bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and self assembly of eosin functionalized amphiphilic block‐random copolymers prepared by ring opening metathesis polymerization
Authors: Sandholzer Martina , Fritz‐Popovski Gerhard , Slugovc Christian 
Published: December 2007

AbstractSelf assembly of block copolymers has gained considerable attention because of its potential use in various areas such as medical and biomedical applications, nanotechnology, and electronics. Herein, we present the synthesis and characterization of amphiphilic block‐random copolymers with a covalently incorporated pH‐sensitive dye, namely eosin. Ring opening metathesis polymerization was chosen for the preparation of well defined block copolymers and block‐random copolymers using a modified “2nd Generation Grubbs” initiator. The self assembly behavior of the block‐random copolymers in solution was studied by dynamic light scattering and small angle X‐ray scattering (SAXS). The influence of dye incorporation on the result of the self assembly process in methanol and ethanol was investigated and a subtle interplay of the nature of the selective solvent, the chain‐length of the block copolymer and the position of the dye within the polymer chain was established. Structural investigations using SAXS revealed a spherical shape and a core‐shell structure of exemplary block and block‐random copolymer micelles. UV–vis absorption and photoluminescence measurements revealed similar optical properties for polymer micelles in methanol compared to polymer solutions in THF. The pH‐sensitive behavior of the eosin dye was preserved within the micelles. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 401–413, 2008
Synthesis, characterization, and properties of new thermally curable polyetheresters containing benzoxazine moieties in the main chain
Authors: Kiskan Baris , Yagci Yusuf , Ishida Hatsuo 
Published: December 2007

AbstractHigh molecular weight polyetheresters (PEE) containing thermally curable benzoxazine units in the main chain have been synthesized. For this purpose, first the diol functional monomer is synthesized through the Mannich reaction of 4,4′‐isopropylidenediphenol (bisphenol A), formaldehyde, and 2‐(2‐aminoethoxy)ethanol. Polycondensation of the resulting benzoxazine dietherdiol with adipoyl chloride and terephthaloyl dichloride in the presence of triethyl amine yields the corresponding PEE with the molecular weights of 34.000 Da. The structures of the precursor diol monomer and the resulting PEEs are confirmed by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy (1H‐NMR) analysis. Curing behavior of both the monomer and polymers has also been studied by differential scanning calorimetry (DSC). Flexible free standing transparent films of the PEEs are obtained by solvent casting from dichloromethane solution on Teflon plates. The films preserve shape and, to some extent, toughness after thermal curing between 140 and 220 °C. Thermal properties of the cured polymers are also investigated by thermogravimetric analysis (TGA). © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 414–420, 2008
Synthesis of triblock copolymers from glycolysed poly(ethylene terephthalate) by living radical polymerization
Authors: Colomines Gael , Otazaghine Belkacem , Boyer Cyrille , Monge Sophie , Robin Jean‐Jacques 
Published: December 2007

AbstractValorization of poly(ethylene terephthalate) (PET) waste has been achieved using glycolysis. The resulting diols were employed for the synthesis of triblock copolymers by atom transfer radical polymerization using copper (I) bromide and (1,1,4,7,10,10)‐hexamethyltriethylenetetramine as catalyst system. Macroinitiator was obtained after depolymerization of PET waste followed by functionalization of the obtained glycolysate with 2‐bromoisobutyrate bromide. Polymerization of styrene (S) and glycidyl methacrylate (GMA) has been achieved leading to PS‐b‐PETG‐b‐PS and (PS‐stat‐PGMA)‐b‐PETG‐b‐(PS‐stat‐PGMA) triblock copolymers. Best results were obtained at 100 °C. At this temperature, termination reaction were negligible and the measured number‐average molar mass of the product increased linearly with monomer conversion in agreement with the theoretical Mn with low polydispersity products achieved. Polymers were also characterized by 1H NMR. This work presents a original valorization of PET waste as (PS‐stat‐PGMA)‐b‐PETG‐b‐(PS‐stat‐PGMA) copolymer could be used as heat curable coatings. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 433–443, 2008
Molecular design of efficient white‐light‐emitting fluorene‐based copolymers by mixing singlet and triplet emission
Authors: Xu Yunhua , Guan Rong , Jiang Jiaxing , Yang Wei , Zhen Hongyu , Peng Junbiao , Cao Yong 
Published: December 2007

