bluuebunny/crossref_metadata_2025 huggingface dataset:
Collagen fibril assembly during postnatal development and dysfunctional regulation in the lumican‐deficient murine cornea
Authors: Chakravarti Shukti , Zhang Guiyun , Chervoneva Inna , Roberts Luke , Birk David E.
Published: June 2006

The transparent cornea is the outer barrier of the eye and is its major refractive surface. Development of a functional cornea requires a postnatal maturation phase involving development, growth and organization of the stromal extracellular matrix. Lumican, a leucine‐rich proteoglycan, is implicated in regulating assembly of collagen fibrils and the highly organized extracellular matrix essential for corneal transparency. We investigated the regulatory role(s) of lumican in fibril assembly during postnatal corneal development using wild type (Lum+/+) and lumican‐null (Lum−/−) mice. In Lum+/+ mice, a regular architecture of small‐diameter fibrils is achieved in the anterior stroma by postnatal day 10 (P10), while the posterior stroma takes longer to reach this developmental maturity. Thus, the anterior and the posterior stroma follow distinct developmental timelines and may be under different regulatory mechanisms. In Lum−/− mice, it is the posterior stroma where abnormal lateral associations of fibrils and thicker fibrils with irregular contours are evident as early as P10. In contrast, the anterior stroma is minimally perturbed by the absence of lumican. In Lum+/+ mice, lumican is expressed throughout the developing stroma at P10, with strong expression limited to the posterior stroma in the adult. Therefore, the posterior stroma, which is most vulnerable to lumican‐deficiency, demonstrates an early developmental defect in fibril structure and architecture in the Lum−/− mouse. These defects underlie the reported increased light scattering and opacity detectable in the adult. Our findings emphasize the early regulation of collagen structure by lumican during postnatal development of the cornea. Developmental Dynamics 235:2493–2506, 2006. © 2006 Wiley‐Liss, Inc.
Mathematical model of morphogen electrophoresis through gap junctions
Authors: Esser Axel T. , Smith Kyle C. , Weaver James C. , Levin Michael
Published: June 2006

Gap junctional communication is important for embryonic morphogenesis. However, the factors regulating the spatial properties of small molecule signal flows through gap junctions remain poorly understood. Recent data on gap junctions, ion transporters, and serotonin during left–right patterning suggest a specific model: the net unidirectional transfer of small molecules through long‐range gap junctional paths driven by an electrophoretic mechanism. However, this concept has only been discussed qualitatively, and it is not known whether such a mechanism can actually establish a gradient within physiological constraints. We review the existing functional data and develop a mathematical model of the flow of serotonin through the early Xenopus embryo under an electrophoretic force generated by ion pumps. Through computer simulation of this process using realistic parameters, we explored quantitatively the dynamics of morphogen movement through gap junctions, confirming the plausibility of the proposed electrophoretic mechanism, which generates a considerable gradient in the available time frame. The model made several testable predictions and revealed properties of robustness, cellular gradients of serotonin, and the dependence of the gradient on several developmental constants. This work quantitatively supports the plausibility of electrophoretic control of morphogen movement through gap junctions during early left–right patterning. This conceptual framework for modeling gap junctional signaling—an epigenetic patterning mechanism of wide relevance in biological regulation—suggests numerous experimental approaches in other patterning systems. Developmental Dynamics 235:2144–2159, 2006. © 2006 Wiley‐Liss, Inc.
Restricted expression of Fgf16 within the developing chick inner ear
Authors: Chapman Susan C. , Cai Qin , Bleyl Steven B. , Schoenwolf Gary C.
Published: June 2006

Fibroblast growth factor (FGF) signaling is required for otic placode induction and patterning of the developing inner ear. We have cloned the chick ortholog of Fgf16 and analyzed its expression pattern in the early chick embryo. Expression is restricted to the otic placode and developing inner ear through all the stages examined. By the closed otocyst stage, expression has resolved to anterior and posterior domains that partially overlap with those of bone morphogenetic protein 4 (Bmp4), a marker of the developing sensory patches, the cristae of the anterior and posterior semicircular canals. Platelet‐derived growth factor alpha (PDGFA), another growth factor with restricted otic expression, also overlaps with Fgf16 expression. The restricted expression pattern of Fgf16 suggests a role for FGF signaling in the patterning of the sensory cristae, together with BMP signaling. Developmental Dynamics 235:2276–2281, 2006. © 2006 Wiley‐Liss, Inc.
Optimized cationic lipid‐based gene delivery reagents for use in developing vertebrate embryos
Authors: deCastro Michael , Saijoh Yukio , Schoenwolf Gary C.
Published: June 2006

