bluuebunny/crossref_metadata_2025 huggingface dataset:
Bisanthracene‐Based Donor–Acceptor‐type Light‐Emitting Dopants: Highly Efficient Deep‐Blue Emission in Organic Light‐Emitting Devices
Authors: Hu Jian‐Yong , Pu Yong‐Jin , Satoh Fumiya , Kawata So , Katagiri Hiroshi , Sasabe Hisahiro , Kido Junji
Published: December 2013

Deep‐blue fluorescent compounds are particularly important in organic light‐emitting devices (OLEDs). A donor–accepotor (DA)‐type blue‐emitting compound, 1‐(10‐(4‐methoxyphenyl)anthracen‐9‐yl)‐4‐(10‐(4‐cyanophenyl)anthracen‐9‐yl)benzene (BD3), is synthesized, and for comparison, a nonDA‐type compound, 1,4‐bis(10‐phenylanthracene‐9‐yl)benzene (BD1) and a weak DA‐type compound, 1‐(10‐phenylanthracen‐9‐yl)‐4‐(10‐(4‐cyanophenyl)anthracen‐9‐yl)‐benzene (BD2), are also synthesized. The twisted conformations of the two anthracene units in the compounds, confirmed by single crystal X‐ray analysis, effectively prevent π‐conjugation, and the compound shows deep‐blue photoluminescence (PL) with a high PL quantum efficiency, almost independent of the solvent polarity, resulting from the absence of an intramolecular charge transfer state. The DA‐type molecule BD3 in a non‐doped device exhibits a maximum external quantum efficiency (EQE) of 4.2% with a slight roll‐off, indicating good charge balance due to the DA‐type molecular design. In the doped device with 4,4′‐bis(N‐carbazolyl)‐1,1′‐biphenyl (CBP) host, the BD3 exhibits higher EQE than 10% with Commission International de L'Eclairge (CIE) coordinates of (0.15, 0.06) and a narrow full‐width at half‐maximum of 45 nm, which is close to the CIE of the high definition television standard blue.
Highly Luminescent ZnO Quantum Dots Made in a Nonthermal Plasma
Authors: Felbier Patrick , Yang Jihua , Theis Jens , Liptak Richard William , Wagner Andrew , Lorke Axel , Bacher Gerd , Kortshagen Uwe
Published: December 2013

Nonthermal plasmas allow the preparation of ligand‐free quantum dots combining high production rates with superior crystalline quality and luminescence properties. Here, ZnO quantum dots are produced in a radiofrequency capacitively‐coupled plasma, exhibiting size dependent photoluminescent quantum yields up to 60% after air exposure—the highest reported to date for any compound semiconductor quantum dots prepared in the gas phase. Systematic studies indicate the importance of the surface for the observed luminescence behavior. The high luminescent quantum yields in the visible range of the spectrum and the ligand‐free, scalable synthesis make these quantum dots good candidates for light emitting applications.
Modular Synthesis of Triarylmethanes through Palladium‐Catalyzed Sequential Arylation of Methyl Phenyl Sulfone
Authors: Nambo Masakazu , Crudden Cathleen M.
Published: December 2013

Triarylmethanes, which are valuable structures in materials, sensing and pharmaceuticals, have been synthesized starting from methyl phenyl sulfone as an inexpensive and readily available template. The three aryl groups were installed through two sequential palladium‐catalyzed CH arylation reactions, followed by an arylative desulfonation. This method provides a new synthetic approach to multisubstituted triarylmethanes using readily available haloarenes and aryl boronic acids, and is also valuable for the preparation of unexplored triarylmethane‐based materials and pharmaceuticals.
Die photoredoxkatalysierte Meerwein‐Addition: intermolekulare Aminoarylierung von Alkenen
Authors: Prasad Hari Durga , Hering Thea , König Burkhard
Published: December 2013

Eine Vielzahl von Amiden ist unter milden Bedingungen durch intermolekulare Aminoarylierung unter Verwendung einer photokatalytischen Meerwein‐Addition mit sichtbarem Licht erhältlich. Das Syntheseprotokoll erlaubt einen breiten Substratbereich, toleriert eine Bandbreite von funktionellen Gruppen und wurde auf die Synthese eines Isochinolidalkaloids angewendet.
Direct Spectroscopic Detection of the Orientation of Free OH Groups in Methyl Lactate–(Water)1,2 Clusters: Hydration of a Chiral Hydroxy Ester
Authors: Thomas Javix , Sukhorukov Oleksandr , Jäger Wolfgang , Xu Yunjie
Published: December 2013

Hydration of chiral molecules is a subject of significant current interest in light of recent experimental observations of chirality transfer from chiral solutes to water in solution and the important roles which water plays in biological events. Using a broadband chirped pulse and a cavity based microwave spectrometer, we detected spectroscopic signatures of the mono‐ and dihydrates of methyl lactate, a chiral hydroxy ester. Surprisingly, these small hydration clusters show highly specific binding preferences. Not only do they strongly prefer the insertion H‐bonding topology, but they also favor specific pointing direction(s) for their non‐H‐bonded hydroxy group(s). We observed that the particular dihydrate conformer identified is not the most stable one predicted. This work highlights the superior capability of high‐resolution spectroscopy to identify specific water binding topologies, and provides quantitative data to test state‐of‐the‐art theory.
Multicomponent Synthesis of Unsymmetrical Unsaturated N‐Heterocyclic Carbene Precursors and Their Related Transition‐Metal Complexes
Authors: Queval Pierre , Jahier Claire , Rouen Mathieu , Artur Isabelle , Legeay Jean‐Christophe , Falivene Laura , Toupet Loic , Crévisy Christophe , Cavallo Luigi , Baslé Olivier , Mauduit Marc
Published: December 2013

