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Complementary Methods to Acquire the Kinematics of Swimming Snakes:A Basis to design Bio-inspired Robots

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Journal of Bionic Engineering 2023年第2期20卷 668-682页

作者： Elie Gautreau Xavier Bonnet Tom Fox Guillaume Fosseries Valéry Valle anthony Herrel Med Amine Laribi department of GMSC University of PoitiersISAE-ENSMACNRSPPRIME UPR 3346PoitiersFrance CEBC Center for Biological Studies of Chizé CNRS and University of la RochelleVilliers en BoisFrance MNHN National Museum of Natural History CNRSParisFrance

The vast diversity of morphologies,body size,and lifestyles of snakes represents an important source of information that can be used to derive bio-inspired robots through a biology-push and pull *** understanding of the detailed kinematics of swimming snakes is a fundamental prerequisite to conceive and design bio-inspired aquatic snake ***,only limited information is available on the kinematics of swimming *** and accurate methods are needed to fill this knowledge *** the present paper,three existing methods were compared to test their capacity to characterize the kinematics of swimming snakes.(1)Marker tracking(deftac),(2)Markerless pose estimation(deepLabCut),and(3)Motion capture were considered.(4)We also designed and tested an automatic video processing *** methods provided different albeit complementary data sets;they also involved different technical issues in terms of experimental conditions,snake manipulation,or processing *** tracking provided accurate data that can be used to calibrate other *** capture posed technical difficulties but can provide limited 3d *** pose estimation required deep learning(thus time)but was efficient to extract the data under various experimental ***,automatic video processing was particularly efficient to extract a wide range of data useful for both biology and robotics but required a specific experimental setting.

关键词： Locomotion Image processing Motion capture Kinematic analysis Snake robot Biomimicry deepLabCut

Large electromechanical strain at high temperatures of novel <001> textured BiFeGaO3-BaTiO3 based ceramics

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Journal of Materials Science & Technology 2020年第13期47卷 92-99页

作者： Jiangguli Peng Wenbin Liu Jiangtao Zeng Liaoying Zheng Guorong Li anthony Rousseau Alain Gibaud Abdelhadi Kassiba Key Laboratory of Inorganic Functional Material and device Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201899China Institut des Molécules et Matériaux du Mans(IMMM) CNRS UMR 6283Facultédes SciencesUniversitédu MaineAvenue O.Messiaen72085 Le MansCedex 09France Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

BiFeGaO3-BaTiO3(BFG-BT)based ceramics with a large piezoelectric coefficient are potential high performance lead-free piezoelectric *** this work,textured and random BFG-BT ceramics were realized by the solid state reaction method with and without BaTiO3(BT)*** ceramics were obtained by a reactive templated grain growth(RTGG)method leading to a high-temperature electromechanical strain of S=0.27%at 40 kV/cm and to an effective piezoelectric coefficient(d33*)up to 685 pm/V at 180℃.The easy movement of oriented domains enhanced the electromechanical strain under an applied electric field in textured sample(Lotgering factor f=66.3%).Structural investigations reveal that the proportion and degree of distortion of BFG-BT rhombohedral phase(R3c)reached its maximum in textured ceramics,resulting in large ferrodistortive displacements under electric *** addition,the dense nanodomains with low domain wall energies,inferred from the high-resolution transmission electron microscope(HR-TEM)observations,contribute to the extra displacement of the textured sample under an applied electric *** textured ceramics,the remnant polarization was stable(about 17μC/cm2)from room temperature to 180℃,contributing to the stable ferroelectric property at high *** the introduction of BT templates,high-density nanodomains were formed and the Burns temperature was enhanced in textured *** electromechanical strain,polarization and dielectric behavior were correlated to the textured or random forms of the BFG-BT based ceramics.

关键词： Textured ceramics Strain hysteresis Reactive templated grain growth dielectric responses

A novel image-based approach for interactive characterization of rock fracture spacing in a tunnel face

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第4期14卷 1077-1088页

作者： Jiayao Chen Yifeng Chen anthony G.Cohn Hongwei Huang Jianhong Man Lijun Wei Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Department of Geotechnical EngineeringTongji UniversityShanghai200092China School of Computing University of LeedsLeedsLS29JTUK department of Computer Science and Technology Tongji UniversityShanghai211985China School of Civil Engineering Shandong UniversityJinan250061China Luzhong Institute of Safety Environmental Protection Engineering and Materialsand School of Mechanical and Electrical EngineeringQingdao University of Science and TechnologyQingdao255000China

