bluuebunny/crossref_metadata_2025 huggingface dataset:
Distribution of Single-Cell Expanded Marrow Derived Progenitors in a Developing Mouse Model of Osteogenesis Imperfecta Following Systemic Transplantation
Authors: Li Feng , Wang Xujun , Niyibizi Christopher
Published: September 2007

We evaluated single-cell-expanded, marrow-derived progenitors for engraftment in a developing mouse model of osteogenesis imperfecta (OI) following systemic transplantation. The present study was initiated to evaluate the potential of mesenchymal stem cells to treat OI. Single-cell-derived progenitors were prepared from marrow stromal cells harvested from normal mice. Selected single-cell-expanded progenitors marked with green fluorescent protein were injected into the neonatal mouse model of OI, and the recipient mice were sacrificed at 2 and 4 weeks following cell transplantation. Examination of the tissues harvested from recipient mice at 2 and 4 weeks after cell transplantation demonstrated that the cells extravasated and engrafted in most of the bones as well as other tissues. Tissue sections made from the tibias and femurs of a selected recipient mouse showed that the cells were distributed in bone marrow, trabecular, and cortical bone as demonstrated by histology and confocal microscopy. The cells that engrafted in the bones of the recipient mouse synthesized and deposited type I collagen composed of α1(I) and α2(I) collagen heterotrimers. Genotyping and gene expression analysis of the cells retrieved from the bones of the recipient mouse at 2 and 4 weeks demonstrated that the cells expressed osteoblast-specific genes, suggesting that the donor cells differentiated into osteoblasts in vivo with no evidence of cell fusion. These data suggest that progenitors infused in developing mice will engraft in various tissues including bones, undergo differentiation, and deposit matrix and form bone in vivo.

Disclosure of potential conflicts of interest is found at the end of this article.
Network‐based fault detection for discrete‐time state‐delay systems: A new measurement model
Authors: He Xiao , Wang Zidong , Ji Y. D. , Zhou D. H.
Published: September 2007

In this paper, the fault detection problem is studied for a class of discrete‐time networked systems with multiple state delays and unknown input. A new measurement model is proposed to account for both the random measurement delays and the stochastic data missing (package dropout) phenomenon, which are typically resulted from the limited capacity of the communication networks. At any time point, one of the following cases (random events) occurs: measurement missing case, no time‐delay case, one‐step delay case, two‐step delay case, …,q‐step delay case. The probabilistic switching between different cases is assumed to obey a homogeneous Markovian chain. We aim to design a fault detection filter such that, for all unknown input and incomplete measurements, the error between the residual and weighted faults is made as small as possible. The addressed fault detection problem is first converted into an auxiliaryH∞filtering problem for a certain Markovian jumping system (MJS). Then, with the help of the bounded real lemma of MJSs, a sufficient condition for the existence of the desired fault detection filter is established in terms of a set of linear matrix inequalities (LMIs). A simulation example is provided to illustrate the effectiveness and applicability of the proposed techniques. Copyright © 2007 John Wiley & Sons, Ltd.
Improvement of the physical properties of poly(methyl methacrylate) by copolymerization with pentafluorophenyl methacrylate
Authors: Tagaya Akihiro , Harada Tomoaki , Koike Koutarou , Koike Yasuhiro , Okamoto Yoshiyuki , Teng Hongxiang , Yang Liang
Published: September 2007

Copolymers of methyl methacrylate (MMA) and pentafluorophenyl methacrylate (PFPMA) of various compositions were prepared with a free‐radical initiator. When PFPMA was included in the copolymers, the glass‐transition temperatures increased and showed a positive deviation from the Gordon–Taylor equation. A copolymer containing 20 wt % PFPMA exhibited almost zero orientational birefringence, and the photoelastic birefringence became zero when the copolymer contained 13 wt % PFPMA. When 20 wt % PFPMA was incorporated into the MMA copolymer, its water absorption decreased to 0.4 wt % versus 1.8 wt % for poly(methyl methacrylate) (PMMA) under the same condition. The flammability of the PFPMA/MMA copolymer was reduced in comparison with that of the MMA homopolymer. The refractive indices of the PFPMA/MMA copolymers were very close to that of PMMA, and the transmittances of the copolymers were slightly better than that of PMMA. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Preparation and characterization of composites of polyaniline nanorods and multiwalled carbon nanotubes coated with polyaniline
Authors: Su Chang , Wang Gengchao , Huang Farong
Published: September 2007

Composites of polyaniline (PANI) nanorods and multiwalled carbon nanotubes (MWNTs) coated with PANI were prepared by in situ polymerization with perchloric acid as a dopant. Transmission electron microscopy images showed that the coexisting composites of PANI nanorods and MWNTs coated with PANI were formed at low MWNT contents. The interaction between MWNTs and PANI was proved by Fourier transform infrared and ultraviolet–visible spectra. The electrical conductivity of a dedoped PANI/MWNT composite with a 16.3 wt % concentration of MWNTs reached 3.0 × 10−3 S/cm, which was 6 orders of magnitude higher than that of dedoped PANInanorods. The results also showed that coexisting composites of PANI nanorods and MWNTs coated with PANI had high electrochemical activity and good cyclic stability. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Combustion synthesis and luminescence properties of SrAl2O4:Eu2+,Dy3+,Tb3+ phosphor
Authors: Song Huajie , Chen Donghua
Published: September 2007

