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2.
Rev Sci Instrum ; 94(10)2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37801369

RESUMO

In this paper, a diagnostic for the measurement of the electron cyclotron emission (ECE) from non-thermal electrons in magnetically confined fusion plasmas is presented. The diagnostic employs a vertical viewing line of sight that allows us to directly infer the energy of the emitting electrons. Previous incarnations of this diagnostic on other machines have been limited by refraction, which can cause stray radiation to enter the line of sight, polluting the signal. By tuning the toroidal magnetic field on the Tokamak à Configuration Variable, TCV, and by carefully selecting the range of frequencies that are used to measure the ECE spectrum, refraction can be mitigated and background radiation power reduced to below the noise power of the instrumentation. A novel technique for calibrating the diagnostic based on plasma measurements and modeling has been developed. The paper will describe the Vertical ECE (V-ECE) diagnostic on TCV, the calibration method, and the first results from the measurements.

3.
Trials ; 22(1): 186, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33673867

RESUMO

BACKGROUND: Depression and anxiety impact up to 1 in 5 pregnant and postpartum women worldwide. Yet, as few as 20% of these women are treated with frontline interventions such as evidence-based psychological treatments. Major barriers to uptake are the limited number of specialized mental health treatment providers in most settings, and problems with accessing in-person care, such as childcare or transportation. Task sharing of treatment to non-specialist providers with delivery on telemedicine platforms could address such barriers. However, the equivalence of these strategies to specialist and in-person models remains unproven. METHODS: This study protocol outlines the Scaling Up Maternal Mental healthcare by Increasing access to Treatment (SUMMIT) randomized trial. SUMMIT is a pragmatic, non-inferiority test of the comparable effectiveness of two types of providers (specialist vs. non-specialist) and delivery modes (telemedicine vs. in-person) of a brief, behavioral activation (BA) treatment for perinatal depressive and anxiety symptoms. Specialists (psychologists, psychiatrists, and social workers with ≥ 5 years of therapy experience) and non-specialists (nurses and midwives with no formal training in mental health care) were trained in the BA protocol, with the latter supervised by a BA expert during treatment delivery. Consenting pregnant and postpartum women with Edinburgh Postnatal Depression Scale (EPDS) score of ≥ 10 (N = 1368) will be randomized to one of four arms (telemedicine specialist, telemedicine non-specialist, in-person specialist, in-person non-specialist), stratified by pregnancy status (antenatal/postnatal) and study site. The primary outcome is participant-reported depressive symptoms (EPDS) at 3 months post-randomization. Secondary outcomes are maternal symptoms of anxiety and trauma symptoms, perceived social support, activation levels and quality of life at 3-, 6-, and 12-month post-randomization, and depressive symptoms at 6- and 12-month post-randomization. Primary analyses are per-protocol and intent-to-treat. The study has successfully continued despite the COVID-19 pandemic, with needed adaptations, including temporary suspension of the in-person arms and ongoing randomization to telemedicine arms. DISCUSSION: The SUMMIT trial is expected to generate evidence on the non-inferiority of BA delivered by a non-specialist provider compared to specialist and telemedicine compared to in-person. If confirmed, results could pave the way to a dramatic increase in access to treatment for perinatal depression and anxiety. TRIAL REGISTRATION: ClinicalTrials.gov NCT04153864 . Registered on November 6, 2019.


Assuntos
Ansiedade/terapia , Depressão Pós-Parto/terapia , Depressão/terapia , Acessibilidade aos Serviços de Saúde , Complicações na Gravidez/terapia , Psicoterapia/métodos , Telemedicina/métodos , COVID-19 , Atenção à Saúde/métodos , Estudos de Equivalência como Asunto , Feminino , Humanos , Serviços de Saúde Materna , Serviços de Saúde Mental/organização & administração , Tocologia , Enfermeiras e Enfermeiros , Ensaios Clínicos Pragmáticos como Assunto , Gravidez , Escalas de Graduação Psiquiátrica , Psiquiatria , Psicologia , SARS-CoV-2 , Assistentes Sociais , Especialização
4.
Microbiol Resour Announc ; 9(30)2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32703832

RESUMO

Campylobacter jejuni is the leading cause of bacterial foodborne disease worldwide. Here, we report the complete annotated genomes and plasmid sequences of 17 Campylobacter jejuni strains isolated from patients with gastroenteritis in Santiago, Chile.

