Sample records for optimal sites selection

  1. Analysis Methodology for Optimal Selection of Ground Station Site in Space Missions

    NASA Astrophysics Data System (ADS)

    Nieves-Chinchilla, J.; Farjas, M.; Martínez, R.

    2013-12-01

    Optimization of ground station sites is especially important in complex missions that include several small satellites (clusters or constellations) such as the QB50 project, where one ground station would be able to track several spatial vehicles, even simultaneously. In this regard the design of the communication system has to carefully take into account the ground station site and relevant signal phenomena, depending on the frequency band. To propose the optimal location of the ground station, these aspects become even more relevant to establish a trusted communication link due to the ground segment site in urban areas and/or selection of low orbits for the space segment. In addition, updated cartography with high resolution data of the location and its surroundings help to develop recommendations in the design of its location for spatial vehicles tracking and hence to improve effectiveness. The objectives of this analysis methodology are: completion of cartographic information, modelling the obstacles that hinder communication between the ground and space segment and representation in the generated 3D scene of the degree of impairment in the signal/noise of the phenomena that interferes with communication. The integration of new technologies of geographic data capture, such as 3D Laser Scan, determine that increased optimization of the antenna elevation mask, in its AOS and LOS azimuths along the horizon visible, maximizes visibility time with spatial vehicles. Furthermore, from the three-dimensional cloud of points captured, specific information is selected and, using 3D modeling techniques, the 3D scene of the antenna location site and surroundings is generated. The resulting 3D model evidences nearby obstacles related to the cartographic conditions such as mountain formations and buildings, and any additional obstacles that interfere with the operational quality of the antenna (other antennas and electronic devices that emit or receive in the same bandwidth

  2. Operational Site Selection for Unmanned Aircraft

    DTIC Science & Technology

    2011-06-01

    eliminate unsuitable areas, the Op Site Selection process must first consider landcover , terrain, and specifications for one or more UAS platforms...areas, the OSS process must first consider landcover , terrain, and specifi- cations for one or more UAS platforms. To select the most optimal sites, the...by landcover , ERDC/CERL TR-11-16 2 soil type, slope, and aspect. The individual terrain units are pre- determined and delineated by a separate

  3. Urban Rain Gauge Siting Selection Based on Gis-Multicriteria Analysis

    NASA Astrophysics Data System (ADS)

    Fu, Yanli; Jing, Changfeng; Du, Mingyi

    2016-06-01

    With the increasingly rapid growth of urbanization and climate change, urban rainfall monitoring as well as urban waterlogging has widely been paid attention. In the light of conventional siting selection methods do not take into consideration of geographic surroundings and spatial-temporal scale for the urban rain gauge site selection, this paper primarily aims at finding the appropriate siting selection rules and methods for rain gauge in urban area. Additionally, for optimization gauge location, a spatial decision support system (DSS) aided by geographical information system (GIS) has been developed. In terms of a series of criteria, the rain gauge optimal site-search problem can be addressed by a multicriteria decision analysis (MCDA). A series of spatial analytical techniques are required for MCDA to identify the prospective sites. With the platform of GIS, using spatial kernel density analysis can reflect the population density; GIS buffer analysis is used to optimize the location with the rain gauge signal transmission character. Experiment results show that the rules and the proposed method are proper for the rain gauge site selection in urban areas, which is significant for the siting selection of urban hydrological facilities and infrastructure, such as water gauge.

  4. 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.

  5. Switches in Genomic GC Content Drive Shifts of Optimal Codons under Sustained Selection on Synonymous Sites

    PubMed Central

    Sun, Yu; Tamarit, Daniel

    2017-01-01

    Abstract The major codon preference model suggests that codons read by tRNAs in high concentrations are preferentially utilized in highly expressed genes. However, the identity of the optimal codons differs between species although the forces driving such changes are poorly understood. We suggest that these questions can be tackled by placing codon usage studies in a phylogenetic framework and that bacterial genomes with extreme nucleotide composition biases provide informative model systems. Switches in the background substitution biases from GC to AT have occurred in Gardnerella vaginalis (GC = 32%), and from AT to GC in Lactobacillus delbrueckii (GC = 62%) and Lactobacillus fermentum (GC = 63%). We show that despite the large effects on codon usage patterns by these switches, all three species evolve under selection on synonymous sites. In G. vaginalis, the dramatic codon frequency changes coincide with shifts of optimal codons. In contrast, the optimal codons have not shifted in the two Lactobacillus genomes despite an increased fraction of GC-ending codons. We suggest that all three species are in different phases of an on-going shift of optimal codons, and attribute the difference to a stronger background substitution bias and/or longer time since the switch in G. vaginalis. We show that comparative and correlative methods for optimal codon identification yield conflicting results for genomes in flux and discuss possible reasons for the mispredictions. We conclude that switches in the direction of the background substitution biases can drive major shifts in codon preference patterns even under sustained selection on synonymous codon sites. PMID:27540085

  6. Optimization Under Uncertainty of Site-Specific Turbine Configurations

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

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

    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

  7. 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

  8. A scenario optimization model for dynamic reserve site selection

    Treesearch

    Stephanie A. Snyder; Robert G. Haight; Charles S. ReVelle

    2004-01-01

    Conservation planners are called upon to make choices and trade-offs about the preservation of natural areas for the protection of species in the face of development pressures. We addressed the problem of selecting sites for protection over time with the objective of maximizing species representation, with uncertainty about future site development, and with periodic...

  9. 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.

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

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

    Quick, Julian; Dykes, Katherine; Graf, Peter

    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 withmore » increasing risk aversion on the part of the designer.« less

  11. Study for the selection of optimal site in northeastern, Mexico for wind power generation using genetic algorithms.

    NASA Astrophysics Data System (ADS)

    Gonzalez, T.; Ruvalcaba, A.; Oliver, L.

    2016-12-01

    The electricity generation from renewable resources has acquired a leading role. Mexico particularrly it has great interest in renewable natural resources for power generation, especially wind energy. Therefore, the country is rapidly entering in the development of wind power generators sites. The development of a wind places as an energy project, does not have a standardized methodology. Techniques vary according to the developer to select the best place to install a wind turbine system. Generally to install the system the developers consider three key factors: 1) the characteristics of the wind, 2) the potential distribution of electricity and 3) transport access to the site. This paper presents a study with a different methodology which is carried out in two stages: the first at regional scale uses "space" and "natural" criteria in order to select a region based on its cartographic features such as politics and physiographic division, location of conservation natural areas, water bodies, urban criteria; and natural criteria such as the amount and direction of the wind, the type and land use, vegetation, topography and biodiversity of the site. The result of the application of these criteria, gives a first optimal selection area. The second part of the methodology includes criteria and variables on detail scale. The analysis of all data information collected will provide new parameters (decision variables) for the site. The overall analysis of the information, based in these criteria, indicates that the best location that the best location of the field would be the southern Coahuila and the central part of Nuevo Leon. The wind power site will contribute to the economy grow of important cities including Monterrey. Finally, computational model of genetic algorithm will be used as a tool to determine the best site selection depending on the parameters considered.

  12. Epicardial left ventricular lead placement for cardiac resynchronization therapy: optimal pace site selection with pressure-volume loops.

    PubMed

    Dekker, A L A J; Phelps, B; Dijkman, B; van der Nagel, T; van der Veen, F H; Geskes, G G; Maessen, J G

    2004-06-01

    Patients in heart failure with left bundle branch block benefit from cardiac resynchronization therapy. Usually the left ventricular pacing lead is placed by coronary sinus catheterization; however, this procedure is not always successful, and patients may be referred for surgical epicardial lead placement. The objective of this study was to develop a method to guide epicardial lead placement in cardiac resynchronization therapy. Eleven patients in heart failure who were eligible for cardiac resynchronization therapy were referred for surgery because of failed coronary sinus left ventricular lead implantation. Minithoracotomy or thoracoscopy was performed, and a temporary epicardial electrode was used for biventricular pacing at various sites on the left ventricle. Pressure-volume loops with the conductance catheter were used to select the best site for each individual patient. Relative to the baseline situation, biventricular pacing with an optimal left ventricular lead position significantly increased stroke volume (+39%, P =.01), maximal left ventricular pressure derivative (+20%, P =.02), ejection fraction (+30%, P =.007), and stroke work (+66%, P =.006) and reduced end-systolic volume (-6%, P =.04). In contrast, biventricular pacing at a suboptimal site did not significantly change left ventricular function and even worsened it in some cases. To optimize cardiac resynchronization therapy with epicardial leads, mapping to determine the best pace site is a prerequisite. Pressure-volume loops offer real-time guidance for targeting epicardial lead placement during minimal invasive surgery.

  13. Computational Prediction of Protein Epsilon Lysine Acetylation Sites Based on a Feature Selection Method.

    PubMed

    Gao, JianZhao; Tao, Xue-Wen; Zhao, Jia; Feng, Yuan-Ming; Cai, Yu-Dong; Zhang, Ning

    2017-01-01

    Lysine acetylation, as one type of post-translational modifications (PTM), plays key roles in cellular regulations and can be involved in a variety of human diseases. However, it is often high-cost and time-consuming to use traditional experimental approaches to identify the lysine acetylation sites. Therefore, effective computational methods should be developed to predict the acetylation sites. In this study, we developed a position-specific method for epsilon lysine acetylation site prediction. Sequences of acetylated proteins were retrieved from the UniProt database. Various kinds of features such as position specific scoring matrix (PSSM), amino acid factors (AAF), and disorders were incorporated. A feature selection method based on mRMR (Maximum Relevance Minimum Redundancy) and IFS (Incremental Feature Selection) was employed. Finally, 319 optimal features were selected from total 541 features. Using the 319 optimal features to encode peptides, a predictor was constructed based on dagging. As a result, an accuracy of 69.56% with MCC of 0.2792 was achieved. We analyzed the optimal features, which suggested some important factors determining the lysine acetylation sites. We developed a position-specific method for epsilon lysine acetylation site prediction. A set of optimal features was selected. Analysis of the optimal features provided insights into the mechanism of lysine acetylation sites, providing guidance of experimental validation. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  14. Analytic hierarchy process-based approach for selecting a Pareto-optimal solution of a multi-objective, multi-site supply-chain planning problem

    NASA Astrophysics Data System (ADS)

    Ayadi, Omar; Felfel, Houssem; Masmoudi, Faouzi

    2017-07-01

    The current manufacturing environment has changed from traditional single-plant to multi-site supply chain where multiple plants are serving customer demands. In this article, a tactical multi-objective, multi-period, multi-product, multi-site supply-chain planning problem is proposed. A corresponding optimization model aiming to simultaneously minimize the total cost, maximize product quality and maximize the customer satisfaction demand level is developed. The proposed solution approach yields to a front of Pareto-optimal solutions that represents the trade-offs among the different objectives. Subsequently, the analytic hierarchy process method is applied to select the best Pareto-optimal solution according to the preferences of the decision maker. The robustness of the solutions and the proposed approach are discussed based on a sensitivity analysis and an application to a real case from the textile and apparel industry.

  15. One- and two-objective approaches to an area-constrained habitat reserve site selection problem

    Treesearch

    Stephanie Snyder; Charles ReVelle; Robert Haight

    2004-01-01

    We compare several ways to model a habitat reserve site selection problem in which an upper bound on the total area of the selected sites is included. The models are cast as optimization coverage models drawn from the location science literature. Classic covering problems typically include a constraint on the number of sites that can be selected. If potential reserve...

  16. Optimized probability sampling of study sites to improve generalizability in a multisite intervention trial.

    PubMed

    Kraschnewski, Jennifer L; Keyserling, Thomas C; Bangdiwala, Shrikant I; Gizlice, Ziya; Garcia, Beverly A; Johnston, Larry F; Gustafson, Alison; Petrovic, Lindsay; Glasgow, Russell E; Samuel-Hodge, Carmen D

    2010-01-01

    Studies of type 2 translation, the adaption of evidence-based interventions to real-world settings, should include representative study sites and staff to improve external validity. Sites for such studies are, however, often selected by convenience sampling, which limits generalizability. We used an optimized probability sampling protocol to select an unbiased, representative sample of study sites to prepare for a randomized trial of a weight loss intervention. We invited North Carolina health departments within 200 miles of the research center to participate (N = 81). Of the 43 health departments that were eligible, 30 were interested in participating. To select a representative and feasible sample of 6 health departments that met inclusion criteria, we generated all combinations of 6 from the 30 health departments that were eligible and interested. From the subset of combinations that met inclusion criteria, we selected 1 at random. Of 593,775 possible combinations of 6 counties, 15,177 (3%) met inclusion criteria. Sites in the selected subset were similar to all eligible sites in terms of health department characteristics and county demographics. Optimized probability sampling improved generalizability by ensuring an unbiased and representative sample of study sites.

  17. Wind data for wind driven plant. [site selection for optimal performance

    NASA Technical Reports Server (NTRS)

    Stodhart, A. H.

    1973-01-01

    Simple, averaged wind velocity data provide information on energy availability, facilitate generator site selection and enable appropriate operating ranges to be established for windpowered plants. They also provide a basis for the prediction of extreme wind speeds.

  18. DHSpred: support-vector-machine-based human DNase I hypersensitive sites prediction using the optimal features selected by random forest.

    PubMed

    Manavalan, Balachandran; Shin, Tae Hwan; Lee, Gwang

    2018-01-05

    DNase I hypersensitive sites (DHSs) are genomic regions that provide important information regarding the presence of transcriptional regulatory elements and the state of chromatin. Therefore, identifying DHSs in uncharacterized DNA sequences is crucial for understanding their biological functions and mechanisms. Although many experimental methods have been proposed to identify DHSs, they have proven to be expensive for genome-wide application. Therefore, it is necessary to develop computational methods for DHS prediction. In this study, we proposed a support vector machine (SVM)-based method for predicting DHSs, called DHSpred (DNase I Hypersensitive Site predictor in human DNA sequences), which was trained with 174 optimal features. The optimal combination of features was identified from a large set that included nucleotide composition and di- and trinucleotide physicochemical properties, using a random forest algorithm. DHSpred achieved a Matthews correlation coefficient and accuracy of 0.660 and 0.871, respectively, which were 3% higher than those of control SVM predictors trained with non-optimized features, indicating the efficiency of the feature selection method. Furthermore, the performance of DHSpred was superior to that of state-of-the-art predictors. An online prediction server has been developed to assist the scientific community, and is freely available at: http://www.thegleelab.org/DHSpred.html.

  19. DHSpred: support-vector-machine-based human DNase I hypersensitive sites prediction using the optimal features selected by random forest

    PubMed Central

    Manavalan, Balachandran; Shin, Tae Hwan; Lee, Gwang

    2018-01-01

    DNase I hypersensitive sites (DHSs) are genomic regions that provide important information regarding the presence of transcriptional regulatory elements and the state of chromatin. Therefore, identifying DHSs in uncharacterized DNA sequences is crucial for understanding their biological functions and mechanisms. Although many experimental methods have been proposed to identify DHSs, they have proven to be expensive for genome-wide application. Therefore, it is necessary to develop computational methods for DHS prediction. In this study, we proposed a support vector machine (SVM)-based method for predicting DHSs, called DHSpred (DNase I Hypersensitive Site predictor in human DNA sequences), which was trained with 174 optimal features. The optimal combination of features was identified from a large set that included nucleotide composition and di- and trinucleotide physicochemical properties, using a random forest algorithm. DHSpred achieved a Matthews correlation coefficient and accuracy of 0.660 and 0.871, respectively, which were 3% higher than those of control SVM predictors trained with non-optimized features, indicating the efficiency of the feature selection method. Furthermore, the performance of DHSpred was superior to that of state-of-the-art predictors. An online prediction server has been developed to assist the scientific community, and is freely available at: http://www.thegleelab.org/DHSpred.html PMID:29416743

  20. Strong Purifying Selection at Synonymous Sites in D. melanogaster

    PubMed Central

    Lawrie, David S.; Messer, Philipp W.; Hershberg, Ruth; Petrov, Dmitri A.

    2013-01-01

    Synonymous sites are generally assumed to be subject to weak selective constraint. For this reason, they are often neglected as a possible source of important functional variation. We use site frequency spectra from deep population sequencing data to show that, contrary to this expectation, 22% of four-fold synonymous (4D) sites in Drosophila melanogaster evolve under very strong selective constraint while few, if any, appear to be under weak constraint. Linking polymorphism with divergence data, we further find that the fraction of synonymous sites exposed to strong purifying selection is higher for those positions that show slower evolution on the Drosophila phylogeny. The function underlying the inferred strong constraint appears to be separate from splicing enhancers, nucleosome positioning, and the translational optimization generating canonical codon bias. The fraction of synonymous sites under strong constraint within a gene correlates well with gene expression, particularly in the mid-late embryo, pupae, and adult developmental stages. Genes enriched in strongly constrained synonymous sites tend to be particularly functionally important and are often involved in key developmental pathways. Given that the observed widespread constraint acting on synonymous sites is likely not limited to Drosophila, the role of synonymous sites in genetic disease and adaptation should be reevaluated. PMID:23737754

  1. Field site selection

    NASA Technical Reports Server (NTRS)

    Schwarz, D. E.; Ellefsen, R. E.

    1981-01-01

    Several general guidelines should be kept in mind when considering the selection of field sites for teaching remote sensing fundamentals. Proximity and vantage point are two very practical considerations. Only through viewing a broad enough area to place the site in context can one make efficient use of a site. The effects of inclement weather when selecting sites should be considered. If field work is to be an effective tool to illustrate remote sensing principles, the following criteria are critical: (1) the site must represent the range of class interest; (2) the site must have a theme or add something no other site offers; (3) there should be intrasite variation within the theme; (4) ground resolution and spectral signature distinction should be illustrated; and (5) the sites should not be ordered sequentially.

  2. Computer-assisted selection of donor sites for autologous grafts

    NASA Astrophysics Data System (ADS)

    Krol, Zdzislaw; Zeilhofer, Hans-Florian U.; Sader, Robert; Hoffmann, Karl-Heinz; Gerhardt, Paul; Horch, Hans-Henning

    1997-05-01

    A new method is proposed for a precise planning of autologous bone grafts in cranio- and maxillofacial surgery. In patients with defects of the facial skeleton, autologous bone transplants can be harvested from various donor sites in the body. The preselection of a donor site depends i.a. on the morphological fit of the available bone mass and the shape of the part that is to be transplanted. A thorough planning and simulation of the surgical intervention based on 3D CT studies leads to a geometrical description and the volumetric characterization of the bone part to be resected and transplanted. Both, an optimal fit and a minimal lesion of the donor site are guidelines in this process. We use surface similarity and voxel similarity measures in order to select the optimal donor region for an individually designed transplant.

  3. 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

  4. 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

  5. Selectivity optimization in green chromatography by gradient stationary phase optimized selectivity liquid chromatography.

    PubMed

    Chen, Kai; Lynen, Frédéric; De Beer, Maarten; Hitzel, Laure; Ferguson, Paul; Hanna-Brown, Melissa; Sandra, Pat

    2010-11-12

    Stationary phase optimized selectivity liquid chromatography (SOSLC) is a promising technique to optimize the selectivity of a given separation by using a combination of different stationary phases. Previous work has shown that SOSLC offers excellent possibilities for method development, especially after the recent modification towards linear gradient SOSLC. The present work is aimed at developing and extending the SOSLC approach towards selectivity optimization and method development for green chromatography. Contrary to current LC practices, a green mobile phase (water/ethanol/formic acid) is hereby preselected and the composition of the stationary phase is optimized under a given gradient profile to obtain baseline resolution of all target solutes in the shortest possible analysis time. With the algorithm adapted to the high viscosity property of ethanol, the principle is illustrated with a fast, full baseline resolution for a randomly selected mixture composed of sulphonamides, xanthine alkaloids and steroids. Copyright © 2010 Elsevier B.V. All rights reserved.

  6. 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

  7. Identification of potential sites for deep-ocean waste isolation with a geographic site-selection model

    NASA Astrophysics Data System (ADS)

    Fleischer, Peter; Bowles, Frederick A.; Richardson, Michael D.

    1998-05-01

    Identification of optimal sites for the isolation of waste on the abyssal seafloor was performed with two approaches: by the traditional method of map overlays of relevant attributes, and by a specially developed, automated Site-Selection Model (SSM). Five initial, Surrogate Sites, identified with the map-overlay approach, were then compared with the more rigorously produced scores from the SSM. The SSM, a process for optimization of site locations, accepts subjective, expert-based judgments and transforms them into a quantitative, reproducible, and documented product. The SSM is adaptable to any siting scenario. Forty-one factors relevant to the isolation scenario, including 21 weightable factors having a total of 123 scorable categories, have been entered into the SSM. Factors are grouped under project definition, unique environments, anthropogenic, geologic, biologic, weather, oceanographic and distance criteria. The factor scores are linked to a georeferenced database array of all factors, corresponding to 1°×1° latitude-longitude squares. The SSM includes a total of 2241 one-degree squares within 1000 n.m. of the U.S. coasts, including the western North Atlantic, the Gulf of Mexico, and the eastern North Pacific. Under a carefully weighted and scored scenario of isolation, the most favorable sites identified with the SSM are on the Hatteras and Nares Abyssal Plains in the Atlantic. High-scoring sites are also located in the Pacific abyssal hills province between the Murray and Molokai Fracture Zones. Acceptable 1° squares in the Gulf of Mexico are few and of lower quality, with the optimum location on the northern Sigsbee Abyssal Plain. Two of the five Surrogate Site locations, on the Hatteras and Sigsbee Abyssal Plains, correspond to the best SSM sites in each ocean area. Two Pacific and a second Atlantic Surrogate Site are located in low-scoring regions or excluded by the SSM. Site-selection results from the SSM, although robust, are an initial attempt

  8. Self-extinction through optimizing selection.

    PubMed

    Parvinen, Kalle; Dieckmann, Ulf

    2013-09-21

    Evolutionary suicide is a process in which selection drives a viable population to extinction. So far, such selection-driven self-extinction has been demonstrated in models with frequency-dependent selection. This is not surprising, since frequency-dependent selection can disconnect individual-level and population-level interests through environmental feedback. Hence it can lead to situations akin to the tragedy of the commons, with adaptations that serve the selfish interests of individuals ultimately ruining a population. For frequency-dependent selection to play such a role, it must not be optimizing. Together, all published studies of evolutionary suicide have created the impression that evolutionary suicide is not possible with optimizing selection. Here we disprove this misconception by presenting and analyzing an example in which optimizing selection causes self-extinction. We then take this line of argument one step further by showing, in a further example, that selection-driven self-extinction can occur even under frequency-independent selection. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. 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…

  10. 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.

  11. School Site Selection and Approval Guide.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Div. of School Facilities Planning.

    This guide is designed to assist school districts in selecting school sites that provide both a safe and supportive environment for the instructional program and the learning process, and gain state approval for the selected sites. The guide includes a set of selection criteria that have proven helpful to site selection teams, information about…

  12. Computer-based planning of optimal donor sites for autologous osseous grafts

    NASA Astrophysics Data System (ADS)

    Krol, Zdzislaw; Chlebiej, Michal; Zerfass, Peter; Zeilhofer, Hans-Florian U.; Sader, Robert; Mikolajczak, Pawel; Keeve, Erwin

    2002-05-01

    Bone graft surgery is often necessary for reconstruction of craniofacial defects after trauma, tumor, infection or congenital malformation. In this operative technique the removed or missing bone segment is filled with a bone graft. The mainstay of the craniofacial reconstruction rests with the replacement of the defected bone by autogeneous bone grafts. To achieve sufficient incorporation of the autograft into the host bone, precise planning and simulation of the surgical intervention is required. The major problem is to determine as accurately as possible the donor site where the graft should be dissected from and to define the shape of the desired transplant. A computer-aided method for semi-automatic selection of optimal donor sites for autografts in craniofacial reconstructive surgery has been developed. The non-automatic step of graft design and constraint setting is followed by a fully automatic procedure to find the best fitting position. In extension to preceding work, a new optimization approach based on the Levenberg-Marquardt method has been implemented and embedded into our computer-based surgical planning system. This new technique enables, once the pre-processing step has been performed, selection of the optimal donor site in time less than one minute. The method has been applied during surgery planning step in more than 20 cases. The postoperative observations have shown that functional results, such as speech and chewing ability as well as restoration of bony continuity were clearly better compared to conventionally planned operations. Moreover, in most cases the duration of the surgical interventions has been distinctly reduced.

  13. Selecting optimal monitoring site locations for peak ambient particulate material concentrations using the MM5-CAMx4 numerical modelling system.

    PubMed

    Sturman, Andrew; Titov, Mikhail; Zawar-Reza, Peyman

    2011-01-15

    Installation of temporary or long term monitoring sites is expensive, so it is important to rationally identify potential locations that will achieve the requirements of regional air quality management strategies. A simple, but effective, numerical approach to selecting ambient particulate matter (PM) monitoring site locations has therefore been developed using the MM5-CAMx4 air pollution dispersion modelling system. A new method, 'site efficiency,' was developed to assess the ability of any monitoring site to provide peak ambient air pollution concentrations that are representative of the urban area. 'Site efficiency' varies from 0 to 100%, with the latter representing the most representative site location for monitoring peak PM concentrations. Four heavy pollution episodes in Christchurch (New Zealand) during winter 2005, representing 4 different aerosol dispersion patterns, were used to develop and test this site assessment technique. Evaluation of the efficiency of monitoring sites was undertaken for night and morning aerosol peaks for 4 different particulate material (PM) spatial patterns. The results demonstrate that the existing long term monitoring site at Coles Place is quite well located, with a site efficiency value of 57.8%. A temporary ambient PM monitoring site (operating during winter 2006) showed a lower ability to capture night and morning peak aerosol concentrations. Evaluation of multiple site locations used during an extensive field campaign in Christchurch (New Zealand) in 2000 indicated that the maximum efficiency achieved by any site in the city would be 60-65%, while the efficiency of a virtual background site is calculated to be about 7%. This method of assessing the appropriateness of any potential monitoring site can be used to optimize monitoring site locations for any air pollution measurement programme. Copyright © 2010 Elsevier B.V. All rights reserved.

  14. Selective robust optimization: A new intensity-modulated proton therapy optimization strategy

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

    Li, Yupeng; Niemela, Perttu; Siljamaki, Sami

    2015-08-15

    Purpose: To develop a new robust optimization strategy for intensity-modulated proton therapy as an important step in translating robust proton treatment planning from research to clinical applications. Methods: In selective robust optimization, a worst-case-based robust optimization algorithm is extended, and terms of the objective function are selectively computed from either the worst-case dose or the nominal dose. Two lung cancer cases and one head and neck cancer case were used to demonstrate the practical significance of the proposed robust planning strategy. The lung cancer cases had minimal tumor motion less than 5 mm, and, for the demonstration of the methodology,more » are assumed to be static. Results: Selective robust optimization achieved robust clinical target volume (CTV) coverage and at the same time increased nominal planning target volume coverage to 95.8%, compared to the 84.6% coverage achieved with CTV-based robust optimization in one of the lung cases. In the other lung case, the maximum dose in selective robust optimization was lowered from a dose of 131.3% in the CTV-based robust optimization to 113.6%. Selective robust optimization provided robust CTV coverage in the head and neck case, and at the same time improved controls over isodose distribution so that clinical requirements may be readily met. Conclusions: Selective robust optimization may provide the flexibility and capability necessary for meeting various clinical requirements in addition to achieving the required plan robustness in practical proton treatment planning settings.« less

  15. 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.

  16. Use of strategic environmental assessment in the site selection process for a radioactive waste disposal facility in Slovenia.

    PubMed

    Dermol, Urška; Kontić, Branko

    2011-01-01

    The benefits of strategic environmental considerations in the process of siting a repository for low- and intermediate-level radioactive waste (LILW) are presented. The benefits have been explored by analyzing differences between the two site selection processes. One is a so-called official site selection process, which is implemented by the Agency for radwaste management (ARAO); the other is an optimization process suggested by experts working in the area of environmental impact assessment (EIA) and land-use (spatial) planning. The criteria on which the comparison of the results of the two site selection processes has been based are spatial organization, environmental impact, safety in terms of potential exposure of the population to radioactivity released from the repository, and feasibility of the repository from the technical, financial/economic and social point of view (the latter relates to consent by the local community for siting the repository). The site selection processes have been compared with the support of the decision expert system named DEX. The results of the comparison indicate that the sites selected by ARAO meet fewer suitability criteria than those identified by applying strategic environmental considerations in the framework of the optimization process. This result stands when taking into account spatial, environmental, safety and technical feasibility points of view. Acceptability of a site by a local community could not have been tested, since the formal site selection process has not yet been concluded; this remains as an uncertain and open point of the comparison. Copyright © 2010 Elsevier Ltd. All rights reserved.

  17. 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.

  18. Extensively Parameterized Mutation-Selection Models Reliably Capture Site-Specific Selective Constraint.

    PubMed

    Spielman, Stephanie J; Wilke, Claus O

    2016-11-01

    The mutation-selection model of coding sequence evolution has received renewed attention for its use in estimating site-specific amino acid propensities and selection coefficient distributions. Two computationally tractable mutation-selection inference frameworks have been introduced: One framework employs a fixed-effects, highly parameterized maximum likelihood approach, whereas the other employs a random-effects Bayesian Dirichlet Process approach. While both implementations follow the same model, they appear to make distinct predictions about the distribution of selection coefficients. The fixed-effects framework estimates a large proportion of highly deleterious substitutions, whereas the random-effects framework estimates that all substitutions are either nearly neutral or weakly deleterious. It remains unknown, however, how accurately each method infers evolutionary constraints at individual sites. Indeed, selection coefficient distributions pool all site-specific inferences, thereby obscuring a precise assessment of site-specific estimates. Therefore, in this study, we use a simulation-based strategy to determine how accurately each approach recapitulates the selective constraint at individual sites. We find that the fixed-effects approach, despite its extensive parameterization, consistently and accurately estimates site-specific evolutionary constraint. By contrast, the random-effects Bayesian approach systematically underestimates the strength of natural selection, particularly for slowly evolving sites. We also find that, despite the strong differences between their inferred selection coefficient distributions, the fixed- and random-effects approaches yield surprisingly similar inferences of site-specific selective constraint. We conclude that the fixed-effects mutation-selection framework provides the more reliable software platform for model application and future development. © The Author 2016. Published by Oxford University Press on behalf of the

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

    USGS Publications Warehouse

    McCarthy, Kyle P.; DeStefano, Stephen

    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, R2 = 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.

  20. An ArcGIS decision support tool for artificial reefs site selection (ArcGIS ARSS)

    NASA Astrophysics Data System (ADS)

    Stylianou, Stavros; Zodiatis, George

    2017-04-01

    Although the use and benefits of artificial reefs, both socio-economic and environmental, have been recognized with research and national development programmes worldwide their development is rarely subjected to a rigorous site selection process and the majority of the projects use the traditional (non-GIS) approach, based on trial and error mode. Recent studies have shown that the use of Geographic Information Systems, unlike to traditional methods, for the identification of suitable areas for artificial reefs siting seems to offer a number of distinct advantages minimizing possible errors, time and cost. A decision support tool (DSS) has been developed based on the existing knowledge, the multi-criteria decision analysis techniques and the GIS approach used in previous studies in order to help the stakeholders to identify the optimal locations for artificial reefs deployment on the basis of the physical, biological, oceanographic and socio-economic features of the sites. The tool provides to the users the ability to produce a final report with the results and suitability maps. The ArcGIS ARSS support tool runs within the existing ArcMap 10.2.x environment and for the development the VB .NET high level programming language has been used along with ArcObjects 10.2.x. Two local-scale case studies were conducted in order to test the application of the tool focusing on artificial reef siting. The results obtained from the case studies have shown that the tool can be successfully integrated within the site selection process in order to select objectively the optimal site for artificial reefs deployment.

  1. 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.

  2. 32 CFR 644.22 - Site selection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Site selection. 644.22 Section 644.22 National... HANDBOOK Project Planning Military (army and Air Force) and Other Federal Agencies § 644.22 Site selection... selection will be the primary responsibility of the using service. A representative of the appropriate...

  3. Artificial Intelligence Support for Landing Site Selection on Mars

    NASA Astrophysics Data System (ADS)

    Rongier, G.; Pankratius, V.

    2017-12-01

    Mars is a key target for planetary exploration; a better understanding of its evolution and habitability requires roving in situ. Landing site selection is becoming more challenging for scientists as new instruments generate higher data volumes. The involved engineering and scientific constraints make site selection and the anticipation of possible onsite actions into a complex optimization problem: there may be multiple acceptable solutions depending on various goals and assumptions. Solutions must also account for missing data, errors, and potential biases. To address these problems, we propose an AI-informed decision support system that allows scientists, mission designers, engineers, and committees to explore alternative site selection choices based on data. In particular, we demonstrate first results of an exploratory case study using fuzzy logic and a simulation of a rover's mobility map based on the fast marching algorithm. Our system computes favorability maps of the entire planet to facilitate landing site selection and allows a definition of different configurations for rovers, science target priorities, landing ellipses, and other constraints. For a rover similar to NASA's Mars 2020 rover, we present results in form of a site favorability map as well as four derived exploration scenarios that depend on different prioritized scientific targets, all visualizing inherent tradeoffs. Our method uses the NASA PDS Geosciences Node and the NASA/ICA Integrated Database of Planetary Features. Under common assumptions, the data products reveal Eastern Margaritifer Terra and Meridiani Planum to be the most favorable sites due to a high concentration of scientific targets and a flat, easily navigable surface. Our method also allows mission designers to investigate which constraints have the highest impact on the mission exploration potential and to change parameter ranges. Increasing the elevation limit for landing, for example, provides access to many additional

  4. Optimal Item Selection with Credentialing Examinations.

    ERIC Educational Resources Information Center

    Hambleton, Ronald K.; And Others

    The study compared two promising item response theory (IRT) item-selection methods, optimal and content-optimal, with two non-IRT item selection methods, random and classical, for use in fixed-length certification exams. The four methods were used to construct 20-item exams from a pool of approximately 250 items taken from a 1985 certification…

  5. Space-planning and structural solutions of low-rise buildings: Optimal selection methods

    NASA Astrophysics Data System (ADS)

    Gusakova, Natalya; Minaev, Nikolay; Filushina, Kristina; Dobrynina, Olga; Gusakov, Alexander

    2017-11-01

    The present study is devoted to elaboration of methodology used to select appropriately the space-planning and structural solutions in low-rise buildings. Objective of the study is working out the system of criteria influencing the selection of space-planning and structural solutions which are most suitable for low-rise buildings and structures. Application of the defined criteria in practice aim to enhance the efficiency of capital investments, energy and resource saving, create comfortable conditions for the population considering climatic zoning of the construction site. Developments of the project can be applied while implementing investment-construction projects of low-rise housing at different kinds of territories based on the local building materials. The system of criteria influencing the optimal selection of space-planning and structural solutions of low-rise buildings has been developed. Methodological basis has been also elaborated to assess optimal selection of space-planning and structural solutions of low-rise buildings satisfying the requirements of energy-efficiency, comfort and safety, and economical efficiency. Elaborated methodology enables to intensify the processes of low-rise construction development for different types of territories taking into account climatic zoning of the construction site. Stimulation of low-rise construction processes should be based on the system of approaches which are scientifically justified; thus it allows enhancing energy efficiency, comfort, safety and economical effectiveness of low-rise buildings.

  6. The School Site Planner. Land for Learning. Site Selection, Site Planning, Playgrounds, Recreation, and Athletic Fields.

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Public Instruction, Raleigh. Div. of School Support.

    The selection and planning of sites for school facilities can be critical and difficult due to the varied and complex demands schools must satisfy. This publication addresses the many factors that need consideration during the process of site selection, planning, development, and use. The report examines not only the site selection and planning…

  7. 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

  8. Selective Optimization

    DTIC Science & Technology

    2015-07-06

    NUMBER 5b. GRANT NUMBER AFOSR FA9550-12-1-0154 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Shabbir Ahmed and Santanu S. Dey 5d. PROJECT NUMBER 5e. TASK...standard mixed-integer programming (MIP) formulations of selective optimization problems. While such formulations can be attacked by commercial...F33615-86-C-5169. 5b. GRANT NUMBER. Enter all grant numbers as they appear in the report, e.g. AFOSR-82-1234. 5c. PROGRAM ELEMENT NUMBER. Enter

  9. 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.

  10. Optimel: Software for selecting the optimal method

    NASA Astrophysics Data System (ADS)

    Popova, Olga; Popov, Boris; Romanov, Dmitry; Evseeva, Marina

    Optimel: software for selecting the optimal method automates the process of selecting a solution method from the optimization methods domain. Optimel features practical novelty. It saves time and money when conducting exploratory studies if its objective is to select the most appropriate method for solving an optimization problem. Optimel features theoretical novelty because for obtaining the domain a new method of knowledge structuring was used. In the Optimel domain, extended quantity of methods and their properties are used, which allows identifying the level of scientific studies, enhancing the user's expertise level, expand the prospects the user faces and opening up new research objectives. Optimel can be used both in scientific research institutes and in educational institutions.

  11. 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

  12. Ensemble of surrogates-based optimization for identifying an optimal surfactant-enhanced aquifer remediation strategy at heterogeneous DNAPL-contaminated sites

    NASA Astrophysics Data System (ADS)

    Jiang, Xue; Lu, Wenxi; Hou, Zeyu; Zhao, Haiqing; Na, Jin

    2015-11-01

    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.

  13. 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.

  14. Geospatial Analytics in Retail Site Selection and Sales Prediction.

    PubMed

    Ting, Choo-Yee; Ho, Chiung Ching; Yee, Hui Jia; Matsah, Wan Razali

    2018-03-01

    Studies have shown that certain features from geography, demography, trade area, and environment can play a vital role in retail site selection, largely due to the impact they asserted on retail performance. Although the relevant features could be elicited by domain experts, determining the optimal feature set can be intractable and labor-intensive exercise. The challenges center around (1) how to determine features that are important to a particular retail business and (2) how to estimate retail sales performance given a new location? The challenges become apparent when the features vary across time. In this light, this study proposed a nonintervening approach by employing feature selection algorithms and subsequently sales prediction through similarity-based methods. The results of prediction were validated by domain experts. In this study, data sets from different sources were transformed and aggregated before an analytics data set that is ready for analysis purpose could be obtained. The data sets included data about feature location, population count, property type, education status, and monthly sales from 96 branches of a telecommunication company in Malaysia. The finding suggested that (1) optimal retail performance can only be achieved through fulfillment of specific location features together with the surrounding trade area characteristics and (2) similarity-based method can provide solution to retail sales prediction.

  15. Prioritizing conservation activities using reserve site selection methods and population viability analysis.

    PubMed

    Newbold, Stephen C; Siikamäki, Juha

    2009-10-01

    In recent years a large literature on reserve site selection (RSS) has developed at the interface between ecology, operations research, and environmental economics. Reserve site selection models use numerical optimization techniques to select sites for a network of nature reserves for protecting biodiversity. In this paper, we develop a population viability analysis (PVA) model for salmon and incorporate it into an RSS framework for prioritizing conservation activities in upstream watersheds. We use spawner return data for three closely related salmon stocks in the upper Columbia River basin and estimates of the economic costs of watershed protection from NOAA to illustrate the framework. We compare the relative cost-effectiveness of five alternative watershed prioritization methods, based on various combinations of biological and economic information. Prioritization based on biological benefit-economic cost comparisons and accounting for spatial interdependencies among watersheds substantially outperforms other more heuristic methods. When using this best-performing prioritization method, spending 10% of the cost of protecting all upstream watersheds yields 79% of the biological benefits (increase in stock persistence) from protecting all watersheds, compared to between 20% and 64% for the alternative methods. We also find that prioritization based on either costs or benefits alone can lead to severe reductions in cost-effectiveness.

  16. Model of the best-of-N nest-site selection process in honeybees

    NASA Astrophysics Data System (ADS)

    Reina, Andreagiovanni; Marshall, James A. R.; Trianni, Vito; Bose, Thomas

    2017-05-01

    The ability of a honeybee swarm to select the best nest site plays a fundamental role in determining the future colony's fitness. To date, the nest-site selection process has mostly been modeled and theoretically analyzed for the case of binary decisions. However, when the number of alternative nests is larger than two, the decision-process dynamics qualitatively change. In this work, we extend previous analyses of a value-sensitive decision-making mechanism to a decision process among N nests. First, we present the decision-making dynamics in the symmetric case of N equal-quality nests. Then, we generalize our findings to a best-of-N decision scenario with one superior nest and N -1 inferior nests, previously studied empirically in bees and ants. Whereas previous binary models highlighted the crucial role of inhibitory stop-signaling, the key parameter in our new analysis is the relative time invested by swarm members in individual discovery and in signaling behaviors. Our new analysis reveals conflicting pressures on this ratio in symmetric and best-of-N decisions, which could be solved through a time-dependent signaling strategy. Additionally, our analysis suggests how ecological factors determining the density of suitable nest sites may have led to selective pressures for an optimal stable signaling ratio.

  17. Model of the best-of-N nest-site selection process in honeybees.

    PubMed

    Reina, Andreagiovanni; Marshall, James A R; Trianni, Vito; Bose, Thomas

    2017-05-01

    The ability of a honeybee swarm to select the best nest site plays a fundamental role in determining the future colony's fitness. To date, the nest-site selection process has mostly been modeled and theoretically analyzed for the case of binary decisions. However, when the number of alternative nests is larger than two, the decision-process dynamics qualitatively change. In this work, we extend previous analyses of a value-sensitive decision-making mechanism to a decision process among N nests. First, we present the decision-making dynamics in the symmetric case of N equal-quality nests. Then, we generalize our findings to a best-of-N decision scenario with one superior nest and N-1 inferior nests, previously studied empirically in bees and ants. Whereas previous binary models highlighted the crucial role of inhibitory stop-signaling, the key parameter in our new analysis is the relative time invested by swarm members in individual discovery and in signaling behaviors. Our new analysis reveals conflicting pressures on this ratio in symmetric and best-of-N decisions, which could be solved through a time-dependent signaling strategy. Additionally, our analysis suggests how ecological factors determining the density of suitable nest sites may have led to selective pressures for an optimal stable signaling ratio.

  18. Using Temporal Modulation Sensitivity to Select Stimulation Sites for Processor MAPs in Cochlear Implant Listeners

    PubMed Central

    Garadat, Soha N.; Zwolan, Teresa A.; Pfingst, Bryan E.

    2013-01-01

    Previous studies in our laboratory showed that temporal acuity as assessed by modulation detection thresholds (MDTs) varied across activation sites and that this site-to-site variability was subject specific. Using two 10-channel MAPs, the previous experiments showed that processor MAPs that had better across-site mean (ASM) MDTs yielded better speech recognition than MAPs with poorer ASM MDTs tested in the same subject. The current study extends our earlier work on developing more optimal fitting strategies to test the feasibility of using a site-selection approach in the clinical domain. This study examined the hypothesis that revising the clinical speech processor MAP for cochlear implant (CI) recipients by turning off selected sites that have poorer temporal acuity and reallocating frequencies to the remaining electrodes would lead to improved speech recognition. Twelve CI recipients participated in the experiments. We found that site selection procedure based on MDTs in the presence of a masker resulted in improved performance on consonant recognition and recognition of sentences in noise. In contrast, vowel recognition was poorer with the experimental MAP than with the clinical MAP, possibly due to reduced spectral resolution when sites were removed from the experimental MAP. Overall, these results suggest a promising path for improving recipient outcomes using personalized processor-fitting strategies based on a psychophysical measure of temporal acuity. PMID:23881208

  19. 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.

  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... selection. ...

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

    PubMed

    Ekmekçioğlu, Mehmet; Kaya, Tolga; Kahraman, Cengiz

    2010-01-01

    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. 2010 Elsevier Ltd. All rights reserved.

  2. 40 CFR 228.6 - Specific criteria for site selection.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Specific criteria for site selection... selection. (a) In the selection of disposal sites, in addition to other necessary or appropriate factors...) Existence at or in close proximity to the site of any significant natural or cultural features of historical...

  3. Mining for helium: Site selection and evaluation

    NASA Technical Reports Server (NTRS)

    Cameron, Eugene N.

    1988-01-01

    Part of the University of Wisconsin study of the feasibility of recovering He-3 from the moon is selection and evaluation of potential mining sites. Selection and evaluation are based primarily on salient findings by investigators: (1) Regoliths from areas underlain by highland materials contain less than 20 wppm He; (2) Regoliths of certain maria or parts of maria also contain less than 20 wppm He, but mare regoliths at the Apollo 11 and 17 sites contain 25 to 49 wppm He; (3) The helium content of a regolith is a function of its composition; and (4) Helium is concentrated in the -50 micron size fractions of regoliths. In site selection, the concern is with the compositions of lunar regoliths, in particular with their titanium contents. It is widely accepted that compositions of mare regoliths are controlled by the nature of the underlying basalts from which the regoliths are largely derived. The distribution and extent of the three groups of basalts and the regoliths derived from them are the first basis for site selection and evaluation. Other considerations are briefly discussed.

  4. Selective Enrichment and Direct Analysis of Protein S-Palmitoylation Sites.

    PubMed

    Thinon, Emmanuelle; Fernandez, Joseph P; Molina, Henrik; Hang, Howard C

    2018-05-04

    S-Fatty-acylation is the covalent attachment of long chain fatty acids, predominately palmitate (C16:0, S-palmitoylation), to cysteine (Cys) residues via a thioester linkage on proteins. This post-translational and reversible lipid modification regulates protein function and localization in eukaryotes and is important in mammalian physiology and human diseases. While chemical labeling methods have improved the detection and enrichment of S-fatty-acylated proteins, mapping sites of modification and characterizing the endogenously attached fatty acids are still challenging. Here, we describe the integration and optimization of fatty acid chemical reporter labeling with hydroxylamine-mediated enrichment of S-fatty-acylated proteins and direct tagging of modified Cys residues to selectively map lipid modification sites. This afforded improved enrichment and direct identification of many protein S-fatty-acylation sites compared to previously described methods. Notably, we directly identified the S-fatty-acylation sites of IFITM3, an important interferon-stimulated inhibitor of virus entry, and we further demonstrated that the highly conserved Cys residues are primarily modified by palmitic acid. The methods described here should facilitate the direct analysis of protein S-fatty-acylation sites and their endogenously attached fatty acids in diverse cell types and activation states important for mammalian physiology and diseases.

  5. 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.

  6. Optimizing Travel Time to Outpatient Interventional Radiology Procedures in a Multi-Site Hospital System Using a Google Maps Application.

    PubMed

    Mandel, Jacob E; Morel-Ovalle, Louis; Boas, Franz E; Ziv, Etay; Yarmohammadi, Hooman; Deipolyi, Amy; Mohabir, Heeralall R; Erinjeri, Joseph P

    2018-02-20

    The purpose of this study is to determine whether a custom Google Maps application can optimize site selection when scheduling outpatient interventional radiology (IR) procedures within a multi-site hospital system. The Google Maps for Business Application Programming Interface (API) was used to develop an internal web application that uses real-time traffic data to determine estimated travel time (ETT; minutes) and estimated travel distance (ETD; miles) from a patient's home to each a nearby IR facility in our hospital system. Hypothetical patient home addresses based on the 33 cities comprising our institution's catchment area were used to determine the optimal IR site for hypothetical patients traveling from each city based on real-time traffic conditions. For 10/33 (30%) cities, there was discordance between the optimal IR site based on ETT and the optimal IR site based on ETD at non-rush hour time or rush hour time. By choosing to travel to an IR site based on ETT rather than ETD, patients from discordant cities were predicted to save an average of 7.29 min during non-rush hour (p = 0.03), and 28.80 min during rush hour (p < 0.001). Using a custom Google Maps application to schedule outpatients for IR procedures can effectively reduce patient travel time when more than one location providing IR procedures is available within the same hospital system.

