bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Supramolecularly Activated Radical Cation for Accelerated Catalytic Oxidation
Authors: Jiao Yang , Li Wan‐Lu , Xu Jiang‐Fei , Wang Guangtong , Li Jun , Wang Zhiqiang , Zhang Xi 
Published: June 2016

AbstractTuning the activity of radicals is crucial for radical reactions and radical‐based materials. Herein, we report a supramolecular strategy to accelerate the Fenton reaction through the construction of supramolecularly activated radical cations. As a proof of the concept, cucurbit[7]uril (CB[7]) was introduced, through host–guest interactions, onto each side of a derivative of 1,4‐diketopyrrolo[3,4‐c]pyrrole (DPP), a model dye for Fenton oxidation. The DPP radical cation, the key intermediate in the oxidation process, was activated by the electrostatically negative carbonyl groups of CB[7]. The activation induced a drastic decrease in the apparent activation energy and greatly increased the reaction rate. This facile supramolecular strategy is a promising method for promoting radical reactions. It may also open up a new route for the catalytic oxidation of organic pollutants for water purification and widen the realm of supramolecular catalysis.
Oil‐Soluble Polymer Brush Grafted Nanoparticles as Effective Lubricant Additives for Friction and Wear Reduction
Authors: Wright Roger A. E. , Wang Kewei , Qu Jun , Zhao Bin 
Published: June 2016

AbstractThe development of high performance lubricants has been driven by increasingly growing industrial demands and environmental concerns. Herein, we demonstrate oil‐soluble polymer brush‐grafted inorganic nanoparticles (hairy NPs) as highly effective lubricant additives for friction and wear reduction. A series of oil‐miscible poly(lauryl methacrylate) brush‐grafted silica and titania NPs were synthesized by surface‐initiated atom transfer radical polymerization. These hairy NPs showed exceptional stability in poly(alphaolefin) (PAO) base oil; no change in transparency was observed after being kept at −20, 22, and 100 °C for ≥55 days. High‐contact stress ball‐on‐flat reciprocating sliding tribological tests at 100 °C showed that addition of 1 wt % of hairy NPs into PAO led to significant reductions in coefficient of friction (up to ≈40 %) and wear volume (up to ≈90 %). The excellent lubricating properties of hairy NPs were further elucidated by the characterization of the tribofilm formed on the flat. These hairy NPs represent a new type of lubricating oil additives with high efficiency in friction and wear reduction.
A methacrylate monomer bearing nitro, aryl, and hydroxyl side groups: Homopolymerization, characterization, dielectric, and thermal degradation behaviors
Authors: Biryan Fatih , Demirelli Kadir 
Published: June 2016

ABSTRACT2‐Hydroxy‐3‐(4‐nitrophenoxy)propyl methacrylate (HNPPMA) monomer was synthesized. The poly(HNPPMA) was prepared by free radical polymerization (FRP) method. The characterization of poly(HNPPMA) was carried out using FT‐IR, NMR, differential scanning calorimetry, and GPC techniques. The thermal stability and degradation behavior of this polymer have been studied by using thermogravimetry (TG), GC‐MS, NMR, and FT‐IR. The results were in comparison to poly[2‐hydroxy‐3‐(1‐naphtyloxy)propyl methacrylate] sample with α‐naphtyloxy side group prepared by the same method in the our previous study. The effect of thermal activation on non‐isothermal decomposition kinetics of poly(HNPPMA) was investigated using thermogravimetric analysis according to Flynn‐Wall‐Ozawa method. The dielectric measurements of poly(HNPPMA) and doped with europium(III)chloride (EuCI3) were investigated by impedance analyzer technique in range of 10–4000 Hz frequency by depending on the alternating current conductivities. The mode of thermal degradation including formation of the main products of poly(HNPPMA) degraded from ambient temperature to 500 °C was identified. S°, the cold ring fraction (CRF) was collected from room temperature to 500 °C. The structure of the degradation products has also been studied depending on the GC‐MS analysis. The thermal degradation mechanism for poly(HNPPMA) with radical degradation processes thought to dominate at high temperature was proposed based on GC/MS, NMR, FT‐IR, and taking into account the new products and differences in stability. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43925.
Polypyrrole‐wrapped Pd nanoparticles hollow capsules as a catalyst for reduction of 4‐nitroaniline
Authors: Zou Hanzhi , Shang Mengyin , Ren Guohong , Wang Wenqin 
Published: June 2016

