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Computer simulation tools used to predict the energy production of photovoltaic systems are needed in order to make informed economic decisions. These tools require input parameters that characterize module performance under various... more
Computer simulation tools used to predict the energy production of photovoltaic systems are needed in order to make informed economic decisions. These tools require input parameters that characterize module performance under various operational and environmental conditions. Depending upon the complexity of the simulation model, the required input parameters can vary from the limited information found on labels affixed to photovoltaic modules to an extensive set of parameters. The required input parameters are normally obtained indoors using a solar simulator or flash tester, or measured outdoors under natural sunlight. This paper compares measured performance parameters for three photovoltaic modules tested outdoors at the National Institute of Standards and Technology (NIST) and Sandia National Laboratories (SNL). Two of the three modules were custom fabricated using monocrystalline and silicon film cells. The third, a commercially available module, utilized triple-junction amorpho...
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Background: In 2006, an atypical U.S. case of bovine spongiform encephalopathy (BSE) was discovered in Alabama and later reported to be polymorphic for glutamate (E) and lysine (K) codons at position 211 in the bovine prion protein gene... more
Background: In 2006, an atypical U.S. case of bovine spongiform encephalopathy (BSE) was discovered in Alabama and later reported to be polymorphic for glutamate (E) and lysine (K) codons at position 211 in the bovine prion protein gene (Prnp) coding sequence. A bovine E211K mutation is important because it is analogous
The objective of this study was to investigate the ability of image color features to predict subjective pork color scores. Subjective and instrumental color were assessed on the bloomed, cross-sectional surface of pork longissimus... more
The objective of this study was to investigate the ability of image color features to predict subjective pork color scores. Subjective and instrumental color were assessed on the bloomed, cross-sectional surface of pork longissimus thoracis et lumborum chops. Images of pork chop samples were acquired using a computer vision system, and 18 image color features (mean and standard deviation of R, G, B, H, S, I, L*, a*, b*) were extracted for inclusion in partial least squares (PLS) and support vector machine (SVM) regression models. For color scores 2, 3, 4, and 5, the accuracies were 50.4, 75.9, 72.4, and 47.3% classified correctly by PLS, respectively, and 70.7, 72.8, 76.7, and 69.7% by SVM, respectively. The overall prediction accuracies of 2 models for pork color scores were 68.3% for PLS and 73.4% for SVM. There was minimal major misclassification of samples (< 0.5%). Image color features isolated through the development of PLS and SVM models, particularly SVM, show potential a...
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A study was conducted to examine genetic variation in the ham halo condition. The distal portion of the biceps femoris was sampled by taking cores (2.54-cm diameter) from progeny (n = 1,016) from a Duroc meat quality–focused line.... more
A study was conducted to examine genetic variation in the ham halo condition. The distal portion of the biceps femoris was sampled by taking cores (2.54-cm diameter) from progeny (n = 1,016) from a Duroc meat quality–focused line. Commission Internationale de l ́Éclairage (CIE; “International Commission on Illumination”) color-space values (L*, a*, and b*) and myoglobin concentration were measured on the halo (“Halo”) and inside (“Inside”) portion of each core. The Halo portion of the biceps femoris had greater L* and b* and lesser a* and myoglobin content (all P < 0.001) than the Inside portion. Sires with 11 or more progeny were compared. The sire × muscle-location interaction affected (P < 0.001), L*, a*, and myoglobin concentration. Sire progeny groups differed for each trait in both portions of the muscle, but differences in the Halo portion of the muscle were not mirrored in the Inside portion of the muscle. Similarly, sire group affected the magnitude of the difference ...
