bluuebunny/crossref_metadata_2025 huggingface dataset:
Multiple aspect videos on demand delivery method
Authors: Mori Tatsuo , Matsumoto Mitsuji
Published: June 2006

The authors report on a method of delivering multiple aspect videos on demand as an application for broadband video communications. Their method is a client–server video delivery system with the user's terminal representing the client. Multiple aspect video programs such as for viewing sports or pursuing education are stored and managed. Each program consists of a group of synchronized video with several aspects, and contents are created and managed in units of individual aspect videos. The user selects a program from the terminal, then directs the delivery and playback of the desired aspect video by selecting the aspect video. Aspect switching is performed by switching to a separate aspect video while the progress of the video being played back is maintained. In addition to proposing $\def\circle#1{{\ooalign{\hfil\raise.07ex\hbox{#1}\hfil\crcr\mathhexbox20D}}}\circle{1}$ a method to control groups of program content, $\def\circle#1{{\ooalign{\hfil\raise.07ex\hbox{#1}\hfil\crcr\mathhexbox20D}}}\circle{2}$ a method to switching aspects at high speed using a quick start video, $\def\circle#1{{\ooalign{\hfil\raise.07ex\hbox{#1}\hfil\crcr\mathhexbox20D}}}\circle{3}$ a method to dynamically and efficiently set the quick start video, and $\def\circle#1{{\ooalign{\hfil\raise.07ex\hbox{#1}\hfil\crcr\mathhexbox20D}}}\circle{4}$ a method to reduce the displacement width with respect to the time displacement accompanying the connection to new and old aspect videos, the authors report on experimental results and a performance evaluation. © 2006 Wiley Periodicals, Inc. Syst Comp Jpn, 37(9): 47–62, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.20288
Afaf, a novel vesicle membrane protein, is related to acrosome formation in murine testis
Authors: Li Yin-Chuan , Hu Xiao-Qian , Zhang Ke-Ying , Guo Jian , Hu Zhao-Yuan , Tao Shi-Xin , Xiao Li-Juan , Wang Qing-Zhong , Han Chun-Sheng , Liu Yi-Xun
Published: June 2006

As a cell‐specific organelle, acrosome (Acr) and its formation are an important event for spermiogenesis. However, the Acr formation is far more complicated than has been proposed. In this study, we have cloned a novel membrane protein Afaf (Acr formation associated factor) that was expressed abundantly in the round spermatids, localized in the inner and outer membrane of forming Acrs, and declined in the maturing Acrs. In the transfected Hela cells, Afaf protein was localized in the plasma membrane, EEA1‐positive early endosomes (EEs) and occasionally in the nuclei. Therefore, we propose that EEs and plasma membrane may be also directly involved in the Acr biogenesis.
Pregnancy complicated with Buerger's disease
Authors: Kikuchi N. , Kanai M. , Kita N. , Mitsuhashi Y. , Konishi I.
Published: June 2006

Buerger's disease is an inflammatory occlusive vascular disorder involving small‐ and medium‐sized arteries in the distal extremities and is usually complicated with thrombophlebitis. Since Buerger's disease develops most frequently in men who smoke, pregnancy complicated with this disease is extremely rare. Only three pregnancies have been reported previously. All cases indicate that Buerger's disease worsens during pregnancy. However, anti‐coagulant therapy appeared to be effective in this case. Accordingly, careful observation is mandatory in pregnancies complicated with Buerger's disease.
When Robots Are Good: Fully Automated Thermo LAS Robotic Assay System with Dual FLIPRTETRA and TAP SelecT Robotic Cell Culture System
Authors: Soloveva Veronica , Larocque James , Mckillip Edward
Published: June 2006

Cell-based assays for identification of biologically active small molecules from chemical libraries are becoming increasingly popular for HTS aimed at a variety of drug targets. Functional assays require good coordination between several independent processes during the run. This article describes our custom designed, fully automated Thermo LAS robotic system with integrated FLIPRTETRA and several additional peripheral elements such as a BioTek ELX washer unit, a PE Evolution pipettor, and PE FlexDrop dispenser. The Thermo LAS robotic control software, Polara, ensures that each and every plate of sensitive cells in a large batch experiences the same procedure as an individual plate assayed in the hands of a scientist. Such robotic systems can process hundreds of plates a day and require large-scale automated support for cell preparation. The TAP SelecT is an automated robotic system that can plate 100– 300 plates of cells per day with defined accuracy and precision. In addition to plating cells, SelecT can also pass and expand cell lines. Here, we present a case study of a GPCR-mediated Ca-flux assay, where this robotic team enables high-throughput logistics even for an extremely sensitive cell-based assay.
Need for Simulation-Based Design Analysis and Optimization
Authors: Krishnamoorthy S. , Bedekar A.S. , Feng J J. , Sundaram S.
Published: June 2006

Recent advances in microfabrication techniques, sensing methods, and miniaturization have enabled automated analysis of samples using microfluidic systems. Each unique application requires successful custom development of integrated lab-on-a-chip devices. This involves design, analysis and characterization of individual components, (pumps, valves, mixers, separators, sensors) and the integrated system. In this regard, first-principle-based simulations of the underlying complex multiphysics phenomena can provide detailed understanding of device function. An overview of modeling and simulation-based analysis for the design and development of microfluidic devices is presented. In particular, we highlight some key factors affecting the performance of lab-on-a-chip systems such as surface tension effects, analyte dispersion, Joule heating, and mass transport limitations, and delineate the parameters that influence them. The limitations of these modeling techniques and future needs are discussed.
Toward a model of strategic outsourcing
Authors: Holcomb Tim R. , Hitt Michael A.
Published: June 2006

