bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mitochondrial DNA mutation stimulates prostate cancer growth in bone stromal environment
Authors: Arnold Rebecca S. , Sun Carrie Q. , Richards Jendai C. , Grigoriev Galina , Coleman Ilsa M. , Nelson Peter S. , Hsieh Chia‐Ling , Lee Jae K. , Xu Zhiheng , Rogatko Andre , Osunkoya Adeboye O. , Zayzafoon Majd , Chung Leland , Petros John A. 
Published: October 2008

AbstractBACKGROUND AND OBJECTIVESMitochondrial DNA (mtDNA) mutations, inherited and somatically acquired, are common in clinical prostate cancer. We have developed model systems designed to study specific mtDNA mutations in controlled experiments. Because prostate cancer frequently metastasizes to bone we tested the hypothesis that mtDNA mutations enhance prostate cancer growth and survival in the bone microenvironment.METHODSThe pathogenic nucleotide position (np) 8993 mDNA mutation was introduced into PC3 prostate cancer cells by cybrid formation. Wild‐type and mutant cybrids were grown as nude mouse subcutaneous xenografts with or without bone stromal cell co‐inoculation. Cybrids were also grown in the intratibial space. Tumor growth was assayed by direct tumor measurement and luciferase chemiluminescence. Gene expression was assayed using cDNA microarrays confirmed by real time PCR, western blot analysis and immunohistochemistry.RESULTSCybrids with the 8,993 mtDNA mutation grew faster than wild‐type cybrids. Further growth acceleration was demonstrated in the bone microenvironment. A 37 gene molecular signature characterized the growth advantage conferred by the mtDNA mutation and bone microenvironment. Two genes of known importance in clinical prostate cancer, FGF1 and FAK, were found to be substantially upregulated only when both mtDNA mutation and bone stromal cell were present.CONCLUSIONSThe ATP6 np 8,993 mtDNA mutation confers a growth advantage to human prostate cancer that is most fully manifest in the bone microenvironment. The identification of specific molecular alterations associated with mtDNA mutation and growth in bone may allow new understanding of prostate cancer bone metastasis. Prostate 69: 1–11, 2009. © 2008 Wiley–Liss, Inc.
Transition zone and anterior stromal prostate cancers: Zone of origin and intraprostatic patterns of spread at histopathology
Authors: Bouyé Sébastien , Potiron Eric , Puech Philippe , Leroy Xavier , Lemaitre Laurent , Villers Arnauld 
Published: October 2008

AbstractBACKGROUNDTo describe the precise location of transition zone (TZ) and anterior fibromuscular stroma (AFMS) prostate cancers (TZ/AFMS) within histological zones at various stages of development and to demonstrate their pattern of intraprostatic spread from their site of origin.METHODSAnterior TZ/AFMS cancers excluding the anterolateral part of peripheral zone, were identified from radical prostatectomy specimens. Morphometric histopathological study included largest surface area, volume and spatial distribution.RESULTSOut of 91 TZ/AFMS cancers, 79 were <4 cm3 and 69 <2 cm3. Fifty percent and 70% of cancers <4 cm3 were located in the anterior third and inferior half of TZ and/or AFMS, respectively. Cancers <2 cm3 could be classified into three types according to their location related to histologic zone boundaries: TZ type 1 (40%) for cancers confined to one TZ lobe; TZ type 2 (35%) for cancers most represented in one TZ lobe but crossing its anterior boundary; type AFMS (25%) for cancers confined to AFMS. These results form the rationale for the hypothesis that AFMS cancers originate from anterior and medial TZ and due to benign prostatic hypertrophy they become excluded from TZ, anteriorly into AFMS. TZ anterior limit would then act as a barrier to their posterior extension.CONCLUSIONSTZ/AFMS cancers contours and locations are predictable and conform to histological zones boundaries. Knowledge of these cancer origin and pattern of spread in TZ and AFMS are of importance for imaging diagnosis, guidance for biopsy and focal therapy. Prostate 69: 105–113, 2009. © 2008 Wiley–Liss, Inc.
Poisson ratio under compressive and tensile strain; effect on the mechanical response of the Cu46Zr54 metallic glass
Authors: Tayebi L. , Lekka Ch. E. , Evangelakis G. A. 
Published: October 2008

