bluuebunny/crossref_metadata_2025 huggingface dataset:
Root demotion: efficient post-processing of layered graphs to reduce dummy vertices for hierarchical graph drawing
Authors: Magruder Daniel Summer , Bonn Stefan
Published: October 2017

One of the most popular hierarchical graph drawing frameworks - the Sugiyama, Tagawa, and Toda (STT) framework - often introduces dummy vertices to the given directed acyclic graph as part of its methodology to produce the final drawing. The inclusion of dummy vertices increases the size of the input graph and consequently inflates the run time of the subsequent algorithms. Given that most graph drawing problems are NP-hard, good layering algorithms or efficient post-processing - which produces a minimal number of dummy vertices - restrain the increased run time. Many layering or layering post-processing algorithms have quadratic or cubic run time. Here we introduce Root Demotion, a linear time post-processing algorithm for the layering produced by the Longest-Path algorithm that reduces the number of dummy vertices required compared to current post-processing algorithms, consequently shortening the remaining run time of the STT framework.
Planarity of Overlapping Clusterings Including Unions of Two Partitions
Authors: Athenstädt Jan Christoph , Cornelsen Sabine
Published: October 2017

We consider clustered planarity with overlapping clusters as introduced by Didimo et al. (Didimo, Giordano, Liotta, JGAA, 2008). It can be deduced from a proof in Athenstädt et al. (J. C. Athenstädt, T. Hartmann, and M. Nöllenburg, GD 2014) that the problem is NP-complete, even if restricted to instances where the underlying graph is 2-connected, the set of clusters is the union of two partitions and each cluster contains at most two connected components while their complements contain at most three connected components.

In this paper, we show that clustered planarity with overlapping clusters can be solved in polynomial time if each cluster induces a connected subgraph. It can be solved in linear time if the set of clusters is the union of two partitions of the vertex set such that, for each cluster, both the cluster and its complement induce connected subgraphs.
Notes on the Evolution of Compulsory Conciliation in Canada
Authors: Williams C. Brian
Published: October 2017

The purpose of this paper is to review the historical evolution of the concept of compulsory conciliation in federal labor law, and to suggest some four features in its history which appear to have been overlooked in the literature on the subject.
Les transformations technologiques et le rôle de la Recherche en relations industrielles
Authors: Quinet Félix
Published: October 2017

L'auteur analyse la portée des transformations technologiques sur les techniques de négociations collectives et de relations industrielles de même que sur le contenu des conventions collectives. A ce sujet, il décrit quelques règlements patronaux-ouvriers d'importance. Puis il traite de l'évolution de la politique gouvernementale en ce qu'elle affecte les relations industrielles, décrivant en particulier le nouveau Service consultatif de la main-d'oeuvre, au Ministère fédéral du Travail. Il conclut en parlant des transformations technologiques et notre régime de relations industrielles.
Le marché des soins médicaux et l'organisation de la profession médicale
Authors: Boudreau Thomas-J.
Published: October 2017

L'auteur présente une analyse de la structure du marché des soins médicaux et du type d'organisation professionnelle qui paraît le mieux adapté à ce marché dans le contexte de l'évolution présente.
Political Culture and Christian Trade Unionism
Authors: Barnes Samuel
Published: October 2017

Belgian trade unionism has always intensely attracted industrial relations specialists because of some peculiarities in its structuring and functioning. The object of the following paper is to impart some knowledge about the history of pluralist Belgian trade unionism, its foundation and relationships it entertains at different levels: religious, political, ideological.
Le Québec, au point tournant de son histoire
Authors: Kierans Eric W.
Published: October 2017

L'auteur, en se plaçant dans l'optique très particulière de l'économiste, décrit d'abord les trois changements qui, selon lui, se produisent dans le Québec. Puis, il les examine de deux points de vue différents : d'une part, du point de vue de l'homme d'affaires d'expression française et, d'autre part, du point de vue des milieux d'affaires d'expression anglaise.
Labor Relations Boards
Authors: Cunningham W. B.
Published: October 2017

In this article, the author exposes a statement of the principles of judicial review of the actions of labour relations boards.
La grève de l'amiante
Authors: Charpentier Alfred
Published: October 2017

Dans le présent article, l'auteur fait une analyse complète des dossiers de la Commission des relations ouvrières portant les numéros 2158, 2276, 2296 et 2116, relatifs à la grève de l'amiante survenue en 1949 à Asbestos, à Thetford-les-Mines et autres endroits de la région.
Les formes actuelles du Progrès technique et la formation des travailleurs
Authors: Cardin Jean-Réal
Published: October 2017

Le présent travail a pour objet : a) de chercher à caractériser la nature des développements technologiques survenant dans les sociétés industrielles contemporaines et en indiquer les principales manifestations; b) de rechercher les conséquences de la nouvelle technologie sur le caractère de l'entreprise et sur la structure de l'emploi, et c) d'évaluer les exigences nouvelles que pose la technique moderne en matière de formation et de qualification de la main-d'oeuvre.
Automation, evolution or revolution
Authors: Deschênes Jean-Paul
Published: October 2017

In this article, the author analyses certain consequences of automation and its influence on university teaching and research.
L'influence extragène en matière de direction syndicale au Canada
Authors: Tremblay Louis-Marie
Published: October 2017

Le type de direction syndicale est un élément fondamental dans toute situation ouvrière. L'auteur propose une synthèse historique et caractérise l'apport étranger à la conduite des syndicats canadiens. De l'Angleterre ont été exportées les conceptions du Nouveau Modèle, et plus tard du Nouvel Unionisme. Cependant les Etats-Unis ont été les principaux pourvoyeurs. Parmi les courants américains, l'influence prédominante a émané des unions internationales de métier. D'autre part, au Canada, certains chefs naturels charismatiques ont profondément marqué les débuts du syndicalisme chrétien.
La participation du mouvement syndical américain à l'établissement de l'Organisation internationale du travail
Authors: Dale Léon
Published: October 2017

