bluuebunny/crossref_metadata_2025 huggingface dataset:
Solution NMR structure of the SH3 domain of human nephrocystin and analysis of a mutation‐causing juvenile nephronophthisis
Authors: le Maire Albane , Weber Thomas , Saunier Sophie , Broutin Isabelle , Antignac Corinne , Ducruix Arnaud , Dardel Frédéric
Published: February 2005

Human nephrocystin is a protein associated with juvenile NPH, an autosomal recessive, inherited kidney disease responsible for chronic renal failure in children. It contains an SH3 domain involved in signaling pathways controlling cell adhesion and cytoskeleton organization. The solution structure of this domain was solved by triple resonance NMR spectroscopy. Within the core, the structure is similar to those previously reported for other SH3 domains but exhibits a number of specific noncanonical features within the polyproline ligand binding site. Some of the key conserved residues are missing, and the N‐Src loop exhibits an unusual twisted geometry, which results in a narrowing of the binding groove. This is induced by the replacement of a conserved Asp, Asn, or Glu residue by a Pro at one side of the N‐Src loop. A systematic survey of other SH3 domains also containing a Pro at this position reveals that most of them belong to proteins involved in cell adhesion or motility. A variant of this domain, which carries a point mutation causing NPH, was also analyzed. This change, L180P, although it corresponds to a nonconserved and solvent‐exposed position, causes a complete loss of the tertiary structure. Similar effects are also observed with the L180A variant. This could be a context‐dependent effect resulting from an interaction between neighboring charged side‐chains. Proteins 2005. © 2005 Wiley‐Liss, Inc.
Dependence of magnetic properties on the growth conditions of MnGaN grown by rf N plasma molecular beam epitaxy
Authors: Haider Muhammad B. , Constantin Costel , Al‐Brithen Hamad , Caruntu Gabriel , O'Connor Charles J. , Smith Arthur R.
Published: February 2005

MnGaN has been grown by radio frequency N plasma‐assisted molecular beam epitaxy. MnGaN samples were grown on MOCVD GaN(0001)/sapphire(0001) at substrate temperature of 550 °C under different Ga/N flux ratios leading to 4 different growth regimes: N‐rich, slight metal‐rich, metal‐rich, and Ga‐rich. It is found that in the case of MnGaN, Mn incorporation and hence magnetic properties clearly depend on the growth conditions. Briefly, it is found that the N‐rich conditions give a sample with much larger magnetization compared to the other samples. Slight metal‐rich and metal‐rich grown samples have very little magnetization. Finally, Ga‐rich grown samples have intermediate level of magnetization. Possible origins of the magnetization are discussed. Ga‐rich magnetization is attributed to accumulates, but N‐rich magnetization is attributed to carrier‐mediated ferromagnetism and/or ferromagnetism due to clusters. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Grazing‐incidence diffraction strain analysis of a laterally patterned Si wafer treated by focused Ge and Au ion beam implantation
Authors: Grenzer J. , Pietsch U. , Bischoff L.
Published: February 2005

Strain analysis of a laterally patterned Si‐wafer was carried out utilizing X‐ray grazing‐incidence diffraction with synchrotron radiation. The lateral patterning was done by focused ion beam implantation using an ion source of liquid AuGeSi alloy. Samples were prepared by either 35 keV Au+ ions (dose: 0.2, 2 × 1014 cm–2) or 70 keV Ge++ ions (dose: 8 × 1014 cm–2). It was shown that due to implantation a periodical defect structure is created consisting of both implanted and not implanted stripes. The evaluated depth distribution of defects within the implanted stripes corresponds to that obtained by TRIM calculation. The induced strain distribution, however, shows no periodicity. This can be explained by an overlap of the strain fields created in each implanted stripe. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetic properties of Cu substituted NdMn2Si2 intermetallics
Authors: Elmali A. , Dincer I. , Elerman Y. , Ehrenberg H. , Fuess H.
Published: February 2005

The structure and magnetic properties of NdMn2–xCuxSi2 (0.2 ≤ x ≤ 1) were studied by X‐ray powder diffraction and magnetization measurements. In this study, we investigate the variations in the magnetic properties of NdMn2–xCuxSi2 as a function of Cu concentration by examing the evolution of the features in the temperature dependence of the magnetization. Earlier neutron diffraction experiments showed that the ferromagnetic Mn planes are ordered antiparallel along the c‐axis below 380 K and the Nd sublattice orders at 33 K in NdMn2Si2. The ordering of the Nd sublattice reconfigures the ordering in Mn sublattice and leads to ferromagnetic ordering. With increasing amount of Cu, the Curie temperature has a maximum value of 120 K at x = 0.7 and decreases for the samples with x ≥ 0.8. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Advances in photoreflectance characterisation of photonic (resonant‐cavity) and transistor epiwafers
Authors: Murtagh M. E. , Ward S. , Kelly P. V.
Published: February 2005

