965 resultados para Nonlattice self-similar fractal strings
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Little is known about the functional and neural architecture of social reasoning, one major obstacle being that we crucially lack the relevant tools to test potentially different social reasoning components. In the case of belief reasoning, previous studies tried to separate the processes involved in belief reasoning per se from those involved in the processing of the high incidental demands such as the working memory demands of typical belief tasks (e.g., Stone et al., 1998; Samson et al., 2004). In this study, we developed new belief tasks in order to disentangle, for the first time, two perspective taking components involved in belief reasoning: (1) the ability to inhibit one’s own perspective (self-perspective inhibition) and (2) the ability to infer someone else’s perspective as such (other-perspective taking). The two tasks had similar demands in other-perspective taking as they both required the participant to infer that a character has a false belief about an object’s location. However, the tasks varied in the self-perspective inhibition demands. In the task with the lowest self-perspective inhibition demands, at the time the participant had to infer the character’s false belief, he or she had no idea what the new object’s location was. In contrast, in the task with the highest self-perspective inhibition demands, at the time the participant had to infer the character’s false belief, he or she knew where the object was actually located (and this knowledge had thus to be inhibited). The two tasks were presented to a stroke patient, WBA, with right prefrontal and temporal damage. WBA performed well in the low-inhibition false belief task but showed striking difficulty in the task placing high self-perspective inhibition demands, showing a selective deficit in inhibiting self-perspective. WBA also made egocentric errors in other social and visual perspective taking tasks, indicating a difficulty with belief attribution extending to the attribution of emotions, desires and visual experiences to other people. The case of WBA, together with the recent report of three patients impaired in belief reasoning even when self-perspective inhibition demands were reduced (Samson et al., 2004), provide the first neuropsychological evidence that (a) the inhibition of one’s own point of view and (b) the ability to infer someone else’ s point of view, rely on distinct neural and functional processes.
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OBJECTIVES: Due to the high prevalence of renal failure in transcatheter aortic valve replacement (TAVR) candidates, a non-contrast MR technique is desirable for pre-procedural planning. We sought to evaluate the feasibility of a novel, non-contrast, free-breathing, self-navigated three-dimensional (SN3D) MR sequence for imaging the aorta from its root to the iliofemoral run-off in comparison to non-contrast two-dimensional-balanced steady-state free-precession (2D-bSSFP) imaging. METHODS: SN3D [field of view (FOV), 220-370 mm(3); slice thickness, 1.15 mm; repetition/echo time (TR/TE), 3.1/1.5 ms; and flip angle, 115°] and 2D-bSSFP acquisitions (FOV, 340 mm; slice thickness, 6 mm; TR/TE, 2.3/1.1 ms; flip angle, 77°) were performed in 10 healthy subjects (all male; mean age, 30.3 ± 4.3 yrs) using a 1.5-T MRI system. Aortic root measurements and qualitative image ratings (four-point Likert-scale) were compared. RESULTS: The mean effective aortic annulus diameter was similar for 2D-bSSFP and SN3D (26.7 ± 0.7 vs. 26.1 ± 0.9 mm, p = 0.23). The mean image quality of 2D-bSSFP (4; IQR 3-4) was rated slightly higher (p = 0.03) than SN3D (3; IQR 2-4). The mean total acquisition time for SN3D imaging was 12.8 ± 2.4 min. CONCLUSIONS: Our results suggest that a novel SN3D sequence allows rapid, free-breathing assessment of the aortic root and the aortoiliofemoral system without administration of contrast medium. KEY POINTS: • The prevalence of renal failure is high among TAVR candidates. • Non-contrast 3D MR angiography allows for TAVR procedure planning. • The self-navigated sequence provides a significantly reduced scanning time.
