bluuebunny/crossref_metadata_2025 huggingface dataset:
Achieving a Record‐High Yield Rate of 120.9 for N2 Electrochemical Reduction over Ru Single‐Atom Catalysts
Authors: Geng Zhigang , Liu Yan , Kong Xiangdong , Li Pai , Li Kan , Liu Zhongyu , Du Junjie , Shu Miao , Si Rui , Zeng Jie
Published: August 2018

The electrochemical reduction of N2 into NH3 production under ambient conditions represents an attractive prospect for the fixation of N2. However, this process suffers from low yield rate of NH3 over reported electrocatalysts. In this work, a record‐high activity for N2 electrochemical reduction over Ru single atoms distributed on nitrogen‐doped carbon (Ru SAs/N‐C) is reported. At −0.2 V versus reversible hydrogen electrode, Ru SAs/N‐C achieves a Faradaic efficiency of 29.6% for NH3 production with partial current density of −0.13 mA cm−2. Notably, the yield rate of Ru SAs/N‐C reaches 120.9 , which is one order of magnitude higher than the highest value ever reported. This work not only develops a superior electrocatalyst for NH3 production, but also provides a guideline for the rational design of highly active and robust single‐atom catalysts.
Fast Exfoliation and Functionalisation of Two‐Dimensional Crystalline Carbon Nitride by Framework Charging
Authors: Jia Jingjing , White Edward R. , Clancy Adam J. , Rubio Noelia , Suter Theo , Miller Thomas S. , McColl Kit , McMillan Paul F. , Brázdová Veronika , Corà Furio , Howard Christopher A. , Law Robert V. , Mattevi Cecilia , Shaffer Milo S. P.
Published: August 2018

Two‐dimensional (2D) layered graphitic carbon nitride (gCN) nanosheets offer intriguing electronic and chemical properties. However, the exfoliation and functionalisation of gCN for specific applications remain challenging. We report a scalable one‐pot reductive method to produce solutions of single‐ and few‐layer 2D gCN nanosheets with excellent stability in a high mass yield (35 %) from polytriazine imide. High‐resolution imaging confirmed the intact crystalline structure and identified an AB stacking for gCN layers. The charge allows deliberate organic functionalisation of dissolved gCN, providing a general route to adjust their properties.
Butane‐1‐sulfonic acid immobilized on magnetic Fe3O4@SiO2 nanoparticles: A novel and heterogeneous catalyst for the one‐pot synthesis of barbituric acid and pyrano[2,3‐d] pyrimidine derivatives in aqueous media
Authors: Pourghasemi‐Lati M. , Shirini F. , Alinia‐Asli M. , Rezvani M.A.
Published: August 2018

Butane‐1‐sulfonic acid immobilized on magnetic Fe3O4@SiO2 nanoparticles (Fe3O4@SiO2‐Sultone) was easily prepared via direct ring opening of 1,4‐butanesultone with nanomagnetic Fe3O4@SiO2. The prepared reagent was characterized and used for the efficient promotion of the synthesis of barbituric acid and pyrano[2,3‐d] pyrimidine derivatives. All reactions were performed under mild and completely heterogeneous reaction conditions affording products in good to high yields. The catalyst is easily isolated from the reaction mixture by magnetic decantation and can be reused at least eight times without significant loss in activity.
Design and synthesis of two armed molecular receptor for recognition of Gd3+ metal ion and its computational study
Authors: Mohan Brij , Modi Krunal , Patel Chirag , Bhatia Pankaj , Kumar Ashwani , Sharma Harish Kumar
Published: August 2018

New receptor Phenylene‐Bis‐Methylfuran‐yl‐2‐Methyele Acetohydrazide (PBMMA) has been synthesized by condensation of hydrazide and 5‐methyl furfural. Synthesized receptor has been fully characterized by IR, 1H NMR, 13C NMR, mass spectroscopic and thermo gravimetric analysis. The receptor PBMMA shows selective recognition potential towards Gd3+ ion when tested with several metal ions such as Na+, K+, Mg2+, Cu2+, Cd2+, Hg2+, Y3+, La3+, Eu3+, Sm3+, Gd3+, Re6+ and Th4+ ion as their sulfates by UV–visible and fluorescence spectroscopic studies. Binding nature of PBMMA with Gd3+ ion was further studied by mass spectroscopic and cyclic voltammetric studies. The stoichiometry of PBMMA‐Gd3+ ion has been established, 1:1 by Benesi‐Hildebrand plot method and method of continuous variation (Job's plot) with association affinity K = 6.491 × 104 M−1. In addition to these, molecular docking, molecular dynamic stimulation and binding energy of complex; through Density Function theory −595.66 kcal/mol has also indication of strong binding. The electron transfer energy of Higher occupied molecular orbital (HOMO) to Lower unoccupied molecular orbital (LUMO) is about 4.186 eV and 295 nm for PBMMA‐Gd3+ Complex.
Calix[4]arenes functionalized dual‐imprinted mesoporous film for the simultaneous selective recovery of lithium and rubidium
Authors: Wang Yuanyuan , Xu Jicheng , Yang Dongya , Zhang Tao , Qiu Fengxian , Pan Jianming
Published: August 2018

