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1.
J Mol Model ; 25(10): 302, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31486895

RESUMO

We analyze the influence of different groups on the intermolecular energy of aromatic homodimers and on the interaction between a single aromatic molecule and a graphene surface. The analysis is performed for benzene, phenol, catechol, and dopamine. For calculating the energies, we employ density functional theory within the local density approximation (LDA-DFT). Our results show that the lowest intermolecular energies between the aromatic molecules are related to the T-shaped configurations. This lower energy results from the quadrupole interaction. In the case of the interaction between the graphene sheet and the aromatic molecules, the lowest energy configuration is the face to face. The adsorption energy of a molecule on a graphene surface involves π - π interactions that explain the face to face arrangement. These results provide insight into the manner by which substituents can be utilized in crystal engineering, supramolecular chemistry, bioinspired materials, formation of various molecular clusters, parameterization of force fields suitable for classical simulations, and design of novel sensing, drug delivery, and filters based on graphene.

2.
Heart ; 2018 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-30181202

RESUMO

INTRODUCTION: Heart disease (HD) accounts for high morbidity and mortality in Brazil. Underserved populations often suffer long delays in diagnosis. We aimed to evaluate the feasibility of integrating screening echocardiography (echo) with remote interpretation in the established primary care system (PC) in Brazil and to assess HD prevalence. METHODS: Over 11 months, 20 healthcare workers (four physicians, four nurses, and 12 technicians) at 16 PC centres were trained on simplified handheld echo protocols. Three screening (SC) groups, including all consented patients aged 17-20, 35-40 and 60-65 years, and patients referred (RF) for clinical indications underwent focused echo. Studies were remotely interpreted through telemedicine. Significant HD was defined as moderate/severe valve disease, ventricular dysfunction/hypertrophy, pericardial effusion, wall-motion abnormalities and congenital heart disease. RESULTS: Total 1004 patients underwent echo; 299 (29.8%) in the SC group. Median age was 51±18 years, 63.9% females; 42.7% had cardiovascular symptoms. Significant HD was found in 354 (35.3%) patients (23.4% in SC vs 40.3% in RF group, p<0.001). Prevalence was higher in patients in the SC group aged >60 years (29.2%), compared with 35-40 (14.9%) and under 20 (16.5%), p=0.012. Comparing SC to RF groups, moderate/severe left ventricular dysfunction was observed in 4.1% vs 8.1%, p=0.03, mitral regurgitation in 8.9% vs 20.3%, p<0.001 and aortic stenosis in 5.4% vs 4.3%, p=0.51. CONCLUSIONS: Integration focused echo into PC is feasible in Brazil as a strategy to deliver cardiovascular care to low-resourced areas through task shifting. The burden of HD observed suggests this tool may improve early diagnosis and referral.

3.
Lung ; 196(6): 755-760, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30178313

RESUMO

PURPOSE: Tuberculosis (TB) treatment is often carried out empirically, based on clinical and radiological findings. Chest X-ray (CXR) has good sensitivity but poor specificity in TB diagnosis. Xpert MTB/RIF (Mycobacterium tuberculosis/Rifampicin) is increasingly used in many countries as the initial diagnostic test for TB. The aim of the present study was to evaluate the association of radiological findings with the Xpert MTB/RIF test in patients with suspected pulmonary TB. METHODS: Cross-sectional study in an outpatient TB clinic. Sputum AFB smear, culture, Xpert MTB/RIF, and CXR were collected in patients with suspected pulmonary TB. RESULTS: During the study period, 312 patients met the inclusion criteria and were included in the analysis. Among Xpert MTB/RIF-positive cases, the radiographic patterns were classified as typical of TB, compatible of TB, and normal in 78 (70.3%), 31 (27.9%), and 2 (1.8%) patients, respectively. CXRs were classified as typical of TB, compatible of TB, and normal in 20 (10.0%), 25 (12.4%), and 152 (75.6%) patients, respectively, in Xpert MTB/RIF-negative cases. CONCLUSIONS: We found an association between radiographic patterns and Xpert MTB/RIF results in patients with suspected pulmonary TB. These results confirm the current recommended diagnosis algorithm.

