bluuebunny/crossref_metadata_2025_split huggingface dataset:
1,3‐Butadienyl Dianions as Non‐Innocent Ligands: Synthesis and Characterization of Aromatic Dilithio Rhodacycles
Authors: Wei Junnian , Zhang Yongliang , Zhang Wen‐Xiong , Xi Zhenfeng 
Published: July 2015

AbstractHerein we report that 1,4‐dilithio‐1,3‐butadienes, a type of 1,3‐butadienyl dianion, can act as non‐innocent ligands, taking electrons from low‐valent transition metals. Dilithio reagents reacted with [{RhCl(cod)}2] to give dilithio rhodacycle 3 a. Single‐crystal X‐ray structural analysis revealed the structure of 3 a with averaged bond lengths. XPS data suggested that the oxidation state of Rh in 3 a was more likely to be Rh3+. CDA/ECDA confirmed the electron‐transfer process. 7Li NMR spectra of 3 a and theoretical calculations revealed a considerable aromatic character. In this process, the dilithio compounds behaved as non‐innocent ligands and formal oxidants. These results demonstrated that organolithium compounds with suitable π‐conjugation could be used as electron acceptor.
A Native Ternary Complex Trapped in a Crystal Reveals the Catalytic Mechanism of a Retaining Glycosyltransferase
Authors: Albesa‐Jové David , Mendoza Fernanda , Rodrigo‐Unzueta Ane , Gomollón‐Bel Fernando , Cifuente Javier O. , Urresti Saioa , Comino Natalia , Gómez Hansel , Romero‐García Javier , Lluch José M. , Sancho‐Vaello Enea , Biarnés Xevi , Planas Antoni , Merino Pedro , Masgrau Laura , Guerin Marcelo E. 
Published: July 2015

AbstractGlycosyltransferases (GTs) comprise a prominent family of enzymes that play critical roles in a variety of cellular processes, including cell signaling, cell development, and host–pathogen interactions. Glycosyl transfer can proceed with either inversion or retention of the anomeric configuration with respect to the reaction substrates and products. The elucidation of the catalytic mechanism of retaining GTs remains a major challenge. A native ternary complex of a GT in a productive mode for catalysis is reported, that of the retaining glucosyl‐3‐phosphoglycerate synthase GpgS from M. tuberculosis in the presence of the sugar donor UDP‐Glc, the acceptor substrate phosphoglycerate, and the divalent cation cofactor. Through a combination of structural, chemical, enzymatic, molecular dynamics, and quantum‐mechanics/molecular‐mechanics (QM/MM) calculations, the catalytic mechanism was unraveled, thereby providing a strong experimental support for a front–side substrate‐assisted SNi‐type reaction.
A fuzzy logic‐based variable speed limit controller
Authors: Li Duo , Ranjitkar Prakash 
Published: July 2015

SummaryVariable speed limit (VSL) is an emerging intelligent transportation system (ITS) measure to improve operational and safety performance of motorway systems. Rule‐based algorithms have been widely used in VSL applications because of their comprehensibility and ease of application. However, most of the algorithms proposed in the literature under this category are rather rough for the speed control. Pre‐specified rules show some difficulties in appropriately activating/deactivating control actions in real time because of non‐stationary and nonlinear nature of the traffic system. This paper proposes a fuzzy logic‐based VSL control algorithm as an alternative to the existing VSL control algorithms. The proposed algorithm uses fuzzy sets instead of crisp sets to allow the separation of attribute domains into several overlapping intervals. The discretization using fuzzy sets can help to overcome the sensitivity problem caused by crisp discretization used in the existing VSL algorithms. The proposed algorithm is assessed for a test bed in Auckland using AIMSUN micro‐simulator and verified against a well‐known VSL algorithm. The simulation results show that the proposed algorithm outperforms the existing one to improve the efficiency performance of the motorway system with the critical bottleneck capacity increased by 6.42% and total travel time reduced by 12.39% when compared to a no‐control scenario. Copyright © 2015 John Wiley & Sons, Ltd.
Towards plant protein refinery: Review on protein extraction using alkali and potential enzymatic assistance
Authors: Sari Yessie W. , Mulder Wilhelmus J. , Sanders Johan P. M. , Bruins Marieke E. 
Published: July 2015

