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1.
Sol Phys ; 295(2): 18, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32109973

RESUMO

We report on the source of > 300 MeV protons during the SOL2014-09-01 sustained gamma-ray emission (SGRE) event based on multi-wavelength data from a wide array of space- and ground-based instruments. Based on the eruption geometry we provide concrete explanation for the spatially and temporally extended γ -ray emission from the eruption. We show that the associated flux rope is of low inclination (roughly oriented in the east-west direction), which enables the associated shock to extend to the frontside. We compare the centroid of the SGRE source with the location of the flux rope's leg to infer that the high-energy protons must be precipitating between the flux rope leg and the shock front. The durations of the SOL2014-09-01 SGRE event and the type II radio burst agree with the linear relationship between these parameters obtained for other SGRE events with duration ≥ 3 hrs . The fluence spectrum of the SEP event is very hard, indicating the presence of high-energy (GeV) particles in this event. This is further confirmed by the presence of an energetic coronal mass ejection with a speed > 2000 km s - 1 , similar to those in ground level enhancement (GLE) events. The type II radio burst had emission components from metric to kilometric wavelengths as in events associated with GLE events. All these factors indicate that the high-energy particles from the shock were in sufficient numbers needed for the production of γ -rays via neutral pion decay.

2.
J Atmos Sol Terr Phys ; 176: 26-33, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32021560

RESUMO

We use microwave imaging observations from the Nobeyama Radioheliograph at 17 GHz for long-term studies of solar activity. In particular, we use the polar and low-latitude brightness temperatures as proxies to the polar magnetic field and the active-regions, respectively. We also use the location of prominence eruptions as a proxy to the filament locations as a function of time. We show that the polar microwave brightness temperature is highly correlated with the polar magnetic field strength and the fast solar wind speed. We also show that the polar microwave brightness at one cycle is correlated with the low latitude brightness with a lag of about half a solar cycle. We use this correlation to predict the strength of the solar cycle: the smoothed sunspot numbers in the southern and northern hemispheres can be predicted as 89 and 59, respectively. These values indicate that cycle 25 will not be too different from cycle 24 in its strength. We also combined the rush to the pole data from Nobeyama prominences with historical data going back to 1860 to study the north-south asymmetry of sign reversal at solar poles. We find that the reversal asymmetry has a quasi-periodicity of 3-5 cycles.

3.
Obes Sci Pract ; 3(2): 212-218, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28702214

RESUMO

INTRODUCTION: Co­existing decreased muscle mass and increased visceral fat, an age­associated change called sarcopenic obesity, results in fragility and cardiovascular disease. To assess the pathogenesis of sarcopenic obesity, we assessed the associations of clinical parameters with psoas muscle mass in elderly male subjects with obesity and type 2 diabetes. METHODS: The subjects were 55 patients, over 65 years of age and with a visceral fat area exceeding 100 cm2, with type 2 diabetes. The cross­sectional area of the psoas muscle is considered to provide an estimation of overall muscle mass. Sarcopenia was considered to be present when the total psoas muscle area was low, defined as a value below 500 mm2 m−2 on a computed tomographic scan. RESULTS: The maximum intima­media thickness (max IMT) and urinary 8­isoprostane values were significantly higher in the sarcopenic group. Multiple linear regression analysis revealed max IMT to be an independent variable related to muscle mass decline. In addition, logistic analysis showed max IMT and urinary 8­isoprostane to be variables independently contributing to total psoas muscle area <500 mm2 m−2. CONCLUSION: Worsening surrogate markers for systemic oxidative stress and atherosclerosis were associated with declining muscle mass in elderly subjects with obesity and type 2 diabetes. These results indicate that systemic oxidative stress is among the mechanisms underlying atherosclerosis development in subjects with sarcopenic obesity.

4.
Radiat Prot Dosimetry ; 161(1-4): 274-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24344351

RESUMO

WASAVIES, a warning system for aviation exposure to solar energetic particles (SEPs), is under development by collaboration between several institutes in Japan and the USA. It is designed to deterministically forecast the SEP fluxes incident on the atmosphere within 6 h after flare onset using the latest space weather research. To immediately estimate the aircrew doses from the obtained SEP fluxes, the response functions of the particle fluxes generated by the incidence of monoenergetic protons into the atmosphere were developed by performing air shower simulations using the Particle and Heavy Ion Transport code system. The accuracy of the simulation was well verified by calculating the increase count rates of a neutron monitor during a ground-level enhancement, combining the response function with the SEP fluxes measured by the PAMELA spectrometer. The response function will be implemented in WASAVIES and used to protect aircrews from additional SEP exposure.


