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101.
102.
Juvenile myelomonocytic leukemia (JMML) carries a poor prognosis. The endogenous production of cytokines by the JMML cells contributes to their growth and therapeutic resistance. Interleukin (IL)-4, IL-10, and IL-13 inhibit cytokine production in monocytes. We have now studied whether these cytokines can inhibit JMML cell cytokine production, thereby potentially reducing the malignant cell load in this disorder. We found that IL-10, but not IL-4 or IL-13, dose dependently inhibited JMML cell production of the hemopoietic growth factors granulocyte-macrophage colony-stimulating factor, tumor necrosis factor alpha, and IL-1beta. Similarly, IL-10, but not IL-4 or IL-13, suppressed JMML colony formation and cell viability. This was not due to the absence of receptors because we could detect mRNAs for the IL-4 and the IL-13 receptor alpha subunits and the IL-2 common gamma subunit in JMML cells. Furthermore, the receptors were active since both IL-4 and IL-13 up-regulated surface expression of MHC class II and down-regulated CD14 antigens on JMML cells and monocytes. Unlike activated monocytes, the JMML cells did not produce IL-10. It is suggested that the loss of cytokine inhibitory effects of IL-4 and IL-13 could play a role in the pathogenesis of this disorder. On the other hand, the inhibition of cytokine production, growth, and viability of JMML cells by IL-10 suggests that this cytokine may have a therapeutic potential in JMML.  相似文献   
103.
Organic semiconductor to metal Schottky contacts have been widely used in electronic devices and to investigate the properties of organic semiconductors. In designing and characterizing these devices the full depletion approximation is used. The analytical and numerical simulations presented in this paper suggest that this approximation is not generally valid. Simulations of a Schottky contact between regioregular-poly 3 hexylthiophene (rr-P3HT) and aluminum show that this approximation becomes worse as molecular order decreases, with the potential profile increasingly deviating from the expected quadratic function of position. Also the depletion width decreasing well below that predicted using the approximation. In this work the slope of the band tail is used as a measure of disorder.  相似文献   
104.
Lab‐on‐a‐chip (LOC) integrated microfluidics has been a powerful tool for new developments in analytical chemistry. These microfluidic systems enable the miniaturization, integration and automation of complex biochemical assays through the reduction of reagent use and enabling portability. Electroosmotic micropumps could be employed as powerful tools to generate required flow in point of care (POC) devices. In the present study, parallel electroosmotic micropumps are investigated to improve the efficiency of simple micropumps. According to the results, parallel micropumps generate higher flow rate in comparison with conventional electroosmotic pump. In the last decade, a large variety of non‐Newtonian fluids have been utilized in biomedical application but requirements for a POC device such as high efficient driving flow, miniaturization and simple handling of POC devices remain unmet. As a consequence, in this study, power law model as non‐Newtonian fluids that flow through the parallel micropumps are investigated in order to enhance fluid pumping and decreasing voltage requirement.. It is found that as the power law index increases the mass flow rate decreases. Also, the flow rate is almost constant for the higher power law index. Obtained results, demonstrated that parallel micropump could enhance pumping of non‐Newtonian fluid (blood) up to 30%. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
105.
Earth science phenomena are primarily spatially dependent with variations occurring on varying scales. Geostatistics is a well-known approach for the assessment of spatial models of regionalized variables, such as porosity. In this study, we used the results of 953 Lugeon tests (402 tests in exploratory wells and 550 tests in grouting wells) to assess effective porosity and karst development at the Tangab Dam site, Iran. Lugeon values were first normalized, following which the variogram method (i.e., range, sill, and nugget effect) was used to identify the spatial variability of Lugeon values. A high correlation range of 200 m was obtained along the grout curtain galleries, while the range was about 40 m in the vertical direction. The simple kriging method with Gaussian variograms was determined to be the best method for estimating the Lugeon values in the study area using cross validation-criteria (e.g., RMSE = 0.835 and ρ = 0.914). Spatial variation of Lugeon values was mapped using a simulated annealing approach. The analysis revealed: (1) a higher potential for karst development on the left abutment of the Tangab Dam site, (2) the average of simulated Lugeon values decreased from values of about 180 close to the ground surface at 1,440 m a.s.l. to lower values of about 50 at 1,260 m a.s.l., and (3) high Lugeon values in the abutments of the dam site approximately followed the 15° bedrock dip, which confirms the potential development of karst features in the Asmari limestone. A schematic model for development of karst at the Tangab Dam site is proposed based on hydrogeological data and results of simulated Lugeon values around the dam site.  相似文献   
106.
