bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth and Overgrowth of Ge/Si Quantum Dots: An Observation by Atomic Resolution HAADF-STEM Imaging
Authors: Zhi Dan , Midgley Paul A. , Dunin-Borkowski Rafal E. , Joyce Bruce A. , Pashley Don W. , Bleloch Andrew L. , Goodhew Peter J.
Published: April 2011

The formation of self-assembled quantum dots (QD) is of increasing interest for applications in optical, nanoelectronic, biological and quantum computing systems. From the perspective of fabrication technology, there are great advantages if the whole device can be made using a single Si substrate. Furthermore, GeSi is a model semiconductor system for fundamental studies of growth and material properties. In practice, as the MBE growth of heterostructures is inherently a non-equilibrium process, the formation of self-assembled nanostructures is both complex and sensitive to growth and overgrowth conditions. The morphology, structure and composition of QDs can all change during growth. It is therefore crucial to understand their structures at different stages of growth at the atomic scale. Here, the characterization of QD growth using high-resolution high angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) imaging is presented. Both the formation of uncapped QDs and the effect of the encapsulation are investigated, and the morphological and compositional evolution of the QDs and wetting layers are observed directly at the atomic scale for the first time. During encapsulation, the Ge content in the centres of the QD remains unchanged, despite significant intermixing, lateral spreading and a laterally inhomogeneous Ge distribution inside the Ge QD. The initial non-uniform wetting layer for the uncapped Ge QD becomes uniform after encapsulation, and a 3-monolayer-thick core with ∼ 60% Ge content is formed in the 2 nm-thick wetting layer with an average Ge content of ∼ 30%. The results were obtained by direct analysis of the Z-contrast STEM imaging without involving complex image simulations.
Electric Force Microscopy Of Individually Charged Silicon Nanoparticles
Authors: Melin Thierry , Diesinger Heinrich , Barbet Sophie , Deresmes Dominique , Baron Thierry , Stievenard Didier
Published: April 2011

We report on charge injection experiments performed on single silicon nanoparticles and their analysis by Electric Force Microscopy (EFM). An analytical model is presented, enabling a quantitative determination of the charge state of the semiconductor nanoparticles from EFM signals, for arbitrary tip and nanoparticle shapes.

Experimentally, we provide an analysis of the capacitive and charge interactions taking place in EFM of silicon nanoparticles deposited on conductive substrates. We demonstrate that the weak image interactions associated with charged nanoparticles -of dipole-dipole type- can be identified from a spectroscopic EFM analysis.

Finally, we address the issue of the charge injection mechanisms. From the hysteretic behaviour of the charge injection spectroscopy, we separate volume versus surface charge effects. We show that charges are mostly injected in the nanoparticle volume, with however some residual injection on the nanoparticle surface. Mechanisms of the charge saturation are discussed.
Subcritical CO2Assisted Polymer Surface Engineering at Low Temperatures
Authors: Yang Yong , Lee Ly James
Published: April 2011

Polymer-based Micro/Nano Electro Mechanical Systems (MEMS/NEMS) have attracted a great deal of interest from industries and academia. The common polymer processing methods involve either organic solvents or temperatures above the glass transition temperature (Tg), which is undesirable, particularly for biomedical applications. On the basis of different properties near polymer surfaces from those in the bulk, we introduce subcritical fluids (particularly carbon dioxide, CO2) into polymer surfaces to manipulate the polymer properties at the nanoscale so that we can achieve low temperature surface engineering. In this study, polymer surface dynamics under CO2were addressed using atomic force microscopy (AFM) and neutron reflectivity (NR). Monodispersed nanoparticles were deposited onto the smooth polymer surface and then embedded into the surface by annealing the sample at the pre-specified temperatures and CO2pressures. The embedding of nanoparticles in the proximity of the surface was measured using AFM, and thus the surfaceTgprofile could be determined. It was revealed that there is a rubbery layer of up to a hundred nanometers thick at the surface where theTgis lower than that in the bulk and CO2dramatically reduced the surfaceTg. NR studies also show that CO2can enhance chain mobility at the polymer surfaces below the polymer bulkTg. These results indicated that even low concentrated CO2greatly could enhance polymer chain mobility below theTgof the CO2–plasticized polymers. The thickness of the rubbery layer can be controlled by tuning either temperatures, or CO2pressures, or both, which makes it possible to engineer polymer surfaces at low temperatures. Guided by the CO2enhanced polymer surface dynamics, we developed a novel CO2bonding technique to succeed in low temperature bonding of polymers at the micro/nanoscales. This CO2bonding technique has been applied to seal polymeric nanofluidic biochips and construct well-defined three-dimensional (3D) biodegradable polymeric tissue scaffolds.
Real Time Measurement of Functional Groups Substitution on Fluorocarbon Surface by ATR FT-IR
Authors: Sato Yuki , Murahara Masataka
Published: April 2011

The photochemical reaction process steps in substituting the functional groups on the surface of fluorocarbon [FEP] by irradiating an Xe2 excimer lamp on water or formic acid and FEP placed on the attenuated total reflectance [ATR] prism, has been measured in real time. These steps include, water photo-dissociation, the defluorination of the FEP and the hydrophilic group substitution.

In case of formic acid, the absorption peaks of the -CHO in the region of 2940 cm−1 and the -COOH in the region of 1710 cm−1 decreased respectively by photo dissociation, but that of the -OH in the region of 3300cm−1 increased. The results indicated that the -CHO and -COOH have turned to -OH.

