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Modelling ballistic impact on military helmets:The relevance of projectile plasticity

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Defence Technology（防务技术） 2021年第5期17卷 1699-1711页

作者： A.caçoilo r.Mourao f.Teixeira-Dias A.Azevedo f.coghe r.A.f.Valente School of Engineering The University of EdinburghEdinburghEH93FGUK Dept.Weapon Systems and ballistics Royal Military AcademyBrusselsBelgium centre for Mechanical Technology and Automation Department of Mechanical EngineeringUniversity of AveiroPortugal

The need to develop armour systems to protect against attacks from various sources is increasingly a matter of personal,social and national *** develop innovative armour systems it is necessary to monitor developments being made on the type,technology and performance of the threats(weapons,projectiles,explosives,etc.) Specifically,the use of high protection level helmets on the battlefield is *** development of evaluation methods that can predict injuries and trauma is therefore of major ***,the risk of injuries or trauma that can arise from induced accelerations is an additional *** develop new materials and layouts for helmets it is necessary to study the effects caused by ballistic impacts in the human head on various *** use of numerical simulation is a fundamental tool in this *** work here presented focuses on the use of numerical simulation(finite elements analysis) to predict the consequences of bullet impacts on military helmets on human *** main objectives are to assess the level and probability of head trauma using the Head Injury criterion,caused by the impact of a 9 mm NATO projectile on a PASGT helmet and to quantify the relevance of projectile plasticity on the whole modelling *** accelerations derived from the impact phenomenon and the deformations caused on the helmet are evaluated using fully three-dimensional models of the helmet,head,neck and *** studies are done at impact angles ranging from 0 to 75°.results are presented and discussed in terms of HIc and probability of acceleration induced trauma *** comparison analyses are done using a rigid and a deformable projectile and it is observed that plastic deformation of the projectile is a significant energy dissipation mechanism in the whole impact process.

关键词： ballistic impact Helmet impact Plasticity finite element analysis Injury Trauma HIc

MODELING AND EXPErIMENTAL rESEArcH Of fOUr-STrAND LOW-frEQUENcY ELEcTrOMAGNETIc cASTING ALUMINUM ALLOY

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Acta Metallurgica Sinica(English Letters) 2007年第3期20卷 157-166页

作者： J.c. Li b.f. Wang J.Z. cui School of Materials ＆ Metallurgy Inner Mongolia University of Science and Technology Baotou 014010 China The Key Laboratory of Electromagnetic Processing of Materials Ministry of Education Northeastern University Shenyang 110004 China

With the aid of ANSYS software, the effect of different mould external part materials on magnetic flux density in the aluminum melt and magnetic field interaction of four coils applied with same currents were investigated. calculating results showed that magnetic flux density in the aluminum melt was greatly improved and the magnetic field interaction among different coils was decreased when external part of mould is made of soft magnetic material. based on the finding, a four-strand low-frequency electromagnetic casting 6063 aluminum alloy experiment was carried out in the laboratory . The experiment showed that the surface of the billet was smooth and had no exudations and cold shuts, the as-cast microstructures were fine, uniform, equiaxed, net-globular or globular under low-frequency electromagnetic field. The microstructure becomes finer with increased current value.

关键词： low-frequency electromagnetic casting finite element method aluminum alloy mould

A spotlight on dosage and subject selection for effective neuroprotection: exploring the central role of mitochondria

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Neural regeneration research 2025年第4期20卷 1081-1082页

作者： John Mitrofanis Jonathan Stone Michael r.Hamblin Pierre Magistretti Alim-Louis benabid Glen Jeffery fonds clinatec UniversitéGrenoble AlpesGrenobleFrance School of Medical Science University of SydneySydneyAustralia faculty of Health Sciences University of JohannesburgJohannesburgSouth Africa King Abdullah University of Science and Technology ThuwalSaudi Arabia Institute of Ophthalmology University College LondonLondonUK

Neurons are notoriously vulnerable cell *** the slightest change in their internal and/or external environments will cause much distress and dysfunction,leading often to their death.A range of pathological conditions,including stroke,head trauma,and neurodegenerative disease,can generate stress in neurons,affecting their survival and proper *** most neural pathologies,mitochondria become dysfunctional and this plays a pivotal role in the process of cell *** challenge over the last few decades has been to develop effective interventions that improve neuronal homeostasis under pathological *** interventions,often referred to as disease-modifying or neuroprotective,have,however,proved frustratingly elusive,at both preclinical and,in particular,clinical *** this perspective,we highlight two factors that we feel are key to the development of effective neuroprotective *** are:firstly,the choice of dose of intervention and method of application,and secondly,the selection of subjects,whether they be patients or the animal model.

