1,721,320 research outputs found
Role of Extension Services in Enhancing Efficiency of Market Oriented Dairy Farmers: An Evidence from Punjab, Pakistan
No full textAgricultural extension programmes are the main source of disseminating technical information to farmers which enhance their skills and in turn farm productivity. Livestock sector in the main sub sector of agriculture in Pakistan that contributes nearly 60% to agricultural value addition. In this study, we investigated the effects of extension services on market oriented dairy farms’ technical efficiency in Pakistan. The data was collected from 345 dairy farmers of Punjab through field survey. By employing the stochastic frontier approach, it was found that on an average 85% dairy farms are technically efficient, indicating that output can be increased by 15% by enhancing the efficiency of the dairy farms. The study reveals that extension services enhance the technical efficiency of dairy farmers by imparting better management and disease control skills. Extended extension services are recommended, alongside quality training programmes and the provision of improved crossbred cattle and buffalos to ensure good quality breeds
Inorganic carbon losses by soil acidification jeopardize global efforts on carbon sequestration and climate change mitigation
No full textSoil plays a significant role in controlling the global carbon (C) cycle. Studies on climate change mitigation have focused entirely on soil organic carbon (SOC) to increase C sequestration and decrease carbon dioxide (CO2) emissions. In contrast, the contribution of soil inorganic carbon (SIC) to CO2 emissions is usually neglected because SIC is generally considered to be very stable. However, the significant worldwide increase in soil acidification, mainly because of higher N fertilization and atmospheric deposition, causes a considerable decrease in SIC stocks, leading to very high unaccounted CO2 efflux. Additionally, large areas of acidic soils worldwide are regularly subjected to high SIC applications in the form of lime to remediate acidity, which is another direct source of CO2 emission. Consequently, global efforts to mitigate climate change through SOC sequestration need a revisit as SIC-borne C losses are significant both in terms of C stocks and soil fertility loss, upon which future SOC sequestration will be reduced. Compared to SOC, wherein C stocks can be increased through management, SIC losses are irreversible and cause significant decline in soil health, ecosystem services, and functions. The present review is the first to summarize the current information about acidification-induced intensified SIC losses and their mechanisms. It included: (i) natural and anthropogenic sources and causes of soil acidification, (ii) losses of SIC as HCO3− leaching and CO2 efflux from calcareous soils (7.5 Tg C yr−1) and liming (273 Tg C yr−1) during acidity neutralization, (iii) the relationship between climate change and SIC stocks, (iv) consequences of SIC depletion in soil-plant-water systems, and (v) strategies to remediate and control soil acidification. We concluded that acidification-induced SIC-borne CO2 losses are a major C loss pathway and could jeopardize global efforts to mitigate climate change through SOC sequestration
Resilient TCP variant enabling smooth network updates for software defined data center networks
Full text linkNetwork updates have become increasingly prevalent since the broad adoption of software-defined networks (SDNs) in data centers. Modern TCP designs, including cuttingedge TCP variants DCTCP, CUBIC, and BBR, however, are not resilient to network updates that provoke flow rerouting. In this paper, we first demonstrate that popular TCP implementations perform inadequately in the presence of frequent and inconsistent network updates because inconsistent and frequent network updates result in out-of-order packets and packet drops induced via transitory congestion and lead to serious performance deterioration. We look into the causes and propose a network update-friendly TCP (NUFTCP), which is an extension of the DCTCP variant, as a solution. Simulations are used to assess the proposed NUFTCP. Our findings reveal that NUFTCP can more effectively manage the problems of out-of-order packets and packet drops triggered in network updates and it outperforms DCTCP considerably
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Simple and robust ion-selective electrodes for bio/environmental analysis
Full text linkChemical sensors have gone through a lot of optimisation renaissance over the years to have come from a typical bench-top tool for measurements of ions in standard solutions, to a more promising analytical technique capable of measuring the activities of free un-complexed nutrients in environmentally and biologically important samples. With various health issues arising due to the increasing anthropogenic contributions of man to the environment amongst other factors, and due to the need for more routine analysis especially do-it-yourself (DIY) of several analytes in physiological samples for clinical purposes, it is therefore imperative that simple, cheap, but robust sensors are developed, and optimised to meet these emerging needs.First part of this work involved fabricating solid-contact ion selective electrodes (SC-ISEs) based on the mechanical abrasion of graphite on easily modified acetate paper. Similarly results from the impedance spectra and the water layer test for electrodes with or without a conducting polymer (CP) layer indicated the suitability of the procedure. The fabricated paper electrodes importantly showed fast response time and great potential stability over the course of fourteen days. The same fabrication methodology was used to produce stable and functional solid-state paper reference electrode, and then, combined with other graphite-based paper ISEs to yield a single-strip solid contact electrode for simultaneous measurements of nitrate and ammonium in environmental samples. Satisfactory results from the comparison of measured concentrations by potentiometry and standard reference methods indicated this simplified electrode platform, designed from household materials can be used as a cheaper alternative to other solid contact electrodes.Subsequent works in this thesis involved the application of the fabricated SC-ISEs in optimization of measurement procedures of environmentally important nutrients and biologically important analytes.Routine monitoring of reactive nitrogen Nr (majorly NH4+ and NO3-) in environmental samples including soils from major land types is important to soil management system. In achieving a relatively rapid turn-around time of analysis, inorganic N species were extracted from various soil types using a single extracting solution (0.1 M MgSO4). Extractable-NH4+ and -NO3- in soils, and bioavailable NH4+ and NO3- in water samples measured concurrently using paper ISEs showed similar results to standard analytical methods.The analysis of urinary iodine (UI) is important to the public health due to serious health issues attached to its deficiency. As a result, iodide-selective electrodes based on [9] Mercuracarborand-3 (MC3) and [12] Mercuracarborand-4 (MC4) as ionophores, and NPOE and DOS as plasticizers were developed with a view to evaluate the concentration of iodide in urine.However, ion-selective electrodes (ISEs) are one of the very few experimental techniques whose limit of detection (LOD) is not defined as signal-to-noise ratio. As a result, the Bayesian model was applied to estimate the activities of nitrate and ammonium in soil and water samples, and iodide in urine samples. While the Bayesian estimates for nitrate and ammonium ions were satisfactory, significant discrepancy of estimated results for iodide in urine shows more work needs to be done in relation to designing more selective ionophores to complement non-linear approaches
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