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排序方式: 共有1462条查询结果,搜索用时 892 毫秒
91.
92.
Lunn KE Paulsen KD Roberts DW Kennedy FE Hartov A West JD 《IEEE transactions on medical imaging》2003,22(11):1358-1368
Brain shift during open cranial surgery presents a challenge for maintaining registration with image-guidance systems. Ultrasound (US) is a convenient intraoperative imaging modality that may be a useful tool in detecting tissue shift and updating preoperative images based on intraoperative measurements of brain deformation. We have quantitatively evaluated the ability of spatially tracked freehand US to detect displacement of implanted markers in a series of three in vivo porcine experiments, where both US and computed tomography (CT) image acquisitions were obtained before and after deforming the brain. Marker displacements ranged from 0.5 to 8.5 mm. Comparisons between CT and US measurements showed a mean target localization error of 1.5 mm, and a mean vector error for displacement of 1.1 mm. Mean error in the magnitude of displacement was 0.6 mm. For one of the animals studied, the US data was used in conjunction with a biomechanical model to nonrigidly re-register a baseline CT to the deformed brain. The mean error between the actual and deformed CT's was found to be on average 1.2 and 1.9 mm at the marker locations depending on the extent of the deformation induced. These findings indicate the potential accuracy in coregistered freehand US displacement tracking in brain tissue and suggest that the resulting information can be used to drive a modeling re-registration strategy to comparable levels of agreement. 相似文献
93.
Biesanz Jeremy C.; West Stephen G.; Millevoi Allison 《Canadian Metallurgical Quarterly》2007,92(1):119
Theory and research examining length of acquaintance and consensus among personality judgments have predominantly examined each dimension of personality separately. In L. J. Cronbach's (1955) terminology, this trait-centered approach combines consensus on elevation, differential elevation, and differential accuracy in personality judgments. The current article extends D. A. Kenny's (1991, 1994) weighted average model (WAM)--a theoretical model of the factors that influence agreement among personality judgments--to separate out two of Cronbach's components of consensus: stereotype accuracy and differential accuracy. Consistent with the predictions based on the WAM, as length of acquaintance increased, self-other agreement and consensus differential accuracy increased, stereotype accuracy decreased, and trait-level or raw profile correlations generally remained unchanged. Discussion focuses on the conditions under which a relationship between length of acquaintance and consensus and self-other agreement among personality evaluations emerges and how impressions change over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Tsviya Olender Marilyn Safran Ron Edgar Gil Stelzer Noam Nativ Naomi Rosen Ronit Shtrichman Yaron Mazor Michael D. West Ifat Keydar Noa Rappaport Frida Belinky David Warshawsky Doron Lancet 《Israel journal of chemistry》2013,53(3-4):185-198
A network of biological databases is reviewed, supplying a framework for studies of human genes and the association of their genomic variations with human phenotypes. The network is composed of GeneCards, the human gene compendium, which provides comprehensive information on all known and predicted human genes, along with its suite members GeneDecks and GeneLoc. Two databases are shown that address genes and variations focusing on olfactory reception (HORDE) and transduction (GOSdb). In the realm of disease scrutiny, we portray MalaCards, a novel comprehensive database of human diseases and their annotations. Also shown is GeneKid, a tool aimed at generating novel kidney disease biomarkers using systems biology, as well as Xome, a database for whole-exome next-generation DNA sequences for human diseases in the Israeli population. Finally, we show LifeMap Discovery, a database of embryonic development, stem cell research and regenerative medicine, which links to both GeneCards and MalaCards. 相似文献
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97.
An investigation of phosphate based ECMP electrolyte performance on feature scale planarization 总被引:1,自引:0,他引:1
Conventional copper chemical mechanical planarization (CMP) techniques are being pushed to their limits by increasing industrial
standards caused by device miniaturization and the use of new materials. There is a need to investigate alternative methods
of polishing to maintain and/or improve planarization standards while operating at low downforce. In this study, electrochemical
mechanical planarization (ECMP) is considered as an alternative and/or an extension to current CMP processes. ECMP is unique
due to the combination of an applied voltage to oxidize Cu and an abrasion from a polishing pad, which potentially allows
the system to achieve high levels of planarization through the use of an appropriately tailored electrolyte. An electrolyte
containing 1.0 M potassium phosphate salt concentration with a pH value of 2 and a benzotriazole (BTA) concentration of 0.001 M
was tested for its planarization capability on patterned Cu structures using a custom built ECMP tool. Feature sizes of the
Cu structures were varied from 1 to 6 μm. Similar planarization results were achieved using three pad types. All experiments
were performed at 0.5 V versus Ag/AgCl reference. The average step height reduction (SHR) was ~840 nm while the decrease in
the average metal thickness removed (λavg) was on the order of ~430 nm. Because features were approximately 50% of the substrate area, the total average metal thickness
removed was approximately half of the SHR for all three pad types. 相似文献
98.
This paper highlights the key issues which affected the design and implementation of water policy within the first phase of the Environmental Programme for the Danube River Basin. The programme represents one of several regional environmental initiatives in Eastern Europe which were designed to control pollution through the coordinated actions of national governments, international organizations, international financial institutions and non-governmental organizations.
The paper identifies three key controversial findings. Firstly, although the programme has been a valuable tool for the skills and technology transfer which are necessary to enable the Danube states to control water pollution, it has failed to generate the anticipated levels of capital investment or establish itself as a cornerstone of Danube basin management. Secondly, the policy process has been beset by political, economic, social and historical conflicts and power struggles between the participating parties. Thirdly, valuable lessons for the strategic and sustainable management of international river basins can be learned from the operational experiences of the Danube programme. 相似文献
The paper identifies three key controversial findings. Firstly, although the programme has been a valuable tool for the skills and technology transfer which are necessary to enable the Danube states to control water pollution, it has failed to generate the anticipated levels of capital investment or establish itself as a cornerstone of Danube basin management. Secondly, the policy process has been beset by political, economic, social and historical conflicts and power struggles between the participating parties. Thirdly, valuable lessons for the strategic and sustainable management of international river basins can be learned from the operational experiences of the Danube programme. 相似文献
99.
In this article we report that imitation and improvisation of tutor songs by eastern male cowbirds (Molothrus ater ater) differs when they are housed with conspecific females as opposed to nonconspecifics. When males, tutored with 12 different song types, were individually housed with females, they developed repertoires composed primarily of improvised and original song types, whereas the repertoires of males housed with canaries were composed entirely of copies of the tutor songs. Song preferences of the female companions for individual tutor songs were unaffected by social housing. The potency of the males' repertoires, as tested by playback to females, appeared to be related to the song responsiveness of their female companions. The results add further evidence that suggests that male cowbirds configure their song repertoire by attending to social signals from companions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
Malow Robert M.; West Jeffrey A.; Sutker Patricia B. 《Canadian Metallurgical Quarterly》1987,96(3):184
Relations between anxiety and pain were assessed in inpatient male drug abusers characterized by high, moderate, and low anxiety levels. A tonic pain stimulus was used for enhanced similarity to clinical pain, and sensory decision theory methodology was applied to measure discriminative and decisional aspects of pain response. Compared with minimally and moderately anxious subjects, highly anxious men demonstrated decreased pain response latencies, reduced abilities to discriminate noxious stimuli, and increased bias to report pain. These findings have relevance for understanding pain perception, self-perceived anxiety, and more general emotional distress in clinical samples. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献