bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving Cellulose Dissolution in Ionic Liquids by Tuning the Size of the Ions: Impact of the Length of the Alkyl Chains in Tetraalkylammonium Carboxylate
Authors: Meng Xiangqian , Devemy Julien , Verney Vincent , Gautier Arnaud , Husson Pascale , Andanson Jean‐Michel
Published: January 2017

Twenty ionic liquids based on tetraalkylammonium cations and carboxylate anions have been synthesized, characterized, and tested for cellulose dissolution. The amount of cellulose dissolved in these ionic liquids depends strongly on the size of the ions: from 0 to 22 wt % cellulose can be dissolved at 90 °C. The best ionic liquids are less viscous and ammonium carboxylate based ionic liquids can dissolve as much as imidazolium‐based ones. The viscosity of an ionic liquid can be decreased by the addition of DMSO as a cosolvent. After the addition of cosolvent, similar amounts of cellulose per ions are reached for most ionic liquids. As observed by rheology, ionic liquids with the longest alkyl chains form a gel when a high amount of cellulose is dissolved; this drastically limits their potential. Molecular simulations and IR spectroscopy have also been used with the aim of understanding how molecular interactions differ between efficient and inefficient ionic liquids.
Reliable Performance Characterization of Mediated Photocatalytic Water‐Splitting Half Reactions
Authors: Han Lihao , Lin Meng , Haussener Sophia
Published: January 2017

Photocatalytic approaches using two sets of semiconductor particles and a pair of redox‐shuttle mediators are considered as a safe and economic solution for solar water splitting. Here, accurate experimental characterization techniques for photocatalytic half reactions are reported, investigating the gas as well as the liquid products. The methods are exemplified utilizing photocatalytic titania particles in an iron‐based aqueous electrolyte for effective oxygen evolution and mediator reduction reactions under illumination. Several product characterization methods, including an optical oxygen sensor, pressure sensor, gas chromatography, and UV/Vis spectroscopy are used and compared for accurate, high‐resolution gas‐products and mediator conversion measurements. Advantages of each technique are discussed. A high Faraday efficiency of 97.5±2 % is calculated and the reaction rate limits are investigated.
Heterogeneous tempo and mode of evolutionary diversification of compounds in lizard chemical signals
Authors: García‐Roa Roberto , Jara Manuel , López Pilar , Martín José , Pincheira‐Donoso Daniel
Published: January 2017

Important part of the multivariate selection shaping social and interspecific interactions among and within animal species emerges from communication. Therefore, understanding the diversification of signals for animal communication is a central endeavor in evolutionary biology. Over the last decade, the rapid development of phylogenetic approaches has promoted a stream of studies investigating evolution of communication signals. However, comparative research has primarily focused on visual and acoustic signals, while the evolution of chemical signals remains largely unstudied. An increasing interest in understanding the evolution of chemical communication has been inspired by the realization that chemical signals underlie some of the major interaction channels in a wide range of organisms. In lizards, in particular, chemosignals play paramount roles in female choice and male–male competition, and during community assembly and speciation. Here, using phylogenetic macro‐evolutionary modeling, we show for the very first time that multiple compounds of scents for communication in lizards have diversified following highly different evolutionary speeds and trajectories. Our results suggest that cholesterol, α‐tocopherol, and cholesta‐5,7‐dien‐3‐ol have been subject to stabilizing selection (Ornstein–Uhlenbeck model), whereas the remaining compounds are better described by Brownian motion modes of evolution. Additionally, the diversification of the individual compounds has accumulated substantial relative disparity over time. Thus, our study reveals that the chemical components of lizard chemosignals have proliferated across different species following compound‐specific directions.
Impacts of leaf age and heat stress duration on photosynthetic gas exchange and foliar nonstructural carbohydrates in Coffea arabica
Authors: Marias Danielle E. , Meinzer Frederick C. , Still Christopher
Published: January 2017

Given future climate predictions of increased temperature, and frequency and intensity of heat waves in the tropics, suitable habitat to grow ecologically, economically, and socially valuable Coffea arabica is severely threatened. We investigated how leaf age and heat stress duration impact recovery from heat stress in C. arabica. Treated plants were heated in a growth chamber at 49°C for 45 or 90 min. Physiological recovery was monitored in situ using gas exchange, chlorophyll fluorescence (the ratio of variable to maximum fluorescence, FV/FM), and leaf nonstructural carbohydrate (NSC) on mature and expanding leaves before and 2, 15, 25, and 50 days after treatment. Regardless of leaf age, the 90‐min treatment resulted in greater FV/FM reduction 2 days after treatment and slower recovery than the 45‐min treatment. In both treatments, photosynthesis of expanding leaves recovered more slowly than in mature leaves. Stomatal conductance (gs) decreased in expanding leaves but did not change in mature leaves. These responses led to reduced intrinsic water‐use efficiency with increasing heat stress duration in both age classes. Based on a leaf energy balance model, aftereffects of heat stress would be exacerbated by increases in leaf temperature at low gs under full sunlight where C. arabica is often grown, but also under partial sunlight. Starch and total NSC content of the 45‐min group significantly decreased 2 days after treatment and then accumulated 15 and 25 days after treatment coinciding with recovery of photosynthesis and FV/FM. In contrast, sucrose of the 90‐min group accumulated at day 2 suggesting that phloem transport was inhibited. Both treatment group responses contrasted with control plant total NSC and starch, which declined with time associated with subsequent flower and fruit production. No treated plants produced flowers or fruits, suggesting that short duration heat stress can lead to crop failure.
Functional consequences of plant‐animal interactions along the mutualism‐antagonism gradient
Authors: Rodríguez‐Rodríguez María C. , Jordano Pedro , Valido Alfredo
Published: January 2017

