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基于循序渐进方式的Python-turtle库教学设计
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作者 尹建新 胡彦蓉 《中国信息技术教育》 2024年第8期71-75,共5页
本文针对turtle绘图一堂课的实践教学,以任务为驱动,全面覆盖turtle知识点,以循序渐进方式将内容综合融入其中,结合线上线下混合式课堂,引导学生找到解决问题的方法,极大地提高了学生的编程兴趣,培养了学生的创新思维。
关键词 任务驱动 循序渐进 线上线下混合课堂 turtle
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The first record of dermochelyid turtles in the Eocene of Tierra del Fuego:new insights on the evolution of the Weddellian faunas
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作者 Paula BONA Juliana STERLI +3 位作者 Marcelo Saúl de la FUENTE Eduardo OLIVERO Marta S.FERNÁNDEZ Marcelo REGUERO 《Advances in Polar Science》 CSCD 2024年第1期63-77,共15页
The Antarctic Paleogene marine fossil record has been the key to reconstructing the evolution of the Weddellian Sea and final dismemberment of Southern Gondwana.In this context,Eocene marine vertebrates from Seymour(M... The Antarctic Paleogene marine fossil record has been the key to reconstructing the evolution of the Weddellian Sea and final dismemberment of Southern Gondwana.In this context,Eocene marine vertebrates from Seymour(Marambio)Island have provided valuable information.We present the first Eocene record of marine reptiles from the southern Atlantic Coast of South America.This corresponds to several postcranial turtle remains represented by a proximal end of the right humerus,three caudal and one thoracic vertebrae,a fragment of the left pubis,and ten ossicles of the dorsal carapace,coming from the Leticia Formation(late-mid Eocene)at Cabo Tiburones,Tierra del Fuego,Argentina.These materials show severalfeatures such as the size and general morphology of the humerus and vertebrae,and the presence of relatively small,irregular,smooth,and unkeeled ossicles,which allow us to assign them to Dermochelyidae indet.Dermochelyids are a cosmopolitan group ofcryptodiran turtles,registered from the late Cretaceous up to the recent,with some physiological-biological peculiarities(e.g.,endothermy and an exclusive jellyfish-based diet)and characterized by the presence of an osseous carapace formed by ossicles.The new finding from the Leticia Formation is an addition to the scarce and extremely fragmentary record of Eocene dermochelyids from the southern seas like those from the La Meseta and Submeseta formations(Antarctica)and the Waihao and Burnside formations(New Zealand).This new information allows us to discuss the presence of these turtles in such high latitudes in the past and its implication in the evolution of the Weddellian fauna. 展开更多
关键词 marine reptiles sea turtles Dermochelyidae PALEOGENE La Meseta Formation Submeseta Formation Leticia Formation
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基于Python语言的Turtle库绘图实例 被引量:1
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作者 林晓芬 《电脑知识与技术》 2023年第3期97-98,102,共3页
Python语言语法简洁、清晰、易读。学生在学习Python语言时,学习难度起点低,容易入门。国内许多高校都开设了Python程序设计课程。Python语言的Turtle库设计巧妙,作图模型简单强大。初学者能很快编写出趣味生动的作图程序,极大地提高了... Python语言语法简洁、清晰、易读。学生在学习Python语言时,学习难度起点低,容易入门。国内许多高校都开设了Python程序设计课程。Python语言的Turtle库设计巧妙,作图模型简单强大。初学者能很快编写出趣味生动的作图程序,极大地提高了学习者的兴趣和积极性。 展开更多
关键词 PYTHON语言 turtle
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A Meta-analysis of the spirit turtle eight method Acupuncture Therapy for Insomnia
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作者 CHEN Bo-xin ZENG Nian-peng +1 位作者 KUANG Yu-lian ZHAO Cai-jiao 《Journal of Hainan Medical University》 CAS 2023年第7期61-68,共8页
