bluuebunny/crossref_metadata_2025 huggingface dataset:
High Performance Electrocatalyst Based on MIL‐101(Cr)/Reduced Graphene Oxide Composite: Facile Synthesis and Electrochemical Detections
Authors: Gu Jianxia , Yin Xiangdang , Bo Xiangjie , Guo Liping
Published: July 2018

In this work, a Cr‐based MOF (MIL‐101(Cr))/reduced grapheme oxide(rGO) electrocatalyst was prepared through a one‐pot hydrothermal method. The obtained composite was characterized via scanning electron microscopy, transmission electron microscopy, X‐ray diffraction and other standard techniques. Electrochemical methods were adopted to study the electrocatalytic ability of the composite. The results imply that, compared to the single components, it exhibits higher electrocatalytic activity for the reduction of metronidazole and stripping of Cd2+ and Pb2+. Optimizing the ratio of MIL‐101(Cr) and rGO, an electrochemical sensor was prepared using MIL‐101(Cr)/rGO‐20 and used for detection of metronidazole, Cd2+ and Pb2+, respectively. The linear range for metronidazole can be divided in two parts, i. e. from 0.5 to 200 μM and from 200 to 900 μM. The limit of detection is 0.24 μM (S/N=3, n=10). Likewise, it also exhibits a wide linear range from 0.05 to 6.0 μM for the detection of Cd2+ and Pb2+. The corresponding detection limits are found to be 5.2 nM and 3.0 nM (S/N=3, n=10), respectively. The proposed sensor also possesses superb selectivity, reproducibility, stability and can be applied to detect real samples with desired recovery rates. In addition, the possible reduction mechanism of metronidazole and adsorption mechanism of Cd2+ and Pb2+ were further discussed simply in this work.
3D‐1D Heterostructure of CoZn Oxyphosphide Nanosheets Anchored on Carbon Nanotubes as Electrocatalysts for the Oxygen Evolution Reaction
Authors: Xu Hui , Zhang Ke , Liu Chaofan , Tian Lin , Du Yukou
Published: July 2018

Realizing high‐efficiency electrochemical transformation of water is of paramount significance in the field of energy storage and conversion but still a major challenge. Herein, we successfully design and fabricate a class of 3D‐1D heterostructure of 3D CoZn oxyphosphide nanosheet assemblies anchored on 1D carbon nanotubes through a facile one‐pot method. Interestingly, owing to the doping of phosphorus atoms, modified electronic structures, as well as high surface areas, the well‐designed 3D‐1D CoZnP/CNTs nanohybrids exhibit excellent electrocatalytic performances toward oxygen evolution reaction, which needs an overpotential of only 281 mV to achieve a current density of 10 mA cm−2 and exhibits no evidences for activity degradation for 24 h, holding great potentials for acting as highly efficient electrocatalysts for the oxygen evolution reaction. This work may offer new options for constructing promising nanocatalysts with well‐defined heterostructure for water splitting and beyond.
High Ionic Conductor Member of Garnet‐Type Oxide Li6.5La3Zr1.5Ta0.5O12
Authors: Kataoka Kunimitsu , Akimoto Junji
Published: July 2018

Single‐crystal rods of Li6.5La3Zr1.5Ta0.5O12 were grown by floating zone melting. The typical size of the single‐crystal rod was 8 mm in diameter and 70 mm in length. Li6.5La3Zr1.5Ta0.5O12 crystallizes in a cubic structure with an Ia‐3d space group and the lattice parameter a=12.9455 (6) Å. The crystal structure of Li6.5La3Zr1.5Ta0.5O12 was refined to the conventional values of R=3.32 % and wR=4.45 % using single‐crystal X‐ray diffraction data, and to R=8.82 % and wR=7.45 % using single‐crystal neutron diffraction data. Li‐ions in the crystal structure occupied two crystallographic sites: the distorted tetrahedral 96 h site and the distorted octahedral 96 h site. Analyzing the results of AC impedance measurements, we estimated the total Li‐ion conductivity of member in Li6.5La3Zr1.5Ta0.5O12 to be 1.27×10−3 S cm−1 at 298 K. This value is the highest in the reported Li6.5La3Zr1.5Ta0.5O12 members. Using NMR spectroscopy, we determined the Li diffusion coefficient to be 1.57×10−13 m2 s−1 at 298 K and 7.96×10−13 m2 s−1 at 333 K. These values related to Li‐ion migration are higher than those reported for polycrystalline samples.
Optically Functionalized Grid‐Type Complexes by a Post‐Assembly Strategy
Authors: Eggers Berend , Ziener Ulrich
Published: July 2018

Bisterpyridine‐based grid complexes can serve as supramolecular three‐dimensional scaffolds for the construction of larger molecular assemblies. Through functionalization of the ligand with azide groups, followed by self‐assembly and metal‐free Huisgen reactions, eight pyrene molecules can be attached to the grid structure in a single reaction step. The orientation and proximity provided by the scaffold allows for tuning the fluorescence properties of the dye molecules.
Carbene‐Stabilized Exceptional Silicon Halides
Authors: Khan Shabana , Roesky Herbert W.
Published: July 2018

The isolation of stable carbenes, such as N‐heterocyclic carbenes, cyclic alkyl amino carbenes, and abnormal N‐heterocyclic carbenes, has encouraged synthetic chemists to use them as neutral ligands for stabilizing unusual compounds with main group elements. In this Minireview, an overview is provided of the recent developments in the chemistry of carbene‐stabilized silicon halides, in which the silicon atoms are in low oxidation state. The structural diversities emanating from the differences in the HOMO–LUMO gaps of various carbenes will also be discussed.
Listeriolysin O Binding Affects Cholesterol and Phospholipid Acyl Chain Dynamics in Fluid Cholesterol‐Rich Bilayers
Authors: Kozorog Mirijam , Sani Marc‐Antoine , Separovic Frances , Anderluh Gregor
Published: July 2018

