bluuebunny/crossref_metadata_2025_split huggingface dataset:
From Sponges to Nanotubes: A Change of Nanocrystal Morphology for Acute‐Angle Bent‐Core Molecules
Authors: Gorecka Ewa , Vaupotič Nataša , Zep Anna , Pociecha Damian 
Published: September 2016

AbstractThe crystalline (B4) phase made of acute‐angle bent‐core molecules (1,7‐naphthalene derivatives), which exhibits an unusual, highly porous sponge‐like morphology, is presented. However, if grown in the presence of low‐weight mesogenic molecules, the same crystal forms nanotubes with a very high aspect ratio. The nanotubes become unstable upon increasing the amount of dopant molecules, and the sponge‐like morphology reappears. The phase is optically active, and the optical activity is an order of magnitude smaller than in the B4 phase made of conventional bent‐core molecules. The optical activity is related to the spatial inhomogeneity of the layered structure and is reduced due to the low apex angle and low tilt of the molecules. The arrangement of molecules within the layers was deduced from the bathochromic absorption shift in the B4 phase.
A Copper‐Catalyzed Decarboxylative Amination/Hydroamination Sequence: Switchable Synthesis of Functionalized Indoles
Authors: Li Tian‐Ren , Cheng Bei‐Yi , Wang Ya‐Ni , Zhang Mao‐Mao , Lu Liang‐Qiu , Xiao Wen‐Jing 
Published: September 2016

AbstractA copper‐catalyzed decarboxylative amination/hydroamination sequence of propargylic carbamates with various nucleophiles is described for the first time. It features an earth‐abundant metal catalyst, mild reaction conditions, and high efficiency. Further treatments of the resultant key intermediates using an acid or a base in one pot enable the controllable and divergent synthesis of two types of functionalized indoles. Moreover, experiments to demonstrate the synthetic potential of this methodology are performed.
Investigation of the binding of AuNPs–6‐mercaptopurine and the sensitive detection of 6‐mercaptopurine using resonance Rayleigh light scattering
Authors: Li Zhihong , Bi Shuyun , Wang Tianjiao , Wang Yu , Zhou Huifeng , Wu Jun 
Published: September 2016

AbstractA highly sensitive method for the detection of 6‐mercaptopurine (MP) by resonance Rayleigh light scattering (RLS) method was developed. Gold nanoparticles (AuNPs) were synthesized by a modified seed method and characterized using transmission electron microscopy (TEM). AuNPs were bound to MP via covalent bonding to form the MP–AuNPs complex, which increased the RLS intensity of MP at 347 nm (increased by 65.7%). Under optimum conditions, the magnitude of the enhanced RLS intensity for MP–AuNPs was proportional to MP concentration in the range 0.0681–1.702 μg mL−1. The linear regression equation was represented as follows: ΔIRLS = 9.31 + 82.42c (r = 0.9948). The limit of detection (LOD, 3σ) was 3.32 ng mL−1. The system was applied successfully to detect MP in pharmaceuticals. MP recoveries were 99.9–101.7% with a relative standard deviation (RSD) (n = 5) of 0.59–0.77% for three synthetic samples, and 97.5–110.0% with an RSD of 0.98–2.10% (n = 5) for tablet samples.
Differential inhibition of human erythrocyte acetylcholinesterase by polyphenols epigallocatechin‐3‐gallate and resveratrol. Relevance of the membrane‐bound form
Authors: Salazar Paula B. , de Athayde Moncorvo Collado Alejandro , Canal‐Martínez Verónica , Minahk Carlos J. 
Published: September 2016

AbstractThe activity of acetylcholinesterase (AChE) from human erythrocytes was tested in the presence of the phenolic compounds resveratrol and epigallocatechin‐3‐gallate (EGCG). Even though the stilbene barely changed this enzymatic activity, EGCG did inhibit AChE. Importantly, it preferentially acted on the membrane‐bound enzyme rather than on its soluble form. Actually, it was shown that this flavonoid may bind to the red blood cell membrane surface, which may improve the interaction between EGCG and AChE. Therefore, caution should be taken when screening AChE inhibitors. In fact, testing compounds with the soluble form of the enzyme may underestimate the activity of some of these potential inhibitors, hence it would be advisable not to use them as a sole model system for screening. Moreover, erythrocyte AChE is proposed as a good model for these enzymatic assays. © 2016 BioFactors, 43(1):73–81, 2017
Tailor‐made biocatalysts enzymes for the fine chemical industry in China
Authors: Jiang Yu , Tao Rongsheng , Yang Sheng 
Published: September 2016

