bluuebunny/crossref_metadata_2025 huggingface dataset:
DNA methylation 40 years later: Its role in human health and disease
Authors: Scarano Maria Irene , Strazzullo Maria , Matarazzo Maria Rosaria , D'Esposito Maurizio
Published: January 2005

A long path, initiated more than 40 years ago, has led to a deeper understanding of the complexity of gene regulation in eukaryotic genomes. In addition to genetic mechanisms, the imbalance in the epigenetic control of gene expression may profoundly alter the finely tuned machinery leading to gene regulation. Here, we review the impact of the studies on DNA methylation, the “primadonna” in the epigenetic scenario, on the understanding of basic phenomena, such as X inactivation and genomic imprinting. The effect of deregulation of DNA methylation on human health, will be also discussed. Finally, an attempt to predict future directions of this rapidly evolving field has been proposed, with the certainty that, fortunately, science is always better than predictions. © 2005 Wiley‐Liss, Inc.
miR‐15a and miR‐16‐1 down‐regulation in pituitary adenomas
Authors: Bottoni Arianna , Piccin Daniela , Tagliati Federico , Luchin Andrea , Zatelli Maria Chiara , Degli Uberti Ettore C.
Published: January 2005

Micro RNAs (miRs) are small noncoding RNAs, functioning as antisense regulators of other RNAs. miR‐15a and miR‐16‐1 genes are located at chromosome 13q14, a region which is frequently deleted in pituitary tumors. An inverse correlation has been shown in B cell chronic lymphocytic leukemia (B‐CLL) between miR‐15a and miR‐16‐1 expression and the expression levels of arginyl‐tRNA synthetase (RARS), an enzyme which associates with the cofactor p43 in the aminoacyl‐tRNA synthetase complex. When secreted, p43 regulates local inflammatory response and macrophage chemotaxis, and seems to have anti‐neoplastic properties in mice. We explored miR‐15a and miR‐16‐1 expression in 10 GH‐secreting and in 10 PRL‐secreting pituitary macroadenomas by Northern blot, and investigated the possible correlation with in vivo and in vitro characteristics. We found that miR‐15a and miR‐16‐1 are expressed at lower levels in pituitary adenomas as compared to normal pituitary tissue. Moreover, their expression inversely correlates with tumor diameter and with RARS expression (P < 0.05), but directly correlates with p43 secretion (P < 0.02). Therefore, miR15 and miR16 down‐regulation in pituitary adenomas correlates with a greater tumor diameter and a lower p43 secretion, suggesting that these genes may, at least in part, influence tumor growth. © 2005 Wiley‐Liss, Inc.
Porphyromonas gingivalis lipopolysaccharide induces shedding of syndecan‐1 expressed by gingival epithelial cells
Authors: Andrian Elisoa , Grenier Daniel , Rouabhia Mahmoud
Published: January 2005

Syndecans are constitutively shed from growing epithelial cells as the part of normal cell surface turnover. However, increased serum levels of the soluble syndecan ectodomain have been reported to occur during bacterial infections. The aim of this study was to evaluate the potential of lipopolysaccharide (LPS) from the periodontopathogen Porphyromonas gingivalis to induce the shedding of syndecan‐1 expressed by human gingival epithelial cells. We showed that the syndecan‐1 ectodomain is constitutively shed from the cell surface of human gingival epithelial cells. This constitutive shedding corresponding to the basal level of soluble syndecan‐1 ectodomain was significantly increased when cells were stimulated with P. gingivalis LPS and reached a level comparable to that caused by phorbol myristic acid (PMA), an activator of protein kinase C (PKC) which is well known as a shedding agonist. The syndecan‐1 shedding was paralleled by pro‐inflammatory cytokine interleukin‐1 beta (IL‐1β), IL‐6, IL‐8, and tumor necrosis factor alpha (TNF‐α) release. Indeed, secretion of IL‐1β and TNF‐α increased following stimulation by P. gingivalis LPS and PMA, respectively. When recombinant forms of these proteins were added to the cell culture, they induced a concentration‐dependent increase in syndecan‐1 ectodomain shedding. A treatment with IL‐1β converting enzyme (ICE) specific inhibitor prevented IL‐1β secretion by epithelial cells stimulated by P. gingivalis LPS and decreased the levels of shed syndecan‐1 ectodomain. We also observed that PMA and TNF‐α stimulated matrix metalloproteinase‐9 secretion, whereas IL‐1β and P. gingivalis LPS did not. Our results demonstrated that P. gingivalis LPS stimulated syndecan‐1 shedding, a phenomenon that may be mediated in part by IL‐1β, leading to an activation of intracellular signaling pathways different from those involved in PMA stimulation. © 2005 Wiley‐Liss, Inc.
Asymmetric graph coloring games
Authors: Kierstead H. A.
Published: January 2005

We introduce the (a,b)‐coloring game, an asymmetric version of the coloring game played by two players Alice and Bob on a finite graph, which differs from the standard version in that, in each turn, Alice colors a vertices and Bob colors b vertices. We also introduce a related game, the (a,b)‐marking game. We analyze these games and determine the (a,b)‐chromatic numbers and (a,b)‐coloring numbers for the class of forests and all values of a and b. © 2005 Wiley Periodicals, Inc. J Graph Theory 48: 169–185, 2005
Circular choosability of graphs
Authors: Zhu Xuding
Published: January 2005