A low‐cost, modular, and easily scalable multicomponent procedure affording access in good yields and excellent selectivity (up to 93 %) to a wide range of (a)chiral unsymmetrical 1‐aryl‐3‐cycloalkyl‐imidazolium salts is disclosed. Electronic and steric properties of the corresponding unsymmetrical unsaturated N‐heterocyclic carbene (U2‐NHC) ligands were evaluated and evidenced strong electron donor ability, high steric discrimination, and modular steric demand.
Sequence Control in Polymer Chemistry through the Passerini Three‐Component Reaction
Authors: Solleder Susanne C. , Meier Michael A. R.
Published: December 2013

A new strategy to achieve sequence control in polymer chemistry based on the iterative application of the versatile Passerini three‐component reaction (P‐3CR) in combination with efficient thiol–ene addition reactions is introduced. First, stearic acid was used as a starting substrate to build up a sequence‐defined tetramer with a molecular weight of 1.6 kDa. Using an acid‐functionalized PEG allowed for an easier isolation of the sequence‐defined macromolecules by simple precipitation and led to a sequence‐defined pentamer in a block‐copolymer architecture. Importantly, this new strategy completely avoids protecting group chemistry. By following this strategy, a different side chain can be introduced to the polymer/oligomer backbone in a simple way and at a defined position within the macromolecule.
Preparation and Characterization of high‐strength poly(ether ether ketone) films
Authors: Li Wenlei , Wang Guibin , Jiang Zhenhua , Liu Chuan , Huo Pengfei , Zhang Shuling
Published: December 2013

High‐strength poly(ether ether ketone) (PEEK) films were prepared through melt extrusion followed by stretching. The tensile strength, orientation, and crystallization behaviors of PEEK films were characterized by universal testing machine, thermomechanical analysis, wide‐angle X‐ray diffraction, and differential scanning calorimetry. The results indicated that the tensile strength of PEEK films mainly depended on the stretching rate (ν), stretching temperature (T), and stretching ratio (λL). Moreover, the tensile strength of the stretched PEEK film (333 MPa) was almost four times higher than that of the unstretched PEEK film (87 MPa) under an optimized condition. This is attributed to a synergistic effect of orientation and crystallization in the stretching process, and the influence of orientation is stronger than that of the crystallization on the improvement of the tensile strength of PEEK films. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40172.
Quantifying morphological and genetic variation of sympatric populations to guide conservation of endangered, micro‐endemic springsnails
Authors: Morningstar Cayla R. , Inoue Kentaro , Sei Makiri , Lang Brian K. , Berg David J.
Published: December 2013

The endangered snails Juturnia kosteri and Pyrgulopsis roswellensis are endemic to springs on Bitter Lake National Wildlife Refuge, NM, USA. These species are small and difficult to distinguish by shell shape.

A morphological analysis of these two species was conducted using geometric morphometrics, and a phylogenetic analysis using the mitochondrial DNA genes COI and ND1 was performed.

Principal component analysis showed significant overlap in shell shape between the two species. Phylogenetic analysis showed that the two species formed monophyletic clades, with each containing low genetic diversity. Analysis of molecular variance for each species showed significant variation among populations. Both species showed significant isolation‐by‐distance, but only P. roswellensis showed a significant relationship between shell shape and geographic distance.

The overlapping ranges and the similarity in shell morphology suggest that these micro‐endemic species are difficult to distinguish in the field, particularly by non‐specialists. This presents challenges to population management of these species.

Divergence among populations within each species indicates isolation at very small geographic scales. Because these desert springs are home to endemic species within a variety of invertebrate groups, they are likely to contain significant amounts of yet‐to‐be‐discovered biodiversity; many of these unknown taxa are also likely to be of conservation concern.

Copyright © 2013 John Wiley & Sons, Ltd.
Urantide Conformation and Interaction with the Urotensin‐II Receptor
Authors: Brancaccio Diego , Limatola Antonio , Campiglia Pietro , Gomez‐Monterrey Isabel , Novellino Ettore , Grieco Paolo , Carotenuto Alfonso
Published: December 2013

Urotensin II (U‐II) is a disulfide bridged peptide hormone identified as the ligand of a G protein‐coupled receptor. Human U‐II (H‐Glu‐Thr‐Pro‐Asp‐c[Cys‐Phe‐Trp‐Lys‐Tyr‐Cys]‐Val‐OH) has been described as the most potent vasoconstrictor compound identified to date. We have previously identified the compound termed urantide (H‐Asp‐c[Pen‐Phe‐DTrp‐Orn‐Tyr‐Cys]‐Val‐OH), which is the most potent UT receptor (UTR) antagonist described to date. Urantide may have potential clinical value in the treatment of atherosclerosis. In the present study, we studied the conformational preferences of urantide in DPC micelles and developed a urantide/UTR interaction model. This model can help the design of novel peptides and small molecules as UTR antagonists.
Steroidomimetic Aminomethyl Spiroacetals as Novel Inhibitors of the Enzyme Δ8,7‐Sterol Isomerase in Cholesterol Biosynthesis
Authors: Krojer Melanie , Müller Christoph , Bracher Franz
Published: December 2013

Grundmann's ketone is converted to a spiroacetal containing a 5‐hydroxymethyl‐5‐nitro‐1,3‐dioxane moiety whose hydroxymethyl group can be esterified or directly substituted with primary and secondary amines. Among the resulting aminomethyl spiroacetals, several ones bearing diamino residues were found to be inhibitors of the enzyme Δ8,7‐isomerase in cholesterol biosynthesis. The complex bicyclic building block derived from Grundmann's ketone could be replaced by a properly substituted tetraline scaffold, without noteworthy loss in activity. This opens the opportunity to perform further structural modifications for the design of new steroidomimetic inhibitors of human Δ8,7‐isomerase.
Developing a service robot for a children's library: A design‐based research approach
Authors: Lin Weijane , Yueh Hsiu‐Ping , Wu Hsin‐Ying , Fu Li‐Chen
Published: December 2013

