1,262 research outputs found
Maltrato infantil y representaciones de apego: defensas, memoria y estrategias, una revisión
Rodriguez, AF (Fresno Rodriguez, Andres); Contreras, RS (Spencer Contreras, Rosario); Castro, TR (Retamal Castro, Tania). Univ Talca, Fac Psicol, Talca, Chile.The aim of this paper is a review of the literature about the influence of child abuse on the formation of attachment representations. It describes the main theoretical assumptions about the effects of abuse on the defensive processes, memory systems and attachment strategies. These elements are discussed trough the presentation of an integrative model which is contrasted with empirical studies. It shows that child abuse affects the quality of attachment representations; however the studies do not take in to account all the complexity of the phenomenon of abuse. Theoretical issues discussed in this paper are marginally tested in the research reported
Phacoemulsification of the crystalline lens and implantation of an intraocular lens for the correction of moderate and high myopia: Four-year follow-up
Purpose: To assess the safety of lens extraction and intraocular lens (IOL) implantation in patients with high myopia treated for initial lens opacity and/or refractive indications. Setting: Instituto de Microcirugfa Ocular de Barcelona, Barcelona, Spain. Methods: This retrospective nonrandomized case series study comprised 44 eyes of 30 consecutive myopic patients who had surgery because of initial lens opacity and/or refractive indications during a 2-year period. In each case, phacoemulsification was performed using an ultrasonic technique and an IOL was implanted in the capsular bag. The patients were seen preoperatively to evaluate retinal pathology. They also had a complete ophthalmologic evaluation that included detailed indirect ophthalmoscopy. All patients were followed at regular intervals. The main outcome measures were preoperative and postoperative-spherical equivalent (SE), the incidence of posterior capsule opacification (PCO) and the need for capsulotomy, and the incidence of retinal complications. Results: In all eyes, the surgery was uneventful. The mean patient age at surgery was 42.83 years; the mean preoperative SE was -15.77 diopters (D) and the mean postoperative SE, -1.05 D. No eye required preoperative peripheral retinal photocoagulation. Twenty-five eyes (56.8%) had PCO and had a neodymium:YAG laser capsulotomy. One eye had a retinal tear 14 months after surgery and was treated with focal photocoagulation. The mean endothelial cell loss was 2.1% during the first postoperative year. Two eyes had an immediate postoperative intraocular pressure (IOP)rise, 1 with an inflammatory membrane and the other with corneal edema; both resolved with topical treatment. One eye with elevated IOP and a bad response to medical treatment had argon laser trabeculoplasty. No eye had a retinal detachment during the follow-up. Conclusion: With a thorough preoperative ophthalmologic evaluation and uneventful surgery, patients who have phacoemulsification and IOL implantation for the correction of myopia have a satisfactory chance of obtaining good visual results with few complications. ©2003 ASCRS and ESCRS
Using a hybrid approach for the development of an ontology in the hydrographical domain
This work presents a hybrid approach for domain ontology development, which
merges top-down and bottom-up techniques. In the top-down approach the concepts
in the ontology are derived from an analysis and study of relevant information
sources about the domain (e.g., hydrographic features). In the bottom-up approach
the concepts in the ontology are the result of applying formal methods on a analysis
of the data instances on the repositories (e.g., repositories containing hydrographical
features)
Modelo de Interoperabilidad Basado en Metadatos (MIBM)
Un objetivo fundamental de las Infraestructuras de Datos Espaciales (IDE) es dotar de interoperabilidad a los sistemas que han de intercambiar datos geográficos. La interoperabilidad es, en sí misma, un objetivo, así como lo es el análisis y la medida del grado de interoperabilidad entre dos sistemas. Tanto en el campo de los Sistemas de Información Geográfica (SIG) [1] como en el de la ingeniería del software [2] o el de las organizaciones, se ha estudiado la interoperabilidad y se han propuesto modelos de la misma para los sistemas, las organizaciones y los sistemas de sistemas. En el contexto de las IDE no se ha desarrollado apenas investigación relacionando la interoperabilidad y los metadatos de la Información Geográfica. Los objetivos de este documento son: presentar un modelo de interoperabilidad de 7 niveles (técnica, sintáctica, semántica, pragmática, dinámica, conceptual y organizacional) así como los resultados de analizar las aportaciones, en términos de interoperabilidad, de los ítems contenidos en ISO19115 [3] según dicho modelo. Se concluye este trabajo enumerando una serie de conclusiones preliminares obtenidas de la validación
