bluuebunny/crossref_metadata_2025 huggingface dataset:
Singing to a Genre: Constraints on Variable Rhoticity in British Americana
Authors: Campos-Astorkiza Rebeka
Published: May 2024

This study focuses on accent shift or stylization to American English features in Anglophone pop-rock music and examines linguistic constraints alongside music-related considerations, as well as the effect of changes in musical genre on variable accent shift. The case study is the British band Mumford and Sons and their variable production of non-prevocalic rhotics as either present or absent. Mumford and Sons is of interest because they have displayed a change in their musical style throughout their career from Americana to alt-rock. The band’s four studio albums were auditorily analyzed and coded for rhotic vs. non-rhotic with aid from spectrograms. The linguistic factors considered were word class, preceding vowel according to the word’s lexical set, complexity of the preceding vowel, syllable complexity, stress, and location within the word and phrase. In addition, the effect of singing-related factors of syllable elongation and rhyming, and of the specific album, were also explored. Results show that rhoticity is favored in content words, stressed contexts, complex syllables, and NURSE words. This pattern is explained as stemming from the perceptual prominence of those contexts based on their acoustic and phonological characteristics. Results further show that syllable elongation leads to more rhoticity and that rhyming words tend to agree in their (non-)rhoticity. Finally, the degree of rhoticity decreases as the band departs from Americana in their later albums, highlighting the relevance of music genre for accent stylization.
Barrier Properties of Cr/Ta-Coated Zr-1Nb Alloy under High-Temperature Oxidation
Authors: Syrtanov Maxim Sergeevich , Korneev Stepan Pavlovich , Kashkarov Egor Borisovich , Sidelev Dmitrii Vladimirovich , Moskvichev Evgeny Nikolaevich , Kudiiarov Viktor Nikolaevich
Published: May 2024

In this paper, Cr (8 μm)/Ta (3 μm) bilayer coatings deposited on a Zr-1Nb alloy substrate were investigated and compared with a Cr-coated alloy under high-temperature steam oxidation at 1200–1400 °C. The bilayer coatings with α- and β-Ta interlayers were obtained by magnetron sputtering. The Cr/Ta-coated samples were studied using scanning electron microscopy (SEM), X-ray diffraction (XRD), and optical microscopy (OM). The coating with an α-Ta interlayer can suppress the interdiffusion of chromium and zirconium more effectively up to 1330 °C in comparison with the coating having a β-Ta interlayer. The weight gain of the α-Ta-coated samples after oxidation at 1200 °C for 2000 s was 5–6 times lower than that of the Cr-coated Zr alloy samples. Oxidation at 1400 °C for 120 s showed no significant difference in the weight gain of the Cr- and Cr/Ta-coated Zr-1Nb alloy samples. It was shown that the effect of suppression of Zr-Cr interdiffusion by the barrier coating (α- and β-Ta) is only short-term.
The Effect of Niobium on the Mechanical and Thermodynamic Properties of Zirconium Alloys
Authors: Kong Xianggang , Kuang Huimin , Li An , Yu You , Kharchenko Dmitrii O. , Mao Jianjun , Wu Lu
Published: May 2024

The alloy element Nb plays an important role in improving the performance of zirconium alloys in nuclear reactors. The effect mechanism of Nb doping on mechanical and thermodynamic properties was investigated using experimental and theoretical methods. The results of this study showed us that Nb doping refines grains and enhances hardness. The hardness increases from 2.67 GPa of pure Zr to 2.99 GPa of Zr1.5Nb. Depending on the first-principles calculations, the hardness decreases with the increase in the Nb concentration in the Zr matrix, namely from 2.45 Gpa of pure Zr to 1.78 GPa of Zr1.5Nb. If the first-principles calculations indicate that the hardness decreases with the increase in the Nb concentration in the Zr matrix, grain refinement or defects could play a major role in the increase in hardness. Furthermore, regarding the effect of Nb doping on thermal expansion coefficients, the increase in Nb content causes the thermal expansion coefficients to decrease, which might stem from the strong binding energy between Nb and Zr atoms. The thermal conductivities of three samples show similar changing trends, indicating that thermal conductivity begins to decrease at room temperature and reaches a minimum value of around 400 °C. The thermal conductivity of pure zirconium samples is consistently higher, is more obvious than that of Nb-doped samples in the test range, and decreases with an increase in the doping concentration. The possible reasons for this might stem from the distortion of the Zr matrix due to Nb substitution doping and grain refinement, both of which cause phonon propagation scattering and thus hinder the propagation of phonons. The results obtained herein may be useful for the development of advanced nuclear fuels and waste forms that utilize zirconium in applications beyond their current usage.
The Influence of Hot Deformation on the Mechanical and Structural Properties of 42CrMo4 Steel
Authors: Pop Mariana , Sas-Boca Ioana-Monica , Frunză Dan , Popa Florin , Neag Adriana
Published: May 2024

