bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessment of Constraint Effects on the Local Behaviour of a Propagating Crack Under Cyclic Loading
Authors: Goldthorpe M. R. , Sherry A. H. 
Published: August 2013

During operation, reactor components experience a range of static and cyclic loading that have the potential to result in environmental-fatigue crack initiation and growth. Recent experimental work has indicated that the ASME XI fatigue ‘in air’ design curves are non-conservative for fatigue cracks propagating in primary water environments at fixed temperatures of relevance to the plant. The approach adopted to assess these tests has, to date, followed current best practice: in which global Linear Elastic Fracture Mechanics (LEFM) loading parameters are used to quantify crack growth rates.
To help establish an improved understanding of these data, and to assist in their application to assess plant components, a local crack-tip finite element model has been developed. The model incorporates material constitutive behavior that simulates cyclic deformation of austenitic steel, can take account of plasticity-induced crack closure and can take into consideration cracks in structurally-representative geometries via the T-stress constraint parameter.
The results of studies using the model suggest that highly compressive values of the T-stress constraint parameter tend to promote less severe reverse loading of the crack tip compared with high constraint geometries such as pre-cracked compact tension and bend test specimens. These findings indicate that rates of corrosion-fatigue in actual structural geometries might be different from those observed in pre-cracked test specimens.
Fracture Toughness Evaluation in C(T) Specimens With Reduced Out-of-Plane Constraint
Authors: Kulka R. S. , Sherry A. H. 
Published: August 2013

During fracture toughness testing of C(T) specimens, an important assumption is that the test specimen is highly constrained. This is ensured by testing a deeply cracked specimen, with in-plane and out-of-plane dimensions that are sufficient to guarantee an appropriate level of crack tip stress triaxiality. This condition guarantees that high-constraint fracture toughness values are derived, conservative for use in standard fracture mechanics assessments.
In reality, many components have small out-of-plane dimensions (small thicknesses). This often causes a reduction in crack tip constraint of a sufficient amount to increase the effective fracture toughness of the components. However, there is currently limited understanding as to the magnitude of the benefits that could be claimed from out-of-plane constraint loss.
Finite element and damage modelling of thin C(T) specimens under different loading conditions has been undertaken, looking at the effects of loss of out-of-plane constraint, to help validate the results of an on-going testing programme. When available, data from testing of thin C(T) specimens could allow the parameters of the damage model, based upon a ductile criterion, to be calibrated. Material resistance to fracture under different situations has been determined, leading to a correlation of toughness to the constraint condition for a nominal set of material parameters.
Evaluating the Effect of Nozzle Weld Stiffness When Using Shell Finite Element Models for ASME Code Evaluations
Authors: Dunlap Bryan , Ziada Hassan , Julyk John 
Published: August 2013

Typically the use of SHELL finite elements to model nozzle/vessel interfaces will not include details of the weld at the interface. The omission of the weld details from SHELL element models is due to the difficulty in implementing such details and the assumption that additional interface stiffness due to the weld will have a negligible effect on results at locations of interest for Code evaluation. This study will demonstrate a proposed method for modeling weld details with SHELL elements and then evaluate the magnitude of the weld stiffness effect on results and Code compliance.
The method of modeling the weld details with SHELL elements used in this study will follow the guidance provided by ASME BPVC Section VIII, Division 2, Annex 5.A [2] for such interfaces. Models of nozzle/vessel interfaces will be shown comparing results of SOLID element models with and without the weld detail, and then SHELL element models both with and without the weld detail. The results from these models will be evaluated and recommendations for future modeling and evaluation of nozzle/shell interfaces with SHELL elements will be offered.
Probabilistic Estimation of Flow-Accelerated Corrosion Rate at the Welded Joints of the Nuclear Piping System
Authors: Lu Dongliang , Pandey M. D. , Jyrkama M. I. 
Published: August 2013