De toutes les institutions spécialisées consacrées à la collaboration entre les nations, l'Organisation internationale du travail est la plus vieille. Créée en 1919, au lendemain de la première guerre mondiale, elle est la seule qui a pu se maintenir, continuer son oeuvre et survivre à la Société des nations. L'auteur lève ici un coin du voile et montre un aspect assez peu connu de l'établissement de l'OIT en décrivant le rôle que le syndicalisme américain y a joué.
L'inspection des établissements industriels et des édifices publics (1885-1900)
Authors: Chartier Roger
Published: October 2017

Voici le premier d'une série de textes sur la législation québécoise du travail (et sur les services connexes du Ministère du travail) de 1885 à nos jours. Ces notes sans prétention pourront un jour servir à l'histoire méthodique des relations du travail au Québec.
Viols naturalistes : « commune histoire » ou « épouvantable aventure » ?
Authors: Pierre Chantal
Published: October 2017

On viole beaucoup dans le roman naturaliste. Mais ce qui est présenté comme une
fatalité de la condition féminine ne donne pas lieu dans la plupart des récits à de
véritables histoires. Contre le fait divers, les mélodrames, le roman-feuilleton, les romans
sentimentaux du xixe siècle, le naturalisme
désamorce le pathétique et les drames qui caractérisent la littérature du viol. Il s’agit en
effet de l’afficher comme « commune histoire », dont les conditions et les raisons relèvent
d’explications déterministes qui tendent finalement à soustraire le viol au scandale. Zola,
néanmoins, par une évolution qui lui est propre, retrouve au fil des Rougon-Macquart ce goût
du scandale et d’un viol « romanesque » qu’il s’efforce de formuler et d’évaluer dans des
montages scénaristiques parfois risqués.
Distinguishing Remobilized Ash From Erupted Volcanic Plumes Using Space‐Borne Multiangle Imaging
Authors: Flower Verity J. B. , Kahn Ralph A.
Published: October 2017

Volcanic systems are composed of a complex combination of ongoing eruptive activity and secondary hazards, such as remobilized ash plumes. Similarities in the visual characteristics of remobilized and erupted plumes, as imaged by satellite‐based remote sensing, complicate the accurate classification of these events. The stereo imaging capabilities of the Multiangle Imaging Spectroradiometer (MISR) were used to determine the altitude and distribution of suspended particles. Remobilized ash shows distinct dispersion, with particles distributed within ~1.5 km of the surface. Particle transport is consistently constrained by local topography, limiting dispersion pathways downwind. The MISR Research Aerosol retrieval algorithm was used to assess plume particle microphysical properties. Remobilized ash plumes displayed a dominance of large particles with consistent absorption and angularity properties, distinct from emitted plumes. The combination of vertical distribution, topographic control, and particle microphysical properties makes it possible to distinguish remobilized ash flows from eruptive plumes, globally.
Stratospheric Ozone Depletion: An Unlikely Driver of the Regional Trends in Antarctic Sea Ice in Austral Fall in the Late Twentieth Century
Authors: Landrum Laura L. , Holland Marika M. , Raphael Marilyn N. , Polvani Lorenzo M.
Published: October 2017

It has been suggested that recent regional trends in Antarctic sea ice might have been caused by the formation of the ozone hole in the late twentieth century. Here we explore this by examining two ensembles of a climate model over the ozone hole formation period (1955–2005). One ensemble includes all known historical forcings; the other is identical except for ozone levels, which are fixed at 1955 levels. We demonstrate that the model is able to capture, on interannual and decadal timescales, the observed statistical relationship between summer Amundsen Sea Low strength (when ozone loss causes a robust deepening) and fall sea ice concentrations (when observed trends are largest). In spite of this, the modeled regional trends caused by ozone depletion are found to be almost exactly opposite to the observed ones. We deduce that the regional character of observed sea ice trends is likely not caused by ozone depletion.
Active Tectonics Around Almaty and along the Zailisky Alatau Rangefront
Authors: Grützner C. , Walker R. T. , Abdrakhmatov K. E. , Mukambaev A. , Elliott A. J. , Elliott J. R.
Published: October 2017

The Zailisky Alatau is a >250 km long mountain range in Southern Kazakhstan. Its northern rangefront around the major city of Almaty has more than 4 km topographic relief, yet in contrast to other large mountain fronts in the Tien Shan, little is known about its Late Quaternary tectonic activity despite several destructive earthquakes in the historical record. We analyze the tectonic geomorphology of the rangefront fault using field observations, differential GPS measurements of fault scarps, historical and recent satellite imagery, meter‐scale topography derived from stereo satellite images, and decimeter‐scale elevation models from unmanned aerial vehicle surveys. Fault scarps ranging in height from ~2 m to >20 m in alluvial fans indicate that surface rupturing earthquakes occurred along the rangefront fault since the Last Glacial Maximum. Minimum estimated magnitudes for those earthquakes areM6.8–7. Radiocarbon dating results from charcoal layers in uplifted river terraces indicate a Holocene slip rate of ~1.2–2.2 mm/a. We find additional evidence for active tectonic deformation all along the Almaty rangefront, basinward in the Kazakh platform, and in the interior of the Zailisky mountain range. Our data indicate that the seismic hazard faced by Almaty comes from a variety of sources, and we emphasize the problems related to urban growth into the loess‐covered foothills and secondary earthquake effects. With our structural and geochronologic framework, we present a schematic evolution of the Almaty rangefront that may be applicable to similar settings of tectonic shortening in the mountain ranges of Central Asia.
Alteration of glucocorticoid receptors and exacerbation of inflammation during lytic cytomegalovirus infection in THP‐1 cells
Authors: Wang Shujun , Dou Yaling , Yang Hong , Ni Anping , Zhang Rui , Qian Jiaming
Published: October 2017

