bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of the French Reactor Pressure Vessel Integrity in PTS Conditions. Thermalhydraulic and Thermomechanical Studies of the Small Break LOCA in a Three Loop PWR Plant
Authors: Martin A. , Bugat S. , Ternon Morin F. , Bellet S. , Bezdikian G.
Published: July 2013

This paper deals with the Research and Development program started by E.D.F. about the study and risk characterization of a PWR vessel (RPV) submitted to a Pressurized Thermal Shock (PTS). The PTS is described by simulation with the thermalhydraulic Finite Element (FE) code N3S coupled with the thermal-solid code SYRTHES to take into account the conjugate heat transfer on the cooling of the vessel. The geometry used represents a three loop PWR plant which is the more common running plant in the world. In this study, the simulated finite element mesh takes into account as much as possible the actual geometry of the lower plenum such as its columns and plates instrumentation. The configuration investigated is related to the injection of cold water in the vessel during a penalizing operating transients and its impact on the solid part formed by cladding and base metal. Numerical results are given in terms of temperature field in the cold legs and in the downcomer. The obtained numerical description of the transient (internal pressure and temperature field within the vessel) is used as boundary conditions for a full mechanical computation of the stresses. This thermal–mechanical transient is obtained by F.E. simulation using the F.E. code Code_Aster on a 3D mesh of the vessel, covering the two core–shells and their circumferential welds, as well as the internal cladding. Based on an analytical method specially established for underclad flaws, the corrected elastic stress intensity factor Kβ during the transient is evaluated for an hypothetical flaw, by extracting the stresses along a radial segment. The severity of the flaw with respect to the transient is quantified by the minimum of the ratio KIc/Kβ, where KIc refers to the base metal fracture toughness for brittle initiation. The evolution of the severity with the position of the hypothetical flaw is studied and compared with the results given by the classical uni–dimensional method. The results show that such a complete thermal–hydraulic and mechanic 3–dimensional analysis allows to reduce considerably the severity of the flaws, thus improving the margins regarding brittle fracture.
Distributions of Fabrication Flaws in Reactor Pressure Vessels for Structural Integrity Evaluations
Authors: Simonen F. A. , Schuster G. J. , Doctor S. R. , Dickson T. L.
Published: July 2013

To reduce uncertainties in flaw-related inputs for probabilistic fracture mechanics (PFM) evaluations, the U.S. Nuclear Regulatory Commission (USNRC) has supported research at Pacific Northwest National Laboratory (PNNL) involving nondestructive and destructive examinations for fabrication flaws in reactor pressure vessel (RPV) material. Using these data, statistical distributions have been developed to characterize the flaws in regions of a RPV. The regions include the main seam welds, repair welds, base metal, and the cladding at the inner surface of the vessel. This paper summarizes the available data and describes the treatment of these data to estimate flaw densities, flaw depth distributions, and flaw aspect ratio distributions. The methodology has generated flaw-related inputs for PFM calculations that have been part of an effort to update pressurized thermal shock (PTS) regulations. Statistical treatments of uncertainties in the parameters of the flaw distribution functions are part of the inputs to the PFM calculations. The paper concludes with a presentation of some example input files that have supported evaluations by USNRC of the risk of vessel failures caused by PTS events.
On the Interaction of Non-Coplanar Embedded Crack With Surface Crack in 3D Using FE and Multi-Level Sub-Structuring
Authors: Moussa Walied A.
Published: July 2013

The interaction and coalescence of multiple cracks may significantly affect the designed lives of aging pressure vessel structures. Knowledge of the growth behavior of interacting cracks is still limited. In this paper, a novel sub-modeling meshing algorithm is used in three-dimensional linear finite element analysis to investigate the interaction between two identical, non-coplanar, semi-elliptical cracks. One of these cracks is modeled as a surface crack while the other is modeled as an embedded crack under a weld toe. Both interacting cracks are assumed to be in an infinite plate subjected to a remote tension loading condition. The energy release rates (G) and the Stress Intensity Factors (SIF’s) for these cracks are calculated along the interacting crack-front. And, a parametric study involving the variation of the relative horizontal separation distance between the two interacting cracks is carried out for a specific crack depth to plate thickness ratio, a/t, of 0.2. The crack shape aspect ratio, a/c, is also varied in this study within a range that extend between 1.0 and 0.33. An empirical formula is derived that relates the effects of the relative positions of these cracks to their SIFs.
Thermal Residual Stresses Induced During Manufacturing Process of Fiber Reinforced Polymeric Composites
Authors: Xia Zihui , Zhang Yunfa , Ellyin Fernand
Published: July 2013

The evolution of thermal residual stresses induced during curing processing has been investigated. A micro-mechanical model of a cross-ply laminates is analyzed using viscoelastic finite element method. The polymer matrix is represented by a non-linear viscoelastic constitutive model. To study possible bounds of the residual stresses two types of analyses were carried out: one with temperature-independent and the other with temperature-dependent material constants. The results indicate that a higher cooling rate results in higher residual stresses in the laminates. However, due to the viscosity of the polymer matrix, the residual stresses relax with time and tend to an asymptotic small value irrespective of the different cooling rates. The average shrinkage strains and the coefficients of thermal expansion (CTE) of the composites, correspondingly, are also time-dependent and approach an asymptotic value after the stress relaxation process.
A pFFT Accelerated BEM Linear Strength Potential Flow Solver
Authors: Willis David J. , White Jacob K. , Peraire Jaime
Published: July 2013

