检索结果-内蒙古大学图书馆

Biomechanical Analysis of Odontoid and Transverse Atlantal Ligament in Humans with Ponticulus Posticus Variation Under Different Loading Conditions: Finite Element Study

SSRN

引用

SSRN 2022年

作者： Güvercin, Yılmaz Yaylacı, Murat Dizdar, Ayberk Kanat, Ayhan Yaylacı, Ecren Uzun Ay, Sevil Abdioğlu, Ahmet Atilla Şen, Ahmet Trabzon Kanuni Training and Research Hospital Department of Orthopaed & Traumatol Trabzon61000 Turkey Recep Tayyip Erdogan University Biomedical Engineering MSc Program Rize53100 Turkey Recep Tayyip Erdogan University Department of Civil Engineering Rize53100 Turkey Kocaeli University Department of Biomedical Engineering Kocaeli41380 Turkey Recep Tayyip Erdogan University Department of Neurosurgery Rize53100 Turkey Karadeniz Technical University Surmene Faculty of Marine Science Trabzon61530 Turkey Department of Civil Engineering Artvin Coruh University Artvin08100 Turkey Fatih State Hospital Orthopaed & Traumatol Trabzon61100 Turkey University of Health Sciences Trabzon Kanuni Training and Research Hospital Anesthesiaa and Reanimation Department Trabzon61100 Turkey

Purpose: Ponticulus posticus (PP) is a variation of the bone bridge that appears in the first cervical vertebra and through which the vertebral artery passes. Odontoid fractures are common spinal bone fractures in older people. This study aims to investigate the effect of neck movements on the odontoid and transverse atlantal ligament (TAL) of people with PP variation from a biomechanical ***: C1, C2, and C3 vertebrae of the occipital bone were analyzed using the finite element method (FEM). In this study, solid models were created with the help of normal (N), incomplete (IC), and asymmetric complete (AC) PP tomography images. The necessary elements for the models were assigned, and the material properties were defined for the elements. As boundary conditions, models were fixed from the C3 vertebra, and 74 N loading was applied from the occipital bone. Stress and deformation values in the odontoid and transverse atlantal ligament were obtained by applying 1.8 Nm moment in flexion, extension, bending, and axial rotation ***: As a result of this study, the stress and deformation values of all three models in odontoid and TAL were obtained, and numerical results were evaluated. In all models, stress and deformation values were obtained in decreasing order in rotation, bending, extension, and flexion movements. The highest stress and strain values were obtained in AC and the lowest in N. In all movements of the three models, the stress and deformation values obtained in the TAL are lower than in ***: The greatest stresses and deformations obtained in spines (AC) with PP were found in the odontoid. This may help explain the pathogenesis of odontoid fractures in older people. First, this study explains the mechanism of formation of neck trauma in people with PP and the need for a more careful evaluation of the direction of arrival. Secondly, the study shows that the rotational motion of the neck independent of PP has more negative ef

关键词： Finite element method

来源：评论

学校读者我要写书评

暂无评论

Effect of Thai Silk Fibroin on Mechanical Properties of Bioactive Glass Silk Fibroin Hybrid Bone Scaffolds

引用

IOP Conference Series: Materials Science and engineering 2021年第1期1163卷

作者： Ayuth Vejpongsa Peerapat Thongnuek Biomaterial Engineering for Medical and Health Research Unit Faculty of Engineering Chulalongkorn University Pathum Wan 10330 Thailand Interdisciplinary Program of Biomedical Engineering Faculty of Engineering Chulalongkorn University Pathum Wan 10330 Thailand

