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1.
Eur J Pain ; 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38623029

RESUMEN

BACKGROUND AND OBJECTIVE: Recently, a consensus process specified a core outcome set (COS) of domains to be assessed in each comparative effectiveness research and clinical practice related to acute postoperative pain. Physical function (PF) was one of these domains. The aim of this review was to investigate which patient-reported outcome measures (PROMs) are used to assess PF after total knee arthroplasty (TKA) in clinical trials and if they fulfil basic requirements for a COS of PROMs based on their psychometric properties. METHODS: A systematic review of randomized controlled trials and observational studies based on a search in MEDLINE, EMBASE and CENTRAL was undertaken. PROMs and performance measures were extracted and investigated, including evaluation of psychometric properties of PROMs based on COSMIN recommendations. RESULTS: From initially 2896 identified records, 479 studies were included in the qualitative synthesis. Only 87 of these trials (18%) assessed PF using PROMs, whereas especially performance outcome measures were used in 470 studies (98%). Application of the 'COSMIN Risk-of-Bias-Box 1' to 13 of the 14 identified PROMs resulted in insufficient content validity of the included PROMs regarding the target population based on the inauguration or development articles. CONCLUSION: Our data indicate that a patient-centred postoperative assessment of PF in pain-related clinical trials early after TKA is not common, even though patient-reported assessment is widely recommended. In addition, none of the applied PROMs shows content validity based on their inauguration or development articles for the assessment of postoperative pain-related PF after TKA. SIGNIFICANCE: A systematic search for patient-reported outcome measures assessing postoperative, pain-related physical function after total knee arthroplasty in clinical trials and assessment of their content validity revealed none that fulfilled requirements based on COSMIN recommendations.

2.
Opt Express ; 32(5): 7473-7483, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38439426

RESUMEN

We present a full performance characterization of a solid state pulse picker for hard x-ray pulses at synchrotrons. The device is called WaveGate. Specifically, we quantify its efficiency (>30 %), timing capabilities (switching times between 100 ns and ms), on-off contrast (>104) and influence on the coherence properties of the incident x-ray beam. In addition, we discuss the implementation of the WaveGate in an optical pump - x-ray probe setup. Even if single pulse selection is performed by external detector gating, the WaveGate drastically increases the efficiency of a measurement. Finally, we introduce advanced timing schemes that can be realized by modulating the time structure of the synchrotron beam.

3.
HIV Med ; 25(4): 498-503, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38072823

RESUMEN

OBJECTIVE: We aimed to identify spatial clusters of high HIV prevalence in Germany. METHODS: Using nationwide outpatient claims data comprising information of about 88% of the total German population (N = 72 041 683), we examined spatial variations and spatial clusters of high HIV prevalence at the district level (N = 401). People with HIV were identified using the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10 codes) B20, B22, and B24 (HIV disease) documented as 'confirmed'. RESULTS: Among 72 041 683 people with statutory health insurance in Germany in 2021, 72 636 had diagnosed HIV, which corresponds to a prevalence of 101 per 100 000 individuals (0.10%). Of these, 56 895 were males (78%). At a district level, the HIV prevalence varied by a factor of 32 between 13 in a rural district in Bavaria and 417 per 100 000 individuals in the German capital, Berlin. The spatial autocorrelation coefficient was 0.24 (p < 0.0001, Global Moran's I). Several high-prevalence spatial clusters of different sizes were identified, mostly located in western Germany. The largest cluster comprised eight districts in the southern part of Hesse, including the city of Frankfurt and the city of Mainz in Rhineland-Palatinate. The second cluster consisted of four districts in North Rhine-Westphalia, including the cities of Cologne and Düsseldorf. Two districts in southern Germany (Mannheim and Ludwigshafen) formed the third cluster. Only urban districts were observed in spatial clusters of high HIV prevalence. CONCLUSIONS: The current study identified for the first time spatial clusters with high HIV prevalence in Germany. This understanding is of particular importance when planning the general and specialized medical care of patients with HIV and to support preventive measures.


