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Selected AbstractsEffect of Point-of-care Influenza Testing on Management of Febrile ChildrenACADEMIC EMERGENCY MEDICINE, Issue 12 2006Srikant B. Iyer MD Abstract Objectives To determine the effect of point-of-care testing (POCT) for influenza on the physician management of febrile children who are at risk for serious bacterial illness (SBI) on the basis of age and temperature and who are presenting to a pediatric emergency department (ED) during an influenza outbreak. Methods Patients 2,3 months of age with temperature of ,38°C and patients 3,24 months of age with temperature of ,39°C who were presenting to a pediatric ED during an influenza outbreak were enrolled into a prospective, quasi-randomized, controlled trial. Influenza testing was performed on enrolled patients by either the POCT or the standard-testing (ST) methods. The two groups were compared in terms of laboratory testing, chest radiography, antibiotic use, visit-associated costs, pediatric ED lengths of stay, inpatient admission, and return visits to the pediatric ED. Similar analyses also were performed on the resulting subgroups of patients on the basis of method of testing (POCT or ST) and test result (positive or negative). Results Of 767 eligible patients, 700 (91%) completed the study. No significant differences were demonstrated between the POCT and ST groups with respect to laboratory tests ordered, chest radiographs obtained, antibiotic administration, inpatient admission, return visits to the pediatric ED, lengths of stay, or visit-associated costs. In the subgroup analysis, the adjusted odds ratios (ORs) for blood culture in influenza test,positive to ,negative patients were 0.59 and 0.71 in the POCT and ST groups, respectively (p = 0.088). The adjusted ORs for urine culture in influenza test,positive to ,negative patients were 0.46 and 0.67 in the POCT and ST groups, respectively (p = 0.005). Conclusions When using a strategy of performing influenza testing on all patients at risk for SBI who presented to a pediatric ED during an influenza outbreak, the method of testing (POCT or ST) did not appear to significantly alter physician management, cost, or length of stay in the pediatric ED. However, if the interaction of the method of testing and the test result (positive or negative) were considered, a positive POCT for influenza was associated with a significant reduction in orders for urinalyses and urine cultures. [source] ORIGINAL ARTICLE: Big dams and salmon evolution: changes in thermal regimes and their potential evolutionary consequencesEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 2 2008Michael J. Angilletta Jr Abstract Dams designed for hydropower and other purposes alter the environments of many economically important fishes, including Chinook salmon (Oncorhynchus tshawytscha). We estimated that dams on the Rogue River, the Willamette River, the Cowlitz River, and Fall Creek decreased water temperatures during summer and increased water temperatures during fall and winter. These thermal changes undoubtedly impact the behavior, physiology, and life histories of Chinook salmon. For example, relatively high temperatures during the fall and winter should speed growth and development, leading to early emergence of fry. Evolutionary theory provides tools to predict selective pressures and genetic responses caused by this environmental warming. Here, we illustrate this point by conducting a sensitivity analysis of the fitness consequences of thermal changes caused by dams, mediated by the thermal sensitivity of embryonic development. Based on our model, we predict Chinook salmon likely suffered a decrease in mean fitness after the construction of a dam in the Rogue River. Nevertheless, these demographic impacts might have resulted in strong selection for compensatory strategies, such as delayed spawning by adults or slowed development by embryos. Because the thermal effects of dams vary throughout the year, we predict dams impacted late spawners more than early spawners. Similar analyses could shed light on the evolutionary consequences of other environmental perturbations and their interactions. [source] Solid-phase aroma concentrate extraction (SPACEÔ ): a new headspace technique for more sensitive analysis of volatilesFLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2004Masashi Ishikawa Abstract The SPACEÔ (solid-phase aroma concentrate extraction) method is a modi,ed version of the SPME (solid-phase micro extraction) technique for headspace analysis, with increased area of the adsorbent to enable more sensitive analysis of volatiles. The SPACEÔ rod used in the technique is fabricated from stainless steel coated with an adsorbent mixture, consisting mainly of a graphite carbon. Initially, the SPACEÔ rod is ,xed in the head of a closed ,ask, where it adsorbs the aroma. Next, the rod is thermally desorbed on-line with a high-resolution gas chromatography,mass spectrometer (HRGC,MS). In the present experiments, SPACEÔ sampling reproducibility was determined by analysing a standard mixture and roasted coffee beans. The SPACEÔ rod collected the analytes with good reproducibility, with the exception of high polar compounds. Similar analyses of coffee powder were performed by SPME and other methods for comparison with the SPACEÔ method. The SPACEÔ method proved to have superior capabilities with high concentrations, and it produced a well-balanced chromatogram. Copyright © 2004 John Wiley & Sons, Ltd. [source] Differing Patterns of Antiresorptive Pharmacotherapy in Nursing Facility Residents and Community DwellersJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 8 2005Carolyn M. Jachna MD Objectives: Little is known about differences between current patterns of antiresorptive therapy (ART) use in nursing facility (NF) residents and by community-dwelling older adults (CDs). ART use was compared in older NF residents and CDs. Design: Cross-sectional analysis. Setting: Kansas Medicaid files from May 2000 through April 2001. Participants: Women aged 65 and older having at least 9 months of data as a CD or NF resident. Measurements: Pharmacy claims were used to identify any ART prescription, including hormone replacement therapy (HRT), a bisphosphonate, raloxifene, or calcitonin. Demographic and clinical variables were identified from the claims files. Factors associated with ART use in bivariate analyses were entered into logistic regression models. Similar analyses were performed for bisphosphonate use among non-estrogen replacement therapy (non-ERT) ARTs (excluding HRT). Results: The final study sample (N=2,289) included 898 NF (mean age 85.2) residents and 1,391 CDs (mean age 76.6). CDs were more likely to receive any ART (24.5%) than NF residents (19.6%). After adjustment for potential confounders, NF residents aged 65 to 84 were less likely (odds ratio (OR)=0.61, 95% confidence interval (CI)=0.44,0.85) to receive ART than CDs of the same age. Conversely, of those aged 85 and older, NF residents were more likely than CDs to receive ART (OR=1.96, 95% CI=1.18,3.25). Calcitonin was the