bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hierarchical Fabric Decorated with Carbon Nanowire/Metal Oxide Nanocomposites for 1.6 V Wearable Aqueous Supercapacitors
Authors: Fu Wenbin , Zhao Enbo , Ren Xiaolei , Magasinski Alexandre , Yushin Gleb 
Published: February 2018

AbstractAqueous asymmetric supercapacitors (ASCs) may offer comparable or higher energy density than electric double‐layer capacitors (EDLCs) based on organic electrolytes. As such, ASCs may be more suitable for integration into smart textiles, where the use of flammable organic solvents is not acceptable. However, reported ASC devices typically suffer from poor rate capability and low areal loadings. This study demonstrates the development of nitrogen‐doped carbon (N‐C) nanowire/metal oxide (Fe2O3 and MnO2) nanocomposite electrodes directly produced on the internal surface of a conductive fabric for use as high‐rate electrodes for solid‐state ASCs. The N‐C nanowires provide fast and efficient pathways for electrons, while short diffusion paths within nanosized metal oxides enable fast ion transport, leading to greatly enhanced performance at high rates. The porous structure of the fabric enables high areal capacitance loading in each electrode (≈150 mF cm−2). Both electrodes show high specific capacitance of ≈180 F g−1 (Fe2O3) and ≈250 F g−1 (MnO2) and excellent rate capability. Solid‐state ASCs assembled by using an aqueous gel electrolyte operate at 1.6 V and deliver over 60 mF cm−2 during ≈50 s charging/discharging time and over 30 mF cm−2 for ≈5 s discharge.
Mutations in SCN3A cause early infantile epileptic encephalopathy
Authors: Zaman Tariq , Helbig Ingo , Božović Ivana Babić , DeBrosse Suzanne D. , Bergqvist A. Christina , Wallis Kimberly , Medne Livija , Maver Aleš , Peterlin Borut , Helbig Katherine L. , Zhang Xiaohong , Goldberg Ethan M. 
Published: February 2018

ObjectiveVoltage‐gated sodium (Na+) channels underlie action potential generation and propagation and hence are central to the regulation of excitability in the nervous system. Mutations in the genes SCN1A, SCN2A, and SCN8A, encoding the Na+ channel pore‐forming (α) subunits Nav1.1, 1.2, and 1.6, respectively, and SCN1B, encoding the accessory subunit β1, are established causes of genetic epilepsies. SCN3A, encoding Nav1.3, is known to be highly expressed in brain, but has not previously been linked to early infantile epileptic encephalopathy. Here, we describe a cohort of 4 patients with epileptic encephalopathy and heterozygous de novo missense variants in SCN3A (p.Ile875Thr in 2 cases, p.Pro1333Leu, and p.Val1769Ala).MethodsAll patients presented with treatment‐resistant epilepsy in the first year of life, severe to profound intellectual disability, and in 2 cases (both with the variant p.Ile875Thr), diffuse polymicrogyria.ResultsElectrophysiological recordings of mutant channels revealed prominent gain of channel function, with a markedly increased amplitude of the slowly inactivating current component, and for 2 of 3 mutants (p.Ile875Thr and p.Pro1333Leu), a leftward shift in the voltage dependence of activation to more hyperpolarized potentials. Gain of function was not observed for Nav1.3 variants known or presumed to be inherited (p.Arg1642Cys and p.Lys1799Gln). The antiseizure medications phenytoin and lacosamide selectively blocked slowly inactivating over transient current in wild‐type and mutant Nav1.3 channels.InterpretationThese findings establish SCN3A as a new gene for infantile epileptic encephalopathy and suggest a potential pharmacologic intervention. These findings also reinforce the role of Nav1.3 as an important regulator of neuronal excitability in the developing brain, while providing additional insight into mechanisms of slow inactivation of Nav1.3. Ann Neurol 2018;83:703–717
Herstellung direkt nutzbarer Durchflussreaktorkartuschen durch 3D‐Druck von thermostabilen Enzymen
Authors: Maier Manfred , Radtke Carsten P. , Hubbuch Jürgen , Niemeyer Christof M. , Rabe Kersten S. 
Published: February 2018

