bluuebunny/crossref_metadata_2025_split huggingface dataset:
Soil Greenhouse Gas Fluxes, Environmental Controls, and the Partitioning of N2O Sources in UK Natural and Seminatural Land Use Types
Authors: Sgouridis Fotis , Ullah Sami 
Published: September 2017

AbstractNatural and seminatural terrestrial ecosystems (unmanaged peatlands and forests and extensive and intensive grasslands) have been under‐represented in the UK greenhouse gas (GHG) inventory. Mechanistic studies of GHG fluxes and their controls can improve the prediction of the currently uncertain GHG annual emission estimates. The source apportionment of N2O emissions can further inform management plans for GHG mitigation. We have measured in situ GHG fluxes monthly in two replicated UK catchments and evaluated their environmental controlling factors. An adapted 15N‐gas flux method with low addition of 15N tracer (0.03–0.5 kg 15N ha−1) was used to quantify the relative contribution of denitrification to net N2O production. Total N2O fluxes were 40 times higher in the intensive grasslands than in the peatlands (range: −1.32 to 312.3 μg N m−2 h−1). The contribution of denitrification to net N2O emission varied across the land use types and ranged from 9 to 60%. Soil moisture was the key parameter regulating the partitioning of N2O sources (r2 = 0.46). Total N2O fluxes were explained by a simple model (r2 = 0.83) including parameters such as total dissolved nitrogen, organic carbon, and water content. A parsimonious model with the soil moisture content as a single scalar parameter explained 84% of methane flux variability across land uses. The assumption that 1% of the atmospherically deposited N on natural ecosystems is emitted as N2O could be overestimated or underestimated (0.3–1.6%). The use of land use‐specific N2O emission factors and further information on N2O source partitioning should help constrain this uncertainty.
Biomechanical Regulation of Mesenchymal Stem Cells for Cardiovascular Tissue Engineering
Authors: Henderson Kayla , Sligar Andrew D. , Le Victoria P. , Lee Jason , Baker Aaron B. 
Published: September 2017

AbstractMesenchymal stem cells (MSCs) are an appealing potential therapy for vascular diseases; however, many challenges remain in their clinical translation. While the use of biochemical, pharmacological, and substrate‐mediated treatments to condition MSCs has been subjected to intense investigation, there has been far less exploration of using these treatments in combination with applied mechanical force for conditioning MSCs toward vascular phenotypes. This review summarizes the current understanding of the use of applied mechanical forces to differentiate MSCs into vascular cells and enhance their therapeutic potential for cardiovascular disease. First recent work on the use of material‐based mechanical cues for differentiation of MSCs into vascular and cardiovascular phenotypes is examined. Then a summary of the studies using mechanical stretch or shear stress in combination with biochemical treatments to enhance vascular phenotypes in MSCs is presented.
A Reloadable Self‐Healing Hydrogel Enabling Diffusive Transport of C‐Dots Across Gel–Gel Interface for Scavenging Reactive Oxygen Species
Authors: Chen Jing , Li Shuya , Zhang Ye , Wang Wei , Zhang Xiang , Zhao Yangyang , Wang Yucai , Bi Hong 
Published: September 2017

AbstractWhile reloadable drug delivery platforms are highly prized for the treatment of a broad spectrum of diseases, the gel–gel interface between hydrogels hinders the intergel diffusive transport of drugs and thus limits the application of hydrogels as reloadable depots. Here, this study reports the circumvention of this barrier by employing a self‐healing hydrogel prepared from N‐carboxyethyl chitosan and sodium alginate dialdehyde, which are cross‐linked via a reversible Schiff base linkage. The injectable and bioadhesive hydrogel shows a rapid gelation time of 47 s. The dynamic self‐healing process enables the efficient diffusive transport of carbon quantum dots (C‐dots) into an adjacent hydrogel, and thus, the C‐dots can be used to scavenge reactive oxygen species from a remote inflammation site. Specifically, the diffusive transport of the C‐dots in the self‐healing hydrogel after three sequential reloading steps is sevenfold greater than that in the non‐self‐healing counterpart. In vivo, hematoxylin and eosin staining of the murine skin at the injection site shows no apparent symptoms of inflammation in the group treated with the reloadable self‐healing hydrogel. The current strategy represents a promising and straightforward route for the design of a reloadable drug delivery system for future use in clinical application.
Membrane Fusion Mediated Intracellular Delivery of Lipid Bilayer Coated Mesoporous Silica Nanoparticles
Authors: Yang Jian , Tu Jing , Lamers Gerda E. M. , Olsthoorn René C. L. , Kros Alexander 
Published: September 2017

