bluuebunny/crossref_metadata_2025_split huggingface dataset:
Metallurgical Investigation and Failure Analysis in GTD-111 Stage 2 Buckets From an Industrial F-Class Gas Turbine
Authors: Bridges Alex , Shingledecker John , Wang Yongqing 
Published: November 2024

Abstract
A utility experienced cracking in multiple stage 2 buckets (S2Bs) in a large F-class power generation gas turbine after only 7348 h and 31 starts following a standard repair and rejuvenation heat treatment cycle. The blades were cast from a directionally solidified (DS) superalloy and the cracking was found in the shroud section of the blade in the Z-notch region. A detailed failure investigation was conducted to determine the failure mechanism and most likely contributing factors to root cause in terms of design, operation, fabrication, and metallurgy. Three blades, two with visible cracks and one without cracks, were subjected to nondestructive and destructive evaluation. Methods consisted of visual inspection, three-dimensional scanning, physical measurements, chemical analysis, optical metallography, LED surface topological evaluation, and scanning electron microscopy. The failure mechanism was determined to be due to creep with damage propagating along the grain boundaries in a high stress concentration area. Evaluation of precipitate structure and size also confirmed this area exhibited the highest temperature during operations. High temperature creep testing was also conducted in material from the two different casting houses to confirm metallurgical risk did not have a significant impact on creep performance. An evaluation of the operational profile of an entire fleet of GE 7FA units showed that the failed 7F.03 S2Bs were in the highest operating temperature base loaded units. The findings from this work will help better define key factors that influence the high temperature performance of nickel-base superalloys used in the hot section of industrial power generating turbines.
Performance Optimization of an Axial Compressor Using a Novel Multifidelity Surrogate Model Based on Flow Field Extraction
Authors: Liu Yitong , Gong Wuqi , Li Ya , Wang Yitian 
Published: November 2024

Abstract
During the utilization of efficient optimization algorithms for axial compressors, the construction of a precise performance prediction surrogate model stands as a pivotal step. To reduce the cost of constructing the surrogate model while ensuring prediction accuracy, a novel multifidelity surrogate model based on flow field extraction (FFMFS) is proposed in this paper. In constructing FFMFS, two sets of samples with different fidelity are employed for model training, and six important flow field variables in axial compressors are extracted to modify the performance deviation between low-fidelity (LF) and high-fidelity (HF) results. Based on the proposed FFMFS, the aerodynamic performance of a 1.5-stage subsonic axial compressor is optimized, and the numerical method used in the optimization is validated on a 3.5-stage axial compressor test bench. During optimization, adjustments are made to the rotor blade profile, taking into account a total of 28 design variables and six objective functions. The FFMFS constructed for this compressor demonstrates a high prediction accuracy with a R2 value of 0.96, while also significantly reducing the sample generation cost. The optimization results show that the compressor efficiency and pressure ratio are significantly improved across the entire operating range. As a result of adjusting the rotor blade profile, the flow loss inside the compressor is evidently reduced. This work provides a new framework for constructing MFS with flow field information of axial compressors.
Experiments on Structurally Mistuned UHBR Open-Test-Case Fan ECL5/CATANA
Authors: Brandstetter Christoph , Schneider Alexandra P. , Fiquet Anne-Lise , Paoletti Benoit , Ottavy Xavier 
Published: November 2024

