Digitally driven tooth reduction guide combined with chairside tooth preparation monitoring tool for veneer preparation: A dental technique.

This article describes a completely digital workflow for ceramic veneer preparation with computer-aided design and computer-aided manufacturing technology. A simplified 3-dimensionally printed tooth reduction guide for accurate intraoral trial restorations is manufactured to indicate the range of the unprepared tooth surfaces erupted beyond the digital esthetic waxing. By using the Medit Design software program, chairside tooth preparation is monitored by accurate measurement of the amount of tooth reduction relative to the required restorative contours. Compared with conventional techniques, this technique improves the control and efficiency of tooth preparation, aiding in enamel preservation and achieving a predictable prosthetic effect.

Copper-Catalyzed Synthesis of 4-CF3-1,2,3-Triazoles: An Efficient and Facile Approach via Click Reaction.

Incorporation of a trifluoromethyl group with 1,2,3-triazoles motifs was described. We explored a click reaction approach for regioselective synthesis of 1-susbstituted-4-trifluoromethyl-1,2,3-triazoles in which 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) reacts with commercial 2-bromo-3,3,3-trifluoropropene (BTP) to form 3,3,3-trifloropropyne (TFP) in situ. Arising from merits associated with the availability and stability of BTP, and the high efficiencies of CuI/1,10-Phenanthroline (Phen)-catalyzed cycloaddition reactions of azides with alkynes, this readily performed click process takes place to form the target 1,2,3-triazoles in high yields, and with a wide azide substrate scope. The potential value of this protocol was demonstrated by its application to a gram-scale reaction.

Maxillary midline diastema closure with sectional feldspathic porcelain veneers: A case series followed 1 to 4 years.

OBJECTIVE: To evaluate clinical outcome of maxillary midline diastema closure using sectional feldspathic porcelain veneers up to 4 years. MATERIALS AND METHODS: Five female patients with stable maxillary midline diastema were included in the current study and restored with minimal invasive sectional feldspathic porcelain veneers under dental microscope. Esthetic, functional, as well as biologic properties of sectional veneers were evaluated according to the World Dental Federation (FDI) criteria after 1 to 4 years' follow-up. RESULTS: Based on FDI criteria, all five cases were evaluated as clinically excellent to satisfactory during a mean observation period of 26.4 months. Slight to moderate cervical marginal staining was observed in two cases after 3 to 4 years' follow-up. Slight white line or ditching of labial surface margin was found in most cases, but it is not easy to be noticed with saliva covering the margins. CONCLUSIONS: Sectional feldspathic porcelain veneers presented satisfying clinical outcome with potential long-term esthetic risk for maxillary midline diastema closure. CLINICAL SIGNIFICANCE: 1. Sectional feldspathic porcelain veneers presented satisfying short to medium term clinical performance when applied to close maxillary midline diastema. 2. The exposure of labial surface margin may increase a long-term potential esthetic risk.

Integrative Analysis of the Transcriptome and Metabolome Reveals the Developmental Mechanisms and Metabolite Biosynthesis of the Tuberous Roots of Tetrastigma hemsleyanum.

The tuberous root of Tetrastigma hemsleyanum Diels et Gilg (T. hemsleyanum) is a traditional Chinese medicine with a wide range of clinical applications. However, the scarcity of its wild resources, its low yield, and the variable quality that results from its artificial cultivation leads to expensive market prices that are not conducive to the further industrial development of T. hemsleyanum. In this study, transcriptomic and non-targeted metabolomic analyses were integrated to explore the underlying molecular mechanisms and metabolite biosynthesis that occur during its root development. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed that differentially expressed genes (DEGs) were predominantly enriched for processes associated with flavonoid and phenylpropanoid biosynthesis, starch and sucrose metabolism, and plant hormone signal transduction. Genes related to lignin were downregulated in tuberous roots (TRs), resulting in a decrease in lignification and the downregulation of metabolites related to flavonoids and phenylpropanoid biosynthesis. In addition, the expression levels of starch- and sucrose-related genes were upregulated in TRs. The root development of SYQ is also related to IAA, GA, ABA, and JA signaling pathways. Collectively, this study lays the foundation for analyzing the root development and quality-modulating mechanisms employed by T. hemsleyanum; this will be beneficial in conducting molecular-assisted breeding and controlling its secondary metabolite production.

