bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reprogrammable Chemical 3D Shaping for Origami, Kirigami, and Reconfigurable Molding
Authors: Oyefusi Adebola , Chen Jian 
Published: May 2017

AbstractOrigami‐ and kirigami‐based design principles have recently received strong interest from the scientific and engineering communities because they offer fresh approaches to engineering of structural hierarchy and adaptive functions in materials, which could lead to many promising applications. Herein, we present a reprogrammable 3D chemical shaping strategy for creating a wide variety of stable complex origami and kirigami structures autonomously. This strategy relies on a reverse patterning method that encodes prescribed 3D geometric information as a spatial pattern of the unlocked phase (dispersed phase) in the locked phase (matrix phase) in a pre‐stretched Nafion sheet. Building upon the unique chemical reprogramming capability of the Nafion shape memory polymer, we have developed a reconfigurable molding technology that can significantly reduce time, costs, and waste by shaping various 3D materials with high fidelity.
A T‐Shaped Nickel(I) Metalloradical Species
Authors: Yoo Changho , Lee Yunho 
Published: May 2017

AbstractA T‐shaped NiI complex was synthesized using a rigid acridane‐based pincer ligand to prepare a metalloradical center. Structural data displays a nickel ion is embedded in the plane of a PNP ligand. Having a sterically exposed half‐filled
orbital, this three‐coordinate NiI species reveals unique open‐shell reactivity including the homolytic cleavage of various σ‐bonds, such as H−H, N−N, and C−C.
Binary Encoding of Random Peptide Sequences for Selective and Differential Antimicrobial Mechanisms
Authors: Hayouka Zvi , Bella Angelo , Stern Tal , Ray Santanu , Jiang Haibo , Grovenor Chris R. M. , Ryadnov Maxim G. 
Published: May 2017

AbstractBinary encoding of peptide sequences into differential antimicrobial mechanisms is reported. Such sequences are random in composition, but controllable in chain length, are assembled from the same two amino acids, but differ in the stereochemistry of one. Regardless of chirality, the sequences lyse bacteria including the “superbugs” methicillin‐resistant Staphylococcus aureus (MRSA) and vancomycin‐resistant Enterococci (VRE). Sequences with the same chirality, so‐called homochiral sequences, assemble into antimicrobial pores and form contiguous helices that are biologically promiscuous and hemolytic. By contrast, heterochiral sequences that lack such persistence selectively attack bacterial membranes without oligomerizing into visible pores. These results offer a mechanistic rationale for designing membrane‐selective and sequence‐independent antimicrobials.
Cold Snapshot of a Molecular Rotary Motor Captured by High‐Resolution Rotational Spectroscopy
Authors: Domingos Sérgio R. , Cnossen Arjen , Buma Wybren J. , Browne Wesley R. , Feringa Ben L. , Schnell Melanie 
Published: May 2017

AbstractWe present the first high‐resolution rotational spectrum of an artificial molecular rotary motor. By combining chirped‐pulse Fourier transform microwave spectroscopy and supersonic expansions, we captured the vibronic ground‐state conformation of a second‐generation motor based on chiral, overcrowded alkenes. The rotational constants were accurately determined by fitting more than 200 rotational transitions in the 2–4 GHz frequency range. Evidence for dissociation products allowed for the unambiguous identification and characterization of the isolated motor components. Experiment and complementary quantum‐chemical calculations provide accurate geometrical parameters for the C27H20 molecular motor, the largest molecule investigated by high‐resolution microwave spectroscopy to date.
Preparation and investigation of flame‐retardant epoxy resin modified with a novel halogen‐free flame retardant containing phosphaphenanthrene, triazine‐trione, and organoboron units
Authors: Yang Shuang , Zhang Qiaoxin , Hu Yefa 
Published: May 2017