AbstractA new strategy to realize efficient white‐light emission from a binary fluorene‐based copolymer (PF‐Phq) with the fluorene segment as a blue emitter and the iridium complex, 9‐iridium(III)bis(2‐(2‐phenyl‐quinoline‐N,C3′)(11,13‐tetradecanedionate))‐3,6‐carbazole (Phq), as a red emitter has been proposed and demonstrated. The photo‐ and electroluminescence properties of the PF‐Phq copolymers were investigated. White‐light emission with two bands of blue and red was achieved from the binary copolymers. The efficiency increased with increasing concentration of iridium complex, which resulted from its efficient phosphorescence emission and the weak phosphorescent quenching due to its lower triplet energy level than that of polyfluorene. In comparison with the binary copolymer, the efficiency and color purity of the ternary copolymers (PF‐Phq‐BT) were improved by introducing fluorescent green benzothiadiazole (BT) unit into polyfluorene backbone. This was ascribed to the exciton confinement of the benzothiadiazole unit, which allowed efficient singlet energy transfer from fluorene segment to BT unit and avoided the triplet quenching resulted from the higher triplet energy levels of phosphorescent green emitters than that of polyfluorene. The phosphorescence quenching is a key factor in the design of white light‐emitting polyfluorene with triplet emitter. It is shown that using singlet green and triplet red emitters is an efficient approach to reduce and even avoid the phosphorescence quenching in the fluorene‐based copolymers. The strategy to incorporate singlet green emitter to polyfluorene backbone and to attach triplet red species to the side chain is promising for white polymer light‐emitting diodes. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 453–463, 2008
Effect of molecular architecture and size of mesogen on phase behavior and photoactive properties of photoactive liquid crystalline hyperbranched polyester epoxies containing benzylidene moiety
Authors: Srinivasa Rao V. , Samui A. B. 
Published: December 2007

AbstractA series of photoactive liquid crystalline linear and hyperbranched polyester epoxies were synthesized by polyaddition of photoactive bis benzylidene alkanone diol monomers and terephthalic acid and trimesic acid respectively with good yield. The effect of molecular architecture (linear and hyperbranched), size of mesogenic unit (cyclic and acyclic units) on the physicochemical, thermal, mesogenic, and photoactive properties of hyperbranched polymers were studied and compared. Degree of branching of hyperbranched polymers was found to be in the range of 0.46–0.49. Monomers containing cyclic moieties only exhibited nematic mesophase, while all polymers exhibited typical nematic mesophase. Intermolecular photo cycloaddition reaction was studied by ultraviolet–visible spectra (UV–vis) and NMR spectroscopy and photo viscosity measurement of UV irradiated polymer solutions. Faster photo induced behavior of hyperbranched polymers containing acyclic alkanone moiety, as compared to polymers containing cycloalkanone moieties, was observed. The change in the refractive index was found to be in the range of 0.02–0.024. Substantial variation of refractive index indicates that this polymer could be used for optical recording. All the polymers were also found to be fluorescent in nature. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 552–563, 2008
Proteomic characterization of Sophoraflavone J‐induced apoptosis in HepG2 cells
Authors: Cheung Crystal Sao‐Fong , Hon Po‐Ming , Fung Kwok‐Pui , Au Shannon Wing‐Ngor 
Published: December 2007

AbstractChinese herb Radix sophorae is widely applied as an anticarcinogenic/antimetastatic agent against liver cancers. In the current study, Sophoraflavone J, a flavonoid constituent enriched in the root of Radix sophorae, induced apoptosis in human hepatoma HepG2 cells via the intrinsic mitochondrial death pathway. The molecular mechanism of the cytotoxic effect was further investigated by a comparative proteomic approach. Differentially expressed proteins identified included membrane proteins/antigens, structural proteins, transcriptional factors, glycolytic enzymes, heat‐shock chaperon proteins, ROS‐related proteins and proteosomes, etc. These findings were further validated by Western blot analysis and real‐time PCR. Preliminary experiments to characterize the roles of these proteins were conducted. Our data suggested that Sophoraflavone J treatment triggered nutrient depletion and generation of ROS in cells, which subsequently led to mitochondrial dysfunction and apoptosis.
Apolipoprotein A1: A new serum marker correlated to JAK2 V617F proportion at diagnosis in patients with polycythemia vera
Authors: Mossuz Pascal , Bouamrani Ali , Brugière Sabine , Arlotto Marie , Hermouet Sylvie , Lippert Eric , Laporte François , Girodon François , Dobo Irène , Vincent Praloran , Garin Jérome , Cahn Jean Yves , Berger François 
Published: December 2007

