177 research outputs found

    Effects of supplemental conjugated linoleic acids (CLA) on fresh and post‐thaw sperm quality of Holstein bulls

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    P. 459-467This study was designed to investigate the effects of feeding‐protected conjugated linoleic acid (CLA) on the semen production and sperm freezability in Holstein bulls. Twelve bulls were randomly assigned to two groups (n = 6 per group). Bulls received the normal diet (control group) or the normal diet top‐dressed with 50 g of CLA (treated group) for 10 weeks. The control group received 40 g/day calcium soap of fatty acid. Fresh and post‐thaw semen quality was assessed on ejaculates collected at the 0, 4, 6, 8 and 10 week of supplementation. Semen evaluations including sperm concentration, motion characteristics (subjective and computer‐assisted), viability (Eosin–Nigrosin), membrane integrity (hypo‐osmotic swelling test) and abnormality were conducted. Semen volume, sperm concentration and total sperm output were not affected by dietary treatment (p > .05). The proportion of spermatozoa with abnormal morphology in fresh semen significantly increased (p < .05) in the CLA‐fed group compared to control group. Also, in CLA‐fed group, the proportion of post‐thaw spermatozoa with abnormal morphology at week 10 of trial was significantly higher in CLA than control group (p < .05). Progressive motility tended to be increased in the CLA‐fed group, although dietary supplementation did not affect other CASA parameters or viability in fresh and frozen‐thawed sperm. In this study, CLA supplementation had little positive effect on fresh or post‐thaw sperm quality of Holstein bulls.S

    Bio-nanotechnology application in wastewater treatment

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    The nanoparticles have received high interest in the ïŹeld of medicine and water puriïŹcation, however, the nanomaterials produced by chemical and physical methods are considered hazardous, expensive, and leave behind harmful substances to the environment. This chapter aimed to focus on green-synthesized nanoparticles and their medical applications. Moreover, the chapter highlighted the applicability of the metallic nanoparticles (MNPs) in the inactivation of microbial cells due to their high surface and small particle size. Modifying nanomaterials produced by green-methods is safe, inexpensive, and easy. Therefore, the control and modiïŹcation of nanoparticles and their properties were also discussed

    Knowledge transfer in Tehran University of Medical Sciences: an academic example of a developing country

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    <p>Abstract</p> <p>Background</p> <p>In the past two decades, scientific publications in Iran have considerably increased their medical science content, and the number of articles published in ISI journals has doubled between 1997 and 2001. The aim of the present study was to determine how frequently knowledge transfer strategies were applied in Tehran University of Medical Sciences (TUMS). We were also interested in studying the determining factors leading to the type of strategy selected.</p> <p>Methodology</p> <p>All TUMS research projects that had received grants from inside and outside the university in 2004, and were completed by the end of 2006, were included in the study. In total, 301 projects were examined, and data on each of the projects were collected by the research team using a standardized questionnaire. The projects' principle investigators filled out a second questionnaire. In all, 208 questionnaires were collected.</p> <p>Results</p> <p>Researchers stated being more engaged in the passive strategies of knowledge transfer, especially those publishing in peer-reviewed journals. The mean score for the researchers' performance in passive and active strategies were 22% and 9% of the total score, respectively. Linear regression analysis showed that the passive strategy score decreased with the increase in the number of years working as a professional (p = 0.01) and personal interest as the only reason for choosing the research topic (p = 0.01). Regarding the active strategies of knowledge transfer, health system research studies significantly raised the score (p = 0.02) and 'executive responsibility' significantly lowered it (p = 0.03).</p> <p>Conclusion</p> <p>As a study carried out in a Middle Eastern developing country, we see that, like many other universities in the world, many academicians still do not give priority to active strategies of knowledge transfer. Therefore, if 'linking knowledge to action' is necessary, it may also be necessary to introduce considerable changes in academic procedures and encouragement policies (<it>e.g.</it>, employment and promotion criteria of academic members).</p

    Knowledge transfer in Tehran University of Medical Sciences: an academic example of a developing country

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    <p>Abstract</p> <p>Background</p> <p>In the past two decades, scientific publications in Iran have considerably increased their medical science content, and the number of articles published in ISI journals has doubled between 1997 and 2001. The aim of the present study was to determine how frequently knowledge transfer strategies were applied in Tehran University of Medical Sciences (TUMS). We were also interested in studying the determining factors leading to the type of strategy selected.</p> <p>Methodology</p> <p>All TUMS research projects that had received grants from inside and outside the university in 2004, and were completed by the end of 2006, were included in the study. In total, 301 projects were examined, and data on each of the projects were collected by the research team using a standardized questionnaire. The projects' principle investigators filled out a second questionnaire. In all, 208 questionnaires were collected.</p> <p>Results</p> <p>Researchers stated being more engaged in the passive strategies of knowledge transfer, especially those publishing in peer-reviewed journals. The mean score for the researchers' performance in passive and active strategies were 22% and 9% of the total score, respectively. Linear regression analysis showed that the passive strategy score decreased with the increase in the number of years working as a professional (p = 0.01) and personal interest as the only reason for choosing the research topic (p = 0.01). Regarding the active strategies of knowledge transfer, health system research studies significantly raised the score (p = 0.02) and 'executive responsibility' significantly lowered it (p = 0.03).</p> <p>Conclusion</p> <p>As a study carried out in a Middle Eastern developing country, we see that, like many other universities in the world, many academicians still do not give priority to active strategies of knowledge transfer. Therefore, if 'linking knowledge to action' is necessary, it may also be necessary to introduce considerable changes in academic procedures and encouragement policies (<it>e.g.</it>, employment and promotion criteria of academic members).</p

