bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultra‐Stable Asymmetric Supercapacitors Constructed by In‐Situ Electro‐Oxidation Activated Ni@CNTs Composites
Authors: Zhang Xiaojia , Wang Lei , Wei Zengxi , Zhang Guanhua , Zeng Wei , Fu Jiecai , Liu Quanhui , Duan Huigao
Published: August 2018

Up to now, it is still an enormous challenge to build high‐performance asymmetric supercapacitors showing long cycling life and superior rate capability. In this work, unique three‐dimensional nickel deposited onto carbon nanotubes (Ni@CNTs) composites are synthesized by a reduction and catalytic growth process with ethanol as both, reductive agent and green carbon source. Asymmetric supercapacitors are assembled by only using the Ni@CNTs composites as positive and negative electrodes with our concept “one for two”, in rational combination with electro‐oxidation activation. Here, the three‐dimensional CNTs are responsible for the electric double layer capacitance and the encapsulated NiOOH nanoparticles derived from electro‐oxidation reaction contribute to pseudocapacitance. The asymmetric devices exhibit remarkable cycling stability with 100 % capacitance retention even up to 60,000 cycles at a current density of 10 mA cm−2 and excellent rate capability with 72.9 % capacitance retention with the current density increasing from 5 to 50 mA cm−2. To better understand the electrochemical behavior, the relative contributions from electric double layer capacitance and pseudocapacitance of the positive electrode as well as the electrochemical kinetics of the devices are quantified.
Self‐Polymerized Disordered Carbon Enabling High Sodium Storage Performance through Expanded Interlayer Spacing by Bound Sulfur Atoms
Authors: Li Wei , Wang Kangli , Cheng Shijie , Jiang Kai
Published: August 2018

An effective strategy to fabricate sulfur‐doped carbon with tunable doping sites is developed using a one‐step pyrolytic technique. Applied as Na‐storage anode, this sulfur‐doped carbon exhibits high reversible capacity, excellent rate capability (330 mAh g−1 at 0.02 A g−1 and 158 mAh g−1 at 5 A g−1), as well as superior durability (159 mAh g−1 over 10000 cycles at 2 A g−1 with 95.7 % retention). Experimental characterization and theoretical calculation reveal that interlayer C−S−C bonds not only expand the d002 spacing, but also provide an alternative pathway for electron transport. This improves Na+ ion intercalation/deintercalation capability and electronic conductivity.
Hierarchical Shell‐Like ZSM‐5 with Tunable Porosity Synthesized by using a Dissolution–Recrystallization Approach
Authors: Lin Junzhong , Cichocka Magdalena O. , Peng Fei , Yang Taimin , Sun Junliang
Published: August 2018

Zeolites have been widely used in various fields in industry, such as catalysis, separation, and adsorption, etc. The small pore size of the micropores in the zeolite could lead to severe diffusion resistance in mass transfer. Numerous efforts have been dedicated to imposing hierarchical pore systems into zeolites by using templates or leaching methods. Here, we report the synthesis of single‐crystalline hierarchical shell‐like ZSM‐5 by utilizing a dissolution–recrystallization post‐treatment on mesoporous ZSM‐5. Tetrapropylammonium hydroxide solution was used in the post‐treatment. The hierarchical porosity in the crystalline shell can be controlled by adding sodium cations into the synthesis system. The hierarchical shell‐like ZSM‐5 reported here shows higher catalytic activity in acetalization reactions containing bulky molecules.
Microporous N,P‐Codoped Graphitic Nanosheets as an Efficient Electrocatalyst for Oxygen Reduction in Whole pH Range for Energy Conversion and Biosensing Dissolved Oxygen
Authors: Lin Deqing , Hu Chuangang , Chen Hao , Qu Jia , Dai Liming
Published: August 2018

Microporous N,P‐codoped graphitic nanosheets (N,P‐CMP‐1000) were synthesized by thermal annealing (1000 °C) of as‐synthesized conjugated microporous polymers (CMPs) in the presence of phytic acid, which can be used as an effective metal‐free electrocatalyst for the oxygen reduction reaction (ORR) for energy conversion. In the whole pH range (i.e. alkaline, acidic, and neutral solutions), the obtained N,P‐CMP‐1000 exhibits superior electrocatalytic activity for ORR with a low overpotential, high current density, and good stability. Furthermore, N,P‐CMP‐1000 can also be applied for electrochemically sensing dissolved oxygen (DO), with a high sensitivity (1.89 μA mg−1 L) and broad detection range (2.56 to 16.65 mg L−1) due to its good electrocatalytic performance towards ORR in neutral solution. In vitro cytotoxicity tests (CCK‐8 and Live/Dead Cell Double Staining Assay) of N,P‐CMP‐1000 extracts demonstrated its good biocompatibility to Human Corneal Epithelial Cells (HCEC), which shows its great potential as an eye‐wearable biosensor for sensing DO in tears.
Non‐Metal‐Heteroatom‐Doped Carbon Dots: Synthesis and Properties
Authors: Li Feng , Yang Dayong , Xu Huaping
Published: August 2018

Carbon dots (CDs) are new materials with applications in bioimaging, optical devices, catalysis, and many other fields. Their advantages, such as ease of large‐scale preparation, low‐costing precursors, highly tunable photoluminescence, satisfactory biocompatibility, and photostability against photobleaching, make them competitive alternatives to conventional semiconductor‐based quantum dots and organic dyes. To overwhelm other luminescent materials in applications, their functionalities still need to be improved in spite of the abovementioned advantages. In recent years, it has been proven that heteroatom doping is an effective approach to improve the optical and electronic performance of CDs by tuning their carbon skeleton matrices and chemical structures. In this review, the development of non‐metal‐heteroatom‐doped CDs, including heteroatom categories, preparation methods, and physicochemical properties, are discussed. Progressive trends in heteroatom‐doped CDs are also discussed at the end of this review.
Reaction Selectivity in On‐Surface Chemistry by Surface Coverage Control—Alkyne Dimerization versus Alkyne Trimerization
Authors: Klaasen Henning , Liu Lacheng , Meng Xiangzhi , Held Philipp Alexander , Gao Hong‐Ying , Barton Dennis , Mück‐Lichtenfeld Christian , Neugebauer Johannes , Fuchs Harald , Studer Armido
Published: August 2018

