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Dual isotopic composition of methane in Murchison meteorite
Dual isotopic composition (H and C) of methane extracted from a small sample of Murchison meteorite reveals a deuterium enrichment for this molecule, indicating the presence of interstellar hydrogen
Jet substructure as a new Higgs search channel at the LHC
It is widely considered that, for Higgs boson searches at the Large Hadron
Collider, WH and ZH production where the Higgs boson decays to b anti-b are
poor search channels due to large backgrounds. We show that at high transverse
momenta, employing state-of-the-art jet reconstruction and decomposition
techniques, these processes can be recovered as promising search channels for
the standard model Higgs boson around 120 GeV in mass.Comment: 4 pages, 3 figure
QUANTIFYING CRITICAL FEATURES OF UNDERWATER STROKE TECHNIQUE IN FREESTYLE SWIMMING
The purpose of this study was to establish methods for accurately quantifying the time of entry, catch and release in freestyle swimming. The methods allow ready data collection, digitising and analysis without recourse to expensive cameras and diglising equipment thereby enabling analysis by coaches as well as biomechanists. Interpolation procedures to improve the accuracy of estimating the time of occurrence of the events were developed
Photon Structure and Quantum Fluctuation
Photon structure derives from quantum fluctuation in quantum field theory to
fermion and anti-fermion, and has been an experimentally established feature of
electrodynamics since the discovery of the positron. In hadronic physics, the
observation of factorisable photon structure is similarly a fundamental test of
the quantum field theory Quantum Chromodynamics (QCD). An overview of
measurements of hadronic photon structure in e+e- and ep interactions is
presented, and comparison made with theoretical expectation, drawing on the
essential features of photon fluctuation into quark and anti-quark in QCD.Comment: 29 pages, 15 figures, to appear in Philosophical Transactions of the
Royal Society of London (Series A: Mathematical, Physical and Engineering
Sciences
Measurement of the neutron lifetime using a gravitational trap and a low-temperature Fomblin coating
We present a new value for the neutron lifetime of 878.5 +- 0.7 stat. +- 0.3
syst. This result differs from the world average value (885.7 +- 0.8 s) by 6.5
standard deviations and by 5.6 standard deviations from the previous most
precise result. However, this new value for the neutron lifetime together with
a beta-asymmetry in neutron decay, Ao, of -0.1189(7) is in a good agreement
with the Standard Model.Comment: 11 pages, 9 figures; extended content with some correction
Cellular and humoral immune responses and protection against schistosomes induced by a radiation-attenuated vaccine in chimpanzees
The radiation-attenuated Schistosoma mansoni vaccine is highly effective in rodents and primates but has never been tested in humans, primarily for safety reasons. To strengthen its status as a paradigm for a human recombinant antigen vaccine, we have undertaken a small-scale vaccination and challenge experiment in chimpanzees (Pan troglodytes). Immunological, clinical, and parasitological parameters were measured in three animals after multiple vaccinations, together with three controls, during the acute and chronic stages of challenge infection up to chemotherapeutic cure. Vaccination induced a strong in vitro proliferative response and early gamma interferon production, but type 2 cytokines were dominant by the time of challenge. The controls showed little response to challenge infection before the acute stage of the disease, initiated by egg deposition. In contrast, the responses of vaccinated animals were muted throughout the challenge period. Vaccination also induced parasite-specific immunoglobulin M (IgM) and IgG, which reached high levels at the time of challenge, while in control animals levels did not rise markedly before egg deposition. The protective effects of vaccination were manifested as an amelioration of acute disease and overall morbidity, revealed by differences in gamma-glutamyl transferase level, leukocytosis, eosinophilia, and hematocrit. Moreover, vaccinated chimpanzees had a 46% lower level of circulating cathodic antigen and a 38% reduction in fecal egg output, compared to controls, during the chronic phase of infection
Notes on the integration of numerical relativity waveforms
A primary goal of numerical relativity is to provide estimates of the wave
strain, , from strong gravitational wave sources, to be used in detector
templates. The simulations, however, typically measure waves in terms of the
Weyl curvature component, . Assuming Bondi gauge, transforming to the
strain reduces to integration of twice in time. Integrations
performed in either the time or frequency domain, however, lead to secular
non-linear drifts in the resulting strain . These non-linear drifts are not
explained by the two unknown integration constants which can at most result in
linear drifts. We identify a number of fundamental difficulties which can arise
from integrating finite length, discretely sampled and noisy data streams.
