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The resolution sensitivity of the Asian summer monsoon and its inter-model comparison between MRI-AGCM and MetUM
In this study, we compare the resolution sensitivity of the Asian Summer Monsoon (ASM) in two Atmospheric General Circulation Models (AGCMs): the MRI-AGCM and the MetUM. We analyze the MetUM at three different resolutions, N96 (approximately 200-km mesh on the equator), N216 (90-km mesh) and N512 (40-km mesh), and the MRI-AGCM at TL95 (approximately 180-km mesh on the equator), TL319 (60-km mesh), and TL959 (20-km mesh). The MRI-AGCM and the MetUM both show decreasing precipitation over the western Pacific with increasing resolution, but their precipitation responses differ over the Indian Ocean. In MRI-AGCM, a large precipitation increase appears off the equator (5–20°N). In MetUM, this off-equatorial precipitation increase is less significant and precipitation decreases over the equator. Moisture budget analysis demonstrates that a changing in moisture flux convergence at higher resolution is related to the precipitation response. Orographic effects, intra-seasonal variability and the representation of the meridional thermal gradient are explored as possible causes of the resolution sensitivity. Both high-resolution AGCMs (TL959 and N512) can represent steep topography, which anchors the rainfall pattern over south Asia and the Maritime Continent. In MRI-AGCM, representation of low pressure systems in TL959 also contributes to the rainfall pattern. Furthermore, the seasonal evolution of the meridional thermal gradient appears to be more accurate at higher resolution, particularly in the MRI-AGCM. These findings emphasize that the impact of resolution is only robust across the two AGCMs for some features of the ASM, and highlights the importance of multi-model studies of GCM resolution sensitivity
Abundance of the Quorum-Sensing Factor Ax21 in Four Strains of Stenotrophomonas maltophilia Correlates with Mortality Rate in a New Zebrafish Model of Infection
Stenotrophomonas maltophilia is a Gram-negative pathogen with emerging nosocomial incidence. Little is known about its pathogenesis and the genomic diversity exhibited by clinical isolates complicates the study of pathogenicity and virulence factors. Here, we present a strategy to identify such factors in new clinical isolates of S. maltophilia, incorporating an adult-zebrafish model of S. maltophilia infection to evaluate relative virulence coupled to 2D difference gel electrophoresis to explore underlying differences in protein expression. In this study we report upon three recent clinical isolates and use the collection strain ATCC13637 as a reference. The adult-zebrafish model shows discrimination capacity, i.e. from very low to very high mortality rates, with clinical symptoms very similar to those observed in natural S. maltophilia infections in fish. Strain virulence correlates with resistance to human serum, in agreement with previous studies in mouse and rat and therefore supporting zebrafish as a replacement model. Despite its clinical origin, the collection strain ATCC13637 showed obvious signs of attenuation in zebrafish, with null mortality. Multilocus-sequence-typing analysis revealed that the most virulent strains, UV74 and M30, exhibit the strongest genetic similitude. Differential proteomic analysis led to the identification of 38 proteins with significantly different abundance in the three clinical strains relative to the reference strain. Orthologs of several of these proteins have been already reported to have a role in pathogenesis, virulence or resistance mechanisms thus supporting our strategy. Proof of concept is further provided by protein Ax21, whose abundance is shown here to be directly proportional to mortality in the zebrafish infection model. Indeed, recent studies have demonstrated that this protein is a quorum-sensing-related virulence factor
Operation and performance of the ATLAS Tile Calorimeter in Run 1
The Tile Calorimeter is the hadron calorimeter covering the central region of the ATLAS experiment at the Large Hadron Collider. Approximately 10,000 photomultipliers collect light from scintillating tiles acting as the active material sandwiched between slabs of steel absorber. This paper gives an overview of the calorimeter’s performance during the years 2008–2012 using cosmic-ray muon events and proton–proton collision data at centre-of-mass energies of 7 and 8TeV with a total integrated luminosity of nearly 30 fb−1. The signal reconstruction methods, calibration systems as well as the detector operation status are presented. The energy and time calibration methods performed excellently, resulting in good stability of the calorimeter response under varying conditions during the LHC Run 1. Finally, the Tile Calorimeter response to isolated muons and hadrons as well as to jets from proton–proton collisions is presented. The results demonstrate excellent performance in accord with specifications mentioned in the Technical Design Report
MRPS18CP2 alleles and DEFA3 absence as putative chromosome 8p23.1 modifiers of hearing loss due to mtDNA mutation A1555G in the 12S rRNA gene
