bluuebunny/crossref_metadata_2025 huggingface dataset:
Kinetics of diffusion in polyacrylonitrile fiber formation
Authors: Hou Chen , Qu Rong‐jun , Liang Ying , Wang Cheng‐guo
Published: March 2005

A H2O/dimethyl sulfoxide (DMSO) mixture was used as the coagulation bath of the wet‐spun process for polyacrylonitrile fibers. Diffusion behaviors of coagulate and solvent of the protofibers were studied. Diffusion coefficients of H2O and DMSO of the protofibers, prepared by acrylonitrile (AN) homopolymers, were also determined. It was found that diffusion coefficients of H2O and DMSO in the protofibers prepared by AN homopolymers, synthesized by DMSO solution polymerization, are highest compared with those of AN homopolymers synthesized by H2O/DMSO mixture suspension polymerization and aqueous suspension polymerization. With increasing polyacrylonitrile concentration in the dope, diffusion coefficients of H2O and DMSO decreased continuously. Diffusion coefficients of H2O and DMSO increased concomitantly with increasing bath temperature, but the changes of diffusion coefficient values were less prominent when the temperature increased beyond 60°C. When DMSO concentration in the coagulation bath was 55 wt %, the values of diffusion coefficients of H2O and DMSO were minimal. Diffusion coefficients increased with increasing jet stretch minus ratio. When the protofiber radius was increased, there was a corresponding increase of diffusion coefficients of H2O and DMSO. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1529–1533, 2005
Synthesis and characterization of aniline and o‐toluidine conducting copolymer microtubes with the template‐synthesis method
Authors: Xin Ling‐Yun , Zhang Xiao‐Gang , Zhang Guo‐Qing , Shen Cheng‐Min
Published: March 2005

Copolymer microtubes composed of aniline and o‐toluidine were prepared through the synthesis of the desired polymer within the pores of a microporous anodic aluminum oxide (AAO) template. Scanning electron microscopy and transmission electron microscopy revealed that the obtained copolymer microtubes had uniform and well‐aligned arrays, and the aspect ratios of the AAO membranes could be controlled through their diameter and length. Infrared spectrometry and X‐ray photoelectron spectroscopy supported the surface analysis for the microtubes and also proved the formation of copolymers. Ultraviolet–visible/near‐infrared spectra proved that the doping effect decreased with an increase of o‐toluidine in the copolymers, but the solubility greatly improved (up to 3.83 g/L in N,N‐dimethylformamide), and the conductivity was as high as approximately 17.4 S cm−1. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1539–1543, 2005
Inferential estimation of molecular weights of polybutadiene rubber by neural networks
Authors: Padmavathi G. , Mandan M. G. , Mitra S. P. , Chaudhuri K. K. , Patel Shital J. , Dabke S. P.
Published: March 2005

Molecular weight distribution, which is characterized by its averages like number average (Mn) and weight average (Mw), is one of the important properties of polybutadiene rubber (PBR), and it is difficult to measure. The objective of this work is to develop models to predict Mn and Mw from readily available process variables. Neural networks that are capable of mapping highly complex and non‐linear dependencies have been adapted to develop models for the Mn and Mw of PBR. The molecular weight distribution and its averages of PBR samples collected over a wide range of operating conditions were measured by the conventional Gel Permeable Chromatograph (GPC) method. Neural networks were trained with relevant data to predict Mn and Mw from process variables. The trained networks were found to generalize well when tested with new data. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1611–1618, 2005
Swelling behavior of poly(acrylamide‐co‐N‐vinylimidazole) hydrogels under different environment conditions
Authors: Işık Belma , Doǧantekin Banu
Published: March 2005

A series of random copolymers of acrylamide and N‐vinylimidazole, poly(AAm‐co‐NVI), with various compositions were prepared using redox copolymerization. The influence of environmental conditions such as pH, temperature, and ionic strength on the swelling behavior of the copolymeric hydrogels was investigated. The hydrogels exhibited the highest equilibrium swelling in basic medium at high temperature. Equilibrium swelling decreased with rising ionic strength at pH 5.0. As pH increased, equilibrium swelling of the hydrogels increased at pH 11.0 and I = 0.20 M. Swelling kinetics of the hydrogels was found to be non‐Fickian at 25°C. The process tended to be Fickian at higher pH and temperature. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1783–1788, 2005
Determination of gelation temperature of poly(vinyl chloride) by thermomechanical and thermogravimetric parameters
Authors: Boztuǧ Ali , Zengin H. Bayram , Basan Satılmış
Published: March 2005

Preheating between the temperatures of 200 and 280°C is done to a film‐structured poly(vinyl chloride) (PVC) sample, which has a gelation temperature ∼ 250°C. After this preheat, the PVC's thermomechanical and thermal differences, at temperatures before and after thermal gelation, are observed. Consequently, when some thermomechanical and thermal parameters, obtained at temperatures before and after gelation, are compared, it can be said that this is an easier method to determine the gelation temperature of a polymer. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1635–1640, 2005
Reaction kinetics and characteristics of polyurethane/clay nanocomposites
Authors: Kim Dae Su , Kim Jin‐Tae , Woo Won Bum
Published: March 2005

