bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Visible‐Light‐Driven Iminyl Radical‐Mediated C−C Single Bond Cleavage/Radical Addition Cascade of Oxime Esters
Authors: Yu Xiao‐Ye , Chen Jia‐Rong , Wang Peng‐Zi , Yang Meng‐Nan , Liang Dong , Xiao Wen‐Jing 
Published: December 2017

AbstractA room‐temperature, visible‐light‐driven N‐centered iminyl radical‐mediated and redox‐neutral C−C single bond cleavage/radical addition cascade reaction of oxime esters and unsaturated systems has been accomplished. The strategy tolerates a wide range of O‐acyl oximes and unsaturated systems, such as alkenes, silyl enol ethers, alkynes, and isonitrile, enabling highly selective formation of various chemical bonds. This method thus provides an efficient approach to various diversely substituted cyano‐containing alkenes, ketones, carbocycles, and heterocycles.
Boosting Electrochemical Water Oxidation with Metal Hydroxide Carbonate Templated Prussian Blue Analogues
Authors: Indra Arindam , Paik Ungyu , Song Taeseup 
Published: December 2017

AbstractThe development of efficient and stable catalyst systems with low‐cost, abundant, and non‐toxic materials is the primary demand for electrochemical water oxidation. A unique method is reported for the syntheses of metal hydroxide carbonate templated Prussian blue analogues (PBAs) on carbon cloth and their outstanding water oxidation activities in alkaline medium. The best water oxidation activity is obtained with cobalt hydroxide carbonate templated t‐CoII‐CoIII with an overpotential as low as 240 mV to reach a current density of 10 mA cm−2. It produces constant current over 50 h in chronoamperometric measurements. Moreover, the catalysts outperform the activities of the PBAs prepared without any template and even the noble metal catalyst RuO2. Spectroscopic and microscopic studies show that the PBAs are transformed into layered hydroxide–oxyhydroxide structures during electrochemical process and provide the active sites for the water oxidation.
Deuterated Molecular Ruby with Record Luminescence Quantum Yield
Authors: Wang Cui , Otto Sven , Dorn Matthias , Kreidt Elisabeth , Lebon Jakob , Sršan Laura , Di Martino‐Fumo Patrick , Gerhards Markus , Resch‐Genger Ute , Seitz Michael , Heinze Katja 
Published: December 2017

AbstractThe recently reported luminescent chromium(III) complex 13+ ([Cr(ddpd)2]3+; ddpd=N,N′‐dimethyl‐N,N′‐dipyridine‐2‐yl‐pyridine‐2,6‐diamine) shows exceptionally strong near‐IR emission at 775 nm in water under ambient conditions (Φ=11 %) with a microsecond lifetime as the ligand design in 13+ effectively eliminates non‐radiative decay pathways, such as photosubstitution, back‐intersystem crossing, and trigonal twists. In the absence of energy acceptors, such as dioxygen, the remaining decay pathways are energy transfer to high energy solvent and ligand oscillators, namely OH and CH stretching vibrations. Selective deuteration of the solvents and the ddpd ligands probes the efficiency of these oscillators in the excited state deactivation. Addressing these energy‐transfer pathways in the first and second coordination sphere furnishes a record 30 % quantum yield and a 2.3 millisecond lifetime for a metal complex with an earth‐abundant metal ion in solution at room temperature.
Incorporation of 2,6‐Connected Azulene Units into the Backbone of Conjugated Polymers: Towards High‐Performance Organic Optoelectronic Materials
Authors: Xin Hanshen , Ge Congwu , Jiao Xuechen , Yang Xiaodi , Rundel Kira , McNeill Christopher R. , Gao Xike 
Published: December 2017

AbstractAzulene is a promising candidate for constructing optoelectronic materials. An effective strategy is presented to obtain high‐performance conjugated polymers by incorporating 2,6‐connected azulene units into the polymeric backbone, and two conjugated copolymers P(TBAzDI‐TPD) and P(TBAzDI‐TFB) were designed and synthesized based on this strategy. They are the first two examples for 2,6‐connected azulene‐based conjugated polymers and exhibit unipolar n‐type transistor performance with an electron mobility of up to 0.42 cm2 V−1 s−1, which is among the highest values for n‐type polymeric semiconductors in bottom‐gate top‐contact organic field‐effect transistors. Preliminary all‐polymer solar cell devices with P(TBAzDI‐TPD) as the electron acceptor and PTB7‐Th as the electron donor display a power conversion efficiency of 1.82 %.
Stocking impact, population structure and conservation of wild brown trout populations in inner Galicia (NW Spain), an unstable hydrologic region
Authors: Vera Manuel , Martinez Paulino , Bouza Carmen 
Published: December 2017

