1,143 research outputs found

    Development of Threshold Levels and a Climate-Sensitivity Model of the Hydrological Regime of the High-Altitude Catchment of the Western Himalayas, Pakistan

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    Water shortages in Pakistan are among the most severe in the world, and its water resources are decreasing significantly due to the prevailing hydro-meteorological conditions. We assessed variations in meteorological and hydrological variables using innovative trend analysis (ITA) and traditional trend analysis methods at a practical significance level, which is also of practical interest. We developed threshold levels of hydrological variables and developed a non-parametric climate-sensitivity model of the high-altitude catchment of the western Himalayas. The runoff of Zone I decreased, while the temperature increased and the precipitation increased significantly. In Zone II, the runoff and temperature increased but the precipitation decreased. A two-dimensional visualization of the PardĂ© coefficient showed extreme drought events, and indicated greater sensitivity of the hydrological regime to temperature than to precipitation. The threshold levels of runoff for Zones I and II were 320 and 363 mm using the Q80 fixed method, while the mean runoff amounts were estimated to be 79.95 and 55.61 mm, respectively. The transient threshold levels varied by month, and the duration of droughts in Zones I and II ranged from 26.39 to 78.98 days. The sensitivity of the hydrological regime was estimated based on a modified climate-elasticity model (Δp = 0.11–0.23, Δt = −0.04–2.39) for Zones I and II, respectively. These results highlight the sensitivity of the hydrological regime to temperature, which influences the melting process. However, it is important to establish thresholds for hydrological variables and understand the climate sensitivity of the hydrological regime of the entire basin, so that policy makers and water managers can make sustainable water-resource-management decisions for this region

    Online Information Searching Techniques: An Investigation from Library Science Professionals

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    The purpose of this study is to identify the effective information retrieval techniques used by the library and information science professionals/librarians to successfully retrieve the required information from various online information sources. This study also investigates the opinion of information professionals about various useful online information resources which are helpful during research work. It highlights various advanced searching techniques used for retrieving precise results from various online information sources i.e. search engines, databases, repositories, digital libraries, online journals, websites, etc. In this study, a quantitative research method has been used by adopting a survey research design. The population of the study was 370 information professionals working as a librarian in various public and private sector universities of Punjab. Data was successfully obtained from 278 respondents by using a questionnaire and analyzed through SPSS software. The respondents identified various sources of information that are useful to find scholarly information. These sources include e-journals, HEC databases, digital libraries, Google Scholar, digital archives, etc. They identified various useful techniques to effectively formulate a search query and apply advanced searching techniques to retrieve the desired information. This study is highly useful for libraries to increase online information resources which are useful for research students and faculty. The results of this research are also useful for early-career librarians, faculty members, and researchers to understand online search techniques and successfully retrieve the required information for research and educational tasks

    Achieving Robust Self-Management for Large-Scale Distributed Applications

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    Autonomic managers are the main architectural building blocks for constructing self-management capabilities of computing systems and applications. One of the major challenges in developing self-managing applications is robustness of management elements which form autonomic managers. We believe that transparent handling of the effects of resource churn (joins/leaves/failures) on management should be an essential feature of a platform for self-managing large-scale dynamic distributed applications, because it facilitates the development of robust autonomic managers and hence improves robustness of self-managing applications. This feature can be achieved by providing a robust management element abstraction that hides churn from the programmer. In this paper, we present a generic approach to achieve robust services that is based on finite state machine replication with dynamic reconfiguration of replica sets. We contribute a decentralized algorithm that maintains the set of nodes hosting service replicas in the presence of churn. We use this approach to implement robust management elements as robust services that can operate despite of churn. Our proposed decentralized algorithm uses peer-to-peer replica placement schemes to automate replicated state machine migration in order to tolerate churn. Our algorithm exploits lookup and failure detection facilities of a structured overlay network for managing the set of active replicas. Using the proposed approach, we can achieve a long running and highly available service, without human intervention, in the presence of resource churn. In order to validate and evaluate our approach, we have implemented a prototype that includes the proposed algorithm

    Foliar boron spray for improved yield, oil quality and water use efficiency in water stressed sunflower

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    Boron (B) is a mineral considered essential for improving sunflower (Helianthus annuus L.) resistance to drought. B supplements (0, 15-, 30- and 45 mg L-1) under well-watered and variable water deficit levels (64 and 53 mm irrigation depths) were evaluated for their effects on growth, oil quality and water use efficiency (WUE) in a field study for two consecutive years (i.e. 2011 and 2012). The duration of 50% inflorescence emergence, 50% flowering and 50% maturity stages were reduced with increasing moisture stress. All B application rates improved sunflower growth compared to no B control treatment. The moisture deficit treatments of 64 and 53 mm irrigation depths significantly (p<0.05) reduced the yield-related components. Achenes/head, achenes weight and achene yield under water stress conditions were considerably improved by foliar application of B at 30 mg L-1. An increase in protein contents and a decrease in oil contents were observed with B foliar application under moisture deficit treatments. Foliar application of B (30 mg L-1) on water stressed plants also resulted in increased WUE. The highest net benefits were achieved with B concentration of 30 mg L-1 under well-watered and mild deficit water level of 64 mm irrigation depth. The highest application rate of B (45 mg L-1) gave the best results at the most severe water deficit level. In conclusion, the B rates of 30 and 41 mg L-1 performed best for improving drought tolerance in terms of higher sunflower productivity under mild and higher water deficit conditions

