bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: A Regioselective Facile Synthesis of Furo[3,4‐b]carbazolones: Application to the Total Synthesis of Mafaicheenamine E and Claulansine D.
Authors: Mal Dipakranjan , Roy Joyeeta
Published: September 2015

Using a chemoselective reductive cyclization procedure, naphto[2,3‐c]furanone (V) and furo[3,4‐b]carbazolones (VIII) become accessible.
ChemInform Abstract: Synthesis of Diverse Di‐ to Penta‐Substituted 1,2‐Dihydropyridine Derivatives from Gold(I)‐Catalyzed Intramolecular Addition of Tertiary Enamides to Alkynes.
Authors: Zhang Xingyi , Xu Xin‐Ming , Zhao Liang , You Jingsong , Zhu Jieping , Wang Mei‐Xiang
Published: September 2015

The 6‐endo‐dig cyclization of 3‐aza‐1,5‐enynes provides a wide variety of 1,2‐dihydropyridine derivatives in high yields.
ChemInform Abstract: Asymmetric Syntheses of 3,4‐Disubstituted Tetrahydroquinoline Derivatives Using (+)‐Sparteine‐Mediated Electrophilic Substitution.
Authors: Choi Yun Soo , Kang Kyoung Hee , Park Yong Sun
Published: September 2015

A novel methodology for the asymmetric synthesis of trans‐3,4‐diaryl‐substituted tetrahydroquinolines via sparteine‐assisted stereoselective lithiation of o‐substituted N‐pivaloylanilines (I), kinetic resolution of epoxides in substitution and a stereospecific Mitsunobu cyclization is developed.
ChemInform Abstract: Organocatalytic Asymmetric C—H Vinylation and Arylation of N‐Acyl Tetrahydroisoquinolines.
Authors: Liu Xigong , Sun Shutao , Meng Zhilin , Lou Hongxiang , Liu Lei
Published: September 2015

The metal‐free process can be applied to a broad spectrum of substrates to produce the target compounds with excellent enantioselectivity.
ChemInform Abstract: The Ruegheimer—Burrows Reaction Revisited: Facile Preparation of 4‐Alkylisoquinolines and 3,5‐Dialkylpyridines from (Partially) Saturated Amines.
Authors: Platonova Alena Yu. , Seidel Daniel
Published: September 2015

Reinvestigation of the title reaction reveals that benzoic acid efficiently promotes condensation of amines, such as piperidine and quinolines, with aromatic aldehydes, resulting in amine β‐functionalization and aromatization.
ChemInform Abstract: Preparation of Substituted Phenanthridines from the Coupling of Aryldiazonium Salts with Nitriles: A Metal Free Approach.
Authors: Ramanathan Mani , Liu Shiuh‐Tzung
Published: September 2015

The procedure can be applied to various substituted aryldiazonium tetrafluoroborates and aliphatic or aromatic nitriles.
ChemInform Abstract: Solvent‐Free Synthesis of Novel Benzodiazepine Derivatives by a Three‐Component Base‐Catalyzed Reaction of Isatoic Anhydride, a Primary Amine and Chloroacetyl Chloride.
Authors: Seydey Mohsen Khalilpour , Rezaei Zahra , Homami Seyed Saied
Published: September 2015

Poly(dimethylaminoethyl acrylamide)‐modified magnetic iron oxide nanoparticles are used as a catalyst in a three‐component two‐step synthesis of benzodiazepine derivatives of type (IV).
ChemInform Abstract: Synthesis and Cytotoxic Activity of [Benzo[b][1,4]oxazepino[7,6,5‐de]quinolin‐2‐yl]‐1,3‐tropolones.
Authors: Bang Duong Nghia , Sayapin Yurii A. , Lam Hoang , Duc Nguyen Dang , Komissarov Vitaly N.
Published: September 2015

Three title compounds of type (VIII) or (IX) are prepared, and the inhibitory activity of (IV) and (VIII) against epithelial and breast cancer cells is determined with (VIII) showing the best results.
ChemInform Abstract: Novel 2,6‐Disubstituted Phenylboronic Compounds — Synthesis, Crystal Structures, Solution Behavior and Reactivity.
Authors: Adamczyk‐Wozniak Agnieszka , Ejsmont Krzysztof , Gierczyk Blazej , Kaczorowska Ewa , Matuszewska Alicja , Schroeder Grzegorz , Sporzynski Andrzej , Zarychta Bartosz
Published: September 2015

Reductive cyclization of 2,6‐diformylbenzeneboronic acid gives a (hydroxymethyl)benzoxaborole.
ChemInform Abstract: Chemoselective Silylative Reduction of Conjugated Nitriles under Metal‐Free Catalytic Conditions: β‐Silyl Amines and Enamines.
Authors: Gandhamsetty Narasimhulu , Park Juhyeon , Jeong Jinseong , Park Sung‐Woo , Park Sehoon , Chang Sukbok
Published: September 2015

In the presence of excess diphenyl and triphenyl silane acryl nitriles are reduced to silyl amines and N‐disilyl enamines.
ChemInform Abstract: Manganese‐Mediated Alkene Chloro‐phosphinoylation.
Authors: Richard Vincent , Fisher Henry C. , Montchamp Jean‐Luc
Published: September 2015

The bisfunctionalization of alkenes with phosphorous and chlorine to afford β‐chloro‐phosphinoyl compounds is described.
ChemInform Abstract: Non‐Aqueous Metathesis as a General Approach to Prepare Nanodispersed Materials: Case Study of Scheelites.
Authors: Afanasiev Pavel
Published: September 2015

Metathesis of precursor salts in non‐aqueous liquids as a general approach to the preparation of inorganic nanoparticles is demonstrated by the synthesis of scheelites AMO4 (A: Ba, Sr, Ca; M: Mo, W).
ChemInform Abstract: Preparation and Functionalization of Gold Nanoparticles
Authors: Capek Ignac
Published: September 2015

