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1.
Nature ; 600(7890): 621-624, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34937892

RESUMO

Magnetars are strongly magnetized, isolated neutron stars1-3 with magnetic fields up to around 1015 gauss, luminosities of approximately 1031-1036 ergs per second and rotation periods of about 0.3-12.0 s. Very energetic giant flares from galactic magnetars (peak luminosities of 1044-1047 ergs per second, lasting approximately 0.1 s) have been detected in hard X-rays and soft γ-rays4, and only one has been detected from outside our galaxy5. During such giant flares, quasi-periodic oscillations (QPOs) with low (less than 150 hertz) and high (greater than 500 hertz) frequencies have been observed6-9, but their statistical significance has been questioned10. High-frequency QPOs have been seen only during the tail phase of the flare9. Here we report the observation of two broad QPOs at approximately 2,132 hertz and 4,250 hertz in the main peak of a giant γ-ray flare11 in the direction of the NGC 253 galaxy12-17, disappearing after 3.5 milliseconds. The flare was detected on 15 April 2020 by the Atmosphere-Space Interactions Monitor instrument18,19 aboard the International Space Station, which was the only instrument that recorded the main burst phase (0.8-3.2 milliseconds) in the full energy range (50 × 103 to 40 × 106 electronvolts) without suffering from saturation effects such as deadtime and pile-up. Along with sudden spectral variations, these extremely high-frequency oscillations in the burst peak are a crucial component that will aid our understanding of magnetar giant flares.


Assuntos
Astros Celestes , Atmosfera
2.
Sci Rep ; 9(1): 13864, 2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31554876

RESUMO

Nitrogen budgets help explain the supply pattern of N from the soil to the crop. Through budgeting, an improvement of the N fertilization strategy can be achieved. The objective of the present study, which was carried out under humid Mediterranean climate conditions, was to assess the influence of N fertilization, temperature and soil humidity on soil N dynamics during a whole oilseed rape growing cycle. A field experiment was conducted with two treatments: without N (0 N) and with application of 180 kg N ha-1(180 N). Mineralization was calculated from N balances made throughout the growing cycle, all while taking into account measured N uptake by oilseed rape and N losses by leaching and N2O emissions. Nitrogen net mineralization was negative after fertilization, reaching -6.73 kg N ha-1, day-1, but total net mineralization over the year was similar for the 0 N and 180 N treatments (21 and 8 kg N ha-1, respectively). Temperatures over 5 °C were sufficient for initiating the mineralization processes. In the summer, when the soil water content was below the wilting point, immobilization took place; however, there is a risk of N leaching if rainfall occurs thereafter, mainly in the 180 N treatment.


Assuntos
Brassica napus/metabolismo , Nitrogênio/metabolismo , Brassica napus/crescimento & desenvolvimento , Clima , Umidade , Nitrogênio/análise , Solo/química , Temperatura
5.
Geriátrika (Madr.) ; 21(3): 113-116, mar. 2005. tab
Artigo em Es | IBECS | ID: ibc-040054

RESUMO

Presentamos el caso de una anciana con unepisodio grave de delirium a propósito de unaimportante infección urinaria.La clínica del proceso y la sintomatología abigarradanos indican la importancia de la valoraciónintegral en el mayor, especialmente cuandola semiología de la enfermedad es típicamentegeriátrica.Describimos el cuadro sindrómico, la actuacióny el diagnostico precoz para resolver la patología


We present the case of an elder sick personwith a serious episode of delirium concerning animportant urinary infectionThe clinic of the process and the motley symptomatologyindicate us the importance of the integralvaluation in the adult, especially when thesemiology of the illness is typically geriatricWe describe the sindromic square, the performanceand the precocious diagnosis to solve thepathology


Assuntos
Feminino , Idoso , Humanos , Delírio/etiologia , Infecções Urinárias/complicações , Delírio/diagnóstico , Anamnese/métodos , Diagnóstico Diferencial
7.
Histol Histopathol ; 7(3): 321-8, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1504450

