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1.
Jeong-Soo Lee Yang-Kyu Choi Daewon Ha Balasubramanian S. Tsu-Jae King Bokor J. 《Electron Device Letters, IEEE》2003,24(3):186-188
The hydrogen annealing process has been used to improve surface roughness of the Si-fin in CMOS FinFETs for the first time. Hydrogen annealing was performed after Si-fin etch and before gate oxidation. As a result, increased saturation current with a lowered threshold voltage and a decreased low-frequency noise level over the entire range of drain current have been attained. The low-frequency noise characteristics indicate that the oxide trap density is reduced by a factor of 3 due to annealing. These results suggest that hydrogen annealing is very effective for improving device performance and for attaining a high-quality surface of the etched Si-fin. 相似文献
2.
BACKGROUND: The effect of topical corticosteroids after excimer laser photorefractive keratectomy (PRK) remains a matter of some controversy. Refractive effects may be different according to the amount of myopia and timing of instillation. METHODS: Two groups of patients were studied: Study A consisted of 215 eyes (128 patients) with PRK (mean baseline myopia, -6.53 +/- 2.22 D) that received no corticosteroids (No Corticosteroid Group) unless significant regression or corneal haze appeared (Delayed Corticosteroid Group), and in Study B, we randomly assigned eyes to the Initial Corticosteroid Group (mean baseline myopia, -6.39 +/- 1.84 D) or the No/delayed Corticosteroid Group (mean baseline myopia -5.78 +/- 2.02 D). Clinical results after PRK for low-to-moderate and high myopia were compared. RESULTS: In the first group, 70.9% (73 eyes) of moderately myopic eyes (mean, -4.56 +/- 1.10 D) belonged to the No Corticosteroid Group that had a mean refraction of -5.39 +/- 1.77 D. Delayed Corticosteroid Group eyes were more myopic (mean, -7.52 +/- 2.10 D), and showed more severe haze than those in the No Corticosteroid Group. In study B, only in high myopes with more than -6.00 D (mean, -7.76 +/- 1.15 D) did refraction and corneal haze outcomes show significant difference between the Initial Corticosteroid Group and the No/delayed Corticosteroid Group. CONCLUSIONS: The effects of topical corticosteroids after PRK were less in moderate myopes compared to high myopes. Delayed instillation of corticosteroids did not reverse the regression or haze whereas initial instillation showed a beneficial effect on high myopes but not on moderate myopes. 相似文献
3.
OBJECTIVE: We hypothesized that institutionalized patients with dementia, who frequently have feeding problems and require supervised and assisted feeding, would lose more weight during their residency than nondemented, independently functioning residents and have compromised survival. To test this hypothesis, we examined the survival and longitudinal changes in weight of two cohorts of institutionalized residents with dementia and compared these cohorts with a cohort of nondemented residents. We also measured the resting energy expenditures of a subset of the subjects with dementia as an indicator of their energy needs. DESIGN: A longitudinal cohort study with retrospective baseline chart review and subsequent follow-up of monthly weights and mortality over 4 years. SETTING: A 725-bed long-term care institution with specified levels of care. SUBJECTS: Two cohorts of residents with dementia, one consisting of subjects who required total care throughout their institutional stay (n = 31) and another group who did not initially require total care (n = 48); these were compared with a cohort with normal mentation who were functionally independent in their daily activities (n = 26). The total number of subjects was 105. MEASUREMENTS: Demographics, medical problems, and medications by chart review; functional and mental status evaluations; longitudinal monthly weights and mortality for the 48-month study period; and resting energy expenditures by indirect calorimetry. MAIN RESULTS: Residents with dementia had lower weights on admission and throughout their stay than nondemented, independently functioning residents, and they were more likely to have a weight loss of 10 lbs or more at some point during the 4-year study period. However, their mean weights did not change during the study period. The mean survival from admission of those demented residents who died was more than 3 years. Resting energy expenditures of women residents with advanced dementia were 12% lower than predicted from the Harris Benedict equations. CONCLUSION: Dementia is not necessarily associated with unremitting weight loss during institutionalization despite the frequent occurrence of feeding difficulties and temporary weight loss. This may be caused partly by the lower than expected resting energy expenditures and, hence, energy needs of affected residents as their dementia progresses. Demented residents weighed significantly less than nondemented, independently functioning residents throughout their institutional stay. Nevertheless, nursing staff are able to maintain weight and survival for extended periods even in very impaired residents. 相似文献
4.