Furthermore, the contact angle with water was measured. When compared to the untreated sample, whose contact angle was 110 degrees, the contact angle of the sample treated with water and the Xe2 lamp irradiation for 25 minutes became 31 degrees, and that of the sample modified with formic acid and the lamp irradiated for 25 minutes further improved to 17 degrees. This implies that the hydrophilic groups were produced more in formic acid than in water.
Fabrication of Surface Nitridation Mask on GaAs Substrate for Nano-Lithography
Authors: Yamamoto Yo , Saito Kohji , Kondo Toshiyuki , Maruyama Takahiro , Naritsuka Shigeya
Published: April 2011

The surface nitridation of GaAs substrate under various conditions were performed and its surface morphology was studied by using atomic force microscope. The RMS roughness of the surfaces was closely related to formation of the particles which was formed by As evaporation and subsequent Ga migration, which was enhanced by higher substrate temperature.
Laser Fabrication and Characterization of Adhesive-Free Joints For Encapsulation of Biomedical Implant Devices
Authors: Newaz G. , Georgiev D. G. , Mian A. , Auner G. , Herfurth H. , Witte R.
Published: April 2011

Laser-fabricated joints of sub-millimeter widths between biocompatible, dissimilar materials have the potential for applications as encapsulation of miniature implant biomedical devices. In this work, we briefly describe the laser joining method of a very promising system, polyimide/titanium-coated borosilicate glass, and present and discuss results from characterization of such laser joints by means of mechanical failure (tensile) tests, optical microscopy, X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Our results suggest the formation of strong chemical bonds between Ti-containing species and certain polymeric functional groups. Mechanical tensile strength failure test showed that such joint experience only limited, disappearing with time degradation as a result of soaking in physiological solutions.
Fabrication of Novel Types of Colloidosome Microcapsules for Drug Delivery Applications
Authors: Paunov Vesselin N. , Noble Paul F. , Cayre Olivier J. , Alargova Rossitza G. , Velev Orlin D.
Published: April 2011

Novel colloidosome microcapsules with aqueous gel cores and shells of different polymeric colloid particles have been prepared and characterized. Our preparation technique involves templating water-in-oil emulsions stabilized by either polymeric microrods or polystyrene (PS) latex particles and subsequent gelling of the aqueous phase with a suitable hydrocolloid. The obtained colloidosome microcapsules were transferred in water after dissolving the oil phase in ethanol and multiple centrifugation/washing cycles with ethanol and water. The presence of an aqueous gel core was found to enhance the structural integrity and mechanical stability of the obtained colloidosomes. In the case of latex particles forming the colloidosome membrane, the effect of the oil type on the final structure of the colloidosome shell was also studied. It was shown that by using appropriate oil, the latex particles within the colloidosome shell can be partially or completely swollen which not only binds them together but also allows direct control over the membrane pore size and its permeability with respect to entrapped species. Such microcapsules can find various applications for development of novel drug and vaccine delivery vehicles, slow release of cosmetic and food supplements.
Electrodeposition Characteristics of Bismuth-Telluride Films
Authors: Prabhakar A. , Podlaha-Murphy E. J. , Murphy M. C. , Devireddy R. V.
Published: April 2011

This work is a part of an on-going research effort to develop an array of micro thermoelectric coolers (TECs) for highly localized control of temperature at the cellular level. Prefabrication experimentation and modeling were carried out to understand the behavior of the proposed device. Mathematical models were used to identify important device parameters and optimal device dimensions. Preliminary experiments have shown that it is feasible to produce the TECs through electrodeposition of bismuth and telluride on modules produced using a modified multistep LIGA (Lithographie, Galvanoformung and Abformung) technique. The development and characterization of the proposed TECs would enable the bioengineer highly localized control of temperature in a native or artificial tissue system. Thus enabling further usage of low temperatures in biological systems for both destructive (cryosurgical) and beneficial (cryopreservation) procedures.
Biodegradable Polymeric Nanoparticles for Tumor-Selective Tamoxifen Delivery: In Vitro and in Vivo Studies
Authors: Shenoy Dinesh B. , Chawla Jugminder S. , Amiji Mansoor M.
Published: April 2011

1. ABSTRACT: This study was performed to evaluate the in-vitro and in-vivo tumor-cellular uptake and biodistribution pattern of tamoxifen when administered intravenously as a simple solution and upon encapsulation into biodegradable, surface-modified poly(ε-caprolactone) (PCL) nanoparticles. PCL (MW ∼ 15, 000) nanoparticles were prepared by the solvent displacement method and characterized for particle size/charge and surface morphology (by scanning electron microscopy). We investigated the nanoparticle-surface modification potential of the hydrophilic stabilizer (Pluronic® F-68 and F-108) employed during the preparation by electron spectroscopy for chemical analysis (ESCA). Quantitative in-vitro cellular uptake of tritiated (3H) tamoxifen in solution form and as nanoparticulate formulation was assessed in MCF-7 breast cancer cells. In-vivo biodistribution studies for the same formulations were carried out in Nu/Nu mice bearing MDA-MB-231 human breast carcinoma xenograft. Spherical nanoparticles having positive zeta potential (∼25 mV) were obtained in the size range of 200-300 nm. Pluronics (both F-68 and F-108), the triblock copolymers of poly(ethylene oxide) (PEO) and poly(propylene oxide) induced surface hydrophilization of the nanoparticles via adsorption as evident by ESCA. Nanoparticulate formulations of tamoxifen achieved higher intracellular concentrations when exposed at therapeutic concentrations to tumor cells in-vitro compared to solutions. The in-vivo biodistribution studies carried out in nude mice bearing experimental breast tumor suggested increased tumor concentrations for the drug administered as nanoparticulate formulations besides longer retention times within tumor mass. This type of delivery system is expected to provide better therapeutic benefit by dual means: preferential concentration within the tumor mass via enhanced permeation and retention pathway, and; subsequent controlled release, thus maintaining the local drug concentration for longer periods of time to achieve maximal cell-kill.
Matrix Assisted Pulsed Laser Evaporation of Poly (D, L) Lactic Acid Films
Authors: Patz Timothy M. , Doraiswamy Anand , Narayan Roger , Menegazzo Nicola , Kranz Christine , Mizaikoff Boris , Modi Rohit , Chrisey Douglas B.
Published: April 2011

