bluuebunny/crossref_metadata_2025 huggingface dataset:
Abnormal plasticity of the sensorimotor cortex to slow repetitive transcranial magnetic stimulation in patients with writer's cramp
Authors: Bäumer Tobias , Demiralay Cüneyt , Hidding Ute , Bikmullina Rosalia , Helmich Rick C. , Wunderlich Silke , Rothwell John , Liepert Joachim , Siebner Hartwig R. , Münchau Alexander
Published: November 2006

Previous studies demonstrated functional abnormalities in the somatosensory system, including a distorted functional organization of the somatosensory cortex (S1) in patients with writer's cramp. We tested the hypothesis that these functional alterations render S1 of these patients more susceptible to the “inhibitory” effects of subthreshold 1 Hz repetitive transcranial magnetic stimulation (rTMS) given to S1. Seven patients with writer's cramp and eight healthy subjects were studied. Patients also received rTMS to the motor cortex hand area (M1). As an outcome measure, short‐latency afferent inhibition (SAI) was tested. SAI was studied in the relaxed first dorsal interosseous muscle using conditioning electrical stimulation of the index finger and TMS pulses over the contralateral M1. Baseline SAI did not differ between groups. S1 but not M1 rTMS reduced SAI in patients. rTMS had no effects on SAI in healthy subjects. Because SAI is mediated predominantly at a cortical level in the sensorimotor cortex, we conclude that there is an abnormal responsiveness of this area to 1 Hz rTMS in writer's cramp, which may represent a trait toward maladaptive plasticity in the sensorimotor system in these patients. © 2006 Movement Disorder Society
Single‐shot quantitative perfusion imaging of the human lung
Authors: Pracht Eberhard D. , Fischer André , Arnold Johannes F.T. , Kotas Markus , Flentje Michael , Jakob Peter M.
Published: November 2006

The major drawback to quantitative perfusion imaging using arterial spin labeling (ASL) techniques is the need to acquire two images (tag and control), which must be subtracted in order to obtain a perfusion‐weighted image. This can potentially result in misregistration artifacts, especially in lung imaging, due to varying lung inflation levels in different breath‐holds. In this work a double inversion recovery (DIR) imaging technique that yields perfusion‐weighted images of the human lung in a single shot is presented. This technique ensures the complete suppression of background tissue while it preserves signal from the blood. Furthermore, the perfusion‐weighted images and an additional (independent) acquired reference scan can be used to obtain quantitative perfusion information from the lungs. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Theory of differential equations in discontinuous piecewise‐defined functions
Authors: Herrera I.
Published: November 2006

A truly general and systematic theory of finite element methods (FEM) should be formulated using, as trial and test functions, piecewise‐defined functions that can be fully discontinuous across the internal boundary, which separates the elements from each other. Some of the most relevant work addressing such formulations is contained in the literature on discontinuous Galerkin (dG) methods and on Trefftz methods. However, the formulations of partial differential equations in discontinuous functions used in both of those fields are indirect approaches, which are based on the use of Lagrange multipliers and mixed methods, in the case of dG methods, and the frame, in the case of Trefftz method. This article addresses this problem from a different point of view and proposes a theory, formulated in discontinuous piecewise‐defined functions, which is direct and systematic, and furthermore it avoids the use of Lagrange multipliers or a frame, while mixed methods are incorporated as particular cases of more general results implied by the theory. When boundary value problems are formulated in discontinuous functions, well‐posed problems are boundary value problems with prescribed jumps (BVPJ), in which the boundary conditions are complemented by suitable jump conditions to be satisfied across the internal boundary of the domain‐partition. One result that is presented in this article shows that for elliptic equations of order 2m, with m ≥ 1, the problem of establishing conditions for existence of solution for the BVPJ reduces to that of the “standard boundary value problem,” without jumps, which has been extensively studied. Actually, this result is an illustration of a more general one that shows that the same happens for any differential equation, or system of such equations that is linear, independently of its type and with possibly discontinuous coefficients. This generality is achieved by means of an algebraic framework previously developed by the author and his collaborators. A fundamental ingredient of this algebraic formulation is a kind of Green's formulas that simplify many problems (some times referred to as Green‐Herrera formulas). An important practical implication of our approach is worth mentioning: “avoiding the introduction of the Lagrange multipliers, or the ‘frame’ in the case of Trefftz‐methods, significantly reduces the number of degrees of freedom to be dealt with.” © 2006 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2007
Instantaneous rate constants in physical organic chemistry: application to acyl transfer reactions of p‐nitrophenyl acetate to hydroxide ion
Authors: Parker Vernon D.
Published: November 2006