RESUMO

The bronchial-associated lymphoid tissue (BALT) is a lymphoepithelial organ, related to the immune defence of the lung and to alveolar clearance, which changes size in certain states of disease. Changes in the size of BALT were quantified and compared, and Spearman's test was used to test the relation with the bronchial epithelium. A total of 180 rats were used, divided into 6 groups of 30 as follows: 1) untreated controls; 2) exposed to cigarette smoke for two months; 3) treated with anti-pulmonary serum three doses daily over five days; 4) exposed to cigarette smoke and treated with anti-pulmonary serum; 5) sensitized with bovine albumin and exposed to an environment containing this antigen for two months; 6) exposed to cigarette smoke and bovine albumin. The lungs were processed for histological study, and were stained with the PAS-Alcian blue method. The main left bronchi BALT was studied, and the following were quantified: Lymphatic area (LA), as a percentage of the lung surface occupied by BALT; the flat epithelium (FEp), as the length of bronchial epithelium anatomically related to LA, whose cells tend to adopt a flat shape; the Contact epithelium (Cep), as the length of bronchial epithelium which is in direct contact with the LA. A percentage count of bronchial cells was made in the following classifications: globet cells; globet cells stained with the PAS-Alcian blue method; flat cells; lymphoepithelium cells; columnar cells; and bronchial epithelium cells excluding the above two cell types.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Brônquios/patologia , Tecido Linfoide/patologia , Fumar/patologia , Albuminas/imunologia , Animais , Anticorpos/administração & dosagem , Antígenos/administração & dosagem , Brônquios/imunologia , Epitélio/patologia , Feminino , Tecido Linfoide/imunologia , Masculino , Ratos , Ratos Endogâmicos
8.
Rev. costarric. cienc. méd ; 13(1/2): 9-15, mar.-jun. 1992.
Artigo em Espanhol | LILACS | ID: lil-113386

RESUMO

Se estudió la resistencia de los quistes de Lamblia intestinalis a distintas condiciones. La viabilidad de los quistes fue mayor a temperaturas bajas; a 10 C los quistes permanecieron viables por 40 días. A pH7 cincuenta por ciento de los quistes permanecieron viables hasta por 22 días. Concentraciones de kilol de 5% al 0,05% fueron 100% efectivas en los quistes de L. intestinalis. Se discute la importancia epidemiológica de estos hallazgos


Assuntos
Humanos , Cistos/etiologia , Giardia/análise , Costa Rica
9.
Histol Histopathol ; 6(4): 535-47, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1804432

RESUMO

Two groups of rats with experimental alveolitis were exposed to cigarette smoke. After comparing the results, the possible muffling effect of the cigarette smoke related to interstitial lung disease was discussed. 180 rats were divided into 6 groups of 30 animals each: Group 1: untreated controls; Group 2: exposed to cigarette smoke for 2 months; Group 3: sensitized with bovine albumin (BA) and exposed to an atmosphere with this antigen for two months, to reproduce a type of extrinsic allergic alveolitis (EAA); Group 4: treated with a single daily dose of anti-lung serum for three days followed by two days without treatment, to reproduce a type of Goodpasture's syndrome; Group 5: exposed to cigarette smoke and to BA; Group 6: exposed to cigarette smoke and treated with anti-lung serum. The animals were sacrificed and their lungs were treated for: Bronchoalveolar lavage (BAL), percentage lymphocyte count, polymorphonuclear (PMN) and alveolar macrophages (AM); semiquantitative and morphometric histological study. The semiquantitative study determined the area of the studied lung incision, affected by granulomae, increased alveolar aerial spaces, thickened alveolar walls and haemosiderine lung area. The morphometric study, based on the linear integration method, evaluated: the distance between two alveolar walls, the amount of interstice per field; and the number of AM with haemosiderine per field was counted. From the results we point out that the treated animals had significantly higher lymphocyte and BAL PMN counts than the untreated ones; no significant differences were found between the singly and doubly treated animals. The animals exposed to cigarette smoke and treated with anti-lung serum were those that showed the least number of lymphocytes and PMN of all the treated animals. The semiquantitative variables studied were all increased in comparison to the control group, most of the increases being significant. The morphometric variables revealed significant differences with respect to the untreated group, except for the animals which were treated with anti-lung serum and cigarette smoke, which showed a minimum decrease in the alveolar size and a slight increase of the interstitial tissue. Only one morphometric variable showed a significant difference between the group treated with anti-lung serum and the one treated with anti-lung serum and cigarette smoke: the number of AM with haemosiderine in the lung.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Alveolite Alérgica Extrínseca/etiologia , Doença Antimembrana Basal Glomerular/etiologia , Alvéolos Pulmonares/patologia , Fumar/efeitos adversos , Alveolite Alérgica Extrínseca/patologia , Animais , Doença Antimembrana Basal Glomerular/patologia , Anticorpos/imunologia , Líquido da Lavagem Broncoalveolar/citologia , Feminino , Granuloma/patologia , Soros Imunes/administração & dosagem , Pulmão/imunologia , Macrófagos Alveolares/patologia , Masculino , Ratos , Ratos Endogâmicos , Soroalbumina Bovina/administração & dosagem
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