Plant‐animal interactions are pivotal for ecosystem functioning, and usually form complex networks involving multiple species of mutualists as well as antagonists. The costs and benefits of these interactions show a strong context‐dependency directly related to individual variation in partner identity and differential strength. Yet understanding the context‐dependency and functional consequences of mutualistic and antagonistic interactions on individuals remains a lasting challenge. We use a network approach to characterize the individual, plant‐based pollination interaction networks of the Canarian Isoplexis canariensis (Plantaginaceae) with a mixed assemblage of vertebrate mutualists (birds and lizards) and invertebrate antagonists (florivores, nectar larcenists, and predispersal seed predators). We identify and quantify interaction typologies based on the sign (mutualistic vs. antagonistic) and strength (weak vs. strong) of animal‐mediated pollination and test the relationship with individual female reproductive success (FRS). In addition, we document pollinator movement patterns among individual plants to infer events of pollen transfer/receipt that define the plant mating networks and test the relationship with FRS. We identify six interaction typologies along a mutualism‐antagonism gradient, with two typologies being over‐represented involving both mutualists and antagonists and influencing FRS. Plants showing strong mutualistic interactions, but also (weak or strong) interactions with antagonists are relatively better connected in the mating network (i.e., with higher potential to transfer or receive pollen). Thus, mixed flower visitor assemblages with mutualists and antagonists give plants increased their importance in the mating networks, promote outcrossing and increasing both female and male fitness. Our approach helps characterize plant‐animal interaction typologies, the context‐specificity of diversified mutualisms, and a better forecasting of their functional consequences.
Shared biomarkers between female diastolic heart failure and pre‐eclampsia: a systematic review and meta‐analysis
Authors: Alma Lisa J. , Bokslag Anouk , Maas Angela H.E.M. , Franx Arie , Paulus Walter J. , de Groot Christianne J.M.
Published: January 2017

Evidence accumulates for associations between hypertensive pregnancy disorders and increased cardiovascular risk later. The main goal of this study was to explore shared biomarkers representing common pathogenic pathways between heart failure with preserved ejection fraction (HFpEF) and pre‐eclampsia where these biomarkers might be potentially eligible for cardiovascular risk stratification in women after hypertensive pregnancy disorders. We sought for blood markers in women with diastolic dysfunction in a first literature search, and through a second search, we investigated whether these same biochemical markers were present in pre‐eclampsia.This systematic review and meta‐analysis presents two subsequent systematic searches in PubMed and EMBASE. Search I yielded 3014 studies on biomarkers discriminating women with HFpEF from female controls, of which 13 studies on 11 biochemical markers were included. Cases had HFpEF, and controls had no heart failure. The second search was for studies discriminating women with pre‐eclampsia from women with non‐hypertensive pregnancies with at least one of the biomarkers found in Search I. Search II yielded 1869 studies, of which 51 studies on seven biomarkers were included in meta‐analyses and 79 studies on 12 biomarkers in systematic review.Eleven biological markers differentiated women with diastolic dysfunction from controls, of which the following 10 markers differentiated women with pre‐eclampsia from controls as well: C‐reactive protein, HDL, insulin, fatty acid‐binding protein 4, brain natriuretic peptide, N terminal pro brain natriuretic peptide, adrenomedullin, mid‐region pro adrenomedullin, cardiac troponin I, and cancer antigen 125.Our study supports the hypothesis that HFpEF in women shares a common pathogenic background with pre‐eclampsia. The biomarkers representing inflammatory state, disturbances in myocardial function/structure, and unfavourable lipid metabolism may possibly be eligible for future prognostic tools.
A multimarker multi‐time point‐based risk stratification strategy in acute heart failure: results from the RELAX‐AHF trial
Authors: Demissei Biniyam G. , Cotter Gad , Prescott Margaret F. , Felker G. Michael , Filippatos Gerasimos , Greenberg Barry H. , Pang Peter S. , Ponikowski Piotr , Severin Thomas M. , Wang Yi , Qian Min , Teerlink John R. , Metra Marco , Davison Beth A. , Voors Adriaan A.
Published: January 2017

Aims

We evaluated the added prognostic value of a multi‐time point‐based multimarker panel of biomarkers in patients with acute heart failure (AHF).

Methods and results

Seven circulating biomarkers [NT‐proBNP, high sensitivity cardiac troponin T (hs‐cTnT), soluble ST2 (sST2), growth differentiation factor 15 (GDF‐15), cystatin‐C, galectin‐3, and high sensitivity C‐reactive protein (hs‐CRP)] were measured at baseline and on days 2, 5, 14, and 60 in 1161 patients enrolled in the RELAX‐AHF trial. Patients with BNP ≥350 ng/L or NT‐proBNP ≥1400 ng/L, mild to moderate renal impairment, and systolic blood pressure >125 mmHg were included in the trial. Time‐dependent Cox regression analysis was utilized to evaluate the incremental value of serial measurement of biomarkers. Added value of individual biomarkers and their combination, on top of a pre‐specified baseline model, was quantified with the gain in the C‐index. Serial biomarker evaluation showed incremental predictive value over baseline measurements alone for the prediction of 180‐day cardiovascular mortality except for galectin‐3. While a repeat measurement as early as day 2 was adequate for NT‐proBNP and cystatin‐C in terms of maximizing discriminatory accuracy, further measurements on days 14 and 60 provided added value for hs‐cTnT, GDF‐15, sST2, and hs‐CRP. Individual biomarker additions on top of the baseline model showed additional prognostic value. The greatest prognostic gain was, however, attained with the combination of NT‐proBNP, hs‐cTnT, GDF‐15, and sST2, which yielded 0.08 unit absolute increment in the C‐index to 0.87 (95% confidence interval 0.83–0.91].