In this paper the development of a linear shape function, Galerkin Boundary Element Method (BEM) for solving the direct potential flow integral equation around arbitrary 3-Dimensional bodies is described. The solution of the potential flow for both constant and linear shape functions over a triangulated body surface is examined. In order to facilitate a larger and more practical number of panels, an iterative GMRES [1] matrix solution method is coupled with a precorrected Fast Fourier Transform (pFFT) approximate matrix vector product (MVP)[2]. The pFFT algorithm is described and the differences in attaining MVP’s for linear and constant strength panel distributions are highlighted. A simple flat sheet wake model is included to solve the lifting body problem. The pFFT is shown to reduce the solution time to O(nlog(n)) operations (n is the number of panels). The results from flat panel surface representations of the body show that the convergence rate of the solution is at best O(n) for both linear and constant basis function representations of the solution. When the constant basis solution is sampled at the centroid of the panel, the error converges at a similar rate to the linear basis solution error, namely (O(n)); however, when the solution is sampled at surface points other than the centroid, the constant basis representation will converge at a slower rate O(n1/2), while the linear basis solution converges at a rate of O(n) for all points on the body.
Numerical Simulation of Blood Flow Through Stenosed Vessel
Authors: Onogi Kimie , Kohge Kazuhiro , Minemura Kiyoshi
Published: July 2013

This article illustrates numerical results on pulsating blood flow through moderately stenosed blood vessel. Two kinds of waveform, that is, a purely sinusoidal waveform and a non-sinusoidal one just like human blood flow are calculated for two cases of heart rate as 60 and 160 (1/s), and resultant flow behavior such as flow velocities, secondary flow, wall shear stress and pressure change are discussed. The abrupt changes in the pressure and wall shear stress occur on the throat of the stenosis, suggesting that this part is easily damaged by the effects when the heart rate is increased.
Hemodynamic Pressure Instabilities and Their Relation to Heart Auscultation
Authors: Kudriavtsev Vladimir , Polyshchuk Vladimir , Saynina Olga
Published: July 2013

We present work in progress results showing how CFD can be utilized to study heart sound acoustic signatures. Special emphasize is given to the dynamics of cardiac cycle, its fluid mechanics interpretation and to the structure of the heart sounds S1 and S2.
CFD Modeling of Combustion-Generated NOx in a Utility Furnace Firing Heavy Residual Fuel Oil
Authors: Wang David H. , Cremer Marc A. , Adams Brad R. , Santangeli Robert
Published: July 2013

Modeling a utility furnace firing heavy residual fuel oil is challenging due to the complex process associated with oil combustion, including droplet spray patterns, droplet heat up and vaporization, gas phase combustion of vaporized oil, enhanced radiative heat transfer due to potentially high soot levels, cenosphere formation and destruction, and NOx chemistry. This paper describes an oil combustion model developed at Reaction Engineering International (REI). The oil combustion model, taking oil spray characterization measurements as inputs, focuses on the aerodynamics and combustion characteristics of oil droplets and NOx chemistry. High soot levels generated from oil flames have been considered for radiative heat transfer. Cenosphere formation and destruction are not modeled since the combustion field, heat release, and NOx chemistry are not significantly influenced by these phenomena. The code has been applied to a 600 MW oil-fired utility boiler and some of modeling results are presented in this paper.
Direct Numerical Simulation and RANS Modeling of Turbulent Natural Convection for Low Prandtl Number Fluids
Authors: Otic´ I. , Gro¨tzbach G.
Published: July 2013

Results of direct numerical simulation (DNS) of turbulent Rayleigh-Be´nard convection for a Prandtl number Pr = 0.025 and a Rayleigh number Ra = 105 are used to evaluate the turbulent heat flux and the temperature variance. The DNS evaluated turbulent heat flux is compared with the DNS based results of a standard gradient diffusion turbulent heat flux model and with the DNS based results of a standard algebraic turbulent heat flux model. The influence of the turbulence time scales on the predictions by the standard algebraic heat flux model at these Rayleigh- and Prandtl numbers is investigated. A four equation algebraic turbulent heat flux model based on the transport equations for the turbulent kinetic energy k, for the dissipation of the turbulent kinetic energy ε, for the temperature variance θ2, and for the temperature variance dissipation rate εθ is proposed. This model should be applicable to a wide range of low Prandtl number flows.
Comparing Different Turbulence Modelling Approaches for Square Duct Simulations Using the Kiva Code
Authors: Huijnen V. , Somers L. M. T. , Baert R. S. G. , de Goey L. P. H.
Published: July 2013

In internal-combustion engines (ICE) the fluid dynamics is characterized by strong anisotropy. The standard two equation k–ε model is well known to be not appropriate in this case. A detailed study of the numerical modelling properties of the well known Kiva-3V code has been performed for two different approaches to anisotropic turbulence modelling. In the first approach a Smagorinsky-type LES model is evaluated. In the second approach a Time-Dependent RANS model has been adopted, using the Explicit Algebraic Stress Model of Gatski and Speziale [1]. For validation of both approaches numerical simulations of a turbulent flow in a square duct geometry are compared to DNS data. It is concluded from this work that the applied RANS approach is the best available practise to model the anisotropic properties of the fluid flow for ICE simulations as long as the computational resources to perform real LES simulations remain limited.
Numerical Simulation Study on the Asymmetric Structures of Oscillatory Flow Field in a Baffled Tube Reactor
Authors: Wu Yong-Wen , Wu Jia
Published: July 2013