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This experiment characterized a color defect called halo, involving pale tissue in the superficial portion of ham muscles, causing a two-toned appearance. Biceps femoris muscles (n = 200) were obtained from the ham-boning line of a large... more
This experiment characterized a color defect called halo, involving pale tissue in the superficial portion of ham muscles, causing a two-toned appearance. Biceps femoris muscles (n = 200) were obtained from the ham-boning line of a large processor. Instrumental color attributes were determined on the medial (inside) and lateral (halo) surfaces of the muscle. Muscles were sliced (2.54-cm-thick) perpendicular to the long axis of the muscle. Slices were numbered from the proximal end of the muscle so that slice numbers represented anatomical location. Severity of the defect was greatest on the distal end of the muscle corresponding to slices 6 and 7 (9 locations). The halo and inside portions of slices 6 and 7 were separated for myoglobin concentration and muscle pH determination. The inside portion of muscle had lower (P < 0.001) L* (53.1 versus 63.4) and greater (P < 0.001) a* (23.2 versus 15.3) and b* (18.5 versus 15.4) values than the halo portion. Compared to the halo portio...
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A study was conducted to identify molecular changes reflective of beef tenderness variation and tenderization during postmortem aging. Carcasses (U.S. Select) were selected to represent extremes in tenderness (n = 20; 10 per class). Two... more
A study was conducted to identify molecular changes reflective of beef tenderness variation and tenderization during postmortem aging. Carcasses (U.S. Select) were selected to represent extremes in tenderness (n = 20; 10 per class). Two pairs of adjacent longissimus lumborum steaks from each strip loin were blocked by location and assigned to each aging time (2, 7, 14, or 28 d postmortem). One steak from each pair was designated for slice shear force determination and the other was used for sarcomere length, western blotting for desmin, and non-targeted LC- and GC–MS metabolite profiling. Tough steaks had higher (P < 0.001) slice shear force values than tender steaks, and increasing aging time decreased (P < 0.001) slice shear force values. Tender steaks had a greater (P < 10–4) proportion of desmin degraded than tough steaks, and increasing aging time increased (P < 10–22) desmin degradation in steaks from both classes. From 2,562 profiled metabolites, 102 metabolites w...
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The objective of this study was to enhance estimates of additive, dominance, and epistatic effects of marker polymorphisms on beef carcass and quality traits. Myostatin (MSTN) F94L SNP and the µ-calpain (CAPN1) 316 and 4751 SNP haplotype... more
The objective of this study was to enhance estimates of additive, dominance, and epistatic effects of marker polymorphisms on beef carcass and quality traits. Myostatin (MSTN) F94L SNP and the µ-calpain (CAPN1) 316 and 4751 SNP haplotype have previously been associated with fat and muscle traits in beef cattle. Multiyear selection in a composite population segregating these polymorphisms increased minor allele (F94L L) and chosen haplotype (CAPN1 CC and GT) frequencies to intermediate levels resulting in more precise estimates of additive and non-additive genetic effects. During the 3 yr after selection, 176 steers were evaluated for growth, carcass, meat quality, tenderness (n = 103), and meat color traits. The statistical model included year, age of dam, age of the steer, and genotype in a random animal model. The 9 genotypes (3 CAPN1 diplotypes × 3 F94L genotypes) affected marbling score, ribeye area, adjusted fat thickness, vision yield grade (all P < 0.001), slice shear forc...
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Establishing genomic resources for closely related species will provide comparative insights that are crucial for understanding diversity and variability at multiple levels of biological organization. We developed ESTs for Mexican axolotl... more
Establishing genomic resources for closely related species will provide comparative insights that are crucial for understanding diversity and variability at multiple levels of biological organization. We developed ESTs for Mexican axolotl (Ambystoma mexicanum) and Eastern tiger salamander (A. tigrinum tigrinum), species with deep and diverse research histories. Approximately 40,000 quality cDNA sequences were isolated for these species from various tissues, including regenerating limb and tail. These sequences and an existing set of 16,030 cDNA sequences for A. mexicanum were processed to yield 35,413 and 20,599 high quality ESTs for A. mexicanum and A. t. tigrinum, respectively. Because the A. t. tigrinum ESTs were obtained primarily from a normalized library, an approximately equal number of contigs were obtained for each species, with 21,091 unique contigs identified overall. The 10,592 contigs that showed significant similarity to sequences from the human RefSeq database reflect...