4.
J Chem Phys ; 148(22): 222804, 2018 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-29907026

RESUMO

Using molecular dynamic simulations, we show that single-layers of molybdenum disulfide (MoS2) and graphene can effectively reject ions and allow high water permeability. Solutions of water and three cations with different valencies (Na+, Zn2+, and Fe3+) were investigated in the presence of the two types of membranes, and the results indicate a high dependence of the ion rejection on the cation charge. The associative characteristic of ferric chloride leads to a high rate of ion rejection by both nanopores, while the monovalent sodium chloride induces lower rejection rates. Particularly, MoS2 shows 100% of Fe3+ rejection for all pore sizes and applied pressures. On the other hand, the water permeation does not vary with the cation valence, having dependence only with the nanopore geometric and chemical characteristics. This study helps us to understand the fluid transport through a nanoporous membrane, essential for the development of new technologies for the removal of pollutants from water.

5.
An Acad Bras Cienc ; 90(2 suppl 1): 2543-2552, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29947665

RESUMO

Recent studies have shown that diversity in race and gender is important to improve competitiveness, creativity and innovation. However, many studies have shown that the universe of science is not diverse in none of these criteria. In this work, we quantify the gender and geographic diversity in the Brazilian science. We study in detail the profile of the titular members of the most prestigious academic institution of Brazil, the Brazilian Academy of Sciences (ABC). Our analysis shows that the members of the ABC concentrates 80% in the Southeast region and that the overwhelming majority is composed by men. We show that female and male researchers have roughly the same amount of publication per year but women produce more human resources. Using the Brazilian Researchers' Fellowship databank we show that the gender and diversity both in gender and in geography decreases along the researchers' career.

6.
Phys Rev E ; 97(3-1): 033104, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29776176

RESUMO

The slip of a fluid layer in contact with a solid confining surface is investigated for different temperatures and densities using molecular dynamic simulations. We show that for an anomalous waterlike fluid the slip goes as follows: for low levels of shear, defect slip appears and is related to the particle exchange between the fluid layers; at high levels of shear, global slip occurs and is related to the homogeneous distribution of the fluid in the confining surfaces. The oscillations in the transition velocity from defect to global slip are shown to be associated with changes in the layering distribution in the anomalous fluid.

7.
Phys Rev E ; 97(2-1): 022604, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29548200

RESUMO

We investigate the structural, thermodynamic, and dynamic behavior of a two-dimensional (2D) core-corona system using Langevin dynamics simulations. The particles are modeled by employing a core-softened potential which exhibits waterlike anomalies in three dimensions. In previous studies in a quasi-2D system a new region in the pressure versus temperature phase diagram of structural anomalies was observed. Here we show that for the two-dimensional case two regions in the pressure versus temperature phase diagram with structural, density, and diffusion anomalies are observed. Our findings indicate that, while the anomalous region at lower densities is due the competition between the two length scales in the potential at higher densities, the anomalous region is related to the reentrance of the melting line.

