bluuebunny/crossref_metadata_2025 huggingface dataset:
Simplified Computation of Creep Damage Propagation
Authors: Marriott Douglas L. , Stumph Herbert E. , Sreeranganathan Arun , Matice Christopher J.
Published: December 2016

The commonly accepted approach to dealing with material damage as the cause of structural failure is to treat the most highly distressed location in the structure as an equivalent simple test and to define failure of the structure as a whole as being failure at that point location.

The exception to this rule is plastic deformation. Yielding at a point was recognized several decades ago as being an excessively conservative definition of component failure and it is now standard design practice to accept failure as being the limit load, which is only reached, sometimes after extensive propagation of a plastic zone.

Other material failure mechanisms also occur after a finite period of damage propagation, but this additional strength, or life, is not usually taken into account, partly because the damage mechanisms themselves are not always well defined, and partly because of the computational difficulty involved in assessing the propagation of damage.

Creep rupture falls into the category of a mechanism which can enjoy an extensive period of damage propagation before structural failure occurs, but the difficulty of evaluating it quantitatively has meant that it continues to be dealt with as essentially a point failure phenomenon.

Relatively recently, many of the problems associated with assessing creep damage have been resolved, on the material side by increased use of so-called “continuum damage mechanics” based models such as Kachanov and Omega and, on the computational side, by the exponential growth in the capabilities of advanced Finite Element Analysis. It is now possible in principle to trace the entire life of a complex component, down to final disintegration. However, this capability still comes at a significant cost, and there is still room for simplification in order to bring this capability to a wider range of potential users.

This paper describes a process for evaluating the propagation of creep damage, down to the point of total disintegration, using approximations which exist within the standard capabilities of a typical FE design package. This innovation does not do anything that cannot be done today using the full repertoire of computational tools that exist, notably user subroutines, but provides a simpler platform which can be used to push damage evaluation further into the activities of day-to-day design with a significant reduction in the resource allocation currently required to do the job.

Results are compared with creep experiments on notched bars.
Study on Mean Stress Effects for Design Fatigue Curves
Authors: Asada Seiji , Ogawa Takeshi , Higuchi Makoto , Kanasaki Hiroshi , Takada Yasukazu
Published: December 2016

In order to develop new design fatigue curves for austenitic stainless steels, carbon steels and low alloy steels and a new design fatigue evaluation method that are rational and have a clear design basis, the Design Fatigue Curve (DFC) subcommittee was established in the Atomic Energy Research Committee in the Japan Welding Engineering Society. Mean stress effects for design fatigue curves are to be considered in the development of design fatigue curves. The Modified Goodman approach for mean stress effects is used in the design fatigue curves of the ASME B&PV Code. Tentative design fatigue curves were developed and studies on the effect of mean stress and design factors are on-going. Development of design fatigue curves, effect of mean stress and design factors is needed to establish a new fatigue design evaluation method. The DFC subcommittee has studied correction approaches for mean stress effects and the approaches of modified Goodman, Gerber, Peterson and Smith-Watson-Topper were compared using test data in literature. An appropriate approach for mean stress effects are discussed in this paper.
Failure Probability Analysis of Aged Piping Using Probabilistic Fracture Mechanics Methodology Considering Seismic Loads
Authors: Yamaguchi Yoshihito , Katsuyama Jinya , Li Yinsheng
Published: December 2016

Several nuclear power plants in Japan have been operating for more than 30 years and cracks due to age-related degradations have been detected in some piping systems during in-service inspections. Furthermore, several of them have experienced severe earthquakes in recent years. Therefore, failure probability analysis and fragility evaluation for piping systems, taking both age-related degradations and seismic loads into consideration, has become increasingly important for the structural integrity evaluation and the seismic probabilistic risk assessment.

Probabilistic fracture mechanics (PFM) is recognized as a rational methodology for failure probability analysis and fragility evaluation of aged piping, because it can take the scatters and uncertainties of influence parameters into account. In our Japan Atomic Energy Agency (JAEA), a PFM analysis code PASCAL-SP was developed for aged piping considering age-related degradations. In this study, we improved PASCAL-SP for the fragility evaluation taking both age-related degradations and seismic loads into account. The details of the improvement of PASCAL-SP are explained and some example analysis results of failure probabilities, fragility curves and a preliminary investigation on seismic safety margin are presented in this paper.
Comparison of Ductility-Dip Cracking to Computer Modeling With SysWeld™ in a Narrow Groove Multi-Pass Weld
Authors: McCracken Steven L. , Tatman Jonathan K.
Published: December 2016

