bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of a new photoreactive gelatin with BTDA and HEMA derivatives
Authors: Ding Fan‐Chun , Hsu Shan‐hui , Chiang Wen‐Yen
Published: April 2008

A novel bio‐affinitive, photocuring, and membrane‐forming gelatin derivative was synthesized in this study. This process was based on the amide formation between carboxylic acid and the amine in methanol–water media using dicyclohexyl‐carbodiimide (DCC) as a condenser. Gelatin and glycine were the sources of amine in the model reaction. Since there were two anhydride groups in each 3,3′,4,4′‐benzophenone tetra‐carboxylic dianhydride (BTDA) molecule, two 2‐hydroxyethyl methacrylate (HEMA) molecules were used to induce the ring‐opening reaction of BTDA and release two carboxylic acid groups. The resulting photoreactive gelatin was called GE‐BTHE, of which the photoreactive component was the ketone groups of BTDA and HEMA that played the role of double bond supplier. This photoreactive gelatin could be converted from the transparent liquid phase into swollen membrane by a 6‐min irradiation of high pressure mercury lamp. The most efficient irradiation was at 267 nm and the highest degree of swelling of the cured GE‐BTHE membrane could reach 5.9. The elongation from the dried gel remained 5–10%, i.e., relatively elastic. The properties of this gelatin derivative were investigated using amide formation analysis, calculation of the gel content and the swelling ratio, and monitoring of the photocuring process. The GE‐BTHE synthesized in this study should be very potential in applications such as protective wound dressings and hemostatic absorbents for minimally invasive surgery. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Thermal expansion of fumed silica/cyanate ester nanocomposites
Authors: Goertzen William K. , Kessler M. R.
Published: April 2008

The thermal expansion behavior of a cyanate ester matrix reinforced by fumed silica nanoparticles with average primary particle diameters of 12 and 40 nm was investigated with thermomechanical analysis. All nanocomposites showed decreased coefficients of thermal expansion (CTEs) in comparison with the neat bisphenol E cyanate ester resin, but the 12‐nm fumed silica nanocomposites had lower CTEs than the 40‐nm nanocomposites for equal volume fractions. The largest decrease in CTE was 27.0% for 20.7 vol % 40‐nm fumed silica. When the data were compared to applicable theory, the best fit of the data was given by Schapery's upper limit and Shi's model. Estimates of the interphase volume fraction and effective thickness surrounding the nanoparticles were made with the results of Shi's model, and the results showed that the interphase volume fraction was larger for the 12‐nm fumed silica nanocomposites, given an equal fraction of silica. The glass‐transition temperature of the nanocomposites from thermomechanical analysis varied only slightly with the volume fraction. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis of pH dependent chitosan‐EPI hydrogel films and their application for in vitro release of promethazine hydrochloride
Authors: Seki Yoldaş , Yurdakoc Kadir
Published: April 2008

Chitosan‐epichlorohydrin hydrogel films (ChitEPI) were synthesized by using chitosan in the presence of epichlorohydrin (EPI) as a crosslinking agent at various amounts. SEM, FTIR, TGA, and DSC analysis were conducted for the characterization of the hydrogels. The DSC measurements indicate that ChitEPI hydrogels did not exhibit better thermal stability when compared to chitosan. Swelling behavior of Chitosan‐EPI hydrogel film is pH dependent and showed a reversible swelling behavior with a fast response. The hydrogels were used for in vitro release of promethazine hydrochloride (PHCl) in pH = 1.2 and pH = 7.4 phosphate buffer solutions (PBS). The release of PHCl synthesized from hydrogels at pH = 7.4 is quite low while at pH = 1.2, the highest value was observed as 49% for ChitEPI600. It has been also found that PHCl release from ChitEPI thin films is mainly controlled by diffusion control mechanism. ChitEPI hydrogels may be used for the delivery of drug in stomach and gastrointestinal tract. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Comparative study of silica‐, nanoclay‐ and carbon black‐filled EPDM rubbers
Authors: Tan Haisheng , Isayev Avraam I.
Published: April 2008

Silica‐, nanoclay‐, and carbon black (CB)‐filled ethylene–propylene–diene terpolymer (EPDM) mixtures were prepared and subsequently vulcanized. Rheological properties and cure characteristics of the mixtures and mechanical properties of vulcanizates were measured. Rheological property measurements indicated the storage modulus, loss modulus, and complex dynamic viscosity of silica‐filled EPDM mixtures were much higher than those of CB‐filled EPDM mixtures while tan δ values were lower. The optimum cure time of silica‐ and nanoclay‐filled EPDM mixtures increased with filler loading, whereas the values for CB‐filled mixtures slightly decreased with loading. The hardness, modulus, elongation at break, and tensile strength of all the vulcanizates increased with increasing filler loading. The elongation at break of CB‐filled EPDM vulcanizates increased insignificantly with CB loading. Among the three fillers, the increase of the tensile strength and elongation at break was most significant for silica‐filled EPDM vulcanizates. Remarkably, for 30 phr silica‐filled EPDM vulcanizates, a tensile strength and elongation at break of 23.5 MPa and 1045% was achieved, respectively. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Poly(ethylene terephthalate) nanocomposite fibers with functionalized multiwalled carbon nanotubes via in‐situ polymerization
Authors: Mun Sung Jin , Jung Young Mee , Kim Jeong‐Cheol , Chang Jin‐Hae
Published: April 2008