These issues are an artifact of post-processing data. They are independent of
the characteristics of the original simulation, such as gauge or numerical
method used. We suggest, however, a simple procedure for integrating numerical
waveforms in the frequency domain, which is effective at strongly reducing
spurious secular non-linear drifts in the resulting strain.Comment: 23 pages, 10 figures, matches final published versio
Frequency analysis of vocalisations in relation to the growth in broiler chicken
Poultry is one of the lowest cost sources of animal protein in the world and, more than 40 billion chickens are produced every year globally. For reasons of public concern and due to the large number of animals involved, it is considered by many people to be important to take care of the welfare and health status of the chickens reared under intensive farm conditions. Precision Livestock Farming (PLF) can support the farmer in his day to day routine management through the use of sensors, cameras and microphones, and these have the potential to improve production and to enable monitoring of welfare status. In this context, the 7FP EU-PLF project aims to test the efficiency of the use of those sensors at farm level. In particular, the aim of this study was to record and analyse broiler vocalisations under normal farm conditions and to identify the relation between animal sounds, and growth trends. Recordings were made at regular intervals, for the entire short production life of the birds, in order to evaluate the variation of frequency and bandwidth of the sounds emitted by the animals during the cycle of production. The recordings were made in an automated, non-invasive and non-intrusive way and the sound data was compared with the weight of the birds automatically measured by a 'step on scale' placed on the floor of the broiler house. Sound analysis was performed based on the amplitude and frequency of the sound signal in audio files recorded at farm level. Through analysis of the sounds recorded, a significant correlation (P<0.001) between the frequencies of the vocalisations recorded and the weight of the broilers was found across all production cycles and farms assessed. The ongoing goal will be the development of a tool able to automatically detect the growth of the animals based on the frequency of the vocalisation emitted by the birds at different ages, and as a possible tool for determining deviations from their expected growth trend
The Underlying Event and the Total Cross Section from Tevatron to the LHC
Multiple partonic interactions are widely used to simulate the hadronic final
state in high energy hadronic collisions, and successfully describe many
features of the data. It is important to make maximum use of the available
physical constraints on such models, particularly given the large extrapolation
from current high energy data to LHC energies. In eikonal models, the rate of
multiparton interactions is coupled to the energy dependence of the total cross
section. Using a Monte Carlo implementation of such a model, we study the
connection between the total cross section, the jet cross section, and the
underlying event. By imposing internal consistency on the model, we derive
constraints on its parameters at the LHC. By imposing internal consistency on
the model and comparing to current data we constrain the allowed range of its
parameters. We show that measurements of the total proton-proton cross-section
at the LHC are likely to break this internal consistency, and thus to require
an extension of the model. Likely such extensions are that hard scatters probe
a denser matter distribution inside the proton in impact parameter space than
soft scatters, a conclusion also supported by Tevatron data on double-parton
scattering, and/or that the basic parameters of the model are energy dependent.Comment: 17 pages, 6 figures, version accepted by JHE
Risk factor for footpad dermatitis and hock burns in broiler chickens
Footpad dermatitis (FPD) and hock burn (HB) are a major welfare concern in broiler chicken farming. In general, foot lesions are linked to poor environmental conditions. Ulcers caused by advanced lesions can negatively affect the gait of the birds, with effects on the welfare of animals, including, in the worst cases, inability to reach the feed or water. FPD and HB score data were collected manually at two broiler farms across Europe, during welfare assessments performed within the EU-PLF (Precision Livestock Farming) project, which is supported by the European Commission. This ongoing project aims to create "added value" for the farmer through the application of sensors and information technology at farm level. On those broiler farms, a number of variables such as temperature, relative humidity, ventilation rate, bird weight, light schedule, and feed and water consumption rates are measured automatically. The welfare of the chickens was assessed three times per cycle (at week 3, 4 and 5), scoring FPD, HB, gait score, cleanliness of the birds and litter quality. Data analysis was performed by combining data from the welfare assessments with environmental data collected by the automatic monitoring systems. The analysis showed that FPD and HB were more frequent when the flock was exposed to poor environmental conditions for prolonged periods of time. As environmental conditions can be measured continuously, and the risk factor for FPD and HB increases with poor environmental conditions, there is potential to develop a detection and control system for foot and hock lesions.</p
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