bluuebunny/crossref_metadata_2025_split huggingface dataset:
Accurate Zygote‐Specific Discrimination of Single‐Nucleotide Polymorphisms Using Microfluidic Electrochemical DNA Melting Curves
Authors: Yang Allen H. J. , Hsieh Kuangwen , Patterson Adriana S. , Ferguson B. Scott , Eisenstein Michael , Plaxco Kevin W. , Soh H. Tom 
Published: February 2014

AbstractWe report the first electrochemical system for the detection of single‐nucleotide polymorphisms (SNPs) that can accurately discriminate homozygous and heterozygous genotypes using microfluidics technology. To achieve this, our system performs real‐time melting‐curve analysis of surface‐immobilized hybridization probes. As an example, we used our sensor to analyze two SNPs in the apolipoprotein E (ApoE) gene, where homozygous and heterozygous mutations greatly affect the risk of late‐onset Alzheimer’s disease. Using probes specific for each SNP, we simultaneously acquired melting curves for probe–target duplexes at two different loci and thereby accurately distinguish all six possible ApoE allele combinations. Since the design of our device and probes can be readily adapted for targeting other loci, we believe that our method offers a modular platform for the diagnosis of SNP‐based diseases and personalized medicine.
Palladium‐Catalyzed CH Fluorosilylation of 2‐Phenylpyridines: Synthesis of Silafluorene Equivalents
Authors: Xiao Qing , Meng Xiangtai , Kanai Motomu , Kuninobu Yoichiro 
Published: February 2014

AbstractTreatment of 2‐phenylpyridines with amino(1,3,2‐dioxaborolan‐2‐yl)diphenylsilane produced fluorosilylated 2‐phenylpyridines in good to excellent yields under palladium catalysis. This reaction is the first example of CH fluorosilylation. Single‐crystal X‐ray structure analysis revealed a Lewis acid–base interaction between the silicon and nitrogen atoms, and the obtained fluorosilylated products are silafluorene equivalents. The fluorosilylated products showed stronger fluorescence than the corresponding silafluorene derivative.
Ruthenium‐Catalyzed Oxidative Kinetic Resolution of Unactivated and Activated Secondary Alcohols with Air as the Hydrogen Acceptor at Room Temperature
Authors: Mizoguchi Hirotaka , Uchida Tatsuya , Katsuki Tsutomu 
Published: February 2014

AbstractEnantiopure alcohols are versatile building blocks for asymmetric synthesis and the kinetic resolution (KR) of racemic alcohols is a reliable method for preparing them. Although many KR methods have been developed, oxidative kinetic resolution (OKR), in which dioxygen is used as the hydrogen acceptor, is the most atom‐efficient. Dioxygen is ubiquitous in air, which is abundant and safe to handle. Therefore, OKR with air has been intensively investigated and the OKR of benzylic alcohols was recently achieved by using an Ir catalyst without any adjuvant. However, the OKR of unactivated alcohols remains a challenge. An [(aqua)Ru(salen)] catalyzed OKR with air as the hydrogen acceptor was developed, in which the aqua ligand is exchanged with alcohol and the Ru complex undergoes single electron transfer to dioxygen and subsequent alcohol oxidation. This OKR can be applied without any adjuvant to activated and unactivated alcohols with good to high enantioselectivity. The unique influence of substrate inhibition on the enantioselectivity of the OKR is also described.
Highly Enantioselective Rhodium(I)‐Catalyzed Activation of Enantiotopic Cyclobutanone CC Bonds
Authors: Souillart Laetitia , Parker Evelyne , Cramer Nicolai 
Published: February 2014

AbstractThe selective functionalization of carbon–carbon σ bonds is a synthetic strategy that offers uncommon retrosynthetic disconnections. Despite progress in CC activation and its great importance, the development of asymmetric reactions lags behind. Rhodium(I)‐catalyzed selective oxidative additions into enantiotopic CC bonds in cyclobutanones are reported. Even operating at a reaction temperature of 130 °C, the process is characterized by outstanding enantioselectivity with the e.r. generally greater than 99.5:0.5. The intermediate rhodacycle is shown to react with a wide variety of tethered olefins to deliver complex bicyclic ketones in high yields.
Monolayer HNb3O8 for Selective Photocatalytic Oxidation of Benzylic Alcohols with Visible Light Response
Authors: Liang Shijing , Wen Linrui , Lin Sen , Bi Jinhong , Feng Pingyun , Fu Xianzhi , Wu Ling 
Published: February 2014