Abstract
The operational capabilities of turbofan engines encounter limitations due to instabilities arising from tightly coupled interactions among aerodynamics, acoustics, and structural mechanics. Modern fans and compressors exhibit non-synchronous vibration (NSV), leading to safety-critical blade oscillations. In contrast to self-excited phenomena such as flutter, NSV stems from the convection of aerodynamic disturbances that synchronize with blade eigenmodes. Understanding this phenomenon is challenging, as its intricate interaction patterns and the occurrence of flow separations constrain the predictive capabilities of current state-of-the-art methods. To establish a comprehensive benchmark dataset on the aeroelastic behavior of modern ultra-high bypass ratio (UHBR) architectures, the European CleanSky-2 project CATANA aimed to examine a carbon composite fan stage, ECL5, utilizing multiphysical instrumentation. Recently, experiments on a structurally tuned reference configuration were conducted, revealing high-amplitude NSV at multiple subsonic speedlines. The observed interaction modes and instability onset differed significantly from numerical predictions using both linearized Reynolds-averaged Navier–Stokes and unsteady Reynolds-averaged Navier–Stokes with prescribed harmonic blade motion. In an effort to enhance the dataset, two additional fan configurations with identical blade profile geometries were investigated: one featured a structurally mistuned rotor with approximately doubled frequency variation of all eigenmodes compared to the reference, and the other involved a case with locally increased tip clearance on individual blades. This paper presents the experimental results of a sensitivity study and explores the influence of structural mistuning and tip clearance variation associated with manufacturing tolerances. Contrary to the intended outcome, it will be demonstrated that the mistuned case exhibited higher blade vibration amplitudes than the reference case during NSV. Detailed instrumentation reveals that the mistuning pattern was effectively transferred to the rotating system, but aerodynamic mistuning, particularly concerning tip clearance, emerged as a dominant factor. The non-synchronous forced-response nature of NSV during highly throttled operation ultimately dictates the observed response levels under different conditions, necessitating a thorough analysis to evaluate the robustness of a specific configuration. These results contribute valuable insights to the open dataset for the ECL5 configuration, benefiting the research community. Particularly noteworthy is the detailed capture of blade-to-blade variations in this research, which will prove instrumental in validating numerical methods.
Evaluation of Subfilter Model Performance for Large-Eddy Simulations of Supercritical Fluids
Authors: Purushotham Dhruv , Oefelein Joseph C. 
Published: November 2024

Abstract
The accuracy of three large-eddy simulations (LES) is assessed using a reference dataset obtained via direct numerical simulation (DNS). All of the LES simulations employ the dynamic Smagorinsky model to close the momentum equation and a dynamic gradient model to close the total energy equation. The LES data are obtained on three grids with resolutions spanning from the wall-resolved LES limit to two successive levels coarser in the spatial and temporal domains. The configuration employed for the study is a three-dimensional spatially evolving turbulent shear layer. The working fluid is pure carbon dioxide. The system is maintained at a supercritical state near the critical point such that the field is dominated by strongly nonlinear thermophysics. This allows the analysis to occur under conditions where the subfilter closures are significantly strained by the thermodynamics. Results explore characteristics of the turbulence from both a modeling and fundamental perspective. First, mixing layer growth rates are quantified. Discrepancies are found between the reference DNS data and the LES data. Energy spectra, turbulent transport coefficients, and Reynolds stress anisotropy results are presented to explore the origins of this mismatch.
Theoretical Analysis of Workspace of a Hybrid Offset Joint
Authors: Peiyi Li , Hasiaoqier Han , Junwei Lin , Liheng Chen , Qingwen Wu , Zhenbang Xu 
Published: November 2024

Abstract
Offset joints are widely used in robotics, and literature has demonstrated that axial offset joints can expand the workspace. However, the hybrid offset joint, which incorporates offsets in three orthogonal directions (x, y, and z axes), provides a more flexible and comprehensive range of motion compared to traditional axial offset joints. Therefore, a comprehensive understanding of the workspace of hybrid offset joints with three-directional offsets is essential. First, through a parameter model, the interference motion of hybrid offset joints is studied, considering three different directional offsets and obtaining analytical expressions. Next, based on coordinate transformations, the workspace of this joint is investigated, resulting in corresponding theoretical formulas. In addition, the influence of offset amounts in various directions on the joint’s workspace is examined. Finally, the application of hybrid offset joints in parallel manipulators (PMs) is introduced, highlighting their practical engineering value. Through comparative analysis, it is found that lateral offsets on the x- and y-axes adjust the maximum rotation angles, while the z-axis offset expands the rotational range of these joints. Moreover, by increasing the limit rotation angle of the passive joint in a specific direction, the application of hybrid offset joints in PMs can impact the workspace. These findings offer valuable insights for the design of hybrid offset joints and their applications in robotics.
Sport- and Nonsport-Related Concussion Reporting Behaviors of Emerging Adults Participating in Organized Sport
Authors: Kerr Zachary Yukio , Pierce Megan N. , Register-Mihalik Johna , Ingram Brittany M. 
Published: November 2024

