bluuebunny/crossref_metadata_2025 huggingface dataset:
The Impact of Human DNA Glycosylases on the Activity of DNA Polymerase β toward Various Base Excision Repair Intermediates
Authors: Bakman Artemiy S. , Boichenko Stanislav S. , Kuznetsova Aleksandra A. , Ishchenko Alexander A. , Saparbaev Murat , Kuznetsov Nikita A.
Published: June 2023

Base excision repair (BER) is one of the important systems for the maintenance of genome stability via repair of DNA lesions. BER is a multistep process involving a number of enzymes, including damage-specific DNA glycosylases, apurinic/apyrimidinic (AP) endonuclease 1, DNA polymerase β, and DNA ligase. Coordination of BER is implemented by multiple protein–protein interactions between BER participants. Nonetheless, mechanisms of these interactions and their roles in the BER coordination are poorly understood. Here, we report a study on Polβ’s nucleotidyl transferase activity toward different DNA substrates (that mimic DNA intermediates arising during BER) in the presence of various DNA glycosylases (AAG, OGG1, NTHL1, MBD4, UNG, or SMUG1) using rapid-quench-flow and stopped-flow fluorescence approaches. It was shown that Polβ efficiently adds a single nucleotide into different types of single-strand breaks either with or without a 5′-dRP–mimicking group. The obtained data indicate that DNA glycosylases AAG, OGG1, NTHL1, MBD4, UNG, and SMUG1, but not NEIL1, enhance Polβ’s activity toward the model DNA intermediates.
Dynamics of Ex Vivo Mesenchymal Stromal Cell Potency under Continuous Perfusion
Authors: Doshi Aneesha , Erickson Patrick , Teryek Matthew , Parekkadan Biju
Published: June 2023

Mesenchymal stromal cells (MSCs) are a candidate for cell immunotherapy due to potent immunomodulatory activity found in their secretome. Though studies on their secreted substances have been reported, the time dynamics of MSC potency remain unclear. Herein, we report on the dynamics of MSC secretome potency in an ex vivo hollow fiber bioreactor using a continuous perfusion cell culture system that fractionated MSC-secreted factors over time. Time-resolved fractions of MSC-conditioned media were evaluated for potency by incubation with activated immune cells. Three studies were designed to characterize MSC potency under: (1) basal conditions, (2) in situ activation, and (3) pre-licensing. Results indicate that the MSC secretome is most potent in suppressing lymphocyte proliferation during the first 24 h and is further stabilized when MSCs are prelicensed with a cocktail of pro-inflammatory cytokines, IFNγ, TNFα, and IL-1β. The evaluation of temporal cell potency using this integrated bioreactor system can be useful in informing strategies to maximize MSC potency, minimize side effects, and allow greater control for the duration of ex vivo administration approaches.
Endogenous TOM20 Proximity Labeling: A Swiss-Knife for the Study of Mitochondrial Proteins in Human Cells
Authors: Meurant Sébastien , Mauclet Lorris , Dieu Marc , Arnould Thierry , Eyckerman Sven , Renard Patricia
Published: June 2023

Biotin-based proximity labeling approaches, such as BioID, have demonstrated their use for the study of mitochondria proteomes in living cells. The use of genetically engineered BioID cell lines enables the detailed characterization of poorly characterized processes such as mitochondrial co-translational import. In this process, translation is coupled to the translocation of the mitochondrial proteins, alleviating the energy cost typically associated with the post-translational import relying on chaperone systems. However, the mechanisms are still unclear with only few actors identified but none that have been described in mammals yet. We thus profiled the TOM20 proxisome using BioID, assuming that some of the identified proteins could be molecular actors of the co-translational import in human cells. The obtained results showed a high enrichment of RNA binding proteins close to the TOM complex. However, for the few selected candidates, we could not demonstrate a role in the mitochondrial co-translational import process. Nonetheless, we were able to demonstrate additional uses of our BioID cell line. Indeed, the experimental approach used in this study is thus proposed for the identification of mitochondrial co-translational import effectors and for the monitoring of protein entry inside mitochondria with a potential application in the prediction of mitochondrial protein half-life.
Influence of Estrus on Dairy Cow Milk Exosomal miRNAs and Their Role in Hormone Secretion by Granulosa Cells
Authors: Liu Wenju , Du Chao , Nan Liangkang , Li Chunfang , Wang Haitong , Fan Yikai , Zhou Ao , Zhang Shujun
Published: June 2023