AbstractPolycythemia vera (PV) is a myeloproliferative disorder (MPD) characterized by an acquired gain‐of‐function mutation of the JAK2 protein (JAK2 V617F). Allele‐specific quantitative PCR has showed a JAK2 V617F dosage effect on haematological and clinical parameters of PV at diagnosis, but it is unknown whether the level of certain serum proteins might correlate with the proportion of mutated JAK2. Taking into account that such proteins could represent useful prognostic marker, we investigated the serum protein profile of PV patients by SELDI‐TOF MS. We identified apolipoprotein A1 (Apo‐A1) as a serum marker correlated to the percentage of JAK2 V617F alleles; Apo‐A1 expression being the highest for PV patients with more than 75% of mutated alleles. Immuno‐assay on an automated random immuno‐analyser confirmed the correlation between Apo‐A1 concentrations and JAK2 V617F percentages, and showed that serum Apo‐A1 assay allowed the specific discrimination of PV patients with high levels of mutated alleles (≥75%). These data suggest that Apo‐A1 assay could be a useful assay for the stratification of PV patients at diagnosis.
Utilizing endoscopic technology to reveal real‐time proteomic alterations in response to chemoprevention
Authors: Nakanishi Masako , Ménoret Antoine , Belinsky Glenn S. , Giardina Charles , Godman Cassandra A. , Vella Anthony T. , Rosenberg Daniel W. 
Published: December 2007

AbstractCancer chemoprevention approaches use either pharmacological or dietary agents to impede, arrest or reverse the carcinogenic process. Although several agents have shown effectiveness against colon cancer, present intervention strategies provide only partial reduction. In this study, we utilized high‐resolution endoscopy to obtain colon tumor biopsy specimens from Apc mutant mice before and after 2‐wk sulindac intervention. To acquire information beyond genomics, proteome analysis using the ProteomeLab PF2D platform was implemented to generate 2‐D protein expression maps from biopsies. Chromatograms produced common signature profiles between sulindac and nonsulindac treated samples, and contrasting profiles termed “fingerprints”. We selected a double peak that appeared in tumor biopsies from sulindac‐treated mice. Further analyses using MS sequencing identified this protein as histone H2B. The location of H2B in the 1st dimension strongly suggested PTM, consistent with identification of two oxidized methionines. While further studies on sulindac proteomic fingerprints are underway, this study demonstrates the feasibility and advantages of “real‐time” proteomic analysis for obtaining information on biomarker discovery and drug activity that would not be revealed by a genetic assay. This approach should be broadly applicable for assessing lesion responsiveness in a wide range of translational and human clinical studies.
Pharmacological studies on hypotensive, diuretic and vasodilator activities of chrysin glucoside from Calycotome villosa in rats
Authors: Cherkaoui‐Tangi K. , Lachkar M. , Wibo M. , Morel N. , Gilani A. H. , Lyoussi B. 
Published: December 2007

AbstractThe present study was undertaken in normotensive anaesthetized male rats that received a continuous perfusion of a chrysin glucoside isolated from the flowers and leaves of Calycotome villosa subsp intermedia at a dose of 2.5 mg/kg, or furosemide (control diuretic) at a dose of 0.5 mg/kg. Compared with the control rats receiving NaCl (0.9%), the urine flow, glomerular filtration and electrolyte excretion (Na+, K+) increased significantly in rats treated with chrysin glucoside (p < 0.001). A similar effect was observed in the rats perfused with furosemide. Intravenous injections of bolus doses (1–3 mg/kg) of the chrysin glucoside to anaesthetized rats elicited an immediate and dose‐dependent decrease in mean arterial blood pressure (MABP). Pretreatment of the rats with the nitric oxide synthase inhibitor, l‐NOArg (10 mg/kg), reduced partially, but significantly (p < 0.01), the maximal decrease in MABP elicited by chrysin glucoside. In the rat isolated aorta preparation, chrysin glucoside (10–100 µm) inhibited in a concentration‐dependent manner the noradrenaline (1 µm) induced contractions (IC50 = 52 µm). This relaxant activity of chrysin glucoside was significantly reduced by incubation of the endothelium‐intact rings with l‐NOArg (100 µm), (80 ± 4.7% vs 48 ± 5.06% in the absence of l‐NOArg). In conclusion, these results demonstrate a diuretic and hypotensive action of a chrysin glucoside from Calycotome villosa in anaesthetized rats and indicating an action on renal function, and an active vascular relaxation mediated partially through nitric oxide release. Copyright © 2007 John Wiley & Sons, Ltd.
Cardioprotective effects of Astragali Radix against isoproterenol‐induced myocardial injury in rats and its possible mechanism
Authors: Xu Xiao‐Le , Ji Hui , Gu Shu‐Yi , Shao Qin , Huang Qiu‐Ju , Cheng Yan‐Ping 
Published: December 2007

