bluuebunny/crossref_metadata_2025 huggingface dataset:
Morton Effect Cyclic Vibration Amplitude Determination for Tilt Pad Bearing Supported Machinery
Authors: Lee Jung Gu , Palazzolo Alan
Published: December 2012

This paper presents theoretical models and simulation results for the synchronous, thermal transient, instability phenomenon known as the Morton effect. A transient analysis of the rotor supported by tilting pad journal bearing is performed to obtain the transient asymmetric temperature distribution of the journal by solving the variable viscosity Reynolds equation, a 2D energy equation, the heat conduction equation, and the equations of motion for the rotor. The asymmetric temperature causes the rotor to bow at the journal, inducing a mass imbalance of overhung components such as impellers, which changes the synchronous vibrations and the journal's asymmetric temperature. Modeling and simulation of the cyclic amplitude, synchronous vibration due to the Morton effect for tilting pad bearing supported machinery is the subject of this paper. The tilting pad bearing model is general and nonlinear, and thermal modes and staggered integration approaches are utilized in order to reduce computation time. The simulation results indicate that the temperature of the journal varies sinusoidally along the circumferential direction and linearly across the diameter. The vibration amplitude is demonstrated to vary slowly with time due to the transient asymmetric heating of the shaft. The approach's novelty is the determination of the large motion, cyclic synchronous amplitude behavior shown by experimental results in the literature, unlike other approaches that treat the phenomenon as a linear instability. The approach is benchmarked against the experiment of de Jongh.
Fundamental Study of Spray and Partially Premixed Combustion of Methane/Air Mixture
Authors: Askari Omid , Metghalchi Hameed , Kazemzadeh Hannani Siamak , Moghaddas Ali , Ebrahimi Reza , Hemmati Hadis
Published: December 2012

This study presents fundamentals of spray and partially premixed combustion characteristics of directly injected methane in a constant volume combustion chamber (CVCC). The constant volume vessel is a cylinder with inside diameter of 135 mm and inside height of 135 mm. Two end of the vessel are equipped with optical windows. A high speed complementary metal oxide semiconductor (CMOS) camera capable of capturing pictures up to 40,000 frames per second is used to observe flow conditions inside the chamber. The injected fuel jet generates turbulence in the vessel and forms a turbulent heterogeneous fuel–air mixture in the vessel, similar to that in a compressed natural gas (CNG) direct-injection (DI) engine. The fuel–air mixture is ignited by centrally located electrodes at a given spark delay timing of 1, 40, 75, and 110 ms. In addition to the four delay times, a 5 min waiting period was used in order to make sure of having laminar homogeneous combustion. Spray development and characterization including spray tip penetration (STP), spray cone angle (SCA), and overall equivalence ratio were investigated under 30–90 bar fuel pressures and 1–5 bar chamber pressure. Flame propagation images and combustion characteristics were determined via pressure-derived parameters and analyzed at a fuel pressure of 90 bar and a chamber pressure of 1 bar at different stratification ratios (S.R.) (from 0% to 100%) at overall equivalence ratios of 0.6, 0.8, and 1.0. Shorter combustion duration and higher combustion pressure were observed in direct injection-type combustion at all fuel air equivalence ratios compared to those of homogeneous combustion.
A Stochastic Upscaling Analysis for Carbonate Media
Authors: Yao Jun , Wang Chenchen , Yang Yongfei , Yan Xia
Published: December 2012

Carbonate rocks have well-developed macropore and micropore systems, it is necessary to study the dual pore characteristics in carbonate rocks. In this paper, based on the original macropore network and micropore network, a stochastic upscaling method is used to build the dual pore network with the integration of macropores and micropores properties in carbonates together and upscale the dual pore network to a larger scale. This method is verified by geometry-topology and flow parameters comparison, which provides an important tool to microscopic flow research in carbonate media.
Simple Recipe for Accurate Solution of Fractional Order Equations
Authors: Das Sambit , Chatterjee Anindya
Published: December 2012

Fractional order integrodifferential equations cannot be directly solved like ordinary differential equations. Numerical methods for such equations have additional algorithmic complexities. We present a particularly simple recipe for solving such equations using a Galerkin scheme developed in prior work. In particular, matrices needed for that method have here been precisely evaluated in closed form using special functions, and a small Matlab program is provided for the same. For equations where the highest order of the derivative is fractional, differential algebraic equations arise; however, it is demonstrated that there is a simple regularization scheme that works for these systems, such that accurate solutions can be easily obtained using standard solvers for stiff differential equations. Finally, the role of nonzero initial conditions is discussed in the context of the present approximation method.
On Fluid Compressibility in Switch-Mode Hydraulic Circuits—Part I: Modeling and Analysis
Authors: Van de Ven James D.
Published: December 2012