Cytomegalovirus (CMV) infection is associated with glucocorticoid resistance in ulcerative colitis (UC) and may exacerbate the disease course. However, the underlying pathogenicity remains unclear. The aim of this study was to explore possible underlying mechanisms during CMV latency and lytic infection in the human mononuclear cell line THP‐1. Latent and activated CMV infection cell models were established. We performed real‐time PCR and western blotting to examine changes in glucocorticoid receptors (GRs) during CMV latency and activation. Pro‐inflammatory and anti‐inflammatory cytokines were detected by ELISA. After UV‐inactivated CMV infection, GRs and cytokines were also examined. The expression of GRs was elevated in the reactivation group. An increased ratio of GR β/α and phosphorylation of GRα in the CMV reactivation group may explain refractory response to steroids. During CMV lytic infection, pro‐inflammatory cytokines IL‐6 and TNF‐α increased remarkably and anti‐inflammatory cytokine IL‐5 decreased, which may exacerbate UC. GR and cytokines were unchanged in the UV‐inactivated CMV infection group. Changes in the number and function of GRs may account for glucocorticoid resistance in CMV reactivation. The imbalance of pro‐ and anti‐inflammatory cytokines may be related to severe inflammation.
Fatigue‐Resistant Bioinspired Graphene‐Based Nanocomposites
Authors: Wan Sijie , Cheng Qunfeng
Published: October 2017

Graphene is an attractive building block for constructing functional materials of flexible electronic devices, due to its extraordinary mechanical and electrical properties. Up to now, large amounts of high‐performance graphene‐based nanocomposites are fabricated. However, the fatigue behavior of graphene‐based nanocomposites, a key parameter for flexible electronic devices, is rarely investigated. According to the fatigue mechanisms of thermosetting polymer composites, the fatigue resistance of graphene‐based nanocomposites can be significantly improved by effectively restricting the crack growth. Natural nacre demonstrates unique multisuppression of crack propagation, which is attributed to its sophisticated interfacial architecture over multiple length scales, resulting in remarkable fracture toughness. The crack suppression mechanisms corresponding to different interfacial design strategies within bioinspired graphene‐based nanocomposites (BGBNs) are summarized in this feature article. The static mechanical properties, electrical conductivity, and fatigue resistance of these BGBNs are compared and discussed. The synergistic effect from various interfacial interactions and building blocks is highlighted to serve as the guidance for constructing novel fatigue‐resistant BGBNs. The promising applications of fatigue‐resistant BGBNs in flexible electronic devices are reviewed, and several challenges and corresponding solutions are proposed. The perspective of fatigue‐resistant BGBNs for fundamental research and commercial application is depicted.
Guided Molecular Assembly on a Locally Reactive 2D Material
Authors: Warner Ben , Gill Tobias G. , Caciuc Vasile , Atodiresei Nicolae , Fleurence Antoine , Yoshida Yasuo , Hasegawa Yukio , Blügel Stefan , Yamada‐Takamura Yukiko , Hirjibehedin Cyrus F.
Published: October 2017

Atomically precise engineering of the position of molecular adsorbates on surfaces of 2D materials is key to their development in applications ranging from catalysis to single‐molecule spintronics. Here, stable room‐temperature templating of individual molecules with localized electronic states on the surface of a locally reactive 2D material, silicene grown on ZrB2, is demonstrated. Using a combination of scanning tunneling microscopy and density functional theory, it is shown that the binding of iron phthalocyanine (FePc) molecules is mediated via the strong chemisorption of the central Fe atom to the sp3‐like dangling bond of Si atoms in the linear silicene domain boundaries. Since the planar Pc ligand couples to the Fe atom mostly through the in‐plane d orbitals, localized electronic states resembling those of the free molecule can be resolved. Furthermore, rotation of the molecule is restrained because of charge rearrangement induced by the bonding. These results highlight how nanoscale changes can induce reactivity in 2D materials, which can provide unique surface interactions for enabling novel forms of guided molecular assembly.
The Palladium Acetate‐Catalyzed Microwave‐Assisted Hirao Reaction without an Added Phosphorus Ligand as a “Green” Protocol: A Quantum Chemical Study on the Mechanism
Authors: Keglevich György , Henyecz Réka , Mucsi Zoltán , Kiss Nóra Zs.
Published: October 2017

It was proved by our experiments that on microwave irradiation, the mono‐ or bidentate phosphorus ligands generally applied in the palladium(II)‐catalyzed P–C coupling reaction of aryl bromides and dialkyl phosphites or secondary phosphine oxides may be substituted by the excess of the >P(O)H reagent that exists under a tautomeric equilibrium. Taking into account that the reduction of the palladium(II) salt and the ligation of the palladium(0) so formed requires 3 equivalents of the P‐species for the catalyst applied in a quantity of 5–10%, all together, 15–30% of the P‐reagent is necessary beyond its stoichiometric quantity. In the coupling reaction of diphenylphosphine oxide, it was possible to apply diethyl phosphite as the reducing agent and as the P‐ligand. The reactivities of the diethyl phosphite and diphenylphosphine oxide reagents were compared in a competitive reaction. The mechanism and the energetics of this new variation of the Hirao reaction of bromobenzene with Y2P(O)H reagents (Y=EtO and Ph) was explored by quantum chemical calculations. The first detailed study on simple reaction models justified our assumption that, under the conditions of the reaction, the trivalent form of the >P(O)H reagent may serve as the P‐ligand in the palladium(0) catalyst, and shed light on the fine mechanism of the reaction sequence. The existence of the earlier described bis(palladium complex) {[H(OPh2P)2PdOAc]2} was refuted by high level theoretical calculations. This kind of complex may be formed only with chloride anions instead of the acetate anion. The interaction of palladium acetate and Y2P(O)H may result in only the formation of the [(HO)Y2P]2Pd complex that is the active catalyst in the Hirao reaction. The new variation of the Hirao reaction is of a more general value, and represents the greenest protocol, as there is no need for the usual P‐ligands. Instead, the >P(O)H reagent should be used in an excess of up to 30%. Hence, the costs and environmental burdens may be decreased.