Acknowledging efficiency motives, firms have increasingly turned to outsourcing in an effort to capture cost savings. Transaction cost theory (TCT) has been the dominant means of explaining outsourcing as an economizing approach whereby cost efficiencies are achieved by assigning transactions to different governance mechanisms. Recent research has used the resource‐based view (RBV) to examine the role of specialized capabilities as a potential source of value creation in relationships between firms. Although research in supply chain management has expanded substantially, only limited applications of TCT and the RBV are available, especially in the field of operations management. We extend both perspectives to explain conditions leading to strategic outsourcing.
Bridging organization theory and supply chain management: The case of best value supply chains
Authors: Ketchen David J. , Hult G. Tomas M.
Published: June 2006

Rivalry is increasingly being contested at the supply chain level of analysis. Rather than competing “firm versus firm,” today's organizations are battling “supply chain versus supply chain.” Within this context, best value supply chains are emerging as a means to create competitive advantages and superior performance. While traditional supply chains often focus primarily on one key outcome such as speed or cost, best value supply chains excel along an array of uniquely integrated priorities—cost, quality, speed, and flexibility. We describe how key organizational theories help to distinguish traditional supply chains from best value supply chains. To provide a foundation for future inquiry, we offer theory‐based research questions that are focused on best value supply chains.
Late Holocene forest dynamics, volcanism, and climate change at Whitewing Mountain and San Joaquin Ridge, Mono County, Sierra Nevada, CA, USA
Authors: Millar Constance I. , King John C. , Westfall Robert D. , Alden Harry A. , Delany Diane L.
Published: June 2006

Deadwood tree stems scattered above treeline on tephra-covered slopes of Whitewing Mtn (3051 m) and San Joaquin Ridge (3122 m) show evidence of being killed in an eruption from adjacent Glass Creek Vent, Inyo Craters. Using tree-ring methods, we dated deadwood to AD 815–1350 and infer from death dates that the eruption occurred in late summer AD 1350. Based on wood anatomy, we identified deadwood species as Pinus albicaulis, P. monticola, P. lambertiana, P. contorta, P. jeffreyi, and Tsuga mertensiana. Only P. albicaulis grows at these elevations currently; P. lambertiana is not locally native. Using contemporary distributions of the species, we modeled paleoclimate during the time of sympatry to be significantly warmer (+3.2°C annual minimum temperature) and slightly drier (−24 mm annual precipitation) than present, resembling values projected for California in the next 70–100 yr.
Risk factors associated with Enteromyxum scophthalmi (Myxozoa) infection in cultured turbot, Scophthalmus maximus (L.)
Authors: QUIROGA M. I. , REDONDO M. J. , SITJÀ-BOBADILLA A. , PALENZUELA O. , RIAZA A. , MACÍAS A. , VÁZQUEZ S. , PEREZ A. , NIETO J. M. , ALVAREZ-PELLITERO P.
Published: June 2006

An epidemiological cohort study of Enteromyxum scophthalmi in cultured turbot was performed on a farm in North Western Spain. Four different ongrowing stocks (A, B, C, D) were monitored monthly until market size. Fish from stocks C and D were divided into 2 subgroups, receiving filtered (CF and DF) or unfiltered (CUF and DUF) water. The lack of water filtration was positively associated with infection prevalence, as all fish kept in filtered water remained uninfected. Parasite abundance varied seasonally (P<0·05) in stock B and subgroup CUF. Infection was also associated (P<0·05) with host weight, and the highest prevalences and intensities were detected in 101–200 g and 201–300 g fish. Distribution pattern of E. scophthalmi in subgroups CUF and DUF had a variance higher than the mean, indicating overdispersion. The minimum period necessary for the first detection of the parasite and for the appearance of disease symptoms and mortality, varied depending on the stock and introduction date, although a long pre-patent period was always observed. Several factors, such as host density, parasite recruitment and parasite-induced fish mortality can contribute to the observed distribution pattern. Risk factors found to be associated with E. scophthalmi infection, including water quality and accumulation of infective stages in the culture tanks, should be considered when designing control strategies to prevent the introduction and spread of infective stages in the facilities.
Does using potting mix make you sick? Results from a Legionella longbeachae case-control study in South Australia
Authors: O'CONNOR B. A. , CARMAN J. , ECKERT K. , TUCKER G. , GIVNEY R. , CAMERON S.
Published: June 2006

A case-control study was performed in South Australia to determine if L. longbeachae infection was associated with recent handling of commercial potting mix and to examine possible modes of transmission. Twenty-five laboratory-confirmed cases and 75 matched controls were enrolled between April 1997 and March 1999. Information on underlying illness, smoking, gardening exposures and behaviours was obtained by telephone interviews. Recent use of potting mix was associated with illness (OR 4·74, 95% CI 1·65–13·55, P=0·004) in bivariate analysis only. Better predictors of illness in multivariate analysis included poor hand-washing practices after gardening, long-term smoking and being near dripping hanging flower pots. Awareness of a possible health risk with potting mix protected against illness. Results are consistent with inhalation and ingestion as possible modes of transmission. Exposure to aerosolized organisms and poor gardening hygiene may be important predisposing factors to L. longbeachae infection.
Research in UK architecture schools – an institutional perspective
Authors: Jenkins Paul , Forsyth Leslie , Smith Harry
Published: June 2006