Fluid compressibility has a major influence on the efficiency of switch-mode hydraulic circuits due to the release of energy stored in fluid compression during each switching cycle and the increased flow rate through the high-speed valve during transition events. Multiple models existing in the literature for fluid bulk modulus, the inverse of the compressibility, are reviewed and compared with regards to their applicability to a switch-mode circuit. In this work, a computational model is constructed of the primary energy losses in a generic switch-mode hydraulic circuit with emphasis on losses created by fluid compressibility. The model is used in a computational experiment where the system pressure, switched volume, and fraction of air entrained in the hydraulic fluid are varied through multiple levels. The computational experiments resulted in switch-mode circuit volumetric efficiencies that ranged from 51% to 95%. The dominant energy loss is due to throttling through the ports of the high-speed valve during valve transition events. The throttling losses increase with the fraction of entrained air and the volume of fluid experiencing pressure fluctuations, with a smaller overall influence seen as a result of the system pressure. The results of the computational experiment indicate that to achieve high efficiency in switch-mode hydraulic circuits, it is critical to minimize both the entrained air in the hydraulic fluid and the fluid volume between the high-speed valve and the pump, motor, or actuator. These computational results are compared with experimental results in Part II of this two part paper series.
Quantitative Compressibility Effects in Thermal Elastohydrodynamic Circular Contacts
Authors: Habchi W. , Bair S.
Published: December 2012

This paper investigates the effects of lubricant compressibility on the film-forming performance of thermal elastohydrodynamic lubricated (EHL) circular contacts. Numerical film thickness predictions using the classical Dowson and Higginson relationship are compared to those that would be obtained using a more realistic compressibility model, all other parameters kept unchanged. This allows an isolation of the realistic compressibility effects on the film-forming performance. For realistic predictions, the authors consider two model liquids from the 1953 report of the ASME Research Committee on Lubrication, the most and the least compressible. The compressibility of these liquids is modeled using the Tait equation of state (EoS) while all other transport properties are kept unchanged for the sake of isolating compressibility effects. In addition, the same typical generalized-Newtonian behavior is assumed for both model liquids. The results reconfirm the well-known observations that minimum film thickness is very little affected by lubricant compressibility while central film thickness decreases linearly with the increase in volume compression of the lubricant. It is also observed that the relative errors on central film thicknesses induced by the use of the Dowson and Higginson relationship for compressibility increase with load and temperature and are very little affected by mean entrainment speed. Compressibility is shown to be a significant source of error in film-derived measurements of pressure-viscosity coefficients especially at high temperature. The thermodynamic scaling that provides an accurate and consistent framework for the correlation of the thermophysical properties of liquids with temperature and pressure requires an accurate equation of state. In brief, this paper highlights the importance of using realistic transport properties modeling based on thermodynamic scaling for an accurate numerical prediction of the performance of EHL contacts.
Tungstate formation in a model scandate thermionic cathode
Authors: Wan Congshang , Kordesch Martin E.
Published: December 2012

Crystalline compounds found at the surface of model Ba-Sc-O-W thermionic cathodes (“scandate”) are uniquely identified using Raman spectroscopy. Thin films of sputtered BaO and Sc2O3 on W have been observed in thermionic emission microscopy, field emission scanning electron microscopy, optical microscopy, and Raman Spectroscopy. While the best thermionic electron emission is observed from areas that at the end of the cathode life are completely devoid of thin film BaO, Sc2O3 or observable bulk oxide or tungstate material, the poor emission areas are characterized by BaWO4, Ba2WO5 and long chain linear tungstates (νas = 860 cm−1) that are related to Scx-WOy components. There is no evidence from Raman spectroscopy that tetrahedral Sc2(WO4)3 is present or forms on the surface of the model cathode, or for the presence of Ba3WO6.
Atomic layer deposition of cobalt oxide thin films using cyclopentadienylcobalt dicarbonyl and ozone at low temperatures
Authors: Han Byeol , Ha Choi Kyu , Min Park Jae , Woo Park Jung , Jung Jongwan , Lee Won-Jun
Published: December 2012

The authors report the atomic layer deposition (ALD) of cobalt oxide thin films at 50–150 °C using alternating exposures to cyclopentadienylcobalt dicarbony [CpCo(CO)2] and ozone. The growth rates were 0.08–0.11 nm/cycle and the ALD cobalt oxide films showed excellent step coverage. With increasing substrate temperature to 200 °C, however, the growth rate sharply increased and cobalt-rich film was deposited owing to thermal decomposition of the cobalt precursor. The reaction of the cobalt precursor molecule with the growing film surface was investigated by in situ quartz crystal microbalance (QCM), and the QCM result also indicates that CpCo(CO)2 thermally decomposes to cobalt on the growth surface at 200 °C.
X-ray photoelectron spectroscopic study on interface bonding between Pt and Zn- and O-terminated ZnO
Authors: Yoshitake Michiko , Blumentrit Petr , Nemsak Slavomir
Published: December 2012

