Helium Line Formation and Abundance in a Solar Active Region

An observing campaign (SOHO JOP 139), coordinated between ground-based and Solar and Heliospheric Observatory (SOHO) instruments, has been planned to obtain simultaneous spectroheliograms of the same active region in several spectral lines. The chromospheric lines Ca ii K, H , and Na i D, as well as He i 10830, 5876, 584, and He ii 304 8 lines have been observed. The EUV radiation in the range k < 500 8 and in the range 260 < k < 340 8 has also been measured at the same time. These simultaneous observations allow us to build semiempirical models of the chromosphere and low transition region of an active region, taking into account the estimated total number of photoionizing photons impinging on the target active region and their spectral distribution. We obtained a model that matches very well all the observed line profiles, using a standard value for the He abundance (½He ¼ 0:1) and a modified distribution of microturbulence. For this model we study the influence of the coronal radiation on the computed helium lines. We find that, even in an active region, the incident coronal radiation has a limited effect on the UV He lines, while it is of fundamental importance for the D3 and 10830 8 lines. Finally, we build two more models, assuming values of He abundance ½He ¼ 0:07 and 1.5, only in the region where temperatures are >1 ; 104 K. This region, between the chromosphere and transition region, has been indicated as a good candidate for processes that might be responsible for strong variations of [He]. The set of our observables can still be well reproduced in both cases, changing the atmospheric structure mainly in the low transition region. This implies that, to choose between different values of [He], it is necessary to constrain the transition region with different observables, independent of the He lines.Fil: Mauas, Pablo Jacobo David. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Andretta, V.. Osservatorio Astronomico di Capodimonte; ItaliaFil: Falchi, A.. Osservatorio Astrofisico di Arcetri; ItaliaFil: Falciani, R.. Universita Degli Studi Di Firenze; ItaliaFil: Teriaca, L.. Max-Planck-Institut fur Sonnensystemforschung; AlemaniaFil: Cauzzi, G.. Osservatorio Astrofisico di Arcetri; Itali

RHESSI images and spectra of two small flares

We studied the evolution of two small flares (GOES class C2 and C1) that developed in the same active region with different morphological characteristics: one is extended and the other is compact. We analyzed the accuracy and the consistency of different algorithms implemented in RHESSI software to reconstruct the image of the emitting sources, for energies between 3 and 12 keV. We found that all tested algorithms give consistent results for the peak position whil the other parameters can differ at most by a factor 2. Pixon and Forward-fit generally converge to similar results but Pixon is more reliable for reconstructing a complex source. We investigated the spectral characteristics of the two flares during their evolution in the 3--25 keV energy band. We found that a single thermal model of the photon spectrum is inadequate to fit the observations and we needed to add either a non-thermal model or a hot thermal one.The non-thermal and the double thermal fits are comparable. If we assume a non-thermal model, the non-thermal energy is always higher than the thermal one.Only during the very final decay phase a single thermal model fits fairly well the observed spectrum.Comment: 26 pages, 11 figures, accepted by Solar Physic

Eficiência alimentar entre novilhos Nelore confinados em diferentes instalações.

O objetivo do trabalho é avaliar o efeito de diferentes instalações na eficiência alimentar de bovinos de corte confinados

Consumo alimentar residual como índice de eficiência alimentar e suas implicações na qualidade de carne de novilhos Nelore.

A eficiência alimentar caracteriza-se como uma medida bruta obtida através da razão entre o consumo e o ganho de peso. Por ser correlacionada com peso vivo, pode apresentar limitações de utilização como parâmetro de identificação de animais eficientes por promover aumento no tamanho adulto do rebanho. Um índice alternativo de eficiência que não levaria este aumento é o Consumo Alimentar Residual (CAR). Porém, há indícios que este índice esteja associado a mudanças na composição corporal, onde os animais mais eficientes tendem a apresentar carcaças com menor espessura de gordura de acabamento e intramuscular. Este ensaio é parte do projeto ?Estratégias genéticas para melhoria da eficiência de produção e qualidade de carne bovina no Brasil? (Sistema Embrapa de Gestão - Macroprograma 1), no qual em três anos serão avaliados geneticamente 800 novilhos, filhos de 30 touros selecionados do sumário Nacional de Touros da raça Nelore. O objetivo desta proposta será avaliar, em dois anos, as relações entre CAR, características de carcaça e qualidade de carne de 300 novilhos Nelore. Em cada ano serão confinados 150 novilhos castrados, com 18 meses de idade. A dieta irá conter 14,7% de proteína bruta e 74,1% de nutrientes digestíveis totais. Serão avaliados consumo, ganho de peso, CAR, características de carcaça, qualidade de carne e as respectivas correlações fenotípicas. Todas as mensurações de desempenho animal e de qualidade de carne serão avaliadas mediante análise de variância. As médias obtidas nas classes de CAR (alto, médio ou baixo) serão comparadas pelo teste de Tukey a 5% de probabilidade. Os coeficientes de correlação entre as variáveis serão obtidos através do procedimento CORR do SAS (2002). Espera-se que o CAR possa ser utilizado como ferramenta para permitir a seleção de animais eficientes sem comprometer a qualidade da carne

