bluuebunny/crossref_metadata_2025 huggingface dataset:
Delineating cellular interactions between ciliates and fish by co‐culturing Tetrahymena thermophila with fish cells
Authors: Pinheiro Marcel D.O. , Bols Niels C.
Published: May 2014

Although several species of Tetrahymena are often described as histophagous and opportunistic pathogens of fish, little is known about ciliate/fish cell interactions, but one approach for studying these is in vitro with cell lines. In this study, T. thermophila, B1975 (wild type) and NP1 (temperature sensitive mutant for phagocytosis) were cultured on monolayers of 3 fish epithelial cell lines, CHSE‐214, RTgill‐W1, and ZEB2J, and the rabbit kidney epithelial cell line, RK‐13. Generally the ciliates flourished, whereas the monolayers died, being completely consumed over several days. The destruction of monolayers required that the ciliates could make contact with the animal cells through swimming, which appeared to dislodge or loosen cells so that they could be phagocytosed. The ciliates internalized into food vacuoles ZEB2J from cell monolayers as well as from cell suspensions. Phagocytosis was essential for monolayer destruction as monolayers remained intact under conditions where phagocytosis was impeded, such as 37°C for NP1 and 4°C for B1975. Monolayers of fish cells supported the proliferation of ciliates. Thus T. thermophila can ‘eat’ animal cells or be histophagous in vitro, with the potential to be histophagous in vivo.
Syngas Production Process Development and Economic Evaluation for Gas‐to‐Liquid Applications
Authors: Maqbool Wahab , Lee Euy Soo
Published: May 2014

The range of syngas composition produced by autothermal reforming of natural gas makes it suitable and in compliance with the gas‐to‐liquid technology for subsequent conversion to synthetic crude oil. A modified and improvised design for this reforming technique is proposed in which oxygen consumption is reduced as compared to the conventional process. Simulative optimization helps in optimal designing of the new process subject to a set of constraints applied to both the processes for uniform and homogeneous comparison. Aspen HYSYS is used for simulation and optimization of the process and the economics are evaluated by an Aspen Process Economic Analyzer.
Determination of the Metastable Zone Width by a Simple Optical Probe
Authors: Chaitanya Koduru K. , Sarkar Debasis
Published: May 2014

The metastable zone width (MSZW) defines an operating boundary for a crystallization process; thus, it is important to determine the MSZW for a given crystallization process. The application of a simple optical probe consisting of a line laser source, a light‐dependent resistor, and a simple processing circuit in the determination of the MSZW of an anti‐solvent crystallization process is presented. The optical probe detects the point of nucleation as a sharp change in output voltage upon the onset of nucleation. The isothermal crystallization of glycine from a glycine/water solution using ethanol as anti‐solvent was used here to assess the performance of the proposed measurement system. The effects of various operating parameters on the MSZW of glycine were also investigated. The kinetic parameters of nucleation were estimated from the data obtained.
New Insights into Glycopeptide Antibiotic Binding to Cell Wall Precursors using SPR and NMR Spectroscopy
Authors: Treviño Juan , Bayón Carlos , Ardá Ana , Marinelli Flavia , Gandolfi Raffaella , Molinari Francesco , Jimenez‐Barbero Jesús , Hernáiz María J.
Published: May 2014

Glycopeptide antibiotics, such as vancomycin and teicoplanin, are used to treat life‐threatening infections caused by multidrug‐resistant Gram‐positive pathogens. They inhibit bacterial cell wall biosynthesis by binding to the D‐Ala‐D‐Ala C‐terminus of peptidoglycan precursors. Vancomycin‐resistant bacteria replace the dipeptide with the D‐Ala‐D‐Lac depsipeptide, thus reducing the binding affinity of the antibiotics with their molecular targets. Herein, studies of the interaction of teicoplanin, teicoplanin‐like A40926, and of their semisynthetic derivatives (mideplanin, MDL63,246, dalbavancin) with peptide analogues of cell‐wall precursors by NMR spectroscopy and surface plasmon resonance (SPR) are reported. NMR spectroscopy revealed the existence of two different complexes in solution, when the different glycopeptides interact with Ac2KdAlaDAlaOH. Despite the NMR experimental conditions, which are different from those employed for the SPR measurements, the NMR spectroscopy results parallel those deduced in the chip with respect to the drastic binding difference existing between the D‐Ala and the D‐Lac terminating analogues, confirming that all these antibiotics share the same primary molecular mechanism of action and resistance. Kinetic analysis of the interaction between the glycopeptide antibiotics and immobilized AcKdAlaDAlaOH by SPR suggest a dimerization process that was not observed by NMR spectroscopy in DMSO solution. Moreover, in SPR, all glycopeptides with a hydrophobic acyl chain present stronger binding with a hydrophobic surface than vancomycin, indicating that additional interactions through the employed surface are involved. In conclusion, SPR provides a tool to differentiate between vancomycin and other glycopeptides, and the calculated binding affinities at the surface seem to be more relevant to in vitro antimicrobial activity than the estimations from NMR spectroscopy analysis.
Analysis of High and Selective Uptake of CO2 in an Oxamide‐Containing {Cu2(OOCR)4}‐Based Metal–Organic Framework
Authors: Alsmail Nada H. , Suyetin Mikhail , Yan Yong , Cabot Rafel , Krap Cristina P. , Lü Jian , Easun Timothy L. , Bichoutskaia Elena , Lewis William , Blake Alexander J. , Schröder Martin
Published: May 2014

