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Berriman AC  Hinde DJ  Dasgupta M  Morton CR  Butt RD  Newton JO 《Nature》2001,413(6852):144-147
Unstable heavy atomic nuclei not found in nature can be created by fusing two stable nuclei, in a process analogous to colliding charged droplets of liquid. Recently, the formation of a handful of super-heavy nuclei with atomic numbers 114 (ref. 1) and 116 (ref. 2) has been achieved by fusion of heavy nuclei. The electrostatic energy of such systems is very large (which is the reason super-heavy nuclei are unstable), so although the two nuclei may initially be captured by the nuclear potential, rather than fusing, they almost always separate after transfer of mass to the lighter nucleus. This process, called quasi-fission, can inhibit fusion by many orders of magnitude. Understanding this inhibition may hold the key to forming more super-heavy elements. Theoretically, inhibition is predicted (ref. 5 and references therein) when the product Z1Z2 of the charges of the projectile and target nuclei is larger than about 1,600. Here we report measurements of three fusion reactions with Z1Z2 around half this value, each forming 216 88Ra. We find convincing model-independent evidence both of inhibition of fusion, and of the presence of quasi-fission. These results defy interpretation within the standard picture of nuclear fusion and fission.  相似文献   
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Reiner DJ  Newton EM  Tian H  Thomas JH 《Nature》1999,402(6758):199-203
Calcium/calmodulin-dependent serine/threonine kinase type II (CaMKII) is one of the most abundant proteins in the mammalian brain, where it is thought to regulate synaptic plasticity and other processes. Activation of the multisubunit kinase by calcium is effectively cooperative and can persist long after transient calcium rises. Despite extensive biochemical characterization of CaMKII and identification of numerous in vitro kinase targets, little is known about its function in vivo. Here we report that unc-43 encodes the only Caenorhabditis elegans CaMKII. A gain-of-function unc-43 mutation reduces locomotory activity, alters excitation of three muscle types and lengthens the period of the motor output of a behavioural clock. Null unc-43 mutations cause phenotypes generally opposite to those of the gain-of-function mutation. Mutations in the unc-103 potassium channel gene suppress a gain-of-function phenotype of unc-43 in one tissue without affecting other tissues; thus, UNC-103 may be a tissue-specific target of CaMKII in vivo.  相似文献   
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Due to different cultural and historical background, the technology in Western and Eastern pattern design is inherently different. Along with the development of technology, garment pattern design technique is making progress towards high effectiveness and accuracy. Many researchers proposed different alternative methodologies to improve the current pattern making processes. This article examines the development of Western and Eastern garment pattern design technique. The main objective of this article is to provide a thorough review and hence a better understanding to those researchers who made contribution on developing pattern design technique and continue their work in the future.  相似文献   
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Crop yields are significantly reduced by aluminum toxicity on highly acidic soils, which comprise up to 50% of the world's arable land. Candidate aluminum tolerance proteins include organic acid efflux transporters, with the organic acids forming non-toxic complexes with rhizosphere aluminum. In this study, we used positional cloning to identify the gene encoding a member of the multidrug and toxic compound extrusion (MATE) family, an aluminum-activated citrate transporter, as responsible for the major sorghum (Sorghum bicolor) aluminum tolerance locus, Alt(SB). Polymorphisms in regulatory regions of Alt(SB) are likely to contribute to large allelic effects, acting to increase Alt(SB) expression in the root apex of tolerant genotypes. Furthermore, aluminum-inducible Alt(SB) expression is associated with induction of aluminum tolerance via enhanced root citrate exudation. These findings will allow us to identify superior Alt(SB) haplotypes that can be incorporated via molecular breeding and biotechnology into acid soil breeding programs, thus helping to increase crop yields in developing countries where acidic soils predominate.  相似文献   
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Study on the Relation between Garment Style and Ease Distribution   总被引:6,自引:0,他引:6  
IntroductionGarment pattern design is a 3 D to 2 D surfacemapping process. Traditionally, thegarmentpattern designcan be classified as “Drafting Method” and “DrapingMethod”.“Drafting”is a direct drawing of the garmentpattern using known body measurements from themannequin. Since this method does not requiremanipulation in the 3 D space, it is called“flat patterntechnique”. All flatpattern design masters approximate thegarment pattern using …  相似文献   
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Biochar trials aim to enrich soil for smallholders   总被引:2,自引:0,他引:2  
Woods WI  Falcão NP  Teixeira WG 《Nature》2006,443(7108):144
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