具有环境适应能力的蛇形机器人仿生控制方法

基于生物学原理,本文构建了一种能够产生蛇形机器人多种仿生步态的多模态中枢模式发生器模型.该模型通过外部激励的引入,可以实现蛇形机器人运动形式的自由调整和转换,有助于提高蛇形机器人的环境适应能力.文中主要针对任意节数的多模态中枢模式发生器模型的稳定性进行了证明;分析了多模态中枢模式发生器模型参数对系统输出的影响;研究了蜿蜒运动中环境参数与蛇形机器人关节最优幅值的对应关系,从而确定了多模态中枢模式发生器幅值优化调整策略;并通过建立外部激励与模型参数之间的约束,使得蛇形机器人在多模态中枢模式发生器控制下具有三维运动能力以及相应的环境适应能力.最后,利用蛇形机器人平台验证了仿生控制方法的有效性以及与生物蛇步态的相似性.     

Dissection of the pheromone-modulated flight of moths using single-pulse response as a template

The upwind flight of male moths to conspecific females is mediated by the chemical and structural characteristics of a pheromone plume. We describe the reaction of maleCadra cautella, the almond moth, to the interception of single pulses of sex pheromone, the smallest structural units of odour plumes. Following loss of a pheromone plume, males cast, that is fly a crosswind course without progressing upwind. The response of casting males to interception of a pulse of 0.25 s duration was, after a delay of 0.21±0.07 s, to turn and briefly fly straighter upwind, resulting in average net upwind displacements of 18 cm in a 50 cm s^–1 wind. Upwind progress in the single-pulse response was the result of steering more upwind and an increase in airspeed, although average ground speed remained unchanged. During the last third of the surge, males turned crosswind, returning to casting flight. These behavioural reactions to pheromone contact and loss support the phasic-tonic model of odour-modulated flight, in which an underlying tonic counterturning rhythm, expressed upon pheromone loss, is briefly overridden by phasic upwind surges, expressed upon interception of the pheromone filament. The surge portion of the cast-surge-cast response was diminished and more crosswind if individual pulses were shorter (0.02 s), probably due to sub-optimal contact with pheromone. The cast-surge-cast response to interception of a single 0.25 s pulse was used as a template to interpret the form of flight tracks in plumes of known structure. The template matched portions of flight tracks of males flying in plumes of low pheromone pulse frequency, thus reflecting the male's pattern of pulse encounter. In plumes ensuring a high frequency of pulse interception, only the upwind surge portion of the template was expressed, resulting in nearly straight upwind flight tracks. Similar nearly straight upwind flight tracks occurred in flights along plumes of low pulse frequency with large volume. Thus flight tracks of maleC. cautella to point sources of pheromone depend on both the frequency and the size of filaments encountered.     

The distribution of carcinogens, 4-nitroquinoline-1-oxide and 4-hydroxyaminoquinoline-1-oxide, in the nervous system and its possible neurotoxicological significance.

4-NQO-14C can enter the grey matter parenchyma of the central nervous system of mice after i.v. injection. The level of its uptake by the central grey is higher than that taken up by the central white and by the trigeminal and spinal dorsal root ganglia. This pattern of distribution is strikingly different from that obtained after i.v. injection of 4-HAQO-14C, suggesting the possible occurrence of 4-NQO encephalomyelopathy having entirely different sites of lesions from those of 4-HAQO neuropathy.     

The distribution of carcinogens, 4-nitroquinoline-1-oxide and 4-hydroxyaminoquinoline-1-oxide,in the nervous system and its possible neurotoxicological significance

Summary 4-NQO-¹⁴C can enter the grey matter parenchyma of the central nervous system of mice after i.v. injection. The level of its uptake by the central grey is higher than that taken up by the central white and by the trigeminal and spinal dorsal root ganglia. This pattern of distribution is strikingly different from that obtained after i.v. injection of 4-HAQO-¹⁴C, suggesting the possible occurrence of 4-NQO encephalomyelopathy having entirely different sites of lesions from those of 4-HAQO neuropathy.This work was supported by a grant-in-Aid for Special Project Research from the Ministry of Education, Science and Culture of the Japanese Government (No. 321304, 1978).     

