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21.
New solid and liquid media have been developed for the cultivation of a group of slow-developing pediococci, isolated from brewery products, that have previously proved difficult to cultivate. These media also formed a suitable basis for the production of special media for identification and classification of such pediococci. A physiological and biochemical study indicated that the strains investigated are closely akin to a group of pediococci which by other workers are classified as Pediococcus damnosus. 相似文献
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23.
Molecular dynamics of the 5-HT1a receptor and ligands 总被引:2,自引:0,他引:2
Sylte Ingebrigt; Edvardsen Oyvind; Dahl Svein G. 《Protein engineering, design & selection : PEDS》1993,6(7):691-700
A 3-D model of the human 5-HT1a receptor was constructed fromits amino acid sequence by computer graphics techniques, molecularmechanics calculations and molecular dynamics simulations. Themodel has seven -helical membrane spanning segments, which forma central core containing a putative ligand binding site. Electrostaticpotentials 1.4 Å outside the water accessible surfacewere mainly negative on the synaptic side of the receptor modeland at the postulated ligand binding site, and positive in thecytoplasmic domains. The negative electrostatic potentials aroundthe synaptic domains indicate that positively charged ligandsare attracted to the receptor by electrostatic forces. Moleculardynamics simulations of the receptor model with serotonin, ipsapirone,R()-methiothepin or S(+)- methiothepin in the centralcore suggested that up to 22 different amino acid residues mayform a ligand binding pocket, and contribute to the specificityof ligand recognition and binding. 相似文献
24.
Heia K Sivertsen AH Stormo SK Elvevoll E Wold JP Nilsen H 《Journal of food science》2007,72(1):E011-E015
ABSTRACT: A promising method for detection of parasites in whitefish fillets has been developed. By use of imaging spectroscopy it is possible to record both spectral and spatial information from an object. In this work it is shown that by applying a white light transmission setup and imaging spectroscopy to cod ( Gadus morhua ) fillets, it is possible to make spectral images containing information to differentiate between fish muscle and parasites. The spectral images are analyzed by discriminant partial least square regression as well as image-filtering techniques. The method identifies parasites on the surface of the fillets as well as embedded parasites. One parasite was detected at 0.8 cm below the fillet surface, which is 2 to 3 mm deeper than what can be found by manual inspection of fish fillets. The method is nonintrusive and should thus be feasible for industrial purposes. 相似文献
25.
Automatic detection of oil spills in ERS SAR images 总被引:4,自引:0,他引:4
Solberg A.H.S. Storvik G. Solberg R. Volden E. 《Geoscience and Remote Sensing, IEEE Transactions on》1999,37(4):1916-1924
The authors present algorithms for the automatic detection of oil spills in SAR images. The developed framework consists of first detecting dark spots in the image, then computing a set of features for each dark spot, before the spot is classified as either an oil slick or a “lookalike” (other oceanographic phenomena which resemble oil slicks). The classification rule is constructed by combining statistical modeling with a rule-based approach. Prior knowledge about the higher probability for the presence of oil slicks around ships and oil platforms is incorporated into the model. In addition, knowledge about the external conditions like wind level and slick surroundings are taken into account. The presented algorithms are tested on 84 SAR images. The algorithm can discriminate between oil slicks and lookalikes with high accuracy, 94% of the oil slicks and 99% of the lookalikes were correctly classified 相似文献
26.
Munger Margaret P.; Solberg Jennifer L.; Horrocks Kristoffer K.; Preston Andrew S. 《Canadian Metallurgical Quarterly》1999,25(1):157
Representational momentum is a positive memory distortion for an object's final position following the presentation of an implied event (J. J. Freyd, 1987). Positive memory distortions occur when observers accept test positions beyond the final presented position, or forward along the implied trajectory, as the same more readily than positions behind the final position. Four experiments explored implied events depicting rotations about various depth axes in shaded and silhouette conditions. Positive memory distortions were observed for all depth rotations under certain shading conditions, with some differences in the size of the distortion between axes. No directional effects (e.g., right vs. left) were observed. The overall positive memory distortions observed for depth rotations contrasted with the negative distortions previously observed for translation motion in depth (T. L. Hubbard, 1995b). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
27.