ABSTRACTIn this study, by in situ reduction of Pd2+ ions attached on the surface of the sulfonated polystyrene (PS‐SO3H) spheres, complete and dense palladium (Pd) nanoparticles (NPs) layer were deposited around PS‐SO3H spheres. The PS@Pd spheres were wrapped by polypyrrole (PPy) shell, which could avoid escaping of Pd NPs. After selectively etching the PS core, the hollow structures with Pd NPs embedded in PPy capsule shell were obtained. The as‐prepared Pd@PPy hollow capsules showed excellent catalytic activity toward the reduction of 4‐nitroaniline because of the high Pd NPs loading. Furthermore, good reusabilty was demonstrated seven times without any detectible loss in activity. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43933.
Development and characterization of green composites from bio‐based polyethylene and peanut shell
Authors: Garcia‐Garcia Daniel , Carbonell‐Verdu Alfredo , Jordá‐Vilaplana Amparo , Balart Rafael , Garcia‐Sanoguera David 
Published: June 2016

ABSTRACTIn the present work, different compatibilizers, namely polyethylene‐graft‐maleic anhydride (PE‐g‐MA), polypropylene‐graft‐maleic anhydride (PP‐g‐MA), and polystyrene‐block‐poly(ethylene‐ran‐butylene)‐block‐polystyrene‐graft‐maleic anhydride (SEBS‐g‐MA) were used on green composites derived from biobased polyethylene and peanut shell (PNS) flour to improve particle–polymer interaction. Composites of high‐density polyethylene/peanut shell powder (HDPE/PNS) with 10 wt % PNS flour were compatibilized with 3 wt % of the abovementioned compatibilizers. As per the results, PP‐g‐MA copolymer lead to best optimized properties as evidenced by mechanical characterization. In addition, best particle–matrix interface interactions with PP‐g‐MA were observed by scanning electron microscopy (SEM). Subsequently HDPE/PNS composites with varying PNS flour content in the 5–30 wt % range with PP‐g‐MA compatibilizer were obtained by melt extrusion and compounding followed by injection molding and were characterized by mechanical, thermal, and morphological techniques. The results showed that PNS powder, leads to an increase in mechanical resistant properties (mainly, flexural modulus, and strength) while a decrease in mechanical ductile properties, that is, elongation at break and impact absorbed energy is observed with increasing PNS flour content. Furthermore, PNS flour provides an increase in thermal stability due to the natural antioxidant properties of PNS. In particular, composites containing 30 wt % PNS powder present a flexural strength 24% and a flexural modulus 72% higher than the unfilled polyethylene and the thermo‐oxidative onset degradation temperature is increased from 232 °C up to 254 °C thus indicating a marked thermal stabilization effect. Resultant composites can show a great deal of potential as base materials for wood plastic composites. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43940.
Preparation and characterization of the modulus intermediate layer in carbon fiber/epoxy composites by depositing sepiolites
Authors: Yang Qing , Zhang Qingjie , Chen Xin , Deng Xi , Qi Shengli , Sui Gang , He Zhouwen , Lan Fengtao , Wu Dezhen , Yang Xiaoping 
Published: June 2016