magnified image
Vinylogous Nucleophiles Bearing the Endocyclic Double Bond in the Allylic Alkylation with Morita‐Baylis‐Hillman Carbonates
Authors: Kowalczyk Dorota , Albrecht Łukasz
Published: October 2017

This study demonstrates that vinylogous transfer of nucleophilicity in the allylic alkylation with Morita‐Baylis‐Hillman carbonates can be accomplished through the endocyclic double bond in 3‐cyano‐4‐methylcoumarins. The developed reaction provides a straightforward access to functionalized coumarin derivatives of biological and synthetic relevance. Target, highly functionalized products have been chemoselectively and efficiently obtained in very high yield (up to 98%) and with excellent enantioselectivity (up to 99.5:0.5 er).

magnified image
3D Hierarchical Core–Shell Nanostructured Arrays on Carbon Fibers as Catalysts for Direct Urea Fuel Cells
Authors: Senthilkumar N. , Gnana kumar G. , Manthiram A.
Published: October 2017

Bifunctional cobalt oxide (Co3O4) nanowire catalysts grown on carbon cloth (CC) fibers and their modification with nickel oxide (NiO) and manganese dioxide (MnO2) to produce core–shell nanoarchitectures are explored as catalysts for urea oxidation reaction and oxygen reduction reaction in direct urea fuel cells (DUFC). Based on a systematic electrochemical characterization of the catalyst, the as‐developed core–shell nanoarchitectures are optimized toward DUFC performance. Under alkaline conditions with an anion exchange membrane, the DUFC with a cell configuration of Co3O4@NiO(1:2)/CC(a|c)Co3O4@MnO2(1:2)/CC exhibits a maximum power density of 33.8 mW cm−2 with excellent durability for 120 h without any performance loss. Furthermore, the DUFC exhibits a maximum power density of 23.2 mW cm−2 with human urine as a fuel. These findings offer an approach to convert human waste into treasure.
Further consideration of the curvature of the Neandertal Femur
Authors: Chapman Tara , Sholukha Victor , Semal Patrick , Louryan Stéphane , Van Sint Jan Serge
Published: October 2017

Objectives

Neandertal femora are particularly known for having a marked sagittal femoral curvature. This study examined femoral curvature in Neandertals in comparison to a modern human population from Belgium by the use of three‐dimensional (3D) quadric surfaces modeled from the bone surface. 3D models provide detailed information and enabled femoral curvature to be analyzed in conjunction with other morphological parameters.

Materials and Methods

3D models were created from CT scans of 75 modern human femora and 7 Neandertal femora. Quadric surfaces (QS) were created from the triangulated surface vertices in all areas of interest (neck, head, diaphyseal shaft, condyles) extracted from previously placed anatomical landmarks. The diaphyseal shaft was divided into five QS shapes and curvature was measured by degrees of difference between QS shapes. Each bone was placed in a local coordinate system enabling each bone to be analyzed in the same way.

Results

The use of 3D quadric surface fitting allowed the distribution of curvature with similarly curved femora to be analyzed and the different patterns of curvature between the two groups to be determined. The Neandertals were shown to have a higher degree of femoral curvature and a more distal point of femoral curvature than the modern human population from Belgium.

Conclusions

Morphological aspects of the Neandertal femur are different from this modern human population although mainly seem unrelated to femoral curvature. The relative lack of correlations with other femoral bony morphological factors suggests femoral curvature variations may be related to other aspects.
Evolving Accelerated Amidation by SpyTag/SpyCatcher to Analyze Membrane Dynamics
Authors: Keeble Anthony H. , Banerjee Anusuya , Ferla Matteo P. , Reddington Samuel C. , Anuar Irsyad N. A. Khairil , Howarth Mark
Published: October 2017

SpyTag is a peptide that forms a spontaneous amide bond with its protein partner SpyCatcher. This protein superglue is a broadly useful tool for molecular assembly, locking together biological building blocks efficiently and irreversibly in diverse architectures. We initially developed SpyTag and SpyCatcher by rational design, through splitting a domain from a Gram‐positive bacterial adhesin. In this work, we established a phage‐display platform to select for specific amidation, leading to an order of magnitude acceleration for interaction of the SpyTag002 variant with the SpyCatcher002 variant. We show that the 002 pair bonds rapidly under a wide range of conditions and at either protein terminus. SpyCatcher002 was fused to an intimin derived from enterohemorrhagic Escherichia coli. SpyTag002 reaction enabled specific and covalent decoration of intimin for live cell fluorescent imaging of the dynamics of the bacterial outer membrane as cells divide.
Facile Supramolecular Processing of Carbon Nanotubes and Polymers for Electromechanical Sensors
Authors: Kim Chae Bin , Jeong Ki Beom , Yang Beom Joo , Song Jong‐Won , Ku Bon‐Cheol , Lee Seunghyun , Lee Seoung‐Ki , Park Chiyoung
Published: October 2017