AbstractThe Center of Industrial Biotechnology (CIBT) was established in Huzhou for fine chemicals in 2006 and CIBT Shanghai was founded for bulk chemicals in 2008. CIBT is a non‐profit organization under auspices of the Shanghai Institutes for Biological Sciences, Shanghai Branch of the Chinese Academy of Sciences (CAS) and Huzhou Municipal Government. CIBT is affiliated with the CAS, which enables it to take advantage of the rich R&D resources and support from CAS; yet CIBT operates as an independent legal entity. The goal of CIBT is to incubate industrial biotechnologies and accelerate the commercialization of these technologies with corporate partners in China.
Position selectivity in face‐sensitive visual cortex to facial and nonfacial stimuli: an fMRI study
Authors: Nichols David F. , Betts Lisa R. , Wilson Hugh R. 
Published: September 2016

AbstractBackgroundEvidence for position sensitivity in object‐selective visual areas has been building. On one hand, most of the relevant studies have utilized stimuli for which the areas are optimally selective and examine small sections of cortex. On the other hand, visual field maps established with nonspecific stimuli have been found in increasingly large areas of visual cortex, though generally not in areas primarily responsive to faces.MethodsfMRI was used to study the position sensitivity of the occipital face area (OFA) and the fusiform face area (FFA) to both standard rotating wedge retinotopic mapping stimuli and quadrant presentations of synthetic facial stimuli. Analysis methods utilized were both typical, that is, mean univariate BOLD signals and multivoxel pattern analysis (MVPA), and novel, that is, distribution of voxels to pattern classifiers and use of responses to nonfacial retinotopic mapping stimuli to classify responses to facial stimuli.ResultsPolar angle sensitivity was exhibited to standard retinotopic mapping stimuli with a stronger contralateral bias in OFA than in FFA, a stronger bias toward the vertical meridian in FFA than in OFA, and a bias across both areas toward the inferior visual field. Contralateral hemispheric lateralization of both areas was again shown using synthetic face stimuli based on univariate BOLD signals, MVPA, and the biased contribution of voxels toward multivariate classifiers discriminating the contralateral visual field. Classifiers based on polar angle responsivity were used to classify the patterns of activation above chance levels to face stimuli in the OFA but not in the FFA.ConclusionsBoth the OFA and FFA exhibit quadrant sensitivity to face stimuli, though the OFA exhibits greater position responsivity across stimuli than the FFA and includes overlap in the response pattern to the disparate stimulus types. Such biases are consistent with varying position sensitivity along different surfaces of occipito‐temporal cortex.
Two Opposing d‐Amino Acids Give Zigzag Hairpin Epitopes an Additional Kink to Create Antibody‐Selective Peptide Antigens
Authors: Schrimpf Andreas , Geyer Armin 
Published: September 2016

AbstractWe have developed peptides that are able to distinguish between subgroups of polyclonal antibodies. These β‐hairpin peptides act as conformational epitopes with specific shape and flexibility; they have been analyzed by NMR and CD spectroscopy, and have been shown to identify known disease markers. As a standalone mini β‐sheet, a hairpin is stabilized by alternating pairs of hydrogen‐bonded and non‐bonded amino acids on its two opposing peptide strands. A single d mutation disrupts this secondary structure, the correlated double‐d mutation of two opposing amino acids compensates for this destabilizing effect. The designed kink was introduced into both hydrogen‐bonded and ‐non‐bonded positions of an all‐l hairpin that is a known conformational epitope in molecular recognition. Our peptides enabled the discrimination of different human rheumatoid arthritis autoantibodies in an ELISA assay.
Exploring the Reactivity of α‐Lithiated Aryl Benzyl Ethers: Inhibition of the [1,2]‐Wittig Rearrangement and the Mechanistic Proposal Revisited
Authors: Velasco Rocío , Silva López Carlos , Nieto Faza Olalla , Sanz Roberto 
Published: September 2016

