bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular and Morphometrical Revision of theZaprionus tuberculatusSpecies Subgroup (Diptera: Drosophilidae), with Descriptions of Two Cryptic Species
Authors: Yassin Amir
Published: November 2008

Zaprionus is an important drosophilid genus in the Afrotropical region. Here, two new species, Z. burlai n. sp. and Z. tsacasi n. sp., are described from Tanzania and São Tomé, respectively. The two species show incomplete reproductive isolation with Z. tuberculatus Malloch and Z. sepsoides Duda, respectively, with intercrosses producing fertile females but sterile males. The latter two have long been considered sibling species and together with three other species (Z. mascariensis Tsacas & David, Z. kolodkinae Chassagnard & Tsacas, and Z. verruca Chassagnard & McEvey) form the tuberculatus subgroup. The phylogenetic relationships of these seven species of the subgroup were revised in light of mitochondrial (COII) gene sequences and wing morphometrics. Mitochondrial DNA firmly distinguished most of the species, except for a triad of Z. tuberculatus, Z. verruca, and Z. burlai. Wing morphometrics was able to distinguish between closely related species and also indicated the altitudinal origin of each species. Most species can be identified through internal anatomy of the reproductive system (testis and seminal receptacle lengths), and the discovery of the new species with incomplete reproductive isolation may help in understanding the genetic basis of this variation through interspecific hybridization. The molecular phylogeny reconfirmed the Malagasy origin of the subgroup during the Late Pliocene. Colonization of Africa probably involved two independent events during the Pleistocene.
Molecular Design of Superabsorbent Polymers for Organic Solvents by Crosslinked Lipophilic Polyelectrolytes
Authors: Ono Toshikazu , Sugimoto Takahiro , Shinkai Seiji , Sada Kazuki
Published: November 2008

Molecular design of lipophilic polyelectrolyte gels as superabsorbent polymers that exhibit a high degree of swelling in less‐polar and nonpolar organic solvents is demonstrated. A small amount of tetraalkylammonium tetraphenylborate with long alkyl chains as a lipopholic ion pair is incorporated into crosslinked polyacrylates with variable alkyl chain lengths to provide novel lipophilic polyelectrolyte gels. Their swelling degree becomes more than 100 times as much as their dried weights in various organic solvents. The high effectiveness of the swellable solvents shifts to the polar ones by decreasing the length of the alkyl chain. Swelling or collapsing of the lipophilic polyelectrolyte gels originates from both incompatibility of the polymer chains in the media and dissociation of ionic groups. Thus, a unique superabsorbency is observed when the polymer chains have good compatibility with the solvents and the solvents have relatively high polarities enough to dissociate the ionic groups. By varying the polarity of the neutral monomer in these polyelectrolyte gels, the design of gels that can absorb solvents of nearly any polarity is demonstrated.
New data on the late Neandertals: Direct dating of the Belgian Spy fossils
Authors: Semal Patrick , Rougier Hélène , Crevecoeur Isabelle , Jungels Cécile , Flas Damien , Hauzeur Anne , Maureille Bruno , Germonpré Mietje , Bocherens Hervé , Pirson Stéphane , Cammaert Laurence , De Clerck Nora , Hambucken Anne , Higham Thomas , Toussaint Michel , van der Plicht Johannes
Published: November 2008

In Eurasia, the period between 40,000 and 30,000 BP saw the replacement of Neandertals by anatomically modern humans (AMH) during and after the Middle to Upper Paleolithic transition. The human fossil record for this period is very poorly defined with no overlap between Neandertals and AMH on the basis of direct dates. Four new 14C dates were obtained on the two adult Neandertals from Spy (Belgium). The results show that Neandertals survived to at least ≈36,000 BP in Belgium and that the Spy fossils may be associated to the Lincombian–Ranisian–Jerzmanowician, a transitional techno‐complex defined in northwest Europe and recognized in the Spy collections. The new data suggest that hypotheses other than Neandertal acculturation by AMH may be considered in this part of Europe. Am J Phys Anthropol, 2009. © 2008 Wiley‐Liss, Inc.
Grafting of cotton fiber by water‐soluble cyclodextrin‐based polymer
Authors: Shown I. , Murthy C. N.
Published: November 2008

β‐cyclodextrin (CD)‐based linear water‐soluble polymers were synthesized in a controlled manner by a one‐pot synthesis method. The synthesized water‐soluble polymer was covalently fixed onto cotton surfaces by a polycondensation reaction at controlled conditions. Grafting on cotton fibers transfers the cyclodextrin properties onto its surface. The grafting occurred through the formation of a crosslink between hydroxyl groups of cotton and CD polymer. This was confirmed using FTIR spectroscopy, DSC, tensile strength, computer color matching, and solvent fastness analysis. The tensile strength of modified fiber samples was unchanged as compared to that of unmodified fiber samples. The percentage of grafting depended on a number of parameters and specifically on (i) temperature, (ii) time, and (iii) pH of the reaction medium. Similarly, under optimum conditions the weight increase on cotton fabric due to the grafting reaction could reach 10–15 wt % The grafted cotton fabric shows good dyeability and solvent fastness properties. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Macroporous chelating resins incorporating heterocyclic functional groups via hydrophilic poly(ethylene oxide) spacer arms. II. Adsorption properties
Authors: Ji Chunnuan , Qu Rongjun , Xu Qiang , Sun Changmei , Wang Chunhua , Cheng Yucui , Song Yanpeng
Published: November 2008