Poly(ethylene terephthalate) (PET) hybrids with newly synthesized functionalized multiwalled carbon nanotubes (MWNTs) were obtained by carrying out the in situ polycondensation of ethylene glycol with dimethyl terephthalic acid. The PET hybrids were melt‐spun to produce monofilaments with various functionalized MWNT contents and draw ratios (DRs). The thermomechanical properties and morphologies of the PET hybrid fibers were determined using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), wide angle X‐ray diffraction (XRD), electron microscopy (SEM and TEM), and a universal tensile machine (UTM). The XRD analysis and TEM micrographs show that the levels of nanosize dispersion can be controlled by varying the MWNT content. It was found that the addition of only a small amount of functionalized MWNTs was sufficient to improve the properties of the PET hybrid fibers. The maximum enhancement in the ultimate tensile strength was found to arise at a functionalized MWNT content of 0.5 wt %. However, the initial modulus was found to increase linearly with increases in the functionalized MWNT loading from 0 to 1.5 wt %. The thermal properties and conductivities of the PET hybrid fibers were found to be better than those of pure PET fibers. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
A rheological study of the ageing of emulsion and microsuspension‐based PVC plastisols
Authors: Barroso Eva G. , Duarte Fernando M. , Couto Miguel , M. Maia João
Published: April 2008

A PVC plastisol is a homogeneous dispersion of PVC resin in a liquid continuous phase consisting basically of a plasticizer and a thermal stabilizer; the PVC resin being usually a fine powder is polymerized by emulsion or microsuspension processes. Plastisol rheology is affected by many aspects of the plastisol formulations, such as type and amount of each ingredient, the mixing procedure, temperature, and the effect of PVC resin properties. In this work, the ageing behavior of PVC plastisols with different resin types was studied, with the results showing an unexpected behavior in the elastic modulus, probably originating from plasticizer adsorption at the surface of the PVC particles. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Overexpression of JKTBP1 induces androgen‐independent LNCaP cell proliferation through activation of epidermal growth factor‐receptor (EGF‐R)
Authors: Wu Yong‐Yang , Li Hong , Lv Xiao‐Yan , Wei Qiang , Li Xiang , Liu Xin‐Yu , Zhou Qin , Wei Yu‐Quan
Published: April 2008

Heterogenous nuclear ribonucleoprotein D‐like protein (JKTBP) belongs to a new member of hnRNPs. Previous studies implied that JKTBP1 may be associated with the progression of androgen‐independent (AI) prostate cancer. In this study, we generated three stable LNCaP cell lines which expressed exogenous JKTBP1. Furthermore, the effect of ectopic JKTBP1 on the proliferation of LNCaP cells and its mechanism was investigated. We originally found that the ectopic JKTBP1 expression resulted in the proliferation of LNCaP cells in an AI way, as well as inducing the upregulated expression of EGF‐R and prostate‐specific antigen (PSA), but did not influence the expression level of AR. Moreover, AG1478 suppressed the effect of proliferation induced by JKTBP1. In addition, immunohistochemistry showed that JKTBP1 expression was significantly elevated in AI prostate cancer tissues when compared with the androgen‐dependent (AD) prostate cancer and benign prostatic hyperplasia. Our data indicated that overexpression of JKTBP1 in LNCaP cells leads to abnormal cell proliferation and may be involved in the process of AD to AI through induction of EGF‐R expression. Copyright © 2008 John Wiley & Sons, Ltd.
Polyelectrolyte‐Induced Self‐Assembly of Positively Charged Alkynylplatinum(II)–Terpyridyl Complexes in Aqueous Media
Authors: Yu Cong , Chan Kenneth Hoi‐Yiu , Wong Keith Man‐Chung , Yam Vivian Wing‐Wah
Published: April 2008

Polyelectrolytes carrying multiple negative charges were found to induce the aggregation and self‐assembly of the positively charged platinum(II)–terpyridyl complexes in aqueous media. The aggregation and self‐assembly of the complexes were driven by electrostatic interactions between the polymer and the complex, and by terpyridine ligand π–π stacking and platinum–platinum (metal–metal) interactions. As a result, remarkable UV/Vis and emission spectral changes were observed. The spectroscopic property changes were related to the structural properties of the metal complexes as well as the polyelectrolytes. The induced self‐assembly of the platinum complexes was also strongly affected by the solution properties of the aqueous media, for example, the solution pH, ionic strength, and the percentage of organic solvent added.
α‐Aminophosphonates as novel organocatalysts for asymmetric Michael addition of carbonyl compounds to nitroolefins
Authors: Tao Qin , Tang Guo , Lin Kan , Zhao Yu‐Fen
Published: April 2008

A cyclic α‐aminophosphonate was found to be a novel organocatalyst for Michael type addition reactions of carbonyl compounds to nitroolefins to afford the corresponding adducts in high enantio‐ and diastereoselectivities. Chirality, 2008. © 2008 Wiley‐Liss, Inc.
Synthesis and application of chiral β‐amino disulfides as ligands for the enantioselective addition of diethylzinc to aldehydes
Authors: Braga Antonio L. , Galetto Fábio Z. , Rodrigues Oscar E. D. , Silveira Claudio C. , Paixão Marcio W.
Published: April 2008

A new class of chiral β‐amino disulfides was synthesized from readily available and inexpensive starting materials by a straightforward method and their abilities as ligands were examined in the enantioselective addition of diethylzinc to aldehydes. Enantiomeric excesses of up to 99% have been obtained using 0.5 mol % of the chiral catalysts. Chirality, 2008. © 2008 Wiley‐Liss, Inc.
Highly enantioselective synthesis, crystal structure, and circular dichroism spectroscopy of (R)‐bambuterol hydrochloride
Authors: Cao Gao , Hu Ai‐Xi , Zou Kang‐Sheng , Xu Ling , Chen Jian‐Long , Tan Wen
Published: April 2008

