bluuebunny/crossref_metadata_2025 huggingface dataset:
Establishing Corrosion Growth Rates Based on MFL-C vs. MFL In-Line Inspection Run-to-Run Comparisons
Authors: Graf Eric , Ellinger Matthew , Harper William , Bubenik Thomas , Hickey Stacy , Moreno Pamela
Published: December 2022

Performing in-line inspection (ILI) run-to-run comparisons is a vital component of any pipeline integrity management program. A primary objective of ILI run-to-run comparisons is to establish corrosion growth rates along the length of a given pipeline segment that are defensible, justifiable, and realistic without being overly conservative.

Establishing realistic corrosion growth rates based on ILI data can be challenging, especially when considering different technologies are sometimes employed between the subsequent ILI tool runs. One example of this is a circumferential magnetic flux leakage (MFL-C) ILI survey followed by an axial magnetic flux leakage (MFL) ILI survey. While the two technologies are similar in that both can detect and characterize metal loss anomalies, they differ in the direction of the applied magnetic field. As a result, the tools may detect and characterize (i.e., size) the anomalies differently depending on the shapes and orientations of the anomalies.

This paper explores the differences observed in the detection and sizing of different anomaly types by the two technologies, how these differences contribute to calculated corrosion growth rates, and what considerations should be made when comparing MFL and MFL-C ILI data for the purpose of determining corrosion growth rates.
Review of Hydrogen Induced Cracking of Mid-Wall Defects
Authors: Podnar McMahan Tara , Bubenik Thomas , Padgett B. Nikki , Al-Muslim Husain , Beavers John , Kulkarni Satish
Published: December 2022

There is the potential to demand more of existing infrastructure and introduce uncommon integrity threats as a result of societal challenges to building new cross-country pipelines, the need to traverse more challenging terrain, and the momentum for a hydrogen economy increases. One such threat is hydrogen induced cracking (HIC) of mid-wall defects. HIC is commonly defined in the literature as cracking that initiates within the mid-wall from reformation of molecular hydrogen at mid-wall defects, such as stringers, or microscopic voids in the line pipe steel. In 2020, the Pipeline Research Council International, Inc. (PRCI) funded a project, PRCI Project NDE-1-10, to review the pipeline industry’s current understanding of mid-wall HIC and to identify a potential management strategy for HIC as an integrity threat.

The project included a literature review of key factors influencing HIC and of the capabilities of non-destructive inspection technologies (both in-line and in the field) to detect, identify, and size mid-wall defects and any potential radial cracking associated with HIC. A summary of the key factors as well as non-destructive inspection technologies with the potential to detect and size the mid-wall defects with radial cracking was compiled. As a result of the literature review, gaps in knowledge and experience with HIC were identified. It was determined that there is opportunity to better understand hydrogen exposure, both the amount of hydrogen present in the environment and the amount of time in which the line pipe materials are exposed, required to initiate HIC. The literature review also identified improvement opportunities related to non-destructive inspection technologies with the ability to reliably and consistently detect and size HIC.

A management framework was developed, based upon the key factors that were identified, data offered through case studies by the steering committee, as well as industry subject matter expert interviews and feedback. The framework is comprised of traditional integrity management components with a focus on threat susceptibility, integrity assessment, severity determination, and assessment response. Using the segment’s threat history, environmental factors, and pipe material factors, a high-level threat susceptibility process was developed that categorizes pipeline or dynamic segments into high-high, high, moderate, low, and not covered priorities. A response for each categorization was also developed that ranges from performing an integrity assessment as soon as practical to opportunistic monitoring. This paper provides a high-level summary of the key factors for the threat of HIC, the gaps identified through the literature reviewed as well as industry outreach, and the integrity management framework developed as a result.
Fatigue Threat to Natural Gas Pipelines: An Analysis Approach
Authors: Davis Brett , Hudgins Alex , Bhargava Yash , Patrick Brian , Myca Konrad
Published: December 2022

The United States Pipeline and Hazardous Material Safety Administration (PHMSA) published the amended gas pipeline federal safety standards (49 CFR 192) in October 2019. The updated regulations provide provisions for the execution of fatigue crack growth analyses and remaining life estimates. The fatigue threat has been extended to applicable pipeline segments within the standard for both integrity management, as well as MAOP reconfirmation approaches. Fatigue behavior and analysis of pipelines has been well studied throughout the industry and has been the subject of many publications. However, the practical application of such analyses, which incorporates the use of structural mechanics, fracture mechanics, material property assessments, uncertainty quantification, and risk analysis, requires a procedural approach that connects inputs and outputs, is scalable, and allows for prioritization of pipeline segments. A key component of this process is leveraging a simple method, used on the front-end of the larger fatigue assessment, for identifying and evaluating assets at risk of fatigue crack growth and subsequent ultimate failure from the fatigue threat. The current work outlines a mechanics-based process by which operators can gauge and prioritize pipeline segments based on the susceptibility to fatigue crack growth.
Line Pipe HAZ Softening Susceptibility and Response
Authors: Dinovitzer Aaron , Guest Stuart , Slumkoski Zoe , Tiku Sanjay , Zamil Shafayet , Khotenko Nick , Begg Darren
Published: December 2022