Interface bonding between Pt and Zn- and O-terminated ZnO surfaces was investigated by precise analysis of x-ray photoelectron spectra. The interfaces were formed by vapor depositing Pt onto the ZnO surfaces in ultrahigh vacuum. The changes in the Zn 2p3/2, O 1s, Zn LMM Auger, and Pt 4f7/2 spectra upon Pt deposition were observed. The changes in the shape of the Zn LMM spectra and the shifts in the binding energy of Zn 2p3/2 and O 1s revealed that there was a metallic Zn component in the Zn LMM and Zn 2p3/2 spectra for Zn-terminated ZnO and a Pt-O component in the O 1s spectra for both Zn- and O-terminated ZnO. Peaks were fitted with multiple components accordingly. The binding energy shifts of Zn 2p3/2 and O 1s for the ZnO component were almost the same, which confirmed that the fitting was reasonable. From the fitting results, the interface bonding was concluded to be O-terminated, i.e., Zn-O-Pt bond formation occurred at the interface for both Zn- and O-terminated ZnO. This clearly demonstrated that the stable interface bonding occurring between Pt and ZnO is Zn-O-Pt bonding whether the ZnO substrate is initially Zn-terminated or O-terminated.
Photoluminescence characterization of polythiophene films incorporated with highly functional molecules such as metallophthalocyanine
Authors: Kobe Hiroaki , Ohnaka Kazumasa , Kato Hitoshi , Takemura Susumu , Shimada Kazuhiro , Hiramatsu Tomoyasu , Matsui Kazunori
Published: December 2012

The photoluminescence (PL) of conducting polymer polythiophene (PT) films incorporated with metallophthalocyanines (PcMs) such as CuPc, MgPc, FePc, Li2Pc, and CoPc was studied by PL and time-correlated single photon counting (TCSPC) measurements. Polymer films were prepared by electrochemical polymerization and PcMs migrated into the polymer films by a diffusion method using acetonitrile or toluene as a solvent to dissolve the PcMs. The wavelength of PL emission peaks changed significantly depending on the solvent used in the doping process. Using acetonitrile, the observed PL emission peaks originated from the Q band, whereas they were assigned to the Soret band in the case of toluene. TCSPC measurements showed that PL emission took place through a ligand–ligand transition process when using acetonitrile because the average lifetimes were comparable and independent of the central metal ions for CoPc-, Li2Pc-, and MgPc-doped polymer films. Conversely, using toluene, it was found that ligand–ligand emission occurred for Li2Pc-, MgPc-, and FePc-doped films. To identify the cause of the drastic change in PL emission pattern, x-ray photoelectron spectroscopy measurements were obtained. A lower binding energy component appeared in the C 1s core-level spectra of acetonitrile-processed PcM-doped PT films, whereas this component shifted to higher energy and overlapped with the main peak for toluene-processed PcM-doped PT films. The lower binding energy component corresponded to photoelectrons due to the C atoms in the benzene rings of the ligand. Lower binding energy components also appeared in the N 1s core-level spectra of acetonitrile-processed PcM-doped PT films, and this component shifted to higher energy for toluene-processed PcM-doped PT films. These lower energy components were assigned to the core-level peaks due to the N atoms at the meso position bridging between pyrrole rings. This suggests that the electron charge at the N sites of the meso positions in toluene-processed films was smaller than in acetonitrile-processed ones. The changes in energy at benzene C sites and meso N sites suggest that the electronic states of the phthalocyanine in the toluene-processed films were porphyrin-like, so the Soret band became dominant in the PL emission spectrum.
A similarity study of content‐based image retrieval system for breast cancer using decision tree
Authors: Cho Hyun‐chong , Hadjiiski Lubomir , Sahiner Berkman , Chan Heang‐Ping , Helvie Mark , Paramagul Chintana , Nees Alexis V.
Published: December 2012

Purpose:

We are developing a decision tree content‐based image retrieval (DTCBIR) CADx system to assist radiologists in characterization of breast masses on ultrasound images.

Methods:

Three DTCBIR configurations, including decision tree with boosting (DTb), decision tree with full leaf features (DTL), and decision tree with selected leaf features (DTLs) were compared. For DTb, features of a query mass were combined first into a merged feature score and then masses with similar scores were retrieved. For DTL and DTLs, similar masses were retrieved based on the Euclidean distance between feature vectors of the query and those of selected references. For each DTCBIR configuration, we investigated the use of full feature set and subset of features selected by the stepwise linear discriminant analysis (LDA) and simplex optimization method, resulting in six retrieval methods and selected five, DTb‐lda, DTL‐lda, DTb‐full, DTL‐full, and DTLs‐full, for the observer study. Three MQSA radiologists rated similarities between the query mass and computer‐retrieved three most similar masses using nine‐point similarity scale (9 = very similar).

Results:

For DTb‐lda, DTL‐lda, DTb‐full, DTL‐full, and DTLs‐full, averageAz values were 0.90 ± 0.03, 0.85 ± 0.04, 0.87 ± 0.04, 0.79 ± 0.05, and 0.71 ± 0.06, respectively, and average similarity ratings were 5.00, 5.41, 4.96, 5.33, and 5.13, respectively.

Conclusions:

The DTL‐lda is a promising DTCBIR CADx configuration which had simple tree structure, good classification performance, and highest similarity rating.
Evaluation of superficial dosimetry between treatment planning system and measurement for several breast cancer treatment techniques
Authors: Akino Yuichi , Das Indra J. , Bartlett Gregory K. , Zhang Hualin , Thompson Elizabeth , Zook Jennifer E.
Published: December 2012

Purpose:

Dosimetric accuracy in radiation treatment of breast cancer is critical for the evaluation of cosmetic outcomes and survival. It is often considered that treatment planning systems (TPS) may not be able to provide accurate dosimetry in the buildup region. This was investigated in various treatment techniques such as tangential wedges, field‐in‐field (FF), electronic compensator (eComp), and intensity‐modulated radiotherapy (IMRT).