Listeriolysin O (LLO) is a pore‐forming toxin that enables survival and cell‐to‐cell spread of foodborne bacterial pathogen Listeria monocytogenes, which is responsible for the life‐threatening disease, listeriosis. LLO–membrane interactions are crucial for pathogenicity of Listeria, but remained unexplained in detail at the molecular level. Here we addressed them by means of 2H, 31P, 13C and 19F solid‐state NMR spectroscopy. Different fluid and ordered cholesterol‐rich membrane lipid bilayer systems were prepared and checked for the integrity and properties in the presence of LLO. LLO has significantly changed dynamics of phospholipid acyl chains of more fluid cholesterol‐rich bilayers, whereas the lipid bilayer organization was not affected. LLO has also affected cholesterol dynamics by increasing the intensity of low frequency motions, indicating direct interactions of LLO with cholesterol. Additionally, the LLO protein was shown to interact differently with lipid membranes, depending on the properties of cholesterol‐rich membranes. The presented results, therefore, provide new insights into the interactions of the bacterial toxin LLO with cholesterol‐rich membrane systems.
Understanding Thermal and Photochemical Aryl–Aryl Cross‐Coupling by the AuI/AuIII Redox Couple
Authors: Bhattacharjee Rameswar , Datta Ayan
Published: July 2018

Systematic mechanistic investigations of the gold(I)/gold(III) redox‐controlled aryl–aryl cross‐coupling reaction have been performed by using both a thermal and photochemical approach. Electron‐deficient and electron‐rich arenes were considered as the coupling partners of the reaction. Based on transition‐state modeling and distortion/interaction analyses, it is shown that AuI prefers to react with electron‐deficient arenes whereas AuIII likes to activate electron‐rich arenes. This orthogonal reactivity of gold makes it an efficient catalyst for the aryl–aryl cross‐coupling reaction. The crucial role of the carboxylate ligand in the reaction has been elucidated through analysis of the transition states. It is shown that due to the presence of two coordination sites, a carboxylate ligand can stabilize the transition state more efficiently than other monodentate ligands such as chloride (Cl−). Moreover, carbon−boron transmetalation is shown to be favorable over direct C−H metalation, hence reactions initialized by C−B transmetalation are expected to be much faster and selective. Additionally, a dual photoredox/gold catalyst was employed to access the AuI/AuIII catalytic cycle for the cross‐coupling reaction. [Ru(bpy)3]2+ was used as the photoredox catalyst for the reaction, which, on excitation, transfers an electron to one of the coupling partners, namely a diazonium salt (ArN2+), and initializes the cycle.
Mutations of Histidine 13 to Arginine and Arginine 5 to Glycine Are Responsible for Different Coordination Sites of Zinc(II) to Human and Murine Peptides
Authors: Aliès Bruno , Borghesani Valentina , Noël Sabrina , Sayen Stephanie , Guillon Emmanuel , Testemale Denis , Faller Peter , Hureau Christelle
Published: July 2018

Because mice and rats do not naturally develop Alzheimer's disease, genetically modified animals are required to study this pathology. This striking difference in terms of disease onset could be due to three alterations in the murine sequence (R5G, Y10F and H13R) of the amyloid‐β peptide with respect to the human counterpart. Whether the metal‐ion binding properties of the murine peptide are at the origin of such different amyloidogenicity of the two peptides is still an open question. Herein, the main zinc binding site to the murine amyloid‐β at physiological pH has been determined through the combination of several spectroscopic and analytical methods applied to a series of six peptides with one or two of the key mutations. These results have been compared with the zinc binding site encountered in the human peptide. A coordination mechanism that demonstrates the importance of the H13R and R5G mutations in the different zinc environments present in the murine and human peptides is proposed. The nature of the minor zinc species present at physiological pH is also suggested for both peptides. Finally, the biological relevance and fallouts of the differences determined in zinc binding to human versus murine amyloid‐β are also discussed.
Template‐Directed Synthesis of an Inverted Spiro Architecture
Authors: Wanner Martin J. , Steemers Luuk , Uiterweerd Michiel T. , Klijn Raquel S. , Ehlers Andreas W. , van Maarseveen Jan H.
Published: July 2018

The regular bicyclic spiro motif is highly abundant given its synthetic accessibility while the diastereomer—virtually obtained through inversion at the central atom—is almost unknown. We have developed methodology to access the elusive inverted spiro architecture by employing a covalent template‐directed approach. Comparison with the regular spiro bicycle analog unequivocally established the diastereomeric relationship, providing insight into the fascinating stereochemical and structural properties.
Photochemistry of OPN: Formation of Cyclic PON and Reversible Combination with Carbon Monoxide
Authors: Wu Zhuang , Song Chao , Liu Jie , Lu Bo , Lu Yan , Trabelsi Tarek , Francisco Joseph S. , Zeng Xiaoqing
Published: July 2018

Cyclic PON, a first 16‐electron triatomic ring consisting of two first‐row elements, has been generated through 193 nm laser photolysis of OPN in cryogenic matrices. When the photolysis (365 nm) was performed in the presence of CO, OPN combines CO and furnishes an exotic acyclic molecule OPNCO. Upon the 193 nm laser irradiation, OPNCO dissociates mainly to OPN and CO with traces of PN and CO2. The identification of cyclic PON and OPNCO with IR spectroscopy is supported by 15N‐labeling experiments and quantum chemical calculations.
Photocatalyzed Intermolecular Aminodifluoromethylphosphonation of Alkenes: Facile Synthesis of α,α‐Difluoro‐γ‐aminophosphonates
Authors: Yang Qiang , Li Chong , Qi Zhi‐Chao , Qiang Xiao‐Yue , Yang Shang‐Dong
Published: July 2018