The instantaneous rate constant (IRC)–time profiles for single‐step mechanisms are straight lines with zero slope. The IRC–time profiles for reactions taking place in more than a single step depend upon whether decay of reactant or evolution of product concentration is monitored. When reactant decay is monitored, the IRC–time plot extrapolated to zero time is equal to the rate constant for the initial step (kf) in the reaction while the IRC–time profile for product evolution extrapolates to zero at t = 0. The IRC–time profiles for monitoring reactant decay and product evolution converge to a plateau value which can be equated to the rate constant under steady‐state conditions (ks.s). Two independent procedures for calculating IRC–time profiles were developed and tested for both simple and complex mechanisms. The first method is initiated with a least squares correlation over the first 11 points of a 2000‐point ln(1−ER)−time profile (ER designates extent of reaction). The IRC at the midpoint (IRC(6)) of the time interval is assigned the value of −S (where S is the slope of the correlation). The second correlation is over points 2–12 and provides a value of IRC(7). This procedure is continued until IRC(6) to IRC(1995) have been generated. The second method involves a 5th order polynomial smooth of the (1−ER)/time profile before calculating IRC at the midpoints between successive points. The limitations of the two IRC procedures are discussed. The IRC procedures are applied to experimental absorbance–time profiles for the acyl transfer reactions of p‐nitrophenyl acetate to hydroxide ion in water and in aqueous acetonitrile. In water, no significant deviations from pseudo first‐order kinetics were observed. A dramatic change in IRC/time profiles was observed on changing solvents to aqueous acetonitrile. Under the latter conditions the IRC analyses were observed to be consistent with a 2‐step mechanism. Copyright © 2006 John Wiley & Sons, Ltd.
In Vitro effect of D‐004, a lipid extract of the ground fruits of the cuban royal palm (Roystonea regia), on rat microsomal lipid peroxidation
Authors: Menéndez Roberto , Más Rosa , Pérez Yohani , González R. M.
Published: November 2006

D‐004 is a lipid extract of the fruits of the Cuban royal palm (Roystonea regia) containing a mixture of saturated fatty acids. D‐004 inhibits prostate hyperplasia (PH) induced with testosterone, in rodents. Since fatty acids inhibit lipid peroxidation (LP), this study investigated whether D‐004 prevents in vitro LP. D‐004 (0.9–1000 µg/mL) markedly and dose‐dependently inhibited in vitro iron‐induced LP in native brain and liver microsomes. D‐004 showed hydroxyl radical scavenging activity, which could explain partially its antioxidant effect on microsomal iron‐induced LP, but it was unable to scavenge superoxide and ABTS radicals, indicating a limited radical scavenging activity. Also, D‐004 inhibited CCl4‐mediated LP in active liver microsomes through a decreased generation of radical species rather than a radical trapping action on CCl4‐derived radical species. D‐004 also inhibited lipooxygenase (LOX) and cyclooxygenase (COX) activities, and the generation of protein‐associated carbonyl groups after LP. Since increased oxidative stress has been linked to PH, the antioxidant effect of D‐004 shown here could contribute to explaining its beneficial effects on T‐induced PH in rodents. Nevertheless, this study shows only in vitro results. Further studies should investigate whether D‐004 also exhibits antioxidant effects in vivo. Copyright © 2006 John Wiley & Sons, Ltd.
Determination of the surface energetics of surface modified calcium carbonate using inverse gas chromatography
Authors: Calhoun Allison , Chiang Ethan
Published: November 2006

Stearic acid and several silane surface coating agents, including propyltriethoxysilane, aminopropyltriethoxysilane, and diphenyldimethoxysilane, were applied to uncoated calcium carbonate samples at coating levels ranging from 0 to 2.0% by weight. The surface energy of these coated calcium carbonate samples, as determined by inverse gas chromatography, decreased relative to that of the native mineral with increasing coating level for both the stearic acid and the diphenyldimethoxysilane. This decrease in energy arises from the nonpolar functionality of the coating masking the high energy surface of the mineral. The propyltriethoxysilane generated a decreasing surface energy with increase in coating level up to a theoretical monolayer coating. Above this coating level, an inverted bilayer formed that increased the surface energy of the mineral. Aminopropyltriethoxysilane caused an initial decrease in surface energy relative to that of the native mineral but then retained an approximately constant surface energy at all coating levels. This observation arises from the energetic groups presented at the surface of the mineral regardless of the orientation of the silane. J. VINYL ADDIT. TECHNOL., 12:174–182, 2006. © 2006 Society of Plastics Engineers
Pentaphenyl‐1,3,2‐dioxaphospholane as a reactive flame retardant
Authors: Howell Bob A. , Uzibor Joel
Published: November 2006

2,4,4,5,5‐Pentaphenyl‐1,3,2‐dioxaphospholane may be generated by treating benzpinacol with (dichloro)phenylphosphine. The phospholane contains a strained carbon–carbon bond which undergoes thermally‐induced homolysis at 70°C to generate a diradical capable of initiating styrene polymerization. The polymer generated from decomposition of the phospholane in the presence of styrene monomer contains phosphorus in the mainchain. This polymer exhibits thermal stability comparable to that of conventional polystyrene but decreased flammability. J. VINYL ADDIT. TECHNOL., 12:192–197, 2006. © 2006 Society of Plastics Engineers
N, NH, and NH2 radical densities in a remote Ar–NH3–SiH4 plasma and their role in silicon nitride deposition
Authors: van den Oever P. J. , van Helden J. H. , van Hemmen J. L. , Engeln R. , Schram D. C. , van de Sanden M. C. M. , Kessels W. M. M.
Published: November 2006

