10,061 research outputs found
Aligning and positioning device Patent
Description of device for aligning stacked sheets of paper for repetitive cuttin
High reliability bond program using small diameter aluminum wire
The program was undertaken to characterize the performance of small diameter aluminum wire ultrasonically bonded to conductors commonly encountered in hybrid assemblies, and to recommend guidelines for improving this performance. Wire, 25.4, 38.1 and 50.8 um (1, 1.5 and 2 mil), was used with bonding metallization consisting of thick film gold, thin film gold and aluminum as well as conventional aluminum pads on semiconductor chips. The chief tool for evaluating the performance was the double bond pull test in conjunction with a 72 hour - 150 C heat soak and -65 C to +150 C thermal cycling. In practice the thermal cycling was found to have relatively little effect compared to the heat soak. Pull strength will decrease after heat soak as a result of annealing of the aluminum wire; when bonded to thick film gold, the pull strength decreased by about 50% (weakening of the bond interface was the major cause of the reduction). Bonds to thin film gold lost about 30 - 40% of their initial pull strenth; weakening of the wire itself at the bond heel was the predominant cause. Bonds to aluminum substrate metallization lost only about 22%. Bonds between thick and thin film gold substrate metallization and semiconductor chips substantiated the previous conclusions but also showed that in about 20 to 25% of the cases, bond interface failure occurred at the semiconductor chip
Adjustable cutting guide aligns and positions stacks of material
Adjustable guide tool aligns and positions stacks of material for cutting at various angles. The device adapts its shape to stacks of any corner angle, adjusts to any cutting angle, and quickly aligns the stacks for repeated cutting. With this device, an operator need not place his hands under the knife during alignment
Development of Multiple Polymorphic Microsatellite Markers for Ceratina calcarata (Hymenoptera: Apidae) Using Genome-Wide Analysis
The small carpenter bee, Ceratina calcarata (Robertson), is a widespread native pollinator across eastern North America. The behavioral ecology and nesting biology of C. calcarata has been relatively well-studied and the species is emerging as a model organism for both native pollinator and social evolution research. C. calcarata is subsocial: reproductively mature females provide extended maternal care to their brood. As such, studies of C. calcarata may also reveal patterns of relatedness and demography unique to primitively social Hymenoptera. Here, we present 21 microsatellite loci, isolated from the recently completed C. calcarata genome. Screening in 39 individuals across their distribution revealed that no loci were in linkage disequilibrium, nor did any deviate significantly from Hardy-Weinberg following sequential Bonferroni correction. Allele count ranged from 2 to 14, and observed and expected heterozygosities ranged from 0.08 to 0.82 (mean 0.47) and 0.26 to 0.88 (mean 0.56), respectively. These markers will enable studies of population-wide genetic structuring across C. calcarata’s distribution. Such tools will also allow for exploration of between and within-colony relatedness in this subsocial native pollinator
Further steps of hepatic stimulatory substance purification
The hepatic stimulatory substance (HSS) extracted from weanling rat livers was purified 381,000-fold using chromatographic techniques including nondissociating polyacrylamide gel electrophoresis (nondenaturing PAGE). The activity of this highly purified HSS, named Acr-F4, was assessed in two in vivo models. In 40% hepatectomized rats, it produced a fivefold increase in the proliferative rate normally seen following this partial hepatectomy. In Eck fistula dogs, the level of base increase in hepatocyte renewal was amplified threefold by an infusion of Acr-F4 (50 ng/kg/day). Acr-F4 had no influence on the regenerative response of the kidney following a unilateral nephrectomy or of the bowel following a 40% resection of the small bowel. On the basis of these findings, it can be concluded that HSS (Acr-F4) has a high biological activity and is organ specific. © 1991 Plenum Publishing Corporation
Gastrointestinal and metabolic problems associated with immunosuppression with either CyA or FK 506 in liver transplantation
Enhanced Anandamide Plasma Levels in Patients with Complex Regional Pain Syndrome following Traumatic Injury: A Preliminary Report
The complex regional pain syndrome (CRPS) is a disabling neuropathic pain condition that may develop following injuries of the extremities. The pathogenesis of this syndrome is not clear; however, it includes complex interactions between the nervous and the immune system resulting in chronic inflammation, pain and trophic changes. This interaction may be mediated by chronic stress which is thought to activate the endogenous cannabinoid (endocannabinoid) system (ECS). We conducted an open, prospective, comparative clinical study to determine plasma level of the endocannabinoid anandamide by high-performance liquid chromatography and a tandem mass spectrometry system in 10 patients with CRPS type I versus 10 age- and sex-matched healthy controls. As compared to healthy controls, CRPS patients showed significantly higher plasma concentrations of anandamide. These results indicate that the peripheral ECS is activated in CRPS. Further studies are warranted to evaluate the role of the ECS in the limitation of inflammation and pain. Copyright (C) 2009 S. Karger AG, Base
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