Ductility-dip cracking (DDC) in high-chromium nickel-base weld metals has been an issue during fabrication and repair of nuclear power plant components for many years. DDC is a solid-state cracking phenomenon and several theories have been proposed for the mechanism. The research conducted to develop DDC theories has primarily been performed using test methods involving small-scale specimens that may not replicate all the welding conditions and factors that cause DDC. Due to the complexities of welding, there are potentially significant differences in the applied strain, strain rates, stresses, and thermal cycles that occur with small scale test methods and actual multi-pass welding conditions. EPRI is working to devise a method to predict DDC susceptibility in multi-pass high-chromium nickel-base welds and to develop procedures and techniques that minimize the occurrence of DDC — a key issue in the nuclear welding industry that has yet to be fully resolved. The primary aim is to design a weld mockup that replicates strain, strain-rates, stresses, and thermal cycles that occur in multi-pass field welds and which produces DDC in predicted weld regions. If successful, the data from this work will be used to assist in development of a simplified field deployable test which can effectively screen for DDC susceptibility. For the first phase of this work multi-pass narrow groove mockups using GTAW and filler metals 52 and 52M were made with precise heat input and bead placement controls to isolate the occurrence of DDC to a known region in the weld deposit. To assist with understanding the correlation between strain accumulation and the occurrence of DDC, computer modeling using SysWeld™, with validated weld parameter inputs, was used to simulate the narrow groove mockup weld. Comparison of DDC occurrence to the model results suggests that multiple reheat cycles in the ductility-dip temperature range accumulate plastic strains during both the on-heating and on-cooling portions of the reheat cycles, resulting in a strain ratcheting effect. It is postulated that this strain ratcheting exhausts the strength of the grain boundaries within the excessively reheated weld regions, which, when combined with the shear stress induced at the grain boundaries during the ratcheting events, promotes DDC.
Environmentally-Assisted Fatigue Analysis Using a Strain-Based Approach
Authors: Gilman Timothy , Ku Francis
Published: December 2016

Traditional design fatigue analyses of pressure vessels and piping equipment have typically used linear-elastic stress analyses, where the stresses caused by various loads, such as thermal, pressure, bending moments, etc. are combined using the principle of linear superposition. Based on high stress locations, geometric and material discontinuities, and other engineering judgements, stress classification lines (SCLs) were defined for where fatigue usage factors would be calculated. It was then necessary to apply simplified elastic-plastic penalty factors, based on the through-wall linearized stresses, to the peak stress amplitudes, in order to account for the nonlinear behavior of materials. Nonlinear finite element analysis that directly calculates strains were not typically used, because of computing and material modeling limitations. However, such analyses, even for complex three-dimensional structures, have become much more practical today with advancements in computing speed and storage capacity. ASME Section III Subarticle NB-3200 includes a provision for performing nonlinear (or “plastic”) analysis (NB-3228.4(c)), but little to no guidance is provided for how to perform the analysis itself. In addition, the procedure for computing the strain range, as currently written in the Code, has been identified as being limited to a uniaxial stress condition and is fundamentally inconsistent with the traditional elastic methodology. This paper provides a proposal for an improved approach for computing fatigue usage and strain rates using nonlinear plastic analysis. Additional guidance for performing these analyses is provided, as they are expected to be used more frequently into the future.
Analysis of Maximum Elasto-Plastic Response of Multi-Degree-of-Freedom Oscillators Based on a Modal Combination of Equivalently Linearized Response of Each Mode
Authors: Taniguchi Tomoyo , Nishiraku Hiroki , Ono Yusuke
Published: December 2016

This study develops a new analytical method for evaluating maximum elasto-plastic displacement of multi-degree-of-freedom (MDOF) oscillators under the action of base excitation based on a modal combination. The essence is that modal frequencies, shapes and damping during yielding of any member of the MDOF oscillators are readily specified by the modal analysis with the secondary stiffness of the members being yielded. In addition, assuming that a bilinear hysteresis may describe the force-displacement relationship of each mode, an equivalently linearized system consisting of a single-degree-of-freedom (SDOF) oscillator is introduced to approximate maximum elsato-plastic displacement of each mode. Employing the SRSS-rule, the maximum elasto-plastic displacement of the MDOF oscillator subjected to Kobe-NS accelerogram is calculated and compared with that computed by the commercial software. Applicability of the proposed method to evaluating maximum elasto-plastic displacement of the MDOF oscillator is thoroughly discussed.
Residual Stress Measurements Using the Contour, Deep-Hole Drilling and Neutron Diffraction Methods in T-Section Specimens
Authors: Serasli Karim , Cave Douglas , Kingston Ed
Published: December 2016

The presence of high magnitude residual stresses in welded components causes material degradation, local yielding and plastic deformation. Their presence provides the potential for premature failure and compromises the integrity of a structure. This paper presents a review of work carried out to ascertain the residual stresses present within T-section specimens, made from ferritic steel, in their as-welded condition. The standard and incremental deep hole drilling (DHD and iDHD) techniques, the neutron diffraction (ND) and the contour method were applied to characterise the residual stresses in the regions in and around the two fillet welds of the specimens and the surrounding parent material within which the balancing residual stresses needed to be measured. The results of these measurements are presented and compared to highlight agreements and discrepancies in the measured residual stress distributions using these different techniques. A compendium of measurements at a similar location in various T-sections and their comparison with the BS7910 standard show that the measured longitudinal distributions are similar despite the observed scatter. Finally, this paper briefly attempts to investigate and discuss the technical challenges identified when applying the contour method to complex geometry components. The constraint of the specimen during the wire electro-discharge machining (EDM) process, the quality of the wire EDM cut made and the analysis of the raw data for the conversion into residual stresses directly affect the accuracy of the contour method results. The identification and investigation of these challenges lead to continuous improvements of the contour method procedure and reduce uncertainties of the measurement.
Bonding Temperature Condition Dependence of Strength Improvement Effect by Decrease of Metal Thickness in Ceramic to Metal Joint System
Authors: Tateno Masayoshi , Tominaga Takashi
Published: December 2016

This study provides effects of bonding temperature conditions on practical strength in ceramic to metal joint system made by two stages bonding process. Ceramic to metal joint system is required to reduce the residual stress near the edge of the interface and to improve bonding strength.