Several new chelating resins prepared from macroporous chloromethylated polystyrene‐co‐divinylbenzene by either direct attachment of the heterocyclic functional groups, such as 2‐aminopyridine, 2‐amino‐5‐methylthio‐1,3,4‐thiadizole, 2‐amino‐5‐ethyl‐1,3,4‐thiadizole, and 2‐mercaptobenzothiazole, to the polymeric matrix or through different hydrophilic spacer arms were tested for the adsorption properties toward Hg2+, Ag+, Cd2+, and Pb2+ in an ammonium acetate buffer solution of pH 3.0. The results show that these resins exhibited a high affinity for Hg2+ and Ag+. The introduction of hydrophilic spacer arms between the polymeric matrix and heterocyclic functional groups resulted in an increase in the hydrophilicity and adsorption capacity of the resins. The presence of spacer arms made the kinetics of adsorption faster. The influence of the length of the spacer arm on the adsorption properties was also investigated. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis and characterization of novel optically active poly(urethane urea)s: Effect of left/right rotation conformation
Authors: Wang Zhi‐Qiang , Zhou Yu‐Ming , Ye Xiao‐Yun , Chen Jing , Sun Yan‐Qing
Published: November 2008

Helical R/S‐poly(urethane urea)s (R/S‐HPUUs) were synthesized successfully with R/S‐1,1′‐binaphthyl‐2′,2‐diol, toluene 2,4‐diisocyanate, and 1,4‐diaminobenzene by a simple hydrogen‐transfer addition reaction. The structure and optical properties of R/S‐HPUUs were investigated systematically with Fourier transform infrared spectroscopy, 1H‐NMR spectra, absorption and circular dichroism, thermogravimetry, differential scanning calorimetry, and X‐ray diffraction measurements. Fourier transform infrared spectra showed that all the NH and carbonyl groups in R/S‐HPUUs were hydrogen‐bonded. R‐HPUU and S‐HPUU were two enantiomorphs with wonderful mirror‐image symmetry according to circular dichroism spectroscopy analysis. R/S‐HPUUs exhibited optical activity, and the optical rotations were +54.7 and −60.7°, respectively. R/S‐HPUUs showed excellent thermal stability because of the plane‐bifurcated interchain hydrogen bonds and helical stereostructures according to thermogravimetry, differential scanning calorimetry, and X‐ray diffraction analysis. Moreover, the left‐handed rotation was more stimulative for the construction of hydrogen bonds than the right‐handed rotation, so S‐HPUU showed higher thermal stability and better crystallizability. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Influence of the equatorial warm water pool on the tropical cyclogenesis: an aqua planet experiment
Authors: Yoshioka Mayumi K. , Kurihara Yoshio
Published: November 2008

Aqua planet experiments were performed to investigate any favorable environmental conditions for tropical cyclogenesis with a high‐resolution atmospheric general circulation model. Zonally localized enhanced sea surface temperature distributions on the equator modify atmospheric circulation east–west asymmetrically. Tropical cyclogenesis is observed in the off‐equatorial western half of the warm water pool where an enhanced distribution of absolute vorticity is produced. The region associated with the equatorward planetary vorticity transport contributes to make the western half of the pool notably favorable for generating tropical cyclones. Copyright © 2008 Royal Meteorological Society
The third and fourth transmembrane domains of Slc11a1: Comparison of their structures and positioning in phospholipid model membranes
Authors: Qi Haiyan , Yang Lei , Xue Rong , Song Yuande , Wang Shuo , Li Fei
Published: November 2008

Interactions of two peptides TM3 and TM4, corresponding to the third and fourth transmembrane domains of a divalent metal‐ion transporter Slc11a1, respectively, with phospholipid model membranes, including zwitterionic dimyristoylphosphatidylcholine (DMPC) and anionic dimyristoylphosphatidylglycerol (DMPG), are studied in a wide range of peptide‐to‐lipid (P:L) ratios, and the secondary structures and positioning of the peptides in the lipid bilayers are analyzed, using differential scanning calorimetry (DSC), circular dichroism (CD), and fluorescence techniques. DSC and fluorescence results indicate that both peptides are inserted in the phospholipid bilayers. TM4 is buried in the bilayers more deeply and the insertion position is less affected by pH values, whereas TM3 is less deeply embedded and the position is remarkably shifted toward the direction of the bilayer surface with increasing pH value. The incorporation of TM4 in both lipids causes more perturbation to the packing of the hydrophobic chains of the lipids than TM3. Moreover, the perturbation of TM3 to the lipid packing is pH dependent, whereas the perturbation of TM4 is less pH dependent but with an unusually larger change in the enthalpy of the main transition at pH 5.5 than those at pH 4 and 7. CD data demonstrate that the main discrimination between the secondary structures of TM4 and TM3 is the α‐helix content, more helicity for TM4 than TM3 in both lipids. The folding of the peptides is also affected by the composition of the phospholipids. Anionic lipid DMPG induces more α‐helical folding than neutral lipid DMPC for both peptides. © 2008 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 92: 52–64, 2009.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
“Roll‐over” Cyclometalation of 2,2′‐Bipyridine Platinum(II) Complexes in the Gas Phase: A Combined Experimental and Computational Study
Authors: Butschke Burkhard , Schlangen Maria , Schröder Detlef , Schwarz Helmut
Published: November 2008