  7. Combinatorial Optimization in Project Selection Using Genetic Algorithm

    NASA Astrophysics Data System (ADS)

    Dewi, Sari; Sawaluddin

    2018-01-01

    This paper discusses the problem of project selection in the presence of two objective functions that maximize profit and minimize cost and the existence of some limitations is limited resources availability and time available so that there is need allocation of resources in each project. These resources are human resources, machine resources, raw material resources. This is treated as a consideration to not exceed the budget that has been determined. So that can be formulated mathematics for objective function (multi-objective) with boundaries that fulfilled. To assist the project selection process, a multi-objective combinatorial optimization approach is used to obtain an optimal solution for the selection of the right project. It then described a multi-objective method of genetic algorithm as one method of multi-objective combinatorial optimization approach to simplify the project selection process in a large scope.

  8. Site Selection for the Disposal of LLW in Taiwan

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

    Chuang, W.S.; Chi, L.M.; Tien, N.C.

    2006-07-01

    This paper presents the implementation status of the low-level radioactive waste (LLW) disposal program in Taiwan, including the disposal facility regulations, status of waste management, final disposal program, licensing procedures, waste acceptance criteria, site selection criteria and processes and preliminary disposal concepts. The first phase of site selection for low-level radioactive waste final disposal in Taiwan was implemented between 1992 and 2002. The site selection process adopted a Geographic Information System (GIS), Hierarchical Analysis System, Expert Evaluation System, and site reconnaissance. An incentive program for voluntary sites was also initiated. After a series of evaluations and discussion of 30 potentialmore » candidate sites, including 8 recommended sites, 5 qualified voluntary townships, and several remote uninhabited small islets, Hsiao-chiou islet was selected as the first priority candidate site in February 1998. The geological investigation work in Hsiao-chiou was conducted from March 1999 through October 2000. An Environmental Impact Statement Report (EIS) and the Investment Feasibility Study Report (IFS) were submitted to the Environmental Protection Agency (EPA) in November 2000 and to the Ministry of Economic Affairs (MOEA) in June 2001, respectively. Unfortunately, the site investigation was discontinued in 2002 due to political and public acceptance consideration. After years of planning, the second phase of the site selection process was launched in August 2004 and will be conducted through 2008. It is planned that a repository will be constructed in early 2009 and start to operate in 2014. The site selection process for the second phase is based on the earlier work and four potential candidate sites were selected for evaluation until 2005. A near surface disposal concept is proposed for a site located in the Taiwan strait, and cavern disposal concepts are proposed for three other sites located on the main island. This

  9. 40 CFR 240.202 - Site selection.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 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 Site...

  10. Plasticity of the Binding Site of Renin: Optimized Selection of Protein Structures for Ensemble Docking.

    PubMed

    Strecker, Claas; Meyer, Bernd

    2018-05-29

    Protein flexibility poses a major challenge to docking of potential ligands in that the binding site can adopt different shapes. Docking algorithms usually keep the protein rigid and only allow the ligand to be treated as flexible. However, a wrong assessment of the shape of the binding pocket can prevent a ligand from adapting a correct pose. Ensemble docking is a simple yet promising method to solve this problem: Ligands are docked into multiple structures, and the results are subsequently merged. Selection of protein structures is a significant factor for this approach. In this work we perform a comprehensive and comparative study evaluating the impact of structure selection on ensemble docking. We perform ensemble docking with several crystal structures and with structures derived from molecular dynamics simulations of renin, an attractive target for antihypertensive drugs. Here, 500 ns of MD simulations revealed binding site shapes not found in any available crystal structure. We evaluate the importance of structure selection for ensemble docking by comparing binding pose prediction, ability to rank actives above nonactives (screening utility), and scoring accuracy. As a result, for ensemble definition k-means clustering appears to be better suited than hierarchical clustering with average linkage. The best performing ensemble consists of four crystal structures and is able to reproduce the native ligand poses better than any individual crystal structure. Moreover this ensemble outperforms 88% of all individual crystal structures in terms of screening utility as well as scoring accuracy. Similarly, ensembles of MD-derived structures perform on average better than 75% of any individual crystal structure in terms of scoring accuracy at all inspected ensembles sizes.

  11. Development of a Method for Selecting Optimum Sites for the Automatic Mountain Meteorology Observation Station (AMOS) to Improve Predictability of Forest Fires in Inaccessible Area

    NASA Astrophysics Data System (ADS)

    Yoon, S.; Won, M.; Jang, K.; Lim, J.

    2016-12-01

    As there has been a recent increase in the case of forest fires in North Korea descending southward through the De-Militarized Zone (DMZ), ensuring proper response to such events has been a challenge. Therefore, in order to respond and manage these forest fires appropriately, an improvement in the forest fire predictability through integration of mountain weather information observed at the most optimal site is necessary. This study is a proactive case in which a spatial analysis and an on-site assessment method were developed for selecting an optimum site for a mountain weather observation in national forest. For spatial analysis, the class 1 and 2 forest fire danger areas for the past 10 years, accessibility maximum 100m, Automatic Weather Station (AWS) redundancy within 2.5km, and mountain terrains higher than 200m were analyzed. A final overlay analysis was performed to select the candidates for the field assessment. The sites selected through spatial analysis were quantitatively evaluated based on the optimal meteorological environment, forest and hiking trail accessibility, AWS redundancy, and supply of wireless communication and solar powered electricity. The sites with total score of 70 and higher were accepted as adequate. At the final selected sites, an AMOS was established, and integration of mountain and Korea Meteorological Administration (KMA) weather data improved the forest fire predictability in South Korea by 10%. Given these study results, we expect that establishing an automatic mountain meteorology observation station at the optimal sites in inaccessible area and integrating mountain weather data will improve the predictability of forest fires.

  12. 15 CFR 921.11 - Site selection and feasibility.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... MANAGEMENT NATIONAL ESTUARINE RESEARCH RESERVE SYSTEM REGULATIONS Site Selection, Post Site Selection and... National Estuarine Research Reserve System. NOAA will give priority consideration to proposals to establish... of flora and fauna, and capacity to attract a broad range of research and educational interests. The...

  13. 15 CFR 921.11 - Site selection and feasibility.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... MANAGEMENT NATIONAL ESTUARINE RESEARCH RESERVE SYSTEM REGULATIONS Site Selection, Post Site Selection and... National Estuarine Research Reserve System. NOAA will give priority consideration to proposals to establish... of flora and fauna, and capacity to attract a broad range of research and educational interests. The...

  14. 15 CFR 921.11 - Site selection and feasibility.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... MANAGEMENT NATIONAL ESTUARINE RESEARCH RESERVE SYSTEM REGULATIONS Site Selection, Post Site Selection and... National Estuarine Research Reserve System. NOAA will give priority consideration to proposals to establish... of flora and fauna, and capacity to attract a broad range of research and educational interests. The...

  15. 15 CFR 921.11 - Site selection and feasibility.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... MANAGEMENT NATIONAL ESTUARINE RESEARCH RESERVE SYSTEM REGULATIONS Site Selection, Post Site Selection and... National Estuarine Research Reserve System. NOAA will give priority consideration to proposals to establish... of flora and fauna, and capacity to attract a broad range of research and educational interests. The...

  16. 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

  17. 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.

  18. 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 information...

  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 information...

  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 information...

  1. 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 information...

  2. 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 information...

  3. SELECTING SITES FOR COMPARISON WITH CREATED WETLANDS

    EPA Science Inventory

    The paper describes the method used for selecting natural wetlands to compare with created wetlands. The results of the selection process and the advantages and disadvantages of the method are discussed. The random site selection method required extensive field work and may have ...

  4. 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

  5. The viking landing sites: selection and certification.

    PubMed

    Masursky, H; Crabill, N L

    1976-08-27

    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 degrees W, 22.4 degrees 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.

  6. [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.

  7. Managing the Public Sector Research and Development Portfolio Selection Process: A Case Study of Quantitative Selection and Optimization

    DTIC Science & Technology

    2016-09-01

    PUBLIC SECTOR RESEARCH & DEVELOPMENT PORTFOLIO SELECTION PROCESS: A CASE STUDY OF QUANTITATIVE SELECTION AND OPTIMIZATION by Jason A. Schwartz...PUBLIC SECTOR RESEARCH & DEVELOPMENT PORTFOLIO SELECTION PROCESS: A CASE STUDY OF QUANTITATIVE SELECTION AND OPTIMIZATION 5. FUNDING NUMBERS 6...describing how public sector organizations can implement a research and development (R&D) portfolio optimization strategy to maximize the cost

  8. Near-optimal experimental design for model selection in systems biology.

    PubMed

    Busetto, Alberto Giovanni; Hauser, Alain; Krummenacher, Gabriel; Sunnåker, Mikael; Dimopoulos, Sotiris; Ong, Cheng Soon; Stelling, Jörg; Buhmann, Joachim M

    2013-10-15

    Biological systems are understood through iterations of modeling and experimentation. Not all experiments, however, are equally valuable for predictive modeling. This study introduces an efficient method for experimental design aimed at selecting dynamical models from data. Motivated by biological applications, the method enables the design of crucial experiments: it determines a highly informative selection of measurement readouts and time points. We demonstrate formal guarantees of design efficiency on the basis of previous results. By reducing our task to the setting of graphical models, we prove that the method finds a near-optimal design selection with a polynomial number of evaluations. Moreover, the method exhibits the best polynomial-complexity constant approximation factor, unless P = NP. We measure the performance of the method in comparison with established alternatives, such as ensemble non-centrality, on example models of different complexity. Efficient design accelerates the loop between modeling and experimentation: it enables the inference of complex mechanisms, such as those controlling central metabolic operation. Toolbox 'NearOED' available with source code under GPL on the Machine Learning Open Source Software Web site (mloss.org).

  9. Turbidity monitoring at select MDOT construction sites.

    DOT National Transportation Integrated Search

    2012-06-01

    The objective of this project was to establish baseline turbidity conditions at select construction : sites by establishing a water quality monitoring program and documenting MDOT approved : BMPs on site. In 2009 the United States Environmental Prote...

  10. 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

  11. [Site selection of nature reserve based on the self-learning tabu search algorithm with space-ecology set covering problem: An example from Daiyun Mountain, Southeast China].

    PubMed

    Huang, Jia Hang; Liu, Jin Fu; Lin, Zhi Wei; Zheng, Shi Qun; He, Zhong Sheng; Zhang, Hui Guang; Li, Wen Zhou

    2017-01-01

    Designing the nature reserves is an effective approach to protecting biodiversity. The traditional approaches to designing the nature reserves could only identify the core area for protecting the species without specifying an appropriate land area of the nature reserve. The site selection approaches, which are based on mathematical model, can select part of the land from the planning area to compose the nature reserve and to protect specific species or ecosystem. They are useful approaches to alleviating the contradiction between ecological protection and development. The existing site selection methods do not consider the ecological differences between each unit and has the bottleneck of computational efficiency in optimization algorithm. In this study, we first constructed the ecological value assessment system which was appropriated for forest ecosystem and that was used for calculating ecological value of Daiyun Mountain and for drawing its distribution map. Then, the Ecological Set Covering Problem (ESCP) was established by integrating the ecological values and then the Space-ecology Set Covering Problem (SSCP) was generated based on the spatial compactness of ESCP. Finally, the STS algorithm which possessed good optimizing performance was utilized to search the approximate optimal solution under diverse protection targets, and the optimization solution of the built-up area of Daiyun Mountain was proposed. According to the experimental results, the difference of ecological values in the spatial distribution was obvious. The ecological va-lue of selected sites of ESCP was higher than that of SCP. SSCP could aggregate the sites with high ecological value based on ESCP. From the results, the level of the aggregation increased with the weight of the perimeter. We suggested that the range of the existing reserve could be expanded for about 136 km 2 and the site of Tsuga longibracteata should be included, which was located in the northwest of the study area. Our

  12. 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.

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

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 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 pipe... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Sample site selection for pipe segment...

  15. 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 pipe...

  16. 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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Optimized Periocular Template Selection for Human Recognition

    PubMed Central

    Sa, Pankaj K.; Majhi, Banshidhar

    2013-01-01

    A novel approach for selecting a rectangular template around periocular region optimally potential for human recognition is proposed. A comparatively larger template of periocular image than the optimal one can be slightly more potent for recognition, but the larger template heavily slows down the biometric system by making feature extraction computationally intensive and increasing the database size. A smaller template, on the contrary, cannot yield desirable recognition though the smaller template performs faster due to low computation for feature extraction. These two contradictory objectives (namely, (a) to minimize the size of periocular template and (b) to maximize the recognition through the template) are aimed to be optimized through the proposed research. This paper proposes four different approaches for dynamic optimal template selection from periocular region. The proposed methods are tested on publicly available unconstrained UBIRISv2 and FERET databases and satisfactory results have been achieved. Thus obtained template can be used for recognition of individuals in an organization and can be generalized to recognize every citizen of a nation. PMID:23984370

  18. Site-Selection in Single-Molecule Junction for Highly Reproducible Molecular Electronics.

    PubMed

    Kaneko, Satoshi; Murai, Daigo; Marqués-González, Santiago; Nakamura, Hisao; Komoto, Yuki; Fujii, Shintaro; Nishino, Tomoaki; Ikeda, Katsuyoshi; Tsukagoshi, Kazuhito; Kiguchi, Manabu

    2016-02-03

    Adsorption sites of molecules critically determine the electric/photonic properties and the stability of heterogeneous molecule-metal interfaces. Then, selectivity of adsorption site is essential for development of the fields including organic electronics, catalysis, and biology. However, due to current technical limitations, site-selectivity, i.e., precise determination of the molecular adsorption site, remains a major challenge because of difficulty in precise selection of meaningful one among the sites. We have succeeded the single site-selection at a single-molecule junction by performing newly developed hybrid technique: simultaneous characterization of surface enhanced Raman scattering (SERS) and current-voltage (I-V) measurements. The I-V response of 1,4-benzenedithiol junctions reveals the existence of three metastable states arising from different adsorption sites. Notably, correlated SERS measurements show selectivity toward one of the adsorption sites: "bridge sites". This site-selectivity represents an essential step toward the reliable integration of individual molecules on metallic surfaces. Furthermore, the hybrid spectro-electric technique reveals the dependence of the SERS intensity on the strength of the molecule-metal interaction, showing the interdependence between the optical and electronic properties in single-molecule junctions.

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

    PubMed

    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.

  20. Gis-Based Site Selection for Underground Natural Resources Using Fuzzy Ahp-Owa

    NASA Astrophysics Data System (ADS)

    Sabzevari, A. R.; Delavar, M. R.

    2017-09-01

    Fuel consumption has significantly increased due to the growth of the population. A solution to address this problem is the underground storage of natural gas. The first step to reach this goal is to select suitable places for the storage. In this study, site selection for the underground natural gas reservoirs has been performed using a multi-criteria decision-making in a GIS environment. The "Ordered Weighted Average" (OWA) operator is one of the multi-criteria decision-making methods for ranking the criteria and consideration of uncertainty in the interaction among the criteria. In this paper, Fuzzy AHP_OWA (FAHP_OWA) is used to determine optimal sites for the underground natural gas reservoirs. Fuzzy AHP_OWA considers the decision maker's risk taking and risk aversion during the decision-making process. Gas consumption rate, temperature, distance from main transportation network, distance from gas production centers, population density and distance from gas distribution networks are the criteria used in this research. Results show that the northeast and west of Iran and the areas around Tehran (Tehran and Alborz Provinces) have a higher attraction for constructing a natural gas reservoir. The performance of the used method was also evaluated. This evaluation was performed using the location of the existing natural gas reservoirs in the country and the site selection maps for each of the quantifiers. It is verified that the method used in this study is capable of modeling different decision-making strategies used by the decision maker with about 88 percent of agreement between the modeling and test data.

  1. 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.

  2. SU-F-R-10: Selecting the Optimal Solution for Multi-Objective Radiomics Model

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

    Zhou, Z; Folkert, M; Wang, J

    2016-06-15

    Purpose: To develop an evidential reasoning approach for selecting the optimal solution from a Pareto solution set obtained by a multi-objective radiomics model for predicting distant failure in lung SBRT. Methods: In the multi-objective radiomics model, both sensitivity and specificity are considered as the objective functions simultaneously. A Pareto solution set with many feasible solutions will be resulted from the multi-objective optimization. In this work, an optimal solution Selection methodology for Multi-Objective radiomics Learning model using the Evidential Reasoning approach (SMOLER) was proposed to select the optimal solution from the Pareto solution set. The proposed SMOLER method used the evidentialmore » reasoning approach to calculate the utility of each solution based on pre-set optimal solution selection rules. The solution with the highest utility was chosen as the optimal solution. In SMOLER, an optimal learning model coupled with clonal selection algorithm was used to optimize model parameters. In this study, PET, CT image features and clinical parameters were utilized for predicting distant failure in lung SBRT. Results: Total 126 solution sets were generated by adjusting predictive model parameters. Each Pareto set contains 100 feasible solutions. The solution selected by SMOLER within each Pareto set was compared to the manually selected optimal solution. Five-cross-validation was used to evaluate the optimal solution selection accuracy of SMOLER. The selection accuracies for five folds were 80.00%, 69.23%, 84.00%, 84.00%, 80.00%, respectively. Conclusion: An optimal solution selection methodology for multi-objective radiomics learning model using the evidential reasoning approach (SMOLER) was proposed. Experimental results show that the optimal solution can be found in approximately 80% cases.« less

  3. 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.

  4. 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 procedure...

  5. 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 procedure...

  6. Prediction of Protein Modification Sites of Pyrrolidone Carboxylic Acid Using mRMR Feature Selection and Analysis

    PubMed Central

    Zheng, Lu-Lu; Niu, Shen; Hao, Pei; Feng, KaiYan; Cai, Yu-Dong; Li, Yixue

    2011-01-01

    Pyrrolidone carboxylic acid (PCA) is formed during a common post-translational modification (PTM) of extracellular and multi-pass membrane proteins. In this study, we developed a new predictor to predict the modification sites of PCA based on maximum relevance minimum redundancy (mRMR) and incremental feature selection (IFS). We incorporated 727 features that belonged to 7 kinds of protein properties to predict the modification sites, including sequence conservation, residual disorder, amino acid factor, secondary structure and solvent accessibility, gain/loss of amino acid during evolution, propensity of amino acid to be conserved at protein-protein interface and protein surface, and deviation of side chain carbon atom number. Among these 727 features, 244 features were selected by mRMR and IFS as the optimized features for the prediction, with which the prediction model achieved a maximum of MCC of 0.7812. Feature analysis showed that all feature types contributed to the modification process. Further site-specific feature analysis showed that the features derived from PCA's surrounding sites contributed more to the determination of PCA sites than other sites. The detailed feature analysis in this paper might provide important clues for understanding the mechanism of the PCA formation and guide relevant experimental validations. PMID:22174779

  7. Optimization methods for activities selection problems

    NASA Astrophysics Data System (ADS)

    Mahad, Nor Faradilah; Alias, Suriana; Yaakop, Siti Zulaika; Arshad, Norul Amanina Mohd; Mazni, Elis Sofia

    2017-08-01

    Co-curriculum activities must be joined by every student in Malaysia and these activities bring a lot of benefits to the students. By joining these activities, the students can learn about the time management and they can developing many useful skills. This project focuses on the selection of co-curriculum activities in secondary school using the optimization methods which are the Analytic Hierarchy Process (AHP) and Zero-One Goal Programming (ZOGP). A secondary school in Negeri Sembilan, Malaysia was chosen as a case study. A set of questionnaires were distributed randomly to calculate the weighted for each activity based on the 3 chosen criteria which are soft skills, interesting activities and performances. The weighted was calculated by using AHP and the results showed that the most important criteria is soft skills. Then, the ZOGP model will be analyzed by using LINGO Software version 15.0. There are two priorities to be considered. The first priority which is to minimize the budget for the activities is achieved since the total budget can be reduced by RM233.00. Therefore, the total budget to implement the selected activities is RM11,195.00. The second priority which is to select the co-curriculum activities is also achieved. The results showed that 9 out of 15 activities were selected. Thus, it can concluded that AHP and ZOGP approach can be used as the optimization methods for activities selection problem.

  8. Using site-selection model to identify suitable sites for seagrass transplantation in the west coast of South Sulawesi

    NASA Astrophysics Data System (ADS)

    Lanuru, Mahatma; Mashoreng, S.; Amri, K.

    2018-03-01

    The success of seagrass transplantation is very much depending on the site selection and suitable transplantation methods. The main objective of this study is to develop and use a site-selection model to identify the suitability of sites for seagrass (Enhalus acoroides) transplantation. Model development was based on the physical and biological characteristics of the transplantation site. The site-selection process is divided into 3 phases: Phase I identifies potential seagrass habitat using available knowledge, removes unnecessary sites before the transplantation test is performed. Phase II involves field assessment and transplantation test of the best scoring areas identified in Phase I. Phase III is the final calculation of the TSI (Transplant Suitability Index), based on results from Phases I and II. The model was used to identify the suitability of sites for seagrass transplantation in the West coast of South Sulawesi (3 sites at Labakkang Coast, 3 sites at Awerange Bay, and 3 sites at Lale-Lae Island). Of the 9 sites, two sites were predicted by the site-selection model to be the most suitable sites for seagrass transplantation: Site II at Labakkang Coast and Site III at Lale-Lae Island.

  9. 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.…

  10. 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.

  11. 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…

  12. 20 CFR 638.303 - Site selection and facilities management.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Site selection and facilities management. 638... Facilities Management § 638.303 Site selection and facilities management. (a) The Job Corps Director shall... center, facilities engineering and real estate management will be conducted by the Job Corps Director or...

  13. 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.

  14. Chromosome segregation drives division site selection in Streptococcus pneumoniae.

    PubMed

    van Raaphorst, Renske; Kjos, Morten; Veening, Jan-Willem

    2017-07-18

    Accurate spatial and temporal positioning of the tubulin-like protein FtsZ is key for proper bacterial cell division. Streptococcus pneumoniae (pneumococcus) is an oval-shaped, symmetrically dividing opportunistic human pathogen lacking the canonical systems for division site control (nucleoid occlusion and the Min-system). Recently, the early division protein MapZ was identified and implicated in pneumococcal division site selection. We show that MapZ is important for proper division plane selection; thus, the question remains as to what drives pneumococcal division site selection. By mapping the cell cycle in detail, we show that directly after replication both chromosomal origin regions localize to the future cell division sites, before FtsZ. Interestingly, Z-ring formation occurs coincidently with initiation of DNA replication. Perturbing the longitudinal chromosomal organization by mutating the condensin SMC, by CRISPR/Cas9-mediated chromosome cutting, or by poisoning DNA decatenation resulted in mistiming of MapZ and FtsZ positioning and subsequent cell elongation. Together, we demonstrate an intimate relationship between DNA replication, chromosome segregation, and division site selection in the pneumococcus, providing a simple way to ensure equally sized daughter cells.

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

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

    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 weremore » 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).« less

  16. Computational Optimization and Characterization of Molecularly Imprinted Polymers

    NASA Astrophysics Data System (ADS)

    Terracina, Jacob J.

    Molecularly imprinted polymers (MIPs) are a class of materials containing sites capable of selectively binding to the imprinted target molecule. Computational chemistry techniques were used to study the effect of different fabrication parameters (the monomer-to-target ratios, pre-polymerization solvent, temperature, and pH) on the formation of the MIP binding sites. Imprinted binding sites were built in silico for the purposes of better characterizing the receptor - ligand interactions. Chiefly, the sites were characterized with respect to their selectivities and the heterogeneity between sites. First, a series of two-step molecular mechanics (MM) and quantum mechanics (QM) computational optimizations of monomer -- target systems was used to determine optimal monomer-to-target ratios for the MIPs. Imidazole- and xanthine-derived target molecules were studied. The investigation included both small-scale models (one-target) and larger scale models (five-targets). The optimal ratios differed between the small and larger scales. For the larger models containing multiple targets, binding-site surface area analysis was used to evaluate the heterogeneity of the sites. The more fully surrounded sites had greater binding energies. Molecular docking was then used to measure the selectivities of the QM-optimized binding sites by comparing the binding energies of the imprinted target to that of a structural analogue. Selectivity was also shown to improve as binding sites become more fully encased by the monomers. For internal sites, docking consistently showed selectivity favoring the molecules that had been imprinted via QM geometry optimizations. The computationally imprinted sites were shown to exhibit size-, shape-, and polarity-based selectivity. This represented a novel approach to investigate the selectivity and heterogeneity of imprinted polymer binding sites, by applying the rapid orientation screening of MM docking to the highly accurate QM-optimized geometries. Next

  17. 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.

  18. Automated training site selection for large-area remote-sensing image analysis

    NASA Astrophysics Data System (ADS)

    McCaffrey, Thomas M.; Franklin, Steven E.

    1993-11-01

    A computer program is presented to select training sites automatically from remotely sensed digital imagery. The basic ideas are to guide the image analyst through the process of selecting typical and representative areas for large-area image classifications by minimizing bias, and to provide an initial list of potential classes for which training sites are required to develop a classification scheme or to verify classification accuracy. Reducing subjectivity in training site selection is achieved by using a purely statistical selection of homogeneous sites which then can be compared to field knowledge, aerial photography, or other remote-sensing imagery and ancillary data to arrive at a final selection of sites to be used to train the classification decision rules. The selection of the homogeneous sites uses simple tests based on the coefficient of variance, the F-statistic, and the Student's i-statistic. Comparisons of site means are conducted with a linear growing list of previously located homogeneous pixels. The program supports a common pixel-interleaved digital image format and has been tested on aerial and satellite optical imagery. The program is coded efficiently in the C programming language and was developed under AIX-Unix on an IBM RISC 6000 24-bit color workstation.

  19. Geospatial Optimization of Siting Large-Scale Solar Projects

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

    Macknick, Jordan; Quinby, Ted; Caulfield, Emmet

    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 withmore » 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.« less

  20. A New Technique of Site Selection for Hardwoods

    Treesearch

    James B. Baker; W. M. Broadfoot

    1978-01-01

    A problem foresters often face in establishing hardwood plantations is selecting proper sites for various species. Before planting, a forest manager should have confidence that a site is suitable for a particular species, and for investment planning he would like to have some idea of the site's potential productivity. This paper describes how to use a new...

  1. CONTAMINANTS AND REMEDIAL OPTIONS AT SELECTED METAL-CONTAMINATED SITES

    EPA Science Inventory

    This document provides information that facilitates characterization of the site and selection of treatment technologies at metals-contaminated sites that would be capable of meeting site-specific cleanup levels. he document does not facilitate the determination of cleanup levels...

  2. 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.

  3. 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.

  4. Training set optimization under population structure in genomic selection.

    PubMed

    Isidro, Julio; Jannink, Jean-Luc; Akdemir, Deniz; Poland, Jesse; Heslot, Nicolas; Sorrells, Mark E

    2015-01-01

    Population structure must be evaluated before optimization of the training set population. Maximizing the phenotypic variance captured by the training set is important for optimal performance. The optimization of the training set (TRS) in genomic selection 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 determination (CDmean), mean of predictor error variance (PEVmean), stratified CDmean (StratCDmean) and random sampling, were evaluated for prediction accuracy in the presence of different levels of population structure. In the presence of population structure, the most phenotypic variation captured by a sampling method in the TRS is desirable. The wheat dataset showed mild population structure, and CDmean and stratified CDmean methods showed the highest accuracies for all the traits except for test weight and heading date. The rice dataset had strong population structure and the approach based on stratified sampling showed the highest accuracies for all traits. In general, CDmean minimized the relationship between genotypes in the TRS, maximizing the relationship between TRS and the test set. This makes it suitable as an optimization criterion for long-term selection. Our results indicated that the best selection criterion used to optimize the TRS seems to depend on the interaction of trait architecture and population structure.

  5. 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

  6. 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.

  7. Design and use of nanostructured single-site heterogeneous catalysts for the selective transformation of fine chemicals.

    PubMed

    Dal Santo, Vladimiro; Liguori, Francesca; Pirovano, Claudio; Guidotti, Matteo

    2010-05-26

    Nanostructured single-site heterogeneous catalysts possess the advantages of classical solid catalysts, in terms of easy recovery and recycling, together with a defined tailored chemical and steric environment around the catalytically active metal site. The use of inorganic oxide supports with selected shape and porosity at a nanometric level may have a relevant impact on the regio- and stereochemistry of the catalytic reaction. Analogously, by choosing the optimal preparation techniques to obtain spatially isolated and well-characterised active sites, it is possible to achieve performances that are comparable to (or, in the most favourable cases, better than) those obtained with homogeneous systems. Such catalysts are therefore particularly suitable for the transformation of highly-functionalised fine chemicals and some relevant examples where high chemo-, regio- and stereoselectivity are crucial will be described.

  8. Applications of Optimal Building Energy System Selection and Operation

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

    Marnay, Chris; Stadler, Michael; Siddiqui, Afzal

    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 bymore » 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.« less

  9. Effects of intraguild predators on nest-site selection by prey.

    PubMed

    Huang, Wen-San; Pike, David A

    2012-01-01

    Nest-site selection involves tradeoffs between the risk of predation (on females and/or nests) and nest-site quality (microenvironment), and consequently suitable nesting sites are often in limited supply. Interactions with "classical" predators (e.g., those not competing for shared resources) can strongly influence nest-site selection, but whether intraguild predation also influences this behavior is unknown. We tested whether risk of predation from an intraguild predator [the diurnal scincid lizard Eutropis (Mabuya) longicaudata] influences nest-site selection by its prey (the nocturnal gecko Gekko hokouensis) on Orchid Island, Taiwan. These two species putatively compete for shared resources, including invertebrate prey and nesting microhabitat, but the larger E. longicaudata also predates G. hokouensis (but not its hard-shelled eggs). Both species nested within a concrete wall containing a series of drainage holes that have either one ("closed-in") or two openings ("open"). In allopatry, E. longicaudata preferred to nest within holes that were plugged by debris (thereby protecting eggs from water intrusion), whereas G. hokouensis selected holes that were open at both ends (facilitating escape from predators). When we experimentally excluded E. longicaudata from its preferred nesting area, G. hokouensis not only nested in higher abundances, but also modified its nest-site selection, such that communal nesting was more prevalent and both open and closed-in holes were used equally. Egg viability was unaffected by the choice of hole type, but was reduced slightly (by 7%) in the predator exclusion area (presumably due to higher local incubation temperatures). Our field experiment demonstrates that intraguild predators can directly influence the nest density of prey by altering maternal nest-site selection behavior, even when the predator and prey are active at different times of day and the eggs are not at risk of predation.

  10. 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

    2017-04-01

    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.

  11. 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…

  12. The OSIRIS-REx Mission Sample Site Selection Process

    NASA Astrophysics Data System (ADS)

    Beshore, Edward C.; Lauretta, Dante

    2014-11-01

    In September of 2016, the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security, REgolith eXplorer) spacecraft will depart for asteroid (101955) Bennu, and in doing so, will turn an important corner in the exploration of the solar system. After arriving at Bennu in the fall of 2018, OSIRIS-REx will undertake a program of observations designed to select a site suitable for retrieving a sample that will be returned to the Earth in 2023. The third mission in NASA’s New Frontiers program, OSIRIS-REx will return over 60 grams from Bennu’s surface.OSIRIS-REx is unique because the science team will have an operational role to play in preparing data products needed to select a sample site. These include products used to ensure flight system safety — topographic maps and shape models, temperature measurements, maps of hazards — as well as assessments of sampleability and science value. The timing and production of these will be presented, as will the high-level decision-making tools and processes for the interim and final site selection processes.

  13. 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

  14. Directing reaction pathways by catalyst active-site selection using self-assembled monolayers.

    PubMed

    Pang, Simon H; Schoenbaum, Carolyn A; Schwartz, Daniel K; Medlin, J Will

    2013-01-01

    One key route for controlling reaction selectivity in heterogeneous catalysis is to prepare catalysts that exhibit only specific types of sites required for desired product formation. Here we show that alkanethiolate self-assembled monolayers with varying surface densities can be used to tune selectivity to desired hydrogenation and hydrodeoxygenation products during the reaction of furfural on supported palladium catalysts. Vibrational spectroscopic studies demonstrate that the selectivity improvement is achieved by controlling the availability of specific sites for the hydrogenation of furfural on supported palladium catalysts through the selection of an appropriate alkanethiolate. Increasing self-assembled monolayer density by controlling the steric bulk of the organic tail ligand restricts adsorption on terrace sites and dramatically increases selectivity to desired products furfuryl alcohol and methylfuran. This technique of active-site selection simultaneously serves both to enhance selectivity and provide insight into the reaction mechanism.

  15. 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. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. 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. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. A Rational Analysis of the Selection Task as Optimal Data Selection.

    ERIC Educational Resources Information Center

    Oaksford, Mike; Chater, Nick

    1994-01-01

    Experimental data on human reasoning in hypothesis-testing tasks is reassessed in light of a Bayesian model of optimal data selection in inductive hypothesis testing. The rational analysis provided by the model suggests that reasoning in such tasks may be rational rather than subject to systematic bias. (SLD)

  18. 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.

  19. 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.

  20. Controlling site selectivity in Pd-catalyzed oxidative cross-coupling reactions.

    PubMed

    Lyons, Thomas W; Hull, Kami L; Sanford, Melanie S

    2011-03-30

    This paper presents a detailed investigation of the factors controlling site selectivity in the Pd-mediated oxidative coupling of 1,3-disubstituted and 1,2,3-trisubstituted arenes (aryl-H) with cyclometalating substrates (L~C-H). The influence of both the concentration and the steric/electronic properties of the quinone promoter are studied in detail. In addition, the effect of steric/electronic modulation of the carboxylate ligand is discussed. Finally, we demonstrate that substitution of the carboxylate for a carbonate X-type ligand leads to a complete reversal in site selectivity for many arene substrates. The origins of these trends in site selectivity are discussed in the context of the mechanism of Pd-catalyzed oxidative cross-coupling.

  1. Constraints and Approach for Selecting the Mars Surveyor '01 Landing Site

    NASA Technical Reports Server (NTRS)

    Golombek, M.; Bridges, N.; Gilmore, M.; Haldemann, A.; Parker, T.; Saunders, R.; Spencer, D.; Smith, J.; Weitz, C.

    1999-01-01

    There are many similarities between the Mars Surveyor '01 (MS '01) landing site selection process and that of Mars Pathfinder. The selection process includes two parallel activities in which engineers define and refine the capabilities of the spacecraft through design, testing and modeling and scientists define a set of landing site constraints based on the spacecraft design and landing scenario. As for Pathfinder, the safety of the site is without question the single most important factor, for the simple reason that failure to land safely yields no science and exposes the mission and program to considerable risk. The selection process must be thorough and defensible and capable of surviving multiple withering reviews similar to the Pathfinder decision. On Pathfinder, this was accomplished by attempting to understand the surface properties of sites using available remote sensing data sets and models based on them. Science objectives are factored into the selection process only after the safety of the site is validated. Finally, as for Pathfinder, the selection process is being done in an open environment with multiple opportunities for community involvement including open workshops, with education and outreach opportunities.

  2. Constraints, Approach, and Status of Mars Surveyor 2001 Landing Site Selection

    NASA Technical Reports Server (NTRS)

    Golombek, M.; Bridges, N.; Briggs, G.; Gilmore, M.; Haldemann, A.; Parker, T.; Saunders, R.; Spencer, D.; Smith, J.; Soderblom, L.

    1999-01-01

    There are many similarities between the Mars Surveyor '01 (MS '01) landing site selection process and that of Mars Pathfinder. The selection process includes two parallel activities in which engineers define and refine the capabilities of the spacecraft through design, testing and modeling and scientists define a set of landing site constraints based on the spacecraft design and landing scenario. As for Pathfinder, the safety of the site is without question the single most important factor, for the simple reason that failure to land safely yields no science and exposes the mission and program to considerable risk. The selection process must be thorough and defensible and capable of surviving multiple withering reviews similar to the Pathfinder decision. On Pathfinder, this was accomplished by attempting to understand the surface properties of sites using available remote sensing data sets and models based on them. Science objectives are factored into the selection process only after the safety of the site is validated. Finally, as for Pathfinder, the selection process is being done in an open environment with multiple opportunities for community involvement including open workshops, with education and outreach opportunities. Additional information is contained in the original extended abstract.

  3. 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.

  4. Copper-catalyst-controlled site-selective allenylation of ketones and aldehydes with propargyl boronates.

    PubMed

    Fandrick, Keith R; Ogikubo, Junichi; Fandrick, Daniel R; Patel, Nitinchandra D; Saha, Jaideep; Lee, Heewon; Ma, Shengli; Grinberg, Nelu; Busacca, Carl A; Senanayake, Chris H

    2013-03-15

    A practical and highly site-selective copper-PhBPE-catalyst-controlled allenylation with propargyl boronates has been developed. The methodology has shown to be tolerant of diverse ketones and aldehydes providing the allenyl adducts in high selectivity. The BPE ligand and boronate substituents were shown to direct the site selectivity for which either propargyl or allenyl adducts can be acquired in high selectivity. A model is proposed that explains the origin of the site selectivity.

  5. Study on site selection of cold chain logistics in northwest territories

    NASA Astrophysics Data System (ADS)

    Liu, Yubin; Ren, Zongwei

    2017-08-01

    In this research, we mainly studied the Site selection problem of cold chain logistics in northwest of China. In the first place, we counted the demands of cold chain products in northwest territories, and then classified it into the Site selection problem in five provinces in northwest territories(Xinjiang, Qinghai, Gansu, Ningxia, Shanxi); Next, we used the Center of gravity Method to select initial location; Finally, we established the location of distribution by using Analytic Hierarchy Process (AHP)and fuzzy comprehensive evaluation method. Comparing with the traditional method, this method not only considered the cost of transportation and distance, but also deliberated the physical condition, social environment and economics condition which associated with Site selection problem.

  6. Optimizing event selection with the random grid search

    NASA Astrophysics Data System (ADS)

    Bhat, Pushpalatha C.; Prosper, Harrison B.; Sekmen, Sezen; Stewart, Chip

    2018-07-01

    The random grid search (RGS) is a simple, but efficient, stochastic algorithm to find optimal cuts that was developed in the context of the search for the top quark at Fermilab in the mid-1990s. The algorithm, and associated code, have been enhanced recently with the introduction of two new cut types, one of which has been successfully used in searches for supersymmetry at the Large Hadron Collider. The RGS optimization algorithm is described along with the recent developments, which are illustrated with two examples from particle physics. One explores the optimization of the selection of vector boson fusion events in the four-lepton decay mode of the Higgs boson and the other optimizes SUSY searches using boosted objects and the razor variables.

  7. 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.

  8. 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.

  9. 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.

  10. The importance of scale-dependent ravine characteristics on breeding-site selection by the Burrowing Parrot, Cyanoliseus patagonus

    PubMed Central

    Rios, Rodrigo S.; Vargas-Rodriguez, Renzo; Novoa-Jerez, Jose-Enrique; Squeo, Francisco A.

    2017-01-01

    characteristics followed by extrinsic variables associated to human disturbance. Likewise, within reproductive ravines, intrinsic characteristics are more strongly related to the number of nests. The probability of producing eggs, however, was related only to distance to roads and human settlements. Patterns suggest that C. patagonus mainly selects nesting sites based on intrinsic morphological characteristics of ravines. Scale differences in the importance of ravine characteristics could be a consequence of the particular orography of the breeding habitat. The arrangement of resources is associated to the location of the gullies rather than to individual ravines, determining the spatial availability and disposition of resources and disturbances. Thus, nest selection is influenced by intrinsic characteristics that maximize the fitness of individuals. Scaling in nest-selection is discussed under an optimality approach that partitions patch selection based on foraging theory. PMID:28462019

  11. Criteria for site selection and frequency allocation (keynote paper), part 5

    NASA Technical Reports Server (NTRS)

    Rottger, J.

    1985-01-01

    Technical aspects of mesosphere-stratosphere-troposphere (MST) Radar on site and frequency selection were discussed. Recommendations on site selections are presented. Tests of interference will be conducted before selecting a site. A small directional antenna may be suitable to simulate sidelobe sensitivity of radars however, sophisticated data-processing methods make system sensitivity extremely good. The use of the complete data system to look for interference is recommended. There is the difficulty of allocation of frequencies -- almost continuous use by these radars will be made when the band 40 to 60 MHz is allocated to other services.

  12. Adaptive feature selection using v-shaped binary particle swarm optimization.

    PubMed

    Teng, Xuyang; 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.

  13. 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

  14. 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

  15. Transferability of optimally-selected climate models in the quantification of climate change impacts on hydrology

    NASA Astrophysics Data System (ADS)

    Chen, Jie; Brissette, François P.; Lucas-Picher, Philippe

    2016-11-01

    Given the ever increasing number of climate change simulations being carried out, it has become impractical to use all of them to cover the uncertainty of climate change impacts. Various methods have been proposed to optimally select subsets of a large ensemble of climate simulations for impact studies. However, the behaviour of optimally-selected subsets of climate simulations for climate change impacts is unknown, since the transfer process from climate projections to the impact study world is usually highly non-linear. Consequently, this study investigates the transferability of optimally-selected subsets of climate simulations in the case of hydrological impacts. Two different methods were used for the optimal selection of subsets of climate scenarios, and both were found to be capable of adequately representing the spread of selected climate model variables contained in the original large ensemble. However, in both cases, the optimal subsets had limited transferability to hydrological impacts. To capture a similar variability in the impact model world, many more simulations have to be used than those that are needed to simply cover variability from the climate model variables' perspective. Overall, both optimal subset selection methods were better than random selection when small subsets were selected from a large ensemble for impact studies. However, as the number of selected simulations increased, random selection often performed better than the two optimal methods. To ensure adequate uncertainty coverage, the results of this study imply that selecting as many climate change simulations as possible is the best avenue. Where this was not possible, the two optimal methods were found to perform adequately.

  16. Optimizing event selection with the random grid search

    DOE PAGES

    Bhat, Pushpalatha C.; Prosper, Harrison B.; Sekmen, Sezen; ...

    2018-02-27

    In this paper, the random grid search (RGS) is a simple, but efficient, stochastic algorithm to find optimal cuts that was developed in the context of the search for the top quark at Fermilab in the mid-1990s. The algorithm, and associated code, have been enhanced recently with the introduction of two new cut types, one of which has been successfully used in searches for supersymmetry at the Large Hadron Collider. The RGS optimization algorithm is described along with the recent developments, which are illustrated with two examples from particle physics. One explores the optimization of the selection of vector bosonmore » fusion events in the four-lepton decay mode of the Higgs boson and the other optimizes SUSY searches using boosted objects and the razor variables.« less

  17. Optimizing Event Selection with the Random Grid Search

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

    Bhat, Pushpalatha C.; Prosper, Harrison B.; Sekmen, Sezen

    2017-06-29

    The random grid search (RGS) is a simple, but efficient, stochastic algorithm to find optimal cuts that was developed in the context of the search for the top quark at Fermilab in the mid-1990s. The algorithm, and associated code, have been enhanced recently with the introduction of two new cut types, one of which has been successfully used in searches for supersymmetry at the Large Hadron Collider. The RGS optimization algorithm is described along with the recent developments, which are illustrated with two examples from particle physics. One explores the optimization of the selection of vector boson fusion events inmore » the four-lepton decay mode of the Higgs boson and the other optimizes SUSY searches using boosted objects and the razor variables.« less

  18. Optimizing event selection with the random grid search

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

    Bhat, Pushpalatha C.; Prosper, Harrison B.; Sekmen, Sezen

    In this paper, the random grid search (RGS) is a simple, but efficient, stochastic algorithm to find optimal cuts that was developed in the context of the search for the top quark at Fermilab in the mid-1990s. The algorithm, and associated code, have been enhanced recently with the introduction of two new cut types, one of which has been successfully used in searches for supersymmetry at the Large Hadron Collider. The RGS optimization algorithm is described along with the recent developments, which are illustrated with two examples from particle physics. One explores the optimization of the selection of vector bosonmore » fusion events in the four-lepton decay mode of the Higgs boson and the other optimizes SUSY searches using boosted objects and the razor variables.« less

  19. Mode perturbation method for optimal guided wave mode and frequency selection.

    PubMed

    Philtron, J H; Rose, J L

    2014-09-01

    With a thorough understanding of guided wave mechanics, researchers can predict which guided wave modes will have a high probability of success in a particular nondestructive evaluation application. However, work continues to find optimal mode and frequency selection for a given application. This "optimal" mode could give the highest sensitivity to defects or the greatest penetration power, increasing inspection efficiency. Since material properties used for modeling work may be estimates, in many cases guided wave mode and frequency selection can be adjusted for increased inspection efficiency in the field. In this paper, a novel mode and frequency perturbation method is described and used to identify optimal mode points based on quantifiable wave characteristics. The technique uses an ultrasonic phased array comb transducer to sweep in phase velocity and frequency space. It is demonstrated using guided interface waves for bond evaluation. After searching nearby mode points, an optimal mode and frequency can be selected which has the highest sensitivity to a defect, or gives the greatest penetration power. The optimal mode choice for a given application depends on the requirements of the inspection. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Supramolecular Recognition Allows Remote, Site-Selective C-H Oxidation of Methylenic Sites in Linear Amines.

    PubMed

    Olivo, Giorgio; Farinelli, Giulio; Barbieri, Alessia; Lanzalunga, Osvaldo; Di Stefano, Stefano; Costas, Miquel

    2017-12-18

    Site-selective C-H functionalization of aliphatic alkyl chains is a longstanding challenge in oxidation catalysis, given the comparable relative reactivity of the different methylenes. A supramolecular, bioinspired approach is described to address this challenge. A Mn complex able to catalyze C(sp 3 )-H hydroxylation with H 2 O 2 is equipped with 18-benzocrown-6 ether receptors that bind ammonium substrates via hydrogen bonding. Reversible pre-association of protonated primary aliphatic amines with the crown ether selectively exposes remote positions (C8 and C9) to the oxidizing unit, resulting in a site-selective oxidation. Remarkably, such control of selectivity retains its efficiency for a whole series of linear amines, overriding the intrinsic reactivity of C-H bonds, no matter the chain length. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. 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

  2. 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

  3. 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.

  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. 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.

  6. Periodical cicadas use light for oviposition site selection

    PubMed Central

    Yang, Louie H

    2006-01-01

    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. PMID:17015354

  7. Parameter Optimization for Selected Correlation Analysis of Intracranial Pathophysiology.

    PubMed

    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.

  8. 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

  9. EGU2013 SM1.4/GI1.6 session: "Improving seismic networks performances: from site selection to data integration"

    NASA Astrophysics Data System (ADS)

    Pesaresi, D.; Busby, R.

    2013-08-01

    The number and quality of seismic stations and networks in Europe continually improves, nevertheless there is always scope to optimize their performance. In this session we welcomed contributions from all aspects of seismic network installation, operation and management. This includes site selection; equipment testing and installation; planning and implementing communication paths; policies for redundancy in data acquisition, processing and archiving; and integration of different datasets including GPS and OBS.

  10. 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.

  11. Site Selection Appraisal for Tidal Turbine Development in the River Mersey

    NASA Astrophysics Data System (ADS)

    Kelly, C. L.; Blanco-Davis, E.; Michailides, C.; Davies, P. A.; Wang, J.

    2018-03-01

    This paper used a specialist software package to produce a detailed model of the River Mersey estuary, which can be subjected to a range of simulated tidal conditions. The aim of this research was to use the validated model to identify the optimal location for the positioning of a tidal turbine. Progress was made identifying a new optimal site for power generation using velocity data produced from simulations conducted using the MIKE 3 software. This process resulted in the identification of site 8, which sits mid-river between the Morpeth Dock and the Albert Dock, being identified as the favoured location for tidal power generation in the River Mersey. Further analysis of the site found that a 17.2-m diameter single rota multidirectional turbine with a 428-kW-rated capacity could produce 1.12 GWh annually.

  12. Quantum dot laser optimization: selectively doped layers

    NASA Astrophysics Data System (ADS)

    Korenev, Vladimir V.; Konoplev, Sergey S.; Savelyev, Artem V.; Shernyakov, Yurii M.; Maximov, Mikhail V.; Zhukov, Alexey E.

