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Johannes Lange of Heidelberg

Ralph H Major
1935 Annals of medical history  
Lange covers much ground in his one hundred and fifty epistles.  ...  Indeed Lange seems to either be entirely unaware or else deliberately ignored this new ferment in German medicine, but Lange was a traditionalist deeply rooted to the past.  ... 
pmid:33943631 pmcid:PMC7942308 fatcat:tki4iitozjcanfdwneusv2hzuu

Cognitive factors in distributed design

Sherman Y.T. Lang, John Dickinson, Ralph O. Buchal
2002 Computers in industry (Print)  
Ralph O. Buchal is an Associate Professor in the Department of mechanical and materials engineering at the University of Western Ontario.  ... 
doi:10.1016/s0166-3615(02)00012-x fatcat:dc6pnewdznf7pmpoz7o62cbeda

A caster-wheel-aware MPC-based motion planner for mobile robotics [article]

Jon Arrizabalaga, Niels van Duijkeren, Markus Ryll, Ralph Lange
2021 arXiv   pre-print
Differential drive mobile robots often use one or more caster wheels for balance. Caster wheels are appreciated for their ability to turn in any direction almost on the spot, allowing the robot to do the same and thereby greatly simplifying the motion planning and control. However, in aligning the caster wheels to the intended direction of motion they produce a so-called bore torque. As a result, additional motor torque is required to move the robot, which may in some cases exceed the motor
more » ... xceed the motor capacity or compromise the motion planner's accuracy. Instead of taking a decoupled approach, where the navigation and disturbance rejection algorithms are separated, we propose to embed the caster wheel awareness into the motion planner. To do so, we present a caster-wheel-aware term that is compatible with MPC-based control methods, leveraging the existence of caster wheels in the motion planning stage. As a proof of concept, this term is combined with a a model-predictive trajectory tracking controller. Since this method requires knowledge of the caster wheel angle and rolling speed, an observer that estimates these states is also presented. The efficacy of the approach is shown in experiments on an intralogistics robot and compared against a decoupled bore-torque reduction approach and a caster-wheel agnostic controller. Moreover, the experiments show that the presented caster wheel estimator performs sufficiently well and therefore avoids the need for additional sensors.
arXiv:2110.05604v1 fatcat:e2hjzvxnejfe3oycovi6pkavq4

Kinetics of proton exchange of phosphatidylethanolamine in phospholipid vesicles

E.K. Ralph, Y. Lange, A.G. Redfield
1985 Biophysical Journal  
Lange) and GM 20168 (to A. Redfield). This is contribution No. 1579 of the Department of Biochemistry, Brandeis University.  ...  H H H+ HNH * OH * NH 4 HN * HO -HNH. 7.0 (Vis) (Vi-) Scheme V RALPH ET AL.  ...  Vesicles were prepared by sonication, as previously described (Lange et al., 1975) .  ... 
doi:10.1016/s0006-3495(85)83868-6 pmid:4092067 pmcid:PMC1329438 fatcat:jwnlnzykzvfpjd5wfrjvm26fbq

A test of the free cash flow hypothesis

Larry H.P. Lang, RenéM. Stulz, Ralph A. Walkling
1991 Journal of Financial Economics  
Lang, Stulz, and Walkling (1989) and Servaes (1991) shows that bidder returns are larger for high q bidders and low q targets.  ...  We compute 4 using the Lindenberg and Ross (1981) algorithm, with some modifications described in Lang, Stulz, and Walkling (1989) .  ... 
doi:10.1016/0304-405x(91)90005-5 fatcat:yqhtfe5uzfcujh6bhuan2pqtle

Ludwig (Ralph) & Röseberg (Dorothee), Hrsg., Tout-Monde : Interkulturalität, Hybridisierung, Kreolisierung. Kommunikations- und gesellschaftstheoretische Modelle zwischen « alten » und « neuen » Räumen. Frankfurt a.M., Bern, Berlin, Bruxelles, Oxford, Wien : Peter Lang, coll. Sprache / Identität / Kultur, Band 8, 2010, 282 S. – ISBN 978-3-631-59168-0