ABSTRACTAn important aspect in development of multi‐scale reinforced composites is their mass production which can be easily realized. In this article, the sepiolites (Si12O30Mg8(OH)4(OH2)4·8H2O) are directly deposited onto the surface of JH‐T800 carbon fibers for the first time with no need for removal of the commercial sizing agent. The sepiolites adhering to the carbon fibers are uniformly distributed with random orientation, and participated in the formation of high modulus intermediate layer encompassing the carbon fiber. After the deposition of sepiolites, the interfacial shear strengths (IFSS) of the carbon fiber/epoxy composites are significantly improved as shown in single‐fiber composite fragmentation tests. Compared to the commercial carbon fiber composites, the sepiolite‐deposited fiber composites also exhibit obvious improvement in the interlaminar shear strength and flexural strength. As a new kind of multi‐scale reinforcement with industrial application value, the sepiolite‐deposited carbon fibers can further raise the level of mechanical properties of the existing carbon fiber reinforced composites. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43955.
Statins and Risk of Rheumatoid Arthritis: A Nested Case–Control Study
Authors: Tascilar Koray , Dell'Aniello Sophie , Hudson Marie , Suissa Samy 
Published: June 2016

ObjectiveStatins have antiinflammatory/immunomodulatory effects that may be useful in preventing rheumatoid arthritis (RA), but previous observational studies about the risk of RA with statin use yielded conflicting results. The aim of this study was to determine whether high‐intensity statin treatment is associated with reduced risk of RA.MethodsUsing data from the UK Clinical Practice Research Datalink, we performed a nested case–control analysis in a population‐based cohort of patients who began receiving statins between 1997 and 2009 and were followed up until a first diagnosis of RA, death, end of registration with the physician's practice, or end of January 2011. For each case of RA, 10 age‐, sex‐, and calendar year–matched controls were randomly selected from risk sets. We estimated the hazard ratio (HR) of incident RA in the highest quintile of duration‐weighted average statin intensity compared to the lowest, using conditional logistic regression. Models were adjusted for smoking status, total cholesterol level, obesity, history of cardiovascular disease, coexistent autoimmune disease, hypothyroidism, and persistence with treatment.ResultsThe cohort included 528,654 new users of statins, with 1,357 new cases of RA occurring during a mean follow‐up of 3.3 years, for an incidence rate of 7.9 per 10,000 person‐years. Cases were more likely to be smokers, to have other autoimmune diseases, and to have had lower total cholesterol levels at baseline. The incidence of RA was lower in the highest statin intensity quintile (adjusted HR 0.77 [95% confidence interval 0.63–0.95]) in comparison to the lowest quintile.ConclusionIn this large population‐based study, high‐intensity statin treatment was associated with a reduced risk of RA in comparison to low‐intensity statin treatment.
Prüfung der Standorteignung für Windenergieanlagen: Ein pragmatischer Ansatz
Authors: Rodenhausen Moritz , Moser Wolfgang , Hülsmann Christian , Bergemann Constantin , Könker Michael , McKenna Russell 
Published: June 2016

AbstractDie baurechtlichen Anforderungen an Windenergieanlagen (WEA) in Deutschland verlangen eine Prüfung der Standorteignung für sowohl neue WEA als auch bestehende, benachbarte WEA. Unter Verwendung der bisherigen Verfahren ist es nicht möglich, die Prüfung der Standorteignung für alle WEA durchzuführen, wenn der Windpark aus WEA verschiedener Hersteller besteht. Um die Standorteignung für die bestehenden WEA dennoch zu gewährleisten und den Anforderungen der Behörden Genüge zu tun, werden die neuen WEA zunehmend mit reduzierter Leistung betrieben. Dieser Beitrag stellt eine Erweiterung des bisherigen Verfahrens für die Standorteignung nach DIBt 2012 vor. Aufwändige Lastberechnungen durch die Hersteller können vermieden werden. Das Verfahren kann neben den Herstellern auch durch Dritte angewandt werden, was beispielswiese die Prüfung der Standorteignung durch unabhängige Sachverständige erlaubt.
t‐boc synthesis of huwentoxin‐i through native chemical ligation incorporating a trifluoromethanesulfonic acid cleavage strategy
Authors: Thapa Parashar , Cabalteja Chino C. , Philips Edwin E. , Espiritu Michael J. , Peigneur Steve , Mille Bea G. , Tytgat Jan , Cummins Theodore R. , Bingham Jon‐Paul 
Published: June 2016

