Achieving excellent esthetics with monolithic self-glazed zirconia crowns in anterior teeth is challenging, and the impact of different surface treatments and abutment shades on the final color is ...unclear.
The purpose of this in vitro study was to evaluate the effects of different external surface treatments (self-glazed, milled, polished, and glazed), different intaglio surface treatments (milled and airborne-particle abraded), and different abutment shades on the color difference of high-translucency self-glazed zirconia crowns.
Sixty shade A1 and 60 shade A3 crowns were fabricated with a thickness of 0.80 ±0.02 mm and randomly divided into 12 groups (n=10). Different external and intaglio surface treatments were applied. Shade A1 and A3 abutments were made with composite resin. Color was measured with a spectrophotometer and expressed in CIELab coordinates, and color differences (ΔE00) between specimens and references were calculated. The data were analyzed with ANOVA and the Tukey post hoc test. The impact of different surface treatments and abutment shades on the color difference were compared by using multiple linear regression (α=.05).
The effects of external surface treatments, intaglio airborne-particle abrasion, and abutment shades on the L∗, a∗, b∗ and ΔE00 values of the final color of the crowns were significantly different (P<.001). Polishing resulted in the greatest ΔE00 value among all external surface treatments (P<.001). The average ΔE00 values of all crowns on the A3 abutment were higher than those of all crowns on the A1 abutment (P<.001). The influence on the color difference was abutment>external surface treatment>intaglio surface treatment.
Different surface treatments affected the final color of zirconia crowns, and a greater impact was seen with external surface treatments than with intaglio surface treatments. External polishing resulted in the greatest color difference. The abutment shade had the most effect on the color difference, as the darker the abutment color, the greater the color difference.
A solar home system (SHS), containing three independent parts, namely a load voltage dc–dc converter, an energy storage device (ESD) charger, and an ESD equalizer, will become bulky and costly. Thus, ...based on Cuk converter, an integrated charging equalizing converter (ICEC) is proposed. The ICEC can achieve load voltage converting, battery/supercapacitor (SC) charging, and equalizing simultaneously. The idea of the ICEC is using a voltage multiplier (VM) to replace the capacitor in Cuk convertor, and then reusing the VM as a charging equalizer. When the Cuk converter is operating, the voltage ripple generated on the VM, which can be regarded as an ac voltage source, is utilized to drive the VM. Therefore, compared with the traditional methods, the charging and equalizing can be achieved without extra switches and magnetic elements. A prototype for four SCs is built to verify the feasibility of the proposed method. And the system efficiency is 87%, corresponding to the input power 5.6 W, the load output power 3.54 W, and the charging balance power 1.33 W. Moreover, a quantitative comparison shows the proposed method can reduce the system size and cost effectively.
A solar home system (SHS), containing three independent parts, namely a load voltage dc–dc converter, an energy storage device (ESD) charger, and an ESD equalizer, will become bulky and costly. Thus, based on the Cuk converter, an integrated charging equalizing converter (ICEC) is proposed. The ICEC can achieve load voltage converting, battery/supercapacitor (SC) charging, and equalizing simultaneously. The idea of the ICEC is using a voltage multiplier (VM) to replace the capacitor in Cuk convertor, and then reusing the VM as a charging equalizer. When the Cuk converter is operating, the voltage ripple generated on the VM, which can be regarded as an ac voltage source, is utilized to drive the VM. Therefore, compared with the traditional methods, the charging and equalizing can be achieved without extra switches and magnetic elements.
This study examined the correlations between trust in government and the public's protective behaviors regarding food safety, focusing on the mediating role of risk perception.
The 2013 (1,432 ...samples) and 2019 (1,276 samples) Taiwan Social Change Survey data were analyzed using ordinary least squares regression models. The bootstrap method was used to examine the mediating effect of risk perception.
Perceived integrity of government regarding food safety issues influences all four types of food protective behaviors directly and indirectly
risk perceptions. The four protective behaviors were "not eating that food," "preparing food kit," "preferring organic food," and "overall behaviors." Trust in government directly influences part of the protective food behaviors, while no mediating effects of risk perception were found.
The results of this study will deepen our understanding of food consumption behavior, identify key factors that influence public food protective behaviors, and inform food safety management to implement strategies necessary to improve food consumption.
Mindfulness-based interventions are found to have a positive effect on an individual's mental health. Using a meta-analysis method, this study examined the effects of mindfulness-based interventions ...on alleviating anxiety among Chinese college students. Using six international and two Chinese electronic databases, we comprehensively researched literature published between 1 January 2012 and 31 December 2021. The literature was then carefully selected and classified. The literature selection, data extraction, and quality assessment were all independently conducted by two members of the research team; any disagreements were resolved through consultation with a third researcher. A total of 11 original articles met all the eligibility criteria and were included in the meta-analysis. The meta-analysis revealed that mindfulness-based interventions have a positive effect on the remission of anxiety among Chinese college students. This confirms the need to generalize mindfulness-based interventions as a form of treatment and prevention for anxiety among Chinese college students.