AbstractMonolayer HNb3O8 2D nanosheets have been used as highly chemoselective and active photocatalysts for the selective oxidation of alcohols. The nanosheets exhibit improved photocatalytic activity over their layered counterparts. Results of in situ FTIR, DRS, ESR, and DFT calculations show the formation of surface complexes between the Lewis acid sites on HNb3O8 2D nanosheets and alcohols. These complexes play a key role in the photocatalytic activity of the material. Furthermore, the unique structural features of the nanosheets contributed to their high photocatalytic activity. An electron transition from the coordinated alcohol species to surface Nb atoms takes place and initiates the aerobic oxidation of alcohols with high product selectivity under visible light irradiation. This reaction process is distinct from that of classic semiconductor photocatalysis.
Probing the Zintl–Klemm Concept: A Combined Experimental and Theoretical Charge Density Study of the Zintl Phase CaSi
Authors: Kurylyshyn Iryna M. , Fässler Thomas F. , Fischer Andreas , Hauf Christoph , Eickerling Georg , Presnitz Manuel , Scherer Wolfgang 
Published: February 2014

AbstractThe nature of the chemical bonds in CaSi, a textbook example of a Zintl phase, was investigated for the first time by means of a combined experimental and theoretical charge density analysis to test the validity of the Zintl–Klemm concept. The presence of covalent SiSi interactions, which were shown by QTAIM analysis, supports this fundamental bonding concept. However, the use of an experimental charge density study and theoretical band structure analyses give clear evidence that the cation–anion interaction cannot be described as purely ionic, but also has partially covalent character. Integrated QTAIM atomic charges of the atoms contradict the original Zintl–Klemm concept and deliver a possible explanation for the unexpected metallic behavior of CaSi.
Formal Aminocyanation of α,β‐Unsaturated Cyclic Enones for the Efficient Synthesis of α‐Amino Ketones
Authors: Sun Chunrui , O'Connor Matthew J. , Lee Daesung , Wink Donald J. , Milligan Robert D. 
Published: February 2014

AbstractInstallation of amino functionality on organic molecules through direct CN bond formation is an important research objective. To achieve this goal, a 1,2‐aminocyanation reaction was developed. The reaction occurs through the formation of pyrazolines by means of a formal dipolar cycloaddition of cyclic α,β‐unsaturated ketones with lithium trimethylsilyldiazomethane followed by novel protonolytic NN bond cleavage under mild conditions. This two‐step process provides a diverse array of structurally complex free and mono‐alkylated α‐amino ketones in excellent yields.
The Topochemical Pseudomorphosis of a Chloride into a Bismuthide
Authors: Kaiser Martin , Rasche Bertold , Ruck Michael 
Published: February 2014

AbstractThe heterogeneous reaction of crystals of the novel intermetallic subhalide Bi12Rh3Cl2 with a solution of n‐butyllithium at 70 °C led to the complete topochemical exchange of chloride ions for bismuth atoms, that is, the transformation into the isostructural metastable intermetallic superconductor Bi14Rh3. The crystals underwent the reductive pseudomorphosis almost unchanged except some fissures perpendicular to the a‐axis. Detailed inspections of the transformed crystals by electron microscopy indicated no volume defects that would indicate internal chemical reactions. Thus, extensive mass transport must have occurred through the seemingly dense crystal structure. An efficient transport mechanism, based on an unusual breathing mode of the three‐dimensional network formed by edge‐sharing [RhBi8] cubes and antiprisms, is proposed. The replacement of ionic interaction in the chloride by metallic bonding in the binary intermetallic compound closes the pseudo gap in the density of states at the Fermi level. As a result, the rod‐packing of conducting, yet electrically isolated strands of [RhBi8] cubes in Bi12Rh3Cl2 turns into the three‐dimensional metal Bi14Rh3.
A Photochromic Agonist for μ‐Opioid Receptors
Authors: Schönberger Matthias , Trauner Dirk 
Published: February 2014

AbstractOpioid receptors (ORs) are widely distributed in the brain, the spinal cord, and the digestive tract and play an important role in nociception. All known ORs are G‐protein‐coupled receptors (GPCRs) of family A. Another well‐known member of this family, rhodopsin, is activated by light through the cis/trans isomerization of a covalently bound chromophore, retinal. We now show how an OR can be combined with a synthetic azobenzene photoswitch to gain light sensitivity. Our work extends the reach of photopharmacology and outlines a general strategy for converting Family A GPCRs, which account for the majority of drug targets, into photoreceptors.
Concurrent Block Copolymer Polymersome Stabilization and Bilayer Permeabilization by Stimuli‐Regulated “Traceless” Crosslinking
Authors: Wang Xiaorui , Liu Guhuan , Hu Jinming , Zhang Guoying , Liu Shiyong 
Published: February 2014

