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Background The possibility of bloodstream infections caused by third-generation cephalosporin-resistant Enterobacterales (3GC-R-BSI) leads to a trade-off between empiric inappropriate treatment (IAT) and unnecessary carbapenem use (UCU). Accurately predicting 3GC-R-BSI could reduce IAT and UCU. We externally validate 2 previously derived prediction rules for community-onset (CO) and hospital-onset (HO) suspected bloodstream infections. Methods In 33 hospitals in 13 countries we prospectively enrolled 200 patients per hospital in whom blood cultures were obtained and intravenous antibiotics with coverage for Enterobacterales were empirically started. Cases were defined as 3GC-R-BSI or 3GC-R gram-negative infection (3GC-R-GNI) (analysis 2); all other outcomes served as a comparator. Model discrimination and calibration were assessed. Impact on carbapenem use was assessed at several cutoff points. Results 4650 CO infection episodes were included and the prevalence of 3GC-R-BSI was 2.1% (n = 97). IAT occurred in 69 of 97 (71.1%) 3GC-R-BSI and UCU in 398 of 4553 non–3GC-R-BSI patients (8.7%). Model calibration was good, and the AUC was.79 (95% CI,.75–.83) for 3GC-R-BSI. The prediction rule potentially reduced IAT to 62% (60/97) while keeping UCU comparable at 8.4% or could reduce UCU to 6.3% (287/4553) while keeping IAT equal. IAT and UCU in all 3GC-R-GNIs (analysis 2) improved at similar percentages. 1683 HO infection episodes were included and the prevalence of 3GC-R-BSI was 4.9% (n = 83). Here model calibration was insufficient. Conclusions A prediction rule for CO 3GC-R infection was validated in an international cohort and could improve empirical antibiotic use. Validation of the HO rule yielded suboptimal performance. [ABSTRACT FROM AUTHOR]

Textured transparent conductors are widely used in thin-film silicon solar cells. They lower the reflectivity at interfaces between different layers in the cell and/or cause an increase in the path length of photons in the Si absorber layer, which both result in an increase in the number of absorbed photons and, consequently, an increase in short-circuit current density (Jsc) and cell efficiency. Through optical simulations, we recently obtained strong indications that texturing of the transparent conductor in copper indium gallium (di-)selenide (CIGS) solar cells is also optically advantageous. Here, we experimentally demonstrate that the Jsc and efficiency of CIGS solar cells with an absorber layer thickness (dCIGS) of 0.85 μm, 1.00 μm and 2.00 μm increase through application of a moth-eye textured resist with a refractive index that is sufficiently similar to AZO (nresist = 1.792 vs. nAZO = 1.913 at 633 nm) to avoid large optical losses at the resist-AZO interface. On average, Jsc increases by 7.2%, which matches the average reduction in reflection of 7.0%. The average relative increase in efficiency is slightly lower (6.0%). No trend towards a larger relative increase in Jsc with decreasing dCIGS was observed. Ergo, the increase in Jsc can be fully explained by the reduction in reflection, and we did not observe any increase in Jsc based on an increased photon path length. [ABSTRACT FROM AUTHOR]

Abstract: This work presents an overview of recent results obtained in the field of III–V solar cell research as performed at the Radboud University Nijmegen. An n-type Al x Ga1− x InP2 window layer with x=1 was found to give the highest GaAs cell performance, in spite of a low doping carrier concentration as compared to GaInP2. As a result of the optimization of the GaAs cell structure obtained by metalorganic chemical vapor deposition (MOCVD) and subsequent processing, thin-film cells transferred from their native GaAs substrate to a foreign carrier, were achieved with a conversion efficiency of 24.5%. This is a world record for single-junction thin-film cells. Difficulties in the processing of thin-film GaInP2 cells, due to anomalous etching behavior of these layers in HCl, have been overcome by using a HBr/Br2/H2O mixture as an etchant. Thin-film GaInP2 cells with efficiencies up to 11.4% were obtained. [Copyright &y& Elsevier]

