Photoassociative ionization of Na inside a storage ring

Motivated by recent interest in low dimensional arrays of atoms, we experimentally investigated the way cold collisional processes are affected by the geometry of the considered atomic sample. More specifically, we studied the case of photoassociative ionization (PAI) both in a storage ring where collision is more unidirectional in character and in a trap with clear undefinition of collision axis. First, creating a ring shaped trap (atomotron) we investigated two-color PAI dependence with intensity and polarization of a probing laser. The intensity dependence of the PAI rate was also measured in a magneto-optical trap presenting equivalent temperature and density conditions. Indeed, the results show that in the ring trap, the value of the PAI rate constant is much lower and does not show evidences of saturation, unlike in the case of the 3D-MOT. Cold atomic collisions in storage ring may represent new possibilities for study.Comment: 5 pages, 5 figures; Accepted by Optics Communicatio

Avaliação da qualidade da madeira através de infravermelho próximo (NIRS).

Resumo

Collective excitation of a Bose-Einstein condensate by modulation of the atomic scattering length

We excite the lowest-lying quadrupole mode of a Bose-Einstein condensate by modulating the atomic scattering length via a Feshbach resonance. Excitation occurs at various modulation frequencies, and resonances located at the natural quadrupole frequency of the condensate and at the first harmonic are observed. We also investigate the amplitude of the excited mode as a function of modulation depth. Numerical simulations based on a variational calculation agree with our experimental results and provide insight into the observed behavior.Comment: Submitted to PR

Magnetic reconfiguration of MnAs/GaAs(001) observed by Magnetic Force Microscopy and Resonant Soft X-ray Scattering

We investigated the thermal evolution of the magnetic properties of MnAs epitaxial films grown on GaAs(001) during the coexistence of hexagonal/orthorhombic phases using polarized resonant (magnetic) soft X-ray scattering and magnetic force microscopy. The results of the diffuse satellite X-ray peaks were compared to those obtained by magnetic force microscopy and suggest a reorientation of ferromagnetic terraces as temperature rises. By measuring hysteresis loops at these peaks we show that this reorientation is common to all ferromagnetic terraces. The reorientation is explained by a simple model based on the shape anisotropy energy. Demagnetizing factors were calculated for different configurations suggested by the magnetic images. We noted that the magnetic moments flip from an in-plane mono-domain orientation at lower temperatures to a three-domain out-of-plane configuration at higher temperatures. The transition was observed when the ferromagnetic stripe width L is equal to 2.9 times the film thickness d. This is in good agreement with the expected theoretical value of L = 2.6d.Comment: 16 pages in PD

MULTIDISCIPLINARY APPROACH AND QUALITY OF LIFE IN PATIENTS WITH SPINA BIFIDA

Introdução: A Espinha Bífida é o defeito mais comum do tubo neural. A abordagem multidisciplinar é a mais adequada para prestar cuidados a estes doentes. Objetivo: Caracterizar a população de crianças seguida na consulta multidisciplinar de Espinha Bífida de um Hospital Terciário. Avaliar a perceção da qualidade de vida das crianças, adolescentes e pais/cuidadores. Correlacionar a qualidade de vida com algumas variáveis estudadas. Métodos: Estudo retrospetivo que incluiu as crianças em seguimento na consulta multidisciplinar de Espinha Bífida. As variáveis analisadas foram: tipo de defeito do tubo neural, regime vesico-esfincteriano e nível funcional. A avaliação da qualidade de vida foi feita através da aplicação do questionário Child Health Questionnaire – Parental Form (CHQ – PF50). O tratamento estatístico foi realizado no programa SPSS, versão 17. Resultados: Foram incluídas no estudo 69 crianças. Os doentes apresentavam uma idade média de 13 anos, sendo 52,2% do sexo masculino. Oitenta e seis por cento tinham diagnóstico de mielomeningocelo, 56,5% efetuavam marcha de forma autónoma e 30,4% eram incontinentes necessitando do uso de fralda. O questionário de qualidade de vida foi respondido pelos pais de 31 doentes. Todos os scores apresentaram valores superiores a 50, sendo que os que revelaram valores menores foram o relativo à função física nas crianças e o referente ao impacto emocional nos pais. Foi encontrada uma correlação estatisticamente significativa entre a capacidade funcional e o componente da escala de qualidade de vida relativo ao funcionamento físico (r = 0,456; p =0,01). Conclusão: As várias manifestações clínicas e complicações associadas a esta condição podem interferir de forma significativa nos vários componentes da qualidade de vida dos doentes e seu núcleo familiar. Este trabalho sublinha a importância da avaliação e intervenção das necessidades das crianças com incapacidade de forma a promover o seu bem-estar físico, psicológico e social.Introduction: Spina Bifida is the most common neural tube defect. Multidisciplinary approach has long been advocated as the optimal way to provide care for these patients. Aim: To characterize the population of children followed in Spina Bifida clinic. To measure health-related quality of the life of children, adolescents and care givers. To correlate quality of life with some studied variables. Methods: Retrospective study that included children followed in Spina Bifida clinic. The variables analyzed were: regarding the type of neural tube defect, bladder-sphincter system and functional level. The quality of life was assessed through the application of the questionnaire Child Health Questionnaire - Parental Form (CHQ – PF50). The statistical analysis was made with SPSS, version 17. Results: The study included 69 children. Patients had a mean age of 13 years, 52.2% male, 86% had a diagnosis of myelomeningocele, 56.5% had independent gait and 30.4% were incontinent and used a diaper. The quality of life questionnaire was completed by 31 parents. All scores were greater than 50, the lowest value in patients was physical function and in parents was emotional impact. We found a statistically significant correlation between functional capacity and physical functioning score on quality of life scale (r = 0.456, p = 0.01). Conclusion: Clinical manifestations and complications of this condition can interfere significantly in the various components of patients’ and families’ quality of life. This study emphasizes the importance of assessment and measurement of needs in children with disabilities in order to promote their physical, psychological and social well-being

Manejo de Pastagens de Brachiaria dictyoneura na Amazônia Ocidental.

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Recuperação de áreas degradadas com tração animal.

Avaliou-se o efeito da tração animal no aproveitamento de áreas degradadas em propriedades que praticam a agricultura familiar

Produção de leite de búfalas na agricultura familiar em Rondônia.

Avaliou-se a criação de búfalos em propriedades que praticam agricultura familiar incentivando a produção de leite para o sustento familiar, o aproveitamento de adubo orgânico e o aproveitamento de áreas degradadas