This work reports the influence of molecular coverage in on‐surface C−C‐bond formation on reaction outcome. 6‐Ethynyl‐2‐naphthoic acid (ENA) was chosen as organic component and Ag(111) as substrate. The alkyne moiety in ENA can either react by dimerization to ENA dimers (Glaser coupling or hydroalkynylation) or cyclotrimerization to generate a benzene core as connecting moiety. Dimer formation is preferred at high surface coverage whereas trimerization is the major reaction pathway at low coverage. Mechanistic studies are provided.
Perovskite Oxide LaNiO3 Nanoparticles for Boosting H2 Evolution over Commercial CdS with Visible Light
Authors: Xu Junli , Sun Chunfang , Wang Zhaoyu , Hou Yidong , Ding Zhengxin , Wang Sibo
Published: August 2018

LaNiO3/CdS heterojunction photocatalysts are constructed by compositing LaNiO3 nanoparticles with commercially available CdS, and are used for efficient photocatalytic splitting of H2O with visible light. The LaNiO3/CdS hybrids are characterized systematically using a series of physicochemical techniques. The photocatalytic activity of the perovskite hybrids is examined by H2 evolution with Na2S‐NaSO3 as the hole scavenger. The optimized LaNiO3/CdS sample without the assistance of any cocatalyst (e.g., Pt) delivers a high H2 production rate of 74 μmol h−1 (e.g., 3700 μmol h−1 g−1), which is substantially superior to the individual LaNiO3 and CdS. Besides, the composite photocatalyst also manifests high stability. The greatly improved H2 production performance of LaNiO3/CdS is attributed to the facilitated separation and transport of photoinduced charge carriers, as evidenced by photoelectrochemical (PEC) analyses, such as photoluminscence spectroscopy, transient photocurrent responses, and electrochemical impedance spectroscopy. Moreover, a probable photocatalytic mechanism of the H2 evolution reaction is proposed on the basis of the results of the catalysis evaluation and PEC tests.
Sodium Salicylate: An In‐Depth Thermal and Photophysical Study
Authors: Spielberg Eike T. , Campbell Paul S. , Szeto Kai C. , Mallick Bert , Schaumann Julian , Mudring Anja‐Verena
Published: August 2018

Sodium salicylate (2‐hydroxybenzoate) has been fully characterised by single‐crystal X‐ray diffraction (SCXRD), thermogravimetric analysis in combination with in operando FTIR spectroscopy and GC‐MS, as well as by UV/Vis absorption and photoluminescence spectroscopy backed up by DFT calculations. SCXRD revealed a layered crystal structure composed of ionic sheets formed by Na+–O contacts sandwiched between π‐stacked aromatic rings of the salicylate anion oriented perpendicular to the layer plane. Only weak van der Waals interactions hold the individual sheets together. No solid/solid or solid/liquid phase transitions were observed upon heating, but a three‐step decomposition was observed, with the first onset at 245 °C corresponding to concomitant release of CO2 and phenol. The UV/Vis absorption spectra show temperature‐dependent absorption bands at around 305 and/or 345 nm, which according to DFT calculations correspond to the absorption of the carboxylate or phenolate proton transfer species, respectively. In solution, indications of the phenolate species are found only in a very apolar solvent (cyclohexane). Because of excited‐state relaxation, emission always occurs from the phenolate structure, which explains the large Stokes shift.
Molecular Design towards Controlling Charge Transport
Authors: Awais Mohammad Ahmad , Cai Zhengxu , Zhang Na , Yu Luping
Published: August 2018

Organic electronics generally deals with bulk, statistically averaged electrical properties of organic materials. Single‐molecule electronic devices can then be viewed as linkers to these bulk properties. However, controlling charge transport in single‐molecule systems still remains a formidable task and has prevented proliferation of these systems from research laboratories to household electronics. This Concept article provides a general overview of the recent advances made by our group in the field. We will describe several concepts in designing molecular functions towards controlling charge transport through molecular systems. It should be noted, however, that this Concept article is by no means comprehensive and readers should look elsewhere for a more comprehensive picture of molecular electronics.
Novel Types of Hypermodified Fluorescent Phyllobilins from Breakdown of Chlorophyll in Senescent Leaves of Grapevine (Vitis vinifera)
Authors: Erhart Theresia , Mittelberger Cecilia , Liu Xiujun , Podewitz Maren , Li Chengjie , Scherzer Gerhard , Stoll Gertrud , Valls Josep , Robatscher Peter , Liedl Klaus R. , Oberhuber Michael , Kräutler Bernhard
Published: August 2018

The tetrapyrrolic chlorophyll catabolites (or phyllobilins, PBs) were analyzed in yellow fall leaves of the grape Chardonnay, a common Vitis vinifera white wine cultivar. The major fractions in leaf extracts of V. vinifera, tentatively assigned to PBs, were isolated and their structures elucidated. The dominant fraction is a dioxobilin‐type non‐fluorescent Chl‐catabolite of a previously observed type. Two less polar fluorescent PBs were characterized as a novel dioxobilin‐type fluorescent Chl‐catabolite with a bicyclo‐1′,6′‐glycosyl architecture, and its new fluorescent formyloxobilin‐type analogue. The discovery of persistent hypermodified fluorescent PBs with the architecture of bicyclo‐[17.3.1]‐PBs (bcPBs), suggests the activity of an unknown enzyme that forges the 20‐membered macroring at the tetrapyrrolic core of a fluorescent PB. bcPBs may play specific physiological roles in grapevine plants and represent endogenous anti‐infective agents, as found similarly for other organic bicyclo‐[n.3.1]‐1′,6′‐glycosyl derivatives.
Tenacic Acids: A New Class of Tenacious Binders to Metal Oxide Surfaces
Authors: Komati Rajesh , Mitchell Carl A. , LeBeaud Anastasia , Do Huy , Goloverda Galina Z. , Kolesnichenko Vladimir L.
Published: August 2018

