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41.
42.
Jagannathan Ramesh Ahmad Salman Shaul Mordechai Shmuel Argov Jed Goldstein Igor Sinelnikov Shlomo Walfisch Hugo Guterman 《Subsurface Sensing Technologies and Applications》2001,2(2):99-117
Fourier-Transform Infrared Spectroscopy (FTIR) employs a unique approach tooptical diagnosis of tissue pathology based on the characteristic molecularvibrational spectra of the tissue. The biomolecular changes in the cellularand sub-cellular levels developing in abnormal tissue, including a majorityof cancer forms, manifest themselves in different optical signatures, whichcan be detected in infrared microspectroscopy. This report has two parts. Inthe first part, we report studies on normal, premalignant (polyp) andmalignant human colonic tissues from three patients with different stages ofmalignancy. Our method is based on microscopic infrared study (FTIR-microscopy)of thin tissue specimens and a direct comparison with traditional histopathologicalanalysis, which serves as a gold reference. The limited dataavailable showed normal colonic tissue has a stronger absorption thanpolypoid tumor and cancerous types over a wide region in a total of 100measurements. Detailed analysis showed that there is a significant decreasein total carbohydrate, phosphate and possibly creatine contents for polyp andcancerous tissue types in comparison to the controls. The same trend is maintainedin seven other patients studied. The second part consists of an analysis showingthe influence of various independent factors such as age, sex and grade of malignancy. Ourpreliminary results suggest that among the above three factors, age and gradeof malignancy have significant effect on the metabolites level, but sex has onlyminor effect on the measured spectra. Initial results on Linear DiscriminantAnalysis (LDA) showed good classification between normal and malignant cellsof human colonic tissues. 相似文献
43.
Escherichia coli introduced into the hydroponic growing medium of maize plants was detected 48 h later in the shoot. Decapitation of root tips or severing of the plant root system at the root-shoot junction enhanced bacterial internalization. The density of the bacteria in shoots of plants with damaged roots or removed root systems was 27.8 and 23.9 times higher than that in plants with intact roots, respectively. The concentration of viable cells in the hydroponic solution decreased over time from 9.3 x 10(6) CFU/ml at the time of inoculation to 8.5 x 10(1) CFU/ml 4 days thereafter. The number of E. coli cells associated with the roots also decreased with time, but a significant decline appeared only at 4 days postinoculation. At the time of sampling for E. coli presence in the shoot, 10(2) CFU/ml was present in the nutrient solution and 8 x 10(3) CFU/g was associated with the roots. The present study is the first to demonstrate internalization of E. coli via the root in a monocotyledonous plant. 相似文献
44.
大地电磁测深的拟地震解释法 总被引:5,自引:2,他引:3
在水平层状介质条件下,如果把地层划分为电磁波或弹性波在其中的双程旅行时都相等的“微层”,则大地电磁场和弹性波的位移场的反射函数无论是在表现形式上,或是在物理意义上都是十分相似的。这样的话,大地电磁测深法也可以象地震反射法一样画出“时间剖面”进行地质解释。这种方法还可推广到二维大地电磁测深和电测深资料的解释。通过对二层、三层和四层断面的理论模型试算,说明此方法是可行的。但是,无论是在理论上,还是在实践中都有许多值得研究的问题,例如在MT中反射函数的精度受观测精度及计算方法的影响。因此,研究新的观测方法和计算方法就显得很有必要。再如怎样把地震资料处理中一些消除干扰和提高分辨率的措施用于MT法。 相似文献
45.
Ortal Danino Hugo E. Gottlieb Shlomo Grossman Margalit Bergman 《Food research international (Ottawa, Ont.)》2009,42(9):1273-1280
Inula viscosa is a perennial herbaceous plant used topically in folk medicine as an anti-scabies, anti-inflammatory, and wound-healing agent. We examined the antioxidant activity of the methanolic extract of I. viscosa. We isolated and identified several polyphenolic antioxidants from I. viscosa leaves and focused on 1,3-dicaffeoylquinic acid (1,3-diCQA). Antioxidant activity was measured using ABTS and DPPH assays, which measure antioxidant activity. The concentrations of 1,3-diCQA required for the inhibition of oxidation were lower than those required by other known antioxidants. 1,3-diCQA inhibited oxidative damage caused by various factors, including FeSO4 and AAPH (2,2′-azobis(2-amidinopropane) dehydrochloride). Antioxidant activity can also be detected by the ability of a compound to scavenge reactive oxygen species (ROS). 1,3-diCQA was found to scavenge hydroxyl radical and superoxide radicals, as measured by electron spin resonance (ESR). These data demonstrate that 1,3-diCQA exhibits antioxidant properties, probably through the involvement of a direct scavenging effect on several free radicals. 相似文献
46.
Tailored compositions of transverse modes provided by mathematical generating functions are exploited for the synthesis of multimode laser beams in free space. We show that analytical equations which are available for the generating functions provide physical insight into modal phase and power balance in multimode coherent light beams. Multimode coherent beams were created by methods of diffractive optics implementing the generating functions. Experimental and computer simulated results demonstrate a good match. 相似文献
47.
