bluuebunny/crossref_metadata_2025 huggingface dataset:
Stable Ion and Electrophilic Substitution (Nitration and Bromination) Study of A‐Ring Substituted Phenanthrenes: Novel Carbocations and Substituted Derivatives; NMR, X‐ray Analysis, and Comparative DNA Binding
Authors: Brulé Cédric , Laali Kenneth K. , Okazaki Takao , Musafia Tamara , Baird William M.
Published: November 2006

Persistent carbocations were generated from five A‐ring mono‐ and di‐substituted phenanthrenes [3‐OMe; 4‐OMe, 1,3‐bis(OMe), 2,4‐bis(OMe), and 1,3‐bis(Me)]. In all cases protonation occurs in the A‐ring, ortho/para relative to methoxy or methyl substituent(s). Complete NMR assignments of the resulting carbocations are reported and their charge delocalization modes are discussed. Mild nitration (with 20–50 % aqueous HNO3 at –10 °C or at room temp.) and bromination (NBS/MeCN/room temp.) of these substrates resulted in the synthesis of several novel mononitro‐/dinitro‐ as well as monobromo/dibromo derivatives, including those with nitro or bromo substituent in the bay‐region. Correspondence between the site of attack in low‐temperature protonation study and nitro substitution in ambient mild nitrations are examined. Complete NMR assignments for the new derivatives are reported as well as X‐ray structures for 2,4‐dimethoxy‐1‐nitro‐ and 1,3‐dimethyl‐4‐nitrophenanthrenes. A comparative DNA binding study with MCF cells on three of the synthesized mononitro and one dinitro derivative showed that 1,3‐dimethyl‐9‐nitro‐ (nitro at the meso position), 3‐methoxy‐4‐nitro‐ (nitro in bay‐region), and 1,3‐dimethoxy‐4,9‐dinitrophenanthrenes (nitro in both meso and bay‐regions) formed DNA adducts. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
The effect of linguistic abstraction on interpersonal distance
Authors: Reitsma‐van Rooijen Margreet , Semin Gün R. , van Leeuwen Esther
Published: November 2006

It is well known that people describe positive behaviors of others close to them (e.g., in‐group member, friend) in abstract terms, but with concrete terms in the case of people who they are not close to (e.g., out‐group member, enemy). In contrast, negative behaviors of people who we are close to are described in concrete terms, but in abstract terms for people who are distant. However, the communicative impact of such subtle differences in language use on a receiver who is also the actor of the behavior being described has never been addressed. We hypothesized and found that a positive abstract message compared to a positive concrete message leads to perceived proximity to the sender, while a negative abstract message compared to a negative concrete message leads to perceived distance. The implications of this study, which is the first to show the communicative impact of biased language use, are discussed. Copyright © 2006 John Wiley & Sons, Ltd.
Form roughness and the absence of secondary flow in a large confluence–diffluence, Rio Paraná, Argentina
Authors: Parsons Daniel R. , Best James L. , Lane Stuart N. , Orfeo Oscar , Hardy Richard J. , Kostaschuk Ray
Published: November 2006

Confluence–diffluence units are key elements within many river networks, having a major impact upon the routing of flow and sediment, and hence upon channel change. Although much progress has been made in understanding river confluences, and increasing attention is being paid to bifurcations and the important role of bifurcation asymmetry, most studies have been conducted in laboratory flumes or within small rivers with width:depth (aspect) ratios less than 50. This paper presents results of a field‐based study that details the bed morphology and 3D flow structure within a very large confluence–diffluence in the Río Paraná, Argentina, with a width:depth ratio of approximately 200. Flow within the confluence–diffluence is dominated largely by the bed roughness, in the form of sand dunes; coherent, channel‐scale, secondary flow cells, that have been identified as important aspects of the flow field within smaller channels, and assumed to be present within large rivers, are generally absent in this reach. This finding has profound implications for flow mixing rates, sediment transport rates and pathways, and thus the interpretation of confluence–diffluence morphology and sedimentology. Copyright © 2006 John Wiley & Sons, Ltd.
Bedrock erosion and relief production in the northern Flinders Ranges, Australia
Authors: Quigley Mark , Sandiford Mike , Fifield Keith , Alimanovic Abaz
Published: November 2006

Cosmogenic 10Be concentrations in exposed bedrock surfaces and alluvial sediment in the northern Flinders Ranges reveal surprisingly high erosion rates for a supposedly ancient and stable landscape. Bedrock erosion rates increase with decreasing elevation in the Yudnamutana Catchment, from summit surfaces (13·96 ± 1·29 and 14·38 ± 1·40 m Myr−1), to hillslopes (17·61 ± 2·21 to 29·24 ± 4·38 m Myr−1), to valley bottoms (53·19 ± 7·26 to 227·95 ± 21·39 m Myr−1), indicating late Quaternary increases to topographic relief. Minimum cliff retreat rates (9·30 ± 3·60 to 24·54 ± 8·53 m Myr−1) indicate that even the most resistant parts of cliff faces have undergone significant late Quaternary erosion. However, erosion rates from visibly weathered and varnished tors protruding from steep bedrock hillslopes (4·17 ± 0·42 to 14·00 ± 1·97 m Myr−1) indicate that bedrock may locally weather at rates equivalent to, or even slower than, summit surfaces. 10Be concentrations in contemporary alluvial sediment indicate catchment‐averaged erosion at a rate dominated by more rapid erosion (22·79 ± 2·78 m Myr−1), consistent with an average rate from individual hillslope point measurements. Late Cenozoic relief production in the Yudnamutana Catchment resulted from (1) tectonic uplift at rates of 30–160 m Myr−1 due to range‐front reverse faulting, which maintained steep river gradients and uplifted summit surfaces, and (2) climate change, which episodically increased both in situ bedrock weathering rates and frequency–magnitude distributions of large magnitude floods, leading to increased incision rates. These results provide quantitative evidence that the Australian landscape is, in places, considerably more dynamic than commonly perceived. Copyright © 2006 John Wiley & Sons, Ltd.
Transplanted Schwann cells, not olfactory ensheathing cells, myelinate optic nerve fibres
Authors: Li Ying , Li Daqing , Raisman Geoffrey
Published: November 2006

