Enhancing Perceived Safety in Human–Robot Collaborative Construction Using Immersive Virtual Environments

Advances in robotics now permit humans to work collaboratively with robots. However, humans often feel unsafe working alongside robots. Our knowledge of how to help humans overcome this issue is limited by two challenges. One, it is difficult, expensive and time-consuming to prototype robots and set up various work situations needed to conduct studies in this area. Two, we lack strong theoretical models to predict and explain perceived safety and its influence on human–robot work collaboration (HRWC). To address these issues, we introduce the Robot Acceptance Safety Model (RASM) and employ immersive virtual environments (IVEs) to examine perceived safety of working on tasks alongside a robot. Results from a between-subjects experiment done in an IVE show that separation of work areas between robots and humans increases perceived safety by promoting team identification and trust in the robot. In addition, the more participants felt it was safe to work with the robot, the more willing they were to work alongside the robot in the future.University of Michigan Mcubed Grant: Virtual Prototyping of Human-Robot Collaboration in Unstructured Construction EnvironmentsPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145620/1/You et al. forthcoming in AutCon.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145620/4/You et al. 2018.pdfDescription of You et al. 2018.pdf : Published Versio

Sphingosine 1-phosphate and lysophosphatidic acid receptors: Agonist and antagonist binding and progress toward development of receptor-specific ligands

Sphingosine 1-phosphate and lysophosphatidic acid are two phospholipid growth factors whose importance in physiology and pathophysiology is becoming more and more apparent. Structure-activity relationships for agonism and antagonism at the thirteen known cell-surface and one intracellular receptor are described. Particular emphasis is placed on ligands having different selectivity than the parent molecules. Structural insights regarding agonist and antagonist recognition by the receptors from both computational modeling studies and crystallography are also discussed. © 2004 Elsevier Ltd. All rights reserved

Fatty alcohol phosphates are subtype-selective agonists and antagonists of lysophosphatidic acid receptors

A more complete understanding of the physiological and pathological role of lysophosphatidic acid (LPA) requires receptor subtype-specific agonists and antagonists. Here, we report the synthesis and pharmacological characterization of fatty alcohol phosphates (FAP) containing saturated hydrocarbon chains from 4 to 22 carbons in length. Selection of FAP as the lead structure was based on computational modeling as a minimal structure that satisfies the two-point pharmacophore developed earlier for the interaction of LPA with its receptors. Decyl and dodecyl FAPs (FAP-10 and FAP-12) were specific agonists of LPA2 (EC50 = 3.7 ± 0.2 μM and 700 ± 22 nM, respectively), yet selective antagonists of LPA3 (Ki = 90 nM for FAP-12) and FAP-12 was a weak antagonist of LPA1. Neither LPA1 nor LPA3 receptors were activated by FAPs; in contrast, LPA2 was activated by FAPs with carbon chains between 10 and 14. Computational modeling was used to evaluate the interaction between individual FAPs (8 to 18) with LPA2 by docking each compound in the LPA binding site. FAP-12 displayed the lowest docked energy, consistent with its lower observed EC50. The inhibitory effect of FAP showed a strong hydrocarbon chain length dependence with C12 being optimum in the Xenopus laevis oocytes and in LPA3-expressing RH7777 cells. FAP-12 did not activate or interfere with several other G-protein-coupled receptors, including S1P-induced responses through S1P1.2,3.5 receptors. These data suggest that FAPs are ligands of LPA receptors and that FAP-10 and FAP-12 are the first receptor subtype-specific agonists for LPA2

Synthesis and pharmacological evaluation of second-generation phosphatidic acid derivatives as lysophosphatidic acid receptor ligands

Short-chain phosphatidic acid derivatives, dioctanoyl glycerol pyrophosphate (DGPP 8:0, 1) and phosphatidic acid 8:0 (PA 8:0, 2), were previously identified as subtype-selective LPA1 and LPA3 receptor antagonists. Recently, we reported that the replacement of the phosphate headgroup by thiophosphate in a series of fatty alcohol phosphates (FAP) improves agonist as well as antagonist activities at LPA GPCR. Here, we report the synthesis of stereoisomers of PA 8:0 analogs and their biological evaluation at LPA GPCR, PPARγ, and ATX. The results indicate that LPA receptors stereoselectively interact with glycerol backbone modified ligands. We observed entirely stereospecific responses by dioctyl PA 8:0 compounds, in which (R)-isomers were found to be agonists and (S)-isomers were antagonists of LPA GPCR. From this series, we identified compound 13b as the most potent LPA3 receptor subtype-selective agonist (EC50 = 3 nM), and 8b as a potent and selective LPA3 receptor antagonist (Ki = 5 nM) and inhibitor of ATX (IC50 = 600 nM). Serinediamide phosphate 19b was identified as an LPA3 receptor specific antagonist with no effect on LPA1, LPA2, and PPARγ. © 2005 Elsevier Ltd. All rights reserved

Molecular basis for lysophosphatidic acid receptor antagonist selectivity

Recent characterization of lysophosphatidic acid (LPA) receptors has made possible studies elucidating the structure-activity relationships (SAR) for agonist activity at individual receptors. Additionally, the availability of these receptors has allowed the identification of antagonists of LPA-induced effects. Two receptor-subtype selective LPA receptor antagonists, one selective for the LPA1/EDG2 receptor (a benzyl-4-oxybenzyl N-acyl ethanolamide phosphate, NAEPA, derivative) and the other selective for the LPA3/EDG7 receptor (diacylglycerol pyrophosphate, DGPP, 8:0), have recently been reported. The receptor SAR for both agonists and antagonists are reviewed, and the molecular basis for the difference between agonism and antagonism as well as for receptor-subtype antagonist selectivity identified by molecular modeling is described. The implications of the newly available receptor-subtype selective antagonists are also discussed. © 2002 Elsevier Science B.V. All rights reserved

Book of Abstracts of the 2nd International Conference on Applied Mathematics and Computational Sciences (ICAMCS-2022)

It is a great privilege for us to present the abstract book of ICAMCS-2022 to the authors and the delegates of the event. We hope that you will find it useful, valuable, aspiring, and inspiring. This book is a record of abstracts of the keynote talks, invited talks, and papers presented by the participants, which indicates the progress and state of development in research at the time of writing the research article. It is an invaluable asset to all researchers. The book provides a permanent record of this asset. Conference Title: 2nd International Conference on Applied Mathematics and Computational SciencesConference Acronym: ICAMCS-2022Conference Date: 12-14 October 2022Conference Organizers: DIT University, Dehradun, IndiaConference Mode: Online (Virtual