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151.
Serafeim C. Chaintoutis Evangelos Kiossis Nektarios D. Giadinis Christos N. Brozos Corinne Sailleau Cyril Viarouge Emmanuel Bréard Maria Papanastassopoulou Stéphan Zientara Orestis Papadopoulos Chrysostomos I. Dovas 《Tropical animal health and production》2014,46(1):251-255
During March 2013, we investigated the presence and the levels of Schmallenberg virus (SBV) circulation in three dairy cow herds and three sheep flocks in Central Macedonia, Greece. In two cow herds, a high number of abortions had been observed during the winter. Six bulk-tank milk samples and 147 individual sera were screened for SBV-specific antibodies by ELISA. Positive reactions were obtained from 5 out of 6 bulk-tank milk samples, 58 out of 90 sera from the 3 cow herds, and 2 sera from 2 of the 3 sheep flocks. Twenty-two ELISA-positive sera were tested by serum neutralization test (SNT). SNT confirmed the presence of neutralizing antibodies against SBV in all samples tested, with titers ranging between 1:32 and ≥1:256. No neutralizing antibodies against Akabane virus (AKAV) or Shamonda virus (SHAV) were detected, indicating that neutralizing antibodies against SBV do not cross react with AKAV or SHAV in SNT. ELISA testing of bulk-tank milk samples proved to be convenient and reliable. None of the tested sera was found positive for SBV by real-time RT-PCR, indicating that the sampling was conducted past the viremia stage. This is the first report of SBV circulation in Greece. 相似文献
152.
Developments in breeding cereals for organic agriculture 总被引:1,自引:6,他引:1
M. S. Wolfe J. P. Baresel D. Desclaux I. Goldringer S. Hoad G. Kovacs F. Löschenberger T. Miedaner H. Østergård E. T. Lammerts van Bueren 《Euphytica》2008,163(3):323-346
The need for increased sustainability of performance in cereal varieties, particularly in organic agriculture (OA), is limited
by the lack of varieties adapted to organic conditions. Here, the needs for breeding are reviewed in the context of three
major marketing types, global, regional, local, in European OA. Currently, the effort is determined, partly, by the outcomes
from trials that compare varieties under OA and CA (conventional agriculture) conditions. The differences are sufficiently
large and important to warrant an increase in appropriate breeding. The wide range of environments within OA and between years,
underlines the need to try to select for specific adaptation in target environments. The difficulty of doing so can be helped
by decentralised breeding with farmer participation and the use of crops buffered by variety mixtures or populations. Varieties
for OA need efficient nutrient uptake and use and weed competition. These and other characters need to be considered in relation
to the OA cropping system over the whole rotation. Positive interactions are needed, such as early crop vigour for nutrient
uptake, weed competition and disease resistance. Incorporation of all characteristics into the crop can be helped by diversification
within the crop, allowing complementation and compensation among plants. Although the problems of breeding cereals for organic
farming systems are large, there is encouraging progress. This lies in applications of ecology to organic crop production,
innovations in plant sciences, and the realisation that such progress is central to both OA and CA, because of climate change
and the increasing costs of fossil fuels. 相似文献
153.
Brédas JL 《Science (New York, N.Y.)》1994,263(5146):487-488
154.
Reidar Almås 《Agriculture and Human Values》1993,10(4):2-12
The main idea of this article is to present various perspectives in order to analyze the recent crisis concerning the agriculture-based rural societies in the developed capitalist communities. In all of these countries there is a production crisis, resulting in too much food. But this is also an ideological crisis, because the consumer thinks that the food is produced at too high a price. And it is a political crisis as well because a major part of the voters think subsidies and trade barriers are too high. The paper argues that beneath the present agricultural and rural policy crisis lies the failure of three great projects of our time: 1) The project of natural science; 2) The project of liberal capitalism; and 3) The project of scientific socialism. The failure of these three projects has to do with the breakdown of the positivist idea of modernization. Modernization theory was partly wrong because it overlooked the persistence of locally based life modes. Those life modes must be understood before a sustainable rural development is found. The article reviews some contemporary social science perspectives that have recently been developed to grasp the fundamental changes of today's rural societies. Based on those perspectives and primarily the life mode perspective, five key elements that are essential to analyze if we want to understand future development are isolated: food production, resources, space, social diversity, and culture.Reidar Almås is a Professor of Sociology at the University of Trondheim, Norway, where he directs the Center for Rural Research. He received his Dr. philos. at the University of Trondheim with a dissertation on group farms. Almås is now doing research on food policies, rural development, and public perception of biotechnology. In addition to several books in Norwegian, he has publishedRural Norway, a gift to Europe. Fifteen selected articles on rural persistence and change. 相似文献
155.