Feeder piping is an integral part of the heat transport system (HTS) that supplies the primary coolant from the reactor to the steam generator in CANDU reactors. One of the life limiting factors of the feeder pipes is the highly localized wall thinning caused by the flow-accelerated corrosion (FAC) at the welded joints of the pipes. To ensure the fitness-for-service of the piping system, periodic inspections of the pipe wall thickness and estimation of the FAC thinning rate at the welded joints are needed.
A major challenge of FAC rate estimation at the welded joints is that the initial wall thickness is known precisely, since the grinding process before the welding introduces initial thinning in the pipes. Using the nominal wall thickness without considering this initial thinning is likely to overestimate the FAC rate. Another difficult is the sizing error in the wall thickness measurements, which also needs to be properly accounted.
This paper develops a sound probabilistic method for the FAC estimation for the welded joints considering both the initial thinning and sizing error. Predictions regarding the lifetime of individual welded joints are also obtained from the proposed method. A practical case study of the problem in a nuclear plant is presented.
Applicability of Semi-Analytical Finite Elements for Analyzing Uplift Displacement of Flat-Bottom Cylindrical Shell Tanks Statically
Authors: Nakashima Teruhiro , Taniguchi Tomoyo 
Published: August 2013

The rocking motion of tanks due to earthquakes causes the uplift and partial deformation of the tank bottom plate that has been considered to contribute to damage of various tanks.
For analyzing the uplift displacement of the tank bottom plate numerically and precisely, this paper develops the analytical finite shell element, ring element and spring element partially attached to the ring element. These elements are defined as semi-analytical finite element models. Fourier series give their circumferential displacement function, while polynomial gives their radial displacement function.
Applicability of a set of these elements to analyze the shell deformation and contact between the tank bottom plate and the foundation subjected to ground acceleration induced loads is verified. For evaluating analytical accuracy of the proposed method, numerical results are compared with other numerical ones.
Development of Ultrasonic Phased Array Inspection of Polyethylene Pipe Joints
Authors: Troughton Mike , Spicer Malcolm , Hagglund Fredrik 
Published: August 2013

The current practice for assuring the quality of butt fusion joints in polyethylene (PE) pipes during installation is by recording the welding parameters used, together with a visual inspection of the welded joint, supplemented by the destructive testing of welds on a sample basis using a short-term test. However, visual inspection can only examine the external surface of the pipe weld; it cannot provide evidence of embedded flaws or a weld with incomplete fusion or cold fusion. In addition, cutting a specimen from a weld for mechanical testing and then replacing it with a weld of unknown quality does not ensure the integrity of the pipeline. Volumetric non-destructive examination (NDE) will not destroy perfectly good welds and has the added environmental advantage of reduced waste.
This paper describes an ongoing European-funded project to develop ultrasonic phased array techniques for the inspection of butt fusion (BF) and electrofusion (EF) joints in PE pipes of diameters between 90 and 1000mm, and to determine critical defect sizes and particulate contamination levels using accelerated long-term testing. In addition, defect recognition and automated defect sentencing software will be developed to allow the system to automatically sentence detected flaws.
Frequency response and distortion properties of nonlinear image processing algorithms and the importance of imaging context
Authors: Wells Jered R. , Dobbins James T. 
Published: August 2013

Purpose:The most common metrics for resolution analysis in medical imaging are valid only for (approximately) linear systems. While analogues to these metrics have been used in attempts to describe resolution performance in nonlinear systems, the analysis is incomplete since distortion effects are often ignored. The authors have developed a methodology to analyze the amplitude modulation and waveform distortion properties of nonlinear systems with specific application to medical image processing algorithms.Methods:Using sinusoidal basis functions, two metrics were derived which distinguish amplitude modulation from nonlinear waveform distortion: principle frequency response and distortion power spectrum, respectively. Additionally, two figures of merit were developed to describe the relative impact of nonlinear distortion as a result of image processing: distortion index (DI) and ΣDI. Three nonlinear denoising algorithms, the median, bilateral, and wavelet denoising filters, were selected as example functions to demonstrate the utility of the metrics derived in this study.Results:Each filter showed very different resolution and waveform distortion properties. In particular, the amplitude and extent of nonlinear distortion depended strongly on image context and the type of nonlinear mechanism employed. Nonlinear waveform distortion constituted up to 30% of the median filter output signal power in high contrast‐to‐noise ratio (CNR) scenarios. Conversely, nonlinear distortion never exceeded 1% of the bilateral filter output signal power. The wavelet denoising response contained between 1% and 9% distortion which varied weakly as a function of CNR.Conclusions:The analytical metrics described in the paper demonstrate the importance of considering both resolution‐ and distortion‐related effects in characterizing the performance of nonlinear imaging systems with specific application to image processing algorithms. Findings with three common nonlinear algorithms demonstrate a range of CNR values over which it is important to consider the impact of the nonlinear nature of each algorithm. Background context is also shown to influence the degree to which the nonlinear nature of the algorithm influences resolution and distortion. While no single metric can yet anticipate observer performance in nonlinear systems, the approach described can demonstrate the range of imaging contexts over which such nonlinear effects are important to consider.
Octavius 4D characterization for flattened and flattening filter free rotational deliveries
Authors: McGarry Conor K. , O'Connell Barry F. , Grattan Mark W. D. , Agnew Christina E. , Irvine Denise M. , Hounsell Alan R. 
Published: August 2013

