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Ferroelectrics have recently attracted attention as a candidate class of materials for use in photovoltaic devices, and for the coupling of light absorption with other functional properties. In these materials, the strong inversion symmetry breaking that is due to spontaneous electric polarization promotes the desirable separation of photo-excited carriers and allows voltages higher than the bandgap, which may enable efficiencies beyond the maximum possible in a conventional p-n junction solar cell. Ferroelectric oxides are also stable in a wide range of mechanical, chemical and thermal conditions and can be fabricated using low-cost methods such as sol-gel thin-film deposition and sputtering. Recent work has shown how a decrease in ferroelectric layer thickness and judicious engineering of domain structures and ferroelectric-electrode interfaces can greatly increase the current harvested from ferroelectric absorber materials, increasing the power conversion efficiency from about 10(-4) to about 0.5 per cent. Further improvements in photovoltaic efficiency have been inhibited by the wide bandgaps (2.7-4 electronvolts) of ferroelectric oxides, which allow the use of only 8-20 per cent of the solar spectrum. Here we describe a family of single-phase solid oxide solutions made from low-cost and non-toxic elements using conventional solid-state methods: [KNbO3]1 - x[BaNi1/2Nb1/2O3 - δ]x (KBNNO). These oxides exhibit both ferroelectricity and a wide variation of direct bandgaps in the range 1.1-3.8 electronvolts. In particular, the x = 0.1 composition is polar at room temperature, has a direct bandgap of 1.39 electronvolts and has a photocurrent density approximately 50 times larger than that of the classic ferroelectric (Pb,La)(Zr,Ti)O3 material. The ability of KBNNO to absorb three to six times more solar energy than the current ferroelectric materials suggests a route to viable ferroelectric semiconductor-based cells for solar energy conversion and other applications.
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OBJECTIVE: Recently, Christianson syndrome (CS) has been determined to be caused by mutations in the X-linked Na(+) /H(+) exchanger 6 (NHE6). We aimed to determine the diagnostic criteria and mutational spectrum for CS. METHODS: Twelve independent pedigrees (14 boys, age = 4-19 years) with mutations in NHE6 were administered standardized research assessments, and mutations were characterized. RESULTS: The mutational spectrum was composed of 9 single nucleotide variants, 2 indels, and 1 copy number variation deletion. All mutations were protein-truncating or splicing mutations. We identified 2 recurrent mutations (c.1498 c>t, p.R500X; and c.1710 g>a, p.W570X). Otherwise, all mutations were unique. In our study, 7 of 12 mutations (58%) were de novo, in contrast to prior literature wherein mutations were largely inherited. We also report prominent neurological, medical, and behavioral symptoms. All CS participants were nonverbal and had intellectual disability, epilepsy, and ataxia. Many had prior diagnoses of autism and/or Angelman syndrome. Other neurologic symptoms included eye movement abnormalities (79%), postnatal microcephaly (92%), and magnetic resonance imaging evidence of cerebellar atrophy (33%). Regression was noted in 50%, with recurrent presentations involving loss of words and/or the ability to walk. Medical symptoms, particularly gastrointestinal symptoms, were common. Height and body mass index measures were below normal ranges in most participants. Behavioral symptoms included hyperkinetic behavior (100%), and a majority exhibited high pain threshold. INTERPRETATION: This is the largest cohort of independent CS pedigrees reported. We propose diagnostic criteria for CS. CS represents a novel neurogenetic disorder with general relevance to autism, intellectual disability, Angelman syndrome, epilepsy, and regression.