Understanding book‐locating behavior in libraries is important and leads to more effective services that support patrons throughout the book‐locating process. This study adopted a design‐based approach to incorporate robotic assistance in investigating the book‐locating behaviors of child patrons, and developed a service robot for child patrons in library settings. We describe the iterative cycles and process to develop a robot to assist with locating resources in libraries. Stakeholders, including child patrons and librarians, were consulted about their needs, preferences, and performance in locating library resources with robotic assistance. Their needs were analyzed and incorporated into the design of the library robot to provide comprehensive support. The results of the study suggest that the library robot was effective as a mobile and humanoid service agent for providing motivation and knowledgeable guidance to help child patrons in the initially complicated sequence of locating resources.
Maternal genetic polymorphisms of phase II metabolic enzymes and the risk of fetal neural tube defects
Authors: Wang Linlin , Jin Lei , Liu Jufen , Zhang Yali , Yuan Yue , Yi Deqing , Ren Aiguo
Published: December 2013

Background

Maternal exposure to polycyclic aromatic hydrocarbons (PAHs) has been associated with the risk of fetal neural tube defects (NTDs). Whether maternal genetic variants related to PAH metabolism contribute to the development of fetal NTDs remains unclear.

Methods

We conducted a case–control study in a Chinese population to examine the association of selected maternal genetic variants of phase II enzymes involved in the elimination of the metabolic intermediates of these chemicals with fetal NTD risk, and to evaluate possible interaction of the genetic variant and maternal exposure to indoor air pollution from coal combustion and smoking (IAPCC). Blood samples were collected from 534 NTD case mothers and 534 control mothers and assayed for 12 polymorphisms of 5 genes encoding phase II enzymes.

Results

We found that the rs9282861 GG genotype of SULT1A1 was associated with an elevated risk of total NTDs (odds ratio [OR] = 2.12, 95% confidence interval [CI]: 1.49–3.00), compared with the GA genotype. The SULT1A1 rs9282861 variant showed a significant additive interaction with maternal exposure to IAPCC for NTD risk, with a relative excess risk of interaction of 1.20 (95% CI 0.23–2.18), and the OR for the joint effect of high‐level IAPCC exposure and the GG genotype was 8.37 (95% CI: 3.63–19.28).

Conclusion

Maternal SULT1A1 polymorphism is associated with the risk of fetal NTDs, and has an additive‐scale interaction with maternal IAPCC exposure for NTD risk. Birth Defects Research (Part A) 100:13–21, 2014. © 2013 Wiley Periodicals, Inc.
Validation of congenital anomaly coding in Canada's administrative databases compared with a congenital anomaly registry
Authors: Metcalfe Amy , Sibbald Barbara , Lowry R. Brian , Tough Suzanne , Bernier Francois P.
Published: December 2013

Background

Congenital anomaly (CA) surveillance provides epidemiologic data that are necessary for health planning. Approaches to CA surveillance vary; however, an increasing number of jurisdictions rely on administrative health databases for case ascertainment. This study aimed to assess the validity of CA coding in three administrative databases compared with a CA registry.

Methods

A cohort of 5862 live and stillborn infants from Calgary Alberta Canada was created through linking 12 clinical and administrative databases. Diagnostic codes for all health care contacts (hospitalizations, emergency room visits, out‐patient physician visits) in the first 3 months of life were examined for relevant International Classification of Disease codes. Sensitivity, positive predictive values, and kappa coefficients were calculated, and data from the Alberta Congenital Anomalies Surveillance System was used as the reference standard.

Results

The ability of administrative data to accurately ascertain CAs varied by data source and the specificity of the diagnosis. Consistently, hospitalization data out‐performed other administrative data sources in terms of sensitivity, positive predictive values, and kappa. Kappa scores for CAs easily visible at birth ranged from moderate (0.62 for emergency room visits and 0.65 for out‐patient physician claims) to good (0.83 for hospitalization data) depending on the data source.

Conclusion

The validity of CA coding in administrative databases compared with a CA registry varies by database used and by CA studied. This has important implications for national surveillance efforts. Condition‐specific validity should be assessed locally before use of these data sources for research or planning purposes. Birth Defects Research (Part A) 100:59–66, 2014. © 2013 Wiley Periodicals, Inc.
Transcriptional regulation improves the throughput of three‐hybrid counter selections in Saccharomyces cerevisiae
Authors: Harton Marie D. , Wingler Laura M. , Cornish Virginia W.
Published: December 2013

The yeast three‐hybrid (Y3H) assay expands the fields of drug discovery and protein engineering by enabling the search of large variant libraries for targets that do not inherently produce a distinct, measurable phenotype. The Y3H assay links the DNA‐binding and activation domains of a transcription factor via a chemically synthesized heterodimeric small molecule, thereby activating a downstream reporter gene. Although the Y3H assay has been successfully applied as a positive selection to discover novel drug targets and to evolve proteins with improved functions, its expansion into applications requiring a high‐throughput, versatile selection against transcriptional activation has been hindered by its limited dynamic range as a counter selection. Here, we describe the development of a second‐generation Y3H counter selection that uses the dual tetracycline (Tet) system to tighten transcriptional regulation of the reporter gene. The Tet Y3H counter selection has an improved dynamic range and provides enrichment from mock libraries of up to 106, a 104‐fold improvement over our original Y3H counter selection. This enhanced dynamic range brings the Y3H counter selection to a standard that is suitable for real‐world protein engineering applications.
Sustainable Development and the Consumer: Exploring the Role of Carbon Labelling in Retail Supply Chains
Authors: Hornibrook Sue , May Claire , Fearne Andrew
Published: December 2013

