bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural and Electrochemical Studies of Dimerization and Rotational Isomerization in Multi‐Iron Silicotungstates
Authors: Anderson Travis M. , Cao Rui , Neiwert Wade A. , Hardcastle Kenneth I. , Hill Craig L. , Ammam Malika , Keita Bineta , Nadjo Louis
Published: April 2005

A structural and electrochemical investigation of dimerization and Baker–Figgis (rotational) isomerization in the tri‐ferric‐substituted silicotungstates has been undertaken because these phenomena are important in a large number of polyoxometalates. A single‐crystal X‐ray diffraction analysis of K4Na7[(β‐SiFe3W9(OH)3O34)2(OH)3] (β1) has been carried out [a = 12.9709(7) Å, b = 38.720(2) Å, c = 21.4221(12) Å, orthorhombic, Pbcm, R1 = 8.48 %, based on 13809 independent reflections]. The complex is isostructural with [(α‐SiFe3W9(OH)3O34)2(OH)3]11– (α1) except that the edge‐shared W3O13 caps in each [SiFe3W9(OH)3O34]4– unit are rotated by 60°. Electrochemical measurements, performed in a pH 5 acetate buffer, indicate a positive shift in the FeIII‐based peak potential (and no change for the WVI‐based potential) upon going from α1 to its monomeric derivative [(α‐Si(FeOH2)3W9(OH)3O34)]4– (α2) (–0.484 ± 0.005 V and –0.474 ± 0.005 V, respectively). In contrast, the peak potentials of the FeIII‐ and WVI‐based redox processes of β1 are both found at more negative values than its rotational isomer α1. The absolute values of the reduction peak potential differences are 0.022 V for FeIII and 0.162 V for WVI. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Physical and functional interactions between the human DNMT3L protein and members of the de novo methyltransferase family
Authors: Chen Zhao‐Xia , Mann Jeffrey R. , Hsieh Chih‐Lin , Riggs Arthur D. , Chédin Frédéric
Published: April 2005

The de novo methyltransferase‐like protein, DNMT3L, is required for methylation of imprinted genes in germ cells. Although enzymatically inactive, human DNMT3L was shown to act as a general stimulatory factor for de novo methylation by murine Dnmt3a. Several isoforms of DNMT3A and DNMT3B with development‐stage and tissue‐specific expression patterns have been described in mouse and human, thus bringing into question the identity of the physiological partner(s) for stimulation by DNMT3L. Here, we used an episome‐based in vivo methyltransferase assay to systematically analyze five isoforms of human DNMT3A and DNMT3B for activity and stimulation by human DNMT3L. Our results show that human DNMT3A, DNMT3A2, DNMT3B1, and DNMT3B2 are catalytically competent, while DNMT3B3 is inactive in our assay. We also report that the activity of all four active isoforms is significantly increased upon co‐expression with DNMT3L, albeit to varying extents. This is the first comprehensive description of the in vivo activities of the poorly characterized human DNMT3A and DNMT3B isoforms and of their functional interactions with DNMT3L. To further elucidate the mechanism by which DNMT3L stimulates DNA methylation, we have mapped in detail the domains that mediate interaction of human DNMT3L with human DNMT3A and DNMT3B. Our results show that the C‐terminus of DNMT3L is the only region required for interaction with DNMT3A and DNMT3B and that interaction takes place through the C‐terminal catalytic domain of DNMT3A and DNMT3B. The implications of these findings for the regulation of de novo methyltransferases and genomic imprinting are discussed. This article contains Supplementary Material available at http://www.mrw.interscience.wiley.com/suppmat/0730‐2312/suppmat/2005/95/chen.html. © 2005 Wiley‐Liss, Inc.
Induction of an epithelial to mesenchymal transition in human immortal and malignant keratinocytes by TGF‐β1 involves MAPK, Smad and AP‐1 signalling pathways
Authors: Davies Maria , Robinson Max , Smith Emily , Huntley Suzy , Prime Stephen , Paterson Ian
Published: April 2005

Recent data indicate that transforming growth factor‐β1 (TGF‐β1) can act to promote tumour progression in the late stages of carcinogenesis. The mechanism by which this occurs is unknown although a ligand‐induced epithelial–mesenchymal transition (EMT) is thought to be important. In this study, we demonstrate that active Ras is required for TGF‐β1‐induced EMT in human keratinocytes and that epidermal growth factor (EGF) can substitute for mutant Ras. EMT was reversed by the removal of TGF‐β1. Under conditions of TGF‐β1‐induced EMT, cells were growth inhibited by the ligand resulting in G1 arrest. In cells containing normal Ras, TGF‐β1‐activated ERK and p38 mitogen‐activated protein kinases (MAPKs), and levels of activation were further increased by co‐treatment with EGF. Inhibition of MAPK pathways and Smad2/3 signalling blocked the induction of EMT by TGF‐β1. Further, inhibition of the AP‐1 transcriptional complex by [6]‐Gingerol, or by the ectopic expression of JDP2, blocked TGF‐β1‐induced EMT and conversely, stimulation of AP‐1 by 12‐O‐tetradecanoylphorbol 13‐acetate (TPA) substituted for EGF in the induction of EMT by TGF‐β1 in cells containing normal Ras. The presence of oncogenic Ras, the treatment of cells with EGF, or the treatment of cells with TPA to activate AP‐1, potentiated TGF‐β1‐induced Smad‐dependent transcription, an effect that was attenuated by the inhibition of MAPKs and AP‐1. The results demonstrate that active Ras and TGF‐β1 co‐operate to reversibly induce EMT in human keratinocytes by mechanisms that involve MAPKs, Smad2/3 and AP‐1. Further we demonstrate that MAPK/AP‐1 signalling enhances Smad transcriptional activity under conditions associated with TGF‐β1‐induced EMT. © 2005 Wiley‐Liss, Inc.
Distribution of Substituents along the Cellulose Chain on Cellulose Xanthate and Carboxymethyl Cellulose
Authors: Fischer Klaus , Krasselt Karsten , Schmidt Ingeborg , Weightman Derek
Published: April 2005