Conclusion

In patients with AHF and mild to moderate renal impairment, a multimarker approach based on a panel of serially evaluated biomarkers provides the greatest prognostic improvement unmatched by a single time point‐based single marker strategy.
A comparative study of ex vivo skin optical clearing using two‐photon microscopy
Authors: Sdobnov Anton , Darvin Maxim E. , Lademann Juergen , Tuchin Valery
Published: January 2017

Multiphoton tomography (MPT) is a prospective tool for imaging the skin structure. Aiming to increase the probing depth, a comparative ex vivo study of optical clearing of porcine ear skin was performed by using two optical clearing agents (OCAs), i.e., glycerol and iohexol (OmnipaqueTM) at different concentrations, which exhibit different osmotic properties. The results show that a topical application of glycerol or OmnipaqueTM solutions onto the skin for 60 min significantly improved the depth and contrast of the MPT signals. By utilizing 40%, 60% and 100% glycerol, and 60% and 100% OmnipaqueTM it was demonstrated that both agents improve autofluorescence and SHG (second harmonic generation) signals from the skin. At the applied concentrations and agent time exposure, glycerol is more effective than OmnipaqueTM. However, tissue shrinkage and cell morphology changes were found for highly concentrated glycerol solutions. OmnipaqueTM, on the contrary, increases the safety and has no or minimal tissue shrinkage during the optical clearing process. Moreover OmnipaqueTM allows for robust multimodal optical/X‐ray imaging with automatically matched optically cleared and X‐ray contrasted tissue volumes. These findings make OmnipaqueTM more prospective than glycerol for some particular application.

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SOCIAL DEVELOPMENT ASSETS AND LAW‐ABIDINGNESS AMONG URBAN ADOLESCENTS: IMPLICATIONS FOR POSITIVE YOUTH DEVELOPMENT
Authors: Drinkard Allyson M. , Estevez Nicolle , Adams Richard E.
Published: January 2017

In this study, we argue that researchers should look to prevention efforts that capitalize on youth’s potential for positive development and law‐abidingness in order to develop interventions that facilitate their successful transition to young adulthood. We draw from the positive youth development framework to assess the association between individual, family, and community assets and law‐abidingness among a sample of adolescents living in Chicago, Illinois, neighborhoods. Data come from the first wave of the Program on Human Development in Chicago Neighborhoods (N = 1,258). We focus on cohorts 12 and 15, since developmental assets have a significant impact on adolescents during these ages. After controlling for a range of individual and demographic variables, we find that greater levels of positive family communication were associated with greater odds of law‐abidingness in our multilevel logistic regression models. The findings of this study are discussed in the context of a sociological perspective on positive youth development.
Effect of chloride and nitrate salts on Hg(II) sorption by raw and pyrolyzed malt spent rootlets
Authors: Boutsika Lamprini G , Karapanagioti Hrissi K , Manariotis Ioannis D
Published: January 2017

BACKGROUND

Mercury is considered to be one of the most harmful metals for human health and the environment. Biomass based materials and the corresponding biochars show promising potential as Hg(II) sorbents. Sorption is an effective process to remove Hg(II) from polluted waters, and is mainly affected by water chemistry. The sorption efficiency of malt spent rootlets and their biochar was evaluated at various ionic strength levels with two different salts, NaCl and NaNO3.

RESULTS

For both materials, the salts were added at concentrations of 1, 0.5, 0.1, 0.01, and 0.001 mol L−1. At pH 5, Hg(II) removal was not significantly affected by the presence of NaNO3. High Hg(II) removal was obtained even at high NaNO3 concentrations; 53% at 1 mol L−1 NaNO3. A significant decrease of Hg(II) sorption was observed with the increase of NaCl concentration. Hg(II) removal was 55% and 20% at 1 mmol L−1 and 1 mol L−1 NaCl, respectively.

CONCLUSIONS

The differences observed in salinity effect can be related to the different counter ions present in the salts. Low Cl− or NO3− concentrations did not interfere strongly with mercury sorption, but excess Cl− formed mercury species with negative charge, which demonstrated lower sorption. © 2017 Society of Chemical Industry
Dendrimers for fluorescence‐based bioimaging
Authors: Trzepiński Przemysław , Klajnert‐Maculewicz Barbara
Published: January 2017

Dendrimer science is a relatively new branch of nanotechnology focused on non‐linear macromolecules called dendrimers. These hyperbranched polymers are characterized by monodispersity, highly defined structure and – depending on specific type of dendrimer – good biocompatibility. Due to the possibility of encapsulation or surface conjugation of guest molecules on a dendrimer it can serve as delivery agent in life sciences. For bioimaging based on fluorescence dendritic polymers were extensively studied as conventional fluorophore carriers. Complexing of organic dyes with these macromolecules improves their solubility and enhances cellular uptake. Moreover, it helps overcome other limitations in using them for photobleaching, and their lack of specificity or cytotoxicity. Protective properties of dendrimers are especially valuable for use with quantum dots, which have great optical potential but contain heavy metals that can adversely affect biological objects. Dendrimer based fluorescent probes have been widely applied in vitro and in vivo bioimaging. An interesting phenomenon is non‐traditional intrinsic fluorescence (NTIF) of dendrimers. Some of them show pH‐ and oxygen‐dependent fluorescence without conjugation with other particles. NTIF is not fully understood, but attempts to take advantage of it for bioimaging have been made. This phenomenon has great potential since it enables dendrimers to serve simultaneously as delivery and diagnostic tool. © 2017 Society of Chemical Industry
Distal pancreatectomy for benign and low grade malignant tumors: Short‐term postoperative outcomes of spleen preservation—A systematic review and update meta‐analysis
Authors: Pendola Fiorella , Gadde Rahul , Ripat Caroline , Sharma Rishika , Picado Omar , Lobo Laila , Sleeman Danny , Livingstone Alan S. , Merchant Nipun , Yakoub Danny
Published: January 2017

Background

The value of spleen preservation with distal pancreatectomy (DP) for benign and low grade malignant tumors remains unclear. The aim of this study was to evaluate the short‐term postoperative clinical outcomes in patients undergoing DP with splenectomy (DPS) or spleen preservation (SPDP).