Unexpected girth weld failures have occurred in newly constructed pipelines with acceptable line pipe materials and weldments (i.e., API 5L and 1104 compliant) and yet these welds fabricated without significant discontinuities failed in a ductile manner with strain localized in the weldment region. Heat affected zone (HAZ) softening was identified as one of the contributing factors in these failures. This paper presents the result of a research project developing a “simple” HAZ softening susceptibility test (i.e. easier to do right than wrong) that may be used identify materials prone to HAZ softening. The test developed in a research project supported by the Pipeline Research Council International (PRCI) is intended as a line pipe material susceptibility test rather than a weld procedure acceptance test which could consider the impact of the heating cycles of multi-pass weld procedures.

The test development included the optimization of the welding procedure, sample configuration and support to produce repeatable results, as well as the definition of a testing procedure susceptibility metric considering local maximum and average through thickness softening. The performance of the testing procedure was demonstrated by considering 20 steels, ranging from X52-X70, steel chemical compositions and 1963–2020 manufacturing dates, designed to represent a range of HAZ softening susceptibilities. The development work demonstrated that the potential for HAZ softening cannot be exclusively related to steel chemistry and that the magnitude of softening is correlated to the size (e.g., width) of the HAZ.

The single pass weld test developed and described in this work successfully demonstrated the relative susceptibility of line pipe steels. In addition, Cross weld tensile testing employing digital image correlation was used to illustrate the process of strain accumulation and localization promoted by HAZ softening and is presented in this paper to describe the failure process of affected materials and estimate their residual strength. The single pass weld test results presented may be used in a material acceptance test or identify materials that require attention in to weld application or alternate welding procedures. These results provide opportunities to learn and reduce the risks associated with HAZ softening and this developing sound weldments that can better resist axial load.
Assessing Geohazard Probability of Pipeline Failure: Lessons and Improvements From the Last 10 Years
Authors: Newton Sarah , Van Hove Joel , Porter Michael , Ferris Gerald
Published: December 2022

Geohazards, consisting of geotechnical hazards where ground movements impact pipelines and hydrotechnical hazards where pipelines cross watercourses, can threaten pipeline integrity, causing leaks or ruptures. Given the vast geographies traversed by pipeline infrastructure, geohazard frequency can be high requiring triage of large inventories of identified geohazard sites. Since 2012, field screening probability of failure algorithms have been used to assess and prioritize geohazard threats to pipeline integrity. These algorithms were developed using empirical data from failure case histories, engineering judgement from geohazard professionals, and statistical rates of pipeline impact, exposure, and failure. When combined with consequences, the algorithms provide semi-quantitative risk assessments. The risk assessments are used to compare geohazard threats to other pipeline integrity threats to support cost-benefit decisions for pipeline operation. The algorithms have been applied to 243,000 sites on 440,000 km of oil and gas gathering, transmission, and distribution pipelines primarily in Canada and the United States.

In this paper, lessons learned from applying probability of failure algorithms to geohazard sites over the past 10 years are shared. The algorithms have proved successful in that their use has allowed pipeline operators to focus their integrity management effort on higher probability of failure sites. Use of the algorithms also allows operators to reduce investment on low probability of failure geohazard crossings. For example, the probability of failure assessments provide justification for less frequent reinspection intervals of low probability of failure sites, while providing clear means of advocating for the need to mitigate and monitor high probability of failure geohazard sites. Over the past decade, recalibration of the algorithms has reduced conservatism in earlier versions. As well, advancements in data collection, storage, and quality assurance have been undertaken to improve accuracy.

This paper describes the methods used to assess probability of failure for pipeline landslide and watercourse crossings. The use cases and limitations of the algorithms are also discussed.
Engineering Critical Assessment of Dents and Dents With Cracks Using Inline Inspection Data
Authors: Krishna Shree
Published: December 2022

Dented pipes with typical strain measurements greater than 6% are considered unacceptable, and further assessment using the finite element (FE) procedure is conducted. FE procedures are conducted using specific dent profiles based on the shape of indenters. The actual shape of a real dent differs from the simplified dent shapes that are assumed in engineering critical assessment, thereby compromising the accuracy, especially if there are two side-by-side dents. Several papers used simplified indenter profiles to generate strain and critical damage values. Such a simplified profile can generate non-conservative results, especially if there is an interaction with a nearby dent or residual stresses from the weld. These drawbacks are resolved using an innovative workflow outlined in this paper.

