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This study aims to evaluate the accuracy of L-shaped reduction malarplasty with bone setback or resection on the zygoma and the mortice and tenon joint structure on the zygomatic arch under the guidance of virtual surgical planning (VSP). Adult patients with zygomatic protrusion or hypertrophy were enrolled and divided. L-shaped reduction malarplasty with or without bone resection and with the mortice and tenon joint structure on the zygomatic arch was conducted either by digital procedures comprising VSP and three-dimensional (3D) printing titanium templates (Group I) or by conventional methods (Group II). Positions of representative landmarks and superimposition models were analyzed by 3D cephalometry. Satisfaction rate and incidences of clinical complications were compared as well. Satisfactory reduction of zygomatic protrusion or hypertrophy was recognized among all 78 patients. Improved symmetry and great surgical accuracy were observed according to the cephalometry analyses. The bone segment movement of virtual plans and actual results in Group I were measured and showed no obvious difference for the inward movement (5.42 ± 0.98 mm vs. 5.33 ± 0.93 mm, P = 0.6906) and the sagittal overlap (4.77 ± 1.32 mm vs. 4.87 ± 1.21 mm, P = 0.7386) at the zygoma roots, along with the step length at the long-arm of the L-shaped osteotomy line (2.43 ± 1.11 mm vs. 2.39 ± 0.89 mm, P = 0.8665). The high resemblance between virtual plans and actual results was depicted via superimposition models. Meanwhile, a higher satisfaction rate (28 in 36, 78% vs. 20 in 42, 48%) and a lower incidence rate of complications (11 in 36, 31% vs. 21 in 42, 50%) were found in Group I. Within the limitations of the study it seems that the application of VSP in reduction malarplasty could significantly contribute to better surgical accuracy and reduced difficulties in the operation, which would be beneficial to patients with zygoma hypertrophy or prominence. [ABSTRACT FROM AUTHOR]

Reduction malarplasty is one of the most popular procedures for esthetic facial contouring in East Asians. The retrospective observational study aimed to analyze the association between the zygomatic change and bone setback or resection to propose quantitative guidance for L -shaped reduction malarplasty based on computed tomographic (CT) images. A retrospective observational study was conducted on patients who underwent L -shaped reduction malarplasty with bone resection (Group I) or without bone resection (Group II). The amount of bone setback and resection was calculated. The unilateral width changes of the anterior, middle, and posterior zygomatic regions as well as zygomatic protrusion change were also evaluated. Pearson correlation analysis and linear regression analysis were used to analyze the relationship between the bone setback or resection and the zygomatic changes. Eighty patients who underwent L -shaped reduction malarplasty were included in this study. Significant correlation was observed between the bone setback or resection and the change of anterior, and middle zygomatic width as well as protrusion in both the two groups (P <.001). The correlation between bone setback or resection and the posterior zygomatic width change was not significant (P ＞.05). The bone setback or resection of L -shaped reduction malarplasty lead to the anterior and middle zygomatic width and zygomatic protrusion changes. Furthermore, the linear regression equation can be referenced as a guidance for a preoperative surgical plan. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare two kinds of reduction malarplasty in terms of their bony consolidation. Patients that underwent reduction malarplasty were reviewed retrospectively. The medial movement of the zygomatic body and the zygomatic arch as well as the complications and satisfaction of patients were investigated. The surgical procedure entailed a classical or modified L-shaped osteotomy through intraoral and sideburn approaches. Two groups were distinguished, those for whom a mortice and tenon joint was formed on the zygomatic arch (Group I), and those that formed end-to-end bone contact (Group II). All the cases in Group I showed an improved facial contour with sufficient bone contact. A larger medial movement of the zygomatic arch was observed in Group I (4.54 ± 0.41 mm) than in Group II (2.72 ± 0.29 mm) (P = 0.016). More bone malunion was observed in six cases of Group II (P = 0.030) and four required a second operation. In conclusion, this study indicates that the mortice and tenon approach is preferable when the priority is bony consolidation. [ABSTRACT FROM AUTHOR]

To reduce the friction, wear, and temperature of the piston-cylinder liner friction pair, we designed and processed 27 kinds of bio-inspired textured pistons with cylindrical pits. Based on the experimental optimization design method, friction test, wear test, and thermal imaging test were carried out. Results show that the textured pistons can significantly reduce the friction. Various texture parameters have different effects on the mean friction force. The wear of the textured pistons is significantly less than that of the standard piston. The influence of the texture parameters on piston wear are analyzed through range analysis, regression equation, and 3D response surface method. The standard piston suffers from serious wear and tear. The cylindrical pit texture can supply lubrication and store abrasive particles, which can improve the wear condition of the textured piston surface to a certain extent. The friction heat of the textured pistons is small, which can reduce the average temperature of the friction pair. • Inspired by earthworms and leeches, 27 kinds of textured pistons with cylindrical pits were designed and fabricated. • The wear of the textured pistons is significantly less than that of the standard piston. • The cylindrical pit texture can supply lubrication and store abrasive particles, which can improve the wear condition of the textured piston surface to a certain extent. • The cylindrical pit texture can supply lubrication, store abrasive particles, and improve the wear condition to a certain extent. [ABSTRACT FROM AUTHOR]

