52 resultados para 520


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The porcine circovirus type 2 (PCV2) genome encodes three major open reading frames (ORFs) encoding the replicase proteins (ORF1), the viral capsid protein (ORF2), and a protein with suggested apoptotic activity (ORF3). Previous phylogenetic analyses of complete genome sequences of PCV2 from GenBank have demonstrated 95-100% intra-group nucleotide sequence identity. However, although these isolates were readily grouped into clusters and clades, there was no correlation between the occurrence of specific PCV2 genotypes and the geographic origin or health status of the pig. In the present study, a unique dataset from a field study spanning the years pre and post the recognition of postweaning multisystemic wasting syndrome (PMWS) in Sweden was utilized. Using this dataset it was possible to discriminate three Swedish genogroups (SG1-3) of PCV2, of which SG1 was recovered from a pig on a healthy farm ten years before the first diagnosis of PMWS in Sweden. The SG1 PCV2/ORF2 gene sequence has been demonstrated to exhibit a high genetic stability over time and has subsequently only been demonstrated in samples from pigs on nondiseased farms. In contrast, SG2 was almost exclusively found on farms that had only recently broken down with PMWS whereas the SG3 genogroup predominated in pigs from PMWS-affected farms. These results further support the results obtained from earlier in vitro and in vivo experimental models and suggest the association of specific PCV2 genogroups with diseased and nondiseased pigs in the field.

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Use of nitrofuran drugs in food-producing animals has been prohibited within the EU because they may represent a public health risk. Monitoring compliance with the ban has focused on the detection of protein-bound nitrofuran metabolites which, in contrast to the parent compounds, are stable and persist in animal tissues. As part of the "FoodBRAND" project, an extensive survey of pork was undertaken across 15 European countries. Samples (n = 1500) purchased at retail outlets were analysed for the nitrofuran metabolites AOZ, AMOZ, AHD and SEM using LC-MS/MS determination of nitrobenzaldehyde derivatives. Limits of quantification for the method were 0.1 mug/kg (AOZ, AMOZ), 0.2 mug/kg (SEM) and 0.5 mug/kg (AHD). Of the 1500 samples tested, measurable residues of nitrofuran metabolites were confirmed in 12 samples (0.8% incidence overall) of which 10 samples were purchased in Portugal (AOZ, 0.3 mug/kg; AMOZ, 0.2-0.6 mug/kg) and one sample each in Italy (AMOZ, 1.0 mug/kg) and Greece (AOZ, 3.0 mug/kg). (C) 2004 Elsevier B.V. All rights reserved.

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The distribution of glacial cirques upon the Kamchatka peninsula, Far Eastern Russia, is systematically mapped from satellite images and digital elevation model data. A total of 3,758 cirques are identified, 238 of which are occupied by active glaciers. The morphometry of the remaining 3,520 cirques is analysed. These cirques are found to show a very strong N bias in their azimuth (orientation), likely resulting from aspect-related variations in insolation. The strength of this N bias is considered to indicate that former glaciation upon the peninsula was often ‘marginal’, and mainly of cirque-type, with peaks extending little above regional equilibrium-line altitudes. This is supported by the fact that S and SE-facing cirques are the highest in the dataset, suggesting that glacier-cover was rarely sufficient to allow S and SE-facing glaciers to develop at low altitudes. The strength of these azimuth-related variations in cirque altitude is thought to reflect comparatively cloud-free conditions during former periods of glaciation. It is suggested that these characteristics, of marginal glaciation and comparatively cloud-free conditions, reflect the region’s former aridity, which was likely intensified at the global Last Glacial Maximum, and during earlier periods of ice advance, as a result of the development of negative pressure anomalies over the North Pacific (driven by the growth of the Laurentide Ice Sheet), combined with other factors, including an increase in the extent and duration of sea ice, a reduction in global sea levels, cooler sea surface temperatures, and the localised growth of mountain glaciers. There is published evidence to suggest extensive glaciation of the Kamchatka Peninsula at times during the Late Quaternary, yet the data presented here appears to suggest that such phases were comparatively short-lived, and that smaller cirque-type glaciers were generally more characteristic of the period.