Methods

Online database search was performed (2000 to present); key bibliographies were reviewed. Studies comparing patients undergoing DP with either DPS or SPDP, and assessing postoperative complications were included.

Results

Meta‐analysis of included data showed SPDP patients had significantly less operative blood loss, shorter duration of hospitalization, lower incidence of fluid collection and abscess, lower incidence of postoperative splenic and portal vein thrombosis, and lower incidence of new onset postoperative diabetes. For the whole group, there was no difference in incidence of postoperative pancreatic fistula (POPF) (RR = 0.95; 95%CI 0.65–1.40, P = 0.80), however, subgroup analysis of studies using ISGPF criteria showed that DPS patients had increased rates of Grade B/C POPF (RR = 1.35; 95%CI 1.08–1.70, P = 0.01).

Conclusions

SPDP for benign and low grade malignant tumors is associated with shorter hospital stay and decreased morbidity compared to DPS. J. Surg. Oncol. 2017;115:137–143. © 2017 Wiley Periodicals, Inc.
Carbon monoxide ameliorates hepatic ischemia/reperfusion injury via sirtuin 1‐mediated deacetylation of high‐mobility group box 1 in rats
Authors: Sun Jian , Guo Enshuang , Yang Jiankun , Yang Yan , Liu Shenpei , Hu Jifa , Jiang Xiaojing , Dirsch Olaf , Dahmen Uta , Dong Wei , Liu Anding
Published: January 2017

Carbon monoxide (CO) exerts protective effects on hepatic ischemia/reperfusion injury (IRI), but the underlying molecular mechanisms are not fully understood. High‐mobility group box 1 (HMGB1) is an important mediator of injury and inflammation in hepatic IRI. Here, we investigated whether CO could attenuate hepatic IRI via inhibition of HMGB1 release, particularly through sirtuin 1 (SIRT1). CO was released by treatment with carbon monoxide–releasing molecule (CORM)–2. CORM‐2–delivered CO ameliorated hepatic IRI, as indicated by lower serum aminotransferase levels, lower hepatic inflammatory responses, and less severe ischemia/reperfusion‐associated histopathologic changes. Treatment with CORM‐2 significantly inhibited IRI‐induced HMGB1 translocation and release. SIRT1 expression was increased by CORM‐2 pretreatment. When CORM‐2–induced SIRT1 expression was inhibited using EX527, HMGB1 translocation and release were increased and hepatic IRI was worsened, whereas SIRT1 activation by resveratrol reversed this trend. In vitro, CORM‐2 reduced hypoxia/reoxygenation–induced HMGB1 translocation and release, these inhibitions were blocked by SIRT1 inhibition using EX527 or SIRT1 small interfering RNA both in alpha mouse liver 12 cells and RAW264.7 macrophages. Moreover, SIRT1 directly interacted with and deacetylated HMGB1. IRI increased HMGB1 acetylation, which was abolished by CORM‐2 treatment via SIRT1. In conclusion, these results suggest that CO may increase SIRT1 expression, which may decrease HMGB1 acetylation and subsequently reduce its translocation and release, thereby protecting against hepatic IRI. Liver Transplantation 23 510–526 2017 AASLD.
Effect of surface treatment on the bioactivity and electrochemical behavior of magnesium alloys in simulated body fluid
Authors: Sasikumar Y. , Solomon M. M. , Olasunkanmi L. O. , Ebenso E. E.
Published: January 2017

The effect of surface treatment using NaOH or H2O2 on the bioactivity and corrosion behavior of AZX310, AZ91D, AM50, and AZ31 Mg alloys in simulated body fluid (SBF) has been studied with the aid of surface morphological assessment, in vitro characterization, and electrochemical measurements. The influence of immersion time on the behavior of the treated alloys in SBF was also investigated. X‐ray diffraction (XRD) and scanning electron microscopy (SEM) analyses confirmed successful surface modification upon treatment of alloy surface with NaOH and H2O2. XRD and SEM analyses also revealed that surface modification enhances formation and growth of hydroxyapatite (HA). Formation of HA layer on the alloy surface was further confirmed by Fourier transform infrared spectroscopy analysis. In vitro immersion test reveals that pH of SBF solution containing treated alloys is lower than that containing untreated alloy. However, pH increases with immersion time. Results from weight loss and electrochemical measurements indicate that treated alloys possess higher corrosion resistance in SBF than the untreated ones. H2O2 treated alloys demonstrated greater corrosion resistance in SBF than NaOH treated alloys.
Insights into the corrosion perforation of UNS S32205 duplex stainless steel weld in gas transportation pipelines
Authors: Yuan J.‐T. , Zhang H.‐H. , Fu A.‐Q. , Yin C.‐X. , Zhu M. , Lv N.‐X. , Xu X.‐Q. , Miao J.
Published: January 2017

