bluuebunny/crossref_metadata_2025_split huggingface dataset:
Advanced Porous Materials in Mixed Matrix Membranes
Authors: Cheng Youdong , Ying Yunpan , Japip Susilo , Jiang Shu‐Dong , Chung Tai‐Shung , Zhang Sui , Zhao Dan 
Published: July 2018

AbstractMembrane technology has gained great interest in industrial separation processing over the past few decades owing to its high energy efficiency, small capital investment, environmentally benign characteristics, and the continuous operation process. Among various types of membranes, mixed matrix membranes (MMMs) combining the merits of the polymer matrix and inorganic/organic fillers have been extensively investigated. With the rapid development of chemistry and materials science, recent studies have shifted toward the design and application of advanced porous materials as promising fillers to boost the separation performance of MMMs. Here, first a comprehensive overview is provided on the choices of advanced porous materials recently adopted in MMMs, including metal–organic frameworks, porous organic frameworks, and porous molecular compounds. Novel trends in MMMs induced by these advanced porous fillers are discussed in detail, followed by a summary of applying these MMMs for gas and liquid separations. Finally, a concise conclusion and current challenges toward the industrial implementation of MMMs are outlined, hoping to provide guidance for the design of high‐performance membranes to meet the urgent needs of clean energy and environmental sustainability.
Benzoxadiazole and Benzoselenadiazole as π‐Bridges in Nonfullerene Acceptors for Efficient Polymer Solar Cells
Authors: Nian Yaowen , Pan Feilong , Li Suhan , Jiang Haiying , Feng Shizhen , Zhang Lianjie , Cao Yong , Chen Junwu 
Published: July 2018

AbstractFused‐ring electron acceptors with acceptor‐donor‐acceptor (A‐D‐A) structure have become a hot research field in recent years. In this work, 2,1,3‐benzoxadiazole (BO) and 2,1,3‐benzoselenadiazole (BS) were introduced as π‐bridges between indaceno [1,2‐b : 5,6‐b′] dithiophene (IDT) cores and rhodanine termini for two nonfullerene acceptors IDTBOR and IDTBSR, to compare the structure‐property relationship. Inserting BO as the π‐bridge afforded IDTBOR with deeper LUMO and HOMO levels, whereas BS‐based IDTBSR possessed a smaller optical band gap. With PBDB‐T as polymer donor, IDTBOR‐ and IDTBSR‐based solar cells showed power conversion efficiencies of 7.74 and 6.95%, respectively. A higher open‐circuit voltage of 0.95 V was found for IDTBSR, owing to its up‐lying LUMO level. A higher short‐circuit current density of 15.98 mA/cm2 and fill factor of 54.67% were achieved for IDTBOR, mainly because of the higher electron mobility and better structure order in the blend film. The results suggest that BO and BS units are valuable π‐bridges to construct efficient nonfullerene acceptors.
Chemical Design of Non‐Ionic Polymer Brushes as Biointerfaces: Poly(2‐oxazine)s Outperform Both Poly(2‐oxazoline)s and PEG
Authors: Morgese Giulia , Verbraeken Bart , Ramakrishna Shivaprakash N. , Gombert Yvonne , Cavalli Emma , Rosenboom Jan‐Georg , Zenobi‐Wong Marcy , Spencer Nicholas D. , Hoogenboom Richard , Benetti Edmondo M. 
Published: July 2018

