Recently developed classes of electronics for biomedical applications exploit substrates that offer low elastic modulus and high stretchability, to allow intimate, mechanically biocompatible integration with soft biological tissues. A challenge is that such substrates do not generally offer protection of the electronics from high peak strains that can occur upon large-scale deformation, thereby creating a potential for device failure. The results presented here establish a simple route to compliant substrates with strain-limiting mechanics based on approaches that complement those of recently described alternatives. Here, a thin film or mesh of a high modulus material transferred onto a prestrained compliant substrate transforms into wrinkled geometry upon release of the prestrain. The structure formed by this process offers a low elastic modulus at small strain due to the small effective stiffness of the wrinkled film or mesh; it has a high tangent modulus (e.g., >1000 times the elastic modulus) at large strain, as the wrinkles disappear and the film/mesh returns to a flat geometry. This bilinear stress–strain behavior has an extremely sharp transition point, defined by the magnitude of the prestrain. A theoretical model yields analytical expressions for the elastic and tangent moduli and the transition strain of the bilinear stress–strain relation, with quantitative correspondence to finite element analysis and experiments.

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Objective To analyze if general factors such as age, gender, dominant side, fasting blood sugar level, BMI (body mass index), smoking, and drinking play a role in graft resorption after arthroscopic autologous scapular spine bone grafting. Methods From July 2016 to August 2018, patients who were diagnosed with anterior shoulder instability with subcritical bone loss (10%–15%) and underwent arthroscopic autologous scapular spine bone graft transplant were retrospectively reviewed and enrolled in this study. The age, gender, dominant side, fasting blood sugar level, BMI, smoking, and drinking conditions of the enrolled patients were recorded. The graft resorption rate at postoperative 1 year was also measured on three‐dimensional computed tomography (3D‐CT) scans. The Pearson test and the Spearman test were used to identify any significant correlation between the general factors and graft resorption rate. Results A total of 27 patients who underwent arthroscopic autologous scapular spine bone graft for recurrent shoulder instability qualified and were included in this study. There were 20 males and seven females, the mean age was 30.8 ± 9.4 years, the mean follow‐up time was 29.3 months (range, 25–39 months), during which no severe complications such as infection, neurovascular injury, or re‐dislocation were observed. The bone graft healed in all cases, the mean healing time was 2.6 ± 0.5 months (range, 2–3 months). At the last follow‐up, the mean Constant–Murley score was 89.74 ± 3.71, the mean Disabilities of Arm, Shoulder and Hand (DASH) score was 9.77 ± 5.31, and the mean visual analogue score (VAS) was 0.74 ± 0.64. The apprehension test was all negative at final follow‐up. The fasting blood sugar level was 4.78 ± 0.42 mmol/L, BMI was 23.70 ± 4.70. Five patients were “smoking” and 22 “non‐smoking”, four patients were “drinking” and 23 were “non‐drinking.” The graft resorption rate at postoperative 1 year was 19.4% ± 7.5%. The Pearson test and the Spearman test showed no significant correlation between age, gender, dominant side, fasting blood sugar level, BMI, smoking, drinking, and graft resorption rate. Conclusion Age, gender, dominant side, fasting blood sugar level, BMI, smoking, and drinking were not significantly correlated with graft resorption after the arthroscopic autologous scapular spine bone graft for recurrent shoulder instability.

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Background Horner syndrome (HS), mainly characterized by symptoms including ptosis, miosis, and anhidrosis on the affected face, is a condition that is well documented but rarely reported as a postoperative complication of thyroidectomy, particularly in endoscopic thyroid surgery (ETS). We hereby report a case of HS due to ETS with a brief literature review on this topic. Case presentation A 31-year-old female was admitted to our hospital with an unexpected physical examination finding of two thyroid nodules that were hypoechoic, had an irregular shape, and exhibited calcification. Subsequently, the results of a fine-needle aspiration (FNA) biopsy from the thyroid nodules and BRAFV600E mutation further confirmed the malignancy of these nodules. Thus, total thyroidectomy combined with central lymph node dissection (CLND) by ETS via the bilateral axillo-breast approach was performed on this patient. Histology confirmed the diagnosis of papillary thyroid microcarcinoma (PTMC) concurrent with Hashimoto’s thyroiditis (HT). However, this patient developed HS with ptosis in her left eye on postoperative day 3. All symptoms gradually resolved before the 3-month follow-up. Conclusion HS subsequent to ETS is a rare complication. Thus, standardized and appropriate operative procedures, as well as subtle manipulation, are essential in preventing and reducing the occurrence of HS. In addition, the early diagnosis and management of this rare complication are also important for a favorable outcome.

