bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of a novel type II classical cadherin: Rat cadherin19 is expressed in the cranial ganglia and Schwann cell precursors during development
Authors: Takahashi Masanori , Osumi Noriko
Published: December 2004

To identify a novel type II classical cadherin, we searched the genome database and found rat cadherin19 (cad19) with high similarity to human cadherin19. We also found nucleotide sequences corresponding to rat cad19 in mouse and chicken genomes. In situ hybridization of rat cad19 revealed that rat cad19 mRNA was initially expressed in cephalic neural crest cells, and then in the cranial ganglia, migrating trunk neural crest cells, the nascent dorsal root ganglia, and the sympathetic ganglia. Expression of cad19 overlapped with that of neural crest markers, including Sox10 and AP‐2, but cad19 expression was confined to subpopulations of the neural crest‐derived cells, those typically observed in the satellite glia at the periphery of the ganglia and Schwann cell precursors along the peripheral nerves. cad19 mRNA was not detected in cells expressing Phox2b, an epibranchial placode‐derived neurons, nor in those expressing neuronal markers such as Hu protein. These observations suggest that cad19 is expressed in neural crest‐derived, non‐neuronal cells. Although the expression of cad19 mRNA persisted in Schwann cell precursors at E14.5, it was no longer detected in maturing Schwann cells at later stages. These results suggest that cad19 is an evolutionarily conserved cadherin and may be involved in the early development of Schwann cells in the peripheral nervous system. Developmental Dynamics 232:200–208, 2005. © 2004 Wiley‐Liss, Inc.
Cellular invasion of the chicken corneal stroma during development: Regulation by multiple matrix metalloproteases and the lens
Authors: Fitch John M. , Kidder J. Michael , Linsenmayer Thomas F.
Published: December 2004

Avian corneal development requires cellular invasion into the acellular matrix of the primary stroma. Previous results show that this invasion is preceded by the removal of the fibril‐associated type IX collagen, which possibly stabilizes matrices through interfibrillar cross‐bridges secured by covalent crosslinks. In the present study, we provide evidence for the expression of three matrix metalloproteinases (MMPs) in early corneas, two of which act cooperatively to selectively remove type IX collagen in situ. In organ cultures, MMP inhibitors (either TIMP‐2 or a synthetic inhibitor) resulted in arrested development, in which collagen IX persisted, and the stroma remained compact and acellular. We also show that blocking covalent crosslinking of collagen allows for cellular invasion to occur, even when the removal of type IX collagen is prevented. Thus, one factor regulating corneal invasion is the physical structure of the matrix, which can be modified by either selective proteolysis or reducing interfibrillar cross‐bridges. We also detected another level of regulation of cellular invasion involving inhibition by the underlying lens. This block, which seems to influence invasive behavior independently of matrix modification, is a transient event that is released in ovo just before invasion proceeds. Developmental Dynamics 232:106–118, 2005. © 2004 Wiley‐Liss, Inc.
Aerogel and Xerogel Catalysts Based on θ‐Alumina Doped with Silicon for High Temperature Reactions
Authors: Popa Aurelien Florin , Courthéoux Laurence , Gautron Eric , Rossignol Sylvie , Kappenstein Charles
Published: December 2004

Numerous materials (supports and catalysts) based on alumina have been prepared using the sol‐gel process and carbon dioxide supercritical drying. In this work two types of solids, i.e. xerogels and aerogels, were systematically compared and a way of introducing platinum metal with a content of 5% percent by weight was examined. The structural data, the surface area, Pt dispersion and catalytic activity for the decomposition of the propellant were measured for the various samples. The (Al2O3)0.88(SiO2)0.12 samples prepared show very interesting porosity values, especially for the aerogel. For this reason, they were chosen as supports for the synthesis of 5 wt% platinum on alumina catalysts. The results presented in this work allowed us to obtain an overall view of the influence of the preparation mode on the properties of platinum on alumina supported catalysts. The dispersion of the metal phase is directly dependent on the specific surface of the support. A significant value for the surface area implies a large amount of centers for interaction with the metal precursor and, consequently, the appearance of more centres of simultaneous germination. Although aerogels obtained by carbon dioxide supercritical drying always show superior properties compared with xerogels, for catalytic decompositions the xerogels still remain superior. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
A cladistic analysis of the Iranian species of the genus Veronica (Scrophulariaceae) with emphasis on the patterns of homoplasy
Authors: Saeidi‐Mehrvarz Shahryar , Zarre Shahin
Published: December 2004

A cladistic analysis of the genus Veronica was performed using 36 morphological characters. 29 species including three outgroups from related genera and 26 species as representatives of natural groups within Veronica distributed mainly in Iran were selected for the analysis. For determination of character polarity the taxa Digitalis nervosa, Wulfenia amherstiana and Veronicastrum virginicum are used as outgroups. Based on the cladistic analysis the patterns of homoplasy are discussed for all applied characters. The analysis shows that most of the morphological characters exhibit high level of homoplasy and are not enough reliable for subgeneric classification in Veronica. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Leaf fungi of two wild plants in Assiut, Egypt
Authors: Hemida S. K.
Published: December 2004

Leaves of two wild species of the flora of Egypt:Calotropis procera(Ait.) Ait.,Asclepiadaceae andChrozophora plicata(Vahl) A.Juss. exSpreng., Euphorbiaceae have been studied morphologically and mycologically, in addtion to air borne fungi. Fifty five species and two varieties belonging to 26 genera of phyllosphere and phylloplane fungi were isolated from both plant species on glucose‐ and cellulose‐agar media. Mycological analysis was done monthly over six months (July to December, 2003).Alternariaalternata, Aspergillus fumigatus, A. flavusandA. nigerwere the basic fungal species found on leaf surfaces. Phylloplane ofC. plicatacaught specificallyChaetomiumglobosum, C. spirale, Cochliobolus lunatus, Drechslera halodes, Fusarium incarnatum,F. oxysporum, Memnoniella echinataandPapulaspora sepedonioides.