AbstractThe era of poly(ethylene glycol) (PEG) brushes as a universal panacea for preventing non‐specific protein adsorption and providing lubrication to surfaces is coming to an end. In the functionalization of medical devices and implants, in addition to preventing non‐specific protein adsorption and cell adhesion, polymer‐brush formulations are often required to generate highly lubricious films. Poly(2‐alkyl‐2‐oxazoline) (PAOXA) brushes meet these requirements, and depending on their side‐group composition, they can form films that match, and in some cases surpass, the bioinert and lubricious properties of PEG analogues. Poly(2‐methyl‐2‐oxazine) (PMOZI) provides an additional enhancement of brush hydration and main‐chain flexibility, leading to complete bioinertness and a further reduction in friction. These data redefine the combination of structural parameters necessary to design polymer‐brush‐based biointerfaces, identifying a novel, superior polymer formulation.
Stimulus‐induzierte Anion‐Kation‐Exciplexbildung in Kupfer(I)‐Komplexen als Mechanismus für mechanochrome Phosphoreszenz
Authors: Hupp Benjamin , Nitsch Jörn , Schmitt Tanja , Bertermann Rüdiger , Edkins Katharina , Hirsch Florian , Fischer Ingo , Auth Michael , Sperlich Andreas , Steffen Andreas 
Published: July 2018

AbstractDie mechanistische Untersuchung von mechanochromer Lumineszenz ist sehr wichtig zur Entwicklung von Materialien für die Sensorik, Datenspeicherung oder Lumineszenzschalter. Die strukturelle Ursache in phosphoreszierenden Systemen ist selten bekannt und somit die Aufstellung von Struktur‐Eigenschafts‐Beziehungen eine große Herausforderung. Für d10‐Münzmetallkomplexe wurden Änderungen der M‐M‐Wechselwirkungen als Hauptmechanismus vorgeschlagen. Wir zeigen mit einer mechanisch induzierten, reversiblen Kation‐Anion‐Exciplexbildung, basierend auf Cu‐F‐Interaktionen, einen neuen Mechanismus, der zu sehr effizienter mechanochromer Phosphoreszenz mit für CuI‐Komplexe ungewöhnlich weiten Emissionsverschiebung von UV‐blau zu gelb führt. Die gelbe Lumineszenz ist thermo‐ und vaporesponsiv, wodurch sowohl Weißlicht als auch die ursprüngliche UV‐blaue Emission generiert werden können.
Chemodynamic Therapy: Tumour Microenvironment‐Mediated Fenton and Fenton‐like Reactions
Authors: Tang Zhongmin , Liu Yanyan , He Mingyuan , Bu Wenbo 
Published: July 2018

AbstractTailored to the specific tumour microenvironment, which involves acidity and the overproduction of hydrogen peroxide, advanced nanotechnology has been introduced to generate the hydroxyl radical (.OH) primarily for tumour chemodynamic therapy (CDT) through the Fenton and Fenton‐like reactions. Numerous studies have investigated the enhancement of CDT efficiency, primarily the increase in the amount of .OH generated. Notably, various strategies based on the Fenton reaction have been employed to enhance .OH generation, including nanomaterials selection, modulation of the reaction environment, and external energy fields stimulation, which are discussed systematically in this Minireview. Furthermore, the potential challenges and the methods used to facilitate CDT effectiveness are also presented to support this cutting‐edge research area.
Recent updates of fluoroquinolones as antibacterial agents
Authors: Ezelarab Hend A. A. , Abbas Samar H. , Hassan Heba A. , Abuo‐Rahma Gamal El‐Din A. 
Published: July 2018

AbstractFluoroquinolones remain one of the most important kind of antibacterial agents used nowadays. The emergence of more virulent and resistant strains of bacteria by the development of either mutated DNA‐binding proteins or efflux pump mechanism for drugs is considered the main problem associated with the therapeutic use of these drugs. This situation participated in pushing researchers to design new fluoroquinolone derivatives, mainly with different substituents at C‐7 to withstand these resistant strains of bacteria and to obtain a wider spectrum of activity including activity against anaerobic organisms. Conjugation of fluoroquinolones with substitutions such as 1,2,4‐triazoles, alkyl oximes, flavonoids, aryl furans, benzofuroxans, metronidazoles or even other antibiotics such as neomycin‐B produced derivatives that have a superior and wider spectrum of activity and better resistance than the classical fluoroquinolone agents. Addition of a hydroxamic acid moiety to fluoroquinolones also increased the activity against Proteus mirabilis, which represents one of the most resistant strains of bacteria in urinary tract infections. This review aims to highlight the recent updates made for fluoroquinolones for broadening the spectrum of activity to become active not only against resistant strains of bacteria but also against anaerobic pathogens.
Social capital and firms' environmental innovations: The moderating role of environmental scanning
Authors: Liao Zhongju 
Published: July 2018