most common non-ERT ART prescribed for NF residents, whereas bisphosphonates were more often prescribed for CDs. Conclusion: Underusage of ART is common in NF and CD cohorts. NF residents are less likely to receive bisphosphonates and more likely to receive calcitonin, for which efficacy is less clear. Further research is needed to identify factors influencing ART prescribing and selection of specific ARTs in different settings. [source] Multiple vitellogenin-derived yolk proteins in gray mullet (Mugil cephalus): Disparate proteolytic patterns associated with ovarian follicle maturationMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 8 2008Haruna Amano PhD Abstract Disparate proteolytic patterns of yolk proteins, derived from three types of vitellogenin (VgA, VgB, and VgC), were observed in gray mullet. Immuno-biochemical analyses of extracts obtained from vitellogenic ovaries (VO) and ovulated eggs (OE) confirmed that a large proportion of VgA-derived lipovitellin (LvA) was degraded into free amino acids (FAAs) during ovarian follicle maturation. The maturation-associated alteration of VgB-derived Lv (LvB) involved only limited proteolysis; the heavy and light LvB chains were dissociated into at least three and one polypeptide fragments, respectively. The native mass of VgC-derived Lv (LvC) exhibited little difference between VO and OE, although it was apparent that the LvC was ,nicked' during maturation, resulting in the appearance of several bands in OE. Similar analyses confirmed that VgA-derived ,,-component (,,-cA) and VgB-derived ,,-c (,,-cB) decreased during maturation in both quantity and native mass, while phosvitin derived from either VgA (PvA) or VgB (PvB) appeared to be degraded into FAAs. The pattern of maturation-associated proteolysis of mullet yolk proteins is similar to that reported for other marine teleosts spawning pelagic eggs. However, the depository ratio of the three distinct types of Lv in the mullet VO appeared to be different from that estimated for another marine pelagophil, the barfin flounder. These results support a recent paradigm regarding the significance of Vg multiplicity upon successive physiological events in this group of fishes including the hydration of maturing oocytes, the acquisition of proper egg buoyancy, and the generation of requisite nutrient stocks for each stage of embryogenesis and larval development. Mol. Reprod. Dev. 75: 1307,1317, 2008. © 2008 Wiley-Liss, Inc. [source] Plasticity of Cadherin,Catenin Expression in the Melanocyte LineagePIGMENT CELL & MELANOMA RESEARCH, Issue 4 2000ALICE JOUNEAU Cadherins are calcium-dependent cell adhesion receptors with strong morphoregulatory functions. To mediate functional adhesion, cadherins must interact with actin cytoskeleton. Catenins are cytoplasmic proteins that mediate the interactions between cadherins and the cytoskeleton. In addition to their role in cell,cell adhesion, catenins also participate in signaling pathways that regulate cell growth and differentiation. Cadherins and catenins appear to be involved in melanocyte development and transformation. Here, we investigated the function of cadherin,catenin complexes in the normal development and transformation of melanocytes by studying the patterns of expression of the cell,cell adhesion molecules, E-, N- and P-cadherin, and the expression of their cytoplasmic partners, ,-, ,- and ,-catenin, during murine development. Similar analyses were performed in vitro using murine melanoblast, melanocyte, and melanoma cell lines in the presence and absence of keratinocytes, the cells with which melanocytes interact in vivo. Overall, the results suggest that the expression of cadherins and catenins is very plastic and depends on their environment as well as the transformation status of the cells. This plasticity is important in fundamental cellular mechanisms associated with normal and pathological ontogenesis, as well as with tumorigenesis. [source] Characterization of a new xyloglucan endotransglucosylase/hydrolase (XTH) from ripening tomato fruit and implications for the diverse modes of enzymic actionTHE PLANT JOURNAL, Issue 2 2006Montserrat Saladié Summary Xyloglucan endotransglucosylase/hydrolases (XTHs) are cell wall-modifying enzymes that align within three or four distinct phylogenetic subgroups. One explanation for this grouping is association with different enzymic modes of action, as XTHs can have xyloglucan endotransglucosylase (XET) or endohydrolase (XEH) activities. While Group 1 and 2 XTHs predominantly exhibit XET activity, to date the activity of only one member of Group 3 has been reported: nasturtium TmXH1, which has a highly specialized function and hydrolyses seed-storage xyloglucan rather than modifying cell wall structure. Tomato fruit ripening was selected as a model to test the hypothesis that preferential XEH activity might be a defining characteristic of Group 3 XTHs, which would be expressed during processes where net xyloglucan depolymerization occurs. Database searches identified 25 tomato XTHs, and one gene (SlXTH5) was of particular interest as it aligned within Group 3 and was expressed abundantly during ripening. Recombinant SlXTH5 protein acted primarily as a transglucosylase in vitro and depolymerized xyloglucan more rapidly in the presence than in the absence of xyloglucan oligosaccharides (XGOs), indicative of XET activity. Thus, there is no correlation between the XTH phylogenetic grouping and the preferential enzymic activities (XET or XEH) of the proteins in those groups. Similar analyses of SlXTH2, a Group 2 tomato XTH, and nasturtium seed TmXTH1 revealed a spectrum of modes of action, suggesting that all XTHs have the capacity to function in both modes. The biomechanical properties of plant walls were unaffected by incubation with SlXTH5, with or without XGOs, suggesting that XTHs do not represent primary cell wall-loosening agents. The possible roles of SlXTH5 in vivo are discussed. [source] Global transcript profiling of primary stems from Arabidopsis thaliana identifies candidate genes for missing links in lignin biosynthesis and transcriptional regulators of fiber differentiationTHE PLANT JOURNAL, Issue 5 2005Jürgen Ehlting Summary Different stages of vascular and interfascicular fiber differentiation can be identified along the axis of bolting stems in Arabidopsis. To gain insights into the metabolic, developmental, and regulatory events that control this pattern, we applied global transcript profiling employing an Arabidopsis full-genome longmer microarray. More than 5000 genes were differentially expressed, among which more than 3000 changed more than twofold, and were placed into eight expression clusters based on polynomial regression models. Within these, 182 upregulated transcription factors represent candidate regulators of fiber development. A subset of these candidates has been associated with fiber development and/or secondary wall formation and lignification in the literature, making them targets for functional studies and comparative genomic analyses with woody plants. Analysis of differentially expressed phenylpropanoid genes