Svein M Eilertsen Ivar Schjelderup Svein D Mathiesen 《Journal of the science of food and agriculture》2000,80(3):329-334
Dry matter (DM) production and nutritional quality of plants were recorded on an old meadow before, during and after it was grazed by reindeer (Rangifer tarandus tarandus; 15 reindeer ha−1) in the spring of 1996 and 1997 in northern Norway. Mean herbage harvest after 54 and 50 days of growth including 25 and 24 days of reindeer grazing was 1217 ± 320 kg DM ha−1 in 1996 and 2297 ± 495 kg DM ha−1 in 1997 respectively. On ungrazed old meadow, in contrast (P < 0.05), mean herbage harvest after 54 and 50 days of growth was 4159 ± 1164 kg DM ha−1 in 1996 and 3791 ± 275 kg DM ha−1 in 1997 respectively. In 1997, mean herbage harvest after 50 days of growth including 7 days of grazing by reindeer was as high as 3441 ± 180 kg DM ha−1 (P > 0.05). Crude protein content (% of DM) was 25% early in the growing season in both 1996 and 1997. After 54 and 50 days of growth including 25 and 24 days of reindeer grazing, crude protein content was about 17% of DM in both 1996 and 1997 respectively, compared with about 12% of DM in ungrazed old meadow in both years. In 1997, crude protein content was 13.3% of DM after 50 days of growth including 7 days of reindeer grazing. The grazed and ungrazed old meadow contained about 20% (of DM) water‐soluble carbohydrates throughout the summer in both years. Mean plant cell wall content in ungrazed plants harvested after about 50 days was higher (51.5 and 49.1% of DM; P > 0.05) compared with plant cell wall content in grazed meadow (49.0 and 46.4% of DM) in 1996 and 1997 respectively. In vitro dry matter digestibility (%) of herbage harvest using rumen fluid from domestic ruminants was about 10% higher (73.4 ± 0.30 and 75.7 ± 0.28) in samples from grazed meadow compared with ungrazed meadow (66.2 ± 0.93 and 65.4 ± 1.19) in 1996 and 1997 respectively. Reindeer grazing of old meadow in spring maintains the vegetation at a younger phenological stage during the growing season when compared with ungrazed meadow. Therefore grazing increased the quality of the herbage, but decreased herbage harvest under conditions of high grazing intensity. © 2000 Society of Chemical Industry 相似文献
28.
Brekke S Ingul CB Aase SA Torp HG 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2006,53(5):936-946
The diagnostic value of echocardiographic images seems to diminish when the frame rate is low. In this work, morphing based on velocity information was used to improve the perceived smoothness of B-mode cine-loops with low frame rate. Based on an estimate of the velocity field calculated from B-mode speckle tracking and tissue Doppler measurements, morphed cine-loops with arbitrarily high frame rate were created. Morphing was applied to cardiac ultrasound cine-loops with apical insonation. The quality of the morphed data was evaluated by removing frames from duplex B-mode and tissue Doppler recordings, then replacing the removed B-mode frames with morphed ones. The decimated and morphed sequences were compared to the original ones. Wall motion scoring, a subjective evaluation technique for regional viability of the myocardium, was applied to data from 20 patients with varying pathology. Sixty cine-loops were scored twice, first with original data and later with morphed data. The results were compared for each recording, and the scorings were identical in the two cases for 94% of the segments. We conclude that much of the diagnostic value is retained in recordings with 15 frames per second when temporal morphing is applied. 相似文献
29.
S. Suwarno J.K. Solberg J.P. Maehlen B. Krogh V.A. Yartys 《International Journal of Hydrogen Energy》2012
In the present work, we studied the effects of Cr on the crystal structures and hydrogen storage properties of ternary alloys, Ti0.7V0.3−xCrx and Ti0.8V0.2−xCrx. Metal–hydrogen interactions were characterised by Thermal Desorption Spectroscopy (TDS) and in situ Synchrotron X-ray diffraction (SR-XRD). All initial alloys crystallise with body-centred cubic (BCC) crystal structures formed as solid solutions of V and Cr in Ti. Upon hydrogenation, the dihydrides (Ti,V,Cr)H2 with face-centred cubic (FCC) structures are formed. An increase in the Cr content leads to systematic changes in the structure and hydrogenation behaviours. The changes include (a) contraction of the unit cells for the initial alloys and for the corresponding dihydrides; (b) slower hydrogen absorption kinetics and an increase in the incubation period for hydrogenation; (c) a decrease in the thermal stability of the saturated hydrides; and (d) a reduction in the apparent activation energy of hydrogen desorption. In situ SR-XRD and TDS studies of the FCC Ti–V–Cr hydrides indicated that their decomposition consists of five individual desorption events. 相似文献
30.
Navaneethan Muthuswamy Jose Luis Gomez de la Fuente Dung T. Tran John Walmsley Mikhail Tsypkin Steinar Raaen Svein Sunde Magnus Rønning De Chen 《International Journal of Hydrogen Energy》2013
The present work presents a method to encapsulate pre-synthesised Ru nanoparticles (NPs) by Pt using a polyol method without capping agents at various pH values (6, 7, 8 and 10). The structural and surface properties of the catalysts were characterised using X-ray diffraction, transmission electron microscopy, CO stripping, and energy-dispersive X-ray spectroscopy. The studies suggest that the pH during encapsulation of Ru by Pt plays an important role in controlling of shell composition. A core–shell catalyst with an alloy shell was obtained at a pH of 6, whereas a monometallic Pt shell was obtained at a pH of 10. The core–shell catalysts gave higher steady-state current for methanol oxidation: 10-fold higher for alloy shells and 5-fold higher for Pt-enriched shells compared to the pure Pt catalyst. It is suggested that the highest catalytic enhancement of the core–shell catalysts is obtained through the bi-functional character that dominates the alloy shells rather than the ligand-effect-promoted Pt-enriched shells. 相似文献