AbstractThe purpose of the present study was to investigate the effects of the Chinese medical herb Astragali Radix on myocardial injury in vivo and its possible mechanisms. Myocardial injury in rats was induced by the subcutaneous injection of a high dose of isoproterenol for 10 days, and the therapeutic effects of Astragali Radix were observed. Cardiac hemodynamics, heart coefficient and marker enzymes in serum showed that Astragali Radix prevented isoproterenol‐induced myocardial damage. Astragali Radix also improved the antioxidant status by decreasing the lipid peroxidative product malondialdehyde and increasing the activity of the antioxidant enzyme superoxide dismutase. The observed depressions in sarcoplasmic reticulum Ca2+‐ATPase mRNA and protein expression as well as Ser16‐phosphorylated phospholamban protein expression in isoproterenol‐treated rats were attenuated by Astragali Radix treatment. Moreover, treatment with Astragali Radix showed higher myocardial cAMP content compared with the isoproterenol‐alone group. These results suggest that the antioxidant property and partial prevention of changes in protein and gene expression of cardiac sarcoplasmic reticulum Ca2+ regulatory proteins which may be mediated through the cAMP pathway could help to explain the beneficial effects of Astragali Radix on myocardial injury in vivo. Copyright © 2007 John Wiley & Sons, Ltd.
Comparison of negative ion electrospray mass spectra measured by seven tandem mass analyzers towards library formation
Authors: Volná Kateřina , Holčapek Michal , Kolářová Lenka , Lemr Karel , Čáslavský Josef , Kačer Petr , Poustka Jan , Hubálek Martin 
Published: December 2007

AbstractA library of negative ion electrospray ionization mass spectra and tandem mass spectra (MS/MS) of sulfonated dyes has been developed for fast identification purposes. The uniform protocol has been elaborated and applied to the measurements of more than 50 anionic dyes. Three collision energies are selected in our protocol which ensures that at least one of them provides a suitable ratio of product ions to the precursor ion. The robustness is investigated with altered values of tuning parameters (e.g. the pressure of the nebulizing gas, the temperature and the flow rate of drying gas, and the mobile phase composition). The results of the inter‐laboratory comparison of product ion mass spectra recorded on seven different tandem mass spectrometers (three ion traps, two triple quadrupoles and two hybrid quadrupole time of flight instruments) are presented for four representative anionic dyes – azo dye Acid Red 118, anthraquinone dye Acid Violet 43, triphenylmethane dye Acid Blue 1 and Al(III) metal‐complex azo dye. The fragmentation patterns are almost identical for all tandem mass analyzers, only the ratios of product ions differ somewhat which confirms the possibility of spectra transfer among different mass analyzers with the goal of library formation. Copyright © 2007 John Wiley & Sons, Ltd.
Simulation of generation times of the rusty grain beetle, Cryptolestes ferrugineus, in farm‐stored grain in the canadian prairies, 1952‐1990
Authors: Woods S. M. , White N. D. G. , Sinha R. N. 
Published: December 2007

AbstractThe number of potential annual generations of the rusty grain beetle, Cryptolestes ferrugineus, was simulated in wheat stored in granaries for all crop districts in the prairie provinces of Canada each year from 1952 to 1990 using a population dynamic model driven by ecological variables. Granary size was assumed to be 6 m in diameter. Historical data for temperatures at harvest and times when storage began were used in the simulation model. A second model, which predicted the rate of temperature change at the centre of a 6‐m‐diameter bulk of wheat, determined environmental parameters for the population dynamic model. (Grain moisture content was assumed constant at 14.5% wet mass basis.) The combined model shows that the initial storage temperature is the most important factor responsible for predicting the number of generations and levels of infestation of C. ferrugineus. This finding was largely validated by historical grain storage and infestation data. For various years initial grain temperature ranged from 17.7 to 37.4 °C and harvest dates were between 1 August and 20 October. The number of generations annually in simulations based on field conditions ranged from 0.35 to 6.77 with a mean of 3.29. Three or more generations result in a severe infestation and every year at least three simulated generations were completed in some crop districts. In one year, at least three generations were completed in every crop district. Harvest temperature and date permit prediction of crop districts that will potentially have the largest populations of C. ferrugineus so that early monitoring of wheat for infestations can be targeted to areas most at risk.
Iron status markers in nonanemic pregnant women with and without iron supplementation
Authors: Ziaei Saeideh , Mehrnia Maryam , Faghihzadeh Soghrate 
Published: December 2007