The total counts of phyllosphere fungi ofC. plicatawere nearly twice as much as those ofC. proceraregardless medium's type.

Forty species and one variety belonging to 22 genera of air borne fungi were recovered all over the experimental period (six months).Alternaria, Aspergillus,CladosporiumandPenicilliumwere the most frequently isolated species. The presented results revealed that, leaf shape and density (hair density and type) may be the most important factors of the biodiversity of the fungal species on the studied taxa. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Molecular and functional comparison of 1,25‐dihydroxyvitamin D3 and the novel vitamin D receptor ligand, lithocholic acid, in activating transcription of cytochrome P450 3A4
Authors: Jurutka Peter W. , Thompson Paul D. , Whitfield G. Kerr , Eichhorst Kristina R. , Hall Neal , Dominguez Carlos Encinas , Hsieh Jui‐Cheng , Haussler Carol A. , Haussler Mark R.
Published: December 2004

The vitamin D receptor (VDR) binds to and mediates the effects of the 1,25‐dihydroxyvitamin D3 (1,25(OH)2D3) hormone to alter gene transcription. A newly recognized VDR ligand is the carcinogenic bile acid, lithocholic acid (LCA). We demonstrate that, in HT‐29 colon cancer cells, both LCA and 1,25(OH)2D3 induce expression of cytochrome P450 3A4 (CYP3A4), an enzyme involved in cellular detoxification. We also show that LCA‐VDR stimulates transcription of gene reporter constructs containing DR3 and ER6 vitamin D responsive elements (VDREs) from the human CYP3A4 gene. Utilizing gel mobility shift, pulldown, and mammalian two‐hybrid assays, we observe that: (i) 1,25(OH)2D3 enhances retinoid X receptor (RXR) heterodimerization with VDR more effectively than LCA, (ii) the 1,25(OH)2D3‐liganded VDR‐RXR heterodimer recruits full‐length SRC‐1 coactivator, whereas this interaction is minimal with LCA unless LXXLL‐containing fragments of SRC‐1 are employed, and (iii) both 1,25(OH)2D3 and LCA enhance the binding of VDR to DRIP205/mediator, but unlike 1,25(OH)2D3‐VDR, LCA‐VDR does not interact detectably with NCoA‐62 or TRIP1/SUG1, suggesting a different pattern of LCA‐VDR comodulator association. Finally, residues in the human VDR (hVDR) ligand binding domain (LBD) were altered to create mutants unresponsive to 1,25(OH)2D3‐ and/or LCA‐stimulated transactivation, identifying S237 and S225/S278 as critical for 1,25(OH)2D3 and LCA action, respectively. Therefore, these two VDR ligands contact distinct residues in the binding pocket, perhaps generating unique receptor conformations that determine the degree of RXR and comodulator binding. We propose that VDR is a bifunctional regulator, with the 1,25(OH)2D3‐liganded conformation facilitating high affinity endocrine actions, and the LCA‐liganded configuration mediating local, lower affinity cellular detoxification by upregulation of CYP3A4 in the colon. J. Cell. Biochem. 94: 917–943, 2005. © 2004 Wiley‐Liss, Inc.
Reduced‐size polarized basis sets for calculations of molecular electric properties. II. Simulation of the Raman spectra
Authors: Oakes Roma E. , Bell Steven E. J. , Benkova Zuzana , Sadlej Andrzej J.
Published: December 2004

The accuracies of the calculated vibrational frequencies and Raman intensities given by two new, highly compact Pol‐type basis sets, Z2PolX and Z3PolX, have been determined and compared to the 6‐31G(d), PolX, and aug‐cc‐pVTZ basis sets. Calculation of accurate Raman intensities has previously required large basis sets, but the ZmPolX basis sets are smaller even than PolX, which are the most compact basis sets able to calculate accurate Raman intensities. For the largest compound studied, C5H10O2, Z3PolX required more than an order of magnitude less CPU time than PolX, which has been shown to be 10 times faster than aug‐cc‐pVTZ. Two sets of test molecules were studied: one was a series of small molecules for which experimental values for absolute Raman activities were available; the second was a series of medium‐sized molecules (mainly common organic solvents) where only relative Raman band intensities were available. The accuracies of the Raman intensities given by both of the ZmPolX basis sets were good compared to those of the PolX and aug‐cc‐pVTZ sets, and much better than the 6‐31G(d) values. The errors in even unscaled frequency values <2000 cm−1 were also acceptable and were slightly lower for Z3PolX than Z2PolX (30 cm−1 vs. 48 cm−1). The combination of good intensity and frequency data meant that for the medium‐sized organic molecules there was a close correspondence between the simulated Raman spectra and experimental data, and that the observed bands could easily be assigned on the basis of these calculations. Achieving this level of accuracy in the simulations at modest computational cost should now allow computational methods to be combined with experimental Raman studies much more widely than is currently the case. © 2004 Wiley Periodicals, Inc. J Comput Chem 26: 154–159, 2005
Removal of Pb(II) from solution using cellulose‐containing materials
Authors: Shukla SR , Pai Roshan S
Published: December 2004

