135 research outputs found

    Effects of Molybdenum Supplementation on Performance of Forage‐fed SteersReceiving High‐sulfur Water

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    There has been on‐going research in the area of the consumption of high‐sulfur (S) water by steers grazing rangeland as well as forage‐fed steers in a feedlot setting. During the summer of 2009, a trial was conducted on the effects of high‐S water in finishing steers supplemented with molybdenum (Mo). The main purpose of the research was to gather data that may aid in the formulation of a supplement to counteract the negative effects of high‐S water consumed by ruminant livestock species in areas where sulfur concentration in water sources is a risk to animal health and performance. The specific focus of this trial was to determine whether the feeding of supplemental Mo would improve animal health and performance by decreasing the formation of hydrogen sulfide gas (H2S) in the rumen. Yearling steers (n=96) were used for a 56‐d trial. The trial consisted of 3 treatment groups; a low‐S water group and two high‐S water groups. One high‐S water treatment group received the same pellet that the low‐S group was given and the other high‐S water treatment group received a pellet with supplemental Mo included. Rumen gas cap H2S was collected on d ‐1, 29 and 57. Weights were recorded on d ‐2, ‐1, 29, 56 and 57. There were no differences between treatments in water intake (P= 0.719), but feed intake was reduced in the steers receiving the supplemental Mo (P \u3c 0.001). There was a significant difference in ruminal H2S due to treatment (P= 0.014), with higher ruminal H2S in the steers receiving the supplemental Mo. Steers receiving the Mo supplement had lower ADG than steers in the other treatments (P= 0.009). Throughout the duration of the trial, two steers were removed from the trial due to advanced symptoms of sulfur‐induced PEM (sPEM) from the high‐S treatment with no supplemental M

    Copper Supplementation of Grazing Yearling Steers Supplemented withMolybdenum While Consuming High‐sulfur Water

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    There has been on‐going research conducted by South Dakota State University in the area of the consumption of high‐sulfur (S) water by steers grazing rangeland. During the summer of 2009 a trial was conducted in cooperation with the University of Wyoming on the effects of copper supplementation of grazing pasture steers supplemented with molybdenum (Mo), while drinking high‐sulfur water. The main purpose of this experiment was to gather data that may aide in the formulation of a method to counteract the negative effects of high‐S water consumed by ruminant livestock species in areas where sulfur concentrations in water sources causes risk to animal health and performance. Yearling steers (n=120) were assigned randomly to 9 replicate groups, 3 replicates of 3 treatments for a 52 d experiment. All groups were provided with high‐S water containing on average 2,201 mg‱kg‐1 of sulfate. Additionally, all treatment groups received 100 mg‱kg‐1 of supplemental Mo as an antagonist that would bind excess S. Unfortunately, Mo also binds copper (Cu), indicating that supplemental Cu may be necessary. Therefore treatments differed in level of supplemental copper: treatments 1 through 3 received 0, 75, or 150 mg‱kg‐1 of supplemental Cu, respectively. Prior to the trial, mid‐trial and at the conclusion of the trial, ruminal H2S gas cap levels were collected. Animal weights were recorded d ‐2, ‐1, 28, 52 and 53. Over the entire course of the experiment there was a significant difference in ADG due to treatment (P\u3c 0.001). There were no differences in water consumption as a result of treatment (P= 0.618). No differences were observed in ruminal H2S due to treatment. No animal losses occurred due to the consumption of high‐S water in this trial

    Supernovae as seen by off-center observers in a local void

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    Inhomogeneous universe models have been proposed as an alternative explanation for the apparent acceleration of the cosmic expansion that does not require dark energy. In the simplest class of inhomogeneous models, we live within a large, spherically symmetric void. Several studies have shown that such a model can be made consistent with many observations, in particular the redshift--luminosity distance relation for type Ia supernovae, provided that the void is of Gpc size and that we live close to the center. Such a scenario challenges the Copernican principle that we do not occupy a special place in the universe. We use the first-year Sloan Digital Sky Survey-II supernova search data set as well as the Constitution supernova data set to put constraints on the observer position in void models, using the fact that off-center observers will observe an anisotropic universe. We first show that a spherically symmetric void can give good fits to the supernova data for an on-center observer, but that the two data sets prefer very different voids. We then continue to show that the observer can be displaced at least fifteen percent of the void scale radius from the center and still give an acceptable fit to the supernova data. When combined with the observed dipole anisotropy of the cosmic microwave background however, we find that the data compells the observer to be located within about one percent of the void scale radius. Based on these results, we conclude that considerable fine-tuning of our position within the void is needed to fit the supernova data, strongly disfavouring the model from a Copernican principle point of view.Comment: 20 pages, 6 figures, matches the published versio

