bluuebunny/crossref_metadata_2025 huggingface dataset:
Microstructure, Micro‐Hardness, and Corrosion Resistance of Commercial Purity Al Processed by Hollow‐Cone High‐Pressure Torsion
Authors: Guo Jing , Zhang Xiaorong , Kong Dan , Joo Soo‐Hyun , Kim Wooyeol , Kim Hyoung Seop , Zhang Xiaohui
Published: December 2018

Hollow‐cone high‐purity commercial Al prepared using copper mold suction casting method is annealed at 600 °C, then processed by high‐pressure torsion of 0.25 and 0.5 revolutions to produce ultrafine‐grained materials. Microstructure, micro‐hardness, and corrosion resistance in 3.5% NaCl solution are investigated in this paper. The grain size of the deformed Al after 0.25 and 0.5 revolutions are 1.16 and 0.73 µm, respectively, which are smaller than that of the annealed specimen of 33.46 µm determined using electron backscatter diffraction. The micro‐hardness of the deformed Al is two‐times larger than that of the annealed specimen. In addition, corrosion resistance of the deformed Al is higher than that of the annealed specimen, which is verified by polarization tests and scanning electron microscopy.
Full 3D Printing of Stretchable Piezoresistive Sensor with Hierarchical Porosity and Multimodulus Architecture
Authors: Wang Ziya , Guan Xiao , Huang Huayi , Wang Haifei , Lin Waner , Peng Zhengchun
Published: December 2018

A soft piezoresistive sensor with its unique characteristics, such as human skin, light weight, and multiple functions, yields a variety of possible practical applications to skin‐attachable electronics, human–machine interfaces, and electronic skins. However, conventional filler‐matrix piezoresistive sensors often suffer from unsatisfactory sensitivity or insufficient measurement range, as well as significant cross‐correlation between out‐of‐plane pressure and in‐plane extension. Here, a stretchable piezoresistive sensor (SPS) is realized by combining a hierarchically porous sensing element with a multimodulus device architecture via a full 3D printing process. As a result, the sensor exhibits high sensitivity (5.54 kPa−1), large measurement range (from 10 Pa to 800 kPa), limited cross‐correlation, and excellent durability. Meanwhile, benefiting from the porous structure and mechanical mismatch design, which efficiently distributes the stress away from the sensing element, the device experiences only 7% resistance change at 50% stretching. This approach is employed to rapidly program and readily manufacture stylish, all‐in‐one, functional devices for various applications, demonstrating that the technique is promising for customized stretchable electronics.
Triboiontronic Transistor of MoS2
Authors: Gao Guoyun , Yu Jinran , Yang Xixi , Pang Yaokun , Zhao Jing , Pan Caofeng , Sun Qijun , Wang Zhong Lin
Published: December 2018

Electric double layers (EDLs) formed in electrolyte‐gated field‐effect transistors (FETs) induce an extremely large local electric field that gives a highly efficient charge carrier control in the semiconductor channel. To achieve highly efficient triboelectric potential gating on the FET and explore diversified applications of electric double layer FETs (EDL‐FETs), a triboiontronic transistor is proposed to bridge triboelectric potential modulation and ion‐controlled semiconductor devices. Utilizing the triboelectric potential instead of applying an external gate voltage, the triboiontronic MoS2 transistor is efficiently operated owing to the formation of EDLs in the ion‐gel dielectric layer. The operation mechanism of the triboiontronic transistor is proposed, and high current on/off ratio over 107, low threshold value (75 μm), and steep switching properties (20 µm dec−1) are achieved. A triboiontronic logic inverter with desirable gain (8.3 V mm−1), low power consumption, and high stability is also demonstrated. This work presents a low‐power‐consuming, active, and a general approach to efficiently modulate semiconductor devices through mechanical instructions, which has great potential in human–machine interaction, electronic skin, and intelligent wearable devices. The proposed triboiontronics utilize ion migration and arrangement triggered by mechanical stimuli to control electronic properties, which are ready to deliver new interdisciplinary research directions.
Mass‐Manufactural Lanthanide‐Based Ultraviolet B Microlasers
Authors: Jin Limin , Wu Yunkai , Wang Yujie , Liu Shuai , Zhang Yuqi , Li Zhiying , Chen Xian , Zhang Wenfei , Xiao Shumin , Song Qinghai
Published: December 2018

Lanthanide (Ln3+)‐based ultraviolet B (UVB) microlasers are highly desirable for diagnostics and phototherapy. Despite their progress, the potential applications of UVB microlasers are strongly hindered by their low optical gain, weak light confinements, and poor device repeatability. Herein, a novel all‐in‐one approach to solve the above limitations and realize mass‐manufactural UVB microlasers is reported. The gain coefficient at 289 nm is improved from two aspects, i.e., the enhanced absorption via LiYbF4:Tm(1mol%)@LiYbF4@LiLuF4 core–shell–shell nanocrystals and the suppression of competitive ultraviolet emissions. Consequently, by spin‐coating the solution onto a patterned SiO2 substrate, high‐quality Ln3+‐based microdisks are formed by self‐assembly on each SiO2 pillar and UVB whispering‐gallery‐mode lasers are realized. The resulted lasing threshold is an order of magnitude smaller than the shortest deep‐ultraviolet emission at 310.5 nm. Importantly, the lasing wavelengths and mode numbers of UVB lasers are highly controllable and repeatable, making them suitable for mass production for the first time.
Intramolecular and Ferrier Rearrangement Strategy for the Construction of C1‐β‐d‐xylopyranosides: Synthesis, Mechanism and Biological Activity Study
Authors: Yao Yuan , Xiong Cai‐Ping , Zhong Ya‐Ling , Bian Guo‐Wei , Huang Nian‐Yu , Wang Long , Zou Kun
Published: December 2018

