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1.
Health Econ Rev ; 11(1): 43, 2021 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-34734323

RESUMEN

OBJECTIVES: The aim was to determine the direct impact of the COVID-19 pandemic on Spain's health budget. METHODS: Budget impact analyses based on retrospective data from patients with suspected severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) admitted to a Spanish hospital between February 26 and May 21, 2020. Direct medical costs from the perspective of the hospital were calculated. We analyzed diagnostic tests, drugs, medical and nursing care, and isolation ward and ICU stays for three cohorts: patients seen in the emergency room only, hospitalized patients who tested positive for SARS-CoV-2, and patients who tested negative. RESULTS: The impact on the hospital's budget for the 3 months was calculated at €15,633,180, 97.4% of which was related to health care and hospitalization. ICU stays accounted for 5.3% of the total costs. The mean cost per patient was €10,744. The main costs were staffing costs (10,131 to 11,357 €/patient for physicians and 10,274 to 11,215 €/patient for nurses). Scenario analysis showed that the range of hospital expenditure was between €14,693,256 and €16,524,924. The median impact of the pandemic on the Spanish health budget in the sensitivity analysis using bootstrapped individual data was €9357 million (interquartile range [IQR], 9071 to 9689) for the conservative scenario (113,588 hospital admissions and 11,664 ICU admissions) and €10,385 million (IQR, 110,030 to 10,758) for the worst-case scenario (including suspected cases). CONCLUSION: The impact of COVID-19 on the Spanish public health budget (12.3% of total public health expenditure) is greater than multiple sclerosis, cancer and diabetes cost.

2.
Rev Sci Instrum ; 91(4): 043902, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32357733

RESUMEN

We report details of an experimental platform implemented at the National Ignition Facility to obtain in situ powder diffraction data from solids dynamically compressed to extreme pressures. Thin samples are sandwiched between tamper layers and ramp compressed using a gradual increase in the drive-laser irradiance. Pressure history in the sample is determined using high-precision velocimetry measurements. Up to two independently timed pulses of x rays are produced at or near the time of peak pressure by laser illumination of thin metal foils. The quasi-monochromatic x-ray pulses have a mean wavelength selectable between 0.6 Å and 1.9 Å depending on the foil material. The diffracted signal is recorded on image plates with a typical 2θ x-ray scattering angle uncertainty of about 0.2° and resolution of about 1°. Analytic expressions are reported for systematic corrections to 2θ due to finite pinhole size and sample offset. A new variant of a nonlinear background subtraction algorithm is described, which has been used to observe diffraction lines at signal-to-background ratios as low as a few percent. Variations in system response over the detector area are compensated in order to obtain accurate line intensities; this system response calculation includes a new analytic approximation for image-plate sensitivity as a function of photon energy and incident angle. This experimental platform has been used up to 2 TPa (20 Mbar) to determine the crystal structure, measure the density, and evaluate the strain-induced texturing of a variety of compressed samples spanning periods 2-7 on the periodic table.

4.
Rev Sci Instrum ; 90(1): 013506, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30709229

RESUMEN

The sensitivity of Fuji SR and MS image plates (IPs) used in x-ray spectrometers on OMEGA and the National Ignition Facility has been measured using two techniques. A set of radioisotopes has been used to constrain image-plate sensitivity between 6 and 60 keV, while a Manson source has been used to expose image plates to x rays at energies between 1.5 and 8 keV. These data have shown variation in sensitivity on the order of 5% for a given IP type and scanner settings. The radioisotope technique has also been used to assess IP fading properties for MS-type plates over long times. IP sensitivity as a function of scanner settings and pixel size has been systematically examined, showing variations of up to a factor of 2 depending on the IP type. Cross-calibration of IP scanners at different facilities is necessary to produce a consistent absolute sensitivity curve spanning the energy range of 2-60 keV.

