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Search Results: 1 - 10 of 6320 matches for " Rodolfo; Santana "
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Magnetic Fields In Relativistic Collisionless Shocks
Rodolfo Santana,Rodolfo Barniol Duran,Pawan Kumar
Physics , 2013, DOI: 10.1088/0004-637X/785/1/29
Abstract: We present a systematic study on magnetic fields in Gamma-Ray Burst (GRB) external forward shocks (FSs). There are 60 (35) GRBs in our X-ray (optical) sample, mostly from Swift. We use two methods to study epsilon_B (fraction of energy in magnetic field in the FS). 1. For the X-ray sample, we use the constraint that the observed flux at the end of the steep decline is $\ge$ the X-ray FS flux. 2. For the optical sample, we use the condition that the observed flux arises from the FS (optical sample light curves decline as ~t^-1, as expected for the FS). Making a reasonable assumption on E (jet isotropic equivalent kinetic energy), we converted these conditions into an upper limit (measurement) on epsilon_B n^{2/(p+1)} for our X-ray (optical) sample, where n is the circumburst density and p is the electron index. Taking n=1 cm^-3, the distribution of epsilon_B measurements (upper limits) for our optical (X-ray) sample has a range of ~10^-8 -10^-3 (~10^-6 -10^-3) and median of ~few x 10^-5 (~few x 10^-5). To characterize how much amplification is needed, beyond shock compression of a seed magnetic field ~10 muG, we expressed our results in terms of an amplification factor, AF, which is very weakly dependent on n (AF propto n^0.21 ). The range of AF measurements (upper limits) for our optical (X-ray) sample is ~ 1-1000 (~10-300) with a median of ~50 (~50). These results suggest that some amplification, in addition to shock compression, is needed to explain the afterglow observations.
Costos del tratamiento por enfermedades en ni?os privados de la lactancia materna exclusiva
Figueredo Santana,Efraín; García Roldán,Rodolfo;
Revista Cubana de Medicina General Integral , 1997,
Abstract: a descriptiver and cross-sectional study on the cost of treatment diferent affections in children aged 0-4 months, who were deprived of exclusive breastfeeding, most of them before being 3 months, is conducted. there was a predominance of the respiratory and gastroiontestinal affections that caused the highest intrahospital cost due mainly to the stay. it is recommended the use of affective-participative techinique to attain an exclusive breastfeeding up to 4 months as a minimun, and to conduct studies using controls that allow to evaluate the cost-benefit and the advanteges it offers to give a planned attention to these children, and to exploit to a great extent the domestic incomes.
Costos del tratamiento por enfermedades en ni os privados de la lactancia materna exclusiva
Efraín Figueredo Santana,Rodolfo García Roldán
Revista Cubana de Medicina General Integral , 1997,
Abstract: Se realizó un estudio descriptivo y transversal en el que se tuvieron en cuenta los costos del tratamiento por diversas afecciones en ni os de 0 a 4 meses de edad que dejaron de recibir lactancia materna exclusiva, en su mayoría antes de cumplir los 3 meses. Hubo predominio de las afecciones respiratorias y gastrointestinales, las que ocasionaron el mayor costo intrahospitalario, a expensas fundamentalmente de la estadía. Se recomienda la utilización de técnicas afectivo-participativas para lograr una lactancia materna exclusiva como mínimo hasta los 4 meses, así como realizar estudios en los que se utilicen controles que permitan evaluar el costo-beneficio y las ventajas que ésta proporciona para organizar la atención a estos ni os de forma planificada, para explotar en mayor medida los ingresos domiciliarios. A descriptiver and cross-sectional study on the cost of treatment diferent affections in children aged 0-4 months, who were deprived of exclusive breastfeeding, most of them before being 3 months, is conducted. There was a predominance of the respiratory and gastroiontestinal affections that caused the highest intrahospital cost due mainly to the stay. It is recommended the use of affective-participative techinique to attain an exclusive breastfeeding up to 4 months as a minimun, and to conduct studies using controls that allow to evaluate the cost-benefit and the advanteges it offers to give a planned attention to these children, and to exploit to a great extent the domestic incomes.
Monte Carlo Simulations of the Photospheric Process
Rodolfo Santana,Patrick Crumley,Roberto A. Hernandez,Pawan Kumar
Physics , 2015,
Abstract: We present a Monte Carlo (MC) code we wrote to simulate the photospheric process and to study the photospheric spectrum above the peak energy. Our simulations were performed with a photon to electron ratio $N_{\gamma}/N_{e} = 10^{5}$, as determined by observations of the GRB prompt emission. We searched an exhaustive parameter space to determine if the photospheric process can match the observed high-energy spectrum of the prompt emission. If we do not consider electron re-heating, we determined that the best conditions to produce the observed high-energy spectrum are low photon temperatures and high optical depths. However, for these simulations, the spectrum peaks at an energy below 300 keV by a factor $\sim 10$. For the cases we consider with higher photon temperatures and lower optical depths, we demonstrate that additional energy in the electrons is required to produce a power-law spectrum above the peak-energy. By considering electron re-heating near the photosphere, the spectrum for these simulations have a peak-energy $\sim \mbox{300 keV}$ and a power-law spectrum extending to at least 10 MeV with a spectral index consistent with the prompt emission observations. We also performed simulations for different values of $N_{\gamma}/N_{e}$ and determined that the simulation results are very sensitive to $N_{\gamma}/N_{e}$. Lastly, in addition to Comptonizing a Blackbody spectrum, we also simulate the Comptonization of a $f_{\nu} \propto \nu^{-1/2}$ fast cooled synchrotron spectrum. The spectrum for these simulations peaks at $\sim 10^{4} \mbox{ keV}$, with a flat spectrum $f_{\nu} \propto \nu^{0}$ below the peak energy.