The influence of elevated temperatures and strain rate on the mechanical and structural properties of steel 42CrMo4 were analysed experimentally in this paper. The experiments were based on uniaxial tension and compression tests at high temperatures between 700 °C and 1100 °C and strain rates in the range 0.0018–0.1 s−1. The influence of temperature and strain rate on yield stress, strain to fracture, hardness, structural changes, and fracture characteristics were analysed. The non-uniformity of deformations obtained at different values of the strain rate and temperature were also analysed. Analysis by scanning electron microscopy showed the ductile behaviour of the material. The degree of damage in the material caused by the presence of cavities increased with increasing deformation temperature. For all the presented deformation conditions, the formation of the fracture through the ductile fracture mechanism resulted from localized necking and the coalescence of microvoids. By increasing the deformation temperature and reducing the strain rate, the fracture behaviour of 42CrMo4 steel can be improved.
Comparative Analysis of Three Different Probe Designs for Reducing Hook Defects in FSW of AA6005-T6 Aluminum Alloy
Authors: Qin Liuyang , Zhang Hongxia , Bian Gongbo , Li Kewei , Dong Peng
Published: May 2024

Hook defects are common in FSW butt–lap joints, resulting in a significant safety hazard for the parts that suffer cyclic load. In this study, a numerical simulation based on the Euler–Lagrange coupling method was conducted to investigate the formation process of hook defect during FSW of AA6005-T6 aluminum alloy. The simulation results were validated with experimental data, showing good agreement. The formation of the hook defect is caused by the threads on the probe promoting material flow in the thickness direction. In order to further study the effect of probe morphology on hook defects, three kinds of probe models with different morphology were established and numerically simulated by the CEL method. The simulation results show that all three kinds of probes can reduce the size of the hook. The welds obtained using the left–left probe (LLP) and the three-plane probe (TPP) both exhibit void defects, while the welds obtained by a right–left probe (RLP) have no internal void defects. The experimental results show the same characteristics as the simulation results, and the size of the hook defect is reduced to 58 μm.
The Role of Lysophospholipid Metabolites LPC and LPA in the Pathogenesis of Chronic Obstructive Pulmonary Disease
Authors: Zhou Qiqiang , Chen Yahong , Liang Ying , Sun Yongchang
Published: May 2024

Chronic obstructive pulmonary disease (COPD) is a heterogeneous lung condition characterized by persistent respiratory symptoms and airflow limitation. While there are some available treatment options, the effectiveness of treatment varies depending on individual differences and the phenotypes of the disease. Therefore, exploring or identifying potential therapeutic targets for COPD is urgently needed. In recent years, there has been growing evidence showing that lysophospholipids, namely lysophosphatidylcholine (LPC) and lysophosphatidic acid (LPA), can play a significant role in the pathogenesis of COPD. Exploring the metabolism of lysophospholipids holds promise for understanding the underlying mechanism of COPD development and developing novel strategies for COPD treatment. This review primarily concentrates on the involvement and signaling pathways of LPC and LPA in the development and progression of COPD. Furthermore, we reviewed their associations with clinical manifestations, phenotypes, and prognosis within the COPD context and discussed the potential of the pivotal signaling molecules as viable therapeutic targets for COPD treatment.
Hydroclimate and Paleoenvironmental Variability from the Tonle Sap Lake Basin during the Angkor Period
Authors: Zhao Xinnan , Wang Jian , Zhao Wei , Cheng Hai
Published: May 2024

The profound impact of the Khmer Empire on Southeast Asia renders the Angkor Period particularly significant in guiding contemporary societies to advocate and promote policies that respond to climate change. We present a new continuous multi-proxy speleothem dataset from Tonle Sap Lake Basin, investigating hydroclimate variability and the paleoenvironment of Cambodia during the Angkor Period from the 9th to 15th centuries. In addition, two important climatic events on a decadal scale are clearly reconstructed. The first is the reduction of precipitation between 800 and 1000 AD and the relatively significant drought that the regional environment may have experienced from 950 to 1000 AD. The second is the anomalous wet period between 1000 and 1200 AD, during which the Southern Oscillation Index also reached its negative peak after a thousand years. The wet and dry conditions are highly consistent with the El Niño-dominated and northward Intertropical Convergence Zone.
Zircon U-Pb and Fission-Track Chronology of the Kaiyang Phosphate Deposit in the Yangtze Block: Implications for the Rodinia Supercontinent Splitting and Subsequent Thermal Events
Authors: Song Yina , Li Tianqi , Zhou Jiayi , Zhu Debin , Xiao Lingling
Published: May 2024

The Kaiyang phosphate mining area in Guizhou, which is located in the central–southern part of the Yangtze Block, hosts one of China’s more significant phosphate-enriched strata within the Doushantuo Formation. This formation is essential for phosphate mining and also preserves multiple magmatic events, which are closely linked to the assembly and breakup of the Rodinia supercontinent. Our comprehensive studies in petrology, geochemistry, zircon U-Pb geochronology, and fission-track dating reveal that the primary ore mineral in phosphorite is collophane, which is accompanied by dolomite, quartz, pyrite, and zircon. The majority of detrital zircons in the phosphorite, as well as the overlying dolostone and underlying sandstone, are of magmatic origin, with a record of multiple stages of magmatic ages. Among these, the older age groups of ~2500 Ma and ~2000–1800 Ma represent the ancient crystalline basement of the Yangtze Block from the Paleoproterozoic era. The three main age peaks at ~880 Ma, ~820 Ma, and ~780 Ma indicate that the magmatic event at ~880 Ma was related to the assembly of the Rodinia supercontinent during the Grenvillian period. The most prominent age peak at ~820 Ma marks a critical time point for the transition from assembly to the breakup of the Rodinia supercontinent, with the Yangtze Block’s response to the supercontinent breakup events lasting at least until ~780 Ma. The youngest group of zircon ages from the phosphorite (~594 Ma), and the underlying sandstone (~529 Ma) establishes the minimum age for the phosphorite formation, indicating that the Doushantuo phosphorite layer in the Kaiyang area was formed after 594 Ma, i.e., even later than 529 Ma. The zircon fission-track ages in the three rock types of the phosphorite-bearing rocks can be divided into three groups: 501–489 Ma, ~366 Ma, and 53–39 Ma. All of these groups are presumed to be associated with the tectonic uplift events that follow mineralization. The first two age groups correspond to the two major tectonic uplift events during the Caledonian period, which resulted in the formation of the Qianzhong Uplift. The ages of 53–39 Ma are related to the late uplift of the Himalayan orogeny, and they represent its response in the Kaiyang area of Guizhou.
Exploring the Composition of Egyptian Faience
Authors: Falcone Francesca , Aquilino Maria , Stoppa Francesco
Published: May 2024