Methods:

Under Institutional Review Board (IRB) exemption, radiotherapy treatment plans of 111 cases were retrospectively analyzed. The distance between skin surface and 95% isodose line was measured. For measurements, Gafchromic EBT2 films were used on a humanoid unsliced phantom. Multiple layers of variable thickness of superflab bolus were placed on the breast phantom and CT scanned for planning. Treatment plans were generated using four techniques with two different grid sizes (1 × 1 and 2.5 × 2.5 mm2) to provide optimum dose distribution. Films were placed at different depths and exposed with the selected techniques. A calibration curve for dose versus pixel values was also generated on the same day as the phantom measurement was conducted. The DICOM RT image, dose, and plan data were imported to the in‐house software. On axial plane of CT slices, curves were drawn at the position where EBT2 films were placed, and the dose profiles on the lines were acquired. The calculated and measured dose profiles were separated by check points which were marked on the films before irradiation. The segments of calculated profiles were stretched to match their resolutions to that of film dosimetry.

Results:

On review of treatment plans, the distance between skin and 95% prescribed dose was up to 8 mm for plans of 27 patients. The film measurement revealed that the medial region of phantom surface received a mere 45%–50% of prescribed dose. For wedges, FF, and eComp techniques, region around the nipple received approximately 80% of prescribed dose, although only IMRT showed inhomogeneous dose profile. At deeper depths mainly (6–11 mm depths), film dosimetry showed good agreement with the TPS calculation. In contrast, the measured dose at a 3‐mm depth was higher than TPS calculation by 15%–30% for all techniques. For the tangential and IMRT techniques, 1 × 1 mm2 grid size showed a smaller difference than that with a 2.5 × 2.5 mm2 grid size compared to the measurements.

Conclusions:

In general, TPS even with advanced algorithms do not provide accurate dosimetry in the buildup region, as verified by EBT2 film for all treatment techniques. For all cases, TPS and measured doses were in agreement from 6 mm in depth but differed at shallower depths. Grid size plays an important role in dose calculation. For accurate dosimetry small grid size should be used where differences are lower between TPS and measurements.
Using the Xbox Kinect sensor for positional data acquisition
Authors: Ballester Jorge , Pheatt Chuck
Published: December 2012

The Kinect sensor was introduced in November 2010 by Microsoft for the Xbox 360 video game system. It is designed to be positioned above or below a video display to track player body and hand movements in three dimensions (3D). The sensor contains a red, green, and blue (RGB) camera, a depth sensor, an infrared (IR) light source, a three-axis accelerometer, and a multi-array microphone, as well as hardware required to transmit sensor information to an external receiver. In this article, we evaluate the capabilities of the Kinect sensor as a 3D data-acquisition platform for use in physics experiments. Data obtained for a simple pendulum, a spherical pendulum, projectile motion, and a bouncing basketball are presented. Overall, the Kinect sensor is found to be a useful data-acquisition tool for motion studies in the physics laboratory.
Solution of the quantum initial value problem with transparent boundary conditions
Authors: Puga A. , Miller B. N.
Published: December 2012

Many systems of interest at the forefront of technological development, for example, in quantum computation, consist of weakly interacting elements that obey quantum mechanics. A challenge for modern theoretical physics is to develop a systematic methodology for approaching these “open” quantum systems. In particular, applied mathematicians have formulated the method of transparent boundary conditions (TBCs) to model interacting quantum systems of infinite extent. Here, we consider a particular application of TBCs to the escape of a particle from a one-dimensional infinite well when one of the bounding barriers is extinguished. We analytically obtain the exact time-dependent wave function by a Green's function method and then show that a numerical solution based on the TBC method is in excellent agreement. This work was motivated by an experiment carried out at the University of Texas on escape from a gravitational wedge billiard. Physicists have used billiards to understand and explore both classical and quantum chaos. Although the original experiment was carried out in the classical regime, current work is probing lower temperatures, where a quantum mechanical formulation is required.
Variations on the adiabatic invariance: The Lorentz pendulum
Authors: Sánchez-Soto Luis L. , Zoido Jesús
Published: December 2012

We analyze a simple variant of the Lorentz pendulum in which the length is varied exponentially instead of uniformly as in the standard case. We establish quantitative criteria for the condition of adiabatic changes in both pendula and demonstrate their substantially different physical behavior with regard to adiabatic invariance.
Computational templates for introductory nuclear science using mathcad
Authors: Sarantites D. G. , Sobotka L. G.
Published: December 2012

Computational templates used to teach an introductory course in nuclear chemistry and physics at Washington University in St. Louis are presented in brief. The templates cover both basic and applied topics.
The process of transforming an advanced lab course: Goals, curriculum, and assessments
Authors: Zwickl Benjamin M. , Finkelstein Noah , Lewandowski H. J.
Published: December 2012