This paper elaborates on developing an approach by creating the dent surface from the ILI measurement data to evaluate the dented pipes. The results illustrate the importance of using accurate ILI measurement data to obtain dent strains and dent-based damage. Residual stress from the presence of weld adjacent to the dent can also be used conveniently by these approaches and is more amenable for the wider types of analyses. Approaches outlined in the paper will also illustrate how to analyze the dented pipes with cracks conveniently. The presence of cracks at the dent would significantly increase the stress intensity factor. Crack assessment for dents with cracks is a tedious FE procedure, which can be simplified using the polynomial stress distribution. Stresses from a dented profile with the cracks are obtained using this analysis which can thereby be used for crack assessment. Stress intensity factors of the cracks in the dent can be obtained using these approaches and can be further used for crack assessment. Finally, the remaining life of dented pipes with and without cracks is presented using the FE analyses results.
Application of Strain Based Assessment in Support of Operational and Mitigation Decisions
Authors: Liu Banglin , Wang Yong-Yi , Chen Xiaotong
Published: December 2022

A confirmed pipeline displacement due to ground movements often requires operational decisions regarding flow restriction and/or field mitigation. Some of the more frequently employed techniques for assessing the magnitude of the applied strain (strain demand), such as in-line inertial measurement unit (ILI IMU) or pipe-soil interaction analysis, may not be able to accommodate the timeframe for such decisions. The resulting lack of quantified strain demand and strain demand limit can potentially cause prolonged service interruptions or unnecessary field work under unfavorable access conditions.

A multi-leveled strain-based assessment (SBA) process is presented that was designed to support operational and mitigative decisions after confirmed pipe displacements. At the lower level, the methodology utilizes pipe locator data in conjunction with generalized pipe displacement profiles for quick determination of strain demands. At the higher level, conventional pipe-soil interaction analysis is used to refine the strain demand estimate as additional site data become available. The tensile strain capacity (TSC) is determined using one of three available options based on data availability. Integrity assessments can then be performed for both the current operating condition and future scenarios. For sites deemed safe at the moment of assessment, allowable movements at a future point can be established based on the margins between the strain demand and strain capacity. The allowable movements can be used in conjunction with geotechnical assessment to establish re-assessment intervals and trigger further field verification or mitigation activities.

An example SBA of a landslide in the Appalachian region is presented to illustrate the applications of the multi-leveled process with key considerations and some practical constraints in mind. Two gas transmission pipelines in a shared right of way were displaced after a slope movement. Pipeline A was shut-in immediately due to a larger displacement while Pipeline B remained in operation pending an integrity assessment. An initial lower-level SBA indicated neither pipeline had a sufficient margin between the strain capacity and the strain demand. Pipeline B was shut-in as a result. The initial assessment also pointed to different directions for refined assessments. Pipeline A, with the higher TSC and demand estimates, was subject to a refined pipe-soil interaction analysis to reduce the potential over-estimation of the strain demand. Pipeline B, with the lower TSC and demand estimates, was subject to in-ditch NDE in a controlled excavation, so that the TSC estimate can be updated with accurate weld-specific flaw information. The refined assessment indicated sufficient margins of safety for both pipelines. Consequently, both lines were returned to service, and a slide repair was implemented.
Understanding Principal Drivers to Burst Pressure and Local Deformation of Pipes With SCC Colonies
Authors: Wang Yong-Yi , Wang Alex , Leis Brian , Rapp Steven C. , Vervake Gary
Published: December 2022

Two pups with SCC colonies were removed from service. The most dominant cracks in the colonies are short and deep. One of the pups had a bulge in the area of the SCC colony. The two pups were subjected to hydrostatic burst tests and detailed post-test metallurgical examination. A companion paper covers the formation, dormancy, and growth of these SCC colonies using forensic analysis. This paper covers two main elements aimed at understanding the behavior of pipes with SCC colonies and supporting the work covered in the companion paper:

(1) Burst pressure prediction, and

(2) Analysis of the bulge.

Burst pressure predictions were made with available material properties and flaw dimensions measured by MPI, UT, and PAUT prior to the actual burst tests. After the burst tests, the predictions were updated with more relevant material property data and the flaw dimensions obtained from fracture surfaces exposed. The modified Ln-Sec, CorLAS™, MAT-8, and Level 2 of API 579 burst pressure models and the associated Charpy to fracture toughness correlations were used. Two flaw interaction rules, CEPA and PRCI-CRES, were used to determine the single equivalent crack dimensions for input into the burst pressure models. The burst pressure predictions were compared with the experimentally measured burst pressures.

Of the multiple factors affecting the burst pressure prediction, the selection of flaw interaction rules has the most prominent impact on the accuracy of the burst pressure prediction. The selection of burst pressure models has a secondary impact with the exception of API 579, which tends to give lower burst pressure predictions than other models.

