bluuebunny/crossref_metadata_2025 huggingface dataset:
Uncertainties in atmospheric chemistry modelling due to convection parameterisations and subsequent scavenging
Authors: Tost H. , Lawrence M. G. , Brühl C. , Jöckel P. ,   The GABRIEL Team,   The SCOUT-O3-DARWIN/ACTIVE Team
Published: April 2010

Abstract. Moist convection in global modelling contributes significantly to the transport of energy, momentum, water and trace gases and aerosols within the troposphere. Since convective clouds are on a scale too small to be resolved in a global model their effects have to be parameterised. However, the whole process of moist convection and especially its parameterisations are associated with uncertainties. In contrast to previous studies on the impact of convection on trace gases, which had commonly neglected the convective transport for some or all compounds, we investigate this issue by examining simulations with five different convection schemes. This permits an uncertainty analysis due to the process formulation, without the inconsistencies inherent in entirely neglecting deep convection or convective tracer transport for one or more tracers. Both the simulated mass fluxes and tracer distributions are analysed. Investigating the distributions of compounds with different characteristics, e.g., lifetime, chemical reactivity, solubility and source distributions, some differences can be attributed directly to the transport of these compounds, whereas others are more related to indirect effects, such as the transport of precursors, chemical reactivity in certain regions, and sink processes. The model simulation data are compared with the average regional profiles of several measurement campaigns, and in detail with two campaigns in fall and winter 2005 in Suriname and Australia, respectively. The shorter-lived a compound is, the larger the differences and consequently the uncertainty due to the convection parameterisation are, as long as it is not completely controlled by local production that is independent of convection and its impacts (e.g. water vapour changes). Whereas for long-lived compounds like CO or O3 the mean differences between the simulations are less than 25%), differences for short-lived compounds reach up to ±100% with different convection schemes. A rating of an overall "best" performing scheme is difficult, since the optimal performance depends on the region and compound.
Biogenic nitrogen oxide emissions from soils – impact on NOx and ozone over West Africa during AMMA (African Monsoon Multidisciplinary Experiment): modelling study
Authors: Delon C. , Reeves C. E. , Stewart D. J. , Serça D. , Dupont R. , Mari C. , Chaboureau J.-P. , Tulet P.
Published: April 2010

Abstract. Nitrogen oxide biogenic emissions from soils are driven by soil and environmental parameters. The relationship between these parameters and NO fluxes is highly non linear. A new algorithm, based on a neural network calculation, is used to reproduce the NO biogenic emissions linked to precipitations in the Sahel on the 6 August 2006 during the AMMA campaign. This algorithm has been coupled in the surface scheme of a coupled chemistry dynamics model (MesoNH Chemistry) to estimate the impact of the NO emissions on NOx and O3 formation in the lower troposphere for this particular episode. Four different simulations on the same domain and at the same period are compared: one with anthropogenic emissions only, one with soil NO emissions from a static inventory, at low time and space resolution, one with NO emissions from neural network, and one with NO from neural network plus lightning NOx. The influence of NOx from lightning is limited to the upper troposphere. The NO emission from soils calculated with neural network responds to changes in soil moisture giving enhanced emissions over the wetted soil, as observed by aircraft measurements after the passing of a convective system. The subsequent enhancement of NOx and ozone is limited to the lowest layers of the atmosphere in modelling, whereas measurements show higher concentrations above 1000 m. The neural network algorithm, applied in the Sahel region for one particular day of the wet season, allows an immediate response of fluxes to environmental parameters, unlike static emission inventories. Stewart et al (2008) is a companion paper to this one which looks at NOx and ozone concentrations in the boundary layer as measured on a research aircraft, examines how they vary with respect to the soil moisture, as indicated by surface temperature anomalies, and deduces NOx fluxes. In this current paper the model-derived results are compared to the observations and calculated fluxes presented by Stewart et al (2008).
Hexahydropyrrolo[2,3‐b]indoles: A New Class of Structurally Rigid Tricyclic Skeleton for Oxazaborolidine‐Catalyzed Asymmetric Borane Reduction
Authors: Xiao Jian , Wong Zhen Zhou , Lu Yun Peng , Loh Teck Peng
Published: April 2010

A new class of structurally rigid tricyclic chiral ligands based on the hexahydropyrrolo[2,3‐b]indole skeleton has been rationally designed and the catalytic abilities in asymmetric catalysis have been shown in the enantioselective borane reduction of prochiral ketones to afford the chiral alcohols in excellent yields and high enantioselectivities (up to 97% ee).
Novel N‐ethyl‐2‐styrylquinolinum iodides as sensitizers in photoinitiated free radical polymerization of trimethylolopropane triacrylate (TMPTA), part 3
Authors: Kabatc Janina , Pączkowski Jerzy
Published: April 2010

Three‐component systems, which contain a light‐absorbing species (dye), an electron donor (n‐butyltriphenylborate salt), and a third component (N‐alkoxypyridinum salt or 1,3,5‐triazine derivative), have emerged as efficient, visible‐light sensitive photoinitiators of free radical polymerization. It was found that three‐component systems are more efficient than their two‐component counterparts. Kinetic studies based on microcalorimetry revealed a significant increase in polymerization rate with increasing concentration of N‐alkoxypyridinum salt. Such results were not obtained for photoinitiating systems possessing 1,3,5‐triazine derivative as a second coinitiator. Based on the experimental results we concluded that the primary photochemical reaction involves electron transfer from the borate anion to the excited dye followed by the reaction of resulting dye‐based radical with second coinitiator that regenerates the original dye and simultaneously produces the alkoxy radical or triazynyl radical which could start the polymerization chain reaction. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Electrochemical polymerization of p‐terphenyl in mixed electrolyte of boron trifluoride diethyl etherate and CH2Cl2
Authors: Zhou Weiqiang , Xu Jingkun , Du Yukou , Yang Ping
Published: April 2010

