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Improved Responses with Multitaper Spectral Analysis for Magnetotelluric Time Series Data processing:Examples from Field Data

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Acta Geologica Sinica(English Edition) 2024年第S01期98卷 14-17页

作者： Matthew j.COMEAU rafael RIGAUD johanna pLETT Michael BECKEN Alexey KUVSHINOV Department of Geoscience&Engineering Delft University of Technology The Netherlands Institute of Geophysics ETHZürichSwitzerland Institut für Geophysik Universität MünsterGermany

In order to attain good quality transfer function estimates from magnetotelluric field data(i.e.,smooth behavior and small uncertainties across all frequencies),we compare time series data processing with and without a multitaper approach for spectral *** are several common ways to increase the reliability of the Fourier spectral estimation from experimental(noisy)data;for example to subdivide the experimental time series into segments,taper these segments(using single taper),perform the Fourier transform of the individual segments,and average the resulting spectra.

关键词： magnetotellurics electrical resistivity time series processing Fourier analysis multitaper

Three-dimensional seismic face stability of shield tunnels inundrained clay

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Underground Space 2024年第2期15卷 26-43页

作者： Milad Davoodi Salvador Senent Amin Keshavarz rafael jimenez Civil Engineering Department School of EngineeringPersian Gulf UniversityBushehr ***Iran Universidad politecnica de Madrid C/Prof.Aranguren s/nMadrid 28040Spain

Tunnel face stability has received increasing research interest over the past few decades. However, computing time-efficient and safethree-dimensional solutions under seismic loading is still an unsolved problem, while case studies indicate that seismic loading can be onecritical destabilizing factor affecting tunnel stability. The primary objective of this work is to fill this gap in knowledge by providing compromisingand computationally efficient solutions, along with their respective lower and upper bounds, to compute face stability underseismic conditions. The analyses employ the finite element limit analysis method to evaluate the limit support pressure in undrained clay,considering horizontal pseudo-static seismic forces pointing outwards from the face. Moreover, the analyses employ both constant andlinearly increasing shear strengths with depth. The results are summarized as dimensionless stability charts and tables to facilitate theirinterpretation and future use for tunnel design. A new design equation has been developed to evaluate the stability of the tunnel faceconsidering the effect of seismic forces. Additionally, the effects of different parameters on the shape of the failure mechanism have beeninvestigated by analysing the distribution of shear dissipation.

关键词： Tunnel face stability Finite element limit analysis Undrained clay Seismic stability

Mathematical modeling for estimating influenza vaccine efficacy:A case study of the Valencian Community,Spain.

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Infectious Disease Modelling 2024年第3期9卷 744-762页

作者： Carlos Andreu-Vilarroig rafael j.Villanueva Gilberto González-parra Instituto de Matemática Multidisciplinar Universitat Politècnica de ValènciaValenciaSpain Department of Mathematics New Mexico TechSocorroNMUSA

Vaccine efficacy and its quantification is a crucial concept for the proper design of public health vaccination *** this work we proposed a mathematical model to estimate the efficacy of the influenza vaccine in a real-word *** particular,our model is a SEIR-type epidemiological model,which distinguishes vaccinated and unvaccinated ***,its dynamics is governed by a nonlinear system of ordinary differential equations,where the non-linearity arises from the effective contacts between susceptible and infected *** key aspects of this study is that we use a vaccine distribution over time that is based on real data specific to the elderly people in the Valencian Community and the calibration process takes into account that over one influenza season a specific proportion of the population becomes infected with *** consider the effectiveness of the vaccine,the model incorporates a parameter,the vaccine attenuation factor,which is related with the vaccine efficacy against the influenza *** this framework,in order to calibrate the model parameters and to obtain an influenza vaccine efficacy estimation,we considered the 2016–2017 influenza season in the Valencian Community,Spain,using the influenza reported cases of vaccinated and *** order to ensure the model identifiability,we choose to deterministically calibrate the parameters for different scenarios and we find the one with the minimum error in order to determine the vaccine *** calibration results suggest that the influenza vaccine developed for 2016–2017 influenza season has an efficacy of approximately 76.7%,and that the risk of becoming infected is five times higher for an unvaccinated individual in comparison with a vaccinated *** estimation partially agrees with some previous studies related to the influenza *** study presents a new integrated mathematical approach to study the influenza vaccine efficacy and gives f

关键词： Mathematical modeling Epidemiology SEIR Vaccine efficacy Influenza Valencian community

Lipedema:A common though often unrecognized condition

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Chinese journal of plastic and Reconstructive Surgery 2024年第3期6卷 149-153页

