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51.
Micha Czaja Katarzyna Skirliska-Nosek Olga Adamczyk Kamila Sofiska Natalia Wilkosz Zenon Rajfur Marek Szymoski Ewelina Lipiec 《International journal of molecular sciences》2022,23(7)
Even several thousands of DNA lesions are induced in one cell within one day. DNA damage may lead to mutations, formation of chromosomal aberrations, or cellular death. A particularly cytotoxic type of DNA damage is single- and double-strand breaks (SSBs and DSBs, respectively). In this work, we followed DNA conformational transitions induced by the disruption of DNA backbone. Conformational changes of chromatin in living cells were induced by a bleomycin (BLM), an anticancer drug, which generates SSBs and DSBs. Raman micro-spectroscopy enabled to observe chemical changes at the level of single cell and to collect hyperspectral images of molecular structure and composition with sub-micrometer resolution. We applied multivariate data analysis methods to extract key information from registered data, particularly to probe DNA conformational changes. Applied methodology enabled to track conformational transition from B-DNA to A-DNA upon cellular response to BLM treatment. Additionally, increased expression of proteins within the cell nucleus resulting from the activation of repair processes was demonstrated. The ongoing DNA repair process under the BLM action was also confirmed with confocal laser scanning fluorescent microscopy. 相似文献
52.
A. Th. Czaja 《Starch - St?rke》1981,33(6):181-183
Influence of Manuring on Starch Production and Starch Accumulation in Buck Wheat (Fagopyrum esculentum Moench). Investigation with buck wheat have shown that there exists a competition between seed production and development of vegetative organs. Under optimum conditions for vegetative organs the buck wheat plants show humble growth and the starch-containing fruits are advanced. The plants develop greater and numerous leaves and develop greater starch grains. The starch grains may be stored in the seeds, if these are already existing, but the masses of produced starch grains are stored in the parenchyma cells of the stalks. These starch grains are lost for the annual plants with the straw. 相似文献
53.
A. Th. Czaja 《Starch - St?rke》1980,32(8):253-257
Starch Granules in Vegetation. Microscopic and Submicroscopic Morphology and Evolution According to the reaction in polarized light and by the fractionated swelling in water preparations by heating the starch granules show a clear submicroscopic reaction without evidence about the chemism of the starches. In some plant tribes the starch grains of seeds show different Basic Construction Types (BC-Types) as in the vegetative organs. Some Euphorbiaceae e. g. form rod-shaped starch granules in the nonarticulated lacticifers whilst the adjacent parenchyma cells contain round envelope starch granules. Most of the Pteridophyta, Coniferophyta, Ginkgo, Chlamydospermae and primary Monocotyledons show the so-called Pteridophyta Bas. Constr. Types, resulting from different but unknown behaviour. The multiplicity of starch granules is not only to explain by the polymer carbohydrates, length of chains, ramification and so forth but by the cooperation of “internal” substances of the starch granules from the substratum formed by the amyloplasts. In the Monocotyledons and Dicotyledons exists an increasing tendency to substitute starch granules by other storage substances. 相似文献
54.
Synthesis and catalytic properties for olefin polymerization of new vanadium complexes containing silsesquioxane ligands with different denticity
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Marzena Białek Monika Pochwała Adrian Franczyk Krystyna Czaja Bogdan Marciniec 《Polymer International》2017,66(6):960-967
A series of new vanadium‐silsesquioxanes ( 2a ? 2d ) was prepared by reacting VCl4 with not fully condensed silsesquioxanes (having from one to four silanol groups) and evaluated as pre‐catalysts in olefin polymerization. The activation of 2a ? 2d with EtAlCl2 generated highly active catalysts for ethylene polymerization, yielding high molar mass polymers with narrow dispersity. Ultra‐high molar mass polyethylenes, M w up to 4 × 106 g mol?1, were obtained with methylaluminoxane and Al(i Bu)3/[Ph3C][B(C6F5)4] as activators. Upon treatment with methylaluminoxane and boron compounds, all vanadium pre‐catalysts were active in 1‐octene polymerization as well, and produced isotactic‐rich poly(1‐octene)s with moderate monomer conversion (up to 23%). The polymerization parameters were optimized and the effect of the silsesquioxane structure on the catalytic activity and polymer properties was studied. © 2017 Society of Chemical Industry 相似文献
55.