Bioactive glass (70 mol% Si and 30% Ca; 70S30C) has been used as tissue engineering scaffolds in various research despite its brittleness due to its easy-to-replicate formula, extensive interconnected pores and natural bone bonding property of bioactive glass (BG). Thai silk fibroin (SF) is natural polymer with many desirable properties; biocompatibility, mechanical strength, biodegradability. Using BG-SF hybrid scaffolds could employ the positive effects of both bioactive glass and silk fibroin. Serving as bone scaffolds, BG-SF scaffolds must resist compression and other types of mechanical load depending on the application. This study fabricates scaffolds with various ratios of BG:SF (BG:SF; 90:10, 80:20 with 100:0 as control), and their stress-strain profiles were investigated. As expected, the scaffolds with highest BG content exhibited the curve resembling that of porous foam while the elastomeric stress-strain profile was becoming more evident when the SF content was increased. This study hence demonstrated fine-tuning mechanical properties of the BG using locally enriched SF.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Changes in teacher self-efficacy through engagement in an engineering professional development partnership (RTP)

Changes in teacher self-efficacy through engagement in an en...

引用

2020 ASEE Virtual Annual Conference, ASEE 2020

作者： Schilling, Malle R. Paradise, Tawni Grohs, Jacob R. Matusovich, Holly M. Carrico, Cheryl Lesko, Holly Larson Kirk, Gary R. Virginia Tech United States Virginia Tech Department of Engineering Education United States Faculty Status in Biomedical Engineering and Mechanics and the Learning Sciences and Technologies Virginia Polytechnic Institute State University United States Department of Engineering Education Virginia Polytechnic Institute State University United States Cheryl Carrico Consulting LLC Program Virginia Tech United States Dickinson College United States

K-12 teachers serve a critical role in their students' development of interest in engineering, especially as engineering content is emphasized in curriculum standards. However, teachers may not be comfortable teaching engineering in their classrooms as it can require a different set of skills from which they are trained. Professional development activities focused on engineering content can help teachers feel more comfortable teaching the subject in their classrooms and can increase their knowledge of engineering and thus their engineering teaching self-efficacy. There are many different types of professional development activities teachers might experience, each one with a set of established best practices. VT PEERS (Virginia Tech Partnering with Educators and Engineers in Rural Communities) is a program designed to provide recurrent hands-on engineering activities to middle school students in or near rural Appalachia. The project partners middle school teachers, university affiliates, and local industry partners throughout the state region to develop and implement engineering activities that align with state defined standards of learning (SOLs). Throughout this partnership, teachers co-facilitate engineering activities in their classrooms throughout the year with the other partners, and teachers have the opportunity to participate in a two-day collaborative workshop every year. VT PEERS held a workshop during the summer of 2019, after the second year of the partnership, to discuss the successes and challenges experienced throughout the program. Three focus groups, one for each grade level involved (grades 6-8), were held during the summit for teachers and industry partners to discuss their experiences. None of the teachers involved in the partnership have formal training in engineering. The transcripts of these focus groups were the focus of the exploratory qualitative data analyses to answer the following research question: How do middle-school teachers develop t

关键词： Curricula

来源：评论

学校读者我要写书评

暂无评论

Improving the corrosion, biocompatibility and antibacterial properties of pure magnesium implants through silver-doped calcium phosphate coatings

引用

Colloids and Surfaces A: Physicochemical and engineering Aspects 2025年 724卷

作者： Farasat Iqbal Hira Fatima Asif Ali Sohail Nadeem Kinza Mujahid Interdisciplinary Research Centre in Biomedical Materials COMSATS University Islamabad Lahore Campus Pakistan Department of Chemistry University of Management and Technology Lahore Pakistan Research Unit Plasma Technology (RUPT) Department of Applied Physics Faculty of Engineering and Architecture Ghent University Belgium