We have used cationic lipid‐based transfection reagents for ectopic gene expression experiments in developing vertebrate embryos. Lipofectamine, Lipofectamine 2000, and Lipofectamine enhanced with a disulfide linked pegylated lipid (mPEG‐SS‐DOPE) were initially tested and optimized in cell culture. Two reagent formulations, 1:4 (DNA:Lipofectamine 2000) Lipofectamine 2000, and 7.5% pegylated Lipofectamine, produced the highest levels of gene expression in vitro. Those formulations, containing the enhance green fluorescent protein reporter gene, were microinjected into intact vertebrate embryos—systemically through the vasculature and locally into selected tissues—to assess in vivo transfection efficiency. Whereas both formulations are capable of transfecting cells in developing embryos in vivo, greater transfection efficiencies in a broader range of tissue types were obtained with the pegylated Lipofectamine formulation. We conclude that in developing vertebrate embryos, optimized cationic lipid‐based reagents are capable of producing significant levels of ectopic gene expression and can be used as alternatives to electroporation and viral‐mediated gene delivery. Developmental Dynamics 235:2210–2219, 2006. © 2006 Wiley‐Liss, Inc.
Magnetic characteristics of electromagnetic levitation system for short‐radius curve track
Authors: Nomiyama Takuma , Kakinoki Toshio , Yamaguchi Hitoshi , Jifuku Yorito , Mochizuki Takuro
Published: June 2006

A magnetically levitated (MAGLEV) vehicle using electromagnets and iron rails generates lateral guiding force naturally by controlling levitation force to maintain the air gaps between the magnets and the iron rails. A MAGLEV system without guide magnets offers simple design and cost advantages. But such a system has little lateral damping force. In order to improve damping characteristics, an experimental apparatus using salient‐pole‐type magnets and laminated iron rails was made. The iron cores were placed in two rows. The suspension coils surrounded both of the magnet iron cores and the damping coils surrounded every magnet core separately. The damping coils were excited by currents proportional to the lateral displacement velocity. According to a step response experiment, the lateral motion dissipated after a cycle or two of the swing. The self‐inductance of the suspension coil of the magnet was almost unchanged against variation of the lateral displacement. The influence of damping current on the levitation was very small. This paper discusses the electromagnetic characteristics of the levitation system. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 156(3): 71–80, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20372
A study on configuration of oscillator circuits for improving phase noise
Authors: Sakuta Yukinori , Arai Yuji , Sekine Yoshifumi
Published: June 2006

The advancement of communication technology in recent years demands the technology of the high frequency and low phase noise of oscillators required for mobile telecommunications. In general, there are two important designs for improving the phase noise characteristics of the oscillator. One is a design where the phase noise in the amplifier is suppressed to low. The other is a design having loaded Q as large as possible. In this paper we discuss a configuration of oscillator circuit to obtain an extremely low phase noise and an oscillator operating at a nonreactive frequency of SAW resonator. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 156(3): 48–54, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20380
Congestion control for TCP/AQM networks using state predictive control
Authors: Azuma Takehito , Fujita Tsunetoshi , Fujita Masayuki
Published: June 2006

The purpose of this paper is to design congestion controllers for TCP/AQM networks using state predictive control and to illustrate the effectiveness of the resulting congestion controllers via SIMULINK and the ns‐2 simulator. Linearized models of TCP/AQM networks can be simply described as linear systems with information delay. Using state predictive control, these linear systems with an information delay are equivalent to linear systems with no delay. Thus, congestion controllers (AQM mechanisms) can be designed by using linear control theory. In this paper, LQ control with an observer is adopted for linear systems with no delay which describe linearized systems of TCP/AQM networks. Finally the designed state predictive controllers using LQ control with an observer are implemented and some simulation results obtained with SIMULINK and the ns‐2 simulator are presented. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 156(3): 41–47, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20405
The generation of thymus‐independent germinal centers depends on CD40 but not on CD154, the T cell‐derived CD40‐ligand
Authors: Gaspal Fabrina M. C. , McConnell Fiona M. , Kim Mi‐Yeon , Gray David , Kosco‐Vilbois Marie H. , Raykundalia Chandra R. , Botto Marina , Lane Peter J. L.
Published: June 2006

In this report, we show that the formation of germinal center (GC)‐like structures to thymus‐independent type 2 antigens in mice depends on intact signals through CD40, but does not depend on T cell‐derived CD40‐ligand (CD154). In addition, we show that follicular dendritic cells (FDC) are also critical to thymus‐independent GC formation, as their depletion by blockade of lymphotoxin‐β receptor signals abrogated GC development unless the responding B cells bound antigen with high affinity. Further evidence that immune complexes drove this CD40‐dependent B cell proliferation was provided by the observation that an antibody that detects immune complexes containing complement component 4 on FDC also inhibited thymus‐independent GC formation when injected in vivo at the time of immunization. Finally, we show that thymus‐independent B cell proliferation was associated with class switching to IgG3, as IgG3+ antigen‐specific switched B cells could be visualized directly in GC, suggesting that immune complexes can provide the signals for class switching within GC in the absence of CD154.
The role of Th2 cytokines, chemokines and parasite products in eosinophil recruitment to the gastrointestinal mucosa during helminth infection
Authors: Dixon Helen , Blanchard Carine , deSchoolmeester Matthew L. , Yuill Nicola C. , Christie Julie W. , Rothenberg Marc E. , Else Kathryn J.
Published: June 2006