AbstractThe globally increasing protein demands require additional resources to those currently available. Furthermore, the optimal usage of protein fractions from both traditional and new protein resources, such as algae and leaves, is essential. Here, we present an overview on alkaline plant protein extraction including the potentials of enzyme addition in the form of proteases and/or carbohydrolases. Strategic biomass selection, combined with the appropriate process conditions can increase protein yields after extraction. Enzyme addition, especially of proteases, can be useful when alkaline protein extraction yields are low. These additions can also be used to enable processing at a pH closer to 7 to avoid the otherwise severe conditions that denature proteins. Finally, a protein biorefinery concept is presented that aims to upcycle residual biomass by separating essential amino acids to be used for food and feed, and non‐essential amino acids for production of bulk chemicals.
In Situ Photocatalytically Heterostructured ZnOAg Nanoparticle Composites as Effective Cathode‐Modifying Layers for Air‐Processed Polymer Solar Cells
Authors: Yuan Kai , Chen Lie , Chen Yiwang 
Published: July 2015

AbstractA heterostructured semiconductor–metal ZnOAg nanoparticle (NP) composite was constructed through a straightforward photocatalytic strategy by using UV irradiation of ZnO NPs and an aqueous solution of Ag precursor. The ZnOAg NP composites serve as an effective cathode‐modifying layer in polymer solar cells (PSCs) with increased short‐circuit current density owing to the light‐trapping effect, and improved optical and electrical conductivity properties compared with pure ZnO NPs. The Ag NPs, which are photodeposited in situ on ZnO NPs, can act as effective antennas for incident light to maximize light harvesting and minimize radiative decay or nonradiative losses, consequently resulting in the enhanced photogeneration of excitons in PSCs. Systematic photoelectron and ‐physical investigations confirm that heterostructured ZnOAg NPs can significantly improve charge separation, transport, and collection, as well as lower charge recombination at the cathode interface, leading to a 14.0 % improvement in air‐processed device power conversion efficiency. In addition, this processable, cost‐effective, and scalable approach is compatible with roll‐to‐roll manufacturing of large‐scale PSCs.
Supramolecular Fluorescent Nanoparticles Constructed via Multiple Non‐Covalent Interactions for the Detection of Hydrogen Peroxide in Cancer Cells
Authors: Wei Xuan , Dong Ruijiao , Wang Dali , Zhao Tianyu , Gao Yongsheng , Duffy Patrick , Zhu Xinyuan , Wang Wenxin 
Published: July 2015

AbstractOverabundance of hydrogen peroxide originating from environmental stress and/or genetic mutation can lead to pathological conditions. Thus, the highly sensitive detection of H2O2 is important. Herein, supramolecular fluorescent nanoparticles self‐assembled from fluorescein isothiocyanate modified β‐cyclodextrin (FITC‐β‐CD)/rhodamine B modified ferrocene (Fc‐RB) amphiphile were prepared through host–guest interaction between FITC‐β‐CD host and Fc‐RB guest for H2O2 detection in cancer cells. The self‐assembled nanoparticles based on a combination of multiple non‐covalent interactions in aqueous medium showed high sensitivity to H2O2 while maintaining stability under physiological condition. Owing to the fluorescence resonance energy transfer (FRET) effect, addition of H2O2 led to obvious fluorescence change of nanoparticles from red (RB) to green (FITC) in fluorescent experiments. In vitro study showed the fluorescent nanoparticles could be efficiently internalized by cancer cells and then disrupted by endogenous H2O2, accompanying with FRET from “on” to “off”. These supramolecular fluorescent nanoparticles constructed via multiple non‐covalent interactions are expected to have potential applications in diagnosis and imaging of diseases caused by oxidative stresses.
Acylation of (Hetero)Arenes through CH Activation with Aroyl Surrogates
Authors: Wu Xiao‐Feng 
Published: July 2015

AbstractIn this Minireview, the major achievements in the acylation of arenes and heteroarenes by CH activation with aroyl groups are summarized and discussed. As the products are carbonyl‐containing compounds that are typical products from carbonylation chemistry, the possible inspirations for these reactions are also discussed, as are mechanistic issues and possible problems for carbonylative diaryl ketone synthesis by CH activation.
A Geomimetic Approach to the Formation and Identification of Fossil Sterane Biomarkers in Crude Oil: 18‐nor‐D‐homo‐Androstane and 5α,14β‐Androstane
Authors: Bender Matthias , Schmidtmann Marc , Summons Roger E. , Rullkötter Jürgen , Christoffers Jens 
Published: July 2015

