Conformation of bis-nitroxide polarizing agents by multi-frequency EPR spectroscopy

In the human-centered research on automated driving, it is common practice to describe the vehicle behavior by means of terms and definitions related to non-automated driving. However, some of these definitions are not suitable for this purpose. This paper presents an ontology for automated vehicle behavior which takes into account a large number of existing definitions and previous studies. This ontology is characterized by an applicability for various levels of automated driving and a clear conceptual distinction between characteristics of vehicle occupants, the automation system, and the conventional characteristics of a vehicle. In this context, the terms ‘driveability’, ‘driving behavior’, ‘driving experience’, and especially ‘driving style’, which are commonly associated with non-automated driving, play an important role. In order to clarify the relationships between these terms, the ontology is integrated into a driver-vehicle system. Finally, the ontology developed here is used to derive recommendations for the future design of automated driving styles and in general for further human-centered research on automated driving.

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Insights into the Antioxidant Mechanism of Newly Synthesized Benzoxazinic Nitrones: In Vitro and In Silico Studies with DPPH Model Radical

Antioxidants ◽

10.3390/antiox10081224 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1224

Author(s):

Stefania Marano ◽

Cristina Minnelli ◽

Lorenzo Ripani ◽

Massimo Marcaccio ◽

Emiliano Laudadio ◽

...

Keyword(s):

Antioxidant Activity ◽

Epr Spectroscopy ◽

Point Of View ◽

Uv Spectrophotometry ◽

Design And Synthesis ◽

Antioxidant Mechanism ◽

Primary Mechanism ◽

In Silico Studies ◽

Wide Range

Synthetic nitrone spin-traps are being explored as therapeutic agents for the treatment of a wide range of oxidative stress-related pathologies, including but not limited to stroke, cancer, cardiovascular, and neurodegenerative diseases. In this context, increasing efforts are currently being made to the design and synthesis of new nitrone-based compounds with enhanced efficacy. The most researched nitrones are surely the ones related to α-phenyl-tert-butylnitrone (PBN) and 5,5-dimethyl-1-pyrroline N-oxide (DMPO) derivatives, which have shown to possess potent biological activity in many experimental animal models. However, more recently, nitrones with a benzoxazinic structure (3-aryl-2H-benzo[1,4]oxazin-N-oxides) have been demonstrated to have superior antioxidant activity compared to PBN. In this study, two new benzoxazinic nitrones bearing an electron-withdrawing methoxycarbonyl group on the benzo moiety (in para and meta positions respect to the nitronyl function) were synthesized. Their in vitro antioxidant activity was evaluated by two cellular-based assays (inhibition of AAPH-induced human erythrocyte hemolysis and cell death in human retinal pigmented epithelium (ARPE-19) cells) and a chemical approach by means of the α,α-diphenyl-β-picrylhydrazyl (DPPH) scavenging assay, using both electron paramagnetic resonance (EPR) spectroscopy and UV spectrophotometry. A computational approach was also used to investigate their potential primary mechanism of antioxidant action, as well as to rationalize the effect of functionalization on the nitrones reactivity toward DPPH, chosen as model radical in this study. Further insights were also gathered by exploring the nitrone electrochemical properties via cyclic voltammetry and by studying their kinetic behavior by means of EPR spectroscopy. Results showed that the introduction of an electron-withdrawing group in the phenyl moiety in the para position significantly increased the antioxidant capacity of benzoxazinic nitrones both in cell and cell-free systems. From the mechanistic point of view, the calculated results closely matched the experimental findings, strongly suggesting that the H-atom transfer (HAT) is likely to be the primary mechanism in the DPPH quenching.

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A Roadmap for the Future Design of Human-Robot Collaboration

IFAC-PapersOnLine ◽

10.1016/j.ifacol.2020.12.2748 ◽

2020 ◽

Vol 53 (2) ◽

pp. 10196-10201

Author(s):

Hans-Jürgen Buxbaum ◽

Sumona Sen ◽

Ruth Häusler

Keyword(s):

Future Design ◽

The Future ◽

Human Robot Collaboration

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Tripeptide Self-Assembly into Bioactive Hydrogels: Effects of Terminus Modification on Biocatalysis

Molecules ◽

10.3390/molecules26010173 ◽

2020 ◽

Vol 26 (1) ◽

pp. 173

Author(s):

