Charge transport and gas sensing properties of all inorganic lead halide perovskite nanocrystals

Over the past decades, all-inorganic perovskite nanomaterials have garnered widespread interest for next-generation photovoltaics and optoelectronic applications. Among nanostructured perovskites, zero-dimensional (0D) perovskites, known as quantum dots (QDs) or nanocrystals (NCs), exhibit excellent quantum efficiency, size-tunable optical properties, and narrow emission band width. In addition, solution-processed fabrication allows facile and cost-effective deposition of smooth and high-quality thin films. However, low conductivity of perovskite quantum dots-based devices remains as a bottleneck due to long-chain organic ligands forming an insulating medium around perovskite quantum dots. Much progress has recently been made in ligand engineering and passivation of perovskite quantum dots to improve charge carrier transport and reduce trap density. In this work, two sequential treatments are employed to enhance charge transport, i.e., soft soaking with Methyl acetate (MeOAc) and annealing-induced Ostwald ripening at 120°C, which effectively removes ligands and modifies trap density of the thin film devices. Charge transport behaviour of perovskite quantum dots has been investigated via field effect transistor and gas sensor, which has outperformed previous work with superior mobility (~0.023 cm2 V-1 s-1) and 9.7 time higher carrier lifetime compared to as-prepared perovskite quantum dots. Besides, quantum dot films are used as a gas sensor, which shows good output after the treatments with a high selectivity towards NO2. These results achieved on CsPbBr3 nanocrystal thin films provide new insights on developing perovskite nanomaterials for next-generation optoelectronic applications

Development of Financial Support Program for High Risk Pregnant Women

AbstractObjectivesThe purpose of this study was to develop a financial support program for high-risk pregnant women based on opinions obtained using a questionnaire survey.MethodsThe program development involved two steps: (1) developing a questionnaire through reviewing previous financial support programs for maternal care and then validating it via professional consultation; and (2) drafting a financial support program. Sixty professionals, 26 high-risk pregnant women, and 100 program implementers completed the questionnaire between August 2014 and October 2014.ResultsBased on the obtained professional consultation and survey investigation, the framework of the financial support program was constructed. The suggested recipients were mothers with early labor pains, mothers who have been hospitalized for > 3 weeks, and mothers who used uterine stimulant Pitocin during hospitalization. All hospitalization, medication, and examination costs needed to be supported considering the income level of the recipient.ConclusionA basic policy for financially supporting high-risk pregnant women has been developed. The efficacy and feasibility of the policy needs to be carefully examined in future studies

Challenges of Country Modeling with Databases, Newsfeeds, and Expert Surveys

According to expert practitioners and researchers in the field of human behavior modeling ([Silverman et al., 2002; Pew and Mavor, 1998; Ritter et al., 2003]), a common central challenge now confronting designers of HBM (human-behavior-modeling) applications is to increase the realism of the synthetic agents\u27 behavior and coping abilities. It is well accepted in the HBM (human-behavior-modeling) community that cognitively detailed, thick models are required to provide realism. These models require that synthetic agents be endowed with cognition and personality, physiology, and emotive components. (We will hereafter refer to these rich models as cognitively detailed models or thick agents. ) To make these models work, one must find ways to integrate scientific know-how from many disciplines, and to integrate concepts and insights from hitherto fragmented and partial models from the social sciences, particularly from psychology, cultural studies, and political science. One consequence of this kind of integration of multiple and heterogeneous concepts and models is that we frequently end up with a large feature space of parameters that then need to be filled in with data

Microspinning: Local Surface Mixing via Rotation of Magnetic Microparticles for Efficient Small-Volume Bioassays

