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Zoological Research 2018年第6期39卷 413-423页

作者： Lorenzo Alibardi Comparative Histolab Padua Department of BiologyUniversity of Bologna

Lizards are key amniote models for studying organ regeneration. During tail regeneration in lizards, blastemas contain sparse granulocytes, macrophages, and lymphocytes among the prevalent mesenchymal cells. Using transmission electron microscopy to examine scarring blastemas after third and fourth sequential tail amputations, the number of granulocytes, macrophages, and lymphocytes increased at 3-4 weeks in comparison to the first regeneration. An increase in granulocytes and agranulocytes also occurred within a week after blastema cauterization during the process of scarring Blood at the third and fourth regeneration also showed a significant increase in white blood cells compared with that under normal conditions and at the first regeneration. The extracellular matrix of the scarring blastema, especially after cauterization, was denser than that in the normal blastema and numerous white blood cells and fibroblasts were surrounded by electron-pale, fine fibrinoid material mixed with variable collagen fibrils. In addition to previous studies, the present observations support the hypothesis that an increase in inflammation and immune reactions determine scarring rather than regeneration. These new findings verify that an immune reaction against mesenchymal and epidermal cells of the regenerative blastema is one of the main causes for the failure of organ regeneration in amniotes.

关键词： Lizard tail Repetitive regeneration Blood Immune cells Ultrastructure

tail asymptotic for discounted aggregate claims with one-sided linear dependence and general investment return

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Science China Mathematics 2019年第4期62卷 735-750页

作者： Fenglong Guo Dingcheng Wang Jiangsu Key Laboratory of Financial Engineering and School of Finance Nanjing Audit University School of Mathematical Sciences University of Electronic Science and Technology of China

In this study, we investigate the tail probability of the discounted aggregate claim sizes in a dependent risk model. In this model, the claim sizes are observed to follow a one-sided linear process with independent and identically distributed innovations. Investment return is described as a general stochastic process with c`adl`ag paths. In the case of heavy-tailed innovation distributions, we are able to derive some asymptotic estimates for tail probability and to provide some asymptotic upper bounds to improve the applicability of our study.

关键词： Poisson risk model tail probability one-sided linear process heavy-tailed distribution asymptotic upper bound investment return

Re-evaluation of thyroid hormone signaling antagonism of tetrabromobisphenol A for validating the T3-induced Xenopus metamorphosis assay

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Journal of Environmental Sciences 2017年第2期29卷 325-332页

作者： Yao Wang Yuanyuan Li Zhanfen Qin Wuji Wei College of Environment Nanjing University of TechnologyNanjing 211816China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-environmental SciencesChinese Academy of SciencesBeijing I0008SChina University of Chinese Academy of Sciences Beijing 100049China

We developed the T3-induced Xenopus metamorphosis assay, which is supposed to be able to sensitively detect thyroid hormone（TH） signaling disruption of chemicals. The present study aimed to validate the T3-induced Xenopus metamorphosis assay by re-evaluating the TH signaling antagonism of tetrabromobisphenol A（TBBPA）, a known TH signaling disruptor. According to the assay we developed, Xenopus tadpoles at stage 52 were exposed to 10–500 nmol/L TBBPA in the presence of 1 nmol/L T3. After 96 hr of exposure, TBBPA in the range of 10–500 nmol/L was found to significantly inhibit T3-induced morphological changes of Xenopus tadpoles in a concentration-dependent manner in term of body weight and four morphological endpoints including head area（HA）, mouth width（MW）, unilateral brain width/brain length（ULBW/BL）, and hind-limb length/snout-vent length（HLL/SVL）.The results show that these endpoints we developed are sensitive for characterizing the antagonistic effects of TBBPA on T3-induced metamorphosis. Following a 24-hr exposure,we found that TBBPA antagonized expression of T3-induced TH-response genes in the tail,which is consistent with previous findings in the intestine. We propose that the tail can be used as an alternative tissue to the intestine for examining molecular endpoints for evaluating TH signaling disruption. In conclusion, our results demonstrate that the T3-induced Xenopus metamorphosis assay we developed is an ideal in vivo assay for detecting TH signaling disruption.

关键词： Thyroid hormone signaling Tetrabromobisphenol A Xenopus metamorphosis T3 induction tail

tail dependence of random variables from ARCH and heavy-tailed bilinear models

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Science China Mathematics 2002年第6期45卷 749-760页

作者：潘家柱 Department of Financial Mathematics School of Mathematical Sciences Peking University Beijing 100871 China

Discussed in this paper is the dependent structure in the tails of distributions of random variables from some heavy-tailed stationary nonlinear time series. One class of models discussed is the first-order autoregressive conditional heteroscedastic (ARCH) process introduced by Engle (1982). The other class is the simple first-order bilinear models driven by heavy-tailed innovations. We give some explicit formulas for the asymptotic values of conditional probabilities used for measuring the tail dependence between two random variables from these models. Our results have significant meanings in finance.

关键词： ARCH, bilinear model, dependence, tail probability.