identified a set known to be involved in lignin biosynthesis. These were used to anchor co-expression analyses that allowed us to identify candidate genes encoding proteins involved in monolignol transport and monolignol dehydrogenation and polymerization. Similar analyses revealed candidate genes encoding enzymes that catalyze missing links in the shikimate pathway, namely arogenate dehydrogenase and prephenate aminotransferase. [source] Radiofrequency Neurotomy for Low Back Pain: Evidence-Based Procedural GuidelinesPAIN MEDICINE, Issue 2 2005W. Michael Hooten MD ABSTRACT Objective., This review was undertaken to outline the procedural limitations of the randomized controlled trials (RCTs) of radiofrequency (RF) neurotomy for low back pain. Second, the literature related to patient selection, diagnostic testing, and the technique of performing lumbar spine, RF neurotomy will be critically reviewed and analyzed. Based on these analyses, diagnostic and procedural guidelines will be proposed. Design., A Medline and EMBASE search identified three RCTs and two systematic reviews of RF neurotomy for low back pain. A similar search identified pertinent literature related to the method of patient selection for a diagnostic block, the medial branch and L5 dorsal ramus comparative block, and the anatomical and technical parameters of lumbar spine RF neurotomy. Results., Substantial procedural shortcomings were identified in all three RCTs. In the systematic reviews, these procedural limitations were not accounted for by the quality assessment of study design which resulted in an inaccurate estimate of clinical effectiveness. Analysis using likelihood ratios showed that screening criteria could increase the probability of zygapophysial joint pain before performing diagnostic blocks. Similar analysis showed that comparative medial branch blocks, rather than single blocks, must be used before RF neurotomy. Anatomical studies demonstrated that the shorter distal compared with the circumferential radius of the RF lesion necessitates placement of the electrode parallel to the course of the nerve along the base of the superior articular process. Conclusions., The evidence-based procedural guidelines provide consistent criteria for multisite studies that could enroll a sufficiently large homogenous study cohort. [source] Native Fluorescence Spectroscopy of Blood Plasma in the Characterization of Oral Malignancy,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 2 2003S. Madhuri ABSTRACT Native fluorescence characteristics of blood plasma were studied in the visible spectral region, at two different excitation wavelengths, 405 and 420 nm, to discriminate patients with different stages of oral malignancy from healthy subjects. The fluorescence spectra of blood plasma of oral malignant subjects exhibit characteristic spectral differences with respect to normal subjects. Different ratios were calculated using the fluorescence intensity values at those emission wavelengths that give characteristic spectral features of each group of experimental subjects studied. These fluorescence intensity ratios were used as input variables for a multiple linear discriminant analysis across different groups. Leave-one out cross-validation was used to check the reliability of each discriminant analysis performed. The discriminant analysis performed across normal and oral cancerous subjects classified 94.7% of the original grouped cases and 93.7% of the cross-validated grouped cases. A classification algorithm was developed on the basis of the score of the discriminant functions (discriminant score) resulted in the analyses. The diagnostic potentiality of the present technique was also estimated in the discrimination of malignant subjects from normal and nonmalignant diseased subjects such as liver diseases. In the discriminant analysis performed across the three groups, normal, oral malignancy (including early and advanced stages) and liver diseases, 99% of the original grouped cases and 95.9% of the cross-validated grouped cases were correctly classified. Similar analysis performed across normal, early stage of oral malignancy, advanced oral malignancy and liver diseases correctly classified 94.9% of the original grouped cases and 91.8% of the cross-validated grouped cases. [source] Phylogenetic analyses of ribosomal DNA-containing bacterioplankton genome fragments from a 4000 m vertical profile in the North Pacific Subtropical GyreENVIRONMENTAL MICROBIOLOGY, Issue 9 2008Vinh D. Pham Summary High-throughput identification of rRNA gene-containing clones in large insert metagenomic libraries is difficult, because of the high background of host ribosomal RNA (rRNA) and rRNA genes. To address this challenge, a membrane hybridization method was developed to identify all bacterial small subunit rRNA-containing fosmid clones of microbial community DNA from seven different depths in the North Pacific Subtropical Gyre. Out of 101,376 clones screened, 751 rDNA-containing clones were identified that grouped in ,60 different clades. Several rare sequences only remotely related to known groups were detected, including a Wolbachia -related sequence containing a putative intron or intervening sequence, as well as seven sequences from Order Myxococcales not previously detected in pelagic habitats. Stratified, depth-specific population structure was evident within both cultured and uncultured lineages. Conversely, some eurybathyal members of the genera Alcanivorax and Rhizobium shared identical small subunit ribosomal DNA sequences that were distributed from surface waters to the 4000 m depth. Comparison with similar analyses in Monterey Bay microbial communities revealed previously recognized, as well as some distinctive, depth-stratified partitioning that distinguished coastal from open ocean bacterioplankton populations. While some bias was evident in fosmid clone recovery in a few particular lineages, the overall phylogenetic group recovery and distributions were consistent with previous studies, as well as with direct shotgun sequence data from the same source DNA. [source] INDEPENDENT EVOLUTION OF COMPLEX LIFE HISTORY ADAPTATIONS IN TWO FAMILIES OF FISHES, LIVE-BEARING HALFBEAKS (ZENARCHOPTERIDAE, BELONIFORMES) AND POECILIIDAE (CYPRINODONTIFORMES)EVOLUTION, Issue 11 2007David Reznick We have previously documented multiple, independent origins of placentas in the fish family Poeciliidae. Here we summarize similar analyses of fishes in the family Zenarchopteridae. This family includes three live-bearing genera. Earlier studies documented the presence of superfetation, or the ability to carry multiple litters of young in different stages of development in the same ovary, in some species in all three genera. There is also one earlier report of matrotrophy, or extensive postfertilization maternal provisioning, in two of these genera. We present detailed life-history data for approximately half of the species in all three genera and combine them with the best available phylogeny to make inferences about the pattern of life-history evolution within this family. Three species of