Aim
To test the ability of periapical radiography (PA) and cone‐beam computed tomography (CBCT) to determine the presence/absence of periapical lesions and examine the reliability of volumetric ...measurements of periapical lesions on CBCT scans.
Methodology
After tooth extractions in human mandibles, bone defects were cut at the base of extraction sockets to mimic periapical bone lesions. The teeth were then returned into the extraction sockets. Sixty‐three roots of anterior teeth, premolars and molars with artificial periapical lesions and 37 roots without lesions were examined with PA and CBCT. Presence/absence of periapical lesion was noted. The CBCT‐based volume of each lesion (Vct) was measured using Amira software 5.4 (Visage Imaging GmbH, Berlin, Germany). A replica of each lesion was created using silicone impression material, and the volume of the replica was measured using a water displacement method, representing the physical volume of the lesion (Vp). Regression analysis was used to test the correlation between the Vp and Vct values.
Results
The positive and negative predictive values and accuracy for CBCT in diagnosing periapical lesions were all 1, compared with 1, 0.64 and 0.79 for PA diagnosis. Twenty‐one (33%) lesions were undetected by PA. The Vp (21.5 ± 11.0 mm3) and Vct (21.4 ± 11.5 mm3) values of 63 lesions were highly correlated (R2 = 96.9%, P < 0.001).
Conclusion
Cone‐beam computed tomography is more accurate than PA in diagnosing periapical lesions associated with mandibular teeth. The volumes of artificial mandibular periapical lesions were accurately measured with CBCT data.
The fatigue crack growth behavior in 20CrMnTi lath martensitic steel with a hierarchical structure was investigated at room temperature. The microstructure was quantitatively characterized by optical ...microscopy, scanning electron microscopy, electron backscattering diffraction, and transmission electron microscopy. Crack growth tests were performed at a stress ratio of 0.1 under the control of a stress intensity factor range using compact tension specimens. The results show that the lath martensite with medium grain size quenched in ice salt water possessed the highest fatigue crack propagation resistance, which was attributed to the relatively high intrinsic propagation resistance and extrinsic propagation resistance. Meanwhile, the results indicate that the intrinsic propagation resistance increased with the grain size, while the extrinsic propagation resistance showed an inverse tendency. In addition, the effect of substructure on the fatigue propagation properties is discussed. The deflection angle of block interfaces in the crack growth path indicated the block unit had a significant effect on the fatigue crack propagation behavior of lath martensitic steel. Based on the Taylor model, the block size (db) was considered to be the effective grain size for controlling the crack growth threshold value (∆Kth).
Among numerous active electrode materials, nickel hydroxide is a promising electrode in electrochemical capacitors. Nickel hydroxide research has thus far focused on the crystalline rather than the ...amorphous phase, despite the impressive electrochemical properties of the latter, which includes an improved electrochemical efficiency due to disorder. Here we demonstrate high-performance electrochemical supercapacitors prepared from amorphous nickel hydroxide nanospheres synthesized via simple, green electrochemistry. The amorphous nickel hydroxide electrode exhibits high capacitance (2,188 F g(-1)), and the asymmetric pseudocapacitors of the amorphous nickel hydroxide exhibit high capacitance (153 F g(-1)), high energy density (35.7 W h kg(-1) at a power density of 490 W kg(-1)) and super-long cycle life (97% and 81% charge retentions after 5,000 and 10,000 cycles, respectively). The integrated electrochemical performance of the amorphous nickel hydroxide is commensurate with crystalline materials in supercapacitors. These findings promote the application of amorphous nanostructures as advanced electrochemical pseudocapacitor materials.
The grain morphology and texture control in electron beam melted (EBM) Ti-47Al-8Nb γ-TiAl alloy is considered. The EBM process window to obtain a columnar lamellar colony (CLC) grain structure was ...defined following a critical assessment of thermal gradient and liquid-solid interface velocity by using numerical simulation. Experimentally, an epitaxial grain growth during solidification of Ti-47Al-8Nb has been realised by using the optimum EBM parameter sets. The length of the CLC grain structure reached up to ∼600 μm (compared to the powder layer thickness of 70 μm). The texture analysis and phase identification performed using electron backscatter diffraction (EBSD) provided important insights in understanding the solidification and phase transformation processes during the EBM fabrication. It was found that the solidification path for EBM high Nb-TiAl alloy involves the high-temperature α-phase field (i.e. L+β→α and α→α2+γ phase transformation processes). The epitaxial growth of prior β grains and the anchoring effect of residual B2-phase are very likely to be responsible for the formation of CLC microstructure.