The backbone of 2‐hydroxyisophthalic acid was identified as a potential metal oxide anchor because of the perfect alignment of all three of its donor groups for binding to inorganic surfaces. It can therefore be used in the design of organic linkers for metal oxide based hybrid materials. Optimized and scalable methods for the synthesis of 2‐hydroxyisophthalic acid (1) and its 5‐substituted derivatives: 5‐bromo‐ (2), 5‐sulfooxy‐ (3), 5‐hydroxy‐ (4), and 5‐PEG600 (5) are presented. Dynamic light scattering (DLS) demonstrated that compound 2 inhibits Fe(OH)3 precipitation when FeIII aqueous solutions are titrated with NaOH, while similar titrations in the presence of the structurally‐related isophthalic and salicylic acids, both missing the third donor group, show turbidity at pHs as low as 2.3 and 3.5, respectively. The adduct synthesized from 4.5 nm γ‐Fe2O3 nanoparticles and 5 is water‐, alcohol‐ and CH2Cl2‐soluble, and forms stable aqueous colloids in the pH range of 4.4–8.7. Moreover, at a pH close to neutral these colloids survive at 100 °C, demonstrating the high practicality of 2‐hydroxyisophthalic acid for nanoparticulate inorganic/organic hybrid material design.
Soluble Hetero‐Polyoxovanadates and Their Solution Chemistry Analyzed by Electrospray Ionization Mass Spectrometry
Authors: Warzok Ulrike , Mahnke Lisa K. , Bensch Wolfgang
Published: August 2018

Polyoxometalates (POMs) are an intriguing class of compounds due to their tremendous structural variety and the wide spectrum of resulting properties, which make them interesting for applications in fields such as catalysis, material science or nanotechnology. Their ability to form large supramolecular architectures by self‐assembly offers an entry to complex, functional systems. After an introduction into the structure and synthesis of POMs of the early transition metals, recently discovered water‐soluble antimonato polyoxovanadates (Sb‐POVs) and the investigation of their chemical reactivity are discussed. Electrospray ionization mass spectrometry (ESI‐MS) is presented as an analytical technique suitable to investigate the structure of complex POM assemblies in solution and to probe the underlying reactivity and formation mechanisms. This Minireview highlights the first studies on the soluble Sb‐POVs and how the knowledge of their reactivity obtained by ESI‐MS has fostered the syntheses of numerous novel Sb‐POV compounds.
The First Examples of Lithium‐Containing Mixed‐Alkali Strontium Borates with Different Dimensional Anionic Architectures and Short Cutoff Edges
Authors: Ma Ruru , Yang Yun , Hu Cong , Yang Zhihua , Pan Shilie
Published: August 2018

Three new mixed‐alkali strontium borates, Li2KSr6(BO3)5, Li2Rb7Sr24(BO3)19, and Li2Rb2SrB18O30, have been synthesized by the high‐temperature solution method by adjusting the molar ratios of the reactants. They represent the first examples of lithium‐containing mixed‐alkali strontium borates. The structures of the three compounds show different dimensional anionic architectures, with Li2KSr6(BO3)5 and Li2Rb7Sr24(BO3)19 possessing isolated BO3 units, whereas Li2Rb2SrB18O30 has three‐dimensional (3D)
open frameworks with three types of channels occupied by the strontium and rubidium atoms. Interestingly, Li2KSr6(BO3)5 is the first example of a
chain composed of LiO5 linked through the sharing of vertexes and edges. However, in Li2Rb7Sr24(BO3)19, isolated LiO3 units can be observed, which is also rare in borates. Detailed analysis and comparisons of the structures of the anhydrous mixed‐alkali‐ and alkaline‐earth‐metal borates and nine‐polymeric fundamental building blocks have been made. Furthermore, Li2Rb7Sr24(BO3)19 and Li2Rb2SrB18O30 present short cutoff edges (<190 nm), which was confirmed by the UV/Vis/NIR diffuse reflectance spectra. These attributes make them attractive for deep‐UV optical materials.
Synthesis of Thin‐Film Metal Pyrites by an Atomic Layer Deposition Approach
Authors: Wang Jue , Guo Zheng , Xiong Wei , Wang Xinwei
Published: August 2018

Late 3d transition metal disulfides (MS2, M=Fe, Co, Ni, Cu, Zn) can crystallize in an interesting cubic‐pyrite structure, in which all the metal cations are in a low‐spin electronic configuration with progressive increase of the eg electrons for M=Fe–Zn. These metal pyrite compounds exhibit very diverse and intriguing electrical and magnetic properties, which have stimulated considerable attention for various applications, especially in cutting‐edge energy conversion and storage technologies. The synthesis of the metal pyrites is certainly very important, because highly controllable, reproducible, and reliable synthesis methods are virtually essential for both fundamental materials research and practical engineering. In this Concept, a new approach of (plasma‐assisted) atomic layer deposition (ALD) to synthesize the thin‐film metal pyrites (FeS2, CoS2, NiS2) is introduced. The ALD synthesis approach allows for atomic‐precision control over film composition and thickness, excellent film uniformity and conformality, and superior process reproducibility, and therefore it is of high promise for uniformly conformal metal pyrite thin‐film coatings on complex 3D structures in general. Details and implications of this ALD approach are discussed in this Concept, mainly from a conceptual perspective, and it is envisioned that, with this new ALD synthesis approach, a significant amount of new studies will be enabled on both the fundamentals, and novel applications of the metal pyrite materials.
DNA–RNA Hybrid Quadruplexes Reveal Interactions that Favor RNA Parallel Topologies
Authors: Haase Linn , Dickerhoff Jonathan , Weisz Klaus
Published: August 2018