The densities of N, NH, and NH2 radicals in a remote Ar–NH3–SiH4 plasma used for high-rate silicon nitride deposition were investigated for different gas mixtures and plasma settings using cavity ringdown absorption spectroscopy and threshold ionization mass spectrometry. For typical deposition conditions, the N, NH, and NH2 radical densities are on the order of 1012cm−3 and the trends with NH3 flow, SiH4 flow, and plasma source current are reported. We present a feasible reaction pathway for the production and loss of the NHx radicals that is consistent with the experimental results. Furthermore, mass spectrometry revealed that the consumption of NH3 was typically 40%, while it was over 80% for SiH4. On the basis of the measured N densities we deduced the recombination and sticking coefficient for N radicals on a silicon nitride film. Using this sticking coefficient and reported surface reaction probabilities of NH and NH2 radicals, we conclude that N and NH2 radicals are mainly responsible for the N incorporation in the silicon nitride film, while Si atoms are most likely brought to the surface in the form of SiHx radicals.
Collision-induced annealing of octanethiol self-assembled monolayers by high-kinetic-energy xenon atoms
Authors: Fogarty Daniel P. , Kandel S. Alex
Published: November 2006

Collisions with high-energy xenon atoms (1.3eV) induce structural changes in octanethiol self-assembled monolayers on Au(111). These changes are characterized at the molecular scale using an in situ scanning tunneling microscope. Gas-surface collisions induce three types of structural transformations: domain boundary annealing, vacancy island diffusion, and phase changes. Collision-induced changes that occur tend to increase order and create more stable structures on the surface. We propose a mechanism where monolayer transformations are driven by large amounts of vibrational energy localized in the alkanethiol molecules. Because we monitor incremental changes over small regions of the surface, we can obtain structural information about octanethiol monolayers that cannot be observed directly in scanning tunneling microscopy images.
COAST: Controllable approximative stochastic reaction algorithm
Authors: Wagner Holger , Möller Mark , Prank Klaus
Published: November 2006

We present an approximative algorithm for stochastic simulations of chemical reaction systems, called COAST, based on three different modeling levels: for small numbers of particles an exact stochastic model; for intermediate numbers an approximative, but computationally more efficient stochastic model based on discrete Gaussian distributions; and for large numbers the deterministic reaction kinetics. In every simulation time step, the subdivision of the reaction channels into the three different modeling levels is done automatically, where all approximations applied can be controlled by a single error parameter for which an appropriate value can easily be found. Test simulations show that the results of COAST simulations agree well with the outcomes of exact algorithms; however, the asymptotic run times of COAST are asymptotically proportional to smaller powers of the particle numbers than exact algorithms.
Calculations of scattering of N2 molecules from Ru(0001)
Authors: Ambaye Hailemariam , Manson J. R.
Published: November 2006

Recent experimental measurements of state resolved scattering of nitrogen molecules from a Ru(0001) surface are discussed in comparison with a mixed quantum-classical theory that has given reasonable explanations for similar data on other systems. Acceptable agreement between data and calculations is obtained, but only upon assuming an effective mass of the surface equal to 2.3 times the mass of a single Ru atom.
Hydrostatic-pressure-induced porous gallium nitride from nanotube bundles: An ab initio study
Authors: Hao Shaogang , Zhou Gang , Duan Wenhui , Wu Jian , Gu Bing-Lin
Published: November 2006

Ab initio calculations show that (5,5) and (6,6) single-walled gallium nitride nanotubes (GaN NTs) in bundles could aggregate spontaneously to form new condensed phases when bundled tubes are close enough under hydrostatic pressure. The new GaN phases have typical porous structures, constructed by alternating tetragons and hexagons around the original tube walls. Owing to the different compatibilities of the chirality of the tube with the symmetry of the array, the new phase formed from (5,5) GaN NT bundles is triclinic and that from (6,6) ones is hexagonal. These porous GaN phases possess tetrahedral bonding corresponding to sp3 hybridization, different from sp2 hybridized bonding in individual GaN NTs. The interaction between tubes not only controls the structural transformation but also influences the electronic structure of porous GaN. We expect that the two-dimensional-channeled porous structure of GaN is advantageous for the usage of GaN as the molecular sieve and as the excellent dilute magnetic semiconductor by considerable magnetic doping.
247
nm
solar-blind ultraviolet p-i-n photodetector
Authors: Kuryatkov V. V. , Borisov B. A. , Nikishin S. A. , Kudryavtsev Yu. , Asomoza R. , Kuchinskii V. I. , Sokolovskii G. S. , Song D. Y. , Holtz M.
Published: November 2006

We describe solar-blind p-i-n photodetectors based on short period superlattices of AlN∕Al0.08Ga0.92N. The devices are grown using gas source molecular beam epitaxy with ammonia on transparent sapphire substrates. The cutoff wavelength for the device is 247nm. For diodes with 150μm diameter mesas and sidewall surfaces passivated in oxygen plasma, we obtain extremely low dark leakage current of ∼3pA∕cm2 and high zero-bias resistance of ∼6×1014Ω. At 10V reverse bias the observed responsivity is 62mA∕W.
Incommensurate modulation structure in ferroelectric Ca0.28Ba0.72Nb2O6 single crystals of tungsten bronze structure
Authors: Lu C. J. , Qi Y. J. , Li J. Q. , Zhang H. J. , Wang J. Y.
Published: November 2006

Incommensurate modulation structure in uniaxial relaxor ferroelectric Ca0.28Ba0.72Nb2O6 single crystals was investigated using transmission electron microscopy (TEM). The wave-modulation vector can be expressed as q=(1∕2)c*+(1+δ)(a*−b*)∕4, where the incommensurability parameter δ was determined to be about 0.09 from [110] diffraction pattern. High-resolution TEM observations along [110] zone provided direct evidence of the incommensurate superstructure. Structural modulation was also evident by high-resolution TEM images through [001] zone, where a sinusoidal variation along [110] and [11¯0] was identified. The incommensurate superlattice structure is caused by the uniform mixing of slabs of two orthorhombic cells.
Parallel microparticle manipulation using an imaging fiber-bundle-based optical tweezer array and a digital micromirror device
Authors: Tam Jenny M. , Biran Israel , Walt David R.
Published: November 2006