The formation of the bulge was simulated under different longitudinal/axial loading conditions and two levels of internal pressure. It is shown that the level of the residual bulge has a strong dependence on the severity of SCC (length, depth, and spatial distribution), the level of maximum internal pressure before depressurization, and the longitudinal stress state. Compressive longitudinal stress reduces the level of internal pressure needed to produce a bulge of the same magnitude when the severity of SCC remains constant. Multiple possible conditions could have existed to produce the observed bulge.
Enhancement of Mechanical Damage Crack Evaluation
Authors: Rana Arnav , Tiku Sanjay , Piazza Mark , Burns Tim
Published: December 2022

This paper presents the results of a project undertaken to enhance previously developed tools being adopted in an industry recommended practice (API RP 1183) for pipeline mechanical damage (MD) integrity assessment and management. This project builds on MD assessment and management tools, developed on behalf of Pipeline Research Council International (PRCI), Interstate Natural Gas Association of America (INGAA), Canadian Energy Pipeline Association (CEPA), American Petroleum Institute (API), other research organizations and individual pipeline operators and were included in API RP 1183. The specific tasks in the current project included the assessment and improvement of indentation crack formation strain estimation methods, evaluation of the impact of ILI measurement accuracy on dent integrity assessment, and level of conservatism (safety factor) inherent in different levels of dent fatigue life assessment incorporated in API 1183.
A Comprehensive Fitness for Service Engineering Assessment of Gas Pipeline Dents
Authors: Debnath Suborno , Roy Kshama , Wickie Robert , Kohandehghan Alireza
Published: December 2022

Mechanical damages such as dents are one of the most common threats to the structural integrity of buried pipelines traversing high population areas or mountainous terrains. Dents are defined as local inward depression in the pipe surface caused by external forces that produce pipe wall plastic deformation and a disturbance in the curvature of the pipe. Since not all dents affect the fitness for service (FFS) of a pipeline, dents identified by in-line inspection (ILI) tools need to be properly evaluated to determine the severity. This article provides a methodological framework to carry out a comprehensive fitness for service engineering assessment of dented natural gas pipelines using finite element analyses. The assessment is based on the evaluation of the dent formation strain, plastic collapse, local buckling, and pressure cycling fatigue failure modes. This FFS engineering assessment methodology addresses the susceptibility of dents to ductile fracture damages and stress-corrosion cracking integrity threats that can develop due to high membrane and bending loads in a dented pipe. This FFS assessment methodology has successfully been utilized to assess dents identified by ILI in gas pipeline systems. The results and the associated interpretation and discussions of the FFS assessment findings are presented herein.
Analytical and Experimental Assessment of Short Bolted Flange Nuts Subjected to Tensile Loads for Development of Mitigation Strategy
Authors: Brewer Jonathan , Sheets Colton
Published: December 2022

Analytical and experimental methods were used to develop a strategy for assessing short bolted threaded connections (studs and nuts) under tensile loading. Short bolting occurs when a threaded connection has some number of threads that remain unengaged. This unthreaded length is called shortfall. Analytical efforts primarily focused on predicting the failure loads and failure modes associated with various levels of shortfall. An analytical methodology for assessing short bolting is important as it allows an end user to develop a threat prioritization or integrity management program based on a desired level of risk tolerance. A risk averse, conservative approach could require that all nuts have sufficient engagement length to produce a tensile overload failure of the stud. A risk tolerant approach might utilize predicted failure load as an integrity criterion instead of predicted failure mode.

Development of the analytical models, including a review of existing literature, is described within this paper. The primary output of the analytical models includes the expected failure load as a function of the threaded connection engagement length and the critical “transition engagement length” at which the failure mode changes from thread shear to stud tension. Above this engagement length, the threaded connection is expected to fail due to tensile overload of the stud and is “full strength”. Below this engagement length, the threaded connection is expected to fail by thread shearing, at a load lower than the tensile strength of the stud.

To validate the analytical approaches, a series of full-scale tests were conducted using 1.5-inch and 2-inch diameter B7 studs (ASTM A193) and ASTM A194 2-H heavy hex nuts. Laboratory evaluation of the threaded connections consisted of dimensional measurements and tension-to-failure testing. Tension-to-failure testing consisted of applying increasing tension loads to the threaded connections with varying shortfall lengths. The failure mode of the test was recorded and compared to predictions from the analytical models. A total of 18 tension-to-failure tests were performed.

If nut and stud material and geometric properties are known, it was determined that analytical calculations based on SAE 770420 with a modified shear stress capacity defined as 0.5*UTS (ultimate tensile strength) results in the best match to the test results. The transition engagement length matched within 2% for both stud sizes. However, if the nut and stud material and geometric properties are unknown, analytical calculations based on ASME B1.1, Appendix B, with shear stress capacity defined as 0.5*UTS were found to be more appropriate. The transition engagement length matched within 2% for both stud sizes. Based on these analysis and testing results, a multilevel inspection program was defined to assess an asset system.
Phased Array Shot Scenario and Shot Sequence Optimization for Crack Detection Inline Inspection Tools
Authors: Haas Michael , Witte Henrik , Kopp Gerhard , Haberl Peter
Published: December 2022