A thoughtful approach to designing and improving labs, particularly at the advanced level, is critical for the effective preparation of physics majors for professional work in industry or graduate school. With that in mind, physics education researchers in partnership with the physics faculty at the University of Colorado Boulder have overhauled the senior-level Advanced Physics Lab course. The transformation followed a three part process of establishing learning goals, designing curricula that align with the goals, and assessment. Similar efforts have been carried out in physics lecture courses at the University of Colorado Boulder, but this is the first systematic research-based revision of one of our laboratory courses. The outcomes of this effort include a set of learning goals, a suite of new lab-skill activities and transformed optics labs, and a set of assessments specifically tailored for a laboratory environment. While the particular selection of advanced lab experiments varies widely between institutions, the overall transformation process, the learning goals, and the assessments are broadly applicable to the instructional lab community.
Interdisciplinary Graduate Training in Teaching Labs
Authors: Vale Ronald D. , DeRisi Joseph , Phillips Rob , Mullins R. Dyche , Waterman Clare , Mitchison Timothy J.
Published: December 2012

Intensive, short-term courses meld students and faculty and new techniques in pursuit of genuine research questions.
Genome-Wide Detection of Single-Nucleotide and Copy-Number Variations of a Single Human Cell
Authors: Zong Chenghang , Lu Sijia , Chapman Alec R. , Xie X. Sunney
Published: December 2012

Single-Cell Sequencing

With the rapid progress in sequencing technologies, single-cell sequencing is now possible, promising insight into how cell-to-cell heterogeneity affects biological behavior. Achieving adequate genome coverage remains a challenge because single-cell sequencing relies on genome amplification that is prone to sequence bias.

Zong
et al.

(p.
1622
) report a new amplification method: multiple annealing and looping-based amplification cycles that allowed 93% genome coverage for a human cell. This coverage facilitated accurate detection of point mutations and copy number variations.

Lu
et al.

(p.
1627
) used the method to sequence 99 sperm cells from a single individual. Mapping the meiotic crossovers revealed a nonrandom distribution with a reduced recombination rate near transcription start sites.
Symmetry Meets Topology
Authors: Qi Xiao-Liang
Published: December 2012

A unified theory may describe both the persistent spin of electrons and the design of novel materials.
The Breakthroughs of 2012
Authors: Alberts Bruce
Published: December 2012

We at
Science
have once again had the challenge of choosing 10 scientific accomplishments to highlight in this final issue of the year. Our 10 choices reveal that 2012 has been a remarkable one for the physics of particles (the Higgs boson, neutrinos, and Majorana “quasiparticles”), as well as for biological discovery (the production of eggs from stem cells, the derivation of some modern human genes from Denisovan ancestors, and the greatly enhanced cataloging of human genetic regulation). Three technological breakthroughs also appear on our list: functional brain/machine interfaces, TALENS as a tool for genetic engineering, and the x-ray laser determination of a protein structure. And finally, there is one feat of physics and engineering virtuosity: the Curiosity rover's remarkably precise, gentle, “sky crane” landing on Mars.
Negevirus: a Proposed New Taxon of Insect-Specific Viruses with Wide Geographic Distribution
Authors: Vasilakis Nikos , Forrester Naomi L. , Palacios Gustavo , Nasar Farooq , Savji Nazir , Rossi Shannan L. , Guzman Hilda , Wood Thomas G. , Popov Vsevolod , Gorchakov Rodion , González Ana Vázquez , Haddow Andrew D. , Watts Douglas M. , da Rosa Amelia P. A. Travassos , Weaver Scott C. , Lipkin W. Ian , Tesh Robert B.
Published: December 2012

Six novel insect-specific viruses, isolated from mosquitoes and phlebotomine sand flies collected in Brazil, Peru, the United States, Ivory Coast, Israel, and Indonesia, are described. Their genomes consist of single-stranded, positive-sense RNAs with poly(A) tails. By electron microscopy, the virions appear as spherical particles with diameters of ∼45 to 55 nm. Based on their genome organization and phylogenetic relationship, the six viruses, designated Negev, Ngewotan, Piura, Loreto, Dezidougou, and Santana, appear to form a new taxon, tentatively designated Negevirus. Their closest but still distant relatives are citrus leposis virus C (CiLV-C) and viruses in the genusCilevirus, which are mite-transmitted plant viruses. The negeviruses replicate rapidly and to high titer (up to 1010PFU/ml) in mosquito cells, producing extensive cytopathic effect and plaques, but they do not appear to replicate in mammalian cells or mice. A discussion follows on their possible biological significance and effect on mosquito vector competence for arboviruses.
Complex Alternative Cytoplasmic Protein Isoforms of the Kaposi's Sarcoma-Associated Herpesvirus Latency-Associated Nuclear Antigen 1 Generated through Noncanonical Translation Initiation
Authors: Toptan Tuna , Fonseca Lidia , Kwun Hyun Jin , Chang Yuan , Moore Patrick S.
Published: December 2012