The distribution of substituents of cellulose xanthogenate and carboxymethyl cellulose along the cellulose chains and therefore in relation to the molecular mass can be measured using size exclusion chromatography including a multi angle laser light scattering and mass detection for determining the molecular mass of the derivative assisted by an UV‐ detection for determining the xanthate groups and carboxymethyl groups after derivatisation, respectively. The results investigating cellulose xanthogenate show that the temperature used in dissolving xanthogenate and in ripening viscose influences the distribution of xanthate groups in a different way; but all steps processing viscose are connected with a loss in the degree of substitution in ripening the distribution of substitution additionally becomes more even.

The investigated carboxymethyl cellulose revealed different distribution of carboxylic groups in dependence on the viscosity of the CMC.
A Novel Method for Analysis of Xanthate Group Distribution in Viscoses
Authors: Rußler Axel , Lange Thomas , Potthast Antje , Rosenau Thomas , Berger‐Nicoletti Elena , Sixta Herbert , Kosma Paul
Published: April 2005

Analytical monitoring of xanthation in the viscose process along with xanthate group analysis in the viscose material is a long‐debated problem in cellulose chemistry. The task is rendered extremely intricate by the lability of the starting material and the harshness of the reaction medium, which adds to a lack of suitable analytical approaches. In a four‐years' endeavor in our lab, a method is being developed which allows to analyze the distribution of xanthate groups in viscoses relative to the anhydroglucose units and along the cellulose chain.

In a first step the xanthate groups are stabilized by alkylation, which was optimized towards quantitative conversion. In a second step, the remaining free hydroxyl groups are protected by carbanilation, followed by selective removal of the stabilized xanthate groups. Steps two and three thus generate an inverse image of the initial xanthate pattern. In the forth and fifth step, the liberated hydroxyl groups are methylated, and the carbanilates are removed, so that in the overall process the xanthates were replaced by methyl groups. All reaction steps have been comprehensively tested with regard to completeness of conversion and orthogonality of the protecting groups.
Prehydrolysis Sulfite Revisited
Authors: Fasching Mario , Griebl Andreas , Kandioller Gottfried , Zieher Andrea , Weber Hedda , Sixta Herbert
Published: April 2005

The prehydrolysis of beech wood in water at different temperatures and the impact of this treatment on further pulping stages were explored. Both, increased condensation degree and an increased number of free phenolic hydroxyl groups were found in the lignin isolated after prehydrolysis. An intermediate alkaline extraction (using either NaOH or MgO as base) following the prehydrolysis was explored. Finally, acid sulfite cooks of the differently pre‐treated materials were performed, and the obtained materials thoroughly analyzed.
Complexes of diphenylarsinic acid and phenylarsonic acid with thiols: a 1H and 13C NMR study
Authors: Nakayama Takashi , Isobe Tomohiko , Nakamiya Kunichika , Edmonds John S. , Shibata Yasuyuki , Morita Masatoshi
Published: April 2005

The high toxicity of diphenylarsinic acid, found in ground water and well water as a probable consequence of the inappropriate disposal of warfare agents, prompted us to study the reaction, monitored by 1H and 13C NMR spectroscopy, of the compound and its monophenyl analogue, phenylarsonic acid, with cellular thiols as represented, in particular, by glutathione. Glutathione reduced the phenylarsenic acids to trivalent forms and complexed them: diphenylarsinic acid to a monoglutathione adduct and phenylarsonic acid to a diglutathione adduct. The complexes were characterized by 1H and 13C NMR spectroscopy and mass spectrometry. The NMR spectra showed the diastereotopic nature of the two phenyl groups in the diphenylarsinic acid–glutathione compound, and of the two glutathione residues in the phenylarsonic acid–diglutathione complex. The stereochemistry of thiol compounds of phenylarsonic acid was further explored by 1H and 13C NMR spectroscopy of the L‐cysteine complex. The diphenylarsinic acid–glutathione complex was stable below pH 12 but at higher pH the complex dissociated into diphenylarsinous acid and reduced glutathione. The released diphenylarsinous acid then oxidized to diphenylarsinic acid with a half‐life of about 7 h at pH 13 and at room temperature. Copyright © 2005 John Wiley & Sons, Ltd.
Ring‐substituted benzohydroxamic acids: 1H, 13C and 15N NMR spectra and NHOH proton exchange
Authors: Schraml Jan , Tkadlecová Marcela , Pataridis Statis , Soukupová Ludmila , Blechta Vratislav , Roithová Jana , Exner Otto
Published: April 2005