We have deposited poly (D, L lactic acid) (PDLLA) thin films using matrix assisted pulsed laser evaporation (MAPLE). FTIR spectroscopy revealed that the PDLLA had similar absorption bands to the dropcast material. X-ray photoelectron spectroscopy has shown that peaks corresponding to C-H, C-O and C=O represented 38.4, 30.1 and 31.4% of the C1s spectrum, respectively. XPS O1s analysis revealed that the O=C and O-C components make up 52 and 48 % of the O1s content. Atomic force microscopy revealed that MAPLE deposition provides smooth, continuous thin biomaterial films. These matrix assisted pulsed laser evaporation-deposited biomaterial thin films may serve to improve the implant/tissue interface.
New biological labels based on functionalized YVO4: Eu nanoparticles
Authors: Giaume D. , Buissette V , Lahlil K. , Gacoin T. , Boilot J.-P. , Casanova D. , Beaurepaire E. , Sauviat M.-P. , Mercuri A. , Alexandrou A.
Published: April 2011

Lanthanide-ion doped oxide (YVO4: Eu) nanoparticles were synthesized as aqueous colloids and functionalized by a bioactive silane shell to be used as fluorescent biological labels. Nanoparticles functionalized with guanidinium groups were able to act as artificial toxins which specifically target Na+ channels. They were individually detectable in live cardiac myocytes. Functionalized oxide nanoparticles appear as a new interesting tool, especially attractive for long-term single-molecule tracking due to their photo-stability and long luminescence lifetime.
Hydrothermal Synthesis of the Deep-UV NLO Material Sr2Be2B2O7
Authors: Kolis Joseph W. , McMillen Colin D. , Franco Taina
Published: April 2011

The synthesis of non-linear optical (NLO) materials that are transparent into the deep-UV (<200 nm) region is an important component in the development of advanced optical technology. Such materials are sought after for their potential applications in the fields of high resolution photolithography, micro-machining, and laser spectroscopy. Borates are one class of solid-state materials that have received consideration for these applications because of their favorable physical and optical properties. One such compound, Sr2Be2B2O7(SBBO) has been reported to be transparent below 200 nm, and exhibits a large second harmonic generation (SHG) coefficient. Significant difficulties in the flux growth of large, high quality crystals have prevented this material from further development. We have successfully grown large crystals of SBBO by a hydrothermal synthetic method for the first time, and have characterized their physical properties. The synthesis and structure of a new material encountered during the synthesis of SBBO, LiBeSr2B3O8, is also reported here.
Dramatically Enhanced Thermoelectric Properties of Ca3Co4Oy by Large Amount of RE Substitution
Authors: Sugiura Y. , Horii S. , Kumagai T. , Okamoto T. , Otzschi K. , Shimoyama J. , Kishio K.
Published: April 2011

We report the synthesis and thermoelectric properties of [(Ca1-xREx)2CoO3-δ]0.62CoO2 compounds (RE: rare earth element, RE = Y, Sm, Eu, Tb, Dy, Ho and Lu). From optimization of synthesis conditions, all the chosen RE in this study were able to be substituted for the Ca sites in the block layers up to x = 0.25. In the case of RE = Tb, at 1150 K, only κ was systematically decreased with x, while both Seebeck coefficient (S) and resistivity (ρ) were almost constant for the charge of x. Consequently, the dimensionless figure of merit (ZT) was increased with x and reached 0.2 at 1150 K for x = 0.25. Moreover, interestingly, it was found that S and ρ at 300 K were enhanced with ionic radius of the doped trivalent RE ions in spite of the doping of equivalent RE ions. This is probably because local structures of oxygen sites around Co ion in the CoO2 layers largely depend on kinds of the doped RE.
Study Of Electrical, Chemical And Structural Characteristics Of Superconductor Thin Film Obtained By Polymeric Precursors Method
Authors: Carvalho C.L. , Peruzzi R.O. , Junior D.R.
Published: April 2011

Superconductor films of the BSCCO system have been grown by dip coating technique with good success. The chemical method allows us to grow high temperature superconductor thin films to get better control of stoichiometry, large areas and is cheaper than other methods. There is a great technological interest in growth oriented superconductor films due anisotropic characteristics of superconductor materials of high critical temperature, specifically the cuprates, as we know that the orientation may increase the electrical transport properties. Based on this, the polymeric precursor method has been used to obtain thin films of the BSCCO system. In this work we have applied that method together with the deposition technique known as dip coating to obtain Bi-based superconductor thin films, specifically, Bi1.6Pb0.4Sr2.0Ca2.0Cu3.0Ox+δ, also known as 2223 phase with a critical temperature around 110 K. The films with multilayers have been grown on crystalline substrates of LaAlO3 and orientated (100) after being heat treated around 790°C - 820°C in lapse time of 1 hour in a controlled atmosphere. XRD measurements have shown the presence of a crystalline phase 2212 with a critical temperature around 85 K with (001) orientation, as well as a small fraction of 2223 phase. SEM has shown a low uniformity and some cracks that maybe related to the applied heat treatment. WDS has also been used to study the films composition. Different heat treatments have been used with the aim to increase the percentage of 2223 phase. Measurements of resistivity confirmed the presence of at least two crystalline phases, 2212 and 2223, with Tc around 85 K and 110 K, respectively.
Magnetic Properties of a New One-Dimensional Vanadium Oxide with the Hollandite Structure.
Authors: Chernova Natasha A. , Katana Ngala J. , Zavalij Peter Y. , Stanley Whittingham M.
Published: April 2011