The porous framework [Cu2(H2O)2L]⋅4 H2O⋅2 DMA (H4L=oxalylbis(azanediyl)diisophthalic acid; DMA=N,N‐dimethylacetamide), denoted NOTT‐125, is formed by connection of {Cu2(RCOO)4} paddlewheels with the isophthalate linkers in L4−. A single crystal structure determination reveals that NOTT‐125 crystallises in monoclinic unit cell with a=27.9161(6), b=18.6627(4) and c=32.3643(8) Å, β=112.655(3)°, space group P21/c. The structure of this material shows fof topology, which can be viewed as the packing of two types of cages (cage A and cage B) in three‐dimensional space. Cage A is constructed from twelve {Cu2(OOCR)4} paddlewheels and six linkers to form an ellipsoid‐shaped cavity approximately 24.0 Å along its long axis and 9.6 Å across its central diameter. Cage B consists of six {Cu2(OOCR)4} units and twelve linkers and has a spherical diameter of 12.7 Å taking into account the van der Waals radii of the atoms. NOTT‐125 incorporates oxamide functionality within the pore walls, and this, combined with high porosity in desolvated NOTT‐125a, is responsible for excellent CO2 uptake (40.1 wt % at 273 K and 1 bar) and selectivity for CO2 over CH4 or N2. Grand canonical Monte Carlo (GCMC) simulations show excellent agreement with the experimental gas isotherm data, and a computational study of the specific interactions and binding energies of both CO2 and CH4 with the linkers in NOTT‐125 reveals a set of strong interactions between CO2 and the oxamide motif that are not possible with a single amide.
Aromatic Nitrogen Mustard‐Based Prodrugs: Activity, Selectivity, and the Mechanism of DNA Cross‐Linking
Authors: Chen Wenbing , Han Yanyan , Peng Xiaohua
Published: May 2014

Three novel H2O2‐activated aromatic nitrogen mustard prodrugs (6–8) are reported. These compounds contain a DNA alkylating agent connected to a H2O2‐responsive trigger by different electron‐withdrawing linkers so that they are inactive towards DNA but can be triggered by H2O2 to release active species. The activity and selectivity of these compounds towards DNA were investigated by measuring DNA interstrand cross‐link (ICL) formation in the presence or absence of H2O2. An electron‐withdrawing linker unit, such as a quaternary ammonia salt (6), a carboxyamide (7), and a carbonate group (8), is sufficient to deactivate the aromatic nitrogen mustard resulting in less than 1.5 % cross‐linking formation. However, H2O2 can restore the activity of the effectors by converting a withdrawing group to a donating group, therefore increasing the cross‐linking efficiency (>20 %). The stability and reaction sites of the ICL products were determined, which revealed that alkylation induced by 7 and 8 not only occurred at the purine sites but also at the pyrimidine site. For the first time, we isolated and characterized the monomer adducts formed between the canonical nucleosides and the aromatic nitrogen mustard (15) which supported that nitrogen mustards reacted with dG, dA, and dC. The activation mechanism was studied by NMR spectroscopic analysis. An in vitro cytotoxicity assay demonstrated that compound 7 with a carboxyamide linker dramatically inhibited the growth of various cancer cells with a GI50 of less than 1 μM, whereas compound 6 with a charged linker did not show any obvious toxicity in all cell lines tested. These data indicated that a neutral carboxyamide linker is preferable for developing nitrogen mustard prodrugs. Our results showed that 7 is a potent anticancer prodrug that can serve as a model compound for further development. We believe these novel aromatic nitrogen mustards will inspire further and effective applications.
A Rare Example of the Formation of Polystyrene‐Grafted Aliphatic Polyester in One‐Pot by Radical Polymerization
Authors: Shi Yinfeng , Zheng Zhicheng , Agarwal Seema
Published: May 2014

The radical copolymerization of cyclic ester β‐propiolactone (β‐PL) with styrene (St) at 120 °C, with a complete range of monomer ratios, is a rare example of a system providing graft copolymers (PSt‐g‐β‐PL) in one pot. The structure of the resulting β‐PL–St copolymers was proven by using a combination of different characterization techniques, such as 1D and 2D NMR spectroscopy and gel permeation chromatography (GPC), before and after alkaline hydrolysis of the polymers. The number of grafting points increased with an increasing amount of β‐PL in the feed. A significant difference in the reactivity of St and β‐PL and radical chain‐transfer reactions at the polystyrene (PSt) backbone, followed by combination with the active growing poly(β‐PL) chains, led to the formation of graft copolymers by a grafting‐onto mechanism.
gem‐Difluoroolefination of Diaryl Ketones and Enolizable Aldehydes with Difluoromethyl 2‐Pyridyl Sulfone: New Insights into the Julia–Kocienski Reaction
Authors: Gao Bing , Zhao Yanchuan , Hu Mingyou , Ni Chuanfa , Hu Jinbo
Published: May 2014

The direct conversion of diaryl ketones and enolizable aliphatic aldehydes into gem‐difluoroalkenes has been a long‐standing challenge in organofluorine chemistry. Herein, we report efficient strategies to tackle this problem by using difluoromethyl 2‐pyridyl sulfone as a general gem‐difluoroolefination reagent. The gem‐difluoroolefination of diaryl ketones proceeds by acid‐promoted Smiles rearrangement of the carbinol intermediate; the gem‐difluoroolefination is otherwise difficult to achieve through a conventional Julia–Kocienski olefination protocol under basic conditions due to the retro‐aldol type decomposition of the key intermediate. Efficient gem‐difluoroolefination of aliphatic aldehydes was achieved by the use of an amide base generated in situ (from CsF and tris(trimethylsilyl)amine), which diminishes the undesired enolization of aliphatic aldehydes and provides a powerful synthetic method for chemoselective gem‐difluoroolefination of multi‐carbonyl compounds. Our results provide new insights into the mechanistic understanding of the classical Julia–Kocienski reaction.
Magnetic Coupling between Metal Spins through the 7,7,8,8‐Tetracyanoquinodimethane (TCNQ) Dianion
Authors: Saber Mohamed R. , Prosvirin Andrey V. , Abrahams Brendan F. , Elliott Robert W. , Robson Richard , Dunbar Kim R.
Published: May 2014