Microstructure and pitting corrosion resistance of UNS S32205 DSS weld were systematically studied, and its failure causes were analyzed carefully. The results showed the uneven metallographic microstructures with majority of austenite in the HAZ and then the significantly reduced pitting corrosion resistance of the weld. Furthermore, large potential difference between the both sides of the insulation joint and high salinity of the formation water in the pipeline make the leakage current preferably flow out from the weld and enter the transmission fluid, so localized corrosion happens at the inner surface of the weld and leads to the corrosion perforation eventually.
Characterization and protective performance of acrylic‐based nanocomposite coating reinforced with silica nanoparticles
Authors: Bozorg M. , Ramezani A.
Published: January 2017

Acrylic coatings were modified by adding silica nanoparticles to obtain transparent, non‐yellowing and chemically stable coatings, having also good corrosion resistance. Low carbon steel sheets were used as substrate. Pre‐formed nano‐silica particles, prepared by sol‐gel chemistry from methyltriethoxysilane (MTES) and methacryloxypropyltrimethoxysilane (MPTMS) precursors, were dispersed into acrylic resin matrix. Unfilled coating was also produced for comparison. The uniformity of the coatings and the dispersion of nanoparticles in the polymeric matrix were investigated using transmission electron microscopy (TEM) and atomic force microscopy (AFM). The performance of the coatings was evaluated in terms of their UV resistance, optical properties, and corrosion resistance. The corrosion protection performance of the coatings was evaluated using potentiodynamic polarization technique and electrochemical impedance spectroscopy (EIS) in 3.5 wt% NaCl solution at room temperature. TEM studies indicate that silica nanoparticles were homogeneously dispersed through the polymer matrix. The polarization curves, corrosion resistance as measured by the Nyquist plots as well as salt spray tests suggest that the acrylic coating with homogeneously‐dispersed nanoparticles offer the best protection against corrosion.
Triphenylamine Based Random Copolymers: The Effect of Molecular Weight on Performance of Solar Cell and Optoelectronic Properties
Authors: Goker Seza , Hacioglu Serife O. , Hizalan Gonul , Aktas Ece , Cirpan Ali , Toppare Levent
Published: January 2017

Two low band gap triphenylamine based random copolymers are synthesized via Pd‐catalyzed Stille polycondensation reaction to investigate the role of molecular weight on device performance and optoelectronic properties. 1H NMR spectroscopy, UV−vis absorption spectroscopy, cyclic voltammetry, and gel permeation chromatography (GPC) are used for characterization of polymers. The polymerization conditions are optimized to achieve high molecular weight polymers with enhanced optoelectronic properties. PBTP1 reveals broad absorption in the wavelength range of 300–670 nm whereas PBTP2 has absorption in the wavelength range of 300–660 nm. Highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels are calculated as −5.43 and −3.20 eV for PBTP1 and −5.33 and −3.02 eV for PBTP2. The photovoltaic device containing donor PBTP1 and acceptor PCBM[70] in 1:3 weight ratio reveals the highest power conversion efficiency of 2.27%, with Voc of 0.63 V, Jsc of 8.19 mA cm−2, and fill factor of 44% under illumination of AM 1.5 G, 100 mW cm−2. Organic photovoltaics (OPV) cells fabricated with PBTP2 demonstrate improved photovoltaic results due to higher molecular weight and enhanced optoelectronic properties. Photon‐to‐current efficiency of 3.65% with a current density of 14.73 mA cm−2, Voc of 0.69 V, and fill factor of 36% are obtained.

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Fabrication of Super Extensible and Highly Tough Graphene Composite Hydrogels by Thermal Treatment Strategy for the Mixture of Tannin and Graphene Oxide
Authors: Guo Qihua , Shi Zixing , Xu Hongjie , Ma Xiaodong , Yin Jie , Tian Ming
Published: January 2017

Inspired by using the condensed tannins as coinitiator and crosslinker to prepare stretchable hydrogel (TIC‐gel) and by tannins' ability to prepare tannins‐reduced graphene oxide (TGO) at 80 °C, this paper designs a simple and effective method with a thermal treatment process for the mixture of tannin and graphene oxide (GO) to prepare super extensible TGO composite TIC‐gel (TGO‐gel). After the thermal treatment process, graphene oxide is reduced by tannin and its surface becomes orderly which leads to strong π–π stacking interaction between tannins and graphene sheets. By this way, the interaction between graphene sheets and polymer chains is improved. As a result, these composite hydrogels have high tensile strength (0.5–1.2 MPa) and extremely high elongations (3100–4800%) which are much higher than those of GO composites TIC‐gel (TA/GO‐gel) without thermal‐treated process and those of normal graphene composite hydrogel.

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Tensile Behavior of a Substituted Poly(m‐,p‐phenylene) versus Its Parent Counterpart and Synthesis of Related Polyarylenes
Authors: Deffner Bernd , Jimaja Sètuhn , Kroeger Anja , Schlüter A. Dieter
Published: January 2017

In a recent report, a poly(m,p‐phenylene) with acid‐cleavable trialkylsilyl side chains is synthesized by Suzuki polycondensation in a molecular weight of Mw = 300 kDa determined by gel permeation chromatography (GPC). Such a high value suggests this polymer as a potentially attractive material for strong films and fibers both in the presence and absence of the side chains. After confirming these molecular weights by static light scattering, the polymer is processed into thin films for tensile stress measurements. Above the glass transition, thus >180 °C, the material shows an extended plasticity, which is used to obtain elongated samples of draw ratios ranging from 1.5 to 6. The elongated samples show a Young's modulus of up to 5 GPa and a yield strength of 140 MPa. Upon removal of the solubilizing side chains, these values further increase to a Young's modulus of 7.5 GPa in the direction of drawing and a maximum strength of 300 MPa. Motivated by these findings, the scope of this polymer class is broadened by synthesizing two new high molecular weight poly(m,p‐phenylene)s. The structural variation allows to tune the glass transition temperatures between 125 and 240 °C depending on the amount of the meta connected phenylene units.