This empirical article contributes to the sustainable development debate by examining consumer responses to carbon labels within a real world context. Given the limitations of methodologies that use self‐reported or intended measures of purchasing behaviour, we use the loyalty card data of the largest supermarket retailer in the UK to measure the impact of carbon labels on sales by different consumer segments. The data show that the trial of carbon labels on supermarket own brand products has had no discernible impact on shifting demand to lower carbon products. In order to explore possible reasons for lack of impact, nine focus groups were held using purposive sampling by retailer consumer segments to allow an exploration of awareness, understanding and use of carbon labels. The findings from the focus groups identified possible reasons for this lack of impact: lack of awareness and understanding of carbon labelling; constraining or facilitating social and cultural influences; and the heterogeneous nature of consumers. As a result, a number of implications for stakeholders are discussed. Copyright © 2013 John Wiley & Sons, Ltd and ERP Environment.
The Role of Corporate Sustainability in a Low‐Cost Business Model – A Case Study in the Scandinavian Fashion Industry
Authors: Lueg Rainer , Pedersen Maria Medelby , Clemmensen Søren Nørregaard
Published: December 2013

This multi‐level case study illustrates how corporate sustainability contributes to the low‐cost business model of a Scandinavian fashion company.

Contrary to parts of the extant literature, we do not find that corporate sustainability directly adds measurable value (e.g. a better brand image); neither does it exert coercive control over critical supplier relationships. However, corporate sustainability minimizes the downside risk of the business model. It does so by (1) creating implicit contracts that reach beyond traditional ‘shareholder value’, (2) transferring risk to suppliers and (3) improving leadership by motivating management and employees, and by directing their attention to critical issues.

For companies, we offer the insight that corporate sustainability is a necessary complement to shareholder value, even if the relationship is not obvious at first sight. We also suggest that concerted actions of companies or a positive connotation of certification create effective control over suppliers. As to public policy, we conclude that regulators could introduce mandatory disclosure of suppliers to facilitate controls through stakeholders, or alternatively an industry‐wide comply‐or‐explain code of conduct. We also address how regulators can take direct actions against countries with unsustainable labor policies. Last, we suggest future research topics, e.g. expanding the notion of a business model by interpreting ‘adding value’ as prevention of losses. Copyright © 2013 John Wiley & Sons, Ltd and ERP Environment.
Being ‘Green and Competitive’: The Impact of Environmental Actions and Collaborations on Firm Performance
Authors: Dangelico Rosa Maria , Pontrandolfo Pierpaolo
Published: December 2013

In this paper, we seek to enhance the understanding of the link between environmental management and firm performance, so contributing to the debate of being “green and competitive”. Relying on the resource‐based view, we study the effect of different environmental management capabilities on a firm's market and image performance. In particular, we analyze the capabilities to implement product and process‐related environmental actions with different types of environmental focus (materials, energy, pollution) and the capabilities to develop environmental collaborations with different types of actors (both business actors and non‐business actors). To this aim we conducted a survey on 122 Italian companies. Results show that market performance and image performance have partially different antecedents. Specifically, a firm's market performance is positively affected by the capabilities to implement environmental actions with a focus on energy and pollution and to develop environmental collaborations both with business and with non‐business actors. On the other hand, a firm's image performance is positively affected by the capabilities to implement environmental actions with a focus on materials and to develop environmental collaborations with non‐business actors. Copyright © 2013 John Wiley & Sons, Ltd and ERP Environment
The Effect of Nitrogen on the Autoreduction of Cobalt Nanoparticles Supported on Nitrogen‐Doped Ordered Mesoporous Carbon for the Fischer–Tropsch Synthesis
Authors: Yang Yifei , Jia Litao , Hou Bo , Li Debao , Wang Jungang , Sun Yuhan
Published: December 2013

Nitrogen‐doped ordered mesoporous carbons (OMCs) were prepared by using a post‐synthetic method with cyanamide as a nitrogen source; they were used as supports for the fabrication of the cobalt‐based Fischer–Tropsch synthesis (FTS) catalysts. The obtained composites were well characterised by using nitrogen physisorption, Raman spectroscopy, high‐angle annular dark‐field scanning transmission electron microscopy, hydrogen chemisorption, X‐photoelectron spectroscopy, thermogravimetry–MS, and in situ XRD to investigate the effects of nitrogen on the dispersion of cobalt species and successive autoreduction behaviour of cobalt oxide as well as the catalytic performance in the FTS. The results indicate that the doped nitrogen atoms, especially the pyridine‐like nitrogen, actually serve as the anchoring sites for cobalt species. Consequently, the more uniform cobalt particle size is observed for the catalysts with nitrogen‐doped OMCs as supports in comparison with their counterparts based on the pristine OMCs. In contrast, the autoreduction temperature of cobalt oxide in the as‐synthesised catalysts lowers considerably after nitrogen doping, although slightly increased autoreduction temperature is observed for the catalysts with relatively high nitrogen content owing to the metal–support interaction. Dictated by the balance between decreasing particle size of cobalt and increasing strength of the metal–support interaction, the cobalt specific activity of the nitrogen‐doped catalysts reaches a maximum and then decreases in the FTS with increasing nitrogen content. Notably, under optimum conditions, the cobalt specific activity on the nitrogen‐doped sample with medium nitrogen content is 1.5 times higher than its analogue on the pristine OMC without compromising the selectivity to C5+ hydrocarbons.
Effect of the Counterion on Light Emission: A Displacement Strategy to Change the Emission Behaviour from Aggregation‐Caused Quenching to Aggregation‐Induced Emission and to Construct Sensitive Fluorescent Sensors for Hg2+ Detection
Authors: Zhao Na , Lam Jacky W. Y. , Sung Herman H. Y. , Su Hui Min , Williams Ian D. , Wong Kam Sing , Tang Ben Zhong
Published: December 2013

