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921.
A method has been presented in recent papers for deriving precisely stabilized waveform generators by relating them to second-order conservative oscillators. The present paper suggests a method for considerably generalizing the previous class ofgenerator models. This should enable the development of a larger variety of waveform generators with ease and flexibility. The new method is analyzed and is shown to possess implications to theoretical biology and other fields. 相似文献
922.
外国直接投资对于中国技术创新作用的影响分析 总被引:11,自引:0,他引:11
本文运用我国29个省、市、自治区从1995到2003年的面板数据定量地评估了外国直接投资对我国技术创新(用专利申请量来表征)作用的影响.结论认为:FDI对于中国的技术创新会发挥积极的影响,但前提是要跨越一定的人力资本门槛;FDI对我国外观设计的专利申请量影响程度最大,而对发明专利申请量影响最小,对实用新型的专利申请量影响次之;另外FDI对中国技术创新的影响也存在着明显的区域性特征,FDI对东部地区专利申请量的影响要强于对中部地区的影响,而FDI对于西部地区的专利申请量几乎没有影响. 相似文献
923.
In 1982, the Small Business Innovation Development Act established the small business innovation research (SBIR) program. This program reserves a percentage of federal agencies’ extramural R&D budgets for research projects conducted by small businesses. When this Act was reauthorized in 1992, the selection criteria for funding dramatically increased the likelihood of funding for projects that promised to lead to commercial success. Using data from a survey of the SBIR program award recipients at NASA Langley Research Center, we address three questions about this change: (i) was there a shift to projects with more commercial potential? (ii) did these projects experience higher rates of commercial success? and (iii) was there a reduction in basic research accompanying the increased commercial success? Our analysis suggests, the answer to all three of these questions is ‘yes’. 相似文献
924.
925.
Y. P. Bhandary K. N. Krithika Sandeep Kulkarni M. V. R. Reddy B. C. Harinath 《Indian journal of clinical biochemistry : IJCB》2006,21(1):1-7
Lymphatic filariasis caused mainly by infection fromW. bancrofti andB. malayi remains a major cause of clinical morbidity in tropical and subtropical countries. Analysis ofB. malayi mf, infective larval and adult worm lysates for the activity of enzymes led to the demonstration of activities of three key
enzymes of carbohydrate metabolism viz., Malate dehydrogenase (MDH), Malic enzyme (ME) and Glucose-6-phosphate dehydrogenase
(G6PDH) in all the three stages of the parasite. The specific activity of all the three dehydrogenases was significantly high
in mf lysate compared to their activity in lysates of the other two stages (P<0.001). Analysis by native polyacrylamide gel
to their activity inlysates of the other two stages (P<0.001). Analysis by native polyacrylamide gel electrophoresis (PAGE)
using 7.5% non-gradient gel showed the presence of two isoforms of each of the three enzymes (MDH, ME & G6PDH) in mf lysate,
while only one form of each enzyme was present in L3 larval and adult worm lysates. Further proteolytic enzyme activity was demonstrated both in microfilarial and infective larval
lysates ofB. malayi. While both mf and L3 larval lysates showed optimal protease activity at alkaline pH of 9.0, the mf lysate showed increased activity also at pH
3.0. The infective larval lysate was markedly inhibited by Tosylamide-L-Phenylalanine chloromethyl ketone (TPCK), a thiol
protease inhibitor, while the protease activity in mf lysate was significantly inhibited by both TPCK and a serine protease
inhibitor Phenyl Methyl Sulphonyl Flouride (PMSF). In sodium do-decyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE),
using gelatin copolymerized gel, the microfilarial lysate showed 3 protease molecules of 40 kDa, 180 kDa and 200 kDa and the
L3 larval lysate had 6 protease molecules of 18, 25, 37, 49, 70 and 200 kDa size. 相似文献
926.
Heat transfer in laminar tube flow with convective boundary conditions and axial heat conduction in the fluid is solved exactly. The effects of the external Biot numbers and the axial conduction in fluid on the temperature distribution and the local Nusselt number are determined for both the upstream and the downstream regions. In order to illustrate the effects of velocity profile, the results for the slug flow and the parabolic velocity profiles are plotted simultaneously. The heat transfer characteristics of the flow are found to be rather sensitive to the Péclét number, the external Biot numbers and the velocity profile in the thermal entrance region. 相似文献
927.
R. Alli B. Bhunia G. P. Chhotray M. V. R. Reddy B. C. Harinath 《Indian journal of clinical biochemistry : IJCB》2003,18(1):61-64
Sera samples of 7 microscopic haematuria cases collected before and after treatment with Diethylcarbamazine citrate, (DEC),
9 microfilaraemic cases and 19 endemic normal individuals were analysed for filarial antigen and IgG antibody levels. Filarial
antigen was detected in 5 of the 7 microscopic haematuria cases, of which 3 turned negative for antigen after treatment with
DEC. While none of the 7 haematuria cases were positive for filarial IgG antibodies, before the DEC treatment, all of them
turned positive after DEC treatment. The sensitivity and specificity values(to detect mf +ve cases) were 89% and 90% respectively
for the detection of filarial antigen and 78% and 95% respectively for the detection of filarial IgG antibodies. 相似文献
928.
K. S. Motghare Anil Bhutey B. B. Murrhar Madhur Gupta A. W. Meshram Y. Balsubramanium 《Indian journal of clinical biochemistry : IJCB》2001,16(2):213-215
With the growing interest in the concept of free radicals in the pathogenesis of myocardial ischemia, it was thought worthwhile
to study the changes in lipid peroxides and antioxidant enzyme glutathione peroxidase (GPx) in ischemic heart disease (IHD).
The study was carried out on 76 patients of IHD-38 of acute myocardial infarction (AMI) and 38 of stable ischemic heart disease
(SIDH). They were age and sex matched with 38 normal healthy controls. A significant increase (p<0.001) in lipid peroxides
as malondialdehyde (MDA) (5.9±0.7 mmol/L) and a decrease in GPx (24.6±2.2 U/gmHb) was found in patients of AMI when compared
with controls. There was no significant difference in these values in SIHD. Thus this study confirms the earlier findings
that MDA and GPx are useful parameters in IHD and their magnitude is dependent on severity and/or duration of ischemia. We
suggest that these tests would be of use in smaller institutions with limited facilities. 相似文献
929.
Cataglyphis is an ant of desert regions and has a behavioural pattern comparable with that of the bee, but much easier to study. It has a well-developed system of foraging and navigating and a social organisation well adapted to its environment. This review, by two independent research workers who have devoted much time to field studies, is the first to bring together most of the existing information about these fascinating insects. 相似文献
930.
Two small-gain theorems and a passivity theorem yielding stability results for general feedback systems are shown to be equivalent. 相似文献