AbstractProtein delivery into the cytosol of cells is a challenging topic in the field of nanomedicine, because cellular uptake and endosomal escape are typically inefficient, hampering clinical applications. In this contribution cuboidal mesoporous silica nanoparticles (MSNs) containing disk‐shaped cavities with a large pore diameter (10 nm) are studied as a protein delivery vehicle using cytochrome‐c (cytC) as a model membrane‐impermeable protein. To ensure colloidal stability, the MSNs are coated with a fusogenic lipid bilayer (LB) and cellular uptake is induced by a complementary pair of coiled‐coil (CC) lipopeptides. Coiled‐coil induced membrane fusion leads to the efficient cytosolic delivery of cytC and triggers apoptosis of cells. Delivery of these LB coated MSNs in the presence of various endocytosis inhibitors strongly suggests that membrane fusion is the dominant mechanism of cellular uptake. This method is potentially a universal way for the efficient delivery of any type of inorganic nanoparticle or protein into cells mediated by CC induced membrane fusion.
Highly Efficient Rubrene–Graphene Charge‐Transfer Interfaces as Phototransistors in the Visible Regime
Authors: Jones Gareth F. , Pinto Rui M. , De Sanctis Adolfo , Nagareddy V. Karthik , Wright C. David , Alves Helena , Craciun Monica F. , Russo Saverio 
Published: September 2017

AbstractAtomically thin materials such as graphene are uniquely responsive to charge transfer from adjacent materials, making them ideal charge‐transport layers in phototransistor devices. Effective implementation of organic semiconductors as a photoactive layer would open up a multitude of applications in biomimetic circuitry and ultra‐broadband imaging but polycrystalline and amorphous thin films have shown inferior performance compared to inorganic semiconductors. Here, the long‐range order in rubrene single crystals is utilized to engineer organic‐semiconductor–graphene phototransistors surpassing previously reported photogating efficiencies by one order of magnitude. Phototransistors based upon these interfaces are spectrally selective to visible wavelengths and, through photoconductive gain mechanisms, achieve responsivity as large as 107 A W−1 and a detectivity of 9 × 1011 Jones at room temperature. These findings point toward implementing low‐cost, flexible materials for amplified imaging at ultralow light levels.
Harnessing Photochemical Shrinkage in Direct Laser Writing for Shape Morphing of Polymer Sheets
Authors: Bauhofer Anton A. , Krödel Sebastian , Rys Jan , Bilal Osama R. , Constantinescu Andrei , Daraio Chiara 
Published: September 2017

AbstractStructures that change their shape in response to external stimuli unfold possibilities for more efficient and versatile production of 3D objects. Direct laser writing (DLW) is a technique based on two‐photon polymerization that allows the fabrication of microstructures with complex 3D geometries. Here, it is shown that polymerization shrinkage in DLW can be utilized to create structures with locally controllable residual stresses that enable programmable, self‐bending behavior. To demonstrate this concept, planar and 3D‐structured sheets are preprogrammed to evolve into bio‐inspired shapes (lotus flowers and shark skins). The fundamental mechanisms that control the self‐bending behavior are identified and tested with microscale experiments. Based on the findings, an analytical model is introduced to quantitatively predict bending curvatures of the fabricated sheets. The proposed method enables simple fabrication of objects with complex geometries and precisely controllable shape morphing potential, while drastically reducing the required fabrication times for producing 3D, hierarchical microstructures over large areas in the order of square centimeters.
Chemo‐ and Diastereoselective Construction of Indenopyrazolines via a Cascade aza‐Michael/Aldol Annulation of Huisgen Zwitterions with 2‐Arylideneindane‐1,3‐diones
Authors: Li Yuming , Zhang Haikun , Wei Rong , Miao Zhiwei 
Published: September 2017

AbstractA cascade aza‐Michael/Aldol annulation of 2‐arylideneindane‐1,3‐diones with in situ generated Huisgen zwitterions has been developed. This reaction afforded the desired products in moderate to good yields (up to 87%) with excellent chemo‐ and diastereoselectivity (up to 20:1). This strategy allows facile diastereoselective preparation of biologically important indenopyrazoline derivatives containing two contiguous chiral centers including a quaternary stereogenic center.magnified image
Hematological Effects of Gold Nanorods on Erythrocytes: Hemolysis and Hemoglobin Conformational and Functional Changes
Authors: Zhao Xingchen , Lu Dawei , Liu Qian S. , Li Yiling , Feng Rui , Hao Fang , Qu Guangbo , Zhou Qunfang , Jiang Guibin 
Published: September 2017