Advances in the application of non‐contact photoreflectance (PR) spectroscopy to the characterisation of epiwafer device materials are presented. The study examines both vertical cavity surface emitting laser (VCSEL) and heterojunction bipolar transistor (HBTs) device structures. Emphasis is placed on the technologically important applications of VCSEL device material characterisation, for which PR offers the only true non‐destructive testing capability, as well as upon the measurement of electric fields in device epiwafers for rf application transistors such as HBTs. This paper demonstrates the application of non‐destructive and rapid techniques for evaluation and control of compound semiconductor materials for both VCSEL and HBT technology. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Control of Al‐doping in 4H–SiC homo‐epitaxial layers grown with a HMDS/TMA/P mixture
Authors: Sartel C. , Soulière V. , Zielinski M. , Monteil Y. , Camassel J. , Smith L. , Rushworth S.
Published: February 2005

We report on the growth of thin, aluminium doped, homo‐epitaxial layers of 4H–SiC using a threefold mixture of purified hexamethyldisilane (HMDS) admixted with propane (P) and trimethylaluminium (TMA). The growth has been performed in an AP‐CVD, cold wall, vertical reactor in which the growth of 4H–SiC layers using HMDS admixed with propane has been well demonstrated. To control, as a function of the growth parameters, the amount of aluminium incorporated in the epitaxial layers SIMS, C(V) and Raman experiments were done. They show that good quality p‐type epitaxial layers can be grown, up to a final aluminium concentration of about 2 × 1019 at cm–3. Comparing with the more standard gas system silane/TMA/P, we have found that there is no significant difference. The total amount of Al incorporated is about the same and, in both cases, the incorporation starts to be limited when the growth temperature reaches 1500 °C. In both cases, also, the C/Si ratio and the growth rate influence the aluminium concentration. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Control of epitaxial layers grown on 4H–SiC: from 3C microcrystalline inclusions to type II quantum well structures
Authors: Juillaguet S. , Balloud C. , Soulière V. , Sartel C. , Camassel J. , Y. Monteil
Published: February 2005

We report the results of a series of LTPL (Low Temperature PhotoLuminescence) investigation performed on n‐type, non‐intentionally doped, 4H–SiC samples. We focus on the defect structure introduced by a growth fault in the stacking sequence. We treat the fault as a 3C quantum well embedded in a 4H–SiC matrix and use a simple 2‐dimensional approximation to deduce the extent of the lattice perturbation associated with a given defect. We show that the intrinsic type‐II nature of the band alignment, combined with the effect of the spontaneous polarization, must result in a double bound‐exciton signature per well, which is resolved for the first time. The comparison with experimental results confirms also that, after a relatively small critical layer thickness, the back conversion from cubic to hexagonal remains an unsolved problem. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A method for quantitative determination of deuterium content in biological material
Authors: He Yihui , Tang Caihua , Mao Jiangsen , Liu Ziyang , Huang Weixing , Mao Zi'an
Published: February 2005

A method was developed for quantitative determination of deuterium incorporated into live organisms or biological macromolecules. The deuterated biological material was mixed with a bovine serum albumin (BSA) supporter to make a homogeneous sample for which the δD value (vs. VSMOW) was analyzed using a dual‐inlet gas isotope mass spectrometer. The method is described in detail, and the equation for calculation of deuterium content is presented, i.e., C = 1/500 × k × RVSMOW × C × 106 ppm. Deuterated hepatitis A virus (HAV) RNA and BSA were systematically investigated. The results demonstrate that the method is capable of direct measurement of deuterium content, and is highly repeatable and reliable with a standard deviation of ±3‰. It is stressed that the quantity of deuterated sample required is extremely small as a result of using BSA as supporter. The method may be applied in many fields, and has the strengths of simplicity, relative cheapness, and robustness. Copyright © 2005 John Wiley & Sons, Ltd.
Hardware‐accelerated protein identification for mass spectrometry
Authors: Alex Anish T. , Dumontier Michel , Rose Jonathan S. , Hogue Christopher W. V.
Published: February 2005

An ongoing issue in mass spectrometry is the time it takes to search DNA sequences with MS/MS peptide fragments (see, e.g., Choudary et al., Proteomics 2001; 1: 651–667.) Search times are far longer than spectra acquisition time, and parallelization of search software on clusters requires doubling the size of a conventional computing cluster to cut the search time in half. Field programmable gate arrays (FPGAs) are used to create hardware‐accelerated algorithms that reduce operating costs and improve search speed compared to large clusters. We present a novel hardware design that takes full spectra and computes 6‐frame translation word searches on DNA databases at a rate of approximately 3 billion base pairs per second, with queries of up to 10 amino acids in length and arbitrary wildcard positions. Hardware post‐processing identifies in silico tryptic peptides and scores them using a variety of techniques including mass frequency expected values. With faster FPGAs protein identifications from the human genome can be achieved in less than a second, and this makes it an ideal solution for a number of proteome‐scale applications. Copyright © 2005 John Wiley & Sons, Ltd.
Characterization of NiB amorphous alloys with x‐ray photoelectron and secondary ion mass spectroscopy
Authors: Diplas S. , Lehrmann J. , Jørgensen S. , Våland T. , Watts J. F. , Taftø J.
Published: February 2005