Review: 67 refs.
ChemInform Abstract: Monomeric Dinitrosyl Iron Complexes: Synthesis and Reactivity
Authors: Tran Camly T. , Skodje Kelsey M. , Kim Eunsuk
Published: September 2015

Review: 111 refs.
ChemInform Abstract: Radical‐Mediated Three‐Component Reaction: A Study Toward the Total Synthesis of Resiniferatoxin
Authors: Urabe Daisuke
Published: September 2015

Review: 77 refs.
ChemInform Abstract: Green Chemical Synthesis of Bisphosphonic/Dronic Acid Derivatives
Authors: Keglevich Gyorgy , Grun Alajos , Kovacs Rita , Garadnay Sandor , Greiner Istvan
Published: September 2015

Review: 10 refs.
ChemInform Abstract: Synthesis of Quinolines and Acridines by the Reaction of 2‐(Perfluoroalkyl)anilines with Lithium and Grignard Reagents
Authors: Strekowski Lucjan , Zhang Jianguo , Saczewski Jaroslaw , Wolinska Ewa
Published: September 2015

Review: 50 refs.
ChemInform Abstract: Molecular Dynamics Simulations of Supported Metal Nanocatalyst Formation by Plasma Sputtering
Authors: Brault Pascal , Neyts Erik C.
Published: September 2015

Review: 97 refs.
Reuse of Air for Return Activated Sludge Pumping in Submerged Membrane Bioreactors
Authors: Starke Christina , Bérubé Pierre R.
Published: September 2015

The reuse of air added for gas sparging to airlift return activated sludge (RAS) in a membrane bioreactor (MBR) was investigated. Numerical modeling suggests that the RAS conveyance requirements in an MBR could be met for systems with a treatment capacity of ≤3.8 · 106 L d−1, and potentially for larger MBRs, depending on the system design (i.e., U‐shaped rather than linear systems). Pilot scale validation confirmed that airlift could be used to meet the RAS conveyance requirements. Optimal conditions were obtained for pilot scale systems with square air collectors, intermediate/large air collector angles, greater depth of submergence and individual tubing to redirect the airlifted flow. Implementation of airlift RAS conveyance in small to intermediate size MBRs can results in a reduction of approximately 20 % in operating costs.
Discovery of Quinoline‐Derived Trifluoromethyl Alcohols, Determination of Their in vivo Toxicity and Anticancer Activity in a Zebrafish Embryo Model
Authors: Sittaramane Vinoth , Padgett Jihan , Salter Philip , Williams Ashley , Luke Shauntelle , McCall Rebecca , Arambula Jonathan F. , Graves Vincent B. , Blocker Mark , Van Leuven David , Bowe Keturah , Heimberger Julia , Cade Hannah C. , Immaneni Supriya , Shaikh Abid
Published: September 2015

In this study the rational design, synthesis, and anticancer activity of quinoline‐derived trifluoromethyl alcohols were evaluated. Members of this novel class of trifluoromethyl alcohols were identified as potent growth inhibitors in a zebrafish embryo model. Synthesis of these compounds was carried out with an sp3‐C−H functionalization strategy of methyl quinolines with trifluoromethyl ketones. A zebrafish embryo model was also used to explore the toxicity of ethyl 4,4,4‐trifluoro‐3‐hydroxy‐3‐(quinolin‐2‐ylmethyl)butanoate (1), 2‐benzyl‐1,1,1‐trifluoro‐3‐(quinolin‐2‐yl)propan‐2‐ol (2), and trifluoro‐3‐(isoquinolin‐1‐yl)‐2‐(thiophen‐2‐yl)propan‐2‐ol (3). Compounds 2 and 3 were found to be more toxic than compound 1; apoptotic staining assays indicated that compound 3 causes increased cell death. In vitro cell proliferation assays showed that compound 2, with an LC50 value of 14.14 μm, has more potent anticancer activity than cisplatin. This novel class of inhibitors provides a new direction in the discovery of effective anticancer agents.
Application kernels: HPC resources performance monitoring and variance analysis
Authors: Simakov Nikolay A. , White Joseph P. , DeLeon Robert L. , Ghadersohi Amin , Furlani Thomas R. , Jones Matthew D. , Gallo Steven M. , Patra Abani K.
Published: September 2015

Application kernels are computationally lightweight benchmarks or applications run repeatedly on high performance computing (HPC) clusters in order to track the Quality of Service (QoS) provided to the users. They have been successful in detecting a variety of hardware and software issues, some severe, that have subsequently been corrected, resulting in improved system performance and throughput. In this work, the application kernels performance monitoring module of eXtreme Data Metrics on Demand (XDMoD) is described. Through the XDMoD framework, the application kernels have been run repetitively on the Texas Advanced Computing Center's Stampede and Lonestar4 clusters for a total of over 14,000 jobs. This provides a body of data on the HPC clusters operation that can be used to statistically analyze how the application performance, as measured by metrics such as execution time and communication bandwidth, is affected by the cluster's workload. We discuss metric distributions, carry out regression and correlation analyses, and use a PCA study to describe the variance and relate the variance to factors such as the spatial distribution of the application in the cluster. Ultimately, these types of analyses can be used to improve the application kernel mechanism, which in turn results in improved QoS of the HPC infrastructure that is delivered to the end users. Copyright © 2015 John Wiley & Sons, Ltd.
Distributed CTL model checking using MapReduce: theory and practice
Authors: Bellettini Carlo , Camilli Matteo , Capra Lorenzo , Monga Mattia
Published: September 2015

