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131.
The qualitative action-project method is described as an appropriate and heuristic qualitative research method for use in counseling psychology. Action theory, which addresses human intentional, goal-directed action, project, and career, provides the conceptual framework for the method. Data gathering and analysis involve multiple procedures to access information from 3 perspectives: manifest behavior, internal processes, and social meaning. The method has a number of advantages, including its conceptualization, which is close to human experience; its systematic data gathering and analysis procedures; its usefulness in describing processes of interest to counseling psychologists; and its uniqueness among qualitative research methods. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
132.
The interaction of semiconducting single wall carbon nanotubes (SWCNT) and the conducting polymer poly(3,4-ethylendioxythiophene/polystyrenesulfonate) (PEDOT/PSS) was studied by Raman spectroscopy and in-situ Raman spectroelectrochemistry. The mixing of SWCNT with PEDOT/PSS caused a partial doping of SWCNT as indicated by the change of the relative intensity of the Raman features of SWCNT. The in situ Raman spectroelectrochemical measurements showed that semiconducting tubes could be doped even if they are embedded in PEDOT/PSS. However, in contrast to the neat SWCNT, the doping of SWCNT in composite is less efficient. For SWCNT in composite it is necessary to apply larger potential (by about 0.4–0.6 V) to achieve the same level of bleaching of Raman bands as in the case of neat SWCNT. 相似文献
133.
Anna Vasatkova Sarka Krizova Vojtech Adam Ladislav Zeman Rene Kizek 《International journal of molecular sciences》2009,10(3):1138-1160
Mycotoxins are secondary metabolites produced by microfungi that are capable of causing disease and death in humans and other animals. This work was aimed at investigation of influence of mouldy wheat contaminated by pathogenic fungi producing mycotoxins on metallothionein levels in hepatic tissue of rats. The rats were administrating feed mixtures with different contents of vitamins or naturally mouldy wheat for 28 days. It was found that the wheat contained deoxynivalenol (80 ± 5 μg per kg of mouldy wheat), zearalenone (56 ± 3 μg/kg), T2-toxin (20 ± 2 μg/kg) and aflatoxins as a sum of B1, B2, G1 and G2 (3.9 ± 0.2 μg/kg). Rats were fed diets containing 0, 33, 66 and 100% naturally moulded wheat. Control group 0, 33, 66 and 100% contained vitamins according to Nutrient Requirements of Rats (NRC). Other four groups (control group with vitamins, vit33, vit66 and vit100%) were fed on the same levels of mouldy wheat, also vitamins at levels 100% higher than the previous mixtures. We determined weight, feed conversion and performed dissection to observe pathological processes. Changes between control group and experimental groups exposed to influence of mouldy wheat and experimental groups supplemented by higher concentration of vitamins and mouldy wheat were not observed. Livers were sampled and did not demonstrate significant changes in morphology compared to control either. In the following experiments the levels of metallothionein as a marker of oxidative stress was determined. We observed a quite surprising trend in metallothionein levels in animals supplemented with increased concentration of vitamins. Its level enhanced with increasing content of mouldy wheat. It was possible to determine a statistically significant decline (p<0.05) between control group and groups of animals fed with 33, 66 and 100% mouldy wheat. It is likely that some mycotoxins presented in mouldy wheat are able to block the mechanism of metallothionein synthesis. 相似文献
134.
Rushita Shah Zuzana Kronekova Anna Zahoranová Ladislav Roller Nabanita Saha Petr Saha Juraj Kronek 《Journal of materials science. Materials in medicine》2015,26(4):157
Polymers based on 2-oxazoline, such as poly(2-ethyl-2-oxazolines) (PETOx), are considered to be a type of ‘pseudopeptide’ with the ability to form novel biomaterials. The hydrolysis of PETOx was carried out to evaluate its use in biomedical applications. In the present work, PETOx samples with a range of molar masses were prepared by living cationic polymerization. Hydrolysis was carried out at time intervals ranging from 15 to 180 min to prepare copolymers with different amounts of ethylene imine units. 1H NMR spectroscopy was used to identify the structure of the hydrolyzed polymers. The dependence of in vitro cell viability on the degree of hydrolysis was determined using three different model cell lines, namely, mouse embryonic 3T3 fibroblasts, pancreatic βTC3 cells, and mouse lymphoid macrophages P388.D1. It was demonstrated that increasing the degree of hydrolysis decreased cell viability for all cell types. Fibroblast cells displayed the highest tolerance; additionally, the effect of polymer size showed no observable significance. Macrophage cells, immune system representatives, displayed the highest sensitivity to contact with hydrolyzed PETOx. The effect of polymer hydrolysis, polymer concentration and the incubation time on cell viability was experimentally observed. Confocal laser-scanning microscopy provided evidence of cellular uptake of pyrene-labeled (co)polymers. 相似文献
135.
136.
