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Sub-acute ruminal acidosis (SARA) can reduce the production efficiency and impair the welfare of cattle, potentially in all production systems. The aim of this study was to characterise measurable postmortem observations from divergently managed intensive beef finishing farms with high rates of concentrate feeding. At the time of slaughter, we obtained samples from 19 to 20 animals on each of 6 beef finishing units (119 animals in total) with diverse feeding practices, which had been subjectively classified as being high risk (three farms) or low risk (three farms) for SARA on the basis of the proportions of barley, silage and straw in the ration. We measured the concentrations of histamine, lipopolysaccharide (LPS), lactate and other short-chain fatty acids (SCFAs) in ruminal fluid, LPS and SCFA in caecal fluid. We also took samples of the ventral blind sac of the rumen for histopathology, immunohistopathology and gene expression. Subjective assessments were made of the presence of lesions on the ruminal wall, the colour of the lining of the ruminal wall and the shape of the ruminal papillae. Almost all variables differed significantly and substantially among farms. Very few pathological changes were detected in any of the rumens examined. The animals on the high-risk diets had lower concentrations of SCFA and higher concentrations of lactate and LPS in the ruminal fluid. Higher LPS concentrations were found in the caecum than the rumen but were not related to the risk status of the farm. The diameters of the stratum granulosum, stratum corneum and of the vasculature of the papillae, and the expression of the gene TLR4 in the ruminal epithelium were all increased on the high-risk farms. The expression of IFN-γ and IL-1β and the counts of cluster of differentiation 3 positive and major histocompatibility complex class two positive cells were lower on the high-risk farms. High among-farm variation and the unbalanced design inherent in this type of study in the field prevented confident assignment of variation in the dependent variables to individual dietary components; however, the CP percentage of the total mixed ration DM was the factor that was most consistently associated with the variables of interest. Despite the strong effect of farm on the measured variables, there was wide inter-animal variation.
Astrophysics Telescope for Large Area Spectroscopy Probe is a concept for a National Aeronautics and Space Administration probe-class space mission that will achieve ground-breaking science in the fields of galaxy evolution, cosmology, Milky Way, and the Solar System. It is the follow-up space mission to Wide Field Infrared Survey Telescope (WFIRST), boosting its scientific return by obtaining deep 1–4 μm slit spectroscopy for ∼70% of all galaxies imaged by the ∼2 000 deg2 WFIRST High Latitude Survey at z > 0.5. Astrophysics Telescope for Large Area Spectroscopy will measure accurate and precise redshifts for ∼200 M galaxies out to z < 7, and deliver spectra that enable a wide range of diagnostic studies of the physical properties of galaxies over most of cosmic history. Astrophysics Telescope for Large Area Spectroscopy Probe and WFIRST together will produce a 3D map of the Universe over 2 000 deg2, the definitive data sets for studying galaxy evolution, probing dark matter, dark energy and modifications of General Relativity, and quantifying the 3D structure and stellar content of the Milky Way. Astrophysics Telescope for Large Area Spectroscopy Probe science spans four broad categories: (1) Revolutionising galaxy evolution studies by tracing the relation between galaxies and dark matter from galaxy groups to cosmic voids and filaments, from the epoch of reionisation through the peak era of galaxy assembly; (2) Opening a new window into the dark Universe by weighing the dark matter filaments using 3D weak lensing with spectroscopic redshifts, and obtaining definitive measurements of dark energy and modification of General Relativity using galaxy clustering; (3) Probing the Milky Way’s dust-enshrouded regions, reaching the far side of our Galaxy; and (4) Exploring the formation history of the outer Solar System by characterising Kuiper Belt Objects. Astrophysics Telescope for Large Area Spectroscopy Probe is a 1.5 m telescope with a field of view of 0.4 deg2, and uses digital micro-mirror devices as slit selectors. It has a spectroscopic resolution of R = 1 000, and a wavelength range of 1–4 μm. The lack of slit spectroscopy from space over a wide field of view is the obvious gap in current and planned future space missions; Astrophysics Telescope for Large Area Spectroscopy fills this big gap with an unprecedented spectroscopic capability based on digital micro-mirror devices (with an estimated spectroscopic multiplex factor greater than 5 000). Astrophysics Telescope for Large Area Spectroscopy is designed to fit within the National Aeronautics and Space Administration probe-class space mission cost envelope; it has a single instrument, a telescope aperture that allows for a lighter launch vehicle, and mature technology (we have identified a path for digital micro-mirror devices to reach Technology Readiness Level 6 within 2 yr). Astrophysics Telescope for Large Area Spectroscopy Probe will lead to transformative science over the entire range of astrophysics: from galaxy evolution to the dark Universe, from Solar System objects to the dusty regions of the Milky Way.
