bluuebunny/crossref_metadata_2025_split huggingface dataset:
GPRC6A regulates prostate cancer progression
Authors: Pi Min , Quarles L. Darryl 
Published: June 2011

AbstractBACKGROUNDGPRC6A is a nutrient sensing GPCR that is activated in vitro by a variety of ligands, including amino acids, calcium, zinc, osteocalcin (OC), and testosterone. The association between nutritional factors and risk of prostate cancer, the finding of increased expression of OC in prostate cancer cells, and the association between GPRC6A and risk of prostate cancer in Japanese men implicates a role of GPRC6A in prostate cancer.METHODSWe examined if GPRC6A is expressed in human prostate cancer cell lines and used siRNA‐mediated knockdown GPRC6A expression in prostate cancer cells to explore the function of GPRC6A in vitro. To assess the role of GPRC6A in prostate cancer progression in vivo, we intercrossed Gprc6a−/− mice onto the TRAMP mouse prostate cancer model.RESULTSGPRC6A transcripts were markedly increased in prostate cancer cell lines 22Rv1, PC‐3, and LNCaP, compared to the normal prostate RWPE‐1 cell line. In addition, a panel of GPRC6A ligands, including calcium, OC, and arginine, exhibited in prostate cancer cell lines a dose‐dependent stimulation of ERK activity, cell proliferation, chemotaxis, and prostate specific antigen and Runx2 gene expression. These responses were inhibited by siRNA‐mediated knockdown of GPRC6A. Finally, transfer of Gprc6a deficiency onto a TRAMP mouse model of prostate cancer significantly retarded prostate cancer progression and improved survival of compound Gprc6a−/−/TRAMP mice.CONCLUSIONSGPRC6A is a novel molecular target for regulating prostate growth and cancer progression. Increments in GPRC6A may augment the ability of prostate cancer cells to proliferate in response to dietary and bone derived ligands. Prostate 72:399–409, 2012. © 2011 Wiley Periodicals, Inc.
Effects of glycosylation on heparin binding and antithrombin activation by heparin
Authors: Pol‐Fachin Laercio , Franco Becker Camila , Almeida Guimarães Jorge , Verli Hugo 
Published: June 2011

AbstractAntithrombin (AT), a serine protease inhibitor, circulates in blood in two major isoforms, α and β, which differ in their amount of glycosylation and affinity for heparin. After binding to this glycosaminoglycan, the native AT conformation, relatively inactive as a protease inhibitor, is converted to an activated form. In this process, β‐AT presents the higher affinity for heparin, being suggested as the major AT glycoform inhibitor in vivo. However, either the molecular basis demonstrating the differences in heparin binding to both AT isoforms or the mechanism of its conformational activation are not fully understood. Thus, the present work evaluated the effects of glycosylation and heparin binding on AT structure, function, and dynamics. Based on the obtained data, besides the native and activated forms of AT, an intermediate state, previously proposed to exist between such conformations, was also spontaneously observed in solution. Additionally, Asn135‐linked oligosaccharide caused a bending in AT‐bounded heparin, moving such polysaccharide away from helix D, which supports its reduced affinity for α‐AT. The obtained data supported the proposal of an atomic‐level, solvent and amino acid residues accounting, putative model for the transmission of the conformational signal from heparin binding exosite to β‐sheet A and the reactive center loop, also supporting the identification of differences in such transmission between the serpin glycoforms involving helix D, where the Asn135‐linked oligosaccharide stands. Such intramolecular rearrangements, together with heparin dynamics over AT surface, may support an atomic‐level explanation for the Asn135‐linked glycan influence over heparin binding and AT activation. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Spinosad resistance in female Musca domestica L. from a field‐derived population
Authors: Markussen Mette DK , Kristensen Michael 
Published: June 2011