Magnesium-based implants are remarkably noticed as biomedical implants due to exceptional characteristics such as biodegradability, bio-compatibility, and mechanical properties close to human bone. Pure magnesium substrate is preferred over other magnesium-based alloys because it does not contain rare earth metals and release no toxic ions in body. However, the fast corrosion rate of magnesium-based implants and post-surgical infection are considered crucial challenges in biomedical applications. To address these critical challenges, silver was incorporated into a calcium phosphate coating on a pure magnesium substrate via hydrothermal synthesis at pH values of 4 and 7 in this investigation. This silver-doped calcium phosphate coating improved the fast corrosion rate with bacterial inhibition and osteogenic differentiation. A uniform, dense coating morphology is observed through scanning electron microscopy and elemental distribution on the whole surface was analysed for Energy dispersive scanning. The corrosion behavior of samples were investigated though electrochemical testing. The crystalline and deposited phases were investigated through X-ray diffraction and information regarding functional groups was observed through FTIR technique. The coating adhesion test was used to check the coating's mechanical strength. It is observed that the coating has homogenized surface morphology, and crystalline phase nature with desired elemental composition and these factors improved its mechanical strength and 98 % corrosion resistance than un-coated substrate. Moreover, such a coating not only improved the antibacterial efficacy and corrosion resistance but also enhanced the cell proliferation and bone differentiation rate of the osteoblast MC3TC cell line with appropriate silver concentration.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Synthesis of Gadolinium-Doped Molybdenum Diselenide Nanospheres for Ultrasensitive Electrochemical Determination of Essential Amino Acid in Human Serum and Milk Samples

引用

Journal of the Electrochemical Society 2023年第5期170卷 057501-057501页

作者： Jeromiyas, Nithiya Govindasamy, Mani Alothman, Asma A. Ouladsmane, Mohamed Huang, Chi-Hsien National Kaohsiung University of science and Technology Kaohsiung City81157 Taiwan Department of Chemistry Korea University Seongbuk-gu Seoul Korea Republic of Faculty International PhD Program in Innovative Technology of Biomedical Engineering and Medical Devices Ming Chi University of Technology New Taipei City243303 Taiwan Department of Research and Innovation Saveetha School of Engineering SIMATS Thandalam Chennai602105 India Chemistry Department College of Science King Saud University Riyadh11451 Saudi Arabia Department of Materials Engineering Ming Chi University of Technology New Taipei City243303 Taiwan Biochemical Technology R&D Center Ming Chi University of Technology New Taipei City243303 Taiwan

The electrocatalytic activity and electronic conductivity of 2D transition metal chalcogenides are usually enhanced by as follows the ideal strategy such as doping or substitution heterogeneous atoms. Here, a rare Earth metal ion of gadolinium (Gd3+) was doped with MoSe2 and synthesized through the hydrothermal method. The morphology and nanostructure of Gd3+ with MoSe2 spheres were analyzed under X-ray diffraction, Fourier-transform infrared spectroscopy, X-ray photoelectron, High-resolution transmission electron microscopy analysis, Field emission scanning electron microscopy, and energy-dispersive spectroscopy. Furthermore, the Gd3+ doped MoSe2 sphere modified glassy carbon electrode (Gd@MoSe2/GCE) was used for the sensing of tryptophan. The Gd@MoSe2 modified GCE shows remarkable sensing performance of tryptophan resulting in a linear range (20 nM-220 μM) with a low detection limit (6.7 nM). Under the optimal condition, the developed electrochemical sensor was successfully used to determine tryptophan (TRP) in blood serum and milk samples. The electrochemical biosensing results suggest that the doping of the Gd3+ doped MoSe2 sensor is a promising electrocatalyst in biological and food samples. © 2023 The Electrochemical Society ("ECS"). Published on behalf of ECS by IOP Publishing Limited.

关键词： Amino acids

来源：评论

学校读者我要写书评

暂无评论

From sleep medicine to medicine during sleep : A clinical perspective

arXiv

引用

arXiv 2021年

作者： Bar, Nitai Sobel, Jonathan A. Penzel, Thomas Shamay, Yosi Behar, Joachim A. Rambam Hospital Haifa Israel Biomedical Engineering Faculty Technion-Israel Institute of Technology Haifa Israel Interdisciplinary Center of Sleep Medicine Charite University Medicine Berlin Chariteplatz 1 Berlin10117 Germany Saratov State University Saratov Russia