Eu2+, Dy3+ and Tb3+ co‐doped strontium aluminate phosphor with high brightness and long afterglow was synthesized by a combustion method, using urea as a reducer. The properties of SrAl2O4:Eu2+,Dy3+,Tb3+ phosphor with a series of initiating combustion temperatures, urea concentrations and boric acid molar fractions were investigated. The sample at initiating combustion temperature of 600°C exhibited an intense emission peak at 513 nm, in which the phosphor existed as a single‐phase monoclinic structure. The experimental results showed that the optimum ratio of urea is 2.0 times higher than theoretical quantities and that the suitable molar fraction of H3BO3 is 0.08. The average particle size of the phosphor was 50–80 nm and its luminescence properties were studied systematically. Compared with SrAl2O4:Eu2+,Dy3+ phosphor, the initial luminescence brightness improved from 2.50 candela (cd)/m2 to 3.55 cd/m2 and the long afterglow time was prolonged from 1290 s to 2743 s. Copyright © 2007 John Wiley & Sons, Ltd.
Study on the generation mechanism of reactive oxygen species on calcium peroxide by chemiluminescence and UV‐visible spectra
Authors: Ma Yong , Zhang Bo‐Tao , Zhao Lixia , Guo Guangsheng , Lin Jin‐Ming
Published: September 2007

In the present work, the generation mechanism of reactive oxygen species (ROS) on calcium peroxide (CaO2) was studied. A very intense chemiluminescence (CL) signal was observed when adding an aqueous solution of luminol or 2‐methyl‐6‐(4‐methoxyphenyl)‐3,7‐dihydroimidazo[1,2α]‐pyrazin‐3‐one hydrochloride (MCLA) to a suspension of CaO2. The ROS released on CaO2 were thought to be oxidizing agents leading to CL, and were characterized by CL, UV‐visible (UV‐vis) spectra and the effective scavengers of the special ROS. From experimental results, the hydroxyl (•OH) and superoxide (•O2−) radicals were suggested to exist on the surface of CaO2. A reaction scheme for the formation of the ROS on CaO2 was also proposed and discussed. Of more interest was the finding that the CaO2 which released the •OH and •O2− on the surface exhibited good transition properties compared with alkaline‐earth metal peroxides of the same group (MgO2, BaO2). Copyright © 2007 John Wiley & Sons, Ltd.
Non‐competitive immunoassay for luteinizing hormone in human serum using capillary electrophoresis with chemiluminescence detection
Authors: Zhang Yingxue , Zhang Zhujun , Yang Feng
Published: September 2007

A non‐competitive immunoassay based on capillary electrophoresis (CE) with chemiluminescence (CL) detection has been developed for the determination of luteinizing hormone (LH) in human serum. The work involved the development of separation and CL conditions, allowing for routine analysis of serum samples. In this study, horseradish peroxidase (HRP)‐labelled monoclonal anti‐LH can catalyse the luminol–hydrogen peroxide reaction. The determined LH can react with excessive amount of HRP‐labelled anti‐LH. Within 14 min, free enzyme conjugate and immune complex could be separated in alkaline borate buffer by means of a high voltage (15 kV). To improve sensitivity, a series of measures were adopted, including the choice of para‐iodophenol as a CL enhancer, unique design in detect window. Under the optimal conditions, the calibration curve for LH was established in the concentration range 1–200 mIU/mL and the detection limit was 0.08 mIU/mL. Compared with ELISA, this method decreased the detection limit by about 12 times, and it has been successfully employed in the determination of LH in human serum. Copyright © 2007 John Wiley & Sons, Ltd.
High photoluminescence quantum yield of TiO2 nanocrystals prepared using an alcohothermal method
Authors: Li Yanting , Song Cuihong , Wang Yunqing , Wei Yu , Wei Yongju , Hu Yuzhu
Published: September 2007

Highly dispersible TiO2 nanocrystals (∼6 nm) were prepared by an alcohothermal method. A strong and stable photoluminescence emission with a maximum at 450 nm was observed in the original TiO2 nanocrystals colloid. Compared with the emission from quinine sulphate in 0.05 mol/L sulphuric acid, the emission quantum yield of TiO2 nanocrystals was determined to be about 0.20, which was much higher than the values (0.002 and 0.001) reported in previous studies. The fluorescence micrograph of TiO2 nanocrystals encapsulated in lipsomes shows that TiO2 nanocrystals prepared in such a way have potential application as a fluorescence probe in biological imaging. Research on the luminescence mechanism indicates that the surface state and extent of crystallization of the TiO2 nanocrystals are crucial factors in the high photoluminescence quantum yield obtained in this study. Copyright © 2007 John Wiley & Sons, Ltd.
Precomputing data‐driven tree animation
Authors: Zhang Long , Zhang Yubo , Jiang Zhongding , Li Luying , Chen Wei , Peng Qunsheng
Published: September 2007

We present a data‐driven approach that synthesizes tree animations from a set of pre‐computed motion data. Our approach improves previous motion synthesis algorithms for character animation in several aspects. We first introduce a simple yet effective sampling scheme to generate a rich and reusable motion database for each tree model. We also propose a novel technique to generate a fine set of transitions that are uniformly distributed in the motion database. The transition lengths are adaptively determined according to the similarity of the transiting frame pairs. In the runtime, we employ a greedy searching algorithm to synthesize smooth tree animations under an adjustable wind condition. Experimental results show that our approach achieves comparable quality to physically based methods, while in orders of magnitude faster performance. Copyright © 2007 John Wiley & Sons, Ltd.
Selecting wavelet transform scales for multivariate classification
Authors: Woody Nathaniel A. , Brown Steven D.
Published: September 2007

