Assessing the suitability of copper thiocyanate as a hole-transport layer in inverted CsSnI3 perovskite photovoltaics

We report the fndings of a study into the suitability of copper (I) thiocyanate (CuSCN) as a hole-transport layer in inverted photovoltaic (PV) devices based on the black gamma phase (B-γ) of CsSnl3 perovskite. Remarkably, when B-γ-CsSnI3 perovskite is deposited from a dimethylformamide solution onto a 180–190nm thick CuSCN flm supported on an indium-tin oxide (ITO) electrode, the CuSCN layer is completely displaced leaving a perovskite layer with high uniformity and coverage of the underlying ITO electrode. This fnding is confrmed by detailed analysis of the thickness and composition of the film that remains after perovskite deposition, together with photovoltaic device studies. The results of this study show that, whilst CuSCN has proved to be an excellent hole-extraction layer for high performance lead-perovskite and organic photovoltaics, it is unsuitable as a hole-transport layer in inverted B-γCsSnI3 perovskite photovoltaics processed from solution

Perceptions of complementary/alternative medicine use and influence on evidence-based asthma medicine adherence in Malaysian children

Abstract Complementary and alternative medicine (CAM) is widely used especially in Asia including for childhood asthma. The use of CAM could influence adherence to evidence-based (E-B) medicine. We explored the views of carers of Malaysian children with asthma regarding the use of CAM for childhood asthma, and its relationship with self-reported adherence to E-B medicine. We used a screening questionnaire to identify children diagnosed with asthma from seven suburban primary schools in Malaysia. Informed consent was obtained prior to the interviews. We conducted the interviews using a semi-structured topic guide in participants’ preferred language (Malay, Mandarin, or Tamil). All interviews were audio-recorded, transcribed verbatim and coded using Nvivo. Analysis was performed thematically, informed by the Necessity-Concerns Framework. A total of 46 carers (16 Malays, 21 Indians, 9 Chinese) contributed to 12 focus groups and one individual interview. We categorised participants’ as ‘Non-CAM’; ‘CAM’; or ‘combination’ user. Cultural practices and beliefs in the efficacy of CAM resulted in widespread use of CAM. Most carers used CAM as ‘complementary’ to E-B medicine. Concerns about dependence on or side effects of E-B treatment influenced carers’ decisions to rely on CAM as an ‘alternative’, with an important minority of accounts describing potentially harmful CAM-use. Healthcare professionals should discuss beliefs about the necessity for and concerns about use of both E-B medicine and CAM, and provide balanced information about effectiveness and safety. The aim is to improve adherence to regular E-B preventer medication and prevent delays in seeking medical advice and harmful practices associated with CAM

The INTOXICATE study: methodology and preliminary results of a prospective observational study

Background There is currently no practice-based, multicenter database of poisoned patients admitted to intensive care units (ICUs). The INTOXICATE study, endorsed by the ESICM and EAPCCT, aimed to determine the rate of eventful admissions among acutely intoxicated adult ICU patients. Methods Ethical approval was obtained for this multicenter, prospective observational study, and data-sharing agreements were signed with each participating center. An electronic case report form was used to collect data on patient demographics, exposure, clinical characteristics, investigations, treatment, and in-hospital mortality data. The primary outcome, ‘eventful admission’, was a composite outcome defined as the rate of patients who received any of the following treatments in the first 24 h after the ICU admission: oxygen supplementation with a FiO2 > 40%, mechanical ventilation, vasopressors, renal replacement therapy (RRT), cardiopulmonary resuscitation, antidotes, active cooling, fluid resuscitation (> 1.5 L of intravenous fluid of any kind), sedation, or who died in the hospital. Results Seventy-eight ICUs, mainly from Europe, but also from Australia and the Eastern Mediterranean, participated. A total of 2,273 patients were enrolled between November 2020 and June 2023. The median age of the patients was 41 years, 72% were exposed to intoxicating drugs. The observed rate of patients with an eventful ICU admission was 68% (n = 1546/2273 patients). The hospital mortality was 4.5% (n = 103/2273). Conclusions The vast majority of patients survive, and approximately one third of patients do not receive any ICU-specific interventions after admission in an intensive care unit for acute intoxication. High-quality detailed clinical data have been collected from a large cohort of acutely intoxicated ICU patients, providing information on the pattern of severe acute poisoning requiring intensive care admission and the outcomes of these patients. Trial registration: OSF registration ID: osf.io/7e5uy

