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91.
Schulz Richard; Czaja Sara J.; Lustig Amy; Zdaniuk Bozena; Martire Lynn M.; Perdomo Dolores 《Canadian Metallurgical Quarterly》2009,54(1):1
Objective: To assess the efficacy of two psychosocial interventions for caregivers of older persons with spinal cord injury (SCI). Design: A multisite, three-group, randomized controlled trial comparing two active intervention conditions with each other and to an information-only control group. One hundred seventy-three caregiver and care-recipient dyads were randomly assigned to one of three conditions: a caregiver-only treatment condition in which caregivers received a multicomponent intervention based on their risk profile; a dual-target condition in which the caregiver intervention was complemented by a treatment targeting the care recipient, designed to address both caregiver and care recipient risk factors; and an information-only control condition in which the caregiver received standard printed information about caregiving, SCI, and aging. Outcome Measures: A multivariate outcome comprised of six indicators linked to the goals of the interventions was the primary outcome of the study. The multivariate outcome included measures of depressive symptoms, burden, social support and integration, self-care problems, and physical health symptoms. Results: At 12 months, caregivers in the dual-target condition had improved quality of life as measured by our multivariate outcome when compared to the control condition. Using the dyad as the unit of analysis, the dual-target condition was superior to both the control condition and the caregiver-only condition in our multivariate outcomes analysis. Dyads enrolled in the dual-target condition had significantly fewer health symptoms than control condition and caregiver-only condition participants and were less depressed when compared to participants in the caregiver-only condition. In follow-up analyses we found that a higher proportion of caregivers in the dual-target condition had clinically significant improvements in depression, burden, and health symptoms when compared with the caregiver-only condition. Conclusion: Caregivers are in need of and can benefit from interventions that help them manage the medical and functional limitations of the care recipient. Intervention strategies that target both the caregiver and care recipient are particularly promising strategies for improving the quality of life of caregivers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
Biological activation of carbon filters 总被引:6,自引:0,他引:6
To prepare biological activated carbon (BAC), raw surface water was circulated through granular activated carbon (GAC) beds. Biological activity of carbon filters was initiated after about 6 months of filter operation and was confirmed by two methods: measurement of the amount of biomass attached to the carbon and by the fluorescein diacetate (FDA) test. The effect of carbon pre-washing on WG-12 carbon properties was also studied. For this purpose, the nitrogen adsorption isotherms at 77K and Fourier transform-infrared (FT-IR) spectra analyses were performed. Moreover, iodine number, decolorizing power and adsorption properties of carbon in relation to phenol were studied. Analysis of the results revealed that after WG-12 carbon pre-washing its BET surface increased a little, the pH value of the carbon water extract decreased from 11.0 to 9.4, decolorizing power remained at the same level, and the iodine number and phenol adsorption rate increased. In preliminary studies of the ozonation-biofiltration process, a model phenol solution with concentration of approximately 10mg/l was applied. During the ozonation process a dose of 1.64 mg O(3)/mg TOC (total organic carbon) was employed and the contact time was 5 min. Four empty bed contact times (EBCTs) in the range of 2.4-24.0 min were used in the biofiltration experiment. The effectiveness of purification was measured by the following parameters: chemical oxygen demand (COD(Mn)), TOC, phenol concentration and UV(254)-absorbance. The parameters were found to decrease with EBCT. 相似文献
93.
