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1.
The article is devoted to the 100th anniversary of the outstanding world-renown Russian scientist Vladimir Alexandrovich Strunnikov, Academician, Professor, Head of Group of Developmental Cytology and Sex Regulation at Koltzov Institute of Developmental Biology and Head of genetic studies on silkworms in a number of sericulture institutes in CIS. Laureate of the State Prize of the USSR (1981), Hero of Socialist Labor (1990), awarded the I.I. Mechnikov Gold Medal, Academy of Sciences of the USSR (1981), founder of the theory explaining the origin of heterosis. One of his most significant achievements is the “Methods of Fixing the Heterosis Effect,” which makes it possible to abandon the production of hybrid seed and increase the yield of many crops by 20–50%. Fixing the gene complexes that determine the heterosis effect will become the “springboard” that will allow obtaining even more productive heterotic hybrids on the basis of new-generation varieties. The efficiency of this method in plant objects at the organismal and molecular levels was shown in the All-Russia Research Institute of Rice. A modification of this method reducing its laboriousness and increasing its efficiency was developed.  相似文献   

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《Biologicals》2010,38(1):170-177
The conclusions and recommendations from the October 2009 meeting of the Strategic Advisory Group of Experts (SAGE) on immunization have been published in the WHO weekly epidemiological record (December 11, 2009) and are reproduced with the permission.  相似文献   

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The parasite contamination make difficult laboratory cultivation of green algae and decrease significantly the production of microalgal biomass during industrial cultivation. In the present study the influence of the endogenous abscisic acid content (determinate by gas chromatography) on the host-parasite relationship in different ontogenetic phases of the host Scenedesmus as well as resistance induction after treatment of synchronous algal culture with ABA were studied. Synchronization of algae was carried out by alteration of light and dark periods. The age groups under study were: autospores (at the beginning of the light period), growing cells, mature cells (belonging to in the end of the light period) and mature cells, starting to release autospore at the beginning of dark phases. The higher levels of endogenous ABA during the algal autospore formation as well as exogenous ABA supply of (10−5 M) inhibited the infection process in the pathosystem green microalga Scenedesmus acutus and unicellular fungal parasite Phlyctidium scenedesmi. The treatment with fluridone 10−7 M (an inhibitor of ABA biosynthesis) increased the host susceptibility during all ontogenetic phases. The susceptibility of S. acutus to the chytridial infection depended on the endogenous ABA level during different ontogenetic stages of the alga.  相似文献   

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Cropping on jhum fallows in north-eartern India is predominantly done for one year in a jhum cycle. If second year cropping is done, expanse of the forest land required for slashing and burning could be reduced significantly. We tested this hypothesis in a young (6 yr) and an old (20 yr) jhum fallow. We also evaluated if the productivity during second year cropping could be alleviated by auxiliary measures such as tilling the soil or application of fertilizers (chemical or farm-yard manure or both in combination). The results demonstrate that the ecosystem productivity (total dry matter production) and economic yield (rice grain production) decline with shortening of jhum cycle. Second year cropping causes a further decline in ecosystem productivity in old jhum field, but not in young jhum field. Economic yield from second year cropping in its traditional form (without any fertilizer treatment) is not much lower than that in the first year, and can be improved further by manuring the soil. Tilling of soil improves neither ecosystem productivity nor economic yield. Different fertilization treatments respond differently; while inorganic manuring enhances ecosystem productivity, a combination of inorganic and organic manuring improves economic yield  相似文献   

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This study aims to explore families’ reflections on their decision to donate brain tissue to the NSW Tissue Resource Centre (NSW TRC), Australia. Specifically, the study aims to investigate respondents’ initial reactions to the request for donation, primary reasons for their decision, and subsequent satisfaction levels. Participants were next-of-kin (NOK) contacted between May 2002 and May 2008, on the day of their relative’s autopsy, who agreed to donate brain tissue to the NSW TRC for medical research. All 111 NOK were invited to participate, and those who agreed completed an anonymous questionnaire. Fifty completed questionnaires were received. Results showed that 74% of respondents were not upset by the donation call and 98% were satisfied with their decision to donate. Of the 22% who reported having been upset, many indicated that their distress was partly related to their circumstances. When asked the main reason for their donation, 66% had wanted to help others, or help research, while 24% stated their primary reason as a belief that they were respecting the wishes of their deceased relative. These findings show that NOK are not further distressed by being asked to donate brain tissue, give altruistic reasons for consent and are satisfied with the decision they made. In both this study and previous literature, the importance of discussion about organ donation amongst relatives is a recurring theme. Knowledge about a relative’s wishes is likely to help facilitate decision-making, overcoming at least one crucial barrier to lifting rates of organ donation for transplantation and research.  相似文献   

