)2(Tp*)] (5). In the case of auration of the ditungsten species [W2(μ-C2PPh)(CO)4(Tp*)2] (6), variation in the stoichiometry leads to trimetallic [W2(μ-C2PPhAuCl)(CO)4(Tp*)2] (7) and pentametallic [W2{μ-(η(2)-CAuCl)2PPhAuCl}(CO)4(Tp*)2] (8) complexes, via a proposed tetrametallic intermediate [W2{μ-(η(2)-CAuCl)2PPh}(CO)4(Tp*)2], the site selectivity being dictated by aurophilic interactions.

  12. Regional Consumer Hydrogen Demand and Optimal Hydrogen Refueling Station Siting

    SciTech Connect

    Melendez, M.; Milbrandt, A.

    2008-04-01

    Using a GIS approach to spatially analyze key attributes affecting hydrogen market transformation, this study proposes hypothetical hydrogen refueling station locations in select subregions to demonstrate a method for determining station locations based on geographic criteria.

  13. 40 CFR 228.5 - General criteria for the selection of sites.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... DUMPING CRITERIA FOR THE MANAGEMENT OF DISPOSAL SITES FOR OCEAN DUMPING § 228.5 General criteria for the selection of sites. (a) The dumping of materials into the ocean will be permitted only at sites or in areas selected to minimize the interference of disposal activities with other activities in the...

  14. 40 CFR 228.5 - General criteria for the selection of sites.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... DUMPING CRITERIA FOR THE MANAGEMENT OF DISPOSAL SITES FOR OCEAN DUMPING § 228.5 General criteria for the selection of sites. (a) The dumping of materials into the ocean will be permitted only at sites or in areas selected to minimize the interference of disposal activities with other activities in the...

  15. Optimization of killer assays for yeast selection protocols.

    PubMed

    Lopes, C A; Sangorrín, M P

    2010-01-01

    A new optimized semiquantitative yeast killer assay is reported for the first time. The killer activity of 36 yeast isolates belonging to three species, namely, Metschnikowia pulcherrima, Wickerhamomyces anomala and Torulaspora delbrueckii, was tested with a view to potentially using these yeasts as biocontrol agents against the wine spoilage species Pichia guilliermondii and Pichia membranifaciens. The effectiveness of the classical streak-based (qualitative method) and the new semiquantitative techniques was compared. The percentage of yeasts showing killer activity was found to be higher by the semiquantitative technique (60%) than by the qualitative method (45%). In all cases, the addition of 1% NaCl into the medium allowed a better observation of the killer phenomenon. Important differences were observed in the killer capacity of different isolates belonging to a same killer species. The broadest spectrum of action was detected in isolates of W. anomala NPCC 1023 and 1025, and M. pulcherrima NPCC 1009 and 1013. We also brought experimental evidence supporting the importance of the adequate selection of the sensitive isolate to be used in killer evaluation. The new semiquantitative method proposed in this work enables to visualize the relationship between the number of yeasts tested and the growth of the inhibition halo (specific productivity). Hence, this experimental approach could become an interesting tool to be taken into account for killer yeast selection protocols.

  16. Optimized bioregenerative space diet selection with crew choice.

    PubMed

    Vicens, Carrie; Wang, Carolyn; Olabi, Ammar; Jackson, Peter; Hunter, Jean

    2003-01-01

    Previous studies on optimization of crew diets have not accounted for choice. A diet selection model with crew choice was developed. Scenario analyses were conducted to assess the feasibility and cost of certain crew preferences, such as preferences for numerous-desserts, high-salt, and high-acceptability foods. For comparison purposes, a no-choice and a random-choice scenario were considered. The model was found to be feasible in terms of food variety and overall costs. The numerous-desserts, high-acceptability, and random-choice scenarios all resulted in feasible solutions costing between 13.2 and 17.3 kg ESM/person-day. Only the high-sodium scenario yielded an infeasible solution. This occurred when the foods highest in salt content were selected for the crew-choice portion of the diet. This infeasibility can be avoided by limiting the total sodium content in the crew-choice portion of the diet. Cost savings were found by reducing food variety in scenarios where the preference bias strongly affected nutritional content.

  17. Optimized bioregenerative space diet selection with crew choice

    NASA Technical Reports Server (NTRS)

    Vicens, Carrie; Wang, Carolyn; Olabi, Ammar; Jackson, Peter; Hunter, Jean

    2003-01-01

    Previous studies on optimization of crew diets have not accounted for choice. A diet selection model with crew choice was developed. Scenario analyses were conducted to assess the feasibility and cost of certain crew preferences, such as preferences for numerous-desserts, high-salt, and high-acceptability foods. For comparison purposes, a no-choice and a random-choice scenario were considered. The model was found to be feasible in terms of food variety and overall costs. The numerous-desserts, high-acceptability, and random-choice scenarios all resulted in feasible solutions costing between 13.2 and 17.3 kg ESM/person-day. Only the high-sodium scenario yielded an infeasible solution. This occurred when the foods highest in salt content were selected for the crew-choice portion of the diet. This infeasibility can be avoided by limiting the total sodium content in the crew-choice portion of the diet. Cost savings were found by reducing food variety in scenarios where the preference bias strongly affected nutritional content.

  18. The Use of Collective Dose for Optimization of a Low-Level Waste Site Closure Cover

    SciTech Connect

    Greg Shott, Vefa Yucel

    2010-03-07

    Low-level radioactive waste management regulations require that releases to the environment be as low as reasonably achievable. Collective dose’s use in quantitative cost benefit analysis is well accepted for optimization of operational radiation safety, but seldom applied to routine environmental releases. One concern is that collective dose for large areas and long time periods may obscure the spatial and temporal distribution of risk and the magnitude of individual doses. Use of collective dose for optimization also requires that the decision maker justify subjective inputs including truncation limits for the summation of collective dose in space and time, a monetary value for collective dose, and a discount rate for future health detriment. In this study, a probabilistic collective dose model is developed and used to optimize the closure of the Area 5 Radioactive Waste Management Site (RWMS) on the Nevada Test Site. Collective dose’s shortcomings are addressed by preparing a dose matrix that disaggregates the collective dose in space and time and by reporting individual doses for exposed subgroups. Important subjective inputs are assigned discrete values reflecting differing opinions, and the consequence of the differences on the final decision is described. The resulting optimization process remains subjective, but clearly identifies subjective inputs, the values selected, and their impact on the decision. For the Area 5 RWMS, the value of the collective dose is small compared to closure cover cost options over a broad range of subjective values for the spatial and temporal limits for truncation of collective dose, monetary value of collective dose, and discount rates for future dose. The collective dose matrix and individual doses indicate that the societal and individual risks are greatest for future residents within the disposal site boundary, suggesting that options deterring intrusion have the greatest potential for cost-effectiveness. The cost of

  19. OSU TOMF Program Site Selection and Preliminary Concept Design Report

    SciTech Connect

    Spadling, Steve

    2012-05-10

    The purpose of this report is to confirm the programmatic requirements for the new facilities, identify the most appropriate project site, and develop preliminary site and building concepts that successfully address the overall project goals and site issues. These new facilities will be designed to accommodate the staff, drivers and maintenance requirements for the future mixed fleet of passenger vehicles, Transit Style Buses and School Buses.

  20. [Hyperspectral remote sensing image classification based on SVM optimized by clonal selection].

    PubMed

    Liu, Qing-Jie; Jing, Lin-Hai; Wang, Meng-Fei; Lin, Qi-Zhong

    2013-03-01

    Model selection for support vector machine (SVM) involving kernel and the margin parameter values selection is usually time-consuming, impacts training efficiency of SVM model and final classification accuracies of SVM hyperspectral remote sensing image classifier greatly. Firstly, based on combinatorial optimization theory and cross-validation method, artificial immune clonal selection algorithm is introduced to the optimal selection of SVM (CSSVM) kernel parameter a and margin parameter C to improve the training efficiency of SVM model. Then an experiment of classifying AVIRIS in India Pine site of USA was performed for testing the novel CSSVM, as well as a traditional SVM classifier with general Grid Searching cross-validation method (GSSVM) for comparison. And then, evaluation indexes including SVM model training time, classification overall accuracy (OA) and Kappa index of both CSSVM and GSSVM were all analyzed quantitatively. It is demonstrated that OA of CSSVM on test samples and whole image are 85.1% and 81.58, the differences from that of GSSVM are both within 0.08% respectively; And Kappa indexes reach 0.8213 and 0.7728, the differences from that of GSSVM are both within 0.001; While the ratio of model training time of CSSVM and GSSVM is between 1/6 and 1/10. Therefore, CSSVM is fast and accurate algorithm for hyperspectral image classification and is superior to GSSVM.

  1. Optimizing Curriculum Planning in Site-Based Management.

    ERIC Educational Resources Information Center

    Stewart, William J.

    1997-01-01

    Examines why curriculum planning falls short in site-based management and what can be done about it. Alternative curriculum-planning strategies include holistic planning, construction of thematic units to suit students' individual differences, and a multifaceted, cross-functional approach. Adapting corporate innovations and pursuing strategic…

  2. Estimates of External Validity Bias When Impact Evaluations Select Sites Nonrandomly

    ERIC Educational Resources Information Center

    Bell, Stephen H.; Olsen, Robert B.; Orr, Larry L.; Stuart, Elizabeth A.

    2016-01-01

    Evaluations of educational programs or interventions are typically conducted in nonrandomly selected samples of schools or districts. Recent research has shown that nonrandom site selection can yield biased impact estimates. To estimate the external validity bias from nonrandom site selection, we combine lists of school districts that were…

  3. Site-selective hydrolysis of tRNA by lanthanide metal complexes

    SciTech Connect

    Hayashi, Nobuhiro ); Takeda, Naoya; Yashiro, Morio; Watanabe, Kimitsuna; Komiyama, Makoto ); Shiiba, Tetsuro )

    1993-12-22

    tRNA[sup Phe] is site-selectively hydrolyzed by lanthanide metal complexes (Ce(III), Eu(III), La(III)) of hexaimine macrocyclic ligands. The selectivities of the complexes are much higher than those of the metal ions and are strongly dependent on the ligand structure. The tertiary structure of tRNA is essential for the site-selective scission.

  4. Site location optimization of regional air quality monitoring network in China: methodology and case study.

    PubMed

    Zheng, Junyu; Feng, Xiaoqiong; Liu, Panwei; Zhong, Liuju; Lai, Senchao

    2011-11-01

    Regional air quality monitoring networks (RAQMN) are urgently needed in China due to increasing regional air pollution in city clusters, arising from rapid economic development in recent decades. This paper proposes a methodological framework for site location optimization in designing a RAQMN adapting to air quality management practice in China. The framework utilizes synthetic assessment concentrations developed from simulated data from a regional air quality model in order to simplify the optimal process and to reduce costs. On the basis of analyzing various constraints such as cost and budget, terrain conditions, administrative district, population density and spatial coverage, the framework takes the maximum approximate degree as an optimization objective to achieve site location optimization of a RAQMN. An expert judgment approach was incorporated into the framework to help adjust initial optimization results in order to make the network more practical and representative. A case study was used to demonstrate the application of the framework, indicating that it is feasible to conduct site optimization for a RAQMN design in China. The effects of different combinations of primary and secondary pollutants on site location optimization were investigated. It is suggested that the network design considering both primary and secondary pollutants could better represent regional pollution characteristics and more extensively reflect temporal and spatial variations of regional air quality. The work shown in this study can be used as a reference to guide site location optimization of a RAQMN design in China or other regions of the world.

  5. Highly selective Lewis acid sites in desilicated MFI zeolites for dihydroxyacetone isomerization to lactic acid.

    PubMed

    Dapsens, Pierre Y; Mondelli, Cecilia; Pérez-Ramírez, Javier

    2013-05-01

    Desilication of commercial MFI-type (ZSM-5) zeolites in solutions of alkali metal hydroxides is demonstrated to generate highly selective heterogeneous catalysts for the aqueous-phase isomerization of biobased dihydroxyacetone (DHA) to lactic acid (LA). The best hierarchical ZSM-5 sample attains a LA selectivity exceeding 90 %, which is comparable to that of the state-of-the-art catalyst (i.e., the Sn-beta zeolite); this optimized hierarchical catalyst is recyclable over three runs. The Lewis acid sites, which are created through desilication along with the introduction of mesoporosity, are shown to play a crucial role in the formation of the desired product; these cannot be achieved by using other post-synthetic methods, such as steaming or impregnation of aluminum species. Desilication of other metallosilicates, such as Ga-MFI, also leads to high LA selectivity. In the presence of a soluble aluminum source, such as aluminum nitrate, alkaline-assisted alumination can introduce these unique Lewis acid centers in all-silica MFI zeolites. These findings highlight the potential of zeolites in the field of biomass-to-chemical conversion, and expand the applicability of desilication for the generation of selective catalytic centers.

  6. Selective Sirt2 inhibition by ligand-induced rearrangement of the active site.

    PubMed

    Rumpf, Tobias; Schiedel, Matthias; Karaman, Berin; Roessler, Claudia; North, Brian J; Lehotzky, Attila; Oláh, Judit; Ladwein, Kathrin I; Schmidtkunz, Karin; Gajer, Markus; Pannek, Martin; Steegborn, Clemens; Sinclair, David A; Gerhardt, Stefan; Ovádi, Judit; Schutkowski, Mike; Sippl, Wolfgang; Einsle, Oliver; Jung, Manfred

    2015-02-12

    Sirtuins are a highly conserved class of NAD(+)-dependent lysine deacylases. The human isotype Sirt2 has been implicated in the pathogenesis of cancer, inflammation and neurodegeneration, which makes the modulation of Sirt2 activity a promising strategy for pharmaceutical intervention. A rational basis for the development of optimized Sirt2 inhibitors is lacking so far. Here we present high-resolution structures of human Sirt2 in complex with highly selective drug-like inhibitors that show a unique inhibitory mechanism. Potency and the unprecedented Sirt2 selectivity are based on a ligand-induced structural rearrangement of the active site unveiling a yet-unexploited binding pocket. Application of the most potent Sirtuin-rearranging ligand, termed SirReal2, leads to tubulin hyperacetylation in HeLa cells and induces destabilization of the checkpoint protein BubR1, consistent with Sirt2 inhibition in vivo. Our structural insights into this unique mechanism of selective sirtuin inhibition provide the basis for further inhibitor development and selective tools for sirtuin biology.

  7. The genealogy of sequences containing multiple sites subject to strong selection in a subdivided population.

    PubMed

    Nordborg, Magnus; Innan, Hideki

    2003-03-01

    A stochastic model for the genealogy of a sample of recombining sequences containing one or more sites subject to selection in a subdivided population is described. Selection is incorporated by dividing the population into allelic classes and then conditioning on the past sizes of these classes. The past allele frequencies at the selected sites are thus treated as parameters rather than as random variables. The purpose of the model is not to investigate the dynamics of selection, but to investigate effects of linkage to the selected sites on the genealogy of the surrounding chromosomal region. This approach is useful for modeling strong selection, when it is natural to parameterize the past allele frequencies at the selected sites. Several models of strong balancing selection are used as examples, and the effects on the pattern of neutral polymorphism in the chromosomal region are discussed. We focus in particular on the statistical power to detect balancing selection when it is present.

  8. Rocky Mountain Snowpack Chemistry at Selected Sites, 2002

    USGS Publications Warehouse

    Ingersoll, George P.; Mast, M. Alisa; Nanus, Leora; Manthorne, David J.; Clow, David W.; Handran, Heather M.; Winterringer, Jesse A.; Campbell, Donald H.

    2004-01-01

    During spring 2002, the chemical composition of annual snowpacks in the Rocky Mountain region of the Western United States was analyzed. Snow samples were collected at 75 geographically distributed sites extending from New Mexico to Montana. Near the end of the 2002 snowfall season, the snow-water equivalent (SWE) in annual snowpacks sampled generally was below average in most of the region. Regional patterns in the concentrations of major ions (including ammonium, nitrate, and sulfate), mercury, and stable sulfur isotope ratios are presented. The 2002 snowpack chemistry in the region differed from the previous year. Snowpack ammonium concentrations were higher at 66 percent of sites in Montana compared to concentrations in the 2001 snowpack but were lower at 74 percent of sites in Wyoming, Colorado, and New Mexico. Nitrate was lower at all Montana sites and lower at all but one Wyoming site; nitrate was higher at all but two Colorado sites and higher at all New Mexico sites. Sulfate was lower across the region at 77 percent of sites. The range of mercury concentrations for the region was similar to those of 2001 but showed more variability than ammonium, nitrate, and sulfate concentrations. Concentrations of stable sulfur isotope ratios exhibited a strong regional pattern with values increasing northward from southern Colorado to northern Colorado and Wyoming.

  9. 40 CFR 228.6 - Specific criteria for site selection.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... 228.6 Section 228.6 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE MANAGEMENT OF DISPOSAL SITES FOR OCEAN DUMPING § 228.6 Specific criteria for site... area, including prevailing current direction and velocity, if any; (7) Existence and effects of...

  10. Feasibility of growing olives on selected sites along coastal Texas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Five sites along the Texas coastline (Seadrift, Galveston, Brazoria, Santa Fe, and Orange) were evaluated for feasibility of growing olives in these areas. In addition, two non-coastal sites (Carrizo Springs and Weslaco) were also included in the study for comparative purposes. Flowering and fruit ...

  11. Determination of ecologically vital groundwaters at selected sites in the Formerly Utilized Sites Remedial Action Program

    SciTech Connect

    Vinikour, W.S.; Yin, S.C.L.

    1989-08-01

    The US Department of Energy is classifying groundwaters at sites in its Formerly Utilized Sites Remedial Action Program (FUSRAP). Of particular concern is the potential presence of groundwaters that are highly vulnerable to contamination and that are either (1) irreplaceable sources of drinking water or (2) ecologically vital. Conditions at nine FUSRAP sites were evaluated to determine if ecologically vital groundwaters are present. The sites evaluated were Wayne Interim Storage Site, Maywood Interim Storage Site, and Middlesex Sampling Plant in New Jersey; Ashland 2 Site, Seaway Industrial Park, Colonie Interim storage Site, and Niagara Falls Storage Site in New York; and the St. Louis Airport Site and Hazelwood Interim Storage Site in Missouri. The analyses indicated that groundwaters are vulnerable to contamination at all but two of the sites -- the Ashland 2 and Seaway Industrial Park sites in New York. Groundwater discharge points were identified within a 2-mile radius (i.e., the classification review area) of all of the sites. No ecologically vital groundwater areas exist in the vicinities of any of the nine FUSRAP sites evaluated. 35 refs., 17 figs.

  12. Selecting landing sites for the 2003 Mars Exploration Rovers

    NASA Astrophysics Data System (ADS)

    Grant, John A.; Golombek, Matthew P.; Parker, Timothy J.; Crisp, Joy A.; Squyres, Steven W.; Weitz, Catherine M.

    2004-01-01

    A two-plus year process of identifying and evaluating landing sites for the NASA 2003 Mars Exploration Rovers began with definition of mission science objectives, preliminary engineering requirements, and identification of ˜155 potential sites in near-equator locations (these included multiple ellipses for locations accessible by both rovers). Four open workshops were used together with ongoing engineering evaluations to narrow the list of sites to four: Meridiani Planum and Gusev Crater were ranked highest for science, with southern Isidis Basin and a "wind safe" site in Elysium following in order. Based on exhaustive community assessment, these sites comprise the best-studied locales on Mars and should possess attributes enabling mission success.

  13. Optimization Review Report: Saunders Supply Company Superfund Site Suffolk County, Virginia, EPA Region 3

    EPA Pesticide Factsheets

    This site is a 7-1/3 acre former wood treating plant. The source areas included wastewater ponds, treatment areas, and burn pits. This report summarizes the findings and recommendations of the optimization review team.

  14. Regulatory requirements for nuclear power plant site selection in Malaysia-a review.

    PubMed

    Basri, N A; Hashim, S; Ramli, A T; Bradley, D A; Hamzah, K

    2016-12-01

    Malaysia has initiated a range of pre-project activities in preparation for its planned nuclear power programme. Clearly one of the first steps is the selection of sites that are deemed suitable for the construction and operation of a nuclear power plant. Here we outline the Malaysian regulatory requirements for nuclear power plant site selection, emphasizing details of the selection procedures and site characteristics needed, with a clear focus on radiation safety and radiation protection in respect of the site surroundings. The Malaysia Atomic Energy Licensing Board (AELB) site selection guidelines are in accord with those provided in International Atomic Energy Agency (IAEA) and United Stated Nuclear Regulatory Commission (USNRC) documents. To enhance the suitability criteria during selection, as well as to assist in the final decision making process, possible assessments using the site selection characteristics and information are proposed.

  15. Investigation of pre-structured GaAs surfaces for subsequent site-selective InAs quantum dot growth

    NASA Astrophysics Data System (ADS)

    Helfrich, Mathieu; Gröger, Roland; Förste, Alexander; Litvinov, Dimitri; Gerthsen, Dagmar; Schimmel, Thomas; Schaadt, Daniel M.

    2011-12-01

    In this study, we investigated pre-structured (100) GaAs sample surfaces with respect to subsequent site-selective quantum dot growth. Defects occurring in the GaAs buffer layer grown after pre-structuring are attributed to insufficient cleaning of the samples prior to regrowth. Successive cleaning steps were analyzed and optimized. A UV-ozone cleaning is performed at the end of sample preparation in order to get rid of remaining organic contamination.

  16. Investigation of pre-structured GaAs surfaces for subsequent site-selective InAs quantum dot growth

    PubMed Central

    2011-01-01

    In this study, we investigated pre-structured (100) GaAs sample surfaces with respect to subsequent site-selective quantum dot growth. Defects occurring in the GaAs buffer layer grown after pre-structuring are attributed to insufficient cleaning of the samples prior to regrowth. Successive cleaning steps were analyzed and optimized. A UV-ozone cleaning is performed at the end of sample preparation in order to get rid of remaining organic contamination. PMID:21711729

  17. Cumberlandian Mollusk Conservation Program. Activity 9: selection of transplant sites and habitat characterization. [Conradilla caelata

    SciTech Connect

    Jenkinson, J.J.; Heuer, J.H.

    1986-02-01

    This report describes the selection process and the composite analysis of 15 short reaches of free flowing streams in which the physical, limnological, botanical, and zoological components were examined. The purpose was to identify combinations of environmental conditions which occur in the study areas that support populations of Cumberlandian freshwater mussels and to select transplant sites which could support populations of selected Cumberlandian mussel species, especially Conradilla caelata, once they were (re)introduced. This report is divided into three major sections (selection of study reaches, selection of transplant sites, and habitat characterization) two of which appear to fall in reverse order. Chronologically, transplant sites for the birdwing pearly mussel, Conradilla caelata, were selected before the characterization of mussel habitat could be completed. Since the transplants were made based upon the comparison of sites presented in that analysis, the site selection description was retained in an unmodified state.

  18. Kin, daytime associations, or preferred sleeping sites? Factors influencing sleep site selection in captive chimpanzees (Pan troglodytes).

    PubMed

    Lock, Louise C; Anderson, James R

    2013-01-01

    Chimpanzee nesting behaviours and the factors that may influence these behaviours are rarely studied in captive settings. In the present study, the daytime associations, sleeping site selections and nesting groups of 11 zoo-housed chimpanzees over a 29-day period were analysed. Neither daytime associations nor presence of kin influenced sleeping site selection in females. Daytime associations did influence sleeping arrangements in males. Nighttime spatial arrangements and individual preferences for specific sleeping areas were broadly comparable to nesting patterns reported in free-living chimpanzee communities. In the interests of captive ape welfare, we conclude that exhibits should incorporate multilevel nesting areas and a choice of several potential sleeping sites.

  19. Site-selective imination of an anthracenone sensor: selective fluorescence detection of barium(II).

    PubMed

    Basa, Prem N; Bhowmick, Arundhati; Schulz, Mariah M; Sykes, Andrew G

    2011-10-07

    Site-selective imination of anthraquinone-based macrocyclic crown ethers using titanium tetrachloride as the catalyst yields imines where only the external carbonyl group of the anthraquinone forms Schiff-bases. The following aromatic amines yield monomeric compounds (aniline, 4-nitroaniline, 4-pyrrolaniline, and 1,3-phenylenediamine). Reaction of 2 equiv of the macrocyclic anthraquinone host with 1,2- and 1,4-phenylenediamine yields dimeric imine compounds. The 1,2-diimino host acts as a luminescence sensor, exhibiting enhanced selectivity for Ba(II) ion. Spectroscopic data indicate that two barium ions coordinate to the sensor. Due to E/Z isomerization of the imine, the monomeric complexes are nonluminescent. Restricted rotation about the 1,2 oriented C═N groups or other noncovalent/coordinate-covalent interactions acting between neighboring crown ether rings may inhibit E/Z isomerization in this example, which is different from current examples that employ coordination of a metal cation with a chelating imine nitrogen atom to suppress E/Z isomerization and activate luminescence. The 1,4-diimino adduct, where the crown rings remain widely separated, remains nonluminescent.

  20. Final Report: Pilot Region-Based Optimization Program for Fund-Lead Sites, EPA Region III

    EPA Pesticide Factsheets

    This report describes a pilot study for a Region-based optimization program, implemented by a Regional Optimization Evaluation Team (ROET) that was conducted in U.S. EPA Region III at Fund-lead sites with pump-and-treat (P&T) systems.

  1. 20 CFR 638.303 - Site selection and facilities management.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... approve the location and size of all centers. (b) Contract centers shall be established, relocated or... centers, either the Job Corps Director or a Federal agency may propose a site on public lands and...

  2. Site Selection for Mars Surveyor Landing Sites: Some Key Factors for 2001 and Relation to Long-Term Exploration of Mars

    NASA Astrophysics Data System (ADS)

    Head, James W.

    1999-01-01

    The Site Selection Process: Site selection as a process can be subdivided into several main elements and these can be represented as the corners of a tetrahedron. Successful site selection outcome requires the interactions between these elements or corners, and should also take into account several other external factors or considerations. In principle, elements should be defined in approximately the following order: (1) major scientific and programmatic goals and objectives: What are the major questions that are being asked, goals that should be achieved, and objectives that must be accomplished. Do programmatic goals (e.g., sample return) differ from mission goals (e.g., precursor to sample return)? It is most helpful if these questions can be placed in the context of site characterization and hypothesis testing (e.g., Was Mars warm and wet in the Noachian? Land at a Noachian-aged site that shows evidence of surface water and characterize it specifically to address this question). Goals and objectives, then, help define important engineering factors such as type of payload, landing regions of interest (highlands, lowlands, smooth, rough, etc.), mobility, mission duration, etc. Goals and objectives then lead to: (2) spacecraft design and engineering landing site constraints: the spacecraft is designed to optimize the areas that will meet the goals and objectives, but this in turn introduces constraints that must be met in the selection of a landing site. Scientific and programmatic goals and objectives also help to define (3), the specific lander scientific payload requirements and capabilities. For example, what observations and experiments are required to address the major questions? How do we characterize the site in reference to the specific questions? Is mobility required and if so, how much? Which experiments are on the spacecraft, which on the rover? The results of these deliberations should lead to a surface exploration strategy, in which the goals and

  3. A Technical Guide to Ground-Water Model Selection at Sites Contaminated with Radioactive Substances

    EPA Pesticide Factsheets

    This report addresses the selection of ground-water flow and contaminant transport models and is intended to be used by hydrogeologists and geoscientists responsible for selecting transport models for use at sites containing radioactive materials.

  4. Attachment site selection of ticks on roe deer, Capreolus capreolus.

    PubMed

    Kiffner, C; Lödige, C; Alings, M; Vor, T; Rühe, F

    2011-01-01

    The spatio-temporal attachment site patterns of ticks feeding on their hosts can be of significance if co-feeding transmission (i.e. from tick to tick without a systemic infection of the host) of pathogens affects the persistence of a given disease. Using tick infestation data on roe deer, we analysed preferred attachment sites and niche width of Ixodes ticks (larvae, nymphs, males, females) and investigated the degree of inter- and intrastadial aggregation. The different development stages showed rather consistent attachment site patterns and relative narrow feeding site niches. Larvae were mostly found on the head and on the front legs of roe deer, nymphs reached highest densities on the head and highest adult densities were found on the neck of roe deer. The tick stages feeding (larvae, nymphs, females) on roe deer showed high degrees of intrastadial spatial aggregation, whereas males did not. Male ticks showed large feeding site overlap with female ticks. Feeding site overlap between larval-female and larval-nymphal ticks did occur especially during the months May-August on the head and front legs of roe deer and might allow pathogen transmission via co-feeding. Tick density, niche width and niche overlap on roe deer are mainly affected by seasonality, reflecting seasonal activity and abundance patterns of ticks. Since different tick development stages occur spatially and temporally clustered on roe deer, transmission experiments of tick-borne pathogens are urgently needed.

  5. 75 FR 39437 - Optimizing the Security of Biological Select Agents and Toxins in the United States

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-08

    ... Executive Order 13546--Optimizing the Security of Biological Select Agents and Toxins in the United States... July 2, 2010 Optimizing the Security of Biological Select Agents and Toxins in the United States By the... and productive scientific enterprise that utilizes biological select agents and toxins (BSAT)...

  6. Selection of Atmospheric Environmental Monitoring Sites based on Geographic Parameters Extraction of GIS and Fuzzy Matter-Element Analysis

    PubMed Central

    Wu, Jianfa; Peng, Dahao; Ma, Jianhao; Zhao, Li; Sun, Ce; Ling, Huanzhang

    2015-01-01

    To effectively monitor the atmospheric quality of small-scale areas, it is necessary to optimize the locations of the monitoring sites. This study combined geographic parameters extraction by GIS with fuzzy matter-element analysis. Geographic coordinates were extracted by GIS and transformed into rectangular coordinates. These coordinates were input into the Gaussian plume model to calculate the pollutant concentration at each site. Fuzzy matter-element analysis, which is used to solve incompatible problems, was used to select the locations of sites. The matter element matrices were established according to the concentration parameters. The comprehensive correlation functions KA (xj) and KB (xj), which reflect the degree of correlation among monitoring indices, were solved for each site, and a scatter diagram of the sites was drawn to determine the final positions of the sites based on the functions. The sites could be classified and ultimately selected by the scatter diagram. An actual case was tested, and the results showed that 5 positions can be used for monitoring, and the locations conformed to the technical standard. In the results of this paper, the hierarchical clustering method was used to improve the methods. The sites were classified into 5 types, and 7 locations were selected. Five of the 7 locations were completely identical to the sites determined by fuzzy matter-element analysis. The selections according to these two methods are similar, and these methods can be used in combination. In contrast to traditional methods, this study monitors the isolated point pollutant source within a small range, which can reduce the cost of monitoring. PMID:25923911

  7. Making the optimal decision in selecting protective clothing

    SciTech Connect

    Price, J. Mark

    2007-07-01

    Protective Clothing plays a major role in the decommissioning and operation of nuclear facilities. Literally thousands of employee dress-outs occur over the life of a decommissioning project and during outages at operational plants. In order to make the optimal decision on which type of protective clothing is best suited for the decommissioning or maintenance and repair work on radioactive systems, a number of interrelating factors must be considered, including - Protection; - Personnel Contamination; - Cost; - Radwaste; - Comfort; - Convenience; - Logistics/Rad Material Considerations; - Reject Rate of Laundered Clothing; - Durability; - Security; - Personnel Safety including Heat Stress; - Disposition of Gloves and Booties. In addition, over the last several years there has been a trend of nuclear power plants either running trials or switching to Single Use Protective Clothing (SUPC) from traditional protective clothing. In some cases, after trial usage of SUPC, plants have chosen not to switch. In other cases after switching to SUPC for a period of time, some plants have chosen to switch back to laundering. Based on these observations, this paper reviews the 'real' drivers, issues, and interrelating factors regarding the selection and use of protective clothing throughout the nuclear industry. (authors)

  8. Remedial action selection report Maybell, Colorado, site. Final report

    SciTech Connect

    1996-12-01

    The Maybell uranium mill tailings site is 25 miles (mi) (40 kilometers [km]) west of the town of Craig, Colorado, in Moffat County, in the northwestern part of the state. The unincorporated town of Maybell is 5 road mi (8 km) southwest of the site. The site is 2.5 mi (4 km) northeast of the Yampa River on relatively flat terrain broken by low, flat-topped mesas. U.S. Highway 40 runs east-west 2 mi (3.2 km) south of the site. The designated site covers approximately 110 acres (ac) (45 hectares [ha]) and consists of a concave-shaped tailings pile and rubble from the demolition of the mill buildings buried in the former mill area. The site is situated between Johnson Wash to the east and Rob Pit Mine to the west. Numerous reclaimed and unreclaimed mines are in the immediate vicinity. Aerial photographs (included at the end of this executive summary) show evidence of mining activity around the Maybell site. Contaminated materials at the Maybell processing site include the tailings pile, which has an average depth of 20 feet (ft) (6 meters [ml]) and contains 2.8 million cubic yards (yd{sup 3}) (2.1 million cubic meters [m{sup 3}]) of tailings. The former mill processing area is on the north side of the site and contains 20,000 yd 3 (15,000 m{sup 3}) of contaminated demolition debris. Off-pile contamination is present and includes areas adjacent to the tailings pile, as well as contamination dispersed by wind and surface water flow. The volume of off-pile contamination to be placed in the disposal cell is 550,000 yd{sup 3}(420,000 m{sup 3}). The total volume of contaminated materials to be disposed of as part of the remedial action is estimated to be 3.37 million yd{sup 3} (2.58 million m{sup 3}).

  9. Site-specific PEGylation of therapeutic proteins via optimization of both accessible reactive amino acid residues and PEG derivatives.

    PubMed

    Zhang, Chun; Yang, Xiao-lan; Yuan, Yong-hua; Pu, Jun; Liao, Fei

    2012-08-01

    Modification of accessible amino acid residues with poly(ethylene glycol) [PEG] is a widely used technique for formulating therapeutic proteins. In practice, site-specific PEGylation of all selected/engineered accessible nonessential reactive residues of therapeutic proteins with common activated PEG derivatives is a promising strategy to concomitantly improve pharmacokinetics, allow retention of activity, alleviate immunogenicity, and avoid modification isomers. Specifically, through molecular engineering of a therapeutic protein, accessible essential residues reactive to an activated PEG derivative are substituted with unreactive residues provided that protein activity is retained, and a limited number of accessible nonessential reactive residues with optimized distributions are selected/introduced. Subsequently, all accessible nonessential reactive residues are completely PEGylated with the activated PEG derivative in great excess. Branched PEG derivatives containing new PEG chains with negligible metabolic toxicity are more desirable for site-specific PEGylation. Accordingly, for the successful formulation of therapeutic proteins, optimization of the number and distributions of accessible nonessential reactive residues via molecular engineering can be integrated with the design of large-sized PEG derivatives to achieve site-specific PEGylation of all selected/engineered accessible reactive residues.

  10. Hydrogen Oxidation-Selective Electrocatalysis by Fine Tuning of Pt Ensemble Sites to Enhance the Durability of Automotive Fuel Cells.

    PubMed

    Yun, Su-Won; Park, Shin-Ae; Kim, Tae-June; Kim, Jun-Hyuk; Pak, Gi-Woong; Kim, Yong-Tae

    2017-02-08

    A simple, inexpensive approach is proposed for enhancing the durability of automotive proton exchange membrane fuel cells by selective promotion of the hydrogen oxidation reaction (HOR) and suppression of the oxygen reduction reaction (ORR) at the anode in startup/shutdown events. Dodecanethiol forms a self-assembled monolayer (SAM) on the surface of Pt particles, thus decreasing the number of Pt ensemble sites. Interestingly, by controlling the dodecanethiol concentration during SAM formation, the number of ensemble sites can be precisely optimized such that it is sufficient for the HOR but insufficient for the ORR. Thus, a Pt surface with an SAM of dodecanethiol clearly effects HOR-selective electrocatalysis. Clear HOR selectivity is demonstrated in unit cell tests with the actual membrane electrode assembly, as well as in an electrochemical three-electrode setup with a thin-film rotating disk electrode configuration.

  11. Reference site selection report for the advanced liquid metal reactor at the Idaho National Engineering Laboratory

    SciTech Connect

    Sivill, R.L.

    1990-03-01

    This Reference Site Selection Report was prepared by EG G, Idaho Inc., for General Electric (GE) to provide information for use by the Department of Energy (DOE) in selecting a Safety Test Site for an Advanced Liquid Metal Reactor. Similar Evaluation studies are planned to be conducted at other potential DOE sites. The Power Reactor Innovative Small Module (PRISM) Concept was developed for ALMR by GE. A ALMR Safety Test is planned to be performed on a DOE site to demonstrate features and meet Nuclear Regulatory Commission Requirements. This study considered possible locations at the Idaho National Engineering Laboratory that met the ALMR Prototype Site Selection Methodology and Criteria. Four sites were identified, after further evaluation one site was eliminated. Each of the remaining three sites satisfied the criteria and was graded. The results were relatively close. Thus concluding that the Idaho National Engineering Laboratory is a suitable location for an Advanced Liquid Metal Reactor Safety Test. 23 refs., 13 figs., 9 tabs.

  12. Site-directed alkylation of multiple opioid receptors. I. Binding selectivity

    SciTech Connect

    James, I.F.; Goldstein, A.

    1984-05-01

    A method for measuring and expressing the binding selectivity of ligands for mu, delta, and kappa opioid binding sites is reported. Radioligands are used that are partially selective for these sites in combination with membrane preparations enriched in each site. Enrichment was obtained by treatment of membranes with the alkylating agent beta-chlornaltrexamine in the presence of appropriate protecting ligands. After enrichment for mu receptors, (/sup 3/H) dihydromorphine bound to a single type of site as judged by the slope of competition binding curves. After enrichment for delta or kappa receptors, binding sites for (/sup 3/H) (D-Ala2, D-Leu5)enkephalin and (3H)ethylketocyclazocine, respectively, were still not homogeneous. There were residual mu sites in delta-enriched membranes but no evidence for residual mu or delta sites in kappa-enriched membranes were found. This method was used to identify ligands that are highly selective for each of the three types of sites.

  13. Rocky Mountain Snowpack Chemistry at Selected Sites, 2004

    USGS Publications Warehouse

    Ingersoll, George P.; Mast, M. Alisa; Nanus, Leora; Handran, Heather H.; Manthorne, David J.; Hultstrand, Douglas M.

