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591.
Ondrej Gedeon Karel Jurek Ivo Drbohlav Nadge Ollier 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(20):3461-3465
Binary potassium-silicate glass of composition 15 mol% K2O + 85 mol% SiO2 was irradiated with 2.5 MeV. The thickness of glass was chosen so as electrons stopped near the back surface. After the high-energy irradiation both, back and top surfaces, were depleted from potassium; the back surface was depleted more than the top one. The decay curves were recorded on pristine glass, and on top and back surfaces of the glass pre-irradiated with high-energy electrons. The incubation times of the top surface increased while the incubation time of the back one decreased in comparison with the pristine glass. Observation of the volume changes induced by the following impaction of 50 keV revealed the top surface is closer to the pristine glass than the back one. 相似文献
592.
593.
Klema J. Novakova L. Karel F. Stepankova O. Zelezny F. 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2008,38(1):3-15
Sequential data represent an important source of potentially new medical knowledge. However, this type of data is rarely provided in a format suitable for immediate application of conventional mining algorithms. This paper summarizes and compares three different sequential mining approaches based, respectively, on windowing, episode rules, and inductive logic programming. Windowing is one of the essential methods of data preprocessing. Episode rules represent general sequential mining, while inductive logic programming extracts first-order features whose structure is determined by background knowledge. The three approaches are demonstrated and evaluated in terms of a case study STULONG. It is a longitudinal preventive study of atherosclerosis where the data consist of a series of long-term observations recording the development of risk factors and associated conditions. The intention is to identify frequent sequential/temporal patterns. Possible relations between the patterns and an onset of any of the observed cardiovascular diseases are also studied. 相似文献
594.
Hoelzl C Glatt H Meinl W Sontag G Haidinger G Kundi M Simic T Chakraborty A Bichler J Ferk F Angelis K Nersesyan A Knasmüller S 《Molecular nutrition & food research》2008,52(3):330-341
To find out if the cancer protective effects of Brussels sprouts seen in epidemiological studies are due to protection against DNA-damage, an intervention trial was conducted in which the impact of vegetable consumption on DNA-stability was monitored in lymphocytes with the comet assay. After consumption of the sprouts (300 g/p/d, n = 8), a reduction of DNA-migration (97%) induced by the heterocyclic aromatic amine 2-amino-1-methyl-6-phenyl-imidazo-[4,5-b]pyridine (PhIP) was observed whereas no effect was seen with 3-amino-1-methyl-5H-pyrido[4,3-b]-indole (Trp-P-2). This effect protection may be due to inhibition of sulfotransferase 1A1, which plays a key role in the activation of PhIP. In addition, a decrease of the endogenous formation of oxidized bases was observed and DNA-damage caused by hydrogen peroxide was significantly (39%) lower after the intervention. These effects could not be explained by induction of antioxidant enzymes glutathione peroxidase and superoxide dismutase, but in vitro experiments indicate that sprouts contain compounds, which act as direct scavengers of reactive oxygen species. Serum vitamin C levels were increased by 37% after sprout consumption but no correlations were seen between prevention of DNA-damage and individual alterations of the vitamin levels. Our study shows for the first time that sprout consumption leads to inhibition of sulfotransferases in humans and to protection against PhIP and oxidative DNA-damage. 相似文献
595.
Tomáš Řezanka Lucia Gharwalová Gabriela Nováková Irena Kolouchová Ondřej Uhlík Karel Sigler 《Lipids》2019,54(2-3):177-187
Four bacterial isolates, which produced polyunsaturated fatty acids (PUFA), were isolated from water samples of radioactive springs collected from Jáchymov spa. Jáchymov (Sankt Joachimsthal) is a city in northwestern Bohemia, where Marie and Pierre Curie isolated radium in 1898 from the mineral uraninite. To date, four springs (Agricola, Behounek, C1, and Curie) have been used for spa purposes, that is for the treatment of nervous and rheumatic disorders by constantly produced radioactive gas radon (222Rn) dissolved in the water. The radioactivity reaches 24 kBq/L. Using 16S rRNA gene sequence analysis, all four isolates were identified as members of the genus Kocuria, with two isolates designated 208 and 401 affiliated with Kocuria kristinae, while isolates 101 and 301 most likely with K. rhizophila. The content of fatty acids in polar lipids was determined by gas chromatography–mass spectrometry (GC–MS) and two PUFA, that is arachidonic and eicosapentaenoic, were identified. The position of double bonds was confirmed by GC–MS of 3-pyridylcarbinol (formerly picolinyl) esters. We assume that all four isolates of Kocuria produce PUFA to increase the stability of cell membranes, which may be impaired by the reaction of the reactive oxygen species. These can arise, for example, because of α radiation during 222Rn decay. 相似文献
596.
