1000 resultados para ddc: 005.74


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The ability to quickly detect and respond to visual stimuli in the environment is critical to many human activities. While such perceptual and visual-motor skills are important in a myriad of contexts, considerable variability exists between individuals in these abilities. To better understand the sources of this variability, we assessed perceptual and visual-motor skills in a large sample of 230 healthy individuals via the Nike SPARQ Sensory Station, and compared variability in their behavioral performance to demographic, state, sleep and consumption characteristics. Dimension reduction and regression analyses indicated three underlying factors: Visual-Motor Control, Visual Sensitivity, and Eye Quickness, which accounted for roughly half of the overall population variance in performance on this battery. Inter-individual variability in Visual-Motor Control was correlated with gender and circadian patters such that performance on this factor was better for males and for those who had been awake for a longer period of time before assessment. The current findings indicate that abilities involving coordinated hand movements in response to stimuli are subject to greater individual variability, while visual sensitivity and occulomotor control are largely stable across individuals.

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The present study aims to identify the framework of personal, organizational and technical variables that contribute to the viability and successful of innovative educational practices with video games within the school context to enhance the multiple intelligences. For this purpose, advantage was taken on the information previously collected through a questionnaire about the views, thoughts and experiences of a group of teachers of childhood and primary education (N=25) who voluntarily participated in a blended training activity from Center of Teachers (CEFIRE) of Valencia, around a community of practice aimed at promoting and advising projects for implementing educational video games in the classroom. The mixed methodology adopted has allowed the following: a) describe the relationship between their degree of development and daily use made of ICT in the classroom, their level of familiarity with video games,  their previous experience to integrate them for educational purposes..., and their participation in projects that focus on game-based learning; b) conduct content analysis of the opinions and thoughts expressed in a forum for teachers on innovation on and methodological strategies adopted reflected in a virtual board; and c) develop a SWOT analysis: Strengths, Weaknesses, Opportunities and Threats inherent in the implementation of experience with video games in the classroom. Among the conclusions, it is highlighted that, even though most did not have specific training or enough technological resources and the planning and implementation of innovation required them a great investment of time, their personal interest, the support given by members of the online community of practice, helped to encourage their activity, along with receptivity, positive attitude and high motivation of students with the experience. These aspects have been crucial to promote successful innovative practices with video games.

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Los avances que están produciéndose en el ámbito académico con el surgimiento de herramientas de la Web 2.0 y el empleo masivo por parte de los estudiantes de la redes sociales para comunicarse entre ellos, está haciendo que el panorama educativo se encuentre ante unos desafíos a los que tiene que dar respuesta. La investigación que aquí se presenta tuvo como objetivo principal analizar el estado del empleo de la redes sociales por parte alumnado universitario, así como los posibles malos hábitos y usos problemáticos de las mismas. Se utilizó como instrumento de recogida de información un cuestionario “ad hoc” con un total de 23 ítems. Se concluye que el alumnado en general no posee malos hábitos en el empleo de las redes sociales, igualmente los resultados obtenidos ponen de manifiesto que su utilización no está plenamente integrada en las instituciones universitarias de educación superior, así como que los estudiantes no las emplean/usan como herramienta fundamental para las resolución de cuestiones académicas.

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Background & Aims: Alcohol consumption may increase gastroesophageal reflux symptoms, cause damage to the esophageal mucosa, and/or promote carcinogenesis. However, reports about the association between alcohol and reflux esophagitis, Barrett's esophagus, and esophageal adenocarcinoma are conflicting. Methods: Information relating to alcohol consumption, at age 21 and 5 years before the interview date, was collected from 230 reflux esophagitis, 224 Barrett's esophagus, and 227 esophageal adenocarcinoma patients and 260 frequency-matched population controls. Logistic regression analyses were used to compare alcohol consumption in the 3 case groups to controls with adjustment for potential confounders. Results: Population controls reporting gastroesophageal reflux symptoms were less likely than controls without symptoms to drink alcohol 5 years before the interview date (odds ratio [OR], 0.44, 0.20-0.99). No associations were observed between total alcohol consumption 5 years before the interview date and reflux esophagitis, Barrett's esophagus, or esophageal adenocarcinoma (OR, 1.26, 0.78-2.05; OR, 0.72, 0.43-1.21; and OR, 0.75, 0.46-1.22, respectively). Wine was inversely associated with reflux esophagitis (OR, 0.45, 0.27-0.75). Total alcohol consumption at age 21 years was significantly associated with reflux esophagitis (OR, 2.24, 1.35-3.74) but not with Barrett's esophagus or esophageal adenocarcinoma (OR, 1.06, 0.63-1.79 and OR, 1.27, 0.77-2.10, respectively). Conclusions: Alcohol consumption in early adulthood may lead to the development of reflux esophagitis. More recent alcohol consumption does not appear to confer any increased risk of reflux esophagitis, Barrett's esophagus, or esophageal adenocarcinoma. In fact, wine consumption may reduce the risk of these 3 esophageal disorders.