Hemirhamphodon have superfetation but lack matrotrophy. Most species in Nomorhamphus and Dermogenys either lack superfetation and matrotrophy or have both superfetation and matrotrophy. Our phylogenetic analysis shows that matrotrophy may have evolved independently in each genus. In Dermogenys, matrotrophic species produce fewer, larger offspring than nonmatrotrophic species. In Nomorhamphus; matrotrophic species instead produce more and smaller offspring than lecithotrophic species. However, the matrotrophic species in both genera have significantly smaller masses of reproductive tissue relative to their body sizes. All aspects of these results are duplicated in the fish family Poeciliidae. We discuss the possible adaptive significance of matrotrophy in the light of these new results. The two families together present a remarkable opportunity to study the evolution of a complex trait because they contain multiple, independent origins of the trait that often include close relatives that vary in either the presence or absence of the matrotrophy or in the degree to which matrotrophy is developed. These are the raw materials that are required for either an analysis of the adaptive significance of the trait or for studies of the genetic mechanisms that underlie the evolution of the trait. [source] Modification of growing-season surface temperature records in the northern great plains due to land-use transformation: verification of modelling results and implication for global climate changeINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 3 2004Rezaul Mahmood Abstract Land-use and land-cover change can modify near-surface atmospheric condition. Mesoscale modelling studies have shown that modification in land use affects near-surface soil moisture storage and energy balance. Such a study in the Great Plains showed that changes in land use from natural grass to irrigated agriculture enhanced soil water storage in the root zone and increased latent energy flux. This increase in latent energy flux would correspond to a decrease in sensible heat flux and, therefore, modify near-surface temperature records. To verify this deduction, we have investigated the changes in the historical near-surface temperature records in Nebraska, USA. We have analysed the long-term mean monthly maximum, minimum, and monthly mean air temperature data from five irrigated and five non-irrigated sites. The cooperative weather observation (coop) network is the source of the data. We have found that there is a clear trend in decreasing mean maximum and average temperature data for irrigated sites. For example, York, NE, reports that the mean maximum growing season temperature is decreasing at the rate ,0.01°C year,1. The results from non-irrigated sites indicated an increasing trend for the same parameters. The data from Halsey, NE, indicate a +0.01°C year,1 increase in this century. In addition, we have conducted similar analyses of temperature data for the National Climatic Data Center's Historical Climatic Network data set for the same locations. The results are similar to that obtained with the coop data set. Further investigation of dew-point temperature records for irrigated and non-irrigated sites also show an increasing and decreasing trend respectively. Therefore, we conclude that the land-use change in the Great Plains has modified near-surface temperature records. Copyright © 2004 Royal Meteorological Society [source] Phenotypic variation in growth trajectories in the Arctic charr Salvelinus alpinusJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 4 2003M. Björklund Abstract Animals with determinate growth have shown little variation in individual growth patterns, but similar analyses for animals with indeterminate growth have been lacking. We analysed the amount of phenotypic variation in growth patterns across ages among individuals of a hatchery-based population of Arctic charr, Salvelinus alpinus, Salmonidae, using the infinite-dimensional model and including the effects of group size structure. There was little phenotypic variation in growth trajectories: individuals that were small (in relation to the mean) early in life were among the smallest 2.5 years later. If the genetic variation reflects phenotypic variation, not much evolutionary change can be expected. Our results show that there are ecological conditions that determine the strong covariation of size across ages, most likely size-related dominance behaviour, which can mask the true variation of growth patterns. Thus, social interactions can have strong evolutionary effects on traits not directly involved in the behavioural interactions. [source] Searching for cluster substructure using APM and ROSAT dataMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2001V. Kolokotronis We present a detailed study of the morphological features of 22 rich galaxy clusters. Our sample is constructed from a cross-correlation of optical data with X-ray (0.1,2.4 keV) ROSAT pointed observations. We systematically compare cluster images and morphological parameters in an attempt to reliably identify possible substructure in both optical and the X-ray images. To this end, we compute various moments of the optical and X-ray surface-brightness distribution such as the ellipticities, centre-of-mass shifts and ellipsoidal orientations. We assess the significance of our results using Monte Carlo simulations. We find significant correlations between the optical and X-ray morphological parameters, indicating that in both parts of the spectrum it is possible to identify correctly the dynamical state of a cluster. Most of our clusters (17/22) have a good one-to-one correspondence between the optical and the X-ray images, and about 10 appear to have strong indications of substructure. This corresponds to a minimum percentage of order ,45 per cent, which is in very good accordance with other similar analyses. Finally, five out of 22 systems (,22 per cent) seem to have distinct subclumps in the optical which are not verified in the X-ray images, and thus are suspect of being due to optical projection effects. These results will serve as a useful guide in interpreting subsequent analyses of large optical cluster catalogues. [source] Smoothed analysis of some condition numbersNUMERICAL LINEAR ALGEBRA WITH APPLICATIONS, Issue 1 2006F. Cucker Abstract In this note we do a smoothed analysis, in the sense of (http://www-math.mit.edu/,spielman/SmoothedAnalysis/), of the condition number for the Moore,Penrose inverse. Usual average analysis follows in a trivial manner as follow similar analyses for the condition number of the polar factorization. Copyright © 2005 John Wiley & Sons, Ltd. [source] Representation and Agenda SettingPOLICY STUDIES JOURNAL, Issue 1 2004Bryan D. Jones We develop a new approach to the study of representation based on agenda setting and attention allocation. We ask the fundamental question: do the policy priorities of the public and of the government correspond across time? To assess the policy priorities of the mass public, we have coded the Most Important Problem data from Gallup polls across the