bluuebunny/crossref_metadata_2025_split huggingface dataset:
Beta‐2‐microglobulin expression correlates with high‐grade prostate cancer and specific defects in androgen signaling
Authors: Mink Sheldon R. , Hodge Amanda , Agus David B. , Jain Anjali , Gross Mitchell E. 
Published: March 2010

AbstractBACKGROUNDPreviously, we identified Beta‐2‐microglobulin (β2M) as an androgen‐regulated secreted protein elevated in the serum of prostate cancer patients. In this study, we explore an interaction between β2M expression, prostate cancer tissue, and the androgen signaling axis.METHODSβ2M expression in relation to clinical and pathologic variables was examined in a tissue microarray representing specimens obtained at the time of radical prostatectomy. Viral vectors were designed to down‐regulate β2M expression, and the effects on androgen‐dependent growth, transcriptional regulation, and androgen receptor recruitment was investigated in human prostate cancer cell lines.RESULTSVariation in β2M expression in human prostate cancer is associated with characteristics of clinically aggressive disease such as high tumor grade. Knockdown of β2M expression in human prostate cancer cells resulted in selective defects in androgen‐dependent events including growth, gene regulation, and chromatin assembly.CONCLUSIONSβ2M expression may provide prognostic information in patients treated with surgery for prostate cancer. Targeting β2M expression or activity may represent a new and important mechanism to manipulate the androgen signaling axis in patients with prostate cancer. Prostate 70: 1201–1210, 2010. © 2010 Wiley‐Liss, Inc.
Electrochemical preparation of MoO3 buffer layer deposited onto the anode in organic solar cells
Authors: Gacitua M. , Boutaleb Y. , Cattin L. , Abe S. Yapi , Lare Y. , Soto G. , Louarn G. , Morsli M , Rehamnia R. , del Valle M. A. , Drici A. , Bernède J. C. 
Published: March 2010

AbstractIn this work the authors have studied the advantages of using electrochemically deposited molybdenum oxide as a buffer layer in an organic bilayer heterojunction solar cell arrangement. Furthermore, it has been probed that electrochemistry provides an alternative low cost, reproducible and less laborious method to prepare thin layered deposits. The precursor solution is composed by a concentrated molybdic acid solution in a sulphuric media in order to ensure the obtainment of low reduced molybdenum species. Therefore, by means of potentiostatic techniques, ITO/molybdenum oxide transparent anodes were tested for the photovoltaic device showing improved surface properties. XDR and AFM techniques were used to characterize the morphology of the deposits. The films with optimum thickness (5 nm) are amorphous. XPS analysis indicates that the best results in solar cell performance are in hand with a heterogeneous composition of the molybdenum oxide film presenting MoV and MoVI as predominant species. The MoO3 films deposited by cyclic voltammetry are not as homogeneous as those deposited by potentiostatic technique and only MoVI species are present. These differences may justify the different behaviour of the solar cells using these different buffer layers. Only buffer layers deposited by potentiostatic technique allow improving the cells performances in the same way than those achieved by evaporation.
A MIP‐based biomimetic sensor for the impedimetric detection of histamine in different pH environments
Authors: Bongaers E. , Alenus J. , Horemans F. , Weustenraed A. , Lutsen L. , Vanderzande D. , Cleij T. J. , Troost F. J. , Brummer R.‐J. , Wagner P. 
Published: March 2010

AbstractThe development of novel biosensors is a rapidly growing field. Substituting the biological receptor layer from the biosensor with a synthetic receptor opens the door for the development of biomimetic sensors that are chemically and physically inert, as opposed to the sensors containing biological recognition elements. Using molecularly imprinted polymers (MIPs) the specificity and affinity of biological receptors can be mimicked. In addition, a MIP‐based sensor can measure in harsh environments. Histamine occurs in harsh environments in food and bodily fluids and is chosen as the target molecule for impedimetric detection. When 10 nM histamine is present in pH neutral environments, the impedance increases 45% with respect to the impedance of the sensor without histamine. Specificity is tested with respect to histidine. The influence of the pH on the performance of the sensor is tested. In a pH range of pH 5–12 the MIPs are stable, although they exhibit a varying degree of protonation. The same holds true for the target molecule of which the protonation also varies with the pH of the solution. It is shown that the pH dependent degree of protonation of both the MIP and the histamine has a large impact on the binding of histamine to the nanocavity in the MIP. Hence, the detection of histamine by a MIP‐based sensor is affected by the pH of the solution.
Gas sensor investigation based on a catalytically activated thin‐film thermopile for H2O2 detection
Authors: Kirchner Patrick , Ng Yue Ann , Spelthahn Heiko , Schneider Andreas , Henkel Hartmut , Friedrich Peter , Kolstad Jens , Berger Jörg , Keusgen Michael , Schöning Michael J. 
Published: March 2010

