Risk factors for visceral leishmaniasis in a new epidemic site in Amhara Region, Ethiopia

We conducted a case-control study to evaluate risk factors for visceral leishmaniasis during an epidemic in a previously unaffected district of Ethiopia. We also collected blood and bone marrow specimens from dogs in the outbreak villages. In multivariable analyses of 171 matched case-control pairs, dog ownership, sleeping under an acacia tree during the day, and habitually sleeping outside at night were associated with significantly increased risk. Specimens from 7 (3.8%) dogs were positive by immunofluorescent antibody test (IFAT) and both enzyme-linked immunosorbent assays (ELISAs), whereas Leishmania DNA was detected in 5 (2.8%) bone marrow aspirates (from 3 seropositive and 2 seronegative dogs). Insecticide-treated nets may only protect a portion of those at risk. Further research on the vectors, the role of the dog in the transmission cycle, and the effect of candidate interventions are needed to design the best strategy for control

Origin of Sn(II) oxidation in tin halide perovskites

Tin-halide perovskites have great potential as photovoltaic materials, but their performance is hampered by undesirable oxidation of Sn(ii) to Sn(iv). NMR proves DMSO to be a main cause of oxidation

Fluoride Chemistry in Tin Halide Perovskites

Tin is the frontrunner for substituting toxic lead in perovskite solar cells. However, tin suffers the detrimental oxidation of SnII to SnIV. Most of reported strategies employ SnF2 in the perovskite precursor solution to prevent SnIV formation. Nevertheless, the working mechanism of this additive remains debated. To further elucidate it, we investigate the fluoride chemistry in tin halide perovskites by complementary analytical tools. NMR analysis of the precursor solution discloses a strong preferential affinity of fluoride anions for SnIV over SnII, selectively complexing it as SnF4. Hard X-ray photoelectron spectroscopy on films shows the lower tendency of SnF4 than SnI4 to get included in the perovskite structure, hence preventing the inclusion of SnIV in the film. Finally, small-angle X-ray scattering reveals the strong influence of fluoride on the colloidal chemistry of precursor dispersions, directly affecting perovskite crystallization

Photovoltaic potential of tin perovskites revealed through layer-by-layer investigation of optoelectronic and charge transport properties

Tin perovskites are the most promising environmentally friendly alternative to lead perovskites. Among tin perovskites, FASnI3 (CH4N2SnI3) shows optimum band gap, and easy processability. However, the performance of FASnI3 based solar cells is incomparable to lead perovskites for several reasons, including energy band mismatch between the perovskite absorber film and the charge transporting layers (CTLs) for both types of carriers, i.e., for electrons (ETLs) and holes (HTLs). However, the band diagrams in the literature are inconsistent, and the charge extraction dynamics are poorly understood. In this paper, we study the energy band positions of FASnI3 based perovskites using Kelvin probe (KP) and photoelectron yield spectroscopy (PYS) to provide a precise band diagram of the most used device stack. In addition, we analyze the defects within the current energetic landscape of tin perovskites. We uncover the role of bathocuproine (BCP) in enhancing the electron extraction at the fullerene C60/BCP interface. Furthermore, we used transient surface photovoltage (tr-SPV) for the first time for tin perovskites to understand the charge extraction dynamics of the most reported HTLs such as NiOx and PEDOT, and ETLs such as C60, ICBA, and PCBM. Finally, we used Hall effect, KP, and time-resolved photoluminescence (TRPL) to estimate an accurate value of the p-doping concentration in FASnI3 and showed a consistent result of 1.5 * 1017 cm-3. Our findings prove that the energetic system of tin halide perovskites is deformed and should be redesigned independently from lead perovskites to unlock the full potential of tin perovskites.Comment: 22 pages, 5 figure

Characteristics of patients with venous thromboembolism and atrial fibrillation in Venezuela

