bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ringversuch zur Ermittlung des Chlorideindringwiderstands von Mörtel und Beton
Authors: Schulze Joachim , Breit Wolfgang 
Published: February 2018

AbstractIn dem im Rahmen des DAfStb‐Forschungsprojekts V488 durchgeführten Ringversuch zur Bestimmung des Chloridmigrationskoeffizienten wurden neben einem Instandsetzungsmörtel, der sowohl händisch (PCC) als auch im Spritzverfahren (SPCC) verarbeitet werden kann, ein Vergussbeton C80/95 mit hoher Gefügedichtigkeit und ein Normalbeton C20/25 mit geringer Gefügedichtigkeit untersucht. Hierdurch wurde die Untersuchung von stark variierenden Chloridmigrationskoeffizienten ermöglicht. Die Prüfinstitute erhielten Bohrkerne der jeweiligen Produkte und führten daran Untersuchungen in Anlehnung an die derzeit gültigen Regelwerke durch. Die Ergebnisse zeigten, dass das Eindringverhalten von Chloriden in Mörtel und Beton mit unterschiedlichen Gefügedichtigkeiten mit ausreichender Präzision beurteilt werden konnte. Die Prüfstreuung des Verfahrens zur Bestimmung des Chloridmigrationskoeffizienten, ermittelt aus den Wiederhol‐ und Vergleichsvariationskoeffizienten der teilnehmenden Prüfinstitute, lag tendenziell unterhalb der im BAW‐Merkblatt „Chlorideindringwiderstand von Beton“ aufgeführten Präzisionsdaten (Wiederholpräzision 11 % und Vergleichspräzision 20 %) und wies somit eine höhere Präzision auf. Eine Zuordnung der untersuchten Instandsetzungsmörtel und Betone hinsichtlich den Anforderungen an den Chlorideindringwiderstand nach BAW‐Merkblatt bezüglich der Expositionsklassen XS1–XS3 und XD1–XD3 kann mit ausreichender Sicherheit erfolgen.
Systematic review of measurement tools to assess surgeons' intraoperative cognitive workload
Authors: Dias R D , Ngo-Howard M C , Boskovski M T , Zenati M A , Yule S J 
Published: February 2018

Abstract

Background
Surgeons in the operating theatre deal constantly with high-demand tasks that require simultaneous processing of a large amount of information. In certain situations, high cognitive load occurs, which may impact negatively on a surgeon's performance. This systematic review aims to provide a comprehensive understanding of the different methods used to assess surgeons' cognitive load, and a critique of the reliability and validity of current assessment metrics.

Methods
A search strategy encompassing MEDLINE, Embase, Web of Science, PsycINFO, ACM Digital Library, IEEE Xplore, PROSPERO and the Cochrane database was developed to identify peer-reviewed articles published from inception to November 2016. Quality was assessed by using the Medical Education Research Study Quality Instrument (MERSQI). A summary table was created to describe study design, setting, specialty, participants, cognitive load measures and MERSQI score.

Results
Of 391 articles retrieved, 84 met the inclusion criteria, totalling 2053 unique participants. Most studies were carried out in a simulated setting (59 studies, 70 per cent). Sixty studies (71 per cent) used self-reporting methods, of which the NASA Task Load Index (NASA-TLX) was the most commonly applied tool (44 studies, 52 per cent). Heart rate variability analysis was the most used real-time method (11 studies, 13 per cent).

Conclusion
Self-report instruments are valuable when the aim is to assess the overall cognitive load in different surgical procedures and assess learning curves within competence-based surgical education. When the aim is to assess cognitive load related to specific operative stages, real-time tools should be used, as they allow capture of cognitive load fluctuation. A combination of both subjective and objective methods might provide optimal measurement of surgeons' cognition.
Solution Synthesis ofN,N‐Dimethylformamide‐Stabilized Iron‐Oxide Nanoparticles as an Efficient and Recyclable Catalyst for Alkene Hydrosilylation
Authors: Azuma Ryusei , Nakamichi Seiya , Kimura Jungo , Yano Hiroki , Kawasaki Hideya , Suzuki Takeyuki , Kondo Ryota , Kanda Yasuharu , Shimizu Ken‐ichi , Kato Kazuo , Obora Yasushi 
Published: February 2018

