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101.
Nagano Nozomi; Porter Craig T.; Thornton Janet M. 《Protein engineering, design & selection : PEDS》2001,14(11):845-855
There are currently at least nine distinct glycosidase sequencefamilies which are all known to adopt a TIM barrel fold [Henrissat,B.and Davies,G. (1997) Curr. Opin. Struct. Biol., 7, 637644].To explore the relationships between these enzymes and theirevolution, comprehensive sequence and structure comparisonswere performed, generating four distinct clusters. The firstcluster, S1, comprises the 相似文献
102.
Janet Soler 《Pedagogy, Culture & Society》1999,7(3):523-540
The late 1990s have seen a resurgence of the arguments for a skills-focused literacy instruction programme. This article explores the New Zealand-based public and professional debates surrounding the promotion of a technocratic approach to literacy instruction during the 1940s and 1950s, and the reoccurrence of the reading debate in late 1990s. In the early stages of both literacy crises, the professional competency of education officials and primary teachers was attacked by business interests and their political allies. The aftermath of the earlier crisis highlights the failure of this mechanistic and 'culture neutral' view of literacy instruction to cater for Maori children. The outcomes of the earlier debate signals a need avoid a similar conclusion to the current debate by adopting a broader approach to literacy instruction in the new millennium if language and literacy instruction programmes are to cater for complex cultural contexts, and the changing technological environments 相似文献
103.
Janet Coveney 《Urban Policy and Research》2013,31(4):208-216
Threats to national parks from development outside their boundaries are increasing especially on the urban fringe. This article examines the threats in Victoria and the USA. It looks at what has been done so far by town planners in Victoria to combat these threats. Various measures such as the use of siting and design guidelines, conservation covenants and agreements, zoning controls and the role of state and local government legislation are discussed. The article goes on to suggest what could be done. It discusses the importance of having buffer zones around parks in which the Department of Conservation and Natural Resources would become a statutory referral authority. The problems of defining the buffer zone and administering it are also discussed. The author calls for more co-operation between state and local government authorities to reduce these threats. How America handles these threats is also mentioned. 相似文献
104.
Michelle Gerritsen Julia T. Oxford Megan Frary Jonathan Henderson Janet M. Hampikian 《Materials science & engineering. C, Materials for biological applications》2008,28(3):341-346
Collagen is a vital material in the tissues of living organisms. Found almost everywhere in the human body, collagen is important in connective tissues, bone growth, and cartilage. Collagen XI makes up a very small portion of the cartilaginous tissue; however, it plays a key role in cartilaginous tissue. Collagen XI and two collagen XI isoforms, V1b and V2, are critical in the ossification process. The location of collagen XI, V1b, V2, and their specific functions in the ossification process within developing bovine cartilage are not well characterized. In this work, the location of collagens I, II, XI and two collagen XI isoforms, V1b and V2, present in developing bovine cartilage are investigated using the immuno-SEM technique. The results for the locations of collagen I and II indicate a high level of consistency with previous work, thus showing that the technique of immuno-SEM can be used with confidence to determine the location of various collagen types within cartilaginous and mineralized tissue. This work has shown that collagen XI is present in the lower hypertrophic region and also in a pericellular arrangement, within about two microns of cell walls, throughout the cartilaginous tissue. V1b is expressed in the articular surface, mineralized region, resting zone, and the distal edge of the diaphysis. The V2 isoform is most strongly expressed in areas of newly forming cartilage, and disappears with chondrocyte maturation. V2 is present in the distal edge of the epiphysis, as well as in mineralized tissue. Collagen XI and two of its isoforms, V1b and V2, are thought to play a critical role in the ossification process. However, this role is not well understood, and is still being characterized. The detection of collagen XI and two of its isoforms in the osteo-chondral junction as well as at a joint surface further point to collagen XI, V1b, and V2 playing a vital role in the ossification process, and warrants further research as to their specific function within the ossification process. 相似文献
105.
从代理、到自己投入半导体尖端制程设备研发,汉辰科技董事长黄民奇,日前在捐赠先进半导体制程设备予台湾国研院奈米组件实验室的仪式后,很多人都说,半导体尖端制程设备研发是精密机械工业,但他认为,应该称之为“制程工业”才对! 相似文献
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The interaction of CKDs with a given soil depends on the chemical and physical characteristics of the CKDs. Hence, the characterization of CKDs and their hydration products may lead to better understanding of their suitability as soil stabilizers. In the present article, four different CKD powders are characterized and their hydration products are evaluated. A detailed chemical (X-ray diffraction), thermogravimetric and morphological (scanning electron microscope) analyses of both the CKD powders and the hydrated CKD pastes are presented. In general, high free-lime content (~ 14–29%) CKDs, when reacted with water produced significant amounts of calcium hydroxide, ettringite and syngenite. These CKDs also developed higher unconfined compressive strength and higher temperature of hydration compared to CKDs with lower amounts of free-lime. An attempt was made to qualitatively correlate the performance of CKD pastes with the chemical and physical characteristics of the original CKD powders and to determine their potential suitability as soil stabilizers. To that effect a limited unconfined compressive strength testing of CKD-treated kaolinite clays was performed. The results of this study suggest that both the compressive strength and the temperature of hydration of the CKD paste can give early indications of the suitability of particular CKD for soil stabilization. 相似文献
110.
Performed a meta-analysis of 100 studies (published 1963–1988) of gender differences in mathematics performance. They yielded 254 independent effect sizes, representing the testing of 3,175,188 Ss. Averaged overall effect sizes based on samples of the general population indicated that females outperformed males by only a negligible amount. An examination of age trends indicated that girls showed a slight superiority in computation in elementary school and middle school. There were no gender differences in problem solving in elementary or middle school; differences favoring men emerged in high school and college. Gender differences were smallest and actually favored females in samples of the general population, grew larger with increasingly selective samples, and were largest for highly selected samples and samples of highly precocious persons. The magnitude of the gender difference has declined over the years. Gender differences in mathematics performance are small. Nonetheless, the lower performance of women in problem solving that is evident in high school requires attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献