bluuebunny/crossref_metadata_2025 huggingface dataset:
Differences in plumage coloration between ventral and dorsal regions on Atlantic Forest birds
Authors: De La Torre Gabriel Massaccesi , Aguiar de Souza Penha Victor , Manica Lilian Tonelli
Published: December 2024

Plumage coloration is an important trait for communication signalling and camouflage, enabling birds to provide cues of health condition and avoid predators. Such coloration can differ among body regions, with some regions presenting conspicuous coloration, while others are more discreet. Plumage coloration can also be associated with species' life‐history traits, such as diet, habitat and nest type. Despite the relevance to ecology and evolution of bird plumage coloration, little is known regarding the relationship between the coloration of ventral and dorsal regions of bird species, especially in the Atlantic Forest, a global hotspot of biodiversity. Here we assessed plumage brightness and saturation of the dorsal and ventral regions of Atlantic Forest birds, and analysed the differences in coloration and colour variability between the regions. We also tested whether sex dichromatism, nest type, diet, habitat and foraging stratum preference are related to plumage coloration. We found that dorsal regions tend to be darker, more achromatic and less variable across species when compared to ventral regions. Additionally, plumage coloration of bird species incubating in open nests is brighter than in birds from closed nests, while species with sexual dichromatism tend to present darker ventral regions. Our results bring new insights into the role of plumage coloration in Atlantic Forest bird ecology, suggesting that different evolutionary forces may act in different body regions.
Effect of additive content on the microstructure and room‐temperature and high‐temperature mechanical properties of Si3N4 ceramics
Authors: Du Songmo , Li Fei , Zhang Jie , Chen Zhanglin , Zhang Shijia , Zhao Shuo , Zhao Dengke , Fan Binbin , Chen Kexin , Liu Guanghua
Published: December 2024

Si3N4 ceramics with uniform grain size distribution were fabricated using spark plasma sintering method and post‐heat treatment. The effect of sintering additive content on the grain growth and room‐temperature and high‐temperature mechanical properties of Si3N4 ceramics were studied. By modulating the competitive growth of β‐Si3N4 grains along the basal and the prism planes, the grains in Si3N4 ceramics were homogeneous. The room‐temperature and high‐temperature flexural strength of the samples after post‐heat treatment were tested. At temperature above 1300°C, the samples with lower sintering additive content exhibit higher strength.
AQUABEAM robotic system use‐results survey: Aquablation for the treatment of lower urinary tract symptoms due to benign prostatic hyperplasia in the Japanese Population
Authors: Hinata Nobuyuki , Fujisawa Masato , Yamaguchi Raizo , Katsura Daiki , Kitano Hiroyuki , Sekino Yohei , Yoshioka Kunihiko , Koike Shin , Odagaki Yu , Ozawa Yu , Aoki Keisuke , Miyauchi Toshihide , Watanabe Susumu , Barber Neil , Elterman Dean , Afshar Ali , Saito Keisuke , Ide Hisamitsu , Horie Shigeo
Published: December 2024

Objectives

To evaluate the safety, efficacy, and patient‐reported outcomes of Aquablation therapy using the AQUABEAM Robotic System for the treatment of lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH) in a Japanese population.

Methods

This post‐market use‐results survey included 103 Japanese men with BPH who underwent Aquablation across five centers with previously Aquablation naïve physicians. Data were collected at baseline, during the procedure, at discharge, and at 3 and 6 months post‐procedure. Key outcomes included International Prostate Symptom Score (IPSS), quality of life (QoL), uroflowmetry parameters, and adverse events.

Results

The mean age of patients was 71.1 years, and the average prostate size was 82.3 mL. At 6 months, the mean IPSS significantly improved from 18.1 ± 9.0 to 6.1 ± 5.0 (p < 0.0001), and QoL scores improved from 4.9 ± 1.3 to 1.8 ± 1.3 (p < 0.0001). Uroflowmetry showed a significant increase in Qmax from 8.3 ± 4.4 to 15.5 ± 7.8 mL/s (p < 0.0001) and a decrease in post‐void residual volume (PVR) from 85.6 ± 107.2 to 43.3 ± 60.0 mL (p = 0.0006). At the 30‐day primary safety endpoint, there were no reported adverse events of pad‐use incontinence, erectile dysfunction, or ejaculatory dysfunction reported, and no device‐related serious adverse events were reported. One subject (0.97%) experienced a Clavien–Dindo grade 3 adverse event.

Conclusions

Aquablation therapy using the AQUABEAM Robotic System is a reproducible, safe, and effective treatment for Japanese men with BPH, providing significant improvements in LUTS and QoL with a favorable safety profile.
Characteristics of paracetamol poisoning in a local health network and consistency of hospital management with national guidelines
Authors: Hurley Simon P. , Horwood Chris , Mallon Jake , Mangoni Arduino A. , Inglis Joshua M.
Published: December 2024