AbstractA diazonium ion derived from 18‐aminoandrostane rearranged upon decomposition by a carbonium and a carbenium ion to furnish a mixture of a cyclopropanated compound and two D‐homo‐androstenes. Hydrogenation of this mixture gave the saturated hydrocarbons, 18‐nor‐D‐homo‐androstane and 5α,14β‐androstane, which are both fossil sterane biomarkers in Neoproterozoic crude oil. The so far unknown constitution and configuration as well as the geochemical genesis were established by this experiment. The starting material for this investigation, 18‐aminoandrostane, was prepared in twelve steps from androstan‐17‐one (12.5 % overall yield) with a Barton reaction as the key step.
Formation and Reactivity of a Molecular Magnesium Hydride with a Terminal MgH Bond
Authors: Schnitzler Silvia , Spaniol Thomas P. , Maron Laurent , Okuda Jun 
Published: July 2015

AbstractA complex featuring a terminal magnesium hydride bond supported by an NNNN macrocyclic ligand, [Mg{Me3TACD⋅Al(iBu)3}H] (3), was formed from its labile Al(iBu)3 adduct. Use of Al(iBu)3 to block the amido nitrogen of the NNNN macrocyclic ligand was essential to prevent aggregation. The structurally characterized compound 3 reacted with BH3 to give the BH4 derivative, whereas Me3SiCCH and PhSiH3 led to the corresponding acetylide and silyl derivative under H2 elimination. Pyridine is inserted into the MgH bond to give selectively the 1,4‐dihydropyridinate.
High‐throughput RNA sequencing reveals structural differences of orthologous brain‐expressed genes between western lowland gorillas and humans
Authors: Lipovich Leonard , Hou Zhuo‐Cheng , Jia Hui , Sinkler Christopher , McGowen Michael , Sterner Kirstin N. , Weckle Amy , Sugalski Amara B. , Pipes Lenore , Gatti Domenico L. , Mason Christopher E. , Sherwood Chet C. , Hof Patrick R. , Kuzawa Christopher W. , Grossman Lawrence I. , Goodman Morris , Wildman Derek E. 
Published: July 2015

ABSTRACTThe human brain and human cognitive abilities are strikingly different from those of other great apes despite relatively modest genome sequence divergence. However, little is presently known about the interspecies divergence in gene structure and transcription that might contribute to these phenotypic differences. To date, most comparative studies of gene structure in the brain have examined humans, chimpanzees, and macaque monkeys. To add to this body of knowledge, we analyze here the brain transcriptome of the western lowland gorilla (Gorilla gorilla gorilla), an African great ape species that is phylogenetically closely related to humans, but with a brain that is approximately one‐third the size. Manual transcriptome curation from a sample of the planum temporale region of the neocortex revealed 12 protein‐coding genes and one noncoding‐RNA gene with exons in the gorilla unmatched by public transcriptome data from the orthologous human loci. These interspecies gene structure differences accounted for a total of 134 amino acids in proteins found in the gorilla that were absent from protein products of the orthologous human genes. Proteins varying in structure between human and gorilla were involved in immunity and energy metabolism, suggesting their relevance to phenotypic differences. This gorilla neocortical transcriptome comprises an empirical, not homology‐ or prediction‐driven, resource for orthologous gene comparisons between human and gorilla. These findings provide a unique repository of the sequences and structures of thousands of genes transcribed in the gorilla brain, pointing to candidate genes that may contribute to the traits distinguishing humans from other closely related great apes. J. Comp. Neurol. 524:288–308, 2016. © 2015 Wiley Periodicals, Inc.
Optimal Fine‐Scale Structures in Compliance Minimization for a Shear Load
Authors: Kohn Robert V. , Wirth Benedikt 
Published: July 2015

