Research on the Assessment System of Computational Mechanics Courses Based on the TOPSIS Entropy Weight Model

This paper takes the assessment and evaluation of computational mechanics course as the background,and constructs a diversified course evaluation system that is student-centered and integrates both quantitative and qualitative evaluation methods.The system not only pays attention to students’practical operation and theoretical knowledge mastery but also puts special emphasis on the cultivation of students’innovative abilities.In order to realize a comprehensive and objective evaluation,the assessment and evaluation method of the entropy weight model combining TOPSIS(Technique for Order Preference by Similarity to Ideal Solution)multi-attribute decision analysis and entropy weight theory is adopted,and its validity and practicability are verified through example analysis.This method can not only comprehensively and objectively evaluate students’learning outcomes,but also provide a scientific decision-making basis for curriculum teaching reform.The implementation of this diversified course evaluation system can better reflect the comprehensive ability of students and promote the continuous improvement of teaching quality.

ODE CONVERSION TECHNIQUES AND THEIR APPLICATIONS IN COMPUTATIONAL MECHANICS

In this paper,a number of ordinary differential equation(ODE)conversion techniques for trans- formation of nonstandard ODE boundary value problems into standard forms are summarised,together with their applications to a variety of boundary value problems in computational solid mechanics,such as eigenvalue problem,geometrical and material nonlinear problem,elastic contact problem and optimal design problems through some simple and representative examples,The advantage of such approach is that various ODE bounda- ry value problems in computational mechanics can be solved effectively in a unified manner by invoking a stand- ard ODE solver.

Editorial: Computational mechanics of granular materials

Most of granular materials are highly heteroge- neous, composed of voids and particles with different sizes and shapes. Geological matter, soil and clay in nature, geo-structure, concrete, etc. are practical ex- amples among them. From the microscopic view, a lo- cal region in the medium is occupied by particles with small but finite sizes and granular material is naturally modeled as an assembly of discrete particles in contacts On the other hand, the local region is identified with a material point in the overall structure and this discon- tinuous medium can then be represented by an effective continuum on the macroscopic level

Deep Learning Applied to Computational Mechanics:A Comprehensive Review,State of the Art,and the Classics

Three recent breakthroughs due to AI in arts and science serve as motivation:An award winning digital image,protein folding,fast matrix multiplication.Many recent developments in artificial neural networks,particularly deep learning(DL),applied and relevant to computational mechanics(solid,fluids,finite-element technology)are reviewed in detail.Both hybrid and pure machine learning(ML)methods are discussed.Hybrid methods combine traditional PDE discretizations with ML methods either(1)to help model complex nonlinear constitutive relations,(2)to nonlinearly reduce the model order for efficient simulation(turbulence),or(3)to accelerate the simulation by predicting certain components in the traditional integration methods.Here,methods(1)and(2)relied on Long-Short-Term Memory(LSTM)architecture,with method(3)relying on convolutional neural networks.Pure ML methods to solve(nonlinear)PDEs are represented by Physics-Informed Neural network(PINN)methods,which could be combined with attention mechanism to address discontinuous solutions.Both LSTM and attention architectures,together with modern and generalized classic optimizers to include stochasticity for DL networks,are extensively reviewed.Kernel machines,including Gaussian processes,are provided to sufficient depth for more advanced works such as shallow networks with infinite width.Not only addressing experts,readers are assumed familiar with computational mechanics,but not with DL,whose concepts and applications are built up from the basics,aiming at bringing first-time learners quickly to the forefront of research.History and limitations of AI are recounted and discussed,with particular attention at pointing out misstatements or misconceptions of the classics,even in well-known references.Positioning and pointing control of a large-deformable beam is given as an example.

