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排序方式: 共有221条查询结果,搜索用时 15 毫秒
31.
G Stevanin P Giunti GD Belal A Dürr M Ruberg N Wood A Brice 《Canadian Metallurgical Quarterly》1998,7(11):1809-1813
Spinocerebellar ataxia 7 (SCA7) is the eighth neurodegenerative disorder caused by a translated CAG repeat expansion. Normal SCA7 alleles carry from four to 35 CAG repeats, whereas pathological alleles carry from 37 to approximately 200. Intermediate alleles (IAs), with 28-35 repeats in the SCA7 gene are exceedingly rare in the general population and are not associated with the SCA7 phenotype, although they have been found among relatives of four SCA7 families. In two of these families, IAs bearing 35 and 28 CAG repeats gave rise, during paternal transmission, to SCA7 expansions of 57 and 47 repeats, respectively, that were confirmed by haplotype reconstructions in one case and by inference in the other. Furthermore, the four haplotypes segregating with IAs were identical to the expanded alleles in each kindred, but differed among the families, indicating multiple origins of the SCA7 mutation in these families with different geographical origins. Our results provide the first evidence of de novo SCA7 expansions from IAs that are not associated with the phenotype but can expand to the pathological range during some paternal transmissions. IAs that segregate in unaffected branches of the pedigrees might, therefore, constitute a reservoir for future de novo mutations that occur in a recurrent but random manner. This would explain the persistence of the disease in spite of the great anticipation (approximately 20 years/generation) characteristic of SCA7. So far, de novo expansions among the disorders caused by polyglutamine repeats have only been demonstrated in Huntington's disease. 相似文献
32.
An important aspect of plant operation is preventive maintenance of electrical apparatus. Local thermal overloads or bad electrical connections often appear as localized hot spots in energized electrical equipment. A survey of the use of infrared detection systems for location of such hot spots is presented. A tutorial introduction to infrared detection and imaging systems is given with emphasis on the requirements imposed by this particular application. Following this, a survey of commercially available systems suitable for remote detection of hot spots is presented. Finally, the highlights of new developments in infrared technology are discussed. 相似文献
33.
JM. Dubois JB. Ulrich MA. Brice 《Bulletin of Engineering Geology and the Environment》1984,29(1):251-254
The extraction of aggregates in the alluvial Plain of Alsace has grown rapidly since 1962. The production of these aggregates, half of which are exported, has certainly had positive effects on the local economy, but the untidy sprawl of extraction sites had had a damaging impact on the local environment (effects on water table, rural landscape and land prices). To deal with this situation, the regional authorities have decided to define a regional policy on gravel pits, with three objectives: maximum economic return on deposits, protection of the environment and recovering of worked-out pits. Under Article 109-1 of the French Mining Code, the Region of Alsace has embarked on the operational phase of this new policy on gravel pits by commissioning studies of 7 “Zones.... Gravières” or “Coordinated Gravel Extraction and Site Revovering Zones” (ZERC). Within these zones, 16 potential gravel extraction areas have been defined. Detailed studies will make it possible to establish the economic, geological, geotechnical, hydrogeological and agricultural criteria which will determine the siting of future gravel pits to meet production requirements for the next 30 years. Apart from these studies, consultation between the industry, elected representatives and local government bodies is necessary in working out such a scheme, whose purpose is to ensure that gravel extraction can exist in harmony side by side with agriculture or any other industrial or leisure activity in the region. 相似文献
34.
G Stevanin AS Lebre C Mathieux G Cancel N Abbas O Didierjean A Dürr Y Trottier Y Agid A Brice 《Canadian Metallurgical Quarterly》1997,60(6):1548-1552
35.
36.