The mechanism of semiconductor to metal transition in the hydrogenation of VO2: a density functional theory study.

VO2 is a glamorous material with specific metal-semiconductor-transition (MST). The hydrogenation of VO2 could make it a promising material for application in an ambient environment. In this work, we reveal the hydrogenation of VO2 by modulating the hydrogen content and monitoring interaction models, adsorption energies, the density of states, electron density, and charge transfer between hydrogen and the VO2 surface. The monoclinic VO2(020) surface shows a distinct electronic polarization, and the majority spin band gap is larger than the minority spin band gap. The energy gap of the monoclinic VO2 surface is highly dependent on the majority spin band. The interaction between hydrogen and oxygen in the first layer of the VO2 surface is stronger than those in other layers. The energy gap on the surface of VO2 decreases gradually with increasing hydrogen content, and when twelve hydrogen atoms are adsorbed on the surface, an energy gap of 0 eV eventually appears, suggesting that monoclinic VO2 turns into a metallic conductor from a semiconductor. In the process of VO2 hydrogenation, the electron transfer only occurs between hydrogen and its connected oxygen atoms on the VO2 surface, and vanadium atoms just play an intermediary role.

H3K27ac-induced FOXC2-AS1 accelerates tongue squamous cell carcinoma by upregulating E2F3.

BACKGROUND: The important roles of lncRNAs have been reported in cancers, including tongue squamous cell carcinoma (TSCC). Here, we investigated the functional role and molecular mechanisms of lncRNA FOXC2-AS1 in TSCC. METHODS: The expression level of FOXC2-AS1 in TSCC was determined by RT-qPCR. Its biological role was evaluated through colony formation assay, flow cytometry, wound healing, transwell, and Western blot analyses. The interactions among gene were tested by mechanistic investigations. RESULTS: FOXC2-AS1 expression was high in TSCC tissues and cells. Functional assays in vitro showed that silencing FOXC2-AS1 restrained cell proliferation, cell cycle, migration, invasion, and EMT. In the mechanism, it was verified that H3K27 acetylation (H3K27ac) triggered an increase in FOXC2-AS1 expression. Furthermore, FOXC2-AS1 was identified as a cytoplasmic lncRNA and served as a ceRNA to upregulate E2F3 expression via sponging miR-6868-5p. CONCLUSION: H3K27ac-induced FOXC2-AS1 exhibits carcinogenic property in TSCC by the miR-6868-5p/E2F3 axis.

Two-Dimensional ZnS/SnS2 Heterojunction as a Direct Z-Scheme Photocatalyst for Overall Water Splitting: A DFT Study.

Direct Z-scheme photocatalysts have attracted extensive attention due to their strong redox ability and efficient separation of photogenerated electron-hole pairs. In this study, we constructed two types of ZnS/SnS2 heterojunctions with different stacking models of ZnS and SnS2 layers, and investigated their structures, stabilities, and electronic and optical properties. Both types of heterojunctions are stable and are direct Z-scheme photocatalysts with band gaps of 1.87 eV and 1.79 eV, respectively. Furthermore, their oxidation and reduction potentials straddle the redox potentials of water, which makes them suitable as photocatalysts for water splitting. The built-in electric field at the heterojunction interface improves the separation of photogenerated electron-hole pairs, thus enhancing their photocatalytic efficiency. In addition, ZnS/SnS2 heterojunctions have higher carrier mobilities and light absorption intensities than ZnS and SnS2 monolayers. Therefore, the ZnS/SnS2 heterojunction has a broad application prospect as a direct Z-scheme visible-light-driven photocatalyst for overall water splitting.

DFT study on the electronic structure and optical properties of an Au-deposited α-Fe2O3 (001) surface.

