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141.
Ian Young Lisa Waddell Javier Sanchez Barbara Wilhelm Scott A. McEwen Andrijana Rajić 《Preventive veterinary medicine》2014
Knowledge synthesis refers to the integration of findings from individual research studies on a given topic or question into the global knowledge base. The application of knowledge synthesis methods, particularly systematic reviews and meta-analysis, has increased considerably in the agri-food public health sector over the past decade and this trend is expected to continue. The objectives of our review were: (1) to describe the most promising knowledge synthesis methods and their applicability in agri-food public health, and (2) to summarize the recent advancements, challenges, and opportunities in the use of systematic review and meta-analysis methods in this sector. We performed a structured review of knowledge synthesis literature from various disciplines to address the first objective, and used comprehensive insights and experiences in applying these methods in the agri-food public health sector to inform the second objective. We describe five knowledge synthesis methods that can be used to address various agri-food public health questions or topics under different conditions and contexts. Scoping reviews describe the main characteristics and knowledge gaps in a broad research field and can be used to evaluate opportunities for prioritizing focused questions for related systematic reviews. Structured rapid reviews are streamlined systematic reviews conducted within a short timeframe to inform urgent decision-making. Mixed-method and qualitative reviews synthesize diverse sources of contextual knowledge (e.g. socio-cognitive, economic, and feasibility considerations). Systematic reviews are a structured and transparent method used to summarize and synthesize literature on a clearly-defined question, and meta-analysis is the statistical combination of data from multiple individual studies. We briefly describe and discuss key advancements in the use of systematic reviews and meta-analysis, including: risk-of-bias assessments; an overall quality-of-evidence approach; engagement of stakeholders; Bayesian, multivariate, and network meta-analysis; and synthesis of diagnostic test accuracy studies. We also highlight several challenges and opportunities in the conduct of systematic reviews (e.g. inclusion of grey literature, minimizing language bias, and optimizing search strategies) and meta-analysis (e.g. inclusion of observational studies and approaches to address the insufficient reporting of data and significant heterogeneity). Many of these developments have yet to be comprehensively applied and evaluated in an agri-food public health context, and more research is needed in this area. There is a need to strengthen knowledge synthesis capacity and infrastructure at the regional, national, and international levels in this sector to ensure that the best available knowledge is used to inform future decision-making about agri-food public health issues. 相似文献
142.
Co-residence patterns in hunter-gatherer societies show unique human social structure 总被引:2,自引:0,他引:2
Hill KR Walker RS Bozicević M Eder J Headland T Hewlett B Hurtado AM Marlowe F Wiessner P Wood B 《Science (New York, N.Y.)》2011,331(6022):1286-1289
Contemporary humans exhibit spectacular biological success derived from cumulative culture and cooperation. The origins of these traits may be related to our ancestral group structure. Because humans lived as foragers for 95% of our species' history, we analyzed co-residence patterns among 32 present-day foraging societies (total n = 5067 individuals, mean experienced band size = 28.2 adults). We found that hunter-gatherers display a unique social structure where (i) either sex may disperse or remain in their natal group, (ii) adult brothers and sisters often co-reside, and (iii) most individuals in residential groups are genetically unrelated. These patterns produce large interaction networks of unrelated adults and suggest that inclusive fitness cannot explain extensive cooperation in hunter-gatherer bands. However, large social networks may help to explain why humans evolved capacities for social learning that resulted in cumulative culture. 相似文献
143.
Photons are excellent information carriers but normally pass through each other without consequence. Engineered interactions between photons would enable applications as varied as quantum information processing and simulation of condensed matter systems. Using an ensemble of cold atoms strongly coupled to an optical cavity, we found that the transmission of light through a medium may be controlled with few photons and even by the electromagnetic vacuum field. The vacuum induces a group delay of 25 nanoseconds on the input optical pulse, corresponding to a light velocity of 1600 meters per second, and a transparency of 40% that increases to 80% when the cavity is filled with 10 photons. This strongly nonlinear effect provides prospects for advanced quantum devices such as photon number-state filters. 相似文献
144.
