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Patel Sapna Kumar Dushyant Chaurasiya Nitesh Kumar Tripathi Shweta 《Semiconductors》2019,53(13):1797-1803
Semiconductors - In the present paper, analytical modeling of surface potential and drain current for hetero-dielectric double gate tunnel FET (HDG-TFET) has been done. The two dimensional (2D)... 相似文献
3.
Journal of Mechanical Science and Technology - An experimental study is performed to explore the effect of swirl and number of swirler vanes on combustion characteristics of methane inverse... 相似文献
4.
Parsania P. H. Sankhavara Dharmesh B. Chopda Jalpa Patel Jignesh P. 《Polymer Bulletin》2020,77(6):3111-3128
Polymer Bulletin - Jute and glass composites of epoxy resin of (2E, 6E)-bis(4-hydroxybenzylidene)cyclohexanone (EBHBC) were prepared by compressing molding technique using three different hardeners... 相似文献
5.
全流程低功耗设计技术的应用 总被引:1,自引:0,他引:1
SameerPatel 《电子设计应用》2004,(1):91-92
随着便携式电子设备的日益使用,要求集成电路IC及SoC的功耗越来越低。在今后日益复杂的设计中,实现一个可靠的电源网络以减小功耗变成了主要的挑战。对于使用者来说,期待每一代新产品都具有新型功能,同时也希望产品的体积小并具有较长的工作时间。解决这个难题的方法之一就是采用新型的IC设计技术,以提供小而且高效的晶体管。在整个设计流程中,为了使器件的性能和可靠性最优,电源方面的限制非常关键。例如在逻辑门应用中,由于开关从一种状态转换到另一种状态从而引起动态功耗。在开关的转换过程中,和晶体管门极相连的所有内部电容将会被… 相似文献
6.
DJ Patterson 《Canadian Metallurgical Quarterly》1994,23(2):313-325
Postgastrectomy syndromes are uncommon but, unfortunately, frustrating for both patient and physician, because treatment with prokinetic agents is often of limited benefit. This article examines the evidence for efficacy of available prokinetic drugs in the management of these difficult disorders. 相似文献
7.
S Moss B Ibbotson H Prosser D Goldberg P Patel N Simpson 《Canadian Metallurgical Quarterly》1997,32(6):344-354
The Psychiatric Assessment Schedule for Adults with Developmental Disability (PAS-ADD) is a semi-structured interview for use with respondents who have learning disability and for key informants. This report investigates the ability of the instrument to detect symptoms that had been found to exist during routine clinical assessment of the patients. Field trials involved 95 referred patients with learning disability and a key informant for each sample member. Clinical opinions of the referring psychiatrists were sought using a symptom checklist. Referrer checklist symptoms and PAS-ADD data were both factor analysed. Validity testing involved (a) computation of correlations between PAS-ADD factors and checklist data and (b) comparison of PAS-ADD and referrers' diagnoses. Results indicated good validity for the PAS-ADD in relation to psychotic symptoms and depressive symptoms. Anxiety symptom identification was not well validated, probably due to small numbers. Expansive mood identified by the referrers was not detected by the PAS-ADD because there is currently no corresponding section in the interview. Where the PAS-ADD produced a diagnosis (in 58 members of the sample), 44 were in agreement with the referrer. Probability of diagnosis by PAS-ADD increased with the number of relevant active symptoms identified by the referrer. The PAS-ADD has been shown in a previous report to have the sensitivity to detect mental disorders not known to psychiatric services. For psychotic and depressive conditions, our results showed that symptom detection was in good agreement with the information provided by the referring psychiatrists on their patients. The PAS-ADD needs a section on hypomania and further investigation of its detection of anxiety disorders. 相似文献
8.
A device that harnesses the mechanical energy of skeletal muscle contracting in a linear configuration has been implanted in goats. This energy convertor transforms muscle work to hydraulic energy that could drive a variety of cardiac assist devices. The device is mounted with a rib clamp and plate affixed to the sternum by cortical bone screws. A transcutaneous hydraulic line carries a silicon based working fluid to an external system that controls the muscle load. In 60 to 70 kg goats, the latissimus dorsi insertion was reattached to the energy convertor. A Telectronics myostimulator with intramuscular electrodes stimulated the latissimus dorsi. In acute implants, hydraulic pressures in excess of 150 psi were obtained. Chronic implantation of the device allowed system evaluation in the conscious unanesthetized animal. Two weeks after implant, hydraulic pressures in excess of 200 psi were obtained and energy transferred to the external loading system exceeded 1 J per contraction. Six weeks after implant, the device continued to cycle freely. These initial results are very promising and suggest an implantable energy convertor is feasible. Development of an energy convertor is an important step toward tether-free skeletal muscle powered cardiac assist devices. 相似文献
9.
