The possible importance of synchrotron/inverse Compton losses to explain fast mm-wave and hard X-ray emission of a solar event

The solar burst of 21 May 1984, presented a number of unique features. The time profile consisted of seven major structures (seconds), with a turnover frequency of greater than or approximately 90 GHz, well correlated in time to hard X-ray emission. Each structure consisted of multiple fast pulses (0.1 seconds), which were analyzed in detail. A proportionality between the repetition rate of the pulses and the burst fluxes at 90 GHz and greater than or approximately 100 keV hard X-rays, and an inverse proportionality between repetition rates and hard X-ray power law indices were found. A synchrotron/inverse Compton model was applied to explain the emission of the fast burst structures, which appear to be possible for the first three or four structures

The possible importance of synchrotron/inverse Compton losses to explain fast MM-wave and hard X-ray emission of a solar event

The solar burst of 21 May 1984 presented a number of unique features. The time profile consisted of seven major structures (seconds), with a turnover frequency or approx. 90 GHz, well correlated in time to hard X-ray emission. Each structure consisted of multiple fast pulses (.1 seconds), which were analyzed in detail. A proportionality between the repetition rate of the pulses and the burst fluxes at 90 GHz and or approx. 100 keV hard X-rays, and an inverse proportionality between repetition rates and hard X-rays power law indices have been found. A synchrotron/inverse Compton model has been applied to explain the emission of the fast burst structures, which appear to be possible for the first three or four structures

A new class of solar burst with MM-wave emission but only at the highest frequency (90 GHz)

High sensitivity and high time resolution solar observations at 90 GHz (lambda = 3.3 mm) have identified a unique impulsive burst on May 21, 1984 with emission that was more intense at this frequency than at lower frequencies. The first major time structure of the burst was over 10 times more intense at 90 GHz than at 30 GHz, 7 GHz, or 2.8 GHz.Only 6 seconds later, the 30 GHz impulsive structures started to be observed but still with lower intensity than at 90 GHz. Hard X-ray time structures at energies above 25 keV were almost identical to the 90 GHZ structures (to better than one second). All 90 GHz major time structures consisted of trains of multiple subsecond pulses with rise times as short as 0.03 sec and amplitudes large compared to the mean flux. When detectable, the 30 GHz subsecond pulses had smaller relative amplitude and were in phase with the corresponding 90 GHz pulses

Multiple energetic injections in a strong spike-like solar burst

An intense and fast spike-like solar burst was built up of short time scale structures superimposed on an underlying gradual emission, the time evolution of which shows remarkable proportionality between hard X-ray and microwave fluxes. The finer time structure were best defined at mm-microwaves. At the peak of the event, the finer structures repeat every 30x60ms. The more slowly varying component with a time scale of about 1 second was identified in microwave hard X-rays throughout the burst duration. It is suggested that X-ray fluxes might also be proportional to the repetition rate of basic units of energy injection (quasi-quantized). The relevant parameters of one primary energy release site are estimated both in the case where hard X-rays are produced primarily by thick-target bremsstrahlung, and when they are purely thermal. The relation of this figure to global energy considerations is discussed

Evaluation of the optical switching characteristics of erbium-doped fibres for the development of a fibre Bragg grating sensor interrogator

A polling topology that employs optical switching based on the properties of erbium-doped fibres (EDFs) is used to interrogate an array of FBGs. The properties of the EDF are investigated in its pumped and un-pumped states and the EDFs’ switching properties are evaluated by comparing them with a high performance electronically controlled MEM optical switch. Potential advantages of the proposed technique are discussed. © (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

Igualdad de género bajo asedio: Percepciones y satisfacción de mujeres en teletrabajo con la distribución del trabajo no remunerado durante el cierre de Covid-19

This study analyses the impact of the Covid-19 pandemic on the division of domestic work as regards women in opposite-gender relationships, telecommuting and living as a couple, during the first lockdown in Portugal. Quantitative and qualitative data was collected (N=171) to understand women's perceptions of time spent on unpaid work, satisfaction, and main difficulties in this period. Results revealed women's dissatisfaction, especially mothers of underage children, who perceived an increase in caregiving tasks. Women's satisfaction also impacted their perception of the causes for these gender asymmetries. The less satisfied women ascribe gender inequalities mainly to socio-normative factors and gender stereotypes, while the more satisfied women ascribe them to aspects of socialisation and upbringing, as well as innate dispositions that differ between men and women. The trend towards more equality found prior to Covid-19 was not found.Este estudo analisa o impacto da pandemia de Covid-19 na divisão do trabalho doméstico de mulheres em relações com o sexo oposto, em teletrabalho e a viver em casal, durante o primeiro confinamento em Portugal. Recolheram-se dados quantitativos e qualitativos (N = 171) para compreender as perceções das mulheres sobre o tempo gasto em trabalho não remunerado, a satisfação e as principais dificuldades. Os resultados revelaram a insatisfação das mulheres, especialmente mães de crianças menores, que viram aumentar as tarefas de prestação de cuidados. A satisfação das mulheres também mostrou diferenças na perceção das causas destas assimetrias de género. As mulheres menos satisfeitas atribuem as desigualdades de género principalmente a fatores socionormativos e estereótipos de género, enquanto as mulheres mais satisfeitas as atribuem a aspetos de socialização e educação, bem como a disposições inatas que diferem entre homens e mulheres. A tendência de maior igualdade encontrada antes da Covid-19 não foi observada.info:eu-repo/semantics/publishedVersio

A fruticultura como vetor de desenvolvimento: o caso dos municipios de Petrolina (PE) e Juazeiro (BA).

