932 research outputs found

    Composite Dipolar Recoupling: Anisotropy Compensated Coherence Transfer in Solid-State NMR

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    The efficiency of dipole-dipole coupling driven coherence transfer experiments in solid-state NMR spectroscopy of powder samples is limited by dispersion of the orientation of the internuclear vectors relative to the external magnetic field. Here we introduce general design principles and resulting pulse sequences that approach full polarization transfer efficiency for all crystallite orientations in a powder in magic-angle-spinning experiments. The methods compensate for the defocusing of coherence due to orientation dependent dipolar coupling interactions and inhomogeneous radio-frequency fields. The compensation scheme is very simple to implement as a scaffold (comb) of compensating pulses in which the pulse sequence to be improved may be inserted. The degree of compensation can be adjusted and should be balanced as a compromise between efficiency and length of the overall pulse sequence. We show by numerical and experimental data that the presented compensation protocol significantly improves the efficiency of known dipolar recoupling solid-state NMR experiment

    EVALUATING THE RESEARCH FUNDING OPPORTUNITIES FOR LIBRARY & INFORMATION SCIENCE PROFESSIONALS: AN EVALUATIVE STUDY

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    This research paper highlights the top twenty research funding agencies of the world in the discipline of Information Science and Library Information Science. The citation analysis method has been adopted for the present study and used the database Web of Science and InCites. The aim of this research paper is to make aware research scholars, faculty members, LIS professional and Practitioners, and policymakers about the various National and International top-level funding agencies available to fund their research proposals. The research and academic fraternity and particularly the library professionals who always face problems to get funds to work on any project will able to start new research with innovative ideas with the help of research grant. The finding of the study gives the insight of top-level research funding data with publication ratio of funded research publications in both Open and Closed access journals covered by WoS and InCites bibliographic Database. This paper also focused on the collaboration pattern of funded research publications

    कोमन कार्प (सिप्रनस काप्रियो ) मछलियों में प्रजनन तथा अधिक बीज उत्पादन

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    अलवण जल कोमन कार्प के प्रजनन तकनीक ; प्रजनकों का चयन आदि पर विवरण दिया गया ह

    हरियाणा में मत्स्य पालन की प्रगति वा संभावनायें

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    कृपया पूरा लेख पढे

    Multiple-spin coherence transfer in linear Ising spin chains and beyond: numerically-optimized pulses and experiments

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    We study multiple-spin coherence transfers in linear Ising spin chains with nearest neighbor couplings. These constitute a model for efficient information transfers in future quantum computing devices and for many multi-dimensional experiments for the assignment of complex spectra in nuclear magnetic resonance spectroscopy. We complement prior analytic techniques for multiple-spin coherence transfers with a systematic numerical study where we obtain strong evidence that a certain analytically-motivated family of restricted controls is sufficient for time-optimality. In the case of a linear three-spin system, additional evidence suggests that prior analytic pulse sequences using this family of restricted controls are time-optimal even for arbitrary local controls. In addition, we compare the pulse sequences for linear Ising spin chains to pulse sequences for more realistic spin systems with additional long-range couplings between non-adjacent spins. We experimentally implement the derived pulse sequences in three and four spin systems and demonstrate that they are applicable in realistic settings under relaxation and experimental imperfections-in particular-by deriving broadband pulse sequences which are robust with respect to frequency offsets.Comment: 11 page