An efficient and practical method for the synthesis of α,α‐difluoro‐γ‐aminophosphonates through photocatalyzed intermolecular aminodifluoromethylphosphonation of alkenes has been developed. In this reaction, difluoromethylphosphonate is used as an important fluorinated reagent. Furthermore, the mild reaction conditions, simple operation, and broad substrate scope make this protocol very practical and attractive. The derivatization reaction in the synthesis of difluoromethylphosphonated chiral binaphthylamine ligands and α,α‐difluoro‐γ‐aminophosphoric acid highlight the applicability of this method.
Dismantling of Vinyl Ethers by Pentanuclear [(iPr3P)Ni]5H6: Facile Cooperative C−O, C−C and C−H Activation Pathways
Authors: Shoshani Manar M. , Semeniuchenko Volodymyr , Johnson Samuel A.
Published: July 2018

The [(iPr3P)Ni]5H6 cluster (1) and H2C=CHOtBu react at room temperature to form the new pentanuclear NiH carbide [(iPr3P)Ni]5H4(C)(CO) (3), along with an equivalent of isobutylene. This transformation requires the activation of multiple unreactive bonds, including C−H, C−C, and C(sp3)−O bond cleavage. Analysis of the reaction mixture by 1H NMR revealed the production of two additional paramagnetic species, assigned as [(iPr3P)Ni]4H4(C‐CH3)NiOtBu (4 a) and [(iPr3P)Ni]4H4(C‐CH2OtBu)NiOtBu (5 a), which arise from C(sp2)−O bond cleavage and CH bond rearrangements. The reaction of 1 with H2C=CHOSiMe2CH2Ph produced the isolable 4 a analogue [(iPr3P)4Ni5]H4(CCH3)(OSiMe2CH2Ph) (4 c). An isolable analogue of 5 a was obtained from the reaction of 1 with H2C=CHOAd (Ad=1‐admantyl), which produced [(iPr3P)4Ni5]H4(CCH2OAd)(OAd) (5 d). The utilization of both cluster faces and vertices for bonding substrate fragments in these transformations demonstrates the remarkable flexibility of the robust Ni5H4 core in the cooperative activation of multiple C−O, C−C and C−H bonds.
Internal chirality descriptors iR and iS and ire and isi. A proposed notation to extend the usefulness of the R/S system by retaining the sense of stereochemistry in cases of ligand ranking changes
Authors: Klika Karel D. , Wzorek Alicja , Soloshonok Vadim A.
Published: July 2018

The R/S system, universally applied for indicating the absolute configuration of a structure, is extremely adept for conveying the absolute configuration unequivocally. However, it suffers from one limitation, viz that due to CIP priority rules the rankings of the ligands attached to an asymmetric center can be altered upon a change in a ligand leading to a change in the designated configuration even if bonds to the asymmetric center were not actually formed or broken. This means that the sense of stereochemistry in situations such as within a set of compounds where family relationships are of focus or where the sense of the stereochemical course of a reaction is of interest can be lost or confusion may occur. This shortcoming is easily remedied though by defining a fixed ranking for a particular ligand in the system under study, eg, the ligand at which the change has occurred. The configurations are then expressed as iR or iS, akin to the R and S descriptors, for sp3‐hybridized tetrahedral chiral structures and similarly, as ire and isi faces, akin to the re and si descriptors, for sp2‐hybridized trigonal prochiral structures. All in all, the notation can be considered as an auxiliary to extend the usefulness of the R/S system. Thus, the proposed iR/iS notation could find profitable use in comparative studies where there is a need to avoid confusion arising from changing assignments due to priority rules or to expedite the ease of comprehension. Moreover, in the current digital age, the facile retrieval of stereochemically clear data by machines is highly desirable—something that the iR/iS notation is readily amenable to.
Stereoselective uptake and degradation of (±)‐o,p‐DDD pesticide stereomers in water‐sediment system
Authors: Basheer Al Arsh , Ali Imran
Published: July 2018

The environmental stereoselective uptake and degradation of (±)‐o,p‐DDD pesticide stereomers in water‐sediment system are described. The results were analyzed by artificial neural network model. The optimized experimental parameters were concentration of o,p‐DDD streamers (7.0 μg L−1), experimental time (60 min), pH (6), dose (5.0 g L−1), and temperature (25°C). The maximum uptake and degradation were 87% and 85% and 33.0% and 30.5% for (−)‐ and (+)‐stereomers of o,p‐DDD in 15‐day time. Both uptake and degraded phenomenon showed first‐order rate reaction. Thermodynamic variables indicated exothermic nature of uptake and degradation processes. The uptake and degradation were slightly higher for (−)‐stereomer than (+)‐stereomer of o,p‐DDD. It was assumed that both uptake and degradation processes are accountable for the removal of the streomers of o,p‐DDD from earth's ecosystem, but the uptake is responsible for major contribution. The magnitudes of relative errors obtained by artificial neural network model were in the range of ±0.2 to 3.5, indicating good applicability of the experimental data. The results are very useful to control the environmental contamination due to the chiral o,p‐DDD pesticide as its two enantiomers have different ecological toxicities.
Creation of a myosin Va‐TAP‐tagged mouse and identification of potential myosin Va‐interacting proteins in the cerebellum
Authors: Alexander Christopher J. , Wagner Wolfgang , Copeland Neal G. , Jenkins Nancy A. , Hammer John A.
Published: July 2018