High quality poly(p‐phenylene) (PPP) film with conductivity of 0.015 S cm−1 was synthesized electrochemically by direct anodic oxidation of p‐terphenyl (PP) oligomers in boron trifluoride diethyl etherate (BFEE) containing 37.5% CH2Cl2 (v/v). The oxidation onset potential of PP in this medium was measured to be only 1.23 V vs. saturated calomel electrode (SCE), which was lower than that determined in CH2Cl2 + 0.1 mol L−1 Bu4NBF4 (1.87 V vs. SCE). As‐formed PPP films showed good electrochemical behavior, good electrochromic property and good thermal stability. The structures and morphology of doped and dedoped PPP were investigated by UV‐vis, FTIR, and Scanning electron micrographs. The infrared spectroscopic measurements for the estimation of chain lengths revealed that PPP was composed of about 10 phenyl rings. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Synthesis and photopolymerization of phosphonic acid monomers for applications in compomer materials
Authors: Catel Yohann , Le Pluart Loïc , Madec Pierre‐Jean , Pham Thi‐Nhàn
Published: April 2010

Novel methacrylate monomers bearing phosphonic acid groups 1 and 2 as well as new sulfur methacrylates 9 and 10 have been prepared in good yields from thiophenol. They have been fully characterized by 1H‐NMR, 13C‐NMR, 31P‐NMR, and HRMS. Their copolymerization with a bis‐GMA : TEGDMA (1 : 1) blend has been investigated with photodifferential scanning calorimetry at 50°C with camphorquinone as a photoinitiator and ethyl 4‐(dimethylamino)benzoate (EDAB) as a coinitiator. The higher the content of acidic monomer 1 or 2 incorporated in the bis‐GMA : TEGDMA (1 : 1) blend, the lower the mixtures reactivity. The phosphonic acid group has been proved to be responsible for this drop of reactivity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Aqueous chloramine diffusion into elastomers
Authors: Nagisetty Raja M. , Rockaway Thomas D. , Willing Gerold A.
Published: April 2010

Aqueous chloramine diffusion into styrene butadiene rubber (SBR) and natural rubber was analyzed using approximate analytical and numerical solutions of Fick's second law of diffusion to develop long‐term mass intake prediction curves. Diffusion coefficients were calculated for 1 mg/L chloramine concentration at three temperatures (23, 45, and 70°C) and also for 23°C at three chloramine concentrations (1, 30, and 60 mg/L). The reasonableness of using increased temperature and/or chloramine concentration to accelerate the diffusion process to obtain long‐term information was discussed. For 1 mg/L chloramine concentration, the activation energy for the diffusion of chloramines into SBR and natural rubber were computed to be 51.13 and 77.29 kJ/mol, respectively. Also, concentration profiles were developed to understand the extent of penetration through the elastomer thickness over time and temperature. Considering the reports of elastomeric compound failure in chloramine disinfectant water distribution systems because of swelling, this study will be helpful in understanding the performance of the elastomeric compounds in the system. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
A library of thiol‐terminated methacrylate telomers prepared by photoinitiated iniferter mediated polymerization for use in modifications of chromatographic surfaces by the “grafting to” approach
Authors: Nordborg Anna , Irgum Knut
Published: April 2010

A library of thiol‐terminated methacrylate telomers aimed for use in surface modifications of chromatographic support materials has been prepared by iniferter mediated polymerization, using isopropylxanthic disulfide as a photoiniferter. The telomers range from hydrophobic to hydrophilic and were prepared in different lengths, with the length being adjusted by the ratio of monomer to iniferter used in the polymerization mixture. The telomers were characterized by size‐exclusion chromatography and MALDI‐TOF‐MS. In initial surface characterization experiments, the prepared telomers were attached to the inner surface of fused silica capillaries by radical initiated addition to vinyl groups, and the electro‐osmotic flow (EOF) in the prepared capillaries was determined in a capillary electrophoresis set‐up. The EOF measurements verified surface grafting. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation of poly(lactic acid)/poly(methyl methacrylate)/silicon dioxide degradable hybrid electrolytes
Authors: Wang Hualin , Shu Liping , Jiang Shaotong
Published: April 2010

On the basis of sol–gel methodology, a novel degradable hybrid electrolyte, poly(lactic acid) (PLA)/poly(methyl methacrylate) (PMMA)/silicon dioxide (SiO2) hybrid electrolyte, was prepared from PLA, methyl methacrylate, and tetraethoxylsilicon with 3‐methacryloxypropyl trimethoxysilane as a coupling agent. As observed from Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy spectra, the PLA, PMMA, and silica units were linked by covalent bonds through the coupling agent in a hybrid network. Differential scanning calorimetry results show that the heat‐resistance properties of the hybrid electrolyte improved with increasing SiO2 content. The hybrid electrolyte was shown to be amorphous by the X‐ray diffraction results. From study of ionic conductivity by alternating‐current impedance, the ionic conductivity of the PLA/PMMA/SiO2 hybrid electrolyte increased with increasing silica content, reached a maximum value of 2.42 × 10−4 S/cm at 2 wt % SiO2, and then decreased. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation and characterization of crosslinked poly(methylmethacrylate‐acrylic acid sodium salt)‐modified bone cement
Authors: Nien Yu‐Hsun , Chen Shao‐Heng , Chen Jian‐Wen
Published: April 2010