Objective:To systematically evaluate the efficacy and safety of the spirit turtle eight method acupuncture therapy in the treatment of insomnia,to better serve the clinic and provide reference ideas for the treatment ... Objective:To systematically evaluate the efficacy and safety of the spirit turtle eight method acupuncture therapy in the treatment of insomnia,to better serve the clinic and provide reference ideas for the treatment of insomnia.Methods:Search CNKI,CBM,Wanfang,Weipu,China Clinical Trial Registry databases on the use of the spirit turtle eight method compared with others interventions to treat insomnia.The search period is from the library until August 1,2021,two researchers will conduct independent quality evaluation and effect size extraction on the literature,and use STATA16.0 and Review5.3 to conduct Meta analysis and quality evaluation on the literature.Through screening,a total of 18 eligible documents participated in the meta-analysis,with a total of 1583 cases.Results:①The effective rate of the spirit turtle eight method in the treatment of insomnia is higher than the control group[RR=1.213,95%CI(1.155,1.274),Z=7.71,P<0.01];②The Pittsburgh Sleep Quality Index(PSQI)score is lower than other acupuncture treatments[WMD=-2.33,95%CI(-2.75,-1.91),Z=10.97,P<0.01];③The one-month follow-up PSQI score after the treatment of insomnia by the spirit turtle eight method is lower than the control group[WMD=-3.263,95%CI(-3.446,-3.080),Z=34.96,P<0.01];④No studies have reported serious adverse reactions in the treatment group and control group.Conclusion:Based on the current research,the spirit turtle eight method are better than the control group in the treatment of insomnia,and are suitable for clinical application.However,more high-quality clinical studies are still needed to prove its efficacy. 展开更多
关键词 Spirit turtle eight method Acupuncture Treatment INSOMNIA Meta Analysis
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Effects of Pesticide Exposure on Embryonic Development and Hatchling Traits of Turtles 被引量:5
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作者 Baofeng WU Liang LIANG +1 位作者 Liang MA Weiguo DU 《Asian Herpetological Research》 SCIE CSCD 2016年第1期28-33,共6页
Deltamethrin is a widespread environmental hormone with endocrine-disrupting properties, but its effect on embryonic development of reptiles is largely unexplored. We investigated the effects of deltamethrin on embryo... Deltamethrin is a widespread environmental hormone with endocrine-disrupting properties, but its effect on embryonic development of reptiles is largely unexplored. We investigated the effects of deltamethrin on embryonic development and offspring traits in two turtle species, one with parchment-shelled eggs and the other with rigidshelled eggs. Deltamethrin exposure during egg incubation did not affect hatching success and hatchling body size in either species. However, embryonic exposure to deltamethrin resulted in reduced hatchling locomotor performance in the red-eared slider turtle(Trachemys scripta) with parchment-shelled eggs, but not in the Chinese three-keeled pond turtle(Chinemys reevesii) with rigid-shelled eggs. These results suggest that parchment-shelled eggs are likely more vulnerable to deltamethrin than rigid-shelled eggs. 展开更多
关键词 Parchment-shelled eggs Rigid-shelled eggs Red-eared slider turtle Trachemys scripta Chinese threekeeled pond turtle Chinemys reevesii Embryo Environmental hormone
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利用Python语言的Turtle库绘制正多变形 被引量:3
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作者 林晓芬 《电脑知识与技术》 2020年第22期111-113,共3页
Python语言是目前最接近自然语言的通用编程语言,目前受关注度非常高,国内许多高校都开设了Python程序设计课程。Python语言的Turtle库是一个简单、易用的绘图库,可以用作Python语言学习的入门库。通过选取一些有趣的绘图案例,来增强学... Python语言是目前最接近自然语言的通用编程语言,目前受关注度非常高,国内许多高校都开设了Python程序设计课程。Python语言的Turtle库是一个简单、易用的绘图库,可以用作Python语言学习的入门库。通过选取一些有趣的绘图案例,来增强学生学习语言的兴趣。 展开更多
关键词 PYTHON语言 turtle
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Turtle海龟画图之螺旋线 被引量:2
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作者 林晓芬 《电脑知识与技术》 2020年第32期199-201,共3页
Python语言是目前最接近自然语言的通用编程语言,目前受关注度非常高,国内许多高校都开设了Python程序设计课程。Python语言的Turtle库是一个简单、易用的绘图库,可以用作Python语言学习的入门库。通过选取一些有趣的绘图案例,来增强学... Python语言是目前最接近自然语言的通用编程语言,目前受关注度非常高,国内许多高校都开设了Python程序设计课程。Python语言的Turtle库是一个简单、易用的绘图库,可以用作Python语言学习的入门库。通过选取一些有趣的绘图案例,来增强学生学习Python编程语言的兴趣。 展开更多
关键词 PYTHON语言 turtle
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Python语言的Turtle库简介
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作者 林晓芬 《电脑编程技巧与维护》 2022年第9期40-41,73,共3页
