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Cross-method Analysis of Corotation Radii Data set for spiral Galaxies

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Research in Astronomy and Astrophysics 2024年第7期24卷 98-113页

作者： V.s.Kostiuk A.A.Marchuk A.s.Gusev sternberg Astronomical Institute Lomonosov Moscow State University Central (Pulkovo) Astronomical Observatory Russian Academy of Sciences saint Petersburg state University

A corotation radius is a key characteristic of disk galaxies that is essential to determine the angular speed of the spiral structure Ωp, and therefore understand its nature. In the literature, there are plenty of methods to estimate this value, but do these measurements have any consistency? In this work, we collected a data set of corotation radius measurements for 547 galaxies, 300 of which had at least two values. An initial analysis reveals that most objects have rather inconsistent corotation radius positions. Moreover, a significant fraction of galactic disks is distinguished by a large error coverage and almost uniform distribution of measurements. These findings do not have any relation to spiral type, Hubble classification, or presence of a bar. Among other reasons, obtained results could be explained by the transient nature of spirals in a considerable part of galaxies. We have made our collected data sample publicly available, and have demonstrated on one example how it could be useful for future research by investigating a winding time value for a sample of galaxies with possible multiple spiral arm patterns.

关键词： galaxies: fundamental parameters galaxies: kinematics and dynamics galaxies: structure

Two-stream Approximation to the Radiative Transfer Equation:A New Improvement and Comparative Accuracy with Existing Methods

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Advances in Atmospheric sciences 2024年第2期41卷 278-292页

作者： f.Momo TEMGOUA L.Akana NGUIMDO DNJOMO Environmental Energy Technologies Laboratory(EETL) Faculty of SciencesUniversity of YaoundéPO Box 812 YaoundéCameroon Department of Electrical and Electronic Engineering Faculty of Engineering and TechnologyUniversity of BueaPO Box 63 BueaCameroon

Mathematical modeling of the interaction between solar radiation and the Earth's atmosphere is formalized by the radiative transfer equation(RTE), whose resolution calls for two-stream approximations among other methods. This paper proposes a new two-stream approximation of the RTE with the development of the phase function and the intensity into a third-order series of Legendre polynomials. This new approach, which adds one more term in the expression of the intensity and the phase function, allows in the conditions of a plane parallel atmosphere a new mathematical formulation of γparameters. It is then compared to the Eddington, Hemispheric Constant, Quadrature, Combined Delta function and Modified Eddington, and second-order approximation methods with reference to the Discrete Ordinate(Disort) method(δ –128 streams), considered as the most precise. This work also determines the conversion function of the proposed New Method using the fundamental definition of two-stream approximation(f-TsA) developed in a previous work. Notably,New Method has generally better precision compared to the second-order approximation and Hemispheric Constant methods. Compared to the Quadrature and Eddington methods, New Method shows very good precision for wide domains of the zenith angle μ 0, but tends to deviate from the Disort method with the zenith angle, especially for high values of optical thickness. In spite of this divergence in reflectance for high values of optical thickness, very strong correlation with the Disort method(R ≈ 1) was obtained for most cases of optical thickness in this study. An analysis of the Legendre polynomial series for simple functions shows that the high precision is due to the fact that the approximated functions ameliorate the accuracy when the order of approximation increases, although it has been proven that there is a limit order depending on the function from which the precision is lost. This observation indicates that increasing the order of app

关键词： Radiative Transfer Equation two-stream method Legendre polynomial optical thickness moments of specific intensity conversion function transmittance reflectance

Dynamic and electrical responses of a curved sandwich beam with glass reinforced laminate layers and a pliable core in the presence of a piezoelectric layer under low-velocity impact

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 155-178页

作者： N.sHAHVEIsI s.fELI Department of Mechanical Engineering Razi UniversityKermanshah ***Iran