Ultrasonic crack detection (UC) technology is a well-established methodology to address crack-like flaws in liquid product pipelines. The UC technology is based on shear bulk waves propagating in the pipe wall. For monolithic transducers, the angle of incidence (AOI) is defined by the mechanical inclination of the transducers with respect to the internal pipe wall surface. Changes in the AOI due to the differences in acoustic properties of the different liquid products therefore require changes in the mechanical layout. Ultrasonic inspection tools based on phased arrays offer a much higher level of flexibility regarding the ultrasound characteristics (e.g., AOI, beam width, focus) compared to tools based on monolithic transducers. In particular, multiple array elements can be grouped together in so-called virtual sensors and placed with element-pitch granularity on the array. This flexibility allows to develop a shot scenario optimized for the specific requirements presented in an inspection project, e.g., challenging long seam weld geometries. However, exploiting this configuration flexibility comes with a drawback: Each configuration requires an in-depth analysis of sound propagation paths between array and pipeline wall in order to avoid spurious sound propagation that can lead to undesired crosstalk. This analysis becomes even more relevant if multiple virtual sensors must be used simultaneously to guarantee high tool inspection speed. The authors present the methodology used in the phased array inline inspection tools to enable simultaneous usage of several virtual sensors on each array and to minimize the impact of spurious sound propagation on subsequent usages of virtual sensors. In particular, the authors demonstrate the application of a model of the inspection setup / shot scenario that allows computerized optimization of possible configuration options. We outline the configuration optimization procedure and present experimental validation results from pump tests confirming that data quality and inspection speed are well aligned with customer expectations.
X80 Heavy Gauge and Large Diameter Helical Line Pipe for Low Temperature Applications
Authors: Gaudet Michael J. , Rashid Muhammad , van der Breggen Ahmad , Dunnett Kendal , Arafin Muhammad
Published: December 2022

Demand for improved pipeline efficiency has directed designs towards larger diameters and higher operating pressures. High strength steel with increased wall thicknesses of the pipe provide for greater available pressure capacity for the pipeline. However, toughness of the line pipe, particularly at low temperature, is challenged when increasing the strength of the steel and with a greater wall thickness of the pipe.

This work discusses the efforts to optimize alloy and thermomechanical controlled processing (TMCP) designs to achieve X80 with good low temperature toughness. Two X80 helical line pipe steel designs are presented; X80-A with low Ni and X80-B with high Ni with gauges of 18.5 mm and 19.1 mm, respectively. This material was cast, rolled, and formed into pipe as part of production trials. Processing data is presented and shows good consistency was achieved in the trials. Results from the tensile and drop weight tear tests (DWTT) are discussed. Both X80-A and X80-B met tensile requirements for an X80 material with an average yield strength of 614 MPa and 586 MPa. In terms of DWTT, X80-A passed −5°C whereas X80-B passed both −20°C and −30°C. In terms of microstructures, nital and LePera etchings along with optical microscopy showed that X80-A and X80-B have fine grain ferrite microstructures with a minimal amount of martensite/retained austenite.

A larger data set consisting of X70 and X80 material from production and trials within the gauge range of 17.8 mm to 20.3 mm are introduced. The data set shows some expected general trends such as decreasing DWTT performance with increases to strength. Various TMCP factors such as roughing last pass temperature and mean flow stress as well as microstructure are also discussed with respect to their impact on DWTT results. Low Ni contents are shown on average to perform better than other levels in the current data set, owing mainly to the optimization efforts of developing a −5°C X80 product.
High Fidelity Distributed Fiber Optic Sensing for Landslide Detection
Authors: Murray Carrie , Jalilian Ehsan , Najeeb Arfeen , Toms Sam , Hossain Tasnim
Published: December 2022

Pipeline integrity management continues to adapt and improve with the adoption of new technologies. In 2016, Husky Midstream had a loss of containment incident on a 16-inch diameter pipeline on the south slope of the North Saskatchewan River in Saskatchewan, Canada. The incident was determined to be caused by ground movement resulting from a landslide complex. The landslide complex on the south slope contains two deep-seated compound basal shear slides as well as a near surface translational slide in low strength clay shales.

A robust state-of-the-art instrumentation monitoring program was implemented that included real-time geotechnical instrumentation, high fidelity distributed fiber optic sensing (HDS), repeat ILI and on-site weather data to identify, evaluate and monitor areas of ground and pipeline movement so that potential impacts to the pipelines could be mitigated. An early-warning system that included alarm thresholds was developed that identified when to proactively shut-in the pipeline.

The HDS monitoring comprised strain, acoustic and temperature sensing, and was installed to provide leak detection monitoring, however, it revealed an excellent correlation to the geotechnical, ILI and weather station monitoring data on the actively moving landslide complex. This paper shows a number of these correlations over the HDS monitoring period from October 2017 to November 2018. The HDS monitoring showed increased strain magnitudes following significant rainfall events that correlated to an acceleration in slope inclinometer (SIs fitted with shape accelerometer arrays, SAAs) and survey monument (SM) movement. Locations of high strain accumulation correlated to ILI locations of bending strain. Accumulated strain and displacements in SAAs and SMs were measured despite the lack of visual evidence of ground cracking on the right-of-way (ROW). Construction activity on the ROW was detected through acoustic and strain signatures.

