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Selected AbstractsRegional GPS data confirm high strain accumulation prior to the 2000 June 4 Mw= 7.8 earthquake at southeast SumatraGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 3 2001G. W. Michel Summary Site velocities derived from repeated measurements in a regional GPS network in Southeast Asia help to constrain the motion of tectonic blocks as well as slip rates along major faults in the area. Using 3-D forward dislocation modelling, the influence of seismic elastic loading and unloading on the measured site motions are approximated. Results suggest that the northwestern Sunda arc is fully coupled seismogenically, whereas its eastern part along Java shows localized deformation. Higher horizontal velocity gradients than expected from the modelling of a fully coupled plate interface west of Manila in the Philippines suggest that deformation may be localized there. Assuming that geodetically derived convergence represents long-term rates, accumulated geodetic moments are compared to those derived using seismic data from 1977 to 2000 (Harvard CMT catalogue). If areas displaying localized deformation are dominated by creep processes, the largest difference between accumulated and seismically released deformation is located where the 2000 June 4 Mw = 7.8 Sumatra earthquake occurred. [source] X-ray crystallographic analysis and differential scanning calorimetry of two polymorphic forms of 2,6-diphenyl-1,4-dithiinHETEROATOM CHEMISTRY, Issue 6 2004Xuehua Piao 2,6-Diphenyl-1,4-dithiin 2 exists in the two polymorphic forms. The dithiin 2L, mp 62,63°C, was assigned as the metastable form, while the dithiin 2H, mp 79,80°C, was assigned as the stable form, mainly on the basis of differential scanning calorimetry (DSC) analysis. X-Ray crystallographic analysis showed that the largest difference in the molecular structure between 2L and 2H is found in the coplanarity between the benzene ring and the double bond part of the dithiin ring; the benzene ring and the double bond are nearly coplanar for 2L, whereas these are far from being coplanar for 2H. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:424,427, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20035 [source] Prey dispersal rate affects prey species composition and trait diversity in response to multiple predators in metacommunitiesJOURNAL OF ANIMAL ECOLOGY, Issue 5 2010Jennifer G. Howeth Summary 1.,Recent studies indicate that large-scale spatial processes can alter local community structuring mechanisms to determine local and regional assemblages of predators and their prey. In metacommunities, this may occur when the functional diversity represented in the regional predator species pool interacts with the rate of prey dispersal among local communities to affect prey species diversity and trait composition at multiple scales. 2.,Here, we test for effects of prey dispersal rate and spatially and temporally heterogeneous predation from functionally dissimilar predators on prey structure in pond mesocosm metacommunities. An experimental metacommunity consisted of three pond mesocosm communities supporting two differentially size-selective invertebrate predators and their zooplankton prey. In each metacommunity, two communities maintained constant predation and supported either Gyrinus sp. (Coleoptera) or Notonecta ungulata (Hemiptera) predators generating a spatial prey refuge while the third community supported alternating predation from Gyrinus sp. and N. ungulata generating a temporal prey refuge. Mesocosm metacommunities were connected at either low (0·7% day,1) or high (10% day,1) planktonic prey dispersal. The diversity, composition and body size of zooplankton prey were measured at local and regional (metacommunity) scales. 3.,Metacommunities experiencing the low prey dispersal rate supported the greatest regional prey species diversity (H') and evenness (J'). Neither dispersal rate nor predation regime affected local prey diversity or evenness. The spatial prey refuge at low dispersal maintained the largest difference in species composition and body size diversity between communities under Gyrinus and Notonecta predation, suggesting that species sorting was operating at the low dispersal rate. There was no effect of dispersal rate on species diversity or body size distribution in the temporal prey refuge. 