NMR spectra (1H, 13C, 15N) of para‐ and meta‐substituted benzohydroxamic acids were studied in dry dimethyl sulfoxide solutions. The 13C chemical shifts were very close to those found by cross‐polarization magic angle spinning in solids, the hydroxamic (not hydroximic) structure of which is unambiguous. The hydroxamic structure of these acids in DMSO solutions was proved independently by their 15N chemical shifts. The 15N and 1H chemical shifts of the NHOH fragment showed excellent mutual dependences and dependences on the nature of the ring substituent. According to these dependences and ab initio energy calculations, all the acids assume the same Z conformation. Proton exchange between hydroxamic OH and NH groups in DMSO proceeded by both intra‐ and intermolecular exchange and the rates did not exhibit any simple relationship to the substituent constants. Copyright © 2005 John Wiley & Sons, Ltd.
Spikes in two coupled nonlinear Schrödinger equations
Authors: Lin Tai-Chia , Wei Juncheng
Published: April 2005

Here we study the interaction and the configuration of spikes in a double condensate by analyzing least energy solutions of two coupled nonlinear Schrödinger equations which model Bose–Einstein condensates of two different hyperfine spin states. When the interspecies scattering length is positive and large enough, spikes of a double condensate repel each other and behave like two separate spikes. In contrast, spikes of a double condensate attract each other and behave like a single spike if the interspecies scattering length is negative and large enough. Our mathematical arguments can prove such physical phenomena. We first use Nehari's manifold to construct least energy solutions, and then use some techniques of singular perturbation problems to derive the asymptotic behavior of least energy solutions. It is shown that the interaction term determines the locations of the two spikes and the asymptotic shape of least energy solutions.

Nous étudions l'interaction et la disposition des pics pour un condensat double. Notre méthode utilise l'analyse des solutions avec énergie minimale des deux équations de Schrödinger couplées non linéaires qui modèlent le condensat de Bose et Einstein pour deux états des spins différents hyperfinis. Si la longueur de dispersion entre espèces est positive et suffisamment gande, les pics pour un condensat double se repoussent, et se comportent comme deux pics séparés. En revanche pour un condensat double s'attirent et se comportent comme un seul pic ; la longueur de dispersion entre espèces est négative et suffisamment petite. Nos arguments mathématiques établissent rigoureusement ses phénomènes physiques. Nous utilisons d'une part la variété de Nehari pour la construction de solutions avec énergie minimale et d'autre part les techniques de problèmes de perturbation singulière pour la dérivation du comportement asymptotique de la solutions avec énergie minimale. Nous démontrons que le terme d'interaction détermine la position des pics et la forme asymptotique des solutions avec énergie minimale.
The multi-dimensional super-replication problem under gamma constraints
Authors: Soner H. Mete , Touzi Nizar , Cheridito Patrick
Published: April 2005

The classical Black–Scholes hedging strategy of a European contingent claim may require rapid changes in the replicating portfolio. One approach to avoid this is to impose
a priori
bounds on the variations of the allowed trading strategies, called gamma constraints. Under such a restriction, it is in general no longer possible to replicate a European contingent claim, and super-replication is a commonly used alternative. This paper characterizes the infimum of the initial capitals that allow an investor to super-replicate the contingent claim by carefully choosing an investment strategy obeying a gamma constraint. This infimum is shown to be the unique viscosity solution of a nonstandard partial differential equation. Due to the lower gamma bound, the “intuitive” partial differential equation is not parabolic and the actual equation satisfied by the infimum is the parabolic majorant of this equation. The derivation of the viscosity property is based on new results on the small time behavior of double stochastic integrals.

La stratégie de couverture classique d'une option européenne, dictée par le modèle de Black et Scholes, peut conduire à des rebalancements rapides du portefeuille répliquant. Afin d'éviter de telles situations indésirables, nous introduisons des contraintes spécifiques sur le portefeuille, appelées
contraintes gamma
. Il n'est alors pas possible en général de répliquer parfaitement l'option européene. Par conséquent, la surréplication est alors une alternative fréquemment utilisée. Dans ce papier, on caractérise l'infimum des capitaux initiaux qui permet à un investiseur de surrépliquer l'actif contingent en choisissant soigneusement une stratégie de portefeuile satisfaisant à une contrainte gamma. Nous montrons que cet infimum est l'unique solution de viscosité d'une équation aux dérivées partielles non standard. A cause de la borne inférieure sur la contrainte gamma, l'équation aux dérivées partielles « intuitive » n'est pas parabolique, et l'équation effectivemet satisfaite par l'infimum est le mojorant parabolique de l'équation « intuitive ». L'obtention de la propriété de viscosité s'appuie sur des résultats nouveaux portant sur des intégrales stochastiques doubles.
Semilinear equations with exponential nonlinearity and measure data
Authors: Ponce Augusto C. , Bartolucci Daniele , Leoni Fabiana , Orsina Luigi
Published: April 2005

We study the existence and non-existence of solutions of the problem

\tag{0.1}
\begin{cases} −\mathrm{\Delta }u + \mathrm{e}^{u}−1 = \mu & \mathrm{in}\:\Omega , \\ u = 0 & \mathrm{on}\:\partial \Omega ,
\end{cases}

where

Ω

is a bounded domain in

\mathbb{R}^{N}

,

N⩾3

, and

μ

is a Radon measure. We prove that if

\mu ⩽4\pi \mathcal{H}^{N−2}

, then (0.1) has a unique solution. We also show that the constant

4π

in this condition cannot be improved.

