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71.
Sarcoids, the most common tumor of the horse, are fibroblastic, wart-like skin lesions that show variable manifestations. They are often invasive and recurrent, although they do not fulfill all criteria of malignancy. Due to their anatomic location, these tumors can sometimes cause loss of use of the horse. There is very strong evidence that sarcoids are caused by viruses closely related or identical to bovine papilloma viruses, and genetic studies have shown associations between genes in or near the equine major histocompatibility complex (MHC) and susceptibility to sarcoid. Several types of treatments have been successful in treating sarcoids, although the response to therapy is not consistent. Current treatment of sarcoids primarily involves antitumor therapy, but the development of preventative measures in the future may be directed against the causative papilloma virus. Sarcoid continues to be an important clinical entity for the equine practitioner. 相似文献
72.
Julie S. Hui Matthew W. Easterday Elizabeth M. Gerber 《Human-Computer Interaction》2019,34(4):328-378
Supporting learning in online communities is an important direction for the future of human–computer interaction as people increasingly leverage social technologies to support professional growth and development. However, few have studied how people leverage the socio-technical affordances of online informal workplace communities to develop professional skills in the absence of dedicated expert guidance. We draw from theories of apprenticeship to introduce an emergent theory of distributed apprenticeship, which outlines how community expectations of transparency and mutual support allow for instruction to be directed by a distributed network of nonexperts. We develop distributed apprenticeship through a qualitative study of crowdfunding entrepreneurs, where novices leverage social interactions with community members to develop a wide range of entrepreneurial skills. We then generalize distributed apprenticeship to other workplace contexts and provide design implications for online communities where people develop professional skills with minimal dedicated formal guidance. 相似文献
73.
Hypermobility of joints and spine is a consequence of abnormal laxity of ligaments, joint capsules and intervertebral discs. Hypermobility per se is a state, not a disease. However, it may lead to generalized arthralgia or localized symptoms (frequent ankle sprains, knee effusions, dislocations of the shoulders of recurrent episodes of back pain). These events may occur even after minor strains. Young women are preferentially affected. The term "hypermobility syndrome" is defined as a combination of hypermobility with arthralgia, low back pain, frequent dislocation or sprains. It is often the result of a hereditary disorder of connective tissue. Individuals with hypermobility are at increased risk for premature osteoarthrosis or polytopic disc degeneration of the spine. However, the vast majority of hyperlax individuals are free of symptoms. Those with symptoms who do not develop osteoarthrosis or disc degeneration usually experience spontaneous improvement with increasing age, thus losing their juvenile hyperlaxity. This usually occurs between the ages of thirty and forty. The present review article also provides guidelines for management and patient information. 相似文献
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75.
Bernd M. Linke Thomas Gerber Ansgar Hatscher Ilaria Salvatori Iñigo Aranguren Maribel Arribas 《Metallurgical and Materials Transactions A》2018,49(1):54-65
Based on 22MnB5 hot stamping steel, three model alloys containing 0.5, 0.8, and 1.5 wt pct Si were produced, heat treated by quenching and partitioning (Q&P), and characterized. Aided by DICTRA calculations, the thermal Q&P cycles were designed to fit into industrial hot stamping by keeping partitioning times ≤ 30 seconds. As expected, Si increased the amount of retained austenite (RA) stabilized after final cooling. However, for the intermediate Si alloy the heat treatment exerted a particularly pronounced influence with an RA content three times as high for the one-step process compared to the two-step process. It appeared that 0.8 wt pct Si sufficed to suppress direct cementite formation from within martensite laths but did not sufficiently stabilize carbon-soaked RA at higher temperatures. Tensile and bending tests showed strongly diverging effects of austenite on ductility. Total elongation improved consistently with increasing RA content independently from its carbon content. In contrast, the bending angle was not impacted by high-carbon RA but deteriorated almost linearly with the amount of low-carbon RA. 相似文献
76.