Estrus is crucial for cow fertility in modern dairy farms, but almost 50% of cows do not show the behavioral signs of estrus due to silent estrus and lack of suitable and high-accuracy methods to detect estrus. MiRNA and exosomes play essential roles in reproductive function and may be developed as novel biomarkers in estrus detection. Thus, we analyzed the miRNA expression patterns in milk exosomes during estrus and the effect of milk exosomes on hormone secretion in cultured bovine granulosa cells in vitro. We found that the number of exosomes and the exosome protein concentration in estrous cow milk were significantly lower than in non-estrous cow milk. Moreover, 133 differentially expressed exosomal miRNAs were identified in estrous cow milk vs. non-estrous cow milk. Functional enrichment analyses indicated that exosomal miRNAs were involved in reproduction and hormone-synthesis-related pathways, such as cholesterol metabolism, FoxO signaling pathway, Hippo signaling pathway, mTOR signaling pathway, steroid hormone biosynthesis, Wnt signaling pathway and GnRH signaling pathway. Consistent with the enrichment signaling pathways, exosomes derived from estrous and non-estrous cow milk both could promote the secretion of estradiol and progesterone in cultured bovine granulosa cells. Furthermore, genes related to hormonal synthesis (CYP19A1, CYP11A1, HSD3B1 and RUNX2) were up-regulated after exosome treatment, while exosomes inhibited the expression of StAR. Moreover, estrous and non-estrous cow-milk-derived exosomes both could increase the expression of bcl2 and decrease the expression of p53, and did not influence the expression of caspase-3. To our knowledge, this is the first study to investigate exosomal miRNA expression patterns during dairy cow estrus and the role of exosomes in hormone secretion by bovine granulosa cells. Our findings provide a theoretical basis for further investigating milk-derived exosomes and exosomal miRNA effects on ovary function and reproduction. Moreover, bovine milk exosomes may have effects on the ovaries of human consumers of pasteurized cow milk. These differential miRNAs might provide candidate biomarkers for the diagnosis of dairy cow estrus and will assist in developing new therapeutic targets for cow infertility.
Comprehensive Insight into Colorectal Cancer Metabolites and Lipids for Human Serum: A Proof-of-Concept Study
Authors: Bhatt Kinjal , Orlando Titziana , Meuwis Marie-Alice , Louis Edouard , Stefanuto Pierre-Hugues , Focant Jean-François
Published: June 2023

Colorectal cancer (CRC) ranks as the third most frequently diagnosed cancer and the second leading cause of cancer-related deaths. The current endoscopic-based or stool-based diagnostic techniques are either highly invasive or lack sufficient sensitivity. Thus, there is a need for less invasive and more sensitive screening approaches. We, therefore, conducted a study on 64 human serum samples representing three different groups (adenocarcinoma, adenoma, and control) using cutting-edge GC×GC–LR/HR-TOFMS (comprehensive two-dimensional gas chromatography coupled with low/high-resolution time-of-flight mass spectrometry). We analyzed samples with two different specifically tailored sample preparation approaches for lipidomics (fatty acids) (25 μL serum) and metabolomics (50 μL serum). In-depth chemometric screening with supervised and unsupervised approaches and metabolic pathway analysis were applied to both datasets. A lipidomics study revealed that specific PUFA (ω-3) molecules are inversely associated with increased odds of CRC, while some PUFA (ω-6) analytes show a positive correlation. The metabolomics approach revealed downregulation of amino acids (alanine, glutamate, methionine, threonine, tyrosine, and valine) and myo-inositol in CRC, while 3-hydroxybutyrate levels were increased. This unique study provides comprehensive insight into molecular-level changes associated with CRC and allows for a comparison of the efficiency of two different analytical approaches for CRC screening using same serum samples and single instrumentation.
In Vitro-Produced Equine Blastocysts Exhibit Greater Dispersal and Intermingling of Inner Cell Mass Cells than In Vivo Embryos
Authors: Umair Muhammad , Scheeren Veronica Flores da Cunha , Beitsma Mabel M. , Colleoni Silvia , Galli Cesare , Lazzari Giovanna , de Ruijter-Villani Marta , Stout Tom A. E. , Claes Anthony
Published: June 2023

In vitro production (IVP) of equine embryos is increasingly popular in clinical practice but suffers from higher incidences of early embryonic loss and monozygotic twin development than transfer of in vivo derived (IVD) embryos. Early embryo development is classically characterized by two cell fate decisions: (1) first, trophectoderm (TE) cells differentiate from inner cell mass (ICM); (2) second, the ICM segregates into epiblast (EPI) and primitive endoderm (PE). This study examined the influence of embryo type (IVD versus IVP), developmental stage or speed, and culture environment (in vitro versus in vivo) on the expression of the cell lineage markers, CDX-2 (TE), SOX-2 (EPI) and GATA-6 (PE). The numbers and distribution of cells expressing the three lineage markers were evaluated in day 7 IVD early blastocysts (n = 3) and blastocysts (n = 3), and in IVP embryos first identified as blastocysts after 7 (fast development, n = 5) or 9 (slow development, n = 9) days. Furthermore, day 7 IVP blastocysts were examined after additional culture for 2 days either in vitro (n = 5) or in vivo (after transfer into recipient mares, n = 3). In IVD early blastocysts, SOX-2 positive cells were encircled by GATA-6 positive cells in the ICM, with SOX-2 co-expression in some presumed PE cells. In IVD blastocysts, SOX-2 expression was exclusive to the compacted presumptive EPI, while GATA-6 and CDX-2 expression were consistent with PE and TE specification, respectively. In IVP blastocysts, SOX-2 and GATA-6 positive cells were intermingled and relatively dispersed, and co-expression of SOX-2 or GATA-6 was evident in some CDX-2 positive TE cells. IVP blastocysts had lower TE and total cell numbers than IVD blastocysts and displayed larger mean inter-EPI cell distances; these features were more pronounced in slower-developing IVP blastocysts. Transferring IVP blastocysts into recipient mares led to the compaction of SOX-2 positive cells into a presumptive EPI, whereas extended in vitro culture did not. In conclusion, IVP equine embryos have a poorly compacted ICM with intermingled EPI and PE cells; features accentuated in slowly developing embryos but remedied by transfer to a recipient mare.
Integrative Taxonomy of the Gall Mite Nothopoda todeica n. sp. (Eriophyidae) from the Disjunct Afro-Australasian Fern Todea barbara: Morphology, Phylogeny, and Mitogenomics
Authors: Chetverikov Philipp E. , Craemer Charnie , Gankevich Vladimir D. , Zhuk Anna S.
Published: June 2023