Trichinella spiralis and Trichuris muris are nematode parasites of the mouse, dwelling in the small and large intestines, respectively: worm expulsion requires development of a Th2 immune response. The chemokine CCL11 is agonist for the chemokine receptor CCR3 and acts in synergy with IL‐5 to recruit eosinophils to inflammatory sites. The role of CCL11 in gastrointestinal helminth infection has not been previously studied. We challenged wild‐type (WT) BALB/c, CCL11 single knockout (SKO) and CCL11 IL‐5 double knockout (DKO) mice with either T. spiralis muscle larvae or T. muris eggs in order to examine eosinophil recruitment to the small and large intestine during helminth infection. A peripheral eosinophilia was seen in WT and SKO mice during T. spiralis infection but not with T. muris. Gastrointestinal eosinophilia was markedly reduced but not ablated in SKO mice ‐ and negligible in DKO mice ‐ infected with either nematode. The residual eosinophilia and up‐regulation of CCL24 mRNA in the gastrointestinal tract of SKO mice infected with either nematode, together with the presence of an eosinophil‐active factor in T. spiralis and T. muris products, suggest that CCL11 is the salient but not the sole eosinophil chemoattractant of biological significance during gastrointestinal helminth infection.
Inefficient processing of mRNA for the membraneform of IgE is a genetic mechanism to limit recruitment of IgE‐secreting cells
Authors: Karnowski Alexander , Achatz‐Straussberger Gertrude , Klockenbusch Cordula , Achatz Gernot , Lamers Marinus C.
Published: June 2006

Immunoglobulin E (IgE) is the key effector element in allergic diseases ranging from innocuous hay fever to life‐threatening anaphylactic shock. Compared to other Ig classes, IgE serum levels are very low. In its membrane‐bound form (mIgE), IgE behaves as a classical antigen receptor on B lymphocytes. Expression of mIgE is essential for subsequent recruitment of IgE‐secreting cells. We show that in activated, mIgE‐bearing B cells, mRNA for the membrane forms of both murine and human epsilon (ϵ) heavy chains (HC) are poorly expressed compared to mRNA for the secreted forms. In contrast, in mIgG‐bearing B cells, mRNA for the membrane forms of murine gamma‐1 (γ1) and the corresponding human γ4 HC are expressed at a much higher level than mRNA for the respective secreted forms. We show that these findings correlate with the presence of deviant polyadenylation signal hexamers in the 3′ untranslated region (UTR) of both murine and human ϵ genes, causing inefficient processing of primary transcripts and thus poor expression of the proteins and poor recruitment of IgE‐producing cells in the immune response. Thus, we have identified a genetic steering mechanism in the regulation of IgE synthesis that represents a further means to restrain potentially dangerous, high serum IgE levels.
You say ITAM and I say ITIM, let's call the whole thing off: the ambiguity of immunoreceptor signalling
Authors: Barrow Alexander David , Trowsdale John
Published: June 2006

Paradigms of protein tyrosine kinase (PTK)‐mediated immunoreceptor signalling have developed largely from studies of molecules containing immunoreceptor tyrosine‐based activation motifs (ITAM) and immunoreceptor tyrosine‐based inhibition motifs (ITIM). In some circumstances, ITAM can mediate inhibition and ITIM can propagate activation signals. In addition to classical immune cells, some ITAM‐ and ITIM‐encoding proteins are more widely expressed and are crucial to the development of haemopoietic cells, like osteoclasts and natural killer cells, as well as tissues such as bone and brain. Closer analysis of activating proteins reveals that some potentially encode ITIM within an ITAM. These ‘closet’ ITIM could, under conditions of partial ITAM phosphorylation, mediate inhibitory signalling.
Shaking table tests on a high‐rise RC building model having torsional eccentricity in soft lower storeys
Authors: Ko Dong‐Woo , Lee Han‐Seon
Published: June 2006

A series of shaking table tests on a 1:12‐scale model using scaled TaftN21E earthquake records were conducted to investigate the seismic performance of a 17‐storey high‐rise reinforced concrete structure with a high degree of torsional eccentricity and soft‐storey irregularities in the bottom two storeys. Based on the analysis of test results, the following conclusions were drawn: (1) the model responded mainly in the coupled mode of translation and torsion or in the torsional mode. Under severe table shaking, the flexible side underwent large inelastic deformation, and the predominant mode of the model changed from the coupled mode to the torsional mode, resulting in greatly increased torsional stiffness, thereby limiting damage in the flexible frame; (2) the shear force and deformation of the flexible side were governed by the torsional behaviour, whereas those of the stiff side were affected mainly by the overturning deformation. The lateral stiffness of the shear wall in the torsional mode was about four times that in the coupled mode because the warping deformation due to torsion counteracted the flexural deformation due to overturning moment in the torsional mode; and (3) the reversed cyclic overturning moments predicted by linear elastic dynamic analysis in the direction transverse to the table excitations contradicted unilateral overturning moments of the serviceability‐level test results, which showed a bias towards tension or compression in the columns. Copyright © 2006 John Wiley & Sons, Ltd.
The Dutch tariff: results and arguments for an effective design for national EQ‐5D valuation studies
Authors: Lamers L. M. , McDonnell J. , Stalmeier P. F. M. , Krabbe P. F. M. , Busschbach J. J. V.
Published: June 2006