The magnetic properties of the first hollandite-type vanadium oxide containing anions in the 2×2 channels, V7.22O8(OH)8(Cl)0.77(H3O)2.34, are studied using static (DC) and dynamic (AC) magnetic susceptibilities. From the high-temperature Curie-Weiss behavior the effective magnetic moment is found consistent with the 3+ vanadium oxidation state; the negative Curie-Weiss temperature Θ ≈ -500 K indicates strong antiferromagnetic exchange. The DC magnetic susceptibility shows a rapid increase and the AC susceptibility shows a maximum at about 20 K, indicating magnetic phase transition. The field-cooled and zero-field-cooled susceptibilities diverge below the transition temperature. The real and imaginary components of the AC susceptibility show frequency dependence and shift of maximum toward lower temperatures with decreasing frequency. Analysis of the frequency dependences reveals at least three different relaxation processes existing around and below the transition temperature. The temperature dependences of their relaxation times were obtained using Cole-Cole analysis. We show that the magnetic behavior observed is well explained by the random-field Ising model, with randomness brought on by vacancies in vanadium sites.
Formation Mechanisms of Perovskite Pb(Ni1/3Nb2/3)O3 in Reaction-sintering Process
Authors: Liou Yi-Cheng , Huang Yi-Chen , Wu Chi-Ting
Published: April 2011

Formation mechanisms of perovskite Pb(Ni1/3Nb2/3)O3 (PNN) in the reaction-sintering process were investigated. Only the reflections of raw materials were detected at 400°C. For pellets heated to 500°C, pyrochlore phase Pb2Nb2O7 (P2N2) are found. Cubic Pb3Nb4O13 (P3N4) pyrochlore phase formed and became the main phase in pellets heated to 600°C. After being heated to 800°C, Pb3Nb2O8 (P3N2) pyrochlore phase formed in the pellets. As the pellets were heated to 900°C, the peak of NiNb2O6 columbite phase appeared. In pellets heated to 950°C, the weak peaks of PNN perovskite phase appeared. This means the perovskite phase formed at a temperature between 900°C and 950°C. As the pellets were heated to 1000°C, a large amount of PNN was formed and became dominant. The PbO, NiNb2O6 and Pb3Nb2O8 phases disappeared. The P3N4 content increased with temperature in pellets heated to 1050–1200°C. For pellets heated to 1250°C, the P3N4 content decreased significantly.
Femtosecond laser interactions with Co/Al multilayer films
Authors: Picard Yoosuf N. , Adams David P. , Yalisove Steven M.
Published: April 2011

Reactive multilayer films of Co and Al were irradiated using femtosecond and nanosecond pulse-length lasers. While no ignition of a self-propagation reaction occurred during the laser machining studies, we observe considerable differences in the morphology and extent of damage induced by femtosecond and nanosecond lasers. Using scanning electron microscopy, we show that single metal layers can be removed at the micron scale with negligible damage to the underlying layers using femtosecond pulse-length lasers.
Laser ablation-based nanofabrication in aqueous solutions
Authors: Kabashin Andrei V. , Meunier Michel
Published: April 2011

An overview of research results related to the femtosecond laser ablation-based method for nanofabri-cation in aqueous solutions is presented. The method makes possible the production of stable biofunctionalized gold nanoparticle colloids with extremely small size (down to 2–2.5 nm) and size dispersion (down to 1–1.5 nm). The colloids are of importance for biosensing applications.
Liquid Crystal Influenced Self-assembly in Mesogenic Polymer and Liquid Crystal Blends
Authors: Li Lanfang , Catanescu Carmen Otilia , Chien Liang-Chy
Published: April 2011

In this work, we found that by performing photo-polymerization of the mesogenic monomer RM257 in liquid crystals, well organized polymer walls were formed through out the cell by self-assembly of the polymer within the anisotropic host – the liquid crystal. The polymerization conditions, which were parameterized as UV intensity, photo-reactivity (characterized by photo initiator concentration), curing temperature, monomer concentration and mesophase of the liquid crystal host, were systematically varied. Different liquid crystal host also raised some difference in polymer network. We believe this kind of morphology comes from spinodal decomposition and the anisotropic elastic property of the liquid crystal host. It is found that for RM257 and low molecular weight nematic liquid crystals a monomer concentration of 5% is sufficient to use liquid crystal hosts to work as templates for well structured polymer walls.
Target Morphologies in Polymer Blends
Authors: Clarke Nigel , Henderson Ian
Published: April 2011

