57 research outputs found
On some invariant ideals, and on extension of differentiations to seminormalization
AbstractLet A be a noetherian integral domain, D=(1,D1,…,Di…) be a differentation of A, and B be a ring such that A⊂B⊂Ā. In the paper we mainly prove (whenever Ā is finite over A): (a) if α is the conductor of A in B, then A√α is D-invariant. (b) D extends to the seminormalization +A of A in Ā
Body weight prediction using body size measurements in Fleckvieh, Holstein, and Brown Swiss dairy cows in lactation and dry periods
The objective of this study was to predict cows'
body weight from body size measurements and other animal data in the
lactation and dry periods. During the whole year 2014, 6306 cows (on
167Â commercial Austrian dairy farms) were weighed at each routine performance
recording and body size measurements like heart girth (HG), belly girth (BG),
and body condition score (BCS) were recorded. Data on linear traits like hip
width (HW), stature, and body depth were collected three times a year. Cows
belonged to the genotypes Fleckvieh (and Red Holstein crosses), Holstein, and
Brown Swiss. Body measurements were tested as single predictors and in
multiple regressions according to their prediction accuracy and their
correlations with body weight. For validation, data sets were split randomly
into independent subsets for estimation and validation. Within the prediction
models with a single body measurement, heart girth influenced relationship
with body weight most, with a lowest root mean square error (RMSE) of
39.0 kg, followed by belly girth (39.3 kg) and hip width (49.9 kg). All
other body measurements and BCS resulted in a RMSE of higher than 50.0Â kg.
The model with heart and belly girth (ModelHG BG) reduced RMSE to
32.5 kg, and adding HW reduced it further to
30.4 kg (ModelHG BG HW). As RMSE and the coefficient of
determination improved, genotype-specific regression coefficients for body
measurements were introduced in addition to the pooled ones. The most
accurate equations, ModelHG BG and ModelHG BG HW,
were validated separately for the lactation and dry periods. Root mean square
prediction error (RMSPE) ranged between 36.5 and 37.0 kg
(ModelHG BG HW, ModelHG BG, lactation) and 39.9 and
41.3 kg (ModelHG BG HW, ModelHG BG, dry period).
Accuracy of the predictions was evaluated by decomposing the mean square
prediction error (MSPE) into error due to central tendency, error due to
regression, and error due to disturbance. On average, 99.6 % of the
variance between estimated and observed values was caused by disturbance,
meaning that predictions were valid and without systematic estimation error.
On the one hand, this indicates that the chosen traits sufficiently depicted
factors influencing body weight. On the other hand, the data set was very
heterogeneous and large. To ensure high prediction accuracy, it was necessary
to include body girth traits for body weight estimation.</p
A meta-analysis of N-acetylcysteine in contrast-induced nephrotoxicity: unsupervised clustering to resolve heterogeneity
<p>Abstract</p> <p>Background</p> <p>Meta-analyses of N-acetylcysteine (NAC) for preventing contrast-induced nephrotoxicity (CIN) have led to disparate conclusions. Here we examine and attempt to resolve the heterogeneity evident among these trials.</p> <p>Methods</p> <p>Two reviewers independently extracted and graded the data. Limiting studies to randomized, controlled trials with adequate outcome data yielded 22 reports with 2746 patients.</p> <p>Results</p> <p>Significant heterogeneity was detected among these trials (<it>I</it><sup>2 </sup>= 37%; <it>p </it>= 0.04). Meta-regression analysis failed to identify significant sources of heterogeneity. A modified L'Abbé plot that substituted groupwise changes in serum creatinine for nephrotoxicity rates, followed by model-based, unsupervised clustering resolved trials into two distinct, significantly different (<it>p </it>< 0.0001) and homogeneous populations (<it>I</it><sup>2 </sup>= 0 and <it>p </it>> 0.5, for both). Cluster 1 studies (<it>n </it>= 18; 2445 patients) showed no benefit (relative risk (RR) = 0.87; 95% confidence interval (CI) 0.68–1.12, <it>p </it>= 0.28), while cluster 2 studies (<it>n </it>= 4; 301 patients) indicated that NAC was highly beneficial (RR = 0.15; 95% CI 0.07–0.33, <it>p </it>< 0.0001). Benefit in cluster 2 was unexpectedly associated with NAC-induced decreases in creatinine from baseline (<it>p </it>= 0.07). Cluster 2 studies were relatively early, small and of lower quality compared with cluster 1 studies (<it>p </it>= 0.01 for the three factors combined). Dialysis use across all studies (five control, eight treatment; <it>p </it>= 0.42) did not suggest that NAC is beneficial.</p> <p>Conclusion</p> <p>This meta-analysis does not support the efficacy of NAC to prevent CIN.</p
Association of plasma microRNA expression with age, genetic background and functional traits in dairy cattle
