863 resultados para morphologic behaviors


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Copyright © Taylor & Francis Group, LLC 2015.Type 2 diabetes is a major health burden in the United States, and population trends suggest this burden will increase. High interest in, and increased availability of, testing for genetic risk of type 2 diabetes presents a new opportunity for reducing type 2 diabetes risk for many patients; however, to date, there is little evidence that genetic testing positively affects type 2 diabetes prevention. Genetic information may not fit patients illness representations, which may reduce the chances of risk-reducing behavior changes. The present study aimed to examine illness representations in a clinical sample who are at risk for type 2 diabetes and interested in genetic testing. The authors used the Common Sense Model to analyze survey responses of 409 patients with type 2 diabetes risk factors. Patients were interested in genetic testing for type 2 diabetes risk and believed in its importance. Most patients believed that genetic factors are important to developing type 2 diabetes (67%), that diet and exercise are effective in preventing type 2 diabetes (95%), and that lifestyle changes are more effective than drugs (86%). Belief in genetic causality was not related to poorer self-reported health behaviors. These results suggest that patients interest in genetic testing for type 2 diabetes might produce a teachable moment that clinicians can use to counsel behavior change.

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Objective: The objective of this study was to explore the association between job strain and the co-occurrence of adverse health behaviors, smoking; heavy drinking; obesity, and physical inactivity. Methods. The authors studied cross-sectional data of 34,058 female and 8154 male public sector employees. Results: Multinomial logistic regression models adjusted for sex, age, basic education, marital status, and type of job contract showed that high job strain and passive jobs were associated with 1.3 to 1.4 times higher odds of having >= 3 (vs 0) adverse health behaviors. Among men, low job control was associated with a 1.3 fold likelihood and amon women active jobs were associated with a 1.2 fold likelihood of having >= 3 (vs 0) adverse behaviors. High demands were associated with a higher likelihood of co-occurrence of one to two (vs 0) adverse behav irs among women. Conclusions. b strain conditions may be associated with the co-occurrence of adverse health behaviors that contribute to preventable chronic diseases. Clinical Significance. Adversejob conditions may increase the likelihood of co-occurring health risk behaviors. Reducing work stress by increasingl ob control and decreasing psychologic demands might help efforts to promote healthy 1 festyles.

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To evaluate attentional and activity behaviors in 4-year-olds following prenatal selective serotonin reuptake inhibitor (SSRI) exposure.

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Internalizing behaviors in children between 4 and 5 years of age who had been prenatally exposed to psychotropic medications were investigated. The authors had previously reported the effects of prenatal medication exposure in this same cohort when they were newborns and infants at 3 and 8 months of age.

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The goal of the current study was to examine the moderating role of in-group social identity on relations between youth exposure to sectarian antisocial behavior in the community and aggressive behaviors. Participants included 770 mother-child dyads living in interfaced neighborhoods of Belfast. Youth answered questions about aggressive and delinquent behaviors as well as the extent to which they targeted their behaviors toward members of the other group. Structural equation modeling results show that youth exposure to sectarian antisocial behavior is linked with increases in both general and sectarian aggression and delinquency over one year. Reflecting the positive and negative effects of social identity, in-group social identity moderated this link, strengthening the relationship between exposure to sectarian antisocial behavior in the community and aggression and delinquency towards the out-group. However, social identity weakened the effect for exposure to sectarian antisocial behavior in the community on general aggressive behaviors. Gender differences also emerged; the relation between exposure to sectarian antisocial behavior and sectarian aggression was stronger for boys. The results have implications for understanding the complex role of social identity in intergroup relations for youth in post-accord societies.