The management of paracetamol poisoning in our local health network and consistency with national guidelines is unclear. We conducted a 4‐month retrospective study of all paracetamol poisonings identified in two South Australian hospitals. Most presentations were deliberate self‐poisoning (90.7%) with immediate‐release formulations (88.0%). Although most were managed in accordance with national guidelines, there were deficiencies in documentation of the poisoning details and patient weight as well as cases of underdosing of the antidote. Quality improvement initiatives are needed.
Childhood adversity is associated with reduced threat‐safety discrimination and increased fear generalization in 12‐ to 16‐year‐olds
Authors: Samaey Celine , Lecei Aleksandra , Jackers Maarten , Jennen Lise , Schruers Koen , Vervliet Bram , Boets Bart , van Winkel Ruud
Published: December 2024

Background

Childhood adversity poses a major transdiagnostic risk for a host of psychiatric disorders. Altered threat‐related information processing has been put forward as a potential process underlying the association between childhood adversity and psychiatric disorders, with previous research providing support for decreased discrimination between threat and safety cues, in both children and adults exposed to adversity. This altered threat‐safety discrimination has been hypothesized to stem from increased generalization of fear, yet to date, this hypothesis has not been tested in youth.

Methods

Here, we investigate whether childhood adversity is associated with fear generalization during adolescence. 119 adolescents between 12 and 16 years of age (mean = 13.95), of whom 63 exposed to childhood adversity, completed a fear generalization paradigm. Fear conditioning was assessed through trial‐by‐trial US expectancy ratings and post‐experimental ratings of fear, valence and arousal. Additionally, we administered a perceptual discrimination task to assess the potential impact of perceptual discrimination abilities upon fear generalization.

Results

In line with our hypotheses, results showed that childhood adversity is associated with (1) reduced threat‐safety differentiation during fear acquisition and (2) increased fear generalization in both boys and girls, albeit to a different extent, as boys showed more generalization towards safety cues while girls showed more generalization towards dangerous cues. Moreover, this overgeneralization of fear could not be attributed to group differences in perceptual discrimination.

Conclusions

Altered fear learning may be an important process through which adversity increases risk for the development of psychopathology. Longitudinal research is essential to elucidate risk and resilience patterns following childhood adversity.
Validation of an Oral Health Tool for Clinicians to Screen Patients With Cardiovascular Disease
Authors: Sanchez Paula , Kezhekkekara Shwetha , Ajwani Shilpi , Wei Anlai , Wong Jaren , Wu Howard , Uddin Sanjida , Sukarieh Yasin , O'brien Jessica , George Ajesh
Published: December 2024

Aims

To develop and validate a screening tool to identify patients with cardiovascular disease at risk of poor oral health and requiring referrals.

Design

This study was part of a larger pilot study involving a cross‐sectional survey and an oral health assessment conducted with patients with cardiovascular disease.

Methods

A four‐item screening tool was developed by an expert panel and validated through a cross‐sectional survey of patients with cardiovascular disease. The survey contained the tool and the oral health impact profile (OHIP‐14) (first gold standard). Additionally, all survey participants were provided a clinical oral health assessment (second gold standard). Sensitivity and specificity analysis was undertaken comparing the tool to the two gold standards to assess patients with cardiovascular disease at risk of poor oral health.

Results

Three hundred and twenty‐one participants completed the cross‐sectional survey and eighty nine undertook the oral health assessment. Results from both approaches showed that the tool had high sensitivities (OHIP‐14 = 89%, Oral assessment = 88%) and low specificities (OHIP‐14 = 33% and Oral assessment = 24%).

Conclusion

The four‐item screening tool is a simple and valid tool to identify patients with cardiovascular disease at risk of poor oral health and requiring a dental referral. The tool could be incorporated into routine practice of nurses across various cardiac settings.
Caregiver Feeding Behaviours and Child Dietary Diversity and Growth in Rural Bangladesh
Authors: Chowdhury Zaynah T. , Hurley Kristen M. , Shaikh Saijuddin , Mehra Sucheta , Ali Hasmot , Shamim Abu Ahmed , Christian Parul
Published: December 2024

This study examined relations between caregiver feeding behaviours, child dietary diversity and anthropometry at 24 months of age in rural Bangladesh. Twenty‐four hours dietary recall, weight and length data were collected on 4733 children. Factor analysis was applied to an 11‐item caregiver feeding behaviours scale administered at 24 months, revealing two constructs: responsive/involved (five items) and forceful (six items); each dichotomised to reflect low and high use. Stunting (length‐for‐age Z‐score < −2), wasting (weight‐for‐length Z‐score < −2) and underweight (weight‐for‐age Z‐score < −2) were defined using international growth reference standards. Associations between feeding behaviours, dietary diversity score (DDS, food groups consumed; range 0–7) and anthropometric indicators were examined using multivariable linear or logistic regression models, adjusting for study design, confounders and intervention arm. Mean (SD) age of children in the study was 24.1 (0.3) months. Mean (SD) DDS was 3.7 (1.4), with 55% of children meeting minimum dietary diversity (MDD, DDS ≥ 4). Stunting, wasting and underweight were 40%, 19% and 42%, respectively. Use of high responsive/involved feeding behaviours (reported in 71% of mothers) was associated with higher DDS (0.09, 95% confidence interval [CI]: 0.001, 0.17) and higher odds of achieving MDD (OR: 1.17; 95% CI: 1.02, 1.33) but not with anthropometric outcomes. Use of high forceful feeding behaviours (reported in 34% of mothers) was associated with lower DDS (−0.12, 95% CI: −0.21 to 0.04), lower odds of achieving MDD (OR: 0.82, 95% CI: 0.72, 0.93), and higher odds of underweight (OR: 1.38, 95% CI: 1.22, 1.56) and wasting (OR: 1.55, 95% CI: 1.33, 1.81). In Bangladesh, responsive/involved feeding was associated with higher child dietary diversity whereas forceful feeding was associated with lower dietary diversity and undernutrition. Future research is needed to understand causality and test the effect of responsive feeding interventions on the promotion of child growth.
Defaunation Increases Clustering and Fine‐Scale Spatial Genetic Structure in a Small‐Seeded Palm Despite Remaining Small‐Bodied Frugivores
Authors: Lamperty Therese , Diaz‐Martin Zoe , Swamy Varun , Karubian Jordan , Choo Juanita , Dunham Amy E.
Published: December 2024