AbstractBy carefully controlling the reaction temperature, treatment of aryl benzyl ethers with tBuLi selectively leads to α‐lithiation, generating stable organolithiums that can be directly trapped with a variety of selected electrophiles, before they can undergo the expected [1,2]‐Wittig rearrangement. This rearrangement has been deeply studied, both experimentally and computationally, with aryl α‐lithiated benzyl ethers bearing different substituents at the aryl ring. The obtained results support the competence of a concerted anionic intramolecular addition/elimination sequence and a radical dissociation/recombination sequence for explaining the tendency of migration for aryl groups. The more favored rearrangements are found for substrates with electron‐poor aryl groups that favor the anionic pathway.
Enantioselective Organocatalytic Cascade Approach to Different Classes of Benzofused Acetals
Authors: Paz Bruno Matos , Klier Lydia , Næsborg Line , Lauridsen Vibeke Henriette , Jensen Frank , Jørgensen Karl Anker 
Published: September 2016

AbstractA novel enantioselective organocatalytic strategy is presented for the synthesis of tetrahydrofurobenzofuran and methanobenzodioxepine natural product core structures. The strategy is based on a pair of divergent reaction pathways in which hydroxyarenes react with γ‐keto‐α,β‐unsaturated aldehydes, catalyzed by a chiral secondary amine. One reaction pathway, which leads to chiral 5,5‐fused acetals with two stereocenters—the tetrahydrofurobenzofuran scaffolds—proceeds in moderate yields and up to 96 % ee. The other reaction pathway provides 5,6‐bridged methanobenzodioxepine scaffolds with three stereocenters in moderate to good yields and up to 95 % ee. The reaction is remarkable as it can proceed with catalyst loadings as low as 0.25 mol %, providing one of the highest known turnover numbers in iminium ion catalysis. Furthermore, the hemiacetal tetrahydrofurobenzofuran can undergo functionalizations including reduction, oxidation, and allylation. Finally, the effects involved in the substrate control for the divergent pathways, based on both experimental and computational studies, have been investigated. A model involving steric, electronic and stereoelectronic interactions is discussed to rationalize the observed selectivities.
Highly Axial Magnetic Anisotropy in a N3O5 Dysprosium(III) Coordination Environment Generated by a Merocyanine Ligand
Authors: Selvanathan Pramila , Huang Gang , Guizouarn Thierry , Roisnel Thierry , Fernandez‐Garcia Guglielmo , Totti Federico , Le Guennic Boris , Calvez Guillaume , Bernot Kévin , Norel Lucie , Rigaut Stéphane 
Published: September 2016

AbstractA spiropyran‐based switchable ligand isomerizes upon reaction with lanthanide(III) precursors to generate complexes with an unusual N3O5 coordination sphere. The air‐stable dysprosium(III) complex shows a hysteresis loop at 2 K and a very strong axial magnetic anisotropy generated by the merocyanine phenolate donor.
Mono‐ and Bimetallic Alkynyl Metallocenes and Half‐Sandwich Complexes: A Simple and Versatile Synthetic Approach
Authors: Valderas Carolina , Marzo Leyre , de la Torre María C. , García Ruano José Luis , Alemán José , Casarrubios Luis , Sierra Miguel A. 
Published: September 2016

AbstractA general process for the synthesis of alkynyl mono and dimetallic metallocenes and half‐sandwich complexes has been developed. This approach uses the addition of lithium derivatives of sandwich or half‐sandwich complexes to arylsulfonylacetylenes. The reaction occurs in two steps (lithiation and anti‐Michael addition to alkynylsulfone followed by elimination of the ArSO2 moiety) to form the corresponding mono‐ or bimetallic alkynes in clearly higher yields, simpler experimental procedures, and more environmentally benign conditions than those of the so far reported for the synthesis of this type of products. The electrochemical properties of the newly obtained complexes have also been studied.
Dynamische Methode zur Berechnung thermodynamischer Gleichgewichte in reaktiven Mehrphasensystemen
Authors: Zinser Alexander , Sundmacher Kai 
Published: September 2016

AbstractEin allgemeiner Ansatz zur Berechnung thermodynamischer Gleichgewichte für nichtreaktive und reaktive Mehrphasensysteme wird vorgestellt. Dieser basiert auf der Simulation der dynamischen Evolution eines Gemisches aus einem beliebigen Nichtgleichgewichtszustand in das thermodynamische Gleichgewicht hinein. Der Vorteil dieses Ansatzes ist, dass er komplexe Mehrkomponentensysteme behandeln kann, ohne numerische Schwierigkeiten zu bereiten. Die Anwendung der vorgestellten Methode wird anhand verschiedener Gleichgewichtssituationen des Stoffsystems der Butylacetat‐Synthese erläutert.
3D physiological model of the aortic valve incorporating small coronary arteries
Authors: Mohammadi Hossein , Cartier Raymond , Mongrain Rosaire 
Published: September 2016

