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91.
Pollmann Stefan; Maertens Marianne; von Cramon D. Yves; Lepsien Joeran; Hugdahl Kenneth 《Canadian Metallurgical Quarterly》2002,16(1):56
The authors found splenial lesions to be associated with left ear suppression in dichotic listening of consonant-vowel syllables. This was found in both a rapid presentation dichotic monitoring task and a standard dichotic listening task, ruling out attentional limitations in the processing of high stimulus loads as a confounding factor. Moreover, directed attention to the left ear did not improve left ear target detection in the patients, independent of callosal lesion location. The authors' data may indicate that auditory callosal fibers pass through the splenium more posterior than previously thought. However, further studies should investigate whether callosal fibers between primary and secondary auditory cortices, or between higher level multimodal cortices, are vital for the detection of left ear targets in dichotic listening. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
Aimed to (1) chart late-adolescent individuation from freshman to junior year in college, (2) further examine previously reported sex differences in separation–individuation and college adjustment, and (3) assess the within-year and across-year association between individuation and adjustment. As part of an ongoing longitudinal project, 130 students completed measures of separation–individuation and college adjustment early in their freshman year (D. K. Lapsely et al, 1989). In the present follow-up study, 81 of those original Ss completed measures in their junior year. The results indicated significant increases in individuation from parents over time along most but not all dimensions of individuation for both men and women. Gender specific patterns of individuation/adjustment emerged in freshman and junior year. In general, independence from parents in freshman year did not predict junior year college adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Kenneth Srensen Gerrit K. Janssens 《Quality and Reliability Engineering International》2004,20(4):343-362
A production line is studied with several machines in series. The machines are separated with finite buffers. They can break down and have to be repaired. Production is assumed to be continuous, i.e. no individual products can be identified. Analytical models for the performance evaluation of such a system are scarce. Analytical results for the throughput can be obtained only under very restrictive assumptions. The performance study of longer transfer lines requires either approximation or simulation. A Petri net model is developed for an n‐machine ‐buffer system. The rules to design the Petri net transitions are given. The automatic generation of a discrete‐event simulation model from the Petri net model is explained. Finally, some potential applications of the Petri net are illustrated. These applications include the simulation of transfer lines with complex stochastic behaviour, the optimization of buffer size and allocation and the evaluation of approximation models for long transfer lines. Using the simulation model described in this paper, quality and reliability engineers can simulate the performance of a given continuous flow transfer line and evaluate the effect of performance‐increasing measures such as the insertion of extra buffer space or the use of more reliable machines. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
94.
Parambath Anilkumar Li Cao Jing‐Jiang Yu Kenneth N. Tackett II Ping Wang Mohammed J. Meziani Ya‐Ping Sun 《Small (Weinheim an der Bergstrasse, Germany)》2013,9(4):545-551
Carbon dots (surface‐passivated small carbon nanoparticles) are crosslinked to result in fluorescence probes containing one or multiple dots. For the single‐dot probes, the crosslinking further stabilizes the dot structure, while for those packed with multiple dots, the individual probe imaging results demonstrate that the fluorescence properties are additive, with more dots for higher emission intensities in a proportional fashion, thus enabling the preparation of ultra‐bright fluorescence probes. 相似文献
95.