The oscillatory flow in a baffled tube reactor provides a significant enhancement of radial transfer of momentum, heat and mass and a good control of axial back mixing at a wide range of net flow rate. But little has been known about reliable details of the three-dimensional structure of flow field in this kind of flow because most published studies in the area were based on the two-dimensional simulation techniques. This paper implemented a three-dimensional numerical simulation study on the asymmetry of flow pattern in the baffled tube reactor which was observed experimentally. A systematic study by numerical simulation was carried out which covered a range of oscillatory Reynolds number (Reo) from 100 to 5,000 and employed models respectively for laminar and turbulent flows. It was found in the simulation that under symmetric boundary conditions the transition from axially symmetric flow to asymmetric one depended on the numerical technique employed in simulation. With a structured grid frame the transition occurred at Reo much greater than that with an unstructured grid frame, for both laminar and turbulent flows. It is not rational that the onset of the transition changes with the accuracy of numerical technique. Based on the simulation results, it was postulated that the asymmetry appeared in simulations with symmetric boundary conditions might result from the accumulation of calculation errors but the asymmetry observed in experiments might result from the slight asymmetry of geometry which exists inevitably in any experiment apparatus. To explore the influence of the slight asymmetry of geometry, the effect of the eccentricity of baffles and the declination of oscillating boundary were studied by use of the finite volume method with a structured grid and adaptive time steps. The simulation result showed that both the eccentricity of baffles and the declination of oscillating boundary have obvious influence on the asymmetry of flow patterns for laminar and turbulent flow. More details were discussed in the paper.
Optical properties of solution-processed LaAlOx/Si films using spectroscopic ellipsometry
Authors: Kim Tae Jung , Hwang Soo Min , Yoon Jae Jin , Hwang Soon Yong , Park Han Gyeol , Kim Jun Young , Choi Junho , Kim Young Dong , Lee Seung Muk , Joo Jinho
Published: July 2013

The dielectric functions, ε, of amorphous LaAlOx (LAO) films grown by the sol–gel process are investigated using spectroscopic ellipsometry. The LAO precursor sols are prepared at a molar ratio of La:Al = 1:1 with different mole concentrations to control the film thickness. The films are deposited on p-type Si substrates treated with dilute HF, and the sols are sintered at 400 °C for 2 h in an ambient atmosphere. Room-temperature pseudodielectric function spectra, ⟨ε⟩, are obtained from 0.7 to 8.6 eV, and best fits of the data are obtained with the Tauc–Lorentz (TL) model. The authors observe an increase in both the real and imaginary parts of ε, a decrease in the TL threshold energy Eg, and an increase in film thickness with increasing mole concentration of the precursor solution.
Geometric Frustration of Icosahedron in Metallic Glasses
Authors: Hirata A. , Kang L. J. , Fujita T. , Klumov B. , Matsue K. , Kotani M. , Yavari A. R. , Chen M. W.
Published: July 2013

Order, Order

The structure of glassy materials, which are known to have short-range order but no long-range pattern, continues to be a puzzle. One current theory is that some glassy materials possess icosahedral ordering, a motif that cannot show translational periodicity.

Hirata
et al.

(p.
376
, published online 11 July) obtained diffraction patterns from subnanometer volumes in a metallic glass, which show some, but not all, of the expected features of an icosahedron. Simulations suggest that the patterns arise from icosahedrons distorted to include features of the face-centered cubic structure. This observation is different from the predictions of molecular dynamics simulations and provides pivotal information in understanding the competition between the formation of the globally inexpensive long-range order and the locally inexpensive short-range order.
Lentiviral Hematopoietic Stem Cell Gene Therapy in Patients with Wiskott-Aldrich Syndrome
Authors: Aiuti Alessandro , Biasco Luca , Scaramuzza Samantha , Ferrua Francesca , Cicalese Maria Pia , Baricordi Cristina , Dionisio Francesca , Calabria Andrea , Giannelli Stefania , Castiello Maria Carmina , Bosticardo Marita , Evangelio Costanza , Assanelli Andrea , Casiraghi Miriam , Di Nunzio Sara , Callegaro Luciano , Benati Claudia , Rizzardi Paolo , Pellin Danilo , Di Serio Clelia , Schmidt Manfred , Von Kalle Christof , Gardner Jason , Mehta Nalini , Neduva Victor , Dow David J. , Galy Anne , Miniero Roberto , Finocchi Andrea , Metin Ayse , Banerjee Pinaki P. , Orange Jordan S. , Galimberti Stefania , Valsecchi Maria Grazia , Biffi Alessandra , Montini Eugenio , Villa Anna , Ciceri Fabio , Roncarolo Maria Grazia , Naldini Luigi
Published: July 2013

Next-Generation Gene Therapy

Few disciplines in contemporary clinical research have experienced the high expectations directed at the gene therapy field. However, gene therapy has been challenging to translate to the clinic, often because the therapeutic gene is expressed at insufficient levels in the patient or because the gene delivery vector integrates near protooncogenes, which can cause leukemia (see the Perspective by

Verma

).

Biffi
et al.

(
1233158
, published online 11 July) and

Aiuti
et al.

(
1233151
; published online 11 July) report progress on both fronts in gene therapy trials of three patients with metachromatic leukodystrophy (MLD), a neurodegenerative disorder, and three patients with Wiskott-Aldrich syndrome (WAS), an immunodeficiency disorder. Optimized lentiviral vectors were used to introduce functional
MLD
or
WAS
genes into the patients' hematopoietic stem cells (HSCs) ex vivo, and the transduced cells were then infused back into the patients, who were then monitored for up to 2 years. In both trials, the patients showed stable engraftment of the transduced HSC and high expression levels of functional
MLD
or
WAS
genes. Encouragingly, there was no evidence of lentiviral vector integration near proto-oncogenes, and the gene therapy treatment halted disease progression in most patients. A longer follow-up period will be needed to further validate efficacy and safety.
Xk-Related Protein 8 and CED-8 Promote Phosphatidylserine Exposure in Apoptotic Cells
Authors: Suzuki Jun , Denning Daniel P. , Imanishi Eiichi , Horvitz H. Robert , Nagata Shigekazu
Published: July 2013

Whence the “Eat Me” Signal?

