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Morphological Characterization and Hydrodynamic Behavior of Shortfin Mako shark(Isurus oxyrinchus)Dorsal Fin Denticles

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Journal of Bionic Engineering 2019年第4期16卷 730-741页

作者： Fernandez-Waid Patricia Diez Guzman Bidaguren Inigo Izagirre Urtzi Blanco Jesus Maria Soto Manu Department of Zoology and Animal Cell Biology Research Centre for Experimental Marine Biology and Biotechnology(PiE-UP V/EHU)University of the Basque CountryBilbao and Areatza z/gPlentzia 48620BizkaiaSpain Marine Research Division AZTITxatxarramendi s/n Sukarrieta 48395BizkaiaSpain Department of Nuclear Engineering and Fluid Mechanics School of Engineering(UP V/EHU)University of the Basque CountryPlaza lngeniero Torres Quevedo 148013 BilbaoBizkaiaSpain

The shortfin mako shark(Isurus oxyrinchus)is one of the fastest marine fishes,reaching speeds of up to 70 km·h^-*** speed is related to the skin surface design composed of dermal *** vary in size and shape according to placement on the body and minimize turbulence around the *** objective of this study is to analyze the interaction between seawater flow and denticles on the dorsal ***-resolution microscopy(scanning electron microscopy and confocal microscopy)were used to measure defined parts of the dermal *** measurements,along with ratios based on length-to-width define three morphologies(rounded,semi-rounded,long)that were 3D *** fluid dynamics simulated fluid passage over reconstructed denticles and describe hy-drodynamic efficiency under different *** increase in angle of inclination produced a relevant increase in the drag coefficient,especially for high velocity *** lowest drag coefficient values were found in long and semi-rounded,followed by rounded *** hydrodynamic behavior of shark skin demonstrates a relation to the morphological characteristics of dermal denticles on the dorsal *** is concluded that the best hydroefficiency relies on the rounded morphology and may serve to design hydrodynamically efficient surfaces or manmade assemblies.

关键词： denticles hydrodynamic mako shark computational fluid dynamics

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Study on the micro-replication of shark skin

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Science China(Technological Sciences) 2008年第7期51卷 890-896页

作者： HAN Xin ZHANG DeYuan School of Mechanical Engineering and Automation Beihang UniversityBeijing 100083China

Direct replication of creatural scarfskins to form biomimetic surfaces with relatively vivid morphology is a new attempt of the bio-replicated forming technology at animal body. Taking shark skins as the replication templates, and the micro-embossing and micro-molding as the material forming methods, the micro-replicating technology of the outward morphology on shark skins was demonstrated. The preliminary analysis on replication precision indicates that the bio-replicated forming technology can replicate the outward morphology of the shark scales with good precision, which validates the application of the bio-replicated forming technology in the direct morphology replication of the firm creatural scarfskins.

关键词： shark skin biomimetic surface bio-replicated forming micro-replication

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Beneficial effects of a novel shark-skin collagen dressing for the promotion of seawater immersion wound healing

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Military Medical Research 2018年第2期5卷 117-128页

作者： Xian-Rong Shen Xiu-Li Chen Hai-Xia Xie Ying He Wei Chen Qun Luo Wei-Hong Yuan Xue Tang Deng-Yong Hou Ding-Wen Jiang Qing-Rong Wang The PLA Key Laboratory of Biological Effect and Medical Protection on Naval Vessel Special Environment Naval Medical Research InstituteShanghai 200433China College of Food Science and Technology Shanghai Ocean UniversityShanghai 201306China Research Center of TCM Processing Technology Zhejiang Chinese Medical UniversityHang Zhou 311401China

Background: Wounded personnel who work at sea often encounter a plethora of difficulties. The most important of these difficulties is seawater immersion. Common medical dressings have little effect when the affected area is immersed in seawater, and only rarely dressings have been reported for the treatment of seawater-immersed wounds. The objective of this study is to develop a new dressing which should be suitable to prevent the wound from seawater immersion and to promote the wound ***: shark skin collagen(SSC) was purified via ethanol de-sugaring and de-pigmentation and adjusted for p H. A shark skin collagen sponge(SSCS) was prepared by freeze-drying. SSCS was attached to an anti-seawater immersion polyurethane(PU) film(SSCS+PU) to compose a new dressing. The biochemical properties of SSC and physicochemical properties of SSCS were assessed by standard methods. The effects of SSCS and SSCS+PU on the healing of seawaterimmersed wounds were studied using a seawater immersion rat model. For the detection of SSCS effects on seawaterimmersed wounds, 12 SD rats, with four wounds created in each rat, were divided into four groups: the 3 rd day group, 5 th day group, 7 th day group and 12 th day group. In each group, six wounds were treated with SSCS, three wounds treated with chitosan served as the positive control, and three wounds treated with gauze served as the negative control. For the detection of the SSCS+PU effects on seawater-immersed wounds, 36 SD rats were divided into three groups: the gauze(GZ)+PU group, chitosan(CS)+PU group and SSCS+PU group, with 12 rats in each group, and two wounds in each rat. The wound sizes were measured to calculate the healing rate, and histomorphology and the immunohistochemistry of the CD31 and TGF-β expression levels in the wounded tissues were measured by standard ***: The results of Ultraviolet-visible(UV-vis) spectrum, Fourier-transform infrared(FTIR) spectrum, circular dichroism(CD) spectra, sodium