AbstractSeen as an effective way to balance financial and environmental goals, environmental innovation has become a priority for firms. Based on the theory of social capital, this study examined the antecedents of firms' environmental innovations. Selecting environmental scanning as the moderator, this study analyzed the relationship between the three dimensions of social capital and environmental innovation. Two hundred and forty firms in the manufacturing industry were selected as the sample, and the data were analyzed using SPSS 21.0. The results showed that structural and relational capital had a positive effect on environmental innovation, while the impact of cognitive capital was not significant. Environmental scanning played the role of a positive moderator in the relationships between structural capital, relational capital and environmental innovation. Finally, in accordance with the conclusions, this study proposes related managerial implications and points out future research directions.
Towards Encapsulation of Nanoparticles in Chabazite Through Interzeolite Transformation
Authors: Rasmussen Kristoffer Hauberg , Mielby Jerrik , Kegnæs Søren 
Published: July 2018

AbstractEncapsulation of Pt nanoparticles (1–2 nm) in the small pore zeolite chabazite (CHA) was achieved by a seed‐ and structure‐directing agent‐free interzeolite transformation from zeolite Y (FAU). Prior to the transformation, the Pt nanoparticles were encapsulated in the commercially available large pore zeolite H−Y by simple incipient wetness impregnation. The H−Y was then converted into CHA in a solution of KOH under hydrothermal conditions at 95 °C. All catalysts were characterized by XRD, N2‐physisorption, H2‐chemisorption, TEM and XPS and their catalytic activity were tested in CO oxidation. Although the catalytic activity of the encapsulated Pt nanoparticles decreased over time, it still remained more active than a reference catalyst prepared by impregnation. The thermal stability of the catalysts was investigated after calcination at 400 °C for 18 hours. Compared to the other catalysts, the encapsulated Pt nanoparticles only resulted in a small decrease in catalytic activity.
Self‐Assembly of Chiral‐at‐End Diketopyrrolopyrroles: Symmetry Dependent Solution and Film Optical Activity and Photovoltaic Performance
Authors: Hume Paul A. , Monks James P. , Pop Flavia , Davies E. Stephen , MacKenzie Roderick C. I. , Amabilino David B. 
Published: July 2018

AbstractChiral thiophene‐diketopyrrolopyrrole derivatives have been synthesised to investigate the potential of stereochemistry and symmetry as a means of modulating properties by influencing self‐assembly of these purely organic materials. In particular, derivatives of diketopyrrolopyrrole were employed because of their proven interest as dyes, especially for organic solar cells. The natural product myrtenal was used as the source of stereochemistry, introduced through a Kröhnke reaction of a thiophene‐bearing pyridinium salt and diketopyrrolopyrroles were prepared through Suzuki coupling with this chiral moiety at one end only as well as at both ends. Absorption spectroscopy and electrochemistry confirmed the potential suitability of the compounds for photovoltaic devices. The nanostructures formed by the compounds have been probed with circular dichroism spectroscopy in solution and in films. It is shown that a chiral C2 symmetric molecule assembles in solution giving a strong circular dichroic signal while as a film this optical activity is nulled, whereas an asymmetric homologue is most optically active as a thin film. The X‐ray crystal structure of the asymmetric compound shows a polar order of the molecules that might explain this observation. The lack of optical activity in solution is very likely a result of the high solubility of the compound. The results reaffirm the sensitivity of circular dichroism spectroscopy to inter‐chromophore organisation, whereas absorption spectroscopy in the visible region reveals only slight changes to the bands. The differing order in the compounds also affects their performance in bulk heterojunction photovoltaic devices. Atomic force microscopy of the blended thin films with the fullerene derivative usually employed (PC61BM) showed that smooth and well mixed films were achieved, with the conditions required during spin coating depending greatly on the derivative, because of their differing solubility. The apparently better performance of the symmetrical compound (although with very low efficiency) is probably a result of the alignment of the molecules inferred by the circular dichroism experiments, whereas the asymmetric compound presumably adopts a twisted supramolecular organisation.
A New Protocol to Generate Catalytically Active Species of Group 4–6 Metals by Organosilicon‐Based Salt‐Free Reductants
Authors: Tsurugi Hayato , Mashima Kazushi 
Published: July 2018