A family of magnetic metal–organic frameworks, (Ph3PMe)2[M2(TCNQ)3] {M=Fe2+, Co2+, Ni2+ and Zn2+} have been prepared and structurally characterized. The honeycomb‐like “layers” consist of MII ions doubly bridged with dinitrilomethane moieties of two 7,7,8,8‐tetracyanoquinodimethane (TCNQ) dianions which are further connected through phenyl rings to form a 3D dianionic framework [M2TCNQ3]2− with Ph3PMe+ cations filling cavities that run along the c axis. Studies of the magnetic coupling through the TCNQ dianion in these structures revealed that it can promote long‐range magnetic ordering despite the long coupling pathway.
Affinity of Rare Earth Elements to Silico‐Phosphate Phases in the System Al2O3‐CaO‐MgO‐P2O5‐SiO2
Authors: Elwert Tobias , Goldmann Dr.‐Ing Daniel , Schirmer Thomas , Strauß Karl
Published: May 2014

The affinity of Nd and Dy to phosphate containing mineral phases was investigated in this study in an Al2O3‐CaO‐MgO‐P2O5‐SiO2 slag system. The slags originate from pyrometallurgical recycling of NdFeB magnets. Without addition of phosphate, the distribution of Nd and Dy is more or less arbitrary in the silicate matrix. Addition of phosphate leads to the formation of a silico‐phosphate in an early stage of the crystallization process, which scavenges the majority of Nd and Dy. This is due to the strong affinity of these elements to phosphate structures. This phenomenon could be used to produce a rare earth element concentrate by classical mineral beneficiation.
Evaluation of the Separation Efficiency in Metal Melt Filtration with Atomic Force Microscopy
Authors: Heuzeroth Fabian , Fritzsche Jörg , Peuker Urs Alexander
Published: May 2014

Die Filtration von Metallschmelzen ist ein Prozess, um die Qualität von Gussprodukten zu erhöhen. Flüssiges Metall besitzt eine sehr hohe Oberflächenenergie und benetzt deswegen partikuläre Verunreinigungen kaum. Um den Einfluss der Benetzung auf die Filtration zu untersuchen, werden Haftkräfte zwischen Feststoffoberflächen bei unterschiedlichen Benetzungszuständen mit einem Rasterkraftmikroskop gemessen. Die Experimente zeigen, dass die Benetzung die Haftkraft und die erzielte Filtrationsleistung deutlich beeinflusst.
Continuous Electric Sorting in the Recycling Process of Plastics
Authors: Reinsch Edith , Frey Andrea , Albrecht Victoria , Simon Frank , Peuker Urs A.
Published: May 2014

Die Elektrosortierung ist ein kontinuierliches Sortierverfahren, das eine Separation von Kunststoffgemischen im Trockenen und mit relativ geringem Energieaufwand erlaubt. Die triboelektrische Aufladung, die Grundvoraussetzung für eine stoffspezifische Trennung von Teilchen, ist jedoch ein physikalisches Phänomen hoher Komplexität. In diesem Beitrag wird zunächst ein Überblick über den Stand der Forschung zur elektrostatischen Aufladbarkeit von Kunststoffen gegeben. An verschiedenen praxisrelevanten Beispielen wird dann gezeigt, wie Aufladung und Trennung gezielt beeinflusst werden können.
Influence of Calcium Concentration and Dosage Regime on Calcification Mediated Dissolved Inorganic Carbon Capture Efficiency
Authors: Mahanty Biswanath , Kim Subin , Kim Chang Gyun
Published: May 2014

Calcification mediated dissolved inorganic carbon (DIC) sequestration, in the form of insoluble CaCO3, is an environmentally important geochemical process. In this study, the influence of calcium concentration and its dosing regime (single vs. partitioned multiple additions) on DIC capture efficiency (mole of DIC loss per mole of soluble calcium consumed, i.e. ∆DIC/∆Ca2+) and calcification kinetics has been investigated. For this purpose, liquid medium containing 80 mM DIC, generated through microbial ureolysis, was dosed with either varying amount of initial Ca2+ (50–300 mM) or 300 mM Ca2+ equivalent in three equally partitioned doses with the intermittent removal of the precipitate. The analysis of precipitation kinetics revealed a unique precipitation rate constant (0.0836 mM d−1) and a saturation state change rate constant (19.66 ± 1.61 d−1) across all batch experiments. The results suggest that the apparent loss of both soluble Ca2+ and DIC increased along with the initial Ca2+ concentrations, until reaching a plateau. However, ∆DIC/∆Ca2+ continued to decrease, signifying an increased loss of Ca2+ without proportional DIC capture. On the other hand, addition of an equivalent amount of Ca2+ (300 mM) in multiple partitioned dosages not only improved the cumulative DIC removal (from 50.84 mM to 62.27 mM) but also ensured a better ∆DIC/∆Ca2+ ratio. The results could be extended to design an efficient engineered calcification system for carbon sequestration.
Ionic Liquids and Deep Eutectic Mixtures: Sustainable Solvents for Extraction Processes
Authors: Pena‐Pereira Francisco , Namieśnik Jacek
Published: May 2014