AbstractGold nanorods (GNRs) are a unique class of metal nanostructures that have attractive potentials in biomedical applications, and the concern on their biological safety is concomitantly increasing. Hemocompatibility is extremely important as their contact with blood circulation is unavoidable during in vivo delivery. Herein, two kinds of GNRs coated with hexadecyltrimethylammonium bromide (C‐GNRs) or poly(sodium‐p‐styrenesulfonate) are used to test their potential toxicological effects in blood. C‐GNRs with positive surface charges efficiently induce hemolysis when encountering erythrocytes. Cellular internalization of C‐GNRs is found, and they subsequently bind with hemoglobin, forming bioconjugates. The interaction between hemoglobin and C‐GNR (stoichiometry 32.7:1) is regulated by electrostatic forces. Chromophores like tryptophan (Trp) are found to interact with C‐GNRs, causing enhancement in fluorescence intensity. The conformation of protein is partially altered, evidenced by decrease in α‐helical, increase in β‐sheet and random coil of hemoglobin. Although C‐GNRs do not essentially decrease oxygen binding capacity of hemoglobin, they hamper oxygen release from the protein. Heme, the oxygen binding unit, releases from hemoglobin upon C‐GNR treatment, which could contribute to C‐GNR‐induced hemolysis. This study demonstrates the hematological effects of GNRs, revealing their potential risk in biomedical applications.
Achieving High Open‐Circuit Voltages up to 1.57 V in Hole‐Transport‐Material‐Free MAPbBr3 Solar Cells with Carbon Electrodes
Authors: Liang Yongqi , Wang Yajuan , Mu Cheng , Wang Sen , Wang Xinnan , Xu Dongsheng , Sun Licheng 
Published: September 2017

AbstractAn open‐circuit voltage (Voc) of 1.57 V under simulated AM1.5 sunlight in planar MAPbBr3 solar cells with carbon (graphite) electrodes is obtained. The hole‐transport‐material‐free MAPbBr3 solar cells with the normal architecture (FTO/TiO2/MAPbBr3/carbon) show little hysteresis during current–voltage sweep under simulated AM1.5 sunlight. A solar‐to‐electricity power conversion efficiency of 8.70% is achieved with the champion device. Accordingly, it is proposed that the carbon electrodes are effective to extract photogenerated holes in MAPbBr3 solar cells, and the industry‐applicable carbon electrodes will not limit the performance of bromide‐based perovskite solar cells. Based on the analysis of the band alignment, it is found that the voltage (energy) loss across the interface between MAPbBr3 and carbon is very small compared to the offset between the valence band maximum of MAPbBr3 and the work function of graphite. This finding implies either Fermi level pinning or highly doped region inside MAPbBr3 layer exists. The band‐edge electroluminescence spectra of MAPbBr3 from the solar cells further support no back‐transfer pathways of electrons across the MAPbBr3/TiO2 interface.
Umgehung des Gas‐flüssig‐Stofftransports von Sauerstoff durch Kopplung der photosynthetischen Wasseroxidation an eine biokatalytische Oxyfunktionalisierung
Authors: Hoschek Anna , Bühler Bruno , Schmid Andreas 
Published: September 2017

AbstractDer Gas‐flüssig‐Stofftransport gasförmiger Reaktanten limitiert die Raum‐Zeit‐Ausbeute O2‐abhängiger (bio)katalytischer Reaktionen in wässrigen Lösungen. In dieser Studie wurde die oxygene Photosynthese für den homogenen Sauerstoffeintrag durch In‐situ‐Erzeugung von O2 in der Flüssigphase genutzt, um diese Limitierung zu umgehen. Hierfür produziert das phototrophe Cyanobakterium Synechocystis sp. PCC6803 als Ganzzellbiokatalysator heterolog die Alkanmonooxygenase AlkBGT aus Pseudomonas putida GPo1. Die chemo‐ und regioselektive Hydroxylierung von Pelargonsäuremethylester zu ω‐Hydroxypelargonsäuremethylester kann so bei Belichtung, jedoch ohne externe Zugabe von molekularem Sauerstoff katalysiert werden. Der Sauerstoff stammt aus der photosynthetischen Wasseroxidation. Die Photosynthese liefert ebenfalls die nötigen Reduktionsäquivalente zur Regeneration von Fe2+ in AlkB für den Sauerstofftransfer zur terminalen Methylgruppe. Die In‐situ‐Kopplung der oxygenen Photosynthese an O2‐übertragende Enzyme ermöglicht nun das Design schneller Oxyfunktionalisierungsreaktionen.
An αv‐RGD Integrin Inhibitor Toolbox: Drug Discovery Insight, Challenges and Opportunities
Authors: Hatley Richard J. D. , Macdonald Simon J. F. , Slack Robert J. , Le Joelle , Ludbrook Steven B. , Lukey Pauline T. 
Published: September 2017