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Evaluation of interactions between compatibilizers and photostabilizers in coir fiber reinforced polypropylene composites
Authors: Staffa Lucas H. , Agnelli José Augusto M. , de Souza Miguel L. , Bettini Sílvia H. P.
Published: January 2017

Coir fiber‐reinforced polypropylene composites (PP/CF), compatibilized with maleic anhydride grafted polypropylene (PPMAH) and stabilized with a hindered amine, HALS (Tinuvin® 791) and UV absorber (Hostavin® ARO 8), were prepared in a co‐rotating twin‐screw extruder. The effects of additives and their interactions were investigated by analyzing the mechanical properties, in tensile strength, scanning electron microscopy (SEM) and Differential Scanning Calorimetry (DSC). The results indicate that the incorporation of coir, in the presence of the compatibilizer, significantly increases tensile strength, but in the absence of the compatibilizer, the natural fibers act as stress concentrators, allowing a lower tensile strength to the sample. The joint presence of Tinuvin® and the compatibilizer has a negative effect on tensile strength and on the compatibility of the natural fiber with the matrix. UV absorber does not affect the compatibility of the PP/CF composites. POLYM. ENG. SCI., 57:1179–1185, 2017. © 2017 Society of Plastics Engineers
Discovery of gastric cancer specific biomarkers by the application of serum proteomics
Authors: Yoo Moon‐Won , Park Jisook , Han Hye‐Seung , Yun Yeo‐Min , Kang Jeong Won , Choi Do‐Young , Lee Joon won , Jung Jae Hun , Lee Kyung‐Yung , Kim Kwang Pyo
Published: January 2017

Current diagnostic markers for gastric cancer are not sufficiently specific or sensitive for use in clinical practice. The aims of this study are to compare the proteomes of serum samples from patients with gastric cancers and normal controls, and to develop useful tumor markers of gastric cancer by quantitative proteomic analysis. We identified a total of 388 proteins with a ≤1% FDR and with at least two unique peptides from the sera of each group. Among them, 215, 251, and 260 proteins were identified in serum samples of patients in an advanced cancer group, early cancer group, and normal control group, respectively. We selected differentially expressed proteins in cancer patients compared with those of normal controls via semiquantitative analyses comparing the spectral counts of identified proteins. These differentially expressed proteins were successfully verified using an MS‐based quantitative assay, multiple reactions monitoring analysis. Four proteins (vitronectin, clusterin isoform 1, thrombospondin 1, and tyrosine‐protein kinase SRMS) were shown to have significant changes between the cancer groups and the normal control group. These four serum proteins were able to discriminate gastric cancer patients from normal controls with sufficient specificity and selectivity.
Dynamic hierarchical models for monetary transmission
Authors: Parisi Laura
Published: January 2017

Monetary policies, either actual or perceived, cause changes in monetary interest rates. These changes impact the economy through financial institutions, which react to changes in the monetary policy with changes in their administered rates, on both deposits and lendings. In this paper we provide a dynamic modeling for describing how administered bank interest rates react in response to changes in money market rates, in a multicountry setting: in addition, by means of hierarchical equations, we take into account how such changes are affected by the macroeconomic fundamentals of each country. The paper applies the proposed models to interest rates on different loans (to corporates and families) in seven European economies, showing how the monetary policy and the specific situation of each country have differently impacted lendings across time.
Synthesis and Application of Magnetic Graphene Oxide Modified with 8‐Hydroxyquinoline for Extraction and Preconcentration of Trace Heavy Metal Ions
Authors: Dahaghin Zohreh , Mousavi Hassan Zavvar , Sajjadi S. Maryam
Published: January 2017

In the present paper for the first time, magnetic graphene oxide (GO‐Fe3O4) was modified with well‐known ligand 8‐hydroxyquinoline, as a new functional group, for simultaneous separation/pre‐concentration of Cd(II) and Pb(II) ions. The experiments and the optimization of variables affecting separation/preconcentration were designed, using the response surface methodology (BBD). In the optimized conditions, the limit of detection (LOD) was 0.09 ng mL–1 and 0.27 ng mL−1 for Cd(II) and Pb(II), respectively; furthermore, the pre‐concentration factor was obtained 130.43. The relative standard deviation (RSD) was 3.6 % and 3.9 % for Cd(II) and Pb(II) in the selected conditions, respectively. The procedure recommended was applied in order to determine Cd(II) and Pb(II) ions at trace levels in tomato, mushroom, lettuce, lipstick, and fish samples with satisfactory results.
Superiority of Activated Carbon versus MCM‐41 for the Immobilization of Molybdenum Dithiocarbamate Complex as Heterogeneous Epoxidation Catalyst
Authors: Masteri‐Farahani Majid , Modarres Maryam
Published: January 2017

Two heterogeneous catalysts were developed by covalent anchoring of molybdenum‐dithiocarbamate complex onto the mesoporous silica (MCM‐41) and activated carbon (AC). Characterization of the functionalized materials by various physicochemical techniques indicated that the molybdenum complex is grafted successfully on the surface of supports. Textural properties of the prepared catalysts proved that the surface properties of supports have been changed after grafting of molybdenum‐dithiocarbamate complex. These heterogeneous catalysts were utilized for the epoxidation of olefins with tert‐butyl hydroperoxide (TBHP) as oxidant, presenting high efficiency and facile recovery. These catalysts can be reused five times without apparent loss of their catalytic performance. Also, the effect of the nature of MCM‐41 and AC supports on the catalytic activity has been discussed based on their hydrophobic and hydrophilic character.
Synthesis, Structure and Catalytic Properties of Two Complexes: ((Butylthio)8porphyrazinato)cobalt(II), Co(PzS8) and ((Butyloxyl) (Butylthio)7porphyrazinato)cobalt(II), Co(PzOS7)
Authors: Zhou Peng , Ren Xiaomei , Liu Yang , Liu Yi , Zhang Bingguang , Yang Changjun , Deng Kejian
Published: January 2017

