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层状渗透介质中地震导波的散射和衰减

石油物探译丛 1995年第1期 74-80页

作者： j.o.parra 杨红霞

根据Biot理论和均匀性理论分析了流体饱和孔隙介质中波的传播,可计算低速层介质中地震导波的散射和衰减。根据本构关系,平衡方程和改进Biot理论后的广义Darcy定律,可求出各种方程的耦合系统,其中的每个方程都控制着每层中波的运动。位... 详细信息

根据Biot理论和均匀性理论分析了流体饱和孔隙介质中波的传播,可计算低速层介质中地震导波的散射和衰减。根据本构关系,平衡方程和改进Biot理论后的广义Darcy定律,可求出各种方程的耦合系统,其中的每个方程都控制着每层中波的运动。位移场和应力场都满足界面上引力和位移连续性边界条件和无限远点散射的条件。为避免单个矩阵中大波数呈指数增长时出现的精度问题,我们采用全局矩阵法代替常规传播法来估计散射和衰减的关系。这一研究结果表明,导波的衰减对于目的层渗透性是灵敏的,尤其是当低速层的渗透性在群速度最小Airy相位处变化时,衰减的变化很大。

关键词：散射衰减地震波地震勘探油气勘探

Gram-negative bacterial diversity and evidence of international clones of multidrug-resistant strains in zoo animals

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Integrative Zoology 2024年第3期19卷 417-423页

作者： joão Pedro Rueda FURLAN Micaela Santana RAMoS Fábio parra SELLERA Irys Hany Lima GoNZALEZ Patrícia Locosque RAMoS Eliana Guedes STEHLING Department of Clinical Analyses Toxicology and Food ScienceSchool of Pharmaceutical Sciences of Ribeirão PretoUniversity of São PauloRibeirão PretoBrazil Department of Internal Medicine School of Veterinary Medicine and Animal ScienceUniversity of São PauloSão PauloBrazil School of Veterinary Medicine Metropolitan University of SantosSantosBrazil Coordination of Wild Fauna Secretary of EnvironmentInfrastructure and LogisticsSão PauloBrazil

Antimicrobial resistance(AMR)is a growing phenomenon that poses a major public health challenge worldwide(Dhingra et al.2020;Antimicrobial Resistance Collaborators 2022).The selective pressure exerted in clinical settings has contributed to the longlasting successful dissemination of multidrug-resistant(MDR)Gram-negative bacteria in these environments(Chia et al.2020).

关键词： multidrug clinical

Endoscopic treatment of scarred polyps with a non-thermal device(Endorotor):A review of the literature

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World journal of Gastroenterology 2024年第12期30卷 1706-1713页

作者： Mariam Zaghloul Hameed Rehman Stefano Sansone Konstantinos Argyriou Adolfo parra-Blanco Department of Hepatology Gastroenterology and Infectious DiseasesKafrelsheikh UniversitKafr-Elshikh 33516Egypt Department of Gastroenterology Service Nottingham City Hospital CampusNottingham University Hospitals NHS TrustNottingham NG51PBUnited Kingdom Department of Gastroenterology University Hospital of LarissaLarissa 41334Greece NIHR Nottingham Biomedical Research Centre Nottingham University Hospitals NHS Trust and University of NottinghamNottingham NG72UHUnited Kingdom

Endoscopic resection(ER)of colorectal polyps has become a daily practice in most endoscopic units providing a colorectal cancer screening program and requires the availability of local experts and high-end endoscopic *** procedures have evolved over the past few years from endoscopic mucosal resection(EMR)to more advanced techniques,such as endoscopic submucosal dissection and endo-scopic full-thickness *** resection and disease eradication are the ultimate goals of ER-based techniques,and novel devices have been developed to achieve these *** EndoRotor®Endoscopic Powered Resection System(Interscope Medical,Inc.,Northbridge,Massachusetts,United States)is one such *** EndoRotor is a powered resection tool for the removal of alimentary tract mucosa,including post-EMR persistent lesions with scarring,and has both CE Mark and FDA *** review covers available published evidence documenting the usefulness of EndoRotor for the management of recurrent colorectal polyps.