Gerber BS Pagcatipunan M Smith EV Basu SS Lawless KA Smolin LI Berbaum ML Brodsky IG Eiser AR 《Journal of applied measurement》2006,7(1):55-73
The purpose of this research was to develop survey instruments to evaluate diabetes knowledge and self-efficacy in a diverse population, and investigate the psychometric properties of data obtained with these instruments using Rasch measurement. Two-hundred and fifty-five urban-dwelling participants with diabetes were recruited to complete surveys through independent interviews. To evaluate the association of health literacy on metabolic control, formal literacy and hemoglobin A1c fingerstick testing were performed. Rasch analysis of the data yielded item and person calibrations for self-efficacy and knowledge, with variable maps created to provide both norm and criterion-referenced interpretations. Knowledge scale person separation reliability was 0.50 and item separation reliability was 0.98; while self-efficacy scale person separation reliability was 0.72 with item separation reliability of 0.92. Statistically significant partial correlations were observed between knowledge and health literacy (r = 0.41, p<.001), and self-efficacy and hemoglobin A1c (r = -0.33, p<.001). However, there was no correlation between diabetes knowledge and hemoglobin A1c (r = 0.035, p = 0.29), or health literacy and A1c (r = 0.022, p = 0.36). Diabetes knowledge varied, with non-English speaking individuals having lower measures than English speakers (t(252) = -4.86, p<.001). Non-English speaking individuals also had lower self-efficacy measures than English speakers (t(251) = -2.68, p = .008). Current knowledge deficits and perceptions of self-management may be estimated visually through variable mapping, which may help in individualizing informational needs for people with diabetes. 相似文献
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78.
Force microscopy experiments with the pendulum geometry are performed with attonewton sensitivity (Rugar et al 2004 Nature 43 329). Single-crystalline cantilevers with sub-millinewton spring constants were annealed under ultrahigh-vacuum conditions. It is found that annealing with temperatures below 500?°C can improve the quality factor by an order of magnitude. The high force sensitivity of these ultrasoft cantilevers is used to characterize small magnetic and superconductive particles, which are mounted on the end of the cantilever. Their magnetic properties are analysed in magnetic fields as a function of temperature. The transition of a superconducting sample mounted on a cantilever is measured by the detection of frequency shifts. An increase of dissipation is observed below the critical temperature. The magnetic moment of ferromagnetic particles is determined by real time frequency detection with a phase-locked loop (PLL) as a function of the magnetic field. The dissipation between the probing tip and the sample is another important ingredient for ultrasensitive force measurements. It is found that dissipation increases at separations of 30?nm. The origins of this type of dissipation are poorly understood. However, it is predicted theoretically that adsorbates can increase this dissipation channel (Volokitin and Persson 2005 Phys.?Rev.?Lett. 94 086104). First experiments are performed under ultrahigh vacuum to investigate this type of dissipation. Long-range dissipation is closely related to long-range forces. The distance dependence of the contact potential is found to be an important aspect. 相似文献
79.
80.
Jones RC Gerber SI Diaz PS Williams LL Dennis SB Parish ES Paul WS 《Journal of food protection》2004,67(3):616-623
Local health departments that investigate foodborne disease outbreaks do not have adequate guidelines for collecting data that could be used to estimate dose-response relationships, a key component of hazard characterization in quantitative microbial risk assessment. To meet this need, criteria and a questionnaire template for the collection of appropriate dose-response data in the context of outbreaks were developed and applied in the investigation of a point-source outbreak linked to Salmonella serotype Enteritidis in a salmon entrée in February 2000. In this outbreak, the attack rate and risk of hospitalization increased with the amount of salmon entrée consumed, and detailed data were obtained on illness severity measures and host susceptibility factors. Local health departments might consider broadening investigations to include the collection of additional data when investigating outbreaks that have met a specific set of conditions. These data could provide information needed by federal regulatory agencies and other organizations for quantitative microbial risk assessment. Intensive investigations of outbreaks could prevent future illnesses by providing information needed to develop approaches to minimizing risk. 相似文献