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Co_(6)Se_(8)(PEt_(3))_(6) superatoms as tunable chemical dopants for two-dimensional semiconductors

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npj Computational Materials 2018年第1期4卷 373-378页

作者： Arthur C.Reber shiv n.Khanna Department of Physics Virginia Commonwealth UniversityRichmondVA 23284USA

Electronic,optoelectronic,and other functionalities of semiconductors are controlled by the nature and density of carriers,and the location of the Fermi *** strategies to tune these parameters holds the key to precise control over semiconductors *** propose that ligand exchange on superatoms can offer a systematic strategy to vary these *** demonstrate this by considering a WSe_(2) surface doped with ligated metal chalcogenide Co_(6)Se_(8)(PEt_(3))_(6) *** superatoms are characterized by valence quantum states that can readily donate multiple *** find that the WSe_(2) support binds more strongly to the Co_(6)Se_(8) cluster than the PEt3 ligand,so ligand exchange between the phosphine ligand and the WSe_(2) support is energetically *** metal chalcogenide superatoms serves as a donor that may transform the WSe_(2) p-type film into an ntype *** theoretical findings complement recent experiments where WSe_(2) films with supported Co_(6)Se_(8)(PEt_(3))_(6) are indeed found to undergo a change in behavior from p-to *** further show that by replacing the PEt3 ligands by CO ligands,one can control the electronic character of the surface and deposited species.

关键词： properties. semiconductors holds

Homology modeling and functional annotation of bubaline pregnancy associated glycoprotein 2

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Journal of Animal Science and Biotechnology 2012年第2期3卷 68-76页

作者： Bhaskar Ganguly shiv Prasad Department of Veterinary Physiology and Biochemistry College of Veterinary and Animal SciencesG.B.Pant University of Agriculture and TechnologyPantnagarPIN:263145India Department of Animal Reproduction Gynecology and ObstetricsCollege of Veterinary and Animal SciencesG.B.Pant University of Agriculture and TechnologyPantnagarPIN:263145India

Background： Pregnancy associated glycoproteins form a diverse family of glycoproteins that are variably expressed at different stages of gestation. They are probably involved in immunosuppression of the dam against the fetomaternal placentome. The presence of the products of binucleate cells in maternal circulation has also been correlated with placentogenesis and placental re-modeling. The exact structure and function of the gene product is unknown due to limitations on obtaining purified pregnancy associated glycoprotein ***： Our study describes an in silico derived 3D model for bubaline pregnancy associated glycoprotein 2. Structure-activity features of the protein were characterized, and functional studies predict bubaline pregnancy associated glycoprotein 2 as an inducible, extra-cellular, non-essential, n-glycosylated, aspartic pro-endopeptidase that is involved in down-regulation of complement pathway and immunity during pregnancy. The protein is also predicted to be involved in nutritional processes, and apoptotic processes underlying fetal morphogenesis and remodeling of feto-maternal ***： The structural and functional annotation of buPAG2 shall allow the designing of mutants and inhibitors for dissection of the exact physiological role of the protein.

关键词： Bubaline Homology modeling Pregnancy associated glycoprotein (PAG) Structure Function

Laser synthesized nanoparticle alloys of metals with bulk miscibility gaps

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Progress in natural Science:Materials International 2018年第4期28卷 456-463页

作者： Kenneth A.Kane Arthur C.Reber shiv n.Khanna Massimo F.Bertino Department of Physics Virginia Commonwealth University

The nanoscale alloying of metals with bulk miscibility gaps, Ag-Pt and Ag-Rh, has been investigated using pulsed laser ablation of solids in solution(PLASiS). The procedure was in two steps. In the first step, the suspensions of monometallic nanoparticles were prepared by ablation of a metal rod submerged in water. In the second step,the monometallic suspensions were mixed and alloying was induced by re-irradiation. For the Ag-Pt system, a surface plasmon resonance was observed in the monometallic silver suspension. The surface plasmon resonance vanished in re-irradiated Ag-Pt suspensions, indicating alloying. Selected Area Electron Diffraction(SAED)analysis showed that the nanoparticles had a fcc structure with a lattice constant intermediate between that of monometallic Ag and Pt nanoparticles. First principles theoretical investigations of the mixing energy of Ag-Pt clusters confirm that mixing is favored at around ～1 nm. The same procedure used for Ag-Pt was followed for Ag-Rh. In this system where the two metals present miscibility gaps even in the liquid phase, no evidence of alloying was observed. Correspondingly, theoretical investigations found that the mixing energy of Ag-Rh clusters did not favor alloying.