As pipeline operators continue to include high fidelity fiber optic sensing as a continuous linear sensor along new and existing pipelines primarily as a leak detection tool, other critical applications, such as early detection of active landslides can be included as an important component of the integrity management system or separately as part of a robust monitoring system.
Reaching homogeneous field emission current from clusters of emitters with nonuniform heights
Authors: Filippov Sergey V. , Dall’Agnol Fernando F. , Popov Eugeni O. , Kolosko Anatoly G. , de Assis Thiago A.
Published: December 2022

In field electron emission from pointed structures in a cluster or in an array, electrostatic depolarization due to neighboring emitters diminishes the local field enhancement factor (FEF). This effect can limit the maximum macroscopic emission current from devices. If emitters in a cluster are regularly spaced and uniformly tall, the local FEF will always present significantly larger values at the edges, making most of the cluster ineffective. In this work, we explore conducting emitters in a cluster that are not uniformly tall and numerically calculate the local electrostatic field and the macroscopic emitted current over classical emitter’s surfaces using the Murphy–Good emission model. Our results show the conditions to homogenize and, therefore, optimize the emission current extractable from the cluster.
An efficient analysis of oblique reflection of airborne ultrasound beams from thin membranes for gas sensing
Authors: Ortega-Aguilar Alejandro , Velasco-Segura Roberto , Sandoval-Romero G. Eduardo , García-Valenzuela Augusto
Published: December 2022

The use of the angular spectrum method (ASM) to simulate the reflection of airborne ultrasound beams from a thin membrane separating air from a mixture of air and another gas is examined. The main advantage of this method is its high computing speed and efficiency for practical design calculations, suitable for sensing applications. The implemented ASM code is validated against custom Rayleigh integral code in a pure propagation simulation. In addition, ultrasound beam reflection calculations using ASM with finite element numerical results and experimental measurements are compared, finding good agreement in both cases. Then, ASM is used to estimate the sensitivity of specular reflection signals to variations in the composition of the incidence medium as a function of the angle of incidence. Conditions for which a reflection signal using inexpensive commercial ultrasound emitter/receiver at 40 kHz, in a simple configuration, offer a high enough sensitivity suitable for monitoring air quality indoors are found.
Lip hyper-articulation in loud voice: Effect on resonance-harmonic proximity
Authors: Garnier Maëva , Smith John , Wolfe Joe
Published: December 2022

Men and women speakers were recorded while producing sustained vowels at comfortable and loud levels. Following comfortable speech, loud levels were produced in three different conditions: first without specific instruction (UL); then maintaining the same pitch as the comfortable level (PL); and finally, keeping both pitch and lip articulation constant (PAL). The sound pressure level, the fundamental frequency (fo), the first two vocal tract resonances (R1 and R2), the lip geometry, and the larynx height were measured. For women, a closer proximity of R1 to its nearest harmonic, nfo, was observed in UL. However, no such increased proximity was found in PL, when speakers could, and did, hyper-articulate. Also, no increased proximity was observed in PAL, when lip articulation was constrained. No significant increase in R1:nfo proximity was observed in men in any of the three loud conditions. Finally, R2 was not observed significantly closer to a voice harmonic in loud speech, for neither men nor women.
Understanding the Teaching and Learning of Fundamental Movement Skills in the Primary Physical Education Setting: A Qualitative Study
Authors: Chan Cecilia H.S. , Ha Amy S.C. , Lander Natalie , Ng Johan Y.Y.
Published: December 2022

Purpose: Evidence demonstrates that many school children fail to master fundamental movement skills (FMS). Little is known about the teaching and learning of FMS in Hong Kong. This study aimed to capture voices from both teachers and students to better understand the current FMS practices in primary physical education Methods: Semistructured interviews with physical education teachers and focus groups with students were conducted. Thematic analysis of teacher transcriptions was performed. Student focus groups were analyzed using a framework approach, guided by TARGET (i.e., Task, Autonomy, Recognition, Grouping, Evaluation, and Time). Results: Several “teacher” level themes were developed: Self-efficacy (mis)judgment, limited pedagogical content knowledge, ineffective instructional and assessment strategies, insufficient teacher training, and deprioritization of skill development in physical education. Students perceived the need for a more student-centered approach to the teaching of FMS. Conclusions: Results highlighted the need for a different approach to initial and continuous teacher education in FMS. Further investigation into the most effective forms of teacher education is necessary, in order to improve the teaching and learning of FMS in schools.
Identification of Subunits for Novel Universal Vaccines against Three Predominant Serogroups and the Emerging O145 among Avian Pathogenic Escherichia coli by Pan-RV Pipeline
Authors: Wang Zhuohao , Xu Sixiang , Zheng Xiangkuan , Zheng Xiaofeng , Liu Meihan , Guo Genglin , Yu Yanfei , Han Xiangan , Liu Yuqing , Wang Kaicheng , Zhang Wei
Published: December 2022

With the emergence of drug resistance and the newly predominant serogroup O145, the control of Avian pathogenic
Escherichia coli
is facing a serious challenge; an efficient immunological method is urgently needed. Here, for the first time, we propose a high-throughput screening approach to search for universal protective antigens against the three traditional serogroups and the newly emerged O145.
Clone Dynamics and Its Application for the Diagnosis of Enzootic Bovine Leukosis
Authors: Hossain Md Belal , Kobayashi Tomoko , Makimoto Sakurako , Matsuo Misaki , Nishikaku Kohei , Tan Benjy Jek Yang , Rahman Akhinur , Rajib Samiul Alam , Sugata Kenji , Ohnuki Nagaki , Saito Masumichi , Inenaga Toshiaki , Imakawa Kazuhiko , Satou Yorifumi
Published: December 2022