The development of architectural knowledge and research in Britain offers a context in which to interpret a recent study of research across UK architectural schools.
Gottfried Semper's primitive hut as an act of self-creation
Authors: Hale Jonathan A.
Published: June 2006

Bergson's concept of duration encapsulates a philosophy of the experience of time – which could also explain how spaces acquire temporal richness through construction and use.
A reevaluation of tectonic discrimination diagrams and a new probabilistic approach using large geochemical databases: Moving beyond binary and ternary plots
Authors: Snow Cameron A.
Published: June 2006

Statistically rigorous confidence intervals calculated from analyses of basaltic volcanic samples obtained from two large geochemical databases (PetDB and GEOROC) demonstrate that published binary and ternary discrimination diagrams seldom correctly classify samples from mid‐ocean ridges, island arcs, and ocean islands with better than 60% accuracy. The confidence intervals provide a measure of certainty that was previously absent from these diagrams, allowing for a more robust analysis of results. A new probabilistic method for geochemical discrimination is developed using the geochemical databases. The new method is N‐dimensional and uses a priori data to construct probability distribution functions from which a posteriori probabilities are generated. Tests of the new method demonstrate single analysis classification success rates for volcanic rocks from island arcs to be 83%, from ocean islands to be 75%, and from mid‐ocean ridges to be 76%.
High‐resolution subduction zone seismicity and velocity structure beneath Ibaraki Prefecture, Japan
Authors: Shelly David R. , Beroza Gregory C. , Zhang Haijiang , Thurber Clifford H. , Ide Satoshi
Published: June 2006

We use double‐difference tomography and waveform‐derived cross‐correlation differential times to estimate earthquake locations and P and S wave velocity structure in the subduction zone under Ibaraki and neighboring prefectures of north central Honshu. We find evidence in both earthquake hypocenters and the velocity structure that the Philippine Sea plate, or perhaps a microplate fragment, may be caught between the subducting Pacific plate and overriding Okhotsk plate in this region. In the southern part of the study area, we find a zone of interplate events extending as deep as 60 km, forming a distinct lineation in cross section. Focal mechanisms support the interpretation that these are low‐angle, subduction interface events. We infer that these events probably occur on the interface between the Pacific and Philippine Sea plates rather than between the Pacific and Okhotsk plates. In the upper part of the downgoing Pacific plate, we find a zone of high Vp/Vs ratio (∼1.95), which may be explained by high pore fluid pressures within the subducting crust. At a depth of 60–80 km, this region of high Vp/Vs appears to diffuse into the overlying mantle wedge, possibly indicating the upward release of fluids from the slab.
Channel‐reach morphology dependence on energy, scale, and hydroclimatic processes with implications for prediction using geospatial data
Authors: Flores Alejandro N. , Bledsoe Brian P. , Cuhaciyan Christopher O. , Wohl Ellen E.
Published: June 2006

Channel types found in mountain drainages occupy characteristic but intergrading ranges of bed slope that reflect a dynamic balance between erosive energy and channel boundary resistance. Using a classification and regression tree (CART) modeling approach, we demonstrate that drainage area scaling of channel slopes provides better discrimination of these forms than slope alone among supply‐ and capacity‐limited sites. Analysis of 270 stream reaches in the western United States exhibiting four common mountain channel types reveals that these types exist within relatively discrete ranges of an index of specific stream power. We also demonstrate associations among regional interannual precipitation variability, discharge distribution skewness, and means of the specific stream power index of step‐pool channels. Finally, we discuss a conceptual methodology for predicting ecologically relevant morphologic units from digital elevation models at the network scale based on the finding that channel types do not exhibit equal energy dissipation.
Improved cardiovascular function with aminoguanidine in DOCA‐salt hypertensive rats
Authors: Chan Vincent , Hoey Andrew , Brown Lindsay
Published: June 2006

The ability of aminoguanidine (AG), an inhibitor of collagen crosslinking, to prevent changes in cardiac and vascular structure and function has been determined in the deoxycorticosterone acetate (DOCA)‐salt hypertensive rat as a model of the cardiovascular remodelling observed in chronic human hypertension.

Uninephrectomized rats (UNX) administered DOCA (25 mg every fourth day s.c.) and 1% NaCl in drinking water for 28 days developed cardiovascular remodelling shown as systolic hypertension, left ventricular hypertrophy, increased thoracic aortic and left ventricular wall thickness, increased left ventricular inflammatory cell infiltration together with increased interstitial collagen and increased passive diastolic stiffness, impaired contractility, prolongation of the action potential duration and vascular dysfunction.

Treatment with AG (0.05–0.1% in drinking water; average 182±17 mg kg−1 day−1 in DOCA‐salt rats) decreased blood pressure (DOCA‐salt 176±4; +AG 144±5 mmHg; *P<0.05 vs DOCA‐salt), decreased left ventricular wet weights (DOCA‐salt 3.17±0.07; +AG 2.66±0.08 mg g−1 body wt*), reduced diastolic stiffness constant (DOCA‐salt 30.1±1.2; +AG 24.3±1.2* (dimensionless)), improved cardiac contractility (DOCA‐salt 1610±130; +AG 2370±100 mmHg s−1*) and vascular reactivity (3.4‐fold increase in maximal contractile response to noradrenaline, 3.2‐fold increase in maximal relaxation response to acetylcholine, twofold increase in maximal relaxation response to sodium nitroprusside) and prolonged the action potential duration at 50% repolarization without altering collagen content or inflammatory cell infiltration.