AbstractTert‐butyloxycarbonyl (t‐Boc)‐based native chemical ligation (NCL) techniques commonly employ hydrogen fluoride (HF) to create the thioester fragment required for the ligation process. Our research aimed to assess the replacement of HF with Trifluoromethanesulfonic acid (TFMSA). Here we examined a 33 amino acid test peptide, Huwentoxin‐I (HwTx‐I) as a novel candidate for our TFMSA cleavage protocol. Structurally HwTx‐I has an X‐Cys16‐Cys17‐X sequence mid‐region, which makes it an ideal candidate for NCL. Experiments determined that the best yields (16.8%) obtained for 50 mg of a thioester support resin were achieved with a TFMSA volume of 100 μL with a 0.5‐h incubation on ice, followed by 2.0 h at room temperature. RP‐HPLC/UV and mass spectra indicated the appropriate parent mass and retention of the cleaved HwTx‐I N‐terminal thioester fragment (Ala1‐Cys16), which was used in preparation for NCL. The resulting chemically ligated HwTx‐I was oxidized/folded, purified, and then assessed for pharmacological target selectivity. Native‐like HwTx‐I produced by this method yielded an EC50 value of 340.5 ± 26.8 nM for Nav1.2 and an EC50 value of 504.1 ± 81.3 nM for Nav1.3, this being similar to previous literature results using native material. This article represents the first NCL based synthesis of this potent sodium channel blocker. Our illustrated approach removes potential restrictions in the advancement of NCL as a common peptide laboratory technique with minimal investment, and removes the hazards associated with HF usage. © 2016 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 737–745, 2016.
Copy‐number variation of MCL1 predicts overall survival of non‐small‐cell lung cancer in a Southern Chinese population
Authors: Yin Jieyun , Li Yangkai , Zhao Hao , Qin Qin , Li Xiaorong , Huang Jiao , Shi Yun , Gong Shufang , Liu Li , Fu Xiangning , Nie Shaofa , Wei Sheng 
Published: June 2016

AbstractBCL2L1 and MCL1 are key anti‐apoptotic genes, and critical for cancer progression. The prognostic values of BCL2L1 and MCL1 copy‐number variations (CNVs) in non‐small‐cell lung cancer (NSCLC) remain largely unknown. Somatic CNVs in BCL2L1 and MCL1 genes were tested in tumor tissues from 516 NSCLC patients in southern China; afterward, survival analyses were conducted with overall survival (OS) as outcome. Additionally, the associations between CNVs and mRNA expression levels were explored using data from 986 NSCLC patients in the Cancer Genome Atlas project. It was found that amplifications of BCL2L1 and MCL1 were associated with unfavorable OS of NSCLC, with adjusted hazards ratio of 1.62 (95% confident interval [CI] = 1.10–2.40; P = 0.015) and 1.39 (95% CI = 1.05–1.84; P = 0.020), respectively. Amplifications of MCL1, but not BCL2L1, were related with higher mRNA expression levels of corresponding gene, compared with non‐amplifications (P = 0.005). Interestingly, after incorporating with MCL1 CNV status, clinical variables (age, sex, TNM stage, and surgical approach) showed an improved discriminatory ability to classify OS (area under curve increased from 72.2% to 74.1%; P = 0.042, DeLong's test). Overall, MCL1 CNV might be a prognostic biomarker for NSCLC, and additional investigations are needed to validate our findings.
Bioactive Secondary Metabolites from Schizogyne sericea (Asteraceae) Endemic to Canary Islands
Authors: Venditti Alessandro , Bianco Armandodoriano , Muscolo Camilla , Zorzetto Christian , Sánchez‐Mateo Candelaria C. , Rabanal Rosa M. , Quassinti Luana , Bramucci Massimo , Damiano Silvia , Iannarelli Romilde , Lupidi Giulio , Papa Fabrizio , Petrelli Dezemona , Vitali Luca A. , Vittori Sauro , Maggi Filippo 
Published: June 2016

