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1.
Nat Commun ; 14(1): 5812, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37726328

RESUMO

Magnetic topological semimetals allow for an effective control of the topological electronic states by tuning the spin configuration. Among them, Weyl nodal line semimetals are thought to have the greatest tunability, yet they are the least studied experimentally due to the scarcity of material candidates. Here, using a combination of angle-resolved photoemission spectroscopy and quantum oscillation measurements, together with density functional theory calculations, we identify the square-net compound EuGa4 as a magnetic Weyl nodal ring semimetal, in which the line nodes form closed rings near the Fermi level. The Weyl nodal ring states show distinct Landau quantization with clear spin splitting upon application of a magnetic field. At 2 K in a field of 14 T, the transverse magnetoresistance of EuGa4 exceeds 200,000%, which is more than two orders of magnitude larger than that of other known magnetic topological semimetals. Our theoretical model suggests that the non-saturating magnetoresistance up to 40 T arises as a consequence of the nodal ring state.

2.
Graefes Arch Clin Exp Ophthalmol ; 259(6): 1555-1567, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33791845

RESUMO

PURPOSE: To determine the long-term incidence of pseudophakic retinal detachment (PRD) after phacoemulsification and the weight of the main risk factors in the appearance of such complication in a large sample. To implement a customized formula and a software calculation program able to quantify the risk of suffering PRD applicable to all lens extraction patients. METHODS: Retrospective cumulative risk analysis conducted on 178,515 eyes operated under similar conditions in a group of refractive surgery clinics (Clínica Baviera SL) located in a relatively limited geographical area (Spain). A survival analysis was performed and the data were modelled using the Weibull regression to determine the risk over a period of 16 years and to estimate the association of different risk factors: sex, age, axial length (AXL) of the eye, intraoperative posterior capsule rents (PCR), and YAG laser capsulotomies. The resulting estimates were translated into a predictive equation for hazard rates and survival probabilities. Later, an application was developed to make prediction available for the clinical community in order to estimate the potential risk of any hypothetical case before lens surgery. RESULTS: Globally, 1521 (0.85%) cases of PRD were diagnosed during the period. The risk for PRD was significantly greater in males (5.48 [2.94-10.2]; p < 0.001), in long eyes (1.24 [1.21-1.26]; p < 0.001), and also after posterior capsule rents (13.97 [11.61-16.82]; p < 0.001). Posterior capsule rupture increased the risk of PRD up to fourteen times. CONCLUSIONS: From weaker to stronger impact, age, axial length, sex, and intraoperative posterior capsule rent were significant risk factors for the appearance of PRD after lens extraction.


Assuntos
Extração de Catarata , Facoemulsificação , Descolamento Retiniano , Seguimentos , Humanos , Masculino , Facoemulsificação/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/epidemiologia , Descolamento Retiniano/etiologia , Estudos Retrospectivos , Fatores de Risco
3.
Neuropsychologia ; 131: 1-8, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31145908

RESUMO

Studies of set-shifting in adolescent AN present conflicting results, since not all have found differences with regard to controls. To date, no functional Magnetic Resonance Imaging (fMRI) studies have been carried out in adolescent patients, nor have patients been assessed after weight recovery. In this study, 30 female AN patients aged 12-17 and 16 matched control subjects were assessed both at baseline and after six months and renutrition using a structured diagnostic interview, clinical and neurocognitive scales, and fMRI during a set-shifting task. Adolescent AN patients presented similar performance on different neurocognitive tests and also on a set-shifting task during fMRI, but they showed a lower activation in the inferior and middle occipital and lingual gyri, fusiform gyri and cerebellum during the set-shifting task. No correlations were found between decreased activation and clinical variables such as body mass index, eating or depressive symptoms. After six months of treatment and renutrition in AN patients, there were no differences between patients and controls. These results show that adolescent AN patients have lower activation in relevant brain areas during a set-shifting task, and support the use of fMRI with set-shifting paradigms as a biomarker in future studies.


