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China is currently experiencing a significant increase in the live-streaming industry, driven by high profitability and sales. The increasing prevalence of live-stream platforms has also contributed to the rise of influencers who possess larger fan bases and greater bargaining power. In the cosmetic sector, consumers often require firsthand experience with products in order to feel satisfied, which can create uncertainty in their purchase intentions. Live streaming is a recognised marketing strategy that allows firms to leverage the popularity of influencers to convert buying intentions into actual buying behaviour. This study aims to investigate the factors that influence consumer purchase intention in relation to influencer popularity. This study aims to investigate the mediating role of perceived enjoyment and uncertainty, as well as the moderating role of product information, in the relationship between influencer popularity and purchase intention. This study expands the existing knowledge of the S-O-R model by gathering data from Taobao live streaming. The collected data was analysed using SPSS version 26 and structural equation modelling (SEM) with SmartPLS 3.3.9. The study's findings indicate that the impact of influencer popularity on consumer buying intention is partially mediated by perceived uncertainty and perceived enjoyment. Furthermore, studies have demonstrated the significant moderating role of the quality of product information. The results suggest that cosmetic companies should offer comprehensive product information to influencers when showcasing their products during live streaming events. The live streaming industry can enhance product preparation and information dissemination for online marketing. [ABSTRACT FROM AUTHOR]

High-power electromagnetic pulses can transmit a large induced electromotive force or energy through metal interconnection lines, causing interference or damage to integrated circuits. CMOS circuits are the basic components of sensors, so sensors that work in an electromagnetic environment may malfunction. It is of great importance to study the antielectromagnetic damage technology of CMOS inverters. On the basis of the simulation using Sentaurus, an electrothermal coupling model of a 55 nm CMOS inverter is established. The simulation results show that the latch-up effect is the main mechanism of CMOS failure. In view of the failure process under different high-power microwave (HPM) pulse parameters, we propose a CMOS inverter reinforcement technology. Research shows that the source injection current of the reinforced structure is more than ten times less than that of the traditional structure under electromagnetic interference, which effectively suppresses the occurrence of latch-up. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effect of aging on the color stability and bond strengths of dual-cured resin cements containing amine or amine-free self-initiators. Three dual-cured and one light-cured resin cements were used. The covered (by lithium disilicate ceramic disks) and uncovered groups (n=10) were included. Color measurements were tested after 24 h, 10,000 and 20,000 thermal cycles (TCs). Micro-shear bond strengths (µSBS) were tested after 24 h, 10,000 and 20,000 TCs, and failure modes were analyzed (n=14). Two-way ANOVA and Tukey's test were implemented for color difference (ΔE*ab) and µSBS (α=0.05). The mean ΔE*ab difference was significant among groups (p<0.001). The lowest ΔE*ab values were obtained for dual-cured resin cement with aminefree self-initiators dual-cured cement after aging in all dual-cured resin cements, and the µSBS of the dual-cured resin cements on ceramic was significantly higher than that of the light-cured ones after aging (p<0.001). [ABSTRACT FROM AUTHOR]

Intermediate-volatility organic compounds (IVOCs) emitted from vehicles are important precursors to secondary organic aerosols (SOA) in urban areas, yet vehicular emission of IVOCs, particularly from on-road fleets, is poorly understood. Here we initiated a field campaign to collect IVOCs with sorption tubes at both the inlet and the outlet in a busy urban tunnel (>30,000 vehicles per day) in south China for characterizing emissions of IVOCs from on-road vehicles. The average emission factor of IVOCs (EFIVOCs) was measured to be 16.77 ± 0.89 mg km[sup -1] (Average ± 95% C.I.) for diesel and gasoline vehicles in the fleets, and based on linear regression the average EFIVOCs was derived to be 62.79 ± 18.37 mg km-1 for diesel vehicles and 13.95 ± 1.13 mg km[sup -1] for gasoline vehicles. The EFIVOCsfor diesel vehicles from this study was comparable to that reported previously for non-road engines without after-treatment facilities, while the EFIVOCsfor gasoline vehicles from this study was much higher than that recently tested for a China V gasoline vehicle. IVOCs from the on-road fleets did not show significant correlation with the primary organic aerosol (POA) or total non- methane hydrocarbons (NMHCs) as results from previous chassis dynamometer tests. Estimated SOA production from the vehicular IVOCs and VOCs surpassed the POA by a factor of ~ 2.4, and IVOCs dominated over VOCs in estimated SOA production by a factor of ~ 7, suggesting that controlling IVOCs is of greater importance to modulate traffic-related OA in urban areas. The results demonstrated that although on-road gasoline vehicles have much lower EFIVOCs, they contribute more IVOCs than on-road diesel vehicles due to its dominance in the on- road fleets. However, due to greater diesel than gasoline fuel consumption in China, emission of IVOCs from diesel engines would be much larger than that from gasoline engines, signaling the overwhelming contribution of IVOC emissions by non-road diesel engines in China. [ABSTRACT FROM AUTHOR]