The present article describes the asymmetric synthesis of (R)‐bambuterol hydrochloride based on 1‐(3,5‐dihydroxyphenyl)ethanone as starting material, which was esterified by dimethylcarbamic chloride, and brominated by copper (II) bromide. Then the carbonyl group was reduced efficiently using (−)‐B‐chlorodiisopinocamphenylborane [(−)‐DIP‐chloride™] as an asymmetrical reducing agent. Followed by epoxide ring closure with NaOH and ring expansion with tert‐butylamine led to the desired product (R)‐bambuterol with e.e. up to 99%. The optical properties and absolute configuration of (R)‐bambuterol hydrochloride were further investigated using circular dichroism spectroscopy and X‐ray single crystal analysis. Chirality, 2008. © 2008 Wiley‐Liss, Inc.
Chiral recognition via helical sense and phase in a crystalline supramolecular array of intermeshed triple‐helices
Authors: Glaser Robert
Published: April 2008

Hexatertiary butyl‐substituted D3‐symmetrical cage ligands composed of octahedral bidentate complexes of Ni(II) or Cu(II) ligated on either side to triskelion arrangements of three salicyl rings bound to a central nitrogen hub atom exhibit triple‐helical conformations. Maximization of intermolecular aromatic–aromatic interactions between these complexes promote extended tongue and groove interleaving and affords a supramolecular array of diastereomeric intermeshed C3‐symmetrical triple‐helices perpetuating sideways throughout alternating enantiomeric layer stacks in the entire P‐3 space group crystal lattice. Chiral recognition within these supramolecular ensembles is based upon the principles of helical sense and phase. A discussion of the symmetry, mechanical and chemical factors, and constraints influencing the formation of these self‐assembled crystalline supramolecular ensembles will be presented. Chirality, 2008. © 2008 Wiley‐Liss, Inc.
High‐dimensional model representation for structural reliability analysis
Authors: Chowdhury Rajib , Rao B. N. , Prasad A. Meher
Published: April 2008

This paper presents a new computational tool for predicting failure probability of structural/mechanical systems subject to random loads, material properties, and geometry. The method involves high‐dimensional model representation (HDMR) that facilitates lower‐dimensional approximation of the original high‐dimensional implicit limit state/performance function, response surface generation of HDMR component functions, and Monte Carlo simulation. HDMR is a general set of quantitative model assessment and analysis tools for capturing the high‐dimensional relationships between sets of input and output model variables. It is a very efficient formulation of the system response, if higher‐order variable correlations are weak, allowing the physical model to be captured by the first few lower‐order terms. Once the approximate form of the original implicit limit state/performance function is defined, the failure probability can be obtained by statistical simulation. Results of nine numerical examples involving mathematical functions and structural mechanics problems indicate that the proposed method provides accurate and computationally efficient estimates of the probability of failure. Copyright © 2008 John Wiley & Sons, Ltd.
Cre reporter mouse expressing a nuclear localized fusion of GFP and β‐galactosidase reveals new derivatives of Pax3‐expressing precursors
Authors: Stoller Jason Z. , Degenhardt Karl R. , Huang Li , Zhou Diane D. , Lu Min Min , Epstein Jonathan A.
Published: April 2008

A new Cre‐reporter strain of mouse has been developed that expresses a fusion protein derived from the lacZ gene fused to GFP with a nuclear localization signal. This construct is expressed from the ROSA26 locus upon Cre‐mediated recombination that removes a loxP‐flanked PGK‐neo cassette, thus allowing for detection of Cre activity in all tissues. This reporter strain, which is similar to prior R26R and R26EGFP strains, has certain advantages related to the nuclear expression and the combined expression of both β‐galactosidase and GFP activities. We show that the use of this newly developed reporter line allows for enhanced resolution, detection and co‐localization. Thus, we report a previously unrecognized subset of venous endothelial cells derived from Pax3 expressing precursors. genesis 46:200–204, 2008. © 2008 Wiley‐Liss, Inc.
Heterocyclic Quinol‐Type Fluorophores: Solid‐State Fluorescence Change in Crystals of Benzo[b]naphtho[1,2‐d]furan‐6‐one‐Type Fluorophore upon Inclusion of Organic Solvent Molecules
Authors: Ooyama Yousuke , Yoshida Katsuhira
Published: April 2008

The crystals of benzo[b]naphtho[1,2‐d]furan‐6‐one‐type fluorophores (1) exhibit sensitive colour and fluorescence change upon enclathration of organic solvent molecules. The crystal of fluorophore 1b (R = Bu) exhibits fluorescence decrease upon inclusion of cyclohexane; however, the crystal of fluorophore 1c (R = Ph) exhibits a drastic fluorescence enhancement upon inclusion of chloroform. To elucidate the enclathrated guest effects on the photophysical properties of the crystals, the X‐ray crystal structures of the guest‐free and guest‐inclusion compounds were determined. On the basis of the spectroscopic data and the crystal structures, the effects of the enclathrated guest on the solid‐state photophysical properties of the clathrate compounds are discussed.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Synthesis of Porphyrin–Fullerene Dyads and Their Spectroscopic Properties
Authors: Leupold Stephan , Shokati Touraj , Eberle Christoph , Borrmann Tobias , Montforts Franz‐Peter
Published: April 2008