Asunto(s)
Infecciones por VIH , Masculino , Humanos , Femenino , Infecciones por VIH/epidemiología , Análisis Espacial , Pacientes Ambulatorios , Alemania/epidemiología , Prevalencia
4.
Eur J Cardiovasc Nurs ; 23(2): e20, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-37676742
5.
HIV Med ; 25(2): 201-211, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37786263

RESUMEN

OBJECTIVES: Viral hepatitis co-infection among people living with HIV is known to accelerate the progression of liver disease and AIDS. An increased prevalence and incidence of hepatitis B virus (HBV) infection among people living with HIV demands continuous monitoring to adapt targeted prevention strategies to reach the global goals of eliminating viral hepatitis as a public health threat. METHODS: We determined the prevalence and incidence of HBV for the years 1996-2019 from yearly blood sample testing and questionnaire reports among people living with HIV belonging to a nationwide, multicentre observational, prospective cohort study. RESULTS: Among this study population of 3479 participants, the majority (87%) indicated that being men who have sex with men (MSM) was their likely HIV transmission route; 51% were recruited from Berlin. HBV prevalence for acute/chronic and resolved infections decreased from 4.1% and 45% in 1996-1999 to 1.3% and 16% in 2019, respectively. Simultaneously, participants with a serological status indicating HBV vaccination increased from 25% in 1996-1999 to 69% in 2019. Among vaccinated participants with relevant information (n = 1135), 38% received their first HBV vaccination after HIV infection. The HBV incidence rate in 565 eligible participants decreased from 6.9/100 person-years in 2004-2007 to 0.45/100 person-years in 2015. CONCLUSION: Increasing vaccination coverage because of a general HBV vaccination recommendation and catch-up vaccination efforts among risk groups decreased HBV infection prevalence over time among this study population of people living with HIV, primarily MSM and from Berlin. Despite this success, the prevalence and incidence of HBV remains higher than in the general population in Germany. This emphasizes the need for continued HBV prevention by promoting HBV vaccination and HBV screening at regular intervals based on the individual risk behaviour.


Asunto(s)
Coinfección , Infecciones por VIH , Seropositividad para VIH , VIH-1 , Hepatitis B , Minorías Sexuales y de Género , Masculino , Humanos , Femenino , Homosexualidad Masculina , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Infecciones por VIH/diagnóstico , Estudios de Cohortes , Estudios Prospectivos , Prevalencia , Cobertura de Vacunación , Coinfección/epidemiología , Hepatitis B/epidemiología , Hepatitis B/prevención & control , Virus de la Hepatitis B , Vacunación
6.
Phys Rev Lett ; 130(17): 173001, 2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37172243

RESUMEN

To test bound-state quantum electrodynamics (BSQED) in the strong-field regime, we have performed high precision x-ray spectroscopy of the 5g-4f and 5f- 4d transitions (BSQED contribution of 2.4 and 5.2 eV, respectively) of muonic neon atoms in the low-pressure gas phase without bound electrons. Muonic atoms have been recently proposed as an alternative to few-electron high-Z ions for BSQED tests by focusing on circular Rydberg states where nuclear contributions are negligibly small. We determined the 5g_{9/2}- 4f_{7/2} transition energy to be 6297.08±0.04(stat)±0.13(syst) eV using superconducting transition-edge sensor microcalorimeters (5.2-5.5 eV FWHM resolution), which agrees well with the most advanced BSQED theoretical prediction of 6297.26 eV.

7.
Ann Nucl Med ; 36(7): 623-633, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35534690

RESUMEN

AIM: In the CheckRad-CD8 trial patients with locally advanced head and neck squamous cell cancer are treated with a single cycle of induction chemo-immunotherapy (ICIT). Patients with pathological complete response (pCR) in the re-biopsy enter radioimmunotherapy. Our goal was to study the value of F-18-FDG PET/CT in the prediction of pCR after induction therapy. METHODS: Patients treated within the CheckRad-CD8 trial that additionally received FDG- PET/CT imaging at the following two time points were included: 3-14 days before (pre-ICIT) and 21-28 days after (post-ICIT) receiving ICIT. Tracer uptake in primary tumors (PT) and suspicious cervical lymph nodes (LN +) was measured using different quantitative parameters on EANM Research Ltd (EARL) accredited PET reconstructions. In addition, mean FDG uptake levels in lymphatic and hematopoietic organs were examined. Percent decrease (Δ) in FDG uptake was calculated for all parameters. Biopsy of the PT post-ICIT acquired after FDG-PET/CT served as reference. The cohort was divided in patients with pCR and residual tumor (ReTu). RESULTS: Thirty-one patients were included. In ROC analysis, ΔSUVmax PT performed best (AUC = 0.89) in predicting pCR (n = 17), with a decline of at least 60% (sensitivity, 0.77; specificity, 0.93). Residual SUVmax PT post-ICIT performed best in predicting ReTu (n = 14), at a cutpoint of 6.0 (AUC = 0.91; sensitivity, 0.86; specificity, 0.88). Combining two quantitative parameters (ΔSUVmax ≥ 50% and SUVmax PT post-ICIT ≤ 6.0) conferred a sensitivity of 0.81 and a specificity of 0.93 for determining pCR. Background activity in lymphatic organs or uptake in suspected cervical lymph node metastases lacked significant predictive value. CONCLUSION: FDG-PET/CT can identify patients with pCR after ICIT via residual FDG uptake levels in primary tumors and the related changes compared to baseline. FDG-uptake in LN + had no predictive value. TRIAL REGISTRY: ClinicalTrials.gov identifier: NCT03426657.