    Sight Distance Standards Based On Observational Data Risk Evaluation Of Passing

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    The paper presents an application of a reliability analysis for evaluating the risk associated with passing sight distance (PSD) standards in terms of the expected probability of noncompliance. Calculation of PSD is required to determine where drivers can safely execute passing maneuvers. Traditional PSD standards are based on deterministic, theoretical models, which are calibrated with conservative percentile values for uncertain design inputs to account for uncertainty. The PSD standards do not provide information about the risk of deviation from them. Reliability analysis is a technique that is based on limit state design and that accounts for the propagation of variability from input random parameters to the design outputs. A total of 1,098 passing maneuvers were observed on several two-lane highways in Spain; two data collection methodologies were used: external observations and an instrumented vehicle. The most significant factors affecting PSD were impeding-vehicle speed, passing-vehicle acceleration, and head-ways between impeding and passing vehicles. A uniform acceleration model described the passing-vehicle trajectory. The characterized input parameters and the passing model were used to perform a reliability analysis. The results showed the probability of noncompliance in different scenarios, defined as the proportion of cases in which the required PSD would exceed the available sight distance. American and Spanish PSD standards were evaluated. Geometric design standards presented a probability of noncompliance of about 0.15, whereas some marking standards had a probability of noncompliance exceeding 0.85. These standards may be associated with higher risk levels if they are followed by drivers. As well, PSD risk levels were not consistent for different design speeds, since they underestimated operating speed at some locationsThis paper was developed as a result of a mobility study at the University of British Columbia funded by the Erasmus Mundus Program of the European Commission under the Transatlantic Partnership for Excellence in Engineering project. The authors thank the Spanish Ministry of Economy and Competitiveness, which subsidized the research project, and the Spanish Directorate General of Traffic, Spanish Ministry of Public Works, Valencia Regional Department of Transport, and Valencia province road department for their collaboration during the field study.Llorca Garcia, C.; Moreno Chou, AT.; Sayed, T.; García García, A. (2014). Sight Distance Standards Based On Observational Data Risk Evaluation Of Passing. Transportation research record. 2404:18-26. doi:10.3141/2404-03S18262404Ismail, K., & Sayed, T. (2009). Risk-based framework for accommodating uncertainty in highway geometric design. Canadian Journal of Civil Engineering, 36(5), 743-753. doi:10.1139/l08-146Ismail, K., & Sayed, T. (2010). Risk-Based Highway Design. Transportation Research Record: Journal of the Transportation Research Board, 2195(1), 3-13. doi:10.3141/2195-01Richl, L., & Sayed, T. (2006). Evaluating the Safety Risk of Narrow Medians Using Reliability Analysis. Journal of Transportation Engineering, 132(5), 366-375. doi:10.1061/(asce)0733-947x(2006)132:5(366)Harwood, D. W., Gilmore, D. K., & Richard, K. R. (2010). Criteria for Passing Sight Distance for Roadway Design and Marking. Transportation Research Record: Journal of the Transportation Research Board, 2195(1), 36-46. doi:10.3141/2195-05Wang, Y., & Cartmell, M. P. (1998). New Model for Passing Sight Distance on Two-Lane Highways. Journal of Transportation Engineering, 124(6), 536-545. doi:10.1061/(asce)0733-947x(1998)124:6(536)Polus, A., Livneh, M., & Frischer, B. (2000). Evaluation of the Passing Process on Two-Lane Rural Highways. Transportation Research Record: Journal of the Transportation Research Board, 1701(1), 53-60. doi:10.3141/1701-07Llorca, C., & García, A. (2011). Evaluation of Passing Process on Two-Lane Rural Highways in Spain with New Methodology Based on Video Data. Transportation Research Record: Journal of the Transportation Research Board, 2262(1), 42-51. doi:10.3141/2262-05Carlson, P., Miles, J., & Johnson, P. (2006). Daytime High-Speed Passing Maneuvers Observed on Rural Two-Lane, Two-Way Highway: Findings and Implications. Transportation Research Record: Journal of the Transportation Research Board, 1961, 9-15. doi:10.3141/1961-02Llorca, C., Moreno, A. T., García, A., & Pérez-Zuriaga, A. M. (2013). Daytime and Nighttime Passing Maneuvers on a Two-Lane Rural Road in Spain. Transportation Research Record: Journal of the Transportation Research Board, 2358(1), 3-11. doi:10.3141/2358-01Easa, S. M. (1993). Reliability‐Based Design of Intergreen Interval at Traffic Signals. Journal of Transportation Engineering, 119(2), 255-271. doi:10.1061/(asce)0733-947x(1993)119:2(255)Selvanathan, E. A., & Selvanathan, S. (1994). The demand for transport and communication in the United Kingdom and Australia. Transportation Research Part B: Methodological, 28(1), 1-9. doi:10.1016/0191-2615(94)90027-2Easa, S. M. (2000). Reliability Approach to Intersection Sight Distance Design. Transportation Research Record: Journal of the Transportation Research Board, 1701(1), 42-52. doi:10.3141/1701-06Ibrahim, S. E.-B., & Sayed, T. (2011). Developing safety performance functions incorporating reliability-based risk measures. Accident Analysis & Prevention, 43(6), 2153-2159. doi:10.1016/j.aap.2011.06.006Khoury, J. E., & Hobeika, A. G. (2007). Assessing the Risk in the Design of Passing Sight Distances. Journal of Transportation Engineering, 133(6), 370-377. doi:10.1061/(asce)0733-947x(2007)133:6(370)Khoury, J. E., & Hobeika, A. G. (2012). Integrated Stochastic Approach for Risk and Service Estimation: Passing Sight Distance Application. Journal of Transportation Engineering, 138(5), 571-579. doi:10.1061/(asce)te.1943-5436.0000366Kim, S., & Choi, J. (2013). Effects of preceding geometric conditions on operating speed consistency of multilane highways. Canadian Journal of Civil Engineering, 40(6), 528-536. doi:10.1139/cjce-2012-005