Eriophyoidea is a group of phytoparasitic mites with poorly resolved phylogeny. Previous studies inferred Eriophyidae s.l. as the largest molecular clade of Eriophyoidea, and Nothopodinae as the basal divergence of Eriophyidae s.l. We investigate the morphology and molecular phylogeny of Nothopoda todeica n. sp. (Nothopodinae, Nothopodini), associated with a disjunct Afro-Australasian fern Todea barbara (Osmundaceae) from South Africa. Our analyses (1) determine new erroneous sequences (KF782375, KF782475, KF782586) wrongly assigned to Nothopodinae instead of Phyllocoptinae, (2) confirm the basal position of Nothopodinae in Eriophyoidea s.l., (3) question the monophyly of the Colopodacini and Nothopodini tribes, and (4) show the nested position of African fern-associated Nothopoda within a clade dominated by Asian nothopodines from angiosperms, which implies (a) a secondary association of nothopodines with ferns and (b) no relation between geography (continents) and the phylogenetic relationships of Nothopodinae species. Finally, we obtained a first complete mitochondrial genome for Nothopodinae and revealed a new gene order in the mitogenome of N. todeica n. sp., notably deviating from those in other investigated eriophyoids. Our results contribute to resolving the phylogeny of Eriophyoidea and provide an example of an integrative study of a new taxon belonging to an economically important group of acariform mites.
Identification and Expression Profiling of the 5-HT Receptor Gene in Harmonia axyridis
Authors: Zhang Qiqi , Chang Yifang , Zheng Changying , Sun Lijuan
Published: June 2023

It has been found that 5-hydroxytryptamine (5-HT) modulates the feeding of some insects, and this phenomenon was found in Harmonia axyridis (Pallas) by our previous study. An understanding of the 5-HT system in this beetle is helpful for utilizing 5-HT to modulate its predation to improve biological control efficiency, especially in greenhouses in winter in north China. This is because 5-HT influences diapause in insects by modulating the synthesis and release of prothoracic hormone (PTTH) and, therefore, influences feeding. To elucidate the molecular basis of the H. axyridis 5-HT system, reverse-transcription polymerase chain reaction (RT-PCR), multiple sequence alignment, and phylogenetic tree construction were used to identify the 5-HT receptor in H. axyridis, and quantitative real-time PCR (qRT-PCR) was used to analyze the expression pattern of these receptor genes in different developmental stages and in the nervous system (brain + ventral nerve cord), digestive tract, pectoral muscles, and gonads of the adult ladybird. The results showed that four 5-HT receptors were identified in H. axyridis, named 5-HT1AHar, 5-HT1BHar, 5-HT2Har, and 5-HT7Har. The four receptors were expressed at high levels in the adult stage, especially in 2-day-old adults, with expression levels of 18.72-fold (male) and 14.21-fold (female) of that in eggs for 5-HT1A, 32.27-fold (male) and 83.58-fold (female) of that in eggs for 5-HT1B, 36.82-fold (male) and 119.35-fold (female) of that in eggs for 5-HT2, and 165.47-fold (male) and 115.59-fold (female) of that in eggs for 5-HT7. The level of expression decreased with the advance of day-age in adults. The levels of expression of 5-HT1BHar, 5-HT2Har, and 5-HT7Har were low at the egg, larval, and pupal stages, and 5-HT1AHar was not expressed in the larval stage. The four receptors were expressed in the nervous system, digestive tract, pectoral muscles, and male and female gonads. The 5-HT1AHar was expressed at a high level in the pectoral muscle (6.75-fold of that in the nervous system), 5-HT1BHar in male gonads (1.02-fold of that in the nervous system) and the nervous system, 5-HT2Har in male gonads (5.74-fold of that in the nervous system), and 5-HT7Har in the digestive tract (1.81-fold of that in the nervous system). The results of this study will lay a foundation for research on the function of the 5-HT receptor by RNA interference in the regulation of predation by H. axyridis.
Optimizing Sampling Technique Parameters for Increased Precision and Practicality in Annual Bluegrass Weevil Population Monitoring
Authors: de Sousa Ana Luiza Viana , Kostromytska Olga S. , Wu Shaohui , Koppenhöfer Albrecht M.
Published: June 2023

The annual bluegrass weevil (ABW), Listronotus maculicollis (Kirby), a significant pest of short-mown turfgrass in eastern North America, has developed widespread insecticide resistance because of excessive synthetic insecticide use. The proper monitoring of this pest may reduce insecticide applications in time and space. This study evaluated three sampling methods (soap flushing, vacuuming, and mowing) in golf course greens and fairways for monitoring adult ABW. Soap flushing was the most efficient method, especially with an 0.8% solution in two portions of 500 mL, extracting over 75% of the adults, and the extraction efficiency was not affected by the temperature or time of day. Vacuuming was more effective for recovering adult ABWs on greens (4–29% extracted) than on fairways (2–4%) but was not affected by the time of day. The extraction of adult ABWs in mower clippings was significantly affected by mowing height (higher recovery from greens versus fairways), and the efficiency decreased with the temperature. Adding a brush to the mower increased adult removal (from 15% to 24%) in greens at higher temperatures (18–25 °C); 70% of adults recovered in the clippings were unharmed. Overall, our findings suggest that soap flushing should be the preferred method for monitoring adult ABWs, and vacuuming might be a viable alternative for greens.
Augmented or Mixed Reality Enhanced Head-Mounted Display Navigation for In Vivo Spine Surgery: A Systematic Review of Clinical Outcomes
Authors: Móga Kristóf , Hölgyesi Áron , Zrubka Zsombor , Péntek Márta , Haidegger Tamás
Published: June 2023