Amorphous NiB alloys with nominal compositions 30 at.% B and 50 at.% B were produced via electrodeposition on pure Ni polycrystalline substrates. The surfaces of the alloys were characterized with x‐ray photoelectron spectroscopy (XPS) and dynamic secondary ion mass spectrometry (DSIMS). Information on the compositional variation with depth was acquired with XPS both non‐destructively, in angle‐resolved mode (ARXPS), and destructively with argon ion etching, as well as with DSIMS. Boron oxide dominates the outermost surface of the alloys. Its presence also in the bulk of the alloys is attributed to oxidation during processing, whereas the presence of hydrogen detected with SIMS is attributed to adsorption occurring during processing. The Auger parameter concept and information from the primary and secondary structure of the XPS spectrum were employed to probe the electronic changes occurring upon alloying. It is suggested that the main electronic changes occurring are hybridization of the Ni spd states with the B sp states and an apparent increase of the electron density around the Ni sites. Copyright © 2005 John Wiley & Sons, Ltd.
Adsorption and orientation kinetics of self‐assembled films of octadecyltrimethoxysilane on aluminium oxide surfaces
Authors: Thomsen Lars , Watts Benjamin , Cotton Daniel V. , Quinton Jamie S. , Dastoor Paul C.
Published: February 2005

X‐ray photoelectron spectroscopy (XPS) and near‐edge x‐ray absorption fine structure (NEXAFS) spectroscopy have been used to study the time‐dependent adsorption and molecular orientation behaviour of octadecyltrimethoxysilane (ODTMS) on native aluminium oxide surfaces. By measuring the adsorption isotherm using XPS, we show that ODTMS molecules exhibit oscillatory adsorption. The oscillatory adsorption behaviour for ODTMS is analogous to that observed for its simpler short‐chain ‘cousin’—propyltrimethoxysilane (PTMS)—and suggests that the length of the functional alkyl chain on an organosilane does not have a significant influence upon the oscillatory adsorption mechanism. The oscillation in the ODTMS adsorption isotherm shows a maximum and a minimum in coverage at an adsorption time of ∼30 and ∼65 s, respectively, for a 0.75% ODTMS solution in a 90% ethanol–10% water mixture at pH 4. The time‐dependent orientation behaviour of the ODTMS molecules during adsorption was examined using angular‐dependent carbon K‐edge NEXAFS spectroscopy. We show that the alignment of the ODTMS film changes systematically with deposition time and appears to be correlated with coverage measurements obtained using XPS. In particular, by combining the XPS and NEXAFS results we demonstrate that the minimum ODTMS coverage corresponds to a film whose alignment appears to be predominantly randomized. Copyright © 2005 John Wiley & Sons, Ltd.
XPS imaging investigations of pitting corrosion mechanisms in Inconel 600
Authors: Kobe B. A. , Ramamurthy S. , Biesinger M. C. , McIntyre N. S. , Brennenstühl A. M.
Published: February 2005

The surface chemistry associated with pitting corrosion on a nickel‐based alloy, Inconel 600, has been studied using imaging x‐ray photoelectron spectroscopy. The irregularity of the sample surfaces necessitated a more elaborate background correction than is usually applied in such imaging. Areas of active pitting were found to contain corrosion products that are high in chromium oxide and depleted in nickel and iron. Sites of anodic activity on the surface were able to be defined more clearly using principal component analysis. Elements that are dissolved preferentially are deposited cathodically within well‐defined regions whose distance from the anodic pit appears related to the open‐circuit potential. Copyright © 2005 John Wiley & Sons, Ltd.
Possible mechanism for the inhibition of lectin-erythrocyte interaction in presence of endogenous lectin receptor
Authors: Basu Prabnab S. , Datta Pradip K. , Datta Tapash K.
Published: February 2005

The presence of hydrophobic sites in the lectin-I molecule was indicated by hydrophobic probes like 1-anilinonapthalene-8-sulfonic acid (ANS), 2-p-toluidinyl napthalene-6-sulfonic acid (TNS), N-phenyl-1-napthylamine (NA) and rose bengal (RB). This was further confirmed by amino acid modifications in the hydrophobic region of the lectin-I molecule. The binding of ANS, TNS, NA and RB to lectin-I was affected in the presence of NaCl. The involvement of hydrophobic interactions in rice-bean lectin-I-endogenous lectin receptor (ELR) complex were indicated by alterations in the circular dichroism and fluorescence emission spectra. The percentage of β-conformation (55–63%) of lectin-I was decreased by addition of ELR. ELR on reacting with lectin-I reduced the fluorescence emissions of the hydrophobic probes while fluorescence emission of ANS, TNS, NA and RB were greatly enhanced in presence of lectin-I alone. N-aceyl-galactosamine did not change the fluorescence emissions of any of the hydrophobic probes in presence or in absence of lectin-I. This demonstrates that carbohydrate and hydrophobic sites may be different and non-interacting. It is proposed that the ELR in reacting with lectin-I, induced conformational changes in the lectin-I molecule and thereby affected its erythroagglutinating activity with human blood group “A” erythrocytes.
Proton-lactate co transport in basolateral membrane vesicles from rat jejunum
Authors: Orsenigo Maria Novella , Tosco Marisa , Laforenza Umberto , Faelli Alide
Published: February 2005