Sol Efroni Daoud Meerzaman Carl F. Schaefer Sharon Greenblum Myung Soo&#x;Lyu Ying Hu Constance Cultraro Eran Meshorer Kenneth H. Buetow 《IET systems biology》2013,7(6):243
The development and progression of cancer is associated with disruption of biological networks. Historically studies have identified sets of signature genes involved in events ultimately leading to the development of cancer. Identification of such sets does not indicate which biologic processes are oncogenic drivers and makes it difficult to identify key networks to target for interventions. Using a comprehensive, integrated computational approach, the authors identify the sonic hedgehog (SHH) pathway as the gene network that most significantly distinguishes tumour and tumour‐adjacent samples in human hepatocellular carcinoma (HCC). The analysis reveals that the SHH pathway is commonly activated in the tumour samples and its activity most significantly differentiates tumour from the non‐tumour samples. The authors experimentally validate these in silico findings in the same biologic material using Western blot analysis. This analysis reveals that the expression levels of SHH, phosphorylated cyclin B1, and CDK7 levels are much higher in most tumour tissues as compared to normal tissue. It is also shown that siRNA‐mediated silencing of SHH gene expression resulted in a significant reduction of cell proliferation in a liver cancer cell line, SNU449 indicating that SHH plays a major role in promoting cell proliferation in liver cancer. The SHH pathway is a key network underpinning HCC aetiology which may guide the development of interventions for this most common form of human liver cancer.Inspec keywords: bioinformatics, cancer, cellular biophysics, genetics, liver, molecular biophysics, RNA, systems analysis, tumoursOther keywords: biomedical informatics, human liver cancer, network underpinning HCC aetiology, liver cancer cell line, cell proliferation, SHH gene expression, siRNA‐mediated silencing, CDK7 levels, phosphorylated cyclin B1, Western blot analysis, in silico findings, SHH pathway, human hepatocellular carcinoma, tumour‐adjacent samples, gene network, integrated computational approach, oncogenic drivers, biologic processes, cancer development, biological networks, cancer progression, oncogenic target, primary biomarker, sonic hedgehog pathway, pathway interactions, systems analysis 相似文献
96.
97.
Fredrik Larsson Kenneth Runesson Fang Su 《International journal for numerical methods in engineering》2010,81(13):1659-1686
A framework for variationally consistent homogenization, combined with a generalized macro‐homogeneity condition, is exploited for the analysis of non‐linear transient heat conduction. Within this framework the classical approach of (model‐based) first‐order homogenization for stationary problems is extended to transient problems. Homogenization is then carried out in the spatial domain on representative volume elements (RVE), which are (in practice) introduced in quadrature points in standard fashion. Along with the classical averages, a higher order conservation quantity is obtained. An iterative FE2‐algorithm is devised for the case of non‐linear diffusion and storage coefficients, and it is applied to transient heat conduction in a strongly heterogeneous particle composite. Parametric studies are carried out, in particular with respect to the influence of the ‘internal length’ associated with the second‐order conservation quantity. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
98.
99.
Linda is a co-ordination language designed to support process creation and interprocess communication within conventional computational languages. Although the Linda paradigm touts architectural and language independence, it often suffers performance penalties, particularly on local area network platforms. Instructional footprinting is an optimization technique with the primary goal of enhancing the execution speed of Linda programs. The two main aspects of instructional footprinting are instructional decomposition and code motion. The paper addresses the semantic issues encountered when the Linda primitives, IN and RD, are decomposed and moved past other Linda operations. Formal semantics are given as well as results showing significant speed-up (as high as 100%) when instructional footprinting is used. 相似文献
100.
Ivask A Suarez E Patel T Boren D Ji Z Holden P Telesca D Damoiseaux R Bradley KA Godwin H 《Environmental science & technology》2012,46(4):2398-2405
By exploiting a genome-wide collection of bacterial single-gene deletion mutants, we have studied the toxicological pathways of a 60-nm cationic (amino-functionalized) polystyrene nanomaterial (PS-NH(2)) in bacterial cells. The IC(50) of commercially available 60 nm PS-NH(2) was determined to be 158 μg/mL, the IC(5) is 108 μg/mL, and the IC(90) is 190 μg/mL for the parent E. coli strain of the gene deletion library. Over 4000 single nonessential gene deletion mutants of Escherichia coli were screened for the growth phenotype of each strain in the presence and absence of PS-NH(2). This revealed that genes clusters in the lipopolysaccharide biosynthetic pathway, outer membrane transport channels, ubiquinone biosynthetic pathways, flagellar movement, and DNA repair systems are all important to how this organism responds to cationic nanomaterials. These results, coupled with those from confirmatory assays described herein, suggest that the primary mechanisms of toxicity of the 60-nm PS-NH(2) nanomaterial in E. coli are destabilization of the outer membrane and production of reactive oxygen species. The methodology reported herein should prove generally useful for identifying pathways that are involved in how cells respond to a broad range of nanomaterials and for determining the mechanisms of cellular toxicity of different types of nanomaterials. 相似文献