The two stages bonding process, which was proposed in PVP2015-45822, can be a useful method to prevent the residual stress from increasing. This process consists of two stages, the first bonding process defined as a ceramic is bonded to thin metal layer at high temperature and the secondary process defined as a thick metal is bonded to the thin metal layer of the joint at lower temperature. It is necessary to provide effects of thickness of thin metal layer on the practical bonding strength in various combinations of the first and the secondary bonding temperature conditions.

Past experimental results showed the practical bonding strength would be dominated by the residual stress near the edge of the interface between the thin metal layer and the ceramic. The residual stress can be associated with the first and/or the secondary bonding temperature conditions. Setting the optimum metal thickness improves the bonding strength independent of the bonding temperature conditions in the limited conditions.

This paper provided dependence of the optimum metal layer thickness on the first and the secondary bonding temperature conditions was clarified experimentally. It also found effective metal thickness, which is capable of strengthening the siliconnitride to nickel joint system, in the combination of the first bonding temperature ranged over from 880°C to 980°C and the secondary bonding temperature ranged over from 600°C to 700°C.

It appeared the first bonding temperature and the secondary one are set at the higher, the optimum metal thickness becomes smaller. The result showed that decreasing metal thickness possesses similar effect to decreasing bonding temperature for reducing the thermal residual stress. Reducing the residual stress is capable of strengthening the part of the edge of the interface on the ceramic side. Setting the metal layer thinner should be applied for producing the high strength ceramic to metal joint system.

The two stages bonding process can contribute to achieve the high strength bonded dissimilar materials by setting the optimum thin metal thickness.
Evaluation of Fatigue Crack Growth Curves in Existing Codes and a Proposed Modification Based on Experimental Data of Cr-Ni-Mo-V Steel Welded Joints
Authors: Du Yan-Nan , Zhu Ming-Liang , Xuan Fu-Zhen , Tu Shan-Tung
Published: December 2016

A comparison of currently available codes for assessment of fatigue crack growth, including ASME (America Society of Mechanical Engineers) SEC. XI, FKM (Forchungskuratorium Maschinenbau) guideline, WES (Japan Welding Engineering Society) 2805, BS7910 and JSME (The Japan Society of Mechanical Engineers), was carried out by paying attention to the suitability of application and the easiness to obtain the parameters, based on fatigue crack growth data of Cr-Ni-Mo-V steel welded joints. Results showed that fatigue crack growth curves provided by the FKM or WES were good choice when few inputs were at hand while the curves in the BS7910, JSME and ASME were recommended for precise estimation. It was indicated that the assessment of welded joints solely by fatigue crack growth behavior at base metal part and the assessment of fatigue crack growth for the aged condition by as-received one both resulted in non-conservativeness, albeit dependent on the range of stress ratios, R. A new bilinear form of fatigue crack growth model independent of R was developed based on transition point occurred in the near-threshold regime. This constituted the bilinear approach to fatigue assessment, and thus contributed to the optimization of fatigue assessment in the near-threshold regime.
A Static Analysis of Uplift During Strong Earthquakes of Unanchored Flat-Bottom Cylindrical Shell Tanks
Authors: Nakashima Teruhiro , Taniguchi Tomoyo
Published: December 2016

For analyzing the uplift displacement of the tank bottom plate statically and precisely, this paper develops a shell element, ring element and spring element partially attached to the ring element. These elements are defined as a semi-analytical finite element. Moreover in analyzing uplift of the tank bottom plate precisely, the ring element can deal with effects of the large deformation, while the spring element enables to express the partial contact between the tank bottom plate and foundation. Dead load, hydro-pressure and inertia force due to earthquakes acceleration as well as dynamic pressure of fluid induced by bulging and rocking motions of the tank are applied statically. Comparison of results by the proposed method and that computed by the explicit FE Analysis reveals that the accurate uplift displacement is not obtained until all physical conditions involved in the tank rocking motion and the inward deformation of the tank shell is properly considered.
The NeT Task Group 6 Weld Residual Stress Measurement and Simulation Round Robin in Alloy 600/82
Authors: Smith Mike C. , Muransky Ondrej , Akrivos Vasileios , Angles Jean
Published: December 2016

The mission of the NeT European collaborative network is to develop experimental and numerical techniques and standards for the reliable characterisation of residual stresses in structural welds. NeT achieves this by conducting parallel measurement and prediction round robins on closely controlled and well characterised benchmark weldments. NeT TG6 follows on from the successful TG1 and TG4 benchmarks, which both examined welds in AISI 316L material. NeT TG6 examines an Alloy 600 plate containing a three pass “slot” weld made with Alloy 82 consumables. This paper describes the NeT TG6 project as a whole, and presents preliminary materials characterisation, residual stress measurement, and residual stress modelling results.
Simulation of a Multi-Pass Dissimilar Metal Nozzle to Pipe Weld Using Abaqus 2D Weld GUI and Comparison With Measurements
Authors: Parmar Chandrahas , Gill Christopher , Pellereau Benjamin , Hurrell Paul
Published: December 2016

The computer simulation of multiple layering of welds is necessary to determine the distortion and residual stresses arising from the welding process. The welding simulation requires thermal and structural solutions, which are usually carried out in two simulations. Once solved, the thermal transient model temperature results are read in to the structural model to solve for component stresses.