In recent years, ionic liquids and deep eutectic mixtures have demonstrated great potential in extraction processes relevant to several scientific and technological activities. This review focuses on the applicability of these sustainable solvents in a variety of extraction techniques, including but not limited to liquid‐ and solid‐phase (micro) extraction, microwave‐assisted extraction, ultrasound‐assisted extraction and pressurized liquid extraction. Selected applications of ionic liquids and deep eutectic mixtures on analytical method development, removal of environmental pollutants, selective isolation, and recovery of target compounds, purification of fuels, and azeotrope breaking are described and discussed.
Harvesting, Storing and Utilising Solar Energy using MoO3: Modulating Structural Distortion through pH Adjustment
Authors: Lou Shi Nee , Ng Yun Hau , Ng Charlene , Scott Jason , Amal Rose
Published: May 2014

Nanostructured molybdenum oxide (α‐MoO3) thin film photoelectrodes were synthesised by anodisation. Upon band gap‐excitation by light illumination, α‐MoO3 is able to store a portion of the excited charges in its layered structure with the simultaneous intercalation of alkali cations. The stored electrons can be discharged from α‐MoO3 for utilisation under dark conditions, and α‐MoO3 is able to recharge itself with successive illuminations to behave as a ‘self‐photo‐rechargeable’ alkali‐ion battery. The alteration of the anodisation pH allowed the crystal structure and oxygen vacancy concentrations of α‐MoO3 to be modulated to achieve (i) a distorted MoO6 octahedra for enhanced charge separation and storage, (ii) a layered structure with a greater exposed (010) crystal face for rich and reversible ion intercalation and (iii) a highly crystalline thin film that suppresses electron–hole pair recombination. Overall, the larger MoO6 octahedral distortion in α‐MoO3 at a higher pH favours charge storage, whereas smaller octahedral distortion at a lower pH leads to anodic photocurrent enhancement.
Periodate‐oxidized ATP modulates macrophage functions during infection with Leishmania amazonensis
Authors: Figliuolo V. R. , Chaves S. P. , Santoro G. F. , Coutinho C. M. L. M. , Meyer‐Fernandes J. R. , Rossi‐Bergmann B. , Coutinho‐Silva R.
Published: May 2014

Previously, we showed that treating macrophages with ATP impairs the intracellular growth of Leishmania amazonensis, and that the P2X7 purinergic receptor is overexpressed during leishmaniasis. In the present study, we directly evaluated the effect of periodate‐oxidized ATP (oATP) on parasite control in Leishmania‐infected macrophages. We found that oATP impaired the attachment/entrance of L. amazonensis promastigotes to C57BL/6 mouse macrophages in a P2X7 receptor‐independent manner, as macrophages from P2X7−/− mice were similarly affected. Although oATP directly inhibited the growth of axenic promastigotes in culture, promoted rapid ultrastructural alterations, and impaired Leishmania internalization by macrophages, it did not affect intracellular parasite multiplication. Upon infection, phagosomal acidification was diminished in oATP‐treated macrophages, accompanied by reduced endosomal proteolysis. Likewise, MHC class II molecules expression and ectoATPase activity was decreased by oATP added to macrophages at the time of parasite infection. These inhibitory effects were not due to a cytotoxic effect, as no additional release of lactate dehydrogenase was detected in culture supernatants. Moreover, the capacity of macrophages to produce nitric oxide and reactive oxygen species was not affected by the presence of oATP during infection. We conclude that oATP directly affects extracellular parasite integrity and macrophage functioning. © 2014 International Society for Advancement of Cytometry
Characterization of the Rx1‐dependent transcriptome during early retinal development
Authors: Giudetti Guido , Giannaccini Martina , Biasci Daniele , Mariotti Sara , Degl'innocenti Andrea , Perrotta Michele , Barsacchi Giuseppina , Andreazzoli Massimiliano
Published: May 2014

Background: The transcription factor Rx1, also known as Rax, controls key properties of retinal precursors including migration behavior, proliferation, and maintenance of multipotency. However, Rx1 effector genes are largely unknown. Results: To identify genes controlled by Rx1 in early retinal precursors, we compared the transcriptome of Xenopus embryos overexpressing Rx1 to that of embryos in which Rx1 was knocked‐down. In particular, we selected 52 genes coherently regulated, i.e., actived in Rx1 gain of function and repressed in Rx1 loss of function experiments, or vice versa. RT‐qPCR and in situ hybridization confirmed the trend of regulation predicted by microarray data for the selected genes. Most of the genes upregulated by Rx1 are coexpressed with this transcription factor, while downregulated genes are either not expressed or expressed at very low levels in the early developing retina. Putative direct Rx1 target genes, activated by GR‐Rx1 in the absence of protein synthesis, include Ephrin B1 and Sh2d3c, an interactor of ephrinB1 receptor, which represent candidate novel effectors for the migration promoting activity of Rx1. Conclusions: This study identifies previously undescribed Rx1 regulated genes mainly involved in transcription regulation, cell migration/adhesion, and cell proliferation that contribute to delineate the molecular mechanisms underlying Rx1 activities. Developmental Dynamics 243:1352–1361, 2014. © 2014 Wiley Periodicals, Inc.
Task Estimation Using Latent Semantic Analysis of Visual Scenes and Spoken Words
Authors: Kimura Masashi , Sawada Shinta , Iribe Yurie , Katsurada Kouichi , Nitta Tsuneo
Published: May 2014