Zoldoš Vlatka Vidaković-Cifrek Željka Tomić Mihovil Papeš Dražena 《Water, air, and soil pollution》1997,94(1-2):181-190
Allium test has already been used to determine cytotoxicity of waste drilling fluids. In the present work the cytotoxicity of four pure chemicals (Defoamex, Idthin 400, Magco Thin and Slick Pipe) was investigated. Those chemicals are components of drilling fluids, therefore, they are usually constituents of oil and gas industry waste waters. The tested chemicals were prepared in 1:9 dilution and cytotoxic effects on root-tip meristem ofAllium ascalonicum were analysed after 24-, 48- and 72-hour-treatments. All samples showed cytotoxicity which was proved by cytogenetic parameters such as inhibition of mitotic activity and increase of mitotic abnormalities and chromosomal aberrations in comparison with the control. Almost all mitotic abnormalities induced by four chemicals tested were the result of disturbed spindle mechanisms accompanied with stickiness. Slick Pipe revealed the most prominent mitodepressive effect and induced a high number of abnormalities. It caused a significant decrease of mitotic activity and increase of mitotic abnormalities after all three treatment durations, while chemicals Defoamex and Magco Thin showed a significant decrease of mitotic activity only after 72-hour-treatment. Chemicals Defoamex, Idthin 400 and Magco Thin revealed a significant increase of mitotic abnormalities after 48- and 72-hour-treatments. 相似文献
145.
Milisavljević MDj Timotijević GS Radović SR Brkljacić JM Konstantinović MM Maksimović VR 《Journal of agricultural and food chemistry》2004,52(16):5258-5262
An 8S storage globulin from buckwheat seed, which resembles the structure and features common to the vicilin-like family of seed storage proteins, was analyzed for this paper. It was found that expression of the 8S globulin gene precedes that of the 13S globulin (the main buckwheat storage protein) and starts from an early stage of buckwheat seed development (9-11 days after flowering), continuing to accumulate throughout seed development to contribute approximately 7% of total seed proteins. This protein fraction might be more interesting for biotechnological application than the 13S buckwheat legumin consisting of 23-25 kDa subunits reported to be the major buckwheat allergen. A partial cDNA was also isolated, showing high homology with cDNAs coding for vicilin-like storage proteins from various plant species, and its expression profile throughout seed development as well as in different buckwheat tissues was analyzed. 相似文献
146.
Summary The productivity of 1-, 2-, and 3-culm plants of three winter wheat cultivars was studied under field conditions in three spatial arrangements. The treatments with 2- and 3-culm plants produced higher grain yield per unit area than the treatments with 1-culm plants. This was explained as the result of a higher interplant than intraplant competition. It seems that the interplant competition is lower with dwarf than with tall cultivars. The secondary culms may be as productive as the primary ones if there are only a few of them per plant and if they develop before the beginning of winter. If the tillering takes place mainly in spring, the differences in productivity between the primary and secondary culms are considerable. Under conditions of dry autumns and late planting not the tillering must be taken as the main factor which regulates the optimal number of spikes/m2, but the high planting rate. 相似文献
147.
Faruk Bogunić Sonja Siljak-Yakovlev Edina Muratović Fatima Pustahija Safer Medjedović 《Annals of Forest Science》2011,68(1):179-187
• Introduction
The most common representatives of the European mountain pine complex (Pinus mugo s.l.) are P. mugo s.s. and Pinus uncinata. 相似文献148.
Dragan Milić Slobodan Katić Đura Karagić Jelica Gvozdanović–Varga Sofija Petrović Jan Boćanski 《Euphytica》2011,182(1):25-33
The objective of this study was to develop diallel population hybrids by crossing selected germplasm and to determine the
gene effects and genetic control of yield and yield components using diallel analysis. A complete diallel including reciprocals
was made during 2003 and 2004 between five alfalfa cultivars of different geographic origin. For each pairwise cross, five
plants were chosen at random from each of the two cultivars (~100 florets per plant) to obtain the F1 generation. A spaced plant field was established in 2006 which included the five alfalfa cultivars (parents) and their 20
diallel hybrids (F1). The results of the diallel analysis suggest that the genetic control of major agronomic traits is determined by both additive
gene action (accumulation of frequency of desirable alleles represented by significant GCA effects) and nonadditive gene action
(complementary gene interactions represented by significant SCA effects). This type of gene action expression in alfalfa also
determines the way in which breeding is carried out and brings about changes in the methods used and has given rise to the
idea of the semi-hybrid breeding of this crop. The concept involves: breeding alfalfas within the population, identification
of heterotic germplasm, and the production of seed of the population hybrid (PH). 相似文献
149.
150.