Egyptian Faience, a revolutionary innovation in ancient ceramics, was used for crafting various objects, including amulets, vessels, ornaments, and funerary figurines, like shabtis. Despite extensive research, many aspects of ancient shabti production technology, chemistry and mineralogy remain relatively understudied from the 21st to the 22nd Dynasty, belonging to a recovered 19th-century private collection. The fragments’ origin is tentatively identified in the middle Nile valley in the Luxor area. Our study focused on a modest yet compositionally interesting small collection of shabti fragments to provide information on the glaze’s components and shabti’s core. We found that the core is a quartz and K-feldspars silt blended with an organic component made of plastic resins and vegetable fibres soaked with natron. The studied shabti figurines, after being modelled, dried, and covered with coloured glaze, were subjected to a firing process. Sodium metasilicate and sulphate compounds formed upon contact of the glaze with the silica matrix, forming a shell that holds together the fragile inner matrix. The pigments dissolved in the sodic glaze glass, produced by quartz, K-feldspars, and natron frit, are mainly manganese (Mn) and copper (Cu) compounds. The ratio Cu2O/CaO > 5 produces a blue colour; if <5, the glaze is green. In some cases, Mg and As may have been added to produce a darker brown and an intense blue, respectively. Reaction minerals provided information on the high-temperature firing process that rapidly vitrified the glaze. These data index minerals for the firing temperature of a sodic glaze, reaching up to a maximum of 1050 °C.
Photocatalytic Degradation of Naproxen: Intermediates and Total Reaction Mechanism
Authors: González-Pereyra Daniela , Acosta Ilse , Zermeño Brenda , Aguilar Johana , Leyva Elisa , Moctezuma Edgar
Published: May 2024

Photochemical and photocatalytic oxidation of naproxen (NPX) with UV-A light and commercial TiO2 under constant flow of oxygen have been investigated. Adsorption experiments indicated that 90% of the solute remained in the solution. Combined chemical analysis of samples on the photochemical degradation indicated that NPX in an aqueous solution (20 ppm) is efficiently transformed into other species but only 18% of the reactant is mineralized into CO2 and water after three hours of reaction. Performing the photocatalytic oxidation in the presence of TiO2, more than 80% of the organic compounds are mineralized by reactive oxidation species (ROS) within four hours of reaction. Analysis of reaction mixtures by a combination of analytical techniques indicated that naproxen is transformed into several aromatic naphthalene derivatives. These latter compounds are eventually transformed into polyhydroxylated aromatic compounds that are strongly adsorbed onto the TiO2 surface and are quickly oxidized into low-molecular-weight acids by an electron transfer mechanism. Based on this and previous studies on NPX photocatalytic oxidation, a unified and complete degradation mechanism is presented.
Imidazole Carbamates as a Promising Alternative for Treating Trichomoniasis: In Vitro Effects on the Growth and Gene Expression of Trichomonas vaginalis
Authors: Martínez-Rosas Víctor , Navarrete-Vázquez Gabriel , Ortega-Cuellar Daniel , Arreguin-Espinosa Roberto , Pérez de la Cruz Verónica , Calderón-Jaimes Ernesto , Enríquez-Flores Sergio , Wong-Baeza Carlos , Baeza-Ramírez Isabel , Morales-Luna Laura , Vázquez-Bautista Montserrat , Rojas-Alarcón Miriam Abigail , Hernández-Ochoa Beatriz , Gómez-Manzo Saúl
Published: May 2024

Metronidazole (MTZ) is the most common drug used against Trichomonas vaginalis (T. vaginalis) infections; however, treatment failures and high rates of recurrence of trichomoniasis have been reported, suggesting the presence of resistance in T. vaginalis to MTZ. Therefore, research into new therapeutic options against T. vaginalis infections has become increasingly urgent. This study investigated the trichomonacidal activity of a series of five imidazole carbamate compounds (AGR-1, AGR-2, AGR-3, AGR-4, and AGR-5) through in vitro susceptibility assays to determine the IC50 value of each compound. All five compounds demonstrated potent trichomonacidal activity, with IC50 values in the nanomolar range and AGR-2 being the most potent (IC50 400 nM). To gain insight into molecular events related to AGR-induced cell death in T. vaginalis, we analyzed the expression profiles of some metabolic genes in the trophozoites exposed to AGR compounds and MTZ. It was found that both AGR and MTZ compounds reduced the expression of the glycolytic genes (CK, PFK, TPI, and ENOL) and genes involved in metabolism (G6PD, TKT, TALDO, NADHOX, ACT, and TUB), suggesting that disturbing these key metabolic genes alters the survival of the T. vaginalis parasite and that they probably share a similar mechanism of action. Additionally, the compounds showed low cytotoxicity in the Caco-2 and HT29 cell lines, and the results of the ADMET analysis indicated that these compounds have pharmacokinetic properties similar to those of MTZ. The findings offer significant insights that can serve as a basis for future in vivo studies of the compounds as a potential new treatment against T. vaginalis.
An Integrated Strategy Based on 10-DAB Extraction and In Situ Whole-Cell Biotransformation of Renewable Taxus Needles to Produce Baccatin III
Authors: Kou Ping , Yu Yingying , Wang He , Zhang Yuchi , Jin Zhaoxia , Yu Fang
Published: May 2024