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•We provide a new method to overcome the difficulty of lamellar orientation control caused by the uncertain orientations of α phase generated from β→α solid phase transformation between adjacent layers during EBM.•With the tight control of both thermal gradient and velocity of solidification front, EBM of high Nb-TiAl alloy produced a highly columnar prior β grain structure within which the presence of γ/B2 lamellae and extended lamellar colonies along the Z-direction was found.•The length of the columnar lamellar colony structure reached up to ∼600 μm (compared to the powder layer thickness of 70 μm).
High-performance and long-pulse operation is a crucial goal of current magnetic fusion research. Here, we demonstrate a high-connement plasma regime known as an H-mode with a record pulse length of ...over 30 s in the Experimental Advanced Superconducting Tokamak sustained by lower hybrid wave current drive (LHCD) with advanced lithium wall conditioning. We nd that LHCD provides a exible boundary control for a ubiquitous edge instability in H-mode plasmas known as an edge-localized mode, which leads to a marked reduction in the heat load on the vessel wall compared with standard edge-localized modes. LHCD also induces edge plasma ergodization that broadens the heat deposition footprint. The heat transport caused by this ergodization can be actively controlled by regulating the edge plasma conditions. This potentially offers a new means for heat-ux control, which is a key issue for next-step fusion development. PUBLICATION ABSTRACT
A new type of plastic near‐infrared photodetector utilizing low band gap polymer (see figure) is presented. When composing the detector in a donor‐acceptor type energy band structure and operating it ...in the reverse bias condition (less than 5 V), the photodetector shows respectable performance: external quantum efficiency exceeding 38 %, bandwidth of 4 MHz and the noise equivalent power of 3.85 × 10–12 W Hz–1/2 at 850 nm.
The diagnosis of type 1 diabetes mellitus (DM) in humans is associated with high altitude, few sunshine hours, cold climate, and winter. The goals of this study were to investigate seasonal and ...geographic patterns of DM diagnosis in United States of America (USA) dogs with juvenile and mature onset DM. Data were collected by means of an online survey widely distributed in the USA through breed clubs, academic veterinary institutions, private veterinary referral practices, social media outlets, and the American Kennel Club. Juvenile DM (JDM) and mature onset DM were defined as DM with an age of onset <365 days and DM with an age of onset ≥365 days, respectively. Meteorological seasons were defined as: winter from December through February, spring from March through May, summer from June through August, and fall from September through November. Four geographic regions were also defined as the West, North, South, and Central regions of the USA. Nonoverlapping 95% confidence intervals (CI) for season, geographic region, and breed specific proportions of dogs with JDM were considered statistically significantly different. The study included 933 dogs with mature onset DM and 27 dogs with JDM. Dogs were diagnosed with DM significantly more in the winter and northern USA compared to all other seasons and all other geographic regions, respectively. The prevalence of JDM among dogs with DM was 2.8%. The proportion of dogs with JDM among pure breeds was not significantly different than the proportion of JDM in mixed breed dogs. It is concluded that winter and cold climate could be shared environmental factors influencing DM expression in dogs and humans. Additionally, pure breed dogs do not appear to be at increased risk for JDM compared to mixed breed dogs, indicating that factors other than genetics could influence spontaneous JDM development in dogs.
