bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhanced Photocatalytic Properties by Forming Tetragonal ZnX/PbO (X = S, Se) Hetero‐Bilayers: A Computational Prediction
Authors: Zhou Jia , Zhen Xiaofeng 
Published: June 2018

AbstractThe formation of van der Waals hetero‐layered structure is a promising strategy to improve the performance of 2D materials in energy‐related applications that is superior to the individual components. In the current theoretical work, first‐principles calculations are employed to investigate novel tetragonal (t‐) ZnX/PbO (X = S, Se) hetero‐bilayers (BLs). The state‐of‐the‐art computations based on quasiparticle GW and Bethe–Salpeter equation have been used to calculate the electronic and optical properties of t‐ZnX/PbO BLs. It is found that the t‐ZnX/PbO BLs have a strong optical absorption in the solar spectrum, making them potentially good candidates for solar energy harvesting. In addition, first‐principles calculations also show there is a clear charge transfer from ZnX layer to PbO layer.
Evolution of Interfacial Structure and Stress Induced by Interfacial Lattice Mismatch in Layered Metallic Nanocomposites
Authors: Hao Huali , Lau Denvid 
Published: June 2018

AbstractThe interfacial structure directly affects the intrinsic residual stress caused by the interfacial lattice mismatch in layered metallic composites. This stress plays a dominant role in the mechanical, optical, magnetic, and thermal properties of nanocomposites. Here, the interfacial structure evolution and atomistic origin of intrinsic residual stress are figured out through the in situ characterization of atom arrangement and rearrangement in layered metallic nanocomposites with different interfacial misfit by using an atomistic approach. It is found that with the increment of the interfacial misfit, the interface roughens while the intrinsic residual stress increases and then reduces. The film structure dominates the evolution of interfacial structure and intrinsic residual stress when the interfacial misfit is low, whereas the effect of substrate structure on the interface and the stress is as important as the film structure with the increase of the interfacial misfit. The work demonstrates how the film structures affect the interfacial structure and intrinsic stress in layered metallic nanocomposites. Both the film and substrate structures should be taken into consideration to design layered composites with excellent properties.
Phototunable Biomemory Based on Light‐Mediated Charge Trap
Authors: Lv Ziyu , Wang Yan , Chen Zhonghui , Sun Long , Wang Junjie , Chen Meng , Xu Zhenting , Liao Qiufan , Zhou Li , Chen Xiaoli , Li Jieni , Zhou Kui , Zhou Ye , Zeng Yu‐Jia , Han Su‐Ting , Roy Vellaisamy A. L. 
Published: June 2018

AbstractPhototunable biomaterial‐based resistive memory devices and understanding of their underlying switching mechanisms may pave a way toward new paradigm of smart and green electronics. Here, resistive switching behavior of photonic biomemory based on a novel structure of metal anode/carbon dots (CDs)‐silk protein/indium tin oxide is systematically investigated, with Al, Au, and Ag anodes as case studies. The charge trapping/detrapping and metal filaments formation/rupture are observed by in situ Kelvin probe force microscopy investigations and scanning electron microscopy and energy‐dispersive spectroscopy microanalysis, which demonstrates that the resistive switching behavior of Al, Au anode‐based device are related to the space‐charge‐limited‐conduction, while electrochemical metallization is the main mechanism for resistive transitions of Ag anode‐based devices. Incorporation of CDs with light‐adjustable charge trapping capacity is found to be responsible for phototunable resistive switching properties of CDs‐based resistive random access memory by performing the ultraviolet light illumination studies on as‐fabricated devices. The synergistic effect of photovoltaics and photogating can effectively enhance the internal electrical field to reduce the switching voltage. This demonstration provides a practical route for next‐generation biocompatible electronics.
Insights into identifying habitat hot spots and migratory corridors of green turtles in the South China region
Authors: Ng Connie Ka Yan , Gu He Xiang , Li Tsung Hsien , Ye Ming Bin , Xia Zhong Rong , Zhang Fei Yan , Duan Jin Xia , Hsu Chung Kang , Balazs George H. , Murphy Margaret B. 
Published: June 2018