This paper discusses the circular version of list coloring of graphs. We give two definitions of the circular list chromatic number (or circular choosability) χc, l(G) of a graph G and prove that they are equivalent. Then we prove that for any graph G, χc, l(G) ≥ χl(G) − 1. Examples are given to show that this bound is sharp in the sense that for any ϵ 0, there is a graph G with χc, l(G) > χl(G) − 1 + ϵ. It is also proved that k‐degenerate graphs G have χc, l(G) ≤ 2k. This bound is also sharp: for each ϵ < 0, there is a k‐degenerate graph G with χc, l(G) ≥ 2k − ϵ. This shows that χc, l(G) could be arbitrarily larger than χl(G). Finally we prove that if G has maximum degree k, then χc, l(G) ≤ k + 1. © 2005 Wiley Periodicals, Inc. J Graph Theory 48: 210–218, 2005
Synthesis of Block Copolymers containing Chain‐Controlled Aramid and Fluoroethylene Segments
Authors: Korematsu Arata , Furuzono Tsutomu , Kishida Akio
Published: January 2005

Summary: Novel block copolymers containing aromatic polyamide (aramid) and fluoroethylene segments were synthesized by a two‐step solution polycondensation. This synthetic method could control the chain‐length of aramid segments and these copolymers could have high structural regularity. The number‐average molecular weight ($\overline M _{\rm n}$) of one of these polymers is over 2.0 × 104. Incorporating fluoroethylene segments improves the solubility of the resulting polymer compared with conventional aramids.

The synthesis of the fluoroethylene‐aramid block copolymers.

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The synthesis of the fluoroethylene‐aramid block copolymers.
Amygdalar and hippocampal MRI volumetric reductions in Parkinson's disease with dementia
Authors: Junqué Carme , Ramírez‐Ruiz Blanca , Tolosa Eduardo , Summerfield Christopher , Martí María‐José , Pastor Pau , Gómez‐Ansón Beatriz , Mercader José Ma.
Published: January 2005

Parkinson's disease (PD) involves neuropathological changes in the limbic system that lead to neuronal loss and volumetric reductions of several nuclei. We investigated possible volumetric reductions of the amygdala and hippocampus associated to PD. We carried out magnetic resonance imaging (MRI) volumetric studies in 16 patients with PD and dementia (PDD), 16 patients with PD without dementia (PD), and 16 healthy subjects. The general analysis of variance (ANOVA) showed a significant group effect (for the amygdala, P = 0.01; for the hippocampus, P = 0.005). A post‐hoc test demonstrated that the differences were due to PDD and control group comparisons for the amygdala (P = 0.008) and for the hippocampus (P = 0.004). In nondemented PD subjects, we observed an 11% reduction in the amygdala and a 10% reduction in the hippocampus compared with that in controls. In summary, demented PD patients have clear amygdalar and hippocampal atrophy that remains statistically significant after controlling for global cerebral atrophy. Nondemented PD patients also showed a degree of volumetric reduction in these structures although the differences were not statistically significant. © 2005 Movement Disorder Society
GABAergic interneurons in human subthalamic nucleus
Authors: Lévesque Julie‐Christine , Parent André
Published: January 2005

The subthalamic nucleus (STN) is considered a homogeneous structure composed essentially of projection neurons that exert a profound glutamate‐mediated excitatory influence upon the main output structures of the basal ganglia. It is currently the most efficient target for deep brain stimulations designed to alleviate symptoms of Parkinson's disease. STN neurons were analyzed by applying stereological methods and single/double‐immunostaining procedures to postmortem material obtained from normal individuals. Besides a multitude of closely packed projection neurons (∼24.7 μm in diameter), the human STN (mean volume, 174.5 ± 20.4 mm3; total neuronal density, 239.5 ± 31.9 × 103) contained smaller neurons (∼12.2 μm), which displayed glutamic acid decarboxylase (GAD)65/67 immunoreactivity and shared the morphological features of interneurons described in Golgi studies of primate STN. These putative γ‐aminobutyric acid (GABA)ergic interneurons accounted for 7.5% of the total neuronal population of the STN. Although present throughout the nucleus, they were significantly more numerous in its posterior‐ventral‐medial sector, which belongs to the limbic/associative functional territory. Many projection neurons located dorsolaterally in the STN showed parvalbumin immunoreactivity and others lying ventromedially displayed calretinin immunostaining, but none of the GAD‐positive interneurons expressed these calcium‐binding proteins. Although less abundant than projection neurons, GABAergic interneurons might play a important role in the intrinsic organization of the STN. The morphological and chemical heterogeneity of the human STN reported here might have important implications in the functional organization of the basal ganglia. © 2005 Movement Disorder Society
Falls in degenerative cerebellar ataxias
Authors: van de Warrenburg Bart P.C. , Steijns Janneke A.G. , Munneke Marten , Kremer Berry P.H. , Bloem Bastiaan R.
Published: January 2005

We retrospectively and prospectively assessed the frequency and characteristics of falls in patients with degenerative cerebellar ataxias. The results show that falls occur very frequently in patients with degenerative cerebellar ataxias and that these falls are serious and often lead to injuries or a fear of falling. Clinicians should be aware of this problem in ataxia patients and should try to prevent falls. © 2005 Movement Disorder Society
Effect of titania nanoparticles on the morphology of low density polyethylene
Authors: Ma Dongling , Akpalu Yvonne. A. , Li Ying , Siegel Richard W. , Schadler Linda S.
Published: January 2005