    Single-field inflation constraints from CMB and SDSS data

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    We present constraints on canonical single-field inflation derived from WMAP five year, ACBAR, QUAD, BICEP data combined with the halo power spectrum from SDSS LRG7. Models with a non-scale-invariant spectrum and a red tilt n_s < 1 are now preferred over the Harrison-Zel'dovich model (n_s = 1, tensor-to-scalar ratio r = 0) at high significance. Assuming no running of the spectral indices, we derive constraints on the parameters (n_s, r) and compare our results with the predictions of simple inflationary models. The marginalised credible intervals read n_s = 0.962^{+0.028}_{-0.026} and r < 0.17 (at 95% confidence level). Interestingly, the 68% c.l. contours favour mainly models with a convex potential in the observable region, but the quadratic potential model remains inside the 95% c.l. contours. We demonstrate that these results are robust to changes in the datasets considered and in the theoretical assumptions made. We then consider a non-vanishing running of the spectral indices by employing different methods, non-parametric but approximate, or parametric but exact. With our combination of CMB and LSS data, running models are preferred over power-law models only by a Delta chi^2 ~ 5.8, allowing inflationary stages producing a sizable negative running -0.063^{+0.061}_{-0.049} and larger tensor-scalar ratio r < 0.33 at the 95% c.l. This requires large values of the third derivative of the inflaton potential within the observable range. We derive bounds on this derivative under the assumption that the inflaton potential can be approximated as a third order polynomial within the observable range.Comment: 32 pages, 7 figures. v2: additional references, some typos corrected, passed to JCAP style. v3: minor changes, matches published versio

    Testing the Void against Cosmological data: fitting CMB, BAO, SN and H0

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    In this paper, instead of invoking Dark Energy, we try and fit various cosmological observations with a large Gpc scale under-dense region (Void) which is modeled by a Lemaitre-Tolman-Bondi metric that at large distances becomes a homogeneous FLRW metric. We improve on previous analyses by allowing for nonzero overall curvature, accurately computing the distance to the last-scattering surface and the observed scale of the Baryon Acoustic peaks, and investigating important effects that could arise from having nontrivial Void density profiles. We mainly focus on the WMAP 7-yr data (TT and TE), Supernova data (SDSS SN), Hubble constant measurements (HST) and Baryon Acoustic Oscillation data (SDSS and LRG). We find that the inclusion of a nonzero overall curvature drastically improves the goodness of fit of the Void model, bringing it very close to that of a homogeneous universe containing Dark Energy, while by varying the profile one can increase the value of the local Hubble parameter which has been a challenge for these models. We also try to gauge how well our model can fit the large-scale-structure data, but a comprehensive analysis will require the knowledge of perturbations on LTB metrics. The model is consistent with the CMB dipole if the observer is about 15 Mpc off the centre of the Void. Remarkably, such an off-center position may be able to account for the recent anomalous measurements of a large bulk flow from kSZ data. Finally we provide several analytical approximations in different regimes for the LTB metric, and a numerical module for CosmoMC, thus allowing for a MCMC exploration of the full parameter space.Comment: 70 pages, 12 figures, matches version accepted for publication in JCAP. References added, numerical values in tables changed due to minor bug, conclusions unaltered. Numerical module available at http://web.physik.rwth-aachen.de/download/valkenburg

    Narrative Exposure Therapy for Posttraumatic Stress Disorder associated with repeated interpersonal trauma in patients with Severe Mental Illness: a mixed methods design

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    Background: In the Netherlands, most patients with severe mental illness (SMI) receive flexible assertive community treatment (FACT) provided by multidisciplinary community mental health teams. SMI patients with comorbid posttraumatic stress disorder (PTSD) are sometimes offered evidence-based trauma-focused treatment like eye movement desensitization reprocessing or prolonged exposure. There is a large amount of evidence for the effectiveness of narrative exposure therapy (NET) within various vulnerable patient groups with repeated interpersonal trauma. Some FACT-teams provide NET for patients with comorbid PTSD, which is promising, but has not been specifically studied in SMI patients. Objectives: The primary aim is to evaluate NET in SMI patients with comorbid PTSD associated with repeated interpersonal trauma to get insight into whether (1) PTSD and dissociative symptoms changes and (2) changes occur in the present SMI symptoms, care needs, quality of life, global functioning, and care consumption. The second aim is to gain insight into patients’ experiences with NET and to identify influencing factors on treatment results. Methods: This study will have a mixed methods convergent design consisting of quantitative repeated measures and qualitative semi-structured in-depth interviews based on Grounded Theory. The study population will include adult SMI outpatients (n=25) with comorbid PTSD and receiving NET. The quantitative study parameters will be existence and severity of PTSD, dissociative, and SMI symptoms; care needs; quality of life; global functioning; and care consumption. In a longitudinal analysis, outcomes will be analyzed using mixed models to estimate the difference in means between baseline and repeated measurements. The qualitative study parameters will be experiences with NET and perceived factors for success or failure. Integration of quantitative and qualitative results will be focused on interpreting how qualitative results enhance the understanding of quantitative outcomes. Discussion: The results of this study will provide more insight into influencing factors for clinical changes in this population

    Machine Learning in Automated Text Categorization

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    The automated categorization (or classification) of texts into predefined categories has witnessed a booming interest in the last ten years, due to the increased availability of documents in digital form and the ensuing need to organize them. In the research community the dominant approach to this problem is based on machine learning techniques: a general inductive process automatically builds a classifier by learning, from a set of preclassified documents, the characteristics of the categories. The advantages of this approach over the knowledge engineering approach (consisting in the manual definition of a classifier by domain experts) are a very good effectiveness, considerable savings in terms of expert manpower, and straightforward portability to different domains. This survey discusses the main approaches to text categorization that fall within the machine learning paradigm. We will discuss in detail issues pertaining to three different problems, namely document representation, classifier construction, and classifier evaluation.Comment: Accepted for publication on ACM Computing Survey

    Study of J/psi decays to Lambda Lambdabar and Sigma0 Sigma0bar

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    The branching ratios and Angular distributions for J/psi decays to Lambda Lambdabar and Sigma0 Sigma0bar are measured using BESII 58 million J/psi.Comment: 11 pages, 5 figure
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