Pavel Klener Dana Sovilj Nicol Renesova Ladislav Andera 《International journal of molecular sciences》2021,22(18)
Hematologic malignancies (HM) comprise diverse cancers of lymphoid and myeloid origin, including lymphomas (approx. 40%), chronic lymphocytic leukemia (CLL, approx. 15%), multiple myeloma (MM, approx. 15%), acute myeloid leukemia (AML, approx. 10%), and many other diseases. Despite considerable improvement in treatment options and survival parameters in the new millennium, many patients with HM still develop chemotherapy-refractory diseases and require re-treatment. Because frontline therapies for the majority of HM (except for CLL) are still largely based on classical cytostatics, the relapses are often associated with defects in DNA damage response (DDR) pathways and anti-apoptotic blocks exemplified, respectively, by mutations or deletion of the TP53 tumor suppressor, and overexpression of anti-apoptotic proteins of the B-cell lymphoma 2 (BCL2) family. BCL2 homology 3 (BH3) mimetics represent a novel class of pro-apoptotic anti-cancer agents with a unique mode of action—direct targeting of mitochondria independently of TP53 gene aberrations. Consequently, BH3 mimetics can effectively eliminate even non-dividing malignant cells with adverse molecular cytogenetic alterations. Venetoclax, the nanomolar inhibitor of BCL2 anti-apoptotic protein has been approved for the therapy of CLL and AML. Numerous venetoclax-based combinatorial treatment regimens, next-generation BCL2 inhibitors, and myeloid cell leukemia 1 (MCL1) protein inhibitors, which are another class of BH3 mimetics with promising preclinical results, are currently being tested in several clinical trials in patients with diverse HM. These pivotal trials will soon answer critical questions and concerns about these innovative agents regarding not only their anti-tumor efficacy but also potential side effects, recommended dosages, and the optimal length of therapy as well as identification of reliable biomarkers of sensitivity or resistance. Effective harnessing of the full therapeutic potential of BH3 mimetics is a critical mission as it may directly translate into better management of the aggressive forms of HM and could lead to significantly improved survival parameters and quality of life in patients with urgent medical needs. 相似文献
137.
The D band in the Raman spectra of single walled carbon nanotubes is considered as an indicator of defects in carbon nanotubes. However, its dependence on charge-transfer doping is generally ignored, despite the studied samples are often naturally doped. We studied the intensity of the D band, the ratio of the intensities of the D band and TG band (ID/ITG) and the ratio of the intensities of the D and G′ band (ID/IG′) in the Raman spectra of the single walled carbon nanotubes in dependence on a doping level. We tested two laser excitation energies viz 2.41 and 1.92 eV, which are in resonance with semiconducting and metallic tubes, respectively in our sample. It is shown that the D band intensity is significantly attenuated in doped carbon nanotubes sample for both semiconducting and metallic tubes. The ID/ITG ratio is weakly dependent on doping for semiconducting tubes but for metallic tubes the ID/ITG ratio exhibits strong dependence on doping. The ID/IG′ ratio is suggested for evaluation of the defects in carbon nanotubes samples since it is less sensitive to doping both for semiconducting and metallic tubes. Nevertheless, for highly doped samples even the ID/IG′ ratio exhibits significant dependence on doping level. 相似文献
138.
Cluster points of sequences of fuzzy real numbers 总被引:1,自引:1,他引:0
Jaroslav Hančl Ladislav Mišík János T. Tóth 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2010,14(4):399-404
Properties of cluster points of sequences of fuzzy real numbers are investigated in the paper. It is shown that some similar theorems like in the case of real sequences hold. On the other hand, some differences from real case are discussed. 相似文献
139.
The correlated band theory methods, the around-mean-field LDA + U and dynamical LDA + HIA (Hubbard-I), are applied to investigate the electronic structure of Pu chalcogenides. The LDA + U calculations for PuX (X = S, Se, Te) provide non-magnetic ground state in agreement with the experimental data. Non-integer filling of 5f-manifold (from approx. 5.6 in PuS to 5.7 PuTe). indicates a mixed valence ground state which combines f5 and f6 multiplets. Making use of the dynamical LDA+HIA method the photoelectron spectra are calculated in good agreement with experimental data. The three-peak feature near EF attributed to 5f-manifold is well reproduced by LDA + HIA, and follows from mixed valence character of the ground state. 相似文献
140.
Utilization of two-directional AC current distribution for enhancing sizing ability of electromagnetic nondestructive testing methods 总被引:2,自引:2,他引:0
This paper proposes a novel method for accurately evaluating the depth of a defect using electromagnetic phenomena. The novel method induces AC currents inside a conductive medium and detects the disturbance of the currents. Whereas the principle itself has been utilized in conventional methods, the uniqueness of this new method lies in realizing a current distribution in which there is a region where currents near the surface and those deeply inside the specimen flow opposite to each other. The novel method provides a clear indication corresponding to the depth of the inspected defect. In addition, it enables one to evaluate the depth of a defect that is much deeper than the depth of penetration. After the physical background of this new method is explained, the results of experimental verifications and subsequent numerical simulations are presented. 相似文献