In a previous study we found that olfactory ensheathing cells transplanted into complete retrobulbar transections of the rat optic nerve mediated regeneration of severed retinal ganglion cell axons through the graft region. Although the regenerating axons were ensheathed by the transplanted cells, none of the regenerating axons became myelinated by either central or peripheral type myelin. In the present study we used the same operative procedure but transplanted Schwann cells instead of olfactory ensheathing cells. As with the olfactory ensheathing cell transplants the Schwann cells transplants also induced regeneration of the severed retinal ganglion cell axons into the graft region. In contrast to the situation with the olfactory ensheathing cell transplants, however, a considerable number of the regenerating axons became myelinated by peripheral type myelin produced by the transplanted Schwann cells. This observation identifies a further distinction between these two cell types which are phenotypically similar in many ways, but which have been shown to have major functional differences with regard to regeneration in spinal cord lesions. © 2006 Wiley‐Liss, Inc.
A basic study on humidity recovery by using micro‐porous media (Effects of thermal condition of fluids and geometrical condition of apparatus on transport performance)
Authors: Wang Shixue , Utaka Yoshio , Tasaki Yutaka
Published: November 2006

Using an experimental apparatus to examine the performance of heat and mass transfer between constant‐temperature water and dry air through a porous plate having extremely small pores, the effects of the thermal conditions in the fluids and the geometric condition of the apparatus on moisture transport were measured. The effects of water temperature, thickness of the porous plate, and channel height of the flowing air on moisture transport are noticeable. However, the effect of air temperature in the channel inlet on moisture transport is slight. In addition, in order to evaluate the degree of air humidity absorption, a parameter called the moisture absorption rate was introduced. The moisture absorption rate was shown to decrease with increasing air velocity and varies only slightly for a plate thickness of 1 mm and decreases for a plate thickness of 3.5 mm with increasing water temperature. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 35(8): 568–581, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20133
Viscosity measurements of ethylene glycol solution with flow drag reduction additives
Authors: Haruki Naoto , Inaba Hideo , Horibe Akihiko , Tanaka Shinji
Published: November 2006

The viscous characteristics of ethylene glycol (EG) solution with flow drag reduction additive have been investigated experimentally. In this study, oleyldihydoroxyetyl amineoxide (ODEAO) was used as the flow drag reduction additive, and an aqueous solution of EG was used as a secondary refrigerant. The viscosity of the EG solution with ODEAO was measured with a rotational rheometer. The experimental parameters of viscosity measurement were the temperature of the EG solution with ODEAO, the ODEAO concentration, and the EG concentration. From the experimental results, the apparent viscosity of the EG solution with ODEAO showed SIS (shear induced state). The non‐linear dependence of shear stress on shear rate has been well approximated by the power‐law model under high shear conditions. The power‐law contents, pseudoplastic viscosity, and index number have been estimated for each experimental parameter. Using the measured viscosity and non‐dimensional analysis, the flow drag and heat transfer reduction effect of the EG solution with ODEAO has been investigated. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 35(8): 553–567, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20134
Characteristics of the thermal decomposition of biomass and numerical simulation for the gasification of decomposed mixtures
Authors: Takeno Keiji , Ichinose Toshimitsu , Fukuda Norihiro
Published: November 2006

As an initial step in clarifying the mechanisms of the combustion and gasification of biomass, fundamental experiments on the thermal decomposition and numerical simulation for the elementary reaction of decomposed chemical species have been performed. In the experiment, various kinds of biomass particles were rapidly heated by applying an electrically induced magnetic field to the metal tray on which the object particles had been placed. It was clarified that for the two decomposition temperatures of 590 and 1040 °C investigated, the relationship between decomposition rate and heating time was the same, but that the components of the decomposed species were substantially different; the mole fraction of C6–C9 components for the low temperature of 590 °C was 3 to 10 times greater than that corresponding to 1040 °C. Furthermore, a close relationship was ascertained between the percentage of heavy species (C10–C20) and the amount of lignin contained in the biomass. Numerical simulation indicated that these heavy species could decompose to C1 and H2 at over 1000 °C with H2O acting as the oxidation agent, and that the effect of H2O under atmospheric pressure reaches a maximum at PH2O–0.7 atm. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 35(8): 527–538, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20139
The effect of long‐term training on police officers' use of open and closed questions in field investigative interviews of children (FIIC)
Authors: Myklebust Trond , Bjørklund Roald A.
Published: November 2006

