Cost-effectiveness and cost-benefit analyses of fluoride varnish for caries prevention in Guangxi, China.

OBJECTIVES: The objectives of this study were to evaluate the cost-effectiveness and cost-benefit of fluoride varnish (FV) interventions for preventing caries in the first permanent molars (FPMs) among children in rural areas in Guangxi, China. METHODS: This study constituted a secondary analysis of data from a randomised controlled trial, analysed from a social perspective. A total of 1,335 children aged 6-8 years in remote rural areas of Guangxi were enrolled in this three-year follow-up controlled study. Children in the experimental group (EG) and the control group (CG) received oral health education and were provided with a toothbrush and toothpaste once every six months. Additionally, FV was applied in the EG. A decision tree model was developed, and single-factor and probabilistic sensitivity analyses were conducted. RESULTS: After three years of intervention, the prevalence of caries in the EG was 50.85%, with an average decayed, missing, and filled teeth (DMFT) index score of 1.12, and that in the CG was 59.04%, with a DMFT index score of 1.36. The total cost of caries intervention and postcaries treatment was 42,719.55 USD for the EG and 46,622.13 USD for the CG. The incremental cost-effectiveness ratio (ICER) of the EG was 25.36 USD per caries prevented, and the cost-benefit ratio (CBR) was 1.74 USD benefits per 1 USD cost. The results of the sensitivity analyses showed that the increase in the average DMFT index score was the largest variable affecting the ICER and CBR. CONCLUSIONS: Compared to oral health education alone, a comprehensive intervention combining FV application with oral health education is more cost-effective and beneficial for preventing caries in the FPMs of children living in economically disadvantaged rural areas. These findings could provide a basis for policy-making and clinical choices to improve children's oral health.

Projecting trends in the disease burden of adult edentulism in China between 2020 and 2030: a systematic study based on the global burden of disease.

Purpose: This study was based on the Global Burden of Disease (GBD) database and aimed to analyze the trend of disease burden for complete edentulism in Chinese adults between 1990 and 2030, and to provide valuable information for the development of more effective management and preventive measures. Methods: Data on Chinese adults with complete edentulism from 1990 to 2019 was analyzed using GHDx data. Descriptive analyses were used to analyze changes in the prevalence and burden of complete edentulism, gender and age distribution between 1990 and 2019. In addition, we used an autoregressive integrated moving average (ARIMA) model to predict the trend of disease burden for Chinese adults with complete edentulism between 2020 and 2030. Results: The incidence, prevalence, and rate of YLDs in adults with complete edentulism in China showed an increasing trend from 1990 to 2019. In 2019, the incidence was 251.20 per 100,000, the prevalence was 4512.78 per 100,000, and the YLDs were 123.44 per 100,000, marking increases of 20.58, 94.18, and 93.12% from 1990. Males experienced a higher increase than females. However, the standardized rates decreased over the same period. The ARIMA model predicts a subsequent upward and then downward trend for all indicators between 2019 and 2030, except for the standardized incidence rate which remained essentially unchanged. Specifically, the incidence is predicted to decrease from 388.93 to 314.40 per 100,000, prevalence from 4512.78 to 3049.70 per 100,000, and YLDs from 123.44 to 103.44 per 100,000. The standardized prevalence and YLDs rates are also expected to decrease. Conclusion: The burden of complete edentulism in China is projected to show an increasing trend from 2020 to 2022 and a decreasing trend from 2023 to 2030. Despite the decline in the burden of disease associated with complete edentulism in China, many problems remain to be solved.

Feasible CT features to distinguish incidental rib enhancement from sclerotic metastasis in patients with malignancies.

