2,156 research outputs found
The UVES Spectral Quasar Absorption Database (SQUAD) Data Release 1: The first 10 million seconds
We present the first data release (DR1) of the UVES Spectral Quasar
Absorption Database (SQUAD), comprising 467 fully reduced, continuum-fitted
high-resolution quasar spectra from the Ultraviolet and Visual Echelle
Spectrograph (UVES) on the European Southern Observatory's Very Large
Telescope. The quasars have redshifts -5, and a total exposure time of 10
million seconds provides continuum-to-noise ratios of 4-342 (median 20) per
2.5-km/s pixel at 5500 \AA. The SQUAD spectra are fully reproducible from the
raw, archival UVES exposures with open-source software, including our
UVES_popler tool for combining multiple extracted echelle exposures which we
document here. All processing steps are completely transparent and can be
improved upon or modified for specific applications. A primary goal of SQUAD is
to enable statistical studies of large quasar and absorber samples, and we
provide tools and basic information to assist three broad scientific uses:
studies of damped Lyman- systems (DLAs), absorption-line surveys and
time-variable absorption lines. For example, we provide a catalogue of 155 DLAs
whose Lyman- lines are covered by the DR1 spectra, 18 of which are
reported for the first time. The HI column densities of these new DLAs are
measured from the DR1 spectra. DR1 is publicly available and includes all
reduced data and information to reproduce the final spectra.Comment: 21 pages, 18 figures. Accepted by MNRAS. All final quasar spectra,
reduced contributing exposures, and supplementary material available via
https://github.com/MTMurphy77/UVES_SQUAD_DR
The effects of altering milking frequency and/or diet in early lactation on the energy balance, production and reproduction of dairy cows.
End of Project ReportIt has been suggested that negative energy balance (NEB) in the immediate
post-partum period is potentially an important factor in the association
between increasing milk output and declining reproductive performance. The
objective of this project was to design an experimental model that could be
used to impose different degrees of NEB immediately after calving and to
examine the effect of this model on dry matter intake (DMI), milk production,
energy balance (EB), metabolic and reproductive hormonal profiles, the onset
and pattern of post-partum ovarian cyclicity and reproductive physiology
around AI.
Two experiments were carried out to evaluate the effects of milking frequency
and diet on DMI, production, energy balance and blood metabolites and
hormones in the first 4 weeks after calving and subsequent reproduction.
Reducing milking frequency from either thrice or twice daily to once daily
reduced DMI but also reduced milk production. This resulted in a better EB in
once daily milked cows in both experiments, the reduction being significant in
the first. Milk production during the 4-week treatment period was reduced by
23 and 20 percent by reducing milking frequency from thrice to once daily in
experiments 1 and 2, respectively. There was a reduction of approximately 10
percent in the cumulative yield up to week 20 of lactation in experiment 1 and
of approximately 9 percent in total lactation yield in experiment 2. Reducing
milking frequency resulted in increased plasma glucose, insulin and IGF-1
concentrations and reduced non-esterified fatty acid (NEFA) and beta
hydroxybutyrate (BHB) concentrations. Conception rates to first service or
overall pregnancy rates were not different between milking frequency
treatments but once daily milking resulted in a shorter interval to first ovulation
than thrice daily milking, due to a higher proportion of cows on this treatment
ovulating the first post-partum dominant follicle. Increasing the energy density
2
of the diet increased DMI and milk production with no consequent effect on
energy balance.
Logistic regression on the combined data from the two experiments showed
that lower energy intake, greater NEB and lower milk protein content and
were significantly associated with poorer conception to first service. Lower
plasma IGF-1 concentrations in experiment 2 were also associated with a
lower conception rate to first service.
A third experiment which investigated protein concentration in the concentrate
combined with concentrate feeding level post calving (for two groups of cows
in different body condition score at calving) showed no effect of post calving
diet on BCS change.
Overall the results suggest that reducing milking frequency to once per day
during the first 4 weeks of lactation reduces NEB and appears to be a suitable
strategy for altering energy balance at this time. However, the short-term
reduction in milking frequency immediately post partum reduces total lactation
yields. Blood metabolite and hormonal concentrations indicate better energy
balance for cows milked once daily. Increasing dietary energy density or
reducing the protein content of the diet does not appear to be effective in
changing energy balance in early lactation. Decreased NEB in the first 4
weeks post-partum is associated with an improved conception rate to first
service
EWPD Constraints on Flavor Symmetric Vector Fields
Electroweak precision data constraints on flavor symmetric vector fields are
determined. The flavor multiplets of spin one that we examine are the complete
set of fields that couple to quark bi-linears at tree level while not initially
breaking the quark global flavor symmetry group. Flavor safe vector masses
proximate to, and in some cases below, the electroweak symmetry breaking scale
are found to be allowed. Many of these fields provide a flavor safe mechanism
to explain the t tbar forward backward anomaly, and can simultaneously
significantly raise the allowed values of the Standard Model Higgs mass
consistent with electroweak precision data.Comment: Matches version published in JHE
MitoNeoD:a mitochondria-targeted superoxide probe
Mitochondrial superoxide (O2⋅−) underlies much oxidative damage and redox signaling. Fluorescent probes can detect O2⋅−, but are of limited applicability in vivo, while in cells their usefulness is constrained by side reactions and DNA intercalation. To overcome these limitations, we developed a dual-purpose mitochondrial O2⋅− probe, MitoNeoD, which can assess O2⋅− changes in vivo by mass spectrometry and in vitro by fluorescence. MitoNeoD comprises a O2⋅−-sensitive reduced phenanthridinium moiety modified to prevent DNA intercalation, as well as a carbon-deuterium bond to enhance its selectivity for O2⋅− over non-specific oxidation, and a triphenylphosphonium lipophilic cation moiety leading to the rapid accumulation within mitochondria. We demonstrated that MitoNeoD was a versatile and robust probe to assess changes in mitochondrial O2⋅− from isolated mitochondria to animal models, thus offering a way to examine the many roles of mitochondrial O2⋅−production in health and disease
Measuring Inequalities in the Distribution of Health Workers: The case of Tanzania.