This paper describes the application of the Abaqus Weld Interface (AWI) plug-in for 2D axisymmetric simulation of the residual stresses generated in a Dissimilar Metal Weld (DMW) nozzle to pipe joint comprising of an Alloy 600 nozzle girth weld to a 316 LN Stainless Steel (SS) safe-end pipe. The test piece was manufactured for an ongoing programme within Rolls-Royce PLC. A mechanised Tungsten Inert Gas (TIG) welding process was employed depositing 83 weld bead passes. The weld filler material was Alloy 82.

The AWI Graphical User Interface (GUI) simplifies and saves a large amount of time towards generating the Finite Element Models (FEMs). By using the AWI plug-in within Abaqus/CAE, the FEMs take approximately a month to generate and solve with significant time savings associated with setting up the surfaces for the welding bead sequences and matching the heat input to the actual specimen. The GUI rapidly creates both the thermal and structural input files for the Abaqus/Standard solver. However, modifications were made to the thermal and structural FEM model input files to suit the analysis pre-processing requirements for idealised conditions to match the test piece pipework conditions.

FEM predictions captured the characteristic through-wall Weld Residual Stress (WRS) profiles measured by Deep Hole Drilling (DHD). The weld shrinkage was under estimated.
Stress Evaluation Method of Baffle Former Bolt and its Maintenance Program
Authors: Matsubara Toru , Mogami Yuichi
Published: December 2016

Baffle Former Bolt (BFB) is a fastening part of Reactor Vessel Internals (RVI) of PWR. BFB is made of type 347 or 316CW (cold work) stainless steel and it is known to have the risk of cracking caused by Irradiation Assisted Stress Corrosion Cracking (IASCC) under high neutron flux and tensile stress. To evaluate the time to crack of BFB, BFB’s time-dependent stress change caused by irradiation creep (relaxation) and by the swelling deformation of a baffle structure should be obtained. The authors have developed the finite element (FE) analysis method to calculate time-dependent stress of BFB considering the irradiation effects. The method combines two kinds of models; “global model” to calculate the deformation of whole baffle structure and “local model” to calculate the peak stress at the stress concentrated area under the bolt head. Incorporating the above calculation method, a new BFB inspection and evaluation guideline has been established in Japan. The concept of the guideline is also outlined in the paper.
Factors Affecting Cyclic Performance of Tempered Martensitic Steels
Authors: Parker Jonathan
Published: December 2016

The efficiency of thermal power plants is related to operating steam pressure and temperature. In many countries the need to maximize performance and minimize emissions, provide an incentive to build new power plants. Improvements to design offer important benefits for these generating stations. An enabling technology to greater efficiency is also the development and use of engineering materials with superior properties. The new steels and other alloys offer significant advantages when plants must operate in ‘flexible’ mode. The greater material strength permits components to be made with lower wall thickness. However, it is important that the higher strength is not achieved at the expense of ductility since poor creep ductility is known to be one factor linked to ‘burst’ type fractures. This paper outlines EPRI collaborative work associated with the fabrication and operation of tempered martensitic steel components used in advanced power plant.
Numerical and Experimental Studies of Pipe Vibration Generated by Elongated Orifice
Authors: Bai Wenjie , Duan Quan , Zhang Zaoxiao
Published: December 2016

Hydraulic tests for elongated orifice-induced wall pressure fluctuations and vibration in pipeline have been carried out. The regulating modes of test system consist of maintaining outlet pressure to increase flow rate and maintaining flow rate to decrease outlet pressure. Both regulating modes would increase the possibility of cavitation within elongated orifice, which has been confirmed by numerical simulation in present study. Statistical characteristics of the fluctuating pressure and structure vibration response have been studied. The standard deviation analyses indicate that the amplitude of fluctuating pressure is mainly determined by flow rate. The power spectral density analyses show that the energy of the fluctuating pressure behind elongated orifice is concentrated in lower frequency range and it can be divided into two parts in this test: the pressure pulsation excited by plunger pump and the random fluctuating pressure produced by elongated orifice’s disturbance. The power spectral density of pipe vibration response shows that the lower frequency of pipe vibration response can be ascribed to the fluctuating pressure behind elongated orifice and the characteristic frequencies corresponding to cavitation within elongated orifice are in the higher frequency range.
Finite Element Simulation and Experimental Investigation of Welding Residual Stress for PWR Safe-End
Authors: Zhang Guodong , Xue Fei , Zhao Yanfen , Zhang Lu
Published: December 2016

