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1.
An extensible conceptual model for recording design decisions and other supporting information is described along with the tool shell OSC in which it is embedded. The OSC shell consists of a design database and a family of query, manipulation, and extension facilities. The design database maintains a record of the design process. The extension facilities can be used to enrich the design database scheme incrementally and create new query or manipulation facilities. The core model provides a base language for describing the design process. Extension facilities augment this basis with more powerful, customized facilities. The implementation of the OSC shell using ESSAIM, an expert-system shell based on Smalltalk, is discussed  相似文献   
2.
The increasing prevalence of inflammatory diseases and the adverse effects associated with the long-term use of current anti-inflammatory therapies prompt the identification of alternative approaches to reestablish immune balance. Apigenin, an abundant dietary flavonoid, is emerging as a potential regulator of inflammation. Here, we show that apigenin has immune-regulatory activity in vivo. Apigenin conferred survival to mice treated with a lethal dose of Lipopolysaccharide (LPS) restoring normal cardiac function and heart mitochondrial Complex I activity. Despite the adverse effects associated with high levels of splenocyte apoptosis in septic models, apigenin had no effect on reducing cell death. However, we found that apigenin decreased LPS-induced apoptosis in lungs, infiltration of inflammatory cells and chemotactic factors’ accumulation, re-establishing normal lung architecture. Using NF-κB luciferase transgenic mice, we found that apigenin effectively modulated NF-κB activity in the lungs, suggesting the ability of dietary compounds to exert immune-regulatory activity in an organ-specific manner. Collectively, these findings provide novel insights into the underlying immune-regulatory mechanisms of dietary nutraceuticals in vivo.  相似文献   
3.
Steel fiber-reinforced concrete (SFRC) has been traditionally applied to pavements or tunnelling. However, classical structural applications have not been developed so fully. This paper examines different reasons which may justify the lack of this application. Several technologies on the fiber dosing system are presented and assessed. The SFRC reception control and acceptance criteria have been developed in accordance with the upcoming Spanish code. Adopting such criteria is justified on previous experiences and test viability under cast-in-place conditions. Some lines of action to promote the use of fibers with structural purposes are proposed. Two examples of recent applications are also set out, and a justification of the convenience of SFRC in terms of structural evaluation and durability under seawater conditions is provided.  相似文献   
4.
There has been an increasing focus on global warming, emission of green house gases (GHG), and the problems this might create. In this article, we review the trend in sustainable and renewable electricity generation in South America, where the generation portfolio increasingly depends on thermal generation, in particular gas. South America is a region that has relatively low emissions, but the current development is not desirable in environmental terms. We analyze the underlying reasons for this development, which is related to security of supply, deregulation, and the cost of renewable energy. We review and discuss the policies to promote renewables in the region. We analyze the potential advantages and drawbacks of different types of market interventions, such as direct subsidies that create potentially strong market distortions, more sophisticated market interventions that might be less intrusive but not necessarily as effective as, e.g. firm energy markets. We also review market-based solutions such as the Clean Market Mechanism and its potential, and the use of renewable electricity in non-interconnected zones, which might be one of the most economically attractive applications of renewables. However, without a stronger and more aggressive intervention from the governments in the region it is unlikely that the increase in thermal generation can be stopped.  相似文献   
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6.
The intermodal transport chain can become more efficient by means of a good organization of the drayage movements. Drayage in intermodal container terminals involves the pick up or delivery of containers at customer locations, and the main objective is normally the assignment of transportation tasks to the different vehicles, often with the presence of time windows. The literature shows some works on centralized drayage management, but most of them consider the problem only from a static and deterministic perspective, whereas the work we present here incorporates the knowledge of the real-time position of the vehicles, which permanently enables the planner to reassign tasks in case the problem conditions change. This exact knowledge of position of the vehicles is possible thanks to a geographic positioning system by satellite (GPS, Galileo, Glonass), and the results show that this additional data can be used to dynamically improve the solution.  相似文献   
7.
