Zinc oxide (ZnO), with its excellent luminescent properties and the ease of growth of its nanostructures, holds promise for the development of photonic devices. The recent advances in growth of ZnO nanorods are discussed. Results from both low temperature and high temperature growth approaches are presented. The techniques which are presented include metal-organic chemical vapour deposition (MOCVD), vapour phase epitaxy (VPE), pulse laser deposition (PLD), vapour-liquid-solid (VLS), aqueous chemical growth (ACG) and finally the electrodeposition technique as an example of a selective growth approach. Results from structural as well as optical properties of a variety of ZnO nanorods are shown and analysed using different techniques, including high resolution transmission electron microscopy (HR-TEM), scanning electron microscopy (SEM), photoluminescence (PL) and cathodoluminescence (CL), for both room temperature and for low temperature performance. These results indicate that the grown ZnO nanorods possess reproducible and interesting optical properties. Results on obtaining p-type doping in ZnO micro- and nanorods are also demonstrated using PLD. Three independent indications were found for p-type conducting, phosphorus-doped ZnO nanorods: first, acceptor-related CL peaks, second, opposite transfer characteristics of back-gate field effect transistors using undoped and phosphorus doped wire channels, and finally, rectifying I-V characteristics of ZnO:P nanowire/ZnO:Ga p-n junctions. Then light emitting diodes (LEDs) based on n-ZnO nanorods combined with different technologies (hybrid technologies) are suggested and the recent electrical, as well as electro-optical, characteristics of these LEDs are shown and discussed. The hybrid LEDs reviewed and discussed here are mainly presented for two groups: those based on n-ZnO nanorods and p-type crystalline substrates, and those based on n-ZnO nanorods and p-type amorphous substrates. Promising electroluminescence characteristics aimed at the development of white LEDs are demonstrated. Although some of the presented LEDs show visible emission for applied biases in excess of 10 V, optimized structures are expected to provide the same emission at much lower voltage. Finally, lasing from ZnO nanorods is briefly reviewed. An example of a recent whispering gallery mode (WGM) lasing from ZnO is demonstrated as a way to enhance the stimulated emission from small size structures.

Background Although advanced medical imaging technologies give detailed diagnostic information, a low-dose, fast, and inexpensive option for early detection of respiratory diseases and follow-ups is still lacking. The novel method of x-ray dark-field chest imaging might fill this gap but has not yet been studied in living humans. Enabling the assessment of microstructural changes in lung parenchyma, this technique presents a more sensitive alternative to conventional chest x-rays, and yet requires only a fraction of the dose applied in CT. We studied the application of this technique to assess pulmonary emphysema in patients with chronic obstructive pulmonary disease (COPD). MethodsIn this diagnostic accuracy study, we designed and built a novel dark-field chest x-ray system (Technical University of Munich, Munich, Germany)-which is also capable of simultaneously acquiring a conventional thorax radiograph ( 7s, 0•035 mSv effective dose). Patients who had undergone a medically indicated chest CT were recruited from the department of Radiology and Pneumology of our site (Klinikum rechts der Isar, Technical University of Munich, Munich, Germany). Patients with pulmonary pathologies, or conditions other than COPD, that might influence lung parenchyma were excluded. For patients with different disease stages of pulmonary emphysema, x-ray dark-field images and CT images were acquired and visually assessed by five readers. Pulmonary function tests (spirometry and body plethysmography) were performed for every patient and for a subgroup of patients the measurement of diffusion capacity was performed. Individual patient datasets were statistically evaluated using correlation testing, rank-based analysis of variance, and pair-wise post-hoc comparison. Findings Between October, 2018 and December, 2019 we enrolled 77 patients. Compared with CT-based parameters (quantitative emphysema ρ=-0•27, p=0•089 and visual emphysema ρ=-0•45, p=0•0028), the dark-field signal (ρ=0•62, p<0•0001) yields a stronger correlation with lung diffusion capacity in the evaluated cohort. Emphysema assessment based on dark-field chest x-ray features yields consistent conclusions with findings from visual CT image interpretation and shows improved diagnostic performance than conventional clinical tests characterising emphysema. Pair-wise comparison of corresponding test parameters between adjacent visual emphysema severity groups (CT-based, reference standard) showed higher effect sizes. The mean effect size over the group comparisons (absent-trace, trace-mild, mild-moderate, and moderate-confluent or advanced destructive visual emphysema grades) for the COPD assessment test score is 0•21, for forced expiratory volume in 1 s (FEV 1 )/functional vital capacity is 0•25, for FEV 1 % of predicted is 0•23, for residual volume % of predicted is 0•24, for CT emphysema index is 0•35, for dark-field signal homogeneity within lungs is 0•38, for dark-field signal texture within lungs is 0•38, and for darkfield-based emphysema severity is 0•42. Interpretation X-r...

