2,272 research outputs found

    EFFECTS OF A CRYSTALLOGRAPHIC TRANSFORMATION ON THE PHOTOELECTRIC AND THERMIONIC EMISSION FROM COBALT

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    Spatiotemporal patterns and agro-ecological risk factors for cutaneous and renal glomerular vasculopathy (Alabama Rot) in dogs in the UK

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    Seasonal outbreaks of cutaneous and renal glomerular vasculopathy (CRGV) have been reported annually in UK dogs since 2012, yet the aetiology of the disease remains unknown. The objectives of this study were to explore whether any breeds had an increased or decreased risk of being diagnosed with CRGV, and to report on age and sex distributions of CRGV cases occurring in the UK. Multivariable logistic regression was used to compare 101 dogs diagnosed with CRGV between November 2012 and May 2017 with a denominator population of 446,453 dogs from the VetCompass database. Two Kennel Club breed groups—hounds (odds ratio (OR) 10.68) and gun dogs (OR 9.69)—had the highest risk of being diagnosed with CRGV compared with terriers, while toy dogs were absent from among CRGV cases. Females were more likely to be diagnosed with CRGV (OR 1.51) as were neutered dogs (OR 3.36). As well as helping veterinarians develop an index of suspicion for the disease, better understanding of the signalment risk factors may assist in the development of causal models for CRGV and help identify the aetiology of the disease

    Signalment risk factors for cutaneous and renal glomerular vasculopathy (Alabama rot) in dogs in the UK

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    Seasonal outbreaks of cutaneous and renal glomerular vasculopathy (CRGV) have been reported annually in UK dogs since 2012, yet the aetiology of the disease remains unknown. The objectives of this study were to explore whether any breeds had an increased or decreased risk of being diagnosed with CRGV, and to report on age and sex distributions of CRGV cases occurring in the UK. Multivariable logistic regression was used to compare 101 dogs diagnosed with CRGV between November 2012 and May 2017 with a denominator population of 446,453 dogs from the VetCompass database. Two Kennel Club breed groups—hounds (odds ratio (OR) 10.68) and gun dogs (OR 9.69)—had the highest risk of being diagnosed with CRGV compared with terriers, while toy dogs were absent from among CRGV cases. Females were more likely to be diagnosed with CRGV (OR 1.51) as were neutered dogs (OR 3.36). As well as helping veterinarians develop an index of suspicion for the disease, better understanding of the signalment risk factors may assist in the development of causal models for CRGV and help identify the aetiology of the disease

    Behavior of bulk high-temperature superconductors of finite thickness subjected to crossed magnetic fields

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    Crossed magnetic field effects on bulk high-temperature superconductors have been studied both experimentally and numerically. The sample geometry investigated involves finite-size effects along both (crossed) magnetic field directions. The experiments were carried out on bulk melt-processed Y-Ba-Cu-O (YBCO) single domains that had been pre-magnetized with the applied field parallel to their shortest direction (i.e. the c-axis) and then subjected to several cycles of the application of a transverse magnetic field parallel to the sample ab plane. The magnetic properties were measured using orthogonal pick-up coils, a Hall probe placed against the sample surface and Magneto-Optical Imaging (MOI). We show that all principal features of the experimental data can be reproduced qualitatively using a two-dimensional finite-element numerical model based on an E-J power law and in which the current density flows perpendicularly to the plane within which the two components of magnetic field are varied. The results of this study suggest that the suppression of the magnetic moment under the action of a transverse field can be predicted successfully by ignoring the existence of flux-free configurations or flux-cutting effects. These investigations show that the observed decay in magnetization results from the intricate modification of current distribution within the sample cross-section. It is also shown that the model does not predict any saturation of the magnetic induction, even after a large number (~ 100) of transverse field cycles. These features are shown to be consistent with the experimental data.Comment: 41 pages, 9 figures, accepted in Phys. Rev. B Changes : 8 references added, a few precisions added, some typos correcte

    A Trapped Field of 17.6 T in Melt-Processed, Bulk Gd-Ba-Cu-O Reinforced with Shrink-Fit Steel

