Identification of ancient starch grains from the tribe Triticeae in the North China Plain

Both macrofossil and microfossil plant remains from the grass family (Poaceae) have been recovered from Neolithic and historic sites in China. Basing our work on the plant taxa that were previously recovered, we analyzed the economically significant genera for modern starch grain analysis with a focus on the important tribe Triticeae. Modern starch grains from the tribe Triticeae were compared with those from other grasses, and criteria for identification were determined. In total, 38 species within 28 genera, 13 tribes and 4 subfamilies were selected for analysis. Results demonstrate that starch grains from members of the tribe Triticeae are discernible from those of other tribes by their distinctive lenticular morphologies and surficial pressure craters. A dichotomous key covering 10 species within 7 genera of the Triticeae was created, thus allowing identification of members of the tribe to the level of genus. Application of the dichotomous key to the ancient starch assemblage recovered from lithic tools excavated from the early Neolithic site of Donghulin demonstrates that plants from the genera Hordeum and Agropyron were exploited alongside millets at this site.     

饭店应用供应链管理的特殊性与运作思路

饭店的供应链管理是饭店管理中非常重要但是还有待发展的课题。本文在现有的供应链及供应链管理理论基础上,对饭店所在的供应链及饭店在供应链中的必要性和特殊性进行了分析,提出了在饭店进行供应链管理的运作思路,力图使饭店能够建立优质的供应链体系,以增加饭店利润。     

城市环境供给的游憩者满意度及对重游意愿的影响——基于游客与居民差异的分析

在城市游憩中,到访游客和居民共享城市环境,形成了对城市环境供给的满意度评价。本文在回顾相关研究的基础上,利用武汉旅游市场调查数据进行量化分析,比较了内外部游客对环境供给因素满意度及其对重游意愿的影响。提出了游憩者体验城市环境供给的三个维度,即基础型、吸引型和增益型环境供给;并揭示了两个规律性现象:即到访游客对大部分环境供给的满意度高于居民的满意度;到访游客和居民的重游意愿均受到基础型环境供给因子满意度的影响。基于此,城市主管部门应更重视基础型环境供给的规划、建设与完善。     

重新解读旅游动力机制与管理供给

本文针对中国旅游发展在供给侧、需求侧以及两者交互下市场方面出现的问题及其折射出学术研究的人本性学理的缺陷,从新公共管理学学理出发,依据社会科学人本观“正负反馈机制”的方法论,结合人文地理学的空间结构价值理念,首次系统探讨旅游发展动力层次与层次替代范式及其层次动力间的交互机制。在此基础上又提出人本价值下旅游驱动力范式的相互交互反馈机制。包括：旅游需求侧的社会驱动力机制与流动交互转向规律、旅游管理侧的供给驱动机制与交互错位供给的失效规律、旅游消费文化市场与管理供给、社会需求交互的引领阻尼规律,以及旅游供给、需求与市场动力交互的反馈机制与范式。在上理念下论证了旅游发展是多元范式下的范式交替转移规律,并提出区域旅游管理的社会价值与空间体系耦合的旅游经营理念以及在此基础上的区域旅游公正机制管理、控制与规划路径。     

社会转型中的制度供给与需求--民初国会失败原因再探讨

民初建立的包括国会在内的一整套民主共和制度是一种供给主导型的制度变迁,这种变迁模式的成败取决于提供制度变迁的权力主体是否具有权威和理想。这一制度第一供给主体是南京临时政府,他们有理想但缺少权威,第二供给主体是北京政府,他们有权威但无理想。国会作为民主政治生活中限制个人独裁、维护公民权利的根本措施,就无法成功地在中国运行。制度需求的缺失也是造成国会失败的原因之一,但不是主要原因。     

Structure of grain boundaries in wet,synthetic polycrystalline,statically recrystallizing halite – evidence from cryo‐SEM observations

It is well known from nature and experiments that the presence of brine strongly affects the microstructural evolution and the mechanical and transport properties of halite. Existing interpretations of the grain boundary structure in deformed, wet, salt samples annealed statically at room temperature are based on indirect evidence from reflected light microscopy and conventional scanning electron microscopy. This paper presents direct observations of fluid‐filled grain boundaries using the cryogenic‐scanning electron microscope (cryo‐SEM) in which the grain boundary fluids were frozen before breaking the samples. The rapid cooling transforms the brine into two phases, i.e. ice and hydrohalite, which are easily recognized from characteristic segregation patterns. We studied samples of wet, synthetic, polycrystalline halite annealed under static conditions at room temperature. In coarse‐grained samples, fine‐scale segregation patterns were observed at the boundaries of the primary recrystallizing grains. These points indicate the existence of fluid films with a thickness in the range of 30 nm, but the finer scale structure of the fluid remains unknown. In fine‐grained samples, the distribution and reorganization of fluids with annealing time is recorded by the combination of contact healing and successive accumulation of fluids in triple junction tubes. The contact healing is attributed to the small initial grain size, such that the fluid film necks down by accumulating the fluids into previously existing triple junctions via neck growth. Electron backscatter diffraction measurements of both primary and secondary recrystallized grains indicate that they are euhedral, i.e. the grain growth morphology is controlled by the anisotropy of the grain boundary energy of the growing grain, which results in planar growth faces.     