AbstractHerein, we provide a new protocol to reduce various transition‐metal complexes by using organosilicon compounds in a salt‐free fashion with the great advantage of generating pure low‐valent metal species and metallic(0) nanoparticles, in sharp contrast to reductant‐derived salt contaminants obtained by reduction with metal reductants. The organosilicon derivatives 1,4‐bis(trimethylsilyl)‐2,5‐cyclohexadiene (1 a), 1‐methyl‐3,6‐bis(trimethylsilyl)‐1,4‐cyclohexadiene (1 b), 1,4‐bis(trimethylsilyl)‐1,4‐diaza‐2,5‐cyclohexadiene (2 a), 2,5‐dimethyl‐1,4‐bis(trimethylsilyl)‐1,4‐diaza‐2,5‐cyclohexadiene (2 b), 2,3,5,6‐tetramethyl‐1,4‐bis(trimethylsilyl)‐1,4‐diaza‐2,5‐cyclohexadiene (2 c), and 1,1′‐bis(trimethylsilyl)‐1H,1′H‐4,4′‐bipyridinylidene (3) all served as versatile reductants for early transition‐metal complexes and produced only easy‐to‐remove organic compounds, such as trimethylsilylated compounds and the corresponding aromatics, for example, benzene, toluene, pyrazine, and 4,4′‐bipyridyl, as the byproducts. The high solubility of the reductants in organic solvents enabled us to monitor the catalytic reactions directly and to detect any catalytically active species so that we could elucidate the reaction mechanism.
Directed Evolution of a Bond‐Forming Enzyme: Ultrahigh‐Throughput Screening of Microbial Transglutaminase Using Yeast Surface Display
Authors: Deweid Lukas , Neureiter Lara , Englert Simon , Schneider Hendrik , Deweid Jakob , Yanakieva Desislava , Sturm Janna , Bitsch Sebastian , Christmann Andreas , Avrutina Olga , Fuchsbauer Hans‐Lothar , Kolmar Harald 
Published: July 2018

AbstractMicrobial transglutaminase from Streptomyces mobaraensis (mTG) has emerged as a useful biotechnological tool due to its ability to crosslink a side chain of glutamine and primary amines. To date, the substrate specificity of mTG is not fully understood, which poses an obvious challenge when mTG is used to address novel targets. To that end, a viable strategy providing an access to tailor‐made transglutaminases is required. This work reports an ultrahigh‐throughput screening approach based on yeast surface display and fluorescence‐activated cell sorting (FACS) that enabled the evolution of microbial transglutaminase towards enhanced activity. Five rounds of FACS screening followed by recombinant expression of the most potent variants in E. coli yielded variants that possessed, compared to the wild type enzyme, improved enzymatic performance and labeling behavior upon conjugation with an engineered therapeutic anti‐HER2 antibody. This robust and generally applicable platform enables tailoring of the catalytic efficiency of mTG.
Singlet O2 Oxidation of a Deprotonated Guanine‐Cytosine Base Pair and Its Entangling with Intra‐Base‐Pair Proton Transfer
Authors: Lu Wenchao , Sun Yan , Tsai Midas , Zhou Wenjing , Liu Jianbo 
Published: July 2018