Although BLV has been eradicated in some European countries, BLV is still endemic in other countries, including Japan and the United States. EBL causes huge economic damage to the cattle industry.
Nucleoside-Modified mRNA-Based Influenza Vaccines Circumvent Problems Associated with H3N2 Vaccine Strain Egg Adaptation
Authors: Gouma Sigrid , Furey Colleen , Santos Jefferson J. S. , Parkhouse Kaela , Weirick Madison , Muramatsu Hiromi , Pardi Norbert , Fan Steven H. Y. , Weissman Drew , Hensley Scott E.
Published: December 2022

This study shows that the nucleoside-modified mRNA-LNP vaccine platform is a promising alternative for egg-based influenza vaccines. We show that mRNA-LNP vaccines expressing H3 antigens elicit high levels of antibodies in mice and protect against H3N2 influenza virus infection.
Population Genomics Provide Insights into the Global Genetic Structure of
Colletotrichum graminicola
, the Causal Agent of Maize Anthracnose
Authors: Rogério Flávia , Baroncelli Riccardo , Cuevas-Fernández Francisco Borja , Becerra Sioly , Crouch JoAnne , Bettiol Wagner , Azcárate-Peril M. Andrea , Malapi-Wight Martha , Ortega Veronique , Betran Javier , Tenuta Albert , Dambolena José S. , Esker Paul D. , Revilla Pedro , Jackson-Ziems Tamra A. , Hiltbrunner Jürg , Munkvold Gary , Buhiniček Ivica , Vicente-Villardón José L. , Sukno Serenella A. , Thon Michael R.
Published: December 2022

Plant pathogens cause significant reductions in yield and crop quality and cause enormous economic losses worldwide. Reducing these losses provides an obvious strategy to increase food production without further degrading natural ecosystems; however, this requires knowledge of the biology and evolution of the pathogens in agroecosystems.
Genomic and Evolutionary Insights into Australian Toxigenic Vibrio cholerae O1 Strains
Authors: Bhandari Murari , Rathnayake Irani U. , Huygens Flavia , Nguyen Son , Heron Brett , Jennison Amy V.
Published: December 2022

Australia has its own indigenous
V. cholerae
strains, both toxigenic and nontoxigenic, that are associated with disease. Exotic strains are also detected in Australian patients returning from overseas travel.
Persistent and Severe Viral Replication in PBMCs with Moderate Immunosuppression Served an Alternative Novel Pathogenic Mechanism for Canine Morbillivirus
Authors: Feng Chuchu , Bu Yan , Cai Jiaxi , Zhao Guanyu , Li Zishu , Cheng Yuening , Zhang Xiaohao , Shi Yijun , Gao Yang , Li Xiangnan , Zheng Xuexing , Xue Xianghong
Published: December 2022

Despite widespread vaccine campaigns for domestic dogs, CDV remained an important infectious disease in vaccinated carnivores and wild species. In recent years, the regionally ongoing epidemic CDV isolates have emphasized conservation threats to, and potentially disastrous epidemics in, endangered species worldwide.
mRNA Expression of GATA3, FOXP3, TBX21, STAT3, NFKB1, and MAPK8 Transcription Factors in Humans and Their Cooperative Interactions Long-Term after Exposure to Chronic Radiation
Authors: Nikiforov V. S. , Akleyev A. V.
Published: December 2022

The results of mRNA expression of the GATA3, FOXP3, TBX21, STAT3, NFKB1, and MAPK8 transcription factors in peripheral blood cells of 264 residents of the Techa riverside villages of the Chelyabinsk and Kurgan regions, who were affected by chronic low dose-rate exposure in the 1950s, are shown. The range of individual doses to the red bone marrow due to external gamma exposure and 90Sr was 77.8–3507.1 mGy, and the mean dose was 706.3±46.3 mGy. It has been found that changes in the transcriptional response of the cell occur at the molecular level in the long term after chronic exposure. A modified expression of the immunoregulatory genes NFKB1 and MAPK8 in the peripheral blood cells of exposed people was found. A comparative analysis of the interaction of the studied mRNAs demonstrated the presence of a link between the MAPK8 and NFKB1 genes in the group of chronically exposed individuals. The results obtained may indicate the involvement of these transcription factors in the impairment of the immune response in the exposed population.
Painful left bundle branch block syndrome successfully treated by His-bundle pacing
Authors: Al-Shammari Ali , Edwards Tim , Al-Sharbatee Ghadah
Published: December 2022