The objective of this study was to estimate a Dutch EQ‐5D tariff and to determine in a simulation study using the dataset of the original UK valuation study, the number of health states and respondents needed to estimate a reliable tariff. In all, 300 Dutch respondents directly valued 17 states compared to 3000 respondents and 42 states in the original MVH protocol. The results reaffirmed differences in health‐related preferences between countries, justifying the estimation of national tariffs. The mean absolute error was 0.030. The design of this study is recommended for national EQ‐5D valuation studies. Copyright © 2006 John Wiley & Sons, Ltd.
Underage alcohol use, delinquency, and criminal activity
Authors: French Michael T. , Maclean Johanna C.
Published: June 2006

Since 1988, the minimum legal drinking age (MLDA) has been 21 years for all 50 US states. The increasing prevalence of teenagers driving under the influence (DUI) of alcohol and the resulting traffic accidents were two main reasons for raising the MLDA to 21 years. Following the passage of this legislation, several published studies have found that the higher MLDA is associated with a significant reduction in both fatal and non‐fatal accidents. While the relationship between MLDA and DUI events among young adults has been extensively studied, less information is available on other potential consequences of underage drinking. The present study uses data from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), a recent nationally representative survey, to investigate the effects of underage drinking on a variety of delinquency and criminal activity consequences. After controlling for the endogeneity of alcohol use where appropriate, we find strong evidence that various measures of alcohol consumption are related both to delinquency and to criminal activity. However, the findings are not uniform across gender as we find striking differences between males and females. These results have interesting policy and public health implications regarding underage drinking. Copyright © 2006 John Wiley & Sons, Ltd.
Dynamics in the use of drugs
Authors: van Ours Jan C.
Published: June 2006

This paper uses information about prime age individuals living in Amsterdam to study the dynamics in the use of tobacco, cannabis, and cocaine. The analysis examines transitions from non‐use to use, as well as transitions from use to non‐use. Particular attention is given to the effect of the age of onset on quitting behavior. The empirical analysis shows that for most of the drugs investigated, the earlier individuals start using a particular drug the less likely they are to stop using that drug. Copyright © 2006 John Wiley & Sons, Ltd.
DFT calculations of 57Fe Mössbauer isomer shifts and quadrupole splittings for iron complexes in polar dielectric media: Applications to methane monooxygenase and ribonucleotide reductase
Authors: Han Wen‐Ge , Liu Tiqing , Lovell Timothy , Noodleman Louis
Published: June 2006

To predict the isomer shifts of Fe complexes in different oxidation and spin states more accurately, we have performed linear regression between the measured isomer shifts (δexp) and DFT (PW91 potential with all‐electron triple‐ζ plus polarization basis sets) calculated electron densities at Fe nuclei [ρ(0)] for the Fe2+,2.5+ and Fe2.5+,3+,3.5+,4+ complexes separately. The geometries and electronic structures of all complexes in the training sets are optimized within the conductor like screening (COSMO) solvation model. Based on the linear correlation equation δexp = α[ρ(0) − 11884.0] + C, the best fitting for 17 Fe2+,2.5+ complexes (totally 31 Fe sites) yields α = −0.405 ± 0.042 and C = 0.735 ± 0.047 mm s−1. The correlation coefficient is r = −0.876 with a standard deviation of SD = 0.075 mm s−1. In contrast, the linear fitting for 19 Fe2.5+,3+,3.5+,4+ complexes (totally 30 Fe sites) yields α = −0.393 ± 0.030 and C = 0.435 ± 0.014 mm s−1, with the correlation coefficient r = −0.929 and a standard deviation SD = 0.077 mm s−1. We provide a physical rationale for separating the Fe2+,2.5+ fit from the Fe2.5+,3+,3.5+,4+ fit, which also is clearly justified on a statistical empirical basis. Quadrupole splittings have also been calculated for these systems. The correlation between the calculated (ΔEQ(cal)) and experimental (ΔEQ(exp)) quadrupole splittings based on |ΔEQ(exp)| = A |ΔEQ(cal)| + B yields slope A, which is almost the ideal value 1.0 (A = 1.002 ± 0.030) and intercept B almost zero (B = 0.033 ± 0.068 mm s−1). Further calculations on the reduced diferrous and oxidized diferric active sites of class‐I ribonucleotide reductase (RNR) and the hydroxylase component of methane monooxygenase (MMOH), and on a mixed‐valent [(tpb)Fe3+(μ‐O)(μ‐CH3CO2)Fe4+(Me3[9]aneN3)]2+ (S = 3/2) complex and its corresponding diferric state have been performed. Calculated results are in very good agreement with the experimental data. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 1292–1306, 2006
DFT models for copper(II) bispidine complexes: Structures, stabilities, isomerism, spin distribution, and spectroscopy
Authors: Atanasov Mihail , Comba Peter , Martin Bodo , Müller Vera , Rajaraman Gopalan , Rohwer Heidi , Wunderlich Steffen
Published: June 2006

