244 research outputs found
Tail and ear necrosis in piglets of sows with increased weight loss over the suckling period.
A farm belonging to a Swiss sow pool system reported increased cases of necrosis on the base of the tail or ears in their piglets. Therefore, herd examination was performed in February 2021, and it was found that about half of all examined litters included piglets with necrosis of different locations, and that the sows of these piglets were rather thin. Upon instruction, the farmer then documented the body condition score (BCS) and weight before farrowing and after weaning, and the number of liveborn piglets affected by necrosis of the tail or ear of the next four farrowing batches. In total, data of 97 sows with 1214 liveborn piglets were evaluated. Sows were retrospectively allocated into two groups: Those with piglets with ear and/or tail necrosis (NE), and those without (WN). Of the 97 litters, 40 included piglets with necrosis, with 28 of them having piglets only with tail necrosis, 8 only with ear necrosis, and 4 litters included piglets with both types of necrosis. The group NE lost significantly more weight and BCS points over the suckling period than the group WN, with a tendency of having a lower BCS after weaning (2,0 vs. 2,25/5,0). Blood samples of five sows were analyzed and tested positive for the Fusarium mycotoxin deoxynivalenol (DON). It could be possible that the sows previously consumed DON contaminated feed, which was then stored in their fat tissue, and released again into the blood stream during increased weight loss. Since DON can be transferred from the sow to her piglets during gestation or lactation, this release might have affected the piglets, leading to tail or ear necrosis. However, causative studies are needed to confirm this hypothesis
Dust depletion of of metals from local to distant galaxies II: Cosmic dust-to-metal ratio and dust composition
The evolution of the cosmic dust content and the cycle between metals and
dust in the interstellar medium (ISM) play a fundamental role in galaxy
evolution. The chemical enrichment of the Universe can be traced through the
evolution of the dust-to-metals ratio (DTM) and the dust-to-gas ratio (DTG)
with metallicity. We use a novel method to determine mass estimates of the DTM,
DTG and dust composition based on our previous measurements of the depletion of
metals in different environments (the Milky Way, the Magellanic Clouds, and
damped Lyman- absorbers, DLAs, toward quasars and towards gamma-ray
bursts, GRBs), which were calculated from the relative abundances of metals in
the ISM through absorption-line spectroscopy column densities observed mainly
from VLT/UVES and X-shooter, and HST/STIS. We derive the dust extinction from
the estimated dust depletion () and compare with the
from extinction. We find that the DTM and DTG ratios increase with metallicity
and with the dust tracer [Zn/Fe]. This suggests that grain growth in the ISM is
a dominant process of dust production. The increasing trend of the DTM and DTG
with metallicity is in good agreement with a dust production and evolution
model. Our data suggest that the stellar dust yield is much lower than the
metal yield and thus that the overall amount of dust in the warm neutral medium
that is produced by stars is much lower. We find that is
overall lower than for the Milky Way and a few Magellanic
Clouds lines of sight, a discrepancy that is likely related to the presence of
carbonaceous dust. We show that the main elements that contribute to the dust
composition are, O, Fe, Si, Mg, C, S, Ni and Al for all the environments.
Abundances at low dust regimes suggest the presence of pyroxene and metallic
iron in dust.Comment: Accepted for publication in A&A. Abstract abridge
Impact of Ultra High Definition on Visual Attention
Ultra high definition (UHD) TV is rapidly replacing high definition (HD) TV but little is known of its effects on human visual attention. However, a clear understanding of this effect is important, since accurate models, evaluation methodologies, and metrics for visual attention are essential in many areas, including image and video compression, camera and displays manufacturing, artistic content creation, and advertisement. In this paper, we address this problem by creating a dataset of UHD resolution images with corresponding eye-tracking data, and we show that there is a statistically significant difference between viewing strategies when watching UHD and HD contents. Furthermore, by evaluating five representative computational models of visual saliency, we demonstrate the decrease in models' accuracies on UHD contents when compared to HD contents. Therefore, to improve the accuracy of computational models for higher resolutions, we propose a segmentation-based resolution-adaptive weighting scheme. Our approach demonstrates that taking into account information about resolution of the images improves the performance of computational models
Analytic frameworks for assessing dialogic argumentation in online learning environments
Over the last decade, researchers have developed sophisticated online learning environments to support students engaging in argumentation. This review first considers the range of functionalities incorporated within these online environments. The review then presents five categories of analytic frameworks focusing on (1) formal argumentation structure, (2) normative quality, (3) nature and function of contributions within the dialog, (4) epistemic nature of reasoning, and (5) patterns and trajectories of participant interaction. Example analytic frameworks from each category are presented in detail rich enough to illustrate their nature and structure. This rich detail is intended to facilitate researchers’ identification of possible frameworks to draw upon in developing or adopting analytic methods for their own work. Each framework is applied to a shared segment of student dialog to facilitate this illustration and comparison process. Synthetic discussions of each category consider the frameworks in light of the underlying theoretical perspectives on argumentation, pedagogical goals, and online environmental structures. Ultimately the review underscores the diversity of perspectives represented in this research, the importance of clearly specifying theoretical and environmental commitments throughout the process of developing or adopting an analytic framework, and the role of analytic frameworks in the future development of online learning environments for argumentation
Rituximab in B-Cell Hematologic Malignancies: A Review of 20 Years of Clinical Experience
Rituximab is a human/murine, chimeric anti-CD20 monoclonal antibody with established efficacy, and a favorable and well-defined safety profile in patients with various CD20-expressing lymphoid malignancies, including indolent and aggressive forms of B-cell non-Hodgkin lymphoma. Since its first approval 20 years ago, intravenously administered rituximab has revolutionized the treatment of B-cell malignancies and has become a standard component of care for follicular lymphoma, diffuse large B-cell lymphoma, chronic lymphocytic leukemia, and mantle cell lymphoma. For all of these diseases, clinical trials have demonstrated that rituximab not only prolongs the time to disease progression but also extends overall survival. Efficacy benefits have also been shown in patients with marginal zone lymphoma and in more aggressive diseases such as Burkitt lymphoma. Although the proven clinical efficacy and success of rituximab has led to the development of other anti-CD20 monoclonal antibodies in recent years (e.g., obinutuzumab, ofatumumab, veltuzumab, and ocrelizumab), rituximab is likely to maintain a position within the therapeutic armamentarium because it is well established with a long history of successful clinical use. Furthermore, a subcutaneous formulation of the drug has been approved both in the EU and in the USA for the treatment of B-cell malignancies. Using the wealth of data published on rituximab during the last two decades, we review the preclinical development of rituximab and the clinical experience gained in the treatment of hematologic B-cell malignancies, with a focus on the well-established intravenous route of administration. This article is a companion paper to A. Davies, et al., which is also published in this issue
Shocks to Bank Lending, Risk-Taking, Securitization, and Their Role for U.S. Business Cycle Fluctuations
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