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1.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557886

RESUMO

JET's frequency-modulated continuous wave (FMCW) reflectometers have been operating well with the current design since 2005, and density profiles have been automatically calculated intershot since then. However, the calculated profiles had long suffered from several shortcomings: poor agreement with other diagnostics, sometimes inappropriately moving radially by several centimeters, elevated levels of radial jitter, and persistent wriggles (strong unphysical oscillations). In this research, several techniques are applied to the reflectometry data analysis, and the shortcomings are significantly improved. Starting with improving the equilibrium reconstruction that estimates the background magnetic field, adding a ripple correction in the reconstructed magnetic field profile, and adding new inner-wall reflection positions estimated through ray-tracing, these changes not only improve the agreement of reconstructed profiles to other diagnostics but also solve density profile wriggles that were present during band transitions. Other smaller but also persistent wriggles were also suppressed by applying a localized correction to the measured beat frequency where persistent oscillations are present. Finally, the burst analysis method, as introduced by Varela et al. [Nucl. Fusion 46 S693 (2006)], has been implemented to extract the beat frequency from stacked spectrograms. Due to the strong suppression of spurious reflections, the radial jitter that sometimes would span several centimeters has been strongly reduced. The stacking of spectrograms has also been shown to be very useful for stacking recurring events, like small gas puff modulations, and extracting transport coefficients that would otherwise be below the noise level.

2.
Rev Sci Instrum ; 87(11): 11E722, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910673

RESUMO

A new multichannel frequency modulated continuous-wave reflectometry diagnostic has been successfully installed and commissioned on ASDEX Upgrade to measure the plasma edge electron density profile evolution in front of the Ion Cyclotron Range of Frequencies (ICRF) antenna. The design of the new three-strap ICRF antenna integrates ten pairs (sending and receiving) of microwave reflectometry antennas. The multichannel reflectometer can use three of these to measure the edge electron density profiles up to 2 × 1019 m-3, at different poloidal locations, allowing the direct study of the local plasma layers in front of the ICRF antenna. ICRF power coupling, operational effects, and poloidal variations of the plasma density profile can be consistently studied for the first time. In this work the diagnostic hardware architecture is described and the obtained density profile measurements were used to track outer radial plasma position and plasma shape.

3.
Rev Sci Instrum ; 87(9): 093506, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27782550

RESUMO

At the tokamak Joint European Torus (JET), the electron cyclotron emission spectra in O-mode and X-mode polarisations are diagnosed simultaneous in absolute terms for several harmonics with two Martin-Puplett interferometers. From the second harmonic range in X-mode polarisation, the electron temperature profile can be deduced for the outboard side (low magnetic field strength) of JET but only for some parts of the inboard side (high magnetic field strength). This spatial restriction can be bypassed, if a cutoff is not present inside the plasma for O-mode waves in the first harmonic range. Then, from this spectral domain, the profile on the entire inboard side is accessible. The profile determination relies on the new absolute and independent calibration for both interferometers. During the calibration procedure, the antenna pattern was investigated as well, and, potentially, an increase in the diagnostic responsivity of about 5% was found for the domain 100-300 GHz. This increase and other uncertainty sources are taken into account in the thorough revision of the uncertainty for the diagnostic absolute calibration. The uncertainty deduced and the convolution inherent for Fourier spectroscopy diagnostics have implications for the temperature profile inferred. Having probed the electron cyclotron emission spectra in orthogonal polarisation directions for the first harmonic range, a condition is derived for the reflection and polarisation-scrambling coefficients of the first wall on the outboard side of JET.

4.
Phys Rev Lett ; 116(6): 065002, 2016 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-26918997

RESUMO

High spatial resolution Doppler backscattering measurements in JET have enabled new insights into the development of the edge Er. We observe fine-scale spatial structures in the edge Er well with a wave number krρi≈0.4-0.8, consistent with stationary zonal flows, the characteristics of which vary with density. The zonal flow amplitude and wavelength both decrease with local collisionality, such that the zonal flow E×B shear increases. Above the minimum of the L-H transition power threshold dependence on density, the zonal flows are present during L mode and disappear following the H-mode transition, while below the minimum they are reduced below measurable amplitude during L mode, before the L-H transition.