关键词： protective dosage distress

Deep learning identification of novel autophagic protein-protein interactions and experimental validation of beclin 2-Ubiquilin 1 axis in triple-negative breast cancer

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Oncology research 2025年第1期33卷 67-81页

作者： Xiang Li Wenke Jin Lifeng Wu Huan Wang Xin Xie Wei Huang b O Liu State Key Laboratory of Southwestern chinese Medicine resources School of Pharmacy and College of Medical Technology Chengdu University of Traditional Chinese Medicine Chengdu 611137 China. Department of biotherapy Cancer Center and State Key Laboratory of Biotherapy West China Hospital Sichuan University Chengdu 610041 China.

background:Triple-negative breast cancer (TNbc), characterized by its lack of traditional hormone receptors and HEr2, presents a significant challenge in oncology due to its poor response to conventional therapies. Autophagy is an important process for maintaining cellular homeostasis, and there are currently autophagy biomarkers that play an effective role in the clinical treatment of tumors. In contrast to targeting protein activity, intervention with protein-protein interaction (PPI) can avoid unrelated crosstalk and regulate the autophagy process with minimal interference pathways.Methods:Here, we employed Naive bayes, Decision Tree, and k-Nearest Neighbors to elucidate the complex PPI network associated with autophagy in TNbc, aiming to uncover novel therapeutic targets. Meanwhile, the candidate proteins interacting with beclin 2 were initially screened in MDA-Mb-231 cells using beclin 2 as bait protein by immunoprecipitation-mass spectrometry assay, and the interaction relationship was verified by molecular docking and cO-IP experiments after intersection. colony formation, cellular immunofluorescence, cell scratch and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) tests were used to predict the clinical therapeutic effects of manipulating candidate PPI.results:by developing three PPI classification models and analyzing over 13,000 datasets, we identified 3733 previously unknown autophagy-related PPIs. Our network analysis revealed the central role of beclin 2 in autophagy regulation, uncovering its interactions with 39 newly identified proteins. Notably, the cO-IP studies identified the substantial interaction between beclin 2 and Ubiquilin 1, which was anticipated by our model and discovered in immunoprecipitation-mass spectrometry assay results. Subsequently, investigations showed that overexpressing beclin 2 increased Ubiquilin 1, promoted autophagy-dependent cell death, and inhibited proliferation and metastasis in MDA-Mb-231 cells.

关键词： Artificial intelligence (AI) Autophagy beclin 2 Protein-protein interactions (PPI) Triple-negative breast cancer (TNbc) Ubiquilin 1

Gene therapy for spinal muscular atrophy:perspectives on the possibility of optimizing SMN1 delivery to correct all neurological and systemic perturbations

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Neural regeneration research 2025年第7期20卷 2011-2012页

作者： Sharon J.brown rafael J.Yáñez-Muñoz Heidi r.fuller School of Pharmacy and bioengineering Keele UniversityKeeleUK Wolfson center for Inherited Neuromuscular Disease TORCH BuildingRJAH Orthopaedic HospitalOswestryUK *** Center of Gene and Cell TherapyDepartment of Biological SciencesSchool of Life Sciences and the EnvironmentRoyal Holloway University of LondonEghamUK

Spinal muscular atrophy(SMA)is a genetic condition that results in selective lower motor neuron loss with concomitant muscle weakness and *** genetic cause of SMA was understood in 1995 when loss or impairment of the survival motor neuron 1(SMN1)gene was identified as the main contributing factor(Lefebvre et al.,1995).This,in combination with the discovery that humans have a“back-up”gene,SMN2,which can produce low levels(approximately 10%)of the full-length functional SMN protein,has led to the generation of SMA-specific gene *** was traditionally classified according to age of symptom onset and developmental milestones achieved,with life expectancy and severity varying between ***,SMN2 copy number is used as a proxy for the prediction of disease severity,with higher SMN2 copy number typically being associated with reduced severity of SMA,although this relationship is not absolute:some individuals with low SMN2 copy number have less severe SMA phenotypes and vice ***,the etiology of SMA is further complicated by other factors,such as non-typical nucleotide variants and SMN2-independent modifiers of disease severity.

关键词： atrophy traditionally absolute

A comprehensive study for mass attenuation coefficients of different parts of the human body through Monte carlo methods

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Nuclear Science and Techniques 2016年第3期27卷 31-39页

作者： E.E.Ermis f.b.Pilicer E.Pilicer c.celiktas Physics Department Faculty of ScienceEge University Physics Department Faculty of Arts and ScienceUludag University

The gamma-ray mass attenuation coefficients of blood,bone,lung,eye lens,adipose,tissue,muscle,brain and skin were calculated at different energies(60,80,150,400,500,600,1000,1250,1500,and 2000 keV) by various theoretical methods such as fLUKA,GEANT4 Monte carlo(Mc) methods and XcOM program in this *** coefficients were also compared with the National Institute of Standards and Technology(NIST) *** results were highly in accordance with each other and NIST *** results showed that fLUKA was quite convenient in comparison to GEANT4 in the calculation of the mass attenuation coefficients of the used human body samples for low-energy photons(60,80,and 150 keV) when compared with the NIST values.

