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The electronic and transport properties of fluorographane (C2HF) nanoribbons, i.e., bare (B-C2HF) and hydrogen-passivated (H-C2HF) C2HF nanoribbons, are extensively investigated using first-principles calculations. The results indicate that edge states are present in all the B-C2HF nanoribbons, which are not allowed in the H-C2HF nanoribbons regardless of the directions. The spin splitting phenomenon of band structure only appears in the zigzag direction. This behavior mainly originates from the dehydrogenation operation, which leads to sp2 hybridization at the edge. The H-C2HF nanoribbons are semiconductors with wide band gaps. However, the band gap of B-C2HF nanoribbons is significantly reduced. Remarkably, the phase transition can be induced by the changes in the magnetic coupling at the nanoribbon edges. In addition, the B-C2HF nanoribbons along the zigzag direction show optimal conductivity, which is consistent with the band structures. Furthermore, a perfect spin filtering controller can be achieved by changing the magnetization direction of the edge C atoms. These results may serve as a useful reference for the application of C2HF nanoribbons in spintronic devices.

Background According to the diagnosis criteria of the American Association of Endodontists (AAE), sensitive responses to cold and/or heat tests of suspected teeth compared with those of control teeth can be used for the diagnosis of pulpitis, but the role of electric pulp test (EPT) is not mentioned. It is believed that EPT has some limitations in determining the vitality of the pulp. The aim of this study was to explore the association between the difference in EPT values and the differential diagnoses of reversible pulpitis (RP) and symptomatic irreversible pulpitis (SIRP) caused by dental caries. Methods A total of 203 cases with pulpitis caused by dental caries were included. A diagnosis of pulpitis was made on the basis of the diagnostic criteria of AAE. Patient demographic and clinical examination data were collected. The EPT values of the suspected teeth and control teeth were measured, and the differences between them were calculated. The correlation between the difference in the EPT values and diagnosis of pulpitis was analyzed using univariate and multivariate logistic regression. Results In the 203 cases (78 males and 125 females; 115 cases of RP, 88 cases of SIRP; 9 anterior teeth, 59 premolars, and 135 molars), the mean patient age was 34.04 ± 13.02 (standard deviation) years. The unadjusted (crude) model, model 1 (adjusted for age), model 2 (adjusted for age and sex), and model 3 (adjusted for age, sex, and tooth type) were established for the statistical analyses. In model 3 [odds ratio (OR) = 1.025; 95% confidence interval (CI) 1.002–1.050; P = 0.035], the difference in EPT values between RP and SIRP was statistically significant. However, the areas under the curve of predictive probability of the crude model, model 1, model 2, and model 3 were 0.565, 0.570, 0.585, and 0.617, respectively, showing that the model accuracy was low. The P-value for the trend in differences between the EPT values as a categorical variable showed that the differences in the EPT values, comparing RP and SIRP, were not statistically significant. Conclusions Based on the present data, the difference in EPT values was not sufficient to differentiate RP from SIRP.

When humans are confronted with an epidemic situation or a continuous natural disaster, success depends largely on how critical information is conveyed to as many people as possible, how individuals' emotional experiences of the crisis are elicited, and how their behaviors are directed going forward. Efficient publicity is key to successful epidemic prevention and control. This study explores the role of creative publicity by comparing the influence of creative publicity and general publicity in different periods of the COVID-19 outbreak in China. The effects of creative and general publicity differed across varying periods of the COVID-19 outbreak. Specifically, compared to general publicity, creative publicity had a significant impact on individuals' emotional arousal in the early period of the COVID-19 outbreak while it significantly promoted individuals' emotional arousal, behavioral regulation, and willingness to actively disseminate information in the middle period. In the stable period of the COVID-19 outbreak, creative publicity performed better than general publicity in regulating individuals' behavior. On the other hand, general publicity was more effective than creative publicity in regulating individuals' behavior and actively disseminating information about the epidemic in the early period of the COVID-19 outbreak. In conclusion, creative and general publicity had differing effects in different periods of the COVID-19 outbreak, which may relate to the characteristics of the publicity format and people's psychological conditions in different periods of the COVID-19 outbreak.