Background: This research paper provides a systematic literature review (SLR) on the current status of augmented-reality head-mounted devices (AR-HMDs) that guide and navigate spine surgeries and pedicle screw placement. Methods: Embase, Scopus, PubMed, Cochrane Library and IEEE Xplore databases were screened for the systematic literature search to collect and statistically analyze live patient clinical, procedural and user experience data. Multi-level Poisson and binominal models were used for analysis. Results: In vivo patient data, only the clinically widely used Gertzbein–Robbins Scale, were published as an outcome in the recent heterogeneous literature. The statistical analysis supports the hypothesis that using AR-HMDs has the same clinical outcomes as using more expensive robot-assisted surgical (RAS) systems. Conclusions: AR-HMD-guided pedicle screw insertion is reaching its technology readiness, providing similar benefits to RAS. Further meta-analysis is expected in the future from higher case-numbered and standardized randomized clinical trials.
Mitral Valve Repair in Advanced Age Groups: Does Cardiac Age Differ from Chronological Age?
Authors: Ostovar Roya , Schröter Filip , Hartrumpf Martin , Kuehnel Ralf-Uwe , Bruch Dunja , Motazedian Farnoosh , Albes Johannes Maximilian
Published: June 2023

Objective: Advanced age is a risk factor in cardiac surgery contributing significantly to a worse outcome. The reasons are frailty and multimorbidity. In this study, we asked: Is there an aging of the heart which differs from chronological age? Methods: Propensity score matching was performed between 115 seniors ≥ 80 years and 345 juniors < 80 years. After the patients were found to be comparable in terms of cardiac and noncardiac disease and risk profiles, they were further analyzed for cardiac parameters. In addition, the seniors and juniors were compared in terms of cardiac health and postoperative outcome. Furthermore, the patients were subdivided into several age groups (<60 years, 60–69 years, 70–79 years, and >80 years) and compared regarding outcome. Results: The seniors demonstrated significantly lower tricuspid annular plane systolic excursion (TAPSE), significantly more frequent diastolic dysfunction, significantly higher plasma levels of NT-proBNP, and significantly larger left ventricular end-diastolic and end-systolic diameters and left atrial diameters (p < 0.001, respectively). Furthermore, in-hospital mortality and most postoperative complications were significantly higher in seniors compared with juniors. While old cardiac healthy patients showed better outcome than old cardiac aged patients, the outcome from young cardiac aged patients was better than old cardiac aged patients. The outcome and survival deteriorated with increasing life decades. Conclusions: The elderly suffer significantly more from cardiac deterioration, i.e., cardiac aging, and show higher multimorbidity. Mortality risk is significantly higher and they suffer more often from a complicated postoperative course compared to younger patients. Further approaches to prevention and treatment of cardiac aging are needed to address the needs of an aging society.
Associations of Serum CXCL12α and CK Levels with Skeletal Muscle Mass in Older Adults
Authors: Chen Ze , Laurentius Thea , Fait Yvonne , Müller Aline , Mückter Eva , Bollheimer Leo Cornelius , Nourbakhsh Mahtab
Published: June 2023

Sarcopenia, a condition characterized by gradual loss of skeletal muscle mass and function, is a complex diagnosis; the decisive criterion in this diagnosis is the measurement of appendicular skeletal muscle index (ASMI). To identify potential serum markers predictive of sarcopenia in older adults, we evaluated correlations between ASMI, clinical data, and 34 serum inflammation markers in 80 older adults. Pearson’s correlation analyses confirmed that ASMI was positively correlated with nutritional status (p = 0.001) and serum creatine kinase (CK) (p = 0.019) but negatively correlated with serum CXCL12α (p = 0.023), a chemoattractant for muscle stem cells. In the case group, ASMI was negatively correlated with serum interleukin (IL)-7 (p = 0.024), a myokine expressed and secreted from skeletal muscle cells in vitro. Multivariate binary logistic regression analyses identified four risk factors for sarcopenia in our study: advanced age (p = 0.012), malnutrition (p = 0.038), low serum CK levels (p = 0.044), and high serum CXCL12α levels (p = 0.029). Low CK and high CXCL12α levels serve as combinatorial serum markers of sarcopenia in older adults. The linear correlation between ASMI and CXCL12α levels may facilitate the development of new regression models for future studies on sarcopenia.
Structure and Properties of Polystyrene-Co-Acrylonitrile/Graphene Oxide Nanocomposites
Authors: Mohammadsalih Zaid G. , Inkson Beverley J. , Chen Biqiong
Published: June 2023

