1,405 research outputs found
Exocytosis of acid sphingomyelinase by wounded cells promotes endocytosis and plasma membrane repair
Lysosomal enzyme acid sphingomyelinase is released extracellularly when cells are wounded, converting sphingomyelin to ceramide and inducing endosome formation to internalize membrane lesions
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High-K dielectric sulfur-selenium alloys.
Upcoming advancements in flexible technology require mechanically compliant dielectric materials. Current dielectrics have either high dielectric constant, K (e.g., metal oxides) or good flexibility (e.g., polymers). Here, we achieve a golden mean of these properties and obtain a lightweight, viscoelastic, high-K dielectric material by combining two nonpolar, brittle constituents, namely, sulfur (S) and selenium (Se). This S-Se alloy retains polymer-like mechanical flexibility along with a dielectric strength (40 kV/mm) and a high dielectric constant (K = 74 at 1 MHz) similar to those of established metal oxides. Our theoretical model suggests that the principal reason is the strong dipole moment generated due to the unique structural orientation between S and Se atoms. The S-Se alloys can bridge the chasm between mechanically soft and high-K dielectric materials toward several flexible device applications
Anisotropic Coarsening: Grain Shapes and Nonuniversal Persistence
We solve a coarsening system with small but arbitrary anisotropic surface
tension and interface mobility. The resulting size-dependent growth shapes are
significantly different from equilibrium microcrystallites, and have a
distribution of grain sizes different from isotropic theories. As an
application of our results, we show that the persistence decay exponent depends
on anisotropy and hence is nonuniversal.Comment: 4 pages (revtex), 2 eps figure
Increased risk of A(H1N1)pdm09 influenza infection in UK pig industry workers compared to a general population cohort
Background: Pigs are mixing vessels for influenza viral reassortment but the extent of influenza transmission between swine and humans is not well understood.
Objectives: To assess whether occupational exposure to pigs is a risk factor for human infection with human and swine-adapted influenza viruses.
Methods: UK pig industry workers were frequency-matched on age, region, sampling month, and gender with a community-based comparison group from the Flu Watch study. HI assays quantified antibodies for swine and human A(H1) and A(H3) influenza viruses (titres≥40 considered seropositive and indicative of infection). Virus-specific associations between seropositivity and occupational pig exposure were examined using multivariable regression models adjusted for vaccination. Pigs on the same farms were also tested for seropositivity.
Results: 42% of pigs were seropositive to A(H1N1)pdm09. Pig industry workers showed evidence of increased odds of A(H1N1)pdm09 seropositivity compared to the comparison group, albeit with wide confidence intervals (CI), Adjusted Odds Ratio after accounting for possible cross reactivity with other swine A(H1) viruses (aOR) 25.30, 95% CI [1.44-536.34], p=0.028.
Conclusion: The results indicate that A(H1N1)pdm09 virus was common in UK pigs during the pandemic and subsequent period of human A(H1N1)pdm09 circulation, and occupational exposure to pigs was a risk factor for human infection. Influenza immunization of pig industry workers may reduce transmission and the potential for virus reassortment
Facial expression recognition in dynamic sequences: An integrated approach
Automatic facial expression analysis aims to analyse human facial expressions and classify them into discrete categories. Methods based on existing
work are reliant on extracting information from video sequences and employ either some form of subjective thresholding of dynamic information or
attempt to identify the particular individual frames in which the expected
behaviour occurs. These methods are inefficient as they require either additional subjective information, tedious manual work or fail to take advantage
of the information contained in the dynamic signature from facial movements
for the task of expression recognition.
In this paper, a novel framework is proposed for automatic facial expression analysis which extracts salient information from video sequences
but does not rely on any subjective preprocessing or additional user-supplied
information to select frames with peak expressions. The experimental framework demonstrates that the proposed method outperforms static expression
recognition systems in terms of recognition rate. The approach does not rely on action units (AUs) and therefore, eliminates errors which are otherwise
propagated to the final result due to incorrect initial identification of AUs.
The proposed framework explores a parametric space of over 300 dimensions
and is tested with six state-of-the-art machine learning techniques. Such
robust and extensive experimentation provides an important foundation for
the assessment of the performance for future work. A further contribution
of the paper is offered in the form of a user study. This was conducted in
order to investigate the correlation between human cognitive systems and the
proposed framework for the understanding of human emotion classification
and the reliability of public databases
Increased risk of A(H1N1)pdm09 influenza infection in UK pig industry workers compared to a general population cohort.