AbstractWe present Molecular Dynamics (MD) results demonstrating the effect of the Poisson ratio (PR) changes, occurring upon compressive and tensile deformation, on the mechanical response of Cu46Zr54 metallic glass (MG). We found that the PR value increases under strain, the effect being more pronounced after yielding. These changes are related to microstructural modifications occurring at subnano scale and to the plasticity of the material. In addition, we found that the effect depends on the imposed strain rate, yielding lower plastic region and fracture strain at high deformation rates. These findings indicate that microstructure, intrinsic properties and mechanical response of MGs are closely related and can be used for the design of MGs exhibiting enhanced plasticity. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Detection of CO and NO using low power metal oxide sensors
Authors: Triantafyllopoulou R. , Tsamis C. 
Published: October 2008

AbstractIn this work we present the fabrication and characterization of low power SnO2 gas sensors based on Porous Silicon micro‐hotplates for the detection of toxic gases, like CO and NO. The response of the SnO2 gas sensors was measured for various gas concentrations (100‐500 ppm). Analysis was performed in isothermal operation mode, by keeping constant the micro‐hotplate temperature and in pulsed temperature mode, by applying voltage pulses to the heater. In both cases, the response of the sensors increased as the temperature and the concentration of the detecting gases increased. Comparison between the two different operation modes, shows that the sensors exhibit higher sensitivity in pulsed temperature mode. In addition, with this technique, a significant reduction of power consumption can be achieved. Moreover, the sensors show significant selectivity in detecting NO, so discrimination between the two gases can be achieved. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cr/4H‐SiC Schottky contacts investigated by electrical and photoelectron spectroscopy techniques
Authors: Koliakoudakis C. , Dontas J. , Karakalos S. , Kayambaki M. , Ladas S. , Konstantinidis G. , Zekentes K. , Kennou S. 
Published: October 2008

AbstractCr/4H‐SiC Schottky contacts were investigated by standard electrical measurements and photoelectron spectroscopy. XPS (X‐ray Photoelectron Spectroscopy) measurements were performed during the in‐situ formation of the metal‐semiconductor interface formation as well as after several annealing steps of the Cr/4H‐SiC contact. A barrier height of 1.2 eV was determined from XPS measurements. The electrical measurements have showed the necessity of thermal annealing at 600 °C to obtain best performance (ΦB = 1.05 eV from C‐V measurements and 0.94 eV from I‐V measurements with ideality factor n = 1.08). (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
First‐principles study of the structural and electronic properties of the α modification of zinc diphosphide
Authors: Fan Chao‐Lei , Cheng Xin‐Lu , Zhang Hong 
Published: October 2008

AbstractFirst‐principles calculations are carried out to investigate the structural and electronic properties of the α modification of zinc diphosphide (α‐ZnP2). We use the conjugate gradient (CG) minimization method, in which both the local density approximation (LDA) and the generalized gradient approximation (GGA) as implemented in the SIESTA code are employed. The ground state properties such as the lattice parameters, bulk modulus, pressure derivative of the bulk modulus at zero pressure, bond lengths and bond angles are determined and compared with the available experimental data. The energy band structure and electron density of states (DOS) of α‐ZnP2 are also presented. By analyzing the electronic band structure, a band gap of 1.91 eV is obtained. Based on the study of properties of α‐ZnP2 at high pressure, it is found that the structural and electronic properties of α‐ZnP2 at high pressure are quite stable. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
First‐principles study on the boron antimony compound
Authors: Cui Shouxin , Feng Wenxia , Hu Haiquan , Feng Zhenbao 
Published: October 2008

AbstractThe structural, electronic, elastic and optical properties of the boron antimony (BSb) compound are investigated by first‐principles pseudopotential method. The calculations show the structural phase transition from the zincblende (ZB) to the rocksalt (RS) structures at the transition pressure of 56 GPa and with a volume reduction of 13%. The ground‐state, electronic and optical properties, i.e. the lattice constant, elastic constants, band structure, reflectivity and the refractive index, are calculated using the plane‐wave pseudopotential method within the density functional theory. We discuss our results and compare them with other theoretical studies. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Enhanced Raman scattering in grooved silicon matrix
Authors: Mamichev D. A. , Timoshenko V. Yu. , Zoteyev A. V. , Golovan L. A. , Krutkova E. Yu. , Laktyunkin A. V. , Kashkarov P. K. , Astrova E. V. , Perova T. S. 
Published: October 2008