Assuntos
Radiação Cósmica , Exposição Ocupacional , Radiometria/instrumentação , Atividade Solar , Medicina Aeroespacial , Aeronaves , Algoritmos , Aviação , Simulação por Computador , Humanos , Japão , Nêutrons , Prótons , Doses de Radiação , Proteção Radiológica , Radiometria/métodos , Reprodutibilidade dos Testes , Estados Unidos
5.
Vet Pathol ; 39(4): 512-5, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12126158

RESUMO

A 7-year-old female Labrador Retriever dog showed extreme muscular weakness, muscle wasting, dysbasia, and mild dysphagia. An elevated value of creatine kinase (335 IU/liter) in the serum was detected. Electromyographic findings included increased insertional activity, fibrillation potentials, and bizarre high-frequency repetitive potentials. Histopathologic examination of skeletal muscles revealed myofiber necrosis and phagocytosis, regeneration of myofibers, and perivascular, perimysial, and endomysial infiltrations of lymphocytes, macrophages and plasma cells. Immunohistochemical evaluation demonstrated that infiltrative cells in the early stage of myositis were CD8+ T-cells and that an increased expression of major histocompatibility complex (MHC) class I was apparent on the surface of nonnecrotic muscle fibers. In contrast, many CD3+ cells (T cells) and HLA-DR-positive macrophages and B lymphocytes were found in the severely affected areas. These results suggest that both expression of MHC class I and CD8+ T-cell infiltration may play an important role in initiation of myositis. These histopathologic findings resemble those reported in naturally occurring polymyositis in humans.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Doenças do Cão/imunologia , Antígenos de Histocompatibilidade Classe I/biossíntese , Músculo Esquelético/imunologia , Polimiosite/veterinária , Animais , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Creatina Quinase/sangue , Doenças do Cão/metabolismo , Doenças do Cão/patologia , Cães , Eletromiografia/veterinária , Evolução Fatal , Feminino , Regulação da Expressão Gênica , Antígenos de Histocompatibilidade Classe I/metabolismo , Imuno-Histoquímica/veterinária , Músculo Esquelético/metabolismo , Polimiosite/imunologia , Polimiosite/metabolismo
6.
Nippon Ganka Gakkai Zasshi ; 105(7): 483-7, 2001 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-11510114

RESUMO

PURPOSE: To examine the ocular complications in patients infected with human immunodeficiency virus(HIV) in Japan. METHODS: The medical records of 322 patients seen at the acquired immunodeficiency syndrome(AIDS) Clinical Center from July 1, 1997 through December 31, 1998 were reviewed, and the HIV-associated ocular complications were correlated with serum CD 4+ T-lymphocyte counts. RESULTS: Ocular complications were found in 51 patients: 35 cases with retinal microvasculopathy, 17 cases with cytomegalovirus retinitis(9 quiescent, 6 active, and 2 recurrent), and 1 case each with tuberculous uveitis, phthisis bulbi after necrotizing herpetic retinopathy, conjunctival Kaposi's sarcoma, papilledema, divergence palsy, hemianopia, and abducens palsy. Retinal microvasculopathy was present in patients with CD 4+ T-lymphocyte counts above 500/mm3, but was more common in patients with cell counts below 200/mm3. Among 6 patients with active cytomegalovirus retinitis, 5 patients had a CD 4+ T-lymphocyte count below 50/mm3 at the onset of retinitis, while one patient developed retinitis after the cell count increased to over 200/mm3 with highly active antiretroviral therapy. CONCLUSION: Cytomegalovirus retinopathy may occur in patients with a CD 4+ T-lymphocyte count of more than 200/mm3.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS , Síndrome da Imunodeficiência Adquirida/complicações , Retinite por Citomegalovirus/etiologia , Oftalmopatias/etiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
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