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991.
Yasushi Ito P. Corey Shum Alan M. Shih Bharat K. Soni Kazuhiro Nakahashi 《International journal for numerical methods in engineering》2006,65(6):943-973
In this paper, we propose efficient and robust unstructured mesh generation methods based on computed tomography (CT) and magnetic resonance imaging (MRI) data, in order to obtain a patient‐specific geometry for high‐fidelity numerical simulations. Surface extraction from medical images is carried out mainly using open source libraries, including the Insight Segmentation and Registration Toolkit and the Visualization Toolkit, into the form of facet surface representation. To create high‐quality surface meshes, we propose two approaches. One is a direct advancing front method, and the other is a modified decimation method. The former emphasizes the controllability of local mesh density, and the latter enables semi‐automated mesh generation from low‐quality discrete surfaces. An advancing‐front‐based volume meshing method is employed. Our approaches are demonstrated with high‐fidelity tetrahedral meshes around medical geometries extracted from CT/MRI data. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
992.
Small-format aerial photography (SFAP) is a low-cost solution for bridge-surface imaging and is proposed as a remote bridge-inspection technique to supplement current bridge visual inspection. Providing top-down views, photos taken from airplanes flying at 305?m (1,000?ft) allow for the visualization of subinch (i.e., large) cracks and joint openings on bridge decks or highway pavements. An onboard global positioning system can help geo-reference images collected and allow automated damage detection. However, the site lighting, surrounding tree shades, and highway surface reflectivity may affect the quality of the images. Several examples of bridge evaluation using SFAP are presented to demonstrate the capability of remote sensing as an effective tool for bridge-construction monitoring and condition assessment. A deck condition rating technique for large crack detection is proposed to quantify the condition of the existing bridge decks. 相似文献
993.
Corey T. Putkunz Jesse N. Clark David J. Vine Garth J. Williams Eugeniu Balaur Guido A. Cadenazzi Evan K. Curwood Clare A. Henderson Robert E. Scholten Russell J. StewartIan McNulty Keith A. Nugent Andrew G. Peele 《Ultramicroscopy》2011,111(8):1184-1188
This paper demonstrates the application of the high sensitivity, low radiation dose imaging method recently presented as phase diverse coherent diffraction imaging, to the study of biological and other weakly scattering samples. The method is applied, using X-ray illumination, to quantitative imaging of the granular precursors of underwater adhesive produced by the marine sandcastle worm, Phragmatopoma californica. We are able to observe the internal structure of the adhesive precursors in a number of states. 相似文献
994.
995.
An Sangmin Sung Baekman Noh Haneol Stambaugh Corey Kwon Soyoung Lee Kunyoung Kim Bongsu Kim Qhwan Jhe Wonho 《纳微快报(英文)》2014,6(1):70-79
Nano-Micro Letters - In this work, we introduce position-resolved surface characterization and nanofabrication using an optical microscope (OM) combined with a nanopipette-based quartz tuning fork... 相似文献
996.
Mice lacking Itk, a T-cell-specific protein tyrosine kinase, have reduced numbers of T cells and reduced responses to allogeneic major histocompatibility molecules. This study analyzed antiviral immune responses in mice deficient for Itk. Primary cytotoxic T-lymphocyte (CTL) responses were analyzed after infection with lymphocytic choriomeningitis virus (LCMV), vaccinia virus (VV), and vesicular stomatitis virus (VSV). Ex vivo CTL activity was consistently reduced by a factor of two to six for the different viruses. CTL responses after restimulation in vitro were similarly reduced unless exogenous cytokines were added. In the presence of interleukin-2 or concanavalin A supernatant, Itk-deficient and control mice responded similarly. Interestingly, while LCMV was completely eliminated by day 8 in both Itk-deficient and control mice, VV cleared from itk-/- mice with delayed kinetics. Antibody responses were evaluated after VSV infection. Both the T-cell-independent neutralizing immunoglobulin M (IgM) and the T-cell-dependent IgG responses were similar in Itk-deficient and control mice. Taken together, the results show that CTL responses are reduced in the absence of Itk whereas antiviral B-cell responses are not affected. 相似文献
997.
998.
RL Bayer SM Lichtman SL Allen DR Budman A Buchbinder J Fetten J Kolitz J Loscalzo 《Canadian Metallurgical Quarterly》1999,60(1):70-71
A rare cause of a spontaneous, life threatening coagulopathy in adults is the development of autoantibodies to factor VIII. We recently had the opportunity to treat seven patients with this disorder. After stabilization, they were given a regimen consisting of prednisone and oral cyclophosphamide. All patients had a complete response to treatment. The median time to response was three weeks. Durable remissions were achieved, making this oral regimen an acceptable treatment for this disorder. 相似文献
999.
H Le-Niculescu E Bonfoco Y Kasuya FX Claret DR Green M Karin 《Canadian Metallurgical Quarterly》1999,19(1):751-763
The JNK pathway modulates AP-1 activity. While in some cells it may have proliferative and protective roles, in neuronal cells it is involved in apoptosis in response to stress or withdrawal of survival signals. To understand how JNK activation leads to apoptosis, we used PC12 cells and primary neuronal cultures. In PC12 cells, deliberate JNK activation is followed by induction of Fas ligand (FasL) expression and apoptosis. JNK activation detected by c-Jun phosphorylation and FasL induction are also observed after removal of either nerve growth factor from differentiated PC12 cells or KCl from primary cerebellar granule neurons (CGCs). Sequestation of FasL by incubation with a Fas-Fc decoy inhibits apoptosis in all three cases. CGCs derived from gld mice (defective in FasL) are less sensitive to apoptosis caused by KCl removal than wild-type neurons. In PC12 cells, protection is also conferred by a c-Jun mutant lacking JNK phosphoacceptor sites and a small molecule inhibitor of p38 mitogen-activated protein kinase and JNK, which inhibits FasL induction. Hence, the JNK-to-c-Jun-to-FasL pathway is an important mediator of stress-induced neuronal apoptosis. 相似文献
1000.
S Miotti DR Negri O Valota M Calabrese RL Bolhuis JW Gratama MI Colnaghi S Canevari 《Canadian Metallurgical Quarterly》1999,84(1):62-68
OBJECTIVE: The types and amounts of crime experienced by persons with severe mental illness were examined to better understand criminal victimization in this population. METHODS: Subjects were 331 involuntarily admitted psychiatric inpatients who were ordered by the court to outpatient commitment after discharge. Extensive interviews provided information on subjects' experience with crime in the previous four months and their perceived vulnerability to victimization, as well as on their living conditions and substance use. Medical records provided clinical data. RESULTS: The rate of nonviolent criminal victimization (22.4 percent) was similar to that in the general population (21.1 percent). The rate of violent criminal victimization was two and a half times greater than in the general population--8.2 percent versus 3.1 percent. Being an urban resident, using alcohol or drugs, having a secondary diagnosis of a personality disorder, and experiencing transient living conditions before hospitalization were significantly associated with being the victim of a crime. In the multivariate analysis, substance use and transient living conditions were strong predictors of criminal victimization; no demographic or clinical variable was a significant predictor. (Given the relatively high crime rates, subjects' perceived vulnerability to victimization was unexpectedly low; only 16.3 percent expressed concerns about personal safety. Those with a higher level of education expressed greater feelings of vulnerability. CONCLUSIONS: The study found a substantial rate of violent criminal victimization among persons with severe and persistent mental illness. Results suggest that substance use and homelessness make criminal victimization more likely. 相似文献