Proton-coupled lactate transport across the basolateral membrane of rat jejunal enterocyte was studied using well purified membrane vesicles. L-lactate uptake is stimulated by an inwardly directed H+ gradient; the effect of the pH difference is drastically reduced by FCCP and by pCMBS; unlabelled L-lactate causes a strong inhibition, whilst furosemide is uneffective. The H+ gradient-dependent stimulation of L-lactate uptake is significantly inhibited also by SCN−: this finding could explain results recently reported in the literature in which H+-lactate symport was not evidenced in basolateral membranes from rat jejunum.
The influence of Methylprednisolone on the energy metabolism of Ehrlich ascites tumour cells
Authors: Buttgereit Frank , Müller Marianne , Wolbart Karsten , Thiele Bernhard , Hiepe Falk
Published: February 2005

Using Ehrlich ascites tumour cells, the short-term effects of the therapeutic glucocorticoid Methylprednisolone (MP) on the cellular energy metabolism were studied. ATP-consuming processes involved in the rapid MP effects were identified indirectly from the effects of MP on cellular oxygen consumption related to the inhibition of respiration by selective inhibitors of Ca2+-ATPase and protein synthesis. The effects of MP on plasma membrane permeability for Ca2+ ions and phospholipid turnover were studied directly by using confocal laser scanning microscopy and tracerkinetic measurements, respectively. MP inhibited cellular oxygen consumption, suppressed the inhibitory effect of lanthanum but not that of cycloheximide on oxygen consumption, blocked the [Ca2+]i rise in response to calcium ionophore A 23187, and decreased phospholipid turnover. MP acted instantly in a dose-dependent manner.

The observed effects of MP are discussed in relation to the hypothesis that the drug has direct membrane effect affecting plasma membrane permeability and function.
Cholesterol enhances cationic liposome-mediated DNA transfection of human respiratory epithelial cells
Authors: Bennett Michael J. , Nantz Michael H. , Balasubramaniam Rajiv P. , Gruenert Dieter C. , Malone Robert W.
Published: February 2005

Cationic liposome transfection reagents are useful for transferring polynucleotides into cells, and have been proposed for human pulmonary gene therapy. The effect of adding cholesterol to cationic lipid preparations has been tested by first formulating the cationic lipid N-[1-(2,3-dioleoyloxy)propyl-N-[1-(2-hydroxy)ethyl]-N,N-dimethyl ammonium iodide (DORI) with varying amounts of dioleoylphos-phatidylethanolamine (DOPE) and cholesterol. Cholesterol was found to enhance lipid-mediated transfection in both the respiratory epithelial cells and mouse fibroblasts. These findings will facilitate nucleic acid transfection of many cell types including differentiated epithelial cell monolayers, and therefore may be useful for examining gene regulation in various cell types and for developing pulmonary gene therapy.
Zn2+ inhibits the anion transport activity of Band 3 by binding to its cytoplasmic tail
Authors: Tu Y. P. , Xu H.
Published: February 2005

Zn2+ can induce a conformational change of Band 3 with concomitant inhibition of its anion transport activity of human erythrocyte membrane vesicles only from the cytoplasmic side. The Zn2+ inhibition exhibits a dose-dependent manner with an apparent half maximal concentration of 50 μM ZnCl2 and can be reversed by 0.5 mM EDTA, but not by 1 mM dithiothreitol. The Zn2+ effect is specific and no similar inhibitory action could be observed by other divalent cations (Cu2+, Mn2+, Mg2+ or Sr2+).
Role of cell membrane Na,K-ATPase for survival of human lymphocytes in vitro
Authors: Falciola Jacques , Volet Bernard , Anner Rolf M. , Moosmayer Marlis , Lacotte Danielle , Anner Beatrice M.
Published: February 2005

Lymphocytes are primordial immune cells with variable life times. Besides genetic programming, extracellular factors interacting with cell surface receptors might alter cell survival. We investigated whether the activity of the membrane-embedded Na,K-ATPase (EC 3.6.1.37) or sodium pump (NKA) plays a role for cell survival since this ubiquitous system establishes the vital transmembrane Na and K gradients as well as the resulting high intracellular K/Na ratio required for macromolecule synthesis; furthermore, the system exposes an extracellular inhibitory receptors for cardioactive steroids and palytoxin. Isolated human lymphocytes were incubated in vitro and their viability assessed by exclusion of trypan blue. Various incubation conditions were compared; in RPMI-1640 medium cell viability was preserved for 30 h at 37 °C. Externally added ouabain, a hydrophilic cardioactive steroid, blocked the [86Rb]potassium uptake at nanomolar concentrations. Despite pump inhibition ouabain did not alter lymphocyte survival, even at 10 mM for 30 h. By contrast, the hydrophilic toxin palytoxin, the most potent animal poison described so far, killed all cells within 2 h at 10 nM; this toxin is known to act via the sodium pump and to provoke deadly cation-leaks by unmasking a channel component. Intracellular Na increased and K decreased as measured by atomic absorption spectrometry in presence of palytoxin; cell swelling was seen by electron microscopy. Ouabain protected the cells from the toxic effect of palytoxin. The results reveal a pivotal role of NKA integrity for lymphocyte survival.
Coxsackievirus B3 entry into the host cell interferes with G-protein-mediated transmembrane signalling
Authors: Novotny Jiri , Kvapil Petr , Cello Jeronimo , Ransnäs Lennart A.
Published: February 2005