关键词： nano alloys Laser ablation Silver-platinum nanoparticles Silver-rhodium nanoparticles

Blue-Shift and Enhanced Photoluminescence in BaMgAl10O17:Eu2+ nanophosphor under VUV Excitation for PDPs Application

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Materials Sciences and Applications 2010年第1期1卷 25-31页

作者： Raghvendra Singh yadav shiv Kumar Pandey Avinash Chandra Pandey 不详

In this report, five systems of varied diameters viz. 62 nm, 85 nm, 115 nm, 160 nm and 450 nm of BaMgAl10O17:Eu2+ nanorods are prepared by solution combustion approach and with annealing at different temperature in reduced atmosphere (n2 + H2). An intense broad blue photoluminescence (PL), corresponding to the electronic transition of Eu2+ from the 4f 6 5d excited state to the 4f 7 ground state, is observed. The blue-shift and enhanced photoluminescence is also observed, and found to be highly dependent on the size of diameter of BaMgAl10O17:Eu2+ nanostructures. The change in decay time and color-coordinates with change in size of diameter of BaMgAl10O17:Eu2+ nanostructure have been analysed and thoroughly discussed.

关键词： Quantum Confinement Effect nanophosphor PDPs

Endoscopic management of acute cholangitis in elderly patients

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World Journal of Gastroenterology 2006年第40期12卷 6551-6555页

作者： naresh Agarwal Barjesh Chander Sharma shiv K Sarin Department of Gastroenterology GB Pant Hospital New Delhi India

AIM: To evaluate clinical presentation, etiology, compli-cations and response to treatment in elderly patients with acute ***: Demographics, etiology of biliary obstruc-tion, clinical features, complications and associated systemic diseases of 175 patients with acute cholangitis were recorded. Endoscopic biliary drainage was performed using nasobiliary drain or stent. The complications related to ERCP, success of biliary drainage, morbidity, mortality and length of hospital stay were evaluated. RESULTS: Of 175 patients, 52 aged ≥ 60 years (groupⅠ, age nd 105 were men. Fever was present in 38 of 52 patients of group Ⅱ compared to 120 of 123 in groupⅠ. High fever (fever ≥ 38.0℃) was more common in groupⅠ(118/120 vs 18/38). Hypotension (5/123 vs 13/52), altered sensorium (3/123 vs 19/52), peritonism (22/123 vs 14/52), renal failure (5/123 vs 14/52) and associated comorbid diseases (4/123 vs 21/52) were more common in group Ⅱ. Biliopancreatic malignancy was a common cause of biliary obstruction in group Ⅱ (n = 34) and benign diseases in groupⅠ(n = 120). Indications for biliary drainage were any one of the following either singly or in combination: a fever of ≥ 38.0℃ (n = 136), hypotension (n = 18), peritonism (n = 36), altered sensorium (n = 22), and failure to improve within 72 h of conservative management (n = 22). High grade fever was more common indication of biliary drainage in groupⅠand hypotension, altered sensorium, peritonism and failure to improve within 72 h of conservative management were more common indications in group Ⅱ. Endoscopic biliary drainage was achieved in 172 patients (nasobiliary drain: 56 groupⅠ, 24 group Ⅱ, stent: 64 groupⅠ, 28 group Ⅱ) without any significant age related difference in the success rate. Abdominalpain, fever, jaundice, hypotension, altered sensorium, peritonism and renal failure improved after median time of 5 d in 120 patients in groupⅠ(2-15 d) compared to 10 d in 47 patien

关键词： Acute cholangitis Endoscopic biliary drainage Endoscopic retrograde cholangio-pancreatography Common bile duct stones Carcinoma gall bladder

Population structure analysis and determination of neurotoxin content in a set of grass pea (Lathyrus sativus L.) accessions of Bangladesh origin