Extracellular vesicles in anti-tumor drug resistance: Mechanisms and therapeutic prospects

Drug resistance presents a significant challenge to achieving positive clinical outcomes in anti-tumor therapy.Prior research has illuminated reasons behind drug resistance,including increased drug efflux,alterations in drug targets,and abnormal activation of oncogenic pathways.However,there's a need for deeper investigation into the impact of drug-resistant cells on parental tumor cells and intricate crosstalk between tumor cells and the malignant tumor microenvironment(TME).Recent studies on extracellular vesicles(EVs)have provided valuable insights.EVs are membrane-bound particles secreted by all cells,mediating cell-to-cell communication.They contain functional cargoes like DNA,RNA,lipids,proteins,and metabolites from mother cells,delivered to other cells.Notably,EVs are increasingly recognized as regulators in the resistance to anti-cancer drugs.This review aims to summarize the mechanisms of EV-mediated anti-tumor drug resistance,covering therapeutic approaches like chemo-therapy,targeted therapy,immunotherapy and even radiotherapy.Detecting Ev-based biomarkers to predict drug resistance assists in bypassing anti-tumor drug resistance.Additionally,targeted inhibition of EV biogenesis and secretion emerges as a promising approach to counter drug resistance.We highlight the importance of conducting in-depth mechanistic research on EVs,their cargoes,and functional ap-proaches specifically focusing on EV subpopulations.These efforts will significantly advance the devel-opment of strategies to overcome drug resistance in anti-tumor therapy.

Research on the Library Enterprise Development Prospects and Challenges under the Environment of Big Data and Cloud Computing

In this paper, we conduct research on the library development prospects and challenges under the environment of big data and cloud computing. Increasingly nervous and public libraries are facing funding, resources construction pace slow or stagnant difficult situation, readers to the library cause in the new times challenge. Big data era has quietly come, for the knowledge storage, use and development as own duty, the library, how to improve the ability of handling large amounts of growth literature is urgent. Our methodology solves the issues well which will be meaningful.

Research Progress and Application Prospects of Mulching Technology

This article mainly covers the agricultural technology and traditional technology of plastic film mulching in China through the contrast and analysis. The mechanism and effect of plastic mulching technology is expounded, and the main use, positive role and development prospects of the technology in agricultural production, as well as the technology of agricultural soil conservation are introduced. In addition, existing problems and countermeasures are put forward to promote the development of agriculture in arid areas.

Mechanism, current status, and prospects of MSC and its extracellular vesicles in the treatment of IBD

The etiology of inflammatory bowel disease(IBD)is multifaceted,involving genetic susceptibility,immune dysregulation,alterations in the gut microbiota,and environmental factors.Both intrinsic and extrinsic factors can disrupt the intestinal mucosal barrier,leading to chronic nonspecific inflammation,local structural changes,and gastrointestinal dysfunction.Historically,due to a lack of effective treatments,recurrent inflammation and microcirculatory disturbances could result in complications such as intestinal fistulas,strictures,obstructions,perforations,gastrointestinal bleeding,sepsis,etc.,thereby increasing the risk of intestinal cell carcinoma and mortality.While the overall incidence of IBD remains at 0.5%in North America and Europe,its annual incidence is increasing in Asia,Africa,and South America,resulting in a growing number of patients and warning significant attention.Recent research has highlighted mesenchymal stem cell(MSC)therapy as an innovative treatment option for IBD due to its capacity to modulate inflammatory immune responses and promote tissue regeneration.A current preclinical study has shown a promising result,with systemic administration of MSCs in patients with reduced intestinal inflammation and no intestinal inflammation.In addition,in a new study,the use of mesenchymal stem cell-derived exosomes(MSC-EXOs)was successful,a type derived from mesenchymal stem cells,was successful,especially in patients with refractory anal fistula.Consequently,MSC therapy has become a preferred approach in IBD treatment,showcasing the potential application prospects for stem cell-based therapy in IBD.However,clinical research in this field still needs to refine strategies and further explore to lay a solid foundation.

Micro air vehicle-motivated computational biomechanics in bio-flights:aerodynamics,flight dynamics and maneuvering stability

Aiming at developing an effective tool to unveil key mechanisms in bio-flight as well as to provide guidelines for bio-inspired micro air vehicles（MAVs） design,we propose a comprehensive computational framework,which integrates aerodynamics,flight dynamics,vehicle stability and maneuverability.This framework consists of（1） a Navier-Stokes unsteady aerodynamic model;（2） a linear finite element model for structural dynamics;（3） a fluidstructure interaction（FSI） model for coupled flexible wing aerodynamics aeroelasticity;（4） a free-flying rigid body dynamic（RBD） model utilizing the Newtonian-Euler equations of 6DoF motion;and（5） flight simulator accounting for realistic wing-body morphology,flapping-wing and body kinematics,and a coupling model accounting for the nonlinear 6DoF flight dynamics and stability of insect flapping flight.Results are presented based on hovering aerodynamics with rigid and flexible wings of hawkmoth and fruitfly.The present approach can support systematic analyses of bio- and bio-inspired flight.

