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Biomimetic Sensors:Active Electrolocation of Weakly Electric Fish as a Model for Active Sensing in Technical Systems

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Journal of Bionic Engineering 2007年第2期4卷 85-90页

作者： Gerhard von der Emde Zoological Institute University of Bonn53115 BonnGermany

Instead of vision, many nocturnal animals use alternative senses for navigation and object detection in their dark environment. For this purpose, weakly electric mormyrid fish employ active electrolocation, during which they discharge a specialized electric organ in their tail which discharges electrical pulses. Each discharge builds up an electrical field around the fish, which is sensed by cutaneous electroreceptor organs that are distributed over most of the body surface of the fish. Nearby objects distort this electrical field and cause a local alteration in current flow in those electroreceptors that are closest to the object. By constandy monitoring responses of its electroreceptor organs, a fish can detect, localize, and identify environmental objects. Inspired by the remarkable capabilities of weakly electric fish in detecting and recognizing objects, we designed technical sensor systems that can solve similar problems of remote object sensing. We applied the principles of active electrolocation to technical systems by building devices that produce electrical current pulses in a conducting medium （water or ionized gases） and simultaneously sense local current density. depending on the specific task a sensor was designed for devices could （i） detect an object, （ii） localize it in space, （iii） determine its distance, and （iv） measure properties such as material properties, thickness, or material faults. Our systems proved to be relatively insensitive to environmental disturbances such as heat, pressure, or turbidity. They have a wide range of applications including material identification, quality control, non-contact distance measurements, medical applications and many more. despite their astonishing capacities, our sensors still lag far behind what electric fish are able to achieve during active electrolocation. The understanding of the neural principles governing electric fish sensory physiology and the corresponding optimization of our sensors to solve

关键词： biomimetic weakly electric fish sensory system electrolocation sensor

Recent results for single meson production from the Crystal-Barrel/TAPS experiment at ELSA

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Chinese Physics C 2009年第12期33卷 1056-1062页

作者： R. Beck HISKP University of bonn 53115 Bonn Germany

The present focus of the CBELSA/TAPS experiment is on meson-photoproduction off the nucleon using polarized photons and polarized targets. Here first preliminary results on the reactions γp → pπ and γp → pπ for both circularly and linearly polarized photons and a longitudinally polarized target are presented. Preliminary results for the beam asymmetry ∑ and the double polarization observable G have been extracted for both reactions using the linear polarization data. From the circular polarization data the observable E has been determined. due to the near 4π angular coverage of the detector system these results cover almost the full solid angle.

关键词： meson photoproduction double polarization baryon spectroscopy

Photoproduction of ω-Mesons at ELSA and the role of azimuthal asymmetries

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Chinese Physics C 2009年第12期33卷 1146-1152页

作者： H. Schmieden Rheinische Friedrich-Wilhelms-Universitt Physikalisches Institut D-53115 Bonn Germany

Measurements of ω photoproduction of the Crystal-Barrel/TAPS experiment at the ELSA accelerator of bonn University are presented which used linearly polarized tagged photon beam from threshold to Eγ = 1700MeV. The azimuthal asymmetries ∑and ∑πindicate s-channel resonance contributions on top of the established t-channel exchange processes. These findings are further enhanced by a very first measurement of the G-asymmetry which, in addition to the polarized photon beam, also requires a longitudinally polarized proton target. An intuitive interpretation of the specific sensitivity of the azimuthal asymmetries to the reaction mechanisms involved is given.

关键词： baryon resonances photoproduction vector mesons polarization

Alpine Activity Patterns of Mitopus morio(Fabricius, 1779) are Induced by Variations in Temperature and Humidity at different Scales in Central Norway

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Journal of Mountain Science 2014年第3期11卷 644-655页

作者： Nils HEIN Roland PAPE Oliver-d. FINCH Jorg LOFFLER department of C-eography University of Bonn Meckenheimer AUee 166 D-53115 Bonn Germany Achtern Nordpol 8 D-26180 Rastede Germany