Bone cement is used as load‐distributing filler between the prosthesis and the bone as well as a method to anchor prosthesis in orthopedic implants. In this study, crosslinked poly(methylmethacrylate‐acrylic acid sodium salt), denoted as poly(MMA‐AAS‐AMA), was applied to bone cement. Allylmethacrylate (AMA) was used as a crosslinking agent. It was demonstrated by FTIR that the wavenumbers of the asymmetrical and symmetrical stretching vibrations for carboxylate anion of poly(MMA‐AAS‐AMA) were 1586 and 1407 cm−1, respectively. The poly(MMA‐AAS‐AMA)‐modified bone cement was prepared and characterized using tensile and compressive test. An excess of poly(MMA‐AAS‐AMA) in bone cement caused poor mechanical properties of the modified bone cement, because poly(MMA‐AAS‐AMA) absorbed water. In dynamic mechanical analysis, the excessive content of poly(MMA‐AAS‐AMA) lowered the stiffness of the modified bone cement, because of water existed in poly(MMA‐AAS‐AMA). The glass transition temperature of the bone cement shifted to higher temperature at higher frequency because of viscoelasticity. Based on swelling measurement, the modified bone cement was able to swell in controlled manner, and the swelling rate of the modified bone cement was improved. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Color improvment of C9hydrocarbon resin by hydrogenation over 2% Pd/γ‐alumina catalyst: Effect of degree of aromatic rings hydrogenation
Authors: Sae‐Ma Nikom , Praserthdam Piyasan , Panpranot Joongjai , Chaemchuen Somboon , Dokjamp Siraprpha , Suriye Kongkiat , Rempel Garry L.
Published: April 2010

Color improvement of commercial C9hydrocarbon resin (c‐C9HR) and prepared C9hydrocarbon resin (p‐C9HR) has been investigated under various hydrogenation conditions over 2% Pd/γ‐alumina catalysts. The degrees of aromatic rings hydrogenation (DHs) and molecular structure of resin were determined from nuclear magnetic resonance of1H and13C (1H‐NMR and13C‐NMR) and Fourier transform infrared spectroscopy (FTIR) analyses. The starting c‐C9HR presented in yellow color (Gardner color No. 8.4). Under the hydrogenation conditions used (H2pressure 70 bar, 250°C, and 8 h), the ethylenic proton in c‐C9HR was completely removed, but the aromatic rings content remained unaltered and very little change in resin color was observed (Gardner color No.8.1). On the other hand, the starting p‐C9HR contained only unsaturated aromatic proton with Gardner color No.17.1. Under similar conditions, aromatic rings in p‐C9HR were converted to alicyclic rings, and its color was reduced to Gardner color No.5.7. By varying the DH of aromatics in p‐C9HR, two‐step decolorization was observed in which at lower DH (≤10%) the color decreased sharply from 17.1 to 9.3, while further color reduction to 5.7 was obtained when the DH was increased to 94%. It is suggested that both color body and aromatic rings were the main sources contributing to C9HR color. Nevertheless, color stability of the resin during heat treatment was significantly improved by hydrogenation especially at DH ≥ 50%. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
A photoinitiator‐free photosensitive polyimide with low dielectric constant
Authors: Choi Seunghyuk , Lee Seokkyu , Jeon Jihee , An Jaein , Khan Sher Bahadar , Lee Sangyup , Seo Jongchul , Han Haksoo
Published: April 2010

A series of photoinitiator‐free photosensitive polyimides (PSPIs) with lower dielectric constants have been synthesized by reaction of fluorine aromatic diamine, 2,2′‐bis(3‐amino‐4‐hydroxyphenyl)hexafluoropropane diamine (AHHFP) with 3,3′,4,4′‐benzophenonetetracarboxylic dianhydride (BTDA) and a mixture of various mole ratios of 3,3′,4,4′‐benzophenonetetracarboxylic dianhydride (BTDA) and 4,4′‐(hexafluoroisopropylidene)diphthalic anhydride (6FDA) by using solution poly‐condensation reaction at room temperature and further imidization at 180°C. These aromatic polyimides were further acrylated via a reaction with acryloyl chlroride in the presence of triethyl amine to produce negative photoinitiator‐free PSPIs. All the photoinitiator‐free photosensitive polyimides were characterized by FTIR and NMR while their morphologhy was evaluated by X‐ray diffractions study. These newly synthesized PSPIs were evaluated to determine their electrical, thermal, and photolithographic properties. The PSPI (AHHFP‐BTDA‐6FDA [1 : 0.5 : 0.5]) with high mole ratio of 6FDA showed lower dielectric constants of 2.420 at 1 kHz and 2.170 at 1 MHz in capacitance and optical methods, respectively. Further, the acrylated AHHFP‐BTDA showed the highest photosensitivity than other PSPIs. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Kinetics and crystal structure of isothermal crystallization of poly(lactic acid) plasticized with triphenyl phosphate
Authors: Xiao Hanwen , Liu Fen , Jiang Tao , Yeh Jen‐Taut
Published: April 2010