AbstractMultiple enhancement of the Stokes Raman scattering in grooved silicon structures, which consist of sequences of voids (grooves) and crystalline Si walls, was observed under excitation with wavelength close to the Si wall width of ∼1 μm. The results obtained are interpreted as a manifestation of the partial light localization within the grooved structures, which increases the effective volume of the medium interacting with excitation light. Based on this effect, we conclude that grooved silicon structures can act as a matrix for increasing the Raman scattering efficiency of different substances embedded into the grooves. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Direct determination of intrinsic Inx Ga1–xP (x = 0.49) band‐gap deformation potentials by cathodoluminescence piezo‐spectroscopy
Authors: Porporati Alessandro Alan , Furukawa Naohide , Zhu Wenliang , Pezzotti Giuseppe 
Published: October 2008

AbstractWe determined to a degree of precision the complete set of three deformation potentials of zinc‐blende‐like (intrinsic) Inx Ga1–x P (x = 0.49) and found that their variation with chemical composition does not follow a linear rule‐of‐mixture between values of InP and GaP, as usually assumed in the published literature. Measurements were made according to a microscopic cathodoluminescence piezo‐spectroscopic (CL/ PS) procedure, previously calibrated for paradigm materials, which deformation potentials are known according to macroscopic calibration calibration procedures. The procedure followed in this study allowed us to obtain the desired deformation potential values directly on a thin film (i.e., without the need of a bulk sample), by exploiting the high spatial resolution of the electron probe. Microscopic strain fields were used, which were preliminary introduced by a pyramidal indentation print on the surface of the epitaxially grown film. The methodology enabled accurate deformation potential assessments in small material volumes for both tensile and compressive stress fields. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cluster perturbation study of 1D electron–hole Hubbard model
Authors: Asano Kenichi , Nishida Takuto , Ogawa Tetsuo 
Published: October 2008

AbstractWe studied the quarter‐filled electron–hole Hubbard model of one dimension using the cluster perturbation method. We found that the ground states of this system are always insulating as long as the electron–hole attractive interaction has a finite value. The calculated density of states for the electron and hole is significantly renormalized by the interaction, and show energy gaps at the Fermi energy. These gaps are induced by the excitonic mechanism at U > U ′ and by the biexcitonic one at U < U ′, where U (> 0) denotes the electron–electron and hole–hole repulsive interaction, and U ′(< 0) denotes the electron–hole attractive interaction. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Comparative study of excitonic structures and luminescence properties of Bi4Ge3O12 and Bi12GeO20
Authors: Itoh Minoru , Katagiri Tsuyoshi , Mitani Hiroyuki , Fujita Masami , Usuki Yoshiyuki 
Published: October 2008

AbstractMeasurements of reflection, emission‐excitation, luminescence decay kinetics, and X‐ray photoelectron of Bi4Ge3O12 and Bi12GeO20 crystals have been performed, in addition to relativistic molecular orbital calculations. Both materials consist of the same elements but form different crystal structures. Based on the obtained results, the excitonic reflection structures and luminescence properties of Bi4Ge3O12 and Bi12GeO20 are discussed in comparison with each other. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical evaluation of electron and hole g ‐factors in single quantum dots
Authors: Kaji R. , Yamada K. , Sasakura H. , Adachi S. 
Published: October 2008

AbstractPrecise optical evaluation of electron and hole g ‐factors in single InAlAs quantum dot was performed by using the optical pumping of nuclear magnetic field and its bistable behavior. The measurement is based on the fact that the induced nuclear field is effective only on electrons and can compensate the external magnetic field. The experimental results indicate that the effective electron g ‐factor can change in large magnitude including the sign in a controllable manner. Therefore, the method will be useful for the spin manipulation experiments such as photon‐spin qubit conversion. In addition, the in‐plane electron and hole g ‐factors were measured in Voigt geometry. This is the first report of individual g ‐factors of electron and hole in single InAlAs/AlGaAs quantum dots, which have been reported so far by only a few studies about the exciton g ‐factor. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Excitons in a perfect quasi‐1D organic quantum wire, an isolated polydiacetylene chain
Authors: Legrand Laurent , Choueiry Antoine Al , Holcman Jérémy , Enderlin Alexandre , Melet Romain , Barisien Thierry , Voliotis Valia , Grousson Roger , Schott Michel 
Published: October 2008