Abstract

Sea turtles are globally endangered, and face daily anthropogenic threats, such as direct take, by‐catch, and habitat degradation. Current research efforts on sea turtles in the South China region mainly focus on captivity and husbandry, haematology and blood chemistry, and nesting ecology. Published information on the marine habitat use of wild populations is limited.
This situation therefore creates a pressing need for scientific research on free‐ranging sea turtles as a foundation for habitat management and species protection in South China. In this study, habitat use and oceanic movement of nesting, and by‐catch or stranded green turtles, were determined by satellite tracking combined with home‐range analysis.
Coupled with previous findings, the foraging grounds of several sea turtle species (green turtle Chelonia mydas, hawksbill turtle Eretmochelys imbricata and loggerhead Caretta caretta) were mainly distributed along the coasts of Hainan Island Province and Guangdong Province, mainland China, as well as Taiwan and the Philippines, and the outlying islands in the South China Sea and East China Sea.
Habitat hot spots and migratory corridors of green turtles, in particular nesting turtles in South China, were identified. Coastal waters near Wanning City of Hainan Island, the eastern Leizhou Peninsula, Iriomote‐jima and Ishigaki‐shima of the Ryukyu Islands of Japan, and Dao Bach Long Vi of Vietnam serve as foraging grounds for nesting green turtles from different origins in South China. Moreover, the Paracel (Xisha) and the Pratas (Dongsha) Islands in the South China Sea, Huidong Gangkou, and its vicinity in mainland China, and Liouciou Island and Penghu Island of Taiwan contain both nesting sites and foraging grounds for green turtles.
The sites that are associated with migratory corridors, in particular Hainan Island, eastern Leizhou Peninsula, and Liouciou Island, which currently lack conservation plans for sea turtles, should be given higher priority for habitat and species protection.
Synthesis and biological evaluation of some new tricyclic pyrrolo[3,2‐e]tetrazolo[1,5‐c]pyrimidine derivatives as potential antitubercular agents
Authors: Patil Yogesh , Shingare Ramesh , Choudhari Amit , Borkute Rachana , Sarkar Dhiman , Madje Balaji R. 
Published: June 2018

AbstractA series of new tricyclic pyrrolo[3,2‐e]tetrazolo[1,5‐c]pyrimidines 8a–l were synthesized and characterized by IR, NMR (1H and 13C), and mass spectral analysis. The newly synthesized compounds 8a–l were inspected for their in vitro antitubercular activity against Mycobacterium tuberculosis (MTB) H37Ra using an established XTT reduction menadione assay (XRMA). The title compounds exhibited minimum inhibitory concentrations (MIC90) ranging from 0.09 to >30 μg/mL. Five compounds (8c, 8i–l) were further confirmed for their dose‐dependent effect against MTB. These compounds were evaluated in the THP‐1 infection model, where 8i (MIC90 = 0.35 μg/mL), 8j (MIC90 = 1.17 μg/mL), 8k (MIC90 = 2.38 μg/mL), and 8l (MIC90 = 1.17 μg/mL) demonstrated significant antitubercular activity. All the ex vivo active compounds showed insignificant cytotoxicity against the human cancer cell lines, HeLa, MCF‐7, and THP‐1. Inactivity of all these compounds against Gram positive and Gram negative bacteria indicates their specificity. Molecular docking studies in the active site of the sterol 14alpha‐demethylase (CYP51) enzyme revealed a similar binding mode to the native ligand in the crystal structure, thereby helping to understand the ligand–protein interactions and to establish a structural basis for inhibition of MTB. The results suggest novel pharmacophores as selective and specific inhibitors against MTB that can be explored further to synthesize lead compounds against tuberculosis. In summary, the results clearly indicate the identification of some novel, selective, and specific inhibitors against MTB that can be explored further for potential antitubercular drugs.
A One‐Pot “Triple‐C” Multicyclization Methodology for the Synthesis of Highly Constrained Isomerically Pure Tetracyclic Peptides
Authors: Richelle Gaston J. J. , Schmidt Marcel , Ippel Hans , Hackeng Tilman M. , van Maarseveen Jan H. , Nuijens Timo , Timmerman Peter 
Published: June 2018