In this letter, the authors present a method to selectively capture and release microparticles using an imaging fiber-bundle-based optical tweezer array system. By integrating a digital micromirror device into a tweezer array system, patterns of optical traps can be generated on the distal face of a fiber bundle. A 2×2 array of traps was created to capture, release, and recapture microparticles in solution. This straightforward process enables individual control of the size, shape, and position of each trap in the array.
Search for fully spin-polarized semiconductor heterostructures: The candidate (Zn,Co)O
Authors: Marin I. S. P. , Sipahi G. M. , Boselli M. A. , da Cunha Lima I. C.
Published: November 2006

The authors suggest geometrical arrangements in (Zn,Co)O multilayered structures which maximize the spin polarization densities. The theoretical argument is supported by electronic structure calculations based on a two-band effective mass model adapted to describe these systems and solved self-consistently with the aid of Poisson’s equation. The exchange correlation, the strain terms, and the magnetic interactions are all included in the Hamiltonian. From their results a set of parameters can be determined to maximize the presence of spin-polarized charge distributions inside or outside the nonmagnetic layers, which enhances the transition temperature to ferromagnetism or the carrier mobility in the system.
Electro-optical characteristics of plasma display panel with Mg1−xSixO protecting thin films deposited by an electron-beam evaporation method
Authors: Lee Don-Kyu , Park Chung-Hoo , Lee Hae June , Choi Woo-Sung , Kim Dong-Hyun , Lee Ho-Jun
Published: November 2006

The effect of Si doping in MgO has been investigated in order to improve the material properties of the MgO protecting layer in plasma display panels. A small amount of Si was added to the MgO pellet while the MgO layer was being deposited by using an electron-beam evaporation method. Both the surface characteristics of the protecting layer and the electro-optical properties of 4in. test panels were investigated, such as firing and sustain voltages, luminous efficacy, addressing jitter, and image sticking. The firing voltage is minimized when the Si concentration is 0.03%∼0.04%, where the luminous efficacy increases up to 35% compared with that of the conventional MgO film, and the boundary image sticking also shows good characteristics around the Si concentration level by 0.04%.
Multifunctional design of high-transition-temperature directly coupled superconducting-quantum-interference-device magnetometers on a chip
Authors: Chen Kuen-Lin , Wu C. H. , Chen J. C. , Yang H. C. , Chen J. H. , Horng H. E.
Published: November 2006

We have designed four multifunctional high-transition-temperature directly coupled superconducting-quantum-interference-device (SQUID) magnetometers on a 10×10mm2 SrTiO3 bicrystal substrate. Each magnetometer is composed of two serial bare SQUIDs. These magnetometers can be connected to four kinds of first-order electronic planar gradiometers or two kinds of second-order electronic planar gradiometers by using analog subtracting electronic circuits. The noise spectra of each magnetometer, two first-order electronic planar gradiometers, and a second-order planar gradiometer were measured. We measured the small magnetic signal generated from a double D coil to show that this design could supplement the deficiency of a magnetometer.
Preparation and characterization of ferromagnetic DO3-phase Fe3Si thin films on silicon-on-insulator substrates for Si-based spin-electronic device applications
Authors: Nakane Ryosho , Tanaka Masaaki , Sugahara Satoshi
Published: November 2006

The authors developed a preparation technique of stoichiometric and off-stoichiometric ferromagnetic Fe3+δSi1−δ thin films with a DO3 phase structure using silicon-on-insulator (SOI) substrates. Ferromagnetic Fe3+δSi1−δ films were formed by thermally activated silicidation reaction between an ultrathin SOI layer and a Fe layer deposited on it, induced by rapid thermal annealing. Their chemical composition was precisely controlled by the relative thickness ratio of the SOI and Fe layers, and highly oriented DO3-phase polycrystalline Fe3+δSi1−δ films were obtained with annealing temperature ranging from 620 to 780°C. The Fe3+δSi1−δ films exhibited ferromagnetic nature with the Curie temperature much higher than room temperature.
Influence of Ge atoms on mobility and junction properties of thin-film transistors fabricated on solid-phase crystallized poly-SiGe
Authors: Mitsui Minoru , Arimoto Keisuke , Yamanaka Junji , Nakagawa Kiyokazu , Sawano Kentarou , Shiraki Yasuhiro
Published: November 2006

The transport properties of thin-film transistors (TFTs) fabricated on polycrystalline-SiGe films, which were formed by solid-phase crystallization of amorphous-Si1−xGex (x=0, 0.3, 0.5, and 0.7) films, were studied. The mobility of TFTs increases as the Ge concentration increases from 0% to 30% and the mobility decreases as the Ge concentration exceeds 30%, which agrees with the Ge concentration dependence of the grain size. The generation rates and the effective lifetimes of electron-hole pairs at the p-n junctions of TFTs increase and decrease monotonically with increasing Ge concentration, respectively, which means that the grain boundary defects in p-n junctions increase with increasing Ge concentration.
Photoluminescence spectra of Eu-doped GaN with various Eu concentrations
Authors: Sawahata Junji , Seo Jongwon , Chen Shaoqiang , Takiguchi Mikio , Saito Daisuke , Nemoto Shinya , Akimoto Katsuhiro
Published: November 2006