Baccatin III is a crucial precursor in the biosynthesis pathway of paclitaxel. Its main sources are extraction from Taxus or chemical synthesis using 10-deacetylbaccatin III (10-DAB) as substrate. However, these preparation approaches exhibit serious limitations, including the low content of baccatin III in Taxus and the complicated steps of chemical synthesis. Heterologous expression of 10-deacetylbaccatin III-10-O-acetyltransferase (TcDBAT) in microbial strains for biotransformation of 10-DAB is a promising alternative strategy for baccatin III production. Here, the promotion effects of glycerol supply and slightly acidic conditions with a low-temperature on the catalysis of recombinant TcDBAT strain were clarified using 10-DAB as substrate. Taxus needles is renewable and the content of 10-DAB is relatively high, it can be used as an effective source of the catalytic substrate 10-DAB. Baccatin III was synthesized by integrating the extraction of 10-DAB from renewable Taxus needles and in situ whole-cell catalysis in this study. 40 g/L needles were converted into 20.66 mg/L baccatin III by optimizing and establishing a whole-cell catalytic bioprocess. The method used in this study can shorten the production process of Taxus extraction for baccatin III synthesis and provide a reliable strategy for the efficient production of baccatin III by recombinant strains and the improvement of resource utilization rate of Taxus needles.
Changes in the Physicochemical and Bioactive Properties of Yerba Mate Depending on the Brewing Conditions
Authors: Najman Katarzyna , Rajewski Rafał , Sadowska Anna , Hallmann Ewelina , Buczak Krzysztof
Published: May 2024

Yerba Mate drink made from dried and crushed leaves and twigs of Paraguayan holly (Ilex paraguariensis A. St.-Hil.), which is a valuable source of bioactive substances, in particular antioxidants. The available literature lacks data on changes in the content and profile of bioactive compounds such as tannins, caffeine, the phenolic acid profile of flavonoids and carotenoids, as well as total polyphenol content and antioxidant activity in Yerba Mate infusions depending on different brewing conditions, and how different brewing conditions affect the physicochemical properties of these infusions. Therefore, this study evaluated the physicochemical properties of dried and Yerba Mate infusions prepared via single and double brewing processes at 70 °C and 100 °C. The organoleptic evaluation, as well as the instrumental color measurement, showed significant changes in the total color difference (ΔE) and the L*a*b* chromatic coordinates of dried Yerba Mate samples and their infusions. Moreover, the research showed higher contents of tannins (mean 1.36 ± 0.14 g/100 g d.m.), caffeine (mean 17.79 ± 3.49 mg/g d.m.), carotenoids (mean 12.90 ± 0.44 μg/g d.m.), phenolic acids (mean 69.97 ± 7.10 mg/g d.m.), flavonoids (mean 5.47 ± 1.78 mg/g d.m.), total polyphenols (mean 55.26 ± 8.51 mg GAE/g d.m.), and antioxidant activity (mean 2031.98 ± 146.47 μM TEAC/g d.m.) in single-brewed Yerba Mate infusions compared to double-brewed (0.77 ± 0.12 g/100 g d.m., 14.28 ± 5.80 mg/g d.m., 12.67 ± 0.62 μg/g d.m., 57.75 ± 8.73 mg/g d.m., 3.64 ± 0.76 mg/g d.m., 33.44 ± 6.48 mg GAE/g d.m. and 1683.09 ± 155.34 μM TEAC/g d.m., respectively). In addition, infusions prepared at a lower temperature (70 °C) were characterized by a higher content of total polyphenols and higher antioxidant activity, in contrast to the tannin and carotenoid contents, the levels of which were higher at 100 °C than at 70 °C. Considering the high amount of bioactive ingredients, in particular antioxidants, and a wide range of health benefits, it is worth including Yerba Mate in the daily diet.
Bioactive Peptide Profiling in Collagen Hydrolysates: Comparative Analysis Using Targeted and Untargeted Liquid Chromatography–Tandem Mass Spectrometry Quantification
Authors: Oztug Merve
Published: May 2024

