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Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(english edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-TALOOKOLAeI H.GHANDVAR e.JUMAeV s.KHATIR T.CUONG-Le school of Mechanical engineering Babol Noshirvani University of Technology Department of Mechanical engineering Faculty of Engineering New Uzbekistan University University of Business and science Center for engineering Application and Technology solutions Ho Chi Minh City Open University

This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. The strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. The curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. subsequently, the natural frequencies and transient response of the system are determined. The accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANsYs, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

关键词： double curved beam finite element method functionally graded porous (FGP) material intermediate straight beam O313 vibration analysis

Predictive value of the systemic immune inflammation index in recurrence of atrial fibrillation after radiofrequency catheter ablation

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World Journal of Cardiology 2025年第1期17卷 22-27页

作者： Alexander e Berezin Department of Internal Medicine-II Paracelsus Medical University SalzburgSalzburg 5020Austria

The recurrence of atrial fibrillation(AF)in patients after successful radiofrequency catheter ablation(RFCA)appears to be an unresolved clinical issue and needs to be clearly *** are many factors associated with AF recurrence,such as duration of AF,male sex,concomitant heart failure,hemodynamic parameters,chronic obstructive pulmonary disease,hypertension,obstructive sleep apnea,hyperthyroidism,smoking and ***,the inflammatory changes are strongly associated with electrical and structural cardiac remodeling,cardiac damage,myocardial fibrotic changes,microvascular dysfunction and altered reparative *** this context,biomarkers reflecting the different stages of AF pathogenesis deserve thorough *** authors of the retrospective study revealed that one-year recurrence rate of non-valvular AF in the high systemic immune inflammation(sII)index group was significantly increased compared to that of the low sII index group and provided additional predictive value to the ***,the authors suggest that this biomarker may help physicians to optimize the selection of AF patients and to develop a personalized treatment *** conclusion,the sII index may serve as a valuable indicator of recurrent AF in patients after RFCA and may be a biomarker with plausible predictive value for poor clinical outcomes.

关键词： systemic immune inflammation index Recurrent atrial fibrillation Radiofrequency catheter ablation Biomarkers APPLe score Prediction

Merging bound states in the continuum in an open acoustic resonator

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science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 120-127页

作者： Lujun Huang Bin Jia Artem s.Pilipchuk sibo Huang Chen shen Almas F.sadreev Yong Li Andrey e.Miroshnichenko school of Physics and electronic sciences East China Normal UniversityShanghai 200241China Institute of acoustics Tongji UniversityShanghai 200092China L.V.Kirensky Institute of Physics Krasnoyarsk 660036Russia Department of Mechanical engineering Rowan UniversityGlassboro 08028USA school of engineering and Technology University of New South Wales at CanberraACT 2610Australia

Bound states in the continuum(BICs)are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional toΔL^(−4),whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective non-Hermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

Protective activity of adipose-derived stem cell extracellular vesicles in ischemia and/or reperfusion

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World Journal of stem Cells 2025年第1期17卷 1-5页

作者： Alexander e Berezin Internal Medicine-II Paracelsus Medical University SalzburgSalzburg 5020Austria

Increasing evidence of the significant clinical value of protection against ischemia/reperfusion injury has contributed to the realization of the independent importance of this approach in improving prognosis and reducing cardiovascular *** vesicles(eVs)derived by adipose mesenchymal stem cells may mediate the paracrine effects of stem cells and provide regenerative and anti-inflammatory properties,which are enhanced byγ-aminobutyric *** protective effects on cardiac myocytes may result from the eV embarked by miR-21-5p,which is a target for thioredoxin-interacting protein,regulating the formation of thioredoxin-interacting protein-thioredoxin complexes and subsequently enhancing the antioxidant activity of *** has been found thatγ-aminobutyric acid governs myocardial bioenergetics through suppressing inflammation and supporting mitochondrial ***,stem cell-based cell-free therapy based on adipose-derived stem cell eVs is considered a promising approach to individualized management of ischemia-induced cardiomyopathy.

关键词： extracellular vesicles Adipose mesenchymal stem cells MicroRNA-21-5p Cardiac protection Ischemia Reperfusion

Green synthesis of glycolic acid through the electrocatalytic reduction of oxalic acid over black TiO_(2): An experimental and theoretical study

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Journal of energy Chemistry 2025年第1期100卷 544-556页

作者： Hugo Olvera-Vargas Oscar Andrés Jaramillo-Quintero Luis Darío Alarcón León Orlando Castro-Ocampo Christian A.Celaya Marina e.Rincón Jesús Muñiz Instituto de energías Renovables Universidad Nacional Autónoma de México(IER-UNAM)Priv.Xochicalco s/nCol.CentroTemixcoMorelos.CP 62580Mexico Centro de Nanociencias y Nanotecnología Universidad Nacional Autónoma de México(UNAM)Km 107Carretera Tijuana-EnsenadaEnsenadaB.C.C.P.22800Mexico