We present the results from the state-of-the-art wide-field survey of the M81 galaxy group that we are conducting with Hyper Suprime-Cam on Subaru Telescope. Our photometry reaches about 2 mag below the tip of the red giant branch (RGB) and reveals the spatial distribution of both old and young stars over an area of 5°2 around the M81. The young main-sequence (MS) stars closely follow the HI distribution and can be found in a stellar stream between M81 and NGC 3077 and in numerous outlying stellar associations. Our survey also reveals for the first time the very extended (>2 × R25) halos of RGB stars around M81, M82, and NGC 3077, as well as faint tidal streams that link these systems. The gravitational interactions between M81, M82 and NGC 3077 galaxies induced star formation in tidally stripped gas, and also significantly perturbed the older stellar components leading to disturbed halo morphologies.
The public health threat posed by zoonotic Plasmodium knowlesi appears to be growing: it is increasingly reported across South East Asia, and is the leading cause of malaria in Malaysian Borneo. Plasmodium knowlesi threatens progress towards malaria elimination as aspects of its transmission, such as spillover from wildlife reservoirs and reliance on outdoor-biting vectors, may limit the effectiveness of conventional methods of malaria control. The development of new quantitative approaches that address the ecological complexity of P. knowlesi, particularly through a focus on its primary reservoir hosts, will be required to control it. Here, we review what is known about P. knowlesi transmission, identify key knowledge gaps in the context of current approaches to transmission modelling, and discuss the integration of these approaches with clinical parasitology and geostatistical analysis. We highlight the need to incorporate the influences of fine-scale spatial variation, rapid changes to the landscape, and reservoir population and transmission dynamics. The proposed integrated approach would address the unique challenges posed by malaria as a zoonosis, aid the identification of transmission hotspots, provide insight into the mechanistic links between incidence and land use change and support the design of appropriate interventions.
GaN and its alloys are promising candidates for high temperature thermoelectric (TE) materials due to their high Seebeck coefficient and high thermal and mechanical stability. Moreover, these materials can overcome the toxicity concern of current Te-based TE materials, such as Bi2Te3 and PbTe. These materials have recently shown a higher Seebeck coefficient than that of SiGe in high temperature region because their large bandgap characteristic eliminates the bipolar conduction. In this study, we report the room temperature thermoelectric properties of p-type Mg doped GaN, grown by metalorganic chemical vapor deposition (MOCVD) on sapphire substrate with various carrier concentrations. Undoped and n-type GaN are also incorporated with p-type GaN films to make comparison. The structural, optical, electrical, and thermal properties of the samples were examined by X-ray diffraction, photoluminescence, van der Pauw hall-effect, and thermal gradient methods, respectively. The Seebeck coefficient ranging from 710-900µV/K at room temperature of Mg: GaN were observed, which further indicated their potential TE applications.
Efficient emergency and disaster response is challenged by environmental conditions exceeding test reagent storage and operating specifications. We assessed the effectiveness of vial and foil packaging in preserving point-of-care (POC) glucose and lactate test strip performance in humid conditions.
Glucose and lactate test strips in both packaging were exposed to mean relative humidity of 97.0 ± 1.1% in an environmental chamber for up to 168 hours. At defined time points, stressed strips were removed and tested in pairs with unstressed strips using whole blood samples spiked to glucose concentrations of 60, 100, and 250 mg/dL (n = 20 paired measurements per level). A Wilcoxon signed rank test was used to compare stressed and unstressed test strip measurements.