In this paper, we propose a task estimation method based on multiple subspaces extracted from multimodal information of image objects in visual scenes and spoken words in dialogue appearing in the same task. The multiple subspaces are obtained by using latent semantic analysis (LSA). In the proposed method, a task vector composed of spoken words and the frequencies of image‐object appearances are extracted first, and then similarities among the input task vector and reference subspaces of different tasks are compared. Experiments are conducted on the identification of game tasks. The experimental results show that the proposed method with multimodal information outperforms the method in which only the single modality of image or spoken dialogue is applied. The proposed method achieves accurate performance even if less spoken dialogue is applied.
Spatial heterogeneity of fine root biomass and soil carbon in a California oak savanna illuminates plant functional strategy across periods of high and low resource supply
Authors: Koteen Laura E. , Raz‐Yaseef Naama , Baldocchi Dennis D.
Published: May 2014

We sampled isolated trees and tree clusters from a blue oak, Quercus douglasii, savanna to determine the spatial heterogeneity of fine root biomass and soil carbon across the landscape as a function of tree size and configuration. We aimed to understand how fine root structure enables sustained ecosystem metabolism through a summer of limited moisture and high heat and facilitates resource acquisition during the short period of high resource supply. An additional goal was to provide a basis for upscaling root biomass and soil carbon to the landscape scale. We sampled trees of different size and tree clusters via a stratified sampling scheme that accounted for spatial heterogeneity in root biomass and soil carbon with lateral distance from the tree bole, or cluster centre, and soil depth. We upscaled these estimates using site‐specific information from a lidar survey. We found that fine roots and soil carbon are spatially heterogeneous in their landscape distribution and greatly increase with tree size. We also found that Q. douglasii possesses a dimorphic fine root architecture, uniquely suited to the region's climatic constraints and exhibits morphological plasticity among trees of different size and physical setting. Copyright © 2014 John Wiley & Sons, Ltd.
Dendritic cell development requires histone deacetylase activity
Authors: Chauvistré Heike , Küstermann Caroline , Rehage Nina , Klisch Theresa , Mitzka Saskia , Felker Piritta , Rose‐John Stefan , Zenke Martin , Seré Kristin M.
Published: May 2014

DCs develop from multipotent progenitors (MPPs), which commit into DC‐restricted common dendritic cell progenitors (CDPs). CDPs further differentiate into classical DCs (cDCs) and plasmacytoid DCs (pDCs). Here, we studied the impact of histone acetylation on DC development in C57BL/6 mice by interfering with histone acetylation and deacetylation, employing histone deacetylase (HDAC) inhibitors. We observed that commitment of MPPs into CDPs was attenuated by HDAC inhibition and that pDC development was specifically blocked. Gene expression profiling revealed that HDAC inhibition prevents establishment of a DC‐specific gene expression repertoire. Importantly, protein levels of the core DC transcription factor PU.1 were reduced in HDAC inhibitor‐treated cells and consequently PU.1 recruitment at PU.1 target genes Fms‐like tyrosine kinase 3 (Flt3), interferon regulatory factor 8 (IRF8), and PU.1 itself was impaired. Thus, our results demonstrate that attenuation of PU.1 expression by HDAC inhibition causes reduced expression of key DC regulators, which results in attenuation of DC development. We propose that chromatin modifiers, such as HDACs, are required for establishing a DC gene network, where Flt3/STAT3 signaling drives PU.1 and IRF8 expression and DC development. Taken together, our study identifies HDACs as critical regulators of DC lineage commitment and development.
Oxysterol‐EBI2 signaling in immune regulation and viral infection
Authors: Daugvilaite Viktorija , Arfelt Kristine Niss , Benned‐Jensen Tau , Sailer Andreas W. , Rosenkilde Mette M.
Published: May 2014

The seven transmembrane G protein‐coupled receptor Epstein‐Barr virus (EBV) induced gene 2 (EBI2; also known as GPR183) was identified in 1993 on the basis of its substantial upregulation in EBV‐infected cells. It is primarily expressed in lymphoid cells; most abundantly in B cells. EBI2 is central for the positioning of B cells within the lymphoid organs, a process that is regulated in part by a chemotactic gradient formed by the endogenous lipid agonists, and in part by a fine‐tuned regulation of EBI2 cell surface expression. The most potent endogenous EBI2 agonist is 7α, 25‐dihydroxyxcholesterol (7α,25‐OHC), yet many structurally related oxysterols can bind to an EBI2 pocket that is defined by the upper parts of the transmembrane helices and extracellular receptor regions. EBI2 signals via Gαi, as well as via G protein‐independent pathways like β‐arrestin recruitment. The concerted action of these pathways leads to cell migration. By genetically interfering with its up‐ and downregulation, EBI2 was also recently shown to induce cell proliferation, an action that could be inhibited by small molecule antagonists. Here, we focus on the oxysterol–EBI2 axis in immune control, including its role in the EBV life cycle. We also summarize the structural and functional properties of EBI2 interaction with oxysterol agonists and small molecule antagonists and discuss EBI2 as therapeutic target for diseases of the immune system.
Effective Use of Mesoporous Silica Filler: Comparative Study on Thermal Stability and Transparency of Silicone Rubbers Loaded with Various Kinds of Silica Particles
Authors: Suzuki Norihiro , Kamachi Yuichiro , Takai Kimiko , Kiba Shosuke , Sakka Yoshio , Miyamoto Nobuyoshi , Yamauchi Yusuke
Published: May 2014