Abstract A number of blood circulating microRNAs (miRNAs) are proven disease biomarkers and have been associated with ageing and longevity in multiple species. However, the role of circulating miRNAs in livestock species has not been fully studied. We hypothesise that plasma miRNA expression profiles are affected by age and genetic background, and associated with health and production traits in dairy cattle. Using PCR arrays, we assessed 306 plasma miRNAs for effects of age (calves vs mature cows) and genetic background (control vs select lines) in 18 animals. We identified miRNAs which were significantly affected by age (26 miRNAs) and genetic line (5 miRNAs). Using RT-qPCR in a larger cow population (n = 73) we successfully validated array data for 12 age-related miRNAs, one genetic line-related miRNA, and utilised expression data to associate their levels in circulation with functional traits in these animals. Plasma miRNA levels were associated with telomere length (ageing/longevity indicator), milk production and composition, milk somatic cell count (mastitis indicator), fertility, lameness, and blood metabolites linked with body energy balance and metabolic stress. In conclusion, circulating miRNAs could provide useful selection markers for dairy cows to help improve health, welfare and production performance
Systematic genotyping of groups of cows to improve genomic estimated breeding values of selection candidates
Non-AIDS defining cancers in the D:A:D Study-time trends and predictors of survival : a cohort study
BACKGROUND:Non-AIDS defining cancers (NADC) are an important cause of morbidity and mortality in HIV-positive individuals. Using data from a large international cohort of HIV-positive individuals, we described the incidence of NADC from 2004-2010, and described subsequent mortality and predictors of these.METHODS:Individuals were followed from 1st January 2004/enrolment in study, until the earliest of a new NADC, 1st February 2010, death or six months after the patient's last visit. Incidence rates were estimated for each year of follow-up, overall and stratified by gender, age and mode of HIV acquisition. Cumulative risk of mortality following NADC diagnosis was summarised using Kaplan-Meier methods, with follow-up for these analyses from the date of NADC diagnosis until the patient's death, 1st February 2010 or 6 months after the patient's last visit. Factors associated with mortality following NADC diagnosis were identified using multivariable Cox proportional hazards regression.RESULTS:Over 176,775 person-years (PY), 880 (2.1%) patients developed a new NADC (incidence: 4.98/1000PY [95% confidence interval 4.65, 5.31]). Over a third of these patients (327, 37.2%) had died by 1st February 2010. Time trends for lung cancer, anal cancer and Hodgkin's lymphoma were broadly consistent. Kaplan-Meier cumulative mortality estimates at 1, 3 and 5 years after NADC diagnosis were 28.2% [95% CI 25.1-31.2], 42.0% [38.2-45.8] and 47.3% [42.4-52.2], respectively. Significant predictors of poorer survival after diagnosis of NADC were lung cancer (compared to other cancer types), male gender, non-white ethnicity, and smoking status. Later year of diagnosis and higher CD4 count at NADC diagnosis were associated with improved survival. The incidence of NADC remained stable over the period 2004-2010 in this large observational cohort.CONCLUSIONS:The prognosis after diagnosis of NADC, in particular lung cancer and disseminated cancer, is poor but has improved somewhat over time. Modifiable risk factors, such as smoking and low CD4 counts, were associated with mortality following a diagnosis of NADC
Short communication: Genotyping of cows to speed up availability of genomic estimated breeding values for direct health traits in Austrian Fleckvieh (Simmental) cattle—Genetic and economic aspects
Farmer-observed health data around calving—Genetic parameters and association with veterinarian diagnoses in Austrian Fleckvieh cows
Standardization of health data. ICAR guidelines including health key
peer reviewedSystematic improvement of animal health requires knowledge about the status quo and reliable measures to characterize it. In dairy herds, health monitoring has gained importance to ensure sustainable and cost-efficient milk production in accordance with public expectations. In this context, standardized recording of health data is essential for comparability and interpretability of health-related analyses, implying the need for generally accepted and clear guidelines. To assist implementation of health monitoring and convey harmonization, the ICAR Functional Traits Working Group has compiled the ICAR guidelines for Recording, Evaluation and Genetic Improvement of Health Traits, which were approved in June 2012. Disease diagnoses and observations of impaired health can be classified as direct health data, providing the basis for targeted approaches to improve the animal health status. Data sources need to be taken into account because of their impact on information content and specificity. The key for health data recording is characterized by a hierarchical structure that makes it possible to record on different levels of detail and includes comprehensive recording options with coverage of all organ systems and types of diseases. Important features are compatibility with other recording systems and broad usability as a reference regardless of specific intentions and contexts of health data collection. Input can range from very specific diagnoses of veterinarians to very general diagnoses or observations by producers, and the unique coding of clearly defined health incidents minimizes the risk of misinterpretations and facilitates analyses of different types of health data. The overall quality and success of health monitoring is substantially influenced byappropriate use of standards and available recording tools, implying the need for tailored support particularly in the implementation phase. In integrated concepts, specific qualifications of professions can be used synergistically to further standardize recording of health data and thereby benefit efficiency of animal health improvement on farm and at the population level
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