AbstractDie Kompartimentierung chemischer Reaktionen ist ein grundlegendes Prinzip des Lebens und daher ein wichtiger Ausgangspunkt für Innovationen bei der Entwicklung neuer Ansätze in der Biokatalyse. Zur Implementierung von Biotransformationen in räumlich getrennten Kompartimenten werden daher Herstellungsmethoden benötigt, die die schnelle Produktion von in Flusssystemen einsetzbaren Biokatalysatoren erlauben. Dreidimensionale (3D) Drucktechniken bieten eine solche hohe Durchsatzleistung, sind aber normalerweise nicht mit der empfindlichen Natur von Enzymen kompatibel, die physiologische Verarbeitungsparameter erfordern. Wir zeigen hier die Anwendung thermostabiler Enzyme zur Realisierung biokatalytischer, Agarose‐basierter Tinten, die in einem einfachen temperaturgesteuerten 3D‐Druckprozess angewendet werden können. Als Beispiele haben wir eine Esterase (EstII) und eine Alkoholdehydrogenase (ADH) aus thermophilen Organismen verwendet sowie eine Decarboxylase, die durch gerichtete Proteinevolution thermostabilisiert wurde. Die resultierenden 3D‐gedruckten Kartuschen wurden anschließend für eine kontinuierliche, zweistufige sequentielle Biotransformation in einem fluidischen Setup angewendet.
Strukturelle Untersuchung subviraler Partikel durch die Kombination von zellfreier Proteinherstellung mit 110 kHz MAS‐NMR‐Spektroskopie
Authors: David Guillaume , Fogeron Marie‐Laure , Schledorn Maarten , Montserret Roland , Haselmann Uta , Penzel Susanne , Badillo Aurélie , Lecoq Lauriane , André Patrice , Nassal Michael , Bartenschlager Ralf , Meier Beat H. , Böckmann Anja 
Published: February 2018

AbstractVirale Membranproteine sind vorrangige Ziele bei der Bekämpfung von Infektionen. Ihre Strukturbestimmung bleibt jedoch eine Herausforderung, sowohl in Bezug auf die Probenvorbereitung als auch auf die Methodologie der Strukturanalyse von Proteinen in einer Lipidmembranumgebung. Zellfreie Proteinherstellung und Festkörper‐NMR‐Spektroskopie sind vielversprechende Ansätze in diesem Zusammenhang, der erstere in Bezug auf das hohe Potenzial, komplexe Proteine in nativer Form herzustellen und der letztere für die Fähigkeit, Proteine in Lipiden analysieren zu können. Wir zeigen hier, dass mg‐Mengen des kleinen Hüllproteins des Enten‐Hepatitis‐B‐Virus (DHBV) mittels zellfreier Herstellung produziert werden können, und dass die Proteine zu subviralen Partikeln zusammenlagern. Protonendetektierte 2D‐NMR‐Spektren, die bei 110 kHz schneller Probenrotation um den magischen Winkel und mit <500 μg Protein aufgenommen wurden, zeigen eine Reihe von isolierten Signalen mit Linienbreiten, die vergleichbar zu denen von Modellmembranproteinen sind. Dies ebnet den Weg für strukturelle Studien dieser komplexen supramolekularen Proteinsysteme, die Homologe eines wichtigen Zielproteins für Arzneimittel in der HBV‐Infektion sind.
NiH‐Catalyzed Reductive Relay Hydroalkylation: A Strategy for the Remote C(sp3)−H Alkylation of Alkenes
Authors: Zhou Fang , Zhu Jin , Zhang Yao , Zhu Shaolin 
Published: February 2018

AbstractThe terminal‐selective, remote C(sp3)−H alkylation of alkenes was achieved by a relay process combining NiH‐catalyzed hydrometalation, chain walking, and alkylation. This method enables the construction of unfunctionalized C(sp3)−C(sp3) bonds under mild conditions from two simple feedstock chemicals, namely olefins and alkyl halides. The practical value of this transformation is further demonstrated by the large‐scale and regioconvergent alkylation of isomeric mixtures of olefins at low catalyst loadings.
Lewis Acid Catalyzed Enantioselective Desymmetrization of Donor–Acceptor meso‐Diaminocyclopropanes
Authors: Perrotta Daniele , Wang Ming‐Ming , Waser Jérôme 
Published: February 2018

AbstractThe first Lewis acid catalyzed enantioselective ring‐opening desymmetrization of a donor–acceptor meso‐diaminocyclopropane is reported. The copper(II)‐catalyzed Friedel–Crafts alkylation of indoles and one pyrrole with an unprecedented meso‐diaminocyclopropane delivered enantioenriched, diastereomerically pure urea products, which are structurally related to natural and synthetic bioactive compounds. The development of a new ligand through the investigation of an underexplored subclass of bis(oxazoline) ligands was essential for achieving high enantioselectivities.
Direct Formation of C−C Triple‐Bonded Structural Motifs by On‐Surface Dehalogenative Homocouplings of Tribromomethyl‐Substituted Arenes
Authors: Sun Qiang , Yu Xin , Bao Meiling , Liu Mengxi , Pan Jinliang , Zha Zeqi , Cai Liangliang , Ma Honghong , Yuan Chunxue , Qiu Xiaohui , Xu Wei 
Published: February 2018