This study intends to assess the effect of long‐term training on police officers' use of open and closed questions in investigative interviews of children. One hundred field investigative interviews of children were divided into two groups based on the interviewers' level of competence (training and experience). The police officers' questions were classified into groups of either open or closed. In all interviews, the mean numbers were 20 open and 217 closed questions, corresponding to an open–closed question ratio of 1:10. The most competent interviewers used 22 open questions and the less competent used 19 open questions, but the difference was not statistically significant. Analyses of variance (ANOVA) showed a significant effect of question but no main effect of competence. ANOVA revealed a descending number of open questions during the interviews, whilst the distribution of closed questions showed an inverted U distribution with most frequent use of closed questions in the middle part of the interviews. Possible strategies of enhancing the use of open questions are discussed. Copyright © 2006 John Wiley & Sons, Ltd.
Use of shape to distinguish Chamelea gallina and Chamelea striatula (Bivalvia: Veneridae): Linear and geometric morphometric methods
Authors: Rufino Marta M. , Gaspar Miguel B. , Pereira Alexandre M. , Vasconcelos Paulo
Published: November 2006

The commercially fished striped venus clams Chamelea gallina and C. striatula (Bivalvia: Veneridae) are difficult to distinguish by inexperienced observers and the taxonomy of these species is still an issue of discussion. The differences in shape between C. gallina and C. striatula from Portuguese coastal waters were studied through conventional linear and geometric morphometric analysis, using both contour (elliptic Fourier analysis) and landmark‐based methods. The relationships shell length vs. height, width, and total weight were significantly different between species. However, because there was a considerable overlap in the data sets, the species could not be distinguished using any combination of those linear measurements. Geometric morphometric methods provided shape variables that led to 0–6% misclassification rates between species; linear morphometric measures led to 16.8% error. Contour analysis revealed differences primarily in the shell umbo and lunular area. The umbo was more “sharp” and the lunula less pronounced in C. striatula than in C. gallina. Generalized procrustes superimposition (landmark analysis) showed that the main differences between species reside in the length of the pallial sinus. Thus, an index was developed (PI: Pallial Index = pallial sinus length/shell length), which was successfully used to separate the species (with 100% correct classification), i.e., specimens with PI lower than 0.119 belonged to C. gallina, whereas greater PI values were attributed to C. striatula. The use of these geometric morphometric methods allowed the detection of differences in shape between these two species and to develop an easy‐to‐use identification index. We encourage the development of analogous indices that apply the methods of geometric morphometrics to distinguish between other species whose identification is complicated. J. Morphol., 2006. © 2006 Wiley‐Liss, Inc.
Charge dependent behavior of PNA/DNA/PNA triplexes in the gas phase
Authors: Delvolvé Alice , Tabet Jean‐Claude , Bregant Sarah , Afonso Carlos , Burlina Fabienne , Fournier Françoise
Published: November 2006

Intact noncovalent complexes were studied in the gas phase using negative ion nano‐ESI mass spectrometry. Among various noncovalent systems studied in the gas phase, the interaction of DNA strands with peptide nucleic acids (PNAs) presents a strong interest as biologically relevant systems. PNAs originally described by Nielsen are used as DNA mimics as possible medical agents by imprisoning DNA single strands into stable noncovalent complexes. Two types of PNAs were investigated in the PNA/DNA multiplex: the original Nielsen's PNA and a modified backbone PNA by the introduction of syn‐ and anti‐(aminoehtyl)thiazolidine rings. We first investigated the stoichiometry of PNA/DNA multiplexes formed in solution and observed them in the gas phase via qualitative kinetics of complementary strand associations. It resulted in observing PNA2/DNA triplexes (ts) as the multiply deprotonated species, most stable in both the solution and gas phase. Second, charge‐dependant decompositions of these species were undertaken under low‐energy collision conditions. It appears that covalent bond cleavages (base releasing or skeleton cleavage) occur from lower ts charge states rather than ts unzipping, which takes place from higher charge states. This behavior can be explained by considering the presence of zwitterions depending on the charge state. They result in strong salt‐bridge interactions between the positively charged PNA side chain and the negatively charged DNA backbone. We propose a general model to clearly display the involved patterns in the noncovalent triplex decompositions. Third, the relative stability of three PNA2/DNA complexes was scrutinized in the gas phase by acquiring the breakdown curves of their ts6− form, corresponding to the ts unzipping. The chemical structures of the studied PNAs were chosen in order to evidence the possible influence of backbone stereochemistry on the rigidity of PNA2/DNA complexes. It provided significantly different stabilities via Vm measurements. The relative gas‐phase stability order obtained was compared to that found in solution by Chassaing et al., and shows qualitative agreement. Copyright © 2006 John Wiley & Sons, Ltd.
Studies on the metabolism and toxicological detection of the designer drug 2,5‐dimethoxy‐4‐methyl‐β‐ phenethylamine (2C‐D) in rat urine using gas chromatographic/mass spectrometric techniques
Authors: Theobald Denis S. , Maurer Hans H.
Published: November 2006

The phenethylamine‐derived designer drug 2,5‐dimethoxy‐4‐methyl‐β‐phenethylamine (2C‐D) was found to be metabolized in rats by O‐demethylation at position 2 or 5 followed by N‐acetylation or by deamination with oxidation to the corresponding acids or reduction to the corresponding alcohol. Furthermore, 2C‐D was hydroxylated at the methyl group or deaminated followed by reduction to the corresponding alcohol or by oxidation to the corresponding acid. Most of the metabolites were excreted in conjugated form. The authors' systematic toxicological analysis (STA) procedure using full‐scan GC/MS allowed the detection of an intake of a dose of 2C‐D in rat urine that corresponds to a common drug user's dose. Assuming similar metabolism, the described STA procedure should be suitable for proof of an intake of 2C‐D in human urine. Copyright © 2006 John Wiley & Sons, Ltd.
Mathematical Model for Surface‐Initiated Photopolymerization of Poly(ethylene glycol) Diacrylate
Authors: Kızılel Seda , Pérez‐Luna Víctor H. , Teymour Fouad
Published: November 2006

