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Hendra virus (HeV) continues to cause fatal infection in horses and threaten infection in close-contact humans in eastern Australia. Species of Pteropus bats (flying-foxes) are the natural reservoir of the virus. We caught and sampled flying-foxes from a multispecies roost in southeast Queensland, Australia on eight occasions between June 2013 and June 2014. The effects of sample date, species, sex, age class, body condition score (BCS), pregnancy and lactation on HeV antibody prevalence, log-transformed median fluorescent intensity (lnMFI) values and HeV RNA status were assessed using unbalanced generalised linear models. A total of 1968 flying-foxes were sampled, comprising 1012 Pteropus alecto, 742 P. poliocephalus and 214 P. scapulatus. Sample date, species and age class were each statistically associated with HeV RNA status, antibody status and lnMFI values; BCS was statistically associated with HeV RNA status and antibody status. The findings support immunologically naïve sub-adult P. alecto playing an important role in maintaining HeV infection at a population level. The biological significance of the association between BCS and HeV RNA status, and BCS and HeV antibody status, is less clear and warrants further investigation. Contrary to previous studies, we found no direct association between HeV infection and pregnancy or lactation. The findings in P. poliocephalus suggest that HeV exposure in this species may not result in systemic infection and virus excretion, or alternatively, may reflect assay cross-reactivity with another (unidentified) henipavirus.
The Numeniini is a tribe of 13 wader species (Scolopacidae, Charadriiformes) of which seven are Near Threatened or globally threatened, including two Critically Endangered. To help inform conservation management and policy responses, we present the results of an expert assessment of the threats that members of this taxonomic group face across migratory flyways. Most threats are increasing in intensity, particularly in non-breeding areas, where habitat loss resulting from residential and commercial development, aquaculture, mining, transport, disturbance, problematic invasive species, pollution and climate change were regarded as having the greatest detrimental impact. Fewer threats (mining, disturbance, problematic native species and climate change) were identified as widely affecting breeding areas. Numeniini populations face the greatest number of non-breeding threats in the East Asian-Australasian Flyway, especially those associated with coastal reclamation; related threats were also identified across the Central and Atlantic Americas, and East Atlantic flyways. Threats on the breeding grounds were greatest in Central and Atlantic Americas, East Atlantic and West Asian flyways. Three priority actions were associated with monitoring and research: to monitor breeding population trends (which for species breeding in remote areas may best be achieved through surveys at key non-breeding sites), to deploy tracking technologies to identify migratory connectivity, and to monitor land-cover change across breeding and non-breeding areas. Two priority actions were focused on conservation and policy responses: to identify and effectively protect key non-breeding sites across all flyways (particularly in the East Asian- Australasian Flyway), and to implement successful conservation interventions at a sufficient scale across human-dominated landscapes for species’ recovery to be achieved. If implemented urgently, these measures in combination have the potential to alter the current population declines of many Numeniini species and provide a template for the conservation of other groups of threatened species.
Among dialysis facilities participating in a bloodstream infection (BSI) prevention collaborative, access-related BSI incidence rate improvements observed immediately following implementation of a bundle of BSI prevention interventions were sustained for up to 4 years. Overall, BSI incidence remained unchanged from baseline in the current analysis.
The advantages of in-situ SIMS plasma probe diagnostics are highlighted in low pressure hydrocarbon ECR reactive ion etching (RIE) of III-V materials. Three aspects of the RIE process are investigated. First, the dominant ion species in a CH4/H2/Ar plasma are recorded at various chamber pressures, ECR powers, CH4/(CH4+H2) gas flow ratios and microwave cavity tuning. These studies have improved our understanding of the effects of these parameters on the relative concentrations of reactive precursor species in the plasma and have led to more rapid optimization of the etch system. Secondly, SIMS has been used for identification of reaction products from the III-V surface at the optimized plasma conditions. The Ar diluted mixture gives rise to significant levels of group V hydrides and organometallic compounds and the dominant group III volatile ions have been positively identified as dimethyl species. The third and final aspect reported is the application of volatile product identification to endpoint detection. In lcm2 multiple quantum well samples, layers as thin as 50Å are easily distinguishable.
Space-time interaction analysis was applied to data from 101 elementary school children who contracted variola minor during an epidemic in Bragança Paulista County, Brazil. One school had two and the other three shifts of students occupying the same classrooms each day. There was no evidence found for excessive numbers of cases to occur among unvaccinated students occupying the same desks or seated near the desks occupied by cases occurring during another shift. Only three cases occurred among the 31 unvaccinated students occupying desks of students with variola from other shifts. Only one of these three subsequent cases occurred at a time interval suggestive of transmission. For the three models tested there was no evidence of space-time interaction between time of onset of the disease and location of desk for pairs of students from different shifts.
Timm et al. (2001) argue that Pseudonovibos spiralis actually exists as a new bovine species, and identify as such two frontlets in the Kansas Natural History Museum, U.S.A. This is not the first time these specimens have been the subject of dubious taxonomic identification; they were previously misidentified by Hoffman (1986) as female kouprey Bos sauveli. A further irony is that the original unmasking (Dioli, 1995) was accomplished by an author of the current defense.
