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排序方式: 共有190条查询结果,搜索用时 15 毫秒
1.
Many optimization problems in science and engineering are highly nonlinear and thus require sophisticated optimization techniques to solve. Traditional techniques such as gradient-based algorithms are mostly local search methods and often struggle to cope with such challenging optimization problems. Recent trends tend to use nature-inspired optimization algorithms. The standard cuckoo search (CS) is an optimization algorithm based on a single cuckoo species and a single host species. This work extends the standard CS by using the successful features of the cuckoo-host co-evolution with multiple interacting species. The proposed multi-species cuckoo search (MSCS) intends to mimic the co-evolution among multiple cuckoo species that compete for the survival of the fittest. The solution vectors are encoded as position vectors. The proposed algorithm is then validated by 15 benchmark functions as well as five nonlinear, multimodal case studies in practical applications. Simulation results suggest that the proposed algorithm can be effective for finding optimal solutions and all optimal solutions are achievable in the tested cases. The results for the test benchmarks are also compared with those obtained by other methods such as the standard cuckoo search and genetic algorithm. The comparison has demonstrated the efficiency of the present algorithm. Based on numerical experiments and case studies, we can conclude that the proposed algorithm can be more efficient in most cases. Therefore, the proposed approach can be a very effective tool for solving nonlinear global optimization problems. 相似文献
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Sudarshan Kumar Vijay M.D. D.M. Bhuwan Chandra Tiwari M.D. D.M. Mukul Misra M.D. D.M. Sudhanshu Kumar Dwivedi M.D. D.M. 《Echocardiography (Mount Kisco, N.Y.)》2014,31(1):E24-E26
The mitral valve aneurysm is a rare complication of infective endocarditis involving mitral or aortic valve. The perforation of the mitral valve aneurysm can lead to significant mitral regurgitation (MR) or thromboembolism, which can cause sudden hemodynamic deterioration. We describe here a case of healed infective endocarditis of the aortic valve with ruptured mitral valve aneurysm that led to severe MR. The aneurysm of the anterior mitral leaflet was diagnosed by two‐dimensional transthoracic echocardiography. In this case, three‐dimensional transthoracic echocardiography demonstrated the detailed morphology of mitral valve aneurysm which resulted in successful surgical repair of the aneurysm. 相似文献
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Baulch Janet E. Acharya Munjal M. Agrawal Sudhanshu Apodaca Lauren A. Monteiro Clarice Agrawal Anshu 《Journal of neuroimmune pharmacology》2020,15(4):852-862
Journal of Neuroimmune Pharmacology - This study examines the link between peripheral immune changes in perpetuation of the Alzheimer’s disease (AD) neuropathology and cognitive deficits. Our... 相似文献
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Sudarshan Kumar Vijay Sudhanshu Kumar Dwivedi Sharad Chandra Ram Kirti Saran 《Indian heart journal》2014,66(5):555-556
Pacing lead dislodgement contributes substantially, to the list of causes of early pacemaker failure.Reel''s syndrome is a rare cause of pacemaker failure, resulting from the dislodging of pacing electrodes by manipulation of the pulse generator by the patient. We describe here an intriguing case of pacemaker lead dislodgement by a novel and frequently underdiagnosed mechanism that mimicked the fluoroscopic diagnosis of reel''s syndrome. 相似文献
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Plasmid DNA immunization against Japanese encephalitis virus: immunogenicity of membrane-anchored and secretory envelope protein. 总被引:5,自引:0,他引:5
Rupinderjeet Kaur Geetanjali Sachdeva Sudhanshu Vrati 《The Journal of infectious diseases》2002,185(1):1-12
Plasmid DNA synthesizing membrane-anchored or secretory Japanese encephalitis virus (JEV) envelope (E) protein and premembrane protein was delivered to mice by intramuscular injection or gene gun. Intramuscular plasmid immunization induced anti-E antibody responses similar to those associated with commercial JEV vaccine. The gene gun induced less antibody response. The 2 forms of the E protein induced similar antibody titers when administered by the same delivery mode. Both plasmids generated high titers of JEV-neutralizing antibodies, although the titers were lower than those induced by the vaccine. Intramuscular DNA immunization induced T helper 1 (Th1) immune responses, and the gene gun induced Th2 responses. Compared with secretory E protein, the membrane-anchored protein heavily skewed the immune response toward either Th1 or Th2, depending on the route of immunization. In an intracerebral JEV challenge model, plasmid-immunized mice had approximately 60% protection; this was not affected by the form of the E protein or by immunization route. 相似文献
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Previously, we described a plasmid pMEa, synthesizing the anchored form of Japanese encephalitis virus (JEV) envelope protein that generated virus-neutralizing antibodies in mice upon intra-muscular injection. The immunized mice showed significant protection against lethal JEV challenge. In order to improve the efficacy of plasmid DNA immunization against JEV, methods need to be employed that would enhance neutralizing antibody titers. Plasmid DNA adsorbed to cationic microparticles has recently been shown to significantly improve its immunogenicity. In the present study, we have adsorbed the plasmid pMEa on cationic microparticles and have compared its immunogenicity with the naked plasmid DNA. As seen in ELISA, the microparticle-adsorbed DNA induced higher titers of anti-JEV antibodies when compared to those induced by the naked DNA. No difference, however, was seen in JEV neutralization titers. The microparticle-adsorbed DNA induced a mixed Th1-Th2 kind of immune responses as opposed to Th1 type of immune responses elicited by the naked DNA. 相似文献
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Characterization of immune response in mice to plasmid DNA encoding dog zona pellucida glycoprotein-3 总被引:5,自引:0,他引:5
To investigate the immunogenicity of plasmid DNA encoding dog zona pellucida glycoprotein-3 (dZP3), the cDNA corresponding to dZP3, was cloned in mammalian expression vector VR1020 downstream of tissue plasminogen activator signal sequence under cytomegalovirus promoter (VRdZP3). In vitro transfection of COS-1 mammalian cells with VRdZP3 plasmid DNA led to its cytosolic expression. The expressed dZP3 has an apparent molecular weight of 45kDa as compared to calculated molecular weight of 38.4 kDa, suggesting possible glycosylation. Immunization of male BALB/cJ mice with VRdZP3 plasmid DNA in saline, by electroporation or adsorbed onto gold microcarriers (delivered by gene gun) generated antibody response against Escherichia coli expressed recombinant dZP3 (r-dZP3). Administration of r-dZP3 in saline following immunization with plasmid DNA led to boosting of the antibody response. Although mice immunized with gene gun exhibited highest antibody titres, the differences in the antibody titres seen by the three modes of plasmid DNA delivery were not statistically significant (P>0.05). Interestingly, female mice immunized with VRdZP3 plasmid DNA using gene gun also generated antibodies against r-dZP3. A dominant IgG1 isotype response was observed in mice immunized with VRdZP3 plasmid DNA using gene gun as compared to a mixed IgG1-IgG2a isotype response when delivered in saline or by electroporation. Immunization with VRdZP3 plasmid DNA also generated cell mediated immune response. The antibodies generated by VRdZP3 plasmid DNA recognized dog native zona pellucida. These studies for the first time, demonstrate the feasibility of generating an immune response to ZP3 by DNA vaccine and that the antibodies thus generated recognize native zona pellucida. 相似文献