The wavelet transform is a relatively new method that partitions a signal into components which differ in the frequency of their features. Chemical data can be thought of as a signal being composed of several different frequency components, some more analytically significant than others. Therefore, a wavelet transform can be used to transform chemical data into components, called scales, which differ in the underlying frequency of the signal. These scales possess different signal to noise ratios, or alternatively contain different amounts of information, than the original data. In this manuscript, two classification problems are used to demonstrate how this property can be exploited to improve classification performance. We demonstrate that the classification performance of the individual scales varies, and we show that selectively combining scales results in a classifier with better performance than that of either a classifier trained on the original data or developed on any individual scale. This analysis demonstrates the applicability of the wavelet transform as a simple preprocessing step that can improve classification performance. Copyright © 2007 John Wiley & Sons, Ltd.
c‐Maf interacts with c‐Myb to down‐regulate Bcl‐2 expression and increase apoptosis in peripheral CD4 cells
Authors: Peng Siying , Lalani Saif , Leavenworth Jianmei W. , Ho I‐Cheng , Pauza Mary E.
Published: September 2007

The transcription factor c‐Maf is critical for IL‐4 production and the development of Th2 cells, which promote humoral immunity and protect against extracellular parasites. Yet, little else is known of c‐Maf function in CD4 cells. Here, we identify a novel role for c‐Maf in regulating susceptibility to apoptosis. Overexpression of c‐Maf results in increased susceptibility of CD4 cells to apoptosis induced by multiple stimuli, including growth factor withdrawal, dexamethasone, irradiation, and TCR engagement. This effect is independent of Fas or p53; however, Bcl‐2 expression is reduced in c‐Maf Tg CD4 cells. Immunoprecipitation and Western blot analyses demonstrate that c‐Maf–c‐Myb complex formation is enhanced among T cells from c‐Maf Tg mice compared to non‐Tg littermates following TCR engagement. Unlike non‐Tg T cells, c‐Myb binding to the Bcl‐2 promoter is not detectable in c‐Maf Tg T cells by chromatin immunoprecipitation. In reporter assays, Bcl‐2 promoter activity is reduced by c‐Maf in a dose‐dependent manner. Furthermore, transgene‐mediated Bcl‐2 expression corrects the apoptosis defect observed among c‐Maf Tg CD4 cells. These data suggest that c‐Maf can interact with c‐Myb to reduce Bcl‐2 expression, thereby limiting CD4 cell survival following TCR engagement.
A preliminary study of spiritual self‐schema (3‐S+) therapy for reducing impulsivity in HIV‐positive drug users
Authors: Margolin Arthur , Schuman‐Olivier Zev , Beitel Mark , Arnold Ruth M. , Fulwiler Carl E. , Avants S. Kelly
Published: September 2007

The purpose of this study was twofold. First, pretreatment correlations are presented among impulsivity, intoxicant use, HIV risk behavior, spirituality, and motivation in a sample of 38 HIV‐positive drug users. Second, treatment outcomes are presented from a preliminary study of spiritual self‐schema (3‐S+) therapy—a manual‐guided psychotherapy integrating cognitive and Buddhist psychologies—for increasing motivation for abstinence, HIV prevention, and medication adherence. Impulsivity was negatively correlated with spiritual practices and motivation for recovery, and was positively related to intoxicant use and HIV risk behavior. Relative to a standard care comparison condition, patients completing 3‐S+therapy reported greater decreases in impulsivity and intoxicant use, and greater increases in spiritual practices and motivation for abstinence, HIV prevention, and medication adherence. © 2007 Wiley Periodicals, Inc. J Clin Psychol 63: 979–999, 2007.
Synergism of microwave irradiation and enzyme catalysis in synthesis of isoniazid
Authors: Yadav Ganapati D , Sajgure Ashwini D
Published: September 2007

Isoniazid is a useful antitubercular drug widely employed in combination therapy with rifampicin. The synthesis of isoniazid from ethyl isonicotinate and hydrazine hydrate was studied in non‐aqueous media via lipase‐catalyzed hydrazinolysis under both conventional heating and microwave irradiation by using different supported lipases. Among three different commercial lipases used, namely Novozym 435 (Candida antarctica lipase), Lipozyme RM IM (Rhizomucor miehei lipase) and Lipozyme TL IM (Thermomyces lanuginosus lipase), Novozym 435 was found to be the most effective, with conversion of 54% for equimolar concentrations at 50 °C in 4 h. The rate of reaction as well as final conversion increased synergistically under microwave irradiation in comparison with conventional heating, which showed 36.4% conversion, even after 24 h, for the control experiment. Effects of various process parameters such as speed of agitation, catalyst loading, substrate concentration, product concentration and temperature were studied. A kinetic model is also described. Copyright © 2007 Society of Chemical Industry
Biological nutrient removal in a sequencing batch reactor using ethanol as carbon source
Authors: Puig Sebastià , Coma Marta , van Loosdrecht Mark CM , Colprim Jesús , Balaguer Maria D
Published: September 2007

BACKGROUND: When organic matter is limiting for biological nutrient removal (BNR) from wastewater, external organic carbon can be added to a wastewater treatment plant (WWTP). This increases the overall treatment cost, so the choice of substrate is critical. The effect of using ethanol as the carbon source for BNR is investigated.