AbstractHighly activated, monodispersedN,N‐dimethylformamide (DMF)‐stabilized iron‐oxide nanoparticles (Fe2O3NPs) were synthesized by using iron(III) acetylacetonate as a precursor under open‐air conditions. The resulting Fe2O3NPs were characterized by various techniques (e.g., transmission electron microscopy, dynamic light scattering, X‐ray diffraction, X‐ray photoelectron spectroscopy, FTIR spectroscopy, and X‐ray adsorption near‐edge structure). The Fe2O3NPs exhibited efficient catalytic activity for the hydrosilylation of alkenes without the need for further additives. An effective recycling process of the colloidal catalyst by extraction with a hexane/DMF system was developed, and recycling of the catalyst over five cycles did not result in any significant loss in catalytic activity.
Quality Analysis of Liquid‐Filled Crystalline Containers
Authors: Wellner Martha , Ulrich Joachim 
Published: February 2018

AbstractCrystallization can be used for encapsulation in the pharmaceutical and food industries. In previous studies, the encapsulation of certain amounts of liquids was shown to be feasible, and crystalline container systems with milk or condensed milk as a filling were developed. Here, methods for quality analyses were investigated, with special focus on mechanical, chemical, thermodynamic, and kinetic properties. Mechanical stability was determined by employing a stability measurement device (crushing force). The pH values of the encapsulated liquids over time give only a rough idea of the shelf life. Investigating the mass loss is a suitable method as it allows conclusions concerning the level of permeability of the containers. The dissolvability and release time of the liquid can be determined via UV‐vis photometry.
Projection to latent structures with orthogonal constraints for metabolomics data
Authors: Stocchero Matteo , Riccadonna Samantha , Franceschi Pietro 
Published: February 2018

AbstractMultivariate techniques based on projection methods such as Principal Component Analysis and Partial Least Squares (PLS) regression are widely applied in metabolomics. However, the effects of confounding factors and the presence of specific clusters in the data could force the projection to produce inefficient representations in the latent space, preventing the identification of the most relevant data variation. To overcome this issue, we introduce a general framework for projection methods, allowing an easy integration of orthogonal constraints, which help in reducing the effect of uninformative variations. In particular, the discussed algorithms address different scenarios. When known confounding factors can be explicitly encoded into a proper constraint matrix, orthogonally Constrained Principal Component Analysis (oCPCA) and orthogonally Constrained PLS2 (oCPLS2) can be used. Orthogonal PLS (OPLS) and post‐transformation of PLS2 (ptPLS2), instead, are suited to problems in which a constraint matrix cannot be defined. Finally, a data integration task is considered: Orthogonal two‐block PLS (O2PLS) and Orthogonal Wold's two‐block Mode A PLS (OPLS‐W2A) are used to identify the common variation between two data sets.
Theory Uncovers the Role of the Methionine–Tyrosine–Tryptophan Radical Adduct in the Catalase Reaction of KatGs: O2 Release Mediated by Proton‐Coupled Electron Transfer
Authors: Wang Binju , Fita Ignacio , Rovira Carme 
Published: February 2018

AbstractCatalase–peroxidases (KatGs) are bifunctional enzymes exhibiting both peroxidase and substantial catalase activities. It is widely recognized from experiments that the catalatic activity of KatGs is correlated with a unique covalent adduct (M‐Y‐W) formed in the active site, but the exact role of this adduct was elusive up to now. Here, quantum mechanical/molecular mechanical (QM/MM) calculations and QM/MM metadynamics are employed to elucidate the molecular mechanism and the role of M‐Y‐W adduct in the catalase reaction. It is shown that O2 formation proceeds through a mechanism involving proton‐coupled electron transfer (PCET). The M‐Y‐W cation radical adduct, which is close to the heme, His112 and the HOO. radical intermediate, acts as an electron sink during the PCET process. The present study also highlights the structural differences and functional similarities between KatGs and monofunctional catalases.
Metal Cluster Models for Heterogeneous Catalysis: A Matrix‐Isolation Perspective
Authors: Hübner Olaf , Himmel Hans‐Jörg 
Published: February 2018

AbstractMetal cluster models are of high relevance for establishing new mechanistic concepts for heterogeneous catalysis. The high reactivity and particular selectivity of metal clusters is caused by the wealth of low‐lying electronically excited states that are often thermally populated. Thereby the metal clusters are flexible with regard to their electronic structure and can adjust their states to be appropriate for the reaction with a particular substrate. The matrix isolation technique is ideally suited for studying excited state reactivity. The low matrix temperatures (generally 4–40 K) of the noble gas matrix host guarantee that all clusters are in their electronic ground‐state (with only a very few exceptions). Electronically excited states can then be selectively populated and their reactivity probed. Unfortunately, a systematic research in this direction has not been made up to date. The purpose of this review is to provide the grounds for a directed approach to understand cluster reactivity through matrix‐isolation studies combined with quantum chemical calculations.
Bioconjugation with Thiols by Benzylic Substitution
Authors: Watanabe Kenji , Ohshima Takashi 
Published: February 2018