Thus, cardiovascular function in DOCA‐salt hypertensive rats can be improved by AG independent of changes in collagen content. This suggests that collagen crosslinking is an important cause of cardiovascular dysfunction during cardiovascular remodelling in hypertension.

British Journal of Pharmacology (2006) 148, 902–908. doi:10.1038/sj.bjp.0706801
Bradykinin modulates pacemaker currents through bradykinin B2 receptors in cultured interstitial cells of Cajal from the murine small intestine
Authors: Choi Seok , Park Do Young , Yeum Cheol Ho , Chang In Youb , You Ho Jin , Park Chan Guk , Kim Man Yoo , Kong In Deok , So Insuk , Kim Ki Whan , Jun Jae Yeoul
Published: June 2006

We studied the modulation of pacemaker activities by bradykinin in cultured interstitial cells of Cajal (ICC) from murine small intestine with the whole‐cell patch‐clamp technique. Externally applied bradykinin produced membrane depolarization in the current‐clamp mode and increased tonic inward pacemaker currents in the voltage‐clamp mode.

Pretreatment with bradykinin B1 antagonist did not block the bradykinin‐induced effects on pacemaker currents. However, pretreatment with bradykinin B2 antagonist selectively blocked the bradykinin‐induced effects. Also, only externally applied selective bradykinin B2 receptor agonist produced tonic inward pacemaker currents and ICC revealed a colocalization of the bradykinin B2 receptor and c‐kit immunoreactivities, but bradykinin B1 receptors did not localize in ICC.

External Na+‐free solution abolished the generation of pacemaker currents and inhibited the bradykinin‐induced tonic inward current. However, a Cl− channel blocker (DIDS) did not block the bradykinin‐induced tonic inward current.

The pretreatment with Ca2+‐free solution and thapsigargin, a Ca2+‐ATPase inhibitor in endoplasmic reticulum, abolished the generation of pacemaker currents and suppressed the bradykinin‐induced action.

Chelerythrine and calphostin C, protein kinase C inhibitors or naproxen, an inhibitor of cyclooxygenase, did not block the bradykinin‐induced effects on pacemaker currents.

These results suggest that bradykinin modulates the pacemaker activities through bradykinin B2 receptor activation in ICC by external Ca2+ influx and internal Ca2+ release via protein kinase C‐ or cyclooxygenase‐independent mechanism. Therefore, the ICC are targets for bradykinin and their interaction can affect intestinal motility.

British Journal of Pharmacology (2006) 148, 918–926. doi:10.1038/sj.bjp.0706806
Acetyl‐keto‐β‐boswellic acid inhibits cellular proliferation through a p21‐dependent pathway in colon cancer cells
Authors: Liu Jian‐Jun , Huang Baohua , Hooi Shing Chuan
Published: June 2006

Although there is increasing evidence showing that boswellic acid might be a potential anticancer agent, the mechanisms involved in its action are unclear.

In the present study, we showed that acetyl‐keto‐β‐boswellic acid (AKBA) inhibited cellular growth in several colon cancer cell lines. Cell cycle analysis by flow cytometry showed that cells were arrested at the G1 phase after AKBA treatment.

Further analysis showed that cyclin D1 and E, CDK 2 and 4 and phosphorylated Rb were decreased in AKBA‐treated cells while p21 expression was increased.

The growth inhibitory effect of AKBA was dependent on p21 but not p53. HCT‐116 p53−/−cells were sensitized to the apoptotic effect of AKBA, suggesting that p21 may have protected cells against apoptosis by inducing a G1 arrest.

In conclusion, we have demonstrated that AKBA inhibited cellular growth in colon cancer cells. These findings may have implications to the use of boswellic acids as potential anticancer agents in colon cancer.

British Journal of Pharmacology(2006)148, 1099–1107. doi:10.1038/sj.bjp.0706817
Simulation studies of the protein-water interface. II. Properties at the mesoscopic resolution
Authors: Rudas T. , Schröder C. , Boresch S. , Steinhauser O.
Published: June 2006

We report molecular dynamics (MD) simulations of three protein-water systems (ubiquitin, apo-calbindin D9K, and the C-terminal SH2 domain of phospholipase C-γ1), from which we compute the dielectric properties of the solutions. Since two of the proteins studied have a net charge, we develop the necessary theory to account for the presence of charged species in a form suitable for computer simulations. In order to ensure convergence of the time correlation functions needed for the analysis, the minimum length of the MD simulations was 20ns. The system sizes (box length, number of waters) were chosen so that the resulting protein concentrations are comparable to experimental conditions. A dielectric component analysis was carried out to analyze the contributions from protein and water to the frequency-dependent dielectric susceptibility χ(ω) of the solutions. Additionally, an even finer decomposition into protein, two solvation shells, and the remaining water (bulk water) was carried out. The results of these dielectric decompositions were used to study protein solvation at mesoscopic resolution, i.e., in terms of protein, first and second solvation layers, and bulk water. This study, therefore, complements the structural and dynamical analyses at molecular resolution that are presented in the companion paper. The dielectric component contributions from the second shell and bulk water are very similar in all three systems. We find that the proteins influence the dielectric properties of water even beyond the second solvation shell, in agreement with what was observed for the mean residence times of water molecules in protein solutions. By contrast, the protein contributions, as well as the contributions of the first solvation shell, are system specific. Most importantly, the protein and the first water shell around ubiquitin and apo-calbindin are anticorrelated, whereas the first water shell around the SH2 domain is positively correlated.
p
-type metal-base transistor
Authors: Delatorre R. G. , Munford M. L. , Zandonay R. , Zoldan V. C. , Pasa A. A. , Schwarzacher W. , Meruvia M. S. , Hümmelgen I. A.
Published: June 2006

