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1.
Proc Natl Acad Sci U S A ; 111(35): 12661-6, 2014 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-24821792

RESUMEN

The Gemini Planet Imager is a dedicated facility for directly imaging and spectroscopically characterizing extrasolar planets. It combines a very high-order adaptive optics system, a diffraction-suppressing coronagraph, and an integral field spectrograph with low spectral resolution but high spatial resolution. Every aspect of the Gemini Planet Imager has been tuned for maximum sensitivity to faint planets near bright stars. During first-light observations, we achieved an estimated H band Strehl ratio of 0.89 and a 5-σ contrast of 10(6) at 0.75 arcseconds and 10(5) at 0.35 arcseconds. Observations of Beta Pictoris clearly detect the planet, Beta Pictoris b, in a single 60-s exposure with minimal postprocessing. Beta Pictoris b is observed at a separation of 434 ± 6 milliarcseconds (mas) and position angle 211.8 ± 0.5°. Fitting the Keplerian orbit of Beta Pic b using the new position together with previous astrometry gives a factor of 3 improvement in most parameters over previous solutions. The planet orbits at a semimajor axis of [Formula: see text] near the 3:2 resonance with the previously known 6-AU asteroidal belt and is aligned with the inner warped disk. The observations give a 4% probability of a transit of the planet in late 2017.

2.
Appl Opt ; 55(2): 323-40, 2016 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-26835769

RESUMEN

The Gemini Planet Imager's adaptive optics (AO) subsystem was designed specifically to facilitate high-contrast imaging. A definitive description of the system's algorithms and technologies as built is given. 564 AO telemetry measurements from the Gemini Planet Imager Exoplanet Survey campaign are analyzed. The modal gain optimizer tracks changes in atmospheric conditions. Science observations show that image quality can be improved with the use of both the spatially filtered wavefront sensor and linear-quadratic-Gaussian control of vibration. The error budget indicates that for all targets and atmospheric conditions AO bandwidth error is the largest term.

3.
JMIR Mhealth Uhealth ; 12: e54579, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38865173

RESUMEN

BACKGROUND: Chronic pain affects approximately 30% of the general population, severely degrades quality of life and professional life, and leads to additional health care costs. Moreover, the medical follow-up of patients with chronic pain remains complex and provides only fragmentary data on painful daily experiences. This situation makes the management of patients with chronic pain less than optimal and may partly explain the lack of effectiveness of current therapies. Real-life monitoring of subjective and objective markers of chronic pain using mobile health (mHealth) programs could better characterize patients, chronic pain, pain medications, and daily impact to help medical management. OBJECTIVE: This cohort study aimed to assess the ability of our mHealth tool (eDOL) to collect extensive real-life medical data from chronic pain patients after 1 year of use. The data collected in this way would provide new epidemiological and pathophysiological data on chronic pain. METHODS: A French national cohort of patients with chronic pain treated at 18 pain clinics has been established and followed up using mHealth tools. This cohort makes it possible to collect the determinants and repercussions of chronic pain and their evolutions in a real-life context, taking into account all environmental events likely to influence chronic pain. The patients were asked to complete several questionnaires, body schemes, and weekly meters, and were able to interact with a chatbot and use educational modules on chronic pain. Physicians could monitor their patients' progress in real time via an online platform. RESULTS: The cohort study included 1427 patients and analyzed 1178 patients. The eDOL tool was able to collect various sociodemographic data; specific data for characterizing pain disorders, including body scheme; data on comorbidities related to chronic pain and its psychological and overall impact on patients' quality of life; data on drug and nondrug therapeutics and their benefit-to-risk ratio; and medical or treatment history. Among the patients completing weekly meters, 49.4% (497/1007) continued to complete them after 3 months of follow-up, and the proportion stabilized at 39.3% (108/275) after 12 months of follow-up. Overall, despite a fairly high attrition rate over the follow-up period, the eDOL tool collected extensive data. This amount of data will increase over time and provide a significant volume of health data of interest for future research involving the epidemiology, care pathways, trajectories, medical management, sociodemographic characteristics, and other aspects of patients with chronic pain. CONCLUSIONS: This work demonstrates that the mHealth tool eDOL is able to generate a considerable volume of data concerning the determinants and repercussions of chronic pain and their evolutions in a real-life context. The eDOL tool can incorporate numerous parameters to ensure the detailed characterization of patients with chronic pain for future research and pain management. TRIAL REGISTRATION: ClinicalTrials.gov NCT04880096; https://clinicaltrials.gov/ct2/show/NCT04880096.