AbstractWe report an experimental and computational study on the 1O2 oxidation of gas‐phase deprotonated guanine‐cytosine base pair [G ⋅ C−H]− that is composed of 9HG ⋅ [C−H]− and 7HG ⋅ [C−H]− (pairing 9H‐ or 7H‐guanine with N1‐deprotonated cytosine), and 9HG ⋅ [C−H]−_PT and 7HG ⋅ [C−H]−_PT (formed by intra‐base‐pair proton transfer from the N1 of guanine to the N3 of [C−H]−). The conformer‐averaged reaction product ions and cross section were measured over a center‐of‐mass collision energy range from 0.1 to 0.5 eV using a guided‐ion‐beam tandem mass spectrometer. To explore conformation‐specific reactivity, collision dynamics of 1O2 with each of the four [G ⋅ C−H]− conformers was simulated at B3LYP/6‐31G(d). Trajectories showed that the 1O2 oxidation of the base pair entangles with intra‐base‐pair proton transfer, and prefers to occur in a collision when the base pair adopts a proton‐transferred structure; trajectories also indicate that the 9HG‐containing base pair favors stepwise formation of 4,8‐endoperoxide of guanine, whereas the 7HG‐containing base pair prefers concerted formation of guanine 5,8‐endoperoxide. Using trajectory results as a guide, potential energy surfaces (PESs) along all possible reaction pathways were established using the approximately spin‐projected ωB97XD/6‐311++G(d,p)//B3LYP/6‐311++G(d,p) method. PESs have not only rationalized trajectory findings but provided more accurate energetics and indicated that the proton‐transferred base‐pair conformers have lower activation barriers for oxidation than their non‐proton‐transferred counterparts.
The effects of intraday news flow on dealers' quotations, market liquidity, and volatility
Authors: Karam Arzé 
Published: July 2018

AbstractMarket regulators emphasize that the reduction in dealers' liquidity to today's markets is one of the drivers of extreme behaviour such as flash crash. Yet the challenge is to understand the effects of intraday news flow on dealers' quoting behaviour, high‐frequency returns, price volatility, liquidity, and trading activity. This paper addresses these issues shortly before the analyst recommendation changes on the Nasdaq. The sample period is 2004 at times where dealers were frequently displaying their quotations on the system. Results show that dealers remain active in quoting, in particular, in the events when the report is issued by their affiliated analysts. Their activity is associated with lower inside spreads, more trading, a more two‐sided market, and lower order imbalance.
Detection of copy number variants using chromosomal microarray analysis for the prenatal diagnosis of congenital heart defects with normal karyotype
Authors: Song Tingting , Wan Shanning , Li Yu , Xu Ying , Dang Yinghui , Zheng Yunyun , Li Chunyan , Zheng Jiao , Chen Biliang , Zhang Jianfang 
Published: July 2018

BackgroundWith the increasing availability of chromosomal microarray analysis (CMA) for congenital heart defect (CHD), genetic testing now faces new challenges due to results with uncertain clinical impact. Studies are needed to better define the penetrance of genetic variants. The aim of the study was to examine the association between CMA and CHDs in fetuses with normal karyotype.MethodsThis was a retrospective study of 190 fetuses with normal karyotype that underwent CMA after a diagnosis of CHD by fetal ultrasound. Invasive prenatal diagnosis was performed between January 2015 and December 2016 at the first affiliated hospital of Air Force Medical University.ResultsChromosomal microarray analysis detected pathogenic copy number variants (pCNVs) in 13/190 (6.84%) fetuses, likely pCNVs in 5/190 (2.63%), and variants of unknown significance (VOUS) in 14/190 (7.37%). Among those with pCNVs, none (0%) yielded a normal live birth. Among those with likely pCNVs, 2/5 (40.0%) yielded a live birth. Among the fetuses with VOUS, 10/14 (71.5%) yielded a live birth.ConclusionThese results highlight the usefulness of CMA for prenatal genetic diagnosis of fetuses with CHDs and normal karyotype. In fetuses with CHD, the application of CMA could increase the detection rate of pCNVs causing CHDs. In this study, some VOUS were likely pathogenic, but additional studies are necessary to confirm these findings.
Core Job Characteristic and Uncertainty Avoidance: Into the Black Box of Transformational Leadership Effect on Creativity
Authors: Wang Peng 
Published: July 2018

