bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrochemistry as an Attractive and Effective Tool for the Synthesis and Immobilization of Porphyrins on an Electrode Surface
Authors: Hebié Seydou , Dimé Abdou K. D. , Devillers Charles H. , Lucas Dominique 
Published: April 2015

AbstractMagnesium(II) 10‐phenyl‐5,15‐p‐ditolylporphyrin is easily and cleanly transformed by electrolysis. A nitro group is first introduced at the free meso position by anodic substitution. Hydrogenation into the amine is then carried out electrocatalytically under ambient conditions with water as a hydrogen supplier. The synthesized porphyrin under the nickel(II) form can be covalently grafted onto a platinum electrode by electrochemical reduction of the diazonium cation, generated in situ by a reaction of the nickel(II) aminoporphyrin with sodium nitrite and trifluoroacetic acid. The electrosynthesized thin film gives an electrochemical response typical of a porphyrin material. Films grown under our conditions have a maximum surface coverage of approximately 5×10−10 mol cm−2. The modified electrode exhibits a reproducible electrochemical behavior and a good level of stability over potential cycling and exposition to air.
Protein Flexibility in Drug Discovery: From Theory to Computation
Authors: Buonfiglio Rosa , Recanatini Maurizio , Masetti Matteo 
Published: April 2015

AbstractNowadays it is widely accepted that the mechanisms of biomolecular recognition are strongly coupled to the intrinsic dynamic of proteins. In past years, this evidence has prompted the development of theoretical models of recognition able to describe ligand binding assisted by protein conformational changes. On a different perspective, the need to take into account protein flexibility in structure‐based drug discovery has stimulated the development of several and extremely diversified computational methods. Herein, on the basis of a parallel between the major recognition models and the simulation strategies used to account for protein flexibility in ligand binding, we sort out and describe the most innovative and promising implementations for structure‐based drug discovery.
Gas‐Phase Affinity Scales for Typical Ionic Liquid Moieties Determined by using Cooks’ Kinetic Method
Authors: Vitorino Joana , Leal João Paulo , Minas da Piedade Manuel E. 
Published: April 2015

AbstractGas‐phase affinity studies based on cations and anions commonly present in ionic liquid structures, give quantitative information about the magnitude of the interactions holding the two species together when ILs are formed. They also provide clues on how these interactions depend on the nature of the cationic and anionic moieties. In the present work, mass spectrometric experiments, performed using electrospray ionization quadrupole ion‐trap and Fourier transform ion cyclotron resonance mass spectrometry, were used to obtain two affinity scales by Cooks’ kinetic method: one scale for the various cations for the bis(trifluoromethylsulfonyl)imide anion, [NTf2]−, and another for the different anions for the 1‐butyl‐3‐methylimidazolium cation, [C4mim]+. The obtained results are compared with previously reported data and discussed in terms of the structural characteristics of the different cationic and anionic species.
Topotecan‐induced ABCG2 expression in MCF‐7 cells is associated with decreased CD24 and EpCAM expression and a loss of tumorigenicity
Authors: Huber Stefan , Wege Anja K. , Bernhardt Günther , Buschauer Armin , Brockhoff Gero 
Published: April 2015

AbstractHuman breast cancer shows a considerable heterogeneity regarding the expression of CD24, CD44, EpCAM, and HER2. These markers are involved in cell adhesion, migration, and proliferation, and thus affect metastasis and, in turn, patient's outcome. The ATP‐driven efflux pump (ABC transporter) breast cancer resistance protein (BCRP, ABCG2) is known to confer resistance to a wide variety of structurally unrelated cytostatics and defines subpopulations with enhanced tumor‐initiating capacity. The expression of ABCG2 can be induced by treatment with different cytostatic drugs. Concurrent effects of such treatments on the expression of the aforementioned marker proteins and cellular properties related to cancer‐initiating cells have not been examined thoroughly. Here, we investigated the effect of the ABCG2 substrate topotecan on the MCF‐7 breast cancer cell line and analyzed CD24, CD44, EpCAM, and HER2 expression by flow cytometry. Moreover, we examined the impact of topotecan treatment on the sphere‐forming ability in vitro and the tumorigenicity in immunodeficient NMRI‐nu/nu and NSG mice. We found an elevated ABCG2 expression in MCF‐7 cells in the presence of 500 nM topotecan. Compared with untreated MCF‐7 cells, the application of topotecan induced a subpopulation with decreased CD24/EpCAM expression, whereas CD44 expression remained largely unchanged. Topotecan‐treated cells showed an impaired mammosphere formation capacity in vitro and reduced tumorigenicity in immunodeficient mice. The data indicate that ABCG2 induction is not necessarily linked to increased tumorigenicity and suggest a major role of CD24 and EpCAM for the preservation of self‐renewal capacity in MCF‐7 cells and tumor outgrowth in vivo. © 2015 International Society for Advancement of Cytometry
Identification of parameters for comparing the trial data and the simulation model, using as the example brickwork exposed to fire / Parameteridentifikation zum Abgleich von Versuchsdaten und Simulationsmodell am Beispiel brandbeanspruchten Mauerwerks
Authors: Schlegel Roger 
Published: April 2015