AbstractA benzylic substitution of 3‐indolyl(hydroxyl)acetate derivatives with thiols proceeded specifically in the presence of amino, carboxy, and phosphate groups in weakly acidic aqueous solutions under nearly physiological condition, while no reaction occurred at pH over 7. Kinetic studies revealed that the reaction followed second‐order kinetics (first‐order in the reactant and first‐order in thiol) in contrast with the SN1 mechanism of common benzylic substitution of alcohols. The utility of the present method for functionalization of biomacromolecules was demonstrated using several model proteins, such as lysozyme, insulin, trypsin, and serum albumin. The catalytic bioactivity of lysozyme in lysis of Micrococcus lysodeikticus cells was completely retained after the modification.
Stereoselective Transfer Semi‐Hydrogenation of Alkynes to E‐Olefins with N‐Heterocyclic Silylene–Manganese Catalysts
Authors: Zhou Yu‐Peng , Mo Zhenbo , Luecke Marcel‐Philip , Driess Matthias 
Published: February 2018

AbstractInvited for the cover of this issue is the group of Matthias Driess at the Technical University in Berlin. The image depicts the “catchy performance” conducted by the efficient silylene crab. Read the full text of the article at 10.1002/chem.201705745.
Production and Structural Analysis of Membrane‐Anchored Proteins in Phospholipid Nanodiscs
Authors: Raltchev Kolio , Pipercevic Joka , Hagn Franz 
Published: February 2018

AbstractStructural studies on membrane‐anchored proteins containing a transmembrane (TM) helix have been hampered by difficulties in producing these proteins in a natively folded form. Detergents that are required to solubilize the hydrophobic TM helix usually destabilize the soluble domain. Thus, TM helices are removed for structural studies, which neglects the pivotal role of a membrane on protein function. This work presents a versatile strategy for the production of this protein class attached to phospholipid nanodiscs. By inserting the TM‐helix into nanodiscs and a subsequent SortaseA‐mediated ligation of the soluble domain, membrane‐anchored BclxL could be obtained in a folded conformation. This strategy is suitable for high‐resolution structure determination as well as for probing membrane location by NMR. This method will be applicable to a wide range of membrane‐anchored proteins and will be useful to decipher their functional role in a native membrane environment.
Polydopamine‐Derived, In Situ N‐Doped 3D Mesoporous Carbons for Highly Efficient Oxygen Reduction
Authors: Qu Konggang , Wang Yinghua , Zhang Xianxi , Chen Hongyan , Li Haibo , Chen Baoli , Zhou Huawei , Li Dacheng , Zheng Yao , Dai Sheng 
Published: February 2018

AbstractN‐doped mesoporous carbons (NMCs) have drawn a lot of interest as alternative electrocatalysts to replace noble metals. The maximized surface areas endow NMCs substantially increased active sites and thus greatly promote the catalytically apparent performance. Herein, polydopamine (PDA) is employed to derive NMCs by a facile hard‐templating method. The newly‐developed NMC‐900 shows highly catalytic efficiency in oxygen reduction reaction (ORR), comparable to that of Pt/C and superb stability greatly surpassing Pt/C, attributed to its fascinating componential and structural merits. The componential‐favored graphitic N and pyridinic N afforded highly efficient and stable metal‐free active sites. The structurally large surface area (536 m2/g) and well‐aligned 3D mesoporous architecture provided sufficiently exposed active sites and unimpeded reaction channels for ORR. Both the good electrical conductivity and hydrophilic surface of NMC‐900 ensured an expedited ORR process.
Controlling the Outgrowth and Functions of Neural Stem Cells: The Effect of Surface Topography
Authors: Simitzi Chara , Karali Kanelina , Ranella Anthi , Stratakis Emmanuel 
Published: February 2018

AbstractNeural stem cells (NSCs) are self‐renewing cells that generate the major cell types of the central nervous system, namely neurons, astrocytes and oligodendrocytes, during embryonic development and in the adult brain. NSCs reside in a complex niche where they are exposed to a plethora of signals, including both soluble and physical signals such as compressive and shear stresses, but also discontinuities and differences in morphology of the extracellular environment, termed as topographical features. Different approaches that incorporate artificial micro‐ and nano‐scale surface topographical features have been developed aiming to recapitulate the in vivo NSC niche discontinuities and features, particularly for in vitro studies. The present review article aims at reviewing the existing body of literature on the use of artificial micro‐ and nano‐topographical features to control NSCs orientation and differentiation into neuronal and/or neuroglial lineage. The different approaches on the study of the underlying mechanism of the topography‐guided NSC responses are additionally revised and discussed.
Macrocycles Bearing Ferrocenyl Pendants and their Electrochemical Properties upon Binding to Divalent Transition Metal Cations
Authors: Zeng Zhanghua , Belousoff Matthew J. , Spiccia Leone , Bond Alan M. , Torriero Angel A. J. 
Published: February 2018

