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Purpose: To evaluate the physical and mechanical properties of zirconia ceramic manufactured with stereolithography and to quantitatively analyze the internal and marginal adaptation of the zirconia ceramic dental crowns.Materials and Methods: A resin-based zirconia suspension with a solid content of 45 vol% was prepared. Zirconia dental crowns (n = 5) for the maxillary right first molar were designed and manufactured. Physical and mechanical properties-including density, sintering shrinkage, flexural strength, Weibull parameters, phase composition, and microstructure-of the stereolithography-manufactured zirconia crowns were evaluated. A three-dimensional subtractive analysis technique was used to evaluate the internal and marginal adaptation.Results: The stereolithography-manufactured zirconia (n = 22) achieved a flexural strength of 812 ± 128 MPa and a Weibull modulus of 7.44. Quantitative analysis of the fabricated zirconia crowns showed a cement space of 63.40 ± 6.54 μm in the occlusal area, 135.08 ± 10.55 μm in the axial area, and 169.58 ± 18.13 μm in the marginal area.Conclusion: Within the limits of this study, the strength of the stereolithography-manufactured zirconia was adequate for fabricating dental crowns. However, internal and marginal adaptation are not yet ideal for clinical application. [ABSTRACT FROM AUTHOR]

The association between tooth movement and remodelling of surrounding bone is controversial. To analyse the effect of tooth movement on alveolar bone changes in maxillary and mandibular anterior teeth by cone‐beam computed tomography (CBCT). The Embase, Cochrane Library and Medline databases were searched without any language restrictions. Longitudinal studies using CBCT to observe alveolar bone changes of maxillary and mandibular anterior teeth during orthodontic treatment were included. Two independent reviewers performed the study selection, data extraction and methodological quality assessment. A total of 26 studies were included in this review, 14 of which were eligible for quantitative synthesis. In extraction cases, meta‐analysis showed vertical bone loss on the labial (0.36 mm) and lingual (0.94 mm) sides of maxillary incisors, and lingual bone thickness decreased significantly at the cervical level (0.57 mm). In non‐extraction cases, vertical alveolar bone loss was significant on the labial side (0.97 mm) and lingual side (0.86 mm) of mandibular incisors. Subgroup analysis for skeletal class III patients indicated that vertical alveolar bone loss was 1.16 mm on the labial side and 0.83 mm on the lingual side of mandibular incisors. The absence of high‐quality studies and the high heterogeneity of the included studies were limitations of this systematic review and meta‐analysis. Based on limited evidence, alveolar bone height and thickness, especially at the cervical level, decreased during both labial and lingual movement of anterior teeth. [ABSTRACT FROM AUTHOR]

This paper investigates a novel micro-channel flat separated loop heat pipe system for cooling the information technology equipment in the data centres through theoretical and experimental analysis and by assessing the impact of the inlet water temperature on system performance. A computer model is developed to simulate the steady-state performance of the micro-channel flat separated loop heat pipe system. After comparing the experimental and modelling results, the new and conventional system under the same working conditions, the model is validated yielding high accuracy in predicting the performance of the micro-channel flat separated loop heat pipe system with recorded error being limited to 2.16–8.97%. The new system has better performance than the conventional system. Under the operating conditions of heat load intensity of 1,000 W/m2, water flow rate of 0.28 m3/h, refrigerant filling rate of 30%, ambient air temperature of 26°C, and evaporator and condenser height difference of 0.8 m, the performance of the system has been explored at inlet temperature from 15 to 24°C with increments of 3°C. The system's averaged heat transfer efficiency was found to decrease with the increase in inlet temperature. This research provides valuable insight into the data centre information technology equipment cooling, which is of great significance for energy saving and environmentally friendly operation of data centres. [ABSTRACT FROM AUTHOR]

Little has been established on the relationship between the mevalonate (MVA) pathway and other metabolic pathways except for the sterol and glucosinolate biosynthesis pathways. In the MVA pathway, 3-hydroxy-3-methylglutaryl-CoA synthase (HMGS) catalyzes the condensation of acetoacetyl-CoA and acetyl-CoA to form 3-hydroxy-3-methylglutaryl-coenzyme A. Our previous studies had shown that, while the recombinant Brassica juncea HMGS1 (BjHMGS1) mutant S359A displayed 10-fold higher enzyme activity than wild-type (wt) BjHMGS1, transgenic tobacco overexpressing S359A (OE-S359A) exhibited higher sterol content, growth rate and seed yield than OE-wtBjHMGS1. Herein, untargeted proteomics and targeted metabolomics were employed to understand the phenotypic effects of HMGS overexpression in tobacco by examining which other metabolic pathways were affected. Sequential window acquisition of all theoretical mass spectra quantitative proteomics analysis on OE-wtBjHMGS1 and OE-S359A identified the misregulation of proteins in primary metabolism and cell wall modification, while some proteins related to photosynthesis and the tricarboxylic acid cycle were upregulated in OE-S359A. Metabolomic analysis indicated corresponding changes in carbohydrate, amino acid and fatty acid contents in HMGS-OEs, and F-244, a specific inhibitor of HMGS, was applied successfully on tobacco to confirm these observations. Finally, the crystal structure of acetyl-CoA-liganded S359A revealed that improved activity of S359A likely resulted from a loss in hydrogen bonding between Ser359 and acyl-CoA, which is evident in wtBjHMGS1. This work suggests that regulation of plant growth by HMGS can influence the central metabolic pathways. Furthermore, this study demonstrates that the application of the HMGS-specific inhibitor (F-244) in tobacco represents an effective approach for studying the HMGS/MVA pathway. [ABSTRACT FROM AUTHOR]