Abstract Reliable operating conditions of hydrostatic turntables are prerequisite to ensuring machine tool performance. The hydrostatic turntable is affected by multiple working conditions, therefore, methods for evaluating turntable load-carrying capacity has become research hotspot. In this paper, by analyzing bearing capacity, parameters closely related to the support performance of turntables are selected as recognition features and an artificial neural network (ANN) training method is proposed. The ANN method is based on numerical solutions of over-determined nonlinear equations (ODNE) to intelligently evaluate turntable performance. In this study, ANN and ODNE training are applied to evaluate the performance of hydrostatic turntables. Finally, to verify the feasibility of the method, an intelligent monitoring system is established to collect data on machine tools. Highlights • Factors influencing the performance of hydrostatic turntable were determined by analyzing the carrying ability of oil pads. • Based on the ANN structure for fast calculation of optimal weights, an ODNE training method was presented. • For intelligent monitoring of a hydrostatic turntable, BP and ODNE training are both recommended for training the ANN. [ABSTRACT FROM AUTHOR]

Understanding and harnessing the coupling between lubrication pressure and elasticity provides materials design strategies for applications such as adhesives, coatings, microsensors, and biomaterials. Elastic deformation of compliant solids caused by viscous forces can also occur during dynamic force measurements in instruments such as the surface forces apparatus (SFA) or the atomic force microscope (AFM). We briefly review hydrodynamic interactions in the presence of soft, deformable interfaces in the lubrication limit. More specifically, we consider the scenario of two surfaces approaching each other in a viscous fluid where one or both surfaces is deformable, which is also relevant to many force measurement systems. In this article the basic theoretical background of the elastohydrodynamic problem is detailed, followed by a discussion of experimental validation and considerations, especially for the role of elastic deformation on surface forces measurements. Finally, current challenges to our understanding of soft hydrodynamic interactions, such as the consideration of substrate layering, poroelasticity, viscoelasticity, surface heterogeneity, as well as their implications are discussed. [ABSTRACT FROM AUTHOR]

The resistance of fluid infusion inside a thin film that separates an opening gap leads to viscous adhesion. Viscous adhesion can be detrimental for some mechanical devices such as valves or during additive manufacturing processes. On the other hand, it is also a mechanism found in nature for dynamic reversible adhesion. In this article we review analysis and measurements of viscous adhesion. In particular, we give conditions where viscous adhesion dominates over other surface forces. We also describe how characteristics of the solid surfaces such as roughness and elasticity, as well as the compliance of the load cell can be incorporated in the analysis. Finally, we discuss the knowledge gaps and scientific areas where a better understanding of viscous adhesion could be beneficial. Image 1 [ABSTRACT FROM AUTHOR]

• In this article, we systematically reviewed and analyzed COVID-19 trends, policies and vital epidemiological indicators, quantifying the impact of COVID-19 on electricity consumption. • We introduced a data-driven approach to predict the electricity consumption in non-COVID-19 scenario. • We bridged the knowledge gap between key energy and epidemiological parameters, finding a statistic correlation between energy loss and effective reproductive number (R t). In addition to the tremendous loss of life due to coronavirus disease 2019 (COVID-19), the pandemic created challenges for the energy system, as strict confinement measures such as lockdown and social distancing compelled by governments worldwide resulted in a significant reduction in energy demand. In this study, a novel, quantitative and uncomplex method for estimating the energy consumption loss due to the pandemic, which was derived from epidemiological data in the beginning stages, is provided; the method bonds a data-driven prediction (LSTM network) of energy consumption due to COVID-19 to an econometric model (ARDL) so that the long- and short-term impact can be synthesized with adequate statistical validation. The results show that energy loss is statistically correlated with the time-changing effective reproductive number (R t) of the disease, which can be viewed as quantifying confinement intensity and the severity of the earlier stages of the pandemic. We detected a 1.62% decrease in electricity consumption loss caused by each percent decrease in R t on average. We verify our method by applying it to Germany and 5 U.S. states with various social features and discuss implications and universality. Our results bridge the knowledge gap between key energy and epidemiological parameters and provide policymakers with a more precise estimate of the pandemic's impact on electricity demand so that strategies can be formulated to minimize losses caused by similar crises. [ABSTRACT FROM AUTHOR]