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Colloid self-assembly under external control is a new route to fabrication of advanced materials with novel microstructures and appealing functionalities. The kinetic processes of colloidal self-assembly have attracted great interests also because they are similar to many atomic level kinetic processes of materials. In the past decades, rapid technological progresses have been achieved on producing shape-anisotropic, patchy, core-shell structured particles and particles with electric/magnetic charges/dipoles, which greatly enriched the self-assembled structures. Multi-phase carrier liquids offer new route to controlling colloidal self-assembly. Therefore, heterogeneity is the essential characteristics of colloid system, while so far there still lacks a model that is able to efficiently incorporate these possible heterogeneities. This thesis is mainly devoted to development of a model and computational study on the complex colloid system through a diffuse-interface field approach (DIFA), recently developed by Wang et al. This meso-scale model is able to describe arbitrary particle shape and arbitrary charge/dipole distribution on the surface or body of particles. Within the framework of DIFA, a Gibbs-Duhem-type formula is introduced to treat Laplace pressure in multi-liquid-phase colloidal system and it obeys Young-Laplace equation. The model is thus capable to quantitatively study important capillarity related phenomena. Extensive computer simulations are performed to study the fundamental behavior of heterogeneous colloidal system. The role of Laplace pressure is revealed in determining the mechanical equilibrium of shape-anisotropic particles at fluid interfaces. In particular, it is found that the Laplace pressure plays a critical role in maintaining the stability of capillary bridges between close particles, which sheds light on a novel route to in situ firming compact but fragile colloidal microstructures via capillary bridges. Simulation results also show that competition between like-charge repulsion, dipole-dipole interaction and Brownian motion dictates the degree of aggregation of heterogeneously charged particles. Assembly and alignment of particles with magnetic dipoles under external field is studied. Finally, extended studies on the role of dipole-dipole interaction are performed for ferromagnetic and ferroelectric domain phenomena. The results reveal that the internal field generated by dipoles competes with external field to determine the dipole-domain evolution in ferroic materials.
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Background: Repeated self-harm represents the single strongest risk factor for suicide. To date no study with full national coverage has examined the pattern of hospital repeated presentations due to self-harm among young people. Methods: Data on consecutive self-harm presentations were obtained from the National Self-Harm Registry Ireland. Socio-demographic and behavioural characteristics of individuals aged 10–29 years who presented with self-harm to emergency departments in Ireland (2007–2014) were analysed. Risk of long-term repetition was assessed using survival analysis and time differences between the order of presentations using generalised estimating equation analysis. Results: The total sample comprised 28,700 individuals involving 42,642 presentations. Intentional drug overdose was the most prevalent method (57.9%). Repetition of self-harm occurred in 19.2% of individuals during the first year following a first presentation, of whom the majority (62.7%) engaged in one repeated act. Overall, the risk of repeated self-harm was similar between males and females. However, in the 20–24-year-old age group males were at higher risk than females. Those who used self-cutting were at higher risk for repetition than those who used intentional drug overdose, particularly among females. Age was associated with repetition only among females, in particular adolescents (15–19 years old) were at higher risk than young emerging adults (20–24 years old). Repeated self-harm risk increased significantly with the number of previous self-harm episodes. Time differences between first self-harm presentations were detected. Time between second and third presentation increased compared to time between first and second presentation among low frequency repeaters (patients with 3 presentations only within 1 year following a first presentation). The same time period decreased among high frequency repeaters (patients with at least 4 to more than 30 presentations). Conclusion: Young people with the highest risk for repeated self-harm were 15–19-year-old females and 20–24-year-old males. Self-cutting was the method associated with the highest risk of self-harm repetition. Time between first self-harm presentations represents an indicator of subsequent repetition. To prevent risk of repeated self-harm in young people, all individuals presenting at emergency departments due to self-harm should be provided with a risk assessment including psychosocial characteristics, history of self-harm and time between first presentations.
