bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electron paramagnetic resonance and non‐resonant microwave absorption of single wall carbon nanotubes
Authors: Corzilius B. , Agarwal S. , Dinse K.‐P. , Hata K. 
Published: November 2007

AbstractSingle wall carbon nanotubes (SWNT) prepared by the “super growth” method exhibit electron paramagnetic resonance (EPR) signals, which originate from temperature activated detrapping of spins. Non‐resonant microwave absorption in the temperature range below 20 K is indicative for the opening of a small gap at the Fermi level for tubes of metallic character, which might indicate a transition into a superconducting (SC) state. The expected concurrent microwave field inhomogeneity has been detected by a transient nutation experiment. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The fundamental aspects of carbon nanotube metrology
Authors: Jorio Ado , Maciel Indhira O. , Araujo Paulo T. , Pesce Pedro B. C. , Pimenta Marcos A. 
Published: November 2007

AbstractThe accurate and reproducible measurement of the properties and performance characteristics of nanoscale materials, devices and systems are essential for quality and process control, commercial transactions and effective regulations. Scientists, manufacturers, governments, regulators and health and environmental protection agencies, will need measurement systems and evaluation protocols supported by well founded and robust standards, both physical and documentary. In this paper we discuss some fundamental aspects of the use of the resonance Raman spectroscopy of the radial breathing mode (RBM) of single wall carbon nanotubes (SWNTs) for metrological purposes. The achievements and problems are pointed, hoping for the development of procedures capable of making the promised nanotechnology revolution to become a reality. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Suspended carbon nanotube double quantum dots
Authors: Hüttel A. K. , Witkamp B. , van der Zant H. S. J. 
Published: November 2007

AbstractWe present fabrication of and the first measurements on partially suspended double quantum dots in a carbon nanotube. Our objective is to enhance the energy resolution for spectroscopy of the vibronic modes of a suspended nanotube. When fabricating our devices, nanotubes grown on‐chip are localized by AFM scanning, and subsequently contacted and gated with customized electrode geometries. First low‐temperature transport measurement results are discussed, where the double quantum dot characteristics are clearly recognizable in the measured current. In addition, we address current technological challenges and future plans. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Molecularly and atomically thin semiconductor and carbon nanoshells
Authors: Prinz V. Ya. , Seleznev V. A. 
Published: November 2007

AbstractApproaches to the formation of molecularly and atomically thin solid shells based on the transformation of thin planar films into more functional 3D precise shells are outlined. In the overview part of the present work several examples are given illustrating the possibility to obtain in bent films new effects never observed in planar films and to fabricate new nanomaterials from highly – ordered systems of interacting hybrid shells. In the original part of the article, we demonstrate the formation of nanoshells from monoatomic graphite layers, graphene, and also show the possibility of controllable detachment of graphene from graphite substrates with the help of AFM. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Preface: phys. stat. sol. (b) 244/11
Authors: Kuzmany Hans , Dinse Peter , Roth Siegmar , Thomsen Christian 
Published: November 2007