Asunto(s)
Fluorodesoxiglucosa F18 , Neoplasias de Cabeza y Cuello , Linfocitos T CD8-positivos , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/terapia , Humanos , Inmunoterapia , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Radiofármacos
8.
Vision Res ; 193: 107994, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34979298

RESUMEN

The neural response in the human visual system is composed of magno-, parvo- and koniocellular input from the retina. Signal differences from functional imaging between health and individuals with a cognitive weakness are attributed to a dysfunction of a specific retinal input. Yet, anatomical interconnections within the human visual system obscure individual contribution to the neural response in V1. Deflections in the visual evoked potential (VEP) arise from an interaction between electric dipoles, their strength determined by the size of the neural population active during temporal - and spatial luminance contrast processing. To investigate interaction between these neural responses, we recorded the VEP over visual cortex of 14 healthy adults viewing four series of windmill patterns. Within a series, the relative area white in a pattern varied systematically. Between series, the number of sectors across which this area was distributed doubled. These patterns were viewed as pattern alternating and on-/off stimuli. P100/P1 amplitude increased linearly with the relative area white in the pattern, while N135/N1 and P240/P2 amplitude increased with the number of sectors of which the area white was distributed. The decreases P100 amplitude with increasing number of sectors is attributed to an interaction between electric dipoles located in granular and supragranular layers of V1. Differences between the VEP components obtained during a pattern reversing display and following pattern onset are accounted for by the transient and sustained nature of neural responses processing temporal - and spatial luminance contrast and ability of these responses to manifest in the VEP.


Asunto(s)
Oftalmopatías , Corteza Visual , Adulto , Potenciales Evocados Visuales , Humanos , Estimulación Luminosa/métodos , Retina/fisiología , Corteza Visual/fisiología
9.
Metrologia ; 58(1)2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34354301

RESUMEN

We use an array of transition-edge sensors, cryogenic microcalorimeters with 4 eV energy resolution, to measure L x-ray emission-line profiles of four elements of the lanthanide series: praseodymium, neodymium, terbium, and holmium. The spectrometer also surveys numerous x-ray standards in order to establish an absolute-energy calibration traceable to the international system of units for the energy range 4 keV to 10 keV. The new results include emission line profiles for 97 lines, each expressed as a sum of one or more Voigt functions; improved absolute energy uncertainty on 71 of these lines relative to existing reference data; a median uncertainty on the peak energy of 0.24 eV, four to ten times better than the median of prior work; and six lines that lack any measured values in existing reference tables. The 97 lines comprise nearly all of the most intense L lines from these elements under broad-band x-ray excitation. The work improves on previous measurements made with a similar cryogenic spectrometer by the use of sensors with better linearity in the absorbed energy and a gold x-ray absorbing layer that has a Gaussian energy-response function. It also employs a novel sample holder that enables rapid switching between science targets and calibration targets with excellent gain balancing. Most of the results for peak energy values shown here should be considered as replacements for the currently tabulated standard reference values, while the line shapes given here represent a significant expansion of the scope of available reference data.