4.,The frequency distribution, but not the range, of prey body sizes within communities depended upon prey dispersal rate and predator identity. Taken together, these results demonstrate that prey dispersal rate can moderate the strength of predation to influence prey species diversity and the local frequency distribution of prey traits in metacommunities supporting ecologically different predators. [source] Physiologic Effects of the TASER After ExerciseACADEMIC EMERGENCY MEDICINE, Issue 8 2009Gary M. Vilke MD Abstract Objectives:, Incidents of sudden death following TASER exposure are poorly studied, and substantive links between TASER exposure and sudden death are minimal. The authors studied the effects of a single TASER exposure on markers of physiologic stress in humans. Methods:, This prospective, controlled study evaluated the effects of a TASER exposure on healthy police volunteers after vigorous exercise, compared to a subsequent, identical exercise session that was not followed by TASER exposure. Subjects exercised to 85% of predicted heart rate (HR) on an ergometer and then were given a standard 5-second TASER activation. Measures before and for 60 minutes after the TASER activation included minute ventilation, tidal volume, respiratory rate, end-tidal pCO2, oxygen saturation, HR, blood pressure (systolic BP/diastolic BP), 12-lead electrocardiogram, and arterialized blood for pH, pO2, pCO2, and lactate. Each subject repeated the exercise and data collection session on a subsequent data, without TASER activation. Data were analyzed using paired Student's t-tests with differences and 95% confidence intervals (CIs). Statistical significance was adjusted for multiple comparisons. Results:, A total of 25 officers (21 men and 4 women) completed both portions of the study. After adjusting for multiple comparisons, the TASER group was significantly higher for systolic BP at baseline (difference of 14.1, 95% CI = 8.7 to 19.5, p < 0.001) and HR at 5, 30, and 60 minutes with the largest difference at 30 minutes (difference of 7.0, 95% CI = 2.5 to 11.5, p = 0.004). There were no other significant differences between the two groups in any other measure at any time. Conclusions:, A 5-second exposure of a TASER following vigorous exercise to healthy law enforcement personnel does not result in clinically significant changes in ventilatory or blood parameters of physiologic stress. [source] MicroRNA-140 is expressed in differentiated human articular chondrocytes and modulates interleukin-1 responsesARTHRITIS & RHEUMATISM, Issue 9 2009Shigeru Miyaki Objective MicroRNA (miRNA) are a class of noncoding small RNAs that act as negative regulators of gene expression. MiRNA exhibit tissue-specific expression patterns, and changes in their expression may contribute to pathogenesis. The objectives of this study were to identify miRNA expressed in articular chondrocytes, to determine changes in osteoarthritic (OA) cartilage, and to address the function of miRNA-140 (miR-140). Methods To identify miRNA specifically expressed in chondrocytes, we performed gene expression profiling using miRNA microarrays and quantitative polymerase chain reaction with human articular chondrocytes compared with human mesenchymal stem cells (MSCs). The expression pattern of miR-140 was monitored during chondrogenic differentiation of human MSCs in pellet cultures and in human articular cartilage from normal and OA knee joints. We tested the effects of interleukin-1, (IL-1,) on miR-140 expression. Double-stranded miR-140 (ds,miR-140) was transfected into chondrocytes to analyze changes in the expression of genes associated with OA. Results Microarray analysis showed that miR-140 had the largest difference in expression between chondrocytes and MSCs. During chondrogenesis, miR-140 expression in MSC cultures increased in parallel with the expression of SOX9 and COL2A1. Normal human articular cartilage expressed miR-140, and this expression was significantly reduced in OA tissue. In vitro treatment of chondrocytes with IL-1, suppressed miR-140 expression. Transfection of chondrocytes with ds,miR-140 down-regulated IL-1,,induced ADAMTS5 expression and rescued the IL-1,,dependent repression of AGGRECAN gene expression. Conclusion This study shows that miR-140 has a chondrocyte differentiation,related expression pattern. The reduction in miR-140 expression in OA cartilage and in response to IL-1, may contribute to the abnormal gene expression pattern characteristic of OA. [source] Differences in spatial predictions among species distribution modeling methods vary with species traits and environmental predictorsECOGRAPHY, Issue 6 2009Alexandra D. Syphard Prediction maps produced by species distribution models (SDMs) influence decision-making in resource management or designation of land in conservation planning. Many studies have compared the prediction accuracy of different SDM modeling methods, but few have quantified the similarity among prediction maps. There has also been little systematic exploration of how the relative importance of different predictor variables varies among model types and affects map similarity. Our objective was to expand the evaluation of SDM performance for 45 plant species in southern California to better understand how map predictions vary among model types, and to explain what factors may affect spatial