Schizogyne sericea (Asteraceae) is a halophytic shrub endemic to the Canary Islands and traditionally employed as analgesic, astringent, anti‐inflammatory, and vulnerary. A comprehensive phytochemical investigation was conducted on the flowering aerial parts by analyzing both essential oil constituents and polar compounds. The essential oil was dominated by p‐cymene, with the noteworthy occurrence of β‐pinene and thymol esters. From the EtOH extract, eight compounds were isolated and structurally elucidated. Essential oil, polar fractions, and isolates (2), (4), and (5) were separately in vitro assayed for antiproliferative activity on human tumor cell lines (A375, MDA‐MB 231, and HCT116) by MTT assay, for antioxidant potential by DPPH, ABTS, and FRAP assays, and for antimicrobial activity by the agar disk diffusion method. Results revealed that essential oil and compounds 1 and 2 exert a strong inhibition on tumor cells, and in some cases, higher than that of cisplatin. Fractions containing thymol derivatives (1 and 2) and caffeoylquinic acid derivatives 4 and 5 displayed antioxidant activity comparable to that of Trolox, making S. sericea extract an interesting natural product with potential applications as preservative or in the treatment of diseases in which oxidative stress plays an important role.
Molecular Phylogeny, Diversity, and Bioprospecting of Endophytic Fungi Associated with wild Ethnomedicinal North American Plant Echinacea purpurea (Asteraceae)
Authors: Carvalho Camila R. , Wedge David E. , Cantrell Charles L. , Silva‐Hughes Alice F. , Pan Zhiqiang , Moraes Rita M. , Madoxx Victor L. , Rosa Luiz H. 
Published: June 2016

The endophytic fungal community associated with the ethnomedicinal plant Echinacea purpurea was investigated as well as its potential for providing antifungal compounds against plant pathogenic fungi. A total of 233 endophytic fungal isolates were obtained and classified into 42 different taxa of 16 genera, of which Alternaria alternata, Colletotrichum dematium, and Stagonosporopsis sp. 2 are the most frequent colonizers. The extracts of 29 endophytic fungi displayed activities against important phytopathogenic fungi. Eight antifungal extracts were selected for chemical analysis. Forty fatty acids were identified by gas chromatography‐flame‐ionization detection (GC‐FID) analysis. The compounds (–)‐5‐methylmellein and (–)‐(3R)‐8‐hydroxy‐6‐methoxy‐3,5‐dimethyl‐3,4‐dihydroisocoumarin were isolated from Biscogniauxia mediterraneaEPU38CA crude extract. (–)‐5‐Methylmellein showed weak activity against Phomopsis obscurans, P. viticola, and Fusarium oxysporum, and caused growth stimulation of C. fragariae, C. acutatum, C. gloeosporioides, and Botrytis cinerea. (–)‐(3R)‐8‐Hydroxy‐6‐methoxy‐3,5‐dimethyl‐3,4‐dihydroisocoumarin appeared slightly more active in the microtiter environment than 5‐methylmellein. Our results indicate that E. purpurea lives symbiotically with different endophytic fungi, which are able to produce bioactive fatty acids and aromatic compounds active against important phytopathogenic fungi. The detection of the different fatty acids and aromatic compounds produced by the endophytic community associated with wild E. purpurea suggests that it may have intrinsic mutualistic resistance against phytopathogen attacks in its natural environment.
Geographically Related Variation in Epicuticular Wax Traits of Pinus nigra Populations from Southern Carpathians and Central Balkans – Taxonomic Considerations
Authors: Mitić Zorica S. , Zlatković Bojan K. , Jovanović Snežana Č. , Stojanović Gordana S. , Marin Petar D. 
Published: June 2016