    2007-01-01

    During spring 2004, the U.S. Geological Survey in cooperation with the National Park Service and the U.S. Department of Agriculture, Forest Service collected and analyzed snowpack samples for 65 sites in the Rocky Mountain region from New Mexico to Montana. Snowpacks were sampled from late February through early April and generally had well-below-average- to near-average snow-water equivalent. Regionally, on April 1, snow-water equivalent ranged from 50 to 89 percent. At most regional sites monitored during 1993-2004, snowpack ammonium, nitrate, and sulfate concentrations for 2004 were lower than the 12-year averages. Snowpack ammonium concentrations in the region were lower than average concentrations for the period at 61 percent of sites in the region, but showed a new pattern compared to previous years with three of the four highest 2004 concentrations observed in northern Colorado. Nitrate concentrations in 2004 were lower than the 12-year average for the year at 53 percent of regional sites, and typically occurred at sites in Wyoming, Idaho, and Montana where powerplants and large industrial areas were limited. A regional decrease in sulfate concentrations across most of the Rocky Mountains (with concentrations lower than the 12-year average at 84 percent of snowpack sites) was consistent with other monitoring of atmospheric deposition in the Western United States. Total mercury concentrations, although data are only available for the past 3 years, decreased slightly for the region as a whole in 2004 relative to 2003. Ratios of stable sulfur isotopes indicated a similar regional pattern as observed in recent years with sulfur-34 (d34S) values generally increasing northward from northern New Mexico and southern Colorado to northern Colorado, Wyoming, Idaho, and Montana.

  14. Optimal-adaptive filters for modelling spectral shape, site amplification, and source scaling

    USGS Publications Warehouse

    Safak, Erdal

    1989-01-01

    This paper introduces some applications of optimal filtering techniques to earthquake engineering by using the so-called ARMAX models. Three applications are presented: (a) spectral modelling of ground accelerations, (b) site amplification (i.e., the relationship between two records obtained at different sites during an earthquake), and (c) source scaling (i.e., the relationship between two records obtained at a site during two different earthquakes). A numerical example for each application is presented by using recorded ground motions. The results show that the optimal filtering techniques provide elegant solutions to above problems, and can be a useful tool in earthquake engineering.

  15. 24 CFR 983.57 - Site selection standards.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... private sanitary water supply for the site, approved in accordance with law, may be considered adequate..., recreational, educational, commercial, and health facilities and services and other municipal facilities and... experiencing significant private investment that is demonstrably improving the economic character of the...

  16. Off-Site Trip Leaders: Selecting Appropriate Staff.

    ERIC Educational Resources Information Center

    Evans, Will

    1996-01-01

    Well-trained off-site trip leaders can turn a trip into a positive educational lesson. American Camping Association standards are referenced, and some personality traits are suggested as criteria for determining the suitability of staff to act responsibly "in loco director." Discusses factors that determine counselor-to-camper ratios,…

  17. 15 CFR 921.11 - Site selection and feasibility.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... and II); (2) The site's ecological characteristics, including its biological productivity, diversity... natural system to approximate an ecological unit and to ensure effective conservation. Boundary size will... areas (or “core area”) and a buffer zone. Key land and water areas and a buffer zone will likely...

  18. 15 CFR 921.11 - Site selection and feasibility.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... and II); (2) The site's ecological characteristics, including its biological productivity, diversity... natural system to approximate an ecological unit and to ensure effective conservation. Boundary size will... areas (or “core area”) and a buffer zone. Key land and water areas and a buffer zone will likely...

  19. 15 CFR 921.11 - Site selection and feasibility.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... and II); (2) The site's ecological characteristics, including its biological productivity, diversity... natural system to approximate an ecological unit and to ensure effective conservation. Boundary size will... areas (or “core area”) and a buffer zone. Key land and water areas and a buffer zone will likely...

  20. 15 CFR 921.11 - Site selection and feasibility.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... and II); (2) The site's ecological characteristics, including its biological productivity, diversity... natural system to approximate an ecological unit and to ensure effective conservation. Boundary size will... areas (or “core area”) and a buffer zone. Key land and water areas and a buffer zone will likely...

  1. 15 CFR 921.11 - Site selection and feasibility.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... and II); (2) The site's ecological characteristics, including its biological productivity, diversity... natural system to approximate an ecological unit and to ensure effective conservation. Boundary size will... areas (or “core area”) and a buffer zone. Key land and water areas and a buffer zone will likely...

  2. A Simple Method for Improving Torsion Optimization of Ligand Molecules in Receptor Binding Sites.

    PubMed

    Che, Jianwei

    2005-07-01

    A simple but effective method is introduced for optimizing ligand molecules in torsion space within receptor binding sites. The algorithm makes use of geometric constraints of ligand molecules to search for energetically favorable conformations. It is applied to a conjugate gradient (CG) method as an example. During conformational energy optimization, new line search directions are modified according to the spatial span of rotational groups in ligand molecules. Significant improvements were observed in terms of the abilities both to recover global optimal structures and to obtain lower energy ensembles. This simple algorithm allows rapid implementation and can be incorporated into other conformational energy optimization techniques.

  3. THE ROLE OF GIS IN SELECTING SITES FOR RIPARIAN RESTORATION BASED ON HYDROLOGY AND LAND USE

    EPA Science Inventory

    Successful long-term wetland restoration efforts require consideration of hydrology and surrounding land use during the site selection process. This article describes an approach to initial site selection in the San Luis Rey River watershed in southern California that uses waters...

  4. Application of an Optimal Search Strategy for the DNAPL Source Identification to a Field Site in Nanjing, China

    NASA Astrophysics Data System (ADS)

    Longting, M.; Ye, S.; Wu, J.

    2014-12-01

    Identification and removing the DNAPL source in aquifer system is vital in rendering remediation successful and lowering the remediation time and cost. Our work is to apply an optimal search strategy introduced by Zoi and Pinder[1], with some modifications, to a field site in Nanjing City, China to define the strength, and location of DNAPL sources using the least samples. The overall strategy uses Monte Carlo stochastic groundwater flow and transport modeling, incorporates existing sampling data into the search strategy, and determines optimal sampling locations that are selected according to the reduction in overall uncertainty of the field and the proximity to the source locations. After a sample is taken, the plume is updated using a Kalman filter. The updated plume is then compared to the concentration fields that emanate from each individual potential source using fuzzy set technique. The comparison followed provides weights that reflect the degree of truth regarding the location of the source. The above steps are repeated until the optimal source characteristics are determined. Considering our site case, some specific modifications and work have been done as follows. K random fields are generated after fitting the measurement K data to the variogram model. The locations of potential sources that are given initial weights are targeted based on the field survey, with multiple potential source locations around the workshops and wastewater basin. Considering the short history (1999-2010) of manufacturing optical brightener PF at the site, and the existing sampling data, a preliminary source strength is then estimated, which will be optimized by simplex method or GA later. The whole algorithm then will guide us for optimal sampling and update as the investigation proceeds, until the weights finally stabilized. Reference [1] Dokou Zoi, and George F. Pinder. "Optimal search strategy for the definition of a DNAPL source." Journal of Hydrology 376.3 (2009): 542

  5. Site-selective electronic correlation in α-plutonium metal.

    PubMed

    Zhu, Jian-Xin; Albers, R C; Haule, K; Kotliar, G; Wills, J M

    2013-01-01

    An understanding of the phase diagram of elemental plutonium (Pu) must include both, the effects of the strong directional bonding and the high density of states of the Pu 5f electrons, as well as how that bonding weakens under the influence of strong electronic correlations. Here we present electronic-structure calculations of the full 16-atom per unit cell α-phase structure within the framework of density functional theory together with dynamical mean-field theory. Our calculations demonstrate that Pu atoms sitting on different sites within the α-Pu crystal structure have a strongly varying site dependence of the localization-delocalization correlation effects of their 5f electrons and a corresponding effect on the bonding and electronic properties of this complicated metal. In short, α-Pu has the capacity to simultaneously have multiple degrees of electron localization/delocalization of Pu 5f electrons within a pure single-element material.

  6. Scour at selected bridge sites in Alabama, 1991-94

    USGS Publications Warehouse

    Atkins, J. Brian; Hedgecock, T. Scott

    1996-01-01

    Scour data were collected at 15 sites on streams in Alabama during high flow conditions. The recurrence intervals of the streamflows ranged from less than 2 to 10 years. Scour depths measured near bridge piers ranged from 0.3 to 5.8 feet. The Colorado State University (CSU) local scour equation recommended in the Federal Highway Administration Hydraulic Engineering Circular No. 18 was used to estimate scour depths at the study sites. Estimated scour depths based on the CSU equation ranged from 2.5 to 12.7 feet with residuals (measured scour depth minus estimated scour depth) ranging from -8.1 to -1.4 feet. A comparison of the residuals with the estimated scour depths indicated that the CSU equation overestimated the measured scour depths throughout the range of measured data by an average of 434 percent.

  7. Characterization of Seismic Noise at Selected Non-Urban Sites

    DTIC Science & Technology

    2010-03-01

    Hz center frequency for vertical, east-west and north-south components of wind farm ground motion during the 50-min periods 0000 - 0050 (turbines...13 Figure 6. Hourly power PDFs at 4-Hz center frequency for vertical ground motion for the period 0400 – 1200 GMT...15 Figure 7. Wind speed data recorded at the Enfield site. Data dropouts occurred during the 10-min periods

  8. Reassessment of selected factors affecting siting of Nuclear Power Plants

    SciTech Connect

    Davis, R.E.; Hanson, A.L.; Mubayi, V.; Nourbakhsh, H.P.

    1997-02-01

    Brookhaven National Laboratory has performed a series of probabilistic consequence assessment calculations for nuclear reactor siting. This study takes into account recent insights into severe accident source terms and examines consequences in a risk based format consistent with the quantitative health objectives (QHOs) of the NRC`s Safety Goal Policy. Simplified severe accident source terms developed in this study are based on the risk insights of NUREG-1150. The results of the study indicate that both the quantity of radioactivity released in a severe accident as well as the likelihood of a release are lower than those predicted in earlier studies. The accident risks using the simplified source terms are examined at a series of generic plant sites, that vary in population distribution, meteorological conditions, and exclusion area boundary distances. Sensitivity calculations are performed to evaluate the effects of emergency protective action assumptions on the risk of prompt fatality and latent cancers fatality, and population relocation. The study finds that based on the new source terms the prompt and latent fatality risks at all generic sites meet the QHOs of the NRC`s Safety Goal Policy by margins ranging from one to more than three orders of magnitude. 4 refs., 17 figs., 24 tabs.

  9. Nuclear facility decommissioning and site remedial actions: a selected bibliography

    SciTech Connect

    Owen, P.T.; Knox, N.P.; Fielden, J.M.; Johnson, C.A.

    1982-09-01

    This bibliography contains 693 references with abstracts on the subject of nuclear facility decommissioning, uranium mill tailings management, and site remedial actions. Foreign, as well as domestic, literature of all types - technical reports, progress reports, journal articles, conference papers, symposium proceedings, theses, books, patents, legislation, and research project descriptions - has been included in this publication. The bibliography contains scientific (basic research as well as applied technology), economic, regulatory, and legal literature pertinent to the US Department of Energy's Remedial Action Program. Major chapters are Surplus Facilities Management Program, Nuclear Facilities Decommissioning, Formerly Utilized Sites Remedial Action Program, Uranium Mill Tailings Remedial Action Program, Grand Junction Remedial Action Program, and Uranium Mill Tailings Management. Chapter sections for chapters 1 and 2 include: Design, Planning, and Regulations; Site Surveys; Decontamination Studies; Dismantlement and Demolition; Land Decontamination and Reclamation; Waste Disposal; and General Studies. The references within each chapter are arranged alphabetically by leading author. References having no individual author are arranged by corporate author or by title. Indexes are provided for (1) author; (2) corporate affiliation; (3) title; (4) publication description; (5) geographic location; and (6) keywords. An appendix of 202 bibliographic references without abstracts or indexes has been included in this bibliography. This appendix represents literature identified but not abstracted due to time constraints.

  10. Specification of sites for polarized growth in Saccharomyces cerevisiae and the influence of external factors on site selection.

    PubMed Central

    Madden, K; Snyder, M

    1992-01-01

    Many eucaryotic cell types exhibit polarized cell growth and polarized cell division at nonrandom sites. The sites of polarized growth were investigated in G1 arrested haploid Saccharomyces cerevisiae cells. When yeast cells are arrested during G1 either by treatment with alpha-factor or by shifting temperature-sensitive cdc28-1 cells to the restrictive temperature, the cells form a projection. Staining with Calcofluor reveals that in both cases the projection usually forms at axial sites (i.e., next to the previous bud scar); these are the same sites where bud formation is expected to occur. These results indicate that sites of polarized growth are specified before the end of G1. Sites of polarized growth can be influenced by external conditions. Cells grown to stationary phase and diluted into fresh medium preferentially select sites for polarized growth opposite the previous bud scar (i.e., distal sites). Incubation of cells in a mating mixture results in projection formation at nonaxial sites: presumably cells form projections toward their mating partner. These observations have important implications in understanding three aspects of cell polarity in yeast: 1) how yeast cell shape is influenced by growth conditions 2) how sites of polarized growth are chosen, and 3) the pathway by which polarity is affected and redirected during the mating process. Images PMID:1421575

  11. Nesting habitat and nest site selection by the bald eagle in Maryland. Final report

    SciTech Connect

    Mosher, J.A.; Andrew, J.M.

    1981-07-01

    Habitat at 70 bald eagle (Haliaeetus leucocephalus) nest sites was quantified and compared with evaluations at 139 random habitat plots located in the Chesapeake Bay region of Maryland. Bald eagles selected vegetationally open habitats near water and away from selected human activities relative to random habitat plots. Successful nest sites were located in denser forest stands farther from water and unoccupied structures than unsuccessful nest sites.

  12. The Importance of Site Selection for Radio Astronomy

    NASA Astrophysics Data System (ADS)

    Umar, Roslan; Zainal Abidin, Zamri; Abidin Ibrahim, Zainol

    2014-10-01

    Radio sources are very weak since this object travel very far from outer space. Radio astronomy studies are limited due to radio frequency interference (RFI) that is made by man. If the harassment is not stopped, it will provide critical problems in their radio astronomy scientists research. The purpose of this study is to provide RFI map Peninsular Malaysia with a minimum mapping techniques RFI interference. RFI mapping technique using GIS is proposed as a tool in mapping techniques. Decision-making process for the selection requires gathering information from a variety of parameters. These factors affecting the selection process are also taken account. In this study, various factors or parameters involved such as availability of telecommunications transmission (including radio and television), rainfall, water line and human activity. This study will benefit radio astronomy research especially in the RFI profile in Malaysia. Keywords: Radio Astronomy, Radio Frequency Interference (RFI), RFI mapping technique : GIS.

  13. Residual herbicide study on selected Hanford Site roadsides

    SciTech Connect

    Smith, J.L.; Kemp, C.J.; Sackschewsky, M.R.

    1993-08-01

    Westinghouse Hanford Company routinely treats roadsides with herbicides to control undesirable plant growth. An experiment was conducted to test perennial grass germination in soils adjacent to roadways of the Hanford Site. The primary variable was the distance from the roadside. A simple germination test was executed in a controlled-environment chamber to determine the residual effects of these applications. As expected, the greatest herbicide activity was found directly adjacent to the roadway, approximately 0 to 20 ft (0 to 6.3 m) from the roadway.

  14. Bed site selection by neonate deer in grassland habitats on the northern Great Plains

    USGS Publications Warehouse

    Grovenburg, T.W.; Jacques, C.N.; Klaver, R.W.; Jenks, J.A.

    2010-01-01

    Bed site selection is an important behavioral trait influencing neonate survival. Vegetation characteristics of bed sites influence thermal protection of neonates and concealment from predators. Although previous studies describe bed site selection of neonatal white-tailed deer (Odocoileus virginianus) in regions of forested cover, none determined microhabitat effects on neonate bed site selection in the Northern Great Plains, an area of limited forest cover. During summers 2007–2009, we investigated bed site selection (n  =  152) by 81 radiocollared neonate white-tailed deer in north-central South Dakota, USA. We documented 80 (52.6%) bed sites in tallgrass–Conservation Reserve Program lands, 35 (23.0%) bed sites in forested cover, and 37 (24.3%) in other habitats (e.g., pasture, alfalfa, wheat). Bed site selection varied with age and sex of neonate. Tree canopy cover (P < 0.001) and tree basal area (P < 0.001) decreased with age of neonates, with no bed sites observed in forested cover after 18 days of age. Male neonates selected sites with less grass cover (P < 0.001), vertical height of understory vegetation (P < 0.001), and density of understory vegetation (P < 0.001) but greater bare ground (P  =  0.047), litter (P  =  0.028), and wheat (P  =  0.044) than did females. Odds of bed site selection increased 3.5% (odds ratio  =  1.035, 95% CI  =  1.008–1.062) for every 1-cm increase in vertical height of understory vegetation. Management for habitat throughout the grasslands of South Dakota that maximizes vertical height of understory vegetation would enhance cover characteristics selected by neonates.

  15. Enzymatic Detoxication, Conformational Selection, and the Role of Molten Globule Active Sites*

    PubMed Central

    Honaker, Matthew T.; Acchione, Mauro; Zhang, Wei; Mannervik, Bengt; Atkins, William M.

    2013-01-01

    The role of conformational ensembles in enzymatic reactions remains unclear. Discussion concerning “induced fit” versus “conformational selection” has, however, ignored detoxication enzymes, which exhibit catalytic promiscuity. These enzymes dominate drug metabolism and determine drug-drug interactions. The detoxication enzyme glutathione transferase A1–1 (GSTA1–1), exploits a molten globule-like active site to achieve remarkable catalytic promiscuity wherein the substrate-free conformational ensemble is broad with barrierless transitions between states. A quantitative index of catalytic promiscuity is used to compare engineered variants of GSTA1–1 and the catalytic promiscuity correlates strongly with characteristics of the thermodynamic partition function, for the substrate-free enzymes. Access to chemically disparate transition states is encoded by the substrate-free conformational ensemble. Pre-steady state catalytic data confirm an extension of the conformational selection model, wherein different substrates select different starting conformations. The kinetic liability of the conformational breadth is minimized by a smooth landscape. We propose that “local” molten globule behavior optimizes detoxication enzymes. PMID:23649628

  16. Site selection for the future stations of the french permanent broadband network

    NASA Astrophysics Data System (ADS)

    Vergne, Jérôme; Charade, Olivier

    2013-04-01

    RESIF (REseau SIsmologique et géodésique Français) is a new French research infrastructure dedicated to the observation of earth deformation based on seismic and geodetic instruments mainly located in France. One of its major component, called RESIF-CLB (Construction Large Bande), is devoted to the evolution of the permanent seismic broadband network in metropolitan France with the objective to complement the 45 existing stations with ~155 new stations within the next eight years. This network will be used for various scientific objectives including deep structures imaging and national seismicity monitoring. The chosen network topology consists in a backbone of homogeneously distributed stations (long wavelength array) completed by additional stations in seismically active regions. Management of the RESIF-CLB project is carried out by the technical division of INSU (Institut National des Sciences de l'Univers) who will rely on eight regional observatories and the CEA-LDG for the construction and operation of the stations. To optimize the performance of the network, we put a strong emphasis on the standardization of the stations in term of vault types, scientific and technical instrumentation and operation procedures. We also set up a procedure for site selection requiring that every potential site has to be tested for at least 3 weeks with a minimalist installation. Analysis of the continuous ambient noise records is then included in a standardized report submitted to all committed partners for acceptance. During the last two years, about 60 potential new sites have been tested, spanning various places and environments. We present a review of the seismic noise measurements at these sites and discuss the influence of different types of noise sources depending on the frequency band of interest. For example, we show that regional population distribution can be used as a proxy to infer the noise level at frequencies higher than 1 Hz. Based on similar noise analyses

  17. Reliable Refuge: Two Sky Island Scorpion Species Select Larger, Thermally Stable Retreat Sites.

    PubMed

    Becker, Jamie E; Brown, Christopher A

    2016-01-01

    Sky island scorpions shelter under rocks and other surface debris, but, as with other scorpions, it is unclear whether these species select retreat sites randomly. Furthermore, little is known about the thermal preferences of scorpions, and no research has been done to identify whether reproductive condition might influence retreat site selection. The objectives were to (1) identify physical or thermal characteristics for retreat sites occupied by two sky island scorpions (Vaejovis cashi Graham 2007 and V. electrum Hughes 2011) and those not occupied; (2) determine whether retreat site selection differs between the two study species; and (3) identify whether thermal selection differs between species and between gravid and non-gravid females of the same species. Within each scorpion's habitat, maximum dimensions of rocks along a transect line were measured and compared to occupied rocks to determine whether retreat site selection occurred randomly. Temperature loggers were placed under a subset of occupied and unoccupied rocks for 48 hours to compare the thermal characteristics of these rocks. Thermal gradient trials were conducted before parturition and after dispersal of young in order to identify whether gravidity influences thermal preference. Vaejovis cashi and V. electrum both selected larger retreat sites that had more stable thermal profiles. Neither species appeared to have thermal preferences influenced by reproductive condition. However, while thermal selection did not differ among non-gravid individuals, gravid V. electrum selected warmer temperatures than its gravid congener. Sky island scorpions appear to select large retreat sites to maintain thermal stability, although biotic factors (e.g., competition) could also be involved in this choice. Future studies should focus on identifying the various biotic or abiotic factors that could influence retreat site selection in scorpions, as well as determining whether reproductive condition affects thermal

  18. Reliable Refuge: Two Sky Island Scorpion Species Select Larger, Thermally Stable Retreat Sites

    PubMed Central

    Becker, Jamie E.; Brown, Christopher A.

    2016-01-01

    Sky island scorpions shelter under rocks and other surface debris, but, as with other scorpions, it is unclear whether these species select retreat sites randomly. Furthermore, little is known about the thermal preferences of scorpions, and no research has been done to identify whether reproductive condition might influence retreat site selection. The objectives were to (1) identify physical or thermal characteristics for retreat sites occupied by two sky island scorpions (Vaejovis cashi Graham 2007 and V. electrum Hughes 2011) and those not occupied; (2) determine whether retreat site selection differs between the two study species; and (3) identify whether thermal selection differs between species and between gravid and non-gravid females of the same species. Within each scorpion’s habitat, maximum dimensions of rocks along a transect line were measured and compared to occupied rocks to determine whether retreat site selection occurred randomly. Temperature loggers were placed under a subset of occupied and unoccupied rocks for 48 hours to compare the thermal characteristics of these rocks. Thermal gradient trials were conducted before parturition and after dispersal of young in order to identify whether gravidity influences thermal preference. Vaejovis cashi and V. electrum both selected larger retreat sites that had more stable thermal profiles. Neither species appeared to have thermal preferences influenced by reproductive condition. However, while thermal selection did not differ among non-gravid individuals, gravid V. electrum selected warmer temperatures than its gravid congener. Sky island scorpions appear to select large retreat sites to maintain thermal stability, although biotic factors (e.g., competition) could also be involved in this choice. Future studies should focus on identifying the various biotic or abiotic factors that could influence retreat site selection in scorpions, as well as determining whether reproductive condition affects thermal

  19. To Eat or Not to Eat: An Easy Simulation of Optimal Diet Selection in the Classroom

    ERIC Educational Resources Information Center

    Ray, Darrell L.

    2010-01-01

    Optimal diet selection, a component of optimal foraging theory, suggests that animals should select a diet that either maximizes energy or nutrient consumption per unit time or minimizes the foraging time needed to attain required energy or nutrients. In this exercise, students simulate the behavior of foragers that either show no foraging…

  20. Comparison of Genetic Algorithm, Particle Swarm Optimization and Biogeography-based Optimization for Feature Selection to Classify Clusters of Microcalcifications

    NASA Astrophysics Data System (ADS)

    Khehra, Baljit Singh; Pharwaha, Amar Partap Singh

    2016-06-01

    Ductal carcinoma in situ (DCIS) is one type of breast cancer. Clusters of microcalcifications (MCCs) are symptoms of DCIS that are recognized by mammography. Selection of robust features vector is the process of selecting an optimal subset of features from a large number of available features in a given problem domain after the feature extraction and before any classification scheme. Feature selection reduces the feature space that improves the performance of classifier and decreases the computational burden imposed by using many features on classifier. Selection of an optimal subset of features from a large number of available features in a given problem domain is a difficult search problem. For n features, the total numbers of possible subsets of features are 2n. Thus, selection of an optimal subset of features problem belongs to the category of NP-hard problems. In this paper, an attempt is made to find the optimal subset of MCCs features from all possible subsets of features using genetic algorithm (GA), particle swarm optimization (PSO) and biogeography-based optimization (BBO). For simulation, a total of 380 benign and malignant MCCs samples have been selected from mammogram images of DDSM database. A total of 50 features extracted from benign and malignant MCCs samples are used in this study. In these algorithms, fitness function is correct classification rate of classifier. Support vector machine is used as a classifier. From experimental results, it is also observed that the performance of PSO-based and BBO-based algorithms to select an optimal subset of features for classifying MCCs as benign or malignant is better as compared to GA-based algorithm.

  1. Landfill site selection using combination of GIS and fuzzy AHP, a case study: Iranshahr, Iran.

    PubMed

    Torabi-Kaveh, M; Babazadeh, R; Mohammadi, S D; Zaresefat, M

    2016-03-09

    One of the most important recent challenges in solid waste management throughout the world is site selection of sanitary landfill. Commonly, because of simultaneous effects of social, environmental, and technical parameters on suitability of a landfill site, landfill site selection is a complex process and depends on several criteria and regulations. This study develops a multi-criteria decision analysis (MCDA) process, which combines geographic information system (GIS) analysis with a fuzzy analytical hierarchy process (FAHP), to determine suitable sites for landfill construction in Iranshahr County, Iran. The GIS was used to calculate and classify selected criteria and FAHP was used to assess the criteria weights based on their effectiveness on selection of potential landfill sites. Finally, a suitability map was prepared by overlay analyses and suitable areas were identified. Four suitability classes within the study area were separated, including high, medium, low, and very low suitability areas, which represented 18%, 15%, 55%, and 12% of the study area, respectively.

  2. Modeling Training Site Vegetation Coverage Probability with a Random Optimizing Procedure: An Artificial Neural Network Approach.

    DTIC Science & Technology

    1998-05-01

    Coverage Probability with a Random Optimization Procedure: An Artificial Neural Network Approach by Biing T. Guan, George Z. Gertner, and Alan B...Modeling Training Site Vegetation Coverage Probability with a Random Optimizing Procedure: An Artificial Neural Network Approach 6. AUTHOR(S) Biing...coverage based on past coverage. Approach A literature survey was conducted to identify artificial neural network analysis techniques applicable for

  3. Threshold Assessment: Definition of Acceptable Sites as Part of Site Selection for the Japanese HLW Program

    SciTech Connect

    McKenna, S.A.; Wakasugi, Keiichiro; Webb, E.K.; Makino, Hitoshi; Ishihara, Yoshinao, Ijiri, Yuji; Sawada, Atsushi; Baba, Tomoko; Ishiguro, Katsuhiko; Umeki, Hiroyuki

    2000-10-03

    For the last ten years, the Japanese High-Level Nuclear Waste (HLW) repository program has focused on assessing the feasibility of a basic repository concept, which resulted in the recently published H12 Report. As Japan enters the implementation phase, a new organization must identify, screen and choose potential repository sites. Thus, a rapid mechanism for determining the likelihood of site suitability is critical. The threshold approach, described here, is a simple mechanism for defining the likelihood that a site is suitable given estimates of several critical parameters. We rely on the results of a companion paper, which described a probabilistic performance assessment simulation of the HLW reference case in the H12 report. The most critical two or three input parameters are plotted against each other and treated as spatial variables. Geostatistics is used to interpret the spatial correlation, which in turn is used to simulate multiple realizations of the parameter value maps. By combining an array of realizations, we can look at the probability that a given site, as represented by estimates of this combination of parameters, would be good host for a repository site.

  4. An artificial system for selecting the optimal surgical team.

    PubMed

    Saberi, Nahid; Mahvash, Mohsen; Zenati, Marco

    2015-01-01

    We introduce an intelligent system to optimize a team composition based on the team's historical outcomes and apply this system to compose a surgical team. The system relies on a record of the procedures performed in the past. The optimal team composition is the one with the lowest probability of unfavorable outcome. We use the theory of probability and the inclusion exclusion principle to model the probability of team outcome for a given composition. A probability value is assigned to each person of database and the probability of a team composition is calculated from them. The model allows to determine the probability of all possible team compositions even if there is no recoded procedure for some team compositions. From an analytical perspective, assembling an optimal team is equivalent to minimizing the overlap of team members who have a recurring tendency to be involved with procedures of unfavorable results. A conceptual example shows the accuracy of the proposed system on obtaining the optimal team.

  5. Age-Related Differences in Goals: Testing Predictions from Selection, Optimization, and Compensation Theory and Socioemotional Selectivity Theory

    ERIC Educational Resources Information Center

    Penningroth, Suzanna L.; Scott, Walter D.

    2012-01-01

    Two prominent theories of lifespan development, socioemotional selectivity theory and selection, optimization, and compensation theory, make similar predictions for differences in the goal representations of younger and older adults. Our purpose was to test whether the goals of younger and older adults differed in ways predicted by these two…

  6. Using Fisher Information Criteria for Chemical Sensor Selection via Convex Optimization Methods

    DTIC Science & Technology

    2016-11-16

    best sensors after an optimization procedure. Due to the positive definite nature of the Fisher information matrix, convex optimization may be used to...parametrized to select the best sensors after an optimization procedure. Due to the positive definite nature of the Fisher information matrix, convex op...Naval Research Laboratory Washington, DC 20375-5320 NRL/MR/6180--16-9711 Using Fisher Information Criteria for Chemical Sensor Selection via Convex

  7. Polyhedral Interpolation for Optimal Reaction Control System Jet Selection

    NASA Technical Reports Server (NTRS)

    Gefert, Leon P.; Wright, Theodore

    2014-01-01

    An efficient algorithm is described for interpolating optimal values for spacecraft Reaction Control System jet firing duty cycles. The algorithm uses the symmetrical geometry of the optimal solution to reduce the number of calculations and data storage requirements to a level that enables implementation on the small real time flight control systems used in spacecraft. The process minimizes acceleration direction errors, maximizes control authority, and minimizes fuel consumption.

  8. Site Selection in Experiments: An Assessment of Site Recruitment and Generalizability in Two Scale-Up Studies

    ERIC Educational Resources Information Center

    Tipton, Elizabeth; Fellers, Lauren; Caverly, Sarah; Vaden-Kiernan, Michael; Borman, Geoffrey; Sullivan, Kate; Ruiz de Castilla, Veronica

    2016-01-01

    Recently, statisticians have begun developing methods to improve the generalizability of results from large-scale experiments in education. This work has included the development of methods for improved site selection when random sampling is infeasible, including the use of stratification and targeted recruitment strategies. This article provides…

  9. Model-data fusion across ecosystems: from multi-site optimizations to global simulations

    NASA Astrophysics Data System (ADS)

    Kuppel, S.; Peylin, P.; Maignan, F.; Chevallier, F.; Kiely, G.; Montagnani, L.; Cescatti, A.

    2014-05-01

    This study uses a variational data assimilation framework to simultaneously constrain a global ecosystem model with eddy covariance measurements of daily net carbon (NEE) and latent heat (LE) fluxes from a large number of sites grouped in seven plant functional types (PFTs). It is an attempt to bridge the gap between the numerous site-specific parameter optimization works found in the literature and the generic parameterization used by most land surface models within each PFT. The present multi-site approach allows deriving PFT-generic sets of optimized parameters enhancing the agreement between measured and simulated fluxes at most of the sites considered, with performances often comparable to those of the corresponding site-specific optimizations. Besides reducing the PFT-averaged model-data root-mean-square difference (RMSD) and the associated daily output uncertainty, the optimization improves the simulated CO2 balance at tropical and temperate forests sites. The major site-level NEE adjustments at the seasonal scale are: reduced amplitude in C3 grasslands and boreal forests, increased seasonality in temperate evergreen forests, and better model-data phasing in temperate deciduous broadleaf forests. Conversely, the poorer performances in tropical evergreen broadleaf forests points to deficiencies regarding the modeling of phenology and soil water stress for this PFT. An evaluation with data-oriented estimates of photosynthesis (GPP) and ecosystem respiration (Reco) rates indicates distinctively improved simulations of both gross fluxes. The multi-site parameter sets are then tested against CO2 concentrations measured at 53 locations around the globe, showing significant adjustments of the modeled seasonality of atmospheric CO2 concentration, whose relevance seems PFT-dependent, along with an improved interannual variability. Lastly, a global scale evaluation with remote sensing NDVI measurements indicates an improvement of the simulated seasonal variations of

  10. Site selection and characterization processes for deep geologic disposal of high level nuclear waste

    SciTech Connect

    Costin, L.S.

    1997-10-01

    In this paper, the major elements of the site selection and characterization processes used in the US high level waste program are discussed. While much of the evolution of the site selection and characterization processes have been driven by the unique nature of the US program, these processes, which are well defined and documented, could be used as an initial basis for developing site screening, selection, and characterization programs in other countries. Thus, this paper focuses more on the process elements than the specific details of the US program.

  11. Ecotoxicity literature review of selected Hanford Site contaminants

    SciTech Connect

    Driver, C.J.

    1994-03-01

    Available information on the toxicity, food chain transport, and bioconcentration of several Hanford Site contaminants were reviewed. The contaminants included cesium-137, cobalt-60, europium, nitrate, plutonium, strontium-90, technetium, tritium, uranium, and chromium (III and VI). Toxicity and mobility in both aquatic and terrestrial systems were considered. For aquatic systems, considerable information was available on the chemical and/or radiological toxicity of most of the contaminants in invertebrate animals and fish. Little information was available on aquatic macrophyte response to the contaminants. Terrestrial animals such as waterfowl and amphibians that have high exposure potential in aquatic systems were also largely unrepresented in the toxicity literature. The preponderance of toxicity data for terrestrial biota was for laboratory mammals. Bioconcentration factors and transfer coefficients were obtained for primary producers and consumers in representative aquatic and terrestrial systems; however, little data were available for upper trophic level transfer, particularly for terrestrial predators. Food chain transport and toxicity information for the contaminants were generally lacking for desert or sage brush-steppe organisms, particularly plants and reptiles

  12. Discovery of 7-aminofuro[2,3-c]pyridine inhibitors of TAK1: optimization of kinase selectivity and pharmacokinetics.

    PubMed

    Hornberger, Keith R; Chen, Xin; Crew, Andrew P; Kleinberg, Andrew; Ma, Lifu; Mulvihill, Mark J; Wang, Jing; Wilde, Victoria L; Albertella, Mark; Bittner, Mark; Cooke, Andrew; Kadhim, Salam; Kahler, Jennifer; Maresca, Paul; May, Earl; Meyn, Peter; Romashko, Darlene; Tokar, Brianna; Turton, Roy

    2013-08-15

    The kinase selectivity and pharmacokinetic optimization of a series of 7-aminofuro[2,3-c]pyridine inhibitors of TAK1 is described. The intersection of insights from molecular modeling, computational prediction of metabolic sites, and in vitro metabolite identification studies resulted in a simple and unique solution to both of these problems. These efforts culminated in the discovery of compound 13a, a potent, relatively selective inhibitor of TAK1 with good pharmacokinetic properties in mice, which was active in an in vivo model of ovarian cancer.

  13. Coupling GIS and multivariate approaches to reference site selection for wadeable stream monitoring.

    PubMed

    Collier, Kevin J; Haigh, Andy; Kelly, Johlene

    2007-04-01

    Geographic Information System (GIS) was used to identify potential reference sites for wadeable stream monitoring, and multivariate analyses were applied to test whether invertebrate communities reflected a priori spatial and stream type classifications. We identified potential reference sites in segments with unmodified vegetation cover adjacent to the stream and in >85% of the upstream catchment. We then used various landcover, amenity and environmental impact databases to eliminate sites that had potential anthropogenic influences upstream and that fell into a range of access classes. Each site identified by this process was coded by four dominant stream classes and seven zones, and 119 candidate sites were randomly selected for follow-up assessment. This process yielded 16 sites conforming to reference site criteria using a conditional-probabilistic design, and these were augmented by an additional 14 existing or special interest reference sites. Non-metric multidimensional scaling (NMS) analysis of percent abundance invertebrate data indicated significant differences in community composition among some of the zones and stream classes identified a priori providing qualified support for this framework in reference site selection. NMS analysis of a range standardised condition and diversity metrics derived from the invertebrate data indicated a core set of 26 closely related sites, and four outliers that were considered atypical of reference site conditions and subsequently dropped from the network. Use of GIS linked to stream typology, available spatial databases and aerial photography greatly enhanced the objectivity and efficiency of reference site selection. The multi-metric ordination approach reduced variability among stream types and bias associated with non-random site selection, and provided an effective way to identify representative reference sites.

  14. Optimal number of sites in multi-site fisheries with fish stock dependent migrations.

    PubMed

    Moussaoui, Ali; Auger, Pierre; Lett, Christophe

    2011-07-01

    We present a stock-effort dynamical model of a fishery subdivided into fishing zones. The stock corresponds to a fish population moving between these zones, on which they are harvested by fishing fleets. We consider a linear chain of identical fishing zones. Fish movements between the zones, as well as vessels displacements, are assumed to take place at a faster time scale than the variation of the stock and the change of the fleet size. The vessels movements between the fishing areas are assumed to be stock dependent, i.e. the larger the stock density is in a zone the more vessels tends to remain in it. We take advantage of these two time scales to derive a reduced model governing the dynamics of the total harvested stock and the total fishing effort. Under some assumption, we obtain either a stable equilibrium or a stable limit cycle which involves large cyclic variations of the total fish stock and fishing effort. We show that there exists an optimal number of fishing zones that maximizes the total catch at equilibrium. We discuss the results in relation to fish aggregating devices (FADs) fisheries.

  15. The Why of Waiting: How mathematical Best-Choice Models demonstrate optimality of a Refractory Period in Habitat Selection

    NASA Astrophysics Data System (ADS)

    Brugger, M. F.; Waymire, E. C.; Betts, M. G.