Polymer/graphene nanocomposites have attracted significant attention from the research community over the past two decades. In this work, nanocomposites of polystyrene-co-acrylonitrile (SAN) and graphene oxide (GO) were prepared using a solution blending method with tetrahydrofuran as the solvent. The GO loadings used were 0.1, 0.25, 0.5, and 1.0 wt.%. Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy were employed to characterize the structure and morphology of SAN/GO nanocomposites. Thermal analysis showed increases in the glass transition (Tg) and peak thermal degradation (Tdpeak) temperatures of SAN by the additions of GO, with Tg increasing by 3.6 °C and Tdpeak by 19 °C for 1.0 wt.% GO loading. Dynamic mechanical analysis revealed that the storage modulus of SAN was also enhanced with the incorporations of GO by up to 62% for 1.0 wt.% loading. These property enhancements may be attributed to a good dispersion of GO in the polymer matrix and their interfacial interactions.
An Evaluative Review of Barriers to Critical Thinking in Educational and Real-World Settings
Authors: Dwyer Christopher P.
Published: June 2023

Though a wide array of definitions and conceptualisations of critical thinking have been offered in the past, further elaboration on some concepts is required, particularly with respect to various factors that may impede an individual’s application of critical thinking, such as in the case of reflective judgment. These barriers include varying levels of epistemological engagement or understanding, issues pertaining to heuristic-based thinking and intuitive judgment, as well as emotional and biased thinking. The aim of this review is to discuss such barriers and evaluate their impact on critical thinking in light of perspectives from research in an effort to reinforce the ‘completeness’ of extant critical thinking frameworks and to enhance the potential benefits of implementation in real-world settings. Recommendations and implications for overcoming such barriers are also discussed and evaluated.
Effects of Friction Stir Welding Process Control and Tool Penetration on Mechanical Strength and Morphology of Dissimilar Aluminum-to-Polymer Joints
Authors: Correia Arménio N. , Santos Paulo A. M. , Braga Daniel F. O. , Baptista Ricardo , Infante Virgínia
Published: June 2023

An engineering grade polymer—glass fiber-reinforced polyphenylene ether blended with polystyrene—and an aluminum alloy—AA6082-T6—were joined by friction stir welding in an overlap configuration. A comprehensive analysis was conducted of the effects of the tool penetration by adjusting the pin length and the process control on the joints’ mechanical performance. To this end, a series of welds with a fixed 3° tilt angle, a travel speed of 120 mm/min, and 600 RPM of rotational speed was carried out. The analysis encompassed the mechanical strength of the fabricated joints and the mechanical energy input throughout the joining processes, the resulting cross-sectional interfaces, both on macro and micro scales, and the observed defects. The quasi-static shear tensile tests resulted in average tensile strengths varying between 5.5 and 26.1 MPa, representing joint efficiencies ranging from 10.1% to 47.4%, respectively. The joints that exhibited the lowest mechanical performance were fabricated with the highest level of tool penetration (higher pin length) with the process being position-controlled, while the best performance was recorded in joints welded with the lowest tool penetration and a force-controlled process. Nonetheless, the joint welded with a 2 mm long pin and position-controlled process exhibited a mechanical strength comparable with the highest one with a significantly lower standard deviation, a promising attribute for technological industrialization. In this way, it was found that the tool penetration, controlled by adjusting the pin length, played a significant role in the development of the joints’ morphology and, consequently, mechanical performance, whereas the process control exhibited a minor influence on the mechanical performance of the joints, but a considerable effect on process repeatability.
Characterization of the Fracture Forming Limits by Radial Extrusion
Authors: Sampaio Rui F. V. , Pragana João P. M. , Bragança Ivo M. F. , Silva Carlos M. A. , Nielsen Chris V. , Martins Paulo A. F.
Published: June 2023

This paper introduces a new formability test based on double-action radial extrusion to characterize material formability in the three-dimensional to plane-stress material flow transitions that are found in bulk metal-formed parts. The presentation draws from a multidirectional tool, which was designed to convert the vertical press stroke into horizontal movement of the compression punches towards each other, aspects of experimental strain determination, fractography, and finite element analysis. Results show that three-dimensional to plane-stress material flow transitions at the radially extruded flanges lead to different modes of fracture (by tension and by shear) that may or may not be preceded by necking, such as in sheet metal forming. The new formability test also reveals adequate characteristics to characterize the failure limits of very ductile wrought and additively manufactured metallic materials, which cannot be easily determined by conventional upset compression tests, and to facilitate the identification of the instant of cracking and of the corresponding fracture strains by combination of the force vs. time evolutions with the in-plane strains obtained from digital image correlation.
Optimal Design of Flow Control Fins for a Small Container Ship Based on Machine Learning
Authors: Lee Min-Kyung , Lee Inwon
Published: June 2023

In this study, the optimal design of flow control fins (FCFs) for a container ship was carried out via a machine learning approach. The conventional design practice for the FCF relied on simulation-based performance evaluation, which demands a large amount of analysis time. Instead of computational fluid dynamics (CFD)-based prediction, artificial neural network (ANN)-based prediction was attempted. Prior to the machine learning process, the wake distribution data were collected systematically via CFD. Based on the collected data, the wake distributions and resistance performance dependent on varying the fin positions were learned using the ANN, and the optimal fin position was selected with relevant optimization techniques. When multi-objective optimization was employed, it was found that both wake distributions and resistance performance were improved in a practically applicable timeframe. The current process is superior to conventional simulation-based optimization in terms of speed. From the viewpoint of prediction accuracy, in this study, ANN-based prediction was found to be equally accurate as CFD-based prediction. Thus, the results can provide a novel and reliable design methodology for the optimal design of ship appendages.
Ocean Surface Gravity Wave Evolution during Three Along-Shelf Propagating Tropical Cyclones: Model’s Performance of Wind-Sea and Swell
Authors: Hsu Chu-En , Hegermiller Christie A. , Warner John C. , Olabarrieta Maitane
Published: June 2023

