bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seasonal, Monthly, and Weekly Distributions of NLDN and GLD360 Cloud-to-Ground Lightning
Authors: Holle Ronald L. , Cummins Kenneth L. , Brooks William A. 
Published: May 2016

Abstract
Annual maps of cloud-to-ground lightning flash density have been produced since the deployment of the National Lightning Detection Network (NLDN). However, a comprehensive national summary of seasonal, monthly, and weekly lightning across the contiguous United States has not been developed. Cloud-to-ground lightning is not uniformly distributed in time, space, or frequency. Knowledge of these variations is useful for understanding meteorological processes responsible for lightning occurrence, planning outdoor events, anticipating impacts of lightning on power reliability, and relating to severe weather. To address this gap in documentation of lightning occurrence, the variability on seasonal, monthly, and weekly scales is first addressed with NLDN flash data from 2005 to 2014 for the 48 states and adjacent regions. Flash density and the percentage of each season’s portion of the annual total are compiled. In spring, thunderstorms occur most often over southeastern states. Lightning spreads north and west until by June, most areas have lightning. New England, the northern Rockies, most of Canada, and the Florida Peninsula have a small percentage of lightning outside of summer. Arizona and portions of adjacent states have the highest incidence in July and August. Flash densities reduce in September in most regions. This seasonal, monthly, and weekly overview complements a recent study of diurnal variations of flashes to document when and where lightning occurs over the United States. NLDN seasonal maps indicate a summer lightning dominance in the northern and western United States that extends into Canada using data compiled from GLD360 network observations. GLD360 also extends NLDN seasonal maps and percentages into Mexico, the Caribbean, and offshore regions.
Is erythropoietin a worthy candidate for traumatic brain injury or are we heading the wrong way?
Authors: Grasso Giovanni , Alafaci Concetta , Ghezzi Pietro 
Published: May 2016

Traumatic brain injury (TBI) is a leading cause of death and disability in the modern society. Although primary prevention is the only strategy that can counteract the primary brain damage, numerous preclinical studies have been accumulated in order to find therapeutic strategies against the secondary damage. In this scenario erythropoietin (EPO) has been shown to be a promising candidate as neuroprotective agent. A recent clinical trial, however, has shown that EPO has not an overall effect on outcomes following TBI thus renewing old concerns. However, the results of a prespecified sensitivity analysis indicate that the effect of EPO on mortality remains still unclear. In the light of these observations, further investigations are needed to resolve doubts on EPO effectiveness in order to provide a more solid base for tailoring conclusive clinical trials.
Learning bodies engaging with art: Staging aesthetic experiences in museum education
Authors: Illeris Helene 
Published: May 2016

Abstract
How can we stimulate encounters between students and artworks that are both sensuous, meaningful and transformational? How can we involve students’ bodies in aesthetic experiences in art museums? Inspired by Richard Shusterman the article focuses on three dimensions of the aesthetic experience: the phenomenological, the semantic and the transformational. Together with Judith Butler’s concepts of performativity and performance, these notions are used to discuss the role of ‘the learning body’ in three case studies carried out in art museums over a ten-year period. The study sheds light on how the concept of aesthetic experience can be used for understanding the pedagogical value of encounters between young people and contemporary art. Another aim is to show how the body as locus for aesthetic experiences can challenge traditional understandings of the learning body and to discuss how to develop performative forms of art education that actively involves students’ bodies.
Transformer species in the flora of the Starobilsk grass-meadow steppe (Ukraine)
Authors: Kucher Oksana O. 
Published: May 2016

Abstract
The results of an investigation of alien species that change the character, condition, form or nature of ecosystems over large areas (transformer species) in the flora of the Starobilsk grass-meadow steppe are presented. The check-list of alien plants includes over 386 species of vascular plants, of which 28 are invasive and 6 are transformer species. In this study, the data on the first records of alien species, their distribution history, ecology, occurrence in different plant communities and degree of naturalization were compiled. The distribution maps of transformer species are provided.
Synthesis of 6-alkylsulfanyl-1,4-dihydropyridines as potential multidrug resistance modulators
Authors: Krauze Aivars , Krasnova Laura , Grinberga Signe , Sokolova Elina , Domracheva Ilona , Shestakova Irina , Duburs Gunars 
Published: May 2016

