分类： 管理学 >> 管理学其他学科 提交时间： 2022-11-25 合作期刊: 《Economics & Management Review》
摘要： Agricultural green sustainable development has become an important strategy in every country, and whether this strategy can be realized depends on the development and popularization of the model of planting and breeding combined circular agriculture. Based on the related theories, a three-dimensional structure analysis model including the types of participants, project operation mode, planting and breeding structure and benefit is established in this paper. And by examining the typical case of green agriculture in China, in this study, three green farming models, namely, the animal-plant cycle model dominated by two agents, the three-dimensional cycle model with multi agents, and the three-stage cycle model dominated by individual investors, were summarized. Finally, through the comparison and induction of the models, the existing problems and optimization direction of the current basic models of planting and breeding cycle agriculture were put forward.
分类： 核科学技术 >> 裂变堆工程技术 提交时间： 2023-06-18 合作期刊: 《Nuclear Science and Techniques》
摘要： Tritium self-sustain and circulation is the core problem to use fusion energy peacefully. As the core component of the breeder in-pile irradiation test, the irradiation tritium production device provides irradiation space for breeders' tritium production and release. We take the Li4SiO4 as the research object and design the structure of the irradiation device. We complete the physical parameters computation, the irradiation device safety analysis and the flow field analysis of the breeder refueling, realizing the adjusting of the breeder irradiation temperature and the tritium release temperature window and making the control of gas operational parameters come true. The data could provide reference for breeders in-pile irradiation research.
分类： 生物学 >> 植物学 >> 植物学研究、实验与植物演化、发展 提交时间： 2016-05-04
摘要： Local haplotype patterns surrounding densely spaced DNA markers with significant trait associations can reveal information on selective sweeps and genome diversity associated with important crop traits. Relationships between haplotype and phenotype diversity, coupled with analysis of gene content in conserved haplotype blocks, can provide insight into coselection for nonrelated traits. We performed genome-wide analysis of haplotypes associated with the important physiological and agronomic traits leaf chlorophyll and seed glucosinolate content, respectively, in the major oilseed crop species Brassica napus. A locus on chromosome A01 showed opposite effects on leaf chlorophyll content and seed glucosinolate content, attributed to strong linkage disequilibrium (LD) between orthologues of the chlorophyll biosynthesis genes EARLY LIGHT-INDUCED PROTEIN and CHLOROPHYLL SYNTHASE, and the glucosinolate synthesis gene ATP SULFURYLASE 1. Another conserved haplotype block, on chromosome A02, contained a number of chlorophyll-related genes in LD with orthologues of the key glucosinolate biosynthesis genes METHYLTHIOALKYMALATE SYNTHASE-LIKE 1 and 3. Multigene haplogroups were found to have a significantly greater contribution to variation for chlorophyll content than haplotypes for any single gene, suggesting positive effects of additive locus accumulation. Detailed reanalysis of population substructure revealed a clade of ten related accessions exhibiting high leaf chlorophyll and low seed glucosinolate content. These accessions each carried one of the above-mentioned haplotypes from A01 or A02, generally in combination with further chlorophyll-associated haplotypes from chromosomes A05 and/or C05. The phenotypic rather than pleiotropic correlations between leaf chlorophyll content index and seed GSL suggest that LD may have led to inadvertent coselection for these two traits.
分类： 物理学 >> 核物理学 提交时间： 2025-06-18
摘要： This study investigates the effects of varying tritium breeding materials and their lithium enrichment rates on the Tritium Breeding Ratio (TBR) and Energy Multiplication Factor (M) within the tritium breeding zone of a fusion reactor. The magnetic fusion reactor model was developed based on the geometric and plasma parameters of the International Thermonuclear Experimental Reactor (ITER), ensuring a realistic representation of current fusion reactor designs.ITER-grade stainless steel (SS 316 LN-IG) was selected as the first wall material due to its excellent mechanical properties, high resistance to radiation damage, and compatibility with hightemperature environments. The coolant and tritium breeding materials considered in the blanket included natural lithium, lithium fluoride (LiF), lithium nitride (Li₃N), FLiBe (LiF-BeF₂), and FLiNaBe (LiF-NaF-BeF₂). These materials were chosen for their ability to facilitate tritium breeding while maintaining thermal and neutronic efficiency. Neutron transport calculations and geometric modeling were performed using the widely recognized 3D simulation tools MCNP5 and TopMC, which employ the continuous-energy Monte Carlo method. The simulations utilized built-in continuous-energy nuclear and atomic data libraries, along with the Evaluated Nuclear Data File (ENDF) system (ENDF/B-V and ENDF/B-VI), ensuring reliable and validated results.The results highlight the importance of material selection and enrichment optimization in achieving efficient tritium breeding and energy production. FLiBe, in particular, shows promise for future fusion reactor designs due to its superior performance in terms of TBR and M. These findings provide valuable insights for the development of sustainable and high-performance fusion reactors, contributing to the global pursuit of clean and virtually limitless energy.
分类： 生物学 >> 植物学 >> 植物细胞学与植物遗传学、植物形态学 提交时间： 2016-05-03
摘要： Biological assay has been based on analysis of all individuals collected from sample populations. Bulked sample analysis (BSA), which works with selected and pooled individuals, has been extensively used in gene mapping through bulked segregant analysis with biparental populations, mapping by sequencing with major gene mutants and pooled genomewide association study using extreme variants. Compared to conventional entire population analysis, BSA significantly reduces the scale and cost by simplifying the procedure. The bulks can be built by selection of extremes or representative samples from any populations and all types of segregants and variants that represent wide ranges of phenotypic variation for the target trait. Methods and procedures for sampling, bulking and multiplexing are described. The samples can be analysed using individual markers, microarrays and high-throughput sequencing at all levels of DNA, RNA and protein. The power of BSA is affected by population size, selection of extreme individuals, sequencing strategies, genetic architecture of the trait and marker density. BSA will facilitate plant breeding through development of diagnostic and constitutive markers, agronomic genomics, marker-assisted selection and selective phenotyping. Applications of BSA in genetics, genomics and crop improvement are discussed with their future perspectives.
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