5.
Braz. j. med. biol. res ; 48(11): 953-964, Nov. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-762901

RESUMO

Cocos nucifera (L.) (Arecaceae) is commonly called the “coconut tree” and is the most naturally widespread fruit plant on Earth. Throughout history, humans have used medicinal plants therapeutically, and minerals, plants, and animals have traditionally been the main sources of drugs. The constituents of C. nucifera have some biological effects, such as antihelminthic, anti-inflammatory, antinociceptive, antioxidant, antifungal, antimicrobial, and antitumor activities. Our objective in the present study was to review the phytochemical profile, pharmacological activities, and toxicology of C. nucifera to guide future preclinical and clinical studies using this plant. This systematic review consisted of searches performed using scientific databases such as Scopus, Science Direct, PubMed, SciVerse, and Scientific Electronic Library Online. Some uses of the plant were partially confirmed by previous studies demonstrating analgesic, antiarthritic, antibacterial, antipyretic, antihelminthic, antidiarrheal, and hypoglycemic activities. In addition, other properties such as antihypertensive, anti-inflammatory, antimicrobial, antioxidant, cardioprotective, antiseizure, cytotoxicity, hepatoprotective, vasodilation, nephroprotective, and anti-osteoporosis effects were also reported. Because each part of C. nucifera has different constituents, the pharmacological effects of the plant vary according to the part of the plant evaluated.


Assuntos
Animais , Humanos , Anti-Infecciosos/farmacologia , Cocos/química , Fitoterapia , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Anticonvulsivantes/farmacologia , Anti-Hipertensivos/farmacologia , Osso e Ossos/efeitos dos fármacos , Cocos/toxicidade , Hipoglicemiantes/farmacologia
6.
Braz J Med Biol Res ; 48(11): 953-64, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26292222

RESUMO

Cocos nucifera (L.) (Arecaceae) is commonly called the "coconut tree" and is the most naturally widespread fruit plant on Earth. Throughout history, humans have used medicinal plants therapeutically, and minerals, plants, and animals have traditionally been the main sources of drugs. The constituents of C. nucifera have some biological effects, such as antihelminthic, anti-inflammatory, antinociceptive, antioxidant, antifungal, antimicrobial, and antitumor activities. Our objective in the present study was to review the phytochemical profile, pharmacological activities, and toxicology of C. nucifera to guide future preclinical and clinical studies using this plant. This systematic review consisted of searches performed using scientific databases such as Scopus, Science Direct, PubMed, SciVerse, and Scientific Electronic Library Online. Some uses of the plant were partially confirmed by previous studies demonstrating analgesic, antiarthritic, antibacterial, antipyretic, antihelminthic, antidiarrheal, and hypoglycemic activities. In addition, other properties such as antihypertensive, anti-inflammatory, antimicrobial, antioxidant, cardioprotective, antiseizure, cytotoxicity, hepatoprotective, vasodilation, nephroprotective, and anti-osteoporosis effects were also reported. Because each part of C. nucifera has different constituents, the pharmacological effects of the plant vary according to the part of the plant evaluated.


Assuntos
Anti-Infecciosos/farmacologia , Cocos/química , Fitoterapia , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Analgésicos/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Anticonvulsivantes/farmacologia , Anti-Hipertensivos/farmacologia , Osso e Ossos/efeitos dos fármacos , Cocos/toxicidade , Humanos , Hipoglicemiantes/farmacologia
7.
Rev Sci Instrum ; 83(10): 10E317, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23130802

RESUMO

The ASDEX Upgrade frequency modulated continuous wave broadband reflectometer system uses a mono-static antenna configuration with in-vessel hog-horns and 3 dB directional couplers. The operation of the new electron cyclotron resonance heating (ECRH) launcher and the start of collective Thomson scattering experiments caused several events where the fragile dummy loads inside the high field side directional couplers were damaged, due to excessive power resulting from the ECRH stray fields. In this paper, we present a non-conventional application of the existing three-port directional coupler that hardens the system to the ECRH stray fields and at the same time generates the necessary reference signal. Electromagnetic simulations and laboratory tests were performed to validate the proposed solution and are compared with the in-vessel calibration tests.

