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951.
952.
The life sciences have sprouted several popular and successful OMICS technologies that span all levels of biological information transfer. Ever since the start of the Human Genome Project, the then revolutionary idea to make all resulting data publicly available has been central to all of the efforts across OMICS technologies. As a result, a great variety of publicly available data repositories and resources is currently available to the research community. This widespread availability of data does come at the price of increased confusion on the part of the users, especially for those that see the OMICS technologies as tools to help unravel a larger biological or clinical question. We therefore provide a comprehensive overview of the available resources across OMICS fields, with a special emphasis on those databases that are relevant to the study of proteins. Additionally, we also describe various integrative systems that have been established, and highlight new developments in the field that can revolutionize the way in which live data integration is achieved over the internet.  相似文献   
953.
Multicomponent silicate glasses are ubiquitous in modern society as evidenced by their inclusion in applications ranging from building materials and microelectronics to biomedical implants. Of particular interest in this study is the interface between multicomponent silicate glasses and adhesive polymers. These polymeric systems often possess a variety of different organic functional groups. In this study, we selected acetic acid as a probe molecule representative of the carboxylic acid functional group found in many adhesives. We have used Fourier transform infrared spectroscopy (FT-IR) and NMR to study the interaction of acetic acid with the surface of sodium aluminoborosilicate continuous glass fibers. Methods were developed that enable analyses to be carried out without damaging or altering the pristine as drawn fiber surface. While dosing the surface of fumed silica with acetic acid resulted in the formation of silyl ester groups, analogous dosing of sodium aluminoborosilicate glass fibers resulted in the formation of carboxylate species, principally coordinated to sodium, while silyl ester groups were not observed.  相似文献   
954.
Martin GC  Mueller CJ  Lee CF 《Applied optics》2006,45(9):2089-2100
A two-photon nitric oxide (NO) laser-induced fluorescence (LIF) technique was developed and applied to study in-cylinder diesel combustion. The technique prevents many problems associated with in-cylinder, single-photon NO planar-laser-induced fluorescence measurements, including fluorescence interference from the Schumann-Runge bands of hot O2, absorption of a UV excitation beam by in-cylinder gases, and difficulty in rejecting scattered laser light while simultaneously attempting to maximize fluorescence signal collection. Verification that the signal resulted from NO was provided by tuning of the laser to a vibrational off-resonance wavelength that showed near-zero signal levels, which resulted from either fluorescence or interference at in-cylinder pressures of as much as 20 bar. The two-photon NO LIF signal showed good qualitative agreement with NO exhaust-gas measurements obtained over a wide range of engine loads.  相似文献   
955.
The emerging field of spintronics explores the many possibilities offered by the prospect of using the spin of the electrons for fast, nanosized electronic devices. The effect of magnetization acting on a current is the essence of giant or tunnel magnetoresistance. Although such spintronics effects already find technological applications, much of the underlying physics remains to be explored. The aim of this article is to demonstrate the importance of spin mixing in metallic nanostructures. Here we show that magnetic clusters embedded in a metallic matrix exhibit a giant magnetic response of more than 500% at low temperature, using a recently developed thermoelectric measurement. This method eliminates the dominating resistivity component of the magnetic response and thus reveals an intrinsic spin-dependent process: the conduction-electron spin precession about the exchange field as the electron crosses the clusters, giving rise to a spin-mixing mechanism with strong field dependence. This effect appears sensibly only in the smallest clusters, that is, at the level of less than 100 atoms per cluster.  相似文献   
956.
957.
Bioaerosol mass spectrometry is being developed to analyze and identify biological aerosols in real time. Mass spectra of individual Bacillus endospores were measured with a bipolar aerosol time-of-flight mass spectrometer in which molecular desorption and ionization were produced using a single laser pulse from a Q-switched, frequency-quadrupled Nd:YAG laser that was modified to have an approximately flattop profile. The flattened laser profile allowed the minimum fluence required to desorb and ionize significant numbers of ions from single aerosol particles to be determined. For Bacillus spores, this threshold had a mean value of approximately 1 nJ/microm(2) (0.1 J/cm(2)). Thresholds for individual spores, however, could apparently deviate by 20% or more from the mean. Threshold distributions for clumps of MS2 bacteriophage and bovine serum albumin were subsequently determined. Finally, the flattened profile was observed to increase the reproducibility of single-spore mass spectra. This is consistent with the general conclusions of our earlier paper on the fluence dependence of single-spore mass spectra and is particularly significant because it is expected to enable more robust differentiation and identification of single bioaerosol particles.  相似文献   
958.
Seward GH  Mueller PF 《Applied optics》1997,36(22):5363-5371
A microlens array structure that prevents automated photocopying is presented. This copy defeat laminate (CDL) employs a cylindrical lens array structure in conjunction with a mask pattern to prevent at-normal viewing of the document. Image brightness perceived by the human eye is reviewed as well as basic radiometry. Equations for Lambertian and CDL image brightness are derived. The brighter-than-white appearance of a CDL covered document is explained. Designs for the full-page-defeat and full-page-view versions of the CDL are presented.  相似文献   
959.
Nanocomposite glasses containing metallic nanoparticles can be microstructured by electric‐field assisted dissolution of the embedded particles. As reported by Graener and co‐workers on p. 2983, any pattern of the electrode—down to the nanoscale—can be transferred onto the nanocomposite glass, giving 2D metallodielectric microstructures. The cover image shows as the background a regular array of squares with 2 μm periodicity produced using macroporous silicon as an electrode. The insets show the base material, the electrode, a representation of the dissolution process, and an enlarged view of the remaining silver nanoparticles.  相似文献   
960.
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