OBJECTIVE: To investigate the CT features of incidental rib enhancement (RE) and to summarize the CT characteristics for distinguishing the RE from sclerotic metastasis (SM) in patients with malignancies. MATERIAL AND METHODS: This retrospective observational study enrolled 79 patients with RE (involved 133 ribs) during October 2014 and December 2021. Another 53 patients with SM (160 SM) in the same period were selected randomly for comparison. The location, enhancement patterns of RE were reviewed. The CT values of RE regions and SM were measured and statistically analyzed. RESULTS: Most REs (70 patients, 88.6%) were in the 1st to 6th ribs. 50 patients had solitary RE and 29 with multiple REs in a regional distribution. All the REs were closely connected to the intercostal venous plexus (ICVP) ipsilateral to the injection site. No visible abnormalities on unenhanced scans were detected in all REs. One hundred and twenty REs (90.2%) had nodular/patchy enhancement. The CT value of RE regions in the venous phase was lower than that in the arterial phase (589.8 ± 344.2 HU versus 1188.5 ± 325.3 HU, p < 0.001). During the venous phase, most REs (125, 94.0%) shrank or disappeared. SM appeared similar on both contrast-enhanced and unenhanced scans in terms of shape and CT values. CONCLUSION: The RE demonstrated characteristic CT features. The manifestations of nodular/patchy enhancement in the arterial phase, decreased density and shrinkage or disappearance during the venous phase, and no abnormality on unenhanced scans, as well as a close connection with the ICVP, may help differentiate RE from SM.

Socioeconomic Inequalities in Oral Health among Adults in Guangxi, China.

PURPOSE: To examine the relationship between socioeconomic inequalities and oral health among adults in the Guangxi province of China. MATERIALS AND METHODS: The present work was designed as a cross-sectional study, and comprises a secondary analysis of the Fourth National Oral Health Survey from 2015-2016. A multistage cluster sampling method was adopted for this survey, conducted in three urban and three rural districts Guangxi province. Dental examinations were conducted to determine oral health indicators: decayed teeth (DT), clinical attachment loss (CAL) and missing teeth (MT). The outcome measures were DT, CAL and MT. A structured questionnaire was used to collect data on demographic characteristics and socioeconomic status (SES). Multiple logistic regression models were used to analyse the relationship between SES and oral health by adjusting covariates. RESULTS: The sample consisted of 651 participants aged 35-74 years. Logisitic analysis showed a statistically significant association between SES and oral health indicators. In the fully adjusted model, participants with primary education were more likely to suffer more DT (OR = 2.67, 95% CI: 1.17-6.10), teeth with CAL ≥ 4 mm (OR = 2.15, 95% CI: 1.25-3.67) and MT (OR = 3.04, 95% CI: 1.65-5.60) compared to the higher education group. Participants with secondary education exhibited a higher likelihood of experiencing increased MT compared to those in the higher education group in the fully adjusted model (OR = 3.21, 95% CI: 1.78-5.76). Household income was associated with DT and MT in the unadjusted model only. CONCLUSIONS: There was strong relationship between SES and oral health of adults. The survey suggested a relationship between low educational attainment and oral health.

N-carbamylglutamate supplementation induces functional egg production in layers by modulating liver transcriptome profiles.

Eggs rich in polyunsaturated fatty acids (PUFA), known as functional eggs, are animal products deemed beneficial to human health and possess high economic value. The production of functional eggs involves supplementing exogenous additives with the ability to regulate lipid metabolism. As N-Carbamylglutamate (NCG) serves as an endogenous arginine synthesizer, and arginine acts as the substrate for the formation of nitric oxide (NO), the biological function of NCG is partially mediated by NO. NO is a key regulatory molecule in lipid metabolism, suggesting that NCG may also have the ability to modulate lipid metabolism. In order to assess the capacity of NCG in regulating liver lipid metabolism and its potential application in producing functional eggs, we conducted a study to investigate the effects of dietary supplementation of NCG on production performance, serum, and liver NO levels, yolk fatty acid composition, and the liver transcriptome of layers. In this study, we utilized 30 layers of the Jinghong No.1 breed, all aged 45 wk. All the birds were randomly divided into 2 groups. Each group had 5 replicates, and each replicate had 3 birds. We provided them with different diets: one group received the basic diet, and the other group's diet was supplemented with 0.08% NCG. The experiment lasted for 14 wk. The results did not reveal any positive impact of NCG on production performance. However, NCG supplementation elevated NO levels in serum and liver, along with an increase in yolk PUFA, ω-3, and ω-6 fatty acids. Liver transcriptome analysis identified 124 upregulated differentially expressed genes (DEGs) and 43 downregulated DEGs due to NCG supplementation. Functional annotation using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database highlighted 3 upregulated DEGs (CPT1A, MOGAT1, and CHKA) and 2 downregulated DEGs (FASN and ETNPPL) associated with lipid metabolism. Pathway enrichment analysis revealed that CPT1A was enriched in the AMPK signaling pathway and the PPAR signaling pathway, while FASN was enriched in the AMPK signaling pathway. Thus, CPT1A and FASN are potential functional genes related to lipid metabolism facilitated by NCG supplementation. In summary, our study suggests that NCG supplementation modulates liver lipid metabolism, leading to the production of functional eggs in layers.