The overall human resource shortages and the distributional inequalities in the health workforce in many developing countries are well acknowledged. However, little has been done to measure the degree of inequality systematically. Moreover, few attempts have been made to analyse the implications of using alternative measures of health care needs in the measurement of health workforce distributional inequalities. Most studies have implicitly relied on population levels as the only criterion for measuring health care needs. This paper attempts to achieve two objectives. First, it describes and measures health worker distributional inequalities in Tanzania on a per capita basis; second, it suggests and applies additional health care needs indicators in the measurement of distributional inequalities. We plotted Lorenz and concentration curves to illustrate graphically the distribution of the total health workforce and the cadre-specific (skill mix) distributions. Alternative indicators of health care needs were illustrated by concentration curves. Inequalities were measured by calculating Gini and concentration indices.\ud
There are significant inequalities in the distribution of health workers per capita. Overall, the population quintile with the fewest health workers per capita accounts for only 8% of all health workers, while the quintile with the most health workers accounts for 46%. Inequality is perceptible across both urban and rural districts. Skill mix inequalities are also large. Districts with a small share of the health workforce (relative to their population levels have an even smaller share of highly trained medical personnel. A small share of highly trained personnel is compensated by a larger share of clinical officers (a middle-level cadre) but not by a larger share of untrained health workers. Clinical officers are relatively equally distributed. Distributional inequalities tend to be more pronounced when under-five deaths are used as an indicator of health care needs. Conversely, if health care needs are measured by HIV prevalence, the distributional inequalities appear to decline. The measure of inequality in the distribution of the health workforce may depend strongly on the underlying measure of health care needs. In cases of a non-uniform distribution of health care needs across geographical areas, other measures of health care needs than population levels may have to be developed in order to ensure a more meaningful measurement of distributional inequalities of the health workforce
Determination of a suitable low-dose abdominopelvic CT protocol using model-based iterative reconstruction through cadaveric study.
Introduction: Cadaveric studies provide a means of safely assessing new technologies and optimizing scanning prior to clinical validation. Reducing radiation exposure in a clinical setting can entail incremental dose reductions to avoid missing important clinical findings. The use of cadavers allows assessment of the impact of more substantial dose reductions on image quality. Our aim was to identify a suitable low‐dose abdominopelvic CT protocol for subsequent clinical validation. Methods: Five human cadavers were scanned at one conventional dose and three low‐dose settings. All scans were reconstructed using three different reconstruction algorithms: filtered back projection (FBP), hybrid iterative reconstruction (60% FBP and 40% adaptive statistical iterative reconstruction (ASIR40)), and model‐based iterative reconstruction (MBIR). Two readers rated the image quality both quantitatively and qualitatively. Results: Model‐based iterative reconstruction images had significantly better objective image noise and higher qualitative scores compared with both FBP and ASIR40 images at all dose levels. The greatest absolute noise reduction, between MBIR and FBP, of 34.3 HU (equating to a 68% reduction) was at the lowest dose level. MBIR reduced image noise and improved image quality even in CT images acquired with a mean radiation dose reduction of 62% compared with conventional dose studies reconstructed with ASIR40, with lower levels of objective image noise, superior diagnostic acceptability and contrast resolution, and comparable subjective image noise and streak artefact scores. Conclusion: This cadaveric study demonstrates that MBIR reduces image noise and improves image quality in abdominopelvic CT images acquired with dose reductions of up to 62%
Hydroxymethylglutaryl-CoA reductase inhibition with simvastatin in acute lung injury to reduce pulmonary dysfunction (HARP-2) trial : study protocol for a randomized controlled trial
Acute lung injury (ALI) is a common devastating clinical syndrome characterized by life-threatening respiratory failure requiring mechanical ventilation and multiple organ failure. There are in vitro, animal studies and pre-clinical data suggesting that statins may be beneficial in ALI. The Hydroxymethylglutaryl-CoA reductase inhibition with simvastatin in Acute lung injury to Reduce Pulmonary dysfunction (HARP-2) trial is a multicenter, prospective, randomized, allocation concealed, double-blind, placebo-controlled clinical trial which aims to test the hypothesis that treatment with simvastatin will improve clinical outcomes in patients with ALI
Complexity of multi-dimensional spontaneous EEG decreases during propofol induced general anaesthesia
Emerging neural theories of consciousness suggest a correlation between a specific type of neural dynamical complexity and the level of consciousness: When awake and aware, causal interactions between brain regions are both integrated (all regions are to a certain extent connected) and differentiated (there is inhomogeneity and variety in the interactions). In support of this, recent work by Casali et al (2013) has shown that Lempel-Ziv complexity correlates strongly with conscious level, when computed on the EEG response to transcranial magnetic stimulation. Here we investigated complexity of spontaneous high-density EEG data during propofol-induced general anaesthesia. We consider three distinct measures: (i) Lempel-Ziv complexity, which is derived from how compressible the data are; (ii) amplitude coalition entropy, which measures the variability in the constitution of the set of active channels; and (iii) the novel synchrony coalition entropy (SCE), which measures the variability in the constitution of the set of synchronous channels. After some simulations on Kuramoto oscillator models which demonstrate that these measures capture distinct ‘flavours’ of complexity, we show that there is a robustly measurable decrease in the complexity of spontaneous EEG during general anaesthesia
- …