postwar period into the policy content categories developed by the Policy Agendas Project (Baumgartner & Jones, 2002). Congressional priorities were assessed by the proportion of total hearings in a given year focusing on those same policy categories, also from the Agendas Project. We then conducted similar analyses on public laws and most important laws, similarly coded. Finally we analyzed the spatial structure of public and congressional agendas using the Shepard-Kruskal non-metric multidimensional scaling algorithm. Findings may be summarized as follows: First, there is an impressive congruence between the priorities of the public and the priorities of Congress across time. Second, there is substantial evidence of congruence between the priorities of the public and lawmaking in the national government, but the correspondence is attenuated in comparison to agendas. Third, although the priorities of the public and Congress are structurally similar, the location of issues within the structure differs between Congress and the general public. The public "lumps" its evaluation of the nations most important problems into a small number of categories. Congress "splits" issues out, handling multiple issues simultaneously. Finally, the public tends to focus on a very constrained set of issues, but Congress juggles many more issues. The article has strong implications for the study of positional representation as well, because for traditional representation to occur, there must be correspondence between the issue-priorities of the public and the government. We find substantial evidence for such attention congruence here. [source] Presence of a Community Health Center and Uninsured Emergency Department Visit Rates in Rural CountiesTHE JOURNAL OF RURAL HEALTH, Issue 1 2009FAAFP, FACPM, George Rust MD ABSTRACT:,Context: Community health centers (CHCs) provide essential access to a primary care medical home for the uninsured, especially in rural communities with no other primary care safety net. CHCs could potentially reduce uninsured emergency department (ED) visits in rural communities. Purpose: We compared uninsured ED visit rates between rural counties in Georgia that have a CHC clinic site and counties without a CHC presence. Methods: We analyzed data from 100% of ED visits occurring in 117 rural (non-metropolitan statistical area [MSA]) counties in Georgia from 2003 to 2005. The counties were classified as having a CHC presence if a federally funded (Section 330) CHC had a primary care delivery site in that county throughout the study period. The main outcome measure was uninsured ED visit rates among the uninsured (all-cause ED visits and visits for ambulatory care sensitive conditions). Poisson regression models were used to examine the relationship between ED rates and the presence of a CHC. To ensure that the effects were unique to the uninsured population, we ran similar analyses on insured ED visits. Findings: Counties without a CHC primary care clinic site had 33% higher rates of uninsured all-cause ED visits per 10,000 uninsured population compared with non-CHC counties (rate ratio [RR] 1.33, 95% confidence interval [CI] 1.11-1.59). Higher ED visit rates remained significant (RR 1.21, 95% CI 1.02-1.42) after adjustment for percentage of population below poverty level, percentage of black population, and number of hospitals. Uninsured ED visit rates were also higher for various categories of diagnoses, but remained statistically significant on multivariate analysis only for ambulatory care sensitive conditions (adjusted RR = 1.22, 95% CI 1.01-1.47). No such relationship was found for ED visit rates of insured patients (RR 1.06, 95% CI 0.92-1.22). Conclusions: The absence of a CHC is associated with a substantial excess in uninsured ED visits in rural counties, an excess not seen for ED visit rates among the insured. [source] Cortisol levels and measures of body composition in middle-aged and older menCLINICAL ENDOCRINOLOGY, Issue 1 2007Thomas G. Travison Summary Introduction, Similarities in the symptomatic expressions of excess adiposity and hypercortisolaemic conditions suggest that elevated glucocorticoid exposure may influence the pathogenesis of obesity. Circulating cortisol levels are not typically elevated in obese subjects, but data from large prospective samples are rare. We undertook an analysis to determine both cross-sectional and longitudinal associations between body composition and serum cortisol concentrations in a randomly chosen group of 999 community-dwelling men, aged 40,79 years. Methods, Data were obtained from the two follow-up waves of the Massachusetts Male Ageing Study (T2: 1995,97; T3: 2002,04). Partial correlation and multivariate regression analyses were used to estimate cross-sectional (T2) and longitudinal associations between serum cortisol concentrations and a range of measures of subjects' body composition, including weight, body mass index (BMI), waist circumference (WC), waist-to-hip girth ratio (WHR), and percentage body fat (measured by bioelectrical impedance at T3); similar analyses were conducted to assess the association between change (T2 to T3) in serum cortisol and simultaneous change in body composition parameters. Results, We observed weak negative associations between cortisol concentrations and all body composition parameters, with the exception of percentage body fat. Longitudinal results demonstrated similar relationships but associations were of lesser magnitude. T2 cortisol concentrations were not associated with change in body composition over time, whereas T2 body size was positively associated with longitudinal changes in cortisol concentrations, providing limited evidence that weight change drives changes in cortisol concentrations, rather than vice versa. Results were unchanged when age and other covariate effects were controlled. Conclusions, Circulating cortisol concentrations are somewhat lower in obese than in nonobese community-dwelling men. There is some evidence that excess adiposity presages increases in cortisol concentrations, rather than the reverse. However, this observation should be greeted with caution, as age-related weight loss , and not gain , was associated with simultaneous increases in serum cortisol concentrations. [source] Numerical Treatment of Seismic Accelerograms and of Inelastic Seismic Structural Responses Using Harmonic WaveletsCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2007Pol D. Spanos The effectiveness of the harmonic wavelets for capturing the temporal evolution of the frequency content of strong ground motions is demonstrated. In this regard, a detailed study of important earthquake accelerograms is undertaken and smooth joint time-frequency spectra are provided for two near-field and two far-field records; inherent in this analysis is the concept of the mean instantaneous frequency. Furthermore, as a paradigm of usefulness for aseismic structural purposes, a similar analysis is conducted for the response of a 20-story steel frame benchmark building considering one of the four accelerograms scaled by appropriate factors as the