Despite recent advancements in ocean–wave observations, how a tropical cyclone’s (TC’s) track, intensity, and translation speed affect the directional wave spectra evolution is poorly understood. Given the scarcity of available wave spectral observations during TCs, there are few studies about the performance of spectral wave models, such as Simulating Waves Nearshore (SWAN), under various TC scenarios. We combined the National Data Buoy Center observations and numerical model hindcasts to determine the linkages between wave spectrum evolution and TC characteristics during hurricanes Matthew 2016, Dorian 2019, and Isaias 2020. Five phases were identified in the wave spectrogram based on the normalized distance to the TC, the sea–swell separation frequency, and the peak wave frequency, indicating how the wave evolution relates to TC characteristics. The wave spectral structure and SWAN model’s performance for wave energy distribution within different phases were identified. The TC intensity and its normalized distance to a buoy were the dominant factors in the energy levels and peak wave frequencies. The TC heading direction and translation speed were more likely to impact the durations of the phases. TC translation speeds also influenced the model’s performance on swell energy. The knowledge gained in this work paves the way for improving model’s performance during severe weather events.
Study and Discussion on Computational Efficiency of Ice–Structure Interaction by Peridynamic
Authors: Zhang Yuan , Zhang Guoyang , Tao Longbin , Wang Chao , Ye Liyu , Sun Shuai , Han Kang
Published: June 2023

The peridynamic (PD) theory is based on nonlocal mechanics and employs particle discretization in its computational domain, making it advantageous for simulating cracks. Consequently, PD has been applied to simulate ice damage and ice–structure interaction under various conditions. However, the calculation efficiency of PD, similar to other meshless methods, is constrained by the number of particles and the inherent limitations of the method itself. These constraints hinder its potential for further development in the field of ice−structure interaction. This study aims to explore the computational efficiency of various methods that can be employed to improve the computational cost of PD in ice–structure interactions. Specifically, we analyze the computational efficiency of three different methods (the MPI parallelization, the updated link−list search method, and the particle−pair method) and their collaborative calculation efficiency to reduce simulation time. These methods are employed to calculate ice–ship interaction, and their coupled efficiency is studied. Furthermore, this study discusses the computation strategy to improve efficiency on using the PD method to calculate ice–structure interaction. The present work provides scholars who employ PD to calculate ice–structure interaction or ice damage with a referential discussion plan to achieve an efficient numerical computation process.
Evaluation of Coastal Protection Strategies at Costa da Caparica (Portugal): Nourishments and Structural Interventions
Authors: Sancho Francisco
Published: June 2023

Costa da Caparica beach, in Portugal, has suffered from chronic erosion for the last 50 years, a phenomenon that has been countered by various management interventions. This study aims at comparing sixteen possible interventions, thus identifying the most effective one(s) in terms of reducing beach erosion or even promoting beach accretion. This exercise is achieved using a one-line shoreline evolution model, calibrated with in situ field data, forced by local wave conditions. The target management period is 25 years. In the calibration phase, it is found that the annual mean alongshore net sediment transport along the 24 km sandy coast is variable in direction and magnitude, but it is mostly smaller than ±50 × 103 m3/year. This net transport results from the imbalance of northward/southward-directed bulk transports of circa tenfold-larger magnitudes. This affects the overall sediment balance at the urban beaches, as well as the effectiveness of the intervention strategies. The results show that the present management strategy is effective in holding the shoreline position, although deploying the same nourishment volume but over a shorter area could lead to better results. The best solutions, which are capable of promoting beach accretion, implicate the lengthening of the terminal groin at the northern extremity of the beach. The results from this study can support decision makers in identifying the most appropriate management action, not just locally but also at other coastal regions where similar problems persist and the same methodology could be applied.
The Practice and Development of T-Bar Penetrometer Tests in Offshore Engineering Investigation: A Comprehensive Review
Authors: Qiao Huanhuan , Liu Lulu , He Huan , Liu Xiaoyan , Liu Xuening , Peng Peng
Published: June 2023

In recent years, the development of marine hydrocarbon resources has led to an increased demand for research on the marine soil bearing capacity and cyclic loading effect in marine engineering design. Because of the difficulties and high costs involved in obtaining high-quality soil samples from offshore sites, in situ testing techniques have become the preferred method of determining design parameters in offshore geotechnical engineering projects. This paper provides a review of the current state of marine penetrometer deployment technology used in offshore engineering investigations and presents a summary of the T-bar penetrometer test for measuring marine soft clay. The existing literature research on penetration mechanisms, numerical simulations, laboratory experiments, and field tests of the T-bar penetrometer in the field of marine geotechnical engineering are analyzed. Finally, the potential difficulties, challenges, and prospects of the T-bar penetrometer tests are discussed.
Strain Rate-Dependent Mechanical Response of Hydrate-Bearing Sediments under Plane Strain Condition
Authors: Wu Qi , Zhao Yingjie , Yoshimoto Norimasa , Guan Jinan , Nakata Yukio , Kajiyama Shintaro , Hyodo Masayuki
Published: June 2023