Purpose:In this study the Octavius detector 729 ionization chamber (IC) array with the Octavius 4D phantom was characterized for flattening filter (FF) and flattening filter free (FFF) static and rotational beams. The device was assessed for verification with FF and FFF RapidArc treatment plans.Methods:The response of the detectors to field size, dose linearity, and dose rate were assessed for 6 MV FF beams and also 6 and 10 MV FFF beams. Dosimetric and mechanical accuracy of the detector array within the Octavius 4D rotational phantom was evaluated against measurements made using semiflex and pinpoint ionization chambers, and radiochromic film. Verification FF and FFF RapidArc plans were assessed using a gamma function with 3%/3 mm tolerances and 2%/2 mm tolerances and further analysis of these plans was undertaken using film and a second detector array with higher spatial resolution.Results:A warm‐up dose of >6 Gy was required for detector stability. Dose‐rate measurements were stable across a range from 0.26 to 15 Gy/min and dose response was linear, although the device overestimated small doses compared with pinpoint ionization chamber measurements. Output factors agreed with ionization chamber measurements to within 0.6% for square fields of side between 3 and 25 cm and within 1.2% for 2 × 2 cm2 fields. The Octavius 4D phantom was found to be consistent with measurements made with radiochromic film, where the gantry angle was found to be within 0.4° of that expected during rotational deliveries. RapidArc FF and FFF beams were found to have an accuracy of >97.9% and >90% of pixels passing 3%/3 mm and 2%/2 mm, respectively. Detector spatial resolution was observed to be a factor in determining the accurate delivery of each plan, particularly at steep dose gradients. This was confirmed using data from a second detector array with higher spatial resolution and with radiochromic film.Conclusions:The Octavius 4D phantom with associated Octavius detector 729 ionization chamber array is a dosimetrically and mechanically stable device for pretreatment verification of FF and FFF RapidArc treatments. Further improvements may be possible through use of a detector array with higher spatial resolution (detector size and/or detector spacing).
Draft Genome Sequence of Helicobacter fennelliae Strain MRY12-0050, Isolated from a Bacteremia Patient
Authors: Rimbara Emiko , Matsui Mari , Mori Shigetarou , Suzuki Satowa , Suzuki Masato , Kim Hyun , Sekizuka Tsuyoshi , Kuroda Makoto , Shibayama Keigo 
Published: August 2013

ABSTRACT

Helicobacter fennelliae
, a human enterohepatic pathogen, causes bacteremia and colitis. We isolated
H. fennelliae
strain MRY12-0050 from a female patient; this strain was isolated from 2 other patients from the same hospital during the same period, suggesting human-to-human transmission. This is the first report of an
H. fennelliae
genome sequence.
Complete Genome Sequence of Tick-Borne Encephalitis Virus Strain A104 Isolated from a Yellow-Necked Mouse (
Apodemus flavicollis
) in Austria
Authors: Frey Stefan , Essbauer Sandra , Zöller Gudrun , Klempa Boris , Weidmann Manfred , Dobler Gerhard , Pfeffer Martin 
Published: August 2013

ABSTRACT
Tick-borne encephalitis virus (TBEV) strain A104 was isolated from the brain of a yellow-necked mouse in Austria in 1990. The complete genome sequence was 11,097 nucleotides long. Comparison with TBEV prototype strain Neudoerfl showed 32 amino acid exchanges and the absence of an internal poly(A) stretch within the 3′ noncoding region.
Complete Genome Sequence of a Variant of the Methicillin-Resistant Staphylococcus aureus ST239 Lineage, Strain BMB9393, Displaying Superior Ability To Accumulate
ica
-Independent Biofilm
Authors: Costa Maiana Oliveira Cerqueira , Beltrame Cristiana Ossaille , Ferreira Fabienne Antunes , Botelho Ana Maria Nunes , Lima Nicholas Costa Barroso , Souza Rangel Celso , de Almeida Luiz Gonzaga Paula , Vasconcelos Ana Tereza Ribeiro , Nicolás Marisa Fabiana , Figueiredo Agnes Marie Sá 
Published: August 2013