A 3-D sequential coupling finite element simulation is performed to investigate the temperature field and residual stress in the dissimilar metal weld of a PWR safe-end and nozzle. Chemical compositions and welding residual stress of the dissimilar metal weld are measured. And residual stress of the welded joint of nozzle and safe-end has been studied, aiming to provide a reference for the fabrication and operation of safe-end and nozzle. The testing results show that the experiment results are consistent with FE results. The FE simulation method can be used for the welding residual analysis of the welded joint. And, the calculating results show that large hoop (S33) and axial (S22) of welding residual stresses are generated in the weld metal. The maximum tensile and compressive stresses of S22 and S33 are all in the weld metal or at the interface of the nozzle and weld metal. Due to the difference in mechanical properties and chemical compositions between the base metal and weld metal, a discontinuous stress distribution is generated across the interface between the weld metal and nozzle.
Shaking Table Tests of a Piping System With Viscoelastic Dampers Subjected to Severe Earthquake Motions
Authors: Kostarev Victor , Tamura Ichiro , Kuramasu Masashi , Barutzki Frank , Vasilev Petr , Enomoto Yuji , Namita Yoshio , Okita Shunsuke , Sato Yuki
Published: December 2016

In Shimane Nuclear Power Plant of the Chugoku Electric Power Co. located in the West Japan area, a number of safety improvements are planned to be implemented aiming at achieving the highest world level in nuclear safety. One of the new safety approaches for seismic protection of NPPs is the application of viscoelastic dampers for safety related piping, systems and components. This technology is widely spread in nuclear power since 80s of the last century, [1 and 2]. In order to investigate and check the actual behavior of viscoelastic dampers installed at piping systems and subjected to severe earthquake motions, a shaking table test with full-scale piping and viscoelastic dampers was carried out. The shaking table test was performed for two general conditions. One is without aseismic devices and the other one is with viscoelastic dampers. It was confirmed by comparing the test results of the above mentioned two conditions that viscoelastic dampers provide to piping systems very high overall damping and protect piping systems even against large earthquakes.
Validation of Weight Function Based Process-Zone Model for Evaluation of Delayed Hydride Cracking Initiation in Zr-2.5Nb Pressure Tubes
Authors: Xu Steven X. , Kawa Dennis , Cui Jun , Chaput Heather
Published: December 2016

In-service flaws in cold-worked Zr-2.5 Nb pressure tubes in CANDU(1) reactors are susceptible to a phenomenon known as delayed hydride cracking (DHC). The material is susceptible to DHC when there is diffusion of hydrogen atoms to a service-induced flaw, precipitation of hydrides on appropriately oriented crystallographic planes in the zirconium alloy matrix material, and development of a hydrided region at the flaw tip. The hydrided region could then fracture to the extent that a crack forms and DHC is said to have initiated. Examples of in-service flaws are fuel bundle scratches, crevice corrosion marks, fuel bundle bearing pad fretting flaws, and debris fretting flaws. These flaws are volumetric in nature. Evaluation of DHC initiation from the flaw is a requirement of Canadian Standards Association (CSA) Standard N285.8. This paper describes the validation of the weight function based process-zone model for evaluation of pressure tube flaws for DHC initiation. Validation was performed by comparing the predicted threshold load levels for DHC initiation with the results from DHC initiation experiments on small notched specimens. The notches in the specimens simulate axial in-service flaws in the pressure tube. The validation was performed for both un-irradiated and pre-irradiated pressure tube material.
How will induced seismicity in Oklahoma respond to decreased saltwater injection rates?
Authors: Langenbruch Cornelius , Zoback Mark D.
Published: December 2016

Earthquake rates in Oklahoma should significantly decrease by the end of 2016 and approach historic levels within the next years.
Retracing embryological fate
Authors: Behjati Sam
Published: December 2016

Cloned organoids derived from adult mice enable reconstruction of embryonic lineages
Can T cells be too exhausted to fight back?
Authors: Turner Stephen J. , Russ Brendan E.
Published: December 2016

The transcriptional network becomes less malleable in persistently activated T cells
Metabolic cues for hematopoietic stem cells
Authors: Sommerkamp Pia , Trumpp Andreas
Published: December 2016

Manipulating mitophagy and dietary valine may lead to stem cell therapies
Performance Evaluation of Allplex Respiratory Panels 1, 2, and 3 for Detection of Respiratory Viruses and Influenza A Virus Subtypes
Authors: Huh Hee Jae , Kim Ji-Youn , Kwon Hyeon Jeong , Yun Sun Ae , Lee Myoung-Keun , Lee Nam Yong , Kim Jong-Won , Ki Chang-Seok
Published: December 2016