Assessment of toxicity and biodegradability on activated sludge of priority and emerging pollutants
Several methods for evaluating the toxicity and biodegradability of hazardous pollutants (chlorinated compounds, chemical additives and pharmaceuticals) have been studied in this work. Different bioassays using representative bacteria of marine and terrestrial ecosystems such as Vibrio fischeri and Pseudomonas putida have been used to assess the ecotoxicity. Activated sludge was used to analyse the effect of those pollutants in a biological reactor of a sewage treatment plant (STP). The results demonstrate that none of the compounds is toxic to activated sludge, except ofloxacin to P. putida. The additives tested can be considered moderately toxic according to the more sensitive V. fischeri assays, whereas the EC50 values of the pharmaceuticals depend on the specific microorganism used in each test. Regarding the biodegradability, respirometric measurements were carried out for fast biodegradability assessment and the Zahn-Wellens test for inherent biodegradability. The evolution of the specific oxygen uptake rate (SOUR) showed that only diethyl phthalate was easily biodegradable and acetylsalicylic acid was partially biodegradable (98% and 65% degradation, respectively). The persistence of dichloromethane, ofloxacin and hidrochlorothiazide was confirmed along the 28 days of the Zahn-Wellens test whereas 1,1,1-trichloroethane showed inherent biodegradability (74% removal). Most of the chlorinated compounds, pharmaceuticals, bisphenol A and ethylenediaminetetraacetic acid were partially degraded in 28 d with total organic carbon (TOC) reduction ranging from 21% to 51%. Sulphamethoxazole showed certain biodegradation (50% removal) with TOC decrease around 31%, which indicates the formation of non-biodegradable by-productsThis work was financially supported by the Spanish Ministerio de Economía y Competitividad through the project CTM2013-43803-
A Glass Polyalkenoate Cement Carrier for Bone Morphogenetic Proteins
This work considers a glass polyalkenoate cement (GPC)-based carrier for the effective delivery of bone morphogenetic proteins (BMPs) at an implantation site. A 0.12 CaO–0.04 SrO–0.36 ZnO–0.48 SiO2 based glass and poly(acrylic acid) (PAA, Mw 213,000) were employed for the fabrication of the GPC. The media used for the water source in the GPC reaction was altered to produce a series of GPCs. The GPC liquid media was either 100 % distilled water with additions of albumin at 0, 2, 5 and 8 wt% of the glass content, 100 % formulation buffer (IFB), and 100 % BMP (150 µg rhBMP-2/ml IFB). Rheological properties, compressive strength, ion release profiles and BMP release were evaluated. Working times (Tw) of the formulated GPCs significantly increased with the addition of 2 % albumin and remained constant with further increases in albumin content or IFB solutions. Setting time (Ts) experienced an increase with 2 and 5 % albumin content, but a decrease with 8 % albumin. Changing the liquid source to IFB containing 5 % albumin had no significant effect on Ts compared to the 8 % albumin-containing BT101. Replacing the albumin with IFB/BMP-2 did not significantly affect Tw. However, Ts increased for the BT101_BMP-2 containing GPCs, compared to all other samples. The compressive strength evaluated 1 day post cement mixing was not affected significantly by the incorporation of BMPs, but the ion release did increase from the cements, particularly for Zn and Sr. The GPCs released BMP after the first day, which decreased in content during the following 6 days. This study has proven that BMPs can be immobilized into GPCs and may result in novel materials for clinical applications
Physical fitness and white matter microstructure in children with overweight or obesity: the ActiveBrains project