Czaja Sara J.; Schulz Richard; Lee Chin Chin; Belle Steven H. 《Canadian Metallurgical Quarterly》2003,18(3):385
This article presents a comprehensive conceptual framework and methodology for characterizing multidimensional psychosocial and behavioral interventions for family caregivers of people with Alzheimer's disease. The methodology involved conducting a detailed task analysis of the interventions, and the application of the analytical hierarchy process. The authors were able to achieve high levels of consistency and reliability using this methodology to decompose and describe the interventions according to a complex conceptual framework comprising 3 dimensions: target domain, functional domain, and delivery system characteristics. Application of this methodology will enhance the ability to describe and measure interventions consistently, make comparisons across studies, isolate causal factors that achieve desired outcomes, and more generally elevate the science of psychosocial intervention research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
Sara J. Czaja Katka Hammond James J. Blascovich Helen Swede 《Behaviour & Information Technology》1989,8(4):309-319
The increased use of computer technology in most occupations means that many middle-aged and older workers who lack computer experience will need to acquire skills to interact with this technology. This study examined age-group differences in learning to use a text-editing system. One hundred and thirty-five females ranging in age from 25 to 70 participated in the study. They received training under one of three training conditions: instructor-based, online or manual-based. Age differences were assessed by comparing performance on criterion tasks. Results indicated significant differences among the groups in learning success, younger learners being the most successful. There were no significant age by training interactions. The findings indicate a need to develop more effective training strategies to teach older learners to use computer technologies. They also indicate the need for changes in system design because computer applications are difficult for novice users to learn. 相似文献
57.
There is little consensus regarding the extent of surgical ablation that is needed to attain cure in early-stage hypopharyngeal carcinoma (HPC). To determine effective surgical management of early-stage HPC, we retrospectively reviewed all cases of stage I or stage II HPC treated at our institution between 1970 and 1992. Of 305 patients identified with HPC, 50 (16%) had stage I (N = 13) or stage II (N = 37) cancer at diagnosis. Thirty-seven of the 50 (74%) underwent surgery alone or combined with preoperative or postoperative radiotherapy (RT). Patients were divided into three surgical groups. Group 1 underwent partial pharyngectomy (N = 9), group 2 underwent total laryngectomy and partial pharyngectomy (N = 17), and group 3 underwent total laryngopharyngectomy with cervical esophagectomy and reconstruction (N = 11). Overall and disease-specific survivals were determined from Kaplan-Meier survival analysis. Disease-free 5-year survival in stage I and II HPCs was 40.1%. Univariate analysis showed a statistically significant decrease in survival for patients undergoing partial pharyngectomy when compared with those undergoing more extensive procedures (p < .03). This was confirmed with multivariate loglogistic regression analysis (p < .03) correcting for confounding variables of site and RT. These data suggest that wide resection improves disease-free survival in patients with early-stage HPC. 相似文献
58.
SH Belle SJ Czaja R Schulz S Zhang LD Burgio LN Gitlin R Jones AB Mendelsohn MG Ory 《Canadian Metallurgical Quarterly》2003,18(3):396-405
Researchers have examined numerous psychosocial and behavioral interventions intended to alleviate distress among family caregivers of persons with dementia. Many of these interventions are complex, combining numerous treatment components. Although some multicomponent interventions have been successful in reducing caregiver distress, the impact of specific elements of these interventions on outcomes is not known. The article presents results of an analytic approach that allows researchers to describe the individual elements of multicomponent interventions and to examine the relationships between those components and outcomes. This approach is successfully applied to interventions being evaluated in the Resources for Enhancing Alzheimer's Caregiver Health (REACH) program. The results indicate that actively targeting caregiver behavior is effective in achieving positive outcomes with respect to caregiver depression. 相似文献
59.
Older Adults Talk Technology: Technology Usage and Attitudes 总被引:2,自引:0,他引:2
Mitzner TL Boron JB Fausset CB Adams AE Charness N Czaja SJ Dijkstra K Fisk AD Rogers WA Sharit J 《Computers in human behavior》2010,26(6):1710-1721
Older adults (n = 113) participated in focus groups discussing their use of and attitudes about technology in the context of their home, work, and healthcare. Participants reported using a wide variety of technology items, particularly in their homes. Positive attitudes (i.e., likes) outnumbered negative attitudes (i.e., dislikes), suggesting that older adults perceive the benefits of technology use to outweigh the costs of such use. Positive attitudes were most frequently related to how the technology supported activities, enhanced convenience, and contained useful features. Negative attitudes were most frequently associated with technology creating inconveniences, unhelpful features, as well as security and reliability concerns. Given that older adults reported more positive than negative attitudes about the technologies they use, these results contradict stereotypes that older adults are afraid or unwilling to use technology. These findings also highlight the importance of perceived benefits of use and ease of use for models of technology acceptance. Emphasizing the benefits of technology in education and training programs may increase future technology adoption. 相似文献
60.
Because of the increased presence of computers in work and everyday life and the demographic "graying" of America, there is a need for interface designs that promote accessibility for older people. This study examined age differences in the performance of basic computer mouse control techniques. An additional goal of the study was to examine the influence of age-related changes in psychomotor abilities on mouse control. A total of 60 participants in 3 age groups (20-39 years, 40-59 years, and 60-75 years) performed 4 target acquisition tasks (pointing, clicking, double-clicking, and dragging) using a computer mouse. The data indicated that the older participants had more difficulty performing mouse tasks than the younger participants. Differences in performance attributable to age were found for the more complex tasks (clicking and double-clicking). Furthermore, age-related changes in psychomotor abilities were related to age differences in performance. We discuss applications to computer interface designs. Actual or potential applications of this research include specifications for computer mouse design to accommodate older populations. 相似文献