关键词： Anti-seawater immersion dressing shark skin collagen Seawater immersion wound Wound healing

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shark mouth pancreaticojejunostomy: a new enteric reconstruction procedure of pancreatic stump

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Chinese Medical Journal 2019年第11期132卷 1354-1358页

作者： Hang-Yan Wang Mu-Xing Li Dian-Rong Xiu Department of General Surgery Peking University Third Hospital Beijing 100191 China

Background:The enteric reconstruction procedure of pancreatic stump after pancreaticoduodenectomy remains to be the critical factor influencing the mortality and *** widely accepted surgical procedure for the pancreaticojejunostomy has been erected *** have developed a new technique of pancreaticojejunostomy named "shark mouth pancreaticojejunostomy." The aim of this study is to assess the efficacy of "shark mouth pancreaticojejunostomy."Methods:This is a prospective single-arm observational study to evaluate the clinical efficacy of "shark mouth pancreaticojejunostomy." Patients with diseases,in whom a pancreaticoduodenectomy is indicated,would be recruited from Peking University Third *** hypothesis to be tested is that a "shark mouth pancreaticojejunostomy" will reduce fistula rate from around 20% to less than 10%.A sample size of 120 patients will be *** primary endpoint is the incidence rate of postoperative pancreatic fistula (POPF).The secondary endpoints of the study are anastomosis time,postoperative hospital stay,and morbidities besides the POPF such as the *** patients will undergo pancreaticoduodenectomy and be followed up for 3 *** relevant data will be monitored and ***:The current trial will explore the therapeutic value of the newly raised pancreaticojejunostomy procedure as the "shark mouth pancreaticojejunostomy." Its theoretical base and pragmatic feature will promise high external *** registration:Clinical ***:NCT03366038;https://***.

关键词： shark mouth pancreaticojejunostomy Efficacy Safety Pancreaticoduodenectomy

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基于数字化反应堆物理计算程序shark的一步法输运计算方法研究

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核动力工程 2023年第4期44卷 33-40页

作者：赵晨赵文博张宏博王博陈长彭星杰宫兆虎曾未李庆中国核动力研究设计院核反应堆系统设计技术重点实验室成都610213

为建立基于数字化反应堆技术的新一代反应堆物理计算方法,实现数字化反应堆高保真建模、高分辨率高精度计算,基于数字化反应堆物理计算程序shark,开展了一步法输运计算方法研究,建立并比较了二维/一维方法及准三维特征线输运方法;基于... 详细信息

为建立基于数字化反应堆技术的新一代反应堆物理计算方法,实现数字化反应堆高保真建模、高分辨率高精度计算,基于数字化反应堆物理计算程序shark,开展了一步法输运计算方法研究,建立并比较了二维/一维方法及准三维特征线输运方法;基于空间区域分解及粗网有限差分(CMFD)的大规模并行加速技术,实现了棒状堆芯及板状堆芯的全堆规模一步法输运计算。数值结果与蒙特卡罗程序基准解相比,特征值偏差小于100pcm(1pcm=10^(-5)),最大棒功率、板功率偏差小于3%,验证了shark程序一步法输运计算方法具有良好计算精度,能够适用于棒状、板状堆芯等多应用场景。

关键词：数字化反应堆二维/一维方法准三维特征线方法 shark

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shark Cognition and a Human Mediated Driver of a Spate of shark Attacks

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Open Journal of Animal Sciences 2014年第5期4卷 263-269页

作者： Marie Levine Ralph S. Collier Erich Ritter Moustafa Fouda Vincent Canabal shark Research Institute Princeton USA Global shark Attack File Princeton USA shark Research Committee Chatsworth USA Nature Conservation Sector Egyptian Environmental Affairs Agency Cairo Egypt

Five unprovoked shark attacks are reported from Sharm-El-Sheikh, Egypt, between 30 November and 5 December 2010. Three of the five attacks are attributed to an oceanic whitetip shark, Carcharinus longimanus with a distinctive crescent-shaped notch in the upper lobe of the caudal fin. The shark was observed during the first attack on a snorkeler and photographed underwater during the second shark attack on a swimmer. In a video taken several months prior to the attacks, the same shark is hand-fed underwater by a divemaster with additional fish in a pack over his buttock. The shark can be seen swimming behind the divemaster while he removed additional fish from this pack. In Victims 1, 2 and 5, the shark removed an extensive amount of tissue from the victims’ buttock. The three victims also lost a hand and/or a portion of their forearm, suggesting the injuries were inflicted by a shark conditioned to associating food with hand-feedings and the human form. The remaining two attacks, Cases 3 and 4, were attributable to the shortfin mako shark, Isurus oxyrinchus. This was determined from a unique dental pattern of the right side of the upper jaw due to a prior injury. This same “misalignment” dental pattern was observed in the injuries sustained by Victims 3 and 4. We conclude that the shortfin mako shark was responsible for the attacks on Victims 3 and 4, and the oceanic whitetip shark was the causal species of attacks on Victims 1, 2, and 5.