In this paper, a new noncontact ultrasonic magnetic abrasive finishing mechanism is presented. An ultrasonic vibration producer is used to vibrate the permanent magnets. The ferromagnetic steel grits in the created magnetic field form a flexible finishing tool. To take advantage of cavitation collapse pressure, the finishing zone components are immersed in water. The present work also studies the effect of parameters, i.e., time duration for finishing and working gap between magnetic poles and the workpiece on the surface roughness (Ra). The microscopic pictures and the roughness profile diagrams demonstrate the advantages of the proposed method.  相似文献   
107.
We used novel synthetic conditions of precipitation polymerization to obtain uniformly sized molecularly imprinted nanospheres of dipyridamole for application in the design of new drug delivery systems. In addition, the morphology, drug release, and binding properties of molecularly imprinted polymers (MIPs) were studied, and the effects of morphology on other properties were investigated. The MIPs prepared by acetonitrile/chloroform (19:1, v/v) were uniformly sized nanospheres with an average mean diameter of approximately 88 nm at a wetted state, 50 nm at a dry state, and a polydispersity index of 0.062. The imprinted nanospheres showed excellent binding properties and had 62.7% of template binding compared with 17.1% of its blank polymer. The imprinted nanospheres with 67.5 (mg template/of polymer) of binding capacity had better imprinting efficiency than the 50.5% of binding capacity shown by irregularly shaped MIP particles that were prepared by chloroform. The molecular binding abilities of imprinted nanospheres in human serum were evaluated by HPLC analysis (binding about 77% of dipyridamole). Results from release experiments of MIPs showed a very slow, controlled, and satisfactory release of dipyridamole. The loaded drug was released up to 99% in 17 days for nanospheres and 22 days for irregularly shaped particles.  相似文献   
108.
Potentially, TOC content is affected by logging data in a source rock (density, sonic, neutron and resistivity logs). Hence, to analyze these logs, which we make a quick and reliable assessment of a source rock. So, it is a quick and economically cheaper method rather than direct geochemical analysis. A source rock interval poses to less density, lower velocity, higher sonic porosity, higher gamma ray values and increase in resistivity. In this research, Gadvan Formation was studied in two boreholes as potential of source rock. The log data of two wells were used to construct of intelligent models in a source rock of the South Pars Gas field in southwest of Iran. A suite of geophysical logs (neutron, density, sonic and resistivity logs) and cutting chip data samples data were applied for determining TOC content of this formation. Rock-Eval pyrolysis data reveal that Gadvan Formation is poor source rock (less than 0.5%). Hence we attempted a correlation between geophysical data and direct TOC content measurements of using ? Log R, Rock-Eval, neural network and fuzzy logic techniques.The results showed that intelligent models were successful for prediction of TOC content from conventional well logs data. Meanwhile, similar responses from other different intelligent methods indicated that their validity for solving complex problems.  相似文献   
109.
BACKGROUND: Efficient use of energy in agriculture is one of the conditions for sustainable agricultural production. This study applies the data envelopment analysis (DEA) approach to the data of 95 randomly selected farms to investigate the technical and scale efficiencies of farmers with respect to energy use for sunflower production in Golestan province, Iran. The study also helps to identify the wasteful usage and the optimum level of energy from different inputs. RESULTS: According to the results of DEA models, about 36% of farmers were found to be technically efficient and the mean efficiency of sunflower producers was found to be 0.87 and 0.96 under the constant and variable returns to scale assumptions respectively. The optimum energy requirement was calculated as 8448.3 MJ ha?1; accordingly, a potential reduction of 10.8% (1020.3 MJ ha?1) in total energy input could be achieved by raising the performance of farmers to the highest level. CONCLUSION: Applying a better machinery management technique and conservation tillage methods, application of fertilisers by performance monitoring and utilisation of alternative sources of energy such as compost and chopped residues may be the pathways for improving energy productivity and reducing the environmental footprint. Copyright © 2011 Society of Chemical Industry  相似文献   
110.
In this paper, the local radial point interpolation method (LRPIM) is developed for the investigation of time dependent problems in solid mechanics. By a new integration scheme considered for the obtained meshless weak form, integrands are approximated up to the second order of the Taylor series and the integrals are evaluated on some points, which are located inside the local quadrature domains, called integration points. In order to show the efficiency of the suggested method, some time dependent mechanical problems are considered for the engineering structures such as beams and plates, which are subjected to dynamical loads, the deflections and stresses are evaluated. Finally, it has been shown that using the proposed method greatly reduces the number of integration points without affecting the accuracy of the results.  相似文献   
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