In this work we present data from a novel p-type metal-base transistor with common-base gain α∼1, fabricated at ambient temperature and pressure by electrodepositing sequentially on a p-type Si collector, a Co base and a Cu2O emitter. The high gain and the dependence of potential between emitter and base (VEB) on the potential between collector and base (VCB) when the emitter current (IE) is held constant both suggest that the device functions as a natural permeable base transistor for very thin metal bases.
Is the Ewald summation still necessary? Pairwise alternatives to the accepted standard for long-range electrostatics
Authors: Fennell Christopher J. , Gezelter J. Daniel
Published: June 2006

We investigate pairwise electrostatic interaction methods and show that there are viable computationally efficient (O(N)) alternatives to the Ewald summation for typical modern molecular simulations. These methods are extended from the damped and cutoff-neutralized Coulombic sum originally proposed by Wolf et al. [J. Chem. Phys. 110, 8255 (1999)]. One of these, the damped shifted force method, shows a remarkable ability to reproduce the energetic and dynamic characteristics exhibited by simulations employing lattice summation techniques. Comparisons were performed with this and other pairwise methods against the smooth particle-mesh Ewald summation to see how well they reproduce the energetics and dynamics of a variety of molecular simulations.
Integrated simulation of the generation and transport of proton beams from laser-target interaction
Authors: Welch D. R. , Rose D. V. , Cuneo M. E. , Campbell R. B. , Mehlhorn T. A.
Published: June 2006

High current, energetic protons are produced by irradiating thin metal foils with intense lasers. Here, the laser plasma interaction produces relativistic electrons at the critical surface. These electrons propagate through the foil and create a space-charge cloud that accelerates proton contaminants on the back side. Self-consistent electromagnetic simulations of this process using a hybrid particle-in-cell code show the importance of detailed modeling of the electron production and transport, as well as the distributed acceleration and spatial distribution of the protons well off the foil surface. The protons become neutralized by energetic electrons resupplied by the expanding plume of the back surface, not by energetic electrons thermalizing within the proton cloud. Details of the laser-plasma interaction simulation techniques and implications for ion-driven fast ignition are also discussed.
High contrast organic light-emitting devices with improved electrical characteristics
Authors: Zhou Y. C. , Ma L. L. , Zhou J. , Gao X. D. , Wu H. R. , Ding X. M. , Hou X. Y.
Published: June 2006

High contrast organic light-emitting devices with low-reflection cathodes are fabricated. The cathode consists of a semitransparent metal layer, a phase-changing (PC) layer, and a reflective metal layer. With Al doped tris(8-hydroxyquinoline) aluminum as PC layer, devices exhibit the average reflectivity of the ambient light as low as about 13%. And its electrical characteristics are almost identical to that of a conventional device, although the thickness is increased by 70%. The improvement in conductivity could be attributed to the conductive Al cluster distributed in the organic matrix.
Ferromagnetic formation of two phases due to MnP and InMn3 from InMnP:Zn implanted with Mn (10at.%)
Authors: Shon Yoon , Lee Sejoon , Jeon H. C. , Lee S.-W. , Kim D. Y. , Kang T. W. , Kim Eun Kyu , Fu D. J. , Fan X. J. , Yoon Chong S. , Kim C. K.
Published: June 2006

InMnP:Zn samples implanted with Mn (10at.%) were annealed at 350°C for 60s and at 450°C for 30s. Using transmittance electron microscopy, both single crystalline and polycrystalline structures containing MnP and InMn3 sized ∼20nm were observed depending on the annealing condition. These samples exhibited two different Curie temperatures: TC1 at 291K and another well above 291K. The high temperature-ferromagnetic behavior up to TC1 and above TC2 is believed to have originated from two magnetic MnP and InMn3 phases, respectively.
Plasma treatment of diamond nanoparticles for dispersion improvement in water
Authors: Yu Qingsong , Kim Young Jo , Ma Hongbin
Published: June 2006

Low-temperature plasmas of methane and oxygen mixtures were used to treat diamond nanoparticles to modify their surface characteristics and thus improve their dispersion capability in water. It was found that the plasma treatment significantly reduced water contact angle of diamond nanoparticles and thus rendered the nanoparticles with strong water affinity for dispersion enhancement in polar media such as water. Surface analysis using Fourier transform infrared spectroscopy confirmed that polar groups were imparted on nanoparticle surfaces. As a result, improved suspension stability was observed with plasma treated nanoparticles when dispersed in water.
Reinforcement of semicrystalline polymers with collagen-modified single walled carbon nanotubes
Authors: Bhattacharyya Sanjib , Salvetat Jean-Paul , Saboungi Marie-Louise
Published: June 2006

We report on the enhancement of the mechanical properties of single wall carbon nanotube (SWNT)-polyvinyl alcohol (PVA) composites through functionalization of SWNTs with denatured collagen. In addition to improving compatibility with the matrix, the denatured collagen layer was found to increase the PVA matrix crystallinity, which results in a dramatic enhancement of the Young’s modulus (260%), tensile strength (300%), and toughness (700%) well above what can be expected with the classical rule of mixture. A supramolecular organization at the interface is associated with an increase of PVA crystallinity as shown by the x-ray diffraction and differential scanning calorimetry.
Elastic and surface energies: Two key parameters for CdSe quantum dot formation
Authors: Robin Ivan-Christophe , André Régis , Bougerol Catherine , Aichele Thomas , Tatarenko Serge
Published: June 2006