Porphyrin–fullerene dyads with different linkages between the two subunits were synthesized for mimicking photosynthesis. NMR spectra and quantum mechanical calculations show special structural features that should influence light‐induced electron transfer of the photosynthetic process. Starting point of the synthetic routes is a deuterioporphyrin dimethyl ester prepared from the readily accessible blood pigment heme. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Spirocyclic Pyridoazepine Analogues of Galanthamine: Synthesis, Modelling Studies and Evaluation as Inhibitors of Acetylcholinesterase
Authors: Vanlaer Sofie , De Borggraeve Wim M. , Voet Arnout , Gielens Constant , De Maeyer Marc , Compernolle Frans
Published: April 2008

Spirocyclic pyridoazepines, designed as simplified analogues of the alkaloid galanthamine, were synthesised and evaluated as inhibitors of acetylcholinesterase. The key cyclisation step involved internal displacement of 2‐chloro or 2‐iodopyridine by either nucleophilic aromatic substitution or a Heck reaction. The target compounds showed significant inhibition of acetylcholinesterase but lower than that of galanthamine. This result could be rationalised by comparative docking simulation studies based on the known crystal structure of the acetylcholinesterase–galanthamine complex; multiple hydrogen bonding of a cocrystallised water molecule to both the receptor and the ligand was found to be of crucial importance for effective binding to the active site of the enzyme. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Effects of Divalent Metal Ions on Electrochemiluminescence Sensor with Ru(bpy)32+ Immobilized in Eastman‐AQ Membrane
Authors: Yuan Jipei , Wang Erkang
Published: April 2008

Different effects of divalent metal ions on electrochemiluminescence (ECL) sensor with Ru(bpy)32+ immobilized in Eastman‐AQ membrane were investigated. Mg2+, Ca2+ and Fe2+ can elevate the ECL of Ru(bpy)32+/proline; while metal ions that underwent redox reactions on the electrode such as Mn2+ and Co2+ presented intensive quenching effects on Ru(bpy)32+ ECL. Also, the quenching effect of Mn2+ on the ECL sensor with Ru(bpy)32+ immobilized in Eastman‐AQ membrane enhanced to about 30‐folds compared with the case that Ru(bpy)32+ was dissolved in phosphate buffer, and the enhanced quenching effects of Mn2+ were studied.
Pseudo‐dynamic tests of a full‐scale CFT/BRB frame—Part I: Specimen design, experiment and analysis
Authors: Tsai Keh‐Chyuan , Hsiao Po‐Chien , Wang Kung‐Juin , Weng Yuan‐Tao , Lin Min‐Lang , Lin Ker‐Chun , Chen Chui‐Hsin , Lai Jiun‐Wei , Lin Sheng‐Lin
Published: April 2008

A series of pseudo‐dynamic tests (PDTs) of a full‐scale 3‐story 3‐bay buckling‐restrained braced frame (BRBF) using concrete‐filled tube columns was tested in the Taiwan National Center for Research on Earthquake Engineering using networked PDT techniques in October 2003. During the tests, real‐time experimental responses and video were webcasted to Internet viewers. The input ground motions adopted for the PDTs were chosen from the 1999 Chi‐Chi and the 1989 Loma Prieta earthquakes and scaled to represent three seismic hazard levels. This paper is in two parts, focusing on the investigations of the overall structure and the local members. This paper constitutes Part I and discusses the design, analytical investigations, and key experimental results of the specimen frame, such as the buckling of the brace‐to‐gusset joints. Part II of the paper, the companion paper, describes the gusset stiffening schemes and detailed experimental behavior of the BRBs and their connections. Experimental peak inter‐story drifts of 0.019 and 0.023 radians, prescribed for the design basis and the maximum credible earthquakes, respectively, are within the target design limits of 0.020 and 0.025 radians. These tests confirmed that the PISA3D and OpenSees nonlinear structural analysis computer programs can simulate the experimental peak shears and floor displacements well. Copyright © 2008 John Wiley & Sons, Ltd.
An entorhinal cortex sulcal pattern is associated with Alzheimer's disease
Authors: Zhan Jiong , Brys Miroslaw , Glodzik Lidia , Tsui Wai , Javier Elizabeth , Wegiel Jerzy , Kuchna Izabela , Pirraglia Elizabeth , Li Yi , Mosconi Lisa , Saint Louis Leslie A. , Switalski Remigiusz , De Santi Susan , Kim Byeong C. , Wisniewski Thomas , Reisberg Barry , Bobinski Matthew , de Leon Mony J.
Published: April 2008

Objectives:

Magnetic resonance (MRI) studies rely on sulcal boundaries to delineate the human entorhinal cortex (EC) and typically show that EC size is reduced in Alzheimer's disease (AD) and a predictor of future dementia. However, it is unknown if variations in the EC sulcal patterns are associated with AD. We classified the lateral EC sulcal boundary as either a rhinal or collateral pattern and tested the hypotheses that the rhinal pattern was (1) more common in AD and (2) associated with a smaller EC size.

Experimental Design:

MRI was used to determine the prevalence of the rhinal and collateral EC patterns in 421 subjects (212 AD, 107 old normal (ONL), and 102 young NL (YNL). Anatomical validation studies of normal subjects were conducted at postmortem in 34 brain hemispheres and in vivo with 21 MRI volume studies. EC pattern reliability was studied with MRI in both cross‐sectional and longitudinal designs.

Principal Observations:

The rhinal pattern was more frequent in the right hemisphere in AD (47%) compared with ONL (28%, odds ratio = 2.25, P = 0.001). EC pattern was not related to ApoE genotype. The validations showed that the EC sulcal pattern was not associated with the neuronal number, surface area, or volume of the EC. In patients with antemortem MRI studied at postmortem it was equivalently determined, that EC patterns are reliably determined on MRI and do not change with the progressive atrophy of AD.