Many studies have recently been done on understanding the sources and formation mechanisms of atmospheric aerosols at ground level. However, vertical profiles and sources of size-resolved particulate matter within the urban boundary layer are still lacking. In this study, vertical distribution characteristics of size-segregated particles were investigated at three observation platforms (ground level, 118 m, and 488 m) on the 610m high Canton Tower in Guangzhou, China. Size-segregated aerosol samples were simultaneously collected at the three levels in autumn and winter. Major aerosol components, including water-soluble ions, organic carbon, and elemental carbon, were measured. The results showed that daily average fine-particle concentrations generally decreased with height. Concentrations of sulfate and ammonium in fine particles displayed shallow vertical gradients, and nitrate concentrations increased with height in autumn, while the chemical components showed greater variations in winter than in autumn. The size distributions of sulfate and ammonium in both seasons were characterized by a dominant unimodal mode with peaks in the size range of 0.44--1.0 µm. In autumn, the nitrate size distribution was bimodal, peaking at 0.44--1.0 and 2.5--10 µm, while in winter it was unimodal, implying that the formation mechanisms for nitrate particles were different in the two seasons. Our results suggest that the majority of the sulfate and nitrate is formed from aqueous-phase reactions, and we attribute coarse-mode nitrate formation at the measurement site to the heterogeneous reactions of gaseous nitric acid on existing sea-derived coarse particles in autumn. Case studies further showed that atmospheric aqueous-phase and heterogeneous reactions could be important mechanisms for sulfate and nitrate formation, which, in combination with adverse weather conditions such as temperature inversion and calm wind, led to haze formation during autumn and winter in the Pearl River Delta (PRD) region. [ABSTRACT FROM AUTHOR]

Black carbon (BC) is an important climate forcer in the atmosphere. Amplification of light absorption can occur by coatings on BC aerosols, an effect that remains one of the major sources of uncertainties for accessing the radiative forcing of BC. In this study, the absorption enhancement factor (Eabs) was quantified by the minimum R squared (MRS) method using elemental carbon (EC) as the tracer. Two field campaigns were conducted in urban Guangzhou at the Jinan university super site during both wet season (July 31-September 10, 2017) and dry season (November 15, 2017-January 15, 2018) to explore the temporal dynamics of BC optical properties. The average concentration of EC was 1.94 ± 0.93 and 2.81 ± 2.01 μgC m-3 in the wet and dry seasons, respectively. Mass absorption efficiency at 520 nm by primary aerosols (MAEp520) determined by MRS exhibit a strong seasonality (8.6 m2g-1 in the wet season and 16.8 m2g-1 in the dry season). Eabs520 was higher in the wet season (1.51 ± 0.50) and lower in the dry season (1.29 ± 0.28). Absorption Ångström exponent (AAE470-660) in the dry season (1.46 ± 0.12) were higher than that in the wet season (1.37 ± 0.10). Collective evidence showed that the active biomass burning (BB) in dry season effectively altered optical properties of BC, leading to elevated MAE, MAEp and AAE in dry season comparing to those in wet season. Diurnal Eabs520 was positively correlated with AAE470-660 (R2 = 0.71) and negatively correlated with the AE33 aerosol loading compensation parameter (k) (R2 = 0.74) in the wet season, but these correlations were significantly weaker in the dry season, which may be related to the impact of BB. This result suggests that lensing effect was dominating the AAE diurnal variability during the wet season. The effect of secondary processing on Eabs diurnal dynamic were also investigated. The Eabs520 exhibit a clear dependency on secondary organic carbon to organic carbon ratio (SOC/OC). Eabs520 correlated well with nitrate, implying that gas-particle partitioning of semi-volatile compounds may potentially play an important role in steering the diurnal fluctuation of Eabs520. In dry season, the diurnal variability of Eabs520 was associated with photochemical aging as evidenced by the good correlation (R2 = 0.69) between oxidant concentrations (Ox=O3+NO2) and Eabs520. [ABSTRACT FROM AUTHOR]

