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Value clashes, power competition and community trust: why an NGO's earthquake recovery program faltered in rural China
The association between herd- and cow-level factors and somatic cell count of Irish dairy cows
peer-reviewedSomatic cell count (SCC) is an indicator of both udder health and milk quality and is
measured at an animal level through national milk recording schemes. The objective
of this study was to assess the animal and herd factors contributing to elevated SCC
(i.e. poorer milk quality). Test day records (n = 2,658,928) from 519,456 cow lactations
obtained between 2007 and 2011 were included in the analyses. Herd factors tested
included the geographical region of the herd and production system operated (spring
calving or mixed calving system). Animal factors tested included breed, parity and
age nested within parity. Four definitions of normalised SCC (i.e. SCS) were considered:
1) average test-day SCS within a 24 hour period (TD_SCS), 2) maximum SCS (peak_SCS), 3) minimum SCS (min_SCS), and 4) average SCS (avg_SCS) recorded across cow lactation; in addition, the proportion of test day records with an SCC count >200,000 (prop_200) or >250,000 (prop_250) within cow lactation were included. Following adjustment for fixed effects, average TD_SCS was 179,308 cells per mL while avg_SCS, and average min_SCS and peak_SCS were 119,481, 50,992 and 298,813 cells per mL, respectively. All animal and herd factors had a significant effect on SCC. Older animals, animals which were younger at calving than contemporaries and Holstein animals had higher SCC than younger alternative breed animals who calved at the median age. In addition, mixed calving production systems and herds in Connaught had higher SCC than spring calving herds in the other regions of Ireland.The authors gratefully acknowledge funding for this work from the Department of Agriculture, Fisheries and Food under the Joint FIRM / RSF Initiative (Project Number: 10/RD/AAQUALITYMILK/
TMFRC713)
The entanglement beam splitter: a quantum-dot spin in a double-sided optical microcavity
We propose an entanglement beam splitter (EBS) using a quantum-dot spin in a
double-sided optical microcavity. In contrast to the conventional optical beam
splitter, the EBS can directly split a photon-spin product state into two
constituent entangled states via transmission and reflection with high fidelity
and high efficiency (up to 100 percent). This device is based on giant optical
circular birefringence induced by a single spin as a result of cavity quantum
electrodynamics and the spin selection rule of trion transition (Pauli
blocking). The EBS is robust and it is immune to the fine structure splitting
in a realistic quantum dot. This quantum device can be used for
deterministically creating photon-spin, photon-photon and spin-spin
entanglement as well as a single-shot quantum non-demolition measurement of a
single spin. Therefore, the EBS can find wide applications in quantum
information science and technology.Comment: 7 pages, 5 figure
Impaired perception of facial motion in autism spectrum disorder
Copyright: © 2014 O’Brien et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.This article has been made available through the Brunel Open Access Publishing Fund.Facial motion is a special type of biological motion that transmits cues for socio-emotional communication and enables the discrimination of properties such as gender and identity. We used animated average faces to examine the ability of adults with autism spectrum disorders (ASD) to perceive facial motion. Participants completed increasingly difficult tasks involving the discrimination of (1) sequences of facial motion, (2) the identity of individuals based on their facial motion and (3) the gender of individuals. Stimuli were presented in both upright and upside-down orientations to test for the difference in inversion effects often found when comparing ASD with controls in face perception. The ASD group’s performance was impaired relative to the control group in all three tasks and unlike the control group, the individuals with ASD failed to show an inversion effect. These results point to a deficit in facial biological motion processing in people with autism, which we suggest is linked to deficits in lower level motion processing we have previously reported
Structures Produced by the Collision of Extragalactic Jets with Dense Clouds
We have investigated how several parameters can affect the results of a
collision between an extragalactic jet and a dense, intergalactic cloud,
through a series of hydrodynamic simulations. Such collisions are often
suggested to explain the distorted structures of some radio jets. However,
theoretical studies of this mechanism are in conflict over whether it can
actually reproduce the observations.
The parameters are the Mach number, and the relative densities of the jet and
the cloud to the ambient medium. Using a simple prescription we have produced
synthetic radio images for comparison with observations. These show that a
variety of structures may be produced from simple jet-cloud collisions. We
illustrate this with a few examples, and examine the details in one case. In
most cases we do not see a clear, sustained deflection. Lighter jets are
completely disrupted. The most powerful jets produce a hotspot at the impact
which outshines any jet emission and erode the cloud too quickly to develop a
deflected arm. It appears that moderate Mach numbers and density contrasts are
needed to produce bends in the radio structure. This explains the apparent
conflict between theoretical studies, as conclusions were based on different
values of these parameters. Shocks are produced in the ambient medium that
might plausibly reproduce the observed alignment of the extended emission line
regions with the radio axis.Comment: 21 pages, 11 figures. Submitted to MNRAS. Also available in html
version at http://www.doc.mmu.ac.uk/STAFF/S.Higgins/jcmnpaper/jc_mn.htm
Optical Quantum Computing
In 2001 all-optical quantum computing became feasible with the discovery that
scalable quantum computing is possible using only single photon sources, linear
optical elements, and single photon detectors. Although it was in principle
scalable, the massive resource overhead made the scheme practically daunting.
However, several simplifications were followed by proof-of-principle
demonstrations, and recent approaches based on cluster states or error encoding
have dramatically reduced this worrying resource overhead, making an
all-optical architecture a serious contender for the ultimate goal of a
large-scale quantum computer. Key challenges will be the realization of
high-efficiency sources of indistinguishable single photons, low-loss, scalable
optical circuits, high efficiency single photon detectors, and low-loss
interfacing of these components.Comment: 5 pages, 4 figure
Aerosol-assisted metallo-organic chemical vapour deposition of Bi2Se3 films using single-molecule precursors: the crystal structure of bismuth(m) dibutyldiselenocarbamate
The complexes [Bi{Se2CN(C2H5)2}3], [Bi{Se2CN(C4H9)2}3], [Bi{Se2CN(CH3)(C4H9)}3] and
[Bi{Se2CN(CH3)(C6H13)}3] have been synthesized and characterized structurally using IR, 1H and 13C NMR. In
addition, the crystal structure of [Bi{Se2CN(C4H9)2}3] was determined by single-crystal X-ray diffraction,
showing the bismuth centre coordinated to three dialkyldiselenocarbamate ligands through the selenium donor
atoms. The Bi(III) compounds were used as precursors for the deposition of Bi2Se3 films on glass substrates
through aerosol-assisted metallo-organic chemical vapour deposition (AA-MOCVD)
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