Python语言语法简洁、清晰、易读。学生在学习Python语言时,学习难度起点低,容易入门,国内许多高校都开设了Python程序设计课程。Python语言的Turtle库设计巧妙,作图模型简单强大。初学者很快能编写出趣味生动的作图程序,极大地提高了... Python语言语法简洁、清晰、易读。学生在学习Python语言时,学习难度起点低,容易入门,国内许多高校都开设了Python程序设计课程。Python语言的Turtle库设计巧妙,作图模型简单强大。初学者很快能编写出趣味生动的作图程序,极大地提高了学习者的兴趣和积极性。 展开更多
关键词 PYTHON语言 turtle
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Turtle before Turtles
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作者 LI Chun 《Bulletin of the Chinese Academy of Sciences》 2018年第4期247-249,共3页
People are familiar with modern turtles, but the evolution of turtles remains one of the biggest mysteries in paleontology. The turtle has a unique body form of tetrapods (four-leg vertebrates,or vertebrates except fi... People are familiar with modern turtles, but the evolution of turtles remains one of the biggest mysteries in paleontology. The turtle has a unique body form of tetrapods (four-leg vertebrates,or vertebrates except fishes, such as lizards/crocodiles,birds, and mammals). 展开更多
关键词 turtle BEFORE turtleS NATURE
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Captive Breeding of the Four-eyed Turtle(Sacalia quadriocellata) 被引量:2
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作者 HE Bin LIU Yuxiang +8 位作者 SHI Haitao ZHANG Jie HU Maogui MA Yonggang FU Lirong HONG Meiling WANG Jichao Fong J.Jonathan Parham F.James 《Asian Herpetological Research》 SCIE 2010年第2期111-117,共7页
In 1998,a study on forty-five four-eyed turtles(Sacalia quadriocellata) was initiated to gather preliminary biological data of this species and to investigate the feasibility of its captive reproduction.In the followi... In 1998,a study on forty-five four-eyed turtles(Sacalia quadriocellata) was initiated to gather preliminary biological data of this species and to investigate the feasibility of its captive reproduction.In the following six years,no courtship behavior was found occurring in males and no oviposition in females.From 2004 to 2007,two successful techniques were applied to initiate reproductive behavior:1) injecting exogenous reproductive hormones; and 2) reducing the stress of living in captivity.As a result of the hormone treatments,courtship behavior and copulation were observed during September and October,2005.However,no courtship displays were seen from the CK males,which were not treated with hormones.Ovulation occurred between December and March,and the correlation was not significant between behavior of ovulation and food intake.Females laid only one clutch of eggs each year,with 2.47 eggs(n=34,range=1–4) at average,and 84 eggs were totally obtained,of which 13 were damaged,52 were infertile and 19 fertile.Of the fertile eggs,nine were hatched with mean incubation period of 105.9 days(n=9,range=89–122 days) at temperature ranging from 24 to 27℃. 展开更多
关键词 four-eyed turtle Sacalia quadriocellata captive breeding HORMONE STRESS CONSERVATION
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Effects of Dietary Soy Protein Concentrate on Growth, Digestive Enzymes Activities and Target of Rapamycin Signaling Pathway Regulation in Juvenile Soft-Shelled Turtle, <i>Pelodiscus sinensis</i> 被引量:3
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作者 Fan Zhou Yaqin Wang +3 位作者 Li Tang Yong Huang Xueyan Ding Zhongyang He 《Agricultural Sciences》 2015年第3期335-345,共11页
Soft-shelled turtle, Pelodiscus sinensis is important aquatic species in China, and searching for alternatives protein resources to fish meal (FM)-based feeds in feed has become urgent and important for its sustainabi... Soft-shelled turtle, Pelodiscus sinensis is important aquatic species in China, and searching for alternatives protein resources to fish meal (FM)-based feeds in feed has become urgent and important for its sustainability development. The present study was conducted to assess the effects of dietary soy protein concentrate (SPC) on growth, digestive enzymes and target of rapamycin (TOR) signaling pathway of juvenile P. sinensis (4.56 ± 0.09 g). SPC was applied to replace FM protein at 0%, 15%, 30% and 60% (designated as T0, T15, T30 and T60, respectively), and each diet was fed to triplicate groups. The results showed