The recent extensive availability of ‘cloud’ computing platforms is very appealing for the formal verification community. In fact, these platforms represent a great opportunity to run massively parallel jobs and analyze ‘big data’ problems, although classical formal verification tools and techniques must undergo a deep technological transformation to take advantage of the available powerful architectures. A distributed approach to verification of computation tree logic formulas on very large state spaces is described. The approach exploits and integrates our parametric state–space builder, designed to ease the adoption of ‘big data’ platforms. The whole framework adopts a MAPREDUCEapproach as the core computational model and can be tailored to different modeling formalisms. This paper includes proofs of correctness, a short theoretical discussion about complexity, and reports a practical experience with some benchmarking Petri net models. The outcomes of several tests are presented, thus showing the convenience of the proposed approach. Copyright © 2015 John Wiley & Sons, Ltd.
Parallel similarity joins on massive high‐dimensional data using MapReduce
Authors: Ma Youzhong , Meng Xiaofeng , Wang Shaoya
Published: September 2015

In this paper, we focus on high‐dimensional similarity join (HDSJ) using MapReduce paradigm. As the volume of the data and the number of the dimensions increase, the computation cost of HDSJ will increase exponentially. There is no existing effective approach that can process HDSJ efficiently, so we propose a novel method called symbolic aggregate approximation (SAX)‐based HDSJ to deal with the problem. SAX is the abbreviation of symbolic aggregate approximation that is a dimensionality reduction technique and widely used in time series processing, we use SAX to represent the high‐dimensional vectors in this paper and reorganize these vectors into groups based on their SAX representations. For the very high‐dimensional vectors, we also propose an improved SAX‐based HDSJ approach. Finally, we implement SAX‐based HDSJ and improved SAX‐based HDSJ on Hadoop‐0.20.2 and perform comprehensive experiments to test the performance, we also compare SAX‐based HDSJ and improved SAX‐based HDSJ with the existing method. The experiment results show that our proposed approaches have much better performance than that of the existing method. Copyright © 2015 John Wiley & Sons, Ltd.
Lessons learned implementing a science gateway for hydro‐meteorological research
Authors: D'Agostino Daniele , Danovaro Emanuele , Clematis Andrea , Roverelli Luca , Zereik Gabriele , Parodi Antonio , Galizia Antonella
Published: September 2015

A full hydrometeorological (HM) simulation, from rainfall to impact on urban areas, is a multidisciplinary job, which relies on the execution of a workflow composed of complex and heterogeneous model engines. Moreover, the accuracy of the simulation is strongly dependent on an extensive set of configuration parameters, which have to be selected in a consistent way among the models. Within the Distributed Research Infrastructure for Hydro‐Meteorology project, a Web‐based science gateway was developed with the aim to support HM researchers in designing, executing, and managing HM experiments. The core of this science gateway is the portal, which takes care of generating all the configuration files and handles the execution of simulation steps on a heterogeneous computing infrastructure composed of high‐performance computing, Grid resources, and Cloud resources. This paper presents technological insights about the implementation of the portal, with an analysis of the adopted technologies and infrastructures. Our experience highlights the need of coherent policies in the management of data, computational resources, and software components that represent the ecosystem to develop science gateways. Copyright © 2015 John Wiley & Sons, Ltd.
2′‐Methoxyacetophenone: An Efficient Photosensitizer for Cyclobutane Pyrimidine Dimer Formation
Authors: Liu Lizhe , Pilles Bert M. , Reiner Anne M. , Gontcharov Julia , Zinth Wolfgang
Published: September 2015

Stationary and time‐resolved experiments show that 2′‐methoxyacetophenone (2‐M) is an interesting compound for the investigation of triplet states in thymine samples. Time‐resolved emission experiments show that the fluorescence lifetime of 2‐M is 660 ps. A similar time constant of 680 ps is found in transient IR experiments. The data indicate efficient intersystem crossing (≈97 %) from the fluorescent singlet state to the triplet state. The lifetime of the triplet state of 2‐M dissolved in D2O at room temperature and ambient oxygen concentration is 400 ns. 2‐M has a strong absorption in the UV‐A range and can photosensitize the triplet state of a thymidine dinucleotide with light at a wavelength of 320 nm. The experiments show that 2‐M is well‐suited for time‐resolved experiments on the triplet‐sensitizing process.
The Influence of Surface Modification on the Photoluminescence of CdTe Quantum Dots: Realization of Bio‐Imaging via Cost‐Effective Polymer
Authors: Jin Gan , Jiang Li‐Ming , Yi Dong‐Mei , Sun Hai‐Zhu , Sun Hong‐Chen
Published: September 2015

To impart biocompatibility, stability, and specificity to quantum dots (QDs)—and to reduce their toxicity—it is essential to carry out surface modification. However, most surface‐modification processes are costly, complicated, and time‐consuming. In addition, the modified QDs often have a large size, which leads to easy aggregation in biological environments, making it difficult to excrete them from in vivo systems. To solve these problems, three kinds of conventional polymers, namely, polyvinyl alcohol (PVA, neutral), sodium polystyrene sulfonate (PSS, negative charged), and poly(diallyl dimethyl ammonium chloride) (PDDA, positive charged) were selected to modify the surface of QDs at low cost via a simple process in which the size of the QDs was kept small after modification. The effect of polymer modification on the photoluminescence (PL) properties of the QDs was systematically investigated. High quantum yields (QYs) of 65 % were reached, which is important for the realization of bio‐imaging. Then, the cytotoxicity of CdTe QD–polymer composites was systematically investigated via MTT assay using the Cal27 and HeLa cell lines, especially for high concentrations of QD–polymer composites in vitro. The experimental results showed that the cytotoxicity decreased in the order CdTe‐PDDA>CdTe>CdTe‐PSS>CdTe‐PVA, indicating that PSS and PVA can reduce the toxicity of the QDs. An obvious cytotoxicity of CdTe‐PVA and CdTe‐PSS was present until 120 h for the Cal27 cell line and until 168 h for the HeLa cell line. At last, the Cal27 cell line was selected to realize bio‐imaging using CdTe‐PSS and CdTe‐PVA composites with different emission colors under one excitation wavelength.
Reversible Carbene Formation in the Ionic Liquid 1‐Ethyl‐3‐Methylimidazolium Acetate by Vaporization and Condensation
Authors: Kar Bishnu Prasad , Sander Wolfram
Published: September 2015

