bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crystallisation of 1,3‐dipalmitoyl‐2‐oleoylglycerol and tripalmitoylglycerol and their mixtures from acetone
Authors: Smith Kevin W. , Cain Fred W. , Talbot Geoff 
Published: July 2005

AbstractCrystallisation from acetone of 1,3‐dipalmitoyl‐2‐oleoylglycerol (POP), tripalmitoylglycerol (PPP) and their mixtures has been studied at a range of cooling rates, determining the metastable zone width using turbidimetry. A log‐log plot of the cooling rate against the maximum undercooling for POP indicated a relative insensitivity of the metastable zone width to the cooling rate. The PPP metastable zone width demonstrated a slight dependence on concentration. POP crystals were spherulitic, having a more open structure at slower cooling rates. PPP crystals were more plate‐like, producing powdery, more amorphous crystals at high cooling rates. In pure POP systems, onset of crystallisation was quickly followed by rapid crystal growth. The presence of PPP markedly increased the temperature of the onset of crystallisation (by 17 °C at 8% PPP), but the temperature at which crystal growth occurred, although raised, did not increase to the same extent. The clear point of the pure systems was independent of the previous cooling rate, but this was not true in the mixed system, where it decreased with increasing cooling rate. This suggests that a greater proportion of the PPP‐rich phase separates during slower cooling. The morphology of the crystals from the mixed system differed from that in the pure POP system, with just 2% PPP being sufficient to shift the structure to a more lamellar appearance.Keywords: POP, PPP, solubility, supersaturation, undercooling, metastable zone.
Effects of antioxidants on the lipase‐catalyzed acidolysis during production of structured lipids
Authors: Xu Xuebing , Timm‐Heinrich Maike , Nielsen Nina Skall , Porsgaard Trine , Jacobsen Charlotte 
Published: July 2005

AbstractIn the production process of structured lipids, the influence of the addition of antioxidants before enzymatic acidolysis was investigated. Eight different antioxidants were screened: butylated hydroxyanisole, butylated hydroxytoluene, propyl gallate, ascorbyl palmitate, citric acid, EDTA, a tocopherol blend and lecithin. As substrates, oils with different degrees of unsaturation (rapeseed, safflower or fish oil) as well as caprylic and capric acids were used. Enzyme activity (measured as percent incorporation of caprylic/capric acid into the oils) was not significantly influenced by the addition of antioxidants, neither in a batch process nor in a packed‐bed reactor operation. α‐Tocopherol concentrations remained stable for those mixtures where tocopherols were added. Primary oxidation products (measured as peroxide values) were reduced after acidolysis in the packed‐bed reactor, likely due to the adsorption in the enzyme bed. The study shows that the addition of antioxidants before enzymatic reactions has no negative effects on the reaction progress. None of the antioxidants chosen had a significant positive effect on either the reaction process or the oxidative status of the structured lipid produced.
Synthesis and Characterization of Extended Tetrathiafulvalenes with Di‐, Tri‐, and Tetraethynylethene Cores
Authors: Sune Andersson Asbjørn , Qvortrup Katrine , Rossel Torbensen Esben , Mayer Jan‐Philipp , Gisselbrecht Jean‐Paul , Boudon Corinne , Gross Maurice , Kadziola Anders , Kilså Kristine , Brøndsted Nielsen Mogens 
Published: July 2005

AbstractA selection of new acetylenic building blocks has been prepared and employed for construction of extended tetrathiafulvalenes (TTFs) and novel donor–acceptor molecules based on either diethynylethene (DEE), triethynylethene (TriEE), or tetraethynylethene (TEE) cores. The novel chromophores were studied for their redox, chromophoric, and structural properties, which have provided fundamental structure–property relationships. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Protective effects of a mixture of antioxidant vitamins and minerals on the genotoxicity of doxorubicin in somatic cells of Drosophila melanogaster
Authors: Costa Wender Ferreira , Nepomuceno Júlio César 
Published: July 2005