Computational Simulation of Aptamer-target Binding Mechanisms

Aptamers are a type of single-chain oligonucleotide that can combine with a specific target.Due to their simple preparation,easy modification,stable structure and reusability,aptamers have been widely applied as biochemical sensors for medicine,food safety and environmental monitoring.However,there is little research on aptamer-target binding mechanisms,which limits their application and development.Computational simulation has gained much attention for revealing aptamer-target binding mechanisms at the atomic level.This work summarizes the main simulation methods used in the mechanistic analysis of aptamer-target complexes,the characteristics of binding between aptamers and different targets(metal ions,small organic molecules,biomacromolecules,cells,bacteria and viruses),the types of aptamer-target interactions and the factors influencing their strength.It provides a reference for further use of simulations in understanding aptamer-target binding mechanisms.

Toward a Unified Mathematical and Computational Framework for Control and Mechanics

This is a brief review on the recent book: Duality System in Applied Mechanics and Optimal Control, by Zhong Wan-Xie, published by Kluwer Academic Publishers, 2004. The book represents a significant effort to re-establish the historic and deep tie between control and mechanics by striving to connect and integrate concepts, methods, and algorithms in mechanics and control so that a unified framework can be established for both analytical and computational purposes. Clearly, it has demonstrated that the duality system method can be used as a mathematical and systematic foundation to deal with many important concepts and problems in both mechanics and control. This book is not only very useful for research and applications, but also extremely helpful for multidisciplinary curriculum development when students from one field are trying to learning and applying concepts and methods from the other field.

导航辅助全膝关节置换应用功能学对线恢复患者固有生理力线和关节线倾角

背景:机械轴对线是全膝关节置换术中的“金标准”对线技术,但是无论假体材料和导航机器人辅助技术如何发展,应用机械轴对线的全膝关节置换后仍存在20%左右的患者不满意率。目的:探讨导航辅助全膝关节置换过程中应用功能学对线的早期疗效。方法:回顾性分析2019年10月至2023年6月连续44例(50膝)行计算机导航辅助全膝关节置换术中应用功能学对线的患者资料,男12例(14膝),女32例(36膝);选择同期同一手术团队行导航辅助全膝关节置换术中应用机械轴对线的46例(50膝)连续病例作为对照,男5例(5膝),女41例(45膝)。观察两组顾患者胫骨侧截骨角度、胫骨平台截骨量、股骨侧截骨角度、股骨远端、后方及前方截骨量、关节线移动情况;对比术前、术后屈曲和伸直间隙内外侧松弛度、髋-膝-踝角、股骨远端机械轴外侧角、胫骨近端机械轴内侧角、关节汇聚角、矢状面股骨组件角、胫骨后倾角、算术髋-膝-踝角、关节线倾角、膝关节冠状面力线分型、西安大略和麦克马斯特大学骨关节炎指数、美国特种外科医院评分及膝关节遗忘评分。结果与结论:①功能学对线组术中胫骨平台截骨角度大于机械轴对线组,间隙不平衡比例(2%)小于机械轴对线组(18%),差异均有显著性意义(P<0.05);②术后功能学对线组髋-膝-踝角、胫骨近端机械轴内侧角、算术髋-膝-踝角、关节线倾角小于机械轴对线组,差异均有显著性意义(P<0.05);③术前最常见的膝关节冠状面力线分型是Ⅰ型(功能学对线组80%,机械轴对线组42%);④术后功能学对线组关节线倾角<177°比例为44%,大于机械轴对线组的14%;⑤功能学对线组术后1,6个月及末次随访美国特种外科医院评分高于机械轴对线组,差异均有显著性意义(P<0.05);功能学对线组术后1个月西安大略和麦克马斯特大学骨关节炎指数低于机械轴对线组,差异有显著性意义(t=-2.85,P=0.005);两组术后膝关节活动度及膝关节遗忘评分相比差异均无显著性意义(P>0.05);⑥提示导航辅助全膝关节置换应用功能学对线能够优化早期临床疗效;与机械轴对线相比,功能学对线在恢复患者固有生理力线和关节线倾角、避免软组织松解方面更具优势。