Cells are surrounded by a lipid bilayer, the composition of which is asymmetrical and serves as a marker of the physiological status of the cell. The phospholipid, phosphatidylserine (PtdSer), is normally found only on the inner leaflet of the membrane, but in dying cells it appears on the cell surface, thus providing the phagocytes tasked with cleaning up such cellular debris with a way to recognize cells undergoing cell death. Such movement of phospholipids within the membrane requires an elusive enzyme known as a scramblase.

Suzuki
et al.

(p.
403
; published online 11 July) identified an enzyme, Xkr8, which appears to act as a scramblase that promotes exposure of PtdSer on the surface of dying mammalian cells. Consistent with such a role, Xkr8 was activated after cleavage by caspase 3, a key protease that promotes apoptotic cell death. Genetic studies with the homolog of Xkr8 expressed in
Caenorhabditis elegans
indicated that the protein played a similar role in tagging dead cells in the nematode worm during development.
Draft Genome Sequences of Elizabethkingia meningoseptica
Authors: Matyi Stephanie A. , Hoyt Peter R. , Hosoyama Akira , Yamazoe Atsushi , Fujita Nobuyuki , Gustafson John E.
Published: July 2013

Elizabethkingia meningoseptica
is ubiquitous in nature, exhibits a multiple-antibiotic resistance phenotype, and causes rare opportunistic infections. We now report two draft genome sequences of
E. meningoseptica
type strains that were sequenced independently in two laboratories.
Genome Sequences of Three Atypical Xanthomonas campestris pv. campestris Strains, CN14, CN15, and CN16
Authors: Bolot Stéphanie , Roux Brice , Carrere Sébastien , Jiang Bo-Le , Tang Ji-Liang , Arlat Matthieu , Noël Laurent D.
Published: July 2013

Xanthomonas campestris
pv. campestris is the causal agent of black rot on
Brassicaceae
. The draft genome sequences of three strains (CN14, CN15, and CN16) that are highly aggressive on
Arabidopsis
have been determined. These genome sequences present an unexpected genomic diversity in
X. campestris
pv. campestris, which will be valuable for comparative analyses.
Divergent Human Papillomavirus Associated with Recurrent Respiratory Papillomatosis with Lung Involvement
Authors: Yuan Hang , Zhou Dan , Wang Jingang , Schlegel Richard
Published: July 2013

A divergent human papillomavirus (HPV), isolated from a lung lesion of a patient with recurrent respiratory papillomatosis, was fully cloned, sequenced, and genetically characterized. DNA analysis revealed that the HPV contained a 10.4-kb genome, with a duplication of 2,493 bp that includes partial L1-long control region (LCR)-E6-E7-partial E1 sequences.
Draft Genome Sequence of Arcticibacter svalbardensis Strain MN12-7
T
, a Member of the Family
Sphingobacteriaceae
Isolated from an Arctic Soil Sample
Authors: Shivaji S. , Ara Sreenivas , Prasad Sathish , Manasa B. Poorna , Begum Zareena , Singh Aditya , Kumar Pinnaka Anil
Published: July 2013

The 4.69-Mb genome sequence of
Arcticibacter svalbardensis
strain MN12-7
T
, isolated from an Arctic soil sample, is reported.
Complete Genome Sequences of an Avian Orthoreovirus Isolated from Guangxi, China
Authors: Teng Liqiong , Xie Zhixun , Xie Liji , Liu Jiabo , Pang Yaoshan , Deng Xianwen , Xie Zhiqin , Fan Qing , Luo Sisi
Published: July 2013

We report the complete genomic sequences of an avian orthoreovirus, strain GuangxiR1, isolated from a chicken flock in Guangxi Province, southern China, in 2000. Phylogenetic analyses suggest that the strain is closely related to the S1133 strain, which is associated with tenosynovitis, but is far different from strain AVS-B, which is associated with runting-stunting syndrome in broilers.
Draft Genome Sequence of
Frankia
sp. Strain BCU110501, a Nitrogen-Fixing Actinobacterium Isolated from Nodules of
Discaria trinevis
Authors: Wall Luis G. , Beauchemin Nicholas , Cantor Michael N. , Chaia Eugenia , Chen Amy , Detter J. Chris , Furnholm Teal , Ghodhbane-Gtari Faten , Goodwin Lynne , Gtari Maher , Han Cliff , Han James , Huntemann Marcel , Hua Susan Xinyu , Ivanova Natalia , Kyrpides Nikos , Markowitz Victor , Mavrommatis Kostas , Mikhailova Natalia , Nordberg Henrik P. , Nouioui Imen , Ovchinnikova Galina , Pagani Ioanna , Pati Amrita , Sen Arnab , Sur Saubashya , Szeto Ernest , Thakur Subarna , Wei Chia-Lin , Woyke Tanja , Tisa Louis S.
Published: July 2013

Frankia
forms a nitrogen-fixing symbiosis with actinorhizal plants. We report a draft genome sequence for
Frankia
sp. strain BCU110501, a nitrogen-fixing actinobacterium isolated from nodules of
Discaria trinevis
grown in the Patagonia region of Argentina.
Muscle injury rates in professional football increase with fixture congestion: an 11-year follow-up of the UEFA Champions League injury study
Authors: Bengtsson Håkan , Ekstrand Jan , Hägglund Martin
Published: July 2013

Background

The influence of fixture congestion on injury rates and team performance has only been scarcely investigated.

