Diethylstilbestrol induces neoplastic transformation without measurable gene mutation at two loci

The frequency with which diethylstilbestrol induces neoplastic transformation and somatic mutation was measured concomitantly in Syrian hamster embryo cells. While diethylstilbestrol was as active as benzo[a]pyrene in inducing transformation, it failed to induce mutations at two conventionally studied loci. These results suggest that diethylstilbestrol may transform cells in the absence of gene mutations.     

黄带虎天牛的生物学特性

黄带虎天牛（Ｃａｌｌｏｉｄｅｓｍａｇｎｉｆｉｃｕｓ（Ｐｉｃ）是危害花椒树的主要钻蛀性害虫。幼虫蛀食１０ａ生左右大龄树的主干和侧枝，该虫１ａ发生１代，以３，４龄幼虫的花椒树皮下越冬，成虫羽化高峰在６月下旬。本文较详细的记述了这种害虫的形态、生活史、寄主、习性及防治方法。     

Evidence for large decadal variability in the tropical mean radiative energy budget

It is widely assumed that variations in Earth's radiative energy budget at large time and space scales are small. We present new evidence from a compilation of over two decades of accurate satellite data that the top-of-atmosphere (TOA) tropical radiative energy budget is much more dynamic and variable than previously thought. Results indicate that the radiation budget changes are caused by changes in tropical mean cloudiness. The results of several current climate model simulations fail to predict this large observed variation in tropical energy budget. The missing variability in the models highlights the critical need to improve cloud modeling in the tropics so that prediction of tropical climate on interannual and decadal time scales can be improved.     

芒果的成熟与腐烂对介电特性的影响

为了探索芒果的成熟与腐烂对介电特性的影响,利用介电特性无损检测的原理,设计了无损检测系统,测试了芒果存贮过程中的介电特性,包括串联等效电容、损耗因素、电感,并联等效电容、损耗因素、电感和阻抗.测试频率为100Hz,120Hz,1kHz,10kHz.结果表明,在芒果存贮的第6～8天(即芒果普遍开始腐烂时),等效电容达到最大值,损耗因素、等效电感、阻抗达到一个最低值;用100 Hz频率来测试芒果的介电特性获得的综合测试效果好.     

Place,identity and immigrant communities: The organisation of the Yulan Festival in post‐war Hong Kong

Abstract: In the process of migration, some traditions persist while others do not. The Yulan Festival, also known as the Ghost Festival, continues to be observed by different subethnic Chinese migrant groups in Hong Kong for a variety of reasons. Although the festival organisation accentuates subethnic distinctions, paradoxically it also enables different groups to integrate into the larger community. The activities articulate various meanings of ‘place’– as ‘ancestral place’ on the mainland where
the rituals are believed to originate, as the specific locality/neighbourhood in Hong Kong where the festival is held, and Hong Kong as a whole. This article, based on interviews with Chiu Chow and Hoklo participants, shows how they think of the different meanings of ‘place’, which in turn reflects the way they make sense of the process of migration.     

A

A solid state, electronically addressable, bistable [2]catenane-based molecular switching device was fabricated from a single monolayer of the [2]catenane, anchored with phospholipid counterions, and sandwiched between an n-type polycrystalline silicon bottom electrode and a metallic top electrode. The device exhibits hysteretic (bistable) current/voltage characteristics. The switch is opened at +2 volts, closed at -2 volts, and read at approximately 0.1 volt and may be recycled many times under ambient conditions. A mechanochemical mechanism for the action of the switch is presented and shown to be consistent with temperature-dependent measurements of the device operation.     

Arginylation of beta-actin regulates actin cytoskeleton and cell motility

Posttranslational arginylation is critical for mouse embryogenesis, cardiovascular development, and angiogenesis, but its molecular effects and the identity of proteins arginylated in vivo are unknown. We found that beta-actin was arginylated in vivo to regulate actin filament properties, beta-actin localization, and lamella formation in motile cells. Arginylation of beta-actin apparently represents a critical step in the actin N-terminal processing needed for actin functioning in vivo. Thus, posttranslational arginylation of a single protein target can regulate its intracellular function, inducing global changes on the cellular level, and may contribute to cardiovascular development and angiogenesis.     

毛白杨根系分布的研究

对沙地上不同年龄毛白杨人工林的根系，从形态、数量和分布密度３个方面进行了调查研究。结果表明，其根系为水平斜生复合根型，１４ａ生林木根系的分布深度可达４．５ｍ，水平根幅达８ｍ左右。以重量划分７，９，１４ａ生林分的根系，分别集中在０￣６０ｃｍ、０￣１００ｃｍ和０￣１００ｃｍ土层内，占根系总重的８６％以上，树木周围２．０ｍ范围内根系的重量占总根量的８０％以上。以根系长度衡量，整个林地内根系分布较均匀，０     

The oceanic sink for anthropogenic CO2

Using inorganic carbon measurements from an international survey effort in the 1990s and a tracer-based separation technique, we estimate a global oceanic anthropogenic carbon dioxide (CO2) sink for the period from 1800 to 1994 of 118 +/- 19 petagrams of carbon. The oceanic sink accounts for approximately 48% of the total fossil-fuel and cement-manufacturing emissions, implying that the terrestrial biosphere was a net source of CO2 to the atmosphere of about 39 +/- 28 petagrams of carbon for this period. The current fraction of total anthropogenic CO2 emissions stored in the ocean appears to be about one-third of the long-term potential.     

Comparative study of cellulase treatment on low stress mechanical properties of cotton denim fabric made by torque-free ring spun yarn

Cellulase is useful for bio-polishing cotton fabrics which enhances their aesthetic performance instead of stonewashing process. Torque-free ring spun process is a widely used technique to produce newly low-twist and balanced torque yarns with soft hand. In this paper, denim fabrics woven with torque-free ring spun yarn and conventional ring spun yarn respectively were treated with cellulase under the same condition and their fabric handle, expressed as low stress mechanical properties, such as tensile strength, bending, shearing, compression and surface performance were investigated by Kawabata Evaluation System for Fabric (KES-F). After cellulase treatment, both denim fabrics revealed better flexibility, elasticity recovery, raised shearing stiffness, fluffier and improved smoothness. While torque-free ring spun yarn made denim fabric showed a better fabric handle than conventional ring spun yarn made denim fabric.