that there was no significant difference in growth performance and feed utilization except of the turtles fed with T60 diet, of which showed poorer daily weight gain and feed conversion rate. The pepsin/trypsin and Na+-K+ ATP-ase activities decreased dramatically when SPC level increased, and lipase activities in liver and intestinal tract also showed decline tendency. However, amylase activities were unaffected. No significant differences were observed in TOR, S6K1 and 4E-BP1 genes mRNA expression level of TOR signaling pathway among the treatments. However, the relative phosphorylated level of these proteins decreased significantly when SPC level increased. The present study indicated that high SPC substitution level would suppress digestive enzymes and TOR signaling pathway proteins phosphorylated level and eventually result in growth reduction of P. sinensis. 展开更多
关键词 Soft-Shelled turtle P. sinensis SOY Protein Concentrate GROWTH Performance Digestive Enzymes Target of Rapamycin Signaling Pathway
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Structure and Function of the Gastrointestinal Tract of the Green Turtle(Chelonia mydas) Hatchling 被引量:1
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作者 Hualing CHEN Mingbin YE +3 位作者 Yuyan LU Jinxia DUAN Pipeng LI Hexiang GU 《Asian Herpetological Research》 SCIE CSCD 2015年第4期317-330,共14页
The gastrointestinal tracts of four Chelonia mydas hatchlings were examined at the anatomical, histological and ultrastructural level. Our results show that the gastrointestinal tract(GI) is composed by esophagus, s... The gastrointestinal tracts of four Chelonia mydas hatchlings were examined at the anatomical, histological and ultrastructural level. Our results show that the gastrointestinal tract(GI) is composed by esophagus, stomach, small intestine(SI) and large intestine(LI), and histologically of mucosa, submucosa, muscularis externa(ME) and serosa. The esophagus is marked by conical papillae lined by keratinized stratified squamous epithelium, whereas the remaining GI by simple columnar epithelium; esophageal diverticulum is absent. The stomach covered with mucous granule cells, contains cardia, fundic regions and pylorus, which are separately characterized by cardiac glands, fundic glands and pyloric glands, and have the thickest submucosa and ME of the GI. The ME of the esophagus mainly consist of one layer of circular smooth muscle whereas the rest of GI of two layers, inner circular muscle and outer longitudinal muscle. The SI is slightly longer than the LI and the GI is approximately 5.11 times of the carapace length. The SI is lined with longitudinal zigzag folds and characterized by absorptive cells with longer and denser microvilli, whereas the LI by transversal folds, goblet cells and lymphoid nodules. Only intestinal glands appear in duodenum. Endocrine cells are observed in all sections of the GI and accounted for the largest proportion in duodenum. The results demonstrate a perfect combination of the structure and function of the GI and reveal that the digestion and absorption primarily occurs in the foregut. C. mydas hatchling may prefer carnivorous diet. 展开更多
关键词 ANATOMY HISTOLOGY ULTRASTRUCTURE digestive tract DIET sea turtle
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基于Python-turtle库的程序设计图例教学法与实践 被引量:2
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作者 刘旭 马文彬 吴茜 《计算机教育》 2020年第3期101-104,108,共5页
针对目前程序设计类课程对控制结构的讲解存在的问题,分析根本原因,提出基于Pythonturtle库的程序设计图例教学法,列举顺序结构、选择结构和循环结构3种控制结构,阐述图例教学法的教学要点。
关键词 PYTHON语言 turtle 程序设计 控制语句
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The Effect of the Cyp19a1 Gene Methylation Modification on Temperature-dependent Sex Determination of Reeves' Turtle(Mauremys reevesii) 被引量:1
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作者 Wenxiu RU Liushuai HUA +6 位作者 Yufeng WEI Weiye LI Dainan CAO Yan GE Hong CHEN Xianyong LAN Shiping GONG 《Asian Herpetological Research》 SCIE CSCD 2017年第3期213-220,共8页