The role of N‐heterocyclic carbenes in the chemistry of ionic liquids based on imidazolium salts has long been discussed. Here, we present experimental evidence that 1‐ethyl‐3‐methylimidazolium‐2‐ylidene (EMIm) can coexist with its protonated imidazolium cation (EMImH+) at low temperatures. If the vapor of the ionic liquid [EMImH+][AcO−] is trapped in solid argon or nitrogen at 9 K, only acetic acid (AcOH) and the carbene, but no ionic species, are found by IR spectroscopy. This indicates that during the evaporation of [EMImH+][AcO−] proton transfer occurs to form the neutral species. If the vapor of [EMImH+][AcO−] is trapped at 9 K as film in the absence of a host matrix, a solid consisting of EMImH+, EMIm, AcO−, and AcOH is formed. During warming to room temperature the proton transfer in the solid to form back the IL [EMImH+][AcO−] can be monitored by IR spectroscopy. This clearly demonstrates that evaporation and condensation of the IL [EMImH+][AcO−] results in a double proton transfer, and the carbene EMIm is only metastable even at low temperatures.
Measuring the Absorption Rate of CO2 in Nonaqueous CO2‐Binding Organic Liquid Solvents with a Wetted‐Wall Apparatus
Authors: Mathias Paul M. , Zheng Feng , Heldebrant David J. , Zwoster Andy , Whyatt Greg , Freeman Charles M. , Bearden Mark D. , Koech Phillip
Published: September 2015

The kinetics of the absorption of CO2 into two nonaqueous CO2‐binding organic liquid (CO2BOL) solvents were measured at T=35, 45, and 55 °C with a wetted‐wall column. Selected CO2 loadings were run with a so‐called “first‐generation” CO2BOL, comprising an independent base and alcohol, and a “second‐generation” CO2BOL, in which the base and alcohol were conjoined. Liquid‐film mass‐transfer coefficient (k′g) values for both solvents were measured to be comparable to values for monoethanolamine and piperazine aqueous solvents under a comparable driving force, in spite of far higher solution viscosities. An inverse temperature dependence of the k′g value was also observed, which suggests that the physical solubility of CO2 in organic liquids may be making CO2 mass transfer faster than expected. Aspen Plus software was used to model the kinetic data and compare the CO2 absorption behavior of nonaqueous solvents with that of aqueous solvent platforms. This work continues our development of the CO2BOL solvents. Previous work established the thermodynamic properties related to CO2 capture. The present paper quantitatively studies the kinetics of CO2 capture and develops a rate‐based model.
Higher risk for incident heart failure and cardiovascular mortality among community‐dwelling octogenarians without pneumococcal vaccination
Authors: Ahmed Momanna B. , Patel Kanan , Fonarow Gregg C. , Morgan Charity J. , Butler Javed , Bittner Vera , Kulczycki Andrzej , Kheirbek Raya E. , Aronow Wilbert S. , Fletcher Ross D. , Brown Cynthia J. , Ahmed Ali
Published: September 2015

Aims

Octogenarians have the highest incidence of heart failure (HF) that is not fully explained by traditional risk factors. We explored whether lack of pneumococcal vaccination is associated with higher risk of incident HF among octogenarians.

Methods and results

In the Cardiovascular Health Study (CHS), 5290 community‐dwelling adults, ≥65 years of age, were free of baseline HF and had data on pneumococcal vaccination. Of these, 851 were octogenarians, of whom, 593 did not receive pneumococcal vaccination. Multivariable‐adjusted hazard ratios (aHR) and 95% confidence intervals (CI) for associations of lack of pneumococcal vaccination with incident HF and other outcomes during 13 years of follow‐up were estimated using Cox regression models, adjusting for demographics and other HF risk factors including influenza vaccination. Octogenarians had a mean (±SD) age of 83 (±3) years; 52% were women and 17% African American. Overall, 258 participants developed HF and 662 died. Lack of pneumococcal vaccination was associated with higher relative risk of incident HF (aHR, 1.37; 95% CI, 1.01–1.85; P = 0.044). There was also higher risk for all‐cause mortality (aHR, 1.23; 95% CI, 1.02–1.49; P = 0.028), which was mostly driven by cardiovascular mortality (aHR, 1.45; 95% CI, 1.06–1.98; P = 0.019). Octogenarians without pneumococcal vaccination had a trend toward higher risk of hospitalization due to pneumonia (aHR, 1.34; 95% CI, 0.99–1.81; P = 0.059). These associations were not observed among those 65–79 years of age.

Conclusions

Among community‐dwelling octogenarians, lack of pneumococcal vaccination was associated with a significantly higher independent risk of incident HF and mortality, and trend for higher pneumonia hospitalization.
γδ T cells come to stay: Innate skin memory in the Aldara model
Authors: Prinz Immo , Sandrock Inga
Published: September 2015

The term immunological memory has long been a trademark restricted to adaptive lymphocytes such as memory B cells and plasma cells as well as memory CD8+ αβ T cells. In recent years, innate lymphocytes such as NK cells have also been shown to adapt to their environment by antigen‐specific expansion and selective survival. However, whether γδ T cells mount comparable memory responses to pathogenic stimuli is less well understood. In this issue of European Journal of Immunology, Hartwig et al. [Eur. J. Immunol. 2015. 45: 3022–3033] identify a subset of IL‐17‐producing γδ T cells that are capable of establishing long‐lived memory in the skin of mice exposed to imiquimod in the Aldara psoriasis model. These γδ T cells uniformly express a Vγ4+Vδ4+ TCR. They produce IL‐17A/F and persist in the dermis for long periods of time, also at untreated distal sites. Upon secondary challenge, experienced Vγ4+Vδ4+ cells show enhanced effector functions and mediate exacerbated secondary inflammation. These findings showcase innate γδ T‐cell memory that uses a single conserved public TCR combination. Furthermore, they provide mechanistic insight to the observed psoriatic relapses in patients in response to topical treatment with imiquimod.
Influence of the Crystal Structure on the Luminescence Properties of Mixed Eu,La–(1,10‐Phenanthroline) Complexes
Authors: Yang Ting‐Hai , Fu Lianshe , Ferreira Rute A. S. , Nolasco Mariela M. , Rocha João , Carlos Luís D. , Shi Fa‐Nian
Published: September 2015