Conclusions:

The data indicate that the right hemisphere rhinal pattern is over represented in AD as compared with control. However, in normal subjects the EC rhinal pattern is not associated with a diminished EC tissue size. It remains to be demonstrated if the right EC rhinal sulcus pattern association with AD reflects genetic or developmental influences. Hum Brain Mapp, 2009. © 2008 Wiley‐Liss, Inc.
Assimilation and accommodation patterns in ventral occipitotemporal cortex in learning a second writing system
Authors: Nelson Jessica R. , Liu Ying , Fiez Julie , Perfetti Charles A.
Published: April 2008

Using fMRI, we compared the patterns of fusiform activity produced by viewing English and Chinese for readers who were either English speakers learning Chinese or Chinese‐English bilinguals. The pattern of fusiform activity depended on both the writing system and the reader's native language. Native Chinese speakers fluent in English recruited bilateral fusiform areas when viewing both Chinese and English. English speakers learning Chinese, however, used heavily left‐lateralized fusiform regions when viewing English, but recruited an additional right fusiform region for viewing Chinese. Thus, English learners of Chinese show an accommodation pattern, in which the reading network accommodates the new writing system by adding neural resources that support its specific graphic requirements. Chinese speakers show an assimilation pattern, in which the reading network established for L1 includes procedures sufficient for the graphic demands of L2 without major change. Hum Brain Mapp, 2009. © 2008 Wiley‐Liss, Inc.
Role of phospholipase A2 and tyrosine kinase in Clostridium difficile toxin A‐induced disruption of epithelial integrity, histologic inflammatory damage and intestinal secretion
Authors: Lima Aldo A. M. , Nascimento Nilberto R. F. , Fang Guodong D. , Yotseff Peter , Toyama M. H. , Guerrant Richard L. , Fonteles Manassés C.
Published: April 2008

Clostridium difficile‐associated disease causes diarrhea to fulminant colitis and death. We investigated the role of phospholipase A2 (PLA2) inhibitors, aristolochic acid (AA), bromophenacyl bromide (BPB) and quinacrine (QUIN) on the C. difficile toxin A‐induced disruption of epithelial integrity, histologic inflammatory damage and intestinal secretion. Toxin A caused severe hemorrhagic and inflammatory fluid secretion at 6–8 h in rabbit ileal segments, an effect that was significantly inhibited by QUIN (71%, P < 0.01), AA (87%, P < 0.000l) or by BPB (51%, P < 0.01). The secretory effect of toxin A was also inhibited in segments adjacent to those with AA (89%, P < 0.01). Furthermore, QUIN or AA substantially reduced the histologic damage seen after 6–8 h in rabbit ileal segments. The cyclooxygenase inhibitor, indomethacin, also significantly inhibited (96%; n = 6) the secretory effects of toxin A in ligated rabbit intestinal segments. The destruction by toxin A of F‐actin at the tight junctions of T‐84 cell monolayers was not inhibited by AA or BPB. AA or QUIN had no effect on the T‐84 cell tissue resistance reduction over 8–24 h after toxin A exposure. All the inhibitors were shown to be effective in the doses administered direct in ileal loops to inhibit PLA2 activity. The data suggest that PLA2 is involved in the major pathway of toxin A‐induced histologic inflammatory damage and hemorrhagic fluid secretion. Copyright © 2008 John Wiley & Sons, Ltd.
Can you keep a secret? Confidentiality in psychotherapy
Authors: Younggren Jeffrey N. , Harris Eric A.
Published: April 2008

Confidentiality is the secret‐keeping duty that arises from the establishment of the professional relationship psychologists develop with their clients. It is a duty created by the professional relationship, it is set forth in the American Psychological Association's (2002) Ethical Principles and Code of Conduct, and it is codified in many state regulations. However, the difference between confidentiality and legal privilege; how, why, and when it can be violated; and the reasons for so doing are not well understood by many practitioners. While on the surface confidentiality might seem to be an easy concept to apply to professional practice, in fact it is quite complex and filled with exceptions that frequently differ from circumstance to circumstance and from state to state. A lack of respect for and a lack of familiarity with the significance of these exceptions could have dire professional consequences. This article reviews the ethical imperative of confidentiality and then provides examples of legal cases that help to better understand its complexity. Then, we offer strategies designed to help metal health practitioners when they are confronted with questions regarding confidentiality and privilege. © 2008 Wiley Periodicals, Inc. J Clin Psychol: In Session 64: 1–12, 2008.
International agricultural research as a global public good: concepts, the CGIAR experience and policy issues
Authors: Dalrymple Dana G.
Published: April 2008

Global Public Goods (GPGs) are becoming increasingly important in international development, but little attention has been given to their role in science and technology. Yet one clear example—also overlooked in most of the GPG literature—has existed for 35 years: the Consultative Group on International Agricultural Research (CGIAR). Agricultural research in the poorer developing nations is largely conducted in the public sector and the CGIAR was formed to develop, with these nations, improved technologies and policies for their use in food production—international research spillovers. The process has worked well: the CGIAR has, perhaps unwittingly, been a leading provider of GPGs. But public funding for the CGIAR from international development agencies has become tighter and more restricted, threatening to weaken its global scientific capacity. Additional and more research‐oriented funding sources are needed. Greater understanding of the GPG concept as it applies to research, both public and private, is needed at the policy level if these efforts are to be realised and endure. Published in 2008 by John Wiley & Sons, Ltd.
Field notes on administering shock modules
Authors: De Weerdt Joachim
Published: April 2008