AbstractThere is a requirement for efficacious and safe medicines to treat diseases with high unmet need. The resurgence in αv‐RGD integrin inhibitor drug discovery is poised to contribute to this requirement. However, drug discovery in the αv integrin space is notoriously difficult due to the receptors being structurally very similar as well as the polar zwitterionic nature of the pharmacophore. This Review aims to guide drug discovery research in this field through an αv inhibitor toolbox, consisting of small molecules and antibodies. Small‐molecule αv tool compounds with extended profiles in αvβ1, 3, 5, 6 and 8 cell adhesion assays, with key physicochemical properties, have been collated to assist in the selection of the right tool for the right experiment. This should also facilitate an understanding of partial selectivity profiles of compounds generated in different assays across research institutions. Prospects for further αv integrin research and the critical importance of target validation are discussed, where increased knowledge of the selectivity for individual RGD αv integrins is key. Insights into the design of small‐molecule RGD chemotypes for topical or oral administration are provided and clinical findings on advanced molecules are examined.
A novel and highly efficient polyaniline‐functionalized multiwall carbon nanotube‐supported cu(I) complex for Sonogashira coupling reactions of aryl halides with phenylacetylene
Authors: Hajipour Abdol R. , Jajarmi Saeideh 
Published: September 2017

A polyaniline‐functionalized multiwall carbon nanotube‐supported Cu(I) complex was developed as an efficient catalyst for the Sonogashira reactions of aryl halides with phenylacetylene in the presence of potassium hydroxide in dimethylformamide at 135 °C under nitrogen atmosphere. The corresponding products were generated in good to excellent yields using this catalytic system. Moreover, the multiwall carbon nanotube‐supported Cu(I) catalyst was simply recycled and reused for six consecutive runs.
Phthalhydrazide nanoparticles as new highly reusable organic photocatalyst in the photodegradation of organic and inorganic contaminants
Authors: Mohammadzadeh Kakhki Roya , Tayebee Reza , Hedayat Sara 
Published: September 2017

Phthalhydrazide nanoparticles are introduced as a new, efficient, stable and reusable organic photocatalyst for the photodegradation of a range of azo dyes, including methyl orange, methyl red, congo red and yellow titan, 4‐nitrophenol and permanganate as important organic and inorganic contaminants. Various experimental parameters including pH, photocatalyst dose, dye concentration and illumination time were investigated for methyl orange as a model substrate. The results revealed high degradation efficacy, up to 93.6%, for methyl orange in 20 min. Moreover, a preliminary kinetic study along with a proposed photodegradation mechanism is included in this study. Mechanistic investigations showed that phthalhydrazide behaved as a photoreduction catalyst. With the addition of Cl− ion, as a hole scavenger, photodegradation efficacy for methyl orange was improved. Results showed that phthalhydrazide nanoparticles behaved better than commercial bulk phthalhydrazide and both performed as successful photocatalysts for photoreduction of the mentioned organic and inorganic compounds.
Application of artificial neural network for comparison and modeling of the ultrasonic and stirrer assisted removal of anionic dye using activated carbon supported with nanostructure material
Authors: Ghaedi Abdol Mohammad , Karami Parisa , Ghaedi Mehrorang , Vafaei Azam , Alipanahpour Dil Ebrahim , Mehrabi Fatemeh 
Published: September 2017