8.
PLoS One ; 13(3): e0193988, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29518135

RESUMO

BACKGROUND: Xpert MTB/RIF is increasingly used in many countries as the initial diagnostic test for tuberculosis (TB). Few studies have evaluated the effect of Xpert on TB diagnosis under programmatic conditions in Brazil. The aim of the present study was to evaluate the impact of introduction of Xpert MTB/RIF on TB diagnosis in a city with high TB incidence in Brazil. METHODS: We included patients evaluated with conventional diagnostic tests during one year before Xpert introduction (pre-Xpert group) and patients evaluated using Xpert during one year after the test introduction (post-Xpert group). RESULTS: 620 patients met the inclusion criteria (208 in the pre-Xpert group and 412 in the post-Xpert group) and were included in the analysis. The time until TB diagnosis was shorter in post-Xpert group (0.7 day, IQR: 0.5-1.0 day) than in pre-Xpert group (2.0 days, IQR: 2.0-2.0 days) (p<0.0001). Atypical disease characteristics, such as less weight loss, fever, dyspnea, night sweats, and hemoptysis; a negative sputum smear; a negative culture, and a chest X-ray atypical of TB were more common in post-Xpert group than in pre-Xpert group (p<0.0001 for all). CONCLUSIONS: We found that the implementation of the Xpert MTB/RIF assay, under programmatic conditions, improve and facilitate TB diagnosis, especially in cases with atypical disease manifestations. These results are likely to be generalizable to settings with a similar high TB incidence.


Assuntos
Técnicas de Amplificação de Ácido Nucleico , Tuberculose Pulmonar/diagnóstico , Adulto , Antituberculosos/farmacologia , Brasil/epidemiologia , Comorbidade , Estudos Transversais , Farmacorresistência Bacteriana/genética , Feminino , Infecções por HIV/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Valor Preditivo dos Testes , Estudos Prospectivos , Rifampina/farmacologia , Sensibilidade e Especificidade , Escarro/microbiologia , Resultado do Tratamento , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/genética , População Urbana
9.
Respir Med ; 134: 12-15, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29413498

RESUMO

BACKGROUND AND OBJECTIVES: As for all tests, the diagnostic performances of Xpert MTB/RIF might be different in settings with different tuberculosis prevalence. Aim of the study is to evaluate the performances of Xpert MTB/RIF to diagnose tuberculosis in Brazil, where 407 culture-confirmed tuberculosis patients were retrospectively enrolled in Rio Grande do Sul, between 2015 and 2016. METHODS: Sensitivity, specificity, positive and negative predictive values of the test were calculated and a logistic regression analysis was performed to assess the role played by explanatory variables in the occurrence of true positive and negative diagnostic results. RESULTS: Sensitivity of Xpert MTB/RIF was 100.0%, specificity 92.8%; positive and negative predictive values were 71.4% and 100.0%, respectively. In the HIV- infected sub-group specificity was 59.3%. In the multivariate logistic regression analysis, true positivity was associated with increasing age (1.0; p-value: 0.02) while true positivity and negativity were negatively associated with alcohol abuse. CONCLUSIONS: Xpert is sensitive and specific in the Brasilian settings.


Assuntos
Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Tuberculose/diagnóstico , Adulto , Antibióticos Antituberculose/farmacologia , Brasil , Coinfecção , Farmacorresistência Bacteriana , Feminino , Infecções por HIV/complicações , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Infecções Oportunistas/complicações , Infecções Oportunistas/diagnóstico , Valor Preditivo dos Testes , Estudos Retrospectivos , Rifampina/farmacologia , Sensibilidade e Especificidade , Tuberculose/complicações
11.
Eur Heart J Cardiovasc Imaging ; 19(4): 459-460n, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29029074