AbstractTrials and simulations provide important aids in the development of products for constructing brickwork. The balance between measurement and simulation is one of the classic duties for model validation. If the difference between the measurement and the recalculation is excessive, an approximation task for minimizing the differences can be formulated. Optimization tasks for calibration between measurement and simulation are often deemed to be an identification problem. In the past this task was generally processed through iterative adaptation of individual characteristics. With the availability of parameter optimization programs, the iterative manual alignment can be automated and even more complex tasks can be dealt with. The necessity of such automated identification procedures becomes even more important due to the speed of innovation in current product development processes. Within virtual prototyping, virtual testing is the key towards a reduction in hardware tests. Only when reference experiments achieve a comparison of major results between measurement and simulation, can it be presumed that all the relevant phenomena for the actual test result are included in the virtual model and thus predictable models are available for virtual testing. Using brickwork exposed to fire as the example, with the aid of modern mathematical procedures, the article shows that parameter identification can be carried out in a systematic, efficient and target orientated manner.
Field report on application of the dimensioning procedure according to E DIN 4109‐2 / Erfahrungsbericht zur Anwendung des Bemessungsverfahrens nach E DIN 4109‐2
Authors: Naumann Kai 
Published: April 2015

AbstractFor several years, the sound insulation ratings for multi‐storey buildings have been in transition and are being brought into line with the European calculation method according to EN 12354:2000. The drafts of DIN 4109 have been available since November 2013. The forecasting procedure for the expected airborne sound insulation in solid buildings will change considerably by comparison to the regulations in Supplement 1 to DIN 4109:1989.In recent years, the building acoustics testing unit of Xella Technologie‐ und Forschungsgesellschaft mbH has carried out numerous quality tests to determine the acoustic insulation of apartment partitioning walls and apartment partitioning floors in apartment buildings. The exterior walls of the buildings reviewed consist exclusively of plastered, autoclaved aerated concrete block walls. The interior walls were made primarily of autoclaved aerated concrete or limestone blocks. In a few cases, dry constructed or reinforced concrete inner walls were present. A comparison is presented between the test results of these quality tests and the design values of the assessed sound reduction index R’w according to E DIN 4109‐2:2013. During these tests, a discussion took place on the uncertainty that must be incorporated in the calculation so as to achieve an adequately high level of planning assurance.
Strategies of zooplanktivory shape the dynamics and diversity of littoral plankton communities: a mesocosm approach
Authors: Helenius Laura K. , Aymà Padrós Anna , Leskinen Elina , Lehtonen Hannu , Nurminen Leena 
Published: April 2015

AbstractPlanktivorous fish can exert strong top‐down control on zooplankton communities. By incorporating different feeding strategies, from selective particulate feeding to cruising filter feeding, fish species target distinct prey. In this study, we investigated the effects of two species with different feeding strategies, the three‐spined stickleback (Gasterosteus aculeatus (L.)) and roach (Rutilus rutilus (L.)), on a low‐diversity brackish water zooplankton community using a 16‐day mesocosm experiment. The experiment was conducted on a small‐bodied spring zooplankton community in high‐nutrient conditions, as well as a large‐bodied summer community in low‐nutrient conditions. Effects were highly dependent on the initial zooplankton community structure and hence seasonal variation. In a small‐bodied community with high predation pressure and no dispersal or migration, the selective particulate‐feeding stickleback depleted the zooplankton community and decreased its diversity more radically than the cruising filter‐feeding roach. Cladocerans rather than copepods were efficiently removed by predation, and their removal caused altered patterns in rotifer abundance. In a large‐bodied summer community with initial high taxonomic and functional diversity, predation pressure was lower and resource availability was high for omnivorous crustaceans preying on other zooplankton. In this community, predation maintained diversity, regardless of predator species. During both experimental periods, predation influenced the competitive relationship between the dominant calanoid copepods, and altered species composition and size structure of the zooplankton community. Changes also occurred to an extent at the level of nontarget prey, such as microzooplankton and rotifers, emphasizing the importance of subtle predation effects. We discuss our results in the context of the adaptive foraging mechanism and relate them to the natural littoral community.
Investigations Concerning [Cu4OX6L4] Cluster Formation of Copper(II) Chloride with Amine Ligands Related to Benzylamine
Authors: Becker Sabine , Behrens Ulrich , Schindler Siegfried 
Published: April 2015

