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1.
Tissue engineering requires the precise positioning of mammalian cells and biomaterials on substrate surfaces or in preprocessed scaffolds. Although the development of 2D and 3D bioprinting technologies has made substantial progress in recent years, precise, cell-friendly, easy to use, and fast technologies for selecting and positioning mammalian cells with single cell precision are still in need. A new laser-based bioprinting approach is therefore presented, which allows the selection of individual cells from complex cell mixtures based on morphology or fluorescence and their transfer onto a 2D target substrate or a preprocessed 3D scaffold with single cell precision and high cell viability (93–99% cell survival, depending on cell type and substrate). In addition to precise cell positioning, this approach can also be used for the generation of 3D structures by transferring and depositing multiple hydrogel droplets. By further automating and combining this approach with other 3D printing technologies, such as two-photon stereolithography, it has a high potential of becoming a fast and versatile technology for the 2D and 3D bioprinting of mammalian cells with single cell resolution.  相似文献   
2.
Mine Water and the Environment - Acid mine drainage (AMD) is a major environmental challenge for the mining industry in northern climates. Laboratory-scale experiments were conducted to test...  相似文献   
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Mine Water and the Environment - Passive treatment is a promising, green technology that is increasingly being used for mine drainage treatment. However, several challenges remain concerning its...  相似文献   
5.
提出可以增加集合住宅受欢迎度的共鸣设计方法策略,这些策略不仅考虑到建筑本身的一些可能性,同时考虑到在空间和社会环境方面的要求,涵盖了物理的、心理的以及社会的因素;指出这类策略的应用带来了高度的用户接受度并使得适应性建筑在一个长时期内可以保持其价值.阐释在设计方法的帮助下,建筑物被记录和相互比较.  相似文献   
6.
Mirabelle plums represent a famous fruit from the Lorraine region, however little is known about their phytochemical composition. The oil of the fruit contained predominantly oleic acid (59%) and linoleic acid (29%). The total content of phenolic antioxidants in the whole fruits was 5.338 g/kg with 456 mg/kg (9%), 701 mg/kg (13%) and 4159 mg/kg (78%) detected in the peels, flesh and pits respectively. The peels contained solely 3,4-dihydroxybenzoic acid (270 mg/kg) and rutin (186 mg/kg), the flesh exclusively echinoids (723 mg/kg), whereas the pits contained a rich variety of phenolic compounds (4.2 g/kg) dominated by amygdalin (3.8 g/kg), but with significant contributions from vanillin (102 mg/kg), guajacyl-glycerin-coniferyl aldehyde isomers (87 mg/kg), dehydro-diconiferyl aldehyde (52 mg/kg), and vanillin diglucoside (48 mg/kg). Of the major phenolic compounds tested across a range of in vitro assays, rutin was the superior antioxidant.  相似文献   
7.
Galactomannan (GM) is widely used for detection of invasive aspergillosis in high-risk haemato-oncology patients. Recent publications have reported a lack of repeatability of GM detection. The objective of this retrospective study was to assess the repeatability of GM levels during storage of clinical samples. In a GM screening strategy, positive sera were repeat tested as per manufacturer’s recommendations. Short-term (ST) storage of samples was at +4 °C while long-term (LT) storage was at −80 °C. Bronchoalveolar (BAL) fluid was also repeating tested after ST storage and LT storage. Wilcoxon Signed Ranks Test was employed to assess the repeatability of GM levels. In a subset of 14 GM positive sera, repeat testing was performed on both the original serum and ethylenediaminetetraacetic acid (EDTA) pre-treated sample. There was a significant reduction in GM signals on repeat testing following ST storage (median GM index: 0.65 vs. 0.19; p < 0.001) and LT storage (median GM index: 0.56 vs. 0.10; p < 0.001) of serum samples. Of samples that were initially GM positive, an average GM index reduction of 50% was seen, with approximately two-thirds becoming GM negative on repeat testing of the same sample. In contrast, GM signal loss was not seen on repeat testing of BAL fluid following ST or LT storage. When GM positive serum samples were repeat tested using EDTA pre-treated serum from the first step of the testing protocol, all samples remained GM positive. In contrast, when the same samples were repeat tested from the original collected serum, 9 samples (64%) became GM negative. The significant reduction in GM signals during ST and LT storage of serum samples has implications for clinical management. Although the reasons for GM decline are unknown, they occur prior to the EDTA pre-treatment stage, indicating that the time from phlebotomy to testing should be minimized. BAL fluid GM index values remain stable.  相似文献   
8.
The authors demonstrate the application of a commercially available SiGe heterojunction bipolar transistor monolithic microwave integrated circuit technology to active mixers in future communication systems at 5.7 GHz and above. This technology can be used to realise circuits with less than 50 mW power consumption, conversion gains above 15 dB and small double sideband noise figures of 3.6 and 9.4 dB for 5.7 and 11.2 GHz Gilbert cell mixer circuits, respectively  相似文献   
9.
��The Sinian pool of Weiyuan gasfield is a black one controlled by structure.In this paper,The producing performance of water's entering into gas wells is simply stated,the operation method of water-prod- ucing gas wells is summarized and the advantage or drawback of various technology of water withdrawal in gas production is also appraised,It is pointed out that using the technique of intensifying water withdrawal is an efficient way for synthetically administering and well developing this gas pool.  相似文献   
10.
The planning and design of a 50-kW experimental solar thermal power plant which was to have a selective coating on the absorber initiated an investigation into black chrome deposition in order to find the most suitable type of solution for a continuous plating process. Acetic acid-type and fluorosilic acid-type electrolytes were tested with a variety of additives and deposition parameters. The best results were achieved with an electrolyte containing fluorosilic acid as the catalyst. With this solution, coatings with optimum thermo-optical properties were formed in only 22 sec at current densities of 0.5 A cm−2 and a temperature of 15°C. These yielded values of 0.97 for total absorptance (AM2 spectrum) and 0.08 (100°C) for the thermal emittance on a basis of light Watts-type nickel. Other nickel undercoatings which were investigated produced less satisfactory results.Both the thermal stability of the plating up to temperatures of 400°C and the dependence of its IR emittance on temperature were investigated. The tubes coated in the way described have a uniform, matt-black appearance and the thermo-optical properties are constant along their whole length and round their whole circumference.  相似文献   
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