The role of TiO2 nanoparticle surfaces in affecting the crystalline structure of low‐density polyethylene (LDPE) has been investigated by varying the nanoparticle surface from hydrophilic (as‐received) to less hydrophilic (dried) or more hydrophilic (polar silane treated). Differential scanning calorimetry (DSC) and wide‐angle X‐ray diffraction (WXRD) were used to determine the degree of crystallinity and crystalline structure. The impact of nanoparticle aggregates on the nanometer to micrometer organization of LDPE crystals was studied with atomic force microscopy (AFM) and small‐angle light scattering (SALS). This characterization showed that the presence of the TiO2 nanoparticles, with the various different surface conditions investigated, did not alter the degree of LDPE crystallinity, the unit cell dimensions, the average lamellar thickness, or the average spherulite size. However, the nanoparticles did affect the internal arrangement of intraspherulitic crystalline aggregates by decreasing the relative optic axis orientation of these crystals, usually referred to as internal spherulite disorder. The LDPE filled with the nanoparticles treated with a polar silane (N‐(2‐aminoethyl) 3‐aminopropyl‐trimethoxysilane (AEAPS)) showed the highest internal spherulitic disorder and exhibited the most poorly developed spherulite structure. The combination of SALS with AFM has allowed a detailed characterization of the morphology of the semicrystalline polymer nanocomposites. Information on the internal organization of the spherulites, the size of the nanoparticle aggregates, and the location of the nanoparticle aggregates can be uniquely obtained when both techniques are used. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 488–497, 2005
Investigation of the dynamics of poly(ether sulfone) membrane formation by immersion precipitation
Authors: Li Zhansheng , Jiang Chengzhang
Published: January 2005

Cast‐leaching experiments were carried out to investigate the dynamics of membrane formation by immersion precipitation, with an emphasis on the outflow of the solvent from casting solutions during the phase‐separation process. The casting solutions, consisting of poly(ether sulfone) as the polymer, N‐methyl‐2‐pyrolidone as the solvent, and water (H2O), isopropyl alcohol, 1‐butanol, and diethylene glycol as nonsolvent additives (NSAs), were immersed in a coagulation bath. Two thermodynamically vastly different coagulantsH2O, a strong coagulant, and ethylene glycol, a weak coagulant—were used to study the effect of the coagulant on the dynamics of membrane formation. The results showed that the outflow of the solvent during the initial stage of membrane formation was controlled by Fickian diffusion within the extremely wide range of conditions studied, that is, polymer concentrations of 10–38%, approaching ratios of 0–0.95, and thermodynamically vastly different NSAs and coagulants. The role of the initial state of the membrane‐forming solution, especially the conformational state of macromolecules in the membrane‐forming process, was examined. In contrast to those works on the behavior of small molecules, an attempt was made to qualitatively interpret membrane formation from the viewpoint of macromolecules. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 498–510, 2005
High Curie temperature Pb(Fe1/2Nb1/2)O3‐based ferroelectrics: 0.40Pb(Fe1/2Nb1/2)O3–0.34PbZrO3–0.26PbTiO3
Authors: Fang Bijun , Shan Yuejin , Tezuka Keitaro , Imoto Hideo
Published: January 2005

High‐Tm (∼270 °C) relaxor ferroelectrics 0.40Pb(Fe1/2Nb1/2)O3–0.34PbZrO3–0.26PbTiO3 (PFN40‐PZ34‐PT26) with pure perovskite phase were synthesized using conventional ceramic processing via a B‐site oxide mixing route for applications in high‐temperature high‐power‐density electrotransducers and high‐temperature capacitors. The relaxor behavior is confirmed by studying the frequency and temperature dependence of the dielectric response and polarization relaxation. The ceramics exhibit a large room‐temperature dielectric constant of ∼1540 and the dielectric constant is nearly independent of frequency with a temperature gradient of ∂ε/∂T = 5.2/°C in the low‐temperature region 250 K < T < 400 K. A strong frequency dependency and abnormal increase of dielectric constant are observed at temperatures around and below Tm, which is considered to be correlated with the phase transition from tetragonal ferroelectric phase to cubic paraelectric phase confirmed by high‐temperature X‐ray diffraction measurements. The diffused dielectric behavior arises mainly from the compositional fluctuation and/or the substitutional disorder in the arrangement of cations in the perovskite crystallographic sites. The frequency‐dependent remanent polarization scales well with the existing models of random field states, which indicates that the relaxor behavior correlates with the creation of chemical heterogeneity caused by localized cationic ordering. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nanobelts and nanocones of spinel Zn2SnO4
Authors: Li Y. , Ma X. L.
Published: January 2005

One‐dimensional nanostructures of ternary oxide spinel, Zn2SnO4, have been prepared for the first time on a large scale via a reaction between element Sn, ZnS and Fe(NO)3 at 1350 °C in a high‐temperature tube furnace. Scanning and transmission electron microscopic observations have confirmed that the as‐synthesized products consist of belt‐like and cone‐like single crystals. The dimensions of each nanobelt range from several hundred micrometers long, 100–500 nm wide, and several tens of nanometers thick. Formation mechanisms of these 1D nanostructures have been proposed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Studies of electronic excitations in MgMoO4, CaMoO4 and CdMoO4 crystals using VUV synchrotron radiation
Authors: Mikhailik V. B. , Kraus H. , Wahl D. , Mykhaylyk M. S.
Published: January 2005