Marina Kurbasic ◽

Ana M. Garcia ◽

Simone Viada ◽

Silvia Marchesan

Keyword(s):

Self Assembly ◽

The Self ◽

Chemical Modifications ◽

Ability To Work ◽

Active Compounds ◽

Future Design ◽

Self Organized ◽

The Future ◽

Bio Material ◽

Supramolecular Catalysts

Bioactive hydrogels based on the self-assembly of tripeptides have attracted great interest in recent years. In particular, the search is active for sequences that are able to mimic enzymes when they are self-organized in a nanostructured hydrogel, so as to provide a smart catalytic (bio)material whose activity can be switched on/off with assembly/disassembly. Within the diverse enzymes that have been targeted for mimicry, hydrolases find wide application in biomaterials, ranging from their use to convert prodrugs into active compounds to their ability to work in reverse and catalyze a plethora of reactions. We recently reported the minimalistic l-His–d-Phe–d-Phe for its ability to self-organize into thermoreversible and biocatalytic hydrogels for esterase mimicry. In this work, we analyze the effects of terminus modifications that mimic the inclusion of the tripeptide in a longer sequence. Therefore, three analogues, i.e., N-acetylated, C-amidated, or both, were synthesized, purified, characterized by several techniques, and probed for self-assembly, hydrogelation, and esterase-like biocatalysis. This work provides useful insights into how chemical modifications at the termini affect self-assembly into biocatalytic hydrogels, and these data may become useful for the future design of supramolecular catalysts for enhanced performance.

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Investigating the dynamic nature of the ABC transporters: ABCB1 and MsbA as examples for the potential synergies of MD theory and EPR applications

Biochemical Society Transactions ◽

10.1042/bst20150138 ◽

2015 ◽

Vol 43 (5) ◽

pp. 1023-1032 ◽

Cited By ~ 10

Author(s):

Thomas Stockner ◽

Anna Mullen ◽

Fraser MacMillan

Keyword(s):

Crystal Structures ◽

Conformational Changes ◽

Abc Transporters ◽

Epr Spectroscopy ◽

Structural Information ◽

Dynamic Properties ◽

Molecular System ◽

Synergistic Effects ◽

Md Simulations ◽

Substrate Spectrum

ABC transporters are primary active transporters found in all kingdoms of life. Human multidrug resistance transporter ABCB1, or P-glycoprotein, has an extremely broad substrate spectrum and confers resistance against chemotherapy drug treatment in cancer cells. The bacterial ABC transporter MsbA is a lipid A flippase and a homolog to the human ABCB1 transporter, with which it partially shares its substrate spectrum. Crystal structures of MsbA and ABCB1 have been solved in multiple conformations, providing a glimpse into the possible conformational changes the transporter could be going through during the transport cycle. Crystal structures are inherently static, while a dynamic picture of the transporter in motion is needed for a complete understanding of transporter function. Molecular dynamics (MD) simulations and electron paramagnetic resonance (EPR) spectroscopy can provide structural information on ABC transporters, but the strength of these two methods lies in the potential to characterise the dynamic regime of these transporters. Information from the two methods is quite complementary. MD simulations provide an all atom dynamic picture of the time evolution of the molecular system, though with a narrow time window. EPR spectroscopy can probe structural, environmental and dynamic properties of the transporter in several time regimes, but only through the attachment sites of an exogenous spin label. In this review the synergistic effects that can be achieved by combining the two methods are highlighted, and a brief methodological background is also presented.

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Damage Assessment of Historic Earthen Sites after the 2007 Earthquake in Peru

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.133-134.665 ◽

2010 ◽

Vol 133-134 ◽

pp. 665-670 ◽

Cited By ~ 1

Author(s):

N. Claudia ◽

B. Cancino

Keyword(s):

Multidisciplinary Team ◽

Damage Assessment ◽

Rapid Assessment ◽

Future Design ◽

The Future ◽

Earthen Buildings

The Pisco earthquake of August 15, 2007 resulted in 519 deaths and 1366 injured, with a total of 650,000 people affected and 80,000 dwellings damaged. Preliminary reports indicated that significant earthen sites were damaged. A few months after the earthquake a rapid assessment to better understand the failure of the affected sites was performed by a multidisciplinary team convened by the Getty Conservation Institute (GCI) in response to a request from the Instituto Nacional de Cultura del Perú (INC). This paper presents the highlights of that evaluation and its implications for the future design and retrofit of earthen buildings.