The reaction behavior and physical properties of polyurethane (PU)/clay nanocomposite systems were investigated. Organically modified clay was used as nanofillers to formulate the nanocomposites. Differential scanning calorimetry was used to study the reaction behavior of the PU/clay nanocomposite systems. The reaction rate of the nanocomposite systems increased with increasing clay content. The reaction kinetic parameters of proposed kinetic equations were determined by numerical methods. The glass transition temperatures of the PU/clay nanocomposite systems increased with increasing clay content. The thermal decomposition behavior of the PU/clay nanocomposites was measured by using thermogravimetric analysis. X‐ray diffractometer and transmission electronic microscope data showed the intercalation of PU resin between the silicate layers of the clay in the PU/clay nanocomposites. A universal testing machine was used to investigate the tensile properties of the PU/clay nanocomposites. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1641–1647, 2005
Adhesion property of novel polyimides with 1‐[3′,5′‐bis(trifluoromethyl)phenyl] pyromellitic dianhydride
Authors: Myung B. Y. , Ahn C. J. , Yoon T. H.
Published: March 2005

Novel polyimides were synthesized from 1‐[3′,5′‐bis(trifluoromethyl)phenyl] pyromellitic dianhydride (6FPPMDA) by a conventional two‐step process: the preparation of poly(amic acid) followed by solution imidization via refluxing in p‐chlorophenol. The diamines used for polyimide synthesis included bis(3‐aminophenyl)‐3,5‐bis(trifluoromethyl)phenyl phosphine oxide, bis(3‐aminophenyl)‐4‐trifluoromethylphenyl phosphine oxide, and bis(3‐aminophenyl)phenyl phosphine oxide. The synthesized polyimides were designed to have a molecular weight of 20,000 g/mol by off‐stoichiometry and were characterized by Fourier transform infrared, NMR, differential scanning calorimetry, and thermogravimetric analysis. In addition, their intrinsic viscosity, solubility, water absorption, and coefficient of thermal expansion (CTE) were also measured. The adhesion properties of the polyimides were evaluated via a T‐peel test with bare and silane/Cr‐coated Cu foils, and the failure surfaces were investigated with scanning electron microscopy. The 6FPPMDA‐based polyimides exhibited high glass‐transition temperatures (280–299°C), good thermal stability (>530°C in air), low water absorption (1.46–2.16 wt %), and fairly low CTEs (32–40 ppm/°C), in addition to good adhesion properties (83–88 g/mm) with silane/Cr‐coated Cu foils. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1801–1809, 2005
Influence of KOH solution on the tensile strength and chemical stability of carbon fiber‐reinforced epoxy resin composites
Authors: Wazzan A. A. , Al‐Turaif H. A. , Daous M. A.
Published: March 2005

The effect of a relatively high concentration of KOH solution (4M) on the mechanical properties and chemical stability of carbon fiber‐reinforced epoxy resin composites, prepared with different volume fractions of reinforcement, were investigated. Upon treatment of specimens of such composites with the KOH solution at different temperature and for different durations, their tensile strengths were adversely affected to varying degrees, depending on treatment conditions and volume percent of carbon fiber reinforcement used. Surfaces of treated specimens were examined for matrix stability, fiber disruption, and debonding. Optical microscopy, scanning electron microscopy (SEM), and X‐ray photoelectron spectroscopy (XPS) were used to evaluate chemical and mechanical degradation of these composites. Results clearly showed that prolonged exposure of composite specimens to such aggressive environments markedly increased the degradation of their mechanical properties. On the other hand, these results also showed that increasing the volume fraction of the carbon fiber reinforcement reduced the severity of degradation of these composite and enhanced their mechanical stability. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1682–1690, 2005
Degradation of low‐density polyethylene during extrusion. VI. Effects of oxygen content in air gap
Authors: Andersson Thorbjörn , Wesslén Bengt
Published: March 2005

In our previous papers polyethylene degradation during extrusion coating has been studied and the type of degradation products that are formed and from which step they originate have been discussed. A trained sensory panel has rated the off‐flavor intensities in water samples that have been in contact with various extruded films. Encouraged by the results from these investigations and the documented synergism between aldehydes and ketones and aldehydes and carboxylic acids in off‐flavor intensity, the present study was aimed at confirming the belief that the off‐flavor depends on the presence of oxidative degradation products that have migrated from the film into the water. By decreasing the oxygen concentration in the atmosphere surrounding the extruded melt presence of the highly oxidized species (i.e., carbonyl compounds and carboxylic acids) would decrease and thus the off‐flavor in the water should decline. From this study it could be concluded that the extrusion temperature and the oxygen content in the atmosphere nearest the molten film before quenching are the most important parameters for oxidative degradation and residence time in the air gap influence the amount of oxidative degradation products formed. Furthermore we concluded that the off‐flavor intensity is strongly correlated to the surface oxidation index of the film. Carboxylic acids are present in the water extracts of extruded films and are related to the off‐flavor intensities. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1767–1775, 2005
The needs of terminally ill cancer patients versus those of caregivers for information regarding prognosis and end‐of‐life issues
Authors: Clayton Josephine M. , Butow Phyllis N. , Tattersall Martin H. N.
Published: March 2005

BACKGROUND

The difficulty of negotiating the concerns of family members while also respecting the needs of the patient adds complexity to the task of discussing prognosis and end‐of‐life (EOL) issues with terminally ill cancer patients. The informational needs of caregivers may be different from those of the patients themselves with regard to these topics. However, to the authors' knowledge, this issue has received relatively little research attention.