In this paper, a simple strategy to change the emission behaviour of luminogenic materials was developed. Tetraphenylethene (TPE)‐functionalised benzothiazolium salts with different counteranions (TPEBeX; X=I−, ClO4− and PF6−) were designed and synthesised. All the luminogens show weak red emission in the solution state that originates from intramolecular charge transfer from TPE to the benzothiazolium unit. Whereas aggregate formation enhances the light emission of TPEBeClO4 and TPEBePF6, that of TPEBeI is quenched, thus demonstrating the phenomena of aggregation‐induced emission and aggregation‐caused quenching. TPEBeI works as a light‐up fluorescent sensor for Hg2+ in aqueous solution with high sensitivity and specificity owing to the elimination of the emission quenching effect of the iodide ion by the formation of HgI2 as well as the induction in aggregate formation by the complexation of Hg2+ with the S atom of the benzothiazolium unit of TPEBeI. A solid film of TPEBeI was prepared that can monitor the level of Hg2+ in aqueous solution with a detection limit of 1 μM.
Nitrogen‐Doped Porous Graphitic Carbon as an Excellent Electrode Material for Advanced Supercapacitors
Authors: Sun Li , Tian Chungui , Fu Yu , Yang Ying , Yin Jie , Wang Lei , Fu Honggang
Published: December 2013

An advanced supercapacitor material based on nitrogen‐doped porous graphitic carbon (NPGC) with high a surface area was synthesized by means of a simple coordination–pyrolysis combination process, in which tetraethyl orthosilicate (TEOS), nickel nitrate, and glucose were adopted as porogent, graphitic catalyst precursor, and carbon source, respectively. In addition, melamine was selected as a nitrogen source owing to its nitrogen‐enriched structure and the strong interaction between the amine groups and the glucose unit. A low‐temperature treatment resulted in the formation of a NPGC precursor by combination of the catalytic precursor, hydrolyzed TEOS, and the melamine–glucose unit. Following pyrolysis and removal of the catalyst and porogent, the NPGC material showed excellent electrical conductivity owing to its high crystallinity, a large Brunauer–Emmett–Teller surface area (SBET=1027 m2 g−1), and a high nitrogen level (7.72 wt %). The unusual microstructure of NPGC materials could provide electrochemical energy storage. The NPGC material, without the need for any conductive additives, showed excellent capacitive behavior (293 F g−1 at 1 A g−1), long‐term cycling stability, and high coulombic efficiency (>99.9 % over 5000 cycles) in KOH when used as an electrode. Notably, in a two‐electrode symmetric supercapacitor, NPGC energy densities as high as 8.1 and 47.5 Wh kg−1, at a high power density (10.5 kW kg−1), were achieved in 6 M KOH and 1 M Et4NBF4‐PC electrolytes, respectively. Thus, the synthesized NPGC material could be a highly promising electrode material for advanced supercapacitors and other conversion devices.
α,β‐Unsaturated Acyl Cyanides as New Bis‐Electrophiles for Enantioselective Organocatalyzed Formal [3+3]Spiroannulation
Authors: Goudedranche Sébastien , Bugaut Xavier , Constantieux Thierry , Bonne Damien , Rodriguez Jean
Published: December 2013

α,β‐Unsaturated acyl cyanides are key bis‐electrophile substrates for successful domino enantioselective organocatalyzed Michael‐intramolecular acylation domino sequences. This new reactivity has been applied to the synthesis of enantioenriched azaspiro[4,5]decanone ring systems by a formal [3+3]spiroannulation, constituting a rare example of synthesis of glutarimides in an optically active form.
Physiological Stratification in Electricity‐Producing Biofilms of Geobacter sulfurreducens
Authors: Schrott Germán David , Ordoñez María Victoria , Robuschi Luciana , Busalmen Juan Pablo
Published: December 2013

The elucidation of mechanisms and limitations in electrode respiration by electroactive biofilms is significant for the development of rapidly emerging clean energy production and wastewater treatment technologies. In Geobacter sulfurreducens biofilms, the controlling steps in current production are thought to be the metabolic activity of cells, but still remain to be determined. By quantifying the DNA, RNA, and protein content during the long‐term growth of biofilms on polarized graphite electrodes, we show in this work that current production becomes independent of DNA accumulation immediately after a maximal current is achieved. Indeed, the mean respiratory rate of biofilms rapidly decreases after this point, which indicates the progressive accumulation of cells that do not contribute to current production or contribute to a negligible extent. These results support the occurrence of physiological stratification within biofilms as a consequence of respiratory limitations imposed by limited biofilm conductivity.
Electron‐Ion Relaxation, Phase Transitions, and Surface Nano‐Structuring Produced by Ultrashort Laser Pulses in Metals
Authors: Inogamov N. A. , Zhakhovsky V. V. , Petrov Yu. V. , Khokhlov V.A. , Ashitkov S. I. , Khishchenko K. V. , Migdal K. P. , Ilnitsky D. K. , Emirov Yu. N. , Komarov P. S. , Shepelev V. V. , Miller C.W. , Oleynik I.I. , Agranat M.B. , Andriyash A.V. , Anisimov S.I. , Fortov V.E.
Published: December 2013

Fundamental physical phenomena in metals irradiated by ultrashort laser pulses with absorbed fluences higher than few tens of mJ/cm2 are investigated. For those fluences, laser‐produced electron distribution function relaxes to equilibrium Fermi distribution with electron temperature Te within a short time of 10‐100 fs. Because the electron subsystem has Te highly exceeding much the ion subsystem temperature Ti the well‐known twotemperature hydrodynamic model (2T‐HD) is used to evaluate heat propagation associated with hot conductive electron diffusion and electron‐ion energy exchange. The model coefficients of electron heat conductivity κ (ϱ, Te, Ti) and electron‐ion coupling parameter α (ϱ, Te) together with 2T equation of state E (ϱ, Te, Ti) and P (ϱ, Te, Ti) are calculated.