Herein,we present the electrocatalytic four-electron hydrogenation of oxalic acid into glycolic acid using black TiO_(2)as an *** acid is an abundant compound found in several sources of organic *** results showed a high selectivity of black TiO_(2)toward glycolic acid,with the formation of glyoxylic acid being the rate-limiting step (glyoxylic acid is the two-electron intermediate).The highest Faradaic efficiency (Fe) of 69.6%±8.3% was achieved at 10.2 mA cm^(-2)in 4 h of electrolysis using an H-type cell operated at room temperature,with 50.2%±3.8% of oxalic acid conversion (degradation kinetic constant k=0.0042±0.0001 min-1),58.8%±7.0%of reaction yield and 1.2±0.18 g L-1of glycolic acid production.A theoretical model of black TiO_(2)coming from anatase TiO_(2)was implemented by introducing Ti3+defects,which gave black TiO_(2)the theoretical capability to easily transform oxalic acid into glycolic acid as experimentally *** reaction mechanism was supported and described in detail by density functional theory calculations,which revealed that surface Ti^(3+)states were the main catalytic *** is the first time that a detailed step-by-step mechanism at the atomic level has been proposed for this electrocatalytic reaction,which represents a valuable contribution to the understanding of this process of high energy/environmental *** is also the first time that black TiO_(2)has been used as an electrocatalyst for this sustainable process.

关键词： Chemical energy storage electrochemical hydrogenation Density functional theory Renewable energy Oxalic acid

Altered microRNA composition in the uterine lumen fluid in cattle(Bos taurus)pregnancies initiated by artificial insemination or transfer of an in vitro produced embryo

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Journal of Animal science and Biotechnology 2025年第1期16卷 76-91页

作者： Fernando H.Biase sarah e.Moorey Julie G.schnuelle soren Rodning Martha sofia Ortega Thomas e.spencer school of Animal sciences Virginia Polytechnic Institute and State University175 W Campus DrBlacksburgVA 24061USA Department of Animal science University of TennesseeKnoxvilleTN 37996USA Department of Clinical sciences Auburn UniversityAuburnAL 36849USA Department of Animal science Auburn UniversityAuburnAL 36849USA Department of Animal and Dairy sciences University of Wisconsin MadisonMadisonWI 53706USA Division of Animal sciences University of MissouriColumbiaMO 65211USA

Background MicroRNAs(miRNAs)are presented in the uterine lumen of many mammals,and in vitro experiments have determined that several miRNAs are important for the regulation of endometrial and trophoblast *** aim was to identify and contrast the miRNAs present in extracellular vesicles(eVs)in the uterine lumen fluid(ULF)at the onset of attachment in cattle pregnancies(gestation d 18)initiated by artificial insemination(AI)or by the trans-fer of an in vitro-produced blastocyst(IVP-eT).A third group had no conceptus after the transfer of an IVP *** The abundance of 263 annotated miRNAs was quantified in the eVs collected from *** was an increase in the transcript abundance of 20 miRNAs in the ULF eVs from the AI pregnant group,while 4 miRNAs had a lower abundance relative to the group not containing a ***,4 miRNAs were more abun-dant in ULF eVs in the AI pregnant group relative to IVP-eT group(bta-mir-17,bta-mir-7-3,MIR7-1,MIR18A).specific miRNAs in the ULF eVs were co-expressed with messenger RNAs expressed in extra-embryonic tissues and endome-trium,including genes that are known to be their *** The results provide biological insights into the participation of miRNAs in the regulation of trophoblast proliferation and differentiation,as well as in endometrium *** knowledge that in vitro cultured embryos can contribute to the altered abundance of specific miRNAs in the uterine lumen can lead to the development of cor-rective approaches to reduce conceptus losses during the first month of pregnancy in cattle.

关键词： Artificial reproductive technology Cattle Conceptus embryos endometrium small RNA

Abrasive wear behavior of functionally graded Al_(3)Ti reinforced aluminum matrix composite

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China Foundry 2025年第1期22卷 45-54页

作者： eylül Tuğçe Yaman Yildiz Ömer savaş Muhammed soner Başer engin Kocaman Ince shipping Group 34724IstanbulTurkey Yildiz Technical University Faculty of Naval Architecture and Maritime34349IstanbulTurkey Ministry of Transport and Infrastructure General Directorate of Marine Affairs06338AnkaraTurkey Zonguldak Bulent ecevit University Faculty of EngineeringDepartment of Aerospace Engineering67100ZonguldakTurkey

Aluminum alloys are widely used in industry due to their light *** alloys are generally exposed to abrasive wear,which diminishes their effective *** wear resistance of these alloys is enhanced by adding various reinforcements,however,this enhancement comes at the cost of reduced fracture *** paradox of increased wear resistance versus decreased fracture toughness in aluminum alloys can be resolved by using functionally graded materials (FGMs).This study focuses on the abrasive wear behavior of functional graded aluminum matrix composites reinforced with Al_(3)Ti *** wear properties of the composites were investigated by considering the characteristics of the composite such as matrix type and various composite zones,as well as the wear parameters such as abrasive particle diameter,load,sliding speed and *** method was used in the abrasive wear tests in order to get more reliable results in a timeefficient *** recipes were created based on the L_(27)(3^(6)) orthogonal *** a result of the study,it is observed that the wear resistance of the composites increases with an increase in Al_(3)Ti reinforcement content and hardness of the *** addition,the size of abrasive particles and the applied load are significant factors affecting abrasive wear.