A stereoselective synthesis of C1‐β‐d‐xylopyranoside derivatives had been developed via intramolecular 1,3‐acyloxy migration/Ferrier rearrangement stategy from readily available propargylic carboxylates and d‐xylal. A combined catalytic system of chloro(triphenylphosphine)gold(I) (Ph3PAuCl) and silver hexafluoroantimonate (AgSbF6) was found to possess the most effective of the reaction, and 20 examples tested the wide functional compatibility for these transformation. Nuclear magnetic resonance (NMR), infrared spectrum (IR), high resolution electrospray ionization mass spectroscopy (HRESIMS) and isotopic labelling experiments were utilized to investigate the C1‐glycosylation process. The relative configuration for the products was determined by two‐dimensional (2D) NMR NMR and electronic circular dichroism spectroscopy. 3‐(4,5)‐Dimethylthiahiazo(‐z‐y1)‐3,5‐diphenytetrazoliumro‐mide (MTT) cell viability assays indicated that three of them showed strong anti‐proliferative activities against human gastric cancer HGC‐27 cells with IC50 values of 17.09‐38.88 μM. This method opened up new horizons for the synthesis of bioactive C‐glycosylated molecules.

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Chemoselectivity Switching in the Rhodium‐Catalyzed Reactions of 4‐Substituted‐1‐sulfonyl‐1,2,3‐triazoles with Allenols: Noticeable Differences between 4‐Acyl‐ and 4‐Aryl‐Triazoles
Authors: Alcaide Benito , Almendros Pedro , Fernández Israel , del Campo Teresa Martínez , Palop Guillermo , Toledano‐Pinedo Mireia , Delgado‐Martínez Patricia
Published: December 2018

Tunable chemoselectivity (O‐ versus C‐attack) in the rhodium‐catalyzed reactions of allenols with 4‐substituted‐1‐sulfonyl‐1,2,3‐triazoles has been achieved through the replacement of the 4‐aryl substituent by a 4‐acetyl moiety.

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Catalyst‐Free Sulfonylation of (Hetero)aryl Iodides with Sodium Dithionite
Authors: Li Yuewen , Liu Tong , Qiu Guanyinsheng , Wu Jie
Published: December 2018

The commercially available and cheap sodium dithionite is used as the source of sulfonyl group for the synthesis of sulfones and sulfonamides from (hetero)aryl iodides under catalyst‐free conditions. During the reaction process, sodium sulfinates generated in situ are the key intermediate, which can be further converted into diverse sulfones and sulfonamides. This transformation proceeds through a radical process initiated by sodium dithionite, providing a convenient route to sulfonyl‐containing compounds.

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2‐Alkynylaryl Aldehydes (Enynals) in Organic Synthesis
Authors: Li Longlong , Huang Dayun , Shi Chengjin , Yan Guobing
Published: December 2018

2‐Alkynylaryl aldehydes are widely used in organic reactions. Their great success is rooted in their multiple functional groups. This review will focus on five kinds of triggered mechanisms: (i) aldehydes as electrophiles, (ii) alkynes as electrophiles, (iii) 5‐exo‐dig reactions, (iv) 6‐endo‐dig intermediates, and (v) imine intermediates via 6‐endo‐dig cyclizations. Reactions with alkenes, alkynes, arenes, malononitrile, alcohols, amines, amides, acetal, ketones, hydrazine, iodobenzene, azides, carbenes, arylboronic acids, amino acids etc. will be discussed. We hope that this review will pronote future research in this area.

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Germany and Climate Protection: From Model Pupil to Laggard—Why Coal Phasing Out Makes Economic and Ecological Sense
Authors: Kemfert Claudia
Published: December 2018

Germany has gone from being a pioneer to a laggard when it comes to climate protection. The proportion of Germany's most polluting energy source, lignite, is higher than ever before. Renewable energies are being thwarted. There is no sustainable transport policy that focuses on traffic avoidance, relocation, and electrification as well as environmental, climate, and health protection—not even after the diesel scandal. The climate protection targets that are set are missed. A clever energy transition is different. Germany will only be able to regain its credibility as a climate protection world champion if the phase‐out of coal is initiated today and completed in a decade, a sustainable transition in transport is initiated and the entire energy system is converted to renewable energies. This creates enormous economic opportunities for a long overdue modernization of the German economy.
The Nitromethylation of 1,3‐Diarylpropenes Mediated by DDQ: N,N‐Dimethyl‐2‐Nitroethyleneamine as a Nitromethane Equivalent
Authors: Deng Zhiteng , Cheng Dongping , Xu Xiaoliang , Yan Jizhong
Published: December 2018

The nitromethylation of 1,3‐diarylpropenes via 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ) mediated C−H oxidative activation is reported, in which N,N‐dimethyl‐2‐nitroethyleneamine is used as a nitromethane equivalent. The precedent method for the synthesis of 1,3‐diaryl‐2‐propenylnitromethanes is safe and easy to work‐up.
Oligomerization, Isomerization and Carboxylation of Alkanes and Alkenes with Galvanostatically Generated Superoxide in the Al/O2 Electrochemical Cell
Authors: Al Sadat Wajdi I. , Archer Lynden A.
Published: December 2018