The potential of cheap cellulose‐containing natural materials such as coir, jute, sawdust and groundnut shells for removal for Pb(II) from aqueous solution of lead nitrate was assessed before and after modifying them with a monochlorotriazine type of dye. The materials showed enhanced adsorption capacity of Pb(II) due to the specific dye loading. This was attributed to chelation and an ion exchange mechanism. The maximum cation uptake values obtained were 0.127, 0.087, 0.090, and 0.106 mmol g−1 for coir, sawdust, jute and groundnut shell in their dyed forms, respectively. The kinetics of both undyed and dyed coir was analysed and the second order rate equation was observed to provide the best correlation of the experimental data. Adsorption isotherm models were developed. The best fit was obtained in the Langmuir model. When subjected to repeated adsorption–desorption cycles, with an intermediate step of mild sodium hydroxide treatment, both dyed and undyed coir retained its adsorptive capacity even after five cycles of reuse. Copyright © 2004 Society of Chemical Industry
Combined radiation therapy and dendritic cell vaccine for treating solid tumors with liver micro‐metastasis
Authors: Chen Zhuang , Xia Dajing , Bi Xuguang , Saxena Anurag , Sidhu Narinder , El‐Gayed Ali , Xiang Jim
Published: December 2004

Background

Tumor metastasis and relapse are major obstacles in combating human malignant diseases. Neither radiotherapy alone nor injection of dendritic cells (DCs) can successfully overcome this problem. Radiation induces tumor cell apoptosis and necrosis, resulting in the release of tumor antigen and danger signals, which are favorable for DC capturing antigens and maturation. Hence, the strategy of combined irradiation and DC vaccine may be a novel approach for treating human malignancies and early metastasis.

Methods

To develop an effective combined therapeutic approach, we established a novel concomitant local tumor and liver metastases model through subcutaneous (s.c.) and intravenous (i.v.) injection. We selected the optimal time for DC injection after irradiation and investigated the antitumor effect of combining irradiation with DC intratumoral injection and the related mechanism.

Results

Combined treatment with radiotherapy and DC vaccine could induce a potent antitumor immune response, resulting in a significant decrease in the rate of local tumor relapse and the numbers of liver metastases. The related mechanisms for this strong antitumor immunity of this combined therapy might be associated with the production of apoptotic and necrotic tumor antigens and heat shock proteins after irradiation, phagocytosis, migration and maturation of DCs, and induction of more efficient tumor‐specific cytotoxic T lymphocyte activity through a cross‐presentation pathway.

Conclusions

Co‐administration of local irradiation and intratumoral DC injection may be a promising strategy for treating radiosensitive tumors and eliminating metastasis in the clinic. Copyright © 2004 John Wiley & Sons, Ltd.
Identification of indigoid dyes in natural organic pigments used in historical art objects by high‐performance liquid chromatography coupled to electrospray ionization mass spectrometry
Authors: Puchalska Maria , Połeć‐Pawlak Kasia , Zadrożna Irmina , Hryszko Helena , Jarosz Maciej
Published: December 2004

Pigments are among the most important components of historical paintings and textiles and their nature provides the unique character of color. They can be divided into two main groups: inorganic and organic, extracted from plants or animals. Their identification is a necessary stage in the conservation of art objects. Reversed‐phase liquid chromatography with electrospray ionization mass spectrometry (ESI‐MS) and UV/visible spectrophotometric methods were elaborated for the identification of indigoid (indigo, indirubin, isoindigo, isoindirubin) color components of natural dyestuffs and their natural or synthetic precursors (indican, isatin, indoxyl, 2‐indolinone). ES‐MS offers detection limits in the range 0.03–5.00 µg ml−1 for the color compounds examined. The method developed made it possible to identify indigo and its isomers in genuine Indian indigo, indigo from woad and Tyrian Purple. It was applied to the identification of natural dyes on fiber from a 19th century Japanese tapestry, ‘Cranes in the landscape’. A procedure based on freezing and grinding of a sample before the extraction of dyes from the textile was developed. The components of the extract obtained were identified after acidic hydrolysis as indigotin and methylene blue. Copyright © 2004 John Wiley & Sons, Ltd.
Fragmentation studies on the antibiotic avilamycin A using ion trap mass spectrometry
Authors: Eichhorn Peter , Pérez Sandra , Bechtholt Andreas , Aga Diana S.
Published: December 2004