Abstract: Intrinsically carbon doped Al x Ga1− x As was grown by metalorganic chemical vapor deposition (MOCVD). The influence of the growth temperature, the V/III ratio and the aluminum fraction on the carbon, hydrogen, oxygen and aluminum incorporation was investigated over a wide parameter range. Secondary ion mass spectroscopy (SIMS) analysis was correlated with capacitance voltage (CV) measurements. It was found that a reduction of the growth temperature and the V/III ratio results in a strong decrease of the incorporated aluminum fraction in the layer, in particular in the range suitable for intrinsic carbon doping. This was explained by a lower decomposition rate of trimethyl aluminum compared to trimethyl gallium. For almost the entire investigated parameter range the carbon levels in the layer exceeded the carrier concentration due to deactivation by hydrogen and carbon incorporation on Ga-, Al- or interstitial sites. At a growth temperature of 530°C, however, all incorporated carbon is active, even at a maximal carrier concentration of 1.7×1020 cm−3. With the results obtained from this study, the carbon concentration and the aluminum fraction of intrinsic carbon doped layers can be controlled for a large range of growth conditions. [Copyright &y& Elsevier]

Intrinsic carbon doping of metalorganic chemical vapor deposition-grown (MOCVD–grown) AlxGa1-xAs was investigated under variation of the growth parameters aluminum fraction, growth temperature and V/III ratio. Growth was performed on 2° misoriented GaAs substrates, as commonly applied in industry. A linear increase of the hole concentration with increasing aluminum fraction was found. The dependence of the doping level on the V/III ratio showed an approximately constant level up to a V/III ratio of 2 and a decrease at higher V/III ratios. The trends observed were attributed to a decrease of hydrogenation by lower temperatures and by lower V/III ratios and the higher bond strength of Al–C compared to the Ga–C bond strength. A maximum hole concentration up to 1.25×1020cm-3 was found at a growth temperature of 530°C and a V/III ratio of 1. For the first time hole concentrations as high as 7.5×1019cm-3 were obtained at a normal growth temperature of 650°C. The last result shows that structures containing high intrinsically p-type doped AlxGa1-xAs layers can be grown at 650°C without the need for temperature variations. [Copyright &y& Elsevier]

The properties of crystalline films are strongly dependent on the morphology development during the first stages of growth, that is, the nucleation and growth of the first crystallites. The ideal method to investigate such films at atomic resolution is transmission electron microscopy (TEM). However, this technique usually requires extensive sample preparation. In this study we present a simple method to investigate thin film morphology with TEM. The key to this approach is the use of TEM membranes as growth substrates. As an illustration we describe fine grains of SnO2 deposited on these TEM membranes by atmospheric pressure chemical vapor deposition. [ABSTRACT FROM AUTHOR]

Abstract: Undoped tin oxide (SnO2) thin films have been deposited in a stagnant point flow chemical vapor deposition reactor from a water/tin tetrachloride mixture. By adding methanol during the deposition process the film electrical properties change significantly: ten times more conductive SnO2 films are obtained, with remarkably high mobility values of up to 55cm2/Vs. The investigations on the morphological and structural properties indicate that the main effect of methanol is the densification of the SnO2 films, which probably causes the improvement in the electrical properties. In all conditions the nucleation and coalescence phases take place very early in the growth. Below 10nm the films are already very conductive, which is very beneficial to applications that have strict requirements in terms of film transparency. [Copyright &y& Elsevier]

