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991.
Cloning of the gene for spinocerebellar ataxia 2 reveals a locus with high sensitivity to expanded CAG/glutamine repeats 总被引:2,自引:0,他引:2
G Imbert F Saudou G Yvert D Devys Y Trottier JM Garnier C Weber JL Mandel G Cancel N Abbas A Dürr O Didierjean G Stevanin Y Agid A Brice 《Canadian Metallurgical Quarterly》1996,14(3):285-291
A 3-day monolithic polyacrylate adhesive dispersion type delivery system containing methadone was fabricated and in vitro permeation through hairless mouse and human cadaver skins was conducted. The effect of skin permeation enhancers was also investigated. Skin permeation rate across human cadaver skin was found to be lower than that of hairless mouse. Skin permeation profiles across both types of skins showed a membrane permeation controlled cumulative amount permeated (Q) versus time (t) relationship. Skin permeation rate was found to be dependent on both adhesive film thickness and loading dose of the drug in the matrix. Effective skin permeation rate across the hairless mouse skin was obtained from a patch with 1.5 mm thickness and 15% w/w loading dose. n-Decylmethyl sulfoxide and Azone were found to produce an effective skin permeation rate of methadone through human cadaver skin at a 5% w/w concentration. These initial studies demonstrated the feasibility of methadone administration through intact skin from a transdermal patch. 相似文献
992.
Although the theoretical framework of expert systems has been well established, the process of developing a non-trivial expert system is still considered a difficult task. The main reason for this is that the nature of expert systems is knowledge-intensive. Also, it is usually difficult for domain experts to explain or communicate their expertise to the system professionals. Many methodologies have been proposed to overcome this domain knowledge representation problem. Most of them require the assistance of an expert system shell (tool). However, with a purpose of helping the system development in mind, most of them were not satisfactory. This research takes the experience of implementing a course scheduling expert system, and suggests two analysis methods to describe the characteristics of course scheduling knowledge. It is shown that these methods provide assistance on clarifying the complicated scheduling problem. Another favorable advantage of this method is its capability helping the transferring of domain knowledge to rules in the knowledge base. 相似文献
993.
In this paper, we demonstrate how craft practice in contemporary jewellery opens up conceptions of ‘digital jewellery’ to
possibilities beyond merely embedding pre-existing behaviours of digital systems in objects, which follow shallow interpretations
of jewellery. We argue that a design approach that understands jewellery only in terms of location on the body is likely to
lead to a world of ‘gadgets’, rather than anything that deserves the moniker ‘jewellery’. In contrast, by adopting a craft
approach, we demonstrate that the space of digital jewellery can include objects where the digital functionality is integrated
as one facet of an object that can be personally meaningful for the holder or wearer. 相似文献
994.
Amorim Michel-Ange; Isableu Brice; Jarraya Mohamed 《Canadian Metallurgical Quarterly》2006,135(3):327
The cognitive advantage of imagined spatial transformations of the human body over that of more unfamiliar objects (e.g., Shepard-Metzler [S-M] cubes) is an issue for validating motor theories of visual perception. In 6 experiments, the authors show that providing S-M cubes with body characteristics (e.g., by adding a head to S-M cubes to evoke a posture) facilitates the mapping of the cognitive coordinate system of one's body onto the abstract shape. In turn, this spatial embodiment improves object shape matching. Thanks to the increased cohesiveness of human posture in people's body schema, imagined transformations of the body operate in a less piecemeal fashion as compared with objects (S-M cubes or swing-arm desk lamps) under a similar spatial configuration, provided that the pose can be embodied. If the pose cannot be emulated (covert imitation) by the sensorimotor system, the facilitation due to motoric embodiment will also be disrupted. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
According to the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) report in 1982, radiation from radon contributes about 50% of all natural radiation sources to the public. The situation is worse in Hong Kong where large area is granitic containing larger amount of uranium when compared to the global mean. Radon level can therefore be on the high side during tunneling especially where poor ventilation is envisaged. This article includes realistic field study of radon in tunnel under construction. A maximum concentration of over 30,000?Bq/m3 was recorded (1 Becquerels per cubic meter is equivalent to 0.027?pico?Curies/L). Radon concentration in tunnel environment is found to be related to groundwater ingress, ventilation provision and geology. A review of the current statutory control in Hong Kong is done as well as its comparison with other countries’ practices. In fact, the situation can be improved through education, adopting control legislation and more specifically, having a suggested radon management plan in every tunnel drilling project. 相似文献
996.