作者： rafael Carvalho private practice R.Iolanda del Nero Barco101PirassunungaSao Paulo13631-064Brazil

Lipedema is a chronic disorder primarily affecting women,characterized by abnormal fat deposition in the extremities,leading to pain,mobility issues,and psychological *** fat deposits are clear-cut and spare hands and *** misdiagnosed as lymphedema,its prevalence remains uncertain due to a lack of universally accepted diagnostic criteria and difficulty in differentiating it from obesity or *** factors and hormonal influences are likely related to the pathophysiology of the disease,though the specific causes remain *** techniques may aid evaluation,but no definitive test exists,and diagnosis is made *** treatments such as lifestyle modifications and compression garments are considered first-line treatments,while surgical options such as liposuction and lipectomy are reserved for severe or refractory *** support may be recommended,given lipedema’s impact on quality of life and *** review aims to present the current understanding of this condition,including challenges in diagnosis,current guideline recommendations for clinical care,and associated comorbid conditions.

关键词： Lipedema Obesity Lymphedema Liposuction Lipectomy

photoluminescent Tb^(3+)-based metal-organic framework as a sensor for detection of methanol in ethanol fuel

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journal of Rare Earths 2019年第3期37卷 225-231页

作者： Ramon R.F.Fonseca rafael D.L.Gaspar Ivo M.Raimundo jr. priscilla p.Luz Department of Chemistry Federal University of Espírito Santo Institute of Chemistry University of Campinas

The sensing capability of a Tb^(3+)-metal-organic framework, based on its photoluminescence, was used for detection of methanol in ethanol fuel. It was synthesized using terbium and trimesic acid as a metal ion center and ligand, respectively. powder X-ray diffraction, infrared spectroscopy, thermogravimetric analysis and scanning electron microscopy were employed to characterize the synthesized MOF-76 structural features. According to the results, MOF-76 was successfully obtained with minor synthetic modification and its activated form(named TbTMA) was tested as a sensor for methanol. Tb^(3+) luminescence intensity increases as the methanol concentration in ethanol fuel also increases and the water content does not affect this response. Our findings indicate TbTMA as an appropriate sensor for evaluating ethanol fuel adulteration by methanol addition above the allowed limit.

关键词： Lanthanide Metal-organic frameworks Luminescence Ethanol fuel Sensor Adulteration

Exercise-induced oxidative stress:Friend or foe?

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journal of Sport and Health Science 2020年第5期9卷 415-425页

作者： Scott K.powers rafael Deminice Mustafa Ozdemir Toshinori Yoshihara Matthew p.Bomkamp Hayden Hyatt Department of Applied physiology and Kinesiology University of FloridaGainesvilleFL32608USA Department of physical Education State University of LondrinaLondrina10011Brazil Department of Exercise and Sport Sciences Hacettepe UniversityAnkara06800Turkey Department of Exercise physiology Juntendo UniversityTokyo270-1695Japan

The first report demonstrating that prolonged endurance exercise promotes oxidative stress in humans was published more than 4 decades *** this discovery,many ensuing investigations have corroborated the fact that muscular exercise increases the production of reactive oxygen species(ROS)and results in oxidative stress in numerous tissues including blood and skeletal *** several tissues may contribute to exercise-induced ROS production,it is predicted that muscular contractions stimulate ROS production in active muscle fibers and that skeletal muscle is a primary source of ROS production during *** contraction-induced ROS generation is associated with(1)oxidant damage in several tissues(e.g.,increased protein oxidation and lipid peroxidation),(2)accelerated muscle fatigue,and(3)activation of biochemical signaling pathways that contribute to exercise-induced adaptation in the contracting muscle *** our understanding of exercise and oxidative stress has advanced rapidly during the last decades,questions remain about whether exercise-induced increases in ROS production are beneficial or harmful to *** review addresses this issue by discussing the site(s)of oxidant production during exercise and detailing the health consequences of exercise-induced ROS production.

关键词： Hormesis Oxidants Radicals Reactive oxygen species Skeletal muscle

Nylon 6-cellulose composite hosted in a hypodermic needle: Biofluid extraction and analysis by ambient mass spectrometry in a single device

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journal of pharmaceutical Analysis 2023年第11期13卷 1346-1352页

作者： jaime Millan-Santiago rafael Lucena Soledad Cardenas Affordable and Sustainable Sample preparation(AS2p)Research Group Analytical Chemistry DepartmentChemical Institute for Energy and Environment(IQUEMA)University of CordobaE-14071CordobaSpain