Calixarenes have been drawing tremendous interest due to their special structure, superior properties and numerous applications. In this work, a novel adsorbent material, calix[4]arenes functionalized dual‐imprinted mesoporous film (DIMFs) for the simultaneous selective recovery of Li(I) and Rb(I), was prepared via surface ionic imprinting. Compared with ordinary adsorbent materials, the synthesis process of the films used a cheap bio‐template and did not require extra steps but significantly enhances adsorption properties. The morphology and structure of prepared DIMFs were characterized by scanning electron microscopy, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT‐IR) and nitrogen adsorption–desorption measurements. Adsorption parameters (pH and temperature), adsorption kinetics and adsorption isotherms of the DIMFs were investigated by adsorption experiments. This novel adsorbent has inorganic–organic hybrid frameworks, high specific surface area and uniform pore size. The Langmuir and Freundlich isotherms, pseudo‐first‐order and pseudo‐second‐order kinetics of DIMFs were investigated; suggesting that the adsorption data well fits the Langmuir isotherm model, and the adsorption kinetics can be described by the pseudo‐second‐order kinetic model. In addition, dual‐imprinted mesoporous film exhibited superior selectivity for Li(I) and Rb(I). Cycle test demonstrated an outstanding of reusability, which appreciating their potential for industrial application.
Transformative mobilities in the Pacific: Promoting adaptation and development in a changing climate
Authors: Farbotko Carol , McMichael Celia , Dun Olivia , Ransan‐Cooper Hedda , McNamara Karen E. , Thornton Fanny
Published: August 2018

Climate change is affecting Pacific life in significant and complex ways. Human mobility is shaped by climate change and is increasingly positioned by international agencies, policymakers, and governments as having an important role in both climate change adaptation and human development. We consider the potential for human mobility to promote adaptation and development among Pacific people in a changing climate. We argue that where Pacific people choose mobility, this should be supported and create opportunities that are responsive to the histories and existing patterns of mobility and place attachment among Pacific Islanders; commence from a position of climate and development justice; and advance human rights and socio‐political equity. Transformative mobilities are where mobility, adaptation, and development intersect to achieve the best possible outcomes for cultural identity, human rights, adaptation, and human development goals across scales and in origin and destination sites.
High‐Performance Magnetic Refrigerant Featuring One‐Dimensional Gd‐O Chains and O‐Gd3 Triangles
Authors: Tao Ce , Li Rukang
Published: August 2018

Magnetic cooling at low temperature has attracted intensive interest in cryogenics research, which may become important as cooling medium for long‐wave photon detectors to support space exploration. Here, we report a Gd‐based quaternary magnetic refrigerant material, Gd5BSi2O13, containing chains of face‐shared GdO9 polyhedra and geometrically frustrated OGd3 triangles. Magnetic measurements indicate that Gd5BSi2O13 exhibits a large magnetocaloric effect (MCE) about 1.74 times that of the practical magnetic refrigerant GGG (−ΔSm=67.0 J kg−1 K−1). We analyzed the origin of the large MCE by comparing GdIII‐containing compounds with different structures and concentrations of GdIII.
Most calbindin‐immunoreactive neurons, but few calretinin‐immunoreactive neurons, express the m1 acetylcholine receptor in the middle temporal visual area of the macaque monkey
Authors: Coppola Jennifer J. , Disney Anita A.
Published: August 2018

Introduction

Release of the neuromodulator acetylcholine into cortical circuits supports cognition, although its precise role and mechanisms of action are not well understood. Little is known about functional differences in cholinergic modulatory effects across cortical model systems, but anatomical evidence suggests that such differences likely exist because, for example, the expression of cholinergic receptors differs profoundly both within and between species.

Methods

In the primary visual cortex (V1) of macaque monkeys, cholinergic receptors are strongly expressed by inhibitory interneurons. Using dual‐immunofluorescence confocal microscopy, we examine m1 muscarinic acetylcholine receptor expression by two subclasses of inhibitory interneurons—identified by their expression of the calcium‐binding proteins calbindin and calretinin—in the middle temporal extrastriate area (MT) of the macaque.

Results and Conclusions

We find that the majority of calbindin‐immunoreactive neurons (55%) and only few calretinin‐immunoreactive neurons (10%) express the m1 acetylcholine receptor. These results differ from the pattern observed in V1 of the same species, lending further support to the notion that cholinergic modulation in the cortex is tuned such that different cortical compartments will respond to acetylcholine release in different ways.
Detecting peripersonal space: The promising role of ultrasonics
Authors: Chillura Antonino , Naro Antonino , Ciappina Fabrizio , Bramanti Alessia , Lauria Paola , Bramanti Placido , Calabrò Rocco Salvatore
Published: August 2018

Introduction

The approach of an external stimulus to the peripersonal space (PPS) modifies some physiological measures, including the cerebral blood flow (CBF) in the supplementary motor area and premotor cortex. CBF measurement may be useful to assess brain activations when producing specific motor responses, likely mediated by cortical and subcortical neural circuits.

Methods

This study investigated PPS in 15 healthy humans by characterizing the hemodynamic responses (pulsatility index, PI; and heart rate, HR) related to different directions of movements of individual's hand toward and backward his/her own face, so to perturb PPS).

Results

We observed that the CBF and HR were enhanced more when the stimulated hand was inside the PPS of the face in the passive and active condition than when the hand was outside the PPS and during motor imagery task.

Conclusions

These results suggest that the modulation of PPS‐related brain responses depends on specific sensory‐motor integration processes related to the location and the final position of a target in the PPS. We may thus propose TCD as a rapid and easy approach to get information concerning brain responses related to stimuli approaching the PPS. Understanding the modulations of brain activations during tasks targeting PPS can help to understand the results of psychophysical and behavioral trials and to plan patient‐tailored cognitive rehabilitative training.
Crystal Structure of PigA: A Prolyl Thioester‐Oxidizing Enzyme in Prodigiosin Biosynthesis
Authors: Lee Cheng‐Chung , Ko Tzu‐Ping , Chen Chun‐Ting , Chan Yueh‐Te , Lo Shin‐Yi , Chang Jen‐Yu , Chen Ya‐Wen , Chung Ting‐Fang , Hsieh Hsin‐Ju , Hsiao Chwan‐Deng , Wang Andrew H.‐J.
Published: August 2018