Sleep has a profound influence on the physiology of body systems and biological processes. Molecular studies have shown circadian-regulated shifts in protein expression patterns across human tissues, further emphasizing the unique functional, behavioral and pharmacokinetic landscape of sleep. Thus, many pathological processes are also expected to exhibit sleep-specific manifestations. Nevertheless, sleep is seldom utilized for the study, detection and treatment of non-sleep-specific pathologies. Modern advances in biosensor technologies have enabled remote, non-invasive recording of a growing number of physiologic parameters and biomarkers. Sleep is an ideal time frame for the collection of long and clean physiological time series data which can then be analyzed using data-driven algorithms such as deep learning. In this perspective paper, we aim to highlight the potential of sleep as an auspicious time for diagnosis, management and therapy of non-sleep-specific pathologies. We introduce key clinical studies in selected medical fields, which leveraged novel technologies and the advantageous period of sleep to diagnose, monitor and treat pathologies. We then discuss possible opportunities to further harness this new paradigm and modern technologies to explore human health and disease during sleep and to advance the development of novel clinical applications – from sleep medicine to medicine during sleep. Copyright © 2021, The Authors. All rights reserved.

关键词： Sleep research

来源：评论

学校读者我要写书评

暂无评论

In vivo investigation of 3D printed polycaprolactone/graphene electro-active bone scaffolds

引用

Bioprinting 2021年 24卷

作者： Lopes Nalesso, Paulo Roberto Wang, Weiguang Hou, Yanhao Bagne, Leonardo Pereira, Amanda Tavares Helaehil, Julia Venturini Moretti de Andrade, Thiago Antônio Chiarotto, Gabriela Bortolança Bártolo, Paulo Caetano, Guilherme Ferreira Graduate Program in Biomedical Sciences University Centre of Herminio Ometto Foundation Sao Paulo Araras 13607-339 Brazil Department of Mechanical Aerospace and Civil Engineering School of Engineering Faculty of Science and Engineering The University of Manchester Manchester M13 9PL United Kingdom

Additive manufactured scaffolds are widely used as 3D support structures for tissue engineering. This paper investigates the mechanisms behind bone regeneration due to the combined use of 3D printed poly (ϵ-caprolactone)/graphene (PCL/G) electro-active scaffolds and electrical stimulation. A comprehensive in vivo study was conducted to assess the proposed approach, using a rat model. Results show that the combined use of electro-active scaffolds and electrical stimulation therapy accelerates the bone regeneration process and the formation of more organized new bone, through fast angiogenesis, and a rapid transition to the mineralization and bone remodelling phase. The mechanism is investigated and explained. © 2021

关键词： Additive manufacturing Electrical stimulation Electro-active scaffolds Graphene In vivo bone Regeneration Poly(ϵ-caprolactone) Tissue engineering

来源：评论

学校读者我要写书评

暂无评论

BPS2025 - Analyzing the biophysical properties of pulmonary surfactant during bacterial infection using multiscale computational models

引用

Biophysical Journal 2025年第3期124卷 635a-636a页

作者： Jonathan R. Fritz Ian D. Bentley Joshua A. Englert Samir N. Ghadiali Interdisciplinary Biophysics Program Ohio State University Columbus OH USA Division of Pulmonary and Critical Care Medicine Department of Internal Medicine Ohio State Wexner Medical Center Columbus OH USA Department of Biomedical Engineering Ohio State University Columbus OH USA

来源：评论

学校读者我要写书评

暂无评论

Theoretical identification of thermostabilizing amino acid mutations for G-protein-coupled receptors

引用

Biophysical Reviews 2020年第2期12卷 323-332页

作者： Murata, Takeshi Yasuda, Satoshi Hayashi, Tomohiko Kinoshita, Masahiro Graduate School of Science Chiba University 1-33 Yayoi-cho Inage Chiba 263-8522 Japan Molecular Chirality Research Center Chiba University 1-33 Yayoi-cho Inage Chiba 263-8522 Japan Institute of Advanced Energy Kyoto University Uji Kyoto 611-0011 Japan Present address: Interdisciplinary Program of Biomedical Engineering Assistive Technology and Art and Sports Sciences Faculty of Engineering Niigata University 8050 Ikarashi 2-no-cho Nishi-ku Niigata 950-2181 Japan