Aim

To study associations between recovery time and match load and injury rates and team performance in professional football.

Methods

Exposure and time loss injuries were registered prospectively from 27 teams over 11 seasons. Matches were grouped according to recovery days before each match (≤3 vs >3 days, and ≤4 vs ≥6 days). Injury rates and team performance were compared between groups. Match load in match sequences containing five consecutive matches was determined by the number of days separating the first match and the last training session during that match sequence. Linear regression was used to study associations between match load and injury rates and team performance.

Results

Team performance showed no association with match load, or recovery days prior to matches, except for Europa League matches that indicated more matches lost with short recovery (≤3 days) (p=0.048). Total injury rates and muscle injury rates were increased in league matches with ≤4 days compared with ≥6 days’ recovery (RR 1.09, 95% CI 1.00 to 1.18, and RR 1.32, 95% CI 1.15 to 1.51, respectively), specifically hamstring and quadriceps injuries. High match load was associated with increase in muscle injury rate in matches in the same match sequence (p=0.012), and increase in ligament injury rate in training in the subsequent match sequence (p=0.003).

Conclusions

Fixture congestion was associated with increased muscle injury rates but had no, or very limited, influence on team performance.
Motor impairment and its relationship to fitness in children
Authors: Morris Martyn , Dawes Helen , Howells Ken , Janssen Roel
Published: July 2013

Objectives

The aim of this work was to explore the physiological and perceptual limits to exercise in children with varying degrees of motor impairment, and the relationships to measures of health.

Design and methods

In a group comparison design, 35 boys aged 12–15 years completed the Movement ABC test for the assessment of motor impairment, followed by an incremental cycle ergometer test to exhaustion for the assessment of maximal oxygen uptake (VO2peak), respiratory exchange ratio (RER), heart rate (HR) and rating of perceived exertion (RPE). Ten participants classified as having either high or no motor impairment also performed a maximal voluntary isometric contraction (MVIC) for the assessment of lower limb extensor strength.

Results

18 boys were classified as having high motor impairment. There was a significant difference inpeak (34.9 vs 48.5 mL kg/min),workload (12.5 vs 10.0 mL W), maximal HR (176 vs 188 bpm), maximal oxygen pulse (12.1 vs 15.9 mL beat) and MVIC (5.7 vs 9.1 Nm kg) between the high and non-motor impaired participants, respectively, (p<0.05). There was no significant difference in the RER or RPE between groups.

Conclusions

When performing cycling ergometry, perceived exertion was not a limiting factor in children with high motor impairment. The lower maximal HR, coupled with reduced movement efficiency and muscle strength reported in this group, suggests that exercise is limited by impairment at the muscular level. This finding was supported by high RER values despite low maximal HR values attained at exercise cessation and reduced maximal strength. Perception of effort is not heightened in children with high motor impairment and future-exercise interventions should be focused on improving muscular condition in these participants to enable them to be better prepared to engage in physical activity for health.
Decreasing pH of mammary gland secretions is associated with parturition and is correlated with electrolyte concentrations in prefoaling mares
Authors: Canisso I. F. , Ball B. A. , Troedsson M. H. , Silva E. S. M. , Davolli G. M.
Published: July 2013

The objectives of this study were to determine pH of the mammary gland secretions and the corresponding electrolyte concentrations in prefoaling mares. Pregnant mares (seven primiparous and seven multiparous) were monitored daily from 310–320 days of gestation until parturition. Prefoaling mammary gland secretions were collected, and pH was immediately determined with a pH meter and pH strip test. An aliquot of prefoaling mammary secretions was frozen and stored until further analyses. After parturition, samples from day −4 to 0 (day of foaling) were thawed and electrolyte concentrations (ie, Ca2 +, Mg2 +, Na+, K+ and Cl−) were determined with an automated analyser. Data were analysed via a mixed model with the mare as a random effect. Correlations were determined between pH and electrolyte concentrations by the Pearson product‐moment for each pair. There was significant reduction in pH of mammary secretions on the day of foaling (P<0.0001), and most mares (11/14) with a pH ≤7 foaled within 24 hours. There was high correlation between the two pH methods (r=0.93). Additionally, there were significant (P<0.05) increases in Ca2+ and K+ concentrations, and significant decreases in Na+ and Cl− concentrations from one day before to the day of foaling. The pH of mammary secretions was highly and significantly (P<0.001) correlated with Na+ (r=0.87), Cl− (r=0.85), Ca2+ (r=−0.88); and K+ (r=−0.80) concentrations, and moderately correlated with Mg2+ (r=−0.58). Daily evening pH measure of the mammary gland secretions can predict foaling in most mares.
GENERALIZATION OF THE PHRAGMÉN–LINDELÖF THEOREMS FOR SUBFUNCTIONS
Authors: QIAO LEI , PAN GUOSHUANG
Published: July 2013

In this paper, we consider the Phragmén–Lindelöf theorem for subfunctions, associated with the stationary Schrödinger operator. Meanwhile, the integral representations and a-harmonic majorants of them are also given.
THE UNIVERSAL CHARACTER RING OF THE (-2, 2m + 1, 2n)-PRETZEL LINK
Authors: TRAN ANH T.
Published: July 2013

We explicitly calculate the universal character ring of the (-2, 2m + 1, 2n)-pretzel link and show that it is reduced for all integers m and n.
ADDRESSING MEMORY EFFECT FOR RAIL-TO-RAIL COMPARATOR WITH NEAR-THRESHOLD SUPPLY VOLTAGE
Authors: RAMAMOORTHY SARAVANAN , WANG HAIBO
Published: July 2013