The Allplex respiratory panels 1, 2, and 3 (Allplex) comprise a one-step real-time reverse transcription-PCR assay for the detection of respiratory viruses (RVs) and influenza A subtypes based on multiple detection temperature (MuDT) technology. The performance of the Allplex assay was compared with those of the AdvanSure RV real-time PCR kit (AdvanSure) and the PowerChek pandemic H1N1/H3N2/H5N1 real-time PCR kit (PowerChek) using 417 clinical respiratory specimens. In comparison with the AdvanSure assay for RV detection by each virus, the ranges of positive percent agreement, negative percent agreement, and kappa values with the Allplex assay were 82.8 to 100%, 95.5 to 100%, and 0.85 to 1.00, respectively. For influenza A virus (INF A) subtyping, the kappa values between the Allplex and PowerChek assays were 0.67 and 1.00 for the INF A H1N1-pdm09 and H3 subtypes, respectively. Uniplex PCR and sequencing for samples with discrepant results demonstrated that the majority of results were concordant with those from the Allplex assay. When testing 24 samples, the turnaround and hands-on time required to perform the Allplex assay were 4 h 15 min and 15 min, respectively. In conclusion, the Allplex assay produced results comparable to those from the AdvanSure and PowerChek assays.
Structural Protein VP2 of African Horse Sickness Virus Is Not Essential for Virus Replication
In Vitro
Authors: van Gennip René G. P. , van de Water Sandra G. P. , Potgieter Christiaan A. , van Rijn Piet A.
Published: December 2016

The
Reoviridae
family consists of nonenveloped multilayered viruses with a double-stranded RNA genome consisting of 9 to 12 genome segments. The
Orbivirus
genus of the
Reoviridae
family contains African horse sickness virus (AHSV), bluetongue virus, and epizootic hemorrhagic disease virus, which cause notifiable diseases and are spread by biting
Culicoides
species. Here, we used reverse genetics for AHSV to study the role of outer capsid protein VP2, encoded by genome segment 2 (Seg-2). Expansion of a previously found deletion in Seg-2 indicates that structural protein VP2 of AHSV is not essential for virus replication
in vitro
. In addition, in-frame replacement of RNA sequences in Seg-2 by that of green fluorescence protein (GFP) resulted in AHSV expressing GFP, which further confirmed that VP2 is not essential for virus replication. In contrast to virus replication without VP2 expression in mammalian cells, virus replication in insect cells was strongly reduced, and virus release from insect cells was completely abolished. Further, the other outer capsid protein, VP5, was not copurified with virions for virus mutants without VP2 expression. AHSV without VP5 expression, however, could not be recovered, indicating that outer capsid protein VP5 is essential for virus replication
in vitro
. Our results demonstrate for the first time that a structural viral protein is not essential for orbivirus replication
in vitro
, which opens new possibilities for research on other members of the
Reoviridae
family.

IMPORTANCE
Members of the
Reoviridae
family cause major health problems worldwide, ranging from lethal diarrhea caused by rotavirus in humans to economic losses in livestock production caused by different orbiviruses. The
Orbivirus
genus contains many virus species, of which bluetongue virus, epizootic hemorrhagic disease virus, and African horse sickness virus (AHSV) cause notifiable diseases according to the World Organization of Animal Health. Recently, it has been shown that nonstructural proteins NS3/NS3a and NS4 are not essential for virus replication
in vitro
, whereas it is generally assumed that structural proteins VP1 to -7 of these nonenveloped, architecturally complex virus particles are essential. Here we demonstrate for the first time that structural protein VP2 of AHSV is not essential for virus replication
in vitro
. Our findings are very important for virologists working in the field of nonenveloped viruses, in particular reoviruses.
Importance of diagnostic work-up of Guillain-Barré syndrome in pregnancy
Authors: Pollak-Christian Elza , Lee Kyong-Soon
Published: December 2016

We report a full-term neonate presenting with symptomatic congenital cytomegalovirus (CMV) infection with hepatosplenomegaly, ‘blueberry muffin’ rash, intracranial calcifications, thrombocytopenia and respiratory distress. Maternal history was relevant for Guillain-Barré syndrome (GBS) during the first trimester of pregnancy. CMV infection is an important cause of GBS; thus, women presenting GBS during pregnancy should be screened for CMV infection. If positive, they may benefit from specialised monitoring and treatment in the antenatal period, which may decrease the risk of major neurodevelopmental sequelae of congenital CMV in the neonate.
Assessment of cardiovascular risk in Tunisia: applying the Framingham risk score to national survey data
Authors: Saidi O , Malouche D , O'Flaherty M , Ben Mansour N , A Skhiri H , Ben Romdhane H , Bezdah L
Published: December 2016

Objective

This paper aims to assess the socioeconomic determinants of a high 10 year cardiovascular risk in Tunisia.

Setting

We used a national population based cross sectional survey conducted in 2005 in Tunisia comprising 7780 subjects. We applied the non-laboratory version of the Framingham equation to estimate the 10 year cardiovascular risk.

Participants

8007 participants, aged 35–74 years, were included in the sample but effective exclusion of individuals with cardiovascular diseases and cancer resulted in 7780 subjects (3326 men and 4454 women) included in the analysis.

Results

Mean age was 48.7 years. Women accounted for 50.5% of participants. According to the Framingham equation, 18.1% (17.25–18.9%) of the study population had a high risk (≥20% within 10 years). The gender difference was striking and statistically significant: 27.2% (25.7–28.7%) of men had a high risk, threefold higher than women (9.7%; 8.8–10.5%). A higher 10 year global cardiovascular risk was associated with social disadvantage in men and women; thus illiterate and divorced individuals, and adults without a professional activity had a significantly higher risk of developing a cardiovascular event in 10 years. Illiterate men were at higher risk than those with secondary and higher education (OR=7.01; 5.49 to 9.14). The risk in illiterate women was more elevated (OR=13.57; 7.58 to 24.31). Those living in an urban area had a higher risk (OR=1.45 (1.19 to 1.76) in men and OR=1.71 (1.35 to 2.18) in women).