AbstractThe 21st Winterschool on Electronic Properties of Novel Materials (IWEPNM 2007) took place from 10 March to 17 March 2007. It continued the tradition of winterschools of this type in Kirchberg/Tirol in its well‐known atmosphere of collegiality and emphasis on scientific exchange between young and experienced scientists.The sessions at the IWEPNM 2007 focused on quantum information, carbon nanostructure synthesis, purification and separation, the characterization and properties of carbon nanostructures, fullerenes, endohedrals, and fullerides, excitons in carbon nanotubes, the chemical treatment of carbon nanotubes, nanotube filling and double‐walled nanotubes, graphite and graphene, non‐carbonaceous nanostructures, electron and heat transport in carbon nanostructures, composites with carbon nanotubes, and on theory and applications of these materials. This proceedings volume is divided into according sections.The program of the Winterschool was composed of invited oral presentations, poster presentations and mini‐workshops. The oral presentations were scheduled in morning and evening sessions, the mini‐workshops took place during the afternoons, and the posters were presented and discussed in two late‐evening sessions.In 2007 the Winterschool celebrated an anniversary: It had been of taking place for the 20th time at the Hotel Sonnenalp, a hotel ideally suited for the close interactions of international participants from many countries. We are grateful to the manager of Hotel Sonnenalp, Frau Edith Mayer, and her staff for the local arrangements as well as for her patience with many special requests during the meeting. We owe special thanks to the hotel staff for their careful organization of the celebration.The event benefited substantially from support of the Universität Wien and the Verein zur Förderung der Winterschulen in Kirchberg, as well as from numerous industrial sponsors. We greatly appreciate their financial contribution without which the meeting would have hardly become possible.Finally, special acknowledgments go to all contributors of the IWEPNM 2007 and to the authors of this volume, the proceedings of the Winterschool. Viera Skákalová was instrumental in compiling and editing the proceedings.In the name of all participants who have enjoyed the Winterschools since 1985 we express special thanks to Hans Kuzmany for his outstanding engagement in organizing the IWEP for so many years. His experience and advice will be needed for future Winterschools. The next Winterschool in this series will take place from 1 March to 8 March 2008, again in Kirchberg/Tirol, and will be organized by Christian Thomsen from Berlin.Wien, Darmstadt, Stuttgart, Berlin, 2007
Determination of four tobacco‐specific nitrosamines in mainstream cigarette smoke by gas chromatography/ion trap mass spectrometry
Authors: Zhou Jun , Bai Ruoshi , Zhu Yongfa 
Published: November 2007

AbstractA specific and sensitive method was developed and validated to quantitatively analyze four tobacco‐specific nitrosamines (TSNAs) in the particulate phase of mainstream cigarette smoke. Cigarette smoke particulate matter was collected according to ISO 4387. The particulate matter was extracted with acetic ether, cleaned up with a Supelclean ENVI‐Carb silod‐phase extraction (SPE) cartridge, concentrated under the protection of nitrogen and analyzed by gas chromatography (GC)/ion trap mass spectrometry (MS) with a very‐low‐flow‐loss column (VF‐17 MS) in MSn mode using N‐nitrosopentyl‐3‐picolylamine (NNPA) as an internal standard. TSNAs were identified by chromatographic retention time, matching the spectra of the standards and the samples and the consistency of the ratio of the abundance of the ions detected in the standards and the samples. Limits of detection of each TSNA varied from 0.01 to 0.06 ng/cig. A linear calibration range for this method is large enough to measure TSNA levels in cigarette smoke. The recovery of each TSNA was from 91.5 to 102.7%. The method achieved excellent reproducibility (RSD: 1.8–4.8% for intra‐assay, 3.4–7.1% for inter‐assay). It also shows no evidence of artifact formation. This method is very suitable for the routine detection of TSNAs in mainstream cigarette smoke. Copyright © 2007 John Wiley & Sons, Ltd.
Magnetic resonance imaging‐compatible, three‐degrees‐of‐freedom joystick for surgical robot
Authors: Harja Juha , Tikkanen Jussi , Sorvoja Hannu , Myllylä Risto 
Published: November 2007

AbstractBackgroundThis paper presents a magnetic resonance (MR) compatible joystick for controlling a surgical robot arm. The surgical robot can be used to assist the surgeon in high precision neurosurgery tasks. Conventional joysticks cannot be used in magnetic resonance imaging (MRI) environments, because they generally contain ferromagnetic materials such as iron, which create distortions in MR images. Moreover, dangerous situations may arise, when an object containing ferromagnetic materials passes through the strong magnetic field of an imaging device. Currents generated by device electronics produce magnetic fields that distort MR images.MethodsOperation of the joystick described here is based on measuring light intensity. Optical fibres are used for target illumination and for transmitting the reflected light. Their use enables the joystick electronics to be kept at a safe distance from the imaging machine.ResultsExperimental results prove that the joystick can be constructed on the presented operating principle using the designed mechanical structure. When the joystick was placed 15 cm away from the phantom object, it didn't cause any distortion to the MR image.ConclusionsThe developed joystick can be used in an MRI environment. However, further development need to be done in order to avoid losses caused by bending optical fibres. Copyright © 2007 John Wiley & Sons, Ltd.
Extracting physically nonexistent contours
Authors: Yasuda Hiroyuki , Ando Kazuhisa , Ohnishi Noboru , Sugie Noboru 
Published: November 2007