Assuntos
Ataxia/complicações , Ataxia/genética , Deficiências do Desenvolvimento/genética , Epilepsia/complicações , Epilepsia/genética , Doenças Genéticas Ligadas ao Cromossomo X/complicações , Doenças Genéticas Ligadas ao Cromossomo X/genética , Deficiência Intelectual/complicações , Deficiência Intelectual/genética , Microcefalia/complicações , Microcefalia/genética , Mutação/genética , Transtornos da Motilidade Ocular/complicações , Transtornos da Motilidade Ocular/genética , Trocadores de Sódio-Hidrogênio/genética , Adolescente , Ataxia/patologia , Transtorno Autístico/etiologia , Transtorno Autístico/genética , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Criança , Pré-Escolar , Deficiências do Desenvolvimento/complicações , Deficiências do Desenvolvimento/patologia , Progressão da Doença , Eletroencefalografia , Epilepsia/etiologia , Epilepsia/patologia , Feminino , Doenças Genéticas Ligadas ao Cromossomo X/patologia , Genótipo , Humanos , Deficiência Intelectual/patologia , Imageamento por Ressonância Magnética , Masculino , Microcefalia/patologia , Transtornos da Motilidade Ocular/patologia , Fenótipo , Análise de Regressão , Adulto JovemRESUMO
This study examined whether elevations on four variables (drive for thinness, depressed mood, maladaptive cognitions, and ineffectiveness) were related to increased severity of eating disorder symptoms over a 4-year prospective interval in a sample of female undergraduates (N=80). Results indicated that initial scores on the four variables were related to severity of anorexic and bulimic symptoms 4 years later. Examination of each variable individually indicated that anorexia and bulimia may have different risk pathways, and that initial maladaptive cognitions and drive for thinness scores were more related to later eating disorder symptoms than were depressed mood or ineffectiveness.
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Christianson syndrome (CS) is an X-linked neurodevelopmental disorder caused by deleterious mutations in SLC9A6. Affected families organized the inaugural Christianson Syndrome Association conference to advance CS knowledge and develop questions that may be prioritized in future research.
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This meta-analysis summarizes 41 studies that examined associations between characteristics of adolescent participants in juvenile drug treatment court and outcomes (i.e., premature termination, recidivism). A summary of within- and post-program recidivism rates was calculated, as was a global estimate of the premature drop-out rate. One clear trend in the available studies was the dramatic difference in recidivism rates for adolescents who succeed in graduating from drug court, relative to those who do not. In addition, the review revealed that behavior patterns evidenced during drug court participation were most strongly associated with both the probability of graduating successfully from drug court and recidivism (e.g., few in-program arrests, citations, detentions, and referrals; greater length of time in program or amount of treatment; lower use of drug and alcohol use, few positive urine screens, greater school attendance). Unfortunately, non-white participants tend to have a lower probability of graduation from drug court and experience higher recidivism during and following the program. Available juvenile drug treatment court studies confirm a number of reputed adolescent risk factors associated with substance abuse, criminality, treatment failure, and recidivism among adolescents (e.g., higher levels of emotional and behavioral problems, higher levels and severity of pre-program substance abuse, male gender). Suggestions for improving the effects of juvenile drug treatment court based on key results of the meta-analysis are offered.
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Crime/estatística & dados numéricos , Delinquência Juvenil/reabilitação , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Adolescente , Consumo de Bebidas Alcoólicas/epidemiologia , Feminino , Humanos , Masculino , Fatores de Risco , Fatores Sexuais , Falha de Tratamento , Resultado do TratamentoRESUMO
BACKGROUND CONTEXT: Elective lumbar discectomy among injured workers is a prevalent spine surgery that often requires a lengthy rehabilitation. It is important to determine presurgical biopsychosocial predictors of compensation and medical costs in such patients. PURPOSE: To determine if presurgical biopsychosocial variables are predictive of compensation and medical costs in a cohort of Utah patients who have undergone open or microlumbar discectomy that are receiving workers' compensation. STUDY DESIGN/SETTING: A retrospective cohort study consisting of a review of presurgical medical records and accrued medical and compensation costs. PATIENT SAMPLE: A consecutive sample of 266 compensated workers from Utah who had undergone either open discectomy or microlumbar discectomy from 1994 to 2000. All patients were at least 2 years postsurgery at the time of follow-up. OUTCOME MEASURES: Total accrued medical, compensation, and aggregate costs. METHODS: A retrospective review of presurgical biopsychosocial variables and total accrued medical, compensation, and aggregate costs. RESULTS: Presurgical variables were statistically significantly correlated with medical and compensation costs. Multiple linear regression models accounted for 31% of variation in compensation costs, 32% in medical costs, and 43% in total aggregate costs. CONCLUSIONS: Presurgical biopsychosocial variables are important predictors of compensated lumbar discectomy costs. Medical cost control programs might benefit from identifying biopsychosocial variables related to increased costs.
