基于时空感知能力的农业信息搜索技术研究

【目的】为具备时空感知能力的农业专业信息搜索引擎的研制提供关键技术与原型系统,并最终实现更高的查全率、查询效率和用户体验。【方法】以"农搜"为研究对象,通过对搜索引擎系统结构、关键技术和数据结构的研究与分析,并借鉴现有的中分分词和搜索技术、地名搜索技术和地名词典等关键技术,向"农搜"加入独立于农业主题搜索的位置索引和位置查询的方法以实现对位置(区域)的检索。【结果】应用此项技术形成了具备时空感知能力的农业信息搜索原型系统,经测试该原型系统能使位置搜索的查准率达到80%以上。【结论】基于时空感知能力的农业信息搜索技术的应用和推广必将能够提高农业信息系统的使用效率,进而取得较好的用户使用效果。     

Space perception in early infancy: perception within a common auditory-visual space

Infants as young as 30 days become visibly distressed upon observing their mothers speak to them while the mother's voice is displaced in space. Their ability to perceive this discrepancy indicates that infant perception occurs within a space that is common to the visual and auditory modes.     

Space perception in early infancy: perception within a common auditory-visual space?

Human infants aged I to 7 months were exposed to modifications of the normal spatial relationship between their mothers' face and voice. There was no evidence that such modifications were experienced by the infants as violations of a preexisting expectancy for face and voice to occupy the same spatial location.     

Global human capital: integrating education and population

Almost universally, women with higher levels of education have fewer children. Better education is associated with lower mortality, better health, and different migration patterns. Hence, the global population outlook depends greatly on further progress in education, particularly of young women. By 2050, the highest and lowest education scenarios--assuming identical education-specific fertility rates--result in world population sizes of 8.9 and 10.0 billion, respectively. Better education also matters for human development, including health, economic growth, and democracy. Existing methods of multi-state demography can quantitatively integrate education into standard demographic analysis, thus adding the "quality" dimension.     

基于"三网合一"的基层农户信息服务软件的研制

本软件综合运用各种最新的信息技术以及主动武网关技术,将无线通讯网、固定电话网和互联网络连接在一起,实现信息的无缝跨接,拓宽了互联网络上应用系统的服务范围.农业专家或农技推广员利用本软件可以更加方便、快捷地为基层农户提供信息服务,有效的解决了基层农户信息传递的"最后一公里问题".     

Cancer immunoediting: integrating immunity's roles in cancer suppression and promotion

Understanding how the immune system affects cancer development and progression has been one of the most challenging questions in immunology. Research over the past two decades has helped explain why the answer to this question has evaded us for so long. We now appreciate that the immune system plays a dual role in cancer: It can not only suppress tumor growth by destroying cancer cells or inhibiting their outgrowth but also promote tumor progression either by selecting for tumor cells that are more fit to survive in an immunocompetent host or by establishing conditions within the tumor microenvironment that facilitate tumor outgrowth. Here, we discuss a unifying conceptual framework called "cancer immunoediting," which integrates the immune system's dual host-protective and tumor-promoting roles.     

Cell migration: integrating signals from front to back

Cell migration is a highly integrated multistep process that orchestrates embryonic morphogenesis; contributes to tissue repair and regeneration; and drives disease progression in cancer, mental retardation, atherosclerosis, and arthritis. The migrating cell is highly polarized with complex regulatory pathways that spatially and temporally integrate its component processes. This review describes the mechanisms underlying the major steps of migration and the signaling pathways that regulate them, and outlines recent advances investigating the nature of polarity in migrating cells and the pathways that establish it.     

Visual motion perception: experimental modification

If a human observer fixates a moving spiral pattern for 15 minutes, a negative aftereffect of motion is perceived when he inspects a stationary spiral 20 hours later. The illusory motion is seen only when the stationary test stimulus falls upon the portion of the retina which had been stimulated by real motion. Thus previous stimulation can cause a relatively long-term modification of vision.     

Motion perception: a color-contingent aftereffect

When observers who watched repeated alternations of a red contracting spiral and green expanding spiral were later shown stationary spirals, red and a green the red stationary spiral appeared to be expanding and the green stationary spiral appeared to be contracting. These color-contingent motion after effects complement reports of motion-contingent color aftereffects and suggest that both may reflect adaptation of detectors specific to color and motion.     

植株间伤害信息的传递:信号分子及感受机制

植物在遭受到机械损伤或昆虫取食后释放出的伤诱导挥发物,除了具有防御功能外,还可作为伤害信息在植株间传递,引起群体诱导抗性的产生.文中就伤诱导挥发物在植株间传递伤害信息的存在证据、伤害信息分子的可能标准以及植物对伤害信息的感知进行了综述.     

ENSO as an integrating concept in earth science

The El Ni?o-Southern Oscillation (ENSO) cycle of alternating warm El Ni?o and cold La Ni?a events is the dominant year-to-year climate signal on Earth. ENSO originates in the tropical Pacific through interactions between the ocean and the atmosphere, but its environmental and socioeconomic impacts are felt worldwide. Spurred on by the powerful 1997-1998 El Ni?o, efforts to understand the causes and consequences of ENSO have greatly expanded in the past few years. These efforts reveal the breadth of ENSO's influence on the Earth system and the potential to exploit its predictability for societal benefit. However, many intertwined issues regarding ENSO dynamics, impacts, forecasting, and applications remain unresolved. Research to address these issues will not only lead to progress across a broad range of scientific disciplines but also provide an opportunity to educate the public and policy makers about the importance of climate variability and change in the modern world.     

Primary production of the biosphere: integrating terrestrial and oceanic components

Integrating conceptually similar models of the growth of marine and terrestrial primary producers yielded an estimated global net primary production (NPP) of 104.9 petagrams of carbon per year, with roughly equal contributions from land and oceans. Approaches based on satellite indices of absorbed solar radiation indicate marked heterogeneity in NPP for both land and oceans, reflecting the influence of physical and ecological processes. The spatial and temporal distributions of ocean NPP are consistent with primary limitation by light, nutrients, and temperature. On land, water limitation imposes additional constraints. On land and ocean, progressive changes in NPP can result in altered carbon storage, although contrasts in mechanisms of carbon storage and rates of organic matter turnover result in a range of relations between carbon storage and changes in NPP.     

Civic dietetics: opportunities for integrating civic agriculture concepts into dietetic practice

When Thomas Lyson developed the concept of Civic Agriculture, he provided a useful framework for considering a range of distinct but related professional areas. One such profession is dietetics. Registered dietitians work in a broad range of professional settings, including academic, clinical, administrative, hospitality, food service, and consulting. Dietetic practice has traditionally and primarily been informed by advances in understanding of the role nutrients and food play in enhancing health and reducing chronic disease risk. With support from the American Dietetic Association (ADA), the largest credentialing organization for nutrition practitioners, an increasing number of dietetic professionals consider food and agricultural sustainability issues relevant to their training and practice. Longstanding organizational structures, practices, and alliances characterizing the association, however, may limit the extent to which the organization and its members unify around a concept of civic dietetics. Recent developments within the ADA indicating an emergence of civic dietetics. This paper suggests ways the civic agriculture concept may be applied to dietetic practice, and how civic dietetics may help further civic agriculture and sustainable food systems.