关键词： EndoRotor Scarred polyps Recurrent polyps Colorectal cancer Colorectal polyps

Breaking paradigms: Long non-coding RNAs forming gene fusions with potential implications in cancer

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Genes & Diseases 2024年第3期11卷 311-323页

作者： David Sanchez-Marin Macrina Beatriz Silva-Cazares Fany Iris Porras-Reyes Rebeca Garcia-Roman Alma D.Campos-parra Posgrado en Ciencias Biologicas Facultad de MedicinaUniversidad Nacional Autonoma de MexicoCiudad de MexicoC.P.04360Mexico Unidad Academica Multidisciplinaria Region Altiplano Universidad Autonoma de San Luis Potost(UASLP)Carretera a Cedral Km 5+600Ejido San Jose de la TrojesMatehualaSan Luis PotosiC.P.78760Mexico Servicio de Anatomia Patologica Instituto Nacional de Cancerologia(INCan)Nino JesuisTlalpanCiudaddeMexicoC.P.14080Mexico Instituto de Salud Publica Universidad Veracruzana(UV)Av.Dr LuisDr.Castelazo Ayala s/nCol.Industrial AnimasXalapaVeracruzC.P.91190Mexico

Long non-coding RNAs(lncRNAs)are non-coding RNAs longer than 200 nucleotides with dynamic regulatory *** interact with a wide range of molecules such as DNA,RNA,and proteins to modulate diverse cellular functions through several mechanisms and,if deregulated,they can lead to cancer development and ***,it has been described that IncRNAs are susceptible to form gene fusions with mRNAs or other IncRNAs,breaking the paradigm of gene fusions consisting mainly of protein-coding ***,their biological significance in the tumor phenotype is still ***,their recent identification opens a new line of research to study their biological role in tumor-igenesis,and their potential as biomarkers with clinical relevance or as therapeutic *** present study aimed to review the IncRNA fusions identified so far and to know which of them have been associated with a potential *** address the current challenges to deepen their study as well as the reasons why they represent a future therapeutic window incancer.

关键词： Cancer Genefusions IncRNAs ncRNAs Therapy

on the analytical solution of transient friction in channel flows

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1447-1466页

作者： F.j.GARCíA-GARCíA P.FARI?AS-ALVARI?o Department of Naval & Industrial Engineering Polytechnic School of EngineeringUniversity of A Coru?a Campus Industrial de Ferrol Integraciones Técnicas de Seguridad S.A. Pol.Ind.Espíritu Santo

The transient friction in channel mean flows is the sum of two contributions,i.e., the underlying laminar flow(ULF) and the purely turbulent component(PTC), and the contributions are analyzed separately by theoretical experiments. It is found that,the transient friction may be higher or remarkably lower than that in equal-Reynolds number steady-state flows. The universal time constant for plane-parallel laminar flows is reported, and the role of the time constant in a turbulent mean flow is examined. It is shown that the time constant is related to the turbulence's frozen time. Finally, a study of the logarithmic layer during the transient flow is accomplished, which shows that the logarithmic layer is destroyed.

关键词： 76D05 76D06 76F55 o361 transient flow transient friction unsteady channel flow

A prototype for on-site generation of chlorinated disinfectant for use in rural aqueducts

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Water Science and Engineering 2024年第1期17卷 33-40页

作者： Diana Marcela Cuesta parra Felipe Correa Mahecha Andrés Felipe Rubio Pinzon Davidcamilo Ramirez Bustos Leonel Alveyro Teran Llorente Miguel Fernando jimenez jimenez Chemical and Environmental Engineering Department Fundacion Universidad de AmericaBogota 117111Colombia Chemical Engineering Department Fundacion Universidad de AmericaBogota 117111Colombia Mecanical Engineering Department Fundacion Universidad de AmericaBogota 117111Colombia

Sodium hypochlorite has significant potential as a sanitation solution in hard-to-reach *** studies have investigated the optimal electrolysis parameters for its production with volumes greater than 1o *** study evaluated sodium hypochlorite production through electrolysis in a 22-L prototype and identified the optimal operating *** were performed using graphite electrodes with areas of 68.4 cm^(2) at the laboratory scale and 1865.0 cm^(2) at the prototype scale.A design for experiments with different operating times,chloride concentrations,and electric current intensities was *** optimal operating time,sodium chloride concentration,and current intensity at the laboratory scale were 120 min,150 g of chloride per liter,and 3 A,respectively,leading to the production of 5.02 g/L of the disinfectant with an energy efficiency of 12.21 mg of Cl_(2) per *** the prototype scale,the maximum sodium hypochlorite concentration of 3.99 g of chloride per liter was achieved with an operating time of 120 min,a sodium chloride concentration of 100 g of chloride per liter,and a current intensity of 70 A,reaching an energy efficiency of 42.56 mg of Cl_(2) per *** addition,this study evaluated the influences of the chloride concentration,current intensity,and operating time on the production of sodium hypochlorite at the two scales,and formulated the equations showing the trends of sodium hypochlorite production and energy efficiency in the electrochemical *** 22-L prototype model for production of this oxidizing substance is promising for disinfection of large volumes of water in areas that are difficult to access.

