On Almost Regular Mappings

Ioffe's criterion and various reformulations of it have become a~standard tool in proving theorems guaranteeing various regularity properties such as metric regularity, i.e., the openness with a linear rate around the reference point, of a~(set-valued) mapping. We derive an analogue of it guaranteeing the almost openness with a linear rate of mappings acting in incomplete spaces and having non-closed graphs, in general. The main tool used is an approximate version of Ekeland's variational principle for a function that is not necessarily lower semi-continuous and is defined on an abstract (possibly incomplete) space. Further, we focus on the stability of this property under additive single-valued and set-valued perturbations.Comment: 23 page

Modes of Flavin-Based Catalysis

Flavin derivatives participate in various chemical transformations in natural and artificial systems. The unique flavin versatility resulted in the development of many different bio-, organo-, and photocatalytic processes. This chapter draws attention to the ways in which members of the flavin family are involved in catalysis, regardless of whether the reactions take place in enzymes or in artificial catalytic systems. Both light-dependent transformations as well as processes occurring in the absence of light are involved.</p

Flavin-Based Catalysis - Preface

Participationincatalyticprocessesisoneofthemainrolesofflavins.Naturehasbeenusing this concept for millions of years. The discovery, description of the structureand function of flavins in the late nineteenth and first half of the twentieth cen-tury has triggered exploitation of the catalytic capabilities of flavins in man-madesynthetic transformations, either using enzymatic or artificial systems. Nowadays,flavins and flavoproteins are enjoying an increased interest from a broad audience,which includes researchers active in synthetic chemistry, enzymology, biocatalysis,and spectroscopy. With new natural flavins still being discovered in recent years,newflavoenzymestructuresandmechanismselucidated,newflavinderivativessyn-thesized, and new photocatalytic and biomimetic approaches developed, it is a verydynamicfieldofresearch.Evenifthemostcommonflavincofactorswerediscoveredabout one century ago, the field is alive and kicking. There are more than 1000 newscientific literature contributions on flavin-related research per year. Many of themare relevant to catalysis. Considering the increasing frequency of new discoveries, one may ask: Are there any limits to flavin catalysis

Flavin-Based Catalysis - Preface

Participationincatalyticprocessesisoneofthemainrolesofflavins.Naturehasbeenusing this concept for millions of years. The discovery, description of the structureand function of flavins in the late nineteenth and first half of the twentieth cen-tury has triggered exploitation of the catalytic capabilities of flavins in man-madesynthetic transformations, either using enzymatic or artificial systems. Nowadays,flavins and flavoproteins are enjoying an increased interest from a broad audience,which includes researchers active in synthetic chemistry, enzymology, biocatalysis,and spectroscopy. With new natural flavins still being discovered in recent years,newflavoenzymestructuresandmechanismselucidated,newflavinderivativessyn-thesized, and new photocatalytic and biomimetic approaches developed, it is a verydynamicfieldofresearch.Evenifthemostcommonflavincofactorswerediscoveredabout one century ago, the field is alive and kicking. There are more than 1000 newscientific literature contributions on flavin-related research per year. Many of themare relevant to catalysis. Considering the increasing frequency of new discoveries, one may ask: Are there any limits to flavin catalysis

Flavin-Based Catalysis - Preface

Participationincatalyticprocessesisoneofthemainrolesofflavins.Naturehasbeenusing this concept for millions of years. The discovery, description of the structureand function of flavins in the late nineteenth and first half of the twentieth cen-tury has triggered exploitation of the catalytic capabilities of flavins in man-madesynthetic transformations, either using enzymatic or artificial systems. Nowadays,flavins and flavoproteins are enjoying an increased interest from a broad audience,which includes researchers active in synthetic chemistry, enzymology, biocatalysis,and spectroscopy. With new natural flavins still being discovered in recent years,newflavoenzymestructuresandmechanismselucidated,newflavinderivativessyn-thesized, and new photocatalytic and biomimetic approaches developed, it is a verydynamicfieldofresearch.Evenifthemostcommonflavincofactorswerediscoveredabout one century ago, the field is alive and kicking. There are more than 1000 newscientific literature contributions on flavin-related research per year. Many of themare relevant to catalysis. Considering the increasing frequency of new discoveries, one may ask: Are there any limits to flavin catalysis

