925 resultados para life of excitation single-state and tri-state


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本文合成了3种轴向配位的萘酞菁硅配合物(NcSiR2,R=Cl、OH、OCH3),研究了3种萘酞菁配合物激发态性质,研究结果表明.随着轴向取代基推电子能力的逐渐增强,激发单线态寿命和激发三线态寿命逐渐缩短,产生单线态氧的能力逐渐下降。

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Aphasia is a chronic acquired communication disorder that may change people with aphasia (PWA) and their caregivers’ lives for ever. Social and emotional changes are frequently reported by both, although the impact of these changes in quality of life (QOL) needs further research. This study identifies predictors and variables that influence PWA’s and their caregivers’ QOL and social relationships (SR). A cross-sectional descriptive, correlational and comparative study was undertaken with 255 individuals from Portuguese general population (mean age 43 years, range 25-84 years; 148 females, 107 males), 25 PWA (mean age 54 years, range 20-71; 12 females and 13 males), and 25 caregivers (mean age 51 years, range 26-73; 17 females and 8 males). All the participants completed the World Health Quality of Life Bref instrument, the SR domain of the World Health Organization Quality of Life – 100 scale, and the Center for Epidemiologic Studies Depression Scale. Participants with aphasia completed the Lisbon Aphasia Assessment Battery, Barthel Index, Frenchay Activities Index, Communication Disability Profile and the Modified Mini-Mental State which evaluated language disability, aphasia coefficient, activities, participation and cognition. In addition, caregivers completed the Carers’ Assessment of Managing Index to assess coping strategies. PWA and their caregivers are less satisfied with their QOL and SR than Portuguese general population; whereas PWA have the worse QOL and SR. Thus, aphasia seems to impact negatively in their QOL and SR. Emotional status has great importance for QOL and SR among the three groups. PWA’s activities and participation have great impact in both PWA’s and caregivers’ QOL and SR. Additionally, emotional status and participation are the best predictors of PWA’s QOL. Along with these two variables, activities of the PWA are the best predictors of caregivers’ QOL. Participation is the best predictor of PWA’s SR; emotional status and number of cohabitants are best predictors for caregivers’ SR. Aphasia assessment and intervention should take into account all the factors that influence PWA’s and caregivers’ QOL and SR so the central goal of enhancing it can be achieved. These results are important for identifying and planning support needs and are useful in the orientation of the activities carried out by the service providers allowing the adjustment of health programs and policies based on people’s real life needs.

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The SLC13 family comprises five genes (SLC13A1, SLC13A2, SLC13A3, SLC13A4, and SLC13A5) encoding structurally related multi-spanning transporters (8-13 transmembrane domains) with orthologues found in prokaryotes and eukaryotes. Mammalian SLC13 members mediate the electrogenic Na(+)-coupled anion cotransport at the plasma membrane of epithelial cells (mainly kidney, small intestine, placenta and liver) or cells of the central nervous system. While the two SLC13 cotransporters NaS1 (SLC13A1) and NaS2 (SLC13A4) transport anions such sulfate, selenate and thiosulfate, the three other SLC13 members, NaDC1 (SLC13A2), NaCT (SLC13A5) and NaDC3 (SLC13A3), transport di- and tri-carboxylate Krebs cycle intermediates such as succinate, citrate and α-ketoglutarate. All these transporters play a variety of physiological and pathophysiological roles in the different organs. Thus, the purpose of this review is to summarize the roles of SLC13 members in human physiology and pathophysiology and what the therapeutic perspectives are. We have also described the most recent advances on the structure, expression, function and regulation of SLC13 transporters.

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A study undertaken in Hervey Bay, Queensland, investigated the potential of creating an indigenous agribusiness opportunity based on the cultivation of indigenous Australian vegetables and herbs. Included were warrigal greens (WG) (Tetragonia tetragonioides), a green leafy vegetable and the herb sea celery (SC) (Apium prostratum); both traditional foods of the indigenous population and highly desirable to chefs wishing to add a unique, indigenous flavour to modern dishes. Packaging is important for shelf life extension and minimisation of postharvest losses in horticultural products. The ability of two packaging films to extend WG and SC shelf life was investigated. These were Antimisted Biaxial Oriented Polypropylene packaging film (BOPP) without perforations and Antifog BOPP Film with microperforations. Weight loss, packaging headspace composition, colour changes, sensory differences and microbial loads of packed WG and SC leaves were monitored to determine the impact of film oxygen transmission rate (OTR) and film water vapour transmission (WVT) on stored product quality. WG and SC were harvested, sanitised, packed and stored at 4°C for 16 days. Results indicated that the OTR and WVT rates of the package film significantly (PKLEINERDAN0.05) influenced the package headspace and weight loss, but did not affect product colour, total bacteria, yeast and mould populations during storage. There was no significant difference (PGROTERDAN0.05) in aroma, appearance, texture and flavour for WG and SC during storage. It was therefore concluded that a shelf life of 16 days at 4°C, where acceptable sensory properties were retained, was achievable for WG and SC in both packaging films.