In this article, the spherulitic growth rate of neat and plasticized poly(lactic acid) (PLA) with triphenyl phosphate (TPP) was measured and analyzed in the temperature range of 104–142°C by polarizing optical microscopy. Neat PLA had the maximum value of 0.28 μm/s at 132°C, whereas plasticized PLA had higher value than that of neat PLA, but the temperature corresponding to the maximum value was shifted toward lower one with increasing TPP content. The isothermal crystallization kinetics of neat and plasticized PLA was also analyzed by differential scanning calorimetry and described by the Avrami equation. The results showed for neat PLA and its blends with various TPP contents, the average value of Avrami exponents n were close to around 2.5 at two crystallization temperatures of 113 and 128°C, the crystallization rate constant k was decreased, and the half‐life crystallization time t1/2 was increased with TPP content. For neat PLA and its blend with 15 wt % TPP content, the average value of n was 2.0 and 2.3, respectively, the value of k was decreased, and the value of t1/2 was increased with crystallization temperature (Tc). Further investigation into crystallization activation energy ΔEa of neat PLA and its blend with 15 wt % TPP showed that ΔEa of plasticized PLA was increased compared to neat PLA. It was verified by wide‐angle X‐ray diffraction that neat PLA and its blends containing various TPP contents crystallized isothermally in the temperature range of 113–128°C all form the α‐form crystal. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Use of nanoparticles for improving the foaming behaviors of linear PP
Authors: Zheng W. G. , Lee Y. H. , Park C. B.
Published: April 2010

This research presents the foaming behaviors of linear polypropylene (PP) and PP/clay nanocomposites blown with supercritical CO2. The cell nucleation and expansion behaviors of the linear PP and PP‐based nanocomposites at various clay contents during extrusion foaming are studied. The experimental results indicate that the nano‐particles have a positive impact on improving the cell morphology, the cell density and the expansion ratio of the linear PP foams. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Fractionated crystallization and self‐nucleation behavior of poly(ethylene oxide) in its miscible blends with poly(3‐hydroxybutyrate)
Authors: Pan Pengju , Zhao Li , Zhu Bo , He Yong , Inoue Yoshio
Published: April 2010

The fractionated crystallization and self‐nucleation behavior of poly(ethylene oxide) (PEO) component in the miscible PEO/poly(3‐hydroxybutyrate) (PHB) binary blends were investigated using differential scanning calorimetry (DSC) and small‐angle X‐ray diffraction (SAXS) under different crystallization conditions. The distribution of PEO component in the PEO/PHB blend greatly influences its fractionated crystallization behavior. The active heterogeneities, on which the semicrystalline components in the molten state can nucleate at a small supercooling, are favored to locate out of the interlamellar regions of PHB crystals during the crystallization of PHB component. The PEO component confined in the interlamellar regions of PHB crystals crystallizes at an extremely large supercooling, which is induced by the homogeneous nucleation or less active heterogeneities, while the PEO component expelled out of the interlamellar regions of PHB crystals can crystallize at a small supercooling due to the nucleation induced by active heterogeneities. In addition, the self‐nucleation behavior of PEO component in the PEO/PHB blend is also affected by the active heterogeneities and the distribution of PEO phase in the blend. Different from the block copolymer systems, the PEO component confined into the interlamellar regions of PHB crystals can not be self‐nucleated in the PEO/PHB blend without a nucleating agent (NA). © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Characterization of a clinical polymer‐drug conjugate using multiscale modeling
Authors: Peng Lili X. , Ivetac Anthony , Chaudhari Akshay S. , Van Sang , Zhao Gang , Yu Lei , Howell Stephen B. , McCammon J. Andrew , Gough David A.
Published: April 2010

The molecular conformation of certain therapeutic agents has been shown to affect the ability to gain access to target cells, suggesting potential value in defining conformation of candidate molecules. This study explores how the shape and size of poly‐γ‐glutamyl‐glutamate paclitaxel (PGG‐PTX), an amphiphilic polymer‐drug with potential chemotherapeutic applications, can be systematically controlled by varying hydrophobic and hydrophilic entities. Eighteen different formulations of PGG‐PTX varying in three PTX loading fractions (fPTX) of 0.18, 0.24, and 0.37 and six spatial arrangements of PTX (‘clusters’, ‘ends’, ‘even’, ‘middle’, ‘random’, and ‘side’) were explored. Molecular dynamics (MD) simulations of all‐atom (AA) models of PGG‐PTX were run until a statistical equilibrium was reached at 100 ns and then continued as coarse‐grained (CG) models until a statistical equilibrium was reached at an effective time of 800 ns. Circular dichroism spectroscopy was used to suggest initial modeling configurations. Results show that a PGG‐PTX molecule has a strong tendency to form coil shapes, regardless of the PTX loading fraction and spatial PTX arrangement, although globular shapes exist at fPTX = 0.24. Also, less uniform PTX arrangements such as ‘ends’, ‘middle’, and ‘side’ produce coil geometries with more curvature. The prominence of coil shapes over globules suggests that PGG‐PTX may confer a long circulation half‐life and high propensity for accumulation to tumor endothelia. This multiscale modeling approach may be advantageous for the design of cancer therapeutic delivery systems. © 2010 Wiley Periodicals, Inc. Biopolymers 93: 936–951, 2010.
Synthesis of Fluorine‐Containing Molecular Rotors and Their Assembly on Gold Nanoparticles
Authors: Thibeault Dominic , Auger Michèle , Morin Jean‐François
Published: April 2010

A series of eight rotors containing thiol groups for attachment to gold surfaces and fluorine atoms for solid‐state 19F NMR spectroscopy have been prepared through linear, multistep synthesis. The common rotating part of the rotors (rotator), consisting of a 2,6‐difluorobenzene moiety, is introduced into the rotor structure through an unusual regioselective Sonogashira coupling with 2,6‐difluoro‐1,4‐diiodobenzene. Rotors with different bulky trityl headgroups were prepared, along with their linear, less hindered analogues. These molecular rotors were assembled on gold nanoparticles (AuNPs) and preliminary characterization was performed on these AuNPs in order to study the effects of the sizes of the molecules on the packing behaviour on the AuNP surfaces. As expected, we found that linear molecules adopt more closely packed structures on the surfaces than their bulky analogues. This offers a very promising opportunity to study rotation dynamics at the molecular level by solid‐state NMR spectroscopy.
Calix[6]arene‐Picolinamide Extractants for Radioactive Waste Treatment: Effect of Additional Carboxy Binding Sites in the Pyridine 6‐Positions on Complexation, Extraction Efficiency and An/Ln Separation (Eur. J. Org. Chem. 14/2010)
Authors: Macerata Elena , Sansone Francesco , Baldini Laura , Ugozzoli Franco , Brisach Frederic , Haddaoui Jaouad , Hubscher‐Bruder Véronique , Arnaud‐Neu Françoise , Mariani Mario , Ungaro Rocco , Casnati Alessandro
Published: April 2010