We model a novel process for obtaining controlled morphologies in polymer blends. Particles of one type of polymer are allowed to dissolve in a matrix of a dissimilar polymer. Prior to complete dissolution the blend is quenched into the two phase region, such that phase separation takes place. The combination of the incomplete dissolution and the wavelength selection process associated with phase separation results in particles that during the ‘intermediate’ stages have a core that is significantly rich in the matrix material. The concept is extended to consider the effect of phase separation on an inhomogeneous surface chemically patterned with regions which are more attractive to one component of the blend.
Multi-Block Copolymers in Selective Solvent: A Brownian Dynamics Simulation
Authors: Liu Yongsheng , Nie Huifen , Bansil Rama , Zhang Zhenli , Glotzer Sharon
Published: April 2011

We performed Brownian Dynamics simulations of multiblock copolymers of A and B polymers in a solvent selective for the A block at a volume fraction of 20%. Tri-, penta- and heptabocks were simulated. Fourier transformation reveals micellar clusters arranged in a BCC lattice, in agreement with scattering experiments. The clusters were analyzed using a percolation approach and we observed larger clusters when the outermost block was in the poor solvent condition. The ratio of number of loops to bridges decreases as the number of blocks in the copolymer increases, as does the polydispersity. Increased penalty of looping as the number of blocks increases leads to a larger number of smaller clusters with more bridges.
Association Between Chronic Periodontitis and Vasculogenic Erectile Dysfunction
Authors: Sharma Anuj , Pradeep A.R. , Raju P. Arjun
Published: April 2011

Background: Erectile dysfunction (ED) and chronic periodontitis (CP) share common risk factors. There is only one report on the association between ED and CP. Thus, the aim of this study is to find the association between vasculogenic ED and CP.

Methods: A total of 70 patients (mean age: 35.3 ± 3.64 years) clinically diagnosed with ED were included in the study. They were given the Sexual Health Inventory for Men Questionnaire and subjected to colored penile Doppler ultrasound. Periodontal parameters of probing depth and periodontal attachment level were recorded. Five patients with ED and CP were selected randomly for cardiac color Doppler to assess the integrity.

Results: Among the selected vasculogenic patients with ED, mild‐to‐moderate vasculogenic ED showed the highest prevalence, whereas prevalence for CP among all vasculogenic patients with ED was highest among severe ED (81.8%). Association of CP and vasculogenic ED was found to be correlated positively, but it showed no statistical significance. Two of five patients were found to have vascular insufficiency.

Conclusions: It can be hypothesized that an association exists between vasculogenic ED and CP in young males. However, a large‐scale study with confounder analysis and a longitudinal follow‐up is warranted.
Pollutant concentrations from deciduous wood fuelled heat station
Authors: Juszczak Marek
Published: April 2011

Pollutant concentrations from deciduous wood fuelled heat station

CO, NO, NO2 and dust concentrations from combustion of deciduous wood (birch, beech, lime-tree) logs and pellets in two heating boilers (15 and 25 KW), situated in a heat station were investigated. Time dependences of pollutant concentrations as well as the impact of temperature in the combustion chamber and oxygen concentration on pollutant concentrations were presented. Pollutant emission indices have been estimated.
Epigallocatechin Gallate Inhibits the HIV Reverse Transcription Step
Authors: Li Shenwei , Hattori Toshio , Kodama Eiichi N
Published: April 2011

Background:

Epigallocatechin gallate (EGCG), the most abundant catechin in green tea, has been reported to inhibit HIV-1 replication prior to its integration into host DNA via various proposed mechanisms; however, the specific main target(s) of EGCG remain unclear. In this study, we investigated a number of these proposed detailed mechanism(s) using a cell-based model.

Methods:

Multinuclear activation of galactosidase indicator assays were used for all experiments, including examination of the time of addition and the synergisms with a nucleoside reverse transcriptase inhibitor, 3′-azido-3′-deoxythymidine (AZT).

Results:

The experiments revealed that EGCG suppressed both HIV-1IIIB and HIV-2EHO infection in HeLa-CD4-LTR-β-gal cells, with relatively low 50% effective concentrations of 1.6 and 2.0 μM, respectively. The inhibitory profile of EGCG generated using a time-of-addition assay was identical to that of a non-nucleoside reverse transcriptase inhibitor (NNRTI), MKC-442. Furthermore, synergistic inhibition was observed in EGCG with AZT.

Conclusions:

Based on our findings, EGCG appears to act mainly as an allosteric reverse transcriptase inhibitor with mechanisms different from those of currently approved NNRTIs that directly interact with the NNRTI binding pocket. Thus, EGCG is a good candidate for use as an additional or supportive anti-HIV agent derived from natural plants.
L'ethno-folkloristique irlandaise
Authors: Ó Crualaoich Gearóid
Published: April 2011

Résumé Le développement de la folkloristique et de l’ethnologie en Irlande peut se lire à travers l’histoire de la discipline, telle qu’elle se reflète dans la carrière de ses chercheurs. La biographie de l’auteur, sa formation en tant qu’enseignant-chercheur notamment, est ainsi exposée pour montrer l’émergence d’un regard scientifique à partir d’un contexte d’oralité vernaculaire. Un programme de recherche portant sur un quartier de la ville de Cork, le Northside, permet d’illustrer l’application de ce regard à la pratique de l’ethnologie urbaine en Irlande.
Le savoir, enjeu d'une lutte de pouvoir entre l'agriculteur et le scientifique
Authors: Crowley Ethel
Published: April 2011