This study examined concussion-related outcomes among emerging adults (18–24 years) who participated in organized sport and are at risk for both sport-related concussion (SRC) and non-SRC. An online survey on SRC/non-SRC history and reporting behaviors grouped a convenience sample of 146 individuals as: no concussion history, those with only SRCs, and those with ≥1 non-SRC (including those with and without SRCs). Participants also noted whether ≥1 concussions were sustained with medical presence or had delayed reporting to someone in authority (e.g., medical professional, coach, and parent). No differences by concussion history were observed. However, among those with both SRC and non-SRC (n = 20), there were higher odds of ≥1 SRC versus ≥1 non-SRC occurring with medical presence (McNemar odds ratio = 12.0, 95% confidence interval [1.6, 92.3]) and having delayed reporting (McNemar odds ratio = 5.0, 95% confidence interval [0.6, 42.8]). Findings highlight the need for multiple pathways to help at-risk individuals report and seek care for concussions.
Psychosocial Factors on Athlete Return to Sport Readiness After Anterior Cruciate Ligament Reconstruction: A Critically Appraised Topic
Authors: Robinson Kala , Kossman Melissa K. 
Published: November 2024

Clinical Scenario: Anterior cruciate ligament (ACL) injuries are a common injury experienced by athletes and often involve lengthy and invasive treatments. Given the literature that exists supporting psychosocial response to injury, it is important to understand how these factors influence the recovery process ultimately influencing readiness to return to play. Clinical Question: What is the impact of psychosocial factors on athlete readiness to return to sport participation post-ACL reconstruction (ACLR)? Summary of Key Findings: All studies found that psychosocial factors, including athletic identity, motivation, anxiety, control, and fear, impacted perceived readiness to return to play. Several studies found various levels of influence in both a positive (eg, motivation and resilience) and negative (eg, fear and anxiety) direction. Furthermore, despite presenting more psychosocial barriers than physical, these factors do not appear to influence actual physical recovery. Clinical Bottom Line: Psychosocial factors have both direct and indirect effects, positive and negative, on an athlete’s perceived readiness to return to the play. ACLR rehabilitation protocols are well developed, well established, and known to be effective; however, athletes still do not feel ready to return, and there are physical and mental risks associated with that uncertainty. Therefore, psychosocial factors are important to include and prioritize as part of the ACLR recovery process to ensure athletes are physically and psychosocially ready to return to play. Strength of Recommendation: Grade B evidence exists that psychosocial factors positively and negatively impact physical recovery and perceptions of recovery on return-to-play post-ACLR.
Assessing the Knee Extensor’s Rate of Force Development Using a Fixed Handheld Dynamometer: An Inter- and Intrasession Reliability Study
Authors: Yona Tomer , Fischer Arielle G. 
Published: November 2024