Anthropogenic pressures such as hunting are increasingly driving the localised functional extinctions of large‐ and medium‐sized wildlife in tropical forests, a phenomenon broadly termed ‘defaunation’. Concurrently in these areas, smaller‐bodied species benefit from factors such as competitive release and increase in numbers. This transformation of the wildlife community can impact species interactions and ecosystem services such as seed dispersal and seed‐mediated geneflow with far‐reaching consequences. Evidence for negative genetic effects following defaunation is well‐documented in large‐seeded plants that require large frugivores for long‐distance seed dispersal. However, how defaunation affects plants with small or medium‐small seeds (< 1.5 cm), which tend to be consumed and dispersed by frugivorous mutualists of a range of body sizes and responses to anthropogenic threats, is not well understood. To better understand defaunation's impacts on tropical plant communities, we investigated spatial and genetic patterns in a hyperabundant medium‐to‐small‐seeded palm, Euterpe precatoria in three sites with different defaunation levels. Results indicate that defaunation is associated with higher fine‐scale spatial genetic structure among seedlings and increased spatial clustering within seedling cohorts and between seedlings and conspecific adults, as well as a reduction in nearest‐neighbour distances between seedlings and conspecific adults. There were no clear effects on inbreeding or genetic diversity. However, we caution these trends may indicate that defaunation reduces seed dispersal services for species previously presumed to be robust to deleterious effects of losing large frugivores by virtue of having smaller seeds and broad suites of dispersal agents, and negative downstream effects on genetic diversity could occur.
Automated identification of Chagas disease vectors using AlexNet pre‐trained convolutional neural networks
Authors: Miranda Vinícius L. , Oliveira‐Correia João P. S. , Galvão Cleber , Obara Marcos T. , Peterson A. Townsend , Gurgel‐Gonçalves Rodrigo
Published: December 2024

The 158 bug species that make up the subfamily Triatominae are the potential vectors of Trypanosoma cruzi, the etiological agent of Chagas disease. Despite recent progress in developing a picture‐based automated system for identification of triatomines, an extensive and diverse image database is required for a broadly useful automated application for identifying these vectors. We evaluated performance of a deep‐learning network (AlexNet) for identifying triatomine species from a database of dorsal images of adult insects. We used a sample of photos of 6397 triatomines belonging to seven genera and 65 species from 27 countries. AlexNet had an accuracy of ~0.93 (95% confidence interval [CI], 0.91–0.94) for identifying triatomine species from pictures of varying resolutions. Highest specific accuracy was observed for 21 species in the genera Rhodnius and Panstrongylus. AlexNet performance improved to ~0.95 (95% CI, 0.93–0.96) when only the species with highest vectorial capacity were considered. These results show that AlexNet, when trained with a large, diverse, and well‐structured picture set, exhibits excellent performance for identifying triatomine species. This study contributed to the development of an automated Chagas disease vector identification system.
Increased chloroplast occupancy in bundle sheath cells of rice hap3H mutants revealed by Chloro‐Count: a new deep learning–based tool
Authors: Lambret Frotte Julia , Buarque de Gusmão Pedro P. , Smith Georgia , Lo Shuen‐Fang , Yu Su‐May , Hendron Ross W. , Kelly Steven , Langdale Jane A.
Published: December 2024

There is an increasing demand to boost photosynthesis in rice to increase yield potential. Chloroplasts are the site of photosynthesis, and increasing their number and size is a potential route to elevate photosynthetic activity. Notably, bundle sheath cells do not make a significant contribution to overall carbon fixation in rice, and thus, various attempts are being made to increase chloroplast content specifically in this cell type.

In this study, we developed and applied a deep learning tool, Chloro‐Count, and used it to quantify chloroplast dimensions in bundle sheath cells of OsHAP3H gain‐ and loss‐of‐function mutants in rice.

Loss of OsHAP3H increased chloroplast occupancy in bundle sheath cells by 50%. When grown in the field, mutants exhibited increased numbers of tillers and panicles. The implementation of Chloro‐Count enabled precise quantification of chloroplasts in loss‐ and gain‐of‐function OsHAP3H mutants and facilitated a comparison between 2D and 3D quantification methods.

