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11.
Klaudija Carovi-Stanko Sandi Orli Olivera Politeo Frane Striki Ivan Kolak Mladen Milos Zlatko Satovic 《Food chemistry》2010,119(1):196-201
GC/MS was used to identify compounds of essential oils from seven Ocimum taxa (O. americanum L., O. basilicum L., O. campechianum Mill., O. x citriodorum Vis., O. kilimandscharicum Baker ex Gürke and three botanical varieties and cultivars of Ocimum basilicum L.: ‘Genovese’, var. difforme and var. purpurascens). Preliminary screening of their antibacterial activity was done against a number of common pathogens (Enterococcus faecalis, Enterococus faecium, Escherichia coli 0157:H7, Listeria monocytogenes, Listeria ivanovii, Proteus vulgaris, Staphylococcus aureus, Staphylococcus epidermis) using the filter paper disc agar diffusion technique, while further analyses were done by modification of the disc diffusion method. A broad variation in the antibacterial properties of investigated essential oils was observed. E. coli 0157:H7 was inhibited by O. basilicum ‘Genovese’ essential oil, while Ocimum americanum and Ocimum x citriodorum essential oils were the most effective against Enterococcus faecalis, Enterococcus faecium, P. vulgaris, S. aureus and S. epidermis. 相似文献
12.
Starkey JA Mechref Y Byun CK Steinmetz R Fuqua JS Pescovitz OH Novotny MV 《Analytical chemistry》2002,74(23):5998-6005
Capillary electrochromatography using a specialty monolithic matrix was utilized in developing a rapid and highly efficient separation of isoflavones in biological materials. Without a preconcentration technique, it is relatively easy to reach ppm-ppb concentrations of these compounds in soy-based foods and verify them structurally using a photodiode array detector. With on-column preconcentration, we were able to measure low-ppb levels in human serum. Using blood samples from human volunteers, whose diet was supplemented by a soy-based product, the method has been validated for high-throughput screening of isoflavones in clinical studies. 相似文献
13.
We report on mechanization of a correctness proof of a string-preprocessing algorithm. This preprocessing algorithm is employed
in Boyer-Moore’s pattern matching algorithm. The mechanization is carried out using the PVS system. The correctness proof
being mechanized has been formulated in Linear Time Temporal Logic. It consists of fourteen lemmata which are related to safety
properties and two additional lemmata dealing with liveness properties. The entire mechanization of the safety and liveness
parts has been completed. Several small errors and omissions were found in the handwritten proof and corrected. Yet, the manual
correctness proof of the string-preprocessing algorithm was found to satisfy the usual mathematical validity. We conclude
that the string-preprocessing algorithm in Boyer-Moore’s pattern matching algorithm, corrected a number of times because of
flaws, does not contain any more undiscovered errors.
An extended abstract of this work appears in the Proceedings of the 8th IEEE International Conference on Engineering of Complex Computer Systems (ICECCS ‘02). 相似文献
14.
A sample deposition device has been constructed and optimized for interfacing CEC and capillary LC columns to MALDI mass spectrometry. For CEC analysis, the device is composed of an inlet buffer reservoir and an outlet buffer reservoir connected to a matrix reservoir through a connection sleeve. The matrix reservoir is connected to a deposition capillary via another connection sleeve. CEC eluent is transported to the matrix reservoir via a capillary that is connected to the deposition capillary by the connection sleeve inside the matrix reservoir. This connection sleeve also acts as a mixing chamber, allowing the CEC eluent to be mixed with matrix prior to deposition. Complex glycan mixtures can be separated by CEC using hydrophilic-phase monolithic columns, with capillary eluent being deposited on a standard MALDI plate along with a suitable matrix solution. Thousands of discrete, highly homogeneous dots can be generated for a subsequent mass spectrometric analysis. With minor modifications, this device is also applicable to capillary LC of peptides using gradient elution. In this configuration, the outlet of the LC column is connected to a deposition capillary inside a matrix reservoir through a connection sleeve that allows mixing of the LC effluent with an appropriate matrix. The device has been evaluated with the tryptic digests of proteins. 相似文献
15.