Prodigiosin is an intensely red pigment comprising three pyrroles. The biosynthetic pathway includes a two‐step proline oxidation catalyzed by phosphatidylinositol N‐acetylglucosaminyltransferase subunit A (PigA), with flavin adenine dinucleotide (FAD) as its cofactor. The enzyme is crystallized in the apo form and in complex with FAD and proline. As an acyl coenzyme A dehydrogenase (ACAD) family member, the protein folds into a β‐sheet flanked by two α‐helical domains. PigA forms a tetramer, which is consistent with analytical ultracentrifugation results. FAD binds to PigA in a similar way to that in the other enzymes of the ACAD family. The variable conformations of loop β4–β5 and helix αG correlate well with the structural flexibility required for substrate entrance to the Re side of FAD. Modeling with PigG, the acyl carrier protein, suggests a reasonable mode of interaction with PigA. The structure helps to explain the proline oxidation mechanism, in which Glu244 plays a central role by abstracting the substrate protons. It also reveals a plausible pocket for oxygen binding to the Si side of FAD.
The role of the long non‐coding RNA HOXA11‐AS in promoting proliferation and metastasis of malignant tumors
Authors: Lu Shounan , Jiang Xingming , Su Zhilei , Cui Zhankun , Fu Wen , Tai Sheng
Published: August 2018

Long non‐coding RNA (lncRNA) is one of the focuses and hotspots of biological research in recent years. At the same time, tumors have become the main disease that endangers human health. In recent years, a large number of researchers have explored the relationship between lncRNA and tumors. HOXA11‐AS is one of these lncRNAs. The long non‐coding RNA HOXA11 antisense RNA (HOXA11‐AS) is a novel lncRNA recently discovered. It is found in a variety of tumors such as ovarian cancer, glioma, and gastric cancer (GC) and so on, and is defined as an oncogene. It promotes tumor proliferation and metastasis by interacting with proteins such as miRNA and EZH2. In this paper, we review the mechanism of interaction between HOXA11‐AS and various tumors in recent years, and believe that it can be a potential tumor marker and therapeutic target in the future prevention and treatment of tumors.
miR‐185 affected the EMT, cell viability, and proliferation via DNMT1/MEG3 pathway in TGF‐β1‐induced renal fibrosis
Authors: Xue Rong , Li Yingping , Li Xiaoli , Ma Jingang , An Caiping , Ma Zhigang
Published: August 2018

Kidney fibrosis is usually the final manifestation of a wide variety of renal diseases. Recent years, research reported that long non‐coding RNAs (lncRNAs) played important roles in a variety of human diseases. However, the role and underlying mechanisms of lncRNAs in kidney fibrosis were complicated and largely unclear. In our study, we constructed the cell model of renal fibrosis in HK2 cells using transforming growth factor β1 (TGF‐β1) and found that lncRNA maternally expressed gene 3 (MEG3) was downregulated in TGF‐β1‐induced renal fibrosis. We then found that overexpressed MEG3 inhibited the TGF‐β1‐induced promotion of epithelial–mesenchymal transition, cell viability, and proliferation. Furthermore, we demonstrated that DNA methyltransferases 1 (DNMT1) regulated the MEG3 expression by altering the CpGs methylation level of MEG3 promoter in TGF‐β1‐induced renal fibrosis. In addition, we further revealed that miR‐185 could regulate the DNMT1 expression and thus, modulate the MEG3 in TGF‐β1‐induced renal fibrosis. Ultimately, our study illustrated that the modulation of the miR‐185/ DNMT1/ MEG3 pathway exerted important roles in TGF‐β1‐induced renal fibrosis. In summary, our finding displayed a novel regulatory mechanism for TGF‐β1‐induced renal fibrosis, which provided a new potential therapeutic target for renal fibrosis.
Facile Fabrication of Ultrasmall Copper Species Confined in Mesoporous Silica for Chemo‐Selective and Stable Hydrogenation Ethylene Carbonate Derived from CO2
Authors: Zhang Chanjuan , Wang Liguo , Liu Jiaju , Yang Yanmi , He Peng , Cao Yan , Chen Jiaqiang , Li Huiquan
Published: August 2018

The hydrogenation of ethylene carbonate to co‐produce commodity methanol and ethylene glycol has attracted growing interests due to the potential chemical utilization of CO2 in large scale. In this work, we report a novel and facile protocol for the preparation of mesoporous Cu@SiO2 catalysts and successfully applied the as‐synthesized catalysts in the hydrogenation of ethylene carbonate. The catalysts were characterized in detail by means of N2 physisorption, N2O titration, XRD, FT‐IR, H2‐TPR, TEM and XPS (XAES). This strategy is an effective method for fabricating the unique flower‐like mesoporous Cu@SiO2 with sub‐2.0 nm ultrasmall Cu particles. The results revealed that the involvement of β‐cyclodextrin improved the Cu dispersion and facilitated exposing more copper active sites, which also indicated that the confined catalyst inhibiting the sintering of copper particles. Meanwhile, the stability of the attained catalyst was superior with the modification of carbon. Importantly, among the catalysts tested in the hydrogenation of ethylene carbonate, 25Cu@SiO2‐β‐P with appropriate copper loading as well as moderate Cu+ ratio exhibited superior catalytic performance. Accordingly, the synergistic effect between the Cu+ and metallic Cu0 species was crucial for obtaining better catalytic activity.
Improved Design of the Lurgi Reactor for Methanol Synthesis Industry
Authors: Walid Belabbas Abou Bakr Tariq , Hassiba Benyounes , Boumediene Haddou , Weifeng Shen
Published: August 2018

Current studies are devoted to promote the production yield of the methanol synthesis process for treating large feed capacities in Algerian methanol manufacture industry by designing new reactor technologies. In order to achieve a high yield of methanol, the performance of methanol synthesis is improved by substituting the quench reactor by a new Lurgi reactor. The design of operating parameters of the Lurgi reactor involves the effect of CO2 injection on methanol production yield and the catalyst deactivation. The simulation results demonstrate that under the same industrial operating conditions the conversion rate of reactants increases from 23 % in the quench reactor to 37 % in the Lurgi reactor and the methanol yield can be increased by 33 % when substituting the quench reactor by the Lurgi reactor
Charge‐Transfer Salts of 6,6‐Dicyanopentafulvenes: From Topology to Charge Separation in Solution
Authors: Finke Aaron D. , Zalibera Michal , Confortin Daria , Kelterer Anne‐Marie , Mensing Christian , Haberland Sophie , Diederich François , Gescheidt Georg
Published: August 2018