AbstractA model of the human vision system is proposed which seems to be related to highly reliable extraction of contours from an original image. In other words, an algorithm is proposed for automatically generating physically nonexistent subjective contours. This algorithm consists of the following five steps: extracting physical contours, determining candidate points through which subjective contours pass, determining a direction of subjective contours at each candidate point, determining pairs of candidate points to be connected by subjective contours, and generating curves connecting each pair of candidate points. This algorithm was applied to various figures containing line segments, and it was found that the same contours as the subjective contours perceived by human beings could be generated automatically. Further, this algorithm was applied to a figure of lines consisting only of external contours at which several convex polygons overlap each other. Then, internal contours could be extracted in the overlapping parts of objects and separate constituent polygons.
Estimation of 3‐D shape from shading by using a constraint at zero‐crossing
Authors: Sangaworasil Manas , Kojima Kouichi , Atsuta Kiyoaki , Kondo Shozo 
Published: November 2007

AbstractThis paper describes estimations of the shape of a three‐dimensional (3‐D) object from a gray‐level 2‐D image, i.e., “shape from shading.” The fact that the Ikeuchi‐Horn iterative method produces an error when this is applied to the estimation of an object having a concave surface is shown. A new method using a constraint on a zero‐crossing is proposed which can be applied to such an object. Examples of application of the proposed method are shown to confirm its effectiveness, from a case where several interpretations are possible from a single gray‐level 2‐D image, the proposed method can estimate all of them. Examples of such cases also are shown.
Identification for complicated shape objects by using stochastic fractal variables—categorizing dust particles on LSI wafer surface
Authors: Kamijo Masayoshi , Aihara Shin‐Ichi 
Published: November 2007

AbstractImproving the yield and stability of LSI wafer production requires that the number of dust particles during every process of the production be decreased. To do this, we must develop a method of identifying dust particles. However, the current method of inspecting LSI wafers depends on human judgment; this makes it difficult to develop an algorithm to identify dust particles with complex shapes because mathematical models of dust particles have not been created. With this study, we propose the so‐called “stochastic fractal variable” to make the mathematical model and identify the dust particles by using the maximum‐likelihood method. Furthermore, we confirm the effectiveness of the identification method we propose by categorizing actual data.
Semiparametric Bayesian analysis of structural equation models with fixed covariates
Authors: Lee Sik‐Yum , Lu Bin , Song Xin‐Yuan 
Published: November 2007

AbstractLatent variables play the most important role in structural equation modeling. In almost all existing structural equation models (SEMs), it is assumed that the distribution of the latent variables is normal. As this assumption is likely to be violated in many biomedical researches, a semiparametric Bayesian approach for relaxing it is developed in this paper. In the context of SEMs with covariates, we provide a general Bayesian framework in which a semiparametric hierarchical modeling with an approximate truncation Dirichlet process prior distribution is specified for the latent variables. The stick‐breaking prior and the blocked Gibbs sampler are used for efficient simulation in the posterior analysis. The developed methodology is applied to a study of kidney disease in diabetes patients. A simulation study is conducted to reveal the empirical performance of the proposed approach. Supplementary electronic material for this paper is available in Wiley InterScience at http://www.mrw.interscience.wiley.com/suppmat/1097‐0258/suppmat/. Copyright © 2007 John Wiley & Sons, Ltd.
Fast Mass Transport Through Carbon Nanotube Membranes
Authors: Verweij Henk , Schillo Melissa C. , Li Ju 
Published: November 2007