Para contrapor o fenomeno das secas, que frequentemente provocam perda da producao agricola na zona semi-arida do Nordeste, gerando grandes problemas sociais, o governo tem implantado diversos perimetros publicos irrigados e promovido outros estimulos governamentais para a iniciativa privada no setor agropecuario. Atraves dessas iniciativas, o governo tem criado importantes Polos de producao agricola no que diz respeito as pequenas, medias e grandes empresas de producao de frutas e hortalicas. A agricultura irrigada e, mais especificamente, a fruticultura irrigada, promoveu um grande dinamismo na economia do Polo na estrutura urbana tornando-se o aglomerado urbano mais prospero do Vale do Sao Francisco. As grandes mudancas dos sistemas produtivos de culturas anuais para fruteiras perenes, de exportacao, desencadeou no Polo de Petrolina (PE)/Juazeiro (BA) demanda de outros investimentos de apoio para a comercializacao de frutas, motivando o Governo Federal a financiar pesquisas, priorizando aquelas relacionadas com culturas de exportacao, promover cursos de especializacao em comercio exterior e melhorar a infra-estrutura logistica da regiao. A fruticultura irrigada e o principal vetor do desenvolvimento do Submedio Sao Francisco, notadamente das suas cidades Polo, Petrolin,a e Juazeiro, que se constituem em verdadeiros "paraisos"de desenvolvimento dentro do Semi-arido brasileiro. Isto porque com o crescimento da fruticultura se desencadeou uma sinergia de crescimento em praticamente todos os setores produtivos, como o industrial, comercio e turismo. O objetivo deste trabalho e analisar a evolucao do Polo e pontos de estrangulamentos para a ampliacao do desenvolvimento da regiao

Rare cardiac tumor simulating ST elevated acute myocardial infarction

info:eu-repo/semantics/publishedVersio

Palaeomagnetism, rock magnetism and AMS of the Cabo Magmatic Province, NE Brazil, and the opening of South Atlantic

P>Reconstruction of the South Atlantic opening has long been a matter of debate and several models have been proposed. One problem in tracing properly the Atlantic history arises from the existence of a long interval without geomagnetic reversals, the Cretaceous Normal Superchron, for which ages are difficult to assign. Palaeomagnetism may help in addressing this issue if high-quality palaeomagnetic poles are available for the two drifting continental blocks, and if precise absolute ages are available. In this work we have investigated the Cabo Magmatic Province, northeastern Brazil, recently dated at 102 +/- 1 Ma (zircon fission tracks, Ar39/Ar40). All volcanic and plutonic rocks showed stable thermal and AF demagnetization patterns, and exhibit primary magnetic signatures. AMS data also support a primary origin for the magnetic fabric and is interpreted to be contemporaneous of the rock formation. The obtained pole is located at 335.9 degrees E/87.9 degrees S (N = 24; A(95) = 2.5; K = 138) and satisfies modern quality criteria, resulting in a reference pole for South America at similar to 100 Ma. This new pole also gives an insight to test and discuss the kinematic models currently proposed for the South Atlantic opening during mid-Cretaceous

Stellar parameters for stars of the CoRoT exoplanet field

Aims:To support the computation and evolutionary interpretation of periods associated with the rotational modulation, oscillations, and variability of stars located in the CoRoT fields, we are conducting a spectroscopic survey for stars located in the fields already observed by the satellite. These observations allow us to compute physical and chemical parameters for our stellar sample. Method: Using spectroscopic observations obtained with UVES/VLT and Hydra/Blanco, and based on standard analysis techniques, we computed physical and chemical parameters ($T_{\rm{eff}}$, $\log \,(g)$, $\rm{[Fe/H]}$, $v_{\rm{mic}}$, $v_{\rm{rad}}$, $v \sin \,(i)$, and $A(\rm{Li})$) for a large sample of CoRoT targets. Results: We provide physical and chemical parameters for a sample comprised of 138 CoRoT targets. Our analysis shows the stars in our sample are located in different evolutionary stages, ranging from the main sequence to the red giant branch, and range in spectral type from F to K. The physical and chemical properties for the stellar sample are in agreement with typical values reported for FGK stars. However, we report three stars presenting abnormal lithium behavior in the CoRoT fields. These parameters allow us to properly characterize the intrinsic properties of the stars in these fields. Our results reveal important differences in the distributions of metallicity, $T_{\rm eff}$, and evolutionary status for stars belonging to different CoRoT fields, in agreement with results obtained independently from ground-based photometric surveys. Conclusions: Our spectroscopic catalog, by providing much-needed spectroscopic information for a large sample of CoRoT targets, will be of key importance for the successful accomplishment of several different programs related to the CoRoT mission, thus it will help further boost the scientific return associated with this space mission.Comment: 43 pages, 17 figures, accepted for publication in A&