Increasingly panel household questionnaires in developing countries will include a shock module to collect information on past shocks experienced by the household. Still, very little information is available on what one needs to take into consideration when designing these modules. This note discusses field experiences gained from piloting a shock module in the Kagera Region of Tanzania. Pilots were conducted with two fundamentally different designs of shock modules. We discuss the advantages and disadvantages of using a structural form shock module, which walks the respondent through a list of shocks, and compare it to using a reduced form one, which probes for welfare changes over time. Copyright © 2008 John Wiley & Sons, Ltd.
A cytoprotective role for the heme oxygenase‐1/CO pathway during neural differentiation of human mesenchymal stem cells
Authors: Barbagallo Ignazio , Tibullo Daniele , Di Rosa Michelino , Giallongo Cesarina , Palumbo Giuseppe A. , Raciti Giuseppina , Campisi Agata , Vanella Angelo , Green Colin J. , Motterlini Roberto
Published: April 2008

The inducible protein heme oxygenase‐1 (HO‐1) catalyzes the oxidation of heme to carbon monoxide (CO) and biliverdin, which play a concerted action in cytoprotection against oxidative stress and in the modulation of cell proliferation and differentiation. Here we report that both HO‐1 expression and activity can be highly increased in undifferentiated human mesenchymal stem cells (MSCs) treated with hemin, a known HO‐1 inducer. However, HO‐1 mRNA and protein expression gradually decrease when MSCs undergo neural differentiation in vitro, making them extremely susceptible to glutamate‐mediated cytotoxicity. A time course for HO‐1 revealed that this protein is markedly down‐regulated after 2 days and returns to control levels 6 days after differentiation. Treatment with glutamate (250 μM) after 2 days of neural differentiation resulted in a more pronounced lactate dehydrogenase release, a marker of cell injury, compared with undifferentiated cells. Notably, cells pretreated with hemin (50 μM) or compounds that release small amounts of CO (10 μM CORM‐3 and CORM‐A1) rendered cells more resistant to glutamate‐induced toxicity; this effect was evident in both undifferentiated and differentiated MSCs. Our findings indicate that MSCs become more vulnerable to oxidative injury during the early stages of differentiation via mechanisms that involve a temporary inhibition of HO‐1 expression. Thus, overexpression of HO‐1 and CO‐releasing molecules could provide a possible therapeutic strategy to improve cell viability during neural differentiation in applications that use stem cell technology. © 2008 Wiley‐Liss, Inc.
Distribution of mitochondria along small‐diameter myelinated central nervous system axons
Authors: Edgar Julia M. , McCulloch Mailis C. , Thomson Christine E. , Griffiths Ian R.
Published: April 2008

Small‐diameter myelinated CNS axons are preferentially affected in multiple sclerosis (MS) and in the hereditary spastic paraplegias (HSP), in which the distal axon degenerates. Mitochondrial dysfunction has been implicated in the pathogenesis of these and other disorders involving axonal degeneration. The aim of this study was to determine whether the frequency of axonal mitochondria changes along the length of small‐diameter fibers and whether there is a preferential localization to the region of the node of Ranvier. We find that mitochondrial numbers do not change along the length of a myelinated small‐diameter fiber, and, in contrast to the peripheral nervous system, there is no tendency for mitochondrial numbers to increase at the node. © 2008 Wiley‐Liss, Inc.
Selective death of newborn neurons in hippocampal dentate gyrus following moderate experimental traumatic brain injury
Authors: Gao Xiang , Deng‐Bryant Ying , Cho Wongil , Carrico Kimberly M. , Hall Edward D. , Chen Jinhui
Published: April 2008

Memory impairment is one of the most significant residual deficits following traumatic brain injury (TBI) and is among the most frequent complaints heard from patients and their relatives. It has been reported that the hippocampus is particularly vulnerable to TBI, which results in hippocampus‐dependent cognitive impairment. There are different regions in the hippocampus, and each region is composed of different cell types, which might respond differently to TBI. However, regional and cell type‐specific neuronal death following TBI is not well described. Here, we examined the distribution of degenerating neurons in the hippocampus of the mouse brain following controlled cortical impact (CCI) and found that the majority of degenerating neurons observed were in the dentate gyrus after moderate (0.5 mm cortical deformation) CCI‐TBI. In contrast, there were only a few degenerating neurons observed in the hilus, and we did not observe any degenerating neurons in the CA3 or CA1 regions. Among those degenerating cells in the dentate gyrus, about 80% of them were found in the inner granular neuron layer. Analysis with cell type‐specific markers showed that most of the degenerating neurons in the inner granular neuron layer are newborn immature neurons. Further quantitative analysis shows that the number of newborn immature neurons in the dentate gyrus is dramatically decreased in the ipsilateral hemisphere compared with the contralateral side. Collectively, our data demonstrate the selective death of newborn immature neurons in the hippocampal dentate gyrus following moderate injury with CCI in mice. This selective vulnerability of newborn immature dentate neurons may contribute to the persistent impairment of learning and memory post‐TBI and provide an innovative target for neuroprotective treatment strategies. © 2008 Wiley‐Liss, Inc.
Identification of the Fugloyarbanki tephra in the NGRIP ice core: a key tie‐point for marine and ice‐core sequences during the last glacial period
Authors: Davies S. M. , Wastegård S. , Rasmussen T. L. , Svensson A. , Johnsen S. J. , Steffensen J. P. , Andersen K. K.
Published: April 2008