Seung-Jean Kim In-Joong Ha 《Automatic Control, IEEE Transactions on》2004,49(7):1167-1171
In this note, we consider the existence of a Carathe/spl acute/odory solution in a single-input-single-output nonlinear system with a discontinuous switching feedback controller. The main contribution is to show that if the nonlinear system can be transformed into a global normal form, then we can specify the value of the discontinuous switching feedback controller on the switching hypersurface so that the closed-loop system has a Carathe/spl acute/odory solution. 相似文献
5.
Transglutaminase (TGase), responsible for crosslinking between proteins, is known to be localized exclusively in the egg envelope (chorion) of rainbow trout, Oncorhynchus mykiss, and probably participates in the post-fertilization chorion hardening. We purified the TGase from unfertilized egg chorions by sequential chromatography using SP-Sepharose, Q-Sepharose, and TSK-gel G3000SWXL columns. The purified enzyme was a monomeric protein having the molecular mass of 76 kDa. It promoted incorporation of monodansyl-cadaverine into chorion protein and catalyzed the polymerization of chorion subunit proteins. The effect of various reagents suggested that the chorion TGase is a Ca2+-dependent SH-enzyme similar to the well-characterized TGases of various animals. The highest activity was observed at pH 6.0. The amines examined in the present study inhibited the TGase activity of the purified enzyme. However, they did not necessarily cause effective inhibition of its activity. These properties of the chorion TGase were essentially consistent with our previous observations on polymerization of chorion proteins, resulting in chorion hardening. We compared the amino acid composition of the purified TGase with those of the previously characterized TGases of fishes, such as chum salmon and red sea bream. The results suggest that the chorion 76 kDa TGase is not homologous with those liver TGases in terms of amino acid composition. 相似文献
6.
HJ Lee HK Ha MH Kim YK Jeong PN Kim MG Lee JS Kim DJ Suh SG Lee YI Min YH Auh 《Canadian Metallurgical Quarterly》1997,169(2):517-520
OBJECTIVE: The purpose of this study was to evaluate ERCP and CT findings of ectopic drainage of the common bile duct into the duodenal bulb. CONCLUSION: Although rare, the diagnosis of ectopic drainage of the common bile duct into the duodenal bulb is important to prevent inadvertent damage during biliary tract or gastric surgery and to clarify the cause of chronic peptic ulcers. 相似文献
7.
The crystal structure of Escherichia coli ornithine transcarbamoylase (OTCase, EC 2.1.3.3) complexed with the bisubstrate analog N-(phosphonacetyl)-L-ornithine (PALO) has been determined at 2.8-A resolution. This research on the structure of a transcarbamoylase catalytic trimer with a substrate analog bound provides new insights into the linkages between substrate binding, protein-protein interactions, and conformational change. The structure was solved by molecular replacement with the Pseudomonas aeruginosa catabolic OTCase catalytic trimer (Villeret, V., Tricot, C., Stalon, V. & Dideberg, O. (1995) Proc. Natl. Acad. Sci. USA 92, 10762-10766; Protein Data Bank reference pdb 1otc) as the model and refined to a crystallographic R value of 21.3%. Each polypeptide chain folds into two domains, a carbamoyl phosphate binding domain and an L-ornithine binding domain. The bound inhibitor interacts with the side chains and/or backbone atoms of Lys-53, Ser-55, Thr-56, Arg-57, Thr-58, Arg-106, His-133, Asn-167, Asp-231, Met-236, Leu-274, Arg-319 as well as Gln-82 and Lys-86 from an adjacent chain. Comparison with the unligated P. aeruginosa catabolic OTCase structure indicates that binding of the substrate analog results in closure of the two domains of each chain. As in E. coli aspartate transcarbamoylase, the 240s loop undergoes the largest conformational change upon substrate binding. The clinical implications for human OTCase deficiency are discussed. 相似文献
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Corrosion rates were measured at the exposed spots of rebars near three corners of Muddy Creek Bridge located in northern West Virginia using a 3LP device. Also, chloride contents of the concrete samples taken from the vicinity of the spots were analyzed using a wet chemical method that had been developed in this study. The average corrosion rate over the three spots was 4.66 mA/m2, which is in the range of corrosion damage possible in 10–15 years. The average chloride content of the concrete over the three spots was 703 parts per million (ppm), which is well above the threshold limit value of 260 ppm. Although the corrosion rate measurement method using a 3LP device is by manual operation, it is found to be reliable and effective, and, thus, recommended for future studies of this kind of research. The wet chemical method developed in this study is found to be effective. 相似文献