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The Crop Journal 2018年第4期6卷 435-442页

作者： Priyanka Gupta Sripada M. Udupa Debjyoti Sen Gupta Jitendra Kumar shiv Kumar International Center for Agricultural Research in the Dry Areas Rabat Institute Rabat Morocco Department of Plant Sciences North Dakota State University Fargo ND 58105 USA ICAR-Indian Institute of Pulses Research Kanpur Uttar Pradesh 208024 India

Grass pea(Lathyrus sativus L.) is a crop that is considered one of the more resilient to climate change. With protein-rich seeds and leaves, it has strong potential as human food as well as animal feed and fodder. However, genetic improvement in this crop remains stagnant owing to the poor characterization of its genetic resources. In this study, we characterized 118 accessions of grass pea with 18 EST-SSR markers. A total of 118 accessions, 101 of L. sativus(100 cultivated accessions from Bangladesh and one wild accession) and 17 wild accessions of other Lathyrus species, were used. A total of 67 alleles were detected, with an average of 3.72 alleles per locus and average polymorphism information content of 0.52. A dissimilarity matrix was formed and hierarchical cluster analysis performed using the UPGMA method grouped genotypes into four main clusters. Cluster analysis based on the genetic dissimilarity revealed a clear grouping of the 100 cultivated and 18 wild accessions into four main groups. Group I consisted of 20 accessions with high β-n-oxalyl-L-α,β-diaminopropionic acid(β-ODAP) concentration. Of these 20 accessions, 17 were wild accessions. Only one wild accession(L. cicera) was clustered in group II, which contained 35 accessions. Most of the group II accessions contained low β-ODAP. Group III was represented by 34 accessions, many of them with high β-ODAP. Group IV consisted of 29 accessions, a few of which had very high β-ODAP concentrations. Analysis of molecular variance of the microsatellite data showed significantly higher values of molecular variance between(83%) than within(17%) populations. These characterized accessions will be useful in grass pea breeding programs.

关键词： Lathyrus Population structure EST-SSRβ-ODAP Genetic diversity

Phacoemulsification versus small incision cataract surgery in patients with uveitis

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International Journal of Ophthalmology(English edition) 2015年第5期8卷 965-970页

作者： Rahul Bhargava Prachi Kumar shiv Kumar Sharma Manoj Kumar Avinash Kaur Department of Ophthalmology Laser Eye Clinic Department of Pathology Santosh medical College and Hospital Department of Ophthalmology Rotary Eye Hospital

AIMTo compare the safety and efficacy of phacoemulsification and small incision cataract surgery (SICS) in patients with uveitic *** a prospective, randomized multi-centric study, consecutive patients with uveitic cataract were randomized to receive phacoemulsification or manual SICS by either of two surgeons well versed with both the techniques. A minimum inflammation free period of 3mo (defined as less than 5 cells per high power field in anterior chamber) was a pre-requisite for eligibility for surgery. Superior scleral tunnel incisions were used for both techniques. Improvement in visual acuity post-operatively was the primary outcome measure and the rate of post-operative complications and surgical time were secondary outcome measures, respectively. Means of groups were compared using t-tests. One way analysis of variance (AnOVA) was used when there were more than two groups. Chi-square tests were used for proportions. Kaplan Meyer survival analysis was done and means for survival time was estimated at 95% confidence interval (CI). A P value of nsidered statistically *** hundred and twenty-six of 139 patients (90.6%) completed the 6-month follow-up. Seven patients were lost in follow up and another six excluded due to either follow-up less than six months (n=1) or inability implant an intraocular lens (IOL) because of insufficient capsular support following posterior capsule rupture (n=5). There was significant improvement in vision after both the procedures (paired t-test; Pn first postoperative day, uncorrected distance visual acuity (UDVA) was 20/63 or better in 31 (47%) patients in Phaco group and 26 (43.3%) patients in SICS group (P=0.384). The mean surgically induced astigmatism (SIA) was 0.86±0.34 dioptres (D) in the phacoemulsification group and 1.16±0.28 D in SICS group. The difference between the groups was significant (t-test, P=0.002). At 6mo, corrected distance