The actin‐based motor myosin Va transports numerous cargos, including the smooth endoplasmic reticulum (SER) in cerebellar Purkinje neurons (PNs) and melanosomes in melanocytes. Identifying proteins that interact with this myosin is key to understanding its cellular functions. Toward that end, we used recombineering to insert via homologous recombination a tandem affinity purification (TAP) tag composed of the immunoglobulin G‐binding domain of protein A, a tobacco etch virus cleavage site, and a FLAG tag into the mouse MYO5A locus immediately after the initiation codon. Importantly, we provide evidence that the TAP‐tagged version of myosin Va (TAP‐MyoVa) functions normally in terms of SER transport in PNs and melanosome positioning in melanocytes. Given this and other evidence that TAP‐MyoVa is fully functional, we purified it together with associated proteins directly from juvenile mouse cerebella and subjected the samples to mass spectroscopic analyses. As expected, known myosin Va‐binding partners like dynein light chain were identified. Importantly, numerous novel interacting proteins were also tentatively identified, including guanine nucleotide‐binding protein G(o) subunit alpha (Gnao1), a biomarker for schizophrenia. Consistently, an antibody to Gnao1 immunoprecipitates myosin Va, and Gnao1’s localization to PN dendritic spines depends on myosin Va. The mouse model created here should facilitate the identification of novel myosin Va‐binding partners, which in turn should advance our understanding of the roles played by this important myosin in vivo.
Domain knowledge specification for energy tuning
Authors: Kumaraswamy Madhura , Chowdhury Anamika , Gerndt Michael , Bendifallah Zakaria , Bouizi Othman , Locans Uldis , Říha Lubomír , Vysocký Ondřej , Beseda Martin , Zapletal Jan
Published: July 2018

To overcome the challenges of energy consumption of HPC systems, the European Union Horizon 2020 READEX (Runtime Exploitation of Application Dynamism for Energy‐efficient Exascale computing) project uses an online auto‐tuning approach to improve energy efficiency of HPC applications. The READEX methodology pre‐computes optimal system configurations at design‐time, such as the CPU frequency, for instances of program regions and switches at runtime to the configuration given in the tuning model when the region is executed. READEX goes beyond previous approaches by exploiting dynamic changes of a region's characteristics by leveraging region and characteristic specific system configurations. While the tool suite supports an automatic approach, specifying domain knowledge such as the structure and characteristics of the application and application tuning parameters can significantly help to create a more refined tuning model. This paper presents the means available for an application expert to provide domain knowledge and presents tuning results for some benchmarks.
Kinetics of Reversible Protonation of Transient Neutral Guanine Radical in Neutral Aqueous Solution
Authors: Morozova Olga B. , Fishman Natalya N. , Yurkovskaya Alexandra V.
Published: July 2018

Time‐resolved chemically induced dynamic nuclear polarization (TR‐CIDNP) is applied to follow transformation of the short‐lived neutral guanine radical into a secondary guanine radical by its protonation, presumably at position N7. In the initial step the photoreaction of guanosine‐5′‐monophosphate (GMP) with triplet excited 3,3′,4,4′‐tetracarboxy benzophenone (TCBP) leads to formation of the neutral radical G(−H).. The evidence of the radical conversion is based on the inversion of CIDNP sign for TCBP and GMP protons on the microsecond timescale as a result of the change in magnetic resonance parameters in the pairs of TCBP and GMP radicals due to structural changes of the GMP radical. Acceleration of the CIDNP sign change upon addition of phosphate (proton donor) confirms that the radical transformation responsible for the observed CIDNP kinetics is protonation of the neutral guanine radical with formation of the newly characterized cation radical, (G.+)′. From the full analysis of the pH‐dependent CIDNP kinetics, the protonation and deprotonation behaviour is quantitatively characterized, giving pKa=8.0±0.2 of the cation radical (G.+)′.
Capture Hi‐C Library Generation and Analysis to Detect Chromatin Interactions
Authors: Orlando Giulia , Kinnersley Ben , Houlston Richard S.
Published: July 2018

Chromosome conformation capture (3C), coupled with next‐generation sequencing (Hi‐C), provides a means for deciphering not only the principles underlying genome folding and architecture, but more broadly, the role 3D chromatin structure plays in gene regulation and the replication and repair of DNA. The recently implemented modification, in situ Hi‐C, maintains nuclear integrity during digestion and ligation steps, reducing random ligation of Hi‐C fragments. Although Hi‐C allows for genome‐wide characterization of chromatin contacts, it requires high‐depth sequencing to discover significant contacts. To address this, Capture Hi‐C (CHi‐C) enriches standard Hi‐C libraries for regions of biological interest, for example by specifically targeting gene promoters, aiding identification of biologically significant chromatin interactions compared to conventional Hi‐C, for an equivalent number of sequence reads. Illustrating the application of CHi‐C applied to genome‐wide analysis of chromatin interactions with promoters, we detail the protocols for in situ Hi‐C and CHi‐C library generation for sequencing, as well as the bioinformatics tools for data analysis. © 2018 by John Wiley & Sons, Inc.
Physiological Role of Vascular Endothelial Growth Factors as Homeostatic Regulators
Authors: Bates David O. , Beazley‐Long Nicholas , Benest Andrew V. , Ye Xi , Ved Nikita , Hulse Richard P. , Barratt Shaney , Machado Maria J. , Donaldson Lucy F. , Harper Steven J. , Peiris‐Pages Maria , Tortonese Domingo J. , Oltean Sebastian , Foster Rebecca R.
Published: July 2018