AbstractA broadly applicable one‐pot methodology for the facile transformation of linear peptides into tetracyclic peptides through a chemoenzymatic peptide synthesis/chemical ligation of peptides onto scaffolds/copper(I)‐catalyzed reaction (CEPS/CLIPS/CuAAC; “triple‐C”) locking methodology is reported. Linear peptides with varying lengths (≥14 amino acids), comprising two cysteines and two azidohomoalanines (Aha), were efficiently cyclized head‐to‐tail by using the peptiligase variant omniligase‐1 (CEPS). Subsequent ligation–cyclization with tetravalent (T41/2) scaffolds containing two bromomethyl groups (CLIPS) and two alkyne functionalities (CuAAC) yielded isomerically pure tetracyclic peptides. Sixteen different functional tetracycles, derived from bicyclic inhibitors against urokinase plasminogen activator (uPA) and coagulation factor XIIa (FXIIa), were successfully synthesized and their bioactivities evaluated. Two of these (FF‐T41/2) exhibited increased inhibitory activity against FXIIa, compared with a bicyclic control peptide. The corresponding hetero‐bifunctional variants (UF/FU‐T41/2), with a single copy of each inhibitory sequence, exhibited micromolar activities against both uPA and FXIIa; thus illustrating the potential of the “bifunctional tetracyclic peptide” inhibitor concept.
Successful treatment of dens invaginatus type 3 with infected invagination, vital pulp, and cystic lession: A case report
Authors: Dembinskaite Ausra , Veberiene Rita , Machiulskiene Vita 
Published: June 2018

Key Clinical MessageAll efforts should be aimed to safe permanent tooth for adolescents. Presented rare case confirms a possibility to save a tooth with Oehlers Type 3 anomaly with peri‐invaginated periodontitis and to preserve vitality of the tooth pulp, even when surgical cyst removal is performed.
Penile lesion in a dialysis patient: Time to get an X‐ray
Authors: Koratala Abhilash , Chamarthi Gajapathiraju 
Published: June 2018

Key Clinical MessageCalciphylaxis or calcific uremic arteriolopathy is a rare and serious disorder typically seen in patients with end‐stage renal disease that manifests as skin ischemia and necrosis and histologically characterized by calcification of dermal arterioles. Penis is a rare site of involvement and biopsy is not typically recommended, making the diagnosis clinico‐radiologic.
Oxoberyllates SrBeO2 and Sr12Be17O29 as Novel Host Materials for Eu2+ Luminescence
Authors: Strobel Philipp , Niklaus Robin , Schmidt Peter J. , Schnick Wolfgang 
Published: June 2018

AbstractBeryllate structures are marginally investigated, but show intriguing structural relations to oxo‐ and nitridosilicates. A typical feature is the coordination of Be in both trigonal planar and tetrahedral coordination by O. A broad range of structures is accessible by variable combinations of both building units. Three novel ternary Sr‐oxoberyllates are characterized by single‐crystal X‐ray diffraction analysis, density functional theory calculations and investigations on luminescence properties: α‐SrBeO2, β‐SrBeO2 and Sr12Be17O29 are obtained with oxoberyllate substructures, made up of either BeO3 triangles or BeO4 tetrahedra. The compounds can be described as chain‐ and layer‐type beryllates. When excited with blue light of (In,Ga)N LED chips, β‐SrBeO2 and Sr12Be17O29 show visible emission in the yellow and orange spectral range, respectively, upon doping with Eu2+. Exceptional narrow‐band yellow emission (λem=564 nm, fwhm=55 nm) makes β‐SrBeO2:Eu2+ a promising phosphor for application in phosphor‐converted (pc‐)LEDs.
Phosphoryl‐Transfer Reaction in RNA under Alkaline Conditions
Authors: Acosta‐Silva Carles , Bertran Joan , Branchadell Vicenç , Oliva Antoni 
Published: June 2018

