1,872 research outputs found
Bilateral Control Architectures for Telerobotics
No full textThis chapter introduces and surveys bilateral (master-slave) control methods and system architectures for telerobotics known in the literature. The discussion takes a focus most relevant to subsequent chapters, see [1–3] for complementary and more complete surveys.
Firstly, an introductory example of a control-oriented block diagram formulation for a typical two-channel force-velocity architecture is presented, where the human system interface (master) is force controlled and the teleoperator (slave) is velocity controlled. Then a
network theoretic view using n-ports is taken and the basic concept of passivity is explained meaning that an interconnection of passive subsystems results in an overall passive system. Transparency is defined, meaning that the human operator should ideally feel as if directly acting in the remote environment (is not able to feel the technical systems/communication network at all). The well known and for ideal transparency required four-channel architecture
is presented. The important discussion of time delay in the communication network, which impairs or might threaten stability properties of the closed loop teleoperation system, is then discussed. The most successful approach using the scattering (wave variable) transformation approach is presented, which guarantees that the communication two-port is lossless (passive) for arbitrary constant time delay. Finally, we mention the key challenges in the design of bilateral teleoperation systems and give a short preview of the subsequent chapters addressing some of these challenges
Polyurenthane surface modification. Hydrogels
No full textSaez Ferre, S. (2011). Polyurenthane surface modification. Hydrogels. https://riunet.upv.es/handle/10251/12125.Archivo delegad
Images of Environmental Damage in the Works of Rosario Ferre
No full textColor poster with text and images.This study examines the texts of Puerto Rican author Rosario Ferre, focusing on her use of imagery and duality to bring awareness to the environmental damge done to the island of Puerto Rico during the industrialization movement. The research focuses on thre of Ferre's works; Papeles de Pandora (The Youngest Doll), Maldito Amor (Sweet Diamond Dust), and La Casa de la Laguna (The House on the Lagoon) with the purpose verifying if the the fiction Ferre writes is historically accurate or if the environmental damage she exposes is unfounded.University of Wisconsin--Eau Claire Office of Research and Sponsored Programs; University of Wisconsin--Eau Claire Dept. of Education Postbaccalaureate Achievement Progra
How receptor mosaics decode transmitter signals. Possible relevance of cooperativity
No full textIt has been demonstrated that receptor–receptor interactions between G-protein-coupled receptors (GPCRs) occur at the plasma-membrane level. It has also been shown that clustering of GPCRs in aggregates or receptor mosaics (RMs) results in the reciprocal modulation of their binding and decoding characteristics. It is hypothesized that cooperativity plays an important part in the decoding of signals processed by RMs of GPCRs. Thus, the binding of the ligand at one receptor alters the likelihood of the same ligand binding at the next site, in the case of RMs, formed by identical receptors and/or by iso-receptors (receptors that bind the same ligand)
A Proof of Grilliot's Theorem
No full textWe would like to thank Juliette Kennedy, Phokion Kolaitis, and Andreas Weiermann for their comments. The first author was partially supported by FWF grant I4513N and FWO grant 3E017319. The second author was partially supported by FWO grant 11O0923N
Multiple intramembrane receptor-receptor interactions in the regulation of striatal dopamine D2 receptors
No full textAdenosine A(2A), group I mGlu and neurotensin receptors have been previously found to modulate the binding characteristics of dopamine D2 receptors in membrane preparations from rat striatum. In the present study it is shown that stimulation of different combinations of striatal A(2A), group I mGlu and neurotensin receptors induce different effects on the modulation of D2 receptor binding to those obtained when they are separately stimulated using maximal effective concentrations. In competitive inhibition experiments of dopamine versus the D2 receptor antagonist [3H]raclopride the addition of the A(2A) receptor agonist CGS 21680, the group I mGlu receptor agonist DHPG or neurotensin induced a decrease in the affinity of the high affinity state of the dopamine D2 receptors for dopamine. When added together CGS 21680 plus neurotensin induced the same effect as when administered alone, CGS 21680 plus DHPG induced a synergistic effect and DHPG plus neurotensin lost their modulating effect on D2 receptor binding. These results demonstrate the existence of multiple intramembrane receptor-receptor interactions in the regulation of striatal D2 receptors
Adenosine A2A agonists: A potential new type of atypical antipsychotic
No full textThe systemic intraperitoneal (i.p.) administration of the adenosine A2A agonist CGS 21680 was found to dose-dependently antagonize spontaneous and amphetamine-induced (1 mg/kg i.p.) motor activity with similar ED50 values (about 0.2 mg/kg). The ratios between the ED50 values for induction of catalepsy and for antagonizing amphetamine-induced motor activity for CGS 21680, haloperidol, and clozapine were 12,2, and > 30, respectively. Furthermore, CGS 23680 was comparably much stronger than haloperidol or clozapine at antagonizing the motor activity induced by phencyclidine (2 mg/kg subcutaneonsly) than motor activity induced by amphetamine (1 mg/kg i.p.). In conclusion, the present results show a clear "atypical" antipsychotic profile of the adenosine A2A agonist CGS 21680 in animal models. © 1997 American College of Neuropsychopharmacohgy. Published by Elsevier Science Inc
Women's choices of hospital for breast cancer surgery in Italy: Quality and equity implications
No full text: This paper employs mixed logit regression to investigate the effects of providers characteristics on women's choice of hospital for breast surgery. Patient level data are used to model choices in Tuscany region, Italy. In particular, we focus on the effects of travel time and hospital quality indicators including quality standard (volumes of breast surgery), measurement of process (waiting times) and quality of surgical procedures. Variation in preferences related to individual characteristics such as age, education and travel distance from the hospital are also considered. Findings show that, on average, women prefer closer hospital with longer waiting times and higher quality (high volumes of interventions). We found preference heterogeneity associated to education: travel distance affects choice especially among less educated women (regardless of age), while among younger women (<65 years), less educated ones prefer shorter waiting times. These results could be used to optimize the allocation of resources toward breast cancer units that meet quality and efficacy standards to increase the efficiency and responsiveness of breast cancer care
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