Variation of the luminescence spectra of Eu-doped GaN with varying Eu concentration ranging from 0.6to8.0at.% was investigated. Eu-related luminescence originating from the D05-F27 transition of Eu3+ was observed at about 622nm. The luminescence basically consisted of three peaks. The relative intensity of the three peaks changed remarkably at the Eu concentration of around 2.0–3.5at.% which corresponds to a structural phase transition from a single crystalline to a polycrystalline structure. This indicates that the incorporation site of Eu in GaN is very sensitive to the structural properties of the GaN host material.
Linking Discourse and Space: Towards a Cultural Sociology of Space in Analysing Spatial Policy Discourses
Authors: Richardson Tim , Jensen Ole B.
Published: November 2006

The aim of this paper is to explore how spatialities are 'constructed' in spatial policy discourses and to explore how these construction processes might be conceptualised and analysed. To do this, we discuss a theoretical and analytical framework for the discourse analysis of socio-spatial relations. Our approach follows the path emerging within planning research focusing on the relations between rationality and power, making use of discourse analytics and cultural theoretical approaches to articulate a cultural sociology of space. We draw on a variety of theoretical sources from critical geography to sociology to argue for a practice- and culture-oriented understanding of the spatiality of social life. The approach hinges on the dialectical relation between material practices and the symbolic meanings that social agents attach to their spatial environment. Socio-spatial relations are conceptualised in terms of their practical 'workings' and their symbolic 'meaning', played out at spatial scales from the body to the global-thus giving notion to an analysis of the 'politics of scale'. The discourse analytical approach moves away from textually oriented approaches to explore the relations between language, space and power. In the paper, we use examples of the articulation of space in the emerging field of European spatial policy. It is shown how the new spatial policy discourse creates the conditions for a new set of spatial practices which shape European space, at the same time as it creates a new system of meaning about that space, based on the language and ideas of polycentricity and hypermobility.
Expression of active Akt protects against tamoxifen‐induced apoptosis in MCF‐7 Cells
Authors: Shin Incheol , Arteaga Carlos L.
Published: November 2006

We investigated the effect of constitutive active Akt expression on anti‐proliferative and apoptotic effect of tamoxifen in MCF‐7 human breast cancer cells. Forced expression of AktDD (T308D, S473D) resulted in increased phosphorylation of GSK3β, a physiological substrate of Akt. When estrogen receptor (ER) mediated transcription was determined by luciferase assays, there was more than 2‐fold increase in estradiol‐dependent transcription in MCF‐7 cells overexpressing AktDD (MCF‐7 AktDD) compared to vector control cells (MCF‐7 vec). MCF‐7 AktDD cells showed increased proliferation in a medium containing charcoal stripped serum supplemented with estradiol. When the cell cycle profiles were examined, there was an increase in S‐phase and a reduction in G1 phase in MCF‐7 AktDD cells as compared to MCF‐7 vec cells. Overexpression of AktDD also attenuated tamoxifen‐mediated apoptosis. These results suggest that Akt could confer resistance to anti‐estrogen mediated cell death and inhibition of proliferation.
iubmb Life, 58: 664 ‐ 669, 2006
PGE1 stimulation of HEK293 cells generates multiple contiguous domains with different [cAMP]: role of compartmentalized phosphodiesterases
Authors: Terrin Anna , Di Benedetto Giulietta , Pertegato Vanessa , Cheung York-Fong , Baillie George , Lynch Martin J. , Elvassore Nicola , Prinz Anke , Herberg Friedrich W. , Houslay Miles D. , Zaccolo Manuela
Published: November 2006

There is a growing appreciation that the cyclic adenosine monophosphate (cAMP)–protein kinase A (PKA) signaling pathway is organized to form transduction units that function to deliver specific messages. Such organization results in the local activation of PKA subsets through the generation of confined intracellular gradients of cAMP, but the mechanisms responsible for limiting the diffusion of cAMP largely remain to be clarified. In this study, by performing real-time imaging of cAMP, we show that prostaglandin 1 stimulation generates multiple contiguous, intracellular domains with different cAMP concentration in human embryonic kidney 293 cells. By using pharmacological and genetic manipulation of phosphodiesterases (PDEs), we demonstrate that compartmentalized PDE4B and PDE4D are responsible for selectively modulating the concentration of cAMP in individual subcellular compartments. We propose a model whereby compartmentalized PDEs, rather than representing an enzymatic barrier to cAMP diffusion, act as a sink to drain the second messenger from discrete locations, resulting in multiple and simultaneous domains with different cAMP concentrations irrespective of their distance from the site of cAMP synthesis.
The need for previously untreated patient population studies in understanding the development of factor VIII inhibitors
Authors: GOMPERTS E. D.
Published: November 2006