In the present work we used various cell lines in order to study the possible effect of coxsackievirus B3 (CVB3) entry on the adenylyl cyclase transmembrane signalling system. A significant decrease (by about 10–20%) was found in forskolin-augmented as well as in AlF4−- and GTPγS-sensitive adenylyl cyclase activity in plasma membranes isolated from HeLa, HEp-2, Vero and green monkey kidney cells shortly (up to 60 min) preincubated with CVB3 (5 PFU/cell). Moreover, the ability of G-proteins derived from plasma membranes of infected cells to reconstitute AC activity in the cyc− mutant of S49 cells was also reduced. Content of G-protein subunits, however, remained unchanged after CVB3 attachment. Functional alterations in the G-protein-mediated adenylyl cyclase signalling system were accompanied by a marked decrease (by about 20–40%) of intracellular cAMP levels in virus-affected cells. These findings demonstrate clearly that CVB3 may affect functioning of the G-protein regulated adenylyl cyclase transmembrane signalling system in virus-sensitive cells as early as during the first period of its contact with the cellular plasma membrane.
Signal transduction and motility of Dictyostelium
Authors: Newell Peter C.
Published: February 2005

This review is concerned with the roles of cyclic GMP and Ca2+ ions in signal transduction for chemotaxis of Dictyostelium. These molecules are involved in signalling between the cell surface cyclic AMP receptors and cytoskeletal myosin II involved in chemotactic cell movement. Evidence is presented for uptake and/or eflux of Ca2+ being regulated by cyclic GMP. The link between Ca2+, cyclic GMP and chemotactic cell movement has been explored using “streamer F” mutants whose primary defect is in the structural gene for the cyclic GMP-specific phosphodiesterase. This mutation causes the mutants to produce an abnormally prolonged peak of cyclic GMP accumulation in response to stimulation with the chemoattractant cyclic AMP. The production and relay of cyclic AMP signals is normal in these mutants, but certain events associated with movement are (like the cyclic GMP response) abnormally prolonged in the mutants. These events include Ca2+ uptake, myosin II association with the cytoskeleton and regulation of both myosin heavy and light chain phosphorylation. These changes can be correlated with changes in the shape of the amoebae after chemotactic stimulation. Other mutants in which the accumulation of cyclic GMP in response to cyclic AMP stimulation was absent produced no myosin II responses.

A model is described in which cyclic GMP (directly or indirectly via Ca2+) regulates accumulation of myosin II on the cytoskeleton by regulating phosphorylation of the myosin heavy and light chain kinases.
Vaccination today and tomorrow
Authors: Brown F.
Published: February 2005

The vaccines against infectious diseases in use today are, with few exceptions, prepared from the causal agents themselves, either by inactivating them with a chemical such as formaldehyde or by attenuating them so that they grow and thus evoke an immune response in the natural host but cause no disease. These empirical approaches have produced many highly successful vaccines. Increasing knowledge at the molecular level of the agents and of the immune response to protein antigent is now providing us with the opportunity to design vaccines that will elicit protective responses without the need to use the agents themselves. The critical issue is to identify the immune responses that correlate with protection.
Novel actions of ryanodine and analogues—Perturbers of potassium channels
Authors: Vais H. , Usherwood P. N. R.
Published: February 2005

The effects of ryanodine, 9,21-didehydroryanodine and 9,21-didehydroryanodol on two types of K+ channel (a maxi, Ca2+-activated, 170 pS channel (BK channel) and an inward rectifier, stretch-sensitive channel of 35 pS conductance (IK channel) found in the plasma membrane of locust skeletal muscle have been investigated. 10−9M-10−5M ryanodine irreversibly induced a dose-dependent reduction of the reversal potential (Vrev) of the currents of both channels, i.e. from ~60 mV in the absence of the alkaloid to ~15 mV for 10−5M ryanodine, measured under physiologically normal K+ and Na+ gradients. In both cases the change in the ionic selectivity was Ca2+-independent. 9,21-didehydroryanodine and 9,21-didehyroryanodol also reduced Vrev, but only to ~35 mV during application of 10−5M of these compounds. Additionally, 9,21-didehydroryanodine reversibly diminished the conductances of the two K+ channels. To test the hypothesis that ryanoids increase Na+ permeability by enlarging the K+ channels, the channels were probed with quaternary ammonium ions during ryanoid application. When applied to the cytoplasmic face of inside-out patches exised from locust muscle membrane, TEA blocked the K+ channels in a voltage-dependent fashion. The dissociation constant (Kd(0)) for TEA block of the IK channel was reduced from 44 mM to 1 mM by 10−7 M ryanodine, but the voltage-dependence of the block was unaffected. Qualitatively similar data were obtained for the BK channel. Ryanodine had no effect on the Kd for cytoplasmically-applied TMA. However, the voltage-dependence for TMA block was increased for both K+ channels, from 0.47 to ~0.8 with 10−6M ryanodine. The effects of ryanodine on TEA and TMA block support the hypothesis that ryanodine enlarges the K+ channels so as to facilitate permeation of partially hydrated Na+ ions.
Membrane pores—From biology to track-etched membranes
Authors: Bashford C. Lindsay
Published: February 2005