Conclusions

The 10 year global cardiovascular risk in the Tunisian population is already substantially high, affecting almost a third of men and 1 in 10 women, and concentrated in those more socially disadvantaged.
Validated adherence scales used in a measurement-guided medication management approach to target and tailor a medication adherence intervention: a randomised controlled trial
Authors: Nguyen Thi-My-Uyen , La Caze Adam , Cottrell Neil
Published: December 2016

Objective

To determine if a targeted and tailored intervention based on a discussion informed by validated adherence scales will improve medication adherence.

Design

Prospective randomised trial.

Setting

2 community pharmacies in Brisbane, Australia.

Methods

Patients recently initiated on a cardiovascular or oral hypoglycaemic medication within the past 4–12 weeks were recruited from two community pharmacies. Participants identified as non-adherent using the Medication Adherence Questionnaire (MAQ) were randomised into the intervention or control group. The intervention group received a tailored intervention based on a discussion informed by responses to the MAQ, Beliefs about Medicines Questionnaire-Specific and Brief Illness Perception Questionnaire. Adherence was measured using the MAQ at 3 and 6 months following the intervention.

Results

A total of 408 patients were assessed for eligibility, from which 152 participants were enrolled into the study. 120 participants were identified as non-adherent using the MAQ and randomised to the ‘intervention’ or ‘control’ group. The mean MAQ score at baseline in the intervention and control were similar (1.58: 95% CI (1.38 to 1.78) and 1.60: 95% CI (1.43 to 1.77), respectively). There was a statistically significant improvement in adherence in the intervention group compared to control at 3 months (mean MAQ score 0.42: 95% CI (0.27 to 0.57) vs 1.58: 95% CI (1.42 to 1.75); p<0.001). The significant improvement in MAQ score in the intervention group compared to control was sustained at 6 months (0.48: 95% CI (0.31 to 0.65) vs 1.48: 95% CI (1.27 to 1.69); p<0.001).

Conclusions

An intervention that targeted non-adherent participants and tailored to participant-specific reasons for non-adherence was successful at improving medication adherence.

Trial registration number

ACTRN12613000162718; Results.
Enhancing learning experiences
Authors: Hall Elaine
Published: December 2016

Equine thermographer Elaine Hall wanted to improve her teaching skills so she enrolled on a course that could equip her with the skills she needed to improve her students' learning experience
Experimental analysis of large-scale pullout tests conducted on polyester anchored geogrid reinforcement systems
Authors: Sadat Taghavi S.H. , Mosallanezhad M.
Published: December 2016

The pullout resistance of reinforcement, such as geogrids in mechanically stabilized earth (MSE) walls, includes the skin friction between the soil and solid geogrid surfaces. It also includes the bearing resistance against the transverse ribs, which has a greater influence on the production of pullout resistance. Taking the current limitations involved in producing woven polyester geogrids into consideration (i.e., the limited thickness of the transverse ribs), the amount of bearing resistance developed in front of transverse ribs is limited in the pullout mechanism. Thus, along with introducing an innovative and applied system, this research has endeavoured to demonstrate the effective performance of this new system in increasing the passive resistance — and thereby the pullout resistance — of standard geogrids. This new system, which is formed by adding steel transverse elements (a set of steel equal angles) to the ordinary polyester geogrids by means of nuts and bolts, is called an anchored geogrid (AG). The experimental results show that a spacing-to-height ratio of transversal elements equal to 5 gives the maximum pullout resistance for a polyester AG system in sandy soil used in the study. With an optimum arrangement, this system is capable of increasing the pullout resistance of the ordinary geogrid system by 65%. In addition, based on the plasticity solution, the pullout bearing failure mechanisms of a single isolated transverse element in the polyester AG system depend on overburden pressures.
Ground-layer composition affects tree fine root biomass and soil nutrient availability in jack pine and black spruce forests under extreme drainage conditions
Authors: Pacé Marine , Fenton Nicole J. , Paré David , Bergeron Yves
Published: December 2016

In the boreal forest, long-lasting canopy gaps are associated with lichens on dry sites and with Sphagnum spp. on wet sites. We hypothesize that ground-layer composition plays a role in maintaining gaps through its effects on fine root biomass (diameter ≤ 2 mm) and soil nutrient availability. Along gradients of canopy openness in both jack pine (Pinus banksiana Lamb.) – lichen and black spruce (Picea mariana (Mill.) B.S.P.) – moss forests, the relationships between canopy closure, ground-layer composition, tree fine root biomass, and soil nutrients were analyzed and decomposed using path analysis. The effects of lichen and Sphagnum spp. removal on tree fine root biomass and soil nutrients were tested in situ. Although variations in pine fine root biomass were mainly explained by stand aboveground biomass, lichen removal locally increased fine root biomass by more than 50%, resin extractable soil potassium by 580%, and base cations by 180%. While Sphagnum cover was identified as a key driver of stand aboveground biomass reduction in paludified forest sites, its removal had no short-term effects on spruce fine root biomass and soil nutrients. Our results suggest that lichens, more than Sphagnum spp., affect tree growth via direct effects on soil nutrients. These two different patterns call for different silvicultural solutions to maintain productive stands.
The efficiency of poststratification compared with model-assisted estimation
Authors: Myllymäki Mari , Gobakken Terje , Næsset Erik , Kangas Annika
Published: December 2016