excitation to simulate undamaged and severely damaged conditions for the structure. The resulting joint time-frequency representation of the response time histories captures the influence of nonlinearity on the variation of the effective natural frequencies of a structural system during the evolution of a seismic event. In this context, the potential of the harmonic wavelet transform as a detection tool for global structural damage is explored in conjunction with the concept of monitoring the mean instantaneous frequency of records of critical structural responses. [source] Population Variability and Extinction RiskCONSERVATION BIOLOGY, Issue 6 2000John A. Vucetich We resolve this conflict by attributing negative measured relationships to a statistical artifact that arises because PV tends to be underestimated for populations with short persistence. Such populations do not go extinct quickly as a consequence of low intrinsic variability; instead, the measured variability is low because they go extinct so quickly. Consequently, any underlying positive relationship between PV and ER tends to be obscured. We conducted a series of analyses to evaluate this claim. Simulations showed that negative measured relationships are to be expected, despite an underlying positive relationship. Simulations also identified properties of data, minimizing this bias and thereby permitting meaningful analysis. Experimental data on laboratory populations of a bruchid beetle (Callosobruchus maculatus) supported the simulation results. Likewise, with an appropriate statistical approach (Cox regression on untransformed data), reanalysis of a controversial data set on British island bird populations revealed a significant positive association between PV and ER (p = 0.03). Finally, a similar analysis of time series for naturally regulated animal populations revealed a positive association between PV and quasiextinction risk (p < 0.01). Without exception, our simulation results, experimental findings, reanalysis of published data, and analysis of quasiextinction risk all contradict previous reports of negative or equivocal relationships. Valid analysis of meaningful data provides strong evidence that increased population variability leads to increased extinction risk. Resumen: Los modelos poblacionales generalmente predicen un mayor riesgo de extinción (ER) al aumentar la variabilidad poblacional ( PV ,), a pesar de ello, algunas pruebas empíricas han proporcionado resultados contradictorios. Nosotros hemos resuelto este conflicto mediante la atribución de mediciones de relaciones negativas a un producto estadístico que surge debido a que la PV tiende a ser subestimada para poblaciones de persistencia corta. Estas poblaciones no se extinguen rápidamente como resultado de una variabilidad intrínseca baja; por lo contrario, la variabilidad medida es baja debido a que las poblaciones se extinguen tan rápidamente. Consecuentemente, cualquier relación positiva subyacente entre la PV y el ER tienden a ser opacadas. Llevamos a cabo una serie de análisis para evaluar este argumento. Las simulaciones mostraron que las relaciones negativas medidas son de esperarse, a pesar de una relación positiva subyacente. Las simulaciones también identificaron propiedades de los datos que minimizan este sesgo y por lo tanto permiten un análisis significativo. Los datos experimentales en poblaciones de laboratorio de un coleóptero bruchidae (Callosobruchus maculatus) respaldan los resultados de las simulaciones. De la misma manera, el uso de una técnica estadística adecuada (por ejemplo, la regresión Cox en datos sin transformar), usada en la repetición del análisis de un juego de datos controvertidos de poblaciones de aves de la Isla Británica reveló una asociación positiva significativa entre la PV y el ER (p = 0.03). Finalmente, un análisis similar de series de tiempo para poblaciones de animales reguladas de manera natural revelaron una asociación positiva entre la PV y el riesgo de cuasi-extinción (p < 0.01). Sin excepciones, nuestros resultados de simulaciones, los resultados experimentales, la repetición del análisis de datos publicados, y el análisis de riesgo de cuasi-extinción contradicen informes previos de relaciones negativas o equívocas. Los análisis válidos de datos significativos proveen una evidencia sólida de que los incrementos en la variabilidad poblacional conducen a un incremento en el riego de extinción. [source] Possible Contribution of Central Gamma-Aminobutyric Acid Receptors to Resting Vascular Tone in Freely Moving RatsEXPERIMENTAL PHYSIOLOGY, Issue 5 2000Yumi Takemoto Previous studies have shown that central administration of GABA (gamma-aminobutyric acid), an inhibitory neurotransmitter, preferentially reduces hindquarters and carotid vascular resistances but not renal and coeliac vascular resistances in conscious rats. This study tested the hypothesis that these preferential actions of central GABA receptors are related to differences between vessels in resting autonomic vascular tone in freely moving rats. Rats were chronically implanted with intracisternal cannulas and/or electromagnetic probes to measure regional blood flows. In response to GABA administration, the changes in vascular resistance (arterial blood pressure/regional blood flow) of the hindquarters (n = 23) and carotid (n = 12) vascular beds were significantly and negatively correlated with basal vascular resistance. No such relationship was found for the renal (n = 21), coeliac (n = 13) and superior mesenteric (n = 23) vascular beds. This finding indicates that the responsiveness to GABA of brainstem pathways controlling the hindquarters and carotid vascular beds co-varies with resting resistance in hindquarters and carotid vessels. A similar analysis was performed, correlating the ongoing vascular resistance of each vessel with its response to ganglionic blockade by chlorisondamine. In this case, a significant negative correlation was also found for the hindquarters (n = 26) and carotid (n = 15) vascular beds, but not for the coeliac (n = 17) or superior mesenteric (n = 19) vessels. Together, these findings suggest that central GABA receptors accessible from the cisterna magna preferentially affect two vascular beds which, in the freely moving rat, show resting autonomic vascular tone. [source] NO synthase isoforms specifically modify peroxynitrite reactivityFEBS JOURNAL, Issue 19 2010Amandine Maréchal Nitric oxide synthases (NOSs) are multi-domain hemothiolate proteins that are the sole source of nitric oxide (NO) in mammals. NOSs can also be a source or a sink for peroxynitrite (PN), an oxidant that is suspected to be involved in numerous physiopathological processes. In a previous study, we showed that the oxygenase domain of the inducible NOS (iNOSoxy) reacts with PN and changes its oxidative reactivity [Maréchal A, Mattioli TA, Stuehr DJ & Santolini J (2007) J Biol Chem282, 14101,14112]. Here we report a similar analysis on two other NOS isoforms, neuronal NOS (nNOS) and a bacterial NOS-like protein (bsNOS). All NOSs accelerated PN decomposition, with accumulation of a similar heme