    A modified empirical criterion for strength of transversely anisotropic rocks with metamorphic origin

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    A modified empirical criterion is proposed to determine the strength of transversely anisotropic rocks. In this regard, mechanical properties of intact anisotropic slate obtained from three different districts of Iran were taken into consideration. Afterward, triaxial rock strength criterion introduced by Rafiai was modified for transversely anisotropic rocks. The criterion was modified by adding a new parameter α for taking the influence of strength anisotropy into consideration. The results obtained have shown that the parameter α can be considered as the strength reduction parameter due to rock anisotropy. The modified criterion was compared to the modified Hoek–Brown (Saroglou and Tsiambaos) and Ramamurthy criteria for different anisotropic rocks. It was concluded that the criterion proposed in this paper is a more accurate and precise criterion in predicting the strength of anisotropic rocks

    How should we assess knowledge translation in research organizations; designing a knowledge translation self-assessment tool for research institutes (SATORI)

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    <p>Abstract</p> <p>Background</p> <p>The knowledge translation self-assessment tool for research institutes (SATORI) was designed to assess the status of knowledge translation in research institutes. The objective was, to identify the weaknesses and strengths of knowledge translation in research centres and faculties associated with Tehran University of Medical Sciences (TUMS).</p> <p>Methods</p> <p>The tool, consisting of 50 statements in four main domains, was used in 20 TUMS-affiliated research centres and departments after its reliability was established. It was completed in a group discussion by the members of the research council, researchers and research users' representatives from each centre and/or department.</p> <p>Results</p> <p>The mean score obtained in the four domains of 'The question of research', 'Knowledge production', 'Knowledge transfer' and 'Promoting the use of evidence' were 2.26, 2.92, 2 and 1.89 (out of 5) respectively.</p> <p>Nine out of 12 interventional priorities with the lowest quartile score were related to knowledge transfer resources and strategies, whereas eight of them were in the highest quartile and related to 'The question of research' and 'Knowledge production'.</p> <p>Conclusions</p> <p>The self-assessment tool identifies the gaps in capacity and infrastructure of knowledge translation support within research organizations. Assessment of research institutes using SATORI pointed out that strengthening knowledge translation through provision of financial support for knowledge translation activities, creating supportive and facilitating infrastructures, and facilitating interactions between researchers and target audiences to exchange questions and research findings are among the priorities of research centres and/or departments.</p

    The performance of stochastic designs in wellbore drilling operations

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    © 2018, The Author(s). Wellbore drilling operations frequently entail the combination of a wide range of variables. This is underpinned by the numerous factors that must be considered in order to ensure safety and productivity. The heterogeneity and sometimes unpredictable behaviour of underground systems increases the sensitivity of drilling activities. Quite often the operating parameters are set to certify effective and efficient working processes. However, failings in the management of drilling and operating conditions sometimes result in catastrophes such as well collapse or fluid loss. This study investigates the hypothesis that optimising drilling parameters, for instance mud pressure, is crucial if the margin of safe operating conditions is to be properly defined. This was conducted via two main stages: first a deterministic analysis—where the operating conditions are predicted by conventional modelling procedures—and then a probabilistic analysis via stochastic simulations—where a window of optimised operation conditions can be obtained. The outcome of additional stochastic analyses can be used to improve results derived from deterministic models. The incorporation of stochastic techniques in the evaluation of wellbore instability indicates that margins of the safe mud weight window are adjustable and can be extended considerably beyond the limits of deterministic predictions. The safe mud window is influenced and hence can also be amended based on the degree of uncertainty and the permissible level of confidence. The refinement of results from deterministic analyses by additional stochastic simulations is vital if a more accurate and reliable representation of safe in situ and operating conditions is to be obtained during wellbore operations.Published versio