A novel porphyrazine, [2H] 2‐butyloxy‐3,7,8,12,13,17,18‐heptakis(butylthio) porphyrazine (H2PzOS7), was obtained with a yield 13 % when preparing [2H] 2,3,7,8,12,13,17,18‐octakis‐ (butylthio) porphyrazine (H2PzS8). The crystal structures of cobalt(II) complexes, CoPzOS7 and CoPzS8, were determined by single crystal X‐ray diffraction analysis. And the structural characterizations by 1H‐NMR, 1H‐1HCOSY, 13C‐NMR, UV‐Vis and MALDI‐TOF MS were combined for confirmation. Moreover, the cobalt complexes were employed as catalysts in the oxidation of benzyl alcohol with various oxidants including O2, H2O2 and t‐BuOOH. Superior conversion rate was obtained with H2O2 and t‐BuOOH at ambient condition. For assessing the capacity of O2 activation, the reaction was conducted under pressurized condition. Since the β‐pyrrole position was asymmetrically replaced by a butyloxy group, the reaction rate catalyzed by CoPzOS7 was over twice than by CoPzS8. The conversion rate of benzyl alcohol reached over 80 % within 6 h. Moreover, the aldehyde yield for oxidation of extended substituent benzyl alcohols catalyzed by CoPzOS7 was also 1–2 times higher than by CoPzS8 in same reaction time. Especially their oxidative selectivities were all 100 %! The cyclic voltammograms indicate that the potentials of CoIII/CoII are closely related to the activity of the catalyst.
A Green pH‐switchable Amino Acid Based Smart Wormlike Micellar System for Efficient and Controlled Drug Delivery
Authors: Lone Mohd Sajid , Bhat Parvaiz Ahmad , Shah Rais Ahmad , Chat Oyais Ahmad , Dar Aijaz Ahmad
Published: January 2017

A biocompatible and biodegradable amino‐acid based anionic surfactant system has been formulated which self assembles into wormlike micelles in presence of NaCl and displays excellent sol‐gel transition under pH stimulus. The surfactant synthesized was Sodiumtetradecanoyl Phenyl Alanine (STDPA). The micellar solution behaves as sol at /below pH 8.25 and transforms into gel at /above pH 8.65, exhibiting sol‐gel transition in a very narrow pH range. This pH triggered sol‐gel transition shows excellent reversibility upon recurrent changes in pH. Steady and dynamic rheological experiments reveal that the solution at/above pH 8.65 is viscoelastic due to the formation of wormlike micelles (WLMs) and was Newtonian at/below 8.25 due to the presence of spherical micelles. The microstructural evolution was further validated by Dynamic Light Scattering and Cryo TEM imaging. Further, the formulation was used to study the release of drug Ibuprofen (IBU) at these two pHs. IBU release from the material depends on pH of the release medium and occurs without any burst release at pH 8.65.
Silver‐Mediated C−S Cross‐Coupling of Di(pyrimidin‐2‐yl) Disulfides with Aliphatic Carboxylic Acids
Authors: Wang Wen‐Juan , Liu Xiao‐Jun , Wang Xi–Cun
Published: January 2017

A silver‐mediated decarboxylative cross‐coupling of aliphatic carboxylic acids to deliver C−S couplings products is reported. This reaction occurs smoothly under mild conditions and tolerates a various 1,2‐di(pyrimidin‐2‐yl)disulfides and aliphatic carboxylic acids bearing both electron‐donating and electron‐withdrawing groups. It provides an alternative approach for the synthesis of alkyl pyrimidinyl sulfides, which may be applied as the key intermediates in the synthesis of drug candidates.
A Green and Recyclable Copper and Ionic Liquid Catalytic System for the Construction of Poly‐heterocyclic Compounds via One‐pot Tandem Coupling Reaction
Authors: Naidu Shivaji , Reddy Sabbasani Rajasekhara
Published: January 2017

In this contribution, we report the environmentally benign synthesis of various N‐containing heterocyclic compounds from two simple starting materials, 2‐aminobenzoic acid and/ or 2‐aminobenzamide and 4‐pentynoic acid using copper as a catalyst in ionic liquid media. This synthetic methodology affords products with good to excellent yield with several advantages such as less toxicity of catalyst, green solvent media and easy isolation of products. Both the catalyst and ionic liquid were successfully reused and recycled up to five times without any significant loss of activity.
Designing Small Molecule Organic Solar Cells with High Open‐Circuit Voltage
Authors: Kudrjasova Julija , Van Landeghem Melissa , Vangerven Tim , Kesters Jurgen , Heintges Gaël H. L. , Cardinaletti Ilaria , Lenaerts Ruben , Penxten Huguette , Adriaensens Peter , Lutsen Laurence , Vanderzande Dirk , Manca Jean , Goovaerts Etienne , Maes Wouter
Published: January 2017