Summary.  The presence of inhibitory antibodies to factor VIII (FVIII) remains one of the most serious complications of haemophilia therapy. Accordingly, understanding risk factors that may contribute to inhibitor developments in young patients with haemophilia A continues to be an area of great interest. Previously untreated patient (PUP) population studies have been instrumental in understanding the aetiology of inhibitor development. These studies have revealed the importance of risk factors such as clotting factor exposure history, ethnicity, and FVIII genotype in the development of inhibitors, while also providing insights into potential risk factors that may be related to therapeutic practice. However, due to differences in study designs and patient populations among previous PUP studies, there are limitations to the value of these studies in deciphering the role of potential risk factors. Therefore, future PUP studies should be prospective, consistent in their study designs and consider all established parameters and also those that possibly may influence inhibitor formation, thereby facilitating a better understanding of the aetiology of inhibitor formation in haemophilia A patients.
The feasibility of total ankle prosthesis for severe arthropathy in haemophilia and prothrombin deficiency
Authors: VAN DER HEIDE H. J. L. , NOVÁKOVÁ I. , DE WAAL MALEFIJT M. C.
Published: November 2006

Summary.  The standard treatment for end‐stage arthropathy of the ankle joint in haemophilia has been fusion of the ankle joint. Total ankle replacement is used in osteoarthritis and especially in rheumatoid arthritis with good medium‐term results. In this case series three patients are being described, in which a total of five total ankle replacements have been preformed. After a median follow up of 4.3 years (range 1–8.7) all prostheses were still in place and did not show any signs of loosening. Clinical scores showed a good to excellent result. In this small series total ankle replacement in patients with bleeding disorders show promising results. Further studies are needed to show the value of this relatively new type of surgery in haemophilic patients.
The 80th anniversary of von Willebrand's disease: history, management and research
Authors: FEDERICI A. B. , BERNTORP E. , LEE C. A.
Published: November 2006

Summary.  The history of von Willebrand's disease (VWD) is fascinating because it demonstrates how good clinical observations, genetic studies and biochemical skills can improve basic understanding of a disease and its management. The continuous efforts of scientists and clinicians during the last 80 years have significantly improved the knowledge of von Willebrand factor (VWF) structure and function and the management of VWD. Diagnosis of phenotype and genotype is now available in many countries and treatment is becoming more specific according to the VWD type. Any therapeutic agents must correct the dual defect of haemostasis, i.e. the abnormal platelet adhesion due to reduced and/or dysfunctional and low levels of factor VIII (FVIII) associated with VWF defects. Desmopressin (DDAVP) is the treatment of choice for type 1 VWD because it induces release of VWF from cellular compartments. Plasma virally inactivated VWF concentrates containing FVIII are effective and safe in patients unresponsive to DDAVP. There are advanced plans to develop a recombinant VWF but this product will require the concomitant administration of FVIII for the control of acute bleeds. Basic research studies on cellular biology, biochemistry and immunology have confirmed the role of VWF as a crucial participant in both haemostasis and thrombosis as its main biological activity is to support platelet adhesion–aggregation in the circulation. Retrospective and prospective clinical research studies, including bleeding history and laboratory markers for diagnosis as well as the use of DDAVP and VWF concentrates to manage or prevent bleeds in patients with VWD have been essential to provide general guidelines for VWD management. The large number of publications quoting VWD and VWF emphasizes the important role of VWF in medicine.
Sexual health education for people with mental health problems: what can we learn from the literature?
Authors: HIGGINS A. , BARKER P. , BEGLEY C. M.
Published: November 2006

Research into sexual risk behaviour among people with ‘severe’ mental health problems suggested that they are likely to engage in high‐risk sexual behaviour, for a number of reasons, putting them at risk of sexually transmitted diseases. The aim of this review is to describe approaches, content and outcomes of sexual health education programmes, developed and implemented for people with mental health problems. A literature review from 1980 to 2005 was carried out using the electronic databases CINAHL, PsycINFO, British Nursing Index, Pubmed and Medline, and the Cochrane library was also searched. The literature search was confined to papers written in English. The keywords ‘sexuality’, ‘sexual health education’, ‘sexual health promotion’, ‘HIV’, ‘sexually transmitted disease’ were combined with ‘mental illness’, ‘chronic mental illness’‘severe mental illness’‘persistent mental illness’‘psychiatry’, ‘mental disorder’, ‘education interventions’ and ‘evaluation’. A vast amount of literature was recovered on sexual risk behaviour in people with severe mental health problems, and sexual dysfunction as a result of prescribed medication. As the focus of the review was on sexual health education, this literature was omitted. Although the literature on sexual health education for people experiencing mental health problems was sparse, 14 studies were located that either described or evaluated sexual health education programmes. Most sex education programmes focused on topics such as HIV and other sexually transmitted diseases, negotiating safe sex and skill development in condom use. Findings suggested that the people who attended benefited from sexual health education programmes, facilitated in a sensitive and supportive manner. Education tended to produce a reduction in sexual risk behaviour as opposed to complete cessation. Nevertheless, it is appropriate to consider integrating such education with service provision. The results of the review provide guidance to service providers and mental health nurses wishing to develop and evaluate sexual health education programmes for service users. Areas for future research are also identified.
Living by themselves? Psychiatric nurses’ views on supported housing for persons with severe and persistent mental illness
Authors: HÖGBERG T. , MAGNUSSON A. , LÜTZÉN K.
Published: November 2006