correspondence, including the selection and relative importance of different environmental variables. Four types of models were tested. Correlation among maps was highest between generalized linear models (GLMs) and generalized additive models (GAMs) and lowest between classification trees and GAMs or GLMs. Correlation between Random Forests (RFs) and GAMs was the same as between RFs and classification trees. Spatial correspondence among maps was influenced the most by model prediction accuracy (AUC) and species prevalence; map correspondence was highest when accuracy was high and prevalence was intermediate (average prevalence for all species was 0.124). Species functional type and the selection of climate variables also influenced map correspondence. For most (but not all) species, climate variables were more important than terrain or soil in predicting their distributions. Environmental variable selection varied according to modeling method, but the largest differences were between RFs and GLMs or GAMs. Although prediction accuracy was equal for GLMs, GAMs, and RFs, the differences in spatial predictions suggest that it may be important to evaluate the results of more than one model to estimate the range of spatial uncertainty before making planning decisions based on map outputs. This may be particularly important if models have low accuracy or if species prevalence is not intermediate. [source] Sensitivity of an Arctic regional climate model to the horizontal resolution during winter: implications for aerosol simulationINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 11 2005Eric Girard Abstract Our ability to properly simulate current climate and its future change depends upon the exactitude of the physical processes that are parameterized on the one hand, and on model configuration on the other hand. In this paper, we focus on the latter and investigate the effect of the horizontal grid resolution on the simulation of a month of January over the Arctic. A limited-area numerical climate model is used to simulate the month of January 1990 over a grid that includes the Arctic and sub-Arctic regions. Two grid resolutions are used: 50 km and 100 km. Results show that finer details appear for regional circulation, temperature, and humidity when increasing horizontal resolution. This is particularly true for continental and sea ice boundaries, which are much better resolved by high-resolution model simulations. The Canadian Archipelago and rivers in northern Russia appear to benefit the most from higher horizontal resolution. High-resolution simulations capture some frozen rivers and narrow straits between islands. Therefore, much colder surface air temperature is simulated over these areas. Precipitation is generally increased in those areas and over topography due to a better representation of surface heterogeneities when increasing resolution. Large-scale atmospheric circulation is substantially changed when horizontal resolution is increased. Feedback processes occur between surface air temperature change over heterogeneous surfaces and atmospheric circulation. High-resolution simulations develop a stronger polar vortex. The mean sea-level pressure increases over the western Arctic and Iceland and decreases over the eastern Arctic. This circulation leads to a substantial cooling of the eastern Arctic and enhanced synoptic activity over the Arctic associated with an intensification of the baroclinic zone. Aerosol mass loading, which is simulated explicitly in this model, is significantly altered by the grid resolution change with the largest differences in aerosol concentration over areas where precipitation and atmospheric circulation are the most affected. The implications of this sensitivity study to the evaluation of indirect radiative effects of anthropogenic aerosols are discussed. Copyright © 2005 Royal Meteorological Society. [source] Low-temperature-driven early spawning migration of a temperate marine fishJOURNAL OF ANIMAL ECOLOGY, Issue 2 2004David W. Sims Summary 1It is often assumed that the timing of annual migrations of marine fish to spawning grounds occurs with very little change over time. However, it is unclear how much migration is influenced by climate change in marine species that spawn at sea but spend most time in estuarine conditions, especially as thermal regimes in estuaries may differ significantly from those in the open sea. 2Migration phenology was studied in a population of flounder, Platichthys flesus (L.) off south-west England using high-temporal resolution trawling data over a 13-year period. 3Flounder migrated from their estuarine habitat to spawning grounds at sea some 1,2 months earlier in years that were up to 2 °C cooler. Flounder arrived on the spawning grounds over a shorter time period (2,6 days) when colder than normal conditions prevailed in the estuary, compared to warmer years (12,15 days). This suggests that they were responding to low temperatures by exhibiting a more synchronous, population-level early migration. 