Abstract
6-Alkylsulfanyl-1,4-dihydropyridines 5 bearing methoxyphenyl groups at various positions have been prepared by three different approaches. Multidrug resistance modulating (P-glycoprotein and multidrug resistance protein-1 inhibition) activity of 1,4-dihydropyridine derivatives 5 is comparable to that of verapamil.
Textural features of the beach sediments of Wast Water Lake, Northwest England
Authors: Bala Emilia 
Published: May 2016

Abstract
This study is dedicated to Wast Water Lake (Northwest England, Great Britain) and the character of its beach sediments. The aim of the study is to identify the textural features of the lake’s beach sediments based on two methods. The first is a granulometric analysis and the second a pebble shape analysis according to Zingg (1935) and Sneed & Folk (1958). Both analyses were carried out for all of the lake’s accessible beaches and the cliffs adjacent to them. The transport and deposition history of the examined sediments was identified through field research and laboratory analysis. The results show that the textural features of the sediments at Wast Water are more often typical of a fluvial environment, rather than having been changed by lacustrine water movements.
Buffering of Genetic Regulatory Networks inDrosophila melanogaster
Authors: Fear Justin M , León-Novelo Luis G , Morse Alison M , Gerken Alison R , Van Lehmann Kjong , Tower John , Nuzhdin Sergey V , McIntyre Lauren M 
Published: May 2016

AbstractRegulatory variation in gene expression can be described by cis- and trans-genetic components. Here we used RNA-seq data from a population panel of Drosophila melanogaster test crosses to compare allelic imbalance (AI) in female head tissue between mated and virgin flies, an environmental change known to affect transcription. Indeed, 3048 exons (1610 genes) are differentially expressed in this study. A Bayesian model for AI, with an intersection test, controls type I error. There are ∼200 genes with AI exclusively in mated or virgin flies, indicating an environmental component of expression regulation. On average 34% of genes within a cross and 54% of all genes show evidence for genetic regulation of transcription. Nearly all differentially regulated genes are affected in cis, with an average of 63% of expression variation explained by the cis-effects. Trans-effects explain 8% of the variance in AI on average and the interaction between cis and trans explains an average of 11% of the total variance in AI. In both environments cis- and trans-effects are compensatory in their overall effect, with a negative association between cis- and trans-effects in 85% of the exons examined. We hypothesize that the gene expression level perturbed by cis-regulatory mutations is compensated through trans-regulatory mechanisms, e.g., trans and cis by trans-factors buffering cis-mutations. In addition, when AI is detected in both environments, cis-mated, cis-virgin, and trans-mated–trans-virgin estimates are highly concordant with 99% of all exons positively correlated with a median correlation of 0.83 for cis and 0.95 for trans. We conclude that the gene regulatory networks (GRNs) are robust and that trans-buffering explains robustness.
CLIP‐COSY: Reine Inphase‐Signale und schnelle Akquisition COSY‐artiger Korrelationen
Authors: Koos Martin R. M. , Kummerlöwe Grit , Kaltschnee Lukas , Thiele Christina M. , Luy Burkhard 
Published: May 2016

