342 research outputs found

    Characteristics of gravity waves generated in a convective and a non-convective environment revealed from hourly radiosonde observation under CPEA-II campaign

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    Analyses of hourly radiosonde data of temperature, wind, and relative humidity during four days (two with convection and two with no convection) as a part of an intensive observation period in CPEA-2 campaign over Koto Tabang (100.32° E, 0.20° S), Indonesia, are presented. Characteristics of gravity waves in terms of dominant wave frequencies at different heights and their vertical wavelengths are shown in the lower stratosphere during a convective and non-convective period. Gravity waves with periods ~10 h and ~4–5 h were found dominant near tropopause (a region of high stability) on all days of observation. Vertical propagation of gravity waves were seen modified near heights of the three identified strong wind shears (at ~16, 20, and 25 km heights) due to wave-mean flow interaction. Between 17 and 21 km heights, meridional wind fluctuations dominated over zonal wind, whereas from 22 to 30 km heights, wave fluctuations with periods ~3–5 h and ~8–10 h in zonal wind and temperature were highly associated, suggesting zonal orientation of wave propagation. Gravity waves from tropopause region to 30 km heights were analyzed. In general, vertical wavelength of 2–5 km dominated in all the mean-removed (~ weekly mean) wind and temperature hourly profiles. Computed vertical wavelength spectra are similar, in most of the cases, to the source spectra (1–16 km height) except that of zonal wind spectra, which is broad during active convection. Interestingly, during and after convection, gravity waves with short vertical wavelength (~2 km) and short period (~2–3 h) emerged, which were confined in the close vicinity of tropopause, and were not identified on non-convective days, suggesting convection to be the source for them. Some wave features near strong wind shear (at 25 km height) were also observed with short vertical wavelengths in both convective and non-convective days, suggesting wind shear to be the sole cause of generation and seemingly not associated with deep convection below. A drop in the temperature up to ~4–5 K (after removal of diurnal component) was observed at ~16 km height near a strong wind shear (~45–55 m s<sup>−1</sup> km<sup>−1</sup>) during active period of convection

    Spectro-Polarimetric Observation of an Emerging Flux Region: Triggering Mechanism of Ellerman Bombs

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    High spatial resolution observation of an emerging flux region (EFR) was done using a vector magnetograph and a H-alpha Lyot filtergraph with Domeless Solar Telescope at Hida Observatory on October 22, 2006. In H-alpha wing images, we could see many Ellerman bombs (EBs) in the EFR. Two observation modes, slit scan and slit fixed, were performed with the vector magnetograph, along with H-alpha filtergraph. Using H-alpha wing images, we detected 12 EBs during slit scan observation period and 9 EBs during slit fixed observation period. With slit scan observation, we found that all the EBs were distributed in the area where the spatial gradient of vertical field intensity was large, which indicates the possibility of rapid topological change in magnetic field in the area of EBs. With slit fixed observation, we found that EBs were distributed in the areas of undulatory magnetic fields, both in vertical and horizontal components. This paper is the first to report the undulatory pattern in horizontal components of magnetic field, which is also evidence for emerging magnetic flux by Parker instability. These results allow us to confirm the association between EBs and emerging flux tubes. Three triggering mechanism of EBs is discussed with respect to emerging flux tubes: 9 out of 21 EBs occurred at the footpoints of emerging flux tubes, 8 out of 21 EBs occurred at the top of emerging flux tubes, and 4 out of 21 EBs occurred at unipolar region. Each case can be explained by magnetic reconnection in the low chromosphere.Comment: 30 pages, 17 figure

    Stevens-Johnson syndrome and toxic epidermal necrolysis in childhood-onset systemic lupus erythematosus patients: a multicenter study

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    Objective: To assess Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) in a large population of childhood-onset systemic lupus erythematosus (cSLE) patients. Methods: Multicenter study including 852 cSLE patients followed in Pediatric Rheumatology centers in Sao Paulo, Brazil. SJS was defined as epidermal detachment below 10% of body surface area (BSA), overlap SJS-TEN 10-30% and TEN greater than 30% of BSA. Results: SJS and TEN were observed in 5/852 (0.6%) cSLE female patients, three patients were classified as SJS and two patients were classified as overlap SJS-TENTEN was not observed. The mean duration of SJS and overlap SJS-TEN was 15 days (range 7-22) and antibio tics induced four cases. Regarding extra-cutaneous manifestations, hepatomegaly was observed in two cSLE patients, nephritis in two and neuropsychiatric involvement and conjunctivitis were observed respectively in one patient. Hematological involvement included lymphopenia in four, leucopenia in three and thrombocytopenia in two patients. The mean SLEDAI-2K score was 14.8 (range 6-30). Laboratory analysis showed low C3, C4 and/or CH50 in two patients and the presence of anti-dsDNA autoantibody in two patients. One patient had lupus anticoagulant and another one had anticardiolipin IgG. All patients were treated with steroids and four needed additional treatment such as intravenous immunoglobulin in two patients, hydroxychloroquine and azathioprine in two and intravenous cyclophosphamide in one patient. Sepsis was observed in three cSLE patients. Two patients required intensive care and death was observed in one patient. Conclusion: Our study identified SJS and overlap SJS-TEN as rare manifestations of active cSLE associated with severe multisystemic disease, with potentially lethal outcome.Conselho Nacional de Desenvolvimento Cientifico e TecnologicoFederico FoundationNucleo de Apoio a Pesquisa "Saude da Crianca e do Adolescente" of USP (NAP-CriAd)Univ Fed Sao Paulo, Pediat Rheumatol Unit, Sao Paulo, SP, BrazilUniv Sao Paulo, Pediat Rheumatol Unit, Fac Med, Sao Paulo, BrazilUniv Sao Paulo, Div Rheumatol, Fac Med, Sao Paulo, BrazilSao Paulo State Univ UNESP, Fac Med Botucatu, Pediat Rheumatol Div, Botucatu, SP, BrazilHosp Infantil Darcy Vargas, Pediat Rheumatol Unit, Sao Paulo, BrazilUniv Fed Sao Paulo, Pediat Rheumatol Unit, Sao Paulo, SP, BrazilCNPq: 303422/2015-7CNPq: 301805/2013-0CNPq: 305068/2014-8CNPq: 301479/2015CNPq: 303752/2015-7Federico FoundationNAP-CriAd-USPWeb of Scienc