Stressed glucose and lactate test strip measurements differed significantly from unstressed strips, and were inconsistent between experimental trials. Median glucose paired difference was as high as 12.5 mg/dL at the high glucose test concentration. Median lactate bias was −0.2 mmol/L. Stressed strips from vial (3) and foil (7) packaging failed to produce results.
Both packaging designs appeared to protect glucose and lactate test strips for at least 1 week of high humidity stress. Documented strip failures revealed the need for improved manufacturing process. (Disaster Med Public Health Preparedness. 2014;0:1–7)
The application of metabolomics in multi-centre studies is increasing. The aim of the present study was to assess the effects of geographical location on the metabolic profiles of individuals with the metabolic syndrome. Blood and urine samples were collected from 219 adults from seven European centres participating in the LIPGENE project (Diet, genomics and the metabolic syndrome: an integrated nutrition, agro-food, social and economic analysis). Nutrient intakes, BMI, waist:hip ratio, blood pressure, and plasma glucose, insulin and blood lipid levels were assessed. Plasma fatty acid levels and urine were assessed using a metabolomic technique. The separation of three European geographical groups (NW, northwest; NE, northeast; SW, southwest) was identified using partial least-squares discriminant analysis models for urine (R2X: 0·33, Q2: 0·39) and plasma fatty acid (R2X: 0·32, Q2: 0·60) data. The NW group was characterised by higher levels of urinary hippurate and N-methylnicotinate. The NE group was characterised by higher levels of urinary creatine and citrate and plasma EPA (20 : 5 n-3). The SW group was characterised by higher levels of urinary trimethylamine oxide and lower levels of plasma EPA. The indicators of metabolic health appeared to be consistent across the groups. The SW group had higher intakes of total fat and MUFA compared with both the NW and NE groups (P≤ 0·001). The NE group had higher intakes of fibre and n-3 and n-6 fatty acids compared with both the NW and SW groups (all P< 0·001). It is likely that differences in dietary intakes contributed to the separation of the three groups. Evaluation of geographical factors including diet should be considered in the interpretation of metabolomic data from multi-centre studies.
We describe the successful creation of new reef habitat on Pulau Weh, Indonesia. Coral cover on artificial reef modules increased from a mean of 24±SE 2.4% 1 year after the initial attachment of Acropora spp. coral fragments to 64±SE 4.8% after 3 years. The artificial reef modules were also rapidly colonized by coral recruits. Recruit densities were 53±SE 3.2 m−2 on modules that had been submerged for only 1 year, nearly twice as high as recruit densities on natural reef substratum (31±2.8 m−2). Consequently, the original Acropora assemblage had increased to include at least 23 coral taxa, including 10 additional Acropora species. The artificial reefs also supported at least 29 reef fish species, from 11 families. Unfortunately, this initial success in habitat creation was abruptly halted by a rapid rise in sea temperature in May 2010 that killed almost all corals on the artificial reefs and on nearby natural reefs. Notwithstanding the general view that reef rehabilitation is yet to deliver ecological and conservation benefits at meaningful scales, other benefits of this project included raising the awareness of reef conservation in the local community, promotion of tourism on Pulau Weh and job creation. We conclude, therefore, that habitat creation has a legitimate role as part of an integrated marine conservation strategy.
We have used high-resolution, HST WFC3/IR, near-infrared imaging to conduct a detailed bulge-disk decomposition of the morphologies of ≃ 200 of the most massive (M* > 1011 M⊙) galaxies at 1 < z < 3 in the CANDELS-UDS field. We find that, while such massive galaxies at low redshift are generally bulge-dominated, at redshifts 1<z<2 they are predominantly mixed bulge+disk systems, and by z > 2 they are mostly disk-dominated. Interestingly, we find that while most of the quiescent galaxies are bulge-dominated, a significant fraction (25–40%) of the most quiescent galaxies, have disk-dominated morphologies. Thus, our results suggest that the physical mechanisms which quench star-formation activity are not simply connected to those responsible for the morphological transformation of massive galaxies.