AbstractDas COSY ist ein wichtiges homonukleares 2D‐NMR‐Experiment zur Zuordnung von Resonanzen. Die Multiplettstruktur seiner Kreuzsignale ist jedoch häufig kompliziert, bedingt eine geringe Signalintensität und erfordert lange Aufnahmezeiten. Wir stellen das CLIP‐COSY vor, ein COSY‐artiges Experiment, das reine Inphase‐Signale erzeugt. Es verstärkt die Intensität der meisten Kreuzsignale und kann in wenigen Minuten aufgenommen werden. Durch Kombination mit nicht‐äquidistantem Abtasten (NUS) kann die Messzeit weiter reduziert werden und die Inphase‐Natur der Signale erlaubt den Einsatz homonuklearer Entkopplungsmethoden. Da beim CLIP‐COSY keine Auslöschung von Antiphase‐Komponenten stattfindet, kann das CLIP‐COSY auch bei Makromolekülen und anderen Systemen mit breiten Linien angewendet werden.
An All‐Solid‐State Fiber‐Shaped Aluminum–Air Battery with Flexibility, Stretchability, and High Electrochemical Performance
Authors: Xu Yifan , Zhao Yang , Ren Jing , Zhang Ye , Peng Huisheng 
Published: May 2016

AbstractOwing to the high theoretical energy density of metal–air batteries, the aluminum–air battery has been proposed as a promising long‐term power supply for electronics. However, the available energy density from the aluminum–air battery is far from that anticipated and is limited by current electrode materials. Herein we described the creation of a new family of all‐solid‐state fiber‐shaped aluminum–air batteries with a specific capacity of 935 mAh g−1 and an energy density of 1168 Wh kg−1. The synthesis of an electrode composed of cross‐stacked aligned carbon‐nanotube/silver‐nanoparticle sheets contributes to the remarkable electrochemical performance. The fiber shape also provides the aluminum–air batteries with unique advantages; for example, they are flexible and stretchable and can be woven into a variety of textiles for large‐scale applications.
Enantiodivergent Combination of Natural Product Scaffolds Enabled by Catalytic Enantioselective Cycloaddition
Authors: Xu Hao , Golz Christopher , Strohmann Carsten , Antonchick Andrey P. , Waldmann Herbert 
Published: May 2016

AbstractAn efficient strategy has been established for the enantiodivergent synthesis of natural product inspired compounds embodying both tropane and pyrrolidine natural product fragments. This strategy includes the enantioselective kinetic resolution of racemic tropanes by means of a copper(I)‐catalyzed [3+2] cycloaddition and allows the preparation of two enantiopure products in a one‐pot reaction in high yield and with high diastereo‐ and enantioselectivity by using one chiral catalyst.
Chiral Nanoparticles/Lewis Acids as Cooperative Catalysts for Asymmetric 1,4‐Addition of Arylboronic Acids to α,β‐Unsaturated Amides
Authors: Yasukawa Tomohiro , Saito Yuuki , Miyamura Hiroyuki , Kobayashi Shū 
Published: May 2016

AbstractCooperative catalysts consisting of chiral Rh/Ag nanoparticles and Sc(OTf)3 have been developed that catalyze asymmetric 1,4‐addition reactions of arylboronic acids with α,β‐unsaturated amides efficiently. The reaction has been considered one of the most challenging reactions because of the low reactivity of the amide substrates. The new catalysts provide the desired products with outstanding enantioselectivities (>98 % ee) in the presence of low loadings (<0.5 mol %) of the catalyst.
Epoxy/p‐phenylenediamine functionalized graphene oxide composites and evaluation of their fracture toughness and tensile properties
Authors: Hussein Abdelrahman , Sarkar Sourav , Oh Dongkwon , Lee Kwangju , Kim Byungki 
Published: May 2016

ABSTRACTIn an attempt to enhance the mechanical properties of epoxy/graphene‐based composites, the interface was engineered through the functionalization of graphene oxide (GO) sheets with p‐phenylenediamine; this resulted in p‐phenylenediamine functionalized graphene oxide (GO–pPDA). The morphology and chemical structure of the GO–pPDA sheets were studied by spectroscopic methods, thermal analysis, X‐ray diffraction, and transmission electron microscopy. The characterization results show the successful covalent functionalization of GO sheets through the formation of amide bonds. In addition, p‐phenylenediamine were polymerized on graphene sheets to form crystalline nanospheres; this resulted in a GO/poly(p‐phenylenediamine) hybrid. The mechanical properties of the epoxy/GO–pPDA composite were assessed. Although the Young's modulus showed improvement, more significant improvements were observed in the strength, fracture strain, and plane‐strain fracture toughness. These improvements were attributed to the unique microstructure and strong interface between GO–pPDA and the epoxy matrix. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43821.
Functional polymer from high molecular weight linear polyols and polyurethane‐based crosslinking units: Synthesis, characterization, and boron retention properties
Authors: Palencia Manuel , Restrepo Diego F , Combatt Enrique 
Published: May 2016