A visible tephra horizon in the NGRIP ice core has been identified by geochemical analysis as the Fugloyarbanki Tephra, a widespread marker horizon in marine cores from the Faroe Islands area and the northern North Atlantic. An age of 26 740 ± 390 yr b2k (1σ uncertainty) is derived for this tephra according to the new Greenland Ice Core Chronology (GICC05) based on multi‐parameter counting of annual layers. Detection of this tephra for the first time within the NGRIP ice core provides a key tie‐point between marine and ice‐core records during the transition between MIS 3 and 2. Identification of this volcanic event within the Greenland records demonstrates the future potential of using tephrochronology to precisely correlate palaeoarchives in widely separated localities that span the last glacial period, as well as providing a potential method for examining the extent of the radiocarbon marine reservoir effect at this time. Copyright © 2008 John Wiley & Sons, Ltd.
Effect of column temperature on enantioseparation of dihydropyrimidinones using alcohol solvated Chiralpak AS and AS‐H columns
Authors: Wang Fang , Han Jun , Yeung David , Semin David , Cheetham Janet
Published: April 2008

In this study we report the application of column temperature programs to compare the chromatographic behaviors of four commercially available dihydropyrimidinone (DHP) compounds on Chiralpak AS and AS‐H phases under different alcohol solvation conditions such as 1‐propanol (1‐PrOH), 2‐methyl‐1‐PrOH (2‐Me‐1‐PrOH), 1‐butanol (1‐BuOH), 2‐BuOH, and tert‐BuOH (t‐BuOH) in n‐hexane (n‐Hex). It was observed that the apparent retention factors of the DHP compounds on the AS phase in t‐BuOH/n‐Hex mobile phase had the largest reduction (>27%) among the mobile phases studied after a heating and cooling temperature cycle (10 to 50 back to 10°C). However, the average reduction of the apparent retention factors of the compounds on t‐BuOH solvated AS‐H was less than 4%. No clear trend of changes in the apparent retention factors on AS and AS‐H columns was observed in other alcohol modified mobile phases. Step‐temperature programs showed that alcohol solvated AS phase had larger changes in the apparent retention factors with time than those of AS‐H phase at the elevated temperature step (50°C). Both t‐BuOH solvated AS and AS‐H phases showed kinetic behaviors in chromatographic processes at the elevated temperature.
Preparation and HPLC evaluation of a new 1,3‐alternate 25,27‐bis‐[p‐chlorobenzyloxy]‐26,28‐bis‐[3‐propyloxy]‐calix[4]arene silica bonded stationary phase
Authors: Sliwka‐Kaszynska Magdalena , Karaszewski Sebastian
Published: April 2008

The 1,3‐alternate 25,27‐bis‐[p‐chlorobenzyloxy]‐26,28‐bis‐[3‐propyloxy]‐calix[4]arene‐bonded silica gel stationary phase was synthesized, structurally characterized, and used as a selector in high performance liquid chromatography. Selectivity studies on that phase used aromatic positional isomers, alkylbenzenes, polynuclear aromatic hydrocarbons, sulfonamides, and non‐steroidal anti‐inflammatory drugs as analytes. The effects of organic modifier content and pH of the mobile phase on retention and selectivity of selected aromatic positional isomers were studied. Selectivity comparisons of the novel phase vs. 1,3‐alternate 25,27‐di‐[benzyloxy]‐26,28‐bis‐[3‐propyloxy]‐calix[4]arene phase and commercially available RP‐Phenyl phases were performed. The retention mechanism was also discussed. The results indicated that the calixarene stationary phase behaves like a reversed‐phase packing; however, other retention mechanisms seem to be involved in the separation process.
Proteome analysis of non‐model plants: A challenging but powerful approach
Authors: Carpentier Sebastien Christian , Panis Bart , Vertommen Annelies , Swennen Rony , Sergeant Kjell , Renaut Jenny , Laukens Kris , Witters Erwin , Samyn Bart , Devreese Bart
Published: April 2008

Biological research has focused in the past on model organisms and most of the functional genomics studies in the field of plant sciences are still performed on model species or species that are characterized to a great extent. However, numerous non‐model plants are essential as food, feed, or energy resource. Some features and processes are unique to these plant species or families and cannot be approached via a model plant. The power of all proteomic and transcriptomic methods, that is, high‐throughput identification of candidate gene products, tends to be lost in non‐model species due to the lack of genomic information or due to the sequence divergence to a related model organism. Nevertheless, a proteomics approach has a great potential to study non‐model species. This work reviews non‐model plants from a proteomic angle and provides an outline of the problems encountered when initiating the proteome analysis of a non‐model organism. The review tackles problems associated with (i) sample preparation, (ii) the analysis and interpretation of a complex data set, (iii) the protein identification via MS, and (iv) data management and integration. We will illustrate the power of 2DE for non‐model plants in combination with multivariate data analysis and MS/MS identification and will evaluate possible alternatives. © 2008 Wiley Periodicals, Inc., Mass Spec Rev 27: 354–377, 2008
NMR and Texture Analyses in Relation to Swelling Kinetics of 2‐Hydroxyethyl Methacrylate/N‐Vinylpyrrolidinone Hydrogels
Authors: Ng Loo‐Teck , Swami Salesh
Published: April 2008