4The timing of migration was earlier when the largest differences in temperatures between near-estuary and offshore environments occurred, differences that were related significantly to cold, negative phases of the North Atlantic Oscillation (NAO). 5Flounder migration phenology appears to be driven to a large extent by short-term, climate-induced changes in the thermal resources of their overwintering habitat. This suggests that climate fluctuations characterizing the NAO may have significant effects on the timing of the peak abundance of fish populations generally, which, in turn, may have implications for fisheries management. [source] Thresholds in landscape connectivity and mortality risks in response to growing road networksJOURNAL OF APPLIED ECOLOGY, Issue 5 2008Jacqueline L. Frair Summary 1The ecological footprint of a road may extend for several kilometres with overlapping effects from neighbouring roads causing a nonlinear accumulation of road effects in the landscape. Availability of preferred habitat, spatial dependencies between roads and habitat types, and fidelity to traditionally used areas further confound our ability to predict population-level responses of animals to growing road networks. 2To isolate these effects, we developed an individually based movement model using elk Cervus elaphus L. as a model system. Empirically derived movement rules redistributed elk under different amounts of preferred habitat (clearcuts), road densities, and road development schemes. We tracked potential mortality risk (given time spent near roads) and emigration rates (given declining accessibility of foraging habitat). 3Design of the road network accounted for up to 30,55% difference in mortality risk and emigration rates, with the largest differences occurring at intermediate road densities (1,1·5 km km,2) when road effects began to saturate the landscape. Maintaining roads in association with clearcuts caused a decline in habitat accessibility equivalent to replacing 50,75% of these foraging patches with conifer forest. A nine-fold difference in potential emigration was observed after varying elk tolerance for declining habitat accessibility despite holding local movement biases constant. 4Elk responses to growing road networks were non-linear, exposing thresholds for road density that were reflected in the home range occupancy patterns of a large sample of elk in the region. 5Synthesis and applications. Our approach provides a means of scaling-up complex movement decisions to population-level redistribution, separating the confounding effects of landscape context from road effects, and exposing thresholds in connectivity and mortality risks for wildlife caused by infrastructure growth. Our model indicated that road densities , 0·5 km km,2 yielded the highest probability of elk occurrence where elk were hunted (and sensitive to roads), but disassociating roads from foraging habitats or managing human access to roads may maintain effective elk habitat at substantially higher road densities. [source] Responses of periphyton and insects to experimental manipulation of riparian buffer width along forest streamsJOURNAL OF APPLIED ECOLOGY, Issue 6 2003Peter M. Kiffney Summary 1Riparian trees regulate aquatic ecosystem processes, such as inputs of light, organic matter and nutrients, that can be altered dramatically when these trees are harvested. Riparian buffers (uncut strips of vegetation) are widely used to mitigate the impact of clear-cut logging on aquatic ecosystems but there have been few experimental assessments of their effectiveness. 2Forests along 13 headwater stream reaches in south-western British Columbia, Canada, were clear-cut in 1998, creating three riparian buffer treatments (30-m buffer, 10-m buffer and clear-cut to the stream edge), or left as uncut controls, each treatment having three or four replicates. 3We predicted that periphyton biomass and insect consumers would increase as buffer width decreased, because of increased solar flux. We used two complementary studies to test this prediction. 4In one study, we compared benthic communities before and after logging in all 13 streams; a second study focused on periphyton and insect colonization dynamics over 6-week periods in each of four seasons in four streams, one in each treatment. 5Photosynthetically active radiation, and mean and maximum water temperature, increased as buffer width narrowed. 6Periphyton biomass, periphyton inorganic mass and Chironomidae abundance also increased as buffer width narrowed, with the largest differences occurring in the clear-cut and 10-m buffer treatments. 