Common risk factors for dental caries and impaired glucose regulation in Guangxi, China.

OBJECTIVES: To assess the prevalence of caries and impaired glucose regulation (IGR) and try to investigate their common risk factors among adult residents in Guangxi province. METHODS: A cross-sectional study was conducted on a sample of 2993 adults from five different areas of Guangxi province. The sociodemographic data, history of personal habits such as diet and physical activities, physical measurements, oral examination results and biochemical laboratory test data were collected to establish a database and prepare a sound research model. Chi-square test and multiple logistic regression were used to analyse the risk factors for dental caries and IGR. RESULTS: The prevalence rate for caries was 85.9%, and the mean DMFT score was 7.35. In multiple logistic regression, after adjustment, education level, occupation, daily consumption of vegetables, weekly consumption of carbonated beverages and weekly exercise were associated with caries (odds ratio [OR]: 2.10, OR: 1.80, OR: 1.40, OR: 2.45, OR: 2.38). The prevalence of IGR was 33.5%, and after adjustment, results showed that occupation, body mass index, waist circumference, systolic blood pressure, diastolic blood pressure, high-density lipoprotein-C levels and low-density lipoprotein-C levels were significantly associated with IGR (OR: 0.80, OR: 1.70, OR: 1.56, OR: 1.88, OR: 1.60, OR: 1.43, OR: 1.48). The strength of association between caries/IGR and risk factors was a weak association or moderate association. CONCLUSIONS: We have not found common risk factors between dental caries and IGR. Therefore, further studies are needed to explore these common risk factors to prevent caries and IGR.

Shoot-to-root communication via GmUVR8-GmSTF3 photosignaling and flavonoid biosynthesis fine-tunes soybean nodulation under UV-B light.

Legume nodulation requires light perception by plant shoots and precise long-distance communication between shoot and root. Recent studies have revealed that TGACG-motif binding factors (GmSTFs) integrate light signals to promote root nodulation; however, the regulatory mechanisms underlying nodule formation in changing light conditions remain elusive. Here, we applied genetic engineering, metabolite measurement, and transcriptional analysis to study soybean (Glycine max) nodules. We clarify a fine-tuning mechanism in response to ultraviolet B (UV-B) irradiation and rhizobia infection, involving GmUVR8-dependent UV-B perception and GmSTF3/4-GmMYB12-GmCHS-mediated (iso)flavonoid biosynthesis for soybean nodule formation. GmUVR8 receptor-perceived UV-B signal triggered R2R3-MYB transcription factors GmMYB12-dependent flavonoid biosynthesis separately in shoot and root. In shoot, UV-B-triggered flavonoid biosynthesis relied on GmUVR8a, b, c receptor-dependent activation of GmMYB12L-GmCHS8 (chalcone synthase) module. In root, UV-B signaling distinctly promotes the accumulation of the isoflavones, daidzein, and its derivative coumestrol, via GmMYB12B2-GmCHS9 module, resulting in hypernodulation. The mobile transcription factors, GmSTF3/4, bind to cis-regulatory elements in the GmMYB12L, GmMYB12B2, and GmCHS9 promoters, to coordinate UV-B light perception in shoot and (iso)flavonoid biosynthesis in root. Our findings establish a novel shoot-to-root communication module involved in soybean nodulation and reveal an adaptive strategy employed by soybean roots in response to UV-B light.

Multiomics analysis reveals the genetic and metabolic characteristics associated with the low prevalence of dental caries.