Our research addresses questions about how micro-climate affects activity abundance of a common and widespread harvestman in an alpine ecosystem. Activity patterns of the Harvestman Mitopus morio(Fabricius, 1779) were studied along different alpine gradients in the central Norwegian Scandes. Within a nested design, we surveyed 18 alpine habitats with pitfall traps and microclimatological equipment along oceanic-continental, two elevational, and(fine-scaled) microtopographic gradients. Sites in the oceanic region of the Scandes showed generally higher abundance of M. morio than sites in the continental region. Furthermore, along the elevational gradient, middle-alpine sites showed higher abundances than low-alpine sites. These general patterns are best explained by higher humidity in the oceanic region and in the middlealpine belt. Focusing at a finer scale, i.e. one elevational level within each region, revealed partly opposing activity patterns within relatively short distances. While in the western middle-alpine belt these patterns were best explained by humidityrelated measures but now with higher activity abundance during drier conditions, in the drier eastern middle-alpine belt heat sums rather than humidity were found to be the best explanatoryvariables for the observed patterns. Hence, our results imply a pronounced different reaction of the two populations towards climatic variables that partly even contradict the previously described general pattern. Regardless whether these differences in activity abundance in M. morio are a form of phenotypic plasticity or adaptation, our findings stress the importance of detailed autecological knowledge combined with fine-scaled climatic measurements when aiming at predictions about possible future ecosystem structures and spatiotemporal phenomena. M. morio proves to be an ideal biogeographic model organism for understanding spatio-temporal responses of alpine ecosystems under modified climatic conditions.

关键词： Climate gradients Opiliones Arctic-alpine ecosystems High mountains Scandinavia

Teleportation with an Arbitrary Mixed Resource as a Trace-Preserving Quantum Channel

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Communications in Theoretical Physics 2002年第3期38卷 301-304页

作者： Sergio Albeverio FEI Shao-Ming YANG Wen-Li Institut fiir Angewandte Mathematik Universitat Bonn D-53115 Germany Institut fiir Angewandte Mathematik Universitat Bonn D-53115 Germany department of Mathematics Capital Normal University Beijing 100037 China Physikalisches Institut der Universitat Bonn 53115 Bonn Germany Institute of Modern Physics Northwest University Xi'an 710069 China

General conditions are given in order to perform a perfect teleportation process in the case where theHilbert spaces involved have different dimensions. An explicit expression is obtained for the quantum channel associatedwith the standard teleportation protocol To with an arbitrary mixed state resource. The transmission fidelity of thecorresponding quantum channel is given.

关键词： teleportation, fidelity

Photoproduction of multi-meson final states–recent results from the Crystal-Barrel/TAPS experiment at ELSA-

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Chinese Physics C 2009年第12期33卷 1105-1112页

作者： U. Thoma HISKP Universitt Bonn Nussallee 14-16 53115 Bonn Germany

Multi-meson final states such as γp →pπ0π0 and γp →pπ0η have been investigated with the Crystal-Barrel/TAPS experiment at ELSA. Baryon cascades via △π and △η and also via higher mass baryon resonances are clearly observed. Based on this data and on data from other reactions a partial wave analysis has been performed from which partial decay widths of various N＊ and △＊ states into the different pπ0π0 and pπ0η decay channels have been determined, leading partly to unexpected results. In addition, polarisation observables have been investigated. The beam asymmetry X has been determined for both reactions and double polarisation data using a longitudinally polarised target and a circularly or linearly polarised photon beam has been taken. Given the angular coverage of the Crystal-Baxrel/TAPS experiment this data covers almost the full angular range and phase space. This data will provide new and important information for the partial wave analyses and bring us one step closer towards a complete experiment.

关键词： baryon spectroscopy photoproduction multi-meson final states polarisation observables

Function Modeling of the Infrared Organ of ＂Little Ash Beetle＂ Acanthocnemus Nigricans （Coleoptera, Acanthocnemidae）

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Journal of Bionic Engineering 2016年第4期13卷 650-658页

作者： Zupeng Zhou Yubing Gong daoguo Yang Anke Schmitz Helmut Schmitz School of Mechanical and Electrical Engineering Guilin University of Electronic Technology Guilin 541004 China Institute of Zoology University of Bonn Poppelsdorfer Schloss D-53115 Bonn Germany