The need for high-throughput screening has led to the miniaturization of the reaction volume of the chamber in bioassays. As the reactor gets smaller, surface tension dominates the gravitational or inertial force, and mixing efficiency decreases in small-scale reactions. Because passive mixing by simple diffusion in tens of microliter-scale volumes takes a long time, active mixing is needed. Here, we report an efficient micromixing method using magnetically rotating microparticles with patterned magnetization induced by magnetic nanoparticle chains. Because the microparticles have magnetization patterning due to fabrication with magnetic nanoparticle chains, the microparticles can rotate along the external rotating magnetic field, causing micromixing. We validated the reaction efficiency by comparing this micromixing method with other mixing methods such as simple diffusion and the use of a rocking shaker at various working volumes. This method has the potential to be widely utilized in suspension assay technology as an efficient mixing strategy

Distinct Developmental Features of Olfactory Bulb Interneurons

The olfactory bulb (OB) has an extremely higher proportionof interneurons innervating excitatory neurons than otherbrain regions, which is evolutionally conserved across species.Despite the abundance of OB interneurons, little is knownabout the diversification and physiological functions ofOB interneurons compared to cortical interneurons. In thisreview, an overview of the general developmental processof interneurons from the angles of the spatial and temporalspecifications was presented. Then, the distinct featuresshown exclusively in OB interneurons development andmolecular machinery recently identified were discussed.Finally, we proposed an evolutionary meaning for thediversity of OB interneurons.1

One-Step Generation of a Drug-Releasing Hydrogel Microarray-On-A-Chip for Large-Scale Sequential Drug Combination Screening

Large-scale screening of sequential drug combinations, wherein the dynamic rewiring of intracellular pathways leads to promising therapeutic effects and improvements in quality of life, is essential for personalized medicine to ensure realistic cost and time requirements and less sample consumption. However, the large-scale screening requires expensive and complicated liquid handling systems for automation and therefore lowers the accessibility to clinicians or biologists, limiting the full potential of sequential drug combinations in clinical applications and academic investigations. Here, a miniaturized platform for high-throughput combinatorial drug screening that is "pipetting-free" and scalable for the screening of sequential drug combinations is presented. The platform uses parallel and bottom-up formation of a heterogeneous drug-releasing hydrogel microarray by self-assembly of drug-laden hydrogel microparticles. This approach eliminates the need for liquid handling systems and time-consuming operation in high-throughput large-scale screening. In addition, the serial replacement of the drug-releasing microarray-on-a-chip facilitates different drug exchange in each and every microwell in a simple and highly parallel manner, supporting scalable implementation of multistep combinatorial screening. The proposed strategy can be applied to various forms of combinatorial drug screening with limited amounts of samples and resources, which will broaden the use of the large-scale screening for precision medicine

Effects of residential greenness on clinical outcomes of patients with chronic kidney disease: a large-scale observation study

Background: As industrialization and urbanization are accelerating, the distribution of green areas is decreasing, particularly in developing countries. Since the 2000s, the effects of surrounding greenness on self-perceived health, including physical and mental health, longevity, and obesity have been reported. However, the effects of surrounding green space on chronic kidney disease are not well understood. Therefore, we investigated the impact of residential greenness on the mortality of chronic kidney disease patients and progression from chronic kidney disease to end-stage renal disease (ESRD). Methods: Using a large-scale observational study, we recruited chronic kidney disease patients (n = 64,565; mean age, 54.0 years; 49.0% of male) who visited three Korean medical centers between January 2001 and December 2016. We investigated the hazard ratios of clinical outcomes per 0.1-point increment of exposure to greenness using various models. Results: During the mean follow-up of 6.8 +/- 4.6 years, 5,512 chronic kidney disease patients developed ESRD (8.5%) and 8,543 died (13.2%). In addition, a 0.1-point increase in greenness reduced all-cause mortality risk in chronic kidney disease and ESRD patients and progression of chronic kidney disease to ESRD in a fully adjusted model. The association between mortality in ESRD patients and the normalized difference vegetation index was negatively correlated in people aged >65 years, who had normal weight, were nonsmokers, and lived in a nonmetropolitan area. Conclusion: Chronic kidney disease patients who live in areas with higher levels of greenness are at reduced risk of all-cause mortality and progression to ESRD.Y