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A palavra monomania provém do grego monos que se traduz por "um" e mania que significa "mania". O emprego do termo em psiquiatria deve-se a Esquirol e mais tarde a Pierre Janet. Contudo, o uso da palavra não se circunscreve ao campo da psiquiatria, o conceito de monomania é também usado para definir as denominadas "manias do eu". Nos dias de hoje, a subjectividade, a particularidade de cada indivíduo apartou-se da noção de Homem como um todo objectivo. A massificação gerou a sociedade do narcisismo. A World Wide Web permitiu ao sujeito dar a conhecer ao mundo a sua individualidade. O sujeito é livre de se mostrar, de se fazer ouvir, de contar as suas histórias e principalmente a sua própria. À semelhança do nosso quotidiano, podemos encontrar na arte contemporânea propostas artísticas que se prendem com o conceito de monomania, como o exemplo das mitologias individuais, auto-narrativas e auto-ficções de Sophie Calle: "de vivre sa vie pour faire ceuvre et de faire ceuvre pour vivre sa vie." ABSTRACT: Etymologically, "monomania" originates from the Greek words "monos" and "mania". The former refers to the notion of "one" and the latter to "mania". The term's introduction in the field of psychiatry is attributed first to Esquirol and later Pierre Janet. Usage of the word isn’t, however, exclusive to psychiatric jargon: the concept of monomania is also used to define so called "manias of the self’. Today, the subjectivity and specificity of each individual have distanced themselves from the notion of Man as an objective whole. Massification has led to a society of narcissism. The World Wide Web has allowed the subject to make her individuality known to the world at large. The subject is free to exhibit herself, make herself heard, tell her stories, and especially her own. ln a way similar to daily life, we find agendas in contemporary art that approach the concept of monomania, such as the personal mythologies, self-narratives and selffictions of Sophie Calle: "de vivre sa vie pour faire oeuvre et de faire oeuvre pour vivre sa vie."
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Objectives: To adapt for the Portuguese language the Self-Care of Heart Failure Index V6.2, analyse the self-care in maintenance, management skills and self-confidence of patients with heart failure who attend the nursing consultation of two Hospitals. Method: Explo- ratory study, sample 110 patients who frequented the nursing consultation for patients with heart failure of two Portuguese hospitals, conducted in the period of 6 months. He appea- led to the descriptive statistics and psychometric tests. Results: Internal consistency similar to the original scale. Mostly elderly, low literacy patients in self-care, low values associated with physical activity to the control of salt in meals taken away from home and inadequate control of signs and symptoms. Conclusion: Patients’ present difficulties in maintenance and management of the disease are self-confident face anyway. This instrument allows for individualized assessment leading to decision-making and action adjusted.
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The cerebral cortex presents self-similarity in a proper interval of spatial scales, a property typical of natural objects exhibiting fractal geometry. Its complexity therefore can be characterized by the value of its fractal dimension (FD). In the computation of this metric, it has usually been employed a frequentist approach to probability, with point estimator methods yielding only the optimal values of the FD. In our study, we aimed at retrieving a more complete evaluation of the FD by utilizing a Bayesian model for the linear regression analysis of the box-counting algorithm. We used T1-weighted MRI data of 86 healthy subjects (age 44.2 ± 17.1 years, mean ± standard deviation, 48% males) in order to gain insights into the confidence of our measure and investigate the relationship between mean Bayesian FD and age. Our approach yielded a stronger and significant (P < .001) correlation between mean Bayesian FD and age as compared to the previous implementation. Thus, our results make us suppose that the Bayesian FD is a more truthful estimation for the fractal dimension of the cerebral cortex compared to the frequentist FD.
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The aim of the study was to analyze the frequency of epidermal growth factor receptor (EGFR) mutations in Brazilian non-small cell lung cancer patients and to correlate these mutations with response to benefit of platinum-based chemotherapy in non-small cell lung cancer (NSCLC). Our cohort consisted of prospective patients with NSCLCs who received chemotherapy (platinum derivates plus paclitaxel) at the [UNICAMP], Brazil. EGFR exons 18-21 were analyzed in tumor-derived DNA. Fifty patients were included in the study (25 with adenocarcinoma). EGFR mutations were identified in 6/50 (12 %) NSCLCs and in 6/25 (24 %) adenocarcinomas; representing the frequency of EGFR mutations in a mostly self-reported White (82.0 %) southeastern Brazilian population of NSCLCs. Patients with NSCLCs harboring EGFR exon 19 deletions or the exon 21 L858R mutation were found to have a higher chance of response to platinum-paclitaxel (OR 9.67 [95 % CI 1.03-90.41], p = 0.047). We report the frequency of EGFR activating mutations in a typical southeastern Brazilian population with NSCLC, which are similar to that of other countries with Western European ethnicity. EGFR mutations seem to be predictive of a response to platinum-paclitaxel, and additional studies are needed to confirm or refute this relationship.