10.
Phys Rev Lett ; 127(5): 053001, 2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-34397250

RESUMEN

We observed electronic K x rays emitted from muonic iron atoms using superconducting transition-edge sensor microcalorimeters. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic Kα and Kß x rays together with the hypersatellite K^{h}α x rays around 6 keV. This signature reflects the time-dependent screening of the nuclear charge by the negative muon and the L-shell electrons, accompanied by electron side feeding. Assisted by a simulation, these data clearly reveal the electronic K- and L-shell hole production and their temporal evolution on the 10-20 fs scale during the muon cascade process.

11.
J Synchrotron Radiat ; 28(Pt 2): 375-382, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33650548

RESUMEN

A new concept for temporal gating of synchrotron X-ray pulses based on laser-induced thermal transient gratings is presented. First experimental tests of the concept yield a diffraction efficiency of 0.18%; however, the calculations indicate a theoretical efficiency and contrast of >30% and 10-5, respectively. The full efficiency of the pulse picker has not been reached yet due to a long-range thermal deformation of the sample after absorption of the excitation laser. This method can be implemented in a broad spectral range (100 eV to 20 keV) and is only minimally invasive to an existing setup.

12.
Appl Radiat Isot ; 172: 109693, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33774323

RESUMEN

225Ac is a valuable medical radionuclide for targeted α therapy, but 227Ac is an undesirable byproduct of an accelerator-based synthesis method under investigation. Sufficient detector sensitivity is critical for quantifying the trace impurity of 227Ac, with the 227Ac/225Ac activity ratio predicted to be approximately 0.15% by end-of-bombardment (EOB). Superconducting transition edge sensor (TES) microcalorimeters offer high resolution energy spectroscopy using the normal-to-superconducting phase transition to measure small changes in temperature. By embedding 225Ac production samples in a gold foil thermally coupled to a TES microcalorimeter we can measure the decay energies of the radionuclides embedded with high resolution and 100% detection efficiency. This technique, known as decay energy spectroscopy (DES), collapses several peaks from α decays into single Q-value peaks. In practice there are more complex factors in the interpretation of data using DES, which we will discuss herein. Using this technique we measured the EOB 227Ac impurity to be (0.142 ± 0.005)% for a single production sample. This demonstration has shown that DES is a useful tool for quantitative measurements of complicated spectra.


Asunto(s)
Actinio/química , Análisis Espectral/métodos , Calorimetría/métodos , Temperatura
14.
Phys Rev E ; 102(4-1): 043212, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33212701

RESUMEN

In this work, we present results from experiments capable of producing and measuring the propagation of multiple successive, copropagating shocks across an unstable planar interface, where the shocks are independently driven and separately controllable, enabling the study of this important phenomenon. Copropagating shocks play a significant role in a wide range of systems involving stratified media subject to a shock, and exhibit different physical characteristics compared to counterpropagating shocks. Existing techniques, however, preclude copropagating shocks, so experiments to date have been limited to the study of counterpropagating shocks. We address this previous limitation and open a physical parameter space for study using a new hohlraum platform on the National Ignition Facility. Initial experimental results are presented together with comparisons from numerical simulations.

15.
Epidemiol Mikrobiol Imunol ; 69(2): 57-63, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32819104

RESUMEN

OBJECTIVES: Intra-abdominal candidiasis (IAC) is an invasive fungal infection representing the most common type of invasive Candida infection in surgical intensive care units (ICUs). Recently, decreased antifungal susceptibility and progressive shift in the aetiology of invasive candidiasis has been observed worldwide. We explored IAC epidemiology in surgical ICU. MATERIAL AND METHODS: We retrospectively reviewed the records of 64 patients with IAC admitted at our surgical ICU over a 4-year period (2013-2016). IAC incidence, microbiological results, antifungal therapy, and mortality were analysed. RESULTS: The cumulative IAC incidence was 18.4 cases per 1000 admissions (2013: 12.6; 2014: 17.7; 2015: 16.8; 2016: 24.5), including hospital-acquired IAC incidence (2013: 9.8; 2014: 13.3; 2015 10.1; 2016: 13.3) and community-acquired IAC incidence (2013: 2.8; 2014: 4.4; 2015: 6.7; 2016: 11.2). Candida albicans represented the most common species (n = 35, 50.0%) followed by Candida glabrata (n = 15, 21.4%), Candida tropicalis (n = 6, 8.6%) and other yeasts (each < 5.0%). Incidence rate of C. albicans (2013: 7(78%); 2014: 10(59%); 2015: 6(35%); 2016: 12(44%)) and incidence rate of C. non-albicans (2013: 2(22%); 2014: 7(41%); 2015: 9(53%); 2016: 14(52%)) were different in trend. All fungal isolates were susceptible to echinocandins, amphotericin B and voriconazole. Regarding fluconazole susceptibility, C. krusei (n = 3) was resistant and C. glabrata (n = 9) was susceptible-dose dependent (SDD). The ratio of SDD C. glabrata isolates to all isolated C. glabrata strains was 9/15 (60%) (2013: 0/2; 2014: 0/2; 2015: 1/3; 2016: 8/8). Decreased fluconazole susceptibility for C. glabrata isolates was reported in both community-acquired IAC (n = 3) and hospital-acquired IAC (n = 6). Overall 30-day mortality rate was 25.0% (16/64). CONCLUSIONS: We have revealed slowly raising of overall IAC incidence, more increasing trend in incidence of community-acquired IAC compared to rather steady incidence of hospital-acquired IAC. During period 2013-2016 we have observed a significant shift in the aetiology of IAC towards an increased proportion of non-albicans Candida species, particularly C. glabrata. Acquired decreased fluconazole susceptibility was related to C. glabrata isolates exclusively. Emergence of decreased antifungal susceptibility has been preceded by increase of non-albicans Candida isolates.