A comprehensive study on the fragmentation pattern of the antimicrobial growth promoter avilamycin A was conducted in a quadrupole ion trap mass spectrometer equipped with an electrospray ionization (ESI) source. Performing multiple‐stage experiments on the deprotonated molecule (m/z 1401) and its principal product ions showed that a sequential shortening of the oligosaccharide backbone took place, which can be attributed to the localization of the negative charge in the terminal dichloroisoeverninic acid. Under (+)‐ESI conditions, avilamycin A readily formed an intense sodium‐cationized molecule, [M + Na]+ (m/z 1425). Structural elucidation of the second‐, third‐ and fourth‐generation fragment ions revealed that all of the structures shared a common molecular portion comprising a central monosaccharide. This observation allowed us to assign confidently the complexation site of the alkali metal cation. In addition to the monosodiated molecule, the full‐scan mass spectral acquisition also yielded a less abundant disodiated molecule, [M − H + 2Na]+ (m/z 1447). Multiple‐stage experiments on this ion indicated that the second sodium ion compensates for the negative charge located at either of two positions within the molecule. While deprotonation of the phenolic hydroxyl group in the dichloroisoeverninic acid moiety was suggested to be driven by charge stabilization in the aromatic ring (in analogy with the deprotonated molecule in the (−)‐ESI mode), the deprotonation at an α‐carbon of an ester side‐chain substituent in the oligosaccharide part was believed to provide a stable chelation‐like coordination site for the cation. Copyright © 2004 John Wiley & Sons, Ltd.
Movement disorder emergencies
Authors: Kipps Christopher M. , Fung Victor S.C. , Grattan‐Smith Padraic , de Moore Gregory M. , Morris John G.L.
Published: December 2004

Movement disorders may present acutely, and failure to recognize and exclude important differential diagnoses can result in significant morbidity or mortality. Unfortunately, much of the literature pertaining to this topic is scattered and not easily accessible. This review aims to address this deficit. Movement disorder emergencies are discussed according to their most likely mode of presentation. Diagnostic considerations and early management principles are reviewed, along with appropriate pathophysiology where relevant. © 2004 Movement Disorder Society
Novel parkin mutations detected in patients with early‐onset Parkinson's disease
Authors: Bertoli‐Avella Aida M. , Giroud‐Benitez José L. , Akyol Ali , Barbosa Egberto , Schaap Onno , van der Linde Herma C. , Martignoni Emilia , Lopiano Leonardo , Lamberti Paolo , Fincati Emiliana , Antonini Angelo , Stocchi Fabrizio , Montagna Pasquale , Squitieri Ferdinando , Marini Paolo , Abbruzzese Giovanni , Fabbrini Giovanni , Marconi Roberto , Dalla Libera Alessio , Trianni Giorgio , Guidi Marco , De Gaetano Antonio , Boff Maegawa Gustavo , De Leo Antonino , Gallai Virgilio , de Rosa Giulia , Vanacore Nicola , Meco Giuseppe , van Duijn Cornelia M. , Oostra Ben A. , Heutink Peter , Bonifati Vincenzo ,   The Italian Parkinson Genetics Network, MD
Published: December 2004

A multiethnic series of patients with early‐onset Parkinson's disease (EOP) was studied to assess the frequency and nature of parkin/PARK2 gene mutations and to investigate phenotype–genotype relationships. Forty‐six EOP probands with an onset age of <45 years, and 14 affected relatives were ascertained from Italy, Brazil, Cuba, and Turkey. The genetic screening included direct sequencing and exon dosage using a new, cost‐effective, real‐time polymerase chain reaction method. Mutations were found in 33% of the indexes overall, and in 53% of those with family history compatible with autosomal recessive inheritance. Fifteen parkin alterations (10 exon deletions and five point mutations) were identified, including four novel mutations: Arg402Cys, Cys418Arg, IVS11‐3C>G, and exon 8‐9‐10 deletion. Homozygous mutations, two heterozygous mutations, and a single heterozygous mutation were found in 8, 6, and 1 patient, respectively. Heterozygous exon deletions represented 28% of the mutant alleles. The patients with parkin mutations showed significantly earlier onset, longer disease duration, more frequently symmetric onset, and slower disease progression than the patients without mutations, in agreement with previous studies. This study confirms the frequent involvement of parkin and the importance of genetic testing in the diagnostic work‐up of EOP. © 2004 Movement Disorder Society
Viscous compressible barotropic symmetric flows with free boundary under general mass force Part I: Uniform‐in‐time bounds and stabilization
Authors: Ducomet Bernard , Zlotnik Alexander
Published: December 2004

We consider symmetric flows of a viscous compressible barotropic fluid with a free boundary, under a general mass force depending both on the Eulerian and Lagrangian co‐ordinates, with arbitrarily large initial data. For a general non‐monotone state function p, we prove uniform‐in‐time energy bound and the uniform bounds for the density ρ, together with the stabilization as t → ∞ of the kinetic and potential energies. We also obtain H1‐stabilization of the velocity v to zero provided that the second viscosity is zero. For either increasing or non‐decreasing p, we study the Lλ‐stabilization of ρ and the stabilization of the free boundary together with the corresponding ω‐limit set in the general case of non‐unique stationary solution possibly with zones of vacuum. In the case of increasing p and stationary densities ρS separated from zero, we establish the uniform‐in‐time H1‐bounds and the uniform stabilization for ρ and v. All these results are stated and mainly proved in the Eulerian co‐ordinates. They are supplemented with the corresponding stabilization results in the Lagrangian co‐ordinates in the case of ρS separated from zero. Copyright © 2005 John Wiley & Sons, Ltd.
Botulinum toxin for the treatment of lower urinary tract symptoms: A review
Authors: Sahai A. , Khan M. , Fowler C.J. , Dasgupta P.
Published: December 2004

Aims

To review the available literature on the application of botulinum toxin in the urinary tract, with particular reference to its use in treating detrusor overactivity (DO).

Methods

Botulinum toxin, overactive bladder (OAB), detrusor instability, DO, detrusor sphincter dyssynergia (DSD), and lower urinary tract dysfunction were used on Medline Services as a source of articles for the review process.

