334 research outputs found

    C20 cluster-assembled solids and adsorption of C20 on 2D materials

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    C60具有优异的性能,如高温超导电性,因此它的发现激发了对碳团簇广泛的理论和实验研究。C60超导的特性来源于电子-声子耦合,而电声子耦合会随着团簇尺度的减小而增大,因此寻找最小的富勒烯引起了极大的关注。在众多碳团簇中,C20是最小、最简单并且是曲率最大的富勒烯结构。由于C20电声子耦合比C60强,因此可以预测C20是高温超导的更好的潜在材料。因此,本文研究了基于C20的团簇组装结构。另外,自从石墨烯问世以来,相比于其体相对应物而言,二维蜂窝状晶体由于其独特的对称性引起了广泛的兴趣。除了对这些纯二维材料本征性质的研究之外,吸附原子或者分子对这些二维材料带来的效应也得到极大的关注。由石墨烯和其他二...The discovery of fullerene C60 stimulated extensive theoretical and experimental studies of carbon clusters, because of its excellent properties such as high temperature carbon superconductivity. The possibility of superconductivity arising from electron-phonon coupling, and vibronic coupling becomes large as the cluster size decreases. So, tremendous attention has been focused to explore the smal...学位:理学博士院系专业:物理科学与技术学院_凝聚态物理学号:1982013015445

    Effect of Direct Participation on Perceived Organizational Performance: A Case Study of Banking Sector of Pakistan

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    Purpose: The purpose of this study was to find out the association between the HR practices and perceptions of firm performance and to know, understand and investigate the scope of relationship among different types of employee participation (Delegative & Consultative) and organizational performance in banking sector of Pakistan. Methodology: To investigate the relationship that exists between employee participation and firms, performance cross sectional survey design was used for collecting data based on subjective measures. Data was analyzed through MS Excel 2007 & SPSS (17.0), then descriptive, correlations and regression analysis was applied to find out the result for describing empirical and statistical relationship between dependent and independent variables. Findings:  Correlation results shows that the direct participation (Delegative & Consultative) have weak, positive and significant impact on organizational performance. Whereas, regression model results also depicts that employee participation has significant impact on organizational performance. The variation in organizational performance is explained about 23% by the independent variables e.g; delegative & consultative participation which is very minor so, we can conclude that contribution of other HRM variables towards organizational performance is comparatively high. These results are consistent with (Singh, 2004) for the same variable. Research Limitations: The study was limited to only banking sector of Pakistan. This was based on perceived measures that the organizational performance and the forms of direct participation. So the data collected was based on perceptual and subjective measures, generally objective measures are more reliable and consistent to the outcome and results. Practical Implications: Results revealed that direct participation has minor contribution towards organizational performance in Pakistani settings but one could not achieve the desired results by ignoring this key variable. So it is advisable that direct participation must be used in combination of with other HRM variables to boost the performance. Originality/Value: This paper furthers our understanding of the role that employee participation attributes organizational performance. Key Words: Banking Sector, Direct Participation: Delegative & Consultative, HRM Practices, Perceived Organizational Performance, Pakista

    Testing the law of one price in gram markets of Pakistan

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    Regional market integration in many agricultural commodities has been extensively studied for the insight, it provides in to the functioning of such markets; such studies provide valuable information about the dynamics of market adjustment, and whether there exist market imperfection, which may justify government intervention. This study used the monthly wholesale price (Rs. /40 kg) data from January 1991 to December 2006 of gram, in Logarithmic form and empirically estimated the degree of integration in gram markets of Pakistan using co integration analysis. Co-integration results show that all gram markets are highly Co-integrated in the Long run. The high degree of market integration observed in this case is consistent with the view that Pakistan’s gram markets are quite competitive and provide little justification for extensive and costly government intervention designed to improve competitiveness to enhance market efficiency

    Genetic and genomic architecture of salt tolerance in bread wheat

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    Soil salinization is the consequence of climate change and soil salinity significantly reduces wheat yield. Therefore, development of salt tolerant wheat is a feasible option for 1 billion hectares of salt affected land and wheat breeding for this trait could be enhanced by marker assisted selection (MAS) and identification of major genes for salt tolerance. The Axiom Wheat Breeder's Genotyping Array was used to genotype 154 F2 wheat lines developed from parents with contrasting salt tolerance. A high-density genetic linkage map consisting of 988 single nucleotide polymorphisms (SNPs) markers was constructed and 49 quantitative trait loci (QTL) were mapped for salt tolerance related traits and mineral nutrients concentrations under salt stress. Two Na+ exclusion (NAX) QTLs located on chromosome 2A coincided with a major reported QTL (Nax1 or HKT1;4) while two major NAX QTLs mapped on 7A contributed 18.79 and 11.23 % to salt tolerance. Another 13 QTLs including major QTLs were mapped for K+, Ca+2 and Mg+2 concentrations while 27 novel QTLs were identified for tissue Boron, Copper, Iron, Manganese Phosphorus, Sulphur and Zinc concentrations under salinity. Several of these QTLs were validated in two mapping populations. The segregating markers were annotated/located on 1257 genes for various ion channels, transcription factors (TFs), signaling pathways, genetic and epigenetic factors, tolerance mechanisms, metabolic pathways etc. The in-silico transcriptomics analysis found 258 of these genes to be differentially expressed under salinity, another 74 genes were found to be vital for plants under both normal and saline conditions. Another 156 genes showed the expression only under salt stress while 54 of them had significant number of alignments with salt-expressed transcriptome. The transcriptomics analysis for 478 NAC, WRKY, MADS-box, AP2-containing, MYB and MYB-related TF families revealed that 181 TFs were differentially expressed under salinity in wheat. Taken together, the SNPs, QTLs, genes, transcripts and TFs identified in this study will be a valuable source for wheat breeding for salt tolerance