    2016-08-01

    Edge emitting quantum dot (QD) lasers are discussed. It has been recently proposed to use modulation p-doping of the layers that are adjacent to QD layers in order to control QD's charge state. Experimentally it has been proven useful to enhance ground state lasing and suppress the onset of excited state lasing at high injection. These results have been also confirmed with numerical calculations involving solution of drift-diffusion equations. However, deep understanding of physical reasons for such behavior and laser optimization requires analytical approaches to the problem. In this paper, under a set of assumptions we provide an analytical model that explains major effects of selective p-doping. Capture rates of elections and holes can be calculated by solving Poisson equations for electrons and holes around the charged QD layer. The charge itself is ruled by capture rates and selective doping concentration. We analyzed this self-consistent set of equations and showed that it can be used to optimize QD laser performance and to explain underlying physics.

  13. A parallel optimization method for product configuration and supplier selection based on interval

    NASA Astrophysics Data System (ADS)

    Zheng, Jian; Zhang, Meng; Li, Guoxi

    2017-06-01

    In the process of design and manufacturing, product configuration is an important way of product development, and supplier selection is an essential component of supply chain management. To reduce the risk of procurement and maximize the profits of enterprises, this study proposes to combine the product configuration and supplier selection, and express the multiple uncertainties as interval numbers. An integrated optimization model of interval product configuration and supplier selection was established, and NSGA-II was put forward to locate the Pareto-optimal solutions to the interval multiobjective optimization model.

  14. 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... designation promulgation as an environmental assessment of the impact of the use of the site for disposal, and...

  15. 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

  16. 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.

  17. 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.

  18. 23 CFR 1340.5 - Selection of observation sites.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... STATE OBSERVATIONAL SURVEYS OF SEAT BELT USE Survey Design Requirements § 1340.5 Selection of... observation sites. The survey design shall include at a minimum the following protocols: (1) Protocol when...

  19. 23 CFR 1340.5 - Selection of observation sites.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... STATE OBSERVATIONAL SURVEYS OF SEAT BELT USE Survey Design Requirements § 1340.5 Selection of... observation sites. The survey design shall include at a minimum the following protocols: (1) Protocol when...

  20. 23 CFR 1340.5 - Selection of observation sites.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... STATE OBSERVATIONAL SURVEYS OF SEAT BELT USE Survey Design Requirements § 1340.5 Selection of... observation sites. The survey design shall include at a minimum the following protocols: (1) Protocol when...

  1. 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.

  2. 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.

  3. [Academic burnout and selection-optimization-compensation strategy in medical students].

    PubMed

    Chun, Kyung Hee; Park, Young Soon; Lee, Young Hwan; Kim, Seong Yong

    2014-12-01

    This study was conducted to examine the relationship between academic demand, academic burnout, and the selection-optimization-compensation (SOC) strategy in medical students. A total of 317 students at Yeungnam University, comprising 90 premedical course students, 114 medical course students, and 113 graduate course students, completed a survey that addressed the factors of academic burnout and the selection-optimization-compensation strategy. We analyzed variances of burnout and SOC strategy use by group, and stepwise multiple regression analysis was conducted. There were significant differences in emotional exhaustion and cynicism between groups and year in school. In the SOC strategy, there were no significant differences between groups except for elective selection. The second-year medical and graduate students experienced significantly greater exhaustion (p<0.001), and first-year premedical students experienced significantly higher cynicism (p<0.001). By multiple regression analysis, subfactors of academic burnout and emotional exhaustion were significantly affected by academic demand (p<0.001), and 46% of the variance was explained. Cynicism was significantly affected by elective selection (p<0.05), and inefficacy was significantly influenced by optimization (p<0.001). To improve adaptation, prescriptive strategies and preventive support should be implemented with regard to academic burnout in medical school. Longitudinal and qualitative studies on burnout must be conducted.

  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. Territory and nest site selection patterns by Grasshopper Sparrows in southeastern Arizona

    USGS Publications Warehouse

    Ruth, Janet M.; Skagen, Susan K.

    2017-01-01

    Grassland bird populations are showing some of the greatest rates of decline of any North American birds, prompting measures to protect and improve important habitat. We assessed how vegetation structure and composition, habitat features often targeted for management, affected territory and nest site selection by Grasshopper Sparrows (Ammodramus savannarum ammolegus) in southeastern Arizona. To identify features important to males establishing territories, we compared vegetation characteristics of known territories and random samples on 2 sites over 5 years. We examined habitat selection patterns of females by comparing characteristics of nest sites with territories over 3 years. Males selected territories in areas of sparser vegetation structure and more tall shrubs (>2 m) than random plots on the site with low shrub densities. Males did not select territories based on the proportion of exotic grasses. Females generally located nest sites in areas with lower small shrub (1–2 m tall) densities than territories overall when possible and preferentially selected native grasses for nest construction. Whether habitat selection was apparent depended upon the range of vegetation structure that was available. We identified an upper threshold above which grass structure seemed to be too high and dense for Grasshopper Sparrows. Our results suggest that some management that reduces vegetative structure may benefit this species in desert grasslands at the nest and territory scale. However, we did not assess initial male habitat selection at a broader landscape scale where their selection patterns may be different and could be influenced by vegetation density and structure outside the range of values sampled in this study.

  6. Opposing selection and environmental variation modify optimal timing of breeding.

    PubMed

    Tarwater, Corey E; Beissinger, Steven R

    2013-09-17

    Studies of evolution in wild populations often find that the heritable phenotypic traits of individuals producing the most offspring do not increase proportionally in the population. This paradox may arise when phenotypic traits influence both fecundity and viability and when there is a tradeoff between these fitness components, leading to opposing selection. Such tradeoffs are the foundation of life history theory, but they are rarely investigated in selection studies. Timing of breeding is a classic example of a heritable trait under directional selection that does not result in an evolutionary response. Using a 22-y study of a tropical parrot, we show that opposing viability and fecundity selection on the timing of breeding is common and affects optimal breeding date, defined by maximization of fitness. After accounting for sampling error, the directions of viability (positive) and fecundity (negative) selection were consistent, but the magnitude of selection fluctuated among years. Environmental conditions (rainfall and breeding density) primarily and breeding experience secondarily modified selection, shifting optimal timing among individuals and years. In contrast to other studies, viability selection was as strong as fecundity selection, late-born juveniles had greater survival than early-born juveniles, and breeding later in the year increased fitness under opposing selection. Our findings provide support for life history tradeoffs influencing selection on phenotypic traits, highlight the need to unify selection and life history theory, and illustrate the importance of monitoring survival as well as reproduction for understanding phenological responses to climate change.

  7. Site-selective and stereoselective functionalization of non-activated tertiary C-H bonds

    NASA Astrophysics Data System (ADS)

    Liao, Kuangbiao; Pickel, Thomas C.; Boyarskikh, Vyacheslav; Bacsa, John; Musaev, Djamaladdin G.; Davies, Huw M. L.

    2017-11-01

    The synthesis of complex organic compounds usually relies on controlling the reactions of the functional groups. In recent years, it has become possible to carry out reactions directly on the C-H bonds, previously considered to be unreactive. One of the major challenges is to control the site-selectivity because most organic compounds have many similar C-H bonds. The most well developed procedures so far rely on the use of substrate control, in which the substrate has one inherently more reactive C-H bond or contains a directing group or the reaction is conducted intramolecularly so that a specific C-H bond is favoured. A more versatile but more challenging approach is to use catalysts to control which site in the substrate is functionalized. p450 enzymes exhibit C-H oxidation site-selectivity, in which the enzyme scaffold causes a specific C-H bond to be functionalized by placing it close to the iron-oxo haem complex. Several studies have aimed to emulate this enzymatic site-selectivity with designed transition-metal catalysts but it is difficult to achieve exceptionally high levels of site-selectivity. Recently, we reported a dirhodium catalyst for the site-selective functionalization of the most accessible non-activated (that is, not next to a functional group) secondary C-H bonds by means of rhodium-carbene-induced C-H insertion. Here we describe another dirhodium catalyst that has a very different reactivity profile. Instead of the secondary C-H bond, the new catalyst is capable of precise site-selectivity at the most accessible tertiary C-H bonds. Using this catalyst, we modify several natural products, including steroids and a vitamin E derivative, indicating the applicability of this method of synthesis to the late-stage functionalization of complex molecules. These studies show it is possible to achieve site-selectivity at different positions within a substrate simply by selecting the appropriate catalyst. We hope that this work will inspire the design of

  8. 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

  9. 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.

  10. Effects of transcriptional start site sequence and position on nucleotide-sensitive selection of alternative start sites at the pyrC promoter in Escherichia coli.

    PubMed Central

    Liu, J; Turnbough, C L

    1994-01-01

    In Escherichia coli, expression of the pyrC gene is regulated primarily by a translational control mechanism based on nucleotide-sensitive selection of transcriptional start sites at the pyrC promoter. When intracellular levels of CTP are high, pyrC transcripts are initiated predominantly with CTP at a site 7 bases downstream of the Pribnow box. These transcripts form a stable hairpin at their 5' ends that blocks ribosome binding. When the CTP level is low and the GTP level is high, conditions found in pyrimidine-limited cells, transcripts are initiated primarily with GTP at a site 9 bases downstream of the Pribnow box. These shorter transcripts are unable to form a hairpin at their 5' ends and are readily translated. In this study, we examined the effects of nucleotide sequence and position on the selection of transcriptional start sites at the pyrC promoter. We characterized promoter mutations that systematically alter the sequence at position 7 or 9 downstream of the Pribnow box or vary the spacing between the Pribnow box and wild-type transcriptional initiation region. The results reveal preferences for particular initiating nucleotides (ATP > or = GTP > UTP >> CTP) and for starting positions downstream of the Pribnow box (7 >> 6 and 8 > 9 > 10). The results indicate that optimal nucleotide-sensitive start site switching at the wild-type pyrC promoter is the result of competition between the preferred start site (position 7) that uses the poorest initiating nucleotide (CTP) and a weak start site (position 9) that uses a good initiating nucleotide (GTP). The sequence of the pyrC promoter also minimizes the synthesis of untranslatable transcripts and provides for maximum stability of the regulatory transcript hairpin. In addition, the results show that the effects of the mutations on pyrC expression and regulation are consistent with the current model for translational control. Possible effects of preferences for initiating nucleotides and start sites on the

  11. A quantitative model of optimal data selection in Wason's selection task.

    PubMed

    Hattori, Masasi

    2002-10-01

    The optimal data selection model proposed by Oaksford and Chater (1994) successfully formalized Wason's selection task (Wason, 1966). The model, however, involved some questionable assumptions and was also not sufficient as a model of the task because it could not provide quantitative predictions of the card selection frequencies. In this paper, the model was revised to provide quantitative fits to the data. The model can predict the selection frequencies of cards based on a selection tendency function (STF), or conversely, it enables the estimation of subjective probabilities from data. Past experimental data were first re-analysed based on the model. In Experiment 1, the superiority of the revised model was shown. However, when the relationship between antecedent and consequent was forced to deviate from the biconditional form, the model was not supported. In Experiment 2, it was shown that sufficient emphasis on probabilistic information can affect participants' performance. A detailed experimental method to sort participants by probabilistic strategies was introduced. Here, the model was supported by a subgroup of participants who used the probabilistic strategy. Finally, the results were discussed from the viewpoint of adaptive rationality.

  12. Eucalyptus Energy Farm: feasibility study and demonstration. Phase 1: site and species selection

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

    Mariani, E.O.; Wood, W.A.; Kouchoukos, P.C.

    1978-06-01

    The results of investigations to determine the feasibility for establishing ''Eucalyptus Energy Farms'' as a potential source of biomass derived energy are presented. Included in this report are: the results of an extensive literature search and numerous field interviews (both domestically and internationally) to identify those Eucalyptus species most suitable for use within the United States; a description of the site selection criteria, site selection process, and identification of potential sites for use in testing the Eucalyptus Energy Farm concept; a description of the Eucalyptus species selection criteria, species selection process, and an identification of the specific species recommended formore » testing at specific sites; preliminary engineering designs for each of the proposed plantation sites; and environmental impact considerations related to Eucalyptus growing. It is concluded that although the Eucalyptus are extremely temperature sensitive and the geographic areas which appear suitable for their planting (within the United States) are principally confined to western and central California and the warmest regions of the southeastern United States, each of the areas contain large amounts of marginal land which could be converted into Eucalyptus based biomass plantations. Suitable sites, which are representative of the larger marginal land areas, are immediately available for use in establishing Eucalyptus screening test sites. Furthermore, there are not significant environmental conditions which would preclude the establishment of these initial test sites. It is therefore recommended that efforts be initiated to obtain selected provenances of Eucalyptus seeds (of the designated species) for further field testing and data collection within the United States, and that actual site selection be initiated.« less

  13. 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.

  14. Optimization of selection for growth in Menz Sheep while minimizing inbreeding depression in fitness traits

    PubMed Central

    2013-01-01

    The genetic trends in fitness (inbreeding, fertility and survival) of a closed nucleus flock of Menz sheep under selection during ten years for increased body weight were investigated to evaluate the consequences of selection for body weight on fitness. A mate selection tool was used to optimize in retrospect the actual selection and matings conducted over the project period to assess if the observed genetic gains in body weight could have been achieved with a reduced level of inbreeding. In the actual selection, the genetic trends for yearling weight, fertility of ewes and survival of lambs were 0.81 kg, –0.00026% and 0.016% per generation. The average inbreeding coefficient remained zero for the first few generations and then tended to increase over generations. The genetic gains achieved with the optimized retrospective selection and matings were highly comparable with the observed values, the correlation between the average breeding values of lambs born from the actual and optimized matings over the years being 0.99. However, the level of inbreeding with the optimized mate selections remained zero until late in the years of selection. Our results suggest that an optimal selection strategy that considers both genetic merits and coancestry of mates should be adopted to sustain the Menz sheep breeding program. PMID:23783076

  15. 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.

  16. Effect of Methodological and Ecological Approaches on Heterogeneity of Nest-Site Selection of a Long-Lived Vulture

    PubMed Central

    Moreno-Opo, Rubén; Fernández-Olalla, Mariana; Margalida, Antoni; Arredondo, Ángel; Guil, Francisco

    2012-01-01

    The application of scientific-based conservation measures requires that sampling methodologies in studies modelling similar ecological aspects produce comparable results making easier their interpretation. We aimed to show how the choice of different methodological and ecological approaches can affect conclusions in nest-site selection studies along different Palearctic meta-populations of an indicator species. First, a multivariate analysis of the variables affecting nest-site selection in a breeding colony of cinereous vulture (Aegypius monachus) in central Spain was performed. Then, a meta-analysis was applied to establish how methodological and habitat-type factors determine differences and similarities in the results obtained by previous studies that have modelled the forest breeding habitat of the species. Our results revealed patterns in nesting-habitat modelling by the cinereous vulture throughout its whole range: steep and south-facing slopes, great cover of large trees and distance to human activities were generally selected. The ratio and situation of the studied plots (nests/random), the use of plots vs. polygons as sampling units and the number of years of data set determined the variability explained by the model. Moreover, a greater size of the breeding colony implied that ecological and geomorphological variables at landscape level were more influential. Additionally, human activities affected in greater proportion to colonies situated in Mediterranean forests. For the first time, a meta-analysis regarding the factors determining nest-site selection heterogeneity for a single species at broad scale was achieved. It is essential to homogenize and coordinate experimental design in modelling the selection of species' ecological requirements in order to avoid that differences in results among studies would be due to methodological heterogeneity. This would optimize best conservation and management practices for habitats and species in a global context

  17. Selection of the InSight landing site

    USGS Publications Warehouse

    Golombek, M.; Kipp, D.; Warner, N.; Daubar, Ingrid J.; Fergason, Robin L.; Kirk, Randolph L.; Beyer, R.; Huertas, A.; Piqueux, Sylvain; Putzig, N.E.; Campbell, B.A.; Morgan, G. A.; Charalambous, C.; Pike, W. T.; Gwinner, K.; Calef, F.; Kass, D.; Mischna, M A; 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.E.; Lognonne, P.; Banerdt, W. B.

    2017-01-01

    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">≤−2.5 km≤−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.

  18. 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

  19. Gradient stationary phase optimized selectivity liquid chromatography with conventional columns.

    PubMed

    Chen, Kai; Lynen, Frédéric; Szucs, Roman; Hanna-Brown, Melissa; Sandra, Pat

    2013-05-21

    Stationary phase optimized selectivity liquid chromatography (SOSLC) is a promising technique to optimize the selectivity of a given separation. By combination of different stationary phases, SOSLC offers excellent possibilities for method development under both isocratic and gradient conditions. The so far available commercial SOSLC protocol utilizes dedicated column cartridges and corresponding cartridge holders to build up the combined column of different stationary phases. The present work is aimed at developing and extending the gradient SOSLC approach towards coupling conventional columns. Generic tubing was used to connect short commercially available LC columns. Fast and base-line separation of a mixture of 12 compounds containing phenones, benzoic acids and hydroxybenzoates under both isocratic and linear gradient conditions was selected to demonstrate the potential of SOSLC. The influence of the connecting tubing on the deviation of predictions is also discussed.

  20. An opinion formation based binary optimization approach for feature selection

    NASA Astrophysics Data System (ADS)

    Hamedmoghadam, Homayoun; Jalili, Mahdi; Yu, Xinghuo

    2018-02-01

    This paper proposed a novel optimization method based on opinion formation in complex network systems. The proposed optimization technique mimics human-human interaction mechanism based on a mathematical model derived from social sciences. Our method encodes a subset of selected features to the opinion of an artificial agent and simulates the opinion formation process among a population of agents to solve the feature selection problem. The agents interact using an underlying interaction network structure and get into consensus in their opinions, while finding better solutions to the problem. A number of mechanisms are employed to avoid getting trapped in local minima. We compare the performance of the proposed method with a number of classical population-based optimization methods and a state-of-the-art opinion formation based method. Our experiments on a number of high dimensional datasets reveal outperformance of the proposed algorithm over others.

  1. Pesticide alters oviposition site selection in gray treefrogs.

    PubMed

    Vonesh, James R; Buck, Julia C

    2007-11-01

    Understanding the impacts of pesticides on non-target organisms is an important issue for conservation biology. Research into the environmental consequences of pesticides has largely focused on pesticide toxicity. We have less understanding of the nonlethal effects of pesticides, and the consequences of nonlethal effects for species and communities. For example, we know very little about whether pesticides alter habitat selection behavior. Understanding whether pesticides alter habitat selection is important because pesticide-induced shifts in habitat selection could either magnify or reduce the toxic effects of contaminants by funneling organisms into or directing them away from contaminated sites. Here we present four field experiments that examine the effect of the commercial pesticide Sevin and its active ingredient, carbaryl, on oviposition site selection by the gray treefrog (Hyla chrysoscelis). Our results show that uncontaminated pools consistently received 2-3 times more eggs than contaminated pools; that treefrogs appeared to respond to Sevin directly, not indirectly via its effects on the aquatic food web, and that this preference persisted across a range of temporal and spatial scales. Both Sevin and carbaryl per se reduced oviposition, while other volatile chemicals (e.g., our solvent control, acetone) had no effect. These findings suggest that in order to understanding the consequences of contaminants in aquatic systems we will need to consider not only toxicity, but also how contaminant effects on habitat selection alter the way organisms distribute themselves in the environment.

  2. 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. © 2014 Wiley Periodicals, Inc.

  3. Analytic hierarchy process helps select site for limestone quarry expansion in Barbados.

    PubMed

    Dey, Prasanta Kumar; Ramcharan, Eugene K

    2008-09-01

    Site selection is a key activity for quarry expansion to support cement production, and is governed by factors such as resource availability, logistics, costs, and socio-economic-environmental factors. Adequate consideration of all the factors facilitates both industrial productivity and sustainable economic growth. This study illustrates the site selection process that was undertaken for the expansion of limestone quarry operations to support cement production in Barbados. First, alternate sites with adequate resources to support a 25-year development horizon were identified. Second, technical and socio-economic-environmental factors were then identified. Third, a database was developed for each site with respect to each factor. Fourth, a hierarchical model in analytic hierarchy process (AHP) framework was then developed. Fifth, the relative ranking of the alternate sites was then derived through pair wise comparison in all the levels and through subsequent synthesizing of the results across the hierarchy through computer software (Expert Choice). The study reveals that an integrated framework using the AHP can help select a site for the quarry expansion project in Barbados.

  4. Landfill site selection by using geographic information systems

    NASA Astrophysics Data System (ADS)

    Şener, Başak; Süzen, M. Lütfi; Doyuran, Vedat

    2006-01-01

    One of the serious and growing potential problems in most large urban areas is the shortage of land for waste disposal. Although there are some efforts to reduce and recover the waste, disposal in landfills is still the most common method for waste destination. An inappropriate landfill site may have negative environmental, economic and ecological impacts. Therefore, it should be selected carefully by considering both regulations and constraints on other sources. In this study, candidate sites for an appropriate landfill area in the vicinity of Ankara are determined by using the integration of geographic information systems and multicriteria decision analysis (MCDA). For this purpose, 16 input map layers including topography, settlements (urban centers and villages), roads (Highway E90 and village roads), railways, airport, wetlands, infrastructures (pipelines and power lines), slope, geology, land use, floodplains, aquifers and surface water are prepared and two different MCDA methods (simple additive weighting and analytic hierarchy process) are implemented to a geographical information system. Comparison of the maps produced by these two different methods shows that both methods yield conformable results. Field checks also confirm that the candidate sites agree well with the selected criteria.

  5. Kynurenic acid analogues with improved affinity and selectivity for the glycine site on the N-methyl-D-aspartate receptor from rat brain.

    PubMed

    Foster, A C; Kemp, J A; Leeson, P D; Grimwood, S; Donald, A E; Marshall, G R; Priestley, T; Smith, J D; Carling, R W

    1992-05-01

    The glycine site on the N-methyl-D-aspartate (NMDA) subtype of receptors for the excitatory neurotransmitter glutamate is a potential target for the development of neuroprotective drugs. We report here two chemical series of glycine site antagonists derived from kynurenic acid (KYNA), with greatly improved potency and selectivity. Disubstitution with chlorine or bromine in the 5- and 7-positions of KYNA increased affinity for [3H]glycine binding sites in rat cortex/hippocampus P2 membranes, with a parallel increase of potency for antagonism of NMDA-evoked responses in the rat cortical wedge preparation. The optimal compound was 5-I,7-Cl-KYNA, with an IC50 for [3H]glycine binding of 29 nM and an apparent Kb in the cortical wedge preparation of 0.41 microM. Reduction of the right-hand ring of 5,7-diCl-KYNA reduced affinity by 10-fold, but this was restored by substitution in the 4-position with the trans-phenylamide and further improved in the trans-benzylamide. The optimal compound was the transphenylurea (L-689,560), with an IC50 of 7.4 nM and an apparent Kb of 0.13 microM. Both series of compounds displayed a high degree of selectivity for the glycine site, having IC50 values of greater than 10 microM versus radioligand binding to the glutamate recognition sites of NMDA, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA), and kainate receptors and the strychnine-sensitive glycine receptor. Selectivity versus AMPA receptor-mediated responses was also apparent in the rat cortical wedge and in patch-clamp recordings of cortical neurons in culture. Experiments using [3H]dizocilpine (MK-801) binding indicated that 5,7-diBr-KYNA, 5,7-diCl-KYNA, 5-I,7-Cl-KYNA, and L-689,560 all behaved as full antagonists and were competitive with glycine. Patch-clamp recordings of cortical neurons in culture also indicated that NMDA-induced currents were antagonized by competition for the glycine site, and gave no evidence for partial agonist activity. pKi values for 5,7-di

  6. 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.

  7. 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.

  8. Selection on Inversion Breakpoints Favors Proximity to Pairing Sensitive Sites in Drosophila melanogaster.

    PubMed

    Corbett-Detig, Russell B

    2016-09-01

    Chromosomal inversions are widespread among taxa, and have been implicated in a number of biological processes including adaptation, sex chromosome evolution, and segregation distortion. Consistent with selection favoring linkage between loci, it is well established that length is a selected trait of inversions. However, the factors that affect the distribution of inversion breakpoints remain poorly understood. "Sensitive sites" have been mapped on all euchromatic chromosome arms in Drosophila melanogaster, and may be a source of natural selection on inversion breakpoint positions. Briefly, sensitive sites are genomic regions wherein proximal structural rearrangements result in large reductions in local recombination rates in heterozygotes. Here, I show that breakpoints of common inversions are significantly more likely to lie within a cytological band containing a sensitive site than are breakpoints of rare inversions. Furthermore, common inversions for which neither breakpoint intersects a sensitive site are significantly longer than rare inversions, but common inversions whose breakpoints intersect a sensitive site show no evidence for increased length. I interpret these results to mean that selection favors inversions whose breakpoints disrupt synteny near to sensitive sites, possibly because these inversions suppress recombination in large genomic regions. To my knowledge this is the first evidence consistent with positive selection acting on inversion breakpoint positions. Copyright © 2016 by the Genetics Society of America.

  9. 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.

  10. A novel channel selection method for optimal classification in different motor imagery BCI paradigms.

    PubMed

    Shan, Haijun; Xu, Haojie; Zhu, Shanan; He, Bin

    2015-10-21

    For sensorimotor rhythms based brain-computer interface (BCI) systems, classification of different motor imageries (MIs) remains a crucial problem. An important aspect is how many scalp electrodes (channels) should be used in order to reach optimal performance classifying motor imaginations. While the previous researches on channel selection mainly focus on MI tasks paradigms without feedback, the present work aims to investigate the optimal channel selection in MI tasks paradigms with real-time feedback (two-class control and four-class control paradigms). In the present study, three datasets respectively recorded from MI tasks experiment, two-class control and four-class control experiments were analyzed offline. Multiple frequency-spatial synthesized features were comprehensively extracted from every channel, and a new enhanced method IterRelCen was proposed to perform channel selection. IterRelCen was constructed based on Relief algorithm, but was enhanced from two aspects: change of target sample selection strategy and adoption of the idea of iterative computation, and thus performed more robust in feature selection. Finally, a multiclass support vector machine was applied as the classifier. The least number of channels that yield the best classification accuracy were considered as the optimal channels. One-way ANOVA was employed to test the significance of performance improvement among using optimal channels, all the channels and three typical MI channels (C3, C4, Cz). The results show that the proposed method outperformed other channel selection methods by achieving average classification accuracies of 85.2, 94.1, and 83.2 % for the three datasets, respectively. Moreover, the channel selection results reveal that the average numbers of optimal channels were significantly different among the three MI paradigms. It is demonstrated that IterRelCen has a strong ability for feature selection. In addition, the results have shown that the numbers of optimal

  11. Photoactivable antibody binding protein: site-selective and covalent coupling of antibody.

    PubMed

    Jung, Yongwon; Lee, Jeong Min; Kim, Jung-won; Yoon, Jeongwon; Cho, Hyunmin; Chung, Bong Hyun

    2009-02-01

    Here we report new photoactivable antibody binding proteins, which site-selectively capture antibodies and form covalent conjugates with captured antibodies upon irradiation. The proteins allow the site-selective tagging and/or immobilization of antibodies with a highly preferred orientation and omit the need for prior antibody modifications. The minimal Fc-binding domain of protein G, a widely used antibody binding protein, was genetically and chemically engineered to contain a site-specific photo cross-linker, benzophenone. In addition, the domain was further mutated to have an enhanced Fc-targeting ability. This small engineered protein was successfully cross-linked only to the Fc region of the antibody without any nonspecific reactivity. SPR analysis indicated that antibodies can be site-selectively biotinylated through the present photoactivable protein. Furthermore, the system enabled light-induced covalent immobilization of antibodies directly on various solid surfaces, such as those of glass slides, gold chips, and small particles. Antibody coupling via photoactivable antibody binding proteins overcomes several limitations of conventional approaches, such as random chemical reactions or reversible protein binding, and offers a versatile tool for the field of immunosensors.

  12. Constraints, Approach and Present Status for Selecting the Mars Surveyor 2001 Landing Site

    NASA Technical Reports Server (NTRS)

    Golombek, M.; Anderson, F.; Bridges, N.; Briggs, G.; Gilmore, M.; Gulick, V.; Haldemann, A.; Parker, T.; Saunders, R.; Spencer, D.; hide

    1999-01-01

    There are many similarities between the Mars Surveyor '01 (MS '01) landing site selection process and that of Mars Pathfinder. The selection process includes two parallel activities in which engineers define and refine the capabilities of the spacecraft through design, testing and modeling and scientists define a set of landing site constraints based on the spacecraft design and landing scenario. As for Pathfinder, the safety of the site is without question the single most important factor, for the simple reason that failure to land safely yields no science and exposes the mission and program to considerable risk. The selection process must be thorough, defensible and capable of surviving multiple withering reviews similar to the Pathfinder decision. On Pathfinder, this was accomplished by attempting to understand the surface properties of sites using available remote sensing data sets and models based on them. Science objectives are factored into the selection process only after the safety of the site is validated. Finally, as for Pathfinder, the selection process is being done in an open environment with multiple opportunities for community involvement including open workshops, with education and outreach opportunities.

  13. 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.

  14. 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.

  15. Communities ready for takeoffIntegrating social assets for biofuel site-selection modeling.

    PubMed

    Rijkhoff, Sanne A M; Hoard, Season A; Gaffney, Michael J; Smith, Paul M

    2017-01-01

    Although much of the social science literature supports the importance of community assets for success in many policy areas, these assets are often overlooked when selecting communities for new infrastructure facilities. Extensive collaboration is crucial for the success of environmental and economic projects, yet it often is not adequately addressed when making siting decisions for new projects. This article develops a social asset framework that includes social, creative, and human capital to inform site-selection decisions. This framework is applied to the Northwest Advanced Renewables Alliance project to assess community suitability for biofuel-related developments. This framework is the first to take all necessary community assets into account, providing insight into successful site selection beyond current models. The framework not only serves as a model for future biorefinery projects but also guides tasks that depend on informed location selection for success.

  16. Automating an integrated spatial data-mining model for landfill site selection

    NASA Astrophysics Data System (ADS)

    Abujayyab, Sohaib K. M.; Ahamad, Mohd Sanusi S.; Yahya, Ahmad Shukri; Ahmad, Siti Zubaidah; Aziz, Hamidi Abdul

    2017-10-01

    An integrated programming environment represents a robust approach to building a valid model for landfill site selection. One of the main challenges in the integrated model is the complicated processing and modelling due to the programming stages and several limitations. An automation process helps avoid the limitations and improve the interoperability between integrated programming environments. This work targets the automation of a spatial data-mining model for landfill site selection by integrating between spatial programming environment (Python-ArcGIS) and non-spatial environment (MATLAB). The model was constructed using neural networks and is divided into nine stages distributed between Matlab and Python-ArcGIS. A case study was taken from the north part of Peninsular Malaysia. 22 criteria were selected to utilise as input data and to build the training and testing datasets. The outcomes show a high-performance accuracy percentage of 98.2% in the testing dataset using 10-fold cross validation. The automated spatial data mining model provides a solid platform for decision makers to performing landfill site selection and planning operations on a regional scale.

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

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

    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 boreholemore » is located kilometers away.« less

  18. Simple summation rule for optimal fixation selection in visual search.

    PubMed

    Najemnik, Jiri; Geisler, Wilson S

    2009-06-01

    When searching for a known target in a natural texture, practiced humans achieve near-optimal performance compared to a Bayesian ideal searcher constrained with the human map of target detectability across the visual field [Najemnik, J., & Geisler, W. S. (2005). Optimal eye movement strategies in visual search. Nature, 434, 387-391]. To do so, humans must be good at choosing where to fixate during the search [Najemnik, J., & Geisler, W.S. (2008). Eye movement statistics in humans are consistent with an optimal strategy. Journal of Vision, 8(3), 1-14. 4]; however, it seems unlikely that a biological nervous system would implement the computations for the Bayesian ideal fixation selection because of their complexity. Here we derive and test a simple heuristic for optimal fixation selection that appears to be a much better candidate for implementation within a biological nervous system. Specifically, we show that the near-optimal fixation location is the maximum of the current posterior probability distribution for target location after the distribution is filtered by (convolved with) the square of the retinotopic target detectability map. We term the model that uses this strategy the entropy limit minimization (ELM) searcher. We show that when constrained with human-like retinotopic map of target detectability and human search error rates, the ELM searcher performs as well as the Bayesian ideal searcher, and produces fixation statistics similar to human.

  19. 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.

  20. Impact of Supplemental Site Grants to Increase African-American Accrual for SELECT

    PubMed Central

    Cook, Elise D.; Arnold, Kathryn B.; Hermos, John A.; McCaskill-Stevens, Worta; Moody-Thomas, Sarah; Probstfield, Jeffrey L.; Hamilton, Sandra J.; Campbell, Russell D.; Anderson, Karen B.; Minasian, Lori M.

    2014-01-01

    Background Low rates of minority recruitment in prevention studies may reduce the generalizability of study results to minority populations, including African Americans. High African American accrual to prevention studies requires additional resources and focused efforts. Objective To analyze the impact of Minority Recruitment Enhancement Grants (MREGs) on African American recruitment to the Selenium and Vitamin E Cancer Prevention Trial (SELECT). Results Fifteen of 427 SELECT sites received MREGs after they demonstrated early success in minority recruitment. After receiving the grants, the average monthly rate of African American recruitment at these sites increased from 27.2% to 31.5%, and total average monthly recruitment also increased. Sites that did not receive grants, including sites that did not apply, increased average monthly African American recruitment from 11.0% to 14.6% but declined in total average monthly recruitment. Conclusions and Implications Sites who received MREGs modestly increased both the proportion of African American recruits and total recruits. These results are tempered by the high cost of the intervention, the relatively low number of SELECT sites that applied for the grants and the administrative delays in implementation. Nevertheless, targeted grants may be a useful multi-site intervention to increase African American accrual for a prevention study where adequate African American recruitment is essential. PMID:20156960

  1. 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.

  2. U.S. Department of Energy's site screening, site selection, and initial characterization for storage of CO2 in deep geological formations

    USGS Publications Warehouse

    Rodosta, T.D.; Litynski, J.T.; Plasynski, S.I.; Hickman, S.; Frailey, S.; Myer, L.

    2011-01-01

    The U.S. Department of Energy (DOE) is the lead Federal agency for the development and deployment of carbon sequestration technologies. As part of its mission to facilitate technology transfer and develop guidelines from lessons learned, DOE is developing a series of best practice manuals (BPMs) for carbon capture and storage (CCS). The "Site Screening, Site Selection, and Initial Characterization for Storage of CO2 in Deep Geological Formations" BPM is a compilation of best practices and includes flowchart diagrams illustrating the general decision making process for Site Screening, Site Selection, and Initial Characterization. The BPM integrates the knowledge gained from various programmatic efforts, with particular emphasis on the Characterization Phase through pilot-scale CO2 injection testing of the Validation Phase of the Regional Carbon Sequestration Partnership (RCSP) Initiative. Key geologic and surface elements that suitable candidate storage sites should possess are identified, along with example Site Screening, Site Selection, and Initial Characterization protocols for large-scale geologic storage projects located across diverse geologic and regional settings. This manual has been written as a working document, establishing a framework and methodology for proper site selection for CO2 geologic storage. This will be useful for future CO2 emitters, transporters, and storage providers. It will also be of use in informing local, regional, state, and national governmental agencies of best practices in proper sequestration site selection. Furthermore, it will educate the inquisitive general public on options and processes for geologic CO2 storage. In addition to providing best practices, the manual presents a geologic storage resource and capacity classification system. The system provides a "standard" to communicate storage and capacity estimates, uncertainty and project development risk, data guidelines and analyses for adequate site characterization, and

  3. Evolution of Site-Selection Stabilizes Population Dynamics, Promotes Even Distribution of Individuals, and Occasionally Causes Evolutionary Suicide.

    PubMed

    Parvinen, Kalle; Brännström, Åke

    2016-08-01

    Species that compete for access to or use of sites, such as parasitic mites attaching to honey bees or apple maggots laying eggs in fruits, can potentially increase their fitness by carefully selecting sites at which they face little or no competition. Here, we systematically investigate the evolution of site-selection strategies among animals competing for discrete sites. By developing and analyzing a mechanistic and population-dynamical model of site selection in which searching individuals encounter sites sequentially and can choose to accept or continue to search based on how many conspecifics are already there, we give a complete characterization of the different site-selection strategies that can evolve. We find that evolution of site-selection stabilizes population dynamics, promotes even distribution of individuals among sites, and occasionally causes evolutionary suicide. We also discuss the broader implications of our findings and propose how they can be reconciled with an earlier study (Nonaka et al. in J Theor Biol 317:96-104, 2013) that reported selection toward ever higher levels of aggregation among sites as a consequence of site-selection.

  4. Atmospheric Constraints on Landing Site Selection

    NASA Astrophysics Data System (ADS)

    Kass, David M.; Schofield, J. T.

    2001-01-01

    The Martian atmosphere is a significant part of the environment that the Mars Exploration Rovers (MER) will encounter. As such, it imposes important constraints on where the rovers can and cannot land. Unfortunately, as there are no meteorological instruments on the rovers, there is little atmospheric science that can be accomplished, and no scientific preference for landing sites. The atmosphere constrains landing site selection in two main areas, the entry descent and landing (EDL) process and the survivability of the rovers on the surface. EDL is influenced by the density profile and boundary layer winds (up to altitudes of 5 to 10 km). Surface survivability involves atmospheric dust, temperatures and winds. During EDL, the atmosphere is used to slow the lander down, both ballistically and on the parachute. This limits the maximum elevation of the landing site to -1.3 km below the MOLA reference aeroid. The landers need to encounter a sufficiently dense atmosphere to be able to stop, and the deeper the landing site, the more column integrated atmosphere the lander can pass through before reaching the surface. The current limit was determined both by a desire to be able to reach the hematite region and by a set of atmosphere models we developed for EDL simulations. These are based on Thermal Emission Spectrometer (TES) atmospheric profile measurements, Ames Mars General Circulation Model (MGCM) results, and the 1-D Ames GCM radiative/convective model by J. Murphy. The latter is used for the near surface diurnal cycle. The current version of our model encompasses representative latitude bands, but we intend to make specific models for the final candidate landing sites to insure that they fall within the general envelope. The second constraint imposed on potential landing sites through the EDL process is the near surface wind. The wind in the lower approximately 5 km determines the horizontal velocity that the landers have when they land. Due to the mechanics of

  5. Cache-site selection in Clark's Nutcracker (Nucifraga columbiana)

    Treesearch

    Teresa J. Lorenz; Kimberly A. Sullivan; Amanda V. Bakian; Carol A. Aubry

    2011-01-01

    Clark's Nutcracker (Nucifraga Columbiana) is one of the most specialized scatter-hoarding birds, considered a seed disperser for four species of pines (Pinus spp.), as well as an obligate coevolved mutualist of White bark Pine (P. albicaulis). Cache-site selection has not been formally studied in Clark...

  6. Waterbird nest-site selection is influenced by neighboring nests and island topography

    USGS Publications Warehouse

    Hartman, Christopher; Ackerman, Joshua T.; 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

  7. 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.

  8. 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…

  9. 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.

  10. 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.

  11. The Spleen as an Optimal Site for Islet Transplantation and a Source of Mesenchymal Stem Cells.

    PubMed

    Sakata, Naoaki; Yoshimatsu, Gumpei; Kodama, Shohta

    2018-05-07

    This review demonstrates the unique potential of the spleen as an optimal site for islet transplantation and as a source of mesenchymal stem cells. Islet transplantation is a cellular replacement therapy used to treat severe diabetes mellitus; however, its clinical outcome is currently unsatisfactory. Selection of the most appropriate transplantation site is a major factor affecting the clinical success of this therapy. The spleen has long been studied as a candidate site for islet transplantation. Its advantages include physiological insulin drainage and regulation of immunity, and it has recently also been shown to contribute to the regeneration of transplanted islets. However, the efficacy of transplantation in the spleen is lower than that of intraportal transplantation, which is the current representative method of clinical islet transplantation. Safer and more effective methods of islet transplantation need to be established to allow the spleen to be used for clinical transplantation. The spleen is also of interest as a mesenchymal stem cell reservoir. Splenic mesenchymal stem cells contribute to the repair of damaged tissue, and their infusion may thus be a promising therapy for autoimmune diseases, including type 1 diabetes mellitus and Sjogren’s syndrome.

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

    PubMed Central

    Nordborg, Magnus; Innan, Hideki

    2003-01-01

    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. PMID:12663556

  13. 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.

  14. Selection on Inversion Breakpoints Favors Proximity to Pairing Sensitive Sites in Drosophila melanogaster

    PubMed Central

    Corbett-Detig, Russell B.

    2016-01-01

    Chromosomal inversions are widespread among taxa, and have been implicated in a number of biological processes including adaptation, sex chromosome evolution, and segregation distortion. Consistent with selection favoring linkage between loci, it is well established that length is a selected trait of inversions. However, the factors that affect the distribution of inversion breakpoints remain poorly understood. “Sensitive sites” have been mapped on all euchromatic chromosome arms in Drosophila melanogaster, and may be a source of natural selection on inversion breakpoint positions. Briefly, sensitive sites are genomic regions wherein proximal structural rearrangements result in large reductions in local recombination rates in heterozygotes. Here, I show that breakpoints of common inversions are significantly more likely to lie within a cytological band containing a sensitive site than are breakpoints of rare inversions. Furthermore, common inversions for which neither breakpoint intersects a sensitive site are significantly longer than rare inversions, but common inversions whose breakpoints intersect a sensitive site show no evidence for increased length. I interpret these results to mean that selection favors inversions whose breakpoints disrupt synteny near to sensitive sites, possibly because these inversions suppress recombination in large genomic regions. To my knowledge this is the first evidence consistent with positive selection acting on inversion breakpoint positions. PMID:27343234

  15. Improving site selection in clinical studies: a standardised, objective, multistep method and first experience results.

    PubMed

    Hurtado-Chong, Anahí; Joeris, Alexander; Hess, Denise; Blauth, Michael

    2017-07-12

    A considerable number of clinical studies experience delays, which result in increased duration and costs. In multicentre studies, patient recruitment is among the leading causes of delays. Poor site selection can result in low recruitment and bad data quality. Site selection is therefore crucial for study quality and completion, but currently no specific guidelines are available. Selection of sites adequate to participate in a prospective multicentre cohort study was performed through an open call using a newly developed objective multistep approach. The method is based on use of a network, definition of objective criteria and a systematic screening process. Out of 266 interested sites, 24 were shortlisted and finally 12 sites were selected to participate in the study. The steps in the process included an open call through a network, use of selection questionnaires tailored to the study, evaluation of responses using objective criteria and scripted telephone interviews. At each step, the number of candidate sites was quickly reduced leaving only the most promising candidates. Recruitment and quality of data went according to expectations in spite of the contracting problems faced with some sites. The results of our first experience with a standardised and objective method of site selection are encouraging. The site selection method described here can serve as a guideline for other researchers performing multicentre studies. ClinicalTrials.gov: NCT02297581. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  16. WFIRST: Exoplanet Target Selection and Scheduling with Greedy Optimization

    NASA Astrophysics Data System (ADS)

    Keithly, Dean; Garrett, Daniel; Delacroix, Christian; Savransky, Dmitry

    2018-01-01

    We present target selection and scheduling algorithms for missions with direct imaging of exoplanets, and the Wide Field Infrared Survey Telescope (WFIRST) in particular, which will be equipped with a coronagraphic instrument (CGI). Optimal scheduling of CGI targets can maximize the expected value of directly imaged exoplanets (completeness). Using target completeness as a reward metric and integration time plus overhead time as a cost metric, we can maximize the sum completeness for a mission with a fixed duration. We optimize over these metrics to create a list of target stars using a greedy optimization algorithm based off altruistic yield optimization (AYO) under ideal conditions. We simulate full missions using EXOSIMS by observing targets in this list for their predetermined integration times. In this poster, we report the theoretical maximum sum completeness, mean number of detected exoplanets from Monte Carlo simulations, and the ideal expected value of the simulated missions.

  17. 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

  18. 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

  19. Ant-cuckoo colony optimization for feature selection in digital mammogram.

    PubMed

    Jona, J B; Nagaveni, N

    2014-01-15

    Digital mammogram is the only effective screening method to detect the breast cancer. Gray Level Co-occurrence Matrix (GLCM) textural features are extracted from the mammogram. All the features are not essential to detect the mammogram. Therefore identifying the relevant feature is the aim of this work. Feature selection improves the classification rate and accuracy of any classifier. In this study, a new hybrid metaheuristic named Ant-Cuckoo Colony Optimization a hybrid of Ant Colony Optimization (ACO) and Cuckoo Search (CS) is proposed for feature selection in Digital Mammogram. ACO is a good metaheuristic optimization technique but the drawback of this algorithm is that the ant will walk through the path where the pheromone density is high which makes the whole process slow hence CS is employed to carry out the local search of ACO. Support Vector Machine (SVM) classifier with Radial Basis Kernal Function (RBF) is done along with the ACO to classify the normal mammogram from the abnormal mammogram. Experiments are conducted in miniMIAS database. The performance of the new hybrid algorithm is compared with the ACO and PSO algorithm. The results show that the hybrid Ant-Cuckoo Colony Optimization algorithm is more accurate than the other techniques.

  20. 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.

  1. Pilot Project to Optimize Superfund-financed Pump and Treat Systems: Summary Report and Lessons Learned

    EPA Pesticide Factsheets

    This report summarizes Phase II (site optimization) of the Nationwide Fund-lead Pump and Treat Optimization Project. This phase included conducting Remediation System Evaluations (RSEs) at each of the 20 sites selected in Phase I.

  2. Site-selective XAFS spectroscopy tuned to surface active sites of Cu/ZnO and Cr/SiO2 catalysts.

    PubMed

    Izumi, Y; Nagamori, H; Kiyotaki, F; Minato, T

    2001-03-01

    XAFS (X-ray absorption fine structure) spectra were measured by using the fluorescence spectrometer for the emitted X-ray from sample. The chemical shifts between Cu0 and Cu1 and between CrIII and CrVI were evaluated. Tuning the fluorescence spectrometer to each energy, the Cu0 and CuI site-selective XANES for Cu/ZnO catalyst were measured. The first one was similar to the XANES of Cu metal and the second one was the 5 : 5 average of XANES for CuI sites + Cu metal. The population ratio of copper site of the Cu/ZnO catalyst was found to be Cu metal: Cu2O : CuI atomically dispersed on surface = 70(+/-23) : 22(+/-14) : 8(+/-5). Site-selective XANES for CrIII site of Cr/SiO2 catalyst was also studied.

  3. Control of Ion Selectivity in LeuT: Two Na+ Binding Sites with two different mechanisms

    PubMed Central

    Noskov, Sergei Y.; Roux, Benoît

    2016-01-01

    The x-ray structure of LeuT, a bacterial homologue of Na+/Cl−-dependent neurotransmitter transporter, 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 site 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 site 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 poly-peptide chain surrounding the ion according to a snug-fit mechanism. PMID:18280500

  4. 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.