RESULTS: The results clearly showed that using ethanol as a carbon source is a promising strategy for removing nutrients from wastewater. Effluent concentrations of 3.0 mg total nitrogen (TN) L−1 (96% N removal efficiency) and 0.05 mg phosphate (P‐PO4) L−1 (99.9% P removal efficiency) were obtained. Furthermore, tests performed in order to identify the carbon source used by polyphosphate‐accumulating organisms (PAOs) showed that the phosphorus release/carbon uptake ratio using ethanol (0.41 mmol P mmol−1 C) was slightly lower than that with acetate (0.50 mmol P mmol−1 C) but close to that with propionate (0.42 mmol P mmol−1 C).

CONCLUSION: Therefore, taking into account the results presented for ethanol‐acclimatised biomass and the fact that the cost of ethanol is lower than that of acetate or propionate, ethanol can be considered as an alternative carbon source if one is needed in a WWTP. Copyright © 2007 Society of Chemical Industry
Nitrification monitoring in a biofilter treating pig manure
Authors: Gilbert Yan , Lessard Paul , Le Bihan Yann , Aubry Geneviève , Duchaine Caroline , Veillette Marc
Published: September 2007

BACKGROUND: Nitrogen removal by organic biofilters treating pig manure is incomplete and has to be optimized. This could be achieved by promoting the activity of denitrifiers, this being the limiting factor for nitrogen removal in this kind of process. However, changing the operating conditions could impair nitrification; no data are currently available about the activity and distribution of nitrifiers in organic biofilters. A better knowledge of the process of colonization by nitrifiers is needed to determine their potential to oxidize ammonia and whether they share the same physical space as denitrifiers or not.

RESULTS: Data showed that nitrifiers were principally localized near the surface and that a microbiological gradient, in terms of nitrifying activity, was present from top to bottom. Moreover, in each section studied, the potential nitrifying activity measured was always higher than the observed nitrifying activity. These results suggest that the biomass had the capacity to oxidize more ammonia and that these transformations occurred near the surface of the biofilter. However, nitrifying activities were not limited by environmental factors but rather by the concentration of ammonia supplied to the process.

CONCLUSIONS: Because denitrifiers and nitrifiers share the same physical space in this kind of process, particular precautions will have to be taken to maintain nitrification, while modifying conditions to promote denitrifier activity. Copyright © 2007 Society of Chemical Industry
Effect of process variables on liquid hot water pretreatment of wheat straw for bioconversion to fuel‐ethanol in a batch reactor
Authors: Pérez José A , González Alberto , Oliva J Miguel , Ballesteros Ignacio , Manzanares Paloma
Published: September 2007

BACKGROUND: Crop residues as wheat straw are potential sources for fuel‐ethanol production as an alternative to current production based on starch‐ or sugar‐containing feedstocks. In this work, the effect of liquid hot water (LHW) process parameters, i.e. temperature (170 and 200 °C), residence time (0 and 40 min), solid concentration (5% and 10% (w/v)) and overpressure applied in the reactor (30 bar and no overpressure), on pretreatment of wheat straw was studied using a full factorial experimental design. Pretreatment effectiveness was evaluated based on the composition of the solid and liquid fractions obtained after filtration of pretreated material, and the susceptibility of the solid fraction to enzymatic hydrolysis (EH) using commercial cellulases.

RESULTS: Statistical analysis showed that only temperature and time, within the limits of the experimental range, have a significant effect on the responses studied. While the effect of pretreatment time in hemicellulose‐derived sugar recovery in prehydrolyzate depends on temperature, EH yield was enhanced as both temperature and time were increased. Maximum EH yield was 96 g glucose per 100 g potential glucose in pretreated residue. Xylan and acetyl groups content remaining in solid residue after pretretament, which were found to be directly correlated, had a marked effect on pretreated substrate degradability.

CONCLUSIONS: LHW is an effective pretreatment to enhance the potential of wheat straw as substrate for ethanol production. Maximum hemicellulose‐derived sugar recovery (53% of content in raw material) and EH yield (96% of theoretical) fall within different temperature and time intervals, suggesting separate optimization designs for these responses. Copyright © 2007 Society of Chemical Industry
Upgrading biomass wastes in chemical technology. Humic acid‐like matter isolated from compost as chemical auxiliary for textile dyeing
Authors: Savarino Piero , Montoneri Enzo , Biasizzo Miriam , Quagliotto Pierluigi , Viscardi Guido , Boffa Vittorio
Published: September 2007

BACKGROUND: In the context of the modern concern regarding rapid consumption and low availability of fossil sources of energy and chemicals, urban and agro‐industrial sources of chemicals represent interesting environmentally friendly alternatives. A recent paper has shown that a humic acid‐like material extracted from urban and green wastes compost exhibits very good surfactant properties. A large number of technological applications could possibly use this material as a chemical auxiliary. This paper reports on the performance of the material as a chemical auxiliary in textile dyeing.

RESULTS: The compost‐isolated humic acid‐like bio‐surfactant is shown to perform in nylon 6 microfiber dyeing by water soluble and insoluble dyes as well as and more conveniently than commercial sodium dodecylsulfate (SDS) and sodium dodecylbenzenesulfonate (SDBS). With both types of dye the bio‐surfactant allows the same quality of dyed product as the synthetic surfactants do, but at lower additive concentration. From process cost and environmental impact points of view, the bio‐surfactant has the advantages of operating at much lower additive concentrations and should be available at significantly lower cost than the synthetic surfactants.