The electronic structure and optical properties of gold clusters deposited on an α-Fe2O3 surface were studied by using density functional theory (DFT), with a special emphasis on the influence of Au cluster sizes. There is a strong interaction between Au clusters and the α-Fe2O3 surface, and the binding energy increases with an increase of Au cluster size. The Au atoms of the gold cluster are bonded to the iron atoms of the α-Fe2O3 surface for the Au/α-Fe2O3 system, and the electrons transfer from the Au cluster to the α-Fe2O3 surface with the largest number of electrons transferred for 4Au/α-Fe2O3. The peaks of the refractive index, extinction coefficient and dielectric function induced by Au clusters appear in the visible range, which results in the enhanced optical absorption for the Au/α-Fe2O3 system. The optical absorption intensifies with increasing Au cluster size in the visible range, showing a maximum value for 4Au/α-Fe2O3. Further increasing the Au cluster size above 4Au results in a decrease in absorption intensity. The results are in good agreement with those of the refractive index, extinction coefficient and dielectric function.

Methodology improvement of bulk compressive creep test: Deformation measurement and loading rate.

OBJECTIVES: (1) To identify improvements when bulk compressive creep testing of dental resin composite materials to reduce the sensitivity to the surface morphology and parallelism of specimens, to generate more accurate strain (displacement) measurement values. (2) To investigate the effect of loading rate on the creep and recovery behavior under bulk compressive creep test. METHODS: Cylindrical composite resin specimens were subjected to bulk compressive creep test with conventional and modified methodology (with/without introduction of stainless steel hemisphere and preload process). Furthermore, specimens undertook different loading rates ranging from 1 N/s to 50 N/s. Maximum deformation, creep deformation, permanent set as well as percentage of recovery during the creep and recovery procedure were compared, and surface topography changes before and after preload process was evaluated by laser scanning confocal. Burgers model was used to investigate the effect of improvements to each part of viscoelastic deformation of resin specimens. RESULTS: (1) The influence of surface evenness of resin specimens could be reduced by addition of preload process before the bulk compressive creep test resulting in significantly decreased permanent set (p = 0.002), and increased recovery to 91.7 % (p < 0.001). While the standard deviation of maximum deformation, permanent set and percentage of recovery had the smallest values when hemisphere was introduced to loading chain. (2) With increasing loading rate of bulk compressive creep tests, creep deformation increased and this trend became statistically significant when the loading rate reached 50 N/s. SIGNIFICANCE: The accuracy of deformation measurement during bulk compressive creep test could be improved by means of introducing stainless steel hemisphere to the loading chain, and adding preload process to loading protocol.

Identification of New Proteins and Potential Mitochondrial F1F0-ATPase Inhibitor Factor 1-Associated Mechanisms in Arabidopsis thaliana Using iTRAQ-Based Quantitative Proteomic Analysis.

The mitochondrial synthesis of ATP makes a vital contribution to the growth and development of biological organisms, in which the enzyme mitochondrial F1F0-ATP synthase plays a pivotal role, in that it can either synthesize or hydrolyze cellular ATP. The finding of our previous study revealed that mitochondrial F1F0-ATPase inhibitor factor 1 (IF1) in Arabidopsis thaliana has a conserved function as an endogenous inhibitor affecting cellular energy status and plays an important role in plant growth and reproduction, particularly in fertility. In this study, to gain an insight into IF1-related traits, we performed isobaric tags for relative and absolute quantitation labeling analysis. In total, 67 of 4778 identified proteins were identified as differentially expressed proteins (DEPs; 59 up-regulated and 8 down-regulated) between wild-type and if1 mutant Arabidopsis thaliana seedlings. Gene ontology enrichment analysis revealed that these DEPs were the most significantly enriched in pathways such as "long-day photoperiodism, flowering," "positive regulation of protein import into chloroplast stroma," and "pollen sperm cell differentiation," which are closely associated with reproductive development. Moreover, Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed that photosynthesis was the pathway most significantly enriched with DEPs. Collectively, our results revealed a global shift in protein abundance patterns corresponding to AtIF1 mutation, entailing changes in the abundance of multiple key proteins and metabolic processes, which will provide a valuable proteomic foundation for future studies.

Identification and characterization of a natural SNP variant in ALTERNATIVE OXIDASE gene associated with cold stress tolerance in watermelon.