Eron Leonard D.; Huesmann L. Rowell; Brice Patrick; Fischer Paulette; Mermelstein Rebecca 《Canadian Metallurgical Quarterly》1983,19(1):71
Conducted a 3-yr longitudinal study with 2 large samples of elementary school youngsters overlapping in 1 grade (N?=?672, 607, and 505 for each successive year). It was thus possible to trace developmental trends from Grades 1 to 5 on the following variables: aggression, frequency of TV viewing, extent of violence viewed on TV, judged realism of TV programs, and preference for masculine, feminine, or neutral activities. Data support the theory that there is a sensitive period during which the effect of TV can be especially influential on children's behavior. Further, since the correlation between violence viewing and aggression tends to increase until age 10–21 yrs, a cumulative effect beyond the sensitive period is suggested. (11 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
The origin of domain coercive force in thin nickel-iron films is of considerable scientific and technological interest. Three principal causes of domain coercive force have been suggested. These are surface roughness, inclusions, and the presence of magnetisation ripple in the films. The current theories of these contributions are outlined, and the results obtained experimentally are compared with those expected theoretically. On the basis of this comparison, it appears that all three contributions can be important. However, it is not clear how the components due to the various causes should be combined. 相似文献
38.
Camden Debruler Wenda Wu Kevin Cox Brice Vanness T. Leo Liu 《Advanced functional materials》2020,30(24)
Here, a pH neutral aqueous organic redox flow battery (AORFB) consisting of three electrolytes channels (i.e., an anolyte channel, a catholyte channel, and a central salt water channel) to achieve integrated energy storage and desalination is reported. Employing a low cost, chemically stable methyl viologen (MV) anolyte, and sodium ferrocyanide catholyte, this desalination AORFB is capable of desalinating simulated seawater (0.56 m NaCl) down to 0.023 m salt concentration at an energy cost of 2.4 W h L?1 of fresh water—competitive with current reverse osmosis technologies. Simultaneously, the cell delivers stored energy at 79.7% efficiency with a cell voltage of 0.85 V. Furthermore, the cell is also capable of higher current operation up to 15 mA cm?2, providing 4.55 mL of fresh water per hour. Combining energy storage and water desalination into such a bifunctional device offers the opportunity to address two growing global issues from one hardware installation. 相似文献
39.
The sociodemographic diversity of residential customers can affect the level of financial risk that an electricity provider experiences in the retail market. To demonstrate the relationship between sociodemographic diversity and financial risk, electricity consumption data drawn from the United Kingdom Power Networks ‘Low Carbon London’ project was analyzed to explore the relationship between sociodemographic diversity and financial risk experienced by electricity retailers. The results show that when increasing the sociodemographic diversity amongst a group of residential customers the effect on financial risk depends on the electricity consumption patterns of individual customers and the relationship of consumption patterns between residential customers. Increasing sociodemographic diversity amongst residential customers with very distinct energy consumption patterns can decrease the overall financial risk associated with the aggregated revenue received from these customers. However, the results showed that adding customers to a customer base without consideration for their sociodemographic background can cause the overall financial risk associated with the aggregated revenue received to change erratically. Whilst previous studies have considered customer diversity and its influence on peak electricity demand, this research advances the state-of-the-art by showing the importance of customer diversity to the financial quantity risk experienced by electricity retailers. This finding has serious implications for electricity providers seeking to mitigate financial risk in the retail electricity market. 相似文献
40.
Brice K. Grunert Shelby L. Brunner Sajad A. Hamidi Hector R. Bravo J. Val Klump 《Journal of Great Lakes research》2018,44(5):851-863
We present water column thermal structure for two climatically different years: 2012, which experienced abnormally warm spring and summer air temperatures preceded by a relatively low ice winter and 2013, which experienced cooler than average spring and average summer air temperatures and preceded by average ice conditions. Mean bottom water temperatures for the season and during cold water intrusions were significantly warmer in 2012 than 2013 leading to a significantly reduced stratified season in 2012. Cold water intrusions were driven into southern Green Bay by southerly winds while intrusions were terminated when winds switched to persistent northerly winds. 2012 observed a significant increase in northerly winds relative to 2013, decreasing cold water intrusion presence and duration but winds did not fully explain the difference in thermal conditions for southern Green Bay. These cold bottom waters drive stratification in polymictic southern Green Bay while dimictic waters were found to have significantly warmer bottom temperatures during 2012 and a deeper mixed layer. Our observations suggest that relatively shallow (<20?m), seasonally stratified systems may not increase in stratification strength and duration under a warming climate; rather, changing wind climatology and surface heat flux can inform the degree to which the mixing regime can be expected to change and impact stratification and thermal structure of coastal systems. We discuss the biogeochemical implications of different thermal regimes, particularly within the context of multiple drivers of physical water column structure in eutrophic, stratified coastal systems. 相似文献