Acanthocnemus nigricans is an inconspicuous pyrophilous beetle that approaches forest fires. The beetle is equipped with a pair of unique infrared （IR） receptors on its prothorax that allows it to detect hot surfaces in flight. The IR receptor consists of a little disc bearing about 90 tiny sensilla on its anterior half. The disc sensilla are unique in insects and their functions are largely unknown. Using a 3d reconstruction of the head and thorax we performed case studies to reveal different position-dependent expositions of the IR receptors to incoming radiation~ Results show that the spatiotemporal pattern in which different sectors of the disc are exposed provides the beetle with unambiguous information about its current direction to an IR source. As a striking structural element, the disc sensilla contain an electron-dense rod connecting an outer peg to the inner sensory cell. Finite element simulations suggest that the rod serves as a heat conductor directing heat to the thermosensitive cell inside the disc. Thus the disc sensilla can be interpreted as discrete temperature reading points. The resulting pattern of stimulated/deactivated sensilla, therefore, could provide the flying beetle with spatiotemporal information about its current position relative to an IR source. Possible biomimetic perspectives of the findings are discussed.

关键词： infrared receptor pyrophilous insects fire detection insect sensillum

The Subcellular Localization and Blue-Light- Induced Movement of Phototropin 1-GFP in Etiolated Seedlings of Arabidopsis thalianaw

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Molecular Plant 2008年第1期1卷 103-117页

作者： Ying-Lang Wan William Eisinger david Ehrhardt Ulrich Kubitscheck Frantisek Baluska Winslow Briggs dept Plant Cell Biology Institute of Cellular and Molecular Botany University of Bonn Kirschallee 1 D-53115 Bonn Germany dept Biology Santa Clara University Santa Clara CA 95053 dept Plant Biology Carnegie Institution of Washington Stanford CA 94305 Institute for Physical and Theoretical Chemistry Wegelerstr. 12 D-53115 Bonn Germany

Phototropin 1 （photl） is a photoreceptor for phototropism, chloroplast movement, stomatal opening, leaf expansion, and solar tracking in response to blue light. Following earlier work with PHOTI：：GFP （Sakamoto and Briggs, 2002）, we investigated the pattern of cellular and subcellular localization of photl in 3-4 d old etiolated seedlings of Arabidopsis thalinana. As expressed from native upstream sequences, the PHOTT：GFP fusion protein is expressed strongly in the abaxial tissues of the cotyledons and in the elongating regions of the hypocotyl. It is moderately expressed in the shoot/root transition zone and in cells near the root apex. A fluorescence signal is undetectable in the root epidermis, root cap, and root apical meristem itself. The plasma membranes of mesophyll cells near the cotyledon margin appear labeled uniformly but cross-walls created by recent cell divisions are more strongly labeled. The pattern of labeling of individual cell types varies with cell type and developmental stage. Blue-light treatment causes PHOTI：：GFP, initially relatively evenly distributed at the plasma membrane, to become reorganized into a distinct mosaic with strongly labeled punctate areas and other areas completely devoid of fluorescenco a phenomenon best observed in cortical cells in the hypocotyl elongation region. Concomitant with or following this reorganization, PHOTT：GFP moves into the cytoplasm in all cell types investigated except for guard cells. It disappears from the cytoplasm by an unidentified mechanism after several hours in darkness. Neither its appearance in the cytoplasm nor its eventual disappearance in darkness is prevented by the translation inhibitor cycloheximide, although the latter process is retarded. We hypothesize that blue-light-induced photl relocalization modulates blue-light-activated signal transduction.

关键词： Phototropin 1 (phot1) PHOT1::GFP Arabidopsis thalianaw

Matrix Tensor Product Approach to the Equivalence of Multipartite States under Local Unitary Transformations

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Communications in Theoretical Physics 2006年第2期45卷 267-270页

作者： GAO Xiu-Hong S. Alberverio FEI Shao-Ming WANG Zhi-Xi department of Mathematics Capital Normal University Beijing 100037 China Institut fur Angewandte Mathematik Universitat Bonn D-53115 Bonn Germany

The equivalence of multipartite quantum mixed states under local unitary transformations is studied. A criterion for the equivalence of non-degenerate mixed multipartite quantum states under local unitary transformati... 详细信息

关键词： local unitary transformation multipartite quantum mixed state tensor decomposable