Various DFT and ab initio methods, including B3LYP, HF, SORCI, and LF‐density functional theory (DFT), are used to compute the structures, relative stabilities, spin density distributions, and spectroscopic properties (electronic and EPR) of the two possible isomers of the copper(II) complexes with derivatives of a rigid tetradentate bispidine ligand with two pyridine and two tertiary amine donors, and a chloride ion. The description of the bonding (covalency of the copper–ligand interactions) and the distribution of the unpaired electron strongly depend on the DFT functional used, specifically on the nonlocal DF correlation and the HF exchange. Various methods may be used to optimize the DFT method. Unfortunately, it appears that there is no general method for the accurate computation of copper(II) complexes, and the choice of method depends on the type of ligands and the structural type of the chromophore. Also, it appears that the choice of method strongly depends on the problem to be solved. LF‐DFT and spectroscopically oriented CI methods (SORCI), provided a large enough reference space is chosen, yield accurate spectroscopic parameters; EDA may lead to a good understanding of relative stabilities; accurate spin density distributions are obtained by modification of the nuclear charge on copper; solvation models are needed for the accurate prediction of isomer distributions. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 1263–1277, 2006
Exploring the cell's network with molecular imaging
Authors: Enzmann Dieter R.
Published: June 2006

Molecular imaging is already a powerful tool for investigating molecular interactions within the cell. Interpreting molecular imaging findings will, however, take us into the more unfamiliar, nonlinear realm of networks. The network class of interest is the “scale‐free” network, which characterizes not only the cell, but also surprisingly, other real work networks such as the world wide web. This network topology yields insights in how the cell is functionally organized via motifs, modules, and different types of hubs. Additional organizational information is gained from the cell's evolutionary history. Interpretation of molecular images will be deepened by a both qualitative and quantitative knowledge of the cell's network. Importantly, cell network behavior can be independent of molecular detail. For this reason, the same molecule can serve different functions in different cells or even within the same cell. Since a scale‐free network's behavior is likely to be nonlinear and exhibit emergent behavior, a degree of caution is prudent in assigning cause and effect to molecular imaging findings in our effort to reengineer some of the cell's functions. Molecular imagers will need to be cognizant of the level of organization in the cell's network they are interrogating. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Bone metastases from head and neck paragangliomas: Uncommon MR findings in an uncommon condition—Report of three cases
Authors: Duet Michèle , Herman Philippe , Wassef Michel , Huy Patrice Tran Ba , Laredo Jean‐Denis
Published: June 2006

Malignancy (defined as metastatic disease) has been reported in nearly 5% of head and neck paragangliomas. Metastases preferentially target the lymph nodes, lung, liver, or bone. We describe three patients with multiple silent bone metastases exhibiting a fatty halo at MRI that coexisted with expansive bone lesions. In all cases, 123I‐metaiodobenzylguanidine (123MIBG) scintigraphy showed no abnormal tracer uptake, whereas 111In‐pentetreotide scintigraphy visualized a few silent bone metastases. These findings indicate that MRI should be included in the staging of paraganglioma patients with risk factors for malignancy. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Comparison of schwann cell and sciatic nerve transcriptomes indicates that mouse is a valid model for the human peripheral nervous system
Authors: Ten Asbroek Anneloor L.M.A. , Van Ruissen Fred , Ruijter Jan M. , Baas Frank
Published: June 2006

High‐throughput gene expression analyses of murine models of the peripheral nervous system (PNS), and its cellular components, have yielded enormous amounts of expression data of the PNS in various conditions. These data provided clues for future research directions to further decipher this complex organ in relation to acquired and inherited PNS diseases. Various studies addressing the validity of mouse models for human conditions in other tissues and cell types have indicated that in many cases the mouse model only poorly represents the human situation. To determine how well the mouse can serve as model to study the biological processes occurring in the PNS, we compared the gene expression profiles that we generated for mouse and human sciatic nerve and cultured Schwann cells derived thereof. A two‐way analysis based on the differentially expressed genes between the sciatic nerve and the cultured Schwann cell, and which takes into account the differential expression between mouse and man, indicates that the human PNS is well represented by that of the mouse in terms of the “biological processes” ontology. © 2006 Wiley‐Liss, Inc.
Synthesis of Polyanilines Bearing Optically Active Substituents
Authors: Goto Hiromasa
Published: June 2006

Summary: Optically active polyanilines were prepared by an interfacial polymerization with (NH4)2S2O8 in a water/perchloric acid/chloroform system. The pristine polymer obtained in this way is in the oxidized (doped) form. The polymers display the mirror‐image Cotton effect. The doping process in solution allows a change in the circular dichroism of the polymer. The procedure has great potential in the improved preparation of durable optoelectrical devices based on the good film‐forming properties of chiral polymers.

CD spectra of R‐P2 (solid line) and S‐P2 (dashed line) in 4.0 × 10−4 M THF solution.

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CD spectra of R‐P2 (solid line) and S‐P2 (dashed line) in 4.0 × 10−4 M THF solution.
Azoalkanes: A Novel Class of Flame Retardants
Authors: Nicolas Ronan C. , Wilén Carl‐Eric , Roth Michael , Pfaendner Rudolf , King Roswell E.
Published: June 2006

Summary: The synthesis of azoalkanes such as azocyclohexane (1) and 4,4′‐bis(cyclohexylazocyclohexyl)methane (2) and their use as flame retardants in polymeric substrates is reported. For the first time it is demonstrated that azoalkanes alone can effectively provide flame retardancy and self‐extinguishing properties to poly(propylene) films at a very low concentration of 0.25 to 0.5 wt.‐%. All the poly(propylene) formulations passed DIN 4102‐1/B2 standards and the instant azoalkane‐containing poly(propylene) blends show no discoloration.

4,4′‐bis(cyclohexylazocyclohexyl)methane.