Recent studies investigated the association of cardiorespiratory fitness with white matter microstructure in children, yet little work has explored to what extent other components of physical fitness (i.e., muscular or motor fitness) are associated with white matter microstructure. Indeed, this association has not been previously explored in children with overweight/obesity who present a different white matter development. Therefore, we aimed to examine associations between physical fitness components and white matter microstructure in children with overweight/obesity. In total, 104 (10.04 +/- 1.15 years old; 43 girls) children were included in this cross-sectional study. Physical fitness was assessed using the ALPHA-fitness test battery. Fractional anisotropy (FA) and mean diffusivity were derived from diffusion tensor imaging (DTI). No association was found between physical fitness and global DTI metrics (all P>0.082). Within individual tracts, all associations became non-significant when analyses were adjusted for multiple comparisons. Using the voxel-wise approach, we identified a small cluster in the left lateral frontal lobe where children with greater upper-body muscular fitness showed higher FA (PFWE-corrected=0.042). Although our results cannot conclude physical fitness is related to white matter microstructure in children with overweight/obesity; those findings indicate that the association of muscular fitness with white matter microstructure might be more focal on frontal areas of the brain, as opposed to global differences
Preferred growth direction by PbS nanoplatelets preserves perovskite infrared light harvesting for stable, reproducible, and efficient solar cells
Formamidinium-based perovskite solar cells (PSCs) present the maximum theoretical efficiency of the lead perovskite family. However, formamidinium perovskite exhibits significant degradation in air. The surface chemistry of PbS has been used to improve the formamidinium black phase stability. Here, the use of PbS nanoplatelets with (100) preferential crystal orientation is reported, to potentiate the repercussion on the crystal growth of perovskite grains and to improve the stability of the material and consequently of the solar cells. As a result, a vertical growth of perovskite grains, a stable current density of 23 mA cm(-2), and a stable incident photon to current efficiency in the infrared region of the spectrum for 4 months is obtained, one of the best stability achievements for planar PSCs. Moreover, a better reproducibility than the control device, by optimizing the PbS concentration in the perovskite matrix, is achieved. These outcomes validate the synergistic use of PbS nanoplatelets to improve formamidinium long-term stability and performance reproducibility, and pave the way for using metastable perovskite active phases preserving their light harvesting capability
Proinflammatory diet is associated with increased risk of squamous cell head and neck cancer
Diets high in fruits and vegetables and low in red meat intake have been associated with decreased risk of head and neck cancer. Additionally, chronic inflammation pathways and their association with cancer have been widely described. We hypothesized a proinflammatory diet, as measured by the dietary inflammatory index (DII®), is associated with increased risk of head and neck cancer. We used the Carolina Head and Neck Cancer (CHANCE) study, a population-based case–control study of head and neck squamous cell carcinoma. Cases were recruited from a 46-county region in central North Carolina. Controls, frequency-matched on age, race, and sex were identified through the North Carolina Department of Motor Vehicle records. The DII score, adjusted for energy using the density approach (E-DII), was calculated from a food frequency questionnaire and split into four quartiles based on the distribution among controls. Adjusted odds ratios (ORs) were estimated with unconditional logistic regression. Cases had higher E-DII scores (i.e., a more proinflammatory diet) compared with controls (mean: −0.14 vs. −1.50; p value < 0.001). When compared with the lowest quartile, the OR for the highest quartile was 2.91 (95% confidence interval (CI): 2.16–3.95), followed by 1.93 (95% CI: 1.43–2.62) for the third quartile, and 1.37 (95% CI: 1.00–1.89) for the second quartile. Both alcohol and smoking had a significant additive interaction with E-DII (smoking relative excess risk due to interaction (RERI): 2.83; 95% CI: 1.36–4.30 and alcohol RERI: 1.75; 95% CI: 0.77–2.75). These results provide additional evidence for the association between proinflammatory diet and head and neck cancer
Effects of an exercise program on brain health outcomes for children with overweight or obesity
Importance Pediatric overweight and obesity are highly prevalent across the world, with implications for poorer cognitive and brain health. Exercise might potentially attenuate these adverse consequences.