Temperature-dependent sex determination(TSD) is a type of environmental sex determination in which the sex of the embryos depends on the ambient temperature; however,the molecular mechanisms governing this process r... Temperature-dependent sex determination(TSD) is a type of environmental sex determination in which the sex of the embryos depends on the ambient temperature; however,the molecular mechanisms governing this process remain unknown.Aromatase,encoded by the cyp19a1 gene,which converts androgens into estrogens in animals,was considered to be the key gene for TSD.In this study,the 5'-flanking region of the cyp19a1 gene in Reeves' turtle(Mauremys reevesii) was cloned,and the promoter region was identified using the luciferase reporter assay.Then the eggs of Reeves' turtle were incubated at different temperatures(26°C: male-biased temperature; 29°C: non-sex-biased temperature and 32°C: female-biased temperature).During the thermosensitive period,the adrenal kidney gonad complexes(AKG) were sampled.DNA methylation analysis of the AKG samples showed that the promoter region of the cyp19a1 gene was significantly de-methylated in the female-biased temperature regime(P&lt;0.01).Quantitative analysis of the cyp19a1 gene and estrogen by q PCR and Elisa assay showed that the expression level of the cyp19a1 gene and estrogen content were both upregulated significantly at the female-biased temperature(P&lt;0.01).These results indicated that the de-methylation response of the cyp19a1 gene to incubation temperature,especially at the female-biased temperature,could lead to temperature-specific expression of aromatase and increased estrogen levels,which may further determine gonadal development in Reeves' turtle.These findings provide insights into the genetic mechanisms underlying TSD. 展开更多
关键词 Reeves' turtle Mauremys reevesii temperature-dependent sex determination (TSD) cyp19a1 gene methylation
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Green Turtle, <i>Chelonia mydas</i>, Nesting and Temperature Profile of the Nesting Beach at Huyong Island, the Similan Islands in Andaman Sea 被引量:1
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作者 Sarawoot Gomuttapong Winai Klom-In +3 位作者 Jirarach Kitana Putsatee Pariyanonth Kumthorn Thirakhupt Noppadon Kitana 《Natural Resources》 2013年第4期357-361,共5页
Global change in temperature is regarded as a serious natural disaster that may cause extinction of organisms. Green turtle, Chelonia mydas, is not only an endangered species but also a species with temperature depend... Global change in temperature is regarded as a serious natural disaster that may cause extinction of organisms. Green turtle, Chelonia mydas, is not only an endangered species but also a species with temperature dependent sex determination that could be affected by the global warming. In this study, nesting and temperature profile of C. mydas nesting beach at HuyongIsland, the most important nesting site of C. mydas in Andaman Sea of Thailand, were studied in order to monitor a potential effect of regional climate change on the green turtle nesting activity and habitat. Nesting activities were surveyed during May-August 2011 and temperature profiles of the nesting beach were monitored for 58 days during the normal incubation period of this species. The total of 25 nests with clutch size of 105 ± 25 eggs was found during this study period suggesting normal nesting activity of the green turtle. Temperature profile of the nesting beach showed similar trend among nests with no clear influence of the vegetation cover. Mean nest temperature at the middle-third period, corresponding to the temperature-sensitive period of C. mydas, ranged from 28.3°C to 28.9°C, suggesting a slightly male-biased sex ratio of the offspring. Overall, temperature profile of the nesting beach showed little or no indication of adverse effects of regional increase in temperature on nesting activity and egg incubation of the green turtle at this period. 展开更多
关键词 Conservation NESTING Ecology Sea turtle Thermal Profile