Flow of ions through narrow pores, either induced in biological membranes or created in synthetic membrane filters, exhibits, under appropriate conditions: 1) rapid switching of ion current between high and low conducting states; 2) selectivity between different ions; 3) inhibition by protons or divalent cations with an order of efficacy usually H+ >Zn2+>Ca2+ >Mg2+. It seems reasonable to conclude that these common properties arise from a common cause-the nature of the flow of ions close to a charged surface.
Proof systems for message-passing process algebras
Authors: Hennessy M. , Lin H.
Published: February 2005

We give sound and complete proof systems for a variety of bisimulation based equivalences over a message-passing process algebra. The process algebra is a generalisation of pure
CCS
where the actions consist of receiving and sending messages or data on communication channels; the standard prefixing operator
a.p
is replaced by the two operators
c?x.p
and
c!e.p
and in addition messages can be tested by a conditional construct. The various proof systems are parameterised on auxiliary proof systems for deciding on equalities or more general boolean identities over the expression language for data. The completeness of these proof systems are thus relative to the completeness of the auxiliary proof systems.
Invariants and closures in the theory of rewrite systems
Authors: Rönn Stefan
Published: February 2005

The article investigates some useful concepts of rewrite systems, especially invariants and closures. The concepts are formalised with so-called string expressions, for which an axiomatisation is given. The central operator in the theory of rewrite systems, the rewrite operator, is introduced with formulas that permit a calculational approach. The connections with distributed programming are also explained.
Slicing programs in the presence of errors
Authors: Harman Mark , Simpson Dan , Danicic Sebastian
Published: February 2005

Program slicing is a technique by which statements are deleted from a program in such a way as to preserve a projection of the original program's semantics. It is shown that slicing algorithms based upon traditional defined and referenced variable sets do not preserve a projection of strict semantics with respect to computations which cause errors. Rather, these approaches preserve a projection of the program's semantics which is lazy with respect to errors. A modified version of defined and referenced variable sets is introduced, which provides the freedom to choose the form of semantics to be preserved.
Structure‐based systems biology: a zoom lens for the cell
Authors: Aloy Patrick , Russell Robert B
Published: February 2005

Systems biology seeks to explain complex biological systems, such as the cell, through the integration of many different types of information. Here, we discuss how the incorporation of high‐resolution structural data can provide key molecular details often necessary to understand the complex connection between individual molecules and cell behavior. We suggest a process of zooming on the cell, from global networks through pathways to the precise atomic contacts at the interfaces of interacting proteins.
Oral versus high dose parenteral iron supplementation in pregnancy
Authors: Kumar A. , Jain S. , Singh N.P. , Singh T.
Published: February 2005

Objective

To compare the effect of daily oral iron supplementation with two injections of high dose parenteral iron.

Method

A total of 220 pregnant women with a singleton pregnancy and hemoglobin between 8 to 11 g% at 16–24 weeks gestation were identified and randomly divided into two groups. Group A was started on daily oral iron therapy of 100 mg of elemental iron. Group B was given 250 mg of iron sorbitol intramuscularly and repeated at an interval of 4–6 weeks. Blood indices were evaluated at the beginning of study and at 36 weeks to see the effect after iron supplementation in the two groups. The data were analyzed using SPSS software, version 10.1.

Results

Definitive and comparable improvement in hemoglobin and all the blood indices (hematocrit, MCH, MCHC, MCV, Serum iron and TIBC) was observed. The absolute change in hemoglobin and hematocrit was 1.18±0.68 g% and 4.02±2.59% in oral group, 1.34±0.77 g% and 4.93±3.65% in parenteral group, respectively. Serum ferritin showed statistically significant absolute rise (10.43±7.92 μg/dl) after parenteral iron supplementation as compared to oral iron supplementation (9.76±4.78 μg/dl). Obstetric outcome was comparable in two groups.

Conclusion

Two treatment regimens are biologically equivalent in terms of hematological response. Two high doses of intramuscular iron can be a good substitute to meet iron requirement in pregnancy.
ANALYSIS OF HEALTH SERVICES USE FOR RESPIRATORY ILLNESS IN INDONESIAN CHILDREN: IMPLICATIONS FOR POLICY
Authors: THIND AMARDEEP
Published: February 2005

Respiratory illness continues to be a leading cause of paediatric morbidity and mortality in Indonesia. The Indonesian government is moving towards a more managed care-based approach as it reforms its health care system following the 1997 financial crisis. In order to better design contractual relationships between the payor and different providers, there needs to be a better understanding of the patterns and predictors of health services utilization for respiratory illness. This study uses the Indonesia Demographic and Health Survey to study the determinants of private, public and non-formal provider utilization for respiratory illness. Multinomial logistic regression models for predicting use were constructed using the Andersen Behavioural Model as the conceptual framework. The findings indicate that age, household size, maternal education, religion, the asset index, location and illness severity play a role in determining use of private, public or non-formal providers. The results indicate that from a policy perspective, the Indonesian government needs be inclusive rather than exclusive in the choice of providers that are contracted by the managed care plans, in order to safeguard the health of the under-five population.
ISONYMY AND THE STRUCTURE OF THE PROVENÇAL-ITALIAN ETHNIC MINORITY
Authors: BIONDI G. , VIENNA A. , PEÑA GARCIA J. A. , MASCIE-TAYLOR C. G. N.
Published: February 2005