METHODS

The authors conducted focus groups and individual interviews with 19 patients with far advanced cancer and 24 caregivers from 3 palliative care (PC) services in Sydney and 22 PC health professionals (HPs) from around Australia. The focus groups and individual interviews were audiotaped and fully transcribed. Additional focus groups or individual interviews were conducted until no additional topics were raised. The participants' narratives were analyzed using qualitative methodology.

RESULTS

The participants had varying views regarding whether patients and caregivers should be told different information concerning prognosis and EOL issues. Three themes were identified from the transcripts regarding meeting the informational needs of both the patients and caregivers: 1) the importance of consistency and openness, 2) the specific information needed to care for the patient, and 3) the value of having separate discussions with the patient and caregiver. A desire to restrict the patient's access to information by the caregiver or vice versa was reported by the HPs to be one of the most challenging issues when discussing prognosis and EOL issues. Three themes were identified with regard to this issue: 1) autonomy versus protection, 2) negotiating family dynamics, and 3) difficulty using interpreters.

CONCLUSIONS

The results of the current study emphasized the importance of considering the distinct informational needs of caregivers, as well as those of the patient, when discussing prognosis and EOL issues. Cancer 2005. © 2005 American Cancer Society.
Connexin36 mediates gap junctional coupling of alpha‐ganglion cells in mouse retina
Authors: Schubert Timm , Degen Joachim , Willecke Klaus , Hormuzdi Sheriar G. , Monyer Hannah , Weiler Reto
Published: March 2005

Alpha‐ganglion cells are present in all vertebrate retinae and are subdivided into ON and OFF types according to their level of dendritic ramification within the inner plexiform layer. They have large dendritic fields and usually a good responsiveness to moving stimuli. They were the first ganglion cells in which tracer coupling was observed, suggesting the presence of gap junctions composed of unknown connexins. Here we show that ON‐alpha‐ganglion cells in the mouse retina are coupled to amacrine cells, whereas OFF‐alpha‐ganglion cells are coupled to other OFF‐alpha‐ganglion cells and to amacrine cells. These tracer coupling patterns were completely absent in mice deficient in connexin36 (Cx36). The expression of Cx36 protein in alpha‐ganglion cells but not in coupled amacrine cells was confirmed in mice in which the Cx36 coding DNA was replaced by the lacZ reporter gene. The dendritic localization and the distribution pattern of Cx36 patches, analyzed in mice in which the enhanced green fluorescent protein (EGFP) was linked to the C‐terminal region of the Cx36 protein, revealed a rather small number of fluorescent plaques and different patterns for ON‐ and OFF‐alpha‐ganglion cells. Furthermore, tracer coupling between OFF‐alpha‐ganglion cells could be inhibited by quinine, a gap junctional blocker with a slight preference for gap junctions formed by Cx36. These data strongly suggest that Cx36 gap junction channels are functional not only in interneurons but also in output neurons of the retina and are responsible for distinct coupling patterns of ganglion cells. J. Comp. Neurol. 485:191–201, 2005. © 2005 Wiley‐Liss, Inc.
Prior elevation of IL‐18 promotes rapid early IFN‐γ production during staphylococcal infection
Authors: Culshaw Shauna , Leung Bernard P. , Gracie J. Alastair , Campbell Carol C. , Thomson Duncan , Gemmell Curtis , Liew Foo Y. , McInnes Iain B.
Published: March 2005

Systemic Staphylococcus aureus infection is associated with significant morbidity and mortality arising from both bacterial and host immune factors. IL‐18 is a pro‐inflammatory cytokine of the IL‐1 superfamily that exhibits broad functional effects in innate and acquired immune responses and which has been found in high levels in several chronic inflammatory and autoimmune diseases. Over‐expression of IL‐18 may promote early resolution of infection or could promote a detrimental exaggerated immune response. This was explored in a model of S. aureus infection. We report increased mortality in Swiss mice that were given recombinant IL‐18 prior to inoculation with S. aureus LS‐1. IL‐18 administration prior to infection induced preferentially enhanced IFN‐γ mRNA expression in peripheral blood leukocytes and spleen, especially splenic NK cells. This correlated with increased IFN‐γ protein detection in serum, and leukocyte and spleen cultures at subsequent discrete time points. These data suggest that increased mortality following gram‐positive infection in autoimmune diseases could in part reflect the impact of high levels of pleiotropic pro‐inflammatory cytokines such as IL‐18 present prior to the onset of infection.
Extracellular lysosome‐associated membrane protein‐1 (LAMP‐1) mediates autoimmune disease progression in the NOD model of type 1 diabetes
Authors: De Carvalho Bittencourt Marcelo , Herren Suzanne , Graber Pierre , Vilbois Francis , Pasquali Christian , Berney Claude , Plitz Thomas , Nicoletti Ferdinando , Kosco‐Vilbois Marie H.
Published: March 2005

Treatment (from 5 to 25 weeks of age) with a novel blocking monoclonal antibody, mAb I‐10, directed against the plasma membrane (pm) form of LAMP‐1, protected against development of autoimmune diabetes in the NOD mouse. A shorter course of treatment, i.e. from 5 to 12 weeks of age, significantly reduced the occurrence of insulitis as well as disease onset. Interfering with pm‐LAMP‐1 required continuous treatment as tolerance was not observed when treatment was stopped, and no higher proportion of cells with a T regulatory phenotype (e.g. CD4+CD25+) were induced. The mechanism appears to involve modulating a proinflammatory cytokine, as the proportion of pancreatic‐infiltrating IFN‐γ‐positive cells was significantly reduced in the mAb I‐10‐treated group. These results demonstrate an unexpected role for pm‐LAMP‐1 in autoimmune disease progression, and suggest that further investigation should be performed to understand how this molecule modulates IFN‐γ‐driven responses.
Discovery and characterization of highly immunogenic and broadly recognized mimics of the HIV‐1 CTL epitope Gag77–85
Authors: Boggiano César , Moya Rosa , Pinilla Clemencia , Bihl Florian , Brander Christian , Sidney John , Sette Alessandro , Blondelle Sylvie E.
Published: March 2005