Collectively, our observations revealed that a mechanism operates in bundle sheath cells to restrict chloroplast occupancy as cell dimensions increase. That mechanism is unperturbed in Oshap3H mutants but loss of OsHAP3H function leads to an increase in chloroplast numbers. The use of Chloro‐Count also revealed that 2D quantification is compromised by the positioning of chloroplasts within the cell.
Proper activity of the age‐dependent miR156 is required for leaf heteroblasty and extrafloral nectary development in Passiflora spp.
Authors: Soares Jessica Ribeiro , Robledo Kerly Jessenia Moncaleano , de Souza Vinicius Carius , Dias Lana Laene Lima , Silva Lazara Aline Simões , da Silveira Emerson Campos , Souza Claudinei da Silva , Sousa Elisandra Silva , Sodrzeieski Pedro Alexandre , Sarmiento Yoan Camilo Guzman , de Matos Elyabe Monteiro , Falcão Thais Castilho de Arruda , Fialho Lilian da Silva , Guimaraes Valeria Monteze , Viccini Lyderson Facio , Pierdona Flaviani Gabriela , Romanel Elisson , Fouracre Jim , Otoni Wagner Campos , Nogueira Fabio Tebaldi Silveira
Published: December 2024

Passion flower extrafloral nectaries (EFNs) protrude from leaves and facilitate mutualistic interactions with insects; however, how age cues control EFN growth remains poorly understood.

Here, we examined leaf and EFN morphology and development of two Passiflora species with distinct leaf shapes, and compared the phenotype of these to transgenics with manipulated activity of the age‐dependent miR156, which targets several SQUAMOSA PROMOTER‐BINDING PROTEIN‐LIKE (SPL) transcription factors.

Low levels of miR156 correlated with leaf maturation and EFN formation in Passiflora edulis and P. cincinnata. Accordingly, manipulating miR156 activity affected leaf heteroblasty and EFN development. miR156‐overexpressing leaves exhibited less abundant and tiny EFNs in both Passiflora species. EFN abundance remained mostly unchanged when miR156 activity was reduced, but it led to larger EFNs in P. cincinnata. Transcriptome analysis of young leaf primordia revealed that miR156‐targeted SPLs may be required to properly express leaf and EFN‐associated genes. Importantly, altered miR156 activity impacted sugar profiles of the nectar and modified ecological relationships between EFNs and ants.

Our work provides evidence that the miR156/SPL module indirectly regulates EFN development in an age‐dependent manner and that the EFN development program is closely associated with the heteroblastic developmental program of the EFN‐bearing leaves.
Detection of Amyloid‐β Peptides in Gingival Crevicular Fluid and Its Effect on Oral Pathogens
Authors: Liao Yue , Chen Hui‐Wen , Qiu Che , Shen Hui , He Zhi‐Yan , Song Zhong‐Chen , Zhou Wei
Published: December 2024

Periodontitis is the most common oral inflammatory disease, contributing to the onset and progression of Alzheimer's disease. However, a full investigation has not been performed on the expression level of amyloid‐β (Aβ) peptides in gingival crevicular fluid (GCF) and its effects on oral pathogens. This study aimed to analyze the expression level of Aβ peptides in GCF of patients with periodontitis and the effects of Aβ peptides against common oral pathogens. GCF samples were collected from patients with periodontitis (n = 15) and periodontally healthy people (n = 10). The antimicrobial effects of Aβ peptides were evaluated on four common oral pathogenic strains using an MTT assay, crystal violet staining, fluorescence microscope, and transmission electron microscope. The protein levels of Aβ40 and Aβ42 were upregulated in the GCF of periodontitis group compared with the healthy group. Both Aβ40 and Aβ42 exhibited antimicrobial effects on Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, and Lactobacillus acidophilus in both planktonic and biofilm conditions. Further, only Aβ40 showed an antimicrobial effect on the Fusobacterium nucleatum. The results of this study demonstrate that Aβ peptides in GCF may be a relevant indicator of periodontitis status. Besides, the antimicrobial peptides derived from Aβ peptides have great potential in periodontal therapy.
Desempaquetando la argumentación: tensiones identitarias y epistémicas en educación superior
Authors: Brañez-Medina Roberto Francisco
Published: December 2024

Este estudio desempaqueta tres prácticas letradas centrales en la escritura argumentativa en educación superior: planteamiento de una postura, búsqueda bibliográfica confiable y elaboración de esquemas argumentativos. Teóricamente, inscrita en las literacidades académicas y estudios recientes en Latinoamérica con un enfoque sociocultural, crítico y de justicia social, se entiende a la escritura como una práctica social. Metodológicamente, esta investigación con enfoque etnográfico parte del seguimiento comparativo de la trayectoria de ocho estudiantes en un curso universitario de escritura argumentativa, a partir de conversaciones cíclicas sobre sus avances, un análisis crítico de estos y revisión de documentos institucionales. Los resultados concluyen que los estudiantes procuran producir una escritura alineada con una visión objetivizante del conocimiento reproducido/promovido en educación superior. Esta propuesta institucional relega sus voces personales a un segundo plano y alienta identidades “administrativas-académicas” centradas en la recolección y gestión de “fuentes confiables” y la elaboración de esquemas argumentativos que operativizan la producción epistémica en estos espacios letrados. Así, la investigación contribuye al cuestionamiento de literacidades que se abstraen de la justicia social, consolidadas en educación superior como prácticas hegemónicas.
Multidimensional Modeling of Mixture Formation in a Hydrogen-Fueled Heavy-Duty Optical Engine With Direct Injection
Authors: Wang Yiqing , Scarcelli Riccardo , Bestel Diego , Demir Sinan , Srna Aleš
Published: December 2024