Results

DO poses a significant burden on patients and their quality of life. Traditionally patients have been treated with anti‐cholinergic drugs if symptomatic, however, a significant number find this treatment either ineffective or intolerable due to side effects. Recent developments in this field have instigated new treatment options, including botulinum toxin, for patients' refractory to first line medication. Botulinum toxin, one of the most poisonous substances known to man, is a neurotoxin produced by the bacterium Clostridium botulinum. Botulinum toxin injections into the external urethral sphincter to treat detrusor sphincter dyssynergia has been successfully used for some years but recently its use has expanded to include voiding dysfunction. Intradetrusal injections of botulinum toxin into patients with detrusor overactivity and symptons of the overactive bladder have resulted in significant increases in mean maximum cystometric capacity and detrusor compliance with a reduction in mean maximum detrusor pressures. Subjective and objective assessments in these patients has shown significant improvements that last for 9–12 months. Repeated injections have had the same sustained benefits.

Conclusions

Application of botulinum toxin in the lower urinary tract has produced promising results in treating lower urinary tract dysfunction, which needs further evaluation with randomised, placebo‐controlled trials. © 2004 Wiley‐Liss, Inc.
Two dimensional mortar contact methods for large deformation frictional sliding
Authors: Yang Bin , Laursen Tod A. , Meng Xiaonong
Published: December 2004

This paper presents a mortar‐based formulation for the solution of two dimensional frictional contact problems involving finite deformation and large sliding. As is widely recognized, traditional node‐to‐surface contact formulations have several drawbacks in solution of deformable‐to‐deformable contact problems, including lack of general patch test passage, degradation of spatial convergence rates, and robustness issues associated with the faceted representation of contacting surfaces. The mortar finite element method, initially proposed as a technique to join dissimilarly meshed domains, has been shown to preserve optimal convergence rates in tied contact problems (see (Discretization Methods and Iterative Solvers Based on Domain Decomposition, Springer‐Verlag, Heidelberg, 2001) for a recent review), and is examined here as an alternative spatial discretization method for large sliding contact. In particular, a novel description for frictional sliding conditions in large deformation mortar formulations is proposed in this work.

In recent years, the mortar element method has already been successfully implemented to solve frictional contact problems with linearized kinematics (see (Int. J. Numer. Meth. Engng 1993; 36: 3451)). However, in the presence of large deformations and finite sliding, one must face difficulties associated with the definition and linearization of contact virtual work in the case where the mortar projection has a direct dependence on the tangential relative motion along the interface. In this paper, such a formulation is presented, with particular emphasis on key aspects of the linearization procedure and on the robust description of the friction kinematics. Some novel techniques are proposed to treat the non‐smoothness in the contact geometry and the searching required to define mortar segments. A number of numerical examples illustrate the performance and accuracy of the proposed formulation. Copyright © 2004 John Wiley & Sons, Ltd.
The specificity of public service reform
Authors: Caiden Gerald E. , Sundaram Pachampet
Published: December 2004

Despite universal recognition of the decline of public services and the need for reforms, considerable divergence of views exists on the strategy and sequencing of reform for individual countries according to their capacities and level of development. This article reflects on the general contours of public service reform, emphasising past experience, the need to be pragmatic rather than idealistic, the mudding of the waters by the New Public Management movement, the complications of structural adjustment programmes of international financial institutions and the damage resulting from the imposition of universal solutions unfitted and unsuitable to local circumstances. Reform needs political and bureaucratic champions, careful preparation, patience and necessary investment, and capacity to neutralise opposition. Ultimately, one has to allow for a shifting combination of history, culture, politics, economics, sociology, ideology and values in each country.

This analysis is applied to the possibility of reforming the public service of India, the second most populous country in the world, and the lessons to be gleaned for developing and implementing the strategy.

The article then concludes with an outline of some universal problems facing public service reformers all around the globe such as corruption, the future role of government, shape of the civil service, reversing its erosion and addressing issues of fragmentation, compensation and diversity. Copyright © 2004 John Wiley & Sons, Ltd.
Compatible thermoplastic starch/polyethylene blends by one‐step reactive extrusion
Authors: Wang Shujun , Yu Jiugao , Yu Jinglin
Published: December 2004

In the presence of dicumyl peroxide (DCP), the thermal plasticization of starch and its compatibilizing modification with polyethylene was accomplished by one‐step reactive extrusion in a single‐screw extruder at the same time. Because of the formation of polyethylene‐graft‐maleic anhydride (PE‐g‐MAH) during the extrusion, it was used as the compatibilizer between the thermoplastic starch and polyethylene. The blending samples were characterized by means of thermogravimetric analysis (TGA), scanning electron microscopy (SEM), dynamic thermal mechanical analysis (DTMA) and Fourier‐transform infrared (FTIR) analysis. The experimental results showed that in the presence of DCP the addition of MAH improved the mutual dispersion of molecules in thermoplastic starch and polyethylene. From TGA, we concluded that the thermal stability of the blends with MAH was improved compared with the blends without MAH. The DTMA and FTIR results indicated that, with the addition of MAH, the compatibility of molecules between thermoplastic starch and polyethylene in the blends was improved. Copyright © 2004 Society of Chemical Industry
Polymerization and carbonization of high internal phase emulsions
Authors: Wang Dong , Smith Naomi L , Budd Peter M
Published: December 2004