Human immunodeficiency virus (HIV)‐specific cytotoxic T lymphocytes (CTL) play an important role in HIV infection. Given the viral genetic diversity, the selection of suitable antigens and epitope variants will be important in the design of an effective vaccine. We have previously shown that combinatorial libraries are useful tools to identify epitope mimics as well as potentially cross‐reactive natural sequences in protein databases. We have applied this approach to the HIV Gag p17‐derived epitope SL9 (SLYNTVATL) to identify broadly recognized SL9 mimics and to assess the cross‐recognition of naturally occurring SL9 variants. Nine nonapeptides were identified that were up to one order of magnitude more effective than SL9 in stimulating CTL responses in PBMC from HIV‐infected subjects. Using transgenic mice, we demonstrate that a number of these epitope mimics were able to generate de novo T cell responses that cross‐reacted with the original SL9 sequence. Particularly, mimics with changes at the relatively conserved F‐pocket anchor residue were frequently cross‐recognized. This approach may lead to vaccine candidates with higher in vivo immunogenicity and increased potential for cross‐recognition of naturally occurring SL9 variants.
Increased inflammation in mice deficient for the chemokine decoy receptor D6
Authors: de la Torre Yeny Martinez , Locati Massimo , Buracchi Chiara , Dupor Jana , Cook Donald N. , Bonecchi Raffaella , Nebuloni Manuela , Rukavina Daniel , Vago Luca , Vecchi Annunciata , Lira Sergio A. , Mantovani Alberto
Published: March 2005

Chemokines are chemotactic cytokines with a key role in the control of cell trafficking and positioning under homeostatic and inflammatory conditions. D6 is a promiscuous 7‐transmembrane‐domain receptor expressed on lymphatic vessels which recognizes most inflammatory, but not homeostatic, CC chemokines. In vitro experiments demonstrated that D6 is unable to signal after ligand engagement, and it is structurally adapted to sustain rapid and efficient ligand internalization and degradation. These unique functional properties lead to the hypothesis that D6 may be involved in the control of inflammation by acting as a decoy and scavenger receptor for inflammatory chemokines. Consistent with this hypothesis, here we report that D6–/– mice showed an anticipated and exacerbated inflammatory response in a model of skin inflammation. Moreover, the absence of D6 resulted in increase cellularity and inflammatory‐chemokine levels in draining lymph nodes. Thus, D6 is a decoy receptor structurally adapted and strategically located to tune tissue inflammation and control transfer of inflammatory chemokines to draining lymph nodes.
A propensity score approach to estimating the cost–effectiveness of medical therapies from observational data
Authors: Mitra Nandita , Indurkhya Alka
Published: March 2005

Health summary measures are commonly used by policy makers to help make decisions on the allocation of societal resources for competing medical treatments. The net monetary benefit is a health summary measure that overcomes the statistical limitations of a popular measure namely, the cost–effectiveness ratio. We introduce a linear model framework to estimate propensity score adjusted net monetary benefit. This method provides less biased estimates in the presence of significant differences in baseline measures and demographic characteristics between treatment groups in quasi‐randomized or observational studies. Simulation studies were conducted to better understand the utility of propensity score adjusted estimates of net monetary benefits when important covariates are unobserved. The results indicated that the propensity score adjusted net monetary benefit provides a robust measure of cost–effectiveness in the presence of hidden bias. The methods are illustrated using data from SEER‐Medicare for the treatment of bladder cancer. Copyright © 2005 John Wiley & Sons, Ltd.
What caused the early millennium slowdown? Evidence based on vector autoregressions
Authors: Peersman Gert
Published: March 2005

This paper uses a simple VAR for the USA and Euro area to analyse the underlying shocks of the early millennium slowdown, i.e. supply, demand, monetary policy and oil price shocks. The results of two identification strategies are compared. One is based on traditional zero restrictions and, as an alternative, an identification scheme based on more recent sign restrictions is proposed. The main conclusion is that the recent slowdown is caused by a combination of several shocks: negative aggregate supply and aggregate spending shocks, the increase of oil prices in 1999, and restrictive monetary policy in 2000. These shocks are more pronounced in the USA than the Euro area. The results are somewhat different depending on the identification strategy. It is illustrated that traditional zero restrictions can have an influence on the estimated impact of certain shocks. Copyright © 2005 John Wiley & Sons, Ltd.
Comparing shocks and frictions in US and euro area business cycles: a Bayesian DSGE Approach
Authors: Smets Frank , Wouters Raf
Published: March 2005