Background: Despite poor oral hygiene, the Baiku Yao (BKY) ethnic group in China presents a low prevalence of dental caries, which may be related to genetic susceptibility. Due to strict intra-ethnic marriage rule, this ethnic has an advantage in studying the interaction between genetic factors and other regulatory factors related to dental caries. Methods: Peripheral blood from a caries-free adult male was used for whole genome sequencing, and the BKY assembled genome was compared to the Han Chinese genome. Oral saliva samples were collected from 51 subjects for metabolomic and metagenomic analysis. Multiomics data were integrated for combined analysis using bioinformatics approaches. Results: Comparative genomic analysis revealed the presence of structural variations in several genes associated with dental caries. Metabolomic and metagenomic sequencing demonstrated the caries-free group had significantly higher concentration of antimicrobials and higher abundance of core oral health-related microbiota. The functional analysis indicated that cationic antimicrobial peptide resistance and the lipopolysaccharide biosynthesis pathway were enriched in the caries-free group. Conclusions: Our study provided new insights into the specific regulatory mechanisms that contribute to the low prevalence of dental caries in the specific population and may provide new evidence for the genetic diagnosis and control of dental caries.

Improved figure of merit (z) at low temperatures for superior thermoelectric cooling in Mg3(Bi,Sb)2.

The low-temperature thermoelectric performance of Bi-rich n-type Mg3(Bi,Sb)2 was limited by the electron transport scattering at grain boundaries, while removing grain boundaries and bulk crystal growth of Mg-based Zintl phases are challenging due to the volatilities of elemental reactants and their severe corrosions to crucibles at elevated temperatures. Herein, for the first time, we reported a facile growth of coarse-grained Mg3Bi2-xSbx crystals with an average grain size of ~800 µm, leading to a high carrier mobility of 210 cm2 · V-1 · s-1 and a high z of 2.9 × 10-3 K-1 at 300 K. A [Formula: see text]T of 68 K at Th of 300 K, and a power generation efficiency of 5.8% below 450 K have been demonstrated for Mg3Bi1.5Sb0.5- and Mg3Bi1.25Sb0.75-based thermoelectric modules, respectively, which represent the cutting-edge advances in the near-room temperature thermoelectrics. In addition, the developed grain growth approach can be potentially extended to broad Zintl phases and other Mg-based alloys and compounds.

Association Between the SLC2A2 Gene rs1499821 Polymorphism and Caries Susceptibility.

Objectives: This study was designed to analyze the association between the SLC2A2 rs1499821 polymorphism and caries susceptibility in the Chinese Han, Zhuang, and Baikuyao populations. Materials and Methods: The present case-control study included 1067 12-year-old children: 481 with caries (142 Han, 166 Zhuang and 173 Baikuyao) and 586 who were caries-free (135 Han, 178 Zhuang and 273 Baikuyao). Questionnaires about diet and oral habits were obtained from all subjects. All of the children received dental examinations and DNA collection. The SLC2A2 rs1499821 SNP was genotyped using the SNPscan technique. Results: The rs1499821 T polymorphism was significantly associated with caries susceptibility in both the Han population and the combined populations of the three ethnic subgroups. SLC2A2 rs1499821 was associated with caries susceptibility in the dominant model in the Han (p = 0.045) population and the combined (p = 0.038) group. The CT+TT genotypes at rs1499821 were associated with a higher risk of caries in the Han (OR = 1.69, adjusted 95% CI: 1.01-2.81) and combined (OR = 1.33, adjusted 95% CI: 1.02-1.74) populations. In both Han (p = 0.009) and the combined populations (p = 0.004), there were statistically significant associations between the frequency of sweet food intake and dental caries. However, the rs1499821 polymorphisms did not associate with the frequency of sweet food intake in these ethnic subgroups. Conclusion: In the Han population, the SLC2A2 rs1499821 T allele and the frequency of sweet food intake may be regarded as risk factors for caries susceptibility. The SLC2A2 rs1499821 T allele had no association with the frequency of sweet food intake in any of the three ethnic groups.

Associations of PART1 and DEFB1 polymorphisms with Dental Caries in twelve-year-old children in Southern China: a cross-sectional study.