We herein report a facile, cost‐competitive, and scalable method for producing viscoelastic conductors via one‐pot melt‐blending using polymers and supramolecular gels composed of carbon nanotubes (CNTs), diphenylamine (DP), and benzophenone (BP). When mixed, a non‐volatile eutectic liquid (EL) produced by simply blending DP with BP (1:1 molar ratio) enabled not only the gelation of CNTs (EL‐CNTs) but also the dissolution of a number of commodity polymers. To make use of these advantages, viscoelastic conductors were produced via one‐pot melt‐blending the EL and CNTs with a model thermoplastic elastomer, poly(styrene‐b‐butadiene‐b‐styrene) (SBS, styrene 30 wt %). The resulting composites displayed an excellent electromechanical sensory along with re‐mendable properties. This simple method using cost‐competitive EL components is expected to provide an alternative to the use of expensive ionic liquids as well as to facilitate the fabrication of novel composites for various purposes.
Multiple Evidenz für einen ungewöhnlichen Wechselwirkungsmodus zwischen Calmodulin und Orai‐Proteinen
Authors: Traxler Lukas , Rathner Petr , Fahrner Marc , Stadlbauer Michael , Faschinger Felix , Charnavets Tatsiana , Müller Norbert , Romanin Christoph , Hinterdorfer Peter , Gruber Hermann J.
Published: October 2017

Calmodulin (CaM) bindet an die meisten Zielproteine durch Umwickeln einer amphiphatischen α‐Helix. Das N‐terminale Ende von Orai‐Proteinen enthält ein solches konserviertes CaM‐Bindungssegment, der molekulare Bindungsmechanismus ist jedoch strittig. Hier wurden die Bindungsgleichgewichte, die entsprechenden Kinetiken sowie die Bindungskräfte zwischen einzelnen Calmodulinmolekülen und den konservierten Helices von Orai1 oder Orai3 untersucht. Die Resultate zeigten übereinstimmend eine schrittweise Bindung von zwei einzelnen Peptiden an die beiden Lappen von CaM. Eine Affinitätsteigerung wurde beobachtet, wenn zwei Orai‐Peptide an ihren C‐Termini entweder dimerisiert oder mit hoher lateraler Dichte immobilisiert wurden, wodurch die enge Nachbarschaft dieser N‐terminalen Helices in den nativen Orai‐Oligomeren nachgebildet wurde. Analoge Kontrollexperimente mit Myosin‐Leichtketten‐Kinase von glatten Muskelzellen zeigten nur die konventionelle 1:1‐Bindung und bestätigten die Beweiskraft unserer Methoden.
Double Catalytic Kinetic Resolution (DoCKR) of Acyclic anti‐1,3‐Diols: The Additive Horeau Amplification
Authors: Merad Jérémy , Borkar Prashant , Caijo Frédéric , Pons Jean‐Marc , Parrain Jean‐Luc , Chuzel Olivier , Bressy Cyril
Published: October 2017

The concept of a synergistic double catalytic kinetic resolution (DoCKR) as described in this article was successfully applied to racemic acyclic anti‐1,3‐diols, a common motif in natural products. This process takes advantage of an additive Horeau amplification involving two successive enantioselective organocatalytic acylation reactions, and leads to diesters and recovered diols with high enantiopurities. It was first developed with C2‐symmetrical diols and then further extended to non‐C2‐symmetrical anti diols to prepare useful chiral building blocks. The protocol is highly practical as it only requires 1 mol % of a commercially available organocatalyst and leads to easily separable products. This procedure was applied to the shortest reported total synthesis of (+)‐cryptocaryalactone, a natural product with anti‐germinative activity.
Phosphorylation‐Responsive Membrane Transport of Peptides
Authors: Peng Shu , Barba‐Bon Andrea , Pan Yu‐Chen , Nau Werner M. , Guo Dong‐Sheng , Hennig Andreas
Published: October 2017

Phosphorylation and dephosphorylation of peptides by kinases and phosphatases is essential for signal transduction in biological systems, and many diseases involve abnormal activities of these enzymes. Herein, we introduce amphiphilic calixarenes as key components for supramolecular, phosphorylation‐responsive membrane transport systems. Dye‐efflux experiments with liposomes demonstrated that calixarenes are highly active counterion activators for established cell‐penetrating peptides, with EC50 values in the low nanomolar range. We have now found that they can even activate membrane transport of short peptide substrates for kinases involved in signal transduction, whereas the respective phosphorylated products are much less efficiently transported. This allows regulation of membrane transport activity by protein kinase A (PKA) and protein kinase C (PKC), as well as monitoring of their activity in a label‐free kinase assay.
Selective Radical Fluorination of Tertiary Alkyl Halides at Room Temperature
Authors: Chen He , Liu Zhonglin , Lv Ying , Tan Xinqiang , Shen Haigen , Yu Hai‐Zhu , Li Chaozhong
Published: October 2017

Direct fluorination of tertiary alkyl bromides and iodides with Selectfluor is described. The halogen‐exchange fluorination proceeds efficiently in acetonitrile at room temperature under metal‐free conditions and exhibits a wide range of functional group compatibility. Furthermore, the reactions are highly selective in that alkyl chlorides and primary and secondary alkyl bromides remain intact. A radical mechanism is proposed for this selective fluorination.
O2 Activation on Ceria Catalysts—The Importance of Substrate Crystallographic Orientation
Authors: Yang Chengwu , Yu Xiaojuan , Heißler Stefan , Weidler Peter G. , Nefedov Alexei , Wang Yuemin , Wöll Christof , Kropp Thomas , Paier Joachim , Sauer Joachim
Published: October 2017