Summary: A general mathematical model has been developed to describe the surface initiated photopolymerization of PEG‐DA forming crosslinked hydrogel membranes upon the surface of a substrate. Such membranes are formed by photopolymerizing a PEG‐DA prepolymer solution by initiation with eosin‐Y‐functionalized surfaces and TEA using VP as accelerator. Experimental measurements of the thickness of hydrogel membranes compare well with the model. The model is developed by using the pseudo‐kinetic approach and the method of moments, and is capable of predicting the crosslink density and thickness of the hydrogel membrane. Parametric sensitivity of the effects of PEG‐DA, VP and coinitiator TEA concentration towards the crosslink density and the thickness of the hydrogel is also investigated. The results obtained for different PEG‐DA and VP concentrations suggest that the concentration ratio of these two monomers is a key parameter in controlling the gel thickness and permeability. This model can also be applied to systems where drugs, proteins or cells are encapsulated through surface initiated photopolymerization to predict the growth and crosslink density profiles of the encapsulating membrane. In a previous study we have experimentally demonstrated that these membranes could be made to attach covalently to the surface of the underlying substrate.

Comparison of experimental measurements and model simulation of PEG‐DA hydrogel membrane thickness versus laser duration at high PEG‐DA concentrations.

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Comparison of experimental measurements and model simulation of PEG‐DA hydrogel membrane thickness versus laser duration at high PEG‐DA concentrations.
Monte Carlo Simulation of Degradation of Porous Poly(lactide) Scaffolds, 1
Authors: Mohammadi Yousef , Jabbari Esmaiel
Published: November 2006

Summary: Monte Carlo method was used to simulate the degradation of porous PLA scaffolds. The simulated volume was assumed to be divided homogeneously between the pore and solid PLA with the ratio equal to the bulk porosity of the scaffold. The volume was divided into surface and bulk elements where the surface elements were in direct contact with the aqueous degradation medium, while the bulk elements were surrounded by the pore and solid PLA. The effect of degradation time on PLA ester groups and carboxylic acid end‐groups for surface and bulk elements, pH, PLA degradation rate and mass loss, and PLA molecular weight distribution was simulated. For surface elements, pH remained constant at 7.4 over the entire time of degradation, while for bulk elements its value decreased significantly to as low as 5.8. The highest drop in pH within the scaffold was observed for the highest porosity of 90%. There was a lag time of at least 7 weeks in the mass loss for surface as well as bulk elements for porosities ranging from 70 to 90%. The mass loss for bulk elements was considerably faster than the surface elements. This difference in the rate of mass loss between the surface and bulk elements could affect the 3D morphology and dimensional stability of the scaffold in vivo as degradation proceeds. The simulation predicts that, due to differences in the rate of bulk and surface degradation, hollow structures could form inside the scaffold after 19, 17, and 15 weeks for initial porosities of 70, 80, and 90%, respectively.

A schematic diagram illustrating the degradation of an element on the outer surface of the scaffold (surface element) versus an element within the volume of the scaffold (bulk element).

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A schematic diagram illustrating the degradation of an element on the outer surface of the scaffold (surface element) versus an element within the volume of the scaffold (bulk element).
Normal and Lateral Deformation of Lyotropically Ordered Polymer Brush
Authors: Polotsky Alexey A. , Birshtein Tatiana M.
Published: November 2006

Summary: Planar polymer brush formed by semirigid chains of freely jointed rigid segments and immersed into a solvent is considered. Brush collapse induced by deterioration of the solvent quality and its deformation by external normal or lateral force is studied. It is demonstrated that these three different situations can be described in the framework of the common approach. It is shown that the collapse is accompanied by liquid‐crystalline (LC) ordering within the brush. The LC transition can be jump‐like (the first order) or continuous, depending on the segment's aspect ratio and grafting density. Transition point is investigated in detail, the corresponding phase diagrams are calculated. It is shown that the phase diagrams of a normally deformed brush have different structures, with a narrow ‘leg’ in the good solvent region for sparsely grafted brush, with two coexistence regions and a triple point, in addition, for shorter segment length or without these features if the chains are densely grafted. For the laterally deformed brush, phase diagrams have similar structures with a critical point in the good solvent regime.

Polymer brush subjected to deformation by normal (top) and lateral (bottom) external force.

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Polymer brush subjected to deformation by normal (top) and lateral (bottom) external force.
Effects of flavonoids on the expression of the pro‐inflammatory response in human monocytes induced by ligation of the receptor for AGEs
Authors: Huang Shang‐Ming , Wu Chi‐Hao , Yen Gow‐Chin
Published: November 2006