Hydrogen (H2), as a carbon-free fuel, is considered as one of the most promising solutions to reduce the carbon footprint of hard-to-decarbonize energy and transportation sectors. As such, hydrogen-fueled internal combustion engines (H2 ICEs) have recently been receiving increasing attention, particularly in applications such as on-road/off-road heavy-duty transport and combined heat and power. The direct injection (DI) of gaseous hydrogen into the combustion chamber offers great potential for achieving high power density and high engine efficiency, while mitigating the risk of backfire and reducing pre-ignition. However, the numerical simulation of H2 DI system remains a formidable challenge associated with the high computational cost of reproducing compressible supersonic flow and shocks in narrow injector passages and in near-nozzle regions. In general, there is a lack of well-established and validated practices for the modeling of high-pressure H2 DI in large-bore engines. To this end, this study focuses on computational fluid dynamics (CFD) modeling of the mixture formation process in a heavy-duty optical engine employing a medium-pressure H2 DI system. Both large eddy simulations (LES) and Reynolds Averaged Navier–Stokes (RANS) simulations are performed and evaluated against optical data. Gaseous hydrogen is injected into the combustion chamber via a centrally located outward opening hollow-cone injector at a pressure of 40 bar. Simulations are carried out for two injection timings, namely, −120 and −60 °CA. The numerical predictions for H2 distribution in different horizontal and vertical planes during the compression stroke are systematically compared against optical data obtained through planar laser-induced fluorescence (PLIF) measurements. Overall, the LES approach using the Dynamic Structure model is found to have good predictive capabilities for the early jet penetration in terms of length and shape, as well as the later H2 distributions. However, the unsteady RANS approach with the renormalization group k−ϵ model, which is widely used by industry to model heavy-duty ICEs, significantly underpredicts the H2 mixing, even at similar mesh resolution to that used in LES. These results indicate that there is a need for the improvement of mixing submodels within the RANS approach when applied to H2 DI simulations.
Sensitivity of Heat Transfer to the Cross Section Geometry of Cylinders
Authors: Sambu Mathan , Derakhshandeh Javad Farrokhi , Zaman Izzuddin
Published: December 2024

This study investigates the phenomenon of vortex shedding and the heat transfer performance of bluff bodies, including smooth and sharp-edged cylinders. The examined geometries include square, triangular, hexagonal, and bullet-shaped bodies. The results are compared with a smooth circular cylinder standardizing the hydraulic diameter (Dh) across all bluff bodies and maintaining a Reynolds number within the range of 100 ⩽ Re ⩽ 200. The thermofluidic results are carefully examined and compared to determine the optimal conditions for maximum heat transfer rates, as measured by the Nusselt number. It is found that the Strouhal number, and thus the vortex shedding frequency, of cylinders with smooth surfaces differs significantly from those with sharp edges. It is demonstrated that hexagonal cylinders have up to 33% higher St than other geometries. Due to the flow dynamics in the wake of the cylinders, the heat transfer rates are lowest in square geometry and highest in circular geometry. Based on the analysis, bluff bodies can be classified into two primary groups: (i) bluff bodies with up to four edges are classified as “nonsmooth bluff bodies,” and (ii) those with six or more edges behave similarly to “smooth surface cylinders.”
Fluid Flow and Heat Transfer of Nanofluids Inside Helical Tubes at Constant Wall Temperature
Authors: Nazari S. , Rezaei E. , A. Moshizi S.
Published: December 2024

This paper investigates the forced convection of alumina-water nanofluids within helical tubes, maintaining a constant wall temperature and assuming thermal equilibrium between the nanoparticles and the base fluid. The nanofluid model incorporates the effects of alumina (Al2O3) nanoparticle volume fraction, diameter, and temperature on thermophysical properties. The governing equations are solved using the Forward-Time Central-Space Finite Volume method in conjunction with the simple algorithm. Numerical results are validated against experimental data, demonstrating high accuracy. The study explores the effects of pitch size, curvature ratio, nanoparticle volume fraction, nanoparticle diameter, and Reynolds number on velocity contours, temperature profiles, secondary flow, thermophysical properties, friction coefficient, and heat transfer rate. Additionally, the figure of merit evaluates the impact of these parameters on the thermal performance of the system. The results indicate that an increase in Reynolds number and nanoparticle diameter negatively affects thermal performance, while higher nanoparticle volume fraction, curvature ratio, and pitch size enhance it. Furthermore, incorporating nanoparticles in straight tubes proves to be more advantageous compared to helical tubes. This study tested volumetric ratios of 1%, 2%, and 4%, which resulted in increases in heat transfer coefficients of 21%, 32%, and 43%, respectively, compared to pure water under similar conditions, such as Reynolds number and coil pitch.
A Single-Loop Method for Time-Variant Reliability Sensitivity Analysis of Motion Mechanisms Using Bayes’ Theorem
Authors: Zha Congyi , Pan Chenrong , Sun Zhili , Liu Qin
Published: December 2024