Abstract1. Brown trout (Salmo trutta) is an important conservation resource in the Iberian Peninsula. The Atlantic is considered the most hydrologically stable region for the species, although inner Galicia (NW Spain) shows Mediterranean (unstable) climatic conditions. The Galician region, threatened by past releases of brown trout individuals from central European origin, harbours two native lineages, one of them endemic to the Iberian Peninsula. These populations are thus highly valuable for conservation, as well as being important for recreational fisheries.2. In total, 546 individuals from 16 sampling sites (15 natural locations from inner Galicia and one from a central European hatchery stock) were genotyped for 11 nuclear markers (10 microsatellite loci and the LDH‐C* locus) to analyse genetic variability, population structure and introgression impact from stocking in order to assess the conservation status of brown trout in the region. Moreover, correlation among hatchery introgression and environmental variables relevant for species population dynamics was also investigated.3. Genetic variability was within the range of Iberian brown trout (He = 0.500–0.600). Stocking impact was higher than previously reported values for the Atlantic region and was related to environmental instability. Highly significant native population differentiation was observed in the whole region (FST = 0.283), at least four main genetic groups being detected across the geographic distribution studied.4. Conservation strategies at local level (including the creation of genetic refuges and temporal monitoring of genetic composition) are suggested to agencies and administrations for the sustainable management of brown trout.
Adding practical experience to computer security course
Authors: Stanisavljevic Zarko , Vuletic Pavle 
Published: December 2017

AbstractComputer security has become one of the core areas according to IEEE Computer Society and ACM Joint Task Force curriculum guidelines for undergraduate degree programs in computer engineering and software engineering. At the University of Belgrade, School of Electrical Engineering there is a course called Computer Security that is taught to software engineering and computer engineering students for the past 9 years. During this time a significant change was made to the course regarding the level of practical students’ work. Several factors initiated the change: the recommendations in the curriculum guidelines, the analysis of the students’ success at the exams, and the students’ opinion. The impact of gradual transition from no practical activities at all to laboratory exercises and practical project at the course are described in this paper. Results show that the introduction of laboratory exercises at the course helped students to better understand some of the core areas and that the introduction of practical project increased their overall knowledge in the computer security area.
Strictly Conserved Residues in Euphorbia tirucalli β‐Amyrin Cyclase: Trp612 Stabilizes Transient Cation through Cation–π Interaction and CH–π Interaction of Tyr736 with Leu734 Confers Robust Local Protein Architecture
Authors: Aiba Yukari , Watanabe Takumi , Terasawa Yuri , Nakano Chiaki , Hoshino Tsutomu 
Published: December 2017

AbstractThe functions of Trp612, Leu734, and Tyr736 of Euphorbia tirucalli β‐amyrin synthase were examined. The aliphatic variants (Ala, Val, Met) of Trp612 showed almost no activity, but the aromatic variants exhibited high activities: 12.5 % of the wild‐type activity for the W612H variant, 43 % for W612F, and 63 % for W612Y. That is, the enzymatic activities of the variants increased in proportion to the increase in π‐electron density. Thus, the major function of Trp612 is to stabilize transient cations through a cation–π interaction. The Phe and Tyr variants caused a distorted folding conformation, especially at the E‐ring site, which generated the aberrantly cyclized products germanicol and lupeol. The L734G and L734A variants exhibited significantly decreased activities but yielded taraxerol in a high production ratio. The Val, Ile, and Met variants showed markedly high activities (56–78 % of wild‐type activity); therefore, appropriate steric bulk is required at this position. The aliphatic variants of Tyr736 showed markedly decreased activities, but the Phe mutant exhibited high activity (67 %), which indicates that the π electrons are critical for catalysis. Homology modeling indicated that Tyr736 and Leu734 are perpendicular to the substrate and are situated face to face, which suggests that a CH–π interaction occurs between Tyr736 and Leu734, reinforcing the protein architecture, and that Tyr736 cannot stabilize cationic intermediates through a cation–π interaction.
A Single Mutation Increases the Activity and Stability of Pectobacterium carotovorum Nitrile Reductase
Authors: Zhou Zheng , Li Min , Xu Jian‐He , Zhang Zhi‐Jun 
Published: December 2017

