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1.
Rev. Soc. Cardiol. Estado de Säo Paulo ; 30(2 Suppl. B): 279-279, abr-jun., 2020.
Artigo em Português | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1117702

RESUMO

INTRODUÇÃO: A reabilitação cardíaca é uma das formas de tratamento da insuficiência cardíaca, que além de melhorar a capacidade funcional e qualidade de vida, também contribui para a redução da mortalidade e reinternação. O OBJETIVO do estudo foi identificar o perfil de pacientes submetidos areabilitação precoce em serviço de urgência e emergência. MÉTODOS: Trata-se de um estudo transversal retrospectivo de 30 pacientes com insuficiência cardíaca que foram inclusos no protocolo institucional de reabilitação. O protocolo consiste em estratificação de risco, prescrição do exercício e execução do mesmo. Todos os pacientes foram estratificados em baixo, moderado e alto risco e com base nisso foi feita a prescrição do exercício. O protocolo consiste na realização de exercícios de membros superiores com ciclo ergômetro com ou sem o uso de ventilação não invasiva. RESULTADOS: As principais etiologias da insuficiência cardíaca foram isquêmicas (30%) e cardiomiopatia dilatada (30%). O perfil hemodinâmico que prevaleceu foi o perfil C (53,3%) e a classe funcional III (46,7%). A média de fração de ejeção foi de 28,8% e a estratificação de alto risco esteve presente em 90% dos casos. CONCLUSÃO: Os dados deste estudo demonstram um predomínio de classificação de alto risco dos pacientes, assim como um tempo de internação prolongado. Assim, mais estudos na área são necessários para entendimento dessa população e para a aplicação de reabilitação cardíaca. Descritores: Insuficiência cardíaca; prevalência; exercício; fisioterapia.


Assuntos
Perfil de Saúde , Emergências , Insuficiência Cardíaca
2.
Phys Rev E ; 99(1-1): 012605, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30780382

RESUMO

We generalize the particle-conserving dynamics method of de las Heras et al. [J. Phys.: Condens. Matter 28, 244024 (2016)JCOMEL0953-898410.1088/0953-8984/28/24/244024] to binary mixtures and apply this to hard rods in one dimension. Considering the case of one species consisting of only one particle enables us to address the tagged-particle dynamics. The time-evolution of the species-labeled density profiles is compared to exact Brownian dynamics and (grand-canonical) dynamical density functional theory. The particle-conserving dynamics yields improved results over the dynamical density functional theory and well reproduces the simulation data at short and intermediate times. However, the neglect of a strict particle order (due to the fundamental statistical assumption of ergodicity) leads to errors at long times for our one-dimensional setup. The isolated study of that error makes clear the fundamental limitations of (adiabatic) density-based theoretical approaches when applied to systems of any dimension for which particle caging is a dominant physical mechanism.

3.
J Synchrotron Radiat ; 25(Pt 6): 1664-1672, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30407176

RESUMO

Since the properties of functional materials are highly dependent on their specific structure, and since the structural changes, for example during crystallization, induced by coating and annealing processes are significant, the study of structure and its formation is of interest for fundamental and applied science. However, structure analysis is often limited to ex situ determination of final states due to the lack of specialized sample cells that enable real-time investigations. The lack of such cells is mainly due to their fairly complex design and geometrical restrictions defined by the beamline setups. To overcome this obstacle, an advanced sample cell has been designed and constructed; it combines automated doctor blading, solvent vapor annealing and sample hydration with real-time grazing-incidence wide- and small-angle scattering (GIWAXS/GISAXS) and X-ray reflectivity (XRR). The sample cell has limited spatial requirements and is therefore widely usable at beamlines and laboratory-scale instruments. The cell is fully automatized and remains portable, including the necessary electronics. In addition, the cell can be used by interested scientists in cooperation with the Institute for Crystallography and Structural Physics and is expandable with regard to optical secondary probes. Exemplary research studies are presented, in the form of coating of P3HT:PC61PM thin films, solvent vapor annealing of DRCN5T:PC71BM thin films, and hydration of supported phospholipid multilayers, to demonstrate the capabilities of the in situ cell.

4.
Rev Sci Instrum ; 89(10): 10C120, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399673

RESUMO

The new C-2W Thomson scattering (TS) diagnostic consists of two individual subsystems for monitoring electron temperature (Te) and density (ne): one system in the central region is currently operational, and the second system is being commissioned to monitor the open field line region. Validating the performance of the TS's custom designed system components and unique calibration of the detection system and diagnostic as a whole is crucial to obtaining high precision Te and ne profiles of C-2W's plasma. The major components include a diode-pumped Nd:YAG laser which produces 35 pulses at up to 20 kHz, uniquely designed collection lenses with a fast numerical aperture, and uniquely designed polychromators with filters sets to optimize a Te ranging from 10 eV to 2 keV. This paper describes the design principles and techniques used to characterize the main components of the TS diagnostic on C-2W, as well as the results of Rayleigh scattering calibrations performed for the whole system response.