Assuntos
Anorexia Nervosa/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Enquadramento Psicológico , Adolescente , Anorexia Nervosa/psicologia , Criança , Cognição/fisiologia , Estudos Transversais , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Testes Neuropsicológicos
4.
Ultramicroscopy ; 186: 23-29, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29247969

RESUMO

The delocalization of x-ray signals limits the spatial resolution in atomic-scale elemental mapping by scanning transmission electron microscopy (STEM) using energy-dispersive x-ray spectroscopy (EDS). In this study, using a SrTiO3 [001] single crystal, we show that the x-ray localization to atomic columns is strongly dependent on crystal thickness, and a thin crystal is critical for improving the spatial resolution in atomic-scale EDS mapping. A single-frame scanning technique is used in this study instead of the multiple-frame technique to avoid peak broadening due to tracking error. The strong thickness dependence is realized by measuring the full width at half maxima (FWHM) as well as the peak-to-valley (P/V) ratio of the EDS profiles for Ti K and Sr K + L, obtained at several crystal thicknesses. A FWHM of about 0.16 nm and a P/V ratio of greater than 7.0 are obtained for Ti K for a crystal thickness of less than 20 nm. With increasing crystal thickness, the FWHM and P/V ratio increases and decreases, respectively, indicating the advantage of using a thin crystal for high-resolution EDS mapping.

5.
Dev Cogn Neurosci ; 17: 35-44, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26657414

RESUMO

There is limited evidence on the effects of age and sex on intrinsic connectivity of networks underlying cognition during childhood and adolescence. Independent component analysis was conducted in 113 subjects aged 7-18; the default mode, executive control, anterior salience, basal ganglia, language and visuospatial networks were identified. The effect of age was examined with multiple regression, while sex and 'age × sex' interactions were assessed by dividing the sample according to age (7-12 and 13-18 years). As age increased, connectivity in the dorsal and ventral default mode network became more anterior and posterior, respectively, while in the executive control network, connectivity increased within frontoparietal regions. The basal ganglia network showed increased engagement of striatum, thalami and precuneus. The anterior salience network showed greater connectivity in frontal areas and anterior cingulate, and less connectivity of orbitofrontal, middle cingulate and temporoparietal regions. The language network presented increased connectivity of inferior frontal and decreased connectivity within the right middle frontal and left inferior parietal cortices. The visuospatial network showed greater engagement of inferior parietal and frontal cortices. No effect of sex, nor age by sex interactions was observed. These findings provide evidence of strengthening of cortico-cortical and cortico-subcortical networks across childhood and adolescence.


Assuntos
Mapeamento Encefálico , Lobo Frontal/fisiologia , Rede Nervosa/fisiologia , Lobo Parietal/fisiologia , Adolescente , Fatores Etários , Gânglios da Base/fisiologia , Mapeamento Encefálico/métodos , Criança , Feminino , Giro do Cíngulo/fisiologia , Humanos , Idioma , Masculino , Fatores Sexuais , Tálamo/fisiologia
6.
J Atten Disord ; 18(1): 52-60, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22441888

RESUMO

OBJECTIVE: The purpose of this study was to examine whether persisting hyperactivity into adulthood was associated with impaired family, friendship, and partner relationships or poor coping skills in everyday life. METHOD: A 20-year community-based follow-up of 6- to 7-year-old boys showing pervasive hyperactivity (n = 40) and unaffected controls (n = 25) was conducted. At age 27 years, participants were assessed with detailed interview techniques as well as self-report ratings. RESULTS: ADHD in adulthood was associated with problems in intimate relationships and negotiation skills. Antisocial behavior did not influence the association, but remitting childhood hyperactivity was not associated with social relationship difficulties in adulthood. CONCLUSION: In an untreated, community-based sample of hyperactive children, the risk for unsatisfactory social relationships is largely confined to those patients who still show ADHD in adulthood. The majority of patients who experience childhood hyperactivity have positive social relationships in adulthood.