    2010-12-01

    When brush mice, fruit flies, and other animals disperse from their natal site, they are immediately tasked with selecting new habitat, and must do so in such a way as to optimize their chances of surviving and breeding. Habitat selection connects the fields of behavioral ecology and landscape ecology by describing the role the physical quality of habitat plays in the selection process. Interestingly, observations indicate a strategy that occurs with a certain prescribed statistical regularity. It has been demonstrated (Stamps, Davis, Blozis, Boundy-Mills, Anim. Behav., 2007) that brush mice and fruit flies employ a refractory period: a period wherein a disperser, after leaving its natal site, will not accept highly-preferred natural habitats. Assuming this behavior has adaptive benefit, the apparent optimality of this strategy is mirrored in mathematical models of Stochastic Optimization. In one such model, the Classical Best Choice Problem, a selector views some permutation of the numbers {1, ..., n} one-by-one, seeing only their relative ranks and then either selecting that element or discarding it. The goal is to choose the ``n" element. The optimal strategy is to wait for the ⌈ n/e ⌉ th element and then pick an element if it is better than all those already seen; this might demonstrate why refractory periods have adaptive benefit. We present three extensions to the Best Choice Problem: a partial ordering on the set of elements (Kubicki & Morayne, SIAM J. Discrete Math., 2005), a new goal of minimizing the expected rank (Chow, Moriguti, Robbins, Samuels, Israel J. Math., 1964), and a general utility function (Gusein-Zade, Theory of Prob. and Applications, 1966), allowing the top r sites to be equally desirable. These extensions relate to ecological phenomena not represented by the Classical Problem. In each, we discuss the effect on the duration or existence of the Refractory Period.

  16. Resource Prospector: Mission Goals, Relevance and Site Selection

    NASA Technical Reports Server (NTRS)

    Colaprete, A.; Elphic, R. C.; Andrews, D.; Sanders, G.; McGovern, A.; Vaughan, R.; Heldmann, J.; Trimble, J.

    2015-01-01

    Over the last two decades a wealth of new observations of the moon have demonstrated a lunar water system dramatically more complex and rich than was deduced following the Apollo era. Observation from the Lunar Prospector Neutron Spectrometer (LPNS) revealed enhancements of hydrogen near the lunar poles. This observation has since been confirmed by the Lunar Reconnaissance Orbiter (LRO) Lunar Exploration Neutron Detector (LEND) instrument. The Lunar Crater Observation and Sensing Satellite (LCROSS) mission targeted a permanently shadowed, enhanced hydrogen location within the crater Cabeus. The LCROSS impact showed that at least some of the hydrogen enhancement is in the form of water ice and molecular hydrogen (H2). Other volatiles were also observed in the LCROSS impact cloud, including CO2, CO, an H2S. These volatiles, and in particular water, have the potential to be a valuable or enabling resource for future exploration. In large part due to these new findings, the NASA Human Exploration and Operations Mission Directorate (HEOMD) have selected a lunar volatiles prospecting mission for a concept study and potential flight in CY2020. The mission includes a rover-borne payload that (1) can locate surface and near-subsurface volatiles, (2) excavate and analyze samples of the volatile-bearing regolith (up to 1 meter), and (3) demonstrate the form, extractability and usefulness of the materials.

  17. Engineering development of selective agglomeration. Site closeout report

    SciTech Connect

    Not Available

    1993-04-01

    The Selective Agglomeration POC facility consisted of a coal crushing and grinding circuit, followed by an agglomeration circuit and product dewatering. (A plot plan of the facility is shown in Figure 1-2.) The coal crushing and grinding system consisted of a hammermill coal crusher, weigh-belt feeder, two ball mills (primary and secondary), and necessary hoppers, pumps, and conveyors. The mills were capable of providing coal over a range of grinds from a d{sub 50} of 125 to 25 microns. Slurry discharged from the ball mills was pumped to the agglomeration circuit. The agglomeration circuit began with a high-shear mixer, where diesel was added to the slurry to begin the formation of microagglomerates. The high-shear mixer was followed by two stages of conventional flotation cells for microagglomerate recovery. The second-stage-flotation-cell product was pumped to either a rotary-drum vacuum filter or a high-G centrifuge for dewatering. The dewatered product was then convoyed to the product pad from which dump trucks were used to transfer it to the utility plant located next to the facility. Plant tailings were pumped to the water clarifier for thickening and then dewatered in plate-and-frame filter presses. These dewatered tailings were also removed to the utility via dump truck. Clarified water (thickener overflow) was recycled to the process via a head tank.

  18. Guidance for Optimizing Remedy Evaluation, Selection, and Design

    DTIC Science & Technology

    2004-04-01

    soils that are similarly contaminated, then on-site treatment (e.g., a biopile ) followed by on-site disposal (as clean fill or daily cover at the base... membrane interface probe followed by confirmation sampling with a Geoprobe™ could be used to better define contaminant extent prior to implementation of...presence of a nearby source. Vari- ous characterization technologies can then be applied to further delineate the source. For exam- ple, a membrane

  19. Tuning the ion selectivity of tetrameric cation channels by changing the number of ion binding sites

    SciTech Connect

    Derebe, Mehabaw G.; Sauer, David B.; Zeng, Weizhong; Alam, Amer; Shi, Ning; Jiang, Youxing

    2015-11-30

    Selective ion conduction across ion channel pores is central to cellular physiology. To understand the underlying principles of ion selectivity in tetrameric cation channels, we engineered a set of cation channel pores based on the nonselective NaK channel and determined their structures to high resolution. These structures showcase an ensemble of selectivity filters with a various number of contiguous ion binding sites ranging from 2 to 4, with each individual site maintaining a geometry and ligand environment virtually identical to that of equivalent sites in K{sup +} channel selectivity filters. Combined with single channel electrophysiology, we show that only the channel with four ion binding sites is K{sup +} selective, whereas those with two or three are nonselective and permeate Na{sup +} and K{sup +} equally well. These observations strongly suggest that the number of contiguous ion binding sites in a single file is the key determinant of the channel's selectivity properties and the presence of four sites in K{sup +} channels is essential for highly selective and efficient permeation of K{sup +} ions.

  20. Optimal Bandwidth Selection in Observed-Score Kernel Equating

    ERIC Educational Resources Information Center

    Häggström, Jenny; Wiberg, Marie

    2014-01-01

    The selection of bandwidth in kernel equating is important because it has a direct impact on the equated test scores. The aim of this article is to examine the use of double smoothing when selecting bandwidths in kernel equating and to compare double smoothing with the commonly used penalty method. This comparison was made using both an equivalent…

  1. Enzymatic site-selectivity enabled by structure-guided directed evolution.

    PubMed

    Wang, Jian-Bo; Li, Guangyue; Reetz, Manfred T

    2017-03-15

    Biocatalytic site-selective (regioselective) organic transformations have been practiced for decades, but the traditional limitations of enzymes regarding narrow substrate acceptance and the often observed insufficient degree of selectivity have persisted until recently. With the advent of directed evolution, it is possible to engineer site-selectivity to suit the needs of organic chemists. This review features recent progress in this exciting research area, selected examples involving P450 monooxygenases, halogenases and Baeyer-Villiger monooxygenases being featured for illustrative purposes. The complementary nature of enzymes and man-made catalysts is emphasized.

  2. Selectivity of ORC binding sites and the relation to replication timing, fragile sites, and deletions in cancers

    PubMed Central

    Miotto, Benoit; Ji, Zhe; Struhl, Kevin

    2016-01-01

    The origin recognition complex (ORC) binds sites from which DNA replication is initiated. We address ORC binding selectivity in vivo by mapping ∼52,000 ORC2 binding sites throughout the human genome. The ORC binding profile is broader than those of sequence-specific transcription factors, suggesting that ORC is not bound or recruited to specific DNA sequences. Instead, ORC binds nonspecifically to open (DNase I-hypersensitive) regions containing active chromatin marks such as H3 acetylation and H3K4 methylation. ORC sites in early and late replicating regions have similar properties, but there are far more ORC sites in early replicating regions. This suggests that replication timing is due primarily to ORC density and stochastic firing of origins. Computational simulation of stochastic firing from identified ORC sites is in accord with replication timing data. Large genomic regions with a paucity of ORC sites are strongly associated with common fragile sites and recurrent deletions in cancers. We suggest that replication origins, replication timing, and replication-dependent chromosome breaks are determined primarily by the genomic distribution of activator proteins at enhancers and promoters. These activators recruit nucleosome-modifying complexes to create the appropriate chromatin structure that allows ORC binding and subsequent origin firing. PMID:27436900

  3. Oviposition site selection by the grasshoppers Melanoplus borealis and M. sanguinipes (Orthoptera: Acrididae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Female grasshoppers can affect the fitness of their offspring through their selection of oviposition sites. Successful embryological development depends on suitable temperature and moisture levels, factors which may vary considerably on a fine scale in natural environments where grasshoppers occur. ...

  4. Optimization of the High-Frequency Radar Sites in the Bering Strait Region

    DTIC Science & Technology

    2015-02-01

    Optimization of the High-Frequency Radar Sites in the Bering Strait Region GLEB PANTELEEV International Arctic Research Center, University of Alaska ...Fairbanks, Fairbanks, Alaska , and National Research Tomsk Polytechnic University, Tomsk, Russia MAX YAREMCHUK Naval Research Laboratory, Stennis Space...Center, Mississippi JACOB STROH University of Alaska Fairbanks, Fairbanks, Alaska PAMELA POSEY AND DAVID HEBERT Naval Research Laboratory, Stennis

  5. Stochastic injection-strategy optimization for the preliminary assessment of candidate geological storage sites

    NASA Astrophysics Data System (ADS)

    Cody, Brent M.; Baù, Domenico; González-Nicolás, Ana

    2015-09-01

    Geological carbon sequestration (GCS) has been identified as having the potential to reduce increasing atmospheric concentrations of carbon dioxide (CO2). However, a global impact will only be achieved if GCS is cost-effectively and safely implemented on a massive scale. This work presents a computationally efficient methodology for identifying optimal injection strategies at candidate GCS sites having uncertainty associated with caprock permeability, effective compressibility, and aquifer permeability. A multi-objective evolutionary optimization algorithm is used to heuristically determine non-dominated solutions between the following two competing objectives: (1) maximize mass of CO2 sequestered and (2) minimize project cost. A semi-analytical algorithm is used to estimate CO2 leakage mass rather than a numerical model, enabling the study of GCS sites having vastly different domain characteristics. The stochastic optimization framework presented herein is applied to a feasibility study of GCS in a brine aquifer in the Michigan Basin (MB), USA. Eight optimization test cases are performed to investigate the impact of decision-maker (DM) preferences on Pareto-optimal objective-function values and carbon-injection strategies. This analysis shows that the feasibility of GCS at the MB test site is highly dependent upon the DM's risk-adversity preference and degree of uncertainty associated with caprock integrity. Finally, large gains in computational efficiency achieved using parallel processing and archiving are discussed.

  6. An opiate binding site in the rat brain is highly selective for 4,5-epoxymorphinans.

    PubMed

    Grevel, J; Sadée, W

    1983-09-16

    In vitro binding studies have demonstrated the existence of multiple opiate receptor types. An additional site in the rat brain (termed the lambda site) is distinct from the established types by its selectivity for 4,5-epoxymorphinans (such as naloxone and morphine). While the lambda site displays a high affinity for naloxone in vivo and in vitro in fresh brain membrane homogenates, these sites rapidly convert in vitro to a state of low affinity. The regional distribution of the lambda site in the brain is strikingly different from that of the classic opiate receptor types.

  7. Self-Selection, Optimal Income Taxation, and Redistribution

    ERIC Educational Resources Information Center

    Amegashie, J. Atsu

    2009-01-01

    The author makes a pedagogical contribution to optimal income taxation. Using a very simple model adapted from George A. Akerlof (1978), he demonstrates a key result in the approach to public economics and welfare economics pioneered by Nobel laureate James Mirrlees. He shows how incomplete information, in addition to the need to preserve…

  8. A Regression Design Approach to Optimal and Robust Spacing Selection.

    DTIC Science & Technology

    1981-07-01

    release and sale; its distribution is unlimited Acceso For NTIS GRA&I DEPARTMENT OF STATISTICS DTIC TAB Unannounced Southern Methodist University F...such as the Cauchy where A is a constant multiple of the identity. In fact, for the Cauchy distribution asymptotically optimal spacing sequences for

  9. Optimal design and selection of magneto-rheological brake types based on braking torque and mass

    NASA Astrophysics Data System (ADS)

    Nguyen, Q. H.; Lang, V. T.; Choi, S. B.

    2015-06-01

    In developing magnetorheological brakes (MRBs), it is well known that the braking torque and the mass of the MRBs are important factors that should be considered in the product’s design. This research focuses on the optimal design of different types of MRBs, from which we identify an optimal selection of MRB types, considering braking torque and mass. In the optimization, common types of MRBs such as disc-type, drum-type, hybrid-type, and T-shape types are considered. The optimization problem is to find an optimal MRB structure that can produce the required braking torque while minimizing its mass. After a brief description of the configuration of the MRBs, the MRBs’ braking torque is derived based on the Herschel-Bulkley rheological model of the magnetorheological fluid. Then, the optimal designs of the MRBs are analyzed. The optimization objective is to minimize the mass of the brake while the braking torque is constrained to be greater than a required value. In addition, the power consumption of the MRBs is also considered as a reference parameter in the optimization. A finite element analysis integrated with an optimization tool is used to obtain optimal solutions for the MRBs. Optimal solutions of MRBs with different required braking torque values are obtained based on the proposed optimization procedure. From the results, we discuss the optimal selection of MRB types, considering braking torque and mass.

  10. Colony site selection and abandonment by least terns Sterna antillarum in New Jersey, USA

    USGS Publications Warehouse

    Kotliar, Natasha B.; Burger, Joanna

    1986-01-01

    The presence of shells or pebbles in a sandy substrate, and short, sparse vegetation, were the habitat characteristics of New Jersey least tern colony sites most strongly correlated with colony site selection. Dredge spoil sites had significantly greater evidence of human disturbance, distance to water, and proportion of coarse particles in the substrate than beach sites. These differences may have contributed to the smaller colonines and greater colony turnover rates at spoil sites relative to beach sites. Overall, abandoned colony site characteristics did not differ significantly from occupied sites. However, human disturbance, over-growth of vegetation, predation, and flooding were all prevalent at colonies prior to abandonment. The results of this study suggest techniques for habitat management of both least and little terns.

  11. Development of oxidative coupling strategies for site-selective protein modification.

    PubMed

    ElSohly, Adel M; Francis, Matthew B

    2015-07-21

    the challenges and opportunities associated with the optimization of site-selective chemistries that target native amino acids. We close by discussing the most recent reports from our laboratory that have capitalized on the unique reactivity of o-iminoquinone derivatives. We discuss the various oxidants and conditions that can be used to generate these reactive intermediates from appropriate precursors, as well as the product distributions that result. We also describe our work to determine the nature of iminoquinone reactivity with proteins and peptides bearing free N-terminal amino groups. Through this discussion, we hope to facilitate the use of oxidative approaches to protein bioconjugation, as well as inspire the discovery of new reactions for the site-selective modification of biomolecular targets.

  12. Data-Driven Surface Traversability Analysis for Mars 2020 Landing Site Selection

    NASA Technical Reports Server (NTRS)

    Ono, Masahiro; Rothrock, Brandon; Almeida, Eduardo; Ansar, Adnan; Otero, Richard; Huertas, Andres; Heverly, Matthew

    2015-01-01

    The objective of this paper is three-fold: 1) to describe the engineering challenges in the surface mobility of the Mars 2020 Rover mission that are considered in the landing site selection processs, 2) to introduce new automated traversability analysis capabilities, and 3) to present the preliminary analysis results for top candidate landing sites. The analysis capabilities presented in this paper include automated terrain classification, automated rock detection, digital elevation model (DEM) generation, and multi-ROI (region of interest) route planning. These analysis capabilities enable to fully utilize the vast volume of high-resolution orbiter imagery, quantitatively evaluate surface mobility requirements for each candidate site, and reject subjectivity in the comparison between sites in terms of engineering considerations. The analysis results supported the discussion in the Second Landing Site Workshop held in August 2015, which resulted in selecting eight candidate sites that will be considered in the third workshop.

  13. Leaving safety to visit a feeding site: is it optimal to hesitate while exposed?

    PubMed Central

    2017-01-01

    Animals living in complex environments experience differing risks of predation depending upon their location within the landscape. An animal could reduce the risk it experiences by remaining in a refuge site, but it may need to emerge from its refuge and enter more dangerous sites for feeding and other activities. Here, I consider the actions of an animal choosing to travel a short distance between a safe refuge and a dangerous foraging site, such as a bird leaving cover to visit a feeder. Although much work has been conducted examining the choice between a refuge and a foraging site when faced with a trade-off between starvation and predation risk, the work presented here is the first to consider the travel behaviour between these locations. Using state-dependent stochastic dynamic programming, I illustrate that there are several forms of optimal behaviour that can emerge. In some situations, the animal should choose to travel without stopping between sites, but in other cases, it is optimal for the animal to travel hesitantly towards the food, and to stop its travel at a point before it reaches the refuge. I discuss how this hesitant ‘dawdling’ behaviour may be optimal, and suggest further work to test these predictions. PMID:28280590

  14. Leaving safety to visit a feeding site: is it optimal to hesitate while exposed?

    PubMed

    Rands, Sean A

    2017-01-01

    Animals living in complex environments experience differing risks of predation depending upon their location within the landscape. An animal could reduce the risk it experiences by remaining in a refuge site, but it may need to emerge from its refuge and enter more dangerous sites for feeding and other activities. Here, I consider the actions of an animal choosing to travel a short distance between a safe refuge and a dangerous foraging site, such as a bird leaving cover to visit a feeder. Although much work has been conducted examining the choice between a refuge and a foraging site when faced with a trade-off between starvation and predation risk, the work presented here is the first to consider the travel behaviour between these locations. Using state-dependent stochastic dynamic programming, I illustrate that there are several forms of optimal behaviour that can emerge. In some situations, the animal should choose to travel without stopping between sites, but in other cases, it is optimal for the animal to travel hesitantly towards the food, and to stop its travel at a point before it reaches the refuge. I discuss how this hesitant 'dawdling' behaviour may be optimal, and suggest further work to test these predictions.

  15. A smartphone-optimized web site for conveniently viewing otolaryngology journal abstracts.

    PubMed

    Golub, Justin S; Sharma, Arun; Samy, Ravi N

    2014-12-01

    Access to the medical literature has not kept pace with the mobile revolution. We aimed to (1) gauge interest in a smartphone-optimized Web site for conveniently accessing otolaryngology literature and (2) create an easy-to-access and convenient Web site that displays otolaryngology journal abstracts in a format optimized for smartphones. A survey was sent to physicians of a major US academic otolaryngology-head and neck surgery department. Demographics, literature-browsing habits, and barriers to staying updated were assessed. The response rate was 87%. Ninety-one percent of respondents used a smartphone, and 85% wished they could stay more up to date with the otolaryngology literature. Most respondents believed a convenient smartphone-optimized Web site could help them achieve this goal. A Web site was then developed in collaboration with a university creative department as a proof of concept. The site uses a simple RSS aggregator to display journal abstracts formatted for smartphone-sized screens (www.otosurg.com).

  16. Optimizing drilling performance using a selected drilling fluid

    DOEpatents

    Judzis, Arnis [Salt Lake City, UT; Black, Alan D [Coral Springs, FL; Green, Sidney J [Salt Lake City, UT; Robertson, Homer A [West Jordan, UT; Bland, Ronald G [Houston, TX; Curry, David Alexander [The Woodlands, TX; Ledgerwood, III, Leroy W.

    2011-04-19

    To improve drilling performance, a drilling fluid is selected based on one or more criteria and to have at least one target characteristic. Drilling equipment is used to drill a wellbore, and the selected drilling fluid is provided into the wellbore during drilling with the drilling equipment. The at least one target characteristic of the drilling fluid includes an ability of the drilling fluid to penetrate into formation cuttings during drilling to weaken the formation cuttings.

  17. Selection of den sites by black bears in the southern Appalachians

    USGS Publications Warehouse

    Reynolds-Hogland, M. J.; Mitchell, M.S.; Powell, R.A.; Brown, D.C.

    2007-01-01

    We evaluated selection of den sites by American black bears (Ursus americanus) in the Pisgah Bear Sanctuary, western North Carolina, by comparing characteristics of dens at 53 den sites with availability of habitat characteristics in annual home ranges of bears and in the study area. We also tested whether den-site selection differed by sex, age, and reproductive status of bears. In addition, we evaluated whether the den component of an existing habitat model for black bears predicted where bears would select den sites. We found bears selected den sites far from gravel roads, on steep slopes, and at high elevations relative to what was available in both annual home ranges and in the study area. Den-site selection did not differ by sex or age, but it differed by reproductive status. Adult females with cubs preferred to den in areas that were relatively far from gravel roads, but adult females without cubs did not. The habitat model overestimated the value of areas near gravel roads, underestimated the value of moderately steep areas, and did not include elevation as a predictor variable. Our results highlight the importance of evaluating den selection in terms of both use and availability of den characteristics. ?? 2007 American Society of Mammalogists.

  18. 10 CFR 960.3-2-2-2 - Selection of sites within geohydrologic settings.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Selection of sites within geohydrologic settings. 960.3-2-2-2 Section 960.3-2-2-2 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-2-2-2...

  19. 10 CFR 960.3-2-2-2 - Selection of sites within geohydrologic settings.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Selection of sites within geohydrologic settings. 960.3-2-2-2 Section 960.3-2-2-2 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-2-2-2...

  20. 10 CFR 960.3-2-2-2 - Selection of sites within geohydrologic settings.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Selection of sites within geohydrologic settings. 960.3-2-2-2 Section 960.3-2-2-2 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-2-2-2...

  1. 10 CFR 960.3-2-2-2 - Selection of sites within geohydrologic settings.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Selection of sites within geohydrologic settings. 960.3-2-2-2 Section 960.3-2-2-2 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-2-2-2...

  2. 10 CFR 960.3-2-2-2 - Selection of sites within geohydrologic settings.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Selection of sites within geohydrologic settings. 960.3-2-2-2 Section 960.3-2-2-2 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-2-2-2...

  3. Site Selection and Automatically Calculated Rover Traverse for a Lunar Teleoperated Landing Mission

    NASA Astrophysics Data System (ADS)

    Kamps, Oscar; Foing, Bernard; Flahaut, Jessica

    2016-04-01

    With the recent interest for the Moon, and the plans from the ESA side to do a tele-operated mission from Earth or lunar orbit, it is important to target a well-defined location. One of the major topics to study on the Moon is the existence and availability of volatiles and ices. Because no lander ever visited one of the poles on the Moon the theories with respect to water ice are only based on data from orbiters. In a four month research project the data from the orbiters was used for assessing potential landing sites and a rover traverse planning. Mainly data from the Prospector and LRO were used to select regions of interest. The prior selection was based on slope, temperature and a geological map from the USGS. Three sites on both the North as South Pole were used to test a proposed method for rover traverse planning. Besides the scientific interest, the sites where assessed on its accessibility for landing and roving. This assessment was done based on some assumptions what would be possible for landing and roving. For landing sites it was proposed to pick a site larger than 1km in diameter, in a (partial) illuminated area with a slope lower than 5o, which was inside an area which would be accessible for a rover. The requirements to be selected as accessible area was a slope lower than 20o, the largest polygon which meets this requirement was chosen as accessible area. As destination a site in the PSR was selected which was inside the accessible area and had extremely low temperatures. The boundary for extremely low was defined as 54K which is the sublimation temperature of CO2 in lunar atmospheric pressure. As additional target for the rover a site was selected where the temperature difference would be more than 150K to study volatile migration processes. A combination of tools in ArcGIS were used to do the site selection and rover traverse planning. In the end Rozhdestvensky and Amundsen were selected as most accessible and interesting. After comparing both

  4. Targeting hunter distribution based on host resource selection and kill sites to manage disease risk

    PubMed Central

    Dugal, Cherie J; van Beest, Floris M; Vander Wal, Eric; Brook, Ryan K

    2013-01-01

    Endemic and emerging diseases are rarely uniform in their spatial distribution or prevalence among cohorts of wildlife. Spatial models that quantify risk-driven differences in resource selection and hunter mortality of animals at fine spatial scales can assist disease management by identifying high-risk areas and individuals. We used resource selection functions (RSFs) and selection ratios (SRs) to quantify sex- and age-specific resource selection patterns of collared (n = 67) and hunter-killed (n = 796) nonmigratory elk (Cervus canadensis manitobensis) during the hunting season between 2002 and 2012, in southwestern Manitoba, Canada. Distance to protected area was the most important covariate influencing resource selection and hunter-kill sites of elk (AICw = 1.00). Collared adult males (which are most likely to be infected with bovine tuberculosis (Mycobacterium bovis) and chronic wasting disease) rarely selected for sites outside of parks during the hunting season in contrast to adult females and juvenile males. The RSFs showed selection by adult females and juvenile males to be negatively associated with landscape-level forest cover, high road density, and water cover, whereas hunter-kill sites of these cohorts were positively associated with landscape-level forest cover and increasing distance to streams and negatively associated with high road density. Local-level forest was positively associated with collared animal locations and hunter-kill sites; however, selection was stronger for collared juvenile males and hunter-killed adult females. In instances where disease infects a metapopulation and eradication is infeasible, a principle goal of management is to limit the spread of disease among infected animals. We map high-risk areas that are regularly used by potentially infectious hosts but currently underrepresented in the distribution of kill sites. We present a novel application of widely available data to target hunter distribution based on host resource

  5. Targeting hunter distribution based on host resource selection and kill sites to manage disease risk.

    PubMed

    Dugal, Cherie J; van Beest, Floris M; Vander Wal, Eric; Brook, Ryan K

    2013-10-01

    Endemic and emerging diseases are rarely uniform in their spatial distribution or prevalence among cohorts of wildlife. Spatial models that quantify risk-driven differences in resource selection and hunter mortality of animals at fine spatial scales can assist disease management by identifying high-risk areas and individuals. We used resource selection functions (RSFs) and selection ratios (SRs) to quantify sex- and age-specific resource selection patterns of collared (n = 67) and hunter-killed (n = 796) nonmigratory elk (Cervus canadensis manitobensis) during the hunting season between 2002 and 2012, in southwestern Manitoba, Canada. Distance to protected area was the most important covariate influencing resource selection and hunter-kill sites of elk (AICw = 1.00). Collared adult males (which are most likely to be infected with bovine tuberculosis (Mycobacterium bovis) and chronic wasting disease) rarely selected for sites outside of parks during the hunting season in contrast to adult females and juvenile males. The RSFs showed selection by adult females and juvenile males to be negatively associated with landscape-level forest cover, high road density, and water cover, whereas hunter-kill sites of these cohorts were positively associated with landscape-level forest cover and increasing distance to streams and negatively associated with high road density. Local-level forest was positively associated with collared animal locations and hunter-kill sites; however, selection was stronger for collared juvenile males and hunter-killed adult females. In instances where disease infects a metapopulation and eradication is infeasible, a principle goal of management is to limit the spread of disease among infected animals. We map high-risk areas that are regularly used by potentially infectious hosts but currently underrepresented in the distribution of kill sites. We present a novel application of widely available data to target hunter distribution based on host resource

  6. Criteria for Site Selection of Temporary Shelters after Earthquakes: a Delphi Panel

    PubMed Central

    Soltani, Ahmad; Ardalan, Ali; Darvishi Boloorani, Ali; Haghdoost, AliAkbar; Hosseinzadeh-Attar, Mohammad Javad

    2015-01-01

    Introduction: After a devastating earthquake, the site selection for the sheltering of earthquake victims is an important task. In order to generate a list of appropriate criteria for deciding on temporary sheltering site selection, we systematically combined the experience of experts and the findings of published documents in this study. Methods: Having explored published papers, we generated a list of criteria for the selection of the best location for temporary sheltering. In the next step, all criteria were presented to a group of experts in Iran and after a scientific discussion, the list was updated. In the last step, the final list of criteria was developed using the Delphi method in three rounds. Results: Based on our previous systematic review, 27 criteria were presented for sheltering site selection. Expert interviews added 12 more items to them. The Delphi process approved 21 criteria of all proposed ones. These items then grouped into four categories: land suitability, socio-cultural considerations, service availability and disaster risk reduction. Discussion: After an earthquake, our list of criteria may help the disaster team to select the best locations for temporary sheltering with minimum confusion. The consent of the earthquake victims and cost reduction of the operation would be the minimum benefits of using the appropriate criteria. These criteria also could be used by researchers to make objective and reproducible assessments of temporary sheltering site selection. Key words: Criteria, Earthquake, Model, Site selection, Temporary shelter, PMID:26693079

  7. Cyberinfrastructure for eddy covariance systems: From site selection to data submission

    NASA Astrophysics Data System (ADS)

    Jaimes, A.; Salayandia, L.; Laney, C.; Tweedie, C. E.

    2011-12-01

    Eddy covariance (EC) is one of the most direct methods to measure the vertical turbulence that drives the mass exchange of heat, water vapor, and carbon within the atmospheric boundary layer. EC is mathematically complex and challenging to implement, especially for a researcher with little experience. Therefore, significant care in setting up the EC equipment and processing data is required; failure to do so may cause numerous types of data errors. In addition, analysis of data from flux towers is site specific, and it is nearly impossible to use a uniform methodology across different ecosystems. Although, a large effort to unify different approaches is being done by national and international flux networks (e.g., FLUXNET, Ameriflux, CarboEurope, NEON), as well as the flux community in general; Implementation remains challenging especially for non-experience users and small labs striving to collaborate with large networks. Here, we introduce Semantic Abstract Workflows (SAWs) as a novel approach to document and manage the processes used for the implementation of an eddy covariance research site. From site selection, data collection, data processing, data preparation for submission to community networks. Our eddy covariance tower represents the Chihuahuan Desert and specifically aids the study of land-atmosphere interactions in a mixed creosote (Larrea tridentata) - mesquite (Prosopis glandulosa) shrubland located within the Jornada Experimental Range, USDA ARS, Las Cruces, NM. . Documented processes in the form of SAWs were constructed using the Wdo-it tool1. These SAWs are currently being used to annotate data as is being generated from the Jornada EC site. The Provenance Mark-up Language (PML) is being used to structure such annotations in a form that effectively captures provenance of data. Another tool called Probe-IT is then used to analyze data from a provenance perspective. SAWs provide a simple graphical notation intended to facilitate reuse of process

  8. Resource Utilization and Site Selection for a Self-Sufficient Martian Outpost

    NASA Technical Reports Server (NTRS)

    Barker, Donald; Chamitoff, Gregory; James, George

    1998-01-01

    As a planet with striking similarities to Earth, Mars is an important focus for scientific research aimed at understanding the processes of planetary evolution and the formation of our solar system. Fortunately, Mars is also a planet with abundant natural resources, including assessible materials that can be used to support human life and to sustain a self-sufficient martian outpost. Resources required include water, breathable air, food, shelter, energy, and fuel. Through a mission design based on in situ resource development, we can establish a permanent outpost on Mars beginning with the first manned mission. This paper examines the potential for supporting the first manned mission with the objective of achieving self-sufficiency through well-understood resource development and a program of rigorous scientific research aimed at extending that capability. We examine the potential for initially extracting critical resources from the martian environment, and discuss the scientific investigations required to identify additional resources in the atmosphere, on the surface, and within the subsurface. We also discuss our current state of knowledge of Mars, technical considerations of resource utilization, and using unmanned missions' data for selecting an optimal site. The primary goal of achieving self-sufficiency on Mars would accelerate the development of human colonization beyond Earth, while providing a robust and permanent martian base from which humans can explore and conduct long-term research on planetary evolution, the solar system, and life itself.

  9. a New Framework for Geospatial Site Selection Using Artificial Neural Networks as Decision Rules: a Case Study on Landfill Sites

    NASA Astrophysics Data System (ADS)

    Abujayyab, S. K. M.; Ahamad, M. A. S.; Yahya, A. S.; Saad, A.-M. H. Y.

    2015-10-01

    This paper briefly introduced the theory and framework of geospatial site selection (GSS) and discussed the application and framework of artificial neural networks (ANNs). The related literature on the use of ANNs as decision rules in GSS is scarce from 2000 till 2015. As this study found, ANNs are not only adaptable to dynamic changes but also capable of improving the objectivity of acquisition in GSS, reducing time consumption, and providing high validation. ANNs make for a powerful tool for solving geospatial decision-making problems by enabling geospatial decision makers to implement their constraints and imprecise concepts. This tool offers a way to represent and handle uncertainty. Specifically, ANNs are decision rules implemented to enhance conventional GSS frameworks. The main assumption in implementing ANNs in GSS is that the current characteristics of existing sites are indicative of the degree of suitability of new locations with similar characteristics. GSS requires several input criteria that embody specific requirements and the desired site characteristics, which could contribute to geospatial sites. In this study, the proposed framework consists of four stages for implementing ANNs in GSS. A multilayer feed-forward network with a backpropagation algorithm was used to train the networks from prior sites to assess, generalize, and evaluate the outputs on the basis of the inputs for the new sites. Two metrics, namely, confusion matrix and receiver operating characteristic tests, were utilized to achieve high accuracy and validation. Results proved that ANNs provide reasonable and efficient results as an accurate and inexpensive quantitative technique for GSS.

  10. Selection of magnetorheological brake types via optimal design considering maximum torque and constrained volume

    NASA Astrophysics Data System (ADS)

    Nguyen, Q. H.; Choi, S. B.

    2012-01-01

    This research focuses on optimal design of different types of magnetorheological brakes (MRBs), from which an optimal selection of MRB types is identified. In the optimization, common types of MRB such as disc-type, drum-type, hybrid-types, and T-shaped type are considered. The optimization problem is to find the optimal value of significant geometric dimensions of the MRB that can produce a maximum braking torque. The MRB is constrained in a cylindrical volume of a specific radius and length. After a brief description of the configuration of MRB types, the braking torques of the MRBs are derived based on the Herschel-Bulkley model of the MR fluid. The optimal design of MRBs constrained in a specific cylindrical volume is then analysed. The objective of the optimization is to maximize the braking torque while the torque ratio (the ratio of maximum braking torque and the zero-field friction torque) is constrained to be greater than a certain value. A finite element analysis integrated with an optimization tool is employed to obtain optimal solutions of the MRBs. Optimal solutions of MRBs constrained in different volumes are obtained based on the proposed optimization procedure. From the results, discussions on the optimal selection of MRB types depending on constrained volumes are given.

  11. Positive Darwinian selection at single amino acid sites conferring plant virus resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Explicit evaluation of the accuracy and power of Maximum Likelihood and Bayesian methods for detecting site-specific positive Darwinian selection presents a challenge because selective consequences of single amino acid changes are generally unknown. We exploit extensive molecular and functional cha...

  12. Optimizing the yield and selectivity of high purity nanoparticle clusters

    NASA Astrophysics Data System (ADS)

    Pease, Leonard F.

    2011-05-01

    Here we investigate the parameters that govern the yield and selectivity of small clusters composed of nanoparticles using a Monte Carlo simulation that accounts for spatial and dimensional distributions in droplet and nanoparticle density and size. Clustering nanoparticles presents a powerful paradigm with which to access properties not otherwise available using individual molecules, individual nanoparticles or bulk materials. However, the governing parameters that precisely tune the yield and selectivity of clusters fabricated via an electrospray droplet evaporation method followed by purification with differential mobility analysis (DMA) remain poorly understood. We find that the product of the electrospray droplet mean diameter to the third power and nanoparticle concentration governs the yield of individual clusters, while the ratio of the nanoparticle standard deviation to the mean diameter governs the selectivity. The resulting, easily accessible correlations may be used to minimize undesirable clustering, such as protein aggregation in the biopharmaceutical industry, and maximize the yield of a particular type of cluster for nanotechnology and energy applications.

  13. Stratigraphic Profiles for Selected Hanford Site Seismometer Stations and Other Locations

    SciTech Connect

    Last, George V.

    2014-02-01

    Stratigraphic profiles were constructed for eight selected Hanford Site seismometer stations, five Hanford Site facility reference locations, and seven regional three-component broadband seismometer stations. These profiles provide interpretations of the subsurface layers to support estimation of ground motions from past earthquakes, and the prediction of ground motions from future earthquakes. In most cases these profiles terminated at the top of the Wanapum Basalt, but at selected sites profiles were extended down to the top of the crystalline basement. The composite one-dimensional stratigraphic profiles were based primarily on previous interpretations from nearby boreholes, and in many cases the nearest deep borehole is located kilometers away.

  14. Golden-cheeked warbler males participate in nest-site selection

    USGS Publications Warehouse

    Graber, A.E.; Davis, C.A.; Leslie, David M.

    2006-01-01

    Nest-site selection behaviors have rarely been described for songbirds. Furthermore, male involvement in nest-site selection is generally assumed to be minimal among most species, especially those predominantly exhibiting female nest building. This assumption has held true for the federally endangered Golden-cheeked Warbler (Dendroica chrysoparia), a breeding resident of central Texas. We observed Golden-cheeked Warbler males and females searching for nest sites together on three separate occasions, 2001-2003. Although rare, such observations add to our knowledge of the life history of songbirds.

  15. Dynamic Albedo of Neutrons Instrument Onboard MSL Mission: Selection of Landing Site from HEND/Odyssey Data

    NASA Astrophysics Data System (ADS)

    Litvak, M. L.; Kozyrev, A. S.; Malakhov, A. V.; Mitrofanov, I. G.; Mokrousov, M. I.; Sanin, A. B.; Tretyakov, V. I.; Vostrukhin, A.

    2007-03-01

    This abstract contains description of DAN instrument selected for MSL mission and results of analysis of prioritized landing site selections (First MSL Landing Site Workshop) based on HEND/Odyssey data.

  16. Crystal-Site-Selective Spectrum of Fe3O4 Obtained by Mössbauer Diffraction

    NASA Astrophysics Data System (ADS)

    Nakamura, Shin; Mitsui, Takaya; Fujiwara, Kosuke; Ikeda, Naoshi; Kurokuzu, Masayuki; Shimomura, Susumu

    2017-02-01

    We have succeeded for the first time in obtaining a crystal-site-selective Mössbauer spectrum of Fe3O4 using the Mössbauer diffractometer at SPring-8 BL11XU. In order to extract the nuclear resonant scattering, which provides the crystal-site-selective emission spectrum, reflections having a Bragg angle near 45° were used. The 666 and 10 10 0 reflection spectra reveal only B- and A-site spectra, respectively. Mössbauer diffraction spectroscopy enables us to measure the crystal-site-selective spectrum and to determine the precise hyperfine structure. This technique provides new possibilities for studying the local crystallographic and magnetic structure on iron sublattices in various multisite materials.

  17. Selection of optimal sensors for predicting performance of polymer electrolyte membrane fuel cell

    NASA Astrophysics Data System (ADS)

    Mao, Lei; Jackson, Lisa

    2016-10-01

    In this paper, sensor selection algorithms are investigated based on a sensitivity analysis, and the capability of optimal sensors in predicting PEM fuel cell performance is also studied using test data. The fuel cell model is developed for generating the sensitivity matrix relating sensor measurements and fuel cell health parameters. From the sensitivity matrix, two sensor selection approaches, including the largest gap method, and exhaustive brute force searching technique, are applied to find the optimal sensors providing reliable predictions. Based on the results, a sensor selection approach considering both sensor sensitivity and noise resistance is proposed to find the optimal sensor set with minimum size. Furthermore, the performance of the optimal sensor set is studied to predict fuel cell performance using test data from a PEM fuel cell system. Results demonstrate that with optimal sensors, the performance of PEM fuel cell can be predicted with good quality.