A series of europium Eu‐ and La‐doped complexes with two different crystal structures, namely, EuxLa1–x(phen)2(NO3)3 [phen = 1,10‐phenanthroline, x = 1.0 (1), 0.88 (2), 0.73 (3), and 0.52 (4)] and {[EuxLa1–x(phen)2(H2O)2(NO3)2](NO3)·2(phen)(H2O)} [x = 0.28 (5) and 0.0 (6)], were synthesized in aqueous solution by using different Eu/La ratios.The complexes were characterized by single‐crystal and powder X‐ray diffraction, Fourier transform infrared spectroscopy, elemental analysis, thermogravimetry, and scanning electron microscopy. Compounds 1–4 and 5, 6 were obtained for Eu/La molar ratios higher than 5:5 and smaller than 3:7, respectively. The photoluminescence properties of these compounds depend on the crystal structure, which is determined by the Eu/La reactant ratio. Complexes 1–4 exhibit a quantum efficiency (η = 55 %) and quantum yield (q = 31 %) higher than 5 (η = 23 % and q = 6 %). The photophysical properties assessed by using the LUMPAC software are in good accord with the experimental values, particularly, the calculated (26 %) and measured emission quantum yields (31 %; excitation at the ligands at 255 nm).
Host‐Sensitized Photoluminescence and Coordination Environment Evolution in Ba6(Bi1–xTbx)9B79O138 (0 ≤ x ≤ 1)
Authors: Li Qiaoqi , Cong Rihong , Gao Wenliang , Yang Tao
Published: September 2015

Borates are well‐known candidates for optical materials and, here, we are particularly interested in Ba6Bi9B79O138 (BBBO), which has an interesting layered‐type structure and Bi3+‐containing characteristics that has prompt us to explore its host‐sensitized photoluminescence (PL). Solid solutions of BBBO:xTb3+ (0 ≤ x ≤ 1) were prepared and its host‐sensitized photoluminescence was confirmed, which is a result of the efficient Bi3+‐to‐Tb3+ energy transfer. Furthermore, an evolution of the coordination environments of the Bi3+/Tb3+ sites was observed when increasing x. This evolution was found to correlate to the variation of the PL spectra. In particular, the value of the ratio of cyan/green [defined as I(5D4→7F6)/I(5D4→7F5) of Tb3+] was about 0.28 when x < 0.4, and it increased to 0.71 at x = 0.9 and thereafter remained almost constant. Ba6(RE0.3–yBiyTb0.7)9B79O138 (RE = La or Y, 0 ≤ y ≤ 0.3) were also prepared for better understanding of the host‐sensitization effect and in both series, Ba6(RE0.1Bi0.2Tb0.7)9B79O138 show the highest emission.
Metal–Halogen Secondary Bonding in a 2,5‐Dichlorohydroquinonate Cobalt(II) Complex: Insight into Substrate Coordination in the Chlorohydroquinone Dioxygenase PcpA
Authors: Schofield Jeremy A. , Brennessel William W. , Urnezius Eugenijus , Rokhsana Dalia , Boshart Monica D. , Juers Douglas H. , Holland Patrick L. , Machonkin Timothy E.
Published: September 2015

Despite the unprecedented selectivity of the hydroquinone ring‐cleaving dioxygenase PcpA for ortho‐chlorohydroquinones, there are no examples of an ortho‐chlorohydroquinone bound to a transition‐metal complex. Herein, the synthesis and characterization of (TpPh2Co)2(μ‐2,5‐dichlorohydroquinonate), for which TpPh2 is tris(3,5‐diphenylpyrazolyl)borate, were explored. The dianionic 2,5‐dichlorohydroquinonate bridges two (TpPh2Co) moieties and coordinates each cobalt(II) center through the oxygen and chlorine atoms of the chlorohydroquinone. The Co–Cl distance of 2.778 Å shows the characteristics of a metal–halogen secondary bond, as we previously showed in ortho‐halophenolate complexes. This compound represents the first example of metal–halogen secondary bonding with a halohydroquinone and, thus, provides a potential structural model for selective substrate binding to the metal center in PcpA.
A Ferricyanide‐mediated Activated Sludge Bioassay for Determination of the Toxicity of Water
Authors: Ma Haipeng , Yong Daming , Kim Hojong , Zhang Zhijia , Ma Shenghua , Han Xiaojun
Published: September 2015

Activated sludge was successfully exploited as the medium in the fast ferricyanide‐mediated toxicity (FM‐TOX) bioassay. The mediated biosensor toxicity assessment using activated sludge greatly simplified the testing process and improved detection sensitivity. The principle of the method is that the respiration of bacteria in the activated sludge is inhibited by the pollutants, and the extent of the inhibition is related to the concentration of toxicants. A series of experimental conditions (activated sludge concentration, incubation time, reaction temperature and pH of the solution) were optimized in order to increase the sensitivity. Different kinds of toxicants and natural water samples were examined under the best conditions and IC50 values of them were obtained respectively. According to the testing results, a toxicity order was given: Hg2+>Zn2+>Cd2+>Pb2+ for heavy metal ions; 3,5‐DCP>PA>Methanol for organic toxicants and Machete>DDT for pesticides. The detection limits for those pollutants are lower than the values in the national standard. These results confirmed that this sensor may serve as an early warning device for avoiding environmental pollution and affecting public health.
Fabrication of Hierarchical Hollow Manganese Silicate Spheres for the Simultaneous Enhanced Determination of 2‐Aminophenol and 4‐Aminophenol
Authors: Sun Junyong , Shi Zhaoxia , Li Jifan , Liu Bingbing , Gan Tian
Published: September 2015

