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A novel non-invasive model to predict high-risk varices in cirrhotic patients

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Hepatobiliary surgery and Nutrition 2024年第3期13卷 530-532页

作者： Kelvin K.C.ng Department of surgery The Chinese University of Hong Kong Medical CentreHong KongChina

Acute variceal bleeding is one of the most common and potentially life-threatening complications in patients with liver *** is conventionally diagnosed by oesophagogastroduodenoscopy,which.is invasive to patients and carries hospital *** would be more cost-effective if non-invasive tests could screen out high-risk patients who developed acute variceal bleeding requiring endoscopic *** can potentially reduce the need for invasive procedures for cirrhotic *** recent years,there have been advancements in non-invasive methods for assess.ng the risk of variceal *** include transient elastography(Fibroscan)of the liver and spleen,platelet count,imaging modalities[ultrasound or magnetic resonance imaging(MRi)],and non-invasive liver function tests[child-Pugh score or the Model for End-stage Liver Disease(MELD)score].The 2015 Baveno Vi consensus is developed by an international panel of experts to improve the diagnosis and management of portal hypertension and its complications,specifically focus.ng on variceal bleeding in patients with cirrhosis(1).The consensus emphasizes us.ng noninvasive methods to screen out high-risk varices(HRV)requiring therapeutic *** key features of the Baveno Vi criteria include a liver stiffness measurement(LsM)150,000/*** can confidently rule out *** has been proven to avoid unnecessary endoscopy up to 40%with a specificity of up to 46%(2).in recent years,spleen stiffness measurement(ssM)has been a useful tool to assess portal hypertension and to predict ***,the revised Baveno Vii consensus in 2022 recommends ssM≤40 kPa would avoid more unnecessary endoscopy in patients who fall outside Baveno Vi criteria,with a missed HRV rate of<5%(3).

关键词： Non-invasive model high-risk varices cirrhosis

Nuclear volume effects in kinetic isotope fractionation:A case study of mercury oxidation by chlorine species

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Acta Geochimica 2024年第3期43卷 411-423页

作者： chenlu Yang Yining Zhang yun Liu Research Center for Planetary science College of Earth and Planetary SciencesChengdu University of TechnologyChengdu 610059China state Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

it is well-known that the equilibrium isotope fractionation of mercury(Hg)includes classical massdependent fractionations(MDFs)and nuclear volume effect(NVE)induced mass-independent fractionations(MiFs).However,the effect of the NVE on these kinetic processes is not *** total fractionations(MDFs+NVEinduced MiFs)of several representative Hg-incorporated substances were selected and calculated with ab initio calculations in this work for both equilibrium and kinetic ***-induced MiFs were calculated with scaled contact electron densities at the nucleus through systematic evaluations of their accuracy and errors us.ng the Gaussian09 and DiRAC19 packages(named the electron density scaling method).Additionally,the NVE-induced kinetic isotope effect(KiE)of Hg isotopes are also calculated with this method for several representative Hg oxidation reactions by chlorine *** KiEs for 202 Hg/^(198)Hg ranging from−2.27‰to 0.96‰are *** anomalous^(202)Hg-enriched KiEs(δ^(202)Hg/^(198)Hg=0.83‰,0.94‰,and 0.96‰,)caused by the NVE are observed,which are quite different from the classical view(i.e.,light isotopes react faster than the heavy ones).The electron density scaling method we developed in this study can provide an easier way to calculate the NVE-induced KiEs for heavy isotopes and serve to better understand the fractionation mechanisms of mercury isotope systems.