Context: The rate of force development (RFD), defined as the ability to rapidly generate muscle force, is commonly tested using an electromechanical dynamometer in isometric mode. However, these devices are expensive and not readily available. Therefore, this study aims to evaluate the interrater reliability of a ﬁxed handheld dynamometer to measure the knee extensors’ RFD and provide reference values using the proposed method. Design: This study used a cross-sectional study design. Methods: Using a fixed handheld dynamometer (microFET2) and a 3-dimensional-printed adapter, we evaluated the knee extensor muscles in participants seated at the edge of a treatment bed. Each participant performed a standardized warm-up, followed by 3 maximal isometric knee extension trials. The outcome measures were peak force and early and late phase RFD (0–100 and 0–200 ms, respectively). The study consisted of 3 sessions: Visit one comprised of an initial session (session 1A) followed by a second session (session 1B) after 30 minutes for intrasession reliability; and visit two, conducted on week later, comprised the third session (session 2) for intersession reliability. Results: Fifty-one participants were enrolled in the study. The in-session intraclass correlation coefficient for the early phase RFD was .87 (95% CI, .74–.92) and .91 to .92 (95% CI, .87–.94) for the late phase. The between-session intraclass correlation coefficient for the early phase RFD was .83 to .86 (95% CI, .74–.91) and .87 to .90 (95% CI, .80–.94) for the late phase. Finally, the peak force’s intraclass correlation coefficient was .95 (95% CI, .92–.97) for the in-session and .91 to .92 (95% CI, .86–.95) for the between-session reliability. Conclusions: Our approach provides a reliable, cost-effective, and quick method to evaluate the knee extensor muscles’ RFD and peak force.
Bacterial interactions underpin worsening lung function in cystic fibrosis-associated infections
Authors: Rivett Damian W. , Hatfield Lauren R. , Gavillet Helen , Hardman Michelle , van der Gast Christopher 
Published: November 2024

ABSTRACT

Chronic lung infections are the primary cause of morbidity and early mortality in cystic fibrosis (CF) and, as such, have been the subject of a great deal of research. Subsequently, they have become one of the key paradigms for polymicrobial infections. The literature, however, has traditionally focused on the presence of pathogens in isolation or univariate measures like number of species to predict decline of lung function and ignores large swathes of data. Here, we suggest that looking at the interactions between species identified by 16S rRNA gene sequencing, rather than at species singularly, could elucidate hitherto unknown properties of these complicated infections. To confirm this, pooled samples from studies conducted by our laboratory, sequenced using the same pipeline, were used to assess microbiome-wide associations to lung function. We found pathogenic interactions between species were limited to the most abundant species, which were composed of canonical CF pathogens (including
Pseudomonas
,
Staphylococcus
,
Stenotrophomonas
, and
Achromobacter
) and commensals. This observation is crucial for better understanding of polymicrobial infections and treatment of these conditions while providing a simple framework for expanding this research into other disease states. The adoption of ecological principles into infection science can provide better understanding and options to those suffering from chronic conditions. The statistical ecology approach presented here enables clear hypotheses from observational data that can be ratified through subsequent manipulative experimental studies. Moreover, it can also be used to support the design and construction of clinically relevant
in vitro
models of polymicrobial infections.

IMPORTANCE
Research studies have repeatedly demonstrated that chronic lung infection in cystic fibrosis is polymicrobial and consequently does not adhere to the single microbe-based Koch’s postulates. Despite the plethora of evidence, the role of the constituent taxa present is largely unknown. Here we demonstrate how an ecological modeling perspective on lung infection microbiota can tease out potential interactions that alter progression of disease. Using techniques akin to genome-wide association studies, we show and validate 22 taxa, present in the chronic respiratory disease associated with cystic fibrosis, which have significant interactions that are negatively associated with patient lung function, the majority of which are “non-pathogenic” organisms. This work highlights the need to understand the interactive landscapes of the microbiomes to fully appreciate the complexity and treat chronic lung infections. Furthermore, this presents testable hypotheses for manipulative experiments in model systems to elucidate key mechanisms to driving disease progression.
Complete genome sequence of
Weissella cibaria
strain CXO-01 isolated from Korean saliva
Authors: Jo HyungWoo , Lee Dong-Geol , Kim Hye-Been , Kim Jungeun , Kang Seunghyun , Mun Seyoung , Karm Myong-Hwan , Kim Hyun Jeong 
Published: November 2024