Ultra-low voltage comparators with rail-to-rail input ranges are critical components in the design of low-voltage low-power analog to digital converters (ADCs). This paper investigates the memory effect of a commonly used comparator when its power supply is scaled down to near transistor threshold voltage levels. It also studies when such memory effects are most likely to occur during the conversion sequences of successive approximation register (SAR) ADCs. Subsequently an improved comparator design is presented to overcome the memory effect with near-threshold voltage power supply. The impacts of the proposed design modification on comparator speed, offset voltage and power consumptions are discussed. Based on a 0.13 μm CMOS technology and with a 0.5 V power supply, the proposed comparator is compared with the original comparator in terms of memory effect, speed, power consumption and input offset voltage. The integral and differential nonlinearity (INL and DNL) of 10-bit SAR ADCs with using the proposed and original comparators are also compared.
A SYSTEMATIC FLOW FOR DEVELOPING TOTALLY SELF-CHECKING ARCHITECTURES FOR SHA-1 AND SHA-2 CRYPTOGRAPHIC HASH FAMILIES
Authors: ATHANASIOU GEORGE S. , THEODORIDIS GEORGE , GOUTIS COSTAS E. , MICHAIL HARRIS E. , KASPARIS TAKIS
Published: July 2013

Hash functions are among the crucial modules of modern hardware cryptographic systems. These systems frequently operate in harsh and noisy environments where permanent and/or transient faults are often causing erroneous authentication results and collapsing of the whole authentication procedure. Hence, their on-time detection is an urgent feature. In this paper, a systematic development flow towards totally self-checking (TSC) architectures of the most widely-used cryptographic hash families, SHA-1 and SHA-2, is proposed. Novel methods and techniques are introduced to determine the appropriate concurrent error detection scheme at high level avoiding gate-level implementations and comparisons. The resulted TSC architectures achieve 100% fault detection of odd erroneous bits, while, depending on the designer's choice, even number of erroneous bits can also be detected. Two representative functions of the above families, namely the SHA-1 and SHA-256, are used as case studies. For each of them, two TSC architectures (one un-optimized and one optimized for throughput) were developed via the proposed flow and implemented in TSMC 0.18 μm CMOS technology. The produced architectures are more efficient in terms of throughput/area than the corresponding duplicated-with-checking ones by 19.5% and 23.8% regarding the un-optimized TSC SHA-1 and SHA-256 and by 20.2% and 24.6% regarding the optimized ones.
LUMINOSITIES OF RADIO PULSARS
Authors: BAGCHI MANJARI
Published: July 2013

Luminosity is an intrinsic property of radio pulsars related to the properties of the magnetospheric plasma and the beam geometry, and inversely proportional to the observing frequency. In traditional models, luminosity has been considered as a function of the spin parameters of pulsars. On the other hand, parameter independent models like power law and lognormal have been also used to fit the observed luminosities. Some of the older studies on pulsar luminosities neglected observational biases, but all of the recent studies tried to model observational effects as accurately as possible. Luminosities of pulsars in globular clusters (GCs) and in the Galactic disk have been studied separately. Older studies concluded that these two categories of pulsars have different luminosity distributions, but the most recent study concluded that those are the same. This paper reviews all significant works on pulsar luminosities and discusses open questions.
ISOTROPIZATION IN CHAPLYGIN MATTER UNIVERSES CONNECTED BY A WORMHOLE
Authors: MOKEEVA ANNA , POPOV VLADIMIR
Published: July 2013

Chaplygin anisotropic matter governing the cosmological evolution in two identical universes with an intermediate static spherically symmetric region is considered. The static region contains a wormhole allowing one to pass between two horizons. The metric in the nonstatic region represents a kind of an anisotropic Kantowski–Sachs cosmological model starting from a horizon instead of the initial singularity. A classification of the cosmologies with a monotonic late stage is presented. It is shown that only one scenario can involve a de Sitter regime. The scales in the de Sitter phase allows one to describe the earliest accelerated expansion on the classical level.
ROLE OF THE LINEAR LOSSES AND NONLINEAR MAGNETIC SUSCEPTIBILITY IN THE MODULATIONAL INSTABILITY IN NONLINEAR METAMATERIALS
Authors: ZHAO LU , XIE DONGLEI , WU XINGHUA , DAI XIAOYU , XIANG YUANJIANG
Published: July 2013

We analyze modulation instability (MI) in lossy metamaterials (MMs) with both nonlinear polarization and nonlinear magnetization. A detailed discussion on the role of the nonlinear electric polarization, nonlinear magnetic susceptibility and linear loss on the MI is presented. It is found that the nonlinear magnetization and linear loss play an important role in determining the MI in nonlinear MMs. Linear stability analysis predicts that MI may occur in the MMs with self-defocusing nonlinearity due to the negative-index of MMs. In particular, the nonlinear magnetic susceptibility changes the generation condition of MI seriously, it can be used to enhance or depress the MI depending on the sign of the nonlinear magnetic susceptibility. Finally, the influence of the loss in MMs on the MI is discussed.
CALCULATIONS AND EXPERIMENTAL STUDIES OF THE AGGREGATION OF MOLECULES OF LIQUID ACETONE BY SPECTRA OF RAMAN SCATTERING
Authors: TUKHVATULLIN F. H. , TASHKENBAEV U. N. , JUMABAEV A. , HUSHVAKTOV H. , ABSANOV A. , SHARIFOV G.
Published: July 2013