An atomic‐level understanding of dioxygen activation on metal oxides remains one of the major challenges in heterogeneous catalysis. By performing a thorough surface‐science study of all three low‐index single‐crystal surfaces of ceria, probably the most important redox catalysts, we provide a direct spectroscopic characterization of reactive dioxygen species at defect sites on the reduced ceria (110) and (100) surfaces. Surprisingly, neither of these superoxo and peroxo species was found on ceria (111), the thermodynamically most stable surface of this oxide. Applying density functional theory, we could relate these apparently inconsistent findings to a sub‐surface diffusion of O vacancies on (111) substrates, but not on the less‐closely packed surfaces. These observations resolve a long standing debate concerning the location of O vacancies on ceria surfaces and the activation of O2 on ceria powders.
CODH‐IV: A High‐Efficiency CO‐Scavenging CO Dehydrogenase with Resistance to O2
Authors: Domnik Lilith , Merrouch Meriem , Goetzl Sebastian , Jeoung Jae‐Hun , Léger Christophe , Dementin Sébastien , Fourmond Vincent , Dobbek Holger
Published: October 2017

CO dehydrogenases (CODHs) catalyse the reversible conversion between CO and CO2. Genomic analysis indicated that the metabolic functions of CODHs vary. The genome of Carboxydothermus hydrogenoformans encodes five CODHs (CODH‐I–V), of which CODH‐IV is found in a gene cluster near a peroxide‐reducing enzyme. Our kinetic and crystallographic experiments reveal that CODH‐IV differs from other CODHs in several characteristic properties: it has a very high affinity for CO, oxidizes CO at diffusion‐limited rate over a wide range of temperatures, and is more tolerant to oxygen than CODH‐II. Thus, our observations support the idea that CODH‐IV is a CO scavenger in defence against oxidative stress and highlight that CODHs are more diverse in terms of reactivity than expected.
Spectroscopic studies, structural characterization and electrochemical studies of two cobalt (III) complexes with tridentate hydrazone Schiff base ligands: Evaluation of antibacterial activities, DNA‐binding, BSA interaction and molecular docking
Authors: Fekri Roghayeh , Salehi Mehdi , Asadi Asadollah , Kubicki Maciej
Published: October 2017

Co(III) complexes of tridentate Schiff base ligands derived from N‐(2‐hydroxybenzylideneamino)benzamide (H2L1) and 2‐(2‐hydroxybenzylidene)hydrazine‐1‐carboxamide (H2L2) were synthesized and characterized using IR, Raman, 1H–NMR and UV–Vis spectroscopies. X‐ray single crystal structures of complexes 1 and 2 have also been determined, and it was indicated that these Co(III) complexes are in a distorted octahedral geometry. The cyclic voltammetry (CV) of the complexes indicates an irreversible redox behavior for both complexes 1 and 2. The antibacterial effects of the synthesized compounds have been tested by minimum inhibitory concentration and minimum bactericidal concentration methods, which suggested that the metal complexes exhibit better antibacterial effects than the ligands against Gram‐positive bacteria. The effects of the drug (drug  =  ligands and complexes) on bovine serum albumin (BSA) were examined using circular dichroism (CD) spectropolarimetry, and it was revealed that the BSA (BSA, as a carrier protein) secondary structure changed in the presence of the drug. Interaction of the drug with calf‐thymus DNA (CT‐DNA) was investigated by UV–Vis absorption, fluorescence emission, CV and CD spectroscopy. Binding constants were determined using UV–Vis absorption. The results indicated that the studied Schiff bases bind to DNA, with the hyperchromic effect and non‐intercalative mode in which the metal complexes are more effective than ligands. Furthermore, molecular docking simulation was used to obtain the energetic and binding sites for the interaction of the complexes with Mycobacterium tuberculosis enoyl‐acyl carrier protein reductase (InhA), and results showed that complex 1 has more binding energy.
Three‐dimensional coordination polymers based on trimethyltin cation with nicotinic and isonicotinic acids as anticancer agents
Authors: Etaiw Safaa El‐din H. , Fayed Tarek A. , El‐bendary Mohamed M. , Marie Hassan
Published: October 2017

Two new coordination polymers, namely [Me3Sn(INA)] (CP1) and [Me3Sn(NA)] (CP2), where INA = isonicotinic acid and NA = nicotinic acid, were characterized using infrared, UV–visible and NMR spectroscopies, thermogravimetric analysis and single‐crystal X‐ray analyses. The structure of CP1 consists of a one‐dimensional coordinated chain which is further extended creating a two‐dimensional layer via hydrogen bonds. The two‐dimensional layers propagate along the corresponding planes creating a three‐dimensional framework by hydrogen bonding and edge‐to‐face π–π stacking. The asymmetric unit of CP2 contains one tin atom and one NA ligand exhibiting 1:1 stoichiometry. The structure of CP2 extends through coordination bonds to form a one‐dimensional zigzag chain which further extends to create a three‐dimensional network via crossing chains and hydrogen bonds. The tin atoms acquire distorted trigonal bipyramid (TBPY‐5) geometry. CP1 and CP2 were designed to investigate their cytotoxic properties against various human cancer cell lines: hepatocellular carcinoma, mammary gland breast cancer, human prostate cancer and colorectal carcinoma. The compounds are good anticancer agents against the tested cell lines. Also they were screened for their antioxidant, anti‐haemolytic, antibacterial and antifungal activities.
Oil absorption performance of polymer/clay aerogel materials
Authors: Al‐Biloushi Mohammad I. , Milliman Henry , Gawryla Matthew D. , Schiraldi David A.
Published: October 2017