Survey sampling with model-assisted estimation has recently gained popularity in forest inventory. Another option for utilizing the auxiliary information is to use poststratification, which is a special case of model-assisted estimation with class variables as explanatory variables. In this study, we compared the efficiency of poststratification with an increasing number of strata with model-assisted estimation. We carried out a study based on a simulated population. We considered four different types of poststratifications, namely (i) stratification based on predictions of a linear model, (ii) stratification based on a regression tree model, (iii) stratification based on the first principal component of the explanatory variables, and (iv) stratification based on the regression tree model with the first principal component as the only explanatory variable. Furthermore, we examined both the traditional poststratification mean and variance estimators and the difference estimator and its variance estimator for poststratification. Within the recommended range of number of strata, the model-assisted approach was more efficient than poststratification. With a large number of strata, poststratification produced smaller standard error of estimates, but problems such as empty strata were encountered with small sample sizes. Using the first principal component directly for stratification or as an explanatory variable was the most efficient approach.
The Banks–Zaks expansion in perturbative QCD: An update
Authors: Stevenson P. M.
Published: December 2016

The recent QCD calculations of the five-loop [Formula: see text]-function and of [Formula: see text] to [Formula: see text] provide one more term in the Banks–Zaks (BZ) expansion in [Formula: see text]. There is no longer any hope that the expansion could extend, even crudely, to low [Formula: see text]. Above [Formula: see text], however, the results appear to be reasonably consistent from order to order.
An Approach Based on Definite Integrals to Multi-Criteria Decision Making with Correlative Intuitionistic Fuzzy Information
Authors: Yu Shan , Xu Zeshui
Published: December 2016

Integration plays a very important role in the fusion methods. In this paper, we put forward the subtraction and division definite integrals based on the fuzzy measure and the admissible order for aggregating not only discrete but also continuous correlative intuitionistic fuzzy information. These definite integrals are implemented by constructing the integrands and the integral limits respectively, and based on which an approach to multi-criteria decision making with correlative intuitionistic fuzzy information is developed. Finally, an illustrative example involving technology improvement of Midwest American Manufacturing Corp is employed to verify the practicality and effectiveness of our approach.
On a Relationship Between Fuzzy Measures and AIFS
Authors: Torra VicenÇ , Narukawa Yasuo , Yager Ronald R.
Published: December 2016

The literature discusses several extensions of fuzzy sets. AIFS, IVFS, HFS, type-2 fuzzy sets are some of them. Interval valued fuzzy sets is one of the extensions where the membership is not a single value but an interval. Atanassov Intuitionistic fuzzy sets, for short AIFS, are defined in terms of two values for each element: membership and non-membership. In this paper we discuss AIFS and their relationship with fuzzy measures. The discussion permits us to define counter AIFS (cIFS) and discretionary AIFS (dIFS). They are extensions of fuzzy sets that are based on fuzzy measures.
Representability of Fuzzy Biorders and Fuzzy Weak Orders
Authors: Mishra Seema , Srivastava Rekha
Published: December 2016

In this paper, we have studied representability of both fuzzy biorders and fuzzy weak orders. It has also been shown that union of a finite family of fuzzy weak orders with respect to a t-norm T is a fuzzy quasi-transitive relation with respect to T. In the last theorem, we have obtained a characterization for a TL-representable fuzzy weak order.
Privacy Protection in Outsourced Spatial Databases
Authors: Kamel Ibrahim , Ba-Hutair Mohammed N.
Published: December 2016

Organizations have come to realize that storing their databases in the Cloud rather than in-house data centers is cheaper and more flexible. However, companies are still concerned about the privacy and the security of their data. Encrypting the whole database before uploading it to the Cloud solves the security issue. But querying the database requires downloading and decrypting the entire dataset, which is impractical.

This paper proposes a new scheme for protecting the privacy and integrity of spatial data stored in the Cloud while being able to execute range queries efficiently. Data objects are encrypted and sorted using Z-order space-filling curve. An index is built on top of the encrypted data to be utilized by the Service Provider to identify and retrieve a superset of data objects that contains the answers to the query. Many simulation experiments have been carried out to measure the performance of the proposed scheme in terms of the redundancy in data retrieved. The experimental results show that the proposed scheme outperforms the most recent scheme by Kim et al. in terms of data redundancy.
(Mis)managing parallel computing research through EU project funding
Authors: Träff Jesper Larsson
Published: December 2016

Considering the possible negative long-term effects of EU projects on European scientific culture.
Creating connection with autonomous facial animation
Authors: Sagar Mark , Seymour Mike , Henderson Annette
Published: December 2016

Biologically based computational modeling promises virtual characters capable of face-to-face human interaction.