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

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

    Derebe, Mehabaw G.; Sauer, David B.; Zeng, Weizhong

    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 themore » 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.« less

  6. Centuries of domestication has not impaired oviposition site-selection function in the silkmoth, Bombyx mori

    PubMed Central

    Damodaram, Kamala Jayanthi Pagadala; Kempraj, Vivek; Aurade, Ravindra Mahadappa; Rajasekhar, Sowmya Bandhisara; Venkataramanappa, Ravindra Kothapalli; Nandagopal, Bakthavatsalam; Verghese, Abraham

    2014-01-01

    Oviposition site-selection in insects is mediated through innate recognition templates (IRTs) tuned to specific chemical cues. These cues aid gravid insects in choosing suitable oviposition sites and may even enhance the fitness of their offspring by warding off predators and parasitoids. However, studies on the evolution of oviposition site-selection and cues instigating oviposition in domesticated insects remain elusive. Using the interaction between the silkmoth, Bombyx mori, and its host plant mulberry, Morus alba, as a model system, we demonstrate that centuries of domestication of silkmoth has not impaired its oviposition site-selection function. Silkmoths significantly preferred mulberry leaves to filter paper as oviposition sites. Oviposition assays with filter paper, filter paper treated with leaf volatiles and leaf alone proved that surface texture was not a significant criterion for oviposition site-selection, but volatile cues were. Oviposition assays with electrophysiologically active compounds from mulberry revealed that two of the volatiles, valencene and α-humulene, aided moths in choosing suitable oviposition sites and enhanced egg-laying significantly. Moreover, we show that generalist egg-parasitoids are strongly repelled by valencene and α-humulene. Our results demonstrate that IRTs tuned to cues that aid crucial functions like oviposition site-selection are less likely to be impaired even after centuries of domestication. PMID:25503440

  7. Stability of choice in the honey bee nest-site selection process.

    PubMed

    Nevai, Andrew L; Passino, Kevin M; Srinivasan, Parthasarathy

    2010-03-07

    We introduce a pair of compartment models for the honey bee nest-site selection process that lend themselves to analytic methods. The first model represents a swarm of bees deciding whether a site is viable, and the second characterizes its ability to select between two viable sites. We find that the one-site assessment process has two equilibrium states: a disinterested equilibrium (DE) in which the bees show no interest in the site and an interested equilibrium (IE) in which bees show interest. In analogy with epidemic models, we define basic and absolute recruitment numbers (R(0) and B(0)) as measures of the swarm's sensitivity to dancing by a single bee. If R(0) is less than one then the DE is locally stable, and if B(0) is less than one then it is globally stable. If R(0) is greater than one then the DE is unstable and the IE is stable under realistic conditions. In addition, there exists a critical site quality threshold Q(*) above which the site can attract some interest (at equilibrium) and below which it cannot. We also find the existence of a second critical site quality threshold Q(**) above which the site can attract a quorum (at equilibrium) and below which it cannot. The two-site discrimination process, in which we examine a swarm's ability to simultaneously consider two sites differing in both site quality and discovery time, has a stable DE if and only if both sites' individual basic recruitment numbers are less than one. Numerical experiments are performed to study the influences of site quality on quorum time and the outcome of competition between a lower quality site discovered first and a higher quality site discovered second. 2009 Elsevier Ltd. All rights reserved.

  8. Toward optimal feature and time segment selection by divergence method for EEG signals classification.

    PubMed

    Wang, Jie; Feng, Zuren; Lu, Na; Luo, Jing

    2018-06-01

    Feature selection plays an important role in the field of EEG signals based motor imagery pattern classification. It is a process that aims to select an optimal feature subset from the original set. Two significant advantages involved are: lowering the computational burden so as to speed up the learning procedure and removing redundant and irrelevant features so as to improve the classification performance. Therefore, feature selection is widely employed in the classification of EEG signals in practical brain-computer interface systems. In this paper, we present a novel statistical model to select the optimal feature subset based on the Kullback-Leibler divergence measure, and automatically select the optimal subject-specific time segment. The proposed method comprises four successive stages: a broad frequency band filtering and common spatial pattern enhancement as preprocessing, features extraction by autoregressive model and log-variance, the Kullback-Leibler divergence based optimal feature and time segment selection and linear discriminate analysis classification. More importantly, this paper provides a potential framework for combining other feature extraction models and classification algorithms with the proposed method for EEG signals classification. Experiments on single-trial EEG signals from two public competition datasets not only demonstrate that the proposed method is effective in selecting discriminative features and time segment, but also show that the proposed method yields relatively better classification results in comparison with other competitive methods. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Training set optimization under population structure in genomic selection

    USDA-ARS?s Scientific Manuscript database

    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...

  10. Elk resource selection at parturition sites, Black Hills, South Dakota

    Treesearch

    Chadwick P. Lehman; Mark A. Rumble; Christopher T. Rota; Benjamin J. Bird; Dillon T. Fogarty; Joshua J. Millspaugh

    2015-01-01

    We studied elk (Cervus canadensis nelsoni) parturition sites at coarse (314-km2 and 7-km2) and fine (0.2-ha) scales in the Black Hills, South Dakota, 2011-2013, following a period of population decline and poor calf recruitment. Our objective was to test whether female elk selected parturition sites across spatial scales in association with forage, terrain...

  11. Transshipment site selection using the AHP and TOPSIS approaches under fuzzy environment.

    PubMed

    Onüt, Semih; Soner, Selin

    2008-01-01

    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.

  12. 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

  13. 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 Selection...

  14. 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 Selection...

  15. 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 Selection...

  16. A multi-objective model for closed-loop supply chain optimization and efficient supplier selection in a competitive environment considering quantity discount policy

    NASA Astrophysics Data System (ADS)

    Jahangoshai Rezaee, Mustafa; Yousefi, Samuel; Hayati, Jamileh

    2017-06-01

    Supplier selection and allocation of optimal order quantity are two of the most important processes in closed-loop supply chain (CLSC) and reverse logistic (RL). So that providing high quality raw material is considered as a basic requirement for a manufacturer to produce popular products, as well as achieve more market shares. On the other hand, considering the existence of competitive environment, suppliers have to offer customers incentives like discounts and enhance the quality of their products in a competition with other manufacturers. Therefore, in this study, a model is presented for CLSC optimization, efficient supplier selection, as well as orders allocation considering quantity discount policy. It is modeled using multi-objective programming based on the integrated simultaneous data envelopment analysis-Nash bargaining game. In this study, maximizing profit and efficiency and minimizing defective and functions of delivery delay rate are taken into accounts. Beside supplier selection, the suggested model selects refurbishing sites, as well as determining the number of products and parts in each network's sector. The suggested model's solution is carried out using global criteria method. Furthermore, based on related studies, a numerical example is examined to validate it.

  17. California heavy duty truck travel survey on selected sites.

    DOT National Transportation Integrated Search

    2001-12-01

    The overall goal of the Heavy Duty Truck Travel (HDT) Survey was to collect representative truck travel data for selected sites in California. An integral aspect of the project was a literature search and inventory study of freight data survey collec...

  18. Analysis of Multi-Criteria Evaluation Method of Landfill Site Selection for Municipal Solid Waste Management

    NASA Astrophysics Data System (ADS)

    Mohammed, Habiba Ibrahim; Majid, Zulkepli; Yusof, Norhakim Bin; Bello Yamusa, Yamusa

    2018-03-01

    Landfilling remains the most common systematic technique of solid waste disposal in most of the developed and developing countries. Finding a suitable site for landfill is a very challenging task. Landfill site selection process aims to provide suitable areas that will protect the environment and public health from pollution and hazards. Therefore, various factors such as environmental, physical, socio-economic, and geological criteria must be considered before siting any landfill. This makes the site selection process vigorous and tedious because it involves the processing of large amount of spatial data, rules and regulations from different agencies and also policy from decision makers. This allows the incorporation of conflicting objectives and decision maker preferences into spatial decision models. This paper particularly analyzes the multi-criteria evaluation (MCE) method of landfill site selection for solid waste management by means of literature reviews and surveys. The study will help the decision makers and waste management authorities to choose the most effective method when considering landfill site selection.

  19. Pipe degradation investigations for optimization of flow-accelerated corrosion inspection location selection

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

    Chandra, S.; Habicht, P.; Chexal, B.

    1995-12-01

    A large amount of piping in a typical nuclear power plant is susceptible to Flow-Accelerated Corrosion (FAC) wall thinning to varying degrees. A typical PAC monitoring program includes the wall thickness measurement of a select number of components in order to judge the structural integrity of entire systems. In order to appropriately allocate resources and maintain an adequate FAC program, it is necessary to optimize the selection of components for inspection by focusing on those components which provide the best indication of system susceptibility to FAC. A better understanding of system FAC predictability and the types of FAC damage encounteredmore » can provide some of the insight needed to better focus and optimize the inspection plan for an upcoming refueling outage. Laboratory examination of FAC damaged components removed from service at Northeast Utilities` (NU) nuclear power plants provides a better understanding of the damage mechanisms involved and contributing causes. Selected results of this ongoing study are presented with specific conclusions which will help NU to better focus inspections and thus optimize the ongoing FAC inspection program.« less

  20. 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.

  1. Mode selective generation of guided waves by systematic optimization of the interfacial shear stress profile

    NASA Astrophysics Data System (ADS)

    Yazdanpanah Moghadam, Peyman; Quaegebeur, Nicolas; Masson, Patrice

    2015-01-01

    Piezoelectric transducers are commonly used in structural health monitoring systems to generate and measure ultrasonic guided waves (GWs) by applying interfacial shear and normal stresses to the host structure. In most cases, in order to perform damage detection, advanced signal processing techniques are required, since a minimum of two dispersive modes are propagating in the host structure. In this paper, a systematic approach for mode selection is proposed by optimizing the interfacial shear stress profile applied to the host structure, representing the first step of a global optimization of selective mode actuator design. This approach has the potential of reducing the complexity of signal processing tools as the number of propagating modes could be reduced. Using the superposition principle, an analytical method is first developed for GWs excitation by a finite number of uniform segments, each contributing with a given elementary shear stress profile. Based on this, cost functions are defined in order to minimize the undesired modes and amplify the selected mode and the optimization problem is solved with a parallel genetic algorithm optimization framework. Advantages of this method over more conventional transducers tuning approaches are that (1) the shear stress can be explicitly optimized to both excite one mode and suppress other undesired modes, (2) the size of the excitation area is not constrained and mode-selective excitation is still possible even if excitation width is smaller than all excited wavelengths, and (3) the selectivity is increased and the bandwidth extended. The complexity of the optimal shear stress profile obtained is shown considering two cost functions with various optimal excitation widths and number of segments. Results illustrate that the desired mode (A0 or S0) can be excited dominantly over other modes up to a wave power ratio of 1010 using an optimal shear stress profile.

  2. Minimal invasive epicardial lead implantation: optimizing cardiac resynchronization with a new mapping device for epicardial lead placement.

    PubMed

    Maessen, J G; Phelps, B; Dekker, A L A J; Dijkman, B

    2004-05-01

    To optimize resynchronization in biventricular pacing with epicardial leads, mapping to determine the best pacing site, is a prerequisite. A port access surgical mapping technique was developed that allowed multiple pace site selection and reproducible lead evaluation and implantation. Pressure-volume loops analysis was used for real time guidance in targeting epicardial lead placement. Even the smallest changes in lead position revealed significantly different functional results. Optimizing the pacing site with this technique allowed functional improvement up to 40% versus random pace site selection.

  3. Selecting and optimizing eco-physiological parameters of Biome-BGC to reproduce observed woody and leaf biomass growth of Eucommia ulmoides plantation in China using Dakota optimizer

    NASA Astrophysics Data System (ADS)

    Miyauchi, T.; Machimura, T.

    2013-12-01

    In the simulation using an ecosystem process model, the adjustment of parameters is indispensable for improving the accuracy of prediction. This procedure, however, requires much time and effort for approaching the simulation results to the measurements on models consisting of various ecosystem processes. In this study, we tried to apply a general purpose optimization tool in the parameter optimization of an ecosystem model, and examined its validity by comparing the simulated and measured biomass growth of a woody plantation. A biometric survey of tree biomass growth was performed in 2009 in an 11-year old Eucommia ulmoides plantation in Henan Province, China. Climate of the site was dry temperate. Leaf, above- and below-ground woody biomass were measured from three cut trees and converted into carbon mass per area by measured carbon contents and stem density. Yearly woody biomass growth of the plantation was calculated according to allometric relationships determined by tree ring analysis of seven cut trees. We used Biome-BGC (Thornton, 2002) to reproduce biomass growth of the plantation. Air temperature and humidity from 1981 to 2010 was used as input climate condition. The plant functional type was deciduous broadleaf, and non-optimizing parameters were left default. 11-year long normal simulations were performed following a spin-up run. In order to select optimizing parameters, we analyzed the sensitivity of leaf, above- and below-ground woody biomass to eco-physiological parameters. Following the selection, optimization of parameters was performed by using the Dakota optimizer. Dakota is an optimizer developed by Sandia National Laboratories for providing a systematic and rapid means to obtain optimal designs using simulation based models. As the object function, we calculated the sum of relative errors between simulated and measured leaf, above- and below-ground woody carbon at each of eleven years. In an alternative run, errors at the last year (at the

  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. Stationary-phase optimized selectivity liquid chromatography: development of a linear gradient prediction algorithm.

    PubMed

    De Beer, Maarten; Lynen, Fréderic; Chen, Kai; Ferguson, Paul; Hanna-Brown, Melissa; Sandra, Pat

    2010-03-01

    Stationary-phase optimized selectivity liquid chromatography (SOS-LC) is a tool in reversed-phase LC (RP-LC) to optimize the selectivity for a given separation by combining stationary phases in a multisegment column. The presently (commercially) available SOS-LC optimization procedure and algorithm are only applicable to isocratic analyses. Step gradient SOS-LC has been developed, but this is still not very elegant for the analysis of complex mixtures composed of components covering a broad hydrophobicity range. A linear gradient prediction algorithm has been developed allowing one to apply SOS-LC as a generic RP-LC optimization method. The algorithm allows operation in isocratic, stepwise, and linear gradient run modes. The features of SOS-LC in the linear gradient mode are demonstrated by means of a mixture of 13 steroids, whereby baseline separation is predicted and experimentally demonstrated.

  6. Optimal Portfolio Selection Under Concave Price Impact

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

    Ma Jin, E-mail: jinma@usc.edu; Song Qingshuo, E-mail: songe.qingshuo@cityu.edu.hk; Xu Jing, E-mail: xujing8023@yahoo.com.cn

    2013-06-15

    In this paper we study an optimal portfolio selection problem under instantaneous price impact. Based on some empirical analysis in the literature, we model such impact as a concave function of the trading size when the trading size is small. The price impact can be thought of as either a liquidity cost or a transaction cost, but the concavity nature of the cost leads to some fundamental difference from those in the existing literature. We show that the problem can be reduced to an impulse control problem, but without fixed cost, and that the value function is a viscosity solutionmore » to a special type of Quasi-Variational Inequality (QVI). We also prove directly (without using the solution to the QVI) that the optimal strategy exists and more importantly, despite the absence of a fixed cost, it is still in a 'piecewise constant' form, reflecting a more practical perspective.« less

  7. Soil attributes drive nest-site selection by the campo miner Geositta poeciloptera.

    PubMed

    Meireles, Ricardo Camargos de; Teixeira, João Paulo Gusmão; Solar, Ricardo; Vasconcelos, Bruno Nery F; Fernandes, Raphael B A; Lopes, Leonardo Esteves

    2018-01-01

    Substrate type is a key-factor in nest-site selection and nest architecture of burrowing birds. However, little is known about which factors drive nest-site selection for these species, especially in the tropics. We studied the influence of soil attributes on nest-site selection by the campo miner Geositta poeciloptera, an open grassland bird that builds its nests within soil cavities. For all nests found, we measured the depth of the nest cavity and the resistance of the soil to penetration, and identified the soil horizon in which the nest was located. In soil banks with nests, we collected soil samples for granulometric analysis around each nest cavity, while in soil banks without nests we collected these samples at random points. From 43 nests found, 86% were located in the deeper soil horizons (C-horizon), and only 14% in the shallower horizons (B-horizon). Granulometric analysis showed that the C-horizons possessed a high similar granulometric composition, with high silt and low clay contents. These characteristics are associated with a low degree of structural development of the soil, which makes it easier to excavate. Contrarily, soil resistance to penetration does not seem to be an important criterion for nest site selection, although nests in more resistant the soils tend to have shallower nest cavities. Among the soil banks analyzed, 40% of those without cavities possessed a larger proportion of B-horizon relative to the C-horizon, and their texture was more clayey. On the other hand, almost all soil banks containing nest cavities had a larger C-horizon and a silty texture, indicating that soil attributes drive nest-site selection by G. poeciloptera. Thus, we conclude that the patchy distribution of G. poeciloptera can attributed to the infrequent natural exposure of the C-horizon in the tropical region, where well developed, deep and permeable soils are more common.

  8. Soil attributes drive nest-site selection by the campo miner Geositta poeciloptera

    PubMed Central

    Teixeira, João Paulo Gusmão; Solar, Ricardo; Vasconcelos, Bruno Nery F.; Fernandes, Raphael B. A.; Lopes, Leonardo Esteves

    2018-01-01

    Substrate type is a key-factor in nest-site selection and nest architecture of burrowing birds. However, little is known about which factors drive nest-site selection for these species, especially in the tropics. We studied the influence of soil attributes on nest-site selection by the campo miner Geositta poeciloptera, an open grassland bird that builds its nests within soil cavities. For all nests found, we measured the depth of the nest cavity and the resistance of the soil to penetration, and identified the soil horizon in which the nest was located. In soil banks with nests, we collected soil samples for granulometric analysis around each nest cavity, while in soil banks without nests we collected these samples at random points. From 43 nests found, 86% were located in the deeper soil horizons (C-horizon), and only 14% in the shallower horizons (B-horizon). Granulometric analysis showed that the C-horizons possessed a high similar granulometric composition, with high silt and low clay contents. These characteristics are associated with a low degree of structural development of the soil, which makes it easier to excavate. Contrarily, soil resistance to penetration does not seem to be an important criterion for nest site selection, although nests in more resistant the soils tend to have shallower nest cavities. Among the soil banks analyzed, 40% of those without cavities possessed a larger proportion of B-horizon relative to the C-horizon, and their texture was more clayey. On the other hand, almost all soil banks containing nest cavities had a larger C-horizon and a silty texture, indicating that soil attributes drive nest-site selection by G. poeciloptera. Thus, we conclude that the patchy distribution of G. poeciloptera can attributed to the infrequent natural exposure of the C-horizon in the tropical region, where well developed, deep and permeable soils are more common. PMID:29381768

  9. Retirement investment theory explains patterns in songbird nest-site choice

    USGS Publications Warehouse

    Streby, Henry M.; Refsnider, Jeanine M.; Peterson, Sean M.; Andersen, David E.

    2014-01-01

    When opposing evolutionary selection pressures act on a behavioural trait, the result is often stabilizing selection for an intermediate optimal phenotype, with deviations from the predicted optimum attributed to tracking a moving target, development of behavioural syndromes or shifts in riskiness over an individual's lifetime. We investigated nest-site choice by female golden-winged warblers, and the selection pressures acting on that choice by two fitness components, nest success and fledgling survival. We observed strong and consistent opposing selection pressures on nest-site choice for maximizing these two fitness components, and an abrupt, within-season switch in the fitness component birds prioritize via nest-site choice, dependent on the time remaining for additional nesting attempts. We found that females consistently deviated from the predicted optimal behaviour when choosing nest sites because they can make multiple attempts at one fitness component, nest success, but only one attempt at the subsequent component, fledgling survival. Our results demonstrate a unique natural strategy for balancing opposing selection pressures to maximize total fitness. This time-dependent switch from high to low risk tolerance in nest-site choice maximizes songbird fitness in the same way a well-timed switch in human investor risk tolerance can maximize one's nest egg at retirement. Our results also provide strong evidence for the adaptive nature of songbird nest-site choice, which we suggest has been elusive primarily due to a lack of consideration for fledgling survival.

  10. Retirement investment theory explains patterns in songbird nest-site choice

    PubMed Central

    Streby, Henry M.; Refsnider, Jeanine M.; Peterson, Sean M.; Andersen, David E.

    2014-01-01

    When opposing evolutionary selection pressures act on a behavioural trait, the result is often stabilizing selection for an intermediate optimal phenotype, with deviations from the predicted optimum attributed to tracking a moving target, development of behavioural syndromes or shifts in riskiness over an individual's lifetime. We investigated nest-site choice by female golden-winged warblers, and the selection pressures acting on that choice by two fitness components, nest success and fledgling survival. We observed strong and consistent opposing selection pressures on nest-site choice for maximizing these two fitness components, and an abrupt, within-season switch in the fitness component birds prioritize via nest-site choice, dependent on the time remaining for additional nesting attempts. We found that females consistently deviated from the predicted optimal behaviour when choosing nest sites because they can make multiple attempts at one fitness component, nest success, but only one attempt at the subsequent component, fledgling survival. Our results demonstrate a unique natural strategy for balancing opposing selection pressures to maximize total fitness. This time-dependent switch from high to low risk tolerance in nest-site choice maximizes songbird fitness in the same way a well-timed switch in human investor risk tolerance can maximize one's nest egg at retirement. Our results also provide strong evidence for the adaptive nature of songbird nest-site choice, which we suggest has been elusive primarily due to a lack of consideration for fledgling survival. PMID:24403320

  11. 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

  12. 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.

  13. 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

  14. 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.

  15. Temporary site selection and decision-making methods: a case study of Tehran, Iran.

    PubMed

    Omidvar, Babak; Baradaran-Shoraka, Mohammad; Nojavan, Mehdi

    2013-07-01

    Decisions on selecting an appropriate site for temporary shelter used to be taken in a limited amount of time after a disaster. The need for a systematic method in this area inspired the MADM (multi-attribute decision making) for complex disaster management decisions. This research proposes a model for appropriate and systematic site selection for temporary shelters, before an earthquake, using a geographical information system and MADM based on an earthquake damage assessment. After the effective criteria for site selection of temporary shelters are determined, the geographical layers of these criteria are prepared for Municipal District No.1 of Greater Tehran, the capital of Iran. Given these attributes and the required shelter area (415-610 hectares), 14 zones are proposed initially. Various MADM methods are used for the final selection. The mean of the aggregated ranking results are determined, and 10 of the 14 initial zones are ranked. © 2013 The Author(s). Journal compilation © Overseas Development Institute, 2013.

  16. 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

  17. 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. © The Author(s) 2016.

  18. Optimal environmental management strategy and implementation for groundwater contamination prevention and restoration.

    PubMed

    Wang, Mingyu

    2006-04-01

    An innovative management strategy is proposed for optimized and integrated environmental management for regional or national groundwater contamination prevention and restoration allied with consideration of sustainable development. This management strategy accounts for availability of limited resources, human health and ecological risks from groundwater contamination, costs for groundwater protection measures, beneficial uses and values from groundwater protection, and sustainable development. Six different categories of costs are identified with regard to groundwater prevention and restoration. In addition, different environmental impacts from groundwater contamination including human health and ecological risks are individually taken into account. System optimization principles are implemented to accomplish decision-makings on the optimal resources allocations of the available resources or budgets to different existing contaminated sites and projected contamination sites for a maximal risk reduction. Established management constraints such as budget limitations under different categories of costs are satisfied at the optimal solution. A stepwise optimization process is proposed in which the first step is to select optimally a limited number of sites where remediation or prevention measures will be taken, from all the existing contaminated and projected contamination sites, based on a total regionally or nationally available budget in a certain time frame such as 10 years. Then, several optimization steps determined year-by-year optimal distributions of the available yearly budgets for those selected sites. A hypothetical case study is presented to demonstrate a practical implementation of the management strategy. Several issues pertaining to groundwater contamination exposure and risk assessments and remediation cost evaluations are briefly discussed for adequately understanding implementations of the management strategy.

  19. Simulation Experiment on Landing Site Selection Using a Simple Geometric Approach

    NASA Astrophysics Data System (ADS)

    Zhao, W.; Tong, X.; Xie, H.; Jin, Y.; Liu, S.; Wu, D.; Liu, X.; Guo, L.; Zhou, Q.

    2017-07-01

    Safe landing is an important part of the planetary exploration mission. Even fine scale terrain hazards (such as rocks, small craters, steep slopes, which would not be accurately detected from orbital reconnaissance) could also pose a serious risk on planetary lander or rover and scientific instruments on-board it. In this paper, a simple geometric approach on planetary landing hazard detection and safe landing site selection is proposed. In order to achieve full implementation of this algorithm, two easy-to-compute metrics are presented for extracting the terrain slope and roughness information. Unlike conventional methods which must do the robust plane fitting and elevation interpolation for DEM generation, in this work, hazards is identified through the processing directly on LiDAR point cloud. For safe landing site selection, a Generalized Voronoi Diagram is constructed. Based on the idea of maximum empty circle, the safest landing site can be determined. In this algorithm, hazards are treated as general polygons, without special simplification (e.g. regarding hazards as discrete circles or ellipses). So using the aforementioned method to process hazards is more conforming to the real planetary exploration scenario. For validating the approach mentioned above, a simulated planetary terrain model was constructed using volcanic ash with rocks in indoor environment. A commercial laser scanner mounted on a rail was used to scan the terrain surface at different hanging positions. The results demonstrate that fairly hazard detection capability and reasonable site selection was obtained compared with conventional method, yet less computational time and less memory usage was consumed. Hence, it is a feasible candidate approach for future precision landing selection on planetary surface.

  20. Mathematical Optimization Algorithm for Minimizing the Cost Function of GHG Emission in AS/RS Using Positive Selection Based Clonal Selection Principle

    NASA Astrophysics Data System (ADS)

    Mahalakshmi; Murugesan, R.

    2018-04-01

    This paper regards with the minimization of total cost of Greenhouse Gas (GHG) efficiency in Automated Storage and Retrieval System (AS/RS). A mathematical model is constructed based on tax cost, penalty cost and discount cost of GHG emission of AS/RS. A two stage algorithm namely positive selection based clonal selection principle (PSBCSP) is used to find the optimal solution of the constructed model. In the first stage positive selection principle is used to reduce the search space of the optimal solution by fixing a threshold value. In the later stage clonal selection principle is used to generate best solutions. The obtained results are compared with other existing algorithms in the literature, which shows that the proposed algorithm yields a better result compared to others.

  1. Age trends of genetic parameters, early selection and family by site interactions for growth traits in Larix kaempferi open-pollinated families.

    PubMed

    Diao, Shu; Hou, Yimei; Xie, Yunhui; Sun, Xiaomei

    2016-07-07

    Japanese larch (Larix kaempferi) as a successful exotic species has become one of the most important economic and ecological conifers in China. In order to broaden the genetic resource of Larix kaempferi, an effort was made in 1996 to introduce 128 families from seven seed orchards in Japan, with which to establish two progeny trials in climatically different environments. The experiment was aimed to determine the strategy of early selection, particularly important for long-rotated Japanese larch, and the optimal breeding program for specific environments. Growth trajectories revealed different growth performances of stem height (HGT) and diameter at breast height (DBH) in two different environments, Hubei and Liaoning. In both sites, there were marked variabilities in HGT, DBH and volume (VOL) among families at each year. The trends of individual and family heritability and age-age correlations were found to follow a certain dynamic pattern. Based on these trends, the optimum selection age was determined at four years for HGT and five years for DBH in Hubei and Liaoning. Genetic gains for VOL were 34.4 and 6.04 % in Hubei and Liaoning respectively when selection ratio was 10 % at age 16. Type-B correlations were less than 0.67 and rank correlations of breeding value were less than 0.4 for HGT, DBH and VOL between the two sites, revealing that there exist pronounced family-by-site interactions for the growth traits of Larix kaempferi. Early selection for Larix kaempferi is an effective strategy to overcome its long rotation age. In early selection, dual growth trait selection is more effective than single one. Regionalization deployment should be considered in Larix. kaempferi breeding program based on different environmental factors.

  2. Joint Optimization of Receiver Placement and Illuminator Selection for a Multiband Passive Radar Network.

    PubMed

    Xie, Rui; Wan, Xianrong; Hong, Sheng; Yi, Jianxin

    2017-06-14

    The performance of a passive radar network can be greatly improved by an optimal radar network structure. Generally, radar network structure optimization consists of two aspects, namely the placement of receivers in suitable places and selection of appropriate illuminators. The present study investigates issues concerning the joint optimization of receiver placement and illuminator selection for a passive radar network. Firstly, the required radar cross section (RCS) for target detection is chosen as the performance metric, and the joint optimization model boils down to the partition p -center problem (PPCP). The PPCP is then solved by a proposed bisection algorithm. The key of the bisection algorithm lies in solving the partition set covering problem (PSCP), which can be solved by a hybrid algorithm developed by coupling the convex optimization with the greedy dropping algorithm. In the end, the performance of the proposed algorithm is validated via numerical simulations.

  3. OPTIMAL TIME-SERIES SELECTION OF QUASARS

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

    Butler, Nathaniel R.; Bloom, Joshua S.

    2011-03-15

    We present a novel method for the optimal selection of quasars using time-series observations in a single photometric bandpass. Utilizing the damped random walk model of Kelly et al., we parameterize the ensemble quasar structure function in Sloan Stripe 82 as a function of observed brightness. The ensemble model fit can then be evaluated rigorously for and calibrated with individual light curves with no parameter fitting. This yields a classification in two statistics-one describing the fit confidence and the other describing the probability of a false alarm-which can be tuned, a priori, to achieve high quasar detection fractions (99% completenessmore » with default cuts), given an acceptable rate of false alarms. We establish the typical rate of false alarms due to known variable stars as {approx}<3% (high purity). Applying the classification, we increase the sample of potential quasars relative to those known in Stripe 82 by as much as 29%, and by nearly a factor of two in the redshift range 2.5 < z < 3, where selection by color is extremely inefficient. This represents 1875 new quasars in a 290 deg{sup 2} field. The observed rates of both quasars and stars agree well with the model predictions, with >99% of quasars exhibiting the expected variability profile. We discuss the utility of the method at high redshift and in the regime of noisy and sparse data. Our time-series selection complements well-independent selection based on quasar colors and has strong potential for identifying high-redshift quasars for Baryon Acoustic Oscillations and other cosmology studies in the LSST era.« less

  4. Energy optimization system

    DOEpatents

    Zhou, Zhi; de Bedout, Juan Manuel; Kern, John Michael; Biyik, Emrah; Chandra, Ramu Sharat

    2013-01-22

    A system for optimizing customer utility usage in a utility network of customer sites, each having one or more utility devices, where customer site is communicated between each of the customer sites and an optimization server having software for optimizing customer utility usage over one or more networks, including private and public networks. A customer site model for each of the customer sites is generated based upon the customer site information, and the customer utility usage is optimized based upon the customer site information and the customer site model. The optimization server can be hosted by an external source or within the customer site. In addition, the optimization processing can be partitioned between the customer site and an external source.

  5. High resolution x-ray fluorescence spectroscopy - a new technique for site- and spin-selectivity

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

    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). Themore » 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.« less

  6. 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

  7. Application of geographical information system in disposal site selection for hazardous wastes.

    PubMed

    Rezaeimahmoudi, Mehdi; Esmaeli, Abdolreza; Gharegozlu, Alireza; Shabanian, Hassan; Rokni, Ladan

    2014-01-01

    The aim of this study was to provide a scientific method based on Geographical Information System (GIS) regarding all sustainable development measures to locate a proper landfill for disposal of hazardous wastes, especially industrial (radioactive) wastes. Seven effective factors for determining hazardous waste landfill were applied in Qom Province, central Iran. These criteria included water, slope, population centers, roads, fault, protected areas and geology. The Analysis Hierarchical Process (AHP) model based on pair comparison was used. First, the weight of each factor was determined by experts; afterwards each layer of maps entered to ARC GIS and with special weight multiplied together, finally the best suitable site was introduced. The most suitable sites for burial were in northwest and west of Qom Province and eventually five zones were introduced as the sample sites. GIs and AHP model is introduced as the technical, useful and accelerator tool for disposal site selection. Furthermore it is determined that geological factor is the most effective layer for site selection. It is suggested that geological conditions should be considered primarily then other factors are taken into consideration.

  8. Site quality in Appalachian hardwoods: the biological and economic response under selection silviculture

    Treesearch

    Orris D. McCauley; George R., Jr. Trimble

    1975-01-01

    The relative or percentage value response after 12 years of selective cutting practices on low- and high-quality sites in Appalachian hardwoods amounted to a 119-percent increase on the low-quality site and 145 percent on the high-quality site. The absolute value or actual dollar response, on the other hand, showed that the low-quality site increased in value only $76/...

  9. 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

  10. Siting and sizing of distributed generators based on improved simulated annealing particle swarm optimization.

    PubMed

    Su, Hongsheng

    2017-12-18

    Distributed power grids generally contain multiple diverse types of distributed generators (DGs). Traditional particle swarm optimization (PSO) and simulated annealing PSO (SA-PSO) algorithms have some deficiencies in site selection and capacity determination of DGs, such as slow convergence speed and easily falling into local trap. In this paper, an improved SA-PSO (ISA-PSO) algorithm is proposed by introducing crossover and mutation operators of genetic algorithm (GA) into SA-PSO, so that the capabilities of the algorithm are well embodied in global searching and local exploration. In addition, diverse types of DGs are made equivalent to four types of nodes in flow calculation by the backward or forward sweep method, and reactive power sharing principles and allocation theory are applied to determine initial reactive power value and execute subsequent correction, thus providing the algorithm a better start to speed up the convergence. Finally, a mathematical model of the minimum economic cost is established for the siting and sizing of DGs under the location and capacity uncertainties of each single DG. Its objective function considers investment and operation cost of DGs, grid loss cost, annual purchase electricity cost, and environmental pollution cost, and the constraints include power flow, bus voltage, conductor current, and DG capacity. Through applications in an IEEE33-node distributed system, it is found that the proposed method can achieve desirable economic efficiency and safer voltage level relative to traditional PSO and SA-PSO algorithms, and is a more effective planning method for the siting and sizing of DGs in distributed power grids.

  11. A Process for Site Selection of Reading Recovery Campuses.

    ERIC Educational Resources Information Center

    Jackson, Mary

    1997-01-01

    The Fort Bend Independent School District (a large, growing school district in Sugar Land, Texas) elected to become a Reading Recovery Teacher Training site and faced many decisions regarding effective implementation, including campus (school) selection. They began slowly with only two campuses the first year, added four to five the second year,…

  12. Multi-Modal Active Perception for Autonomously Selecting Landing Sites on Icy Moons

    NASA Technical Reports Server (NTRS)

    Arora, A.; Furlong, P. M.; Wong, U.; Fong, T.; Sukkarieh, S.

    2017-01-01

    Selecting suitable landing sites is fundamental to achieving many mission objectives in planetary robotic lander missions. However, due to sensing limitations, landing sites which are both safe and scientifically valuable often cannot be determined reliably from orbit, particularly, in icy moon missions where orbital sensing data is noisy and incomplete. This paper presents an active perception approach to Entry Descent and Landing (EDL) which enables the lander to autonomously plan informative descent trajectories, acquire high quality sensing data during descent and exploit this additional information to select higher utility landing sites. Our approach consists of two components: probabilistic modeling of landing site features and approximate trajectory planning using a sampling based planner. The proposed framework allows the lander to plan long horizons paths and remain robust to noisy data. Results in simulated environments show large performance improvements over alternative approaches and show promise that our approach has strong potential to improve science return of not only icy moon missions but EDL systems in general.

  13. Does sex-ratio selection influence nest-site choice in a reptile with temperature-dependent sex determination?

    PubMed

    Mitchell, Timothy S; Maciel, Jessica A; Janzen, Fredric J

    2013-12-07

    Evolutionary theory predicts that dioecious species should produce a balanced primary sex ratio maintained by frequency-dependent selection. Organisms with environmental sex determination, however, are vulnerable to maladaptive sex ratios, because environmental conditions vary spatio-temporally. For reptiles with temperature-dependent sex determination, nest-site choice is a behavioural maternal effect that could respond to sex-ratio selection, as mothers could adjust offspring sex ratios by choosing nest sites that will have particular thermal properties. This theoretical prediction has generated decades of empirical research, yet convincing evidence that sex-ratio selection is influencing nesting behaviours remains absent. Here, we provide the first experimental evidence from nature that sex-ratio selection, rather than only viability selection, is probably an important component of nest-site choice in a reptile with temperature-dependent sex determination. We compare painted turtle (Chrysemys picta) neonates from maternally selected nest sites with those from randomly selected nest sites, observing no substantive difference in hatching success or survival, but finding a profound difference in offspring sex ratio in the direction expected based on historical records. Additionally, we leverage long-term data to reconstruct our sex ratio results had the experiment been repeated in multiple years. As predicted by theory, our results suggest that sex-ratio selection has shaped nesting behaviour in ways likely to enhance maternal fitness.

  14. Does sex-ratio selection influence nest-site choice in a reptile with temperature-dependent sex determination?

    PubMed Central

    Mitchell, Timothy S.; Maciel, Jessica A.; Janzen, Fredric J.

    2013-01-01

    Evolutionary theory predicts that dioecious species should produce a balanced primary sex ratio maintained by frequency-dependent selection. Organisms with environmental sex determination, however, are vulnerable to maladaptive sex ratios, because environmental conditions vary spatio-temporally. For reptiles with temperature-dependent sex determination, nest-site choice is a behavioural maternal effect that could respond to sex-ratio selection, as mothers could adjust offspring sex ratios by choosing nest sites that will have particular thermal properties. This theoretical prediction has generated decades of empirical research, yet convincing evidence that sex-ratio selection is influencing nesting behaviours remains absent. Here, we provide the first experimental evidence from nature that sex-ratio selection, rather than only viability selection, is probably an important component of nest-site choice in a reptile with temperature-dependent sex determination. We compare painted turtle (Chrysemys picta) neonates from maternally selected nest sites with those from randomly selected nest sites, observing no substantive difference in hatching success or survival, but finding a profound difference in offspring sex ratio in the direction expected based on historical records. Additionally, we leverage long-term data to reconstruct our sex ratio results had the experiment been repeated in multiple years. As predicted by theory, our results suggest that sex-ratio selection has shaped nesting behaviour in ways likely to enhance maternal fitness. PMID:24266033

  15. 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.

  16. Enhanced Fuzzy-OWA model for municipal solid waste landfill site selection

    NASA Astrophysics Data System (ADS)

    Ahmad, Siti Zubaidah; Ahamad, Mohd Sanusi S.; Yusoff, Mohd Suffian; Abujayyab, Sohaib K. M.

    2017-10-01

    In Malaysia, the municipal solid waste landfill site is an essential facility that needs to be evaluated as its demand is infrequently getting higher. The increment of waste generation forces the government to cater the appropriate site for waste disposal. However, the selection process for new landfill sites is a difficult task with regard to land scarcity and time consumption. In addition, the complication will proliferate when there are various criteria to be considered. Therefore, this paper intends to show the significance of the fuzzy logic-ordered weighted average (Fuzzy-OWA) model for the landfill site suitability analysis. The model was developed to generalize the multi-criteria combination that was extended to the GIS applications as part of the decision support module. OWA has the capability to implement different combination operators through the selection of appropriate order weight that is possible in changing the form of aggregation such as minimum, intermediate and maximum types of combination. OWA give six forms of aggregation results that have their specific significance that indirectly evaluates the environmental, physical and socio-economic (EPSE) criteria respectively. Nevertheless, one of the aggregated results has shown similarity with the weighted linear combination (WLC) method.

  17. Near Surface Swimming of Salmonella Typhimurium Explains Target-Site Selection and Cooperative Invasion

    PubMed Central

    Kreibich, Saskia; Vonaesch, Pascale; Andritschke, Daniel; Rout, Samuel; Weidner, Kerstin; Sormaz, Milos; Songhet, Pascal; Horvath, Peter; Chabria, Mamta; Vogel, Viola; Spori, Doris M.; Jenny, Patrick; Hardt, Wolf-Dietrich

    2012-01-01

    Targeting of permissive entry sites is crucial for bacterial infection. The targeting mechanisms are incompletely understood. We have analyzed target-site selection by S. Typhimurium. This enteropathogenic bacterium employs adhesins (e.g. fim) and the type III secretion system 1 (TTSS-1) for host cell binding, the triggering of ruffles and invasion. Typically, S. Typhimurium invasion is focused on a subset of cells and multiple bacteria invade via the same ruffle. It has remained unclear how this is achieved. We have studied target-site selection in tissue culture by time lapse microscopy, movement pattern analysis and modeling. Flagellar motility (but not chemotaxis) was required for reaching the host cell surface in vitro. Subsequently, physical forces trapped the pathogen for ∼1.5–3 s in “near surface swimming”. This increased the local pathogen density and facilitated “scanning” of the host surface topology. We observed transient TTSS-1 and fim-independent “stopping” and irreversible TTSS-1-mediated docking, in particular at sites of prominent topology, i.e. the base of rounded-up cells and membrane ruffles. Our data indicate that target site selection and the cooperative infection of membrane ruffles are attributable to near surface swimming. This mechanism might be of general importance for understanding infection by flagellated bacteria. PMID:22911370

  18. 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.

  19. Epibenthic assessment of a renewable tidal energy site.

    PubMed

    Sheehan, Emma V; Gall, Sarah C; Cousens, Sophie L; Attrill, Martin J

    2013-01-01

    Concern over global climate change as a result of fossil fuel use has resulted in energy production from renewable sources. Marine renewable energy devices provide clean electricity but can also cause physical disturbance to the local environment. There is a considerable paucity of ecological data at potential marine renewable energy sites that is needed to assess potential future impacts and allow optimal siting of devices. Here, we provide a baseline benthic survey for the Big Russel in Guernsey, UK, a potential site for tidal energy development. To assess the suitability of proposed sites for marine renewable energy in the Big Russel and to identify potential control sites, we compared species assemblages and habitat types. This baseline survey can be used to select control habitats to compare and monitor the benthic communities after installation of the device and contribute towards the optimal siting of any future installation.

  20. Site selection model for new metro stations based on land use

    NASA Astrophysics Data System (ADS)

    Zhang, Nan; Chen, Xuewu

    2015-12-01

    Since the construction of metro system generally lags behind the development of urban land use, sites of metro stations should adapt to their surrounding situations, which was rarely discussed by previous research on station layout. This paper proposes a new site selection model to find the best location for a metro station, establishing the indicator system based on land use and combining AHP with entropy weight method to obtain the schemes' ranking. The feasibility and efficiency of this model has been validated by evaluating Nanjing Shengtai Road station and other potential sites.

  1. Selection of remedial alternatives for mine sites: a multicriteria decision analysis approach.

    PubMed

    Betrie, Getnet D; Sadiq, Rehan; Morin, Kevin A; Tesfamariam, Solomon

    2013-04-15

    The selection of remedial alternatives for mine sites is a complex task because it involves multiple criteria and often with conflicting objectives. However, an existing framework used to select remedial alternatives lacks multicriteria decision analysis (MCDA) aids and does not consider uncertainty in the selection of alternatives. The objective of this paper is to improve the existing framework by introducing deterministic and probabilistic MCDA methods. The Preference Ranking Organization Method for Enrichment Evaluation (PROMETHEE) methods have been implemented in this study. The MCDA analysis involves processing inputs to the PROMETHEE methods that are identifying the alternatives, defining the criteria, defining the criteria weights using analytical hierarchical process (AHP), defining the probability distribution of criteria weights, and conducting Monte Carlo Simulation (MCS); running the PROMETHEE methods using these inputs; and conducting a sensitivity analysis. A case study was presented to demonstrate the improved framework at a mine site. The results showed that the improved framework provides a reliable way of selecting remedial alternatives as well as quantifying the impact of different criteria on selecting alternatives. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. 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…

  3. 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.

  4. Management decision of optimal recharge water in groundwater artificial recharge conditions- A case study in an artificial recharge test site

    NASA Astrophysics Data System (ADS)

    He, H. Y.; Shi, X. F.; Zhu, W.; Wang, C. Q.; Ma, H. W.; Zhang, W. J.

    2017-11-01

    The city conducted groundwater artificial recharge test which was taken a typical site as an example, and the purpose is to prevent and control land subsidence, increase the amount of groundwater resources. To protect groundwater environmental quality and safety, the city chose tap water as recharge water, however, the high cost makes it not conducive to the optimal allocation of water resources and not suitable to popularize widely. To solve this, the city selects two major surface water of River A and B as the proposed recharge water, to explore its feasibility. According to a comprehensive analysis of the cost of recharge, the distance of the water transport, the quality of recharge water and others. Entropy weight Fuzzy Comprehensive Evaluation Method is used to prefer tap water and water of River A and B. Evaluation results show that water of River B is the optimal recharge water, if used; recharge cost will be from 0.4724/m3 to 0.3696/m3. Using Entropy weight Fuzzy Comprehensive Evaluation Method to confirm water of River B as optimal water is scientific and reasonable. The optimal water management decisions can provide technical support for the city to carry out overall groundwater artificial recharge engineering in deep aquifer.

  5. Weak Negative and Positive Selection and the Drift Load at Splice Sites

    PubMed Central

    Denisov, Stepan V.; Bazykin, Georgii A.; Sutormin, Roman; Favorov, Alexander V.; Mironov, Andrey A.; Gelfand, Mikhail S.; Kondrashov, Alexey S.

    2014-01-01

    Splice sites (SSs) are short sequences that are crucial for proper mRNA splicing in eukaryotic cells, and therefore can be expected to be shaped by strong selection. Nevertheless, in mammals and in other intron-rich organisms, many of the SSs often involve nonconsensus (Nc), rather than consensus (Cn), nucleotides, and beyond the two critical nucleotides, the SSs are not perfectly conserved between species. Here, we compare the SS sequences between primates, and between Drosophila fruit flies, to reveal the pattern of selection acting at SSs. Cn-to-Nc substitutions are less frequent, and Nc-to-Cn substitutions are more frequent, than neutrally expected, indicating, respectively, negative and positive selection. This selection is relatively weak (1 < |4Nes| < 4), and has a similar efficiency in primates and in Drosophila. Within some nucleotide positions, the positive selection in favor of Nc-to-Cn substitutions is weaker than the negative selection maintaining already established Cn nucleotides; this difference is due to site-specific negative selection favoring current Nc nucleotides. In general, however, the strength of negative selection protecting the Cn alleles is similar in magnitude to the strength of positive selection favoring replacement of Nc alleles, as expected under the simple nearly neutral turnover. In summary, although a fraction of the Nc nucleotides within SSs is maintained by selection, the abundance of deleterious nucleotides in this class suggests a substantial genome-wide drift load. PMID:24966225

  6. The importance of environmental quality and catch potential to fishing site selection by freshwater anglers in Mississippi

    USGS Publications Warehouse

    Schramm, H.L.; Gerard, P.D.; Gill, D.A.

    2003-01-01

    We measured the importance of 24 fishing site attributes to Mississippi freshwater anglers. Factor analysis identified four multiattribute factors as important in the selection of fishing location: CLEAN ENVIRONMENT CATCH, COST AND HARVEST and AMENITIES AND SAFETY. In general, the importance of site selection factors differed little among anglers grouped by preferred type of fish, preferred fishing location (lakes and reservoirs, rivers and streams, ponds, or reservoir tailwaters), usual manner of fishing (engine-powered boat, nonpowered boat, or shore), or change in fishing frequency. COST AND HARVEST was more important to anglers with high harvest orientations. We found low correlations between site selection factor importance scores and angler age, fishing frequency, fishing expenditures, or fishing motivation factors. We suggest that the general lack of differences in site selection factors among angler groups indicates that management strategies to improve fishing site attributes should benefit all angler groups. Clean fishing environments and awareness of the availability of desired sport fishes were "very" or "extremely" important to fishing site selection by more than 70% of Mississippi freshwater anglers and should be priority management objectives.

  7. 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.

  8. Directed evolution of glutathione transferases towards a selective glutathione-binding site and improved oxidative stability.

    PubMed

    Axarli, Irine; Muleta, Abdi W; Chronopoulou, Evangelia G; Papageorgiou, Anastassios C; Labrou, Nikolaos E

    2017-01-01

    Glutathione transferases (GSTs) are a family of detoxification enzymes that catalyze the conjugation of glutathione (GSH) to electrophilic compounds. A library of alpha class GSTs was constructed by DNA shuffling using the DNA encoding the human glutathione transferase A1-1 (hGSTA1-1) and the rat glutathione transferase A1-1 (rGSTA1-1). Activity screening of the library allowed the selection of a chimeric enzyme variant (GSTD4) that displayed high affinity towards GSH and GSH-Sepharose affinity adsorbent, higher k cat /K m and improved thermal stability, compared to the parent enzymes. The crystal structures of the GSTD4 enzyme in free form and in complex with GSH were determined to 1.6Šand 2.3Šresolution, respectively. Analysis of the GSTD4 structure showed subtle conformational changes in the GSH-binding site and in electron-sharing network that may contribute to the increased GSH affinity. The shuffled variant GSTD4 was further optimized for improved oxidative stability employing site-saturation mutagenesis. The Cys112Ser mutation confers optimal oxidative stability and kinetic properties in the GSTD4 enzyme. DNA shuffling allowed the creation of a chimeric enzyme variant with improved properties, compared to the parent enzymes. X-ray crystallography shed light on how recombination of a specific segment from homologous GSTA1-1 together with point mutations gives rise to a new functionally competent enzyme with improved binding, catalytic properties and stability. Such an engineered GST would be useful in biotechnology as affinity tool in affinity chromatography as well as a biocatalytic matrix for the construction of biochips or enzyme biosensors. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Site-selective post-translational modification of proteins using an unnatural amino acid, 3-azidotyrosine.

