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Hierarchical Voronoi Structure Inspired by Cat Paw Pads Substantially Enhances Landing Impact Energy dissipation

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Journal of Bionic Engineering 2024年第4期21卷 1847-1861页

作者： da Lu Baoqing Pei Yangyang Xu Mengyuan Hu Shijia Zhang Le Zhang Xin Huang Yangwei Wang Xueqing Wu Beijing Key Laboratory for design and Evaluation Technology of Advanced Implantable&Interventional Medical devices Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang University100083BeijingChina National Key Laboratory of Science and Technology on Materials under Shock and Impact Beijing Institute of Technology100081BeijingChina Shenzhen Institute of Beihang University 518000ShenzhenChina

When a human lands from a high drop,there is a high risk of serious injury to the lower *** the other hand,cats can withstand jumps and falls from heights without being fatally wounded,largely due to their impact-resistant paw *** aim of the present study was to investigate the biomechanism of impact resistance in cat paw pads,propose an optimal hierarchical Voronoi structure inspired by the paw pads,and apply the structure to bionic cushioning shoes to reduce the impact force of landing for *** microstructure of cat paw pads was observed via tissue section staining,and a simulation model was reconstructed based on CT to verify and optimize the structural cushioning *** distribution pattern,wall thickness of compartments,thickness ratio of epidermis and dermis,and number of compartments in the model were changed and simulated to achieve an optimal composed structure.A bionic sole was 3d-printed,and its performance was evaluated via compression test and a jumping-landing *** results show that cat paw pads are a spherical cap structure,divided from the outside to the inside into the epidermis,dermis,and compartments,each with different cushioning capacities.A finite element simulation of different cushioning structures was conducted in a cylinder with a diameter of 20 mm and a height of 10 mm,featuring a three-layer *** optimal configuration of the three layers should have a uniform distribution with 0.3–0.5 mm wall thickness,a 1:1–2 thickness ratio of epidermis and dermis,and 100–150 compartments.A bionic sole with an optimized structure can reduce the peak impact force and delay the peak arrival *** energy absorption rate is about 4 times that of standard *** jumping 80,100,and 120 cm,the normalized ground reaction force is also reduced by 8.7%,12.6%and 15.1%compared with standard *** study provides theoretical and technical support for effective protection against human lower limb landing injuries.

关键词： Cat paw pads Hierarchical Voronoi structure Landing impact Energy dissipation Bionic sole

Influence of previous plane of nutrition on molecular mechanisms regulating the expression of urea and water metabolism related genes in the rumen and kidney of finishing crossbred Angus steers

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Animal Nutrition 2024年第2期17卷 232-243页

作者： Aghata E.Moreira da Silva Arturo Macias Franco Bradley S.Ferguson Mozart A.Fonseca College of Agriculture Biotechnology&Natural Resources University of Nevada department of Animal and Range Sciences Clayton Livestock Research Center New Mexico State University

This study aimed to understand how molecular mechanisms controlling water and urea metabolism at the finishing phase can be affected by previous plane of nutrition of crossbred Angus beef steers. Twentyfour(n = 24) animals were randomly distributed into either a moderate(MP) or high plane of nutrition during the background phase for 85 d. Animals were then blocked by their previous plane and were moved onto a 105-d finishing phase in a 2 × 2 factorial arrangement. The forage-finished group received only high-quality alfalfa hay, whereas the grain-fed group received a high grain diet(80% whole corn and20% alfalfa hay). By the end of the finishing phase, animals were harvested and tissue samples from the rumen and kidney were collected. Changes in gene expression of aquaporins(AQP)-2,-3,-4,-7, ATP1A1,ATP1B1, SGK1, CLIC1(kidney and rumen), UT-A1(kidney only) and UT-B(rumen only), were assayed via real-time q PCR; 18S r RNA was used as an endogenous control. One-way ANOVA followed by Tukey's post hoc analysis was conducted. When animals were from MP, forage-finishing increased the relative abundance of AQP3(P ≤ 0.05), AQP7(P ≤ 0.05), ATP1B1(P ≤ 0.05), and SGK1(P ≤ 0.05) in the kidney when compared to grain-fed animals. In the rumen, for the MP group, AQP7 was differentially expressed in both treatments at the finishing phase(P ≤ 0.01), with forage-finished steers having the highest expression of AQP7. For the MP group, UT-B had a tendency of presenting a higher expression on grainfed animals(P = 0.075). Overall, these results suggest that previous plane can impact expression of genes associated with water and urea metabolism during the finishing phase, namely AQP3, AQP7, ATP1B1, and SGK1 in the kidney, and AQP7 and UT-B in the rumen. The greatest impact observed on gene expression changes of investigated genes at the finishing phase was reflective of animals backgrounded on the moderate previous plane.