CONCLUSION: The results suggest that biomass wastes may be a low cost renewable source of chemicals with friendly environmental impact. Such a perspective implies economic and environmental benefits deriving from a new waste management technology that considers biomass waste as a source of chemicals, and from lower oil consumption in the manufacture of synthetic surfactants. Copyright © 2007 Society of Chemical Industry
Extraction kinetics of cerium(IV) from sulfuric acid medium by the primary amine N1923 using a constant interfacial area cell with laminar flow
Authors: Liu Jianjun , Wang Yanliang , Li Deqian
Published: September 2007

BACKGROUND: Thermodynamic studies on Ce(IV) extraction with primary amine N1923 demonstrate that primary amine N1923 is an excellent extractant for separation of Ce(IV) from Re(III). In order to clarify the mechanism of extraction and to optimize the parameters in practical extraction systems used in the rare earth industry, the extraction kinetics was investigated using a constant interfacial area cell with laminar flow in the present work.

RESULTS: The data indicate that the rate constant (kao) becomes constant when stirring speed exceeds 250 rpm. The apparent forward extraction rate is calculated to be 10−1.70. The activation energy (Ea) was calculated to be 20.5 kJ/mol from the slope of log kao against 1000/T. The minimum bulk concentration of the extractant necessary to saturate the interface (Cmin) is lower than 10−5 mol L−1.

CONCLUSION: Studies of interfacial tension and the effects of stirring rate and specific interfacial area on the extraction rate show that the extraction rate is kinetically controlled, and a mass transfer model has been proposed. The rate equation has been obtained as: − d[Ce(IV)]/dt = 10−1.70[Ce(IV)] [(RNH3)2SO4]1.376. The rate‐controlling step has been evaluated from analysis of the experimental results. Copyright © 2007 Society of Chemical Industry
The FE65 proteins and Alzheimer's disease
Authors: McLoughlin Declan M. , Miller Christopher C.J.
Published: September 2007

The FE65s (FE65, FE65L1, and FE65L2) are a family of multidomain adaptor proteins that form multiprotein complexes with a range of functions. FE65 is brain‐enriched, whereas FE65L1 and FE65L2 are more widely expressed. All three members contain a WW domain and two PTB domains. Through the PTB2 domain, they all interact with the Alzheimer's disease amyloid precursor protein (APP) intracellular domain (AICD) and can alter APP processing. After sequential proteolytic processing of membrane‐bound APP and release of AICD to the cytoplasm, FE65 can translocate to the nucleus to participate in gene transcription events. This role is further mediated by interactions of FE65 PTB1 with the transcription factors CP2/LSF/LBP1 and Tip60 and the WW domain with the nucleosome assembly factor SET. However, FE65 target genes have not yet been confirmed. The FE65 PTB1 domain also interacts with two cell surface lipoproteins receptors, the low‐density lipoprotein receptor‐related protein (LRP) and ApoEr2, forming trimeric complexes with APP. The FE55 WW domain also binds to mena, through which it functions in regulation of the actin cytoskeleton, cell motility, and neuronal growth cone formation. While single knockout mice appear normal, double FE65−/−/FE65L1−/− mice have substantial neurodevelopmental defects. These include heterotopic neurons and axonal pathfinding defects, findings similar to findings in both Mena and triple APP:APLP1:APLP2 knockout mice and also lissencephalopathies in humans. Thus APPs, FE65s, and mena may act together in a developmental signalling pathway. This article reviews the known functions of the FE65 family and their role in APP function and Alzheimer's disease. © 2007 Wiley‐Liss, Inc.
Pressure effects on inter‐ and intramolecular vibrations in hydrogen‐bonded L‐ascorbic acid crystal
Authors: Shimada Hiroko , Nibu Yoshinori , Shimada Ryoichi
Published: September 2007

Pressure effects on the Raman spectra due to the inter‐ and intramolecular vibrations of the L‐ascorbic acid crystal were studied. The intensity of the Raman bands due to the intermolecular vibrations varies in three different ways by application of pressure. The bands of the first group become stronger, those of the second one become weaker and the third group shows no prominent change in their intensity with increasing pressure. The bands due to the intermolecular vibrations show a blue shift, while the bands due to the intramolecular vibrations shift to the blue or red depending on the vibrational modes by application of pressure. The bands assigned to the OH stretching vibrations shift to the red, the bands assigned to the CO and CC stretching vibrations shift a little to the red and the bands assigned to the other vibrations shift to the blue under high pressure. The following conclusions were derived. (1) The hydrogen bonds forming helixes become stronger and the isolated hydrogen bond becomes weaker with increasing pressure. (2) The bands of the first group owing to the intermolecular vibrations are ascribed to the vibrations related to the helix hydrogen bonds and the second group bands to the isolated hydrogen bond. (3) The CO stretching vibration couples with the CC stretching vibration. (4) The phase transitions take place at 1.8 and 4 GPa in the crystal. Copyright © 2007 John Wiley & Sons, Ltd.
Al‐for‐Fe substitution in hematite: the effect of low Al concentrations in the Raman spectrum of Fe2O3
Authors: Zoppi A. , Lofrumento C. , Castellucci E. M. , Sciau Ph.
Published: September 2007

Five different mixed Al‐hematites with an aluminium molar content varying from 0 to 10% were investigated by micro‐Raman spectroscopy to study the effect of Al‐for‐Fe substitution on the hematite lattice. A red shift of hematite vibrational wavenumbers and a line broadening were observed; also a shoulder located near 430 cm−1 and a broad band at 670 cm−1 developed. The variation of the spectral features is discussed in terms of a local disorder correlated to the insertion of Al3+ ions into the Fe(O)6 octahedra constituting hematite structure. A multivariate analysis was also carried out on the spectral data to distinguish between the doped samples analysed. Copyright © 2007 John Wiley & Sons, Ltd.
Miscibility and Biodegradability of Silk Fibroin/Carboxymethyl Chitin Blend Films
Authors: Wongpanit Panya , Tabata Yasuhiko , Rujiravanit Ratana
Published: September 2007

Blend films of silk fibroin and carboxymethyl chitin were prepared by solution casting using water as a cosolvent. The blend films were subjected to post‐treatment with an aqueous methanol solution to induce β‐sheet formation of silk fibroin. The miscibility of the blend films both before and after methanol treatments was investigated in terms of chemical interactions, morphologies, thermal properties, and crystal structures by using FTIR spectroscopy, SEM, DSC, and XRD. The results indicate that the blend between silk fibroin and CM‐chitin was semi‐miscible because only the amorphous parts of the polymers were compatible with each other. The enzymatic degradation showed that the incorporation of CM‐chitin enhanced biodegradability and swelling ability of silk fibroin.

