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排序方式: 共有805条查询结果,搜索用时 0 毫秒
41.
Zusammenfassung OpenSocial definiert eine Menge von Programmierschnittstellen für Anwendungen von Drittanbietern im Kontext sozialer Netzwerke.
Unter der Verwendung von Standardtechnologien wie HTML und JavaScript k?nnen Entwickler interoperable Anwendungen erstellen,
die auf den sozialen Graphen des jeweiligen Netzwerks zugreifen. 相似文献
42.
43.
Karsten Schmidt 《International Journal on Software Tools for Technology Transfer (STTT)》2006,8(3):195-203
In the context of Petri nets, we propose an automated construction of a progress measure which is an important pre-requisite for a state space reduction technique called the sweep-line method. Our construction is based on linear-algebraic techniques concerning the transition vectors of the Petri net under consideration.
We further discuss the possible combination of the sweep-line method with other state space reduction techniques (partial
order reduction, the symmetry method). 相似文献
44.
Molecular-dynamics simulations on ion-beam deposition of boron nitride are presented. A realistic Tersoff-like potential energy functional for boron nitride, which was specially fitted to ab initio-data, has been used. The impact of energetic boron and nitrogen atoms on a c-BN target is simulated with energies ranging from 10 to 600 eV. The structural analysis of the grown films shows that a loose, dominantly sp2-bonded structure arises at high ion flux. In no case the formation of a sp3-bonded phase is observed, but the obtained films partially reveal textured basal planes as found in experiment. Two different growth regimes are identified for ion energies above and below 100 eV. 相似文献
45.
After hyperimmunization of laying hens with Salmonella enteritidis, antibodies can be found in egg yolks. This study was conducted to ascertain whether the growth of S. enteritidis would be suppressed in the presence of antibodies contained in egg yolk. Specifically pathogen-free (SPF)-laying hens were immunized with S. enteritidis; eggs were collected, the yolk was separated and the concentration of S. enteritidis antibodies was determined quantitatively by using the enzyme-linked immunosorbent assay (ELISA), the radial immunodiffusion and the bicinchoninic acid protein assay. Then, the yolk was inoculated with approximately 10, 100 or 1000 S. enteritidis cells/ml and incubated at 15, 20 and 30 degrees C for 0, 2, 6 and 24 h. The growth of organisms in each yolk was examined, and the generation times were calculated. The egg yolk from nonimmunized hens served as negative control. The highest level of antibody concentration was found in the hyperimmunized group. There was no difference in the generation times of S. enteritidis between the antibody-positive yolk and the negative yolk at the three different incubation temperatures. The results suggest that antibodies in the yolk do not influence the growth of S. enteritidis, even if the hens are highly immunized. 相似文献
46.
This study quantifies the surface chemical heterogeneity of bacteriogenic iron oxides (BIOS) and its end-members (2-line ferrihydrite and intermixed intact and fragmented bacteria). On a dry weight basis, BIOS consisted of 64.5 +/- 1.8% ferrihydrite and 34.5 +/- 1.8% organic matter. Enrichment of Al, Cu, Cr, Mn, Sr, and Zn was shown in the solid versus the aqueous phase (1.9 < log Kd < 4.2). Within the solid-phase Al (69.5%), Cu (78.7%), and Zn (77.9%) were associated with the bacteria, whereas Cr (59.8%), Mn (99.8%), and Sr (79.4%) preferred ferrihydrite. Acid-base titration data from the BIOS and bacteria were fitted using FOCUS pKa spectroscopy. The bacteria spectrum with pKa's of 4.18 +/- 0.37, 4.80 +/- 0.54, 6.98 +/- 0.45, and 9.75 +/- 0.68 was similar to discrete and continuous spectra for intact and fragmented bacteria. The BIOS spectrum recorded pKa's of 4.27 +/- 0.51, 6.61 +/- 0.51, 7.89 +/- 1.10, and 9.65 +/- 0.66 and was deconvoluted to remove overlapping binding site contributions from the bacteria. The resulting residual iron oxide spectrum coincided with discrete MUSIC spectra for goethite and lepidocrocite with pKa values of 4.10 +/- 0.43, 6.53 +/- 0.45, 7.81 +/- 0.76, and 9.51 +/- 0.68. Surface site density analysis showed that acidic sites (pKa < 6) were contributed by the bacteria (37%), whereas neutral sites (6 < pKa < 8) were characteristic of the iron oxide fraction (35%). Basic sites (8 < pKa) were higher in the bacteria (57%), than in the BIOS (44%) or iron oxide fractions (47%). This analysis suggested a high degree of bacterial group masking and a similarity between the BIOS and goethite surface reactivity. An understanding of the BIOS surface chemical heterogeneity and inherent proton and metal binding capacity was obtained through the use of FOCUS apparent pKa spectroscopy. 相似文献
47.