Digital particle image velocimetry (DPIV) measurements of the velocity field under
breaking waves in the laboratory are presented. The region of turbulent fluid directly
generated by breaking is too large to be imaged in one video frame and so an
ensemble-averaged representation of the flow is built up from a mosaic of image
frames. It is found that breaking generates at least one coherent vortex that slowly
propagates downstream at a speed consistent with the velocity induced by its image
in the free surface. Both the kinetic energy of the flow and the vorticity decay
approximately as t−1. The Reynolds stress of the turbulence also decays as t−1 and
is, within the accuracy of the measurements, everywhere negative, consistent with
downward transport of streamwise momentum. Estimates of the mometum flux from
waves to currents based on the measurements of the Reynolds stress are consistent
with earlier estimates. The implications of the measurements for breaking in the
field are discussed. Based on geometrical optics and wave action conservation, we
suggest that the presence of the breaking-induced vortex provides an explanation for
the suppression of short waves by breaking. Finally, in Appendices, estimates of the
majority of the terms in the turbulent kinetic energy budget are presented at an early
stage in the evolution of the turbulence, and comparisons with independent acoustical
measurements of breaking are presented.
Needles of Pinus strobus (white pine) were cleared and stained to survey the occurrence and location of Lophodermium sp., a fungal endophyte. Cytoplasmically dense endophytic hyphae with a pronounced lobed morphology and containing lipid bodies were localized intercellularly between the epidermis and hypodermis. These fungal infections did not appear quiescent, but rather exhibited signs of continual slow growth. A few associated host cells exhibited a hypersensitive response. Material embedded in resin and examined by light microscopy and transmission electron microscopy confirmed the location of hyphae between epidermal and hypodermal cells, and the presence of lipid bodies within the hyphae. In senescing needles, aggressive colonization of needle tissues occurred. Thus, for Lophodermium in white pine, endophytic infection is active rather than quiescent, and displays an alternate hyphal strategy to that seen in the reproductive phase.
We show that a quantum Verma-type module for a quantum group associated to an affine Kac-Moody algebra is characterized by its subspace of finite-dimensional weight spaces. In order to do this we prove an explicit equivalence of categories between a certain category containing the quantum Verma modules and a category of modules for a subalgebra of the quantum group for which the finite part of the Verma module is itself a module.
The three trypanosomatid genome projects have employed common strategies which include: analysis of pulsed-field gel
electrophoretic chromosomal karyotypes; physical mapping using big DNA (cosmid, pacmid P1, bacterial artificial
chromosome, yeast artificial chromosome) libraries; partial cDNA sequence analysis to develop sets of expressed sequence
tags (ESTs) for gene discovery and use as markers in physical mapping; genomic sequencing; dissemination of information
through development of web-sites and ACeDB-based fully integrated databases; and establishment of functional genomics
programmes to maximize useful application of genome data. Highlights of the projects to date have been the demonstration
that, despite extensive chromosomal size polymorphisms for diploid homologues within Africa trypanosomes, T. cruzi or
Leishmania, the physical linkage groups for markers on each chromosome are retained across all isolates/species studied
within each group. For African trypanosomes, detailed analysis of chromosome 1 has demonstrated that repetitive
sequences and the two retroposon-like elements RIME and INGI are localized to a defined region at one end of the
chromosome, with the bulk of the central region of the chromosome containing genes coding for expressed proteins.
Comparative mapping shows that, although subtelomeric changes account for a large proportion of the polymorphism in
chromosome size in African trypanosomes, there are significant expansions and contractions in regions across the entire
chromosome. The highlight of the genomic sequencing projects has been the demonstration of just 2 putative transcriptional
units of chromosome 1 of Leishmania major, extending on opposite strands from a point in the central region
of the chromosome. A similar observation made on 93·4 kb of contiguous sequence for T. cruzi chromosome 3 suggests
the presence of promoter and regulatory elements at the junctions of large polycistronic transcriptional units. All data
obtained from the genome projects are made available through the public domain, which has prompted changing
philosophies in how we approach analysis of the biology of these organisms, and strategies that we can employ now in the
search for new therapies and vaccines.
We construct quantum deformations of imaginary Verma modules over $U(A_1^{(1)})$ and show that, for generic $q$, imaginary Verma modules over $U(A_1^{(1)})$ can be deformed to those over the quantum group $U_q(A_1^{(1)})$ in such a way that the dimensions of the weight spaces are invariant under the deformation. We also prove the PBW theorem for $U_q(A_1^{(1)})$ with respect to the triangular
decomposition induced from the root partition corresponding to the
imaginary Verma modules.
Affine Kac-Moody algebras represent a well-trodden and well-understood littoral beyond which stretches the vast, chaotic, and poorly-understood ocean of indefinite Kac-Moody algebras. The simplest indefinite Kac-Moody algebras are the rank 2 Kac-Moody algebras (a) (a ≥ 3) with symmetric Cartan matrix , which form part of the class known as hyperbolic Kac-Moody algebras. In this paper, we probe deeply into the structure of those algebras (a), the e. coli of indefinite Kac-Moody algebras. Using Berman-Moody’s formula ([BM]), we derive a purely combinatorial closed form formula for the root multiplicities of the algebra (a), and illustrate some of the rich relationships that exist among root multiplicities, both within a single algebra and between different algebras in the class. We also give an explicit description of the root system of the algebra (a). As a by-product, we obtain a simple algorithm to find the integral points on certain hyperbolas.
A large range of tracheostomy tube types and sizes are available for use in children. Regional preference, rather than individual patient assessment, tends to determine selection. We present a table designed to assist with appropriate size selection, and discuss the relative merits and shortcomings of the tubes currently available.