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Except the tunable photoluminescent property, graphene quantum dots (GQDs) with special structures have also exhibited other novel properties. Herein, GQDs played a novel coreactant role in Ru(bpy) 3 2+ /GQDs system to increase the anodic ECL signal of Ru(bpy) 3 2+ , which has been testified by ultraviolet, fluorescence, and electrochemiluminescence (ECL) experiments. Based on the coreactant mechanism of Ru(bpy) 3 2+ /GQDs system, a chlorinated phenol-related quenching ECL sensor was designed and the sensor showed a good linear relationship in the range from 0.60 to 55 μM with the detection limit of 1.4 × 10 −8 M (S/N = 3). These results were not only beneficial to resolve the structure of GQDs, but also expanded the application field of GQDs. [ABSTRACT FROM AUTHOR]

To quantify the physical/chemical properties, and the formation and growth processes of aerosol particles on mountainous regions in Southeast China, an intensive field campaign was conducted from April to July 2008 on the top of Mt. Huang (1840 m above mean sea level). The average particle number concentration was 2.35 × 10 3 cm − 3 , and the ultrafine particles (< 0.1 μm) represented 70.5% of the total particle number concentration. Excluding the accumulation mode particles, the average daytime particle number concentrations were prominently higher than those measured at nighttime, suggesting there was a diurnal pattern of changes between planetary boundary layer and free troposphere air. The aerosol spectra were classified into two categories: the first category (FCS) exhibited a clear diurnal cycle, with relatively higher number concentration (3.19 × 10 3 cm − 3 ), smaller sizes and air masses from the inland; the second category (SCS) presented less obvious diurnal cycle, with lower number concentration (1.88 × 10 3 cm − 3 ), larger sizes and air masses from coastal regions. Air mass sources, weather conditions, and new particle formation (NPF) events were responsible for the differences of these two particle spectra. Six NPF events were identified, which usually began at 10:00–11:00 LT, with the estimated formation rate J 10 in the range of 0.09–0.30 cm − 3 s − 1 and the growth rate at 1.42–4.53 nm h − 1 . Wind speed, sulfur dioxide and ozone concentrations were higher on NPF days than those on non-NPF days, whereas temperature, relative humidity, concentrations of nitrogen oxide and carbonic oxide were lower on NPF days. Sulfur dioxide and ozone might be main potentially precursor gases for those NPF events. The NPF events at Mt. Huang corresponded closely to a southwest winds. These results are useful for improving our understanding of the main factors controlling the variation of aerosol size distribution and NPF events in this region. [ABSTRACT FROM AUTHOR]

Abstract: A new photoelectrochemical (PEC) biosensor was developed using low-toxic Ag2S QDs as photoelectrochemically active species. Energy levels of Ag2S and Ag2Se QD were compared to explain their differences in the PEC performance. The preparation condition of Ag2S QD was optimized and its structure characterization was measured. Then the developed photoelectric active interface was used to detect glucose and MCF-7 cancer cell and showed the good sensitivity and specificity. Under optimal condition, detection limits of 3.2×10−5 M for glucose and 98cells/mL for MCF-7 cell were achieved. Thus, the prepared Ag2S QD could serve as an excellent and promising photoelectric active material in the PEC biosensor. [Copyright &y& Elsevier]

Abstract: Nanosized TiO2 photocatalysts of anatase, rutile and mixed-phase were synthesized through hydrolysis method. The influence of the interface junction between anatase and rutile TiO2 on the photo-generated charge carriers properties were studied by Kelvin probe (KP), surface photovoltage (SPV) and transient photovoltage (TPV) techniques. The KP results revealed that the difference of the surface work function between anatase and rutile might cause the formation of built-in field at the interface in mixed-phase TiO2. The role of the interface junction was further testified through the characteristics of photo-generated charge carriers by SPV and TPV. [Copyright &y& Elsevier]