Modeling with 2T‐HD code shows transition of electron heat wave from supersonic to subsonic regime of prop‐agation. At the moment of transition the heat wave emits a compression wave moving into the bulk of met al. Nonlinear evolution of the compression wave after its separation from the subsonic heat wave till spallation of rear‐side layer of a film is traced in both 2T‐HD modeling and molecular dynamics (MD) simulation.

For fluences above some threshold the nucleation of voids in frontal surface layer is initiated by strong tensile wave following the compression wave. If the absorbed fluence is ∼30 % above the ablation threshold than void nucleation develops quickly to heavily foam the molten met al. Long‐term evolution of the metal foam including foam breaking and freezing is simulated. It is shown that surface nano‐structures observed in experiments are produced by very fast cooling of surface molten layer followed by recrystallization of supercooled liquid in disintegrating foam having complex geometry. Characteristic lengths of such surface nanostructures, including frozen pikes and bubbles, are of the order of thickness of molten layer formed right after laser irradiation. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electrons in the Field of Interfering Laser Pulses with Tilted Fronts: Formation of Compressed Bunches and Their Application for the Generation of Coherent γ – Rays
Authors: Korobkin V.V. , Romanovskiy M.Yu. , Shiryaev O.B. , Trofimov V.A.
Published: December 2013

Simulations show that optical traps for charged particles can be formed in the fields of intense ultrashort laser pulses with tilted amplitude fronts. The traps travel in space with the velocities close to the speed of light and can be used for the creation of electron bunches which, at the laser intensities which are currently attainable, are compressed to proportions far below the laser wavelength and have energies reaching hundreds of GeV per particle. If an additional ultrashort laser pulse is propagated in the direction opposite to that of the bunch motion and interacts with the electrons, inverse Compton scattering occurs, with most of the electron energy being transferred to the resulting gamma‐quanta. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The safety of dipeptidyl peptidase‐4 (DPP‐4) inhibitors or sodium‐glucose cotransporter 2 (SGLT‐2) inhibitors added to metformin background therapy in patients with type 2 diabetes mellitus: a systematic review and meta‐analysis
Authors: Kawalec Paweł , Mikrut Alicja , Łopuch Sylwia
Published: December 2013

The aim of the present meta‐analysis was to assess the safety profile of dipeptidyl peptidase‐4 (DPP‐4) inhibitors and sodium‐glucose cotransporter 2 (SGLT‐2) inhibitors in comparison with placebo as add‐on to metformin therapy in patients with type 2 diabetes. Randomized controlled trials and controlled clinical trials were identified by searching Pubmed, Embase and the Cochrane Central Register of Controlled Trials database until 15 July 2013. All included studies were critically appraised and analysed with the use of Review Manager 5.1.0 software according to the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses statement protocol. Twenty randomized and double‐blinded studies published in 22 articles fulfilled the inclusion criteria for meta‐analysis. The overall results demonstrated that the use of oral antidiabetic agents (analysed separately and together) was not associated with any significantly increased risk of any serious adverse events including hypoglycaemia and gastrointestinal disorders. Moreover, the use of DPP‐4 or SGLT‐2 inhibitors significantly decreased risk of diarrhoea compared with placebo, when given concomitantly with metformin. However, we found that the SGLT‐2 inhibitors were more likely to cause a genital infection. Despite some limitations, the findings of this meta‐analysis indicate that DPP‐4 or SGLT‐2 inhibitors have favourable safety profile, and such therapy, when combined with metformin is well tolerated. Copyright © 2013 John Wiley & Sons, Ltd.
Incretins: Their physiology and application in the treatment of diabetes mellitus
Authors: Tasyurek Hale M. , Altunbas Hasan Ali , Balci Mustafa Kemal , Sanlioglu Salih
Published: December 2013

Therapies targeting the action of incretin hormones have been under close scrutiny in recent years. The incretin effect has been defined as postprandial enhancement of insulin secretion by gut‐derived factors. Likewise, incretin mimetics and incretin effect amplifiers are the two different incretin‐based treatment strategies developed for the treatment of diabetes. Although, incretin mimetics produce effects very similar to those of natural incretin hormones, incretin effect amplifiers act by inhibiting dipeptidyl peptidase‐4 (DPP‐4) enzyme to increase plasma concentration of incretins and their biologic effects. Because glucagon‐like peptide‐1 (GLP‐1) is an incretin hormone with various anti‐diabetic actions including stimulation of glucose‐induced insulin secretion, inhibition of glucagon secretion, hepatic glucose production and gastric emptying, it has been evaluated as a novel therapeutic agent for the treatment of type 2 diabetes mellitus (T2DM). GLP‐1 also manifests trophic effects on pancreas such as pancreatic beta cell growth and differentiation. Because DPP‐4 is the enzyme responsible for the inactivation of GLP‐1, DPP‐4 inhibition represents another potential strategy to increase plasma concentration of GLP‐1 to enhance the incretin effect. Thus, anti‐diabetic properties of these two classes of drugs have stimulated substantial clinical interest in the potential of incretin‐based therapeutic agents as a means to control glucose homeostasis in T2DM patients. Despite this fact, clinical use of GLP‐1 mimetics and DPP‐4 inhibitors have raised substantial concerns owing to possible side effects of the treatments involving increased risk for pancreatitis, and C‐cell adenoma/carcinoma. Thus, controversial issues in incretin‐based therapies under development are reviewed and discussed in this manuscript. Copyright © 2013 John Wiley & Sons, Ltd.
Sesquiterpenes from Artemisia argyi: Absolute Configurations and Biological Activities
Authors: Wang Shu , Sun Jian , Zeng Kewu , Chen Xiaoguang , Zhou Wanqi , Zhang Chen , Jin Hongwei , Jiang Yong , Tu Pengfei
Published: December 2013