We developed a new electrochemical method for the simultaneous determination of 2‐aminophenol (2‐AP) and 4‐aminophenol (4‐AP) based on hollow manganese silicate spheres. The hierarchical hollow structure of manganese silicate submicrometer spheres was formed by the assemblage of numerous nanobubbles, as confirmed by scanning electron microscopy and transmission electron microscopy images. As sensing material for the simultaneous determination of 2‐AP and 4‐AP for the first time, the electrochemical performances of 2‐AP and 4‐AP were studied in detail. The detection limits (S/N=3) for 2‐AP and 4‐AP were as low as 18 and 11 nM, respectively.
Could Voltammetry be an Effective Alternative Technique to Study Adsorption Kinetics of Electroactive Metal Ions?
Authors: Araújo Diele A. G. , Faria Ana C. A. , Takeuchi Regina M. , Santos André L.
Published: September 2015

The suitability of LSV to study adsorption kinetics of metal ions was evaluated using Cu2+ adsorption on Amberlite® IR‐120 as a model system. LSV provided results in agreement with conventional batch method with remarkable decreasing on analysis time and reagents consumption, since no adsorbent/adsorbate separation is required. Adsorption curves can be obtained in situ using only one portion of adsorbate solution. LSV provides higher temporal resolution for adsorption curves, which is indispensable to evaluate adsorption mechanisms and the performance of new adsorbent materials. Therefore, LSV not only saves time and reagents but also provides better quality of kinetic adsorption data.
Enantioselective column coupled electrophoresis employing large bore capillaries hyphenated with tandem mass spectrometry for ultra‐trace determination of chiral compounds in complex real samples
Authors: Piešťanský Juraj , Maráková Katarína , Kovaľ Marián , Havránek Emil , Mikuš Peter
Published: September 2015

A new multidimensional analytical approach for the ultra‐trace determination of target chiral compounds in unpretreated complex real samples was developed in this work. The proposed analytical system provided high orthogonality due to on‐line combination of three different methods (separation mechanisms), i.e. (1) isotachophoresis (ITP), (2) chiral capillary zone electrophoresis (chiral CZE), and (3) triple quadrupole mass spectrometry (QqQ MS). The ITP step, performed in a large bore capillary (800 μm), was utilized for the effective sample pretreatment (preconcentration and matrix clean‐up) in a large injection volume (1–10 μL) enabling to obtain as low as ca. 80 pg/mL limits of detection for the target enantiomers in urine matrices. In the chiral CZE step, the different chiral selectors (neutral, ionizable, and permanently charged cyclodextrins) and buffer systems were tested in terms of enantioselectivity and influence on the MS detection response. The performance parameters of the optimized ITP – chiral CZE‐QqQ MS method were evaluated according to the FDA guidance for bioanalytical method validation. Successful validation and application (enantioselective monitoring of renally eliminated pheniramine and its metabolite in human urine) highlighted great potential of this chiral approach in advanced enantioselective biomedical applications.
Effects of the boscalid fungicide Filan® on the marine amphipod Allorchestes compressa at environmentally relevant concentrations
Authors: Vu Hung T. , Keough Michael J. , Long Sara M. , Pettigrove Vincent J.
Published: September 2015

Fungicides are widely used in agriculture to control fungal diseases. After application, fungicides can be transported offsite to surface and groundwater and ultimately enter estuarine and marine environments. The presence of fungicides in the marine environment may pose risks to marine organisms, but little is known about fungicide effects on these organisms, especially invertebrates. The present study investigated the effects of the commonly used boscalid fungicide Filan® on life history traits, feeding rate, and energy reserves (lipid, glycogen, and protein content) of the marine amphipod Allorchestes compressa over 6 wk under laboratory conditions. Amphipods were exposed to 3 concentrations of Filan (1 μg, 10 μg, and 40 μg active ingredient [a.i.]/L), with 5 replicates per treatment. Lipid content and reproduction were the most sensitive measures of effect, with lipid content reduced by 53.8% at the highest concentration. Survival, growth, and other energy reserves of amphipods were also negatively affected by Filan, and the effects were concentration dependent. Antennal deformities were incidentally observed on the amphipods at a concentration of 40 μg a.i./L. The results of the present study indicate comprehensive effects of the boscalid fungicide Filan on A. compressa at environmentally relevant concentrations. The decline or absence of A. compressa in marine ecosystems could impair the ecosystem function because of their important role in trophic transfer and nutrient recycling. The authors' results suggest that even though the use of fungicides is often regarded as posing only a minor risk to aquatic organisms, the assessment of their long-term effects is critical. Environ Toxicol Chem 2016;35:1130–1137. © 2015 SETAC
Insights into the nature of uranium target proteins within zebrafish gills after chronic and acute waterborne exposures
Authors: Bucher Guillaume , Mounicou Sandra , Simon Olivier , Floriani Magali , Lobinski Ryszard , Frelon Sandrine
Published: September 2015

New data on the nature of the protein targets of uranium (U) within zebrafish gills were collected after waterborne exposure, with the aim of a better understanding of U toxicity mechanisms. Some common characteristics of the U protein target binding properties were found, such as their role in the regulation of other essential metals and their phosphorus content. In total, 21 potential protein targets, including hemoglobin, are identified and discussed in terms of the literature. Environ Toxicol Chem 2016;35:736–741. © 2015 SETAC
CO/CO2 Study of High Performance La0.3Sr0.7Fe0.7Cr0.3O3–δ Reversible SOFC Electrodes
Authors: Addo P. K. , Molero‐Sanchez B. , Chen M. , Paulson S. , Birss V.
Published: September 2015