Increasing evidence has shown advanced glycation end products (AGEs) receptor ligation (RAGE) to be an important part of complex interactions of the oxidative stress and pro‐inflammatory responses. In this study, flavonoids were used to monitor the protective effects against the oxidative damage and inflammation mediated by AGEs in human monocytes. S100B (RAGE ligand) treatment in human THP‐1 monocytic cells (THP‐1) significantly increased gene expression of the pro‐inflammatory cytokines TNF‐α and IL‐1β; chemokines MCP‐1 and IP‐10; adhesion factors platelet endothelial cell adhesion molecule (PECAM‐1) and β2‐integrin; and pro‐inflammatory cyclooxygenase‐2 (COX‐2). S100B treatment with quercetin and catechin in THP‐1 cells had inhibitory effects on the expression of pro‐inflammatory genes and protein levels. Quercetin and catechin could regulate S100B‐activated oxidant stress‐sensitive pathways through blocking p47phox protein expression. Treatment with quercetin and catechin could eliminate reactive oxygen species (ROS) to reduce oxidative stress stimulated by S100B in THP‐1 cells. Quercetin and catechin also showed different regulatory abilities on mitogen‐activated protein kinase (MAPK) signaling pathways by inhibiting protein expression in S100B‐stimulated inflammatory responses in THP‐1 cells. This study suggests that quercetin and catechin may be of benefit for diabetic vascular complications due to its antioxidant abilities against AGE‐mediated oxidative stress through oxidative stress‐sensitive and oxidative stress‐responsive signaling pathways, which lead to inflammation in human monocytes.
In vitro fermentability of differently digested resistant starch preparations
Authors: Fässler Caroline , Arrigoni Eva , Venema Koen , Brouns Fred , Amadò Renato
Published: November 2006

The in vitro fermentability of two resistant starch preparations type 2 (RS2) and type 3 (RS3) was investigated using human colonic microbiota. Prior to the fermentation experiments, samples were digested using two in vitro models, a batch (ba) and a dynamic (dy), as well as an in vivo method (il) for RS3. Digestion residues were fermented in vitro using a simple batch model lasting 24 h and a more sophisticated dynamic model enduring 72 h. During batch fermentation, metabolite productions and starch degradation rates were similar for RS2 and RS3 but higher for dy‐ compared to ba‐digested samples. RS3il led to the lowest fermentability. Furthermore, increased butyrate ratios were observed for all preparations. The varying RS preparations behaved similarly in the dynamic fermentation but showed high SDs. Moreover, the fermentability was slow during the first 24 h, indicating that the microbiota needed an adaptation period to ferment RS. Propionate ratios increased at the expense of butyrate with exception for RS2dy showing an increase in acetate only. Differences in fermentability observed between the dynamic model, allowing a closer simulation of the in vivo behavior, and the batch model, recommended for screening purposes, could be due to the varying microbiota used.
Effect of lupeol and lupeol linoleate on lipemic – hepatocellular aberrations in rats fed a high cholesterol diet
Authors: Sudhahar Varatharajan , Ashokkumar Sekar , Varalakshmi Palaninathan
Published: November 2006

Cholesterol feeding has been often used to study the etiology of hypercholesterolaemia‐related metabolic disturbances. The aim of the present study is to investigate the effects of a pentacyclic triterpene, lupeol, and its ester derivative on hepatic abnormalities associated with hypercholesterolemic rats. Hypercholesterolaemia was induced in male Wistar rats by feeding them with a high cholesterol diet (HCD) containing normal rat chow supplemented with 4% cholesterol and 1% cholic acid, for 30 days. Lupeol and lupeol linoleate were supplemented (50 mg/kg body wt/day) during the last 15 days. Increased hepatic lipid profile along with abnormalities in lipid‐metabolizing enzyme activities were seen in hypercholesterolemic rats. An apparent increase in the expression of Acyl‐CoA cholesterol acyltransferase mRNA was seen in HCD fed rats. The activities of hepatic marker enzymes, which serve as indices of cellular injury, were altered in HCD fed rats. Treatment with triterpenes significantly modulated the abnormalities induced by hypercholesterolaemia. Also, an increased (P >0.001) faecal excretion of cholesterol and bile acids were observed in lupeol and lupeol linoleate group when compared with HCD fed group. Therefore, it can be concluded that triterpenes treatment afforded substantial protection against the anomalies, which are manifested during the early stage of hypercholesterolemic atherogenesis.
Analysis of sphingolipids in potatoes (Solanum tuberosum L.) and sweet potatoes (Ipomoea batatas (L.) Lam.) by reversed phase high‐performance liquid chromatography electrospray ionization tandem mass spectrometry (HPLC‐ESI‐MS/MS)
Authors: Bartke Nana , Fischbeck Anne , Humpf Hans‐Ulrich
Published: November 2006

Ceramides and glucocerebrosides of potatoes (Solanum tuberosum L.) and sweet potatoes (Ipomoea batatas (L.) Lam.) were analyzed using RP‐HPLC‐ESI‐MS/MS. Ceramides and glucocerebrosides containing the three different long‐chain bases 4,8‐sphingadienine (d18:2Δ4,Δ8), 4‐hydroxy‐8‐sphingenine (t18:1Δ8), and 8‐sphingenine (d18:1Δ8) acylated to saturated and unsaturated hydroxy‐ and nonhydroxy fatty acids with 16–26 carbon atoms were detected. For ceramides and glucocerebrosides 4,8‐sphingadienine (d18:2Δ4,Δ8) was found as the major long‐chain base, with lesser amounts of 4‐hydroxy‐8‐sphingenine (t18:1Δ8) and 8‐sphingenine (d18:1Δ8). 2‐(α‐)Hydroxypalmitic acid (C16:0h) was the major fatty acid, which was found to be acylated to the long‐chain bases. For quantification of these compounds, an RP‐HPLC‐ESI‐MS/MS method with an “echo‐peak”‐technique simulating internal standard injection was developed. The analyzed samples of potatoes and sweet potatoes showed amounts of ˜0.1–8 μg/kg single ceramides and amounts up to 500 μg/kg glucocerebrosides, with C16:0h‐glucosyl‐4,8‐sphingadienine as the major component.
Robust fault estimation approach and its application in vehicle lateral dynamic systems
Authors: Gao Z. , Ding S. X. , Ma Y.
Published: November 2006