The two-dimensional–three-dimensional transition of a strained CdSe layer on (001) ZnSe induced by the use of amorphous selenium is studied. To precisely control the thickness of the CdSe layer, atomic layer epitaxy growth mode is used. Atomic force microscopy and reflection high-energy electron diffraction measurements reveal the formation of CdSe islands when 3 ML (monolayers) of CdSe, corresponding to the critical thickness, are deposited. When only 2.5 ML of CdSe are deposited another relaxation mechanism is observed, leading to the appearance of strong undulations on the surface. For a 3 ML thick CdSe layer, transmission electron microscopy images indicate that the formation of the islands occurs only after the amorphous selenium desorption.
Tuning nonlinearity, dynamic range, and frequency of nanomechanical resonators
Authors: Kozinsky I. , Postma H. W. Ch. , Bargatin I. , Roukes M. L.
Published: June 2006

We explore an electrostatic mechanism for tuning the nonlinearity of nanomechanical resonators and increasing their dynamic range for sensor applications. We also demonstrate tuning the resonant frequency of resonators both upward and downward. A theoretical model is developed that qualitatively explains the experimental results and serves as a simple guide for design of tunable nanomechanical devices.
Substrate effects on the electronic properties of an organic/organic heterojunction
Authors: Tang J. X. , Lau K. M. , Lee C. S. , Lee S. T.
Published: June 2006

The electronic structures of copper-phthalocyanine/tris(8-hydroxyquinoline) aluminum (CuPc∕Alq3) heterojunctions on Mg and indium tin oxide (ITO) substrates have been studied by photoemission spectroscopy. While the typical vacuum energy level lineup occurred at the CuPc∕Alq3 junction on ITO, the same junction formed on Mg displayed vastly different electronic structures, showing a 0.5eV band bending associated with the formation of a space charge layer. The substrate effects were explained by the proximity of the Mg’s Fermi level to the lowest unoccupied molecular orbital of CuPc, resulting in spontaneous charge transfer. The results show the feasibility of tuning the electronic properties of an organic heterojunction via the Fermi level of the substrate.
Long wavelength emitting InAs∕Ga0.85In0.15NxAs1−x quantum dots on GaAs substrate
Authors: Richter M. , Damilano B. , Duboz J.-Y. , Massies J. , Wieck A. D.
Published: June 2006

InAs quantum dots (QDs) overgrown by a Ga0.85In0.15NxAs1−x (0⩽x⩽0.017) layer have been realized on GaAs substrate by molecular beam epitaxy. When the nitrogen composition increases, the photoluminescence (PL) wavelength redshifts up to 1.52μm. It is shown that PL properties of InAs∕Ga0.85In0.15N0.012As0.988 QDs are improved by thermal annealing. Finally, 1.45μm PL emission with a 38.5meV full width at half maximum is obtained at room temperature.
Determination of thermal conductivity distribution from internal temperature distribution measurements
Authors: Sumi Chikayoshi , Kuwabara Jun
Published: June 2006

Although various useful techniques exist for nondestructively measuring homogeneous thermal properties, a few useful type techniques for measuring inhomogeneous thermal properties are reported such that there are many structures, materials, substances, and living things whose thermal properties cannot be measured. The temperature distribution of a target, however, can be nondestructively measured with a very high accuracy using infrared, pyroelectric, ultrasound, or magnetic resonance sensors. In this report, we describe an inverse problem technique for determining in situ the thermal conductivity distribution of a target having an arbitrary geometry using only internal steady temperature distribution measurements. The target distribution is directly determined by linearly solving heat transfer equations as the first-order partial differential equations in which temperature distributions and reference thermal conductivities of the region of interest are used as inhomogeneous coefficients. Under proper configurations of reference regions and thermal sources/sinks, this technique enables the determination of the conductivity distribution without disturbing the temperature distribution. A stable numerical solution that considers measurement noise and improper configurations of reference regions and thermal sources/sinks is also described. Technique feasibility is confirmed using two-dimensional problems through simulations and experiments using conventional infrared thermography.
Low resistance tunnel junctions with type-II heterostructures
Authors: Suzuki N. , Anan T. , Hatakeyama H. , Tsuji M.
Published: June 2006

We propose tunnel junctions with type-II heterostructures to reduce the electrical resistance of vertical-cavity surface-emitting lasers. We fabricated the type-II tunnel junctions on GaAs substrates, which consist of highly C-doped GaAsSb on the p side and highly Si-doped InGaAs on the n side. We achieved an extremely low specific resistance of 4×10−6Ωcm2, which corresponded to a resistance of 20Ω for an aperture 5μm in diameter. The specific resistance of the type-II tunnel junction was about 40% smaller than that of the type-I tunnel junction.
Interface creation and stress dynamics in plasma-deposited silicon dioxide films
Authors: Au V. , Charles C. , Boswell R. W.
Published: June 2006

The stress in amorphous silicon dioxide film grown by plasma-assisted deposition was investigated both during and after film growth for continuously and intermittently deposited films. It is shown that an intermittent deposition leads to the creation of interfacial regions during film growth, but also causes dynamical structural change in already-deposited film which results in a significantly different stress-thickness profile measured after deposition. Film growth in the continuously deposited film was also monitored using an in situ laser reflection technique, and a strong change in stress was detected at about 145nm which was attributed to the onset of island coalescence.
Integrated non-SO2 underlayer and improved line-edge-roughness dielectric etch process using 193nm bilayer resist
Authors: Bhatnagar Parijat , Panda Siddhartha , Edleman Nikki L. , Allen Scott D. , Wise Richard , Mahorowala Arpan
Published: June 2006

