bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative Monitoring and Visualization of Hydrogen Sulfide In Vivo Using a Luminescent Probe Based on a Ruthenium(II) Complex
Authors: Du Zhongbo , Song Bo , Zhang Wenzhu , Duan Chengchen , Wang Yong‐Lei , Liu Chaolong , Zhang Run , Yuan Jingli 
Published: February 2018

AbstractDevelopment of novel bioanalytical methods for monitoring of H2S is key toward understanding the physiological and pathological functions of this gasotransmitter in live organisms. A ruthenium(II)‐complex‐based luminescence probe, Ru‐MDB (MDB: 4’‐methyl‐[2,2’‐bipyridine]‐4‐yl)methyl 2‐((2,4‐dinitrophenyl)thio)benzoate), was developed by introducing a new H2S responsive masking moiety to a red‐emitting RuII luminophore. Cleavage of this masking group by a H2S‐triggered reaction leads to a luminescence “off–on” response. The long‐lived emissions of Ru‐MDB and its reaction product with H2S allowed quantitative detection of H2S in autofluorescence‐rich human sera and adult zebrafish organs using the time‐gated luminescence mode. Ru‐MDB exhibits red emission, a large Stokes shift, high specificity and sensitivity for H2S detection, and low cytotoxicity, which enables imaging and flow cytometry analysis of lysosomal H2S generation in live inflamed cells under drug stimulation. Monitoring of H2S in live Daphnia magna, zebrafish embryos, adult zebrafish, and mice, was conducted by in vivo imaging using Ru‐MDB as a probe.
Template Synthesis of Three‐Dimensional Hexakisimidazolium Cages
Authors: Sun Li‐Ying , Sinha Narayan , Yan Tao , Wang Yi‐Shou , Tan Tristan T. Y. , Yu Le , Han Ying‐Feng , Hahn F. Ekkehardt 
Published: February 2018

AbstractA procedure for the synthesis of three‐dimensional hexakisimidazolium cage compounds has been developed. The reaction of the trigonal trisimidazolium salts H3L(PF6)3, decorated with three N‐olefinic pendants, and silver oxide yielded trinuclear trisilver(I) hexacarbene molecular cylinders of the type [Ag3L2]3+ with the olefinic pendants from the two different tricarbene ligands arranged in three pairs. Subsequent UV irradiation gave three cyclobutane links between the two tris‐NHC ligands in three [2+2] cycloaddition reactions, thereby generating a three‐dimensional hexakis‐NHC ligand. Removal of the metal ions resulted in the formation of three‐dimensional hexakisimidazolium cages with a large internal cavity.
Dispersion and exfoliation of nanoclays in itaconic acid funcionalized LDPE by ultrasound treatment
Authors: Martínez‐Colunga Juan Guillermo , Sánchez‐Valdes Saúl , Blanco‐Cardenas Armida , Ramírez‐Vargas Eduardo , Ramos‐de Valle Luis Francisco , Benavides‐Cantu Roberto , Espinoza‐Martinez Adriana Berenice , Sanchez‐Lopez Santiago , Lozano‐Ramirez Tomas , Lafleur Pierre G. , Karami Shahir 
Published: February 2018

ABSTRACTPolyethylene–montmorillonite nanocomposites were prepared in the melt applying various ultrasonic powers (231, 347, and 462 W) and temperatures (185, 200, and 215 °C) in the presence of itaconic acid. Dispersion–exfoliation of montmorillonite and in situ low density polyethylene functionalization with itaconic acid were carried out by ultrasound assisted extrusion process. Clay dispersion and exfoliation was evaluated by X‐ray diffraction (XRD) and electronic microscopy (STEM). The degree of grafting itaconic acid into low density polyethylene (LDPE) was determined by infrared analysis (FTIR) and titration technics. Ultrasound‐treated nanocomposites showed improved clay dispersion compared with non‐treated ones. Mechanical properties, XRD, and STEM microscopy indicated that the grafting level, clay dispersion, and exfoliation was directly influenced by IA concentration, temperature, and ultrasonic energy. For instance, the itaconic acid grafted into LDPE was improved from 0.13% to 0.71% when ultrasound power was increased and when temperature was reduced. The modulus was enhanced up to 225 MPa when the ultrasound power was increased up to 462 W. The nanocomposites decomposition temperature, determined by thermogravimetric analysis, was increased nearly 20 °C when 1% w/w itaconic acid was used. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46260.
Biodegradable porous organosilicone‐modified collagen fiber matrix: Synthesis and high oil absorbency
Authors: Du Weining , Dai Guochen , Wang Baochuan , Li Zhengjun , Li Lixin 
Published: February 2018