The investigation of collagen hydrolysates (CHs) is essential due to their widespread use in health, cosmetic, and therapeutic industries, attributing to the presence of bioactive dipeptides (DPs) and tripeptides (TPs). This study developed a novel targeted liquid chromatography–tandem mass spectrometry (LC-MS/MS) method with propyl chloroformate (PCF) derivatization to measure three bioactive peptides—Hydroxyprolyl-glycine (Hyp-Gly), Glycyl-prolyl-hydroxyproline (Gly-Pro-Hyp), and Prolyl-hydroxyproline (Pro-Hyp)—in CHs, with strong correlation coefficients (0.992, 1.000, and 0.995, respectively) and low limits of detection (LODs) of 1.40, 0.14, and 1.16 µM, respectively. Untargeted data-dependent acquisition (DDA) analyses measured peptide size distribution, while amino acid analysis assessed nutritional content. The analysis of ten commercial CHs revealed similar amino acid profiles but varied peptide lengths, indicating diverse hydrolysis conditions. Products with higher proportions of smaller peptides showed elevated levels of the targeted bioactive peptides, suggesting that a smaller peptide size may increase bioactivity. These findings can inform the optimization of CH supplements, providing consumers with detailed peptide content for more informed choices. Data are available via ProteomeXchange with the identifier PXD051699.
Prognostic Value of New Sarcopenia Screening Tool in the Elderly—SARC-GLOBAL
Authors: Vicedomini Ana Carolina Costa , Waitzberg Dan L. , Lopes Natalia Correia , Magalhães Natalia , Prudêncio Ana Paula A. , Jacob Filho Wilson , Busse Alexandre Leopold , Ferdinando Douglas , Alves Tatiana Pereira , Pereira Rosa Maria Rodrigues , Belarmino Giliane
Published: May 2024

Sarcopenia screening tools have a low capacity to predict adverse outcomes that are consequences of sarcopenia in the elderly population. This study aimed to evaluate the ability of a new sarcopenia screening tool SARC-GLOBAL to predict negative clinical outcomes in the elderly. A total of 395 individuals were evaluated in a 42-month period. The screening tools SARC-GLOBAL, SARC-F, and SARC-CalF and the diagnosis of sarcopenia according to European Working Group on Sarcopenia in Older Persons (EWGSOP2) were performed at the beginning of the study. Logistic and Poisson regression models were applied to assess the predictive value of the tools for the odds and risks of negative clinical outcomes, respectively. The most common negative clinical outcome in the followed population was falls (12.9%), followed by infections (12.4%), hospitalizations (11.8%), fractures (4.3%), and deaths (2.7%). Both SARC-GLOBAL and SARC-F were similar in predicting the odds of falls and hospitalizations during the follow up period, however SARC-CalF only predicted the odds of hospitalizations at 42 months.
Nutritional Strategies for Preterm Neonates and Preterm Neonates Undergoing Surgery: New Insights for Practice and Wrong Beliefs to Uproot
Authors: De Rose Domenico Umberto , Lapillonne Alexandre , Iacobelli Silvia , Capolupo Irma , Dotta Andrea , Salvatori Guglielmo
Published: May 2024

The nutrition of preterm infants remains contaminated by wrong beliefs that reflect inexactitudes and perpetuate old practices. In this narrative review, we report current evidence in preterm neonates and in preterm neonates undergoing surgery. Convictions that necrotizing enterocolitis is reduced by the delay in introducing enteral feeding, a slow advancement in enteral feeds, and the systematic control of residual gastric volumes, should be abandoned. On the contrary, these practices prolong the time to reach full enteral feeding. The length of parenteral nutrition should be as short as possible to reduce the infectious risk. Intrauterine growth restriction, hemodynamic and respiratory instability, and patent ductus arteriosus should be considered in advancing enteral feeds, but they must not translate into prolonged fasting, which can be equally dangerous. Clinicians should also keep in mind the risk of refeeding syndrome in case of high amino acid intake and inadequate electrolyte supply, closely monitoring them. Conversely, when preterm infants undergo surgery, nutritional strategies are still based on retrospective studies and opinions rather than on randomized controlled trials. Finally, this review also highlights how the use of adequately fortified human milk is strongly recommended, as it offers unique benefits for immune and gastrointestinal health and neurodevelopmental outcomes.
Changes in Fecal Short-Chain Fatty Acids in IBS Patients and Effects of Different Interventions: A Systematic Review and Meta-Analysis
Authors: Ju Xuan , Jiang Zhenliang , Ma Jiayin , Yang Dong
Published: May 2024

Context: Short-chain fatty acids (SCFAs) have been reported to be associated with the pathogenesis of irritable bowel syndrome (IBS), but the results are conflicting. Objective: Here, a systematic review of case–control studies detecting fecal SCFAs in IBS patients compared with healthy controls (HCs) and self-controlled studies or randomized controlled trials (RCTs) investigating fecal SCFA alterations after interventions were identified from several databases. Data sources: A systematic search of databases (PubMed, Web of Science, and Embase) identified 21 studies published before 24 February 2023. Data extractions: Three independent reviewers completed the relevant data extraction. Data analysis: It was found that the fecal propionate concentration in IBS patients was significantly higher than that in HCs, while the acetate proportion was significantly lower. Low-FODMAP diets significantly reduced the fecal propionate concentration in the IBS patients while fecal microbiota transplantation and probiotic administration did not significantly change the fecal propionate concentration or acetate proportion. Conclusions: The results suggested that the fecal propionate concentration and acetate proportion could be used as biomarkers for IBS diagnosis. A low-FODMAP diet intervention could potentially serve as a treatment for IBS while FMT and probiotic administration need more robust trials.
A Comprehensive Study on Elasticity and Viscosity in Biomechanics and Optical Properties of the Living Human Cornea
Authors: Ávila Francisco J. , del Barco Óscar , Marcellán María Concepción , Remón Laura
Published: May 2024