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Crystallization and Morphological Features of Syndiotactic/Atactic Polystyrene Blends at High Temperatures
Authors: Wang Chi , Fan Young‐Da , Chen Chung‐Chiu , Hung Chung‐Hau
Published: September 2007

Crystalline/amorphous binary mixtures of polystyrene with different tacticities, syndiotactic/atactic isomers (sPS/aPS), have been systematically studied to reveal the composition dependence of the blend morphologies, i.e., sPS lamellar structure and aPS diluent segregation, developed after isothermal crystallization. To reveal the molecular weight effect of the aPS diluents, four different $\overline M _{\rm w}$ of aPS were used to prepare blends with various compositions. After being melt crystallized isothermally at 250 °C, all blends were investigated by means of POM, WAXS, and SAXS as well as SEM and TEM to reveal the spherulitic and lamellar morphologies developed.

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On‐Line HPLC‐NMR of PS‐b‐PMMA and Blends of PS and PMMA: LCCC‐NMR at Critical Conditions of PS
Authors: Hiller Wolf , Sinha Pritish , Pasch Harald
Published: September 2007

Blends and copolymers of PS and PMMA were analysed by LC coupled to 1H NMR at the critical point of adsorption. The separation of the polymers was achieved at chromatographic conditions that correspond to the critical point of PS and the size‐exclusion mode of PMMA. Copolymers and blends were analysed by on‐line coupled 1H NMR. For the homopolymer blends, separation into the components was achieved, while the copolymers were separated with regard to the block lengths of the PMMA blocks. The tacticity of the PMMA blocks could be determined as a function of molar mass by HPLC‐NMR. This technique can deliver the true molar mass and the true chemical composition of the copolymers.

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Molecular Dynamics of Podand Studied by Broadband Dielectric and Nuclear Magnetic Resonance Spectroscopies
Authors: Orozbaev Bakyt , Fojud Zbigniew , Makrocka‐Rydzyk Monika , Schroeder Grzegorz , Jurga Stefan
Published: September 2007

Nuclear magnetic resonance (NMR) and broadband dielectric spectroscopies (BDS) were used to analyze the molecular dynamics in P10.3H Podand. The temperature studies of NMR line and magnetic spin–lattice relaxation times accompanied by DS investigation enabled us to distinguish three main dynamical processes connected with the motions of the P10.3H Podand chains. In the low‐temperature region the magnetic relaxation was associated with fast axial C3 rotation of methyl groups. Moreover, two other independent processes were observed and interpreted as (i) segmental motion of both oxyethylene and ethylene units, and (ii) the overall motion involved in the melting process.

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Processing and Properties of Biobased Blends from Soy Meal and Natural Rubber
Authors: Wu Qiangxian , Selke Susan , Mohanty Amar K.
Published: September 2007

Vulcanized blends from soy meal and natural rubber were successfully processed through semi‐pilot scale extrusion, roll milling and compression‐molding. Blends containing about 50 wt.‐% of soy meal are elastic and water resistant, compared with the brittle and hydrophilic soy meal. The natural rubber component was well embedded into the soy meal matrix, indicating the existence of an interaction between them. The glass transition temperature of the rubber component in the blends increased due to the existence of this interaction. Calcium sulfate, as a compatibilizer, was a physical cross‐linker to the proteins in the soy meal and in the rubber. The morphological analysis of the soy meal and natural rubber blend through scanning electron microscopy revealed a partial compatibility of the blend. The blends containing near 50 wt.‐% of inexpensive soy meal have potential for various applications.

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Amine Modifiers with an s‐Triazine Ring for Unsaturated Polyester Resins, 2
Authors: Duliban Jerzy
Published: September 2007

The paper deals with the synthesis of amine modifiers for unsaturated polyester resins obtained from N‐phenyl‐2‐amineethanol and 2,4‐dichloro‐6‐methoxy‐1,3,5‐triazine (modifier A), 2‐chloro‐4,6‐dimethoxy‐1,3,5‐triazine (modifier B) or with cyanuric chloride (modifier C). Properties of amine modifiers for unsaturated polyester resins are presented. The modifiers were incorporated into resins at the polycondensation stage.