intermediate. The kinetics of PN decomposition and heme transitions were comparable among NOSs. However, their effects on PN reactivity differ greatly. All isoforms suppressed PN two-electron oxidative activity, but iNOSoxy enhanced PN one-electron oxidation and nitration potencies, the oxygenase domain of nNOS (nNOSoxy) affected them minimally, and bsNOS abolished all PN reactivities. This led to the loss of both NOS and PN decomposition activities for nNOSoxy and iNOSoxy, which may be linked to the reported alterations in their electronic absorption spectra. Bacterial bsNOS was affected to a lesser extent by reaction with PN. We propose that these differences in PN reactivity among NOSs might arise from subtle differences in their heme pockets, and could reflect the physiological specificity of each NOS isoform, ranging from oxidative stress amplification (iNOS) to detoxification (bsNOS). [source] Resistance Is Not Futile: Liberating Captain Janeway from the Masculine-Feminine Dualism of LeadershipGENDER, WORK & ORGANISATION, Issue 4 2004Michèle A. BowringArticle first published online: 10 JUN 200 . . . the boundary between science-fiction and social reality is an optical illusion' (Haraway, 1990, p. 191) My underlying purpose in this article is to uncover the way in which research on leadership has been constrained by a reliance on the categories male-female and/or masculine-feminine for theorizing and for empirical work. I argue that both gender and leadership are caught within what Judith Butler calls the heterosexual matrix and that this has significant repercussions on leaders and leadership discourse. I use the character of Captain Kathryn Janeway from Star Trek: Voyager as a case study. I begin by analysing her leadership on the television series. I then perform a similar analysis of Janeway as she is represented in a text that subverts her gender by queering her character. I compare the two Janeways and the effect that the construction of each one's gender has on her leadership. In the conclusion I discuss ways in which we can use this analysis to move towards fluidity in the theorizing and practice of both gender and leadership. [source] Interactions between genetic and reproductive factors in breast cancer risk in a population-based sample of African-American familiesGENETIC EPIDEMIOLOGY, Issue 4 2002Valérie Chaudru Abstract Incidence of breast cancer (BC) varies among ethnic groups, with higher rates in white than in African-American women. Until now, most epidemiological and genetic studies have been carried out in white women. To investigate whether interactions between genetic and reproductive risk factors may explain part of the ethnic disparity in BC incidence, a genetic epidemiology study was conducted, between 1989 and 1994, at the Howard University Cancer Center (Washington, DC), which led to the recruitment of 245 African-American families. Segregation analysis of BC was performed by use of the class D regressive logistic model that allows for censored data to account for a variable age of onset of disease, as implemented in the REGRESS program. Segregation analysis of BC was consistent with a putative dominant gene effect (P < 0.000001) and residual sister-dependence (P < 0.0001). This putative gene was found to interact significantly with age at menarche (P = 0.048), and an interaction with a history of spontaneous abortions was suggested (P = 0.08). A late age at menarche increased BC risk in gene carriers but had a protective effect in non-gene carriers. A history of spontaneous abortions had a protective effect in gene carriers and increased BC risk in non-gene carriers. Our findings agree partially with a similar analysis of French families showing a significant gene × parity interaction and a suggestive gene × age at menarche interaction. Investigating gene × risk factor interactions in different populations may have important implications for further biological investigations and for BC risk assessment. Genet. Epidemiol. 22:285,297, 2002. © 2002 Wiley-Liss, Inc. [source] 3D Mapping of brain differences in native signing congenitally and prelingually deaf subjectsHUMAN BRAIN MAPPING, Issue 7 2010Natasha Leporé Abstract In the prelingual and congenital deaf, functional reorganization is known to occur throughout brain regions normally associated with hearing. However, the anatomical correlates of these changes are not yet well understood. Here, we perform the first tensor-based morphometric analysis of voxel-wise volumetric differences in native signing prelingual and congenitally deaf subjects when compared with hearing controls. We obtained T1-weighted scans for 14 native signing prelingual and congenitally deaf subjects and 16 age- and gender-matched controls. We used linear and fluid registration to align each image to a common template. Using the voxel-wise determinant of the Jacobian of the fluid deformation, significant volume increases, of up to 20%, were found in frontal lobe white matter regions including Broca's area, and adjacent regions involved in motor control and language production. A similar analysis was performed on hand-traced corpora callosa. A strong trend for group differences was found in the area of the splenium considered to carry fibers connecting the temporal (and occipital) lobes. These anatomical differences may reflect experience-mediated developmental differences in myelination and cortical maturation associated with prolonged monomodal sensory deprivation. Hum Brain Mapp, 2010. © 2009 Wiley-Liss, Inc. [source] Trends in the southern oscillation phenomenon and Australian rainfall and changes in their relationshipINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 3 2004Ramasamy Suppiah Abstract An attempt has been made to investigate decadal-scale trends in Australian rainfall and in the southern oscillation index (SOI) and their influence on the relationship between them. Monthly rainfall data from high-quality stations in Australia (from 1900 to 1995), India, Sri Lanka and Tahiti are used. The relationship between the SOI and Australian rainfall is positive, but shows decadal-scale variations during the past century. Although there were extended and severe El Niño events in the early 1990s and in 1997, Australia did not experience the expected severe rainfall deficiencies characteristic of previous events. However, severe drought conditions over eastern Australia were associated with a moderate El Niño event during 2002,03. Long-term fluctuations of March,May (MAM) rainfall show high-frequency variations, but trends during June,August (JJA), September,November (SON) and December,February (DJF) show low-frequency or decadal-scale variations. Trends and multi-decadal fluctuations in all-Australian spring (SON) and summer (DJF) rainfall are strongly dominated by rainfall trend fluctuations in northern and eastern Australia. Austral summer rainfall shows an increasing trend during the 1980s and 1990s, particularly in Queensland and New South Wales, despite the occurrence of extended and severe El Niños. However, some parts of New South Wales and Queensland experienced