The dynamic responses and generated voltage in a curved sandwich beam with glass reinforced laminate(GRL)layers and a pliable core in the presence of a piezoelectric layer under low-velocity impact(LVI)are *** current study aims to carry out a dynamic analysis on the sandwich beam when the impactor hits the top face sheet with an initial *** the layer analysis,the high-order shear deformation theory(HsDT)and frostig's second model for the displacement fields of the core layer are *** classical non-adhesive elastic contact theory and Hunter's principle are used to calculate the dynamic responses in terms of *** order to validate the analytical method,the outcomes of the current investigation are compared with those gained by the experimental tests carried out by other researchers for a rectangular composite plate subject to the *** element(fE)simulations are conducted by means of the ABAQUs *** effects of the parameters such as foam modulus,layer material,fiber angle,impactor mass,and its velocity on the generated voltage are reviewed.

关键词： analytical model piezoelectric layer curved sandwich beam glass reinforced laminate(GRL) pliable core low-velocity impact(LVI) classical non-adhesive elastic contact theory

Glyphosate as a direct or indirect activator of pro-inflammatory signaling and cognitive impairment

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Neural Regeneration Research 2024年第10期19卷 2212-2218页

作者： Yukitoshi Izumi Kazuko A.O'Dell Charles f.Zorumski Department of Psychiatry Washington University School of MedicineSt.LouisMOUSA Taylor family Institute for Innovative Psychiatric Research Washington University School of MedicineSt.LouisMOUSA

Glyphosate-based herbicides are widely used around the world, making it likely that most humans have significant exposure. Because of habitual exposure, there are concerns about toxicity including neurotoxicity that could result in neurological, psychiatric, or cognitive impairment. We recently found that a single injection of glyphosate inhibits long-term potentiation, a cellular model of learning and memory, in rat hippocampal slices dissected 1 day after injection, indicating that glyphosate-based herbicides can alter cognitive function. Glyphosate-based herbicides could adversely affect cognitive function either indirectly and/or directly. Indirectly, glyphosate could affect gut microbiota, and if dysbiosis results in endotoxemia(leaky gut), infiltrated bacterial by-products such as lipopolysaccharides could activate pro-inflammatory cascades. Glyphosate can also directly trigger pro-inflammatory cascades. Indeed, we observed that acute glyphosate exposure inhibits long-term potentiation in rat hippocampal slices. Interestingly, direct inhibition of long-term potentiation by glyphosate appears to be similar to that of lipopolysaccharides. There are several possible measures to control dysbiosis and neuroinflammation caused by glyphosate. Dietary intake of polyphenols, such as quercetin, which overcome the inhibitory effect of glyphosate on long-term potentiation, could be one effective strategy. The aim of this narrative review is to discuss possible mechanisms underlying neurotoxicity following glyphosate exposure as a means to identify potential treatments.

关键词： cognitive impairment glyphosate microglia neuroinflammation roundup toll-like receptor 4 zinc chelation

MXenes for Bioinspired soft Actuators:Advancements in Angle-Independent structural Colors and Beyond

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Nano-Micro Letters 2024年第8期16卷 18-34页

作者： siavash Iravani Rajender s.Varma Independent Researcher W Nazar STBoostan AveIsfahanIran Centre of Excellence for Research in sustainable Chemistry Department of ChemistryFederal University of São CarlosSão CarlosSP 13565‑905Brazil

soft actuators have garnered substantial attention in current years in view of their potential appliances in diverse domains like robotics,biomedical devices,and biomimetic *** actuators mimic the natural movements of living organisms,aiming to attain enhanced flexibility,adaptability,and *** the other hand,angle-independent structural color has been achieved through innovative design strategies and engineering *** carefully controlling the size,shape,and arrangement of nanostructures,researchers have been able to create materials exhibiting consistent colors regardless of the viewing *** promising class of materials that holds great potential for bioinspired soft actuators is MXenes in view of their exceptional mechanical,electrical,and optical *** integration of MXenes for bioinspired soft actuators with angle-independent structural color offers exciting *** material compatibility issues,improving color reproducibility,scalability,durability,power supply efficiency,and cost-effectiveness will play vital roles in advancing these *** perspective appraises the development of bioinspired MXene-centered soft actuators with angleindependent structural color in soft robotics.