AbstractWe return to a classic problem of structural optimization whose solution requires microstructure. It is well‐known that perimeter penalization assures the existence of an optimal design. We are interested in the regime where the perimeter penalization is weak; i.e., in the effect of perimeter as a selection mechanism in structural optimization. To explore this topic in a simple yet challenging example, we focus on a two‐dimensional elastic shape optimization problem involving the optimal removal of material from a rectangular region loaded in shear. We consider the minimization of a weighted sum of volume, perimeter, and compliance (i.e., the work done by the load), focusing on the behavior as the weight ɛ of the perimeter term tends to 0. Our main result concerns the scaling of the optimal value with respect to ɛ. Our analysis combines an upper bound and a lower bound. The upper bound is proved by finding a near‐optimal structure, which resembles a rank‐2 laminate except that the approximate interfaces are replaced by branching constructions. The lower bound, which shows that no other microstructure can be much better, uses arguments based on the Hashin‐Shtrikman variational principle. The regime being considered here is particularly difficult to explore numerically due to the intrinsic nonconvexity of structural optimization and the spatial complexity of the optimal structures. While perimeter has been considered as a selection mechanism in other problems involving microstructure, the example considered here is novel because optimality seems to require the use of two well‐separated length scales.© 2016 Wiley Periodicals, Inc.
Stability of Regression‐Based Monte Carlo Methods for Solving Nonlinear PDEs
Authors: Alanko Samu 
Published: July 2015

AbstractThe regression‐based Monte Carlo methods for backward stochastic differential equations (BSDEs) have been the object of considerable research, particularly for solving nonlinear partial differential equations (PDEs). Unfortunately, such methods often become unstable when implemented with small time steps because the variance of gradient estimates is inversely proportional to the time step (σ2∼ 1/Δ t). Recently new variance reduction techniques were introduced to address this problem in~a paper by the author and Avellaneda. The purpose of this paper is to provide a rigorous justification for these techniques in the context of the discrete‐time BSDE scheme of Bouchard and Touzi. We also suggest a new higher‐order scheme that makes the variance proportional to the time step (σ2∼Δ t). These techniques are easy to implement. Numerical examples strongly indicate that they render the regression‐based Monte Carlo methods stable for small time steps and thus viable for numerical solution of nonlinear PDEs.© 2016 Wiley Periodicals, Inc.
Platinum(II) Schiff Base Complexes as Photocatalysts for Visible‐Light‐Induced Cross‐Dehydrogenative Coupling Reactions
Authors: Shelar Deepak Prakash , Li Ting‐Ting , Chen Yong , Fu Wen‐Fu 
Published: July 2015

AbstractFour phosphorescent platinum(II) Schiff base complexes are screened for application in visible‐light‐induced cross‐dehydrogenative coupling (CDC) reactions. Preliminary studies show that, among the four platinum(II) complexes, Pt3 is an efficient catalyst for CDC reactions with oxygen as an oxidant. Light irradiation (λ>420 nm) on a mixture of the PtII complex, tertiary amine, and a variety of nucleophiles (nitroalkanes, ketones, or indoles) under aerobic conditions gives α‐functionalized tertiary amines in good to excellent yields. The photoluminescence quenching experiment reveals that the CDC reaction is initiated by photoinduced electron transfer from N‐phenyltetrahydroisoquinoline to the PtII complex. Further, electron spin resonance (ESR) measurements clearly indicate the formation of superoxide radical anions (O2.−) rather than singlet oxygen (1O2) during the photocatalytic reaction.
Improving the Performance of Microbial Fuel Cells through Anode Manipulation
Authors: Lu Min , Qian Yijun , Huang Ling , Xie Xiaoji , Huang Wei 
Published: July 2015

AbstractThe continued focus on microbial fuel cells (MFCs) is due to their applications in power generation and simultaneous wastewater treatment. In the past decade, MFCs have been developed as a new class of energy devices and hold promise for broad applications in bioremediation, bioproduction, and biosensing. Despite the advances, the overall performance of MFCs is still limited, and particularly the energy loss at anode, where electrons are generated, is a restriction. Recent progress on MFC anodes has led to several effective approaches to improve MFC performance. In this Minireview, we discuss the performance losses in MFC anodes from the electrochemical point of view and then focus on the main strategies developed to overcome the anode performance losses. We also discuss the potential directions of future research on MFC anodes.
An improved genetic algorithm and its applications to the optimisation design of an aspirated compressor profile
Authors: Jinhuan Zhang , Zhenggui Zhou 
Published: July 2015