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The application of the shape memory alloy NiTi in micro-electro-mechanical-systems (MEMSs) is extensive nowadays. In MEMS, complex while precise motion control is always vital. This makes the degradation of the functional properties of NiTi during cycling loading such as the appearance of residual strain become a serious problem to study, in particular for laser micro-welded NiTi in real applications. Although many experimental efforts have been put to study the mechanical properties of laser welded NiTi, surprisingly, up to the best of our understanding, there has not been attempts to quantitatively model the laser-welded NiTi under mechanical cycling in spite of the accurate prediction required in applications and the large number of constitutive models to quantify the thermo-mechanical behavior of shape memory alloys. As the first attempt to fill the gap, we employ a recent constitutive model, which describes the localized SIMT in NiTi under cyclic deformation; with suitable modifications to model the mechanical behavior of the laser welded NiTi under cyclic tension. The simulation of the model on a range of tensile cyclic deformation is consistent with the results of a series of experiments. From this, we conclude that the plastic deformation localized in the welded regions (WZ and HAZs) of the NiTi weldment can explain most of the extra amount of residual strain appearing in welded NiTi compared to the bare one. Meanwhile, contrary to common belief, we find that the ability of the weldment to memorize its transformation history, sometimes known as ‘return point memory’, still remains unchanged basically though the effective working limit of this ability reduces to within 6% deformation.

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This article discusses the effects of laser welding parameters such as power, welding speed, and focus position on the weld bead profile, microstructure, pseudo-elasticity (PE), and shape memory effect (SME) of NiTi foil with thickness of 250 um using 100W CW fiber laser. The parameter settings to produce the NiTi welds for analysis in this article were chosen from a fractional factorial design to ensure the welds produced were free of any apparent defect. The welds obtained were mainly of cellular dendrites with grain sizes ranging from 2.5 to 4.8 um at the weld centerline. A small amount of Ni3Ti was found in the welds. The onset of transformation temperatures (As and Ms) of the NiTi welds shifted to the negative side as compared to the as-received NiTi alloy. Ultimate tensile stress of the NiTi welds was comparable to the as received NiTi alloy, but a little reduction in the pseudo-elastic property was noted. Full penetration welds with desirable weld bead profiles and mechanical properties were successfully obtained in this study.

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Cell loss and regeneration were investigated and compared in the retinal microvasculature of age- and sex-matched normal and streptozotocin diabetic rats. Selective pericyte loss in the diabetic rat was characterized by changes in the pericyte to endothelial cell ratio in retinal capillaries isolated for microscopy by the trypsin digest technique. A comparison of 3- and 9-month-old normal rats showed no significant change in the pericyte to endothelial cell ratio (1:2.7). In diabetic animals the ratio was reduced to 1:4.03, which was statistically significant (P less than .001). Premitotic retinal vascular cells in normal and diabetic rats were labelled with tritiated thymidine and the labelling indices calculated from cell counts of trypsin digest preparations. Methyl H3 thymidine was infused continuously over an eight-day period using osmotic mini pumps. The labelling index of endothelial cells (0.33%) in normal rats increased to 0.91% in diabetic animals (P less than .05). The labelling index of pericyte cells in normal animals (0.16%) did not increase significantly (P greater than .05) in diabetic animals (0.19%). A special stain was used to exclude labelled polymorphonuclear leukocytes from the cell counts.

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We induced choroidal neovascularization in the rhesus monkey by impoverishing the blood supply to the inner retina and producing defects in Bruch's membrane by photocoagulation. Fourteen of 46 eyes undergoing photocoagulation developed neovascular fronds which were identified and categorized by histopathologic examination and fluorescein angiography. All new vessels gained access to the retina through defects in Bruch's membrane at the site of photocoagulation marks. In eight eyes the new vessels remained localized to the immediate vicinity of photocoagulation marks. In four eyes neovascular fronds infiltrated the subretinal space for distances up to 6 disk diameters from the point of entry into the retina. In the two eyes choroidovitreal neovascular complexes developed but rapidly regressed shortly after gaining the vitreous cavity. Fluorescein angiography demonstrated that all neovascular fronds were grossly incompetent to dye but that formed feeding channels had some degree of integrity. Light microscopic studies showed the proliferating networks to be composed of capillaries with well-formed basement membranes and more mature vessels with the basic structure of choroidal arteries and veins.