Time-variant reliability sensitivity (TRS) analysis can measure the effect of input factors on the structure/mechanism failure. The traditional method for TRS analysis employs a nested sampling procedure, with computational cost depending on the number of input factors. To address the above weaknesses, a single-loop method is developed for TRS analysis. Based on Bayes’ theorem, the sensitivity measure is derived and expressed by the difference between the probability density function (PDF) and the failure-conditional PDF. This derivation allows for TRS analysis to be performed with just one set of samples, where the computational complexity does not depend on the number of inputs. Then, the procedures for Monte Carlo simulation (MCS) are listed based on the innovative estimation of the sensitivity index. Three examples involving numerical and engineering problems are employed to validate the proposed strategy, with the direct MCS introduced for comparison. The results reveal that the proposed strategy provides satisfactory TRS analysis while significantly saving computational resources.
Dealing With Epistemic Uncertainties in Reliability-Based Pipeline Integrity Management
Authors: Lu Dongliang , Gong Peng , Tomic Aleksandar
Published: December 2024

A key advantage of reliability-based integrity management is that it provides a consistent framework for explicit consideration of various uncertainties in the modelling and decision-making process. Uncertainties involved in reliability-based analyses are often classified into two categories, aleatory uncertainties, and epistemic uncertainties. Aleatory uncertainties are uncertainties considered “intrinsic” to system and thus are often challenging to further reduce, whereas epistemic uncertainties are subjective uncertainties that arise due to incomplete analyst knowledge. As such, epistemic uncertainties are often referred to as lack of knowledge uncertainties and they can be further reduced as new information comes to light.

There are two major implications stemming from the differentiation between aleatory and epistemic uncertainties: (1) the estimated reliability performance and risk level calculated from reliability-based models are the results from a combination of both aleatory and epistemic uncertainties, and thus differing from the actual reliability performance of a system due to additional uncertainties from the lack of complete knowledge; (2) the modelling and decision-making process involves understanding and characterizing aleatory and epistemic uncertainties, including evaluating options for further reduction of epistemic uncertainties for more refined risk and reliability results.

This paper discusses two commonly used approaches for dealing with epistemic uncertainties in reliability-based integrity management. The first approach is to have an explicit separation of epistemic and aleatory uncertainties involved in the analysis and produce a set of reliability and risk results corresponding to different levels of epistemic uncertainties. The advantage of this approach is that it can provide a simplified overview of the sensitivity of the results to epistemic uncertainties, which eases the evaluation of various options related to further reducing the epistemic uncertainties. However, for certain cases, the separation of epistemic and aleatory uncertainties can be challenging due to the subjectivity that is involved and potential correlations between epistemic and aleatory uncertainties. The second approach is to perform the full reliability-based analyses initially without considering the types of uncertainties. The differentiation of aleatory and epistemic uncertainties is performed in follow-up sensitivity analyses that evaluate the cost and benefits associated with various options to reduce epistemic uncertainty. This approach provides a more comprehensive analysis and decision-making process for dealing with epistemic uncertainties, but it could require significantly more modelling and analysis effort. Examples are presented in the paper to illustrate the two approaches and their advantages and disadvantages are demonstrated and discussed.
Prediction of Ductile Fracture Arrest in Natural Gas Pipelines Using the Crack Tip Opening Angle
Authors: Bassindale Chris , Wang Xin , Tyson William R. , Xu Su
Published: December 2024

In this paper, an analytical equation is developed to predict fracture arrest CTOA requirements for gas pipelines pressurized with natural gas that undergo single phase decompression using finite element (FE) analysis. The FE model is briefly reviewed. Dynamic pipe fracture simulations were performed to determine fracture resistance curves (crack velocity as a function of pressure at constant CTOA) for modern materials and geometries. American petroleum Institute (API) standard X80 and X100 steels were examined. Pipe diameters of 914 mm, 1219 mm, and 1422 mm, and diameter to thickness ratios ranging from 50 to 100 were considered. The commercial finite element code ABAQUS 2017x-explicit was used to generate the models and solve the analyses. The constant CTOA model was implemented through a user subroutine in conjunction with shell elements. Backfill effects were modelled using smooth particle hydrodynamics and the flap pressure profile was modelled using experimental data from previous burst tests. A CTOA-modified Two-Curve approach was used to determine the arrest CTOA for a given material and geometry. An equation for specification of the arrest CTOA as a function of steel grade and design parameters (thickness, diameter, and material properties) is presented for a gas that undergoes single-phase decompression. The proposed equation was validated through comparison with experimental data.
Comparative Fracture and Fatigue Testing of Selected Pipeline Microstructures in Gaseous Hydrogen Environment
Authors: Hopkin Sarah , Bezensek Bostjan , Martin Tom , Guijt Wim
Published: December 2024

An ongoing study is assessing the suitability of line pipe materials for use in gaseous hydrogen transmission pipelines. Previous publications present fracture and fatigue testing of the parent and seam weld centre line microstructures of an offshore 1970’s API 5L X60 grade SAW material from a 36″ diameter pipe joint.

This paper offers further results from this study, expanded to include a variety of other materials commonly present in Shell pipelines that are anticipated to be repurposed for use in hydrogen service, tested in near-pure H2 pressures up to 172 bara. This includes the heat affected zone of the same vintage X60 material, a 2010’s era sour rated seamless X65 pipe (SMLS 12″ OD) that has been strained and aged, with tests carried out on both the parent pipe and girth weld, and finally the parent pipe microstructure of a late 1960’s X60 high frequency electric resistance welded pipe sample (HF-ERW, 12″ OD).