7.
Rev Med Interne ; 40(9): 613-616, 2019 Sep.
Artigo em Francês | MEDLINE | ID: mdl-31229357

RESUMO

INTRODUCTION: Propionibacterium acnes endocarditis is rare and difficult to diagnose. We report a case of Propioniacterium acnes endocarditis revealed by a lower limb fasciitis. CASE REPORT: A 54-year-old patient presented with recurrent febrile myalgia of the lower limbs, that appeared three years after an aortic surgery (aortic valve sparing reimplentation and ascending aortic prosthesis implantation). Computer tomography showed fasciitis of both legs. Positron emission tomography showed 18Fluorodeoxyglucose intake of the aortic prosthesis and in muscles of the lower limbs. Ten days after blood sample drawing, cultures showed the presence of Propionibacterium acnes. The aortic prosthesis was surgically removed, whose culture confirmed infection by Propionibacterium acnes. The diagnosis of infective endocarditis revealed by lower limb emboli was made. Evolution was favorable. CONCLUSION: In patients with vascular prostheses, Propionibacterium acnes infection must be evoked face to an atypical inflammatory process. Very prolonged blood culture incubation is needed to identify the pathogen.


Assuntos
Endocardite Bacteriana/diagnóstico , Endocardite Bacteriana/microbiologia , Infecções por Bactérias Gram-Positivas/diagnóstico , Propionibacterium acnes , Endocardite Bacteriana/complicações , Febre/etiologia , Infecções por Bactérias Gram-Positivas/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Mialgia/etiologia
8.
J Hosp Infect ; 102(4): 461-464, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30885815

RESUMO

Coccidioides is a primary pathogenic fungus, which infects humans through highly infectious arthroconidia, causing substantial morbidity including life-threatening disseminated infections. Due to the low infectious dose, laboratory personnel might become infected during diagnostic procedures. Accordingly, coccidioidomycosis is reported as the most frequent laboratory-acquired systemic mycosis worldwide. This risk is aggravated in non-endemic countries, where the diagnosis may not be suspected. We report on an inadvertent exposure of 44 persons to Coccidioides posadasii in a clinical microbiology laboratory in Chile, the measures of containment after rapid diagnosis with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and the lessons learnt in a non-endemic setting.


Assuntos
Coccidioides/isolamento & purificação , Coccidioidomicose/epidemiologia , Infecção Laboratorial/epidemiologia , Chile/epidemiologia , Coccidioidomicose/diagnóstico , Coccidioidomicose/microbiologia , Humanos , Controle de Infecções , Infecção Laboratorial/diagnóstico , Infecção Laboratorial/microbiologia , Técnicas Microbiológicas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
9.
Rev Sci Instrum ; 90(12): 123501, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31893830

RESUMO

This article describes the realization of a novel approach to short pulse (∼1 ns) reflectometry (SPR) recently implemented in the tokamak configuration variable tokamak. Taking advantage of a fast arbitrary waveform generator and vector-network-analyzer extension modules, the design offers flexibility regarding pulse output frequency, duration, and repetition rate. Such flexibility allows the instrument to overcome traditional SPR spatial sampling limitations while reducing hardware complexity. In order to measure the group-delay of nanosecond-scale pulses, both traditional analog and novel digital sampling techniques have been explored. A group-delay range resolution of 17 ps (2.6 mm) in average over the V-band has been achieved with both timing techniques against a waveguide mirror featuring 10 dB power fluctuations. Direct pulse sampling during L-mode plasmas shows that reflected pulse widths increase only by 4% in average. However, pulse width dispersion does occur in L-mode plasmas and leads to an increase in the group-delay uncertainty up to 40 ps (6 mm). Raw histograms of group-delay data show interesting qualitative changes from the L mode to the H-mode. Frequency spectra of group-delay data allow the identification of macroscopic density fluctuations as well as edge quasicoherent modes during edge-localized mode-free H-modes. Finally, fast changes to the density profile have been measured with microsecond time resolution and subcentimeter spatial resolution in both O and X-mode polarizations.

10.
Rev Sci Instrum ; 89(8): 083503, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30184720

RESUMO

A variable configuration V-band heterodyne Doppler back-scattering diagnostic has been recently made operational in the tokamak à configuration variable. This article describes the hardware setup options, flexible quasi-optical launcher antenna, data-analysis techniques, and first data. The diagnostic uses a fast arbitrary waveform generator as the main oscillator and commercial vector network analyzer extension modules as the main mm-wave hardware. It allows sweepable single or multi-frequency operation. A flexible quasi-optical launcher antenna allows 3D poloidal (10°-58°) and toroidal (-180° to 180°) steering of the beam with 0.2° accuracy. A pair of fast HE11 miter-bend polarizers allow flexible coupling to either O or X mode and programmable polarization changes during the shot. These have been used to measure the magnetic-field pitch angle in the edge of the plasma by monitoring the backscattered signal power. Ray-tracing simulations reveal an available k⊥ range between 3 and 16 cm-1 with a resolution of 2-4 cm-1. Perpendicular rotation velocity estimates compare well against ExB plasma poloidal rotation estimates from charge exchange recombination spectroscopy.