ABSTRACTThe objective of this work was to synthesize functional polymers, with boron removal properties, from high molecular weight linear polyols based on N‐methyl‐d‐glucamine (NMDG) and polyurethane units as crosslinking reagent. For that, (4‐vinylbenzyl)‐N‐methyl‐d‐glucamine monomer (VbNMDG) was synthesized from vinylbenzyl chloride and NMDG, and subsequently, high molecular weight linear poly(VbNMDG) was obtained by radical free polymerization. Later, polymer dots were obtained from poly(VbNMDG) and urethanization reactions using methylene diphenyl diisocyanate at room temperature. Monomers and polymers were characterized by different techniques (FTIR, DLS, elemental analysis, H1‐NMR). In addition, boron retention properties were studied by diafiltration technique using the azomethine‐H method. It was concluded that synthesis of polymer dots, with high boron retention capacity, can be easily synthesized by procedure described. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43895.
The Oxygen Dilemma: A Severe Challenge for the Application of Monooxygenases?
Authors: Holtmann Dirk , Hollmann Frank 
Published: May 2016

AbstractMonooxygenases are promising catalysts because they in principle enable the organic chemist to perform highly selective oxyfunctionalisation reactions that are otherwise difficult to achieve. For this, monooxygenases require reducing equivalents, to allow reductive activation of molecular oxygen at the enzymes' active sites. However, these reducing equivalents are often delivered to O2 either directly or via a reduced intermediate (uncoupling), yielding hazardous reactive oxygen species and wasting valuable reducing equivalents. The oxygen dilemma arises from monooxygenases' dependency on O2 and the undesired uncoupling reaction. With this contribution we hope to generate a general awareness of the oxygen dilemma and to discuss its nature and some promising solutions.
Structural Diversification of Lyngbyatoxin A by Host‐Dependent Heterologous Expression of the tleABC Biosynthetic Gene Cluster
Authors: Zhang Lihan , Hoshino Shotaro , Awakawa Takayoshi , Wakimoto Toshiyuki , Abe Ikuro 
Published: May 2016

AbstractNatural products have enormous structural diversity, yet little is known about how such diversity is achieved in nature. Here we report the structural diversification of a cyanotoxin—lyngbyatoxin A—and its biosynthetic intermediates by heterologous expression of the Streptomyces‐derived tleABC biosynthetic gene cluster in three different Streptomyces hosts: S. lividans, S. albus, and S. avermitilis. Notably, the isolated lyngbyatoxin derivatives, including four new natural products, were biosynthesized by crosstalk between the heterologous tleABC gene cluster and the endogenous host enzymes. The simple strategy described here has expanded the structural diversity of lyngbyatoxin A and its biosynthetic intermediates, and provides opportunities for investigation of the currently underestimated hidden biosynthetic crosstalk.
Rhodium‐Catalyzed/Copper‐Mediated Selective C2 Alkynylation of Indoles and C1 Alkynylation of Carbazoles with γ‐Substituted tert‐Propargyl Alcohols
Authors: Li Ting , Wang Zhen , Qin Wen‐Bing , Wen Ting‐Bin 
Published: May 2016