Reflection, emission and luminescence spectra of Czochralski grown molybdate crystals, i.e. MgMoO4, CaMoO4 and CdMoO4 have been investigated over a 8–295 K temperature range using VUV synchrotron radiation. Preliminary interpretation of the spectroscopic properties has been carried out on the basis of present knowledge of the electronic structure and emission properties of these materials. The results of this study support the conclusion that molybdate crystals have good prospect for application in the search for rare events as cryogenic phonon‐scintillation detectors. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quadrupole moments of the alkali dimers, Li2, Na2, and K2
Authors: Harrison James F. , Lawson Daniel B.
Published: January 2005

The quadrupole moments (Θ) of Li2, Na2, and K2 have been determined using SCF, B3LYP, and CCSD(T). Included in this study is the effect of valence and core–valence correlation. The variation of Θ as a function of bond length has also been evaluated from which vibrational contributions have been determined. Additionally, the shape and relative magnitude of Θ vs. bond length are attributed to the s–s nature of the bonding. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Ab initio study of the insertion reactions of Sc+(1D) with HF, HCl, H2O, H2S, NH3, PH3, CH4, and SiH4
Authors: Ye Song , Wang Chaojie
Published: January 2005

The mechanism of scandium cation Sc+(1D) insertion into HF, HCl, H2O, H2S, NH3, PH3, CH4, and SiH4 has been investigated by ab initio molecular theory. All these reactions involve the initial formation of intermediate complexes followed by an H‐atom migration process via a transition state to insertion products. The Sc+(1D) insertion into eight compound reactions indicate that (i) the reaction with hydride of the right‐hand group is more exothermic than that of the left‐hand group and has a lower barrier, and (ii) the reaction with the second‐row hydride has a lower overall barrier and is less exothermic than with the first‐row hydride. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Theoretical investigation of the mechanism of the intermolecular proton transfer in carbanion [1.1]ferrocenophane
Authors: Broo Anders
Published: January 2005

Density Functional Theory calculations, with the hybrid functional denoted B3LYP, were used to study of the intramolecular proton transfer in lithium‐reacted [1.1]ferrocenophane (FCP). Geometries of ferrocene (FC) and several FCP complexes, including dimethylated FCP and lithium‐reacted FCP, were fully optimized utilizing the B3LYP and the INDO/1 methods. The B3LYP geometries agree very well with the available experimental geometries. The INDO/1 geometries agree less well but yield reasonable geometries for FC and the FCPs considered in this work. Transition state theory (TST) was used to calculate the intramolecular proton transfer rate in FCP−. Nuclear tunneling along the reaction coordinate was considered by the Wigner correction to the TST rate constant. Nuclear tunneling appears to be very important for the proton transfer. The calculated proton transfer rate at T = 298 K, kpt(298) is 98,690 s−1 and kpt(194) is 2 s−1 compared to the observed rate in tetrahydrofuran solution kobs(298) = 32,000 s−1 and kobs(194) = 63 s−1. A slightly different mechanism than the one previously suggested is proposed based on these calculations. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Computer‐aided design of a novel ligand for retinoic acid receptor in cancer chemotherapy
Authors: Silva Carlos H. T. P. , Leopoldino Andreia M. , Silva Eloiza H. T. , Espinoza V. A. A. , Taft C. A.
Published: January 2005

The isotypes of RAR and RXR are retinoic acid and retinoid X acid receptors, respectively, whose ligand‐binding domain contains the ligand‐dependent activation function, with distinct pharmacological targets for retinoids, involved in the treatment of various cancers and skin diseases. Due to the major challenge which cancer treatment and cure still imposes after many decades to the international scientific community, there is actually considerable interest in new ligands with increased bioactivity. We have focused on the retinoid acid receptor, which is considered an interesting target for drug design. In this work, we carried out density functional geometry optimizations and different docking procedures. We performed screening in a large database (hundreds of thousands of molecules which we optimized at the AM1 level) yielding a set of potential bioactive ligands. A new ligand was selected and optimized at the B3LYP/6‐31G* level. A flexible docking program was used to investigate the interactions between the receptor and the new ligand. The result of this work is compared with several crystallographic ligands of RAR. Our theoretically more bioactive new ligand indicates stronger and more hydrogen bonds as well as hydrophobic interactions with the receptor. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Atmospheric‐pressure laser ionization: a novel ionization method for liquid chromatography/mass spectrometry
Authors: Constapel M. , Schellenträger M. , Schmitz O. J. , Gäb S. , Brockmann K. J. , Giese R. , Benter Th.
Published: January 2005