Asunto(s)
Dolor Crónico , Aplicaciones Móviles , Humanos , Dolor Crónico/terapia , Dolor Crónico/psicología , Femenino , Masculino , Persona de Mediana Edad , Estudios de Cohortes , Francia/epidemiología , Aplicaciones Móviles/normas , Aplicaciones Móviles/estadística & datos numéricos , Adulto , Anciano , Encuestas y Cuestionarios , Internet , Estudios de Seguimiento , Telemedicina/estadística & datos numéricos , Calidad de Vida/psicología
4.
Trials ; 25(1): 613, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39285437

RESUMEN

BACKGROUND: Non-steroidal anti-inflammatory drugs (NSAIDs) are recommended for the management of acute postoperative pain as part of a multimodal strategy to reduce opioid use, relieve pain, and reduce chronic pain in non-cardiac surgery. However, significant concerns arise in cardiac surgery due to the potential adverse effects of NSAID including increased bleeding and acute kidney injury (AKI). We hypothesized that NSAIDs are effective against pain and safe in the early postoperative period following cardiac surgery, taking contraindications into account. METHODS: The KETOPAIN trial is a prospective, double blind, 1:1 ratio, versus placebo multicentric trial, randomizing 238 patients scheduled for cardiac surgery. Written consent will be obtained for all participants. The inclusion criterion is patients more than 18 years old undergoing for elective cardiac surgery under cardiopulmonary bypass (CPB). Patients will be allocated to the intervention (ketoprofen) group (n = 119) or the control (placebo) group (n = 119). In the intervention group, in addition to the standard treatment, patients will receive NSAIDs (ketoprofen) at a dose of 100 mg each 12 h 48 h after. The control group, in addition to the standard treatment, will receive a placebo of NSAIDs every 12 h for 48 h after surgery. An intention-to-treat analysis will be performed. The primary endpoint will be the intensity of acute postoperative pain at rest at 24 h from the end of surgery. Pain will be assessed using the numerous rating scale. The secondary endpoints will be postoperative pain on coughing during chest physiotherapy, postoperative pain until day 7, the pain trajectory between day 3 and day 7, cumulative opioid consumption within 48 h after surgery, nausea and vomiting, the occurrence of postoperative pulmonary complications within the first 7 days after surgery, neuropathic pain at 3 months, and quality of life at 3 months. DISCUSSION: NSAIDs function as non-selective, reversible inhibitors of the cyclooxygenase enzyme and play a role in a multimodal pain management approach. While there are recommendations supporting the use of NSAIDs in major non-cardiac surgery, recent guidelines do not favor their use in cardiac surgery. However, this is based on low-quality evidence. Major concerns regarding NSAID use in cardiac surgery patients are potential increase in postoperative bleeding or AKI. However, few studies support the possible use of NSAIDs without the risk of bleeding and/or AKI. Also, in a recent French survey, many anesthesiologists reported using NSAIDs in cardiac surgery. To date, no large randomized study has been conducted to evaluate the efficacy of NSAIDs in the management of postoperative pain in cardiac surgery. The expected outcome of this study is an improvement in the management of acute postoperative pain in cardiac surgery with a multimodal strategy including the use of NSAIDs. TRIAL REGISTRATION: ClinicalTrials.gov NCT06381063. Registered on April 24, 2024.