Kaposi's sarcoma-associated herpesvirus (KSHV) latency associated-nuclear antigen 1 (LANA1) protein is constitutively expressed in all KSHV-infected cells, as well as in all forms of KSHV-associated malignancies. LANA1 is a multifunctional KSHV oncoprotein containing multiple repeat sequences that is important for viral episome maintenance and the regulation of cellular and viral gene expression. We characterize here multiple LANA1 isoforms and show that ∼50% of LANA1 is naturally generated as N-terminally truncated shoulder proteins that are detected on SDS-PAGE as faster-migrating shoulder bands designated LANA1
S
. Higher-molecular-weight LANA1
S
isoforms initiate downstream at noncanonical sites within the N-terminal region, whereas lower-molecular-weight LANA1
S
isoforms initiate downstream within the central repeat 1 domain. LANA1
S
proteins lack an N-terminal nuclear localization signal motif, and some isoforms differ from full-length, canonical LANA1 by localizing to perinuclear and cytoplasmic sites. Although LANA1 has until now been assumed to be solely active in the nucleus, this finding indicates that this major KSHV oncoprotein may have cytoplasmic activities as well. KSHV overcomes its limited genetic coding capacity by generating alternatively initiated protein isoforms that may have distinct biological functions.
Use of FMEA analysis to reduce risk of errors in prescribing and administering drugs in paediatric wards: a quality improvement report
Authors: Lago Paola , Bizzarri Giancarlo , Scalzotto Francesca , Parpaiola Antonella , Amigoni Angela , Putoto Giovanni , Perilongo Giorgio
Published: December 2012

Objective

Administering medication to hospitalised infants and children is a complex process at high risk of error. Failure mode and effect analysis (FMEA) is a proactive tool used to analyse risks, identify failures before they happen and prioritise remedial measures. To examine the hazards associated with the process of drug delivery to children, we performed a proactive risk-assessment analysis.

Design and setting

Five multidisciplinary teams, representing different divisions of the paediatric department at Padua University Hospital, were trained to analyse the drug-delivery process, to identify possible causes of failures and their potential effects, to calculate a risk priority number (RPN) for each failure and plan changes in practices.

Primary outcome

To identify higher-priority potential failure modes as defined by RPNs and planning changes in clinical practice to reduce the risk of patients harm and improve safety in the process of medication use in children.

Results

In all, 37 higher-priority potential failure modes and 71 associated causes and effects were identified. The highest RPNs related (>48) mainly to errors in calculating drug doses and concentrations. Many of these failure modes were found in all the five units, suggesting the presence of common targets for improvement, particularly in enhancing the safety of prescription and preparation of endovenous drugs. The introductions of new activities in the revised process of administering drugs allowed reducing the high-risk failure modes of 60%.

Conclusions

FMEA is an effective proactive risk-assessment tool useful to aid multidisciplinary groups in understanding a process care and identifying errors that may occur, prioritising remedial interventions and possibly enhancing the safety of drug delivery in children.
An international measure of awareness and beliefs about cancer: development and testing of the ABC
Authors: Simon Alice E , Forbes Lindsay J L , Boniface David , Warburton Fiona , Brain Kate E , Dessaix Anita , Donnelly Michael , Haynes Kerry , Hvidberg Line , Lagerlund Magdalena , Petermann Lisa , Tishelman Carol , Vedsted Peter , Vigmostad Maria Nyre , Wardle Jane , Ramirez Amanda J
Published: December 2012

Objectives

To develop an internationally validated measure of cancer awareness and beliefs; the awareness and beliefs about cancer (ABC) measure.

Design and setting

Items modified from existing measures were assessed by a working group in six countries (Australia, Canada, Denmark, Norway, Sweden and the UK). Validation studies were completed in the UK, and cross-sectional surveys of the general population were carried out in the six participating countries.

Participants

Testing in UK English included cognitive interviewing for face validity (N=10), calculation of content validity indexes (six assessors), and assessment of test–retest reliability (N=97). Conceptual and cultural equivalence of modified (Canadian and Australian) and translated (Danish, Norwegian, Swedish and Canadian French) ABC versions were tested quantitatively for equivalence of meaning (≥4 assessors per country) and in bilingual cognitive interviews (three interviews per translation). Response patterns were assessed in surveys of adults aged 50+ years (N≥2000) in each country.

Main outcomes

Psychometric properties were evaluated through tests of validity and reliability, conceptual and cultural equivalence and systematic item analysis. Test–retest reliability used weighted-κ and intraclass correlations. Construction and validation of aggregate scores was by factor analysis for (1) beliefs about cancer outcomes, (2) beliefs about barriers to symptomatic presentation, and item summation for (3) awareness of cancer symptoms and (4) awareness of cancer risk factors.

Results

The English ABC had acceptable test–retest reliability and content validity. International assessments of equivalence identified a small number of items where wording needed adjustment. Survey response patterns showed that items performed well in terms of difficulty and discrimination across countries except for awareness of cancer outcomes in Australia. Aggregate scores had consistent factor structures across countries.