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The development and maintenance of the sealing of the root canal system is the key to the success of root canal treatment. The resin-based adhesive material has the potential to reduce the microleakage of the root canal because of its adhesive properties and penetration into dentinal walls. Moreover, the irrigation protocols may have an influence on the adhesiveness of resin-based sealers to root dentin. The objective of the present study was to evaluate the effect of different irrigant protocols on coronal bacterial microleakage of gutta-percha/AH Plus and Resilon/Real Seal Self-etch systems. One hundred ninety pre-molars were used. The teeth were divided into 18 experimental groups according to the irrigation protocols and filling materials used. The protocols used were: distilled water; sodium hypochlorite (NaOCl)+eDTA; NaOCl+H3PO4; NaOCl+eDTA+chlorhexidine (CHX); NaOCl+H3PO4+CHX; CHX+eDTA; CHX+ H3PO4; CHX+eDTA+CHX and CHX+H3PO4+CHX. Gutta-percha/AH Plus or Resilon/Real Seal Se were used as root-filling materials. The coronal microleakage was evaluated for 90 days against Enterococcus faecalis. Data were statistically analyzed using Kaplan-Meier survival test, Kruskal-Wallis and Mann-Whitney tests. No significant difference was verified in the groups using chlorhexidine or sodium hypochlorite during the chemo-mechanical preparation followed by eDTA or phosphoric acid for smear layer removal. The same results were found for filling materials. However, the statistical analyses revealed that a final flush with 2% chlorhexidine reduced significantly the coronal microleakage. A final flush with 2% chlorhexidine after smear layer removal reduces coronal microleakage of teeth filled with gutta-percha/AH Plus or Resilon/Real Seal SE.
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this study aimed to investigate the cognitive and behavioral profiles, as well as the psychiatric symptoms and disorders in children with three different genetic syndromes with similar sociocultural and socioeconomic backgrounds. thirty-four children aged 6 to 16 years, with Williams-Beuren syndrome (n=10), Prader-Willi syndrome (n=11), and Fragile X syndrome (n=13) from the outpatient clinics of Child Psychiatry and Medical Genetics Department were cognitively assessed through the Wechsler Intelligence Scale for Children (WISC-III). Afterwards, a full-scale intelligence quotient (IQ), verbal IQ, performance IQ, standard subtest scores, as well as frequency of psychiatric symptoms and disorders were compared among the three syndromes. significant differences were found among the syndromes concerning verbal IQ and verbal and performance subtests. Post-hoc analysis demonstrated that vocabulary and comprehension subtest scores were significantly higher in Williams-Beuren syndrome in comparison with Prader-Willi and Fragile X syndromes, and block design and object assembly scores were significantly higher in Prader-Willi syndrome compared with Williams-Beuren and Fragile X syndromes. Additionally, there were significant differences between the syndromes concerning behavioral features and psychiatric symptoms. The Prader-Willi syndrome group presented a higher frequency of hyperphagia and self-injurious behaviors. The Fragile X syndrome group showed a higher frequency of social interaction deficits; such difference nearly reached statistical significance. the three genetic syndromes exhibited distinctive cognitive, behavioral, and psychiatric patterns.
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Low-density nanostructured foams are often limited in applications due to their low mechanical and thermal stabilities. Here we report an approach of building the structural units of three-dimensional (3D) foams using hybrid two-dimensional (2D) atomic layers made of stacked graphene oxide layers reinforced with conformal hexagonal boron nitride (h-BN) platelets. The ultra-low density (1/400 times density of graphite) 3D porous structures are scalably synthesized using solution processing method. A layered 3D foam structure forms due to presence of h-BN and significant improvements in the mechanical properties are observed for the hybrid foam structures, over a range of temperatures, compared with pristine graphene oxide or reduced graphene oxide foams. It is found that domains of h-BN layers on the graphene oxide framework help to reinforce the 2D structural units, providing the observed improvement in mechanical integrity of the 3D foam structure.