Asunto(s)
Antiinflamatorios no Esteroideos , Procedimientos Quirúrgicos Cardíacos , Cetoprofeno , Dolor Postoperatorio , Humanos , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/diagnóstico , Dolor Postoperatorio/etiología , Dolor Postoperatorio/prevención & control , Método Doble Ciego , Antiinflamatorios no Esteroideos/uso terapéutico , Antiinflamatorios no Esteroideos/efectos adversos , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Estudios Prospectivos , Cetoprofeno/uso terapéutico , Cetoprofeno/efectos adversos , Cetoprofeno/administración & dosificación , Dimensión del Dolor , Resultado del Tratamiento , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Tiempo
5.
Appl Opt ; 52(14): 3394-403, 2013 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-23669856

RESUMEN

Modern coronagraphic systems require very precise alignment between optical components and can benefit greatly from automated image processing. We discuss three techniques commonly employed in the fields of computer vision and image analysis as applied to the Gemini Planet Imager, a new facility instrument for the Gemini South Observatory. We describe how feature extraction and clustering methods can be used to aid in automated system alignment tasks, and also present a search algorithm for finding regular features in science images used for calibration and data processing. Along with discussions of each technique, we present our specific implementation and show results of each one in operation.

6.
Therapie ; 78(6): 721-732, 2023.
Artículo en Francés | MEDLINE | ID: mdl-36586751

RESUMEN

INTRODUCTION: In France, the number of hospitals involved in clinical research and committed to a quality approach is increasing. The objective of such approaches is to ensure the safety of patients involved in research projects by improving quality. OBJECTIVE: The University Hospital of Amiens has chosen to certify all its clinical research activities in the same scope according to the ISO 9001: 2015 standard. METHODS: Action planning has been established and a head of quality management has been appointed to oversee this process. RESULTS: The activities in the five departments of our university hospital jointly certified in December 2019, are: activities related to internal and external sponsors, as well as methodology and monitoring of clinical research projects conducted in the Clinical Research and Innovation Department (CRID); help with clinical research investigations in the Clinical Research Center (CRC); management of the pathway of therapeutic units used in clinical research (excluding the manufacture of drugs) in the Clinical Trials Unit (CTU) of the Hospital Pharmacy; the conservation and provision of biological resources (tissues and fluids) for cancer research in the Tumor bank of Picardy; the collection, reception, preparation, quality control, conservation and provision of biological resources for research purposes. These activities fall within the framework of legal and regulatory activities and the provision of secure storage in the Biological Resources Center already ISO 9001 certified since 2004 and NF S96-900: 2011 certified since 2009. CONCLUSIONS: The choice of a common quality approach has brought together more than 70 persons from 5 departments involved in clinical research projects within a single certificate with the aim of continuous improvement.


Asunto(s)
Certificación , Humanos , Hospitales Universitarios , Control de Calidad , Francia
7.
Appl Opt ; 51(36): 8769-78, 2012 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-23262616

RESUMEN

The ability to simulate atmospheric turbulence in the laboratory is a crucial part of testing and developing astronomical adaptive optics (AO) technology. We report on the development of a technique for creating phase plates that involves the strategic application of clear acrylic paint onto a transparent substrate. Results of interferometric characterization of these plates are described and compared to Kolmogorov statistics. The range of r(0) (Fried's parameter) achieved thus far is 0.2-1.2 mm, with a Kolmogorov power law. These phase plates have been successfully used by the Laboratory for Adaptive Optics at University of California, Santa Cruz in the Multi-Conjugate Adaptive Optics testbed as part of the Visible Light Laser Guidestar Experiments (Villages) calibration system and during integration and testing of the Gemini Planet Imager. Measurements of the turbulence from the plate in Villages are compared to the sky, which shows the plate produces good representative atmospheric aberrations. We are now distributing the plates to other members of the AO community.