Research Interests: Regeneration, Natural History, Spinal Cord Injury, Gene expression, Biological Sciences, and 14 moreHumans, Expressed Sequence Tags, Animals, Information Transfer, Rats, Model System, Biological Process, Genetic Polymorphism, Zebrafish, Ambystoma, Nucleotide Polymorphism, BMC, Medical and Health Sciences, and Ambystoma mexicanum
Little is known about molecular recognition of acetylated N termini, despite prevalence of this modification among eukaryotic cytosolic proteins. We report that the family of human DCN-like (DCNL) co-E3s, which promote ligation of the... more
Little is known about molecular recognition of acetylated N termini, despite prevalence of this modification among eukaryotic cytosolic proteins. We report that the family of human DCN-like (DCNL) co-E3s, which promote ligation of the ubiquitin-like protein NEDD8 to cullin targets, recognizes acetylated N termini of the E2 enzymes UBC12 and UBE2F. Systematic biochemical and biophysical analyses reveal 40- and 10-fold variations in affinities among different DCNL-cullin and DCNL-E2 complexes, contributing to varying efficiencies of different NEDD8 ligation cascades. Structures of DCNL2 and DCNL3 complexes with N-terminally acetylated peptides from UBC12 and UBE2F illuminate a common mechanism by which DCNL proteins recognize N-terminally acetylated E2s and how selectivity for interactions dependent on N-acetyl-methionine are established through side chains recognizing distal residues. Distinct preferences of UBC12 and UBE2F peptides for inhibiting different DCNLs, including the oncog...
Research Interests: Structure, Kinetics, Biology, Medicine, Macromolecular X-Ray Crystallography, and 12 moreBiological Sciences, Humans, Mice, Animals, CHEMICAL SCIENCES, Protein Secondary Structure Prediction, Substrate Specificity, Acetylation, Amino Acid Sequence, Cell Cycle Proteins, Protein Binding, and Molecular Sequence Data
In the meat industry, a "high event period" (HEP) is defined as a time period during which commercial meat plants experience a higher than usual rate of Escherichia coli O157:H7 contamination. Genetic analysis indicated that... more
In the meat industry, a "high event period" (HEP) is defined as a time period during which commercial meat plants experience a higher than usual rate of Escherichia coli O157:H7 contamination. Genetic analysis indicated that within a HEP, most of the E. coli O157:H7 strains belong to a singular dominant strain type. This was in disagreement with the current beef contamination model stating that contamination occurs when incoming pathogen load on animal hides, which consists of diverse strain types of E. coli O157:H7, exceeds…
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Short tandem repeat (STR) DNA typing is a global standard for human identification. Current practice involves highly trained forensic analysts, operating in a laboratory setting, using multiple instruments to process samples and analyze... more
Short tandem repeat (STR) DNA typing is a global standard for human identification. Current practice involves highly trained forensic analysts, operating in a laboratory setting, using multiple instruments to process samples and analyze the data. Here, we report the developmental validation of a fully integrated and automated DNA profiling system, the RapidHIT(®) System, capable of producing up to five high quality STR profiles with full controls in approximately 90min using PowerPlex(®)16 HS RapidHIT chemistry. The system integrates all sample handling steps: starting from lysis of cells on buccal swabs or other buccal sample types through DNA extraction, normalization, amplification,capillary array electrophoresis, detection, and integrated software analysis. The results describe the developmental validation of the RapidHIT™ System for buccal samples processed with the DNA IQ™ extraction chemistry using a guandinium chaotropic agent and paramagnetic beads followed by amplification...
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Actin related protein 2/actin related protein 3 (Arp2/3) complex nucleates new actin filaments in eukaryotic cells in response to signals from proteins in the Wiskott–Aldrich syndrome protein (WASP) family. The conserved VCA domain of... more
Actin related protein 2/actin related protein 3 (Arp2/3) complex nucleates new actin filaments in eukaryotic cells in response to signals from proteins in the Wiskott–Aldrich syndrome protein (WASP) family. The conserved VCA domain of WASP proteins activates Arp2/3 complex by inducing conformational changes and delivering the first actin monomer of the daughter filament. Previous models of activation have invoked a single VCA acting at a single site on Arp2/3 complex. Here we show that activation most likely involves engagement of two distinct sites on Arp2/3 complex by two VCA molecules, each delivering an actin monomer. One site is on Arp3 and the second is on ARPC1 and Arp2. The VCAs at these sites have distinct roles in activation. Our findings reconcile apparently conflicting literature on VCA activation of Arp2/3 complex and lead to a new model for this process.