关键词： Nuclear volume effect Kinetic fractionation Hg isotopes Ab initio calculations

Capture Efficiency Analysis in the Circular Restricted Three-body Problem

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Research.in Astronomy and Astrophysics 2024年第5期24卷 198-210页

作者： Yu-Xuan Miao Xi-yun Hou Department of Astronomy and space science Nanjing UniversityNanjing 210023China institute of space Environment and Astrodynamics Nanjing UniversityNanjing 210023China Key Laboratory of Modern Astronomy and Astrophysics Ministry of EducationNanjing 210023China

Temporary capture efficiency is studied in the framework of the circular restricted three-body problem in two ***, a non-uniform distribution of test particles around the secondary's orbit is obtained by fully accounting the secondary's gravitational influence. second, the capture efficiency is computed based on the non-uniform distribution. several factors influencing the result are discussed. By studying the capture efficiency in the circular restricted three-body problem of different mass ratios, a power-law relation between the capture efficiency(p) and the mass ratio(μ) is established, which.is given by p ≈ 0.27 × μ^(0.53), within the range of 3.0035 ×10^(-6)≤ μ ≤ 3.0034 × 10^(-5). Taking the sun–Earth system as an example, the influence from the orbit eccentricity of the secondary on the non-uniform distribution and the capture efficiency is studied. Our studies find that the secondary's orbit eccentricity has a negative influence on the capture efficiency.

关键词： methods numerical-celestial mechanics-planets and satellites dynamical evolution and stability

Low-molecular-weight fucoidan inhibits the proliferation of melanoma via Bcl-2 phosphorylation and PTEN/AKT pathway

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Oncology Research 2024年第2期32卷 273-282页

作者： MiNJi PARK chULHWAN BAng WON-sOO yun yun-Mi JEOng T&R Biofab Co. Ltd.Seongnam-si13487Korea Department of Dermatology Seoul St.Mary’s HospitalCollege of MedicineThe Catholic University of KoreaSeoul02706Korea Department of Mechanical Engineering Tech University of KoreaSi-heung City15073Korea

Fucoidan,a sulfate polysaccharide obtained from brown seaweed,has various bioactive properties,including anti-inflammatory,anti-cancer,anti-viral,anti-oxidant,anti-coagulant,anti-thrombotic,anti-angiogenic,and anti-Helicobacter pylori ***,the effects of low-molecular-weight fucoidan(LMW-F)on melanoma cell lines and three dimensional(3D)cell culture models are not well *** study aimed to investigate the effects of LMW-F on A375 human melanoma cells and cryopreserved biospecimens derived from patients with advanced *** wave was used to fragment fucoidan derived from Fucus vesiculosus into smaller *** and live/dead assays showed that LMW-F inhibited cell proliferation in both A375 cells and patientderived melanoma explants in a 3D-printed collagen *** PTEN/AKT pathway was found to be involved in the anti-melanoma effects of *** blot analysis revealed that LMW-F reduced the phosphorylation of Bcl-2 at Thr 56,which was associated with the prevention of anti-apoptotic activity of cancer *** findings suggested that LMW-F could enhance anti-melanoma chemotherapy and improve the outcomes of patients with melanoma resistance.

关键词： Low-molecular-weight fucoidan Melanoma Patient-derived melanoma explants in a 3D-printed collagen scaffold Anti-melanoma effect PTEN-AKT-Bcl-2 network

Mg/MgO interfaces as efficient hydrogen evolution cathodes caus.ng accelerated corrosion of additive manufactured Mg alloys:A DFT analysis

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Journal of Magnesium and Alloys 2024年第1期12卷 110-119页

作者： Man-Fai ng Kai Xiang Kuah Teck Leong Tan Daniel John Blackwood Department of Materials science&Engineering National University of Singapore9 Engineering Drive 1Singapore 117575Republic of Singapore institute of High Performance Computing(iHPC) Agency for ScienceTechnology and Research(A∗STAR)1 Fusionopolis Way#16-16 ConnexisSingapore 138632Republic of Singapore

The corrosion rates of additive-manufactured Mg alloys are higher than their as-cast counterparts,possibly due to increased kinetics for the hydrogen evolution reaction on secondary phases,which may include oxide *** Kelvin Probe Force Microscopy demonstrated that MgO inclusions could act as cathodes for Mg corrosion,but their low conductivity likely precludes ***,the density of state calculations through density functional theory us.ng hybrid HsE06 functional revealed overlapping electronic states at the Mg/MgO interface,which facilitates electron transfers and participates in redox *** determination of the hydrogen absorption energy at the Mg/MgO interface reveals it to be an excellent catalytic site,with HER being found to be a factor of 23x more efficient at the interface than on metallic *** results not only support the plausibility of the Mg/MgO interface being an effective cathode to the adjacent anodic Mg matrix during corrosion but also contribute to the understanding of the enhanced cathodic activities observed during the anodic dissolution of magnesium.