6,6‐Dicyanopentafulvene derivatives and metallocenes with redox potentials appropriate for forming their radical anions form highly persistent donor–acceptor salts. The charge‐transfer salts of 2,3,4,5‐tetraphenyl‐6,6‐dicyanofulvene with cobaltocene (1⋅Cp2Co) and 2,3,4,5‐tetrakis(triisopropylsilyl)‐6,6‐dicyanofulvene with decamethylferrocene (2⋅Fc*) have been prepared. The X‐ray structures of the two salts, formed as black plates, were obtained and are discussed herein. Compared with neutral dicyanopentafulvenes, the chromophores in the metallocene salts show substantial changes in bond lengths and torsional angles in the solid state. EPR, NMR, and optical spectroscopy, as well as superconducting quantum interference device (SQUID) measurements, reveal that charge‐separation in the crystalline states and in frozen and fluid solutions depends on subtle differences of redox potentials, geometry, and on ion pairing. Whereas 1⋅Cp2Co reveals paramagnetic character in the crystalline state and in solution, compound 2⋅Fc* shows a delicate balance between para‐ and diamagnetism, depending on the temperature and solvent characteristics.
Ionic Donor–Acceptor Chain Derived from an Electron‐Transfer Reaction of a Paddlewheel‐Type Diruthenium(II, II) Complex and N,N′‐Dicyanoquinonediimine
Authors: Sekine Yoshihiro , Shimada Tomoka , Miyasaka Hitoshi
Published: August 2018

A new ionic donor–acceptor (D+A−) chain compound, [{Ru2(2,6‐(CF3)2PhCO2)2(p‐PhPhCO2)2}DMDCNQI] (1; 2,6‐(CF3)2PhCO2−=2,6‐bis(trifluoromethyl)benzoate; p‐PhPhCO2−=4‐biphenylcarboxylate; DMDCNQI=2,5‐dimethyl‐N,N′‐dicyanoquinonediimine) was isolated and structurally characterized. It represents the first of this type of ionic chain compounds.
Two Pairs of Chiral “Tower‐Like” Ln4Cr4 (Ln=Gd, Dy) Clusters: Syntheses, Structure, and Magnetocaloric Effect
Authors: Cui Chenhui , Cao Jia‐Peng , Luo Xi‐Ming , Lin Qing‐Fang , Xu Yan
Published: August 2018

Two pairs of novel chiral chromium lanthanide compounds, formulated as l‐ and d‐[Gd4Cr4(IN)10(μ3‐OH)4(μ4‐O)4(H2O)12]⋅[IN]2⋅8 H2O (1 and 3), and l‐ and d‐[Dy4Cr4(IN)11(μ3‐OH)4(μ4‐O)4(H2O)8]⋅[IN]⋅1.5 H2O (2 and 4) (HIN=isonicotinic acid) have been successfully synthesized and characterized. Structural analysis reveals that four Ln3+ ions and four Cr3+ ions connect with each other and yield a “tower‐like” [Ln4Cr4] skeleton. Apart from the above featuring an aesthetically charming structure, circular dichroism (CD) spectra confirm that compounds 1 and 3, 2 and 4 are enantiomers. To the best of our knowledge, these are the largest chiral chromium lanthanide compounds. In addition, magnetic interaction shows that Gd (the mixture of 1 and 3) exhibits significant cryogenic magnetocaloric effect (MCE) with −ΔSm=18.08 J kg−1 K−1(34.69 mJ cm−3 K−1). Also, the observed second‐harmonic generation efficiencies of [Gd4Cr4(IN)10(μ3‐OH)4(μ4‐O)4(H2O)12]⋅[IN]2⋅8 H2O and [Dy4Cr4(IN)11(μ3‐OH)4(μ4‐O)4(H2O)8]⋅[IN]⋅1.5 H2O are 0.3 and 0.4 times that of urea, respectively.
Yellow Emission from Low Coordination Site of Sr2SiO4:Eu2+, Ce3+: Influence of Lanthanide Dopants on the Electron Density and Crystallinity in Crystal Site Engineering Approach
Authors: Mani Rajaboopathi , Gupta Santosh Kumar , Ghosh Partha Sarathi , Jiang Huaidong
Published: August 2018

Lanthanide doping through a crystal site engineering approach tunes the emission wavelength suitable for LED applications, but weak emission from low coordination sites remains a huge challenge. Herein the use of a sensitizer is reported to enhance the emission strength and unravel the crystallinity and phase, as this approach demands a large amount of dopants. Doping of Eu2+ ions at SrO10 and SrO9 sites of Sr2SiO4 (S2S), respectively, tunes the emission from green to yellow and controlled doping of a Ce3+ sensitizer quadruples the quantum efficiency of yellow emission. Remarkably, doping of Eu2+ at the SrO9 site produces polycrystals, whereas co‐doping of Ce3+ and Eu2+ at the same site produces single crystals. DFT calculations further delineate the underlying changes wherein strong interaction of dopant with its neighbours determines the electron density, and thus the crystallinity and phase, rather than usual explanation of aliovalent conditions, which is further substantiated by TEM results. Irrespective of dopant valence, use of large amounts of dopants and their interaction with the host is responsible for the crystallinity and phase change (α′‐S2S to β‐S2S). The XPS valence band spectra experimentally evidences the changes in bonding nature of O 2p and O 2s orbitals of silicate and its electron density, due to doping at the two sites. In short, the outcomes resulting from this work could be extended for the development of other two‐coordination site lanthanide‐doped materials and crystallization of inorganic materials.
Mapping the Magnetic Anisotropy at the Atomic Scale in Dysprosium Single‐Molecule Magnets
Authors: Klahn Emil A. , Gao Chen , Gillon Beatrice , Gukasov Arsen , Fabrèges Xavier , Piltz Ross O. , Jiang Shang‐Da , Overgaard Jacob
Published: August 2018