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Molecular Characterization and Expression Analysis of Matrix Metalloproteinase 3 in the Asian Yellow Pond Turtle Mauremys mutica 被引量:1
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作者 Mi ZHAO Yan SHI +4 位作者 Jian ZHAO Xinping ZHU Kunci CHEN Debo PAN Chengqing WEI 《Asian Herpetological Research》 SCIE 2014年第1期38-48,共11页
Matrix metallopeptidase 3 is a zinc-containing proteinase that participates in tissue remodeling and immune responses. In this study, a cDNA encoding matrix metallopeptidase 3 was isolated and characterized from the A... Matrix metallopeptidase 3 is a zinc-containing proteinase that participates in tissue remodeling and immune responses. In this study, a cDNA encoding matrix metallopeptidase 3 was isolated and characterized from the Asian yellow pond turtle Mauremys mutica(designated as MaMMP3). The MaMMP3 cDNA is 1805 bp and consists of a 5'-untranslated region(UTR) of 56 bp, a 3'-UTR of 243 bp, and an open reading frame(ORF) of 1506 bp encoding 481 amino acids. Homology analysis of MaMMP3 revealed that the MaMMP3 shared 25%–63% similarity to other known MMP3 sequences. The genomic sequence covers 6007 bp. Comparative analysis of the cDNA sequence revealed that the Asian yellow pond turtle MMP3 has eight exons and seven introns. The phylogenetic tree showed that the MaMMP3 is closely related to Gallus gallus MMP3 and Taeniopygia guttata MMP3. The mRNA expression of the MaMMP3 in normal group without any bacterial challenge could be detected in all studied tissues including kidney, heart, live and spleen, with the highest level in the spleen. The results of immune challenge showed that the expression level of MaMMP3 was up-regulated in the spleen and liver. These results provided an important information for studying the roles of Asian yellow pond turtle MMP3 in immunity further. 展开更多
关键词 Asian yellow pond turtle Mauremys mutica Serratia marcescens Matrix metallopeptidase 3 Immune responses
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以Turtle入手的程序设计教学案例设计与实践 被引量:2
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作者 林卫中 《现代计算机》 2021年第19期162-165,共4页
《计算机程序设计》课程是计算机学科的专业基础课程,对学生专业课程学习有重要影响,理解和掌握程序结构和函数是该课程的主要教学目的。在Python语言框架下,利用Turtle库绘制图形进行程序设计的教学相比较传统C或Java语言具有极大的优... 《计算机程序设计》课程是计算机学科的专业基础课程,对学生专业课程学习有重要影响,理解和掌握程序结构和函数是该课程的主要教学目的。在Python语言框架下,利用Turtle库绘制图形进行程序设计的教学相比较传统C或Java语言具有极大的优势。教学实践表明Turtle绘图显著激发学生学习程序设计的兴趣,使学习的中心从繁琐的语法转移到程序设计问题本身,取得良好的教学效果。 展开更多
关键词 PYTHON语言 教学案例 turtle绘图 程序设计
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Physiological responses in vitamin C system during hibernation in juvenile Chinese soft-shelled turtle Pelodiscus sinensis
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作者 CHEN Bojian NIU Cuijuan +1 位作者 YUAN Lin ZHANG Wenyi 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第2期767-776,I0001-I0011,共11页
Vitamin C (Vc) is an important antioxidant that helps turtles tolerating stressful environment. This work quantified changes in tissue Vc levels during winter hibernation in the soft-shelled turtle Pelodiscus sinensis... Vitamin C (Vc) is an important antioxidant that helps turtles tolerating stressful environment. This work quantified changes in tissue Vc levels during winter hibernation in the soft-shelled turtle Pelodiscus sinensis , to reveal the stress response pattern of tissue Vc during hibernation and contribute basic data for turtle culture. We sampled juvenile soft-shelled turtles at pre-hibernation (17.0°C mud temperature;MT), during hibernation (5.8°C MT) and after arousal (20.1°C MT) in the field. The transcript levels of the gene encoding L-gulonolactone oxidase (GLO), the key enzyme for Vc synthesis, decreased significantly during hibernation. However, GLO activity did not match the GLO transcription patterns and remained stable during hibernation, and showed temperature-dependent kinetic characteristics. Vitamin C levels in the brain, liver, kidney, and spleen (but not muscle) all decreased significantly during hibernation, but recovered to pre-hibernation levels or even higher levels after arousal. The soft-shelled turtle endured 5 months of hibernation with no significant oxidative damage in most tissues, except in the spleen. Splenic Vc was nearly exhausted during hibernation, accompanied by a significantly elevated malonaldehyde (MDA) level. Although the high level of oxidative damage quickly decreased after arousal, the potential tissue damage in the spleen during hibernation might account for the weakened immune capacity of turtles after hibernation. 展开更多