Surnames were obtained for the second half of the 20th century from civil and religious marriage registers on fifteen Provençal-Italian and five Italian villages of Cuneo Province, Italy. To insert in the analysis an outward comparison, surnames from two Italian villages of Turin Province, one parish of Turin, one village of Alessandria Province and one village of Asti Province were also collected. Ethnicity does not seem to be the main factor affecting the present genetic structure of the Provençal-Italians. They are an open community, and evidence the end of the genetic isolation of the alpine populations.
Explaining Mercosur's Survival: Strategic Sources of Argentine–Brazilian Convergence
Authors: MERA LAURA GOMEZ
Published: February 2005

This article aims to address a fundamental question for analysts and students of MERCOSUR: what explains the bloc's survival despite its recurrent crises and frequent pessimistic forecasts predicting its collapse? It argues that the maintenance of co-operation after 1999, when the economic and political economy rationale of the project had almost disappeared, is best understood in terms of the convergent strategic interests of MERCOSUR partners. This convergence of interests in the continuity of the regional regime reflects three types of strategic incentives. First, defensive considerations reflecting external forces and a shared sense of vulnerability vis-à-vis the external environment have provided the main motivation for partners to engage in negotiations and attempt to move the process of integration forward. Secondly, the offensive incentives faced by Brazil, given its relatively stronger position within the region have also worked to foster regional co-operation. But besides these power considerations, the sustainability of co-operation has been at least partially assisted by an emerging process of socialisation among executive officials taking place within regional institutions. These processes of increased interaction and enmeshment have reinforced interests in regional integration, giving way to positive incentives to maintain MERCOSUR.
Independence and the Redefinition of Indianness around Santa Marta, Colombia, 1750–1850
Authors: SAETHER STEINAR A.
Published: February 2005

This article explores the changing meaning of Indianness during the long independence era. Focusing on six towns around Santa Marta, it discusses why these were considered Indian in the late colonial period, why they supported the royalist cause during the Independence struggles and how their inhabitants ceased to be identified as Indians within a few decades of republican rule. While recent subaltern studies have emphasised Indian resistance against the liberal, republican states formed in early nineteenth-century Latin America, here it is argued that some former Indian communities opted for inclusion into the republic as non-Indian citizens.
Power, liability, and the free-will defence: reply to Mawson
Authors: MORRISTON WES
Published: February 2005

Tim Mawson argues that the ability to choose what one knows to be morally wrong is a power for some persons in some circumstances, but that it would be a mere liability for God. The lynchpin of Mawson's argument is his claim that a power is an ability that it is good to have. In this rejoinder, I challenge this claim of Mawson's, arguing that choosing a course of action is always an exercise of power, whether or not it is good for one to have that power. I then go on to develop an argument for saying that if (for the reasons presented by Mawson) it is not good for God to have the ability to make evil choices, then it isn't good for us to have it either, in which case the free-will defence is unsustainable.
Taming the Expellee Threat in Post–1945 Europe: Lessons from the Two Germanies and Finland
Authors: AHONEN PERTTI
Published: February 2005

This article analyses the process through which the dangers posed by millions of forced migrants were defused in continental Europe after the Second World War. Drawing on three countries – West Germany, East Germany and Finland – it argues that broad, transnational factors – the cold war, economic growth and accompanying social changes – were crucial in the process. But it also contends that bloc-level and national decisions, particularly those concerning the level of autonomous organisational activity and the degree and type of political and administrative inclusion allowed for the refugees, affected the integration process in significant ways and helped to produce divergent national outcomes.
Everyday Mussolinism: Friends, Family, Locality and Violence in Fascist Italy
Authors: BOSWORTH R. J. B.
Published: February 2005

The article uses a range of archival material to commence an investigation into how and with what assumptions Italians lived under a Mussolinian dictatorship which called itself totalitarian. It suggests that ‘revolutionary’ Fascism – what Emilio Gentile and others have seen as a new ‘political religion’ – met with some scepticism in the daily behaviour of many Italians. The family, the locality, the most helpful functioning of patron–client networks, the search for special advantage for oneself and ‘friends’ conditioned Fascist militancy and framed ‘ordinary life’, all the more because the practice of the dictatorship was itself so shot through with contradictions.
The summer northern annular mode and abnormal summer weather in 2003
Authors: Ogi Masayo , Yamazaki Koji , Tachibana Yoshihiro
Published: February 2005

The summer Northern Hemisphere annular mode (summer NAM), a new mode determined through empirical orthogonal function (EOF) analysis for each individual calendar month, can describe aspects of anomalous summers such as the summer of 2003, which featured warm temperatures in Europe, Canada and Russia and cold temperature in Japan. Atmospheric circulation anomalies of the summer NAM closely resemble the anomalies in the summer of 2003 and the summer NAM index was quite large during the period from mid‐July to early August when abnormal weather took place in Europe, Canada and Russia. The index includes representations of hemispheric double‐jet streams and blockings that support extended periods of abnormal weather. The double‐jet is formed and maintained by wave forcing during the period. In contrast to the Arctic and North Atlantic oscillations, the summer NAM pattern accounts for many of the anomalous weather features observed during summer of 2003.
Radiocarbon‐based ages and growth rates of bamboo corals from the Gulf of Alaska
Authors: Roark E. Brendan , Guilderson Thomas P. , Flood‐Page Sarah , Dunbar Robert B. , Ingram B. Lynn , Fallon Stewart J. , McCulloch Malcolm
Published: February 2005