AbstractNitrile reductases are considered to be promising and environmentally benign nitrile‐reducing biocatalysts to replace traditional metal catalysts. Unfortunately, the catalytic efficiencies of the nitrile reductases reported so far are very low. To date, all attempts to increase the catalytic activity of nitrile reductases by protein engineering have failed. In this work, we successfully increased the specific activity of a nitrile reductase from Pectobacterium carotovorum from 354 to 526 U gprot−1 by engineering the substrate binding pocket; moreover, the thermostability was also improved (≈2‐fold), showing half‐lives of 140 and 32 h at 30 and 40 °C, respectively. In the bioreduction of 2‐amino‐5‐cyanopyrrolo[2,3‐d]pyrimidin‐4‐one (preQ0) to 2‐amino‐5‐aminomethylpyrrolo[2,3‐d]pyrimidin‐4‐one (preQ1), the variant was advantageous over the wild‐type enzyme with a higher reaction rate and complete conversion of the substrate within a shorter period. Homology modeling and docking analysis revealed some possible origins of the increased activity and stability. These results establish a solid basis for future engineering of nitrile reductases to increase the catalytic efficiency further, which is a prerequisite for applying these novel biocatalysts in synthetic chemistry.
Silica‐Supported Molecular Catalysts for Tandem Reactions
Authors: Jin Ronghua , Zheng Dongsong , Liu Rui , Liu Guohua 
Published: December 2017

AbstractThe development of silica‐supported molecular catalysts for tandem reactions is an important research direction of heterogeneous catalysis. Besides their significant merits in sustainable catalytic processes, numerous strategies have been utilized to construct silica‐supported molecular catalysts. Here, we emphasize tandem reactions and summarize the recent advances in sequential organic transformations. This paper is composed of four parts. The beginning part introduces silica as supports. The second part provides a large number of examples for the construction of non‐chiral molecular catalysts used for tandem reactions. The third part offers an outline for the construction of chiral molecular catalysts used for enantioselective tandem reactions. Finally, the perspectives for the further development of silica‐supported molecular catalysts for tandem reactions are addressed.
Enhanced Turnover for the P450 119 Peroxygenase‐Catalyzed Asymmetric Epoxidation of Styrenes by Random Mutagenesis
Authors: Wang Li , Wei Siping , Pan Xianchao , Liu Pingxian , Du Xi , Zhang Chun , Pu Lin , Wang Qin 
Published: December 2017

AbstractA randomized library is constructed based on pET30a‐CYP119‐T214V plasmid. This library of random mutants of CYP119‐T214V was screened by means of the reduced CO difference spectra and epoxidation of styrene. By using directed evolution, a new CYP119 quadruple mutant S148P/I161T/K199E/T214V is constructed, expressed, and purified. This quadruple mutant significantly increases the turnover rate and conversion for the asymmetric epoxidation of styrene and its derivatives. The kcat. value of cis‐β‐methylstyrene epoxidation catalyzed by the quadruple mutant exhibits an approximately 10‐fold increase, relative to the previously reported T213M mutant under the same conditions. This is the first engineered CYP119 peroxygenase for the epoxidation of cis‐β‐methylstyrene with a high turnover rate. The proposed mechanism, on the basis of a molecular docking study, for the asymmetric epoxidation suggests that the introduction of an acidic amino acid side chain into the active site and a hydrophobic amino acid into the substrate channels of CYP119 peroxygenase might result in high efficiency for the formation of compound I, and its subsequent peroxygenation by reconstructing the hydrogen‐bonding interaction and increasing the substrate affinity and access.
The relationship between negative metacognitive thoughts, pain catastrophizing and adjustment to chronic pain
Authors: Ziadni M.S. , Sturgeon J.A. , Darnall B.D. 
Published: December 2017