In a combined experimental/computational investigation, the gas‐phase behavior of cationic [Pt(bipy)(CH3)((CH3)2S)]+ (1) (bipy=2,2′‐bipyridine) has been explored. Losses of CH4 and (CH3)2S from 1 result in the formation of a cyclometalated 2,2′‐bipyrid‐3‐yl species [Pt(bipy−H)]+ (2). As to the mechanisms of ligand evaporation, detailed labeling experiments complemented by DFT‐based computations reveal that the reaction follows the mechanistically intriguing “roll‐over” cyclometalation path in the course of which a hydrogen atom from the C(3)‐position is combined with the Pt‐bound methyl group to produce CH4. Activation of a CH‐bond of the (CH3)2S ligand occurs as well, but is less favored (35 % versus 65 %) as compared to the C(3)H bond activation of bipy. In addition, the thermal ion/molecule reactions of [Pt(bipy−H)]+ with (CH3)2S have been examined, and for the major pathway, that is, the dehydrogenative coupling of the two methyl groups to form C2H4, a mechanism is suggested that is compatible with the experimental and computational findings. A hallmark of the gas‐phase chemistry of [Pt(bipy−H)]+ with the incoming (CH3)2S ligand is the exchange of one (and only one) hydrogen atom of the bipy fragment with the CH bonds of dimethylsulfide in a reversible “roll‐over” cyclometalation reaction. The PtII‐mediated conversion of (CH3)2S to C2H4 may serve as a model to obtain mechanistic insight in the dehydrosulfurization of sulfur‐containing hydrocarbons.
Synchronized reentrant flux reversal of multiple FeSiB amorphous wires having large output
Authors: Takajo Minoru , Yamasaki Jiro
Published: November 2008

A technique to synchronize the reentrant flux reversal of the multiple magnetostrictive Fe77.5Si7.5B15 amorphous wires was developed using a flux keeper of amorphous ribbons that contacted the wire ends. It is found that the characteristics of the reentrant flux take place respectively at almost the same time in the three Fe‐Si‐B amorphous wires with a diameter of 65 or 95µm. This phenomenon can be explained by considering the strong magnetic coupling of wires and amorphous ribbon by stray field from each wire end. As a result, the magnitude of the induced voltage in the sense coil is increased in proportion to the multiplication of the number of wires. © 2008 Wiley Periodicals, Inc. Electron Comm Jpn, 91(5): 19–25, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10111
Proposal and evaluation of a gas engine and gas turbine hybrid cogeneration system in which cascaded heat is highly utilized
Authors: Pak Pyong Sik
Published: November 2008

A high‐efficiency cogeneration system (CGS) is proposed for utilizing high‐temperature exhaust gas (HTEG) from a gas engine (GE). In the proposed system, for making use of heat energy of HTEG, H2O turbine (HTb) is incorporated and steam produced by utilizing HTEG is used as working fluid of HTb. HTb exhaust gas is also utilized for increasing power output and for satisfying heat demand in the proposed system. Both of the thermodynamic characteristics of the proposed system and a gas engine CGS (GE‐CGS) constructed by using the original GE are estimated. Energy saving characteristics and CO2 reduction effects of the proposed CGS and the GE‐CGS are also investigated. It was estimated that the net generated power of the proposed CGS has been increased 25.5% and net power generation efficiency 6.7%, compared with the original GE‐CGS. It was also shown that the proposed CGS could save 27.0% of energy consumption and reduce 1137 t‐CO2/y, 1.41 times larger than those of GE‐CGS, when a case study was set and investigated. Improvements of performance by increasing turbine inlet temperature were also investigated. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(3): 37– 45, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20708
Magnetostrictive effect type force (strain) sensor using mutual induction of planar coils
Authors: Koga Fumitaka , Sasada Ichiro
Published: November 2008

A new structure is proposed for the magnetostrictive effect type force sensors using a pickup head layered with magnetostrictive foil and pair of planar coils. Mutual coupling between two planar coils is used as a measure of force applied to the magnetostrictive foil. In this type of force sensor, the output voltage is zero when force is zero, and the planar coils with electric wires can be put on and taken off easily because the magnetostrictive foil does not need a current contact. Basic characteristics of the force sensors are examined using Metglas2605SC amorphous foil glued to the side of an aluminun square bar of 15 mm×15 mm cross‐sectional area and a pair of 16‐turn planar coils. Sensitivity was 38.4 mV/Nm [1.57 mV/μϵ (ϵ = δ l/l)] at the coil excitation condition of 1 MHz, 60 mA. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(3): 1–7, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20740
Characteristic analysis and trial manufacture of permanent‐magnetic type linear generator
Authors: Takahara Kenji , Ohsaki Shingo , Itoh Yuzo , Ohyama Kazuhiro , Kawaguchi Hideki
Published: November 2008

This paper describes the design and trial manufacture of a linear generator which can convert any mechanical vibration of an automobile to electrical energy. A mover, which includes permanent magnets, is linearly driven through a stator by vibrations. The Nd‐Fe‐B magnets in the mover are placed facing the same magnetic poles in order to produce a change of magnetic flux in the coils of the stator. The coils are placed in the stator with the same intervals as the magnets. Successive coils are wound in opposite directions and are connected in series. A magnetic iron core covering the stator makes the magnetic flux extend through the case and reduces flux canceling in the coils of the stator. The distribution of the magnetic field, the electromotive force, and the driven power of the mover were calculated by numerical simulations in order to determine the size of the linear generator. A linear generator and experimental apparatus were built on the basis of the simulation. The performance characteristics were tested in experiments, and the produced linear generator was confirmed to be useful as an onboard auxiliary power supply. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(3): 94– 100, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20751
Reaction of (Carbonyl)triruthenium with Acetylferrocene Thiosemicarbazone: Synthesis, X‐ray Diffraction, and Insight into the Solution Structures
Authors: Yang Jing‐Mu , Hu Bin , Hu Xiao‐Xue , Xia Chun‐Gu
Published: November 2008