关键词： Gene expression Aquaporin Sodium channel Urea transporter

Effect of Plastic deformation on Microstructure and Properties of Cu-(1 wt%-6 wt%) Ag Alloy

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 747-753页

作者：茹亚东 ZHANG Zhongyuan 高召顺 ZHANG Ling ZUO Tingting XUE Jiangli TANG Zhixiang da Bo LIU Yongsheng XIAO Liye Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China department of Physics Shanghai University of Electric PowerShanghai 201306China University of Chinese Academy of Sciences Beijing 100190China International Joint Labora-tory for Light Alloys(MOE) College of Materials Science and EngineeringChongqing UniversityChongqing 400044China Research and Services division of Materials da.a.a.d Integrated System National Institute for Materials ScienceTsukuba 305-0047Japan

In the present study,the Cu-(1 wt%-6 wt%)Ag alloys were prepared by melting,forging and wire *** effects of plastic deformation on microstructure evolution and properties of the alloys were *** results show that non-equilibrium eutectic colonies exist in the Cu-(3 wt%-6 wt%)Ag alloy and no eutectic colonies in the 1 wt%-2 wt%Ag containing *** eutectic colonies are aligned along the drawing direction and refined with the increase of draw *** to the refinement of eutectic colonies,the Cu-Ag alloy exhibits higher strength with the increase of draw *** Cu-6Ag alloy exhibits excellent comprehensive properties with a strength of 930 MPa and a conductivity of 82%IACS when the draw ratio reaches 5.7.

关键词： Cu-Ag alloy high strength and high conductivity microstructure eutectic structure strengthening mechanism

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Advancing Wound Filling Extraction on 3d Faces:An Auto-Segmentation and Wound Face Regeneration Approach

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 2197-2214页

作者： duong Q.Nguyen Thinh d.Le Phuong d.Nguyen Nga T.K.Le H.Nguyen-Xuan department of Mathematics and Statistics Quy Nhon UniversityQuy Nhon City55100Viet Nam Applied Research Institute for Science and Technology Quy Nhon UniversityQuy Nhon City55100Viet Nam CIRTECH Institute HUTECH UniversityHo Chi Minh City72308Viet Nam

Facial wound segmentation plays a crucial role in preoperative planning and optimizing patient outcomes in various medical *** this paper,we propose an efficient approach for automating 3d facial wound segmentation using a two-stream graph convolutional *** method leverages the Cir3d-FaIR dataset and addresses the challenge of data imbalance through extensive experimentation with different loss *** achieve accurate segmentation,we conducted thorough experiments and selected a high-performing model from the *** selectedmodel demonstrates exceptional segmentation performance for complex 3d facial ***,based on the segmentation model,we propose an improved approach for extracting 3d facial wound fillers and compare it to the results of the previous *** method achieved a remarkable accuracy of 0.9999993% on the test suite,surpassing the performance of the previous *** this result,we use 3d printing technology to illustrate the shape of the wound *** outcomes of this study have significant implications for physicians involved in preoperative planning and intervention *** automating facial wound segmentation and improving the accuracy ofwound-filling extraction,our approach can assist in carefully assessing and optimizing interventions,leading to enhanced patient ***,it contributes to advancing facial reconstruction techniques by utilizing machine learning and 3d bioprinting for printing skin tissue *** source code is available at https://***/SIMOGroup/WoundFilling3d.