AbstractBackgroundCognitive appraisals, most notably pain catastrophizing, play an important role in chronic pain. The role of metacognition and its impact on the relationship between pain catastrophizing and health are understudied. The identification of metacognition as a moderator of psychological constructs may have clinical and empirical implications. We hypothesized that negative metacognitive beliefs would moderate the relationships between pain catastrophizing and emotional functioning and physical activity.MethodParticipants (N = 211) with mixed aetiology chronic pain were primarily Caucasian females with severe average pain intensity. Over the course of 2 weeks, participants completed online daily‐diary measures of pain catastrophizing, pain intensity, mood, physical activity and metacognition.ResultsParticipants with higher average levels of daily pain intensity and negative metacognitive beliefs about worry reported higher levels of daily pain catastrophizing, as well as daily depression, and anxiety. Some aspects of metacognitive beliefs (i.e. dangerousness and uncontrollability of thoughts) were also negatively associated with average daily levels of positive affect. However, these effects were not interactive; metacognitive beliefs did not moderate the relationships of pain catastrophizing with other daily variables.ConclusionsFrom a daily coping perspective, findings reveal that people with stronger negative metacognitive beliefs report greater emotional distress on a day‐to‐day basis. However, negative metacognitive beliefs did not appear to modify the effects of pain catastrophizing on psychological and physical functioning at the daily level, suggesting that metacognitive beliefs may be better conceptualized as a more parallel indicator of emotional maladjustment to chronic pain whose effects do not reliably manifest in daily measurement models.SignificanceFindings highlight the need to better characterize the value of metacognitive beliefs as an important predictor and therapeutic target. Despite limited evidence of a dynamic relationship between metacognition and daily adjustment to chronic pain, results emphasize the potential importance of interventions that target cognitive appraisal process beyond catastrophizing, including uncontrollability and danger‐laden thought patterns.
Electrochemical Immunoassay for Salmonella Typhimurium Based on an Immuno‐magnetic Redox Label
Authors: Ngoensawat Umphan , Rijiravanich Patsamon , Surareungchai Werasak , Somasundrum Mithran 
Published: December 2017

AbstractWe have described a sensitive voltammetric immunoassay for Salmonella Typhimurium based on the employment of a dual‐function label. Methylene blue was adsorbed onto multi‐walled carbon nanotubes (MWCNTs) at a loading of 6.5×10−3 mol g−1, and these modified MWCNTs were then adsorbed onto carboxylic acid‐modified Fe2O3 magnetic particles of approx. diameter 1 μm. It was estimated from voltammetry that each magnetic particle delivered 2.3×108 molecules of methylene blue. Following adsorption of monoclonal anti‐Salmonella antibodies onto the particles, the particles were used for the immunomagnetic separation of Salmonella cells, which were then detected in a sandwich assay using methylene blue reduction at screen printed electrodes modified with polyclonal anti‐Salmonella antibodies. Calibration in buffer and in pasteurized milk (10 to 106 CFU mL−1) resulted in LODs of 7.9 CFU mL−1 and 17.3 CFU mL−1 respectively, without pre‐enrichment. The assay platform showed good discrimination against E. coli in both buffer and milk, and the label fabrication process was shown to be reproducible at a 95 % confidence limit as examined by analysis of variance. When stored at 4 °C the labels gave stable assay responses for a period of 60 days.
Analyzing Item Generation with Natural Language Processing Tools for the TOEIC® Listening Test
Authors: Yoon Su‐Youn , Lee Chong Min , Houghton Patrick , Lopez Melissa , Sakano Jennifer , Loukina Anastassia , Krovetz Bob , Lu Chi , Madnani Nitin 
Published: December 2017

AbstractIn this study, we developed assistive tools and resources to support TOEIC® Listening test item generation. There has recently been an increased need for a large pool of items for these tests. This need has, in turn, inspired efforts to increase the efficiency of item generation while maintaining the quality of the created items. We aimed to address this challenge by creating a set of automated tools and resources that support item generation: an automated system that retrieves appropriate real‐world videos, a list of vocabulary tagged with established difficulty levels, and a tool that suggests words and phrases that are similar in distribution to a given word (word similarity tool). These tools and resources were designed to help item writers by providing initial ideas, authentic language, and support for adjusting the variety and complexity of vocabulary in their items. To evaluate the impact of these resources on the efficiency of item generation, seven item writers created listening items using our tools. All tools were considered useful, and the word similarity tool in particular was rated the most useful. The tools are currently applied to English item generation for the TOEIC Listening test, but the method is generic and applicable to other languages.
New petrographic and geochemical tracers for recognizing the provenance quarry of trachyte of the Euganean Hills, northeastern Italy
Authors: Germinario Luigi , Hanchar John M. , Sassi Raffaele , Maritan Lara , Cossio Roberto , Borghi Alessandro , Mazzoli Claudio 
Published: December 2017