In this study, we demonstrate that the La0.3Sr0.7Fe0.7Cr0.3O3–δ (LSFCr) perovskite, examined here as a CO/CO2 fuel electrode material intended for symmetrical, reversible solid oxide fuel cell (RSOFC) applications, is both high performing and stable towards CO2 electrolysis (SOEC mode) and the oxidation of CO (SOFC mode). To demonstrate this, symmetrical LSFCr/GDC/YSZ/GDC/LSFCr cells were evaluated electrochemically by using both DC (cyclic voltammetry (CV) and galvanostatic) and AC (impedance) techniques. The cells were tested at 800 °C using either 90% CO2:10% CO or 70% CO2:30% CO at the fuel electrode and air flowing to the O2 electrode. From the open circuit impedance data, the polarization resistance, measured at 800 °C in a 90% CO2:10% CO and 70% CO2:30% CO gas composition, was 1.3 Ω cm2 and 0.9 Ω cm2, respectively. Both the CV and polarized impedance data showed that the cell performance is higher during the electrolysis of CO2 than for the oxidation of CO. Furthermore, the cell showed a very stable activity during CO2 electrolysis, with a degradation rate of only 0.057 mV h−1 after ca. 135 h of galvanostatic testing at –100 mA cm−2 in 90% CO2:10% CO at 800 °C.
Pedo‐Geochemical Signatures of Archeological Sites in the Tapirapé‐Aquiri National Forest in Marabá, Amazonia, Brazil
Authors: Kern Dirse Clara , Costa Jucilene Amorim , da Silveira Maura Imazio , de Oliveira Elisangela Regina , Frazão Francisco J. Lima , Berredo José Francisco , da Costa Marcondes Lima , Kämpf Nestor
Published: September 2015

The present study aims to interpret the occupation ofterra firme(nonflooded uplands) archeological sites located at Tapirapé‐Aquiri National Forest in the Brazilian state of Pará, through an integrated analysis of pedological, archeological, and geochemical data. We focus on seven archaeological sites, selected among 22 identified in the region. Radiocarbon and thermoluminescence dating indicate distinct periods of occupation over the past ∼6000 years, and the pedo‐geochemical data identify intra‐ and inter‐site differences in soil. Archaeological, chronometric, and pedo‐geochemical data provide a basis for the functional classification of archeological sites found in the region and help to identify specific human activity areas. The results lead us to infer that many of the archeological sites were the result of multiple occupations that left a persistent pedological signature on the landscape.
Tubal ligation and ovarian cancer risk in a large cohort: Substantial variation by histological type
Authors: Gaitskell Kezia , Green Jane , Pirie Kirstin , Reeves Gillian ,   Valerie Beral; on behalf of the Million Women Study Collaborators
Published: September 2015

Histopathological and molecular studies suggest that different histological subtypes (histotypes) of ovarian cancer have different aetiologies. Few studies have been large enough to explore reliably the effect of tubal ligation (sterilization), which has been associated with a reduced overall risk of ovarian cancer, on different tumour histotypes. In a prospective study of 1.1 million UK women without prior cancer or bilateral oophorectomy, 8,035 ovarian cancers occurred during mean follow‐up of 13.8 years. Using a Cox proportional hazards model, we estimated adjusted relative risks of ovarian cancer associated with tubal ligation. Overall, there was substantial heterogeneity in tumour risk associated with tubal ligation for the four main histotypes, serous, endometrioid, mucinous and clear cell (heterogeneity: p < 0.0001). For serous tumours, the most common histotype (n = 3,515), risks differed significantly between high‐grade (RR: 0.77, 95% CI: 0.67–0.89) and low‐grade tumours (RR: 1.13, 95% CI: 0.89–1.42); heterogeneity: p = 0.007. Relative risks were almost halved for endometrioid (n = 690, RR: 0.54, 95% CI: 0.43–0.69) and clear cell tumours (n = 401, RR: 0.55, 95% CI: 0.39–0.77), but there was no association between tubal ligation and mucinous tumours (n = 836, RR: 0.99, 95% CI: 0.84–1.18). For the main tumour histotypes we found little variation of risk by timing of tubal ligation. The significant differences by tumour histotype are unlikely to be due to confounding and are consistent with hypotheses that high‐grade and low‐grade serous tumours have different origins, and that some endometrioid and clear cell tumours might arise from cells and/or carcinogens travelling through the fallopian tubes.
Functional expressions of adenosine triphosphate‐binding cassette transporters during the development of zebrafish embryos and their effects on the detoxification of cadmium chloride and β‐naphthoflavone
Authors: Yin Huancai , Bai Pengli , Miao Peng , Chen Mingli , Hu Jun , Deng Xudong , Yin Jian
Published: September 2015

Adenosine triphosphate‐binding cassette (ABC) transporters, including ABCB, ABCC and ABCG families represent general biological defenses against environmental toxicants in varieties of marine and freshwater organisms, but their physiological functions at differential developmental stages of zebrafish embryos remain undefined. In this work, functional expressions of typical ABC transporters including P‐glycoprotein (Pgp), multiresistance associated protein 1 (Mrp1) and Mrp2 were studied in zebrafish embryos at 4, 24, 48 and 72 h post‐fertilization (hpf). As a result, both the gene expressions and activities of Pgp and Mrps increased with the development of embryos. Correspondingly, 4–72 hpf embryos exhibited an increased tolerance to the toxicity caused by cadmium chloride (CdCl2) and β‐naphthoflavone (BNF) with time. Such a correlation was assumed caused by the involvement of ABC transporters in the detoxification of chemicals. In addition, the assumption was supported by the fact that model efflux inhibitors of Pgp and Mrps such as reversine 205 and MK571 significantly inhibited the efflux of toxicants and increased the toxicity of Cd and BNF in zebrafish embryos. Moreover, exposure to CdCl2 and BNF induced the gene expressions of Pgp and Mrp1 in 72 hpf embryos. Thus, functional expressions of Pgp and Mrps increased with the development of zebrafish embryos, which could cause an increasing tolerance of zebrafish embryos to CdCl2 and BNF. Copyright © 2015 John Wiley & Sons, Ltd.
Smooth muscle tissue engineering in crosslinked electrospun gelatin scaffolds
Authors: Elsayed Yahya , Lekakou Constantina , Labeed Fatima , Tomlins Paul
Published: September 2015