关键词： Disinfection Electrolysis Energy efficiency optimization Sodium hypochlorite

Chiral forces in longitudinally invariant dielectric photonic waveguides

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Photonics Research 2024年第3期12卷 431-443页

作者： joSEP MARTÍNEZ-RoMEU IAGo DIEZ SEBASTIAN GoLAT FRANCISCo j.RoDRÍGUEZ-FoRTUÑo ALEjANDRo MARTÍNEZ Nanophotonics Technology Center Universitat Politècnica de ValènciaValencia 46022Spain Department of Physics King’s College LondonLondon WC2R 2LSUK

We calculate numerically the optical chiral forces in rectangular cross-section dielectric waveguides for potential enantiomer *** study considers force strength and time needed for separating chiral nanoparticles,mainly via quasi-TE guided modes at short wavelengths(405 nm)and the 90°-phase-shifted combination of quasi-TE and quasi-TM modes at longer wavelengths(1310 nm).Particle tracking simulations show successful enantiomer separation within two *** results suggest the feasibility of enantiomeric separation of nanoparticles displaying sufficient chirality using simple silicon photonic integrated circuits,with wavelength selection based on the nanoparticle size.

关键词： dielectric forces quasi

SMILE soft X-ray Imager flight model CCD370 pre-flight device characterisation

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Earth and Planetary Physics 2024年第1期8卷 25-38页

作者： S.Parsons D.j.Hall o.Hetherington T.W.Buggey T.Arnold M.W.j.Hubbard A.Holland Centre for Electronic Imaging the Open UniversityMilton KeynesMK76AAUK

Throughout the SMILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their *** order to understand the changes of the CCD370s within the soft X-ray Imager,an initial characterisation of the devices has been carried out to give a baseline performance *** CCDs have been characterised,the two flight devices and the flight spa *** has been carried out at the open University in a bespo ke cleanroom measure ment *** results show that there is a cluster of bright pixels in the flight spa re which increases in size with tempe *** at the nominal ope rating tempe rature(-120℃) it is within the procure ment ***,the devices meet the specifications when ope rating at -120℃ in 6 × 6 binned frame transfer science *** se rial charge transfer inefficiency degrades with temperature in full frame *** any charge losses are recovered when binning/frame transfer is implemented.

关键词： CCD soft X-ray imager characterisation SMILE

Stability analysis of a time-delayed Van der Pol–Helmholtz–Duffing oscillator in fractal space with a non-perturbative approach

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Communications in Theoretical Physics 2024年第4期76卷 22-31页

作者： Yusry o El-Dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The time-delayed fractal Van der Pol–Helmholtz–Duffing(VPHD)oscillator is the subject of this paper,which explores its mechanisms and highlights its stability *** time-delayed technologies are currently garnering significant attention,the focus of this research remains crucially relevant.A non-perturbative approach is employed to refine and set the stage for the system under *** innovative methodologies introduced yield an equivalent linear differential equation,mirroring the inherent nonlinearities of the ***,the incorporation of quadratic nonlinearity into the frequency formula represents a cutting-edge *** analytical solution's validity is corroborated using a numerical *** conditions are ascertained through the residual Galerkin ***,it is observed that the delay parameter,in the context of the fractal system,reverses its stabilizing influence,impacting both the amplitude of delayed velocity and the *** analytical solution's precision is underscored by its close alignment with numerical ***,the study reveals that fractal characteristics emulate damping *** its applicability across diverse nonlinear dynamical systems,this non-perturbative approach emerges as a promising avenue for future research.

关键词： Van der Pol-Helmholtz-Duffing oscillator fractal space time-delay non-perturbative approach stability analysis El-Dib's frequency formula