Corneal biomechanics is a hot topic in ophthalmology. The biomechanical properties (BMPs) of the cornea have important implications in the management and diagnosis of corneal diseases such as ectasia and keratoconus. In addition, the characterization of BMPs is crucial to model the predictability of a corneal surgery intervention, the outcomes of refractive surgery or the follow-up of corneal diseases. The biomechanical behavior of the cornea is governed by viscoelastic properties that allow, among other structural implications, the damping of excess intraocular pressure and the reduction of damage to the optic nerve. Currently, the most versatile and complete methods to measure corneal viscoelasticity are based on air-puff corneal applanation. However, these methods lack the ability to directly measure corneal viscosity. The aim of this work is to propose a new methodology based on the analysis of corneal air-puff measurements through the standard linear solid model (SLSM) to provide analytical expressions to separately calculate the elastic and time-dependent (corneal retardation time and viscosity) properties. The results show the mean values of elasticity (E), viscosity (Ƞ) and corneal retardation time (τ) in a sample of 200 young and healthy subjects. The influence of elasticity and viscosity on viscoelasticity, high-order corneal aberrations and optical transparency is investigated. Finally, the SLSM fed back from experimental E and Ƞ values is employed to compare the creep relaxation response between a normal, an ocular hypertension patient and an Ortho-K user. Corneal biomechanics is strongly affected by intraocular pressure (IOP); however, corneal hysteresis (CH) analysis is not enough to be employed as a risk factor of glaucoma progression. Low values of CH can be accompanied by high or low corneal elasticity and viscosity depending on the IOP threshold from which the time-dependent biomechanical properties trends are reversed.
Adhesion Properties and Stability of Polar Polymers Treated by Air Atmospheric Pressure Plasma
Authors: Ciobanu Roxana , Mihăilă Ilarion , Borcia Cătălin , Borcia Gabriela
Published: May 2024

This study continues the discussion on the surface modification of polymers using an atmospheric pressure plasma (APP) reactor in air. These results complement prior research focusing on nonpolar polymers. Polymers, such as polyethylene terephthalate, polyetheretherketone, and polymethyl methacrylate, containing structurally bonded oxygen are studied, representing a range of properties such as oxygen content, crystalline/amorphous structure, polarity, functionality, and aliphatic/aromatic structure. APP induces superior wetting properties on the hydrophilic polymer surfaces with rapid and uniform modification within 0.5 s of exposure. The amorphous structures undergo additional modification for longer exposure. Moreover, the aliphatic chain structures require longer plasma exposure to reach surface modification equilibrium. The polar polymers reach a limit level of modification corresponding to a minimum water contact angle of about 50°. The surface polarity increases on average by a factor of approximately two. The equilibrium values of the adhesion work attained after post-processing recovery fall within a limited range of about 100–120 mJ/m2. The enhancement of surface functionality through the creation of oxidized groups primarily depends on the initial oxygen content and reaches a limit of about 40 at.% oxygen. The surface properties of the treated polar surfaces exhibit good stability, comparable to that of the previously tested nonpolar polymers.
Improving Hemocompatibility of Polysulfone Membrane by UV-Assisted Grafting of Sulfonated Chitosan
Authors: Yan Sheng , Qiu Yunren
Published: May 2024

The most prevalent type of hemodialysis membrane is polysulfone (PSf). However, due to inadequate biocompatibility, it significantly compromises the safety of dialysis for patients. In this study, we modify the surface of the PSf membrane with 2,4-dihydroxybenzophenone (DBPh) groups to serve as anchoring sites during UV irradiation. Subsequently, a tailored sulfonated dihydroxy propyl chitosan (SDHPCS) is grafted onto the modified PSf membrane to compensate for the deficiencies in hydrophilic additives. The modified PSf membrane exhibits outstanding hydrophilicity and stability, as demonstrated by its characterization and evaluation. This paper focuses on investigating the interaction between platelet membrane formation, protein adsorption, and anticoagulant activity. The results show that the modified PSf membrane exhibits remarkable enhancement in surface hydrophilicity, leading to a significant reduction in protein and platelet adsorption as well as adhesion.
Stable 3D Deep Convolutional Autoencoder Method for Ultrasonic Testing of Defects in Polymer Composites
Authors: Liu Yi , Yu Qing , Liu Kaixin , Zhu Ningtao , Yao Yuan
Published: May 2024

Ultrasonic testing is widely used for defect detection in polymer composites owing to advantages such as fast processing speed, simple operation, high reliability, and real-time monitoring. However, defect information in ultrasound images is not easily detectable because of the influence of ultrasound echoes and noise. In this study, a stable three-dimensional deep convolutional autoencoder (3D-DCA) was developed to identify defects in polymer composites. Through 3D convolutional operations, it can synchronously learn the spatiotemporal properties of the data volume. Subsequently, the depth receptive field (RF) of the hidden layer in the autoencoder maps the defect information to the original depth location, thereby mitigating the effects of the defect surface and bottom echoes. In addition, a dual-layer encoder was designed to improve the hidden layer visualization results. Consequently, the size, shape, and depth of the defects can be accurately determined. The feasibility of the method was demonstrated through its application to defect detection in carbon-fiber-reinforced polymers.
Electromagnetic Interference Shielding Properties of Highly Flexible Poly(styrene-co-butyl acrylate)/PEDOT:PSS Films Fabricated by Latex Technology
Authors: Lee Seung Chang , Bang Yong Bin , Park Hyun Ho , Na Hyo Yeol , Lee Seong Jae
Published: May 2024