High internal phase emulsions (HIPEs) of styrene and divinylbenzene (DVB), with 0–40 % vinylbenzyl chloride (VBC) in the oil phase, were polymerized to give porous polymers (pore volumes 84–92 %), which were sulfonated and carbonized at temperatures up to 700 °C to obtain macroporous carbon monoliths. On carbonization, overall sample dimensions decreased, whilst percentage pore volume, compressive strength and compressive modulus increased. Scanning electron microscopy (SEM) showed typical HIPE‐derived structures of cages (several µm across), interconnected by smaller windows, for polymer and carbon samples. Distributions of cage and window size were evaluated from electron micrographs. Average cage and window sizes decreased on carbonization approximately in proportion to the reduction in overall sample dimensions, and also decreased with increasing VBC content in the HIPE. Mercury intrusion porosimetry gave distributions of pore size in reasonable agreement with area‐distributions of window size determined from SEM images. Copyright © 2004 Society of Chemical Industry
Photocurable biodegradable polyesters from poly(L‐lactide) diols
Authors: Nagata Minoru , Sato Yuki
Published: December 2004

α,ω‐Dihydoxy‐terminated poly(L‐lactide)s (PLLA diols) with various molecular weights (1000, 2000 and 3000 g mol−1) were prepared by the ring‐opening polymerization of L‐lactide using 1,6‐hexanediol as an initiator. These were subsequently chain‐extended with the diacyl chloride of 4,4′‐(adipoyldioxy)dicinnamic acid (CAC) to obtain high‐molecular‐weight photocurable polyesters (CAC/PLLAs). The resulting polyesters were characterized by gel permeation chromatography, Fourier‐transform infrared, ultraviolet–visible and proton nuclear magnetic resonance spectroscopies, differential scanning calorimetry and thermogravimetry. These photoreactive polyesters were irradiated with a high‐pressure mercury lamp (λ > 280 nm) for 30–180 min to produce the crosslinked polyesters. The gel fraction yield increased with photocuring time, and exceeded 80 % after 180 min. The photocuring process disturbed the crystallization of the CAC/PLLA films, while it enhanced their thermal stabilities. With increasing photocuring time, both the tensile strength and modulus increased markedly. The best mechanical properties (tensile strength = 41 MPa; tensile modulus = 1550 MPa) were obtained for a CAC/PLLA‐3000 film photocured for 180 min. The tensile modulus of this photocured film was larger than that of pure PLLA. The hydrolytic degradation rates of the CAC/PLLA films in a phosphate buffer solution (pH, 7.2) of proteinaze‐k at 37 °C were much slower than those of pure PLLA films. Copyright © 2004 Society of Chemical Industry
High‐performance waterborne coatings based on epoxy‐acrylic‐graft‐copolymer‐modified polyurethane dispersions
Authors: Parmar Randhir , Patel Kalpesh , Parmar Jayant
Published: December 2004

Polyurethane dispersions (PUDs) have been an active area of research since the early 1940s because of legislative restrictions on the use of organic solvents in conventional solvent‐based products and also because PUDs exhibit almost the same high performance levels as solvent‐borne polyurethanes. In the present study, properties of conventional waterborne PUDs are modified with epoxy‐acrylic graft copolymer blocks. The epoxy‐acrylic graft copolymers were first modified with ethylene diamine to give amine‐terminated blocks which in turn reacted with isocyanate‐terminated prepolymer (prepolymer mixing process) to give modified PUDs. Several experimental sets were prepared with varying compositions. The experimental sets were also prepared using conventional poly(ethylene glycol) blocks and ethylene diamine chain‐extenders. The physico‐chemical properties and film characteristics of the experimental sets show the dramatic improvement in important mechanical properties of PUDs due to grafting with epoxy‐acrylic copolymer blocks. Copyright © 2004 Society of Chemical Industry
Thermal and crystallization behavior of silane‐crosslinked polypropylene
Authors: Wang Zhengzhou , Wu Xiusheng , Gui Zhou , Hu Yuan , Fan Weicheng
Published: December 2004

Silane‐crosslinked polypropylene (PP) has been prepared first by the grafting of silane onto the backbone of PP in a melt process and then by crosslinking in warm water. The effects of type and concentration of silane and peroxide on the silane grafting on PP were investigated. The thermal behavior of the silane‐crosslinked PP was studied by thermogravimetric (TG) and differential scanning calorimetry (DSC) methods. TG results show that PP prepared via silane crosslinking increases its thermal stability greatly. It has been found from DSC measurements that the crystallization temperatures, ie the onset temperature and peak temperature of the exotherm of the silane‐crosslinked PP, increase compared with those of the pure PP. The silane crosslinking hardly changes the crystallinity degree of PP. The crystallization behavior of the silane‐crosslinked PP was also studied by wide‐angle X‐ray diffraction analysis. Copyright © 2004 Society of Chemical Industry
Radiation contribution to the thermal conductivity of plastic foams
Authors: De Micco C. , Aldao C. M.
Published: December 2004

The validity of two approaches widely used to determine the radiant thermal conductivity in plastic foams is discussed. While one approach is based on the solution of a geometric model, the other is derived from the experimental determination of the extinction coefficient. A comparison to recently reported experimental data shows that the geometric approach predicts values that are in good agreement. In contrast, values deduced from measurements of the mean extinction coefficient significantly underestimate the radiant thermal conductivity, an effect that can be traced to the way that the extinction coefficient is measured. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 190–192, 2005
Cyber security risk analysis for process control systems using rings of protection analysis (ROPA)
Authors: Baybutt Paul
Published: December 2004

Process plants may be subject to terrorist and criminal acts that can cause harm such as the release or diversion of hazardous materials and process or product damage. Such risks are evaluated using threat and vulnerability analysis and possible improvements in security measures and safeguards are identified. However, recommendations for improvements are usually based on engineering judgment. Such subjective assessments can lead to disagreements, and possibly inappropriate measures to reduce risk. Rings of Protection Analysis (ROPA), a simplified risk assessment method, can be used to provide more rational, objective, and reproducible decisions. ROPA parallels Layers of Protection Analysis (LOPA) that is used to evaluate accident risks.