Characterization of Dairy Slurry in Sourthern Chile Farms
Salazar,Francisco; Dumont,Juan Carlos; Chadwick,David; Salda?a,Rodolfo; Santana,Mabel;
Agricultura Técnica , 2007, DOI: 10.4067/S0365-28072007000200005
Abstract: in this study 50 slurry samples were collected from commercial dairy farms located in the south of chile during 1995-1997. samples were analyzed for dry matter, ph, organic matter, available and total macro nutrients (nitrogen, phosphorus, potassium, calcium, magnesium and sodium), available and total micro nutrients (zinc, iron, manganese and copper) and total aluminum. results showed that the dry matter content in dairy effluents was low, with 62% of the samples being < 4% dm. this reflected the large volumes of water that the storage received. a great variation in nutrient content was observed in the analyzed samples, probably reflecting differences in feeding regimes, use of wash water, rainfall and age of slurry at the time of sampling. in general, the concentration of macro and micronutrients was low. in the present study, the dry matter in the slurry proved to be a good indicator of some nutrients in the samples analyzed. positive correlations (p < 0.001) were obtained between dry matter content and total phosphorus (r2 = 89%), total calcium (r2 = 87%), total magnesium (r2 = 82%), available phosphorus (r2 = 75%), ammonium nitrogen (r2 = 68%), total potassium (r2 = 64%), available potassium (r2 = 60%), total nitrogen (r2 = 55%), total zinc (r2 = 74%), total manganese (r2 = 64%) and total iron (r2 = 62%). data from this study could be used as a guideline to estimate nutrient contribution from dairy slurry when applied to farmland.
Cirurgia redutora de volume pulmonar: critérios de sele??o de pacientes no Hospital Universitário Ant?nio Pedro, Universidade Federal Fluminense, Niterói, Rio de Janeiro, RJ
Behrsin, Rodolfo Fred;Silva Junior, Cyro Teixeira da;Gabetto, José Manoel;Lima, Oriane de Almeida Santana;
Revista da Associa??o Médica Brasileira , 2003, DOI: 10.1590/S0104-42302003000300031
Abstract: background: chronic obstructive pulmonary disease (cpod) is an important problem in brazil and other countries. the clinical treatment of ambulatory patients is now reasonably standardized. lung volume reduction surgery (lvrs) is an alternative of surgical treatment of emphysema (aside from lung transplantation). objectives: the aim of this study was to analyse patient selection criteria for lvrs. methods: this study was carried out using a sample of 31 patients referred to and given assistance to at the smoking and chronic obstructive pulmonary disease outpatient ward antonio pedro hospital, who were evaluated to check whether or not they could be eligible for lvrs. aiming at evaluating the major criteria for eligibility for lvrs, the patients underwent a protocol including standardized anamnesis and physical examination, spirometry with maximum inspiratory and expiratory flow volume curves associated with post-bronchodilatator test, room air arterial blood gases, a six-minute walking test, plain chest roentgenograms and left lateral chest roentgenograms, high-resolution chest computed tomographic scans and lung perfusion scans. statistical analysis was conducted with description of data proportions. results: contraindications to surgery included chronic bronchitis (29% or nine patients), forced expiratory volume in one second (fev 1) more than 80 percent predicted (13% or four patients), negative consent for surgery (10% or three patients), fibrosis pattern, severe depression and bronchiectasis (two patients each one), solitary pulmonary nodule, severe obesity, severe bullous emphysema, pulmonary hipertension, pulmonary resection history, current cigarette smoking, diffuse emphysema with alpha-1-antitrypsin deficiency and severe cardiac disease (one patient each). indication. one selected patient with severe symptoms of emphysema met criteria for lvrs (bilateral superior lobe heterogeneous pattern of emphysema on chest computed tomography and lung perfusion scan).
Tratamiento de las fracturas diafisiarias del fémur en el ni?o
Vega Fernández,Enrique; Loredo Quesada,Tamara; Tabío Fonseca,Mercedes; León Santana,Rodolfo;
Revista Cubana de Ortopedia y Traumatolog?-a , 2005,
Abstract: a descriptive study was performed in 54 patients diagnosed with diaphyseal fracture of the femur, who had been admitted to the pediatric orthopedic and trauma service of centro habana teaching pediatric hospital at different periods from december 1998 to december 2003. the most affected age group was 0-2 years with 50 % of patients. males represented 77.7 % of patients. all the fractures were unilateral closed. the most prevailing mechanism of fracture occurence was the indirect one, with 83.3 % of patients and the most frequent was free falls with 44.44 %. conservative treatment was the choice for 90.7 % of cases. average stay at hospital was 16.24 days. final results were considered as satisfactory in 94.3 % of patients.