Asunto(s)
Unidades de Cuidados Intensivos , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Candida/efectos de los fármacos , Cuidados Críticos , Farmacorresistencia Fúngica/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Estudios Retrospectivos
17.
Phys Rev Lett ; 124(18): 185003, 2020 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-32441981

RESUMEN

Rayleigh-Taylor instability growth is shown to be hydrodynamically scale invariant in convergent cylindrical implosions for targets that varied in radial dimension and implosion timescale by a factor of 3. The targets were driven directly by laser irradiation providing a short impulse, and instability growth at an embedded aluminum interface occurs as it converges radially inward by a factor of 2.25 and decelerates on a central foam core. Late-time growth factors of 14 are observed for a single-mode m=20 azimuthal perturbation at both scales, despite the differences in laser drive conditions between the experimental facilities, consistent with predictions from radiation-hydrodynamics simulations. This platform enables detailed investigations into the limits of hydrodynamic scaling in high-energy-density systems.

18.
Phys Rev Lett ; 124(15): 159901, 2020 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-32357038

RESUMEN

This corrects the article DOI: 10.1103/PhysRevLett.120.025002.

19.
Nat Commun ; 11(1): 544, 2020 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-31992703

RESUMEN

The injection and mixing of contaminant mass into the fuel in inertial confinement fusion (ICF) implosions is a primary factor preventing ignition. ICF experiments have recently achieved an alpha-heating regime, in which fusion self-heating is the dominant source of yield, by reducing the susceptibility of implosions to instabilities that inject this mass. We report the results of unique separated reactants implosion experiments studying pre-mixed contaminant as well as detailed high-resolution three-dimensional simulations that are in good agreement with experiments. At conditions relevant to mixing regions in high-yield implosions, we observe persistent chunks of contaminant that do not achieve thermal equilibrium with the fuel throughout the burn phase. The assumption of thermal equilibrium is made in nearly all computational ICF modeling and methods used to infer levels of contaminant from experiments. We estimate that these methods may underestimate the amount of contaminant by a factor of two or more.

20.
J Chem Phys ; 152(3): 034107, 2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-31968968

RESUMEN

To elucidate the effect of the architecture of supported bimetallic nanocatalysts, we developed a new lattice kinetic Monte Carlo based on the classifying and counting adsorption sites with respect to their generalized coordination number. We employed this tool to estimate the activity of MgO-supported PtNi nanoalloys for oxygen reduction. We demonstrated that the presence of Ni atoms in contact with the substrate massively enhances their activity with at least a 7-order of magnitude increase in the turnover of water production with respect to the case where only Pt lay at the interface. We further discussed how the nanoalloy shape affects the activity showing that truncated octahedra are 102 more active than cuboctahedra of similar size. We explained our results in terms of their distinct distribution and occurrence of the most active sites for oxygen reduction leading to the stabilization of different chemical species during the reaction dynamics. Our results suggest that engineering multifaceted and long edge PtNi-nanoalloys with a certain chemical ordering at the support interface would improve their catalytic performance for the oxygen reduction reaction.

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