This paper presents a novel integrated method for interactive characterization of fracture spacing in rock tunnel *** main procedure includes four steps:(1)Automatic extraction of fracture traces,(2)digitization of trace maps,(3)disconnection and grouping of traces,and(4)interactive measurement of fracture set spacing,total spacing,and surface rock quality designation(S-RQd)*** evaluate the performance of the proposed method,sample images were obtained by employing a photogrammetrybased scheme in tunnel *** were then conducted to determine the optimal parameter values(*** threshold,angle threshold,and number of fracture trace grouping)for characterizing rock fracture *** applying the identified optimal parameters involved in the model,the proposed method could lead to excellent qualitative results to a new tunnel *** perform a quantitative analysis,three methods(***,straightening,and the proposed method)were employed in the same study and comparisons were *** proposed method agrees well with the field measurement in terms of the maximum and average values of measured spacing ***,the proposed method has reasonably good accuracy and interactive advantage for estimating the ultimate fracture spacing and *** can be a possible extension of existing methods for fracture spacing characterization for two-dimensional(2d)rock tunnel faces.

关键词： Fracture spacing Rock tunnel Image processing Fracture set grouping

High-fidelity replication of thermoplastic microneedles with open microfluidic channels

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Microsystems & Nanoengineering 2017年第1期3卷 96-106页

作者： Zahra Faraji Rad Robert E.Nordon Carl J.anthony Lynne Bilston Philip d.Prewett Ji-Youn Arns Christoph H.Arns Liangchi Zhang Graham J.davies Graduate School of Biomedical Engineering University of New South WalesSydneyNSW 2052Australia School of Mechanical Engineering University of BirminghamBirmingham B152TTUK School of Mechanical and Manufacturing Engineering University of New South WalesSydneyNSW 2052Australia Prince of Wales Clinical School University of New South WalesSydneyNSW 2052Australia School of Petroleum Engineering University of New South WalesSydneyNSW 2052Australia

development of microneedles for unskilled and painless collection of blood or drug delivery addresses the quality of healthcare through early intervention at *** with submicron to millimeter features have been fabricated from materials such as metals,silicon,and polymers by subtractive machining or ***,to date,large-scale manufacture of hollow microneedles has been limited by the cost and complexity of microfabrication *** paper reports a novel manufacturing method that may overcome the complexity of hollow microneedle *** microneedles with open microfluidic channels are fabricated by laser *** replicas are manufactured from these templates by soft-embossing with high fidelity at submicron *** manufacturing advantages are(a)direct printing from computeraided design(CAd)drawing without the constraints imposed by subtractive machining or etching processes,(b)high-fidelity replication of prototype geometries with multiple reuses of elastomeric molds,(c)shorter manufacturing time compared to three-dimensional stereolithography,and(d)integration of microneedles with open-channel *** work will address development of open-channel microfluidics for drug delivery,fluid sampling and analysis.

关键词： drug delivery laser lithography microneedles point-of-care diagnostics soft embossing

delonix regia and Casuarina equisetifolia as passive biomonitors and as bioaccumulators of atmospheric trace metals

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Journal of Environmental Sciences 2010年第7期22卷 1073-1079页

作者： Emmanuel Ehiabhi Ukpebor Justina Ebehirieme Ukpebor Emmanuel Aigbokhan Idris Goji Alex Okiemute Onojeghuo anthony Chinedum Okonkwo Air Pollution Research Group Department of ChemistryUniversity of Benin Lancaster Environment Centre Lancaster University department of Botany University of Benin Federal Ministry of Environment and Housing

The suitability of two common and ubiquitously distributed and exotic ornamental plant species in Nigeria-delonix regia and Casuarina equisetifolia as biomonitors and as effective bioaccumulators of atmospheric trace metals （Cd, Pb, Zn and Cu） has been evaluated. Bark and leaf samples from these plant species were collected in June and July 2006 at five locations in Benin City. Four of the sampling sites were in areas of high traffic density and commercial activities, the fifth site is a remote site, selected to act as a control and also to provide background information for the metals. The plant samples were collected and processed using standard procedures and trace metals were determined using atomic absorption spectrometer. The bark of the plants was able to bioaccumulate the trace metals, especially Pb which originates from anthropogenic contributions in the city. The Pb range of 20.00-70.00 μg/g measured for the bark samples ofd. regia, exceeded the normal plant Pb concentration of 0.2-20.0 μg/g and most Pb data available in literature. The bark of the plants was observed to accumulate more metals compared to the leave, while d. regia was found to be slightly better than C. equisetifolia in trace metal uptake efficiency. Spatial variations in the distributions of Pb and Zn were significant （p 〈 0.05）, and the continuous use of leaded fuel in Nigeria was identified as the predominant source of Pb in the atmosphere.