  18. Structure based lead optimization approach in discovery of selective DPP4 inhibitors.

    PubMed

    Ghate, Manjunath; Jain, Shailesh V

    2013-05-01

    Diabetes mellitus is a chronic progressive metabolic disorder that has profound consequences for individuals, families, and society. To date, main available oral antidiabetic medications target either insulin resistance (metformin, glitazones), or insulin deficiency (sulfonylureas, glinides), but leading to shortfalls in medication. Advancement in modern oral hypoglycemic agents may be encouraged with or in place of traditional therapies. The lower risk for hypoglycemic events as compared with other insulinotropic or insulin-sensitizing agents make DPP-4 inhibitors very promising candidates for a more physiological treatment of type-2 diabetes. Only some DPP-4 inhibitors are currently used for the treatment of type 2 diabetes (T2DM) and various inhibitors currently undergoing animal and human testing. A number of catalytically active DPPs distinct from DPP-4 (DPP II, FAP, DPP-8, and DPP-9) have been described that is associated with side-effect and toxicity. To discover potent and selective and safer drugs in a shorter time frame and with reduced cost it requires using an innovative approach for designing novel inhibitors. This review article focuses on the status of advanced lead candidates of DPP group and their binding affinity with the active site residue of target structure which help in discovery of potent and selective DPP-4 inhibitors by lead optimization approach.

  19. Reference site selection for wetland condition assessments: Integrating best professional judgement and objective selection criteria

    EPA Science Inventory

    The National Wetlands Condition Assessment (NWCA), one of a series of water assessments being conducted by states, tribes, the U.S. Environmental Protection Agency (EPA), and other partners, surveyed over 900 wetland sites across the lower 48 states during Summer 2011. The NWCA ...

  20. Selecting radiotherapy dose distributions by means of constrained optimization problems.

    PubMed

    Alfonso, J C L; Buttazzo, G; García-Archilla, B; Herrero, M A; Núñez, L

    2014-05-01

    The main steps in planning radiotherapy consist in selecting for any patient diagnosed with a solid tumor (i) a prescribed radiation dose on the tumor, (ii) bounds on the radiation side effects on nearby organs at risk and (iii) a fractionation scheme specifying the number and frequency of therapeutic sessions during treatment. The goal of any radiotherapy treatment is to deliver on the tumor a radiation dose as close as possible to that selected in (i), while at the same time conforming to the constraints prescribed in (ii). To this day, considerable uncertainties remain concerning the best manner in which such issues should be addressed. In particular, the choice of a prescription radiation dose is mostly based on clinical experience accumulated on the particular type of tumor considered, without any direct reference to quantitative radiobiological assessment. Interestingly, mathematical models for the effect of radiation on biological matter have existed for quite some time, and are widely acknowledged by clinicians. However, the difficulty to obtain accurate in vivo measurements of the radiobiological parameters involved has severely restricted their direct application in current clinical practice.In this work, we first propose a mathematical model to select radiation dose distributions as solutions (minimizers) of suitable variational problems, under the assumption that key radiobiological parameters for tumors and organs at risk involved are known. Second, by analyzing the dependence of such solutions on the parameters involved, we then discuss the manner in which the use of those minimizers can improve current decision-making processes to select clinical dosimetries when (as is generally the case) only partial information on model radiosensitivity parameters is available. A comparison of the proposed radiation dose distributions with those actually delivered in a number of clinical cases strongly suggests that solutions of our mathematical model can be

  1. Simulation-optimization framework for multi-site multi-season hybrid stochastic streamflow modeling

    NASA Astrophysics Data System (ADS)

    Srivastav, Roshan; Srinivasan, K.; Sudheer, K. P.

    2016-11-01

    A simulation-optimization (S-O) framework is developed for the hybrid stochastic modeling of multi-site multi-season streamflows. The multi-objective optimization model formulated is the driver and the multi-site, multi-season hybrid matched block bootstrap model (MHMABB) is the simulation engine within this framework. The multi-site multi-season simulation model is the extension of the existing single-site multi-season simulation model. A robust and efficient evolutionary search based technique, namely, non-dominated sorting based genetic algorithm (NSGA - II) is employed as the solution technique for the multi-objective optimization within the S-O framework. The objective functions employed are related to the preservation of the multi-site critical deficit run sum and the constraints introduced are concerned with the hybrid model parameter space, and the preservation of certain statistics (such as inter-annual dependence and/or skewness of aggregated annual flows). The efficacy of the proposed S-O framework is brought out through a case example from the Colorado River basin. The proposed multi-site multi-season model AMHMABB (whose parameters are obtained from the proposed S-O framework) preserves the temporal as well as the spatial statistics of the historical flows. Also, the other multi-site deficit run characteristics namely, the number of runs, the maximum run length, the mean run sum and the mean run length are well preserved by the AMHMABB model. Overall, the proposed AMHMABB model is able to show better streamflow modeling performance when compared with the simulation based SMHMABB model, plausibly due to the significant role played by: (i) the objective functions related to the preservation of multi-site critical deficit run sum; (ii) the huge hybrid model parameter space available for the evolutionary search and (iii) the constraint on the preservation of the inter-annual dependence. Split-sample validation results indicate that the AMHMABB model is

  2. A Bayesian Framework for Landing Site Selection During Autonomous Spacecraft Descent

    NASA Technical Reports Server (NTRS)

    Serrano, Navid

    2006-01-01

    The success of a landed space exploration mission depends largely on the final landing site. Factors influencing site selection include safety, fuel-consumption, and scientific return. This paper addresses the problem of selecting the best available landing site based on these factors in real-time during autonomous spacecraft descent onto a planetary surface. The problem is modeled probabilistically using Bayesian Networks (BNs). BNs provide a means of representing the causal relationships between variables that impact the quality of a landing site. The final landing site is determined via probabilistic reasoning based on terrain safety derived from on-board sensors, available fuel based on spacecraft descent dynamics, and regions of interest defined by mission scientists.

  3. SEASAT: A satellite scatterometer illumination times of selected in situ sites

    NASA Technical Reports Server (NTRS)

    Schroeder, L. C.; Goodridge, D. R.; Boberly, J. C.; Hughes, J. K.; Sweet, J. L.

    1982-01-01

    A list of times that the SEASAT A Satellite Scatterometer (SASS) illuminated from directly above or directly abeam, selected surface sites where in situ winds were measured is provided. The list is ordered by the Greenwich Mean Time (GMT) of the midpoint of the illumination period (hit time) for a given surface site. The site identification, the orbit number and the direction from the subtrack in which the truth lies are provided. The accuracy of these times depends in part upon the ascending node times, which are estimated to be within +.1 sec, and on the illumination time relative to the ascending node, which is estimated to be within +6 seconds. The uncertainties in the times provided were judged to be sufficiently small to allow efficient and accurate extraction of SASS and in situ data at the selected surface sites. The list contains approximately six thousand hit times from 61 geographically dispersed sites.

  4. Structural characterization of the GSK-3beta active site using selective and non-selective ATP-mimetic inhibitors.

    PubMed

    Bertrand, J A; Thieffine, S; Vulpetti, A; Cristiani, C; Valsasina, B; Knapp, S; Kalisz, H M; Flocco, M

    2003-10-17

    GSK-3beta is a regulatory serine/threonine kinase with a plethora of cellular targets. Consequently, selective small molecule inhibitors of GSK-3beta may have a variety of therapeutic uses including the treatment of neurodegenerative diseases, type II diabetes and cancer. In order to characterize the active site of GSK-3beta, we determined crystal structures of unphosphorylated GSK-3beta in complex with selective and non-selective ATP-mimetic inhibitors. Analysis of the inhibitors' interactions with GSK-3beta in the structures reveals how the enzyme can accommodate a number of diverse molecular scaffolds. In addition, a conserved water molecule near Thr138 is identified that can serve a functional role in inhibitor binding. Finally, a comparison of the interactions made by selective and non-selective inhibitors highlights residues on the edge of the ATP binding-site that can be used to obtain inhibitor selectivity. Information gained from these structures provides a promising route for the design of second-generation GSK-3beta inhibitors.

  5. Multi-criteria site selection for fire services: the interaction with analytic hierarchy process and geographic information systems

    NASA Astrophysics Data System (ADS)

    Erden, T.; Coşkun, M. Z.

    2010-10-01

    This study combines AHP and GIS to provide decision makers with a model to ensure optimal site location(s) for fire stations selected. The roles of AHP and GIS in determining optimal locations are explained, criteria for site selection are outlined, and case study results for finding the optimal fire station locations in Istanbul, Turkey are included. The city of Istanbul has about 13 million residents and is the largest and most populated city in Turkey. The rapid and constant growth of Istanbul has resulted in the increased number of fire related cases. Fire incidents tend to increase year by year in parallel with city expansion, population and hazardous material facilities. Istanbul has seen a rise in reported fire incidents from 12 769 in 1994 to 30 089 in 2009 according to the interim report of Istanbul Metropolitan Municipality Department of Fire Brigade. The average response time was approximately 7 min 3 s in 2009. The goal of this study is to propose optimal sites for new fire station creation to allow the Fire Brigade in Istanbul to reduce the average response time to 5 min or less. After determining the necessity of suggesting additional fire stations, the following steps are taken into account: six criteria are considered in this analysis. They are: High Population Density (HPD); Proximity to Main Roads (PMR); Distance from Existing Fire Stations (DEF); Distance from Hazardous Material Facilities (DHM); Wooden Building Density (WBD); and Distance from the Areas Subjected to Earthquake Risk (DER). DHM criterion, with the weight of 40%, is the most important criterion in this analysis. The remaining criteria have a weight range from 9% to 16%. Moreover, the following steps are performed: representation of criterion map layers in GIS environment; classification of raster datasets; calculating the result raster map (suitability map for potential fire stations); and offering a model that supports decision makers in selecting fire station sites. The existing

  6. COMPARISON OF RANDOM AND SYSTEMATIC SITE SELECTION FOR ASSESSING ATTAINMENT OF AQUATIC LIFE USES IN SEGMENTS OF THE OHIO RIVER

    EPA Science Inventory

    This report is a description of field work and data analysis results comparing a design comparable to systematic site selection with one based on random selection of sites. The report is expected to validate the use of random site selection in the bioassessment program for the O...

  7. Control of ion selectivity in LeuT: two Na+ binding sites with two different mechanisms.

    PubMed

    Noskov, Sergei Y; Roux, Benoît

    2008-03-28

    The x-ray structure of LeuT, a bacterial homologue of Na(+)/Cl(-)-dependent neurotransmitter transporters, provides a great opportunity to better understand the molecular basis of monovalent cation selectivity in ion-coupled transporters. LeuT possesses two ion binding sites, NA1 and NA2, which are highly selective for Na(+). Extensive all-atom free-energy molecular dynamics simulations of LeuT embedded in an explicit membrane are performed at different temperatures and various occupancy states of the binding sites to dissect the molecular mechanism of ion selectivity. The results show that the two binding sites display robust selectivity for Na(+) over K(+) or Li(+), the competing ions of most similar radii. Of particular interest, the mechanism primarily responsible for selectivity for each of the two binding sites appears to be different. In NA1, selectivity for Na(+) over K(+) arises predominantly from the strong electrostatic field arising from the negatively charged carboxylate group of the leucine substrate coordinating the ion directly. In NA2, which comprises only neutral ligands, selectivity for Na(+) is enforced by the local structural restraints arising from the hydrogen-bonding network and the covalent connectivity of the polypeptide chain surrounding the ion according to a "snug-fit" mechanism.

  8. Application’s Method of Quadratic Programming for Optimization of Portfolio Selection

    NASA Astrophysics Data System (ADS)

    Kawamoto, Shigeru; Takamoto, Masanori; Kobayashi, Yasuhiro

    Investors or fund-managers face with optimization of portfolio selection, which means that determine the kind and the quantity of investment among several brands. We have developed a method to obtain optimal stock’s portfolio more rapidly from twice to three times than conventional method with efficient universal optimization. The method is characterized by quadratic matrix of utility function and constrained matrices divided into several sub-matrices by focusing on structure of these matrices.

  9. Optimization of gene sequences under constant mutational pressure and selection

    NASA Astrophysics Data System (ADS)

    Kowalczuk, M.; Gierlik, A.; Mackiewicz, P.; Cebrat, S.; Dudek, M. R.

    1999-12-01

    We have analyzed the influence of constant mutational pressure and selection on the nucleotide composition of DNA sequences of various size, which were represented by the genes of the Borrelia burgdorferi genome. With the help of MC simulations we have found that longer DNA sequences accumulate much less base substitutions per sequence length than short sequences. This leads us to the conclusion that the accuracy of replication may determine the size of genome.

  10. Optimal band selection for dimensionality reduction of hyperspectral imagery

    NASA Technical Reports Server (NTRS)

    Stearns, Stephen D.; Wilson, Bruce E.; Peterson, James R.

    1993-01-01

    Hyperspectral images have many bands requiring significant computational power for machine interpretation. During image pre-processing, regions of interest that warrant full examination need to be identified quickly. One technique for speeding up the processing is to use only a small subset of bands to determine the 'interesting' regions. The problem addressed here is how to determine the fewest bands required to achieve a specified performance goal for pixel classification. The band selection problem has been addressed previously Chen et al., Ghassemian et al., Henderson et al., and Kim et al.. Some popular techniques for reducing the dimensionality of a feature space, such as principal components analysis, reduce dimensionality by computing new features that are linear combinations of the original features. However, such approaches require measuring and processing all the available bands before the dimensionality is reduced. Our approach, adapted from previous multidimensional signal analysis research, is simpler and achieves dimensionality reduction by selecting bands. Feature selection algorithms are used to determine which combination of bands has the lowest probability of pixel misclassification. Two elements required by this approach are a choice of objective function and a choice of search strategy.

  11. Sensor Selection and Optimization for Health Assessment of Aerospace Systems

    NASA Technical Reports Server (NTRS)

    Maul, William A.; Kopasakis, George; Santi, Louis M.; Sowers, Thomas S.; Chicatelli, Amy

    2008-01-01

    Aerospace systems are developed similarly to other large-scale systems through a series of reviews, where designs are modified as system requirements are refined. For space-based systems few are built and placed into service these research vehicles have limited historical experience to draw from and formidable reliability and safety requirements, due to the remote and severe environment of space. Aeronautical systems have similar reliability and safety requirements, and while these systems may have historical information to access, commercial and military systems require longevity under a range of operational conditions and applied loads. Historically, the design of aerospace systems, particularly the selection of sensors, is based on the requirements for control and performance rather than on health assessment needs. Furthermore, the safety and reliability requirements are met through sensor suite augmentation in an ad hoc, heuristic manner, rather than any systematic approach. A review of the current sensor selection practice within and outside of the aerospace community was conducted and a sensor selection architecture is proposed that will provide a justifiable, defendable sensor suite to address system health assessment requirements.

  12. Sensor Selection and Optimization for Health Assessment of Aerospace Systems

    NASA Technical Reports Server (NTRS)

    Maul, William A.; Kopasakis, George; Santi, Louis M.; Sowers, Thomas S.; Chicatelli, Amy

    2007-01-01

    Aerospace systems are developed similarly to other large-scale systems through a series of reviews, where designs are modified as system requirements are refined. For space-based systems few are built and placed into service. These research vehicles have limited historical experience to draw from and formidable reliability and safety requirements, due to the remote and severe environment of space. Aeronautical systems have similar reliability and safety requirements, and while these systems may have historical information to access, commercial and military systems require longevity under a range of operational conditions and applied loads. Historically, the design of aerospace systems, particularly the selection of sensors, is based on the requirements for control and performance rather than on health assessment needs. Furthermore, the safety and reliability requirements are met through sensor suite augmentation in an ad hoc, heuristic manner, rather than any systematic approach. A review of the current sensor selection practice within and outside of the aerospace community was conducted and a sensor selection architecture is proposed that will provide a justifiable, dependable sensor suite to address system health assessment requirements.

  13. Selection of Inhibitor-Resistant Viral Potassium Channels Identifies a Selectivity Filter Site that Affects Barium and Amantadine Block

    PubMed Central

    Fujiwara, Yuichiro; Arrigoni, Cristina; Domigan, Courtney; Ferrara, Giuseppina; Pantoja, Carlos; Thiel, Gerhard; Moroni, Anna; Minor, Daniel L.

    2009-01-01

    Background Understanding the interactions between ion channels and blockers remains an important goal that has implications for delineating the basic mechanisms of ion channel function and for the discovery and development of ion channel directed drugs. Methodology/Principal Findings We used genetic selection methods to probe the interaction of two ion channel blockers, barium and amantadine, with the miniature viral potassium channel Kcv. Selection for Kcv mutants that were resistant to either blocker identified a mutant bearing multiple changes that was resistant to both. Implementation of a PCR shuffling and backcrossing procedure uncovered that the blocker resistance could be attributed to a single change, T63S, at a position that is likely to form the binding site for the inner ion in the selectivity filter (site 4). A combination of electrophysiological and biochemical assays revealed a distinct difference in the ability of the mutant channel to interact with the blockers. Studies of the analogous mutation in the mammalian inward rectifier Kir2.1 show that the T→S mutation affects barium block as well as the stability of the conductive state. Comparison of the effects of similar barium resistant mutations in Kcv and Kir2.1 shows that neighboring amino acids in the Kcv selectivity filter affect blocker binding. Conclusions/Significance The data support the idea that permeant ions have an integral role in stabilizing potassium channel structure, suggest that both barium and amantadine act at a similar site, and demonstrate how genetic selections can be used to map blocker binding sites and reveal mechanistic features. PMID:19834614

  14. Selection of optimal composition-control parameters for friable materials

    SciTech Connect

    Pak, Yu.N.; Vdovkin, A.V.

    1988-05-01

    A method for composition analysis of coal and minerals is proposed which uses scattered gamma radiation and does away with preliminary sample preparation to ensure homogeneous particle density, surface area, and size. Reduction of the error induced by material heterogeneity has previously been achieved by rotation of the control object during analysis. A further refinement is proposed which addresses the necessity that the contribution of the radiation scattered from each individual surface to the total intensity be the same. This is achieved by providing a constant linear rate of travel for the irradiated spot through back-and-forth motion of the sensor. An analytical expression is given for the laws of motion for the sensor and test tube which provides for uniform irradiated area movement along a path analogous to the Archimedes spiral. The relationships obtained permit optimization of measurement parameters in analyzing friable materials which are not uniform in grain size.

  15. A method to optimize selection on multiple identified quantitative trait loci

    PubMed Central

    Chakraborty, Reena; Moreau, Laurence; Dekkers, Jack CM

    2002-01-01

    A mathematical approach was developed to model and optimize selection on multiple known quantitative trait loci (QTL) and polygenic estimated breeding values in order to maximize a weighted sum of responses to selection over multiple generations. The model allows for linkage between QTL with multiple alleles and arbitrary genetic effects, including dominance, epistasis, and gametic imprinting. Gametic phase disequilibrium between the QTL and between the QTL and polygenes is modeled but polygenic variance is assumed constant. Breeding programs with discrete generations, differential selection of males and females and random mating of selected parents are modeled. Polygenic EBV obtained from best linear unbiased prediction models can be accommodated. The problem was formulated as a multiple-stage optimal control problem and an iterative approach was developed for its solution. The method can be used to develop and evaluate optimal strategies for selection on multiple QTL for a wide range of situations and genetic models. PMID:12081805

  16. Site-selective and stereoselective functionalization of unactivated C-H bonds

    NASA Astrophysics Data System (ADS)

    Liao, Kuangbiao; Negretti, Solymar; Musaev, Djamaladdin G.; Bacsa, John; Davies, Huw M. L.

    2016-05-01

    The laboratory synthesis of complex organic molecules relies heavily on the introduction and manipulation of functional groups, such as carbon-oxygen or carbon-halogen bonds; carbon-hydrogen bonds are far less reactive and harder to functionalize selectively. The idea of C-H functionalization, in which C-H bonds are modified at will instead of the functional groups, represents a paradigm shift in the standard logic of organic synthesis. For this approach to be generally useful, effective strategies for site-selective C-H functionalization need to be developed. The most practical solutions to the site-selectivity problem rely on either intramolecular reactions or the use of directing groups within the substrate. A challenging, but potentially more flexible approach, would be to use catalyst control to determine which site in a particular substrate would be functionalized. Here we describe the use of dirhodium catalysts to achieve highly site-selective, diastereoselective and enantioselective C-H functionalization of n-alkanes and terminally substituted n-alkyl compounds. The reactions proceed in high yield, and functional groups such as halides, silanes and esters are compatible with this chemistry. These studies demonstrate that high site selectivity is possible in C-H functionalization reactions without the need for a directing or anchoring group present in the molecule.

  17. A framework for landfill site selection using geographic information systems and multi criteria decision making technique

    NASA Astrophysics Data System (ADS)

    Mat, Nur Azriati; Benjamin, Aida Mauziah; Abdul-Rahman, Syariza; Wibowo, Antoni

    2016-10-01

    The solid waste disposal is one of the facilities which can cause harm to human health and also contribute to severe environmental pollution if it is not properly managed. Therefore, an effective decision on a landfill site selection in order to identify the most suitable area as a new landfill is very important. Since 25 years ago, the integration of geographic information systems (GIS) and multi criteria decision analysis (MCDA) has drawn significant interest among researchers. This integrated technique is commonly used for land use planning and selecting a new landfill site is one of the plan. This paper proposes a framework of landfill site selection with a consideration of resource requirement. This framework is developed by using the integration of GIS and MCDA to identify an appropriate location for landfill siting. A list of selection criteria obtained from the literature considered in selecting the best landfill site is also presented. The results of this study could later be used to help the waste management team in developing an efficient solid waste management system.

  18. A Role for the Actin Cytoskeleton of Saccharomyces cerevisiae in Bipolar Bud-Site Selection

    PubMed Central

    Yang, Shirley; Ayscough, Kathryn R.; Drubin, David G.

    1997-01-01

    Saccharomyces cerevisiae cells select bud sites according to one of two predetermined patterns. MATa and MATα cells bud in an axial pattern, and MATa/α cells bud in a bipolar pattern. These budding patterns are thought to depend on the placement of spatial cues at specific sites in the cell cortex. Because cytoskeletal elements play a role in organizing the cytoplasm and establishing distinct plasma membrane domains, they are well suited for positioning bud-site selection cues. Indeed, the septin-containing neck filaments are crucial for establishing the axial budding pattern characteristic of MATa and MATα cells. In this study, we determined the budding patterns of cells carrying mutations in the actin gene or in genes encoding actin-associated proteins: MATa/α cells were defective in the bipolar budding pattern, but MATa and MATα cells still exhibit a normal axial budding pattern. We also observed that MATa/α actin cytoskeleton mutant daughter cells correctly position their first bud at the distal pole of the cell, but mother cells position their buds randomly. The actin cytoskeleton therefore functions in generation of the bipolar budding pattern and is required specifically for proper selection of bud sites in mother MATa/α cells. These observations and the results of double mutant studies support the conclusion that different rules govern bud-site selection in mother and daughter MATa/α cells. A defective bipolar budding pattern did not preclude an sla2-6 mutant from undergoing pseudohyphal growth, highlighting the central role of daughter cell bud-site selection cues in the formation of pseudohyphae. Finally, by examining the budding patterns of mad2-1 mitotic checkpoint mutants treated with benomyl to depolymerize their microtubules, we confirmed and extended previous evidence indicating that microtubules do not function in axial or bipolar bud-site selection. PMID:9008707

  19. Selection of nest-site habitat by interior least terns in relation to sandbar construction

    USGS Publications Warehouse

    Sherfy, Mark H.; Stucker, Jennifer H.; Buhl, Deborah A.

    2012-01-01

    Federally endangered interior least terns (Sternula antillarum) nest on bare or sparsely vegetated sandbars on midcontinent river systems. Loss of nesting habitat has been implicated as a cause of population declines, and managing these habitats is a major initiative in population recovery. One such initiative involves construction of mid-channel sandbars on the Missouri River, where natural sandbar habitat has declined in quantity and quality since the late 1990s. We evaluated nest-site habitat selection by least terns on constructed and natural sandbars by comparing vegetation, substrate, and debris variables at nest sites (n = 798) and random points (n = 1,113) in bare or sparsely vegetated habitats. Our logistic regression models revealed that a broader suite of habitat features was important in nest-site selection on constructed than on natural sandbars. Odds ratios for habitat variables indicated that avoidance of habitat features was the dominant nest-site selection process on both sandbar types, with nesting terns being attracted to nest-site habitat features (gravel and debris) and avoiding vegetation only on constructed sandbars, and avoiding silt and leaf litter on both sandbar types. Despite the seemingly uniform nature of these habitats, our results suggest that a complex suite of habitat features influences nest-site choice by least terns. However, nest-site selection in this social, colonially nesting species may be influenced by other factors, including spatial arrangement of bare sand habitat, proximity to other least terns, and prior habitat occupancy by piping plovers (Charadrius melodus). We found that nest-site selection was sensitive to subtle variation in habitat features, suggesting that rigor in maintaining habitat condition will be necessary in managing sandbars for the benefit of least terns. Further, management strategies that reduce habitat features that are avoided by least terns may be the most beneficial to nesting least terns.

  20. Selection of nest-site habitat by interior least terns in relation to sandbar construction

    USGS Publications Warehouse

    Sherfy, M.H.; Stucker, J.H.; Buhl, D.A.

    2012-01-01

    Federally endangered interior least terns (Sternula antillarum) nest on bare or sparsely vegetated sandbars on midcontinent river systems. Loss of nesting habitat has been implicated as a cause of population declines, and managing these habitats is a major initiative in population recovery. One such initiative involves construction of mid-channel sandbars on the Missouri River, where natural sandbar habitat has declined in quantity and quality since the late 1990s. We evaluated nest-site habitat selection by least terns on constructed and natural sandbars by comparing vegetation, substrate, and debris variables at nest sites (na =a 798) and random points (na =a 1,113) in bare or sparsely vegetated habitats. Our logistic regression models revealed that a broader suite of habitat features was important in nest-site selection on constructed than on natural sandbars. Odds ratios for habitat variables indicated that avoidance of habitat features was the dominant nest-site selection process on both sandbar types, with nesting terns being attracted to nest-site habitat features (gravel and debris) and avoiding vegetation only on constructed sandbars, and avoiding silt and leaf litter on both sandbar types. Despite the seemingly uniform nature of these habitats, our results suggest that a complex suite of habitat features influences nest-site choice by least terns. However, nest-site selection in this social, colonially nesting species may be influenced by other factors, including spatial arrangement of bare sand habitat, proximity to other least terns, and prior habitat occupancy by piping plovers (Charadrius melodus). We found that nest-site selection was sensitive to subtle variation in habitat features, suggesting that rigor in maintaining habitat condition will be necessary in managing sandbars for the benefit of least terns. Further, management strategies that reduce habitat features that are avoided by least terns may be the most beneficial to nesting least terns

  1. Site selection in global clinical trials in patients hospitalized for heart failure: perceived problems and potential solutions

    PubMed Central

    Vaduganathan, Muthiah; Greene, Stephen J.; Mentz, Robert J.; Adams, Kirkwood F.; Anker, Stefan D.; Arnold, Malcolm; Baschiera, Fabio; Cleland, John G. F.; Cotter, Gadi; Fonarow, Gregg C.; Giordano, Christopher; Metra, Marco; Misselwitz, Frank; Mühlhofer, Eva; Nodari, Savina; Peacock, W. Frank; Pieske, Burkert M.; Sabbah, Hani N.; Sato, Naoki; Shah, Monica R.; Stockbridge, Norman L.; Teerlink, John R.; van Veldhuisen, Dirk J.; Zalewski, Andrew; Zannad, Faiez; Butler, Javed

    2014-01-01

    There are over 1 million hospitalizations for heart failure (HF) annually in the United States alone, and a similar number has been reported in Europe. Recent clinical trials investigating novel therapies in patients with hospitalized HF (HHF) have been negative, and the post-discharge event rate remains unacceptably high. The lack of success with HHF trials stem from problems with understanding the study drug, matching the drug to the appropriate HF subgroup, and study execution. Related to the concept of study execution is the importance of including appropriate study sites in HHF trials. Often overlooked issues include consideration of the geographic region and the number of patients enrolled at each study center. Marked differences in baseline patient co-morbidities, serum biomarkers, treatment utilization and outcomes have been demonstrated across geographic regions. Furthermore, patients from sites with low recruitment may have worse outcomes compared to sites with higher enrollment patterns. Consequently, sites with poor trial enrollment may influence key patient end points and likely do not justify the costs of site training and maintenance. Accordingly, there is an unmet need to develop strategies to identify the right study sites that have acceptable patient quantity and quality. Potential approaches include, but are not limited to, establishing a pre-trial registry, developing site performance metrics, identifying a local regionally involved leader and bolstering recruitment incentives. This manuscript summarizes the roundtable discussion hosted by the Food and Drug Administration between members of academia, the National Institutes of Health, industry partners, contract research organizations and academic research organizations on the importance of selecting optimal sites for successful trials in HHF. PMID:23099992

  2. Positive selection neighboring functionally essential sites and disease-implicated regions of mammalian reproductive proteins

    PubMed Central

    2010-01-01

    Background Reproductive proteins are central to the continuation of all mammalian species. The evolution of these proteins has been greatly influenced by environmental pressures induced by pathogens, rival sperm, sexual selection and sexual conflict. Positive selection has been demonstrated in many of these proteins with particular focus on primate lineages. However, the mammalia are a diverse group in terms of mating habits, population sizes and germ line generation times. We have examined the selective pressures at work on a number of novel reproductive proteins across a wide variety of mammalia. Results We show that selective pressures on reproductive proteins are highly varied. Of the 10 genes analyzed in detail, all contain signatures of positive selection either across specific sites or in specific lineages or a combination of both. Our analysis of SP56 and Col1a1 are entirely novel and the results show positively selected sites present in each gene. Our findings for the Col1a1 gene are suggestive of a link between positive selection and severe disease type. We find evidence in our dataset to suggest that interacting proteins are evolving in symphony: most likely to maintain interacting functionality. Conclusion Our in silico analyses show positively selected sites are occurring near catalytically important regions suggesting selective pressure to maximize efficient fertilization. In those cases where a mechanism of protein function is not fully understood, the sites presented here represent ideal candidates for mutational study. This work has highlighted the widespread rate heterogeneity in mutational rates across the mammalia and specifically has shown that the evolution of reproductive proteins is highly varied depending on the species and interacting partners. We have shown that positive selection and disease are closely linked in the Col1a1 gene. PMID:20149245

  3. Selection of spawning sites by coho salmon in a northern California stream

    USGS Publications Warehouse

    Mull, K.E.; Wilzbach, M.A.

    2007-01-01

    We assessed the relative importance of various factors contributing to spawning site use by a population of threatened coho salmon Oncorhynchus kisutch in Freshwater Creek, California, and created a predictive model of spawning habitat selection based on logistic regression analysis. We excluded sampling sites that previous studies had established as unsuitable on the basis of depth and substrate criteria and asked why fish chose particular locations and not others in seemingly suitable habitat. We evaluated surface water velocity, depth, substrate size composition, gravel inflow rates, vertical hydraulic gradient, geomorphic channel units, hyporheic water physicochemistry, cover, and proximity to other redds not in sampling sites during the 2004-2005 spawning season. In univariate comparisons with unused sites, coho salmon selected sites with a smaller median particle diameter, a larger percentage of gravel-pebble substrate, and higher gravel inflow rates. Based on multivariate logistic regression, the probability of a site's being used for spawning was best modeled as a positive function of the gravel-pebble fraction of the substrate, location at a pool or run tail, and the presence of existing redds in close proximity to the site. This model explained 38% of the variation in the data and was a better predictor of spawning habitat use than a more traditional model based on depth, velocity, and substrate. Our results highlight the potential importance of social behavior in contributing to habitat selection by spawning salmonids. ?? Copyright by the American Fisheries Society 2007.

  4. Optimizing drug exposure to minimize selection of antibiotic resistance.

    PubMed

    Olofsson, Sara K; Cars, Otto

    2007-09-01

    The worldwide increase in antibiotic resistance is a concern for public health. The fact that the choice of dose and treatment duration can affect the selection of antibiotic-resistant mutants is becoming more evident, and an increased number of studies have used pharmacodynamic models to describe the drug exposure and pharmacodynamic breakpoints needed to minimize and predict the development of resistance. However, there remains a lack of sufficient data, and future work is needed to fully characterize these target drug concentrations. More knowledge is also needed of drug pharmacodynamics versus bacteria with different resistance mutations and susceptibility levels. The dosing regimens should exhibit high efficacy not only against susceptible wild-type bacteria but, preferably, also against mutated bacteria that may exist in low numbers in "susceptible" populations. Thus, to prolong the life span of existing and new antibiotics, it is important that dosing regimens be carefully selected on the basis of pharmacokinetic and pharmacodynamic properties that prevent emergence of preexisting and newly formed mutants.

  5. Stationary phase optimized selectivity liquid chromatography: Basic possibilities of serially connected columns using the "PRISMA" principle.

    PubMed

    Nyiredy, Sz; Szucs, Zoltán; Szepesy, L

    2007-07-20

    A new procedure (stationary phase optimized selectivity liquid chromatography: SOS-LC) is described for the optimization of the HPLC stationary phase, using serially connected columns and the principle of the "PRISMA" model. The retention factors (k) of the analytes were determined on three different stationary phases. By use of these data the k values were predicted applying theoretically combined stationary phases. These predictions resulted in numerous intermediate theoretical separations from among which only the optimal one was assembled and tested. The overall selectivity of this separation was better than that of any individual base stationary phase. SOS-LC is independent of the mechanism and the scale of separation.

  6. Research on solving the optimal sizing and siting of distributed generation

    NASA Astrophysics Data System (ADS)

    Wang, Bo

    2017-01-01

    In this paper, a distributed network planning model is proposed with the goal of minimizing the sum of distributed power investment cost, network loss and interruption cost. In order to compare the performance of differential evolution algorithm (DE) and genetic algorithm (GA) in solving the optimal sizing and siting of distributed generation in distribution networks, the two algorithms were adopted to optimize the capacities and positions of DGs. Through analysis on a 10-bus test system, the study results show that the proposed model and algorithm can get reasonable planning scheme. And in solving simple optimization problems, both GA and DE Algorithms can get good results, but compare to DE, GA is of slow convergence speed and the convergence process is not quite stable.

  7. Particle swarm optimizer for weighting factor selection in intensity-modulated radiation therapy optimization algorithms.

    PubMed

    Yang, Jie; Zhang, Pengcheng; Zhang, Liyuan; Shu, Huazhong; Li, Baosheng; Gui, Zhiguo

    2017-01-01

    In inverse treatment planning of intensity-modulated radiation therapy (IMRT), the objective function is typically the sum of the weighted sub-scores, where the weights indicate the importance of the sub-scores. To obtain a high-quality treatment plan, the planner manually adjusts the objective weights using a trial-and-error procedure until an acceptable plan is reached. In this work, a new particle swarm optimization (PSO) method which can adjust the weighting factors automatically was investigated to overcome the requirement of manual adjustment, thereby reducing the workload of the human planner and contributing to the development of a fully automated planning process. The proposed optimization method consists of three steps. (i) First, a swarm of weighting factors (i.e., particles) is initialized randomly in the search space, where each particle corresponds to a global objective function. (ii) Then, a plan optimization solver is employed to obtain the optimal solution for each particle, and the values of the evaluation functions used to determine the particle's location and the population global location for the PSO are calculated based on these results. (iii) Next, the weighting factors are updated based on the particle's location and the population global location. Step (ii) is performed alternately with step (iii) until the termination condition is reached. In this method, the evaluation function is a combination of several key points on the dose volume histograms. Furthermore, a perturbation strategy - the crossover and mutation operator hybrid approach - is employed to enhance the population diversity, and two arguments are applied to the evaluation function to improve the flexibility of the algorithm. In this study, the proposed method was used to develop IMRT treatment plans involving five unequally spaced 6MV photon beams for 10 prostate cancer cases. The proposed optimization algorithm yielded high-quality plans for all of the cases, without human

  8. Determination of an Optimal Recruiting-Selection Strategy to Fill a Specified Quota of Satisfactory Personnel.

    ERIC Educational Resources Information Center

    Sands, William A.

    Managers of military and civilian personnel systems justifiably demand an estimate of the payoff in dollars and cents, which can be expected to result from the implementation of a proposed selection program. The Cost of Attaining Personnel Requirements (CAPER) Model provides an optimal recruiting-selection strategy for personnel decisions which…

  9. SLOPE—ADAPTIVE VARIABLE SELECTION VIA CONVEX OPTIMIZATION

    PubMed Central

    Bogdan, Małgorzata; van den Berg, Ewout; Sabatti, Chiara; Su, Weijie; Candès, Emmanuel J.

    2015-01-01

    We introduce a new estimator for the vector of coefficients β in the linear model y = Xβ + z, where X has dimensions n × p with p possibly larger than n. SLOPE, short for Sorted L-One Penalized Estimation, is the solution to minb∈ℝp12‖y−Xb‖ℓ22+λ1|b|(1)+λ2|b|(2)+⋯+λp|b|(p),where λ1 ≥ λ2 ≥ … ≥ λp ≥ 0 and |b|(1)≥|b|(2)≥⋯≥|b|(p) are the decreasing absolute values of the entries of b. This is a convex program and we demonstrate a solution algorithm whose computational complexity is roughly comparable to that of classical ℓ1 procedures such as the Lasso. Here, the regularizer is a sorted ℓ1 norm, which penalizes the regression coefficients according to their rank: the higher the rank—that is, stronger the signal—the larger the penalty. This is similar to the Benjamini and Hochberg [J. Roy. Statist. Soc. Ser. B 57 (1995) 289–300] procedure (BH) which compares more significant p-values with more stringent thresholds. One notable choice of the sequence {λi} is given by the BH critical values λBH(i)=z(1−i⋅q/2p), where q ∈ (0, 1) and z(α) is the quantile of a standard normal distribution. SLOPE aims to provide finite sample guarantees on the selected model; of special interest is the false discovery rate (FDR), defined as the expected proportion of irrelevant regressors among all selected predictors. Under orthogonal designs, SLOPE with λBH provably controls FDR at level q. Moreover, it also appears to have appreciable inferential properties under more general designs X while having substantial power, as demonstrated in a series of experiments running on both simulated and real data. PMID:26709357

  10. Ethical, social, and cultural considerations for site selection for research with genetically modified mosquitoes.

    PubMed

    Lavery, James V; Harrington, Laura C; Scott, Thomas W

    2008-09-01

    Recent advances in technology have made strategies for disease control using genetically modified (GM) vectors more plausible. Selecting an appropriate field site for research with GM mosquitoes may be one of the most complex and significant aspects of the research process. Among the key considerations of the process is the need to address ethical, legal, and cultural (ESC) issues. No guidelines have been developed to date for this complicated and sensitive process. In this paper, we describe a site selection process and a set of preliminary considerations for addressing the ESC aspects of a research program involving genetic strategies for the control of mosquitoes as vectors for dengue viruses. These considerations reflect some of the key ESC issues for site selection decisions for research with GM vectors.