The fracture performance of the SMLS material was found to be very similar to the parent pipe of the vintage SAW material in comparing the Kth values, however the slopes of the JR curves were very different after crack initiation. The HF-ERW material showed lower Kth values. Fatigue crack growth results were more similar among the materials and match trends already reported. The impact of the results on hydrogen pipeline design, pipeline reuse, and integrity management is also discussed.
Convert or Not to Convert? Practical Scoping Considerations for Converting Pipelines to Carbon Dioxide Service
Authors: Robertson Nicki , King Graeme , Brimacombe Mark
Published: December 2024

With the move to Net Zero there has been increased demand to utilize pipelines to transport carbon dioxide. As part of these efforts, repurposing hydrocarbon pipelines is an attractive option. The advantages of repurposing existing pipelines rather than building new ones include minimum disturbance to people and the environment, and reduced capital expenditure. While existing documents provide guidance of an overall process to convert, they do not delve into granularity surrounding scoping metrics to screen potential opportunities from impractical applications. Interdependencies of key considerations such as capacity, operating pressure, fluid composition and phase composition will be described with a sequential decision-based methodology proposed.

The purposed methodology is a front-end project screening tool recommended to be used in collaboration with business development prior to investing in detailed engineering evaluations of selected candidate pipelines. This further evaluation is required after screening to evaluate the current state of the asset, define specific flow capacities under both summer and winter conditions, class location assessment, detailed consequence modelling and project risk registry to capture all risks. Cost considerations applicable to the detailed assessment will be discussed to support high level assessment of project viability.

Examples of typical hydrocarbon pipelines in Alberta are provided to demonstrate the application of the methodology in scoping potential conversion projects. From these examples, it is evident that conversion to gas phase service is typically feasible whereas there are fewer pipelines capable of conversion to dense phase service. Even with conversion being technical feasible, the project must be commercially viable. Gas phase conversion candidates may struggle to meet capacity demands. Whereas, dense phase conversion candidates may be hindered by additional costs associated with modifications identified in detailed engineering. The final decision on whether to convert or not to convert depends on accurate detailed assessments of all the details including the cost of the assessment itself. This paper provides an approach to screen projects for viability before undertaking detailed engineering assessments to provide a more tactical approach to building out carbon dioxide pipeline networks.
Managing Pipelines’ Total Stress Landscape With Advancements in In-Line Inspection-Based Bi-Axial Stress Measurement Technology
Authors: ElSeify Mohamed , Buttle David , Worthington Steve , Yablonskikh Inessa
Published: December 2024

Over 15 years ago, pipeline operators requested the development of an in-line inspection (ILI) axial strain measurement tool to support their geohazard management programs. Since then, Axial Strain Measurement Inspection Service (AXISS™) has been employed on over 25,000kms of pipeline with many high strain locations successfully identified and mitigated. Like any new technology, it took the axial strain tool a few years to become a unique, established and proven tool for a pipeline operator to assess geohazards, movement and other strain-related threats.

Over the years, the operators’ experience has provided key insights as to where the current technology strengths lie and of course where enhancement with additional information could further enhance their integrity engineer’s more complete understanding of stress and strain-based threats to then develop proactive mitigation strategies and importantly conduct more cost-effective repair programs — ensuring their pipeline’s safe and continuing operation.

This paper presents a response to these learned and clearly defined needs. It introduces a new bi-axial stress measurement inspection technology AXISS™ EPS that adopts these needed advancements by providing detailed information on the entire stress landscape of both active loading and residual stresses. This proprietary sensing technology used by this new tool is an evolution of a mature stress measurement technique that has successfully delivered bi-axial stress measurements for steel structures for the last 3 decades in a range of industries including flexible pipeline riser systems in the offshore oil and gas industry as well as nuclear, automotive, aerospace and rail.

This paper provides a comprehensive overview of the new bi-axial stress tool technology, its rigorous validation and test results. In addition to that, it gives an insight to some of the novel and unique capabilities it provides to further discriminate the criticality of the pipeline stress condition at any given location along the pipeline driving necessary and timely repair. Furthermore, comparison of this new bi-axial stress/strain data relative to the earlier axial strain inspection data is possible and demonstration of these new capabilities will be described as to benefits it will provide in efficiently and effectively managing pipeline strain-based threats.
Evaluation of an Operator’s Horizontal Directional Drilling Pipeline Installation Inventory and Recommended Practices
Authors: Babcock Joel , Kushner David , Charlesworth Coleby , Dewar Doug
Published: December 2024

Horizontal directional drilling (HDD) is a common pipeline installation method increasingly preferred to avoid challenging terrain, geohazards, and environmentally sensitive areas that would otherwise be encountered with conventionally trenched installations. However, HDD pipeline installations (HDDPIs) are not always designed to avoid geohazard threats, with pipelines often drilled through areas vulnerable to watercourse floodplain erosion or landslides. This can increase pipeline susceptibility to failure up to 15 times compared to conventionally trenched pipelines [1]. Failure to adequately design for, monitor, assess and manage geohazard threats to HDDPIs has resulted in failures, environmental impacts, lengthy pipeline outages and costly HDDPI replacements.