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Research Interests: Evolutionary Biology, Genetics, Stochastic Process, Molecular Evolution, Biology, and 15 moreMitochondria, Medicine, Sequence Analysis, Mitochondrial DNA, Maximum Likelihood, Birds, Animals, Protein structure, Distance Estimation, Evolutionary rate, Cytochrome B, Amino Acid Sequence, Biochemistry and cell biology, DNA sequence, and Nucleotide substitution
Herpes simplex virus type 1 (HSV-1) enters cells by fusion of its envelope with a host cell membrane, which requires four viral glycoproteins and a cellular receptor. Viral fusion glycoprotein B (gB) mediates membrane fusion through the... more
Herpes simplex virus type 1 (HSV-1) enters cells by fusion of its envelope with a host cell membrane, which requires four viral glycoproteins and a cellular receptor. Viral fusion glycoprotein B (gB) mediates membrane fusion through the action of its ectodomain, while its cytoplasmic domain (cytodomain) regulates fusion from the opposite face of the membrane by an unknown mechanism. The gB cytodomain appears to restrict fusion, because point or truncation mutations within it increase the extent of fusion ( syn mutations). Previously, we showed that the hyperfusion phenotype correlated with reduced membrane binding in gB syn truncation mutants and proposed that membrane binding was important in regulating fusion. Here, we extended our analysis to three syn point mutants: A855V, R858H, and A874P. These mutations produce local conformational changes, with some affecting membrane interaction, which suggests that while syn mutants may deregulate fusion by somewhat different mechanisms, m...
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The transcription factor GATA1 regulates an extensive program of gene activation and repression during erythroid development. However, the associated mechanisms, including the contributions of distal versus proximal cis-regulatory... more
The transcription factor GATA1 regulates an extensive program of gene activation and repression during erythroid development. However, the associated mechanisms, including the contributions of distal versus proximal cis-regulatory modules, co-occupancy with other transcription factors, and the effects of histone modifications, are poorly understood. We studied these problems genome-wide in a Gata1 knockout erythroblast cell line that undergoes GATA1-dependent terminal maturation, identifying 2616 GATA1-responsive genes and 15,360 GATA1-occupied DNA segments after restoration of GATA1. Virtually all occupied DNA segments have high levels of H3K4 monomethylation and low levels of H3K27me3 around the canonical GATA binding motif, regardless of whether the nearby gene is induced or repressed. Induced genes tend to be bound by GATA1 close to the transcription start site (most frequently in the first intron), have multiple GATA1-occupied segments that are also bound by TAL1, and show evol...
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Identification of functional genomic regions using interspecies comparison will be most effective when the full span of relationships between genomic function and evolutionary constraint are utilized. We find that sets of putative... more
Identification of functional genomic regions using interspecies comparison will be most effective when the full span of relationships between genomic function and evolutionary constraint are utilized. We find that sets of putative transcriptional regulatory sequences, defined by ENCODE experimental data, have a wide span of evolutionary histories, ranging from stringent constraint shown by deep phylogenetic comparisons to recent selection on lineage-specific elements. This diversity of evolutionary histories can be captured, at least in part, by the suite of available comparative genomics tools, especially after correction for regional differences in the neutral substitution rate. Putative transcriptional regulatory regions show alignability in different clades, and the genes associated with them are enriched for distinct functions. Some of the putative regulatory regions show evidence for recent selection, including a primate-specific, distal promoter that may play a novel role in ...