  11. Phylogenetic analysis and positive-selection site detecting of vascular endothelial growth factor family in vertebrates.

    PubMed

    He, Wenwu; Tang, Yanyan; Qi, Bin; Lu, Chuansen; Qin, Chao; Wei, Yunfei; Yi, Jiachao; Chen, Mingwu

    2014-02-10

    Vascular endothelial growth factor (VEGF), known to play an important role in vascular homeostasis, vascular integrity and angiogenesis, is little known about the evolutionary relationship of its five members especially the role of gene duplication and natural selection in the evolution of the VEGF family. In this study, seventy-five full-length cDNA sequences from 33 vertebrate species were extracted from the NCBI's GenBank, UniProt protein database and the Ensembl database. By phylogenetic analyses, we investigated the origin, conservation, and evolution of the VEGFs. Five VEGF family members in vertebrates might be formed by gene duplication. The inferred evolutionary transitions that separate members which belong to different gene clusters correlated with changes in functional properties. Selection analysis and protein structure analysis were combined to explain the relationship of the site-specific evolution in the vertebrate VEGF family. Eleven positive selection sites, one transmembrane region and the active sites were detected in this process.

  12. MEDock: a web server for efficient prediction of ligand binding sites based on a novel optimization algorithm.

    PubMed

    Chang, Darby Tien-Hau; Oyang, Yen-Jen; Lin, Jung-Hsin

    2005-07-01

    The prediction of ligand binding sites is an essential part of the drug discovery process. Knowing the location of binding sites greatly facilitates the search for hits, the lead optimization process, the design of site-directed mutagenesis experiments and the hunt for structural features that influence the selectivity of binding in order to minimize the drug's adverse effects. However, docking is still the rate-limiting step for such predictions; consequently, much more efficient algorithms are required. In this article, the design of the MEDock web server is described. The goal of this sever is to provide an efficient utility for predicting ligand binding sites. The MEDock web server incorporates a global search strategy that exploits the maximum entropy property of the Gaussian probability distribution in the context of information theory. As a result of the global search strategy, the optimization algorithm incorporated in MEDock is significantly superior when dealing with very rugged energy landscapes, which usually have insurmountable barriers. This article describes four different benchmark cases that span a diverse set of different types of ligand binding interactions. These benchmarks were compared with the use of the Lamarckian genetic algorithm (LGA), which is the major workhorse of the well-known AutoDock program. These results demonstrate that MEDock consistently converged to the correct binding modes with significantly smaller numbers of energy evaluations than the LGA required. When judged by a threshold of the number of energy evaluations consumed in the docking simulation, MEDock also greatly elevates the rate of accurate predictions for all benchmark cases. MEDock is available at http://medock.csie.ntu.edu.tw/ and http://bioinfo.mc.ntu.edu.tw/medock/.

  13. A Multi-Step Assessment Scheme for Seismic Network Site Selection in Densely Populated Areas

    NASA Astrophysics Data System (ADS)

    Plenkers, Katrin; Husen, Stephan; Kraft, Toni

    2015-10-01

    We developed a multi-step assessment scheme for improved site selection during seismic network installation in densely populated areas. Site selection is a complex process where different aspects (seismic background noise, geology, and financing) have to be taken into account. In order to improve this process, we developed a step-wise approach that allows quantifying the quality of a site by using, in addition to expert judgement and test measurements, two weighting functions as well as reference stations. Our approach ensures that the recording quality aimed for is reached and makes different sites quantitatively comparable to each other. Last but not least, it is an easy way to document the decision process, because all relevant parameters are listed, quantified, and weighted.

  14. Selection for optimal crew performance - Relative impact of selection and training

    NASA Technical Reports Server (NTRS)

    Chidester, Thomas R.

    1987-01-01

    An empirical study supporting Helmreich's (1986) theoretical work on the distinct manner in which training and selection impact crew coordination is presented. Training is capable of changing attitudes, while selection screens for stable personality characteristics. Training appears least effective for leadership, an area strongly influenced by personality. Selection is least effective for influencing attitudes about personal vulnerability to stress, which appear to be trained in resource management programs. Because personality correlates with attitudes before and after training, it is felt that selection may be necessary even with a leadership-oriented training cirriculum.

  15. Polarized Growth Controls Cell Shape and Bipolar Bud Site Selection in Saccharomyces cerevisiae

    PubMed Central

    Sheu, Yi-Jun; Barral, Yves; Snyder, Michael

    2000-01-01

    We examined the relationship between polarized growth and division site selection, two fundamental processes important for proper development of eukaryotes. Diploid Saccharomyces cerevisiae cells exhibit an ellipsoidal shape and a specific division pattern (a bipolar budding pattern). We found that the polarity genes SPA2, PEA2, BUD6, and BNI1 participate in a crucial step of bud morphogenesis, apical growth. Deleting these genes results in round cells and diminishes bud elongation in mutants that exhibit pronounced apical growth. Examination of distribution of the polarized secretion marker Sec4 demonstrates that spa2Δ, pea2Δ, bud6Δ, and bni1Δ mutants fail to concentrate Sec4 at the bud tip during apical growth and at the division site during repolarization just prior to cytokinesis. Moreover, cell surface expansion is not confined to the distal tip of the bud in these mutants. In addition, we found that the p21-activated kinase homologue Ste20 is also important for both apical growth and bipolar bud site selection. We further examined how the duration of polarized growth affects bipolar bud site selection by using mutations in cell cycle regulators that control the timing of growth phases. The grr1Δ mutation enhances apical growth by stabilizing G1 cyclins and increases the distal-pole budding in diploids. Prolonging polarized growth phases by disrupting the G2/M cyclin gene CLB2 enhances the accuracy of bud site selection in wild-type, spa2Δ, and ste20Δ cells, whereas shortening the polarized growth phases by deleting SWE1 decreases the fidelity of bipolar budding. This study reports the identification of components required for apical growth and demonstrates the critical role of polarized growth in bipolar bud site selection. We propose that apical growth and repolarization at the site of cytokinesis are crucial for establishing spatial cues used by diploid yeast cells to position division planes. PMID:10866679

  16. The role of wood hardness in limiting nest site selection in avian cavity excavators.

    PubMed

    Lorenz, Teresa J; Vierling, Kerri T; Johnson, Timothy R; Fischer, Philip C

    2015-06-01

    Woodpeckers and other primary cavity excavators (PCEs) are important worldwide for excavating cavities in trees, and a large number of studies have examined their nesting preferences. However, quantitative measures of wood hardness have been omitted from most studies, and ecologists have focused on the effects of external tree- and habitat-level features on nesting. Moreover, information is lacking on the role of wood hardness in limiting nesting opportunities for this important guild. Here, we used an information theoretic approach to examine the role of wood hardness in multi-scale nest site selection and in limiting nesting opportunities for six species of North American PCEs. We found that interior wood hardness at nests (n = 259) differed from that at random sites, and all six species of PCE had nests with significantly softer interior wood than random trees (F1,517 = 106.15, P < 0.0001). Accordingly, interior wood hardness was the most influential factor in our models of nest site selection at both spatial scales that we examined: in the selection of trees within territories and in the selection of nest locations on trees. Moreover, regardless of hypothesized excavation abilities, all the species in our study appeared constrained by interior wood hardness, and only 4-14% of random sites were actually suitable for nesting. Our findings suggest that past studies that did not measure wood hardness counted many sites as available to PCEs when they were actually unsuitable, potentially biasing results. Moreover, by not accounting for nest site limitations in PCEs, managers may overestimate the amount of suitable habitat. We therefore urge ecologists to incorporate quantitative measures of wood hardness into PCE nest site selection studies, and to consider the limitations faced by avian cavity excavators in forest management decisions.

  17. Uncertainty based optimal monitoring network design for a chlorinated hydrocarbon contaminated site.

    PubMed

    Chadalavada, Sreenivasulu; Datta, Bithin; Naidu, Ravi

    2011-02-01

    An application of a newly developed optimal monitoring network for the delineation of contaminants in groundwater is demonstrated in this study. Designing a monitoring network in an optimal manner helps to delineate the contaminant plume with a minimum number of monitoring wells at optimal locations at a contaminated site. The basic principle used in this study is that the wells are installed where the measurement uncertainties are minimum at the potential monitoring locations. The development of the optimal monitoring network is based on the utilization of contaminant concentration data from an existing initial arbitrary monitoring network. The concentrations at the locations that were not sampled in the study area are estimated using geostatistical tools. The uncertainty in estimating the contaminant concentrations at such locations is used as design criteria for the optimal monitoring network. The uncertainty in the study area was quantified by using the concentration estimation variances at all the potential monitoring locations. The objective function for the monitoring network design minimizes the spatial concentration estimation variances at all potential monitoring well locations where a monitoring well is not to be installed as per the design criteria. In the proposed methodology, the optimal monitoring network is designed for the current management period and the contaminant concentration data estimated at the potential observation locations are then used as the input to the network design model. The optimal monitoring network is designed for the consideration of two different cases by assuming different initial arbitrary existing data. Three different scenarios depending on the limit of the maximum number of monitoring wells that can be allowed at any period are considered for each case. In order to estimate the efficiency of the developed optimal monitoring networks, mass estimation errors are compared for all the three different scenarios of the two

  18. Seeing the forest through the trees: Considering roost-site selection at multiple spatial scales

    USGS Publications Warehouse

    Jachowski, David S.; Rota, Christopher T.; Dobony, Christopher A.; Ford, W. Mark; Edwards, John W.

    2016-01-01

    Conservation of bat species is one of the most daunting wildlife conservation challenges in North America, requiring detailed knowledge about their ecology to guide conservation efforts. Outside of the hibernating season, bats in temperate forest environments spend their diurnal time in day-roosts. In addition to simple shelter, summer roost availability is as critical as maternity sites and maintaining social group contact. To date, a major focus of bat conservation has concentrated on conserving individual roost sites, with comparatively less focus on the role that broader habitat conditions contribute towards roost-site selection. We evaluated roost-site selection by a northern population of federally-endangered Indiana bats (Myotis sodalis) at Fort Drum Military Installation in New York, USA at three different spatial scales: landscape, forest stand, and individual tree level. During 2007–2011, we radiotracked 33 Indiana bats (10 males, 23 females) and located 348 roosting events in 116 unique roost trees. At the landscape scale, bat roost-site selection was positively associated with northern mixed forest, increased slope, and greater distance from human development. At the stand scale, we observed subtle differences in roost site selection based on sex and season, but roost selection was generally positively associated with larger stands with a higher basal area, larger tree diameter, and a greater sugar maple (Acer saccharum) component. We observed no distinct trends of roosts being near high-quality foraging areas of water and forest edges. At the tree scale, roosts were typically in American elm (Ulmus americana) or sugar maple of large diameter (>30 cm) of moderate decay with loose bark. Collectively, our results highlight the importance of considering day roost needs simultaneously across multiple spatial scales. Size and decay class of individual roosts are key ecological attributes for the Indiana bat, however, larger-scale stand structural

  19. Sleeping site selection by proboscis monkeys (Nasalis larvatus) in West Kalimantan, Indonesia.

    PubMed

    Feilen, Katie L; Marshall, Andrew J

    2014-12-01

    Primates spend at least half their lives sleeping; hence, sleeping site selection can have important effects on behavior and fitness. As proboscis monkeys (Nasalis larvatus) often sleep along rivers and form bands (aggregations of one male groups) at their sleeping sites, understanding sleeping site selection may shed light on two unusual aspects of this species' socioecology: their close association with rivers and their multilevel social organization. We studied sleeping site selection by proboscis monkeys for twelve months at Sungai Tolak, West Kalimantan, Indonesia to test two main hypotheses regarding the drivers of sleeping site selection: reduction of molestation by mosquitoes and anti-predator behavior. We identified to genus and collected data on the physical structure (diameter at breast height, relative height, branch structure, and leaf coverage) of sleeping trees and available trees in three forest types. We used resource selection function models to test specific predictions derived from our two hypotheses. The monkeys preferred to sleep in large trees with few canopy connections located along rivers. The selection of large emergent trees was consistent with both of our main hypotheses: decreased molestation by mosquitoes and reduced potential entry routes for terrestrial predators. Although we are only beginning to understand how sleeping sites might influence behavior, grouping, and potential survival of this species, our study has shown that proboscis monkeys (at Sungai Tolak) have a very strong preference for large trees located near the river. As these trees are often the first to be logged by local villagers, this may exacerbate the problems of forest loss for these endangered monkeys.

  20. Improving Water Quality in Construction Site Runoff: Optimal Mixing Time and Dose for Flocculating Suspended Sediment with Polyacrylamide

    NASA Astrophysics Data System (ADS)

    Zare, A. H.

    2015-12-01

    Sediment, a major water pollutant, can harm ecosystems and water resources. Sediment in construction site runoff can be controlled through flocculation using anionic, linear polyacrylamide (PAM), but there is little information on optimizing these applications. We conducted laboratory experiments to determine the optimal mixing times for varying concentrations of two types of polyacrylamide, APS 705 and FA 920, which are blends of polymers with a range of molecular weights that are anionic and neutral, respectively. These were selected from a variety of PAMs previously screened for flocculation potential. Soil from three active construction sites in the Piedmont region of North Carolina were used in the testing. A mixing speed of 300 revolutions per minute (RPM), the maximum available for the paddle mixer we used, was the most effective at reducing turbidity with PAM. Turbidity was reduced with increased mixing times up to a point, after which little additional benefit was evident. For all three soils tested, turbidity decreased as mixing time reached 1-2 minutes at polymer doses of 1, 5 and 10 mg L-1, with no substantial reduction with further mixing. At a polymer dose of 0.5 mg L-1, however, turbidity tended to increase beyond 5 minutes of mixing time, possibly because excessive shear forces destroyed sparsely linked floc. For both PAMs, 1 mg L-1 and a mixing time of 2-3 min appeared to be sufficient to achieve the most effective turbidity reduction.

  1. Methodology of research for qualitative composition of municipal solid waste to select an optimal method of recycling

    NASA Astrophysics Data System (ADS)

    Kravtsova, M. V.; Volkov, D. A.

    2015-09-01

    The article offers research methodology for qualitative composition of municipal solid waste to select an optimal method of recycling. The resource potential of waste directly depends on its composition and determines effectiveness of using various techniques, including separation and separate collection of refuge. The decision on re-equipment of waste-separating enterprise, which decreases the supply of waste to the burial site and provides economy of nonrenewable energy sources, is well-grounded, because it allows to diminish an anthropogenic load on environment.

  2. The surface chemistry of heterogeneous catalysis: mechanisms, selectivity, and active sites.

    PubMed

    Zaera, Francisco

    2005-01-01

    The role of chemical kinetics in defining the requirements for the active sites of heterogeneous catalysts is discussed. A personal view is presented, with specific examples from our laboratory to illustrate the role of the chemical composition, structure, and electronic properties of specific surface sites in determining reaction activity and selectivity. Manipulation of catalytic behavior via the addition of chemical modifiers and by tuning of the reaction conditions is also introduced.

  3. Geographical determination of an optimal network of landing sites for Hermes

    NASA Astrophysics Data System (ADS)

    Goester, J. F.

    Once its mission is done, Hermès will perform a deorbit burn, then will pilot towards a specially equipped landing site. As the atmospheric re-entry corridor is limited (the maximum cross range is 1500 km) Hermès will have to be situated on or-bits going near the runway. For safety reasons, we need to get one return opportunity per revolution, so it may be necessary to consider several landing sites and to fit out them. This proposed method allows to find, with easiness and quickness, the geographic areas getting the optimal solutions in term of number of runways, solutions amongst which we will choose already existing sites, checking other meteorologic, politic and economic constraints.

  4. On the complexity of discrete feature selection for optimal classification.

    PubMed

    Peña, Jose M; Nilsson, Roland

    2010-08-01

    Consider a classification problem involving only discrete features that are represented as random variables with some prescribed discrete sample space. In this paper, we study the complexity of two feature selection problems. The first problem consists in finding a feature subset of a given size k that has minimal Bayes risk. We show that for any increasing ordering of the Bayes risks of the feature subsets (consistent with an obvious monotonicity constraint), there exists a probability distribution that exhibits that ordering. This implies that solving the first problem requires an exhaustive search over the feature subsets of size k. The second problem consists of finding the minimal feature subset that has minimal Bayes risk. In the light of the complexity of the first problem, one may think that solving the second problem requires an exhaustive search over all of the feature subsets. We show that, under mild assumptions, this is not true. We also study the practical implications of our solutions to the second problem.

  5. Storage of human biospecimens: selection of the optimal storage temperature.

    PubMed

    Hubel, Allison; Spindler, Ralf; Skubitz, Amy P N

    2014-06-01

    Millions of biological samples are currently kept at low tempertures in cryobanks/biorepositories for long-term storage. The quality of the biospecimen when thawed, however, is not only determined by processing of the biospecimen but the storage conditions as well. The overall objective of this article is to describe the scientific basis for selecting a storage temperature for a biospecimen based on current scientific understanding. To that end, this article reviews some physical basics of the temperature, nucleation, and ice crystal growth present in biological samples stored at low temperatures (-20°C to -196°C), and our current understanding of the role of temperature on the activity of degradative molecules present in biospecimens. The scientific literature relevant to the stability of specific biomarkers in human fluid, cell, and tissue biospecimens is also summarized for the range of temperatures between -20°C to -196°C. These studies demonstrate the importance of storage temperature on the stability of critical biomarkers for fluid, cell, and tissue biospecimens.

  6. Applying optimal model selection in principal stratification for causal inference.

    PubMed

    Odondi, Lang'o; McNamee, Roseanne

    2013-05-20

    Noncompliance to treatment allocation is a key source of complication for causal inference. Efficacy estimation is likely to be compounded by the presence of noncompliance in both treatment arms of clinical trials where the intention-to-treat estimate provides a biased estimator for the true causal estimate even under homogeneous treatment effects assumption. Principal stratification method has been developed to address such posttreatment complications. The present work extends a principal stratification method that adjusts for noncompliance in two-treatment arms trials by developing model selection for covariates predicting compliance to treatment in each arm. We apply the method to analyse data from the Esprit study, which was conducted to ascertain whether unopposed oestrogen (hormone replacement therapy) reduced the risk of further cardiac events in postmenopausal women who survive a first myocardial infarction. We adjust for noncompliance in both treatment arms under a Bayesian framework to produce causal risk ratio estimates for each principal stratum. For mild values of a sensitivity parameter and using separate predictors of compliance in each arm, principal stratification results suggested that compliance with hormone replacement therapy only would reduce the risk for death and myocardial reinfarction by about 47% and 25%, respectively, whereas compliance with either treatment would reduce the risk for death by 13% and reinfarction by 60% among the most compliant. However, the results were sensitive to the user-defined sensitivity parameter.

  7. Plastic scintillation dosimetry: Optimal selection of scintillating fibers and scintillators

    SciTech Connect

    Archambault, Louis; Arsenault, Jean; Gingras, Luc; Sam Beddar, A.; Roy, Rene; Beaulieu, Luc

    2005-07-15

    Scintillation dosimetry is a promising avenue for evaluating dose patterns delivered by intensity-modulated radiation therapy plans or for the small fields involved in stereotactic radiosurgery. However, the increase in signal has been the goal for many authors. In this paper, a comparison is made between plastic scintillating fibers and plastic scintillator. The collection of scintillation light was measured experimentally for four commercial models of scintillating fibers (BCF-12, BCF-60, SCSF-78, SCSF-3HF) and two models of plastic scintillators (BC-400, BC-408). The emission spectra of all six scintillators were obtained by using an optical spectrum analyzer and they were compared with theoretical behavior. For scintillation in the blue region, the signal intensity of a singly clad scintillating fiber (BCF-12) was 120% of that of the plastic scintillator (BC-400). For the multiclad fiber (SCSF-78), the signal reached 144% of that of the plastic scintillator. The intensity of the green scintillating fibers was lower than that of the plastic scintillator: 47% for the singly clad fiber (BCF-60) and 77% for the multiclad fiber (SCSF-3HF). The collected light was studied as a function of the scintillator length and radius for a cylindrical probe. We found that symmetric detectors with nearly the same spatial resolution in each direction (2 mm in diameter by 3 mm in length) could be made with a signal equivalent to those of the more commonly used asymmetric scintillators. With augmentation of the signal-to-noise ratio in consideration, this paper presents a series of comparisons that should provide insight into selection of a scintillator type and volume for development of a medical dosimeter.

  8. Groundwater Monitoring Optimization of Post Closure Waste Sites at SRS - 13184

    SciTech Connect

    Ross, Jeff; O'Quinn, Sadika; Adams, Karen; Prater, Phil

    2013-07-01

    Groundwater monitoring at the Savannah River Site (SRS) is required at dozens of waste sites and includes sampling at over 1,000 monitoring wells. The expected longevity of groundwater contamination and associated groundwater monitoring and reporting constitutes a significant long-term cost that represents an increasing proportion of the environmental management budget as surface waste units are closed. Therefore, a comprehensive evaluation of the monitoring program for eighteen regulated waste units was conducted to identify areas where monitoring could be optimized. The units evaluated varied considerably in the scope of monitoring; ranging from two wells to hundreds of wells. In order to systematically evaluate such disparate monitoring networks, SRS developed a decision-logic analysis using flow sheets to address potential areas of optimization. Five areas were identified for evaluation, including: (1) Comparison of current monitoring to regulatory requirements, (2) Spatial distribution, (3) Temporal sampling, (4) Analyte requirements, and (5) Reporting frequency and content. Optimization recommendations were made for fifteen of the eighteen groundwater units. The spatial evaluation resulted in recommendations to suspend sampling in 79 wells and add sampling at 16 wells. The temporal evaluation resulted in recommendations to reduce the number of well visits per year by 504. Analyte reductions were recommended at three groundwater units, with increases at three other units. Reporting frequency reductions were recommended for five units. Approximately $700,000 (direct dollars) of potential annualized cost savings were identified for these groundwater units, provided all recommendations are approved. The largest area of savings was associated with reducing the reporting frequency. The optimization approach has been presented to the EPA and South Carolina Department of Environmental Control (SCHDEC), with unit-specific recommendations approved for all five units

  9. Visualization of multi-property landscapes for compound selection and optimization

    NASA Astrophysics Data System (ADS)

    de la Vega de León, Antonio; Kayastha, Shilva; Dimova, Dilyana; Schultz, Thomas; Bajorath, Jürgen

    2015-08-01

    Compound optimization generally requires considering multiple properties in concert and reaching a balance between them. Computationally, this process can be supported by multi-objective optimization methods that produce numerical solutions to an optimization task. Since a variety of comparable multi-property solutions are usually obtained further prioritization is required. However, the underlying multi-dimensional property spaces are typically complex and difficult to rationalize. Herein, an approach is introduced to visualize multi-property landscapes by adapting the concepts of star and parallel coordinates from computer graphics. The visualization method is designed to complement multi-objective compound optimization. We show that visualization makes it possible to further distinguish between numerically equivalent optimization solutions and helps to select drug-like compounds from multi-dimensional property spaces. The methodology is intuitive, applicable to a wide range of chemical optimization problems, and made freely available to the scientific community.

  10. Visualization of multi-property landscapes for compound selection and optimization.

    PubMed

    de la Vega de León, Antonio; Kayastha, Shilva; Dimova, Dilyana; Schultz, Thomas; Bajorath, Jürgen

    2015-08-01

    Compound optimization generally requires considering multiple properties in concert and reaching a balance between them. Computationally, this process can be supported by multi-objective optimization methods that produce numerical solutions to an optimization task. Since a variety of comparable multi-property solutions are usually obtained further prioritization is required. However, the underlying multi-dimensional property spaces are typically complex and difficult to rationalize. Herein, an approach is introduced to visualize multi-property landscapes by adapting the concepts of star and parallel coordinates from computer graphics. The visualization method is designed to complement multi-objective compound optimization. We show that visualization makes it possible to further distinguish between numerically equivalent optimization solutions and helps to select drug-like compounds from multi-dimensional property spaces. The methodology is intuitive, applicable to a wide range of chemical optimization problems, and made freely available to the scientific community.

  11. Urban Climate Station Site Selection Through Combined Digital Surface Model and Sun Angle Calculations

    NASA Technical Reports Server (NTRS)

    Kidd, Chris; Chapman, Lee

    2012-01-01

    Meteorological measurements within urban areas are becoming increasingly important due to the accentuating effects of climate change upon the Urban Heat Island (UHI). However, ensuring that such measurements are representative of the local area is often difficult due to the diversity of the urban environment. The evaluation of sites is important for both new sites and for the relocation of established sites to ensure that long term changes in the meteorological and climatological conditions continue to be faithfully recorded. Site selection is traditionally carried out in the field using both local knowledge and visual inspection. This paper exploits and assesses the use of lidar-derived digital surface models (DSMs) to quantitatively aid the site selection process. This is acheived by combining the DSM with a solar model, first to generate spatial maps of sky view factors and sun-hour potential and second, to generate site-specific views of the horizon. The results show that such a technique is a useful first-step approach to identify key sites that may be further evaluated for the location of meteorological stations within urban areas.

  12. Barium ions selectively activate BK channels via the Ca2+-bowl site.

    PubMed

    Zhou, Yu; Zeng, Xu-Hui; Lingle, Christopher J

    2012-07-10

    Activation of Ca(2+)-dependent BK channels is increased via binding of micromolar Ca(2+) to two distinct high-affinity sites per BK α-subunit. One site, termed the Ca(2+) bowl, is embedded within the second RCK domain (RCK2; regulator of conductance for potassium) of each α-subunit, while oxygen-containing residues in the first RCK domain (RCK1) have been linked to a separate Ca(2+) ligation site. Although both sites are activated by Ca(2+) and Sr(2+), Cd(2+) selectively favors activation via the RCK1 site. Divalent cations of larger ionic radius than Sr(2+) are thought to be ineffective at activating BK channels. Here we show that Ba(2+), better known as a blocker of K(+) channels, activates BK channels and that this effect arises exclusively from binding at the Ca(2+)-bowl site. Compared with previous estimates for Ca(2+) bowl-mediated activation by Ca(2+), the affinity of Ba(2+) to the Ca(2+) bowl is reduced about fivefold, and coupling of binding to activation is reduced from ∼3.6 for Ca(2+) to about ∼2.8 for Ba(2+). These results support the idea that ionic radius is an important determinant of selectivity differences among different divalent cations observed for each Ca(2+)-binding site.

  13. Waterbird nest-site selection is influenced by neighboring nests and island topography

    USGS Publications Warehouse

    Hartman, Christopher; Ackerman, Josh; Takekawa, John Y.; Herzog, Mark

    2016-01-01

    Avian nest-site selection is influenced by factors operating across multiple spatial scales. Identifying preferred physical characteristics (e.g., topography, vegetation structure) can inform managers to improve nesting habitat suitability. However, social factors (e.g., attraction, territoriality, competition) can complicate understanding physical characteristics preferred by nesting birds. We simultaneously evaluated the physical characteristics and social factors influencing selection of island nest sites by colonial-nesting American avocets (Recurvirostra americana) and Forster's terns (Sterna forsteri) at 2 spatial scales in San Francisco Bay, 2011–2012. At the larger island plot (1 m2) scale, we used real-time kinematics to produce detailed topographies of nesting islands and map the distribution of nests. Nesting probability was greatest in island plots between 0.5 m and 1.5 m above the water surface, at distances <10 m from the water's edge, and of moderately steep (avocets) or flat (terns) slopes. Further, avocet and tern nesting probability increased as the number of nests initiated in adjacent plots increased up to a peak of 11–12 tern nests, and then decreased thereafter. Yet, avocets were less likely to nest in plots adjacent to plots with nesting avocets, suggesting an influence of intra-specific territoriality. At the smaller microhabitat scale, or the area immediately surrounding the nest, we compared topography, vegetation, and distance to nearest nest between nest sites and paired random sites. Topography had little influence on selection of the nest microhabitat. Instead, nest sites were more likely to have vegetation present, and greater cover, than random sites. Finally, avocet, and to a lesser extent tern, nest sites were closer to other active conspecific or heterospecific nests than random sites, indicating that social attraction played a role in selection of nest microhabitat. Our results demonstrate key differences in nest-site

  14. Landfill site selection for municipal solid wastes in mountainous areas with landslide susceptibility.

    PubMed

    Eskandari, Mahnaz; Homaee, Mehdi; Falamaki, Amin

    2016-06-01

    Several cities across the world are located in mountainous and landslide prone areas. Any landfill siting without considering landslide susceptibility in such regions may impose additional environmental adversity. This study was aimed to propose a practical method for selecting waste disposal site that accounts for landslide exposure. The proposed method was applied to a city which is highly proneness to landslide due to its geology, morphology, and climatic conditions. First, information on the previously occurred landslides of the region was collected. Based on this information, proper landslide causative factors were selected and their thematic maps were prepared. Factors' classes were then standardized in 0-1 domain, and thematic layers were weighted by using analytical hierarchy process (AHP). The landslide susceptibility map was prepared afterwards. Unsuitable areas for landfill location were masked in GIS environment by Boolean method, retaining sufficient areas for further evaluation. Nine remaining alternatives were selected through comprehensive field visits and were ranked by using AHP. Consequently, 17 factors in three environmental, economical, and social perspectives were employed. Sensitivity analyses were performed to assess the stability of the alternatives ranking with respect to variations in criterion weights. Based on the obtained landslide susceptible map, nearly 36 % of the entire region is proneness to landslide. The prepared Boolean map indicates that potential areas for landfill construction cover 11 % of the whole region. The results further indicated that if landslide susceptible areas are not considered in landfill site selection, the potential landfill sites would become more than twice. It can be concluded that if any of these landslide prone sites are selected for landfilling, further environmental disaster would be terminated in the future. It can be further concluded that the proposed method could reasonably well be adjusted to

  15. Viking High-Resolution Topography and Mars '01 Site Selection: Application to the White Rock Area

    NASA Astrophysics Data System (ADS)

    Tanaka, K. L.; Kirk, Randolph L.; Mackinnon, D. J.; Howington-Kraus, E.

    1999-06-01

    Definition of the local topography of the Mars '01 Lander site is crucial for assessment of lander safety and rover trafficability. According to Golombek et al., steep surface slopes may (1) cause retro-rockets to be fired too early or late for a safe landing, (2) the landing site slope needs to be < 1deg to ensure lander stability, and (3) a nearly level site is better for power generation of both the lander and the rover and for rover trafficability. Presently available datasets are largely inadequate to determine surface slope at scales pertinent to landing-site issues. Ideally, a topographic model of the entire landing site at meter-scale resolution would permit the best assessment of the pertinent topographic issues. MOLA data, while providing highly accurate vertical measurements, are inadequate to address slopes along paths of less than several hundred meters, because of along-track data spacings of hundreds of meters and horizontal errors in positioning of 500 to 2000 m. The capability to produce stereotopography from MOC image pairs is not yet in hand, nor can we necessarily expect a suitable number of stereo image pairs to be acquired. However, for a limited number of sites, high-resolution Viking stereo imaging is available at tens of meters horizontal resolution, capable of covering landing-ellipse sized areas. Although we would not necessarily suggest that the chosen Mars '01 Lander site should be located where good Viking stereotopography is available, an assessment of typical surface slopes at these scales for a range of surface types may be quite valuable in landing-site selection. Thus this study has a two-fold application: (1) to support the proposal of White Rock as a candidate Mars '01 Lander site, and (2) to evaluate how Viking high resolution stereotopography may be of value in the overall Mars '01 Lander site selection process.

  16. Large-scale control site selection for population monitoring: an example assessing Sage-grouse trends

    USGS Publications Warehouse

    Fedy, Bradley C.; O'Donnell, Michael; Bowen, Zachary H.

    2015-01-01

    Human impacts on wildlife populations are widespread and prolific and understanding wildlife responses to human impacts is a fundamental component of wildlife management. The first step to understanding wildlife responses is the documentation of changes in wildlife population parameters, such as population size. Meaningful assessment of population changes in potentially impacted sites requires the establishment of monitoring at similar, nonimpacted, control sites. However, it is often difficult to identify appropriate control sites in wildlife populations. We demonstrated use of Geographic Information System (GIS) data across large spatial scales to select biologically relevant control sites for population monitoring. Greater sage-grouse (Centrocercus urophasianus; hearafter, sage-grouse) are negatively affected by energy development, and monitoring of sage-grouse population within energy development areas is necessary to detect population-level responses. Weused population data (1995–2012) from an energy development area in Wyoming, USA, the Atlantic Rim Project Area (ARPA), and GIS data to identify control sites that were not impacted by energy development for population monitoring. Control sites were surrounded by similar habitat and were within similar climate areas to the ARPA. We developed nonlinear trend models for both the ARPA and control sites and compared long-term trends from the 2 areas. We found little difference between the ARPA and control sites trends over time. This research demonstrated an approach for control site selection across large landscapes and can be used as a template for similar impact-monitoring studies. It is important to note that identification of changes in population parameters between control and treatment sites is only the first step in understanding the mechanisms that underlie those changes. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  17. A particle swarm optimization algorithm for beam angle selection in intensity-modulated radiotherapy planning.

    PubMed

    Li, Yongjie; Yao, Dezhong; Yao, Jonathan; Chen, Wufan

    2005-08-07

    Automatic beam angle selection is an important but challenging problem for intensity-modulated radiation therapy (IMRT) planning. Though many efforts have been made, it is still not very satisfactory in clinical IMRT practice because of overextensive computation of the inverse problem. In this paper, a new technique named BASPSO (Beam Angle Selection with a Particle Swarm Optimization algorithm) is presented to improve the efficiency of the beam angle optimization problem. Originally developed as a tool for simulating social behaviour, the particle swarm optimization (PSO) algorithm is a relatively new population-based evolutionary optimization technique first introduced by Kennedy and Eberhart in 1995. In the proposed BASPSO, the beam angles are optimized using PSO by treating each beam configuration as a particle (individual), and the beam intensity maps for each beam configuration are optimized using the conjugate gradient (CG) algorithm. These two optimization processes are implemented iteratively. The performance of each individual is evaluated by a fitness value calculated with a physical objective function. A population of these individuals is evolved by cooperation and competition among the individuals themselves through generations. The optimization results of a simulated case with known optimal beam angles and two clinical cases (a prostate case and a head-and-neck case) show that PSO is valid and efficient and can speed up the beam angle optimization process. Furthermore, the performance comparisons based on the preliminary results indicate that, as a whole, the PSO-based algorithm seems to outperform, or at least compete with, the GA-based algorithm in computation time and robustness. In conclusion, the reported work suggested that the introduced PSO algorithm could act as a new promising solution to the beam angle optimization problem and potentially other optimization problems in IMRT, though further studies need to be investigated.

  18. Coupling between protein level selection and codon usage optimization in the evolution of bacteria and archaea.

    PubMed

    Ran, Wenqi; Kristensen, David M; Koonin, Eugene V

    2014-03-25

    The relationship between the selection affecting codon usage and selection on protein sequences of orthologous genes in diverse groups of bacteria and archaea was examined by using the Alignable Tight Genome Clusters database of prokaryote genomes. The codon usage bias is generally low, with 57.5% of the gene-specific optimal codon frequencies (Fopt) being below 0.55. This apparent weak selection on codon usage contrasts with the strong purifying selection on amino acid sequences, with 65.8% of the gene-specific dN/dS ratios being below 0.1. For most of the genomes compared, a limited but statistically significant negative correlation between Fopt and dN/dS was observed, which is indicative of a link between selection on protein sequence and selection on codon usage. The strength of the coupling between the protein level selection and codon usage bias showed a strong positive correlation with the genomic GC content. Combined with previous observations on the selection for GC-rich codons in bacteria and archaea with GC-rich genomes, these findings suggest that selection for translational fine-tuning could be an important factor in microbial evolution that drives the evolution of genome GC content away from mutational equilibrium. This type of selection is particularly pronounced in slowly evolving, "high-status" genes. A significantly stronger link between the two aspects of selection is observed in free-living bacteria than in parasitic bacteria and in genes encoding metabolic enzymes and transporters than in informational genes. These differences might reflect the special importance of translational fine-tuning for the adaptability of gene expression to environmental changes. The results of this work establish the coupling between protein level selection and selection for translational optimization as a distinct and potentially important factor in microbial evolution. IMPORTANCE Selection affects the evolution of microbial genomes at many levels, including both

  19. Distributions of selectively constrained sites and deleterious mutation rates in the hominid and murid genomes.

    PubMed

    Eory, Lél; Halligan, Daniel L; Keightley, Peter D

    2010-01-01

    Protein-coding sequences make up only about 1% of the mammalian genome. Much of the remaining 99% has been long assumed to be junk DNA, with little or no functional significance. Here, we show that in hominids, a group with historically low effective population sizes, all classes of noncoding DNA evolve more slowly than ancestral transposable elements and so appear to be subject to significant evolutionary constraints. Under the nearly neutral theory, we expected to see lower levels of selective constraints on most sequence types in hominids than murids, a group that is thought to have a higher effective population size. We found that this is the case for many sequence types examined, the most extreme example being 5'UTRs, for which constraint in hominids is only about one-third that of murids. Surprisingly, however, we observed higher constraints for some sequence types in hominids, notably 4-fold sites, where constraint is more than twice as high as in murids. This implies that more than about one-fifth of mutations at 4-fold sites are effectively selected against in hominids. The higher constraint at 4-fold sites in hominids suggests a more complex protein-coding gene structure than murids and indicates that methods for detecting selection on protein-coding sequences (e.g., using the d(N)/d(S) ratio), with 4-fold sites as a neutral standard, may lead to biased estimates, particularly in hominids. Our constraint estimates imply that 5.4% of nucleotide sites in the human genome are subject to effective negative selection and that there are three times as many constrained sites within noncoding sequences as within protein-coding sequences. Including coding and noncoding sites, we estimate that the genomic deleterious mutation rate U = 4.2. The mutational load predicted under a multiplicative model is therefore about 99% in hominids.