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In order to evaluate the impact of blood sample handling processes on circulating TGF-β1 levels, blood specimens were obtained from 13 healthy volunteers using different handling processes (kept at room temperature (RT) or on ice before centrifugation, using different centrifugal forces). TGF-β1 levels were measured using an enzyme-linked immunosorbent assay. A paired-T test was used for statistical analysis. The TGF-β1 level in on-ice serum was significantly lower than that in room-temperature serum (P<0.001), and both were significantly higher than that found in on-ice plasma (P<0.001). Compared with on-ice plasma samples, the longer the samples were kept at RT, the higher the levels of TGF-β1 in plasma (P=0.268, 0.040, and 0.0015 for 5 min, 30 min, and 60 min in RT, respectively). Compared with plasma centrifuged at 2,500×g for 30?min, the TGF-β1 levels were much lower than those found in plasma centrifuged at 1,200×g for 10?min (P=0.003); and a double centrifugation before TGF-β1 detection, significantly decreased the level (P<0.001). It is suggested that the optimal sampling conditions for the detection of TGF-β1 should be plasma prepared on ice and spun down at a higher centrifugal force.  相似文献   

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Geophagy has been hypothesized to be an adaptive behavior, either as a means to allay nutrient deficiency or to protect against ingested pathogens and toxins. Others have proposed that geophagy is non-adaptive, occurring either to allay hunger or as an epiphenomenon of nutrient deficiencies. This paper evaluates these hypotheses using 482 published cultural-level accounts of human geophagy and 330 accounts of geophagy among 297 species of mammals, birds, and reptiles. Information was extracted from reports of human geophagy to permit statistical analysis; reports of non-human geophagy were tabulated. Human geophagy did not parallel changes in nutrient requirements, occurred most frequently among children and pregnant women and in tropical areas (where pathogen densities are highest), and was associated with ingestion of toxic substances and gastrointestinal distress. Earth ingested by humans was craved and carefully selected and prepared; it had high clay content, but few bioavailable mineral nutrients. In primates, geophagy was associated with both protection from toxins and obtaining nutrients, whereas in other vertebrates it was associated mainly with obtaining nutrients. Our results indicate that human geophagy is best explained as providing protection from dietary chemicals, parasites, and pathogens, whereas animal geophagy may involve both micronutrient acquisition and protection.  相似文献   

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In the conservation of forests and protected areas, a gap lies between scientific knowledge and the management decisions made. From our perspective as scientists studying a national park, who deal daily with both research and administration, we discuss the general reasons for this gap. We provide examples (saproxylic beetles and Norway spruce genetics) to demonstrate the dilemma of practitioners who aim at basing their decisions on evidence. From our experience, the approach of problem solving is crucial, yet in many cases, the bidirectional bridge between science and application is poorly established. We specifically urge governments to organize nation-wide species distribution data; scientists to support the conservation community with new functional approaches, also in combination with Red Lists to identify diversity hotspots and major threats; stakeholders to identify land-use alternatives for scientists to study; state research institutes to increase the proportion of scientists; scientists and governmental authorities to regularly summarize scientific results and conclusions for practitioners; and agencies should foster incentives for scientists to deal with conservation efforts.  相似文献   

10.
Native to Brazil,Schinus terebinthifolius Raddi, of the family Anacardiaceae, has been commonly cultivated in Florida for over 50 years as a dooryard ornamental. Use of its sprays of showy red fruits for Christmas decoration gave rise to the popular misnomer “Florida holly.” Too late it was found to become a large, spreading tree; aggressive seedlings began springing up near and far. Jungles ofSchinus have crowded out native vegetation over vast areas of Florida and the Bahamas, as in all the islands of Hawaii. When in bloom, the tree is a major source of respiratory difficulty and dermatitis; the fruits, in quantity, intoxicate birds and cause fatal trauma in four-footed animals. The abundant nectar yields a spicy commercial honey and beekeepers are opposed to eradication programs.  相似文献   

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The second generation Intel Xeon Phi processor codenamed Knights Landing (KNL) have recently emerged with 2D tile mesh architecture and the Intel AVX-512 instructions. However, it is very difficult for general users to get the maximum performance from the new architecture since they are not familiar with optimal cache reuse, efficient vectorization, and assembly language. In this paper, we illustrate several developing strategies to achieve good performance with C programming language by carrying out general matrix–matrix multiplications and without the use of assembly language. Our implementation of matrix–matrix multiplication is based on blocked matrix multiplication as an optimization technique that improves data reuse. We use data prefetching, loop unrolling, and the Intel AVX-512 to optimize the blocked matrix multiplications. When we use a single core of the KNL, our implementation achieves up to 98% of SGEMM and 99% of DGEMM using the Intel MKL, which is the current state-of-the-art library. Our implementation of the parallel DGEMM using all 68 cores of the KNL achieves up to 90% of DGEMM using the Intel MKL.  相似文献   