Deep‐sea coral communities have long been recognized by fisherman as areas that support large populations of commercial fish. As a consequence, many deep‐sea coral communities are threatened by bottom trawling. Successful management and conservation of this widespread deep‐sea habitat requires knowledge of the age and growth rates of deep‐sea corals. These organisms also contain important archives of intermediate and deep‐water variability, and are thus of interest in the context of decadal to century‐scale climate dynamics. Here, we present Δ14C data that suggest that bamboo corals from the Gulf of Alaska are long‐lived (75–126 years) and that they acquire skeletal carbon from two distinct sources. Independent verification of our growth rate estimates and coral ages is obtained by counting seasonal Sr/Ca cycles and probable lunar cycle growth bands.
Effect of strong thermalization on shock dynamical behavior
Authors: Shimada Nobue , Hoshino Masahiro
Published: February 2005

The dynamics of the perpendicular shock front is examined under various plasma parameters by using particle‐in‐cell numerical simulation. As widely accepted, above the critical Mach number (∼3) the front of (quasi‐)perpendicular shocks show nonstationary behavior due to the shock self‐reformation. In much higher Mach number regime (MA > 20), we find that dynamics of the shock front self‐reformation can be modified. Nonlinear evolution of microinstabilities in the shock transition region results turbulent profiles in a microscopic view (≤c/ωpe), while, from a macroscopic view (>several c/ωpe) because of rapid, strong thermalization in the shock transition region, the localized accumulation of the plasma due to ion dynamics is smeared out in both of the velocity phase space and real space. As a result, the shock self‐reformation is realized within a reduced time and space. We can say there is a possibility that rapid, strong dissipation helps to stabilize the macroscopic shock front dynamics; the shock self‐reformation still persists, though. The strong thermalization is caused by the nonlinear evolution of two‐stream instability between the electron and the reflected/incident ion components and following ion‐acoustic instability. We think that the modification of the shock self‐reformation process observed in high Mach number regime indicates an important role of electron kinetics and heating in the macroscopic shock front behavior.
The SNARE Ykt6 is released from yeast vacuoles during an early stage of fusion
Authors: Dietrich Lars E P , Peplowska Karolina , LaGrassa Tracy J , Hou Haitong , Rohde Jan , Ungermann Christian
Published: February 2005

The farnesylated SNARE (N‐ethylmaleimide‐sensitive factor attachment protein receptor) Ykt6 mediates protein palmitoylation at the yeast vacuole by means of its amino‐terminal longin domain. Ykt6 is localized equally to membranes and the cytosol, although it is unclear how this distribution is mediated. We now show that Ykt6 is released efficiently from vacuoles during an early stage of yeast vacuole fusion. This release is dependent on the disassembly of vacuolar SNAREs (priming). In recent literature, it had been demonstrated for mammalian Ykt6 that the membrane‐bound form is both palmitoylated and farnesylated at its carboxy‐terminal CAAX box, whereas soluble Ykt6 is only farnesylated. In agreement with this, we find that yeast Ykt6 becomes palmitoylated in vitro at its C‐terminal CAAX motif. Mutagenesis of the potential palmitoylation site in yeast Ykt6 prevents stable membrane association and is lethal. On the basis of these and other findings, we speculate that Ykt6 is released from membranes by depalmitoylation. Such a mechanism could enable recycling of this lipid‐anchored SNARE from the vacuole independent of retrograde transport.
Epidermal stem cells: the cradle of epidermal determination, differentiation and wound healing
Authors: Morasso Maria I. , Tomic‐Canic Marjana
Published: February 2005

The field of epidermal stem cells has dramatically advanced in the last decade, leading to a better understanding of the molecular factors, signalling pathways and cellular events that identify and characterize stem cells, thus revealing their immense potential for therapeutic use. Furthermore, multipotent epidermal stem cells present the major advantage of easy accessibility with the discovery of their specific location within the bulge of the hair follicle. This review focuses on the most recent findings on epidermal stem cells, and their potential role in initial epidermal commitment, differentiation and wound healing processes in the skin.
What does it take to make a heart?
Authors: Pandur Petra
Published: February 2005

Ever increasing advances are being made in our quest to understand what it takes to direct pluripotent precursor cells to adopt a specific developmental fate. Eventually, the obvious goal is that targeted manipulation of these precursor cells will result in an efficient and reliable production of tissue‐specific cells, which can be safely employed for therapeutic purposes. We have gained an incredible insight as to which molecular pathways are involved in governing neural, skeletal and cardiac muscle fate decisions. However, we still face the challenge of how to direct, for example, a cardiac fate in stem cells in the amounts needed to be employed for regenerative means. Equally importantly, we need to resolve critical questions such as: can the in vitro generated cardiomyocytes actually functionally replace damaged heart tissue? Here I will provide an overview of the molecules and signalling pathways that have first been demonstrated in embryological studies to function in cardiogenesis, and summarize how this knowledge is being applied to differentiate mouse and human embryonic stem cells into cardiomyocytes.