Résumé Cet article analyse l’application en Irlande du reps , le Rural Environment Protection Scheme. Il s’intéresse à des approches concurrentes du savoir, ainsi qu’à la prédominance de la science, manifeste dans le débat sur la politique agro-environnementale. La science est en effet utilisée comme une stratégie d’officialisation qui permet de justifier l’intervention de l’État dans l’agriculture. Toute objection provenant des agriculteurs est ainsi jugée dépassée et par conséquent illégitime. Les politiques culturelles se décidant en fonction des représentations de l’environnement, les fermiers et les conseillers agricoles se livrent une lutte symbolique ou idéologique.
Des droits civils au carnaval : anthropologie de l'espace public à Belfast
Authors: Bryan Dominic
Published: April 2011

Résumé Cet article traite de la maîtrise et de l’utilisation de l’espace public, un trait caractéristique de la politique et de l’identité en Irlande du Nord, en milieu urbain notamment. L’auteur montre que l’utilisation de l’espace public dans le centre de Belfast a changé et semble témoigner d’une évolution des identités. Il conclut par une double interrogation. Une nouvelle identité civique, englobant les clivages politiques et ethniques, se développe-t-elle et, si oui, surmontera-t-elle la ségrégation résidentielle qui progresse dans Belfast et sa zone urbaine ?
Le cas des Bretons de Paris
Authors: Madec Annick
Published: April 2011

Résumé Depuis la fin du xix e  siècle, les migrants bretons à Paris sont l’objet d’écrits dans la presse et les discours politiques. Les intérêts des uns se superposent souvent à ceux des autres car ceux qui sont communément désignés comme les Bretons de Paris sont convoqués par une presse généralement engagée. À la moitié du xx e  siècle, les sciences sociales et la littérature nous donnent à voir des réalités plus complexes. Cet article se propose de montrer que l’ensemble de ces constructions de la catégorie « migrants bretons à Paris » témoigne de façon exemplaire du fait que l’ethnicisation des rapports sociaux aboutit à gommer la pluralité et l’hétérogénéité des processus migratoires.
La décharge
Authors: Morel Geneviève
Published: April 2011

Résumé « C’était plus fort que moi, il fallait que je vole … C’était une drogue. C’était pas pour la drogue. C’était une drogue. » L’entretien avec Serge met au jour l’enchaînement fatal qui l’a entraîné à voler dès l’enfance, pour commémorer répétitivement un deuil précoce. À côté des jouissances procurées par le vol, qui réalise, comme le dit Jean Genet, « un rassemblement de soi » ritualisé, puis par la drogue, ni le sexe ni l’amour ne font vraiment le poids …
Die harte Nummer, ou « le chiffre dur ». Aspects d'une cure avec un analysant toxicomane
Authors: Meyer zum Wischen Michael
Published: April 2011

Résumé Pendant la cure, un toxicomane affirme qu’il a toujours recherché dans sa vie « le chiffre dur » (« die harte Nummer », littéralement traduit par le numéro dur, le numéro difficile). On montrera comment cet homme, psychotique, qui souffre de troubles de la pulsion orale, s’applique à suppléer à la forclusion du phallus : il invente un sinthome, « le chiffre dur » de sa parole et de son art.
Malnutrition et action humanitaire. Perspectives historiques et enjeux contemporains
Authors: Ryfman Philippe
Published: April 2011

Résumé Née au milieu du xix e siècle, l’action humanitaire entre en interaction avec les questions de nutrition – à partir, surtout, de la malnutrition infantile et de sa prise en charge – depuis les années 1980. S’appuyant sur tout un apparat conceptuel et technique mis en place par des agences onusiennes (l’ unicef particulièrement), des ong humanitaires et le cicr , la malnutrition devient un champ d’action majeur. Cependant, dans un monde où près d’un milliard de personnes demeurent aujourd’hui victimes de sous-nutrition, un certain nombre de questions se posent désormais sous un angle nouveau, comme l’ont montré – par exemple – les divergences d’analyses pour qualifier la situation au Niger en 2005 ou le départ forcé de msf - f de ce pays à l’automne 2008 – avant son retour en 2010.
Politique de la bouche
Authors: Maier Corinne
Published: April 2011

Résumé Le pouvoir souhaite réguler la pulsion orale pour des motifs politiques. La bouche serait-elle la poursuite de la politique par d’autres moyens ? On étudiera tout particulièrement le cas de l’Allemagne.
Présentation de l'ouvrage de François Perrier. L'alcool au singulier, L'eau de feu et la libido
Authors: Ego Sylvette
Published: April 2011

Résumé François Perrier, psychiatre et psychanalyste (1922-1990), écrivit un ouvrage où il décrit et tente d’analyser son expérience de l’alcoolisme. Le titre, ainsi que le contenu, témoignent d’une réalité que Ferenczi, déjà, avait mise en évidence : l’alcool se vit toujours « au singulier ». Il est une conséquence, non une cause, d’une souffrance psychique ; il contribue même à la rendre supportable, jusqu’à ce que le médicament devienne le poison. Cet acquis de la psychanalyse mérite d’être réaffirmé.
Le rien ironique de la psychanalyse
Authors: Teixeira Antonio
Published: April 2011

Résumé L’auteur oppose le rien ironique de la clinique psychanalytique à la positivité du sens normatif de la prise en charge psychiatrique. Ce faisant, il montre que la psychanalyse, au lieu de prescrire le sens du discours thérapeutique, se vaut de la phrase-prétexte, vide de sens, sur laquelle la parole de son patient peut s’embrayer. Il est plutôt question, pour l’analyste, de s’offrir au sujet sous les espèces d’une sollicitude qui ne met pas son propre souci à la place du souci de celui dont il s’occupe.
Oxidative Stress in Dog with Heart Failure: The Role of Dietary Fatty Acids and Antioxidants
Authors: Sagols Emmanuelle , Priymenko Nathalie
Published: April 2011