ABSTRACTIn this article, a novel flame retardant (coded as BNP) was successfully synthesized through the addition reaction between triglycidyl isocyanurate, 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide and phenylboronic acid. BNP was blended with diglycidyl ether of bisphenol‐A to prepare flame‐retardant epoxy resin (EP). Thermal properties, flame retardancy, and combustion behavior of the cured EP were studied by thermogravimetric analysis, limited oxygen index (LOI) measurement, UL94 vertical burning test, and cone calorimeter test. The results indicated that the flame retardancy and smoke suppressing properties of EP/BNP thermosets were significantly enhanced. The LOI value of EP/BNP‐3 thermoset was increased to 32.5% and the sample achieved UL94 V‐0 rating. Compared with the neat EP sample, the peak of heat release rate, average of heat release rate, total heat release, and total smoke production of EP/BNP thermosets were decreased by 58.2%–66.9%, 27.1%–37.9%, 25.8%–41.8%, and 21.3%–41.7%, respectively. The char yields of EP/BNP thermosets were increased by 46.8%–88.4%. The BNP decomposed to produce free radicals with quenching effect and enhanced the charring ability of EP matrix. The multifunctional groups of BNP with flame retardant effects in both gaseous and condensed phases were responsible for the excellent flame retardancy of the EP/BNP thermosets. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45291.
Oxaliplatin‐loaded crosslinked polymeric network of chondroitin sulfate‐co‐poly(methacrylic acid) for colorectal cancer: Its toxicological evaluation
Authors: Barkat Kashif , Ahmad Mahmood , Minhas Muhammad Usman , Khalid Ikrima 
Published: May 2017

ABSTRACTThe purpose of this study was to develop and characterize chemically crosslinked chondroitin sulfate‐co‐poly(methacrylic acid) (CSMA) hydrogels for colon targeting of oxaliplatin (OXP) to treat colorectal cancer. CSMA hydrogels were synthesized by free‐radical polymerization. Chondroitin sulfate was chemically crosslinked with methacrylic acid in an aqueous medium. Ammonium peroxodisulfate and N,N‐methylene bisacrylamide were used as the initiator and crosslinker, respectively. Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, X‐ray diffraction, and scanning electron microscopy studies were performed to characterize the fabricated polymeric system. The pH‐sensitive characteristics of the hydrogels were evaluated by swelling dynamics and equilibrium swelling ratio measurements at pH 1.2 and 7.4. A toxicity study of the developed formulations was also conducted on rabbits to determine the toxicity of the drug‐carrier system to the biological system. The characterization studies confirmed the formation of a new polymeric network. A high OXP loading and higher drug release was observed at pH 7.4. The toxicity study confirmed that the developed formulations were nontoxic to the biological system. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45312.
Objective determination of the onset and withdrawal of the South China Sea summer monsoon
Authors: Luo Ming , Lin Lijie 
Published: May 2017

AbstractDetermining the timing (i.e. onset and withdrawal) of monsoon season precisely and objectively is an important yet difficult task. Conventional methods mainly define the monsoon timing as the date when the selected atmospheric variables (e.g. rainfall and wind) exceed an arbitrary threshold. These methods present little explicit justification and are subjective and sensitive to the fluctuation of the selected series. In this study, we propose an objective method to determine the onset and withdrawal of the South China Sea summer monsoon (SCSSM) using the cumulative low‐level zonal wind. Our proposed approach provides an easy, objective, and applicable method that is recommended for the detection of the timing of monsoon season. On the basis of the proposed definition, the SCSSM onset and withdrawal are determined, and their accompanying processes are also examined in this paper. Both onset and withdrawal of SCSSM exhibit strong variability, and the El Niño–Southern Oscillation plays an important role. Via the modification of the western North Pacific subtropical high, a preceding El Niño (La Niña) event can delay (advance) the monsoon onset and advance (delay) the monsoon withdrawal.
Quantification of morusin using LC–MS in rat plasma: Application to a pharmacokinetic study
Authors: Deng Zhipeng , Sun Xiaohui , Yang Shenbao , Zhang Lei , Sun Peilu , Teng Xuepeng , Zhong Hao 
Published: May 2017

AbstractA sensitive LC–MS method was developed for the quantification of morusin in rat plasma using praeruptorin C as internal standard. After extraction with diethyl ether, post‐treatment samples were chromatographed on a Hypersil C18 column. An isocratic mobile phase consisting of methanol–water (70:30, v/v) was applied at a flow rate of 0.4 mL/min. Detection was performed via electrospray ionization source with positive ion mode using selected ion monitoring mode at m/z 443.1 for morusin and m/z 451.0 for IS. Acceptable linearity (r2 ≥ 0.99) was observed over the concentration range of 1.5–800 ng/mL. This method was successfully applied in the pharmacokinetics study of morusin in rats.
Targeting G Protein‐Coupled Receptors by Capture Compound Mass Spectrometry: A Case Study with Sertindole
Authors: Blex Christian , Michaelis Simon , Schrey Anna K. , Furkert Jens , Eichhorst Jenny , Bartho Kathrin , Gyapon Quast Frederick , Marais Anett , Hakelberg Matthias , Gruber Uschi , Niquet Sylvia , Popp Oliver , Kroll Friedrich , Sefkow Michael , Schülein Ralf , Dreger Mathias , Köster Hubert 
Published: May 2017