AbstractBACKGROUND: Bait‐formulated spinosad is currently being introduced for housefly (Musca domestica L.) control around the world. Spinosad resistance was evaluated in a multiresistant field population and strains derived from this by selection with insecticides. Constitutive and spinosad‐induced expression levels of three cytochrome P450 genes, CYP6A1, CYP6D1 and CYP6D3, previously reported to be involved in insecticide resistance, were examined.RESULTS: In 2004 a baseline for spinosad toxicity of Danish houseflies where all field populations were considered to be susceptible was established. In the present study, females of a multiresistant field population 791a were, however, 27‐fold spinosad resistant at LC50, whereas 791a male houseflies were susceptible. Strain 791a was selected with spinosad, thiamethoxam, fipronil and imidacloprid, resulting in four strains with individual characteristics. Selection of 791a with spinosad did not alter spinosad resistance in either males or females, but counterselected against resistance to the insecticides thiamethoxam and imidacloprid targeting nicotinic acetylcholine receptors. A synergist study with piperonyl butoxide, as well as gene expression studies of CYP6A1, CYP6D1 and CYP6D3, indicated a partial involvement of cytochrome P450 genes in spinosad resistance.CONCLUSION: This study reports female‐linked spinosad resistance in Danish houseflies. Negative cross‐resistance was observed between spinosad and neonicotinoids in one multiresistant housefly strain. Spinosad resistance involved alterations of cytochrome P450 gene expression. Copyright © 2011 Society of Chemical Industry
Ammonothermal GaN substrates: Growth accomplishments and applications
Authors: Dwiliński Robert , Doradziński Roman , Garczyński Jerzy , Sierzputowski Leszek , Kucharski Robert , Zając Marcin , Rudziński Mariusz , Kudrawiec Robert , Strupiński Włodzimierz , Misiewicz Jan 
Published: June 2011

AbstractWe are presenting some physical and chemical basis of ammonothermal method of bulk gallium nitride (GaN) synthesis in ammonobasic route. The substrates of polar, non‐polar, and semi‐polar orientation can be obtained by this method. Excellent structural and wide spectrum of electrical parameters of truly bulk GaN crystals obtained this way are revealed. Large progress in manufacturing of large size (1‐in.) non‐polar ammonothermal crystals is reported. A preliminary results on performance of the devices grown on ammonothermal GaN substrates will be shown.
AC conductivity and dielectric spectroscopic studies of polypyrrole–titanium dioxide hybrid nanocomposites
Authors: Kumar A. , Sarmah S. 
Published: June 2011

AbstractDielectric spectroscopy and AC conductivity measurements have been employed to investigate the electrical properties of disordered materials in a wide range of temperature. In this work, conducting polypyrrole–titanium dioxide (PPy–TiO2) hybrid nanocomposites have been synthesized by oxidizing pyrrole in presence of different concentration (wt%) of TiO2 nanoparticles. Thermal stability of the nanocomposites increases with the increase in TiO2 wt%. The dielectric and electric modulus studies of as prepared samples were carried out over a frequency range of 42 Hz–5 MHz. The dielectric constant and dielectric loss for all the nanocomposite samples were observed to decrease with the increase of frequency. Electric modulus analysis has been carried out to understand the electrical relaxation processes. The dielectric relaxation time of nanocomposites decreases with the increase of TiO2 nanoparticles concentration. AC conductivity measurements show that correlated barrier hopping conduction mechanism can be employed for pure PPy and PPy‐5 wt% TiO2 nanocomposites, whereas large polaron tunnelling mechanism is applicable for higher concentration of TiO2 (10–25 wt%) in PPy–TiO2 nanocomposites.
Preparation and optical characterization of PbCl2–Sb2O3–TeO2 glasses doped with rare earth elements
Authors: Kostka Petr , Zavadil Jiri , Pedlikova Jitka , Poulain Marcel 
Published: June 2011

AbstractGlasses in the PbCl2–Sb2O3–TeO2 ternary system were prepared, characterized and their characteristic temperatures and glass stability were determined by thermal analysis. The most stable glass compositions were found in the TeO2 rich area of the ternary diagram. Selected glass compositions from this group were doped with Er3+, Nd3+ or Pr3+ ions. Changes in composition during the melting process were investigated, and the chemical analysis was performed using an electron microscope coupled with an EDS analyser. Optical characterizations include the transmission spectroscopy and low temperature photoluminescence (PL) measurements. The studied glasses are transparent up to 80%, and their transparency region falls between 400 nm and 6 µm. The refraction index was found to be around 2.2. A broad band centred around 970 nm was observed in the PL spectra of base glass systems. Rare earth doped samples exhibit all absorption bands in the investigated region of spectra (300–1100 nm) and also emission peaks in the range of 800–1800 nm. The re‐absorption of base glass luminescence, in the case of Er3+ doped samples, was observed at low temperature and it correlates well with 4I11/2 → 4I15/2 transition at 980 nm. The re‐absorption effect disappears above 200 K.
Surface photovoltage within a monolayer of CdSe quantum dots
Authors: Zillner Elisabeth , Dittrich Thomas 
Published: June 2011