Nous étudions l'existence et la non existence des solutions de l'équation

\tag{0.2}
\begin{cases} −\mathrm{\Delta }u + \mathrm{e}^{u}−1 = \mu & \mathrm{dans}\:\Omega , \\ u = 0 & \mathrm{sur}\:\partial \Omega ,
\end{cases}

où

Ω

est un domaine borné dans

\mathbb{R}^{N}

,

N⩾3

, et

μ

est une mesure de Radon. Nous démontrons que si

μ

vérifie

\mu ⩽4\pi \mathcal{H}^{N−2}

, alors le problème (0.2) admet une unique solution. Nous montrons que la constante

4π

dans cette condition ne peut pas être améliorée.
Heart failure programmes in countries with a primary care‐based health care system. Are additional trials necessary? Design of the DEAL‐HF study
Authors: de la Porte Pieta W.F. Bruggink‐André , Lok Dirk J.A. , van Wijngaarden Jan , Cornel Jan H. , Pruijsers‐Lamers Dian , van Veldhuisen Dirk J. , Hoes Arno W.
Published: April 2005

Background

Several randomised studies of heart failure (HF) management programmes in the United States, Australia and Europe have shown a considerable reduction in hospitalisation rates for HF. In this article, a comprehensive review of these studies will be provided and their applicability to countries, with a primary care‐based healthcare system, will be discussed. In addition, the design of the Deventer‐Alkmaar HF Project (DEAL‐HF), a randomised study of the effect of a nurse and physician‐directed intervention over 1 year in The Netherlands, will also be presented.

Aim

To discuss the applicability of the results of available studies on heart failure management programmes to countries with well‐structured primary care facilities and to determine whether additional trials should be conducted in these countries.

Methods

We performed a literature search in PubMed. In a review of the available studies, essential methodological aspects, in particular, the population involved, the sample size, follow‐up period, setting, type of intervention, and the outcome parameters, are discussed critically. Also, the applicability of these studies to countries with a primary care‐based healthcare system and easy access to medical care is evaluated.

Conclusion

Applicability of the results of the available studies on the efficacy of heart failure management programmes to countries with a primary care‐based health care system is doubtful. An efficacy trial in a country with a well‐established primary care‐based healthcare system, such as The Netherlands, is due to report soon (DEAL‐HF).
Anti‐inflammatory effects of continuous passive motion on meniscal fibrocartilage
Authors: Ferretti Mario , Srinivasan Abiraman , Deschner James , Gassner Robert , Baliko Frank , Piesco Nicholas , Salter Robert , Agarwal Sudha
Published: April 2005

Motion‐based therapies have been applied to promote healing of arthritic joints. The goal of the current study was to determine the early molecular events that are responsible for the beneficial actions of motion‐based therapies on meniscal fibrocartilage. Rabbit knees with Antigen‐Induced‐Arthritis (AIA) were exposed to continuous passive motion (CPM) for 24 or 48 h and compared to immobilized knees. The menisci were harvested and glycosaminoglycans (GAG), interleukin‐1β (IL‐1β), matrix metalloproteinase‐1 (MMP‐1), cyclooxygenase‐2 (COX‐2), and interleukin‐10 (IL‐10) were determined by histochemical analysis.

Within 24 h, immobilized knees exhibited marked GAG degradation. The expression of proinflammatory mediators MMP‐1, COX‐2, and IL‐1β was notably increased within 24 h and continued to increase during the next 24 h in immobilized knees. Knees subjected to CPM revealed a rapid and sustained decrease in GAG degradation and the expression of all proinflammatory mediators during the entire period of CPM treatment. More importantly, CPM induced synthesis of the anti‐inflammatory cytokine IL‐10. The results demonstrate that mechanical signals generated by CPM exert potent anti‐inflammatory signals on meniscal fibrochondrocytes. Furthermore, these studies explain the molecular basis of the beneficial effects of CPM observed on articular cartilage and suggest that CPM suppresses the inflammatory process of arthritis more efficiently than immobilization. © 2005 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
The polar ship Scotia
Authors: Erskine Angus B. , Kjær Kjell-G.
Published: April 2005

The ship that the oceanographer Dr William Speirs Bruce used on the Scottish National Antarctic Expedition, 1902–04, was originally a sealer named Hekla, built in Norway in 1872. In 1889 the Norwegian skipper Ragnvald Knudsen explored the northeast coast of Greenland between latitudes 74° and 75°, and in 1891–92 the ship was used by the Danish naval officer, Lieutenant C. Ryder, to explore the inner recesses of Scoresby Sund, finally visiting Angmagssalik. In 1902, re-named Scotia and captained by Tam Robertson from Peterhead, she sailed to the Weddell Sea under the leadership of Bruce. The southern winter of 1903 was spent at Laurie Island in the South Orkney Islands, and in March–April 1904 the party discovered 150 miles of previously unknown coastline of the Antarctic continent, reaching a farthest south of 74°01′S, 22°00′W. An extensive programme of marine survey and biological research was carried out. Back in the UK, Bruce sold the ship, and she returned to sealing, based in Dundee until appointed to be the first international North Atlantic Ice Patrol ship after the tragedy of Titanic. The Great War caused her to become a freighter in the English Channel area until she caught fire and was burnt out on a sandbank in the Bristol Channel on 18 January 1916.
Two components of ionospheric plasma structuring at midlatitudes observed during the large magnetic storm of October 30, 2003
Authors: Basu Su. , Basu S. , Makela J. J. , Sheehan R. E. , MacKenzie E. , Doherty P. , Wright J. W. , Keskinen M. J. , Pallamraju D. , Paxton L. J. , Berkey F. T.
Published: April 2005