AbstractThe May 19, 2006 issue of Science included a paper by Holt et al.1 on “Fast Mass Transport Through Sub‐2‐Nanometer Carbon Nanotubes”. The paper was also featured on the cover, showing methane molecules translating inside a carbon nanotube (CNT). The authors explained how they prepared 2–6‐μm thin membranes consisting of double‐walled carbon nanotubes (DWNTs) all aligned perpendicular to the apparent membrane surface. These tubes are open at both ends and the space between the tubes is filled with dense Si3N4. Pure gas and water fluxes were measured at room temperature with the application of a small pressure difference. Interpretation of the results led to the conclusion that the membranes showed much higher fluxes than what was estimated from Knudsen gas diffusion and Poiseuille viscous flow models. The membranes have a straight‐channel morphology with a narrow pore‐size distribution and exceptionally smooth pore walls. The unusual geometry and surface properties make it difficult to compare the membrane’s properties with common membranes but there is no question that the mass transport in the aligned DWNTs is fast indeed. To appreciate how fast, we will consider their transport properties starting from the perspective of “conventional” porous membrane technology. Recent molecular dynamics simulations suggest that none of the classic models for gas (Knudsen) and water (Poiseuille) permeation work in a meaningful way for these nanotube membranes, and new models are needed.
Model checking action system refinements
Authors: Smith Graeme , Winter Kirsten 
Published: November 2007

Abstract

Action systems provide a formal approach to modelling parallel and reactive systems. They have a well established theory of refinement supported by simulation-based proof rules. This paper introduces an automatic approach for verifying action system refinements utilising standard CTL model checking. To do this, we encode each of the simulation conditions as a
simulation machine
, a Kripke structure on which the proof obligation can be discharged by checking that an associated CTL property holds. This procedure transforms each simulation condition into a model checking problem. Each simulation condition can then be model checked in isolation, or, if desired, together with the other simulation conditions by combining the simulation machines and the CTL properties.
In Vitro Structural and Functional Evaluation of Gold Nanoparticles Conjugated Antibiotics
Authors: Saha Biswarup , Bhattacharya Jaydeep , Mukherjee Ananda , Ghosh AnupKumar , Santra ChittaRanjan , Dasgupta Anjan K , Karmakar Parimal 
Published: November 2007

AbstractBactericidal efficacy of gold nanoparticles conjugated with ampicillin, streptomycin and kanamycin were evaluated. Gold nanoparticles (Gnps) were conjugated with the antibiotics during the synthesis of nanoparticles utilizing the combined reducing property of antibiotics and sodium borohydride. The conjugation of nanoparticles was confirmed by dynamic light scattering (DLS) and electron microscopic (EM) studies. Such Gnps conjugated antibiotics showed greater bactericidal activity in standard agar well diffusion assay. The minimal inhibitory concentration (MIC) values of all the three antibiotics along with their Gnps conjugated forms were determined in three bacterial strains,Escherichia coli DH5α,Micrococcus luteusandStaphylococcus aureus. Among them, streptomycin and kanamycin showed significant reduction in MIC values in their Gnps conjugated form whereas; Gnps conjugated ampicillin showed slight decrement in the MIC value compared to its free form. On the other hand, all of them showed more heat stability in their Gnps conjugated forms. Thus, our findings indicated that Gnps conjugated antibiotics are more efficient and might have significant therapeutic implications.
Industrial Home Laundry Closed Loop Cleaning Process
Authors: Scamehorn John F. , Tucker Edwin E. , Gecol Hatice , Komesvarakul Napaporn , Serventi Lorena K. , Raney Kirk H. , Capps Stephen F. 
Published: November 2007