In dogs with heart failure, cell oxygenation and cellular metabolism do not work properly, leading to the production of a large amount of free radicals. In the organism, these free radicals are responsible of major cellular damages: this is oxidative stress. However, a suitable food intake plays an important role in limiting this phenomenon: on the one hand, the presence of essential fatty acids in the composition of membranes decreases sensitivity of cells to free radicals and constitutes a first protection against the oxidative stress; on the other hand, coenzyme Q10, vitamin E, and polyphenols are antioxidant molecules which can help cells to neutralize these free radicals.
On a Local Theory of Asymptotic Integration for Nonlinear Differential Equations
Authors: Agarwal Ravi P. , Mustafa Octavian G.
Published: April 2011

We improve several recent results in the asymptotic integration theory of nonlinear ordinary differential equations via a variant of the method devised by J. K. Hale and N. Onuchic The results are used for investigating the existence of positive solutions to certain reaction-diffusion equations.
Univalently Induced, Closed Range, Composition Operators on the Bloch-type Spaces
Authors: Zorboska Nina
Published: April 2011

While there is a large variety of univalently induced closed range composition operators on the Bloch space, we show that the only univalently induced, closed range, composition operators on the Bloch-type spaces Bα with α ≠ 1 are the ones induced by a disc automorphism.
Odontogenic Myxoma: A Case Report and Retrospective Analysis of Five Cases
Authors: Kale Tejraj Pundalik , Kotrashetti SM , Janardhan Sruthi
Published: April 2011

Odontogenic myxoma is a rare, locally aggressive, benign tumor of the jaws representing less than 0.5% of all bone tumors and only 3 to 6% of odontogenic tumors. This article reviews five cases of the same treated in the Department of Oral and Maxillofacial Surgery, KLE's VK Institute of Dental Sciences between 1993 and 2010. One case of left maxillary sinus odontogenic myxoma in a 30-year-old female patient was of aggressive nature and has been described in detail in this report.
An Anion‐Conjugated Polyelectrolyte Designed for the Selective and Sensitive Detection of Silver(I)
Authors: Hu Yuqin , Xiao Yi , Huang Hongmei , Yin Dulin , Xiao Xiaoming , Tan Weihong
Published: April 2011

A novel conjugated polyelectrolyte P1, having a meta‐substituted monopyridyl in the backbone, is designed and synthesized for Ag+ detection in aqueous solution. As a chemosensor, P1 shows high sensitivity, low detection limit, and excellent selectivity for Ag+ over other metal ions. The sensing mechanism is based on the specific interaction between Ag+ and the pyridyl group of P1. The aggregated state of the polymer in water can amplify its quenching efficiency.
Option hedging by an influential informed investor
Authors: Eyraud‐Loisel Anne
Published: April 2011

This work extends the study of hedging problems in markets with asymmetrical information: an agent is supposed to possess an additional information on market prices, unknown to the common investor.

The financial hedging problem for the influential and informed trader is modeled by a forward–backward stochastic differential equation, to be solved under an initial enlargement of the Brownian filtration. An existence and uniqueness theorem is proved under standard assumptions. The financial interpretation is derived, in terms of investment strategy for the informed and influential agent, as well as the conclusions concerning the general influenced market, in terms of completeness of the market. An example of such influenced and informed model is provided. Copyright © 2011 John Wiley & Sons, Ltd.
Anion‐Templated Assembly of Half‐Sandwich Rhodium‐Based Multinuclear Metallamacrocycles
Authors: Wang Guo‐Liang , Lin Yue‐Jian , Jin Guo‐Xin
Published: April 2011

A series of half‐sandwich rhodium‐based metallamacrocycles with tetra‐ and hexanuclearities have been synthesized. They are assembled by linking the deprotonated 2,4‐diacetyl‐5‐hydroxy‐5‐methyl‐3‐(3‐pyridinyl)cyclohexanone (HL) ligand in the presence of counteranions. When the counteranion was the tetrahedral BF4− ion, tetranuclear metallamacrocycle [(Cp*RhL)4][BF4]4 (1 d) was formed. However, the larger OTf−, PF6−, and SbF6− counterions favored the formation of hexanuclear metallamacrocycles [(Cp*RhL)6⊃2OTf][OTf]4 (1 a), [(Cp*RhL)6⊃2PF6][PF6]4 (1 b), and [(Cp*RhL)6⊃2SbF6][SbF6]4⋅6CH3CN (1 c) when the reactions were performed under the same conditions. Single‐crystal X‐ray analysis indicated that, in the solid state, two counteranions were encapsulated in each belt‐like host molecule of hexanuclear metallamacrocycles 1 a, b, and c. Based on the results of 1H NMR analysis in methanol, the nuclearities of 1 a–c and the two encapsulated anions in each molecular cavity were maintained in solution. In addition, tetranuclear metallamacrocycle 1 d was converted into the hexanuclear metallamacrocycles 1 a′, b, and c after addition of the appropriate anion as its [NBu4]+ salt. The compound 1 a′ was characterized by single‐crystal X‐ray diffraction to have the formula [(Cp*RhL)6⊃2OTf][BF4]4⋅2MeOH⋅2H2O. From the interconversion of the hexanuclear metallamacrocycles, we have concluded that the hexanuclear belt‐like host in 1 a–c has an clear selectivity for larger anions, in the sequence SbF6−≈PF6−>OTf−>BF4−>Cl−.
Assessment of clinical and analytical performance characteristics of an HPV genotyping test
Authors: Schutzbank Ted E. , Ginocchio Christine C.
Published: April 2011