The reduction of semantic priming following letter search of the prime suggests that semantic activation can be blocked if attention is allocated to the letter level during word processing. Is this true even for the very fast-acting component of semantic activation? To test this, the authors explored semantic priming of lexical decision at stimulus onset asynchronies (SOAs) of either 200 or 1000 ms. Following semantic prime processing, priming occurred at both SOAs. In contrast, no priming occurred at the long SOA following letter-level processing. Of greatest interest, at the short SOA there was priming following the less demanding consonant/vowel task but not following the more attention-demanding letter search task. Hence, semantic activation can occur even when attention is directed to the letter level, provided there are sufficient resources to support this activation. The authors conclude that the default setting during word recognition is for fast-acting activation of the semantic system. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
Water remediation by micelle-clay system: case study for tetracycline and sulfonamide antibiotics 总被引:3,自引:0,他引:3
Removal of tetracycline and sulfonamide antibiotics from water by micelles pre-adsorbed on montmorillonite was studied. Micelles of benzyldimethylhexadecylammonium (BDMHDA) were used. Batch experiments demonstrated that the micelle-clay complexes (1% w/w) removed 96-99.9% of antibiotics from their water solutions containing from 5 to 50 mg/L of pharmaceuticals. Column filters (25 cm) made of a mixture of quartz sand and BDMHDA micelle-clay complex at 100:1 w/w ratio removed 94-99.9% of above pharmaceuticals from initial solutions containing 10mg/L and 89% of sulfamethizole from an initial solution containing 10 microg/L of this antibiotic. These filters were also very efficient in the removal of antibiotics in the presence of dissolved soil organic matter removing 89-99% of tetracycline and sulfamethizol from initial solutions containing 10 mg/L of antibiotic in the presence of 8 mg/L of humic acid, or 9 mg/L of fulvic acid. These data indicate that micelle-clay complexes are very efficient for water purification from tetracycline and sulfonamide antibiotics. 相似文献
49.
Melamed Samuel; Shirom Arie; Toker Sharon; Berliner Shlomo; Shapira Itzhak 《Canadian Metallurgical Quarterly》2006,132(3):327
Burnout is characterized by emotional exhaustion, physical fatigue, and cognitive weariness, resulting from prolonged exposure to work-related stress. The authors review the accumulated evidence suggesting that burnout and the related concept of vital exhaustion are associated with increased risk of cardiovascular disease and cardiovascular-related events. The authors present evidence supporting several potential mechanisms linking burnout with ill health, including the metabolic syndrome, dysregulation of the hypothalamic-pituitary-adrenal axis along with sympathetic nervous system activation, sleep disturbances, systemic inflammation, impaired immunity functions, blood coagulation and fibrinolysis, and poor health behaviors. The association of burnout and vital exhaustion with these disease mediators suggests that their impact on health may be more extensive than currently indicated. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
Summary Analyzing distributed protocols in various models often involves a careful analysis of the set ofadmissible runs, for which the protocols should behave correctly. In particular, the admissible runs assumed by at-resilient protocol are runs which are fair for all but at mostt processors. In this paper we defineclosed sets of runs, and suggest a technique to prove impossibility results fort-resilient protocols, by restricting the corresponding sets of admissible runs to smaller sets, which are closed, as follows: For each protocolPR and for each initial configurationc, the set of admissible runs ofPR which start fromc defines a tree in a natural way: the root of the tree is the empty run, and each vertex in it denotes a finite prefix of an admissible run; a vertexu in the tree has a sonv iffv is also a prefix of an admissible run, which extendsu by one atomic step.The tree of admissible runs described above may contain infinite paths which are not admissible runs. A set of admissible runs isclosed if for every possible initial configurationc, each path in the tree of admissible runs starting fromc is also an admissible run. Closed sets of runs have the simple combinatorial structure of the set of paths of an infinite tree, which makes them easier to analyze. We introduce a unified method for constructing closed sets of admissible runs by using a model-independent construction of closedschedulers, and then mapping these schedulers to closed sets of runs. We use this construction to provide a unified proof of impossibility of consensus protocols.
Ronit Lubitch received her B.Sc. degree in Mathematics and Computer Science from Tel Aviv University in 1989, and her Master degree in Computer Science from the Technion, in 1993. From 1992 she is working in Graffiti Software Industries, which expertise in the design and development of advanced photo realistic rendering, and animation software systems.
Shlomo Moran received his B.Sc. and Ph.D. degrees in Mathematics from the Technion in 1975 and 1979 resp. In 1979–1981 he was at the University of Minnesota as a visiting research specialist. In 1981 he joined the Computer Science Department at the Technion, where he is now a full professor. In 1985–1986 he visited at IBM T.J. Watson Research Center. In 1992–1993 he visited at AT&T Bell Laboratories and in Centrum voor Wiskunde en Informatica, Amsterdam. His research interests include distributed computing, Combinatorics and Graph Theory, and Complexity Theory.A preliminary extended version of this paper appeared in the Proceedings of 6-th International Workshop on Distributed Algorithms, Haifa, November 1992This work was supported in part by the Technion V.P.R. fund. Part of this research was conducted while this author was visiting at AT&T Bell Labs at Murray Hill and at CWI, Amsterdam 相似文献