关键词： Forensic Science Red Sea sharks shark Attack shark Cognition

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基于shark-Hartmann理论的波前探测技术研究

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应用光学 2014年第5期35卷 823-829页

作者：郭广妍樊仲维余锦葛文琦康治军唐熊忻貊泽强王昊成石朝辉中国科学院光电研究院北京100094 中国科学院大学北京100049 中国国科世纪激光技术有限公司北京102211

精确的波前探测是反射镜面型检测及光束波前畸变测量的重要依据,论文根据sharkHartmann理论对波前探测技术进行了模拟和实验研究。将平行光经过球面透镜/柱面透镜后形成的球面波/柱面波作为探测波前。实验采用商用的微透镜阵列和CCD搭建... 详细信息

精确的波前探测是反射镜面型检测及光束波前畸变测量的重要依据,论文根据sharkHartmann理论对波前探测技术进行了模拟和实验研究。将平行光经过球面透镜/柱面透镜后形成的球面波/柱面波作为探测波前。实验采用商用的微透镜阵列和CCD搭建shark-Hartmann传感器,利用实际光束作为参考光,避免了参考光的不准直性对实验的影响。模拟计算结果表明平均曲率误差为13.423mm,实验结果实现了对球面/柱面/倾斜波的探测及复原。

关键词：自适应光学 shark Hartmann传感器波前重构 Zernike多项式

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On the Separation Mechanism between a shark’s Tooth and Its Jaw Base, with Special Emphasis on an Observation Made from a White shark, <i>Carcharodon carcharias</i>

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Open Journal of Animal Sciences 2018年第3期8卷 329-334页

作者： Erich K. Ritter Andreas Dellios Department of Mathematics & Statistics University of West Florida Pensacola FL USA shark Research Institute Global shark Attack File Princeton NJ USA shark School 5970 Osprey Place Pensacola FL USA

Feeding is the likely cause for tooth shedding in sharks. Although the overall process of loosing teeth has been well studied, hardly any emphasis has been given to the actual separation mechanism between a shark’s tooth base and the surrounding jaw tissue. Attention is given to this very process, in connection to a never before videotaped tooth loss of a white shark, Carcharodon carcharias, that occurred within 0.3 seconds. Since the shark did not bite into anything prior to this observation, the cause for this tooth loss does not seem feeding but fatigue related, triggered through a combination of mechanical and potentially biochemical degradation processes.

关键词： shark Tooth Loss Tooth Shedding White shark

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Is the shark Just Drifting, or Does It Take a Quick Nap?

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Open Journal of Animal Sciences 2020年第1期10卷 40-47页

作者： Erich K. Ritter Department of Mathematics and Statistics University of West Florida Pensacola FL USA shark Research Institute Princeton NJ USA

It is unknown if resting sharks can sleep, which is also true for gliding ones. Here, a videotaped bull shark is presented that drifted in an uncontrolled manner for 120 seconds while sinking with 0.1 m/second. Several aspects are discussed to determine if the shown behavior reflects the commonly accepted definition of sleep. Additionally, the idea is also discussed if this state might reflect a “quiet waking state” instead of where the shark still maintained some vigilance despite its general appearance.

关键词： Drifting Melatonin Pineal Gland shark Sleep

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Circling the Blood in the Water: The Difficulties in Endangered Species Protections for the Great White shark

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Natural Resources 2014年第11期5卷 666-680页

作者： Derek Julio S.J. Quinney College of Law Salt Lake City USA

The purpose of legislation like the Endangered Species Act is to provide a means to conserve the ecosystems of endangered and threatened species, but not all species that may appear to need conservation are granted protection. An estimated 100 million sharks are killed each year largely due to exploitation, yet few shark species are ever granted protection under state or federal endangered species acts. The Northeastern Pacific population of the Great White shark is no exception. Despite the numerous threats facing the white shark, NOAA denied a petition to list it as an endangered or threatened species under the federal Endangered Species Act. In light of the pending California decision to list the white shark under its state endangered species act, this paper considers whether or not such extreme protections are necessary. This paper first discusses the threats facing the white shark, the listing processes of both the federal and the California endangered species acts, and NOAA’s 12-month negative finding. Finally, this paper concludes that endangered species protections are not warranted in the case of the Northeastern Pacific white shark because of prior government intervention and conservation efforts already in place.

关键词： Endangered Species Act ESA CESA California Endangered Species Act Great White shark

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