In this study, a green approach has been described for the synthesis of copper sulfide nanoparticles loaded on activated carbon (CuS‐NP‐AC) and usability of it for the removal of sunset yellow (SY) dye by ultrasound‐assisted and stirrer has been compared. In addition, the artificial neural network (ANN) model has been employed for a forecasting removal percentage of SY dye using the results obtained. This material was characterized using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The impact of variables, including initial dye concentration (mg/L), pH, adsorbent dosage (g), sonication time (min) and temperature (°C) on SY removal was studied. Fitting the experimental equilibrium data of different isotherm models such as Langmuir, Freundlich, Temkin and Dubinin–Radushkevich models display the suitability and applicability of the Langmuir model. Analysis of experimental adsorption data of different kinetic models including pseudo‐first and second order, Elovich and intraparticle diffusion models indicate the applicability of the second‐order equation model. The adsorbent (0.005 g) is applicable for successful removal of SY dye (> 98%) in short time (9 min) under ultrasound condition. A three layer ANN models with 8 and 6 neurons at hidden layer was selected as optimal models using stirrer and ultrasonic, respectively. These models displayed a good agreement between forecasted data and experimental data with the determination coefficient (R2) of 0.9948 and 0.9907 and mean squared error (MSE) of 0.0001 and 0.0002 for training set using stirrer and ultrasonic, respectively.
Retracted: Catalytic activity of Fe(II) and Cu(II) PNP pincer complexes for Suzuki coupling reaction
Authors: Kumar Lolakshi Mahesh , Ansari Rasheeda M. , Bhat Badekai Ramachandra 
Published: September 2017

Iron and copper PNP pincer complexes of the type [Fe(L)SO4] and [Cu(L)OCOCH3] are reported and represented as C‐1 and C‐2 catalyst. Both the complexes were synthesized using bis(diphenylphosphino)pyridine‐2,6‐diamine [L], and salts of ‘Fe’ and ‘Cu’ by direct coordination method. The as synthesized complexes were characterized using FTIR, UV–Vis, mass analysis and TGA. The effect of reaction time, catalyst load, solvent and base on the reaction between phenylboronic acid and para substituted bromobenzenes in the presence of the catalysts were investigated for evaluating the catalytic efficiency of the complexes. The results obtained highlight the enhanced C‐C coupling reactions with the use of 0.4 mol% of the catalyst C‐1 in 14 h and 0.6 mol% of C‐2 in 16 h respectively with Cs2CO3 base and ACN as solvent media. Of the two complexes reported, C‐1 with iron as catalytically active metal is more stable and active towards coupling which is reflected in its better coupling yields in lesser reaction time compared to copper bearing C‐2 complex.
Catalytic reactivity of new Ni(II), Cu(II) and Sn(II) complexes for decolorization of indigo carmine in aqueous solution, high efficiency of copper complex
Authors: Nassar Amr Mohammad 
Published: September 2017

A new Ni(II), Cu(II) and Sn(II) Schiff base complexes were synthesized in this work. The characterization of the new complexes is carried out by elemental analysis, FT‐IR, UV–Visible, 1H NMR and 13C NMR spectroscopy, conductance analysis, magnetic measurements and thermal gravimetric analysis. It was found that the ligand behaves as a dibasic bidentate which coordinated to the metal center through two deprotonated hydroxyl groups to form tetrahedral complex with Ni(II) and octahedral complex with Cu(II). The ligand acts as neutral bidentate through azomethine nitrogen and thiazol sulfur to form octahedral complex with Sn(II). The synthesized complexes are evaluated as catalysts for oxidative degradation of indigo carmine dye using H2O2 as oxidant and the efficiency of the catalysts is determined. The copper complex shows the best catalytic action with efficiency 92.17% after 25 min.
Curing of polyfurfuryl alcohol resin catalyzed by a homologous series of dicarboxylic acid catalysts. II. Swelling behavior and thermal properties
Authors: Marefat Seyedlar Roghayyeh , Imani Mohammad , Mirabedini S. Mojtaba 
Published: September 2017

ABSTRACTPolyfurfuryl alcohol (PFA), as a bio‐based resin made from lignocellulosic materials, was crosslinked using a homologous series of dicarboxylic acid catalysts consisting of oxalic, succinic, and adipic acids, which are different in their dissociation constants. Swelling behavior, thermal stability, and non‐oxidative char residue of the resulting networks were characterized as a function of the acids strength and their concentration. Swelling of the networks were investigated at room temperature in eight solvents differing in molecular size and solubility parameter. Using acetonitrile as a solvent, the swelling mechanism was explored by applying kinetic models to the swelling data. Dynamic swelling studies during 16–30 days supported non‐Fickian and anomalous diffusion mechanism in highly crosslinked samples supporting PFA chain rigidity and high crosslinking density of the networks. Polymer–solvent interaction parameter, molecular weight between crosslinks and crosslinking densities were also determined. According to the results, the extent of PFA crosslinking and non‐Fickian behavior of the swelling solvent diffusion through the networks are strongly dependent on the concentration and dissociation characteristics of the catalysts used. Thermal stability studies showed no significant differences between the compositions, up to 900 °C. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45770.