For state‐space systems with unknown process disturbances, a robust state‐space observer is designed to simultaneously estimate the system state, the finitely times derivatives of the fault, and the fault signal. The considered fault signal can be allowed to be unbounded provided its finitely times derivative is bounded. A numerical example is given to illustrate the design procedure. Vehicle lateral dynamic system plays an important role in the vehicle manoeuverability, stability and driving safety. An application example with the real data for the vehicle lateral dynamic system is finally provided to demonstrate the efficiency of the present estimation technique. Copyright © 2006 John Wiley & Sons, Ltd.
Current analytical methods to study plant water extracts: the example of two mushrooms species, Inonotus hispidus and Sparassis crispa
Authors: Politi Matteo , Silipo Alba , Siciliano Tiziana , Tebano Marianna , Flamini Guido , Braca Alessandra , Jiménez‐Barbero Jesús
Published: November 2006

The analytical study of two hot‐water extracts from the mushrooms Inonotus hispidus (Bull.) P. Karst and Sparassis crispa Wulf.:Fr was performed by NMR, HPLC‐PAD‐MS and GC‐MS. The simultaneous use of different analytical techniques highlighted the diverse classes of natural products contained in these extracts. This study describes an attempt to adapt a useful phytochemical method to the direct investigation of plant water extracts, which represent the typical traditional manner for the administration of natural remedies. The heritage concerning plant processing procedures, known as traditional pharmaceutical knowledge, could play an important role in future research on medicinal species. This kind of study could be used as an update for current and future perspectives in this research field. Copyright © 2006 John Wiley & Sons, Ltd.
Identification of isoflavone glycosides in Pueraria lobata cultures by tandem mass spectrometry
Authors: Prasain Jeevan K. , Reppert Adam , Jones Kenneth , Moore II D. Ray , Barnes Stephen , Lila Mary Ann
Published: November 2006

Isoflavones in the methanolic extracts of kudzu (Pueraria lobata) callus, suspension and root cultures were compared in order to develop an experimental system in which puerarin (daidzein 8‐C‐glucoside) and other isoflavones could be synthesised in vitro. Quantitative variation of puerarin and other known isoflavones was estimated in kudzu culture extracts using HPLC‐UV. The highest and lowest amounts of puerarin (14.56 and 0.33 mg/g) were present in in vitro root cultures and leaf tissue‐derived callus cultures, respectively. A total of 48 isoflavone metabolites were detected in extracts of kudzu root cultures by HPLC‐MS/MS, and the structures of 33 of them were tentatively assigned. Amongst these, 12 isoflavone C‐glycosides were identified. Hydroxy‐derivatives of puerarin in several isomeric forms were detected, some of which have not been previously reported in kudzu root. The molecular weights, interpretation of characteristic fragment ions obtained from HPLC‐MS/MS and comparison with reported data allowed the putative identification of the isoflavone metabolites. Copyright © 2006 John Wiley & Sons, Ltd.
Preparation of polystyrene/polyaniline core/shell structured particles and their epoxy‐based conductive composites
Authors: Wang Yangyong , Jing Xinli
Published: November 2006

Polyaniline (PANI) was synthesized by chemical oxidative polymerization of aniline (ANI) in the presence of sulfonated crosslinked polystyrene (SCPS) particles in neutral water. The polymerization of ANI occurred preferentially on the surfaces of the SCPS particles, resulting in core/shell structured SCPS/PANI particles. The conductivities of the SCPS/PANI particles increased with increasing degree of sulfonation of the SCPS and with increasing ANI/SCPS weight ratios in the reactants. Conductive epoxy‐based composites were prepared by curing the blend of SCPS/PANI particles and epoxy resin with an aromatic amine curing reagent, indicating the core/shell structured particles were stable, to some extent, to alkaline environments, which will be of significant importance for the practical application of PANI in many cases. Copyright © 2006 Society of Chemical Industry
Surface tension of poly(ester urethane)s and poly(ether urethane)s
Authors: Lupu Mihaela , Macocinschi Doina , Ioanid Ghiocel , Butnaru Maria , Ioan Silvia
Published: November 2006

The correlation between the surface tension parameters and the chemical composition of poly(ester urethane) and poly(ether urethane) thin films with different soft and hard segments, both before and after plasma treatment, was investigated. Calculations are based on the geometric mean approach of Owens and Wendt (Owens DK and Wendt RC, J Appl Polym Sci 13:1741 (1969)), Rabel (Rabel W, Physikalische Blätter 33:151 (1977)) and Kälble (Kälble DH, J Adhesion 1:102 (1969)), on the Lifshitz–van der Waals acid/base approach of van Oss and co‐workers (van Oss CJ, Good RJ and Chaudhury MK, Langmuir 4:884 (1988); van Oss CJ, Ju L, Chaudhury MK and Good RJ, Chem Rev 88:927 (1988); van Oss CJ, Interfacial Forces in Aqueous Media. Marcel Dekker, New York (1994)) and on the theoretical methods involving quantitative structure–property relationships (Bicerano J, JMS Rev Macromol Chem Phys C36:161 (1996)). For all investigated films, the polar terms contribute significantly to the total surface tensions, as due to the large electron donor, $\gamma_{\rm {sv}}^{-}$, interactions. Plasma treatment alters the surface energy of samples by changing their surface polarity and hydrophilicity. The hydrophilicity trends for polyurethanes were also studied by means of the free energy of hydration between compounds and water. Preliminary blood contact tests of the selected polyurethane sample with higher hydrophilicity were developed for biomedical applications. Copyright © 2006 Society of Chemical Industry
Dimensionally and thermally stable polymer, containing disordered graphitic structure and adamantane
Authors: Burnham Kikue S. , Roth Robert , Zhou Faith , Fan Wenya , Brouk Emma , Stifanos Mehari
Published: November 2006