The anisotropy of the magnetic properties of molecular magnets is a key descriptor in the search for improved magnets. Herein, it is shown how an analytical approach using single‐crystal polarized neutron diffraction (PND) provides direct access to atomic magnetic susceptibility tensors. The technique was applied for the first time to two Dy‐based single‐molecule magnets and showed clear axial atomic susceptibility for both DyIII ions. For the triclinic system, bulk magnetization methods are not symmetry‐restricted, and the experimental magnetic easy axes from both PND, angular‐resolved magnetometry (ARM), and theoretical approaches all match reasonably well. ARM curves simulated from the molecular susceptibility tensor determined with PND show strong resemblance with the experimental ones. For the monoclinic compound, comparison can only be made with the theoretically calculated magnetic anisotropy, and in this case PND yields an easy‐axis direction that matches that predicted by electrostatic methods. Importantly, this technique allows the determination of all elements of the magnetic susceptibility tensor and not just the easy‐axis direction, as is available from electrostatic predictions. Furthermore, it has the capacity to provide each of the anisotropic magnetic susceptibility tensors for all independent magnetic ions in a molecule and thus allows studies on polynuclear complexes and compounds of higher crystalline symmetry than triclinic.
Borabicyclo[3.2.0]heptadiene: A Fused Bicyclic Isomer of Borepin
Authors: Kelch Hauke , Kachel Stephanie , Wahler Johannes , Celik Mehmet Ali , Stoy Andreas , Krummenacher Ivo , Kramer Thomas , Radacki Krzysztof , Braunschweig Holger
Published: August 2018

A new isomer of borepin, identified as 2‐borabicyclo[3.2.0]hepta‐3,6‐diene by single‐crystal X‐ray diffraction and heteronuclear NMR spectroscopy, was obtained by reaction of 1‐mesityl‐2,3,4,5‐tetraphenylborole with the diaminoalkyne bis(piperidyl)acetylene. Analogous reactions of the alkyne with other borole derivatives generated seven‐membered borepins, in which a second equivalent of the alkyne was found to insert into the exocyclic B−C bond. Results of mechanistic DFT studies as well as differences in the reactivity of the boroles toward the diaminoalkyne are discussed.
X‐ray Constrained Spin‐Coupled Wavefunction: a New Tool to Extract Chemical Information from X‐ray Diffraction Data
Authors: Genoni Alessandro , Franchini Davide , Pieraccini Stefano , Sironi Maurizio
Published: August 2018

The X‐ray constrained wavefunction (XCW) approach is a reliable and widely used method of quantum crystallography that allows the determination of wavefunctions compatible with X‐ray diffraction data. So far, all the existing XCW techniques have been developed in the framework of molecular orbital theory and, consequently, provide only pictures of the “experimental” electronic structures that are far from the traditional chemical perception. Here a new strategy is proposed that, by combining the XCW philosophy with the spin‐coupled method of valence bond theory, enables direct extraction of traditional chemical information (e.g., weights of resonance structures) from X‐ray diffraction measurements. Preliminary results have shown that the new technique is really able to efficiently capture the effects of the crystal environment on the electronic structure, and can be considered as a new useful tool to perform chemically sound analyses of the X‐ray diffraction data.
CFD simulation of annular oil flow wrapped with water
Authors: Siqueira Fabio C. S. , Farias Irene S. , Moraes Júnior Deovaldo , dos S. Vianna Ardson
Published: August 2018

The transport of heavy oil in tubes is energy intensive since the oil viscosity can reach values of 10 500 000 cP. This study focuses on the transport of oil in a piping system by an annular flow of oil wrapped with water, since this alternative reduces head loss. The piping system was comprised of horizontal tubes, curves, and vertical tubes. The assumptions for the CFD simulation were the following: 3D geometry, turbulent flow, and isothermal system as well as incompressible, steady‐state, and transient flow. A mesh convergence study was carried out. The residue for pressure and velocity dropped at least three orders of magnitude. The inter‐phase‐slip Algorithm (IPSA), algebraic slip model (ASLP), scalar equation method (SEM), and Phoenics models were applied to calculate the interaction between the phases. Turbulence was modelled with default k‐ϵ and k‐ω models and the LES strategy by using a Smagorinsky sub‐grid scale model. The density profiles generated in the CFD simulation were compared with experimental data and a resemblance was observed. The transient simulation showed a swirling flow that was experimentally observed, which was a result of synergy of multiphase flow, horizontal tube, curve, and vertical tube.
Molecular Recognition of a Thomsen–Friedenreich Antigen Mimetic Targeting Human Galectin‐3
Authors: Santarsia Sabrina , Grosso Ana Sofia , Trovão Filipa , Jiménez‐Barbero Jesús , Carvalho Ana Luísa , Nativi Cristina , Marcelo Filipa
Published: August 2018

Overexpression of the Thomsen–Friedenreich (TF) antigen in cell membrane proteins occurs in 90 % of adenocarcinomas. Additionally, the binding of the TF antigen to human galectin‐3 (Gal‐3), also frequently overexpressed in malignancy, promotes cancer progression and metastasis. In this context, structures that interfere with this specific interaction have the potential to prevent cancer metastasis. A multidisciplinary approach combining the optimized synthesis of a TF antigen mimetic with NMR, X‐ray crystallography methods, and isothermal titration calorimetry assays was used to unravel the molecular structural details that govern the Gal‐3/TF mimetic interaction. The TF mimetic has a binding affinity for Gal‐3 similar to that of the TF natural antigen and retains the binding epitope and bioactive conformation observed for the native antigen. Furthermore, from a thermodynamic perspective, a decrease in the enthalpic contribution was observed for the Gal‐3/TF mimetic complex; however, this behavior is compensated by a favorable gain in entropy. From a structural perspective, these results establish our TF mimetic as a scaffold to design multivalent solutions to potentially interfere with Gal‐3 aberrant interactions and for likely use in hampering Gal‐3‐mediated cancer cell adhesion and metastasis.
An area‐efficient low‐power SCM topology for high performance network‐on Chip (NoC) architecture using an optimized routing design
Authors: Poovendran R. , Sumathi S.
Published: August 2018