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The operant learning theory account of behaviors of clinical significance in people with intellectual disability (ID) has dominated the field for nearly 50 years. However, in the last two decades, there has been a substantial increase in published research that describes the behavioral phenotypes of genetic disorders and shows that behaviors such as self-injury and aggression are more common in some syndromes than might be expected given group characteristics. These cross-syndrome differences in prevalence warrant explanation, not least because this observation challenges an exclusively operant learning theory account. To explore this possible conflict between theoretical account and empirical observation, we describe the genetic cause and physical, social, cognitive and behavioral phenotypes of four disorders associated with ID (Angleman, Cornelia de Lange, Prader-Willi and Smith-Magenis syndromes) and focus on the behaviors of clinical significance in each syndrome. For each syndrome we then describe a model of the interactions between physical characteristics, cognitive and motivational endophenotypes and environmental factors (including operant reinforcement) to account for the resultant behavioral phenotype. In each syndrome it is possible to identify pathways from gene to physical phenotype to cognitive or motivational endophenotype to behavior to environment and back to behavior. We identify the implications of these models for responsive and early intervention and the challenges for research in this area. We identify a pressing need for meaningful dialog between different disciplines to construct better informed models that can incorporate all relevant and robust empirical evidence.

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The negative impact of political violence on adolescent adjustment is well established. Less is known about factors that affect adolescents' positive outcomes in ethnically divided societies, especially influences on prosocial behaviors toward the out-group, which may promote constructive relations. For example, understanding how inter-group experiences and attitudes motivate out-group helping may foster inter-group co-operation and help to consolidate peace. The current study investigated adolescents' overall and out-group prosocial behaviors across two time points in Belfast, Northern Ireland (N = 714 dyads; 49% male; Time 1: M = 14.7, SD = 2.0, years old). Controlling for Time 1 prosocial behaviors, age, and gender, multi-variate structural equation modeling showed that experience with inter-group sectarian threat predicted fewer out-group prosocial behaviors at Time 2 at the trend level. On the other hand, greater experience of intra-group non-sectarian threat at Time 1 predicted more overall and out-group prosocial behaviors at Time 2. Moreover, positive out-group attitudes strengthened the link between intra-group threat and out-group prosocial behaviors one year later. Finally, experience with intra-group non-sectarian threat and out-group prosocial behaviors at Time 1 was related to more positive out-group attitudes at Time 2. The implications for youth development and inter-group relations in post-accord societies are discussed.

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Bias-induced oxygen ion dynamics underpins a broad spectrum of electroresistive and memristive phenomena in oxide materials. Although widely studied by device-level and local voltage-current spectroscopies, the relationship between electroresistive phenomena, local electrochemical behaviors, and microstructures remains elusive. Here, the interplay between history-dependent electronic transport and electrochemical phenomena in a NiO single crystalline thin film with a number of well-defined defect types is explored on the nanometer scale using an atomic force microscopy-based technique. A variety of electrochemically-active regions were observed and spatially resolved relationship between the electronic and electrochemical phenomena was revealed. The regions with pronounced electroresistive activity were further correlated with defects identified by scanning transmission electron microscopy. Using fully coupled mechanical-electrochemical modeling, we illustrate that the spatial distribution of strain plays an important role in electrochemical and electroresistive phenomena. These studies illustrate an approach for simultaneous mapping of the electronic and ionic transport on a single defective structure level such as dislocations or interfaces, and pave the way for creating libraries of defect-specific electrochemical responses.

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In order to investigate the compatibility of candidate structural materials with liquid metals, two kinds of ferritic/martensitic steels were chosen to contact with lead–bismuth eutectic in sealed quartz–glass tubes. The corrosion exposures were for 500 and 3000 h. Results showed that the oxidation layer and carbide dissolution layer on the two steels grew with contact time under oxygen unsaturated condition. Short-term corrosion behavior of a newly developed steel showed better lead–bismuth eutectic corrosion resistance than T91 at 873 K.