Reaction of acetylferrocene thiosemicarbazone [L] with Ru3(CO)12 was investigated. Two new complexes, Ru3(CO)9[L‐H] (1) and Ru2(CO)4[L]2 (2) were isolated. They were characterized by IR, 1H NMR, and 13C NMR spectroscopic analysis. The crystal structures of 1 and 2 were also determined. In trinuclear cluster 1, the acetylferrocene thiosemicarbazone ligand was deprotonated and acted as an N,S‐chelating ligand as well as a sulfur bridge. Dinuclear compound 2 is the first bis(cycloruthenated acetylferrocene thiosemicarbazone) carbonyl derivative. This complex contains two ruthenium atoms in a dinuclear structure with a Cferrocene, N, S2, and (CO)2 coordination sphere for each ruthenium atom, as both L ligands act as a Cferrocene, N, S2 chelate, and sulfur bridge. The behavior of 1 and 2 under electrospray ionization mass spectrometry (ESI‐MS) was studied and the key intermediate Ru(CO)2[L‐H] (3) in the formation of 2 was directly detected in the reaction solution.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Synthesis and Biological Evaluation of Sugars Containing α,β‐Unsaturated γ‐Lactones
Authors: Xavier Nuno M. , Silva Sandrina , Madeira Paulo J. A. , Florêncio M. Helena , Silva Filipa V. M. , Justino Jorge , Thiem Joachim , Rauter Amélia P.
Published: November 2008

The stereocontrolled synthesis of new sugar derivatives carrying the α,β‐unsaturated δ‐lactone (butenolide) moiety is described. Sugar‐fused or sugar‐linked butenolides can be constructed by an efficient reaction sequence involving Wittig olefination of 3‐ or 5‐keto sugars and intramolecular cyclization of the intermediate γ‐hydroxy α,β‐unsaturated esters. The antimicrobial activities of the products and that of a known sugar‐derived pyranoid α,β‐unsaturated δ‐lactone were investigated against six pathogenic bacteria and six fungi. The pyranoid α,β‐unsaturated δ‐lactone 29 proved to be the most active compound in this series towards the plant pathogenic fungi Colletotrichum coffeanum (coffee berry disease) and Pyricularia oryzae (rice blast disease).(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Plasmapheresis and intravenous immune globulin for the treatment of D alloimmunization in pregnancy
Authors: Novak Deborah J. , Tyler Lisa N. , Reddy Ramakrishna L. , Barsoom Michael J.
Published: November 2008

The alloimmunized pregnancy can result in fetal and newborn mortality due to fetal anemia. Control of fetal anemia has not been possible until recently, and management consists of following the degree of fetal anemia during gestation until intrauterine transfusion is feasible to support the fetus until delivery. Cordocentesis and intrauterine transfusion have potential complications that have been well documented. Control of fetal anemia via immune modulation utilizing plasmapheresis and intravenous immune globulin administration has been attempted alone and in combination with varying results. We present a case report of an Rh(D) alloimmunized pregnancy, in which successful management consisted of initial therapeutic plasmapheresis (TPE) followed by intravenous immunoglobulin (IVIG) administration until delivery at 37 weeks gestation without the need for intrauterine transfusion. J. Clin. Apheresis, 2008. © 2008 Wiley‐Liss, Inc.
The use of olive mill wastewater by wild type Yarrowia lipolytica strains: medium supplementation and surfactant presence effect
Authors: Lopes Marlene , Araújo Carla , Aguedo Mário , Gomes Nelma , Gonçalves Cristiana , Teixeira José António , Belo Isabel
Published: November 2008

BACKGROUND: The aim of this work was to study the ability of two different wild type strains of the yeast Yarrowia lipolytica to grow on olive mill wastewater (OMW) and their potential to produce high‐value products such as lipases. Factors that affect cellular growth and OMW degradation were studied, such as nitrogen supplementation, cells concentration and surfactant addition.

RESULTS: Both strains, W29 and IMUFRJ 50682, were able to grow in OMW with 19 g L−1 of COD and approximately 800 mg L−1 of total phenols concentration. The strain W29 presented the highest potential for extracellular lipase production in OMW medium. Lipase productivity was improved by the medium supplementation with ammonium sulphate up to 6 g L−1, leading to 80% of COD degradation and 70% of total phenols reduction. The surfactant Tween 80 enhanced cell growth and COD degradation, but had a negative effect on lipase activity.

CONCLUSIONS Y. lipolytica has a great potential for OMW valorisation by its use as culture medium for biomass and enzymes production. The operating conditions that favoured lipase production differ from the conditions that improve COD reduction. Copyright © 2008 Society of Chemical Industry
Simultaneous saccharification and fermentation of sludge‐containing cassava mash for batch and repeated batch production of bioethanol by Saccharomyces cerevisiae CHFY0321
Authors: Choi Gi‐Wook , Moon Se‐Kwon , Kang Hyun‐Woo , Min Jiho , Chung Bong‐Woo
Published: November 2008

BACKGROUND: The aim of this study was to examine the repeated batch production of bioethanol from sludge‐containing cassava mash as starchy substrate by flocculating yeast to improve volumetric bioethanol productivity and to simplify the process of a pre‐culture system.

