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Continuous nonlinear transmission lines (NLTLs), also known as gyromagnetic lines, consist of ferrite-based magnetic cores biased by an external magnetic field. Over the past years, many analytical and experimental studies have predicted the rise time reduction of the input pulse to the range of a few nanoseconds or even hundreds of ps experimentally observed in such gyromagnetic lines. This effect, known as pulse sharpening, is investigated in this paper built on a model based on a periodic structure of inductive-capacitive cells in series with magnetization-driven voltage sources expressed by the one-dimensional form (1D) of the Landau-Lifshitz-Gilbert (LLG) gyromagnetic equation. We explore the model through parametric study under various input-pulse parameters to understand the physics behind the ferrimagnetic material responses. Moreover, the numerical results obtained from computational simulations using Mathematica (v. 12.1) show how the line parameters (input voltage, damping constant, saturation magnetization, and length) affect the sharpening effect, which is quantified by the switching time. Our results on ferrite-loaded coaxial lines have confirmed many results found in the literature. We validated with a good agreement the proposed model with the result obtained by Dolan in 1993 using the same 1D form of the LLG equation, thus showing that the model proposed here is suitable to quantify the sharpening effect produced by a gyromagnetic NLTL.
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BACKGROUND: Quality of life and psychological well-being are readily hampered by depression. The changes that students face during college life impact their psychological health and well-being, including the emergence of mental health problems like depression Aim: To determine the relationship between depressive symptoms, sociodemographic parameters and psychological well-being in undergraduate university students. MATERIAL AND METHODS: Five hundred eighty university students of both sexes, from the Metropolitan and IX Regions of Chile answered the Beck Depression Inventory (BDI-IA) and the Ryff's psychological well-being scale. RESULTS: Twenty eight percent of respondents had clinically significant depressive symptoms, and these were more frequent in women. There was an inverse and statistically significant relationship between psychological well-being and depressive symptoms. This fact was especially marked in dimensions of autonomy, positive relationships with others and purpose in life. CONCLUSIONS: There is a high frequency of depressive symptoms among these students. We discuss whether psychological well-being and depressive symptomatology represent two extremes within a continuum or they are two independent dimensions that can account for differential causal mechanisms linked to mental health and illness.
Assuntos
Depressão/epidemiologia , Qualidade de Vida/psicologia , Estudantes/psicologia , Adolescente , Adulto , Chile/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Distribuição por Sexo , Fatores Sexuais , Fatores Socioeconômicos , Universidades/estatística & dados numéricos , Adulto JovemRESUMO
Background: Quality of life and psychological well-being are readily hampered by depression. The changes that students face during college life impact their psychological health and well-being, including the emergence of mental health problems like depression Aim: To determine the relationship between depressive symptoms, sociodemographic parameters and psychological well-being in undergraduate university students. Material and Methods: Five hundred eighty university students of both sexes, from the Metropolitan and IX Regions of Chile answered the Beck Depression Inventory (BDI-IA) and the Ryff's psychological well-being scale. Results: Twenty eight percent of respondents had clinically significant depressive symptoms, and these were more frequent in women. There was an inverse and statistically significant relationship between psychological well-being and depressive symptoms. This fact was especially marked in dimensions of autonomy, positive relationships with others and purpose in life. Conclusions: There is a high frequency of depressive symptoms among these students. We discuss whether psychological well-being and depressive symptomatology represent two extremes within a continuum or they are two independent dimensions that can account for differential causal mechanisms linked to mental health and illness.
Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Adulto Jovem , Qualidade de Vida/psicologia , Estudantes/psicologia , Depressão/epidemiologia , Escalas de Graduação Psiquiátrica , Fatores Socioeconômicos , Universidades/estatística & dados numéricos , Chile/epidemiologia , Fatores Sexuais , Estudos Transversais , Distribuição por SexoRESUMO
Recent research in psychiatric genetics has led to a move away from simple diathesis-stress models to more complex models of psychopathology incorporating a focus on gene-environment interactions and epigenetics. Our increased understanding of the way biology encodes the impact of life events on organisms has also generated more sophisticated theoretical models concerning the molecular processes at the interface between "nature" and "nurture." There is also increasing consensus that psychotherapy entails a specific type of learning in the context of an emotional relationship (i.e., the therapeutic relationship) that may also lead to epigenetic modifications across different therapeutic treatment modalities. This paper provides a systematic review of this emerging body of research. It is concluded that, although the evidence is still limited at this stage, extant research does indeed suggest that psychotherapy may be associated with epigenetic changes. Furthermore, it is argued that epigenetic studies may play a key role in the identification of biomarkers implicated in vulnerability for psychopathology, and thus may improve diagnosis and open up future research opportunities regarding the mechanism of action of psychotropic drugs as well as psychotherapy. We review evidence suggesting there may be important individual differences in susceptibility to environmental input, including psychotherapy. In addition, given that there is increasing evidence for the transgenerational transmission of epigenetic modifications in animals and humans exposed to trauma and adversity, epigenetic changes produced by psychotherapy may also potentially be passed on to the next generation, which opens up new perspective for prevention science. We conclude this paper stressing the limitations of current research and by proposing a set of recommendations for future research in this area.
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A new method of Plasma Immersion Ion Implantation (PIII) and deposition (PIII and D) for treating industrial components in the batch mode has been developed. A metal tubular fixture is used to allocate the components inside, around, and along the tube, exposing only the parts of each component that are to be ion implanted to the plasma. Hollow cathode-like plasma is generated only inside the tube filled with the desired gas, by applying high negative voltage pulses to the hollow cylindrical fixture which is insulated from the vacuum chamber walls. This is a very convenient method of batch processing of industrial parts by ion implantation, in which a large number of small to medium sized components can be treated by PIII and PIII and D, very quickly, efficiently, and also at low cost.
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El carcinoma suprarrenal es una enfermedad infrecuente que afecta entre 0.45 a 2 personas cada millón. Relación mujer: hombre 2.7:1, con un promedio de edad de 45 años. Mayor compromiso de la glándula izquierda. En el 53% de los casos se diagnostica por síndromes funcionantes. El resto se expresa por efecto de masa o por detección de metástasis. Son fundamentales las imágenes y el testeo hormonal. Es muy agresivo, de mal pronóstico y generalmente avanzado al diagnóstico. A la fecha existen escasos recursos terapéuticos. A continuación, se presenta una paciente de 23 años con un cáncer de suprarrenal funcionante estadio IV.
The adrenal carcinoma is an infrequent disease that affects0.45 to 2 cases per millon population per year. Women aremore frequently affected than men (2.7:1), with an averageage of 45 years. More common is the commitment of theleft gland. In 53% of cases, functioning tumor exists. Therest are diagnosed from local tumour invasion. Images andhormonal laboratory are basic. It is very aggressive, withpoor prognosis and advanced at diagnosis. To date thereare few therapeutic resources. We present here a 23 yearsold patient with such diagnosis and metastatic stage.
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Humanos , Glândulas Suprarrenais , Carcinoma , Síndrome de Cushing , Acantose Nigricans , Acne Vulgar , Hirsutismo , Mitotano , Metástase NeoplásicaRESUMO
En los últimos años se ha producido un crecimiento explosivo en las tecnologías para la producción de imágenes médicas. El costo del procesamiento digital de alta capacidad se ha reducido considerablemente. Esto ha promocionado el uso de la visualización científica en muchas disciplinas donde los conjuntos de datos son complejos, ricos en calidad y sobrecogedores en cantidad. Cada vez es mayor el número de imágenes que se obtienen para caracterizar la anatomía y las funciones del cuerpo humano. Se hace indispensable la familiarización del médico con los métodos y sistemas que le permitirán analizar y manejar esta gran cantidad de información de una manera rápida y eficiente. En este artículo se revisan algunas técnicas básicas de procesamiento digital que tienen aplicación en un ambiente clínico que cuente con tecnologías de información adecuadas. A pesar de que se muestran aplicaciones para el estudio cerebral, las mismas técnicas pueden ser utilizadas en cualquier región anatómica de la que se pueda obtener una imagen.