    Testing the law of one price in gram markets of Pakistan

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    Regional market integration in many agricultural commodities has been extensively studied for the insight, it provides in to the functioning of such markets; such studies provide valuable information about the dynamics of market adjustment, and whether there exist market imperfection, which may justify government intervention. This study used the monthly wholesale price (Rs. /40 kg) data from January 1991 to December 2006 of gram, in Logarithmic form and empirically estimated the degree of integration in gram markets of Pakistan using co integration analysis. Co-integration results show that all gram markets are highly Co-integrated in the Long run. The high degree of market integration observed in this case is consistent with the view that Pakistan’s gram markets are quite competitive and provide little justification for extensive and costly government intervention designed to improve competitiveness to enhance market efficiency

    Testing the law of one price in gram markets of Pakistan

    Get PDF
    Regional market integration in many agricultural commodities has been extensively studied for the insight, it provides in to the functioning of such markets; such studies provide valuable information about the dynamics of market adjustment, and whether there exist market imperfection, which may justify government intervention. This study used the monthly wholesale price (Rs. /40 kg) data from January 1991 to December 2006 of gram, in Logarithmic form and empirically estimated the degree of integration in gram markets of Pakistan using co integration analysis. Co-integration results show that all gram markets are highly Co-integrated in the Long run. The high degree of market integration observed in this case is consistent with the view that Pakistan’s gram markets are quite competitive and provide little justification for extensive and costly government intervention designed to improve competitiveness to enhance market efficiency

    Assessment of active pharmaceutical ingredients in drug registration procedures in Pakistan : implications for the future

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    Introduction: There are concerns over the quality of generic medicines in Pakistan. This is due to perceived non-compliance with good manufacturing practice (GMP), whereby the quality of the raw materials is not being assessed. If not addressed, this will impact on the potential for generics exports from Pakistan, as well as on patient care. Consequently, there is a need to assess the current assessment and regulatory situation in Pakistan and to recommend a way forward that ensures the future quality of products. Objective: To assess the quality of the raw materials that are either imported to, or manufactured in Pakistan, that are then used to produce a leading analgesic (ibuprofen). As part of the assessment, the presence and levels of impurities will be determined. Subsequently, the findings will be used to recommend potential regulatory changes to improve patient care. Methods: The quality of 27 sourced raw materials and the reference product were assessed using a variety of quality assessment methodologies, including assay tests, and infrared spectroscopy and UV-spectrophotometry. The calculated values were then compared to values documented in the Certificate of Analysis (CoA), and high performance liquid chromatography (HPLC). Results: All but one sample passed the spectroscopy identification tests. However, 81.5% of samples failed to comply with pharmacopoeia assay limits. There were also concerns with the use of HPLC methods used to assess the quality of raw materials, and over the fact that assay values obtained were not the same as those listed in the CoA. In addition, where manufacturers had concerns over the amount of ibuprofen in the raw material, rather than rejecting the product, they typically used higher quantities to make up any shortfall. Conclusions: The results of this study demonstrate that there is an urgent need to improve the registration process for generic products in Pakistan. This should include implementing Common Technical Documents (CTDs) based on international standards. In this way, we will see generics being produced that result in improved patient care and that have potential for export from Pakistan

    Co- DLSA: Cooperative Delay and Link Stability Aware with Relay Strategy Routing Protocol for Flying Ad-Hoc Network

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    A novel ad-hoc network called a flying ad-hoc network (FANET) has recently emerged, in which the flying nodes are referred to as unmanned aerial vehicles (UAVs) that are operated remotely live from a distance or using some determined approach in perspective of algorithms. Due to their high degree of mobility and flying nature with dynamic topology, the nodes in this network may discontinue their transmission because of transmission loss and unstable links among them. A relay node serves as an intermediary to reduce the distance of the nodes from each other as well as to boost the performance of communication. In this paper, Delay and Link Stability Aware (DLSA) and Cooperative Delay and Link Stability Aware (Co-DLSA) have been proposed as relay strategy routing schemes. Co-DLSA is an extension of the DLSA routing scheme in which the relay strategy has been introduced for cooperative routing with fair-relay-strategy (FRS) and red-black (RB) routing tree to increase the performance of the network. The main focus is to minimize the delay while minimizing transmission loss and lowering the network stability count in terms of discontinuous nodes. Through the simulation results, it has been concluded that the proposed routing protocol performs efficiently in terms of network lifetime, network delay, network packet drops, network throughput, and transmission loss compared to the existing routing protocols in this network. The average results of the simulations recorded a network stability for Co-DLSA of 18, average transmission loss was recorded as 67.72, average network delay was recorded as 23.28, average network throughput was recorded as 95.85, and network packet drop was recorded as 20.85, showing outstanding performance in comparison with all other routing protocols
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