AbstractThe exciton in single luminescent polydiacetylene (PDA) chains dispersed in their single crystal monomer matrix is studied. As reported these quantum wires have the properties of a perfect quasi‐1D semiconducting system.The macroscopic spatial coherence of a single exciton state on a chain as a function of temperature is investigated using an interference experiment. The interference pattern contrast decreasing with increasing temperature is non zero up to 30 K.Experiments developed in order to observe the regime of formation of the stationary coherent exciton state are described. Within the time resolution of the experiment, it is concluded that the formation of this state is faster than ∼5 picoseconds which confirms the assumption of a transient regime.Finally the first steps of the manipulation of phase locked excitonic wave‐packets on a PDA wire are discussed. The experimental results measured in a weak exciton‐photon coupling regime are compared to simulations obtained through the Bloch optical equations in the framework of a three‐levels model. A direct estimate of the coherence time of the vibronic state photocreated in the present non resonant scheme is derived. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Negative linear thermal expansion of oblique‐angle (monoclinic and triclinic) crystals as a common case
Authors: Filatov Stanislav K. 
Published: October 2008

AbstractThe traditional principle of the mid‐twentieth century that ‘stronger chemical bonds imply a weaker thermal expansion' appeared to be valid for cubic crystals but failed to explain many cases of real high anisotropic thermal expansion of non‐cubic crystals. In particular, the discovery, a quarter of a century ago, of the frequent occurrence of negative linear thermal expansion in monoclinic and triclinic crystals was unexpected. For this reason, it is necessary to consider an additional principle of thermal expansion (symmetrical rearrangement of a crystal structure with temperature). According to both principles, the value of thermal expansion is dictated by the strength of chemical bonds, and the anisotropy of thermal expansion is determined mainly by the tendency of crystal symmetry to increase upon heating, etc. The last 25 years have proved to be a test and development period of thermal expansion theory. The principles mentioned above are considered in the light of their present‐day advancements. This allows us to achieve a better understanding of real thermal expansion. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Gas management through thick macroporous and mesoporousmacroporous membranes
Authors: Desplobain S. , Gautier G. , Gharbage N. , Ventura L. , Roy M. 
Published: October 2008

AbstractAmong all the potential applications of porous silicon, gas or liquid management through membranes is a key point in various micro‐system applications. In this paper, we compare the hydrogen flow through two different porous silicon structures. The first one is a 240 µm thick macroporous silicon membrane with pore diameters between 2 and 3 µm. The second one is a combination of a macroporous layer surmounted by a mesoporous one (average pore diameters of 10 nm). We present also a new method achieving the pore opening on the whole backside surface of the sample. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thick microporous silicon isolation layers for integrated RF inductors
Authors: Gautier G. , Leduc P. , Semai J. , Ventura L. 
Published: October 2008

AbstractIn this paper, we present processes to etch high thickness porous silicon layers for RF device applications. Indeed, on‐chip inductors realized on bulk silicon suffer from mediocre Q‐factor values mainly because of electrical losses into the substrate and capacitive coupling with the silicon appearing beyond 1 GHz. We present a detailed study of etching parameters such as the current density or the HF concentration in HF: H2O:acetic acid based electrolytes. In addition, we propose a prospective study of integrated copper inductor performances on porous silicon substrates in the range of 100 MHz to 10 GHz. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The effect of crystallization technology and gate insulator deposition method on the performance and reliability of polysilicon TFTs
Authors: Moschou Despina C. , Kontogiannopoulos Giannis P. , Kouvatsos Dimitrios N. , Voutsas Apostolos T. 
Published: October 2008