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Design Principles: Literature Review, Analysis, and Future Directions

Journal of Mechanical Design ◽

10.1115/1.4034105 ◽

2016 ◽

Vol 138 (10) ◽

Cited By ~ 25

Author(s):

Katherine K. Fu ◽

Maria C. Yang ◽

Kristin L. Wood

Keyword(s):

Design Science ◽

Design Principles ◽

Grand Challenge ◽

Formal Approach ◽

Design Problems ◽

Future Directions ◽

Future Design ◽

The Future ◽

Tools And Techniques ◽

Archival Practices

Design principles are created to codify and formalize design knowledge so that innovative, archival practices may be communicated and used to advance design science and solve future design problems, especially the pinnacle, wicked, and grand-challenge problems that face the world and cross-cutting markets. Principles are part of a family of knowledge explication, which also include guidelines, heuristics, rules of thumb, and strategic constructs. Definitions of a range of explications are explored from a number of seminal papers. Based on this analysis, the authors pose formalized definitions for the three most prevalent terms in the literature—principles, guidelines, and heuristics—and draw more definitive distinctions between the terms. Current research methods and practices with design principles are categorized and characterized. We further explore research methodologies, validation approaches, semantic principle composition through computational analysis, and a proposed formal approach to articulating principles. In analyzing the methodology for discovering, deriving, formulating, and validating design principles, the goal is to understand and advance the theoretical basis of design, the foundations of new tools and techniques, and the complex systems of the future. Suggestions for the future of design principles research methodology for added rigor and repeatability are proposed.

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Structural Performance of Automated Multi-Depth Shuttle Warehouses (Amsws) Under Low-to-Moderate Seismic Actions

10.21203/rs.3.rs-351252/v1 ◽

2021 ◽

Author(s):

Aleksei Kondratenko ◽

Alper Kanyilmaz ◽

Carlo Andrea Castiglioni ◽

Francesco Morelli ◽

Mohsen Kohrangi

Keyword(s):

Seismic Design ◽

Brittle Failure ◽

Structural Characteristics ◽

Time History ◽

Steel Structures ◽

Current Approach ◽

Structural Performance ◽

Future Design ◽

The Future ◽

Base Connections

Abstract Automated Multi-Depth Shuttle Warehouses (AMSWs) are compact storage systems that provide a large surface occupation and therefore maximum storage density. AMSWs represent the future of storage technology, providing substantial savings in terms of cost, space, and energy with respect to traditional warehouses. Currently, designers refer to the standard building codes for the seismic design of AMSWs. Since structural characteristics of AMSWs are considerably different from the steel structures of typical buildings, this current approach used by designers is questionable in terms of safety and efficiency. In this article, the behavior of 5 AMSW structures has been studied performing 150 time-history analyses by direct integration including P-Delta effects. Demand/capacity ratios calculated for each element showed the dominance of the brittle failure mechanism in AMSWs subjected to low-to-moderate seismic actions. These mechanisms mainly took place in upright columns and their base connections prior to the activation of ductile energy dissipation mechanisms of the structure. Based on the results, further improvements have been recommended for the future design provisions, which may lead to a safer seismic design of AMSWs.

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Affordances and tensions in recording bird observations: how coordinators and volunteers perceive and experience citizen science in birding

Journal of Science Communication ◽

10.22323/2.20020210 ◽

2021 ◽

Vol 20 (02) ◽

pp. A10

Author(s):

Helen Verploegen ◽

Wessel Ganzevoort ◽

Riyan van den Born

Keyword(s):

Qualitative Methods ◽

Data Sharing ◽

Citizen Science ◽

Qualitative Interviews ◽

Future Design ◽

Science Projects ◽

The Future

Digital citizen science projects differ greatly in their goals and design. Tensions arise when coordinators' design choices and conceptions of citizen science conflict with users' motivations and expectations. In this paper, we use a combination of qualitative methods to gain new insights into the ways citizen science is understood and implemented digitally. This includes a study into the affordances of two citizen science portals for bird observations, and qualitative interviews with users and coordinators of the portals. This reveals tensions related to data sharing, community hierarchies, and communicated expectations. Awareness of these tensions can benefit the future design of online citizen science projects.

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