Experimental studies of the Raman scattering of the band of C = O vibrations of acetone (1710 cm–1) showed that the parallel and perpendicular polarized components have a large half-width (respectively, 11.6 and 18 cm–1) and also the bands' maxima of these components are shifted by ~5 cm–1. In the neutral solvent (heptane), the difference of the maxima position of the bands decreases. Calculations showed that the molecules of acetone can aggregate to form a dimer with the energy gain of 10.1 kJ/mole. In the dimer several hydrogen bonds are formed between the oxygen atom of one molecule and the hydrogen atoms of CH3 -group of another molecule. In an aqueous mixture of acetone, according to calculations, there is a possibility for formation of dimers and closed trimer aggregates with the energy gain, respectively, 19.1 and 45.8 kJ/mole. Calculation showed that symmetric and antisymmetric O–H vibrations of water are displaced in the interaction with acetone to lower frequencies, respectively, to 3808.4 and to 3931.8 –1.
HAND GESTURE RECOGNITION TOWARDS VOCABULARY AND APPLICATION INDEPENDENCY
Authors: RAUTARAY SIDDHARTH SWARUP , AGRAWAL ANUPAM
Published: July 2013

Traditional human–computer interaction devices such as the keyboard and mouse become ineffective for an effective interaction with the virtual environment applications because the 3D applications need a new interaction device. An efficient human interaction with the modern virtual environments requires more natural devices. Among them the "Hand Gesture" human–computer interaction modality has recently become of major interest. The main objective of gesture recognition research is to build a system which can recognize human gestures and utilize them to control an application. One of the drawbacks of present gesture recognition systems is being application-dependent which makes it difficult to transfer one gesture control interface into multiple applications. This paper focuses on designing a hand gesture recognition system which is vocabulary independent as well as adaptable to multiple applications. This makes the proposed system vocabulary independent and application independent. The designed system is comprised of the different processing steps like detection, segmentation, tracking, recognition, etc. Vocabulary independence has been incorporated in the proposed system with the help of a robust gesture mapping module that allows the user for cognitive mapping of different gestures to the same command and vice versa. For performance analysis of the proposed system accuracy, recognition rate and command response time have been compared. These parameters have been considered because they analyze the vital impact on the performance of the proposed vocabulary and application-independent hand gesture recognition system.
Sunday Stone: an enduring metaphor of mining diseases and underground mining conditions
Authors: Pearn John H. , Gardner-Thorpe Christopher
Published: July 2013

The occupational hazards of miners include acute trauma and death from rock falls, water inundation, explosions and the long-term effects of progressive pulmonary disease. One of the most evocative of records of the dust-laden atmosphere in which coalminers work is Sunday Stone. Specimens of Sunday Stone are preserved in the Great North Museum, the ‘Hancock’, managed by Tyne and Wear Archives and Museums in Newcastle-upon-Tyne. Sunday Stone is the name given to calcareous deposits that formed inside wooden pipes carrying wastewater from the collieries of Durham and Northumberland. Sunday Stone is composed of alternating light and dark bands, each double-band representing one 24-hour period. Water seeping into the working mines became laden with coal dust and dissolved mineral salts. The daily dark band corresponded to the working day (the ‘fore’ and ‘back’ shifts) with its heavy dust-laden atmosphere. The broader light-coloured band was laid down on Sundays during coalface downtime. Sunday Stone today comprises an enduring metaphor of the mining industry, and specimens remain as a silent but permanent witness to the conditions in which millions of underground coalminers have worked and often work today. In these banded patterns one sees the progressive struggle to improve mine safety and ventilation and the evolution of industrial preventive medicine.
Low-Energy Measurements of the Weak Mixing Angle
Authors: Kumar K.S. , Mantry Sonny , Marciano W.J. , Souder P.A.
Published: July 2013

We review the status of precision measurements of weak neutral-current interactions, mediated by the Z0 boson, at Q2≪M2Z. They can be used to extract values for the weak mixing angle [Formula: see text], a fundamental parameter of the [Formula: see text] electroweak sector of the Standard Model. Apart from providing a comprehensive test of the electroweak theory at the quantum-loop level, such measurements allow indirect access to New Physics effects at and beyond the TeV scale. After providing a theoretical introduction and a brief overview of the three most precise low-Q2 weak mixing angle determinations, we describe the ongoing experimental program and prospects for future, more sensitive studies. We also compare the sensitivities of planned and proposed measurements with physics beyond the Standard Model.
Rechargeable, Lithium-Ion Molten Salt Battery for High Temperature Applications
Authors: Caja Josip , Dunstan T Don J , Caja Mario
Published: July 2013

A CC size rechargeable lithium-ion molten salt cell, which can operate from room temperature to 150oC, has been developed. The cell has an open circuit voltage 2.3 V and capacity 2.2 Ah. The cell showed high coulombic efficiency (99% at 100oC); however, efficiency decreased with increase in temperature. Its lifetime depended on operating temperature; it had higher lifetime at lower temperature. At 120oC the cell delivered 120 full charge/discharge cycles retaining 80% capacity. The cells were operated at different temperatures using both high currents (2.5 A) and lower currents (e.g. 220 mA). They have also been tested in the pulse mode (0.8, 1.2, and 2.5 A) at ambient temperature, 80oC and 145oC. A battery of 20 cells was built and successfully tested in the oil field. This is the first molten salt rechargeable lithium-ion cell built and tested for high temperature applications.
Combined In-Situ X-ray Absorption Spectroscopy and First-Principles Calculation Studies on Local Structural and Electronic Structural Alternations of LiNi1/3Co1/3Mn1/3O2
Authors: Mogi Masato , Kubobuchi Kei , Matsumoto Masashi , Nishijima Manabu , Imai Hideto , Yamamoto Tomoyuki , Matsumoto Takashi , Nitta Yoshiaki
Published: July 2013