Assuntos
Adaptação Psicológica , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Relações Familiares , Amigos , Relações Interpessoais , Adulto , Estudos de Casos e Controles , Criança , Doença Crônica , Feminino , Seguimentos , Humanos , Masculino , Negociação , Pesquisa Qualitativa , Autorrelato
7.
J Biotechnol ; 160(3-4): 176-88, 2012 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-22475573

RESUMO

A mathematical model was developed for a compact anoxic-anaerobic-aerobic filter reactor with liquid recirculation for the treatment of fishing effluents. The model includes denitrification, anaerobic digestion, aerobic carbon oxidation and nitrification steps, as well as an evaluation of the liquid gas mass transfer and pH. The model was calibrated using one experimental condition at a recycling ratio (R)=10, and was validated with R equal to 2 and 0, with an organic concentration of 554±24 mg TOCL(-1), salinity of 24 g L(-1) and hydraulic retention time (HRT) of 2 d. Carbon total removal is higher than 98%, while maximum nitrogen removal is 62% using total nitrification in the aerobic zone, due to a higher quantity of NO(x) produced which were recirculated to the anoxic zone. In the aerobic zone, simultaneous nitrification and denitrification processes occur, because the diffusion limitations cause a low oxygen penetration in the biofilm. In the anoxic-anaerobic zone, denitrification or methanogenesis inhibition by DO (caused by the recycled oxygen) is not observed.


Assuntos
Reatores Biológicos/microbiologia , Modelos Biológicos , Compostos Orgânicos/metabolismo , Compostos de Amônio Quaternário/metabolismo , Ultrafiltração/instrumentação , Purificação da Água/instrumentação , Simulação por Computador , Desenho Assistido por Computador , Desnitrificação/fisiologia , Desenho de Equipamento , Análise de Falha de Equipamento , Nitrificação/fisiologia , Oxirredução , Compostos de Amônio Quaternário/isolamento & purificação
8.
Eur. j. psychiatry ; 24(1): 46-58, ene.-mar. 2010. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-85593

RESUMO

Background and Objectives: Prior research suggests that marital dissatisfactionis associated with Major Depression (MD). The purpose of this study was to investigatewhether remission from a first episode of MD is associated with improvement inmarital dissatisfaction and whether the degree of marital dissatisfaction at the time of diagnosishas an influence on the outcome of MD.Methods: The Hamilton Rating Scale for Depression, the Dyadic Adjustment Scaleand the Areas of Change Questionnaire were administered to 59 married couples in whichone member fulfilled DSM-IV criteria for a first Episode of MD, but her husband (or hiswife) did not suffer any mental disorder, and to 53 control couples at 6 outpatient clinics,at baseline and after a 6-months follow-up.Results: The level of marital dissatisfaction in couples with a persistent depressed participantdecreased in comparison to couples without a depressed subject (p < 0.05 CI: -10.6 and -0.2), but there were no significant differences between couples in which the depressedspouse recovered from MD and comparison couples. Regardless of MD’s severity,high levels of satisfaction were associated with a higher probability to recover.Limitations: The follow-up period was short and we assessed the level of marital dissatisfactionusing self-report measures (AU)


Assuntos
Humanos , Transtorno Depressivo Maior/psicologia , Casamento/psicologia , Estudos Longitudinais , Estresse Psicológico , Relações Interpessoais , Conflito Familiar/psicologia
9.
La Paz; MDH/SNS/UDO; ago. 1995. 7 p.
Monografia em Espanhol | LIBOCS, LIBOSP | ID: biblio-1303163

RESUMO

El reglemento específico de ejecución de fondos de cooperación internacional, tiene como objetivos. a) Servir como marco conceptual b) Establecer elementos esenciales para la ejecución de adquisiciones y contratación de bienes y servicios con financiamiento externo. El reglamento específico de ejecución de Fondos de Cooperación Internacional, será aplicada a todas las entidades dependientes de la Secretaría Nacional de Salud como son las: Secretarias Regionales, Hospitales, Institutos, Centros de Salud, Direcciones, Proyectos y Programas (en adelante Unidad Ejecutora)


Assuntos
Humanos , Cooperação Internacional , Financiamento da Assistência à Saúde
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