Conversion of low‐value, but thermodynamically stable chemical byproducts such as alkanes or CO2 to more valuable feedstocks is of broad‐based interest. These so‐called up‐conversion processes are expensive because they require energy‐intensive and catalytic interventions to drive reactions against thermodynamic gradients. Here we show that the nucleophilic characteristics of superoxides, generated galvanostatically in an Aluminum/O2 electrochemical cell, can be used in tandem with the intrinsic catalytic properties of an imidazolium/AlCl3 electrolyte to facilely upgrade alkanes (n‐decane), alkenes (1‐decene), and CO2 feedstocks. The aluminum/O2 electrochemical cell used to generate the superoxide intermediate is also reported to deliver large amounts of electrical energy and therefore offers a system for high‐energy density storage and for chemical up‐conversion of low‐value compounds. Chronopotentiometry, mass spectrometry and nuclear magnetic resonance were used to investigate the electrochemical features of the system and to analyze the discharge products. We find that even at room temperature, alkanes and alkenes are facilely oligomerized and isomerized at high conversions (>97 %), mimicking the traditionally produced refined products. Incorporating CO2 in the alkane feed leads to formation of esters and formates at moderate yields (21 %).
Ortsaufgelöste Beobachtung von Schwingungsenergietransfer durch ein genetisch codiertes ultraschnelles Heizelement
Authors: Baumann Tobias , Hauf Matthias , Schildhauer Fabian , Eberl Katharina B. , Durkin Patrick M. , Deniz Erhan , Löffler Jan G. , Acevedo‐Rocha Carlos G. , Jaric Jelena , Martins Berta M. , Dobbek Holger , Bredenbeck Jens , Budisa Nediljko
Published: December 2018

Eine Reihe theoretischer Studien setzt allosterischen Informationstransfer in Proteinen in Beziehung zu definierten Schwingungsenergietransfer(VET)‐Pfaden. Experimentelle Evidenz für diese Pfade ist rar, da für ihre Erforschung eine punktuelle Injektion von Schwingungsenergie in Proteine, d. h. eine lokale Erhitzung, benötigt wird. Um diese Experimente zu ermöglichen, haben wir den ortsspezifischen Einbau der nichtkanonischen Aminosäure β‐(1‐Azulenyl)‐l‐alanin (AzAla) mithilfe des erweiterten genetischen Codes etabliert. AzAla stellt eine Ausnahme der Kasha‐Regel dar: während die Aminosäure bei S1‐Anregung interne Konversion durchläuft und dadurch erhitzt, kann sie bei S2‐Anregung als Fluoreszenzmarker dienen. Wir haben PDZ3, eine Interaktionsdomäne des postsynaptischen Proteins PSD‐95, an verschiedenen Positionen mit diesem ultraschnellen Heizelement ausgestattet. Unter Verwendung von ultraschneller IR‐Spektroskopie konnten wir VET, ausgehend von AzAla innerhalb des Proteins, zu einem gebundenen Liganden auf einer Pikosekunden‐Zeitskala beobachten. Dieser Ansatz basierend auf dem genetisch codierten Einbau von AzAla ebnet den Weg zu detaillierten Studien von VET und seiner Funktion in einer Vielzahl von Proteinen.
Tracking the Process of a Solvothermal Domino Reaction Leading to a Stable Triheteroarylmethyl Radical: A Combined Crystallographic and Mass‐Spectrometric Study
Authors: Liu Bin , Yu Fei , Tu Min , Zhu Zhong‐Hong , Zhang Yuexing , Ouyang Zhong‐Wen , Wang Zhenxing , Zeng Ming‐Hua
Published: December 2018

A new free carbon radical was obtained in a microwave‐assisted solvothermal reaction of the primary amine (1‐methyl‐1H‐benzo[d]imidazol‐2‐yl)methanamine with FeCl3⋅6 H2O in methanol at 140 °C. Through a combination of crystallography and electrospray ionization mass spectrometry, the reaction process was studied. The longest domino reaction includes 14 steps and forms up to 12 new covalent bonds (9 C−N and 3 C−C bonds) and 3 five‐membered heterocycles. For the first time, the homolytic cleavage of a C−O bond was used to synthesize a triarylmethyl radical.
Freezing‐directed Stretching and Alignment of DNA Oligonucleotides
Authors: Liu Biwu , Wu Tianyi , Huang Zhicheng , Liu Yibo , Liu Juewen
Published: December 2018

Most single‐stranded DNA oligonucleotides are random coils with a persistence length of below 1 nm. So far, no good methods are available to stretch oligonucleotides. Herein, it is shown that freezing can stretch DNA, as confirmed using fluorescence resonance energy transfer, thiazole‐orange staining, and surface‐enhanced Raman spectroscopy. Lateral inter‐strand interactions are critical, and the stretched DNA oligonucleotides are aligned. This work also provides a set of methods for studying frozen oligonucleotides. Upon freezing, DNA oligonucleotides are readily adsorbed onto various nanomaterials, including gold nanoparticles, graphene oxide, iron oxide, and WS2 via the most thermodynamically stable conformation, leading to more stable conjugates.
An Activity‐Based Probe Targeting Non‐Catalytic, Highly Conserved Amino Acid Residues within Bromodomains
Authors: D'Ascenzio Melissa , Pugh Kathryn M. , Konietzny Rebecca , Berridge Georgina , Tallant Cynthia , Hashem Shaima , Monteiro Octovia , Thomas Jason R. , Schirle Markus , Knapp Stefan , Marsden Brian , Fedorov Oleg , Bountra Chas , Kessler Benedikt M. , Brennan Paul E.
Published: December 2018