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4,4′‐bis(cyclohexylazocyclohexyl)methane.
Homogeneously Dispersed Poly(propylene)/SiO2 Nanocomposites with Unprecedented Transparency
Authors: Asuka Kazuo , Liu Boping , Terano Minoru , Nitta Koh‐hei
Published: June 2006

Summary: Physico‐chemical interactions between hydrophobic polyolefin materials and hydrophilic inorganic nanoparticles such as surface‐hydroxylated SiO2 have not been well understood so far. In this study, the effects of particle size and content of SiO2 nanoparticles on isothermal growth rate of PP spherulites in various PP/SiO2 nanocomposites were investigated by polarized optical microscopy. It was unexpected to find that hydrophilic SiO2 nanoparticles can be homogeneously dispersed in a PP matrix. Spherulite growth rates of PP in PP/SiO2 nanocomposites decrease significantly with increasing SiO2 content and decreasing particle size. Most interestingly, the spherulite growth rate was zero for PP/16 nm‐SiO2 nanocomposites with SiO2 content above 2.5 wt.‐% resulting in a highly transparent film.

Photographs of 200 µm‐thick PP and PP/16 nm‐SiO2 (5 wt.‐%) sheets in front of a graphic pattern.

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Photographs of 200 µm‐thick PP and PP/16 nm‐SiO2 (5 wt.‐%) sheets in front of a graphic pattern.
The adaptive value of personality differences revealed by small island population dynamics
Authors: Camperio Ciani Andrea S. , Capiluppi Claudio , Veronese Antonio , Sartori Giuseppe
Published: June 2006

Whether differences in personality among populations really exist and, if so, whether they are only due to cultural and linguistic differences or have a genetically selected adaptive value, is a controversial issue. In this research, we compared three Italian populations living on three small archipelagos in the Tyrrhenian Sea (n = 993), with their corresponding neighbouring mainlanders (n = 598), i.e. sharing the same geographical origin, culture and language. We used an adjective‐based Big Five questionnaire in order to measure personality traits in four categories of individuals for each archipelago/mainland population: (1) original islanders; (2) non‐original islanders; (3) mainlanders and (4) immigrants to the islands. We further analysed original and non‐original islanders who had or had not emigrated from the islands. We found that islanders had different personality traits from mainlanders, the former being more conscientious and emotionally stable and less extraverted and open to experience. We also found that the subgroup of islanders whose ancestors had inhabited their island for about 20 generations in isolation (original islanders, n = 624) were less extraverted and open to experience than immigrants (n = 193). In contrast, immigrants retained the typical personality profile of the mainland populations. Lastly, emigrants from the islands (n = 209) were significantly more extraverted and open to experience than original and non‐original islanders who had never left their island (n = 741). We hypothesise that population differences in extraversion and openness to experience are more probably related to genetic differences which evolved rapidly, presumably through an active gene flow produced by selective emigration from the islands. Copyright © 2006 John Wiley & Sons, Ltd.
Regulatory mode and the joys of doing: effects of ‘locomotion’ and ‘assessment’ on intrinsic and extrinsic task‐motivation
Authors: Pierro Antonio , Kruglanski Arie W. , Higgins E. Tory
Published: June 2006

This research investigates the relation between regulatory‐mode (Higgins, Kruglanski, & Pierro, 2003; Kruglanski et al., 2000) and task motivation. Four studies conducted in diverse field and laboratory settings support the notions that ‘locomotion’, i.e. a self‐regulatory emphasis on movement from state to state, is positively related to intrinsic task motivation, whereas ‘assessment’, i.e. a self‐regulatory tendency to emphasize comparative appraisal of entities and states (such as goals and means) is positively related to extrinsic motivation. It is further found that ‘locomotion’, but not ‘assessment’, is positively related to effort investment, which, in turn, is positively related to goal attainment. Attainment is, additionally, predicted by an interaction of locomotion and assessment, such that individuals are most likely to reach their goals if they are high on both these dimensions. Taken as a body, these findings highlight the relevance of regulatory‐mode concepts to the study of task motivation and activity experience. Copyright © 2006 John Wiley & Sons, Ltd.
Preparation and properties of chitosan/poly(vinyl alcohol) blend foams for copper adsorption
Authors: Wang Xiao , Chung Yong Sik , Lyoo Won Seok , Min Byung Gil
Published: June 2006

A new form of polymer blend, macroporous chitosan/poly(vinyl alcohol) (PVA) foams made by a starch expansion process, exhibits the functionalities of chitosan while avoiding its poor mechanical properties and chemical instabilities. The appropriate conditions for foaming are discussed using both insoluble and water‐soluble chitosan. The chitosan/PVA foams demonstrated interconnected and open‐cell structures with large pore size from tens to hundreds of micrometers and high porosities from 73.6 to 84.3%. Glutaraldehyde was employed to improve the retention of chitosan and copper adsorption of the chitosan/PVA foams. While it increased the retention of chitosan and the adsorption capacities, glutaraldehyde decreased the pore size and porosity. The macroporous structure of the chitosan/PVA foams indicates extensive application prospects in terms of the considerable adsorption of heavy metal ions. Copyright © 2006 Society of Chemical Industry
Synthesis and properties of bismaleimide resin containing dicyclopentadiene or dipentene. VI
Authors: Hwang Hann‐Jang , Li Chun‐Hung , Wang Chun‐Shan
Published: June 2006