This paper estimates a DSGE model with many types of shocks and frictions for both the US and the euro area economy over a common sample period (1974–2002). The structural estimation methodology allows us to investigate whether differences in business cycle behaviour are due to differences in the type of shocks that affect the two economies, differences in the propagation mechanism of those shocks, or differences in the way the central bank responds to those economic developments. Our main conclusion is that each of these characteristics is remarkably similar across both currency areas. Copyright © 2005 John Wiley & Sons, Ltd.
Racial differences in adolescent distress: Differential effects of the family and community for blacks and whites
Authors: Wickrama K.A.S. , Noh Samuel , Bryant Chalandra M.
Published: March 2005

Using a sample of 15,885 adolescents derived from the National Longitudinal Study of Adolescent Health, this study examined (1) unique additive influences of race, family, and community and (2) various multiplicative influences among race, family, and community factors on adolescent distress. Community characteristics such as community poverty and ethnic composition were included in the analysis. Community poverty, family poverty, single parenthood, family size, and race/ethnicity all uniquely contributed to adolescent distress. There were significant black–white differences in additive and multiplicative influences of these predictors. The detrimental influence of family poverty was stronger for whites than for blacks. Among blacks, the detrimental influence of community poverty is greater for poor families than for nonpoor families. In contrast, among whites, the detrimental influence of community adversity is greater for nonpoor families than for poor families. Although ethnic composition had no significant impact on adolescent distress for the total sample, it showed a beneficial effect for black adolescents, after controlling for the poverty levels of the communities. Seemingly, community poverty and ethnic composition influence adolescent distress differently through different mechanisms. Understanding these complex processes raise some practical questions about programs aimed at minorities. For example, do black children fare better if their family overcomes persistent poverty and moves out of adverse communities? © 2005 Wiley Periodicals, Inc. J Comm Psychol 33: 261–282, 2005.
Polyaniline with Two Types of Functional Groups: Preparation and Characteristics
Authors: Mu Shaolin
Published: March 2005

Summary: Polyaniline with two types of functional groups (sulfonated poly(aniline‐co‐o‐aminophenol), s‐copolymer) has been prepared by the electrochemical copolymerization of aniline and o‐aminophenol in sulfuric acid solution followed by sulfonation of the copolymer in the concentrated sulfuric acid. There are SO3H groups and OH groups in the s‐copolymer. The presence of SO3H groups on the polymer chain enables the s‐copolymer to possess intrinsic protonic doping ability. The OH group on the polymer chain can be oxidized and reduced reversibly. The shape of the cyclic voltammogram of the s‐copolymer is very similar to that of polyaniline in 0.2 M H2SO4 solution, in the potential range −0.20 to 0.80 V (vs. SCE). The results from cyclic voltammograms indicate only 22.8 and 31.6% decay of the electrochemical activity that was observed when the s‐copolymer electrode was transferred from the solution of pH 5.0 to the solutions of pH 10.0 and 11.0, respectively. Especially, there are still two pairs of redox peaks on the cyclic voltammogram of the s‐copolymer in 0.3 M Na2SO4 solution of pH 11.0 at the scan rate of 6 mV s−1. In this case, its usable potential range is 0.0–0.60 V. The s‐copolymer has a conductivity of 0.85 S cm−1, which is slightly dependent on pH when equilibrated with water. The spectra of FTIR, XPS, and ESR of the s‐copolymer are represented here.

The cyclic voltammograms of (1) poly(aniline‐co‐o‐aminophenol) and (2) s‐copolymer in H2SO4 solution.

magnified image

The cyclic voltammograms of (1) poly(aniline‐co‐o‐aminophenol) and (2) s‐copolymer in H2SO4 solution.
Involvement of protein kinase PKN1 in G2/M delay caused by arsenite
Authors: Isagawa Takayuki , Takahashi Mikiko , Kato Tomohisa , Mukai Hideyuki , Ono Yoshitaka
Published: March 2005

PKN1 is a serine/threonine protein kinase that has been reported to mediate cellular response to stress. We show here that in response to arsenite exposure, PKN1 kinase activity was stimulated, which was associated with increased binding of PKN1 to Cdc25C and delayed mitotic entry. A role for PKN1 in mediating arsenite‐induced G2/M delay was supported by the finding that expression of a constitutively active form of PKN1 (PKN1AF3) in HeLa cells delayed the mitotic entry of cell cycle. Further experiments indicate that PKN1 directly phosphorylated serine 216 (Ser216) in Cdc25C, which then facilitated association between Cdc25C and 14‐3‐3. Significantly, expression of a phosphorylation mutant of Cdc25C (S216A) partially abrogated the cell‐cycle arrest in response to arsenite. Together, our results suggest that PKN1 mediates arsenite‐induced delay of the G2/M transition by binding to and phoshorylating Cdc25C. © 2005 Wiley‐Liss, Inc.
Differential inhibition of UVB‐induced AP‐1 and NF‐κB transactivation by components of the jun bZIP domain
Authors: Cooper Simon , Ranger‐Moore James , Bowden Tim G.
Published: March 2005