Three extended 2,5‐dithienylthiazolo[5,4‐d]thiazole‐based small molecule chromophores are prepared via a sustainable direct arylation approach and their physicochemical and opto‐electrical material characteristics are analyzed toward integration in solution‐processed bulk heterojunction organic photovoltaics. Efficient charge separation and high values of the charge transfer state energy are derived from sensitive ground and excited state absorption and photoluminescence measurements on blends of the thiazolo[5,4‐d]thiazole‐based electron donor components with the PC71BM fullerene acceptor. Upon implementation in organic solar cells, a maximum power conversion efficiency of 2.7% and particularly high open‐circuit voltages (0.93−0.98 V) are observed, which are correlated to the charge transfer state energies as derived from photoluminescence, Fourier transform photocurrent spectroscopy and combined electrochemical and photophysical data. Furthermore, several loss processes at the origin of the modest short‐circuit current densities and fill factors are elucidated.
Synthesis, Complexation and DFT Computational Studies of Bis(naphthyl)methane‐“Capped” Triazole‐Linked Calix[4]arenes as Fe3+ Fluorescent Chemosensors
Authors: Aljabri Mahmood D. , Rahman Shofiur , Georghiou Paris E.
Published: January 2017

Two new substituted‐bis(naphthyl)methane “capped” 1,2,3‐triazole‐linked calix[4]arene receptors have been synthesized and characterized. Their binding properties toward different biologically relevant metal ions were studied by fluorescence spectroscopy titrations and 1H NMR spectroscopy. The fluorescence spectral changes show that are sensitive and selective for Fe3+ ions and the binding modes have been confirmed based upon both the 1H NMR and DFT studies.
Bioactivity‐Guided Isolation, Antimicrobial and Cytotoxic Evaluation of Secondary Metabolites from Cladosporium tenuissimum Associated with Pinus wallichiana
Authors: Naseer Syed , Bhat Khursheed A. , Qadri Masroor , Riyaz‐Ul‐Hassan Syed , Malik Fayaz A. , Khuroo Mohammad A.
Published: January 2017

Cladosporium tenuissimum, an endophyte, was isolated from Pinus wallichiana growing in the Western Himalayas of Lolab Valley (Kashmir India) and analysed for its secondary metabolite composition. Column chromatography of the culture broth lead to the isolation of three bioactive molecules viz; (3S, 5S, 11S)‐trihydroxydodecanoic acid, scytalone and o‐hydroxyphenyl acetone. The stereochemistry of (3S, 5S, 11S)‐trihydroxydodecanoic acid was deduced from pandangolide. Pandangolide has been isolated from Cladosporium species and its stereochemistry is known. The isolated constituents were evaluated for cytotoxic and antimicrobial potential against MCF‐7, T47D, MDA‐MB‐231 cell lines and ATCC 29213, ATCC 25922, IIIM 25, MTCC 4748 strains. (3S, 5S, 11S)‐trihydroxydodecanoic acid exhibited significant cytotoxic activity against the human breast cancer cell line (MCF‐7) with an IC50 of 15 μg/ml. o‐Hydroxyphenyl acetone displayed prominent antimicrobial activity against Bacillus cereus IIIM 25 (Gram positive) and Escherichia coli ATCC 25922 (Gram negative) with IC50 of 23.3μg/ml and 43.7μg/ml respectively. o‐Hydroxyphenyl acetone is being reported for the first time from any natural source while as (3S, 5S, 11S)‐trihydroxydodecanoic acid and scytalone for the first time from C. tenuissimum.
A Fast and Additive Free C–C Homo/Cross‐Coupling Reaction in Reverse Micelle: An Understanding of Role of Surfactant, Water Content and Base on the Product Yield and Reaction Site
Authors: Kar Barnali , Bardhan Soumik , Ghosh Prasanjit , Ganguly Bhaskar , Kundu Kaushik , Sarkar Sonali , Paul Bidyut Kumar , Das Sajal
Published: January 2017

A fresh modus operandi was designed for additive and ligand free transition metal‐catalyzed C−C homo/cross‐coupling reactions of arylboronic acid in reverse micellar (RMs) templates. Three RMs based on different charge types of polar head groups and length of hydrophobic moieties of surfactants [e. g., anionic (AOT), cationic (DDAB), and non‐ionic (TX 100)] in cyclohexane were chosen herein. The reaction proceeded rapidly in these RMs and completed within 10 minutes at ambient condition. Performance of reaction in terms of yield of the desired product in RMs, was correlated with various physicochemical parameters of these systems as obtained from conductance, DLS and FTIR techniques. The results revealed that AOT is best suited for further studies. The progress of the reaction with time was monitored in AOT RMs as supplementary study by using above mentioned methods. It was emphasized that types of base and catalyst, water content influenced the product yield and plausible reaction location. Finally, the development of a series of symmetrical and unsymmetrical biarylviaabove reaction in AOT RM was explored successfully.
Synthesis of Chromeno[4,3‐b]pyrrol‐4(1H)‐ones, from β‐Nitroalkenes and 4‐Phenylaminocoumarins, under Solvent–free Conditions
Authors: Padilha Gustavo , Iglesias Bernardo A. , Back Davi F. , Kaufman Teodoro S. , Silveira Claudio C.
Published: January 2017

A new approach toward chromeno[4,3‐b]pyrrol‐4(1H)‐ones, by annulation of 4‐phenylaminocoumarins with β‐nitroalkenes, is reported and its conditions were optimized. The transformations under the fine‐tuned conditions took place under promotion by TsOH.H2O, in the absence of solvent. The scope and limitations of the process were explored, by systematic modification of two diversification points. A reaction mechanism, triggered by a Michael addition of the nitrogen moiety of the 4‐phenylaminocoumarins to the β‐nitroalkene, was also proposed. Further functionalization of a selected tricycle was performed; the photophysical (UV and fluorescence spectra; 1O2 generation) and electrochemical (cyclic voltammetry) properties of some heterocycles were studied.