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The particle size of the forage has been proposed as a key factor to ensure a healthy rumen function and maintain dairy cow performance, but little work has been conducted on ryegrass silage (GS). To determine the effect of chop length of GS and GS:maize silage (MS) ratio on the performance, reticular pH, metabolism and eating behaviour of dairy cows, 16 multiparous Holstein-Friesian cows were used in a 4×4 Latin square design with four periods each of 28-days duration. Ryegrass was harvested and ensiled at two mean chop lengths (short and long) and included at two ratios of GS:MS (100:0 or 40:60 dry matter (DM) basis). The forages were fed in mixed rations to produce four isonitrogenous and isoenergetic diets: long chop GS, short chop GS, long chop GS and MS and short chop GS and MS. The DM intake (DMI) was 3.2 kg/day higher (P<0.001) when cows were fed the MS than the GS-based diets. The short chop length GS also resulted in a 0.9 kg/day DM higher (P<0.05) DMI compared with the long chop length. When fed the GS:MS-based diets, cows produced 2.4 kg/day more (P<0.001) milk than when fed diets containing GS only. There was an interaction (P<0.05) between chop length and forage ratio for milk yield, with a short chop length GS increasing yield in cows fed GS but not MS-based diets. An interaction for DM and organic matter digestibility was also observed (P<0.05), where a short chop length GS increased digestibility in cows when fed the GS-based diets but had little effect when fed the MS-based diet. When fed the MS-based diets, cows spent longer at reticular pH levels below pH 6.2 and pH 6.5 (P<0.01), but chop length had little effect. Cows when fed the MS-based diets had a higher (P<0.05) milk fat concentration of C18 : 2n-6 and total polyunsaturated fatty acids compared with when fed the GS only diets. In conclusion, GS chop length had little effect on reticular pH, but a longer chop length reduced DMI and milk yield but had little effect on milk fat yield. Including MS reduced reticular pH, but increased DMI and milk performance irrespective of the GS chop length.
The Kabwe Zn-Pb deposit (central Zambia) consists of a cluster of mixed sulfide and non-sulfide orebodies. The sulfide ores comprise sphalerite, galena, pyrite, chalcopyrite and accessory Ge-sulfides (±Ga and In). The non-sulfide ores comprise: (1) willemite-dominated zones encasing massive sulfide orebodies and (2) oxide-dominated alteration bands, overlying both the sulfide and Zn-silicate orebodies. This study focuses on the Ge, In and Ga distribution in the non-sulfide mineralization, and was carried out on a suite of Kabwe specimens, housed in the Natural History Museum Ore Collection (London). Petrography confirmed that the original sulfides were overprinted by at least two contrasting oxidation stages dominated by the formation of willemite (W1 and W2), and a further event characterized by weathering-related processes. Oxygen isotopic analyses have shown that W1 and W2 are unrelated genetically and furthermore not related to supergene Zn-Pb-carbonates in the oxide-dominated assemblage. The δ18O composition of 13.9–15.7‰ V-SMOW strongly supports a hydrothermal origin for W1. The δ18O composition of W2 (−3.5‰ to 0‰ V-SMOW) indicates that it precipitated from groundwaters of meteoric origin in either a supergene or a low-T hydrothermal environment. Gallium and Ge show a diversity of distribution among the range of Zn-bearing minerals. Gallium has been detected at the ppm level in W1, sphalerite, goethite and hematite. Germanium occurs at ppm levels in W1 and W2, and in scarcely detectable amounts in hemimorphite, goethite and hematite. Indium has low concentrations in goethite and hematite. These different deportments among the various phases are probably due to the different initial Ga, In and Ge abundances in the mineralization, to the different solubilities of the three elements at different temperatures and pH values, and finally to their variable affinities with the various minerals formed.
Secondary copper deficiency in ruminant animals is induced by high dietary levels of molybdenum (Mo), iron (Fe) or sulphur (S). Within the rumen, sulphur reacts with Mo to form a series of thiomolybdate molecules (TM) which may chelate copper. This reduces copper absorption or if TM is absorbed, inhibits copper metallo-enzyme activities. Parental administration of TM has resulted in an increase in Cu to the brain and an increase in Mo to the pituitaries (Haywood et al., 1998). This redistribution may alter neurological, endocrine and reproductive function. However, there are no reports on effects of endogenously produced TM on brain or pituitary trace element accumulation. The objective of this study was to determine the effect of dietary Mo or Fe on copper status and mineral retention in the pituitary gland and ovary of growing lambs.