Conclusions

The ABC is a reliable and valid international measure of cancer awareness and beliefs. The methods used to validate and harmonise the ABC may serve as a methodological guide in international survey research.
Impaired insulin-stimulated glucose transport in ATM-deficient mouse skeletal muscle
Authors: Ching James Kain , Spears Larry D. , Armon Jennifer L. , Renth Allyson L. , Andrisse Stanley , Collins Roy L. , Fisher Jonathan S.
Published: December 2012

There are reports that ataxia telangiectasia mutated (ATM) plays a role in insulin-stimulated Akt phosphorylation, although this is not the case in some cell types. Because Akt plays a key role in insulin signaling, which leads to glucose transport in skeletal muscle, the predominant tissue in insulin-stimulated glucose disposal, we examined whether insulin-stimulated Akt phosphorylation and (or) glucose transport would be decreased in skeletal muscle of mice lacking functional ATM, compared with muscle from wild-type mice. We found that in vitro insulin-stimulated Akt phosphorylation was normal in soleus muscle from mice with 1 nonfunctional allele of ATM (ATM+/−) and from mice with 2 nonfunctional alleles (ATM−/−). However, insulin did not stimulate glucose transport or the phosphorylation of AS160 in ATM−/− soleus. ATM protein level was markedly higher in wild-type extensor digitorum longus (EDL) than in wild-type soleus. In EDL from ATM−/− mice, insulin did not stimulate glucose transport. However, in contrast to findings for soleus, insulin-stimulated Akt phosphorylation was blunted in ATM−/− EDL, concomitant with a tendency for insulin-stimulated phosphatidylinositol 3-kinase activity to be decreased. Together, the findings suggest that ATM plays a role in insulin-stimulated glucose transport at the level of AS160 in muscle comprised of slow and fast oxidative-glycolytic fibers (soleus) and at the level of Akt in muscle containing fast glycolytic fibers (EDL).
Synthesis of modified carbon nanotube-supported Pd and the catalytic performance for hydrodehalogenation of aryl halides
Authors: Xu Yuandong , Chen Long , Wang Xiaolai
Published: December 2012

The effects of surface functionalization on the deposition of Pd nanoparticles on multi-walled carbon nanotubes (CNTs) have been studied. Two methods were used for the functionalization of CNTs: one employed a 1:1 (v/v) mixture of concentrated H2SO4/HNO3, sonicated at RT; the other employed a 3:1 (v/v) mixture of concentrated H2SO4/HNO3, sonicated at 60 °C. A large number of surface oxide groups were introduced on the surface of functionalized CNTs, especially in strong oxidation power (H2SO4/HNO3 = 3:1, 60 °C). The dispersion of Pd nanoparticles on CNTs was found to depend on the amount of surface oxide groups, with larger amounts of surface oxide groups resulting in higher dispersion of Pd nanoparticles. The effects of CNT surface functionalization on the performance of Pd/CNTs catalysts were studied, and the reaction conditions optimized, using the hydrodebromination of bromobenzene as model reaction. Under optimal conditions, the hydrodehalogenation of various aryl halides were tested over Pd/CNTs catalysts.
Divergent life-history races do not represent Chinook salmon coast-wide: the importance of scale in Quaternary biogeography
Authors: Moran Paul , Teel David J. , Banks Michael A. , Beacham Terry D. , Bellinger M. Renee , Blankenship Scott M. , Candy John R. , Garza John Carlos , Hess Jon E. , Narum Shawn R. , Seeb Lisa W. , Templin William D. , Wallace Colin G. , Smith Christian T.
Published: December 2012

The dynamic Quaternary geology of the Pacific Ring of Fire created substantial challenges for biogeography. Fish life history and population genetic variation were shaped by climate change, repeated formation and subsidence of ice sheets, sea-level change, volcanism and tectonics, isostatic rebound, and now human activities. It is widely recognized in Chinook salmon (Oncorhynchus tshawytscha) that parallel evolution and phenotypic plasticity have obscured range-wide patterns of life-history segregation with evolutionary lineage, yet the idea of the lineages themselves persists. We employed a large, internationally standardized, microsatellite data set to explore population structure at coast-wide scale and test for two divergent lineages, whether or not related to life history. We found at least 27 distinct lineages. However, relationships among groups were poorly resolved — essentially a star phylogeny. We found pervasive isolation by distance among groups, complicating cluster analysis. Only in the interior Columbia River (east of the Cascade Mountains) is there a deep genetic bifurcation that supports both the two-lineage hypothesis and the life-history segregation hypothesis. This broad-scale perspective helps reconcile different views of Chinook salmon phylogeography and life-history distribution.
LESSONS FROM OXYPNICTIDE THIN FILMS
Authors: HAINDL SILVIA , KIDSZUN MARTIN , ONKEN FRANZISKA , MIETKE ALEXANDER , THERSLEFF THOMAS
Published: December 2012

First experiments on the growth of oxypnictide F-doped LaFeAsO thin films indicated an incomplete normal-to-superconducting transition and offered a work programme challenging to overcome possible difficulties in their fabrication. In this regard the possibility of an all in-situ epitaxial growth appeared to be a matter of time and growth parameters. The following review clarifies that F-doped oxypnictide thin films are extremely difficult to grow by in-situ PLD due to the formation of very stable impurity phases such as oxyfluorides (LaOF) and oxides ( La2O3) and the loss of stoichiometry possibly due to incongruent evaporation of the target or re-evaporation of volatile elements at the substrate surface. However, the review also demonstrates that the employed two-step fabrication process for oxypnictide thin films has been successfully applied in the preparation of clean polycrystalline as well as of epitaxial thin films. Fundamental investigations on the upper critical field, its temperature dependence and its anisotropy contributed to an understanding of multiband superconductivity in oxypnictides.
COMBINATION OF MULTIPLE FEATURE SELECTION METHODS FOR TEXT CATEGORIZATION BY USING COMBINATORIAL FUSION ANALYSIS AND RANK-SCORE CHARACTERISTIC
Authors: LI YANJUN , HSU D. FRANK , CHUNG SOON M.
Published: December 2012