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PURPOSE. Advanced glycation end products (AGES) form irreversible cross- links with many macromolecules and have been shown to accumulate in tissues at an accelerated rate in diabetes. In the present study, AGE formation in vitreous was examined in patients of various ages and in patients with diabetes. Ex vivo investigations were performed on bovine vitreous incubated in glucose to determine AGE formation and cross-linking of vitreous collagen. METHODS. By means of an AGE-specific enzyme-linked immunosorbent assay (ELISA), AGE formation was investigated in vitreous samples obtained after pars plana vitrectomy in patients with and without diabetes. In addition, vitreous AGES were investigated in bovine vitreous collagen after incubation in high glucose, high glucose with aminoguanidine, or normal saline for as long as 8 weeks. AGEs and AGE cross-linking was subsequently determined by quantitative and qualitative assays. RESULTS. There was a significant correlation between AGEs and increasing age in patients without diabetes (r = 0.74). Furthermore, a comparison between age-matched diabetic and nondiabetic vitreous showed a significantly higher level of AGEs in the patients with diabetes (P < 0.005). Collagen purified from bovine vitreous incubated in 0.5 M glucose showed an increase in AGE formation when observed in dot blot analysis, immunogold labeling, and AGE ELISA. Furthermore, there was increased cross-linking of collagen in the glucose-incubated vitreous, when observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and protein separation. This cross-linking was effectively inhibited by coincubation with 10 mM aminoguanidine. CONCLUSIONS. This study suggests that AGEs may form in vitreous with increasing age. This process seems to be accelerated in the presence of diabetes and as a consequence of exposure to high glucose. Advanced glycation and AGE cross-linking of the vitreous collagen network may help to explain the vitreous abnormalities characteristic of diabetes.

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Background: Anaerobic bacteria are increasingly regarded as important in cystic fibrosis (CF) pulmonary infection. The aim of this study was to determine the effect of antibiotic treatment on aerobic and anaerobic microbial community diversity and abundance during exacerbations in patients with CF.

Methods: Sputum was collected at the start and completion of antibiotic treatment of exacerbations and when clinically stable. Bacteria were quantified and identified following culture, and community composition was also examined using culture-independent methods.

Results: Pseudomonas aeruginosa or Burkholderia cepacia complex were detected by culture in 24/26 samples at the start of treatment, 22/26 samples at completion of treatment and 11/13 stable samples. Anaerobic bacteria were detected in all start of treatment and stable samples and in 23/26 completion of treatment samples. Molecular analysis showed greater bacterial diversity within sputum samples than was detected by culture; there was reasonably good agreement between the methods for the presence or absence of aerobic bacteria such as P aeruginosa (kappa=0.74) and B cepacia complex (kappa=0.92), but agreement was poorer for anaerobes. Both methods showed that the composition of the bacterial community varied between patients but remained relatively stable in most individuals despite treatment. Bacterial abundance decreased transiently following treatment, with this effect more evident for aerobes (median decrease in total viable count 2.3 x 10(7) cfu/g, p=0.005) than for anaerobes (median decrease in total viable count 3 x 10(6) cfu/g, p=0.046).

Conclusion: Antibiotic treatment targeted against aerobes had a minimal effect on abundance of anaerobes and community composition, with both culture and molecular detection methods required for comprehensive characterisation of the microbial community in the CF lung. Further studies are required to determine the clinical significance of and optimal treatment for these newly identified bacteria.

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The dimerisation of cyclooctene (COE) to 1,9-cyclohexadecadiene, a molecule of interest to the fragrance industry, has been achieved using ruthenium catalysts in organic solvents with significantly better selectivities (47-74%) and yields (39-60%) than previously reported (34% and 30%, respectively). Grubbs' first and second generation catalysts, the Hoveyda-Grubbs' catalyst and a phosphonium alkylidene catalyst were tested in a range of organic solvents and ionic liquids (ILs), including 1:1 IL/dichloromethane mixtures and biphasic IL + pentane systems. The best results (74% selectivity, 60% yield) were obtained using Grubbs' first generation catalyst in 1,2-dichloroethane. The formation of trimer, tetramer and other higher molecular mass products were found to be favoured at low catalyst loadings (0.77 mM). Studies of metathesis reactions using 1,9-cyclohexadecadiene as substrate indicated that the monomer-dimer and monomer-trimer reactions are faster than the dimer-dimer reaction. The use of IL media allowed for the recyclability of the catalyst, although a drop in the yield of dimer generally occurred after the first run. Heterogeneized catalysts, where the IL-catalyst system was immobilised onto silica, resulted in fast reactions leading to poor yields of dimer. (C) 2011 Elsevier B.V. All rights reserved.