This paper presents an operator’s review of 429 HDDPIs and a proposed standard for classifying, evaluating, monitoring, and mitigating landslide and watercourse threats to both planned and existing HDDPIs. Geotechnical HDDPI hazard sites are classified and assessed by drill path position and ground/pipeline monitoring. Hydrotechnical HDDPI hazard sites are reviewed based on depth of cover, historical air photos, and river geomorphology, and categorized according to likelihood of failure based on potential free span length as related to river size, and estimated time to pipeline exposure. Depending on categorizations, various ground and pipeline monitoring, investigations, and mitigations are prescribed.
Reduction of Methane Leaks Through Corrosion Mitigation Pre-Treatments for Pipelines With Field Applied Coatings
Authors: Lee Kenneth Y. , Thompson Neil G. , Taylor Christopher , Evans Kenneth , Land Jason , Sridhar Narasi , Matocha Garry
Published: December 2024

Corrosion of buried, coated steel pipelines transporting natural gas is a significant source of methane emissions, from pipeline venting required for maintenance and repairs and from pipeline leaks and incidents. Corrosion of steel under field applied coatings is an important safety concern for the pipeline industry. This project investigates the application of a field applied alloy over girth welds to mitigate external corrosion of buried coated steel pipelines.

Various metallic coating options were considered, which were required to meet several criteria: (1) it must resist corrosion under open-circuit or mild cathodic protection conditions, (2) it must protect the substrate steel, and (3) it must not negatively affect the adhesion of the field coating. Finite element models and lab testing were performed of alloy coating compositions to identify promising alloy types underneath disbonded coatings. Polarization curves of coating alloys were generated to provide the boundary conditions for the COMSOL model to compute potential and current distributions around coated areas.

Sacrificial and corrosion-resistant metal alloy coatings were evaluated and optimized using corrosion modeling and laboratory electrochemical testing, where aluminum alloy 5356 (5% Mg) and steel alloy B9 (9% Cr) were selected. Corrosion test coupons were designed and fabricated using flame-sprayed aluminum 5356 and welded B9 steel overlays on API 5L grade X42 line pipe steel. The corrosion test coupons, with simulated pipe coating damage, were tested in a laboratory soil box and a field pipeline site in Texas for 3-months. Corrosion test coupons were then tested for 6-months at field pipeline sites in Texas and Tennessee to quantify corrosion rates and performance of the aluminum and steel alloys under polyethylene tape and 2-part epoxy coatings, various coating holidays, and with and without cathodic protection.
Advancing Leak Detection in Natural Gas Pipelines: A Novel Approach Using Real-Time Transient Modeling for Methane Emissions Mitigation
Authors: Ghasvari-Jahromi Hamed , Ekram Fatemeh , Mokamati Satya
Published: December 2024

Currently, methane emissions account for approximately 25% of human-induced global warming, with the oil and gas sector ranking among the leading contributors. Early detection of methane leaks in pipelines significantly reduces the greenhouse gases emissions, aiding in the mitigation of adverse economic and environmental consequences associated with climate change. Computational Pipeline Monitoring (CPM) systems, tailored for leak detection, provide continuous pipeline monitoring and offer early identification of leaks while minimizing false alarms. This study harnesses advancements in tracking and estimation methodologies and integrates them with physics-based models to address the intricacies of modeling gas pipelines and introduces a real-time transient model (RTTM) used for leak detection of natural gas pipelines.
Two new Aceria species (Acari: Eriophyidae) from Bostanabad county, Iran
Authors: Lotfollahi Parisa , Maghsoodi Shahin , Jahandideh-Dogijan Javad , Bagheri Mohammad
Published: December 2024

During the survey on eriophyoid mite fauna of Asteraceae plants in Bostanabad county, two new species were found and described: Aceria gundeliae Lotfollahi et Maghsoodi sp. nov. on Gundelia tournefortii L. in Alijan village and Aceria tikmedashiensis Lotfollahi et Maghsoodi sp. nov. on Chrysanthemum indicum L. in Tikmedash Research Center. Both species were vagrant on their host plants and are the first records of eriophyoid mites on their host plant genera.
Injuries caused by phytophagous mites on apple trees (Malus domestica: Rosaceae)
Authors: Rode Priscila de Andrade , Schneider Julia Renata , Mariano Cristina Jardim Cezar , Matthes Ronice Drebel , Ferla Noeli Juarez
Published: December 2024

This study aimed to assess the injuries caused by phytophagous mites at different population levels on apple tree leaves (Malus domestica: Rosaceae). The response to different infestation levels of Panonychus ulmi (Koch), Tetranychus urticae Koch and Tetranychus ludeni Zacher (Tetranychidae) on apple tree leaves was assessed through A, B, and total chlorophyll indices and membrane stability loss. Leaves infested with T. urticae showed higher chlorophyll loss, while leaves infested by P. ulmi and T. ludeni had decreased chlorophyll averages in densities of 25 mites/leaf and above. The evaluation of membrane stability loss identified T. ludeni as a potential cause of injuries in apple trees. The evaluations indicated that the higher number of mites on the leaf surface, the larger the membrane stability loss. This work warning to the apple production chain for monitoring infestations and preventing a potential threat to culture.