Bromodomain‐containing proteins are epigenetic modulators involved in a wide range of cellular processes, from recruitment of transcription factors to pathological disruption of gene regulation and cancer development. Since the druggability of these acetyl‐lysine reader domains was established, efforts were made to develop potent and selective inhibitors across the entire family. Here we report the development of a small molecule‐based approach to covalently modify recombinant and endogenous bromodomain‐containing proteins by targeting a conserved lysine and a tyrosine residue in the variable ZA or BC loops. Moreover, the addition of a reporter tag allowed in‐gel visualization and pull‐down of the desired bromodomains.
Controlling Interfacial Charge Transfer and Fill Factors in CuO‐based Tandem Dye‐Sensitized Solar Cells
Authors: Langmar Oliver , Fazio Ettore , Schol Peter , de la Torre Gema , Costa Rubén D. , Torres Tomás , Guldi Dirk M.
Published: December 2018

We designed and synthesized a series of novel electron‐accepting zinc(II)phthalocyanines (ZnPc) and probed them in p‐type dye sensitized solar cells (p‐DSSCs) by using CuO as photocathodes. By realizing the right balance between interfacial charge separation and charge recombination, optimized fill factors (FFs) of 0.43 were obtained. With a control over fill factors in p‐DSSCs in hand we turned our attemtion to t‐DSSCs, in which we combined for the first time CuO‐based p‐DSSCs with TiO2‐based n‐DSSCs using ZnPc and N719. In the resulting t‐DSSCs, the VOC of 0.86 V is the sum of those found in p‐ and n‐DSSCs, while the FF remains around 0.63. It is only the smaller Jscs in t‐DSSCs that limits the efficiency to 0.69 %.
Lithiophilic Faceted Cu(100) Surfaces: High Utilization of Host Surface and Cavities for Lithium Metal Anodes
Authors: Gu Yu , Xu Hong‐Yu , Zhang Xia‐Guang , Wang Wei‐Wei , He Jun‐Wu , Tang Shuai , Yan Jia‐Wei , Wu De‐Yin , Zheng Ming‐Sen , Dong Quan‐Feng , Mao Bing‐Wei
Published: December 2018

Lithium metal anodes suffer from poor cycling stability and potential safety hazards. To alleviate these problems, Li thin‐film anodes prepared on current collectors (CCs) and Li‐free types of anodes that involve direct Li plating on CCs have received increasing attention. In this study, the atomic‐scale design of Cu‐CC surface lithiophilicity based on surface lattice matching of the bcc Li(110) and fcc Cu(100) faces as well as electrochemical achievement of Cu(100)‐preferred surfaces for smooth Li deposition with a low nucleation barrier is reported. Additionally, a purposely designed solid–electrolyte interphase is created for Li anodes prepared on CCs. Not only is a smooth planar Li thin film prepared, but a uniform Li plating/stripping on the skeleton of 3D CCs is achieved as well by high utilization of the surface and cavities of the 3D CCs. This work demonstrates surface electrochemistry approaches to construct stable Li metal–electrolyte interphases towards practical applications of Li anodes prepared on CCs.
Precise In Vivo Inflammation Imaging Using In Situ Responsive Cross‐linking of Glutathione‐Modified Ultra‐Small NIR‐II Lanthanide Nanoparticles
Authors: Zhao Mengyao , Wang Rui , Li Benhao , Fan Yong , Wu Yifan , Zhu Xinyan , Zhang Fan
Published: December 2018

To improve the bioimaging signal‐to‐noise ratio (SNR), long‐term imaging capability, and decrease the potential biotoxicity, an in vivo cross‐linking strategy was developed by using sub‐10 nm, glutathione‐modified, lanthanide nanoprobes. After administration, the nanoprobes cross‐link in response to reactive oxygen species (ROS) at the inflamed area and enable the quick imaging of ROS in the second near‐infrared (NIR‐II) window. These nanoprobes could be rapidly excreted due to their ultra‐small size. This strategy may also be applied to other ultra‐small contrast agents for the precise bioimaging by in situ lesion cross‐linking.
Site‐Resolved Observation of Vibrational Energy Transfer Using a Genetically Encoded Ultrafast Heater
Authors: Baumann Tobias , Hauf Matthias , Schildhauer Fabian , Eberl Katharina B. , Durkin Patrick M. , Deniz Erhan , Löffler Jan G. , Acevedo‐Rocha Carlos G. , Jaric Jelena , Martins Berta M. , Dobbek Holger , Bredenbeck Jens , Budisa Nediljko
Published: December 2018

Allosteric information transfer in proteins has been linked to distinct vibrational energy transfer (VET) pathways in a number of theoretical studies. Experimental evidence for such pathways, however, is sparse because site‐selective injection of vibrational energy into a protein, that is, localized heating, is required for their investigation. Here, we solved this problem by the site‐specific incorporation of the non‐canonical amino acid β‐(1‐azulenyl)‐l‐alanine (AzAla) through genetic code expansion. As an exception to Kasha's rule, AzAla undergoes ultrafast internal conversion and heating after S1 excitation while upon S2 excitation, it serves as a fluorescent label. We equipped PDZ3, a protein interaction domain of postsynaptic density protein 95, with this ultrafast heater at two distinct positions. We indeed observed VET from the incorporation sites in the protein to a bound peptide ligand on the picosecond timescale by ultrafast IR spectroscopy. This approach based on genetically encoded AzAla paves the way for detailed studies of VET and its role in a wide range of proteins.
PdII‐Catalyzed Regio‐ and Enantioselective Oxidative C−H/C−H Cross‐Coupling Reaction between Ferrocenes and Azoles
Authors: Cai Zhong‐Jian , Liu Chen‐Xu , Gu Qing , Zheng Chao , You Shu‐Li
Published: December 2018