AbstractIn aseptic filling systems, hydrogen peroxide vapour is commonly used for the reduction of microbial contaminations in carton packages. In this process, the germicidal efficiency of the vapour depends especially on the H2O2 concentration. To monitor the H2O2 concentration, a calorimetric H2O2 gas sensor based on a catalytically activated thin‐film thermopile is investigated. Two different sensor layouts, namely a circular and a linear form, as well as two various material pairs such as tungsten/nickel and gold/nickel, have been examined for the realization of a thin‐film thermopile. Additionally, manganese oxide and palladium particles have been compared as responsive catalysts towards H2O2. The thin‐film sensors have been investigated at various H2O2 concentrations, gas temperatures and flow rates.
Co‐adsorption processes, kinetics and quantum mechanical modelling of nanofilm semiconductor gas sensors
Authors: Velasco‐Vélez Juan‐Jesús , Kunze Ulrich , Haas Thomas , Doll Theodor 
Published: March 2010

AbstractA quantum mechanical model of co‐adsorption on semiconductor surfaces is developed and successfully adopted towards exposure to several gases. It is related to nanofilms and thus allows the application of electric fields altering the electronic surface properties of adsorption centres (electroadsorptive effect, EAE). The model is matched against experimental data with O2, NO2 and CO measurements under the hypothesis of no direct interaction among the species. However the sequence of adsorption plays an important role where the adsorption of one gas species is opening up other sites that are filled by another sort of impinging molecules. Quantum mechanical modelling of co‐adsorption: (a) NO2 and CO present at the SnO2 surface. (b) Simplified model. (c) Probability of adsorption. magnified image
Finite element simulation of the optical modes of semiconductor lasers
Authors: Pomplun Jan , Burger Sven , Schmidt Frank , Schliwa Andrei , Bimberg Dieter , Pietrzak Agnieszka , Wenzel Hans , Erbert Götz 
Published: March 2010

AbstractIn the present paper we investigate optical near fields in semiconductor lasers. We perform finite element simulations for two different laser types, namely a super large optical waveguide (SLOW) laser, which is an edge emitter, and a vertical cavity surface emitting laser (VCSEL). We give the mathematical formulation of the different eigenvalue problems that arise for our examples and explain their numerical solution with the finite element method (FEM). Thereby, we also comment on the usage of transparent boundary conditions, which have to be applied to respect the exterior environment, e.g., the very large substrate and surrounding air. For the SLOW laser we compare the computed near fields to experimental data for different design parameters of the device. For the VCSEL example a comparison to simplified 1D mode calculations is carried out.
Pre‐requisites for the formation of unusual diffusion profiles in II–VI semiconductors
Authors: Wolf H. , Kronenberg J. , Wagner F. , Wichert Th. 
Published: March 2010

AbstractThe diffusion of the impurities Cu, Ag, Au, and Na in CdTe and CdZnTe exhibits the unusual phenomenon of uphill diffusion if the diffusion of the impurity is performed under external Cd pressure at temperatures typically in the range 700–900 K. A model is proposed that describes these concentration profiles quantitatively and yields pre‐requisites for the observation of uphill diffusion. If a metal layer is evaporated onto the implanted surface, the diffusion of the impurity is strongly affected by the generation of intrinsic defects at the metal–semiconductor interface.
Density‐functional study on the migration of Cd and Te adsorbates on the (001) surface of CdTe
Authors: Patrakov Anatoly E. , Fink Reinhold F. , Fink Karin , Schmidt Thomas C. , Engels Bernd 
Published: March 2010