AbstractThe phosphoryl‐transfer reaction in RNA under alkaline conditions by exploring the influence of several solvents theoretically was studied. The calculations were carried out by using the M06‐2X functional and the solvents were taken as a continuum by using the solvent model density (SMD) method. The main findings show that the O2′‐P‐O5′ angle in the reactants, the free activation energies, and the reaction mechanism are clearly dependent on the dielectric constant of the environment, thus showing that the electrostatic term is the determining factor for this chemical system with two negative charges. Our study seems to indicate that water, the solvent with the greatest dielectric constant, would be the solvent that increases the reaction rate the most. As this outcome was not the case in enzymatic catalysis, one has to conclude that, in the case of proteins as well as for ribozymes, the enzymatic catalysis is not mainly due to the solvent reaction field, but to local electrical fields as a result of enzyme preorganization.
Lewis Superacids: Classifications, Candidates, and Applications
Authors: Greb Lutz 
Published: June 2018

AbstractLewis acids play a major role in all areas of chemistry. For a long time, toxic, corrosive and oxidizing SbF5 was considered as the strongest Lewis acid known. Lately, species significantly exceeding the Lewis acidity of SbF5 have been realized and were termed Lewis superacids (LSA). Prospective new candidates emerge steadily, which not only outperform SbF5 by their strength, but also in terms of their accessibility and ease of handling. In principle, Lewis superacids allow us to combine the outstanding activity of Brønsted superacids with the excellent selectivity of a common Lewis acid. However, the broad application of Lewis superacids in synthesis is all but popular. The present review deals with strong Lewis acids. First, it critically discusses Lewis acidity scaling methods and suggests an extended definition for Lewis superacidity. It then summarizes the properties and applications of the strongest currently known Lewis acids, indexed by the fluoride ion affinity (FIA). The supporting information contains a comprehensive list of experimentally and theoretically derived FIA data as a guide for the choice of Lewis acidic reagents/catalyst. This contribution shall encourage the search for new Lewis superacids and promote their application in non‐specialized laboratories.
Triply Linked Porphyrinoids
Authors: Tanaka Takayuki , Osuka Atsuhiro 
Published: June 2018

AbstractTriply linked porphyrin arrays, so called porphyrin tapes, are intriguing molecules in terms of their planar structures, far red‐shifted absorption bands, multi‐charge storage abilities, and high conductivities. Recently, porphyrin tape variants such as porphyrin‐expanded porphyrin hybrid tapes, porphyrin arch‐tapes, corrole tapes, and a subporphyrin tape have been explored as novel π‐conjugated materials. These new molecules exhibit electronic and structural characteristics owing to direct triple linkages. This Minireview first discusses the fundamental properties of the parent porphyrin tapes and the peripherally functionalized porphyrin tapes. Then, a focus has been placed on the syntheses, structures, and unique properties of the recently explored porphyrin tape variants.
Towards High Performance Metal–Organic Framework–Microporous Polymer Mixed Matrix Membranes: Addressing Compatibility and Limiting Aging by Polymer Doping
Authors: Sabetghadam Anahid , Liu Xinlei , Orsi Angelica F. , Lozinska Magdalena M. , Johnson Timothy , Jansen Kaspar M. B. , Wright Paul A. , Carta Mariolino , McKeown Neil B. , Kapteijn Freek , Gascon Jorge 
Published: June 2018

