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91.
Ryszard Smarzewski 《Proceedings of the American Mathematical Society》1997,125(5):1391-1397
We give a new characterization of the set of all extreme points of the unit ball in the Banach space of all Lipschitz functions on a metric space This result is applied to get a total variation characterization of in the particular case when is a convex subset of a Banach space.
92.
93.
Bierla K Dernovics M Vacchina V Szpunar J Bertin G Lobinski R 《Analytical and bioanalytical chemistry》2008,390(7):1789-1798
A method was developed for the simultaneous determination of selenomethionine (SeMet) and selenocysteine (SeCys) in meat (chicken
and lamb muscles) and different offal tissues (heart, liver, kidney). The analytical procedure was based on the protein extraction
with urea under reducing conditions (dithiothreitol), derivatization of SeCys and SeMet by carbamidomethylation with iodoacetamide
(IAM) followed by quantitative proteolysis. The mixture of the derivatized Se-amino acids was purified by size-exclusion liquid
chromatography (LC) and analysed by ion-paring reversed-phase HPLC–inductively coupled plasma mass spectroscopy (ICP MS).
The quantification of SeCys and SeMet was carried out by the method of standard additions. 77SeMet was used to control the SeMet derivatization efficiency and recovery. The method was validated by the determination
of the Se mass balance. The Se-amino acids accounted for 91 ± 8% of the total selenium (mean of 95 samples of seven tissues
analysed over a period of 18 months). The method was applied to the discrimination of the contribution of selenoproteins (containing
SeCys) and other Se-containing proteins (containing SeMet) in tissues of animals during supplementation studies (dose–effect
and tolerance). 相似文献
94.
Mahide Küçük Ryszard Urbański Jerzy Grzybowski Yalçın Küçük İlknur Atasever Güvenç 《Optimization》2016,65(11):1949-1961
In this study, some relationships between quasidifferentiability and weakly subdifferentiability of a function are investigated, and some results on calculating the quasidifferential in terms of weak exhausters are presented. Moreover, under some assumptions weak subdifferentiability of a quasidifferentiable function is proved and the weak subdifferential is obtained by using the quasidifferential. Under some assumptions, it is proved that a positively homogeneous and lower semicontinuous function is quasidifferentiable. It is also shown that directional differentiability and weak subdifferentiability imply quasidifferentiability. Furthermore, a method to evaluate the quasidifferential is given by using reduced weak lower exhausters. 相似文献
95.
A three-step chromatographic procedure using orthogonal separation mechanisms (size-exclusion, cation-exchange and ion-pairing reversed phase) was developed to purify three low molecular weight selenospecies, including the major compound, from the aqueous extract of monkeypot (Lecythis minor) nuts. The following reversed-phase nanoHPLC-electrospray Q-TOF-MS/MS allowed the formal standardless identification of selenocystathionine and two isoforms of gamma-glutamyl-selenocystathionine. This is the first MS and MS/MS-based formal evidence of the presence of these compounds in a biological sample. 相似文献
96.
Glutathione peroxidase (isolated from bovine erythrocytes) and its behaviour during alkylation and enzymatic digestion were
studied by various hyphenated techniques: gel electrophoresis–laser ablation (LA) inductively coupled plasma (ICP) mass spectrometry
(MS), size-exclusion liquid chromatography–ICP MS, capillary high-performance liquid chromatography (capHPLC)–ICP MS, matrix-assisted
laser desorption/ionization (MALDI) time-of-flight (TOF) MS, electrospray MS, and nanoHPLC–electrospray ionization (ESI) MS/MS.
ESI TOF MS and MALDI TOF MS allowed the determination of the molecular mass but could not confirm the presence of selenium
in the protein. The purity of the protein with respect to selenium species could be evaluated by LA ICP MS and size-exclusion
chromatography (SEC)–ICP MS under denaturating and nondenaturating conditions, respectively. SEC–ICP MS and capHPLC–ICP MS
turned out to be valuable techniques to study the enzymolysis efficiency, miscleavage and artefact formation during derivatization
and tryptic digestion. For the first time the parallel ICP MS and ESI MS/MS data are reported for the selenocysteine-containing
peptide extracted from the gel; capHPLC–ICP MS allowed the sensitive detection of the selenopeptide regardless of the matrix
and nanoHPLC–electrospray made possible its identification.
Figure Eye catching image
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
97.
98.
Domenico Catalano Filip Defever Ryszard Deszcz Marian Hotloś Zbigniew Olszak 《Abhandlungen aus dem Mathematischen Seminar der Universit?t Hamburg》1999,69(1):59-65
For anyn ≥ 2, we give examples of almost Kähler conformally flat manifoldsM 2n which are not Kähler. We discuss the meaning of these examples in the context of the Goldberg conjecture on almost Kahler manifolds. 相似文献
99.
Photovoltaic phenomenon in tetracene and pentacene layers evaporated under the same conditions onto a glass substrate and provided with the same couple of electrodes is investigated. Comparison of the results obtained for both organic materials makes it possible to conclude that in spite of differences in mechanisms of charge carrier generation, the values of photovoltaic parameters are very similar. 相似文献
100.
Artificial neural networks have become the go-to solution for computer vision tasks, including problems of the security domain. One such example comes in the form of reidentification, where deep learning can be part of the surveillance pipeline. The use case necessitates considering an adversarial setting—and neural networks have been shown to be vulnerable to a range of attacks. In this paper, the preprocessing defences against adversarial attacks are evaluated, including block-matching convolutional neural network for image denoising used as an adversarial defence. The benefit of using preprocessing defences comes from the fact that it does not require the effort of retraining the classifier, which, in computer vision problems, is a computationally heavy task. The defences are tested in a real-life-like scenario of using a pre-trained, widely available neural network architecture adapted to a specific task with the use of transfer learning. Multiple preprocessing pipelines are tested and the results are promising. 相似文献