ABSTRACTWe used hexadecyl trimethyl ammonium bromide as a phase transfer catalyst (PTC) to enhance the effectiveness of a heterogeneous reaction system composed of collagen fiber (CF) and organosilicone modifying agents including epoxy‐polydimethylsiloxane (ES) and/or γ‐glycidoxypropylthrimethoxysilane (GS), in order to improve oil sorption behaviors of the modified products as sorbents. The effects of PTC dosage, organosilicone species or its dosage on the degree of modification of CFs were studied, and the optimum conditions were determined. Subsequently, the surface chemistry and porous structure of the prepared sorbents were thoroughly characterized, and their oil sorption behaviors were also investigated. It was confirmed that both their hydrophobicity‐oleophilicity character and pore structures could be significantly improved by introducing PTC agent and modulating the species or amount of organosilicone, resulting in improved oil sorption behaviors. In addition, the organosilicone modified CF matrix possessed acceptable reusability and biodegradability, and can be implemented as an eco‐friendly sorbent for oil spill cleanup. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46264.
Preparation of a modified diatomite filler via polyethyleneimine impregnation and its application in papermaking
Authors: Shang Wei , Qian Xueren , Yu Dayu 
Published: February 2018

ABSTRACTIn this study, we sequentially modified diatomite (DM) particles with sodium dodecyl sulfate and polyethyleneimine with an impregnation method. Modified DM was used as both a filler and an anionic trash catcher in the papermaking process. The surface morphology, ζ potential, particle size, and Fourier transform infrared spectrum of the modified DM were investigated, and the application performance of the modified DM was evaluated through filler retention, ζ potential, drainability, and cationic demand of the papermaking furnish and the paper strength properties. The results show that the modified DM could be used as a good, novel filler in papermaking. The ζ potential of the surface of the modified DM particles was changed from electronegative to electropositive, and the particle size of the modified DM particles was increased. The retention of the modified DM filler was 16% higher than that of the unmodified DM when the filler dosage was 40%. The higher ζ potential was responsible for the higher retention of the modified DM filler. The drainability of the papermaking furnish was improved efficiently. The anionic trash in the papermaking system was anchored efficiently, and the cationic demand of the papermaking furnish decreased over 85% when the dosage of modified DM was 35%. Compared with the handsheets filled with unmodified DM, the handsheets filled with modified DM had higher strength properties. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46275
Self‐Assembly of Achiral Shape Amphiphiles into Multi‐Walled Nanotubes via Helicity‐Selective Nucleation and Growth
Authors: Ren Li‐Jun , Wu Han , Hu Min‐Biao , Wei Yu‐Han , Lin Yue , Wang Wei 
Published: February 2018

AbstractSoft nanotubes are normally constructed from chiral amphiphiles through helical self‐assembly. Yet, how to self‐assemble achiral molecules into nanotubes is still a challenge. Here, we report the nanotube construction with achiral shape amphiphiles through helical self‐assembly and also unravel the formation mechanisms. The amphiphiles have a dumbbell shape and are composed by covalently linking three achiral moieties together: two unlike clusters and an organic tether. The difference in polarity between the unlike clusters drives the amphiphiles to self‐assemble into single‐ and multi‐walled nanotubes as well as intermediates. Analysis of the key intermediates unravels the self‐assembly mechanism of helicity‐selective nucleation and growth. Meanwhile, direct visualization of the individual clusters in the ribbons displays a two‐dimensional deformed hexagonal lattice. Thus, we speculate that it is the lattice deformation that creates anisotropic tension along different directions of the ribbon which further results in the formation of helical ribbons towards nanotubes by amphiphiles.
Li7Cd4.5Ge4Se16 and Li6.4Cd4.8Sn4Se16: Strong Nonlinear Optical Response in Quaternary Diamond‐Like Selenide Networks
Authors: Guo Yangwu , Li Xiaoshuang , Feng Kai , Li Chao , Zhou Molin , Wu Yicheng , Yao Jiyong 
Published: February 2018