We report on the development of a new laser‐ionization (LI) source operating at atmospheric pressure (AP) for liquid chromatography/mass spectrometry (LC/MS) applications. APLI is introduced as a powerful addition to existing AP ionization techniques, in particular atmospheric‐pressure chemical ionization (APCI), electrospray ionization (ESI), and atmospheric pressure photoionization (APPI). Replacing the one‐step VUV approach in APPI with step‐wise two‐photon ionization strongly enhances the selectivity of the ionization process. Furthermore, the photon flux during an ionization event is drastically increased over that of APPI, leading to very low detection limits. In addition, the APLI mechanism generally operates primarily directly on the analyte. This allows for very efficient ionization even of non‐polar compounds such as polycyclic aromatic hydrocarbons (PAHs). The APLI source was characterized with a MicroMass Q‐Tof Ultima II analyzer. Both the effluent of an HPLC column containing a number of PAHs (benzo[a]pyrene, fluoranthene, anthracene, fluorene) and samples from direct syringe injection were analyzed with respect to selectivity and sensitivity of the overall system. The liquid phase was vaporized by a conventional APCI inlet (AP probe) with the corona needle removed. Ionization was performed through selective resonance‐enhanced multi‐photon ionization schemes using a high‐repetition‐rate fixed‐frequency excimer laser operating at 248 nm. Detection limits well within the low‐fmol regime are readily obtained for various aromatic hydrocarbons that exhibit long‐lived electronic states at the energy level of the first photon. Only molecular ions are generated at the low laser fluxes employed (∼1 MW/cm2). The design and performance of the laser‐ionization source are presented along with results of the analysis of aromatic hydrocarbons. Copyright © 2005 John Wiley & Sons, Ltd.
Stable isotopically labeled internal standards in quantitative bioanalysis using liquid chromatography/mass spectrometry: necessity or not?
Authors: Stokvis Ellen , Rosing Hilde , Beijnen Jos H.
Published: January 2005

It appears to be a general belief that stable isotopically labeled (SIL) internal standards yield better assay performance results for quantitative bioanalytical liquid chromatography/mass spectrometry (LC/MS) assays than does any other internal standard. In this article we describe our experiences with structural analogues and SIL internal standards and their merits and demerits. SIL internal standards are the first choice, but deuterium‐labeled compounds may demonstrate unexpected behavior, such as different retention times or recoveries, than the analyte. In addition, a SIL internal standard with identical chemical properties as the analyte may cover up assay problems with stability, recovery, and ion suppression. Since SIL internal standards are not always available or are very expensive, structural analogues can be used, however, with consideration of several issues, which are usually displayed during method validation. Copyright © 2005 John Wiley & Sons, Ltd.
An automated system for stable isotope and concentration analyses of CO2 from small atmospheric samples
Authors: Schauer Andrew J. , Lott Michael J. , Cook Craig S. , Ehleringer James R.
Published: January 2005

We have developed an automated, continuous‐flow isotope ratio mass spectrometry (CF‐IRMS) system for the analysis of δ13C, δ18O, and CO2 concentration (μmol mol−1) ([CO2]) from 2 mL of atmospheric air. Two replicate 1 mL aliquots of atmospheric air are sequentially sampled from fifteen 100 mL flasks. The atmospheric sample is inserted into a helium stream and sent through a gas chromatograph for separation of the gases and subsequent IRMS analysis. Two δ13C and δ18O standards and five [CO2] standards are run with each set of fifteen samples. We obtained a precision of 0.06‰, 0.11‰, and 0.48 μmol mol−1 for δ13C, δ18O, and [CO2], respectively, by analyzing fifty 100 mL samples filled from five cylinders with a [CO2] range of 275 μmol mol−1. Accuracy was determined by comparison with established methods (dual‐inlet IRMS, and nondispersive infrared gas analysis) and found to have a mean offset of 0.00‰, −0.09‰, and −0.26 μmol mol−1 for δ13C and δ18O, and [CO2], respectively. Copyright © 2005 John Wiley & Sons, Ltd.
Determination of pharmaceutical compounds in aqueous dimethyl sulfoxide by electrospray ionization mass spectrometry
Authors: Borges Virginia , Henion Jack
Published: January 2005

Standard solutions of reserpine, dextromethorphan, imipramine and amitriptyline in dimethyl sulfoxide (DMSO), DMSO containing 0.1% formic acid, and DMSO/H2O (1:1, v/v) containing 0.1% formic acid were analyzed by positive electrospray ionization mass spectrometry (ESI‐MS). A triple‐quadrupole mass spectrometer equipped with a TurboIonspray (TIS) interface was used for the ESI‐MS analyses. The samples dissolved in the respective DMSO solution were infused directly into the mass spectrometer at 10 μL/min using an infusion pump. The positive Q1 full‐scan (m/z 50–650) mass spectrum of DMSO (MW = 78) showed three main peaks at m/z 79, 101 and 179, corresponding to the protonated molecule [DMSO+H]+, and the sodiated adducts [DMSO+Na]+ and [2DMSO+Na]+, respectively. The ESI of the compounds in DMSO and DMSO containing 0.1% formic acid was promoted by using the TIS gas (GS2) combined with the nebulizer gas (GS1), and TIS source temperature set to 250°C. In contrast, samples dissolved in DMSO/H2O (1:1, v/v) containing 0.1% formic were sprayed at a lower temperature (100°C) using only the nebulizer gas. The TIS voltage (V) was optimized in order to establish the lowest voltage necessary to achieve optimum ESI of each pharmaceutical compound with the voltage maintained below the onset potential required to produce a corona discharge at the TIS probe (sprayer). Detection limits of 10 ng/mL were achieved for reserpine, dextromethorphan, imipramine and amitriptyline in each solvent composition. Copyright © 2005 John Wiley & Sons, Ltd.
Development of a liquid chromatography/electrospray tandem mass spectrometry assay for the quantification of apicidin, a novel histone deacetylase inhibitor, in rat serum: application to a pharmacokinetic study
Authors: Shin Beom Soo , Kim John , Yoon Chi Ho , Kim Chul Hwan , Park Eun Hye , Han Jeung‐Whan , Yoo Sun Dong
Published: January 2005