Four types of silica fillers (nonporous silica particles, mesoporous silica particles, silica gels with micropores, and fumed silica particles) have been used as inorganic filler materials for silicone rubber. To determine their effectiveness as filler materials, a systematic study on the thermal strength and transparency of the obtained silica/silicone composites was conducted. The mesoporous silica/silicone composite shows the lowest thermal expansion and higher transparency than the other composites. The thermal strength and transparency of silica gel/silicone composite is quite similar to those of nonporous silica/silicone composite. Fumed silica/silicone composite is highly transparent (indeed, its transparency is the same as pristine silicone), but the thermal strength is at the same level as nonporous silica/silicone composite. These results clarify that mesoporous silica particles are the most promising filler materials for silicone rubber.
Directional Self‐Assembly of Exfoliated Layered Europium Hydroxide Nanosheets and Na9EuW10O36·32H2O for Application in Desulfurization
Authors: Wang Xiaoting , Chen Wei , Song Yu‐Fei
Published: May 2014

The directional self‐assembly of exfoliated layered europium hydroxide (LEuH) nanosheets and europium‐containing heteropolytungstate anions has been achieved by mixing an LEuH colloidal solution and a Na9EuW10O36·32H2O (EuW10) solution at room temperature leading to the formation of a new inorganic/inorganic hybrid material, Eu2(OH)5(EuW10O36)0.11·5.5H2O (LEuH‐EuW10). The use of LEuH‐EuW10 in extractive catalytic oxidative desulfurization (ECODS) showed that highly efficient and selective deep desulfurization can be achieved in only 15 min under mild conditions. A maximum turnover number (TON) of around 1600 has been achieved. In addition, the catalyst can be recycled and reused at least 10 times with only a slight loss of catalytic efficiency.
Exploring the Building‐Block Potential of Readily Accessible Chiral [Zn(salen)] Complexes
Authors: Martin Eddy , Martínez Belmonte Marta , Escudero‐Adán Eduardo C. , Kleij Arjan W.
Published: May 2014

The synthesis and full characterization of a series of chiral [Zn(salen)] [salen = N,N′‐bis(salicylidene)ethylenediamine dianion] complexes comprising a 1,2‐diphenylethane backbone is reported. The preparation method reported here simplifies the previously communicated methodology for these types of Zn complexes that utilized air‐sensitive ZnEt2 (or similar) as the metalating reagent. X‐ray molecular structures are also reported for representative examples of this family of [Zn(salen)] complexes. A wide range of functionality is shown to be accessible by means of the present route, thereby amplifying the potential use of these (Lewis acidic) Zn complexes as molecular building blocks. Examples in this work include the formation of supramolecular assemblies having built‐in bifunctionality using versatile Zn–N and Zn–O coordination motifs as guiding tools.
Oxidative stability of lipids from hepatopancreas of Pacific white shrimp (Litopenaeus vannamei) as affected by essential oils incorporation
Authors: Takeungwongtrakul Sirima , Benjakul Soottawat
Published: May 2014

Oxidative stability of lipids from hepatopancreas of Pacific white shrimp (Litopenaeus vannamei) added with different essential oils at 200 ppm during 10 days of storage was studied. With increasing storage time, the progressive formation of hydroperoxide was found in all samples as evidenced by the increases in peroxide values (PV) (p<0.05). Amongst all essential oils tested, lemon essential oil exhibited the highest preventive effect against oxidation, followed by plai and basil essential oils, respectively. The increases in thiobarbituric acid reactive substances (TBARS) and ρ‐anisidine value (AnV) of lipids were noticeable when storage time increased (p<0.05). The increases in TBARS and AnV were retarded in the presence of essential oils. Nevertheless, the effectiveness for prevention of lipid oxidation of all three essential oils was slightly lower than α‐tocopherol when used at the same level. The formation of volatile compounds and rancid odour of samples were lowered when being incorporated with essential oils. Based on sensory evaluation, lipid containing lemon essential oil had a similar rancid odour to that added with α‐tocopherol. Thus, essential oils could be used as natural antioxidants to retard lipid oxidation and rancidity of lipids from hepatopancreas during extended storage.

Practical applications: Shrimp hepatopancreas, a byproduct from shrimp processing industries, is an important source of lipids and astaxanthins, which are susceptible to oxidation. Their changes are associated with development of off‐odour and loss of nutritive value. Therefore, the uses of natural antioxidants, especially essential oils, can be a potential means to retard lipid oxidation and rancidity of shrimp oil during extended storage.

Essential oils could be used as natural antioxidants to retard lipid oxidation and rancidity of lipids from hepatopancreas during extended storage.
An Approach to the Selenobromination of Aryl(thienyl)alkynes: Access to 3‐Bromobenzo[b]selenophenes and Selenophenothiophenes
Authors: Paegle Edgars , Belyakov Sergey , Arsenyan Pavel
Published: May 2014

A novel approach for the cyclization of arylalkynes with selenium(IV) bromide prepared in situ has been elaborated. The use of an alkene additive as a bromine scavenger provides a convenient synthetic pathway for the synthesis of a wide variety of 3‐bromobenzo[b]selenophenes. Reactions can be performed open to air without the use of moisture‐sensitive reagents, anhydrous solvents, or an inert atmosphere. Selenobromination of ethynylthiophenes has been applied for the preparation of selenopheno[3,2‐b]‐ and selenopheno[2,3‐b]thiophenes. The molecular structures of representative derivatives have been confirmed by X‐ray crystallographic analysis.
On the Ion‐Pair Recognition and Indication Features of a Fluorescent Heteroditopic Host Based on a BODIPY Core
Authors: Gotor Raúl , Costero Ana M. , Gil Salvador , Gaviña Pablo , Rurack Knut
Published: May 2014