Research Interests: Genomics, Molecular Evolution, Comparative Genomics, Biology, Medicine, and 12 moreFunctional Genomics, Biological Sciences, Primates, Humans, Animals, Evolutionary History, Genome, Evolutionary Constraint, Experimental Data, Gene Expression Regulation, Regional Difference, and Medical and Health Sciences
Genomic sequence signals—such as base composition, presence of particular motifs, or evolutionary constraint—have been used effectively to identify functional elements. However, approaches based only on specific signals known to correlate... more
Genomic sequence signals—such as base composition, presence of particular motifs, or evolutionary constraint—have been used effectively to identify functional elements. However, approaches based only on specific signals known to correlate with function can be quite limiting. When training data are available, application of computational learning algorithms to multispecies alignments has the potential to capture broader and more informative sequence and evolutionary patterns that better characterize a class of elements. However, effective exploitation of patterns in multispecies alignments is impeded by the vast number of possible alignment columns and by a limited understanding of which particular strings of columns may characterize a given class. We have developed a computational method, called ESPERR (evolutionary and sequence pattern extraction through reduced representations), which uses training examples to learn encodings of multispecies alignments into reduced forms tailored ...
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Research Interests: Microbiology, Polymorphism, Biology, Medicine, Bayesian Analysis, and 15 moreGlutamate, Haplotypes, Female, Animals, Male, Cattle, Prevalence, Bovine Spongiform Encephalopathy, Genetic variation, Codon, Allele Frequency, Biochemistry and cell biology, Posterior distribution, Autosomal Dominant, and Gene frequency
ABSTRACT Density functional theory (DFT) calculations are conducted to explore the interaction of H2 with pure and Ti-doped WO3 (002) surfaces. Four top adsorption models of H2 on pure and Ti-doped WO3 (002) surfaces are investigated... more
ABSTRACT Density functional theory (DFT) calculations are conducted to explore the interaction of H2 with pure and Ti-doped WO3 (002) surfaces. Four top adsorption models of H2 on pure and Ti-doped WO3 (002) surfaces are investigated respectively, they are adsorption on bridging oxygen O1c, absorption on plane oxygen O2c, absorption on 5-fold W5c (Ti), and absorption on 6-fold W6c. The most stable and H2 possible adsorption structure in the pure surface is H-end oriented to the surface plane oxygen O2c site, while the favourable adsorption sites for H2 in a Ti-doped surface is not only an O2c site but also a W6c site. The adsorption energy, the Fermi energy level EF, and the electronic population are investigated and the H2-sensing mechanism of a pure-doped WO3 (002) surface is revealed theoretically: the theoretical results are in good accordance with our existing experimental results. By comparing the above three terms, it is found that Ti doping can obviously enhance the adsorption of H2. It can be predicted that the method of Ti-doped into a WO3 thin film is an effective way to improve WO3 sensor sensitivity to H2 gas.
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Tissue development and function are exquisitely dependent on proper regulation of gene expression, but it remains controversial whether the genomic signals controlling this process are subject to strong selective constraint. While some... more
Tissue development and function are exquisitely dependent on proper regulation of gene expression, but it remains controversial whether the genomic signals controlling this process are subject to strong selective constraint. While some studies show that highly constrained noncoding regions act to enhance transcription, other studies show that DNA segments with biochemical signatures of regulatory regions, such as occupancy by a transcription factor, are seemingly unconstrained across mammalian evolution. To test the possible correlation of selective constraint with enhancer activity, we used chromatin immunoprecipitation as an approach unbiased by either evolutionary constraint or prior knowledge of regulatory activity to identify DNA segments within a 66-Mb region of mouse chromosome 7 that are occupied by the erythroid transcription factor GATA1. DNA segments bound by GATA1 were identified by hybridization to high-density tiling arrays, validated by quantitative PCR, and tested fo...