<p>Abstract</p> <p>Background</p> <p>Studies describing venous thromboembolic event (VTEE) and atrial fibrillation (AF) in South American populations are limited. The aim of this cross-sectional study was to describe the characteristics of Venezuelan patients admitted and treated for these conditions.</p> <p>Methods</p> <p>A retrospective medical record review of 1397 consecutive patients admitted to three private hospitals or clinics between January 2000 and December 2005 was performed. Data was collected on demographics, anthropometrics, hospital visit, comorbidities and treatment.</p> <p>Results</p> <p>Among 401 VTEE and 996 AF patients, men were more likely to have AF (58%) while more women experienced a VTEE (58%). Most patients were admitted via the emergency room (87%) and had only one event during the study period (83%). Common comorbidities included hypertension (46%), heart failure (17%), diabetes (12%) and congestive heart failure (11%). Characteristics of Venezuelan patients with VTEE and AF are similar to that reported in the literature for other populations.</p> <p>Conclusions</p> <p>These results provide background characteristics for future studies assessing risk factors for AF and VTEE in South American populations.</p

Age–sex differences in the global burden of lower respiratory infections and risk factors, 1990–2019 : results from the Global Burden of Disease Study 2019

Background: The global burden of lower respiratory infections (LRIs) and corresponding risk factors in children older than 5 years and adults has not been studied as comprehensively as it has been in children younger than 5 years. We assessed the burden and trends of LRIs and risk factors across all age groups by sex, for 204 countries and territories. Methods: In this analysis of data for the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019, we used clinician-diagnosed pneumonia or bronchiolitis as our case definition for LRIs. We included International Classification of Diseases 9th edition codes 079.6, 466–469, 470.0, 480–482.8, 483.0–483.9, 484.1–484.2, 484.6–484.7, and 487–489 and International Classification of Diseases 10th edition codes A48.1, A70, B97.4–B97.6, J09–J15.8, J16–J16.9, J20–J21.9, J91.0, P23.0–P23.4, and U04–U04.9. We used the Cause of Death Ensemble modelling strategy to analyse 23 109 site-years of vital registration data, 825 site-years of sample vital registration data, 1766 site-years of verbal autopsy data, and 681 site-years of mortality surveillance data. We used DisMod-MR 2.1, a Bayesian meta-regression tool, to analyse age–sex-specific incidence and prevalence data identified via systematic reviews of the literature, population-based survey data, and claims and inpatient data. Additionally, we estimated age–sex-specific LRI mortality that is attributable to the independent effects of 14 risk factors. Findings: Globally, in 2019, we estimated that there were 257 million (95% uncertainty interval [UI] 240–275) LRI incident episodes in males and 232 million (217–248) in females. In the same year, LRIs accounted for 1·30 million (95% UI 1·18–1·42) male deaths and 1·20 million (1·07–1·33) female deaths. Age-standardised incidence and mortality rates were 1·17 times (95% UI 1·16–1·18) and 1·31 times (95% UI 1·23–1·41) greater in males than in females in 2019. Between 1990 and 2019, LRI incidence and mortality rates declined at different rates across age groups and an increase in LRI episodes and deaths was estimated among all adult age groups, with males aged 70 years and older having the highest increase in LRI episodes (126·0% [95% UI 121·4–131·1]) and deaths (100·0% [83·4–115·9]). During the same period, LRI episodes and deaths in children younger than 15 years were estimated to have decreased, and the greatest decline was observed for LRI deaths in males younger than 5 years (–70·7% [–77·2 to –61·8]). The leading risk factors for LRI mortality varied across age groups and sex. More than half of global LRI deaths in children younger than 5 years were attributable to child wasting (population attributable fraction [PAF] 53·0% [95% UI 37·7–61·8] in males and 56·4% [40·7–65·1] in females), and more than a quarter of LRI deaths among those aged 5–14 years were attributable to household air pollution (PAF 26·0% [95% UI 16·6–35·5] for males and PAF 25·8% [16·3–35·4] for females). PAFs of male LRI deaths attributed to smoking were 20·4% (95% UI 15·4–25·2) in those aged 15–49 years, 30·5% (24·1–36·9) in those aged 50–69 years, and 21·9% (16·8–27·3) in those aged 70 years and older. PAFs of female LRI deaths attributed to household air pollution were 21·1% (95% UI 14·5–27·9) in those aged 15–49 years and 18·2% (12·5–24·5) in those aged 50–69 years. For females aged 70 years and older, the leading risk factor, ambient particulate matter, was responsible for 11·7% (95% UI 8·2–15·8) of LRI deaths. Interpretation: The patterns and progress in reducing the burden of LRIs and key risk factors for mortality varied across age groups and sexes. The progress seen in children younger than 5 years was clearly a result of targeted interventions, such as vaccination and reduction of exposure to risk factors. Similar interventions for other age groups could contribute to the achievement of multiple Sustainable Development Goals targets, including promoting well eing at all ages and reducing health inequalities. Interventions, including addressing risk factors such as child wasting, smoking, ambient particulate matter pollution, and household air pollution, would prevent deaths and reduce health disparities. Funding: Bill & Melinda Gates Foundation. © 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license **Please note that there are multiple authors for this article therefore only the name of the first 30 including Federation University Australia affiliate “Muhammad Aziz Rahman and Huy Nguyen” is provided in this record*