Nine guaiane‐type sesquiterpenes and one eudesmane‐type one – namely argyinolides A–J (1–10) – as well as nine known analogues were isolated from the leaves of Artemisia argyi Levl. et Vant. Their structures were determined by interpretation of spectroscopic data (MS, 1D and 2D NMR). A combination of X‐ray crystal diffraction, specific optical rotations, CD spectroscopy, ECD calculation, and Mosher ester methods was employed to resolve the absolute configurations of the isolated compounds. Biological investigations into their cytotoxicities and anti‐inflammatory effects showed that 1, 13, 16, and 18 were remarkably cytotoxic against Bel‐742 and/or A549 cells, with IC50 values of 3.3–6.0 μM, whereas 7, 11–13, 16, and 18 exhibited sound inhibitory activity on LPS‐stimulated NO production in BV‐2 microglial cells, with IC50 values ranging from 3.2 to 8.6 μM. In addition, a brief discussion on the applicability of Geissman's rule for the sesquiterpene lactones, the probable reason for the presence of chlorine‐containing sesquiterpenes, and preliminary structure–activity relationships (SARs) are included.
Synthesis of Pladienolide B and Its 7‐Epimer with Insights into the Role of the Allylic Acetate
Authors: Müller Sarah , Sasse Florenz , Maier Martin E.
Published: December 2013

Diastereomeric macrolactones 41 and 48, which are epimeric at C‐7, were both prepared by a synthesis based on our previously developed route to the macrolactone core of pladienolide B. Both compounds contain all the functionality of the macrolactone core plus the vinyl iodide unit in the side chain. The key step to construct the seco acid for the macrolactonization was a Horner–Wadsworth–Emmons (HWE) reaction to produce acyclic enone 17. The required keto phosphonate for the HWE reaction was originally obtained from (R)‐(–)‐linalool. The derived macrolactone underwent a reduction of the enone function to give 7‐epi‐alcohol 20, and its acetylation, either under Mitsunobu or classical acylation conditions, produced allylic acetate 40. This represents a rare case in which a Mitsunobu reaction occurred with retention of configuration. The complete side chain that contains all the functionality was attached by a Stille cross‐coupling reaction to lead to 7‐epi‐pladienolide B (42). To obtain pladienolide B (1), the reduction of acyclic enone 17 under chelation‐controlled conditions [Zn(BH4)2, Et2O] gave allylic alcohol 43 with the correct configuration at C‐7 with regard to the natural product. Conversion of this allylic alcohol to seco acid 46 followed by a Shiina macrolactonization afforded vinyl iodide 48. Its Stille coupling with vinylstannane 39 provided pladienolide B (1). Preliminary testing for cytotoxicity against the L929 cell line showed 7‐epi‐pladienolide B (42) to be completely inactive, which is in contrast to pladienolide B (1) that displayed an IC50 (half maximal inhibitory concentration) value of 7.5 nM. These results point to the importance of the correct configuration of the OAc functional group at C‐7 of pladienolide B.
Toward improved drought tolerance in bioenergy crops: QTL for carbon isotope composition and stomatal conductance in Populus
Authors: Viger Maud , Rodriguez‐Acosta Maricela , Rae Anne M. , Morison James I. L. , Taylor Gail
Published: December 2013

Dedicated non‐food bioenergy crops like poplar are needed as sustainable, low‐input feedstocks for renewable energy in a future drier climate, where they can be grown on marginal soils. Such plants should have a low water, carbon, and chemical footprint. Capturing natural variation in traits associated with water use efficiency (WUE) is the first step to developing trees that require less water and may be adapted to drier environments. We have assessed stomatal conductance (gs) and leaf carbon isotope composition (δ13C, an indirect indicator of leaf WUE) in two Populus species, P. deltoides and P. trichocarpa and their F2 progeny, grown in the United Kingdom and in Italy. Populus deltoides leaves showed lower δ13C than P. trichocarpa, suggesting a higher WUE in P. trichocarpa, although without drought preconditioning, gs of P. trichocarpa was less responsive to dehydration and abscisic acid treatment than P. deltoides, suggesting that leaf anatomy may also contribute to δ13C in Populus. Quantitative trait loci (QTL) were identified for δ13C on eight linkage groups (LG) and two QTL for gs. From these. QTL and differential gene expression in response to drought from microarray data, we focused on three hotspots and identified 23 novel candidate genes on LG VI, X, and XVI. We have begun to unravel the genetic basis of WUE in bioenergy Populus revealing important underpinning data for breeding and improvement in poplar genotypes for a future drier climate.
Preparation and evaluation of PEO‐coated materials for a microchannel hemodialyzer
Authors: Heintz Keely , Schilke Karl F. , Snider Joshua , Lee Woo‐Kul , Truong Mitchell , Coblyn Matthew , Jovanovic Goran , McGuire Joseph
Published: December 2013