Apicidin, a fungal metabolite isolated from Fusarium pallidoroseum, is a cyclic tetrapeptide that exhibits potent anti‐protozoal and anti‐angiogenic activities. Although extensive studies have been recently conducted to examine the biological and pharmacological action, no information is available on the quantitative analysis of apicidin. To our knowledge, this study is the first to describe a rapid and sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS) assay method for the quantification of apicidin in rat serum. The method was validated to demonstrate the specificity, linearity, recovery, lower limit of quantification (LLOQ), accuracy, and precision. The multiple reaction monitoring was based on the transitions m/z 624.7 → 84.3 and 372.1 → 176.1 for apicidin and trazodone, respectively. The assay utilized a single liquid‐liquid extraction and isocratic elution, and the LLOQ was 0.5 ng/mL using 0.1 mL of rat serum. The assay was linear over a range from 0.5–1000 ng/mL, with correlation coefficients >0.9994. The mean intra‐ and inter‐day assay accuracy ranged from 99.9–101.5% and 94.8–102.1%, respectively, and the mean intra‐ and inter‐day precision was between 2.7–5.9% and 1.6–11.5%, respectively. The developed assay method was applied to a pharmacokinetic study after intravenous injection of apicidin in rats at a dose of 1 mg/kg. Copyright © 2005 John Wiley & Sons, Ltd.
Person‐centered approaches to primary prevention in mental health: Situation‐focused and competence‐enhancement
Authors: Cowen Emory L.
Published: January 2005

Situation‐focused and competence‐enhancement approaches represent different pathways toward a richer person‐centered primary prevention in mental health. Each is valid in its own right. The utility of developing both strands rests precisely on the fact that they are different means to a common end. Thus, although the approaches have somewhat different conceptual footings (one is proactive, the other reactive), differ in immediate goals and tactics, and have characteristically different target groups and times of application, they come together around the shared ultimate goal of strengthening people's psychological well‐being.

How much “good” will accrue from energetic exploration and development of these two strands remains a moot point, around which some skepticism has already been voiced (Rappaport, 1981). The two approaches singly or in combination, do not substitute for the type of social reform and provision of life opportunities (based on the concepts of justice and distribution of power) that Rappaport advocates. Nor do they compete with it. During the long period in which informed social change will remain an ideal, surrounded by uncertainty about procedural steps and outcomes, effective development of the two person‐centered primary prevention strategies considered in this article can at least help to achieve a shorter‐term objective, i.e., replacing aspects of traditional mental health practice known to have limited potential for advancing psychological wellness.
When norms clash: international norms, domestic practices, and Japan's internalisation of the GATT/WTO
Authors: Cortell Andrew P. , Davis James W.
Published: January 2005

Almost twenty years old, the constructivist turn in international relations scholarship has succeeded in demonstrating the effects of norms, both in guiding the interactions of states with one another as well as influencing the domestic political debates that give rise to foreign policy outcomes. More recently, scholars have begun to study empirically the interactions between international and domestic normative systems. The origins of many international norms have been located in national understandings of what constitutes appropriate behaviour in a given issue area. The reverse, however, is also held to be true. Many national-level norms have been adopted after first finding their articulation in international institutions.
Sovereignty under attack: the international society meets the Al Qaeda network
Authors: Mendelsohn Barak
Published: January 2005

This article examines the complex relations between a violent non-state actor, the Al Qaeda network, and order in the international system. Al Qaeda poses a challenge to the sovereignty of specific states but it also challenges the international society as a whole. This way, the challenge that Al Qaeda represents is putting the survival of the system under risk. Consequently it requires that the international society will collectively respond to meet the threat. But challenges to both the practical sovereignty of states and to the international society do not have to weaken the system. Instead, such challenges if handled effectively may lead to the strengthening of the society of states: a robust international society is dynamic and responsive to threats. Its members could cooperate to adapt the principles and the institutions on which the system is founded to new circumstances. Through its focus on the preservation qualities of the international society this article also reinforces the significance of the English School to the study of international relations. It raises important questions that could be answered in the framework of the English School.
Domestic threats, regional solutions? The challenge of security integration in Southern Africa
Authors: Hammerstad Anne
Published: January 2005

The article discusses the salience of different theories of regional security integration through the prism of the experience of the Southern African Development Community (SADC). It tracks the region's progress from a hostile security complex to a nascent security community and asks what strategy for security integration should be employed to continue this positive trend. Although Southern African leaders seem to prefer a collective security strategy à la NATO, the common security approach of the OSCE is more appropriate: most of the region's security threats are domestic and lack of capacity warrants an incremental, decentralised process focused on the weakest SADC members. The current state-centric approach, which tends to conflate the security needs of regimes with those of the population as a whole, will not further the cause of building a security community in Southern Africa.
Speaking and hearing' Habermasian discourse ethics, feminism and IR
Authors: Hutchings Kimberly
Published: January 2005