RESUMO

Aims: To develop a document by Brazilian Cardiovascular Imaging Department (DIC) and the European Association of Cardiovascular Imaging (EACVI) to review and summarize the most recent evidences about the non-invasive assessment of patients with Chagas disease, with the intent to set up a framework for standardized cardiovascular imaging to assess cardiovascular morphologic and functional disturbances, as well as to guide the subsequent process of clinical decision-making. Methods and results: Chagas disease remains one of the most prevalent infectious diseases in Latin America, and has become a health problem in non-endemic countries. Dilated cardiomyopathy is the most severe manifestation of Chagas disease, which causes substantial disability and early mortality in the socially most productive population leading to a significant economical burden. Prompt and correct diagnosis of Chagas disease requires specialized clinical expertise to recognize the unique features of this disease. The appropriate and efficient use of cardiac imaging is pivotal for diagnosing the cardiac involvement in Chagas disease, to stage the disease, assess patients' prognosis and address management. Echocardiography is the most common imaging modality used to assess, and follow-up patients with Chagas disease. The presence of echocardiographic abnormalities is of utmost importance, since it allows to stage patients according to disease progression. In early stages of cardiac involvement, echocardiography may demonstrate segmental left ventricuar wall motion abnormalities, mainly in the basal segments of inferior, inferolateral walls, and the apex, which cannot be attributed to obstructive coronary artery arteries. The prevalence of segmental wall motion abnormalities varies according to the stage of the disease, reaching about 50% in patients with left ventricular dilatation and dysfunction. Speckle tracking echocardiography allows a more precise and quantitative measurement of the regional myocardial function. Since segmental wall motion abnormalities are frequent in Chagas disease, speckle tracking echocardiography may have an important clinical application in these patients, particularly in the indeterminate forms when abnormalities are more subtle. Speckle tracking echocardiography can also quantify the heterogeneity of systolic contraction, which is associated with the risk of arrhythmic events. Three-dimensional (3D) echocardiography is superior to conventional two-dimensional (2D) echocardiography for assessing more accurately the left ventricular apex and thus to detect apical aneurysms and thrombus in patients in whom ventricular foreshortening is suspected by 2D echocardiography. In addition, 3D echocardiography is more accurate than 2D Simpson s biplane rule for assessing left ventricular volumes and function in patients with significant wall motion abnormalities, including aneurysms with distorted ventricular geometry. Contrast echocardiography has the advantage to enhancement of left ventricular endocardial border, allowing for more accurate detection of ventricular aneurysms and thrombus in Chagas disease. Diastolic dysfunction is an important hallmark of Chagas disease even in its early phases. In general, left ventricular diastolic and systolic dysfunction coexist and isolated diastolic dysfunction is uncommon but may be present in patients with the indeterminate form. Right ventricular dysfunction may be detected early in the disease course, but in general, the clinical manifestations occur late at advanced stages of Chagas cardiomyopathy. Several echocardiographic parameters have been used to assess right ventricular function in Chagas disease, including qualitative evaluation, myocardial performance index, tissue Doppler imaging, tricuspid annular plane systolic excursion, and speckle tracking strain. Cardiac magnetic resonance (CMR) is useful to assess global and regional left ventricular function in patients with Chagas diseases. Myocardial fibrosis is a striking feature of Chagas cardiomyopathy and late gadolinium enhancement (LGE) is used to detect and quantify the extension of myocardial fibrosis. Myocardial fibrosis might have a role in risk stratification of patients with Chagas disease. Limited data are available regarding right ventricular function assessed by CMR in Chagas disease. Radionuclide ventriculography is used for global biventricular function assessment in patients with suspected or definite cardiac involvement in Chagas disease with suboptimal acoustic window and contraindication to CMR. Myocardial perfusion scintigraphy may improve risk stratification to define cardiac involvement in Chagas disease, especially in the patients with devices who cannot be submitted to CMR and in the clinical setting of Chagas patients whose main complaint is atypical chest pain. Detection of reversible ischemic defects predicts further deterioration of left ventricular systolic function and helps to avoid unnecessary cardiac catheterization and coronary angiography. Conclusion: Cardiac imaging is crucial to detect the cardiac involvement in patients with Chagas disease, stage the disease and stratify patient risk and address management. Unfortunately, most patients live in regions with limited access to imaging methods and point-of-care, simplified protocols, could improve the access of these remote populations to important information that could impact in the clinical management of the disease. Therefore, there are many fields for further research in cardiac imaging in Chagas disease. How to better provide an earlier diagnosis of cardiac involvement and improve patients risk stratification remains to be addressed using different images modalities.