8.
Ther Adv Musculoskelet Dis ; 14: 1759720X211066233, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35069809

RESUMEN

INTRODUCTION: Despite their poor tolerance, especially in the elderly, weak opioids (WO) remain commonly prescribed for patients with knee osteoarthritis (KOA). We compared the efficacy and safety of a new wearable transcutaneous electrical nerve stimulation (W-TENS) device with WO for the treatment of moderate-to-severe, nociceptive KOA chronic pain. METHODS: The study was a non-inferiority, multicentric, prospective, randomized, single-blind, controlled, 2-parallel groups Trial. A total of 110 patients with KOA were included (Kellgren-Lawrence radiographic grade ⩾2; American College of Rheumatology criteria), with chronic moderate-to-severe nociceptive pain (mean 8-day pain intensity (PI) ⩾ 4 on an 11-point numerical rating scale), in failure to non-opioid analgesics, including nonsteroidal anti-inflammatory drugs (NSAIDs). Patients with neuropathic pain were excluded. The co-primary endpoints were mean PI at 3 months (M3) and number of potentially treatment-related adverse events (TRAEs). Secondary outcomes included Western Ontario MAC Master University function subscale (range, 0-68), additional pain and quality of life measures, and responder rates. RESULTS: The non-inferiority of W-TENS was demonstrated in both the per protocol (PP) and intent-to-treat (ITT) populations. At M3, PI in PP population was 3.87 (2.12) compared with 4.66 (2.37) [delta: -0.79 (0.44); 95% CI (-1.65, 0.08)] in W-TENS and WO groups, respectively. A planned superiority analysis showed a significant superiority of W-TENS over WO on PI at M3 (p = 0.0124). The number of TRAEs was significantly lower in the W-TENS group (n = 7) than in the WO group (n = 36) (p < 0.001). Other secondary outcomes also favored W-TENS. CONCLUSION: W-TENS was more effective and better tolerated than WO in the treatment of chronic nociceptive KOA pain and offers an interesting non-pharmacological analgesic alternative in the management of KOA.Trial Registration: ClinicalTrials.gov: NCT03902340.

9.
PLoS One ; 16(2): e0246636, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33556081

RESUMEN

BACKGROUND: Data on microcirculatory pattern of COVID-19 critically ill patients are scarce. The objective was to compare sublingual microcirculation parameters of critically ill patients according to the severity of the disease. METHODS: The study is a single-center prospective study with critically ill COVID-19 patients admitted in ICU. Sublingual microcirculation was assessed by IDF microscopy within 48 hours of ICU admission. Microcirculatory flow index (MFI), proportion of perfused vessel (PPV), total vessel density (TVD), De Backer score (DBS), perfused vessel density (PVD) and heterogeneity index (HI) were assessed. Patients were divided in 2 groups (severe and critical) according to the World health organization definition. FINDINGS: From 19th of March to 7th of April 2020, 43 patients were included. Fourteen patients (33%) were in the severe group and twenty-nine patients (67%) in the critical group. Patients in the critical group were all mechanically ventilated. The critical group had significantly higher values of MFI, DBS and PVD in comparison to severe group (respectively, PaCO2: 49 [44-45] vs 36 [33-37] mmHg; p<0,0001, MFI: 2.8 ± 0.2 vs 2.5 ± 0.3; p = 0.001, DBS: 12.7 ± 2.6 vs 10.8 ± 2.0 vessels mm-2; p = 0.033, PVD: 12.5 ± 3.0 vs 10.1 ± 2.4 mm.mm-2; p = 0.020). PPV, HI and TVD were similar between groups Correlation was found between microcirculatory parameters and PaCO2 levels. CONCLUSION: Critical COVID-19 patients under mechanical ventilation seem to have higher red blood cell velocity than severe non-ventilated patients.


Asunto(s)
COVID-19/fisiopatología , Enfermedad Crítica , Microcirculación/fisiología , Microvasos/fisiopatología , Anciano , COVID-19/virología , Dióxido de Carbono/metabolismo , Femenino , Hemodinámica , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Oxígeno/metabolismo , Presión Parcial , Estudios Prospectivos , SARS-CoV-2/fisiología
10.
Appl Opt ; 49(3): 394-402, 2010 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-20090803

RESUMEN

The next generation of adaptive optics will depend on laser guide stars to increase sky coverage. However, there are a few limitations. The thickness of the sodium layer in the mesosphere at 90 km causes spot elongation, which is more severe for large telescopes. Moreover, the outer-edge subaperture of such large telescopes will resolve variations of sodium atom density seen over the thick layer. We quantify these density fluctuations using real data taken at Lick Observatory. We used the 1 m Nickel telescope to image the return flux due to laser-induced fluorescence from a dye laser launched from the nearby 3 m Shane telescope. This view was from the side allowing the resolution of the sodium return as a function of height. We used drift scanning of the 1 m telescope to provide resolution in time. We show qualitative images of the sodium distribution for different nights and quantitatively study the temporal power spectra of those fluctuations. We conclude that the sodium profiles have an average full width half-maximum of 10 km. However, the extent beyond the nominal 10 km thickness is important for accurate wavefront sensing. The variations in the height of the sodium layer occur on short enough time scales that AO systems for 30 m class telescopes will likely need focus updates on time scales shorter than 100 ms.