Natural gas hydrate has gained significant attention in recent years. To safely and sustainably exploit the natural gas from gas hydrate-bearing sediments, it is crucial to understand the long-term mechanical characteristics of the hydrate reservoir. In this study, the influence of hydrate and fine particles on the strain rate dependence of hydrate-bearing sediments under plane strain conditions has been studied. The experimental results show that the strain rate dependency of the mechanical properties of hydrate-bearing sediments is positively correlated with hydrate saturation instead of the morphology of hydrate in sediments. The residual strength of hydrate-bearing sediments is primarily controlled by the hydrate saturation and is independent of the strain rate. Changes in hydrate saturation and fines content can affect the relationship between the strain rate and shear band angle. Finally, the local volumetric expansion effect of hydrate-bearing sediments without fines content is more significant and shows a strong strain rate dependence characteristic. Overall, this study provides valuable insights into the long-term mechanical characteristics of hydrate reservoirs. These insights can contribute to the development of a constitutive model of hydrate-bearing sediments with time dependence in the future, which is meaningful to the exploitation of natural gas hydrate.
The Aerodynamic Characteristics of a Rotating Cylinder Based on Large-Eddy Simulations
Authors: Zhao Dagang , Zhang Yang , Bi Mingqi , Zheng Xin , Zhong Xianghai , Zhang Shun
Published: June 2023

The cylindrical flow around a cylinder is present in several engineering problems. Moreover, the flow pattern around a rotating cylinder is more complex than that around a cylinder. In this paper, a rotating cylinder at different speed ratios is investigated by means of large-eddy simulations. In particular, the lift coefficient CL, drag coefficient CD, lift-to-drag ratio k, Strouhal number St, the flow field in each section, and the three-dimensional eddy structure are compared at different speed ratios. In addition, the effects of an end disk on the aerodynamic loads and flow field of the rotating cylinder were investigated. The results showed that, in the absence of an end disk, CL increased, CD increased and then decreased, k increased and then decreased, and St increased and then decreased as the speed ratio increased. The turnaround occurs for each parameter at a speed ratio of n = 2, and vortex shedding is suppressed at this speed ratio. Notably, the tip vortex at the free end was not suppressed. The CL, CD, and k values of the cylinder when adding the end disk were greater than those of the normal cylinder. For example, when the speed ratio is 3, the lift coefficient is increased by 27%, the drag coefficient is increased by 24%, and the lift-to-drag ratio is increased by 23% after adding the end plate. In addition, the vortex structure at the free end differed substantially. This study provides a systematic method to evaluate the aerodynamic loads and flow field changes around a cylinder, laying the foundation for solving the problems of cylinder flow and rotating cylinder flow.
Application of Np–Am Mixture in Production of 238Pu in a VVER-1000 Reactor and the Reactivity Effect Caused by Loss-of-Coolant Accident in the Central Np–Am Fuel Assembly
Authors: Shmelev Anatoly N. , Geraskin Nikolay I. , Apse Vladimir A. , Glebov Vasily B. , Kulikov Evgeny G. , Krasnoborodko Andrey A.
Published: June 2023

This paper presents the results obtained from numerical evaluations for the possibility of large-scale 238Pu production in the light-water VVER-1000 reactor and the reactivity effect caused by the loss-of-coolant accident in the central fuel assembly of the reactor core. This fuel assembly containing the Np–Am-component of minor actinides was placed in the center of the reactor core and intended for intense production of 238Pu. Optimal conditions were found for large-scale production of plutonium with an isotope composition suitable for application in radioisotope thermoelectric generators. The reactivity effect from the loss-of-coolant accident in the central Np–Am fuel assembly was evaluated, and the perturbation theory was used to determine the contributions of some neutron processes (leakage, absorption, and moderation) to the total variation of the effective neutron multiplication factor.
Clinically Meaningful Fatigue and Depression Are Associated with Sarcopenia in Patients with Non-Alcoholic Fatty Liver Disease
Authors: Sheptulina Anna F. , Yafarova Adel A. , Golubeva Julia A. , Mamutova Elvira M. , Kiselev Anton R. , Drapkina Oxana M.
Published: June 2023

Background: Sarcopenia is thought to be related to an increased risk of non-alcoholic steatohepatitis and advanced liver fibrosis. Our cross-sectional single-center study was designed to analyze the prevalence of sarcopenia in patients with NAFLD and possible influencing factors. Methods: A survey on the presence of sarcopenia, fatigue, anxiety, and depression, along with a quality-of-life (QoL) assessment, was forwarded by email to 189 outpatients. Demographics, anthropometric and clinical data (laboratory test results and abdomen complete ultrasound protocol), performed within 2–4 weeks prior to the enrollment, were obtained. Results: Sarcopenia (defined as SARC-F score ≥ 4) was identified in 17 (15.7%) patients, all of them (100%) females, with median age (interquartile range) 56 (51–64) years. These patients had a poorer metabolic state (greater values of waist and hip circumferences, body mass index, and HOMA-IR) and significantly poorer QoL, specifically, regarding the physical component of health, compared with NAFLD patients without sarcopenia. Multivariate analysis showed that depression (OR = 1.25, 95% CI: 1.02–1.53, p = 0.035) and clinically meaningful fatigue (OR = 1.14, 95% CI: 1.04–1.26, p = 0.008) were the factors independently associated with sarcopenia in patients with NAFLD. Conclusion: Sarcopenia is associated with depression and fatigue rather than with the severity of liver disease alone and may negatively affect QoL in patients with NAFLD.
Spanish Cross-Cultural Adaptation of the Australian Pelvic Floor Questionnaire
Authors: Medrano-Sánchez Esther M. , Pérez-Carricondo Ana , Beteta-Romero Pilar , Díaz-Mohedo Esther
Published: June 2023