AbstractAntioxidant vitamins are able to deactivate highly bioactive molecules, such as free radicals, that are generated during cellular biochemical processes. Doxorubicin (DXR) is a cancer chemotherapeutic agent that generates free radicals as a byproduct. In the present study, the Drosophila melanogaster somatic wing spot test was used to evaluate the effects of a mixture of vitamins (Vitamins C, E, and β‐carotene) and minerals (copper, selenium, and zinc), commercially known as Vitergan® Zinc Plus, on the genotoxicity of DXR in standard and high‐bioactivation crosses of flies. 12.5, 25, and 50 mg/ml of the vitamin/mineral mixture by itself was nongenotoxic in the trans‐heterozygous descendants of both crosses, while the mixture produced a significant reduction in the genotoxicity produced by 0.125 mg/ml DXR in the trans‐heterozygous descendants of both crosses. The protective effect was observed when the larvae received either pre‐ or cotreatments of the multivitamin/mineral (MV) mixture. The results indicate that, under these experimental conditions, the MV mixture is not genotoxic; however, it protects against the genotoxic effects of the chemotherapeutic free‐radical generator DXR. Environ. Mol. Mutagen., 2006. © 2005 Wiley‐Liss, Inc.
Direct numerical simulation of turbulent forced convection in a pipe
Authors: Piller M. 
Published: July 2005

AbstractDirect numerical simulations (DNS) are carried out to study fully developed turbulent pipe flow and heat transfer at Reynolds number Rem≈5300 based on bulk velocity and pipe diameter. This paper provides detailed information on the mean properties and turbulence statistics up to fourth order, the budget and the wavenumber spectra of the temperature fluctuations, for three different wall boundary conditions. To investigate the differences between fully developed turbulent heat transfer in axisymmetric pipe and plane channel geometry, the present DNS results are compared to those obtained from channel flow simulations. The differences between channel and pipe flow statistics are modest and reveal that the temperature fluctuations in the pipe are slightly more intense. The present results show that the mean temperature profile does not conform to the accepted law of the wall. The boundary conditions affect the turbulence statistics both in the near‐wall and core regions; this observation complements previous studies concerning different flow and heat transfer configurations. Copyright © 2005 John Wiley & Sons, Ltd.
Effects of surface undulations of biphasic calcium phosphate tablets on human osteoblast behavior
Authors: Santos Euler A. dos , Linhares Adriana B. R. , Rossi Alexandre M. , Farina Marcos , Soares Gloria A. 
Published: July 2005

AbstractIn this work, the in vitro behavior of human osteoblast cells on the undulated surfaces of biphasic calcium phosphate tablets was investigated. The tablets were produced by uniaxial pressing with convex cylindrical undulations occupying only half of the surface area; the other half was flat. Chemical and physical characterization was performed by scanning electron microscopy (SEM), atomic force microscopy (AFM), X‐ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). XRD and FTIR analyses revealed the presence of hydroxyapatite (HA) and α‐tricalcium phosphate (α‐TCP) in a well‐defined ratio. Moreover, microtopography, evaluated by SEM and AFM, was similar on the flat region and on that with undulations. However, surface undulations induced different cellular arrangements, confirming the influence of the macrotopography on the cells orientation. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2005
Early apatite deposition and osteoblast growth on plasma‐sprayed dicalcium silicate coating
Authors: Liu Xuanyong , Xie Youtao , Ding Chuanxian , Chu Paul K. 
Published: July 2005

AbstractDicalcium silicate coating was deposited onto a Ti‐6Al‐4V substrate using plasma‐spraying technology. The coating was immersed in simulated body fluid (SBF) for 1, 3, 6, 12, 24, and 48 h to investigate early apatite formation on the coating. Osteoblasts were also seeded onto the surface of the dicalcium silicate coating to evaluate its biocompatibility. Cold field‐emission scanning electron microscopy and energy‐dispersive X‐ray spectrometry were used to evaluate the morphologies and determine the chemical composition of the coatings. The surface structural changes caused by immersion in SBF were analyzed using thin‐film X‐ray diffraction. After the dicalcium silicate coating was soaked in SBF solution 1–6 h, two types of particles containing calcium and phosphorus were formed on the surface. One type consisted of relatively larger particles (P1) precipitated on the surface of the coating from the precursor cluster formed in the SBF solution. The second type was composed of particles (P2) nucleated on the surface of the coating. With increasing immersion time, the particles coalesced to form a surface Ca‐P layer. The Ca‐P layer was composed of amorphous calcium phosphate that was not transformed to crystalline apatite until the immersion time in SBF exceeded 24 h. The formation mechanism of the Ca‐P layer and apatite on the surface of the coating is believed to be involved in the formation of the Si 3‐ring active surface site with negative charge. The cell‐seeding test revealed that osteoblasts grew and proliferated very well on the surface of the dicalcium silicate coating. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2005
Differential levels of dendritic cell maturation on different biomaterials used in combination products
Authors: Babensee Julia E. , Paranjpe Abhijit 
Published: July 2005