AbstractWe present a density‐functional study on the mobility of cadmium (Cd) and tellurium (Te) adsorbate atoms on the reconstructed Te‐terminated (001) CdTe (2 × 1) surface. Two‐dimensional potential energy surfaces as a function of the position of the adsorbate atom on the surface were calculated. For Cd as well as Te adsorption, two potential minima were found. The binding energies amount to −2. and −0.71 eV for Cd (−2.8 and −1.4 eV for Te). At any position of the surface, Te adsorption is found to be stronger than that of Cd. Our results indicate that an adsorption of a Te atom at the reconstructed Te‐terminated (001) CdTe (2 × 1) surface leads to adsorbates which may move along the surface due to their thermal energy. In the opposite, Cd adsorbate atoms are essentially trapped in the global minimum and desorption is expected to be much more likely than motion along the surface.
On the solution‐space geometry of random constraint satisfaction problems
Authors: Achlioptas Dimitris , Coja‐Oghlan Amin , Ricci‐Tersenghi Federico 
Published: March 2010

AbstractFor various random constraint satisfaction problems there is a significant gap between the largest constraint density for which solutions exist and the largest density for which any polynomial time algorithm is known to find solutions. Examples of this phenomenon include random k‐SAT, random graph coloring, and a number of other random constraint satisfaction problems. To understand this gap, we study the structure of the solution space of random k‐SAT (i.e., the set of all satisfying assignments viewed as a subgraph of the Hamming cube). We prove that for densities well below the satisfiability threshold, the solution space decomposes into an exponential number of connected components and give quantitative bounds for the diameter, volume, and number.© 2010 Wiley Periodicals, Inc. Random Struct. Alg., 38, 251–268, 2011
Eco‐clothing, consumer identity and ideology
Authors: Niinimäki Kirsi 
Published: March 2010

AbstractThis paper aims to contribute to a better understanding of eco‐fashion consumption and consumer purchase decisions while constructing one's self with external symbols, such as appearance, clothing and fashion items. This study approaches sustainable clothing from a grounding in design research and the meanings of material culture. The study uses sociology and social psychology; hence, the meaning of appearance and especially clothing and fashion is understood in a social context. This paper also takes an interdisciplinary approach to eco‐clothes as cultural and design objects in a social and sustainable development context, objects that intertwine consumers' ethical attitudes and values and how they construct a concept of ‘self’ using external symbols. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment.
Molecular depth profiling of polymers with very low energy reactive ions
Authors: Houssiau L. , Mine N. 
Published: March 2010

AbstractThis work follows previous studies in which we demonstrated the feasibility of molecular depth profiling with time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS), using a low‐energy Cs+ source for sputtering. Poly(methyl methacrylate) (PMMA), polycarbonate (PC) and polystyrene (PS) thin films were investigated with both 250 eV Cs+ and Xe+ ions with the aim of assessing the role of the ion's reactivity in polymer depth profiling. A more detailed analysis of PS layers was given, completed with X‐ray photoelectron spectroscopy (XPS) measurements, since this polymer is known to degrade rapidly under ion irradiation. Indeed, no depth profile is possible on PS with conventional polyatomic sources. The three polymers were amenable to depth profiling with low‐energy Cs+. On the other hand, they were quickly degraded by the low‐energy Xe+ beam, although some specific molecular ions remained detectable throughout the depth profile on PMMA. Sputtering yield measurements provided valuable information on the chemistry involved during the sputtering process: the sputtering yields measured on PMMA, with both Cs+ and Xe+, were much higher than on PC and PS, probably due to depolymerization processes. On PC and PS, the sputtering yield was much higher with Cs+ than with Xe+. This is due to an inhibition of the cross‐linking reactions by the implanted Cs atoms, leading to the formation of caesium carbides and anions. Low‐energy caesium depth profiling is successful, thanks to the combination of three factors: (i) low energy means less damage; (ii) Cs enhances the negative ionization; and (iii) the Cs reactivity hinders cross‐linking reactions. Copyright © 2010 John Wiley & Sons, Ltd.
The potential for the application of X‐ray photoelectron spectroscopy in forensic science
Authors: Watts John F. 
Published: March 2010

AbstractThe potential for the use of X‐ray photoelectron spectroscopy (XPS) in forensic science is reviewed. Taking as a starting point a series of examples and case histories, this review speculates on other areas where XPS may be able to make a contribution. The topics that are considered include chemical speciation of fingerprints, thin layers deposited on substrates as a result of explosions and/or fire, particulate materials and cosmetics and finally sequestration of marker elements and molecules on surfaces. It is concluded that XPS has much to offer the forensic science community, but investigations may be hampered by the need to compare specimens from crime scene with known standards. Until this issue is addressed, it is likely that XPS will continue to be used on an ad hoc basis for particularly challenging specimens in high‐profile cases. Copyright © 2010 John Wiley & Sons, Ltd.
Application of the XPS for Studying the Magnetic Moment of 3d Metals in Carbon–Metal Nanostructures
Authors: Shabanova I. N. , Terebova N. S. 
Published: March 2010