A fluorescent heteroditopic host for ion pairs and zwitterionic species has been synthesized. Its affinity towards a series of anions, cations and ion pairs in acetonitrile has been assessed, and the spectroscopic response has been evaluated. Solid–liquid extraction experiments of inorganic salts, α‐amino acids and γ‐aminobutyric acid (GABA) into acetonitrile solutions were performed, and the resulting complexes were analyzed by UV/Vis absorption, fluorescence and 1H NMR spectroscopy. The discrimination patterns observed have been rationalized in terms of the molecular topologies of the host and guests.
Self‐reported recurrent pain and medicine use behaviours among 15‐year olds: Results from the international study
Authors: Gobina I. , Villberg J. , Villerusa A. , Välimaa R. , Tynjälä J. , Ottova‐Jordan V. , Ravens‐Sieberer U. , Levin K. , Cavallo F. , Borraccino A. , Sigmund E. , Andersen A. , Holstein B.E.
Published: May 2014

Background

There is considerable variation in adolescent pain prevalence across epidemiological studies, with limited information on pain‐related behaviours among adolescents, including medicine use. The aims of this study were (1) to examine the prevalence of recurrent pain among 15‐year‐old adolescents internationally; (2) to investigate the association between recurrent pain and medicine use behaviours among boys and girls; and (3) to evaluate the consistency of these associations across countries.

Methods

The World Health Organization (WHO) collaborative international Health Behaviour in School‐aged Children 2009/2010 study collects data about self‐reported aches and medicine use from 36,762 15‐year‐old adolescents from 22 countries/regions in Europe and the United States. Multi‐level multivariate logistic regression, stratified by gender, was used to analyse the association between recurrent pain and medicine use for headache, stomachache, nervousness and difficulties in getting to sleep.

Results

More than 30% of adolescents reported recurrent headache, almost 30% recurrent backache and approximately 20% recurrent stomachache. Although pain prevalence and medicine use for aches were much higher for girls, the association between pain and medicine use was similarly strong for both genders. Adolescents with recurrent pain are more likely to use medicines also for non‐corresponding pain, nervousness and difficulties in getting to sleep. The association between recurrent pain and medicine use was consistent across countries despite large‐country differences in the prevalence of recurrent pain and medicine use.

Conclusions

Recurrent pain in adolescence is common cross‐nationally. Adolescents with recurrent pain are more likely to use medicine in general. Recurrent pain and medicine use should be addressed in adolescent health policies.
Paper‐Based Electrochemical Biosensors: From Test Strips to Paper‐Based Microfluidics
Authors: Liu Bingwen , Du Dan , Hua Xin , Yu Xiao‐Ying , Lin Yuehe
Published: May 2014

Papers based biosensors such as lateral flow test strips and paper‐based microfluidic devices are inexpensive, rapid, flexible, and easy‐to‐use analytical tools for point‐of‐care diagnosis. An apparent trend in their detection is to interpret sensing results from qualitative assessment to quantitative determination. Electrochemical (EC) detection plays an important role in quantifying test results. This review focuses on paper‐based biosensors with EC detection. The first part provides detailed examples in lateral flow test strips while the second part gives an overview of paper microfluidics. The outlook and recommendation of future directions of papers based EC biosensors are discussed in the end.
A Bayesian hierarchical model for forecasting intermountain snow dynamics
Authors: Odei James B. , Symanzik Jürgen , Hooten Mevin B.
Published: May 2014

Because of a continual increase in the demand for water as well as an ongoing regional drought, there is an imminent need to monitor and forecast water resources in the Western United States. In particular, water resources in the Intermountain West rely heavily on snow water storage. Thus, the need to improve seasonal forecasts of snowpack and considering new techniques would allow water resources to be more effectively managed throughout the entire water‐year. Many available models used in forecasting snow water equivalent (SWE) measurements require delicate calibrations. In contrast to the physical SWE models most commonly used for forecasting, we offer a statistical model. We present a data‐based statistical model that characterizes seasonal SWE in terms of a nested time series, with the large scale focusing on the inter‐annual periodicity of dominant signals and the small scale accommodating seasonal noise and autocorrelation. This model provides a framework for independently estimating mainly the temporal dynamics of SWE for the various snow telemetry sites. We use snow telemetry data from 10 stations in Utah over 34 water‐years to implement and validate this model. Copyright © 2014 John Wiley & Sons, Ltd.
Supporting brace sizing in structures with added linear viscous fluid dampers: A filter design solution
Authors: Londoño Julián M. , Wagg David J. , Neild Simon A.
Published: May 2014

Viscous fluid dampers have proved to be effective in suppressing unwanted vibrations in a range of engineering structures. When dampers are fitted in a structure, a brace is typically used to attach them to the main structure. The stiffness of this brace can significantly alter the effectiveness of the damper, and in structures with multiple dampers, this can be a complex scenario to model. In this paper, we demonstrate that the effects of the brace compliance on the damper performance can be modelled by way of a first‐order filter. We use this result to formulate a procedure that calculates the stiffness required by the supporting brace to provide a specified effectiveness of the damping action. The proposed procedure assumes that viscous dampers have been sized in a previous design step based on any optimal methodology in which, as is usually the case, the presence of supporting braces and their dynamic effects were neglected. Firstly considering a one degree‐of‐freedom system, we show that the proposed method ensures a desired level of damper efficiency for all frequencies within a selected bandwidth. Then the analysis is extended to the case of multi‐degree‐of‐freedom systems to show that the design criteria can be applied in a straightforward and successful manner to more complex structures. © 2014 The Authors. Earthquake Engineering & Structural Dynamics published by John Wiley & Sons Ltd.
Nonlinear eigenvalue problems: a challenge for modern eigenvalue methods
Authors: Mehrmann Volker , Voss Heinrich
Published: May 2014