12.
Rev. pesqui. cuid. fundam. (Online) ; 9(3): 688-695, jul.-set. 2017. tab
Artigo em Inglês, Português | LILACS | ID: biblio-982951

RESUMO

Objective: To evaluate the prescribed volume of enteral feeding versus the volume infused, identifying the diet for interruption, and expenses generated by these interruptions. Methods: Observational study with adults and elderly patients receiving enteral nutrition in a private hospital in São Paulo. Data collection was performed by means of electronic medical records. Results: The infused volume was significantly lower than the amount prescribed in the five days of monitoring in the entire sample. The main complication in the experimental diet was diarrhea. Spending on non-diet administration amount to 41.4% of the amount spent for this service. Conclusion: This study contributes to the performance and nutritionist performance in conjunction with the multidisciplinary team in Nutrition Therapy aiming at the improvement of the patient.


Objetivo: Avaliar o volume prescrito de dieta enteral versus o volume infundido, identificando as causas de interrupção da dieta e os gastos gerados por essas interrupções. Métodos: Estudo observacional, com pacientes adultos e idosos, recebendo nutrição enteral em um hospital particular de São Paulo. A coleta de dados foi realizada por meio de prontuário eletrônico. Resultados: O volume infundido foi significantemente menor que o volume prescrito, nos cinco dias de acompanhamento, em toda a amostra. A principal intercorrência na administração da dieta foi a diarreia. Os gastos com a não administração da dieta somam 41,4% do valor despendido para esse serviço. Conclusão: Este estudo contribui para a atuação e desempenho do nutricionista em conjunto com a Equipe Multidisciplinar em Terapia Nutricional visando a melhora do paciente.


Objetivo: Evaluar el volumen prescrito de la alimentación enteral en comparación con el volumen infundido, la identificación de la dieta para la interrupción y gastos generados por estas interrupciones. Métodos: Estudio observacional con pacientes adultos y ancianos que reciben nutrición enteral en un hospital privado de Sao Paulo. La recolección de datos se realizó por medio de registros médicos electrónicos. Resultados: El volumen infundido fue significativamente menor que la cantidad prescrita en los cinco días de monitoreo en toda la muestra. La complicación principal de la dieta experimental fue la diarrea. El gasto en cantidad de administración no dietética al 41,4% de la cantidad gastada por este servicio. Conclusión: Este estudio contribuye al rendimiento y desempeño en nutrición en conjunto con el equipo multidisciplinario en el tratamiento nutricional destinado a la mejora del paciente.


Assuntos
Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Nutrição Enteral , Terapia Nutricional/economia , Terapia Nutricional/métodos , Terapia Nutricional/normas , Terapia Nutricional , Brasil , Protocolos Clínicos , Equipe de Assistência ao Paciente/tendências
13.
An Acad Bras Cienc ; 89(3 Suppl): 2525-2543, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28678963

RESUMO

This article presents an analysis of Brazilian research on High Energy Physics (HEP) indexed by Web of Science (WoS) from 1983 to 2013. Scientometric indicators for output, collaboration and impact were used to characterize the field under study. The results show that the Brazilian articles account for 3% of total HEP research worldwide and that the sharp rise in the scientific activity between 2009 and 2013 may have resulted from the consolidation of graduate programs, the increase of the funding and of the international collaboration as well as the implementation of the Rede Nacional de Física de Altas Energias (RENAFAE) in 2008. Our results also indicate that the collaboration patterns in terms of the authors, the institutions and the countries confirm the presence of Brazil in multinational Big Science experiments, which may also explain the prevalence of foreign citing documents (all types), emphasizing the international prestige and visibility of the output of Brazilian scientists. We concluded that the scientometric indicators suggested scientific maturity in the Brazilian HEP community due to its long history of experimental research.