OBJECTIVE: The aim of this study was to assess associations of PART1 rs27565 and DEFB1 rs11362 polymorphisms with the prevalence of dental caries in twelve-year-old children in Nandan County, Guangxi, China. METHODS: A total of 1,061 children were included in this cross-sectional study and divided into two groups based on the Decayed, Missing and Filled teeth (DMFT) index: caries-free children (DMFT score = 0) and children with caries (DMFT score ≥ 1). Demographic characteristics, oral hygiene behaviour and dietary habits were collected through household records and questionnaires. Genomic DNA was extracted from buccal cells, and PART1 rs27565 and DEFB1 rs11362 polymorphisms were genotyped using a custom-designed 48-Plex single nucleotide polymorphism-scan kit. RESULTS: Carriers of the PART1 rs27565 C allele (odds ratio [OR] = 1.338, 95% confidence interval (CI) = 1.015-1.764, P value = 0.039) and carriers of the DEFB1 rs11362 T allele (OR = 1.364, 95% CI = 1.056-1.762, P value = 0.017) had a higher risk of caries. Carriers of the PART1 rs27565 TC or CC genotype who ate sugary food more than once a week had a 1.6-fold higher risk of caries than TT carriers who ate sugary food at most once a week (OR = 1.579, 95% CI = 1.032-2.414, P value = 0.035). Carriers of the DEFB1 rs11362 CT or TT genotype who ate sugary food more than once a week had a 2.1-fold higher risk of caries than CC carriers who ate sugary food at most once a week (OR = 2.057, 95% CI = 1.438-2.940, P value < 0.001). CONCLUSION: PART1 rs27565 and DEFB1 rs11362 polymorphisms were associated with caries in 12-year-old children in Nandan County, Guangxi, China. Carriers of the PART1 rs27565 TC or CC genotype and the DEFB1 rs11362 CT or TT genotype who ate sugary food more than once a week had a high probability of having caries.

Highly efficient thermoelectric air conditioner with kilowatt capacity realized by ground source heat-exchanging system.

The enormous need for refrigeration of modern human life has inevitably aggravated the environmental crisis worldwide. To date, there are very few refrigeration technologies available beholding both harmless refrigerants and high efficiency. Here, we proposed a geothermal-thermoelectric air conditioning system (GeoTEAC) with refrigerant-free and high energy efficiency through synergistically combining the merits of thermoelectric effect and ground source heat exchanging system. The system showed competitive cooling and heating COPs of 5.83 and 2.92, respectively, with kilowatt capacity, which are 3-4 times higher than that of previously reported thermoelectric air-conditioning setups. For a conceptual scenario, we demonstrated the lowest TEWI values for the GeoTEAC system among different air-conditioning types. Our work provides sustainable and climate-friendly solutions to realize worldwide emission peaks and carbon neutralization.

Improving glutathione production by engineered Pichia pastoris: strain construction and optimal precursor feeding.

Glutathione (GSH) is a metabolite that plays an important role in the fields of pharmacy, food, and cosmetics. Thus, it is necessary to increase its production to meet the demands. In this study, ScGSH1, ScGSH2, and StGshF were heterologously expressed in Pichia pastoris GS115 to realize the dual-path synthesis of GSH in yeast. To explore the effects of ATP metabolism on the synthesis of GSH, enzymes (ScADK1, PpADK1, VsVHB) of the ATP-related metabolic pathway and the energy co-substrate sodium citrate were taken into account. We found that both ScADK1 and sodium citrate had a positive influence on the synthesis of GSH. Then, a fermentation experiment in Erlenmeyer flasks was performed using the G3-SF strain (containing ScGSH1, ScGSH2, StGshF, and ScADK1), with the highest GSH titer and yield of 999.33 ± 47.26 mg/L and 91.53 ± 4.70 mg/g, respectively. Finally, the fermentation was scaled up in a 5-L fermentor, and the highest titer and yield were improved to 5680 mg/L and 45.13 mg/g, respectively, by optimizing the addition conditions of amino acids (40 mM added after 40 h). Our work provides an alternative strategy by combining dual-path synthesis with energy metabolism regulation and precursor feeding to improve GSH production. Key Points • ScGSH1, ScGSH2, and StGshF were overexpressed to achieve dual-path synthesis of GSH in yeast. • ScADK1 was overexpressed, and sodium citrate was added to increase the energy supply for GSH synthesis. • The addition conditions of amino acids were optimized to realize the efficient synthesis of GSH.