Two Caribbean hair sheep breeds, the St. Croix (SC) and Barbados Blackbelly (BB), are found in the United States, and the SC has led to the development of the Katahdin (K), a synthetic breed of hair sheep. These breeds have mature ewe BW ranging from 32 to 54 kg (for BB and SC) and from 55 to 73 kg (K). Hair sheep and hair sheep crosses have lower rectal temperatures and respiration rates than wool breeds and a lower DMI and water intake. There are indications of increased resistance to internal parasites in hair sheep. Although hair sheep are seasonal breeders under U.S. photoperiodic conditions, they tend to perform better under accelerated lambing systems than traditional wool breeds. Fertility, prolificacy, and lamb survival is high in BB and SC, but hair x wool crossbred ewes tend to have a higher level of fertility than hair and wool parent breeds. Ewe productivity is also higher in hair x wool crosses than in wool crosses, particularly when adjusted for ewe BW or under accelerated lambing systems. Hair sheep have a lower ADG and intake of high-energy diets, as well as a lower gain/feed ratio, than wool breeds. Growth rates tend to be higher in SC than in BB. Differences in carcass characteristics are inconsistent between hair and wool breeds. Production characteristics of hair sheep, particularly hair x wool crosses, make them suitable for low-input, sustainable production systems that do not require high growth rates and large carcasses. There is a need to preserve the existing U.S. hair sheep germplasm base in support of such systems. 相似文献
10.
N Delanty MP Reilly D Pratico JA Lawson JF McCarthy AE Wood ST Ohnishi DJ Fitzgerald GA FitzGerald 《Canadian Metallurgical Quarterly》1997,95(11):2492-2499
BACKGROUND: Myocardial reperfusion is believed to be associated with free radical injury. However, indexes of oxidative stress in vivo have been limited by their poor specificity and sensitivity. Isoprostanes are stable products of arachidonic acid formed in a nonenzymatic, free radical-catalyzed manner. We have developed a sensitive and specific assay for one of these compounds, 8-epi prostaglandin (PG) F2 alpha. METHODS AND RESULTS: To address its utility as an index of oxidative stress during coronary reperfusion, we measured urinary levels by gas chromatography/mass spectrometry in a canine model of coronary thrombolysis, in patients with acute myocardial infarction treated with thrombolytic therapy, and in patients after elective coronary artery bypass surgery. Urinary 8-epi PGF2 alpha was unchanged after circumflex artery occlusion in a canine model of coronary thrombolysis (n = 13; 437.2 +/- 56.4 versus 432.7 +/- 55.2 pmol/mmol creatinine) but increased significantly (P < .05) immediately after reperfusion (553.8 +/- 64.7 pmol/mmol). Urinary levels were increased (P < .001) in patients (n = 12) with acute myocardial infarction given lytic therapy (265.8 +/- 40.8 pmol/mmol) compared with age-matched control subjects (n = 20; 91.5 +/- 11.8 pmol/mmol) and patients with stable coronary disease (n = 20; 95.7 +/- 6.3 pmol/mmol). Preoperative levels rose from 113.2 +/- 11.8 to 248.2 +/- 86.3 pmol/mmol at 30 minutes into revascularization to 332.2 +/- 82.6 pmol/mmol by 15 minutes after global myocardial reperfusion (P < .05) and dropped to 181.2 +/- 50.4 pmol/mmol at 30 minutes and 120.2 +/- 9.9 pmol/mmol at 24 hours after bypass surgery (n = 5). Corresponding changes in spin adduct formation, found with electron paramagnetic resonance, were noted in 2 patients. CONCLUSIONS: These data support the hypothesis that free radical generation occurs during myocardial reperfusion. Measurement of isoprostane production may serve as a noninvasive index of oxidative stress. 相似文献