The incorporation of network‐on‐Chip with communication delivers a strengthening solution to the rising complexity and problems in system‐on‐chip. Here, mesh topology is shortly connected, utilizing the symmetric properties of the network, and is introduced. In addition, 4x4‐Router Architecture–Carry Select Adder (4x4‐RA‐CSLA) method is proposed to improve the function of the Router Architecture (RA) in the network. These features make the system achieve efficient architecture in terms of lower area and power for the interconnection of network scenarios. This new architecture is debugged using ModelSim with Verilog code. The experimental result shows improvement in area and power.
Surrogate Endpoints in Pediatric Studies Submitted to the US FDA
Authors: Green Dionna J. , Sun Haihao , Burnham Janelle , Liu Xiaomei I. , van den Anker John , Temeck Jean , Yao Lynne , McCune Susan K. , Burckart Gilbert J.
Published: August 2018

The 21st Century Cures Act was passed in December, 2016, and included a number of provisions to facilitate drug approval. Considerable discussion was generated related to some aspects of the Act, especially to the use of surrogate endpoints (SEs) as a means to shorten the time required prior to receiving US Food and Drug Administration (FDA) approval.1 The objective of this analysis was to identify the use and outcomes of SEs and clinical endpoints in pediatric drug development trials.
Safety Threshold Considerations for Sunscreen Systemic Exposure: A Simulation Study
Authors: Wang Jian , Ganley Charles J.
Published: August 2018

Sunscreens are regulated as over‐the‐counter drugs in the United States. Some sunscreen ingredients are absorbed into the systemic circulation, which raises concerns about the safety of these drugs. There is limited information on the systemic exposure for most sunscreen ingredients. This report estimates the systemic absorption of two sunscreen active ingredients, oxybenzone and enzacamene, by developing a pharmacokinetic model from published sunscreen absorption data and compares the results with safety thresholds proposed by the US Food and Drug Administration and in the literature. Our analysis indicates that systemic absorption can be substantial, and evaluation of the systemic exposure of sunscreen ingredients is warranted to better assess any long‐term risks of use.
Free‐Sustaining Three‐Dimensional S235 Steel‐Based Porous Electrocatalyst for Highly Efficient and Durable Oxygen Evolution
Authors: Han Weijia , Kuepper Karsten , Hou Peilong , Akram Wajiha , Eickmeier Henning , Hardege Jörg , Steinhart Martin , Schäfer Helmut
Published: August 2018

A novel oxygen evolution reaction (OER) catalyst (3 D S235‐P steel) based on a steel S235 substrate was successfully prepared by facile one‐step surface modification. The standard carbon‐manganese steel was phosphorized superficially, which led to the formation of a unique 3 D interconnected nanoporous surface with a high specific area that facilitated the electrocatalytically initiated oxygen evolution reaction. The prepared 3 D S235‐P steel exhibited enhanced electrocatalytic OER activities in the alkaline regime, as confirmed by a low overpotential (326 mV at a 10 mA cm−2) and a small Tafel slope of 68.7 mV dec−1. Moreover, the catalyst was found to be stable under long‐term usage conditions, functioning as an oxygen‐evolving electrode at pH 13, as evidenced by the sufficient charge‐to‐oxygen conversion rate (faradaic efficiency: 82.11 and 88.34 % at 10 and 5 mA cm−2, respectively). In addition, it turned out that the chosen surface modification delivered steel S235 as an OER electrocatalyst that was stable under neutral pH conditions. Our investigation revealed that the high catalytic activities likely stemmed from the generated Fe/(Mn) hydroxide/oxohydroxides generated during the OER process. Phosphorization treatment therefore not only is an efficient way to optimize the electrocatalytic performance of standard carbon‐manganese steel but also enables for the development of low‐costing and abundant steels in the field of energy conversion.
Association of Interleukin‐1 beta and tumor necrosis factor‐alpha genetic polymorphisms with gastric cancer in India
Authors: Sultana Zareen , Bankura Biswabandhu , Pattanayak Arup Kumar , Sengupta Debmalya , Sengupta Mainak , Saha Makhan Lal , Panda Chinmay Kumar , Das Madhusudan
Published: August 2018

Interleukin 1 beta (IL‐1β) and Tumor necrosis factor alpha (TNF‐α) are key inflammatory cytokines whose polymorphisms have been correlated with increased susceptibility to gastric cancer (GC). Since geographical and racial differences exist in cancer rates, our study was aimed to evaluate the first possible association of polymorphisms in these genes with GC risk in West Bengal, India. Polymorphisms in IL‐1β and TNF‐α genes were genotyped in 120 GC patients and 135 healthy individuals. Combined effect of the SNPs in both genes with GC risk was determined through allele dosage analysis (ADA) and the survival data were analyzed by Log Rank Test. The study results revealed that IL‐1β rs1143627: T > C, rs16944: C > T (p = 0.001;OR = 1.85; 95% CI 1.30‐2.63) and rs1143633: G > A (p < 0.0001; OR = 2.53; 95% CI 1.67‐3.83) and TNF‐α rs1800630: C > A, rs1799964: T > C (p < 0.0001; OR = 2.31; 95% CI 1.54‐3.46) polymorphisms significantly contributed toward GC risk. Moreover, ADA showed that carriage of 7 “effective” risk alleles conferred a risk of almost 10‐fold in comparison to individuals carrying less than 3 “effective” risk alleles. Our survival analysis also indicated a significant association between IL‐1β rs1143627: T > C and rs16944: C > T and patient survivability. The presence of H. pylori enhanced the risk in individuals with IL‐1β rs1143627:CC and rs16944:TT genotypes. Further, meta‐analysis revealed significant association of IL‐1β rs1143627: T > C (p = 0.026; OR = 4.165; 95% CI 1.18‐14.65) and rs16944: C > T (p = 0.01; OR = 5.49; 95% CI 1.48‐20.37) in presence of H. pylori with gastric cancer in Asian population though no significant difference (p > 0.05) was found when compared to absence of H. pylori Environ. Mol. Mutagen. 59:653–667, 2018. © 2018 Wiley Periodicals, Inc.
Pompeji des Perms
Authors: Rößler Ronny , Luthardt Ludwig , Zierold Thorid
Published: August 2018

