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排序方式: 共有744条查询结果,搜索用时 12 毫秒
51.
Jens Bender Dennis Kügler Marian Margraf Ingo Naumann 《Datenschutz und Datensicherheit - DuD》2010,34(5):295-298
Dieser Artikel beschreibt im Detail die datenschutzfreundliche Ausgestaltung des Sperrmanagements, wie es im neuen deutschen Personalausweis zum Einsatz kommt. 相似文献
52.
Turek Marian 《中国矿业大学学报(英文版)》2011,21(1)
The author presents the results being the effect of the analysis of innovative rate of individual technologies applied in opening up, development and extraction works which was carried out within the project: "scenarios of technological development of hard coal extractive industry". After presentation of opening up, development and extraction technologies that are applied in Polish hard coal industry and their classification with regard to innovation degree the author describes those technologies in a detailed manner. He brings attention to the most effective systems for hard coal deposits' opening up, development and their extraction, including the extraction of the residual coal. The attention is also paid to the safety level of the applied technologies. 相似文献
53.
Peter Kubatka Martin Kello Karol Kajo Marek Samec Alena Liskova Karin Jasek Lenka Koklesova Tomas Kuruc Marian Adamkov Karel Smejkal Emil Svajdlenka Peter Solar Martin Pec Dietrich Büsselberg Vladimira Sadlonova Jan Mojzis 《International journal of molecular sciences》2021,22(1)
Comprehensive scientific data provide evidence that isolated phytochemicals or whole plant foods may beneficially modify carcinogenesis. The aim of this study was to evaluate the oncostatic activities of Rhus coriaria L. (sumac) using animal models (rat and mouse), and cell lines of breast carcinoma. R. coriaria (as a powder) was administered through the diet at two concentrations (low dose: 0.1% (w/w) and high dose: 1 % (w/w)) for the duration of the experiment in a syngeneic 4T1 mouse and chemically-induced rat mammary carcinoma models. After autopsy, histopathological and molecular analyses of tumor samples in rodents were performed. Moreover, in vitro analyses using MCF-7 and MDA-MB-231 cells were conducted. The dominant metabolites present in tested R. coriaria methanolic extract were glycosides of gallic acid (possible gallotannins). In the mouse model, R. coriaria at a higher dose (1%) significantly decreased tumor volume by 27% when compared to controls. In addition, treated tumors showed significant dose-dependent decrease in mitotic activity index by 36.5% and 51% in comparison with the control group. In the chemoprevention study using rats, R. coriaria at a higher dose significantly reduced the tumor incidence by 20% and in lower dose non-significantly reduced tumor frequency by 29% when compared to controls. Evaluations of the mechanism of oncostatic action using valid clinical markers demonstrated several positive alterations in rat tumor cells after the treatment with R. coriaria. In this regard, histopathological analysis of treated tumor specimens showed robust dose-dependent decrease in the ratio of high-/low-grade carcinomas by 66% and 73% compared to controls. In treated rat carcinomas, we found significant caspase-3, Bax, and Bax/Bcl-2 expression increases; on the other side, a significant down-regulation of Bcl-2, Ki67, CD24, ALDH1, and EpCam expressions and MDA levels. When compared to control specimens, evaluation of epigenetic alterations in rat tumor cells in vivo showed significant dose-dependent decrease in lysine methylation status of H3K4m3 and H3K9m3 and dose-dependent increase in lysine acetylation in H4K16ac levels (H4K20m3 was not changed) in treated groups. However, only in lower dose of sumac were significant decreases in the expression of oncogenic miR210 and increase of tumor-suppressive miR145 (miR21, miR22, and miR155 were not changed) observed. Finally, only in lower sumac dose, significant decreases in methylation status of three out of five gene promoters–ATM, PTEN, and TIMP3 (PITX2 and RASSF1 promoters were not changed). In vitro evaluations using methanolic extract of R. coriaria showed significant anticancer efficacy in MCF-7 and MDA-MB-231 cells (using Resazurin, cell cycle, annexin V/PI, caspase-3/7, Bcl-2, PARP, and mitochondrial membrane potential analyses). In conclusion, sumac demonstrated significant oncostatic activities in rodent models of breast carcinoma that were validated by mechanistic studies in vivo and in vitro. 相似文献
54.
Hakan Cevikalp Marian Neamtu Atalay Barkana 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2007,37(4):937-951
The common vector (CV) method is a linear subspace classifier method which allows one to discriminate between classes of data sets, such as those arising in image and word recognition. This method utilizes subspaces that represent classes during classification. Each subspace is modeled such that common features of all samples in the corresponding class are extracted. To accomplish this goal, the method eliminates features that are in the direction of the eigenvectors corresponding to the nonzero eigenvalues of the covariance matrix of each class. In this paper, we introduce a variation of the CV method, which will be referred to as the modified CV (MCV) method. Then, a novel approach is proposed to apply the MCV method in a nonlinearly mapped higher dimensional feature space. In this approach, all samples are mapped into a higher dimensional feature space using a kernel mapping function, and then, the MCV method is applied in the mapped space. Under certain conditions, each class gives rise to a unique CV, and the method guarantees a 100% recognition rate with respect to the training set data. Moreover, experiments with several test cases also show that the generalization performance of the proposed kernel method is comparable to the generalization performances of other linear subspace classifier methods as well as the kernel-based nonlinear subspace method. While both the MCV method and its kernel counterpart did not outperform the support vector machine (SVM) classifier in most of the reported experiments, the application of our proposed methods is simpler than that of the multiclass SVM classifier. In addition, it is not necessary to adjust any parameters in our approach. 相似文献
55.