5.
Phys Rev Lett ; 121(9): 095002, 2018 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-30230893

RESUMEN

We report on the first multilocation electron temperature (T_{e}) and flow measurements in an ignition hohlraum at the National Ignition Facility using the novel technique of mid-Z spectroscopic tracer "dots." The measurements define a low resolution "map" of hohlraum plasma conditions and provide a basis for the first multilocation tests of particle and energy transport physics in a laser-driven x-ray cavity. The data set is consistent with classical heat flow near the capsule but reduced heat flow near the laser entrance hole. We evaluate the role of kinetic effects, self-generated magnetic fields, and instabilities in causing spatially dependent heat transport in the hohlraum.

6.
Phys Rev Lett ; 120(5): 055001, 2018 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-29481170

RESUMEN

Planar laser-plasma interaction (LPI) experiments at the National Ignition Facility (NIF) have allowed access for the first time to regimes of electron density scale length (∼500 to 700 µm), electron temperature (∼3 to 5 keV), and laser intensity (6 to 16×10^{14} W/cm^{2}) that are relevant to direct-drive inertial confinement fusion ignition. Unlike in shorter-scale-length plasmas on OMEGA, scattered-light data on the NIF show that the near-quarter-critical LPI physics is dominated by stimulated Raman scattering (SRS) rather than by two-plasmon decay (TPD). This difference in regime is explained based on absolute SRS and TPD threshold considerations. SRS sidescatter tangential to density contours and other SRS mechanisms are observed. The fraction of laser energy converted to hot electrons is ∼0.7% to 2.9%, consistent with observed levels of SRS. The intensity threshold for hot-electron production is assessed, and the use of a Si ablator slightly increases this threshold from ∼4×10^{14} to ∼6×10^{14} W/cm^{2}. These results have significant implications for mitigation of LPI hot-electron preheat in direct-drive ignition designs.

7.
Bone Joint J ; 100-B(1): 73-80, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29305454

RESUMEN

AIMS: The aim of this meta-analysis was to assess the safety and efficacy of collagenase clostridium histolyticum compared with fasciectomy and percutaneous needle fasciotomy (PNF) for Dupuytren's disease. MATERIALS AND METHODS: We systematically searched PubMed, EMBASE, LILACS, Web of Science, Cochrane, Teseo and the ClinicalTrials.gov registry for clinical trials and cohort or case-control studies which compared the clinical outcomes and adverse effects of collagenase with those of fasciectomy or PNF. Of 1345 articles retrieved, ten were selected. They described the outcomes of 425 patients treated with collagenase and 418 treated by fasciectomy or PNF. Complications were assessed using inverse-variance weighted odds ratios (ORs). Clinical efficacy was assessed by differences between the means for movement of the joint before and after treatment. Dose adjustment was applied in all cases. RESULTS: Random-effects modelling showed that patients treated with collagenase had 3.24 increased odds of adverse effects compared with those treated by fasciectomy (OR 4.39) or PNF (OR 1.72,). The effect was lost when only major complications were assessed. Joint movement analysis revealed a difference between means of less than 10%, indicating equivalent clinical efficacy in the short and medium term for collagenase and fasciectomy. We were unable to analyse this for PNF due to a shortage of data. CONCLUSION: There were no significant differences in effect size between collagenase and fasciectomy. The use of collagenase was associated with a higher overall risk of adverse effects than both fasciectomy and PNF. Cite this article: Bone Joint J 2018;100-B:73-80.


Asunto(s)
Contractura de Dupuytren/tratamiento farmacológico , Colagenasa Microbiana/uso terapéutico , Contractura de Dupuytren/cirugía , Fasciotomía/efectos adversos , Fasciotomía/métodos , Humanos , Inyecciones Intralesiones , Colagenasa Microbiana/administración & dosificación , Colagenasa Microbiana/efectos adversos , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Resultado del Tratamiento
8.
Phys Plasmas ; 24(6): 063301, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29104422

RESUMEN

Direct drive implosions of plastic capsules have been performed at the National Ignition Facility to provide a broad-spectrum (500-2000 eV) X-ray continuum source for X-ray transmission spectroscopy. The source was developed for the high-temperature plasma opacity experimental platform. Initial experiments using 2.0 mm diameter polyalpha-methyl styrene capsules with ∼20 µm thickness have been performed. X-ray yields of up to ∼1 kJ/sr have been measured using the Dante multichannel diode array. The backlighter source size was measured to be ∼100 µm FWHM, with ∼350 ps pulse duration during the peak emission stage. Results are used to simulate transmission spectra for a hypothetical iron opacity sample at 150 eV, enabling the derivation of photometrics requirements for future opacity experiments.

