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排序方式: 共有271条查询结果,搜索用时 33 毫秒
51.
Reg.-Rat Prof. G. Rupp 《European Food Research and Technology》1919,37(9-12):370-377
52.
Philipp Simons Kierstin P. Torres Jennifer L. M. Rupp 《Advanced functional materials》2021,31(31):2009630
Low-temperature ceramic proton conductors such as ceria are important for applications ranging from sensors and resistive switches to new devices like implantable solid-oxide glucose fuel cells. Spray pyrolysis offers a promising fabrication route for proton-conducting ceria, with direct liquid-to-solid synthesis and control over crystallinity and grain size. To date, there are conflicting reports on ceria's proton conduction mechanism, particularly whether the interior contributes to proton conduction or transport occurs exclusively along a surface water layer. In this work, proton conductivity is observed in sprayed ceria thin films at 125 °C and below. Post-annealed films exhibit higher conductivity than as-deposited films of 3.3 × 10−5 S cm−1 at 25 °C, which is comparable to previous reports and ascribed to the increase in crystallinity and grain size by post-annealing. This indicates that the interior of ceria in fact contributes to proton conduction. Remarkably slow hydration kinetics of ceria are observed, with time-dependent conductivity equilibrating to 9.53 × 10−6 S cm−1 after up to 76 h. This implies kinetics may have suppressed proton conduction in previous studies, explaining the strong fluctuations in reports to date. Slow protonation kinetics must be considered when designing functional ceria ceramics, for example, in electrochemical bio-energy conversion, sensing or neuromorphic computing. 相似文献
53.
We describe nuchal cord changes in four children with os odontoideum who had cervical spine magnetic resonance imaging (MRI) before surgery. In these four children, nuchal cord changes consistent with previous trauma were seen. The presence of the nuchal cord changes supports the concept of trauma as an etiologic factor in these four cases. This study supports trauma as an associated factor in patients with os odontoideum. 相似文献
54.
A 10-year retrospective analysis of invasive mold infections in hospitalized patients was performed to characterize the epidemiology and clinical features of invasive fungal sinusitis. Seventeen cases of invasive mold sinusitis were identified. Eleven cases were caused by Aspergillus flavus, three were caused by unspecified species, and one each was caused by Aspergillus fumigatus, Rhizopus species, and Alternaria species, respectively. Fifteen patients had hematologic malignancies, and two had end-stage liver disease. The most common presenting symptom was periorbital swelling (seven patients). Sinusitis was diagnosed a median of 19 days after admission. Eight patients (47%) survived; six of these patients were treated with both amphotericin B and surgery. Postmortem examination of six patients showed evidence of disseminated disease; the brain was the most common extrapulmonary site (four patients). To our knowledge, this is the largest currently reported series on invasive mold sinusitis; our report extends the information on invasive mold sinusitis and shows that aggressive therapeutic and surgical interventions are needed to prevent rapid progression of disease in immunocompromised patients. 相似文献
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David K Lunt Thomas H Welsh Gary P Rupp Robert W Field H Russell Cross Ann M Miller Homer A Recio Mark F Miller Gary C Smith 《Journal of the science of food and agriculture》1990,51(4):535-544
Ninety heifers sired by Charolais or Red Poll bulls were utilised in two trials involving ovariectomy, ovarian tissue transplants (autografts) andlor an anabolic implant. In trial 1, four treatments were imposed upon 60 heifers: (1) autograft, (2) autograft plus Synovex-H® implant, (3) vaginal ovariectomy plus implant, and (4) intact plus implant. Three replications of five heifers per treatment were fed a finishing diet until heifers weighed approximately 432 kg. Autografed-implanted heifers exhibited a greater average daily gain than non-implanted autografted heifers (P < 0.05). No treatment effects were detected for feed eficiency or dressing percentage. Carcasses from autografted heifers merited higher marbling scores and USDA quality grades than did those of ovariectomised-implanted heifers. Fat thickness tended to be greater for autografted heifers than for heifers in the implant treatment groups (P <0.l0). Non-implanted autografted heifers had smaller ribeye areas, more kidney, pelvic and heart fat, and higher numerical USDA yield grades. Shear force values and taste panel scores for meat favoured non-implanted autografted heifers. In trial 2, 30 heifers were autografted, ovariectomised via high lumbar laparotomy, or left as intact controls. Heifers in trial 2 were fed a finishing diet until heifers reached 1.2 ern average backfat thickness. Intact heifers tended to gain weight more rapidly than did ovariectomised heifers. Ovarian cell types were detected at the graft sites of only four of the 10 autografted heifers upon post-mortem histological examination. Very low levels of oestrogen were present in the fluid aspirated from three of the apparently successful grafts. However, growth rate was not superior for these three heifers. 相似文献
59.
The least mean square (LMS) algorithm is known to converge in the mean and in the mean square. However, during short time periods, the error sequence can blow up and cause severe disturbances, especially for non-Gaussian processes. The paper discusses potential short time unstable behavior of the LMS algorithm for spherically invariant random processes (SIRP) like Gaussian, Laplacian, and K0. The result of this investigation is that the probability for bursting decreases with the step size. However, since a smaller step size also causes a slower convergence rate, one has to choose a tradeoff between convergence speed and the frequence of bursting 相似文献
60.
Baculovirus-dependent expression of membrane-associated and secreted, heavily modified proteins in insect cells often results in low yields. To optimize expression of T1, a heavily glycosylated receptor related to Interleukin-1 receptor type I, deletion mutants comprising either the heavily glycosylated extracellular domain or the isolated transmembrane and cytoplasmic portions of the T1 receptor were expressed from recombinant baculoviruses. As shown here, the use of a Baculovirus-derived leader sequence (GP67) in combination with an insect cell line with increased secretory capacity resulted in yields of several mg per liter (10(9) cells) of culture of both purified secretory T1 glycoprotein and membrane-associated T1 receptor. 相似文献