Enantioselective Alkynylation of Trifluoromethyl Ketones Catalyzed by Cation-Binding Salen Nickel Complexes

Cation‐binding salen nickel catalysts were developed for the enantioselective alkynylation of trifluoromethyl ketones in high yield (up to 99 %) and high enantioselectivity (up to 97 % ee). The reaction proceeds with substoichiometric quantities of base (10–20 mol % KOt‐Bu) and open to air. In the case of trifluoromethyl vinyl ketones, excellent chemo‐selectivity was observed, generating 1,2‐addition products exclusively over 1,4‐addition products. UV‐vis analysis revealed the pendant oligo‐ether group of the catalyst strongly binds to the potassium cation (K⁺) with 1:1 binding stoichiometry (K_a=6.6×10⁵ M⁻¹)

Community Resources and Educational Opportunities in Detroit: Baseline Assessment of Academic Progress Using the 2005-2009 Cohort of High School Students

This baseline report was prepared for the Detroit Schools-Higher Education Consortium. The report provided research support for educational improvement efforts by this consortium of universities and community-­based organizations working in collaboration with Detroit schools.This research report contributes a community resource theory of change applied to a Detroit Public Schools (DPS) case study of high school students. The research study examines changes in Detroit Education from 2000 to 2010, including policy and demographic changes. We also examined the impact of community resources on educational opportunities using a 2005-2009 student cohort database, Census data, and information on community resources. We examined three student outcomes: on-time graduation rate, grade point average (GPA), and school transfer during high school. The study proposes and tests a community resources theory of educational opportunity supporting Detroit students. The results support a community resource theory of change that includes more community-school partnerships in neighborhoods.Ford Foundationhttps://deepblue.lib.umich.edu/bitstream/2027.42/150103/1/Detroit Baseline Assessment Report (2019).pdfDescription of Detroit Baseline Assessment Report (2019).pdf : Main Working Repor

Clinical outcomes associated with long-term exposure to airborne particulate pollution in kidney transplant recipients

Background Researchers have yet to investigate the specific association between 10-μm particulate matter (PM10) levels and the risk of graft failure, kidney disease, or the functional decline of transplanted kidneys, in kidney transplant recipients (KTRs). Furthermore, we know very little about the association between PM10 levels and the development of allograft rejection in transplanted kidneys. Identification of air pollution as a potential contributor to kidney disease could help reduce future disease burden, stimulate policy discussions on the importance of reducing air pollution with respect to health and disease, and increase public awareness of the hazards of air pollution. We aimed to evaluate the relationship of PM10 with the risk of graft failure, mortality, and decline of graft function in KTRs. Methods Air pollutant data were obtained from the Korean National Institute of Environmental Research. We then investigated potential associations between these data and the clinical outcomes of 1532 KTRs who underwent kidney transplantation in a tertiary hospital between 2001 and 2015. Survival models were used to evaluate the association between PM10 concentrations and the risk of death-censored graft failure (DCGF), all-cause mortality, and biopsy-proven rejection (BPR), over a median follow-up period of 6.31 years. Results The annual mean PM10 exposure after kidney transplantation was 27.1 ± 8.0 μg/m3. Based on 1-year baseline exposure, 1 μg/m3 increase in PM10 concentration was associated with an increased risk of DCGF (hazard ratio (HR): 1.049; 95% confidence interval (CI): 1.014–1.084) and BPR (HR: 1.053; 95% CI: 1.042–1.063). Fully adjusted models showed that all-cause mortality was significantly associated with 1-year average PM10 concentrations (HR, 1.09; 95% CI, 1.043 to 1.140). Conclusions Long-term PM10 exposure is significantly associated with BPR, DCGF, and all-cause mortality in KTRs.This work was supported by the Seoul National University Research Grant in 2018, the Korean Society of Nephrology Grant in 2018 (BAXTER), and by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2019R1A6A3A01095329) and the Global Research Lab through the NRF, funded by the Ministry of Science and ICT (Information and Communication Technologies) in South Korea (grant number K2100400000110A0500–00710; H Kim)