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This proceeding presents experiments demonstrating that BioLPTM, Biological Laser Printing, can be used to rapidly and accurately print individual cells as well as patterns of cells in three dimensions. Human osteosarcoma cells were deposited into a biopolymer matrix, and after twenty-four hours of incubation, the printed cells remained viable and had multiplied. Multiple layers of human osteosarcoma cells were transferred into a MatrigelTM substrate, producing a three-dimensional cellular construct. Live/dead assays were performed, demonstrating that greater than 95% of the cells were viable after the being printed into the biopolymer. The ability to selectively print individual cells has potential benefits for cell selection studies and genomics and proteomics research. In addition, this technique could enable layers of tissue scaffolding to be seeded with cells at exceedingly high precision and resolution. PACS 87.15.La; 87.18.Hf; 87.50.Hj  相似文献   
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Heavy metal pollution is a major environmental problem in the modern world due to increasing human activities. Zinc is an essential element involved in a wide variety of cellular processes. However, it becomes toxic when elevated concentrations are introduced into the environment. The goal of the present study is to investigate the effect of zinc exposure on the biochemical contents of the muscle tissues of freshwater species Labeo rohita using Fourier transform infrared (FT-IR) spectroscopy. Since the muscle constitutes the greatest mass of the fish that is consumed, the present study has paid particular attention to muscle component. The result reveals that the zinc exposure causes significant changes in the biochemical contents of the L. rohita muscle tissues. In addition, it causes an alteration in the protein secondary structures by decreasing the α-helix and increasing the β-sheet contents of muscle tissues. Further, it has been observed that the administration of chelating agent D-penicillamine improves the protein and lipid contents in the muscle tissues compared to zinc exposed tissues. This result shows that D-penicillamine is the effective chelator of zinc in reducing the body burden of L. rohita fingerlings.  相似文献   
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The C2-symmetric vinyl sulfoxide, trans-2-methylene-1,3-dithiolane 1,3-dioxide, was found to react with a range of 3-oxidopyridinium betaines (bearing different substituents on nitrogen) in high yield and with total diastereoselectivity. A 2.3:1 mixture of regioisomers was formed with all of the 3-oxidopyridinium betaines but the ratio was found to change over prolonged periods of time due to reversibility of the minor regioisomer. 3-Oxidopyridinium betaines bearing methyl substituents at either the 2- or 6-position were also tested in the cycloaddition process. Improved regioselectivity (8:1) and again high diastereoselectivity were observed with the betaine having an additional substituent at the 2-position, but with betaines having a substituent in the 6-position although high regioselectivity was observed (9.9:1), the major isomer was formed with low diastereoselectivity (5.5:4.4). The origin of the regio- and diastereo-selectivity with all the betaines is discussed. Finally, the C2-symmetric vinyl sulfoxide, trans-2-methylene-1,3-dithiolane 1,3-dioxide was reacted with an oxidopyrylium betaine in moderate yield. Good regioselectivity and moderate diastereoselectivity were observed.  相似文献   
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COMPOSITION OPERATOR ON BERS-TYPE SPACES   总被引:2,自引:0,他引:2  
Necessary and sufficient conditions are established for a composition operator C f = fo to be bounded or compact on the Bers-type space Ha and the little Bers-type space Ha The boundedness and compactness of the composition operator C on A() are characterized, which generalize the case of C on Ha.  相似文献   
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S Bose  PL Knight  MB Plenio  V Vedral 《Pramana》2001,56(2-3):383-391
We present a rare example of a decay mechanism playing a constructive role in quantum information processing. We show how the state of an atom trapped in a cavity can be teleported to a second atom trapped in a distant cavity by the joint detection of photon leakage from the cavities. The scheme, which is probabilistic, requires only a single three level atom in a cavity. We also show how this scheme can be modified to a teleportation with insurance.  相似文献   
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This article presents the changes in the thermal properties of the control and titanium dioxide (TiO2), both nano and bulk exposed Zebrafish bones by using thermo analytical techniques. The result shows that the mass loss due to the thermal decomposition occurs in three distinct steps due to loss of water, organic and inorganic materials. The titanium dioxide exposed bones present a different thermal behaviour compared to the control bones. The residue masses are found to be increased due to titanium dioxide exposure. In particular, nano titanium dioxide exposure increases the residue mass level significantly (three fold) when compared to titanium dioxide bulk exposure. These thermal characteristics can be used as a qualitative method to check the metal oxide intoxication in biological samples.  相似文献   
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We compare the results of small angle neutron scattering on the flux line lattice (FLL) obtained in the borocarbide superconductor LuNi2B2C with the applied field along the c- and a-axes. For H‖c the temperature dependence of the FLL structural phase transition from square to hexagonal symmetry was investigated. Above 10 K the transition onset field. H 2(T), rises sharply, bending away from H c2(T) in contradiction to theoretical predictions of the two merging. For H‖a a first order FLL reorientation transition is observed at H tr=3–3.5 kOe. Below H tr the FLL nearest neighbor direction is parallel to the b-axis, and above H tr to the c-axis. This transition cannot be explained using nonlocal corrections to the London model.  相似文献   
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