ABSTRACT

Biofilm is considered an important virulence factor in nosocomial infections. Herein, we report the complete genome sequence of a variant of methicillin-resistant
Staphylococcus aureus
, strain BMB9393, which is highly disseminated in Brazil. This strain belongs to the lineage ST239 and displays increased ability to accumulate
ica
-independent biofilm and to invade human epithelial cells.
Genome Sequence of Klebsiella pneumoniae Strain ATCC 25955, an Oxygen-Insensitive Producer of 1,3-Propanediol
Authors: Wang Yu , Tao Fei , Li Chao , Li Lixiang , Xu Ping 
Published: August 2013

ABSTRACT

Klebsiella pneumoniae
strain ATCC 25955 is a 1,3-propanediol-producing bacterium that is insensitive to oxygen. Here, we present a 5.29-Mb assembly of its genome sequence. We have annotated 10 coding sequences (CDSs) for 1,3-propanediol fermentation and 18 CDSs for glycerol uptake. The CDSs related to virulence and by-product formation were also annotated.
Junonia coenia
Densovirus (JcDNV) Genome Structure
Authors: Pham Hanh T. , Huynh Oanh T. H. , Jousset Françoise-Xavière , Bergoin Max , Tijssen Peter 
Published: August 2013

ABSTRACT

The sequence of
Junonia coenia
densovirus was the first densovirus genome sequence published, but the first published sequence contained incomplete inverted terminal repeats and ambiguous nucleotides or indels leading to an incorrect map of the open reading frames. Our sequencing of clones of the complete genome demonstrated that this virus is closely related to other viruses in the
Densovirus
genus.
Genome Sequence of the 2,4,5-Trichlorophenoxyacetate-Degrading Bacterium Burkholderia phenoliruptrix Strain AC1100
Authors: Xu Ping , Yu Hao , Chakrabarty Ananda M. , Xun Luying 
Published: August 2013

ABSTRACT

Burkholderia phenoliruptrix
strain AC1100 (ATCC 53867) degrades a variety of recalcitrant xenobiotics, including 2,4,5-trichlorophenoxyacetate. The molecular mechanism of 2,4,5-trichlorophenoxyacetate degradation has been extensively studied. Here we present a 7.8-Mb assembly of the genome sequence of this 2,4,5-trichlorophenoxyacetate-degrading strain, which may provide useful information related to the degradation of chlorinated aromatic compounds.
Genome Sequence of the Cheese-Starter Strain Lactobacillus delbrueckii subsp.
lactis
CRL 581
Authors: Hebert Elvira María , Raya Raúl R. , Brown Lucía , Font de Valdez Graciela , Savoy de Giori Graciela , Taranto María Pía 
Published: August 2013

ABSTRACT

We report the genome sequence of
Lactobacillus delbrueckii
subsp.
lactis
CRL 581 (1,911,137 bp, GC 49.7%), a proteolytic strain isolated from a homemade Argentinian hard cheese which has a key role in bacterial nutrition and releases bioactive health-beneficial peptides from milk proteins.
Clinical and imaging services for TIA and minor stroke: results of two surveys of practice across the UK
Authors: Brazzelli Miriam , Shuler Kirsten , Quayyum Zahid , Hadley Donald , Muir Keith , McNamee Paul , De Wilde Janet , Dennis Martin , Sandercock Peter , Wardlaw Joanna M 
Published: August 2013