8.
Phlebology ; 26(4): 157-61, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21690172

RESUMO

OBJECTIVE: To evaluate phase-contrast velocity mapping (PCVM) as a diagnostic tool for pelvic congestion syndrome and comparing this approach with direct venography. METHOD: We prospectively include nine women with clinical suspicion of pelvic congestion syndrome during a six-month period. All patients underwent a magnetic resonance phase-contrast scan before a direct venography. We considered a case of pelvic congestion syndrome when the PCVM showed a retrograde or slow (less than 5 cm/second) flow in any gonadal vein. This criterion was compared with the standard diagnostic criterion observed from a direct venography. RESULTS: Using direct venography we found 14 abnormal veins and all of them were correctly identified by the PCVM. The other four veins were found to be normal by the direct venography. However, two of them (the same patient) were abnormal in the PCVM, even though this patient had the classical symptoms of pelvic congestion syndrome. CONCLUSION: PCVM is a useful tool for diagnosing pelvic contrast syndrome and can avoid invasive procedures such as direct venography.


Assuntos
Meios de Contraste/administração & dosagem , Angiografia por Ressonância Magnética , Pelve/irrigação sanguínea , Flebografia , Varizes/diagnóstico , Varizes/fisiopatologia , Adulto , Velocidade do Fluxo Sanguíneo , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Síndrome
9.
Rev Sci Instrum ; 81(10): 10D939, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21061484

RESUMO

A new system has been installed on the JET tokamak consisting of six independent fast-sweeping reflectometers covering four bands between 44 and 150 GHz and using orthogonal polarizations. It has been designed to measure density profiles from the plasma edge to the center, launching microwaves through 40 m of oversized corrugated waveguides. It has routinely produced density profiles with a maximum repetition rate of one profile every 15 µs and up to 100,000 profiles per pulse.

10.
Phys Med Biol ; 55(18): 5437-49, 2010 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-20736498

RESUMO

The response of the new radiochromic MD-V2-55 film exposed to (60)Co gamma rays has been investigated. A HP Scanjet 7650 document flatbed scanner has been used to evaluate the response. Before studying the film response, the linearity and stability of the scanner were analysed using three calibrated neutral optical filters, finding that the scanner is linear up to an optical density equal to 1 and stable over a period of more than 6 months with a variation of about approximately 0.3% on the optical density for all filters. The warm-up effect of the scanner was also evaluated and a gradual increase of about 1% in the optical density was observed during the first 15 min of successive readings. Six 1 cm(2) pieces of film per absorbed dose were irradiated to doses ranging from 0.5 to 6500 Gy. The response of the film was evaluated at various spatial resolutions using the two scanning modes (transmission versus reflection) of the scanner. The data analysis was made by extracting all three colour channels from the film image. The results show that the spatial resolution does not have an effect on the absolute optical density, but strongly affects the relative uncertainty in the absorbed dose. A linear dependence of the optical density with absorbed dose is observed if the film is read in transmission mode, while in the reflection mode the optical density is described by a second-order polynomial function. The dose dynamic range of the dosimetry system depends significantly on the method used to evaluate the response of the film (about a factor of 3 on the maximum absorbed dose limit for the green and blue colour channels). Finally, a comparison between this new and an old dosimetry system was also made by scanning MD-55-2 in a Microtek ScanMaker E3 scanner under the same conditions as with the HP scanner. It is observed that the new film produces lower uncertainty in the measurement, which means that it is more uniform. Good agreement is obtained between the optical densities measured for both films read in different scanners. The optical density is statistically the same in the useful dose region using both digitizers, which can be attributed to the use of neutral optical filters with known optical density to calibrate the scanners. Based on these results, it is suggested to use calibrated neutral filters to standardize the systems when flat bed document scanners are used to evaluate the film response.


Assuntos
Dosimetria Fotográfica/métodos , Raios gama , Calibragem , Radioisótopos de Cobalto , Doses de Radiação , Água
11.
Rev Sci Instrum ; 79(10): 10F108, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19068528

RESUMO

We present the main design options and implementation of an X-mode reflectometer developed and successfully installed at JET using an innovative approach. It aims to prove the viability of measuring density profiles with high spatial and temporal resolution using broadband reflectometry operating in long and complex transmission lines. It probes the plasma with magnetic fields between 2.4 and 3.0 T using the V band [approximately (0-1.4)x10(19) m(-3)]. The first experimental results show the high sensitivity of the diagnostic when measuring changes in the plasma density profile occurring ITER relevant regimes, such as ELMy H-modes. The successful demonstration of this concept motivated the upgrade of the JET frequency modulation of the continuous wave (FMCW) reflectometry diagnostic, to probe both the edge and core. This new system is essential to prove the viability of using the FMCW reflectometry technique to probe the plasma in next step devices, such as ITER, since they share the same waveguide complexity.

