Solar type II radio bursts associated with CME expansions as shown by EUV waves

We investigate the physical conditions of the sources of two metric Type-II bursts associated with CME expansions with the aim of verifying the relationship between the shocks and the CMEs, comparing the heights of the radio sources and the heights of the EUV waves associated with the CMEs. The heights of the EUV waves associated with the events were determined in relation to the wave fronts. The heights of the shocks were estimated by applying two different density models to the frequencies of the Type-II emissions and compared with the heights of the EUV waves. For the 13 June 2010 event, with band-splitting, the shock speed was estimated from the frequency drifts of the upper and lower branches of the harmonic lane, taking into account the H/F frequency ratio fH/fF = 2. Exponential fits on the intensity maxima of the branches revealed to be more consistent with the morphology of the spectrum of this event. For the 6 June 2012 event, with no band-splitting and with a clear fundamental lane on the spectrum, the shock speed was estimated directly from the frequency drift of the fundamental emission, determined by linear fit on the intensity maxima of the lane. For each event, the most appropriate density model was adopted to estimate the physical parameters of the radio source. The 13 June 2010 event presented a shock speed of 664-719 km/s, consistent with the average speed of the EUV wave fronts of 609 km/s. The 6 June 2012 event was related to a shock of speed of 211-461 km/s, also consistent with the average speed of the EUV wave fronts of 418 km/s. For both events, the heights of the EUV wave revealed to be compatible with the heights of the radio source, assuming a radial propagation of the shock.Comment: Accepted for publication in Astronomy and Astrophysic

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

Levantamento de vírus em lavouras de alho o Brasil.

O presente trabalho teve o objetivo de realizar a diagnose viral em amostras de alho provenientes de lavouras localizadas nos municípios de Planaltina - DF, Cristópolis - BA, Mirangaba - BA e Bueno Brandão - MG

Diversidade viral associada à batata-doce no banco ativo de germoplasma da Embrapa Hortaliças.

Realizou-se um levantamento de vírus no Banco Ativo de Germoplasma de batata-doce da Embrapa Hortaliças

Teores de peróxido de hidrogênio em extratos de folhas de bananeira na presença do fungo Mycosphaerella fijiensis.

A banana (Musa spp.) é uma das frutas mais consumidas no mundo, tendo o Brasil como um dos maiores produtores e consumidores. Embora bem adaptada as condições edafoclimáticas, a bananeira sofre o ataque de inúmeros patógenos, onde destaca-se a Mycosphaerella fijiensis, agente causal da sigatoka negra. Para se defender, as plantas lançam mão de um arsenal de defesa, sendo a resposta hipersensitiva a primeira etapa deste mecanismo, marcada pelo acúmulo de peróxido de hidrogênio. Com o objetivo de avaliar o papel do peróxido de hidrogênio neste patossistema, foram utilizadas 3 variedades de bananas, sendo duas consideradas resistentes e ou tolerante a sigatoka negra, a FHIA-18 e BRS Garantida, e outra variedade considerada susceptível, Maçã. As variedades foram inoculadas com uma suspensão de esporos e as folhas coletadas 0, 24, 48, 72, 96, 120 horas e 15 dias da inoculação (hai), as quais foram utilizadas na determinação dos teores de peróxido de hidrogênio. Os teores de H2O2 variaram de 0,19 a 0,47 nmolH2O2 nas plantas controle e de 0,14 a 1,30 nmolH2O2 nas plantas inoculadas, na variedade Maçã. A variedade FHIA-18 apresentou teores variando de 0,31 a 1,53 nmolH2O2 nas plantas controle e de 0,08 a 0,56 nmolH2O2 nas plantas inoculadas. Na variedade BRS Garantida, os valores variaram de 0,19 a 0,72 nmolH2O2 nas plantas controle e de 0,13 a 0,50 nmolH2O2 nas plantas inoculadas. Os resultados alcançados até o momento sugerem a participação do peróxido de hidrogênio no mecanismo de defesa da bananeira contra o ataque do fungo M. fijiensis

Doenças do feijoeiro-comum em Rondônia.

Descreve-se as principais doenças ocorrentes no pólo feijoeiro de Rondônia e demais municípios do Estado, onde o cultivo do “feijoeiro da seca” é explorado no período de fevereiro a junho.bitstream/item/24797/1/rt93-feijao.pd

Avaliação de parâmetros bioquímicos da interação entre Mycosphaerella fijiensis e Musa sp.

A bananeira é uma fruteira com grande valor comercial, sendo de fácil adaptação somente em regiões tropicais. Entretanto, esta cultura sofre o ataque de uma doença conhecida como sigatoka negra tendo como agente causal o fungo Mycosphaerella fijiensis. Esta doença pode causar prejuízos de até 100% na produção e, depois de instalada, provoca aumento significativo nos custos de produção, pois serão necessárias mais de trinta aplicações de produto químico por ano, trazendo impactos econômicos e ambientais. Para se defenderem do ataque de fitopatógenos, as plantas estão utilizam defesas constitutivas, naturalmente presentes na planta, funcionando como barreiras físicas, tais como a cutícula e os tricomas, e barreiras químicas, incluindo os inibidores de proteases e fenóis, e as defesas induzidas, como as PR-Proteínas e enzimas ligadas as estresse oxidativo. Este trabalho relata as avaliações bioquímicas decorrentes da interação entre o fungo M. fijiensis e Musa sp., demonstrando os níveis de atividades de enzimas ligadas ao mecanismo de defesa da bananeira, tais como peroxidase, ascorbato peroxidase, catalase, fenilalanina amônia liase. Os resultados obtidos indicam a participação destas enzimas no mecanismo de defesa da bananeira contra o fungo M. fijiensis

Levantamento da diversidade de vírus em batata-doce no Brasil.

O presente trabalho teve o objetivo de realizar um levantamento de vírus no Banco ativo de Germoplasma de batata-doce da Embrapa Hortaliaças

Does body mass index influence surgical options and overall survival in breast cancer patients?

Obesity is a relevant risk factor in breast cancer (BC), but little is known about the effects of overweight and obesity in surgical outcomes of BC patients. The aim of this study is to analyse surgical options and associated overall survival (OS) in overweight and obese women with BC. In this study, 2143 women diagnosed between 2012 and 2016 at the Portuguese Oncology Institute of Porto (IPO-Porto) were included, and the clinicopathological information was retrieved from the institutional database. Patients were stratified by body mass index (BMI). Statistical analysis included Pearson's chi-squared test with statistical significance set at p < 0.05. Multinomial, binary logistic regression and cox proportional-hazards model were also performed to calculate odd ratios and hazard ratios with 95% confidence intervals for adjusted and non-adjusted models. The results revealed no statistical difference in histological type, topographic localization, tumour stage and receptor status and in the number of surgical interventions. Overweight women have increased probability to be subjected to sentinel node biopsy. Obese and overweight women are more likely to be submitted to conservative surgery and contrariwise, less likely to undergo total mastectomy. Patients submitted to conservative surgery and not submitted to total mastectomy had a favourable OS although without statistical significance. No significant differences were observed in OS when stratified by BMI. Our results revealed significant variations regarding the surgical options in overweight and obese patients, but these were not translated in OS difference. More research is recommended to better address treatment options in overweight and obese BC patients.Open access funding provided by FCT vertical bar FCCN (b-on). This research was supported by the FCT - Fundacao para a Ciencia e Tecnologia by a scholarship granted to Carla Luis (SFRH/BD/146489/2019)