Abstract: Aluminum doped ZnO x (ZnO x :Al) films have been deposited on glass in an in-line industrial-type reactor by a metalorganic chemical vapor deposition process at atmospheric pressure. Tertiary-butanol has been used as oxidant for diethylzinc and trimethylaluminium as dopant gas. ZnO x :Al films can be grown at very high deposition rates of ∼14nm/s for a substrate speed from 150 to 500mm/min. The electrical, structural (crystallinity and morphology) and optical properties of the deposited films have been characterized by using Hall, four point probe, X-ray diffraction, atomic force microscope and spectrophotometer, respectively. All the films have c-axis, (002) preferential orientation and good crystalline quality. ZnO x :Al films are highly conductive (R<9Ω/sq, for a film thickness above 1300nm) and transparent in the visible range (>80%). These results show that ZnO x :Al films with good electrical and optical properties can be grown with a high throughput industrial CVD process at atmospheric pressure. First p–i–n a-Si:H solar cells have been deposited on this material, with initial efficiency approaching 8%. [Copyright &y& Elsevier]

Abstract: Aluminum doped zinc oxide films (ZnO x :Al) have been deposited on a moving glass substrate by a metalorganic CVD process at atmospheric pressure in an in-line industrial type reactor. Tertiary-butanol has been used as an oxidant for diethylzinc and trimethylaluminium as the dopant gas. The effect of the deposition temperature (from 380 to 540°C) on the deposition rate has been investigated by a numerical code, where a gas phase reaction among tertiary-butanol and diethylzinc is assumed to occur. The structural (crystallinity and morphology) properties of the films as a function of the deposition temperature have been analyzed by using X-ray diffraction and Scanning Electron Microscopy. A maximum growth rate of ∼11nm/s was found at a deposition temperature of 480°C, for which ZnOx:Al films show (002) preferential orientation, good crystalline quality and a naturally rough surface. ZnO x :Al films deposited at 480°C are also highly conductive (R<10Ω/□ for film thicknesses above 1050nm) and transparent (>85% in the visible range). These films have been used as front transparent conductive oxide layers in pin a-Si:H solar cells, achieving an initial efficiency approaching 8%. [Copyright &y& Elsevier]

In ultra-thin chalcopyrite solar cells and photovoltaic modules, efficient light management is required to increase the photocurrent and to gain in conversion efficiency. In this work we employ optical modelling to investigate different optical approaches and quantify their potential improvements in the short-circuit current density of Cu(In, Ga)Se 2 (CIGS) devices. For structures with an ultra-thin (500 nm) CIGS absorber, we study the improvements related to the introduction of (i) highly reflective metal back reflectors, (ii) internal nano-textures applied to the substrate and (iii) external micro-textures by using a light management foil. In the analysis we use CIGS devices in a PV module configuration, thus, solar cell structure including encapsulation and front glass. A thin Al 2 O 3 layer was considered in the structure at the rear side of CIGS for passivation and diffusion barrier for metal reflectors. We show that not any individual aforementioned approach is sufficient to compensate for the short circuit drop related to ultra-thin absorber, but a combination of a highly reflective back contact and textures (internal or external) is needed to obtain and also exceed the short-circuit current density of a thick (1800 nm) CIGS absorber. [ABSTRACT FROM AUTHOR]

Existing metabolomic clocks exhibit deficiencies in capturing the heterogeneous aging rates among individuals with the same chronological age. Yet, the modifiable and non-modifiable factors in metabolomic aging have not been systematically studied. Here, a new aging measure-MetaboAgeMort-is developed using metabolomic profiles from 239,291 UK Biobank participants for 10-year all-cause mortality prediction. The MetaboAgeMort showed significant associations with all-cause mortality, cause-specific mortality, and diverse incident diseases. Adding MetaboAgeMort to a conventional risk factors model improved the predictive ability of 10-year mortality. A total of 99 modifiable factors across seven categories are identified for MetaboAgeMort. Among these, 16 factors representing pulmonary function, body composition, socioeconomic status, dietary quality, smoking status, alcohol intake, and disease status showed quantitatively stronger associations. The genetic analyses revealed 99 genomic risk loci and 271 genes associated with MetaboAgeMort. The tissue-enrichment analysis showed significant enrichment in liver. While the external validation of the MetaboAgeMort is required, this study illuminates heterogeneous metabolomic aging across the same age, providing avenues for identifying high-risk individuals, developing anti-aging therapies, and personalizing interventions, thus promoting healthy aging and longevity., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)