severe rainfall deficiencies during 2002,03 in conjunction with an El Niño event. The relationship between the SOI and rainfall on the interannual time scale is strong when the SOI and rainfall follow the same direction, but it is weak when they follow opposite directions on a decadal-time scale. The poor correlation during the 1920s and 1930s was due to a slightly increasing trend in the SOI and a stronger decreasing trend in rainfall. A weakening in the relationship between the SOI and rainfall in recent years, after the mid-1970s, is due to a small increase in rainfall in the 1980s and 1990s and a strong decrease in the SOI. Rainfall trends were enhanced (stronger decreases or increases) when the influence of the SOI (or El Niño-southern oscillation (ENSO)) was removed. Enhanced increases and decreases are particularly strong during SON and DJF, when the ENSO phenomenon is at the mature stage and also the influence on Australian rainfall is strong. The increasing trend in rainfall during the 1980s and 1990s in some parts of eastern Australia and the decreasing trend in the SOI result in more rainfall for a given SOI compared with the same SOI during the previous period, i.e. before the mid-1970s. A similar analysis was carried out for two periods, before and after 1972, for Tahiti, India and Sri Lanka. The upward or downward shift in regression lines is very clear during the season, that shows a strong relationship between rainfall and the SOI. Moreover, strengthening or weakening of the relationship between rainfall and the SOI is largely dependent on their multi-decadal variations and trends during the past century. Increases in rainfall during the 1980s and the 1990s and decreases in the SOI have weakened their relationship, both in Australia and India. Such a relationship gives more rainfall for a given SOI after 1973. The pattern was reversed for Sri Lanka, where rainfall during the second intermonsoon season has decreased. Analyses of trends in temperature at Darwin and Tahiti and of rainfall over Australia, India, Tahiti and Sri Lanka suggest a regional-scale change in climate, whereas the SOI reflects a change in the large-scale circulation pattern over the Indo-Pacific region after the mid-1970s. Copyright © 2004 Royal Meteorological Society [source] An integrative quantitative model of factors influencing the course of anorexia nervosa over timeINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 4 2009Michal Yackobovitch-Gavan PhD Abstract Objective: To identify factors influencing the course of anorexia nervosa (AN) over time. Method: Former female patients with AN (36 remitted and 24 nonremitted) and 31 healthy females responded to standardized interviews and self-rating questionnaires. Remitted patients maintained normal eating, normal weight, and regular menses for the past 12 months. Patients not fulfilling these criteria were considered nonremitted. Results: Using logistic regression, we identified that number of hospitalizations, duration of ambulatory treatment, past vegetarianism, past anxiety, and childhood sexual abuse differentiated remitted from nonremitted patients, predicting nonremission. A similar analysis identified that elevated follow-up vegetarianism and eating-related concerns and lower body mass index (BMI) differentiated remitted from nonremitted patients, contributing to nonremission. Univariate analyses identified that remitted patients had elevated anxiety and eating-related obsessionality compared with the controls, suggesting these variables to potentially predispose to AN. Discussion: Elevated anxiety and eating-related obsessionality may increase the risk for the development of AN and for nonremission. © 2008 by Wiley Periodicals, Inc. Int J Eat Disord 2009 [source] Gene expression profiling of aging in multiple mouse strains: identification of aging biomarkers and impact of dietary antioxidantsAGING CELL, Issue 4 2009Sang-Kyu Park Summary We used DNA microarrays to identify panels of transcriptional markers of aging that are differentially expressed in young (5 month) and old (25 month) mice of multiple inbred strains (129sv, BALB/c, CBA, DBA, B6, C3H and B6C3F1). In the heart, age-related changes of five genes were studied throughout the mouse lifespan: complement component 4, chemokine ligand 14, component of Sp100-rs, phenylalanine hydroxylase and src family associated phosphoprotein 2. A similar analysis in the brain (cerebellum) involved complement component 1q (alpha polypeptide), complement component 4, P lysozyme structural, glial fibrillary acidic protein and cathepsin S. Caloric restriction (CR) inhibited age-related expression of these genes in both tissues. Parametric analysis of gene set enrichment identified several biological processes that are induced with aging in multiple mouse strains. We also tested the ability of dietary antioxidants to oppose these transcriptional markers of aging. Lycopene, resveratrol, acetyl- l -carnitine and tempol were as effective as CR in the heart, and ,-lipoic acid and coenzyme Q10 were as effective as CR in the cerebellum. These findings suggest that transcriptional biomarkers of aging in mice can be used to estimate the efficacy of aging interventions on a tissue-specific basis. [source] Liver carcinogen aflatoxin B1 as an inducer of mitotic recombination in a human cell lineMOLECULAR CARCINOGENESIS, Issue 3 2001Peter Markus Stettler Abstract The mycotoxin aflatoxin B1 (AFB1) is one of the most potent rodent and human liver carcinogens. Upon cytochrome P450,specific metabolism, it induces mutations as well as mitotic recombination events in in vitro systems. We have found that in the lower eukaryote yeast, the recombinagenic activity of AFB1 surpasses its mutagenic activity, and we speculated on possible consequences in terms of the mechanism of liver carcinogenesis. In this study we investigated whether the recombinagenic activity of AFB1 also would be identified in human cells. To address this question, we followed the fate of a heterozygous thymidine kinase (tk) allele in the human lymphoblastoid cell line TK6 upon exposure to AFB1. Individual mutants that had lost tk activity were subjected to loss of heterozygosity analysis of the tk locus and its flanking markers. Fluorescence in situ hybridization analysis on chromosome 17 also was performed. In parallel, a similar analysis was performed on TK6 cells exposed to the alkylating agent N -nitrosomethylurea, a well-known classic point mutagen. Our analysis showed a difference in the molecular mechanism leading to inactivation of the tk allele upon exposure to these two mutagens. In AFB1 -exposed cells the fraction of recombination-derived mutants predominated, whereas in N -nitrosomethylurea,exposed cells the fraction of point mutants was higher. Thus, the recombinagenic activity of AFB1 previously identified in a lower eukaryote also was found in the human cell line TK6. Our data support the hypothesis that mitotic recombination represents a central mechanism of action in AFB1 -induced liver carcinogenesis. © 2001 Wiley-Liss, Inc. 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