We consider VHF amplitude scintillations, GPS phase fluctuations, ionosonde measurements, maps of GPS total electron content (TEC), observations of daytime aurora and TIMED GUVI images during the large magnetic storms of October 29–31, 2003, and find two distinct classes of plasma processes that produce midlatitude ionospheric irregularities. One is associated with auroral plasma processes; the other, with storm enhanced density (SED) gradients, a part of which occur in close proximity to sub‐auroral polarization stream (SAPS) electric fields as discussed by J. C. Foster et al. (2002). We analyze in detail the storm event of October 30, 2003. The SAPS‐associated plasma structures may occur by an ion temperature gradient convective instability (M. J. Keskinen et al., 2004), but structuring by auroral processes requires elucidation.
Excitation of the ionospheric resonance cavity by thunderstorms
Authors: Surkov V. V. , Molchanov O. A. , Hayakawa M. , Fedorov E. N.
Published: April 2005

Excitation of the middle latitude ionospheric Alfvén resonator (IAR) due to global thunderstorm activity is considered. The lightning discharges in thunderstorm centers are modeled in terms of a stochastic Poisson process. The lightning onset time and the current moment amplitude are supposed to be random values, while the shape of current moment is assumed to be a given function. Electromagnetic TM mode radiated from the lightning discharges penetrates into the ionosphere via mode coupling to the shear Alfvén and magnetosonic wave modes in the E layer of the ionosphere. The ionospheric resonance cavity can trap and accumulate the shear Alfvén wave energy with periods from one second to a few tenths of seconds, thereby exciting the IAR resonances. Using a simplified model of the topside ionosphere, we have analyzed a possibility for the IAR excitation far from the tropical thunderstorm region. The low‐frequency power spectra of the IAR on the ground surface is studied both analytically and numerically. It is shown that the IAR power spectra exhibit spectral resonance structure (SRS) only during the nighttime conditions. Furthermore, it is found that the calculated spectra are one or two orders of magnitude lower than that observed at Karimshino station in Kamchatka region. This fact suggests that the SRS is not simply due to stochastic lightning discharge process but that some generation mechanisms for the IAR excitation at middle latitudes might also be operative.
Type curve analyses of pneumatic single‐hole tests in unsaturated fractured tuff: Direct evidence for a porosity scale effect
Authors: Illman Walter A.
Published: April 2005

A large number of single‐ and cross‐hole pneumatic injection tests have been conducted in shallow vertical and inclined boreholes in unsaturated fractured tuff at the Apache Leap Research Site (ALRS) near Superior, Arizona. Previously, direct and indirect evidence for a permeability scale effect was provided through the analysis of these tests. Direct evidence was based on the comparison of small‐scale single‐hole and larger‐scale cross‐hole test results obtained through the type curve and steady state analysis of these data separately. Indirect evidence was provided by comparing cross‐hole test analyses conducted at fine and coarse scales of resolution by means of a three‐dimensional numerical inverse model. The latter study also provided indirect evidence for a porosity scale effect. However, there were no small‐scale porosity data from single‐hole tests to directly verify this indirect evidence. This paper presents such data generated through the type curve interpretation of the recovery phase of the single‐hole tests conducted at a nominal 1‐m scale providing direct evidence for a porosity scale effect at the site. Statistical analysis of results revealed a strong porosity scale effect confirming an earlier finding obtained indirectly. These results also showed that (1) the injection phase of the pneumatic single‐hole tests do not yield reliable estimates of porosity but the recovery phase are amenable to type curve interpretation, (2) flow dimensionality of single‐hole tests at 1‐m scale are three‐dimensional across the site except for a few tests which exhibited two‐dimensional and fracture flow behavior, (3) there is a very weak correlation between permeability and porosity, and (4) there is a lack of correlation between fracture density and both permeability and porosity.
Initial Test of a Bayesian Approach to Solar Flare Prediction
Authors: Wheatland Michael S.
Published: April 2005

A test of a new Bayesian approach to solar flare prediction is presented. The approach uses the past history of flaring together with phenomenological rules of flare statistics to make a prediction for the probability of occurrence of a large flare within an interval of time, or to refine an initial prediction (which may incorporate other information). The test of the method is based on data from the Geostationary Observational Environmental Satellites, and involves whole-Sun prediction of soft X-ray flares for 1976–2003. The results show that the method somewhat over-predicts the probability of all events above a moderate size, but performs well in predicting large events.
Neutrinos from Relativistic Outflows of Fast Spinning Magnetars
Authors: Luo Qinghuan
Published: April 2005

Pulsars may be born with a short rotation period of milliseconds with the magnetic field amplified through dynamo processes up to ∼1015–1016 G. Such millisecond magnetars spin down rapidly, emitting bursts of high-energy neutrinos and gamma rays. Specifically, acceleration of ions in both the polar gap (as in a normal pulsar) and the relativistic magnetar wind is considered. In both cases ions can be accelerated to ultra-high energies and these energetic ions can lead to production of high-energy neutrinos and gamma rays through interaction with thermal radiation from the hot neutron star or the heated inner boundary region of the stellar envelope as the result of the deposition of energy by the magnetar wind. The detectability of the neutrino flux by a kilometre-scale neutrino detector such as the planned IceCube neutrino observatory is discussed.
A Fuzzy Logic Based Algorithm for Finding Astronomical Objects in Wide-Angle Frames
Authors: Shamir Lior , Nemiroff Robert J.
Published: April 2005