We present an integrated reactive ion etch (RIE) process using bilayer (a top imaging layer and a bottom underlayer) thin film imaging system to push the limits of 193nm wavelength photolithography. Minimizing the line-edge roughness (LER) and maintaining the critical dimension (CD) of the transferred pattern are important in high-resolution RIE. Along with LER and CD issues and shrinking ground rules, deleterious effects of SO2 in the underlayer etch chemistry necessitated the development of non-SO2 chemistry. Thus a N2–H2–CO chemistry was developed and integrated with the etch process of underlying borophosphosilicate glass using Ar–O2–C4F8–CO–CH3F chemistry.
Dislocations in nanocrystalline grains
Authors: Wu Xiao-Lei , Ma En
Published: June 2006

Dislocation behavior inside the very small grains of nanocrystalline metals has so far eluded high-resolution transmission electron microscopy (TEM) examinations. We have identified full dislocations using high-resolution TEM, and the different ways they reside in the 20–30nm Ni grains. The thermally activated propagation of dislocations, their interactions with twin/grain boundaries and dislocation loops, as well as their storage in nanocrystalline grains are demonstrated and discussed.
Fuel gas production by microwave plasma in liquid
Authors: Nomura Shinfuku , Toyota Hiromichi , Tawara Michinaga , Yamashita Hiroshi , Matsumoto Kenya
Published: June 2006

We propose to apply plasma in liquid to replace gas-phase plasma because we expect much higher reaction rates for the chemical deposition of plasma in liquid than for chemical vapor deposition. A reactor for producing microwave plasma in a liquid could produce plasma in hydrocarbon liquids and waste oils. Generated gases consist of up to 81% hydrogen by volume. We confirmed that fuel gases such as methane and ethylene can be produced by microwave plasma in liquid.
Silicon nanocrystals with ensemble quantum yields exceeding 60%
Authors: Jurbergs David , Rogojina Elena , Mangolini Lorenzo , Kortshagen Uwe
Published: June 2006

Silicon nanocrystals with diameters of less than 5nm show efficient photoluminescence at room temperature. For ensembles of silicon quantum dots, previous reports of photoluminescence quantum yields have usually been in the few percent range, and generally less than 30%. Here we report the plasma synthesis of silicon quantum dots and their subsequent wet-chemical surface passivation with organic ligands under strict exclusion of oxygen. Photoluminescence quantum yields exceeding 60% have been achieved at peak wavelengths of about 789nm.
Dust-acoustic solitary waves in an inhomogeneous magnetized hot dusty plasma with dust charge fluctuations
Authors: Misra Amar P. , Chowdhury A. Roy
Published: June 2006

Using a standard reductive perturbation theory, a Zakharov-Kuznnetsov (ZK) equation is derived in an inhomogeneous dusty plasma comprised of negatively charged dust grains of equal radii, Boltzmann distributed electrons and positive ions. The effects of dust thermal pressure, dust charge variation, dust-neutral collision, and the external magnetic field are taken into account. Either compressive or rarefective solitons are shown to exist depending on the critical value of the phase velocity which in turn, depends on the dust temperature and pressure. An analytic soliton solution is obtained and discussed. The behaviors of the soliton amplitude, width, and the Mach number are investigated numerically for different plasma parameters.
Drastic improvement of surface structure and current-carrying ability in YBa2Cu3O7 films by introducing multilayered structure
Authors: Pan Alexey V. , Pysarenko Serhiy , Dou Shi X.
Published: June 2006

Much smoother surfaces and significantly improved superconducting properties of relatively thick YBa2Cu3O7 (YBCO) films have been achieved by introducing a multilayered structure with alternating main YBCO and additional NdBCO layers. The surface of thick (1μm) multilayers has almost no holes compared to YBCO films. Critical current density (Jc) has been drastically increased up to a factor >3 in 1μm multilayered structures compared to YBCO films over entire temperature and applied magnetic field range. Moreover, Jc values measured in thick multilayers are even larger than in much thinner YBCO films. The Jc and surface improvement have been analyzed and attributed to growth conditions and corresponding structural peculiarities.
Superconductive B-doped nanocrystalline diamond thin films: Electrical transport and Raman spectra
Authors: Nesládek Miloš , Tromson Dominique , Mer Christine , Bergonzo Philippe , Hubik Pavel , Mares Jiri J.
Published: June 2006

Electrical transport properties of thin boron doped nanocrystalline diamond films with thicknesses of 60–500nm have been studied. The Raman spectra measured exhibit Fano resonances, characteristic for B concentrations close to the metal-to-insulator transition. Upon increasing the B concentration, the sp2 carbon related Raman resonances vanish. In such boron-doped nanocrystalline diamond films, a positive magnetoresistance could be observed at liquid helium temperatures. The boron doped diamond films show conductivity similar to that of B-doped epitaxial diamond without any significant contribution of the grain boundary transport, leading to the superconductive transition in nanocrystalline diamond at ∼1.66K.
Silver-halide segmented cladding fibers for the middle infrared
Authors: Millo Arnon , Naeh Itay , Lavi Yaron , Katzir Abraham
Published: June 2006