The vascular endothelial growth factor (VEGF) family of proteins are key regulators of physiological systems. Originally linked with endothelial function, they have since become understood to be principal regulators of multiple tissues, both through their actions on vascular cells, but also through direct actions on other tissue types, including epithelial cells, neurons, and the immune system. The complexity of the five members of the gene family in terms of their different splice isoforms, differential translation, and specific localizations have enabled tissues to use these potent signaling molecules to control how they function to maintain their environment. This homeostatic function of VEGFs has been less intensely studied than their involvement in disease processes, development, and reproduction, but they still play a substantial and significant role in healthy control of blood volume and pressure, interstitial volume and drainage, renal and lung function, immunity, and signal processing in the peripheral and central nervous system. The widespread expression of VEGFs in healthy adult tissues, and the disturbances seen when VEGF signaling is inhibited support this view of the proteins as endogenous regulators of normal physiological function. This review summarizes the evidence and recent breakthroughs in understanding of the physiology that is regulated by VEGF, with emphasis on the role they play in maintaining homeostasis. © 2017 American Physiological Society.Compr Physiol8:955‐979, 2018.
Biological responses to environmental contamination. How can metal pollution impact signal honesty in avian species?
Authors: Pacyna Aneta Dorota , Ruman Marek , Mazerski Jan , Polkowska Żaneta
Published: July 2018

Environmental pollution, for example with metals, can significantly affect the ecosystem balance leading to severe changes. Biologically active pigments are relevant for the appearance and condition of birds. Melanin and carotenoid particles are the most frequently deposited pigments in avian integument. They are responsible for the majority of colors of bird plumage. The phenotypic expression can be affected by metal contamination. It can be manifested as color bleaching or differences in the size of plumage badges. In this study, we performed a comprehensive review of related studies in order to estimate the underlying population effect of this potential dependency. The study is based on the review of the literature regarding several avian species. It was designed to identify an area where the effect of the exposure is still poorly known. The analysis was specifically conducted to investigate the correlation between trace element concentration and eumelanin deposition. Moreover, we searched for factors that could affect spectral properties of feathers with carotenoid‐based pigmentation. As a result, we found carotenoid‐based pigmentation to be of a good use in terms of visual condition assessment. Changes in melanin‐based pattern should be analyzed separately for eu‐ and pheomelanin as well as for a range of essential and toxic elements. Comprehensive studies on the subject are still scarce. Therefore, the issue requires further investigation.
Cleavage of C–C and C–O Bonds to Form C–C Bonds: Direct Cross‐Coupling between Acetylenic Alcohols and Benzylic Carbonates
Authors: Mi Zhiyuan , Tang Jiahao , Guan Zhipeng , Shi Wei , Chen Hao
Published: July 2018

A palladium‐catalyzed cross‐coupling reaction between C(sp) and C(sp3) centers was achieved in excellent yields via C–C bond cleavage and C–O bond cleavage. This procedure uses relatively stable acetylenic alcohols as reactants instead of unstable/volatile terminal alkynes. The use of benzylic carbonates also avoids the involvement of benzyl halides, making this method more practical in synthesis. Ligands play an important role in the procedure and K2CO3 accelerates the reaction.
Multi‐Gram Scale Synthesis of 1,2,3‐Triazolium Ionic Liquids and Assay of Their Resistance towards Bases
Authors: Raiguel Stijn , Thomas Joice , Binnemans Koen , Dehaen Wim
Published: July 2018

An easily upscalable synthesis method for 1,2,3‐triazolium ionic liquids is presented. Several ionic liquids were synthesized and characterized. The influence of the side chain structure on the base‐stability was investigated. One example, functionalized with linear alkyl side chains, was found to exhibit excellent stability against hot concentrated NaOH solutions and Grignard reagents.
Protesting to challenge or defend the system? A system justification perspective on collective action
Authors: Osborne Danny , Jost John T. , Becker Julia C. , Badaan Vivienne , Sibley Chris G.
Published: July 2018

Social identity, shared grievances, and group efficacy beliefs are well‐known antecedents to collective action, but existing research overlooks the fact that collective action often involves a confrontation between those who are motivated to defend the status quo and those who seek to challenge it. Using nationally representative data from New Zealand (Study 1; N = 16,147) and a large online sample from the United States (Study 2; N = 1,513), we address this oversight and demonstrate that system justification is negatively associated with system‐challenging collective action, but positively associated with system‐supporting collective action, for members of both low‐status and high‐status groups. Group identification, group‐based injustice, group‐based anger, and system‐based dissatisfaction/anger mediated these relationships. These findings constitute the first empirical integration of system justification theory into a model of collective action that explains when people will act collectively to challenge—and, just as importantly, defend—the status quo.
Evaluation of passive sampling polymers and nonequilibrium adjustment methods in a multiyear surveillance of sediment porewater PCBs
Authors: Sanders James P. , Andrade Natasha A. , Ghosh Upal
Published: July 2018

Polymeric passive sampling devices are increasingly used to measure low-level, freely dissolved concentrations of hydrophobic organic contaminants in environmental waters. A range of polymers have been used for this purpose, and several different methods of accounting for nonequilibrium using performance reference compounds (PRCs) have been proposed. The present study explores the practical impacts of these decisions in an applied context using results from a multiyear passive sampling surveillance of polychlorinated biphenyl concentrations in sediment porewater at a contaminated marsh amended with activated carbon (AC) sorbent materials. In a series of 5 sampling events spanning almost 2 yr, we deployed polyoxymethylene and polyethylene samplers and calculated porewater concentrations with 5 different PRC adjustment methods. The results provide a basis for evaluating amendment performance by showing reductions of 34 to 97% in amended sediment porewater concentrations. They also provide a quantitative underpinning for discussions of the differences between sampling polymers, selection of PRCs, generation of high-resolution vertical profiles of porewater concentrations, and a comparison of PRC adjustment methods. For unamended sediment, older methods based on first-order kinetics agreed well with a recently developed method based on diffusion into and out of sediment beds. However, the sediment diffusion method did not work well for the sediments amended with AC. Environ Toxicol Chem 2018;37:2487–2495. © 2018 SETAC
Interaction between magnesium hydroxide and microencapsulated red phosphorus in flame‐retarded high‐impact polystyrene composite
Authors: Liu Jichun , Guo Yingbin , Chang Haibo , Li Hang , Xu Airong , Pan Bingli
Published: July 2018