Initially thought to act as tissue replacement, cultured epithelial allografts are now known to work by providing a potent stimulus for healing. In a similar fashion, we believe that traditional autografts may also provide a stimulus to help heal chronic wounds, thus acting as pharmacological agents for healing. We attempted to assess the possibility of augmenting the stimulatory properties of donor skin by initiating the healing process in the donor region prior to grafting. This was accomplished by pre-wounding the donor area 3 days prior to harvesting the donor skin. We compared these 'pre-wounded' grafts to those harvested immediately. Two patients underwent punch grafting for chronic leg ulceration. Half of the ulcer was grafted with donor skin harvested from an area that was pre-wounded and the other half from freshly harvested skin. We evaluated each for improvement of granulation tissue and degree of edge effect (migration of the previously dormant wound edges). All the grafts did well. There was marked improvement in granulation tissue in the ulcer bed after grafting, and the obvious presence of an edge effect. The edge effect was increased on the site where the pre-wounded grafts were placed. It may be possible to augment the growth stimulatory properties of donor skin. This may offer therapeutic options in patients with chronic wounds.  相似文献   
8.
The use of high-dose pancreatic enzymes by patients with cystic fibrosis was associated with the development of fibrosing colonopathy. Preliminary studies indicated that the infusion of high-dose pancreatic enzymes alone did not cause intestinal damage. We hypothesized that cystic fibrosis patients that developed fibrosing colonopathy had increased intestinal permeability. Our goal was to develop a rat model for pancreatic enzyme-induced fibrosing colonopathy by increasing intestinal permeability with the use of indomethacin. Pancreatic enzymes, 150,000 units/kg/day, and indomethacin, 3 mg/kg/day, alone and in combination were administered via duodenal catheter to rats for 10 days. Indomethacin and pancreatic enzymes caused intestinal damage, resulting in significant increases in the total number of ulcers (P < 0.007), the number of severe ulcers (P < 0.003), and ulcers in the cecum and colon (P < 0.0007). We conclude that the combination of indomethacin and pancreatic enzymes acts synergistically to cause damage to the intestine.  相似文献   
9.
This work assessed the risk of protozoa in 10 school restaurants in Armenia (Quindío, Colombia) by analyzing the presence of Cryptosporidium spp, Giardia duodenalis, Blastocystis, and Cyclospora cayetanensis DNA in the food, water, and living and inert surfaces of school restaurants and in stools of children who ate at these restaurants. Of the 213 food, water, and surface samples, 6.6% were positive using PCR to test DNA for Blastocystis; 3.8% for Cryptosporidium spp; 0.9% for G. duodenalis; and 0% for C. cayetanensis. In 187 stool samples analyzed via microscopy from children who attended the restaurants, 40 (21.4%) were positive for Blastocystis and 21 (11.2%) were positive for Giardia spp. Via PCR, 20 (10.7%) were positive for Cryptosporidium and 0 (0%) for C. cayetanensis. A higher positivity in children's stools for Blastocystis spp was correlated with lower compliance in property conditions and for higher positivity of Giardia spp in children's stool was related to lower knowledge by food manipulators. Inspection scores can identify restaurants with higher risk for protozoa infection.  相似文献   
10.
Cubic boron-carbon-nitrogen c-BC2N films were synthesized in a laser ablation system using a target of B4C with 99.99% of purity and silicon substrates (111). The discharge atmosphere for the films growth was a CH4 + N2 mixture. The substrate temperature increased from room temperature to 650 °C. The chemical composition and bonding configuration were studied by X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES), finding B-N, B-C and C-C bonds. Moreover, the crystallographic microstructure was analyzed by means of X ray diffraction (XRD) and transmission electron microscopy (TEM), showing the presence of (111), (200) and (220) planes belonging to a diamond like cubic structure. Finally, an increase in the coating hardness as a function of the substrate temperature was observed, especially for temperatures higher than 530 °C.  相似文献   
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