A DNA G‐quadruplex adopting a (3+1)‐hybrid structure was substituted at its 5′‐tetrad by riboguanosine (rG) analogs. Incorporation of anti‐favoring rG at appropriate syn‐positions of the 5′‐outer tetrad induced conformational rearrangements to yield a quadruplex featuring a 5′‐tetrad with reversed polarity. A high‐resolution structure of a disubstituted quadruplex variant as well as direct NMR experimental evidence reveals a non‐conventional C−H⋅⋅⋅O hydrogen bond in a medium groove between the 2′‐OH of an rG residue adopting a C2′‐endo sugar pucker and H8 of a 3′‐neighboring anti‐G residue. In contrast, a C3′‐endo sugar conformation for another guanine ribonucleotide prevents formation of a corresponding hydrogen bond but relocates its 2′‐OH substituent from the quadruplex narrow groove into a medium groove. Both the formation of favorable CHO hydrogen bridges and unfavorable interactions of the 2′‐hydroxyl group in a narrow groove will promote RNA folding into a parallel topology featuring all‐anti core residues and four grooves of medium size.
Multipurpose and Durable Adhesive Hydrogel Assisted by Adenine and Uracil from Ribonucleic Acid
Authors: Liu Xin , Zhang Qin , Li Kunming , Duan Lijie , Gao Guanghui
Published: August 2018

Nucleobase pairs of adenine and uracil (A‐U) from ribonucleic acid are of particular interest for various promising material properties. Herein, a novel polyacrylamide hydrogel with adhesive properties that are assisted by adenine and uracil has been designed and investigated. The incorporation of adenine and uracil enables the formation of a polyacrylamide hydrogel with remarkable adhesive behaviour with various materials including polytetrafluoroethylene (PTFE), plastics, rubber, glasses, metal, ceramics and wood. Moreover, the adhesive hydrogel can easily and directly adhere to humid biological tissues without any extra process, including heart, liver, spleen, lung, kidney, bone and muscle of mouse. More impressively, even after repeated peeling tests (10×), the AU‐mediated polyacrylamide hydrogel still exhibits excellent durable adhesion for various materials. From mechanical contact tests, the adhesion energy of the A‐U adhesive hydrogel is 47.9 J m−2, which is nearly nine times that of polyacrylamide hydrogel (5.3 J m−2). The 90° peeling strength for aluminium, titanium, silica rubbers, glasses, PTFE and hogskin is 518, 645, 445, 396, 349, and 119 N m−1, respectively. The multipurpose and durable adhesive behaviour of hydrogels assisted by adenine and uracil indicated the promise of nucleobase pairs from ribonucleic acid for the future development of adhesive materials.
Chain‐Conformation‐Directed Polymerization Cyclization for Effective Synthesis of Macrocycles in Bulk
Authors: Cao Kai , Peng Liao , Zhu Junli , Feng Anchao , Liu Dapeng , Worku Aklilu , Liu Senyang , Lin Jiaping , Yuan Jinying , Wang Xiaosong
Published: August 2018

Biological cyclization is highly efficient, and this can be attributed to the conformation of the backbone of the biopolymer. Taking advantage of metal‐coordination geometry, we developed a method for conformation‐directed polymerization cyclization through rational design of metal carbonyl monomers that could be used to produce cyclic macromolecules, even in bulk. PFpR [PFp=(PPh2(CH2)3Cp)Fe(CO)2 with the phosphine group tethered on the cyclopentadiene (Cp) ring; R=CH3 or (CH2)5CH3] was designed and synthesized for migration insertion polymerization to generate P(PFpR) with the polymer backbone containing Cp−Fe bonds. Growth of the backbone led to a cyclic conformation with close end‐to‐end distances, which facilitated the cyclization. This conformation‐directed cyclization was attributed to the piano‐stool metal‐coordination geometry of the repeating units and the low rotational barrier of the Cp−Fe bonds in the backbone. The produced macrocycles, which contain a metal carbonyl coordination structure in their backbones, are rigid, unlike many organic macrocycles. The macrocycles thus have a large excluded volume. This new type of metal carbonyl macrocycle will be of interest as a building block for supramolecular chemistry and in the exploration of novel materials.
Synthesis and Characterization of the First Tin Fluoride Borate Sn3[B3O7]F with Second Harmonic Generation Response
Authors: Schönegger Sandra , Jantz Stephan G. , Saxer Andreas , Bayarjargal Lkhamsuren , Winkler Björn , Pielnhofer Florian , Höppe Henning A. , Huppertz Hubert
Published: August 2018

The new non‐centrosymmetric tin fluoride borate Sn3[B3O7]F was synthesized hydrothermally, and was characterized by single‐crystal and powder X‐ray diffraction, vibrational spectroscopy, DFT calculations, second harmonic generation (SHG) measurements, thermogravimetry, and differential scanning calorimetry. Its SHG response is about 12 times that of quartz. The compound crystallizes in the non‐centrosymmetric orthorhombic space group Pna21 with lattice parameters a=922.4(2), b=769.8(4), and c=1221.9(6) pm (Z=4). Characteristic for the structure are isolated B3O7 moieties, consisting of two corner‐sharing BO3 units and one BO4 tetrahedron. These occupy half of the octahedral voids of a slightly distorted hexagonal closest packing of Sn2+ atoms, with [SnF]+ units in the other half of the octahedral voids. Sn3[B3O7]F is transparent over a wide spectral range with a UV cut‐off edge at about 263 nm.
Macroscopic Chiral Recognition by Calix[4]arene‐Based Host–Guest Interactions
Authors: Quan Jiaxin , Nie Guanrong , Xue Hong , Luo Li , Zhang Ruiping , Li Haibing
Published: August 2018