AbstractMembrane separation for gas purification is an energy‐efficient and environment‐friendly technology. However, the development of high performance membranes is still a great challenge. In principle, mixed matrix membranes (MMMs) have the potential to overcome current materials limitations, but in practice there is no straightforward method to match the properties of fillers and polymers (the main components of MMMs) in such a way that the final membrane performance reflects the high performance of the microporous filler and the processability of the continuous polymer phase. This issue is especially important when high flux polymers are utilized. In this work, we demonstrate that the use of small amounts of a glassy polymer in combination with high performance PIM‐1 allow for the preparation of metal–organic framework (MOF)‐based MMMs with superior separation properties and low aging rates under humid conditions, meeting the commercial target for post‐combustion CO2 capture.
Triflimide: An Overlooked High‐Performance Catalyst of the Mukaiyama Aldol Reaction of Silyl Ketene Acetals with Ketones
Authors: Bae Han Yong , List Benjamin 
Published: June 2018

AbstractThe Mukaiyama aldol reaction is a widely applied carbon–carbon bond forming reaction. However, despite numerous well‐established methods using aldehydes as acceptors, only few examples exist with ketones. Here we report a highly practical catalytic approach to this transformation, namely, the triflimide catalyzed Mukaiyama aldol reaction of silyl ketene acetals with ketones. This method exhibits a broad substrate scope, is very rapid, tolerates functionalized substrates, and requires only parts‐per‐million catalyst loadings with preparative scale reactions up to hundreds of grams in excellent purity (>99 %).
Synthesis and Antiviral Evaluation of TriPPPro‐AbacavirTP, TriPPPro‐CarbovirTP, and Their 1′,2′‐cis‐Disubstituted Analogues
Authors: Weising Simon , Sterrenberg Vincente , Schols Dominique , Meier Chris 
Published: June 2018

AbstractHerein we describe the synthesis of lipophilic triphosphate prodrugs of abacavir, carbovir, and their 1′,2′‐cis‐substituted carbocyclic analogues. The 1′,2′‐cis‐carbocyclic nucleosides were prepared by starting from enantiomerically pure (1R,2S)‐2‐((benzyloxy)methyl)cyclopent‐3‐en‐1‐ol by a microwave‐assisted Mitsunobu‐type reaction with 2‐amino‐6‐chloropurine. All four nucleoside analogues were prepared from their 2‐amino‐6‐chloropurine precursors. The nucleosides were converted into their corresponding nucleoside triphosphate prodrugs (TriPPPro approach) by application of the H‐phosphonate route. The TriPPPro compounds were hydrolyzed in different media, in which the formation of nucleoside triphosphates was proven. While the TriPPPro compounds of abacavir and carbovir showed increased antiviral activity over their parent nucleoside, the TriPPPro compounds of the 1′,2′‐cis‐substituted analogues as well as their parent nucleosides proved to be inactive against HIV.
Generation of Vanadium Oxide Quantum Dots with Distinct Fluorescence and Antibacterial Activity via a Room‐Temperature Agitation Strategy
Authors: Huang Lei , Niu Yusheng , Xu Gengfang , Wang Yao , Yuan Lili , Xu Yuanhong , Li Ronggui 
Published: June 2018

AbstractVanadium oxide (VOx) nanomaterials have been attracting great attention recently due to their outstanding physicochemical properties. Engineering VOx into quantum dots (QDs) should bring new properties and potential for applications, but has not been reported until now. Meanwhile, the shortcomings in QDs synthesis such as needing high temperature and expensive instruments still need to be overcome. Herein, VOxQDs were generated via a simple ultrasonic and agitation strategy at room temperature using DMSO as both solvent and exfoliation agent. The VOx QDs exhibited blue fluorescence under 365 nm ultraviolet irradiation. They were with good monodispersion, narrow size distribution and average particle size of 3.3±0.3 nm. The VOxQDs can be used as a competitive fluorescent sensing probe for label‐free specific detection of Fe3+ and PPi based on the ON‐OFF or ON‐OFF‐ON fluorescent principle, respectively. Moreover, the antibacterial activity of the as‐prepared VOxQDs was found, which could damage the cell membrane and inhibit the bacterial growth of both Gram (+) (Staphylococcus aureus) and Gram (−) (Escherichia coli) bacteria, respectively.
Mitochondrial Subtype Identification and Characterization
Authors: Daniele Joseph R. , Heydari Kartoosh , Dillin Andrew 
Published: June 2018