AbstractA novel rhodium‐catalyzed/copper‐mediated C2‐selective C−H alkynylation of indoles using γ‐substituted tert‐propargyl alcohols as the alkynylating reagent and a removable 6‐methylpyridin‐2‐yl as the directing group has been developed, which provides a viable pathway for direct C2‐selective alkynylation of indoles. Moreover, this strategy could be extended to the C−H alkynylation of carbazoles at the C1 position.
Water Oxidation by Copper–Amino Acid Catalysts at Low Overpotentials
Authors: Lu Cui , Wang Jianying , Chen Zuofeng 
Published: May 2016

AbstractAlthough notable progress has been made in developing first‐row transition‐metals‐based water oxidation catalysts, continuous efforts are required to identify more inexpensive, efficient, and robust catalysts. Here, we demonstrate the utility of a series of readily available complexes formed by earth‐abundant copper and amino acids as catalyst precursors. In phosphate solution at pH 12, electrolysis with 1 mm CuII and 4 mm Gly results in in situ formation of an amorphous surface precipitate of a CuO/Cu(OH)2 mixture, which incorporates a substantial amount of phosphate anions. This surface‐bound solid can catalyze water oxidation with an impressive onset overpotential of 380 mV, an overpotential of 450 mV for a current density of 1 mA cm−2, and a low Tafel slope of 64 mV dec−1, which make it among the most active Cu‐based heterogeneous electrocatalysts. The copper‐based reactivity toward water oxidation is shared by CuII complexation to other amino acids as catalyst precursors.
Rapid‐Scan Operando Infrared Spectroscopy
Authors: Davó‐Quiñonero Arantxa , Bueno‐López Agustín , Lozano‐Castelló Dolores , McCue Alan J. , Anderson James A. 
Published: May 2016

AbstractNovel methodology, referred to as rapid‐scan operando, has been demonstrated to be a highly powerful tool for studying reaction mechanisms in heterogeneous catalysis, because it combines rapid scan for IR monitoring in the milliseconds time frame and operando methodology. As proof of concept, the NOx–CO and NOx–H2 reactions were studied as model catalyzed reactions with practical interest for removal of NOx in diesel exhausts. Rapid‐scan operando experiments confirmed state‐of‐the‐art knowledge concerning the reaction mechanisms and, more importantly, allowed us to elucidate, for the first time, the different roles of the surface hydroxy groups depending on the reductant used (CO or H2). Moreover, this new tool was used to distinguish the behavior of carbonates and nitrites under reaction conditions that could not be monitored by conventional IR spectroscopy approaches owing to overlap of their absorbance bands.
Asymmetric Reductive Amination of Ketones Catalyzed by Imine Reductases
Authors: Wetzl Dennis , Gand Martin , Ross Alfred , Müller Hubertus , Matzel Philipp , Hanlon Steven P. , Müller Michael , Wirz Beat , Höhne Matthias , Iding Hans 
Published: May 2016

AbstractBiocatalysis employing imine reductases is a promising approach for the one‐step generation of chiral amines from ketones. The enzymes reported for this process suffer from low activity and moderate stereoselectivity. We identified a set of enzymes that facilitate this reaction with high to quantitative conversions from a library of 28 imine reductases. This enabled the conversion of ketones with ammonia, methylamine, or butylamine into the corresponding amines. Most importantly, we performed preparative (>100 mg) scale syntheses of amines such as (1S,3R)‐N,3‐dimethylcyclohexylamine and (R)‐N‐methyl‐2‐aminohexane with excellent stereochemical purities (98 % de, 96 % ee) in good yields.
ChemInform Abstract: A New Structure Family of Ternary Germanides: RIrGe2 (R: Y, Pr‐Sm, Gd‐Er) and MPtGe2 (M: Ca, Y, Ce‐Sm, Gd‐Tm).
Authors: FRANCOIS M. , VENTURINI G. , MCRAE E. , MALAMAN B. , ROQUES B. 
Published: May 2016