The cover picture shows the complexation of actinide metal ions by picolinamide‐based calix[6]arenes. These ligands possess remarkable efficiency in the extraction of trivalent metal ions even at very high HNO3 concentration and fair selectivity for actinide ions over lanthanide ions, which is useful in the recycling of the spent nuclear fuel. The Partitioning and Transmutation (P&T) strategy would allow the long‐lived minor actinides (Np, Am, Cm) in fast nuclear reactors to be separated and transmutated and would also allow the radiotoxicity in the ultimate waste to be minimized, making nuclear power plants more efficient and sustainable. Details are discussed in the article by M. Mariani, A. Casnati et al. on p. 2675 ff.
Dual CD system in capillary electrophoresis for direct separation of the four stereoisomers of agonist and antagonist melatoninergic ligands
Authors: Lipka Emmanuelle , Danel Cécile , Yous Saïd , Bonte Jean‐Paul , Vaccher Claude
Published: April 2010

In this study, baseline separation of the stereoisomers of six tetrahydronaphthalenic derivatives (agonists and antagonists for the melatonin (N‐acetyl‐5‐methoxytryptamin) binding sites) was successfully achieved using CE and CDs as chiral selectors. The method for the simultaneous chiral separation of the four stereoisomers uses a capillary dynamically coated with polyethylene oxide and a dual CD system. Optimisation was performed first upon the constituents of the CD system, by varying neutral and anionic CD type, size and concentration, at first in mono‐CD systems and subsequently in dual neutral/anionic CD systems. Once these characteristics of the dual CD system were established, operational parameters such as voltage and temperature were then optimised. Under the optimal conditions (i.e. 1.5% w/v of highly S‐β‐CD and 10 mM of γ‐CD in 25 mM phosphate buffer (pH 2.5) as the BGE, separation voltage 20 kV and a temperature of 25°C), complete resolution of the six molecules was accomplished. Preliminary results for repeatability and the migration order of the optimised method are described.
Enantioseparation of amino acids and α‐hydroxy acids on ligand‐exchange continuous beds by capillary electrochromatography
Authors: Puchalska Patrycja , Pittler Elfriede , Trojanowicz Marek , Gübitz Gerald , Schmid Martin G.
Published: April 2010

A new chiral stationary phase based on continuous bed (CB) technology using L‐prolinamide as a chiral selector was prepared. Its ability for enantioseparation of amino acids and α‐hydroxy acids by ligand‐exchange CEC was compared with that of a CB containing L‐4‐hydroxyproline as chiral selector. Preparation was done by a one‐step in situ copolyermerization procedure using methacrylamide as monomer, vinylsulfonic acid as charge providing agent and piperazine diacrylamide as crosslinker. L‐Prolinamide showed marked enantioselective properties for the separation of amino acids and α‐hydroxy acids. Furthermore, we show the possibility of simultaneous enantioseparation of amino acids and α‐hydroxy acids using the CB with L‐4‐hydroxyproline as chiral selector.
Imaging genetics and development: Challenges and promises
Authors: Casey B.J. , Soliman Fatima , Bath Kevin G. , Glatt Charles E.
Published: April 2010

Excitement with the publication of the human genome has served as catalyst for scientists to uncover the functions of specific genes. The main avenues for understanding gene function have been in behavioral genetics on one end and on the other end, molecular mouse models. Attempts to bridge these approaches have used brain imaging to conveniently link anatomical abnormalities seen in knockout/transgenic mouse models and abnormal patterns of brain activity seen in humans. Although a convenient approach, this article provides examples of challenges for imaging genetics, its application to developmental questions, and promises for future directions. Attempts to link genes, brain, and behavior using behavioral genetics, imaging genetics, and mouse models of behavior are described. Each of these approaches alone, provide limited information on gene function in complex human behavior, but together, they are forming bridges between animal models and human psychiatric disorders. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.
Enlarged tracheoesophageal puncture after total laryngectomy: A systematic review and meta‐analysis
Authors: Hutcheson Katherine A. , Lewin Jan S. , Sturgis Erich M. , Kapadia Asha , Risser Jan
Published: April 2010

Background

Enlargement of the tracheoesophageal puncture (TEP) is a challenging complication after laryngectomy with TEP. We sought to estimate the rate of enlarged puncture, associated pneumonia rates, potential risk factors, and conservative treatments excluding complete surgical TEP closure.

Methods

A systematic review was conducted (1978–2008). A summary risk estimate was calculated using a random‐effects meta‐analysis model.

Results

Twenty‐seven peer‐reviewed manuscripts were included. The rate of enlarged puncture and/or leakage around the prosthesis was reported in 23 articles (range, 1% to 29%; summary risk estimate, 7.2%; 95% confidence interval [CI], 4.8% to 9.6%). Temporary removal of the prosthesis and TEP‐site injections were the most commonly reported conservative treatments. Prosthetic diameter (p = .076) and timing of TEP (p = .297) were analyzed as risk factors; however, radiotherapy variables were inconsistently reported.