    Dioxin Toxicity In Vivo Results from an Increase in the Dioxin-Independent Transcriptional Activity of the Aryl Hydrocarbon Receptor

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    The Aryl hydrocarbon receptor (Ahr) is the nuclear receptor mediating the toxicity of dioxins -widespread and persistent pollutants whose toxic effects include tumor promotion, teratogenesis, wasting syndrome and chloracne. Elimination of Ahr in mice eliminates dioxin toxicity but also produces adverse effects, some seemingly unrelated to dioxin. Thus the relationship between the toxic and dioxin-independent functions of Ahr is not clear, which hampers understanding and treatment of dioxin toxicity. Here we develop a Drosophila model to show that dioxin actually increases the in vivo dioxin-independent activity of Ahr. This hyperactivation resembles the effects caused by an increase in the amount of its dimerisation partner Ahr nuclear translocator (Arnt) and entails an increased transcriptional potency of Ahr, in addition to the previously described effect on nuclear translocation. Thus the two apparently different functions of Ahr, dioxin-mediated and dioxin-independent, are in fact two different levels (hyperactivated and basal, respectively) of a single function

    Planar shock wave generated by uniform irradiation from two overlapped partially coherent laser beams

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    Copyright 2001 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Journal of Applied Physics, 89(5), 2571-2575, 2001 and may be found at http://dx.doi.org/10.1063/1.134218

    Heat Treatment Inhibits Skeletal Muscle Atrophy of Glucocorticoid- Induced Myopathy in Rats

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    Summary The purpose of this study was to investigate the influence of heat treatment on glucocorticoid (GC)-induced myopathy. Eight-weekold Wistar rats were randomly assigned to the control, Dex, and Dex + Heat groups. Dexamethasone (2 mg/kg) was injected subcutaneously 6 days per week for 2 weeks in the Dex and Dex + Heat group. In the Dex + Heat group, heat treatment was performed by immersing hindlimbs in water at 42 °C for 60 min, once every 3 days for 2 weeks. The extensor digitorum longus muscle was extracted following 2 weeks of experimentation. In the Dex + Heat group, muscle fiber diameter, capillary/muscle fiber ratio, and level of heat shock protein 72 were significantly higher and atrogene expression levels were significantly lower than in the Dex group. Our results suggest that heat treatment inhibits the development of GC-induced myopathy by decreasing atrogene expression and increasing angiogenesis

    Surgical treatment for pulmonary metastases from esophageal carcinoma after definitive chemoradiotherapy: Experience from a single institution

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    <p>Abstract</p> <p>Background</p> <p>Surgical treatment for pulmonary metastases is known to be a safe and potentially curative procedure for various primary malignancies. However, there are few reports regarding the prognostic role of surgical treatment for pulmonary metastases from esophageal carcinoma, especially after definitive chemoradiotherapy (CRT).</p> <p>Methods</p> <p>We retrospectively reviewed 5 patients who underwent surgical treatment for pulmonary metastases from esophageal carcinoma at our institution. The primary treatment for esophageal carcinoma was definitive CRT, and a complete response (CR) was achieved in all patients.</p> <p>Results</p> <p>The surgical procedure for pulmonary metastases was wedge resection, and pathological complete resection was achieved in all 5 patients. The disease free interval after definitive CRT varied from 7 to 36 months, with a median of 19 months. There were no perioperative complications, but postoperative respiratory failure occurred in 1 patient. The postoperative hospital stay varied from 4 to 7 days, with a median of 6 days. Three patients are now alive with a good performance status (PS) and are disease free. The other 2 patients died of primary disease. The overall survival after surgical treatment varied from 20 to 90 months, with a median of 29 months.</p> <p>Conclusions</p> <p>Surgical treatment should be considered for patients with pulmonary metastases from esophageal carcinoma who previously received CRT and achieved a CR, because it provides not only a longer survival, but also a good postoperative PS for some patients.</p

    Linfoma felino de grandes grânulos. Relato de caso

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