Experimental manipulation of size and shape of tail spots and sexual selection in barn swallows

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Current Zoology 2017年第5期63卷 569-572页

作者： Anders P. MOLLER Ecologie Systematique Evolution CNRS Universite Paris-Sud AgroParisTech Universite Paris-Saclay 0rsayF-91400 France

Barn swallows Hirundo rustica have white spots on their tail feathers, and they have been hypothe-sized to be a handicap because white spots are prone to feather breakage, ectoparasites are dispro-portionately common in white spots, and size of white spots increases with tail length. Here I testfor attractiveness of narrow and long tail spots by manipulation of their shape while using com-plete painting of spots and an absence of treatment as a control. Female barn swallows are knownto differentially invest in reproduction when mated to attractive males. Spot manipulation tookplace during laying of the first clutch, and there were no effects of treatment on clutch size or broodsize of first or second broods. In contrast, the incidence of second clutches and the total number ofeggs and fledglings produced during the breeding season was larger in males with painting of theside of tail spots rather than painting of the tip of spots, painting of entire spots, or no treatment.These findings are consistent with the hypothesis that it is the shape rather than the size of tailspots that affects differential reproductive effort by female barn swallows.

关键词： Hirundo rustica, reliable signals, shape of tail spots, tail spots.

Labeled Network Stack: A High-Concurrency and Low-tail Latency Cloud Server Framework for Massive IoT Devices

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Journal of Computer Science & Technology 2020年第1期35卷 179-193页

作者： Wen-Li Zhang Ke Liu Yi-Fan Shen Ya-Zhu Lan Hui Song Ming-Yu Chen Yuan-Fei Chen State Key Laboratory of Computer Architecture Institute of Computing TechnologyChinese Academy of Sciences Beijing 100190China University of Chinese Academy of Sciences Beijing 100049China Peng Cheng Laboratory Shenzhen 518000China Zhongke Zhicheng Electronic Technology Company Limited Jining 272000China

Internet of Things(IoT)applications have massive client connections to cloud servers,and the number of networked IoT devices is remarkably increasing.IoT services require both low-tail latency and high concurrency in datacenters.This study aims to determine whether an order of magnitude improvement is possible in tail latency and concurrency in mainstream systems by proposing a hardware-software codesigned labeled network stack(LNS)for future datacenters.The key innovation is a cross-layered payload labeling mechanism that distinguishes different requests by payload across the full network stack,including application,TCP/IP,and Ethernet layers.This type of design enables prioritized data packet processing and forwarding along the full datapath,such that latency-insensitive requests cannot significantly interfere with high-priority requests.We build a prototype datacenter server to evaluate the LNS design against a commercial X86 server and the mTCP research,using a cloud-supported IoT application scenario.Experimental results show that the LNS design can provide an order of magnitude improvement in tail latency and concurrency.A single datacenter server node can support over 2 million concurrent long-living connections for IoT devices as a 99-percentile tail latency of 50 ms is maintained.In addition,the hardware-software codesign approach remarkably reduces the labeling and prioritization overhead and constrains the interference of high-priority requests to low-priority requests.

关键词： tail latency high concurrency network stack cloud server Internet of Things(IoT)service

Pancreatic stents for the prevention of post-endoscopic retrograde cholangiopancreatography pancreatitis should be inserted up to the pancreatic body or tail

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World Journal of Gastroenterology 2018年第22期24卷 2392-2399页

作者： Mitsuru Sugimoto Tadayuki Takagi Rei Suzuki Naoki Konno Hiroyuki Asama Yuki Sato Hiroki Irie Ko Watanabe Jun Nakamura Hitomi Kikuchi Yuichi Waragai Mika Takasumi Takuto Hikichi Hiromasa Ohira Department of Gastroenterology School of Medicine Fukushima Medical University Department of Endoscopy Fukushima Medical University Hospital

AIM To investigate the location to which a pancreatic stent should be inserted to prevent post-endoscopic retrograde cholangiopancreatography(ERCP) pancreatitis(PEP).METHODS Over a ten-year period at our hospital, 296 patients underwent their first ERCP procedure and had a pancreatic stent inserted; this study included 147 patients who had ERCP performed primarily for biliary investigation and had a pancreatic stent inserted to prevent PEP. We dividedthese patients into two groups: 131 patients with a stent inserted into the pancreatic head(head group) and 16 patients with a stent inserted up to the pancreatic body or tail(body/tail group). Patient characteristics and ERCP factors were compared between the groups.RESULTS Pancreatic amylase isoenzyme(p-AMY) levels in the head group were significantly higher than those in the body/tail group [138.5(7.0-2086) vs 78.5(5.0-1266.5), P = 0.03] [median(range)]. No cases of PEP were detected in the body/tail group [head group, 12(9.2%)]. Of the risk factors for post-ERCP hyperamylasemia(≥ p-AMY median, 131 IU/L), procedure time ≥ 60 min [odds ratio(OR) 2.65, 95%CI: 1.17-6.02, P = 0.02) and stent insertion into the pancreatic head(OR 3.80, 95%CI: 1.12-12.9, P = 0.03) were identified as independent risk factors by multivariate analysis.CONCLUSION Stent insertion up to the pancreatic body or tail reduces the risk of post-ERCP hyperamylasemia and may reduce the risk of PEP.