Conclusion

The overall risk of enlarged puncture seems relatively low, but it remains a rehabilitative challenge. Future research should clearly establish risk factors for enlarged puncture and optimal conservative management. © 2010 Wiley Periodicals, Inc. Head Neck, 2011
Technical refinement of ultrasound‐guided transoral resection of parapharyngeal/retropharyngeal thyroid carcinoma metastases
Authors: Andrews Genevieve A. , Kwon Michael , Clayman Gary , Edeiken Beth , Kupferman Michael E.
Published: April 2010

Background

The transoral approach to the parapharyngeal and retropharyngeal space (PPS/RPS) for the management of well‐differentiated thyroid carcinoma (WDTC) has been previously described in other articles. However, limited exposure with this approach can be a challenge.

Methods

This is a retrospective review of 6 patients who underwent ultrasound‐guided transoral excision of PPS/RPS WDTC metastases from October 2003 to March 2009 in a cancer center setting. Ultrasound‐guided methylene blue dye injection of the node was used in 3 patients to facilitate intraoperative identification. The technique, safety, and feasibility of the procedure are described in this study.

Results

Successful resection of the metastases was accomplished in all cases without intraoperative complication. The 1 definite recurrence was further treated with transmandibular excision.

Conclusion

Transoral excision of PPS/RPS WDTC metastases with ultrasound‐guided methylene blue dye injection into the metastatic node is safe, feasible, and may further improve intraoperative identification of metastases in poorly accessible locations in the head and neck. © 2010 Wiley Periodicals, Inc. Head Neck, 2011
Filamin a mediates HGF/c‐MET signaling in tumor cell migration
Authors: Zhou Alex‐Xianghua , Toylu Aslı , Nallapalli Rajesh K. , Nilsson Gisela , Atabey Neşe , Heldin Carl‐Henrik , Borén Jan , Bergo Martin O. , Akyürek Levent M.
Published: April 2010

Deregulated hepatocyte growth factor (HGF)/c‐MET axis has been correlated with poor clinical outcome and drug resistance in many human cancers. Identification of novel regulatory mechanisms influencing HGF/c‐MET signaling may therefore be necessary to develop more effective cancer therapies. In our study, we show that multiple human cancer tissues and cells express filamin A (FLNA), a large cytoskeletal actin‐binding protein, and expression of c‐MET is significantly reduced in human tumor cells deficient for FLNA. The FLNA‐deficient tumor cells exhibited poor migrative and invasive ability in response to HGF. On the other hand, the anchorage‐dependent and independent tumor cell proliferation was not altered by HGF. The FLNA‐deficiency specifically attenuated the activation of the c‐MET downstream signaling molecule AKT in response to HGF stimulation. Furthermore, FLNA enhanced c‐MET promoter activity by its binding to SMAD2. The impact of FLNA deficiency on c‐MET expression and HGF‐mediated cell migration in human tumor cells was confirmed in primary mouse embryonic fibroblasts deficient for Flna. These data suggest that FLNA is one of the important regulators of c‐MET signaling and HGF‐induced tumor cell migration.
Imatinib response in two GIST patients carrying two hitherto functionally uncharacterized PDGFRA mutations: An imaging, biochemical and molecular modeling study
Authors: Dileo Palma , Pricl Sabrina , Tamborini Elena , Negri Tiziana , Stacchiotti Silvia , Gronchi Alessandro , Posocco Paola , Laurini Erik , Coco Paola , Fumagalli Elena , Casali Paolo G. , Pilotti Silvana
Published: April 2010

Beside the well known “in vivo” and “in vitro” Imatinib resistant D842V mutation in PDGFRA receptor, very few are the information concerning the “in vivo” Imatinib activity with respect to the other PDGFRA mutations for which only “in vitro” data are available. Two patients carrying PDGFRA mutations in exons 18 (involving residues DIMH842‐845) and 12 (V561D), respectively, were treated with Imatinib at a dose of 400 mg/day. According to Response Evaluation Criteria in Solid Tumors criteria, after a median treatment of 7 months both patients showed clinical partial response, and underwent surgery of the minimal residual disease. Tumor response was confirmed pathologically. In both patients, analyses of PDGFRA performed on pre‐ and/or post‐treatment material were compared to affinity data of the mutated receptor towards the inhibitor. Molecular modeling evidence was found to be consistent with sensitivity of mutated PDGFRA receptors to Imatinib. Thus, the “in vivo” evidence that these two mutations of PDGFRA are sensitive to Imatinib was confirmed by a multidimensional approach comprising “in silico” experiments that, in association to molecular and biochemical analyses, constitutes a powerful tool to predict Imatinib sensitivity, clinically beneficial in the treatment of these tumors with molecularly targeted therapies.
Protein causes a glycemic response
Authors: Whelan William J. , Ghanchi Hammad , Ricciardi Michael
Published: April 2010

The glycemic index is used to compare the extent to which the blood glucose level increases following the consumption of foods containing digestible carbohydrate and is considered to be zero, or not measurable, if the food, such as protein, is carbohydrate‐free. We have found that after overnight fasting, the consumption of several varieties of meat caused significant increases in blood glucose levels. We consider these possibly to be because of gluconeogenesis from the digested protein. It is a curious feature that in two instances the response was inversely related to the amount of meat consumed, over the range from 26 to 78 g of protein. © 2010 IUBMB IUBMB Life, 62(6): 481–483, 2010
Type‐IV pili spectroscopic markers: Applications in the quantification of piliation levels inMoraxella boviscells by a FT‐IR ANN‐based model
Authors: Bosch Alejandra , Prieto Claudia , Serra Diego Omar , Martina Pablo , Stämmler Maren , Naumann Dieter , Schmitt Jürgen , Yantorno Osvaldo
Published: April 2010