Asymmetric C−H bond functionalization reaction is one of the most efficient and straightforward methods for the synthesis of optically active molecules. Herein we disclose an asymmetric C−H/C−H cross‐coupling reaction of ferrocenes with azoles such as oxazoles and thiazoles. Palladium(II)/monoprotected amino acid (MPAA) catalytic system which exhibits excellent reactivity and regioselectivity for oxazoles and thiazoles. This method offers a powerful strategy for constructing planar chiral ferrocenes. Mechanistic studies suggest that the C−H bond cleavage of azoles is likely proceeding through a SEAr process and may not be a turnover limiting step.
A Bioethos for Bodies: Respecting a Priceless Resource
Authors: Champney Thomas H.
Published: December 2018

The value that willed body donors provide to medical education is priceless. Their precious gift helps to teach anatomy, spatial relationships between morphological structures, anatomical variation, and professionalism to medical students in a way that plastic models, podcasts, and lectures cannot. They are also an important resource for medical research and a wide variety of postgraduate training opportunities. While many body donation programs throughout the world are nonprofit organizations, there are body donation companies in the United States that sell donors for‐profit. These “body brokers” have accumulated large profits from this business. It is incongruous that others would profit from such a priceless, freely donated gift. To prevent this incongruity, it is proposed that the international anatomical community develop a normative culture (a bioethos) for body donation programs. This would involve the conscious and systematic development of ethical principles for the day‐to‐day policies and practices of institutions that collect and use human bodies. With the development of this bioethos, a cultural shift in how donors are treated would occur and, over time, this would become the normal practice. These principles would become fundamental and foundational for the procurement and use of priceless human tissues.
Impact of tetramerization on the ligand recognition of N1 influenza neuraminidase via MMGBSA approach
Authors: Bello Martiniano
Published: December 2018

Influenza virus neuraminidase (NA) is a homotetrameric surface protein that, in contrast to other non‐influenza NAs, requires a quaternary assembly to exhibit enzymatic activity, suggesting that the oligomeric state significantly impacts the active site of influenza NA. Nevertheless, most structure‐based drug design studies have been reported by employing the monomeric state in the closed or open‐loop due to the computational cost of employing the tetrameric NA. In this work, we present MD simulations coupled to the MMGBSA approach of avian N1 type NA in its monomeric and tetrameric closed and open‐loop state both with and without the inhibitor oseltamivir and its natural substrate, sialic acid. Structural and energetic analyses revealed that the tetrameric state impacts flexibility as well as the map of interactions participating in stabilizing the protein–ligand complexes with respect to the monomeric state. It was observed that the tetrameric state exerts dissimilar effects in binding affinity, characteristic of positive and negative cooperativity for oseltamivir and sialic acid, respectively. Based on our results, to perform a confident structure‐based drug design, as well as to evaluate the impact of key mutations through MD simulations, it is important to consider the tetrameric state closed‐loop state.
Smart Design of Small‐Molecule Libraries: When Organic Synthesis Meets Cheminformatics
Authors: Lenci Elena , Trabocchi Andrea
Published: December 2018

Synthetic chemists are always looking for new methods to maximize the diversity and complexity of small‐molecule libraries. Diversity‐oriented synthesis can give access to new chemotypes with high chemical diversity, exploiting complexity‐generating reactions and divergent approaches. However, there is a need for new tools to drive synthetic efforts towards unexplored and biologically relevant regions of chemical space. Because the number of publicly accessible biological data will increase in the years to come, cheminformatics can represent a real opportunity to develop better chemical libraries. This minireview focuses on novel cheminformatics approaches used to design molecular scaffolds, as well as to analyze their quality, giving a perspective of them in the field of chemical biology and drug discovery through some selected case studies.
Identifying the Biosynthetic Gene Cluster for Triacsins with an N‐Hydroxytriazene Moiety
Authors: Twigg Frederick F. , Cai Wenlong , Huang Wei , Liu Joyce , Sato Michio , Perez Tynan J. , Geng Jiaxin , Dror Moriel J. , Montanez Ismael , Tong Tate L. , Lee Hyunsu , Zhang Wenjun
Published: December 2018

Triacsins are a family of natural products having in common an N‐hydroxytriazene moiety not found in any other known secondary metabolites. Though many studies have examined the biological activity of triacsins in lipid metabolism, their biosynthesis has remained unknown. Here we report the identification of the triacsin biosynthetic gene cluster in Streptomyces aureofaciens ATCC 31442. Bioinformatic analysis of the gene cluster led to the discovery of the tacrolimus producer Streptomyces tsukubaensis NRRL 18488 as a new triacsin producer. In addition to targeted gene disruption to identify necessary genes for triacsin production, stable isotope feeding was performed in vivo to advance the understanding of N‐hydroxytriazene biosynthesis.
Sintering and Coke Resistant Core/Yolk Shell Catalyst for Hydrocarbon Reforming
Authors: Li Ziwei , Wang Zhigang , Kawi Sibudjing
Published: December 2018