关键词： MXenes MXene-based composites Bioinspired soft robotics Angle-independent structural color

The outcomes and safety of patients undergoing endoscopic retrograde cholangiopancreatography combining a single-use cholangioscope and a single-use duodenoscope:A multicenter retrospective international study

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 71-76页

作者： Alessandro fugazza Matteo colombo Michel Kahaleh V.Raman Muthusamy Bick Benjamin Wim Laleman Carmelo Barbera Carlo fabbri Jose Nieto Abed Al-Lehibi Mohan Ramchandani Amy Tyberg Haroon shahid Avik sarkar Dean Ehrlich stuart shermand Cecilia Binda Marco spadaccini Andrea Iannone Kareem Khalaf Nageshwar Reddy Andrea Anderloni Alessandro Repici Division of Gastroenterology and Digestive Endoscopy Humanitas Research Hospital-IRCCSVia Manzoni 5620089RozzanoMilanoItaly Gastroenterology Rutgers Robert Wood JohnsonNew BrunswickNew JerseyUSA Vatche and Tamar Manoukian Division of Digestive Diseases University of CaliforniaLos Angeles School of Medicine at UCLALos AngelesCaliforniaUSA Division of Digestive and Liver Disorders Indiana University School of MedicineIndianapolisINUSA Department of Gastroenterology and Hepatology University Hospitals LeuvenKU Leuven3000 LeuvenBelgium U.O.C.di Gastroenterologia ed Endoscopia Digestiva Ospedale Giuseppe MazziniASL TeramoItaly Gastroenterology and Digestive Endoscopy Unit Forlì-Cesena HospitalsAUSL RomagnaForlì-CesenaItaly Borland Groover Clinic JacksonvilleFloridaUSA Department of Gastroenterology and Hepatology King Fahad Medical CityRiyadhSaudi Arabia Asian Institute of Gastroenterology HyderabadIndia section of Gastroenterology Department of Emergency and Organ TransplantationUniversity of BariBari 70124Italy Department of Biomedical sciences Humanitas UniversityVia Rita Levi Montalcini 420090Pieve EmanueleMilanItaly

Background: Duodenoscope-related multidrug-resistant organism(MDRO) infections raise concerns. Disposable duodenoscopes have been recently introduced in the market and approved by regulatory agencies with the aim to reduce the risk of endoscopic retrograde cholangiopancreatography(ERCP) associated infections. The aim of this study was to evaluate the outcome of procedures performed with single-use duodenoscopes in patients with clinical indications to single-operator cholangiopancreatoscopy. Methods: This is a multicenter international, retrospective study combining all patients who underwent complex biliopancreatic interventions using the combination of a single-use duodenoscope and a single-use cholangioscope. The primary outcome was technical success defined as ERCP completion for the intended clinical indication. secondary outcomes were procedural duration, rate of cross-over to reusable duodenoscope, operator-reported satisfaction score(1 to 10) on performance rating of the single-use duodenoscope, and adverse event(AE) rate. Results: A total of 66 patients(26, 39.4% female) were included in the study. ERCP was categorized according to AsGE ERCP grading system as 47(71.2%) grade 3 and 19(28.8%) grade 4. The technical success rate was 98.5%(65/66). Procedural duration was 64(interquartile range 15-189) min, cross-over rate to reusable duodenoscope was 1/66(1.5%). The satisfaction score of the single-use duodenoscope classified by the operators was 8.6 ± 1.3 points. four patients(6.1%) experienced AEs not directly related to the single-use duodenoscope, namely 2 post-ERCP pancreatitis(PEP), 1 cholangitis and 1 ***: single-use duodenoscope is effective, reliable and safe even in technically challenging procedures with a non-inferiority to reusable duodenoscope, making these devices a viable alternative to standard reusable equipment.