9.
Phys Plasmas ; 24(5): 056312, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28611532

RESUMEN

For several years, we have been calculating the radiation drive in laser-heated gold hohlraums using flux-limited heat transport with a limiter of 0.15, tabulated values of local thermodynamic equilibrium gold opacity, and an approximate model for not in a local thermodynamic equilibrium (NLTE) gold emissivity (DCA_2010). This model has been successful in predicting the radiation drive in vacuum hohlraums, but for gas-filled hohlraums used to drive capsule implosions, the model consistently predicts too much drive and capsule bang times earlier than measured. In this work, we introduce a new model that brings the calculated bang time into better agreement with the measured bang time. The new model employs (1) a numerical grid that is fully converged in space, energy, and time, (2) a modified approximate NLTE model that includes more physics and is in better agreement with more detailed offline emissivity models, and (3) a reduced flux limiter value of 0.03. We applied this model to gas-filled hohlraum experiments using high density carbon and plastic ablator capsules that had hohlraum He fill gas densities ranging from 0.06 to 1.6 mg/cc and hohlraum diameters of 5.75 or 6.72 mm. The new model predicts bang times to within ±100 ps for most experiments with low to intermediate fill densities (up to 0.85 mg/cc). This model predicts higher temperatures in the plasma than the old model and also predicts that at higher gas fill densities, a significant amount of inner beam laser energy escapes the hohlraum through the opposite laser entrance hole.

10.
Rev Sci Instrum ; 87(11): 11E327, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27910341

RESUMEN

The electron temperature at stagnation of an ICF implosion can be measured from the emission spectrum of high-energy x-rays that pass through the cold material surrounding the hot stagnating core. Here we describe a platform developed on the National Ignition Facility where trace levels of a mid-Z dopant (krypton) are added to the fuel gas of a symcap (symmetry surrogate) implosion to allow for the use of x-ray spectroscopy of the krypton line emission.

11.
Rev Sci Instrum ; 87(11): 11E321, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27910418

RESUMEN

The high fuel capsule compression required for indirect drive inertial confinement fusion requires careful control of the X-ray drive symmetry throughout the laser pulse. When the outer cone beams strike the hohlraum wall, the plasma ablated off the hohlraum wall expands into the hohlraum and can alter both the outer and inner cone beam propagations and hence the X-ray drive symmetry especially at the final stage of the drive pulse. To quantitatively understand the wall motion, we developed a new experimental technique which visualizes the expansion and stagnation of the hohlraum wall plasma. Details of the experiment and the technique of spectrally selective x-ray imaging are discussed.

12.
Rev Sci Instrum ; 87(11): 11D612, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27910647

RESUMEN

We present a technique for determining the X-ray spectral quality from each region of an elliptically curved PET(002) crystal. The investigative technique utilizes the shape of the crystal rocking curve which changes significantly as the radius of curvature changes. This unique quality information enables the spectroscopist to verify where in the spectral range that the spectrometer performance is satisfactory and where there are regions that would show spectral distortion. A collection of rocking curve measurements for elliptically curved PET(002) has been built up in our X-ray laboratory. The multi-lamellar model from the XOP software has been used as a guide and corrections were applied to the model based upon measurements. But, the measurement of RI at small radius of curvature shows an anomalous behavior; the multi-lamellar model fails to show this behavior. The effect of this anomalous RI behavior on an X-ray spectrometer calibration is calculated. It is compared to the multi-lamellar model calculation which is completely inadequate for predicting RI for this range of curvature and spectral energies.