AbstractA promising trend in the development of methods for studying the electronic structure of a substance is using the methods based on the application of X‐ray photoelectron spectroscopy (XPS).In the present article, the change of the spin magnetic moment of the transition 3d metal atoms is studied in metal‐containing nanoscale structures based on the relationship between the spin magnetic moment and the ratio of the intensities of multiplet splitting maxima in 3s spectra of metals. Copyright © 2010 John Wiley & Sons, Ltd.
Structure and properties of nitrogen‐doped titanium dioxide thin films produced by reactive magnetron sputtering
Authors: Abadias G. , Paumier F. , Eyidi D. , Guérin P. , Girardeau T. 
Published: March 2010

AbstractIn modern purification techniques employing semiconductor‐mediated photo oxidation of toxic substances, TiO2 materials are the most widely used metal oxides due to their unique blend of properties. However, the band edge of these semiconductors lying in the ultraviolet (UV) region makes them rather inactive under visible light irradiation. Nitrogen‐doped titanium dioxide (N‐TiO2) is attracting a continuous attention because this doping generates states just above the valence band and consequently narrows the band gap of TiO2. The visible light activity of these materials mainly depends on the location of this impurity state and consequently on the microstructure of the (N‐TiO2) materials. The objective of this study is to investigate the correlations between the microstructure of these materials and their electronic and optical properties. The N‐TiO2 films have been produced by reactive magnetron sputtering of a titanium target under a mixture of argon, nitrogen and oxygen gases. The microstructure and chemical properties of the films have been investigated by X‐ray diffraction (XRD) and X‐ray photoelectron spectroscopy (XPS). Ellipsometry and reflection electron energy loss spectroscopy (REELS)have been used to study their electronic and optical properties. The influence of a post‐annealing at 550 °C on these different properties has been also investigated. Copyright © 2010 John Wiley & Sons, Ltd.
Oxide‐film growth kinetics on Zr(0001) and Zr(1010) single‐crystal surfaces
Authors: Bakradze Georgijs , Jeurgens Lars P. H. , Mittemeijer Eric J. 
Published: March 2010

AbstractThe growth kinetics of very thin (<10 nm) oxide films on Zr(0001) and Zr(1010) single‐crystalline surfaces was investigated by real‐time in situ spectroscopic ellipsometry (RISE). To this end, clean Zr(0001) and Zr(1010) surfaces were prepared under ultrahigh vacuum conditions by a cyclic treatment of ion sputtering and in vacuo annealing. The thus obtained bare Zr surfaces were subsequently exposed to O2 (g) in the temperature range of 300–450 K (at a partial oxygen pressure of 10−4 Pa) while monitoring the growth kinetics by RISE. Quantitative RISE analysis showed that the less densely packed Zr(1010) surface oxidizes more readily than the densely packed Zr(0001) surface. Copyright © 2010 John Wiley & Sons, Ltd.
Effect of oxygen plasma on surface properties and biocompatibility of PLGA films
Authors: Hasirci Nesrin , Endogan Tugba , Vardar Elif , Kiziltay Aysel , Hasirci Vasif 
Published: March 2010

AbstractIn this study, poly(D, L‐lactide‐co‐glycolide) (PLGA) films were prepared by solvent casting method and the surfaces of the films were modified by application of oxygen plasma. A radio frequency (RF) generator working at 13.56 MHz was used to create plasma, and powers at different levels changing between 20 and 300 W were applied. The variations in chemistry, topography and surface free energy (SFE) of the films were investigated by electron spectroscopy for chemical analysis (ESCA), atomic force microscopy (AFM) and goniometer, respectively. The cell–material interactions of the modified samples were evaluated by cell culture tests using 3T3 fibroblast cell line.As the applied power of the RF generator was increased from 20 to 300 W, the surface oxygen content (examined by ESCA) first increased up to 100 W, and then decreased mostly because of crosslink formation by elimination of oxygen. Surface roughness (examined by AFM) and hydrophilicity (examined by water contact angle measurements) increased parallel to the applied power. SFE and the basic component of SFE also increased while the acidic component did not show a significant change with power according to the geometric mean approach. In vitro material–cell interaction studies showed that oxygen plasma modification enhanced the cell attachment and cell proliferation on PLGA samples. Copyright © 2010 John Wiley & Sons, Ltd.
Surface analysis of SiO2‐like high‐barrier thin films for protection of silver artefacts
Authors: Angelini E. , Grassini S. , Ingo G. M. , Mombello D. , Fracassi F. , Palumbo F. 
Published: March 2010