13.
Ruan YJ  Zhu L  Xu XY 《Bioresource technology》2011,102(16):7599-7602
The bio-flocs technology (BFT) was applied in the sequencing batch reactor (SBR) to treat aquaculture wastewater for flocs poly-β-hydroxybutyrate (PHB) accumulation with alternant anaerobic and aerobic conditions. The statistical modeling approach was used to evaluate system performance and to optimize the flocs PHB yield at batch mode. The results show that all variables have significant impact on the response objective, as well as the interactions of the C/N ratio with the flocs biomass concentration (VSS) and anaerobic time, respectively. By process optimization, approximately 150-200 PHB/VSS (mg·g) of flocs PHB yield was achieved in the range of 4-7 g/l of flocs biomass concentration, 15-18 of the C/N ratio and 50-85 min of anaerobic time in the BFT systems. The results demonstrated that a suitable flocs PHB yield can be obtained via optimizing the ex-situ operating strategy, which have potential prebiotic value and practical implication for the sustainable aquaculture.  相似文献   

14.
Although zinc plays an important role in health status of the elderly, their dietary habits in relation to zinc intake are not well documented. The main objective of the current study was the assessment of dietary zinc intake in European old populations and the investigation of its impact on plasma zinc and inflammatory cytokines concentrations, in relation to genetic markers. Within the ZINCAGE study, 819 healthy old Europeans (≥60 years old) were recruited. Plasma zinc, interleukin-6 (IL-6) and interleukin-8 (IL-8) were measured. Genotype data were obtained for the ?174G/C polymorphism in the IL-6 gene. Dietary data were collected with a food frequency questionnaire and were used to calculate a zinc diet score. Zinc score was validated using additional dietary data (24-h recalls), in a subsample of 105 subjects. Zinc score was different among most of the European centres (P<.001), while an age-dependent decline was documented (P=4.4×10?12). Plasma zinc concentrations were significantly correlated with the zinc score (standardized β=0.144, P=8.8×10?5). The minor allele frequency for the ?174G/C polymorphism was f(C) 0.31. There was a significant interaction of zinc diet score and GG (?174G/C) genotype on higher plasma IL-6 levels (β±S.E.=0.014±0.0, P=.008). The main finding of our study was the detection of gene–nutrient and biochemical–nutrient interactions in a multiethnic cohort based on a common dietary assessment tool.  相似文献   

15.
Verstraeten  G.  Van Rompaey  A.  Poesen  J.  Van Oost  K.  Govers  G. 《Hydrobiologia》2003,494(1-3):153-158
High loads of suspended sediment derived from surface water erosion processes are a major source of environmental and economic problems throughout the world. In many places, a reduction in the amount of sediment delivered from arable land to rivers has therefore become a major issue in environmental policy. In Flanders (Belgium), policy makers would like to achieve a reduction in soil erosion and sediment delivery through the use of various control measures adopted under an integrated environmental watershed management program. A distributed modelling approach (SEDEM/WaTEM) showed that although end-of-the-pipe solutions such as buffer strips or sediment retention ponds have a direct impact on sediment delivery, on-site soil conservation measures were more effective in reducing sediment loads in rivers. It remains questionable, however, whether the significant impact that watershed management has on local sediment yields, can be extrapolated to larger river drainage basins. In the case of highly regulated and channelized rivers, the impact may be much higher compared to natural rivers.  相似文献   

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Humans are at risk from exposure to extremes in their environment, yet there is no consistent way to fully quantify and understand the risk when considering more than just meteorological variables. An outdoor ‘bio-comfort’ threshold is defined for Melbourne, Australia using a combination of heat stress, air particulate concentration and grass pollen count, where comfortable conditions imply an ideal range of temperature, humidity and wind speed, acceptable levels of air particulates and a low pollen count. This is a new approach to defining the comfort of human populations. While other works have looked into the separate impacts of different variables, this is the first time that a unified bio-comfort threshold is suggested. Composite maps of surface pressure are used to illustrate the genesis and evolution of the atmospheric structures conducive to an uncomfortable day. When there is an uncomfortable day due to heat stress conditions in Melbourne, there is a high pressure anomaly to the east bringing warm air from the northern interior of Australia. This anomaly is part of a slow moving blocking high originating over the Indian Ocean. Uncomfortable days due to high particulate levels have an approaching cold front. However, for air particulate cases during the cold season there are stable atmospheric conditions enhanced by a blocking high emanating from Australia and linking with the Antarctic continent. Finally, when grass pollen levels are high, there are northerly winds carrying the pollen from rural grass lands to Melbourne, due to a stationary trough of low pressure inland. Analysis into days with multiple types of stress revealed that the atmospheric signals associated with each type of discomfort are present regardless of whether the day is uncomfortable due to one or multiple variables. Therefore, these bio-comfort results are significant because they offer a degree of predictability for future uncomfortable days in Melbourne.  相似文献   

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