14.
Rev. pesqui. cuid. fundam. (Online) ; 9(3): 688-695, jul.-set. 2017. tab
Artigo em Inglês, Português | BDENF - Enfermagem | ID: bde-31116

RESUMO

Objective: To evaluate the prescribed volume of enteral feeding versus the volume infused, identifying the diet for interruption, and expenses generated by these interruptions. Methods: Observational study with adults and elderly patients receiving enteral nutrition in a private hospital in São Paulo. Data collection was performed by means of electronic medical records. Results: The infused volume was significantly lower than the amount prescribed in the five days of monitoring in the entire sample. The main complication in the experimental diet was diarrhea. Spending on non-diet administration amount to 41.4% of the amount spent for this service. Conclusion: This study contributes to the performance and nutritionist performance in conjunction with the multidisciplinary team in Nutrition Therapy aiming at the improvement of the patient.(AU)


Objetivo: Avaliar o volume prescrito de dieta enteral versus o volume infundido, identificando as causas de interrupção da dieta e os gastos gerados por essas interrupções. Métodos: Estudo observacional, com pacientes adultos e idosos, recebendo nutrição enteral em um hospital particular de São Paulo. A coleta de dados foi realizada por meio de prontuário eletrônico. Resultados: O volume infundido foi significantemente menor que o volume prescrito, nos cinco dias de acompanhamento, em toda a amostra. A principal intercorrência na administração da dieta foi a diarreia. Os gastos com a não administração da dieta somam 41,4% do valor despendido para esse serviço. Conclusão: Este estudo contribui para a atuação e desempenho do nutricionista em conjunto com a Equipe Multidisciplinar em Terapia Nutricional visando a melhora do paciente.(AU)


Objetivo: Evaluar el volumen prescrito de la alimentación enteral en comparación con el volumen infundido, la identificación de la dieta para la interrupción y gastos generados por estas interrupciones. Métodos: Estudio observacional con pacientes adultos y ancianos que reciben nutrición enteral en un hospital privado de Sao Paulo. La recolección de datos se realizó por medio de registros médicos electrónicos. Resultados: El volumen infundido fue significativamente menor que la cantidad prescrita en los cinco días de monitoreo en toda la muestra. La complicación principal de la dieta experimental fue la diarrea. El gasto en cantidad de administración no dietética al 41,4% de la cantidad gastada por este servicio. Conclusión: Este estudio contribuye al rendimiento y desempeño en nutrición en conjunto con el equipo multidisciplinario en el tratamiento nutricional destinado a la mejora del paciente.(AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Nutrição Enteral , Terapia Nutricional/economia , Terapia Nutricional/métodos , Terapia Nutricional/normas , Terapia Nutricional , Equipe de Assistência ao Paciente/tendências , Brasil , Protocolos Clínicos
15.
J Chem Phys ; 146(23): 234509, 2017 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-28641422

RESUMO

We performed molecular dynamics simulations of water confined within AlPO4-54 nanotubes. AlPO4-54 is an artificial material made of AlO4 and of PO4 in tetrahedra arranged in a periodic structure forming pores of approximately 1.3 nm in diameter. This makes AlPO4-54 an excellent candidate for practical applications, such as for water filtration and desalination. In this work, the structural and dynamical properties of the confined water are analyzed for various temperatures and water loadings. We find that the water structure is controlled by the heterogeneity of the nanopore surface with the water molecules located preferentially next to the surface of oxygens of AlPO4-54; consequently, at very low densities, water forms helicoidal structures in string-like arrangements.

16.
Phys Chem Chem Phys ; 19(20): 12921-12927, 2017 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-28480464

RESUMO

In this paper the transport properties of water confined inside hydrophobic and hydrophilic nanotubes are compared for different nanotube radii and densities. While for wider nanotubes the nature of the wall plays no relevant role in the water mobility, for small nanotubes the hydrophobic confinement presents a peculiar behavior. As the density is increased the viscosity shows a huge increase associated with a small increase in the diffusion coefficient. This breakdown in the Stokes-Einstein relation for diffusion and viscosity was observed in the hydrophobic, but not in the hydrophilic nanotubes. The mechanism underlying this behavior is explained in terms of the structure of water under confinement. This result indicates that some of the features observed for water inside hydrophobic carbon nanotubes cannot be observed in other nanopores.