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Inverse problem for the Sturm–Liouville equation on a star‐shaped graph
Authors: Pivovarchik V.
Published: September 2007

The problem of small vibrations of a graph consisting ofnsmooth inhomogeneous stretched strings joined at the vertex with the pendant ends fixed is reduced to the Sturm–Liouville boundary problem on a star‐shaped graph. The obtained problem occurs also in quantum mechanics. The spectrum of such a problem which consists of normal eigenvalues accumulating at infinity is investigated in comparison with the union of spectra of the Dirichlet–Dirichlet problems on the edges of the graph. It is shown that the eigenvalues of the spectra interlace in certain sense, thus an analogue of Sturm theorem is established. If the (n+ 1) spectra (the spectrum of the boundary problem on the graph and thenspectra of the mentioned Dirichlet–Dirichlet problems) do not intersect the inverse problem of recovering the potentials on the edges from the (n+ 1) spectra is uniquely solvable. The procedure of recovering of the potentials is presented. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A Simple Imprint Method for Multi‐Tiered Polymer Nanopatterning on Large Flexible Substrates Employing a Flexible Mold and Hemispherical PDMS Elastomer
Authors: Lee Nae Yoon , Kim Youn Sang
Published: September 2007

This work reports a facile method to fabricate multi‐tiered polymer nanopatterns on SU‐8 by the combination of imprint‐ and photo‐lithography. First, SU‐8 is imprint patterned using a polymeric flexible mold with an anti‐adhesion coating that is deposited on a transparent and flexible substrate, at room temperature under low pressure. Next, the resulting SU‐8 nanopatterns are exposed to UV light through a chromium mask by a photolithographic process. Removal of the unexposed SU‐8 leaves behind multi‐tiered structures. The use of a hemispherical poly(dimethylsiloxane) pad facilitates the evacuation of trapped air during the imprinting process. Line/space patterns of 500 nm with the smallest line width of 200 nm were homogeneously imprint‐patterned on SU‐8 on a large flexible substrate, and three‐tiered structures, ranging in thickness from 300 nm to 2 µm, were successfully formed.

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Palladium Aryl Sulfonate Phosphine Catalysts for the Copolymerization of Acrylates with Ethene
Authors: Skupov Kirill M. , Marella Pooja R. , Simard Michel , Yap Glenn P. A. , Allen Nathan , Conner David , Goodall Brian L. , Claverie Jerome P.
Published: September 2007

The reaction of 2‐[bis(2‐methoxy‐phenyl)phosphanyl]‐4‐methyl‐benzenesulfonic acid (a) and 2‐[bis(2′,6′‐dimethoxybiphenyl‐2‐yl)phosphanyl]benzenesulfonic acid (b) with dimethyl(N,N,N′,N′‐tetramethylethylenediamine)‐palladium(II) (PdMe2(TMEDA)) leads to the formation of TMEDA bridged palladium based polymerization catalysts (1a and 1b). Upon reaction with pyridine, two mononuclear catalysts are formed (2a and 2b). These catalysts are able to homopolymerize ethylene and also copolymerize ethylene with acrylates or with norbornenes. With ligand b, high molecular weight polymers are formed in high yields, but higher comonomer incorporations are obtained with ligand a.

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Simple Silole‐Containing Polyfluorene for White Electroluminescence with Simultaneous Blue, Green, and Red Emission
Authors: Wang Feng , Wang Lei , Chen Junwu , Cao Yong
Published: September 2007

Novel conjugated silole‐containing polyfluorenes, with green‐ and red‐emissive siloles on the backbone of the blue‐emissive polyfluorene are synthesized for white light electroluminescence (EL) from a single polymer with simultaneous red, green, and blue (RGB) emission. The CIE coordinates (0.33, 0.36) of the white light EL spectra are very close to that for pure white light (0.33, 0.33). The EL spectra are also quite stable at different applied voltages or brightness. The relative intensities for the three RGB peaks, at 450, 505, and 574 nm, were 0.94, 1, and 0.97, respectively, which demonstrates a balanced simultaneous RGB emission. A maximum luminous efficiency of 2.03 cd · A−1 for a brightness of 344 cd · m−2, and a luminous efficiency of 1.86 cd · A−1 for a more practical brightness of 2 703 cd · m−2, were achieved.

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Continuous Online Rapid Size Exclusion Chromatography Monitoring of Polymerizations ‐ CORSEMP
Authors: Rosenfeld Carine , Serra Christophe , O'Donohue Stephen , Hadziioannou Georges
Published: September 2007

We report the development of a new method for online characterization of polymers, termed Continuous Online Rapid Size‐Exclusion chromatography Monitoring of Polymerizations (CORSEMP). It consists of automatic samplings, dilutions and injections every 12 min of polymers synthesized in continuous flow. The system allows molecular weight and molecular weight distribution of polymers to be monitored ‘near real‐time’ by means of a chromatographic column. This technique is well adapted to assessment of the effects of stepwise modifications of operating conditions over the dynamics of the reactor by running high‐throughput experiments and shows itself to be a convenient tool for polymer library synthesis.

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The effects of anticholinergic drugs on attention span and short‐term memory skills in children
Authors: Giramonti Karla M. , Kogan Barry A. , Halpern Leslie F.
Published: September 2007

Aims

Studies have shown cognitive problems in adults treated with anticholinergics. It is unclear if children are also susceptible to anticholinergic adverse effects. This study evaluates the effects of long‐acting oxybutynin and tolterodine on short‐term memory and attention in children with urgency and urge incontinence.

Methods

Children with urgency or urge incontinence were recruited to take part in a prospective, randomized double‐blinded placebo controlled trial using long‐acting oxybutynin or tolterodine. Patients underwent a baseline test of their memory/recall ability and attention span using a standardized developmental/neuropsychological assessment tool. They were then randomized to either medication or placebo with retesting in 2 weeks, at which time they were crossed. They were retested after the second 2 weeks.

Results

Fourteen childrens (9 boys and 5 girls), ranging in age from 5 to 11 (M = 7.7) participated in the study. Attention and Memory scores increased over time in all children, however, the analyses showed no significant negative effects of anticholinergic medications on Attention or Memory. Indeed, though not statistically significant, trends were for improvement in test scores in both areas.