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The transport properties (adsorption and aggregation behavior) of virus-like particles (VLPs) of two strains of norovirus ("Norwalk" GI.1 and "Houston" GII.4) were studied in a variety of solution chemistries. GI.1 and GII.4 VLPs were found to be stable against aggregation at pH 4.0-8.0. At pH 9.0, GI.1 VLPs rapidly disintegrated. The attachment efficiencies (a) of GI.1 and GII.4 VLPs to silica increased with increasing ionic strength in NaCl solutions at pH 8.0. The attachment efficiency of GI.1 VLPs decreased as pH was increased above the isoelectric point (pH 5.0), whereas at and below the isoelectric point, the attachment efficiency was erratic. Ca(2+) and Mg(2+) dramatically increased the attachment efficiencies of GI.1 and GII.4 VLPs, which may be due to specific interactions with the VLP capsids. Bicarbonate decreased attachment efficiencies for both GI.1 and GII.4 VLPs, whereas phosphate decreased the attachment efficiency of GI.1, while increasing GII.4 attachment efficiency. The observed differences in GI.1 and GII.4 VLP attachment efficiencies in response to solution chemistry may be attributed to differential responses of the unique arrangement of exposed amino acid residues on the capsid surface of each VLP strain.

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We present time-resolved J-band spectroscopy of the short-period cataclysmic variable SDSS J143317.78+101123.3. We detect absorption lines from the sub-stellar donor star in this system, which contributes 38 +/- 5 per cent to the J-band light. From the relative strengths of the absorption lines in the J band, we estimate the spectral type of the donor star to be L2 +/- 1. These data are the first spectroscopic detection of a donor with a confirmed sub-stellar mass in a cataclysmic variable, and the spectral type is consistent with that expected from semi-empirical evolutionary models.

Using skew mapping, we have been able to derive an estimate for the radial velocity of the donor of K-d = 520 +/- 60 km/s. This value is consistent with, though much less precise than, predictions from mass determinations found via photometric fitting of the eclipse light curves.

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Background: Durkheim’s seminal historical study demonstrated that religious affiliation reduces suicide risk, but it is unclear whether this protective effect persists in modern, more secular societies.

Aims: To examine suicide risk according to Christian religious affiliation and by inference to examine underlying mechanisms for suicide risk. If church attendance is important, risk should be lowest for Roman Catholics and highest for those with no religion; if religiosity is important, then ‘conservative’ Christians should fare best.

Method: A 9-year study followed 1 106 104 people aged 16–74 years at the 2001 UK census, using Cox proportional hazards models adjusted for census-based cohort attributes.

Results: In fully adjusted models analysing 1119 cases of suicide, Roman Catholics, Protestants and those professing no religion recorded similar risks. The risk associated with conservative Christians was lower than that for Catholics (HR = 0.71, 95% CI 0.52–0.97).

Conclusions: The relationship between religious affiliation and suicide established by Durkheim may not pertain in societies where suicide rates are highest at younger ages. Risks are similar for those with and without a religious affiliation, and Catholics (who traditionally are characterised by higher levels of church attendance) do not demonstrate lower risk of suicide. However, religious affiliation is a poor measure of religiosity, except for a small group of conservative Christians, although their lower risk of suicide may be attributable to factors such as lower risk behaviour and alcohol consumption.

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Performance evaluation of parallel software and architectural exploration of innovative hardware support face a common challenge with emerging manycore platforms: they are limited by the slow running time and the low accuracy of software simulators. Manycore FPGA prototypes are difficult to build, but they offer great rewards. Software running on such prototypes runs orders of magnitude faster than current simulators. Moreover, researchers gain significant architectural insight during the modeling process. We use the Formic FPGA prototyping board [1], which specifically targets scalable and cost-efficient multi-board prototyping, to build and test a 64-board model of a 512-core, MicroBlaze-based, non-coherent hardware prototype with a full network-on-chip in a 3D-mesh topology. We expand the hardware architecture to include the ARM Versatile Express platforms and build a 520-core heterogeneous prototype of 8 Cortex-A9 cores and 512 MicroBlaze cores. We then develop an MPI library for the prototype and evaluate it extensively using several bare-metal and MPI benchmarks. We find that our processor prototype is highly scalable, models faithfully single-chip multicore architectures, and is a very efficient platform for parallel programming research, being 50,000 times faster than software simulation.