13.
Case Rep Infect Dis ; 2016: 6549268, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27774325

RESUMEN

We present a case of acute hemolytic anemia, renal failure, and Clostridium perfringens bacteremia in a patient with acute myelogenous leukemia. The high fatality of C. perfringens bacteremia requires that clinicians recognize and rapidly treat patients at risk for this infection. Although other hemolytic processes are in the differential diagnosis of these events, the presence of high fever, chills, and rapidly positive blood cultures may help narrow the diagnosis. Most cases of C. perfringens bacteremia have a concomitant coinfection, which makes broad spectrum empiric therapy essential. There is a high mortality rate of C. perfringens infections associated with leukemia.

14.
Phys Rev Lett ; 117(3): 035001, 2016 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-27472117

RESUMEN

First measurements of hydrodynamic growth near peak implosion velocity in an inertial confinement fusion (ICF) implosion at the National Ignition Facility were obtained using a self-radiographing technique and a preimposed Legendre mode 40, λ=140 µm, sinusoidal perturbation. These are the first measurements of the total growth at the most unstable mode from acceleration Rayleigh-Taylor achieved in any ICF experiment to date, showing growth of the areal density perturbation of ∼7000×. Measurements were made at convergences of ∼5 to ∼10× at both the waist and pole of the capsule, demonstrating simultaneous measurements of the growth factors from both lines of sight. The areal density growth factors are an order of magnitude larger than prior experimental measurements and differed by ∼2× between the waist and the pole, showing asymmetry in the measured growth factors. These new measurements significantly advance our ability to diagnose perturbations detrimental to ICF implosions, uniquely intersecting the change from an accelerating to decelerating shell, with multiple simultaneous angular views.

15.
Avian Dis ; 60(1): 43-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26953942

RESUMEN

Focal duodenal necrosis (FDN) is a poorly understood intestinal disease of egg layers, and has been associated with drops in egg production and decreased egg weights. The etiology of this disease is still unknown, but the condition has been associated with Clostridium colinum and Clostridium perfringens. In order to investigate the etiology, duodenal samples were taken from hens with FDN. The hens originated from table egg layer farms in three states. The samples were examined by histopathology, bacteriology, and immunohistochemistry. Macroscopically, all samples contained focal to multifocal, variably sized, reddened or brownish gray areas of mucosal erosion. Histopathology revealed mild to severe heterophilic and lymphoplasmacytic enteritis with loss of enterocytes at the villous tips, luminal fibrinonecrotic exudate, and variable numbers of Gram-positive and Gram-negative rod-shaped bacteria within the lesions in 16/30 samples. Clostridium perfringens was isolated by anaerobic bacteriology from 4/13 samples that had characteristic microscopic lesions of FDN. Polymerase chain reaction (PCR) revealed that all four isolates were Type A C. perfringens, positive for beta2 gene and negative for necrotic enteritis toxin B and enterotoxin genes. PCR for Clostridium colinum applied to DNA extracted from frozen intestinal samples yielded negative results in 14/14 duodenal samples. Immunohistochemistry (IHC) for 7C. perfringens, alpha and beta2 toxins stained a few to numerous long rod-shaped bacteria present in the lesions. IHC for alpha and beta2 toxins also stained enterocytes at the villous tips, inflammatory cells in the lamina propria, as well as degenerated and sloughed enterocytes present within the luminal exudate. These findings suggest that C. perfringens may play a role in the development of FDN. Experimental challenge studies with these isolates still need to be performed in order to reproduce the disease and fulfill Koch's postulates.