  20. Patterns of bud-site selection in the yeast Saccharomyces cerevisiae

    PubMed Central

    1995-01-01

    Cells of the yeast Saccharomyces cerevisiae select bud sites in either of two distinct spatial patterns, known as axial (expressed by a and alpha cells) and bipolar (expressed by a/alpha cells). Fluorescence, time-lapse, and scanning electron microscopy have been used to obtain more precise descriptions of these patterns. From these descriptions, we conclude that in the axial pattern, the new bud forms directly adjacent to the division site in daughter cells and directly adjacent to the immediately preceding division site (bud site) in mother cells, with little influence from earlier sites. Thus, the division site appears to be marked by a spatial signal(s) that specifies the location of the new bud site and is transient in that it only lasts from one budding event to the next. Consistent with this conclusion, starvation and refeeding of axially budding cells results in the formation of new buds at nonaxial sites. In contrast, in bipolar budding cells, both poles are specified persistently as potential bud sites, as shown by the observations that a pole remains competent for budding even after several generations of nonuse and that the poles continue to be used for budding after starvation and refeeding. It appears that the specification of the two poles as potential bud sites occurs before a daughter cell forms its first bud, as a daughter can form this bud near either pole. However, there is a bias towards use of the pole distal to the division site. The strength of this bias varies from strain to strain, is affected by growth conditions, and diminishes in successive cell cycles. The first bud that forms near the distal pole appears to form at the very tip of the cell, whereas the first bud that forms near the pole proximal to the original division site (as marked by the birth scar) is generally somewhat offset from the tip and adjacent to (or overlapping) the birth scar. Subsequent buds can form near either pole and appear almost always to be adjacent either to

  1. High resolution x-ray fluorescence spectroscopy - a new technique for site- and spin-selectivity

    SciTech Connect

    Wang, Xin

    1996-12-01

    X-ray spectroscopy has long been used to elucidate electronic and structural information of molecules. One of the weaknesses of x-ray absorption is its sensitivity to all of the atoms of a particular element in a sample. Through out this thesis, a new technique for enhancing the site- and spin-selectivity of the x-ray absorption has been developed. By high resolution fluorescence detection, the chemical sensitivity of K emission spectra can be used to identify oxidation and spin states; it can also be used to facilitate site-selective X-ray Absorption Near Edge Structure (XANES) and site-selective Extended X-ray Absorption Fine Structure (EXAFS). The spin polarization in K fluorescence could be used to generate spin selective XANES or spin-polarized EXAFS, which provides a new measure of the spin density, or the nature of magnetic neighboring atoms. Finally, dramatic line-sharpening effects by the combination of absorption and emission processes allow observation of structure that is normally unobservable. All these unique characters can enormously simplify a complex x-ray spectrum. Applications of this novel technique have generated information from various transition-metal model compounds to metalloproteins. The absorption and emission spectra by high resolution fluorescence detection are interdependent. The ligand field multiplet model has been used for the analysis of K{alpha} and K{beta} emission spectra. First demonstration on different chemical states of Fe compounds has shown the applicability of site selectivity and spin polarization. Different interatomic distances of the same element in different chemical forms have been detected using site-selective EXAFS.

  2. Methane Adsorption on Aggregates of Fullerenes: Site-Selective Storage Capacities and Adsorption Energies

    PubMed Central

    Kaiser, Alexander; Zöttl, Samuel; Bartl, Peter; Leidlmair, Christian; Mauracher, Andreas; Probst, Michael; Denifl, Stephan; Echt, Olof; Scheier, Paul

    2013-01-01

    Methane adsorption on positively charged aggregates of C60 is investigated by both mass spectrometry and computer simulations. Calculated adsorption energies of 118–281 meV are in the optimal range for high-density storage of natural gas. Groove sites, dimple sites, and the first complete adsorption shells are identified experimentally and confirmed by molecular dynamics simulations, using a newly developed force field for methane–methane and fullerene–methane interaction. The effects of corrugation and curvature are discussed and compared with data for adsorption on graphite, graphene, and carbon nanotubes. PMID:23744834

  3. Methane adsorption on aggregates of fullerenes: site-selective storage capacities and adsorption energies.

    PubMed

    Kaiser, Alexander; Zöttl, Samuel; Bartl, Peter; Leidlmair, Christian; Mauracher, Andreas; Probst, Michael; Denifl, Stephan; Echt, Olof; Scheier, Paul

    2013-07-01

    Methane adsorption on positively charged aggregates of C60 is investigated by both mass spectrometry and computer simulations. Calculated adsorption energies of 118-281 meV are in the optimal range for high-density storage of natural gas. Groove sites, dimple sites, and the first complete adsorption shells are identified experimentally and confirmed by molecular dynamics simulations, using a newly developed force field for methane-methane and fullerene-methane interaction. The effects of corrugation and curvature are discussed and compared with data for adsorption on graphite, graphene, and carbon nanotubes.

  4. An intron element modulating 5' splice site selection in the hnRNP A1 pre-mRNA interacts with hnRNP A1.

    PubMed Central

    Chabot, B; Blanchette, M; Lapierre, I; La Branche, H

    1997-01-01

    The hnRNP A1 pre-mRNA is alternatively spliced to yield the A1 and A1b mRNAs, which encode proteins differing in their ability to modulate 5' splice site selection. Sequencing a genomic portion of the murine A1 gene revealed that the intron separating exon 7 and the alternative exon 7B is highly conserved between mouse and human. In vitro splicing assays indicate that a conserved element (CE1) from the central portion of the intron shifts selection toward the distal donor site when positioned in between the 5' splice sites of exon 7 and 7B. In vivo, the CE1 element promotes exon 7B skipping. A 17-nucleotide sequence within CE1 (CE1a) is sufficient to activate the distal 5' splice site. RNase T1 protection/immunoprecipitation assays indicate that hnRNP A1 binds to CE1a, which contains the sequence UAGAGU, a close match to the reported optimal A1 binding site, UAGGGU. Replacing CE1a by different oligonucleotides carrying the sequence UAGAGU or UAGGGU maintains the preference for the distal 5' splice site. In contrast, mutations in the AUGAGU sequence activate the proximal 5' splice site. In support of a direct role of the A1-CE1 interaction in 5'-splice-site selection, we observed that the amplitude of the shift correlates with the efficiency of A1 binding. Whereas addition of SR proteins abrogates the effect of CE1, the presence of CE1 does not modify U1 snRNP binding to competing 5' splice sites, as judged by oligonucleotide-targeted RNase H protection assays. Our results suggest that hnRNP A1 modulates splice site selection on its own pre-mRNA without changing the binding of U1 snRNP to competing 5' splice sites. PMID:9121425

  5. Site selection study for Sandia National Laboratories/New Mexico as an alternative site for the National Ignition Facility

    SciTech Connect

    Miller, D.; Wheeler, T.; McClellan, Y.

    1996-03-01

    The Department of Energy (DOE) proposes to construct and operate the National Ignition Facility (NIF) in support of the Stockpile Stewardship and Management (SSM) Programmatic Environmental impact Statement (PEIS). The National Environmental Policy Act requires the DOE to look at alternative sites for the NIF. The SSM PEIS will evaluate four alternative locations for the NIF. This study documents the process and results of a site selection study for a preferred site for the NIF at SNL/NM. The NIF research objectives are to provide the world`s most powerful laser systems to be used in ignition of fusion fuel and energy gain to perform high energy density and radiation effects experiments in support of the DOE`s national security, energy, and basic science research mission. The most immediate application of the NIF will be to provide nuclear-weapon-related physics data, since many phenomena occurring on the laboratory scale are similar to those that occur in weapons. The NIF may also provide an important capability for weapons effects simulation. The NIF is designed to achieve propagating fusion bum and modest energy gain for development as a source of civilian energy.

  6. Progress in site selection for China`s high-level radioactive waste repository

    SciTech Connect

    Xu, G.; Wang, J.; Jin, Y.; Chen, W.

    1995-12-31

    In 1985, the China National Nuclear Corporation (CNNC) worked out an R and D program called DG program for the deep geological disposal of high-level radioactive waste in China. The site selection process for China`s HLW repository has been carried out since then according to this program. Granite is considered as the candidate host rock for the repository. The general siting criteria are based on the principle that, under the effect of natural and human activities, the long term (100,000 years) safety of the repository can be reasonably obtained and the disposed radioactive waste can be avoided from entering the biosphere and harming human beings. During siting, two types of factors are considered: (1) social factors, including the nuclear industry distribution population, economic potential and environmental protection etc.; (2) natural factors, including geographic, meteorological and geological (crustal stability, host rocks, hydrogeology, engineering geology). The site selection process is divided into 4 stages: (1) nationwide screening, (2) regional screening; (3) district screening; and (4) site screening. During the first stage (1985--1986) the following were considered as potential regions: (1) southwest China, (2) Guangdong area, (3) Inner Mongolia, (4) east China and (5) northwest China. During the second stage (1986--1988), 21 districts were selected for further investigation. Since 1989 most efforts have been focused on the Beishan area, Gansu province, northwest China, which is considered as the most potential district for the repository.

  7. Transshipment site selection using the AHP and TOPSIS approaches under fuzzy environment

    SciTech Connect

    Onuet, Semih Soner, Selin

    2008-07-01

    Site selection is an important issue in waste management. Selection of the appropriate solid waste site requires consideration of multiple alternative solutions and evaluation criteria because of system complexity. Evaluation procedures involve several objectives, and it is often necessary to compromise among possibly conflicting tangible and intangible factors. For these reasons, multiple criteria decision-making (MCDM) has been found to be a useful approach to solve this kind of problem. Different MCDM models have been applied to solve this problem. But most of them are basically mathematical and ignore qualitative and often subjective considerations. It is easier for a decision-maker to describe a value for an alternative by using linguistic terms. In the fuzzy-based method, the rating of each alternative is described using linguistic terms, which can also be expressed as triangular fuzzy numbers. Furthermore, there have not been any studies focused on the site selection in waste management using both fuzzy TOPSIS (technique for order preference by similarity to ideal solution) and AHP (analytical hierarchy process) techniques. In this paper, a fuzzy TOPSIS based methodology is applied to solve the solid waste transshipment site selection problem in Istanbul, Turkey. The criteria weights are calculated by using the AHP.

  8. Assessment System for Junior High Schools in Taiwan to Select Environmental Education Facilities and Sites

    ERIC Educational Resources Information Center

    Ho, Shyue-Yung; Chen, Wen-Te; Hsu, Wei-Ling

    2017-01-01

    Environmental education is essential for people to pursue sustainable development. In Taiwan, environmental education is taught to students until they graduate from junior high school. This study was conducted to establish an assessment system for junior high schools to select appropriate environmental education facilities and sites. A mix of…

  9. 38 CFR 39.19 - General requirements for site selection and construction of veterans' cemeteries.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false General requirements for site selection and construction of veterans' cemeteries. 39.19 Section 39.19 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS (CONTINUED) AID TO STATES FOR ESTABLISHMENT, EXPANSION,...

  10. Decision precision or holistic heuristic?: Insights on on-site selection of student nurses and midwives.

    PubMed

    Macduff, Colin; Stephen, Audrey; Taylor, Ruth

    2016-01-01

    Concerns about quality of care delivery in the UK have led to more scrutiny of criteria and methods for the selection of student nurses. However few substantive research studies of on-site selection processes exist. This study elicited and interpreted perspectives on interviewing processes and related decision making involved in on-site selection of student nurses and midwives. Individual and focus group interviews were undertaken with 36 lecturers, 5 clinical staff and 72 students from seven Scottish universities. Enquiry focused primarily on interviewing of candidates on-site. Qualitative content analysis was used as a primary strategy, followed by in-depth thematic analysis. Students had very mixed experiences of interview processes. Staff typically took into account a range of candidate attributes that they valued in order to achieve holistic assessments. These included: interpersonal skills, team working, confidence, problem-solving, aptitude for caring, motivations, and commitment. Staff had mixed views of the validity and reliability of interview processes. A holistic heuristic for overall decision making predominated over belief in the precision of, and evidence base for, particular attribute measurement processes. While the development of measurement tools for particular attributes continues apace, tension between holism and precision is likely to persist within on-site selection procedures.

  11. 40 CFR 761.247 - Sample site selection for pipe segment removal.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Sample site selection for pipe segment removal. 761.247 Section 761.247 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT POLYCHLORINATED BIPHENYLS (PCBs) MANUFACTURING, PROCESSING, DISTRIBUTION...

  12. 40 CFR 761.250 - Sample site selection for pipeline section abandonment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., DISTRIBUTION IN COMMERCE, AND USE PROHIBITIONS Determining a PCB Concentration for Purposes of Abandonment or Disposal of Natural Gas Pipeline: Selecting Sample Sites, Collecting Surface Samples, and Analyzing... station downstream of the former gas flow, at a minimum, sample all ends of the abandoned pipe. (2) If...

  13. 40 CFR 761.247 - Sample site selection for pipe segment removal.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... porous surface. For purposes of this subpart, natural gas pipe with a thin porous corrosion preventive... COMMERCE, AND USE PROHIBITIONS Determining a PCB Concentration for Purposes of Abandonment or Disposal of Natural Gas Pipeline: Selecting Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB...

  14. 40 CFR 761.247 - Sample site selection for pipe segment removal.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... porous surface. For purposes of this subpart, natural gas pipe with a thin porous corrosion preventive... COMMERCE, AND USE PROHIBITIONS Determining a PCB Concentration for Purposes of Abandonment or Disposal of Natural Gas Pipeline: Selecting Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB...

  15. 40 CFR 761.250 - Sample site selection for pipeline section abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., DISTRIBUTION IN COMMERCE, AND USE PROHIBITIONS Determining a PCB Concentration for Purposes of Abandonment or Disposal of Natural Gas Pipeline: Selecting Sample Sites, Collecting Surface Samples, and Analyzing... station downstream of the former gas flow, at a minimum, sample all ends of the abandoned pipe. (2) If...

  16. Distributed Energy Resources On-Site Optimization for Commercial Buildings with Electric and Thermal Storage Technologies

    SciTech Connect

    Lacommare, Kristina S H; Stadler, Michael; Aki, Hirohisa; Firestone, Ryan; Lai, Judy; Marnay, Chris; Siddiqui, Afzal

    2008-05-15

    The addition of storage technologies such as flow batteries, conventional batteries, and heat storage can improve the economic as well as environmental attractiveness of on-site generation (e.g., PV, fuel cells, reciprocating engines or microturbines operating with or without CHP) and contribute to enhanced demand response. In order to examine the impact of storage technologies on demand response and carbon emissions, a microgrid's distributed energy resources (DER) adoption problem is formulated as a mixed-integer linear program that has the minimization of annual energy costs as its objective function. By implementing this approach in the General Algebraic Modeling System (GAMS), the problem is solved for a given test year at representative customer sites, such as schools and nursing homes, to obtain not only the level of technology investment, but also the optimal hourly operating schedules. This paper focuses on analysis of storage technologies in DER optimization on a building level, with example applications for commercial buildings. Preliminary analysis indicates that storage technologies respond effectively to time-varying electricity prices, i.e., by charging batteries during periods of low electricity prices and discharging them during peak hours. The results also indicate that storage technologies significantly alter the residual load profile, which can contribute to lower carbon emissions depending on the test site, its load profile, and its adopted DER technologies.

  17. Constructing Optimal Coarse-Grained Sites of Huge Biomolecules by Fluctuation Maximization.

    PubMed

    Li, Min; Zhang, John Zenghui; Xia, Fei

    2016-04-12

    Coarse-grained (CG) models are valuable tools for the study of functions of large biomolecules on large length and time scales. The definition of CG representations for huge biomolecules is always a formidable challenge. In this work, we propose a new method called fluctuation maximization coarse-graining (FM-CG) to construct the CG sites of biomolecules. The defined residual in FM-CG converges to a maximal value as the number of CG sites increases, allowing an optimal CG model to be rigorously defined on the basis of the maximum. More importantly, we developed a robust algorithm called stepwise local iterative optimization (SLIO) to accelerate the process of coarse-graining large biomolecules. By means of the efficient SLIO algorithm, the computational cost of coarse-graining large biomolecules is reduced to within the time scale of seconds, which is far lower than that of conventional simulated annealing. The coarse-graining of two huge systems, chaperonin GroEL and lengsin, indicates that our new methods can coarse-grain huge biomolecular systems with up to 10,000 residues within the time scale of minutes. The further parametrization of CG sites derived from FM-CG allows us to construct the corresponding CG models for studies of the functions of huge biomolecular systems.

  18. Rational optimization of tolC as a powerful dual selectable marker for genome engineering

    PubMed Central

    Gregg, Christopher J.; Lajoie, Marc J.; Napolitano, Michael G.; Mosberg, Joshua A.; Goodman, Daniel B.; Aach, John; Isaacs, Farren J.; Church, George M.

    2014-01-01

    Selection has been invaluable for genetic manipulation, although counter-selection has historically exhibited limited robustness and convenience. TolC, an outer membrane pore involved in transmembrane transport in E. coli, has been implemented as a selectable/counter-selectable marker, but counter-selection escape frequency using colicin E1 precludes using tolC for inefficient genetic manipulations and/or with large libraries. Here, we leveraged unbiased deep sequencing of 96 independent lineages exhibiting counter-selection escape to identify loss-of-function mutations, which offered mechanistic insight and guided strain engineering to reduce counter-selection escape frequency by ∼40-fold. We fundamentally improved the tolC counter-selection by supplementing a second agent, vancomycin, which reduces counter-selection escape by 425-fold, compared colicin E1 alone. Combining these improvements in a mismatch repair proficient strain reduced counter-selection escape frequency by 1.3E6-fold in total, making tolC counter-selection as effective as most selectable markers, and adding a valuable tool to the genome editing toolbox. These improvements permitted us to perform stable and continuous rounds of selection/counter-selection using tolC, enabling replacement of 10 alleles without requiring genotypic screening for the first time. Finally, we combined these advances to create an optimized E. coli strain for genome engineering that is ∼10-fold more efficient at achieving allelic diversity than previous best practices. PMID:24452804

  19. Mutation-selection models of coding sequence evolution with site-heterogeneous amino acid fitness profiles

    PubMed Central

    Rodrigue, Nicolas; Philippe, Hervé; Lartillot, Nicolas

    2010-01-01

    Modeling the interplay between mutation and selection at the molecular level is key to evolutionary studies. To this end, codon-based evolutionary models have been proposed as pertinent means of studying long-range evolutionary patterns and are widely used. However, these approaches have not yet consolidated results from amino acid level phylogenetic studies showing that selection acting on proteins displays strong site-specific effects, which translate into heterogeneous amino acid propensities across the columns of alignments; related codon-level studies have instead focused on either modeling a single selective context for all codon columns, or a separate selective context for each codon column, with the former strategy deemed too simplistic and the latter deemed overparameterized. Here, we integrate recent developments in nonparametric statistical approaches to propose a probabilistic model that accounts for the heterogeneity of amino acid fitness profiles across the coding positions of a gene. We apply the model to a dozen real protein-coding gene alignments and find it to produce biologically plausible inferences, for instance, as pertaining to site-specific amino acid constraints, as well as distributions of scaled selection coefficients. In their account of mutational features as well as the heterogeneous regimes of selection at the amino acid level, the modeling approaches studied here can form a backdrop for several extensions, accounting for other selective features, for variable population size, or for subtleties of mutational features, all with parameterizations couched within population-genetic theory. PMID:20176949

  20. A Genomic Study of the Bipolar Bud Site Selection Pattern in Saccharomyces cerevisiae

    PubMed Central

    Ni, Li; Snyder, Michael

    2001-01-01

    A genome-wide screen of 4168 homozygous diploid yeast deletion strains has been performed to identify nonessential genes that participate in the bipolar budding pattern. By examining bud scar patterns representing the sites of previous cell divisions, 127 mutants representing three different phenotypes were found: unipolar, axial-like, and random. From this screen, 11 functional classes of known genes were identified, including those involved in actin-cytoskeleton organization, general bud site selection, cell polarity, vesicular transport, cell wall synthesis, protein modification, transcription, nuclear function, translation, and other functions. Four characterized genes that were not known previously to participate in bud site selection were also found to be important for the haploid axial budding pattern. In addition to known genes, we found 22 novel genes (20 are designated BUD13-BUD32) important for bud site selection. Deletion of one resulted in unipolar budding exclusively from the proximal pole, suggesting that this gene plays an important role in diploid distal budding. Mutations in 20 other novel BUD genes produced a random budding phenotype and one produced an axial-like budding defect. Several of the novel Bud proteins were fused to green fluorescence protein; two proteins were found to localize to sites of polarized cell growth (i.e., the bud tip in small budded cells and the neck in cells undergoing cytokinesis), similar to that postulated for the bipolar signals and proteins that target cell division site tags to their proper location in the cell. Four others localized to the nucleus, suggesting that they play a role in gene expression. The bipolar distal marker Bud8 was localized in a number of mutants; many showed an altered Bud8-green fluorescence protein localization pattern. Through the genome-wide identification and analysis of different mutants involved in bipolar bud site selection, an integrated pathway for this process is presented in

  1. An Enhanced Grey Wolf Optimization Based Feature Selection Wrapped Kernel Extreme Learning Machine for Medical Diagnosis.

    PubMed

    Li, Qiang; Chen, Huiling; Huang, Hui; Zhao, Xuehua; Cai, ZhenNao; Tong, Changfei; Liu, Wenbin; Tian, Xin

    2017-01-01

    In this study, a new predictive framework is proposed by integrating an improved grey wolf optimization (IGWO) and kernel extreme learning machine (KELM), termed as IGWO-KELM, for medical diagnosis. The proposed IGWO feature selection approach is used for the purpose of finding the optimal feature subset for medical data. In the proposed approach, genetic algorithm (GA) was firstly adopted to generate the diversified initial positions, and then grey wolf optimization (GWO) was used to update the current positions of population in the discrete searching space, thus getting the optimal feature subset for the better classification purpose based on KELM. The proposed approach is compared against the original GA and GWO on the two common disease diagnosis problems in terms of a set of performance metrics, including classification accuracy, sensitivity, specificity, precision, G-mean, F-measure, and the size of selected features. The simulation results have proven the superiority of the proposed method over the other two competitive counterparts.

  2. GSMT Education: Teaching about Adaptive Optics and Site Selection Using Extremely Large Telescopes

    NASA Astrophysics Data System (ADS)

    Sparks, R. T.; Pompea, S. M.

    2010-08-01

    Giant Segmented Mirror Telescopes (GSMT) represents the next generation of extremely large telescopes (ELT). Currently there are three active ELT projects, all established as international partnerships to build telescopes of greater than 20 meters aperture. Two of these have major participation by U.S. institutions: the Giant Magellan Telescope and the Thirty Meter Telescope. The ESO-ELT is under development by the European Southern Observatory and other European institutions. We have developed educational activities to accompany the design phase of these projects. The current activities focus on challenges faced in the design and site selection of a large telescope. The first module is on site selection. This online module is based on the successful Astronomy Village program model. Students evaluate several potential sites to decide where to build the GSMT. They must consider factors such as weather, light pollution, seeing, logistics, and geography. The second project has developed adaptive optics teaching units suitable for high school.

  3. Laser site-selective spectroscopy of Eu3+ ions doped Y4Al2O9

    NASA Astrophysics Data System (ADS)

    Kaczkan, M.; Turczyński, S.; Pawlak, D. A.; Wencka, M.; Malinowski, M.

    2016-08-01

    Eu3+ doped Y4Al2O9 (YAM) crystals were prepared by the micro-pulling down method. Optical-absorption and laser-selective-excitation techniques along with the luminescence decays have been used to reveal that Eu3+ ions in YAM occupy three distinct sites, which were characterized and discussed. The Stark energy levels of Eu3+ at three different sites in YAM were assigned from selectively excited emission spectra at 10 K. The intensity ratio of forced electric dipole (5D0 → 7F2) and magnetic dipole (5D0 → 7F1) transitions was discussed in order to obtain information about the degree of asymmetry of the luminescent centers. These results were confirmed by the luminescence lifetime measurements. The temperature dependent photo-luminescence spectra indicated that there is no energy transfer between different sites in the 10-300 K range.

  4. Positive selection sites in tertiary structure of Leguminosae chalcone isomerase 1.

    PubMed

    Wang, R K; Zhan, S F; Zhao, T J; Zhou, X L; Wang, C E

    2015-03-20

    Isoflavonoids and the related synthesis enzyme, chalcone isomerase 1 (CHI1), are unique in the Leguminosae, with diverse biological functions. Among the Leguminosae, the soybean is an important oil, protein crop, and model plant. In this study, we aimed to detect the generation pattern of Leguminosae CHI1. Genome-wide sequence analysis of CHI in 3 Leguminosae and 3 other closely related model plants was performed; the expression levels of soybean chalcone isomerases were also analyzed. By comparing positively selected sites and their protein structures, we retrieved the evolution patterns for Leguminosae CHI1. A total of 28 CHI and 7 FAP3 (CHI4) genes were identified and separated into 4 clades: CHI1, CHI2, CHI3, and FAP3. Soybean genes belonging to the same chalcone isomerase subfamily had similar expression patterns. CHI1, the unique chalcone isomerase subfamily in Leguminosae, showed signs of significant positive selection as well as special expression characteristics, indicating an accelerated evolution throughout its divergence. Eight sites were identified as undergoing positive selection with high confidence. When mapped onto the tertiary structure of CHI1, these 8 sites were observed surrounding the enzyme substrate only; some of them connected to the catalytic core of CHI. Thus, we inferred that the generation of Leguminosae CHI1 is dependent on the positively selected amino acids surrounding its catalytic substrate. In other words, the evolution of CHI1 was driven by specific selection or processing conditions within the substrate.

  5. Optimization of meander line radiators for frequency selective surfaces by using genetic algorithm

    NASA Astrophysics Data System (ADS)

    Bucuci, Stefania C.; Dumitrascu, Ana; Danisor, Alin; Berescu, Serban; Tamas, Razvan D.

    2015-02-01

    In this paper we propose the use of frequency selective surfaces based on meander line radiators, as targets for monitoring slow displacements with synthetic aperture radars. The optimization of the radiators is performed by using genetic algorithms on only two parameters i.e., gain and size. As an example, we have optimized a single meander antenna, resonating in the X-band, at 9.65 GHz.

  6. Compression of biomedical signals with mother wavelet optimization and best-basis wavelet packet selection.

    PubMed

    Brechet, Laurent; Lucas, Marie-Françoise; Doncarli, Christian; Farina, Dario

    2007-12-01

    We propose a novel scheme for signal compression based on the discrete wavelet packet transform (DWPT) decompositon. The mother wavelet and the basis of wavelet packets were optimized and the wavelet coefficients were encoded with a modified version of the embedded zerotree algorithm. This signal dependant compression scheme was designed by a two-step process. The first (internal optimization) was the best basis selection that was performed for a given mother wavelet. For this purpose, three additive cost functions were applied and compared. The second (external optimization) was the selection of the mother wavelet based on the minimal distortion of the decoded signal given a fixed compression ratio. The mother wavelet was parameterized in the multiresolution analysis framework by the scaling filter, which is sufficient to define the entire decomposition in the orthogonal case. The method was tested on two sets of ten electromyographic (EMG) and ten electrocardiographic (ECG) signals that were compressed with compression ratios in the range of 50%-90%. For 90% compression ratio of EMG (ECG) signals, the percent residual difference after compression decreased from (mean +/- SD) 48.6 +/- 9.9% (21.5 +/- 8.4%) with discrete wavelet transform (DWT) using the wavelet leading to poorest performance to 28.4 +/- 3.0% (6.7 +/- 1.9%) with DWPT, with optimal basis selection and wavelet optimization. In conclusion, best basis selection and optimization of the mother wavelet through parameterization led to substantial improvement of performance in signal compression with respect to DWT and randon selection of the mother wavelet. The method provides an adaptive approach for optimal signal representation for compression and can thus be applied to any type of biomedical signal.

  7. Analyzing site selectivity in Rh2(esp)2-catalyzed intermolecular C-H amination reactions.

    PubMed

    Bess, Elizabeth N; DeLuca, Ryan J; Tindall, Daniel J; Oderinde, Martins S; Roizen, Jennifer L; Du Bois, J; Sigman, Matthew S

    2014-04-16

    Predicting site selectivity in C-H bond oxidation reactions involving heteroatom transfer is challenged by the small energetic differences between disparate bond types and the subtle interplay of steric and electronic effects that influence reactivity. Herein, the factors governing selective Rh2(esp)2-catalyzed C-H amination of isoamylbenzene derivatives are investigated, where modification to both the nitrogen source, a sulfamate ester, and substrate are shown to impact isomeric product ratios. Linear regression mathematical modeling is used to define a relationship that equates both IR stretching parameters and Hammett σ(+) values to the differential free energy of benzylic versus tertiary C-H amination. This model has informed the development of a novel sulfamate ester, which affords the highest benzylic-to-tertiary site selectivity (9.5:1) observed for this system.

  8. Computerized stratified random site-selection approaches for design of a ground-water-quality sampling network

    USGS Publications Warehouse

    Scott, J.C.

    1990-01-01

    Computer software was written to randomly select sites for a ground-water-quality sampling network. The software uses digital cartographic techniques and subroutines from a proprietary geographic information system. The report presents the approaches, computer software, and sample applications. It is often desirable to collect ground-water-quality samples from various areas in a study region that have different values of a spatial characteristic, such as land-use or hydrogeologic setting. A stratified network can be used for testing hypotheses about relations between spatial characteristics and water quality, or for calculating statistical descriptions of water-quality data that account for variations that correspond to the spatial characteristic. In the software described, a study region is subdivided into areal subsets that have a common spatial characteristic to stratify the population into several categories from which sampling sites are selected. Different numbers of sites may be selected from each category of areal subsets. A population of potential sampling sites may be defined by either specifying a fixed population of existing sites, or by preparing an equally spaced population of potential sites. In either case, each site is identified with a single category, depending on the value of the spatial characteristic of the areal subset in which the site is located. Sites are selected from one category at a time. One of two approaches may be used to select sites. Sites may be selected randomly, or the areal subsets in the category can be grouped into cells and sites selected randomly from each cell.

  9. Prolonged Integration Site Selection of a Lentiviral Vector in the Genome of Human Keratinocytes

    PubMed Central

    Qian, Wei; Wang, Yong; Li, Rui-fu; Zhou, Xin; Liu, Jing; Peng, Dai-zhi

    2017-01-01

    Background Lentiviral vectors have been successfully used for human skin cell gene transfer studies. Defining the selection of integration sites for retroviral vectors in the host genome is crucial in risk assessment analysis of gene therapy. However, genome-wide analyses of lentiviral integration sites in human keratinocytes, especially after prolonged growth, are poorly understood. Material/Methods In this study, 874 unique lentiviral vector integration sites in human HaCaT keratinocytes after long-term culture were identified and analyzed with the online tool GTSG-QuickMap and SPSS software. Results The data indicated that lentiviral vectors showed integration site preferences for genes and gene-rich regions. Conclusions This study will likely assist in determining the relative risks of the lentiviral vector system and in the design of a safe lentiviral vector system in the gene therapy of skin diseases. PMID:28255155

  10. Characteristics of candidate sites selected for onsite fuel cell power plant testing

    NASA Astrophysics Data System (ADS)

    Racine, W. C.; Ferraro, V. D.; Woods, R. R.

    A portion of the Onsite Fuel Cell Program involves field testing forty-nine, 40-kW onsite fuel cell power plants. This paper describes the energy characteristics of 82 different sites that have been selected as potential field test locations. The 82 sites include multi-family residential, commercial and light industrial buildings that represent 26 market segments throughout the United States and Japan. Each one of the 82 sites has been instrumented with a standard data acquisition system to obtain hourly thermal and electrical energy consumption data. This energy data will help determine each site's compatibility with a 40-kW fuel cell power plant, and will provide an extensive data base which may be useful in other energy studies.

  11. Determining Optimal Location and Numbers of Sample Transects for Characterization of UXO Sites

    SciTech Connect

    BILISOLY, ROGER L.; MCKENNA, SEAN A.

    2003-01-01

    Previous work on sample design has been focused on constructing designs for samples taken at point locations. Significantly less work has been done on sample design for data collected along transects. A review of approaches to point and transect sampling design shows that transects can be considered as a sequential set of point samples. Any two sampling designs can be compared through using each one to predict the value of the quantity being measured on a fixed reference grid. The quality of a design is quantified in two ways: computing either the sum or the product of the eigenvalues of the variance matrix of the prediction error. An important aspect of this analysis is that the reduction of the mean prediction error variance (MPEV) can be calculated for any proposed sample design, including one with straight and/or meandering transects, prior to taking those samples. This reduction in variance can be used as a ''stopping rule'' to determine when enough transect sampling has been completed on the site. Two approaches for the optimization of the transect locations are presented. The first minimizes the sum of the eigenvalues of the predictive error, and the second minimizes the product of these eigenvalues. Simulated annealing is used to identify transect locations that meet either of these objectives. This algorithm is applied to a hypothetical site to determine the optimal locations of two iterations of meandering transects given a previously existing straight transect. The MPEV calculation is also used on both a hypothetical site and on data collected at the Isleta Pueblo to evaluate its potential as a stopping rule. Results show that three or four rounds of systematic sampling with straight parallel transects covering 30 percent or less of the site, can reduce the initial MPEV by as much as 90 percent. The amount of reduction in MPEV can be used as a stopping rule, but the relationship between MPEV and the results of excavation versus no

  12. Diet and density dependent competition affect larval performance and oviposition site selection in the mosquito species Aedes albopictus (Diptera: Culicidae)

    PubMed Central

    2012-01-01

    Background Oviposition-site choice is an essential component of the life history of all mosquito species. According to the oviposition-preference offspring-performance (P-P) hypothesis, if optimizing offspring performance and fitness ensures high overall reproductive fitness for a given species, the female should accurately assess details of the heterogeneous environment and lay her eggs preferentially in sites with conditions more suitable to offspring. Methods We empirically tested the P-P hypothesis using the mosquito species Aedes albopictus by artificially manipulating two habitat conditions: diet (measured as mg of food added to a container) and conspecific density (CD; number of pre-existing larvae of the same species). Immature development (larval mortality, development time to pupation and time to emergence) and fitness (measured as wing length) were monitored from first instar through adult emergence using a factorial experimental design over two ascending gradients of diet (2.0, 3.6, 7.2 and 20 mg food/300 ml water) and CD (0, 20, 40 and 80 larvae/300 ml water). Treatments that exerted the most contrasting values of larval performance were recreated in a second experiment consisting of single-female oviposition site selection assay. Results Development time decreased as food concentration increased, except from 7.2 mg to 20.0 mg (Two-Way CR ANOVA Post-Hoc test, P > 0.1). Development time decreased also as conspecific density increased from zero to 80 larvae (Two-Way CR ANOVA Post-Hoc test, P < 0.5). Combined, these results support the role of density-dependent competition for resources as a limiting factor for mosquito larval performance. Oviposition assays indicated that female mosquitoes select for larval habitats with conspecifics and that larval density was more important than diet in driving selection for oviposition sites. Conclusions This study supports predictions of the P-P hypothesis and provides a mechanistic understanding of the

  13. Shorebird roost-site selection at two temporal scales: Is human disturbance a factor?

    USGS Publications Warehouse

    Peters, K.A.; Otis, D.L.

    2007-01-01

    1. Roost-site selection in shorebirds is governed by ambient factors, including environmental conditions and human disturbance. Determination of the extent to which these factors affect roost use and the associated implications for shorebird habitat protection is important for conservation strategies and informed management of human recreational use of these habitats. Shorebird conservation as a whole is a high priority world-wide because a large proportion of shorebird species is in decline. However, little is understood about the consistency of roost use by different species, what conditions affect species-specific roost-site selection, and at what spatial and temporal scales conditions influence selection. 2. We studied high-tide roost-site selection by eight species of non-breeding shorebirds on a critically important stopover and wintering refuge. We calculated spatial and temporal variability in roost use for each species based on counts and consistency of incidence. We then examined roost-site selection in relation to structural, environmental and human disturbance factors, and how this varied across spatial and temporal scales. 3. Most roosts were used less than 50% of the time, although larger roosts were used more consistently. This varied among species, with red knot Calidris canutus tending to concentrate at a few roosts and American oystercatcher Haematopus palliatus, dowitcher Limnodromus griseus and Limnodromus scolopaceus and ruddy turnstone Arenaria interpres more diffusely distributed among roosts. 4. At an annual scale, the principal factors affecting shorebird presence at roosts were roost length (size), local region, substrate and aspect. The extent and direction of these effects varied among species. Among years, red knots avoided roosts that had high average boat activity within 1000 m, but disturbance did not appear to be a factor for other species. 5. Daily roost use was influenced primarily by wind speed and the ability of roosts to

  14. Selective Optimization

    DTIC Science & Technology

    2015-07-06

    thanks Dave Goldsman and Alexander Shapiro for valuable discussions. References [1] Shabbir Ahmed and Alper Atamtürk. Maximizing a class of...Progressive hedging-based metaheuristics for stochastic network design. Networks, 58(2):114–124, 2011. [7] Edgar Gabriel, Graham E. Fagg, George...J. Daniel, Richard L. Graham , and Timothy S. Woodall. Open MPI: Goals, concept, and design of a next generation MPI implementation. In Proceedings

  15. DNA abasic site-directed formation of fluorescent silver nanoclusters for selective nucleobase recognition

    NASA Astrophysics Data System (ADS)

    Ma, Kun; Cui, Qinghua; Liu, Guiying; Wu, Fei; Xu, Shujuan; Shao, Yong

    2011-07-01

    DNA single-nucleotide polymorphism (SNP) detection has attracted much attention due to mutation related diseases. Various methods for SNP detection have been proposed and many are already in use. Here, we find that the abasic site (AP site) in the DNA duplex can be developed as a capping scaffold for the generation of fluorescent silver nanoclusters (Ag NCs). As a proof of concept, the DNA sequences from fragments near codon 177 of cancer supression gene p53 were used as a model for SNP detection by in situ formed Ag NCs. The formation of fluorescent Ag NCs in the AP site-containing DNA duplex is highly selective for cytosine facing the AP site and guanines flanking the site and can be employed in situ as readout for SNP detection. The fluorescent signal-on sensing for SNP based on this inorganic fluorophore is substantially advantageous over the previously reported signal-off responses using low-molecular-weight organic ligands. The strong dependence of fluorescent Ag NC formation on the sequences surrounding the AP site was successfully used to identify mutations in codon 177 of cancer supression gene p53. We anticipate that this approach will be employed to develop a practical SNP detection method by locating an AP site toward the midway cytosine in a target strand containing more than three consecutive cytosines.