High‐impact polystyrene (HIPS) flame retarded by magnesium hydroxide (MH) alone or in combination with microencapsulated red phosphorus (MRP) was prepared by melt compounding, and the interaction between MH and MRP was investigated by limiting oxygen index, UL‐94 vertical burning test, cone calorimeter test, X‐ray diffraction, thermal analysis, and scanning electron microscopy. Obvious synergism between MH and MRP on the flame retardancy of HIPS is found. The introduction of a small amount of MRP can accelerate the endothermic degradation of MH apparently at high temperature both in air and in nitrogen. Phosphoric acid (H3PO4) derivatives are produced in situ by the MH/MRP mixture upon thermal degradation in both atmospheres, which can act as char‐forming agents and promote charring of the polymer upon burning. The burnt residue of the HIPS/MH/MRP composite is composed of a tiny amount of crystalline MgO, noncrystalline black char, and a series of noncrystalline phosphorus‐containing magnesium phosphate compounds.
An approximation formula for normal implied volatility under general local stochastic volatility models
Authors: Karami Yasaman , Shiraya Kenichiro
Published: July 2018

We approximate normal implied volatilities by means of an asymptotic expansion method. The contribution of this paper is twofold: to our knowledge, this paper is the first to provide a unified approximation method for the normal implied volatility under general local stochastic volatility models. Second, we applied our framework to polynomial local stochastic volatility models with various degrees and could replicate the swaptions market data accurately. In addition we examined the accuracy of the results by comparison with the Monte‐Carlo simulations.
Course of neuropsychiatric symptoms in dementia: 5‐year longitudinal study
Authors: Vik‐Mo Audun Osland , Giil Lasse Melvaer , Ballard Clive , Aarsland Dag
Published: July 2018

Objective

Neuropsychiatric symptoms (NPS) in dementia are frequent and challenging for patients, carers, and the health care system, but few long‐term studies exist. We analyse the longitudinal course of NPS in patients with mild dementia.

Methods

A longitudinal cohort study of 223 patients with mild dementia and annual assessments using the Neuropsychiatric Inventory (NPI) for 5 years.

Results

A total 1043 NPI assessments, representing 97% of all possible measurements of living cohort members, were analysed. Neuropsychiatric symptoms were common at baseline, and only a moderate increase in total NPS score from 15 to 17 with no increase in the proportion with high NPI total scores. Ninety seven percent scored ≥16, and 49% scored ≥36 on NPI total score at least once during follow‐up. Individual NPS fluctuated and often reappeared. The most common symptoms ever reported was apathy (83%), depression (63%), appetite (63%), and aberrant motor behavior (60%). Cognitive decline was associated with higher NPI total score and several NPI items, but only the frequency of apathy increased significantly with time. Lewy body dementia was associated with higher NPI total score and psychotic symptoms. Alzheimer's disease was associated with increase in apathy.

Conclusions

Severe NPS are already common at time of dementia diagnosis, and the increase in overall severity over 5 years was moderate. Individual symptoms tend to fluctuate over time within patients and correspond to states rather than traits. These findings highlight the need to focus on, and plan for, NPS as part of dementia pathway, and are relevant for clinical trial design.
Time, memory, and the legacy of Howard Eichenbaum
Authors: Ranganath Charan
Published: July 2018

Over the past 15 years, there has been an explosion of new research on the role of the hippocampus in the representation of information about time in memory. Much of this work was inspired by the ideas and research of Howard Eichenbaum, who made major contributions to our understanding of the neurobiology of episodic memory and the neural representation of time. In this article, I will review evidence regarding the role of time in understanding hippocampal function. This review will cover a broad range of evidence from studies of humans and nonhuman animals with a narrative arc that follows Howard's major discoveries. These studies demonstrate that the hippocampus encodes information in relation to an episodic context, and that time, as well as space, serves to define these contexts. Moreover, the research has shown that the hippocampus can encode temporal, spatial, and situational information in parallel. Building on this work, I present a new framework for understanding temporal structure in human episodic memory. I conclude by outlining current controversies and new questions that must be addressed by the field in the years to come.
The other's perception of a streamflow sample: From a bottle of water to a data point
Authors: Brunner Manuela , Pool Sandra , Kiewiet Leonie , Acheson Elise
Published: July 2018