Ionic liquid Stabilizing high‐efficiency tin halide perovskite solar cells

Tin halide perovskites attract incremental attention to deliver lead‐free perovskite solar cells. Nevertheless, disordered crystal growth and low defect formation energy, related to Sn(II) oxidation to Sn(IV), limit the efficiency and stability of solar cells. Engineering the processing from perovskite precursor solution preparation to film crystallization is crucial to tackle these issues and enable the full photovoltaic potential of tin halide perovskites. Herein, the ionic liquid n‐butylammonium acetate (BAAc) is used to tune the tin coordination with specific O…Sn chelating bonds and NH…X hydrogen bonds. The coordination between BAAc and tin enables modulation of the crystallization of the perovskite in a thin film. The resulting BAAc‐containing perovskite films are more compact and have a preferential crystal orientation. Moreover, a lower amount of Sn(IV) and related chemical defects are found for the BAAc‐containing perovskites. Tin halide perovskite solar cells processed with BAAc show a power conversion efficiency of over 10%. This value is retained after storing the devices for over 1000 h in nitrogen. This work paves the way toward a more controlled tin‐based perovskite crystallization for stable and efficient lead‐free perovskite photovoltaics.Natural Science Foundation of ChinaShanghai Synchrotron Radiation FacilityEuropean Research CouncilEuropean Union's Horizon 202

Fluoridchemie in Zinn‐Halogenid‐Perowskiten

Zinn ist der Top-Favorit für den Ersatz von giftigem Blei in Perowskit-Solarzellen. Allerdings kommt es dabei verstärkt zu der unerwünschten Oxidation von SnII zu SnIV. Die herkömmlichen Verfahren verwenden SnF2 in der Perowskit-Vorläuferlösung, um die Bildung von SnIV zu verhindern. Dennoch bleibt der Wirkmechanismus des Additivs unklar. Um diesen eingehender zu erläutern, untersuchen wir die Fluoridchemie in Zinn-Halogenid-Perowskiten mit einander ergänzenden Analyseverfahren. NMR-Spektroskopie der Vorläuferlösung offenbart eine stark bevorzugte Affinität der Fluoridanionen für SnIV gegenüber SnII, wodurch dieses selektiv als SnF4 komplexiert wird. Harte Röntgenphotoelektronenspektroskopie an Dünnschichten zeigt die geringere Bereitschaft von SnF4 gegenüber SnI4, in die Perowskit-Struktur eingebaut zu werden und verhindert somit den Einschluss von SnIV in der Dünnschicht. Abschließend offenbart Röntgen-Kleinwinkelstreuung den starken Einfluss vom Fluorid auf die kolloidale Chemie der Vorläuferlösungen, der sich direkt auf die darauffolgende Kristallisation auswirkt.European Research Council (ERC)Peer Reviewe