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Composition Engineering in Two-Dimensional Pb-Sn-Alloyed Perovskites for Efficient and Stable Solar Cells

Environmentally friendly tin (Sn)-based metallic halide perovskites suffer from oxidation and morphological issues. Here, we demonstrate the composition engineering of Pb-Sn-alloyed two-dimensional (2D) Ruddlesden-Popper perovskites, (BA)2(MA)3Pb4-xSnxI13, for efficient and stable solar cell applications. Smooth thin films with high surface coverage are readily formed without using any additive ow

Atmospheric mercury pollution in the xi’an area, china, studied by differential absorption lidar

Measurements of the atmospheric concentration of polluting atomic mercury were performed using the differential absorption lidar (DIAL) technique in the Lintong district, about 35 km northeast of Xi’an, the capital of the Shaanxi province, China. Concentrations ranging from 2 to 13 ng/m3 were observed. As uniquely enabled by the lidar technique, representative average concentrations, integrated ov

Intrauterine vertical SARS-CoV-2 infection : a case confirming transplacental transmission followed by divergence of the viral genome

A 27-year-old woman (gravida 2, para 1) was transported to the regional university hospital in gestational week (GW) 34 + 4 due to a three-day history of fever, abdominal pain and reduced foetal movements. She had developed a dry cough one day prior to the admission (Figure S1). The woman, was slightly overweight (BMI 27 kg/m2 ) but otherwise healthy. She had normal antenatal check-ups and an obst

When the impossible becomes possible : COVID-19’s impact on work and travel patterns in Swedish public agencies

Background: The COVID-19 pandemic has rapidly led to some of the most revolutionary changes in private and professional life around the world. While the extent and duration of these changes are not certain, they have already had a great impact on travel patterns. This is also the case in Sweden, despite its relatively liberal approach to restrictions, which relies on voluntary measures such as soc

Herbivores reduce seedling recruitment in alpine plant communities

Through changes in climate and other environmental factors, alpine tundra ecosystems are subject to increased cover of erect shrubs, reduced predictability of rodent dynamics and changes in wild and domesticated herbivore densities. To predict the dynamics of these ecosystems, we need to understand how these simultaneous changes affect alpine vegetation. In the long term, vegetation dynamics may d

Preliminary results from clinical validation study of a method for non-invasive assessment of atrioventricular node refractoriness during atrial fibrillation

The purpose of this study is to evaluate our previously proposed model-based, non-invasive approach to assess atrioventricular (AV) node refractory periods during atrial fibrillation (AF) by comparing its estimates to the invasively assessed AV node refractory periods. Patients referred to the hospital for pulmonary vein isolation (PVI), being in AF upon arrival, are included in the study. Using o

Applying the ecosystem model in a new context? The case of business incubation in Oman

This paper studies entrepreneurship ecosystem development in a context little discussed in the extant literature to date: Oman. Specifically, it focuses on business incubation (BI) initiatives as a policy tool for developing the local, regional, and national systems of supporting entrepreneurship and SME growth. Although BI’s are a popular policy measure for ecosystem development, spreading global

A Study on Learning Activities in Supplemental Instruction

The present study focuses on the learning activities that are used in practice in supplemental instruction (SI) in basic engineering courses and the extent to which they are meaning oriented. A survey method, based on action verbs, is used and complemented with a student experience questionnaire on SI. The verbs chosen by both the students attending SI and the SI leaders to identify learning activ

RIFM fragrance ingredient safety assessment, methyl-2,2-dimethyl-6-methylene-1-cyclohexanecarboxylate, CAS Registry Number 81752-87-6

The existing information supports the use of this material as described in this safety assessment. Methyl-2,2-dimethyl-6-methylene-1-cyclohexanecarboxylate was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data show that methyl-2,2-dimethyl-6-methylene-1-cyclohex