Catherine Mazauric
2013 Etudes littéraires africaines  
Frankfurt a.M., Bern, Berlin, Bruxelles, Oxford, Wien : Peter Lang, coll. Sprache / Identität / Kultur, Band 8, 2010, 282 S.  ...  Études littéraires africaines Ludwig (Ralph) & Röseberg (Dorothee), Hrsg., Tout-Monde : Interkulturalität, Hybridisierung, Kreolisierung.  ...  Ludwig (Ralph) & Röseberg (Dorothee), Hrsg., Tout-Monde : Interkulturalität, Hybridisierung, Kreolisierung.  ... 
doi:10.7202/1021764ar fatcat:pmzdtzm575gzlonzvxmeh6spoy

A unified model of human semantic knowledge and its disorders

Lang Chen, Matthew A. Lambon Ralph, Timothy T. Rogers
2017 Nature Human Behaviour  
How is knowledge about the meanings of words and objects represented in the human brain? Current theories embrace two radically different proposals: either distinct cortical systems have evolved to represent different kinds of things, or knowledge for all kinds is encoded within a single domain-general network. Neither view explains the full scope of relevant evidence from neuroimaging and neuropsychology. Here we propose that graded category-specificity emerges in some components of the
more » ... nents of the semantic network through joint effects of learning and network connectivity. We test the proposal by measuring connectivity amongst cortical regions implicated in semantic representation, then simulating healthy and disordered semantic processing in a deep neural network whose architecture mirrors this structure. The resulting neuro-computational model explains the full complement of neuroimaging and patient evidence adduced in support of both domain-specific and domain-general approaches, reconciling long-standing disputes about the nature and origins of this uniquely human cognitive faculty.
doi:10.1038/s41562-016-0039 pmid:28480333 pmcid:PMC5417358 fatcat:c2qrmccbb5grfnx4njfgrcctiy

Enhanced Motion Control of a Self-Driving Vehicle Using Modelica, FMI and ROS

Nikolas Schröder, Oliver Lenord, Ralph Lange
2019 Proceedings Name  
This paper presents a new planar wheel model with bore friction, a control strategy to avoid locking conditions of floor vehicles with caster wheels, and the new FMI-Adapter software package, which connects the Functional Mock-up Interface (FMI) standard with the Robot Operating System (ROS). It is demonstrated how this technology enables a convenient model-based control design workflow. The approach is applied to the ActiveShuttle, a self-driving vehicle (SDV) for industrial logistics. After
more » ... logistics. After modeling the wheel friction characteristics of the Ac-tiveShuttle, a feed forward controller to avoid high friction torques at the caster wheels in critical operation scenarios is designed and validated by model-in-the-loop simulations. The control function is exported as Functional Mock-up Unit (FMU) for co-simulation. With help of the FMI-Adapter package, the FMU is integrated as ROS node into the service-oriented robot control architecture, enhancing the existing motion controller. The functionality and performance is tested and successfully verified on the ActiveShuttle Dev Kit prototype.
doi:10.3384/ecp19157441 dblp:conf/modelica/SchroderLL19 fatcat:4dsntfmx6jh2zenjtup2renc2a

Linking metabolic and contractile dysfunction in aged cardiac myocytes

Gregory P. Barton, Willem J. de Lange, John C. Ralphe, Judd Aiken, Gary Diffee
2017 Physiological Reports  
Aging is associated with declining cardiac contractile function as well as changes in metabolism and mitochondrial function. The relationship between age-related changes in cardiac metabolism and declining cardiac contractile function has not been determined. In order to define the role energetics play in changes in contractile function, we measured mitochondrial NADH, [NADH] m , during continuous contractions of isolated left ventricular myocytes from young (Y) and old (O) FBN rats. Second, we
more » ... BN rats. Second, we explored the role of metabolic disruption with rotenone and increased workload with isoproterenol (ISO) had on age-related changes in myocytes shortening. Single, intact myocytes were stimulated for 10 min of continuous contraction at either 2 Hz or 4 Hz while being perfused with Ringer's solution. Properties of shortening (peak shortening and rate of shortening) were measured at the onset (T0) and after 10 min (T10) of continuous contraction, and the decline in shortening over time (T10/T0) was determined. Although young and old myocytes had similar contractile function under resting conditions, old myocytes demonstrated decrements in [NADH] m during continuous stimulation, while young myocytes maintained constant [NADH]m over this time. In addition, old myocytes exhibited impaired contractile function to a workload (ISO) and metabolic (rotenone) stress compared to young myocytes. Taken together, these results demonstrated that old myocytes are susceptible to stress-induced contractile dysfunction which may be related to altered cellular energetics.
doi:10.14814/phy2.13485 pmid:29084842 pmcid:PMC5661240 fatcat:lw72w2k5qffi3jziqgr5yulqh4