AbstractPolysilicon TFTs were fabricated using solid phase crystallization (SPC) and also two different excimer laser annealing techniques (ELA) for polysilicon crystallization. Moreover, we tried two different gate oxide deposition methods, using PECVD or TEOS LPCVD. Comparing the characteristics of the fabricated TFTs, we were able to probe the effects of the polysilicon crystallization techniques and the gate oxide deposition methods on TFT performance and reliability. This way, an optimization of the TFT fabrication procedure could be possible. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Investigation of top gate electrode options for high‐k gate dielectric MOS capacitors
Authors: Moschou D. C. , Verrelli E. , Kouvatsos D. N. , Normand P. , Tsoukalas D. , Speliotis A. , Bayiati P. , Niarchos D. 
Published: October 2008

AbstractCapacitors with a high‐k HfO2film as gate dielectric were fabricated, using three different variations for the top gate electrode. This way it was possible to acquire important information on which kind of gate material should be used in combination with HfO2as a gate insulator for optimum performance of possible low temperature applications, such as high‐k TFTs. The variations of gate electrode were e‐gun evaporated Al, sputtered W and CVD polysilicon followed by ion implantation and annealing. The capacitors were then characterized with capacitance‐voltage measurements and current‐voltage measurements. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Porous anodic alumina thin films on Si: interface characterization
Authors: Gianneta V. , Nassiopoulou A. G. , Krontiras C. A. , Georga S. N. 
Published: October 2008

AbstractPorous anodic alumina (PAA) thin films (thickness ∼ 50nm) were fabricated on Si by anodization of thin Al films under constant voltage of 20 V in sulphuric acid aqueous solution. The films exhibit cylindrical vertical pores of diameter ∼ 13–15 nm, arranged in hexagonal close packed structure. Electrochemical oxidation of the Si substrate through PAA, used as masking layer with openings in the pores, resulted in the formation of SiO2 dots at each pore tip. Two different kinds of films, namely with or without SiO2 dots at pore tips, were fabricated. In order to characterize the electrical quality of the interface of PAA thin films with Si, C‐V and G‐V measurements were performed on Metal‐Insulator‐Semiconductor (MIS) structures with Al metallization. The measurements were carried out in the voltage range +1.0 V to –3.0 V in steps of 0.05 V and in the frequency range 1 MHz to 100 Hz. The typical form of C‐V and G‐V curves of a MIS structure was obtained. In order to determine the interface trap density Dit, C‐f and G‐f measurements were performed as a function of the applied gate voltage in the depletion region. Dit was evaluated following the Conductance Method (E. H. Nicollian, and J. R. Brews, MOS Physics and Technology (J. Wiley & Sons, New York, 1982), p. 222 [1]). Both types of samples exhibit values of Dit in the order of 1011 eV–1cm–2. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Evaluation of a gas flow sensor implemented on organic substrate
Authors: Petropoulos A. , Kaltsas G. , Speliotis T. , Nassiopoulou A.G. 
Published: October 2008

AbstractIn this paper we present results of the evaluation of a thermal gas flow sensor device implemented on a printed circuit board (PCB) substrate by a combination of PCB and MEMs technologies. The device consists of 3 parallel Pt strip resistors in direct electrical contact to patterned copper tracks of the PCB. For planarization purposes, the Pt strips reside on a thick polymer layer (SU8). The central resistor plays the role of a heater and the two other resistors, situated symmetrically on both sides of the heater, are temperature dependent sensing elements. The three main advantages of this specific sensor are: the low thermal conductivity of the substrate materials (FR4 and SU8, with thermal conductivity ∼0.2 W(m·K)) which permits high sensitivity at low power, its robustness compared to suspended membrane sensors and its simple fabrication process. The sensor can operate in both hot wire and calorimetric modes. The sensor was mounted inside a 1.5m long tube with 25 mm2 cross sectional area and was evaluated in nitrogen flow up to 100 SLPM, which corresponds to Reynolds numbers up to 25.000. The sensor signal in both the calorimetric and the hot‐wire modes is a monotonous function of the flow rate. A very high sensitivity is obtained in the calorimetric mode at very low flow rates (<0.05SLPM), while the sensor signal in the hot‐wire mode appears to be a linear function of the flow rate throughout the entire measurement region. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)