  16. Selective waste collection optimization in Romania and its impact to urban climate

    NASA Astrophysics Data System (ADS)

    Mihai, Šercǎianu; Iacoboaea, Cristina; Petrescu, Florian; Aldea, Mihaela; Luca, Oana; Gaman, Florian; Parlow, Eberhard

    2016-08-01

    According to European Directives, transposed in national legislation, the Member States should organize separate collection systems at least for paper, metal, plastic, and glass until 2015. In Romania, since 2011 only 12% of municipal collected waste was recovered, the rest being stored in landfills, although storage is considered the last option in the waste hierarchy. At the same time there was selectively collected only 4% of the municipal waste. Surveys have shown that the Romanian people do not have selective collection bins close to their residencies. The article aims to analyze the current situation in Romania in the field of waste collection and management and to make a proposal for selective collection containers layout, using geographic information systems tools, for a case study in Romania. Route optimization is used based on remote sensing technologies and network analyst protocols. Optimizing selective collection system the greenhouse gases, particles and dust emissions can be reduced.

  17. Selective targeting of the conserved active site cysteine of Mycobacterium tuberculosis methionine aminopeptidase with electrophilic reagents.

    PubMed

    Reddi, Ravikumar; Arya, Tarun; Kishor, Chandan; Gumpena, Rajesh; Ganji, Roopa J; Bhukya, Supriya; Addlagatta, Anthony

    2014-09-01

    Methionine aminopeptidases (MetAPs) cleave initiator methionine from ~ 70% of the newly synthesized proteins in every living cell, and specific inhibition or knockdown of this function is detrimental. MetAPs are metalloenzymes, and are broadly classified into two subtypes, type I and type II. Bacteria contain only type I MetAPs, and the active site of these enzymes contains a conserved cysteine. By contrast, in type II enzymes the analogous position is occupied by a conserved glycine. Here, we report the reactivity of the active site cysteine in a type I MetAP, MetAP1c, of Mycobacterium tuberculosis (MtMetAP1c) towards highly selective cysteine-specific reagents. The authenticity of selective modification of Cys105 of MtMetAP1c was established by using site-directed mutagenesis and crystal structure determination of covalent and noncovalent complexes. On the basis of these observations, we propose that metal ions in the active site assist in the covalent modification of Cys105 by orienting the reagents appropriately for a successful reaction. These studies establish, for the first time, that the conserved cysteine of type I MetAPs can be targeted for selective inhibition, and we believe that this chemistry can be exploited for further drug discovery efforts regarding microbial MetAPs.

  18. Chromosome segregation impacts on cell growth and division site selection in Corynebacterium glutamicum.

    PubMed

    Donovan, Catriona; Schauss, Astrid; Krämer, Reinhard; Bramkamp, Marc

    2013-01-01

    Spatial and temporal regulation of bacterial cell division is imperative for the production of viable offspring. In many rod-shaped bacteria, regulatory systems such as the Min system and nucleoid occlusion ensure the high fidelity of midcell divisome positioning. However, regulation of division site selection in bacteria lacking recognizable Min and nucleoid occlusion remains less well understood. Here, we describe one such rod-shaped organism, Corynebacterium glutamicum, which does not always place the division septum precisely at midcell. Here we now show at single cell level that cell growth and division site selection are spatially and temporally regulated by chromosome segregation. Mutants defective in chromosome segregation have more variable cell growth and aberrant placement of the division site. In these mutants, division septa constrict over and often guillotine the nucleoid, leading to nonviable, DNA-free cells. Our results suggest that chromosome segregation or some nucleoid associated factor influences growth and division site selection in C. glutamicum. Understanding growth and regulation of C. glutamicum cells will also be of importance to develop strains for industrial production of biomolecules, such as amino acids.

  19. Chromosome Segregation Impacts on Cell Growth and Division Site Selection in Corynebacterium glutamicum

    PubMed Central

    Donovan, Catriona; Schauss, Astrid; Krämer, Reinhard; Bramkamp, Marc

    2013-01-01

    Spatial and temporal regulation of bacterial cell division is imperative for the production of viable offspring. In many rod-shaped bacteria, regulatory systems such as the Min system and nucleoid occlusion ensure the high fidelity of midcell divisome positioning. However, regulation of division site selection in bacteria lacking recognizable Min and nucleoid occlusion remains less well understood. Here, we describe one such rod-shaped organism, Corynebacterium glutamicum, which does not always place the division septum precisely at midcell. Here we now show at single cell level that cell growth and division site selection are spatially and temporally regulated by chromosome segregation. Mutants defective in chromosome segregation have more variable cell growth and aberrant placement of the division site. In these mutants, division septa constrict over and often guillotine the nucleoid, leading to nonviable, DNA-free cells. Our results suggest that chromosome segregation or some nucleoid associated factor influences growth and division site selection in C. glutamicum. Understanding growth and regulation of C. glutamicum cells will also be of importance to develop strains for industrial production of biomolecules, such as amino acids. PMID:23405112

  20. Use and Selection of Sleeping Sites by Proboscis Monkeys, Nasalislarvatus, along the Kinabatangan River, Sabah, Malaysia.

    PubMed

    Thiry, Valentine; Stark, Danica J; Goossens, Benoît; Slachmuylder, Jean-Louis; Vercauteren Drubbel, Régine; Vercauteren, Martine

    2016-01-01

    The choice of a sleeping site is crucial for primates and may influence their survival. In this study, we investigated several tree characteristics influencing the sleeping site selection by proboscis monkeys (Nasalis larvatus) along Kinabatangan River, in Sabah, Malaysia. We identified 81 sleeping trees used by one-male and all-male social groups from November 2011 to January 2012. We recorded 15 variables for each tree. Within sleeping sites, sleeping trees were taller, had a larger trunk, with larger and higher first branches than surrounding trees. The crown contained more mature leaves, ripe and unripe fruits but had vines less often than surrounding trees. In addition, in this study, we also focused on a larger scale, considering sleeping and non-sleeping sites. Multivariate analyses highlighted a combination of 6 variables that revealed the significance of sleeping trees as well as surrounding trees in the selection process. During our boat surveys, we observed that adult females and young individuals stayed higher in the canopy than adult males. This pattern may be driven by their increased vulnerability to predation. Finally, we suggest that the selection of particular sleeping tree features (i.e. tall, high first branch) by proboscis monkeys is mostly influenced by antipredation strategies.

  1. Selection of area and specific site for drilling a horizontal well in Calhoun County, West Virginia

    SciTech Connect

    Reeves, T.K.; Overbey, W.K. Jr.; Salamy, S.P.; Locke, C.D.

    1992-03-01

    This report discusses the data collection and analysis procedures used to establish criteria for geologic and engineering studies conducted by BDM to select a general area for more detailed study and a specific site for the drilling of a cooperative well with an industry partner, the Consolidated Natural Gas Development Company (CNGD). The results of detailed geologic studies are presented for two areas in Calhoun County, West Virginia, and one area along the Logan-Boone County line in West Virginia. The effects of Appalachian Basin tectonics and the Rome Trough Rift system were identified on seismic lines made available by (CNGD). These helped to identify and define the trapping mechanisms which had been effective in each area. Engineering analyses of past production histories provided data to support selection of target areas and then to select a specific site that met the project requirements for production, reservoir pressure, and risk. A final site was selected in Lee District at the southwestern margin of the Sand Ridge gas field based on the combination of a geologic trapping mechanism and reservoir pressures which were projected as 580 psi with a stress ratio of 0.53.

  2. Decision Making on Regional Landfill Site Selection in Hormozgan Province Using Smce

    NASA Astrophysics Data System (ADS)

    Majedi, A. S.; Kamali, B. M.; Maghsoudi, R.

    2015-12-01

    Landfill site selection and suitable conditions to bury hazardous wastes are among the most critical issues in modern societies. Taking several factors and limitations into account along with true decision making requires application of different decision techniques. To this end, current paper aims to make decisions about regional landfill site selection in Hormozgan province and utilizes SMCE technique combined with qualitative and quantitative criteria to select the final alternatives. To this respect, we first will describe the existing environmental situation in our study area and set the goals of our study in the framework of SMCE and will analyze the effective factors in regional landfill site selection. Then, methodological procedure of research was conducted using Delphi approach and questionnaires (in order to determine research validity, Chronbach Alpha (0.94) method was used). Spatial multi-criteria analysis model was designed in the form of criteria tree in SMCE using IL WIS software. Prioritization of respective spatial alternatives included: Bandar Abbas city with total 4 spatial alternatives (one zone with 1st priority, one zone with 3rd priority and two zones with 4thpriority) was considered the first priority, Bastak city with total 3 spatial alternatives (one zone with 2nd priority, one zone with 3rdpriorit and one zone with 4th priority) was the second priority and Bandar Abbas, Minab, Jask and Haji Abad cities were considered as the third priority.

  3. A framework for implementing biodiversity offsets: selecting sites and determining scale

    USGS Publications Warehouse

    Kiesecker, Joseph M.; Copeland, Holly; Pocewicz, Amy; Nibbelink, Nate; McKenney, Bruce; Dahlke, John; Holloran, Matthew J.; Stroud, Dan

    2009-01-01

    Biodiversity offsets provide a mechanism for maintaining or enhancing environmental values in situations where development is sought despite detrimental environmental impacts. They seek to ensure that unavoidable negative environmental impacts of development are balanced by environmental gains, with the overall aim of achieving a net neutral or positive outcome. Once the decision has been made to offset, multiple issues arise regarding how to do so in practice. A key concern is site selection. In light of the general aim to locate offsets close to the affected sites to ensure that benefits accrue in the same area, what is the appropriate spatial scale for identifying potential offset sites (e.g., local, ecoregional)? We use the Marxan site-selection algorithm to address conceptual and methodological challenges associated with identifying a set of potential offset sites and determining an appropriate spatial scale for them. To demonstrate this process, we examined the design of offsets for impacts from development on the Jonah natural gas field in Wyoming.

  4. Glanzmann thrombasthenia. Cooperation between sequence variants in cis during splice site selection.

    PubMed Central

    Jin, Y; Dietz, H C; Montgomery, R A; Bell, W R; McIntosh, I; Coller, B; Bray, P F

    1996-01-01

    Glanzmann thrombasthenia (GT), an autosomal recessive bleeding disorder, results from abnormalities in the platelet fibrinogen receptor, GP(IIb)-IIIa (integrin alpha(IIb)beta3). A patient with GT was identified as homozygous for a G-->A mutation 6 bp upstream of the GP(IIIa) exon 9 splice donor site. Patient platelet GP(IIIa) transcripts lacked exon 9 despite normal DNA sequence in all of the cis-acting sequences known to regulate splice site selection. In vitro analysis of transcripts generated from mini-gene constructs demonstrated that exon skipping occurred only when the G-->A mutation was cis to a polymorphism 116 bp upstream, providing precedence that two sequence variations in the same exon which do not alter consensus splice sites and do not generate missense or nonsense mutations, can affect splice site selection. The mutant transcript resulted from utilization of a cryptic splice acceptor site and returned the open reading frame. These data support the hypothesis that pre-mRNA secondary structure and allelic sequence variants can influence splicing and provide new insight into the regulated control of RNA processing. In addition, haplotype analysis suggested that the patient has two identical copies of chromosome 17. Markers studied on three other chromosomes suggested this finding was not due to consanguinity. The restricted phenotype in this patient may provide information regarding the expression of potentially imprinted genes on chromosome 17. PMID:8878424

  5. A comprehensive study on landfill site selection for Kolkata City, India.

    PubMed

    Paul, Koushik; Dutta, Amit; Krishna, A P

    2014-07-01

    Kolkata is one of the four major metropolitan cities in India and the capital city of the state of West Bengal. With an area of 187.33 km2 and a population of about 10 million (including a floating population of about 6 million), the city generates about 3500 Metric Ton (MT) of solid waste per day. Currently, Kolkata Municipal Corporation (KMC) disposes its waste at Dhapa (21.47 ha), where the disposal rate exceeds 3000 MT/day, and at Garden Reach (3.52 ha), where the disposal rate is 100 MT/day. Considering the exhaustion of Dhapa land space, city planners are urgently searching for an alternate disposal ground. National Environmental Engineering Research Institute (NEERI), under the sponsorship of Central Pollution Control Board (CPCB), has brought out literature developing the site selection criteria for municipal solid waste disposal ground to suit Indian conditions. The developed criteria encompass environmental conditions, accessibility, geological and hydrogeological conditions, and ecological and societal effects. This paper attempts to locate the most suitable site for disposal of KMC area solid waste using the multicriterion decision analysis as stipulated in CPCB 2003 guidelines and the overlay analysis of geographic information system (GIS). Implications: The paper is based on landfill site selection for dumping of solid waste generated within Kolkata Municipal Corporation (KMC) area. The methodology uses GIS/remote sensing, Site Sensitivity Index (an offshoot of pairwise comparison technique developed in CPCB 2003 guidelines, Government of India), and the Delphi technique. Dhapa landfill site, where solid waste of KMC area is currently being disposed, is exhausted; the authors of this article thus found it relevant to carry out a research on the selection of an alternative landfill site. The study undertaken was comprehensive, yet presented in a lucid way so that policymakers will find easy to comprehend.

  6. Seeing the Forest through the Trees: Considering Roost-Site Selection at Multiple Spatial Scales

    PubMed Central

    Jachowski, David S.; Rota, Christopher T.; Dobony, Christopher A.; Ford, W. Mark; Edwards, John W.

    2016-01-01

    Conservation of bat species is one of the most daunting wildlife conservation challenges in North America, requiring detailed knowledge about their ecology to guide conservation efforts. Outside of the hibernating season, bats in temperate forest environments spend their diurnal time in day-roosts. In addition to simple shelter, summer roost availability is as critical as maternity sites and maintaining social group contact. To date, a major focus of bat conservation has concentrated on conserving individual roost sites, with comparatively less focus on the role that broader habitat conditions contribute towards roost-site selection. We evaluated roost-site selection by a northern population of federally-endangered Indiana bats (Myotis sodalis) at Fort Drum Military Installation in New York, USA at three different spatial scales: landscape, forest stand, and individual tree level. During 2007–2011, we radiotracked 33 Indiana bats (10 males, 23 females) and located 348 roosting events in 116 unique roost trees. At the landscape scale, bat roost-site selection was positively associated with northern mixed forest, increased slope, and greater distance from human development. At the stand scale, we observed subtle differences in roost site selection based on sex and season, but roost selection was generally positively associated with larger stands with a higher basal area, larger tree diameter, and a greater sugar maple (Acer saccharum) component. We observed no distinct trends of roosts being near high-quality foraging areas of water and forest edges. At the tree scale, roosts were typically in American elm (Ulmus americana) or sugar maple of large diameter (>30 cm) of moderate decay with loose bark. Collectively, our results highlight the importance of considering day roost needs simultaneously across multiple spatial scales. Size and decay class of individual roosts are key ecological attributes for the Indiana bat, however, larger-scale stand structural

  7. Selecting and Certifying a Landing Site for Moonrise in South Pole-Aitken Basin

    NASA Technical Reports Server (NTRS)

    Jolliff, B.; Watkins, R.; Petro, N.; Moriarty, D.; Lawrence, S.; Head, J.; Pieters, C.; Hagerty, J.; Fergason, R.; Hare, T.; Gaddis, L.; Hayne, P.

    2017-01-01

    MoonRise is a New Frontiers mission concept to land in the South Pole-Aitken (SPA) basin, collect samples, and return the samples to Earth for detailed mineral, chemical, petrologic, geochronologic, and physical properties analyses to address science questions relevant to the early evolution of the Solar System and the Moon. Science associated with this mission concept is described elsewhere; here we discuss selection of sites within SPA to address science objectives using recent scientific studies (orbital spectroscopy, gravity, topography), and the use of new data (LRO) to certify safe landing sites for a robotic sample return mission such as MoonRise.

  8. Site-Selective Disulfide Modification of Proteins: Expanding Diversity beyond the Proteome.

    PubMed

    Kuan, Seah Ling; Wang, Tao; Weil, Tanja

    2016-11-21

    The synthetic transformation of polypeptides with molecular accuracy holds great promise for providing functional and structural diversity beyond the proteome. Consequently, the last decade has seen an exponential growth of site-directed chemistry to install additional features into peptides and proteins even inside living cells. The disulfide rebridging strategy has emerged as a powerful tool for site-selective modifications since most proteins contain disulfide bonds. In this Review, we present the chemical design, advantages and limitations of the disulfide rebridging reagents, while summarizing their relevance for synthetic customization of functional protein bioconjugates, as well as the resultant impact and advancement for biomedical applications.

  9. Catalyst recognition of cis-1,2-diols enables site-selective functionalization of complex molecules

    NASA Astrophysics Data System (ADS)

    Sun, Xixi; Lee, Hyelee; Lee, Sunggi; Tan, Kian L.

    2013-09-01

    Carbohydrates and natural products serve essential roles in nature, and also provide core scaffolds for pharmaceutical agents and vaccines. However, the inherent complexity of these molecules imposes significant synthetic hurdles for their selective functionalization and derivatization. Nature has, in part, addressed these issues by employing enzymes that are able to orient and activate substrates within a chiral pocket, which increases dramatically both the rate and selectivity of organic transformations. In this article we show that similar proximity effects can be utilized in the context of synthetic catalysts to achieve general and predictable site-selective functionalization of complex molecules. Unlike enzymes, our catalysts apply a single reversible covalent bond to recognize and bind to specific functional group displays within substrates. By combining this unique binding selectivity and asymmetric catalysis, we are able to modify the less reactive axial positions within monosaccharides and natural products.

  10. Optimal band selection for high dimensional remote sensing data using genetic algorithm

    NASA Astrophysics Data System (ADS)

    Zhang, Xianfeng; Sun, Quan; Li, Jonathan

    2009-06-01

    A 'fused' method may not be suitable for reducing the dimensionality of data and a band/feature selection method needs to be used for selecting an optimal subset of original data bands. This study examined the efficiency of GA in band selection for remote sensing classification. A GA-based algorithm for band selection was designed deliberately in which a Bhattacharyya distance index that indicates separability between classes of interest is used as fitness function. A binary string chromosome is designed in which each gene location has a value of 1 representing a feature being included or 0 representing a band being not included. The algorithm was implemented in MATLAB programming environment, and a band selection task for lithologic classification in the Chocolate Mountain area (California) was used to test the proposed algorithm. The proposed feature selection algorithm can be useful in multi-source remote sensing data preprocessing, especially in hyperspectral dimensionality reduction.

  11. Parameter Selection and Performance Comparison of Particle Swarm Optimization in Sensor Networks Localization

    PubMed Central

    Cui, Huanqing; Shu, Minglei; Song, Min; Wang, Yinglong

    2017-01-01

    Localization is a key technology in wireless sensor networks. Faced with the challenges of the sensors’ memory, computational constraints, and limited energy, particle swarm optimization has been widely applied in the localization of wireless sensor networks, demonstrating better performance than other optimization methods. In particle swarm optimization-based localization algorithms, the variants and parameters should be chosen elaborately to achieve the best performance. However, there is a lack of guidance on how to choose these variants and parameters. Further, there is no comprehensive performance comparison among particle swarm optimization algorithms. The main contribution of this paper is three-fold. First, it surveys the popular particle swarm optimization variants and particle swarm optimization-based localization algorithms for wireless sensor networks. Secondly, it presents parameter selection of nine particle swarm optimization variants and six types of swarm topologies by extensive simulations. Thirdly, it comprehensively compares the performance of these algorithms. The results show that the particle swarm optimization with constriction coefficient using ring topology outperforms other variants and swarm topologies, and it performs better than the second-order cone programming algorithm. PMID:28257060

  12. Ant Colony Optimization Based Feature Selection Method for QEEG Data Classification

    PubMed Central

    Ozekes, Serhat; Gultekin, Selahattin; Tarhan, Nevzat

    2014-01-01

    Objective Many applications such as biomedical signals require selecting a subset of the input features in order to represent the whole set of features. A feature selection algorithm has recently been proposed as a new approach for feature subset selection. Methods Feature selection process using ant colony optimization (ACO) for 6 channel pre-treatment electroencephalogram (EEG) data from theta and delta frequency bands is combined with back propagation neural network (BPNN) classification method for 147 major depressive disorder (MDD) subjects. Results BPNN classified R subjects with 91.83% overall accuracy and 95.55% subjects detection sensitivity. Area under ROC curve (AUC) value after feature selection increased from 0.8531 to 0.911. The features selected by the optimization algorithm were Fp1, Fp2, F7, F8, F3 for theta frequency band and eliminated 7 features from 12 to 5 feature subset. Conclusion ACO feature selection algorithm improves the classification accuracy of BPNN. Using other feature selection algorithms or classifiers to compare the performance for each approach is important to underline the validity and versatility of the designed combination. PMID:25110496

  13. Multi-Objective Particle Swarm Optimization Approach for Cost-Based Feature Selection in Classification.

    PubMed

    Zhang, Yong; Gong, Dun-Wei; Cheng, Jian

    2017-01-01

    Feature selection is an important data-preprocessing technique in classification problems such as bioinformatics and signal processing. Generally, there are some situations where a user is interested in not only maximizing the classification performance but also minimizing the cost that may be associated with features. This kind of problem is called cost-based feature selection. However, most existing feature selection approaches treat this task as a single-objective optimization problem. This paper presents the first study of multi-objective particle swarm optimization (PSO) for cost-based feature selection problems. The task of this paper is to generate a Pareto front of nondominated solutions, that is, feature subsets, to meet different requirements of decision-makers in real-world applications. In order to enhance the search capability of the proposed algorithm, a probability-based encoding technology and an effective hybrid operator, together with the ideas of the crowding distance, the external archive, and the Pareto domination relationship, are applied to PSO. The proposed PSO-based multi-objective feature selection algorithm is compared with several multi-objective feature selection algorithms on five benchmark datasets. Experimental results show that the proposed algorithm can automatically evolve a set of nondominated solutions, and it is a highly competitive feature selection method for solving cost-based feature selection problems.

  14. Spawning site selection and contingent behavior in Common Snook, Centropomus undecimalis.

    PubMed

    Lowerre-Barbieri, Susan; Villegas-Ríos, David; Walters, Sarah; Bickford, Joel; Cooper, Wade; Muller, Robert; Trotter, Alexis

    2014-01-01

    Reproductive behavior affects spatial population structure and our ability to manage for sustainability in marine and diadromous fishes. In this study, we used fishery independent capture-based sampling to evaluate where Common Snook occurred in Tampa Bay and if it changed with spawning season, and passive acoustic telemetry to assess fine scale behavior at an inlet spawning site (2007-2009). Snook concentrated in three areas during the spawning season only one of which fell within the expected spawning habitat. Although in lower numbers, they remained in these areas throughout the winter months. Acoustically-tagged snook (n = 31) showed two seasonal patterns at the spawning site: Most fish occurred during the spawning season but several fish displayed more extended residency, supporting the capture-based findings that Common Snook exhibit facultative catadromy. Spawning site selection for iteroparous, multiple-batch spawning fishes occurs at the lifetime, annual, or intra-annual temporal scales. In this study we show colonization of a new spawning site, indicating that lifetime spawning site fidelity of Common Snook is not fixed at this fine spatial scale. However, individuals did exhibit annual and intra-seasonal spawning site fidelity to this new site over the three years studied. The number of fish at the spawning site increased in June and July (peak spawning months) and on new and full lunar phases indicating within population variability in spawning and movement patterns. Intra-seasonal patterns of detection also differed significantly with sex. Common Snook exhibited divergent migration tactics and habitat use at the annual and estuarine scales, with contingents using different overwintering habitat. Migration tactics also varied at the spawning site at the intra-seasonal scale and with sex. These results have important implications for understanding how reproductive behavior affects spatio-temporal patterns of fish abundance and their resilience to

  15. Quantum-behaved particle swarm optimization: analysis of individual particle behavior and parameter selection.

    PubMed

    Sun, Jun; Fang, Wei; Wu, Xiaojun; Palade, Vasile; Xu, Wenbo

    2012-01-01

    Quantum-behaved particle swarm optimization (QPSO), motivated by concepts from quantum mechanics and particle swarm optimization (PSO), is a probabilistic optimization algorithm belonging to the bare-bones PSO family. Although it has been shown to perform well in finding the optimal solutions for many optimization problems, there has so far been little analysis on how it works in detail. This paper presents a comprehensive analysis of the QPSO algorithm. In the theoretical analysis, we analyze the behavior of a single particle in QPSO in terms of probability measure. Since the particle's behavior is influenced by the contraction-expansion (CE) coefficient, which is the most important parameter of the algorithm, the goal of the theoretical analysis is to find out the upper bound of the CE coefficient, within which the value of the CE coefficient selected can guarantee the convergence or boundedness of the particle's position. In the experimental analysis, the theoretical results are first validated by stochastic simulations for the particle's behavior. Then, based on the derived upper bound of the CE coefficient, we perform empirical studies on a suite of well-known benchmark functions to show how to control and select the value of the CE coefficient, in order to obtain generally good algorithmic performance in real world applications. Finally, a further performance comparison between QPSO and other variants of PSO on the benchmarks is made to show the efficiency of the QPSO algorithm with the proposed parameter control and selection methods.

  16. Adaptive feature selection using v-shaped binary particle swarm optimization

    PubMed Central

    Dong, Hongbin; Zhou, Xiurong

    2017-01-01

    Feature selection is an important preprocessing method in machine learning and data mining. This process can be used not only to reduce the amount of data to be analyzed but also to build models with stronger interpretability based on fewer features. Traditional feature selection methods evaluate the dependency and redundancy of features separately, which leads to a lack of measurement of their combined effect. Moreover, a greedy search considers only the optimization of the current round and thus cannot be a global search. To evaluate the combined effect of different subsets in the entire feature space, an adaptive feature selection method based on V-shaped binary particle swarm optimization is proposed. In this method, the fitness function is constructed using the correlation information entropy. Feature subsets are regarded as individuals in a population, and the feature space is searched using V-shaped binary particle swarm optimization. The above procedure overcomes the hard constraint on the number of features, enables the combined evaluation of each subset as a whole, and improves the search ability of conventional binary particle swarm optimization. The proposed algorithm is an adaptive method with respect to the number of feature subsets. The experimental results show the advantages of optimizing the feature subsets using the V-shaped transfer function and confirm the effectiveness and efficiency of the feature subsets obtained under different classifiers. PMID:28358850

  17. A new and fast image feature selection method for developing an optimal mammographic mass detection scheme

    PubMed Central

    Tan, Maxine; Pu, Jiantao; Zheng, Bin

    2014-01-01

    Purpose: Selecting optimal features from a large image feature pool remains a major challenge in developing computer-aided detection (CAD) schemes of medical images. The objective of this study is to investigate a new approach to significantly improve efficacy of image feature selection and classifier optimization in developing a CAD scheme of mammographic masses. Methods: An image dataset including 1600 regions of interest (ROIs) in which 800 are positive (depicting malignant masses) and 800 are negative (depicting CAD-generated false positive regions) was used in this study. After segmentation of each suspicious lesion by a multilayer topographic region growth algorithm, 271 features were computed in different feature categories including shape, texture, contrast, isodensity, spiculation, local topological features, as well as the features related to the presence and location of fat and calcifications. Besides computing features from the original images, the authors also computed new texture features from the dilated lesion segments. In order to select optimal features from this initial feature pool and build a highly performing classifier, the authors examined and compared four feature selection methods to optimize an artificial neural network (ANN) based classifier, namely: (1) Phased Searching with NEAT in a Time-Scaled Framework, (2) A sequential floating forward selection (SFFS) method, (3) A genetic algorithm (GA), and (4) A sequential forward selection (SFS) method. Performances of the four approaches were assessed using a tenfold cross validation method. Results: Among these four methods, SFFS has highest efficacy, which takes 3%–5% of computational time as compared to GA approach, and yields the highest performance level with the area under a receiver operating characteristic curve (AUC) = 0.864 ± 0.034. The results also demonstrated that except using GA, including the new texture features computed from the dilated mass segments improved the AUC

  18. Glass optimization for vitrification of Hanford Site low-level tank waste

    SciTech Connect

    Feng, X.; Hrma, P.R.; Westsik, J.H. Jr.

    1996-03-01

    The radioactive defense wastes stored in 177 underground single-shell tanks (SST) and double-shell tanks (DST) at the Hanford Site will be separated into low-level and high-level fractions. One technology activity underway at PNNL is the development of glass formulations for the immobilization of the low-level tank wastes. A glass formulation strategy has been developed that describes development approaches to optimize glass compositions prior to the projected LLW vitrification facility start-up in 2005. Implementation of this strategy requires testing of glass formulations spanning a number of waste loadings, compositions, and additives over the range of expected waste compositions. The resulting glasses will then be characterized and compared to processing and performance specifications yet to be developed. This report documents the glass formulation work conducted at PNL in fiscal years 1994 and 1995 including glass formulation optimization, minor component impacts evaluation, Phase 1 and Phase 2 melter vendor glass development, liquidus temperature and crystallization kinetics determination. This report also summarizes relevant work at PNNL on high-iron glasses for Hanford tank wastes conducted through the Mixed Waste Integrated Program and work at Savannah River Technology Center to optimize glass formulations using a Plackett-Burnam experimental design.

  19. Utilizing geological and geotechnical parameters to constrain optimal siting of Mid-Atlantic Bight offshore wind projects

    NASA Astrophysics Data System (ADS)

    Ponte, Alia

    As the offshore wind energy sector expands due to government mandates, a thorough understanding of the geologic setting of potential project sites becomes an essential component in the design process. Geophysical and geotechnical parameters yield vital information on the sediments and/or rocks that are present. The variable distribution of sediments, with concomitant variations in geotechnical properties, has significant implications for the selection (e.g., monopile, suction caisson, gravity base, jacket), design, location, installation, and subsequent scouring in the vicinity of wind turbine foundations. Identifying suitable sites based on sediment types allow for optimized engineering design solutions. Because foundations represent approximately 25% of total offshore wind project expenditures, reducing foundation costs with geologic suitability in mind could significantly decrease required initial investments, thereby expediting project and industry advancement. To illustrate how geological and geotechnical data can be used to inform site selection for foundations, geophysical data were analyzed and interpreted (chirp sub-bottom profiling, side-scan sonar, and multibeam bathymetry) from the Maryland Wind Energy Area (WEA). Side-scan sonar data from the WEA show three distinct acoustic intensities; each is correlated to a general bottom sediment grain size classification (muds, muddy and/or shelly sand, and sand with some gravel). Chirp sub-bottom profiles reveal the continuity and thicknesses of various depositional layers including paleochannel systems. Paleochannels consist of heterogeneous infill; creating undesirable conditions for foundation placement. This "desktop" study provides a suitability model for how the interpretation of geophysical and geotechnical data can be used to provide constraints on, and reduce uncertainties associated with, foundation location and type selection. Results from this study revealed 5 distinct subsurface units. The oldest

  20. Self-Regulatory Strategies in Daily Life: Selection, Optimization, and Compensation and Everyday Memory Problems

    ERIC Educational Resources Information Center

    Robinson, Stephanie A.; Rickenbach, Elizabeth H.; Lachman, Margie E.

    2016-01-01

    The effective use of self-regulatory strategies, such as selection, optimization, and compensation (SOC) requires resources. However, it is theorized that SOC use is most advantageous for those experiencing losses and diminishing resources. The present study explored this seeming paradox within the context of limitations or constraints due to…

  1. Sandmeyer reaction repurposed for the site-selective, non-oxidizing radioiodination of fully-deprotected peptides: studies on the endogenous opioid peptide α-neoendorphin.

    PubMed

    Pickett, Julie E; Nagakura, Kunihiko; Pasternak, Anna R; Grinnell, Steven G; Majumdar, Susruta; Lewis, Jason S; Pasternak, Gavril W

    2013-08-01

    Standard radioiodination methods lack site-selectivity and either mask charges (Bolton-Hunter) or involve oxidative reaction conditions (chloramine-T). Opioid peptides are very sensitive to certain structural modifications, making these labeling methods untenable. In our model opioid peptide, α-neoendorphin, we replaced a tyrosyl hydroxyl with an iodine, and in cell lines stably expressing mu, delta, or kappa opioid receptors, we saw no negative effects on binding. We then optimized a repurposed Sandmeyer reaction using copper(I) catalysts with non-redoxing/non-nucleophilic ligands, bringing the radiochemical yield up to around 30%, and site-selectively incorporated radioactive iodine into this position under non-oxidizing reaction conditions, which should be broadly compatible with most peptides. The (125)I- and (131)I-labeled versions of the compound bound with high affinity to opioid receptors in mouse brain homogenates, thus demonstrating the general utility of the labeling strategy and of the peptide for exploring opioid binding sites.

  2. Optimal central-place foraging by beavers: Tree-size selection in relation to defensive chemicals of quaking aspen.

    PubMed

    Basey, John M; Jenkins, Stephen H; Busher, Peter E

    1988-07-01

    At a newly occupied pond, beavers preferentially felled aspen smaller than 7.5 cm in diameter and selected against larger size classes. After one year of cutting, 10% of the aspen had been cut and 14% of the living aspen exhibited the juvenile growth form. A phenolic compound which may act as a deterrent to beavers was found in low concentrations in aspen bark, and there was no significant regression of relative concentration of this compound on tree diameter. At a pond which had been intermittently occupied by beavers for over 20 years, beavers selected against aspen smaller than 4.5 cm in diameter, and selected in favor of aspen larger than 19.5 cm in diameter. After more than 28 years of cutting at this site, 51% of the aspen had been cut and 49% of the living aspen were juvenileform. The phenolic compound was found in significantly higher concentrations in aspen bark than at the newly occupied site, and there was a significant negative regression of relative concentration on tree diameter. The results of this study show that responses to browsing by trees place constraints on the predictive value of standard energy-based optimal foraging models, and limitations on the use of such models. Future models should attempt to account for inducible responses of plants to damage and increases in concentrations of secondary metabolites through time.

  3. Selective Segmentation for Global Optimization of Depth Estimation in Complex Scenes

    PubMed Central

    Liu, Sheng; Jin, Haiqiang; Mao, Xiaojun; Zhai, Binbin; Zhan, Ye; Feng, Xiaofei

    2013-01-01

    This paper proposes a segmentation-based global optimization method for depth estimation. Firstly, for obtaining accurate matching cost, the original local stereo matching approach based on self-adapting matching window is integrated with two matching cost optimization strategies aiming at handling both borders and occlusion regions. Secondly, we employ a comprehensive smooth term to satisfy diverse smoothness request in real scene. Thirdly, a selective segmentation term is used for enforcing the plane trend constraints selectively on the corresponding segments to further improve the accuracy of depth results from object level. Experiments on the Middlebury image pairs show that the proposed global optimization approach is considerably competitive with other state-of-the-art matching approaches. PMID:23766717

  4. Comparison of DNA binding and integration half-site selection by avian myeloblastosis virus integrase.

    PubMed Central

    Grandgenett, D P; Inman, R B; Vora, A C; Fitzgerald, M L

    1993-01-01

    Insertion of the linear retrovirus DNA genome into the host DNA by the virus-encoded integrase (IN) is essential for efficient replication. We devised an efficient virus-like DNA plasmid integration assay which mimics the standard oligonucleotide assay for integration. It permitted us to study, by electron microscopy and sequence analysis, insertion of a single long terminal repeat terminus (LTR half-site) of one plasmid into another linearized plasmid. The reaction was catalyzed by purified avian myeloblastosis virus IN in the presence of Mg2+. The recombinant molecules were easily visualized and quantitated by agarose gel electrophoresis. Agarose gel-purified recombinants could be genetically selected by transformation of ligated recombinants into Escherichia coli HB101 cells. Electron microscopy also permitted the identification and localization of IN-DNA complexes on the virus-like substrate in the absence of the joining reaction. Intramolecular and intermolecular DNA looping by IN was visualized. Although IN preferentially bound to AT-rich regions in the absence of the joining reaction, there was a bias towards GC-rich regions for the joining reaction. Alignment of 70 target site sequences 5' of the LTR half-site insertions with 68 target sites previously identified for the concerted insertion of both LTR termini (LTR full-site reaction) indicated similar GC inflection patterns with both insertional events. Comparison of the data suggested that IN recognized only half of the target sequences necessary for integration with the LTR half-site reaction. Images PMID:8474165

  5. A stochastic method for optimal location of groundwater monitoring sites at aquifer scale

    NASA Astrophysics Data System (ADS)

    Barca, E.; Passarella, G.

    2009-04-01

    With the growth of public environmental awareness and the improvement in national and EU legislation regarding the environment, monitoring assumed great importance in the frame of all managerial activities related to territories. In particular, recently, a number of public environmental agencies have invested great resources in planning and operating improvements on existing monitoring networks within their regions. In this framework, and, at the light of the Water Framework Directive, the optimal monitoring of the qualitative and quantitative state of groundwater becomes a priority, particularly, when severe economic constraints must be imposed and the territory to be monitored is quite wide. There are a lot of reasons justifying the optimal extension of a monitoring network. In fact, a modest coverage of the monitored area often makes impossible to provide the manager with a sufficient knowledge for decision-making processes. In general, monitoring networks are characterized by a scarce number of existing wells, irregularly spread over the considered area. This is a typical case of optimization and it may be solved seeking among existing, but unused, wells, all and only those able to make the monitoring network coverage, the most uniform among any arrangement. Using existing wells as new monitoring sites, allows one to drastically reduce the needed budget. In this paper, a four step method, based on simulated annealing, has been implemented with the aim of identifying scarcely monitored zones within the groundwater system boundaries. The steps are the following: I. Define aquifer boundaries, number and location of the existing monitoring sites and number and location of candidate new monitoring sites. Any constraint about the network size, and wells' location and characteristics need also to be identified at this step; II. Carry out stochastic simulations producing a large number of possible realizations of the improved monitoring network and choose the transient

  6. Site-Selective Mott Transition in a Quasi-One-Dimensional Vanadate V6 O13

    NASA Astrophysics Data System (ADS)

    Shimizu, Yasuhiro; Aoyama, Satoshi; Jinno, Takaaki; Itoh, Masayuki; Ueda, Yutaka

    2015-04-01

    The microscopic mechanism of the metal-insulator transition is studied by orbital-resolved 51V NMR spectroscopy in a prototype of the quasi-one-dimensional system V6 O13 . We uncover that the transition involves a site-selective d orbital order lifting twofold orbital degeneracy in one of the two VO6 chains. The other chain leaves paramagnetic moments on the singly occupied dx y orbital across the transition. The two chains respectively stabilize an orbital-assisted spin-Peierls state and an antiferromagnetic long-range order in the ground state. The site-selective Mott transition may be a source of the anomalous metal and the Mott-Peierls duality.