A Constraint Programming Approach to Simultaneous Task Allocation and Motion Scheduling for Industrial Dual-Arm Manipulation Tasks [article]

Jan Kristof Behrens, Ralph Lange, Masoumeh Mansouri
2019 arXiv   pre-print
Modern lightweight dual-arm robots bring the physical capabilities to quickly take over tasks at typical industrial workplaces designed for workers. In times of mass-customization, low setup times including the instructing/specifying of new tasks are crucial to stay competitive. We propose a constraint programming approach to simultaneous task allocation and motion scheduling for such industrial manipulation and assembly tasks. The proposed approach covers dual-arm and even multi-arm robots as
more » ... ulti-arm robots as well as connected machines. The key concept are Ordered Visiting Constraints, a descriptive and extensible model to specify such tasks with their spatiotemporal requirements and task-specific combinatorial or ordering constraints. Our solver integrates such task models and robot motion models into constraint optimization problems and solves them efficiently using various heuristics to produce makespan-optimized robot programs. The proposed task model is robot independent and thus can easily be deployed to other robotic platforms. Flexibility and portability of our proposed model is validated through several experiments on different simulated robot platforms. We benchmarked our search strategy against a general-purpose heuristic. For large manipulation tasks with 200 objects, our solver implemented using Google's Operations Research tools and ROS requires less than a minute to compute usable plans.
arXiv:1901.07914v1 fatcat:l3u2qg2aznaozh5amtwh6yyvwq

A new species of Hirudo (Annelida: Hirudinidae): historical biogeography of Eurasian medicinal leeches

Naim Saglam, Ralph Saunders, Shirley A. Lang, Daniel H. Shain
2016 BMC Zoology  
Species of Hirudo are used extensively for medicinal purposes, but are currently listed as endangered due to population declines from economic utilization and environmental pollution. In total, five species of Hirudo are currently described throughout Eurasia, with Turkey being one of the major exporters of medicinal leech, primarily H. verbana. Results: To define the distribution of Hirudo spp. within Turkey, we collected 18 individuals from six populations throughout the country.
more » ... untry. Morphological characters were scored after dorsal and ventral dissections, and Maximum Likelihood (ML) and Bayesian Inference (BI) analyses resolved phylogenetic relationships using mitochondrial cytochrome c oxidase subunit I (COI), 12S ribosomal RNA (rRNA), and nuclear 18S rRNA gene fragments. Our results identify a new species of medicinal leech, Hirudo sulukii n. sp, in Kara Lake of Adiyaman, Sülüklü Lake of Gaziantep and Segirkan wetland of Batman in Turkey. Phylogenetic divergence (e.g., 10-14 % at COI), its relatively small size, unique dorsal and ventral pigmentation patterns, and internal anatomy (e.g., small and pointed atrium, medium-sized epididymis, relatively long tubular and arc formed vagina) distinguish H. sulukii n. sp. from previously described Hirudo sp. Conclusions: By ML and BI analyses, H. sulukii n. sp. forms a basal evolutionary branch of Eurasian medicinal leeches. Phylogeographic interpretations of the genus identify a European Hirudo "explosion" during the upper Miocene followed by geological events (e.g., Zanclean flood, mountain building) that likely contributed to range restrictions and regional speciation of extant members of the clade.
doi:10.1186/s40850-016-0002-x fatcat:xr2j4z7mrje3fp65tdlynrx3g4

Effects of riociguat in severe experimental pulmonary hypertension

Baktybek Kojonazarov, Michaela Lang, Norbert Weissmann, Friedrich Grimminger, Johannes-Peter Stasch, Werner Seeger, Hossein Ghofrani, Ralph Schermuly
2011 BMC Pharmacology  
doi:10.1186/1471-2210-11-s1-p39 pmcid:PMC3363233 fatcat:lck4ufuhqneztnfkul5gjdjlwu