Syngas/hydrogen production via hydrocarbon reforming reactions is crucial. Whereas, they need high reaction temperature to obtain economically feasible hydrocarbon conversions, which renders the active and cheap transition metal based catalysts easy to be sintered, leading to the high carbon deposition rate and gradual degradation of catalytic performance. Therefore, developing sintering and carbon resistant catalysts becomes one of the most important issues for these reforming reactions to be industrially applied. Designing catalysts with core/yolk shell structure turns out to be one of the most effective strategies to solve this issue. Herein, recent progress which has been made in the synthesis method for core/yolk shell catalysts with different shell materials such as SiO2, zeolite, CeO2 and Al2O3 is summarized. Additionally, specific applications of these core/yolk catalysts for various hydrocarbon reforming reactions such as dry reforming, steam reforming and methane oxidation are reviewed with the emphasis on revealing the reasons leading to their outstanding catalytic performance. Lastly, possible research directions in core/yolk shell catalysts are proposed.
Enhanced Oxygen Reduction Activity on Carbon Supported Pd Nanoparticles Via SiO2
Authors: Bao Zhikang , Zhou Hu , Song Xin , Gao Yijing , Zhuang Guilin , Deng Shengwei , Wei Zhongzhe , Zhong Xing , Wang Jianguo
Published: December 2018

To improve Pd‐based catalysts activity and stability is still challenge although Pd‐based catalysts have attracted attention for oxygen reduction reaction (ORR) during recent years. In this study, we have prepared supported Pd on SiO2, in which conductive carbon was used by coprecipitation method Pd/SiO2@C or physically mixed Pd/SiO2.Pd/SiO2@C (10 wt%) owned more outstanding catalytic activity, preferable durability, and stronger methanol tolerance capability in alkaline solution for ORR, which compared with commercial Pt/C (20 wt%) and Pd/C catalysts. We analyzed the morphology and electronic properties of the catalyst by SEM, TEM, XRD and XPS. It was found that the introduction of SiO2 changed the electronic structure of palladium, resulting in the production of electron‐rich Pd NPs, which was further confirmed by density functional theory calculations. Therefore, the introducing a small amount of SiO2 plays a vital role in facilitating the ORR activity of Pd‐based catalysts, which may be a new strategy to design new ORR catalysts and replace Pt‐based catalysts in fuel.
Electrochemical Abatement of Analgesic Antipyretic 4‐Aminophenazone using Conductive Boron‐Doped Diamond and Sub‐Stoichiometric Titanium Oxide Anodes: Kinetics, Mineralization and Toxicity Assessment
Authors: Ganiyu Soliu O. , Oturan Nihal , Trellu Clément , Raffy Stéphane , Cretin Marc , Causserand Christel , Oturan Mehmet A.
Published: December 2018

The oxidation ability of two prominent eco‐friendly electrochemical advanced oxidation processes (EAOPs), namely anodic oxidation with H2O2 generation (AO‐H2O2) and electro‐Fenton (EF) for complete abatement of acidic solution of 4‐aminophenazone (4‐APZ) has been investigated using conductive boron‐doped diamond (BDD) and sub‐stoichiometric titanium oxide (Ti4O7) anodes and carbon‐felt cathode. The higher performance of EF compared to AO‐H2O2 with either anode was demonstrated. In all trials, 4‐APZ was completely destroyed, following pseudo first‐order kinetics with the rate constant values increasing with applied current and higher values attained with BDD compared to Ti4O7 anode at similar conditions. The absolute rate constant for the reaction between 4‐APZ and hydroxyl radicals was found to be 3.9±0.2×109 L mol−1 s−1. Complete mineralization could be attained with BDD anode, whereas Ti4O7 anode only showed excellent mineralization up to 94 % TOC removal. Therefore, Ti4O7 anode can constitutes a promising anode material thanks to its lower manufacturing cost. Inorganic ions like NO3− and HCO3− at concentration up to 25 mM has no effect on mineralization efficiency during AO‐H2O2, but the presence of Cl− even at lower concentration of 10 mM significantly reduced the TOC removal efficiency. The toxicity of the solution sharply increased at initial stage of treatment, corresponding to the formation of cyclic by‐products but their conversion to carboxylic acids due to longer treatment time involved a sharp toxicity decrease, thus ensuring overall detoxification.
Synthesis of All Stereoisomers of RK460 and Evaluation of Their Activity and Selectivity as Abscisic Acid Receptor Antagonists
Authors: Mikame Yu , Yoshida Kazuko , Hashizume Daisuke , Hirai Go , Nagasawa Kazuo , Osada Hiroyuki , Sodeoka Mikiko
Published: December 2018

The PYR/PYL/RCAR protein families have recently emerged as receptors of the phytohormone abscisic acid (ABA, 1), which regulates plant responses to environmental stress. These families have multiple members with different physiological actions, and so selective agonists or antagonists are needed both as tools to elucidate functional differences and as lead compounds for agrochemicals. We previously identified RK460 (rac‐3 a) as a PYR1‐selective antagonist, and showed that it possesses five stereocenters on a 6,5‐cis‐bicyclo skeleton. Here, we synthesized all the stereoisomers of RK460 and evaluated their activity towards a panel of receptors. Relative stereochemistry as well as absolute stereochemistry was important for selective action.
Covalent Surface Functionalization of Calcium Phosphate Nanoparticles with Fluorescent Dyes by Copper‐Catalysed and by Strain‐Promoted Azide‐Alkyne Click Chemistry
Authors: Rojas‐Sánchez Leonardo , Sokolova Viktoriya , Riebe Steffen , Voskuhl Jens , Epple Matthias
Published: December 2018