关键词： passive biomonitors trace metals delonix regia Casuarina equisetifolia

Morphometry and subpopulation structure of Holstein bull spermatozoa： variations in ejaculates and cryopreservation straws

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Asian Journal of Andrology 2016年第6期18卷 851-857页

作者： anthony Valverde Hector Arenan Maria Sancho Jesus Contell Jesus Yaniz Alejandro Fernandez Caries soler Technological Institute of Costa Rica San Carlos Campus S Xenetica Fontao Fontao-Esperante 27210 Lugo Spain R+d department Proiser R+D Scientific Park University of Valencia 46980 Paterna Spain department of Animal Production and Food Science Politechnical School of Huesca University of Zaragoza 22071 Huesca Spain department of Functional Biology and Physical Anthropology University of Valencia 46100 Burjassot Spain

Sperm quality is evaluated for the calculation of sperm dosage in artificial reproductive programs. The most common parameter used is motility, but morphology has a higher potential as a predictor of genetic quality. Morphometry calculations from CASA-Morph technology improve morphological evaluation and allow mathematical approaches to the problem. Semen from 28 Holstein bulls was collected by artificial vagina, and several ejaculates were studied. After general evaluation, samples were diluted, packaged in 0.25 ml straws, and stored in liquid nitrogen. Two straws per sample were thawed, and slides were processed and stained with diff-Quik. Samples were analyzed by a CASA-Morph system for eight morphometric parameters. In addition to the ＂classical＂ statistical approach, based on variance analysis （revealing differences between animals, ejaculates, and straws）, principal component （PC） analysis showed that the variables were grouped into PC1, related to size, and PC2 to shape. Subpopulation structure analysis showed four groups, namely, big, small, short, and narrow from their dominant characteristics, representing 31.0%, 27.3%, 24.1%, and 17.7% of the total population, respectively. The distributions varied between animals and ejaculates, but between straws, there were no differences in only four animals. This modern approach of considering an ejaculate sperm population as divided into subpopulations reflecting quantifiable parameters generated by CASA-Morph systems technology opens a new view on sperm function. This is the first study applying this approach to evaluate different ejaculates and straws from the same individual. More work must be done to improve seminal dose calculations in assisted reproductive programs.

关键词： cryopreservation Holstein bull sperm morphometry subpopulations

Morphometric comparison by the ISAS CASA-dNAf system of two techniques for the evaluation of dNA fragmentation in human spermatozoa

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Asian Journal of Andrology 2016年第6期18卷 835-839页

作者： Sara Sadeghi Almudena Garcia-Molina Ferran Celma anthony Valverde sogol Fereidounfar Caries soler department of Functional Biology and Physical Anthropology University of Valencia 46100 Burjassot Valencia Spain R+d department Proiser R+D Scientific Park Universitat de Valencia 46980 Paterna Valencia Spain Technological Institute of Costa Rica San Carlos Campus School of Agronomy 223-21001 Alajuela Costa Rica department of Botany Kharazmi University Tehran Iran

dNA fragmentation has been shown to be one of the causes of male infertility, particularly related to repeated abortions, and different methods have been developed to analyze it. In the present study, two commercial kits based on the SCd technique （Halosperm~ and SdFA） were evaluated by the use of the dNA fragmentation module of the ISAS vl CASA system. Seven semen samples from volunteers were analyzed. To compare the results between techniques, the Kruskal-Wallis test was used. data were used for calculation of Principal Components （two PCs were obtained）, and subsequent subpopulations were identified using the Halo, Halo/Core Ratio, and PC data. Results from both kits were significantly different （P 〈 0.001）. In each case, four subpopulations were obtained, independently of the classification method used. The distribution of subpopulations differed depending on the kit used. From the PC data, a discriminant analysis matrix was obtained and a good a posterioriclassification was obtained （97.1% for Halosperm and 96.6% for SdFA）. The present results are the first approach on morphometric evaluation of dNA fragmentation from the SCd technique. This approach could be used for the future definition of a classification matrix surpassing the current subjective evaluation of this important sperm factor.