Abstract: Different sizes of ZnWO4 photocatalysts were synthesized by a hydrothermal method. The as-prepared sample shows highly efficient photocatalytic activity for the degradation of RhB under UV irradiation, which significantly vary with the increase of the hydrothermal temperatures. Surface photovoltage spectrum (SPS), field-induced surface photovoltage spectrum (FI-SPS) and surface photovoltage transient (TPV) techniques are used to investigate the detailed photoinduced charge transfer behavior. Results indicate that the ZnWO4 synthesized at 413K possess the largest BET surface area and the abundant donor surface states which are assumed to inhibit the recombination of the photogenerated electron–hole pairs, and thus a significant enhancement in the reaction rate is observed. [Copyright &y& Elsevier]

Abstract: A novel “signal-on” assay for sensitive and selective detection of Hg2+ in aqueous solution based on mismatched DNA and a molecular light switch complex, [Ru(phen)2(dppz)]2+, was reported in the present work. This Hg2+ specific sensor system composed of two label-free DNA probes with eight T–T mismatches, which could form stable DNA duplexes by thymine–Hg2+–thymine (T–Hg2+–T) in the presence of Hg2+. The luminescence of [Ru(phen)2(dppz)]2+ is very weak in aqueous solution, and significant luminescence can be observed when intercalating into DNA duplexes. By monitoring Hg2+-dependent luminescence intensity enhancement, highly sensitive and selective determination of Hg2+ has been achieved. Under the optimum conditions, the luminescence intensity was proportional to the concentration of Hg2+ in the range of 1.0×10−9–1.5×10−7 M. A detection limit of 3.5×10−10 M Hg2+ was achieved using 3σ. The presence of other metal ions did not interfere with the detection of Hg2+ even at high concentrations. This approach is simple and rapid, which can be used to monitor the Hg2+ concentration in drinking water and natural media within 30min. [Copyright &y& Elsevier]

The Ugi four-component reaction (U-4CR) was utilized to prepare divalent and trivalent cluster mannosides with different scaffolds. The glycoclusters obtained were tested for their relative inhibitory potency against the binding of yeast mannan to concanavalin A by solid-phase enzyme-linked lectin assays (ELLA) using methyl α-d-mannopyranoside as a standard. Among them, a divalent mannoside containing aromatic groups showed the strongest binding affinity to concanavalin A. [Copyright &y& Elsevier]

• Three pathways contributed to ROS accumulation in yeast while being exposed to TCBPA. • TCBPA activated NADPH oxidase through regulation of three pathways. • TCBPA promoted expressions of genes which are responsible for ROS accumulation. • These results clarified that how TCBPA induced ROS accumulation in S. cerevisiae. Tetrachlorobisphenol A (TCBPA) can promote intracellular reactive oxygen species (ROS) accumulation. However, limited attention has been given to mechanisms underlying TCBPA exposure-associated ROS accumulation. Here, such mechanisms were explored in the simple eukaryotic model organism Saccharomyces cerevisiae exposed to multiple concentrations of TCBPA. Addition of diphenyleneiodonium, a specific inhibitor of NADPH oxidase, blocked TCBPA treatment-associated intracellular ROS accumulation. NADPH oxidase can be activated by calcineurin, mitogen-activated protein kinase (MAPK), and tyrosine kinase. Therefore, corresponding specific inhibition respectively on these three kinases was performed and results suggested that the Ca2+ signaling pathway, MAPK pathway, and tyrosine kinase pathway all contributed to the TCBPA exposure-associated intracellular ROS accumulation. In addition, TCBPA exposure-associated up-regulation of genes involved in ROS production and down-regulation of catalase promoted ROS accumulation in S. cerevisiae. To sum up, our current results provide insights into the understanding of TCBPA exposure-associated ROS accumulation. [ABSTRACT FROM AUTHOR]