关键词： functionally graded Al_(3)Ti Taguchi abrasive wear

Improving gastrointestinal scoring systems for predicting short-term mortality in critically ill patients

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World Journal of Gastroenterology 2025年第5期31卷 137-139页

作者： shane Moore Noel e Donlon Department of Anaesthesia and Critical Care University Hospital LimerickLimerick V94MunsterIreland Department of Upper Gastrointestinal surgery St James HospitalDublin D09LeinsterIreland

shen et al’s retrospective study aims to compare the utility of two separate scoring systems for predicting mortality attributable to gastrointestinal(GI)injury in critically ill patients[the GI Dysfunction score(GIDs)and the acute Gastroin-testinal Injury(AGI)grade].The authors note that this study is the first proposal that suggests an equivalence between the ability of both scores to predict mor-tality at 28 days from intensive care unit(ICU)*** et al retrospec-tively analysed an ICU cohort of patients utilising two physicians administering both the AGI grade and GIDs score,using electronic healthcare records and ICU *** these physicians disagreed about the scores,the final decision as to the scores was made by an associate chief physician,or chief *** note that the primary reason for the development of GIDs was to create a clear score for GI dysfunction,with minimal subjectivity or inter-operator *** subjectivity inherent to the older AGI grading system is what ultimately led to the development of GIDs in *** ensuring consensus between physicians administering the AGI,shen et al have controlled for one of this grading systems biggest *** have concerns,however,that this does not represent the real-world challenges associated with applying the AGI compared to the newer GIDs,and wonder if this arbitration process had not been instituted,would the two scoring systems remain equivalent in terms of predicted mortality?

关键词： Gastrointestinal injury Critical care Patient mortality prediction Gastrointe-stinal Dysfunction score acute Gastrointestinal Injury grade Intensive care unit scoring systems

enhancing Plant Resilience to Abiotic stress:The Power of Biostimulants

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Phyton-International Journal of experimental Botany 2025年第1期94卷 1-31页

作者： su-ee Lau Lucas Wei tze Lim Mohd Fadhli Hamdan Colin Chan Noor Baity saidi Janna Ong-Abdullah Boon Chin Tan Centre for Research in Biotechnology for Agriculture Universiti MalayaKuala Lumpur50603Malaysia Faculty of science Universiti MalayaKuala Lumpur50603Malaysia school of Biological sciences Universiti Sains MalaysiaGeorge Town11800Malaysia school of Biology Faculty of Applied SciencesUiTM Shah AlamShah Alam40450Malaysia Department of Biotechnology Faculty of Applied SciencesUCSI UniversityCheras56000Malaysia Department of Cell and Molecular Biology Faculty of Biotechnology and Biomolecular SciencesUniversiti Putra MalaysiaSerdang43400Malaysia

Abiotic stresses such as drought,heat,salinity,and heavy metal contamination severely affect global agricultural *** 2005 and 2015,droughts caused losses of approximately UsD 29 billion in developing countries,and from 2008 to 2018,droughts accounted for over 34%of crop and livestock yield losses,totaling about UsD 37 *** support the growing human population,agricultural output must increase substantially,necessitating a 60%–100%rise in crop productivity to meet the escalating *** address environmental challenges,organic,inorganic,and microbial biostimulants are increasingly employed to enhance plant resilience through various morphological,physiological,and biochemical *** biostimulants enhance plant resilience under abiotic stress through mechanisms such as abscisic acid signaling modulation,which regulates stomatal closure to reduce water loss during drought and heat ***,they aid in scavenging reactive oxygen species and stabilizing ion channels,mitigating oxidative damage,and maintaining ionic balance under stress conditions such as *** review summarizes recent advancements in applying these biostimulants,focusing on their roles in triggering morphological,physiological,biochemical,and molecular changes that collectively enhance plant resilience under stress *** also includes a bibliometric analysis of all articles published on biostimulants from 2019 to 2024 and explores future research *** was placed on optimizing biostimulant formulations and understanding their synergistic effects to maximize their efficacy under various stress *** integrating biostimulants into agricultural practices,we can adopt a sustainable strategy to safeguard crop productivity in the face of climate change and environmental stressors.

关键词： Abiotic stress crop improvement microbial plant growth promoting rhizobacteria protein hydrolysate seaweed