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The kinetics of photomineralization of 4-chlorophenol (4-CP) sensitized by Degussa P25 TiO2 in O2-saturated solution is studied as a function of the following different experimental parameters: pH, [TiO2], percentage O2 [O2], [4-CP], T, I, lambda and [KNO3]. At pH 2 and T=30-degrees-C the initial relative rate of CO2 photogeneration R(CO2) conforms to a Langmuir-Hinshelwood-type kinetic scheme and the relationship between R(CO2) and the various experimental parameters may be summarized as follows: R(CO2) = gammaK(O2)[O2](I(a))(theta)K(4-CP]0/(1 + K(O2])(1 + K(4-CP)[4-CP]0) where gamma is a proportionality constant, K(O2) = 0.044 +/- 0.005[O2]-1, theta = 0.74 +/- 0.05 and K(4-CP) = (29 +/- 3) x 10(3) dm3 mol-1. The overall activation energy for this photosystem was determined as 16 +/- 2 kJ mol-1. This work forms part of an overall characterization study in which it is proposed that the 4-CP-TiO2-O2 photosystem is adopted as a standard test system for incorporation into all future semiconductor-sensitized photomineralization studies in order to facilitate comparisons between the results of the different studies.

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Better treatment is required for older patients with acute myeloid leukemia (AML) not considered fit for intensive chemotherapy. We report a randomized comparison of lowdose Ara-C (LDAC) vs the novel nucleoside, clofarabine, in untreated older patients with AML and high-risk myelodysplastic syndrome (MDS). A total of 406 patients with de novo (62%), secondary disease (24%), or high-risk MDS (>10% marrow blasts) (15%), median age 74 years, were randomized to LDAC 20 mg twice daily for 10 days every 6 weeks or clofarabine 20 mg/m2 on days 1 to 5, both for up to 4 courses. These patients had more adverse demographics than contemporaneous intensively treated patients. The overall remission rate was 28%, and 2-year survival was 13%. Clofarabine significantly improved complete remission (22% vs 12%; hazard ratio [HR] 5 0.47 [0.28-0.79]; P 5 .005) and overall response (38% vs 19%; HR 5 0.41 [0.26-0.62]; P < .0001), but there was no difference in overall survival, explained by poorer survival in the clofarabine patients who did not gain complete remission and also following relapse. Clofarabine was more myelosuppressive and required more supportive care. Although clofarabine doubled remission rates, overall survival was not improved overall or in any subgroup. The treatment of patients of the type treated here remains a major unmet need. This trial was registered at www.clinicaltrials.gov as #ISRCTN 11036523.

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PURPOSE: To model the possible impact of using average-power intraocular lenses (IOLs) and evaluate the postoperative refractive error in patients having cataract surgery in rural China.SETTING: Rural Guangdong, China.METHODS: Patients having cataract surgery by local surgeons were examined and visual function was assessed 10 to 14 months after surgery. Subjective refraction at near and distance was performed bilaterally by an ophthalmologist. Patients had a target refraction of -0.50 diopter (D) based on ocular biometry.RESULTS: Of the 313 eligible patients, 242 (77%) could be contacted and 176 (74% of contacted patients, 56% overall) were examined. Examined patients had a mean age of 69.4 +/- 10.5 years. Of the 211 operated eyes, 73.2% were within +/-1.0 D of the target refraction after surgery. The best presenting distance vision was in patients within +/-1.0 D of plano and the best presenting near vision, in those with mild myopia (<-1.0 D to > or =2.0 D) (P= .005). However, patients with hyperopia (>+1.0 D) reported significantly better adjusted visual function than those with emmetropia or myopia (<-1.0 D). When the predicted use of an average-power IOL (median +21.5 D) was modeled, predicted visual acuity was significantly reduced (P= .001); however, predicted visual function was not significantly altered (P>.3).CONCLUSIONS: Accurate selection of postoperative refractive error was achieved by local surgeons in this rural area. Based on visual function results, aiming for mild postoperative myopia may not be suitable in this setting. Implanting average-power IOLs significantly reduced postoperative presenting vision, but not visual function.

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Es gilt nicht nur für die Frauen aus den Fesseln der Liebe und die Liebe aus den Fesseln der Familie, sondern auch die Humanität, d.h. die Regelung menschlicher Belange, sowie die Geschlechtersolidarität aus den Fesseln von Familie zu befreien. Um der Konstitution der Selbstverständlichkeit von Familie auf die Spur zu kommen, geht die Autorin zurück bis ins 18. Jahrhundert und analysiert bürgerliche und sozialistische Ansätze aus Theorie, Politik und Literatur: Was gewannen Frauen, als sie sich auf die jeweilige Familienform einließen, und was versperrten sie sich dadurch? Welche geschlechtsspezifische Funktion kam dabei Liebe als einem Hauptmotiv für Eheschließung und Familiengründung zu? An Hand eimer qualitativen Studie wird abschließend vorgeführt, inwiefern die unterschiedlichen Liebeskonstruktionen von Frauen (und Männern) heute zur Reproduktion der Geschlechterverhältnisse beitragen.