Thermostabilization of a membrane proteins, especially G-protein-coupled receptors (GPCRs), is often necessary for biochemical applications and pharmaceutical studies involving structure-based drug design. Here we review our theoretical, physics-based method for identifying thermostabilizing amino acid mutations. Its novel aspects are the following: The entropic effect originating from the translational displacement of hydrocarbon groups within the lipid bilayer is treated as a pivotal factor;a reliable measure of thermostability is introduced and a mutation which enlarges the measure to a significant extent is chosen;and all the possible mutations can be examined with moderate computational effort. It was shown that mutating the residue at a position of N_BW = 3.39 (N_BW is the Ballesteros-Weinstein number) to Arg or Lys leads to the stabilization of significantly many different GPCRs of class A in the inactive state. Up to now, we have been successful in stabilizing several GPCRs and newly solving three-dimensional structures for the muscarinic acetylcholine receptor 2 (M2R), prostaglandin E receptor 4 (EP4), and serotonin 2A receptor (5-HT_2AR) using X-ray crystallography. The subjects to be pursued in future studies are also discussed. © 2020, International Union for Pure and Applied Biophysics (IUPAB) and Springer-Verlag GmbH Germany, part of Springer Nature.

关键词： G-protein-coupled receptor Integral equation theory Lipid bilayer Membrane protein Morphometric approach Protein folding Solvation thermodynamics Thermostabilizing mutation

来源：评论

学校读者我要写书评

暂无评论

Composite B-Spline Regularized Delta Functions for the Immersed Boundary Method: Divergence-Free Interpolation and Gradient-Preserving Force Spreading

arXiv

引用

arXiv 2024年

作者： Gruninger, Cole Griffith, Boyce E. Department of Mathematics University North Carolina Chapel HillNC United States Department of Applied Physical Sciences University of North Carolina Chapel HillNC United States Department of Biomedical Engineering University of North Carolina Chapel HillNC United States Carolina Center for Interdisciplinary Applied Mathematics University of North Carolina Chapel HillNC United States Computational Medicine Program University of North Carolina School of Medicine Chapel HillNC United States McAllister Heart Institute University of North Carolina School of Medicine Chapel HillNC United States

This paper presents an approach to enhance volume conservation in the immersed boundary (IB) method by employing regularized delta functions derived from composite B-splines. These delta functions are constructed using tensor product kernels, similar to the conventional IB method. However, the kernels are B-splines whose polynomial degree varies according to the normal and tangential directions of each velocity component. The conventional IB method, while effective for fluid-structure interaction applications, has long been challenged by poor volume conservation, particularly evident in simulations of pressurized, closed membranes. We demonstrate that composite B-spline regularized delta functions significantly enhance volume conservation through two complementary properties: they provide continuously divergence-free velocity interpolants and maintain the gradient character of forces corresponding to mean pressure jumps across interfaces. By correctly representing these forces as discrete gradients, they eliminate a key source of spurious flows that typically plague immersed boundary computations. Our approach maintains the local nature of the classical IB method, avoiding the computational overhead associated with the non-local Divergence-Free Immersed Boundary (DFIB) method’s construction of an explicit velocity potential which requires additional Poisson solves for interpolation and force spreading operations. Through a series of numerical experiments, we show that sufficiently regular composite B-spline kernels can maintain initial volumes to within machine precision. We provide a detailed analysis of the relationship between kernel regularity and the accuracy of force spreading and velocity interpolation operations. Our findings indicate that composite B-splines of at least C1 regularity produce results comparable to the DFIB method in dynamic simulations, with errors in volume conservation primarily dominated by truncation error of the employed time-stepping s

关键词： Delta functions

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：