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In this study, we investigate the differences between two transient, three-dimensional, thermomechanically coupled ice-sheet models, namely, a first-order approximation model (FOM) and a ‘full’ Stokes ice-sheet model (FSM) under the same numerical framework. For all numerical experiments, we take the FSM outputs as the reference values and calculate the mean relative errors in the velocity and temperature fields for the FOM over 100 years. Four different boundary conditions (ice slope, geothermal heat flux, basal topography and basal sliding) are tested, and by changing these parameters, we verify the thermomechanical behavior of the FOM and discover that the velocity and temperature biases of the FOM generally increase with increases in the ice slope, geothermal heat flux, undulation amplitude of the ice base, and with the existence of basal sliding. In addition, the model difference between the FOM and FSM may accumulate over time, and the spatial distribution patterns of the relative velocity and temperature errors are in good agreement.

Pallet recognition is one of the critical technologies of cargo handling for unmanned industrial vehicles. A pallet recognition method based on adaptive color fast point feature histogram (ACFPFH) is proposed to solve the problems of current recognition methods such as low efficiency, time-consuming, poor robustness and random parameter selection. The Kinect V2 sensor is used to collect the point cloud data which represents the whole scene including pallet. Next, outliers are removed and the optimal neighborhood radius of each point is obtained based on the minimum criterion of neighborhood feature entropy function. Then, the key points are extracted from scene point clouds. The ACFPFH consisting of color feature and adaptive geometric feature is applied for similarity matching between the template and scene point clouds. Finally, wrong feature correspondences are rejected and the pallet in the scene point cloud is recognized. A comparison of the fast point feature histogram with the fixed neighbor radius of 0.012 m shows that the pallet recognition precision and efficiency of the method based on ACFPFH is improved by 83.74% and 35.55% respectively, which verifies the superiority of the proposed method.

Objective To investigate the value of high-gamma oscillations (65~100 Hz) in epileptogenic foci localization by analyzing the intraoperative electrocorticography (ECoG) in patients with refractory temporal lobe epilepsy, along with comparing the occurrence rate and distribution characteristics of high-gamma activity as well as spike wave inside and outside the irritative zone and around the foci. Methods A retrospective analysis was carried out on the intraoperative ECoG data of 21 patients with refractory temporal lobe epilepsy in our hospital from January 2013 to January 2019. The channels with interictal epileptiform discharges (IEDs) were defined as irritated area, and those without IEDs as non-irritated area. Based on the preoperative imaging data, intraoperative navigation combined with neurosurgeon's judgment, the monitoring cortical area was divided into focal area, perifocal area and the area away from the focus. Then the occurrence rate and distribution characteristics of IEDs (filter range: 1~30 Hz) and high-gamma were compared, and the distribution of high-gamma activity inside and outside the irritated area, and the incidence of high-gamma around the foci were analyzed. Results ① The overall incidence of IEDs and of high-gamma in the 21 patients were both 100.0% (21/21), and the average number of channels for IEDs, high-gamma and gamma+IEDs was 9.50±2.80, 8.14±2.93 and 6.60±2.40, respectively, indicating notably more IEDs channels than the other 2, by RM one-way ANOVA (P < 0.05). ②The channel numbers of high-gamma were 6.60±2.40 and 1.50±1.30 in the irritated and non-irritated areas respectively, and the event rates were 0.42±0.30 and 0.20±0.20 respectively, showing significant difference between the 2 areas (P < 0.01). ③The event numbers of high-gamma activity were 46.00±42.00, 33.40±32.90 and 8.40±9.40 in the focal area, the perifocal area and the area away from the focus, respectively, with the corresponding event rate of 0.40±0.30, 0.37±0.38 and 0.10±0.10, respectively. There were no significant differences in the event numbers and rates between the focal and perifocal area, though they were both significantly higher than that of the area away from the focus, by paired t-test (P < 0.05). Conclusion Traditional IEDs of ECoG are still an important marker to guide the range of resection intra-operatively in epilepsy surgery, while high-gamma presents great consistency with both IEDs and foci, with more accurate identification of epileptogenic zone than IEDs. Therefore, IEDs combined with high-gamma may have greater value in the localization of epileptogenic zone.