5.
Rev Sci Instrum ; 89(10): 10K114, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399699

RESUMO

The new C-2W experiment (also called Norman) at TAE Technologies, Inc. studies the evolution of field-reversed configuration (FRC) plasmas sustained by neutral beam injection. Data on the FRC plasma performance are provided by a comprehensive suite of diagnostics that includes over 700 magnetic sensors, four interferometer systems, multi-chord far-infrared polarimetry, two Thomson scattering systems, ten types of spectroscopic measurements, multiple fast imaging cameras with selectable atomic line filters, bolometry, reflectometry, neutral particle analyzers, and fusion product detectors. Most of these diagnostic systems are newly built using experience and data from the preceding C-2U experiment to guide the design process. A variety of commercial and custom acquisition electronics collect over 4000 raw signals from the C-2W diagnostics. These data are processed into physics results using a large-scale database of diagnostics metadata and analysis software, both built using open-source software tools.

6.
Rev Sci Instrum ; 89(10): 10C118, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399708

RESUMO

TAE Technologies' newly constructed C-2W experiment aims to improve the ion and electron temperatures in a sustained field-reversed configuration plasma. A suite of Thomson scattering systems has been designed and constructed for electron temperature and density profile measurements. The systems are designed for electron densities of 1 × 1012 cm-3 to 2 × 1014 cm-3 and temperature ranges from 10 eV to 2 keV. The central system will provide profile measurements of Te and ne at 16 radial locations from r = -9 cm to r = 64 cm with a temporal resolution of 20 kHz for 4 pulses or 1 kHz for 30 pulses. The jet system will provide profile measurements of Te and ne at 5 radial locations in the open field region from r = -5 cm to r = 15 cm with a temporal resolution of 100 Hz. The central system and its components have been characterized, calibrated, installed, and commissioned. A maximum-likelihood algorithm has been applied for data processing and analysis.

7.
Internist (Berl) ; 59(10): 1106-1113, 2018 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-30046890

RESUMO

The examination of peripheral blood smears is not only essential for the differential diagnostics of hematological diseases but can also provide important indications for general internal diseases, infections, hereditary diseases and poisoning. By the systematic analysis of a blood smear for alterations to thrombocytes, erythrocytes and leukocytes, a blood smear investigation can make a decisive contribution to the formulation of a diagnosis. In this way evidence of rare diseases can also be gained when taking the corresponding clinical findings into consideration.


Assuntos
Doenças Hematológicas , Anomalia de Pelger-Huët , Doenças Raras/sangue , Diagnóstico Diferencial , Eritrócitos , Humanos
8.
Rev Sci Instrum ; 87(11): 11D602, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910634

RESUMO

The C-2/C-2U Thomson scattering system has been substantially upgraded during the latter phase of C-2/C-2U program. A Rayleigh channel has been added to each of the three polychromators of the C-2/C-2U Thomson scattering system. Onsite spectral calibration has been applied to avoid the issue of different channel responses at different spots on the photomultiplier tube surface. With the added Rayleigh channel, the absolute intensity response of the system is calibrated with Rayleigh scattering in argon gas from 0.1 to 4 Torr, where the Rayleigh scattering signal is comparable to the Thomson scattering signal at electron densities from 1 × 1013 to 4 × 1014 cm-3. A new signal processing algorithm, using a maximum likelihood method and including detailed analysis of different noise contributions within the system, has been developed to obtain electron temperature and density profiles. The system setup, spectral and intensity calibration procedure and its outcome, data analysis, and the results of electron temperature/density profile measurements will be presented.

9.
Rev Sci Instrum ; 87(11): 11E514, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910412

RESUMO

A dual wavelength imaging system has been developed and installed on C-2U to capture 2D images of a He jet in the Scrape-Off Layer (SOL) of an advanced beam-driven Field-Reversed Configuration (FRC) plasma. The system was designed to optically split two identical images and pass them through 1 nm FWHM filters. Dual wavelength images are focused adjacent on a large format CCD chip and recorded simultaneously with a time resolution down to 10 µs using a gated micro-channel plate. The relatively compact optical system images a 10 cm plasma region with a spatial resolution of 0.2 cm and can be used in a harsh environment with high electro-magnetic noise and high magnetic field. The dual wavelength imaging system provides 2D images of either electron density or temperature by observing spectral line pairs emitted by He jet atoms in the SOL. A large field of view, combined with good space and time resolution of the imaging system, allows visualization of macro-flows in the SOL. First 2D images of the electron density and temperature observed in the SOL of the C-2U FRC are presented.