关键词： small incision cataract surgery phacoemulsification uveitis corrected distance visual acuity uncorrected distance visual acuity

Efficacy of Shanvac-B recombinant DnA hepatitis B vaccine in health care workers of northern India

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Hepatobiliary & Pancreatic Diseases International 2010年第4期9卷 393-397页

作者： Varsha Thakur nirupma T Pati Rajkumar C Gupta shiv K Sarin Department of Gastroenterology GB Pant Hospital

BACKGROUnD: Health care workers (HCWs) constitute a high-risk population of HBV infection. There are limited data on the efficacy of vaccination in HCWs in India. This study was to evaluate the efficacy of indigenous recombinant hepatitis B vaccine, Shanvac-B, in HCWs. METHODS: In 597 HCWs screened before the vaccination, 216 (36.2%) showed the presence of at least one of the markers of HBV/HCV infection. Of the remaining 381 (63.8%) HCWs who were considered for vaccination, only 153 (age 18-45 years; 48 males and 105 females) were available for final assessment. These HCWs received 20 μg of vaccine at 0, 1 and 6 months. They were asked for the reactogenicity and monitored for the seroprotective efficacy of the vaccination. Anti-HBs titres were measured after vaccination at 1, 2 and 7 months. The presence of anti-HBs titers equal to 1 MIU/ml was considered as seroconversion and that of titres greater than 10 MIU/ml as seroprotection. RESULTS: After vaccination, 32 males (67%) and 76 females (72%) showed seroconvertion; finally 12 (25%) of the males and 47 (45%) of the females were seroprotected. Seroprotection at 2 and 7 months was more dominant in the females than in the males (96% vs. 56%, P=0.001, 100% vs. 85%, P=0.0001), respectively. Geometric mean titres of anti-HBs after vaccination were also higher in the females than in the males (257±19.7 vs. 29±1.88 MIU/ml, P=0.01, 1802±35.2 vs. 306±13.6 MIU/ml, P≤0.05, 6465±72 vs. 2142±73.6 MIU/ml, Pn male HCWs showed unsatisfactory response, non-response (n=3, 6%) and hypo-response (≤10 MIU/ml, n=4, 8%) at the end of vaccination. Smoking and alcoholism were significantly correlated with unsatisfactory response. no significant adverse effects of vaccination were observed in any ***: The presence of HBsAg in HCWs indicates that a high proportion of HCWs are infected with HBV and HCV in India. Recombinant indigenous vaccine Shanvac-B is highly efficacious in HCWs, and its immunogenicity is significa

关键词： health care workers hepatitis B virus hepatitis C virus seroprotection immunogenicity Shanvac-B

Emerging Applications of Optical Coherence Tomography Angiography (OCTA) in neurological research

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Eye and Vision 2018年第1期5卷 107-117页

作者： Liang Wang Olwen Murphy natalia Gonzalez Caldito Peter A.Calabresi shiv Saidha Department of Biology Johns Hopkins UniversityKrieger School of Arts and SciencesBaltimoreMDUSA Division of neuroimmunology and neurological Infections Johns Hopkins Hospital600 N.Wolfe St.BaltimoreMD 21287USA

Purpose:To review the clinical and research value of optical coherence tomography angiography(OCTA)in the field of ***:Current literature involving OCTA were reviewed through PubMed using the search terms“optical coherence tomography angiography”,with“multiple sclerosis”,“Alzheimer’s disease”,“optic neuropathy”,or other closely-related ***:OCTA has been applied in research to advance our understanding of the pathobiology of neurological ***-derived blood flow and vessel density measures are altered in multiple sclerosis(MS),Alzheimer’s disease(AD),and various optic neuropathies(On)in varying regions of the posterior segment vasculature of the *** emerging research findings support the occurrence of retinal vascular alterations across a host of neurological disorders and raise the possibility that vasculopathy can be clinically relevant since it contributes to the pathobiology of several neurological ***:OCTA may be beneficial for neurological *** investigations using OCTA in neurological disorders will help to further validate its clinical and research utilities in terms of characterizing the role of vasculopathy in neurological disorders.

关键词： Optical coherence tomography angiography neurology Multiple sclerosis Alzheimer’s disease Optic neuropathy