11.
Rev Sci Instrum ; 88(8): 083506, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28863634

RESUMO

The correlation electron cyclotron emission diagnostic of tokamak à configuration variable has recently been upgraded. It now has the choice of three lines of sight: two horizontal lines placed on the low field side of the vessel, perpendicular to the magnetic field, and a dual-axis steerable antenna. The polarization of the radiation collected by the latter can be rotated using a universal polarizer situated in the transmission line. This line is also shared with a reflectometry system, allowing simultaneous measurements of temperature and density fluctuations in the same plasma volumes. When using this line, it is possible to choose between two dedicated front ends characterized by different local oscillator frequencies, adding flexibility in the choice of the plasma region to be studied. The intermediate frequency section is now equipped with six frequency tunable YIG filters allowing the study of turbulence properties in a wide range of radial positions. When studying fluctuations over the whole video bandwidth, the minimum detectable fluctuation level is δTe/Te∼0.5%. The new system has been used to measure electron temperature fluctuations over a large fraction of the plasma profiles in a series of plasmas with triangularity varying from 0.6 to -0.6 but comparable collisionality profiles.

12.
New Microbes New Infect ; 18: 50-53, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28626584

RESUMO

Invasive amoebiasis is a life-threatening infection requiring immediate detection and treatment. However, diagnosis is challenging because conventional methods such as light microscopy and serology are unreliable. Molecular techniques are therefore considered the new diagnostic reference standard, but most of the developed assays are research tools and not widely available. Recently commercial multiplex PCR panels have been introduced which permit the simultaneous detection of multiple enteric pathogens including Entamoeba histolytica in stool samples. Our report demonstrates for the first time that these new assays might also serve as a rapid tool to diagnose amoebic liver abscess in patients with cystic focal liver lesions.

14.
Phys Rev Lett ; 108(20): 206103, 2012 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-23003159

RESUMO

We discuss the inhomogeneous stress relaxation of a monolayer of hexahydroxytriphenylene (HHTP) which adopts the rare line-on-line (LOL) coincidence on KCl(001) and forms moiré patterns. The fact that the hexagonal HHTP layer is uniaxially compressed along the LOL makes this system an ideal candidate to discuss the influence of inhomogeneous stress relaxation. Our work is a combination of noncontact atomic force microscopy experiments, density functional theory and potential energy calculations, and a thorough interpretation by means of the Frenkel-Kontorova model. We show that the assumption of a homogeneous molecular layer is not valid for this organic-inorganic heteroepitaxial system since the best calculated energy configuration correlates with the experimental data only if inhomogeneous relaxations of the layer are taken into account.

15.
Med Mal Infect ; 40(5): 256-67, 2010 May.
Artigo em Francês | MEDLINE | ID: mdl-19951829

RESUMO

Malaria and HIV are two major public health issues, especially in sub-Saharan Africa. HIV infection increases the incidence of clinical malaria, inversely correlated with the degree of immunodepression. The effect of malaria on HIV infection is not as well established. Malaria, when fever and parasitemia are high, may be associated with transient increases in HIV viral load. The effect of subclinical malaria on HIV viral load is uncertain. During pregnancy, placental malaria is associated with higher plasma and placental HIV viral loads, independently of the severity of immunodeficiency. However, the clinical impact of these transient increases of HIV viral load remains unknown. Although some data suggests that malaria might enhance sexual and mother-to-child transmissions, no clinical study has confirmed this. Nevertheless pregnant women and children with malaria-induced anemia are also exposed to HIV through blood transfusions. Integrated HIV and malaria control programs in the regions where both infections overlap are necessary.


Assuntos
Infecções por HIV/complicações , Malária/complicações , Contagem de Linfócito CD4 , Progressão da Doença , Infecções por HIV/sangue , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Humanos , Malária/epidemiologia
16.
Phys Rev E Stat Nonlin Soft Matter Phys ; 77(1 Pt 2): 016407, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18351944

RESUMO

Fast ions created in the fusion processes will provide up to 70% of the heating in ITER. To optimize heating and current drive in magnetically confined plasmas insight into fast-ion dynamics is important. First measurements of such dynamics by collective Thomson scattering (CTS) were recently reported [Bindslev, Phys. Rev. Lett. 97, 205005 2006]. Here we extend the discussion of these results which were obtained at the TEXTOR tokamak. The fast ions are generated by neutral-beam injection and ion-cyclotron resonance heating. The CTS system uses 100-150kW of 110-GHz gyrotron probing radiation which scatters off the collective plasma fluctuations driven by the fast-ion motion. The technique measures the projected one-dimensional velocity distribution of confined fast ions in the scattering volume where the probe and receiver beams cross. By shifting the scattering volume a number of scattering locations and different resolved velocity components can be measured. The temporal resolution is 4ms while the spatial resolution is approximately 10cm depending on the scattering geometry. Fast-ion velocity distributions in a variety of scenarios are measured, including the evolution of the velocity distribution after turnoff of the ion heating. These results are in close agreement with numerical simulations.