Chiral recognition as an intrinsic process of life, plays a crucial role in chemical systems, and further forms various architectures in the resulted functional materials. So far, relevant studies were focused on the recognition of chiral molecules. However, weak chiral interactions transformed into macroscopic recognition, for example, for chiral drug droplets, is much more crucial due to its applicability in controlling the drugs′ selective delivery and for their enantiomer separation. In this report, chiral calix[4]arene was introduced onto a surface for the selective recognition of (S)‐naproxen droplet through host–guest interactions.
A Tautoleptic Approach to Chiral Hydrogen‐Bonded Supramolecular Tubular Polymers with Large Cavity
Authors: Neniškis Algirdas , Račkauskaitė Dovilė , Shi Qixun , Robertson Aiden J. , Marsh Andrew , Ulčinas Artūras , Valiokas Ramūnas , Brown Steven P. , Wärnmark Kenneth , Orentas Edvinas
Published: August 2018

A new strategy towards tubular hydrogen‐bonded polymers based on the self‐assembly of isocytosine tautomers in orthogonal directions is proposed and experimentally verified, including by 1H fast magic‐angle spinning (MAS) solid‐state NMR. The molecular tubes obtained possess large internal diameter and tailor‐made outer functionalities rendering them potential candidates for a number of applications.
An Endogenous Reactive Oxygen Species (ROS)‐Activated Histone Deacetylase Inhibitor Prodrug for Cancer Chemotherapy
Authors: Bhagat Somnath D. , Singh Usha , Mishra Ram Kumar , Srivastava Aasheesh
Published: August 2018

Suberoylanilide hydroxamic acid (SAHA, vorinostat) is a potent small‐molecule pan‐inhibitor of histone deacetylases (HDACs) approved for treatment of cutaneous T‐cell lymphoma (CTCL). However, SAHA exhibits poor selectivity for cancer cells over noncancer cells. With an aim to improving its selectivity for cancer cells, we generated a novel SAHA prodrug (SAHA‐OBP) that is activated in the presence of hydrogen peroxide, a reactive oxygen species (ROS) known to be overexpressed in cancer cells. The high endogenous ROS content in cancer cells triggers rapid removal of the 4‐(4,4,5,5‐tetramethyl‐1,3,2‐dioxaborolan‐2‐yl)benzyl carbonyl (OBP) cap to release active SAHA. The SAHA‐OBP prodrug demonstrates selective activity against multiple cancer cell lines such as HeLa, MCF‐7, MDA‐MB‐231, and B16‐F10, while remaining benign toward noncancer cells. The downstream effects of SAHA released from SAHA‐OBP in cancer cells is the induction of apoptosis. SAHA‐OBP was also found to be effective on multicellular tumor spheroids (MCTS). The SAHA prodrug designed in this study undergoes rapid ROS‐dependent activation and imparts much‐needed selectivity to SAHA for cancer cells.
Exploration of Sulfur‐Containing Analogues for Imaging Vesicular Acetylcholine Transporter in the Brain
Authors: Luo Zonghua , Liu Hui , Jin Hongjun , Gu Jiwei , Yu Yanbo , Kaneshige Kota , Perlmutter Joel S. , Parsons Stanley M. , Tu Zhude
Published: August 2018

Sixteen new sulfur‐containing compounds targeting the vesicular acetylcholine transporter (VAChT) were synthesized and assessed for in vitro binding affinities. Enantiomers (−)‐(1‐(3‐hydroxy‐1,2,3,4‐tetrahydronaphthalen‐2‐yl)piperidin‐4‐yl)(4‐(methylthio)phenyl)methanone [(−)‐8] and (−)‐(4‐((2‐fluoroethyl)thio)phenyl)(1‐(3‐hydroxy‐1,2,3,4‐tetrahydronaph‐thalen‐2‐yl)piperidin‐4‐yl)methanone [(−)‐14 a] displayed high binding affinities, with respective Ki values of 1.4 and 2.2 nm for human VAChT, moderate and high selectivity for human VAChT over σ1 (≈13‐fold) and σ2 receptors (>420‐fold). Radiosyntheses of (−)‐[11C]8 and (−)‐[18F]14 a were achieved using conventional methods. Ex vivo autoradiography and biodistribution studies in Sprague–Dawley rats indicated that both radiotracers have the capacity to penetrate the blood–brain barrier, with high initial brain uptake at 5 min and rapid washout. The striatal region had the highest accumulation for both radiotracers. Pretreating the rats with the VAChT ligand (−)‐vesamicol decreased brain uptake for both radiotracers. Pretreating the rats with the σ1 ligand YUN‐122 (N‐(4‐benzylcyclohexyl)‐2‐(2‐fluorophenyl)acetamide) also decreased brain uptake, suggesting these two radiotracers also bind to the σ1 receptor in vivo. The microPET study of (−)‐[11C]8 in the brain of a non‐human primate showed high striatal accumulation that peaked quickly and washed out rapidly. Although preliminary results indicated these two sulfur‐containing radiotracers have high binding affinities for VAChT with rapid washout kinetics from the striatum, their σ1 receptor binding properties limit their potential as radiotracers for quantifying VAChT in vivo.
RASPELD to Perform High‐End Screening in an Academic Environment toward the Development of Cancer Therapeutics
Authors: Wolle Patrik , Weisner Jörn , Keul Marina , Landel Ina , Lategahn Jonas , Rauh Daniel
Published: August 2018

The identification of compounds for dissecting biological functions and the development of novel drug molecules are central tasks that often require screening campaigns. However, the required architecture is cost‐ and time‐intensive. Herein we describe the devices and technologies that comprise a Robotics‐Assisted Screening Platform for Efficient Ligand Discovery (RASPELD), which we set up in an academic laboratory. RASPELD provides semi‐automated high‐end screening, and it can be maintained by graduate students. We demonstrate its successful application in biochemical and cellular screens for the identification and validation of bioactive chemical entities as candidate cancer‐relevant inhibitors. Specifically, we examined the interaction between a transcription factor, Nrf2, and its key regulator, Keap1. We also examined drug‐resistant mutants of the epidermal growth factor receptor (EGFR). Screening campaigns with more than 30 000 compounds were performed in a reasonable period of time. We identified the molecule RSL6586 as a starting point for hit optimization, which is currently ongoing.
Identification of α‐Mangostin as an Agonist of Human STING
Authors: Zhang Yibo , Sun Zhen , Pei Jianwen , Luo Qinhong , Zeng Xin , Li Qinkai , Yang Zhen , Quan Junmin
Published: August 2018