7Photosynthetically active radiation, water temperature, periphyton biomass and periphyton inorganic mass were significantly greater in the 30-m buffer treatment than in controls during some seasons. 8.,Synthesis and applications. We have shown that a gradient of riparian buffer widths created a gradient in light and temperature that led to non-linear increases in periphyton biomass and insect abundance. For example, Chironomidae abundance was generally greater in the 10-m and 30-m buffer treatments than in controls, whereas this was not always the case in the clear-cut treatment. This pattern may be due to the high sediment content of the periphyton mat in the clear-cut treatment, which potentially limited the response of some insects to increased food resources. Overall, our results indicate that uncut riparian buffers of 30-m or more on both sides of the stream were needed to limit biotic and abiotic changes associated with clear-cut logging in headwater, forested watersheds. [source] Differences in health-related quality of life between older nursing home residents without cognitive impairment and the general population of NorwayJOURNAL OF CLINICAL NURSING, Issue 9 2008Jorunn Drageset RN Aim., To advance the understanding of health-related quality of life among older nursing home residents by assessing their health-related quality of life and comparing this with norms from the general population. Methods., The study used a two-group cross-sectional comparative design. The samples comprised 227 nursing home residents aged 65,102 years with at least six months' residence and a representative population sample of 1137 Norwegian citizens aged 65,102 years. All nursing home residents had a Clinical Dementia Rating Scale score ,0·5 and were capable of conversing. The respondents provided demographic information and were surveyed using the SF-36 Health Survey. We used univariate and multivariate linear models to identify possible differences in health-related quality of life between the nursing home residents and the general population, controlled for age, sex, marital status and education. Results., After adjustment for age, group, sex, marital status and education, the nursing home residents scored significantly higher on bodily pain and on physical and emotional role limitation and significantly lower on the other SF-36 subscales, except social functioning, with the largest differences for physical functioning (mean nursing home 23·2 and mean general population 62·9). The general population scores on all subscales generally increased with increasing education but not among the nursing home residents. Conclusions., The mean SF-36 scale scores differed markedly between the nursing home residents and the general population, with the nursing home residents generally scoring lower. The association with background variables known to be related to health-related quality of life differed between the groups. Healthcare professionals should increase attention to health-related quality of life among nursing home residents, periodically assess health-related quality of life and consider interventions that may improve health-related quality of life in older institutionalised populations. Relevance to clinical practice., This study highlights the role of nurses and other health professionals in ensuring that nursing home residents have opportunities to improve their health-related quality of life. [source] The effect of the film H content on the crystallization of laser processed and thermally annealed HWCVD a-Si:HPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 3-4 2010A. H. Mahan Abstract We demonstrate the use of laser processing to affect the nucleation of crystallites in thermally annealed HWCVD a-Si:H thin films. The influence of film H content is investigated by XRD measurements during in situ 600 °C thermal anneal on both as grown films and on films that have been laser irradiated. All laser irradiated films show a reduced incubation time (,o) for crystallization compared to as-grown films, with the largest differences exhibited for samples with higher film H. We show that a recently developed model for a nucleation center in a-Si:H can be used to explain how the film H content affects this change in ,o and also predict the magnitude of this change with laser processing (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] A phenomenological study of the mechanical properties of long-fiber filled injection-molded thermoplastic compositesPOLYMER COMPOSITES, Issue 5 2000V. K. Stokes Tensile and flexural tests on specimens cut from rectangular injection-molded plaques show that long-fiber filled thermoplastic composites are complex, non-homogeneous, anistropic material systems. Like all fiber-filled materials, they exhibit through-thickness nonhomogeneity as indicated by differences between tensile and flexural properties. The in-plane orientation of fibers in through-thickness layers causes the material to