In scientific communication, ambiguities in term usage can go unnoticed due not only to the distance between reader and writer but also to the existence of highly specialized scientific subcommunities. This commentary therefore aims at raising awareness about the use of terms that have different meanings within different hydrological subcommunities such as field hydrology, hydrological modelling, or statistical hydrology. To do so, we discuss the use of the following commonly used hydrological terms: sample, runoff, discharge, and streamflow. We performed three types of analyses to provide evidence of term usage and understanding, including both qualitative and quantitative approaches: a drawing exercise, a survey, and a literature corpus analysis. These analyses allow for a comparison of spontaneous definitions and the actual use of these terms in scientific publications. Our various information sources revealed that the dialogue between hydrologists within and across subdisciplines is substantially influenced by personal conceptualizations of terms that are not always shared across conversational partners. The terms discussed and illustrated in this commentary have to be seen as a small sample used to demonstrate the need for a thoughtful use of hydrological terms when communicating research, not only to a general audience but even across subdisciplines within hydrology.
Long non‐coding RNA lnc‐PCTST predicts prognosis through inhibiting progression of pancreatic cancer by downregulation of TACC‐3
Authors: Wang Yandong , Ding Xiangya , Hu Hao , He Yuan , Lu Zipeng , Wu Pengfei , Tian Lei , Xia Tianfang , Yin Jie , Yuan Hao , Shi Guodong , Liu Dongfang , Jiang Kuirong , Miao Yi
Published: July 2018

Pancreatic cancer (PC), which is one of the most lethal of malignancies and a major health burden, is associated with a dismal prognosis despite current therapeutic advances. Numerous long noncoding RNAs (lncRNA) have shown to be essential for PC tumorigenesis and progression. Nevertheless, the exact expression pattern of lnc‐PCTST and its clinical significance still remain unclear. This study investigates the expression pattern of lnc‐PCTST and its associated mRNA in three paired PC tissues and adjacent non‐tumor tissues by Microarray‐coarray approach. Briefly, our data demonstrated that lnc‐PCTST expression is down‐regulated in PC tissues. Also, lnc‐PCTST has shown to be negatively correlated with transforming acidic coiled‐coil 3 (TACC‐3) expression. This expression pattern was further confirmed following qRT‐PCR validation of 34 out of 48 paired cancer tissues. Furthermore, lnc‐PCTST overexpression in PC cell lines inhibited cell proliferation and invasion in vitro, and tumorigenesis in vivo (using nude mice as animal model), but did not altered cell migration. Moreover, lnc‐PCTST overexpression increased E‐cadherin and repressed vimentin expression in vitro. Additionally, TACC‐3 knockdown simulated the inhibiting effect of lnc‐PCTST overexpression on PC cell lines, and the impaired proliferation, invasion effect and E‐cadherin, vimentin expression on lnc‐PCTST over‐expressed cell lines can be rescued by overexpressed TACC‐3. Significantly, the expression of lnc‐PCTST was closely associated with its genomic neighboring gene TACC‐3 and inhibited its promoter activity. In conclusion, lnc‐PCTST is a potential tumor suppressor in PC, which inhibits cell proliferation, invasion, tumorigenesis and EMT by modulating TACC‐3.
Plant galactolipid dLGG suppresses lung metastasis of melanoma through deregulating TNF‐α‐mediated pulmonary vascular permeability and circulating oxylipin dynamics in mice
Authors: Yang Chung‐Chih , Chang Cheng‐Kuei , Chang Meng‐Ting , Shyur Lie‐Fen
Published: July 2018

This study demonstrates the bioefficacy and gives mechanistic insights into a plant galactolipid 1,2‐di‐O‐linolenoyl‐3‐O‐β‐galactopyranosyl‐sn‐glycerol (dLGG) against metastatic melanoma using a syngeneic mouse model implanted with B16COX‐2/Luc melanoma. dLGG‐20 (p.o. dLGG 20 mg/kg) and anti‐cancer drug CP‐2 (i.p. cisplatin 2 mg/kg) treatment significantly inhibited lung metastasis of melanoma in mice 91 and 57%, respectively, as determined by bioluminescence intensity. Moreover, dLGG‐20 and CP‐2 treatment prolonged mouse mean survival time. dLGG‐20 treatment significantly inhibited the expression levels of several molecular markers, that is, PCNA, MMP2, COX‐2, VEGF, vimentin, snail, TGF‐β, β‐catenin, TNF‐α, PD‐1 and PD‐L1 in mouse lung tissues compared to tumor control mice. Significant inhibition of macrophage and neutrophil infiltration and promotion of CD8 + Tc cell recruitment in the lung microenvironment was observed in dLGG‐20‐treated mice. A LC/MS‐based comparative oxylipin metabolomics study showed that dLGG‐20 treatment significantly induced (5.0‐ to 12.8‐fold) the 12/15‐LOX catalyzed oxylipin products in mouse serum including 17‐HDHA from DHA, 15‐HEPE from EPA, 8‐ and 12‐HETEs from AA, and CYP450‐derived 20‐HETE from AA. CP‐2 treatment increased 12/15‐LOX derived 8‐, 11‐ and 12‐HETEs from AA, and CYP450 derived 11,12‐EET from AA ad 9,10‐DHOME from LA by 5.3‐ to 8.1‐fold. Of note, dLGG and 17‐HDHA were more effective than CP in preventing B16 melanoma cell‐induced pulmonary vascular permeability in mice through inhibition of TNF‐α production, up‐regulation of tight junction proteins claudin1 and ZO‐2 and deregulation of Src activation. In conclusion, this study shows the novel therapeutic effect of phytoagent dLGG and suggests its potential as a therapeutic agent for metastatic melanoma.
DNA methylation accumulation in gastric mucosa adjacent to cancer after Helicobacter pylori eradication
Authors: Tahara Sayumi , Tahara Tomomitsu , Horiguchi Noriyuki , Kato Takema , Shinkai Yasuko , Yamashita Hiromi , Yamada Hyuga , Kawamura Tomohiko , Terada Tsuyoshi , Okubo Masaaki , Nagasaka Mitsuo , Nakagawa Yoshihito , Shibata Tomoyuki , Yamada Seiji , Urano Makoto , Tsukamoto Tetsuya , Kurahashi Hiroki , Kuroda Makoto , Ohmiya Naoki
Published: July 2018