AbstractLayers of pyridine terminated CdSe quantum dots (QDs) with thicknesses from a monolayer (ML) to 80 nm were deposited on ITO substrates by dip coating. Transient surface photovoltage measurements showed dominant charge separation within the first ML of QDs at short times and an increasing influence of layer thickness at long times. Auger recombination limited the maximum of separated charge carriers to about 1 × 1012 cm‐2.magnified imageSeparation of photo‐generated electron‐hole pairs within a ML of CdSe‐QDs. Electrons were either trapped on ITO surface states or separated due to a built‐in electrical field created by a transferred electron from the ITO to a trap state at the QD. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A DFT study on the structure‐property relationship of aminonitropyrazole‐2‐oxides
Authors: Ravi P. , Gore Girish M. , Sikder Arun K. , Tewari Surya P. 
Published: June 2011

AbstractDensity functional theory (DFT) calculations at the B3LYP/aug‐cc‐pVDZ level have been carried out to study the geometry and electronic structures, stability, sensitivity and band gap of the possible isomers of aminonitropyrazole‐2‐oxides. Kamlet‐Jacob equations were used to determine the performance properties of model compounds. The performance properties of model compounds P5, P18, P20, P21, P22, and P23 are higher compared with 2,4,6,8,10,12‐hexanitro‐2,4,6,8,10,12‐hexaazaisowurtzitane (CL‐20) and octanitrocubane (ONC). The heat of explosion, density, detonation velocity and detonation pressure are related to the number and positions of NO2 and NH2 groups in pyrazole‐2‐oxide. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012
Scanning Tunneling Luminescence of Individual CdSe Nanowires
Authors: Lutz Theresa , Kabakchiev Alexander , Dufaux Thomas , Wolpert Christian , Wang Zhe , Burghard Marko , Kuhnke Klaus , Kern Klaus 
Published: June 2011

AbstractThe local luminescence properties of individual CdSe nanowires composed of segments of zinc blende and wurtzite crystal structures are investigated by low‐temperature scanning tunneling luminescence spectroscopy. Light emission from the wires is achieved by the direct injection of holes and electrons, without the need for coupling to tip‐induced plasmons in the underlying metal substrate. The photon energy is found to increase with decreasing wire diameter due to exciton confinement. The bulk bandgap extrapolated from the energy versus diameter dependence is consistent with photon emission from the zinc blende‐type CdSe sections.
Plasmonic Nickel Nanoantennas
Authors: Chen Jianing , Albella Pablo , Pirzadeh Zhaleh , Alonso‐González Pablo , Huth Florian , Bonetti Stefano , Bonanni Valentina , Åkerman Johan , Nogués Josep , Vavassori Paolo , Dmitriev Alexandre , Aizpurua Javier , Hillenbrand Rainer 
Published: June 2011

AbstractThe fundamental optical properties of pure nickel nanostructures are studied by far‐field extinction spectroscopy and optical near‐field microscopy, providing direct experimental evidence of the existence of particle plasmon resonances predicted by theory. Experimental and calculated near‐field maps allow for unambiguous identification of dipolar plasmon modes. By comparing calculated near‐field and far‐field spectra, dramatic shifts are found between the near‐field and far‐field plasmon resonances, which are much stronger than in gold nanoantennas. Based on a simple damped harmonic oscillator model to describe plasmonic resonances, it is possible to explain these shifts as due to plasmon damping.
Re‐centring capacity of dual‐steel frames
Authors: Dubina Dan , Stratan Aurel , Dinu Florea 
Published: June 2011

AbstractCapacity design principles used in modern seismic design codes are deemed to confine plastic deformations to dissipative elements only. In conventional structures, this can be undesirable as the plastic deformations mean damage to structural elements, interruption to building operations and substantial repair works. If these elements are removable and can be replaced, the structure has the ability to return to the initial undeformed shape after an earthquake, provided restoring forces are supplied by part of the structure still within the elastic range. The objective of the present work, which continues the previous research of the authors, is to present a general methodology for designing structures with removable dissipative elements and re‐centring capability. Two applications are also presented.
Punch Problem for Planar Anisotropic Elastic Half-Plane
Authors: Lin R.-L. 
Published: June 2011