AbstractTrachyte of the Euganean Hills is a subvolcanic porphyritic rock historically used as carving and building stone in northern and central Italy–primarily from Roman times onward–with the first evidence of its use dating back to prehistory. The numerous quarries and very similar trachyte varieties, as well as the widespread use of this stone, create several problems in defining its provenance for archaeological and historical materials. New petrographic and geochemical tracers for recognizing the provenance quarry of Euganean trachyte are presented here, providing a comprehensive reference database for archaeometric studies. The petrographic markers principally include quantitative data on mineralogical composition and textural features of phenocrysts and groundmass, determined by image analysis of chemical maps acquired by micro X‐ray fluorescence and scanning electron microscope‐energy‐dispersive X‐ray spectroscopy; particular use has been made of data on the abundance and grain‐size distribution of feldspar phenocrysts, phenocrysts‐groundmass ratio, content of SiO2 phases in the groundmass, and the arrangement and grain‐size of microlites in the matrix. The geochemical tracers involve composition of bulk rock and phenocrysts, determined by X‐ray fluorescence and laser ablation inductively coupled plasma mass spectrometry, respectively; quarry recognition can be achieved using plots built from concentrations of major and trace elements, with mineral‐scale chemistry being the most effective and precise discriminant property, especially in the case of biotite and, secondarily, augite, kaersutite, and magnetite.
Field geology, geochronology, and isotope geochemistry of the Luyuangou gold deposit, China: Implications for the gold mineralization in the eastern Qinling Orogen
Authors: Lei Wanshan , Dai Jun , Zhao Taiping , Zhang Yanfei , Tao Ni 
Published: December 2017

Gold deposits are closely related to accretionary processes. Gold mineralization in eastern China, however, is usually > 100 Ma younger than associated collisional orogeny and partly controlled by extensional tectonics. Being controlled by interbedded detachment faults, the Luyuangou hydrothermal deposit is a typical mineralization under extensional tectonic. We present mineral deposit geology, tectonic geology, LA‐ICP MS zircon U–Pb age data, and Sr‐Nd‐Hf isotopic data for the Luyuangou ore vein and porphyritic dyke, with the aim of elucidating the metallogenesis. The morphological features and ages of zircons from the Luyuangou auriferous lode are similar to the anatectic zircons from migmatite within the Qinling Group (a metamorphic complex unit) of the North Qinling Terrane, indicating that the North Qinling Terrane may be one of the provenances. Although the major age peak of 453 ± 13 Ma (MSWD = 3.3,N = 12) cannot constrain the exact metallogenic timing, the data imply a possible link between the Luyuangou metallization and the North Qinling Terrane. Meanwhile, the weighted‐mean age of post‐ore porphyritic dyke postdates the Luyuangou gold mineralization at 121.1 ± 1.5 Ma (MSWD = 0.21,N = 14). The Sr‐Nd‐Hf isotopes of the Luyuangou auriferous lodes and post‐ore porphyritic dyke exhibit prominent differences from those of the Taihua Group and Xiong'er Group and are similar to those of the Qinling Group, implying that the Qinling Group is likely the main ore‐forming provenance of the Luyuangou gold deposit. The S‐Pb isotopes of the main mineralization stage of the Luyuangou gold deposit indicate a distinct deep‐seated source. According to comprehensive analysis, it is proposed that, during the early Mesozoic, the large‐scale continental collision between the Yangtze and the North China Craton involved the underthrusting of the North Qinling Terrane beneath the North China Craton that led to intracontinental folding, thrusting, and thickening without inducing extensive mineralization or magmatic activity. During the late Mesozoic, the subduction of the Pacific Plate induced the instability of the thickened continental crust and the development of the regional extensional structures, large‐scale crust–mantle magmatism as well as deep‐seated or mantle‐derived fluids dissolving materials from the Qinling Group that precipitated at the interbedded detachment faults.