    Role of LIS Professionals to provide authentic information sources during COVID-19 a Pandemic crisis

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    During the national crisis, caused by a novel pandemic such as COVID-19 virus infections, people need authentic information to face such a virus. Libraries need to come forward in such a situation as primary sources of trustworthy information by providing rapid and easy access to those seeking authentic information sources. In this crisis, giving Remote Access, Virtual Library, e-resources, Ask the Librarian reference services to the user in real-time and at scale for a range of scientific- and policy-related responses can be very significant to the academic and research community. The present study has collected data from authentic information sources, mainly Government official portals of Indian states such as the MyGov COVID-19, UTs, and National/International agencies, etc. After analyzing and studying the data, the authentic information sources served to the research community are listed out. This paper also highlights the ratio of COVID-19 publications and highly cited publication of the same, using the Scopus abstracting databases. This study is an original research work focused on the roles and responsibilities and actions taken by the Library and librarians in crisis situations. Hence this study will help Librarians, Information Providers, Practitioners, Policy Makers, Researchers, and development activity in this field

    Astrophysical S_{17}(0) factor from a measurement of d(7Be,8B)n reaction at E_{c.m.} = 4.5 MeV

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    Angular distribution measurements of 2^2H(7^7Be,7^7Be)2^2H and 2^2H(7^7Be,8^8B)nn reactions at Ec.m.E_{c.m.}\sim~4.5 MeV were performed to extract the astrophysical S17(0)S_{17}(0) factor using the asymptotic normalization coefficient (ANC) method. For this purpose a pure, low emittance 7^7Be beam was separated from the primary 7^7Li beam by a recoil mass spectrometer operated in a novel mode. A beam stopper at 0^{\circ} allowed the use of a higher 7^7Be beam intensity. Measurement of the elastic scattering in the entrance channel using kinematic coincidence, facilitated the determination of the optical model parameters needed for the analysis of the transfer data. The present measurement significantly reduces errors in the extracted 7^7Be(p,γ\gamma) cross section using the ANC method. We get S17S_{17}~(0)~=~20.7~±\pm~2.4 eV~b.Comment: 15 pages including 3 eps figures, one figure removed and discussions updated. Version to appear in Physical Review

    COMPARISION OF LOCAL ANAESTHETIC POTENTIALS OF DRUGS HAVING MEMBRANE STABILIZING EFFECT ON INFILTRATION ANAESTHESIA IN GUINEA PIGS

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    Objective : To compare the local anaesthetic action of central neuron sodium channel blockers Phenytoin Sodium, Sodium Valproate and Carbamazepine with peripheral neuron sodium channel blockers Lignocaine using Infiltration anaesthesia in guinea pigs Material and Methods: In the present study,the local anaesthetic effect of Lignocaine with concentration of 0.2%, 0.1% ,0.05% was compared with Phenytoin Sodium, Sodium Valproate and Carbamazepine in concentrations of 0.2%, 0.1% ,0.05% using different dilutions of  0.05N,0.1N,0.2N HCL  in guinea pig by pricking on the skin produces a squeak or  movement  indicating pain is produced. Results : The results of our present study suggest onset of local anaesthesia with lignocaine 0.2% is significantly fast when compared with concentration of 0.1%, and 0.05% indicating it has better efficacy  when  using for various   local anaesthetic  procedures. In addition onset of local anaesthesia with Phenytoin sodium concentrations of 0.2%, 0.1% ,0.05%  is fast  when compared with Sodium valproate concentrations of 0.2%, 0.1% ,0.05%  and  Carbamazepine concentrations 0.2%, 0.1% ,0.05%. Conclusion: Among antiepileptic drugs with local anaesthesia and  membrane stabilizing activity Phenytoin sodium showed fast on set of action when compared with sodium valproate and Carbamazepine indicating it has better efficacy. Keywords : Local Anaesthetics, Membrane Stabilizing, Infiltration anaesthesia