    A Comparative Analysis of Unicast Routing Protocols for MPLS-VPN

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    MPLS-VPN technology is introduced to provide secure transmission with minimum propagation delay. This paper presents a comparative analysis of unicast routing protocols for MPLSVPN enabled networks. The motive behind this analysis is to observe the consequence of unicast routing protocols on the performance of MPLS-VPN enabled networks and to choose most suitable routing protocol for such type of networks. To conduct the analysis, a test bed is established in GNS3 simulator. Three main unicast routing protocols i.e. Enhanced Interior Gateway Routing Protocol (EIGRP), Open Shortest Path First (OSPF) and Routing Information Protocol (RIP) has been considered in this work. Round-Trip-Time, Jitter and Administrative-distance are used as performance measure metrics. The experimental analysis indicates that EIGRP is the most suitable protocol among the aforementioned protocols for MPLS-VPN

    A Contribution to the Previous Study for Genus Agaricus in and around Ayubia National Park, Pakistan

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    Agaricus is among the most valuable and familiar genera belonging to Basidiomycota. These are known to have a partial veil on their stipe, which helps to protect the gills when they are immature. Escalating human activity and distribution pattern of the species has introduced some new one in the territory while pushing the previously reported one to extinction. Ayubia Nationa Park always remains a suitable place for mushroom hunters and number of species of plants and fungi has already been reported. The present survey was aimed at improving the previous collection and also to check the certain characters of the genus Agaricus. Keywords: Genus Agaricus, Ayubia National Par

    Does Job Satisfaction Predict Organizational Commitment? An Information Professionals’ Perspective

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    This study examined the relationship between job satisfaction and organizational commitment among information professionals working at university libraries in Pakistan. A cross-sectional survey using a questionnaire was conducted. The questionnaire contained items related to job satisfaction and organizational commitment along with demographic variables. All the professionals working in university libraries of Punjab and Islamabad were considered as study population. It was decided to collect data from all these professionals. The questionnaire was administered either through personal visits or through email. A total of 329 questionnaires retuned which were used for data analysis. Descriptive and inferential statistics were applied for data analysis. The results revealed job satisfaction appeared to be a statistically significant but positive predictor of organization commitment among survey participants. The facets such as promotion, supervision, and job itself also appeared to be the positive correlative of overall organizational commitment. Conversely, the three facets of job satisfaction pay, fringe benefits and colleagues were not significantly correlated with overall organizational commitment as well as with all its facets. These results are useful for human resource departments of universities who work strategically for retention of satisfied and productive employees for their institutions. This study would make worthy contribution in the existing research on library management

    Phytochemical analysis, antimicrobial, antioxidant and enzyme inhibitory activities of ethanolic extract of Centaurea solstitialis L. and its different fractions

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    396-403Resistance to conventional antimicrobial regimes is one of the issues of concern in healthcare and it drives the need for development of new antimicrobial agents. Medicinal plants, as rich source of biochemical and bioactive compounds, serve as potential source for new drugs. Here, we evaluated the ethanolic extract of Centaurea solstitialis L. and its different fractions (n-hexane, choloroform and n-butanol soluble fraction) for antimicrobial, antioxidant and enzymes inhibitory activities. Antibacterial activity against two Gram-positive and three Gram-negative bacteria species were determined by using agar well diffusion and 96-wells microplate methods. Similarly, antifungal activity against two fungal strains was also evaluated by agar well diffusion method. Antioxidant activity analyzed by measuring the scavenging activity of DPPH radicals and acetylcholinesterase, butrylcholinesterase and chymotrypsin inhibitory activity was determined at 10 ”g/mL and 1.0 mg/mL concentrations. Results revealed that the ethanolic extract of C. solstitialis and its different fractions possesses significant (P<0.05) antibacterial activity and effective against fungi Aspergillus niger and Macrophomina phaseolina. Significant (P<0.05) DPPH scavenging activity (88.52±0.23%) among all fractions was noted. n-Butanol fraction showed significant acetyl-cholinesterase (78.55±0.76%) and butrylcholinesterase inhibitory activity (78.1±0.41%) with IC50 values of 54.6±0.39 ”g/mL and 211.9±0.15 ”g/mL, respectively. Maximum chymotrypsin inhibition activity was shown by crude ethanolic extract (87.76±1.17) with IC50 value of 38.23±0.75 ”g/mL. It is concluded that C. solstitialis extract and its fractions possess significant antimicrobial, antioxidant and enzyme inhibitory activity

    Marker Assisted Selection for Relative Water Content, Excised leaf Water Loss and Cell Membrane Stability in Cotton

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    Background: Drought stress is a major limitation in agricultural productivity. In cotton, drought tolerance is a multi-genic trait. The quantitative trait loci (QTLs), conferring drought tolerance in cotton, could be exploited for stress breeding using marker assisted selection.Methods: We have screened drought related varieties of Pakistan using DNA markers to identify reported QTLs for drought tolerance. A total of 44 of these varieties were selected. All varieties were sown in the field to record relative water content, excised leaf water loss and cell membrane stability under drought stress condition. QTLs for relative water content, excised leaf water loss and cell membrane stability were checked from all varieties by using DNA markers NAU-2954, NAU-2715, NAU-6672, NAU-8406 and NAU-6790.Results: Genotypic and phenotypic results showed that the QTL for relative water content qtlRWC-1 present on chromosome 23, linked marker NAU-2954, could be a major QTL conferring drought tolerance in cotton. Using Marker Assisted Selection the variety CRIS-134 showed all concerned QTLs for drought tolerance.Conclusion: QTL for relative water content qtlRWC-1 could be a major QTL for drought stress tolerance in cotton. The variety CRIS-134 may be used for breeding drought tolerant cultivar
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