RESULTS: For the repeated batch production of bioethanol using cassava mash, the optimal recycling volume ratio was found to be 5%. The repeated batch fermentation was completed within 36 h, while the batch fermentation was completed after 42 h. Volumetric productivity, final ethanol concentration, and ethanol yield were attained to 2.15 g L−1 h−1, 83.64 g L−1, and 85.15%, respectively. Although cell accumulation in the repeated batch process is difficult due to the cassava mash, the repeated batch process using Saccharomyces cerevisiae CHFY0321 could exhibited 10‐fold higher initial viable cell number (1.7 × 107 CFU mL−1) than that of the batch process.

CONCLUSION: The liquefied cassava powder was directly used for the repeated batch process without removal of sludge. Repeated batch bioethanol production by simultaneous saccharification and fermentation using self‐flocculating yeast could reduce process costs and accelerate commercial applications. This result was probably due in part to the effect of the initial viable cell density. Copyright © 2008 Society of Chemical Industry
A simple method for biocatalyst immobilization using PVA‐based hydrogel particles
Authors: Fernandes Pedro , Marques Marco P.C. , Carvalho Filipe , Cabral Joaquim M.S.
Published: November 2008

BACKGROUND: The aim of this study was to evaluate the feasibility of enzyme immobilization in PVA particles through extrusion of LentiKat®Liquid in polyethylene glycol. Inulinase, with invertase activity for sucrose hydrolysis, was used as model system.

RESULTS: Inulinase was effectively immobilized in PVA particles. The pH optimum of the enzyme activity was broadened for lower pH values. Mechanical instability of the PVA under prolonged incubation above 55 °C was observed. A 1.8‐fold increase in the apparent KM (Michaelis constant) suggests diffusion limitations as a result of immobilization. The immobilized biocatalyst exhibited considerable operational stability, since a decrease of roughly 10% in the product yield after 24 h biotransformation runs was observed in trials performed at 50 °C, following 20 repeated, consecutive batches.

CONCLUSION: The results obtained highlight the potential of PVA‐based particles obtained through extrusion into PEG for the production of suitable biocatalysts for application in large‐scale processes. Copyright © 2008 Society of Chemical Industry
Quantitative evaluation of bone resorption activity of osteoclast‐like cells by measuring calcium phosphate resorbing area using incubator‐facilitated and video‐enhanced microscopy
Authors: Morimoto Yoshitaka , Hoshino Hironobu , Sakurai Takashi , Terakawa Susumu , Nagano Akira
Published: November 2008

Quantitative evaluation of the ability of bone resorption activity in live osteoclast‐like cells (OCLs) has not yet been reported on. In this study, we observed the sequential morphological change of OCLs and measured the resorbing calcium phosphate (CP) area made by OCLs alone and with the addition of elcatonin utilizing incubator facilitated video‐enhanced microscopy. OCLs, which were obtained from a coculture of ddy‐mouse osteoblastic cells and bone marrow cells, were cultured on CP‐coated quartz cover slips. The CP‐free area increased constantly in the OCLs alone, whereas it did not increase after the addition of elcatonin. This study showed that analysis of the resorbed areas under the OCL body using this method enables the sequential quantitative evaluation of the bone resorption activity and the effect of several therapeutic agents on bone resorption in vitro. Microsc. Res. Tech, 2009. © 2008 Wiley‐Liss, Inc.
Thermo‐Raman spectroscopy of selected layered double hydroxides of formula Cu6Al2(OH)16CO3 and Zn6Al2(OH)16CO3
Authors: Frost Ray L. , Soisnard Aurore , Voyer Nicolas , Palmer Sara J. , Martens Wayde N.
Published: November 2008

Raman spectroscopy using a hot stage was used to characterise layered double hydroxides (LDHs) of the formula (Cu,Zn)6Al2(OH)16(CO3)·4H2O. The spectra were used to assess the molecular assembly of the cations in the LDH structure. The sharp band at 1058 cm−1for the Zn6Al2(OH)16(CO3)·4H2O is assigned to the ν1CO32− symmetric stretching mode. This band shifts to higher wavenumbers and is observed at 1103 cm−1at 600 °C. It is proposed that metal carbonate species formed during the decomposition of the hydrotalcite structure is responsible for the increase in the band position. The Cu–Al hydrotalcite did not show the same trend. The symmetric stretching mode of carbonate is observed at around 1110 cm−1, and at temperatures above 200 °C a shoulder appears at around 1210 cm−1, suggested to be due to CuCO3. Copyright © 2008 John Wiley & Sons, Ltd.
Raman spectroscopic study of the magnesium‐carbonate minerals—artinite and dypingite
Authors: Frost Ray L. , Bahfenne Silmarilly , Graham Jessica
Published: November 2008