It is impossible not to encounter Habermas as an important interlocutor in the fields of critical theory, feminist theory and international relations theory across which I work. He is the outstanding critical theorist of his generation, in the tradition of critique which was carried through the Frankfurt School and traces itself back to Kant, Hegel and Marx. And for feminists and international relations theorists, he represents one of the directions in which feminist theory or post-positivist IR could develop, deepening its epistemological and sociological understanding without sacrificing the possibility of the rationally grounded critique of contemporary world politics. This article is the beginning of an attempt to trace through layers of difficulty encountered in using Habermas as a normative resource for a particular version of feminist international theory, which understands feminism to be a transnational, cosmopolitan (but not univocal) project, neither authorised nor legitimised by any foundational ground or teleological end. I will argue that although Habermas's notion of discourse ethics seems initially promising as a way forward for non-foundational feminist theory, in the end any ‘dialogue’ on Habermasian terms turns out to be one-sided and exclusive.
Optimal design of a micro parallel positioning platform. Part II: Real machine design
Authors: Oh Kun-Ku , Liu Xin-Jun , Kang Deuk Soo , Kim Jongwon
Published: January 2005

In part I of this paper (previous issue of Robotica) a dual stage system with the coarse and fine actuators is adopted to achieve sub-micron accuracy with a large working space for the proposed new three degree-of-freedom (DOF) miniaturized micro parallel mechanism with high mobility and one type of the architecture with vertical actuator locations in all three legs (C-VV type) among six possible coarse actuator architectures is selected for the coarse actuator architecture.

In this part of the paper, an optimal kinematic parameter set is determined for the selected coarse actuator architecture. To determine this set, the design tool of the physical model of the solution space (PMSS) and the evaluation of the conditioning index (CI) and global mobility conditioning index (GMCI) are used. The basic size of the micro parallel mechanism is 45.0 mm×22.5 mm×22.9 mm with 100° mobility, the workspace 5.0 mm (y-axis)×5.0 mm (z-axis), and sub-micron resolution. After finishing the design of the main coarse actuator architecture, one architecture among six possible fine actuator architectures is selected to achieve sub-micron positioning accuracy based on the requirements of the continuous fine motion and smaller platform resolution. The selected coarse-and-fine actuator combination is used for the micro positioning platform for laser-machining application.
A simplified propulsive model of bio-mimetic robot fish and its realization
Authors: Yu Junzhi , Wang Shuo , Tan Min
Published: January 2005

This paper presents a simplified kinematics propulsive model for carangiform propulsion. The carangiform motion is modeled as a serial $N$-joint oscillating mechanism that is composed of two basic components: the streamlined fish body represented by a planar spline curve and its lunate caudal tail by an oscillating foil. The speed of fish's straight swimming is adjusted by modulating the joint's oscillatory frequency, and its orientation is tuned by different joint's deflections. The experimental results showed that the proposed simplified propulsive model could be a viable candidate for application in aquatic swimming vehicles.
Open-loop stable running
Authors: Mombaur Katja D. , Longman Richard W. , Bock Hans Georg , Schlöder Johannes P.
Published: January 2005

We present simulated monopedal and bipedal robots that are capable of open-loop stable periodic running motions without any feedback even though they have no statically stable standing positions. Running as opposed to walking involves flight phases which makes stability a particularly difficult issue. The concept of open-loop stability implies that the actuators receive purely periodic torque or force inputs that are never altered by any feedback in order to prevent the robot from falling. The design of these robots and the choice of model parameter values leading to stable motions is a difficult task that has been accomplished using newly developed stability optimization methods.
Compensatory motion control for a biped walking robot
Authors: Lim Hun-ok , Takanishi Atsuo
Published: January 2005

This paper addresses a compensatory motion control algorithm of a biped robot to deal with stable dynamic walking on even or uneven terrain. This control algorithm consists of three main parts; the introduction of a virtual plane to consider ZMP (Zero Moment Point); an iteration algorithm to compute the trunk motion; and a program control to realize dynamic walking. The virtual plane is defined as a plane formed by the support points between the surface of terrain and the soles. In order to obtain the trunk motion capable of compensating for the moments produced by the motion of the lower-limbs during the walking, ZMP equation on the virtual plane is computed by using an iteration method. Also, a walking pattern is presented which is composed of the trajectories of lower-limbs, waist and trunk. The walking pattern is commanded to the joints of WL-12RIII (Waseda Leg-Twelve Refined Three) using a program control method. Through walking simulations and experiments on an uneven terrain, such as stairs and sloped terrain, the effectiveness of the control method is verified.
Distance and Speed Errors in ARPA Systems
Authors: Lenart Andrzej S.
Published: January 2005

Errors of different positioning algorithms for tracked targets used in the ARPA systems and their influence on estimated speed of targets is analysed. Examples show their significance in tracking targets at low ranges.
Attitude Determination from GNSS Using Adaptive Kalman Filtering
Authors: El-Mowafy Ahmed , Mohamed Ahmed
Published: January 2005