Knight Bob G.; Karel Michele J.; Hinrichsen Gregory A.; Qualls Sara H.; Duffy Michael 《Canadian Metallurgical Quarterly》2009,64(3):205
The aging of the population will increase demand for psychological services for older adults, which challenges the profession of psychology to provide those services. In response to that challenge, professional geropsychology has been developing over the past few decades to meet current and prepare for anticipated future demand. The development of a range of training opportunities is important to enable psychologists to work effectively with older adults. This article describes the Pikes Peak model for training in professional geropsychology. The model is an aspirational, competencies-based approach to training professional geropsychologists that allows for entry points at multiple levels of professional development. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
597.
The nonionogenic pyrene-based tenside, poly(ethylene glycol) pyrenebutanoate, was prepared and applied in capillary isoelectric focusing with fluorometric detection. This dye was used here as a buffer additive in capillary isoelectric focusing for a dynamic modification of the sample of proteins and microorganisms. The values of the isoelectric points of the labeled bioanalytes were calculated with use of the fluorescent pI markers and were found comparable with pI of the native compounds. The mixed cultures of proteins and microorganisms, Escherichia coli CCM 3954, Staphylococcus epidermidis CCM 4418, Proteus vulgaris, Enterococcus faecalis CCM 4224, and Stenotrophomonas maltophilia, the strains of the yeast cells, Candida albicans CCM 8180, Candida krusei, Candida parapsilosis, Candida glabrata, Candida tropicalis, and Saccharomyces cerevisiae were reproducibly focused and separated by the suggested technique. Using UV excitation for the on-column fluorometric detection, the minimum detectable amount was down to 10 cells injected on the separation capillary. 相似文献
598.
Many traffic accidents are caused by, or at least related to, inadequate mental workload, when it is either too low (vigilance) or too high (stress). Creating variations in mental workload and accident-prone driving for research purposes is difficult in the real world. In driving simulators the measurement of driver mental workload is relatively easily conducted by means of physiological measures, although good research skills are required and it is time-consuming. The fact that modern driving simulator environments are laboratory-equivalent nowadays allows full control with respect to environmental conditions, scenarios and stimuli, and enables physiological measurement of parameters of mental workload such as heart rate and brain activity. Several examples are presented to illustrate the potential of modern high-standard driving simulator environments regarding the monitoring of drivers’ mental workload during task performance. 相似文献
599.
The lower reaches of the River Dyje were heavily modified between 1975 and 1985. The river was straightened, isolating its meanders and reducing its length by 22%. As a consequence, the river bed showed a markedly lower diversity in both hydrological and morphological characteristics. Because the River Dyje forms the state boundary between the Czech Republic and Austria, fluvial activity of the lower reaches is excluded. Along the River Dyje an active alluvium has been preserved, with approximately 1300 hectares in the Czech Republic and somewhat less in Austria. The flow regime in the lower reaches is regulated by 19 water reservoirs and a number of fishponds, with a total capacity of approximately 45% of the annual drainage. These modifications have distinctly impacted the living conditions of the indigenous ichthyofauna. Based on the results of our ichthyological investigations from 1994 to 2000, we have recommended a number of modifications that could improve the environmental conditions for fishes: (i) controlled flooding of the alluvial meadows, aimed at creating conditions for the spawning of phytophilous fish species; (ii) restoration of permanent connections between separated river meanders and the River Dyje to increase the hydrological and morphological diversity in the river bed; (iii) creation of artificial pools in the floodplain to provide more suitable habitats for fishes. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
600.
Gordon Mulligan Daniel A. Griffith Curtis C. Roseman Jarmo Eronen David F. Walker Melinda Meade James Wilson Richard Newcomb Donald E. Agthe David Griffiths Karel J. Kansky Stephen Mehay Michael Rieber Patrick O'Sullivan Frederick J. Potgieter Stuart C. Aitken Wil Gesler Thomas J. Bassett Allan Persky Donald W. Jones Carol A. Ferguson Peter E. Murphy Daniel Todd Adrian Esparza Douglas A. Henderson 《The Annals of Regional Science》1988,22(2):113-159