改进YOLOv7的结直肠息肉检测算法

计算机辅助诊断对提高息肉诊断准确率和降低结直肠癌死亡率至关重要,但息肉形态各异,息肉类似物和肠内的复杂环境导致目前的方法存在较多的误诊和漏诊。因此提出了一种改进的YOLOv7结直肠息肉检测算法(YOLOv7-IDH),使用含隐式知识的高效解耦头,充分利用隐含信息并防止分类和回归任务之间相互干扰;引入全局注意力机制,增强模型对浅层特征的提取能力;对SPPCSPC模块进行优化,减少模型参数和提高收敛速度。实验结果表明,改进模型在组合数据集上的F1分数和mAP@0.5分别达到了94.8%和97.1%,可以满足息肉自动检测的要求。

非编码RNA与间充质干细胞研究的相关计量学分析

背景:非编码RNA作为一类不编码蛋白质的RNA分子,在细胞调控中发挥关键作用。同时,间充质干细胞具有多向分化潜能,对组织修复和再生至关重要。近年来,研究者们对非编码RNA在调控间充质干细胞功能中的作用展开了深入探讨。目的:通过文献计量学分析方法系统地了解非编码RNA与间充质干细胞相关研究的发展趋势与关键领域。方法:从Web of Science核心合集1990年至今的科学引文索引扩展获取非编码RNA与间充质干细胞相关研究的文献数据,运用VOSviewer和Cite Space计量学软件对年份、国家或地区、研究机构、被引文献和关键词进行发文量、聚类、被引频次、突增性和中介中心性进行分析,揭示该研究领域的知识基础及前沿热点。结果与结论:(1)最终纳入5348篇文献,发表在1997-2021年,相关文献呈现明显的增长趋势,尽管在2022年略有减少,其发文量仍保持较高水平,中国在该领域的研究中占据主导地位,其中上海交通大学为最活跃的机构。(2)对被引文献分析发现,高突增性、高中介中心性、高被引的文献主要与微小RNA、细胞外囊泡和骨代谢等内容相关,这些文献构成了非编码RNA与间充质干细胞研究领域的重要知识基础。(3)对关键词进行突增性分析发现,至今保持高突增性的关键词包括外泌体、环状RNA、细胞外囊泡和损伤。(4)对关键词进行聚类演变分析,发文量仍保持增长趋势的关键词聚类包括:肿瘤微环境、骨关节炎、氧化应激和细胞外囊泡,这些关键词反映了目前以及未来该领域的研究热点。(5)文章结果不仅展示了非编码RNA与间充质干细胞研究领域的研究态势,更重要的是有望为研究人员提供潜在的方向和启示。

基于双流特征融合的肺结节图像分割网络

为了提高对肺结节的准确分割,文中提出一种CSF-UNet的双骨干网络特征提取方法。使用两种不同侧重的骨干网络并行提取图像特征,通过利用ConvNeXt网络提取局部特征,并结合Swin Transformer网络提取全局特征来提升模型的特征提取能力。提出了一种自适应大核融合模块,有效地融合两种不同规格的特征,通过串联两个大核卷积获得更大的感受野和动态选择机制来突出重要的空间区域。在SPPF中融合了ECA通道注意力和密集链接,提出了ESPP模块以进一步挖掘双骨干网络提取的高级语义信息,使网络更加关注重要的特征通道。在LIDC数据集上的实验结果表明,提出的模型在3个指标上优于基本UNet模型以及最近几年其他研究团队提出的针对该数据集的分割网络。最终,CSF-UNet模型实现了78.1%的IoU、87.71%的DSC、87.19%的敏感度和88.23%的精确度。这些结果表明,该模型在肺结节分割方面表现出良好的性能,对医生进行早期肺结节诊断具有重要的临床意义和应用价值。