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The article seeks to investigate patterns of performance and relationships between grip strength, gait speed and self-rated health, and investigate the relationships between them, considering the variables of gender, age and family income. This was conducted in a probabilistic sample of community-dwelling elderly aged 65 and over, members of a population study on frailty. A total of 689 elderly people without cognitive deficit suggestive of dementia underwent tests of gait speed and grip strength. Comparisons between groups were based on low, medium and high speed and strength. Self-related health was assessed using a 5-point scale. The males and the younger elderly individuals scored significantly higher on grip strength and gait speed than the female and oldest did; the richest scored higher than the poorest on grip strength and gait speed; females and men aged over 80 had weaker grip strength and lower gait speed; slow gait speed and low income arose as risk factors for a worse health evaluation. Lower muscular strength affects the self-rated assessment of health because it results in a reduction in functional capacity, especially in the presence of poverty and a lack of compensatory factors.
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This article seeks to investigate associations between satisfaction with life and sociodemographic variables, health conditions, functionality, social involvement and social support among elderly caregivers and non-caregivers, as well as between satisfaction and the intensity of stress in the caregiver group. A sample of 338 caregivers was selected according to two items of the Brazilian version of the Elders Life Stress Inventory. A comparison-group of elderly non-caregivers was selected at random, with a similar gender, age and income profile. Data were derived from self-reported questionnaires and scales. Elderly caregivers with low levels of satisfaction and high levels of stress revealed more symptoms of insomnia, fatigue, diseases and worse IADL performance. Those with greater satisfaction and less stress revealed a good level of social support. Insomnia, depression and fatigue were associated with low satisfaction among caregivers, and with fatigue, depression and low social support among non-caregivers. It was considered relevant that instrumental, psychological and informative support can improve the quality of life and the quality of care provided by elderly caregivers, especially if they are affected by unfavorable health and psychosocial conditions and low satisfaction with life.
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The objective of this study was to analyze the prevalence of diabetes in older people and the adopted control measures. Data regarding older diabetic individuals who participated in the Health Surveys conducted in the Municipality of Sao Paulo, SP, ISA-Capital, in 2003 and 2008, which were cross-sectional studies, were analyzed. Prevalences and confidence intervals were compared between 2003 and 2008, according to sociodemographic variables. The combination of the databases was performed when the confidence intervals overlapped. The Chi-square (level of significance of 5%) and the Pearson's Chi-square (Rao-Scott) tests were performed. The variables without overlap between the confidence intervals were not tested. The age of the older adults was 60-69 years. The majority were women, Caucasian, with an income of between > 0.5 and 2.5 times the minimum salary and low levels of schooling. The prevalence of diabetes was 17.6% (95%CI 14.9;20.6) in 2003 and 20.1% (95%CI 17.3;23.1) in 2008, which indicates a growth over this period (p at the limit of significance). The most prevalent measure adopted by the older adults to control diabetes was hypoglycemic agents, followed by diet. Physical activity was not frequent, despite the significant differences observed between 2003 and 2008 results. The use of public health services to control diabetes was significantly higher in older individuals with lower income and lower levels of education. Diabetes is a complex and challenging disease for patients and the health systems. Measures that encourage health promotion practices are necessary because they presented a smaller proportion than the use of hypoglycemic agents. Public health policies should be implemented, and aimed mainly at older individuals with low income and schooling levels. These changes are essential to improve the health condition of older diabetic patients.
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Chronic and systemic treatment of rodents with rotenone, a classical inhibitor of mitochondrial respiratory complex I, results in neurochemical, behavioral, and neuropathological features of Parkinson's disease. The aim of the present study was to evaluate whether brain mitochondria from old rats (24 months old) would be more susceptible to rotenone-induced inhibition of oxygen consumption and increased generation of H2O2 than mitochondria from young-adult rats (3-4 months old). Isolated brain mitochondria were incubated in the presence of different rotenone concentrations (5, 10, and 100nM), and oxygen consumption and H2O2 production were measured during respiratory states 3 (ADP-stimulated respiration) and 4 (resting respiration). Respiratory state 3 and citrate synthase activity were significantly lower in mitochondria from old rats. Mitochondria from young-adult and old rats showed similar sensitivity to rotenone-induced inhibition of oxygen consumption. Similarly, H2O2 production rates by both types of mitochondria were dose-dependently stimulated to the same extent by increasing concentrations of rotenone. We conclude that rotenone exerts similar effects on oxygen consumption and H2O2 production by isolated brain mitochondria from young-adult and old rats. Therefore, aging does not increase the mitochondrial H2O2 generation in response to complex I inhibition.