AbstractSurface engineering has been explored using plasma enhanced chemical vapur deposition (PECVD) of SiO2‐like coatings on different metallic substrates in order to improve their resistance to corrosion. Specifically, the coatings have been deposited onto silver‐based alloys which are prone to unaesthetic tarnishing, by means of PECVD in radio frequency (RF) plasma fed with tetraetoxysilane/oxygen/argon mixture.Microchemical and microstructural characterization of the coatings has been carried out by means of X‐ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM) and field emission scanning electron microscopy (FESEM). The protective effectiveness against tarnishing of SiO2‐like layers has been evaluated by immersion tests in 0.1 M Na2S aerated solution at room temperature.It has been found that SiO2‐like coatings deposited by increasing the oxygen‐to‐monomer ratio in the feeding‐gas mixture and the input power density possess excellent barrier effects, and the coating adhesion increases if the deposition process is performed after a hydrogen plasma treatment. The protective effectiveness of PECVD coatings may be related to their barrier effect against the diffusion of water and other gaseous aggressive agents present in the environment and coming into contact with the metal surface. Copyright © 2010 John Wiley & Sons, Ltd.
Studies of laser damage morphology reveal subsurface feature in fused silica
Authors: Hu Guohang , Zhao Yuanan , Li Dawei , Xiao Qiling , Shao Jianda , Fan Zhengxiu 
Published: March 2010

AbstractWe present a detailed study of the morphology of 355 nm (6 ns) laser‐induced damage in fused silica polished by CeO2 solution. We see two distinct damage morphologies: the gray haze and the crater. The gray haze, consisting of a high density of pin‐points, appears at the fluence higher than ∼10 J/cm2, and the crater forms at ∼≥ 22 J/cm2. The size and depth of the pin‐points are much smaller than the crater. The difference in the two morphologies is attributed to the property of the absorber and its surrounding material in the redeposition layer, which is different from those in the subsurface damage layer. The damage growth characteristics of the two morphologies are measured, and the size of crater increases under successive shots, but the size of the gray haze remains constant. The growth of the crater is attributed to the existence of crack around the absorber, which is observed by SEM imaging. On the basis of the above analysis, the schematic diagram of subsurface feature is discussed. Copyright © 2010 John Wiley & Sons, Ltd.
Investigation of anomalous physical properties of multilayer nanolaminate (TiAl)N/Cu coatings by electron spectroscopy techniques
Authors: Kovalev Anatoly , Wainstein Dmitry , Rashkovskiy Alexandr 
Published: March 2010

AbstractIn accordance with high‐resolution transmission electron microscopy (HRTEM), (Ti34Al66)N/Cu physical vapour deposition (PVD) composite coating had a nanolaminated structure with 20 nm (Ti34Al66)N and 2.0–5.0 nm fine grain recrystallized Cu layers. It was unexpectedly found that the coatings under investigation had a lower thermal conductivity coefficient of 25 to 450 °C compared to the TiAlN single layer coating. The physical basis of thermo‐barrier protective features of copper nanolayers was explained based on XPS and high‐resolution electron energy losses spectroscopy (HREELS) data. The temperature dependence of the phonons and conducting electron vibrations was investigated for Cu bulk, (TiAl)N upper layer, and the intermediate Cu one. In comparison with Cu bulk reference sample, the intermediate Cu layers of complex PVD coating were characterized by the following features: size‐dependent shift of Cu 2p3/2 binding energy, reduced plasmon losses and acoustic mode phonon vibrations amplitudes, and increased intensities of the optical mode vibrations. These features of phonon and plasmon oscillations in the crystal lattice of Cu nanolayers do not completely explain the anomalies of the thermal conductivity of the (TiAl)N/Cu PVD coating. The thermal barrier properties of Cu nanolayers can be primarily attributed to the mirror effect or reflecting of the heat flux from the surface by metal layer with high concentration of conducting electrons. Copyright © 2010 John Wiley & Sons, Ltd.