The xanthone derivate 5′,6′‐dimethylxanthenone‐4‐acetic acid (DMXAA, also known as ASA404 or vadimezan) is a potent agonist of murine STING (stimulator of interferon genes), but cannot activate human STING. Herein we report that α‐mangostin, which bears the xanthone skeleton, is an agonist of human STING, but activates murine STING to a lesser extent. Biochemical and cell‐based assays indicate that α‐mangostin binds to and activates human STING, leading to activation of the downstream interferon regulatory factor (IRF) pathway and production of type I interferons. Furthermore, our studies show that α‐mangostin has the potential to repolarize human monocyte‐derived M2 macrophages to the M1 phenotype. The agonist effect of α‐mangostin in the STING pathway might account for its antitumor and antiviral activities.
Genetic access to neurons in the accessory optic system reveals a role for Sema6A in midbrain circuitry mediating motion perception
Authors: Lilley Brendan N. , Sabbah Shai , Hunyara John L. , Gribble Katherine D. , Al‐Khindi Timour , Xiong Jiali , Wu Zhuhao , Berson David M. , Kolodkin Alex L.
Published: August 2018

The accessory optic system (AOS) detects retinal image slip and reports it to the oculomotor system for reflexive image stabilization. Here, we characterize two Cre lines that permit genetic access to AOS circuits responding to vertical motion. The first (Pcdh9‐Cre) labels only one of the four subtypes of ON direction‐selective retinal ganglion cells (ON‐DS RGCs), those preferring ventral retinal motion. Their axons diverge from the optic tract just behind the chiasm and selectively innervate the medial terminal nucleus (MTN) of the AOS. Unlike most RGC subtypes examined, they survive after optic nerve crush. The second Cre‐driver line (Pdzk1ip1‐Cre) labels postsynaptic neurons in the MTN. These project predominantly to the other major terminal nucleus of the AOS, the nucleus of the optic tract (NOT). We find that the transmembrane protein semaphorin 6A (Sema6A) is required for the formation of axonal projections from the MTN to the NOT, just as it is for the retinal innervation of the MTN. These new tools permit manipulation of specific circuits in the AOS and show that Sema6A is required for establishing AOS connections in multiple locations.
Features of the structure, development, and activity of the zebrafish noradrenergic system explored in new CRISPR transgenic lines
Authors: Farrar Matthew J. , Kolkman Kristine E. , Fetcho Joseph R.
Published: August 2018

The noradrenergic (NA) system of vertebrates is implicated in learning, memory, arousal, and neuroinflammatory responses, but is difficult to access experimentally. Small and optically transparent, larval zebrafish offer the prospect of exploration of NA structure and function in an intact animal. We made multiple transgenic zebrafish lines using the CRISPR/Cas9 system to insert fluorescent reporters upstream of slc6a2, the norepinephrine transporter gene. These lines faithfully express reporters in NA cell populations, including the locus coeruleus (LC), which contains only about 14 total neurons. We used the lines in combination with two‐photon microscopy to explore the structure and projections of the NA system in the context of the columnar organization of cell types in the zebrafish hindbrain. We found robust alignment of NA projections with glutamatergic neurotransmitter stripes in some hindbrain segments, suggesting orderly relations to neuronal cell types early in life. We also quantified neurite density in the rostral spinal cord in individual larvae with as much as 100% difference in the number of LC neurons, and found no correlation between neuronal number in the LC and projection density in the rostral spinal cord. Finally, using light sheet microscopy, we performed bilateral calcium imaging of the entire LC. We found that large‐amplitude calcium responses were evident in all LC neurons and showed bilateral synchrony, whereas small‐amplitude events were more likely to show interhemispheric asynchrony, supporting the potential for targeted LC neuromodulation. Our observations and new transgenic lines set the stage for a deeper understanding of the NA system.
Neuroarchitecture of the Drosophila central complex: A catalog of nodulus and asymmetrical body neurons and a revision of the protocerebral bridge catalog
Authors: Wolff Tanya , Rubin Gerald M.
Published: August 2018

The central complex, a set of neuropils in the center of the insect brain, plays a crucial role in spatial aspects of sensory integration and motor control. Stereotyped neurons interconnect these neuropils with one another and with accessory structures. We screened over 5,000 Drosophila melanogaster GAL4 lines for expression in two neuropils, the noduli (NO) of the central complex and the asymmetrical body (AB), and used multicolor stochastic labeling to analyze the morphology, polarity, and organization of individual cells in a subset of the GAL4 lines that showed expression in these neuropils. We identified nine NO and three AB cell types and describe them here. The morphology of the NO neurons suggests that they receive input primarily in the lateral accessory lobe and send output to each of the six paired noduli. We demonstrate that the AB is a bilateral structure which exhibits asymmetry in size between the left and right bodies. We show that the AB neurons directly connect the AB to the central complex and accessory neuropils, that they target both the left and right ABs, and that one cell type preferentially innervates the right AB. We propose that the AB be considered a central complex neuropil in Drosophila. Finally, we present highly restricted GAL4 lines for most identified protocerebral bridge, NO, and AB cell types. These lines, generated using the split‐GAL4 method, will facilitate anatomical studies, behavioral assays, and physiological experiments.
Cortical projections to the two retinotopic maps of primate pulvinar are distinct
Authors: Moore Brandon , Li Keji , Kaas Jon H. , Liao Chia‐Chi , Boal Andrew M. , Mavity‐Hudson Julia , Casagrande Vivien
Published: August 2018