AbstractUnbiased chemoproteomic profiling of small‐molecule interactions with endogenous proteins is important for drug discovery. For meaningful results, all protein classes have to be tractable, including G protein‐coupled receptors (GPCRs). These receptors are hardly tractable by affinity pulldown from lysates. We report a capture compound (CC)‐based strategy to target and identify GPCRs directly from living cells. We synthesized CCs with sertindole attached to the CC scaffold in different orientations to target the dopamine D2 receptor (DRD2) heterologously expressed in HEK 293 cells. The structure–activity relationship of sertindole for DRD2 binding was reflected in the activities of the sertindole CCs in radioligand displacement, cell‐based assays, and capture compound mass spectrometry (CCMS). The activity pattern was rationalized by molecular modelling. The most‐active CC showed activities very similar to that of unmodified sertindole. A concentration of DRD2 in living cells well below 100 fmol used as an experimental input was sufficient for unambiguous identification of captured DRD2 by mass spectrometry. Our new CCMS workflow broadens the arsenal of chemoproteomic technologies to close a critical gap for the comprehensive characterization of drug–protein interactions.
Deubiquitinase Usp18 prevents cellular apoptosis from oxidative stress in liver cells
Authors: Lai Keng Po , Cheung Angela Hoi Yan , Tse William Ka Fai 
Published: May 2017

AbstractDeubiquitinases (DUBs) deconjugate ubiquitin (UBQ) from ubiquitylated substrates to regulate their activity and stability. They play different cellular functions such as cell cycle regulation, DNA repair, and early embryogenesis. Additionally, studies have demonstrated that some DUBs are the signaling targets of cellular stress such as oxidative stress. Reactive oxygen species are generated during normal mitochondrial oxidative metabolism and proper cellular mechanism could protect the cell from the oxidative stress. However, there are limited studies that specifically focus on the role of DUBs in oxidative stress, and thus the underlying protective mechanism by DUBs is not yet known. The report here, for the first time, applied the mouse‐specific DUB RT2 Profiler PCR array to identify DUBs that are responsive to oxidative stress. Out of the tested 83 DUBs, 15 of them were found to be differentially expressed. Among them, Usp18 was found to be induced with a dose‐ and time‐dependent manner of oxidative stress. In functional studies, depletion of Usp18 could stimulate the p53 and caspase 3 protein levels. In addition, knockdown of Usp18 could lead to the reduced cell viability and increased in apoptotic cell death under oxidative stress. Collectively, Usp18 protects the cells from oxidative stress‐induced apoptosis which may be through the regulation of p53 and caspase 3.
Noninvasive 4D Flow Characterization in a Stirred Tank via Phase‐Contrast Magnetic Resonance Imaging
Authors: Janiga Gábor , Stucht Daniel , Bordás Róbert , Temmel Erik , Seidel-Morgenstern Andreas , Thévenin Dominique , Speck Oliver 
Published: May 2017

AbstractA noninvasive quantification of the hydrodynamics in a stirred tank in space and time using flow‐sensitive phase‐contrast magnetic resonance imaging (PC‐MRI) at 7 Tesla (7 T) is demonstrated. The PC‐MRI technique is able to characterize the unsteady periodic 3D flow velocities with acceptable spatial and temporal resolution and does not imply that optically transparent fluids are employed. PC‐MRI is already widely used for medical diagnostics in order to determine the blood flow velocities, e.g., for cardiovascular applications. However, its utilization for engineering problems is still new, including process engineering. Therefore, it is important to check the suitability of PC‐MRI to applications of practical interest in this field and complement other flow measurement and simulation techniques.
Metal–Ligand Complex‐Induced Ultrafast Charge‐Carrier Relaxation and Charge‐Transfer Dynamics in CdX (X=S, Se, Te) Quantum Dots Sensitized with Nitrocatechol
Authors: Singhal Pallavi , Maity Partha , Jha Sanjay K. , Ghosh Hirendra N. 
Published: May 2017