关键词： 3d printing technology face reconstruction 3d segmentation 3d printed model

Tumor necrosis factor α deficiency promotes myogenesis and muscle regeneration

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Zoological Research 2024年第4期45卷 951-960页

作者： Yu Fu Jing-Ru Nie Peng Shang Bo Zhang da-Wei Yan Xin Hao Hao Zhang State Key Laboratory of Animal Biotech Breeding China Agricultural UniversityBeijing 100193China College of Animal Science Xizang Agricultural and Animal Husbandry UniversityLinzhiXizang 860000China College of Animal Science and Technology Yunnan Agricultural UniversityKunmingYunnan 650201China

Tumor necrosis factorα(TNFα)exhibits diverse biological functions;however,its regulatory roles in myogenesis are not fully *** the present study,we explored the function of TNFαin myoblast proliferation,differentiation,migration,and myotube fusion in primary myoblasts and C2C12 *** this end,we constructed TNFαmuscle-conditional knockout(TNFα-CKO)mice and compared them with flox mice to assess the effects of TNFαknockout on skeletal *** indicated that TNFα-CKO mice displayed phenotypes such as accelerated muscle development,enhanced regenerative capacity,and improved exercise endurance compared to flox mice,with no significant differences observed in major visceral organs or skeletal *** label-free proteomic analysis,we found that TNFα-CKO altered the distribution of several muscle development-related proteins,such as Hira,Casz1,Casp7,Arhgap10,Gas1,diaph1,Map3k20,Cfl2,and Igf2,in the nucleus and *** set enrichment analysis(GSEA)further revealed that TNFαdeficiency resulted in positive enrichment in oxidative phosphorylation and Myod targets and negative enrichment in JAK-STAT *** findings suggest that TNFα-CKO positively regulates muscle growth and development,possibly via these newly identified targets and pathways.

关键词： TNFα Muscle-conditional knockout Myogenesis Regeneration Muscle development

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Structural changes in the obese brain

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Neural Regeneration Research 2024年第12期19卷 2561-2562页

作者： Anna R.R.da Conceicao Marcelo N.N.Vieira Fernanda G.de Felice d’Or Institute for Research and Education Rio de JaneiroBrazil Institute of Medical Biochemistry Leopoldo de Meis Federal University of Rio de JaneiroRio de JaneiroBrazil Centre for Neuroscience Studies Department of Biomedical and Molecular Sciences&Department of PsychiatryQueen’s UniversityKingstonONCanada

Obesity represents a major global health concern,with widespread growing prevalence and severe consequences for the quality of life and life expectancy of affected individuals and for the economic burden of healthcare systems(Prospective Studies Collaboration,2009).Obesity is a well-established risk factor for a variety of conditions including metabolic,vascula r,and heart diseases,and seve ral types of cancer(Prospective Studies Collaboration,2009).

关键词： diseases consequences prevalence

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Analysis of the Influence of Geometrical Parameters on the Performance of a Proton Exchange Membrane Fuel Cell

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Fluid dynamics & Materials Processing 2024年第1期20卷 219-237页

作者： Guodong Zhang Huifang Tao da Li Kewei Chen Guoxiang Li Shuzhan Bai Ke Sun School of Energy and Power Engineering Shandong UniversityJinan250061China Sinotruk Jinan Special Purpose Vehicle Co. Ltd.Jinan250117China

A suitable channel structure can lead to efficient gas distribution and significantly improve the power density of fuel *** this study,the influence of two channel design parameters is investigated,namely,the ratio of the channel width to the bipolar plate ridge width(i.e.,the channel ridge ratio)and the channel *** impact of these parameters is evaluated with respect to the flow pattern,the gas composition distribution,the temperature field and the fuel cell output *** results show that a decrease in the channel ridge ratio and an increase in the channel depth can effectively make the distributions of velocity,temperature and concentration more uniform in each channel and improve the output capability of the fuel *** increase in the channel ridge ratio and depth obviously reduces the flow resistance and improves the flow characteristics.