New aromatic bismaleimides (BMIs), bis(4‐maleimidophenoxy‐3,5‐dimethylphenyl)dicyclopentadiene (DCPDBMI) and bis(4‐maleimido‐phenoxy‐3,5‐dimethylphenyl)dipentene (DPBMI), containing a large dicyclopentadiene (DCPD) or dipentene (DP) and aryl ether linkage, were synthesized from diamine bis(4‐aminophenoxy‐3,5‐dimethylphenyl)dicyclopentadiene (DCPDA) or bis(4‐aminophenoxy‐3,5‐dimethylphenyl)dipentene(DPA) and maleic anhydride by the usual two‐step procedure that included ring‐opening addition to give bismaleamic acid, followed by cyclodehydration to bismaleimide. The monomers were characterized by Fourier transform infrared spectroscopy, proton NMR, elemental analyses, and mass spectra. Their thermal polymerization was investigated by DSC. The presence of a large cycloaliphatic moiety in the backbone of the bismaleimide increased the curing temperature and reduced the reactivity of the maleimide bond. Thermal and electrical properties of cured bismaleimide resins were studied using a dielectric analyzer, dynamic mechanical analyzer, and thermal gravimetric analyzer. These data were compared with that of commercial 4,4‐bismaleimidodiphenylmethane (DDMBMI). The cured DCPDBMI or DPBMI exhibits a lower dielectric constant, dissipation factor and moisture absorption than those of DDMBMI. Copyright © 2006 Society of Chemical Industry
Proteomic biomarkers for autoimmune disease
Authors: Hueber Wolfgang , Robinson William H.
Published: June 2006

Autoimmune diseases affect 3% of the world population, yet the diagnosis and classification of autoimmune diseases remain based on clinical examination combined with traditional laboratory tests and imaging studies. The development of genomic and proteomic technologies provides an unprecedented ability to identify novel biosignatures to diagnose, classify, and guide therapeutic decision making in patients with autoimmune disease. In this article, we review recent advances in proteomics technologies and their application to autoimmune disease.
Old fold in a new X‐ray diffraction dataset? Low‐resolution molecular replacement using representative structural templates can provide phase information
Authors: Rajavel M. , Warrier Thulasi , Gopal B.
Published: June 2006

The advent of structural genomics has led to a dramatic increase in the number of structures deposited in the Protein Data Bank. The number of new folds, however, still remains a very small fraction of the total number of deposited structures. Recent data on the progress of the structural genomics initiative reveals that more than 85% of target proteins that progress to the stage of data collection and structure determination have a known fold. Enzymes, which tend to exploit reaction space while adopting a common stable scaffold, contribute significantly to this observation. Herein, we evaluate a method to examine the “old fold in a new dataset” scenario likely to be encountered in the structural genomics pipeline. We demonstrate that a fold detection strategy based on secondary structure signatures followed by molecular replacement using a minimalist model can be effectively used to solve the phase problem in X‐ray crystallography without further recourse to heavy atom derivatives or multiple anomalous dispersion techniques. Three common folds—the triosephosphate isomerase (TIM), adenine nucleotide alpha hydrolase‐like (HUP), and RNA recognition motif (RRM)—were examined using this approach. The results presented herein also provide an estimate of the extent of phase information that can be derived from a single domain in a large multidomain structure. Proteins 2006. © 2006 Wiley‐Liss, Inc.
Molecular simulations reveal a new entry site in quercetin 2,3‐dioxygenase. A pathway for dioxygen?
Authors: Fiorucci Sébastien , Golebiowski Jérôme , Cabrol‐Bass Daniel , Antonczak Serge
Published: June 2006

Molecular dynamics simulations performed on quercetin 2,3‐dioxygenase have shown the existence of a channel linking the bulk solvent and the cavity of the enzyme. Although much is known about the the oxygenolysis reaction catalyzed by this enzyme, the way dioxygen enters the active site has not been firmly established. The size, orientation and hydrophobic character of this channel suggests that it could provide an entrance for molecular dioxygen into the cavity. Free energy calculations show that such a process is likely to occur. Proteins 2006. © 2006 Wiley‐Liss, Inc.
STRUCTFAST: Protein sequence remote homology detection and alignment using novel dynamic programming and profile–profile scoring
Authors: Debe Derek A. , Danzer Joseph F. , Goddard William A. , Poleksic Aleksandar
Published: June 2006

STRUCTFAST is a novel profile—profile alignment algorithm capable of detecting weak similarities between protein sequences. The increased sensitivity and accuracy of the STRUCTFAST method are achieved through several unique features. First, the algorithm utilizes a novel dynamic programming engine capable of incorporating important information from a structural family directly into the alignment process. Second, the algorithm employs a rigorous analytical formula for profile–profile scoring to overcome the limitations of ad hoc scoring functions that require adjustable parameter training. Third, the algorithm employs Convergent Island Statistics (CIS) to compute the statistical significance of alignment scores independently for each pair of sequences. STRUCTFAST routinely produces alignments that meet or exceed the quality obtained by an expert human homology modeler, as evidenced by its performance in the latest CAFASP4 and CASP6 blind prediction benchmark experiments. Proteins 2006. © 2006 Wiley‐Liss, Inc.
Variability of pesticide residues in crop units
Authors: Ámbrus Árpád
Published: June 2006