关键词： dNA fragmentation Halosperm morphometry principal component analysis SdFA subpopulation

Sperm kinematic, head morphometric and kinetic- morphometric subpopulations in the blue fox （Alopex lagopus）

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Asian Journal of Andrology 2017年第2期19卷 154-159页

作者： Caries soler Jesus Contell Lorena Bori Maria Sancho Almudena Garcia-Molina anthony Valverde Jan Segarvall department of Functional Biology and Physical Anthropology University of Valencia 46100 Burjassot Spain R+d department Proiser R+D Scientific Park University of Valencia 46980 Paterna Spain Technological Institute of Costa Rica San Carlos Campus School of Agronomy 223-21001 Alajuela Costa Rica Finnish Fur Breeders Association ProFur 65101 Vaasa Finland

This work provides information on the blue fox ejaculated sperm quality needed for seminal dose calculations. Twenty semen samples, obtained by masturbation, were analyzed for kinematic and morphometric parameters by using CASA-Mot and CASA-Morph system and principal component （PC） analysis. For motility, eight kinematic parameters were evaluated, which were reduced to PC1, related to linear variables, and PC2, related to oscillatory movement. The whole population was divided into three independent subpopulations： SP1, fast cells with linear movement; SP2, slow cells and nonoscillatory motility; and SP3, medium speed cells and oscillatory movement. In almost all cases, the subpopulation distribution by animal was significantly different. Head morphology analysis generated four size and four shape parameters, which were reduced to PC 1, related to size, and PC2, related to shape of the cells. Three morphometric subpopulations existed. SPI： large oval cells; SP2： medium size elongated cells; and SP3. small and short cells. The subpopulation distribution differed between animals. Combining the kinematic and morphometric datasets produced PC1, related to morphometric parameters, and PC2, related to kinematics, which generated four sperm subpopulations - SPI.. high oscillatory motility, large and short heads; SP2; medium velocity with small and short heads; SP3. slow motion small and elongated cells; and SP4. high linear speed and large elongated cells. Subpopulation distribution was different in all animals. The establishment of sperm subpopulations from kinematic, morphometric, and combined variables not only improves the well-defined fox semen characteristics and offers a good conceptual basis for fertility and sperm preservation techniques in this species, but also opens the door to use this approach in other species, included humans.

关键词： integration of motility and morphology principal component analysis sperm morphometry subpopulation

diabetic Cardiovascular Risk and Carnitine deficiency <br/>—Carnitine deficiency in Clinical diabetes Mellitus

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Journal of diabetes Mellitus 2014年第3期4卷 202-208页

作者： John I. Malone Michael A. Malone anthony d. Morrison Charlotte Heart and Vascular Institute Port Charlotte FL USA department of Internal Medicine The University of South Florida Morsani College of Medicine Tampa FL USA

Background: Type 1 diabetes mellitus increases the risk of coronary heart disease. The Pittsburgh IddM morbidity and mortality study reported greater than 10 fold coronary heart disease mortality compared with US national data?[1]. Adults with diabetes have heart disease death rates 2 to 4 times higher than adults without diabetes [2]. diabetic cardiomyopathy explains much of this survival difference and carnitine deficiency is a cause of cardiomyopathy. Research design and Methods: Adult subjects (40) with type 1 diabetes mellitus were seen for a routine annual visit having no clinical complaints. Fasting serum samples were collected for annual chemistries and the measurement of carnitine. Results: The mean total (40.8 ± 8.8) [40 - 80 nmol/ml] and free (32.9 ± 7.9) [30 - 60 nmol/ml] carnitine levels for this group included 43% low total and 28% low free carnitine. The mean esterified/free (E/F) carnitine ratio (0.25 ± 0.09) for this group was elevated indicating carnitine insufficiency. Conclusions: Fatty acids are the primary energy source for diabetic heart muscle, and carnitine is essential for intracellular fatty acid transport and ATP production. Therefore, mild carnitine deficiency can compromise fatty acid energy production in a failing heart. Carnitine deficiency in subjects at high risk for cardiovascular failure is a possible unrecognized reason for the 4 fold increased death rate in patients with type 1 diabetes. Supplementation with oral carnitine could reduce that increased risk of heart failure, in patients with type 1 diabetes. Intravenous carnitine may be life saving when managing acute cardiac failure in patients with diabetes mellitus. Normal carnitine levels in patients with type 1 diabetes may provide a biochemical environment that prevents the long recognized idiopathic heart failure that occurs in insulin requiring diabetics as first reported in the 1974 Framingham Study.

关键词： Type 1 diabetes Mellitus Cardiovascular disease Heart Failure Reduced ATP Carnitine deficiency