AbstractThe diseases of the coronary arteries and the aortic root are still the leading causes of mortality and morbidity worldwide. In this study, a 3D global fluid‐structure interaction of the aortic root with inclusion of anatomically inspired small coronary arteries using the finite element method is presented. This innovative model allows to study the impact and interaction of root biomechanics on coronary hemodynamics and brings a new understanding to small coronary vessels hemodynamics. For the first time, the velocity profiles and shear stresses are reported in distal coronary arteries as a result of the aortic flow conditions in a global fluid‐structure interaction model.
Natural compounds and vegetable powders improve the stability and antioxidant properties of Brassica napus L. var. oleifera (rapeseed) oil
Authors: Tundis Rosa , Tenuta Maria Concetta , Loizzo Monica R. , Bonesi Marco , Menichini Francesco , Duthie Garry 
Published: September 2016

This work evaluated the strategies to increase the oxidative stability and the potential health benefits of Brassica napus L. var. oleifera (rapeseed) oil enriched with natural compounds. The effect of storage, light, and heating on the oxidative stability of rapeseed oil was compared with olive oil. Oxidative stability was assessed by using Rancimat and thiobarbituric acid reactive‐substances assay (TBARS) production. Different concentrations of individual phenol compounds, extracts, and vegetable powders were added to the cold‐pressed rapeseed oil. The most positive effects were observed with addition of freeze dried powders. The rapeseed oil chemical profile was analyzed by gas chromatography (GC) and gas chromatography‐mass spectrometry (GC‐MS) and the antioxidant effects of rapeseed oil fortified with vegetable powders were investigated with different in vitro assays. Results suggested that beetroot, carrot, tomato, and swede can offer effective alternatives or adjuncts to synthetic antioxidants during frying and storage of rapeseed oil.Practical applications: Brassica napus L. var. oleifera (rapeseed) oil is one of the most consumed oil. In this study, we evaluated the possible approaches to increase rapeseed oil oxidative stability and potential health benefits by using different natural products (beetroot, broccoli, carrot, celery, green pea, onion, red pepper, spinach, swede, tomato, and yellow pea). Results clearly showed that natural products may increase the stability of rapeseed oil, particularly when within a matrix rather than as an extract or pure compound. These evidences are significant for both consumers and oil industry.Rapeseed oil oxidative stability is investigated. Rapeseed oil composition is determined by GC‐MS. Increased antioxidant activity of rapeseed oil with powders supplementation is evidenced. Vegetable powders can offer effective alternative to synthetic antioxidants during frying and storage of rapeseed oil. Rapeseed oil oxidative stability is investigated. Rapeseed oil composition is determined by GC‐MS. Increased antioxidant activity of rapeseed oil with powders supplementation is evidenced. Vegetable powders can offer effective alternative to synthetic antioxidants during frying and storage of rapeseed oil.
Effect of Fe (III) on Pseudokirchneriella subcapitata at circumneutral pH in standard laboratory tests is explained by nutrient sequestration
Authors: Arbildua Jose J. , Villavicencio German , Urrestarazu Paola , Opazo Margaret , Brix Kevin V. , Adams William J. , Rodriguez Patricio H. 
Published: September 2016

Abstract

The complex chemistry of iron (Fe) at circumneutral pH in oxygenated waters and the poor correlation between ecotoxicity results in laboratory and natural waters have led to regulatory approaches for iron based on field studies (US Environmental Protection Agency Water Quality Criteria and European Union Water Framework Directive proposal for Fe). The results of the present study account for the observed differences between laboratory and field observations for Fe toxicity to algae (Pseudokirchneriella subcapitata). Results from standard 72-h assays with Fe at pH 6.3 and pH 8 resulted in similar toxicity values measured as algal biomass, with 50% effect concentrations (EC50) of 3.28 mg/L and 4.95 mg/L total Fe(III), respectively. At the end of the 72-h exposure, however, dissolved Fe concentrations were lower than 30 μg/L for all test concentrations, making a direct toxic effect of dissolved iron on algae unlikely. Analysis of nutrient concentrations in the artificial test media detected phosphorus depletion in a dose-dependent manner that correlated well with algal toxicity. Subsequent experiments adding excess phosphorus after Fe precipitation eliminated the toxicity. These results strongly suggest that observed Fe(III) toxicity on algae in laboratory conditions is a secondary effect of phosphorous depletion. Environ Toxicol Chem 2017;36:952–958. © 2016 SETAC
Assessment Capacity Building at a Research University
Authors: Stitt‐Bergh Monica 
Published: September 2016