Practical application of three-dimensional (3D) Magnetotelluric (MT) inversion requires efficient forward modeling of electromagnetic (EM) fields in the Earth. To resolve realistic 3D structures, large computational domains and extremely large linear systems of equations are required. The iterative solvers, which are almost exclusively used to solve these systems can be inefficient due to the abundant null space of the curl-curl operator. Multigrid (MG) solvers are considered a potentially efficient technique for solving such problems. However, due to the abundant null solution space and existence of the air layer, MG solvers can still converge slowly, or even diverge. We develop an efficient MG solver for finite difference (FD) frequency domain EM solution. In this algorithm, the excellent smoothing property of an efficient 4-color cell-block Gauss-Seidel (GS) is exploited to remove the short-range errors effectively, and the interpolation and prolongation operators are utilized to handle the long-range errors. They work as a whole to speed the convergence of our proposed algorithm remarkably. Since all the nodes for the 4-color cell-block GS are grouped into four colors and in each color the edge components attached to different nodes are totally decoupled, this can be utilized to develop a highly vectorized or parallelized algorithm. Another important property is that our algorithm is locally current divergence free, effectively eliminating spurious solutions in the null space of the curl-curl operator. The accuracy and efficiency of the algorithm are verified by comparing the numerical solutions obtained with our MG solver with those from the Bi-Conjugate Gradients Stabilized (BiCGStab) solver with different preconditioners based on synthetic models and a model from 3D inversion. Comparisons, in terms of iteration number and computational time, indicate that our algorithm is extremely stable and efficient relative to the other solvers. Our MG algorithm will as well be suitable for massively parallel computing.

<p>In snow-dominated regions, snowmelt water plays a critical role in recharging the subsurface and generating streamflow. With a changing climate, the fraction of annual precipitation that falls as snow will probably decline. Rainfall and snowmelt water have different interactions with the subsurface and potentially vegetation, thus affecting the partitioning of precipitation into subsurface storage and streamflow. Currently, our understanding of how snow-to-rain transition affects this hydrologic partitioning in mountainous catchments is still limited. To take the best management practices for climate change adaptation, it is of critical importance to study how a catchment responds to such environmental disturbances.</p> <p>In this study, we use the geophysics-informed hydrologic modeling to study the effect of snow-to-rain transition on hydrologic partitioning in a snow-dominated mountainous catchment in Idaho, USA. In the modeling, the subsurface structure was extracted from velocity map obtained from seismic refraction tests. Many studies has highlighted the importance of the heterogeneous subsurface in water partitioning in catchments, but accurate characterizations with traditional field techniques such as drilling are challenging. The hydrologic model developed from geophysical results is then calibrated with historical hydrometeorological measurements. Two climate change scenarios are designed to study the impact of warming on streamflow generation and water storage. In Scenario 1, a uniform warming is considered throughout the year, and an air temperature increase (+2.5 °C) is applied to change the phase of precipitation. In scenario 2, warming is only applied to the snow season (i.e., from December to April). The numerical modeling results show that a uniform warming (scenario 1) significantly promotes evapotranspiration (ET), and streamflow becomes less productive. Warming in the snow season only (scenario 2) induces an earlier, flashier streamflow but the partitioning of precipitation between storage and streamflow is not significantly changed. Compared to simulation results from traditional hydrologic modeling (without the heterogeneous deep subsurface), geophysics-informed hydrologic modeling reveals the importance of water storage in the fractured bedrock in response to the climate change.</p>

Effect of Ni-based conversion coating and Ni-Pelectroless plating on the bonding process of pure Al and AZ31alloyFor the first time, the present study investigates the preparation of Al/Mg bimetal using Ni-based conversion plating and Ni -P electroless plating by means of diffusion bonding. In this study, AZ31 alloy was coatedwith an Ni-based interlayer by conversion plating and an Ni -P interlayer by electroless plating; the Al/Mg bimetallic materialsw ere prepared by diffusion bondingi na na ir atmosphere. For conversion plating, the thickness of the Ni-based layer is severalh undred nanometers. When heat-treated at 450 8 C for 90 min, most of the interfaces between Al and AZ31 alloy bondt ogether well. For electroless plating, the thickness of the Ni -P layer is about 10 l mfor aplating time of 60 min. When heat-treated at 450 8 Cf or 150 min, good bondingbetween pure Al and AZ31 can be obtained.