Effective feature selection methods are important for improving the efficiency and accuracy of text categorization algorithms by removing redundant and irrelevant terms from the corpus. Extensive research has been done to improve the performance of individual feature selection methods. However, it is always a challenge to come up with an individual feature selection method which would outperform other methods in most cases. In this paper, we explore the possibility of improving the overall performance by combining multiple individual feature selection methods. In particular, we propose a method of combining multiple feature selection methods by using an information fusion paradigm, called Combinatorial Fusion Analysis (CFA). A rank-score function and its associated graph, called rank-score graph, are adopted to measure the diversity of different feature selection methods. Our experimental results demonstrated that a combination of multiple feature selection methods can outperform a single method only if each individual feature selection method has unique scoring behavior and relatively high performance. Moreover, it is shown that the rank-score function and rank-score graph are useful for the selection of a combination of feature selection methods.
MODELING WORDNET GLOSSES TO PERFORM WORD SENSE DISAMBIGUATION
Authors: FRAGOS KOSTAS
Published: December 2012

In this work, we propose a new measure of semantic relatedness between concepts applied in word sense disambiguation. Using the overlaps between WordNet definitions of concepts (glosses) and the so-called goodness of fit statistical test we establish a formal mechanism for quantifying and estimating the semantic relatedness between concepts. More concretely, we model WordNet glosses overlaps by making a theoretical assumption about their distribution and then we quantify the discrepancy between the theoretical and actual distribution. This discrepancy is suitably used to measure the relatedness between the input concepts. The experimental results showed very good performance on SensEval-2 lexical sample data for word sense disambiguation.
IMAGE PYRAMIDS FOR CALCULATION OF THE BOX COUNTING DIMENSION
Authors: AHAMMER H. , MAYRHOFER-REINHARTSHUBER M.
Published: December 2012

The fractal dimensions of real world objects are commonly investigated using digital images. Unfortunately, these images are unable to represent an infinitesimal range of scales. In addition, a proper evaluation of the applied methods that encompass the image processing techniques is often missing. Several mathematical well-defined fractals with theoretically known fractal dimensions, represented by digital images, were investigated in this work. The very popular Box counting method was compared to a new image pyramid approach as well as to the Minkowski dilation method. Effects from noise and altered aspect ratios were also considered. The new Pyramid method is quite identical to the Box counting method, but it is easier to implement. Additionally, the calculation times are much shorter and memory requirements are almost comparable.
TEXT-INDEPENDENT VOICE CONVERSION BASED ON CHINESE PHONEME CLASSIFICATION AND KERNEL EIGENVOICES GAUSSIAN MIXTURE MODEL
Authors: LI YANPING , ZHANG LINGHUA , DING HUI
Published: December 2012

This paper proposed a novel algorithm for text-independent voice conversion based on Chinese phoneme classification and kernel eigenvoices Gaussian mixture model. The phoneme classification can avoid the disturbance of linguistic information and spectral smoothing. A speaker adaptation technique of kernel eigenvoices was employed for performing spectral conversion between speakers for each category phoneme, adapting the conversion parameters derived for the pre-stored pairs of speakers to a desired pair, which can relax the parallel constraint effectively. Objective test on the spectral conversion accuracy demonstrated that the proposed kernel algorithm can effectively exploit the nonlinearity in supervector space. In subjective listening test, an ABX test was performed and the proposed algorithm was preferred to the existing eigenvoice algorithm by 4.75%, and improved quality by 10.91% in terms of mean opinion score (MOS). Both objective and subjective tests demonstrated that the proposed algorithm effectively enhanced speech quality and speaker individuality in a text-independent manner.
Real-time determination of sarcomere length of a single cardiomyocyte during contraction
Authors: Peterson Pearu , Kalda Mari , Vendelin Marko
Published: December 2012

Sarcomere length of a cardiomyocyte is an important control parameter for physiology studies on a single cell level; for instance, its accurate determination in real time is essential for performing single cardiomyocyte contraction experiments. The aim of this work is to develop an efficient and accurate method for estimating a mean sarcomere length of a contracting cardiomyocyte using microscopy images as an input. The novelty in developed method lies in 1) using unbiased measure of similarities to eliminate systematic errors from conventional autocorrelation function (ACF)-based methods when applied to region of interest of an image, 2) using a semianalytical, seminumerical approach for evaluating the similarity measure to take into account spatial dependence of neighboring image pixels, and 3) using a detrend algorithm to extract the sarcomere striation pattern content from the microscopy images. The developed sarcomere length estimation procedure has superior computational efficiency and estimation accuracy compared with the conventional ACF and spectral analysis-based methods using fast Fourier transform. As shown by analyzing synthetic images with the known periodicity, the estimates obtained by the developed method are more accurate at the subpixel level than ones obtained using ACF analysis. When applied in practice on rat cardiomyocytes, our method was found to be robust to the choice of the region of interest that may 1) include projections of carbon fibers and nucleus, 2) have uneven background, and 3) be slightly disoriented with respect to average direction of sarcomere striation pattern. The developed method is implemented in open-source software.