ObjectivesTransient ischaemic attack (TIA) is a medical emergency requiring rapid access to effective, organised, stroke prevention. There are about 90 000 TIAs per year in the UK. We assessed whether stroke-prevention services in the UK meet Government targets.DesignCross-sectional survey.SettingAll UK clinical and imaging stroke-prevention services.InterventionElectronic structured survey delivered over the web with automatic recording of responses into a database; reminders to non-respondents. The survey sought information on clinic frequency, staff, case-mix, details of brain and carotid artery imaging, medical and surgical treatments.Results114 stroke clinical and 146 imaging surveys were completed (both response rates 45%). Stroke-prevention services were available in most (97%) centres but only 31% operated 7 days/week. Half of the clinic referrals were TIA mimics, most patients (75%) were prescribed secondary prevention prior to clinic referral, and nurses performed the medical assessment in 28% of centres. CT was the most common and fastest first-line investigation; MR, used in 51% of centres, mostly after CT, was delayed up to 2 weeks in 26%; 51% of centres omitted blood-sensitive (GRE/T2*) MR sequences. Carotid imaging was with ultrasound in 95% of centres and 59% performed endarterectomy within 1 week of deciding to operate.ConclusionsStroke-prevention services are widely available in the UK. Delays to MRI, its use in addition to CT while omitting key sequences to diagnose haemorrhage, limit the potential benefit of MRI in stroke prevention, but inflate costs. Assessing TIA mimics requires clinical neurology expertise yet nurses run 28% of clinics. Further improvements are still required for optimal stroke prevention.
A mixed-methods study of the Care Needs of individuals with idiopathic Pulmonary fibrosis and their carers—CaNoPy: a study protocol
Authors: Byrne Anthony , Sampson Cathy , Baillie Jessica , Harrison Kim , Hope-Gill Ben , Hubbard Richard , Griffiths Gareth , Nelson Annmarie 
Published: August 2013

IntroductionIdiopathic pulmonary fibrosis (IPF) is a progressive, life-threatening illness of unknown aetiology, with no proven pharmacological treatments. There is a limited evidence base indicating that the disease negatively affects quality of life, leading to increased dependence, restrictions on daily activities and fatigue. However, there is a paucity of in-depth information on disease impact across its trajectory, particularly in relation to unmet needs, outcomes of importance to patients and the experiences of carers. Furthermore, little is known about the support and information needs of individuals and their carers, or at what point individual need should trigger a referral to palliative care services.Methods and analysisA mixed-methods study is proposed recruiting individuals with IPF at different stages of the disease and their carers from three respiratory centres in England and Wales. In-depth interviews will be undertaken with participants, adopting an Interpretative Phenomenological Analysis approach. The study will also use validated questionnaires to explore quality of life (EQ-5D), depression (Hospital Anxiety and Depression Scale), breathlessness (Borg dyspnoea scale) and cough (Leicester Cough Questionnaire, Cough Symptom Score).Ethics and disseminationEthical approvals were gained in April 2012. Palliative care research is a developing field, but there has been limited focus on IPF. We anticipate that the results of the study will enable healthcare professionals to provide appropriate palliative care across the trajectory for individuals with the disease, and their carers, and we therefore aim to disseminate via relevant respiratory and palliative care journals and conferences. We will also support the lay representative involved in the project to disseminate the findings to patient groups.
Healthcare utilisation and empowerment among women in Liberia
Authors: Sipsma Heather , Callands Tamora A , Bradley Elizabeth , Harris Benjamin , Johnson Billy , Hansen Nathan B 
Published: August 2013

BackgroundMany efforts have been undertaken to improve access to healthcare services in low-income settings; nevertheless, underutilisation persists. Women's lack of empowerment may be a central reason for underutilisation, but empirical literature establishing this relationship is sparse.MethodsWe conducted a cross-sectional study using data from the 2007 Liberia Demographic and Health Survey. Our sample included all non-pregnant women who were currently married or living with a partner (N=3925 unweighted). We used multivariate logistic regression to assess the associations between constructs derived from the Theory of Gender and Power (TGP) and healthcare utilisation.ResultsTwo-thirds of women (65.6%) had been to a healthcare facility for herself or her children in the past 12 months. Constructs from the three major theoretical structures were associated with healthcare utilisation. Women with no education, compared with women with some education, were less likely to have been to a healthcare facility (OR=0.76; 95% CI 0.62 to 0.93) as were women who had experienced sexual abuse (OR=0.65; 95% CI 0.45 to 0.95) and women who were married (OR=0.69, 95% CI 0.54 to 0.88). Women in higher wealth quintiles, compared with women in the next lower wealth quintile, and women with more decision-making power had greater odds of having been to a healthcare facility (OR=1.22; 95% CI 1.10 to 1.36 and OR=1.10; 95% CI 1.01 to 1.20; respectively).ConclusionsStrong associations exist between healthcare utilisation and empowerment among women in Liberia, and gender imbalances are prevalent. This fundamental issue likely needs to be addressed before large-scale improvement in health service utilisation can be expected.