Oil absorption performance of aerogels produced from poly(amide‐imides), epoxies, and acrylic polymers were dependent upon freezing conditions, which in turn dictated solid state structures of these materials. Denser aerogels have less void space, and are more efficient at filling that space with oil, supporting the hypothesis that capillary spacing plays a vital role in determining oil absorption. Lower molecular weight epoxy‐based polymers produced aerogels with small capillary radii, again allowing increasing amounts of the liquid to penetrate between the aerogel layers. Aerogels produced from acrylic emulsions outperformed the other two systems tested in terms of volume per volume absorption. The initial difficulty with these materials, the fact that they still retain some hydrophilicy and absorb water, was overcome by simple post curing treatment, which was able to reduce water absorption to near zero levels. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45844.
Diving back in time: Extending historical baselines for yelloweye rockfish with Indigenous knowledge
Authors: Eckert Lauren E. , Ban Natalie C. , Frid Alejandro , McGreer Madeleine
Published: October 2017

Ocean systems, and the culturally and commercially important fishes that inhabit them, face growing threats. Increasingly, unconventional data sources are being used to inform fisheries research and management for data‐poor species.

Listed as a species of special concern in Canada, yelloweye rockfish (Sebastes ruberrimus) are vulnerable to exploitation, and have historical and cultural value to Indigenous people. In this study, Indigenous fishers of British Columbia, Canada, were interviewed and asked about observed changes to the body sizes (length) and abundance of this species over the last ~60 years, and the factors driving these changes. Their current and historical estimates of size and abundance were compared with current biological survey data.

Forty‐two semi‐directed interviews were carried out and 89% of respondents observed a decrease in yelloweye rockfish body sizes since the 1980s. The median historical (1950s–1980s) length was 84 cm, compared with the median modern (2010–2015) length of 46 cm. All but one respondent reported substantial decrease in yelloweye rockfish abundance since their earliest fishing experiences (1950s to1980s, depending on participant's age), with a third suggesting the change was most evident in the early 2000s, followed by the 1980s (21%) and 1990s (17%).

Sizes of modern yelloweye rockfish estimated by participants resembled estimates derived from ecological data recorded concurrently at the study region.

This study illustrates a repeatable method for using traditional and local knowledge to extend baselines for data‐poor species, and highlights the value of integrating Indigenous knowledge into fisheries research and management.
Sterol content in the artificial diet of Mythimna separata affects the metabolomics of Arma chinensis (Fallou) as determined by proton nuclear magnetic resonance spectroscopy
Authors: Guo Yi , Liu Chen‐xi , Zhang Li‐sheng , Wang Meng‐qing , Chen Hong‐yin
Published: October 2017

Insects cannot synthesize sterols and must obtain them from plants. Therefore, reducing plant sterol content or changing sterol type might be an effective pest control strategy. However, the impacts of these changes on pests’ natural predators remain unknown. Here, we fed artificial diets with reduced sterol content to Mythimna separata (Walker) (Lepidoptera: Noctuidae) and investigated the effects on its natural predator, Arma chinensis (Fallou) (Hemiptera: Pentatomidae). Reduced sterol content in M. separata (MS1, MS2, and MS5) was achieved by feeding them artificial diets prepared from a feed base subjected to one, two, or five cycles of sterol extractions, respectively. The content of most substances increased in A. chinensis (AC) groups feeding on MS2 and MS5. The content of eight substances (alanine, betaine, dimethylamine, fumarate, glutamine, glycine, methylamine, and sarcosine) differed significantly between the control (AC0) and treated (AC1, AC2, and AC5) groups. Metabolic profiling revealed that only AC5 was significantly distinct from AC0; the major substances contributing to this difference were maltose, glucose, tyrosine, proline, O‐phosphocholine, glutamine, allantoin, lysine, valine, and glutamate. Furthermore, only two metabolic pathways, that is, nicotinate and nicotinamide metabolism and ubiquinone and other terpenoid‐quinone biosynthesis, differed significantly between AC1 and AC5 and the control, albeit with an impact value of zero. Thus, the sterol content in the artificial diet fed to M. separata only minimally affected the metabolites and metabolic pathways of its predator A. chinensis, suggesting that A. chinensis has good metabolic self‐regulation with high resistance to sterol content changes.
Development of a Sensitive Microarray Platform for the Ranking of Galectin Inhibitors: Identification of a Selective Galectin‐3 Inhibitor
Authors: Dion Johann , Advedissian Tamara , Storozhylova Nataliya , Dahbi Samir , Lambert Annie , Deshayes Frédérique , Viguier Mireille , Tellier Charles , Poirier Françoise , Téletchéa Stéphane , Dussouy Christophe , Tateno Hiroaki , Hirabayashi Jun , Grandjean Cyrille
Published: October 2017

Glycan microarrays are useful tools for lectin glycan profiling. The use of a glycan microarray based on evanescent‐field fluorescence detection was herein further extended to the screening of lectin inhibitors in competitive experiments. The efficacy of this approach was tested with 2/3′‐mono‐ and 2,3′‐diaromatic type II lactosamine derivatives and galectins as targets and was validated by comparison with fluorescence anisotropy proposed as an orthogonal protein interaction measurement technique. We showed that subtle differences in the architecture of the inhibitor could be sensed that pointed out the preference of galectin‐3 for 2′‐arylamido derivatives over ureas, thioureas, and amines and that of galectin‐7 for derivatives bearing an α substituent at the anomeric position of glucosamine. We eventually identified a diaromatic oxazoline as a highly specific inhibitor of galectin‐3 versus galectin‐1 and galectin‐7.
Why run the risk? Motivation for offences by patients with substance use and antisocial personality disorders which they rated as most risky to their own well‐being
Authors: Thylstrup Birgitte , Hesse Morten
Published: October 2017

Background

Understanding motives for offending is important for the development and delivery of effective interventions.