Objectives To investigate the effects of an exercise program on brain health indicators, including intelligence, executive function, academic performance, and brain outcomes, among children with overweight or obesity and to explore potential mediators and moderators of the main effects of exercise.
Design, Setting, and Participants All preexercise and postexercise data for this 20-week randomized clinical trial of 109 children aged 8 to 11 years with overweight or obesity were collected from November 21, 2014, to June 30, 2016, with neuroimaging data processing and analyses conducted between June 1, 2017, and December 20, 2021. All 109 children were included in the intention-to-treat analyses; 90 children (82.6%) completed the postexercise evaluation and attended 70% or more of the recommended exercise sessions and were included in per-protocol analyses.
Interventions All participants received lifestyle recommendations. The control group continued their usual routines, whereas the exercise group attended a minimum of 3 supervised 90-minute sessions per week in an out-of-school setting.
Main Outcomes and Measures Intelligence, executive function (cognitive flexibility, inhibition, and working memory), and academic performance were assessed with standardized tests, and hippocampal volume was measured with magnetic resonance imaging.
Results The 109 participants included 45 girls (41.3%); participants had a mean (SD) body mass index of 26.8 (3.6) and a mean (SD) age of 10.0 (1.1) years at baseline. In per-protocol analyses, the exercise intervention improved crystallized intelligence, with the exercise group improving from before exercise to after exercise (mean z score, 0.62 [95% CI, 0.44-0.80]) compared with the control group (mean z score, –0.10 [95% CI, –0.28 to 0.09]; difference between groups, 0.72 SDs [95% CI, 0.46-0.97]; P < .001). Total intelligence also improved significantly more in the exercise group (mean z score, 0.69 [95% CI, 0.48-0.89]) than in the control group (mean z score, 0.07 [95% CI, –0.14 to 0.28]; difference between groups, 0.62 SDs [95% CI, 0.31-0.91]; P < .001). Exercise also positively affected a composite score of cognitive flexibility (mean z score: exercise group, 0.25 [95% CI, 0.05-0.44]; control group, –0.17 [95% CI, –0.39 to 0.04]; difference between groups, 0.42 SDs [95% CI, 0.13-0.71]; P = .005). These main effects were consistent in intention-to-treat analyses and after multiple-testing correction. There was a positive, small-magnitude effect of exercise on total academic performance (mean z score: exercise group, 0.31 [95% CI, 0.18-0.44]; control group, 0.10 [95% CI, –0.04 to 0.24]; difference between groups, 0.21 SDs [95% CI, 0.01-0.40]; P = .03), which was partially mediated by cognitive flexibility. Inhibition, working memory, hippocampal volume, and other brain magnetic resonance imaging outcomes studied were not affected by the exercise program. The intervention increased cardiorespiratory fitness performance as indicated by longer treadmill time to exhaustion (mean z score: exercise group, 0.54 [95% CI, 0.27-0.82]; control group, 0.13 [95% CI, –0.16 to 0.41]; difference between groups, 0.42 SDs [95% CI, 0.01-0.82]; P = .04), and these changes in fitness mediated some of the effects (small percentage of mediation [approximately 10%-20%]). The effects of exercise were overall consistent across the moderators tested, except for larger improvements in intelligence among boys compared with girls.
Conclusions and Relevance In this randomized clinical trial, exercise positively affected intelligence and cognitive flexibility during development among children with overweight or obesity. However, the structural and functional brain changes responsible for these improvements were not identified
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