This paper presents the existing techniques for P system testing and performs an empirical evaluation of their fault-detection efficiency. The comparison is performed using mutation testing and, based on the results obtained, some improved testing methodologies are proposed. 相似文献
56.
A genetic algorithm for the optimisation of assembly sequences 总被引:6,自引:0,他引:6
This paper describes a Genetic Algorithm (GA) designed to optimise the Assembly Sequence Planning Problem (ASPP), an extremely diverse, large scale and highly constrained combinatorial problem. The modelling of the ASPP problem, which has to be able to encode any industrial-size product with realistic constraints, and the GA have been designed to accommodate any type of assembly plan and component. A number of specific modelling issues necessary for understanding the manner in which the algorithm works and how it relates to real-life problems, are succinctly presented, as they have to be taken into account/adapted/solved prior to Solving and Optimising (S/O) the problem. The GA has a classical structure but modified genetic operators, to avoid the combinatorial explosion. It works only with feasible assembly sequences and has the ability to search the entire solution space of full-scale, unabridged problems of industrial size. A case study illustrates the application of the proposed GA for a 25-components product. 相似文献
57.
Kate Sanders Sally Fincher Dennis Bouvier Gary Lewandowski Briana Morrison Laurie Murphy Marian Petre Brad Richards Josh Tenenberg Lynda Thomas Richard Anderson Ruth Anderson Sue Fitzgerald Alicia Gutschow Susan Haller Raymond Lister Renée McCauley John McTaggart Christine Prasad Terry Scott Dermot Shinners-Kennedy Suzanne Westbrook Carol Zander 《Expert Systems》2005,22(3):121-128
Abstract: This paper presents a case study of the use of a repeated single‐criterion card sort with an unusually large, diverse participant group. The study, whose goal was to elicit novice programmers' knowledge of programming concepts, involved over 20 researchers from four continents and 276 participants drawn from 20 different institutions. In this paper we present the design of the study and the unexpected result that there were few discernible systematic differences in the population. The study was one of the activities of the National Science Foundation funded Bootstrapping Research in Computer Science Education project (2003). 相似文献
58.
Keri K. Stephens Renee L. Cowan Marian L. Houser 《Journal of Computer-Mediated Communication》2011,16(2):228-249
Relying on SIDE theory, this 2 × 2 experimental design tested the effects of adherence to organizational norms and interpersonal familiarity in e‐mail messages from both superior and subordinate perspectives. Results reveal that using norm‐congruent e‐mail messages account for over 50% of the variance in both superior and subordinate attitudes toward the message and between 30% and 56% of the variance in perceptions of source credibility. Data from the superiors indicate that norm congruent e‐mail messages account for 14.4% of the variance in message compliance. Results from subordinates reveal an interaction effect that is consistent with SIDE‐based predictions. Subordinates believe superiors are most likely to comply with e‐mail requests from unfamiliar subordinates that are crafted in a manner congruent with organizational norms. 相似文献
59.
Marian Walter Benjamin Eilebrecht Tobias Wartzek Steffen Leonhardt 《Personal and Ubiquitous Computing》2011,15(7):707-715
Embedded wireless sensors are important components of mobile distributed computing networks, and one of the target applications
areas is health care. The preservation of mobility for senior citizens is one of the key issues in maintaining an independent
lifestyle. Thus health technologies inside a car can contribute both to safety issues (supervision of driver fitness) as well
as healthcare issues by monitoring vitals signs imperceptibly. In this paper, three embedded measurement techniques for non-contact
monitoring of vital signals have been investigated. Specifically, capacitive electrocardiogram (cECG) monitoring, mechanical
movement analysis (ballistocardiogram, BCG) using piezo-foils and inductive impedance monitoring were examined regarding their
potential for integration into car seats. All three sensing techniques omit the need for electroconductive contact to the
human body, but require defined mechanical boundary conditions (stable distances or, in the case of BCG, frictional connection).
The physical principles of operation, the specific boundary conditions regarding automotive integration and the results during
wireless operation in a running car are presented. All three sensors were equipped with local intelligence by incorporating
a microcontroller. To eliminate the need for additional cabling, a wireless Bluetooth communication module was added and used
to transmit data to a measurement PC. Finally, preliminary results obtained during test drives on German city roads and highways
are discussed. 相似文献
60.
Marian Counihan 《Journal of Logic, Language and Information》2008,17(4):391-415
In this paper we explore differences in use of the so-called ‘logical’ elements of language such as quantifiers and conditionals,
and use this to explain differences in performance in reasoning tasks across subject groups with different educational backgrounds.
It is argued that quantified sentences are difficult natural bases for reasoning, and hence more prone to elicit variation
in reasoning behaviour, because they are chiefly used with a pre-determined domain in everyday speech. By contrast, it is
argued that conditional sentences form natural premises because of the function they serve in everyday speech. Implications
of this for the role of logic in modelling human reasoning behaviour are briefly considered. 相似文献