AbstractOn‐surface synthesis shows significant potential in constructing novel nanostructures/nanomaterials, which has been intensely studied in recent years. The formation of acetylenic scaffolds provides an important route to the fabrication of emerging carbon nanostructures, including carbyne, graphyne, and graphdiyne, which feature chemically vulnerable sp‐hybridized carbon atoms. Herein, we designed and synthesized a tribromomethyl‐substituted compound. By using a combination of high‐resolution scanning tunneling microscopy, non‐contact atomic force microscopy, and density functional theory calculations, we demonstrated that it is feasible to convert these compounds directly into C−C triple‐bonded structural motifs by on‐surface dehalogenative homocoupling reactions. Concurrently, sp3‐hybridized carbon atoms are converted into sp‐hybridized ones, that is, an alkyl group is transformed into an alkynyl moiety. Moreover, we achieved the formation of dimer structures, one‐dimensional molecular wires, and two‐dimensional molecular networks on Au(111) surfaces, which should inspire further studies towards two‐dimensional graphyne structures.
Wirklich grüne Synthese von Artemisinin aus Pflanzenextrakt
Authors: Triemer Susann , Gilmore Kerry , Vu Giang T. , Seeberger Peter H. , Seidel‐Morgenstern Andreas 
Published: February 2018

AbstractDurch den Einsatz von Pflanzenextrakten als Reaktionsmedium für chemische Synthesen können hocheffiziente und nachhaltige Prozesse erzielt werden. Dieses Prinzip wird auf die Partialsynthese von Artemisinin angewendet, ein sekundärer Metabolit der Pflanze Artemisia annua und eine wichtige Vorstufe von hochwirksamen Malariamedikamenten. Extrakte von A. annua enthalten außer Artemisinin auch als Abfallprodukte angesehene Komponenten, wie Dihydroartemisininsäure, die letzte Vorstufe von Artemisinin in der Biosynthese, und Chlorophyll, das als Photosensibilisator wirkt. Durch intensive Beleuchtung des unaufgearbeiteten Extrakts mit sichtbarem Licht wird Artemisinin in einem kontinuierlichen Durchflussreaktor in hoher Ausbeute aus dem Extrakt erzeugt. Dieser an der Biosynthese angelehnte Prozess ist dabei hocheffizient und nachhaltiger als etablierte Prozesse auf der Basis reiner Substanzen.
Dioxygen Sensitivity of [Fe]‐Hydrogenase in the Presence of Reducing Substrates
Authors: Huang Gangfeng , Wagner Tristan , Ermler Ulrich , Bill Eckhard , Ataka Kenichi , Shima Seigo 
Published: February 2018

AbstractMono‐iron hydrogenase ([Fe]‐hydrogenase) reversibly catalyzes the transfer of a hydride ion from H2 to methenyltetrahydromethanopterin (methenyl‐H4MPT+) to form methylene‐H4MPT. Its iron guanylylpyridinol (FeGP) cofactor plays a key role in H2 activation. Evidence is presented for O2 sensitivity of [Fe]‐hydrogenase under turnover conditions in the presence of reducing substrates, methylene‐H4MPT or methenyl‐H4MPT+/H2. Only then, H2O2 is generated, which decomposes the FeGP cofactor; as demonstrated by spectroscopic analyses and the crystal structure of the deactivated enzyme. O2 reduction to H2O2 requires a reductant, which can be a catalytic intermediate transiently formed during the [Fe]‐hydrogenase reaction. The most probable candidate is an iron hydride species; its presence has already been predicted by theoretical studies of the catalytic reaction. The findings support predictions because the same type of reduction reaction is described for ruthenium hydride complexes that hydrogenate polar compounds.
Iron‐Catalyzed Cross‐Couplings in the Synthesis of Pharmaceuticals: In Pursuit of Sustainability
Authors: Piontek Aleksandra , Bisz Elwira , Szostak Michal 
Published: February 2018