AbstractImmature dendritic cells (iDCs) were derived from human peripheral blood monocytes, and treated with films of biomaterials commonly used in combination products (e.g., tissue engineered constructs or vaccines) to assess the resultant dendritic cell (DC) maturation compared to positive control of lipopolysaccharide (LPS) treatment for DC maturation or negative control of untreated iDCs. The following biomaterials were tested: alginate, agarose, chitosan, hyaluronic acid, 75:25 poly(lactic‐co‐glycolic acid) (PLGA). The effect of DC culture on these films was undertaken to identify biomaterials which support DC maturation and those biomaterials that did not. Dendritic cells treated with chitosan or PLGA (agarose to a lesser extent) films increased expression levels of CD86, CD40, and HLA‐DQ, compared to control iDCs, similar to LPS‐matured DCs, whereas DCs treated with alginate or hyaluronic acid films decreased their expression levels of these same molecules. In summary, a differential effect of the biomaterial on which iDCs were cultured was observed as far as the extent of induced DC maturation. The effect of biomaterials on DC maturation, and the associated adjuvant effect, is a novel biocompatibility selection and design criteria for biomaterials to be used in combination products in which immune consequences are potential complications or outcomes. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2005
Scheduling a production–distribution system to optimize the tradeoff between delivery tardiness and distribution cost
Authors: Pundoor Guruprasad , Chen Zhi‐Long 
Published: July 2005

AbstractWe consider a make‐to‐order production–distribution system with one supplier and one or more customers. A set of orders with due dates needs to be processed by the supplier and delivered to the customers upon completion. The supplier can process one order at a time without preemption. Each customer is at a distinct location and only orders from the same customer can be batched together for delivery. Each delivery shipment has a capacity limit and incurs a distribution cost. The problem is to find a joint schedule of order processing at the supplier and order delivery from the supplier to the customers that optimizes an objective function involving the maximum delivery tardiness and the total distribution cost. We first study the solvability of various cases of the problem by either providing an efficient algorithm or proving the intractability of the problem. We then develop a fast heuristic for the general problem. We show that the heuristic is asymptotically optimal as the number of orders goes to infinity. We also evaluate the performance of the heuristic computationally by using lower bounds obtained by a column generation approach. Our results indicate that the heuristic is capable of generating near optimal solutions quickly. Finally, we study the value of production–distribution integration by comparing our integrated approach with two sequential approaches where scheduling decisions for order processing are made first, followed by order delivery decisions, with no or only partial integration of the two decisions. We show that in many cases, the integrated approach performs significantly better than the sequential approaches. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005
MRS assessment of glutamate clearance in a novel masticatory muscle pain model
Authors: Gambarota G. , Philippens M. , Cairns B. E. , Dong X. D. , Renema W. K. J. , Heerschap A. 
Published: July 2005

AbstractThe injection of 1.0 M glutamate into the masseter (jaw‐closer) muscle results in a short period of muscle pain (5–10 min) and a prolonged period of mechanical sensitization (> 30 min). It is unclear, however, whether there is a temporal relationship between intramuscular glutamate concentration and either muscle pain or mechanical sensitization. In the present study, 1H MRS and electrophysiological recording of masticatory muscle nerve fibers were performed in order to monitor glutamate clearance and nerve fiber activity, respectively, after injection of glutamate into rat masticatory muscles. Glutamate signal amplitude was found to decay rapidly (half‐life t½ = 108 ± 42 s), and became indistinguishable from the baseline 10 min after the injection. Glutamate‐evoked nerve fiber activity was also found to decay rapidly (t½ = 76 ± 28 s). These results suggest that glutamate clearance correlates well with the time course of glutamate‐evoked muscle pain fiber discharge. Copyright © 2005 John Wiley & Sons, Ltd.
A relaxation scheme for the approximation of the pressureless Euler equations
Authors: Berthon Christophe , Breuß Michael , Titeux Marc‐Olivier 
Published: July 2005