The marked increase in surface‐to‐volume ratio associated with microscale devices for hemodialysis leads to problems with hemocompatibility and blood flow distribution that are more challenging to manage than those encountered at the conventional scale. In this work stable surface modifications with pendant polyethylene oxide (PEO) chains were produced on polydimethylsiloxane (PDMS), polycarbonate microchannel, and polyacrylonitrile membrane materials used in construction of microchannel hemodialyzer test articles. PEO layers were prepared by radiolytic grafting of PEO‐polybutadiene‐PEO (PEO‐PB‐PEO) triblock polymers to the material surfaces. Protein repulsion was evaluated by measurement of surface‐bound enzyme activity following contact of uncoated and PEO‐coated surfaces with β‐galactosidase. Protein adsorption was decreased on PEO‐coated polycarbonate and PDMS materials to about 20% of the level recorded on the uncoated materials. Neither the triblocks nor the irradiation process was observed to have any effect on protein interaction with the polyacrylonitrile membrane, or its permeability to urea. This approach holds promise as a means for in situ application of safe, efficacious coatings to microfluidic devices for blood processing that will ensure good hemocompatibility and blood flow distribution, with no adverse effects on mass transfer. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 1014–1020, 2014.
Down‐Regulation of miR‐96 by Bone Morphogenetic Protein Signaling is Critical for Vascular Smooth Muscle Cell Phenotype Modulation
Authors: Kim Sunghwan , Hata Akiko , Kang Hara
Published: December 2013

The bone morphogenetic protein (BMP) signaling pathway is critical for the induction and maintenance of contractile phenotype in vascular smooth muscle cells (VSMCs). Inactivation of BMP signaling is common in abnormalities in vascular development and in vascular proliferative conditions, such as pulmonary artery hypertension. Herein, we identify microRNA‐96 (miR‐96) as a modulator of the VSMC phenotype in response to BMP4 signaling. We show that miR‐96 is down‐regulated by BMP4 treatment, which results in the derepression of a novel target, Tribbles‐like protein 3 (Trb3). miR‐96 targets a partially complementary sequence localized in the 3′ UTR of Trb3. Trb3 is an essential positive regulator of the BMP signaling pathway and promotes contractile phenotype in VSMCs. In conclusion, our study demonstrates a novel mechanism of regulation of SMC‐specific gene expression and induction of a VSMC contractile phenotype by the BMP4 signaling pathway via suppression of the miR‐96‐Trb3 axis. J. Cell. Biochem. 115: 889–895, 2014. © 2013 Wiley Periodicals, Inc.
Reactions of 4,5‐Dihydro‐1,4‐Benzothiazepin‐3(2H)‐one 1,1‐Dioxide and 1,5‐Dihydro‐4,1‐Benzothiazepin‐2(3H)‐one 4,4‐Dioxide Derivatives with Vilsmeier Reagent and DMFDMA
Authors: Tarasiuk Taras M. , Volovnenko Tatyana A. , Popov Kirill S. , Medviediev Volodymyr V. , Shishkin Oleg V. , Volovenko Yulian M.
Published: December 2013

The regioselectivity of the interaction between isomeric 4,5‐dihydro‐1,4‐benzothiazepin‐3(2H)‐one 1,1‐dioxide and 1,5‐dihydro‐4,1‐benzothiazepin‐2(3H)‐one 4,4‐dioxide derivatives with the Vilsmeier reagent and DMFDMA (N,N‐dimethylformamide dimethylacetal) has been investigated. The structures of synthesized compounds are confirmed by 1H, 13C NMR, elemental analysis, and X‐ray data.
Heavy metals in agricultural landscapes as hazards to human and ecosystem health: a case study on zinc and cadmium in drainage channel sediments
Authors: Savic Radovan , Ondrasek Gabrijel , Josimov‐Dundjerski Jasmina
Published: December 2013

BACKGROUND

In agricultural systems, heavy metals pose severe risks to the health of soil–plant–animal–human continuum. Drainage channels, as integral components of agricultural landscapes, contain sediment material that can be both a source and a sink of metals and other toxic/persistent elements due to its highly reactive interfaces and strong binding affinity. The drainage channel network in a case study area of Vojvodina (Serbia) is not appropriately protected from contamination, nor is it maintained regularly (e.g. by desilting), thus endangering and potentially decreasing the ecological value of surrounding water and agricultural land resources, i.e. exposing food production to potential contaminants. In this study (2004–2012), Cd and Zn concentrations were analysed in 100 samples from 46 drainage channels sediments spread along the areas of the most intensive agricultural land use in Vojvodina.

RESULTS

Among the samples measured, 5% had Cd and 14% had Zn concentrations above the maximally permitted levels, indicating that some drainage channel sections have been exposed to different point and non‐point source pollutants. The maximum detected concentrations of the analysed elements were >50% (Zn) and were as much as 11‐fold (Cd) higher than their remediation values.

CONCLUSION

There is a strong need for the establishment of qualitative monitoring of channel sediment media in agro‐ecosystems closely linked with complex pollution sources (intensive agriculture, industry, urban zones). © 2013 Society of Chemical Industry
Trudinger‐Moser inequalities on the entire Heisenberg group
Authors: Yang Yunyan
Published: December 2013

Continuing our previous work (Cohn, Lam, Lu, Yang, Nonlinear Analysis, 2011), we obtain a class of Trudinger‐Moser inequalities on the entire Heisenberg group, which indicate what the best constants are. All the existing proofs of similar inequalities on unbounded domain of the Euclidean space or the Heisenberg group are based on rearrangement argument. In this note, we propose a new approach to solve this problem. Specifically we get the global Trudinger‐Moser inequality by gluing local estimates with the help of cut‐off functions. Our method still works for similar problems when the Heisenberg group is replaced by the Euclidean space or complete noncompact Riemannian manifolds.