AbstractThe fabrication of block copolymer (BCP) vesicles (polymersomes) exhibiting synchronized covalent crosslinking and bilayer permeabilization remains a considerable challenge as crosslinking typically leads to compromised membrane permeability. Herein it is demonstrated how to solve this dilemma by employing a stimuli‐triggered crosslinking strategy with amphiphilic BCPs containing photolabile carbamate‐caged primary amines. Upon self‐assembling into polymersomes, light‐triggered self‐immolative decaging reactions release primary amine moieties and extensive amidation reactions then occur due to suppressed amine pKa within hydrophobic milieu. This leads to serendipitous vesicle crosslinking and the process is associated with bilayer hydrophobicity‐to‐hydrophilicity transition and membrane permeabilization.
Combinatorially Designed Lipid‐like Nanoparticles for Intracellular Delivery of Cytotoxic Protein for Cancer Therapy
Authors: Wang Ming , Alberti Kyle , Sun Shuo , Arellano Carlos Luis , Xu Qiaobing 
Published: February 2014

AbstractAn efficient and safe method to deliver active proteins into the cytosol of targeted cells is highly desirable to advance protein‐based therapeutics. A novel protein delivery platform has been created by combinatorial design of cationic lipid‐like materials (termed “lipidoids”), coupled with a reversible chemical protein engineering approach. Using ribonuclease A (RNase A) and saporin as two representative cytotoxic proteins, the combinatorial lipidoids efficiently deliver proteins into cancer cells and inhibit cell proliferation. A study of the structure–function relationship reveals that the electrostatic and hydrophobic interactions between the lipidoids and the protein play a vital role in the formation of protein–lipidoid nanocomplexes and intracellular delivery. A representative lipidoid (EC16‐1) protein nanoparticle formulation inhibits cell proliferation in vitro and suppresses tumor growth in a murine breast cancer model.
Compatibilization of polypropylene/polyamide 6 blends using new synthetic nanosized talc fillers: Morphology, thermal, and mechanical properties
Authors: Yousfi Mohamed , Livi Sebastien , Dumas Angela , Crépin‐Leblond Jerome , Greenhill‐Hooper Mike , Duchet‐Rumeau Jannick 
Published: February 2014

ABSTRACTNew synthetic nanotalc and a commercially available natural fine talc (Luzenac© A3) were chosen in order to establish a comparative study in terms of their contributions on the improvement of the morphology as well as the final properties of PP/PA6 blends prepared by melt processing. At first, the TEM and SEM micrographs showed that both talc particles have a preferential affinity for the more hydrophilic polyamide 6 phase compared with the continuous PP matrix. Moreover, in both cases, the addition of talc fillers induces a significant decrease of the size of the PA6 domains but the better compatibilization efficiency was obtained in the presence of synthetic nanotalc particles. In this work, the positive change induced by the talc nanofillers on the crystallization kinetics and final morphology was highlighted. In addition, compared with natural talc, a highly level of dispersion of talc layers has been obtained with the synthetic nanotalc which is more hydrophilic. Thus, this better dispersion greatly improves the thermal stability of PP/PA6 blends and leads to better mechanical properties (+ 40% in Young's modulus). © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40453.
Fabrication of graphene supported carbon‐coating cobalt and carbon nanoshells for adsorption of toxic gases and smoke
Authors: Hong Ningning , Song Lei , Wang Bibo , Yuan Bibe , Shi Yongqian , Hu Yuan 
Published: February 2014

ABSTRACTGraphene‐supported carbon‐coating cobalt and carbon nanoshells (Co/C‐GNS and CNS‐GNS) were fabricated and their applications in absorbing toxic gases and smoke have been investigated. Co3O4‐loaded reduced graphite oxide was first prepared via a coprecipitation process, then carbon coatings on cobalt nanoparticles were fabricated by a catalytic carbonization process. The obtained hybrids were characterized by X‐ray diffraction, transmission electron microscopy, Raman spectroscopy, N2 absorption/desorption, and thermogravimetric analysis. Co/C core/shell structure and hollow carbon nanoshells in the size range of 15–22 nm were anchored onto the graphene surfaces. The resultant Co/C‐GNS and CNS‐GNS performed an important function in CO removal and smoke suppression during the combustion of acrylonitrile‐butadiene‐styrene. The good performance could be attributed to the combination effect of physical barrier of the GNS, porosity structure of the carbon nanoshells, and carbonization of the Co nanoparticles. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40457.
Synthesis and characterization of maleated glycidyl 3‐pentadecenyl phenyl ether as a functionalized plasticizer for styrene–butadiene rubber/carbon black/silica composites
Authors: Gong Zhan‐Lin , Cen Lan , Wang Shu‐Ting , Chen Fu‐Lin 
Published: February 2014