Magnesium minerals are important in the understanding of the concept of geosequestration. The two hydrated hydroxy magnesium‐carbonate minerals artinite and dypingite were studied by Raman spectroscopy. Intense bands are observed at 1092 cm−1 for artinite and at 1120 cm−1 for dypingite, attributed ν1 symmetric stretching mode of CO32−. The ν3 antisymmetric stretching vibrations of CO32− are extremely weak and are observed at 1412 and 1465 cm−1 for artinite and at 1366, 1447 and 1524 cm−1 for dypingite. Very weak Raman bands at 790 cm−1 for artinite and 800 cm−1 for dypingite are assigned to the CO32−ν2 out‐of‐plane bend. The Raman band at 700 cm−1 of artinite and at 725 and 760 cm−1 of dypingite are ascribed to CO32−ν2 in‐plane bending mode. The Raman spectrum of artinite in the OH stretching region is characterised by two sets of bands: (1) an intense band at 3593 cm−1 assigned to the MgOH stretching vibrations and (2) the broad profile of overlapping bands at 3030 and 3229 cm−1 attributed to water stretching vibrations. X‐ray diffraction studies show that the minerals are disordered. This is reflected in the difficulty of obtaining Raman spectra of reasonable quality, and explains why the Raman spectra of these minerals have not been previously or sufficiently described. Copyright © 2008 John Wiley & Sons, Ltd.
Enhancement of analyte detectability in isotachophoresis exploiting spectrophotometric diode‐array detection with chemometric data processing
Authors: Strašík Stanislav , Lučaníková Mária , Kaniansky Dušan
Published: November 2008

The potentialities of capillary ITP combined with diode‐array detection (DAD) with subsequent chemometric data processing have been investigated in this work. A series of different migration configurations were created using model analytes, interferents and appropriate spacers. Special attention has been paid not only to constituents migrating in fully developed ITP zones but also to the spike mode of ITP migration. The purity assessment and identity confirmation of model analytes migrating in both modes were performed by means of multivariate curve resolution and target transformation factor analysis (TTFA). Their successful applications have revealed a smart way to increase in the analytical information obtained by ITP separation even in the instance of trace analysis.
Overloaded elution band profiles of ionizable compounds in reversed‐phase liquid chromatography: Influence of the competition between the neutral and the ionic species
Authors: Gritti Fabrice , Guiochon Georges
Published: November 2008

The parameters that affect the shape of the band profiles of acido‐basic compounds under moderately overloaded conditions (sample size less than 500 nmol for a conventional column) in RPLC are discussed. Only analytes that have a single pKa are considered. In the buffer mobile phase used for their elution, their dissociation may, under certain conditions, cause a significant pH perturbation during the passage of the band. Two consecutive injections (3.3 and 10 μL) of each one of three sample solutions (0.5, 5, and 50 mM) of ten compounds were injected on five C18‐bonded packing materials, including the 5 μm Xterra‐C18 (121 Å), 5 μm Gemini‐C18 (110 Å), 5 μm Luna‐C18(2) (93 Å), 3.5 μm Extend‐C18 (80 Å), and 2.7 μm Halo‐C18 (90 Å). The mobile phase was an aqueous solution of methanol buffered at a constant WWpH of 6, with a phosphate buffer. The total concentration of the phosphate groups was constant at 50 mM. The methanol concentration was adjusted to keep all the retention factors between 1 and 10. The compounds injected were phenol, caffeine, 3‐phenyl 1‐propanol, 2‐phenyl butyric acid, amphetamine, aniline, benzylamine, p‐toluidine, procainamidium chloride, and propranololium chloride. Depending on the relative values of the analyte pKa and the buffer solution pH, these analytes elute as the neutral, the cationic, or the anionic species. The influence of structural parameters such as the charge, the size, and the hydrophobicity of the analytes on the shape of its overloaded band profile is discussed. Simple but general rules predict these shapes. An original adsorption model is proposed that accounts for the unusual peak shapes observed when the analyte is partially dissociated in the buffer solution during its elution.
Sustainable tourism rapid indicators for less‐developed islands: an economic perspective
Authors: Reddy Maharaj Vijay
Published: November 2008

Research on the aspects of tourism and sustainability is growing with a concern that sustainable tourism principles are difficult to implement in developing countries. Within this context, the paper has engaged in the identification, selection and evaluation of sustainability indicators for rapid assessment of tourism development in one of the remotest and most sensitive destinations in the world, the Andaman and Nicobar Islands of India (ANI). It reviews the indicator sets and research on indicator development frameworks and examines the identification and assessment of rapid economic indicators for the ANI. The ANI indicator development strategy considered indicators that are developed and assessed mainly for developed countries and evaluated a feasible bottom‐up approach, which is mainly based on local knowledge for sustainable tourism initiatives in less‐developed islands. Copyright © 2008 John Wiley & Sons, Ltd.
Accelerated corrosion tests in the automotive industry: A comparison of the performance towards cosmetic corrosion
Authors: LeBozec N. , Blandin N. , Thierry D.
Published: November 2008

Corrosion resistance is an important property requirement for materials used in the manufacturing of automobiles, particularly for vehicles that operate on roads treated with de‐icing salt. This implies to test the corrosion resistance of automotive systems, in order to make a good selection of materials. Field‐tests, including stationary and mobile exposures are normally the most reliable ways of doing this, but they are costly and time consuming, as 2–8 years exposure is generally needed for a full assessment of the corrosion resistance. Since, the use of the standard neutral salt spray test, which is well known to give a poor correlation with field data, a large development in the testing procedures has occurred with the use of cyclic corrosion tests, which alternate between pollution phase and wet/dry periods. Today, there are indeed as many accelerated corrosion tests as automotive manufacturers, which are currently used in order to develop and qualify new products against corrosion, to develop new protective coating systems and select materials. In the present work, steel‐ and zinc‐coated materials in cosmetic and crevice configuration were exposed in a large number of accelerated corrosion tests in the automotive industry. From the study, it was shown that the results and consequently the prediction on the lifetime of the same material were very much dependent on which accelerated corrosion test was used. The results were explained in terms of different salt loads applied in the different tests.
Synthesis of Poly(vinyl acetate) Nanogels by Xanthate‐Mediated Radical Crosslinking Copolymerization
Authors: Poly Julien , Wilson D. James , Destarac Mathias , Taton Daniel
Published: November 2008

