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Funder: Green flexible hybrid perovskite solar module for the market: from smart lead manipulation to recycling; Grant(s): FLHYPER, 20201067, Defect‐mediated recombination losses limit the open‐circuit voltage (VOC) of perovskite solar cells (PSCs), negatively affecting the device's performance. Bulk and dimensional engineering have both been reported as promising strategies to passivate shallow defects, thus improving the photovoltaic conversion efficiency (PCE). Here, a combined bulk and surface treatment employing chlorine‐based compounds is employed. Methylammonium chloride (MACl) is used as a bulk additive, while 4‐methylphenethylammonium chloride (MePEACl) is deposited onto the perovskite surface to produce a low‐dimensional perovskite (LDP) and reduce nonradiative recombination. Through structural and morphological investigations, it can be confirmed that bulk and surface doping have a beneficial effect on the film morphology and its overall quality, while electroluminescence (EL) and photoluminescence (PL) analyses demonstrate an increased and more homogeneous emission. Applying this double passivation strategy in PSC fabrication, a boost is observed in both the short‐circuit current density and the VOC of the devices, achieving a champion 21.4% PCE while improving device stability.

BACKGROUND: Cryptococcal meningitis accounts for 15% of all AIDS-mortality globally. Most cases in low- and middle-income countries are treated with fluconazole monotherapy, which is associated with a high mortality. New available therapies are needed. Short course amphotericin B has been shown to be a safe and efficient therapeutic option. Sertraline has in vitro fungicidal activity against Cryptococcus and bi-directional synergy with fluconazole. METHODS: We conducted an open label clinical trial to assess the safety and efficacy of sertraline 400 mg/day and fluconazole 1200 mg/day (n=28) vs. sertraline, fluconazole and additional 5-days of amphotericin B deoxycholate 0.7-1 mg/kg (n=18) for cryptococcal meningitis. RESULTS: 2-week survival was 64% (18/28) without amphotericin and 89% (16/18) with amphotericin, and 10-week survival was 21% (6/28) vs. 61% (11/18), respectively (p=0.012). The cerebrospinal fluid (CSF) Cryptococcus clearance rate was 0.264 log(10) colony forming units (CFU)/mL of CSF/day (95%CI: 0.112-0.416) without amphotericin and 0.473 log(10) CFU/mL/day (95%CI: 0.344-0.60) with short-course amphotericin (p=0.03). Sertraline was discontinued in one participant due to side effects. Four participants receiving amphotericin B experienced hypokalemia

Objectives: Self-reported adherence assessment in HIV-infected patients on antiretroviral therapy (ART) is challenging and may overestimate adherence. The aim of this study was to improve the ability of health care providers to elicit patients’ reports of nonadherence using a “patient-centred” approach in a rural sub-Saharan African setting. Methods: A prospective interventional cohort study of HIV-infected patients on ART for ≥ 6 months attending an HIV clinic in rural Tanzania was carried out. The intervention consisted of a 2-day workshop for health care providers on patient-centred communication and the provision of an adherence assessment checklist for use in the consultations. Patients’ self-reports of nonadherence (≥ 1 missed ART dose/4 weeks), subtherapeutic plasma ART concentrations (< 2.5th percentile of published population-based pharmacokinetic models), and virological and immunological failure according to the World Health Organization definition were assessed before and after (1–3 and 6–9 months after) the intervention. Results: Before the intervention, only 3.3% of 299 patients included in the study reported nonadherence. Subtherapeutic plasma ART drug concentrations and virological and immunological failure were recorded in 6.5%, 7.7% and 14.5% of the patients, respectively. Two months after the intervention, health care providers detected significantly more patients reporting nonadherence compared with baseline (10.7 vs. 3.3%, respectively; P < 0.001), decreasing to 5.7% after 6–9 months. A time trend towards higher drug concentrations was observed for efavirenz but not for other drugs. The virological failure rate remained unchanged whereas the immunological failure rate decreased from 14.4 to 8.7% at the last visit (P = 0.002). Conclusions: Patient-centred communication can successfully be implemented with a simple intervention in rural Africa. It increases the likelihood of HIV-infected patients reporting problems with adherence to ART; however, sustainability remains a challenge.