Limitations of access have long restricted exploration and investigation of the cavities beneath ice shelves to a small number of drillholes. Studies of sea-ice underwater morphology are limited largely to scientific utilization of submarines. Remotely operated vehicles, tethered to a mother ship by umbilical cable, have been deployed to investigate tidewater-glacier and ice-shelf margins, but their range is often restricted. The development of free-flying autonomous underwater vehicles (AUVs) with ranges of tens to hundreds of kilometres enables extensive missions to take place beneath sea ice and floating ice shelves. Autosub2 is a 3600 kg, 6.7 m long AUV, with a 1600 m operating depth and range of 400 km, based on the earlier Autosub1 which had a 500 m depth limit. A single direct-drive d.c. motor and five-bladed propeller produce speeds of 1–2 m s−1. Rear-mounted rudder and stern-plane control yaw, pitch and depth. The vehicle has three sections. The front and rear sections are free-flooding, built around aluminium extrusion space-frames covered with glass-fibre reinforced plastic panels. The central section has a set of carbon-fibre reinforced plastic pressure vessels. Four tubes contain batteries powering the vehicle. The other three house vehicle-control systems and sensors. The rear section houses subsystems for navigation, control actuation and propulsion and scientific sensors (e.g. digital camera, upward-looking 300 kHz acoustic Doppler current profiler, 200 kHz multibeam receiver). The front section contains forward-looking collision sensor, emergency abort, the homing systems, Argos satellite data and location transmitters and flashing lights for relocation as well as science sensors (e.g. twin conductivity–temperature–depth instruments, multibeam transmitter, sub-bottom profiler, AquaLab water sampler). Payload restrictions mean that a subset of scientific instruments is actually in place on any given dive. The scientific instruments carried on Autosub are described and examples of observational data collected from each sensor in Arctic or Antarctic waters are given (e.g. of roughness at the underside of floating ice shelves and sea ice).
The quasar 3C147 was observed in October 1982 with a ten-station VLBI interferometer in an effort to search for possible superluminal motion (Simon et al. 1983) in the core. Previous observations, in 1976, had revealed that the core consisted of two compact components embedded in a larger halo. The new high quality map reveals that this double structure has disappeared and it is not possible to interpret the structural changes unambiguously in terms of an expansion or contraction.
3C 120 is a nearby radio galaxy (z = 0.033) that shows superluminal motions in its radio jet within one parsec of the nucleus. The apparent velocities of the moving features are approximately 1.5 mas/yr. This object is of particular interest because it is clearly identified with an N-type galaxy, unlike all other superluminal radio sources which are only seen in quasars and BL Lac objects. Because of the close proximity of 3C 120, we have been able to make a series of VLBI and VLA images at stepped resolutions, and thereby map the radio jet continuously from the radio nucleus (0.5 h−1 parsec) into the diffuse 400 h−1 kpc structure.
To describe the effect of universal methicillin-resistant Staphylococcus aureus (MRSA) decolonization therapy in a large intensive care unit (ICU) on the rates of MRSA cases and acquisitions in a UK hospital.
University Hospitals Birmingham (UHB) NHS Foundation Trust is a tertiary referral teaching hospital in Birmingham, United Kingdom, that provides clinical services to nearly 1 million patients every year.
A break-point time series analysis and kernel regression models were used to detect significant changes in the cumulative monthly numbers of MRSA bacteremia cases and acquisitions from April 2013 to August 2016 across the UHB system.
Prior to 2014, all ICU patients at UHB received universal MRSA decolonization therapy. In August 2014, UHB discontinued the use of universal decolonization due to published reports in the United Kingdom detailing the limited usefulness and cost-effectiveness of such an intervention. Break-point time series analysis of MRSA acquisition and bacteremia data indicated that break points were associated with the discontinuation and subsequent reintroduction of universal decolonization. Kernel regression models indicated a significant increase (P<.001) in MRSA acquisitions and bacteremia cases across UHB during the period without universal decolonization.
We suggest that routine decolonization for MRSA in a large ICU setting is an effective strategy to reduce the spread and incidence of MRSA across the whole hospital.
A range of options was explored to test the hypothesis that diets for dairy cows could be formulated to reduce the carbon footprint (CFP) of feed, increase efficiency of conversion of potentially human-edible feed into milk, increase nitrogen use efficiency (NUE) and reduce methane (CH4) emissions per kg milk. Diets based on grazed grass, grass silage, maize silage or straw, supplemented with raw material feeds, were formulated to meet requirements for metabolizable energy and metabolizable protein for a range of daily milk yields. At similar levels of milk yield, NUE, predicted CH4 emissions and diet CFP were generally higher for diets based on maize silage than for those based on grazed grass, grass silage or straw. Predicted CH4 emissions and human-edible proportion decreased, while NUE increased with the increasing level of milk yield. It is concluded that there is potential to reduce the environmental impact of milk production by altering diet formulation, but the extent to which this might occur is likely to depend on availability of raw material feeds with low CFPs.
