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Increased attention to snake images in cynomolgus monkeys: an eye-tracking study

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动物学研究（英文） 2020年第1期41卷 32-38页

作者： Bo Zhang Zhi-Gang Zhou Yin Zhou Yong-Chang Chen Guangxi Key Laboratory of Brain and Cognitive Neuroscience Guilin Medical UniversityGuilinGuangxi 541199China Yunnan Key Laboratory of Primate Biomedicine Research Institute of Primate Translational MedicineKunming University of Science and TechnologyKunmingYunnan 650500China

Previous studies have revealed faster detection of snake images in humans and non-human primates(NHPs),suggesting automatic detection of evolutionary fear-relevant stimuli.Furthermore,human studies have indicated that general fear-relevance rather than evolutionary relevance is more effective at capturing attention.However,the issue remains unclarified in NHPs.Thus,in the present study,we explored the attentional features of laboratory-reared monkeys to evolutionary and general fear-relevant stimuli(e.g.,images of snakes,capturing gloves).Eye-tracking technology was utilized to assess attentional features as it can provide more accurate latency and variables of viewing duration and frequency compared with visual search task(VST)and response latency adopted in previous studies.In addition,those with autism spectrum disorder(ASD)show abnormal attention to threatening stimuli,including snake images.Rett syndrome(RTT)is considered a subcategory of ASD due to the display of autistic features.However,the attentional features of RTT patients or animal models to such stimuli remain unclear.Therefore,we also investigated the issue in MECP2 gene-edited RTT monkeys.The influence of different cognitive loads on attention was further explored by presenting one,two,or four images to increase stimulus complexity.The eye-tracking results revealed no significant differences between RTT and control monkeys,who all presented increased viewing(duration and frequency)of snake images but not of aversive stimuli compared with control images,thus suggesting attentional preference for evolutionary rather than general fear-relevant visual stimuli.Moreover,the preference was only revealed in visual tasks composed of two or four images,suggesting its cognitive-load dependency.

关键词： Non-human primates Attention snake Evolutionary relevance

Steering motion control of a snake robot via a biomimetic approach

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Frontiers of Information Technology & Electronic Engineering 2019年第1期20卷 32-44页

作者： Wenjuan OUYANG Wenyu LIANG Chenzui LI Hui ZHENG Qinyuan REN Ping LI State Key Laboratory of Industrial Control Technology Zhejiang University Department of Electrical and Computer Engineering National University of Singapore Zhejiang University of Science and Technology

We propose a biomimetic approach for steering motion control of a snake robot. Inspired by a vertebrate biological motor system paradigm, a hierarchical control scheme is adopted. In the control scheme, an artificial central pattern generator(CPG) is employed to generate serpentine locomotion in the robot. This generator outputs the coordinated desired joint angle commands to each lower-level effector controller, while the locomotion can be controlled through CPG modulation by a higher-level motion controller. The motion controller consists of a cerebellar model articulation controller(CMAC) and a proportional-derivative(PD) controller. Because of the fast learning ability of the CMAC, the proposed motion controller can drive the robot to track the desired orientation and adapt to unexpected perturbations. The PD controller is employed to expedite the convergence speed of the motion controller. Finally, both numerical studies and experiments proved that the proposed approach can help the snake robot achieve good tracking performance and adaptability in a varying environment.

关键词： snake robot Central pattern generator Cerebellar model articulation controller

Design and Development of a Wheel-less snake Robot with Active Stiffness Control for Adaptive Pedal Wave Locomotion

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Journal of Bionic Engineering 2019年第4期16卷 593-607页

作者： Mohammadali Javaheri Koopaee Sander Bal Christopher Pretty Xiaoqi Chen Mechanical Engineering Department University of CanterburyChristchurch 8041New Zealand Manufacturing Futures Research Institute Swinburne University of TechnologyHawthorn 3122Australia

This paper presents the design and manufacture process of a wheel-less,modular snake robot with series elastic actuators to reliably measure motor torque signal and investigate the effectiveness of active stiffness control for achieving adaptive snake-like locomotion.A polyurethane based elastic element to be attached between the motor and the links at each joint was designed and manufactured using water jet cutter,which makes the final design easier to develop and more cost-effective,compared to existing snake robots with torque measurement capabilities.The reliability of such torque measurement mechanism was examined using simulated dynamical model of pedal wave motion,which proves the efficacy of the design.A distributed control system was also designed,which with the help of an admittance controller,enables active control of the joint stiffness to achieve adaptive snake robot pedal wave locomotion to climb over obstacles,which unlike existing methods does not require prior information about the location of the obstacle.The effectiveness of the proposed controller in comparison to open-loop control strategy was verified by the number of experiments.The results show the capability of the robot to successfully climb over obstacles with the height of more than 55%of the diameter of the snake robot modules.