<p>Abstract</p> <p>Background</p> <p>Mitochondrial DNA (mtDNA) mutations account for at least 5% of cases of postlingual, nonsyndromic hearing impairment. Among them, mutation A1555G is frequently found associated with aminoglycoside-induced and/or nonsyndromic hearing loss in families presenting with extremely variable clinical phenotypes. Biochemical and genetic data have suggested that nuclear background is the main factor involved in modulating the phenotypic expression of mutation A1555G. However, although a major nuclear modifying locus was located on chromosome 8p23.1 and regardless intensive screening of the region, the gene involved has not been identified.</p> <p>Methods</p> <p>With the aim to gain insights into the factors that determine the phenotypic expression of A1555G mutation, we have analysed in detail different genetic and genomic elements on 8p23.1 region (<it>DEFA3 </it>gene absence, <it>CLDN23 </it>gene and <it>MRPS18CP2 </it>pseudogene) in a group of 213 A1555G carriers.</p> <p>Results</p> <p>Family based association studies identified a positive association for a polymorphism on <it>MRPS18CP2 </it>and an overrepresentation of <it>DEFA3 </it>gene absence in the deaf group of A1555G carriers.</p> <p>Conclusion</p> <p>Although none of the factors analysed seem to have a major contribution to the phenotype, our findings provide further evidences of the involvement of 8p23.1 region as a modifying locus for A1555G 12S rRNA gene mutation.</p
First serological evidence of West Nile virus in human rural populations of Gabon
To investigate West Nile virus (WNV) circulation in rural populations in Gabon, we undertook a large serological survey focusing on human rural populations, using two different ELISA assays. A sample was considered positive when it reacted in both tests. A total of 2320 villagers from 115 villages were interviewed and sampled. Surprisingly, the WNV-specific IgG prevalence was high overall (27.2%) and varied according to the ecosystem: 23.7% in forested regions, 21.8% in savanna, and 64.9% in the lakes region. The WNV-specific IgG prevalence rate was 30% in males and 24.6% in females, and increased with age. Although serological cross-reactions between flaviviruses are likely and may be frequent, these findings strongly suggest that WNV is widespread in Gabon. The difference in WNV prevalence among ecosystems suggests preferential circulation in the lakes region. The linear increase with age suggests continuous exposure of Gabonese populations to WNV. Further investigations are needed to determine the WNV cycle and transmission patterns in Gabon
Local Sensitivity Analysis of Kinetic Models for Cellulose Pyrolysis
Abstract: The first and nth order kinetic models are usually used to describe cellulose pyrolysis. In this work, the local sensitivities of the conversion and derivative conversion with respect to the frequency factor, the logarithm of the frequency factor, the activation energy and the reaction order for the first and nth order kinetic models are calculated by using the finite difference method. The results show that the sensitivities of the first and nth order kinetic models with respect to the activation energy and the logarithm of the frequency factor are significant, while the frequency factor and the reaction order affect the nth order kinetic model slightly. Compared with the frequency factor, the natural logarithm of the frequency factor is a better choice in the parameter estimation of the first and nth order kinetic models. Graphical Abstract: [Figure not available: see fulltext.
Estimating Chikungunya prevalence in La Réunion Island outbreak by serosurveys: Two methods for two critical times of the epidemic
<p>Abstract</p> <p>Background</p> <p>Chikungunya virus (CHIKV) caused a major two-wave seventeen-month-long outbreak in La Réunion Island in 2005–2006. The aim of this study was to refine clinical estimates provided by a regional surveillance-system using a two-stage serological assessment as gold standard.</p> <p>Methods</p> <p>Two serosurveys were implemented: first, a rapid survey using stored sera of pregnant women, in order to assess the attack rate at the epidemic upsurge (s1, February 2006; n = 888); second, a population-based survey among a random sample of the community, to assess the herd immunity in the post-epidemic era (s2, October 2006; n = 2442). Sera were screened for anti-CHIKV specific antibodies (IgM and IgG in s1, IgG only in s2) using enzyme-linked immunosorbent assays. Seroprevalence rates were compared to clinical estimates of attack rates.</p> <p>Results</p> <p>In s1, 18.2% of the pregnant women were tested positive for CHIKV specific antibodies (13.8% for both IgM and IgG, 4.3% for IgM, 0.1% for IgG only) which provided a congruent estimate with the 16.5% attack rate calculated from the surveillance-system. In s2, the seroprevalence in community was estimated to 38.2% (95% CI, 35.9 to 40.6%). Extrapolations of seroprevalence rates led to estimate, at 143,000 and at 300,000 (95% CI, 283,000 to 320,000), the number of people infected in s1 and in s2, respectively. In comparison, the surveillance-system estimated at 130,000 and 266,000 the number of people infected for the same periods.</p> <p>Conclusion</p> <p>A rapid serosurvey in pregnant women can be helpful to assess the attack rate when large seroprevalence studies cannot be done. On the other hand, a population-based serosurvey is useful to refine the estimate when clinical diagnosis underestimates it. Our findings give valuable insights to assess the herd immunity along the course of epidemics.</p
Suicidality in primary care patients who present with sadness and anhedonia: a prospective European study
Background: Sadness and anhedonia (loss of interest in activities) are central symptoms of major depression.