Great progress has been made recently in the understanding of the sources and formation mechanisms of atmospheric aerosols at the ground level. However, vertical profiles and sources of size-resolved particulate matter within the urban boundary layer are still lacking. In this study, vertical distribution characteristics of size-segregated particles were investigated at three observation platforms (ground, 118 m and 488 m) on the 610-meter-high Canton Tower in Guangzhou, China. Size-segregated aerosol samples were simultaneously collected at the three levels on the Canton Tower in autumn and winter, respectively. Major aerosol components, including water-soluble ions, organic carbon and elemental carbon, were measured. The results showed that daily average fine-particle concentrations generally decreased with height. Concentrations of sulfate and ammonium in fine particles displayed small vertical gradients and nitrate concentrations increased with height in autumn, while the above chemical components showed greater variations in winter than in autumn. The size distributions of sulfate and ammonium in both seasons were characterized by dominant unimodal droplet modes with a peak at the size range of 0.44–1.0 μm. In autumn, the nitrate size distribution was bi-modal, peaking at 0.44–1.0 μm and 2.5–10 μm, while it was unimodal in winter, implying that the formation mechanisms for nitrate particles were different in the two seasons. Our results suggest droplet mode sulfate and nitrate are likely formed from aqueous-phase reactions and coarse mode nitrate formation is attributed to heterogeneous reactions of gaseous nitric acid on existing sea-derived coarse particles in autumn at the measurement site. The results from pollution cases study further showed that atmospheric aqueous-phase and heterogeneous reactions together with adverse weather conditions, such as temperature inversion and calm wind, resulted in the autumn and winter haze pollution in the PRD region. [ABSTRACT FROM AUTHOR]

The degradation mechanism of Ti/Pt/Au ohmic contacts to p-GaAs was identified experimentally under high direct-current density stress in detail. A revised measuring structure was designed based on the circular transfer length method (CTLM), in which the high current density of 0.8 × 105 A/cm2 was applied vertically, while the contact resistance was measured horizontally between two contact electrodes. According to revised CTLM, the specific contact resistance was measured during stress. The results indicated that specific contact resistance showed an exponential dependence on the aging time. The depth profiling results obtained from the Auger electron spectroscopy showed that Pt penetrated into the Au layer during stress. Furthermore, some voids were observed at the Au/Pt interface, and intermixing began to form within metal layer during stress. These results demonstrated that the degradation of Ti/Pt/Au ohmic contacts to p-GaAs was attributed mainly to the electromigration and Joule heating along the current direction under high current density. [ABSTRACT FROM PUBLISHER]

Background: Bladder cancer is the sixth most common cancer in the world and the incidence is particularly high in southwestern Taiwan. Previous studies have identified several tumor-related genes that are hypermethylated in bladder cancer; however the DNA methylation profile of bladder cancer in Taiwan is not fully understood. Methods: In this study, we compared the DNA methylation profile of multiple tumor suppressor genes (APC, DAPK, E-cadherin, hMLH1, IRF8, p14, p15, RASSF1A, SFRP1 and SOCS-1) in bladder cancer patients from different Chinese sub-populations including Taiwan (104 cases), Hong Kong (82 cases) and China (24 cases) by MSP. Two normal human urothelium were also included as control. To investigate the diagnostic potential of using DNA methylation in non-invasive detection of bladder cancer, degree of methylation of DAPK, IRF8, p14, RASSF1A and SFRP1 was also accessed by quantitative MSP in urine samples from thirty bladder cancer patients and nineteen non-cancer controls. Results: There were distinct DNA methylation epigenotypes among the different sub-populations. Further, samples from Taiwan and China demonstrated a bimodal distribution suggesting that CpG island methylator phentotype (CIMP) is presented in bladder cancer. Moreover, the number of methylated genes in samples from Taiwan and Hong Kong were significantly correlated with histological grade (P < 0.01) and pathological stage (P < 0.01). Regarding the samples from Taiwan, methylation of SFRP1, IRF8, APC and RASSF1A were significantly associated with increased tumor grade, stage. Methylation of RASSF1A was associated with tumor recurrence. Patients with methylation of APC or RASSF1A were also significantly associated with shorter recurrence-free survival. For methylation detection in voided urine samples of cancer patients, the sensitivity and specificity of using any of the methylated genes (IRF8, p14 or sFRP1) by qMSP was 86.7% and 94.7%. Conclusions: Our results indicate that there are distinct methylation epigenotypes among different Chinese subpopulations. These profiles demonstrate gradual increases with cancer progression. Finally, detection of gene methylation in voided urine with these distinct DNA methylation markers is more sensitive than urine cytology. [ABSTRACT FROM AUTHOR]