关键词： single-operator cholangioscopy single-use duodenoscope Endoscopic retrograde cholangiopancreatography Indeterminate biliary stricture Difficult biliary stones

Tensor force impact on shell evolution in neutron-rich si and Ni isotopes

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Chinese Physics C 2024年第4期48卷 95-106页

作者： s.V.sidorov A.s.Kornilova T.Yu.Tretyakova faculty of Physics Lomonosov Moscow State UniversityMoscow 119991Russia skobeltsyn Institute of Nuclear Physics Lomonosov Moscow State UniversityMoscow 119991Russia

The influence of the tensor interaction of nucleons on the characteristics of neutron-rich silicon and nickel isotopes was studied in this *** forces are considered within the framework of the Hartree-fock approach with the skyrme *** addition of a tensor component of interaction is shown to improve the description of the splittings between different single-particle states and decrease nucleon-nucleon pairing correlations in silicon and nickel *** attention was directed toward the role of isovector tensor forces relevant to the interaction of like nucleons.

关键词： nuclear shell model tensor interaction silicon isotopes nickel isotopes

survival and risk analysis of patients with COVID-19 in Iran

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Journal of Acute Disease 2024年第2期13卷 60-66页

作者： Mottaghipoor f Heidari Z sami R Memarzadeh H saghaeiannejad Isfahani s Department of Management and Health Information Technology Isfahan University of Medical SciencesIsfahanIran Department of Biostatistics and Epidemiology Isfahan University of Medical SciencesIsfahanIran Department of Internal Medicine School of MedicineIsfahan University of Medical SciencesIsfahanIran software Engineering Isfahan University of Medical SciencesIsfahanIran Health Information Technology Research Center Isfahan University of Medical SciencesIsfahanIran

Objective:To evaluate the risk factors of death caused by COVID-19 in ***:This study was a retrospective cohort study from february 20,2020,to August 22,2022,in the hospitals in Isfahan,*** data were collected through a researcher-made *** determine the risk factors of the death,logistic regression and Cox regression models were *** each variable,the odds ratio and 95%confidence interval were also ***:1885 Patients were *** age of deceased persons was significantly higher than that of the surviving *** risk of death for the age group above 60 years was about 14 times higher than that of people aged 19-35 years[95%CI:14.41(2.02-102.99),Psion[95%CI:1.92(1.47-2.5),Ps[95%CI:1.62(1.23-2.13),Pstructive pulmonary disease[95%CI:1.92(1.47-2.50),Pso risk factors of ***:This study reveals that the mortality rate due to COVID-19 is associated with old age,longer hospitalization in the ICU,increased length of stay,and comorbidities of high blood pressure,diabetes,and chronic pulmonary disease.

关键词： Cause Death survival COVID-19 Risk factors Iran

A Review on the Recent Trends of Image steganography for VANET Applications

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Computers, Materials & Continua 2024年第3期78卷 2865-2892页

作者： Arshiya s.Ansari Department of Information Technology College of Computer and Information SciencesMajmaah UniversityAl-Majmaah11952Saudi Arabia

Image steganography is a technique of concealing confidential information within an image without dramatically changing its outside *** vehicular ad hoc networks(VANETs),which enable vehicles to communicate with one another and with roadside infrastructure to enhance safety and traffic flow provide a range of value-added services,as they are an essential component of modern smart transportation *** steganography has been suggested by many authors for secure,reliable message transfer between terminal/hope to terminal/hope and also to secure it from attack for privacy *** paper aims to determine whether using steganography is possible to improve data security and secrecy in VANET applications and to analyze effective steganography techniques for incorporating data into images while minimizing visual quality *** to simulations in literature and real-world studies,Image steganography proved to be an effectivemethod for secure communication on VANETs,even in difficult network *** this research,we also explore a variety of steganography approaches for vehicular ad-hoc network transportation systems like vector embedding,statistics,spatial domain(sD),transform domain(TD),distortion,masking,and *** study possibly shall help researchers to improve vehicle networks’ability to communicate securely and lay the door for innovative steganography methods.

关键词： steganography image steganography image steganography techniques information exchange data embedding and extracting vehicular ad hoc network(VANET) transportation system