Asunto(s)
Pollos , Infecciones por Clostridium/veterinaria , Clostridium perfringens/genética , Enfermedades Intestinales/veterinaria , Necrosis/veterinaria , Enfermedades de las Aves de Corral/patología , Animales , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Proteínas de Unión al Calcio/genética , Proteínas de Unión al Calcio/metabolismo , Infecciones por Clostridium/microbiología , Infecciones por Clostridium/patología , Duodeno/microbiología , Duodeno/patología , Femenino , Enfermedades Intestinales/microbiología , Enfermedades Intestinales/patología , Necrosis/microbiología , Necrosis/patología , Enfermedades de las Aves de Corral/microbiología , Fosfolipasas de Tipo C/genética , Fosfolipasas de Tipo C/metabolismo , Estados Unidos
16.
Phys Rev Lett ; 114(14): 145004, 2015 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-25910132

RESUMEN

Experiments have recently been conducted at the National Ignition Facility utilizing inertial confinement fusion capsule ablators that are 175 and 165 µm in thickness, 10% and 15% thinner, respectively, than the nominal thickness capsule used throughout the high foot and most of the National Ignition Campaign. These three-shock, high-adiabat, high-foot implosions have demonstrated good performance, with higher velocity and better symmetry control at lower laser powers and energies than their nominal thickness ablator counterparts. Little to no hydrodynamic mix into the DT hot spot has been observed despite the higher velocities and reduced depth for possible instability feedthrough. Early results have shown good repeatability, with up to 1/2 the neutron yield coming from α-particle self-heating.

17.
Rev Sci Instrum ; 85(11): 11D502, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25430176

RESUMEN

1D spectral imaging was used to characterize the K-shell emission of Z ≈ 30-35 and Z ≈ 40-42 laser-irradiated foils at the National Ignition Facility. Foils were driven with up to 60 kJ of 3ω light, reaching laser irradiances on target between 0.5 and 20 × 10(15) W/cm(2). Laser-to-X-ray conversion efficiency (CE) into the Heα line (plus satellite emission) of 1.0%-1.5% and 0.15%-0.2% was measured for Z ≈ 30-32 and Z ≈ 40-42, respectively. Measured CE into Heα (plus satellite emission) of Br (Z = 35) compound foils (either KBr or RbBr) ranged between 0.16% and 0.29%. Measured spectra are compared with 1D non-local thermodynamic equilibrium atomic kinetic and radiation transport simulations, providing a fast and accurate predictive capability.

18.
Rev Sci Instrum ; 85(11): 11D613, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25430189

RESUMEN

The calibration campaign of the National Ignition Facility X-ray Spectrometer (NXS) was carried out at the Omega laser facility. Spherically symmetric, laser-driven, millimeter-scale x-ray sources of K-shell and L-shell emission from various mid-Z elements were designed for the 2-18 keV energy range of the NXS. The absolute spectral brightness was measured by two calibrated spectrometers. We compare the measured performance of the target design to radiation hydrodynamics simulations.

19.
Rev Sci Instrum ; 85(11): 11E503, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25430345

RESUMEN

Two-dimensional radiographs of imploding fusion capsules are obtained at the National Ignition Facility by projection through a pinhole array onto a time-gated framing camera. Parallax among images in the image array makes it possible to distinguish contributions from the capsule and from the backlighter, permitting correction of backlighter non-uniformities within the capsule radiograph. Furthermore, precise determination of the imaging system geometry and implosion velocity enables combination of multiple images to reduce signal-to-noise and discover new capsule features.

20.
Rev Sci Instrum ; 85(9): 093501, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25273720

RESUMEN

A very large area (7.5 mm(2)) laser-driven x-ray backlighter, termed the Big Area BackLighter (BABL) has been developed for the National Ignition Facility (NIF) to support high energy density experiments. The BABL provides an alternative to Pinhole-Apertured point-projection Backlighting (PABL) for a large field of view. This bypasses the challenges for PABL in the equatorial plane of the NIF target chamber where space is limited because of the unconverted laser light that threatens the diagnostic aperture, the backlighter foil, and the pinhole substrate. A transmission experiment using 132 kJ of NIF laser energy at a maximum intensity of 8.52 × 10(14) W/cm(2) illuminating the BABL demonstrated good conversion efficiency of >3.5% into K-shell emission producing ~4.6 kJ of high energy x rays, while yielding high contrast images with a highly uniform background that agree well with 2D simulated spectra and spatial profiles.

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