doi：10.3969/j.issn.1672⁃6731.2021.11.016

Objective To evaluate the clinical effectiveness of bilateral subthalamic nucleus (STN) deep brain stimulation (DBS) in treatment of levodopa-induced dyskinesia (LID) in patients with Parkinson's disease (PD), and to explore the feasibility and the possible underlying mechanism of the treatment. Methods A retrospective review was conducted on all the PD patients who underwent STN-DBS in our department from March 2016 to December 2019. Unified Parkinson's Disease Rating Scale (UPDRS) part Ⅲ and part Ⅳ, dyskinesia subscore (items 32 to 34 of UPDRS part Ⅳ) and the levodopa equivalent daily dose (LEDD), which were used to evaluate the improvement of the symptoms before and in 6 months after operation. Results In 6 months after STN-DBS, the LID symptoms of the 12 patients finally enrolled were significantly improved, with the improvement rates of UPDRS Ⅳ score and dyskinesia subscore of (45.91±13.01)% and (61.96±22.03)%, respectively. Among them, the LEDD was maintained in 2 patients, and reduced in the other 10 patients, with the averagely reduced rate of 43.58%, and the highest rate of 72.00%. Meanwhile, the motor symptoms of all patients were also significantly improved, and the improvement rate of UPDRS Ⅲ score was (68.14±9.51)%. Conclusion STN-DBS significantly improves dyskinesia symptom of PD patients. Its anti-dyskinesia effect may be not only related to reduction of drug dose, but also to direct inhibition of LID.

Objective To investigate whether there is a significant difference in the accuracy of the two-sided electrode implanted during the same period in Parkinson's disease (PD) with subthalamic nucleus deep brain stimulation (STN-DBS), and whether the accuracy affects the bilateral postoperative effects. Methods Twenty-nine PD patients admitted in our department from January 2016 to December 2018, who underwent bilateral STN-DBS surgery were re-examined with CT scanning on the head after bilateral electrodes were implanted during the operation. The results were merged with preoperative 3T-MRI images (with planned targets). The implanted electrodes were measured and calculated for error distance from the planned targets. Unified Parkinson's Disease Rating Scale Ⅲ (UPDRSⅢ) was used to evaluate the improvement of the symptoms before and in 6 months after operation. Pearson correlation analysis was used to study the correlation among age, gender, onset age and course of disease with improvement rate and deviation. Results Finally, 27 patients were enrolled, and 54 electrodes were implanted successfully. There were no significant differences in the age, gender, onset age and course of disease and the improvement rate and deviation among these patients (P>0.05). No obvious difference was seen in the mean deviation between the first implanted electrodes and second implanted electrodes (t=1.437, P>0.05). The symptoms of all patients were obviously improved. In 6 months after surgery, the average improvement rate of systemic symptoms was (78.10±10.25)% with drug on, and the average decrease of the equivalent dose of levodopa was 45.07%. The improvement rate was (83.15± 9.16)% for the first side, and (83.52±11.21)% for the second side. There was no significant difference in the improvement of limb symptoms between the 2 sides (P>0.05). Conclusion The accuracy of simultaneous implantation of bilateral electrodes in STN-DBS is not significantly different from that of the electrodes implanted sequentially, while still achieving good clinical outcomes.

To better understand the future evolution of Jiemayangzong Glacier (JMYZG), the headstream of the Yarlung Zangbo River, we simulated its future ice thickness evolution using a two-dimensional higher-order numerical flowline model. Due to the sparsity of in situ observational data, we used a combination of field observations and inversion models of velocity and ice thickness to initialize the model parameters. We validated the parametrizations of the calving scheme by comparing the modeled and observed glacier terminus retreats. To estimate the response of JMYZG to climate change, the ice flow model was forced with different climate scenarios. We found that the JMYZG will retreat under different climate scenarios. By 2100, the volume loss of JMYZG will be approximately 34%, 67% and 81% under SSP1-2.6, SSP3-7.0 and SSP5-8.5, respectively.

