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101.
Evidence for the existence of a novel bacteriological system has been obtained from osmotically lysed and filtered human blood (membrane filters with a pore size of 0.22 micronm) placed in special culture media. These blood filtrates gave rise to ordinary bacteria for 71% of the blood specimens processed from diseased humans and for 7% of those from supposedly normal humans. Morphologically, the bacteria resembled streptococcal, staphylococcal, and gram-positive filamentous (cocco-bacillary) forms. Prior to the appearance of bacteria in the media, large and small "dense bodies" were microscopically observed but disappeared when ordinary bacteria were apparent, Cultures of of unlysed blood as conventionally performed were negative. These organisms may represent an adaptation of certain bacteria to life in the blood. 相似文献
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A package for analysing two-dimensional finite fringe interferograms is described. Through a combination of automatic and interactive routines, an interferogram can be processed to extract the phase shift imparted on the recording light by a transparent object. The package consists of routines to condition and pad the original image for Fourier transform analysis, to filter the image and obtain the phase, to unwrap the phase, and to remove the background phase ramp. A sample image recorded using holographic interferometry is successfully analysed.Program summaryProgram title: FRINGECatalogue identifier: AEMM_v1_0Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEMM_v1_0.htmlProgram obtainable from: CPC Program Library, Queen’s University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 134006No. of bytes in distributed program, including test data, etc.: 4029801Distribution format: tar.gzProgramming language: Java.Computer: Personal Computers.Operating system: Mac OS X, Windows XP, Linux and any other system that can run Java Jar files.RAM: 1GB recommendedClassification: 18.Nature of problem: A standalone multi-platform program to perform analysis of finite fringe interferograms.Solution method: Fourier filtering approach with phase unwrapping and background subtraction.Restrictions: Designed to analyse square images.Running time: Interactive processing takes several minutes. Minimal cpu time. 相似文献
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Sergey A. Alexandrov P. Meredith T. J. McIntyre A. V. Zvyagin 《International journal of imaging systems and technology》2004,14(6):253-258
We present an application of digital Fourier holography for selective imaging of scatterers with different sizes in turbid media such as biological tissues. A combination of Fourier holography and high‐resolution digital recording, digital Fourier microscopy (DFM) permits crucial flexibility in applying filtering to highlight scatterers of interest in the tissue. The high‐resolution digital hologram is a result of the collation of Fourier holographic frames to form a large‐size composite hologram. It is expected that DFM has an improved signal‐to‐noise ratio as compared to conventional direct digital imaging, e.g., phase microscopy, as applied to imaging of small‐size objects. The demonstration of the Fourier filtering capacity of DFM using a biological phantom represents the main focus of this article. © 2005 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 14, 253–258, 2004; Published online inWiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.20031 相似文献
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The use of two-dimensional Nuclear Magnetic Resonance (NMR) spectroscopy as applied to studies of starch, starch products and glycogen is reported. The use of both homonuclear correlation (COSY, relay-COSY and HOHAHA) and heteronuclear correlation (HMQC, HETCOR) experiments is discussed. This approach makes it possible to obtain complete assignments of the proton NMR spectra of these polysaccharides. This is not possible from 1-D spectra due to excessive overlap of the non-anomeric proton signals. The resulting assignments are useful in obtaining structural information regarding starch and related products. Moreover, the greater inherent resolution of the two-dimensional spectra can reveal the presence of low molecular weight carbohydrates (glucose, maltose etc.) in dextrin samples, thus providing information about carbohydrate composition. 相似文献
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Cyril Caminade Jolyon M. Medlock Els Ducheyne K. Marie McIntyre Steve Leach Matthew Baylis Andrew P. Morse 《Journal of the Royal Society Interface》2012,9(75):2708-2717
The Asian tiger mosquito (Aedes albopictus) is an invasive species that has the potential to transmit infectious diseases such as dengue and chikungunya fever. Using high-resolution observations and regional climate model scenarios for the future, we investigated the suitability of Europe for A. albopictus using both recent climate and future climate conditions. The results show that southern France, northern Italy, the northern coast of Spain, the eastern coast of the Adriatic Sea and western Turkey were climatically suitable areas for the establishment of the mosquito during the 1960–1980s. Over the last two decades, climate conditions have become more suitable for the mosquito over central northwestern Europe (Benelux, western Germany) and the Balkans, while they have become less suitable over southern Spain. Similar trends are likely in the future, with an increased risk simulated over northern Europe and slightly decreased risk over southern Europe. These distribution shifts are related to wetter and warmer conditions favouring the overwintering of A. albopictus in the north, and drier and warmer summers that might limit its southward expansion. 相似文献
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