There is a wide interest in single-mode optical fibers for the middle infrared range of 3–30μm. These fibers will be useful for a variety of applications such as spatial filtering and interferometry. However, many technical and theoretical problems hindered the development of such fibers. Segmented cladding fibers may make it possible to combine an extremely large core area and single mode operation over a large spectral range. The design parameters may accurately control the optical properties of such fibers. We report here the design and fabrication of segmented cladding fibers made of crystalline silver halides, which are highly transparent in the middle infrared.
Enhanced electron field emission from oriented columnar AlN and mechanism
Authors: Huang A. P. , Chu Paul K. , Wu X. L.
Published: June 2006

(002) oriented AlN thin films with a columnar microstructure fabricated by vapor phase deposition with a sample bias exhibit excellent field emission properties. The field emission current density increases with smaller film thickness, and at a thickness of 400nm, the current density reaches 9.9μA∕cm2 and the turn-on field is close to 5V∕μm. Atomic force microscopy discloses nanoscale protrusions on the surface that greatly expand the emission area and efficiency. The Fowler-Nordheim plot reveals a linear dependence under low electric field (<17V∕μm), suggesting that the emission current originates from the quantum tunneling effect.
Anisotropic field effect mobility in single crystal pentacene
Authors: Lee J. Y. , Roth S. , Park Y. W.
Published: June 2006

Fan-shaped electrodes were designed on Si∕SiO2 substrate to measure the anisotropic field effect mobility in freestanding single crystal pentacene. Field effect transistor was fabricated by placing single crystal pentacene on the prepatterned electrodes. The contact between the electrodes and single crystal pentacene was enhanced by applying pressure. Angle dependence of field effect mobility in single crystal pentacene showed remarkably anisotropic behavior. The highest mobility value was estimated to be ∼2.3cm2∕Vs at room temperature.
Structural basis for tetraspanin functions as revealed by the cryo-EM structure of uroplakin complexes at 6-Å resolution
Authors: Min Guangwei , Wang Huaibin , Sun Tung-Tien , Kong Xiang-Peng
Published: June 2006

Tetraspanin uroplakins (UPs) Ia and Ib, together with their single-spanning transmembrane protein partners UP II and IIIa, form a unique crystalline 2D array of 16-nm particles covering almost the entire urothelial surface. A 6 Å–resolution cryo-EM structure of the UP particle revealed that the UP tetraspanins have a rod-shaped structure consisting of four closely packed transmembrane helices that extend into the extracellular loops, capped by a disulfide-stabilized head domain. The UP tetraspanins form the primary complexes with their partners through tight interactions of the transmembrane domains as well as the extracellular domains, so that the head domains of their tall partners can bridge each other at the top of the heterotetramer. The secondary interactions between the primary complexes and the tertiary interaction between the 16-nm particles contribute to the formation of the UP tetraspanin network. The rod-shaped tetraspanin structure allows it to serve as stable pilings in the lipid sea, ideal for docking partner proteins to form structural/signaling networks.
Structural role of Sfi1p–centrin filaments in budding yeast spindle pole body duplication
Authors: Li Sam , Sandercock Alan M. , Conduit Paul , Robinson Carol V. , Williams Roger L. , Kilmartin John V.
Published: June 2006

Centrins are calmodulin-like proteins present in centrosomes and yeast spindle pole bodies (SPBs) and have essential functions in their duplication. The Saccharomyces cerevisiae centrin, Cdc31p, binds Sfi1p on multiple conserved repeats; both proteins localize to the SPB half-bridge, where the new SPB is assembled. The crystal structures of Sfi1p–centrin complexes containing several repeats show Sfi1p as an α helix with centrins wrapped around each repeat and similar centrin–centrin contacts between each repeat. Electron microscopy (EM) shadowing of an Sfi1p–centrin complex with 15 Sfi1 repeats and 15 centrins bound showed filaments 60 nm long, compatible with all the Sfi1 repeats as a continuous α helix. Immuno-EM localization of the Sfi1p N and C termini showed Sfi1p–centrin filaments spanning the length of the half-bridge with the Sfi1p N terminus at the SPB. This suggests a model for SPB duplication where the half-bridge doubles in length by association of the Sfi1p C termini, thereby providing a new Sfi1p N terminus to initiate SPB assembly.
Reproductive migrations of the sex role reversed pipefish Nerophis lumbriciformis(Pisces; Syngnathidae)
Authors: Monteiro N. M. , Berglund A. , Vieira M. N. , Almada V. C.
Published: June 2006

Using an individual identification technique, a population of worm pipefish Nerophis lumbriciformis was followed during 19 months, in order to determine the exact use of the intertidal and, considering the specific movement patterns of males and females, the mating system exhibited by this population. Field observations showed that the number of adults increased during the breeding season, with males arriving 1 month earlier than females. Furthermore, males and females presented distinct permanence periods, showing that the intertidal is used as a mating arena. It was also observed that both male and female worm pipefish mated repeatedly over the span of a reproductive season, but females exhibited shorter remating intervals. Also, females stayed for longer periods on the mating grounds, the intertidal zone, whereas males typically left for the subtidal after mating, usually returning within 2 months. These inter‐sexual differences in the occupation of the intertidal suggest that females breed with different males but also that males accept eggs from various females since, on their return, a new group of mating partners was now available. Thus, N. lumbriciformis might be considered polygynandric. It is a clearly dimorphic species in spite of the observed polygynandry, suggesting that differences in remating intervals may be influential in determining the strength of sexual selection along with what may be expected from the polygynandrous mating system alone.