Ewa Schab‐Balcerzak Mariola Siwy Bozena Jarzabek Anna Kozanecka‐Szmigiel Krzysztof Switkowski Bronisław Pura 《应用聚合物科学杂志》2011,120(2):631-643
This paper reports novel photoresponsive, processable poly(esterimide)s functionalized with the azobenzene and tricyanovinylene groups. Post and prepolymerization strategies were utilized for preparation of the new photochromic polymers with imide rings. The postpolymerization method of azopolymer synthesis included a functionalization of precursor poly(esterimide) containing dialkylaminophenyl groups with diazonium salt of aniline. The precursor poly(esterimide) was obtained from synthesized 2,2′[N‐phenylethyloaniline‐di(4‐estro‐1,2‐dicarboxylic)]anhydride and 4,4′‐methylene bis(2,6‐dimethylaniline). The prepolymerization strategy based on polycondesation of 2,4‐diaminoazobenzene with two dianhydrides, that is, with or without the azobenzene group. The new dianhydride with azobenzene unit was obtained. The reaction of post‐tricyanovinylation was carried out for substitution of prepared polymers with tricyanovinylene groups. The synthesized polymers were characterized and evaluated by FTIR, 1H NMR, X‐ray, UV‐Vis spectroscopies, and DSC. The polymers exhibited glass transition temperatures in the range of 119–208°C and good solubilities in common organic solvents, providing optical‐quality films. Thermal stability of the polymers films was investigated by UV‐Vis spectroscopy. Preliminary investigations of the optical anisotropy in chosen poly(esterimide)s were carried out by photoinduced birefringence measurements. Relatively high photoinduced birefringence (Δn = 0.01) was measured for polyimide with covalently bonded azobenzene substituted with strong acceptor group. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
94.
Maria Urbanova Verona Buocikova Lenka Trnkova Sabina Strapcova Viera Horvathova Kajabova Emma Barreto Melian Maria Novisedlakova Miroslav Tomas Peter Dubovan Julie Earl Jozef Bizik Eliska Svastova Sona Ciernikova Bozena Smolkova 《International journal of molecular sciences》2022,23(4)
Due to abundant stroma and extracellular matrix, accompanied by lack of vascularization, pancreatic ductal adenocarcinoma (PDAC) is characterized by severe hypoxia. Epigenetic regulation is likely one of the mechanisms driving hypoxia-induced epithelial-to-mesenchymal transition (EMT), responsible for PDAC aggressiveness and dismal prognosis. To verify the role of DNA methylation in this process, we assessed gene expression and DNA methylation changes in four PDAC cell lines. BxPC-3, MIA PaCa-2, PANC-1, and SU.86.86 cells were exposed to conditioned media containing cytokines and inflammatory molecules in normoxic and hypoxic (1% O2) conditions for 2 and 6 days. Cancer Inflammation and Immunity Crosstalk and Human Epithelial to Mesenchymal Transition RT² Profiler PCR Arrays were used to identify top deregulated inflammatory and EMT-related genes. Their mRNA expression and DNA methylation were quantified by qRT-PCR and pyrosequencing. BxPC-3 and SU.86.86 cell lines were the most sensitive to hypoxia and inflammation. Although the methylation of gene promoters correlated with gene expression negatively, it was not significantly influenced by experimental conditions. However, DNA methyltransferase inhibitor decitabine efficiently decreased DNA methylation up to 53% and reactivated all silenced genes. These results confirm the role of DNA methylation in EMT-related gene regulation and uncover possible new targets involved in PDAC progression. 相似文献
95.
Barbara Maliszewska-Kordybach Bozena Smreczak Agnieszka Klimkowicz-Pawlas 《The Science of the total environment》2009,407(12):3746-3753
Soils from agricultural areas receive unsatisfactory attention as regards the contamination with organic pollutants. To answer those needs the contents of the sixteen individual PAH compounds were determined (GC/MS technique) in agricultural soils in Poland. The samples (n = 216) were collected from the upper layer of arable land in the year 2005. Half of the samples represented typical rural areas, while the rest derived from the territories potentially subjected to the urban/industrial pressure of various intensity. The mean (geometric) content of individual compounds varied from 1 μg kg− 1 for acenaphtylene to 55 μg kg− 1 for fluoranthene with the highest contributions (11.6%-12.9%) of phenanthrene, fluoranthene and pyrene. Higher molecular weight PAHs (4 rings) were strongly linked mutually and with the ∑16PAHs. They contributed substantially (73%) to the overall content of PAHs, which implies domination of anthropogenic sources. The calculated molecular indexes suggest that most of those PAHs derive from the combustion of coal, the main energy source in Poland. Simultaneously, the concentrations of lower molecular weight compounds seem to reflect the background, “natural” PAH compounds, which represent mainly atmospherically distributed emission. The division of the samples into groups describing geographical regions and landscape type enabled evaluation of the spatial trends in contamination of soils with PAH compounds. The most pronounced effect of spatial parameters corresponded to PAHs > 4 rings, while lower molecular weight compounds showed more homogeneous concentration through the country. 相似文献
96.