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Summary Idiopathic pulmonary fibrosis (IPF) is a frequent indication for lung transplantation (LTX) with pulmonary hypertension (PH) negatively affecting outcome. The optimal procedure type remains a debated topic. The aim of this study was to evaluate the impact of pretransplant PH in IPF patients. Single LTX (SLTX, n = 46) was the standard procedure type. Double LTX (DLTX, n = 30) was only performed in cases of relevant PH or additional suppurative lung disease. There was no significant difference for pretransplant clinical parameters. Preoperative mean pulmonary arterial pressure was significantly higher in DLTX recipients (22.7 ± 0.8 mmHg vs. 35.9 ± 1.8 mmHg, P < 0.001). After transplantation, 6‐min‐walk distance and BEST‐FEV1 were significantly higher for DLTX patients (6‐MWD: 410 ± 25 m vs. 498 ± 23 m, P = 0.02; BEST‐FEV1: 71.2 ± 3.0 (% pred) vs. 86.2 ± 4.2 (% pred), P = 0.004). Double LTX recipients demonstrated a significantly better 1‐year‐, overall‐ and Bronchiolitis obliterans Syndrome (BOS)‐free survival (P < 0.05). Cox regression analysis confirmed SLTX to be a significant predictor for death and BOS. Single LTX offers acceptable survival rates for IPF patients. Double LTX provides a significant benefit in selected recipients. Our data warrant further trials of SLTX versus DLTX stratifying for potential confounders including PH.

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Posaconazole is an extended-spectrum triazole antifungal used in the treatment and prophylaxis of Aspergillus infections. It is available as oral suspension (POS-Liq) and delayed-release tablets (POS-Tab). The aim of this longitudinal, retrospective study was to compare the clinical effectiveness, toxicity and pharmacokinetics of POS-Liq vs POS-Tab in lung transplant recipients (LTx-recipients), who were treated with both formulations subsequently. Twenty-four consecutive LTx-recipients with 191 documented posaconazole trough levels (PTLs) for POS-Liq or POS-Tab were included. The administered daily doses were 300 mg for POS-Tab and 600 mg (prophylaxis) or 800 mg (therapy) for POS-Liq. Target PTLs were ≥700 ng/mL (prophylaxis) and ≥1250 ng/mL (therapy). The overall prophylactic and therapeutic response rates were 78% and 67%, respectively. No cases of hepatotoxicity or QT-prolongation were observed with either formulation. The achieved target PTLs were tripled under POS-Tab compared to POS-Liq with fewer risk factors for sub-therapeutic PTLs. Concomitant administration of POS-Tab significantly reduced the tacrolimus concentration-to-dose ratio (P = .001). We suggest the use of POS-Tab is appropriate for prophylaxis and therapy of Aspergillus infections in LTx-recipients, since POS-Tab displayed more reliable PTLs with no added adverse events. However, we recommend regular drug monitoring for POS-Liq and for therapy with POS-Tab and that immunosuppressant levels are monitored closely when the posaconazole formulation is switched.

The room-temperature optical pseudo-dielectric-functions of single-phase, single-crystalline rocksalt-structure MgxZn1−xO with Mg-content x between 0.68 and 1 were determined in the photon energy range from 0.75to9.10eV using spectroscopic ellipsometry. The refractive index determined in the spectral region below the fundamental absorption edge decreases with increasing Mg content. The pseudo-dielectric-functions reveal structures caused in critical points due to electronic band-to-band transitions and free exciton formation at the fundamental band-gap transition. Standard model dielectric function approaches were applied for line shape analysis. Upon increase of the bond ionicity with increasing Mg content the energies of the band-to-band transitions as well as the fundamental-band-gap exciton binding energy parameters increase, while the Γ-point spin-orbit-splitting energy parameter decreases. We compare our results with the band-gap properties of wurtzite-structure MgxZn1−xO with Mg-content x between 0 and 0.5 obtained previously, and we discuss discontinuities across the phase transition. We provide estimates for the band gap bowing parameter of rocksalt-structure MgxZn1−xO and the band-gap value of rocksalt-structure ZnO.