AbstractIn the present work, we consider the numerical approximation of pressureless gas dynamics in one and two spatial dimensions. Two particular phenomena are of special interest for us, namely δ‐shocks and vacuum states. A relaxation scheme is developed which reliably captures these phenomena. In one space dimension, we prove the validity of several stability criteria, i.e., we show that a maximum principle as well as the TVD property for the discrete velocity component and the validity of discrete entropy inequalities hold. Several numerical tests considering not only the developed first‐order scheme but also a classical MUSCL‐type second‐order extension confirm the reliability and robustness of the relaxation approach. The article extends previous results on the topic: the stability conditions for relaxation methods for the pressureless case are refined, useful properties for the time stepping procedure are established, and two‐dimensional numerical results are presented. © 2005 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2006
Star polymers by ATRP of styrene and acrylates employing multifunctional initiators
Authors: Jankova Katja , Bednarek Melania , Hvilsted Søren 
Published: July 2005

AbstractMultifunctional initiators for atom transfer radical polymerization (ATRP) are prepared by converting ditrimethylolpropane with four hydroxyl groups, dipentaerythritol with six hydroxyl groups, and poly(3‐ethyl‐3‐hydroxymethyl‐oxetane) with ∼11 hydroxyl groups to the corresponding 2‐bromoisobutyrates or 2‐bromopropionates as obtained by reaction with acid bromides. Star polystyrene (PS) is produced by using these macroinitiators and neat styrene in a controlled manner by ATRP at 110 °C, employing the catalytic system CuBr and bipyridine. Mn up to 51,000 associated with narrow molecular weight distributions (PDI < 1.1) are obtained with conversions up to 32%. Hydrolysis of the star‐PS leads to linear chains having the expected Mn values. The star‐PS polymers based on dipentaerythritol degrade thermally in nitrogen in a two‐step process in which the first low‐temperature step involves scission of the ester linkages and the second step corresponds to the normal PS degradation. Star poly(methyl acrylates) with various cores are likewise prepared in a controlled manner by ATRP of methyl acrylate in bulk and in solution at 60–80 °C with the 1,1,4,7,7‐pentamethyldiethylene triamine ligand. Under these conditions, higher conversions were possible still maintaining low PDI signaling controlled star growth. Multiarm stars of poly(n‐butyl acrylate) and poly(n‐hexyl acrylate) with controlled characteristics have also been prepared. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3748–3759, 2005
Fluorinated comblike homopolymers: The effect of spacer lengths on surface properties
Authors: Saïdi Salima , Guittard Frédéric , Guimon Claude , Géribaldi Serge 
Published: July 2005

AbstractA series of polyacrylate monomers with F‐alkylalkyl [F(CF2)n(CH2)n′] side groups were prepared by free‐radical polymerization. The effect of the chemical structure on the surface properties of poly(ethylene terephthalate)s was evaluated by variations in the relative length of the fluorocarbon and hydrocarbon units in the side group. The resulting polymers were quite surface‐active in the solid state. The surface and bulk organization was investigated by X‐ray photoelectron spectroscopy analysis. A strong correlation between the bulk organization and surface properties of the polymers was established. The outmost layer, formed from trifluoromethyl groups and some ester functions, suggests that the side chain is arranged irregularly in the polymer–air interface. The length of the lateral chain governs this organization: long fluorinated chains and short hydrocarbon spacers are essential elements of the molecular design for such low‐surface‐energy materials. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3737–3747, 2005
Synthesis of core‐crosslinked carbosilane block copolymer micelles and their thermal transformation to silicon‐based ceramics nanoparticles
Authors: Matsumoto Kozo , Matsuoka Hideki 
Published: July 2005