    PubMed

    Ohno, Satoshi; Matsui, Megumi; Yokogawa, Takashi; Nakamura, Masashi; Hosoya, Takamitsu; Hiramatsu, Toshiyuki; Suzuki, Masaaki; Hayashi, Nobuhiro; Nishikawa, Kazuya

    2007-03-01

    An efficient method for site-selective modification of proteins using an unnatural amino acid, 3-azidotyrosine has been developed. This method utilizes the yeast amber suppressor tRNA(Tyr)/mutated tyrosyl-tRNA synthetase pair as a carrier of 3-azidotyrosine in an Escherichia coli cell-free translation system, and triarylphosphine derivatives for specific modification of the azido group. Using rat calmodulin (CaM) as a model protein, we prepared several unnatural CaM molecules, each carrying an azidotyrosine at predetermined positions 72, 78, 80 or 100, respectively. Post-translational modification of these proteins with a conjugate compound of triarylphosphine and biotin produced site-selectively biotinylated CaM molecules. Reaction efficiency was similar among these proteins irrespective of the position of introduction, and site-specificity of biotinylation was confirmed using mass spectrometry. In addition, CBP-binding activity of the biotinylated CaMs was confirmed to be similar to that of wild-type CaM. This method is intrinsically versatile in that it should be easily applicable to introducing any other desirable compounds (e.g., probes and cross-linkers) into selected sites of proteins as far as appropriate derivative compounds of triarylphosphine could be chemically synthesized. Elucidation of molecular mechanisms of protein functions and protein-to-protein networks will be greatly facilitated by making use of these site-selectively modified proteins.

  10. Communication: Site-selective bond excision of adenine upon electron transfer

    NASA Astrophysics Data System (ADS)

    Cunha, T.; Mendes, M.; Ferreira da Silva, F.; Eden, S.; García, G.; Limão-Vieira, P.

    2018-01-01

    This work demonstrates that selective excision of hydrogen atoms at a particular site of the DNA base adenine can be achieved in collisions with electronegative atoms by controlling the impact energy. The result is based on analysing the time-of-flight mass spectra yields of potassium collisions with a series of labeled adenine derivatives. The production of dehydrogenated parent anions is consistent with neutral H loss either from selective breaking of C-H or N-H bonds. These unprecedented results open up a new methodology in charge transfer collisions that can initiate selective reactivity as a key process in chemical reactions that are dominant in different areas of science and technology.

  11. 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…

  12. 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

  13. Artificial Intelligence Based Selection of Optimal Cutting Tool and Process Parameters for Effective Turning and Milling Operations

    NASA Astrophysics Data System (ADS)

    Saranya, Kunaparaju; John Rozario Jegaraj, J.; Ramesh Kumar, Katta; Venkateshwara Rao, Ghanta

    2016-06-01

    With the increased trend in automation of modern manufacturing industry, the human intervention in routine, repetitive and data specific activities of manufacturing is greatly reduced. In this paper, an attempt has been made to reduce the human intervention in selection of optimal cutting tool and process parameters for metal cutting applications, using Artificial Intelligence techniques. Generally, the selection of appropriate cutting tool and parameters in metal cutting is carried out by experienced technician/cutting tool expert based on his knowledge base or extensive search from huge cutting tool database. The present proposed approach replaces the existing practice of physical search for tools from the databooks/tool catalogues with intelligent knowledge-based selection system. This system employs artificial intelligence based techniques such as artificial neural networks, fuzzy logic and genetic algorithm for decision making and optimization. This intelligence based optimal tool selection strategy is developed using Mathworks Matlab Version 7.11.0 and implemented. The cutting tool database was obtained from the tool catalogues of different tool manufacturers. This paper discusses in detail, the methodology and strategies employed for selection of appropriate cutting tool and optimization of process parameters based on multi-objective optimization criteria considering material removal rate, tool life and tool cost.

  14. 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

  15. A Multi-Site Study on Medical School Selection, Performance, Motivation and Engagement

    ERIC Educational Resources Information Center

    Wouters, A.; Croiset, G.; Schripsema, N. R.; Cohen-Schotanus, J.; Spaai, G. W.; Hulsman, R. L.; Kusurkar, R. A.

    2017-01-01

    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…

  16. Winter roost-site selection by seminole bats in the lower coastal plain of South Carolina

    Treesearch

    Cris D. Hein; Steven B. Castleberry; Karl V. Miller

    2005-01-01

    The winter roost-site selection of most North American foliage-roosting bats is relatively unknown. We examined winter roost-site selection of Seminole bats (Lasiurus seminolus) in the Lower Coastal Plain of South Carolina during January 2004. Seminole bats used a variety of day-roost structures including the canopy of overstory hardwood trees,...

  17. Issues and recent advances in optimal experimental design for site investigation (Invited)

    NASA Astrophysics Data System (ADS)

    Nowak, W.

    2013-12-01

    This presentation provides an overview over issues and recent advances in model-based experimental design for site exploration. The addressed issues and advances are (1) how to provide an adequate envelope to prior uncertainty, (2) how to define the information needs in a task-oriented manner, (3) how to measure the expected impact of a data set that it not yet available but only planned to be collected, and (4) how to perform best the optimization of the data collection plan. Among other shortcomings of the state-of-the-art, it is identified that there is a lack of demonstrator studies where exploration schemes based on expert judgment are compared to exploration schemes obtained by optimal experimental design. Such studies will be necessary do address the often voiced concern that experimental design is an academic exercise with little improvement potential over the well- trained gut feeling of field experts. When addressing this concern, a specific focus has to be given to uncertainty in model structure, parameterizations and parameter values, and to related surprises that data often bring about in field studies, but never in synthetic-data based studies. The background of this concern is that, initially, conceptual uncertainty may be so large that surprises are the rule rather than the exception. In such situations, field experts have a large body of experience in handling the surprises, and expert judgment may be good enough compared to meticulous optimization based on a model that is about to be falsified by the incoming data. In order to meet surprises accordingly and adapt to them, there needs to be a sufficient representation of conceptual uncertainty within the models used. Also, it is useless to optimize an entire design under this initial range of uncertainty. Thus, the goal setting of the optimization should include the objective to reduce conceptual uncertainty. A possible way out is to upgrade experimental design theory towards real-time interaction

  18. 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...

  19. Nursing performance under high workload: a diary study on the moderating role of selection, optimization and compensation strategies.

    PubMed

    Baethge, Anja; Müller, Andreas; Rigotti, Thomas

    2016-03-01

    The aim of this study was to investigate whether selective optimization with compensation constitutes an individualized action strategy for nurses wanting to maintain job performance under high workload. High workload is a major threat to healthcare quality and performance. Selective optimization with compensation is considered to enhance the efficient use of intra-individual resources and, therefore, is expected to act as a buffer against the negative effects of high workload. The study applied a diary design. Over five consecutive workday shifts, self-report data on workload was collected at three randomized occasions during each shift. Self-reported job performance was assessed in the evening. Self-reported selective optimization with compensation was assessed prior to the diary reporting. Data were collected in 2010. Overall, 136 nurses from 10 German hospitals participated. Selective optimization with compensation was assessed with a nine-item scale that was specifically developed for nursing. The NASA-TLX scale indicating the pace of task accomplishment was used to measure workload. Job performance was assessed with one item each concerning performance quality and forgetting of intentions. There was a weaker negative association between workload and both indicators of job performance in nurses with a high level of selective optimization with compensation, compared with nurses with a low level. Considering the separate strategies, selection and compensation turned out to be effective. The use of selective optimization with compensation is conducive to nurses' job performance under high workload levels. This finding is in line with calls to empower nurses' individual decision-making. © 2015 John Wiley & Sons Ltd.

  20. 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

  1. Efficient and surface site-selective ion desorption by positron annihilation.

    PubMed

    Tachibana, Takayuki; Yamashita, Takashi; Nagira, Masaru; Yabuki, Hisakuni; Nagashima, Yasuyuki

    2018-05-08

    We compared positron- and electron-stimulated desorption (e + SD and ESD) of positive ions from a TiO 2 (110) surface. Although desorption of O + ions was observed in both experiments, the desorption efficiency caused by positron bombardment was larger by one order of magnitude than that caused by electron bombardment at an incident energy of 500 eV. e + SD of O + ions remained highly efficient with incident positron energies between 10 eV and 600 eV. The results indicate that e + SD of O + ions is predominantly caused by pair annihilation of surface-trapped positrons with inner-shell electrons. We also tested e + SD from water chemisorbed on the TiO 2 surface and found that the desorption of specific ions was enhanced by positron annihilation, above the ion yield with electron bombardment. This finding corroborates our conclusion that annihilation-site selectivity of positrons results in site-selective ion desorption from a bombarded surface.

  2. Pre‐moult patterns of habitat use and moult site selection by Brent Geese Branta bernicla nigricans: Individuals prospect for moult sites

    USGS Publications Warehouse

    Lewis, Tyler; Flint, Paul L.; Schmutz, Joel A.; Derksen, Dirk V.

    2010-01-01

    In environments where habitat quality varies, the mechanism by which individuals assess and select habitats has significant consequences on their spatial distribution and ability to respond to environmental change. Each year, thousands of Black Brent Geese Branta bernicla nigricans migrate to the Teshekpuk Lake Special Area (TLSA), Alaska, to undergo a flightless wing‐moult. Over the last three decades, moulting Brent Geese have changed their distribution within the TLSA, redistributing from inland, freshwater wetlands towards coastal, brackish wetlands. To understand better the mechanism by which Brent Geese select a moult site, as well as reasons behind the long‐term shift of moulting distributions, we examined movements and habitat use of birds marked with GPS‐transmitters during the pre‐moult period. Brent Geese did not generally migrate directly to their moulting site during the pre‐moult period, defined as the time from arrival at the moulting grounds to the onset of flightlessness. Rather, individuals used an average of 3.7 ± 0.6 (se) wetland complexes and travelled a minimum of 95.14 ± 15.84 km during the pre‐moult period. Moreover, 69% of Brent Geese visited their final moult site only to leave and visit other sites before returning for the flightless moult. Brent Geese spent significant time in both inland freshwater and coastal estuarine habitats during the pre‐moult, irrespective of the habitat in which they ultimately moulted. Whereas previous research suggested that Brent Geese choose moult sites based largely upon the experience of previous years, our observations suggest a mechanism of moult site selection whereby Brent Geese ‘prospect’ for moult sites, visiting multiple potential moult sites across varied habitat types, presumably gathering information from each site and correspondingly using this information to choose an appropriate moult site. By allowing individuals to adjust their distributions in response to habitat

  3. 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.

  4. Despotism and risk of infanticide influence grizzly bear den-site selection.

    PubMed

    Libal, Nathan S; Belant, Jerrold L; Leopold, Bruce D; Wang, Guiming; Owen, Patricia A

    2011-01-01

    Given documented social dominance and intraspecific predation in bear populations, the ideal despotic distribution model and sex hypothesis of sexual segregation predict adult female grizzly bears (Ursus arctos) will avoid areas occupied by adult males to reduce risk of infanticide. Under ideal despotic distribution, juveniles should similarly avoid adult males to reduce predation risk. Den-site selection and use is an important component of grizzly bear ecology and may be influenced by multiple factors, including risk from conspecifics. To test the role of predation risk and the sex hypothesis of sexual segregation, we compared adult female (n = 142), adult male (n = 36), and juvenile (n = 35) den locations in Denali National Park and Preserve, Alaska, USA. We measured elevation, aspect, slope, and dominant land cover for each den site, and used maximum entropy modeling to determine which variables best predicted den sites. We identified the global model as the best-fitting model for adult female (area under curve (AUC) = 0.926) and elevation as the best predictive variable for adult male (AUC = 0.880) den sites. The model containing land cover and elevation best-predicted juvenile (AUC = 0.841) den sites. Adult females spatially segregated from adult males, with dens characterized by higher elevations (mean= 1,412 m, SE = 52) and steeper slopes (mean = 21.9°, SE = 1.1) than adult male (elevation: mean = 1,209 m, SE = 76; slope: mean = 15.6°, SE = 1.9) den sites. Juveniles used a broad range of landscape attributes but did not avoid adult male denning areas. Observed spatial segregation by adult females supports the sex hypothesis of sexual segregation and we suggest is a mechanism to reduce risk of infanticide. Den site selection of adult males is likely related to distribution of food resources during spring.

  5. Parameter sensitivity analysis and optimization for a satellite-based evapotranspiration model across multiple sites using Moderate Resolution Imaging Spectroradiometer and flux data

    NASA Astrophysics Data System (ADS)

    Zhang, Kun; Ma, Jinzhu; Zhu, Gaofeng; Ma, Ting; Han, Tuo; Feng, Li Li

    2017-01-01

    Global and regional estimates of daily evapotranspiration are essential to our understanding of the hydrologic cycle and climate change. In this study, we selected the radiation-based Priestly-Taylor Jet Propulsion Laboratory (PT-JPL) model and assessed it at a daily time scale by using 44 flux towers. These towers distributed in a wide range of ecological systems: croplands, deciduous broadleaf forest, evergreen broadleaf forest, evergreen needleleaf forest, grasslands, mixed forests, savannas, and shrublands. A regional land surface evapotranspiration model with a relatively simple structure, the PT-JPL model largely uses ecophysiologically-based formulation and parameters to relate potential evapotranspiration to actual evapotranspiration. The results using the original model indicate that the model always overestimates evapotranspiration in arid regions. This likely results from the misrepresentation of water limitation and energy partition in the model. By analyzing physiological processes and determining the sensitive parameters, we identified a series of parameter sets that can increase model performance. The model with optimized parameters showed better performance (R2 = 0.2-0.87; Nash-Sutcliffe efficiency (NSE) = 0.1-0.87) at each site than the original model (R2 = 0.19-0.87; NSE = -12.14-0.85). The results of the optimization indicated that the parameter β (water control of soil evaporation) was much lower in arid regions than in relatively humid regions. Furthermore, the optimized value of parameter m1 (plant control of canopy transpiration) was mostly between 1 to 1.3, slightly lower than the original value. Also, the optimized parameter Topt correlated well to the actual environmental temperature at each site. We suggest that using optimized parameters with the PT-JPL model could provide an efficient way to improve the model performance.

  6. Estimated and measured bridge scour at selected sites in North Dakota, 1990-97

    USGS Publications Warehouse

    Williams-Sether, Tara

    1999-01-01

    A Level 2 bridge scour method was used to estimate scour depths at 36 selected bridge sites located on the primary road system throughout North Dakota. Of the 36 bridge sites analyzed, the North Dakota Department of Transportation rated 15 as scour critical. Flood and scour data were collected at 19 of the 36 selected bridge sites during 1990-97. Data collected were sufficient to estimate pier scour but not contraction or abutment scour. Estimated pier scour depths ranged from -10.6 to -1.2 feet, and measured bed-elevation changes at piers ranged from -2.31 to +2.37 feet. Comparisons between the estimated pier scour depths and the measured bed-elevation changes indicate that the pier scour equations overestimate scour at bridges in North Dakota.A Level 1.5 bridge scour method also was used to estimate scour depths at 495 bridge sites located on the secondary road system throughout North Dakota. The North Dakota Department of Transportation determined that 26 of the 495 bridge sites analyzed were potentially scour critical.

  7. 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

  8. Multidimensional Programming Methods for Energy Facility Siting: Alternative Approaches

    NASA Technical Reports Server (NTRS)

    Solomon, B. D.; Haynes, K. E.

    1982-01-01

    The use of multidimensional optimization methods in solving power plant siting problems, which are characterized by several conflicting, noncommensurable objectives is addressed. After a discussion of data requirements and exclusionary site screening methods for bounding the decision space, classes of multiobjective and goal programming models are discussed in the context of finite site selection. Advantages and limitations of these approaches are highlighted and the linkage of multidimensional methods with the subjective, behavioral components of the power plant siting process is emphasized.

  9. The Application of Optimal Defaults to Improve Elementary School Lunch Selections: Proof of Concept

    ERIC Educational Resources Information Center

    Loeb, Katharine L.; Radnitz, Cynthia; Keller, Kathleen L.; Schwartz, Marlene B.; Zucker, Nancy; Marcus, Sue; Pierson, Richard N.; Shannon, Michael; DeLaurentis, Danielle

    2018-01-01

    Background: In this study, we applied behavioral economics to optimize elementary school lunch choices via parent-driven decisions. Specifically, this experiment tested an optimal defaults paradigm, examining whether strategically manipulating the health value of a default menu could be co-opted to improve school-based lunch selections. Methods:…

  10. 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

  11. Tricyclic Covalent Inhibitors Selectively Target Jak3 through an Active Site Thiol

    DOE PAGES

    Goedken, Eric R.; Argiriadi, Maria A.; Banach, David L.; ...

    2014-12-31

    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. In this paper, 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). Wemore » 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 (IC 50 < 100 nM) inhibit Jak3 activity in cell-based assays. Finally, 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.« less

  12. Tricyclic Covalent Inhibitors Selectively Target Jak3 through an Active Site Thiol

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

    Goedken, Eric R.; Argiriadi, Maria A.; Banach, David L.

    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. In this paper, 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). Wemore » 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 (IC 50 < 100 nM) inhibit Jak3 activity in cell-based assays. Finally, 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.« less

  13. Spatial optimization of watershed management practices for nitrogen load reduction using a modeling-optimization framework.

    PubMed

    Yang, Guoxiang; Best, Elly P H

    2015-09-15

    Best management practices (BMPs) can be used effectively to reduce nutrient loads transported from non-point sources to receiving water bodies. However, methodologies of BMP selection and placement in a cost-effective way are needed to assist watershed management planners and stakeholders. We developed a novel modeling-optimization framework that can be used to find cost-effective solutions of BMP placement to attain nutrient load reduction targets. This was accomplished by integrating a GIS-based BMP siting method, a WQM-TMDL-N modeling approach to estimate total nitrogen (TN) loading, and a multi-objective optimization algorithm. Wetland restoration and buffer strip implementation were the two BMP categories used to explore the performance of this framework, both differing greatly in complexity of spatial analysis for site identification. Minimizing TN load and BMP cost were the two objective functions for the optimization process. The performance of this framework was demonstrated in the Tippecanoe River watershed, Indiana, USA. Optimized scenario-based load reduction indicated that the wetland subset selected by the minimum scenario had the greatest N removal efficiency. Buffer strips were more effective for load removal than wetlands. The optimized solutions provided a range of trade-offs between the two objective functions for both BMPs. This framework can be expanded conveniently to a regional scale because the NHDPlus catchment serves as its spatial computational unit. The present study demonstrated the potential of this framework to find cost-effective solutions to meet a water quality target, such as a 20% TN load reduction, under different conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Reserve selection with land market feedbacks.

    PubMed

    Butsic, Van; Lewis, David J; Radeloff, Volker C

    2013-01-15

    How to best site reserves is a leading question for conservation biologists. Recently, reserve selection has emphasized efficient conservation: maximizing conservation goals given the reality of limited conservation budgets, and this work indicates that land market can potentially undermine the conservation benefits of reserves by increasing property values and development probabilities near reserves. Here we propose a reserve selection methodology which optimizes conservation given both a budget constraint and land market feedbacks by using a combination of econometric models along with stochastic dynamic programming. We show that amenity based feedbacks can be accounted for in optimal reserve selection by choosing property price and land development models which exogenously estimate the effects of reserve establishment. In our empirical example, we use previously estimated models of land development and property prices to select parcels to maximize coarse woody debris along 16 lakes in Vilas County, WI, USA. Using each lake as an independent experiment, we find that including land market feedbacks in the reserve selection algorithm has only small effects on conservation efficacy. Likewise, we find that in our setting heuristic (minloss and maxgain) algorithms perform nearly as well as the optimal selection strategy. We emphasize that land market feedbacks can be included in optimal reserve selection; the extent to which this improves reserve placement will likely vary across landscapes. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Location Distribution Optimization of Photographing Sites for Indoor Panorama Modeling

    NASA Astrophysics Data System (ADS)

    Zhang, S.; Wu, J.; Zhang, Y.; Zhang, X.; Xin, Z.; Liu, J.

    2017-09-01

    Generally, panoramas image modeling is costly and time-consuming because of photographing continuously to capture enough photos along the routes, especially in complicated indoor environment. Thus, difficulty follows for a wider applications of panoramic image modeling for business. It is indispensable to make a feasible arrangement of panorama sites locations because the locations influence the clarity, coverage and the amount of panoramic images under the condition of certain device. This paper is aim to propose a standard procedure to generate the specific location and total amount of panorama sites in indoor panoramas modeling. Firstly, establish the functional relationship between one panorama site and its objectives. Then, apply the relationship to panorama sites network. We propose the Distance Clarity function (FC and Fe) manifesting the mathematical relationship between panoramas and objectives distance or obstacle distance. The Distance Buffer function (FB) is modified from traditional buffer method to generate the coverage of panorama site. Secondly, transverse every point in possible area to locate possible panorama site, calculate the clarity and coverage synthetically. Finally select as little points as possible to satiate clarity requirement preferentially and then the coverage requirement. In the experiments, detailed parameters of camera lens are given. Still, more experiments parameters need trying out given that relationship between clarity and distance is device dependent. In short, through the function FC, Fe and FB, locations of panorama sites can be generated automatically and accurately.

  16. Parallel algorithms for islanded microgrid with photovoltaic and energy storage systems planning optimization problem: Material selection and quantity demand optimization

    NASA Astrophysics Data System (ADS)

    Cao, Yang; Liu, Chun; Huang, Yuehui; Wang, Tieqiang; Sun, Chenjun; Yuan, Yue; Zhang, Xinsong; Wu, Shuyun

    2017-02-01

    With the development of roof photovoltaic power (PV) generation technology and the increasingly urgent need to improve supply reliability levels in remote areas, islanded microgrid with photovoltaic and energy storage systems (IMPE) is developing rapidly. The high costs of photovoltaic panel material and energy storage battery material have become the primary factors that hinder the development of IMPE. The advantages and disadvantages of different types of photovoltaic panel materials and energy storage battery materials are analyzed in this paper, and guidance is provided on material selection for IMPE planners. The time sequential simulation method is applied to optimize material demands of the IMPE. The model is solved by parallel algorithms that are provided by a commercial solver named CPLEX. Finally, to verify the model, an actual IMPE is selected as a case system. Simulation results on the case system indicate that the optimization model and corresponding algorithm is feasible. Guidance for material selection and quantity demand for IMPEs in remote areas is provided by this method.

  17. 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

  18. 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.

  19. A novel variable selection approach that iteratively optimizes variable space using weighted binary matrix sampling.

    PubMed

    Deng, Bai-chuan; Yun, Yong-huan; Liang, Yi-zeng; Yi, Lun-zhao

    2014-10-07

    In this study, a new optimization algorithm called the Variable Iterative Space Shrinkage Approach (VISSA) that is based on the idea of model population analysis (MPA) is proposed for variable selection. Unlike most of the existing optimization methods for variable selection, VISSA statistically evaluates the performance of variable space in each step of optimization. Weighted binary matrix sampling (WBMS) is proposed to generate sub-models that span the variable subspace. Two rules are highlighted during the optimization procedure. First, the variable space shrinks in each step. Second, the new variable space outperforms the previous one. The second rule, which is rarely satisfied in most of the existing methods, is the core of the VISSA strategy. Compared with some promising variable selection methods such as competitive adaptive reweighted sampling (CARS), Monte Carlo uninformative variable elimination (MCUVE) and iteratively retaining informative variables (IRIV), VISSA showed better prediction ability for the calibration of NIR data. In addition, VISSA is user-friendly; only a few insensitive parameters are needed, and the program terminates automatically without any additional conditions. The Matlab codes for implementing VISSA are freely available on the website: https://sourceforge.net/projects/multivariateanalysis/files/VISSA/.

  20. General equations for optimal selection of diagnostic image acquisition parameters in clinical X-ray imaging.

    PubMed

    Zheng, Xiaoming

    2017-12-01

    The purpose of this work was to examine the effects of relationship functions between diagnostic image quality and radiation dose on the governing equations for image acquisition parameter variations in X-ray imaging. Various equations were derived for the optimal selection of peak kilovoltage (kVp) and exposure parameter (milliAmpere second, mAs) in computed tomography (CT), computed radiography (CR), and direct digital radiography. Logistic, logarithmic, and linear functions were employed to establish the relationship between radiation dose and diagnostic image quality. The radiation dose to the patient, as a function of image acquisition parameters (kVp, mAs) and patient size (d), was used in radiation dose and image quality optimization. Both logistic and logarithmic functions resulted in the same governing equation for optimal selection of image acquisition parameters using a dose efficiency index. For image quality as a linear function of radiation dose, the same governing equation was derived from the linear relationship. The general equations should be used in guiding clinical X-ray imaging through optimal selection of image acquisition parameters. The radiation dose to the patient could be reduced from current levels in medical X-ray imaging.

  1. Tuning a Protein-Labeling Reaction to Achieve Highly Site Selective Lysine Conjugation.

    PubMed

    Pham, Grace H; Ou, Weijia; Bursulaya, Badry; DiDonato, Michael; Herath, Ananda; Jin, Yunho; Hao, Xueshi; Loren, Jon; Spraggon, Glen; Brock, Ansgar; Uno, Tetsuo; Geierstanger, Bernhard H; Cellitti, Susan E

    2018-04-16

    Activated esters are widely used to label proteins at lysine side chains and N termini. These reagents are useful for labeling virtually any protein, but robust reactivity toward primary amines generally precludes site-selective modification. In a unique case, fluorophenyl esters are shown to preferentially label human kappa antibodies at a single lysine (Lys188) within the light-chain constant domain. Neighboring residues His189 and Asp151 contribute to the accelerated rate of labeling at Lys188 relative to the ≈40 other lysine sites. Enriched Lys188 labeling can be enhanced from 50-70 % to >95 % by any of these approaches: lowering reaction temperature, applying flow chemistry, or mutagenesis of specific residues in the surrounding protein environment. Our results demonstrated that activated esters with fluoro-substituted aromatic leaving groups, including a fluoronaphthyl ester, can be generally useful reagents for site-selective lysine labeling of antibodies and other immunoglobulin-type proteins. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Influence of olfactory and visual cover on nest site selection and nest success for grassland-nesting birds.

    PubMed

    Fogarty, Dillon T; Elmore, R Dwayne; Fuhlendorf, Samuel D; Loss, Scott R

    2017-08-01

    Habitat selection by animals is influenced by and mitigates the effects of predation and environmental extremes. For birds, nest site selection is crucial to offspring production because nests are exposed to extreme weather and predation pressure. Predators that forage using olfaction often dominate nest predator communities; therefore, factors that influence olfactory detection (e.g., airflow and weather variables, including turbulence and moisture) should influence nest site selection and survival. However, few studies have assessed the importance of olfactory cover for habitat selection and survival. We assessed whether ground-nesting birds select nest sites based on visual and/or olfactory cover. Additionally, we assessed the importance of visual cover and airflow and weather variables associated with olfactory cover in influencing nest survival. In managed grasslands in Oklahoma, USA, we monitored nests of Northern Bobwhite ( Colinus virginianus ), Eastern Meadowlark ( Sturnella magna ), and Grasshopper Sparrow ( Ammodramus savannarum ) during 2015 and 2016. To assess nest site selection, we compared cover variables between nests and random points. To assess factors influencing nest survival, we used visual cover and olfactory-related measurements (i.e., airflow and weather variables) to model daily nest survival. For nest site selection, nest sites had greater overhead visual cover than random points, but no other significant differences were found. Weather variables hypothesized to influence olfactory detection, specifically precipitation and relative humidity, were the best predictors of and were positively related to daily nest survival. Selection for overhead cover likely contributed to mitigation of thermal extremes and possibly reduced detectability of nests. For daily nest survival, we hypothesize that major nest predators focused on prey other than the monitored species' nests during high moisture conditions, thus increasing nest survival on these

  3. 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

  4. Optimizing the sequence of diameter distributions and selection harvests for uneven-aged stand management

    Treesearch

    Robert G. Haight; J. Douglas Brodie; Darius M. Adams

    1985-01-01

    The determination of an optimal sequence of diameter distributions and selection harvests for uneven-aged stand management is formulated as a discrete-time optimal-control problem with bounded control variables and free-terminal point. An efficient programming technique utilizing gradients provides solutions that are stable and interpretable on the basis of economic...

  5. Spotted owl roost and nest site selection in northwestern California

    Treesearch

    J.A. Blakesley; A.B. Franklin; R.J. Gutierrez

    1992-01-01

    We directly observed roost and nest site selection in a population of northern spotted owls (Strix occidentalis caurina) in northwestern California during 1985-89. Because of potential biases caused by use of radio telemetry in previous studies, we examined habitat use relative to habitat availability at a level not previously reported for spotted...

  6. A method of selecting forest sites for air pollution study

    Treesearch

    Sreedevi K. Bringi; Thomas A. Seliga; Leon S. Dochinger

    1981-01-01

    Presents a method of selecting suitable forested areas for meaningful assessments of air pollution effects. The approach is based on the premise that environmental influences can significantly affect the forest-air pollution relationship, and that it is, therefore, desirable to equalize such influences at different sites. From existing data on environmental factors and...

  7. On-Site Additive Manufacturing by Selective Laser Melting of Composite Objects

    NASA Astrophysics Data System (ADS)

    Fateri, M.; Khosravi, M.

    2012-06-01

    This paper proposes a method for cost reduction of future space missions by manufacturing parts on foreign planets. The suitability of Selective Laser Melting process for on-site production of metallic, ceramic and glass products on mars is examined.

  8. GIS-based approach for optimal siting and sizing of renewables considering techno-environmental constraints and the stochastic nature of meteorological inputs

    NASA Astrophysics Data System (ADS)

    Daskalou, Olympia; Karanastasi, Maria; Markonis, Yannis; Dimitriadis, Panayiotis; Koukouvinos, Antonis; Efstratiadis, Andreas; Koutsoyiannis, Demetris

    2016-04-01

    Following the legislative EU targets and taking advantage of its high renewable energy potential, Greece can obtain significant benefits from developing its water, solar and wind energy resources. In this context we present a GIS-based methodology for the optimal sizing and siting of solar and wind energy systems at the regional scale, which is tested in the Prefecture of Thessaly. First, we assess the wind and solar potential, taking into account the stochastic nature of the associated meteorological processes (i.e. wind speed and solar radiation, respectively), which is essential component for both planning (i.e., type selection and sizing of photovoltaic panels and wind turbines) and management purposes (i.e., real-time operation of the system). For the optimal siting, we assess the efficiency and economic performance of the energy system, also accounting for a number of constraints, associated with topographic limitations (e.g., terrain slope, proximity to road and electricity grid network, etc.), the environmental legislation and other land use constraints. Based on this analysis, we investigate favorable alternatives using technical, environmental as well as financial criteria. The final outcome is GIS maps that depict the available energy potential and the optimal layout for photovoltaic panels and wind turbines over the study area. We also consider a hypothetical scenario of future development of the study area, in which we assume the combined operation of the above renewables with major hydroelectric dams and pumped-storage facilities, thus providing a unique hybrid renewable system, extended at the regional scale.

  9. San Andreas drilling sites selected

    NASA Astrophysics Data System (ADS)

    Ellsworth, Bill; Zoback, Mark

    A new initiative for drilling and coring directly into the San Andreas fault at depths up to 10 km is being proposed by an international team of scientists led by Mark Zoback, Stanford University; Steve Hickman and Bill Ellsworth, U.S. Geological Survey; and Lee Younker, Lawrence Livermore Laboratory. In addition to exhuming samples of fault rock and fluids from seismogenic depths, the hole will be used to make a wide range of geophysical measurements within the fault zone and to monitor the fault zone over time. Four areas along the San Andreas have been selected as candidates for deep drilling: the Mojave segment of the San Andreas between Leona Valley and Big Pine, the Carrizo Plain, the San Francisco Peninsula between Los Altos and Daly City, and the Northern Gabilan Range between the Cienga winery and Melendy Ranch. These sites were chosen from an initial list compiled at the International Fault Zone Drilling Workshop held in Asilomar, Calif., in December 1992 and at meetings held this winter and spring in Menlo Park, Calif.

  10. Selection of optimal complexity for ENSO-EMR model by minimum description length principle

    NASA Astrophysics Data System (ADS)

    Loskutov, E. M.; Mukhin, D.; Mukhina, A.; Gavrilov, A.; Kondrashov, D. A.; Feigin, A. M.

    2012-12-01

    One of the main problems arising in modeling of data taken from natural system is finding a phase space suitable for construction of the evolution operator model. Since we usually deal with strongly high-dimensional behavior, we are forced to construct a model working in some projection of system phase space corresponding to time scales of interest. Selection of optimal projection is non-trivial problem since there are many ways to reconstruct phase variables from given time series, especially in the case of a spatio-temporal data field. Actually, finding optimal projection is significant part of model selection, because, on the one hand, the transformation of data to some phase variables vector can be considered as a required component of the model. On the other hand, such an optimization of a phase space makes sense only in relation to the parametrization of the model we use, i.e. representation of evolution operator, so we should find an optimal structure of the model together with phase variables vector. In this paper we propose to use principle of minimal description length (Molkov et al., 2009) for selection models of optimal complexity. The proposed method is applied to optimization of Empirical Model Reduction (EMR) of ENSO phenomenon (Kravtsov et al. 2005, Kondrashov et. al., 2005). This model operates within a subset of leading EOFs constructed from spatio-temporal field of SST in Equatorial Pacific, and has a form of multi-level stochastic differential equations (SDE) with polynomial parameterization of the right-hand side. Optimal values for both the number of EOF, the order of polynomial and number of levels are estimated from the Equatorial Pacific SST dataset. References: Ya. Molkov, D. Mukhin, E. Loskutov, G. Fidelin and A. Feigin, Using the minimum description length principle for global reconstruction of dynamic systems from noisy time series, Phys. Rev. E, Vol. 80, P 046207, 2009 Kravtsov S, Kondrashov D, Ghil M, 2005: Multilevel regression

  11. 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.

  12. Techniques for optimal crop selection in a controlled ecological life support system

    NASA Technical Reports Server (NTRS)

    Mccormack, Ann; Finn, Cory; Dunsky, Betsy

    1993-01-01

    A Controlled Ecological Life Support System (CELSS) utilizes a plant's natural ability to regenerate air and water while being grown as a food source in a closed life support system. Current plant research is directed toward obtaining quantitative empirical data on the regenerative ability of each species of plant and the system volume and power requirements. Two techniques were adapted to optimize crop species selection while at the same time minimizing the system volume and power requirements. Each allows the level of life support supplied by the plants to be selected, as well as other system parameters. The first technique uses decision analysis in the form of a spreadsheet. The second method, which is used as a comparison with and validation of the first, utilizes standard design optimization techniques. Simple models of plant processes are used in the development of these methods.

  13. Techniques for optimal crop selection in a controlled ecological life support system

    NASA Technical Reports Server (NTRS)

    Mccormack, Ann; Finn, Cory; Dunsky, Betsy

    1992-01-01

    A Controlled Ecological Life Support System (CELSS) utilizes a plant's natural ability to regenerate air and water while being grown as a food source in a closed life support system. Current plant research is directed toward obtaining quantitative empirical data on the regenerative ability of each species of plant and the system volume and power requirements. Two techniques were adapted to optimize crop species selection while at the same time minimizing the system volume and power requirements. Each allows the level of life support supplied by the plants to be selected, as well as other system parameters. The first technique uses decision analysis in the form of a spreadsheet. The second method, which is used as a comparison with and validation of the first, utilizes standard design optimization techniques. Simple models of plant processes are used in the development of these methods.

  14. Hyperopt: a Python library for model selection and hyperparameter optimization

    NASA Astrophysics Data System (ADS)

    Bergstra, James; Komer, Brent; Eliasmith, Chris; Yamins, Dan; Cox, David D.

    2015-01-01

    Sequential model-based optimization (also known as Bayesian optimization) is one of the most efficient methods (per function evaluation) of function minimization. This efficiency makes it appropriate for optimizing the hyperparameters of machine learning algorithms that are slow to train. The Hyperopt library provides algorithms and parallelization infrastructure for performing hyperparameter optimization (model selection) in Python. This paper presents an introductory tutorial on the usage of the Hyperopt library, including the description of search spaces, minimization (in serial and parallel), and the analysis of the results collected in the course of minimization. This paper also gives an overview of Hyperopt-Sklearn, a software project that provides automatic algorithm configuration of the Scikit-learn machine learning library. Following Auto-Weka, we take the view that the choice of classifier and even the choice of preprocessing module can be taken together to represent a single large hyperparameter optimization problem. We use Hyperopt to define a search space that encompasses many standard components (e.g. SVM, RF, KNN, PCA, TFIDF) and common patterns of composing them together. We demonstrate, using search algorithms in Hyperopt and standard benchmarking data sets (MNIST, 20-newsgroups, convex shapes), that searching this space is practical and effective. In particular, we improve on best-known scores for the model space for both MNIST and convex shapes. The paper closes with some discussion of ongoing and future work.

  15. Longitudinal Antigenic Sequences and Sites from Intra-Host Evolution (LASSIE) identifies immune-selected HIV variants

    DOE PAGES

    Hraber, Peter; Korber, Bette; Wagh, Kshitij; ...

    2015-10-21

    Within-host genetic sequencing from samples collected over time provides a dynamic view of how viruses evade host immunity. Immune-driven mutations might stimulate neutralization breadth by selecting antibodies adapted to cycles of immune escape that generate within-subject epitope diversity. Comprehensive identification of immune-escape mutations is experimentally and computationally challenging. With current technology, many more viral sequences can readily be obtained than can be tested for binding and neutralization, making down-selection necessary. Typically, this is done manually, by picking variants that represent different time-points and branches on a phylogenetic tree. Such strategies are likely to miss many relevant mutations and combinations ofmore » mutations, and to be redundant for other mutations. Longitudinal Antigenic Sequences and Sites from Intrahost Evolution (LASSIE) uses transmitted founder loss to identify virus “hot-spots” under putative immune selection and chooses sequences that represent recurrent mutations in selected sites. LASSIE favors earliest sequences in which mutations arise. Here, with well-characterized longitudinal Env sequences, we confirmed selected sites were concentrated in antibody contacts and selected sequences represented diverse antigenic phenotypes. Finally, practical applications include rapidly identifying immune targets under selective pressure within a subject, selecting minimal sets of reagents for immunological assays that characterize evolving antibody responses, and for immunogens in polyvalent “cocktail” vaccines.« less

  16. Decarboxylative alkylation for site-selective bioconjugation of native proteins via oxidation potentials.

    PubMed

    Bloom, Steven; Liu, Chun; Kölmel, Dominik K; Qiao, Jennifer X; Zhang, Yong; Poss, Michael A; Ewing, William R; MacMillan, David W C

    2018-02-01

    The advent of antibody-drug conjugates as pharmaceuticals has fuelled a need for reliable methods of site-selective protein modification that furnish homogeneous adducts. Although bioorthogonal methods that use engineered amino acids often provide an elegant solution to the question of selective functionalization, achieving homogeneity using native amino acids remains a challenge. Here, we explore visible-light-mediated single-electron transfer as a mechanism towards enabling site- and chemoselective bioconjugation. Specifically, we demonstrate the use of photoredox catalysis as a platform to selectivity wherein the discrepancy in oxidation potentials between internal versus C-terminal carboxylates can be exploited towards obtaining C-terminal functionalization exclusively. This oxidation potential-gated technology is amenable to endogenous peptides and has been successfully demonstrated on the protein insulin. As a fundamentally new approach to bioconjugation this methodology provides a blueprint toward the development of photoredox catalysis as a generic platform to target other redox-active side chains for native conjugation.

  17. Decarboxylative alkylation for site-selective bioconjugation of native proteins via oxidation potentials

    NASA Astrophysics Data System (ADS)

    Bloom, Steven; Liu, Chun; Kölmel, Dominik K.; Qiao, Jennifer X.; Zhang, Yong; Poss, Michael A.; Ewing, William R.; MacMillan, David W. C.

    2018-02-01

    The advent of antibody-drug conjugates as pharmaceuticals has fuelled a need for reliable methods of site-selective protein modification that furnish homogeneous adducts. Although bioorthogonal methods that use engineered amino acids often provide an elegant solution to the question of selective functionalization, achieving homogeneity using native amino acids remains a challenge. Here, we explore visible-light-mediated single-electron transfer as a mechanism towards enabling site- and chemoselective bioconjugation. Specifically, we demonstrate the use of photoredox catalysis as a platform to selectivity wherein the discrepancy in oxidation potentials between internal versus C-terminal carboxylates can be exploited towards obtaining C-terminal functionalization exclusively. This oxidation potential-gated technology is amenable to endogenous peptides and has been successfully demonstrated on the protein insulin. As a fundamentally new approach to bioconjugation this methodology provides a blueprint toward the development of photoredox catalysis as a generic platform to target other redox-active side chains for native conjugation.

  18. Prediction of lysine glutarylation sites by maximum relevance minimum redundancy feature selection.

    PubMed

    Ju, Zhe; He, Jian-Jun

    2018-06-01

    Lysine glutarylation is new type of protein acylation modification in both prokaryotes and eukaryotes. To better understand the molecular mechanism of glutarylation, it is important to identify glutarylated substrates and their corresponding glutarylation sites accurately. In this study, a novel bioinformatics tool named GlutPred is developed to predict glutarylation sites by using multiple feature extraction and maximum relevance minimum redundancy feature selection. On the one hand, amino acid factors, binary encoding, and the composition of k-spaced amino acid pairs features are incorporated to encode glutarylation sites. And the maximum relevance minimum redundancy method and the incremental feature selection algorithm are adopted to remove the redundant features. On the other hand, a biased support vector machine algorithm is used to handle the imbalanced problem in glutarylation sites training dataset. As illustrated by 10-fold cross-validation, the performance of GlutPred achieves a satisfactory performance with a Sensitivity of 64.80%, a Specificity of 76.60%, an Accuracy of 74.90% and a Matthew's correlation coefficient of 0.3194. Feature analysis shows that some k-spaced amino acid pair features play the most important roles in the prediction of glutarylation sites. The conclusions derived from this study might provide some clues for understanding the molecular mechanisms of glutarylation. Copyright © 2018 Elsevier Inc. All rights reserved.

  19. 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.

  20. Dynamic nuclear polarization and optimal control spatial-selective 13C MRI and MRS

    NASA Astrophysics Data System (ADS)

    Vinding, Mads S.; Laustsen, Christoffer; Maximov, Ivan I.; Søgaard, Lise Vejby; Ardenkjær-Larsen, Jan H.; Nielsen, Niels Chr.

    2013-02-01

    Aimed at 13C metabolic magnetic resonance imaging (MRI) and spectroscopy (MRS) applications, we demonstrate that dynamic nuclear polarization (DNP) may be combined with optimal control 2D spatial selection to simultaneously obtain high sensitivity and well-defined spatial restriction. This is achieved through the development of spatial-selective single-shot spiral-readout MRI and MRS experiments combined with dynamic nuclear polarization hyperpolarized [1-13C]pyruvate on a 4.7 T pre-clinical MR scanner. The method stands out from related techniques by facilitating anatomic shaped region-of-interest (ROI) single metabolite signals available for higher image resolution or single-peak spectra. The 2D spatial-selective rf pulses were designed using a novel Krotov-based optimal control approach capable of iteratively fast providing successful pulse sequences in the absence of qualified initial guesses. The technique may be important for early detection of abnormal metabolism, monitoring disease progression, and drug research.

  1. SVM-RFE based feature selection and Taguchi parameters optimization for multiclass SVM classifier.

    PubMed

    Huang, Mei-Ling; Hung, Yung-Hsiang; Lee, W M; Li, R K; Jiang, Bo-Ru

    2014-01-01

    Recently, support vector machine (SVM) has excellent performance on classification and prediction and is widely used on disease diagnosis or medical assistance. However, SVM only functions well on two-group classification problems. This study combines feature selection and SVM recursive feature elimination (SVM-RFE) to investigate the classification accuracy of multiclass problems for Dermatology and Zoo databases. Dermatology dataset contains 33 feature variables, 1 class variable, and 366 testing instances; and the Zoo dataset contains 16 feature variables, 1 class variable, and 101 testing instances. The feature variables in the two datasets were sorted in descending order by explanatory power, and different feature sets were selected by SVM-RFE to explore classification accuracy. Meanwhile, Taguchi method was jointly combined with SVM classifier in order to optimize parameters C and γ to increase classification accuracy for multiclass classification. The experimental results show that the classification accuracy can be more than 95% after SVM-RFE feature selection and Taguchi parameter optimization for Dermatology and Zoo databases.

  2. SVM-RFE Based Feature Selection and Taguchi Parameters Optimization for Multiclass SVM Classifier

    PubMed Central

    Huang, Mei-Ling; Hung, Yung-Hsiang; Lee, W. M.; Li, R. K.; Jiang, Bo-Ru

    2014-01-01

    Recently, support vector machine (SVM) has excellent performance on classification and prediction and is widely used on disease diagnosis or medical assistance. However, SVM only functions well on two-group classification problems. This study combines feature selection and SVM recursive feature elimination (SVM-RFE) to investigate the classification accuracy of multiclass problems for Dermatology and Zoo databases. Dermatology dataset contains 33 feature variables, 1 class variable, and 366 testing instances; and the Zoo dataset contains 16 feature variables, 1 class variable, and 101 testing instances. The feature variables in the two datasets were sorted in descending order by explanatory power, and different feature sets were selected by SVM-RFE to explore classification accuracy. Meanwhile, Taguchi method was jointly combined with SVM classifier in order to optimize parameters C and γ to increase classification accuracy for multiclass classification. The experimental results show that the classification accuracy can be more than 95% after SVM-RFE feature selection and Taguchi parameter optimization for Dermatology and Zoo databases. PMID:25295306

  3. Parameter Selection and Performance Comparison of Particle Swarm Optimization in Sensor Networks Localization.

    PubMed

    Cui, Huanqing; Shu, Minglei; Song, Min; Wang, Yinglong

    2017-03-01

    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.

  4. 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

  5. An optimized magnetite microparticle-based phosphopeptide enrichment strategy for identifying multiple phosphorylation sites in an immunoprecipitated protein.

    PubMed

    Huang, Yi; Shi, Qihui; Tsung, Chia-Kuang; Gunawardena, Harsha P; Xie, Ling; Yu, Yanbao; Liang, Hongjun; Yang, Pengyuan; Stucky, Galen D; Chen, Xian

    2011-01-01

    To further improve the selectivity and throughput of phosphopeptide analysis for the samples from real-time cell lysates, here we demonstrate a highly efficient method for phosphopeptide enrichment via newly synthesized magnetite microparticles and the concurrent mass spectrometric analysis. The magnetite microparticles show excellent magnetic responsivity and redispersibility for a quick enrichment of those phosphopeptides in solution. The selectivity and sensitivity of magnetite microparticles in phosphopeptide enrichment are first evaluated by a known mixture containing both phosphorylated and nonphosphorylated proteins. Compared with the titanium dioxide-coated magnetic beads commercially available, our magnetite microparticles show a better specificity toward phosphopeptides. The selectively-enriched phosphopeptides from tryptic digests of β-casein can be detected down to 0.4 fmol μl⁻¹, whereas the recovery efficiency is approximately 90% for monophosphopeptides. This magnetite microparticle-based affinity technology with optimized enrichment conditions is then immediately applied to identify all possible phosphorylation sites on a signal protein isolated in real time from a stress-stimulated mammalian cell culture. A large fraction of peptides eluted from the magnetic particle enrichment step were identified and characterized as either single- or multiphosphorylated species by tandem mass spectrometry. With their high efficiency and utility for phosphopeptide enrichment, the magnetite microparticles hold great potential in the phosphoproteomic studies on real-time samples from cell lysates. Published by Elsevier Inc.