    Inhibition of transforming growth factor-β restores endothelial thromboresistance in vein grafts

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    BackgroundThrombosis is a major cause of the early failure of vein grafts (VGs) implanted during peripheral and coronary arterial bypass surgeries. Endothelial expression of thrombomodulin (TM), a key constituent of the protein C anticoagulant pathway, is markedly suppressed in VGs after implantation and contributes to local thrombus formation. While stretch-induced paracrine release of transforming growth factor-β (TGF-β) is known to negatively regulate TM expression in heart tissue, its role in regulating TM expression in VGs remains unknown.MethodsChanges in relative mRNA expression of major TGF-β isoforms were measured by quantitative polymerase chain reaction (qPCR) in cultured human saphenous vein smooth muscle cells (HSVSMCs) subjected to cyclic stretch. To determine the effects of paracrine release of TGF-β on endothelial TM mRNA expression, human saphenous vein endothelial cells (HSVECs) were co-cultured with stretched HSVSMCs in the presence of 1D11, a pan-neutralizing TGF-β antibody, or 13C4, an isotype-control antibody. Groups of rabbits were then administered 1D11 or 13C4 and underwent interpositional grafting of jugular vein segments into the carotid circulation. The effect of TGF-β inhibition on TM gene expression was measured by qPCR; protein C activating capacity and local thrombus formation were measured by in situ chromogenic substrate assays; and VG remodeling was assessed by digital morphometry.ResultsCyclic stretch induced TGF-β1 expression in HSVSMCs by 1.9 ± 0.2-fold (P < .001) without significant change in the expressions of TGF-β2 and TGF-β3. Paracrine release of TGF-β1 by stretched HSVSMCs inhibited TM expression in stationary HSVECs placed in co-culture by 57 ± 12% (P = .03), an effect that was abolished in the presence of 1D11. Similarly, TGF-β1 was the predominant isoform induced in rabbit VGs 7 days after implantation (3.5 ± 0.4-fold induction; P < .001). TGF-β1 protein expression localized predominantly to the developing neointima and coincided with marked suppression of endothelial TM expression (16% ± 2% of vein controls; P < .03), a reduction in situ activated protein C (APC)-generating capacity (53% ± 9% of vein controls; P = .001) and increased local thrombus formation (3.7 ± 0.8-fold increase over vein controls; P < .01). External stenting of VGs to limit vessel distension significantly reduced TGF-β1 induction and TM downregulation. Systemic administration of 1D11 also effectively prevented TM downregulation, preserved APC-generating capacity, and reduced local thrombus in rabbit VGs without observable effect on neointima formation and other morphometric parameters 6 weeks after implantation.ConclusionTM downregulation in VGs is mediated by paracrine release of TGF-β1 caused by pressure-induced vessel stretch. Systemic administration of an anti-TGF-β antibody effectively prevented TM downregulation and preserved local thromboresistance without negative effect on VG remodeling.Clinical RelevanceVein grafts (VGs) are commonly used conduits for coronary and peripheral arterial bypass surgeries. Thrombosis is a major cause of early VG failure. Trombomodulin (TM), a key component of the anticoagulant protein C pathway, is downregulated early after VG implantation and facilitates local thrombus formation. We found that paracrine release of transforming growth factor-β1 (TGF-β1), caused by pressure-induced stretch, was a potent negative regulator of TM in rabbit VGs. Administration of a neutralizing anti-TGF-β antibody effectively prevented TM downregulation and reduced local thrombus generation without adversely affecting long-term VG remodeling. This may represent a novel strategy to improve patency in patients undergoing arterial bypass procedures
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