关键词： Hydrogen fuel cell bipolar plate flow channel multiphysics coupling

N-glycosylation of Wnt3 regulates the progression of hepatocellular carcinoma by affecting Wnt/β-catenin signal pathway

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2769-2780页

作者： Xin-Zhan Zhang Xiao-Chuan Mo Zhu-Ting Wang Rong Sun da-Quan Sun department of Biochemistry and Molecular Biology&Research Center for Basic Medical Sciences Guizhou Medical UniversityGuiyang 550025Guizhou ProvinceChina

BACKGROUNd Wnt/FZd-mediated signaling pathways are activated in more than 90%of hepatocellular carcinoma(HCC)cell *** a well-known secretory glycoprotein,Wnt3 can interact with FZd receptors on the cell surface,thereby activating the Wnt/β-catenin signaling ***,the N-glycosylation modification site of Wnt3 and the effect of this modification on the biological function of the protein are still *** To investigate the effect of Wnt3 N-glycosylation on the biological function of HCC *** Site-directed mutagenesis was used to verify the Wnt3 N-glycosylation sites,actinomycin d treatment was used to detect the stability of Wnt3 after site-directed mutation,the binding of the N-glycosylation site-directed mutant Wnt3 to FZd7 was observed by laser confocal microscopy,and the effects of the N-glycosylation site-directed mutation of Wnt3 on the Wnt/β-catenin signaling pathway and the progression of HCC cells were detected by western blot and cell function *** Wnt3 has two N-glycosylation-modified sites(Asn90 and Asn301);when a single site at amino acid 301 is mutated,the stability of Wnt3 is weakened;the binding ability of Wnt3 to FZd7 decreases when both sites are mutated simultaneously;and the level of proteins related to the Wnt/β-catenin signaling pathway is *** proliferation,migration and invasion are also weakened in the case of single 301 site and double-site *** These results indicate that by inhibiting the N-glycosylation of Wnt3,the proliferation,migration,invasion and colony formation abilities of liver cancer cells can be weakened,which might provide new therapeutic strategies for clinical liver cancer in the future.

关键词： Wnt3 N-glycosylation Hepatocellular carcinoma Liver cancer Wnt/β-catenin FZd7

Specialized springtail predation by Loricera beetles: An example of evolutionary stasis across the K-Pg extinction

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The Innovation 2024年第3期5卷 25-26页

作者： Yan-da Li Erik Tihelka Michael SEngel diying Huang Chenyang Cai State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China department of Earth Sciences University of CambridgeCambridge CB23EQUK Bristol Palaeobiology Group School of Earth SciencesUniversity of BristolBristol BS81TQUK division of Invertebrate Zoology American Museum of Natural HistoryNew YorkNY 10024-5192USA Facultad de Ciencias Biológicas Universidad Nacional Mayor de San MarcosLima 15081Perú departamento de Entomología Museo de Historia NaturalUniversidad Nacional Mayor de San MarcosLima 15072Perú

dear Editor,The Cretaceous-Paleogene(K-Pg)mass extinction precipitated one of the most profound restructurings of biodiversity in recent geological *** the extinction of many iconic groups,particularly the non-avian dinosaurs,there is emerging evidence that previously overlooked taxa experienced stark morphological and evolutionary *** this study,we report both adult and larva of beetles of the genus Loricera preserved in mid-Cretaceous Kachin amber(Figure 1),which display striking similarity to extant congeners,indicating a stasis of their specialized feeding behavior persisting at least 100 million years.

关键词： extinction Figure Cretaceous