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101.
The potential use of plasma polymer coatings as substrates for serum-free expansion of limbal epithelial cells was investigated. Preliminary studies using a human corneal epithelial cell line showed that acrylic acid-coated surfaces performed better than allyl amine and allyl alcohol coated surfaces in terms of cell metabolic activity and confluence as assessed using the MTT assay. Subsequently, the proliferation and maturity of primary human limbal epithelial cells in co-culture with growth arrested 3T3 fibroblasts on a range of acrylic acid plasma coated surfaces, octadiene plasma coated surfaces and tissue culture plastic was investigated using MTT and cytokeratin 3 immunostaining. The cells performed better in the presence of serum on all surfaces. However, the acrylic acid coated surfaces successfully sustained a serum-free fibroblast/epithelial cell co-culture. The metabolic activity of the epithelial cells was superior on the acrylic acid coated surfaces than on tissue culture plastic in serum-free conditions and their levels of differentiation were not significantly higher than in the presence of serum. These results suggest that these surfaces can be used successfully for the serum-free expansion of human limbal epithelial cells.  相似文献   
102.
The purpose of this research was to evaluate the nutritional quality and acceptability of a meat product formulated with mechanically deboned poultry meat (40%), bovine plasma (40%) and bovine red cells (3%) as major ingredients. Proteins, fat, humidity and ash were determined by AOAC procedure, iron and calcium by Atomic Absorption Spectrometry and essential amino acids by HPLC. Biological evaluation was performed using digestibility and PER procedures. To evaluate the acceptability (flavor, color and odor) of the product were used 277 children. Results indicated that 100 g of the formulated meat product contain 10.7 g of proteins, 4.4 g of fat, 68.6 g of humidity, 2.9 g of ash, 4.9 mg of iron, 46.6 mg of calcium. Essential amino acids are above the FAO requirements for a highly nutritional protein digestibility (92.4%) and PER (2.18). Acceptability was 91.3% for flavor, 81.2% for color and 92.4% for odor. The high nutritional quality and acceptability along with the low cost make this meat product suitable for government social programs.  相似文献   
103.
In this work, 10.6-microm pulsed laser damage studies were performed on reflective and antireflective coatings on Si, Ge, and ZnSe substrates. Single-pulse damage threshold determinations were conducted at two different laser spot sizes. A high-resolution TV system was used to perform visible light scattering studies, the results of which correlated with laser damage at 10.6 microm. Single-pulse damage determinations along with visible light scattering and multipulse damage determinations indicate that coating performance can be improved substantially by reducing the density of scattering centers present on the coatings.  相似文献   
104.
Ongoing developments in cardiac modelling have resulted, in particular, in the development of advanced and increasingly complex computational frameworks for simulating cardiac tissue electrophysiology. The goal of these simulations is often to represent the detailed physiology and pathologies of the heart using codes that exploit the computational potential of high-performance computing architectures. These developments have rapidly progressed the simulation capacity of cardiac virtual physiological human style models; however, they have also made it increasingly challenging to verify that a given code provides a faithful representation of the purported governing equations and corresponding solution techniques. This study provides the first cardiac tissue electrophysiology simulation benchmark to allow these codes to be verified. The benchmark was successfully evaluated on 11 simulation platforms to generate a consensus gold-standard converged solution. The benchmark definition in combination with the gold-standard solution can now be used to verify new simulation codes and numerical methods in the future.  相似文献   
105.
小型与大型水电站两者的装机容量之间相差悬殊,这造成一种使两者在一个电力系统的负荷图中联合运行的可能性。因而,小水电站的作用不应是弥补电力的不足,而是提供一种最优电源,从而节省火电站的燃料或减少进口的电能(即只装设重复容量一译  相似文献   
106.
Surface contouring by phase-shifting digital holography is proposed and verified by experiments and numerical simulations. Digital holograms are recorded before and after mode hopping of a laser diode subject to current tuning, and the difference of the reconstructed phases at each wavelength is computed to deliver surface contours of a diffusely reflecting surface. Since normal incidence on the object is employed, the method does not need the removal of the tilt component and is free from the shadowing effect as advantages over the dual-incidence method proposed before by the first author.  相似文献   
107.
Remineralization effects of xylitol on demineralized enamel   总被引:3,自引:0,他引:3  
We morphologically determined the effects of xylitol on the remineralization of artificially demineralized enamel. The samples were demineralized and then immersed in a remineralizing solution with or without 20% xylitol at 37 degrees C for 2 weeks. Samples were observed using contact microradiography, a multipurpose image processor (MIP) and a high-resolution electron microscope (HRTEM). Contact microradiography indicated that remineralization occurred in the surface and deep layers of samples immersed in a non-xylitol solution. Samples immersed in a xylitol solution demonstrated less mineralization in the outer 10 microm of the outermost surface layers, but more mineralization in the middle and deep layers, than was observed in the non-xylitol samples. The MIP evaluation indicated that remineralization was more prominent in layers at depths of 50-60 microm in the xylitol samples than in the non-xylitol samples. Observation of the xylitol samples by HRTEM revealed crystals of various sizes and irregular shapes with unclear crystal angles in the outermost surface layers. In the middle layers, they had thickened and angles of crystals are clear. These results indicate that xylitol can induce remineralization of deeper layers of demineralized enamel by facilitating Ca2+ movement and accessibility.  相似文献   
108.
This paper involves the investigations of the chilled water and ice cold thermal storage technologies along with the associated operating strategies for the air conditioning(AC) systems of the typical office buildings in Saudi Arabia, so as to reduce the electricity energy consumption during the peak load periods. In Saudi Arabia, the extensive use of AC for indoor cooling in offices composes a large proportion of the annual peak electricity demand. The very high temperatures over long summer periods, extending from May to October, and the low cost of energy are the key factors in the wide and extensive use of air conditioners in the kingdom. This intense cooling load adds up to the requirement increase in the capacity of power plants, which makes them under utilized during the off-peak periods. Thermal energy storage techniques are one of the effective demand-side energy management methods. Systems with cold storage shifts all or part of the electricity requirement from peak hours to off-peak hours to reduce demand charges and/or take advantage of off-peak rates. The investigations reveal that the cold thermal energy storage techniques are effective from both technical and economic perspectives in the reduction of energy consumption in the buildings during peak periods.  相似文献   
109.
110.
越来越多的光盘生产厂开始生产DVD光盘,对于大多数刚接触DVD光盘的生产者来说粘合是一个过去从未接触过的生产工艺,只有过去生产LD或MO的生产厂才累积有粘合的经验,这就是热融粘合法。现在UV固化粘合法有许多优势,但是Krauss-Maffei公司(以下称KM公司)的Martin Eichlseder先生提出了自己的观点,他认为不应忽视热融粘合法工艺,最新的研究成果将使它成为值得信赖的技术。  相似文献   
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