Der „Versteinerte Wald von Chemnitz“ ist eine etwa 291 Millionen Jahre alte paläobotanische Fossillagerstätte – und ein außergewöhnlich gut vulkanisch konserviertes Ökosystem. Geologen gewinnen hier Einblicke in das Werden und Vergehen von Lebensräumen und die Dynamiken von Umwelt‐ und Klimawandel.
Petrogenesis and metallogenic implications of Cretaceous magmatism in Central Lhasa, Tibetan Plateau: A case study from the Lunggar Fe skarn deposit and perspective review
Authors: Cao Hua‐Wen , Zhang Yun‐Hui , Santosh M. , Li Guang‐Ming , Hollis Steven P. , Zhang Lin‐Kui , Pei Qiu‐Ming , Tang Li , Duan Zhi‐Ming
Published: August 2018

The Lhasa terrane is one of the major segments of the Tibetan Plateau, with widespread Mesozoic to Cenozoic magmatic and metallogenic records. Here, we investigate timing and characteristics of magmatism associated with the Lunggar Fe skarn deposit in Central Lhasa. We also present Sr–Nd–Pb and Hf (zircon) isotopic data on three associated intrusions to gain insights on the tectonic and metallogenic evolution of the region. Our data reveal at least two magmatic pulses in Lunggar represented by Early Cretaceous I‐type granodiorite (112.9 ± 1.5 Ma) and granite porphyry (112.6 ± 1.3 Ma) with magma generation related to slab break‐off associated with the Bangong–Nujiang Ocean during closure of the Meso‐Tethyan ocean at ~113 Ma. Iron skarn mineralization at Lunggar was contemporaneous with local Early Cretaceous intrusive activity. Following this, Late Cretaceous adakitic diorite (90.5 ± 1.5 Ma) formed from delaminated thickened crust at ~91 Ma related to the northern subduction of the Yarlung‐Zangbo oceanic plate. We also provide a comprehensive review of the Cretaceous tectonic evolution of Central Lhasa, which trace the tectonic evolution as follows: (a) 145–120 Ma: southward subduction of the Bangong–Nujiang oceanic plate under the Lhasa terrane; (b) 120–115 Ma: Lhasa‐Qiangtang continental collision; (c) 115–110 Ma: slab break‐off of the Bangong–Nujiang Ocean; (d) 110–95 Ma: crustal thickening of the Central Lhasa lower crust; (e) 95–80 Ma: delamination of lithospheric mantle; and (f) 80–65 Ma: northward subduction of the Yarlung‐Zangbo oceanic plate and subsequent slab rollback. The related metallogenic events in Central Lhasa include (a) ~115–110 Ma skarn Fe mineralization associated with slab break‐off; (b) ~90–80 Ma porphyry Cu–Au mineralization formed in delaminated thickened crust of Central Lhasa; and (c) ~65 Ma skarn Pb–Zn mineralization produced from slab rollback of the Yarlung‐Zangbo Ocean.
Brainstem network disruption: A pathway to sudden unexplained death in epilepsy?
Authors: Mueller Susanne G. , Nei Maromi , Bateman Lisa M. , Knowlton Robert , Laxer Kenneth D. , Friedman Daniel , Devinsky Orrin , Goldman Alica M.
Published: August 2018

Observations in witnessed Sudden Unexpected Death in Epilepsy (SUDEP) suggest that a fatal breakdown of the central autonomic control could play a major role in SUDEP. A previous MR study found volume losses in the mesencephalon in focal epilepsy that were more severe and extended into the lower brainstem in two patients who later died of SUDEP. The aims of this study were to demonstrate an association (1) between brainstem volume loss and impaired autonomic control (reduced heart rate variability [HRV]); (2) between brainstem damage and time to SUDEP in patients who later died of SUDEP. Two populations were studied: (1) Autonomic system function population (ASF, 18 patients with focal epilepsy, 11 controls) with HRV measurements and standardized 3 T MR exams. (2) SUDEP population (26 SUDEP epilepsy patients) with clinical MRI 1–10 years before SUDEP. Deformation‐based morphometry of the brainstem was used to generate profile similarity maps from the resulting Jacobian determinant maps that were further characterized by graph analysis to identify regions with excessive expansion indicating significant volume loss or atrophy. The total number of regions with excessive expansion in ASF was negatively correlated with HRV (r = −.37, p = .03), excessive volume loss in periaqueductal gray/medulla oblongata autonomic nuclei explained most of the HRV associated variation (r/r2 = −.82/.67, p < .001). The total number of regions with excessive expansion in SUDEP was negatively correlated with time to SUDEP (r = −.39, p = .03), excessive volume loss in the raphe/medulla oblongata at the obex level explained most of the variation of the time between MRI to SUDEP (r/r2 = −.60/.35,p = .001). Epilepsy is associated with brainstem atrophy that impairs autonomic control and can increase the risk for SUDEP if it expands into the mesencephalon.
Pillar[5]arene‐stabilized Plasmonic Nanoparticles as Selective SERS Sensors
Authors: Montes‐García Verónica , Rodal‐Cedeira Sergio , Cordero‐Ferradás María José , Gómez Borja , García‐Río Luis , Pastoriza‐Santos Isabel , Pérez‐Juste Jorge
Published: August 2018