Indexing source descriptions based on defined classes

Ralph Lange, Frank Dürr, Kurt Rothermel
2010 Proceedings of the Fourteenth International Database Engineering & Applications Symposium on - IDEAS '10  
Scaling heterogeneous information systems (HIS) to thousands of sources poses particular challenges to source discovery. It requires a powerful formalism for describing the contents of the sources in a concise manner and for formulating compatible queries as well as a suitable structure for indexing and retrieving the source descriptions efficiently. We propose an extended logic-based description formalism for large-scale HIS with structured sources and a shared ontology. The formalism refines
more » ... formalism refines existing approaches that describe the sources by constraints on the attribute value ranges in several ways: It allows for complex, nested descriptions based on defined classes. It supports alternative descriptions to express that a source may be discovered by different combinations of constraints. Finally, it allows to adjust between positive matching, similar to keyword-based discovery, and negative matching, as used in existing logicbased approaches. We further propose the SDC-Tree for indexing such source descriptions. To allow for efficient discovery, the SDC-Tree features multidimensional indexing capabilities for the different attributes and the IS-A hierarchy of the shared ontology, but also incorporates the existence or absence of constraints. For this purpose, it supports three different types of node split operations which exploit the expressiveness of the description formalism. Therefore, we also propose a generic split algorithm which can be used with arbitrary ontologies.
doi:10.1145/1866480.1866514 dblp:conf/ideas/LangeDR10 fatcat:62cqi7qp75hc5feq6x7spaahyy

Managerial performance, Tobin's Q, and the gains from successful tender offers

Larry H.P. Lang, RenéM. Stulz, Ralph A. Walkling
1989 Journal of Financial Economics  
Appendix: Estimation method for Tobin's q To compute Tobin's q, we follow the methods used by Lang and Litzenberger (1989) , who build on Lindenberg and Ross (1981) .  ...  Tobin's q As discussed in more detail in the appendix, we follow the method used in Lang and Litzenberger (1989) , who build on Lindenberg and Ross (1981) , to compute Tobin's q for the firms in our  ... 
doi:10.1016/0304-405x(89)90075-5 fatcat:4zcqb6m7x5gkjkizxy52wfczta

Specific visuomotor deficits due to alcohol intoxication: Evidence from the pro- and antisaccade paradigms

Christian Vorstius, Ralph Radach, Alan R. Lang, Christina J. Riccardi
2007 Psychopharmacology  
Rationale Alcohol affects a variety of human behaviors, including visual perception and motor control. Although recent research has begun to explore mechanisms that mediate these changes, their exact nature is still not well understood. Objectives The present study used two basic oculomotor tasks to examine the effect of alcohol on different levels of visual processing within the same individuals. A theoretical framework is offered to integrate findings across multiple levels of oculomotor
more » ... of oculomotor control. Materials and methods Twenty-four healthy participants were asked to perform eye movements in reflexive (pro-) and voluntary (anti-) saccade tasks. In one of two counterbalanced sessions, performance was measured after alcohol administration (mean BrAC = 69 mg%); the other served as a within-subjects no-alcohol comparison condition. Results Error rates were not influenced by alcohol intoxication in either task. However, there were significant effects of alcohol on saccade latency and peak velocity in both tasks. Critically, a specific alcohol-induced impairment (hypermetria) in saccade amplitudes was observed exclusively in the anti-saccade task. Conclusions The saccade latency data strongly suggest that alcohol intoxication impairs temporal aspects of saccade generation, irrespective of the level of processing triggering the saccade. The absence of effects on anti-saccade errors calls for further research into the notion of alcohol-induced impairment of the ability to inhibit prepotent responses. Furthermore, the specific impairment of saccade amplitude in the anti-saccade task under alcohol suggests that higher level processes involved in the spatial remapping of target location in the absence of a visually specified saccade goal are specifically affected by alcohol intoxication.
doi:10.1007/s00213-007-0954-1 pmid:17982744 fatcat:3ee6okkkw5gbpmyivf36ygxrnq
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