We discuss the state of the art in numerical solution methods for large scale polynomial or rational eigenvalue problems. We present the currently available solution methods such as the Jacobi‐Davidson, Arnoldi or the rational Krylov method and analyze their properties. We briefly introduce a new linearization technique and demonstrate how it can be used to improve structure preservation and with this the accuracy and efficiency of linearization based methods. We present several recent applications where structured and unstructured nonlinear eigenvalue problems arise and some numerical results. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Topics in the numerical linear algebra of Toeplitz and Hankel matrices
Authors: Böttcher Albrecht , Rost Karla
Published: May 2014

This is an introduction to some aspects of the numerical linear algebra of large matrices with Toeplitz, Hankel, and Toeplitz‐plus‐Hankel structures. The concrete topics we have selected are determined by our preferences and by work we have participated in. We give an introduction to the symbol calculus, we touch exact and asymptotic formulas for inverses, including the notion of a Bezoutian, we consider eigenvalues, pseudospectra, eigenvectors, and condition numbers, and we embark on the fast solution of Toeplitz systems. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
New hybridization techniques
Authors: Cockburn Bernardo , Gopalakrishnan Jayadeep
Published: May 2014

In this paper we present an overview of some new hybridization techniques for linear secondorder elliptic problems. We begin by introducing the hybridization technique through a simple one dimensional example. We then introduce a new point of view with which previously unsuspected applications of hybridization have become possible. Presentation of these applications is the main objective of this review. One such application is in comparing and establishing connections between mixed methods. Next we show how hybridization makes possible the construction of high order variable degree mixed methods. We develop a new error analysis for mixed methods making essential use of hybridization resulting in new error estimates for our new as well as old methods. Finally, we show that via hybridization one can solve the long standing research problem of computing numerical approximations to Stokes flow that are exactly divergence free. We show this for a discontinuous Galerkin method and then for a classical mixed method. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Geology, isotope geochemistry, and ore genesis of the Yindonggou Ag–Au(–Pb–Zn) deposit, Hubei Province, China
Authors: Yue Su‐Wei , Deng Xiao‐Hua , Bagas Leon
Published: May 2014

The Yindonggou Ag–Au(–Pb–Zn) deposit is hosted by metamorphosed volcanic rocks of the ca. 740–760 Ma Wudangshan Group in the Proterozoic Wudang Block of the southern part of the Qinling Orogen, central China. The deposit consists of a series of mineralized quartz veins located in the Yindongyan Anticline. Based on the mineral assemblages and cross‐cutting relationships of quartz veins, the deposit can be divided into: (1) early fine‐grained quartz–sphalerite–galena veins; (2) fine‐grained quartz–silver–gold veins containing minor amounts of pyrite; (3) coarse‐grained quartz veins with minor amounts of galena, sphalerite, and chalcopyrite; and (4) late ankerite–quartz veins. Most of the Pb–Zn mineralization formed during the early (Stage 1) veins followed by the deposition of Ag–Au mineralization in the Stage 2 veins. The δ18O value for the ore‐forming fluids decreases from 6.6–9.4‰ in the Stage 1 veins through 3.6–4.9‰ in the Stage 2 veins to −1.2‰ to 0.4‰ in the Stage 3 veins (the δ18O values could not be determined for the Stage 4 veins). Furthermore, the δD values are −74‰ for the Stage 1 veins, −95‰ to −56 ‰ for the Stage 2 veins, and −48‰ to −73‰ for the Stage 3 veins. The δ13C values for ankerite in the Stage 4 veins are between −2.9‰ and −1.1‰. The δD vs. δ18OH2O plot for these values indicates that there was a shift from metamorphic fluids during the formation of the early veins to meteoric fluids during the formation of the later veins at the deposit. The H–O–C isotope systematics also indicate that the ore fluids forming the deposit were probably initially sourced from metamorphic dehydration of volcanic‐carbonate rocks in the ca. 740–760 Ma Wudangshan Group and with time gradually mixed with meteoric water by Stage 4. The δ34S values for sulphides from the deposit range from −0.9‰ to 7.1‰ in the Stage 1 veins, 3.8‰ to 5.0‰ in the Stage 2 veins, and 2.4‰ to 11.3‰ in the wallrocks. Sulphides from the mineralized Stage 1 veins yield 206Pb/204Pb ratios of 16.44–16.6, 207Pb/204Pb ratios of 15.25–15.5, and 208Pb/204Pb ratios of 36.4–36.98. Five pyrite samples from the Stage 2 veins yield 206Pb/204Pb ratios of 16.475–16.529, 207Pb/204Pb ratios of 15.346–15.395, and 208Pb/204Pb ratios of 36.49–36.616. Both the S and Pb isotope ratios are between the ratios for units in the Wudangshan Group and mantle but differ from other lithological units in the Wudang Block, which suggest that the mineralized fluids interacted with both the Wudangshan Group and deep‐seated sources. Thus, we suggest that the original ore‐forming fluids are metamorphic in origin, and the metal deposition resulted from fluid mixing. From the characteristics observed, the Yindonggou Ag–Au(–Pb–Zn) deposit can be classified as an orogenic‐type deposit generated during the Triassic Qinling Orogeny resulting from northward oceanic plate subduction along the Mian‐Lue Suture. Copyright © 2014 John Wiley & Sons, Ltd.