Antiproliferative properties of molecular regulators of lipid metabolism have been increasingly studied during recent years.
Discussion is ongoing concerning optimal treatment conditions and assays used for monitoring proliferation and cytotoxicity.
The objective of the present work was to optimize methods and treatment conditions used for studying antiproliferative effects
of fatty acids and analogs, represented by palmitic acid (PA) and the β-oxidation-restricted fatty acid analog tetradecylthioacetic
acid (TTA), in rat (BT4Cn) and human (D54Mg and GaMg) glioma cell lines. Changes in [3H]thymidine incorporation preceded changes in cell number in TTA-treated glioma cell cultures, and the growth inhibition was
more significantly expressed by [3H]thymidine incorporation than cell number. Addition of bovine serum albumin decreased cellular fatty acid uptake and reduced
the effects of TTA and PA on [3H]thymidine incorporation. Determination of the antiproliferative effect of TTA in BT4Cn cells by MTT conversion and [3H]thymidine incorporation yielded concordant results. TTA-mediated reduction in cell number corresponded to reduction in cellular
protein and total DNA content in BT4Cn cells. Reduced growth potential in TTA-treated multicellular D54Mg and GaMg spheroids
supported the findings from monolayer cultures. In conclusion, cell density, treatment period, fatty acid administration,
and methods for growth determination may profoundly influence the outcome of cell growth experiments. Thus, experimental conditions
should be carefully controlled when performing cell growth experiments, and effects on cell growth should preferably be confirmed
by different methods.
Karl Johan Tronstad and Kjetil Berge contributed equally to this article. 相似文献
48.
Future trends in data mining 总被引:3,自引:1,他引:3
Hans-Peter Kriegel Karsten M. Borgwardt Peer Kröger Alexey Pryakhin Matthias Schubert Arthur Zimek 《Data mining and knowledge discovery》2007,15(1):87-97
Over recent years data mining has been establishing itself as one of the major disciplines in computer science with growing
industrial impact. Undoubtedly, research in data mining will continue and even increase over coming decades. In this article,
we sketch our vision of the future of data mining. Starting from the classic definition of “data mining”, we elaborate on
topics that — in our opinion — will set trends in data mining. 相似文献
49.
50.
Saso Dzeroski Steffen Schulze-Kremer Karsten R. Heidtke Karsten Siems Dietrich Wettschereck Hendrik Blockeel 《Applied Artificial Intelligence》2013,27(5):363-383
We present a novel application ofInductive Logic Programming (ILP) to the problem of diterpene structure elucidation from 13 CNMR spectra. Diterpenes are organic compounds oflow molecular weight with a skeleton of 20 carbon atoms. They are of significant chemical and commercial interest because oftheir use as lead compounds in the search for new pharmaceutical effectors. The interpretation of diterpene 13 CNMR spectra normally requires specialists with detailed spectroscopic knowledge and substantial experience in natural products chemistry, specifically knowledge on peak patterns and chemical structures. Given a database ofpeak patterns for diterpenes with known structure, we apply several ILP approaches to discover correlations between peak patterns and chemical structure. The approaches used include first - order inductive learning, relational instance based learning, induction oflogical decision trees, and inductive constraint logic. Performance close to that of domain experts is achieved, which suffices for practical use. 相似文献