10.
Nanoscale ; 8(47): 19882-19893, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27878180

RESUMO

The functionality of compact nanostructured thin films depends critically on the degree of order and hence on the underlying ordering mechanisms during film formation. For dip coating of rigid nanorods the counteracting mechanisms, evaporation-induced self-assembly (EISA) and shear-induced alignment (SIA) have recently been identified as competing ordering mechanisms. Here, we show how to achieve highly ordered and homogeneous thin films by controlling EISA and SIA in dip coating. Therefore we identify the influences of the process parameters including temperature, initial volume fraction and nanorod aspect ratio on evaporation-induced convective flow and externally applied shear forces and evaluate the resulting films. The impact of evaporation and shear can be distinguished by analysing film thickness, surface order and bulk order by careful in situ SAXS, Raman and SEM-based image analysis. For the first time we derive processing guidelines for the controlled application of EISA and SIA towards highly ordered thin nematic films.

11.
J Phys Chem B ; 120(24): 5505-12, 2016 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-27231751

RESUMO

The structure of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC)-stabilized colloidal tetracosane emulsions was investigated by photon correlation spectroscopy and small-angle X-ray and neutron scattering, using emulsions with different neutron scattering contrasts. Special emphasis was placed on the structure of the DMPC stabilizer layer covering the emulsion droplets. A monolayer, structurally similar to a half DMPC bilayer, with a thickness of 16 Å is found. Thereby, the phosphocholine headgroups arrange flat at the oil-water interface. A deep penetration of the tetracosane oil into the stabilizer layer can be ruled out.

12.
J Phys Chem B ; 120(24): 5513-26, 2016 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-27232983

RESUMO

Using photon correlation spectroscopy, transmission electron microscopy, microcalorimetry, wide-angle X-ray scattering (WAXS), and small-angle X-ray and neutron scattering (SAXS, SANS), the structure of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC)-stabilized colloidal tetracosane suspensions was studied from the molecular level to the microscopic scale as a function of the temperature. The platelike nanocrystals exhibit for tetracosane an unusual orthorhombic low-temperature crystal structure. The corresponding WAXS pattern can be reproduced with a predicted orthorhombic unit cell (space group Pca21), which usually occurs only for much longer even-numbered n-alkanes. Special emphasis was placed on the structure of the DMPC stabilizer layer covering the nanocrystals. Their structure was investigated by SAXS and SANS, using suspensions with different neutron scattering contrasts. As for the emulsions in Part I , the crystallized nanoparticles are covered by a DMPC monolayer. Their significant smaller thickness of 10.5 Å (for the emulsions in Part I : 16 Å) could be related to a more tilted orientation of the DMPC molecules to cover the expanded surface of the crystallized nanoparticles.

13.
Langmuir ; 31(37): 10130-6, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26327573

RESUMO

ZnO nanoparticles (NPs) have great potential for their use in, e.g., thin film solar cells due to their electro-optical properties adjustable on the nanoscale. Therefore, the production of well-defined NPs is of major interest. For a targeted production process, the knowledge of the stabilization layer of the NPs during and after their formation is of particular importance. For the study of the stabilizer layer of ZnO NPs prepared in a wet chemical synthesis from zinc acetate, only ex situ studies have been performed so far. An acetate layer bound to the surface of the dried NPs was found; however, an in situ study which addresses the stabilizing layer surrounding the NPs in a native dispersion was missing. By the combination of small angle scattering with neutrons and X-rays (SANS and SAXS) for the same sample, we are now able to observe the acetate shell in situ for the first time. In addition, the changes of this shell could be followed during the ripening process for different temperatures. With increasing size of the ZnO core (d(core)) the surrounding shell (d(shell)) becomes larger, and the acetate concentration within the shell is reduced. For all samples, the shell thickness was found to be larger than the maximum extension of an acetate molecule with acetate concentrations within the shell below 50 vol %. Thus, there is not a monolayer of acetate molecules that covers the NPs but rather a swollen shell of acetate ions. This shell is assumed to hinder the growth of the NPs to larger macrostructures. In addition, we found that the partition coefficient µ between acetate in the shell surrounding the NPs and the total amount of acetate in the solution is about 10% which is in good agreement with ex situ data determined by thermogravimetric analysis.