关键词：质量衰减系数蒙特卡洛方法 Geant4 部位 NIST 美国国家标准能量计算眼晶状体

A Geometric Distortion Solution Specifically for Historical Observations and its Implementation

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research in Astronomy and Astrophysics 2024年第11期24卷 85-94页

作者： f.r.Lin Q.Y.Peng Z.J.Zheng b.f.Guo School of Software Jiangxi Normal UniversityNanchang 330022China Sino-french Joint Laboratory for Astrometry Dynamics and Space ScienceJinan UniversityGuangzhou 510632China Department of computer Science Jinan UniversityGuangzhou 510632China Guangdong Ocean University Zhanjiang 524000China

Geometric distortion(GD)critically constrains the precision of *** well-established methods to correct GD requires calibration observations,which can only be obtained using a special dithering strategy during the observation ***,this special observation mode is not often used,especially for historical observations before those GD correction methods were *** a result,some telescopes have no GD calibration observations for a long period,making it impossible to accurately determine the GD *** limits the value of the telescope observations in certain astrometric scenarios,such as using historical observations of moving targets in the solar system to improve their *** investigated a method for handling GD that does not rely on the calibration *** this advantage,it can be used to solve the GD models of telescopes which were intractable in the *** method was implemented in Python and released on *** was then applied to solve GD in the observations taken with the 1 m and 2.4 m telescopes at Yunnan *** resulting GD models were compared with those obtained using well-established methods to demonstrate the ***,the method was applied in the reduction of observations for two targets,the moon of Jupiter(Himalia)and binary GSc 2038-0293,to show its *** GD correction,the astrometric results for both targets show ***,the mean residual between the observed and computed position(O-c)for binary GSc 2038-0293 decreased from 36 to 5 mas.

关键词： astrometry-methods data analysis-techniques image processing

NUMErIcAL SIMULATION Of MAcrO-SEGrEGATION IN STEEL INGOT DUrING SOLIDIfIcATION

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Acta Metallurgica Sinica(English Letters) 2004年第3期17卷 288-294页

作者： c.W.Ma H.f.Shen T.Y.Huang b.c.Liu Department of Mechanical Engineering Tsinghua University Beijing 100084 ChinaDepartment of Mechanical Engineering Tsinghua University Beijing 100084 ChinaDepartment of Mechanical Engineering Tsinghua University Beijing 100084 ChinaDepartment of Mechanical Engineering Tsinghua University Beijing 100084 China

A mathematical model coupling the momentum, energy and species conservation equa-tions was proposed to calculate the macro--segregation of fe--c alloy ingot during solid-ification. The corresponding simulation software which concurrently solves the macro-scopic mass, momentum, energy and species conservation equations has been developedby applying the SIMPLE algorithm.The thermo--solutal convection in a NH_4 cl--H_2O ingot is verified and the result showsgood agreement with that reported. Then macro--segregation in a steel ingot is simu-lated by using the developed program. The steel ingot is in a rectangular mold with ariser. The fluid flow is mainly induced by the temperature field and the solid fraction.The macro--segregation pattern is mainly affected by the thermo--induced convectionin the mushy zone. The negative segregation forms along the walls of the casting.The positive segregation forms at the top center of the casting into the riser. Thespecies concentration reaches the peak in the center of the ingot where solidificationends lastly.

关键词： macro-segregation thermo-solutal convection steel ingot numerical simulation

Infuence of elemental composition in environmental impacts of steel

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Journal of Iron and Steel research International 2020年第5期27卷 598-607页

作者： E.batuecas c.Mayo r.Diaz f.J.Perez Thermal and fluid Engineering Department Carlos III University of Madrid28911 LeganesMadridSpain chemical and Materials Engineering Department Complutense University of Madrid28040 MadridSpain Technical Sciences and Engineering UDIMA University28400 Collado VillalbaMadridSpain。

The environmental behavior of four steels was *** the operation phase of concentrating solar power plants,steels withstand high temperature because of its contact with molten ***,choosing the steel type for the molten salt tanks remains a great *** the cold tank,carbon steel is usually used although an approach with low chromium content steel is being studied for these ***,in high temperature applications,such as hot store tank,austenitic stainless steel is the most frequent ***,ferritic steel is being considered as a promising material in these *** many researchers studied the steel technical properties without considering their environmental damages,this work aimed to introduce the environmental aspects into the material choice by using the life cycle assessment *** one hand,the results showed the environmental adequacy of carbon steel against low chromium content *** the other hand,the results obtained in those steels suitable in high temperature application revealed signifcant environmental benefts from the ferritic steel instead of the austenitic steel.

关键词： renewable energy concentrating solar power Life cycle assessment Molten salt ferritic steel Austenitic steel