16.
Hipertensión (Madr., Ed. impr.) ; 18(7): 320-326, oct. 2001. tab
Artigo em Es | IBECS | ID: ibc-11196

RESUMO

Esta revisión provee una actualización de la información científica más reciente sobre el papel del consumo de tabaco (CT) en el desarrollo y progresión de las complicaciones crónicas en los pacientes diabéticos. El mecanismo exacto a través del cual el CT incrementa el daño microvascular y macrovascular no es completamente comprendido. Sin embargo, existe numerosa evidencia que demuestra que el CT en pacientes diabéticos está claramente asociado con la aceleración y un peor pronóstico de estas complicaciones y además hay evidencia consistente que demuestra el beneficio precoz que se obtiene con la cesación del CT en pacientes diabéticos. Por tanto en cada visita clínica el CT debe de ser valorado en todos los pacientes con diabetes mellitus y debe realizarse un esfuerzo para prevenir la iniciación de este hábito, así como ofrecer programas de ayuda al paciente diabético para que abandone el CT. Nosotros esperamos que esta revisión ponga sobre aviso al médico sobre la necesidad de incrementar tanto la frecuencia del consejo antitabaco como el tratamiento del tabaquismo en esta población (AU)


Assuntos
Humanos , Nicotiana/efeitos adversos , Nefropatias Diabéticas/etiologia , Retinopatia Diabética/etiologia , Diabetes Mellitus/fisiopatologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/mortalidade
18.
Rev Bras Enferm ; 53(3): 458-66, 2000.
Artigo em Português | MEDLINE | ID: mdl-12138428

RESUMO

The purpose of this study was to carry out an historical rescue of the institutionalization of nursing education as it occurred in Paraíba. Due to the lack of written information on this subject, the authors carried out the research relying on primary and secondary oral sources. The authors verified that the institutionalization of nursing education in Paraíba occurred in the 1950's, period in which the so-called medical-sanitary model was in vogue at public health services. Among the many significant moments of the study, the authors highlight an interview with Mrs. Doralice Kluppel, a nurse which participated in the team of teachers which established the first School of Nursing in Paraíba, for she brings out feelings of worth and respect for the work carried out by this group of forerunners in nursing education in Paraíba.


Assuntos
Educação em Enfermagem/organização & administração , Brasil
19.
Rev. estomatol. Hered ; 9(1/2): 24-7, ene.-dic. 1999. ilus, tab
Artigo em Espanhol | LILACS, LIPECS | ID: lil-263006

RESUMO

Una paciente de 19 años de edad con sindrome doloroso miofacial tratada mediante férulas miorelajantes durante cuatro años sin resultados positivos, fue transferida al área de ortodoncia. Se diagnósticó maloclusión Clase I. Antes, durante y después del tratamiento ortodóncico se realizaron registros estandarizados que incluyeron: modelos de estudio, radiografías panorámica y cefalométrica, registros, fotográficos, electromiográficos y kinesiográficos. La recuperación de las relaciones oclusales armonicas condujo a un mejoramiento de la sintomatología y la comparación de los registros pre y post tratamiento mostró cambios significativos en la actividad muscular y movimientos mandibulares excursivos. El presente caso es un ejemplo de los beneficios del tratamiento ortodóncico como alternativa en casos de disfunción de ATM y sindrome doloroso miofacial.


Assuntos
Humanos , Feminino , Adulto , Síndromes da Dor Miofascial/terapia , Eletromiografia , Síndrome da Disfunção da Articulação Temporomandibular/terapia
20.
Rom J Physiol ; 35(1-2): 169-77, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-11000877

RESUMO

Young coffee plants were treated by putting a droplet of a solution containing 10B-enriched boron on some of their leaves. The rate of boron absorption by leaves (measured using neutron capture radiography) was found to be in the range of 1.9 to 5.3 nmol boron per h. This means that it requires several days for a coffee leaf to absorb most of the boron supplied by foliar spray in the usual agronomic treatments. Technically, the use of the method of neutron capture radiography has revealed to be quite sensitive and applicable to liquid micro-samples (a few microL in volume) even with the low-intensity neutron fluxes available in Costa Rica.


Assuntos
Boro/farmacocinética , Café/metabolismo , Folhas de Planta/metabolismo , Absorção , Cinética , Nêutrons , Tecnologia Radiológica , Fatores de Tempo
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