Crosslinked, multi‐layer electrospun gelatin fiber scaffolds with generally ±45 degree fiber orientation have been used to grow human umbilical vein smooth muscle cells (HUVSMCs) to create a vascular tunica media graft. Scaffolds of different fiber diameter (2–5 μm in wet state), pore size, and porosity (16–21% in wet state) were assessed in terms of cell adherence and viability, cell proliferation, and migration in both in‐plane and transverse directions through the scaffold as a function of time under static cell culture conditions. HUVSMC cell viability reached between 80 and 92% for all scaffolds after 9 days in culture. HUVSMCs adhered, elongated, and orientated in the fiber direction, and migrated through a scaffold thickness of 200–235 μm 9 days post‐seeding under static conditions. The best scaffold was then used to assess the tissue engineering of HUVSMCs under dynamic conditions for a rotating, cell seeded, tubular scaffold in the bioreactor containing the culture medium. Dynamic conditions almost doubled the rate of cell proliferation through the scaffold, forming full tissue throughout a scaffold of 250–300 μm thickness 6 days post‐seeding. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 313–321, 2016.
Alterations of the Plasma Peptidome Profiling in Colorectal Cancer Progression
Authors: Bedin Chiara , Crotti Sara , Ragazzi Eugenio , Pucciarelli Salvatore , Agatea Lisa , Tasciotti Ennio , Ferrari Mauro , Traldi Pietro , Rizzolio Flavio , Giordano Antonio , Nitti Donato , Agostini Marco
Published: September 2015

Early detection of colorectal cancer (CRC) remains a challenge. It has been highlighted that the pathological alterations within an organ and tissues might be reflected in serum or plasma proteomic/peptidic patterns. The aim of the study was to follow the changes in the plasma peptides associated to colorectal cancer progression by mass spectrometry. This study included 27 adenoma, 67 CRC (n = 33 I–II stage and n = 34 III–IV stage), 23 liver metastasis from CRC patients and 34 subjects disease‐free as controls. For plasma peptides analysis, samples purification was performed on the Nanoporous Silica Chips technology followed by matrix‐assisted laser desorption/ionisation‐time of flight analysis. Since the high complexity of the obtained dataset, multivariate statistical analysis, and discriminant pattern recognition were performed for study groups classification. Forty‐four of 88 ionic species were successfully identified as fragments of peptides and proteins physiologically circulating in the blood and belonging to immune and coagulation systems and inflammatory mediators. Many peptides clustered into sets of overlapping sequences with ladder‐like truncation clearly associated to proteolytic processes of both endo‐ and exoproteases activity. Comparing to controls, a different median ion intensity of the group‐type fragments distribution was observed. Moreover, the degradation pattern obtained by proteolytic cleavage was different into study groups. This pattern was specific and characteristic of each group: controls, colon tumour disease (including adenoma and CRC), and liver metastasis, revealing a role as biomarker in early diagnosis and prognosis. Our findings highlighted peculiar changes in protease activity characteristic of CRC progression from pre‐cancer lesion to metastatic disease. J. Cell. Physiol. 231: 915–925, 2016. © 2015 Wiley Periodicals, Inc.
The distribution of response bout lengths and its sensitivity to differential reinforcement
Authors: Brackney Ryan J. , Sanabria Federico
Published: September 2015

Response bouts are clusters of responses that occur in rapid succession and are punctuated by pauses during which the response does not occur. Under variable interval schedules of reinforcement, the number of responses in each bout (the bout length) varies among bouts. This experiment was aimed at determining whether the relative rate of reinforcement influenced the relative frequency of bouts of different lengths. Lever pressing in rats was reinforced under a tandem variable time (VT) 150‐s fixed ratio (FR) X, where X could be 1 or 5 and varied randomly after each reinforcer. Two conditions were included: majority FR1 (mFR1) and majority FR5 (mFR5). In mFR1, 75% of reinforcers had a tandem FR requirement of 1 and 25% had a tandem FR requirement of 5; this distribution was reversed in mFR5. The dynamic bi‐exponential refractory model of response bouts was fitted to the interresponse times (IRTs) in each condition. Model parameter estimates and IRTs were then used to simulate probable distributions of bout lengths. These distributions comprised a mixture of short geometrically‐distributed bout lengths and long negative‐binomially‐distributed bout lengths. Long bouts were significantly longer in the mFR5 condition than in the mFR1 condition. In conjunction with previous data, the present study suggests that the prevalence of long bouts increases with the proportion of reinforcers with FR5 requirement. These results suggest that bouts of different lengths are sensitive to the rate at which they are reinforced.
Synthesis and Antibacterial Activity of Novel Substituted Purine Derivatives
Authors: Wu Wen‐Neng , Gao Man‐Ni , Tu Hong , Ouyang Gui‐Ping
Published: September 2015

A series of novel N‐substituted‐2‐(6‐morpholino‐9H‐purin‐9‐yl)acetamide and 4‐(9‐((5‐substituted‐1,3,4‐oxadiazole/thiadiazole‐2‐yl)methyl)‐9H‐purin‐6‐yl)‐morpholine derivatives were synthesized and evaluated their antibacterial activities against rice bacterial leaf blight and tobacco bacterial wilt caused by Xanthomonas oryzae pv. oryzae (Xoo) and Ralstonia solanacearum (R. solanacearum) via the turbidimeter test in vitro. Antibacterial bioassay indicated that most compounds demonstrated good inhibitory effect against Xoo and R. solanacearum. Especially, compound 6a demonstrated the best inhibitory effect against Xoo with half‐maximal effective concentration (EC50) value of 8.39 μg/mL, which was even better than those of commercial agents Bismerthiazol and Thiodiazole copper. The synthesized purine derivatives containing amide and 1,3,4‐oxadiazole/thiadiazole moieties exhibited excellent antibacterial activities against Xanthomonas oryzae pv. oryzae and R. solanacearum in vitro.