Type‐IV pili are cell surface organelles found in a wide variety of Gram‐negative bacteria. They have traditionally been detected by electron microscopy and ELISA techniques. However, these methodologies are not appropriate for the rapid discrimination and quantification of piliated and nonpiliated cells in industrial or field conditions. Here, the analysis of FT‐IR spectra of piliated, nonpiliated and shearedMoraxella boviscells, together with purified pili suspensions spectra, allowed the identification of 3 IR regions associated to spectroscopic markers of Type‐IV pili: 1750–1600, 1450–1350 and 1280–950 cm–1. Such IR‐specific markers were found for piliated cells grown in different culture systems (liquid or solid media), independently of the strain or pili serotype. They were also sensitive to pili expression levels. Therefore, on the bases of these specific spectral features, an FT‐IR ANN‐based model was developed to classify piliation levels in 5 distinct groups. An overall classification rate of almost 90% demonstrates the strong potential of the ANN system developed to monitorM. boviscultures in vaccine production. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Phase‐contrast hard X‐ray microscopy using synchrotron radiation for the diagnosis of onychomycosis
Authors: Lee Onseok , Ha Seunghan , Lee Gunwoo , Kim Jaeyoung , Huang Jungyun , Jin Kyeongsik , Oh Chilhwan
Published: April 2010

Onychomycosis, or fungal infection of the nail, is a disease seen frequently in clinical settings. However, the rates of positive identification using potassium hydroxide preparations or fungal cultures are relatively low. Precise diagnosis is possible via histopathologic examination to monitor the existence of fungus and performance of a fungal culture for confirmation. Phase‐contrast hard X‐ray microscopy using synchrotron radiation provides 70‐nm spatial resolution and enables imaging of minute internal cellular structures. This study confirms the feasibility of diagnosing onychomycosis using a phase‐contrast hard X‐ray microscope developed at 1B2 beam line using a Pohang light source. Microsc. Res. Tech. 73:1110–1114, 2010. © 2010 Wiley‐Liss, Inc.
Evaluation of the Environmental Protection Agency/National Weather Service Ultraviolet Index Forecast against independent UV measurements: Phoenix Arizona (2000–2006)
Authors: Svoma Bohumil M. , DeBiasse Kimberly , Nolte Jessica , Busby Bradley , Beeson Carolyn , Cerveny Randall
Published: April 2010

The effectiveness of the National Weather Service (NWS) Ultraviolet Index (UVI) forecast is evaluated for one of the largest United States metropolitan areas that annually experiences exceedingly large dosages of ultraviolet (UV) radiation, Phoenix Arizona (AZ). Data were collected from Arizona Desert Testing LLC sited at Wittmann AZ, the Volkswagen Arizona Proving Grounds sited at Maricopa AZ and Atlas Material Testing Technology LLC, DSET Laboratories sited at New River AZ. In general, over 50% of the variance (r = 0.709) in UV radiation is shared between the datasets from the three independent facilities although the geographic distances between sites are relatively large. Overall correlations between the NWS UVI forecasts and the data from the three independent testing facilities are surprisingly weak when the annual cycle is removed from all datasets with less than 21% of the variance in UV data accounted for by the NWS UVI forecast. The lowest correspondence occurred during the summer months with June displaying the lowest correlations, often insignificant at the 0.05 level. To account for these lower correlations, we considered daily sky cover and air quality observations of particles with a diameter less than 10 µm (PM10). Our analyses suggest that large amounts of PM10 present during the late spring and early summer are a likely cause for low correspondence between the NWS UVI and UV data in June. Given the unexpectedly low overall correlations, optical depth may need to be better incorporated in the NWS UVI forecast process through pollution forecasts in order to increase the correspondence between the NWS UVI and actual UV irradiance. Copyright © 2010 Royal Meteorological Society
Early‐onset metaphyseal chondrodysplasia type Schmid associated with a COL10A1 frame‐shift mutation and impaired trimerization of wild‐type α1(X) protein chains
Authors: Mäkitie Outi , Susic Miki , Cole William G.
Published: April 2010

Both dominant‐negative and haploinsufficiency effects have been proposed in the pathogenesis of metaphyseal chondrodysplasia type Schmid (MCDS) due to nonsense and frame‐shift mutations of COL10A1. This study examines these alternative effects. A proband with typical early‐onset MCDS was ascertained and COL10A1 sequencing undertaken. The assembly of trimeric collagen X molecules was studied using in vitro coupled transcription and translation of wild‐type and mutant α1(X) cDNAs. The proband was heterozygous for a unique COL10A1 mutation, c.1735_1739del5ins22. Mutant protein chains, with the corresponding p.G579fsX611 change, failed to spontaneously trimerize. When wild‐type α1(X) chains were translated alone, 57 ± 7% of the chains assembled into stable collagen X trimers. Trimerization of wild‐type chains was significantly reduced to 33 ± 6% when translated in 1:1 mixtures with p.G579fsX611 α1(X) chains. The protein assembly assay showed that the mutant chains exerted a dominant‐negative effect on collagen X assembly. Previous studies indicate that nonsense‐mediated decay, activation of endoplasmic reticulum, and unfolded protein responses as well as altered chondrocyte differentiation are the major determinants of phenotypic severity and age of presentation. We speculate that complete loss of mutant transcripts yields COL10A1 haploinsufficiency and late clinical presentation while incomplete loss of mutant transcripts yields dominant‐negative effects with early clinical presentation. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:1497–1501, 2010
The effects of sintering and shot peening processes on the fatigue strength
Authors: Iynen O. , Eksi A. K. , Bircan D. A. , Dilek M.
Published: April 2010