have in-plane anisotropic properties. However, these long-fiber filled materials exhibit an unexpectedly large level of in-plane nonhomogeneity. Also, the effective mechanical properties of these materials are strongly thickness dependent. The thinnest plaques exhibit the largest differences between the flow and cross-flow tensile properties. These differences decrease with increasing thickness. A methodology for part design with this class of materials is discussed. [source] Who Starts Treatment: Engagement in the NIDA Collaborative Cocaine Treatment StudyTHE AMERICAN JOURNAL ON ADDICTIONS, Issue 1 2002Lynne Siqueland Ph.D. This study addressed the role of demographic variables, severity of drug dependence, and drug-related problems in facilitating or impeding engagement into a research treatment. Patients were tracked through various stages of entry for the research treatment: phone screening, intake, and randomization to treatment. Results suggested that certain demographic factors put patients more at risk for dropping out at intake and randomization. African-American and unemployed patients were less likely to stay in treatment at both stages, with largest differences at intake. Younger patients were less likely to complete both phases, with bigger differences noted at randomization. Patients with more days of cocaine use and patients referred from advertisements were less likely to keep their intake appointments. [source] Mg2+ and memantine block of rat recombinant NMDA receptors containing chimeric NR2A/2D subunits expressed in Xenopus laevis oocytesTHE JOURNAL OF PHYSIOLOGY, Issue 1 2008David C. Wrighton N -methyl- d -aspartate receptors (NMDARs) display differences in their sensitivity to the channel blockers Mg2+ and memantine that are dependent on the identity of the NR2 subunit present in the receptor,channel complex. This study used two-electrode voltage-clamp recordings from Xenopus laevis oocytes expressing recombinant NMDARs to investigate the actions of Mg2+ and memantine at the two NMDARs displaying the largest differences in sensitivity to these blockers, namely NR1/NR2A and NR1/NR2D NMDARs. In addition, NR2A/2D chimeric subunits have been employed to examine the effects of pore-forming elements and ligand-binding domains (LBD) on the potency of the block produced by each of these inhibitors. Our results show that, as previously documented, NR2D-containing NMDARs are less sensitive to voltage-dependent Mg2+ block than their NR2A-containing counterparts. The reduced sensitivity is determined by the M1M2M3 membrane-associated regions, as replacing these regions in NR2A subunits with those found in NR2D subunits results in a ,10-fold reduction in Mg2+ potency. Intriguingly, replacing the NR2A LBD with that from NR2D subunits results in a ,2-fold increase in Mg2+ potency. Moreover, when responses mediated by NR1/NR2A NMDARs are evoked by the partial agonist homoquinolinate, rather than glutamate, Mg2+ also displays an increased potency. Memantine block of glutamate-evoked currents is most potent at NR1/NR2D NMDARs, but no differences are observed in its ability to inhibit NR2A-containing or NR2A/2D chimeric NMDARs. We suggest that the potency of block of NMDARs by Mg2+ is influenced not only by pore-forming regions but also the LBD and the resulting conformational changes that occur following agonist binding. [source] A genome map of divergent artificial selection between Bos taurus dairy cattle and Bos taurus beef cattleANIMAL GENETICS, Issue 2 2009B. J. Hayes Summary A number of cattle breeds have become highly specialized for milk or beef production, following strong artificial selection for these traits. In this paper, we compare allele frequencies from 9323 single nucleotide polymorphism (SNP) markers genotyped in dairy and beef cattle breeds averaged in sliding windows across the genome, with the aim of identifying divergently selected regions of the genome between the production types. The value of the method for identifying selection signatures was validated by four sources of evidence. First, differences in allele frequencies between dairy and beef cattle at individual SNPs were correlated with the effects of those SNPs on production traits. Secondly, large differences in allele frequencies generally occurred in the same location for two independent data sets (correlation 0.45) between sliding window averages. Thirdly, the largest differences in sliding window average difference in allele frequencies were found on chromosome 20 in the region of the growth hormone receptor gene, which carries a mutation known to have an effect on milk production traits in a number of dairy populations. Finally, for the chromosome tested, the location of selection signatures between dairy and beef cattle was correlated with the location of selection signatures within dairy cattle. [source] | ||||||||||||||||