AbstractThe scarcity of precious metals has led to the development of sustainable strategies for metal‐catalyzed cross‐coupling reactions. The establishment of new catalytic methods using iron is attractive owing to the low cost, abundance, ready availability, and very low toxicity of iron. In the last few years, sustainable methods for iron‐catalyzed cross‐couplings have entered the critical area of pharmaceutical research. Most notably, iron is one of the very few metals that have been successfully field‐tested as highly effective base‐metal catalysts in practical, kilogram‐scale industrial cross‐couplings. In this Minireview, we critically discuss the strategic benefits of using iron catalysts as green and sustainable alternatives to precious metals in cross‐coupling applications for the synthesis of pharmaceuticals. The Minireview provides an essential introduction to the fundamental aspects of practical iron catalysis, highlights areas for improvement, and identifies new fields to be explored.
Revealing the Active Species for Aerobic Alcohol Oxidation by Using Uniform Supported Palladium Catalysts
Authors: Xin Pingyu , Li Jia , Xiong Yu , Wu Xi , Dong Juncai , Chen Wenxing , Wang Yu , Gu Lin , Luo Jun , Rong Hongpan , Chen Chen , Peng Qing , Wang Dingsheng , Li Yadong 
Published: February 2018

AbstractThe active species in supported metal catalysts are elusive to identify, and large quantities of inert species can cause significant waste. Herein, using a stoichiometrically precise synthetic method, we prepare atomically dispersed palladium–cerium oxide (Pd1/CeO2) and hexapalladium cluster–cerium oxide (Pd6/CeO2), as confirmed by spherical‐aberration‐corrected transmission electron microscopy and X‐ray absorption fine structure spectroscopy. For aerobic alcohol oxidation, Pd1/CeO2 shows extremely high catalytic activity with a TOF of 6739 h−1 and satisfactory selectivity (almost 100 % for benzaldehyde), while Pd6/CeO2 is inactive, indicating that the true active species are single Pd atoms. Theoretical simulations reveal that the bulkier Pd6 clusters hinder the interactions between hydroxy groups and the CeO2 surface, thus suppressing synergy of Pd‐Ce perimeter.
Propylene polymerization over supported Ziegler–Natta catalysts: Effect of internal and external donors on distribution of active sites according to stereospecificity
Authors: Nikolaeva Marina , Matsko Mikhail , Zakharov Vladimir 
Published: February 2018

ABSTRACTData on the content of fractions with different microtacticities for polypropylene (PP) samples produced over three catalysts [the “donor‐free” titanium–magnesium catalyst and catalysts with dibutyl phthalate and 1,3‐diether(fluorene) used as internal donors] upon polymerization in the absence/presence of an external donor (ED) have been obtained by preparative temperature rising elution fractionation method. The effect of internal and EDs on the distribution of PP fractions with different microtacticity is discussed. Data on molecular weight and thermophysical characteristics were obtained for individual fractions with different microtacticities. Correlations were found between microtacticity, molecular weight, and the melting points of these fractions. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46291.
Global biomass trade for energy— Part 2: Production and trade streams of wood pellets, liquid biofuels, charcoal, industrial roundwood and emerging energy biomass
Authors: Proskurina Svetlana , Junginger Martin , Heinimö Jussi , Tekinel Beysin , Vakkilainen Esa 
Published: February 2018

AbstractMany countries have limited low‐cost biomass resources to satisfy their own demand for bioenergy; consequently, international trade in biomass in various liquid and solid forms is increasing. The aim of this study is to present a quantitative overview of the development of international biomass trade for energy purposes. This paper focuses on the main biomass producing and consuming countries, as well as exporters and importers of liquid and solid biofuels, such as wood pellets, biodiesel, and bio‐ethanol, and biomass products, for example industrial roundwood. The study discusses changes in trends that have occurred over the past decade, and investigates emerging energy biomass trade streams. Due to increased demand for wood pellets from the heating and industrial sectors, global wood pellet markets and international trade have increased significantly in the past decade. The United States and Brazil remain leaders in bio‐ethanol production with about 45 Mt and 24 Mt respectively. In recent years, Asian markets such as China (industrial roundwood), South Korea (wood pellets), Malaysia, and Indonesia (palm oil) have developed considerably. In the EU‐28, more than 60% of total palm oil consumption is used for energy purposes. The EU is the global leader in biomass for energy utilization and also the main importer of most biomass products, particularly wood pellets. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd
Microalgae cultivation and metabolites production: a comprehensive review
Authors: Vuppaladadiyam Arun K. , Prinsen Pepijn , Raheem Abdul , Luque Rafael , Zhao Ming 
Published: February 2018

