精细农业推进现代农业发展:机理分析和现实依据

精细农业是一种现代化农业理念,也是现代农业的重要板块和有效推手。新时期需要发挥精细农业的功能和作用,推动现代农业精细化发展,实现农业提质增效。精细农业是通过提高农业中生产投入的精细化程度、生产过程的精细化程度和农业产出的精细化程度来推进现代农业发展的。但是,中国农业发展过程中,依旧存在着农业生产要素扭曲错配、现代信息技术应用不足、农村新型经营主体发育不完善、资源环境发展不平衡、农业"三本齐升"现象突出和农产品供给失衡等问题,这些问题倒逼中国加快精细农业的发展。精细农业推进现代农业发展,需要建立精细化农产品基地,建立精细农业的生产体系、产业体系和经营体系,提高农业劳动力素质和培育"三农"工作队伍,加快科技兴农、质量兴农和绿色兴农步伐。     

Observational evidence for a possible new diffusion path

Transmission electron microscopy of experimentally deformed amphibolite suggests that submicroscopic intracrystalline tubes formed around linear defects may be a previously unrecognized kind of diffusion pathway. Deformed and compositionally altered plagioclase and amphibole crystals include moderate densities of linear defects that morphologically resemble unit dislocations but display unusual contrast. During prolonged electron irradiation, the core regions of the defects expand to well-defined tubes that are approximately 20 nanometers in diameter. Both observations suggest that the regions about the defect cores are glassy and were filled with silicate-water fluid during the experiments. Intracrystalline transport along these tubes would likely be several orders of magnitude faster than traditionally conceived processes of solid-state volume diffusion, grain-boundary solvent transfer, and ordinary pipe diffusion along dislocation cores.     

Genetic and fossil evidence for the origin of modern humans

The origin of living Homo sapiens has once again been the subject of much debate. Genetic data on present human population relationships and data from the Pleistocene fossil hominid record are used to compare two contrasting models for the origin of modern humans. Both genetics and paleontology support a recent African origin for modern humans rather than a long period of multiregional evolution accompanied by gene flow.     

Genetic evidence for transmembrane acetylation by lysosomes

Acetyl-CoA:alpha-glucosaminide N-acetyltransferase is a lysosomal-membrane enzyme deficient in a genetic disorder, Sanfilippo disease type C. The enzyme catalyzes the transfer of an acetyl group from cytoplasmic acetyl-coenzyme A (acetyl-CoA) to terminal alpha-glucosamine residues of heparan sulfate within the organelle. Previous kinetic experiments indicated that the enzyme carries out a transmembrane acetylation via a ping-pong mechanism; the reaction can therefore be dissected into two half reactions--acetylation of the enzyme, and transfer of the acetyl group to glucosamine. Cells derived from patients were found to differ in their ability to perform each half reaction. Five cell lines (derived from three families) were able to catalyze acetylation of the lysosomal membrane and to carry out acetyl-CoA/CoA exchange, whereas a sixth cell line was devoid of this activity.     

发展观光休闲农业 推进现代农业建设

本文论述了发展观光休闲农业的现实意义和龙岩市观光休闲农业的发展现状与存在问题,并就龙岩市今后发展对策提出若干建议。     

试析精细农业与计算机农业

我国农业正经历新的变革，向着现代化迈进，其核心就是以经济效益为中心、资源开发为基础、市场开拓为导向，实行农业产业化经营，发展农业和农村经济。 因此，为产供销、种养加、贸工农、农科教一体化经营服务的农业产前、产中、产后各个环节，应以发展农业和农村经济的主导产业和主导产品为目标。 当前，以计算机为核心的人工智能技术、网络技术、机器人技术、全球卫星定位系统（GPS）、3S应用技术、农业情报信息系统、农业远程教育、数字农业、农产品拍卖市场等，正影响和改变着农业和农村的面貌，并在农业生产、加工、包装、贮运、销…     

Genetic evidence for two species of elephant in Africa

Elephants from the tropical forests of Africa are morphologically distinct from savannah or bush elephants. Dart-biopsy samples from 195 free-ranging African elephants in 21 populations were examined for DNA sequence variation in four nuclear genes (1732 base pairs). Phylogenetic distinctions between African forest elephant and savannah elephant populations corresponded to 58% of the difference in the same genes between elephant genera Loxodonta (African) and Elephas (Asian). Large genetic distance, multiple genetically fixed nucleotide site differences, morphological and habitat distinctions, and extremely limited hybridization of gene flow between forest and savannah elephants support the recognition and conservation management of two African species: Loxodonta africana and Loxodonta cyclotis.     