ABSTRACTThe two dimensional punch problem for planar anisotropic elastic half-plane is revisited using the Lekhnitskii's formulation with aid of the Fourier transform and boundary integral equation. Four different conditions of contact problem for the rigid punch are analyzed in this study. From the combination of surface Green's function of half-plane and Hooke's law of anisotropic material, a set of Fredholm integral equations are obtained for mixed boundary value problems. After solving the integral equation according to specified contact condition, the explicit distributions of surface traction under the punch are obtained in closed-form. From the surface traction and Green's function of anisotropic half-plane, the full-field solutions of stresses are constructed. Numerical calculations of surface traction under the rigid punch are presented base on the analysis and are discussed in detail.
On the Use of Temporal Reachout Technique for Characteristics Method with Time-Line Cubic Spline Interpolation
Authors: Tsai T.-L. , Chen J.-Y. 
Published: June 2011

ABSTRACTThe study had indicated that the computational performances of the characteristics method with the time-line cubic spline interpolation are related to the endpoint constraint, especially for large Courant number in which the foot of the characteristic trajectory is located near the endpoint. The first derivative endpoint constraint with higher-order central difference approximation provides better simulation results among various endpoint constraints, but it still induces some degree of numerical error. In this study, by locating the foot of the characteristic trajectory away from the endpoint, the temporal reachout technique is proposed to avoid the effect of endpoint constraint on the time-line cubic spline interpolation. Modeling the transport of a Gaussian concentration distribution in a uniform flow with constant diffusion coefficient and the viscous Burgers equation is used to examine the temporal reachout technique. The outcomes show that the temporal reachout technique yields much better simulation results than the first derivative endpoint constraint with higher-order central difference approximation. The effect of endpoint constraint on the time-line cubic spline interpolation can be greatly diminished by the use of the temporal reachout technique.
ON A PROBLEM ON NORMAL NUMBERS RAISED BY IGOR SHPARLINSKI
Authors: DE KONINCK JEAN-MARIE , KÁTAI IMRE 
Published: June 2011

AbstractGiven an integer d≥2, a d-normal number, or simply a normal number, is an irrational number whosed-ary expansion is such that any preassigned sequence, of length k≥1, taken within this expansion occurs at the expected limiting frequency, namely 1/dk. Answering questions raised by Igor Shparlinski, we show that 0.P(2)P(3)P(4)…P(n)… and 0.P(2+1)P(3+1)P(5+1)…P(p+1)…, where P(n) stands for the largest prime factor of n, are both normal numbers.
Triple manifestation of extramedullary plasmacytoma in the upper airway: an unusual clinical entity
Authors: Morariu I , Burns P , Roche P , Hone S 
Published: June 2011

AbstractObjective:We report an extremely rare case of extramedullary plasmacytoma.Method:Case report and review of the English-literature concerning extramedullary plasmacytoma and multiple myeloma.Result:We present an unusual case of multiple extramedullary plasmacytomas, which, over a protracted course of 30 years, presented on different occasions at three separate sites in the head and neck. The patient was managed surgically on all occasions, and was disease-free at the time of writing.Conclusion:Following review of the literature, we believe this to be the only case with this extremely unusual presentation. This case is noteworthy, not only because of the rarity of extramedullary plasmacytoma, but also because it highlights a number of important clinical issues. The diagnosis and management of extramedullary plasmacytoma require close cooperation between multiple disciplines.
Environmental and genetic pathways between early pubertal timing and dieting in adolescence: distinguishing between objective and subjective timing
Authors: Harden K. P. , Mendle J. , Kretsch N. 
Published: June 2011