This study proposes a hypodermic needle(HN)as a sorbent holder and an electrospray(ESI)emitter,thus combining extraction and analysis in a single device.A novel nylon 6-cellulose(N6-Cel)composite sorbent is proposed to extract methadone from oral fluid *** cellulosic substrate provides the composite with high porosity,permitting the flow-through of the sample,while the polyamide contributes to the extraction of the *** low price of the devices(considering the holder and the sorbent)contributes to the affordability of the method,and their small size allows easy transportation,opening the door to on-site *** the optimum conditions,the analyte can be determined by high-resolution ambient ionization mass spectrometry at a limit of detection(LOD)as low as 0.3 mg/L and precision(expressed as relative standard deviation,RSD)better than 9.3%.The trueness,expressed as relative recovery(RR),ranged from 90%to 109%.As high-resolution mass spectrometers are not available in many laboratories,the method was also adapted to low-resolution *** this sense,the direct infusion of the eluates in a triple quadrupole-mass spectrometry provided an LOD of 2.2 mg/*** RSD was better than 5.3%,and the RR ranged from 96%to 121%.

关键词： ESI emitter Mass spectrometry Hypodermic needle Composite Methadone

Substituent effects on novel lanthanide(Ⅲ) hydrazides complexes

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journal of Rare Earths 2020年第6期38卷 642-648页

作者： Samira G.Brandao Marcos A.Ribeiro rafael V.perrella paulo C.de Sousa Filho priscilla p.Luz Department of Chemistry Federal University of Espirito Santo29075-910VitoriaESBrazil Institute of Chemistry University of CampinasPO Box 615413083-970CampinasSPBrazil

New lanthanide(Eu3+ and Gd3+) complexes were successfully synthesized and the effect of the p-phe nyl substituent on the Eu3+luminescent properties was *** this sense,benzhydrazide,p-toluic hydrazide,4-hydroxybenzhydrazide and 4-aminobenzoic hydrazide were used as ligands and the complexes were obtained by mixing the lanthanide salts with hydrazides in ethanol at room temperature and keeping the reaction for 2 h under mechanical *** of Gd-amino was obtained and its structure was elucidated by single-crystal X-ray diffraction,revealing that Gd3+centered in a distorted tricapped trigonal-prismatic molecular *** spectroscopy and the elucidated structure confirm hydrazides acting as bidentate ligands binding to Ln3+ions through the oxygen of carbonyl group and the nitrogen of terminal amine,forming a five-membered ring,CHN analyses confirm the molecular formulas [Gd(amino)4(H2 O)](NO3)3·(C2 H5 OH) and [Eu(toluic)3(H2 O)3](NO3)*** T1 state energies are observed for ligands p-substituted with higher electron donating capacity groups,such as p-NH2 and *** contrast,higher lifetimes and quantum efficiencies are obtained for Eu3+complexes with ligands p-H and p-CH3 substituted,which are not deactivator groups.

关键词： Lanthanide Hydrazide Substituent effect photoluminescence Europium Gadolinium

Structural Basis of Interaction of Bipartite Nuclear Localization Signal from Agrobacterium VirD2 with Rice Importin-o

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Molecular plant 2014年第6期7卷 1061-1064页

作者： Chiung-Wen Chang, Simon j. Williams, rafael Miguez Cou?ago Bostjan Kobe School of Chemistry and Molecular Biosciences Institute for Molecular Bioscience and Australian Infectious Diseases ResearchCentre University of Queensland Brisbane Qld 4072 Australia

Dear Editor, In the eukaryotic cell, the nuclear envelope separates genomic DNA from the rest of the cell, but ensures a molecu- lar communication between the nucleus and the cytoplasm through the nuclear pore complexes （NpCs）. Nuclear trans- port of macromolecules is an energy-dependent process, exemplified by the classical nuclear import pathway. In the cytoplasm, proteins containing classical nuclear localization signals （cNLSs） are recognized by a hetero-dimeric transport receptor （importin-α （Impα）：importin-β （Impl3） complex）. Impa is employed as an adaptor protein that specifically rec-ognizes the classical nuclear localization signal （cNLS） from the cargo protein （Marfori et al., 2011）. Translocation of the trimeric cargo：transport receptor import complex through the NpCs is mediated by transient interactions between Impβ and nucleoporins in the NpC. The directionality of the trans- port is imparted by the asymmetric distribution, between the cytoplasm and the nucleus, of the distinct nucleotide-bound （GTp/GDp） states of the small GTpase Ran （Tran et al., 2007）.

关键词： AGROBACTERIUM RESEARCH pLANT proteins pLANT proteins -- Structure pLANT cell nuclei CRYSTAL structure CARRIER proteins -- Molecular structure CARRIER proteins RICE -- Research