AbstractMicroalgae have important potential in the bio‐based industry. However, their light‐utilization mechanisms are still not fully understood. Together with knowledge of their metabolic pathways and their responses in carbon partitioning to different primary metabolites (carbohydrates, lipids and proteins), this information is essential if their potential and profitability are to be better exploited. The first part of this review describes the techniques used for microalgae cultivation and the growth factors that determine their productivity, one of the most important factors in techno‐economic assessment studies of microalgae production systems. In the second part, a closer look is taken at their chemical composition in relation to the biosynthesis of primary and secondary metabolites. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd
“Cooperative collapse” of the denatured state revealed through Clausius‐Clapeyron analysis of protein denaturation phase diagrams
Authors: Tischer Alexander , Machha Venkata R. , Rösgen Jörg , Auton Matthew 
Published: February 2018

AbstractProtein phase diagrams have a unique potential to identify the presence of additional thermodynamic states even when non‐2‐state character is not readily apparent from the experimental observables used to follow protein unfolding transitions. Two‐state analysis of the von Willebrand factor A3 domain has previously revealed a discrepancy in the calorimetric enthalpy obtained from thermal unfolding transitions as compared with Gibbs‐Helmholtz analysis of free energies obtained from the Linear Extrapolation Method (Tischer and Auton, Prot Sci 2013; 22(9):1147‐60). We resolve this thermodynamic conundrum using a Clausius‐Clapeyron analysis of the urea‐temperature phase diagram that defines how
and the urea m‐value interconvert through the slope of cm versus T,
. This relationship permits the calculation of
at low temperature from m‐values obtained through iso‐thermal urea denaturation and high temperature m‐values from
obtained through iso‐urea thermal denaturation. Application of this equation uncovers sigmoid transitions in both cooperativity parameters as temperature is increased. Such residual thermal cooperativity of
and the m‐value confirms the presence of an additional state which is verified to result from a cooperative phase transition between urea‐expanded and thermally‐compact denatured states. Comparison of the equilibria between expanded and compact denatured ensembles of disulfide‐intact and carboxyamidated A3 domains reveals that introducing a single disulfide crosslink does not affect the presence of the additional denatured state. It does, however, make a small thermodynamically favorable free energy (∼–13 ± 1 kJ/mol) contribution to the cooperative denatured state collapse transition as temperature is raised and urea concentration is lowered. The thermodynamics of this “cooperative collapse” of the denatured state retain significant compensations between the enthalpy and entropy contributions to the overall free energy.
Engineered CRISPR/Cas9 system for multiplex genome engineering of polyploid industrial yeast strains
Authors: Lian Jiazhang , Bao Zehua , Hu Sumeng , Zhao Huimin 
Published: February 2018

AbstractThe CRISPR/Cas9 system has been widely used for multiplex genome engineering of Saccharomyces cerevisiae. However, its application in manipulating industrial yeast strains is less successful, probably due to the genome complexity and low copy numbers of gRNA expression plasmids. Here we developed an efficient CRISPR/Cas9 system for industrial yeast strain engineering by using our previously engineered plasmids with increased copy numbers. Four genes in both a diploid strain (Ethanol Red, 8 alleles in total) and a triploid strain (ATCC 4124, 12 alleles in total) were knocked out in a single step with 100% efficiency. This system was used to construct xylose‐fermenting, lactate‐producing industrial yeast strains, in which ALD6, PHO13, LEU2, and URA3 were disrupted in a single step followed by the introduction of a xylose utilization pathway and a lactate biosynthetic pathway on auxotrophic marker plasmids. The optimized CRISPR/Cas9 system provides a powerful tool for the development of industrial yeast based microbial cell factories.
Enhancing cytochrome P450‐mediated non‐natural cyclopropanation by mutation of a conserved second‐shell residue
Authors: Gober Joshua G. , Rydeen Amy E. , Schwochert Timothy D. , Gibson‐O'Grady Evan J. , Brustad Eric M. 
Published: February 2018

AbstractEngineered cytochrome P450s are emerging as powerful synthetic tools due to their ability catalyze non‐native metallocarbenoid and ‐nitrenoid insertion reactions. P450‐mediated cyclopropanation has garnered particular interest due to the high selectivity demonstrated by engineered scaffolds and their application towards the synthesis of therapeutic agents. We previously reported that mutation of a conserved, first‐shell heme‐ligating Cys to Ser led to significant improvements in cyclopropanation activity in a model enzyme, P450BM3h. Here, we demonstrate that mutation of a ubiquitously conserved second‐shell Phe (F393) to His or Ala, provides complementary increases in the P450 heme reduction potential and conversion to cyclopropanation products when compared to first‐shell Cys to Ser mutations. Furthermore, we show that these mutations confer improved non‐natural catalysis in 4 diverse P450 scaffolds.