Potential targets for chemoprevention of nonmelanoma skin cancer include UV‐induced nuclear factor κB (NF‐κB) and activator protein‐1 (AP‐1) activation in keratinocytes. Inhibition of both these ultraviolet light B (UVB)‐induced transcription factors has been shown with the dominant‐negative c‐jun mutant, TAM67; however, its mechanism of action has not yet been determined. Here we demonstrated that transient transfection of a mouse keratinocyte cell line (308) with a dominant‐negative phosphorylation mutant of c‐Jun before exposure to 250 J/m2 UVB inhibits transactivation mediated by both AP‐1 and NF‐κB transcription factors to levels below those of UVB exposed controls. Through the utilization of immunoprecipitation techniques, protein‐protein interactions between NF‐κB family members IκBα, IκBβ, p50, and p65 (Rel‐A) were identified with an Xpress tagged dominant‐negative c‐Jun (TAM67) protein. Expression of the leucine zipper domain of the TAM67 protein inhibited UVB‐induced NF‐κB transactivation but not AP‐1 transactivation. Expression of the bZIP domain of the TAM67 protein was able to inhibit transactivation mediated by both transcription factors. These data demonstrate that TAM67 is able to inhibit two significant UVB‐induced molecular targets AP‐1 and NF‐κB, and that the inhibition of these two transcription factor families is potentially due to protein‐protein interactions between different regions of the dominant‐negative c‐Jun protein. © 2005 Wiley‐Liss, Inc.
Effects of serotonin 5‐HT1A agonist in advanced Parkinson's disease
Authors: Bara‐Jimenez William , Bibbiani Francesco , Morris Michael J. , Dimitrova Tzvetelina , Sherzai Abdullah , Mouradian Maral M. , Chase Thomas N.
Published: March 2005

Intermittent stimulation of striatal dopaminergic receptors seems to contribute to motor dysfunction in advanced Parkinson's disease (PD). With severe dopaminergic denervation, exogenous levodopa is largely decarboxylated to dopamine in serotonergic terminals. If 5‐HT1A autoreceptors regulate dopamine as well as serotonin release, in parkinsonian patients inhibition of striatal serotonergic neuron firing might help maintain more physiological intrasynaptic dopamine concentrations and thus ameliorate motor fluctuations and dyskinesias. To evaluate this hypothesis, effects of a selective 5‐HT1A agonist, sarizotan, given orally at 2 and 5 mg twice daily to 18 relatively advanced parkinsonian patients, were compared with baseline placebo function during a 3‐week, double‐blind, placebo‐controlled, proof‐of‐concept study. Sarizotan alone or with intravenous levodopa had no effect on parkinsonian severity. But at safe and tolerable doses, sarizotan coadministration reduced levodopa‐induced dyskinesias and prolonged its antiparkinsonian response (P ≤ 0.05). Under the conditions of this study, our findings suggest that 5‐HT1A receptor stimulation in levodopa‐treated parkinsonian patients can modulate striatal dopaminergic function and that 5‐HT1A agonists may be useful as levodopa adjuvants in the treatment of PD. © 2005 Movement Disorder Society
Screening test model using duration of labor for the detection of postpartum urinary retention
Authors: Yip Shing‐Kai , Sahota Daljit , Pang Man‐Wah , Chang Allan
Published: March 2005

Aims

To construct a screening test model for postpartum urinary retention (PUR), using the duration of labor, which was shown to be the risk factor for PUR.

Methods

A group of 691 consecutive patients were recruited at postpartum day 1. Of the 691 patients, 101 (14.6%) had PUR. The 691 patients were computer‐randomized into two groups, ‘A’ and ‘B.’ A receiver operating characteristic (ROC) curve was constructed for Group A to determine the optimum cutoff value for screening PUR using the duration of labor. The cutoff value was then applied to Group B to determine the screening test characteristics of the duration of labor: sensitivity, specificity, predictive values, and likelihood ratios.

Results

An ROC curve with an area under curve (AUC) of 0.63 (95% CI 0.57–0.69, P < 0.0001) was constructed. A range of cutoff values (with specificity ranging from 0.60 to 0.99) for the duration of labor was determined and the test characteristics computed. According to the test characteristics the optimal cutoff value for the duration of labor was 700 min. This cutoff value for the duration of labor has a specificity of 0.95, negative predicative value of 0.86, and likelihood ratio for a positive test of 0.88.

Conclusion

A screening test model using the duration of labor can be constructed to predict PUR. © 2005 Wiley‐Liss, Inc.
Behavioural and psychological symptoms of dementia: clinical aspects
Authors: Bianchetti Angelo , Trabucchi Marco
Published: March 2005

Non cognitive symptoms are almost always present in dementia with important consequences for patients and caregivers quality of life. Behavioural and Psychological Symptoms of Dementia (BPSD) are heterogeneous and varied in relation to the stage of the demetia and to the aetiology. Treatment of behavioral and psychological symptoms of dementia represent an important challenge, and non pharmacological and pharmacological approach needs. Antidepressant and neuroleptics are the most frequently used drugs in the treatment of BPSD, even if the number of well designed controlled studies are limited. A variety of different forms of environmental and rehabilitative interventions showed efficacy on BPSD.
Advance on the diagnostic potential of biological markers in the early detection of Alzheimer Disease
Authors: Borroni Barbara , DiLuca Monica , Cattabeni Flaminio , Padovani Alessandro
Published: March 2005

Here we summarise current knowledge about biological markers available for early Alzheimer Disease detection. In fact delineating disease process from “normal ageing” may be difficult in the very early stages; in later stages of the disease distinguishing Dementia of Alzheimer Type from a number of neurodegenerative diseases associated with dementia may also be troublesome.
The potential role played by artificial adaptive systems in enhancing our understanding of Alzheimer disease: The experience gained within Italian Interdisciplinary network on Alzheimer disease
Authors: Grossi Enzo , Buscema Massimo
Published: March 2005