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    The ability of large grain, REBa2_{2}Cu3_{3}O7δ_{7-\delta} [(RE)BCO; RE = rare earth] bulk superconductors to trap magnetic field is determined by their critical current. With high trapped fields, however, bulk samples are subject to a relatively large Lorentz force, and their performance is limited primarily by their tensile strength. Consequently, sample reinforcement is the key to performance improvement in these technologically important materials. In this work, we report a trapped field of 17.6 T, the largest reported to date, in a stack of two, silver-doped GdBCO superconducting bulk samples, each of diameter 25 mm, fabricated by top-seeded melt growth (TSMG) and reinforced with shrink-fit stainless steel. This sample preparation technique has the advantage of being relatively straightforward and inexpensive to implement and offers the prospect of easy access to portable, high magnetic fields without any requirement for a sustaining current source.Comment: Updated submission to reflect licence change to CC-BY. This is the "author accepted manuscript" and is identical in content to the published versio

    Maternal body mass index and risk of testicular cancer in male offspring a systematic review and meta analysis

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    OBJECTIVES: To date a number of studies have examined the association between maternal weight and testicular cancer risk although results have been largely inconsistent. This systematic review and meta-analysis investigated the nature of this association. METHODS: Search strategies were conducted in Ovid Medline (1950—2009), Embase (1980—2009), Web of Science (1970—2009), and CINAHL (1937—2009) using keywords for maternal weight (BMI) and testicular cancer. RESULTS: The literature search produced 1,689 hits from which 63 papers were extracted. Only 7 studies met the pre-defined criteria. Random effects meta-analyses were conducted. The combined unadjusted OR (95% CI) of testicular cancer in the highest reported category of maternal BMI compared with the moderate maternal BMI was 0.82 (0.65 – 1.02). The Cochran’s Q P value was 0.83 and the corresponding I(2) was 0%, both indicating very little variability among studies. The combined unadjusted OR (95% CI) for testicular cancer risk in the lowest reported category of maternal BMI compared to a moderate maternal BMI category was 0.92 (0.75 – 1.12). The Cochran’s Q P value was 0.05 and the corresponding I(2) was 54%, indicating evidence of statistical heterogeneity. No association was observed when maternal BMI was treated as a continuous variable. CONCLUSION: This meta-analysis, which included a small number of studies, showed an inverse association between high maternal BMI and testicular cancer risk of borderline statistical significance. Further primary studies with adjustment for appropriate confounders are required

    Rate and temperature effects on the fracture toughness of a rubber-modified epoxy

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    A series of three-point bend fracture toughness tests was performed at various loading rates and temperatures on both rubber-modified and unmodified epoxy specimens. The fracture toughness of the modified samples was determined to be rate- and temperature-dependent. Using time-temperature superposition, an apparent activation energy was determined by shifting the fracture toughness data along the rate axis for each temperature tested. Surprisingly, this apparent activation energy calculated for the rubber-modified epoxy was found to be within 2% of the value of the activation energy determined for the [beta] relaxation peak found from small strain d.m.a. measurements of the unmodified epoxy matrix. This was an unexpected yet interesting correlation. Since shear yielding is the primary mechanism by which this epoxy system is toughened, it can be hypothesized the [beta] relaxation may significantly influence the kinetics of yielding and consequently the fracture tougness of the material. Plastic zone geometry and fracture mechanisms were investigated and were found to support this hypothesis.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/30897/1/0000566.pd

    Effect of TIBA on height, lodging, and yield of soybeans

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    1 online resource (PDF, 2 pages)This archival publication may not reflect current scientific knowledge or recommendations. Current information available from the University of Minnesota Extension: https://www.extension.umn.edu

    Toughening of epoxies through thermoplastic crack bridging

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    The fracture toughness and toughening mechanism of two epoxy matrices containing varying concentrations of pre-formed polyamide-12 particles was investigated. The pre-formed thermoplastic modifier was used to keep the physical and morphological characteristics of the second phase constant while varying the matrix intrinsic toughness to simplify the interpretation of toughening results. We observed that these particles toughened the epoxies through a crack bridging mechanism involving large plastic deformation of the second phase.This mechanism was found to be effective independent of the potential of the matrix for plastic deformation since the increasing fracture toughness was accomplished without significant amounts of plastic deformation in the epoxy matrix. A quantitative model was adapted to account for the increase in toughness due to the crack bridging mechanism. From this model, it was possible to determine the factors which are most important when attempting to toughen a material through thermoplastic crack bridging. A better understanding of the specific factors which influence the efficiency of the crack bridging mechanism enables the fracture properties of brittle materials to be further improved with thermoplastic addition. This was shown to be very important when attempting to enhance the toughness of materials which are believed to be “un-toughenable” by conventional rubber modification, or materials whose other mechanical properties suffer from the addition of elastomeric materials.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44753/1/10853_2004_Article_202802.pd
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