We report a result of combined in-situ x-ray absorption spectroscopy (XAS) and first-principles calculation study on LiNi1/3Co1/3Mn1/3O2 cathode material, especially focusing on the roles of individual transition metals and oxygen for the battery reactions The theoretical X-ray Absorption Near Edge Structure (XANES) spectra simulations of LixNi1/3Co1/3Mn1/3O2 have been well reproduced experimental in situ XANS spectra, and behaviors of XANES spectral shapes are reasonably explained with electronic structure considerations. Results of such analysis revealed that Ni mainly contribute to the battery-redox-reaction, while Co contribute only at high potential regions, and Mn does not contribute to the reaction.
Impact of the Calendering Process on the Interfacial Structure and the Related Electrochemical Performance of Secondary Lithium-Ion Batteries
Authors: Haselrieder Wolfgang , Ivanov Stoyan , Christen Daniel Klaus , Bockholt Henrike , Kwade Arno
Published: July 2013

Graphite electrodes, containing 8 wt% binder and 4 wt% conductive additives, manufactured from one batch of a continuous coating and drying process in technical scale, are investigated under variation of specific compression rates. The influence of the calendering process is studied in terms of surface morphology, mechanical, structural and electrochemical properties. Graphite electrodes are found to be sensitive to compaction and a compression rate of 10 % was identified to be beneficial to long term cycling stability, while the impact on power performance was found not to be affected to a high extent. The change of pore structure for specific pore size ranges and the deformation of active material are identified to be crucial factors negatively influencing electrochemical performance. Plastic and elastic deformation energies of the electrode coating layer are derived by nanoindentation. This method is suitable to quantify the electrodes’ mechanics and undergoing particle deformation caused by calendering.
Cycling Behavior of a High Voltage Spinel Using an Original Three Electrodes Li1-xNi0.4Mn1.6O4//Li//LiNi0.4Mn1.6O4 Symmetric Cell: Application to LiNi0.4Mn1.6O4 Electrolyte Interface Degradation Studies
Authors: Demeaux Julien , Lemordant Daniel , Caillon-Caravanier Magaly , Galiano Hervé , Claude-Montigny Bénédicte
Published: July 2013

The interface between LiNi0.4Mn1.6O4 and alkylcarbonate-based electrolytes is investigated by ab initio calculations, ICP-AES measurements and electrochemical tests. Interface degradation is known to occur by both the electrolyte oxidation and the Mnn+ and Nin+ ion dissolution. Nevertheless, EC or PC oxidation, leading to a polymeric film formation, is able to contribute to the interface stabilization. Besides Li//LiNi0.4Mn1.6O4 half-cells, Li1-xNi0.4Mn1.6O4//LiNi0.4Mn1.6O4 symmetric cells are used in order to eliminate the effects from the strong reducing nature of lithium on the electrolyte. Systematic comparisons of fading and coulombic efficiency show that the main degradation mechanism in half-cells is the electrolyte oxidation, as a consequence of the continuous precipitation of metal ion-based compounds on the lithium electrode. The symmetric cell studies indicate that redox shuttles (Mn+ ↔ M(n-1)+, M=Mn or Ni) are mainly responsible for the LiNi0.4Mn1.6O4/electrolyte interface degradation despite the possible presence of a polymeric film. Symmetric cells also confirm EC superiority over other alkylcarbonates at the LiNi0.4Mn1.6O4 interface.
Well Controlled Array of Si Nanopillar with Metal Core as Negative Electrode for Lithium-Ion Batteries
Authors: Oguni Teppei , Tajima Ryota , Osada Takeshi , Muraoka Taiga , Kurata Motomu , Sasagawa Shinya , Adachi Shunsuke , Takeuchi Toshihiko , Kakehata Tetsuya , Momo Junpei , Moriwaka Tamae , Takahashi Minoru , Yamazaki Shunpei
Published: July 2013

A promising Si negative electrode, that is a well controlled array of Si nanopillar, was fabricated by a semiconductor process. The electrochemical property of this electrode was examined by charge-discharge measurements, SEM and TEM observations. Although the result of charge-discharge measurements of this Si nanopillar electrode was comparable to those of a flat thin film Si electrode, pulverization of the Si film was successfully suppressed in the Si nanopillar electrode. In the Si thin film electrode, only the upper half of the Si film seemed to have reacted, and this caused cracking and pulverization. By contrast, in the Si nanopillar electrode, the entire Si film seemed to have reacted, and cracking and pulverization were suppressed. The experimental results demonstrated that the Si nanopillar electrode has a suitable structure for a Si negative electrode.
High Performance Lithium-Ion Battery Using Graphene Net Electrode
Authors: Yamakaji Masaki , Todoriki Hiroatsu , Ikenuma Tatsuya , Saito Yumiko , Yukawa Mikio , Yatabe Rika , Momo Junpei , Moriwaka Tamae , Nanba Kenryo , Takahashi Minoru , Yamazaki Shunpei
Published: July 2013

An electrode using graphene oxide as a conductive additive exhibits high power and high energy density because graphene oxide has high dispersibility and forms conductive paths easily, compared with graphene and other carbon materials like acetylene black. Graphene oxide also shows the same effect as carbon coating when used as a conductive additive in a LiFePO4 electrode. In this work the LiFePO4 electrode using graphene oxide succeeds in exhibiting discharge capacities of 150 mAh/g at discharge rate of 170 mA/g (1 C). In addition, the LiFePO4 electrode using graphene oxide enables a reduction in carbon materials, because GO exhibits the effect as a conductive additive even in small amounts and does not require carbon coating of LiFePO4. This leads to an increase in the capacity of electrode. Thus, graphene oxide is effective in providing a LiFePO4 electrode having both high power and high energy density.