Genetic evidence for an East Asian origin of domestic dogs

The origin of the domestic dog from wolves has been established, but the number of founding events, as well as where and when these occurred, is not known. To address these questions, we examined the mitochondrial DNA (mtDNA) sequence variation among 654 domestic dogs representing all major dog populations worldwide. Although our data indicate several maternal origins from wolf, >95% of all sequences belonged to three phylogenetic groups universally represented at similar frequencies, suggesting a common origin from a single gene pool for all dog populations. A larger genetic variation in East Asia than in other regions and the pattern of phylogeographic variation suggest an East Asian origin for the domestic dog, approximately 15,000 years ago.     

荷兰农业对上海农业发展的启示

通过荷兰和上海的农业经济特征对比,指出了上海与荷兰在农业发展上的差距,并通过分析荷兰农业的成功因素,提出了荷兰农业对上海农业发展的启示与可借鉴之处.     

Genetic evidence that protein synthesis is required for the circadia clock of neurospora

Small doses of cycloheximide given at intervals (pulses) cause phase shifts of the circadian clock of Neurospora. The effects of this drug on the clock are mediated through its inhibition of protein synthesis, since two cycloheximide-resistant mutants whose 80S ribosomes are resistant to cycloheximide showed no phase shift after exposure to the durg.     

广西农业发展值得研究的几个问题

针对广西农业发展的现实需要,探讨提出全面调查评估广西农业耕作制度;加强薯类作物研究与开发;发展多种高效农业耕作模式;研究探索蜜蜂养殖和发展油葵、油菜、山茶等油料作物,构建广西“蜂油产业”;重视占广西甘蔗种植面积60%以上的＂新台糖22号＂的持续利用等问题。     

Educational needs and perceptions of the sustainability of precision agriculture: survey evidence from Greece

Precision agriculture (PA) constitutes a dynamic production method which is gaining attention in several parts of the world. Its environmental and economic sustainability has been examined in terms of its ability to reduce the adverse effects of agrochemical use—by regulating their application to the levels needed at the land parcel level—and of its contribution to higher incomes and profitability. At the social level, PA has been linked to collective action although little insight is available regarding the role of various actors and education. This study tackles PA through an assessment of the attitudes of farmers towards the elements of its sustainability and of their educational needs. The analysis of survey data of a sample of young farmers in Greece showed that the majority of respondents were not familiar with PA. Significant differences were found between the attitudes of knowledgeable and non-knowledgeable farmers, the former demonstrating better acknowledgement of the environmental, economic and social sustainability of PA. Important educational needs were also detected, with group and individual methods being the most preferred ones for education and information campaigns. The results of the analysis could be of use for the design of Common Agricultural Policy Pillar II measures for the promotion of PA targeting to specific audiences and actors.     

按《合同法》要求规范“订单农业”的对策

对我国订单农业的内涵、主要形式及订单农业的现状进行了分析,尤其对订单农业中订单合同存在的问题,从《合同法》角度进行了探讨。提出了现阶段农产品购销合同存在缔约主体地位不对等;合同内容、形式不规范;合同内容不稳定,受市场影响大,以及合同在一定程度上受到行政干预等问题。提出按《合同法》要求规范“订单农业”的具体对策,即增强订单农业合同当事人的法律意识,贯彻诚实信用原则,保证农产品交易安全;提高农民组织化程度,改变合同缔约主体地位不对等的状况。按《合同法》要求规范农业订单的内容、形式及违约责任等条款,为解决农产品购销合同纠纷,保护订单农业合同当事人的合法权益提供法律保障。     

加大对农业和农民的保护力度--美国农业发展引发的思考

农业补贴是世界通行的做法。笔者通过对美国农业补贴政策的分析，认为入世后的中国农业政策必须加大对农业、农民的补贴支持力度，这不仅必要，而且非常紧迫。笔者提出了中国农业保护政策的基本原则以及具体操作建议，即：加大并稳定中央财政对农业、农民的扶持力度，逐步减免农业税费，减少国家对农产品流通环节的补贴，以粮食生产环节为补贴主体等四条建议。     

农业科学研究院所做好项目工作的几点实质性建议

伴随着我国科研单位科技体制改革的不断深入，科研单位的企业化转制正在逐步的推进，科研单位的运作将面临着市场化优胜劣汰的竞争环境，而做好科研项目工作是院所生存的重中之重，本论文结合西藏农业科研院所的实际情况，有针对性的提出项目工作当中的一些实质性的问题及其对做好项目工作的一些个人建议，以供参考。     

关于以信息推动农业发展的探索

以信息化推动农业的发展是社会经济发展的必然趋势,实现农业信息化是发展现代农业的重要内容,是推动现代农业进程的有效手段,是改变农业面貌主要途径.