Painful left bundle branch block (LBBB) syndrome is a rare cause of episodic chest pain associated with transient LBBB in the absence of flow-limiting coronary artery disease and myocardial ischaemia on functional testing. The aetiology of this phenomenon is not clear, but in many reported cases, these transient episodes of LBBB are rate related. The mechanism of chest pain is not well understood. Still, it is postulated that sudden loss of the ventricular contraction synchrony, which happens in LBBB, will induce a different perception of heartbeat in the brain with possible translation to the chest pain. Various treatment modalities were attempted in the past, including exercise training, medical therapy with beta-blockers and calcium channel blockers or device therapy with right ventricle pacing, biventricular pacing and lately, His-bundle pacing. This case report presents a woman with intermittent episodes of typical angina with periodic LBBB changes on her ECG. Telemetry monitoring and treadmill exercise tests show a 100% association between angina episodes and LBBB changes on ECG. Her transthoracic echocardiogram shows normal left ventricle structure and function, and her coronary angiogram shows no flow-limiting coronary artery disease. She has been successfully treated by His-bundle pacing, and her symptoms entirely resolved on her serial follow-up.
Associations of vision impairment and eye diseases with frailty in community-dwelling older adults: a nationwide longitudinal study in China
Authors: Shang Xianwen , Wu Guanrong , Wang Wei , Zhu Zhuoting , Zhang Xueli , Huang Yu , Hu Yijun , He Mingguang , Yu Honghua
Published: December 2022

Aims

To test whether vision impairment and major ophthalmic conditions are predictive of frailty.

Methods

The analysis included 5321 participants aged 60–95 years at baseline from the China Health and Retirement Longitudinal Study. Participants were enrolled in 2011 and followed up in 2013, and 2015 through a face-to-face interview. Distance/near vision impairment was defined by reporting poor eyesight and reporting excellent, very good, good or fair eyesight was used as the reference. A history of cataract surgery and glaucoma were also self-reported. Frailty was defined as the presence of ≥3 of the five components of the Fried phenotype: weakness, slowness, exhaustion, inactivity and shrinking.

Results

In the cross-sectional analysis, both near (odds ratio [OR] (95% confidence interval [CI]): 1.62 (1.30 to 2.00)) and distance (1.59 (1.30 to 1.96)) vision impairment was associated with a higher prevalence of frailty independent of confounders. In the longitudinal analysis, the multivariable-adjusted OR (95% CI) for incident frailty associated with glaucoma, distance vision impairment, near vision impairment and vision problem was 3.41 (1.46 to 7.99), 1.59 (1.17 to 2.17), 1.62 (1.17 to 2.23) and 2.11 (1.41 to 3.15), respectively. Vision problem was associated with decreased handgrip strength (β (95% CI): −1.47 (−2.20 to –0.75) kg) during follow-up. Individuals with glaucoma (−0.11 (−0.16 to –0.05) m/s), distance vision impairment (−0.02 (−0.03 to 0.00) m/s) or vision problem (−0.02 (−0.05 to 0.00) m/s) had decreased gait speed compared with the control group.

Conclusions

Vision problem, vision impairment and glaucoma are important predictors of frailty in older adults.
Impact of COVID-19 on access to cancer care in Rwanda: a retrospective time-series study using electronic medical records data
Authors: Habinshuti Placide , Nshimyiryo Alphonse , Fejfar Donald Luke , Niyigena Anne , Cubaka Vincent K , Karema Nadine , Bigirimana Jean Bosco , Shyirambere Cyprien , Barnhart Dale A , Kateera Fredrick , Fulcher Isabel
Published: December 2022

Introduction

The COVID-19 pandemic has caused disruptions in access to routine healthcare services worldwide, with a particularly high impact on chronic care patients and low and middle-income countries. In this study, we used routinely collected electronic medical records data to assess the impact of the COVID-19 pandemic on access to cancer care at the Butaro Cancer Center of Excellence (BCCOE) in rural Rwanda.

Methods

We conducted a retrospective time-series study among all Rwandan patients who received cancer care at the BCCOE between 1 January 2016 and 31 July 2021. The primary outcomes of interest included a comparison of the number of patients who were predicted based on time-series models of pre-COVID-19 trends versus the actual number of patients who presented during the COVID-19 period (between March 2020 and July 2021) across four key indicators: the number of new patients, number of scheduled appointments, number of clinical visits attended and the proportion of scheduled appointments completed on time.

Results

In total, 8970 patients (7140 patients enrolled before COVID-19 and 1830 patients enrolled during COVID-19) were included in this study. During the COVID-19 period, enrolment of new patients dropped by 21.7% (95% prediction interval (PI): −31.3%, −11.7%) compared with the pre-COVID-19 period. Similarly, the number of clinical visits was 25.0% (95% PI: −31.1%, −19.1%) lower than expected and the proportion of scheduled visits completed on time was 27.9% (95% PI: −39.8%, −14.1%) lower than expected. However, the number of scheduled visits did not deviate significantly from expected.

Conclusion

Although scheduling procedures for visits continued as expected, our findings reveal that the COVID-19 pandemic interrupted patients’ ability to access cancer care and attend scheduled appointments at the BCCOE. This interruption in care suggests delayed diagnosis and loss to follow-up, potentially resulting in a higher rate of negative health outcomes among cancer patients in Rwanda.