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Background: Unbalanced alterations of temporomandibular joint morphology were associated with unilaterally masticatory habits. Objective: This study aimed to investigate the effect of unilateral mastication on the remodelling of the temporomandibular joint using dynamic joint space. Methods: Twelve volunteers with non‐maxillofacial deformity and healthy temporomandibular joints were recruited. The 3D models of the mandible and the maxilla were reconstructed according to computed tomography. The subjects were asked to masticate French fries and peanuts unilaterally, which was recorded by a 3D motion capture system. The dynamic joint space during unilateral mastication was analysed. Results: During early closure, the joint space reduction on the non‐masticatory side was significantly greater than on the masticatory side (p <.05). During later closure, the joint space reduction on the non‐masticatory side was significantly lower than that on the masticatory side (p <.05). The difference in joint space reduction between both sides was greater than the French fries while masticating the peanuts. Conclusions: Unilateral mastication resulted in a different major pressure area on the bilateral TMJs. Therefore, unilateral mastication might be an essential factor in the bilateral asymmetrical remodelling of the TMJ. [ABSTRACT FROM AUTHOR]

Ultrasmall metal nanoclusters (NCs) exhibit a quantized conduction band, hence, a distinct HOMO‐LUMO gap (Eg). Such a quantized electronic structure gives rise to multiple discrete peaks in the optical absorption spectrum of the NCs. As the size grows to 130 gold atoms (Au130 protected by ligands), electrical charging and optical behaviors seem to show certain metal‐like features (hence, transition‐sizes). To probe such behaviors, especially the potential ligand effect, we have devised the synthesis of Au130 NCs protected by phenylethanethiolate and naphthalenethiolate, respectively, with the former having a nonconjugated separation between the aromatic molecular group and the metal core while the latter being in direct bonding. A careful comparison of these two Au130 nanoclusters with the earlier reported analogues is carried out, including the structurally characterized Au130(pMBT)50 and the aqueous counterpart. While all of these nanoclusters possess the same 80 free electron counts in the core, some notable differences in electrochemical and optical properties are found, which are attributed to the ligand effects. The obtained insights may stimulate further interest in the transition‐sized nanoclusters and also promote their applications in optics, energy conversion, and biomedicine. [ABSTRACT FROM AUTHOR]

The Fourier–Merlin transform method, multi-scale optical flow method, and Weibull distribution are used to integrate the GRAPES_3 km model and Radar Extrapolation Forecast (REF) both developed independently by China. Taking GRAPES_3 km, Wuhan Rapid Update Cycle (WHRUC), and the REF as examples, the prediction performance of the Blending forecast is evaluated comprehensively by the traditional point-to-point method. A new spatial test method is introduced to evaluate the applicability and difference of high-resolution model evaluation. The area, position, shape, and intensity of the precipitation area are matched through the target object test method. The potential forecast information of the spatial field is obtained and the related results are compared and analyzed. The results show that: (1) the comprehensive application of various evaluation methods can evaluate the convective storm forecast more comprehensively. The Blending forecast effect is obviously better than those of other models by using the point-to-point scoring method, especially in the heavy precipitation forecast. The shorter the prediction time is, the better the effect is. (2) The new spatial test method can evaluate the prediction effect of convective storm characteristics, and the target recognition hit rate of the Blending forecast is highest. The scores of target area, position, shape, and median intensity of precipitation are better than those of other forecasts. The variation in the east–west direction is less than that in the north–south direction, which is basically consistent with the actual observation. The variation range of the forecast grid before and after translation is the closest to the reality. (3) The Blending forecast method combines the advantages and disadvantages of the numerical model and REF, which can not only grasp the precipitation area but also improve the prediction ability of rainfall intensity. The traditional point-to-point scoring method and the new spatial test method have the same conclusion as the convective storm forecast of the high-resolution model, which has a certain reference value, and the new spatial test method can provide more detailed evaluation information. [ABSTRACT FROM AUTHOR]