口腔种植修复中钛基底氧化锆基台的制作和力学性能

背景:随着计算机辅助设计和计算机辅助制造技术的发展,钛基底氧化锆基台因具备良好的应用优势被广泛运用于临床,但仍存在一些问题,尚缺乏共识性的设计标准。目的:综述钛基底氧化锆基台的制作方法及基台连接、穿龈设计、基台角度和粘接对钛基底氧化锆基台各类力学性能的影响。方法:检索Pub Med数据库和中国知网2010-2023年发表的相关文献,检索词为“zirconia abutment,titanium base;氧化锆基台,钛基底”,部分经典文献延长检索时间限制,通过纳入和排除标准获取相关文献,对57篇符合标准的文献进行综述。结果与结论:建议临床医生尽量选择具有抗旋结构的基台连接或是具有莫氏锥度的非抗旋连接,当运用钛基底氧化锆基台时,种植体应放置在正确的轴向角度(植体轴向向唇侧倾斜角度不超过15°或略向腭侧倾斜);当植体轴向向唇侧倾斜角度≥30°时,应当适当降低咬合力,以降低种植体、基台及修复体机械并发症和生物并发症的风险;应尽可能选择穿龈高度较高的钛基底,并且其穿龈角度不应超过40°。Multilink Hybrid Abutment可以作为氧化锆基台与钛基底口外粘结的首选粘接剂。

Progress and prospects of acupuncture research on the mechanism of post-stroke depression

The articles on the pathogenesis of post-stroke depression(PSD)and the acupuncture treatment mechanism of PSD from January 2010 through to June 2020 were retrieved from China National knowledge Infrastructure(CNKI),Wanfang Database,VIP China Science-Technology and National Social Sciences Database.In summary,the potential mechanism of acupuncture in treatment of PSD is explained from the following three aspects:acupuncture regulating monoamine neurotransmitters,acupuncture regulating neurotrophic factors and acupuncture regulating cytokines.The limitation and prospects of the current researches are also put forward so as to provide the references and to determine the research direction in the future.

A Computational Fluid Dynamics (CFD) Analysis of an Undulatory Mechanical Fin Driven by Shape Memory Alloy

Many fishes use undulatory fin to propel themselves in the underwater environment. These locomotor mechanisms have a popular interest to many researchers. In the present study, we perform a three-dimensional unsteady computation of an undulatory mechanical fin that is driven by Shape Memory Alloy （SMA）. The objective of the computation is to investigate the fluid dynamics of force production associated with the undulatory mechanical fin. An unstructured, grid-based, unsteady Navier-Stokes solver with automatic adaptive remeshing is used to compute the unsteady flow around the fin through five complete cycles. The pressure distribution on fin surface is computed and integrated to provide fin forces which are decomposed into lift and thrust. The velocity field is also computed throughout the swimming cycle. Finally, a comparison is conducted to reveal the dynamics of force generation according to the kinematic parameters of the undulatory fin （amplitude, frequency and wavelength）.

(3+1)-Dimensional Quantum Mechanics from Monte Carlo Hamiltonian: Harmonic Oscillator

In Lagrangian formulation, it is extremely difficult to compute the excited spectrum and wavefunctions ora quantum theory via Monte Carlo methods. Recently, we developed a Monte Carlo Hamiltonian method for investigating this hard problem and tested the algorithm in quantum-mechanical systems in 1+1 and 2t1 dimensions. In this paper we apply it to the study of thelow-energy quantum physics of the (3+1)-dimensional harmonic oscillator.

High entropy materials based electrocatalysts for water splitting:Synthesis strategies,catalytic mechanisms,and prospects

Among various electrocatalysts,high entropy materials(HEMs)have attracted great attention due to the distinctive designing concept and unique properties with captivating electrocatalytic activity and stability.To date,HEMs have been a new family of advanced electrocatalysts in the research field of water electrolysis.In this work,the structural features and synthesis strategies of high entropy catalysts are reviewed,especially,their performances for catalyzing hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)in water electrolysis are presented,in which the crucial roles of structure,composition,multisites synergy,and“four core effects”for enhancing catalytic activity,stability,and resistance of electrochemical corrosion are introduced.Besides,the design tactics,main challenges,and future prospects of HEM-based electrocatalysts for HER and OER are discussed.It is expected to provide valuable information for the development of low-cost efficient HEM-based electrocatalysts in the field of water electrolysis.