The main principle directing the development of supported dwellings for persons with long‐term mental illness is that to live in the community would improve their quality of life. The aim of this study was to describe psychiatric nurses’ experiences of different types of supported dwelling for persons with long‐term mental illness, and their views on what they consider to be important principles to provide for in order to facilitate their social integration into the community. Nine psychiatric nurses were interviewed. A qualitative content analysis revealed ‘attempting to uphold the principle, respect for the patient’s right to self‐determination’ as the main theme, which was linked to three sub‐themes: the nurses’ view on their moral responsibility; the nurses’ views on social norms that patients must follow in order to be accepted by their neighbours; and the nurses’ views on supported dwelling of good quality. The nurses perceived that personal contact between the neighbour and the mentally ill person was one essential way to reduce fear of the mentally ill person. They viewed themselves as a link between the mentally ill person and other neighbours. Without the personal contact between the mentally ill person and the neighbours, there may be a risk that the integration will fail no matter how excellent the supported dwelling is framed.
Temporal Parts and Timeless Parthood
Authors: Olson Eric T.
Published: November 2006

What is a temporal part? Most accounts explain it in terms of timeless parthood: a thing's having a part without temporal qualification. Some find this hard to understand, and thus find the view that persisting things have temporal parts—four‐dimensionalism—unintelligible. T. Sider offers to help by defining temporal parthood in terms of a thing's having a part at a time. I argue that no such account can capture the notion of a temporal part that figures in orthodox four‐dimensionalism: temporal parts must be timeless parts. This enables us to state four‐dimensionalism more clearly.
Exchange Rate Regimes and Reforms: A Panel Analysis for the World versus OECD Countries*
Authors: Belke Ansgar , Herz Bernhard , Vogel Lukas
Published: November 2006

This paper examines the contemporaneous relationship between the exchange rate regime and structural economic reforms over a period of 30 years. Using panel data techniques, we look at both a broad ‘world sample’ and an OECD country sample. We investigate empirically whether structural reforms have complemented or substituted for monetary commitment in the attempt to improve macroeconomic performance. Our results suggest that, on average, an exchange rate rule positively correlates with the amount of overall structural reforms and of trade liberalization in particular. However, we do not find a significant and robust impact of exchange rate commitment on labour and product market reform. The results are similar for both the wider, more heterogeneous world sample and the panel of OECD economies. They contradict the hypothesis that exchange rate commitments may have slowed the pace of structural reform, but neither provides robust evidence that losing the possibility of an exchange rate adjustment promotes labour and product market reforms.
Evaluation of Aromatherapy in Treating Postoperative Pain: Pilot Study
Authors: Kim Jung T. , Wajda Michael , Cuff Germaine , Serota David , Schlame Michael , Axelrod Deborah M. , Guth Amber A. , Bekker Alex Y.
Published: November 2006

Abstract:  This study compared the analgesic efficacy of postoperative lavender oil aromatherapy in 50 patients undergoing breast biopsy surgery. Twenty‐five patients received supplemental oxygen through a face mask with two drops of 2% lavender oil postoperatively. The remainder of the patients received supplemental oxygen through a face mask with no lavender oil. Outcome variables included pain scores (a numeric rating scale from 0 to 10) at 5, 30, and 60 minutes postoperatively, narcotic requirements in the postanesthesia care unit (PACU), patient satisfaction with pain control, as well as time to discharge from the PACU. There were no significant differences in narcotic requirements and recovery room discharge times between the two groups. Postoperative lavender oil aromatherapy did not significantly affect pain scores. However, patients in the lavender group reported a higher satisfaction rate with pain control than patients in the control group (P = 0.0001).
Relaxor Behavior of the 0.9BaTiO3–0.1La(Mg1/2Ti1/2)O3 Solid Solution
Authors: Salak Andrei N. , Seabra Maria Paula , Ferreira Victor M.
Published: November 2006

Low‐frequency dielectric response of air‐ and oxygen‐sintered ceramics with the composition 0.9BaTiO3–0.1La(Mg1/2Ti1/2) O3 (0.9BT–0.1LMT) has been studied in the temperature range of 12–550 K. In comparison with pure BT, in 0.9BT–0.1LMT the dielectric permittivity maximum is shifted by almost 300 K toward lower temperatures. Both real and imaginary parts of dielectric permittivity of the solid solution, in the range 12–150 K, show a strong frequency‐dependent behavior, which is typical of relaxors. On the basis of the model of exponential cluster size distribution and the Cole–Cole equation, the degree of interaction between the polar clusters was estimated. It was shown that the oxygen vacancies arising during sintering at high temperatures did not affect noticeably the relaxor properties of the material. The role of heterovalent La3+/Ba2+ and Mg2+/Ti4+ substitutions in the relaxor behavior formation is discussed.
Efficient assay for evaluating human thrombopoiesis using NOD/SCID mice transplanted with cord blood CD34+ cells
Authors: Suzuki Ken‐ichi , Hiramatsu Hidefumi , Fukushima‐Shintani Mari , Heike Toshio , Nakahata Tatsutoshi
Published: November 2006

A suitable model for the preclinical study of human platelet production in vivo has not been available. NOD/SCID mice were characterized as representing an efficient engraftment model for human hematopoietic stem cells, which resulted in the production of human platelets. Here, we evaluated in vivo human thrombopoiesis and ex vivo human platelet functions in NOD/SCID mice transplanted with human cord blood (CB) CD34+ cells. Human platelets and human CD45+ cells appeared in peripheral blood of NOD/SCID mice from 4 wk after transplantation. Human platelets produced in these mice showed CD62P expression and the activation of GPIIb/IIIa on human platelets on stimulation with an agonist. PEG‐rHuMGDF (0, 0.5 and 5 μg/kg/d s.c.) was injected for 14 d into mice that had been confirmed to produce human platelets stably. The number of human platelets increased about twofold at 0.5 μg/kg/d and about fivefold at 5 μg/kg/d after 14 d. Withdrawal of PEG‐rHuMGDF administration caused the human platelet count to return to the pretreatment level. Further, re‐administration of PEG‐rHuMGDF induced a similar human thrombopoietic response as it did on initial administration. These results suggest that NOD/SCID mice engrafted with human CB CD34+ cells will be useful for the study of human platelet production in vivo.
Does an immunochromatographic D‐dimer exclude acute lower limb deep venous thrombosis?
Authors: Subramaniam Rathan M , Heath Rebekah , Cox Kim , Chou Tina , Stewart Joanna , Sleigh Jamie
Published: November 2006

Background:  A pre‐test probability score and D‐dimer may reduce the need for ultrasound examinations for excluding lower limb deep venous thrombosis (DVT).