关键词： Pancreatic stent Endoscopic retrograde cholangiopancreatography Post-endoscopic retrograde cholangiopancreatography pancreatitis Post-endoscopic retrograde cholangiopancreatography hyperamylasemia Pancreatic body or tail

A Bio-Inspired Hopping Kangaroo Robot with an Active tail

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Journal of Bionic Engineering 2014年第4期11卷 541-555页

作者： Guan-Horng Liu Hou-Yi Lin Huai-Yu Lin Shao-Tuan Chen Pei-Chun Lin Department of Mechanical Engineering National Taiwan University Taipei 106 Taiwan

Inspired by kangaroo＇s locomotion, we report on developing a kangaroo-style hopping robot. Unlike bipeds, quadrupeds, or hexapods which altemate the legs for forward locomotion, the kangaroo uses both legs synchronously and generates the forward locomotion by continuous hopping behavior, and the tail actively balances the unwanted angular momentum generated by the leg motion. In this work, we generate the Center of Mass （CoM） locomotion of the robot based on the reduced-order Rolling Spring Loaded Inverted Pendulum （R-SLIP） model, for matching the dynamic behavior of the empirical robot legs. In order to compensate the possible body pitch variation, the robot is equipped with an active tail for pitch variation compensation, emulating the balance mechanism of a kangaroo. The robot is empirically built, and various design issues and strategies are addressed. Finally, the experimental evaluation is executed to validate the performance of the kangaroo-style robot with hopping locomotion.

关键词： legged robot kangaroo hopping SLIP tail

The movement dynamics of autotomized lizards and their tails reveal functional costs of caudal autotomy

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Integrative Zoology 2020年第6期15卷 511-521页

作者： Irene FERNÁNDEZ-RODRÍGUEZ Florentino BRAÑA Department of Organisms and Systems Biology(Zoology) University of OviedoOviedoSpain Research Unit of Biodiversity(UMIB UO/CSIC/PA)University of OviedoMieresSpain

Autotomy has evolved independently several times in different animal lineages.It frequently involves immediate functional costs,so regeneration evolved in many instances to restore the functionality of that body part.Caudal autotomy is a widespread antipredator strategy in lizards,although it may affect energy storage,locomotion dynamics,or survival in future encounters with predators.Here,we assessed the effect of tail loss on the locomotor performance of wall lizards(Podarcis muralis),as well as the recovery of locomotor functionality of lizards with regenerated tails,and the movement dynamics of shed tails that were either intact or having regenerated portions.tail loss had no effect on locomotion over unhindered spaces,possibly due to compensation between a negative effect on the stride of front limbs,and a positive effect of losing mass and friction force.We found a clear negative impact of tail loss on locomotion in spaces with interspersed obstacles,in which tailed lizards jumped larger distances when leaving the obstacles.Besides,lizards that used the tail to push off the ground were able to approach the obstacles from further,so that the tail seemed to be useful when used during jumping.Regeneration fully restores lizard’s locomotor capacities,but tail antipredator value,as indicated by the intensity of post-autotomic movements,is only partially retrieved.From these results,we propose that,together with the recovery of post-autotomy antipredator capacities,the restoration of the organismal locomotor performance may have been an important,yet frequently neglected factor in the evolution of lizard’s regeneration ability.

关键词： autotomy locomotor performance regeneration tail wall lizard

Vee-tail conceptual design criteria for commercial transport aeroplanes

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Chinese Journal of Aeronautics 2019年第3期32卷 595-610页

作者： Alejandro SANCHEZ-CARMONA Cristina CUERNO-REJADO Faculty of Aerospace Engineering Department of Aircraft and Spacecraft Technical University of Madrid (Universidad Poltécnica de Madrid)

Vee-tail configuration is an unconventional tail configuration for commercial transport aviation, the use of which could suppose reductions on CO2 emissions. The conceptual design criteria have been selected inspired on the certification requirements established by the aviation regulation in force. They are static stability in cruise, control after Critical Engine Failure(CEF),control in crosswind landing, and trim in these three conditions. The study is carried out through a combination of semi-empirical techniques and Vortex-Lattice Methods(VLM) and thus this analyses the consequences of applying these criteria to a reference aeroplane substituting its conventional tail by a parametrised Vee-tail configuration. The Vee-tail is defined by four parameters:span, root chord, taper ratio and dihedral angle. The results of the study establish a relation between the parameters in order to accomplish the proposed conceptual design criteria. To sum up, minimum and maximum limits are obtained for dihedral angle depending on the combination of the rest of parameters. In addition, a design restriction to the yawing trailing-edge tail control is reached when the results are analysed, demonstrating that its minimum size must be between 60%and 80% of the half-span of the tail, depending on the Vee-tail geometry.

关键词： Commercial transport aeroplane Conceptual aircraft design tail design requirements Unconventional tail design Vee-tail