Secular Regime Shifts,Global Warming and Sydney's Water Supply

Sydney's water crisis has been attributed to long-term drought, a population growing at >50 000 a year, the early impacts of global warming and the demands of a 4.2 million population leading a water-thirsty lifestyle. In this paper the drought is linked with a return to a drought-dominated flow regime in eastern New South Wales. This began in 1991 and is associated with a shift from flood to drought domination that occurs every 20 to 50 years. Its impacts will be further exaggerated by global warming. The reduction of runoff into Sydney's reservoirs is due primarily to regime shift, resulting in the diminution of inflows to about 25% of their levels in the 42 years before 1991. Possible ways of managing these dwindling water resources include building more reservoirs, exploiting largely unknown sources of groundwater, constructing a desalination plant, harvesting rainwater in the city, recycling used urban water and reducing individual water use. Despite arguments against the first three of these options, a desalination plant is currently under construction and investigations of deep groundwater proceed (shelved 18th June, 2008). Given that sources of water are distant and located in areas where rainfall reductions have been significant, greater efforts should be made to use water already in the city (rainfall and recycled water). Water restrictions and better domestic management of water are also areas where great savings can be and have been made.     

统购统销初期的粮食票证制度探析--以1953～1957年的河南为个案

1953～1957年的河南在统购统销初期实施粮食票证制度,经历了初创时期、基本成型时期、确立时期三个不同的发展阶段。粮食票证制度的形成,对于保证粮食统购统销政策的贯彻实施提供了有力的保障,并成为粮食统购统销制度的一个重要组成部分。     

The mechanism of fluid infiltration in peridotites at Almklovdalen, western Norway

A major Alpine‐type peridotite located at Almklovdalen in the Western Gneiss Region of Norway was infiltrated by aqueous fluids at several stages during late Caledonian uplift and retrogressive metamorphism. Following peak metamorphic conditions in the garnet–peridotite stability field, the peridotite experienced pervasive fluid infiltration and retrogression in the chlorite–peridotite stability field. Subsequently, the peridotite was infiltrated locally by nonreactive fluids along fracture networks forming pipe‐like structures, typically on the order of 10 m wide. Fluid migration away from the fractures into the initially impermeable peridotite matrix was facilitated by pervasive dilation of grain boundaries and the formation of intragranular hydrofractures. Microstructural observations of serpentine occupying the originally fluid‐filled inclusion space indicate that the pervasively infiltrating fluid was characterized by a high dihedral angle (θ > 60°) and ‘curled up’ into discontinuous channels and fluid inclusion arrays following the infiltration event. Re‐equilibration of the fluid phase topology took place by growth and dissolution processes driven by the excess surface energy represented by the ‘forcefully’ introduced external fluid. Pervasive fluid introduction into the peridotite reduced local effective stresses, increased the effective grain boundary diffusion rates and caused extensive recrystallization and some grain coarsening of the infiltrated volumes. Grain boundary migration associated with this recrystallization swept off abundant intragranular fluid inclusions in the original chlorite peridotite, leading to a significant colour change of the rock. This colour change defines a relatively sharp front typically located 1–20 cm away from the fractures where the nonreactive fluids originally entered the peridotite. Our observations demonstrate how crustal rocks may be pervasively infiltrated by fluids with high dihedral angles (θ > 60°) and emphasize the coupling between hydrofracturing and textural equilibration of the grain boundary networks and the fluid phase topology.     

周恩来与“文化大革命”时期的粮食问题

"文化大革命"使国民经济遭受了严重损失。周恩来殚精竭虑,采取种种措施,稳定粮食局势。他劝说红卫兵和造反派不能冲击农业生产,坚持抓南粮北调局面的改变,用"以出养进"的办法开展粮食外贸,努力解决"三个突破"中的粮食"窟窿"问题,认真贯彻藏粮于民的思想,常抓节约粮食。周恩来高度重视粮食问题的思想和为民谋利的风范至今仍有现实意义。