Accurate automatic identification of astronomical objects in an imperfect world of non-linear wide-angle optics, imperfect optics, inaccurately pointed telescopes, and defect-ridden cameras is not always a trivial first step. In the past few years, this problem has been exacerbated by the rise of digital imaging, providing vast digital streams of astronomical images and data. In the modern age of increasing bandwidth, human identifications are many times impracticably slow. In order to perform an automatic computer-based analysis of astronomical frames, a quick and accurate identification of astronomical objects is required. Such identification must follow a rigorous transformation from topocentric celestial coordinates into image coordinates on a CCD frame. This paper presents a fuzzy logic based algorithm that estimates needed coordinate transformations in a practical setting. Using a training set of reference stars, the algorithm statically builds a fuzzy logic model. At runtime, the algorithm uses this model to associate stellar objects visible in the frames to known cataloged objects, and generates files that contain photometry information of objects visible in the frame. Use of this algorithm facilitates real-time monitoring of stars and bright transients, allowing identifications and alerts to be issued more reliably. The algorithm is being implemented by the Night Sky Live all-sky monitoring global network and has shown itself significantly more reliable than the previously used non-fuzzy logic algorithm.
Creole English Speakers’ Treatment of Tense‐Aspect Morphology in English Interlanguage Written Discourse
Authors: Clachar Arlene
Published: April 2005

The study sought to examine the effect of lexical aspect and narrative discourse structure on the pattern of acquisition and use of English verbal morphology exhibited by creole‐speaking students. Findings indicated that the emergent pattern of morphology in the creole participants’ written interlanguage appeared to be influenced not only by lexical aspect and narrative discourse, but also by a conglomerate of other factors such as the morphosyntactic features of the creoles, the blurring of the distinction between the linguistic system of English‐based creoles and that of the standard English varieties, and the constant bidirectional shifting between the creoles and the standard varieties along the creole continuum, as well as the structure of narrative discourse in creole cultures.
The Effectiveness of Empowering In‐Service Training Programs for Foreign Nurse Aides in Community‐Based Long‐Term Care Facilities
Authors: Li‐yu Wu , Yin Teresa J.C. , I‐chuan Li
Published: April 2005

Abstract  The objective of the study was to examine the effectiveness of empowering in‐service training programs for foreign nurse aides working in community‐based long‐term care (LTC) facilities. The design was a pretest and post‐test design with experiment and control groups. The sample consisted of purposeful sampling from 10 LTC facilities in the Shihlin and Peitou areas of Taipei. A total of 35 foreign nurse aides participated in this study; 16 in the experimental group and 19 in the control group. The experimental group attended the training program for a 3‐month period, whereas the control group did not receive any training. The research findings reveal that the training program was effective in increasing the work stress of workload/scheduling (Z = 2.01, p ≤ 0.05), meaning that the training program has raised the awareness of work stress for foreign nurse aides. The results could be used as a reference when considering the development of in‐service training programs in LTC facilities.
Involvement of urokinase‐type plasminogen activator in sphingosylphosphorylcholine‐induced angiogenesis
Authors: Piao Yong‐Jun , Lee Chang‐Hi , Zhu Ming Ji , Kye Kyung‐Chae , Kim Jin‐Man , Seo Young‐Joon , Suhr Ki‐Beom , Park Jang‐Kyu , Kim Chang Deok , Lee Jeung‐Hoon
Published: April 2005

Abstract:  Sphingosylphosphorylcholine (SPC) has been shown to accelerate wound healing. As angiogenesis is fundamental to proper wound healing, we examined the effect of SPC on angiogenesis using a well‐established rat aortic ring assay. SPC significantly stimulated the sprouting of endothelial cells from rat aortic ring. Recognizing its potential effect on angiogenesis, we further investigated the action of SPC using human umbilical vein endothelial cells (HUVECs) cultured in vitro. SPC significantly accelerated the closure of in vitro wound. In addition, SPC markedly enhanced the chemotactic migration and capillary‐like tube formation. Subsequently, we examined whether SPC affected the production of urokinase‐type plasminogen activator (uPA), an important regulator of angiogenesis, and found that SPC stimulated the expression of uPA at both the transcriptional and translational levels. Consistent with these results, SPC increased the activity of cell‐surface‐associated plasminogen activator. Pretreatment with antiuPA antibody significantly diminished both the chemotactic migration and capillary‐like tube formation, indicating the potential importance of uPA in SPC‐induced angiogenesis. Together, these results suggest that SPC may affect angiogenesis in the wound‐healing process via regulation of uPA production.
29Si MAS NMR Study of Dicalcium Silicate: The Structural Influence of Sulfate and Alumina Stabilizers
Authors: Bonafous Laurent , Bessada Catherine , Massiot Dominique , Coutures Jean‐Pierre , Holland Bruno Le , Colombet Pierre
Published: April 2005

The effect on β‐C2S of two stabilizing agents, calcium sulfate and alumina, has been investigated using high‐resolution 29Si solid state NMR spectroscopy. Syntheses were achieved via the gel route, wet or dry processes. Room‐temperature NMR spectra characteristics were analyzed as a function of the sintering temperature. The incorporation of Al3+ and S6+ ions, which finds expression in a noticeable line broadening, is shown to be effective above 1200°C. The 29Si chemical shift is unchanged upon doping, suggesting a mean SiO4 tetrahedra geometry identical to that in pure β‐C2S. General trends on the structure adopted by C2S upon Al3+ and S6+ doping are also discussed.
Time‐Dependent Strength Degradation of a Siliconized Silicon Carbide Determined by Dynamic Fatigue
Authors: Breder Kristin
Published: April 2005