关键词： modular snake robot series elastic actuator active stiffness control pedal wave locomotion adaptive locomotion

Confined spaces path following for cable-driven snake robots with prediction lookup and interpolation algorithms

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Science China(Technological Sciences) 2020年第2期63卷 255-264页

作者： TANG Lei ZHU LiMin ZHU XiangYang GU GuoYing Robotics Institute School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

While cable-driven snake robots are promising in exploring confined spaces, their hyper-redundancy makes the collision-free motion planning difficult. In this paper, by combining the prediction lookup and interpolation algorithms, we present a new path following method for cable-driven snake robots to high-efficiently slither into complex terrains along a desired path. In our method, we first discretize the desired path into points, and develop the prediction lookup algorithm to efficiently find the points matched with joints of the robot. According to geometric relations between the prediction lookup results and link length of the robot, we develop the interpolation algorithm to reduce the tracking errors caused by the discretization. Finally, simulations and experiments of inspections in two confined spaces including the obstacle array and pipe tank system are performed on our custom-built 25 degree of freedoms(DOFs) cable-driven snake robot. The results demonstrate that the presented method can successfully navigate our snake robot into confined spaces with high computational efficiency and good accuracy, which well verifies effectiveness of our development.

关键词： cable-driven snake robot confined spaces path following prediction lookup interpolation

The genome and transcriptome analysis of snake gourd provide insights into its evolution and fruit development and ripening

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Horticulture Research 2020年第1期7卷 204-218页

作者： Lili Ma Qing Wang Jianlou Mu Anzhen Fu Changlong Wen Xiaoyan Zhao Lipu Gao Jian Li Kai Shi Yunxiang Wang Xuewen Zhang Xuechuan Zhang Zhangjun Fei Donald Grierson Jinhua Zuo Key Laboratory of Vegetable Postharvest Processing Ministry of AgricultureBeijing Key Laboratory of Fruits and Vegetable Storage and ProcessingKey Laboratory of Biology and Genetic Improvement of Horticultural Crops(North China)of Ministry of AgricultureKey Laboratory of Urban Agriculture(North)of Ministry of AgricultureThe Collaborative Innovation Center of Cucurbit CropsBeijing Vegetable Research CenterBeijing Academy of Agriculture and Forestry SciencesBeijing 100097China College of Food Science and Technology Hebei Agricultural UniversityBaoding 071001China Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Technology and Business UniversityBeijing 100048China Department of Horticulture Zhejiang UniversityHangzhou 310058China Biomarker Technologies Corporation Beijing 101300China Boyce Thompson Institute for Plant Research Cornell UniversityIthacaNY 14853USA U.S.Department of Agriculture-Agricultural Research Service Robert W.Holley Center for Agriculture and HealthIthacaNY 14853USA School of Biosciences University of NottinghamSutton Bonington CampusLoughboroughLeicestershire LE125RDUK

snake gourd(Trichosanthes anguina L.),which belongs to the Cucurbitaceae family,is a popular ornamental and food crop species with medicinal value and is grown in many parts of the world.Although progress has been made in its genetic improvement,the organization,composition,and evolution of the snake gourd genome remain largely unknown.Here,we report a high-quality genome assembly for snake gourd,comprising 202 contigs,with a total size of 919.8 Mb and an N50 size of 20.1 Mb.These findings indicate that snake gourd has one of the largest genomes of Cucurbitaceae species sequenced to date.The snake gourd genome assembly harbors 22,874 protein-coding genes and 80.0%of the genome consists of repetitive sequences.Phylogenetic analysis reveals that snake gourd is closely related to sponge gourd but diverged from their common ancestor~33–47 million years ago.The genome sequence reported here serves as a valuable resource for snake gourd genetic research and comparative genomic studies in Cucurbitaceae and other plant species.In addition,fruit transcriptome analysis reveals the candidate genes related to quality traits during snake gourd fruit development and provides a basis for future research on snake gourd fruit development and ripening at the transcript level.

关键词： snake evolution snake

Parallels between Russell's viper(Daboia russelii) and hump-nosed viper(Hypnak species) bites in the central hills of Sri Lanka amidst the heavy burden of unidentified snake bites

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Asian Pacific Journal of Tropical Medicine 2011年第7期4卷 564-567页

作者： Keerthi Kularatne Sudhara Budagoda Kalana Maduwage Kamal Naser Rangith Kumarasiri Senanayake Kularatne Teaching Hospital PeradeniyaSri Lanka Department of Medicine Faculty of MedicinePeradeniya UniversitySri Lanka Faculty of Medicine Peradeniya UniversitySri Lanka