Comprised of at least five distinct nuclei, the pulvinar complex of primates includes two large visually driven nuclei; one in the dorsal (lateral) pulvinar and one in the ventral (inferior) pulvinar, that contain similar retinotopic representations of the contralateral visual hemifield. Both nuclei also appear to have similar connections with areas of visual cortex. Here we determined the cortical connections of these two nuclei in galagos, members of the stepsirrhine primate radiation, to see if the nuclei differed in ways that could support differences in function. Injections of different retrograde tracers in each nucleus produced similar patterns of labeled neurons, predominately in layer 6 of V1, V2, V3, MT, regions of temporal cortex, and other visual areas. More complete labeling of neurons with a modified rabies virus identified these neurons as pyramidal cells with apical dendrites extending into superficial cortical layers. Importantly, the distributions of cortical neurons projecting to each of the two nuclei were highly overlapping, but formed separate populations. Sparse populations of double‐labeled neurons were found in both V1 and V2 but were very low in number (<0.1%). Finally, the labeled cortical neurons were predominately in layer 6, and layer 5 neurons were labeled only in extrastriate areas. Terminations of pulvinar projections to area 17 was largely in superficial cortical layers, especially layer 1.
Open‐Label, Crossover Study to Determine the Pharmacokinetics of Fluticasone Furoate and Batefenterol When Administered Alone, in Combination, or Concurrently
Authors: Ambery Claire , Young Graeme , Fuller Teresa , Georgiou Alex , Ramsay David , Puri Adeep , Daley‐Yates Peter
Published: August 2018

The study aim was to investigate the pharmacokinetics of single high doses and repeated therapeutic doses of fluticasone furoate (FF) and batefenterol (BAT; a bifunctional muscarinic antagonist and β2‐agonist) administered in combination (BAT/FF) or as monotherapy. In this open‐label, 6‐period, crossover study of 48 subjects, the treatment sequences were (1) single high‐dose BAT/FF 900/300 μg followed by repeated therapeutic doses of BAT/FF 300/100 μg (once daily for 7 days); (2) single high‐dose BAT 900 μg administered concurrently with FF 300 μg; (3) single high‐dose BAT 900 μg followed by repeated therapeutic‐dose BAT 300 μg; (4) single high‐dose FF 300 μg followed by repeated therapeutic‐dose FF 100 μg; (5) single high‐dose FF 300 μg (magnesium stearate); and (6) single high‐dose FF/vilanterol 300/75 μg. Plasma FF area under the plasma drug concentration‐time curve (AUC) was reduced after single high‐dose BAT/FF versus FF alone (ratio of geometric least squares means: 0.79; 90% confidence interval: 0.75‐0.83). After repeat dosing, FF AUC at the lower therapeutic dosage was similar for BAT/FF and FF (primary endpoint; AUC geometric least squares means: 1.03). Adverse events were minor, the most common being cough. These data support the feasibility of developing BAT/inhaled corticosteroid triple therapy in a single inhaler.
Heterogeneous distributed computing based on high‐level abstractions
Authors: Viñas M. , Fraguela B. B. , Andrade D. , Doallo R.
Published: August 2018

The rise of heterogeneous systems has given place to great challenges for users as they involve new concepts, restrictions, and frameworks. Their exploitation is further complicated in the context of distributed memory systems, which require the usage of additional different programming paradigms and tools. In this paper, we propose a novel approach to program heterogeneous clusters that is based on high‐level abstractions such as tiles and hierarchical decomposition combined with the powerful APIs that data types and embedded languages can provide in languages such as C++. Rather than building our proposal from scratch, we have implemented it as a natural integration of the existing Hierarchically Tiled Arrays (HTA) and Heterogeneous Programming Library (HPL) projects, ie, the first one being focused on distributed computing and the second one on heterogeneous processing. The result, called Heterogeneous Hierarchically Tiled Arrays (H2TA), is very intuitive and easy to use thanks to the global view of the data and the single‐threaded view of the execution that it provides at cluster level together with the transparency it provides with respect to the management of the heterogeneous devices. An evaluation comparing our proposal with MPI‐based implementations shows its large programmability advantages and the reasonable overhead incurred.
A new quality assessment for Thangka image inpainting
Authors: Hu Wenjin , Liu Zhongmin , Ye Yuqi
Published: August 2018

This paper presents an efficient metric for evaluation the effect of the inpainted Thangka images. In contrast to standard image quality metrics, the proposed one takes into account some constraints and characteristics related to the specific goals of inpainting techniques. The key is that we proposed a method to decompose the reference and distorted image and to compare the intensity of fuzzy edge for structure component and similarity for texture component. By comparative analyzing the experimental results with other metrics, the proposed image inpainting quality index delivers high consistency with subjective evaluation results, which will help the selecting algorithm in image restoration and could be also applied to most of inpainting image approaches.
Ionic Liquids Derived from Proline: Application as Surfactants
Authors: Fernández‐Stefanuto Verónica , Corchero Raquel , Rodríguez‐Escontrela Iria , Soto Ana , Tojo Emilia
Published: August 2018

Ionic liquids derived from prolinium esters, previously described as fully green and stable, were found to decompose in the presence of water by ester hydrolysis. To avoid this problem, a new family of these biodegradable salts incorporating an alcohol instead of the ester group is proposed. From this family, two novel ionic liquids that incorporate the prolinolium cation [HOPro] and the [DS] or [DBS] anion were selected (DS=dodecylsulfate; DBS=dodecylbenzenesulfonate). Both salts are liquid at room temperature, a property not usually found in ionic surfactants, and are also chemically and thermally stable. Moreover, they are more effective in reducing the surface tension of water than the corresponding traditional surfactants in the form of sodium salts, being useful for applications related to their aggregation capacity. They were tested for surfactant enhanced oil recovery and an optimal formulation for reservoirs at high salinity and temperature, able to produce ultra‐low interfacial tension, was found with [HOPro][DBS].
Theoretical Study on Open‐Shell Singlet Character and Second Hyperpolarizabilities in Cofacial π‐Stacked Dimers Composed of Weak Open‐Shell Antiaromatic Porphyrins
Authors: Fujiyoshi Jun‐Ya , Tonami Takayoshi , Yamane Masaki , Okada Kenji , Kishi Ryohei , Muhammad Shabbir , Al‐Sehemi Abdullah G. , Nozawa Ryo , Shinokubo Hiroshi , Nakano Masayoshi
Published: August 2018

