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41.
This paper documents the design, competing systems, results, and conclusions of the CADE-14 ATP System Competition (CASC-14).  相似文献   
42.
Increasing evidence suggests that non-steroidal anti-inflammatory drugs (NSAID) differ in gastrotoxicity. This study aimed to compare the effects of a short-acting NSAID, tiaprofenic acid, with indomethacin on experimental gastric ulcer healing in a rat model. Similar anti-inflammatory and prostaglandin-inhibitory doses of indomethacin (1 mg/kg) and tiaprofenic acid (2 mg/kg) were administered to rats with acetic acid-induced ulcers. After 2 weeks treatment, rats were killed and ulcer size determined. In addition, histological sections of ulcers were assessed for ulcer contraction and mucosal regeneration. The degree of inhibition of prostaglandin E2 (PGE2) synthesis was 72% at 2 h after tiaprofenic acid and 64% at 2 h after indomethacin administration, respectively. Rats treated with indomethacin for 2 weeks had significantly larger ulcers, both macroscopically and microscopically, than controls. Rats treated with tiaprofenic acid for 2 weeks had ulcers of a similar size to those of controls. Indomethacin-treated ulcers showed a failure in mucosal regeneration. Tiaprofenic acid-treated ulcers had significantly more regeneration than indomethacin-treated ulcers. We conclude that tiaprofenic acid inhibits mucosal prostaglandin levels but does not inhibit experimental gastric ulcer healing. These findings suggest that inhibition of PGE2 synthesis is not the only factor in generating gastrotoxicity and that a shift to low gastrotoxic NSAID may be clinically worthwhile.  相似文献   
43.
The preoperative assessment of sciatica secondary to a herniated intervertebral disk has been radically changed over recent years due to the development of percutaneous treatment techniques which now offer an alternative to surgery. After recalling the terminology used for the position of a herniated lumbar disk in relation to the posterior common vertebral ligament (subligamentous or transligamentous hernia) and to describe whether or not the hernia is detached from the original disk (excluded or non-excluded hernia), the authors review the current state of the art of imaging for each type of herniated lumbar intervertebral disk.  相似文献   
44.
On July 24, 2010, 21 people died and more than 500 were injured in a stampede at the Loveparade, a music festival, in Duisburg, Germany. Although this tragic incident is but one among many terrible crowd disasters that occur during pilgrimage, sports events, or other mass gatherings, it stands out for it has been well documented: there were a total of seven security cameras monitoring the Loveparade and the chain of events that led to disaster was meticulously reconstructed.In this paper, we present an automatic, video-based analysis of the events in Duisburg. While physical models and simulations of human crowd behavior have been reported before, to the best of our knowledge, automatic vision systems that detect congestions and dangerous crowd turbulences in real world settings were not reported yet. Derived from lessons learned from the video footage of the Loveparade, our system is able to detect motion patterns that characterize crowd behavior in stampedes. Based on our analysis, we propose methods for the detection and early warning of dangerous situations during mass events. Since our approach mainly relies on optical flow computations, it runs in real-time and preserves privacy of the people being monitored.  相似文献   
45.
Clones are generally considered bad programming practice in software engineering folklore. They are identified as a bad smell?(Fowler et?al. 1999) and a major contributor to project maintenance difficulties. Clones inherently cause code bloat, thus increasing project size and maintenance costs. In this work, we try to validate the conventional wisdom empirically to see whether cloning makes code more defect prone. This paper analyses the relationship between cloning and defect proneness. For the four medium to large open source projects that we studied, we find that, first, the great majority of bugs are not significantly associated with clones. Second, we find that clones may be less defect prone than non-cloned code. Third, we find little evidence that clones with more copies are actually more error prone. Fourth, we find little evidence to support the claim that clone groups that span more than one file or directory are more defect prone than collocated clones. Finally, we find that developers do not need to put a disproportionately higher effort to fix clone dense bugs. Our findings do not support the claim that clones are really a “bad smell”?(Fowler et?al. 1999). Perhaps we can clone, and breathe easily, at the same?time.  相似文献   
46.