An adaptive Kalman filtering approach is proposed for attitude determination to replace the fixed (conventional) Kalman filtering approach. The filter is used to adaptively reflect system dynamics changes or rapid changes in vehicle trajectory. The estimation procedure is carried out through the use of a measurement residual sequence. The sequence is used as a piece-wise stationary process inside an estimation window. The measurement noise covariance matrix and the system noise matrix are adaptively estimated. An extended Kalman filter approach with iteration of the states within-an-epoch was performed to overcome the non-linearity of the observation equations. A test was performed to evaluate the proposed technique. Different trajectory scenarios are presented to show the difference in performance between the adaptive Kalman filter and the conventional one. Results show that the proposed adoptive filtering approach has a better performance than the conventional filter.
Evaluation of a New Method of Heading Estimation for Pedestrian Dead Reckoning Using Shoe Mounted Sensors
Authors: Stirling Ross , Fyfe Ken , Lachapelle Gérard
Published: January 2005

In this paper, a novel method of sensor based pedestrian dead reckoning is presented using sensors mounted on a shoe. Sensor based systems are a practical alternative to global navigation satellite systems when positioning accuracy is degraded such as in thick forest, urban areas with tall buildings and indoors. Using miniature, inexpensive sensors it is possible to create self-contained systems using sensor-only navigation techniques optimised for pedestrian motion. The systems developed extend existing foot based stride measurement technology by adding the capability to sense direction, making it possible to determine the path and displacement of the user. The proposed dead-reckoning navigation system applies an array of accelerometers and magneto-resistive sensors worn on the subject's shoe. Measurement of the foot's acceleration allows the precise identification of separate stride segments, thus providing improved stride length estimation. The system relies on identifying the stance phase to resolve the sensor attitude and determine the step heading. Field trials were carried out in forested conditions. Performance metrics include position, stride length estimation and heading with respect to a high accuracy reference trajectory.
Concerning Cross Track Distance at Mid-Longitude (1)
Authors: Ponsonby John
Published: January 2005

I was amused by the Cross Track Distance at Mid-Longitude problem posed by Paul Hickley in The Journal of Navigation57, 320. Thinking about it, I came up with a solution. My method gives an astonishingly accurate, though approximate, answer which is found without any appeal to any formula of spherical trigonometry.
Concerning Cross Track Distance at Mid-Longitude (2)
Authors: Hoare Peter
Published: January 2005

I wish to respond to Paul Hickley's invitation in his article on “Great Circle Versus Rhumb Line Cross-Track Distance at Mid-Longitude” in the May 2004 Journal of Navigation. It seemed an ideal teaser for an erstwhile Maps and Charts lecturer, albeit 45 years ago, to play with on his 81st birthday last week! Since it was a question for pilots, did not require knowledge of spherical trig, and was answerable in 2 minutes and 12 seconds I thought, as did Paul, that there must be a fairly simple solution. Mine follows.
Surface folding of viscoelastic fluids: finite elasticity membrane model
Authors: PODGORSKI T. , BELMONTE A.
Published: January 2005

When a dry sphere sinks into a fluid, a funnel-shaped free surface develops behind the sphere if the sinking occurs faster than the surface wetting. If the fluid is viscoelastic, the interface can become unstable to a loss of axisymmetry. The stress near this surface concentrates into boundary layers, as also seen in other free surface extensional flows of viscoelastic fluids. At high Deborah number and low Reynolds number, the qualitative behaviour can be recovered by considering the static equilibrium of a stretched elastic membrane in an hydrostatic pressure field. We treat this problem in the framework of finite elasticity using a neo-Hookean constitutive model, and show how the conditions of instability can be recovered. A numerical study of this model is presented.
A continuum model of lipid bilayers
Authors: BLOM J. G. , PELETIER M. A.
Published: January 2005

We study a one-dimensional continuum model for lipid bilayers. The system consists of water and lipid molecules; lipid molecules are represented by two ‘beads’, a head bead and a tail bead, connected by a rigid rod. We derive a simplified model for such a system, in which we only take into account the effects of entropy and hydrophilic/hydrophobic interactions. We show that for this simple model membrane-like structures exist for certain choices of the parameters, and numerical calculations suggest that they are stable.
Worlds of Welfare and the Health Care Discrepancy
Authors: Bambra Clare
Published: January 2005

The nature of welfare regimes has been an ongoing debate within the comparative social policy literature since the publication of Esping-Andersen's ‘Three Worlds of Welfare’ (1990). This article draws upon recent developments within this debate, most notably Kasza's assertions about the ‘illusory nature’ of welfare regimes, to highlight the health care discrepancy. It argues that health care provision has been a notable omission from the wider regimes literature and one which, if included in the form of a health care decommodification typology, can give credence to Kasza's perspective by highlighting the diverse internal arrangements of welfare states and welfare state regimes.
Introduction: Disabled People and Social Justice
Authors: Goodlad Robina , Riddell Sheila
Published: January 2005

In the 1970s and early 1980s, discussions of social justice in the social science literature focused largely on social class. The implicit assumption of much of the literature was that a more just society would be achieved through the reduction of inequalities in the distribution of economic and social resources. Since then, there has been a growing focus on plural aspects of social justice. Many writers now distinguish between distributive, cultural and associational aspects of social justice. However, the different implications of these facets of social justice for different groups, and potential tensions between them, have rarely been adequately recognised. Given New Labour's focus on social justice, and its belief that attaining greater social justice is compatible with achieving greater efficiency in the public sector, there is a need to examine more closely the understandings of social justice underpinning a range of policy initiatives.