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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

Investigation of environmental and land use impacts in forested permafrost headwaters of the Selenga-Baikal river system,Mongolia-Effects on discharge,water quality and macroinvertebrate diversity

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International Soil and Water Conservation Research 2021年第4期9卷 605-619页

作者： Martin Pfeiffer Georg Küstner Erdenetsetseg Erdenesukh Wolf von tümpling Jürgen Hofmann Department of Biogeography University of BayreuthUniversitätsstraße 3095447 BayreuthGermany Department of Aquatic Ecosystem Analysis and Management(ASAM) Helmholtz Centre for Environmental Research-UFZBrückstraße 3a39114 MagdeburgGermany Department of Ecology National University of MongoliaBaga toiruu 47Ulaanbaatar 210646Mongolia Department of Animal Ecology and tropical Biology BiocenterJulius-Maximilians-Universität WürzburgAm Hubland97074 WürzburgGermany National Dong Hwa University No.1Sec.2Da Hsueh Rd.ShoufengHualien 97401Taiwan Central Laboratory for Water Analytics&Chemometrics Helmholtz Centre for Environmental Research-UFZBrückstrasse 3a39114 MagdeburgGermany Büro für Integrierten Gewässerschutz-BiG Werner-Voß-Damm 54 b12101 BerlinGermany

Headwater streams play a major role for provision of ecosystem services,*** *** investigated a high-altitude headwater catchment of the Kharaa River(including 411st-order rivers)to understand the impact of land cover(especially forest cover),environment and human usage on runoff,chemical water quality and macroinvertebrate fauna in a river basin under discontinuous permafrost conditions in an arid,sparsely populated region of *** verify our hypotheses that different landuses and environmental impacts in permafrost headwaters influence water quality,we investigated 105 sampling sites,37 of them at intermittent stream sections without water *** was positively impacted by land cover types steppe,grassland and forest and negatively by shrubland,forest burnt by wild fires(indicating a reduction of permafrost)and *** quality was affected by altitude,longitude and latitude,shrub growth and water *** diversity of macroinvertebrates was driven by water temperature,iron content of the water,flow velocity,and subbasin size(adjusted R^(2)=0.54).Sample plots clustered in three groups that differed in water chemistry,macroinvertebrate diversity,species composition and *** study confirms that steppes and grasslands have a higher contribution to runoff than forests,forest cover has a positive impact on water quality,and diversity of macroinvertebrates is higher in sites with less nutrients and *** excellent ecological status of the upper reaches of the Kharaa is severely threatened by forest fires and human-induced climate change and urgently needs to be conserved.

关键词： Ecosystem services Ephemeroptera-Plecoptera-trichoptera (EPt)complex GIS-based analysis IWRM-MoMo project Land use land cover(LULC) Natural reference state Runoff Self-purification capacity Stream water chemistry

VARIAtIONAL DISCREtIZAtION OF A CONtROL-CONStRAINED PARABOLIC BANG-BANG OPtIMAL CONtROL PROBLEM

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Journal of Computational Mathematics 2020年第1期38卷 14-40页

作者： Nikolaus von Daniels Michael Hinze Schwerpunkt Optimierung und Approximation Universitat HamburgBundesstrase 5520146 HamburgGermany

We consider a control-constrained parabolic optimal control problem without tikhonov term in the tracking *** the numerical treatment,we use variational discretization of its tikhonov regularization:For the state and the adjoint equation,we apply Petrov-Galerkin schemes in time and usual conforming finite elements in *** prove a-priori estimates for the error between the discretized regularized problem and the limit *** these estimates are not robust if the regularization parameter tends to zero,we establish robust estimates,which--depending on the problem's regularity——enhance the previous *** the special case of bang-bang solutions,these estimates are further improved.A numerical example confirms our analytical findings.

关键词： Optimal control Heat equation Control constraints Finite elements A-priori error estimates Bang-bang controls

Ectodysplasin A2 receptor-NF-κB-inducing kinase axis: a new player in muscle wasting to cancer cachexia

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Signal transduction and targeted therapy 2023年第11期8卷 5139-5140页

作者： Janusz von Renesse Peter Mirtschink Department of Visceral Thoracic and Vascular SurgeryUniversity Hospital and Faculty of Medicine DresdenTechnische Universität DresdenDresdenGermany National Center for tumor Diseases(NCt) Partner Site DresdenDresdenGerman Cancer Research Center(DKFZ)HeidelbergGermany Institute for Clinical Chemistry and Laboratory Medicine University Hospital and Faculty of MedicineTechnische Universität DresdenDresdenGermany

Cancer cachexia is a complex syndrome characterized by weight loss,muscle atrophy,and metabolic dysregulation,impeding cancer treatment and reducing patients’quality of *** can be seen as end-stage systemic manifestation common to various chronic *** triggers like aging,COPD,HIV,and cancer result in unresolved metabolic or inflammatory stress,leading to a maladaptive state.