Resonant tunnelling through two impurities has been observed in a vertical double-barrier GaAs/AlGaAs tunnelling diode. It manifests itself as a peak in the I-V characteristic near the conductance threshold. Analysis of the position of the current peak, its shape and the shift in magnetic field parallel to the current provides information about the characteristics of the two impurities. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

He + ion irradiation is an excellent tool to modify the magnitude and direction of the exchange bias field on the sub-micrometer scale without affecting the sample topography. This effect has been utilized to magnetically pattern NiFe/FeMn exchange bias double layers using resist masks patterned by electron beam lithography. Ion irradiation through the masks leads to a local modification of the magnetization reversal behavior and allows to study the magnetization reversal as a function of the exchange bias field strength and the pattern dimensions on a single sample. Results are presented on the macroscopic and microscopic magnetization reversal using the magneto-optic Kerr effect and Lorentz microscopy.

The paper develops a simple macroeconomic model which is then estimated for the Philippines. Econometric evidence shows that Philippines monetary authorities have been reluctant to allow a real devaluation, because of a large public external debt and for the fear of fueling inflation. Simulations show that, while an overvalued exchange rate may bring some benefits in the form of lower inflation and improved budgetary performance, its current account costs may be significant. Brady-like deals can reduce fiscal imbalances, limit the sensitivity of fiscal aggregates to the exchange rate, and increase the benefits of a more aggressive exchange rate policy.

It is generally agreed that the arrangements that have regulated trade in textiles and clothing have slowed the natural shift in comparative advantage from industrial countries to developing countries. But there is quite a bit of disagreement about how restrictive the Multi-Fibre Agreements (MFA) are. The authors address the potential sources of allocative inefficiency occasioned by the MFA and search for evidence that the MFA has indeed led to such inefficiency. In a theoretical section, they identify five sources of inefficiency relating to allocations across countries, across consumers, and among firms within constrained countries. In the empirical part of the paper, first they provide evidence of the restrictiveness of the quota arrangements from trends in import shares for aggregate categories of textiles and clothing, before and during the MFA. Then they provide evidence from a detailed examination of quota utilization rates and price differentials among EC importing countries. Among their findings: relatively high utilization rates across exporters suggest a relatively high degree (and stability) of quota bindingness across exporters; overshipment was highest for the most important (by shipment value) products; there is concentration among a few leading exports (China, Hong Kong, Taiwan, and Thailand) and a few importers (Benelux, Germany, and the United Kingdom); the data suggest a positive correlation between the coefficients of variation in prices and quota utilization rates for China, Hong Kong, and Korea suggesting that prices are related, as one would expect, to the degree of bindingness; and the data suggest that binding quotas would be associated with higher import prices.

Three new diterpenes were isolated from the aerial part of Haplopappus chrysanthemifolius and assigned the structures 6α-hydroxy-ent-labd-8(17)-en-15-oic acid, 3β-acetoxy-ent-labd-8(17)-en-15-oic acid and 18α-acetoxylabd-8(17)-en-15-oic acid. The structures were elucidated by high field NMR spectroscopy.

A bioassay-guided chemical study of a methanolic extract of fresh leaves of Luma chequen led to the isolation of lumaflavanones A (1), B (2) and C (3) whose structures are proposed on the basis of NMR spectroscopic data. The structure of lumaflavanone A was confirmed by X-ray analysis. Antifeedant (Spodoptera littoralis), brine shrimp (Artemia salina) and fungistatic (Botrytis cinerea) bioassays showed that while 3 was the most active in the first two assays the mixture of 1 and 2 was more effective as a fungistatic.