Spherical calcium phosphate nanoparticles with a solid core diameter around 90 nm (from scanning electron microscopy, SEM) were coated with a silica shell and then covalently functionalized by azide groups. To these azide groups, all kinds of alkyne‐carrying molecules can be covalently attached by copper‐catalysed azide‐alkyne cycloaddition (CuAAC) and by strain‐promoted azide‐alkyne cycloaddition (SPAAC) at a very high density. This was demonstrated for a number of dyes (FAM, TAMRA, Cy5, Alexa Fluor™ 488, and an aromatic thioether with aggregation‐induced emission (AIE) properties). It was also possible to attach more than one molecule to the surface of one particle by two‐step click reaction, permitting the synthesis of multimodal nanoparticles that are stable under biological conditions. The nanoparticles have a hydrodynamic diameter of around 200 nm (from dynamic light scattering, DLS), which makes them suitable for uptake by cells. The strongly fluorescing nanoparticles were easily taken up by cells as demonstrated by fluorescence microscopy, confocal laser scanning microscopy (CLSM), and structured illuminated microscopy (SIM).
Discovering Transcriptional Regulatory Elements From Run‐On and Sequencing Data Using the Web‐Based dREG Gateway
Authors: Chu Tinyi , Wang Zhong , Chou Shao‐Pei , Danko Charles G.
Published: December 2018

Transcription is a chromatin mark that can be used effectively to identify the location of active enhancers and promoters, collectively known as transcriptional regulatory elements (TREs). We recently introduced dREG, a tool for the identification of TREs using run‐on and sequencing (RO‐seq) assays, including global run‐on and sequencing (GRO‐seq), precision run‐on and sequencing (PRO‐seq), and chromatin run‐on and sequencing (ChRO‐seq). In this protocol, we present step‐by‐step instructions for running dREG on an arbitrary run‐on and sequencing dataset. Users provide dREG with bigWig files (in which each read is represented by a single base) representing the location of RNA polymerase in a cell or tissue sample of interest, and dREG returns a list of genomic regions that are predicted to be active TREs. Finally, we demonstrate the use of dREG regions in discovering transcription factors controlling response to a stimulus and predicting their target genes. Together, this protocol provides detailed instructions for running dREG on arbitrary run‐on and sequencing data. © 2018 by John Wiley & Sons, Inc.
Lower Proportion of Spontaneous Adverse Event Reports for Generic Drugs by Comparison With Original Branded Drugs at the Postmarket Stage in Japan
Authors: Takami Akina , Hirata Kaori , Ishiguro Chieko , Hanaoka Hideki , Uyama Yoshiaki
Published: December 2018

We investigated impacts of increased generic drug use on spontaneous adverse event reports (SAERs), because SAERs have been a major source of data for drug safety assessment at the postmarket stage. Reporting proportion of SAERs for the generic drugs was consistently and significantly lower than that for the original branded drugs. The reporting proportion targeting for 55 active product ingredients, which had the longest follow‐up period after generic drug marketed, gradually decreased for the original branded drugs and increased for the generic drugs. However, these transitions did not parallel the changes in market share over the same period. These results suggest that the reporting proportion of SAERs for generic drugs may not keep pace with growth in market share. When generic drugs account for the majority of market share, utilization of multiple sources of information and data, in addition to SAERs, may be a key to assuring drug safety at the postmarket stage.
Does corporate social responsibility encourage sustainable innovation adoption?Empirical evidence fromLuxembourg
Authors: Poussing Nicolas
Published: December 2018

This contribution explores how corporate social responsibility (CSR) might influence the adoption of sustainable innovation. Previous research reveals that CSR effects depend on the specific CSR practices considered; this study accordingly investigates different measures of CSR practices with a strategic perspective: strategic versus responsive CSR. The empirical analysis is based on a survey carried out in Luxembourg in 2008, pertaining to CSR practices in firms, combined with the Community Innovation Survey of 2012. The results gathered from a sample of 286 firms, obtained with a Heckman procedure, highlight the importance of differentiating CSR strategies. Specifically, the results show that CSR activities in general do not lead to sustainable innovation adoption, but strategic CSR can have an effect on its adoption.
Compressive spectrum sensing using chaotic matrices for cognitive radio networks
Authors: Kamel Sara H. , Abd‐el‐Malek Mina B. , El‐Khamy Said E.
Published: December 2018

Compressive sensing is an emerging technique in cognitive radio systems, through which sub‐Nyquist sampling rates can be achieved without loss of significant information. In collaborative spectrum sensing networks with multiple secondary users, the problem is to find a reliable and fast sensing method and to secure communication between members of the same network. The method proposed in this paper provides both quick and reliable detection through compressive sensing and security through the use of deterministic chaotic sensing matrices. Deterministic matrices have an advantage over random ones since they are easier to generate and store. Moreover, it is much easier to verify whether a deterministic matrix satisfies the conditions for compressive sensing compared with random matrices, which is what makes them an interesting area of research in compressive sensing. Also, it would be a great advantage if the sensing matrices also provide inherent security, which is the motivation for using chaotic matrices in this paper, since any slight changes in the chaotic parameters result in highly uncorrelated chaotic sequences, hence entirely different sensing matrices. This makes it impossible to reconstruct the signal without proper knowledge of the parameters used to generate the sensing matrix. They can also be easily regenerated by knowing the correct initial values and parameters. Additionally, new modifications are proposed to the existing structures of chaotic matrices. The performance of chaotic sensing matrices for both existing and modified structures is compared with that of random sensing matrices.
Metastatic granular cell tumor to the breast diagnosed by fine needle aspiration cytology: A case report with review of the literature
Authors: Mir Fatima , Alnajar Hussein , Rohra Prih , Naumaan Anam , Cheng Lin , Gattuso Paolo
Published: December 2018