AbstractMetal complexes of Cu2+, Co2+, Cd2+, Zn2+, and Ni2+ formed with the ligands [Fc(cyclen)] (1) and [Fc(cyclen)2] (2) (Fc=ferrocene, cyclen=1,4,7,10‐tetraazacyclododecane) are synthesised and characterised. The X‐ray structure of the Cu2+ complex of 2, Fc([Cu(cyclen)(CH3CN)]2(ClO4)4, is reported, and shows that the two positively charged Cu2+‐cyclen units have a coordination number of five, adopting a distorted trigonal‐bipyramidal configuration. The Cu2+‐cyclen units are arranged in a trans‐like configuration with respect to the Fc group, presumably to minimise electrostatic repulsion. The voltammetric oxidation of the free ligands 1 and 2 in a CH2Cl2/CH3CN (1:4) solvent mixture yields two closely spaced oxidation processes. Both electron‐transfer steps are associated with the ferrocenyl moiety, implying strong communication between the cyclen nitrogen atoms and the ferrocenyl group. In contrast, cyclic voltammograms display only a simple reversible one‐electron process if 1 and 2 are complexed with Cd2+, Cu2+, Zn2+, Ni2+, or Co2+. Binding of these metal ions produces a significant shift in the reversible midpoint potential (Em). Except for Ni2+, Em is linearly proportional to the charge density of the transition metal ion, demonstrating that 1 and 2 may undergo redox switching. The diffusion coefficients of Fc, DmFc, 1 and 2, and their metal ion complexes correlate well with their molecular weights.
Electrical model of the alkaline electrolyser dedicated for SPICE
Authors: Górecki Krzysztof , Górecki Paweł , Zarębski Janusz 
Published: February 2018

SummaryIn this paper, properties of the alkaline electrolyser fed from the voltage source, producing the rectangular pulse train, were investigated. A model of this electrolyser for SPICE in the form of an electrical network was proposed. The structure of this electrical model was described, and the values of parameters of the model were presented. The correctness of this model was verified experimentally in a wide range of frequency. Using the worked out model, several characteristics of the electrolyser were calculated, and the influence of amplitude, frequency, and the duty factor of the supplying voltage on productivity and watt‐hour efficiency of the electrolysis process was discussed. The investigations were performed for 2 different concentration values of the KOH solution.
Development of an Image Processing Method for Automatic Inspection of Wear of Throw‐away Tips
Authors: WANG TING , CHEN YEN‐WEI , ISHIZAKI YOSHITOMO , MIYAMOTO MASARU , HATTORI TOMOHITO 
Published: February 2018

SUMMARYThe built‐in inspection is very important for quality control in precision cutting by throw‐away tip. We propose a new automatic inspection method for tool ware of industrial devices. We first do contrast enhancement of the ware image and then segment the cutting ware region by using Otsu thresholding method from the enhanced image. The area of the cutting ware region is used as a measure of cutting ware degree. Experimental results show that the proposed method is effective for automatic inspection of throw‐away tips in precision cutting.
CRT Survey II: a European Society of Cardiology survey of cardiac resynchronisation therapy in 11 088 patients—who is doing what to whom and how?
Authors: Dickstein Kenneth , Normand Camilla , Auricchio Angelo , Bogale Nigussie , Cleland John G. , Gitt Anselm K. , Stellbrink Christoph , Anker Stefan D. , Filippatos Gerasimos , Gasparini Maurizio , Hindricks Gerhard , Blomström Lundqvist Carina , Ponikowski Piotr , Ruschitzka Frank , Botto Giovanni Luca , Bulava Alan , Duray Gabor , Israel Carsten , Leclercq Christophe , Margitfalvi Peter , Cano Óscar , Plummer Chris , Sarigul Nedim Umutay , Sterlinski Maciej , Linde Cecilia 
Published: February 2018