Poly(vinyl acetate) (PVAc) nanogels are synthesized by a radical crosslinking copolymerization (RCC) in solution of vinyl acetate and divinyl adipate (DVA) or 2,4,6‐tris(allyloxy)‐1,3,5‐triazine (TAT) as the crosslinker, in the presence of a xanthate as a reversible chain transfer agent. Higher concentrations of crosslinker and lower concentrations of xanthate produce PVAc nanogels of higher molar masses, for a given concentration of xanthate and for a fixed concentration of crosslinker, respectively. The xanthate end‐groups allow for the synthesis of ‘second generation’ nanogels through a subsequent RCC from precursors. The chemical cleavage of the crosslinks yields individual poly(vinyl alcohol) chains, which attests that the length of the constitutive chains is controlled by the xanthate.

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Poly(L‐lactide) Nano‐ and Microfibers by Electrospinning: Influence of Poly(L‐lactide) Molecular Weight
Authors: Tomaszewski Waclaw , Duda Andrzej , Szadkowski Marek , Libiszowski Jan , Ciechanska Danuta
Published: November 2008

Summary: The electrospinning technique based on single and multi‐jet systems was applied for poly(L‐lactide) (PLA) nano‐ and microfibers as well as fibrous mats manufacture; the latter with dimensions suitable for the tensile tests. The PLA's employed were prepared by the controlled ring‐opening polymerization of the L,L‐lactide (LA) monomer. The resulting fibers thickness was correlated with molecular weights of PLA's and viscosities of spinning solutions. The scanning electron microscopic, thermal, and tensile characteristics of the polymeric materials and fibrous mats were also examined.
Biodegradation of Blown Films Based on Poly(lactic acid) under Natural Conditions
Authors: Sedlarik Vladimir , Saha Nabanita , Sedlarikova Jana , Saha Petr
Published: November 2008

Summary: Commercially available polymer Bioflex® 219F, blend of polylactic acid and biodegradable co‐polyester, was used for film preparation, performed on mono‐extrusion blown moulding machine. Resulting thin film was investigated on biodegradability in composting conditions for 6 weeks. The influence of microbial attack on mechanical, physico‐chemical properties, weight loss and surface morphology was tested weekly. The results obtained during 6 weeks of composting indicate relatively good accessibility to biological degradation. Moreover, the time course of studied properties was observed through the test period.
Geometry update driven by material forces for simulation of brittle crack growth in functionally graded materials
Authors: Mahnken Rolf
Published: November 2008

Functionally graded materials (FGMs) are advanced materials that possess continuously graded properties, such that the growth of cracks is strongly dependent on the gradation of the material. In this work a thermodynamic consistent framework for crack propagation in FGMs is presented, by applying a dissipation inequality to a time‐dependent migrating control volume. The direction of crack growth is obtained in terms of material forces as a result of the principle of maximum dissipation. In the numerical implementation a staggered algorithm—deformation update for fixed geometry followed by geometry update for fixed deformation—is employed within each time increment. The geometry update is a result of the incremental crack propagation, which is driven by material forces. The corresponding mesh is generated by combining Delaunay triangulation with local mesh refinement. Furthermore a Newton algorithm is proposed, taking into account mesh transfer of displacements for crack propagation in incremental elasticity. In two numerical examples brittle crack propagation in FGMs is investigated for various directions of strength gradation within the structures. Copyright © 2008 John Wiley & Sons, Ltd.
Interface‐reduction for the Craig–Bampton and Rubin method applied to FE–BE coupling with a large fluid–structure interface
Authors: Junge Michael , Brunner Dominik , Becker Jens , Gaul Lothar
Published: November 2008

Component mode‐based model‐order reduction (MOR) methods like the Craig–Bampton method or the Rubin method are known to be limited to structures with small coupling interfaces. This paper investigates two interface‐reduction methods for application of MOR to systems with large coupling interfaces: for the Craig–Bampton method a direct reduction method based on strain energy considerations is investigated. Additionally, for the Rubin method an iterative reduction scheme is proposed, which incrementally constructs the reduction basis. Hereby, attachment modes are tested if they sufficiently enlarge the spanned subspace of the current reduction basis. If so, the m‐orthogonal part is used to augment the basis. The methods are applied to FE–BE coupled systems in order to predict the vibro‐acoustic behavior of structures, which are partly immersed in water. Hereby, a strong coupling scheme is employed, since for dense fluids the feedback of the acoustic pressure onto the structure is not negligible. For two example structures, the efficiency of the reduction methods with respect to numerical effort, memory consumption and computation time is compared with the exact full‐order solution. Copyright © 2008 John Wiley & Sons, Ltd.
A discontinuous Galerkin formulation of non‐linear Kirchhoff–Love shells
Authors: Noels L.
Published: November 2008