Granular cell tumors (GCT) are mesenchymal neoplasms of Schwann cell/neural origin. Malignant granular cell tumors (MGCTs) represent <1‐2% of all GCT and defined as tumors demonstrating metastases or destructive local growth. Other clinical parameters suggestive of malignancy include rapid growth, size > 4 cm and necrosis. An apparently inconsistent set of histological features have been described in MGCT. Although the histologic parameters of a GCT are not always predictive of biologic behavior, the presence of atypical features may be indicative of an aggressive clinical behavior (recurrence and metastases). A preoperative estimate of features suggestive of malignancy is important for treatment and prognostication. Diagnosis and prognostication from preoperative fine needle aspiration (FNA) cytology is hampered by the fact that only a few case reports on cytologic features of malignant GCT have been published. We report a case of metastatic MGCT to breast and compare cytologic features to that of primary breast GCT and apocrine/histiocytoid variants of breast carcinoma.
Electrochemical Oxidation of the Phospha‐ and Arsaethynolate Anions, PCO– and AsCO–
Authors: Tambornino Frank , Tanner Eden E. L. , Amin Hatem M. A. , Holter Jennifer , Claridge Tim , Compton Richard G. , Goicoechea Jose M.
Published: December 2018

The anions PCO– and AsCO– are shown to be electroactive and are studied in aqueous and non‐aqueous solutions. Cyclic voltammetry is used to extract fundamental physicochemical parameters such as oxidation peak potentials, and transfer and diffusion coefficients of the anions to better understand the nature of the oxidation process. Variation of the potential scan rate reveals that electro‐oxidation of PCO– with the release of CO is controlled by diffusion and is a one‐electron irreversible process yielding phosphorus‐containing deposits. In contrast, the oxidation of AsCO– is a near electrochemically reversible process, forming pure arsenic deposits, with a chemically irreversible follow‐up reaction. For both anions, the electrode surface is substantially “blocked” by the reaction products. The formed deposits were characterized by scanning electron microscopy and energy dispersive X‐ray spectroscopy.
An empirical investigation of botnet as a service for cyberattacks
Authors: Hammi Badis , Zeadally Sherali , Khatoun Rida
Published: December 2018

During the last years, cloud computing has emerged and imposed itself as a cost‐effective solution for providing high quality Information Technology services. However, beyond a legitimate usage, the benefits of cloud computing are being exploited by attackers in nefarious ways and botnets are among the greatest beneficiaries of this malicious use. This botnet trend is a major issue because it strongly increases the power of massive distributed attacks when leveraging the capabilities of cloud service providers that do not have appropriate detection approaches in place to detect botnets exploiting cloud resources (also referred to as botclouds). We developed a free experimental intra–Cloud Service Provider (CSP) botnet that exploits CSPs' trial versions. We used this intra‐CSP botnet to execute numerous TCP SYN flood and UDP flood attacks during one week. Our empirical results demonstrate that, contrary to what CSPs claim, all the CSPs (with the exception of one) we have tested still cannot detect or issued no warnings when malicious activities were launched from their cloud computing platforms. Besides, CSP's trial versions can easily be exploited to perpetrate large scale cyberattacks. We argue that efficient, cost‐effective, scalable detection approaches that can detect botclouds need to be developed in the future to address this challenge.
Improving momentum strategies using residual returns and option‐implied information
Authors: Liu Ming‐Yu
Published: December 2018

This paper provides an alternative method for enhancing momentum profits by combining residual returns and option‐implied information. The results show that the main benefit of applying residual returns to construct momentum portfolios is generating stable returns. Additionally, the incorporation of implied volatility (IV) spread or IV skew into a residual momentum portfolio is found to significantly raise profits, particularly during bad times and high‐sentiment periods. This is because IV spread and IV skew can dissociate winners/losers with a price underreaction from those with a price overreaction, which suggests that informed traders who perceive price underreactions/overreactions trade in option markets.
Associative memory for conceptually unitized word pairs in mild cognitive impairment is related to the volume of the perirhinal cortex
Authors: Delhaye Emma , Mechanic‐Hamilton Dawn , Saad Laura , Das Sandhitsu R. , Wisse Laura E. M. , Yushkevich Paul A. , Wolk David A. , Bastin Christine
Published: December 2018

Unitization, that is, the encoding of an association as one integrated entity, has been shown to improve associative memory in populations presenting with associative memory deficit due to hippocampal dysfunction, such as amnesic patients with focal hippocampal lesions and healthy older adults. One reason for this benefit is that encoding of unitized associations would rely on the perirhinal cortex (PrC) and thus minimize the need for hippocampal recruitment. Mild cognitive impairment (MCI) is accompanied by a deficit in associative memory. However, unitization has never been studied to explore the potential benefit in associative memory in MCI, maybe because MCI is characterized by PrC pathology. However, the PrC may potentially still function sufficiently to allow for the successful adoption of unitization. In this study, we aimed at assessing whether unitization could attenuate MCI patients' associative memory deficit, and whether the ability to remember unitized associations would be modulated by the integrity of the PrC in MCI patients. Unitization was manipulated at a conceptual level, by encouraging participants to encode unrelated word pairs as new compound words. Participants also underwent a structural MRI exam, and measures of PrC were extracted (Brodmann Areas [BA] 35 and 36). Results showed that, contrary to healthy controls, MCI patients did not benefit from unitization. Moreover, their memory performance for unitized associations was related to the measure of PrC integrity (BA35), while it was not the case in controls. This finding thus suggests that unitization does not help to attenuate the associative deficit in MCI patients, and brings support to the literature linking unitization to the PrC function.