BackgroundCardiac resynchronisation therapy (CRT) reduces morbidity and mortality in appropriately selected patients with heart failure and is strongly recommended for such patients by guidelines. A European Society of Cardiology (ESC) CRT survey conducted in 2008–2009 showed considerable variation in guideline adherence and large individual, national and regional differences in patient selection, implantation practice and follow‐up. Accordingly, two ESC associations, the European Heart Rhythm Association and the Heart Failure Association, designed a second prospective survey to describe contemporary clinical practice regarding CRT.Methods and resultsA survey of the clinical practice of CRT‐P and CRT‐D implantation was conducted from October 2015 to December 2016 in 42 ESC member countries. Implanting centres provided information about their hospital and CRT service and were asked to complete a web‐based case report form collecting information on patient characteristics, investigations, implantation procedures and complications during the index hospitalisation. The 11 088 patients enrolled represented 11% of the total number of expected implantations in participating countries during the survey period; 32% of patients were aged ≥75 years, 28% of procedures were upgrades from a permanent pacemaker or implantable cardioverter‐defibrillator and 30% were CRT‐P rather than CRT‐D. Most patients (88%) had a QRS duration ≥130 ms, 73% had left bundle branch block and 26% were in atrial fibrillation at the time of implantation. Large geographical variations in clinical practice were observed.Conclusion
CRT Survey II provides a valuable source of information on contemporary clinical practice with respect to CRT implantation in a large sample of ESC member states. The survey permits assessment of guideline adherence and demonstrates variations in patient selection, management, implantation procedure and follow‐up strategy.
Electrochemical Detection of As (III) on a Manganese Oxide‐Ceria (Mn2O3/CeO2) Nanocube Modified Au Electrode
Authors: Ren Baiyu , Sudarsanam Putla , Kandjani Ahmad Esmaielzadeh , Hillary Brendan , Amin Mohamad Hassan , Bhargava Suresh K. , Jones Lathe A. 
Published: February 2018

AbstractCeria cubes decorated with manganese oxide nanoparticles (Mn2O3/CeO2 nanocubes) were synthesized and used to modify a Au electrode for analysis of As(III) in aqueous solution. This modified electrode displayed improved sensitivity than either oxide on their own, indicating a synergistic effect due to the effect of Mn2O3 on the properties of CeO2. The improved sensitivity could be ascribed to the enhanced As (III) adsorption ability of Mn2O3/CeO2 nanocube during electrochemical pre‐concentration, combined with the well known As(III) sensing qualities of the gold substrate. The Mn2O3/CeO2 nanocube modified gold electrode behaved as a promising sensor with stable, repeatable square wave anodic stripping voltammetry (SWASV) peaks, separated from common interfering ions in natural water including Cu (II) under practical conditions. Repeatability and stability studies revealed the As (III) sensor to be robust and reliable, with a sensitivity of 0.0414 μA/ppb and a limit of detection (LoD) of 3.35 ppb under optimized conditions, indicating a possible general use of this class of heteronanostructures in electroanalytical chemistry for studies that rely upon adsorption of deposition of the analyte prior to stripping analysis.
Covalent Bonded Graphene/Neutral Red Nanocomposite Prepared by One‐step Electrochemical Method and its Electrocatalytic Properties Toward Uric Acid
Authors: Liu Chang , Xu Zhikun , Liu Ling 
Published: February 2018

AbstractA nanocomposite Graphene/Neutral Red (GNR) was fabricated via a facile electrochemical method by reducing graphene oxide (GO) and covalent bonding with NR on glassy carbon electrode (GCE) in one step. The bond between NR and graphene was characterized and demonstrated by X‐Ray Diffraction (XRD), X‐ray Photoelectron Spectroscopy (XPS), UV‐vis, Fourier Transform Infrared (FT‐IR). Electrochemical data revealed that the GNR resulted in a sensitivity enhancement of uric acid (UA) oxidation and CV curve shown that the catalytic oxidation current is linearly dependent on UA concentration in the range of 0.5–50 μM and 50 μM−2 mM with a detection limit of 0.076 μM (S/N=3). The existing ions and physiological interferents were tested and they were nearly negligible or have a very small influence. Moreover, 2 weeks stability was obtained. By compared with other UA sensor, the present method is simple than previous report and the performance is better.
Synthesis of thiophene derivatives with long‐lasting citrusy type odour
Authors: Kost Bartłomiej , Matysiak Sylwia , Kula Józef , Bonikowski Radosław 
Published: February 2018

AbstractStarting from 3‐methylthiophene, 11 new sensory‐active thiophene derivatives were synthesized. Among them, 3‐(5‐butyl‐3‐methylthiophen‐2‐yl)‐1‐methylpropyl acetate (3), 2,5‐dibutyl‐3‐methylthiophene, and 1‐methyl‐3‐(3‐methylthiophen‐2‐yl)propyl acetate (12) were characterized by long‐lasting citrus scents. The individual enantiomers of esters 3 and 12, which have been characterized in terms of fragrance, were also obtained.