Cost-effectiveness analysis of the oral health promotion model in rural primary schools in Guangxi Zhuang Autonomous Region / 口腔疾病防治

Objective@#To evaluate the caries preventive effect and economic outcome of an oral health promotion model in rural primary schools in Guangxi Zhuang Autonomous Region.@*Methods@# In November 2015, a baseline survey was conducted on the caries prevalence of rural first graders in program areas, and then a program intervention was carried out on the first graders of target primary schools. The intervention methods included the distribution of oral health care products, oral health education, teacher training, etc. In 2020, the method of cluster random sampling was adopted to include the sixth graders who received the program intervention as first graders and were still available in 2020 as the intervention group. During this period, the sixth graders transferred from foreign schools who failed to receive the program intervention as first graders were included in the non-intervention group. The caries preventive effect was evaluated by analyzing the caries epidemiological data of 2 652 children aged 11-13 years, comparing the intervention and non-intervention group. The cost of the program was estimated by the structural analysis method. A decision tree model was established by TreeAge pro2019 and incorporated into the effect parameters and cost parameters for cost-effectiveness analysis and sensitivity analysis.@* Results @# The prevalence of caries in the intervention group was 54.8%, and the mean DMFT was 1.36 ± 1.64, both of which were lower than those in the non-intervention group. The difference in prevalence and mean DMFT between the two groups was statistically significant (P < 0.05). It costs CNY 319.83 per child to reduce suffering from caries. The number of patients with caries in the intervention group was the most sensitive indicator of an economic effect. The probability of a cost-effectiveness advantage for the program was 92.2%. @*Conclusion @# This oral health promotion model used in rural schools demonstrated a caries preventive effect that was very likely economically advantageous. It is of practical significance to improve and promote this model in the Guangxi Zhuang Autonomous Region.

Association between socioeconomic status and dental caries among Chinese preschool children: a cross-sectional national study.

OBJECTIVES: Socioeconomic inequalities in oral health are often neglected in oral health promotion. This cross-sectional study assessed the association between dental caries and socioeconomic status (SES) among preschool children in China. DESIGN: Cross-sectional study. SETTING: Data from the Fourth National Oral Health Survey of China (2015), comprising of 40 360 children aged 3-5 years was used. METHODS: Dental caries indicators including prevalence of dental caries, dental pain experience and number of decayed, missing and filling teeth (dmft). SES indicators included parental education and household income. The associations between SES and dental caries were analysed by using negative binomial regression or Poisson regression models according to data distribution. Relative and absolute inequalities in dental caries were quantified by using the Relative Index of Inequality (RII) and Slope Index of Inequality (SII), respectively. RESULTS: There were significant associations between SES and prevalence of dental caries and dmft (p<0.001). Children from lower educated (RII 1.36, 95% CI 1.3 to 1.43; SII 0.97, 95% CI 0.81 to 1.13) and lower household income (RII 1.17, 95% CI 1.11 to 1.24; SII 0.55, 95% CI 0.35 to 0.75) families had higher dmft than those from well-educated and most affluent families. Relative and absolute inequalities in dental caries were larger in urban areas by household income, and in rural areas by parental education. CONCLUSIONS: Association between dental caries and SES was demonstrated and socioeconomic inequalities in dental caries existed among Chinese preschool children.

Laser therapy versus topical desensitising agents in the management of dentine hypersensitivity: A meta-analysis.

OBJECTIVES: To compare the effectiveness of lasers and topical desensitising agent treatments for dentine hypersensitivity. METHODS: PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE and ISI Web of Knowledge were electronically searched without restrictions. Study search, selection, data extraction and assessment of risk of bias were conducted independently by two reviewer authors. All analyses were performed using Review Manager 5.3 (Cochrane Collaboration). RESULTS: This meta-analysis included 13 eligible studies that compared topical desensitising agents and Nd:YAG or diode laser. Four, six and three studies were considered to have low, moderate and high risks of bias, respectively. The follow-up period varied from immediate to 9 months. All comparisons except the 3-month Nd:YAG laser parallel group and 6-month diode laser group showed that the clinical efficacy of lasers for dentine hypersensitivity was not significantly different with topical desensitising agents. CONCLUSION: We found low-quality evidence that was insufficient to draw any conclusions regarding the superiority of lasers or conventional topical desensitising agents in the treatment of DH. Further well-designed RCTs on this topic are needed to draw definitive conclusions.