ROPA assists in identifying and determining the adequacy of existing protection systems. It is used to help determine whether there are sufficient rings/layers of protection against a threat scenario and whether the risk can be tolerated. A scenario may require multiple protection rings/layers depending on the process and the potential severity of the consequences. ROPA helps provide the basis for clear, functional specifications of required protection layers.

This paper describes and demonstrates how ROPA can be applied to cyber security, although it can also be applied to physical security. It considers the selection of security measures and integrates their consideration with other types of protective measures. © 2004 American Institute of Chemical Engineers Process Saf Prog, 2004
Lifetime of nonequilibrium carriers in high‐Al‐content AlGaN epilayers
Authors: Mickevičius J. , Aleksiejūnas R. , Shur M. S. , Tamulaitis G. , Qhalid Fareed R. S. , Zhang J. P. , Gaska R. , Khan M. A.
Published: December 2004

AlGaN epilayers with different aluminum molar fractions have been comparatively studied by photoluminescence (PL) and light‐induced transient grating (LITG) techniques. The carrier diffusion length determined by LITG is shown to be close to the average distance between two first‐neighbor dislocations, which was roughly estimated by using the dislocation density obtained by etch pit technique. For epilayers containing the same amount of Al, the carrier lifetime and PL intensity are inversely proportional to the density of the dislocations, which limit the carrier lifetime by serving as nonradiative recombination centers. For AlGaN epilayers with similar lifetimes but with different Al contents, the PL intensity decreases with increasing Al fraction, which is explained by the Al content dependence of the radiative recombination rate. It is demonstrated that introduction of AlN/AlGaN superlattices on sapphire substrates by using Migration Enhanced Metal Organic Chemical Vapor Deposition (MEMOCVDTM) enables growth of AlGaN with an increased nonequilibrium carrier lifetime and enhanced photoluminescence intensity. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Principal component analysis of the effects of wavefunction modification on the electrostatic potential of indole
Authors: Carvalho Maíra A. , Da Silva João Bosco P. , Hernandes Marcelo Z.
Published: December 2004

The molecular electrostatic potential (MEP) of the indole molecule was calculated in a three‐dimensional grid in which the molecule was centered at the origin. To evaluate the dependence of MEP on the type of calculation, semiempirical, ab initio, and density functional theory methods with different basis sets were employed. The data matrix generated by these calculations was analyzed by principal component analysis (PCA). The appearance of outliers and the effect of wavefunction modifications such as the introduction of electron correlations and diffuse functions were highlighted by the use of PCA. The spatial localization of such effects around the molecule was possible from the loadings values associated with the graphical analysis of the grid points. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
B3LYP, BLYP and PBE DFT band structures of the nucleotide base stacks
Authors: Szekeres Zs. , Bogár F. , Ladik J.
Published: December 2004

DFT crystal orbital (band structure) calculations have been performed for the nucleotide base stacks of cytosine, thymine, adenine, and guanine arranged in DNA B geometry. The band structures obtained with PBE, BLYP, and B3LYP functionals are presented and compared to other related experimental and theoretical results. The influence of the quality of the basis set on the fundamental gap values was also investigated using Clementi's double ζ, 6‐31G and 6‐31G* basis sets. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Simultaneous determination of beta‐blocking agents and diuretics in doping analysis by liquid chromatography/mass spectrometry with scan‐to‐scan polarity switching
Authors: Deventer K. , Van Eenoo P. , Delbeke F. T.
Published: December 2004

A previously described method for the screening of 18 diuretics and probenecid was substantially extended with 21 beta‐blockers and 8 other diuretics allowing simultaneous determination of diuretics and beta‐adrenergic blocking agents in human urine. Analysis was performed using an ion trap instrument with an electrospray ionisation (ESI) interface after liquid/liquid extraction with ethyl acetate. Full‐scan MS and full‐scan MS2 were applied in combination with scan‐to‐scan polarity switching. All compounds were separated in less than 22 min. The detection limits for the diuretics were between 5 and 100 ng/mL and for the beta‐adrenergic blocking agents were between 5 and 500 ng/mL. The excretion of carvedilol was followed after intake of one tablet of Dimitone®. Other doping agents including strychnine, norbuprenorphine and mesocarb hydroxysulfate could also be detected with this method. Copyright © 2004 John Wiley & Sons, Ltd.
Gas chromatography/ion trap mass spectrometry applied for the determination of polybrominated diphenyl ethers in soil
Authors: Wang Dongli , Cai Zongwei , Guibin Jiang  , Wong Ming Hung , Wong Wai Kwok
Published: December 2004