Objective:  To establish the accuracy of an immunochromatographic D‐dimer assay called ‘Simplify’ for diagnosis of acute DVT by complete (calf veins included) lower limb ultrasound examination.

Methods:  A total of 453 consecutive patients presented to the ED of a tertiary centre with suspected first episode of DVT, were prospectively recruited. A pre‐test probability score (Hamilton Score), an immunochromatographic D‐dimer and a complete, single, unilateral lower limb ultrasound examination were performed in all patients. All patients with a negative ultrasound examination were followed up for 3 months.

Results:  There were 159 men and 294 women with a mean age of 55.8 years (SD 20.3). Of the 227 patients with a negative D‐dimer, 214 patients had negative ultrasound examinations and 13 patients had isolated calf DVT. Among the 226 patients with a positive D‐dimer, 74 patients had DVT and 152 patients had negative ultrasound examinations. The sensitivity, specificity, positive and negative predictive values were 85.1% (75.8–91.8), 58.5% (53.4–63.5), 32.7% (26.6–38.9) and 94.3% (90.4–96.9), respectively. One hundred and sixty‐five patients had an unlikely Hamilton Score and a negative D‐dimer. The negative predictive value of the immunochromatographic D‐dimer in an unlikely Hamilton Score population was 98.8% (95.7–99.8%).

Conclusion:  An unlikely probability Hamilton Score and a negative immunochromatographic D‐dimer reliably exclude both proximal and isolated calf DVT.
Patients Responding to Phosphodiesterase Type 5 Inhibitor Therapy—What Do Their Sexual Partners Know?
Authors: Klotz Theodor , Mathers Mike , Klotz Rosemarie , Sommer Frank
Published: November 2006

Introduction

Phosphodiesterase type 5 (PDE5) inhibitors are an efficacious therapy in men with erectile dysfunction (ED). There are only a few studies that also focus on the participating couples during PDE5 inhibitor therapy.

Aim

To determine to what extent patients personally informed their sexual partners about their ongoing PDE5 inhibitor therapy.

Main Outcome Measures

Likelihood of informing the female partner by the patient himself about the use of PDE5 inhibitors.

Methods

A total of 216 men (mean age 62.3 years) with ED were successfully treated with PDE5 inhibitors in three independent centers. After an interval of at least 3 months of successful ED therapy, all patients were asked by questionnaire whether their sexual partners were informed of their PDE5 inhibitor therapy.

Results

Eighty-two percent of the patients were exclusively involved in one stable sexual relationship, 9.7% of the men admitted to having changing sexual partners, and 6% did not give any information at all about their sexual partners. Twenty percent of the men had a severe ED (International Index of Erectile Function [IIEF-5] <11). Forty-nine percent showed a moderate ED (IIEF-5 11–16) and 31% suffered a mild ED (IIEF-5 >16). PDE5 inhibitor medication was used 1.2 times/month by men with a severe ED, 2.1 times/month by patients with a moderate ED, and 2.9 times/month by men with a mild ED. Forty-one (93%) of the 44 patients with a severe ED informed their sexual partners that they were taking PDE5 inhibitors. In the patient group with moderate ED, 49 (47%) of 105 patients and only 14 (21%) of 67 of the patients with mild ED shared this information with their partners.

Conclusion

Less than 40% of the patients suffering a moderate or mild ED using PDE5 inhibitors shared this information with their partners. It seems that patients find ED so disturbing that many patients do not inform their partners of PDE5 inhibitor use.
Optimized radiographic spectra for small animal digital subtraction angiography
Authors: De Lin Ming , Samei Ehsan , Badea Cristian T. , Yoshizumi Terry T. , Allan Johnson G.
Published: November 2006

The increasing use of small animals in basic research has spurred interest in new imaging methodologies. Digital subtraction angiography (DSA) offers a particularly appealing approach to functional imaging in the small animal. This study examines the optimal x‐ray, molybdenum (Mo) or tungsten (W) target sources, and technique to produce the highest quality small animal functional subtraction angiograms in terms of contrast and signal‐difference‐to‐noise ratio squared . Two limiting conditions were considered—normalization with respect to dose and normalization against tube loading. Image contrast and were simulated using an established x‐ray model. DSA images of live rats were taken at two representative tube potentials for the W and Mo sources. Results show that for small animal DSA, the Mo source provides better contrast. However, with digital detectors, is the more relevant figure of merit. The W source operated at achieved a higher . The highest was obtained at voltages above . However, operation at the higher potential results in significantly greater dose and tube load and reduced contrast quantization. A reasonable tradeoff can be achieved at tube potentials at the beginning of the performance plateau, around , where the relative gain in is the greatest.