Cloud computing services have recently become a ubiquitous service delivery model, covering a wide range of applications from personal file sharing to being an enterprise data warehouse. Building green data center networks providing cloud computing services is an emerging trend in the Information and Communication Technology (ICT) industry, because of Global Warming and the potential GHG emissions resulting from cloud services. As one of the first worldwide initiatives provisioning ICT services entirely based on renewable energy such as solar, wind and hydroelectricity across Canada and around the world, the GreenStar Network (GSN) was developed to dynamically transport user services to be processed in data centers built in proximity to green energy sources, reducing Greenhouse Gas (GHG) emissions of ICT equipments. Regarding the current approach, which focuses mainly in reducing energy consumption at the micro-level through energy efficiency improvements, the overall energy consumption will eventually increase due to the growing demand from new services and users, resulting in an increase in GHG emissions. Based on the cooperation between Mantychore FP7 and the GSN, our approach is, therefore, much broader and more appropriate because it focuses on GHG emission reductions at the macro-level. This article presents some outcomes of our implementation of such a network model, which spans multiple green nodes in Canada, Europe and the USA. The network provides cloud computing services based on dynamic provision of network slices through relocation of virtual data centers.  相似文献   
47.
Computer aided design of microwave monolithic integrated circuits must combine two different fields. The first domain is the simulation of microwave circuits taking into account non linear aspects development of time domain and harmonic balance simulation algorithms specialized for microwave circuits. In the second place are found, the layout algorithms which were developed for logic circuits (on Si or GaAs). The association of these two types of algorithms leads to the constitution of aCad workstation for microwave monolithic integrated circuits. Two examples of design and realization of integrated circuits with these tools are presented.  相似文献   
48.
The development of nanocarriers (NC) for biomedical applications has gained large interest due to their potential to co-deliver drugs in a cell-type-targeting manner. However, depending on their surface characteristics, NC accumulate serum factors, termed protein corona, which may affect their cellular binding. We have previously shown that NC coated with carbohydrates to enable biocompatibility triggered the lectin-dependent complement pathway, resulting in enhanced binding to B cells via complement receptor (CR)1/2. Here we show that such NC also engaged all types of splenic leukocytes known to express CR3 at a high rate when NC were pre-incubated with native mouse serum resulting in complement opsonization. By focusing on dendritic cells (DC) as an important antigen-presenting cell type, we show that CR3 was essential for binding/uptake of complement-opsonized NC, whereas CR4, which in mouse is specifically expressed by DC, played no role. Further, a minor B cell subpopulation (B-1), which is important for first-line pathogen responses, and co-expressed CR1/2 and CR3, in general, engaged NC to a much higher extent than normal B cells. Here, we identified CR-1/2 as necessary for binding of complement-opsonized NC, whereas CR3 was dispensable. Interestingly, the binding of complement-opsonized NC to both DC and B-1 cells affected the expression of activation markers. Our findings may have important implications for the design of nano-vaccines against infectious diseases, which codeliver pathogen-specific protein antigen and adjuvant, aimed to induce a broad adaptive cellular and humoral immune response by inducing cytotoxic T lymphocytes that kill infected cells and pathogen-neutralizing antibodies, respectively. Decoration of nano-vaccines either with carbohydrates to trigger complement activation in vivo or with active complement may result in concomitant targeting of DC and B cells and thereby may strongly enhance the extent of dual cellular/humoral immune responses.  相似文献   
49.
The anoctamin (TMEM16) family of transmembrane protein consists of ten members in vertebrates, which act as Ca2+-dependent ion channels and/or Ca2+-dependent scramblases. ANO4 which is primarily expressed in the CNS and certain endocrine glands, has been associated with various neuronal disorders. Therefore, we focused our study on prioritizing missense mutations that are assumed to alter the structure and stability of ANO4 protein. We employed a wide array of evolution and structure based in silico prediction methods to identify potentially deleterious missense mutations in the ANO4 gene. Identified pathogenic mutations were then mapped to the modeled human ANO4 structure and the effects of missense mutations were studied on the atomic level using molecular dynamics simulations. Our data show that the G80A and A500T mutations significantly alter the stability of the mutant proteins, thus providing new perspective on the role of missense mutations in ANO4 gene. Results obtained in this study may help to identify disease associated mutations which affect ANO4 protein structure and function and might facilitate future functional characterization of ANO4.  相似文献   
50.
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