Escroto Agudo: frecuente urgencia uro-pediátrica
Fong Aldama,Francisco J; García Sosa,Niurka; Santana Valera,Rodolfo; Toledo Martínez,Ernesto;
Revista M??dica Electr?3nica , 2011,
Abstract: objective: analyzing the patients treated for acute scrotum at the teaching pediatric provincial hospital eliseo noel caama?o, of matanzas. patients: from january 2000 to 2010, 96 patients entered the hospital with acute scrotum; 54 of them were diagnosed as testicular torsion, 26 as torsion of morgagni hydatid, 13 as acute orchiepidydimitis associated to trauma or not, and 3 of scrotal edema. results: the higher incidence was in the first decade of life. in the analyzed study the testicular torsion was the first cause, followed by the hydatid torsion. conclusions: the patients who have these two causes of acute scrotum should be objects of surgical treatment as urgent as possible.
Testículos supernumerarios: anomalía infrecuente del sistema genital. Reporte de caso
García Sosa,Niurka; Fong Aldama,Francisco J; Santana Valera,Rodolfo; Toledo Martínez,Ernesto;
Revista M??dica Electr?3nica , 2011,
Abstract: introduction: the polyorchidism is a few frequent urologic congenital anomaly defined as the presence of more than two testicles, located inside or outside the scrotum. the polyorchidism is a rare anomaly to be considered when studying scrotal masses. the doppler echography and the computerized magnetic resonance imaging give useful elements to diagnose the presence of this entity. objective: knowing the incidence of the polyorchidism, infrequent anomaly of the genital system. patients and methods. we retrospectively reviewed the cases operated in the urology service, according to the clinic documentation records of our center in the period from 1970 to 2010, with a year average of 250 cases operated, and only one patient carrying this anomaly. we made a literature review, finding only three cases in our country and less than 100 patients in the world. we report the 3rd case of polyorchidism in cuba.
Cirurgia redutora de volume pulmonar: critérios de sele o de pacientes no Hospital Universitário Ant nio Pedro, Universidade Federal Fluminense, Niterói, Rio de Janeiro, RJ
Behrsin Rodolfo Fred,Silva Junior Cyro Teixeira da,Gabetto José Manoel,Lima Oriane de Almeida Santana
Revista da Associa??o Médica Brasileira , 2003,
Abstract: O tratamento clínico da doen a pulmonar obstrutiva cr nica (DPOC) está bem padronizado por consensos nacionais e internacionais. Junto com transplante pulmonar, a cirurgia redutora de volume pulmonar (CRVP) é alternativa de tratamento cirúrgico para o enfisema. OBJETIVOS: Avaliar critérios de inclus o e exclus o para realiza o de CRVP em pacientes com DPOC. MéTODOS: Trinta e um pacientes encaminhados e acompanhados no Ambulatório Multidisciplicar de Pesquisa em DPOC e Tabagismo dos Cursos de Pós-Gradua o em Pneumologia da Universidade Federal Fluminense, submetidos a um protocolo de avalia o para sele o de candidatos à CRVP que incluiu anamnese e exame físico padronizados, espirometria com curva fluxo volume e teste com broncodilatador, gasometria arterial com paciente respirando ar ambiente, teste de caminhada por seis minutos (TC6M), radiografia convencional de tórax em póstero anterior e perfil esquerdo, tomografia computadorizada de tórax de alta resolu o (TCAR) e cintilografia pulmonar de ventila o e perfus o. Análise estatística: descritiva. RESULTADOS: Contra-indica es para CRVP: bronquite cr nica (29% ou nove pacientes), VEF 1> 80,0% do previsto (13% ou quatro pacientes), recusa em realizar a cirurgia (10% ou três pacientes), áreas de fibrose, depress o e bronquiectasias (dois pacientes cada), nódulo pulmonar solitário neoplásico, obesidade mórbida, enfisema bolhoso grave, hipertens o pulmonar, passado de ressec o pulmonar, tabagismo corrente, enfisema difuso com deficiencia de alfa-1-antitripsina e doen a cardiaca grave (um paciente cada). Um dos pacientes selecionados concordou e foi submetido à CRVP. Sua indica o foi enfisema pulmonar heterogênio com predomínio nos lobos superiores, diagnosticado pela TCAR e cintilografia pulmonar. CONCLUS ES: Bronquite cr nica representou a principal contra-indica o em 29% dos casos. Pacientes com indica o de CRVP, freqüentemente, apresentam mais de um fator mórbido a contra-indicar o seu procedimento. A maioria dos pacientes com critérios para CRVP, a recusa, com receio do procedimento ou após programas de reabilita o pulmonar. O critério mais significativo que indicou CRVP em um paciente operado foi a presen a de enfisema heterogênio bilateral nos lobos superiores.
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