  6. SELECTING LEAST-DISTURBED SURVEY SITES FOR GREAT PLAINS STREAMS AND RIVERS

    EPA Science Inventory

    True reference condition probably does not exist for streams in highly utilized regions such as the Great Plains. Selecting least-disturbed sites for large regions is confounded by the association between human uses and natural gradients, and by multiple kinds of disturbance. U...

  7. 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

  8. Optimal networks of future gravitational-wave telescopes

    NASA Astrophysics Data System (ADS)

    Raffai, Péter; Gondán, László; Heng, Ik Siong; Kelecsényi, Nándor; Logue, Josh; Márka, Zsuzsa; Márka, Szabolcs

    2013-08-01

    We aim to find the optimal site locations for a hypothetical network of 1-3 triangular gravitational-wave telescopes. We define the following N-telescope figures of merit (FoMs) and construct three corresponding metrics: (a) capability of reconstructing the signal polarization; (b) accuracy in source localization; and (c) accuracy in reconstructing the parameters of a standard binary source. We also define a combined metric that takes into account the three FoMs with practically equal weight. After constructing a geomap of possible telescope sites, we give the optimal 2-telescope networks for the four FoMs separately in example cases where the location of the first telescope has been predetermined. We found that based on the combined metric, placing the first telescope to Australia provides the most options for optimal site selection when extending the network with a second instrument. We suggest geographical regions where a potential second and third telescope could be placed to get optimal network performance in terms of our FoMs. Additionally, we use a similar approach to find the optimal location and orientation for the proposed LIGO-India detector within a five-detector network with Advanced LIGO (Hanford), Advanced LIGO (Livingston), Advanced Virgo, and KAGRA. We found that the FoMs do not change greatly in sites within India, though the network can suffer a significant loss in reconstructing signal polarizations if the orientation angle of an L-shaped LIGO-India is not set to the optimal value of ˜58.2°( + k × 90°) (measured counterclockwise from East to the bisector of the arms).

  9. Portfolio optimization for seed selection in diverse weather scenarios.

    PubMed

    Marko, Oskar; Brdar, Sanja; Panić, Marko; Šašić, Isidora; Despotović, Danica; Knežević, Milivoje; Crnojević, Vladimir

    2017-01-01

    The aim of this work was to develop a method for selection of optimal soybean varieties for the American Midwest using data analytics. We extracted the knowledge about 174 varieties from the dataset, which contained information about weather, soil, yield and regional statistical parameters. Next, we predicted the yield of each variety in each of 6,490 observed subregions of the Midwest. Furthermore, yield was predicted for all the possible weather scenarios approximated by 15 historical weather instances contained in the dataset. Using predicted yields and covariance between varieties through different weather scenarios, we performed portfolio optimisation. In this way, for each subregion, we obtained a selection of varieties, that proved superior to others in terms of the amount and stability of yield. According to the rules of Syngenta Crop Challenge, for which this research was conducted, we aggregated the results across all subregions and selected up to five soybean varieties that should be distributed across the network of seed retailers. The work presented in this paper was the winning solution for Syngenta Crop Challenge 2017.

  10. Portfolio optimization for seed selection in diverse weather scenarios

    PubMed Central

    Brdar, Sanja; Panić, Marko; Šašić, Isidora; Despotović, Danica; Knežević, Milivoje; Crnojević, Vladimir

    2017-01-01

    The aim of this work was to develop a method for selection of optimal soybean varieties for the American Midwest using data analytics. We extracted the knowledge about 174 varieties from the dataset, which contained information about weather, soil, yield and regional statistical parameters. Next, we predicted the yield of each variety in each of 6,490 observed subregions of the Midwest. Furthermore, yield was predicted for all the possible weather scenarios approximated by 15 historical weather instances contained in the dataset. Using predicted yields and covariance between varieties through different weather scenarios, we performed portfolio optimisation. In this way, for each subregion, we obtained a selection of varieties, that proved superior to others in terms of the amount and stability of yield. According to the rules of Syngenta Crop Challenge, for which this research was conducted, we aggregated the results across all subregions and selected up to five soybean varieties that should be distributed across the network of seed retailers. The work presented in this paper was the winning solution for Syngenta Crop Challenge 2017. PMID:28863173

  11. 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...

  12. Hot Spots on the Web for Teacher Librarians: A Selection of Recommended Web Sites for TLs To Visit.

    ERIC Educational Resources Information Center

    1996

    Six papers review and recommend sites on the Web as resources for teacher librarians include: "Just Do It: A Guide to Getting Out There and Doing It Yourself" (Catherine Ryan); "A Selection of Recommended Web Sites for TLs To Visit" (Karen Bonanno); "A Selection of Recommended Web Sites for TLs To Visit" (Sandra…

  13. 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. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Optimization of multi-environment trials for genomic selection based on crop models.

    PubMed

    Rincent, R; Kuhn, E; Monod, H; Oury, F-X; Rousset, M; Allard, V; Le Gouis, J

    2017-08-01

    We propose a statistical criterion to optimize multi-environment trials to predict genotype × environment interactions more efficiently, by combining crop growth models and genomic selection models. Genotype × environment interactions (GEI) are common in plant multi-environment trials (METs). In this context, models developed for genomic selection (GS) that refers to the use of genome-wide information for predicting breeding values of selection candidates need to be adapted. One promising way to increase prediction accuracy in various environments is to combine ecophysiological and genetic modelling thanks to crop growth models (CGM) incorporating genetic parameters. The efficiency of this approach relies on the quality of the parameter estimates, which depends on the environments composing this MET used for calibration. The objective of this study was to determine a method to optimize the set of environments composing the MET for estimating genetic parameters in this context. A criterion called OptiMET was defined to this aim, and was evaluated on simulated and real data, with the example of wheat phenology. The MET defined with OptiMET allowed estimating the genetic parameters with lower error, leading to higher QTL detection power and higher prediction accuracies. MET defined with OptiMET was on average more efficient than random MET composed of twice as many environments, in terms of quality of the parameter estimates. OptiMET is thus a valuable tool to determine optimal experimental conditions to best exploit MET and the phenotyping tools that are currently developed.

  15. Public concerns about and perceptions of solid waste dump sites and selection of sanitary landfill sites in the West Bank, Palestinian territory.

    PubMed

    Al-Khatib, Issam A; Abu Hammad, Ahmad; Sharkas, Othman A; Sato, Chikashi

    2015-04-01

    Palestinian inhabitants have disposed of their solid wastes at open dumpsites over the past 40 years without an adequate solid waste management (SWM) plans. Recently, the Palestinian Authority initiated SWM planning to establish controlled sanitary landfills, based on a participatory approach. The purpose of this study was to assess public concerns about existing solid waste dumpsites and public perceptions of sanitary landfill site selection. The study will also take into consideration the effect of diverse social, economic, and environmental related factors of the inhabitants on sitting suitable landfill sites in three Palestinian districts in the West Bank, namely, "Nablus," "Salfit," and "Ramallah and Al-Bireh." The results of this study showed that 64.9% of the sample population are aware of the problems and potential impacts associated with random dumpsites, and 41.6% think that they are suffering from the dumps. Among the environmental, socioeconomic, and political factors, the environmental factors, air pollution in particular, are thought be the most important consideration in selecting a landfill site. The "fairness in selecting a landfill site" was chosen to be one of the most important socioeconomic factors, possibly as a reaction to the Israeli occupation and subsequent land use restrictions in the West Bank, Palestinian territory.

  16. Optimal Reference Gene Selection for Expression Studies in Human Reticulocytes.

    PubMed

    Aggarwal, Anu; Jamwal, Manu; Viswanathan, Ganesh K; Sharma, Prashant; Sachdeva, ManUpdesh S; Bansal, Deepak; Malhotra, Pankaj; Das, Reena

    2018-05-01

    Reference genes are indispensable for normalizing mRNA levels across samples in real-time quantitative PCR. Their expression levels vary under different experimental conditions and because of several inherent characteristics. Appropriate reference gene selection is thus critical for gene-expression studies. This study aimed at selecting optimal reference genes for gene-expression analysis of reticulocytes and at validating them in hereditary spherocytosis (HS) and β-thalassemia intermedia (βTI) patients. Seven reference genes (PGK1, MPP1, HPRT1, ACTB, GAPDH, RN18S1, and SDHA) were selected because of published reports. Real-time quantitative PCR was performed on reticulocytes in 20 healthy volunteers, 15 HS patients, and 10 βTI patients. Threshold cycle values were compared with fold-change method and RefFinder software. The stable reference genes recommended by RefFinder were validated with SLC4A1 and flow cytometric eosin-5'-maleimide binding assay values in HS patients and HBG2 and high performance liquid chromatography-derived percentage of hemoglobin F in βTI. Comprehensive ranking predicted MPP1 and GAPDH as optimal reference genes for reticulocytes that were not affected in HS and βTI. This was further confirmed on validation with eosin-5'-maleimide results and percentage of hemoglobin F in HS and βTI patients, respectively. Hence, MPP1 and GAPDH are good reference genes for reticulocyte expression studies compared with ACTB and RN18S1, the two most commonly used reference genes. Copyright © 2018 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  17. Ventrogluteal versus dorsogluteal site selection: A cross-sectional study of muscle and subcutaneous fat thicknesses and an algorithm incorporating demographic and anthropometric data to predict injection outcome.

    PubMed

    Larkin, Theresa A; Ashcroft, Elfriede; Elgellaie, Asmahan; Hickey, Blake A

    2017-06-01

    . Female gender, and waist and hip circumference were significant predictors of subcutaneous fat thickness at both sites; male gender was a significant predictor of dorsogluteal site muscle thickness (all p<0.05). In the algorithm developed for site selection based on theoretical injection outcome, the best discriminators were: weight, BMI and waist circumference for females, and weight and distance between the iliac tubercle and anterior superior iliac spine for males. The algorithm describes when each of the ventrogluteal and dorsogluteal sites is appropriate or should be avoided, based on easily obtained anthropometric data. This has direct relevance in clinical practice in evidence-based site selection for gluteal intramuscular injections for optimal medication and health outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Variation at the DRD4 locus is associated with wariness and local site selection in urban black swans.

    PubMed

    van Dongen, Wouter F D; Robinson, Randall W; Weston, Michael A; Mulder, Raoul A; Guay, Patrick-Jean

    2015-12-11

    Interactions between wildlife and humans are increasing. Urban animals are often less wary of humans than their non-urban counterparts, which could be explained by habituation, adaptation or local site selection. Under local site selection, individuals that are less tolerant of humans are less likely to settle in urban areas. However, there is little evidence for such temperament-based site selection, and even less is known about its underlying genetic basis. We tested whether site selection in urban and non-urban habitats by black swans (Cygnus atratus) was associated with polymorphisms in two genes linked to fear in animals, the dopamine receptor D4 (DRD4) and serotonin transporter (SERT) genes. Wariness in swans was highly repeatable between disturbance events (repeatability = 0.61) and non-urban swans initiated escape from humans earlier than urban swans. We found no inter-individual variation in the SERT gene, but identified five DRD4 genotypes and an association between DRD4 genotype and wariness. Individuals possessing the most common DRD4 genotype were less wary than individuals possessing rarer genotypes. As predicted by the local site selection hypothesis, genotypes associated with wary behaviour were over three times more frequent at the non-urban site. This resulted in moderate population differentiation at DRD4 (FST = 0.080), despite the sites being separated by only 30 km, a short distance for this highly-mobile species. Low population differentiation at neutrally-selected microsatellite loci and the likely occasional migration of swans between the populations reduces the likelihood of local site adaptations. Our results suggest that wariness in swans is partly genetically-determined and that wary swans settle in less-disturbed areas. More generally, our findings suggest that site-specific management strategies may be necessary that consider the temperament of local animals.

  19. Dynamic reserve selection: Optimal land retention with land-price feedbacks

    Treesearch

    Sandor F. Toth; Robert G. Haight; Luke W. Rogers

    2011-01-01

    Urban growth compromises open space and ecosystem functions. To mitigate the negative effects, some agencies use reserve selection models to identify conservation sites for purchase or retention. Existing models assume that conservation has no impact on nearby land prices. We propose a new integer program that relaxes this assumption via adaptive cost coefficients. Our...

  20. A reliable computational workflow for the selection of optimal screening libraries.

    PubMed

    Gilad, Yocheved; Nadassy, Katalin; Senderowitz, Hanoch

    2015-01-01

    The experimental screening of compound collections is a common starting point in many drug discovery projects. Successes of such screening campaigns critically depend on the quality of the screened library. Many libraries are currently available from different vendors yet the selection of the optimal screening library for a specific project is challenging. We have devised a novel workflow for the rational selection of project-specific screening libraries. The workflow accepts as input a set of virtual candidate libraries and applies the following steps to each library: (1) data curation; (2) assessment of ADME/T profile; (3) assessment of the number of promiscuous binders/frequent HTS hitters; (4) assessment of internal diversity; (5) assessment of similarity to known active compound(s) (optional); (6) assessment of similarity to in-house or otherwise accessible compound collections (optional). For ADME/T profiling, Lipinski's and Veber's rule-based filters were implemented and a new blood brain barrier permeation model was developed and validated (85 and 74 % success rate for training set and test set, respectively). Diversity and similarity descriptors which demonstrated best performances in terms of their ability to select either diverse or focused sets of compounds from three databases (Drug Bank, CMC and CHEMBL) were identified and used for diversity and similarity assessments. The workflow was used to analyze nine common screening libraries available from six vendors. The results of this analysis are reported for each library providing an assessment of its quality. Furthermore, a consensus approach was developed to combine the results of these analyses into a single score for selecting the optimal library under different scenarios. We have devised and tested a new workflow for the rational selection of screening libraries under different scenarios. The current workflow was implemented using the Pipeline Pilot software yet due to the usage of generic

  1. Conformational exchange of aromatic side chains characterized by L-optimized TROSY-selected ¹³C CPMG relaxation dispersion.

    PubMed

    Weininger, Ulrich; Respondek, Michal; Akke, Mikael

    2012-09-01

    Protein dynamics on the millisecond time scale commonly reflect conformational transitions between distinct functional states. NMR relaxation dispersion experiments have provided important insights into biologically relevant dynamics with site-specific resolution, primarily targeting the protein backbone and methyl-bearing side chains. Aromatic side chains represent attractive probes of protein dynamics because they are over-represented in protein binding interfaces, play critical roles in enzyme catalysis, and form an important part of the core. Here we introduce a method to characterize millisecond conformational exchange of aromatic side chains in selectively (13)C labeled proteins by means of longitudinal- and transverse-relaxation optimized CPMG relaxation dispersion. By monitoring (13)C relaxation in a spin-state selective manner, significant sensitivity enhancement can be achieved in terms of both signal intensity and the relative exchange contribution to transverse relaxation. Further signal enhancement results from optimizing the longitudinal relaxation recovery of the covalently attached (1)H spins. We validated the L-TROSY-CPMG experiment by measuring fast folding-unfolding kinetics of the small protein CspB under native conditions. The determined unfolding rate matches perfectly with previous results from stopped-flow kinetics. The CPMG-derived chemical shift differences between the folded and unfolded states are in excellent agreement with those obtained by urea-dependent chemical shift analysis. The present method enables characterization of conformational exchange involving aromatic side chains and should serve as a valuable complement to methods developed for other types of protein side chains.

  2. Breeding site selection by coho salmon (Oncorhynchus kisutch) in relation to large wood additions and factors that influence reproductive success

    USGS Publications Warehouse

    Clark, Steven M.; Dunham, Jason B.; McEnroe, Jeffery R.; Lightcap, Scott W.

    2014-01-01

    The fitness of female Pacific salmon (Oncorhynchus spp.) with respect to breeding behavior can be partitioned into at least four fitness components: survival to reproduction, competition for breeding sites, success of egg incubation, and suitability of the local environment near breeding sites for early rearing of juveniles. We evaluated the relative influences of habitat features linked to these fitness components with respect to selection of breeding sites by coho salmon (Oncorhynchus kisutch). We also evaluated associations between breeding site selection and additions of large wood, as the latter were introduced into the study system as a means of restoring habitat conditions to benefit coho salmon. We used a model selection approach to organize specific habitat features into groupings reflecting fitness components and influences of large wood. Results of this work suggest that female coho salmon likely select breeding sites based on a wide range of habitat features linked to all four hypothesized fitness components. More specifically, model parameter estimates indicated that breeding site selection was most strongly influenced by proximity to pool-tail crests and deeper water (mean and maximum depths). Linkages between large wood and breeding site selection were less clear. Overall, our findings suggest that breeding site selection by coho salmon is influenced by a suite of fitness components in addition to the egg incubation environment, which has been the emphasis of much work in the past.

  3. Site-selective protein-modification chemistry for basic biology and drug development.

    PubMed

    Krall, Nikolaus; da Cruz, Filipa P; Boutureira, Omar; Bernardes, Gonçalo J L

    2016-02-01

    Nature has produced intricate machinery to covalently diversify the structure of proteins after their synthesis in the ribosome. In an attempt to mimic nature, chemists have developed a large set of reactions that enable post-expression modification of proteins at pre-determined sites. These reactions are now used to selectively install particular modifications on proteins for many biological and therapeutic applications. For example, they provide an opportunity to install post-translational modifications on proteins to determine their exact biological roles. Labelling of proteins in live cells with fluorescent dyes allows protein uptake and intracellular trafficking to be tracked and also enables physiological parameters to be measured optically. Through the conjugation of potent cytotoxicants to antibodies, novel anti-cancer drugs with improved efficacy and reduced side effects may be obtained. In this Perspective, we highlight the most exciting current and future applications of chemical site-selective protein modification and consider which hurdles still need to be overcome for more widespread use.

  4. Site-selective protein-modification chemistry for basic biology and drug development

    NASA Astrophysics Data System (ADS)

    Krall, Nikolaus; da Cruz, Filipa P.; Boutureira, Omar; Bernardes, Gonçalo J. L.

    2016-02-01

    Nature has produced intricate machinery to covalently diversify the structure of proteins after their synthesis in the ribosome. In an attempt to mimic nature, chemists have developed a large set of reactions that enable post-expression modification of proteins at pre-determined sites. These reactions are now used to selectively install particular modifications on proteins for many biological and therapeutic applications. For example, they provide an opportunity to install post-translational modifications on proteins to determine their exact biological roles. Labelling of proteins in live cells with fluorescent dyes allows protein uptake and intracellular trafficking to be tracked and also enables physiological parameters to be measured optically. Through the conjugation of potent cytotoxicants to antibodies, novel anti-cancer drugs with improved efficacy and reduced side effects may be obtained. In this Perspective, we highlight the most exciting current and future applications of chemical site-selective protein modification and consider which hurdles still need to be overcome for more widespread use.

  5. NASA Parts Selection List (NPSL) WWW Site http://nepp.nasa.gov/npsl

    NASA Technical Reports Server (NTRS)

    Brusse, Jay

    2000-01-01

    The NASA Parts Selection List (NPSL) is an on-line resource for electronic parts selection tailored for use by spaceflight projects. The NPSL provides a list of commonly used electronic parts that have a history of satisfactory use in spaceflight applications. The objective of this www site is to provide NASA projects, contractors, university experimenters, et al with an easy to use resource that provides a baseline of electronic parts from which designers are encouraged to select. The NPSL is an ongoing resource produced by Code 562 in support of the NASA HQ funded NASA Electronic Parts and Packaging (NEPP) Program. The NPSL is produced as an electronic format deliverable made available via the referenced www site administered by Code 562. The NPSL does not provide information pertaining to patented or proprietary information. All of the information contained in the NPSL is available through various other public domain resources such as US Military procurement specifications for electronic parts, NASA GSFC's Preferred Parts List (PPL-21), and NASA's Standard Parts List (MIL-STD975).

  6. The analysis of distribution of meteorological over China in astronomical site selection

    NASA Astrophysics Data System (ADS)

    Zhang, Cai-yun; Weng, Ning-quan

    2014-02-01

    The distribution of parameters such as sunshine hours, precipitation, and visibility were obtained by analyzing the meteorological data in 906 stations of China during 1981~2012. And the month and annual variations of the parameters in some typical stations were discussed. The results show that: (1) the distribution of clear days is similar to that of sunshine hours, the values of which decrease from north to south and from west to east. The distributions of cloud, precipitation and vapor pressure are opposite. (2) The northwest areas in China have the characteristic such as low precipitation and vapor pressure, small cloud clever, and good visibility, which are the general conditions of astronomical site selection. (3) The parameters have obvious month variation. There are large precipitation, long sunshine hours and strong radiation in the mid months of one year, which are opposite in beginning and ending of one year. (4) In the selected stations, the value of vapor pressure decreases year by year, and the optical depth is similar or invariable. All the above results provided for astronomical site selection.

  7. Electrode channel selection based on backtracking search optimization in motor imagery brain-computer interfaces.

    PubMed

    Dai, Shengfa; Wei, Qingguo

    2017-01-01

    Common spatial pattern algorithm is widely used to estimate spatial filters in motor imagery based brain-computer interfaces. However, use of a large number of channels will make common spatial pattern tend to over-fitting and the classification of electroencephalographic signals time-consuming. To overcome these problems, it is necessary to choose an optimal subset of the whole channels to save computational time and improve the classification accuracy. In this paper, a novel method named backtracking search optimization algorithm is proposed to automatically select the optimal channel set for common spatial pattern. Each individual in the population is a N-dimensional vector, with each component representing one channel. A population of binary codes generate randomly in the beginning, and then channels are selected according to the evolution of these codes. The number and positions of 1's in the code denote the number and positions of chosen channels. The objective function of backtracking search optimization algorithm is defined as the combination of classification error rate and relative number of channels. Experimental results suggest that higher classification accuracy can be achieved with much fewer channels compared to standard common spatial pattern with whole channels.

  8. Chiral stationary phase optimized selectivity liquid chromatography: A strategy for the separation of chiral isomers.

    PubMed

    Hegade, Ravindra Suryakant; De Beer, Maarten; Lynen, Frederic

    2017-09-15

    Chiral Stationary-Phase Optimized Selectivity Liquid Chromatography (SOSLC) is proposed as a tool to optimally separate mixtures of enantiomers on a set of commercially available coupled chiral columns. This approach allows for the prediction of the separation profiles on any possible combination of the chiral stationary phases based on a limited number of preliminary analyses, followed by automated selection of the optimal column combination. Both the isocratic and gradient SOSLC approach were implemented for prediction of the retention times for a mixture of 4 chiral pairs on all possible combinations of the 5 commercial chiral columns. Predictions in isocratic and gradient mode were performed with a commercially available and with an in-house developed Microsoft visual basic algorithm, respectively. Optimal predictions in the isocratic mode required the coupling of 4 columns whereby relative deviations between the predicted and experimental retention times ranged between 2 and 7%. Gradient predictions led to the coupling of 3 chiral columns allowing baseline separation of all solutes, whereby differences between predictions and experiments ranged between 0 and 12%. The methodology is a novel tool allowing optimizing the separation of mixtures of optical isomers. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Ion Selectivity in the KcsA Potassium Channel from the Perspective of the Ion Binding Site

    PubMed Central

    Dixit, Purushottam D.; Merchant, Safir; Asthagiri, D.

    2009-01-01

    To understand the thermodynamic exclusion of Na+ relative to K+ from the S2 site of the selectivity filter, the distribution PX(ɛ) (X = K+ or Na+) of the binding energy (ɛ) of the ion with the channel is analyzed using the potential distribution theorem. By expressing the excess chemical potential of the ion as a sum of mean-field 〈ɛ〉 and fluctuation μexflux,X contributions, we find that selectivity arises from a higher value of μflux,Na+ex relative to μflux,K+ex. To understand the role of site-site interactions on μexflux,X, we decompose PX(ɛ) into n-dependent distributions, where n is the number of ion-coordinating ligands within a distance λ from the ion. For λ comparable to typical ion-oxygen bond distances, investigations building on this multistate model reveal an inverse correlation between favorable ion-site and site-site interactions: the ion-coordination states that most influence the thermodynamics of the ion are also those for which the binding site is energetically less strained and vice versa. This correlation motivates understanding entropic effects in ion binding to the site and leads to the finding that μexflux,X is directly proportional to the average site-site interaction energy, a quantity that is sensitive to the chemical type of the ligand coordinating the ion. Increasing the coordination number around Na+ only partially accounts for the observed magnitude of selectivity; acknowledging the chemical type of the ion-coordinating ligand is essential. PMID:19289040

  10. Factors influencing clinical trial site selection in Europe: the Survey of Attitudes towards Trial sites in Europe (the SAT-EU Study).

    PubMed

    Gehring, Marta; Taylor, Rod S; Mellody, Marie; Casteels, Brigitte; Piazzi, Angela; Gensini, Gianfranco; Ambrosio, Giuseppe

    2013-11-15

    Applications to run clinical trials in Europe fell 25% between 2007 and 2011. Costs, speed of approvals and shortcomings of European Clinical Trial Directive are commonly invoked to explain this unsatisfactory performance. However, no hard evidence is available on the actual weight of these factors or has it been previously investigated whether other criteria may also impact clinical trial site selection. The Survey of Attitudes towards Trial sites in Europe (SAT-EU Study) was an anonymous, cross-sectional web-based survey that systematically assessed factors impacting European clinical trial site selection. It explored 19 factors across investigator-driven, hospital-driven and environment-driven criteria, and costs. It also surveyed perceptions of the European trial environment. Clinical research organisations (CROs), academic clinical trial units (CTUs) and industry invited to respond. weight assigned to each factor hypothesised to impact trial site selection and trial incidence. Secondary outcome: desirability of European countries to run clinical trials. Responses were obtained from 485 professionals in 34 countries: 49% from BioPharma, 40% from CTUs or CROs. Investigator-dependent, environment-dependent and hospital-dependent factors were rated highly important, costs being less important (p<0.0001). Within environment-driven criteria, pool of eligible patients, speed of approvals and presence of disease-management networks were significantly more important than costs or government financial incentives (p<0.0001). The pattern of response was consistent across respondent groupings (CTU vs CRO vs industry). Considerable variability was demonstrated in the perceived receptivity of countries to undertake clinical trials, with Germany, the UK and the Netherlands rated the best trial markets (p<0.0001). Investigator-dependent factors and ease of approval dominate trial site selection, while costs appear less important. Fostering competitiveness of European clinical

  11. Applications of the Renewable Energy Network Optimization Tool

    NASA Astrophysics Data System (ADS)

    Alliss, R.; Link, R.; Apling, D.; Kiley, H.; Mason, M.; Darmenova, K.

    2010-12-01

    As the renewable energy industry continues to grow so does the requirement for atmospheric modeling and analysis tools to maximize both wind and solar power. Renewable energy generation is variable however; presenting challenges for electrical grid operation and requires a variety of measures to adequately firm power. These measures include the production of non-renewable generation during times when renewables are not available. One strategy for minimizing the variability of renewable energy production is site diversity. Assuming that a network of renewable energy systems feed a common electrical grid, site diversity ensures that when one system on the network has a reduction in generation others on the same grid make up the difference. The site-diversity strategy can be used to mitigate the intermittency in alternative energy production systems while still maximizing saleable energy. The Renewable Energy Network Optimization Tool (ReNOT) has recently been developed to study the merits of site optimization for wind farms. The modeling system has a plug-in architecture that allows us to accommodate a wide variety of renewable energy system designs and performance metrics. The Weather Research and Forecasting (WRF) mesoscale model is applied to generate high-resolution wind databases to support the site selection of wind farms. These databases are generated on High Performance Computing systems such as the Rocky Mountain Supercomputing Center (RMSC). The databases are then accessed by ReNOT and an optimized site selection is developed. We can accommodate numerous constraints (e.g., number of sites, the geographic extent of the optimization, proximity to high-voltage transport lines, etc.). As part of our collaboration with RMSC and the State of Montana a study was performed to estimate the optimal locations of a network of wind farms. Comparisons were made to four existing wind farm locations in Montana including Glacier with a 210 MW name plate capacity, Horseshoe

  12. Selecting at-risk populations for sexually transmitted disease/HIV intervention studies.

    PubMed

    Wu, Zunyou; Rotheram-Borus, Mary Jane; Detels, Roger; Li, Li; Guan, Jihui; Liang, Guojun; Yap, Lorraine

    2007-12-01

    This paper describes one option to select populations for randomized, controlled trials (RCT). We used a popular opinion leader intervention in Fuzhou, China, to: (1) identify population selection criteria; (2) systematically examine the suitability of potential target populations and settings; (3) briefly evaluate risk and stability in the population; and (4) evaluate regional and organizational support among administrators and government officials. After comparing migrant villagers, truck drivers, factory workers, construction workers, and market employees in five regions of China, market employees in Fuzhou were identified as the optimal target population. Markets were the optimal sites for several reasons: (1) the population demonstrated a sufficient base rate of sexually transmitted diseases; (2) the population was stable over time; (3) a sufficient number of sites of manageable sizes were available; (4) stable networks existed; (5) local gatekeepers/stakeholders supported the intervention; (6) there was organizational capacity in the local health department to mount the intervention; (7) the demographic profile was similar across potential sites; and (8) the sites were sufficiently distanced to minimize contamination. Evaluating intervention efficacy in an RCT requires a time-consuming and rigorous process that systematically and routinely documents selection criteria, evaluates multiple populations, sites, and organizations for their appropriateness.

  13. Construction of a directed hammerhead ribozyme library: towards the identification of optimal target sites for antisense-mediated gene inhibition.

    PubMed Central

    Pierce, M L; Ruffner, D E

    1998-01-01

    Antisense-mediated gene inhibition uses short complementary DNA or RNA oligonucleotides to block expression of any mRNA of interest. A key parameter in the success or failure of an antisense therapy is the identification of a suitable target site on the chosen mRNA. Ultimately, the accessibility of the target to the antisense agent determines target suitability. Since accessibility is a function of many complex factors, it is currently beyond our ability to predict. Consequently, identification of the most effective target(s) requires examination of every site. Towards this goal, we describe a method to construct directed ribozyme libraries against any chosen mRNA. The library contains nearly equal amounts of ribozymes targeting every site on the chosen transcript and the library only contains ribozymes capable of binding to that transcript. Expression of the ribozyme library in cultured cells should allow identification of optimal target sites under natural conditions, subject to the complexities of a fully functional cell. Optimal target sites identified in this manner should be the most effective sites for therapeutic intervention. PMID:9801305

  14. An improved swarm optimization for parameter estimation and biological model selection.

    PubMed

    Abdullah, Afnizanfaizal; Deris, Safaai; Mohamad, Mohd Saberi; Anwar, Sohail

    2013-01-01

    One of the key aspects of computational systems biology is the investigation on the dynamic biological processes within cells. Computational models are often required to elucidate the mechanisms and principles driving the processes because of the nonlinearity and complexity. The models usually incorporate a set of parameters that signify the physical properties of the actual biological systems. In most cases, these parameters are estimated by fitting the model outputs with the corresponding experimental data. However, this is a challenging task because the available experimental data are frequently noisy and incomplete. In this paper, a new hybrid optimization method is proposed to estimate these parameters from the noisy and incomplete experimental data. The proposed method, called Swarm-based Chemical Reaction Optimization, integrates the evolutionary searching strategy employed by the Chemical Reaction Optimization, into the neighbouring searching strategy of the Firefly Algorithm method. The effectiveness of the method was evaluated using a simulated nonlinear model and two biological models: synthetic transcriptional oscillators, and extracellular protease production models. The results showed that the accuracy and computational speed of the proposed method were better than the existing Differential Evolution, Firefly Algorithm and Chemical Reaction Optimization methods. The reliability of the estimated parameters was statistically validated, which suggests that the model outputs produced by these parameters were valid even when noisy and incomplete experimental data were used. Additionally, Akaike Information Criterion was employed to evaluate the model selection, which highlighted the capability of the proposed method in choosing a plausible model based on the experimental data. In conclusion, this paper presents the effectiveness of the proposed method for parameter estimation and model selection problems using noisy and incomplete experimental data. This

  15. An Improved Swarm Optimization for Parameter Estimation and Biological Model Selection

    PubMed Central

    Abdullah, Afnizanfaizal; Deris, Safaai; Mohamad, Mohd Saberi; Anwar, Sohail

    2013-01-01

    One of the key aspects of computational systems biology is the investigation on the dynamic biological processes within cells. Computational models are often required to elucidate the mechanisms and principles driving the processes because of the nonlinearity and complexity. The models usually incorporate a set of parameters that signify the physical properties of the actual biological systems. In most cases, these parameters are estimated by fitting the model outputs with the corresponding experimental data. However, this is a challenging task because the available experimental data are frequently noisy and incomplete. In this paper, a new hybrid optimization method is proposed to estimate these parameters from the noisy and incomplete experimental data. The proposed method, called Swarm-based Chemical Reaction Optimization, integrates the evolutionary searching strategy employed by the Chemical Reaction Optimization, into the neighbouring searching strategy of the Firefly Algorithm method. The effectiveness of the method was evaluated using a simulated nonlinear model and two biological models: synthetic transcriptional oscillators, and extracellular protease production models. The results showed that the accuracy and computational speed of the proposed method were better than the existing Differential Evolution, Firefly Algorithm and Chemical Reaction Optimization methods. The reliability of the estimated parameters was statistically validated, which suggests that the model outputs produced by these parameters were valid even when noisy and incomplete experimental data were used. Additionally, Akaike Information Criterion was employed to evaluate the model selection, which highlighted the capability of the proposed method in choosing a plausible model based on the experimental data. In conclusion, this paper presents the effectiveness of the proposed method for parameter estimation and model selection problems using noisy and incomplete experimental data. This

  16. Marine turtles are not fussy nesters: a novel test of small-scale nest site selection using structure from motion beach terrain information

    PubMed Central

    Leon, Javier X.; Gilby, Ben L.; Olds, Andrew D.; Schlacher, Thomas A.

    2017-01-01

    Background Nest selection is widely regarded as a key process determining the fitness of individuals and viability of animal populations. For marine turtles that nest on beaches, this is particularly pivotal as the nesting environment can significantly control reproductive success.The aim of this study was to identify the environmental attributes of beaches (i.e., morphology, vegetation, urbanisation) that may be associated with successful oviposition in green and loggerhead turtle nests. Methods We quantified the proximity of turtle nests (and surrounding beach locations) to urban areas, measured their exposure to artificial light, and used ultra-high resolution (cm-scale) digital surface models derived from Structure-from-Motion (SfM) algorithms, to characterise geomorphic and vegetation features of beaches on the Sunshine Coast, eastern Australia. Results At small spatial scales (i.e., <100 m), we found no evidence that turtles selected nest sites based on a particular suite of environmental attributes (i.e., the attributes of nest sites were not consistently different from those of surrounding beach locations). Nest sites were, however, typically characterised by occurring close to vegetation, on parts of the shore where the beach- and dune-face was concave and not highly rugged, and in areas with moderate exposure to artificial light. Conclusion This study used a novel empirical approach to identify the attributes of turtle nest sites from a broader ‘envelope’ of environmental nest traits, and is the first step towards optimizing conservation actions to mitigate, at the local scale, present and emerging human impacts on turtle nesting beaches. PMID:28070454

  17. Selecting a proper design period for heliostat field layout optimization using Campo code

    NASA Astrophysics Data System (ADS)

    Saghafifar, Mohammad; Gadalla, Mohamed

    2016-09-01

    In this paper, different approaches are considered to calculate the cosine factor which is utilized in Campo code to expand the heliostat field layout and maximize its annual thermal output. Furthermore, three heliostat fields containing different number of mirrors are taken into consideration. Cosine factor is determined by considering instantaneous and time-average approaches. For instantaneous method, different design days and design hours are selected. For the time average method, daily time average, monthly time average, seasonally time average, and yearly time averaged cosine factor determinations are considered. Results indicate that instantaneous methods are more appropriate for small scale heliostat field optimization. Consequently, it is proposed to consider the design period as the second design variable to ensure the best outcome. For medium and large scale heliostat fields, selecting an appropriate design period is more important. Therefore, it is more reliable to select one of the recommended time average methods to optimize the field layout. Optimum annual weighted efficiency for heliostat fields (small, medium, and large) containing 350, 1460, and 3450 mirrors are 66.14%, 60.87%, and 54.04%, respectively.

  18. A multi-fidelity analysis selection method using a constrained discrete optimization formulation

    NASA Astrophysics Data System (ADS)

    Stults, Ian C.

    The purpose of this research is to develop a method for selecting the fidelity of contributing analyses in computer simulations. Model uncertainty is a significant component of result validity, yet it is neglected in most conceptual design studies. When it is considered, it is done so in only a limited fashion, and therefore brings the validity of selections made based on these results into question. Neglecting model uncertainty can potentially cause costly redesigns of concepts later in the design process or can even cause program cancellation. Rather than neglecting it, if one were to instead not only realize the model uncertainty in tools being used but also use this information to select the tools for a contributing analysis, studies could be conducted more efficiently and trust in results could be quantified. Methods for performing this are generally not rigorous or traceable, and in many cases the improvement and additional time spent performing enhanced calculations are washed out by less accurate calculations performed downstream. The intent of this research is to resolve this issue by providing a method which will minimize the amount of time spent conducting computer simulations while meeting accuracy and concept resolution requirements for results. In many conceptual design programs, only limited data is available for quantifying model uncertainty. Because of this data sparsity, traditional probabilistic means for quantifying uncertainty should be reconsidered. This research proposes to instead quantify model uncertainty using an evidence theory formulation (also referred to as Dempster-Shafer theory) in lieu of the traditional probabilistic approach. Specific weaknesses in using evidence theory for quantifying model uncertainty are identified and addressed for the purposes of the Fidelity Selection Problem. A series of experiments was conducted to address these weaknesses using n-dimensional optimization test functions. These experiments found that model

  19. Suitability of oyster restoration sites along the Louisiana coast: Examining site and stock × site interaction

    USGS Publications Warehouse

    Schwarting Miller, Lindsay; La Peyre, Jerome F.; LaPeyre, Megan K.

    2017-01-01

    Recognition of the global loss of subtidal oyster reefs has led to a rise in reef restoration efforts, including in the Gulf of Mexico. Created reef success depends entirely on selecting a location that supports long-term oyster growth and survival, including the recruitment and survival of on-reef oysters. Significant changes in estuarine salinity through management of freshwater inflows and through changed precipitation patterns may significantly impact the locations of optimal oyster restoration sites. These rapid shifts in conditions necessitate a need to better understand both impacts to on-reef oyster growth and population development, and variation in oyster stock performance. Oyster growth, mortality, condition, and disease prevalence were examined in three different stocks of oysters located in protected cages, as well as oyster recruitment and mortality on experimental reef units in three different locations representing a salinity gradient, along the Louisiana Gulf coast in 2011 and 2012. Over a 2-y period, the high-salinity site had highest oyster growth rate in protected cages but demonstrated the least likelihood for reef development based on on-reef oyster population failure, likely because of predation-related mortality (high recruitment and 100% mortality). In contrast, the midsalinity site with moderate oyster growth and on-reef recruitment and low mortality demonstrated a higher likelihood for reef development. The lowest salinity site exhibited extreme variability in all oyster responses between years because of extreme variation in environmental conditions during the study, indicating a low likelihood of long-term reef development. Whereas limited differences in stock performance between sites were found, the range of site environmental conditions tested was ultimately much lower than expected and may not have provided a wide enough range of conditions. In areas with limited, low recruitment, or rapidly changing environmental conditions

  20. 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.

  1. An improved chaotic fruit fly optimization based on a mutation strategy for simultaneous feature selection and parameter optimization for SVM and its applications.

    PubMed

    Ye, Fei; Lou, Xin Yuan; Sun, Lin Fu

    2017-01-01

    This paper proposes a new support vector machine (SVM) optimization scheme based on an improved chaotic fly optimization algorithm (FOA) with a mutation strategy to simultaneously perform parameter setting turning for the SVM and feature selection. In the improved FOA, the chaotic particle initializes the fruit fly swarm location and replaces the expression of distance for the fruit fly to find the food source. However, the proposed mutation strategy uses two distinct generative mechanisms for new food sources at the osphresis phase, allowing the algorithm procedure to search for the optimal solution in both the whole solution space and within the local solution space containing the fruit fly swarm location. In an evaluation based on a group of ten benchmark problems, the proposed algorithm's performance is compared with that of other well-known algorithms, and the results support the superiority of the proposed algorithm. Moreover, this algorithm is successfully applied in a SVM to perform both parameter setting turning for the SVM and feature selection to solve real-world classification problems. This method is called chaotic fruit fly optimization algorithm (CIFOA)-SVM and has been shown to be a more robust and effective optimization method than other well-known methods, particularly in terms of solving the medical diagnosis problem and the credit card problem.

  2. [Analysis of visible extinction spectrum of particle system and selection of optimal wavelength].

    PubMed

    Sun, Xiao-gang; Tang, Hong; Yuan, Gui-bin

    2008-09-01

    In the total light scattering particle sizing technique, the extinction spectrum of particle system contains some information about the particle size and refractive index. The visible extinction spectra of the common monomodal and biomodal R-R particle size distribution were computed, and the variation in the visible extinction spectrum with the particle size and refractive index was analyzed. The corresponding wavelengths were selected as the measurement wavelengths at which the second order differential extinction spectrum was discontinuous. Furthermore, the minimum and the maximum wavelengths in the visible region were also selected as the measurement wavelengths. The genetic algorithm was used as the inversion method under the dependent model The computer simulation and experiments illustrate that it is feasible to make an analysis of the extinction spectrum and use this selection method of the optimal wavelength in the total light scattering particle sizing. The rough contour of the particle size distribution can be determined after the analysis of visible extinction spectrum, so the search range of the particle size parameter is reduced in the optimal algorithm, and then a more accurate inversion result can be obtained using the selection method. The inversion results of monomodal and biomodal distribution are all still satisfactory when 1% stochastic noise is put in the transmission extinction measurement values.

  3. Contrast based band selection for optimized weathered oil detection in hyperspectral images

    NASA Astrophysics Data System (ADS)

    Levaux, Florian; Bostater, Charles R., Jr.; Neyt, Xavier

    2012-09-01

    Hyperspectral imagery offers unique benefits for detection of land and water features due to the information contained in reflectance signatures such as the bi-directional reflectance distribution function or BRDF. The reflectance signature directly shows the relative absorption and backscattering features of targets. These features can be very useful in shoreline monitoring or surveillance applications, for example to detect weathered oil. In real-time detection applications, processing of hyperspectral data can be an important tool and Optimal band selection is thus important in real time applications in order to select the essential bands using the absorption and backscatter information. In the present paper, band selection is based upon the optimization of target detection using contrast algorithms. The common definition of the contrast (using only one band out of all possible combinations available within a hyperspectral image) is generalized in order to consider all the possible combinations of wavelength dependent contrasts using hyperspectral images. The inflection (defined here as an approximation of the second derivative) is also used in order to enhance the variations in the reflectance spectra as well as in the contrast spectrua in order to assist in optimal band selection. The results of the selection in term of target detection (false alarms and missed detection) are also compared with a previous method to perform feature detection, namely the matched filter. In this paper, imagery is acquired using a pushbroom hyperspectral sensor mounted at the bow of a small vessel. The sensor is mechanically rotated using an optical rotation stage. This opto-mechanical scanning system produces hyperspectral images with pixel sizes on the order of mm to cm scales, depending upon the distance between the sensor and the shoreline being monitored. The motion of the platform during the acquisition induces distortions in the collected HSI imagery. It is therefore

  4. An Optimization and Assessment on DG adoption in JapanesePrototype Buildings

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

    Zhou, Nan; Marnay, Chris; Firestone, Ryan

    2005-11-30

    This research investigates a method of choosing economicallyoptimal DER, expanding on prior studies at the Berkeley Lab using the DERdesign optimization program, the Distributed Energy Resources CustomerAdoption Model (DER-CAM). DER-CAM finds the optimal combination ofinstalled equipment from available DER technologies, given prevailingutility tariffs, site electrical and thermal loads, and a menu ofavailable equipment. It provides a global optimization, albeit idealized,that shows how the site energy load scan be served at minimum cost byselection and operation of on-site generation, heat recovery, andcooling. Five prototype Japanese commercial buildings are examined andDER-CAM applied to select thee conomically optimal DER system for each.The fivemore » building types are office, hospital, hotel, retail, and sportsfacility. Based on the optimization results, energy and emissionreductions are evaluated. Furthermore, a Japan-U.S. comparison study ofpolicy, technology, and utility tariffs relevant to DER installation ispresented. Significant decreases in fuel consumption, carbon emissions,and energy costs were seen in the DER-CAM results. Savings were mostnoticeable in the sports facility, followed by the hospital, hotel, andoffice building.« less

  5. Optimal marker-assisted selection to increase the effective size of small populations.

    PubMed

    Wang, J

    2001-02-01

    An approach to the optimal utilization of marker and pedigree information in minimizing the rates of inbreeding and genetic drift at the average locus of the genome (not just the marked loci) in a small diploid population is proposed, and its efficiency is investigated by stochastic simulations. The approach is based on estimating the expected pedigree of each chromosome by using marker and individual pedigree information and minimizing the average coancestry of selected chromosomes by quadratic integer programming. It is shown that the approach is much more effective and much less computer demanding in implementation than previous ones. For pigs with 10 offspring per mother genotyped for two markers (each with four alleles at equal initial frequency) per chromosome of 100 cM, the approach can increase the average effective size for the whole genome by approximately 40 and 55% if mating ratios (the number of females mated with a male) are 3 and 12, respectively, compared with the corresponding values obtained by optimizing between-family selection using pedigree information only. The efficiency of the marker-assisted selection method increases with increasing amount of marker information (number of markers per chromosome, heterozygosity per marker) and family size, but decreases with increasing genome size. For less prolific species, the approach is still effective if the mating ratio is large so that a high marker-assisted selection pressure on the rarer sex can be maintained.

  6. Accurate in silico prediction of species-specific methylation sites based on information gain feature optimization.

    PubMed

    Wen, Ping-Ping; Shi, Shao-Ping; Xu, Hao-Dong; Wang, Li-Na; Qiu, Jian-Ding

    2016-10-15

    As one of the most important reversible types of post-translational modification, protein methylation catalyzed by methyltransferases carries many pivotal biological functions as well as many essential biological processes. Identification of methylation sites is prerequisite for decoding methylation regulatory networks in living cells and understanding their physiological roles. Experimental methods are limitations of labor-intensive and time-consuming. While in silicon approaches are cost-effective and high-throughput manner to predict potential methylation sites, but those previous predictors only have a mixed model and their prediction performances are not fully satisfactory now. Recently, with increasing availability of quantitative methylation datasets in diverse species (especially in eukaryotes), there is a growing need to develop a species-specific predictor. Here, we designed a tool named PSSMe based on information gain (IG) feature optimization method for species-specific methylation site prediction. The IG method was adopted to analyze the importance and contribution of each feature, then select the valuable dimension feature vectors to reconstitute a new orderly feature, which was applied to build the finally prediction model. Finally, our method improves prediction performance of accuracy about 15% comparing with single features. Furthermore, our species-specific model significantly improves the predictive performance compare with other general methylation prediction tools. Hence, our prediction results serve as useful resources to elucidate the mechanism of arginine or lysine methylation and facilitate hypothesis-driven experimental design and validation. The tool online service is implemented by C# language and freely available at http://bioinfo.ncu.edu.cn/PSSMe.aspx CONTACT: jdqiu@ncu.edu.cnSupplementary information: Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights

  7. Disulfide bridge regulates ligand-binding site selectivity in liver bile acid-binding proteins.

    PubMed

    Cogliati, Clelia; Tomaselli, Simona; Assfalg, Michael; Pedò, Massimo; Ferranti, Pasquale; Zetta, Lucia; Molinari, Henriette; Ragona, Laura

    2009-10-01

    Bile acid-binding proteins (BABPs) are cytosolic lipid chaperones that play central roles in driving bile flow, as well as in the adaptation to various pathological conditions, contributing to the maintenance of bile acid homeostasis and functional distribution within the cell. Understanding the mode of binding of bile acids with their cytoplasmic transporters is a key issue in providing a model for the mechanism of their transfer from the cytoplasm to the nucleus, for delivery to nuclear receptors. A number of factors have been shown to modulate bile salt selectivity, stoichiometry, and affinity of binding to BABPs, e.g. chemistry of the ligand, protein plasticity and, possibly, the formation of disulfide bridges. Here, the effects of the presence of a naturally occurring disulfide bridge on liver BABP ligand-binding properties and backbone dynamics have been investigated by NMR. Interestingly, the disulfide bridge does not modify the protein-binding stoichiometry, but has a key role in modulating recognition at both sites, inducing site selectivity for glycocholic and glycochenodeoxycholic acid. Protein conformational changes following the introduction of a disulfide bridge are small and located around the inner binding site, whereas significant changes in backbone motions are observed for several residues distributed over the entire protein, both in the apo form and in the holo form. Site selectivity appears, therefore, to be dependent on protein mobility rather than being governed by steric factors. The detected properties further establish a parallelism with the behaviour of human ileal BABP, substantiating the proposal that BABPs have parallel functions in hepatocytes and enterocytes.