AbstractThe present work describes the effect of interfacial complex formation on charge carrier dynamics in CdX (X=S, Se, Te) quantum dots (QDs) sensitized nitro catechol (NCAT). To compare experiments were also carried out with catechol (CAT) where no such complexation was observed. Time‐resolved emission studies suggest faster charge separation in CdS(Se)/NCAT system as compared to CdS(Se)/CAT although change in Gibbs free energy for hole transfer is less in former as compared to later. This suggests that complex formation favours charge separation. Similar studies were also carried out in CdTe/NCAT system where hole transfer process was not viable thermodynamically but due to complex formation charge separation was observed. Femtosecond transient absorption studies have been carried out to monitor charge carrier dynamics in early time scale. Transient studies show faster electron cooling in QDs/NCAT system as compared to pure QDs and has been assigned to the complex formation on QDs surface. Interestingly charge recombination dynamics is much faster in QDs/NCAT system as compared to pure QDs which can be attributed to the stronger coupling between QDs and NCAT. Our results suggest a strong metal–ligand complex formation on QDs surface that controls charge carrier dynamics in QDs/molecular adsorbate system and to the best of our knowledge it has never been reported.
Tunable Ligand Effects on Ruthenium Catalyst Activity for Selectively Preparing Imines or Amides by Dehydrogenative Coupling Reactions of Alcohols and Amines
Authors: Higuchi Takafumi , Tagawa Risa , Iimuro Atsuhiro , Akiyama Shoko , Nagae Haruki , Mashima Kazushi 
Published: May 2017

AbstractSelective dehydrogenative synthesis of imines from a variety of alcohols and amines was developed by using the ruthenium complex [RuCl2(dppea)2] (6 a: dppea=2‐diphenylphosphino‐ethylamine) in the presence of catalytic amounts of Zn(OCOCF3)2 and KOtBu, whereas the selective dehydrogenative formation of amides from the same sources was achieved by using another ruthenium complex, [RuCl2{(S)‐dppmp}2] [6 d: (S)‐dppmp=(S)‐2‐((diphenylphosphenyl)methyl)pyrrolidine], in the presence of catalytic amounts of Zn(OCOCF3)2 and potassium bis(trimethylsilyl)amide (KHMDS). Our previously reported ruthenium complex, [Ru(OCOCF3)2(dppea)2] (8 a), was the catalyst precursor for the imine synthesis, whereas [Ru(OCOCF3)2{(S)‐dppmp}2] (8 d), which was derived from the treatment of 6 d with Zn(OCOCF3)2 and characterized by single‐crystal X‐ray analysis, was the pre‐catalyst for the amide formation. Control experiments revealed that the zinc salt functioned as a reagent for replacing chloride anions with trifluoroacetate anions. Plausible mechanisms for both selective dehydrogenative coupling reactions are proposed based on a time‐course study, Hammett plot, and deuterium‐labeling experiments.
Rhodium‐Catalyzed Silylative and Germylative Cyclization with Dehydrogenation Leading to 9‐Sila‐ and 9‐Germafluorenes: A Combined Experimental and Computational Mechanistic Study
Authors: Murai Masahito , Okada Ryo , Asako Sobi , Takai Kazuhiko 
Published: May 2017

AbstractStoichiometric amounts of oxidants are widely used as promoters (hydrogen acceptors) in dehydrogenative silylation of C−H bonds. However, the present study demonstrates that silylative and germylative cyclization with dehydrogenation can proceed efficiently, even without hydrogen acceptors. The combination of [RhCl(cod)]2 and PPh3 was effective for both transformations, and allowed a reduction in reaction temperature compared with our previous report. Monitoring of the reactions revealed that both transformations had an induction period for the early stage, and that the rate constant of dehydrogenative germylation was greater than that of dehydrogenative silylation. Competitive reactions in the presence of 3,3‐dimethyl‐1‐butene indicated that the ratio of dehydrogenative metalation and hydrometalation was affected by reaction temperature when a hydrosilane or hydrogermane precursor was used. Further mechanistic insights of oxidant‐free dehydrogenative silylation, including the origin of these unique reactivities, were obtained by density functional theory studies.
Coordination‐Supported Imidazolate Networks: Water‐ and Heat‐Stable Mesoporous Polymers for Catalysis
Authors: Zhang Pengfei , Yang Shize , Chisholm Matthew F. , Jiang Xueguang , Huang Caili , Dai Sheng 
Published: May 2017