AbstractThe new isostructural germanides have been prepared from stoichiometric mixtures of the elements at 1173 K. YIrGe2, which has been characterized by single‐crystal XRD, crystallizes in the orthorhombic space group Immm, Z = 8. The structure is closely related to the Sc5Co4Si10‐type.
ChemInform Abstract: Thermodynamic Properties and Phase Equilibria of the Lead‐Tellurium Binary System.
Authors: NGAI T. L. , MARSHALL D. , SHARMA R. C. , CHANG Y. A. 
Published: May 2016

AbstractThe liquidus curve of the Pb‐Te binary system has been determined by DTA (employing a small, (0.2 g) as well as a large (5 g) sample) and by chemical analysis.
ChemInform Abstract: Structural Study of Monosubstituted β‐Cyclodextrins. Crystal Structures of Phenylthio‐β‐cyclodextrin and Phenylsulfinyl‐β‐cyclodextrin and Spectroscopic Study of Related Compounds in Aqueous Solution.
Authors: KAMITORI S. , HIROTSU K. , HIGUCHI T. , FUJITA K. , YAMAMURA H. , IMOTO T. , TABUSHI I. 
Published: May 2016

AbstractX‐ray structural analysis of (Ia) and (Ib) gives space group P41212 with Z = 8 and P212121 with Z=4, respectively.
ChemInform Abstract: Cleavage of the Oxygen Bridge in 8‐Oxabicyclo(3.2.1)octan‐3‐ones and ‐oct‐6‐en‐3‐ones by Trimethylsilyl Trifluoromethanesulfonate.
Authors: FOEHLISCH B. + , SENDELBACH S. , BAUER H. 
Published: May 2016

AbstractTreatment of the title compounds (I) and (V) with (IV) results in cleavage of the oxygen bridge to afford the monocyclic products (II) and (VI).
ChemInform Abstract: Selectivity and Charge Transfer in Photoreactions of Donor‐Acceptor Systems. Part 8. Photochemical Cycloadditions of 1,3‐Dioxoles to Anisole.
Authors: MATTAY J. , RUNSINK J. , PICCIRILLI J. A. , JANS A. W. H. , CORNELISSE J. 
Published: May 2016

AbstractPhotolysis of anisole (I) with the dioxoles (II) results in the formation of the dimerization products (III) ((IIIa) is identified as the trans‐isomer, (IIIb) as a cis‐trans mixture) and the cyclo‐adducts (IV)‐(VII).
ChemInform Abstract: Dehydration of Carboxamides to Nitriles with a Zirconia Catalyst.
Authors: JOSHI G. W. , RAJADHYAKSHA R. A. 
Published: May 2016

AbstractThe dehydration of the carboxamides (I), yielding the nitriles (II), is carried out in various solvents in the presence of a zirconia catalyst which has already been described.
ChemInform Abstract: Reactions of Tetrafluoroethene Oligomers. Part 6. Some Reactions of 4‐Diazo‐1,1,1,2,2‐pentafluoro‐3‐pentafluoroethyl‐3‐trifluoromethylbutane.
Authors: COE P. L. , COOK M. I. , GOODCHILD N. J. , EDWARDS P. N. 
Published: May 2016

AbstractThe diazoalkane (III) is prepared from the isocyanate (I) via the salt (II).
ChemInform Abstract: Fluorohalogeno Compounds. Part 2. Sonochemical Approach to 3,3,3‐Trifluoropropionic Acids.
Authors: HEMER I. , HAVLICEK J. , DEDEK V. 
Published: May 2016

AbstractThe fluoropropionic acids (II) are synthesized by ultrasound‐promoted reaction of the trihaloethanes (I) with zinc and carbon dioxide.
ChemInform Abstract: Polymer Supported Acetylaminophenoxide Anion: Convenient Method for O‐Alkylation.
Authors: SALUNKHE D. G. , JAGDALE M. H. , SHINDE S. S. , SALUNKHE M. M. 
Published: May 2016

AbstractThe reaction of acetylaminophenoxide supported on Amberlyst A‐26 with the halides (II) represents an easy method for the synthesis of the O‐alkylated products (III) in high yields.