Avaliação da homogeneidade da mistura de dietas de bovinos confinados com diferentes ingredientes.

Objetivou-se avaliar a qualidade da mistura de duas dietas, homogeneizadas em vagão misturador (Tratomix 600, IPACOL), por meio da análise de MS

Sister Mary Joseph's Nodule at a University Teaching Hospital in Northwestern Tanzania: A Retrospective Review of 34 cases.

Sister Mary Joseph's nodule is a metastatic tumor deposit in the umbilicus and often represents advanced intra-abdominal malignancy with dismal prognosis. There is a paucity of published data on this subject in our setting. This study was conducted to describe the clinicopathological presentation and treatment outcome of this condition in our environment and highlight challenges associated with the care of these patients, and to proffer solutions for improved outcome. This was a retrospective study of histologically confirmed cases of Sister Mary Joseph's nodule seen at Bugando Medical Centre between March 2003 and February 2013. Data collected were analyzed using descriptive statistics. A total of 34 patients were enrolled in the study. Males outnumbered females by a ratio of 1.4:1. The vast majority of patients (70.6%) presented with large umbilical nodule > 2 cm in size. The stomach (41.1%) was the most common location of the primary tumor. Adenocarcinoma (88.2%) was the most frequent histopathological type. Most of the primary tumors (52.9%) were poorly differentiated. As the disease was advanced and metastatic in all patients, only palliative therapy was offered. Out of 34 patients, 11 patients died in the hospital giving a mortality rate of 32.4%. Patients were followed up for 24 months. At the end of the follow-up period, 14(60.9%) patients were lost to follow-up and the remaining 9 (39.1%) patients died. Patients survived for a median period of 28 weeks (range, 2 to 64 weeks). The nodule recurred in 6 (26.1%) patients after complete excision. Sister Mary Joseph's nodule of the umbilicus is not rare in our environment and often represents manifestation of a variety of advanced intra-abdominal malignancies. The majority of the patients present at a late stage and many with distant metastases. The patient's survival is very short leading to a poor outcome. Early detection of primary cancer at an early stage may improve the prognosis

Existe preferência dos bovinos confinados por determinados cochos em sistema de alimentação coletivo?

Objetivou-se com este trabalho avaliar a posição dos animais dentro das baias coletivas para determinar a taxa de fidelidade a um cocho por determinado animal. Havendo preferência, seria possível atribuir o colar mais adequado para cada animal e, com isso, reduzir o tempo de aprendizado

Efeito de diferentes instalações no desempenho de novilhos Nelore confinados.

O objetivo deste trabalho é verificar se as diferentes instalações podem interferir no desempenho de novilhos Nelore confinados

Novel antiproliferative chimeric compounds with marked histone deacetylase inhibitory activity

Given our interest in finding potential antitumor agents and in view of the multifactorial mechanistic nature of cancer, in the present work, taking advantage of the multifunctional ligands approach, new chimeric molecules were designed and synthesized by combining in single chemical entities structural features of SAHA, targeting histone deacetylases (HDACs), with substituted stilbene or terphenyl derivatives previously obtained by us and endowed with antiproliferative and pro-apoptotic activity. The new chimeric derivatives were characterized with respect to their cytotoxic activity and their effects on cell cycle progression on different tumor cell lines, as well as their HDACs inhibition. Among the other, trans -6 showed the most interesting biological profile, as it exhibited a strong pro-apoptotic activity in tumor cell lines in comparison with both of its parent compounds and a marked HDAC inhibition