Alumix 431 metal powders have been used in this study since they are widely used in the industrial applications. First, Alumix 431 powders were compacted at 400 MPa pressure under room temperature (RT). Then, pressed specimens were sintered separately at 600 and 620°C for 1h N2. Densities were measured for the different temperatures in order to examine the effects of the sintering on density. Improvement of green density was observed to have enhanced approximately 86 and 90% according to theoretical density (2, 786 g/cm3) as a result of the sintering condition at 600 and 620°C, respectively. After sintering a group of specimen was shot peened with the intensities in 12 and 16A. To investigate mechanical properties of as sintered (unpeened) and shot peened samples, tensile and fatigue tests were performed. It was determined that shot peening improved the fatigue strength about 10 and 15% in 12 and 16A intensities, respectively. In addition, fractured specimens after tensile tests were used for Micro‐Hardness measurements, and for metallographic analysis by, optical microscopy (OM) and scanning electron microscopy (SEM) tests further specimens were examined.

Für diese Arbeit wurden die Metallpulver Alumix 431 ausgewählt, die in der industriellen Praxis häufig verwendet werden. Zuerst wurde das Metallpulver Alumix 431 bei einem Pressdruck 400 MPa unter Raumtemperatur kompaktiert. Danach wurden die gepressten Proben bei 600 und 620°C Temperatur jeweils 60 Minuten in N2‐Atmospäre gesintert. Um die Auswirkung des Sinterns auf die Dichte zu beobachten, wurden bei unterschiedlichen Temperaturen hergestellte Proben untersucht. Nach der Kompaktierung wurden unter den Temperaturen 600 und 620°C 86% bzw. 90% der theoretischen Dichte erreicht. Dies zeigt, dass die gepresste Dichte durch das unterschiedliche Sinterlegierungsverhalten zunimmt. Nach der Sinterung wurde mit einer Intensität von 12A und 16A ein Teil der Proben kugelgestrahlt. Um die Eigenschaften der gestrahlten und nicht gestrahlten Proben zu untersuchen, wurden Ermüdungsfestigkeitsversuche durchgeführt. Das Kugelstrahlen erhöht die Ermüdungsfestigkeit etwa um 10 bis 15%. Außerdem wurden die nach dem Zugversuch erhaltenen Bruchstücke für Mikrohärtenmessungen verwendet. Die metallographischen Untersuchungen der Proben wurde im Licht‐Mikroskop (OM) und Raster‐Elektronenmikroskop (SEM) untersucht.
The equivalent stress on the critical plane determined by the maximum covariance of normal and shear stresses
Authors: Walat Karolina , Lagoda Tadeusz
Published: April 2010

The paper presents a new form of the stress criterion of multiaxial random fatigue. The criterion has been defined as a sum of normal and shear stresses with weight coefficients on the critical plane defined as the plane where the maximum covariance between shear and normal stresses occurs. Two forms of the criterion have been proposed.
Evaluation of vehicle substances on vitamin D bioavailability: A systematic review
Authors: Grossmann Ruth E. , Tangpricha Vin
Published: April 2010

Vitamin D insufficiency is a common medical condition. Vitamin supplements can be ingested to improve vitamin D status. It is not known if the vehicle substance that is combined with the vitamin D tablet influences the bioavailability of vitamin D. The purpose of this review is to examine the impact of different vehicles on vitamin D bioavailability. A comprehensive literature search identified studies that directly compared the absorption of vitamin D from two or more vehicles. The change in mean serum 25(OH)D per average daily dose of vitamin D supplemented was calculated and compared among the studies. We identified four clinical studies that compared two different vehicles of vitamin D. Vitamin D in an oil vehicle produced a greater 25(OH)D response than vitamin D in a powder or an ethanol vehicle in healthy subjects. There are limited studies that have compared the influence of the vehicle substance on vitamin D bioavailability. Future studies should examine bioavailability among different vehicle substances such as oil, lactose powder, and ethanol and examine if there are any differences in bioavailability among different patient populations including those with fat malabsorption.
Effect of maternal age on the developmental competence and progression of nuclear maturation in bovine oocytes
Authors: Yamamoto T. , Iwata H. , Goto H. , Shiratuki S. , Tanaka H. , Monji Y. , Kuwayama T.
Published: April 2010

Progression of meiotic division in oocytes and early embryonic development are affected by oocytes quality. In most mammals, oocyte quality declines with increase in maternal age. The main aim of the present study is to investigate the effect of maternal age on developmental competence, progression of meiotic division, and associated kinetics of maturation promoting factor (MPF) activity in bovine oocytes. Oocytes were collected from the ovaries of young and old cows (here after referred to as young cow oocytes and old cow oocytes, respectively). When old cow oocytes were matured and fertilized in vitro, the rate of abnormal fertilization was greater than that in young cow oocytes. Moreover, progression of nuclear maturation and activation of MPF during oocyte maturation (or inactivation of MPF and formation of pronucleus after insemination) were faster in old cow oocytes than in young cow oocytes. Relative expression of cyclin B, cyclin‐dependent kinase 1 and MAD2 transcripts in either immature or mature oocytes did not differ between the two groups. When cumulus cells (CC) were removed and denuded oocytes were cultured, there was no difference in the progression of nuclear maturation between the two age groups. Moreover gap junctions between oocytes and CC disappeared more rapidly during maturation of old cow oocytes than of young cow oocytes. These results suggest that the fertilization ability of old cow oocytes is low and that premature progression of meiotic division in these oocytes is partly due to impaired oocyte–CC gap junctions communication. Mol. Reprod. Dev. 77: 595–604, 2010. © 2010 Wiley‐Liss, Inc.