Numerical and experimental analysis on green laser crystallization of amorphous silicon thin films

The laser fluence effect on crystallization of amorphous silicon irradiated by a frequency-doubled Nd: YAG laser has been studied both theoretically and experimentally. An effective numerical model is set up to predict the melting threshold and the optimized laser fluence for crystallization of 200nm amorphous silicon. Temperature distribution with time and melt depth are analyzed. Besides the model, Raman spectra of thin films treated with different fluences are measured to confirm the phase transition and to determine the optimized fluence. The calculating results accord well with those obtained from the experimental data in this research

How do online users perceive health risks during public health emergencies? Empirical evidence from China

BackgroundThe global COVID-19 pandemic has posed a major threat to human life and health, and new media technologies have intensified the spread of risk perception.PurposeThis study aimed to explore the impact of risk information ground on online users’ perceived health risks, and further explore the mediating role of psychological distance and the moderating role of self-efficacy.MethodsA total of 25 Internet users from different provinces in China were interviewed in-depth, NVIVO.11 was used to qualitatively analyze the interview text data and construct a theoretical model. A total of 492 interviewees were recruited in order to complete a scenario questionnaire, SPSS-27 was used to perform orthogonal experiments, generate eight combinatorial scenarios, analyze demographic data, and clean and prepare data for testing hypotheses. SmartPLS 3.0 was used to test the conceptual model using the structural equation model (SEM) of the partial least squares (PLS).ResultsThe analysis of the SEM model shows that all planned hypotheses (Information fluency → Information diagnosability, Information extensibility → Information diagnosability, Information diagnosability → Psychological distance, Platform interactivity → Scenario embeddedness, Network connectivity → Scenario embeddedness, Scenario embeddedness → Psychological distance, Psychological distance → Risk perception, Psychological distance → Self-efficacy → Risk perception, Information fluency → Information diagnosability → Psychological distance → Risk perception, Information extensibility → Information diagnosability → Psychological distance → Risk perception, Platform interactivity → Scenario embeddedness → Psychological distance → Risk perception, Network connectivity → Scenario embeddedness → Psychological distance → Risk perception) are confirmed.ConclusionThis study found that the information ground factors significantly affect online users’ perceptions of health risks, psychological distance mediates the effect of information ground factors on risk perception, and self-efficacy negatively moderates the effect of psychological distance on risk perception

Affirmative action in education and Black Economic Empowerment in the workplace in South Africa since 1994: policies, strengths and limitations

This paper explains the concepts of Affirmative Action (AA) and Black Economic Empowerment (BEE) and the policies developed in post-Apartheid South Africa. It compares it to similar policies adopted in different contexts in Malaysia, India and the U.S.A. It explains and critiques the South African policies on AA and BEE, its history since 1994 and how class has replaced race as the determinant of who succeeds in education and the workplace. It analyses why these policies were essential to address the massive racial divide in education and the workplace at the arrival of democracy in 1994, but also why it has been controversial and racially divisive. The strengths and limitations of these policies are juxtaposed, the way it has benefitted the black and white elites, bolstered the black middle-class but has had little success in addressing the education and job futures of poor, working class black citizens in South Africa. The views of a number of key social analysts in the field are stated to explain the moral, racial, divisive aspects of AA in relation to the international experience and how South Africa is grappling with limited success to bridge the divide between the rich and poor

Comprehensive phenotypic analysis and quantitative trait locus identification for grain mineral concentration, content, and yield in maize (Zea mays L.)

Biofortification by enhanced mineral density in maize grain through genetic improvement is one of the efficient ways to solve global mineral malnutrition, in which one key step is to detect the corresponding Quantitative Trait Loci (QTL). In this work, a maize recombinant inbred population (RIL) was grown to maturity in four field environments with two locations × two years. Phenotypic data of mineral nutrition concentration, content and yield were determined for grain copper (Cu), iron (Fe), manganese (Mn), zinc (Zn), magnesium (Mg), potassium (K) and phosphorus (P). Analysis of variance (ANOVA) showed significant effects of genotype, location and year for all investigated traits. Location showed the highest effect for all mineral yields, and Zn and Cu content and concentration, while year had the strongest impact for Mn, K, and P content and concentration. Heritabilities (h2) of different traits varied with higher h2 (72-85%) for mineral concentration and content and lower (48-63%) for nutrient yields. Correlation coefficient analysis revealed significant positive correlations for grain concentration between several minerals. P had the closest correlations to other elements, while Cu had the lowest. When environments were analyzed individually, a total of 28, 25, and 12 QTL were identified for nutrient concentration, content and yield, respectively. Among these QTL, 8 QTL were consistent within traits across different environments. These stable QTL may be most promising for controlling mineral accumulation in maize grain. Co-localization of QTL for different traits was found for 12 chromosome regions, suggesting that common processes might contribute seed nutrient accumulatio

DLX3 Inhibits the Proliferation of Human Dental Pulp Cells Through Inactivation of Canonical Wnt/β-Catenin Signaling Pathway

Homeodomain gene Distal-less-3 (Dlx3) plays an important role during tooth development. Our previous studies indicate that DLX3 inhibits proliferation of human dental pulp cells (hDPCs). However, the mechanism of DLX3 regulating proliferation of hDPCs and maintaining the quiescence of the cells remain unknown. Given the importance of canonical Wnt signaling in the proliferation of dental pulp cell and tooth development, we hypothesized that DLX3 inhibited proliferation of hDPCs through inactivation of canonical Wnt signaling. With overexpression or knock-down of DLX3 in primary hDPCs, we found DLX3 down regulated canonical Wnt signaling and its downstream target genes. And when the DLX3 overexpressed-cells were treated with lithium chloride, the proliferation inhibition by DLX3 was reversed. We also found that DLX3 enhanced the expression of DKK1 and the reduced proliferation of hDPCs by DLX3 was reversed with knock-down of DKK1. Furthermore, luciferase reporter assay and chromatin immunoprecipitation assay showed DLX3 was able to bind to Dkk1 promoter region from nucleotides (nt) -1656 to -1245, and stimulated Dkk1 promoter activity. Mutagenesis studies further revealed two DLX3 responsive elements in Dkk1 promoter. Taken together, our data indicate that DLX3 inhibits proliferation of hDPCs via inactivation of Wnt/β-catenin signaling pathway by directly binding to Dkk1 promoter and increasing its expression

High Internal Phase Pickering Emulsion Stabilized by Natural Biomacromolecules and Its Application in Foods

In recent years, high internal phase Pickering emulsions (HIPPEs) has attracted much attention due to its unique organizational properties and has a wide application prospect in the food field. Natural biomacromolecules, active components in organisms, possess good biocompatibility, degradability, no or low toxic effects, which are excellent stabilizers for HIPPEs. In this paper, the potential of natural biomacromolecules to stabilize HIPPEs and recent progress on the application of biopolymer-stabilized HIPPEs in the inhibition of lipid oxidation, as a substitute for trans fatty acids, and in the encapsulation and delivery of nutrients, the 3D printing of foods and encapsulation of probiotics are briefly reviewed in order to provide a reference for the application of HIPPEs stabilized by natural biomacromolecules in foods