    Prevalence and genetic diversity of Avipoxvirus in house sparrows in Spain

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    Avipoxvirus (APV) is a fairly common virus affecting birds that causes morbidity and mortality in wild and captive birds. We studied the prevalence of pox-like lesions and genetic diversity of APV in house sparrows (Passer domesticus) in natural, agricultural and urban areas in southern Spain in 2013 and 2014 and in central Spain for 8 months (2012±2013). Overall, 3.2% of 2,341 house sparrows visually examined in southern Spain had cutaneous lesions consistent with avian pox. A similar prevalence (3%) was found in 338 birds from central Spain. Prevalence was higher in hatch-year birds than in adults. We did not detect any clear spatial or temporal patterns of APV distribution. Molecular analyses of poxvirus-like lesions revealed that 63% of the samples were positive. Molecular and phylogenetic analyses of 29 DNA sequences from the fpv167 gene, detected two strains belonging to the canarypox clade (subclades B1 and B2) previously found in Spain. One of them appears predominant in Iberia and North Africa and shares 70% similarity to fowlpox and canarypox virus. This APV strain has been identified in a limited number of species in the Iberian Peninsula, Morocco and Hungary. The second one has a global distribution and has been found in numerous wild bird species around the world. To our knowledge, this represents the largest study of avian poxvirus disease in the broadly distributed house sparrow and strongly supports the findings that Avipox prevalence in this species in South and central Spain is moderate and the genetic diversity low.This study was funded by the Spanish Ministry of Science and Innovation (Project CGL2010-15734/BOS), the Spanish Ministry of Economy and Competitiveness (Project CGL2013-41642-P/BOS) and the Innovation and Development Agency of Andalusia (Spain) (P11-RNM-7038). Grants were awarded to JMP (Juan de la Cierva- JCI-2012-11868) and MAJM (FPIBES-2011-047609), Spanish Ministry of Economy and Competitiveness; RAJW (CEI-PICATA2012), CEI Campus of International Excellence; MM (FPU12/0568), Spanish Ministry of Education, Culture and Sports. RAJW was supported by the Craaford Foundation (grant 20160971) during the writing of this publication. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    MinerĂ­a de datos para el descubrimiento de patrones en enfermedades respiratorias en BogotĂĄ, Colombia

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    Trabajo de InvestigaciĂłnEl presente proyecto se basa en la aplicaciĂłn de minerĂ­a de datos mediante el algoritmo de clustering K- means que permita la generaciĂłn de un modelo descriptivo con el anĂĄlisis de los datos y con el objetivo de identificar posibles comportamientos en enfermedades respiratorias en la ciudad de BogotĂĄ. El conjunto de clĂșsteres generados por la herramienta RapidMiner es la recopilaciĂłn de datos de un periodo de cinco años de 2012 a 2016, en donde se contemplan el nĂșmero de casos asociados a 184 diagnĂłsticos de enfermedades respiratorias y la edad de los pacientes corresponde de 0 a 5 años.Trabajo de InvestigaciĂłn1. GENERALIDADES 2. OBJETIVOS 3. JUSTIFICACIÓN 4. DELIMITACIÓN 5. MARCO REFERENCIAL 6. METODOLOGÍA 7. FUENTES DE EXTRACCIÓN Y SUS VARIABLES 8. DISEÑO 9. SELECCIÓN DE ALGORITMOS DE CLUSTERING 10. RECONOCER PATRONES A PARTIR DE LA INFORMACIÓN RECOPILADA 11. CONCLUSIONES 12. TRABAJOS FUTUROS 13. REFERENCIAS BIBLIOGRÁFICAS 14. ANEXOSPregradoIngeniero de Sistema

    Sediment source fingerprinting: benchmarking recent outputs, remaining challenges and emerging themes

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    Abstract: Purpose: This review of sediment source fingerprinting assesses the current state-of-the-art, remaining challenges and emerging themes. It combines inputs from international scientists either with track records in the approach or with expertise relevant to progressing the science. Methods: Web of Science and Google Scholar were used to review published papers spanning the period 2013–2019, inclusive, to confirm publication trends in quantities of papers by study area country and the types of tracers used. The most recent (2018–2019, inclusive) papers were also benchmarked using a methodological decision-tree published in 2017. Scope: Areas requiring further research and international consensus on methodological detail are reviewed, and these comprise spatial variability in tracers and corresponding sampling implications for end-members, temporal variability in tracers and sampling implications for end-members and target sediment, tracer conservation and knowledge-based pre-selection, the physico-chemical basis for source discrimination and dissemination of fingerprinting results to stakeholders. Emerging themes are also discussed: novel tracers, concentration-dependence for biomarkers, combining sediment fingerprinting and age-dating, applications to sediment-bound pollutants, incorporation of supportive spatial information to augment discrimination and modelling, aeolian sediment source fingerprinting, integration with process-based models and development of open-access software tools for data processing. Conclusions: The popularity of sediment source fingerprinting continues on an upward trend globally, but with this growth comes issues surrounding lack of standardisation and procedural diversity. Nonetheless, the last 2 years have also evidenced growing uptake of critical requirements for robust applications and this review is intended to signpost investigators, both old and new, towards these benchmarks and remaining research challenges for, and emerging options for different applications of, the fingerprinting approach
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