In an attempt to develop a low‐k interlayer dielectric, adamantane‐diphenyldiethynyl moiety containing oligomer is prepared. Oligomerization of 1,3,5,7‐tetrakis[3/4‐ethynylphenyl]adamantane (4) is accomplished by a Glaser–Hay oxidative coupling with 1,3,5‐triethynylbenzene and phenylacetylene end‐capping agent. The CHCl3 soluble oligomer is then thermally treated by step‐curing at 200, 300, 380, and 450 °C for 30 min at each temperature under nitrogen flow to render a shiny void‐free black polymer. TGA analysis indicates that the polymer is stable under nitrogen up to 500 °C with a marginal decomposition up to 800 °C. Solid‐state 13C NMR, Raman scattering, and FTIR are used to characterize the structure of the polymer. The polymer consists of amorphous carbon networks with the adamantane moieties and nanosized graphitic regions (clusters), which are generated from the thermal crosslinking of the diphenyldiethynyl units. It shows a remarkably low linear coefficient of thermal expansion (∼25 ppm/°C), presumably due to the presence of the disordered graphitic structure. Its high density (∼1.21 g/cm3), refractive index (∼1.80 at 632 nm), and Young's modulus (∼17.0 GPa) are also consistent with the interpretation. This study reveals important details about the effect of microscopic structure on the macroscopic properties of the highly crosslinked polymer. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6909–6925, 2006
Copolymerizations of ethylene and polar comonomers with bis(phenoxyketimine) group IV complexes: Effects of the central metal properties
Authors: Zhang Xiaofan , Chen Shangtao , Li Huayi , Zhang Zhicheng , Lu Yingying , Wu Chunhong , Hu Youliang
Published: November 2006

With triisobutylaluminum as a protection reagent, copolymerizations of ethylene with 10‐undecen‐1‐ol, 10‐undecenoic acid, and 5‐hexen‐1‐ol have been performed with bis[(3,5‐di‐tBuC6H22‐O)PhCN(2‐FC6H4)]ZrCl2 (a)/methylaluminoxane or bis[(3,5‐di‐tBuC6H22‐O)PhCN(2‐FC6H4)]TiCl2 (b)/methylaluminoxane as the catalyst. Both catalysts exhibit high activities of copolymerization in the presence of polar groups. The properties of the copolymers are strongly affected by the central metal properties of the catalysts. In comparison with complex a, titanium complex b appears to be less sensitive to polar monomers and more favorable for the preparation of higher molecular weight functionalized polyethylenes containing higher contents of polar groups. Studies on the polymerization temperature indicate that the catalytic activities decrease greatly with both complex a and complex b. The comonomer contents incorporated into the copolymers are slightly dependent on the polymerization temperature in the case of complex a, whereas in the case of complex b, the effect of the polymerization temperature is more distinct: an increase in the polymerization temperature can efficiently facilitate the incorporation of polar comonomers. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 59–68, 2007
Poly(ethylene glycol)‐b‐phosphorylated polyglycidols as CaCO3 crystal growth modifiers. II. Macromolecular architecture versus the crystal size and shape and crystallization inhibition
Authors: Kaluzynski K. , Pretula J. , Penczek S.
Published: November 2006

Ionic–nonionic dihydrophilic block copolymers with poly(ethylene glycol) as nonionic blocks and phosphorylated polyglycidol as ionic blocks of various lengths and various degrees of phosphorylation were prepared. The influence of these variables on the CaCO3 crystal structure and the inhibition of crystal growth was studied. The best results (small crystal size, low dispersity of sizes, and longest inhibition time) were observed for limited degrees of phosphorylation. A certain part of the dihydrophilic block copolymers was permanently bound to the formed particles, opening a way to the synthesis of inorganic–organic (polymer) hybrids based on these components. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 90–98, 2007
Similarities between polyelectrolyte gels and biopolymer solutions
Authors: Horkay Ferenc , Hecht Anne‐Marie , Geissler Erik
Published: November 2006

Small angle neutron scattering (SANS) measurements and osmotic swelling pressure measurements are reported for polyelectrolyte gels and solutions under nearly physiological conditions. A synthetic polymer (sodium‐polyacrylate) and three biopolymers (DNA, hyaluronic acid, and polyaspartic acid) are studied. The neutron scattering response of these anionic polyelectrolytes is closely similar, indicating that at larger length scales the organization of the polymer molecules is not significantly affected by the fine details of the molecular architecture (e.g., size and chemical structure of the monomer unit, type of polymer backbone). The results suggest that specific interactions between the polyelectrolyte chains and the surrounding monovalent cations are negligible. It is found that the osmotic compression modulus of these biopolymer solutions determined from the analysis of the SANS response decreases with increasing chain persistence length. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3679–3686, 2006
Phase equilibria and phase separation dynamics in a polymer composite containing a main‐chain liquid crystalline polymer
Authors: Kim Do , Kyu Thein , Hashimoto Takeji
Published: November 2006