The effectiveness of 2.32 mmol/kg (approximately 1000 ppm) of alpha-, gamma-, or delta-tocopherol (TOH), as well as different levels of alpha TOH, on the formation of hydroperoxides in fish oil was studied by monitoring the peroxide value (POV) and the formation of conjugated dienes (CD) during storage at 30 degrees C. The same order of antioxidant activity was observed by both methods. Linear regression of POV on CD showed that these data were strongly correlated (r(2) > or = 0.98). The value of the slope of the regression lines, however, differed substantially and decreased with increasing hydrogen-donating ability of the different tocopherols and with increasing alpha TOH concentration. It is suggested that this is due, at least in part, to the contribution from hydroxy compounds to the CD measurements and a greater contribution from hydroperoxy epidioxides (two peroxide groups per conjugated diene unit) to the POV than to the CD value. The degrees of formation of both these groups of oxidation products are expected to be influenced by the rate of scavenging of lipid peroxyl and alkoxyl radicals by tocopherol (alpha TOH > gamma TOH > delta TOH). 相似文献
156.
Dubrovinsky LS Dubrovinskaia NA Saxena SK Annersten H Hålenius E Harryson H Tutti F Rekhi S Le Bihan T 《Science (New York, N.Y.)》2000,289(5478):430-432
We have heated ferropericlases (Mg(0.60)Fe(0.40))O and (Mg(0.50)Fe(0.50))O to temperatures of 1000 kelvin at pressures of 86 gigapascals, simulating the stability of the solid solution at physical conditions relevant to Earth's lower mantle. The in situ x-ray study of the externally heated samples in a Mao-Bell-type diamond anvil cell shows that ferropericlase may dissociate into magnesium-rich and iron-rich oxide components. The result is important because the decomposition of ferropericlase into lighter and heavier phases will cause dynamic effects that could lead to mantle heterogeneity. 相似文献
157.
Reidar Almås 《Agriculture and Human Values》1989,6(1-2):127-136
This article raises the issue of the extent to which a single nation can develop a “national agricultural policy,” pursuing internal goals in agrarian development, goals that vary significantly from those of other industrialized countries. What are the conflicts arising from such a policy and how do these conflicts interfere with the general agricultural crisis of these countries? The Norwegian case is explored as an example of a blend of social-democratic and center-populist agricultural policies. The decision in 1975 by the Norwegian Parliament to establish the income level of farmers at the same level as workers is seen as an experiment. As agricultural policy, this new departure represented a deviation from the earlier policies of rationalization. The Social Democrats developed their new position as a result of internal and external pressure. A series of reforms financed by the new state incomes from oil production were undertaken, of which income equalization and a farm relief service were the most important. Most Norwegian farmers speak of the reform years as “the good years of escalation.” Equity was reached in 1982, but nevertheless several problems emerged: 1) the escalation of subsidized incomes led to overproduction and decreasing incomes from the market (after 1982), 2) the large budgetary transfers to agriculture caused a legitimation crisis, fueling the constituency of the right-wing Progress Party, 3) the large subsidies to agriculture contributed to the fiscal crisis of the state, 4) the problems mentioned above, contributed to the general crisis of the Norwegian Social Democracy which finds itself with dwindling support. The likely outcome of the present Norwegian farm crisis is the implementation of an agricultural policy that will protect the most vulnerable sector and open the more competitive sector to market forces. 相似文献
158.
S Br?ring E Müller K Petzoldt H A Schoon K C Bergmann 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1989,36(9):681-690
Models for infecting mice with Influenza A-Virus (A/PR 8/34, H0N1) and Actinobacillus pleuropneumoniae (serotype 9) were developed in Han: NMRI-mice. After infecting mice with sublethal doses of one of the infectious agents, or both together as a mixed infection, animals were subsequently exsanguinated and the lungs washed by bronchoalveolar lavage. Clinical symptoms were recorded daily, examination of lung lavage fluid and sera as well as histology of the lungs were done. An increase in mortality, weight reduction and total cell yield of lung lavage fluid was observed after mixed infection. Compared to mixed infections total protein content and elastase in sera and lung lavage fluid after singular ones were raised not as much. In lung lavage fluid the total cell yield was increased more marked. These alterations indicate a synergistic effect of viruses and bacteria, developed by mixed infection as well as a bacterial infection on top of a viral one. Histopathologically the lung alterations were found to depend on the infectious agent and the mode of infection. 相似文献
159.
160.