SummaryGenetic algorithm (GA) is a widely used method for numerical optimisation owing to their good global search ability; however, their local search ability has an obvious shortcoming. To improve local search ability, this paper introduces a simplex method and combines it with a GA to form an improved genetic algorithm (IGA). In the IGA, at each generation of the original GA, high‐fitness individuals are selected as vertices of a simplex, and then a one‐dimensional search within the simplex is conducted to obtain the most‐fit individuals while replacing the inferior ones. Typical test functions show that the IGA can effectively improve the optimisation effect over that of the original GA. To further verify the IGA's practicability, an aspirated compressor profile is optimised with profile, suction flow rate and suction flow location as coupled design parameters. The results again show that the IGA has a better optimising effect than the GA. In addition, it is also verified that coupling the profile and suction flow parameters results in a design that outperforms the uncoupled design; therefore, designing an aspirated compressor blade by arranging suction flow on a conventional blade without considering suction flow is not a good method. Copyright © 2015 John Wiley & Sons, Ltd.
The organization of the posterior parietal cortex devoted to upper limb actions: An fMRI study
Authors: Ferri Stefania , Rizzolatti Giacomo , Orban Guy A. 
Published: July 2015

AbstractThe present fMRI study examined whether upper‐limb action classes differing in their motor goal are encoded by different PPC sectors. Action observation was used as a proxy for action execution. Subjects viewed actors performing object‐related (e.g., grasping), skin‐displacing (e.g., rubbing the skin), and interpersonal upper limb actions (e.g., pushing someone). Observation of the three action classes activated a three‐level network including occipito‐temporal, parietal, and premotor cortex. The parietal region common to observing all three action classes was located dorsally to the left intraparietal sulcus (DIPSM/DIPSA border). Regions specific for observing an action class were obtained by combining the interaction between observing action classes and stimulus types with exclusive masking for observing the other classes, while for regions considered preferentially active for a class the interaction was exclusively masked with the regions common to all observed actions. Left putative human anterior intraparietal was specific for observing manipulative actions, and left parietal operculum including putative human SII region, specific for observing skin‐displacing actions. Control experiments demonstrated that this latter activation depended on seeing the skin being moved and not simply on seeing touch. Psychophysiological interactions showed that the two specific parietal regions had similar connectivities. Finally, observing interpersonal actions preferentially activated a dorsal sector of left DIPSA, possibly the homologue of ventral intraparietal coding the impingement of the target person's body into the peripersonal space of the actor. These results support the importance of segregation according to the action class as principle of posterior parietal cortex organization for action observation and by implication for action execution. Hum Brain Mapp 36:3845–3866, 2015. © 2015 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.
Ecohydrological separation in wet, low energy northern environments? A preliminary assessment using different soil water extraction techniques
Authors: Geris Josie , Tetzlaff Doerthe , McDonnell Jeffrey , Anderson James , Paton Graeme , Soulsby Chris 
Published: July 2015

AbstractEcohydrological studies in seasonally dry climatic regions have revealed isotopic separation of the sources of water used by trees and those that generate stream flow, also referred to as the ‘two water worlds’ hypothesis. Here we investigated whether similar separation occurs in a wet, low energy northern (Latitude 57°) environment in Scotland. For two common soil types (Histosols and Podzols) at three soil depths, and at both forested (with Scots Pine (Pinus sylvestris)) and non‐forested sites, we compared the stable isotope composition of soil water held at increasing soil water tensions. These were assessed by different soil water extraction techniques: Rhizon samplers (mobile water), centrifugation at different speeds (representing different tensions), and cryogenic extraction (bulk water). Sampling occurred during a relatively dry summer. Water that was held at increasing tensions appeared more depleted than more mobile water, consistent with older (winter) precipitation. This pattern was independent of soil type, vegetation cover, and time during the growing season, although there was a slight tendency towards less separation with soil depth. Nevertheless, soil waters in this generally wet, low energy environment exhibited only minor evaporative enrichment, limited to the upper soil profile only. Furthermore, stream water showed no deviation from the local meteoric water line. Preliminary sampling for tree xylem water suggested uptake of evaporated soil water from the near surface soil horizons (upper 10 cm) where fine root densities are concentrated. For Histosols in particular, tree water appeared lagged in its isotopic composition compared to the soil water time series. Although more work is needed to fully test the ‘two water worlds’ hypothesis, our initial analyses did not provide clear evidence to support this in wet, low energy northern environments. Copyright © 2015 John Wiley & Sons, Ltd.