  8. Evaluating Varied Label Designs for Use with Medical Devices: Optimized Labels Outperform Existing Labels in the Correct Selection of Devices and Time to Select.

    PubMed

    Bix, Laura; Seo, Do Chan; Ladoni, Moslem; Brunk, Eric; Becker, Mark W

    2016-01-01

    Effective standardization of medical device labels requires objective study of varied designs. Insufficient empirical evidence exists regarding how practitioners utilize and view labeling. Measure the effect of graphic elements (boxing information, grouping information, symbol use and color-coding) to optimize a label for comparison with those typical of commercial medical devices. Participants viewed 54 trials on a computer screen. Trials were comprised of two labels that were identical with regard to graphics, but differed in one aspect of information (e.g., one had latex, the other did not). Participants were instructed to select the label along a given criteria (e.g., latex containing) as quickly as possible. Dependent variables were binary (correct selection) and continuous (time to correct selection). Eighty-nine healthcare professionals were recruited at Association of Surgical Technologists (AST) conferences, and using a targeted e-mail of AST members. Symbol presence, color coding and grouping critical pieces of information all significantly improved selection rates and sped time to correct selection (α = 0.05). Conversely, when critical information was graphically boxed, probability of correct selection and time to selection were impaired (α = 0.05). Subsequently, responses from trials containing optimal treatments (color coded, critical information grouped with symbols) were compared to two labels created based on a review of those commercially available. Optimal labels yielded a significant positive benefit regarding the probability of correct choice ((P<0.0001) LSM; UCL, LCL: 97.3%; 98.4%, 95.5%)), as compared to the two labels we created based on commercial designs (92.0%; 94.7%, 87.9% and 89.8%; 93.0%, 85.3%) and time to selection. Our study provides data regarding design factors, namely: color coding, symbol use and grouping of critical information that can be used to significantly enhance the performance of medical device labels.

  9. Nucleic acid constructs containing orthogonal site selective recombinases (OSSRs)

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

    Gilmore, Joshua M.; Anderson, J. Christopher; Dueber, John E.

    The present invention provides for a recombinant nucleic acid comprising a nucleotide sequence comprising a plurality of constructs, wherein each construct independently comprises a nucleotide sequence of interest flanked by a pair of recombinase recognition sequences. Each pair of recombinase recognition sequences is recognized by a distinct recombinase. Optionally, each construct can, independently, further comprise one or more genes encoding a recombinase capable of recognizing the pair of recombinase recognition sequences of the construct. The recombinase can be an orthogonal (non-cross reacting), site-selective recombinase (OSSR).

  10. Use of technical and economic analysis for optimizing technology selection and remedial design for contaminated sites

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

    Hardisty, P.E.; Brown, A.

    1996-12-01

    The decision to remediate a contaminated site can be seen from the macroeconomic and microeconomic viewpoints. Macroeconomics can be used to plan and account for the overall cost of pollution as part of a firm`s production, and thus make overall decisions on the real cost of pollution and the level of clean-up which may be called for. Valuation of damaged resources, option values and intrinsic worth is an important part of this process. Once the decision to remediate has been taken, the question becomes how best to remediate. Microeconomic analysis deals with providing efficient allocative decisions for reaching specified goals.more » it is safe to say that cost is one of the single most important factors in site clean-up decision making. A basic rule of remediation is often taken to be the maximization of contaminant mass removed per dollar spent. However, remediation may also be governed by other objectives and constraints. In some situations, minimization of time, rather than cost, could be the constraint. Or perhaps the objective could be to achieve a set level of clean-up for the lowest possible cost, even if a large program would result in unit-cost reductions. Evaluation of the economics of a clean-up project is directly linked to the objectives of the site owner, and the constraints within which the remediation is to be performed. Economic analysis of remedial options for containment of a 350,000 L hydrocarbon spill migrating through fractured rock into a river in Alberta, Canada, clear direction to the site owner.« less

  11. 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.

  12. Site-selective benzoin-type cyclization of unsymmetrical dialdoses catalyzed by N-heterocyclic carbenes for divergent cyclitol synthesis.

    PubMed

    Kang, Bubwoong; Wang, Yinli; Kuwano, Satoru; Yamaoka, Yousuke; Takasu, Kiyosei; Yamada, Ken-Ichi

    2017-04-18

    A highly site-selective N-heterocyclic carbene (NHC)-catalyzed benzoin-type cyclization of unsymmetrical dialdoses is developed to enable a divergent cyclitol synthesis. The choice of chiral NHCs and protecting groups affects the site-selectivity. The resulting inososes are converted into epi-, muco- and myo-inositols, and their chiral protected derivatives are formed in good yields.

  13. Electrical latency predicts the optimal left ventricular endocardial pacing site: results from a multicentre international registry.

    PubMed

    Sieniewicz, Benjamin J; Behar, Jonathan M; Sohal, Manav; Gould, Justin; Claridge, Simon; Porter, Bradley; Niederer, Steve; Gamble, James H P; Betts, Tim R; Jais, Pierre; Derval, Nicolas; Spragg, David D; Steendijk, Paul; van Gelder, Berry M; Bracke, Frank A; Rinaldi, Christopher A

    2018-04-23

    The optimal site for biventricular endocardial (BIVENDO) pacing remains undefined. Acute haemodynamic response (AHR) is reproducible marker of left ventricular (LV) contractility, best expressed as the change in the maximum rate of LV pressure (LV-dp/dtmax), from a baseline state. We examined the relationship between factors known to impact LV contractility, whilst delivering BIVENDO pacing at a variety of LV endocardial (LVENDO) locations. We compiled a registry of acute LVENDO pacing studies from five international centres: Johns Hopkins-USA, Bordeaux-France, Eindhoven-The Netherlands, Oxford-United Kingdom, and Guys and St Thomas' NHS Foundation Trust, London-UK. In all, 104 patients incorporating 687 endocardial and 93 epicardial pacing locations were studied. Mean age was 66 ± 11 years, mean left ventricular ejection fraction 24.6 ± 7.7% and mean QRS duration of 163 ± 30 ms. In all, 50% were ischaemic [ischaemic cardiomyopathy (ICM)]. Scarred segments were associated with worse haemodynamics (dp/dtmax; 890 mmHg/s vs. 982 mmHg/s, P < 0.01). Delivering BiVENDO pacing in areas of electrical latency was associated with greater improvements in AHR (P < 0.01). Stimulating late activating tissue (LVLED >50%) achieved greater increases in AHR than non-late activating tissue (LVLED < 50%) (8.6 ± 9.6% vs. 16.1 ± 16.2%, P = 0.002). However, the LVENDO pacing location with the latest Q-LV, was associated with the optimal AHR in just 62% of cases. Identifying viable LVENDO tissue which displays late electrical activation is crucial to identifying the optimal BiVENDO pacing site. Stimulating late activating tissue (LVLED >50%) yields greater improvements in AHR however, the optimal location is frequently not the site of latest activation.

  14. 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.

  15. Long-term function and optimization of mouse and human islet transplantation in the subcutaneous device-less site

    PubMed Central

    Pepper, Andrew R.; Pawlick, Rena L.; Gala-Lopez, Boris

    2016-01-01

    ABSTRACT Clinical islet transplantation has routinely been demonstrated to be an efficacious means of restoring glycemic control in select patients with autoimmune diabetes. Notwithstanding marked progress and improvements, the broad-spectrum application of this treatment option is restricted by the complications associated with intrahepatic portal cellular infusion and the scarcity of human donor pancreata. Recent progress in stem cell biology has demonstrated that the potential to expand new β cells for clinical transplantation is now a reality. As such, research focus is being directed toward optimizing safe extrahepatic transplant sites to house future alternative β cell sources for clinical use. The present study expands on our previous development of a prevascularized subcutaneous device-less (DL) technique for cellular transplantation, by demonstrating long-term (>365 d) durable syngeneic murine islet graft function. Furthermore, histological analysis of tissue specimens collected immediately post-DL site creation and acutely post-human islet transplantation demonstrates that this technique results in close apposition of the neovascularized collagen to the transplanted cells without dead space, thereby avoiding hypoxic luminal dead-space. Murine islets transplanted into the DL site created by a larger luminal diameter (6-Fr.) (n = 11), reversed diabetes to the similar capacity as our standard DL method (5-Fr.)(n = 9). Furthermore, glucose tolerance testing did not differ between these 2 transplant groups (p > 0 .05). Taken together, this further refinement of the DL transplant approach facilitates a simplistic means of islet infusion, increases the transplant volume capacity and may provide an effective microenvironment to house future alternative β cell sources. PMID:27820660

  16. Long-term function and optimization of mouse and human islet transplantation in the subcutaneous device-less site.

    PubMed

    Pepper, Andrew R; Bruni, Antonio; Pawlick, Rena L; Gala-Lopez, Boris; Rafiei, Yasmin; Wink, John; Kin, Tatsuya; Shapiro, A M James

    2016-11-01

    Clinical islet transplantation has routinely been demonstrated to be an efficacious means of restoring glycemic control in select patients with autoimmune diabetes. Notwithstanding marked progress and improvements, the broad-spectrum application of this treatment option is restricted by the complications associated with intrahepatic portal cellular infusion and the scarcity of human donor pancreata. Recent progress in stem cell biology has demonstrated that the potential to expand new β cells for clinical transplantation is now a reality. As such, research focus is being directed toward optimizing safe extrahepatic transplant sites to house future alternative β cell sources for clinical use. The present study expands on our previous development of a prevascularized subcutaneous device-less (DL) technique for cellular transplantation, by demonstrating long-term (>365 d) durable syngeneic murine islet graft function. Furthermore, histological analysis of tissue specimens collected immediately post-DL site creation and acutely post-human islet transplantation demonstrates that this technique results in close apposition of the neovascularized collagen to the transplanted cells without dead space, thereby avoiding hypoxic luminal dead-space. Murine islets transplanted into the DL site created by a larger luminal diameter (6-Fr.) (n = 11), reversed diabetes to the similar capacity as our standard DL method (5-Fr.)(n = 9). Furthermore, glucose tolerance testing did not differ between these 2 transplant groups (p > 0 .05). Taken together, this further refinement of the DL transplant approach facilitates a simplistic means of islet infusion, increases the transplant volume capacity and may provide an effective microenvironment to house future alternative β cell sources.

  17. Methodology and Estimates of Scour at Selected Bridge Sites in Alaska

    USGS Publications Warehouse

    Heinrichs, Thomas A.; Kennedy, Ben W.; Langley, Dustin E.; Burrows, Robert L.

    2001-01-01

    The U.S. Geological Survey estimated scour depths at 325 bridges in Alaska as part of a cooperative agreement with the Alaska Department of Transportation and Public Facilities. The department selected these sites from approximately 806 State-owned bridges as potentially susceptible to scour during extreme floods. Pier scour and contraction scour were computed for the selected bridges by using methods recommended by the Federal Highway Administration. The U.S. Geological Survey used a four-step procedure to estimate scour: (1) Compute magnitudes of the 100- and 500-year floods. (2) Determine cross-section geometry and hydraulic properties for each bridge site. (3) Compute the water-surface profile for the 100- and 500-year floods. (4) Compute contraction and pier scour. This procedure is unique because the cross sections were developed from existing data on file to make a quantitative estimate of scour. This screening method has the advantage of providing scour depths and bed elevations for comparison with bridge-foundation elevations without the time and expense of a field survey. Four examples of bridge-scour analyses are summarized in the appendix.

  18. An enhancement of binary particle swarm optimization for gene selection in classifying cancer classes

    PubMed Central

    2013-01-01

    Background Gene expression data could likely be a momentous help in the progress of proficient cancer diagnoses and classification platforms. Lately, many researchers analyze gene expression data using diverse computational intelligence methods, for selecting a small subset of informative genes from the data for cancer classification. Many computational methods face difficulties in selecting small subsets due to the small number of samples compared to the huge number of genes (high-dimension), irrelevant genes, and noisy genes. Methods We propose an enhanced binary particle swarm optimization to perform the selection of small subsets of informative genes which is significant for cancer classification. Particle speed, rule, and modified sigmoid function are introduced in this proposed method to increase the probability of the bits in a particle’s position to be zero. The method was empirically applied to a suite of ten well-known benchmark gene expression data sets. Results The performance of the proposed method proved to be superior to other previous related works, including the conventional version of binary particle swarm optimization (BPSO) in terms of classification accuracy and the number of selected genes. The proposed method also requires lower computational time compared to BPSO. PMID:23617960

  19. Incorporating in situ habitat patchiness in site selection models reveals that site fidelity is not always a consequence of animal choice.

    PubMed

    Martinez, Aline S; Queiroz, Eduardo V; Bryson, Mitch; Byrne, Maria; Coleman, Ross A

    2017-07-01

    Understanding site fidelity is important in animal ecology, but evidence is lacking that this behaviour is due to an animal choosing a specific location. To discern site selection behaviour, it is necessary to consider the spatial distribution of habitats that animals can occupy within a landscape. Tracking animals and defining clear habitat boundaries, however, is often difficult. We use in situ habitat distribution data and animal movement simulations to investigate behavioural choice in site fidelity patterns. We resolved the difficulty of gathering data by working with intertidal rock pool systems, which are of manageable size and where boundaries are easy to define. Movements of the intertidal starfish Parvulastra exigua were quantified to test the hypotheses that (1) this species displays fidelity to a particular rock pool and that (2) rock pool fidelity is due to site selection behaviour. Observed patterns of individuals (n = 10 starfish) returning to a previously occupied rock pool (n = 5 pools per location) were tested against an expected null distribution generated through simulations of random movements within their natural patchy environment. Starfish exhibited site selection behaviour at only one location even though site fidelity was high (av. 7·4 starfish out of 10 found in test pools) in two of the three locations. The random chance of a starfish returning to a pool increased 67% for each metre further a rock pool was from the original pool, and 120% for each square metre increase in surface area of an original pool. The decision of returning to an original rock pool was influenced by food availability. When microalgal cover was >60%, there was a c. 50% chance of animals staying faithful to that pool. Our results show the importance to consider spatial distribution of habitats in understanding patterns of animal movement associated with animal choices and site fidelity. Returning to a particular place does not necessarily mean that an animal

  20. Genetic selection for a highly functional cysteine-less membrane protein using site-saturation mutagenesis

    PubMed Central

    Arendt, Cassandra S.; Ri, Keirei; Yates, Phillip A.; Ullman, Buddy

    2007-01-01

    We describe an efficient method for generating highly functional membrane proteins with variant amino acids at defined positions that couples a modified site-saturation strategy with functional genetic selection. We applied this method to the production of a cysteine-less variant of the Crithidia fasciculata inosine-guanosine permease CfNT2, in order to facilitate biochemical studies using thiol-specific modifying reagents. Of ten endogenous cysteine residues in CfNT2, two cannot be replaced with serine or alanine without loss of function. High-quality single- and double-mutant libraries were produced by combining a previously reported site-saturation mutagenesis scheme based on the Quikchange method with a novel gel purification step that effectively eliminated template DNA from the products. Following selection for functional complementation in S. cerevisiae cells auxotrophic for purines, several highly functional non-cysteine substitutions were efficiently identified at each desired position, allowing the construction of cysteine-less variants of CfNT2 that retained wild-type affinity for inosine. This combination of an improved site-saturation mutagenesis technique and positive genetic selection provides a simple and efficient means to identify functional and perhaps unexpected amino acid variants at a desired position. PMID:17481563

  1. 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

  2. A Miniaturized Spectrometer for Optimized Selection of Subsurface Samples for Future MSR Missions

    NASA Astrophysics Data System (ADS)

    De Sanctis, M. C.; Altieri, F.; De Angelis, S.; Ferrari, M.; Frigeri, A.; Biondi, D.; Novi, S.; Antonacci, F.; Gabrieli, R.; Paolinetti, R.; Villa, F.; Ammannito, A.; Mugnuolo, R.; Pirrotta, S.

    2018-04-01

    We present the concept of a miniaturized spectrometer based on the ExoMars2020/Ma_MISS experiment. Coupled with a drill tool, it will allow an assessment of subsurface composition and optimize the selection of martian samples with a high astrobiological potential.

  3. Age-related differences in goals: testing predictions from selection, optimization, and compensation theory and socioemotional selectivity theory.

    PubMed

    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 theories. Older adults and two groups of younger adults (college students and non-students) listed their current goals, which were then coded by independent raters. Observed age group differences in goals generally supported both theories. Specifically, when compared to younger adults, older adults reported more goals focused on maintenance/loss prevention, the present, emotion-focus and generativity, and social selection, and less goals focused on knowledge acquisition and the future. However, contrary to prediction, older adults also showed less goal focusing than younger adults, reporting goals from a broader set of life domains (e.g., health, property/possessions, friendship).

  4. Visibility Analysis of Domestic Satellites on Proposed Ground Sites for Optical Surveillance

    NASA Astrophysics Data System (ADS)

    Kim, Jae-Hyuk; Jo, Jung Hyun; Choi, Jin; Moon, Hong-Kyu; Choi, Young-Jun; Yim, Hong-Suh; Park, Jang-Hyun; Park, Eun-Seo; Park, Jong-Uk

    2011-12-01

    The objectives of this study are to analyze the satellite visibility at the randomly established ground sites, to determine the five optimal ground sites to perform the optical surveillance and tracking of domestic satellites, and to verify the acquisition of the optical observation time sufficient to maintain the precise ephemeris at optimal ground sites that have been already determined. In order to accomplish these objectives, we analyzed the visibility for sun-synchronous orbit satellites, low earth orbit satellites, middle earth orbit satellites and domestic satellites as well as the continuous visibility along with the fictitious satellite ground track, and calculate the effective visibility. For the analysis, we carried out a series of repetitive process using the satellite tool kit simulation software developed by Analytical Graphics Incorporated. The lighting states of the penumbra and direct sun were set as the key constraints of the optical observation. The minimum of the observation satellite elevation angle was set to be 20 degree, whereas the maximum of the sun elevation angle was set to be -10 degree which is within the range of the nautical twilight. To select the candidates for the optimal optical observation, the entire globe was divided into 84 sectors in a constant interval, the visibility characteristics of the individual sectors were analyzed, and 17 ground sites were arbitrarily selected and analyzed further. Finally, five optimal ground sites (Khurel Togoot Observatory, Assy-Turgen Observatory, Tubitak National Observatory, Bisdee Tier Optical Astronomy Observatory, and South Africa Astronomical Observatory) were determined. The total observation period was decided as one year. To examine the seasonal variation, the simulation was performed for the period of three days or less with respect to spring, summer, fall and winter. In conclusion, we decided the optimal ground sites to perform the optical surveillance and tracking of domestic

  5. Application of an Optimal Tuner Selection Approach for On-Board Self-Tuning Engine Models

    NASA Technical Reports Server (NTRS)

    Simon, Donald L.; Armstrong, Jeffrey B.; Garg, Sanjay

    2012-01-01

    An enhanced design methodology for minimizing the error in on-line Kalman filter-based aircraft engine performance estimation applications is presented in this paper. It specific-ally addresses the under-determined estimation problem, in which there are more unknown parameters than available sensor measurements. This work builds upon an existing technique for systematically selecting 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. While the existing technique was optimized for open-loop engine operation at a fixed design point, in this paper an alternative formulation is presented that enables the technique to be optimized for an engine operating under closed-loop control throughout the flight envelope. The theoretical Kalman filter mean squared estimation error at a steady-state closed-loop operating point is derived, and the tuner selection approach applied to minimize this error is discussed. A technique for constructing a globally optimal tuning parameter vector, which enables full-envelope application of the technology, is also presented, along with design steps for adjusting the dynamic response of the Kalman filter state estimates. Results from the application of the technique to linear and nonlinear aircraft engine simulations are presented and compared to the conventional approach of tuner selection. The new methodology is shown to yield a significant improvement in on-line Kalman filter estimation accuracy.

  6. Site Selection and Resource Allocation of Oil Spill Emergency Base for Offshore Oil Facilities

    NASA Astrophysics Data System (ADS)

    Li, Yunbin; Liu, Jingxian; Wei, Lei; Wu, Weihuang

    2018-02-01

    Based on the analysis of the historical data about oil spill accidents in the Bohai Sea, this paper discretizes oil spilled source into a limited number of spill points. According to the probability of oil spill risk, the demand for salvage forces at each oil spill point is evaluated. Aiming at the specific location of the rescue base around the Bohai Sea, a cost-benefit analysis is conducted to determine the total cost of disasters for each rescue base. Based on the relationship between the oil spill point and the rescue site, a multi-objective optimization location model for the oil spill rescue base in the Bohai Sea region is established. And the genetic algorithm is used to solve the optimization problem, and determine the emergency rescue base optimization program and emergency resources allocation ratio.

  7. An improved chaotic fruit fly optimization based on a mutation strategy for simultaneous feature selection and parameter optimization for SVM and its applications

    PubMed Central

    Lou, Xin Yuan; Sun, Lin Fu

    2017-01-01

    This paper proposes a new support vector machine (SVM) optimization scheme based on an improved chaotic fly optimization algorithm (FOA) with a mutation strategy to simultaneously perform parameter setting turning for the SVM and feature selection. In the improved FOA, the chaotic particle initializes the fruit fly swarm location and replaces the expression of distance for the fruit fly to find the food source. However, the proposed mutation strategy uses two distinct generative mechanisms for new food sources at the osphresis phase, allowing the algorithm procedure to search for the optimal solution in both the whole solution space and within the local solution space containing the fruit fly swarm location. In an evaluation based on a group of ten benchmark problems, the proposed algorithm’s performance is compared with that of other well-known algorithms, and the results support the superiority of the proposed algorithm. Moreover, this algorithm is successfully applied in a SVM to perform both parameter setting turning for the SVM and feature selection to solve real-world classification problems. This method is called chaotic fruit fly optimization algorithm (CIFOA)-SVM and has been shown to be a more robust and effective optimization method than other well-known methods, particularly in terms of solving the medical diagnosis problem and the credit card problem. PMID:28369096

  8. A feasibility study: Selection of a personalized radiotherapy fractionation schedule using spatiotemporal optimization

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

    Kim, Minsun, E-mail: mk688@uw.edu; Stewart, Robert D.; Phillips, Mark H.

    2015-11-15

    Purpose: To investigate the impact of using spatiotemporal optimization, i.e., intensity-modulated spatial optimization followed by fractionation schedule optimization, to select the patient-specific fractionation schedule that maximizes the tumor biologically equivalent dose (BED) under dose constraints for multiple organs-at-risk (OARs). Methods: Spatiotemporal optimization was applied to a variety of lung tumors in a phantom geometry using a range of tumor sizes and locations. The optimal fractionation schedule for a patient using the linear-quadratic cell survival model depends on the tumor and OAR sensitivity to fraction size (α/β), the effective tumor doubling time (T{sub d}), and the size and location of tumormore » target relative to one or more OARs (dose distribution). The authors used a spatiotemporal optimization method to identify the optimal number of fractions N that maximizes the 3D tumor BED distribution for 16 lung phantom cases. The selection of the optimal fractionation schedule used equivalent (30-fraction) OAR constraints for the heart (D{sub mean} ≤ 45 Gy), lungs (D{sub mean} ≤ 20 Gy), cord (D{sub max} ≤ 45 Gy), esophagus (D{sub max} ≤ 63 Gy), and unspecified tissues (D{sub 05} ≤ 60 Gy). To assess plan quality, the authors compared the minimum, mean, maximum, and D{sub 95} of tumor BED, as well as the equivalent uniform dose (EUD) for optimized plans to conventional intensity-modulated radiation therapy plans prescribing 60 Gy in 30 fractions. A sensitivity analysis was performed to assess the effects of T{sub d} (3–100 days), tumor lag-time (T{sub k} = 0–10 days), and the size of tumors on optimal fractionation schedule. Results: Using an α/β ratio of 10 Gy, the average values of tumor max, min, mean BED, and D{sub 95} were up to 19%, 21%, 20%, and 19% larger than those from conventional prescription, depending on T{sub d} and T{sub k} used. Tumor EUD was up to 17% larger than the conventional prescription. For fast

  9. Tabu search and binary particle swarm optimization for feature selection using microarray data.

    PubMed

    Chuang, Li-Yeh; Yang, Cheng-Huei; Yang, Cheng-Hong

    2009-12-01

    Gene expression profiles have great potential as a medical diagnosis tool because they represent the state of a cell at the molecular level. In the classification of cancer type research, available training datasets generally have a fairly small sample size compared to the number of genes involved. This fact poses an unprecedented challenge to some classification methodologies due to training data limitations. Therefore, a good selection method for genes relevant for sample classification is needed to improve the predictive accuracy, and to avoid incomprehensibility due to the large number of genes investigated. In this article, we propose to combine tabu search (TS) and binary particle swarm optimization (BPSO) for feature selection. BPSO acts as a local optimizer each time the TS has been run for a single generation. The K-nearest neighbor method with leave-one-out cross-validation and support vector machine with one-versus-rest serve as evaluators of the TS and BPSO. The proposed method is applied and compared to the 11 classification problems taken from the literature. Experimental results show that our method simplifies features effectively and either obtains higher classification accuracy or uses fewer features compared to other feature selection methods.

  10. Efficient Iris Recognition Based on Optimal Subfeature Selection and Weighted Subregion Fusion

    PubMed Central

    Deng, Ning

    2014-01-01

    In this paper, we propose three discriminative feature selection strategies and weighted subregion matching method to improve the performance of iris recognition system. Firstly, we introduce the process of feature extraction and representation based on scale invariant feature transformation (SIFT) in detail. Secondly, three strategies are described, which are orientation probability distribution function (OPDF) based strategy to delete some redundant feature keypoints, magnitude probability distribution function (MPDF) based strategy to reduce dimensionality of feature element, and compounded strategy combined OPDF and MPDF to further select optimal subfeature. Thirdly, to make matching more effective, this paper proposes a novel matching method based on weighted sub-region matching fusion. Particle swarm optimization is utilized to accelerate achieve different sub-region's weights and then weighted different subregions' matching scores to generate the final decision. The experimental results, on three public and renowned iris databases (CASIA-V3 Interval, Lamp, andMMU-V1), demonstrate that our proposed methods outperform some of the existing methods in terms of correct recognition rate, equal error rate, and computation complexity. PMID:24683317

  11. Optimality and stability of symmetric evolutionary games with applications in genetic selection.

    PubMed

    Huang, Yuanyuan; Hao, Yiping; Wang, Min; Zhou, Wen; Wu, Zhijun

    2015-06-01

    Symmetric evolutionary games, i.e., evolutionary games with symmetric fitness matrices, have important applications in population genetics, where they can be used to model for example the selection and evolution of the genotypes of a given population. In this paper, we review the theory for obtaining optimal and stable strategies for symmetric evolutionary games, and provide some new proofs and computational methods. In particular, we review the relationship between the symmetric evolutionary game and the generalized knapsack problem, and discuss the first and second order necessary and sufficient conditions that can be derived from this relationship for testing the optimality and stability of the strategies. Some of the conditions are given in different forms from those in previous work and can be verified more efficiently. We also derive more efficient computational methods for the evaluation of the conditions than conventional approaches. We demonstrate how these conditions can be applied to justifying the strategies and their stabilities for a special class of genetic selection games including some in the study of genetic disorders.

  12. Efficient iris recognition based on optimal subfeature selection and weighted subregion fusion.

    PubMed

    Chen, Ying; Liu, Yuanning; Zhu, Xiaodong; He, Fei; Wang, Hongye; Deng, Ning

    2014-01-01

    In this paper, we propose three discriminative feature selection strategies and weighted subregion matching method to improve the performance of iris recognition system. Firstly, we introduce the process of feature extraction and representation based on scale invariant feature transformation (SIFT) in detail. Secondly, three strategies are described, which are orientation probability distribution function (OPDF) based strategy to delete some redundant feature keypoints, magnitude probability distribution function (MPDF) based strategy to reduce dimensionality of feature element, and compounded strategy combined OPDF and MPDF to further select optimal subfeature. Thirdly, to make matching more effective, this paper proposes a novel matching method based on weighted sub-region matching fusion. Particle swarm optimization is utilized to accelerate achieve different sub-region's weights and then weighted different subregions' matching scores to generate the final decision. The experimental results, on three public and renowned iris databases (CASIA-V3 Interval, Lamp, and MMU-V1), demonstrate that our proposed methods outperform some of the existing methods in terms of correct recognition rate, equal error rate, and computation complexity.

  13. Optimal Electrode Selection for Electrical Resistance Tomography in Carbon Fiber Reinforced Polymer Composites.

    PubMed

    Escalona Galvis, Luis Waldo; Diaz-Montiel, Paulina; Venkataraman, Satchi

    2017-02-04

    Electrical Resistance Tomography (ERT) offers a non-destructive evaluation (NDE) technique that takes advantage of the inherent electrical properties in carbon fiber reinforced polymer (CFRP) composites for internal damage characterization. This paper investigates a method of optimum selection of sensing configurations for delamination detection in thick cross-ply laminates using ERT. Reduction in the number of sensing locations and measurements is necessary to minimize hardware and computational effort. The present work explores the use of an effective independence (EI) measure originally proposed for sensor location optimization in experimental vibration modal analysis. The EI measure is used for selecting the minimum set of resistance measurements among all possible combinations resulting from selecting sensing electrode pairs. Singular Value Decomposition (SVD) is applied to obtain a spectral representation of the resistance measurements in the laminate for subsequent EI based reduction to take place. The electrical potential field in a CFRP laminate is calculated using finite element analysis (FEA) applied on models for two different laminate layouts considering a set of specified delamination sizes and locations with two different sensing arrangements. The effectiveness of the EI measure in eliminating redundant electrode pairs is demonstrated by performing inverse identification of damage using the full set and the reduced set of resistance measurements. This investigation shows that the EI measure is effective for optimally selecting the electrode pairs needed for resistance measurements in ERT based damage detection.

  14. TH-EF-BRB-05: 4pi Non-Coplanar IMRT Beam Angle Selection by Convex Optimization with Group Sparsity Penalty

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

    O’Connor, D; Nguyen, D; Voronenko, Y

    Purpose: Integrated beam orientation and fluence map optimization is expected to be the foundation of robust automated planning but existing heuristic methods do not promise global optimality. We aim to develop a new method for beam angle selection in 4π non-coplanar IMRT systems based on solving (globally) a single convex optimization problem, and to demonstrate the effectiveness of the method by comparison with a state of the art column generation method for 4π beam angle selection. Methods: The beam angle selection problem is formulated as a large scale convex fluence map optimization problem with an additional group sparsity term thatmore » encourages most candidate beams to be inactive. The optimization problem is solved using an accelerated first-order method, the Fast Iterative Shrinkage-Thresholding Algorithm (FISTA). The beam angle selection and fluence map optimization algorithm is used to create non-coplanar 4π treatment plans for several cases (including head and neck, lung, and prostate cases) and the resulting treatment plans are compared with 4π treatment plans created using the column generation algorithm. Results: In our experiments the treatment plans created using the group sparsity method meet or exceed the dosimetric quality of plans created using the column generation algorithm, which was shown superior to clinical plans. Moreover, the group sparsity approach converges in about 3 minutes in these cases, as compared with runtimes of a few hours for the column generation method. Conclusion: This work demonstrates the first non-greedy approach to non-coplanar beam angle selection, based on convex optimization, for 4π IMRT systems. The method given here improves both treatment plan quality and runtime as compared with a state of the art column generation algorithm. When the group sparsity term is set to zero, we obtain an excellent method for fluence map optimization, useful when beam angles have already been selected. NIH R43CA183390, NIH

  15. TreePOD: Sensitivity-Aware Selection of Pareto-Optimal Decision Trees.

    PubMed

    Muhlbacher, Thomas; Linhardt, Lorenz; Moller, Torsten; Piringer, Harald

    2018-01-01

    Balancing accuracy gains with other objectives such as interpretability is a key challenge when building decision trees. However, this process is difficult to automate because it involves know-how about the domain as well as the purpose of the model. This paper presents TreePOD, a new approach for sensitivity-aware model selection along trade-offs. TreePOD is based on exploring a large set of candidate trees generated by sampling the parameters of tree construction algorithms. Based on this set, visualizations of quantitative and qualitative tree aspects provide a comprehensive overview of possible tree characteristics. Along trade-offs between two objectives, TreePOD provides efficient selection guidance by focusing on Pareto-optimal tree candidates. TreePOD also conveys the sensitivities of tree characteristics on variations of selected parameters by extending the tree generation process with a full-factorial sampling. We demonstrate how TreePOD supports a variety of tasks involved in decision tree selection and describe its integration in a holistic workflow for building and selecting decision trees. For evaluation, we illustrate a case study for predicting critical power grid states, and we report qualitative feedback from domain experts in the energy sector. This feedback suggests that TreePOD enables users with and without statistical background a confident and efficient identification of suitable decision trees.

  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. Imaging multicellular specimens with real-time optimized tiling light-sheet selective plane illumination microscopy

    PubMed Central

    Fu, Qinyi; Martin, Benjamin L.; Matus, David Q.; Gao, Liang

    2016-01-01

    Despite the progress made in selective plane illumination microscopy, high-resolution 3D live imaging of multicellular specimens remains challenging. Tiling light-sheet selective plane illumination microscopy (TLS-SPIM) with real-time light-sheet optimization was developed to respond to the challenge. It improves the 3D imaging ability of SPIM in resolving complex structures and optimizes SPIM live imaging performance by using a real-time adjustable tiling light sheet and creating a flexible compromise between spatial and temporal resolution. We demonstrate the 3D live imaging ability of TLS-SPIM by imaging cellular and subcellular behaviours in live C. elegans and zebrafish embryos, and show how TLS-SPIM can facilitate cell biology research in multicellular specimens by studying left-right symmetry breaking behaviour of C. elegans embryos. PMID:27004937

  18. 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.

  19. An Optimal Centralized Carbon Dioxide Repository for Florida, USA

    PubMed Central

    Poiencot, Brandon; Brown, Christopher

    2011-01-01

    For over a decade, the United States Department of Energy, and engineers, geologists, and scientists from all over the world have investigated the potential for reducing atmospheric carbon emissions through carbon sequestration. Numerous reports exist analyzing the potential for sequestering carbon dioxide at various sites around the globe, but none have identified the potential for a statewide system in Florida, USA. In 2005, 83% of Florida’s electrical energy was produced by natural gas, coal, or oil (e.g., fossil fuels), from power plants spread across the state. In addition, only limited research has been completed on evaluating optimal pipeline transportation networks to centralized carbon dioxide repositories. This paper describes the feasibility and preliminary locations for an optimal centralized Florida-wide carbon sequestration repository. Linear programming optimization modeling is used to plan and route an idealized pipeline network to existing Florida power plants. Further analysis of the subsurface geology in these general locations will provide insight into the suitability of the subsurface conditions and the available capacity for carbon sequestration at selected possible repository sites. The identification of the most favorable site(s) is also presented. PMID:21695024

  20. An optimal centralized carbon dioxide repository for Florida, USA.

    PubMed

    Poiencot, Brandon; Brown, Christopher

    2011-04-01

    For over a decade, the United States Department of Energy, and engineers, geologists, and scientists from all over the world have investigated the potential for reducing atmospheric carbon emissions through carbon sequestration. Numerous reports exist analyzing the potential for sequestering carbon dioxide at various sites around the globe, but none have identified the potential for a statewide system in Florida, USA. In 2005, 83% of Florida's electrical energy was produced by natural gas, coal, or oil (e.g., fossil fuels), from power plants spread across the state. In addition, only limited research has been completed on evaluating optimal pipeline transportation networks to centralized carbon dioxide repositories. This paper describes the feasibility and preliminary locations for an optimal centralized Florida-wide carbon sequestration repository. Linear programming optimization modeling is used to plan and route an idealized pipeline network to existing Florida power plants. Further analysis of the subsurface geology in these general locations will provide insight into the suitability of the subsurface conditions and the available capacity for carbon sequestration at selected possible repository sites. The identification of the most favorable site(s) is also presented.

  1. Getting to the top of Google: search engine optimization.

    PubMed

    Maley, Catherine; Baum, Neil

    2010-01-01

    Search engine optimization is the process of making your Web site appear at or near the top of popular search engines such as Google, Yahoo, and MSN. This is not done by luck or knowing someone working for the search engines but by understanding the process of how search engines select Web sites for placement on top or on the first page. This article will review the process and provide methods and techniques to use to have your site rated at the top or very near the top.

  2. Exclusive Ni-N4 Sites Realize Near-Unity CO Selectivity for Electrochemical CO2 Reduction.

    PubMed

    Li, Xiaogang; Bi, Wentuan; Chen, Minglong; Sun, Yuexiang; Ju, Huanxin; Yan, Wensheng; Zhu, Junfa; Wu, Xiaojun; Chu, Wangsheng; Wu, Changzheng; Xie, Yi

    2017-10-25

    Electrochemical reduction of carbon dioxide (CO 2 ) to value-added carbon products is a promising approach to reduce CO 2 levels and mitigate the energy crisis. However, poor product selectivity is still a major obstacle to the development of CO 2 reduction. Here we demonstrate exclusive Ni-N 4 sites through a topo-chemical transformation strategy, bringing unprecedentedly high activity and selectivity for CO 2 reduction. Topo-chemical transformation by carbon layer coating successfully ensures preservation of the Ni-N 4 structure to a maximum extent and avoids the agglomeration of Ni atoms to particles, providing abundant active sites for the catalytic reaction. The Ni-N 4 structure exhibits excellent activity for electrochemical reduction of CO 2 with particularly high selectivity, achieving high faradaic efficiency over 90% for CO in the potential range from -0.5 to -0.9 V and gives a maximum faradaic efficiency of 99% at -0.81 V with a current density of 28.6 mA cm -2 . We anticipate exclusive catalytic sites will shed new light on the design of high-efficiency electrocatalysts for CO 2 reduction.

  3. Site-selective local fluorination of graphene induced by focused ion beam irradiation.

    PubMed

    Li, Hu; Daukiya, Lakshya; Haldar, Soumyajyoti; Lindblad, Andreas; Sanyal, Biplab; Eriksson, Olle; Aubel, Dominique; Hajjar-Garreau, Samar; Simon, Laurent; Leifer, Klaus

    2016-01-29

    The functionalization of graphene remains an important challenge for numerous applications expected by this fascinating material. To keep advantageous properties of graphene after modification or functionalization of its structure, local approaches are a promising road. A novel technique is reported here that allows precise site-selective fluorination of graphene. The basic idea of this approach consists in the local radicalization of graphene by focused ion beam (FIB) irradiation and simultaneous introduction of XeF2 gas. A systematic series of experiments were carried out to outline the relation between inserted defect creation and the fluorination process. Based on a subsequent X-ray photoelectron spectroscopy (XPS) analysis, a 6-fold increase of the fluorine concentration on graphene under simultaneous irradiation was observed when compared to fluorination under normal conditions. The fluorine atoms are predominately localized at the defects as indicated from scanning tunneling microscopy (STM). The experimental findings are confirmed by density functional theory which predicts a strong increase of the binding energy of fluorine atoms when bound to the defect sites. The developed technique allows for local fluorination of graphene without using resists and has potential to be a general enabler of site-selective functionalization of graphene using a wide range of gases.

  4. Site-selective local fluorination of graphene induced by focused ion beam irradiation

    PubMed Central

    Li, Hu; Daukiya, Lakshya; Haldar, Soumyajyoti; Lindblad, Andreas; Sanyal, Biplab; Eriksson, Olle; Aubel, Dominique; Hajjar-Garreau, Samar; Simon, Laurent; Leifer, Klaus

    2016-01-01

    The functionalization of graphene remains an important challenge for numerous applications expected by this fascinating material. To keep advantageous properties of graphene after modification or functionalization of its structure, local approaches are a promising road. A novel technique is reported here that allows precise site-selective fluorination of graphene. The basic idea of this approach consists in the local radicalization of graphene by focused ion beam (FIB) irradiation and simultaneous introduction of XeF2 gas. A systematic series of experiments were carried out to outline the relation between inserted defect creation and the fluorination process. Based on a subsequent X-ray photoelectron spectroscopy (XPS) analysis, a 6-fold increase of the fluorine concentration on graphene under simultaneous irradiation was observed when compared to fluorination under normal conditions. The fluorine atoms are predominately localized at the defects as indicated from scanning tunneling microscopy (STM). The experimental findings are confirmed by density functional theory which predicts a strong increase of the binding energy of fluorine atoms when bound to the defect sites. The developed technique allows for local fluorination of graphene without using resists and has potential to be a general enabler of site-selective functionalization of graphene using a wide range of gases. PMID:26822900

  5. Site-selective local fluorination of graphene induced by focused ion beam irradiation

    NASA Astrophysics Data System (ADS)

    Li, Hu; Daukiya, Lakshya; Haldar, Soumyajyoti; Lindblad, Andreas; Sanyal, Biplab; Eriksson, Olle; Aubel, Dominique; Hajjar-Garreau, Samar; Simon, Laurent; Leifer, Klaus

    2016-01-01

    The functionalization of graphene remains an important challenge for numerous applications expected by this fascinating material. To keep advantageous properties of graphene after modification or functionalization of its structure, local approaches are a promising road. A novel technique is reported here that allows precise site-selective fluorination of graphene. The basic idea of this approach consists in the local radicalization of graphene by focused ion beam (FIB) irradiation and simultaneous introduction of XeF2 gas. A systematic series of experiments were carried out to outline the relation between inserted defect creation and the fluorination process. Based on a subsequent X-ray photoelectron spectroscopy (XPS) analysis, a 6-fold increase of the fluorine concentration on graphene under simultaneous irradiation was observed when compared to fluorination under normal conditions. The fluorine atoms are predominately localized at the defects as indicated from scanning tunneling microscopy (STM). The experimental findings are confirmed by density functional theory which predicts a strong increase of the binding energy of fluorine atoms when bound to the defect sites. The developed technique allows for local fluorination of graphene without using resists and has potential to be a general enabler of site-selective functionalization of graphene using a wide range of gases.

  6. Discovery and Optimization of a Novel Series of Highly Selective JAK1 Kinase Inhibitors.

    PubMed

    Grimster, Neil P; Anderson, Erica; Alimzhanov, Marat; Bebernitz, Geraldine; Bell, Kirsten; Chuaqui, Claudio; Deegan, Tracy; Ferguson, Andrew D; Gero, Thomas; Harsch, Andreas; Huszar, Dennis; Kawatkar, Aarti; Kettle, Jason Grant; Lyne, Paul D; Read, Jon A; Rivard Costa, Caroline; Ruston, Linette; Schroeder, Patricia; Shi, Jie; Su, Qibin; Throner, Scott; Toader, Dorin; Vasbinder, Melissa Marie; Woessner, Richard; Wang, Haixia; Wu, Allan; Ye, Minwei; Zheng, Weijia; Zinda, Michael

    2018-06-01

    Herein, we report the discovery and characterization of a novel series of pyrimidine based JAK1 inhibitors. Optimization of these ATP competitive compounds was guided by X-ray crystallography and a structure-based drug design approach, focusing on selectivity, potency, and pharmaceutical properties. The best compound, 24, displayed remarkable JAK1 selectivity (~1000-fold vs JAK2,3 and TYK2), as well as a good kinase selectivity profile. Moreover, a dose-dependent reduction in pSTAT3, a downstream marker of JAK1 inhibition, was observed when 24 was examined in vivo.

  7. 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.

  8. 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.

  9. Optimization Techniques for Design Problems in Selected Areas in WSNs: A Tutorial

    PubMed Central

    Ibrahim, Ahmed; Alfa, Attahiru

    2017-01-01

    This paper is intended to serve as an overview of, and mostly a tutorial to illustrate, the optimization techniques used in several different key design aspects that have been considered in the literature of wireless sensor networks (WSNs). It targets the researchers who are new to the mathematical optimization tool, and wish to apply it to WSN design problems. We hence divide the paper into two main parts. One part is dedicated to introduce optimization theory and an overview on some of its techniques that could be helpful in design problem in WSNs. In the second part, we present a number of design aspects that we came across in the WSN literature in which mathematical optimization methods have been used in the design. For each design aspect, a key paper is selected, and for each we explain the formulation techniques and the solution methods implemented. We also provide in-depth analyses and assessments of the problem formulations, the corresponding solution techniques and experimental procedures in some of these papers. The analyses and assessments, which are provided in the form of comments, are meant to reflect the points that we believe should be taken into account when using optimization as a tool for design purposes. PMID:28763039

  10. Optimization Techniques for Design Problems in Selected Areas in WSNs: A Tutorial.

    PubMed

    Ibrahim, Ahmed; Alfa, Attahiru

    2017-08-01

    This paper is intended to serve as an overview of, and mostly a tutorial to illustrate, the optimization techniques used in several different key design aspects that have been considered in the literature of wireless sensor networks (WSNs). It targets the researchers who are new to the mathematical optimization tool, and wish to apply it to WSN design problems. We hence divide the paper into two main parts. One part is dedicated to introduce optimization theory and an overview on some of its techniques that could be helpful in design problem in WSNs. In the second part, we present a number of design aspects that we came across in the WSN literature in which mathematical optimization methods have been used in the design. For each design aspect, a key paper is selected, and for each we explain the formulation techniques and the solution methods implemented. We also provide in-depth analyses and assessments of the problem formulations, the corresponding solution techniques and experimental procedures in some of these papers. The analyses and assessments, which are provided in the form of comments, are meant to reflect the points that we believe should be taken into account when using optimization as a tool for design purposes.

  11. 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).

  12. Diverse Actions and Target-Site Selectivity of Neonicotinoids: Structural Insights

    PubMed Central

    Matsuda, Kazuhiko; Kanaoka, Satoshi; Akamatsu, Miki; Sattelle, David B.

    2009-01-01

    The nicotinic acetylcholine receptors (nAChRs) are targets for human and veterinary medicines as well as insecticides. Subtype-selectivity among the diverse nAChR family members is important for medicines targeting particular disorders, and pest-insect selectivity is essential for the development of safer, environmentally acceptable insecticides. Neonicotinoid insecticides selectively targeting insect nAChRs have important applications in crop protection and animal health. Members of this class exhibit strikingly diverse actions on their nAChR targets. Here we review the chemistry and diverse actions of neonicotinoids on insect and mammalian nAChRs. Electrophysiological studies on native nAChRs and on wild-type and mutagenized recombinant nAChRs have shown that basic residues particular to loop D of insect nAChRs are likely to interact electrostatically with the nitro group of neonicotinoids. In 2008, the crystal structures were published showing neonicotinoids docking into the acetylcholine binding site of molluscan acetylcholine binding proteins with homology to the ligand binding domain (LBD) of nAChRs. The crystal structures showed that 1) glutamine in loop D, corresponding to the basic residues of insect nAChRs, hydrogen bonds with the NO2 group of imidacloprid and 2) neonicotinoid-unique stacking and CH-π bonds at the LBD. A neonicotinoid-resistant strain obtained by laboratory-screening has been found to result from target site mutations, and possible reasons for this are also suggested by the crystal structures. The prospects of designing neonicotinoids that are safe not only for mammals but also for beneficial insects such as honey bees (Apis mellifera) are discussed in terms of interactions with non-α nAChR subunits. PMID:19321668

  13. Determining Optimal Location and Numbers of Sample Transects for Characterization of UXO Sites

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

    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 ofmore » 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

  14. Superpredator proximity and landscape characteristics alters nest site selection and breeding success of a subordinate predator.