AbstractThe poor water stability of most porous coordination polymers (PCPs) or metal‐organic frameworks (MOFs) is widely recognized as a barrier hampering their practical applications. Here, a facile and scalable route to prepare metal‐containing polymers with a good stability in boiling water (100 °C, 24 h) and air (up to 390 °C) is presented. The bifunctional 1‐vinylimidazole (VIm) with a coordinating site and a polymerizable organic group is introduced as the building block. This core strategy includes the synthesis of a rigid monomer with four VIm branches through a coordination process at room temperature, followed by a radical polymerization. We refer to this material as coordination‐supported imidazolate networks (CINs). Interestingly, CINs are composed of rich mesopores from 2–15 nm, as characterized by low‐energy (60 kV) STEM‐HAADF images. In particular, the stable CINs illustrate a high turnover frequency (TOF) of 779 h−1 in the catalytic oxidation of phenol with H2O as the green solvent.
Biosynthesis of silver nanoparticles applied for UV‐curing conductive ink by using rice straw extract as reducing agent
Authors: Chen Qifeng , Mi Ting , Chen Guangxue , Liu Guhong 
Published: May 2017

AbstractThere is little doubt that nanomaterials are playing a key role in many technologies, and metallic nanoparticles are traditionally synthesized by wet chemical synthesis techniques where the chemicals used are quite often toxic and flammable. In this paper, we report green synthesis of silver nanoparticles using rice straw (RS) extract. The research includes two parts as follows: Firstly, using AgNO3 as the precursor and RS as reducing agent, PVP as protective agent, and controlling the reaction conditions, nano‐silver particles are generated by the liquid phase reduction method. The prepared Ag nanoparticles are examined by Malvern Zetasizer, scanning electron microscopy (SEM), transmission electron microscopy (TEM) with energy‐dispersive X‐ray spectroscopy (EDS), X‐ray diffraction pattern (XRD), and UV spectroscopy. The results show that the size of nano‐silver particles is controllable, they have good dispersion and appearance, and they are stable at long term storage. Finally, using nano‐silver as UV‐curing conductive filler, UV‐curing nano‐silver conductive ink is generated, and its conductive properties are discussed. Results show that the content of conductive filler has an effect on the resistivity of conductive ink.
A statistical analysis for correlation approach to compensate the measured CIELAB colorimetric data for temperature alterations
Authors: Che Jiangning , Senanayake Muditha 
Published: May 2017

AbstractThe main focus of this work was to elucidate the further question of whether the color change correlated linearly with the surface temperature alteration or not. We selected and grouped the colored samples, which were in the form of textile, ceramic, plastic, paint, and ink. Those samples were first measured by IR Thermometer to record exact surface temperature, followed by an immediate color measurement using a spectrophotometer. The color variations of these samples were recorded from about 20°C to 60°C. The trend of CIELAB color coordinates was plotted against surface temperature. The dependency between each CIE colorimetric coordinate and the object's surface temperature was statistically evaluated using Pearson's r, R value, and R‐square analysis. A very strong correlation was observed for ceramic, paint, and ink samples tested, while the textile and plastic sample also exhibited a strong trend. The results added new information about the potential correlation between colorimetric data and temperature. Implications for the future research are discussed.
Image color adjustment for harmony with a target color
Authors: Kim EunJin , Suk Hyeon‐Jeong 
Published: May 2017

AbstractAlthough a number of methods have been developed for image adjustment in various applications, very little work has been done in the context of visual design. In this regard, this article introduces a novel and practical context of image color adjustment and develops a method to adjust an image for harmony with a target color. The experiment with designers revealed that designers made significant changes in hue dimension, and preferred to promote color similarity between the image and the target color. Based on insights from designers, we proposed a method to achieve a harmonious combination of an image and a color element by increasing the hue similarity between them. The result of a user test revealed that our method is particularly useful for images with nonliving objects but less effective for images involving human skin, foods, and so on. It is expected that the practical context investigated in this study can promote a variety of related studies that satisfy the tangible needs of industries and academia.