AbstractTwo new selenides with diamond‐like structures, Li7Cd4.5Ge4Se16 and Li6.4Cd4.8Sn4Se16, were synthesized by using a conventional high‐temperature solid‐state reaction method. They crystallize in the space group Pna21 (no. 33) of the orthorhombic system. Their three‐dimensional frameworks consist of corner‐sharing LiSe4, CdSe4, and MSe4 (M=Ge, Sn) tetrahedra. These two compounds exhibit strong powder second‐harmonic generation responses that are about 1.2 and 2.5 times that of the benchmark AgGaS2 at a laser wavelength of λ=2.09 μm, and also demonstrate type I phase‐matchable behavior. The optical bandgaps were determined to be 2.18 and 1.95 eV for Li7Cd4.5Ge4Se16 and Li6.4Cd4.8Sn4Se16, respectively. Furthermore, these two materials exhibit congruent melting behavior at rather low temperatures of 985 and 1060 K, respectively, which makes bulk single crystal growth by using the Bridgman–Stockbarger method possible. Our study indicates that these two materials show advantages over the traditional IR NLO material CdSe and are promising for practical applications.
Synthesis of N‐Doped Mesoporous Carbon Nanorods through Nano‐Confined Reaction: High‐Performance Catalyst Support for Hydrogenation of Phenol Derivatives
Authors: Liu Xueteng , Pang Fei , Ge Jianping 
Published: February 2018

AbstractTraditional hard‐template methods for the preparation of mesoporous carbon structures have been well developed, but there are difficulties associated with complete filling of the organic precursors in ordered mesochannels and exact replication of the templates. Herein, mesoporous carbon nanorods (meso‐CNRs) were synthesized through thermal condensation of furfuryl alcohol followed by the nano‐confined decomposition of polyfurfuryl alcohol in silica nanotubes (SiO2 NTs) with porous shells. Limited and slow release of gaseous water through the porous shells and finite polyfurfuryl precursor inside silica nanotubes are responsible for the formation of the mesoporous structures. Nitrogen can be doped into the meso‐CNRs by adding guanidine hydrochloride to the precursors. The nitrogen dopant not only stabilizes the ultrasmall and active Pd nanocatalyst in the meso‐CNRs but also increases the electron density of Pd and accelerates the dissociation of H2, both of which increase the catalytic activity of the Pd catalyst in hydrogenation reactions.
Multicomponent Synthesis of Isoindolinone Frameworks via RhIII‐Catalysed in situ Directing Group‐Assisted Tandem Oxidative Olefination/Michael Addition
Authors: Wang Liang , Liu Xi , Liu Jian‐biao , Shen Jun , Chen Qun , He Ming‐yang 
Published: February 2018

AbstractA RhIII‐catalysed three‐component synthesis of isoindolinone frameworks via direct assembly of benzoyl chlorides, o‐aminophenols and activated alkenes has been developed. The process involves in situ generation of o‐aminophenol (OAP)‐based bidentate directing group (DG), RhIII‐catalysed tandem ortho C−H olefination and subsequent cyclization via aza‐Michael addition. This protocol exhibits good chemoselectivity and functional group tolerance. Computational studies showed that the presence of hydroxyl group on the N‐aryl ring could enhance the chemoselectivity of the reaction.
Which One is Bulkier: The 3,5‐Dimethylphenyl or the 2,6‐Dimethylphenyl Group? Development of Size‐Complementary Molecular and Macromolecular [2]Rotaxanes
Authors: Sato Hiroki , Aoki Daisuke , Takata Toshikazu 
Published: February 2018

AbstractWe developed novel size‐complementary molecular and macromolecular rotaxanes using a 2,6‐dimethylphenyl terminal group as the axle‐end‐cap group in dibenzo‐24‐crown‐8‐ether (DB24C8)‐based rotaxanes, where the 2,6‐dimethylphenyl group was found to be less bulky than the 3,5‐dimethylphenyl group. A series of molecular and macromolecular [2]rotaxanes that bear a 2,6‐dimethylphenyl group as the axle‐end‐cap were synthesized using unsubstituted and fluorine‐substituted DB24C8. Base‐induced decomposition into their constituent components confirmed the occurrence of deslipping, which supports the size‐complementarity of these rotaxanes. The deslipping rate was independent of the axle length but dependent on the DB24C8 substituents. A kinetic study indicated the rate‐determining step was that in which the wheel is getting over the end‐cap group, and deslipping proceeded via a hopping‐over mechanism. Finally, the present deslipping behavior was applied to a stimulus‐degradable polymer as an example for the versatile utility of this concept in the context of stimulus‐responsive materials.
Biotechnological advances in lactic acid production by lactic acid bacteria: lignocellulose as novel substrate
Authors: Cubas‐Cano Enrique , González‐Fernández Cristina , Ballesteros Mercedes , Tomás‐Pejó Elia 
Published: February 2018