<Emphasis Type="Italic">Drosophila melanogaster</Emphasis> innate immunity: an emerging role for peptidoglycan recognition proteins in bacteria detection

Over the past years, parallel studies conducted in mammals and flies have emphasized the existence of common mechanisms regulating the vertebrate and invertebrate innate immune systems. This culminated in the discovery of the central role of the Toll pathway in Drosophila immunity and in the implication of Toll-like receptors (TLRs)/interleukin-1(IL-1) in the mammalian innate immune response. In spite of clear similarities, such as shared intracellular pathway components, important divergences are expected between the two groups, whose last common ancestor lived more than half a billion years ago. The most obvious discrepancies lie in the mode of activation of the signalling receptors by microorganisms. In mammals, TLRs are part of protein complexes which directly recognize microbe-associated patterns, whereas Drosophila Toll functions like a classical cytokine receptor rather than a pattern recognition receptor. Recent studies demonstrate that members of the evolutionarily conserved peptidoglycan recognition protein family play an essential role in microbial sensing during immune response of Drosophila.Received 26 June 2003; received after revision 29 July 2003; accepted 25 August 2003     

The mutual influence of aircraft aerodynamics and ship hydrodynamics in theory and experiment

As early as 1784, sharp-eyed engineers and scientists noted striking similarities between the dynamics of seagoing vessels and aerial vehicles. By the early twentieth century, naval engineers and scientists were developing and designing airplanes and dirigibles using empirical principles derived from naval architecture. Several key researchers in aerodynamics began their career as naval architects (David A. Taylor, William F. Durand and Jerome C. Hunsaker) and carried out their experiments in ship testing facilities. By the 1930s, however, the transfer of knowledge was irrevocably reversed as empiricism gave way to more fundamental, physics-based research. The rapid evolution of complex aircraft systems and flight envelopes led to new theoretical developments in aerodynamics and maneuvering, which quickly found their way into naval ship design. The theoretical and experimental results for airfoils, rigid airships and fixed-wing aircraft developed by Ludwig Prandtl, Theodore von Kármán, Max M. Munk and Hilda M. Lyon were employed in the hydrodynamic development of surface ships and submarines. This paper examines how the ideas, concepts and data from one discipline influenced the other and explores the processes by which that knowledge was transferred between disciplines.     

Myotoxic phospholipases A from snake venom,Pseudechis colletti,producing myoglobinuria in mice

Summary 2 proteins producing myoglobinuria in mice were isolated from the venom of the Australian elapid snakePseudechis colletti and identified as phospholipases A showing close similarities in amino acid composition to a similarly acting enzyme from a sea snake venom (Enhydrina schistosa).     

Mechanisms of flight steering in locusts

Summary Steering in flight by locusts provides a well-studied example of the modulation of a rhythmic motor output by unpredictable inputs from outside to produce adaptive behaviour, in this case a form of locomotion. The simplest form, correctional steering, allows the animal to compensate for unintentional deviations from course. Its mechanisms are relatively well understood. The central nervous circuitry which makes this behaviour possible can be thought of as an autopilot. The entire process, from sensory input to the aerodynamic effects of changed motor outputs, is here reviewed. Intentional change of course, either spontaneous or induced by a change in the outside world, is more complex: it demands not only active steering, but also the temporary disablement of the autopilot. The mechanisms by which this could be achieved are discussed.     

Flying insects: model systems in exercise physiology

Insect flight is the most energy-demanding exercise known. It requires very effective coupling of adenosine triphosphate (ATP) hydrolysis and regeneration in the working flight muscles.³¹P nuclear magnetic resonance (NMR) spectroscopy of locust flight muscle in vivo has shown that flight causes only a small decrease in the content of ATP, whereas the free concentrations of inorganic phosphate (P _i ), adenosine diphosphate (ADP) and adenosine monophosphate (AMP) were estimated to increase by about 3-, 5- and 27-fold, respectively. These metabolites are potent activators of glycogen phosphorylase and phosphofructokinase (PFK). Activation of glycolysis by AMP and P _i is reinforced synergistically by fructose 2,6-bisphosphate (F2,6P₂), a very potent activator of PFK. During prolonged flight locusts gradually change from using carbohydrate to lipids as their main fuel. This requires a decrease in glycolytic flux which is brought about, at least in part, by a marked decrease in the content of F2,6P₂ in flight muscle (by 80% within 15 min of flight). The synthesis of F2,6P₂ in flight muscle can be stimulated by the nervous system via the biogenic amine octopamine. Octopamine and F2,6P₂ seem to be part of a mechanism to control the rate of carbohydrate oxidation in flight muscle and thus function in the metabolic integration of insect flight.Dedicated to Dr. Ernst Zebe, Emeritus Professor of Zoology (University of Münster) on the occasion of his 70th birthday.     

Electrical activity of the pectoral muscles during gliding and flapping flight in the herring gull (Larus argentatus)

Summary Electromyographic recording from the pectoral muscles of the herring gull during flight showed that very little muscle activity is associated with gliding flight. However, the integrated gliding potentials could be increased very considerably by loading the bird. The muscle activity during gliding and flapping flight are in accordance with the known energy requirements for these 2 types of flight.This work was supported by NIH Research Grant HL-02228 and NIH Research Career Award 1-K6-GM-21, 522 to Prof. Schmidt-Nielsen. G. Goldspink was in receipt of a Science Research Council (UK) Research Grant.     