Alternative oxidase (AOX) is a mitochondrial enzyme encoded by a small nuclear gene family, which contains the two subfamilies, AOX1 and AOX2. In the present study on watermelon (Citrullus lanatus), only one ClAOX gene, belonging to AOX2 subfamily but having a similar gene structure to AtAOX1a, was found in the watermelon genome. The expression analysis suggested that ClAOX had the constitutive expression feature of AOX2 subfamily, but was cold inducible, which is normally considered an AOX1 subfamily feature. Moreover, one single nucleotide polymorphism (SNP) in ClAOX sequence, which led to the change from Lys (N) to Asn (K) in the 96th amino acids, was found among watermelon subspecies. Ectopic expression of two ClAOX alleles in the Arabidopsis aox1a knock-out mutant indicated that ClAOXK-expressing plants had stronger cold tolerance than aox1a mutant and ClAOXN-expressing plants. Our findings suggested watermelon genome contained a single ClAOX that possessed the expression features of both AOX1 and AOX2 subfamilies. A naturally existing SNP in ClAOX differentiated the cold tolerance of transgenic Arabidopsis plants, impling a possibility this gene might be a functional marker for stress-tolerance breeding.

Identification and characterization of Arabidopsis thaliana mitochondrial F1F0-ATPase inhibitor factor 1.

Mitochondrial F1F0-ATP synthase (F1F0-ATPase) inhibitor factor 1 (IF1) has been extensively characterized as an endogenous inhibitor that prevents the hydrolysis of adenosine-5'-triphosphate (ATP) by mitochondrial ATPases in mammals and yeasts; however, IF1's functions in plants remain unclear. Here, a comprehensive bioinformatic analysis was performed to identify plant mitochondrial F1F0-ATPase IF1 orthologs. Plant IF1s contain a conserved F1F0-ATPase inhibitory domain, but lack the antiparallel α-helical coiled-coil structure compared with mammalian IF1s. A subcellular localization analysis in Arabidopsis thaliana revealed that AtIF1-green fluorescent protein was present only in mitochondria. Additionally, AtIF1 was widely expressed in diverse organs and intense ß-glucuronidase staining was observed in reproductive tissues and germinating seeds. Compared with the wild-type and p35S:AtIF1-if1 etiolated seedlings, the ATP/ADP ratio was significantly lower in the AtIF1 T-DNA knockout seedlings (if1 mutant) growing under dark conditions, suggesting that AtIF1 can influence the energy state of cells. A significant reduction in seed yield and strong growth retardation under dark conditions were observed in the if1 mutant line. Furthermore, if1 plants exhibited a substantially decreased sensitivity to abscisic acid. Thus, the A. thaliana mitochondrial IF1, which is a conserved F1F0-ATPase inhibitor, is crucial for plant growth and responses to abscisic acid.

A Casparian strip domain-like gene, CASPL, negatively alters growth and cold tolerance.

A cold-induced transcript encoding a Casparian strip membrane domain (CASP)-like protein (ClCASPL) was identified in watermelon (Citrullus lanatus). Fluorescence microscopy analysis showed that ClCASPL-GFP is localized in the plasma membrane. The orthologous gene in Arabidopsis thaliana (AtCASPL4C1) was also found to play an important role in cold tolerance. Expression analysis using a ß-glucuronidase (GUS) reporter reveals that AtCASPL4C1 is widely expressed in a variety of organs and is cold inducible. Analysis of AtCASPL4C1 T-DNA knock-out plants showed altered growth dynamics, faster growth, increased biomass (dry weight) and earlier flowering compared to wild type (Col-0) and ClCASPL overexpressing plants. AtCASPL4C1 knock-out plants showed elevated tolerance to cold stress, while overexpressing CICASPL resulted in increased sensitivity to cold stress in Arabidopsis. Interestingly, AtCASPL4C1 knock-out plants did not display significant alterations in the Casparian strip formation in roots. Thus, the combination of these results suggests a role for CICASPL and AtCASPL4C1 beyond Casparian strip formation in roots, possibly indicating a more fundamental role in vascular tissue.