We present an investigation of the halo dynamics of M31 using planetary nebulae velocities. We have performed on-band [OIII] and off-band continuum imaging for a 3.6 square degree area centred on M31 and follow-up spectroscopy for over 600 planetary nebulae candidates. In the future the halo mass will be measured and the mass distribution and velocity anisotropy will be constrained as a function of radius.
The Jodrell-IAC CMB experiments at Teide Observatory, Tenerife consisting of switching radiometers operating at 10, 15 and 33 GHz, and a 33 GHz short baseline interferometer, have covered up to an area of 1 steradian at angular scales from 1° to 10° (l = 20 − 210). Sensitivities of 10μK per beam area have been reached for a combination the most sensitive experiments allowing a measure of the CMB fluctuation amplitude of 30±8μK using mapping techniques which fully exploit the whole data set. Attempts have been made to separate out galactic radio foregrounds and to place limits on a possible spinning dust contribution.
Jodrell Bank Observatory is responsible for the Front end modules (FEMs) for 30 GHz for LFI, with IAC being responsible for the hybrids and any phase switch. The University of Cantabria are responsible for the Back end modules (BEMs). Developments have been made to test prototypes both warm and cold for the FEMs. This is evolving towards flight hardware through an elegant breadboard phase EBB. Results of system performance show both white noise and 1/f characteristics.
Cosmic Microwave Observations at 1° scales are extremely important on the understanding of modern Cosmology. At those angular scales the CMB power spectrum presents the first Doppler Peak. The position and amplitude of this peak provide strong constraints on cosmological parameters as H0 and Ω0. The JBO-IAC interferometer has observed those angular scales as well as the BOOMERANG and MAXIMA teams. The results from these groups show the existence of the first Doppler Peak. We present a detailed estimate of the galactic contribution to the JBO-IAC interferometer data set using data from the Tenerife and COSMOSOMAS experiments.
A series of VLBI surveys of complete samples of radio sources selected at 5 GHz (Pearson & Readhead 1988, hereafter PR; Xu et al. 1995 and references therein) has revealed that ≃ 10% of the objects are “Compact Symmetric Objects” (CSOs), in which high-luminosity radio emission regions are seen on both sides of the center of activity on scales less than one kiloparsec (Phillips & Mutel 1982; Readhead et al. 1984; Conway et al. 1992; Wilkinson et al. 1994). In order to be sure that an object is a CSO, either the center of activity must be pinpointed (Taylor et al. 1996) or compelling morphological evidence of symmetric structure must be found.
We present first results from the analysis of multi-epoch VLBI observations of 241 sources in the CJ-F sample (Caltech Jodrell-Flat-spectrum, Taylor et al. 1996). We have been obtaining 5 GHz VLBI (global and VLBA) snapshot observations of the CJ-F sources (complete with 293 sources) since 1990 in order to create a valid database for thorough statistical tests of pc-scale jet motion in AGN. All 241 CJ-F AGN have been observed at least three times with the VLBA, which enables us to investigate jet component motions and paths. In particular, we concentrate on the analysis of those properties supposed to be essential for gamma-ray production, i.e., superluminal motion and bending.
The ability to make reliable maps of radio sources at any available frequency and on all feasible angular scales is obviously a fundamental goal of observational radio astronomy. Unfortunately, until very recently, our map-making capability has been extremely restricted, limited in fact to those physical baselines and frequencies where phase-stable interferometers could be operated. However it is now becoming increasingly clear that phase stability is not an essential prerequisite for reliable mapping. The basic point is that whereas in principle there are an infinite number of brightness distributions which could give rise to the observed amplitudes of a set of Fourier components whose phases are unknown, in practice the a priori information that the required distribution is real and positive severely constrains the range of possibilities. Both Bates and his co-workers (e.g. Bates and Napier 1974) and Ross et al. (1978) have pointed out that the brightness distributions we are seeking are examples of ‘entire’ functions. In particular it is known that the real and imaginary parts of such functions are not independent (see references in Ross et al.) and that by studying the positions of their complex zeroes one may well be able to deduce the brightness distribution from knowing only the modulus of its Fourier transform. Unfortunately such a rigorous approach appears to be rather difficult to implement in practice. However the results of Napier and Bates (1974) have confirmed that in two dimensions reliable structure determinations can be made without phase information.