Conclusions

Our results in a double blinded cross‐over trial suggest that long‐acting oxybutynin and tolterodine do not have a deleterious effect on children's attention and memory. Other cognitive functions may be affected. Neurourol. Urodynam. 27:315–318, 2008. © 2007 Wiley‐Liss, Inc.
The implications of differences between employer and worker employment/earnings reports for policy evaluation
Authors: Wallace Geoffrey L. , Haveman Robert
Published: September 2007

Differences in administrative (UI) and survey (S) records on employment and earnings have substantial implications for assessing the impact of a variety of public interventions, such as welfare‐to‐work and employment training programs, and especially the state‐oriented welfare reform legislation of 1996. We use data from the 1998 and 1999 waves of the Child Support Demonstration Evaluation (CSDE) Resident Parent Surveys to explore individual differences between survey and UI employment and earnings reports for a Wisconsin sample of current and former welfare recipients. After exploring the potential causes of misreports from both sources, we document the degree of discrepancy between survey and UI earnings and employment measures and assess the difference between the two earnings measures in estimates of simple human capital (earnings) functions. Last, we evaluate the correspondence of the two measures with “hardship” indicators of economic well‐being.
Glomerular barrier dysfunction in glomerulosclerosis‐ resistant Milan rats with experimental diabetes: the role of renal haemodynamics
Authors: Pugliese G , Ricci C , Iacobini C , Menini S , Fioretto P , Ferrandi M , Giardino LA , Armelloni S , Mattinzoli D , Rastaldi MP , Pugliese F
Published: September 2007

Rats of the Milan hypertensive strain (MHS) are resistant to both hypertensive and diabetic renal disease. Genetically determined hypertrophy of intrarenal arteries has been suggested as the putative mechanism preventing transmission of systemic hypertension to the glomerular microcirculation or diabetes‐induced loss of autoregulation, which lead to glomerular hypertension and consequent podocyte injury and proteinuria. This study aimed to investigate glomerular barrier function and structure in ageing and diabetic MHS rats under basal conditions and after injection of 2.5 g of bovine serum albumin (BSA) causing increased workload and possibly removing haemodynamic protection by inducing renal cortical vasodilatation. Genetically related rats of the Milan normotensive strain (MNS) served as a proteinuric counterpart. No change in renal function or structure was detected in diabetic MHS rats, whereas MNS rats developed diabetic nephropathy superimposed on that occurring spontaneously in this strain. Diabetic, but not non‐diabetic, MHS rats showed significantly reduced synaptopodin and nephrin expression, though to a lesser extent than non‐diabetic and diabetic MNS rats, together with unchanged podocyte number, density and structure and no proteinuria. Agrin expression was significantly altered in diabetic versus non‐diabetic MHS animals, whereas collagen I was expressed only in diabetic MHS rats and collagen IV content did not change significantly between the two groups. Upon BSA injection, proteinuria increased markedly and abundant BSA was detected only in kidneys from diabetic MHS rats. BSA injection was associated with changes in intrarenal arteries suggesting vasodilatation, without any influx of inflammatory cells. These data indicate that while MNS rats show marked changes in the glomerular filtration barrier with either age or diabetes, glomerulosclerosis‐resistant MHS rats develop only minor diabetes‐induced podocyte (and extracellular matrix) alterations, which are not associated with proteinuria unless they are unmasked by an increased workload or removal of the haemodynamic protection. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Adrenal axis function after high‐dose steroid therapy for childhood acute lymphoblastic leukemia
Authors: Einaudi Silvia , Bertorello Nicoletta , Masera Nicoletta , Farinasso Loredana , Barisone Elena , Rizzari Carmelo , Corrias Andrea , Villa Alessia , Riva Francesca , Saracco Paola , Pastore Guido
Published: September 2007

Background A 4‐week course of high‐dose glucocorticoids may cause prolonged adrenal suppression even after a 9‐day tapering phase. In this study, adrenal function and signs and symptoms of adrenal insufficiency were prospectively assessed in children with acute lymphoblastic leukemia (ALL) after induction treatment including high‐dose prednisone (PDN) or dexamethasone (DXM). Procedures Sixty‐four children with ALL, treated according to the AIEOP ALL 2000 Study protocol, underwent low dose ACTH (LD‐ACTH) stimulation 24 hr after the last tapered steroid dose. In those with impaired cortisol response, additional LD ACTH tests were performed every 1–2 weeks until cortisol levels normalized. Signs and symptoms of adrenal insufficiency were recorded during the observation period. Results All patients had normal basal cortisol values at diagnosis. Twenty‐four hours after last glucocorticoid dose, morning cortisol was reduced in 40/64 (62.5%) patients. LD‐ACTH testing showed adrenal suppression in 52/64 (81.5%) patients. At the following ACTH test 7–14 days later, morning cortisol values were reduced in 8/52 (15.4%) patients and response to the test was impaired in 12/52 (23%). Adrenal function completely recovered in all patients within 10 weeks. No difference was found between patients treated with PDN or DXM. Almost 35% of children with impaired cortisol values at the first test developed signs or symptoms of adrenal insufficiency. One child developed a severe adrenal crisis during adrenal suppression. Conclusions High‐dose glucocorticoid therapy in ALL children may cause prolonged adrenal suppression and related clinical symptoms. Laboratory monitoring of cortisol levels and steroid coverage during stress episodes may be indicated. Pediatr Blood Cancer 2008;50:537–541. © 2007 Wiley‐Liss, Inc.