AbstractDrawing upon the job characteristic model and the “management of meaning” perspective, this study examines the process and conditions through which transformational leadership fosters employee creativity. Our results reveal that the effect of transformational leadership on creativity is mediated by employees’ perceptions of core job characteristics (variety, identity, significance, autonomy, feedback). This mediation effect is further moderated by employees’ uncertainty avoidance orientation. Specifically, transformational leaders foster creativity through followers’ perceptions of core job characteristics only among employees low on uncertainty avoidance. The association between enhanced job characteristics and creativity is more positive for employees with low uncertainty avoidance orientation than those with high uncertainty avoidance orientation. Implications and future research directions are discussed.
A guano‐derived δ13C and δ15N record of climate since the Medieval Warm Period in north‐west Romania
Authors: Cleary Daniel M. , Onac Bogdan P. , Tanţău Ioan , Forray Ferenc L. , Wynn Jonathan G. , Ionita Monica , Tămaş Tudor 
Published: July 2018

ABSTRACTA 285‐cm core of bat guano was recovered from Măgurici Cave in north‐west Romania and analyzed for δ13C, δ15N and pollen. Guano deposition occurred from AD 881 until 1240 and from AD 1651 to 2013, allowing for the interpretation of summer variations in precipitation and temperature during the Medieval Warm Period (MWP) and the Little Ice Age (LIA). A 2‰ increase in δ13C, 1.5‰ decrease in δ15N, and the presence of Ulmus, Quercus and Carpinus betulus indicate a warm and dry MWP occurred in the region. The lack of deposition during the beginning of the LIA suggests a possible climate‐induced change in prey availability resulting in bats vacating the cave. Variation of δ13C values between −25 and −23‰ at AD 1650 (LIA) indicates similar drier conditions as at the end of MWP. However, a 2‰ decrease in δ13C values that occurred between AD 1790 and 1900 suggests climate was trending towards wetter conditions at the end of the LIA. From AD 1938 to 2013, δ13C values appear to be more influenced by temperature, indicating that this parameter had a more significant effect on carbon discrimination than water availability.
Southern Hemisphere westerly wind influence on southern New Zealand hydrology during the Lateglacial and Holocene
Authors: Anderson Harris J. , Moy Christopher M. , Vandergoes Marcus J. , Nichols Jonathan E. , Riesselman Christina R. , Van Hale Robert 
Published: July 2018

ABSTRACTThe strength and latitudinal position of the southern westerly winds (SWW) influence mid‐latitude precipitation and carbon cycling in the Southern Ocean. Despite the important role the westerlies play in the global climate system, past variability is poorly constrained. Here, we present a geochemical record of hydroclimate change from Lake Von in south‐west New Zealand that spans the last 16 000 years. During the Lateglacial and early Holocene, we find stratigraphic and geochemical evidence for three distinct periods of low lake levels that occur during North Atlantic cold events when the Intertropical Convergence Zone is displaced southwards, Southern Ocean upwelling is enhanced and the Antarctic is rapidly warming. We attribute these hydrological changes to southward shifts of the SWW and associated storm tracks that cause arid conditions in southern New Zealand. During the early Holocene, we find evidence for an extended period of low lake levels that are caused by a combination of diminished wind strength, higher air temperatures and reduced seasonality. Finally, we interpret an overall intensification of the SWW after 5500 cal a bp. Our results support the idea that climate mechanisms originating in the high latitudes and the tropics work together to influence the SWW on millennial timescales.