Santos Field (shipdamage4)
We introduce a new family of 2D materials with unique structure and optoelectronic properties, namely, single-layer gold(I) halides (AuHals). We propose their stability as well as structural, electronic, and optical properties using first-principles calculations. The cleavage energy is found to be similar to that of graphene from graphite, indicating the possibility for mechanical exfoliation. We show that AuHals are stable and have tunable direct (AuBr) and indirect (AuI) band gaps depending on the number of layers. We discuss the possible origin of the giant spin-orbit coupling (SOC) induced conduction band splitting in terms of orbital-decomposed band structure to guide future investigations on the design of materials with highly effective SOC. Exceptionally high excitonic binding energy, high hole mobility, and tunable band gaps indicate that AuHals are promising candidates for optoelectronic devices with excellent performance.Excess concentrations of lead (Pb) were found in tap water from drinking water supply systems of high-rise buildings in 11 public rental housing (PRH) estates in Hong Kong, posing threats to public health. The copper supply lines are fitted with lead-soldered connections and brass fixtures and faucets. The causes of excess lead are studied through field sampling on occupied households, experiments on prototype supply chains, and 3D numerical modeling. The tap water lead concentration of 129 households in the PRH estates was sampled using a specially designed protocol, revealing the highly variable lead concentration variations induced by sources along the supply chain. Lead concentration variation at consumer tap and its relation with various lead sources are studied in a full-scale test rig. #link# A 3D computational fluid dynamics (CFD) model is successfully developed to interpret the time variation of lead concentrations at the consumer tap. Model predictions of the complex variation of dissolved lead are in good agreement with data and confirm lead solder in copper pipe connections as a major cause of the "lead water" episode in Hong Kong. The CFD calculations demonstrate the importance of turbulent diffusion and shear flow dispersion in the modeling of lead; the use of a "plug flow" approximation can result in significant overestimation of lead concentration. The findings provide a basis for lead risk assessment of different water sampling strategies in densely populated high-rise buildings in Megacities. The incidence of type 1 diabetes mellitus (T1DM) among children is high in Europe and the USA and relatively low in Asia, including Korea. The present study aimed to investigate the incidence and prevalence of childhood-onset T1DM in Korea and examine trends in incidence. This study was conducted using the national registry data provided by the Health Insurance Review and Assessment Service in Korea from 2007 to 2017. BRM/BRG1 ATP Inhibitor-1 solubility dmso included children aged 0 to 14 years who were newly registered with a T1DM diagnosis each year (code E10). A total of 29,013 children were registered. The overall incidence of T1DM was 4.45 per 100,000 persons (girls, 4.93; boys, 4.01). The overall incidence of childhood-onset T1DM in Korea increased from 3.70 in 2008 to 4.77 in 2016 (P=0.002). The incidence of T1DM increased from 3.07 in 2008 to 4.89 in 2016 (P<0.001) among boys. Although the incidence of the disease increased significantly among boys aged 5-9 and 10-14 years, it remained constant among girls (4.39 in 2008, 4.64 in 2016). The overall prevalence of childhood-onset T1DM in Korea increased from 32.85 in 2007 to 41.03 per 100,000 persons in 2017 (girls, 35.54 to 43.88; boys, 32.85 to 41.03). We calculated relatively accurate incidence and prevalence of childhood-onset T1DM from a nation-based registry. The incidence increased by 3% to 4% every year from 2007 to 2017. The increasing trend is noteworthy compared with previous repo