AbstractThe μ4‐oxido motif is well known in copper clusters and often forms spontaneously and unexpectedly; however, little is known about the reaction conditions that generate μ4‐oxido clusters. This is surprising because these μ4‐oxido copper clusters seem to play an important role in catalysis. Herein, a systematic investigation of μ4‐oxido cluster formation is reported. The influence of several factors on cluster formation was studied, namely, the ligand environment, the central chalcogenide atom, and the bridging halido ligands. In this context, the crystal structures of the copper clusters and complexes [Cu4OCl6L24][CuL22Cl2] (L2 = phenethylamine), [CuL32Cl2] (L3 = N‐methylbenzylamine), [Cu4OCl6L44] (L4 = N,N‐dimethylbenzylamine), [CuL54Cl2] (L5 = cyclohexylamine), and [Cu4OCl6L64]·1.5[CuL62Cl2] (L6 = cyclohexanemethylamine) as well as that of HL4Cl are reported. Furthermore, the acetonitrile complexes [Cu(CH3CN)4][CuBr4], [Cu(CH3CN)Br], and [Cu(CH3CN)Br2] were obtained and characterized within attempts to prepare a μ4‐sulfido unit. The reaction conditions that generate μ4‐oxido cluster units are discussed in more detail.
One‐Pot Synthesis of 2‐Amino‐1,3‐selenazole via an Intermediary Amidinoselenourea
Authors: Ranjan Alok , Yerande Ragini , Jadhav Mahantesh , Yerande Swapnil G. , Dethe Dattatraya H. 
Published: April 2015

AbstractHerein we describe a sequential one‐pot multicomponent reaction for the synthesis of 2‐amino‐1,3‐selenazole. Amidinoselenourea synthesized from isoselenocyanate and N,N‐diethyl‐amidine reacted with various halomethylene compounds to furnish 2‐amino‐1,3‐selenazole derivatives in 65–89 % yields. The molecular structure of the trisubstituted selenazole formed was unambiguously established by X‐ray crystallography.
Writing From Behind the Fence
Authors: Gavigan Karen , Albright Kendra 
Published: April 2015

AbstractGraphic novels are an increasingly popular format that educators can use as a tool to teach reading and writing skills across the K–12 curriculum. This article describes a project in which incarcerated youths collaborated with a graphic illustrator to create a graphic novel about teens dealing with issues related toHIV/AIDS. The graphic novel is currently being used as anHIV/AIDSeducation and prevention tool for teens. The article examines the impact that creating a graphic novel had on the literacy lives of the young authors, as well as the ways it is currently being used with teens in two states. The authors present qualitative data from their observations of and interviews with the students who created the graphic novel. Further, the article provides information on how educators can teach students to create their own comics and graphic novels.
Feasibility of a nanomaterial‐tissue patch for vascular and cardiac reconstruction
Authors: Ostdiek Allison M. , Ivey Jan R. , Hansen Sarah A. , Gopaldas Raja , Grant Sheila A. 
Published: April 2015

AbstractVascular and cardiac reconstruction involves the use of biological patches to treat trauma and defects. An in vivo study was performed to determine the remodeling and biologic effects of novel nanostructured vascular patches with and without gold nanoparticles. Porcine vascular tissue was decellularized and conjugated with gold nanoparticles to evaluate if integration would occur while avoiding rupture and stenosis. Swine underwent a bilateral patch angioplasty of the carotid arteries with experimental patches on the right and control patches of bovine pericardium on the left. Animals were sacrificed after surgery and at 3 and 9 weeks. Ultrasound was performed during surgery, every 3 weeks, and before euthanasia. Endothelial regeneration was examined using Evans Blue dye and histology using Trichrome and H&E. There was a 100% success rate of implantation with 0% mortality. All patches were patent on ultrasound. At 3 weeks, experimental patches had regenerating endothelial cell growth and normal healing responses. At 9 weeks, the experimental patches demonstrated excellent integration. Histology demonstrated cellular in‐growth into the experimental patches and no major immune reactions. This is one of the first studies to demonstrate the feasibility of nanomaterial‐tissue patches for vascular and cardiac reconstruction. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 449–457, 2016.
Use of Auxiliary Functions for Construction of Series Expansion Relations of Noninteger Slater Functions in Standard Convention
Authors: Guseinov I. I. 
Published: April 2015