BACKGROUND: Pigs are mixing vessels for influenza viral reassortment, but the extent of influenza transmission between swine and humans is not well understood. OBJECTIVES: To assess whether occupational exposure to pigs is a risk factor for human infection with human and swine-adapted influenza viruses. METHODS: UK pig industry workers were frequency-matched on age, region, sampling month, and gender with a community-based comparison group from the Flu Watch study. HI assays quantified antibodies for swine and human A(H1) and A(H3) influenza viruses (titres ≥ 40 considered seropositive and indicative of infection). Virus-specific associations between seropositivity and occupational pig exposure were examined using multivariable regression models adjusted for vaccination. Pigs on the same farms were also tested for seropositivity. RESULTS: Forty-two percent of pigs were seropositive to A(H1N1)pdm09. Pig industry workers showed evidence of increased odds of A(H1N1)pdm09 seropositivity compared to the comparison group, albeit with wide confidence intervals (CIs), adjusted odds ratio after accounting for possible cross-reactivity with other swine A(H1) viruses (aOR) 25·3, 95% CI (1·4-536·3), P = 0·028. CONCLUSION: The results indicate that A(H1N1)pdm09 virus was common in UK pigs during the pandemic and subsequent period of human A(H1N1)pdm09 circulation, and occupational exposure to pigs was a risk factor for human infection. Influenza immunisation of pig industry workers may reduce transmission and the potential for virus reassortment.This work was supported by joint funding from the
Biotechnology and Biological Sciences Research Council
(BBSRC), the Medical Research Council (MRC), and the
Wellcome Trust (WT) [(BBSRC/MRC/WT) BB/H014306/1;
(MRC/WT) MC_U122785833; (MRC) G0800767 and
G0600511]; Alborada Trust (to J.L.N.W.); the RAPIDD
programme of the Science & Technology Directorate (to
J.L.N.W.); US Department of Homeland Security (to
J.L.N.W.); and the Fogarty International Center at the
National Institutes of Health (to J.L.N.W.). DAI is supported
by a fellowship from the National Institute for Health
Research (NIHR) (PDF-2012-05-305) (this research is independent
and the views expressed in this publication are those
of the authors and not necessarily those of the Department of
Health or NIHR).This is the final version of the article. It first appeared from Wiley via https://doi.org//10.1111/irv.12364/abstract
Cohort Profile: The Flu Watch Study
Influenza is a common, highly contagious respiratory virus which infects all age groups, causing a range of outcomes from asymptomatic infection and mild respiratory disease to severe respiratory disease and death.1 If infected, the adaptive immune system produces a humoral (antibody) and cell-mediated (T cell) immune response to fight the infection.2 Influenza viruses continually evolve through antigenic drift, resulting in slightly different ‘seasonal’ influenza strains circulating each year. Population-level antibody immunity to these seasonal viruses builds up over time, so in any given season only a proportion of the population is susceptible to the circulating strains. Occasionally, influenza A viruses evolve rapidly through antigenic shift by swapping genes with influenza viruses usually circulating in animals. This process creates an immunologically distinct virus to which the population may have little to no antibody immunity. The virus can result in a pandemic if a large portion of the population is susceptible and the virus is easily spread
TESS Discovery of a Transiting Super-Earth in the Mensae System
We report the detection of a transiting planet around Mensae (HD
39091), using data from the Transiting Exoplanet Survey Satellite (TESS). The
solar-type host star is unusually bright (V=5.7) and was already known to host
a Jovian planet on a highly eccentric, 5.7-year orbit. The newly discovered
planet has a size of and an orbital period of 6.27
days. Radial-velocity data from the HARPS and AAT/UCLES archives also displays
a 6.27-day periodicity, confirming the existence of the planet and leading to a
mass determination of . The star's proximity and
brightness will facilitate further investigations, such as atmospheric
spectroscopy, asteroseismology, the Rossiter--McLaughlin effect, astrometry,
and direct imaging.Comment: Accepted for publication ApJ Letters. This letter makes use of the
TESS Alert data, which is currently in a beta test phase. The discovery light
curve is included in a table inside the arxiv submissio
Trypanosoma cruzi subverts the sphingomyelinase-mediated plasma membrane repair pathway for cell invasion
Trypanosoma cruzi takes advantage of a sphingomyelinase-dependent plasma membrane repair pathway to gain access to host cells
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