As the use of stretchable electronic devices increases, the importance of flexible electromagnetic interference (EMI) shielding films is emerging. In this study, a highly flexible shielding film was fabricated using poly(styrene-co-butyl acrylate) (p(St-co-BA)) latex as a matrix and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as a conductive filler, and then the mechanical properties and EMI shielding performance of the film were examined. Styrene and butyl acrylate were copolymerized to lower the high glass transition temperature and increase the ductility of brittle polystyrene. The latex blending technique was used to produce a shielding film in which the aqueous filler dispersion was uniformly dispersed in the emulsion polymerized resin. To determine the phase change in the copolymer matrix with temperature, the storage modulus was measured, and a time–temperature superposition master curve was constructed. The drying temperature of water-based copolymer resin suitable for film fabrication was set based on this curve. The glass transition temperature and flexibility of the blends were determined by evaluating the thermomechanical analysis and tensile tests. The EMI shielding effectiveness (SE) of the films was analyzed at frequencies from 50 MHz to 1.5 GHz, covering the VHF and UHF ranges. As the filler content increased, the SE of the blend film increased, but the elongation increased until a certain content and then decreased. The optimal content of PEDOT:PSS that satisfied both the ductility and shielding performance of the film was found to be 10 wt%. In this case, the elongation at break reached 300%, and the SE of a 1.6 mm thick film was about 35 dB. The film developed in this study can be used as an EMI shielding material that requires high flexibility.
Masked Image Modeling Auxiliary Pseudo-Label Propagation with a Clustering Central Rectification Strategy for Cross-Scene Classification
Authors: Zhang Xinyi , Zhuang Yin , Zhang Tong , Li Can , Chen He
Published: May 2024

Cross-scene classification focuses on setting up an effective domain adaptation (DA) way to transfer the learnable knowledge from source to target domain, which can be reasonably achieved through the pseudo-label propagation procedure. However, it is hard to bridge the objective existing severe domain discrepancy between source and target domains, and thus, there are several unreliable pseudo-labels generated in target domain and involved into pseudo-label propagation procedure, which would lead to unreliable error accumulation to deteriorate the performance of cross-scene classification. Therefore, in this paper, a novel Masked Image Modeling Auxiliary Pseudo-Label Propagation called MIM-AP2 with clustering central rectification strategy is proposed to improve the quality of pseudo-label propagation for cross-scene classification. First, in order to gracefully bridge the domain discrepancy and improve DA representation ability in-domain, a supervised class-token contrastive learning is designed to find the more consistent contextual clues to achieve knowledge transfer learning from source to target domain. At the same time, it is also incorporated with a self-supervised MIM mechanism according to a low random masking ratio to capture domain-specific information for improving the discriminability in-domain, which can lay a solid foundation for high-quality pseudo-label generation. Second, aiming to alleviate the impact of unreliable error accumulation, a clustering central rectification strategy is designed to adaptively update robustness clustering central representations to assist in rectifying unreliable pseudo-labels and learning a superior target domain specific classifier for cross-scene classification. Finally, extensive experiments are conducted on six cross-scene classification benchmarks, and the results are superior to other DA methods. The average accuracy reached 95.79%, which represents a 21.87% improvement over the baseline. This demonstrates that the proposed MIM-AP2 can provide significantly improved performance.
An Attention-Guided Complex-Valued Transformer for Intra-Pulse Retransmission Interference Suppression
Authors: Wang Yifan , Li Yibing , Zhou Zitao , Yu Gang , Li Yingsong
Published: May 2024

With the maturation of digital radio frequency memory (DRFM) technology, various intra-pulse retransmission interference methods have emerged. These flexible and changeable retransmission interference methods pose significant challenges to radar detection tasks, particularly in modern battlefields. This paper proposes an attention-guided complex-valued transformer (AGCT) as a solution. First, the encoder maps the received signal contaminated by interference and noise into a high-dimensional space. Then, the dilated convolution block (DCB) group and attention block (AB) group in the mask estimator extract the delicate multi-scale features and large-scale features of the interference, respectively, to obtain a multidimensional space mask. Finally, the decoder restores interference to the time domain and outputs the estimated target echo using residual learning. Considering the characteristics of intra-pulse interference, we introduced the energy attention block (EAB) at the end of the DCBs and the ABs within our network. This addition ensures a heightened focus on extracting interference features. Furthermore, we implemented a curriculum learning strategy during the network training. This approach gradually acclimates the network to fit different types of retransmission interference, starting from simpler to more complex scenarios. Our extensive experiments, conducted under various conditions, have provided compelling evidence of the AGCT’s superior performance. Compared to the comparative network, the AGCT’s advantages are particularly pronounced under more harsh conditions, demonstrating its robustness and effectiveness.
An Improved Approach to Estimate Stocking Rate and Carrying Capacity Based on Remotely Sensed Phenology Timings
Authors: Shi Yan , Brierley Gary , Perry George L. W. , Gao Jay , Li Xilai , Prishchepov Alexander V. , Li Jiexia , Han Meiqin
Published: May 2024