17.
Nanotechnology ; 19(30): 305501, 2008 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-21828762

RESUMO

Recently, we investigated the adsorption of octachloro zinc phthalocyanine (ZnPcCl(8)) on Ag(111) by scanning tunneling microscopy. Compared to the standard phthalocyanine, halogenated phthalocyanine molecules show a much more complex binding behavior, which results in the formation of three different structural phases. These phases follow from the ordering process with the formation of 8, 4 and 0 intermolecular hydrogen-halogen bonds (Abel et al 2006 ChemPhysChem 7 82). In the present work we investigate these phases by Kelvin probe force microscopy in order to quantitatively deduce the electric interface barrier of the first monolayer. Our measurements reveal that the binding behavior does not only affect the structural ordering but also the interface dipole formation, which leads to different work functions. The fact that we observe interface barriers of opposite signs between ordered and disordered molecular layers underlines the importance of exactly knowing the molecular arrangement at the interface when assembling organic molecule devices.

18.
Med Mal Infect ; 37(10): 629-36, 2007 Oct.
Artigo em Francês | MEDLINE | ID: mdl-17628374

RESUMO

Malaria and HIV are two major public health issues, especially in sub-Saharan Africa. The impact of HIV infection on malaria depends on the patient's immune status: immunodepression level but also immunity against Plasmodium. HIV infection increases the incidence of clinical malaria, inversely correlated with the degree of immunodepression, but the severity and mortality are increased only in areas of unstable malaria. In severe malaria the level of parasitemia is similar in HIV-positive and HIV-negative patients. During pregnancy, HIV infection increases the incidence of clinical malaria, maternal morbidity, and fetal and neonatal morbi-mortality. Sulfa-based therapies reduce the risk of malaria, most importantly in pregnancy. HIV infection increases the risk of treatment failure, mainly with sulfa-based therapies, due to re-infection or parasitic recrudescence. Further studies are needed to determine the pathophysiological interactions between HIV infection and malaria.


Assuntos
Infecções por HIV/complicações , Malária/complicações , Adulto , África Subsaariana/epidemiologia , Feminino , Geografia , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Humanos , Malária/epidemiologia , Malária/transmissão , Gravidez , Complicações Infecciosas na Gravidez/virologia
19.
J Chem Phys ; 126(4): 044709, 2007 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-17286501

RESUMO

In this study synchrotron radiation was used to investigate the electronic properties of a thin film of zinc-phthalocyanine (ZnPc) deposited on Si(001)-2x1 and progressively doped with K atoms. The molecular orientation was probed by angular-dependent x-ray absorption spectroscopy and the molecules were found to lie with the macrocycle plane roughly perpendicular to the surface. The evolution of the electronic properties of the film was then followed by measuring the photoemission spectra upon in situ evaporation of K atoms on the pristine ZnPc film. The results show that doping proceeds through charge donation from the K atoms to the molecular units whose lowest unoccupied molecular orbital (LUMO) becomes progressively filled. Despite the fact that the LUMO spectral weight increases as the stoichiometry x in the K(x)ZnPc compound varies from about 1 to 4 (as determined by core level photoemission), no detectable density of states was observed at the Fermi level, showing that the film remains insulating for all the investigated stoichiometries. On the other hand the C 1s spectra, which appear merely broadened at the earliest stages of doping (x approximately 1), clearly develop two distinct components when x exceeds 2, suggesting that the charge state is not the same for all the molecules. At the same time, the modification of the valence band points towards the coexistence of two distinct phases with x=2 and x=4.

20.
Phys Rev Lett ; 97(20): 205005, 2006 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-17155690

RESUMO

Here we present the first measurements by collective Thomson scattering of the evolution of fast-ion populations in a magnetically confined fusion plasma. 150 kW and 110 Ghz radiation from a gyrotron were scattered in the TEXTOR tokamak plasma with energetic ions generated by neutral beam injection and ion cyclotron resonance heating. The temporal behavior of the spatially resolved fast-ion velocity distribution is inferred from the received scattered radiation. The fast-ion dynamics at sawteeth and the slowdown after switch off of auxiliary heating is resolved in time. The latter is shown to be in close agreement with modeling results.

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