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Frozen storage characteristics and shelflife vary considerably among species as well as within the species (Powrie, 1973; Fennema. 1973). This can be attributed to the variation in the composition of fish among various species. In certain species like sardines and mackerel. wide seasonal variation in chemical composition occur within the species. These variations affect the quality and shelflife. The nutritional level of water. spawning, method of catching, struggling etc. are found to have profound influence on the condition of the fresh fish. Soon after death the deteriorative changes in fish start due to autolysis and bacterial growth. The rate of these changes depends mainly on temperature. The handling methods have great influence on bacterial contamination. Thus the type oi'handling. temperature control. period of chill storage. processing methods. type of freezing, condition of frozen storage and period of storage affect the quality and shelflife Of the fisho In the present study extensive investigations were carried out on various factors affecting the quality of fish as well as their effect on the physical. chemical and sensory qualities of fish during frozen storage and the shelflife

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Objective:To identify aspects that affect the quality of life of nursing caregivers and their relationship with care in an Intensive Care Unit for Adults (A-ICU). Methods:This was a descriptive study with qualitative approach, taking as subjects 21 professionals who constitute the nursing staff of the A-ICU of a school hospital in Maringá-PR. Unstructured interview was used as a strategy to collect data, conducted between May and June 2009. Data analysis was based on the method of content analysis. The categories identified were: overlooking improvement in quality of life related to the resources in an A-ICU; the quality of life influencing the form of care; interpersonal relationships into the health team reflecting on the quality of life and care. Results:The analysis of caregivers’ speech and the results of the observation showed that there is correlation between the aspects they consider influential in their quality of life and the way of caring for patients in an A-ICU.Conclusion: The findings indicate that, among the influential aspects, the stressful factors overlap the enhancing ones. From this perspective, dealing with caregiver’s suffering might be the starting point for the improvement in quality of care in an A-ICU.

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Statement of problem. Removable partial dentures are affected by fatigue because of the cyclic mechanism of the masticatory system ansi frequent insertion and removal. Titanium and its alloys have been used in the manufacture of denture frameworks; however, preventive agents with fluorides are thought to attack titanium alloy surfaces.Purpose. This study evaluated, compared, analyzed the corrosion-fatigue life of commercially pure titanium and Ti-6Al-4V alloy in different storage environments.Material and methods. For each metal, 33 dumbbell rods, 2.3 mm in diameter at the central segment, were cast in the Rematitan system. Corrosion-fatigue strength test was carried out through a universal testing machine with a load 30% lon er than the 0.2% offset yield strength and a combined influence of different: environments: in air at room temperature, with synthetic saliva, and with fluoride synthetic saliva. After failure, the number of cycles were recorded, and fracture surfaces were examined with on SEM.Results. ANOVA and Tukey's multiple comparison rest indicated that Ti-6Al-4V alloy achieved 21,269 cycles (SD = 8,355) against 19,157 cycles (SD = 3,624) for the commercially purr Ti. There were no significant differences between either metal in the corrosion-fatigue life for dry specimens, but when the solutions were present, the fatigue life was significantly reduced, probably because of the product-ion of corrosion pits caused by superficial reactions.

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Treatment of metastatic breast cancer with doxorubicin (Doxo) in combination with trastuzumab, an antibody targeting the ErbB2 receptor, results in an increased incidence of heart failure. Doxo therapy induces reactive oxygen species (ROS) and alterations of calcium homeostasis. Therefore, we hypothesized that neuregulin-1 beta (NRG), a ligand of the cardiac ErbB receptors, reduces Doxo-induced alterations of EC coupling by triggering antioxidant mechanisms. Adult rat ventricular cardiomyocytes (ARVM) were isolated and treated for 18-48 h. SERCA protein was analyzed by Western blot, EC coupling parameters by fura-2 and video edge detection, gene expression by RT-PCR, and ROS by DCF-fluorescence microscopy. At clinically relevant doses Doxo reduced cardiomyocytes contractility, SERCA protein and SR calcium content. NRG, similarly as the antioxidant N-acetylcystein (NAC), did not affect EC coupling alone, but protected against Doxo-induced damage. NRG and Doxo showed an opposite modulation of glutathione reductase gene expression. NRG, similarly as NAC, reduced peroxide- or Doxo-induced oxidative stress. Specific inhibitors showed, that the antioxidant action of NRG depended on signaling via the ErbB2 receptor and on the Akt- and not on the MAPK-pathway. Therefore, NRG attenuates Doxo-induced alterations of EC coupling and reduces oxidative stress in ARVM. Inhibition of the ErbB2/NRG signaling pathway by trastuzumab in patients concomitantly treated with Doxo might prevent beneficial effects of NRG in the myocardium.

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The large discrepancy between field and laboratory measurements of mineral reaction rates is a long-standing problem in earth sciences, often attributed to factors extrinsic to the mineral itself. Nevertheless, differences in reaction rate are also observed within laboratory measurements, raising the possibility of intrinsic variations as well. Critical insight is available from analysis of the relationship between the reaction rate and its distribution over the mineral surface. This analysis recognizes the fundamental variance of the rate. The resulting anisotropic rate distributions are completely obscured by the common practice of surface area normalization. In a simple experiment using a single crystal and its polycrystalline counterpart, we demonstrate the sensitivity of dissolution rate to grain size, results that undermine the use of "classical" rate constants. Comparison of selected published crystal surface step retreat velocities (Jordan and Rammensee, 1998) as well as large single crystal dissolution data (Busenberg and Plummer, 1986) provide further evidence of this fundamental variability. Our key finding highlights the unsubstantiated use of a single-valued "mean" rate or rate constant as a function of environmental conditions. Reactivity predictions and long-term reservoir stability calculations based on laboratory measurements are thus not directly applicable to natural settings without a probabilistic approach. Such a probabilistic approach must incorporate both the variation of surface energy as a general range (intrinsic variation) as well as constraints to this variation owing to the heterogeneity of complex material (e.g., density of domain borders). We suggest the introduction of surface energy spectra (or the resulting rate spectra) containing information about the probability of existing rate ranges and the critical modes of surface energy.