AbstractObjectiveTo measure levels of markers of anemia before and after delivery in women who had high hemoglobin levels during the early stage of the second trimester of pregnancy and did not receive iron supplementation during their pregnancies.MethodsIn a randomized, double‐blind, placebo‐controlled trial 244 women who had a hemoglobin concentration of 13.2 g/dL or greater and a serum ferritin level higher than 15 μg/L between the 13th and 18th week of pregnancy took either one 150‐mg tablet of ferrous sulfate daily or placebo during their pregnancies. Markers of anemia were measured at the time of delivery and 6 weeks postpartum.ResultsThere were statistically significant differences between the 2 groups in hematocrit as well as hemoglobin and ferritin levels both at the time of delivery and 6 weeks postpartum (P < 0.05), but these differences were not clinically significant.ConclusionNot using iron supplementation did not cause a considerable decrease in markers of anemia in women with a hemoglobin concentration of 13.2 g/dL or greater in the second trimester of pregnancy.
The origins and development of institutional welfare support in early modern Württemberg, c.1500–1700
Authors: WARDE PAUL 
Published: December 2007

ABSTRACTThis article examines the development of formal poor-relief provision across the sixteenth and seventeenth centuries in rural Germany, through a case study of a district of the Duchy of Württemberg. It presents a detailed picture of practices to support the poor, whether through payments and alms from the poor chest, institutions providing credit, common rights or village and town granaries. In building up a picture of institutional practice, it also presents extensive information on the recipients of relief. It is argued that both the institutional framework and new trends in its development during the period ante-dated the Reformation, and that this society enjoyed a wide and varied capacity to support the poor that bears comparison with the English Old Poor Law. However, in a differing socio-economic context, demand for support remained more limited, and the demographic catastrophe of the Thirty Years' War arrested trends towards increasingly formalized collections, pensions and doles.
On Manin's conjecture for singular del Pezzo surfaces of degree four, II
Authors: DE LA BRETÈCHE R. , BROWNING T. D. 
Published: December 2007

AbstractThis paper establishes the Manin conjecture for a certain non-split singular del Pezzo surface of degree four$X \subset \bfP^4$. In fact, ifU⊂Xis the open subset formed by deleting the lines fromX, andHis the usual projective height function on$\bfP^4(\Q)$, then the height zeta function$ \sum_{x \in U(\Q)}{H(x)^{-s}} $is analytically continued to the half-plane ℜe(s) > 17/20.
Self-gravitating stationary spherically symmetric systems in relativistic galactic dynamics
Authors: FJÄLLBORG MIKAEL , HEINZLE J. MARK , UGGLA CLAES 
Published: December 2007

AbstractWe study equilibrium states in relativistic galactic dynamics which are described by stationary solutions of the Einstein–Vlasov system for collisionless matter. We recast the equations into a regular three-dimensional system of autonomous first order ordinary differential equations on a bounded state space. Based on a dynamical systems analysis we derive new theorems that guarantee that the steady state solutions have finite radii and masses.
Integral bases for certain TQFT-modules of the torus
Authors: QAZAQZEH KHALED 
Published: December 2007

AbstractWe find two bases for the lattices of the SU(2)-TQFT-theory modules of the torus over given rings of integers. One basis is a variation on the bases defined in [GMW] for the lattices of the SO(3)-TQFT-theory modules of the torus. Moreover, we discuss the quantization functors (Vp, Zp) for p = 1, and p = 2. Then we give concrete bases for the lattices of the modules in the 2-theory. We use the above results to discuss the ideal invariant defined in [FK]. The ideal can be computed for all the 3-manifolds using the 2-theory, and for all 3-manifolds with torus boundary using the SU(2)-TQFT-theory. In fact, we show that this ideal using the SU(2)-TQFT-theory is contained in the product of the ideals using the 2-theory and the SO(3)-TQFT-theory under a certain change of coefficients, and with equality in the case of torus boundary.