Ethnographic analogy,the comparative method,and archaeological special pleading

Ethnographic analogy, the use of comparative data from anthropology to inform reconstructions of past human societies, has a troubled history. Archaeologists often express concern about, or outright reject, the practice—and sometimes do so in problematically general terms. This is odd, as (or so I argue) the use of comparative data in archaeology is the same pattern of reasoning as the ‘comparative method’ in biology, which is a well-developed and robust set of inferences which play a central role in discovering the biological past. In pointing out this continuity, I argue that there is no ‘special pleading’ on the part of archaeologists in this regard: biologists must overcome analogous epistemic difficulties in their use of comparative data. I then go on to emphasize the local, empirically tractable ways in which particular ethnographic analogies may be licensed.     

我国东南沿海热带气旋登陆地点的空间模式分析

应用网络空间点模式分析方法中的最邻近分析方法以及集聚分析方法,对1949年至2006年我国东南沿海地区热带气旋登陆点进行了分析研究。结果表明：我国东南沿海地区热带气旋登陆点在空间上倾向于集聚分布。根据集聚分析的结果将我国东南沿海地区划分为五个区段,其中登陆频率最高的为广东省雷州半岛到阳江段。本研究中的分段方法与传统方法比较表明,传统的经验分类方法注重的是行政区界限,空间统计方法的分段统计意义明显,分段更加科学合理。     

A new functional interpretation of the visual system of male scale insects (Coccida,Homoptera)

Summary In a flight position with vertical body axis, both the dorsolateral and the characteristic ventral lens eyes of male coccid insects are arranged in a horizontal ring around the head. The interpretation that they mainly serve for stabilizing the flight position with regard to the horizon can explain the extraordinary structural features known for these eyes.     

神舟飞船交会对接自动控制系统设计

2011年11月、2012年6月、2013年6月相继发射的神舟八号、神舟九号、神舟十号无人和载人飞船分别与天宫一号目标飞行器成功地进行了4次自动交会对接.本文首先简要介绍了神舟飞船交会对接自动控制系统的组成和飞行阶段划分,重点对自动交会对接制导、导航和控制的设计方案和算法进行了介绍,对决定交会对接任务成败的导航精度、制导精度和控制精度进行了分析,并给出了在轨飞行验证结果.     

Endocrine basis of wing casting and flight muscle histolysis in the fire antSolenopsis invicta

Summary In the imported fire antSolenopsis invicta, wing casting and flight muscle histolysis are blocked by allatectomy. Treatment of alate allatectomized females with a synthetic mixture with high juvenile hormone activity induced wing casting and flight muscle histolysis. Apparently, wing casting and flight muscle histolysis in the fire ant are part of postemergence developmental program regulated, directly or indirectly, by the corpora allata.The author thanks the Entomology Department of the University of Georgia for postdoctoral support and Dr A.O. Lea for the use of his facilities.     

Hedgehog signaling in vertebrate and invertebrate limb patterning

Invertebrate and vertebrate limbs have very different anatomies and modes of development. Despite these differences, recent studies demonstrate that a significant overlap exists in the signals used to pattern invertebrate and vertebrate limbs. One of these signaling molecules is Hedgehog, a secreted protein that functions to coordinate growth and proliferation along the anterior-posterior axis of developing limbs. Recent studies indicate that the mechanism of action, regulation and function of Hedgehog signaling in Drosophila and vertebrate limb development are often quite similar, yet at other times are distinct. Here we highlight the similarities and differences between the use of Hedgehog signaling in these two systems.     

The peroxisomal protein import machinery – a case report of transient ubiquitination with a new flavor

The peroxisomal protein import machinery displays remarkable properties. Be it its capacity to accept already folded proteins as substrates, its complex architecture or its energetics, almost every aspect of this machinery seems unique. The list of unusual properties is still growing as shown by the recent finding that one of its central components, Pex5p, is transiently monoubiquitinated at a cysteine residue. However, the data gathered in recent years also suggest that the peroxisomal import machinery is not that exclusive and similarities with p97/Cdc48-mediated processes and with multisubunit RING-E3 ligases are starting to emerge. Here, we discuss these data trying to distill the principles by which this complex machinery operates. Received 16 July 2008; received after revision 25 August 2008; accepted 29 August 2008     

Ergastoplasmic granules,cytophysiological adaptation of the locusts corpora cardiaca to migratory flights?

Summary A good correlation was shown between the presence of ergastoplasmic granules in the glandular cells of the locusts corpora cardiaca and the flight activity of these insects.Research supported by grants A.T.P. No. 1831 and E.R.A. No. 620 from the Centre National de la Recherche Scientifique, French Ministry.