Energy Status of Steers Dictates Effectiveness of Glycerol Inclusion in High-Roughage and High-Concentrate Feedlot Diets

The objective of this research was to determine how to use glycerol as an effective source of energy in ruminant diets. Steer calves were used in a 56 d backgrounding study (n=128; Initial BW=340 ± 15 kg) and 105 d finishing study (n=120; Initial BW=420 ± 20 kg). Dietary treatments during backgrounding included 0, 8, 16, and 24% glycerol replacing corn silage in corn silage-based diets. Steers continued on within relative levels of dietary glycerol with finishing diets consisting of 0, 5, 10, and 15% glycerol replacing corn. Cumulative DMI, ADG, and G:F increased linearly (

scite: The next generation of citations

Key points While the importance of citation context has long been recognized, simple citation counts remain as a crude measure of importance. Providing citation context should support the publication of careful science instead of headline‐grabbing and salami‐sliced non‐replicable studies. Machine learning has enabled the extraction of citation context for the first time, and made the classification of citation types at scale possible

Household Disruption and Sexual Victimization Among Young South Africans.

This dissertation comprises two empirical articles investigating the influences of household-level disruption and sexual victimization on the sexual and reproductive behavior of young South Africans, and a third identifying methodological limitations of research on sexual victimization. In particular, the empirical articles examine whether: 1) Household-level disruptions are associated with increases in young people’s risky sexual behavior and whether disruptions accumulate to produce greater influences; and whether 2) Sexual victimization increases the likelihood of adolescent pregnancy. Each uses a multi-disciplinary perspective to identify and address important gaps in the literature and the analysis on sexual victimization corrects significant methodological shortcomings of previous research. Taken together, the articles underscore the need for more and better research on the influences of trauma and disruption on the lives of young people and provide some direction for these efforts. Results indicate that young people experiencing a single household-level disruption or multiple disruptions do not demonstrate increased sexual activity or involvement with older partners, nor are they less likely to use condoms. I discuss data limitations that may explain these findings and suggest improvements to future research. Conversely, experiencing some forms of sexual victimization is associated with an increased hazard of adolescent pregnancy. Unexpectedly, however, respondents who were the most severely sexually victimize were no more likely to become pregnant during adolescence than respondents who were not sexually victimized. These results suggest that existing theories may need modification to account for a wider range of individual behaviors. The third article provides a substantive methodological critique of existing research on sexual victimization and offers examples of how limitations and inconsistencies in definitions, methods, and measures may affect the research findings and impede the accumulation of knowledge. In particular, it identifies methodological shortcomings that undermine the validity of previous findings, including the lack of attention to racial/ethnic diversity and other sample selectivity, problematic assumptions underlying survey questionnaires, and issues related to temporal ordering and confounding variables. Furthermore, it describes some methodological and analytical decisions made by scholars of this research that make it difficult to compare findings across studies and determine the state of knowledge on the topic.Ph.D.SociologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/60663/1/susanml_1.pd

Sequence and structural evolution of the KsgA/Dim1 methyltransferase family

<p>Abstract</p> <p>Background</p> <p>One of the 60 or so genes conserved in all domains of life is the <it>ksgA/dim1 </it>orthologous group. Enzymes from this family perform the same post-transcriptional nucleotide modification in ribosome biogenesis, irrespective of organism. Despite this common function, divergence has enabled some family members to adopt new and sometimes radically different functions. For example, in <it>S. cerevisiae </it>Dim1 performs two distinct functions in ribosome biogenesis, while human mtTFB is not only an rRNA methyltransferase in the mitochondria but also a mitochondrial transcription factor. Thus, these proteins offer an unprecedented opportunity to study evolutionary aspects of structure/function relationships, especially with respect to our recently published work on the binding mode of a KsgA family member to its 30S subunit substrate. Here we compare and contrast KsgA orthologs from bacteria, eukaryotes, and mitochondria as well as the paralogous ErmC enzyme.</p> <p>Results</p> <p>By using structure and sequence comparisons in concert with a unified ribosome binding model, we have identified regions of the orthologs that are likely related to gains of function beyond the common methyltransferase function. There are core regions common to the entire enzyme class that are associated with ribosome binding, an event required in rRNA methylation activity, and regions that are conserved in subgroups that are presumably related to non-methyltransferase functions.</p> <p>Conclusion</p> <p>The ancient protein KsgA/Dim1 has adapted to cellular roles beyond that of merely an rRNA methyltransferase. These results provide a structural foundation for analysis of multiple aspects of ribosome biogenesis and mitochondrial transcription.</p