Air pollution is an important trigger of cardiovascular disease worldwide, but few studies have determined the cardiovascular disease, health, and economic burdens attributable to ambient carbon monoxide (CO). This study aimed to examine the association between CO and CVD hospitalizations, and quantified the attributable CVD hospitalizations, associated hospital stays and hospitalization costs for CO in Lanzhou, one of the most air-polluted Chinese cities historically. Daily data on CVD hospitalizations, air pollutants, and weather records from 2013 to 2017 were obtained for Lanzhou, China. Generalized additive model with a quasi-Poisson link was used to model the association between CO and CVD hospitalizations, after controlling for other air pollutants, weather conditions, day of week, long-term trend, influenza and pneumonia incidence. The effects of CO on hospital stays and hospitalization expenses from CVD were also quantified. CO concentrations below the current Chinese ambient air quality standard had a significant impact on CVD hospitalizations. Each 1 mg/m3 increase in CO concentration on the present day and previous 4 days (lag 0–4) was associated with an 11% (95% confidence interval: 3%–20%) increase in total CVD hospitalizations. During the study period, CO was responsible for 11.74% of total CVD hospitalizations, equating to 62,792 inpatient days and 149 million RMB. Each adult patient on average spent approximately 5% of annual salary on medicine from CO-related CVD treatment during hospitalization. Maintaining the historical CO concentration within 1 to 3 mg/m3 could avert hundreds of total CVD hospitalizations and save millions of RMB annually in Lanzhou, China. Exposure to low-level ambient CO concentration increased the risk of CVD hospitalizations and resulted in substantial health and economic burdens in Lanzhou, China. Our findings can be used for evidence-based practice and policy making to assess the cost-effectiveness of prevention measures. Unlabelled Image • We estimated the disease, health, and economic burdens of carbon monoxide (CO) on CVD. • Exposure to low-level CO still had adverse effects on CVD hospitalizations in Lanzhou, China. • Low-level CO caused substantial CVD hospitalizations, hospital stays, and hospitalization expenses. • Each adult patient spent around 5% of annual salary on medicine for CO-related CVD treatment. • Further control of CO could prevent massive CVD hospitalizations and save millions RMB annually. [ABSTRACT FROM AUTHOR]

Abstract In this work, the microstructures and mechanical properties of as-cast Mg-xHo-2Zn (x = 4, 6 and 8 wt%) alloys have been studied by using optical microscope (OM), X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM) and tensile test at different temperatures. The Ho element exhibits an influence on the grain refinement of the alloys. Increasing Ho content promotes the formation of long period stacking ordered (LPSO) structure, which changes the mechanical properties of the alloys. As a consequence, the strength of the alloy rises with the increase of Ho addition at room temperature and elevated temperature. However, the elongation of the alloy increases at room temperature but slightly decreases at high temperature when the Ho addition increases. These results are explained from morphology evolution of W-phase and the presence of LPSO phase in different alloys. Highlights • The increasing Ho additions promote the grain refinement of the alloys. • The increasing Ho contents results in the formation of 18R-LPSO structure. • Ho contents change the mechanical property of the alloys at high temperature. [ABSTRACT FROM AUTHOR]

Digital literacy is a crucial skill for accessing the benefits of the digital economy. Analyzing the impact of digital literacy on the risk of falling back into poverty is of great practical significance for achieving sustainable poverty alleviation. Based on data from the China Family Panel Studies (CFPS) in 2018, this paper examines the impact of digital literacy on the risk of returning to poverty for poverty-alleviated households, and investigates its underlying mechanism. The study finds that digital literacy can reduce the risk of returning to poverty by promoting local non-farm employment and migrant work, improving entrepreneurial performance, and expanding entrepreneurial scale. However, digital literacy plays a relatively minor role in reducing the risk of returning to poverty through entrepreneurship compared to employment. In the heterogeneity analysis, this paper concludes that digital literacy is more advantageous for disadvantaged groups. Furthermore, compared to digital entertainment literacy, digital learning literacy is more effective in reducing the risk of returning to poverty. This study has significant implications for understanding and improving the governance mechanism of sustainable poverty alleviation through digital literacy. • Digital literacy can reduce the risk of returning to poverty. • Employment and entrepreneurship are both essential mechanism for reducing the risk of returning to poverty. • Employment plays a more significant role of mechanism than entrepreneurship. • Disadvantaged households benefit more from digital literacy. [ABSTRACT FROM AUTHOR]