This paper studies the influence of degraded connections on dynamic characteristics, seismic response, and seismic fragility behaviors of traditional Chinese timber-framed buildings. Numerical models are developed based on the extended distinct element method, and calibrated with 1:3.52 scaled shake-table test data. The influence of fracture and wood aging on the performance of both mortise-tenon joints and Dougong brackets connections is discussed. A set of 20 ground motion records are selected for an incremental dynamic analysis, seismic behaviors, and fragility assessment. Results indicate that considering 0.75 times and 0.85 times degradation of mortise-tenon joints, natural frequencies are reduced by 8%, and 4%, respectively, and 4%, and 2% for Dougong brackets connections, respectively. The maximum acceleration response is reduced at most by 1.8% and 0.9%, respectively, and the maximum relative displacement is promoted by 7.3% and 5.3%, respectively. In addition, for a peak inter-structural layer drift of 1/442, 1/148, and 1/48, seismic intensities corresponding to median probabilities of exceedance of the structure with 0.75 times degraded performance of mortise-tenon joints are reduced by 32%, 16%, and 9%, respectively, and 14%, 6%, and 3% for Dougong bracket connections. [ABSTRACT FROM AUTHOR]

Orthognathic surgery is a typical approach for treating maxillofacial deformities. However, orthognathic surgery results in positional changes in the condyles. In a previous review, the effects of orthognathic surgery on temporomandibular joints (TMJs) are not provided. Hence, in this study, we investigate the morphological changes in TMJs after mandibular and bi-maxillary osteotomies. The relationship between the morphological parameters of TMJs and symptoms of temporomandibular disorders (TMDs) is discussed. Finite element contact stress analysis is performed, and the results show that the two abovementioned surgeries can improve maxillofacial deformities, although the positions of the condyles are changed. Moreover, preoperative stress asymmetry of the left and right TMJs is observed, which remain after the surgeries. TMD patient-specific analysis shows that three joint spaces (medial joint space, lateral joint space, superior joint space) are significantly correlated with TMD symptoms. [ABSTRACT FROM AUTHOR]

Alloying is an important strategy in tailoring the functionality of materials. In metal nanoclusters (NCs), the introduction of a heterometal leads to alloy nanoclusters that often outperform the homometal ones in terms of the physical and chemical properties. In this work, a series of four M144(PET)60 alloy NCs (where, M = Au/Ag, PET = −SCH2CH2Ph) are synthesized and characterized. The silver doping into the homogold template (Au144) leads to more prominent optical absorption features in the steady-state spectrum in the visible range. Femtosecond transient absorption spectroscopy reveals the effect of Ag doping on the electronic relaxation dynamics compared to Au144 and the pump fluence independent dynamics. Electrochemical results reflect a narrowing of HOMO—LUMO gap (Eg) induced by Ag doping. A temperature dependence of the single-electron charging is also observed for the series of alloy NCs, in which the Eg values of the alloy NCs enlarge as the temperature decreases, which is characteristic of semiconducting behavior. [ABSTRACT FROM AUTHOR]

This paper studies the effect of performance degradation and infilled walls on the seismic fragility of a traditional Chinese timber-frame structure. The Yihe Hall was chosen as the archetype building and extended distinct element method (EDEM) models of the structures were developed using the Wallstat software. Validation of the timber frame and the whole structure were conducted, respectively. For this study, a set of 20 ground motion records were selected for the incremental dynamic analysis (IDA). Results indicate that the performance degradation of the structure significantly reduces the probability of basically intact by 18%, and increases the collapse probability by 10%. In addition, the infilled walls highly promote the probability of basically intact by 36%, and decrease the collapse probability by 7%. This study indicates that from the protection point of view, it is necessary to repair and strengthen the ancient timber structures with degraded performance to meet the reliability requirements. From the view of seismic evaluation, the coordinated seismic effect of the walls and the frame should be fully considered. [ABSTRACT FROM AUTHOR]