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1.
A microprocessor-based system with 32 A/D, 24 D/A, and 16 ac load controllers, has been designed and built to monitor and control an ion beam thin-film deposition system. The A/D and D/A channels have electrical isolation of 7.5 kV between channels and between input and output. The microprocessor system keeps the ion beam deposition parameters stable for extended periods of operation and it is proposed as a means to greatly simplify switching from one deposition species to another to grow thin multilayer or alloy films.  相似文献   
2.
The requirements on an object-oriented DBMS for management of information in a large, complex enterprise are presented. These requirements aid in the achievement of an environment characterized by data sharing, open architectures, application and data portability, and assurance of data integrity. They were defined from the point of view of a user of the DBMS; therefore they describe the expected functionality of the DBMS and do not specify the method of implementation to achieve this functionality. They encompass requirements on the data model, query and data manipulation languages, the system architecure, interfaces to the system, change management, and transaction management.  相似文献   
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本文通过测试测量方案介绍了如何进行医疗设备的精确电池备份。  相似文献   
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We cloned the Saccharomyces kluyveri HIS3 homolog, k-HIS3, and made a partial deletion of the gene. The k-HIS3 gene complemented a HIS3 deletion in S. cerevisiae. The DNA sequences of the open reading frames (ORFs) of the HIS3 homologs are 70% identical at the DNA level and 83% identical at the deduced amino acid level. The ORF upstream of the k-HIS3 gene is related to the PET56 gene of S. cerevisiae found upstream of the HIS3 gene of S. cerevisiae. The ORF downstream from the k-HIS3 gene is not related to the DED1 gene found downstream of the HIS3 gene in S. cerevisiae.  相似文献   
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A method for analyzing the fluorine content of glass using a microwave oven to digest the glass is presented. Analysis time and secondary waste generation are reduced using this method, without sacrificing accuracy.  相似文献   
8.
BACKGROUND: We have previously observed a potentiation of the metabolic response to cachectin/tumor necrosis factor (TNF) by total parenteral nutrition (TPN) but not in anorexic orally fed animals. We hypothesized that nutritional status might affect TNF clearance kinetics. METHODS: We compared the clearance of a bolus of labeled TNF in TPN-fed animals given sufficient nutrients to grow called weight-gaining rats (WGR) with those given 50% of the WGR called weight-losing rats (WLR) and with orally fed rats (OFR). Data were analyzed using a two-compartment open system model and by linear systems analysis. RESULTS: The data from both types of analysis indicator that although metabolic clearance was similar, WGR had a slower fractional TNF clearance rate (FCR) as well as a larger volume of distribution than WLR or OFR. Further analysis showed that an increased proportion of the total mass of TNF resided in a plasma-associated compartment in WGR compared with WLR and OFR. In addition, WGR had reduced uptake of labeled TNF by the kidney. CONCLUSION: The data suggest that nutrition support influences either the distribution of TNF or the FCR, resulting in a greater retention in the plasma-associated compartment with intact absolute removal rates. This study has important implications concerning the type of nutrition support provided to the critically ill patient because our data suggest that clinical states with increased circulating TNF levels may be adversely affected by currently available nutritional practices.  相似文献   
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Rates of poor psychological adjustment of children with sickle cell disease remained relatively constant over initial and follow-up assessment points. 50 children (aged 7–12 yrs) and their mothers completed the initial protocol. 30 children completed the follow-up plus 5 additional children and their mothers. These Ss were aged 7–24 yrs at follow-up. With initial levels of adjustment controlled, children's strategies for coping with pain accounted for a significant increment in child-reported symptoms and mother-reported internalizing behavior problems at follow-up beyond the contribution of illness and demographic parameters and follow-up interval. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Explored the construct validity of transactional analysis (TA) ego state concepts. Ego states are defined as coherent systems of thoughts, feelings, and behaviors. 65 university students seeking therapy and 95 university students not receiving therapy completed the Adjective Checklist (ACL) and the Brief Symptom Inventory (BSI). Ego state scores from the ACL correlated with BSI psychological distress in predicted directions. Four of the 5 TA ego state scores differentiated Ss seeking therapy from Ss not seeking therapy. Furthermore, ego state scores changed over the course of therapy, indicating a reduction of distress. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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