However, not all people with these symptoms meet diagnostic criteria for major depression. We aimed to assess
the importance of suicidality in the outcomes for primary care patients who present with sadness and anhedonia.
Method: Cohort study of 2,599 unselected primary care attenders in six European countries followed up at 6 and
12 months.
Results: 1) In patients with sadness and/or anhedonia who were not depressed at entry to the study, suicide plans
(OR = 3.05; 95 % CI = 1.50–6.24; p = 0.0022) and suicide attempts (OR = 9.08; 95 % CI = 2.57–32.03; p = 0.0006) were
significant predictors of developing new onset depression at 6 or 12 months. 2) In patients with sadness and/or
anhedonia who met CIDI criteria for major depression at entry, suicidal ideation (OR = 2.93; 95 % CI = 1.70–5.07;
p = 0.0001), suicide plans (OR = 3.70; 95 % CI = 2.08–6.57; p < 0.0001), and suicide attempts (OR = 3.33; 95 %
CI = 1.47–7.54; p = 0.0040) were significant predictors of persistent depression at 6 or 12 months.
Conclusions: Three questions on suicidality could help primary care professionals to assess such patients more closely
without necessarily establishing whether they meet criteria for major depression.This research was funded by a grant from The European Commission,
referencePREDICT-QL4-CT2002-00683. We are also grateful for part support in
Europe from: the Estonian Scientific Foundation (grant number 5696); the
Slovenian Ministry for Research (grant No.4369-1027); the Spanish Ministry of
Health (grant FIS references: PI041980, PI041771, PI042450) and the Spanish
Network of Primary Care Research, redIAPP (ISCIII-RETICS RD06/0018) and
SAMSERAP group; and the UK NHS Research and Development office for
providing service support costs in the UK. We are also grateful for the support
from the University of Malaga (Spain) and to Carlos García from Loyola
Andalucía University (Spain)
The Evolution of Invasiveness in Garden Ants
It is unclear why some species become successful invaders whilst others fail, and whether invasive success depends on pre-adaptations already present in the native range or on characters evolving de-novo after introduction. Ants are among the worst invasive pests, with Lasius neglectus and its rapid spread through Europe and Asia as the most recent example of a pest ant that may become a global problem. Here, we present the first integrated study on behavior, morphology, population genetics, chemical recognition and parasite load of L. neglectus and its non-invasive sister species L. turcicus. We find that L. neglectus expresses the same supercolonial syndrome as other invasive ants, a social system that is characterized by mating without dispersal and large networks of cooperating nests rather than smaller mutually hostile colonies. We conclude that the invasive success of L. neglectus relies on a combination of parasite-release following introduction and pre-adaptations in mating system, body-size, queen number and recognition efficiency that evolved long before introduction. Our results challenge the notion that supercolonial organization is an inevitable consequence of low genetic variation for chemical recognition cues in small invasive founder populations. We infer that low variation and limited volatility in cuticular hydrocarbon profiles already existed in the native range in combination with low dispersal and a highly viscous population structure. Human transport to relatively disturbed urban areas thus became the decisive factor to induce parasite release, a well established general promoter of invasiveness in non-social animals and plants, but understudied in invasive social insects
Variation in Symbiodinium ITS2 Sequence Assemblages among Coral Colonies
Endosymbiotic dinoflagellates in the genus Symbiodinium are
fundamentally important to the biology of scleractinian corals, as well as to a
variety of other marine organisms. The genus Symbiodinium is
genetically and functionally diverse and the taxonomic nature of the union
between Symbiodinium and corals is implicated as a key trait
determining the environmental tolerance of the symbiosis. Surprisingly, the
question of how Symbiodinium diversity partitions within a
species across spatial scales of meters to kilometers has received little
attention, but is important to understanding the intrinsic biological scope of a
given coral population and adaptations to the local environment. Here we address
this gap by describing the Symbiodinium ITS2 sequence
assemblages recovered from colonies of the reef building coral Montipora
capitata sampled across Kāne'ohe Bay, Hawai'i. A
total of 52 corals were sampled in a nested design of Coral Colony(Site(Region))
reflecting spatial scales of meters to kilometers. A diversity of
Symbiodinium ITS2 sequences was recovered with the majority
of variance partitioning at the level of the Coral Colony. To confirm this
result, the Symbiodinium ITS2 sequence diversity in six
M. capitata colonies were analyzed in much greater depth
with 35 to 55 clones per colony. The ITS2 sequences and quantitative composition
recovered from these colonies varied significantly, indicating that each coral
hosted a different assemblage of Symbiodinium. The diversity of
Symbiodinium ITS2 sequence assemblages retrieved from
individual colonies of M. capitata here highlights the problems
inherent in interpreting multi-copy and intra-genomically variable molecular
markers, and serves as a context for discussing the utility and biological
relevance of assigning species names based on Symbiodinium ITS2
genotyping
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