开关模式电源(SMPS)功率电感器的选择过程绝非是信手拈来那么简单,必须要对对实际电感器有充分的了解。SMPS的选用要求包括:大功率、小尺寸、高开关频率和高效率。此外,考虑到健康、环保方面的因素,很多用户还提出了降低电磁辐射(EMI)的要求。理想的电感器选择除了取决于对实际电感器(并不完善的)特性的了解之外,还需要对完善的电感器特性有一定的通晓。储能方面的考虑14种基本的SMPS设计大多依靠电感器来进行储能和EMI抑制(滤波)。控制电路负责对储存的能量进行调节,并通过将电感器与电源相连的方法来增加能量的存储。存储在一个电… 相似文献
997.
998.
Verbal information has long been assumed to be an indirect pathway to fear. Children (aged 6-8 or 12-13 years) were exposed to threat, positive, or no information about 3 novel animals to see the long-term impact on their fear cognitions and the immediate impact on avoidance behavior. Their directly (self-report) and indirectly (implicit association task) measured attitudes toward the animals changed congruent with the information provided, and the changes persisted up to 6 months later. Verbal threat information also induced behavioral avoidance of the animal. Younger children formed stronger animal- threat and animal-safe associations because of threat and positive verbal information than older children, but there were negligible age effects on self-reported fear beliefs and avoidance behaviors. These results support theories of fear acquisition that suppose that verbal information affects components of the fear emotion. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
A novel paradigm was developed to study the behavior of groups of networked people searching a problem space. The authors examined how different network structures affect the propagation of information in laboratory-created groups. Participants made numerical guesses and received scores that were also made available to their neighbors in the network. The networks were compared on speed of discovery and convergence on the optimal solution. One experiment showed that individuals within a group tend to converge on similar solutions even when there is an equally valid alternative solution. Two additional studies demonstrated that the optimal network structure depends on the problem space being explored, with networks that incorporate spatially based cliques having an advantage for problems that benefit from broad exploration, and networks with greater long-range connectivity having an advantage for problems requiring less exploration. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
E Wattel E Solary B Hecquet D Caillot N Ifrah A Brion B Mahé N Milpied M Janvier A Guerci H Rochant C Cordonnier F Dreyfus A Buzyn L Hoang-Ngoc AM Stoppa N Gratecos A Sadoun A Stamatoulas H Tilly P Brice F Maloisel B Lioure B Desablens P Fenaux 《Canadian Metallurgical Quarterly》1998,102(4):1015-1024
A method is developed which makes it possible to scan and reconstruct an object with cone beam x-rays in a spiral scan path with area detectors much shorter than the length of the object. The method is mathematically exact. If only a region of interest of the object is to be imaged, a top circle scan at the top level of the region of interest and a bottom circle scan at the bottom level of the region of interest are added. The height of the detector is required to cover only the distance between adjacent turns in the spiral projected at the detector. To reconstruct the object, the Radon transform for each plane intersecting the object is computed from the totality of the cone beam data. This is achieved by suitably combining the cone beam data taken at different source positions on the scan path; the angular range of the cone beam data required at each source position can be determined easily with a mask which is the spiral scan path projected on the detector from the current source position. The spiral scan algorithm has been successfully validated with simulated cone beam data. 相似文献