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Discotomia/economia , Custos de Cuidados de Saúde , Dor Lombar/cirurgia , Vértebras Lombares/cirurgia , Indenização aos Trabalhadores , Adulto , Consumo de Bebidas Alcoólicas , Avaliação da Deficiência , Discotomia/psicologia , Discotomia/reabilitação , Feminino , Humanos , Dor Lombar/psicologia , Dor Lombar/reabilitação , Masculino , Valor Preditivo dos Testes , Cuidados Pré-Operatórios , Estudos Retrospectivos , Meio Social , UtahRESUMO
OBJECTIVE: To examine, in an exploratory analysis, the association between vascular conditions and the occurrence of neuropsychiatric symptoms (NPS) in a population-based sample of incident Alzheimer's disease (AD). METHODS: The sample consisted of 254 participants, identified through two waves of assessment. NPS were assessed using the Neuropsychiatric Inventory. Prior to the onset of AD, data regarding a history of stroke, hypertension, hyperlipidemia, heart attack or coronary artery bypass graft (CABG), and diabetes were recorded. Logistic regression procedures were used to examine the relationship of each vascular condition to individual neuropsychiatric symptoms. Covariates considered were age, gender, education, APOE genotype, dementia severity, and overall health status. RESULTS: One or more NPS were observed in 51% of participants. Depression was most common (25.8%), followed by apathy (18.6%), and irritability (17.7%). Least common were elation (0.8%), hallucinations (5.6%), and disinhibition (6.0%). Stroke prior to the onset of AD was associated with increased risk of delusions (OR = 4.76, p = 0.02), depression (OR = 3.87, p = 0.03), and apathy (OR = 4.48, p = 0.02). Hypertension was associated with increased risk of delusions (OR = 2.34, p = 0.02), anxiety (OR = 4.10, p = 0.002), and agitation/aggression (OR = 2.82, p = 0.01). No associations were observed between NPS and diabetes, hyperlipidemia, heart attack or CABG, or overall health. CONCLUSIONS: Results suggest that a history of stroke and hypertension increase the risk of specific NPS in patients with AD. These conditions may disrupt neural circuitry in brain areas involved in NPS. Findings may provide an avenue for reduction in occurrence of NPS through the treatment or prevention of vascular risk conditions.
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Doença de Alzheimer/epidemiologia , Doença de Alzheimer/fisiopatologia , Encéfalo/fisiopatologia , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/fisiopatologia , Agitação Psicomotora/epidemiologia , Agitação Psicomotora/fisiopatologia , Acidente Vascular Cerebral/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Doença de Alzheimer/diagnóstico , Área Programática de Saúde , Ponte de Artéria Coronária/estatística & dados numéricos , Feminino , Genótipo , Humanos , Hiperlipidemias/epidemiologia , Masculino , Infarto do Miocárdio/cirurgia , Prevalência , Fatores de Risco , Índice de Gravidade de Doença , Acidente Vascular Cerebral/fisiopatologia , Estados Unidos/epidemiologiaRESUMO
The purpose of this study was to experimentally examine the effects of exposure to the thin-ideal body image on women's affect, self-esteem, body satisfaction, eating disorder symptoms, and level of internalization of the thin-ideal. College women (N=145) were randomly exposed to photographs from popular magazines containing either thin-ideal images or neutral images. Exposure to thin-ideal magazine images increased body dissatisfaction, negative mood states, and eating disorder symptoms and decreased self-esteem, although it did not cause more internalization of the thin-ideal. Exposure to thin-ideal media images may contribute to the development of eating disorders by causing body dissatisfaction, negative moods, low self-esteem, and eating disorders symptoms among women.