关键词 CHINESE soft-shelled turtle HIBERNATION reactive oxygen species (ROS) L-gulonolactone OXIDASE oxidative stress
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Microstructure and mechanical property of turtle shell 被引量:1
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作者 Wei Zhang Chengwei Wu +1 位作者 Chenzhao Zhang Zhen Chen 《Theoretical & Applied Mechanics Letters》 2012年第1期44-48,共5页
The turtle shell is an amazing structure optimized through the long-term evolution by nature. This paper reports the experimental study on the mechanical property at different levels and locations, and the microstruct... The turtle shell is an amazing structure optimized through the long-term evolution by nature. This paper reports the experimental study on the mechanical property at different levels and locations, and the microstructure of the shell from Trachemys scripta (Red-ear turtle) living in South China. 展开更多
关键词 mechanical property turtle shell MICROSTRUCTURE
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Effect of Incubation Temperature on the Somatic Development of the Snail-Eating Turtle Malayemys macrocephala
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作者 Rangsima PEWPHONG Jirarach KITANA Noppadon KITANA 《Asian Herpetological Research》 SCIE 2013年第4期254-262,共9页
The rising average global temperature can lead to changes both in the physical and biological environments and affect the survival of organisms. Freshwater turtles are considered to be susceptible species since their ... The rising average global temperature can lead to changes both in the physical and biological environments and affect the survival of organisms. Freshwater turtles are considered to be susceptible species since their development is dependent on incubation temperature. In Thailand, although several species of freshwater turtle are present, the extent of their susceptibility to temperature change is unknown due to the lack of information on their developmental patterns. This research, therefore, is aimed at examining the effects of temperature on somatic development in Malayemys macrocephala, a native species and the most common freshwater turtle in Thailand. Turtle eggs were collected from rice fields in the central part of Thailand during December 2011 to February 2012 inclusive. Eggs (237-238 per condition) were incubated in microprocessor-controlled incubators at three different temperatures (26 ℃, 29℃ and 32℃) with a relative humidity in excess of 80%. Each week, until the remaining eggs hatched, eggs were randomly selected, removed and dissected to reveal the developing embryo to screen for developmental stage and any abnormalities. The incubation period (lay to hatch) was not significantly different among the three temperatures (115 ±11.3 d, 115 ±20.3 d and 109±17.8 d, respectively), but the growth patterns, as indicated by the stages of development and carapace lengths, were significantly different. At a high temperature (32℃), turtle embryos showed a significantly faster growth rate than at the intermediate and low temperatures (29 ℃and 26 ℃), but had a significantly (over 3.3-fold) higher incidence of developmental abnormalities (especially deformed bodies) than at the lower temperatures. Overall, the results indicate that incubation temperature is an important variable affecting the somatic development of this tropical freshwater turtle species, whilst abnormalities in the embryonic body may be a sensitive indicator of extreme thermal stress. 展开更多
关键词 ABNORMALITY egg incubation embryonic stage freshwater turtle growth
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