Both fast‐fracture strength and strength as a function of stressing rate at room temperature, 1100°, and 1400°C were measured for a siliconized SiC. The fast‐fracture strength increased slightly from 386 MPa at room temperature to 424 MPa at 1100°C and then dropped to 308 MPa at 1400°C. The Weibull moduli at room temperature and 1100°C were 10.8 and 7.8, respectively, whereas, at 1400°C, the Weibull modulus was 2.8. The very low Weibull modulus at 1400°C was due to the existence of two exclusive flaw populations with very different characteristic strengths. The data were reanalyzed using two exclusive flaw populations. The ceramic showed no slow crack growth (SCG), as measured by dynamic fatigue at 1100°C, but, at 1400°C, an SCG parameter, n, of 15.5 was measured. Fractography showed SCG zones consisting of cracks grown out from silicon‐rich areas. Time‐to‐failure predictions at given levels of failure probabilities were performed.
Microstructure and Compressive Strength of SiC‐Platelet‐Reinforced Borosilicate Composites
Authors: Verma Avinash R. B. , Murthy Varanasi S. R. , Murty Gollapudi S.
Published: April 2005

The microstructure and compressive strength of SiC‐platelet‐reinforced borosilicate composites have been examined in this study. During sintering, following cold compaction, borosilicate glass crystallized into cristobalite, and the thermal expansion mismatch between the parent glass and the crystallized phase led to extensive microcracking of the matrix. Cristobalite growth (hence cracking) could be suppressed to some extent by opting for a rapid hot‐pressing cycle. Composites fabricated with various volume fractions of SiC platelets were tested in compression. A maximum compressive strength of 510 MPa was observed at 40 vol % of platelets. Further, the compressive flow behavior of these composites has been explored in the vicinity of the glass transition temperature. At temperatures above 625°C, borosilicate glass and its composites exhibited Newtonian viscous flow characteristics. Their flow stress at a given strain rate is, however, seen to increase with increasing volume fraction of SiC platelets.
Should dying patients be monitored? A reflective analysis of a critical incident
Authors: Mulligan Alison
Published: April 2005

•The aim of the article is to highlight, through reflection, important aspects of caring for a dying patient in an intensive care unit

•A review of current literature surrounding the monitoring of dying patients

•Responsibilities and roles of intensive care nurses when caring for dying patients

•Recommendations for a change in practice to reflect the Literature
AtXTH27 plays an essential role in cell wall modification during the development of tracheary elements
Authors: Matsui Akihiro , Yokoyama Ryusuke , Seki Motoaki , Ito Takuya , Shinozaki Kazuo , Takahashi Taku , Komeda Yoshibumi , Nishitani Kazuhiko
Published: April 2005

Xyloglucan endotransglucosylases/hydrolases (XTHs) are a class of enzymes capable of catalyzing the molecular grafting between xyloglucans and/or the endotype hydrolysis of a xyloglucan molecule. They are encoded by 33 genes in Arabidopsis. Whereas recent studies have revealed temporally and spatially specific expression profiles for individual members of this family in plants, their biological roles are still to be clarified. To identify the role of each member of this gene family, we examined phenotypes of mutants in which each of the Arabidopsis XTH genes was disrupted. This was undertaken using a reverse genetic approach, and disclosed two loss‐of‐function mutants for the AtXTH27 gene, xth27‐1 and xth27‐2. These exhibited short‐shaped tracheary elements in tertiary veins, and reduced the number of tertiary veins in the first leaf. In mature rosette leaves of the mutant, yellow lesion‐mimic spots were also observed. Upon genetic complementation by introducing the wild‐type XTH27 gene into xth27‐1 mutant plants, the number of tertiary veins was restored, and the lesions disappeared completely. Extensive expression of the pXTH27::GUS fusion gene was observed in immature tracheary elements in the rosette leaves. The highest level of AtXTH27 mRNA expression in the rosette leaves was observed during leaf expansion, when the tracheary elements were elongating. These findings indicate that AtXTH27 plays an essential role during the generation of tracheary elements in the rosette leaves of Arabidopsis.
Primary care nurses using guidelines in Thailand: a randomized controlled trial
Authors: Pagaiya Nonglak , Garner Paul
Published: April 2005

Background  Nurses run primary health centres in Thailand. We examined whether clinical guidelines improved the quality of the care they provide.

Methods  Eighteen nurse‐led health centres randomized to (a) guidelines, receiving a training workshop plus educational outreach visit, with guidelines for children (acute respiratory tract infection and diarrhoea) and adults (diazepam prescribing and diabetes management) or (b) usual care. Outcomes were changes at 6 months in antibiotic use, diazepam prescribing, drug costs per patient, and a composite process index for diabetes care.

Results  Baseline prescribing was high for antibiotics (37% of all attendees), and no difference between intervention and control sites was detected at follow‐up for this variable. In children (0–5 years old), antibiotics were widely used for acute respiratory tract infection (34%), and fell with guidelines (intervention: 42% at baseline to 27% at follow‐up; control: 27–30%, P = 0.022), with an associated fall in drug costs per patient. Antibiotics were widely prescribed for diarrhoea in children (91%), but no change was detected with guidelines. In adults, diazepam prescribing at baseline was high (17%), and fell in the guidelines group (intervention: 17–10%; control 21–18%; P = 0.029). Diabetes care was generally good, and changed little with guidelines.