AbstractCarbosilane fine particles were synthesized by core‐crosslinking of carbosilane block copolymer micelles and they were pyrolytically transformed into silica nanoparticles. The carbosilane block copolymer, poly(1‐(3‐butenyl)‐1‐methylsilacyclobutane)‐block‐polystyrene, (polyBMSB‐b‐polySt), [(m, n) = (31, 16), (54, 30), and (75, 28)], was synthesized by anionic polymerization of BMSB and St, where m and n represent polymerization degrees of BMSB and St segments, respectively. The block copolymer formed micelles in N,N‐dimethylformamide (DMF). The hydrodynamic diameters (Dh) of the micelles evaluated by dynamic light scattering ranged from 40 to 158 nm depending on the copolymer molecular weight. The core of the micelle was cross‐linked by Pt‐catalyzed hydrosilation with 1,2‐bis(dimethylsilylethane). The Dh of the core‐cross‐linked micelles in THF ranged from 56 to 164 nm. These precursor particles were pyrolyzed at 850 °C under N2 to give ceramic nanoparticles. The diameters of the spherical ceramic particles estimated by AFM ranged from 25 to 60 nm. X‐ray fluorescence analysis of the ceramic products revealed that it consisted of mainly SiO2 rather than SiC. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3778–3787, 2005
Graft copolymerization of poly(styrene‐co‐p‐choloromethylstyrene) with methyl methacrylate and acryloylmorpholine by atom transfer radical polymerization: Graft copolymer characterization and monomer reactivity ratios
Authors: Temüz Mehmet Mürşi̇t , Coşkun Mehmet 
Published: July 2005

AbstractPoly[styrene‐graft‐(acryloylmorpholine‐co‐methyl methacrylate)] graft copolymers in various compositions, poly(styrene‐graft‐acryloylmorpholine), and poly(styrene‐graft‐methyl methacrylate) were prepared by atom transfer radical polymerization with poly(styrene‐co‐p‐chloromethylstyrene) (62/38) as the macroinitiator in the presence of CuBr/1,2‐dipiperidinoethane at 130 °C in N,N‐dimethylformamide. The graft copolymers were characterized by elemental analysis, IR, 1H and 13C NMR, and differential scanning calorimetry. The thermal stabilities of the graft copolymers were investigated by thermogravimetric analysis. The monomer reactivity ratios in the graft copolymerization of acryloylmorpholine (r1) and methyl methacrylate (r2) were calculated by the application of linear methods, such as the Finemann–Ross, inverted Finemann–Ross, Yezrielev–Brokhina–Roskin, Kelen–Tüdos, and extended Kelen–Tüdos methods, and the Mayo–Lewis method, which uses an integrated copolymer equation in a terminal model of copolymerization. r1 was 1.13–2.11, and r2 was 0.49–1.05, according to the various methods. The Yezrielev–Brokhina–Roskin method gave the best linearity for the experimental results, and the r1 and r2 values were 1.28 and 0.54, respectively. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3771–3777, 2005
Dendrimer complexes: Fine control of metal assembly in macromolecules
Authors: Yamamoto Kimihisa 
Published: July 2005

AbstractNew phenylazomethine dendrimers have been developed, with each dendrimer having a unique single structure. From ultraviolet–visible absorption spectra, we determined that stannous chloride added to dendritic polyphenylaz omethine (DPA) was assembled in a stepwise manner from the core shell to the periphery. The selective binding was achieved by the electron density gradient formed in the dendrimer, and it was confirmed by shell‐selective imine reduction, transmission electron microscopy, and NMR measurements. The complex formation constants of the respective shells were estimated to be considerably different by a simulation analysis of ultraviolet–visible absorption spectra. The reversible assembly and release of iron into and out of the dendrimer were possible by electrochemical oxidation and reduction, respectively. DPA with a porphyrin at the core was found to function as an effective reduction catalyst of carbon dioxide. DPA with aryl amine at the core was demonstrated to function as a hole‐transporting material in electroluminescent devices. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3719–3727, 2005