18.
Appl Opt ; 50(8): 1136-57, 2011 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-21394186

RESUMO

The National Ignition Facility (NIF) is the world's largest optical instrument, comprising 192 37 cm square beams, each generating up to 9.6 kJ of 351 nm laser light in a 20 ns beam precisely tailored in time and spectrum. The Facility houses a massive (10 m diameter) target chamber within which the beams converge onto an ∼1 cm size target for the purpose of creating the conditions needed for deuterium/tritium nuclear fusion in a laboratory setting. A formidable challenge was building NIF to the precise requirements for beam propagation, commissioning the beam lines, and engineering systems to reliably and safely align 192 beams within the confines of a multihour shot cycle. Designing the facility to minimize drift and vibration, placing the optical components in their design locations, commissioning beam alignment, and performing precise system alignment are the key alignment accomplishments over the decade of work described herein. The design and positioning phases placed more than 3000 large (2.5 m×2 m×1 m) line-replaceable optics assemblies to within ±1 mm of design requirement. The commissioning and alignment phases validated clear apertures (no clipping) for all beam lines, and demonstrated automated laser alignment within 10 min and alignment to target chamber center within 44 min. Pointing validation system shots to flat gold-plated x-ray emitting targets showed NIF met its design requirement of ±50 µm rms beam pointing to target chamber. Finally, this paper describes the major alignment challenges faced by the NIF Project from inception to present, and how these challenges were met and solved by the NIF design and commissioning teams.

19.
Nuklearmedizin ; 49(5): 173-82, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20664888

RESUMO

PURPOSE: to evaluate the mean effective radiation dose of 13N-ammonia PET/CT and ECG-pulsing CT angiography (CTA) in the evaluation of myocardial perfusion, myocardial blood flow (MBF) and coronary morphology for the identification of subclinical CAD. PATIENTS, MATERIAL, METHODS: following rest-stress 13N-ammonia PET/CT perfusion imaging and MBF quantification, ECG-pulsing CTA at a pulse window of 70% of the R-R cycle was performed in ten healthy controls and in sixteen individuals with cardiovascular risk factors. Individual radiation dose exposure for ECG-pulsing CTA was estimated from the dose-length product. RESULTS: PET demonstrated normal perfusion in all study individuals, while hyperemic MBFs during dipyridamole stimulation and the myocardial flow reserve (MFR) in cardiovascular risk individuals were significantly lower than in healthy controls (1.34±0.26 vs. 2.28±0.47 ml/g/min and 1.48±0.39 vs. 3.24±0.81, both p≤0.0001). Further, ECG-pulsing CTA identified mild calcified and non-calcified coronary plaque burden in 7 (43%) individuals of the cardiovascular risk group. Rest-stress 13N-ammonia PET/CT perfusion study yielded a mean effective radiation dose of 3.07±0.06 mSv (2.07±0.06 mSv from the rest-stress 13N-ammonia injections and 1.0 mSv from the 2 CT transmission scans), while ECG-pulsing CTA was associated with 5.57±2.00 mSv. The mean effective radiation dose of the combined 13N-ammonia PET/CT and ECG-pulsing CTA exams in the evaluation of myocardial perfusion and coronary morphology was 8.0±1.5 mSv. CONCLUSION: 13N-ammonia PET/CT and ECG-pulsing CTA affords cardiac hybrid imaging studies in the evaluation of subclinical CAD with a relatively low mean effective radiation exposure of 8.0±1.5mSv.


Assuntos
Angiografia Coronária/métodos , Reperfusão Miocárdica/métodos , Adulto , Idoso , Amônia , Velocidade do Fluxo Sanguíneo , Circulação Coronária , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radioisótopos de Nitrogênio , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada Espiral/métodos , Tomografia Computadorizada por Raios X/métodos
20.
Artigo em Inglês | MEDLINE | ID: mdl-18003003

RESUMO

Cardiovascular magnetic resonance has been shown to provide high data quality for myocardial perfusion assessment. However, to analyze the perfusion data, some signal processing and modeling is needed to correct for motion related artifacts and limited spatial resolution. This study describes a method based on system identification, allowing, after a first step of image registration, to integrate and correct the partial volume effect in the myocardium perfusion quantification. This method is then applied to patients with coronary artery disease or hypertrophic obstructive cardiomyopathy.


Assuntos
Cardiomiopatia Hipertrófica/fisiopatologia , Doença da Artéria Coronariana/fisiopatologia , Circulação Coronária , Coração/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Modelos Cardiovasculares , Idoso , Cardiomiopatia Hipertrófica/patologia , Doença da Artéria Coronariana/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Perfusão , Radiografia
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