AbstractUsing complete orthonormal sets of ψ (α*) ‐self‐frictional exponential type orbitals (ψ (α*) ‐SFETOs) and Qq‐noninteger auxiliary functions (Qq‐NIAFs) introduced by the author, the combined formulas for the one‐ and two‐center one‐range addition theorems of χ‐noninteger Slater type orbitals (χ‐NISTOs) with arbitrary values of distances between centers Rab (for Rab = 0 and Rab ≠ 0), and of integer (for α* = α, –∞ < α ≤ 2) and noninteger (for α* ≠ α, –∞ < α* < 3) self‐frictional (SF) quantum numbers are suggested. The presented relations for the one‐range addition theorems can be useful tools especially in the electronic structure studies of atoms, molecules and solids when χ‐NISTOs are employed as basis functions.
Polyethylene Glycol Functionalized Magnetic Dicationic Ionic Liquids as a Novel Catalyst and Their Application in Ring Opening of Epoxides in Water
Authors: Godajdar Bijan Mombeni , Mombeni Sare 
Published: April 2015

AbstractA simple and environmentally benign protocol for the aqueous synthesis of 1,2‐azidoalcohols via regioselective ring opening of 1,2‐epoxides using PEG‐MDIL as a novel magnetic phase transfer catalyst is described. The catalyst was studied by UV spectroscopy, IR spectroscopy, and thermogravimetric analysis. The reactions occur in water and furnish the corresponding azidoalcoholes in high yields. No evidence for the formation of by‐product and the products were obtained in pure form without further purification.
Development of Simple Electrochemical Sensor for Selective Determination of Methadone in Biological Samples Using Multi‐walled Carbon Nanotubes Modified Pencil Graphite Electrode
Authors: Alipour Esmaeel , Majidi Mir Reza , Hoseindokht Omid 
Published: April 2015

AbstractThe electrochemical sensor was developed for determination of methadone (MTD) using multi‐walled carbon nanotubes (MWCNT) modified pencil graphite electrode (MWCNT‐PGE). It was found that the oxidation peak current of MTD at the MWCNT‐PGE was greatly improved compared with that of the bare‐PGE. At the MWCNT‐PGE, well‐defined anodic peak of MTD was observed at about 0.7 V (in pH 7 solution). The influence of several parameters on the determination of MTD was investigated. At optimum experimental conditions, differential pulse voltammetry (DPV) was used for determination of MTD, which exhibited a linear calibration graph of Ip versus MTD concentration in the range of 0.1–15 µM with a correlation coefficient of 0.9992. The calculated detection limit for S/N = 3 was 87 nM. It has been shown that the peaks obtained for oxidation of ascorbic acid (AA), uric acid (UA) and MTD in their mixture could be well resolved by differential pulse voltammetry, permitting us to develop a sensitive and selective electrochemical sensor for determination of MTD in the presence of AA and UA. Finally, MWCNT‐PGE was used for determination of MTD in biological samples, such as human serum and urine, using the standard addition procedure and the results were quite promising.
Knoevenagel‐Michael‐cyclocondensation Tandem Reaction of Malononitrile, Various Aldehydes and Dimedone Catalyzed by Sulfonic Acid Functionalized Pyridinium Chloride as a New Ionic Liquid and Catalyst
Authors: Zolfigol Mohammad Ali , Khazaei Ardeshir , Moosavi‐Zare Ahmad Reza , Afsar Javad , Khakyzadeh Vahid , Khaledian Omid 
Published: April 2015

AbstractNew ionic liquid sulfonic acid functionalized pyridinium chloride[Pyridine–SO3H]Cl was used for the synthesis of tetrahydrobenzo[b]pyran derivatives by the one‐pot three component condensation reaction of various aldehydes, dimedone and malononitrile at 95 ºC under solvent‐free conditions.
Catalytic Reduction of p‐Nitrophenol and Hexacyanoferrate (III) by Borohydride Using Green Synthesized Gold Nanoparticles
Authors: Reddy G. Bhagavanth , Ramakrishna D. , Madhusudhan A. , Ayodhya D. , Venkatesham M. , Veerabhadram G. 
Published: April 2015