Reinventing Social Work Education and Service Delivery in Rural Areas: An Interdisciplinary Model for Serving Vulnerable Populations

This article presents an interprofessional case study approach to serving the social service and health needs of vulnerable persons living rural communities. This project, the Congregational Social Work Education Initiative (CSWEI), is funded by a health care foundation. Persons in rural areas are often at risk for poverty, homelessness and lack of access to needed health and social services. The case study demonstrates the opportunities for collaboration between professional social work, religiously affiliated organizations (RAOs) and nursing in order to reduce health and mental health disparities among residents in rural areas

scite: A Smart Citation Index that Displays the Context of Citations and Classifies Their Intent Using Deep Learning

Citation indices are tools used by the academic community for research and research evaluation that aggregate scientific literature output and measure impact by collating citation counts. Citation indices help measure the interconnections between scientific papers but fall short because they fail to communicate contextual information about a citation. The use of citations in research evaluation without consideration of context can be problematic because a citation that presents contrasting evidence to a paper is treated the same as a citation that presents supporting evidence. To solve this problem, we have used machine learning, traditional document ingestion methods, and a network of researchers to develop a “smart citation index” called scite, which categorizes citations based on context. Scite shows how a citation was used by displaying the surrounding textual context from the citing paper and a classification from our deep learning model that indicates whether the statement provides supporting or contrasting evidence for a referenced work, or simply mentions it. Scite has been developed by analyzing over 25 million full-text scientific articles and currently has a database of more than 880 million classified citation statements. Here we describe how scite works and how it can be used to further research and research evaluation

Assessing and Improving the Local Added Value of WRF for Wind Downscaling

Limited area models (LAMs) are widely used tools to downscale the wind speed forecasts issued by general circulation models. However, only a few studies have systematically analyzed the value added by the LAMs to the coarser-resolution-model wind. The goal of the present work is to investigate how added value depends on the resolution of the driving global model. With this aim, the Weather Research and Forecasting (WRF) Model was used to downscale three different global datasets (GFS, ERA-Interim, and NCEP?NCAR) to a 9-km-resolution grid for a 1-yr period. Model results were compared with a large set of surface observations, including land station and offshore buoy data. Substantial biases were found at this resolution over mountainous terrain, and a slight modification to the subgrid orographic drag parameterization was introduced to alleviate the problem. It was found that, at this resolution, WRF is able to produce significant added value with respect to the NCEP?NCAR reanalysis and ERA-Interim but only a small amount of added value with respect to GFS forecasts. Results suggest that, as model resolution increases, traditional skill scores tend to saturate. Thus, adding value to high-resolution global models becomes significantly more difficult.The authors thank Puertos del Estado (Spanish National Ports and Harbour Authority) and AEMET (Spanish Meteorological Agency) for providing buoy and land observational records. This work was partly supported by the projects EXTREMBLES (CGL2010-21869) and CORWES (GL2010-22158-C02-01), funded by the Spanish R&D program. The WRF simulations performed in this study were managed by WRF4G, which is an open-source tool funded by the Spanish government and cofunded by the European Regional Development Fund under Grant CGL2011-28864

Scintillation proximity assay for measurement of RNA methylation

Methylation of RNA by methyltransferases is a phylogenetically ubiquitous post-transcriptional modification that occurs most extensively in transfer RNA (tRNA) and ribosomal RNA (rRNA). Biochemical characterization of RNA methyltransferase enzymes and their methylated product RNA or RNA–protein complexes is usually done by measuring the incorporation of radiolabeled methyl groups into the product over time. This has traditionally required the separation of radiolabeled product from radiolabeled methyl donor through a filter binding assay. We have adapted and optimized a scintillation proximity assay (SPA) to replace the more costly, wasteful and cumbersome filter binding assay and demonstrate its utility in studies of three distinct methyltransferases, RmtA, KsgA and ErmC’. In vitro, RmtA and KsgA methylate different bases in 16S rRNA in 30S ribosomal particles, while ErmC’ most efficiently methylates protein-depleted or protein-free 23S rRNA. This assay does not utilize engineered affinity tags that are often required in SPA, and is capable of detecting either radiolabeled RNA or RNA–protein complex. We show that this method is suitable for quantitating extent of RNA methylation or active RNA methyltransferase, and for testing RNA-methyltransferase inhibitors. This assay can be carried out with techniques routinely used in a typical biochemistry laboratory or could be easily adapted for a high throughput screening format