Enterococcus faecalis is an important contributor to the persistence of chronic apical periodontitis. However, the mechanism by which E. faecalis infection in the root canals and dentinal tubules ...affects periapical tissue remains unclear. Bacterial extracellular vesicles (EVs) act as natural carriers of microbe-associated molecular patterns (MAMPs) and have recently attracted considerable attention. In this study, we investigated the role of EVs derived from E. faecalis in the pathogenesis of apical periodontitis. We observed that E. faecalis EVs can induce inflammatory bone destruction in the periapical areas of mice. Double-labeling immunofluorescence indicated that M1 macrophage infiltration was increased by E. faecalis EVs in apical lesions. Moreover, in vitro experiments demonstrated the internalization of E. faecalis EVs into macrophages. Macrophages tended to polarize toward the M1 profile after treatment with E. faecalis EVs. Pattern recognition receptors (PRRs) can recognize MAMPs of bacterial EVs and, in turn, trigger inflammatory responses. Thus, we performed further mechanistic exploration, which showed that E. faecalis EVs considerably increased the expression of NOD2, a cytoplasmic PRR, and that inhibition of NOD2 markedly reduced macrophage M1 polarization induced by E. faecalis EVs. RIPK2 ubiquitination is a major downstream of NOD2. We also observed increased RIPK2 ubiquitination in macrophages treated with E. faecalis EVs, and E. faecalis EV-induced macrophage M1 polarization was notably alleviated by the RIPK2 ubiquitination inhibitor. Our study revealed the potential for EVs to be considered a virulence factor of E. faecalis and found that E. faecalis EVs can promote macrophage M1 polarization via NOD2/RIPK2 signaling. To our knowledge, this is the first report to investigate apical periodontitis development from the perspective of bacterial vesicles and demonstrate the role and mechanism of E. faecalis EVs in macrophage polarization. This study expands our understanding of the pathogenic mechanism of E. faecalis and provides novel insights into the pathogenesis of apical periodontitis.
Using two flexible Schiff bases, H2L1 and H2L2, two new cobalt II (Co(II))-coordination compounds, namely, Py3CoL1 (1) and Py3CoL2 (2) (Py=pyridine, L1=3,5-ClC6H2(O)C=NC6H3(O)-4-NO2, ...L2=3,5-BrC6H2(O)C=NC6H3(O)-4-NO2) have been synthesized under solvothermal conditions. Single crystal X-ray structural analysis revealed that compounds 1 and 2 are both six-coordinate in a distorted octahedral geometry, and the 1D chain structure was formed by the π…π and C-H…O interactions or C-H…Cl interaction. The in vitro antitumor activities of 1, 2 and their corresponding organic ligands Py, L1, and L2 were studied and evaluated, in which three human skin cancer cell lines (A-431, HT-144 and SK-MEL-30) were used in the screening tests.
During recent decades, China has experienced a rapid growth in economy and also in prevalence of childhood obesity. Given the great importance of adolescence overweight/obesity for future health and ...given the relative lack of longitudinal studies on adolescent obesity in developing countries, particularly in China, in this study, we aimed to explore the potential growth trajectories of overweight/obesity among Chinese adolescents and to further examine socio-economic status predictors and health consequences of these growth trajectories.
This study is a longitudinal study.
The data were from four waves of panel data from the China Family Panel Studies (CFPS 2010, 2012, 2014, and 2016). For the present study, children aged 10 to 12 years from the baseline 2010 sample were selected (N = 1685), among whom 1388 were reinterviewed in 2012, 1172 in 2014, and 941 in 2016. We retained a final sample of 800 who had at least three waves of body mass index (BMI) data (i.e. final N = 800). Generalized growth mixture modeling was used as the major analytical strategy.
We found three different types of overweight/obesity developmental trajectories for these Chinese adolescents, namely a stably normal class, a decreased risk class, and a chronically overweight/obese class. Moreover, we found that higher family income was associated with a lower probability of getting into the chronically overweight/obese class for urban adolescents but with a higher probability of getting into the same class for rural adolescents. Lastly, the adolescents classified in the chronically overweight/obese group reported significantly lower levels of self-rated health.
There were heterogeneous growth trajectories of adolescent overweight/obesity in China. Sustained overweight/obesity during adolescence was predicted by lower family income in urban China but by higher family income in rural China. More targeted and regionalized interventions for childhood overweight/obesity in China should be considered.
•Three types of overweight/obesity developmental trajectories were found for Chinese adolescents.•Sustained overweight/obesity during adolescence was predicted by lower family income in urban China but by higher family income in rural China.•The adolescents in the chronically overweight/obese group reported significantly lower levels of self-rated health.•Urban and rural China may be experiencing different stages of nutrition transition.
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