AbstractA simple and green approach for the synthesis of well‐stabilized gold nanoparticles (AuNPs) using gum Acacia (GA) is presented here. The gum acacia acts as the reductant and stabilizer. The synthesized gold nanoparticles were characterized by using ultraviolet visible (UV‐Vis), fourier transform infrared spectroscopy (FTIR), x‐ray diffraction (XRD), dynamic light scattering (DLS) and transmission electron microscopy (TEM) techniques. The UV‐Vis study revealed a distinct surface plasmon resonance at 520 – 550 nm, due to the formation of AuNPs. FTIR analysis showed the evidence that –OH groups present in the gum matrix were responsible in reducing the tetra chloroauric acid into AuNPs. XRD studies confirmed the formation of well crystalline nanoparticles with fcc structure and the particle size ranges from 4 – 29 nm, as indicated by TEM analysis. The synthesized gold nanoparticles exhibited homogeneous catalytic activity. The two model reactions studied were the reduction of p‐nitro phenol and the reduction of hexacyanoferrate (III) by borohydride ions. Both the reactions were monitored by UV‐Vis spectroscopy. The kinetic investigations were carried out for the AuNPs‐catalyzed reactions at different temperatures and different amount of catalyst.
Synthesis and Characterization of (2E,2 E)‐3,3‐((9,9‐diocyl‐9H‐flourene‐2,7‐diyl)bis(4,1‐phenylene))bis(2‐cyanoacylic acid) as a Symmetrical Metal‐free Organic Dye
Authors: Hesari Z. , Hadavand B. Shirkavand , Hashemi M. Mahmoodi 
Published: April 2015

AbstractIn this study a novel symmetrical metal‐free organic dye for applications in dye‐sensitized solar cells (DSSCs) was synthesized. This dye (D) was designed with A–π–D–π–A framework and synthesized with 9,9‐dioctylfluorene as electron donor, phenylene as π‐spacer and cyanoacetic acid as electron acceptor. The chemical structure of product was determined using UV‐Vis, FT‐IR, CNMR, HNMR spectroscopy techniques. The presence of a phenylene π‐bridge between the donor and the acceptor units and the di‐anchoring moieties in this structure led to enhancement of conjugation lengths and molar extinction coefficient (ε) that is promising for further improvement of the conversion efficiency of DSSCs.
Synthesis and Characterization of Novel Polyamines Containing Different Substitute Groups Via Chemical Oxidative Polymerization
Authors: Senol Dilek , Kaya ismet 
Published: April 2015

AbstractIn this study, polymers of substitute aromatic amine compounds were synthesized by chemical oxidative polycondensation in aqueous alkaline medium using NaOCl as oxidant. The structures of synthesized compounds were confirmed by FT‐IR, UV‐Vis and NMR analyses. The characterizations of synthesized compounds were made by fluorescence, TG‐DTA, DSC, scanning electron microscopy (SEM) and Brunauer‐Emmett‐Teller (BET) surface area measurements. In addition, electrochemical and electrical conductivity values of compounds were carried out with cyclic voltammetry (CV) and four points probe technique measurements, respectively. Synthesized polymers viewed structural change, optical, electrochemical and thermal differences.
Zero‐valent iron mediated degradation of sertraline – effect of H2O2 addition and application to sewage treatment plant effluent
Authors: de Lima Perini João Angelo , Fernandes Pupo Nogueira Raquel 
Published: April 2015

AbstractBACKGROUNDSertraline (SER) is a widely used antidepressant persistent in sewage treatment plant (STP) effluents. Zero‐valent iron (ZVI) has been studied for degradation of organic contaminants. However, it usually results in poor mineralization efficiency. The effect of H2O2 on ZVI mediated degradation of SER was studied and compared with sole ZVI and the homogeneous Fenton process.RESULTSThe effect of ZVI dose on SER degradation was different with 20 and 200 mesh particle sizes. The degradation rate was improved as the dose of larger particle (20 mesh) was increased, while no significant variation was observed with smaller particle (200 mesh). The SER degradation was hindered by the high Fe2+/H2O2 ratio as well as the sharp increase of pH when high ZVI doses or small particles were used. The addition of H2O2 (5 mmol L−1) to the ZVI system greatly improved SER degradation and mineralization even at low ZVI dose (0.5 g L−1). SER could be efficiently degraded in a STP effluent mediated by ZVI (20 mesh), especially when H2O2 was employed.CONCLUSIONSThe potential of the ZVI/H2O2 process for degradation of SER in effluents from an STP was demonstrated, showing a significant improvement of target contaminant degradation and dissolved organic carbon (DOC) removal. © 2015 Society of Chemical Industry