Conclusion  Staff at primary health centres over‐prescribe antibiotics in children and tranquilizer in adults. Clinical guidelines implemented with workshops and educational outreach visits improved some but not all aspects of prescribing in the short‐term.
Evaluation of antiretroviral therapy results in a resource‐poor setting in Blantyre, Malawi
Authors: Van Oosterhout Joep J. , Bodasing Neena , Kumwenda Johnstone J. , Nyirenda Cooper , Mallewa Jane , Cleary Paul R. , De Baar Michel P. , Schuurman Rob , Burger David M. , Zijlstra Eduard E.
Published: April 2005

Objective  To evaluate treatment results of the paying antiretroviral therapy (ART) clinic of Queen Elizabeth Central Hospital, a large public and teaching hospital in Blantyre, Malawi. The only ART was a fixed drug combination of stavudine, lamivudine and nevirapine.

Methods  Cross sectional study with interviews, laboratory tests (CD4 count, viral load, nevirapine plasma levels, transaminases) and data extraction from files.

Results  A total of 422 (59%) of the patients who started ART since 2000 were lost to follow‐up. The 176 patients enrolled in the study had good virological and excellent clinical treatment results. The most common side effect was peripheral neuropathy. Nevirapine plasma levels were remarkably high and associated with successful virological treatment results. Two simple adherence questions pertaining to the use of medication in the previous 8 days corresponded well with nevirapine levels. The most important reasons for non‐adherence were shortage of drugs in the hospital pharmacy and personal financial constraints.

Conclusions  (1) Many patients were lost to follow‐up. (2) High nevirapine levels contributed to good therapy results in those studied. (3) Simple adherence questions predicted subtherapeutic nevirapine levels. (4) Antiretroviral drug supply needs to be uninterrupted and free of charge, to prevent avoidable non‐adherence.
Limits to the estimation of species richness: The use of relative abundance distributions
Authors: Ulrich Werner , Ollik Marcin
Published: April 2005

The present study demonstrates the possibility of estimating species numbers of animal or plant communities from samples using relative abundance distributions. We use log‐abundance–species‐rank order plots and derive two new estimators that are based on log‐series and lognormal distributions. At small to moderate sample sizes these estimators appear to be more precise than previous parametric and nonparametric estimators. We test our estimators using samples from 171 published medium‐sized to large animal and plant communities taken from the literature. By this we show that our new estimators define also limits of precision.
Informed choice and public health screening for children: the case of blood spot screening
Authors: Hargreaves Katrina M. , Stewart Ruth J. , Oliver Sandy R.
Published: April 2005

Objective  To examine parents’ and health professionals’ views on informed choice in newborn blood spot screening, and assess information and communication needs.

Design and participants  A qualitative study involving semi‐structured telephone interviews and focus groups with 47 parents of children who were either found to be affected or unaffected by the screened conditions, and 35 health professionals with differing roles in newborn blood spot screening programmes across the UK.

Results and conclusions  Parents and health professionals recognize a tension between informed choice in newborn blood spot screening and public health screening for children. Some propose resolving this tension with more information and better communication, and some with rigorous dissent procedures. This paper argues that neither extensive parent information, nor a signed dissent model adequately address this tension. Instead, clear, brief and accurate parent information and effective communication between health professionals and parents, which take into account parents’ information needs, are required, if informed choice and public health screening for children are to coexist successfully.
A DOOYEWEERD‐BASED APPROACH TO REGIONAL ECONOMIC DEVELOPMENT
Authors: AAY HENK , VAN LANGEVELDE AB
Published: April 2005

Within regional science there is a need for a general theory of regional economic development, one that evaluates and integrates existing approaches. In this paper, the philosophy of Herman Dooyeweerd is used as a basis for conceptualising the contours of such a theory. Contributions of this philosophy especially relevant for regional economic development are functional pluralism and non‐reductionism, interweaving among entities, a broad understanding of the human person and built‐in normativity. While all the aspects are significant in regional economic development, the spatial aspect is singled out for particular attention. Dooyeweerd's philosophy is able to incorporate existing approaches to regional economic development though not without criticising and revising them.
An historical examination of the concept of jiga (ego) in Japanese psychology, particularly as employed in a dissertation by Yujiro Motora and in Ladd's psychological theory
Authors: SUZUKI YUKO
Published: April 2005

Abstract:  The translation of the terms “ego” as jiga, “self” as jiko, and “self‐consciousness” as jiko‐ishiki, has become standard in Japan. However, other Japanese words have been used for these terms in the past. For example, in the first English‐Japanese Dictionary of Philosophy, Tetsugaku jii, (Inoue, 1881), “ego” is translated as ga or jiko, and the term jiga does not occur in the dictionary, despite its use as early as the 16th century. The main aim of the present paper is to analyze the conceptual variations that have been attached to the Japanese term jiga. Under the influence of psychoanalytical ego psychology, and Erikson in particular, jiga now has the specific meaning of “ego” in Japan. This ignores the cross‐cultural perspective, for it is well‐accepted that the psychology of Westerners and of Japanese is very different, and this implies that the concept of ego should not be uncritically adopted from the West. Analyses of Yujiro Motora's English dissertation, “Exchange,” of the late 19th century (Motora, 1888), and of G.T. Ladd's original and translated work reveal what Japanese psychologists meant when using the terms ego, jiga, and jiko.