AbstractHigher education institutions use program‐level learning outcomes assessment to improve programs, enhance student learning, and meet external requirements. An assessment office at a research university used a variety of evaluation capacity‐building (ECB) activities to increase faculty and administrators’ engagement in assessment and use of findings for program improvement. To investigate six desired ECB outcomes, the author analyzed survey responses and program assessment reports (2008–2014). The findings showed success in four ECB outcomes: positive attitudes toward assessment, motivation to engage, knowledge and skills, and department climate. However, two outcomes fell below expectations: department resources and use of findings. A correlation study revealed several significant, positive relationships between outcomes and faculty engagement with the strongest relationship being between level of faculty assessment experience and knowledge and skills. Because use of findings for program improvement and better student learning are primary assessment purposes, these results are valuable for campus planning of future capacity‐building activities. New ECB efforts that focus on faculty capacity to discuss assessment with colleagues, department resources, and most important, ways to use assessment findings are planned.
Synthesis, odour characteristics and antibacterial activities of the stereoisomeric forms of whisky lactone and its thiono analogues
Authors: Shimotori Yasutaka , Hoshi Masayuki , Okabe Hayato , Miyakoshi Tetsuo , Kanamoto Taisei , Nakashima Hideki 
Published: September 2016

AbstractFour stereoisomers of whisky lactone were selectively synthesized in over 99% enantiomeric excess using an amino acid derivative as a resolving agent. Cbz‐L‐proline was the most effective resolving agent, and both trans‐ and cis‐stereoisomers were comparatively easily separated. Odour characteristics of whisky thionolactone were different among four stereomeric isomers, and only (3S,4R)‐whisky thionolactone had mushroom and cis‐jasmone like note. Among all isomers, only (3R,4S)‐whisky lactone showed antibacterial activities against Staphylococcus aureus. Whisky thionolactone had higher activities than whisky lactone, and (3R,4S)‐whisky thionolactone showed the strongest activities of all tested samples. Copyright © 2016 John Wiley & Sons, Ltd.
Where are the limits of model predictive capabilities?
Authors: Refsgaard J.C. , Højberg A.L. , He X. , Hansen A.L. , Rasmussen S.H. , Stisen S. 
Published: September 2016

AbstractDistributed hydrological models can make predictions with much finer spatial resolution than the supporting field data. They will, however, usually not have a predictive capability at model grid scale due to limitations of data availability and uncertainty of model conceptualizations. In previous publications, we have introduced the Representative Elementary Scale (RES) concept as the theoretically minimum scale at which a model with a given conceptualization has a potential for obtaining a predictive accuracy corresponding to a given acceptable accuracy. The new RES concept has similarities to the 25‐year‐old Representative Elementary Area concept, but it differs in the sense that while Representative Elementary Area addresses similarity between subcatchments by sampling within the catchment, RES focuses on effects of data or conceptualization uncertainty by Monte Carlo simulations followed by a scale analysis. In the present paper, we extend and generalize the RES concept to a framework for assessing the minimum scale of potential predictability of a distributed model applicable also for analyses of different model structures and data availabilities. We present three examples with RES analyses and discuss our findings in relation to Beven's alternative blueprint and environmental modeling philosophy from 2002. While Beven here addresses model structural and parameter uncertainties, he does not provide a thorough methodology for assessing to which extent model predictions for variables that are not measured possess opportunities to have meaningful predictive accuracies, or whether this is impossible due to limitations in data and models. This shortcoming is addressed by the RES framework through its analysis of the relationship between aggregation scale of model results and prediction uncertainties and for considering how alternative model structures and alternative data availability affects the results. We suggest that RES analysis should be applied in all modeling studies that aim to use simulation results at spatial scales smaller than the support scale of the calibration data.