关键词： cancer Cancer atrophy

A Dilemma of Language: “Natural Disasters” in Academic Literature

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International Journal of Disaster Risk Science 2019年第3期10卷 283-292页

作者： Ksenia Chmutina Jason von Meding School of Architecture Building and Civil EngineeringLoughborough UniversityLoughborough LE113TUUK Florida Institute for Built Environment Resilience Universityof FloridaGainesvilleFL32611USA

For decades sections of the academic community have been emphasizing that disasters are not ***, politicians, the media, various international organizations—and, more surprisingly, many established researchers working in disaster studies—are still widely using the expression 'natural disaster.' We systematically analyzed the usage of the expression 'natural disaster' by disaster studies researchers in 589 articles in six key academic journals representative of disaster studies research,and found that authors are using the expression in three principal ways:(1) delineating natural and human-induced hazards;(2) using the expression to leverage popularity;and(3) critiquing the expression 'natural disaster.' We also identified vulnerability themes that illustrate the context of 'natural disaster' usage. the implications of continuing to use this expression, while explicitly researching human vulnerability, are wide-ranging, and we explore what this means for us and our peers. this study particularly aims to stimulate debate within the disaster studies research community and related fields as to whether the term 'natural disaster' is really fit for purpose moving forward.

关键词： Academic communication Disasters Natural hazards Language

QoS Guided Min—Min Heuristic for Grid task Scheduling

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Journal of Computer Science & technology 2003年第4期18卷 442-451页

作者：何晓珊孙贤和 Gregor von Laszewski Department of Computer Science Illinois Institute of Technology IL USA Mathematics and Computer Science Division Argonne National Laboratory IL USA

task scheduling is an integrated component of computing. With the emergence of Grid and ubiquitous computing, new challenges appear in task scheduling based on properties such as security, quality of service, and lack of central control within distributed administrative domains. A Grid task scheduling framework must be able to deal with these issues. One of the goals of Grid task scheduling is to achieve high system throughput while matching applications with the available computing resources. this matching of resources in a non-deterministically shared heterogeneous environment leads to concerns over Quality of Service (QoS). In this paper a novel QoS guided task scheduling algorithm for Grid computing is introduced. the proposed novel algorithm is based on a general adaptive scheduling heuristics that includes QoS *** algorithm is evaluated within a simulated Grid environment. the experimental results show that the new QoS guided Min-Min heuristic can lead to significant performance gain for a variety of applications. the approach is compared with others based on the quality of the prediction formulated by inaccurate information.

关键词： QoS 任务调度网格计算服务质量非贡献计算

Nonclassical Radiation from two Atoms and Quantum Search Algorithms

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量子光学学报 2006年第B8期12卷 67-68页

作者： G. S. Agarwal Joachim von Zanthier t. Bastin Department of Physics Oklahoma State University Stillwater OK 74078-3072 USA Institute of Optics Information and Photonies University Erlangen-Nuremberg D - 91058 Erlangen Germany Institut de Physique Nueléaire Atomique et de Speetroseopie Universitéde Liege au Sart Tilman B - 4000 Liege Belgium

Food contamination as a pathway for lead exposure in children during the 2010–2013 lead poisoning epidemic in Zamfara,Nigeria

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Journal of Environmental Sciences 2018年第5期30卷 260-272页

作者： Simba tirima Casey Bartrem Ian von Lindern Margrit von Braun Douglas Lind Shehu Mohamed Anka Aishat Abdullahi terraGraphics International Foundation MoscowID 83843USA University of Idaho Environmental Science ProgramMoscowID 83843USA Zamfara Environmental Sanitation Agency Zamfara StateNigeria

In 2010, an estimated 400 to 500 children died of acute lead poisoning associated with artisanal gold mining in Zamfara, Nigeria. Processing of gold ores containing up to 10% lead within residential compounds put residents, especially children, at the highest risk. Principal routes of exposure were incidental ingestion and inhalation of contaminated soil and dusts. Several Nigerian and international health organizations collaborated to reduce lead exposures through environmental remediation and medical treatment. the contribution of contaminated food to total lead exposure was assessed during the environmental health response. Objectives of this investigation were to assess the influence of cultural/dietary habits on lead exposure pathways and estimate the contribution of contaminated food to children＇s blood lead levels（BLLs）. A survey of village dietary practices and staple food lead content was conducted to determine dietary composition, caloric intakes, and lead intake. Potential blood lead increments were estimated using bio-kinetic modeling techniques. Most dietary lead exposure was associated with contamination of staple cereal grains and legumes during post-harvest processing and preparation in contaminated homes. Average post-harvest and processed cereal grain lead levels were 0.32 mg/kg and 0.85 mg/kg dry weight, respectively. Age-specific food lead intake ranged from 7 to 78 μg/day. Lead ingestion and absorption were likely aggravated by the dusty environment, fasting between meals, and nutritional deficiencies. Contamination of staple cereal grains by highly bioavailable pulverized ores could account for as much as 11%–34% of children＇s BLLs during the epidemic, and were a continuing source after residential soil remediation until stored grain inventories were exhausted.

关键词： Artisanal mining Environmental health Lead poisoning Nigerian environmentalcontamination Dietary exposures Para-occupational exposuresChildren's health

Do viral infections protect from or enhance type 1 diabetes and how can we tell the difference?

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Cellular & Molecular Immunology 2011年第3期8卷 193-198页

作者： Urs Christen Matthias G von Herrath Pharmazentrum Frankfurt/ZAFES Klinikum der Goethe UniversitaätFrankfurt am MainGermany La Jolla Institute for Allergy and Immunology La JollaCAUSA

Virus infections have been implicated in both initiation of and protection from autoimmune diseases,such as type 1 diabetes(t1D).In this review we intend to reflect on recent evidence how viruses might on the one hand be involved in the pathogenesis of t1D and on the other hand induce a state of protection from autoimmune-mediated *** is important to acknowledge that human individuals encounter more than just one virus infection in their ***,it is important to integrate more than just one possible environmental triggering factor for autoimmune diseases to occur.

关键词： animal model enterovirus hygiene hypothesis molecular mimicry pathogens