The chemical composition of epicuticular waxes of nine populations from three Pinus nigra J. F. Arnold subspecies (namely subsp. nigra, subsp. banatica (Borbás) Novák, and subsp. pallasiana (Lamb.) Holmboe) from Southern Carpathians and central Balkan Peninsula were analyzed using GC/MS and GC/FID chromatography, and multivariate statistical techniques with respect to biogeography and taxonomy. In the needle waxes, four primary alcohols and 14 n‐alkanes ranging from C21 to C33 were identified, and the most abundant compounds were the four odd‐numbered n‐alkanes C27, C25, C23, and C29. Multivariate statistical analyses (CDA and CA) have shown existence of three P. nigra groups and suggested clinal differentiation as a mechanism of genetic variation across a geographic area: the first group consisted of the southernmost populations of subsp. pallasiana from Macedonia, the second consisted of the northernmost subsp. banatica populations from Romania, while all populations in Serbia described as three different subspecies (nigra, banatica, and pallasiana) formed the third group together with subsp. nigra population from Bosnia and Herzegovina. According to simple linear regression, geographic latitude and four bioclimatic parameters were moderately correlated with the contents of epicuticular wax compounds that are important in population discrimination, while stepwise multiple regression showed that latitude participated in most of the regression models for predicting the composition of the epicuticular waxes. These results agree with CDA and CA analysis, and confirmed the possibility of recognition of fine geographic differentiation of the analyzed P. nigra populations.
Stereospecific Effects of Oxygen‐to‐Sulfur Substitution in DNA Phosphate on Ion Pair Dynamics and Protein–DNA Affinity
Authors: Nguyen Dan , Zandarashvili Levani , White Mark A. , Iwahara Junji 
Published: June 2016

AbstractOxygen‐to‐sulfur substitutions in DNA phosphate often enhance affinity for DNA‐binding proteins. Our previous studies have suggested that this effect of sulfur substitution of both OP1 and OP2 atoms is due to an entropic gain associated with enhanced ion pair dynamics. In this work, we studied stereospecific effects of single sulfur substitution of either the OP1 or OP2 atom in DNA phosphate at the Lys57 interaction site of the Antennapedia homeodomain–DNA complex. Using crystallography, we obtained structural information on the RP and SP diastereomers of the phosphoromonothioate and their interaction with Lys57. Using fluorescence‐based assays, we found significant affinity enhancement upon sulfur substitution of the OP2 atom. Using NMR spectroscopy, we found significant mobilization of the Lys57 side‐chain NH3+ group upon sulfur substitution of the OP2 atom. These data provide further mechanistic insights into the affinity enhancement by oxygen‐to‐sulfur substitution in DNA phosphate.
Branched Tungsten Oxide Nanorod Arrays Synthesized by Controlled Phase Transformation for Solar Water Oxidation
Authors: Zhang Tao , Wang Lu , Su Jinzhan , Guo Liejin 
Published: June 2016

AbstractBranched (NH4)0.33⋅WO3 nanorods have been successfully synthesized by applying a simple hydrothermal approach with ammonium oxalate as capping agents. After annealing them in different atmospheres, the (NH4)0.33⋅WO3 nanorods were converted to WO3 nanorods. Atmosphere‐dependent morphology evolution and phase transformation by annealing of (NH4)0.33⋅WO3 were observed. The branched WO3 nanorods produce a higher photoelectrochemical activity than the bare WO3 nanorods without branches obtained under similar conditions, and the improvement of efficiency by branched nanorods was ascribed to the better light‐trapping characteristics and increase in surface area, which facilitates holes transfer at the WO3/electrolyte interface. The possible formation mechanisms of branched nanorods have been explored and the results show that the synergistic interaction between ammonium ion (NH4+) and acetate ion (−COO−) contributes to the formation of branched (NH4)0.33⋅WO3 nanorods.