AbstractThe production of high added‐value products from lignocellulose is proposed as a suitable alternative to petroleum‐based resources in terms of environmental preservation, sustainability, and circular economy. Lactic acid is a versatile building block that can be produced via fermentative routes by several groups of microorganisms, including yeasts and microalgae, which are bacteria recognized to achieve the highest concentrations. Lactic acid, among other substances, can be used as a starting point in the production of poly‐lactic acid, which is a biopolymer with many applications due to its resistance, durability, biodegradability, and biocompatibility. Lactic acid production can be performed from lignocellulosic biomass. However, lactic acid production from lignocellulose faces several hurdles such as carbohydrate hydrolysis to release sugars, the co‐utilization of sugar mixtures by the fermenting microorganism, and the presence of degradation compounds released during pretreatment. In this review, a general overview of lactic‐acid bacterial fermentation from lignocellulose is provided, starting from the potential substrates and their composition, the different metabolic pathways involved, and the purification steps. The main challenges are discussed and the newest approaches to solve the limitations of the process are proposed. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd
Single‐Molecule Kinetics of an Enzyme in the Presence of Multiple Substrates
Authors: Singh Divya , Chaudhury Srabanti 
Published: February 2018

AbstractHerein, the catalytic activity of a single enzyme in the presence of multiple substrates is studied. Three different mechanisms of bisubstrate binding, namely, ordered sequential, random sequential and ping‐pong nonsequential pathway, are broadly discussed. By means of the chemical master equation approach, exact expressions for the waiting‐time distributions, the mean turnover time and the randomness parameter as a function of the substrate concentration, such that both concentrations are fixed, but one of them is changed quasi‐statically are obtained. The randomness parameter is not equal to unity at intermediate to high substrate concentrations, which indicates the presence of multiple rate‐limiting steps in the reaction pathway in all three modes of bisubstrate binding. This arises due to transitions between the free enzyme and the enzyme–substrate complexes that occur on comparable timescales. Such turnover statistics of the single enzyme can also distinguish between the different types of bisubstrate binding mechanisms.
Synthesis and Applications of Stenhouse Salts and Derivatives
Authors: Gomes Rafael F. A. , Coelho Jaime A. S. , Afonso Carlos A. M. 
Published: February 2018

AbstractIn recent years, Stenhouse salts have attracted much attention as intermediates for the synthesis of cyclopenten‐2‐enones. This Minireview aims to present an overview of the methods for preparation, further transformation and applications of Stenhouse and Stenhouse‐like salts. In this context, the Piancatelli rearrangement and its variants, and the recently reported donor–acceptor Stenhouse salts (DASA) will be addressed. The photophysical properties of DASA and its applications in colorimetric detection of amines, functionalization of polymers for detection of heat and nerve agents, photolithography and orthogonal photoswitching systems are discussed.
Aggregation‐Induced Emission (AIE) in Ag−Au Bimetallic Nanocluster
Authors: Jin Shan , Liu Wei , Hu Daqiao , Zou Xuejuan , Kang Xi , Du Wenjun , Chen Shuang , Wei Shiqiang , Wang Shuxin , Zhu Manzhou 
Published: February 2018

AbstractHerein we report the synthesis and structure determination of a non‐fluorescent Au4Ag5(dppm)2(SAdm)6(BPh4) (dppm=bis(diphenylphosphino)methane and HSAdm=1‐adamantane mercaptan) nanocluster in methanol with extremely strong AIE when aggregating to the solid state (i.e., film or crystal). This phenomenon was rarely reported in structural determined noble metal nanoclusters. The extended X‐ray absorption fine structure (EXAFS) measurement ruled out the hypothesis that the luminescence originated from the structure change in different states. Besides, the crystal structure (determined by X‐ray diffraction) revealed that the tightly combined left‐ and right‐handed enantiomers induced the strong restriction of intramolecular motions (RIM), which may have an impact on aggregation‐induced emission.
Validation of molecular force field parameters for peptides including isomerized amino acids
Authors: Oda Akifumi , Nakayoshi Tomoki , Fukuyoshi Shuichi , Kurimoto Eiji , Yamaotsu Noriyuki , Hirono Shuichi , Takahashi Ohgi 
Published: February 2018