Objective:To describe the epidemiology of snake bite in the region and attempt to compare proven Russell’s viper with hump-nosed viper bites.Methods:All snake bite admissions to the Toxicology Unit of Teaching Hospital Peradeniya over three year from 2006 were included. Results:Of the 776 snakebites,665(86%) were unidentified and non-envenomed.Humpnosed viper and Russell’s viper accounted for 55(7%) and 40(5%) bites respectively,of them, incriminated snakes were found in 36(65%) and 19(48%) cases.The cobra bites-5,krait bites-0. The median ages:Russell’s viper bites-41(range 16-66),hump-nosed viper bites-42(range 15- 75).The gender incidence,time of bite(>58%daytime) were similar.In hump-nosed viper bite; upper limb involved in 13(36%),happened at home garden in 22(61%),none in paddy fields.In Russell’s viper bite;6(33%) occurred in paddy fields.Dry bites were similar at 5%.In humpnosed viper bite:local effects 94%,coagulopathy 3%,acute renal failure 3%and one patient died.In Russell’s viper bite;local effects 84%,coagulopathy 53%,neurotoxicity 21%.Abdominal pain occurred only in Russell’s viper bites 10(53%).Conclusions:Overwhelming numbers of unidentified,non-envenomed snakebites are common in the central hills.Some distinctive differences were observed between Russell’s viper and hump-nosed viper bites.

关键词： Russell’s viper Hump-nosed viper Unidentified snake bites Non-poisonous snake bites Sri Lanka Epidemiology

Adaptive Evolution of the Ventral Scale Microornamentations among Three snake Species

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Asian Herpetological Research 2020年第4期11卷 365-372页

作者： Kexin WANG Yutian ZHAO Chaochao HU Hong LI Yanfu QU Xiang JI Jiangsu Key Laboratory for Biodiversity and Biotechnology College of Life SciencesNanjing Normal UniversityNanjing 210046JiangsuChina

Research on the ecological effect of microronamentations on the scale surface in reptiles has been carried out over the past few decades.It is found that the microornamentation pattern in reptiles is related to their habitats.This study examined the wettability on scale surface,as well as the differences in microornamentation on ventral scales from the mid-body region in three snake species,Hypsiscopus plumbea(aquatic),Oocatochus rufodorsata(semi-aquatic) and Elaphe carinata(terricolous).Moreover,the scale specimens were metallized and analyzed using scanning electron microscopy.Our results showed that there are microornamentations on the ventral scale surfaces of the tested species,which showed interspecific differences.To be specific,the aquatic snake shows the narrow,fine and regular denticulations which are connected to reduce friction and dirt shedding.By contrast,the terrestrial snake acquired the wider and shorter denticulation which would render more friction during locomotion but it shows greater water resistance to improve the capacity of dirt shedding and compensate for the disadvantage of short and wide denticulations.Additionally,the denticulation characteristics of the semi-aquatic snake fell in between those of aquatic and terrestrial snakes.Therefore,it is deduced in this study that the ventral scale microornamentations in snakes contribute to ecological adaptation to their preferential microhabitats.

关键词： Elaphe carinata Hypsiscopus plumbea Oocatochus rufodorsata scale microornamentation snake wettabiligy

The loss of sexual size dimorphism in urban populations of a widespread reptile,the European grass snake Natrix natrix

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Current Zoology 2020年第2期66卷 217-218页

作者： Stanistaw BURY Bartlomiej ZAJAC Institute of Environmental Sciences Jagiellonian UniversityGronostajowa 7Krakow30-387Poland

Ciries represent a unique ecosystem dominated by humans and highdensity man-made infrastructure,associated with modifications or entire loss of local habitats.Thus,urbanization constitutes a consid-erable challenge for wildlife,and only a minority of species is able to persist in cities(Niemela et al.2011).Species that maintain popula-tions in cities are usually characterized by significant changes in life history characteristics,population structure,and ecological relations(Niemela et al.2011).

关键词： body size Natrix sexual dimorphism snake urban ecology

Therapeutic potential of snake venom in cancer therapy:current perspectives

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Asian Pacific Journal of Tropical Biomedicine 2013年第2期3卷 156-162页

作者： Vivek Kumar Vyas Keyur Brahmbhatt Hardik Bhatt Utsav Parmar Institute of Pharmacy Nirma UniversityAhmadabad 382481GujaratIndia Arihant School of Pharmacy and Bio Research Institute

Many active secretions produced by animals have been employed in the development of new drugs to treat diseases such as hypertension and cancer.snake venom toxins coutributed significantly to the treatment of many medical conditions.There are many published studies describing and elucidating the anti-cancer potential of snake venom.Cancer therapy is one of the main areas for the use of protein peptides and enzymes originating from animals of different species.Some of these proteins or peptides and enzymes from snake venom when isolated and evaluated may bind specifically to cancer cell membranes,affecting the migration and proliferation of these cells.Some of substances found in the snake venom present a great potential as anti-tumor agent.In this review,we presented the main results of recent years of research involving the active compounds of snake venom that have anticancer activity.

关键词： snake venom Cytotoxin Anticancer agents Apoptosis inducer