Aryl phosphorus-containing flame retardants (aryl-PFRs) have been frequently detected with increasingly used worldwide as one of alternatives for brominated flame retardants. However, information on ...their adverse effects on human health and ecosystem is insufficient, with limited study on their molecular mode of action in vitro. In this study, the cytotoxicity, DNA damage, mitochondrial impairment and the involved molecular mechanisms of certain frequently detectable aryl-PFRs, including 2-ethylhexyldiphenyl phosphate (EHDPP), methyl diphenyl phosphate (MDPP), bisphenol-A bis (diphenyl phosphate) (BDP), isodecyl diphenyl phosphate (IDPP), cresyl diphenyl phosphate (CDP) and the structurally similar and widely used organophosphorus pesticide chlorpyrifos (CPF), were evaluated in A549 cells using high-content screening (HCS) system. Aryl-PFRs showed different lethal concentration 50 (LC50) values ranging from 97.94 to 546.85 μM in A549 cells using CCK-8 assay. EHDPP, IDPP, CDP, MDPP and CPF demonstrated an ability to induce DNA damage, evidenced by increased DNA content and S phase-reducing cell cycle arrest effect using fluorophore dye cocktail assay. Additionally, the selected aryl-PFRs induced mitochondrial impairment by the increasing mitochondrial mass and decreasing mitochondrial membrane potential. Moreover, BDP, MDPP, and CDP, which contain short alkyl chains showed their potential oxidative stress with intracellular ROS and mitochondrial superoxide overproduction from an initially relatively low concentration. Additionally, based on the promotion of firefly luminescence in p53-transfected A549 cells, p53 activation was found to be involved in aryl-PFRs-induced DNA damage. Further real-time PCR results showed that all selected aryl-PFRs triggered p53/p21/gadd45β-, and p53/p21/mdm2-mediated cell cycle pathways, and the p53/bax mediated apoptosis pathway to induce DNA damage and cytotoxic effects. These results suggest that aryl-PFRs (e.g., BDP, MDPP, CDP) cause oxidative stress-mediated DNA damage and mitochondrial impairment, and p53-dependent pathway was involved in the aryl-PFRs-induced DNA damage and cell cycle arrest. In conclusion, this study improves the understanding of PFRs-induced adverse outcomes and the involved molecular mechanism.
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•The cytotoxicity, DNA damage, and mitochondrial impairment induced by aryl-PFRs were evaluated.•Aryl-PFRs induced oxidative stress-mediated DNA and mitochondrial damage.•EHDP, IDPP, CDP, MDPP and CPF exerted S phase cell ratio-reducing effects.•p53 pathway activation is an underlying mechanism of the induced DNA damage.•Cytotoxicity was evidenced by the upregulation of the p53/bax-mediated apoptosis pathway.
Asymptotic synchronization requires continuous external control of the system, which is unrealistic considering the cost of control. Adaptive control methods have strong robustness to uncertainties ...such as disturbances and unknowns. On the other hand, for finite-time synchronization, if the initial value of the system is unknown, the synchronization time of the finite-time synchronization cannot be estimated. This paper explores the finite-time adaptive synchronization (FTAS) and fixed-time synchronization (FDTS) of fractional-order memristive cellular neural networks (FMCNNs) with time-varying delays (TVD). Utilizing the properties and principles of fractional order, we introduce a novel lemma. Based on this lemma and various analysis techniques, we establish new criteria to guarantee FTAS and FDTS of FMCNNs with TVD through the implementation of a delay-dependent feedback controller and fractional-order adaptive controller. Additionally, we estimate the upper bound of the synchronization setting time. Finally, numerical simulations are conducted to confirm the validity of the finite-time and fixed-time stability theorems.
In this article, we discussed the fixed-time synchronization of fractional-order memristor-based fuzzy cellular neural networks (FMFCNNs) with time-varying delays. Based on the differential inclusion ...theory and discontinuous state feedback control technique, some useful novel criteria of the fixed-time synchronization for FMFCNNs are derived by constructing appropriate Lyapunov function. The results in our paper improve and generalize current literature research results significantly. Finally, the effectiveness of our control schemes for the fixed-time synchronization is demonstrated through numerical simulations.
The wear behaviors of a newly developed grade of self-glazed zirconia against the enamel of freshly extracted teeth were investigated under simulated oral stresses and chemical environment. It was ...revealed that an inherently formed enamel-like surface on self-glazed zirconia that is very smooth on micrometer scale yet with nanoscale roughness has almost the same frictional coefficient against tooth enamel as the well-polished zirconia surface. The wear scars observed on the worn surface of enamel against self-glazed zirconia and well-polished zirconia surface revealed that in both cases fatigue wear is the dominating wear mechanism. It was concluded that the friction and wear performances of both the well-polished and self-glazed zirconia ceramics against natural enamel were very similar, which bears a very strong implication for the clinical safe use of the full contour zirconia restorations, yet the self-glazed zirconia provides sufficiently improved aesthetic appearance that ensures its potential for direct clinical uses.
Based on the existing literature on government policy and crisis management, this article provides an internal-external and vertical-horizontal coordination framework with which to study coordination ...in a highly centralized regime. Four types of top-down crisis coordination are introduced to explain how resources fragmented among various sectors, regions, levels, and organizations are swiftly mobilized and deployed to support a strong crisis response. The article's analytical framework is applied to China's strategy to combat the COVID-19 pandemic. It shows how the sequence of coordinative action combined all four types of crisis coordination and how the coordinative measures co-exist in a hybrid and layered pattern, which enables highly centralized regimes to mobilize various resources across the country and achieve their final aim of crisis termination.
This paper investigates a class of finite-time synchronization problems of fractional order fuzzy inertial cellular neural networks (FFICNNs) with piecewise activations and mixed delays. First, the ...Caputo FFICNNs are established. A suitable transformation variable is constructed to rewrite FFICNNs with mixed delays into a first-order differential system. Secondly, some new effective criteria are constructed on the basis of the finite-time stability theory and Lyapunov functionals to realize the synchronization of the drive-response system. Finally, two numerical simulation examples show that the proposed method is effective.
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