The author describes a refiguration of medical thought which originate from non linear dynamics and chaos theory. The coupling of computer science and these new theoretical bases allows the creation of “intelligent” agents (Artificial Adaptive Systems AAS) able to adapt themselves dynamically to problem of high complexity like Alzheimer Disease. ASS are able to reproduce the dynamical interactio of multiple factors simultaneously, allowing the study of complexity; they can also draw conclusions on individual basis and not as average trends. In the last years of co‐operation between ITINAD, Bracco Medical Department and Semeion Research Centre different kinds of experiments have been performed with ANNs in Alzheimer Disease context. The specific application of ANN in most cases is original, and has followed two principal aims: –prediction of outcome or diagnosis in individual patients; –data mining of complex data sets. Several examples of applications will be described.
Second‐trimester maternal serum screening for Down syndrome in in vitro fertilization pregnancies
Authors: Rice Jennifer D. , McIntosh Sarah F. , Halstead Anne C.
Published: March 2005

Objectives

To examine whether second‐trimester maternal serum triple marker screening results differ between in vitro fertilization (IVF) pregnancies and naturally conceived pregnancies.

Methods

Second‐trimester maternal serum triple marker screening results from 88 IVF pregnancies were compared with 596 naturally conceived pregnancies (controls). Controls were matched to each IVF pregnancy by maternal age, gestational age and date of blood collection. All pregnancies in the study were known to have normal outcome. Multiple of the median (MoM) levels of human chorionic gonadotrophin (hCG), unconjugated estriol (uE3) and alpha‐fetoprotein (AFP), and the false‐positive rate for Down syndrome were compared between the two groups.

Results

No statistically significant differences in analyte levels or in Down syndrome false‐positive rate were observed between the IVF and naturally conceived pregnancies.

Conclusion

IVF patients can be counselled about maternal serum triple marker screening in the same manner as patients with naturally conceived pregnancies. There is no evidence to support the general use of analyte correction factors in the interpretation of second‐trimester maternal serum screen results in IVF pregnancies. Copyright © 2005 John Wiley & Sons, Ltd.
Ionic Reactions of Chlorinated Volatile Organic Compounds in Air Plasma at Atmospheric Pressure
Authors: Marotta Ester , Scorrano Gianfranco , Paradisi Cristina
Published: March 2005

Summary: Results of the ionic reactivity in air plasma at atmospheric pressure of several important chlorinated VOCs are reported and discussed. These VOCs include saturated (CH2Cl2, CHCl3, CCl4, CH2ClCH2Cl, CHCl2CH3), unsaturated (trichloroethene, Cl2CCHCl) and aromatic (chlorobenzene, C6H5Cl) chloro‐substituted hydrocarbons. The experiments were conducted with a commercial mass spectrometer consisting of a quadrupolar mass analyzer interfaced to an APCI (Atmospheric Pressure Chemical Ionization) ionization source, which uses a corona discharge at atmospheric pressure for the production of a non‐thermal plasma. Some experiments were also conducted with a triple quadrupole mass analyzer in order to study the reactions of specific ions singled out from the plasma on the basis of their characteristic mass/charge ratio. The organic chlorides examined display a few common reactions, such as, most importantly, reductive dissociation to Cl−, but also some ionic reaction channels which are peculiar to the structural features of the specific VOC. Particularly interesting, among the various processes observed and studied, are ionic reactions which might play an important role in the plasma induced oxidative decomposition of VOCs in treatment applications and which involve water, either as the neutral or as the ionic reagent (H3O+), and O.

Positive APCI mass spectra of CCl4 in synthetic air recorded at (a) 30 °C and ΔV = 1 V, (b) 30 °C and ΔV = 150 V and (c) 300 °C and ΔV = 150 V.

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Positive APCI mass spectra of CCl4 in synthetic air recorded at (a) 30 °C and ΔV = 1 V, (b) 30 °C and ΔV = 150 V and (c) 300 °C and ΔV = 150 V.
Negative Coronas: Meaning of Conditioning
Authors: Laan Matti , Repän Villu
Published: March 2005

Summary: The paper clarifies the reasons for long‐term memory effects observed in the case of the low current mode of negative corona. It was found that the temporal changes of the corona characteristics depend on electrode coating, temperature, airflow rate and intensity of UV radiation triggering the discharge. These experimental findings are explained on the basis of the recently developed emission model. Finally, a procedure of the conditioning that guarantees a satisfactory reproducibility of experimental results, is described.

Temporal changes of the photo‐induced current; arrows indicate the moments when UV radiation was switched on/off; airflow rate −4.4 m · s−1.

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Temporal changes of the photo‐induced current; arrows indicate the moments when UV radiation was switched on/off; airflow rate −4.4 m · s−1.
Non‐Thermal Plasma‐Based Technology for Soil Treatment
Authors: Stryczewska Henryka D. , Ebihara Kenji , Takayama Masahiro , Gyoutoku Yutaka , Tachibana Masahiro
Published: March 2005

Summary: Dielectric barrier discharge (DBD) plasma reactors of differing configuration, having a high‐voltage electrode in the form of a screw or pyramid, have been investigated as a potential source of soil treatment agents (ozone and nitric oxide). A special geometry of the high‐voltage electrode allows a relatively large ozone concentration to be obtained both from air and oxygen, which can be controlled by the gas flow rate, cooling conditions, and value and frequency of the supply voltage with reasonable generation efficiency. These results are compared with those generated by a commercially available surface discharge reactor. The resultant properties of treated soils are characterized, such as acidity (pH), electrical conductivity (EC), and content of moisture (pF), nitrogen (NH4N, NO3N), minerals (P2O5, K2O, CaO, MgO, Fe, Mn), and total bacteria and fungi.