BackgroundEarly pubertal timing in girls is associated with elevated risk for dieting and eating pathology. The relative importance of biologicalversussocio-environmental mechanisms in explaining this association remains unclear. Moreover, these mechanisms may differ between objective measures of pubertal development and girls' subjective perceptions of their own maturation.MethodThe sample comprised 924 sister pairs from the National Longitudinal Study of Adolescent Health. Objective pubertal timing (menarcheal age), girls' perceptions of pubertal status and timing relative to peers, dieting and disordered eating behaviors were assessed during a series of confidential in-home interviews.ResultsBehavioral genetic models indicated that common genetic influences accounted for the association between early menarcheal age and increased risk for dieting in adolescence. In contrast, girls' subjective perceptions of their timing relative to peers were associated with dieting through an environmental pathway. Overall, subjective and objective measures of pubertal timing accounted for 12% of the variance in dieting.ConclusionsGenetic differences in menarcheal age increase risk for dieting among adolescent girls, while girls' perceptions of their maturation represent an environmentally mediated risk.
Relativistic guidance of an intense laser beam through an axially non-uniform plasma channel
Authors: Singh Arvinder , Singh Navpreet 
Published: June 2011

AbstractThe effect of relativistic nonlinearity on the guiding of a laser beam in a plasma channel formed by a short ionizing pulse is investigated. The plasma channel formed is axially non-uniform due to self defocusing of the prepulse. When a second delayed laser pulse propagates through the plasma channel formed by the prepulse, the competition between refraction and diffraction results into alternate convergence and divergence of the guided beam. Second-order nonlinear differential equations for the beam width parameter of the prepulse and guided pulse are derived by moment theory approach. The effect of the guided pulse intensities as well as the axial nonuniformity of the plasma channel on the propagation of the guided laser pulse has been investigated. Relativistic laser guidance up to several Rayleigh lengths is observed.
Angular Dependence of the Ion-Induced Secondary Electron Emission for He+ and Ga+ Beams
Authors: Castaldo Vincenzo , Withagen Josephus , Hagen Cornelius , Kruit Pieter , van Veldhoven Emile 
Published: June 2011

AbstractIn recent years, novel ion sources have been designed and developed that have enabled focused ion beam machines to go beyond their use as nano-fabrication tools. Secondary electrons are usually taken to form images, for their yield is high and strongly dependent on the surface characteristics, in terms of chemical composition and topography. In particular, the secondary electron yield varies characteristically with the angle formed by the beam and the direction normal to the sample surface in the point of impact. Knowledge of this dependence, for different ion/atom pairs, is thus the first step toward a complete understanding of the contrast mechanism in scanning ion microscopy. In this article, experimentally obtained ion-induced secondary electron yields as a function of the incidence angle of the beam on flat surfaces of Al and Cr are reported, for usual conditions in Ga+ and He+ microscopes. The curves have been compared with models and simulations, showing a good agreement for most of the angle range; deviations from the expected behavior are addressed and explanations are suggested. It appears that the maximum value of the ion-induced secondary electron yield is very similar in all the studied cases; the yield range, however, is consistently larger for helium than for gallium, which partially explains the enhanced topographical contrast of helium microscopes over the gallium focused ion beams.
A dynamic analysis of the effects on pensioners’ welfare of social security reforms
Authors: PEINADO PATRICIA , SERRANO FELIPE 
Published: June 2011

AbstractThe aim of this paper is to analyze the dynamic effects of the different parametric reforms oriented to reach the financial balance of public pension systems on the well-being of the retired population. Using the Spanish social security system as a case study, a duration analysis is implemented to look for a causal relationship and then estimate separately the effects of an effective retirement age delay and a replacement rate reduction as well as the combined effect of these two measures. We also estimate the effects of a delay on the reforms. We find that a change in the effective retirement age would have positive effects on the individual welfare of retired population, while a reduction of the replacement rate would diminish it. The combined effect of the two measures would finally translate into a welfare lost of the retired population. The delay on the reforms implies higher welfare loss (to the affected generations) than the analyzed reforms.
Profitability of pension contributions – evidence from real-life employment biographies
Authors: SCHRÖDER CARSTEN 
Published: June 2011

AbstractMicro-econometric intra-cohort profitability analyses of pay-as-you-go (PAYG) pension contributions are rare. We use representative employment histories of German PAYG pension insurants retiring in year 2005 to examine the determinants of the profitability of contributions using nominal internal rates of return (IRR) as measure. When future nominal pension entitlements are frozen at today's level, average IRR is about three percent. It increases in beneficiaries' remaining life expectancies at retirement and in the length of non-contribution periods resulting, for example, from child care. Interestingly, IRR is decreasing in insurants' earnings capacity, indicating that the system entails an intra-cohort progressive element.