Research Interests: Gene regulation, Molecular Evolution, Gene expression, Biological Sciences, DNA, and 15 morePhylogeny, Mice, Animals, Prior Knowledge, Genome, Chip, Chromatin Immunoprecipitation, Evolutionary Constraint, High Density Concrete, Amino Acid Sequence, Binding Site, Gene Expression Regulation, binding sites, High density, and Medical and Health Sciences
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Research Interests: Functional Analysis, Biology, Medicine, Gene expression, Mammals, and 15 moreBiological Sciences, Humans, Mice, Animals, Genome, Chromatin Immunoprecipitation, Multiple Sequence Alignment, Genome sequence, Experimental Validation, Amino Acid Sequence, Binding Site, Gene expression profiling, binding sites, Multiple alignment, and Medical and Health Sciences
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We estimate a model of House... more
We estimate a model of House members&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; roll call voting decisions embodying some hypotheses about representation, including estimates of the influence of district opinion on broad collective issues relative to personal economic interests, of the effect of electoral security on constituency responsiveness, and of the difference in constituency and party voting among Republicans and Democrats. This model is estimated with votes taken during deliberations on the 1978 Tax Reform Act, important because it was a significant change from the tax reforms passed in the late 1960s and 1970s, marked the first appearance of the Kemp-Roth proposed tax cut, and represented a concerted effort by Republicans to make tax policy a broad national issue. Findings indicate that constituent preferences for redistribution are important influences on…
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Origin and Activity of Oxidized Gold in Water-Gas-Shift Catalysis. Zhi-Pan Liu, Stephen J. Jenkins, and David A. King Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom. Received 26 January... more
Origin and Activity of Oxidized Gold in Water-Gas-Shift Catalysis. Zhi-Pan Liu, Stephen J. Jenkins, and David A. King Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom. Received 26 January 2005; published 19 May 2005 ...
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Optimal allocation strategies are calculated for annual plants in fluctuating environments using a two-component model of plant growth, in which photosynthate is partitioned between a vegetative and a reproductive component. Previous... more
Optimal allocation strategies are calculated for annual plants in fluctuating environments using a two-component model of plant growth, in which photosynthate is partitioned between a vegetative and a reproductive component. Previous studies have shown that final reproductive yield ...
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Four conditioned suppression experiments examined the influence of contextual stimuli on the rat&amp;amp;#39;s fear of an extinguished conditioned stimulus (CS). When rats received pairings of a CS with shock in one context and then... more
Four conditioned suppression experiments examined the influence of contextual stimuli on the rat&amp;amp;#39;s fear of an extinguished conditioned stimulus (CS). When rats received pairings of a CS with shock in one context and then extinction of the CS in another context, fear of the CS was renewed when the CS was returned to and tested in the original context (Experiments 1 and 3). No such renewal was obtained when the CS was tested in a second context after extinction had occurred in the conditioning context (Experiment 4). In Experiment 2, shocks presented following extinction reinstated fear of the CS, but only if they were presented in the context in which the CS was tested. In each experiment, the associative properties of the contexts were independently assessed. Contextual excitation was assessed primarily with context-preference tests in which the rats chose to sit in either the target context or an adjoining side compartment. Contextual inhibition was assessed with summation tests. Although reinstatement was correlated with demonstrable contextual excitation present during testing, the renewal effect was not. Moreover, there was no evidence that contextual inhibition developed during extinction. The results suggest that fear of an extinguished CS can be affected by the excitatory strength of the context but that independently demonstrable contextual excitation or inhibition is not necessary for contexts to control that fear.
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To help inform discussion of the educational value of community service, we report results of an experiment in integrating service-learning into a large undergraduate political science course. Students in service-learning sections of the... more
To help inform discussion of the educational value of community service, we report results of an experiment in integrating service-learning into a large undergraduate political science course. Students in service-learning sections of the course were significantly more likely than those in the traditional discussion sections to report that they had performed up to their potential in the course, had learned to apply principles from the course to new situations, and had developed a greater awareness of societal problems. Classroom learning and course grades also increased significantly as a result of students’ participation in course-relevant community service. Finally, pre- and postsurvey data revealed significant effects of participation in community service upon students’ personal values and orientations. The experiential learning acquired through service appears to compensate for some pedagogical weaknesses of classroom instruction.
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Page 1. David A. King The ability to judge a nation's scientific standing is vital for the governments, busi-nesses and trusts that must decide scientific priorities and funding. In this paper I analyse the output and outcomes from ...
