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排序方式: 共有4631条查询结果,搜索用时 15 毫秒
1.
Zenan Yu Julian Moore Jean Calderon Lei Zhai Jayan Thomas 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(39):5289-5295
Cable‐shaped supercapacitors (SCs) have recently aroused significant attention due to their attractive properties such as small size, lightweight, and bendability. Current cable‐shaped SCs have symmetric device configuration. However, if an asymmetric design is used in cable‐shaped supercapacitors, they would become more attractive due to broader cell operation voltages, which results in higher energy densities. Here, a novel coil‐type asymmetric supercapacitor electrical cable (CASEC) is reported with enhanced cell operation voltage and extraordinary mechanical‐electrochemical stability. The CASECs show excellent charge–discharge profiles, extraordinary rate capability (95.4%), high energy density (0.85 mWh cm−3), remarkable flexibility and bendability, and superior bending cycle stability (≈93.0% after 4000 cycles at different bending states). In addition, the CASECs not only exhibit the capability to store energy but also to transmit electricity simultaneously and independently. The integrated electrical conduction and storage capability of CASECS offer many potential applications in solar energy storage and electronic gadgets. 相似文献
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NC Moore 《Canadian Metallurgical Quarterly》1997,86(2):81-82
The nation's health care system is undergoing a period of rapid change that will profoundly affect women's health care services and, ultimately, women's health. Although managed care is quickly becoming the predominant mode of health care delivery in the United States, a new, more consumer-focused, and accountable model known as organized systems of care (OSC) is emerging. OSC development has been driven by large private and public employers seeking to purchase the highest quality health care for the best price. The changes in health care delivery encouraged by these innovative employers will provide women with optimal care and attention, which will in turn help them attract and retain a competitive and productive workforce. 相似文献
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OBJECTIVE: The aims were to validate the use of a direct reading NO electrode, to compare the effects of diverse acting drugs on altering coronary flow (CF) and NO release, and to examine the effects of altered perfusion pressure on flow-induced changes in NO concentration [NO] in the hemoglobin free effluent of guinea pig isolated hearts. METHODS: Hearts were isolated and perfused initially at a constant perfusion pressure (55 mmHg) with a modified Krebs-Ringer's solution equilibrated with 97% O2 and 3% CO2 at 37 degrees C. Heart rate, left ventricular pressure, CF, and effluent pH, pCO2, pO2, and NO generated current were monitored continuously on-line. Effluent was sampled for L-citrulline. Percent O2 extraction and O2 consumption were calculated. [NO] was quantitated with a sensitive amperometric sensor (sensitivity > or = 1 nmol/l approximately 3 pA) and a selective gas permeable membrane. RESULTS: The electrode was not sensitive to changes in solution pO2, flow, or pressure. The electrode was sensitive to pCO2 (-0.50 nmol/l/mmHg) and temperature (+24.5 nmol/l/degree C), so coronary effluent pCO2 was measured to compensate for a small decrease in pCO2 that occurred with an increase in coronary flow, and effluent temperature was rigidly controlled. Serotonin, bradykinin, and nitroprusside increased NO release along with CF, whereas nifedipine, butanedione monoxime, zaprinast, and bimakalim comparably increased CF but did not increase [NO] or NO release. Increases in CF (ml/g/min) and NO release (pmol/g/min), respectively, were 5.0 +/- 1 and 100 +/- 17 for 1 mumol/l serotonin, 7.5 +/- 1 and 148 +/- 18 for 100 nmol/l bradykinin, and 7.8 +/- 1 and 173 +/- 28 for 100 mumol/l nitroprusside. The increases in effluent NO by bradykinin were proportional to the increases in L-citrulline. Tetraethylammonium decreased CF, but did not change NO release, indomethacin changed neither CF nor NO release, and NG-nitro-L-arginine methyl ester (L-NAME) reduced CF by 2.6 +/- 1 ml/g/min and NO release by 25 +/- 8 pmol/g/min. An increase of CF of 8.0 +/- 0.3 ml/g/min, produced by increasing perfusion pressure from 25 to 90 mmHg, increased [NO] by 30 +/- 4 nmol/l; L-NAME but did not reduce the pressure-induced increase in CF, but reduced the increase in [NO] to 10 +/- 5 nmol/l. CONCLUSIONS: This study demonstrates in intact hearts real-time release of NO by several vasodilator drugs and by pressure-induced increases in flow (shear stress) and attenuation of these effects by L-NAME. 相似文献
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WR Volger RS Weiner JO Moore GA Omura AA Bartolucci M Stagg 《Canadian Metallurgical Quarterly》1995,9(9):1456-1460
A phase III clinical trial was designed to determine if more intensive induction and consolidation therapy for acute myeloblastic leukemia increases the remission rate and prolongs survival. A minor objective was to determine if the use of non-cross resistant drugs was more effective than the same drugs used for induction. Patients with untreated leukemia between the ages of 15 and 50 were given daunorubicin 45 mg/m2 for the first 3 days of a 10-day continuous infusion of cytosine arabinoside, initially at a dose of 2000 mg/m2 but reduced to 100 mg/m2 because of toxicity. Those under 36 achieving a complete remission and with an histocompatible donor were assigned to a transplant arm. The rest were randomized to receive one of three consolidation arms: A, cytosine arabinoside, 200 mg/m2 daily for 7 days and daunorubicin 45 mg/m2 daily for 3 days for three courses; B, one course as in Arm A followed by amsacrine, 120 mg/m2 daily for 5 days followed by a 5-day continuous infusion of azacytidine, 150 mg/m2/day; C, thioguanine and cytosine arabinoside, 100 mg/m2 every 12 h and daunorubicin 10 mg/m2 daily for 5 days for three courses followed by four maintenance courses of cytosine arabinoside, 100 mg/m2 daily for 5 days and daunorubicin, 45 mg/m2 for 2 days every 13 weeks. From 1981 to 1986, 398 eligible patients were enrolled and 219 achieved a complete remission. The initial induction dose of cytosine arabinoside was reduced after five of 29 patients exhibited fatal gastrointestinal toxicity. Only 11 patients were assigned to the transplant arm. There were no significant differences in the consolidation arms. The 5 year disease-free survivals were 38, 31 and 27% in arms A, B, and C respectively. Intensive consolidation therapy with the same or different drugs used in induction was as effective as lower dose consolidation followed by maintenance therapy. 相似文献
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A real-time neural system for color constancy 总被引:11,自引:0,他引:11
A neural network approach to the problem of color constancy is presented. Various algorithms based on Land's retinex theory are discussed with respect to neurobiological parallels, computational efficiency, and suitability for VLSI implementation. The efficiency of one algorithm is improved by the application of resistive grids and is tested in computer simulations; the simulations make clear the strengths and weaknesses of the algorithm. A novel extension to the algorithm is developed to address its weaknesses. An electronic system that is based on the original algorithm and that operates at video rates was built using subthreshold analog CMOS VLSI resistive grids. The system displays color constancy abilities and qualitatively mimics aspects of human color perception. 相似文献