AbstractRecently, stereoinversions and isomerizations of amino acid residues in the proteins of living beings have been observed. Because isomerized amino acids cause structural changes and denaturation of proteins, isomerizations of amino acid residues are suspected to cause age‐related diseases. In this study, AMBER molecular force field parameters were tested by using computationally generated nonapeptides and tripeptides including stereoinverted and/or isomerized amino acid residues. Energy calculations by using density functional theory were also performed for comparison. Although the force field parameters were developed by parameter fitting for l‐α‐amino acids, the accuracy of the computational results for d‐amino acids and β‐amino acids was comparable to those for l‐α‐amino acids. The conformational energies for tripeptides calculated by using density functional theory were reproduced more accurately than those for nonapeptides calculated by using the molecular mechanical force field. The evaluations were performed for the ff99SB, ff03, ff12SB, and the latest ff14SB force field parameters.
Inpatient utilization and disparities: The last year of life of adolescent and young adult oncology patients in California
Authors: Johnston Emily E. , Alvarez Elysia , Saynina Olga , Sanders Lee M. , Bhatia Smita , Chamberlain Lisa J. 
Published: February 2018

BACKGROUNDStudies of adolescent and young adult (AYA) oncology end‐of‐life care utilization are critical because cancer is the leading cause of nonaccidental AYA death and end‐of‐life care contributes significantly to health care expenditures. This study was designed to determine the quantity of and disparities in inpatient utilization in the last year of life of AYAs with cancer.METHODSThe California Office of Statewide Health Planning and Development administrative discharge database, linked to death certificates, was used to perform a population‐based analysis of cancer patients aged 15 to 39 years who died in 2000‐2011. The number of hospital days and the inpatient costs were determined for each patient in the last year of his or her life, as were clinical and sociodemographic factors associated with high inpatient utilization. Admission patterns as death approached were also evaluated.RESULTSThe 12,883 patients were admitted for 40 days on average in the last year of life, and this cost $151,072 per patient in inpatient costs. As death approached, the admission rates and the percentage of all admissions occurring at nonspecialty centers increased. Five percent of patients used 20% of bed days in the last year (high utilizers). Factors associated with high utilization included younger age (15‐30 years), Hispanic ethnicity, non–health maintenance organization insurance, and hematologic malignancies.CONCLUSIONSAYA oncology decedents were admitted for 40 days in their last year of life. Subgroups with high utilization had distinct sociodemographic and clinical characteristics, and nonspecialty center admissions increased as death approached. This demonstrates the need for palliative care at nonspecialty centers. Future studies need to determine whether these patterns are goal‐concurrent, include high utilizers, and monitor the effects of health care reform. Cancer 2018;124:1819‐27. © 2018 American Cancer Society
Gluten‐free diet during pregnancy alleviates signs of diabetes and celiac disease in NOD mouse offspring
Authors: Haupt‐Jorgensen Martin , Larsen Jesper , Josefsen Knud , Jørgensen Tina Z. , Antvorskov Julie Christine , Hansen Axel K. , Buschard Karsten 
Published: February 2018

AbstractBackgroundGluten‐free (GF) diet during pregnancy ameliorates autoimmune diabetes in nonobese diabetic (NOD) mouse offspring. Due to comorbidity of celiac disease in type 1 diabetes, we hypothesized that GF diet in utero alleviates the humoral and histopathological signs of celiac disease in NOD mice. We aimed to establish the mechanisms behind the diabetes‐protective effect of GF diet in utero.MethodsBreeding pairs of NOD mice were fed a GF or gluten‐containing standard (STD) diet until parturition. The offspring were nursed by mothers on STD diet and continued on this diet until ages 4 and 13 weeks. Analyses of serum antitissue transglutaminase (anti‐tTG) intestine and islet histology, islet transglutaminase (TG) activity, and cytokine expression in T cells from lymphoid organs were performed.ResultsGF versus STD diet in utero led to reduced serum anti‐tTG titre and increased villus‐to‐crypt ratio at both ages. Insulitis along with systemic and local inflammation were decreased, but islet TG activity was unchanged in 13‐week‐old GF mice. These mice had unchanged beta‐cell volumes, but increased islet numbers throughout the prediabetic period.ConclusionsCollectively, GF diet administered during pregnancy improves signs of celiac disease and autoimmune diabetes in the offspring. The diabetes‐ameliorative effect of GF diet in utero is followed by dampening of inflammation, unchanged beta‐cell volume, but increased islet numbers.