The mechanism leading to RT ferromagnetism in Gd-doped GaN is not agreed upon, despite many experimental and theoretical reports. Oxygen impurities have been proposed as a possible contributor to ferromagnetic behavior in GaN:Gd films. In this report, GaN:Gd thin films grown by MOCVD using two different metalorganic Gd precursors are examined. The two precursors are (TMHD)3Gd, which contains oxygen, and Cp3Gd, which does not. The films have been characterized by XRD, VSM, and EDS. EDS measurements indicate that the TMHD3Gd samples contain oxygen, while the Cp3Gd samples do not, and VSM scans show that the TMHD3Gd samples exhibit much higher magnetic moments than the Cp3Gd samples, supporting the theory that oxygen enhances the ferromagnetic behavior of GaN:Gd.
The emission from a light emitting diode (LED) that is emitted under the metal electrode cannot escape into free space. A current blocking layer (CBL) is used to address this issue by forcing the current to flow laterally under the electrode reducing the emission absorbed and hence increasing the overall efficiency of the LED. In this paper a new method to fabricate Schottky and isolating CBLs in GaN LED are investigated. Optical and electrical measurements of these vertical LEDs with and without CBL show different light output powers at identical current densities. The results of this study indicate that CBLs could also be used to suppress the efficiency droop effect for GaN LEDs.
In this paper the thermoelectric properties–the Seebeck coefficient, the electrical conductivity and the power factor – of GaN and InGaN thin films grown by Metal Organic Vapor Deposition (MOCVD) are reported. The Seebeck coefficient and power factor of InGaN decreases with increasing indium content, although the electrical conductivity shows an inverse behavior. P-type doped samples demonstrated the highest Seebeck coefficient (637 μV/K in GaN:Mg, 1200 μV/K in InGaN:Mg) but the lowest power factor (0.1x10-4 W/m-K for GaN:Mg, 0.4x10-4 W/m-K for InGaN:Mg). The Seebeck coefficient of the doped GaN thin films decreased linearly with log of the carrier concentration. GaN:Si exhibited a maximum power factor of 9.1x10-4 W/m-K with a carrier concentration of 1.6x1018 cm-3, and In0.1Ga0.9N exhibited a maximum power factor of 109x10-4 W/m-K with a carrier concentration of 1.2x1018 cm-3. The results also indicate that GaN and InGaN-based materials could potentially be useful materials for TE applications at high temperatures.
Thin film gallium nitride (GaN) scintillators have been produced by MOCVD and made neutron-sensitive by applying an enriched lithium-6 fluoride (6LiF) conversion layer. The 6Li(n,α) reaction produces both alpha and triton particles, which have very penetration depths in GaN. The range and energy deposition characteristics of these particles in GaN have been simulated. Alpha-induced scintillation was measured in silicon-doped GaN using an americium-241 (241Am) source. The thermal neutron responses of the 6LiF-coated GaN scintillator were tested using two thermal neutron sources, an 241Am-Be source inside a graphite pile and a reactor source. The scintillator was found to have a linear response to thermal neutron flux level over a range of more than three orders of magnitude.
The objective of this research was to assess current patterns of hospital antibiotic prescribing in Northern Ireland and to determine targets for improving the quality of antibiotic prescribing. A point prevalence survey was conducted in four acute teaching hospitals. The most commonly used antibiotics were combinations of penicillins including β-lactamase inhibitors (33·6%), metronidazole (9·1%), and macrolides (8·1%). The indication for treatment was recorded in 84·3% of the prescribing episodes. A small fraction (3·9%) of the surgical prophylactic antibiotic prescriptions was for >24 h. The results showed that overall 52·4% of the prescribed antibiotics were in compliance with the hospital antibiotic guidelines. The findings identified the following indicators as targets for quality improvement: indication recorded in patient notes, the duration of surgical prophylaxis and compliance with hospital antibiotic guidelines. The results strongly suggest that antibiotic use could be improved by taking steps to address the identified targets for quality improvement.