AbstractHealthy, functional mitochondria are central to many cellular and physiological phenomena, including aging, metabolism, and stress resistance. A key feature of healthy mitochondria is a high membrane potential (Δψ) or charge differential (i.e., proton gradient) between the matrix and inner mitochondrial membrane. Mitochondrial Δψ has been extensively characterized via flow cytometry of intact cells, which measures the average membrane potential within a cell. However, the characteristics of individual mitochondria differ dramatically even within a single cell, and thus interrogation of mitochondrial features at the organelle level is necessary to better understand and accurately measure heterogeneity. Here we describe a new flow cytometric methodology that enables the quantification and classification of mitochondrial subtypes (via their Δψ, size, and substructure) using the small animal model C. elegans. Future application of this methodology should allow research to discern the bioenergetic and mitochondrial component in a number of human disease and aging models, including, C. elegans, cultured cells, small animal models, and human biopsy samples. © 2018 by John Wiley & Sons, Inc.
Synthesis of Bare Iron Nanoparticles from Ferrocene Hexane Solution by Femtosecond Laser Pulses
Authors: Okamoto Takuya , Nakamura Takahiro , Kihara Ryo , Asahi Tsuyoshi , Sakota Kenji , Yatsuhashi Tomoyuki 
Published: June 2018

AbstractIron‐based nanoparticles (FeNPs) have unique and attractive properties such as superparamagnetism, biocompatibility, and catalytic activity. Although the synthesis of precious metal NPs from a metal in liquid and/or metal salt solution by a pulsed laser has been investigated, comparably little effort has been devoted to examine the production of FeNPs. Here we report the synthesis of carbon‐shell free spherical NPs of iron oxide (magnetite) from ferrocene hexane solution by femtosecond near infrared laser pulses. Nanosecond UV laser pulses are used to compare the evolution of the particle size distribution as a function of laser irradiation time. The size of NPs remains constant even for extended exposure to femtosecond laser pulses, whereas it grows with exposure to nanosecond laser pulses. The primary particles are generated by photochemical reactions regardless of pulse duration; however, the fragmentation of NPs by successive femtosecond laser pulses regulates the particle size.
Monolayer AsTe2: Stable Robust Metal in 2D, 1D and 0D
Authors: Badalov S. V. , Kandemir A. , Sahin H. 
Published: June 2018

AbstractThe structural, phononic, and electronic properties of the monolayer structures of AsTe2 are characterized by performing density functional theory (DFT) calculations. Total energy optimization and phonon calculations reveal that single layers of the 2H‐AsTe2 and 1T‐AsTe2 phases form dynamically stable crystal structures. Electronic structure analysis also shows that both 2H and 1T phases have nonmagnetic metallic character. It is also predicted that the metallic nature of the ultra‐thin both 2H‐AsTe2 and 1T‐AsTe2 structures remain unchanged even under high biaxial strain values. For further examination of the dimensionality effect in the robust metallicity in 2D AsTe2 phases, electronic characteristics of 1D nanoribbons and 0D quantum dots are also investigated. It is found that independent from the dimension and crystallographic orientations 0D and 1D structures of 2H‐ and 1T‐AsTe2 structures have metallic behavior. It is found that single layers of AsTe2 are quite promising materials for nanodevice applications owing to the robust metallic character.