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Diagnóstico por Imagem/métodos , Processamento de Imagem Assistida por Computador , Técnicas e Procedimentos Diagnósticos , Espectroscopia de Ressonância MagnéticaAssuntos
Humanos , Diagnóstico por Imagem/métodos , Processamento de Imagem Assistida por Computador , Procedimentos Cirúrgicos Operatórios/métodos , Diagnóstico por Imagem/história , Diagnóstico por Imagem/instrumentação , Diagnóstico por Imagem/tendências , Processamento de Imagem Assistida por Computador/história , Processamento de Imagem Assistida por Computador/instrumentaçãoAssuntos
Humanos , Masculino , Feminino , 1-Metil-3-Isobutilxantina , Asma/tratamento farmacológico , Beclometasona/uso terapêutico , Testes de Provocação Brônquica , Brônquios/efeitos dos fármacos , Tosse/etiologia , Nedocromil/farmacocinética , Nedocromil/uso terapêutico , Corticosteroides/uso terapêutico , Broncodilatadores/uso terapêutico , Pico do Fluxo Expiratório , Qualidade de Vida , EspirometriaRESUMO
Os autores estudaram experimentalmente 26 ossos semilunares de 13 cadáveres frescos, analisando medidas antropométricas e submetendo-os a ensaios de compressäo para verificar sua resistência. Obtiveram valores de resistência variando de 41 a 200kgf, com média de 102,1kgf, e correlacionaram com as medidas antropomêtricas.
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Osso Semilunar/fisiologia , Cadáver , Força Compressiva , Osso Semilunar/anatomia & histologiaRESUMO
En los últimos años ha habido una verdadera resolución en el desarrollo de los métodos de diagnóstico Neurorradiológico no invasivo. A pesar de esto la angiografía cerebral sigue siendo indispensable para el diagnóstico y evaluación de las enfermedades cerebro-vasculares y en otras patologías seleccionadas. El número de complicaciones ha sido reducido drásticamente pero aún se presentan, y es especialmente dramático cuando son de índole neurológico. En los últimos años hemos adoptado en nuestro Servicio una actitud mas agresiva en el estudio y tratamiento de estas complicaciones ya que nuestra experiencia previa con ellas era decepcionante. Se presentan cuatro casos de complicaciones angiográficas, todas ellas embólicas, y que ilustran la dificultad en su manejo. En dos de ellos se utilizó heparina intra-arterial, en uno se hizo una embolectomia quirúrgica y en el último caso se utilizó Estreptoquinasa intra-arterial selectiva con un buen resultado y recanalización parcial inmediata. Se concluye que es indispensable estudiar al enfermo que presenta una complicación angiográfica en forma inmediata ya que estos accidentes se producen en un ambiente especializado donde se pueden eventualmente tomar medidas terapéuticas que instauradas en forma precoz podrán evitar el infarto cerebral
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Isquemia Encefálica/terapia , Angiografia Cerebral/efeitos adversos , Embolia e Trombose Intracraniana/terapia , Hemorragia Subaracnóidea/complicações , Terapia Trombolítica/métodosRESUMO
Relata-se um caso de criptococose pulmonar e do sistema nervoso central, cujo esquema terapêutico utilizado constou de anfotericina B associada a 5-fluorocitosina (5FC), e ulterior ressecçäo de toruloma sediado em pulmäo. Tecem-se consideraçöes sobre as diferentes abordagens terapêuticas para a criptococose, propostas na literatura. Enfatizam-se que, em nosso meio, a criptococose tem incidência relativamente rara e o emprego da 5 FC é ainda pouco difundido. Observaram-se, também, que a abordagem cirúrgica de torulomas é assunto näo divulgado entre nós. Concluem-se, que o esquema utilizado mostrou-se plenamente satisfatório, com o paciente permanecendo totalmente assintomático já por mais de oito anos, em plena atividade profissional e sem quaisquer indícios (clínicos, laboratoriais e radiológicos) de recidivas
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Adulto , Humanos , Masculino , Anfotericina B/uso terapêutico , Criptococose/tratamento farmacológico , Flucitosina/uso terapêutico , Doenças do Sistema Nervoso Central/microbiologia , Pneumopatias Fúngicas/tratamento farmacológico , Criptococose/cirurgiaRESUMO
One hundred and fifty lepromatous patients of both sexes, with active lesions, were selected for this study trough clinical, baciloscopic and histopathological examinations. According to bacilloscopy, oral lesions involute simultaneously with skin lesions. For this study, clinical, bacilloscopic and histopathological examinations were meda, besides photographs of the most suggstive cases.