Accurate estimation of livestock carrying capacity (LCC) and implementation of an appropriate actual stocking rate (ASR) are key to the sustainable management of grazing adapted alpine grassland ecosystems. The reliable determination of aboveground biomass is fundamental to these determinations. Peak aboveground biomass (AGBP) captured from satellite data at the peak of the growing season (POS) is widely used as a proxy for annual aboveground biomass (AGBA) to estimate LCC of grasslands. Here, we demonstrate the limitations of this approach and highlight the ability of POS in the estimation of ASR. We develop and trail new approaches that incorporate remote sensing phenology timings of grassland response to grazing activity, considering relations between biomass growth and consumption dynamics, in an effort to support more accurate and reliable estimation of LCC and ASR. The results show that based on averaged values from large-scale studies of alpine grassland on the Qinghai-Tibet Plateau (QTP), differences between AGBP and AGBA underestimate LCC by about 31%. The findings from a smaller-scale study that incorporate phenology timings into the estimation of annual aboveground biomass reveal that summer pastures in Haibei alpine meadows were overgrazed by 11.5% during the study period from 2000 to 2005. The methods proposed can be extended to map grassland grazing pressure by predicting the LCC and tracking the ASR, thereby improving sustainable resource use in alpine grasslands.
Digital Transformation of Hungary’s Economy between 2015 and 2021: Results and Future Objectives
Authors: Török László
Published: May 2024

Hungary is a member of the European Union (E.U.), so more than three-quarters of its trade relations are with the E.U. Hungary’s strategic objective is to be among the top-ten E.U. member states in digitalization by 2030. This study aims to examine the country’s digitization development and planned digitization programs and, based on these, to predict Hungary’s expected digitization status. This study also attempts to answer whether Hungary is among the ten most digitally developed E.U. member states. We use the K-means clustering method to assess the current state of digitization and different generic methods to determine future development. The results show that Hungary’s digital development is close to the middle level of the E.U. However, future digital development in Hungary will be more dynamic than in the European Union. This more dynamic Hungarian growth is predicted to catch up with the average of the E.U.’s digital development. However, the results of the extrapolation calculations show that the Hungarian goal of Hungary being among the ten most developed digital countries in the E.U. by 2030 is unrealistic.
Utilizing the Taguchi Method to Optimize Rotor Blade Geometry for Improved Power Output in Ducted Micro Horizontal-Axis Wind Turbines
Authors: Ouyang Kwan , Chen Tzeng-Yuan , You Jun-Jie
Published: May 2024

This numerical study utilized the Taguchi method to systematically optimize the blade geometry of a ducted micro horizontal-axis wind turbine (HAWT) for moving vehicles to enhance the output power coefficient. Three geometric parameters of the rotor, namely, the number of blades, rotor solidity, and blade pitch angle, were investigated. The optimum parameter design includes eight blades, rotor solidity of 60%, and a pitch angle of 30°, where the blade pitch angle had the most significant effect on the rotor performance. This result confirms that high rotor solidity is more suitable for micro HAWT. The CP,max value achieved with the optimum geometry was 0.432, which was 39.4% higher than that achieved with the worst blade geometry. The aerodynamic characteristics of this wind turbine were also investigated. Compared with the worst blade geometry, the rotor with the optimum blade geometry drew more airflow into the duct and exhibited a higher CP,max due to a greater pressure difference between the windward and leeward sides of the blades. The optimum blade geometry achieved a CT,max of 0.43, which was 38.7% higher than the worst blade geometry. The investigated untwisted blades exhibited low torque near their tips; therefore, the use of twisted blades is recommended for further increasing the torque generated at the blade tip and thus the turbine’s output power. This study facilitates insight into blade geometry effects on rotor performance and helps improve wind energy efficiency, contributing to sustainable development goals (SDGs) like SDG 7 (affordable and clean energy).
Improved Machine Learning Model for Urban Tunnel Settlement Prediction Using Sparse Data
Authors: Yu Gang , Jin Yucong , Hu Min , Li Zhisheng , Cai Rongbin , Zeng Ruochen , Sugumaran Vijiayan
Published: May 2024

Prediction tunnel settlement in shield tunnels during the operation period has gained increasing significance within the realm of maintenance strategy formulation. The sparse settlement data during this period present a formidable challenge for predictive Artificial Intelligence (AI) models, as they may not handle non-stationary relationships effectively or have the risk of overfitting. In this study, we propose an improved machine learning (ML) model based on sparse settlement data. We enhance training data via time series clustering, use time decomposition to uncover latent features, and employ Extreme Gradient Boosting (XGBoost) v1.5.1 with Bayesian Optimization (BO) v1.2.0 for precise predictions. Comparative experiments conducted on different acquisition points substantiate our model’s efficacy, the in-training set yielding a Mean Absolute Error (MAE) of 0.649 mm, Root Mean Square Error (RMSE) of 0.873 mm, Mean Absolute Percentage Error (MAPE) of 3.566, and Coefficient of Determination (R2) of 0.872, and the in-testing set yielding a MAE of 0.717 mm, RMSE of 1.048 mm, MAPE of 4.080, and R2 of 0.846. The empirical results show the superiority of the proposed model compared to simple ML models and a complex neural network model, as it has a lower prediction error and higher accuracy across different sparse settlement datasets. Moreover, this paper underlines that accurate settlement predictions contribute to achieving some Sustainable Development Goals (SDGs). Specifically, preventive tunnel maintenance strategies based on predictive results can enhance tunnels’ long-term operational reliability, which is in accordance with SDG 9 (Industry, Innovation, and Infrastructure) and SDG 11 (Sustainable Cities and Communities).