Effectiveness of fluoride varnish on caries in the first molars of primary schoolchildren: a 3-year longitudinal study in Guangxi Province, China.

AIMS: To evaluate the effectiveness of 5% sodium fluoride varnish on caries in first permanent molars and to assess the suitability of using this method to control caries among children in rural areas of Guangxi province, China. METHODS: A total of nine schools with 32 classes were selected by simple random sampling. There were 999 students in the experimental group and 1,004 in the control group. The experimental group received oral health education and topical application of 5% sodium fluoride varnish, while the control group received oral health education only. Dental examinations were performed in November 2014 and November 2017, and the modified International Caries Detection and Assessment System (ICDAS-II) was used to record the caries status of the first permanent molars. The data were entered into SPSS 22 for statistical analysis. RESULTS: A total of 1,748 students (853 in the experimental group and 895 in the control group) completed the study. After 3 years of intervention, the experimental group had a lower prevalence of caries, a lower caries increment, a lower decayed, missing and filled teeth (DMFT) index and a lower decayed, missing and filled surfaces (DMFS) index compared with the control group (respectively: 58.9% vs 65.5%, 34.8% vs 42.1%, 1.38 vs 1.59 and 2.06 vs 2.38). All the differences were statistically significant (P < 0.05). CONCLUSION: In this study population, twice-yearly application of 5% sodium fluoride varnish and oral health education were more effective for preventing caries in first permanent molars than oral health education alone. The implementation of fluoride varnish application as a public health measure in schools in rural areas is recommended.

Spark Plasma Sintered Bulk Nanocomposites of Bi2Te2.7Se0.3 Nanoplates Incorporated Ni Nanoparticles with Enhanced Thermoelectric Performance.

Bi2Te3-based compounds are important near room temperature thermoelectric materials with commercial applications in thermoelectric modules. However, new routes leading to improved thermoelectric performance are highly desirable. Incorporation of superparamagnetic nanoparticles was recently proposed as a means to promote the thermoelectric properties of materials, but its feasibility has rarely been examined in mainstream thermoelectric materials. In this study, high quality single-crystalline Bi2Te2.7Se0.3 nanoplates and Ni nanoparticles were successfully synthesized by solvothermal and thermal decomposition methods, respectively. Bulk nanocomposites consisting of Bi2Te2.7Se0.3 nanoplates and superparamagnetic Ni nanoparticles were prepared by spark plasma sintering. It was found that incorporation of Ni nanoparticles simultaneously increased the carrier concentration and provided additional scattering centers, which resulted in enlarged electric conductivities and Seebeck coefficients. The greatly improved ZT was achieved due to the increase in power factor. Spark plasma sintered bulk nanocomposites of Bi2Te2.7Se0.3 nanoplates incorporated by 0.4 mol %Ni nanoparticles (in molar ratio) showed a figure-of-merit ZT of 0.66 at 425 K, equivalent to 43% increase when compared to pure Bi2Te2.7Se0.3 nanoplates. The results revealed that incorporation of magnetic nanoparticles could be an effective approach for promoting the thermoelectric performance of conventional semiconductors.

Dual-entropy-driven catalytic amplification reaction for ultra-sensitive and visible detection of Hg2+ in water based on thymine-Hg2+-thymine coordination chemistry.

An ultra-sensitive and visible Hg2+ detection strategy was established. It was based on T-Hg2+-T coordination chemistry and a dual-entropy-driven catalytic reaction (EDCR). The dual EDCR was initiated by T-Hg2+-T coordination chemistry, resulting in the release of a G-rich sequence to form a hemin/G-quadruplex-HRP-mimicking DNAzyme, and then catalyzing 3,3',5,5'-tetramethylbenzidine (TMB) into TMB+, with a color change from colorless to blue. This method showed great sensitivity and excellent selectivity, and the limit of detection reached 0.6 pM. The feasibility of this method was demonstrated by real water samples. Moreover, the visible color change provided the possibility of ultra-sensitive detection of Hg2+ by the naked eye.