The electronic, transport, and optoelectronic properties of monolayer black phosphorus (MLBP) are much influenced by grafting PdCl2 groups, demonstrated here by using density functional theory (DFT) and non-equilibrium Green's function (NEGF) as well as the Keldysh Nonequilibrium Green's Functions (KNEGF) methods. We find that the PdCl2 groups prefer to locate over the furrow site of MLBP and form a planar quadridentate structure of . The PdCl2 groups serve as quantum dots by introducing discrete flat levels between the MLBP valence band and the Fermi level (Ef). The conductivity is much lowered after attaching PdCl2 quantum dots, due to the fact that the scattering effect of PdCl2 plays a major role in the process of electron transporting. A threshold voltage is found for the functionalized system with a large density of PdCl2 quantum dots, a valuable clue for exploring current switches. However, no evident threshold voltage is found for the pure MLBP. Electrons permeate easier through the armchair direction compared with the zigzag either in the pure MLBP or in the functionalized composites. More importantly, grafting PdCl2 quantum dots is very beneficial for enhancing photoresponse. The values of photoresponse for the modified species are about 20 times higher than the free MLBP. A significant photoresponse anisotropy is observed for both MLBP and nPdCl2-BP (n = 1, 2, and 4), contrary to the conductivity, the zigzag direction shows much stronger photoresponse than the armchair. All of the aforementioned unique properties make these new two-dimensional (2D) MLBP based materials especially attractive for both electronic and optoelectronic devices.

To combat pollution, the Chinese government has taken a series of environmental regulations, including requiring cities to report their daily air quality information. This has affected not only the environmental performance of governments and enterprises but also individual happiness. This paper attempts to explore whether and how mandatory air quality information disclosure affects happiness in China, using a difference-in-differences (DID) approach across cities for the waves 2007, 2008 and 2013. Empirical results show that in Chinese cities, people feel less happy over time although there is an increase in GDP per capita. Moreover, it is found that mandatory air pollution index (API) disclosure exerts a significantly positive impact on happiness, mainly by reducing air pollution. Our analysis has policy implications that for developing countries, air quality information disclosure should be encouraged since it is effective in combating air pollution resulting from high economic development and meanwhile it adds to individual happiness.

Introduction This study examined the identity of the microbiome of deep dentinal caries and its correlation with the inflammation status of caries-induced pulpitis. Methods Seventy-five cases were diagnosed based on the American Association of Endodontics's diagnostic criteria and divided into 4 groups: normal pulp with deep caries (NP; n = 13), reversible pulpitis with only cold-evoked pain (CRP; n = 17), reversible pulpitis with both cold/heat-evoked pain (CHRP; n = 24), and symptomatic irreversible pulpitis (SIP; n = 21). Samples were sequenced by 16S rDNA. Alpha and beta diversity were determined. Linear discriminant analysis effect size (LEfSe) analysis was used to detect intergroup differences, and receiver operating characteristic (ROC) curves were generated to assess the role of the caries microbiome in caries-induced pulpitis. Results The 16S rDNA sequencing yielded 9100 operational taxonomic units. Lactobacillus had the highest relative abundance at the genus level among the 4 groups. There were significant differences in the distribution of the microbiome among the groups. In an alpha diversity analysis, species richness differed between the CRP group and the other groups. In a beta diversity analysis, the distribution of microorganisms in the SIP group was significantly different from those in the other 3 groups. LEfSe analysis indicated substantial differences in the microbiome among the groups, and the areas under the ROC curves (AUC) were all high (AUC: 0.734–0.952). Conclusions Characterization of the caries microbiome has the potential to become an auxiliary method for the diagnosis of pulpitis. This finding may prompt new research on diagnostic strategies for caries-induced pulpitis.

An improved classification of Oolong tea with different varieties is presented combining two novel artificial sensing tools (i.e. gustatory sensors and olfactory sensors). Herein, the gustatory sensors system was developed by using four electrodes (gold, copper, platinum and glassy carbon) in a standard three-electrode configuration, and the olfactory sensors system was developed based on a colorimetric sensors array. Initially, the data obtained from the two sensor systems was analyzed separately. Then, the potential of the combination of two sensors systems for classification was investigated. Principal component analysis (PCA) and linear discriminant analysis (LDA), as two classification tools, were used for data classification. The results show that the discrimination capability of the combined system is superior to that obtained with the two sensors systems separately, and eventually LDA achieved 100% classification rate by cross-validation. This work indicates that the combination of gustatory sensors system and olfactory sensors system can be a useful tool for the classification of Oolong tea with different varieties.

An improved classification of vinegar with different marked ages is presented using a combination of gustatory sensors and olfactory sensors. Herein, the gustatory sensor system is developed using four electrodes (gold, copper, platinum and glassy carbon) in a standard three-electrode configuration, and the olfactory system is developed based on a colorimetric sensor array. Initially, the data obtained from the two sensor systems were analyzed separately. Then, the potential of the combination of the two sensor systems for classification is investigated. Principal component analysis (PCA) and linear discriminant analysis (LDA), as two classification tools, are used for data classification. The results show that the capability of discrimination of the combined system is superior to that obtained with the two sensor systems separately, and eventually LDA achieved 100% classification rate by cross-validation. This work indicates that the combination of gustatory sensor systems and olfactory sensor systems can be a useful tool for the classification of vinegar with different marked ages.

Security has become an important issue in Web Services application, which has been widely concerned. This paper introduces several security policy models that widely applied and analyzes the basic principles. And then a simple comparison was made for the scope and merits of these models, finally this paper points out the Web Services security research.