Magdalena Senderowicz Teresa Nowak Hanna Weiss-Schneeweiss Laszlo Papp Bozena Kolano 《International journal of molecular sciences》2022,23(7)
Although Crepis was the first model plant group in which chromosomal changes were considered to play an important role in speciation, their chromosome structure and evolution have been barely investigated using molecular cytogenetic methods. The aim of the study was to provide a better understanding of the patterns and directions of Crepis chromosome evolution, using comparative analyses of rDNA loci number and localisation. The chromosome base number and chromosomal organisation of 5S and 35S rDNA loci were analysed in the phylogenetic background for 39 species of Crepis, which represent the evolutionary lineages of Crepis sensu stricto and Lagoseris, including Lapsana communis. The phylogenetic relationships among all the species were inferred from nrITS and newly obtained 5S rDNA NTS sequences. Despite high variations in rDNA loci chromosomal organisation, most species had a chromosome with both rDNA loci within the same (usually short) chromosomal arm. The comparative analyses revealed several independent rDNA loci number gains and loci repositioning that accompanied diversification and speciation in Crepis. Some of the changes in rDNA loci patterns were reconstructed for the same evolutionary lineages as descending dysploidy. 相似文献
97.
98.
The role of computers in school education is briefly discussed. Multimodal interfaces development history is shortly reviewed. Examples of applications of multimodal interfaces for learners with special educational needs are presented, including interactive electronic whiteboard based on video image analysis, application for controlling computers with facial expression and speech stretching audio interface representing audio modality. Intelligent and adaptive algorithms applications to the developed multimodal interfaces are discussed. 相似文献
99.
Mariana‐Dana Damaceanu Bozena Jarzabek Maria Bruma 《Polymer Engineering and Science》2014,54(5):1126-1133
Two series of polymers and copolymers containing oxadiazole units have been studied with respect to their photo‐optical and electrochemical behavior. Fluorene units were introduced in the macromolecular chain together with oxadiazole rings in order to obtain a better balance between electrons and holes injection and transporting properties. Upon irradiation with UV light the polymers showed photoluminescence maxima in the blue spectral range. Cyclic voltammetry was performed in order to obtain information about the electrochemical stability and reversibility of the redox processes of these polyoxadiazoles. The highest occupied molecular orbital and lowest unoccupied molecular orbital energy levels, and electrochemical and optical band gap values were calculated by using the results of cyclic voltammetry and UV/vis spectroscopy, respectively, showing very good electron injection and transport characteristics. POLYM. ENG. SCI., 54:1126–1133, 2014. © 2013 Society of Plastics Engineers 相似文献
100.
The paper presents the mechanism of lactide polymerization initiated with zinc (II) acetylacetonate monohydrate. However, the actual initiator of this reaction is the complex containing a metal-oxygen bond, formed by the exchange reaction of acetylacetonate ligand with deprotonated lactide derivative. The described reaction results in the release of free acetylacetonate and formation of transitional zinc complex with metal-oxygen bond connecting the zinc atom with derivative of lactide, incorporated - as a new, active in polymerization ligand. Polylactide chain propagation process, which constitutes the following stage of the reaction, is caused by a typical, well known, coordination-insertion ring opening polymerization. The proceeding polymerization maximum yield at the applied conditions does not exceed about 70% in benzene solution and 90% at bulk. 相似文献