11.
Appl Opt ; 48(21): 4077-89, 2009 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-19623221

RESUMEN

High-contrast imaging techniques such as coronagraphy are expected to play an important role in the imaging of extrasolar planets. Instruments like the Gemini Planet Imager (GPI) or the Spectro-Polar-Imetric High-Contrast Exoplanet Research (SPHERE) require high-dynamic range, achieved using coronagraphs to block light coming from the parent star. An extremely good adaptive optics (AO) system is required to reduce dynamic atmospheric wavefront errors to 50-100 nm rms. Systematic wavefront errors must also be controlled at the nanometer-equivalent level to remove persistent speckle artifacts. While precision AO systems can control wavefront phase errors at this level, systematic amplitude or intensity errors can also produce speckle artifacts and are uncontrolled by traditional AO phase conjugation. On the Laboratory for Adaptive Optics (LAO) extreme AO testbed, we observed a discrepancy between the coronagraphic image profile and the profile predicted by simple simulations using the measured optical phase, which could potentially be explained by amplitude variations. Measurements showed up to 7% rms intensity changes across the microelectrical mechanical (MEM) plane of the system. We identified potential sources of amplitude variation and compared them to a Fresnel model of the system. One potential concern was the surface structure of the MEM system's (MEMS) deformable mirror, but analysis shows that it induces at most 2% rms variation. The bulk of the observed intensity variation is due to nonuniform illumination of the system by the input single-mode fiber and phase errors mixing into amplitude at the nonpupil-plane due to the Talbot effect, coupled with residual astigmatism in the pupil imager.

12.
J Environ Radioact ; 126: 20-31, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23933083

RESUMEN

Sediment cores were collected at the outlet of the highly anthropogenized catchment of the Seine River at two contrasting sites: a flood plain of the lower Seine River and a quasi-permanently submerged harbour basin (or wet dock) in the upper tidal estuary. Analyses of artificial radionuclides ((137)Cs and plutonium isotopes), coupled with hydrological and bathymetric data, lead to a precise dating of the sediment cores collected at the two sites. (137)Cs signals originating from global fallout (early 1960s) and from the Chernobyl accident (1986) are identified, but at different levels due to the incomplete nature or variable continuity of the records. Anomalous (238)Pu concentrations found at both sites (1-2 Bq kg(-1)) are attributed to unknown industrial releases originating from upstream. Interpolating (137)Cs sediment activities under the assumption of a constant sediment rate, those releases were dated back to 1975 ± 1, thus providing a local but reliable time-marker. Age models have highlighted a very contrasting sediment filling dynamics in these two sites. This study presents the first sediment record of alpha- and gamma-emitting artificial radionuclides obtained at the outlet of the huge catchment area of the River Seine, over a period covering the last 50 years.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos/análisis , Ríos , Radioisótopos de Cesio/análisis , Plutonio/análisis , Contaminantes Radiactivos del Agua/análisis
13.
Appl Opt ; 47(9): 1317-26, 2008 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-18709080

RESUMEN

A 32 x 32 microelectricalmechanical systems mirror is controlled in a closed-loop adaptive optics test bed with a spatially filtered wavefront sensor (WFS), Fourier transform wavefront reconstruction, and calibration of references with a high-precision interferometer. When correcting the inherent aberration of the mirror, 0.7 nm rms phase error in the controllable band is achieved. When correcting an etched phase plate with atmospheric statistics, a dark hole 10(3) deeper than the uncontrollable phase is produced in the phase power spectral density. Compensation of the mirror's influence function is done with a Fourier filter, which results in improved loop convergence. Use of the spatial filter is shown to reduce the gain variability of the WFS in a quadcell configuration.

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