ABSTRACT

We present the genome sequence of
Weissella cibaria
strain CXO-01, isolated from saliva from one Korean individual and kimchi. The genome consisted of one circular chromosome with a length of 2,371,631  bp, three circular plasmids of 20,579 bp, 4,818  bp, and 4,494 in size. Gene prediction revealed 2,305 genes, 2,157 coding DNA sequences.
Whole-genome sequence of
Ensifer aridi
strain RCAM05007 isolated from
Cyamopsis tetragonoloba
(L.) Taub. root nodule
Authors: Guro Polina , Kuznetsova Irina , Sazanova Anna , Belimov Andrey , Karlov Denis , Safronova Vera 
Published: November 2024

ABSTRACT

We present the genome sequence of
Ensifer aridi
strain RCAM05007 obtained from long reads. The strain was isolated from the root nodule of
Cyamopsis tetragonoloba
(L.) Taub. plant inoculated with a soil sample from India. The assembly contains one chromosome and two megaplasmids totalling ~6.7 Mbp with 61.6% GC content.
Complete genome sequences of toxigenic
Clostridioides difficile
isolated from Australian feral horses
Authors: Hain-Saunders Natasza , Knight Daniel R. , Bruce Mieghan , Riley Thomas V. 
Published: November 2024

ABSTRACT

Recent increases in community-associated
Clostridioides difficile
infections have highlighted the importance of monitoring toxigenic
C. difficile
from animal and environmental sources. We provide the complete circularized genomes of two toxigenic
C. difficile
strains isolated from feral horse faeces. Genome N64 (sequence type 964) consists of a single chromosome of 4,078,791 bp, while genome H251 (sequence type 963) comprises one chromosome (4,304,722 bp) and three plasmids (150,942 bp, 11,534 bp, and 9,074 bp).
Optimized methods for the targeted surveillance of extended-spectrum beta-lactamase-producing
Escherichia coli
in human stool
Authors: Gallichan Sarah , Forrest Sally , Picton-Barlow Esther , McKeown Claudia , Moore Maria , Heinz Eva , Feasey Nicholas A. , Lewis Joseph M. , Graf Fabrice E. 
Published: November 2024

ABSTRACT

Understanding transmission pathways of important opportunistic, drug-resistant pathogens, such as extended-spectrum beta-lactamase (ESBL)-producing
Escherichia coli
, is essential to implementing targeted prevention strategies to interrupt transmission and reduce the number of infections. To link transmission of ESBL-producing
E. coli
(ESBL-EC) between two sources, single-nucleotide resolution of
E. coli
strains, as well as
E. coli
diversity within and between samples, is required. However, the microbiological methods to best track these pathogens are unclear. Here, we compared different steps in the microbiological workflow to determine the impact different pre-enrichment broths, pre-enrichment incubation times, selection in pre-enrichment, selective plating, and DNA extraction methods had on recovering ESBL-EC from human stool samples, with the aim to acquire high-quality DNA for sequencing and genomic epidemiology. We demonstrate that using a 4-h pre-enrichment in Buffered Peptone Water, plating on cefotaxime-supplemented MacConkey agar and extracting DNA using Lucigen MasterPure DNA Purification kit improves the recovery of ESBL-EC from human stool and produced high-quality DNA for whole-genome sequencing. We conclude that our optimized workflow can be applied for single-nucleotide variant analysis of an ESBL-EC from stool.

IMPORTANCE

Drug-resistant infections are increasingly difficult to treat with antibiotics. Preventing infections is thus highly beneficial. To do this, we need to understand how drug-resistant bacteria spread to take action to stop infection and transmission. This requires us to accurately trace these bacteria between different sources. In this study, we compared different laboratory methods to see which worked best for detecting extended-spectrum beta-lactamase (ESBL)-producing
E. coli
, a common cause of urinary tract or bloodstream infections, from human stool samples. We found that enriching stool in a nutrient broth for 4 h, then plating the bacterial suspension on antibiotic-selective MacConkey agar, and finally extracting DNA from the bacteria using a specific DNA purification kit resulted in improved recovery of ESBL
E. coli
and high-quality DNA. Sequencing multiple isolates from stool allowed us to distinguish unambiguously and at high resolution between different variants of ESBL
E. coli
present in stool.