Molecular irreversibleness with Helicobacter pylori (H. pylori) infection might have a role in gastric tumorigenesis after H. pylori eradication. We performed comprehensive DNA methylation profiling of gastric mucosa after H. pylori eradication with or without gastric cancer. Using four different groups of biopsies obtained from gastric body without history of H. pylori infection (Hp‐), gastric body without cancer after H. pylori eradication (cancer‐free body), gastric body with early gastric cancer diagnosed after H. pylori eradication (EGC body) and their paired samples from adjacent mucosa of cancer (EGC ADJ), methylation status of five candidate genes (MYOD1, SLC16A12, IGF2, RORA and PRDM5) was examined by the bisulfite pyrosequencing. An Infinium Methylation EPIC BeadChip array was also used to characterize the methylation status of greater than 850,000 CpG sites. The EGC ADJ group showed highest methylation levels of five candidate genes among the four groups of biopsies. In the gastric body (cancer‐free body + EGC body), methylation levels were significantly decreased in patients with longer period after eradication, while such association was not observed in EGC ADJ group. Hyper methylated samples were associated with shorter telomere, an indicator for rapid cell turnover, and higher DNMT1 protein expression, an enzyme related to methyl transfer reaction. The genome‐wide methylation analysis demonstrated strikingly higher methylation levels especially at CpG islands in the EGC ADJ group. Exclusively hypermethylated promoter CpG islands in the same group frequently coded zinc finger proteins. Our data show that DNA methylation accumulation is associated with molecular irreversibleness and gastric carcinogenesis after H. pylori eradication.
Quantitative in vivo detection of adipose tissue browning using diffuse reflectance spectroscopy in near‐infrared II window
Authors: Dev Kapil , Dinish U. S , Chakraborty Smarajit , Bi Renzhe , Andersson‐Engels Stefan , Sugii Shigeki , Olivo Malini
Published: July 2018

White adipose tissue (WAT) and brown adipose tissue (BAT) biologically function in an opposite way in energy metabolism. BAT induces energy consumption by heat production while WAT mainly stores energy in the form of triglycerides. Recent progress in the conversion of WAT cells to “beige” or “brown‐like” adipocytes in animals, having functional similarity to BAT, spurred a great interest in developing the next‐generation therapeutics in the field of metabolic disorders. Though magnetic resonance imaging and positron emission tomography could detect classical BAT and WAT in animals and humans, it is of a great challenge in detecting the “browning” process in vivo. Here, to the best of our knowledge, for the first time, we present a simple, cost‐effective, label‐free fiber optic‐based diffuse reflectance spectroscopy measurement in the near infrared II window (~1050‐1400 nm) for the quantitative detection of browning in a mouse model in vivo. We could successfully quantify the browning of WAT in a mouse model by estimating the lipid fraction, which serves as an endogenous marker. Lipid fraction exhibited a gradual decrease from WAT to BAT with beige exhibiting an intermediate value. in vivo browning process was also confirmed with standard molecular and biochemical assays.
Molecular docking study and structure‐based design of novel camptothecin analogues used as topoisomerase I inhibitor
Authors: Arthur David Ebuka , Uzairu Adamu
Published: July 2018

The paper describes the molecular docking study of the inhibition of human topoisomerase I (Top1), which is the molecular target of a diverse set of anticancer compounds such as glycinate, camptothecin, and its analogues. The reaction mechanisms involving their interaction with a transient Top1–DNA covalent complex inhibits the resealing of a single‐strand nick created by the enzyme to relieve superhelical tension in duplex DNA; this was confirmed using ICM‐Pro Molsoft program. Our research findings on this reaction indicate that its planner nature, the presence of some fragments on the lactone E‐ring, and the Pi–Pi interactions of the camptothecin drugs with DNA were directly responsible for its stable ternary complex with Top1. The molecular docking result of our study demonstrates that morpholinodoxorubicin (−32.835 kcal/mol), 9‐amino‐20‐RS‐camptothecin (−28.792 kcal), and camptothecin lysinate HCl (−28.224 kcal) best inhibit Top1 when compared with other National Service Center (NSC) compounds within our dataset. These compounds were further utilized in designing new potent antitumor compounds by attaching potent fragments to the lactone ring of the compounds. Most of these compounds were reported to be more active than the parent structure, some of which includes CLD‐12, CLD‐7, and CD‐9 with a binding affinity of −40.307, −36.743, and − 36.072 kcal/mol, respectively.
Association of single nucleotide polymorphisms in resistin gene with rheumatoid arthritis in a Chinese population
Authors: Li Hong‐Miao , Zhang Tian‐Ping , Li Xiao‐Mei , Pan Hai‐Feng , Ma Dong‐Chun
Published: July 2018

Background

Recent evidences have revealed that resistin is associated with the development of rheumatoid arthritis (RA). The aim of this study was to analyze the association of resistin gene single nucleotide polymorphisms (SNPs) with RA susceptibility.

Methods

In this study, we finally analyzed three resistin SNPs (rs1862513, rs3745368, and rs3745367) in 278 RA patients and 276 normal controls recruited from Chinese population using TaqMan SNP genotyping assays.

Results

There were no significant differences for the distribution of allele and genotype frequencies of these three SNPs between RA patients and normal controls (all P > .05). The genotype effects of dominant, recessive models were also analyzed, and no significant association was detected (all P > .05). Haplotype analysis suggested that the frequency of haplotype GAA was notably lower in RA patients in comparison with normal controls (OR = 0.317, 95% CI: 0.125‐0.807, P = .011).

Conclusion

In a ward, our results indicated that resistin gene polymorphisms might affect the genetic predisposition of RA in Chinese population.