    PubMed

    Atuo, Fidelis Akunke; O'Connell, Timothy John

    2018-03-01

    Selecting nesting habitat that minimizes predation risk but maximizes foraging success is one of the most important decisions in avian life history. This takes on added complexity when a predator is faced with the challenge of avoiding fellow predators. We assessed the importance of local and landscape vegetation, food abundance, and predation risk on nest site selection and nest survival in a subordinate raptor (Mississippi Kite; Ictinia mississippiensis) nesting in proximity to two superpredators, Red-tailed hawk (Buteo jamaicensis) and Great horned owl (Bubo virginianus). All three species nested in trees in a grassland landscape. In this landscape, kites favored upland trees and shrubs, avoiding their more typical riparian forest association elsewhere in the species' range. Compared to random conditions, kites selected nest sites with high tree density and more closed canopy in the surrounding area. Mississippi Kite selection was not related to food abundance but could be explained by the presence of superpredators (i.e., hawks and owls) selecting riparian woodland for their nests. Nest survival declined with proximity to superpredator nesting sites. Overall, our study demonstrates how landscape structure and superior predators shapes predation risk for subordinate predators. Our results emphasize the importance of spatial heterogeneity in presenting opportunities for subordinate predators to coexist in a landscape with important superpredators.

  15. Inverse-optimized 3D conformal planning: Minimizing complexity while achieving equivalence with beamlet IMRT in multiple clinical sites

    PubMed Central

    Fraass, Benedick A.; Steers, Jennifer M.; Matuszak, Martha M.; McShan, Daniel L.

    2012-01-01

    Purpose: Inverse planned intensity modulated radiation therapy (IMRT) has helped many centers implement highly conformal treatment planning with beamlet-based techniques. The many comparisons between IMRT and 3D conformal (3DCRT) plans, however, have been limited because most 3DCRT plans are forward-planned while IMRT plans utilize inverse planning, meaning both optimization and delivery techniques are different. This work avoids that problem by comparing 3D plans generated with a unique inverse planning method for 3DCRT called inverse-optimized 3D (IO-3D) conformal planning. Since IO-3D and the beamlet IMRT to which it is compared use the same optimization techniques, cost functions, and plan evaluation tools, direct comparisons between IMRT and simple, optimized IO-3D plans are possible. Though IO-3D has some similarity to direct aperture optimization (DAO), since it directly optimizes the apertures used, IO-3D is specifically designed for 3DCRT fields (i.e., 1–2 apertures per beam) rather than starting with IMRT-like modulation and then optimizing aperture shapes. The two algorithms are very different in design, implementation, and use. The goals of this work include using IO-3D to evaluate how close simple but optimized IO-3D plans come to nonconstrained beamlet IMRT, showing that optimization, rather than modulation, may be the most important aspect of IMRT (for some sites). Methods: The IO-3D dose calculation and optimization functionality is integrated in the in-house 3D planning/optimization system. New features include random point dose calculation distributions, costlet and cost function capabilities, fast dose volume histogram (DVH) and plan evaluation tools, optimization search strategies designed for IO-3D, and an improved, reimplemented edge/octree calculation algorithm. The IO-3D optimization, in distinction to DAO, is designed to optimize 3D conformal plans (one to two segments per beam) and optimizes MLC segment shapes and weights with various

  16. Bed site selection by a subordinate predator: an example with the cougar (Puma concolor) in the Greater Yellowstone Ecosystem.

    PubMed

    Kusler, Anna; Elbroch, L Mark; Quigley, Howard; Grigione, Melissa

    2017-01-01

    As technology has improved, our ability to study cryptic animal behavior has increased. Bed site selection is one such example. Among prey species, bed site selection provides thermoregulatory benefits and mitigates predation risk, and may directly influence survival. We conducted research to test whether a subordinate carnivore also selected beds with similar characteristics in an ecosystem supporting a multi-species guild of competing predators. We employed a model comparison approach in which we tested whether cougar ( Puma concolor ) bed site attributes supported the thermoregulatory versus the predator avoidance hypotheses, or exhibited characteristics supporting both hypotheses. Between 2012-2016, we investigated 599 cougar bed sites in the Greater Yellowstone Ecosystem and examined attributes at two scales: the landscape (second-order, n  = 599) and the microsite (fourth order, n  = 140). At the landscape scale, cougars selected bed sites in winter that supported both the thermoregulatory and predator avoidance hypotheses: bed sites were on steeper slopes but at lower elevations, closer to the forest edge, away from sagebrush and meadow habitat types, and on southern, eastern, and western-facing slopes. In the summer, bed attributes supported the predator avoidance hypothesis over the thermoregulation hypothesis: beds were closer to forest edges, away from sagebrush and meadow habitat classes, and on steeper slopes. At the microsite scale, cougar bed attributes in both the winter and summer supported both the predator avoidance and thermoregulatory hypotheses: they selected bed sites with high canopy cover, high vegetative concealment, and in a rugged habitat class characterized by cliff bands and talus fields. We found that just like prey species, a subordinate predator selected bed sites that facilitated both thermoregulatory and anti-predator functions. In conclusion, we believe that measuring bed site attributes may provide a novel means of measuring

  17. MaNGA: Target selection and Optimization

    NASA Astrophysics Data System (ADS)

    Wake, David

    2015-01-01

    The 6-year SDSS-IV MaNGA survey will measure spatially resolved spectroscopy for 10,000 nearby galaxies using the Sloan 2.5m telescope and the BOSS spectrographs with a new fiber arrangement consisting of 17 individually deployable IFUs. We present the simultaneous design of the target selection and IFU size distribution to optimally meet our targeting requirements. The requirements for the main samples were to use simple cuts in redshift and magnitude to produce an approximately flat number density of targets as a function of stellar mass, ranging from 1x109 to 1x1011 M⊙, and radial coverage to either 1.5 (Primary sample) or 2.5 (Secondary sample) effective radii, while maximizing S/N and spatial resolution. In addition we constructed a 'Color-Enhanced' sample where we required 25% of the targets to have an approximately flat number density in the color and mass plane. We show how these requirements are met using simple absolute magnitude (and color) dependent redshift cuts applied to an extended version of the NASA Sloan Atlas (NSA), how this determines the distribution of IFU sizes and the resulting properties of the MaNGA sample.

  18. MaNGA: Target selection and Optimization

    NASA Astrophysics Data System (ADS)

    Wake, David

    2016-01-01

    The 6-year SDSS-IV MaNGA survey will measure spatially resolved spectroscopy for 10,000 nearby galaxies using the Sloan 2.5m telescope and the BOSS spectrographs with a new fiber arrangement consisting of 17 individually deployable IFUs. We present the simultaneous design of the target selection and IFU size distribution to optimally meet our targeting requirements. The requirements for the main samples were to use simple cuts in redshift and magnitude to produce an approximately flat number density of targets as a function of stellar mass, ranging from 1x109 to 1x1011 M⊙, and radial coverage to either 1.5 (Primary sample) or 2.5 (Secondary sample) effective radii, while maximizing S/N and spatial resolution. In addition we constructed a "Color-Enhanced" sample where we required 25% of the targets to have an approximately flat number density in the color and mass plane. We show how these requirements are met using simple absolute magnitude (and color) dependent redshift cuts applied to an extended version of the NASA Sloan Atlas (NSA), how this determines the distribution of IFU sizes and the resulting properties of the MaNGA sample.

  19. Mars Mission Optimization Based on Collocation of Resources

    NASA Technical Reports Server (NTRS)

    Chamitoff, G. E.; James, G. H.; Barker, D. C.; Dershowitz, A. L.

    2003-01-01

    This paper presents a powerful approach for analyzing Martian data and for optimizing mission site selection based on resource collocation. This approach is implemented in a program called PROMT (Planetary Resource Optimization and Mapping Tool), which provides a wide range of analysis and display functions that can be applied to raw data or imagery. Thresholds, contours, custom algorithms, and graphical editing are some of the various methods that can be used to process data. Output maps can be created to identify surface regions on Mars that meet any specific criteria. The use of this tool for analyzing data, generating maps, and collocating features is demonstrated using data from the Mars Global Surveyor and the Odyssey spacecraft. The overall mission design objective is to maximize a combination of scientific return and self-sufficiency based on utilization of local materials. Landing site optimization involves maximizing accessibility to collocated science and resource features within a given mission radius. Mission types are categorized according to duration, energy resources, and in-situ resource utilization. Optimization results are shown for a number of mission scenarios.

  20. Multiple criteria approach to site selection of radioactive waste disposal facility in the Republic of Croatia

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

    Schaller, A.; Skanata, D.

    1995-12-31

    Site selection approach to radioactive waste disposal facility, which is under way in Croatia, is presented in the paper. This approach is based on application of certain relevant terrestrial and technical criteria in the site selection process. Basic documentation used for this purpose are regional planning documents prepared by the Regional Planning Institute of Croatia. The basic result of research described in the paper is the proposal of several potential areas which are suitable for siting a radioactive waste repository. All relevant conclusions are based on both data groups -- generic and on-field experienced (measured). Out of a dozen potentialmore » areas, four have been chosen as representative by the authors. The presented comparative analysis was made by means of the VISA II computer code, developed by the V. Belton and SPV Software Products. The code was donated to the APO by the IAEA. The main objective of the paper is to initiate and facilitate further discussions on possible ways of evaluation and comparison of potential areas for sitting of radioactive waste repository in this country, as well as to provide additional contributions to the current site selection process in the Republic of Croatia.« less

  1. Improved site-specific recombinase-based method to produce selectable marker- and vector-backbone-free transgenic cells

    NASA Astrophysics Data System (ADS)

    Yu, Yuan; Tong, Qi; Li, Zhongxia; Tian, Jinhai; Wang, Yizhi; Su, Feng; Wang, Yongsheng; Liu, Jun; Zhang, Yong

    2014-02-01

    PhiC31 integrase-mediated gene delivery has been extensively used in gene therapy and animal transgenesis. However, random integration events are observed in phiC31-mediated integration in different types of mammalian cells; as a result, the efficiencies of pseudo attP site integration and evaluation of site-specific integration are compromised. To improve this system, we used an attB-TK fusion gene as a negative selection marker, thereby eliminating random integration during phiC31-mediated transfection. We also excised the selection system and plasmid bacterial backbone by using two other site-specific recombinases, Cre and Dre. Thus, we generated clean transgenic bovine fetal fibroblast cells free of selectable marker and plasmid bacterial backbone. These clean cells were used as donor nuclei for somatic cell nuclear transfer (SCNT), indicating a similar developmental competence of SCNT embryos to that of non-transgenic cells. Therefore, the present gene delivery system facilitated the development of gene therapy and agricultural biotechnology.

  2. Distributed Energy Resources On-Site Optimization for Commercial Buildings with Electric and Thermal Storage Technologies

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

    Lacommare, Kristina S H; Stadler, Michael; Aki, Hirohisa

    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 problemmore » 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.« less

  3. Optimizing selective cutting strategies for maximum carbon stocks and yield of Moso bamboo forest using BIOME-BGC model.

    PubMed

    Mao, Fangjie; Zhou, Guomo; Li, Pingheng; Du, Huaqiang; Xu, Xiaojun; Shi, Yongjun; Mo, Lufeng; Zhou, Yufeng; Tu, Guoqing

    2017-04-15

    The selective cutting method currently used in Moso bamboo forests has resulted in a reduction of stand productivity and carbon sequestration capacity. Given the time and labor expense involved in addressing this problem manually, simulation using an ecosystem model is the most suitable approach. The BIOME-BGC model was improved to suit managed Moso bamboo forests, which was adapted to include age structure, specific ecological processes and management measures of Moso bamboo forest. A field selective cutting experiment was done in nine plots with three cutting intensities (high-intensity, moderate-intensity and low-intensity) during 2010-2013, and biomass of these plots was measured for model validation. Then four selective cutting scenarios were simulated by the improved BIOME-BGC model to optimize the selective cutting timings, intervals, retained ages and intensities. The improved model matched the observed aboveground carbon density and yield of different plots, with a range of relative error from 9.83% to 15.74%. The results of different selective cutting scenarios suggested that the optimal selective cutting measure should be cutting 30% culms of age 6, 80% culms of age 7, and all culms thereafter (above age 8) in winter every other year. The vegetation carbon density and harvested carbon density of this selective cutting method can increase by 74.63% and 21.5%, respectively, compared with the current selective cutting measure. The optimized selective cutting measure developed in this study can significantly promote carbon density, yield, and carbon sink capacity in Moso bamboo forests. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Analysis and selection of optimal function implementations in massively parallel computer

    DOEpatents

    Archer, Charles Jens [Rochester, MN; Peters, Amanda [Rochester, MN; Ratterman, Joseph D [Rochester, MN

    2011-05-31

    An apparatus, program product and method optimize the operation of a parallel computer system by, in part, collecting performance data for a set of implementations of a function capable of being executed on the parallel computer system based upon the execution of the set of implementations under varying input parameters in a plurality of input dimensions. The collected performance data may be used to generate selection program code that is configured to call selected implementations of the function in response to a call to the function under varying input parameters. The collected performance data may be used to perform more detailed analysis to ascertain the comparative performance of the set of implementations of the function under the varying input parameters.

  5. Disposal Site Selection Technical Appendix. Phase 2. (North and South Puget Sound)

    DTIC Science & Technology

    1989-09-01

    target species were sampled at each site. This reflects in part variation in the habitat preferences of the selected target species. The ichthyofauna ...Region. Mar. Geol., 64:291-312. Carr, W.E.S. and C.A. Adams. 1973. Food Habits of Juvenile Marine Fishes Occupying Seagrass Beds in the Estuarine Zone

  6. A new approach to optimal selection of services in health care organizations.

    PubMed

    Adolphson, D L; Baird, M L; Lawrence, K D

    1991-01-01

    A new reimbursement policy adopted by Medicare in 1983 caused financial difficulties for many hospitals and health care organizations. Several organizations responded to these difficulties by developing systems to carefully measure their costs of providing services. The purpose of such systems was to provide relevant information about the profitability of hospital services. This paper presents a new method of making hospital service selection decisions: it is based on an optimization model that avoids arbitrary cost allocations as a basis for computing the costs of offering a given service. The new method provides more reliable information about which services are profitable or unprofitable, and it provides an accurate measure of the degree to which a service is profitable or unprofitable. The new method also provides useful information about the sensitivity of the optimal decision to changes in costs and revenues. Specialized algorithms for the optimization model lead to very efficient implementation of the method, even for the largest health care organizations.

  7. Optimal Electrode Selection for Electrical Resistance Tomography in Carbon Fiber Reinforced Polymer Composites

    PubMed Central

    Escalona Galvis, Luis Waldo; Diaz-Montiel, Paulina; Venkataraman, Satchi

    2017-01-01

    Electrical Resistance Tomography (ERT) offers a non-destructive evaluation (NDE) technique that takes advantage of the inherent electrical properties in carbon fiber reinforced polymer (CFRP) composites for internal damage characterization. This paper investigates a method of optimum selection of sensing configurations for delamination detection in thick cross-ply laminates using ERT. Reduction in the number of sensing locations and measurements is necessary to minimize hardware and computational effort. The present work explores the use of an effective independence (EI) measure originally proposed for sensor location optimization in experimental vibration modal analysis. The EI measure is used for selecting the minimum set of resistance measurements among all possible combinations resulting from selecting sensing electrode pairs. Singular Value Decomposition (SVD) is applied to obtain a spectral representation of the resistance measurements in the laminate for subsequent EI based reduction to take place. The electrical potential field in a CFRP laminate is calculated using finite element analysis (FEA) applied on models for two different laminate layouts considering a set of specified delamination sizes and locations with two different sensing arrangements. The effectiveness of the EI measure in eliminating redundant electrode pairs is demonstrated by performing inverse identification of damage using the full set and the reduced set of resistance measurements. This investigation shows that the EI measure is effective for optimally selecting the electrode pairs needed for resistance measurements in ERT based damage detection. PMID:28772485

  8. Fuzzy Random λ-Mean SAD Portfolio Selection Problem: An Ant Colony Optimization Approach

    NASA Astrophysics Data System (ADS)

    Thakur, Gour Sundar Mitra; Bhattacharyya, Rupak; Mitra, Swapan Kumar

    2010-10-01

    To reach the investment goal, one has to select a combination of securities among different portfolios containing large number of securities. Only the past records of each security do not guarantee the future return. As there are many uncertain factors which directly or indirectly influence the stock market and there are also some newer stock markets which do not have enough historical data, experts' expectation and experience must be combined with the past records to generate an effective portfolio selection model. In this paper the return of security is assumed to be Fuzzy Random Variable Set (FRVS), where returns are set of random numbers which are in turn fuzzy numbers. A new λ-Mean Semi Absolute Deviation (λ-MSAD) portfolio selection model is developed. The subjective opinions of the investors to the rate of returns of each security are taken into consideration by introducing a pessimistic-optimistic parameter vector λ. λ-Mean Semi Absolute Deviation (λ-MSAD) model is preferred as it follows absolute deviation of the rate of returns of a portfolio instead of the variance as the measure of the risk. As this model can be reduced to Linear Programming Problem (LPP) it can be solved much faster than quadratic programming problems. Ant Colony Optimization (ACO) is used for solving the portfolio selection problem. ACO is a paradigm for designing meta-heuristic algorithms for combinatorial optimization problem. Data from BSE is used for illustration.

  9. A fast inverse treatment planning strategy facilitating optimized catheter selection in image-guided high-dose-rate interstitial gynecologic brachytherapy.

    PubMed

    Guthier, Christian V; Damato, Antonio L; Hesser, Juergen W; Viswanathan, Akila N; Cormack, Robert A

    2017-12-01

    Interstitial high-dose rate (HDR) brachytherapy is an important therapeutic strategy for the treatment of locally advanced gynecologic (GYN) cancers. The outcome of this therapy is determined by the quality of dose distribution achieved. This paper focuses on a novel yet simple heuristic for catheter selection for GYN HDR brachytherapy and their comparison against state of the art optimization strategies. The proposed technique is intended to act as a decision-supporting tool to select a favorable needle configuration. The presented heuristic for catheter optimization is based on a shrinkage-type algorithm (SACO). It is compared against state of the art planning in a retrospective study of 20 patients who previously received image-guided interstitial HDR brachytherapy using a Syed Neblett template. From those plans, template orientation and position are estimated via a rigid registration of the template with the actual catheter trajectories. All potential straight trajectories intersecting the contoured clinical target volume (CTV) are considered for catheter optimization. Retrospectively generated plans and clinical plans are compared with respect to dosimetric performance and optimization time. All plans were generated with one single run of the optimizer lasting 0.6-97.4 s. Compared to manual optimization, SACO yields a statistically significant (P ≤ 0.05) improved target coverage while at the same time fulfilling all dosimetric constraints for organs at risk (OARs). Comparing inverse planning strategies, dosimetric evaluation for SACO and "hybrid inverse planning and optimization" (HIPO), as gold standard, shows no statistically significant difference (P > 0.05). However, SACO provides the potential to reduce the number of used catheters without compromising plan quality. The proposed heuristic for needle selection provides fast catheter selection with optimization times suited for intraoperative treatment planning. Compared to manual optimization, the

  10. 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

  11. Optimization of protease-inhibitor interactions by randomizing adventitious contacts

    PubMed Central

    Komiyama, Tomoko; VanderLugt, Bryan; Fugère, Martin; Day, Robert; Kaufman, Randal J.; Fuller, Robert S.

    2003-01-01

    Polypeptide protease inhibitors are often found to inhibit targets with which they did not coevolve, as in the case of high-affinity inhibition of bacterial subtilisin by the leech inhibitor eglin c. Two kinds of contacts exist in such complexes: (i) reactive site loop-active site contacts and (ii) interactions outside of these that form the broader enzyme-inhibitor interface. We hypothesized that the second class of “adventitious” contacts could be optimized to generate significant increases in affinity for a target enzyme or discrimination of an inhibitor for closely related target proteases. We began with a modified eglin c, Arg-42–Arg-45–eglin, in which the reactive site loop had been optimized for subtilisin-related processing proteases of the Kex2/furin family. We randomized 10 potential adventitious contact residues and screened for inhibition of soluble human furin. Substitutions at one of these sites, Y49, were also screened against yeast Kex2 and human PC7. These screens identified not only variants that exhibited increased affinity (up to 20-fold), but also species that exhibited enhanced selectivity, that is, increased discrimination between the target enzymes (up to 41-fold for furin versus PC7 and 20-fold for PC7 versus furin). One variant, Asp-49–Arg-42–Arg-45–eglin, exhibited a Ki of 310 pM for furin and blocked furin-dependent processing of von Willebrand factor in COS-1 cells when added to the culture medium of the cells. The exploitation of adventitious contact sites may provide a versatile technique for developing potent, selective inhibitors for newly discovered proteases and could in principle be applied to optimize numerous protein–protein interactions. PMID:12832612

  12. A Compensatory Approach to Optimal Selection with Mastery Scores. Research Report 94-2.

    ERIC Educational Resources Information Center

    van der Linden, Wim J.; Vos, Hans J.

    This paper presents some Bayesian theories of simultaneous optimization of decision rules for test-based decisions. Simultaneous decision making arises when an institution has to make a series of selection, placement, or mastery decisions with respect to subjects from a population. An obvious example is the use of individualized instruction in…

  13. APASdb: a database describing alternative poly(A) sites and selection of heterogeneous cleavage sites downstream of poly(A) signals

    PubMed Central

    You, Leiming; Wu, Jiexin; Feng, Yuchao; Fu, Yonggui; Guo, Yanan; Long, Liyuan; Zhang, Hui; Luan, Yijie; Tian, Peng; Chen, Liangfu; Huang, Guangrui; Huang, Shengfeng; Li, Yuxin; Li, Jie; Chen, Chengyong; Zhang, Yaqing; Chen, Shangwu; Xu, Anlong

    2015-01-01

    Increasing amounts of genes have been shown to utilize alternative polyadenylation (APA) 3′-processing sites depending on the cell and tissue type and/or physiological and pathological conditions at the time of processing, and the construction of genome-wide database regarding APA is urgently needed for better understanding poly(A) site selection and APA-directed gene expression regulation for a given biology. Here we present a web-accessible database, named APASdb (http://mosas.sysu.edu.cn/utr), which can visualize the precise map and usage quantification of different APA isoforms for all genes. The datasets are deeply profiled by the sequencing alternative polyadenylation sites (SAPAS) method capable of high-throughput sequencing 3′-ends of polyadenylated transcripts. Thus, APASdb details all the heterogeneous cleavage sites downstream of poly(A) signals, and maintains near complete coverage for APA sites, much better than the previous databases using conventional methods. Furthermore, APASdb provides the quantification of a given APA variant among transcripts with different APA sites by computing their corresponding normalized-reads, making our database more useful. In addition, APASdb supports URL-based retrieval, browsing and display of exon-intron structure, poly(A) signals, poly(A) sites location and usage reads, and 3′-untranslated regions (3′-UTRs). Currently, APASdb involves APA in various biological processes and diseases in human, mouse and zebrafish. PMID:25378337

  14. Solubilization and characterization of haloperidol-sensitive (+)-( sup 3 H)SKF-10,047 binding sites (sigma sites) from rat liver membranes

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

    McCann, D.J.; Su, T.P.

    1991-05-01

    The zwitterionic detergent 3-((3-cholamidopropyl)dimethylamino)-1-propanesulfonate (CHAPS) produced optimal solubilization of (+)-({sup 3}H)SKF-10,047 binding sites from rat liver membranes at a concentration of 0.2%, well below the critical micellular concentration of the detergent. The pharmacological selectivity of the liver (+)-({sup 3}H)SKF-10,047 binding sites corresponds to that of sigma sites from rat and guinea pig brain. When the affinities of 18 different drugs at (+)-({sup 3}H)SKF-10,047 binding sites in membranes and solubilized preparations were compared, a correlation coefficient of 0.99 and a slope of 1.03 were obtained, indicating that the pharmacological selectivity of rat liver sigma sites is retained after solubilization. In addition,more » the binding of 20 nM ({sup 3}H)progesterone to solubilized rat liver preparations was found to exhibit a pharmacological selectivity appropriate for sigma sites. A stimulatory effect of phenytoin on (+)-({sup 3}H)SKF-10,047 binding to sigma sites persisted after solubilization. When the solubilized preparation was subjected to molecular sizing chromatography, a single peak exhibiting specific (+)-({sup 3}H)SKF-10,047 binding was obtained. The binding activity of this peak was stimulated symmetrically when assays were performed in the presence of 300 microM phenytoin. The molecular weight of the CHAPS-solubilized sigma site complex was estimated to be 450,000 daltons. After solubilization with CHAPS, rat liver sigma sites were enriched to 12 pmol/mg of protein. The present results demonstrate a successful solubilization of sigma sites from rat liver membranes and provide direct evidence that the gonadal steroid progesterone binds to sigma sites. The results also suggest that the anticonvulsant phenytoin binds to an associated allosteric site on the sigma site complex.« less

  15. Short-term prey field lability constrains individual specialisation in resource selection and foraging site fidelity in a marine predator.

    PubMed

    Courbin, Nicolas; Besnard, Aurélien; Péron, Clara; Saraux, Claire; Fort, Jérôme; Perret, Samuel; Tornos, Jérémy; Grémillet, David

    2018-04-16

    Spatio-temporally stable prey distributions coupled with individual foraging site fidelity are predicted to favour individual resource specialisation. Conversely, predators coping with dynamic prey distributions should diversify their individual diet and/or shift foraging areas to increase net intake. We studied individual specialisation in Scopoli's shearwaters (Calonectris diomedea) from the highly dynamic Western Mediterranean, using daily prey distributions together with resource selection, site fidelity and trophic-level analyses. As hypothesised, we found dietary diversification, low foraging site fidelity and almost no individual specialisation in resource selection. Crucially, shearwaters switched daily foraging tactics, selecting areas with contrasting prey of varying trophic levels. Overall, information use and plastic resource selection of individuals with reduced short-term foraging site fidelity allow predators to overcome prey field lability. Our study is an essential step towards a better understanding of individual responses to enhanced environmental stochasticity driven by global changes, and of pathways favouring population persistence. © 2018 John Wiley & Sons Ltd/CNRS.

  16. Habitat selection in a rocky landscape: experimentally decoupling the influence of retreat site attributes from that of landscape features.

    PubMed

    Croak, Benjamin M; Pike, David A; Webb, Jonathan K; Shine, Richard

    2012-01-01

    Organisms selecting retreat sites may evaluate not only the quality of the specific shelter, but also the proximity of that site to resources in the surrounding area. Distinguishing between habitat selection at these two spatial scales is complicated by co-variation among microhabitat factors (i.e., the attributes of individual retreat sites often correlate with their proximity to landscape features). Disentangling this co-variation may facilitate the restoration or conservation of threatened systems. To experimentally examine the role of landscape attributes in determining retreat-site quality for saxicolous ectotherms, we deployed 198 identical artificial rocks in open (sun-exposed) sites on sandstone outcrops in southeastern Australia, and recorded faunal usage of those retreat sites over the next 29 months. Several landscape-scale attributes were associated with occupancy of experimental rocks, but different features were important for different species. For example, endangered broad-headed snakes (Hoplocephalus bungaroides) preferred retreat sites close to cliff edges, flat rock spiders (Hemicloea major) preferred small outcrops, and velvet geckos (Oedura lesueurii) preferred rocks close to the cliff edge with higher-than-average sun exposure. Standardized retreat sites can provide robust experimental data on the effects of landscape-scale attributes on retreat site selection, revealing interspecific divergences among sympatric taxa that use similar habitats.

  17. Environmental concern-based site screening of carbon dioxide geological storage in China.

    PubMed

    Cai, Bofeng; Li, Qi; Liu, Guizhen; Liu, Lancui; Jin, Taotao; Shi, Hui

    2017-08-08

    Environmental impacts and risks related to carbon dioxide (CO 2 ) capture and storage (CCS) projects may have direct effects on the decision-making process during CCS site selection. This paper proposes a novel method of environmental optimization for CCS site selection using China's ecological red line approach. Moreover, this paper established a GIS based spatial analysis model of environmental optimization during CCS site selection by a large database. The comprehensive data coverage of environmental elements and fine 1 km spatial resolution were used in the database. The quartile method was used for value assignment for specific indicators including the prohibited index and restricted index. The screening results show that areas classified as having high environmental suitability (classes III and IV) in China account for 620,800 km 2 and 156,600 km 2 , respectively, and are mainly distributed in Inner Mongolia, Qinghai and Xinjiang. The environmental suitability class IV areas of Bayingol Mongolian Autonomous Prefecture, Hotan Prefecture, Aksu Prefecture, Hulunbuir, Xilingol League and other prefecture-level regions not only cover large land areas, but also form a continuous area in the three provincial-level administrative units. This study may benefit the national macro-strategic deployment and implementation of CCS spatial layout and environmental management in China.

  18. Selectivity of externally facing ion-binding sites in the Na/K pump to alkali metals and organic cations

    PubMed Central

    Ratheal, Ian M.; Virgin, Gail K.; Yu, Haibo; Roux, Benoît; Gatto, Craig; Artigas, Pablo

    2010-01-01

    The Na/K pump is a P-type ATPase that exchanges three intracellular Na+ ions for two extracellular K+ ions through the plasmalemma of nearly all animal cells. The mechanisms involved in cation selection by the pump's ion-binding sites (site I and site II bind either Na+ or K+; site III binds only Na+) are poorly understood. We studied cation selectivity by outward-facing sites (high K+ affinity) of Na/K pumps expressed in Xenopus oocytes, under voltage clamp. Guanidinium+, methylguanidinium+, and aminoguanidinium+ produced two phenomena possibly reflecting actions at site III: (i) voltage-dependent inhibition (VDI) of outwardly directed pump current at saturating K+, and (ii) induction of pump-mediated, guanidinium-derivative–carried inward current at negative potentials without Na+ and K+. In contrast, formamidinium+ and acetamidinium+ induced K+-like outward currents. Measurement of ouabain-sensitive ATPase activity and radiolabeled cation uptake confirmed that these cations are external K+ congeners. Molecular dynamics simulations indicate that bound organic cations induce minor distortion of the binding sites. Among tested metals, only Li+ induced Na+-like VDI, whereas all metals tested except Na+ induced K+-like outward currents. Pump-mediated K+-like organic cation transport challenges the concept of rigid structural models in which ion specificity at site I and site II arises from a precise and unique arrangement of coordinating ligands. Furthermore, actions by guanidinium+ derivatives suggest that Na+ binds to site III in a hydrated form and that the inward current observed without external Na+ and K+ represents cation transport when normal occlusion at sites I and II is impaired. These results provide insights on external ion selectivity at the three binding sites. PMID:20937860

  19. Selective advantage of implementing optimal contributions selection and timescales for the convergence of long-term genetic contributions.

    PubMed

    Howard, David M; Pong-Wong, Ricardo; Knap, Pieter W; Kremer, Valentin D; Woolliams, John A

    2018-05-10

    Optimal contributions selection (OCS) provides animal breeders with a framework for maximising genetic gain for a predefined rate of inbreeding. Simulation studies have indicated that the source of the selective advantage of OCS is derived from breeding decisions being more closely aligned with estimates of Mendelian sampling terms ([Formula: see text]) of selection candidates, rather than estimated breeding values (EBV). This study represents the first attempt to assess the source of the selective advantage provided by OCS using a commercial pig population and by testing three hypotheses: (1) OCS places more emphasis on [Formula: see text] compared to EBV for determining which animals were selected as parents, (2) OCS places more emphasis on [Formula: see text] compared to EBV for determining which of those parents were selected to make a long-term genetic contribution (r), and (3) OCS places more emphasis on [Formula: see text] compared to EBV for determining the magnitude of r. The population studied also provided an opportunity to investigate the convergence of r over time. Selection intensity limited the number of males available for analysis, but females provided some evidence that the selective advantage derived from applying an OCS algorithm resulted from greater weighting being placed on [Formula: see text] during the process of decision-making. Male r were found to converge initially at a faster rate than female r, with approximately 90% convergence achieved within seven generations across both sexes. This study of commercial data provides some support to results from theoretical and simulation studies that the source of selective advantage from OCS comes from [Formula: see text]. The implication that genomic selection (GS) improves estimation of [Formula: see text] should allow for even greater genetic gains for a predefined rate of inbreeding, once the synergistic benefits of combining OCS and GS are realised.

  20. Martian resource locations: Identification and optimization

    NASA Astrophysics Data System (ADS)

    Chamitoff, Gregory; James, George; Barker, Donald; Dershowitz, Adam

    2005-04-01

    The identification and utilization of in situ Martian natural resources is the key to enable cost-effective long-duration missions and permanent human settlements on Mars. This paper presents a powerful software tool for analyzing Martian data from all sources, and for optimizing mission site selection based on resource collocation. This program, called Planetary Resource Optimization and Mapping Tool (PROMT), provides a wide range of analysis and display functions that can be applied to raw data or imagery. Thresholds, contours, custom algorithms, and graphical editing are some of the various methods that can be used to process data. Output maps can be created to identify surface regions on Mars that meet any specific criteria. The use of this tool for analyzing data, generating maps, and collocating features is demonstrated using data from the Mars Global Surveyor and the Odyssey spacecraft. The overall mission design objective is to maximize a combination of scientific return and self-sufficiency based on utilization of local materials. Landing site optimization involves maximizing accessibility to collocated science and resource features within a given mission radius. Mission types are categorized according to duration, energy resources, and in situ resource utilization. Preliminary optimization results are shown for a number of mission scenarios.

  1. A lesson for site-selective C-H functionalization on 2-pyridones: radical, organometallic, directing group and steric controls.

    PubMed

    Hirano, Koji; Miura, Masahiro

    2018-01-07

    A 2-pyridone ring is a frequently occurring subunit in natural products, biologically active compounds, and pharmaceutical targets. Thus, the selective synthesis of substituted 2-pyridone derivatives through decoration and/or formation of pyridone rings has been one of the important longstanding subjects in organic synthetic chemistry. This minireview focuses on recent advances in site-selective C-H functionalization on 2-pyridone. The reported procedures are categorized according to the site selectivity that is achieved, and the substrate scope, limitations, mechanism, and controlling factors are briefly summarized.

  2. An Ant Colony Optimization Based Feature Selection for Web Page Classification

    PubMed Central

    2014-01-01

    The increased popularity of the web has caused the inclusion of huge amount of information to the web, and as a result of this explosive information growth, automated web page classification systems are needed to improve search engines' performance. Web pages have a large number of features such as HTML/XML tags, URLs, hyperlinks, and text contents that should be considered during an automated classification process. The aim of this study is to reduce the number of features to be used to improve runtime and accuracy of the classification of web pages. In this study, we used an ant colony optimization (ACO) algorithm to select the best features, and then we applied the well-known C4.5, naive Bayes, and k nearest neighbor classifiers to assign class labels to web pages. We used the WebKB and Conference datasets in our experiments, and we showed that using the ACO for feature selection improves both accuracy and runtime performance of classification. We also showed that the proposed ACO based algorithm can select better features with respect to the well-known information gain and chi square feature selection methods. PMID:25136678

  3. An ant colony optimization based feature selection for web page classification.

    PubMed

    Saraç, Esra; Özel, Selma Ayşe

    2014-01-01

    The increased popularity of the web has caused the inclusion of huge amount of information to the web, and as a result of this explosive information growth, automated web page classification systems are needed to improve search engines' performance. Web pages have a large number of features such as HTML/XML tags, URLs, hyperlinks, and text contents that should be considered during an automated classification process. The aim of this study is to reduce the number of features to be used to improve runtime and accuracy of the classification of web pages. In this study, we used an ant colony optimization (ACO) algorithm to select the best features, and then we applied the well-known C4.5, naive Bayes, and k nearest neighbor classifiers to assign class labels to web pages. We used the WebKB and Conference datasets in our experiments, and we showed that using the ACO for feature selection improves both accuracy and runtime performance of classification. We also showed that the proposed ACO based algorithm can select better features with respect to the well-known information gain and chi square feature selection methods.

  4. Spectral bidirectional and hemispherical reflectance characteristics of selected sites in the Streletskaya steppe

    NASA Technical Reports Server (NTRS)

    Eck, Thomas F.; Deering, Donald W.

    1992-01-01

    Measurements of plant canopy bidirectional reflectance made by the PARABOLA (portable apparatus for rapid acquisition of bidirectional observations of the land and atmosphere) instrument in three spectral bands are analyzed for steppe grassland sites of differing productivity levels. The variation of spectral reflectance and the normalized difference vegetation index in the solar principal plane is presented. Comparisons are made with PARABOLA measurements from selected first ISLSCP field experiment (FIFE) grassland sites in the Konza prairie, Kansas. The Streletskaya steppe sites showed no strong hot spot reflectance, while this effect was present in some FIFE sites but absent in others. The hot spot effect seems to be dependent on canopy geometry and background reflectance characteristics of these sites. Spectral hemispherical reflectance was computed from the angular integration of the bidirectional measurements for the steppe sites. Total shortwave albedo was estimated from these hemispherical reflectance measurements and compared to albedo measured by pyranometers. The albedo estimates from PARABOLA were found to be approximately 12-17 percent higher than the pyranometer measurements.

  5. Nest site selection in native and exotic trees by Black-chinned Hummingbirds

    Treesearch

    Deborah M. Finch; Jeffrey Kelly

    2002-01-01

    We studied nest site selection and nesting success in Black-chinned Hummingbirds (Archilochus alexandri) along the middle Rio Grande, New Mexico. The study was conducted in association with an exotic woody plant removal program to determine whether the removal of exotic plants would affect wildlife populations and nesting success, either positively or negatively. Point...

  6. Feature Selection and Parameters Optimization of SVM Using Particle Swarm Optimization for Fault Classification in Power Distribution Systems.

    PubMed

    Cho, Ming-Yuan; Hoang, Thi Thom

    2017-01-01

    Fast and accurate fault classification is essential to power system operations. In this paper, in order to classify electrical faults in radial distribution systems, a particle swarm optimization (PSO) based support vector machine (SVM) classifier has been proposed. The proposed PSO based SVM classifier is able to select appropriate input features and optimize SVM parameters to increase classification accuracy. Further, a time-domain reflectometry (TDR) method with a pseudorandom binary sequence (PRBS) stimulus has been used to generate a dataset for purposes of classification. The proposed technique has been tested on a typical radial distribution network to identify ten different types of faults considering 12 given input features generated by using Simulink software and MATLAB Toolbox. The success rate of the SVM classifier is over 97%, which demonstrates the effectiveness and high efficiency of the developed method.

  7. 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. © 2016 S. Karger AG, Basel.

  8. Remote site-selective C–H activation directed by a catalytic bifunctional template

    PubMed Central

    Zhang, Zhipeng; Tanaka, Keita; Yu, Jin-Quan

    2017-01-01

    Converting C–H bonds directly into carbon-carbon and carbon-heteroatom bonds can significantly improve step-economy in synthesis by providing alternative disconnections to traditional functional group manipulations. In this context, directed C–H activation reactions have been extensively explored for regioselective functionalization1-5. Though applicability can be severely curtailed by distance from the directing group and the shape of the molecule, a number of approaches have been developed to overcome this limitation6-12. For instance, recognition of the distal and geometric relationship between an existing functional group and multiple C–H bonds has recently been exploited to achieve meta-selective C–H activation by use of a covalently attached U-shaped template13-17. However, stoichiometric installation of the template is not feasible in the absence of an appropriate functional group handle. Here we report the design of a catalytic, bifunctional template that binds heterocyclic substrate via reversible coordination instead of covalent linkage, allowing remote site-selective C–H olefination of heterocycles. The two metal centers coordinated to this template play different roles; anchoring substrates to the proximity of catalyst and cleaving the remote C–H bonds respectively. Using this strategy, we demonstrate remote site-selective C–H olefination of heterocyclic substrates which do not have functional group handles for covalently attaching templates. PMID:28273068

  9. 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.

  10. Memory control beliefs and everyday forgetfulness in adulthood: the effects of selection, optimization, and compensation strategies.

    PubMed

    Scheibner, Gunnar Benjamin; Leathem, Janet

    2012-01-01

    Controlling for age, gender, education, and self-rated health, the present study used regression analyses to examine the relationships between memory control beliefs and self-reported forgetfulness in the context of the meta-theory of Selective Optimization with Compensation (SOC). Findings from this online survey (N = 409) indicate that, among adult New Zealanders, a higher sense of memory control accounts for a 22.7% reduction in self-reported forgetfulness. Similarly, optimization was found to account for a 5% reduction in forgetfulness while the strategies of selection and compensation were not related to self-reports of forgetfulness. Optimization partially mediated the beneficial effects that some memory beliefs (e.g., believing that memory decline is inevitable and believing in the potential for memory improvement) have on forgetfulness. It was concluded that memory control beliefs are important predictors of self-reported forgetfulness while the support for the SOC model in the context of memory controllability and everyday forgetfulness is limited.

  11. A lesson for site-selective C–H functionalization on 2-pyridones: radical, organometallic, directing group and steric controls

    PubMed Central

    2017-01-01

    A 2-pyridone ring is a frequently occurring subunit in natural products, biologically active compounds, and pharmaceutical targets. Thus, the selective synthesis of substituted 2-pyridone derivatives through decoration and/or formation of pyridone rings has been one of the important longstanding subjects in organic synthetic chemistry. This minireview focuses on recent advances in site-selective C–H functionalization on 2-pyridone. The reported procedures are categorized according to the site selectivity that is achieved, and the substrate scope, limitations, mechanism, and controlling factors are briefly summarized. PMID:29629070

  12. 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

  13. Selection for avian leukosis virus integration sites determines the clonal progression of B-cell lymphomas

    PubMed Central

    Malhotra, Sanandan; Justice, James; Morgan, Robin

    2017-01-01

    Avian leukosis virus (ALV) is a simple retrovirus that causes a wide range of tumors in chickens, the most common of which are B-cell lymphomas. The viral genome integrates into the host genome and uses its strong promoter and enhancer sequences to alter the expression of nearby genes, frequently inducing tumors. In this study, we compare the preferences for ALV integration sites in cultured cells and in tumors, by analysis of over 87,000 unique integration sites. In tissue culture we observed integration was relatively random with slight preferences for genes, transcription start sites and CpG islands. We also observed a preference for integrations in or near expressed and spliced genes. The integration pattern in cultured cells changed over the course of selection for oncogenic characteristics in tumors. In comparison to tissue culture, ALV integrations are more highly selected for proximity to transcription start sites in tumors. There is also a significant selection of ALV integrations away from CpG islands in the highly clonally expanded cells in tumors. Additionally, we utilized a high throughput method to quantify the magnitude of clonality in different stages of tumorigenesis. An ALV-induced tumor carries between 700 and 3000 unique integrations, with an average of 2.3 to 4 copies of proviral DNA per infected cell. We observed increasing tumor clonality during progression of B-cell lymphomas and identified gene players (especially TERT and MYB) and biological processes involved in tumor progression. PMID:29099869

  14. Growth of 11 introduced tree species on selected forest sites in Hawaii

    Treesearch

    Michael G Buck; Roger H. Imoto

    1982-01-01

    Growth and volume data for trees on 25 plots reprsenting 11 introduced species in Hawaii were recorded during a 21-year period. Tree were measured at about 5-year intervals to determine overall growth and stand development. The sites selected were considered better-than-average in terms of elevation, amount of precipitation, and soil quality. Except for redwood, stands...

  15. 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.

  16. A Guide to School Site Selection.

    ERIC Educational Resources Information Center

    Georgia State Dept. of Education, Atlanta. Facilities Services Unit.

    This report presents the guidelines for site evaluation and approval as mandated by the state of Georgia. This guide may be used by the School Site Approval Committee when making school site evaluations for official approval, and also may be used by local school systems as they make preliminary determinations regarding the acceptability of school…

  17. Structural characterization of nonactive site, TrkA-selective kinase inhibitors

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

    Su, Hua-Poo; Rickert, Keith; Burlein, Christine

    Current therapies for chronic pain can have insufficient efficacy and lead to side effects, necessitating research of novel targets against pain. Although originally identified as an oncogene, Tropomyosin-related kinase A (TrkA) is linked to pain and elevated levels of NGF (the ligand for TrkA) are associated with chronic pain. Antibodies that block TrkA interaction with its ligand, NGF, are in clinical trials for pain relief. Here, we describe the identification of TrkA-specific inhibitors and the structural basis for their selectivity over other Trk family kinases. The X-ray structures reveal a binding site outside the kinase active site that uses residuesmore » from the kinase domain and the juxtamembrane region. Three modes of binding with the juxtamembrane region are characterized through a series of ligand-bound complexes. The structures indicate a critical pharmacophore on the compounds that leads to the distinct binding modes. The mode of interaction can allow TrkA selectivity over TrkB and TrkC or promiscuous, pan-Trk inhibition. This finding highlights the difficulty in characterizing the structure-activity relationship of a chemical series in the absence of structural information because of substantial differences in the interacting residues. These structures illustrate the flexibility of binding to sequences outside of—but adjacent to—the kinase domain of TrkA. This knowledge allows development of compounds with specificity for TrkA or the family of Trk proteins.« less

  18. Integrating expert knowledge in a GIS to optimize siting decisions for small-scale healthy food retail interventions.

    PubMed

    Sadler, Richard Casey

    2016-06-16

    The availability of healthy foods in a neighborhood remains a key determinant of diet and diet-related disease in disadvantaged communities. Innovative solutions to the 'food desert' problem include the deployment of mobile markets and healthy corner store initiatives. Such initiatives, however, do not always capitalize on the principles guiding retail development and the possibilities of GIS-based data. Simultaneously, community partners are not always engaged effectively in the planning for such interventions, which limits acceptability and suitability of such work. This paper highlights the results of a participatory mapping exercise to optimize the siting of a planned healthy food retail intervention in Flint, Michigan. Potential sites are chosen by engaging experts in a three-stage mapping process that includes the analytic hierarchy process and point allocation of five key variables (including food access, socioeconomic distress, population density, access to transit, and proximity to neighborhood centers), as well as direct mapping of suitable sites. Results suggest a discrete set of areas-primarily in the northwestern quadrant of the city-where small-scale healthy food retail interventions might be most strategically located. Areas with the most consistent overlap between directly mapped sites and very high levels of suitability align well with neighborhoods which are distant from existing grocery stores. As a community-based strategy, this increases the opportunity for effectively improving neighborhood access to healthy foods by optimizing the potential sites for healthy food interventions. Community partners have already been active in using these results in project planning for just such an intervention.

  19. Variationally optimal selection of slow coordinates and reaction coordinates in macromolecular systems

    NASA Astrophysics Data System (ADS)

    Noe, Frank

    To efficiently simulate and generate understanding from simulations of complex macromolecular systems, the concept of slow collective coordinates or reaction coordinates is of fundamental importance. Here we will introduce variational approaches to approximate the slow coordinates and the reaction coordinates between selected end-states given MD simulations of the macromolecular system and a (possibly large) basis set of candidate coordinates. We will then discuss how to select physically intuitive order paremeters that are good surrogates of this variationally optimal result. These result can be used in order to construct Markov state models or other models of the stationary and kinetics properties, in order to parametrize low-dimensional / coarse-grained model of the dynamics. Deutsche Forschungsgemeinschaft, European Research Council.

  20. Making the Optimal Decision in Selecting Protective Clothing

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

    Price, J. Mark

    2008-01-15

    Protective Clothing plays a major role in the decommissioning and operation of nuclear facilities. Literally thousands of 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. This article discusses these factors as well as surveys of plants regarding their level of usage of single use protective clothing and should help individuals making decisions about protective clothing as it appliesmore » to their application. Individuals considering using SUPC should not jump to conclusions. The survey conducted clearly indicates that plants have different drivers. An evaluation should be performed to understand the facility's true drivers for selecting clothing. It is recommended that an interdisciplinary team be formed including representatives from budgets and cost, safety, radwaste, health physics, and key user groups to perform the analysis. The right questions need to be asked and answered by the company providing the clothing to formulate a proper perspective and conclusion. The conclusions and recommendations need to be shared with senior management so that the drivers, expected results, and associated costs are understood and endorsed. In the end, the individual making the recommendation should ask himself/herself: 'Is my decision emotional, or logical and economical?' 'Have I reached the optimal decision for my plant?'.« less