The main objectives of this study were to carry out the translation and cross-cultural adaptation of the Australian Pelvic Floor Questionnaire (APFQ) into Spanish and the evaluation of its psychometric properties of validity and reliability in the Spanish population. The APFQ was translated into Spanish and back-translated into its original language by native speakers; it was verified that there was a semantic similarity. A pilot test was carried out on a group of 10 women. The study sample was made up of 104 subjects. They were asked to fill in the APFQ twice, 15 days apart. Codes were assigned so they could link to the test and retest. The Questionnaire on Pelvic Floor Dysfunctions–short version (PFDI-20) and the Women’s Sexual Function Questionnaire (FSM) were also completed. The reliability, criterion and construct validity, and stability were studied. A Cronbach’s alpha of 0.795 was obtained from the complete questionnaire. For each dimension, Cronbach’s alpha was 0.864 for bladder function; 0.796 for bowel function; 0.851 for prolapse; and 0.418 for sexual function (0.67 with the suppression of item 37). The APFQ shows a significant correlation with PFDI-20 in urinary function (rho: 0.704, p = 0.000), intestinal function (rho: 0.462, p = 0.000), and prolapse symptoms (rho: 0.337, p = 0.000). The test-retest analysis showed high reproducibility. The Spanish version of the APFQ is a reliable and valid tool to assess symptoms and impacts on quality of life due to pelvic floor dysfunctions in the Spanish population. However, a review of some of its items could increase its reliability.
Machine Learning Techniques to Map the Impact of Urban Heat Island: Investigating the City of Jeddah
Authors: Addas Abdullah
Published: June 2023

Over the last decades, most agricultural land has been converted into residential colonies to accommodate the rapid population expansion. Population growth and urbanization result in negative consequences on the environment. Such land has experienced various environmental issues due to rapid urbanization and population increases. Such expansion in urbanization has a big impact on worsening the residences soon and in the long term, as the population is projected to increase more and more. One such issue is the urban heat island (UHI), which is computed based on land surface temperature (LST). The UHI effect has fundamental anthropogenic impacts on local areas, particularly in rapidly growing cities. This is due to the unplanned shifts in land use and land cover (LUALC) at the local level, which results in climate condition variations. Therefore, proper planning based on concrete information is the best policy in the long run to remedy these issues. In this study, we attempt to map out UHI phenomena using machine learning (ML) algorithms, including bagging and random subspace. The proposed research also fulfills the sustainable development goals (SDGs) requirement. We exploit the correlation and regression methods to understand the relationship between biophysical composition and the UHI effect. Our findings indicate that in the megacity of Jeddah, Saudi Arabia, from 2000 to 2021, the urban area enlarged by about 80%, while the UHI increased overall. Impervious surfaces significantly impact the UHI effect, while vegetation and water bodies have negative implications for the UHI effect. More than 80% of the total parts in Jeddah have been classified by extremely high UHI conditions, as determined by the bagging and random subspace models. In particular, the megacity’s south, north, and central-east parts were categorized by very high UHI conditions. This research is not only expected to assist in understanding the spatial patterns of the UHI in Jeddah, but to assist planners and policymakers in spatial planning. It will help to ensure sustainable urban management and improve life quality.
Carbon Emission Effects of Land Use in Chaobai River Region of Beijing–Tianjin–Hebei, China
Authors: Liu Caixia , Xu Rui , Xu Kaiji , Lin Yiwen , Cao Yingui
Published: June 2023

Beijing–Tianjin–Hebei, the main economic area in northern China, has seen significant changes in its regional economic and physical landscape as a result of the coordinated development strategy. Assessing the link between land use and land cover (LULC) change and carbon emissions in the Chaobai River region, which represents the growth of the Beijing–Tianjin–Hebei urban agglomeration, is crucial to achieve coordinated low-carbon development in this area. This study uses statistics from statistical yearbooks of Chinese provinces and cities along with land use change data to analyze the relationship between land use changes and carbon emissions in the Chaobai River region from 2001 to 2017 using dynamic land use attitudes and land use transfer matrices, combined with carbon emission factors based on the IPCC inventory method and carbon emission models for energy consumption. In addition, this study makes use of the LMDI model and geographical detectors to identify and assess the factors that influence changes in land use carbon emissions and the driving forces behind the regional differentiation of land use changes. The results show that: (1) The Chaobai River region’s predominant land use classes during the past 17 years have been agricultural land and construction land. In addition to the decrease in cropland and the increase in urban land, the land use patterns of other land classes also changed to a certain extent. (2) Carbon emissions from land use showed an increasing trend, from 6.1 × 106 tons in 2001 to 1.1 × 107 tons in 2017. (3) Carbon emission intensity, economic development level, land use efficiency, and construction land scale have a certain regularity in the evolution of carbon emissions, and economic development level has become the most important driving factor controlling the growth of land use carbon emissions. (4) Driving factors in different periods have different degrees of influence on land use change, among which socio-economic factors such as population density and GDP have the strongest explanatory power. In addition, the interactions of each factor mainly present a double factor enhancement. In the future, the Chaobai River region should be based on the coordinated development strategy and take the “double carbon” target as its guiding principle to promote the innovation of the regional development system and further achieve the optimization of the regional land use patterns.