Flavin-Based Catalysis - Preface

Participationincatalyticprocessesisoneofthemainrolesofflavins.Naturehasbeenusing this concept for millions of years. The discovery, description of the structureand function of flavins in the late nineteenth and first half of the twentieth cen-tury has triggered exploitation of the catalytic capabilities of flavins in man-madesynthetic transformations, either using enzymatic or artificial systems. Nowadays,flavins and flavoproteins are enjoying an increased interest from a broad audience,which includes researchers active in synthetic chemistry, enzymology, biocatalysis,and spectroscopy. With new natural flavins still being discovered in recent years,newflavoenzymestructuresandmechanismselucidated,newflavinderivativessyn-thesized, and new photocatalytic and biomimetic approaches developed, it is a verydynamicfieldofresearch.Evenifthemostcommonflavincofactorswerediscoveredabout one century ago, the field is alive and kicking. There are more than 1000 newscientific literature contributions on flavin-related research per year. Many of themare relevant to catalysis. Considering the increasing frequency of new discoveries, one may ask: Are there any limits to flavin catalysis

Variational Analysis and Generalized Equations in Electronics

International audienceThe paper is devoted to the study of the Aubin/Lipschitz-like property and the isolated calmness of a particular non-monotone generalized equation arising in electronics. The variational and non-smooth analysis is applied in the theory of non-regular electrical circuits involving electronic devices like ideal diodes, practical diodes, DIACs, silicon controlled rectifiers (SCR), and transistors. We also discuss the relationship of our results to the ones using classical techniques from (smooth) analysis and provide a simulation for several simple electrical circuits which are chosen in order to cover the most common non-smooth elements in electronics. The simulations of the electrical circuits discussed in this paper are performed by using Xcos (a component of Scilab)

Newton's Method for Solving Inclusions Using Set-Valued Approximations

International audienceResults on stability of both local and global metric regularity under set-valued perturbations are presented. As an application, we study (super)linear convergence of a Newton- type iterative process for solving generalized equations. We investigate several iterative schemes such as the inexact Newton’s method, the nonsmooth Newton’s method for semismooth functions, the inexact proximal point algorithm, etc. Moreover, we also cover a forward-backward splitting algorithm for finding a zero of the sum of two multivalued (not necessarily monotone) operators. Finally, a globalization of the Newton’s method is discussed

Impact of oscillation parameters on surface quality of cast billets

The paper is focused on impact of different oscillation parameters on surface quality of peritectic steel grades cast into billets 150x150 mm. Hydraulic oscillation used for this purpose was temporarily installed on one strand of the billet caster. Hydraulic oscillation enables, in comparison to ordinary used electromechanical oscillation, flexible set-up of basic parameters of the oscillation cycle (negative strip time and its ratio). Proper oscillation mode is capable to assure regular oscillation marks development, good lubrication in the mould and adequate compression of the solidifying shell. Impact of an oscillation mode providing negative strip time 0.085 s and its ratio -50 % on surface quality of cast billets is compared with standard oscillation mode applied on strands equipped with electromechanical oscillation characterized with variable negative strip time between 0.084 and 0.096 s and fixed negative strip ratio to -14 %.Web of Science61128728

5-Ethyl-4a-meth­oxy-1,3-dimethyl-4a,5-dihydro­benzo[g]pteridine-2,4(1H,3H)dione

The title compound, C15H18N4O3, was formed by the reaction of methanol with 5-ethyl-1,3-dimethyl­alloxazinium perchlorate. Its structure mimics those of possible flavin inter­mediates in flavoenzymes. The heterocyclic rings are substituted with methyl, ethyl and meth­oxy groups. The central tricyclic skeleton is bent due to the presence of an sp 3 C atom. There are weak inter­molecular C—H⋯O inter­actions in the structure, forming a three-dimensional network