We present here a simple procedure for the surface modification of plasmonic nanoparticles (NPs) with a cationic water‐soluble ammonium pillar[5]arene (AP[5]A) in order to create selective surface‐enhanced Raman scattering (SERS) spectroscopy based sensors. The strategy is based on a ligand exchange reaction between the AP[5]A and the stabilizing agent of the as‐prepared plasmonic NPs. The approach could be applied to plasmonic nanoparticles either negatively charged, stabilized by citrate ions (Au spheres) or positively charged, stabilized by cetyltrimethylammonium bromide (Au and Au@Ag nanorods). The SERS performance of all systems was studied as a function of NP size and excitation laser line by using an analyte with no affinity towards the metal surface such as pyrene. The analytical enhancement factor (AEF) for the different systems was estimated between 0.55×104 and 1.49×105. Finally the synergistic effect of combining supramolecular chemistry and plasmonic NPs is demonstrated through SERS‐based detection, in aqueous media, of molecules with no affinity towards a bare plasmonic substrate such as the contaminant pyrene or the biomolecule pyocyanin with nanomolar limit of detection.
Currency risk premia: Perceptions of downside risk and deviations from benchmark values
Authors: Furnagiev Steven , Stillwagon Joshua
Published: August 2018

This paper examines the empirical performance of an alternative model of the currency risk premium. This model relates risk not to the variance of returns but rather to potential crash risk based on the deviation, or “gap,” between the exchange rate and perceptions of its benchmark value. The model is tested using a novel data set of traders' exchange rate forecasts, from 1986:08 to 2013:09. The forecast data eliminate the need for a joint hypothesis about expectations formation through direct measurement of the market's ex ante premium. To measure the benchmark value, rather than use purchasing power parity, we relate it to recent levels through a moving average. Strong support is found for the prediction that the premium comoves positively with the “gap” measure of risk, according to cointegrated vector autoregression analyses for all four markets examined. This result is robust for moving averages from six to 24 months and when controlling for exchange rate volatility. The findings suggesthowinvestors assess downside risk ex ante, at least in part, and may rationalize the application of certain technical analysis.
Graphene quantum dot‐enhanced chemiluminescence through energy and electron transfer for the sensitive detection of tyrosine
Authors: Pang Chunhua , Han Suqin , Li Yue , Zhang Junmei
Published: August 2018

Graphene quantum dots (GQD) could significantly enhance the chemiluminescence (CL) reaction of Ce(IV) with NaHSO3 through energy and electron transfer. The chemiluminescence resonance energy transfer (CRET) occurred between SO2*/1O2 and GQD, and radiative electron–hole annihilation came from the combining of the hole‐injected GQD (GQD•+) and electron‐injected GQD (GQD•–). Tyrosine (Tyr) is easily oxidized by OH• and Ce(IV), which results in the decrease of OH• and Ce(IV), and the CL intensity of the GQD–Ce(IV)–NaHSO3 system is inhibited by Tyr. In this way, the GQD‐based CL as a sensitive and selective method was applied for the detection of Tyr in the range 0.02–8.00 μM with the detection limit of 4.0 nM. The method was applied to the determination of Tyr in food samples with satisfactory results.
YAP and TAZ, the conductors that orchestrate eye development, homeostasis, and disease
Authors: Zhu Jing‐Yi , Lin Sen , Ye Jian
Published: August 2018

Yes‐associated protein (YAP) and transcriptional coactivator with PDZ‐binding motif (TAZ) are transcriptional coactivators established as a nexus in numerous signaling pathways, notably in Hippo signaling. Previous research revealed multifarious function of YAP and TAZ in oncology and cardiovasology. Recently, the focus has been laid on their pivotal role in eye morphogenesis and homeostasis. In this review, we synthesize advances of YAP and TAZ function during eye development in different model organisms, introduce their function in different ocular tissues and eye diseases, and highlight the potential for therapeutic interventions.
Optimal cut‐off value of fecal calprotectin for the evaluation of ulcerative colitis: An unsolved issue?
Authors: Jha Ashish Kumar , Chaudhary Madhur , Dayal Vishwa Mohan , Kumar Amarendra , Jha Sanjeev Kumar , Jha Praveen , Purkayastha Shubham , Ranjan Ravish
Published: August 2018

Introduction

There is variability in the fecal calprotectin (FCP) cut‐off level for the prediction of ulcerative colitis (UC) disease activity and differentiation from irritable bowel disease (IBS‐D). The FCP cut‐off levels vary from country to country.

Aims

We aimed to assess FCP as a marker of disease activity in patients with UC. We determined the optimal FCP cut‐off value for differentiating UC and IBS‐D.

Methods

In a prospective study, we enrolled 76 UC and 30 IBS‐D patients. We studied the correlation of FCP with disease activity/extent as well as its role in differentiating UC from IBS‐D. We also reviewed literature regarding the optimal FCP cut‐off level for the prediction of disease activity and differentiation from IBS‐D patients.

Results

Sensitivity, specificity, positive predictive value, and negative predictive value of FCP (cut‐off level, 158 μg/g) for the prediction of complete mucosal healing (using Mayo endoscopic subscore) were 90, 85, 94.7, and 73.3%, respectively. Sensitivity, specificity, positive predictive value, and negative predictive value of FCP (cut‐off level, 425 μg/g) for the prediction of inactive disease (Mayo Score ≤ 2) were 94.3, 88.7, 86.2, and 95.4%, respectively. We also found a FCP cut‐off value of 188 μg/g for the differentiation of UC from IBS‐D.

Conclusions

The study reveals the large quantitative differences in FCP cut‐off levels in different study populations. This study demonstrates a wide variation in FCP cut‐off levels in the initial diagnosis of UC as well as in follow‐up post‐treatment. Therefore, this test requires validation of the available test kits and finding of appropriate cut‐off levels for different study populations.