18.
An. acad. bras. ciênc ; 89(3,supl): 2525-2543, 2017. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-886790

RESUMO

ABSTRACT This article presents an analysis of Brazilian research on High Energy Physics (HEP) indexed by Web of Science (WoS) from 1983 to 2013. Scientometric indicators for output, collaboration and impact were used to characterize the field under study. The results show that the Brazilian articles account for 3% of total HEP research worldwide and that the sharp rise in the scientific activity between 2009 and 2013 may have resulted from the consolidation of graduate programs, the increase of the funding and of the international collaboration as well as the implementation of the Rede Nacional de Física de Altas Energias (RENAFAE) in 2008. Our results also indicate that the collaboration patterns in terms of the authors, the institutions and the countries confirm the presence of Brazil in multinational Big Science experiments, which may also explain the prevalence of foreign citing documents (all types), emphasizing the international prestige and visibility of the output of Brazilian scientists. We concluded that the scientometric indicators suggested scientific maturity in the Brazilian HEP community due to its long history of experimental research.

19.
Echocardiography ; 33(9): 1326-34, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27460782

RESUMO

BACKGROUND: Pulmonary arterial hypertension (PAH) is characterized by elevated mean pulmonary arterial pressure with abnormal right ventricular (RV) pressure overload that may alter left ventricular (LV) function. The aim of this study was to assess the impact of RV pressure overload on LV function in PAH patients using two-dimensional (2D) speckle tracking strain. METHODS: The study enrolled 37 group 1 PAH patients and 38 age- and gender-matched healthy controls. LV longitudinal and radial 2D strains were measured with and without including the ventricular septum. Six-minute walk test (6MWT) and brain natriuretic peptide (BNP) levels were also obtained in patients with PAH. RESULTS: The mean age of patients was 46.4 ± 14.8 years, 76% women, and 16 patients (43%) had schistosomiasis. Sixteen patients (43%) were in WHO class III or IV under specific treatment for PAH. The overall 6MWT distance was 441 meters, and the BNP levels were 80 pg/mL. Patients with PAH more commonly presented with LV diastolic dysfunction and impairment of RV function when compared to controls. LV global longitudinal and radial strains were lower in patients than in controls (-17.9 ± 2.8 vs. -20.5 ± 1.9; P < 0.001 and 30.8 ± 10.5 vs. 49.8 ± 15.4; P < 0.001, respectively). After excluding septal values, LV longitudinal and radial strains remained lower in patients than in controls. The independent factors associated with global LV longitudinal strain were LV ejection fraction, RV fractional area change, and tricuspid annular systolic motion. CONCLUSIONS: This study showed impaired LV contractility in patients with PAH assessed by speckle tracking strain, irrespective of ventricular septal involvement. Global LV longitudinal strain was associated independently with RV fractional area change and tricuspid annular systolic motion, after adjustment for LV ejection fraction.


Assuntos
Ecocardiografia Doppler/métodos , Hipertensão Pulmonar/complicações , Hipertensão Pulmonar/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia , Adolescente , Adulto , Técnicas de Imagem por Elasticidade/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
20.
J Phys Chem B ; 120(9): 2460-70, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26890321

RESUMO

A new computational model for sodium chloride, the NaCl/ϵ, is proposed. The force field employed for the description of the NaCl is based on a set of radial particle-particle pair potentials involving Lennard-Jones (LJ) and Coulombic forces. The parametrization is obtained by fitting the density of the crystal and the density and the dielectric constant of the mixture of the salt with water at a diluted solution. Our model shows good agreement with the experimental values for the density and for the surface tension of the pure system, and for the density, the viscosity, the diffusion, and the dielectric constant for the mixture with water at various molal concentrations. The NaCl/ϵ together with the water TIP4P/ϵ models provide a good approximation for studying electrolyte solutions.

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