Green fabrication of stable lead-free bismuth based perovskite solar cells using a non-toxic solvent

The very fast evolution in certified efficiency of lead-halide organic-inorganic perovskite solar cells to 24.2%, on par and even surpassing the record for polycrystalline silicon solar cells (22.3%), bears the promise of a new era in photovoltaics and revitalisation of thin film solar cell technologies. However, the presence of toxic lead and particularly toxic solvents during the fabrication process makes large-scale manufacturing of perovskite solar cells challenging due to legislation and environment issues. For lead-free alternatives, non-toxic tin, antimony and bismuth based solar cells still rely on up-scalable fabrication processes that employ toxic solvents. Here we employ non-toxic methyl-acetate solution processed (CH3NH3)3Bi2I9 films to fabricate lead-free, bismuth based (CH3NH3)3Bi2I9 perovskites on mesoporous TiO2 architecture using a sustainable route. Optoelectronic characterization, X-ray diffraction and electron microscopy show that the route can provide homogeneous and good quality (CH3NH3)3Bi2I9 films. Fine-tuning the perovskite/hole transport layer interface by the use of conventional 2,2′,7,7′-tetrakis (N,N′-di-p-methoxyphenylamino)−9,9′-spirbiuorene, known as Spiro-OMeTAD, and poly(3-hexylthiophene-2,5-diyl - P3HT as hole transporting materials, yields power conversion efficiencies of 1.12% and 1.62% under 1 sun illumination. Devices prepared using poly(3-hexylthiophene-2,5-diyl hole transport layer shown 300 h of stability under continuous 1 sun illumination, without the use of an ultra violet-filter

Progress on lead-free metal halide perovskites for photovoltaic applications: a review

ABSTRACT: Metal halide perovskites have revolutionized the field of solution-processable photovoltaics. Within just a few years, the power conversion efficiencies of perovskite-based solar cells have been improved significantly to over 20%, which makes them now already comparably efficient to silicon-based photovoltaics. This breakthrough in solution-based photovoltaics, however, has the drawback that these high efficiencies can only be obtained with lead-based perovskites and this will arguably be a substantial hurdle for various applications of perovskite-based photovoltaics and their acceptance in society, even though the amounts of lead in the solar cells are low. This fact opened up a new research field on lead-free metal halide perovskites, which is currently remarkably vivid. We took this as incentive to review this emerging research field and discuss possible alternative elements to replace lead in metal halide perovskites and the properties of the corresponding perovskite materials based on recent theoretical and experimental studies. Up to now, tin-based perovskites turned out to be most promising in terms of power conversion efficiency; however, also the toxicity of these tin-based perovskites is argued. In the focus of the research community are other elements as well including germanium, copper, antimony, or bismuth, and the corresponding perovskite compounds are already showing promising properties. GRAPHICAL ABSTRACT: [Image: see text

The relationship between expectation, experience and perception of labour pain: an observational study.

The present study was aimed to assess the relationship between pain expectation before labour, labour pain and pain perception after the labour. Pregnant women were asked to rate their pain level on a standard continuous visual analogue scale at various time points. Pain expectancy (PE), labour pain (LP) and postpartum pain perception (PPP) scores were calculated. The final study group was composed of 230 pregnant women after exclusions. Mean age of pregnant women was 26.2 ± 5.79. The mean PE, LP, and PPP scores were 70.11 ± 18.82, 75.72 ± 19.2 and 65.84 ± 19.56, respectively. The difference among pain scores was statistically significant (p < 0.001). There was a positive correlation between PE and LP or PE and PPP scores (p = 0.27 and p = 0.21). The correlations were statistically significant (p = 0.01 or p = 0.01). In addition, there was a positive correlation between LP and PPP scores (p = 0.87) and the correlation was statistically significant (p = 0.01). This study showed that, if pregnant women had lower expectations of pain before the labour, they indeed experienced lower amount of pain during the labour