Evaluated the effects of separation-relevant play on separation anxiety in young children to test the hypothesis that play can reduce anxiety. Ss were 32 males and 32 females, aged 2–6 yrs, rated by their teachers as anxious about separation from parents. Ss were assigned to 1 of 3 thematic-play conditions (free play, directed play, and modeling) and a 4th nonthematic-play (control) condition, so that pretreatment anxiety levels were approximately equivalent across conditions. All 3 experimental conditions were associated with lower posttest anxiety scores on a speech-disturbance measure but not on teacher ratings. Higher quality of play (mastery) was associated with lower posttest anxiety scores. Implications are discussed for play therapy, separation-anxiety treatments, and the use of speech disturbance as a measure of anxiety in young children. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
16.
Our goal is to design algorithms that give a linearity measure for planar point sets. There is no explicit discussion on linearity in literature, although some existing shape measures may be adapted. We are interested in linearity measures which are invariant to rotation, scaling, and translation. These linearity measures should also be calculated very quickly and be resistant to protrusions in the data set. The measures of eccentricity and contour smoothness were adapted from literature, the other five being triangle heights, triangle perimeters, rotation correlation, average orientations, and ellipse axis ratio. The algorithms are tested on 30 sample curves and the results are compared against the linear classifications of these curves by human subjects. It is found that humans and computers typically easily identify sets of points that are clearly linear, and sets of points that are clearly not linear. They have trouble measuring sets of points which are in the gray area in-between. Although they appear to be conceptually very different approaches, we prove, theoretically and experimentally, that eccentricity and rotation correlation yield exactly the same linearity measurements. They however provide results which are furthest from human measurements. The average orientations method provides the closest results to human perception, while the other algorithms proved themselves to be very competitive. 相似文献
17.
Slavica Siler-marinkovic Ljiljana Mojovic Violeta Davinic Branko Bugarski 《Drug development and industrial pharmacy》1997,23(5):483-488
Liposome are promising drug carrier systems being developed. Their successful use in the treatment of several diseases demonstrates that a solid rationale for clinical development of liposomes as antimicrobial drug carriers can be established. There are a number of potential drug candidates for liposome encapsulation. The involvement of several biotechnology companies has culminated in the design and licensing of formulations for the treatment of certain microbial infections and cancers. Understanding of liposome behavior in the body and of the physicochemical mechanisms involved in the interaction of liposome, drug, and cellular targets is essential for their future applications. 相似文献
18.
19.
Nikola R. Slavkovic Dragan S. Milutinovic Milos M. Glavonjic 《The International Journal of Advanced Manufacturing Technology》2014,70(9-12):2083-2096
Industrial robots are promising cost-effective and flexible alternatives for multi-axis milling applications in machining of complex parts of light materials with lower tolerances, having freeform surfaces. As it is well-known, the poor accuracy, stiffness, and the complexity of programming are the most important limiting factors for wider adoption of robotic machining in machine shops. The paper presents the developed method for off-line compensation of machining robot tool tip static displacements as a dominant part of cutting force-induced errors. The developed method is based on modification of programmed trajectory in G-code. Off-line modification of programmed trajectory is performed according to the predicted static tool tip displacements calculated based on developed robot compliance model and cutting forces predicted by mechanistic model. The obtained experimental results show the relevance of developed method since the machining errors could be significantly reduced. This allows the desired accuracy of robot machining to converge towards nominal specifications. 相似文献
20.
Viorel Badescu Christian A. GueymardMadalina Baciu Alexandru Dumitrescu Flavius IacobescuIoan Milos Costel Rada 《Renewable & Sustainable Energy Reviews》2012,16(3):1636-1656
Fifty-four broad band models for computation of global and diffuse irradiance on horizontal surface are shortly presented and tested. The input data for these models consist of surface meteorological data, atmospheric column integrated data and data derived from satellite measurements. The testing procedure is performed for two meteorological stations in Romania (South-Eastern Europe). The testing procedure consists of forty-two stages intended to provide information about the sensitivity of the models to various sets of input data. There is no model to be ranked “the best” for all sets of input data. Very simple models as well as more complex models may belong to the category of “good models”. The best models for solar global radiation computation are, on equal-footing, ESRA3, Ineichen, METSTAT and REST2 (version 81). The second best models are, on equal-footing, Bird, CEM and Paulescu & Schlett. The best models for solar diffuse radiation computation are, on equal-footing, ASHRAE2005 and King. The second best model is MAC model. The best models for computation of both global and diffuse radiation are, on equal-footing, ASHRAE 1972, Biga, Ineichen and REST2 (version 81). The second best is Paulescu & Schlett model. 相似文献