The smart pseudoscopic-to-orthoscopic conversion (SPOC) algorithm can synthesize a new elemental image array (EIA) using the already captured EIA, but the algorithm only relies on one simulated ray to establish the mapping relationship between the display pixels and the synthetic pixels. This paper improves the SPOC algorithm and proposes the average SPOC algorithm, which fully considers the converging effect of the synthetic lens on the ray. In the average SPOC algorithm, the simulated rays start from the synthetic pixel, pass through the upper and lower edges of the corresponding synthetic lens, and intersect the display lenses, respectively. Then, the value of the synthetic pixel is equivalent to the average value of display pixels, which correspond to the display lenses covered by the rays. Theoretical analysis points out that the average SPOC algorithm can effectively alleviate the matching error between the display pixels and the synthetic pixels, thereby improving the accuracy of the synthetic elemental image array (SEIA) and the reconstruction effect. According to the experimental results we get, the superiority of the average SPOC algorithm is verified.

Integral imaging is an emerging three-dimensional display technology. However, some inherent issues such as depth inversion has restricted its development. As such, this paper proposes a pixel fusion technique to generate elemental image arrays and overcome pseudoscopic problems occurring in sparse imaging environments. The similarity between the aimed displayed rays and the two adjacent captured rays of an object in a parallel light field was measured by the ratio of the spatial distance of the displayed and captured rays to the interval of the adjacent captured light. Displayed pixel values were acquired for the parallel captured rays. Corresponding pixel position errors were determined in sparse capture conditions and the method was further improved by using the position errors to identify the correct pixel, resulting in higher image quality. The proposed technique does not require manual adjustment of reference planes or other parameters, even at low capturing densities. This provides added convenience and may reduce capturing costs in actual scenes. Experiments using two bricks in virtual scenes under 9 × 9 to 137 × 137 capture cameras were conducted, and the quality of the generated elemental image array was compared with smart pseudoscopic-to-orthoscopic conversion (SPOC). The peak signal-to-noize ratio (PSNR) and structural similarity (SSIM) values showed the effectiveness of the proposed technique. The optical reconstruction results from both real and virtual scenes demonstrated improvements in vision of reconstructed three-dimensional scenes.

Superhydrophobic surfaces with excellent hydrophobic properties were prepared by chemical redox process. The surface wettability and morphology were characterized and analyzed by contact angle measurement and scanning electron microscopy(SEM). The contact angle of the superhydrophobic surface is as high as 163.31°, and the sliding angle is less than 5°. The effect of different reaction time on surface morphology and wettability was investigated, the performance of the static water droplets and the dynamic anti-icing performance of the superhydrophobic surface was explored by using a self-made icing testing system, and the experimental results were analyzed by combining the one dimensional heat transfer theory and classical nucleation theory. The results show that the surface hydrophobicity is the best when the reaction is 80min. The delay icing time of static water droplets on superhydrophobic surface is about 5 times than the normal sample, icing temperature is also low 3.3℃. There is no accumulated water and ice from start to end on superhydrophobic surface when water droplets impacting the cold surface. The as-prepared superhydrophobic surfaces show excellent static and dynamic anti-icing performance.

C19H13NO3, triclinic, P1̅ (no. 2), a = 9.4457(6) Å, b = 11.0520(7) Å, c = 14.6746(9) Å, α = 100.779(1)°, β = 102.738(1)°, γ = 93.065(1)°, V = 1460.68(16) Å3, Z = 4, Rgt(F) = 0.0410, wRref(F2) = 0.0911, T = 291 K.