From the analysis based on the broken‐symmetry density functional theory (DFT) calculations, we in this study propose a strategy to enhance the open‐shell characters and third‐order nonlinear optical (NLO) properties of π‐stacked dimers composed of antiaromatic molecules with weak open‐shell characters. For this purpose, we here constructed cofacial π‐stacked dimer models composed of aromatic and antiaromatic NiII porphyrins in order to examine the π‐π stacking distance (R) dependence of the diradical characters (y) and static second hyperpolarizabilities (γ). The antiaromatic porphyrin dimers are found to have intermediate y around R∼3.3 Å, the result of which originates in the unique intermolecular interactions between the antiaromatic monomers. Static γ along the stacking direction of such antiaromatic porphyrin dimers with intermediate diradical characters are shown to be enhanced significantly as compared to those of the isolated monomers and the aromatic porphyrin dimers.
Pulsed Electrodeposition of Co3O4 Nanocrystals on One‐Dimensional ZnO Scaffolds for Enhanced Electrochemical Water Oxidation
Authors: Wu Hao , Li Shangyi , Lu Xinxin , Toe Cui Ying , Chung Hoi Ying , Tang Yiming , Lu Xunyu , Amal Rose , Li Laisheng , Ng Yun Hau
Published: August 2018

Pulsed electrodeposition has been introduced to deposit ultrathin flakes of Co3O4 nanocrystals on ZnO nanorods. By fixing the seeding process, the scaffolding function of ZnO nanorods was studied by varying deposition times (30 s, 60 s, and 90 s) of Co3O4 at a nucleation current of −1.0 mA cm−2. The amount of deposited Co3O4 has a strong influence on the oxygen evolution performance with ZnO scaffolds. To deliver a current density of 10.0 mA cm−2 in neutral solutions (0.5 M K2SO4), the presence of ZnO scaffold electrodes negatively shifted the overpotential by ∼200 mV. In particular, the Co3O4/ZnO hybrid nanostructured electrode (60 s) exhibits the lowest onset potential of 1.5 V (vs. reversible hydrogen electrode, RHE). Electrochemical impedance spectra and double layer capacitance showed that the enhanced oxygen evolution activities originated from the improved charge transfer capability and the increased electrochemically active interface between Co3O4 and ZnO.
[4]Cyclofluorene: Unexpected Influence of Alkyl Chain Length
Authors: Sicard Lambert , Jeannin Olivier , Rault‐Berthelot Joëlle , Quinton Cassandre , Poriel Cyril
Published: August 2018

Presented here is the study of a new example of [4]cyclofluorene, with ethyl chains on the bridgeheads. Its molecular structure was established by solution NMR spectroscopy and single‐crystal X‐ray diffraction. Three successive oxidation processes and one reversible reduction were observed through cyclic voltammetry. The optical properties were characterized both in solution and thin film by UV/visible spectroscopy as well as stationary and time‐resolved fluorescence. It was found that this [4]cyclofluorene displays different characteristics compared with the other [4]cyclofluorenes substituted by methyl or propyl chains: a simple modification of the chain length induces a non‐negligible effect on the emission properties, which must be linked to the specific arrangement of the fluorene units. Furthermore, single‐crystal X‐ray diffraction reveals the formation of a pseudo‐tubular solid‐state arrangement of fully symmetrical ring structures, which was not observed for the other members of the [4]cyclofluorenes family. This finding could open the way to modulation of properties of cyclofluorenes through alkyl chain engineering.
A Prospective International Study on Adherence to Treatment in 305 Patients With Flaring SLE: Assessment by Drug Levels and Self‐Administered Questionnaires
Authors: Costedoat‐Chalumeau Nathalie , Houssiau Frédéric , Izmirly Peter , Guern Véronique Le , Navarra Sandra , Jolly Meenakshi , Ruiz‐Irastorza Guillermo , Baron Gabriel , Hachulla Eric , Agmon‐Levin Nancy , Shoenfeld Yehuda , Dall'Ara Francesca , Buyon Jill , Deligny Christophe , Cervera Ricard , Lazaro Estibaliz , Bezanahary Holy , Leroux Gaëlle , Morel Nathalie , Viallard Jean‐François , Pineau Christian , Galicier Lionel , Vollenhoven Ronald Van , Tincani Angela , Nguyen Hanh , Gondran Guillaume , Zahr Noel , Pouchot Jacques , Piette Jean‐Charles , Petri Michelle , Isenberg David
Published: August 2018

Nonadherence to treatment is a major cause of lupus flares. Hydroxychloroquine (HCQ), a major medication in systemic lupus erythematosus, has a long half‐life and can be quantified by high‐performance liquid chromatography. This international study evaluated nonadherence in 305 lupus patients with flares using drug levels (HCQ < 200 ng/ml or undetectable desethylchloroquine), and self‐administered questionnaires (MASRI < 80%). Drug levels defined 18.4% of the patients as severely nonadherent. In multivariate analyses, younger age, nonuse of steroids, higher body mass index, and unemployment were associated with nonadherence by drug level. Questionnaires classified 23.4% of patients as nonadherent. Correlations between adherence measured by questionnaires, drug level, and physician assessment were moderate. Both methods probably measured two different patterns of nonadherence: self‐administered questionnaires mostly captured relatively infrequently missed tablets, while drug levels identified severe nonadherence (i.e., interruption or erratic tablet intake). The frequency with which physicians miss nonadherence, together with underreporting by patients, suggests that therapeutic drug monitoring is useful in this setting. (Trial registration: ClinicalTrials.gov: NCT01509989.)