Research Interests: Biochemistry, Bioinformatics, Environmental Science, Developmental Biology, Climate Change, and 15 moreBibliometrics, Computational Biology, Biotechnology, Cancer, Biology, Cell Cycle, Ecology, Drug Discovery, Evolution, Astrophysics, Astronomy, Biological Sciences, DNA, Cell Signalling, and Earth Science
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Purpose: Aortic blebs—focal outpouchings within aortic aneurysms—may contribute to their eventual rupture. In this study we determine the incidence of aortic blebs and describe their microscopic features. Methods: Computed tomographic... more
Purpose: Aortic blebs—focal outpouchings within aortic aneurysms—may contribute to their eventual rupture. In this study we determine the incidence of aortic blebs and describe their microscopic features. Methods: Computed tomographic scans of the abdominal aorta were obtained in 188 patients with aortic diameters measuring≥ 3 cm and were independently evaluated by a radiologist. The number and location of blebs were recorded, and each was measured with calipers. Sixteen blebs, with an adjacent uninvolved aneurysmal segment ...
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Comas-Herrera, Adelina and King, Derek and Malley, Juliette and Pickard, Linda and Wittenberg, Raphael and Darton, R (2006) Thirty-five years on: future demands for long-term care in England. PSSRU Research Summary 35. London School of... more
Comas-Herrera, Adelina and King, Derek and Malley, Juliette and Pickard, Linda and Wittenberg, Raphael and Darton, R (2006) Thirty-five years on: future demands for long-term care in England. PSSRU Research Summary 35. London School of Economcis and ...
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A susceptibility gene for Wilms' tumour (WT), designated FWT1, was previously mapped to chromosome 17q12–q21 by linkage analysis of a single family. We now confirm the existence of this gene by analysis of additional cases in the... more
A susceptibility gene for Wilms' tumour (WT), designated FWT1, was previously mapped to chromosome 17q12–q21 by linkage analysis of a single family. We now confirm the existence of this gene by analysis of additional cases in the original family (3-point LOD ...
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Superconducting gap anisotropy at least an order of magnitude larger than that of the conventional superconductors has been observed in the ab plane of Bi2Sr2CaCu2O(8+delta) in angle-resolved photoemission spectroscopy. For samples with... more
Superconducting gap anisotropy at least an order of magnitude larger than that of the conventional superconductors has been observed in the ab plane of Bi2Sr2CaCu2O(8+delta) in angle-resolved photoemission spectroscopy. For samples with Tc of 88 K, the gap size reaches a ...
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EDITED BY JOSEPH S. NYE, JR. PHILIP D. ZELIKOW DAVID C. KING WHY DON'T TRUST GOVERNMENT II Ik CSS .M.*-^*. ' wi ... Why People Don't Trust Government This One 7AGH-KRO-5SYX ... Copyright © 1997 by the President and Fellows... more
EDITED BY JOSEPH S. NYE, JR. PHILIP D. ZELIKOW DAVID C. KING WHY DON'T TRUST GOVERNMENT II Ik CSS .M.*-^*. ' wi ... Why People Don't Trust Government This One 7AGH-KRO-5SYX ... Copyright © 1997 by the President and Fellows of Harvard College All rights reserved Printed in the ...
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This article describes a set of alignments of 28 vertebrate genome sequences that is provided by the UCSC Genome Browser. The alignments can be viewed on the Human Genome Browser (March 2006 assembly) at http://genome. ucsc. edu,... more
This article describes a set of alignments of 28 vertebrate genome sequences that is provided by the UCSC Genome Browser. The alignments can be viewed on the Human Genome Browser (March 2006 assembly) at http://genome. ucsc. edu, downloaded in bulk by anonymous FTP from http://hgdownload. cse. ucsc. edu/goldenPath/hg18/multiz28way, or analyzed with the Galaxy server at http://g2. bx. psu. edu. This article illustrates the power of this resource for exploring vertebrate and mammalian evolution, using three examples. ...