The results of 89 new field trials and 11 supervised trials were considered, together with 91 sets of residue data evaluated earlier. The datasets consisted of 22 643 valid residue data. As all variability factors calculated from individual sample sets are affected by the uncertainties of sampling and analysis, the average of the P0.975/Rave (97.5th percentile of the residue population divided by the average residues in the lot) values gives the best estimate for the variability factor. The Harrell–Davis (H–D) method gave an average value of 2.89 for the variability factor for all samples, while the average variability factors obtained from samples derived from the new field and supervised trials were 2.8 and 2.7 with the IUPAC and H–D methods respectively. The number of residue values below the LOQ in a sample set significantly affects the observed variability factors. It was found that datasets containing over 20% non‐quantifiable residues might not reflect the true variability of the residues. Mixing of treated and non‐treated commodities may significantly increase the apparent variability. Consequently, only datasets of known origin and consisting of well‐quantifiable residues should be used for estimation of the variability factor. Samples taken from marketed lots may not represent a single lot, and thus they have limited value in estimating the variability factor. The large number of residue data confirms the applicability of the default variability factor of 3 adopted by the FAO/WHO for deterministic estimation of the acute intake of pesticide residues. Copyright © 2006 Society of Chemical Industry
Leaf surface characteristics of apple seedlings, bean seedlings and kohlrabi plants and their impact on the retention and rainfastness of mancozeb
Authors: Hunsche Mauricio , Bringe Katja , Schmitz‐Eiberger Michaela , Noga Georg
Published: June 2006

A study was made of the influence of the upper leaf surface characteristics on the retention and rainfastness of the contact fungicide mancozeb with and without tank‐mix adjuvants (RSO 5 and RSO 60) on apple seedlings, bean seedlings and kohlrabi plants. Large differences in roughness, in the amount and composition of surface waxes and in the retention and rainfastness of mancozeb were found among species. Strong correlations between roughness and total amount of surface waxes and mass of C29 alkane in the wax mass were also found. Fungicide retention was strongly, negatively correlated with surface roughness, total epicuticular wax, amount of C29 alkane and the total mass of alkanes. Rainfastness correlated strongly or very strongly with the amount of C28 alcohol and C33 alkane. The addition of a more hydrophobic (RSO 5) or a more hydrophilic (RSO 60) adjuvant to the spray solution influenced retention and rainfastness, and also altered the correlation coefficients. The present results support earlier observations which show that the success of adjuvants in enhancing the retention and rainfastness of agrochemicals depends on the characteristics of the leaf surface. Copyright © 2006 Society of Chemical Industry
A route comprehension support system for a robotic travel aid
Authors: Shi Yafang , Kotani Shinji , Mori Hideo
Published: June 2006

We have developed a robotic travel aid that can provide assistance to guide visually impaired people. According to the opinions of visually impaired people, for such travel aids to be safe and easy to use, the person being guided must be able to comprehend their route from the point of departure to their destination before starting off on their journey. Therefore, we have developed a route comprehension support system to be used as a subsystem in such a robotic travel aid. This system generates an explanation of the route that will be taken by the user on the basis of an XML file containing route information. In addition, we have designed an interface that takes into consideration the user's disabilities by using a combination of a touch keypad and speech synthesis. The system is able to make use of the fully functioning senses of the user to acquire information regarding the environment through which the user is passing, for instance, the user's sense of distance and information regarding how they control the robot, and generates route guidance instructions including information regarding footpaths, traffic controls, and the shape and size of intersections that can be confirmed by the user. We have verified the effectiveness of this guide system by means of experiments to evaluate the route understanding system with seven visually impaired subjects and experiments to evaluate the guidance performance of the system with four subjects; in both cases the system receiving positive evaluations. © 2006 Wiley Periodicals, Inc. Syst Comp Jpn, 37(9): 87–99, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10568
An algorithm for the extraction of pulmonary fissures from low‐dose multislice CT image
Authors: Saita Shinsuke , Kubo Mitsuru , Kawata Yoshiki , Niki Noboru , Ohmatsu Hironobu , Moriyama Noriyuki
Published: June 2006

With the recent development of multislice CT, it is now possible to derive 3D cross‐sectional images for the whole lung region with high accuracy in a short time. In particular, with the drastic improvement of resolution in the axial direction, it is expected that 3D image analysis will play a significant role. This paper discusses an algorithm that extracts the pulmonary fissures from multislice CT images. The fissure is a feature which is clinically important for the identification of lung sections. The fissures have a very thin film structure. The proposed method extracts the lung fissure by identification of the region containing the fissure and emphasis of the fissure. The lung blood vessels are classified for each lobe, and the region containing the fissure is identified on the basis of the 3D distance from the lung blood vessel. Then, region growing is applied on the basis of the normal vector of the emphasized sheet shadow, and the fissure is extracted. The proposed method is applied to clinical images of 20 cases, and its accuracy is evaluated, demonstrating the effectiveness of the method. © 2006 Wiley Periodicals, Inc. Syst Comp Jpn, 37(9): 63–76, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.20167