  7. Site-selective synthesis of Janus-type metal-organic framework composites.

    PubMed

    Yadnum, Sudarat; Roche, Jérome; Lebraud, Eric; Négrier, Philippe; Garrigue, Patrick; Bradshaw, Darren; Warakulwit, Chompunuch; Limtrakul, Jumras; Kuhn, Alexander

    2014-04-07

    Herein, bipolar electrochemistry is applied in a straightforward way to the site-selective in situ synthesis of metal-organic framework (MOF) structures, which have attracted tremendous interest in recent years because of their significant application potential, ranging from sensing to gas storage and catalysis. The novelty of the presented work is that the deposit can be intentionally confined to a defined area of a substrate without using masks or templates. The intrinsic site-selectivity of bipolar electrochemistry makes it a method of choice to generate, in a highly controlled way, hybrid particles that may have different functionalities combined on the same particle. The wireless nature of electrodeposition allows the potential for mass production of such Janus-type objects.

  8. Metal-binding sites are designed to achieve optimal mechanical and signaling properties

    PubMed Central

    Dutta, Anindita; Bahar, Ivet

    2010-01-01

    Many proteins require bound metals to achieve their function. We take advantage of increasing structural data on metal-binding proteins to elucidate three properties: the involvement of metal-binding sites in the global dynamics of the protein, predicted by elastic network models, their exposure/burial to solvent, and their signal-processing properties indicated by Markovian stochastics analysis. Systematic analysis of a dataset of 145 structures reveals that the residues that coordinate metal ions enjoy remarkably efficient and precise signal transduction properties. These properties are rationalized in terms of their physical properties: participation in hinge sites that control the softest modes collectively accessible to the protein and occupancy of central positions minimally exposed to solvent. Our observations suggest that metal-binding sites may have been evolutionary selected to achieve optimum allosteric communication. They also provide insights into basic principles for designing metal-binding sites, which are verified to be met by recently designed de novo metal-binding proteins. PMID:20826340

  9. The Underpotential Deposition of Copper on Pt(311): Site Selective Deposition and Anion Effects

    DTIC Science & Technology

    1994-03-14

    AD-A278 022 OFFICE OF NAVAL RESEARCH CONTRACT N00014-84-k-0656/PP0002 R & T Code 4133034 Technical Report #36 The Underpotential Deposition of Copper...Include Security Clauffication) The Underpotential Deposition of Copper on Pt(311): Site Selective Deposition and Anion Effects 𔃼 OERSONAL AUTHOR(S...Alacant, Spain ABSTRACT The underpotential deposition of copper on Pt(31 1)=Pt[2(111 )x(100)] stepped surfaces has been studied and the results are compared

  10. Direct site-selective arylation of enamides via a decarboxylative cross-coupling reaction.

    PubMed

    Gigant, Nicolas; Chausset-Boissarie, Laëtitia; Gillaizeau, Isabelle

    2013-02-15

    An efficient Pd-catalyzed decarboxylative cross-coupling reaction of simple enamides was achieved. Depending on the choice of the nitrogen-protecting group, a site-selective synthesis of mono- or diarylated framework(s) was performed under mild conditions. This unprecedented reactivity could be applied to the synthesis of a range of 2- or 2,4-diarylated nitrogen-containing bioactive derivatives.

  11. Preparation of Asymmetric Nanostructures through Site SelectiveModification of Tetrapods

    SciTech Connect

    Liu, Haitao; Alivisatos, A. Paul

    2004-09-09

    CdTe tetrapods have been deposited on a substrate and partially coated with a protective polymer layer, exposing just one arm. The exposed arm was then decorated with Au nanoparticles in a site selective fashion. The modified arms were readily broken off from the remainder of the tetrapods and released from the substrate, yielding CdTe nanorods asymmetrically modified with Au nanoparticles. These nanostructures with reduced symmetry may show interesting optoelectronic properties.

  12. [Characteristics of ion selective electrodes with hetero-poly anion sites].

    PubMed

    Nie, L H; Ma, W L; Xiang, X C; Yao, S Z

    1989-01-01

    Drug ion-selective electrodes made with hetero-poly anion as exchange site exhibit better performances than the respective electrodes of conventional tetraphenylboron type, yielding low detection limits and fast responses. Functions of propantheline, berberine, dibazol, thiamine, streptomycin, moroxydine, tetracycline, oxytetracycline, doxycycline, erythromycin, carbetapentane, benzydamine, tetramisole and trifluoperazine electrodes are reported. The electrodes can be used in potentiometric determinations of the respective drugs in aqueous solutions, urine and mixture of water and organic solvents.

  13. Siting-selection study for the Soyland Power Cooperative, Inc. , compressed-air energy-storage system (CAES)

    SciTech Connect

    Not Available

    1982-01-01

    A method used for siting a compressed air energy storage (CAES) system using geotechnical and environmental criteria is explained using the siting of a proposed 220 MW water-compensated CAES plant in Illinois as an example. Information is included on the identification and comparative ranking of 28 geotechnically and environmental sites in Illinois, the examination of fatal flaws, e.g., mitigation, intensive studies, costly studies, permit denials, at 7 sites; and the selection of 3 sites for further geological surveying. (LCL)

  14. Selection and Assessment of Predictions of the Mars Pathfinder Landing Site

    NASA Technical Reports Server (NTRS)

    Golombek, M. P.; Moore, H. J.; Haldemann, A. F. C.; Cook, R. A.; Parker, T. J.; Schofield, J. T.

    1998-01-01

    The successful landing of the Mars Pathfinder spacecraft on Mars allows the review of the process of selecting the landing site and assessing predictions made for the site based on Viking and Earth-based data. Selection of the landing site for Mars Pathfinder was a two-phase process. The first phase took place from October 1993 to June 1994 and involved: initial identification of engineering constraints, definition of environmental conditions at the site for spacecraft design, and evaluation of the scientific potential of different landing sites. This phase culminated with the first "Mars Pathfinder Landing Site Workshop", held at the Lunar and Planetary Institute in Houston, Texas on April 18-19, 1994, in which suggested approaches and landing sites were solicited from the entire scientific community. A preliminary site was selected by the project for design purposes in June 1994. The second phase took place from July 1994 to March 1996 and involved: developing criteria for evaluating site safety using images and remote sensing data, testing of the spacecraft and landing subsystems (with design improvements) to establish quantitative engineering constraints on landing site characteristics, evaluating all potential landing sites on Mars, and certification of the site by the project. This phase included a second open workshop, "Mars Pathfinder Landing Site Workshop II: Characteristics of the Ares Vallis Region and Field Trips in the Channeled Scabland, Washington" held in Spokane and Moses Lake September 24-30, 1995 and formal acceptance of the site by NASA Headquarters. Engineering constraints on Pathfinder landing sites were developed from the initial design of the spacecraft and the entry, descent and landing scenario. The site must be within 5 degrees of the subsolar latitude at the time of landing (15N for maximum solar power and flexible communications with Earth. It also must be below 0 km elevation to enable enough time for the parachute to bring the lander

  15. Selective Self-Presentation and Social Comparison Through Photographs on Social Networking Sites.

    PubMed

    Fox, Jesse; Vendemia, Megan A

    2016-10-01

    Through social media and camera phones, users enact selective self-presentation as they choose, edit, and post photographs of themselves (such as selfies) to social networking sites for an imagined audience. Photos typically focus on users' physical appearance, which may compound existing sociocultural pressures about body image. We identified users of social networking sites among a nationally representative U.S. sample (N = 1,686) and examined women's and men's photo-related behavior, including posting photos, editing photos, and feelings after engaging in upward and downward social comparison with others' photos on social networking sites. We identified some sex differences: women edited photos more frequently and felt worse after upward social comparison than men. Body image and body comparison tendency mediated these effects.

  16. Phase I (first-in-man) prophylactic vaccine's clinical trials: Selecting a clinical trial site

    PubMed Central

    Mehta, Shantanu; Goyal, Vishal; Singh, Kavita

    2015-01-01

    An appropriately equipped and staffed Phase I unit is critical for smooth conduct of a first-in-man clinical trial. The first-in-man prophylactic vaccine trial(s) requires basic infrastructure of clinical trial site, experienced and dedicated site staff and healthy adults as volunteers. The facility should have access to equipment, emergency services, laboratory, pharmacy and archiving. In terms of design, infrastructure, workflow and manpower, a Phase I unit for testing a novel vaccine or drug are quite similar. However, there are some important attributes, which should be taken into consideration, while performing pre-trial site selection for conducting phase I trial with a new or novel vaccine. PMID:25878951

  17. Predation risk induces changes in nest-site selection and clutch size in the Siberian jay

    PubMed Central

    Eggers, Sönke; Griesser, Michael; Nystrand, Magdalena; Ekman, Jan

    2005-01-01

    Life-history theory predicts that an individual should reduce its reproductive efforts by laying a smaller clutch size when high risk of nest predation reduces the value of current reproduction. Evidence in favour of this ‘nest predation hypothesis’, however, is scarce and based largely on correlative analyses. Here, we manipulated perceived risk of nest predation in the Siberian jay Perisoreus infaustus using playback involving a mixture of calls by corvid nest predators in the vicinity of nest sites. In response to being exposed to this acoustic cue simulating increased risk of nest predation, the jays chose a nest site offering more protective covering and reduced clutch size. This is the first experimental demonstration of clutch size adjustment and nest site selection as a result of phenotypic plasticity in an open nesting passerine reflecting a facultative response to the perceived risk of nest predation. PMID:16608689

  18. Characterisation of Danish Waters with EO and Modelling for Aquaculture Site Selection

    NASA Astrophysics Data System (ADS)

    Huber, Silvia; Hansen, Lars B.; Rasmussen, Mads O.; Kaas, Hanne

    2016-08-01

    The process of selecting a site for aquaculture is complex and many factors are feeding into it. Spatial information from satellites and models is highly valuable in this process. For instance, water temperature is crucial for the fish's health and feed management and chlorophyll-a concentration (chl-a) is used as a water quality indicator. Near-real time satellite information can be used for monitoring purposes and historic patterns of these variables can be included into the process of choosing a suitable site. Modelled data can be used as complementary source, for predictive purposes and during cloudy periods, when optical satellite data is unavailable. In this paper we present a concept of how information from satellites and models can feed into siting. Moreover, we compare temperature and chl-a both from satellites and models, to evaluate the quality as well as difference between these products in the Danish waters.

  19. Toward Coordinated Colloids: Site-Selective Growth of Titania on Patchy Silica Particles

    PubMed Central

    Bae, Changdeuck; Kim, Hyunchul; Montero Moreno, Josep M.; Yi, Gi-Ra; Shin, Hyunjung

    2015-01-01

    Rational synthesis of coordinated spherical colloids is reported by site-selective growth of secondary hemispherical patches on primary spherical particles with quasi-defined coordination numbers and positions. We clarify the importance of mass transport phenomena on the site-specific secondary nucleation/growth in nanoparticulate colloidal systems. By comparing ultrasonic and conventional agitation during patch growth, we found that enhanced mass transfer is the key to controlled, homogeneous transport of the molecular precursors in a solvent onto the nanoparticles. With chemically defined nucleation sites, the surfaces of spherical silica particles were modified for use as a new kind of colloid with patches at desired coordination positions. Our observations represent a significant breakthrough in colloidal chemistry and self-assembly. PMID:25797616

  20. Selection of Thermal Worst-Case Orbits via Modified Efficient Global Optimization

    NASA Technical Reports Server (NTRS)

    Moeller, Timothy M.; Wilhite, Alan W.; Liles, Kaitlin A.

    2014-01-01

    Efficient Global Optimization (EGO) was used to select orbits with worst-case hot and cold thermal environments for the Stratospheric Aerosol and Gas Experiment (SAGE) III. The SAGE III system thermal model changed substantially since the previous selection of worst-case orbits (which did not use the EGO method), so the selections were revised to ensure the worst cases are being captured. The EGO method consists of first conducting an initial set of parametric runs, generated with a space-filling Design of Experiments (DoE) method, then fitting a surrogate model to the data and searching for points of maximum Expected Improvement (EI) to conduct additional runs. The general EGO method was modified by using a multi-start optimizer to identify multiple new test points at each iteration. This modification facilitates parallel computing and decreases the burden of user interaction when the optimizer code is not integrated with the model. Thermal worst-case orbits for SAGE III were successfully identified and shown by direct comparison to be more severe than those identified in the previous selection. The EGO method is a useful tool for this application and can result in computational savings if the initial Design of Experiments (DoE) is selected appropriately.

  1. Quantitative morphometric measurements using site selective image cytometry of intact tissue.

    PubMed

    Kwon, Hyuk-Sang; Nam, Yoon Sung; Wiktor-Brown, Dominika M; Engelward, Bevin P; So, Peter T C

    2009-02-06

    Site selective two-photon tissue image cytometry has previously been successfully applied to measure the number of rare cells in three-dimensional tissue specimens up to cubic millimetres in size. However, the extension of this approach for high-throughput quantification of cellular morphological states has not been demonstrated. In this paper, we report the use of site-selective tissue image cytometry for the study of homologous recombination (HR) events during cell division in the pancreas of transgenic mice. Since HRs are rare events, recombinant cells distribute sparsely inside the organ. A detailed measurement throughout the whole tissue is thus not practical. Instead, the site selective two-photon tissue cytometer incorporates a low magnification, wide field, one-photon imaging subsystem that rapidly identifies regions of interest containing recombinant cell clusters. Subsequently, high-resolution three-dimensional assays based on two-photon microscopy can be performed only in these regions of interest. We further show that three-dimensional morphology extraction algorithms can be used to analyse the resultant high-resolution two-photon image stacks providing information not only on the frequency and the distribution of these recombinant cell clusters and their constituent cells, but also on their morphology.

  2. A zinc-binding site by negative selection induces metallodrug susceptibility in an essential chaperonin

    PubMed Central

    Cun, Shujian; Sun, Hongzhe

    2010-01-01

    GroES is an indispensable chaperonin virtually found throughout all life forms. Consequently, mutations of this protein must be critically scrutinized by natural selection. Nevertheless, the homolog from a potentially virulent gastric pathogen, Helicobacter pylori, strikingly features a histidine/cysteine-rich C terminus that shares no significant homology with other family members. Additionally, three more (H45, C51, and C53) are uniquely present in its apical domain. The statistical analyses show that these residues may have originated from negative selection, presumably driven by either dependent or independent amino acid mutations. In the absence of the C-terminal metal-binding domain, the mutant protein still exhibits a substantial capacity for zinc binding in vivo. The biochemical properties of site-directed mutants indicate that H45, C51, and C53 make up an oxidation-sensitive zinc-binding site that may donate the bound metal to a zinc acceptor. Of interest, bismuth antiulcer drugs strongly bind at this site (Kd of approximately 7 × 10-26 M), replacing the bound zinc and consequently inducing the disruption of the quaternary structure. Because biological features by negative selection are usually inert to change during evolution, this study sheds light on a promising field whereby medicines can be designed or improved to specifically target the residues that uniquely evolved in pathogenic proteins so as to retard the emergence of drug resistance. PMID:20194796

  3. Risky business: Site selection by Acadian Flycatchers under threat of nest predation and brood parasitism

    USGS Publications Warehouse

    HazIer, K.R.; Cooper, R.J.; Twedt, D.J.

    2006-01-01

    Habitat quality is determined not only by habitat structure and the availability of resources, but also by competitors, cooperators, predators, and parasites. We hypothesized that, for passerines, minimizing risk from avian nest predators and brood parasites is an important factor in selecting a breeding site. Through the early part of two breeding seasons, we spot-mapped locations of Acadian Flycatchers (Empidonax virescens, territory selectors), Red-bellied Woodpeckers (Melanerpes carolinus, nest predators) and Brown-headed Cowbirds (Molothrus ater, brood parasites) in a 56-ha study area within an extensive bottomland hardwood forest. We were thereby able to determine the order of flycatcher territory settlement and nest initiation in relation to risk of predation and parasitism, while accounting for habitat structure. Male settlement was influenced by both habitat structure and risk avoidance. However, risk trom woodpeckers was relatively more important in the first season and risk from cowbirds in the second, evidently due to differences in the relative abundance of predator and brood-parasite in each year. For male flycatchers, settlement choices appear to be flexible in the face of changing 'risk landscapes.' For females, habitat structure was the most important predictor of nest site selection. Even so, there was evidence that females avoided cowbirds. Surprisingly, nest site selection was positively associated with woodpecker abundance in the first season when woodpeckers were present in greater numbers. Possible explanations for this contradictory result are discussed.

  4. Selective small molecule inhibitor of the Mycobacterium tuberculosis fumarate hydratase reveals an allosteric regulatory site

    PubMed Central

    Kasbekar, Monica; Fischer, Gerhard; Mott, Bryan T.; Yasgar, Adam; Hyvönen, Marko; Boshoff, Helena I. M.; Abell, Chris; Barry, Clifton E.; Thomas, Craig J.

    2016-01-01

    Enzymes in essential metabolic pathways are attractive targets for the treatment of bacterial diseases, but in many cases, the presence of homologous human enzymes makes them impractical candidates for drug development. Fumarate hydratase, an essential enzyme in the tricarboxylic acid (TCA) cycle, has been identified as one such potential therapeutic target in tuberculosis. We report the discovery of the first small molecule inhibitor, to our knowledge, of the Mycobacterium tuberculosis fumarate hydratase. A crystal structure at 2.0-Å resolution of the compound in complex with the protein establishes the existence of a previously unidentified allosteric regulatory site. This allosteric site allows for selective inhibition with respect to the homologous human enzyme. We observe a unique binding mode in which two inhibitor molecules interact within the allosteric site, driving significant conformational changes that preclude simultaneous substrate and inhibitor binding. Our results demonstrate the selective inhibition of a highly conserved metabolic enzyme that contains identical active site residues in both the host and the pathogen. PMID:27325754

  5. Summary and Comparison of Multiphase Streambed Scour Analysis at Selected Bridge Sites in Alaska

    USGS Publications Warehouse

    Conaway, Jeffrey S.

    2004-01-01

    The U.S. Geological Survey and the Alaska Department of Transportation and Public Facilities undertook a cooperative multiphase study of streambed scour at selected bridges in Alaska beginning in 1994. Of the 325 bridges analyzed for susceptibility to scour in the preliminary phase, 54 bridges were selected for a more intensive analysis that included site investigations. Cross-section geometry and hydraulic properties for each site in this study were determined from field surveys and bridge plans. Water-surface profiles were calculated for the 100- and 500-year floods using the Hydrologic Engineering Center?s River Analysis System and scour depths were calculated using methods recommended by the Federal Highway Administration. Computed contraction-scour depths for the 100- and 500-year recurrence-interval discharges exceeded 5 feet at six bridges, and pier-scour depths exceeded 10 feet at 24 bridges. Complex pier-scour computations were made at 10 locations where the computed contraction-scour depths would expose pier footings. Pressure scour was evaluated at three bridges where the modeled flood water-surface elevations intersected the bridge structure. Site investigation at the 54 scour-critical bridges was used to evaluate the effectiveness of the preliminary scour analysis. Values for channel-flow angle of attack and approach-channel width were estimated from bridge survey plans for the preliminary study and were measured during a site investigation for this study. These two variables account for changes in scour depths between the preliminary analysis and subsequent reanalysis for most sites. Site investigation is needed for best estimates of scour at bridges with survey plans that indicate a channel-flow angle of attack and for locations where survey plans did not include sufficient channel geometry upstream of the bridge.

  6. A general method to select representative models for decision making and optimization under uncertainty

    NASA Astrophysics Data System (ADS)

    Shirangi, Mehrdad G.; Durlofsky, Louis J.

    2016-11-01

    The optimization of subsurface flow processes under geological uncertainty technically requires flow simulation to be performed over a large set of geological realizations for each function evaluation at every iteration of the optimizer. Because flow simulation over many permeability realizations (only permeability is considered to be uncertain in this study) may entail excessive computation, simulations are often performed for only a subset of 'representative' realizations. It is however challenging to identify a representative subset that provides flow statistics in close agreement with those from the full set, especially when the decision parameters (e.g., time-varying well pressures, well locations) are unknown a priori, as they are in optimization problems. In this work, we introduce a general framework, based on clustering, for selecting a representative subset of realizations for use in simulations involving 'new' sets of decision parameters. Prior to clustering, each realization is represented by a low-dimensional feature vector that contains a combination of permeability-based and flow-based quantities. Calculation of flow-based features requires the specification of a (base) flow problem and simulation over the full set of realizations. Permeability information is captured concisely through use of principal component analysis. By computing the difference between the flow response for the subset and the full set, we quantify the performance of various realization-selection methods. The impact of different weightings for flow and permeability information in the cluster-based selection procedure is assessed for a range of examples involving different types of decision parameters. These decision parameters are generated either randomly, in a manner that is consistent with the solutions proposed in global stochastic optimization procedures such as GA and PSO, or through perturbation around a base case, consistent with the solutions considered in pattern search

  7. A Novel Method of Failure Sample Selection for Electrical Systems Using Ant Colony Optimization

    PubMed Central

    Tian, Shulin; Yang, Chenglin; Liu, Cheng

    2016-01-01

    The influence of failure propagation is ignored in failure sample selection based on traditional testability demonstration experiment method. Traditional failure sample selection generally causes the omission of some failures during the selection and this phenomenon could lead to some fearful risks of usage because these failures will lead to serious propagation failures. This paper proposes a new failure sample selection method to solve the problem. First, the method uses a directed graph and ant colony optimization (ACO) to obtain a subsequent failure propagation set (SFPS) based on failure propagation model and then we propose a new failure sample selection method on the basis of the number of SFPS. Compared with traditional sampling plan, this method is able to improve the coverage of testing failure samples, increase the capacity of diagnosis, and decrease the risk of using. PMID:27738424

  8. Optimal location selection for the installation of urban green roofs considering honeybee habitats along with socio-economic and environmental effects.

    PubMed

    Gwak, Jae Ha; Lee, Bo Kyeong; Lee, Won Kyung; Sohn, So Young

    2017-03-15

    This study proposes a new framework for the selection of optimal locations for green roofs to achieve a sustainable urban ecosystem. The proposed framework selects building sites that can maximize the benefits of green roofs, based not only on the socio-economic and environmental benefits to urban residents, but also on the provision of urban foraging sites for honeybees. The framework comprises three steps. First, building candidates for green roofs are selected considering the building type. Second, the selected building candidates are ranked in terms of their expected socio-economic and environmental effects. The benefits of green roofs are improved energy efficiency and air quality, reduction of urban flood risk and infrastructure improvement costs, reuse of storm water, and creation of space for education and leisure. Furthermore, the estimated cost of installing green roofs is also considered. We employ spatial data to determine the expected effects of green roofs on each building unit, because the benefits and costs may vary depending on the location of the building. This is due to the heterogeneous spatial conditions. In the third step, the final building sites are proposed by solving the maximal covering location problem (MCLP) to determine the optimal locations for green roofs as urban honeybee foraging sites. As an illustrative example, we apply the proposed framework in Seoul, Korea. This new framework is expected to contribute to sustainable urban ecosystems.

  9. A multi-site study on medical school selection, performance, motivation and engagement.

    PubMed

    Wouters, A; Croiset, G; Schripsema, N R; Cohen-Schotanus, J; Spaai, G W G; Hulsman, R L; Kusurkar, R A

    2017-05-01

    Medical schools seek ways to improve their admissions strategies, since the available methods prove to be suboptimal for selecting the best and most motivated students. In this multi-site cross-sectional questionnaire study, we examined the value of (different) selection procedures compared to a weighted lottery procedure, which includes direct admission based on top pre-university grade point averages (≥8 out of 10; top-pu-GPA). We also considered whether students had participated in selection, prior to being admitted through weighted lottery. Year-1 (pre-clinical) and Year-4 (clinical) students completed standard validated questionnaires measuring quality of motivation (Academic Self-regulation Questionnaire), strength of motivation (Strength of Motivation for Medical School-Revised) and engagement (Utrecht Work Engagement Scale-Student). Performance data comprised GPA and course credits in Year-1 and clerkship performance in Year-4. Regression analyses were performed. The response rate was 35% (387 Year-1 and 273 Year-4 students). Top-pu-GPA students outperformed selected students. Selected Year-1 students reported higher strength of motivation than top-pu-GPA students. Selected students did not outperform or show better quality of motivation and engagement than lottery-admitted students. Participation in selection was associated with higher engagement and better clerkship performance in Year-4. GPA, course credits and strength of motivation in Year-1 differed between students admitted through different selection procedures. Top-pu-GPA students perform best in the medical study. The few and small differences found raise questions about the added value of an extensive selection procedure compared to a weighted lottery procedure. Findings have to be interpreted with caution because of a low response rate and small group sizes.

  10. Tricyclic covalent inhibitors selectively target Jak3 through an active site thiol.

    PubMed

    Goedken, Eric R; Argiriadi, Maria A; Banach, David L; Fiamengo, Bryan A; Foley, Sage E; Frank, Kristine E; George, Jonathan S; Harris, Christopher M; Hobson, Adrian D; Ihle, David C; Marcotte, Douglas; Merta, Philip J; Michalak, Mark E; Murdock, Sara E; Tomlinson, Medha J; Voss, Jeffrey W

    2015-02-20

    The action of Janus kinases (JAKs) is required for multiple cytokine signaling pathways, and as such, JAK inhibitors hold promise for treatment of autoimmune disorders, including rheumatoid arthritis, inflammatory bowel disease, and psoriasis. However, due to high similarity in the active sites of the four members (Jak1, Jak2, Jak3, and Tyk2), developing selective inhibitors within this family is challenging. We have designed and characterized substituted, tricyclic Jak3 inhibitors that selectively avoid inhibition of the other JAKs. This is accomplished through a covalent interaction between an inhibitor containing a terminal electrophile and an active site cysteine (Cys-909). We found that these ATP competitive compounds are irreversible inhibitors of Jak3 enzyme activity in vitro. They possess high selectivity against other kinases and can potently (IC50 < 100 nm) inhibit Jak3 activity in cell-based assays. These results suggest irreversible inhibitors of this class may be useful selective agents, both as tools to probe Jak3 biology and potentially as therapies for autoimmune diseases.

  11. Science-Policy Interactions in MPA Site Selection in the Dutch Part of the North Sea

    NASA Astrophysics Data System (ADS)

    van Haastrecht, Eline K.; Toonen, Hilde M.

    2011-04-01

    At the 7th conference of the parties to the Convention on Biological Diversity (CBD-COP7, Kuala Lumpur, 2004) it was agreed to establish a global network of marine and coastal protected areas by 2012. The defined objectives of this MPA-network are based on the ecosystem approach: to protect biodiversity and other ecological values, and to ensure sustainable use. The (inter)national policy guidelines state that the selection of MPAs should be based on scientific information and ecological criteria only. As a signatory to the Convention, the Netherlands is now faced with meeting this obligation, and the process of designating the first Marine Protected Areas (MPAs) in the Dutch part of the North Sea is currently in progress. We focus on the science-policy interactions that are part of this Dutch MPA selection process. By taking a closer look at the contemporary site selection process as well as its historical background, we show that ecological, socio-economic and political considerations cannot always be easily separated. Uncertainty is high and the ultimate selection and delimitation of candidate sites rather seems to be the result of a balancing act between ecological, socio-economic and political interests, in which scientific and policy guiding procedures blend with ad-hoc political decision making, and with expert judgment in cases where data is lacking. As such, this paper presents an example of present-day environmental policy making in action.

  12. Tricyclic Covalent Inhibitors Selectively Target Jak3 through an Active Site Thiol*

    PubMed Central

    Goedken, Eric R.; Argiriadi, Maria A.; Banach, David L.; Fiamengo, Bryan A.; Foley, Sage E.; Frank, Kristine E.; George, Jonathan S.; Harris, Christopher M.; Hobson, Adrian D.; Ihle, David C.; Marcotte, Douglas; Merta, Philip J.; Michalak, Mark E.; Murdock, Sara E.; Tomlinson, Medha J.; Voss, Jeffrey W.

    2015-01-01

    The action of Janus kinases (JAKs) is required for multiple cytokine signaling pathways, and as such, JAK inhibitors hold promise for treatment of autoimmune disorders, including rheumatoid arthritis, inflammatory bowel disease, and psoriasis. However, due to high similarity in the active sites of the four members (Jak1, Jak2, Jak3, and Tyk2), developing selective inhibitors within this family is challenging. We have designed and characterized substituted, tricyclic Jak3 inhibitors that selectively avoid inhibition of the other JAKs. This is accomplished through a covalent interaction between an inhibitor containing a terminal electrophile and an active site cysteine (Cys-909). We found that these ATP competitive compounds are irreversible inhibitors of Jak3 enzyme activity in vitro. They possess high selectivity against other kinases and can potently (IC50 < 100 nm) inhibit Jak3 activity in cell-based assays. These results suggest irreversible inhibitors of this class may be useful selective agents, both as tools to probe Jak3 biology and potentially as therapies for autoimmune diseases. PMID:25552479

  13. Polybrominated diphenyl ethers (PBDEs) in leachates from selected landfill sites in South Africa

    SciTech Connect

    Odusanya, David O.; Okonkwo, Jonathan O. Botha, Ben

    2009-01-15

    The last few decades have seen dramatic growth in the scale of production and the use of polybrominated diphenyl ethers (PBDEs) as flame retardants. Consequently, PBDEs such as BDE -28, -47, -66, -71, -75, -77, -85, -99, -100, -119, -138, -153, -154, and -183 have been detected in various environmental matrices. Generally, in South Africa, once the products containing these chemicals have outlived their usefulness, they are discarded into landfill sites. Consequently, the levels of PBDEs in leachates from landfill sites may give an indication of the general exposure and use of these compounds. The present study was aimed at determining the occurrence and concentrations of most common PBDEs in leachates from selected landfill sites. The extraction capacities of the solvents were also tested. Spiked landfill leachate samples were used for the recovery tests. Separation and determination of the PBDE congeners were carried out with a gas chromatograph equipped with Ni{sup 63} electron capture detector. The mean percentage recoveries ranged from 63% to 108% (n = 3) for landfill leachate samples with petroleum ether giving the highest percentage extraction. The mean concentrations of PBDEs obtained ranged from ND to 2670 pg l{sup -1}, ND to 6638 pg l{sup -1}, ND to 7230 pg l{sup -1}, 41 to 4009 pg l{sup -1}, 90 to 9793 pg l{sup -1} for the Garankuwa, Hatherly, Kwaggarsrand, Soshanguve and Temba landfill sites, respectively. Also BDE -28, -47, -71 and BDE-77 were detected in the leachate samples from all the landfill sites; and all the congeners were detected in two of the oldest landfill sites. The peak concentrations were recorded for BDE-47 at three sites and BDE-71 and BDE-75 at two sites. The highest concentration, 9793 {+-} 1.5 pg l{sup -1}, was obtained for the Temba landfill site with the highest BOD value. This may suggest some influence of organics on the level of PBDEs. Considering the leaching characteristics of brominated flame retardants, there is a high

  14. Dynamic Disturbance Processes Create Dynamic Lek Site Selection in a Prairie Grouse

    PubMed Central

    Hovick, Torre J.; Allred, Brady W.; Elmore, R. Dwayne; Fuhlendorf, Samuel D.; Hamilton, Robert G.; Breland, Amber

    2015-01-01

    It is well understood that landscape processes can affect habitat selection patterns, movements, and species persistence. These selection patterns may be altered or even eliminated as a result of changes in disturbance regimes and a concomitant management focus on uniform, moderate disturbance across landscapes. To assess how restored landscape heterogeneity influences habitat selection patterns, we examined 21 years (1991, 1993–2012) of Greater Prairie-Chicken (Tympanuchus cupido) lek location data in tallgrass prairie with restored fire and grazing processes. Our study took place at The Nature Conservancy’s Tallgrass Prairie Preserve located at the southern extent of Flint Hills in northeastern Oklahoma. We specifically addressed stability of lek locations in the context of the fire-grazing interaction, and the environmental factors influencing lek locations. We found that lek locations were dynamic in a landscape with interacting fire and grazing. While previous conservation efforts have treated leks as stable with high site fidelity in static landscapes, a majority of lek locations in our study (i.e., 65%) moved by nearly one kilometer on an annual basis in this dynamic setting. Lek sites were in elevated areas with low tree cover and low road density. Additionally, lek site selection was influenced by an interaction of fire and patch edge, indicating that in recently burned patches, leks were located near patch edges. These results suggest that dynamic and interactive processes such as fire and grazing that restore heterogeneity to grasslands do influence habitat selection patterns in prairie grouse, a phenomenon that is likely to apply throughout the Greater Prairie-Chicken’s distribution when dynamic processes are restored. As conservation moves toward restoring dynamic historic disturbance patterns, it will be important that siting and planning of anthropogenic structures (e.g., wind energy, oil and gas) and management plans not view lek locations as

  15. Dynamic Disturbance Processes Create Dynamic Lek Site Selection in a Prairie Grouse.

    PubMed

    Hovick, Torre J; Allred, Brady W; Elmore, R Dwayne; Fuhlendorf, Samuel D; Hamilton, Robert G; Breland, Amber

    2015-01-01

    It is well understood that landscape processes can affect habitat selection patterns, movements, and species persistence. These selection patterns may be altered or even eliminated as a result of changes in disturbance regimes and a concomitant management focus on uniform, moderate disturbance across landscapes. To assess how restored landscape heterogeneity influences habitat selection patterns, we examined 21 years (1991, 1993-2012) of Greater Prairie-Chicken (Tympanuchus cupido) lek location data in tallgrass prairie with restored fire and grazing processes. Our study took place at The Nature Conservancy's Tallgrass Prairie Preserve located at the southern extent of Flint Hills in northeastern Oklahoma. We specifically addressed stability of lek locations in the context of the fire-grazing interaction, and the environmental factors influencing lek locations. We found that lek locations were dynamic in a landscape with interacting fire and grazing. While previous conservation efforts have treated leks as stable with high site fidelity in static landscapes, a majority of lek locations in our study (i.e., 65%) moved by nearly one kilometer on an annual basis in this dynamic setting. Lek sites were in elevated areas with low tree cover and low road density. Additionally, lek site selection was influenced by an interaction of fire and patch edge, indicating that in recently burned patches, leks were located near patch edges. These results suggest that dynamic and interactive processes such as fire and grazing that restore heterogeneity to grasslands do influence habitat selection patterns in prairie grouse, a phenomenon that is likely to apply throughout the Greater Prairie-Chicken's distribution when dynamic processes are restored. As conservation moves toward restoring dynamic historic disturbance patterns, it will be important that siting and planning of anthropogenic structures (e.g., wind energy, oil and gas) and management plans not view lek locations as static

  16. Single-site trinuclear copper oxygen clusters in mordenite for selective conversion of methane to methanol

    PubMed Central

    Grundner, Sebastian; Markovits, Monica A.C.; Li, Guanna; Tromp, Moniek; Pidko, Evgeny A.; Hensen, Emiel J.M.; Jentys, Andreas; Sanchez-Sanchez, Maricruz; Lercher, Johannes A.

    2015-01-01

    Copper-exchanged zeolites with mordenite structure mimic the nuclearity and reactivity of active sites in particulate methane monooxygenase, which are enzymes able to selectively oxidize methane to methanol. Here we show that the mordenite micropores provide a perfect confined environment for the highly selective stabilization of trinuclear copper-oxo clusters that exhibit a high reactivity towards activation of carbon–hydrogen bonds in methane and its subsequent transformation to methanol. The similarity with the enzymatic systems is also implied from the similarity of the reversible rearrangements of the trinuclear clusters occurring during the selective transformations of methane along the reaction path towards methanol, in both the enzyme system and copper-exchanged mordenite. PMID:26109507

  17. Catalytic site remodelling of the DOT1L methyltransferase by selective inhibitors

    SciTech Connect

    Yu, Wenyu; Chory, Emma J.; Wernimont, Amy K.; Tempel, Wolfram; Scopton, Alex; Federation, Alexander; Marineau, Jason J.; Qi, Jun; Barsyte-Lovejoy, Dalia; Yi, Joanna; Marcellus, Richard; Iacob, Roxana E.; Engen, John R.; Griffin, Carly; Aman, Ahmed; Wienholds, Erno; Li, Fengling; Pineda, Javier; Estiu, Guillermina; Shatseva, Tatiana; Hajian, Taraneh; Al-awar, Rima; Dick, John E.; Vedadi, Masoud; Brown, Peter J.; Arrowsmith, Cheryl H.; Bradner, James E.; Schapira, Matthieu

    2012-12-18

    Selective inhibition of protein methyltransferases is a promising new approach to drug discovery. An attractive strategy towards this goal is the development of compounds that selectively inhibit binding of the cofactor, S-adenosylmethionine, within specific protein methyltransferases. Here we report the three-dimensional structure of the protein methyltransferase DOT1L bound toEPZ004777, the first S-adenosylmethionine-competitive inhibitor of a protein methyltransferase with in vivo efficacy. This structure and those of four new analogues reveal remodelling of the catalytic site. EPZ004777 and a brominated analogue, SGC0946, inhibit DOT1L in vitro and selectively kill mixed lineage leukaemia cells, in which DOT1L is aberrantly localized via interaction with an oncogenic MLL fusion protein. These data provide important new insight into mechanisms of cell-active S-adenosylmethionine-competitive protein methyltransferase inhibitors, and establish a foundation for the further development of drug-like inhibitors of DOT1L for cancer therapy.

  18. 41 CFR 301-74.19 - What records must we maintain to document the selection of a conference site?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... maintain to document the selection of a conference site? 301-74.19 Section 301-74.19 Public Contracts and Property Management Federal Travel Regulation System TEMPORARY DUTY (TDY) TRAVEL ALLOWANCES AGENCY... document the selection of a conference site? For each conference you sponsor or fund, in whole or in...

  19. 41 CFR 301-74.19 - What records must we maintain to document the selection of a conference site?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... maintain to document the selection of a conference site? 301-74.19 Section 301-74.19 Public Contracts and Property Management Federal Travel Regulation System TEMPORARY DUTY (TDY) TRAVEL ALLOWANCES AGENCY... document the selection of a conference site? For each conference you sponsor or fund, in whole or in...

  20. 41 CFR 301-74.19 - What records must we maintain to document the selection of a conference site?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... maintain to document the selection of a conference site? 301-74.19 Section 301-74.19 Public Contracts and... RESPONSIBILITIES 74-CONFERENCE PLANNING Agency Responsibilities § 301-74.19 What records must we maintain to document the selection of a conference site? For each conference you sponsor or fund, in whole or in...