Human papillomavirus (HPV), the known cause of cervical cancer, is found in essentially all cervical cancer specimens. Infection with high‐risk HPV genotypes carries the greatest risk of viral persistence and the potential to develop precancerous lesions or cervical cancer. Identifying women infected with HPV 16 and/or 18, the two genotypes most commonly found in cervical cancer, helps further stratify women for either immediate referral to colposcopy or repeat cytological and HPV DNA testing in 12 months. Genotyping additional, less carcinogenic HPV types may be of limited clinical utility. Detection of multiple individual genotypes may capture a greater percentage of those with the potential to develop cervical disease. However, the advantage of individual detection must be weighed against the potential error of multiple measurements. In order for genotyping tests to have clinical benefit in patient management, the Centers of Medicare and Medicaid Services Divisions of Laboratory Services have set forth a rigorous clinical validation procedure. This procedure addresses the quality process, characteristics and specifications of the assay, comparison of the test/device to existing tests/devices, technical aspects, and other assurances that guarantee the test/device will meet all performance requirements of the US Food and Drug Administration (FDA). Currently, only the Cervista® HPV 16/18 genotyping test is approved by the FDA and recommended for clinical use in published guidelines. This manuscript reviews the current best practices for the development and use of HPV genotyping tests. Diagn. Cytopathol. 2011; © 2011 Wiley‐Liss, Inc.
Metastatic chromophobe renal cell carcinoma in pleural fluid cytology: Review of literature and report of a case
Authors: Davion Simone , Rohan Stephen , Nayar Ritu , Kulesza Peter
Published: April 2011

The majority of chromophobe renal cell carcinomas (CHRCC) are not aggressive, however, a subset are. The potential for metastasis makes recognition of CHRCC cells in cytologic preparations important for patient surveillance, management, and treatment. We report the detection of an aggressive form of CHRCC in pleural fluid cytology with histopathologic confirmation on subsequent pleural biopsy. Sarcomatoid portions of the original CHRCC, and the pleural metastasis, demonstrated loss of diffuse membranous staining with C‐KIT. Diagn. Cytopathol. 2012. © 2011 Wiley Periodicals, Inc.
Simultaneous Detection of Trace Cadmium(II) and Lead(II) Using an Unmodified Edge Plane Pyrolytic Graphite Electrode
Authors: Lu Min , Toghill Kathryn E. , Compton Richard G.
Published: April 2011

We report the sensitive simultaneous detection of cadmium(II) and lead(II) using an unmodified edge plane pyrolytic graphite (EPPG) electrode via linear sweep anodic stripping voltammetry (LSASV). Simultaneous additions of the heavy metals gave two well separated stripping peaks observed over two linear ranges, 20 to 200 µg L−1and 2 to 20 µg L−1. These gave detection limits of 0.3 µg L−1and 0.2 µg L−1for cadmium(II) and lead(II), respectively. The use of unmodified EPPG electrodes shows comparable performance to bismuth and mercury modified electrodes, and offers a simple and effective alternative to modified systems.
Preparation of a Preplated Bismuth Film on Pt Electrode and its Application for Determination of Trace Aluminum(III) by Adsorptive Stripping Voltammetry
Authors: Wang Hongmei , Yu Zhanglong , Wang Zhiliang , Hao Haijun , Chen Yongmei , Wan Pingyu
Published: April 2011

Adsorptive stripping voltammetry (AdSV) was successfully explored for the determination of aluminum(III) in sodium carbonate solution (1 M) on a preplated bismuth film electrode (BiFE). Microscopic investigation displays that the morphology of the preplated bismuth film on Pt electrode relates to the plating conditions. The resulted perfect dendritic polycrystalline BiFE demonstrates better performance than the flake single crystal BiFE in AdSV determination of Al(III) in the presence of Eriochrome blue black R (EBBR). Under the selected conditions, the limit of detection(3σ) for Al(III) on flake and dendrite BiFE are 1.02×10−8 M and 5.6×10−10 M, respectively, and the current variation ratio of the coexistent ions(CaII, VV, SiIV, MgII, FeII and FeIII) is less than ±0.700 % in all cases.
The essential oil of Abies sibirica (Pinaceae) reduces arousal levels after visual display terminal work
Authors: Matsubara Eri , Fukagawa Mio , Okamoto Tsuyoshi , Ohnuki Koichiro , Shimizu Kuniyoshi , Kondo Ryuichiro
Published: April 2011

Volatile constituents from natural plants have sometimes been used for the treatment of mental disorders, but the efficacy of many plants has not been determined. Here, we investigated the effects of the essential oil of the Siberian fir tree, Abies sibirica (Pinaceae), on individuals during and after performance of a sustained task on a visual display terminal (VDT). Participants who breathed air containing the essential oil showed prolonged heartbeat intervals and increased theta activity as measured by electroencephalography in the recovery period after the VDT task, but not during the task. The volatile constituents emitted from the essential oil of A. sibirica through the odorant delivery system for 40 min were α‐pinene (80.4 µg), santene (3.1 µg), tricyclene (2.4 µg), camphene (24.2 µg), β‐pinene (2.6 µg), myrcene (1.0 µg), δ‐3‐carene (14.4 µg), limonene (3.8 µg), and bornyl acetate (1.0 µg). These results show that the essential oil of A. sibirica reduced arousal levels after the VDT task, and might be useful for the prevention of VDT‐related mental health disturbance. Copyright © 2011 John Wiley & Sons, Ltd.