ABSTRACTMaleated glycidyl 3‐pentadecenyl phenyl ether (M‐GPPE) was synthesized from glycidyl 3‐pentadecenyl phenyl ether (GPPE), a renewable derivative from cardanol, with maleic anhydride (MAH) by grafting copolymerization. The resulting M‐GPPE was used as a functionalized plasticizer for a styrene–butadiene rubber (SBR)/carbon black (CB)/silica composite. The effects of M‐GPPE on the development of the filler network, the extent of silica dispersion, the curing characteristics, and the mechanical performance of the composites were studied. Meanwhile, a comparative study was performed between M‐GPPE and aromatic oil, a traditional plasticizer used in SBR filler formulations. Gel permeation chromatography and IR and 1H‐NMR analysis results confirmed the occurrence of the grafting reaction between GPPE and MAH and the potential structure of M‐GPPE. The thermostability of GPPE was improved by grafting copolymerization with MAH, as shown by thermogravimetric analysis results. The presence of M‐GPPE resulted in a shorter curing time and better aging properties in the SBR composite compared with GPPE. The mechanical properties, dynamic mechanical analysis, and transmission electron microscopy analysis showed that the maleate of GPPE could enhance the compatibility between SBR and silica, improve the dispersion of silica in SBR, and partially replace the aromatic oil in the SBR/CB/silica composite formulation. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40462.
Surface molecularly imprinted polymer prepared by reverse atom transfer radical polymerization for selective adsorption indole
Authors: Cao Yang , Liu Lukuan , Xu Wanzhen , Wu Xiangyang , Huang Weihong 
Published: February 2014

ABSTRACTThe preparation of indole molecularly imprinted polymers (indole‐MIPs) using 4‐vinylpyridine as functional monomer, silica gel as matrix were used to adsorb indole from fuel oil specifically. The reverse atom transfer radical polymerization (RATRP) technology was introduced to prepare the surface molecularly imprinted polymers, and the precipitation polymerization was adopted in the preparation process. The obtained indole‐MIPs were characterized by nitrogen adsorption, Fourier transform infrared spectrometry and scanning electron microscopy. The results show that indole‐MIPs were provided with the larger surface areas and more pores. The adsorption capacity of indole‐MIPs was 31.80 mg g−1 at 298 K, and the adsorption equilibrium was reached in a short time. The adsorption process was spontaneous by thermodynamic analysis, and an appropriate decrease in temperature could enhance the adsorption capacity. The adsorption process obeyed pseudo‐second‐order kinetic model by kinetics analysis. The isotherm analysis results show that both Langmuir and Sips equations were suitable to experimental data. The selective adsorption and reusable performance of indole‐MIPs were favorable. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40473.
Improving the thermal and mechanical properties of poly(vinyl butyral) through the incorporation of acid‐treated single‐walled carbon nanotubes
Authors: Zanjanijam Ali Reza , Hajian Morteza , Koohmareh Gholam Ali 
Published: February 2014

ABSTRACTIn this study, to investigate the effect of functionalized carbon nanotubes on the thermal and mechanical properties of the poly(vinyl butyral) (PVB) resin, PVB/functionalized single‐walled carbon nanotube (f‐SWCNT) composites were fabricated by a solution casting method. The functionalized nanotubes were prepared by acid treatment. The formation of oxygen‐containing functional groups on the surface of the nanotubes was confirmed by Fourier transform infrared spectroscopy, energy‐dispersive X‐ray spectroscopy, and scanning electron microscopy (SEM) measurements. SEM analysis also showed that the nanotubes were dispersed well in the PVB matrix. The thermal stability of the composites were investigated with thermogravimetric analysis, and the results show better stability for PVB in the presence of a very low content of the f‐SWCNTs. The prepared composites exhibited a significant increase in the temperature of degradation at 50 wt % loss and also in the onset temperature and decomposition temperature at the maximum rate of weight loss of butyral degradation. A significant enhancement in the mechanical properties was also achieved for these prepared composites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40481.
Flexible‐elastic copolymerized polyurethane‐tannin foams
Authors: Basso Maria Cecilia , Giovando Samuele , Pizzi Antonio , Pasch Harald , Pretorius Nadine , Delmotte Luc , Celzard Alain 
Published: February 2014