This study investigates the relationship between swelling kinetics and the relative stress relaxation (SR) values from texture analysis, as well as the relaxation times from proton NMR analysis of photopolymerized 2‐hydroxyethyl methacrylate (HEMA)/N‐vinyl pyrrolidinone (NVP) hydrogels with varying HEMA and NVP contents. Swelling tests in Milli‐Q water at 37 °C showed that hydrogels of higher NVP content displayed non‐Fickian diffusion kinetics. Texture analysis indicated the existence of a trend between SR values and diffusion kinetics with the hydrogels that displayed non‐Fickian diffusion having significantly lower SR values. Proton NMR analysis showed that the hydrogel with higher NVP content (non‐Fickian diffusion kinetics) displayed substantially longer relaxation times, which indicated slower exchange of water molecules between different sites within the meshes of the polymer matrix, attributable probably to hydrogen bonding and hydrophilic attraction between polymer and the water molecules. A relationship appeared to exist for the hydrogels understudy with hydrogels exhibiting non‐Fickian diffusion kinetics displaying lower SR values and longer relaxation times.
Effect of Non‐Woven Carbon Nanofiber Mat Presence on Cure Kinetics of Epoxy Nanocomposites
Authors: Aussawasathien Darunee , Sancaktar Erol
Published: April 2008

Summary: An investigation was carried out into the cure kinetics of carbon nanofiber (CNF) mat‐epoxy nanocomposites, composed of bisphenol‐A based epoxy resin and diethylene triamine as a curing agent. It was observed that the rate of cure reaction for CNF mat‐epoxy nanocomposites was higher than that for neat epoxy resin at low curing temperatures and the presence of the CNF mat produced the maximum influence at a certain curing temperature and time. At high curing temperature and long curing times, the effect of CNF mat on the cure rate was insignificant. The CNF mat‐epoxy composite exhibited somewhat lower value of activation energy than that of the neat epoxy system at the beginning of the curing stage. The weight fraction of CNF mat also affected the cure reaction of epoxy nanocomposites at the same curing temperature. As the amount of CNF mat increased, the cure rate was higher at the same cure time. However, at high CNF mat loading, the cure reaction was retarded since the amount of epoxy and hardener decreased dramatically at high CNF contents together with the hindering effect of the CNF mat on the diffusion of epoxy resin and the curing agent, leading to lower crosslinking efficiency. Although the curing efficiency of epoxy nanocomposites dropped at high CNF mat content, the glass transition temperature (Tg) was still high due to the ultra‐high strength of the CNF mat. The cure kinetics of CNF mat‐epoxy nanocomposites was in good agreement with Kamal's model.
Effect of Zinc Oxide on Morphology and Mechanical Properties of Polyoxymethylene/Zinc Oxide Composites
Authors: Wacharawichanant Sirirat
Published: April 2008

This paper studies the effects of zinc oxide (ZnO) on morphology and mechanical properties of pure polyoxymethylene (POM) and POM/ZnO composites. POM/ZnO composites with varying concentration of ZnO were prepared by melt mixing technique in a twin screw extruder. The dispersion of ZnO particles on POM composites was studied by scanning electron microscope (SEM). It is observed that the dispersion of ZnO particles is relatively good. The mechanical properties of the composites such as tensile strength, stress at break, Young's modulus and impact strength were measured. Increasing content of ZnO up to 4.0 wt% increases the impact strength of POM. Addition of ZnO beyond 4.0 wt% decreases the impact strength. The composites containing ZnO content greater than 2.0 wt% show increased Young's Modulus. The tensile strength and stress at break decrease with increasing ZnO content. This may be due to the compatibility between ZnO and POM.
Effect of Heat Treatment Temperature on Surface Topography and Hydrophobicity of Polydimethylsiloxane/Titanium Oxide Hybrid Films
Authors: Jindasuwan Sunisa , Sujaridworakun Pornapa , Jinawath Supatra , Supothina Sitthisuntorn
Published: April 2008

Hydrophobic thin films of polydimethylsiloxane (PDMS) ‐ titamium (hydrous) oxide hybrid material were deposited on glass substrate by dip coating from the precursor containing hydroxyl‐terminated PDMS and titanium tetraisopropoxide (TIP), as well as small amounts of water and ethyl acetoacetate. Film's hydrophobicity was evaluated by performing contact angle measurement, while surface topography was analyzed by using an atomic force microscope (AFM). Effects of heat treatment temperature and TIP:PDMS ratio on film's hydrophobicity are described.
Molecular Functionalization of Cold‐Plasma‐Treated Bombyx mori Silk
Authors: Nimmanpipug Piyarat , Lee Vannajan Sanghiran , Janhom Sorapong , Suanput Pradoong , Boonyawan Dherawan , Tashiro Kohji
Published: April 2008

Bombyx mori silk treated by cold SF6 plasma was found to show higher hydrophobic property than the original silk. In order to clarify the chemical changes occurring in this treatment, the changes of functional groups of silk surface were investigated by attenuated total reflection (ATR) infrared spectroscopy, surface charge determination, and quantum mechanical calculation. Infrared spectra of original and plasma‐treated silks do not show any change in the frequency regions of amide I, II, and III bands which locate at around 1627, 1513, and 1228 cm−1, respectively. Slight changes were detected for the peak intensities of the bands locating in the frequency region of 1000–1050 cm−1 after plasma treatment. This suggests the formation of CF groups in the Bombyx mori silk chain. The zeta potential experiment suggested that the electrostatic charges of the silk surface were not affected by the plasma treatment. In order to investigate the surface state of the plasma treated silk, the density functional calculation was performed for the model compounds with similar chemical structure as that of Bombyx mori silk. In this calculation, a fluorine radical was located at the various positions of the model compound, and the energetically most plausible structures were extracted to show the chemical reaction of CH + F− → CF + H−.