A gas chromatography/ion trap mass spectrometry (GC/ITMS) method was developed for the determination of polybrominated diphenyl ethers (PBDEs). ITMS parameters were optimized in order to achieve the best sensitivity for the PBDE analysis. Tandem mass spectrometry, along with an isotope dilution internal standard method, was used for the quantitation. Chromatographic windows were developed for mono‐ to hepta‐BDEs, depending on the retention times when a 30‐m GC column was used. A different 15‐m column was used to analyze deca‐BDE. Environmental soil samples collected from an electronic waste recycling site were prepared by using Soxhlet extraction and column chromatographic cleanup. Average recoveries of 61–118% were obtained for the 13C‐labeled PBDE internal standards spiked in the samples prior to sample preparation. The accuracy represented by relative analytical errors was −24% to 18%, and the precision (relative standard deviation) was 11–26% (n = 8). The method detection limits ranged from 0.013–0.25 ng/g for the PBDEs in soil. Copyright © 2004 John Wiley & Sons, Ltd.
Identification and impact of outcome selection bias in meta‐analysis
Authors: Williamson P. R. , Gamble C.
Published: December 2004

The systematic review community has become increasingly aware of the importance of addressing the issues of heterogeneity and publication bias in meta‐analyses. A potentially bigger threat to the validity of a meta‐analysis appears relatively unnoticed. The within‐study selective reporting of outcomes, defined as the selection of a subset of the original variables recorded for inclusion in publication of trials, can theoretically have a substantial impact on the results.

A cohort of meta‐analyses on the Cochrane Library was reviewed to examine how often this form of within‐study publication bias was suspected and explained some of the evident funnel plot asymmetry. In cases where the level of suspicion was high, sensitivity analysis was undertaken to assess the robustness of the conclusion to this bias. Although within‐study selection was evident or suspected in several trials, the impact on the conclusions of the meta‐analyses was minimal.

This paper deals with the identification of, sensitivity analysis for, and impact of within‐study selective reporting in meta‐analysis. Copyright © 2004 John Wiley & Sons, Ltd.
Using generalized additive models to reduce residual confounding
Authors: Benedetti Andrea , Abrahamowicz Michal
Published: December 2004

Traditionally, confounding by continuous variables is controlled by including a linear or categorical term in a regression model. Residual confounding occurs when the effect of the confounder on the outcome is mis‐modelled. A continuous representation of a covariate was previously shown to result in a less biased estimate of the adjusted exposure effect than categorization provided the functional form of the covariate–outcome relationship is correctly specified. However, this is rarely known. In contrast to parametric regression, generalized additive models (GAM) fit a smooth dose–response curve to the data, without requiringa prioriknowledge of the functional form.

We used simulations to compare parametric multiple logistic regression vs its non‐parametric GAM extension in their ability to control for a continuous confounder. We also investigated several issues related to the implementation of GAM in this context, including: (i) selecting the degrees of freedom; and (ii) alternative criteria for inclusion/exclusion of the potential confounder and for choosing between parametric and non‐parametric representation of its effect. The impact of the shape and strength of the confounder–disease association, sample size, and the correlation between the confounder and exposure were investigated.

Simulations showed that when the confounder has a non‐linear association with the outcome, compared to a parametric representation, GAM modelling (i) reduced the mean squared error for the adjusted exposure effect; (ii) avoided inflation of the type I error for testing the exposure effect. When the true confounder–outcome relationship was linear, GAM performed as well as the parametric logistic regression.

When modelling a continuous exposure non‐parametrically, in the presence of a continuous confounder, our results suggest that assuming a linear effect of the confounder and focussing on the non‐linearity of the exposure–outcome relationship leads to spurious findings of non‐linearity: joint non‐linear modelling is necessary.

Overall, our results suggest that the use of GAM to reduce residual confounding offers several improvements over conventional parametric modelling. Copyright © 2004 John Wiley & Sons, Ltd.
Controversies concerning randomization and additivity in clinical trials
Authors: Senn Stephen
Published: December 2004

‘As ye randomise so shall ye analyse’, is one way of describing Fisher's defence of randomization. Yet, when it comes to clinical trials we nearly always randomize but we rarely analyse the way we randomize and Fisher himself was no exception. Two controversies involving Fisher in the 1930s are discussed: one with Neyman concerning additivity and the other with Student concerning randomization. Their relevance today is considered, as is whether randomization inference in clinical trials is dead and whether modelling rules the day, whether minimization is an acceptable procedure and to what extent trialists confuse experiments with surveys. It will be maintained that a number of different possible purposes of clinical trials have been confused because in the case of the general linear model, under strong additivity, they can all be satisfied by a single analysis. More generally, however, this is not the case. Copyright © 2004 John Wiley & Sons, Ltd.
One‐dimensional Europium(III) Coordination Polymer Based on 3‐Pyridylacrylic Acid
Authors: Liu Yu‐Juan , Xiong Ren‐Gen , You Xiao‐Zeng , Che Chi‐Ming
Published: December 2004

Under hydrothermal conditions, the reaction of racemic 3‐pyridyl‐3‐aminopropionic acid (rac‐HPAPA) with Eu(ClO4)3· 6H2O affords a 1‐D chain complex, [Eu(3‐PYA)3(H2O)]n (1) (3‐PYA=3‐pyridylacrylate), which represents an example of neutral 1‐D coordination polymeric material based on 3‐HPYA (HPYA= pyridylacrylic acid) ligand with strong red fluorescent emission in the solid state.