ABSTRACTOpen cell foams obtained by the simultaneous coreaction of condensed flavonoid tannins with an alkoxylated fatty amine and polymeric diphenylmethane isocyanate yielded highly flexible/elastic polyurethane foams. Copolymerized amine/isocyanate/tannin oligomers were identified by 13C NMR and MALDI‐TOF spectroscopy. In general, between 30% and 50% of natural tannins is added to the components used to obtain polymerisation of the polyurethane. The characteristic of these new, partially biosourced polyurethanes is that the tannin present slows down burning, some of them can be made flame self‐extinguishing and if burning they neither flow nor asperge flaming material around, contrary to what occurs with normal polyurethanes. This limits the possibility of transmitting fire to other materials in the same environment. Cyclic compression tests were carried out showing that after 50 cycles foam recovery was in excess of 80%. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40499.
Nonsalt 1‐(arylmethyloxy)pyrene photoinitiators capable of initiating cationic polymerization
Authors: Uchida Naoki , Nakano Haruka , Igarashi Tetsutaro , Sakurai Tadamitsu 
Published: February 2014

ABSTRACTAnalysis of photoproducts derived from 1‐(methoxynaphthalen‐1‐ylmethyloxy)pyrene initiators and polymer end groups demonstrated that methoxynaphthalen‐1‐ylmethyl carbocation is involved in the initiation steps for both styrene (St) and cyclohexene oxide (CHO) polymerization. Charge transfer from the pyrenyloxy oxygen atom to the methoxynaphthalen‐1‐ylmethyl chromophore in the singlet excited state is assumed to be responsible for the efficient generation of the carbocation species, which also initiates the copolymerization of St and CHO. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40510.
Synthesis of Ultra‐Stable Fluorescent Carbon Dots from Polyvinylpyrrolidone and Their Application in the Detection of Hydroxyl Radicals
Authors: Ren Xiangling , Liu Jing , Meng Xianwei , Wei Jianfei , Liu Tianlong , Tang Fangqiong 
Published: February 2014

AbstractHighly biocompatible and highly photostable fluorescent carbon dots (C dots) were obtained through a simple and nontoxic one‐pot hydrothermal method. Polyvinylpyrrolidone, a common and low‐cost biocompatibility reagent, was used as the only carbon source for the first time. The resulting water‐soluble C dots showed a quantum yield of up to 23.58 % with low cytotoxicity, favorable photoluminescent properties, and good photostability. Importantly, the fluorescence intensities of the C dots were quite stable in high‐salt conditions and over a broad pH range (3.0–10.5). The as‐prepared C dots have been demonstrated to be an excellent probe for hydroxyl radicals sensing based on the fluorescence quenching with great sensitivity and specificity. This opens up a new application field for C dots.
Synthesis, Structure and Bonding, Optical Properties of Ba4MTrQ6 (M=Cu, Ag; Tr=Ga, In; Q=S, Se)
Authors: Lei Xiao‐Wu , Yang Min , Xia Sheng‐Qing , Liu Xiao‐Cun , Pan Ming‐Yan , Li Xin , Tao Xu‐Tang 
Published: February 2014

AbstractFour new quaternary chalcogenides, Ba4AgGaS6 (1), Ba4AgGaSe6 (2), Ba4CuInS6 (3), and Ba4AgInS6 (4), were synthesized by solid‐state reactions and their structures were characterized through single‐crystal X‐ray diffraction. In spite of their similar chemical compositions, the flexible arrangement between the transition metals and the triel atoms leads to subtle differences in their polyanion structures. All structures feature similar [MTrQ6]8− 1D polyanionic chains (M=Cu, Ag; Tr=Ga, In; Q=S, Se), which are constructed from corner‐sharing MQ4 or TrQ4 tetrahedra. However, the transition metals and triels are mixed in 1, 2, and 3, but they occupy independent crystallographic sites in 4. As a result, compounds 1–3 belong to the known Ba2CoS3 (Pnma No. 62) or Ba2MnS3 (Pnma No. 62) class, whereas 4 crystallizes in its own structural type within the monoclinic P21/c (No. 14) space group. The structural relationship among these new phases was also studied with the aid of DFT calculations and related optical properties are presented as well.
Excellent Electrochemical Properties of Yolk–Shell MoO3 Microspheres Formed by Combustion of Molybdenum Oxide–Carbon Composite Microspheres
Authors: Ko You Na , Park Seung Bin , Kang Yun Chan 
Published: February 2014

AbstractYolk–shell MoO3 microspheres are prepared by a two‐step process in which molybdenum oxide–carbon (MoOx–C) composite microspheres are first obtained by spray pyrolysis, followed by combustion at 400 °C in air. The yolk–shell microspheres exhibit excellent electrochemical properties and structural stability.