关键词： Magnesium Magnesium oxide interface Hydrogen evolution DFT

Developmental impacts and toxicological hallmarks of silver nanoparticles across diverse biological models

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Environmental science and Ecotechnology 2024年第3期19卷 60-79页

作者： Yán Wāng Yapeng Han De-Xiang Xu Department of Toxicology School of Public Health&Key Laboratory of Environmental Toxicology of Anhui Higher Education InstitutesAnhui Medical UniversityHefei230032China

silver nanoparticles(AgNPs),revered for their antimicrobial prowess,have become ubiquitous in a range of products,from biomedical equipment to food ***,amidst their ris.ng popularity,concerns loom over their possible detrimental effects on fetal development and subsequent adult *** review delves into the developmental toxicity of AgNPs across diverse models,from aquatic species like zebrafish and catfish to mammalian rodents and in vitro embryonic stem *** focus encompasses the fate of AgNPs in different contexts,elucidating associated hazardous results such as embryotoxicity and adverse pregnancy ***,we scrutinize the enduring adverse impacts on offspring,spanning impaired neurobehavior function,reproductive disorders,cardiopulmonary lesions,and *** hallmarks of developmental harm are identified,encompass.ng redox imbalances,inflammatory cascades,DNA damage,and mitochondrial ***,we explore potential explanations,linking immunoregulatory dysfunction and disrupted epigenetic modifications to AgNPsinduced developmental *** substantial progress,our understanding of the developmental risks posed by AgNPs remains incomplete,underscoring the urgency of further research.in this critical area.

关键词： silver nanoparticles(AgNPs) Developmental toxicity Maternal exposure Fetal development Redox imbalance Mitochondrial dysfunction

Highly divergent sympatric lineages of Leptotila verreauxi(Aves:Columbidae)suggest a secondary contact area in the isthmus of Tehuantepec,Mexico

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Avian Research 2024年第1期15卷 12-21页

作者： Orlando J.Espinosa-chávez Adolfo G.Navarro-sigüenza Hernando Rodríguez-Correa Luis A.sánchez-González Museo de Zoología“Alfonso L.Herrera” Depto.de Biología EvolutivaFacultad de CienciasUniversidad Nacional Autonoma de MexicoApdo.Postal 70-399CP 04510Ciudad de MexicoMexico Posgrado en Ciencias Biologicas Unidad de PosgradoEdificio D1◦PisoCircuito de PosgradosCiudad UniversitariaUniversidad Nacional Autonoma de MexicoCoyoacanCP 04510CDMXMexico Escuela Nacional de Estudios superiores Unidad Morelia Universidad Nacional Autonoma de Mexico.Antigua Carretera a Patzcuaro No.8701 Col.Ex Hacienda de San Jose de la HuertaC.P.58190MoreliaMichoacanMexico

