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Donnai-Barrow syndrome is associated with agenesis of the corpus callosum, congenital diaphragmatic hernia, facial dysmorphology, ocular anomalies, sensorineural hearing loss and developmental delay. By studying multiplex families, we mapped this disorder to chromosome 2q23.3-31.1 and identified LRP2 mutations in six families with Donnai-Barrow syndrome and one family with facio-oculo-acoustico-renal syndrome. LRP2 encodes megalin, a multiligand uptake receptor that regulates levels of diverse circulating compounds. This work implicates a pathway with potential pharmacological therapeutic targets.  相似文献   
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Reliability allocation problem is commonly treated using a closed-form expression relating the cost to reliability. A recent approach has introduced the use of discrete integer technique for un-repairable systems. This research addresses the allocation problem for repairable systems. It presents an integer formulation for finding the optimum selection of components based on the integer values of their Mean Time to Failure (MTTF) and Mean Time to Repair (MTTR). The objective is to minimize the total cost under a system reliability constraint, in addition to other physical constraints. Although, a closed-form expression relating the cost to reliability may not be a linear; however, in this research, the objective function will always be linear regardless of the shape of the equivalent continuous closed-form function. An example is solved using the proposed method and compared with the solution of the continuous closed-form version. The formulation for all possible system configurations, components and subsystems are also considered.  相似文献   
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The effect of alumina nanoparticle addition on the microstructure and tribological properties of a CuCrW alloy was investigated in this work.Mechanical alloying was carried out in a satellite ball mill.The tribological properties of the samples were evaluated using pin-on-disk wear tests with different pins (alumina,tungsten carbide,and steel pins).The results indicated that the tungsten carbide pin had a lower coefficient of friction than the alumina and steel pins because of its high hardness and low surface roughness.In addition,when the sliding rate was decreased,the weight-loss rate increased.The existence of alumina nanoparticles in the nanocomposite led to a lower weight-loss rate and to a change in the wear mechanism from adhesive to abrasive.  相似文献   
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Cellular and Molecular Life Sciences - A method for cultivatingSpirulina platensis in domestic raw sewage, coupled with pisciculture and water reclamation in an integrated recycling system, has...  相似文献   
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The interaction of salinity stress and plant residue quality on C mineralization kinetics in soil is not well understood. A laboratory experiment was conducted to study the effects of salinity stress on C mineralization kinetics in a soil amended with alfalfa, wheat and corn residues. A factorial combination of two salinity levels (0.97 and 18.2 dS/m) and four levels of plant residues (control, alfalfa, wheat and corn) with three replications was performed. A first order kinetic model was used to describe the C mineralization and to calculate the potentially mineralizable C. The CO2-C evolved under non-saline condition, ranged from 814.6 to 4842.4 mg CO2-C/kg in control and alfalfa residue-amended soils, respectively. Salinization reduced the rates of CO2 evolution by 18.7%, 6.2% and 5.2% in alfalfa, wheat and corn residue-amended soils, respectively. Potentially mineralizable C (C 0) was reduced significantly in salinized alfalfa residue-treated soils whereas, no significant difference was observed for control treatments as well as wheat and corn residue-treated soils. We concluded that the response pattern of C mineralization to salinity stress depended on the plant residue quality and duration of incubation.  相似文献   
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Summary Spirulina platensis has been grown in an outdoor pilot production unit, with an exposed surface area of 450 m2, on a medium consisting of raw domestic sewage supplemented with sodium bicarbonate and nitrate or urea fertilizer. The chemical composition and yield of the biomass grown on sewage-nitrate was comparable to that grown on synthetic medium. The protein content was much lower in the alga cultivated in sewage-urea medium.NBRI Research Publication No. 143 (NS).  相似文献   
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