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The fate of missing persons is a central issue in post-conflict societies facing truth recovery and human rights dilemmas. Despite widespread public sympathy towards relatives, societies emerging from conflict often defer the recovery of missing for decades. More paradoxically, in post-1974 Cyprus, the official authorities delayed unilateral exhumations of victims buried within cemeteries in their own jurisdiction. Analysis of official post-1974 discourse reveals a Greek-Cypriot consensus to emphasise the issue as one of Turkish aggression, thus downplaying in-group responsibilities and the legacy of intra-communal violence. We compare the experience of Cyprus with other post-conflict societies such as Spain, Northern Ireland, and Mozambique and explore the linkages between institutions and beliefs about transitional justice. We argue that elite consensus initiates and facilitates the transition to democracy but often leads to the institutionalization of groups opposing truth recovery even for in-group members.

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Oxytocin (OT) influences how humans process information about others. Whether OT affects the processing of information about oneself remains unknown. Using a double-blind, placebo-controlled within-subject design, we recorded event-related potentials (ERPs) from adults during trait judgments about oneself and a celebrity and during judgments on word valence, after intranasal OT or placebo administration. We found that OT vs. placebo treatment reduced the differential amplitudes of a fronto-central positivity at 220-280 ms (P2) during self- vs. valence-judgments. OT vs. placebo treatment tended to reduce the differential amplitude of a late positive potential at 520-1000 ms (LPP) during self-judgments but to increase the differential LPP amplitude during other-judgments. OT effects on the differential P2 and LPP amplitudes to self- vs. celebrity-judgments were positively correlated with a measure of interdependence of self-construals. Thus OT modulates the neural correlates of self-referential processing and this effect varies as a function of interdependence.

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OBJECTIVES: Results from studies examining the association between alcohol consumption and the risk of Barrett's esophagus have been inconsistent. We assessed the risk of Barrett's esophagus associated with total and beverage-specific alcohol consumption by pooling individual participant data from five case–control studies participating in the international Barrett's and Esophageal Adenocarcinoma Consortium.
METHODS: For analysis, there were 1,282 population-based controls, 1,418 controls with gastroesophageal reflux disease (GERD), and 1,169 patients with Barrett's esophagus (cases). We estimated study-specific odds ratios (ORs) and 95% confidence intervals (95% CI) using multivariable logistic regression models adjusted for age, sex, body mass index (BMI), education, smoking status, and GERD symptoms. Summary risk estimates were obtained by random-effects models. We also examined potential effect modification by sex, BMI, GERD symptoms, and cigarette smoking.
RESULTS: For comparisons with population-based controls, although there was a borderline statistically significant inverse association between any alcohol consumption and the risk of Barrett's esophagus (any vs. none, summary OR=0.77, 95% CI=0.60–1.00), risk did not decrease in a dose-response manner (Ptrend=0.72). Among alcohol types, wine was associated with a moderately reduced risk of Barrett's esophagus (any vs. none, OR=0.71, 95% CI=0.52–0.98); however, there was no consistent dose–response relationship (Ptrend=0.21). We found no association with alcohol consumption when cases were compared with GERD controls. Similar associations were observed across all strata of BMI, GERD symptoms, and cigarette smoking.
CONCLUSIONS: Consistent with findings for esophageal adenocarcinoma, we found no evidence that alcohol consumption increases the risk of Barrett's esophagus.

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X-ray and radio observations of the supernova remnant Cassiopeia A reveal the presence of magnetic fields about 100 times stronger than those in the surrounding interstellar medium. Field coincident with the outer shock probably arises through a nonlinear feedback process involving cosmic rays. The origin of the large magnetic field in the interior of the remnant is less clear but it is presumably stretched and amplified by turbulent motions. Turbulence may be generated by hydrodynamic instability at the contact discontinuity between the supernova ejecta and the circumstellar gas9. However, optical observations of Cassiopeia A indicate that the ejecta are interacting with a highly inhomogeneous, dense circumstellar cloud bank formed before the supernova explosion. Here we investigate the possibility that turbulent amplification is induced when the outer shock overtakes dense clumps in the ambient medium. We report laboratory experiments that indicate the magnetic field is amplified when the shock interacts with a plastic grid. We show that our experimental results can explain the observed synchrotron emission in the interior of the remnant. The experiment also provides a laboratory example of magnetic field amplification by turbulence in plasmas, a physical process thought to occur in many astrophysical phenomena.