Discontinuous Galerkin (DG) methods provide a means of weakly enforcing the continuity of the unknown‐field derivatives and have particular appeal in problems involving high‐order derivatives. This feature has previously been successfully exploited (Comput. Methods Appl. Mech. Eng. 2008; 197:2901–2929) to develop a formulation of linear Kirchhoff–Love shells considering only the membrane and bending responses. In this proposed one‐field method—the displacements are the only unknowns, while the displacement field is continuous, the continuity in the displacement derivative between two elements is weakly enforced by recourse to a DG formulation. It is the purpose of the present paper to extend this formulation to finite deformations and non‐linear elastic behaviors. While the initial linear formulation was relying on the direct linear computation of the effective membrane stress and effective bending couple‐stress from the displacement field at the mid‐surface of the shell, the non‐linear formulation considered implies the evaluation of the general stress tensor across the shell thickness, leading to a reformulation of the internal forces of the shell. Nevertheless, since the interface terms resulting from the discontinuous Galerkin method involve only the resultant couple‐stress at the edges of the shells, the extension to non‐linear deformations is straightforward. Copyright © 2008 John Wiley & Sons, Ltd.
Epithelial–mesenchymal transition induced by biliary innate immunity contributes to the sclerosing cholangiopathy of biliary atresia
Authors: Harada Kenichi , Sato Yasunori , Ikeda Hiroko , Isse Kumiko , Ozaki Satoru , Enomae Mio , Ohama Kazunori , Katayanagi Kazuyoshi , Kurumaya Hiroshi , Matsui Akira , Nakanuma Yasuni
Published: November 2008

Infections of Reoviridae consisting of a double‐stranded RNA (dsRNA) genome and the biliary innate immune response to dsRNA are implicated in the aetiopathogenesis of biliary atresia (BA). Epithelial–mesenchymal transition (EMT) has recently been proposed as a mechanism behind the sclerosing cholangitis in BA. We hypothesized that the innate immune response to dsRNA in biliary epithelial cells plays an important role in peribiliary fibrosis via biliary EMT. Experiments using cultured human biliary epithelial cells revealed that stimulation with poly(I : C) (a synthetic analogue of viral dsRNA) increased the expression of basic fibroblast growth factor (bFGF, an EMT‐inducer), S100A4 (a mesenchymal marker) and Snail (a transcriptional factor), and decreased that of epithelial markers (biliary‐type cytokeratin 19 and E‐cadherin) and Bambi (TGF‐β1 pseudoreceptor). The expression of TGF‐β1 (EMT‐inducer) and vimentin (a mesenchymal marker) was not affected by poly(I : C). Both EMT‐inducers, bFGF and TGF‐β1, evoked a decrease and increase in the expression of the epithelial markers and of vimentin respectively, and the expression of Bambi was down‐regulated on stimulation with bFGF. Combined treatment with bFGF and TGF‐β1 quickly and completely induced a transformation of morphology as well as change from epithelial to mesenchymal features in cultured biliary epithelial cells. Immunohistochemistry revealed that biliary epithelial cells lining extrahepatic bile ducts and peribiliary glands in BA frequently show a lack of epithelial markers and an aberrant expression of vimentin. Moreover, the biliary epithelium showing sclerosing cholangitis expressed bFGF accompanied by bFGF‐positive mononuclear cells. In conclusion, the EMT may contribute to the histogenesis of sclerosing cholangiopathy, and the biliary innate immune response to dsRNA viruses induces biliary epithelial cells to undergo EMT via the production of bFGF and the increased susceptibility to TGF‐β1 caused by the down‐regulation of Bambi expression. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Over‐expression of metallothionein predicts chemoresistance in breast cancer
Authors: Yap Xinli , Tan Hong‐Yong , Huang Jingxiang , Lai Yiyang , Yip George Wai‐Cheong , Tan Puay‐Hoon , Bay Boon‐Huat
Published: November 2008

Metallothionein (MT) plays a role in fundamental cellular processes such as proliferation, apoptosis and differentiation. We examined MT expression in women with invasive breast ductal carcinoma who underwent mastectomy/lumpectomy without neo‐adjuvant treatment. We showed that MT was over‐expressed in 87.9% of breast cancer tissues examined, with the mean percentage of positive cells at 30%. There were two patterns of MT expression: predominantly cytoplasmic in 75.9% and nuclear in 24.1% of MT‐positive cases. Higher MT scores were associated with poorer histological grade (p = 0.009) but were independent of age, tumour size and oestrogen receptor status. For patients who were treated with adjuvant chemotherapy (cyclophosphamide/methotrexate/5 fluorouracil‐ or doxorubicin‐based regimes), those with high MT expression had a significantly lower recurrence‐free survival (p = 0.048), suggesting a role of MT in predicting disease recurrence. Down‐regulation of MT in MCF‐7 cells by silencing the MT‐2A gene (the most abundantly expressed of the 10 known functional MT isoforms) increased chemosensitivity of the cells to doxorubicin. To examine the mechanisms underlying these clinical data, we used siRNAs to decrease MT‐2A mRNA expression and protein expression. In MT down‐regulated cells challenged with the IC50 concentration of doxorubicin, we observed a significant reduction in cell viability. Cell cycle analysis also revealed a corresponding increase in apoptosis in the MT down‐regulated cells following doxorubicin exposure, showing that down‐regulation of MT increased susceptibility to doxorubicin cytotoxicity. The data suggest that MT could be a potential marker of chemoresistance and a molecular therapeutic target. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.