The variation of ozone concentration with supply voltage for each of the electrodes studied here.

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The variation of ozone concentration with supply voltage for each of the electrodes studied here.
Oxidant Formation and the Decomposition of Organic Compounds in Foaming Systems
Authors: Pawłat Joanna , Ihara Satoshi , Yamabe Chobei , Pollo Iwo
Published: March 2005

Summary: A foaming apparatus for gas treatment is proposed. Despite a small amount of required liquid, the foaming column can be used not only for polluted gas treatment, but also for a specific type of water and for wastewater purification. In general, the electrical discharge may be applied directly to the foam, partly consisting of pollutant, or before or after the foaming zone or both. In the experiments proposed here, electrical discharge was only used within the foam. Sufficient amounts of various oxidants, high concentrations of hydrogen peroxide (about 50 mg/l), gaseous ozone, dissolved ozone and hydroxyl radicals, were generated using pulse power supply. The reactor was then used for the acetaldehyde treatment and to remove color of wastewaters caused by various pollutants, such as indigo blue, indigo carmine, methylene blue and humic acids.

Cylindrical foaming column (A) and photograph of the reactor (B).

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Cylindrical foaming column (A) and photograph of the reactor (B).
Editorial: race, religion and the census
Authors: Howard David , Hopkins Peter E.
Published: March 2005

The inclusion of a question on religion in the 2001 Census in the UK has renewed interest in the relationship between empirical measurement and the assessment of religious and racialised affiliation. The authors discuss the context of this current debate and introduce a collection of four papers which address these issues. Copyright © 2005 John Wiley & Sons, Ltd.
Relative stability of radicals derived from artemisinin: A semiempirical and DFT study
Authors: Arantes C. , De Araujo M. T. , Taranto A. G. , De M. Carneiro J. W.
Published: March 2005

The semiempirical AM1 and PM3 methods, as well as the density functional (DFT/B3LYP) approach using the 6‐31g(d) basis set, were employed to calculate the relative stability of intermediate radicals derived from artemisinin, a sesquiterpene lactone having an endoperoxide bridge that is essential for its antimalarial activity. The compounds studied have their nonperoxidic oxygen atom of the trioxane ring and/or the carbonyl group replaced by a CH2 unit. Relative stabilities were calculated by means of isodesmic equations using artemisinin as reference. It was found that replacement of oxygen atoms decreases the relative stability of the anionic radical intermediates. In contrast, for compounds with inverted stereochemistry the intermediate radicals were found to be more stable than those with the artemisinin‐like stereochemistry. These relative stabilities may modulate the antimalarial potency. Radicals centered on carbon are always more stable than the corresponding radicals centered on oxygen. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Stereoscopic video images for telerobotic applications
Authors: Ferre Manuel , Aracil Rafael , Navas Manuel
Published: March 2005

This article addresses the use of stereoscopic images in teleoperated tasks. Depth perception is a key point in the ability to skillfully manipulate in remote environments. Displaying three‐dimensional images is a complex process but it is possible to design a teleoperation interface that displays stereoscopic images to assist in manipulation tasks. The appropriate interface for image viewing must be chosen and the stereoscopic video cameras must be calibrated so that the image disparity is natural for the observer. Attention is given to the calculation of stereoscopic image disparity, and suggestions are made as to the limits within which adequate stereoscopic image perception takes place. The authors have designed equipment for image visualization in teleoperated systems. These devices are described and their performance evaluated. Finally, an architecture for the transmission of stereoscopic video images via network is proposed, which in the future will substitute for current image processing devices. © 2005 Wiley Periodicals, Inc.
Projective virtual reality as a basis for on‐line control of complex systems‐not only‐over the internet
Authors: Freund Eckhard , Rossmann Jürgen
Published: March 2005

Already in 1994 the termProjective Virtual Realitywas coined and a first implementation was used to control a complex multirobot system in Germany over the Internet from California. Building on this foundation, the general aim of the development of virtual reality technology for automation applications at the Institute of Robotics Research (IRF) today is to provide the framework forProjective Virtual Realityfor a broad range of applications. The general idea ofProjective Virtual Realityis to allow users to “project” actions carried out in the virtual world into the real world by means of robots or other means of automation. The framework is based on a task‐oriented approach which builds on the “task deduction” capabilities of a newly developed virtual reality system and a task planning component. The advantage of this approach is that robots which work at great distances from the control station can be controlled as easily and intuitively as robots that work right next to the control station. Robot control technology now provides the user in the virtual world with a “prolonged arm” into the physical environment, thus paving the way for intuitive control of complex systems over the Internet—and in general for a new quality of user‐friendly man‐machine interfaces for automation applications. Lately, this work has been enhanced by a new structure that allows one to distribute the virtual reality application over multiple computers on a network. With this new feature, it is now possible for multiple users to share the same virtual room, although they may physically be thousands of miles apart. They only need an Internet connection to share this new experience. Lately, the network distribution techniques have been further developed to not just allow users to cooperate over networked PCs but also to be able to set up a panorama projection or a cave running of a networked cluster of PCs. This approach cuts down the costs for such a high‐end visualization environment drastically and allows for a new range of applications. © 2005 Wiley Periodicals, Inc.