Due to a complex geological and biotic history,the isthmus of Tehuantepec(iT),has been long recognized as a driver for the evolutionary divergence of numerous lowland and highland *** distributed in the lowlands of the American continent,the White-Tipped Dove(Leptotila verreauxi)is a polytypic species with 13 recognized *** of these have been recorded in Mexico,and the distribution of three abuts at the iT,suggesting a contact *** estimate phylogenetic patterns,divergence times and genetic differentiation,we examined two mt DNA(ND2 and COi)and one n DNA(β-fibint 7)*** also used correlative ecological niche models(ENM)to assess whether ecological differences across the iT may have acted as a biogeographical *** estimated paleodistributions during the Middle Holocene,Last Glacial Maximum and Last interglacial,to evaluate the influence of climate changes on the distribution and demographic *** results showed genetically distinct lineages that diverged approximately 2.5 million years *** and ecological factors may have played a dual role in promoting differentiation,but also in the formation of a secondary contact zone in the southern *** ecological niche comparisons indicated that the ecological niche of sympatric lineages at the iT are not identical,suggesting niches divergence;in addition,environmental niche models across the region indicated no abrupt biogeographic barriers,but the presence of regions with low *** results suggest that genetic differentiation originated by a vicariant event probably related to environmental factors,favored the evolution of different ecological ***,the absence of a biogeographic barrier but the presence of less suitable areas in the contact regions,suggest that secondary contact zones may be also maintained by climatic factors for the eastern group,but also by biotic interactions for the western group.

关键词： Biogeographical boundary Humid and dry forests isthmus of Tehuantepec Phylogeography secondary contact

Mechanical Performance of Bio-inspired Bidirectional Corrugated sandwich Pressure shell Under External Hydrostatic Pressure

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china Ocean Engineering 2024年第2期38卷 297-312页

作者： ZHAng Yi chEN Yue yun Lai LiAng Xu Ocean College Zhejiang UniversityZhoushan 316000China Hainan institute Zhejiang UniversitySanya 572000China

This paper aims to enhance the compression capacity of underwater cylindrical shells by adopting the corrugated sandwich structure of *** cuttlebone suffers uniaxial external compression,while underwater cylindrical shells are in a biaxial compressive stress *** suit the biaxial compressive stress state,a novel bidirectional corrugated sandwich structure is proposed to improve the bearing capacity of cylindrical *** static and buckling analysis for the sandwich shell and the unstiffened cylindrical shell with the same volume-weight ratio are studied by numerical *** is indicated that the proposed sandwich shell can effectively reduce the ratio between circumferential and axial stress from 2 to 1.25 and improve the critical buckling load by about 1.63 *** simulation shows that optimizing and adjusting the structural parameters could significantly improve the advantage of the sandwich ***,the hydrostatic pressure tests for shell models fabricated by 3D printing are carried *** to the experimental results,the overall failure position of the sandwich shell is at the center part of the sandwich *** has been found the average critical load of the proposed sandwich shell models exceeds two times that of the unstiffened shell ***,the proposed bio-inspired bidirectional corrugated sandwich structure can significantly enhance the pressure resistance capability of cylindrical shells.

关键词： bio-inspiration bidirectional corrugation sandwich shell external pressure buckling

Adversarial attacks and defenses for digital communication signals identification

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Digital Communications and Networks 2024年第3期10卷 756-764页

作者： Qiao Tian sicheng Zhang shiwen Mao yun Lin College of Computer science and Technology Harbin Engineering UniversityHarbin150001China College of information and Communication Engineering Harbin Engineering UniversityHarbin150000China Department of Electrical and Computer Engineering Auburn UniversityAuburnAL36849USA

As modern communication technology advances apace,the digital communication signals identification plays an important role in cognitive radio networks,the communication monitoring and management *** has become a promis.ng solution to this problem due to its powerful modeling capability,which has become a consensus in academia and ***,because of the data-dependence and inexplicability of Ai models and the openness of electromagnetic space,the physical layer digital communication signals identification model is threatened by adversarial *** examples pose a common threat to Ai models,where well-designed and slight perturbations added to input data can cause wrong ***,the security of Ai models for the digital communication signals identification is the premise of its efficient and credible *** this paper,we first launch adversarial attacks on the end-to-end Ai model for automatic modulation classifi-cation,and then we explain and present three defense mechanisms based on the adversarial *** we present more detailed adversarial indicators to evaluate attack and defense ***,a demonstration verification system is developed to show that the adversarial attack is a real threat to the digital communication signals identification model,which should be paid more attention in future research.

关键词： Digital communication signals identification Ai model Adversarial attacks Adversarial defenses Adversarial indicators