Aims

To explore associations between variables with motivational implications and the offence committed in the past year rated by people with antisocial personality disorder and substance use disorder as putting them and their status at most risk.

Methods

Participants were 127 outpatients from a sample recruited for a pragmatic randomised controlled trial of an intervention for adults attending substance abuse treatment clinics in 13 municipalities in Denmark. Motives for offending were assessed on one occasion, using the Offending Motivation Questionnaire, aggression was assessed using the Buss–Perry Aggression Questionnaire and substance‐related problems, including mental state difficulties, were assessed using the Substance Use Risk Profile.

Results

Attributing offending to provocation, excitement or financial gain differed substantially by type of offence, whereas attribution of offending to compliance did not. Personality scale scores were associated with attributing offences to provocation, excitement or compliance but not with financial gain.

Conclusions

Motives for offending among substance users with antisocial personality disorder must be understood both in light of the type of offence and personality traits. Offending behaviour prevention strategies that draw on these distinctions, run in parallel to treatment for substance use, could improve reduction in recidivism. Copyright © 2017 John Wiley & Sons, Ltd.
Copper Photosensitizers Containing P^N Ligands and Their Influence on Photoactivity and Stability
Authors: Giereth Robin , Frey Wolfgang , Junge Henrik , Tschierlei Stefanie , Karnahl Michael
Published: October 2017

Driven by the intention to improve classic heteroleptic copper photosensitizers two novel Cu(I) complexes applying a hetero‐bidentate P^N ligand were prepared. A combined photophysical, electrochemical, and theoretical study gives insights into structure–activity relationships and revealed an increased absorptivity. Both complexes were tested for the light‐driven production of H2.
CaB2S4O16: A Borosulfate Exhibiting a New Structure Type with Phyllosilicate Analogue Topology
Authors: Bruns Jörn , Podewitz Maren , Schauperl Michael , Joachim Bastian , Liedl Klaus R. , Huppertz Hubert
Published: October 2017

The reaction of Ca(CO3) with H3BO3 in oleum (20 % SO3) yielded colorless single‐crystals of CaB2S4O16 (monoclinic, P21/c, a=5.5188(2), b=15.1288(6), c=13.2660(6) Å, β=92.88(1)°, V=1106.22(8) Å3). X‐ray single‐crystal structure analysis revealed a phyllosilicate‐analogue anionic sub‐structure, forming 2D infinite anionic layers, which exhibit an unprecedented arrangement of condensed twelve‐membered (zwölfer) and four‐membered (vierer) rings of corner‐shared (SO4) and (BO4) tetrahedra. Charge compensation is achieved by Ca2+ cations, residing exclusively above the centers of the twelve‐membered rings. DFT investigations on the solid‐state structure corroborate the experimental findings and allow for a detailed valuation of charge distribution within the anionic network and an assignment of vibrational frequencies.
Enantiopurity and absolute configuration determination of arene cis‐dihydrodiol metabolites and derivatives using chiral boronic acids
Authors: Boyd Derek R. , Sharma Narain D. , Goodrich Peter A. , Malone John F. , McConville Gareth , Harrison John S. , Stevenson Paul J. , Allen Christopher C.R.
Published: October 2017

The relative merits of the methods employed to determine enantiomeric excess (ee) values and absolute configurations of chiral arene and alkene cis‐1,2‐diol metabolites, including boronate formation, using racemic or enantiopure (+) and (−)‐2‐(1‐methoxyethyl)phenylboronic acid (MEPBA), are discussed. Further applications of: 1) MEPBA derived boronates of chiral mono‐ and poly‐cyclic arene cis‐dihydrodiol, cyclohex‐2‐en‐1‐one cis‐diol, heteroarene cis/trans‐2,3‐diol, and catechol metabolites in estimating their ee values, and 2) new chiral phenylboronic acids, 2‐[1‐methoxy‐2,2‐dimethylpropyl]phenyl boronic acid (MDPBA) and 2‐[1‐methoxy‐1‐phenylmethyl]phenyl boronic acid (MPPBA) and their advantages over MEPBA, as reagents for stereochemical analysis of arene and alkene cis‐diol metabolites, are presented.
Preventive effects of mouthguard use while sleeping on recurrent aphthous stomatitis: Preliminary interventional study
Authors: Tada Hidesuke , Fujiwara Natsumi , Tsunematsu Takaaki , Tada Yoshiko , Arakaki Rieko , Tamaki Naofumi , Ishimaru Naozumi , Kudo Yasusei
Published: October 2017

Recurrent aphthous stomatitis (RAS) is the most common inflammatory ulceration in the oral mucosa of otherwise healthy individuals and is often accompanied by severe pain. However, the etiology of RAS is not completely understood, and currently, no therapy can completely prevent RAS recurrence. In our clinical experience, we noticed that patients using a night guard, which is often used for bruxism treatment, did not develop RAS. Therefore, the aim of this study was to determine whether mouthguard use can suppress RAS development. The cohort of this interventional, prospective, single‐center, and self‐controlled study included 20 subjects who developed RAS at least once a month. The oral health of all the subjects was recorded for 60 days before and after intervention with a mouthguard. The average number of RAS incidences decreased from 5.5 to 1.0, the average days until healing decreased from 7.3 to 5.6, and the period with RAS decreased from 31.5 to 5.0 with mouthguard use. Mouthguard use may be beneficial for preventing RAS development.