BackgroundTokamak is a possible implementation of controlled nuclear fusion whilst the particle transportation plays an important role in maintaining the progress of nuclear fusion reactions.PurposeThis study aims to investigate the effects of ripple field and neoclassical tearing mode (NTM) on the migration of deuterium ions in Tokamak by numerical simulation. and provide a reference for the confinement of high energy particles.MethodsThe guiding center orbit code ORBIT was employed for numerical simulation. Effects of NTM and ripple field on particles with different positions, pitch angles and energies, were studied in details.Results & ConclusionsSimulation results show that the particle loss rate is high under the condition of high magnetic surface and low pitch angle. NTM mainly causes the loss of passing particles, while the loss of trapped particles is mainly caused by ripple field. When both perturbations are considered, the loss of particles is approximately the sum of losses by two perturbations acting alone. Ripple field will significantly increase toroidal angular momentum diffusion of trapped particles without affecting the passing particles, whilst NTM mainly influences toroidal angular momentum diffusion of passing particles. The particle loss situation basically keeps the original characteristics regardless of NTM frequency varition, while the momentum diffusion condition of particle loss changes with the increase of NTM frequency.

This exploratory qualitative case study investigates how graduate students in education experience, attribute, and combat academic boredom. Three areas of concern are addressed: (a) the contributing factors to boredom, (b) how attributional style (internal vs. external) relates to coping with boredom, and (c) the differences between combating class-related boredom and learning-related boredom. Results showed that the onset of boredom was mostly influenced by a lack of interest, lack of utility value, and autonomy frustration. This study extended the existing literature by discovering an interaction between students' attributional style and their coping strategies for boredom during classroom instruction. Specifically, students who argued that the instructor should hold more responsibility for boredom in class tended to take avoidance coping as their primary strategy (e.g., doodling). By comparison, students who opted to approach the problem positively (e.g., taking notes) are prone to attribute internally. Attribution does not appear to have a mediating effect on the relationship between experience of boredom and coping strategies for learning-related boredom. Implications for graduate and adult education and findings in the context of recent theoretical frameworks are discussed.

BackgroundGlucagon-like peptide-1 (GLP-1) has been reported to have beneficial impacts on improving human's metabolism and ameliorating insulin resistance. While insulin is another important and conventional drug in diabetes treatment, but it has an adverse effect on weight gain.PurposeTo make sure whether GLP-1 and insulin play different roles in human adipose-derived stem cells (hADSCs).MethodsWe examined the in vitro roles and molecular mechanisms of liraglutide, a GLP-1 analogue, and human insulin on hADSCs isolated from subcutaneous adipose tissue. Different concentrations (0, 0.1, 1, 10, 100nM) of liraglutide and insulin were added to proliferation and differentiation medium of hADSCs, respectively.ResultsLiraglutide inhibits while insulin promotes the proliferation and differentiation at the concentration of 100nM. Moreover, the levels of GSK-3 increase during differentiation and liraglutide could down-regulate it when compared with insulin. We also find that the activation of phosphorylated GSK-3α and GSK-3β is involved in the differentiation roles. And classical and non-classical Wnt pathways all play roles in the differentiation, which are characterized with the up/down-regulation of the expression of adipogenesis genes such as PPAR-γ and CEBP-α.ConclusionLiraglutide and insulin have contrary effects on the proliferation and adipogenesis via Wnt pathway in primary cultured ADSCs. Those effects could partly explain the different roles of GLP-1 and insulin on weight gain and insulin resistance.

Considering the storage increasing demand of 'multi-variety, small-batch' characteristic goods, we developed a new type of compact warehouse a three-dimensional double-ended compact storage system. Compared with the traditional three-dimensional automated storage and retrieval system (AS/RS) and existing three-dimensional compact AS/RS model, the storage system we designed exhibits excellent characteristics such as high density, high throughput efficiency, and more flexible configuration. There are three key points in our work listed as follows. Firstly, we establish the continuous travel time model under specific operating conditions in this new three-dimensional compact warehouse. Secondly, the three-dimensional size of the storage rack is optimised. The optimal three-dimensional proportion of the storage rack is obtained based on the model's optimal solution. Finally, numerical examples are given to analyse the influence of the I/O port layouts and related parameters on the system throughput efficiency. According to the optimisation results of the system model, a more reasonable rack dimension can be designed, which can provide an effective reference for the construction of a three-dimensional double-ended compact warehouse. [ABSTRACT FROM AUTHOR]