Various topological phase diagrams of blends of main‐chain liquid crystalline polymer (MCLCP) and flexible polymer have been established theoretically in the framework of Matsuyama–Kato theory by combining Flory–Huggins (FH) free energy for isotropic mixing, Maier–Saupe (MS) free energy for nematic ordering in the constituent MCLCP, and free energy pertaining to polymer chain‐rigidity. As a scouting study, various phase diagrams of binary flexible polymer blends have been solved self‐consistently that reveal a combined lower critical solution temperature (LCST) and upper critical solution temperature (UCST), including an hourglass phase diagram. The calculated phase diagrams exhibit liquidus and solidus lines along with a nematic–isotropic (NI) transition of the constituent MCLCP. Depending on the strengths of the FH interaction parameters and the anisotropic (nematic–nematic) interaction parameters, the self‐consistent solution reveals an hourglass type phase diagram overlapping with the NI transition of the constituent MCLCP. Subsequently, thermodynamic parameters estimated from the phase diagrams hitherto established have been employed in the numerical computation to elucidate phase separation dynamics and morphology evolution accompanying thermal‐quench induced phase separation of the MCLCP/polymer mixture. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3621‐3630, 2006
Production of an Atmospheric‐Pressure Glow Discharge Using an Inductive Energy Storage Pulsed Power Generator
Authors: Takaki Koichi , Kirihara Hidekazu , Noda Chiharu , Mukaigawa Seiji , Fujiwara Tamiya
Published: November 2006

Summary: An atmospheric‐pressure glow discharge has been generated using an inductive energy storage pulsed power generator. A pulsed high voltage with a short rise time of under 30 ns is employed to generate streamer discharges simultaneously at all tips of a needle‐array electrode in nitrogen. The large number of streamer discharges prevent glow‐to‐arc transitions caused by inhomogeneous thermalization. SOS diodes are used as an opening switch to shorten the rise time. Circuit parameters such as the capacitance of a primary energy storage capacitor and/or the inductance of a secondary energy storage inductor are determined by experimental results using dummy resistive loads. The results show that circuit parameters adequate for producing atmospheric glow discharges are different from those for producing corona discharges. The energy transfer efficiency of the pulsed power generator has a maximum value of 75% at 193 Ω dummy load resistance. Voltage‐current characteristics of the glow discharge show two regions: constant voltage (normal glow) and an increasing voltage with discharge current (abnormal glow). The glow current is drastically decreased by eliminating the SOS diodes, in which case the charging voltage is directly applied to the electrode. Spatial‐ and time‐averaged electron densities in a positive column are estimated from calculations based on nitrogen swarm data. The electron density is estimated to be 1.8 × 1011 cm−3, which is much larger than 9.7 × 109 cm−3 in the case without the SOS diodes.

Photographs of atmospheric pressure nitrogen glow discharge generated using a needle‐array electrode at a 1.0 cm gap length.

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Photographs of atmospheric pressure nitrogen glow discharge generated using a needle‐array electrode at a 1.0 cm gap length.
Organophosphate resistance in olive fruit fly, Bactrocera oleae, populations in Greece and Cyprus
Authors: Skouras Panagiotis J , Margaritopoulos John T , Seraphides Nicos A , Ioannides Ioannis M , Kakani Evi G , Mathiopoulos Kostas D , Tsitsipis John A
Published: November 2006

The olive fruit fly Bactrocera oleae (Gmelin) (Diptera: Tephritidae) is the most important pest of olives in countries around the Mediterranean basin. Its control has been based mostly on bait sprays with organophosphate insecticides (usually dimethoate or fenthion) for about 40 years. In the present study, the resistance status of olive fruit fly populations to dimethoate was examined in Greece and Cyprus over 2 years. Thirty‐one populations from various regions of Greece, nine from Cyprus and one laboratory susceptible strain, which served as a control, were assayed by topical application of dimethoate. Considerable variation in the resistance levels to dimethoate was recorded in the populations of B. oleae, with resistance ratios ranging from 6.3 to 64.4 (ED50 values 12.5–128.7 ng dimethoate per insect). The highest resistance ratios were found in populations from Crete, and the lowest in those from Cyprus. This variation could be attributed to different selection pressures from insecticidal applications among populations from the various regions. Migration of resistant genotypes, either autonomous or via commerce, may also be involved. Copyright © 2006 Society of Chemical Industry
Enhancement of the biological activity of nucleopolyhedrovirus through disruption of the peritrophic matrix of insect larvae by chlorfluazuron
Authors: Guo Hui‐Fang , Fang Ji‐Chao , Liu Bao‐Sheng , Wang Jie‐Ping , Zhong Wan‐Fang , Wan Fang‐Hao
Published: November 2006

The enhancement of Spodoptera litura (F.) nucleopolyhedrovirus (SlNPV) activity using the chitin synthesis inhibitor chlorfluazuron was investigated. When tested against fifth‐instar S. litura larvae, chlorfluazuron produced synergistic effects at doses of 0.05 and 0.025 µg per insect, and additive effects at doses of 0.1 and 0.2 µg. Furthermore, the time required for SlNPV to kill larvae was significantly reduced by chlorfluazuron at all doses tested. The activity and killing speed of Autographa californica (Spey) nucleopolyhedrovirus (AcMNPV) against third‐instar Spodoptera exigua (Hübner) larvae were similarly improved by chlorfluazuron at a dose of 0.05 µg per larva. Furthermore, the growth of S. exigua was significantly retarded by chlorfluazuron. Environmental scanning electron microscopy (ESEM) showed that the peritrophic matrices (PMs) of S. litura exposed to chlorfluazuron alone, or the combination treatment, were markedly disrupted. Obvious ruptures on the outer surfaces of the PM were observed, which potentially facilitated the passage of virions through the matrix. Copyright © 2007 Society of Chemical Industry