AbstractThis study presents a method to develop an efficient and economical system for cleaning home laundry on a commercial scale with both water and chemical (detergent) reuse. The experiments were done using an industrial‐type horizontal‐axis machine, two leading consumer heavy‐duty liquid laundry detergents, one I&I detergent formulation, and chlorine bleach. The technical feasibility of reusing laundry water at high levels without significant deterioration in detergency was established in this study. Warm water (40 °C) was used in the wash cycle, and cold water (29 °C) was used for three rinse cycles. In the integrated process, waters from wash and rinse steps were treated using tubular microfiltration units with 0.1 μm pore size to remove particles and emulsion droplets. These recovered waters were recycled to be reused. In addition, water recycled from the wash step contains surfactants that can be reused. In order to simulate a large‐scale industrial laundry operation at steady‐state, the batch process used here was operated six times in sequence; wash and rinse waters were filtered after each cycle and reused in the next wash cycle. The surfactant recovery is over 40%. Soiled test strips were used to measure the percentage of soil removal after the wash/filtration sequence for stains and various liquid or particulate soils. The soil removal remained practically constant under simulated steady‐state conditions even with water recoveries of nearly 90%. Softness of towels remained unchanged when recycled water was used in this process. Chlorine carry‐over from white laundry to the wash process was shown to be minimal. This is important to avoid color fading in mixed loads upon reuse since water is not segregated for colored laundry versus white laundry. Hardness ions can precipitate fatty acids which reduce flux during filtration and decrease surfactant recovery. Preliminary analysis of the different formulations used indicates that an all‐nonionic formulation may be best suited to this recycling process.
Genistein and daidzein induced apoA-1 transactivation in hepG2 cells expressing oestrogen receptor-α
Authors: Yuen Yee M. , Leung Lai K. 
Published: November 2007

Studies have shown that soya consumption has been associated with low incidence of CVD. Because the chemical structures of soya isoflavones are similar to oestrogen, the beneficial outcome may be attributed to the oestrogenicity of these compounds. In this study, effect of the soya isoflavone genistein on the mRNA expression of apoA-1 in the human hepatoma HepG2 cell was investigated. Without oestrogen receptor (ER) α transfection, soya isoflavones in the physiological range had no effect on the apoA-1 transcription. Once ERα was ectopically expressed in these cells, soya isoflavone dramatically increased the apoA-1 mRNA abundance quantified by real-time PCR.ApoA-1-reporter assays with plasmid constructed from the 5′-flanking segment upstream to the coding region revealed that the transactivation of theapoA-1promoter was induced by the soya isoflavone in HepG2 cells expressing ERα. This induction was reduced by the anti-oestrogen ICI 182780, but not the inhibitors of protein kinase (PK) C, PKA, or mitogen-activated PK. Based on the previously identified response elements on the promoter, a series of truncated promoter reporter plasmids were then constructed. An induction profile of genistein was built and insulin response core element at − 411 to − 404 appeared to be a potential site of interaction. This study illustrated that soya isoflavones at physiological concentrations could up regulate apoA-1 mRNA expression in ERα-transfected HepG2 cells.
Green tea catechin enhances cholesterol 7α-hydroxylase gene expression in HepG2 cells
Authors: Lee Mak-Soon , Park Ju-Yeon , Freake Hedley , Kwun In-Sook , Kim Yangha 
Published: November 2007

Green tea catechins are known to have hypocholesterolaemic effects in animals and human subjects. In the present study, we investigated the effects of green tea catechins on the mRNA level and promoter activity of hepatic cholesterol 7α-hydroxylase (CYP7A1), the rate-limiting enzyme in the conversion of cholesterol to bile acids, in human hepatoma cells. Real-time PCR assays showed that different catechins, ( − )-epicatechin gallate (ECG), ( − )-epigallocatechin-3-gallate (EGCG), ( − )-epigallocatechin (EGC) and ( − )-epicatechin (EC), up regulated the CYP7A1 mRNA level by 5·5-, 4·2-, 2·9- and 1·9-fold, respectively, compared with the control. The − 1312/+358 bp of the CYP7A1 promoter was subcloned into the pGL3 basic vector that includes luciferase as a reporter gene. ECG or EGCG significantly increased CYP7A1 promoter activity by 6·0- or 4·0-fold, respectively, compared with the control. Also, EGCG stimulated CYP7A1 at both mRNA level and promoter activity in a dose-dependent manner. These results suggest that the expression of the CYP7A1 gene may be directly regulated by green tea catechins at the transcriptional level.