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Output feedback adaptive super twisting sliding mode control for quadrotor UAVs

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Control Theory and Technology 2024年第1期22卷 92-105页

作者： Oscar Salas-Peña Jesus DeLeón-Morales Susana V.gutiérrez-Martínez École Centrale de Nantes-LS2N UMR 6004 CNRS44300NantesFrance Facultad de Ingeniería Mecánica y Eléctrica Universidad Autónoma de Nuevo León66451San Nicolás de Los GarzaMexico

In this paper, a sliding mode control with adaptive gain combined with a high-order sliding mode observer to solve the tracking problem for a quadrotor UAV is addressed, in presence of bounded external disturbances and parametric uncertainties. The high order sliding mode observer is designed for estimating the linear and angular speed in order to implement the proposed scheme. Furthermore, a Lyapunov function is introduced to design the controller with the adaptation law, whereas an analysis of finite time convergence towards to zero is provided, where sufficient conditions are obtained. Regarding previous works from literature, one important advantage of proposed strategy is that the gains of control are parameterized in terms of only one adaptive parameter, which reduces the control effort by avoiding gain overestimation. Numerical simulations for tracking control of the quadrotor are given to show the performance of proposed adaptive control–observer scheme.

关键词： Adaptive super twisting controller High-order sliding modes observer UAV

Stress tensors and quantification of fracture patterns to analyze connectivity and potential fluid flow in a mesa landform of the Northern Andes

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Journal of Mountain Science 2024年第1期21卷 271-291页

作者： GARCÍA-ARIAS Sergio VELANDIA Francisco ALVAREZ angélica SANABRIA-GÓMEZ JoséD TARAZONA Yessenia VARGAS María Camila Escuela de Geología Universidad Industrial de SantanderCra.27 Calle 9BucaramangaColombia Escuela de Física Universidad Industrial de SantanderCra.27 Calle 9BucaramangaColombia

This work applies stress tensors inversions and quantification of fracture patterns along the Mesa de Los Santos, in the Eastern Cordillera of Colombia, to better understand the potential fluid flow. It thus contributes to the conceptual hydrogeological model. The area was subdivided into three blocks, separated by the NW Potreros and the Los Santos faults, having minor inner faults of different orientations. This separation facilitates the analysis of the fractures measured in the field, which in general show high dip angles and a conjugate geometry in the northern block, tension fractures(Mode I) in the central block, and a random distribution in the southwestern block. WinTensor treatment of slickensides yielded a maximum horizontal stress(SHmax) of 111o, which coincides with the WNW-ESE tensor observed from the conjugate and tension joints. We then used Frac Pa Q to generate interpolation maps of fracture intensity and density. The maps show the highest values in the central block and the lowest in the northern block,where the precipitation is higher, causing intensive rock weathering and homogenization of the fracture planes. Although the highest values of connectivity by line are found to the south of the mesa, we suggest the possibility of greater flow from the recharge zone(NE) along bedding planes and open NW-SE fractures.

关键词： Mesa de Los Santos Colombia Win-Tensor FracPaQ Strike-slip faults Fractured aquifers

Metabolomics for the diagnosis of bladder cancer: A systematic review

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Asian Journal of Urology 2024年第2期11卷 221-241页

作者： Herney Andrés García-Perdomo angélica María Dávila-Raigoza Fernando Korkes Division of Urology/Urooncology Department of SurgerySchool of MedicineUniversidad del ValleCaliColombia UROGIV Research Group School of MedicineUniversidad del ValleCaliColombia Urologic Oncology Division of UrologyABC Medical SchoolSao PauloBrazil

Objective: Metabolomics has been extensively utilized in bladder cancer (BCa) research, employing mass spectrometry and nuclear magnetic resonance spectroscopy to compare various variables (tissues, serum, blood, and urine). This study aimed to identify potential biomarkers for early BCa ***: A search strategy was designed to identify clinical trials, descriptive and analytical observational studies from databases such as Medline, Embase, Cochrane Central Register of Controlled Trials, and Latin American and Caribbean Literature in Health Sciences. Inclusion criteria comprised studies involving BCa tissue, serum, blood, or urine profiling using widely adopted metabolomics techniques like mass spectrometry and nuclear magnetic resonance. Primary outcomes included description of metabolites and metabolomics profiling in BCa patients and the association of metabolites and metabolomics profiling with BCa diagnosis compared to control patients. The risk of bias was assessed using the Quality Assessment of Studies of Diagnostic ***: The search strategy yielded 2832 studies, of which 30 case-control studies were included. Urine was predominantly used as the primary sample for metabolite identification. Risk of bias was often unclear inpatient selection, blinding of the index test, and reference standard assessment, but no applicability concerns were observed. Metabolites and metabolomics profiles associated with BCa diagnosis were identified in glucose, amino acids, nucleotides, lipids, and aldehydes ***: The identified metabolites in urine included citric acid, valine, tryptophan, taurine, aspartic acid, uridine, ribose, phosphocholine, and carnitine. Tissue samples exhibited elevated levels of lactic acid, amino acids, and lipids. Consistent findings across tissue, urine, and serum samples revealed downregulation of citric acid and upregulation of lactic acid, valine, tryptophan, taurine, glutamine, aspartic acid, uridine, rib

关键词： Metabolite Metabolomics Bladder cancer Metabolomicsprofile

Roller Screw and Threaded Chain Speed Reducer: An Experimental Evaluation

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Modern Mechanical Engineering 2024年第1期14卷 1-11页

作者： Filiberto gutiérrez Instituto de Ingeniería Universidad Nacional Autónoma de México Mexico City Mexico

We are developing a speed reducer that can be considered a transformation of a worm gear reducer: the worm is replaced by an inverted roller screw, and the gear is replaced by a threaded chain drive. This configuration lessens wear, increases load capacity, and improves efficiency. The threaded chain consists of nut-shaped links. This paper presents the results of tests carried out on a prototype with a reduction ratio of 46.

关键词： Speed Reducer Inverted Roller Screw Chain Drive Threaded Chain Drive

THE SUMERIAN TERM u_(8)/ud_(5)/ab_(2)/eme_(3)/_(6)sila_(4)/maš_(2)/amar du_(3)(-a)

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Journal of Ancient Civilizations 2024年第1期39卷 1-28,123页

作者： Marcos Such-gutiérrez Facultad de Filosofía y Letras Universidad Autónoma de Madrid

The aim of the present article is twofold:firstly,to prove that the expression animal+young du_(3)(-a),which is basically documented in texts from the 3rd millennium BC,refers to a dam that has just given birth,and se... 详细信息

关键词： 3rd millennium BC female animal+young du_(3)(-a) livestock newborn suckling animal UrⅢperiod

Latest developments in early diagnosis and specific treatment of severe influenza infection

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Journal of Intensive Medicine 2024年第2期4卷 160-174页

作者： Francisco Valenzuela-Sánchez Blanca Valenzuela-Méndez Juan Francisco Rodríguez-gutiérrez Ángel Estella Intensive Care Unit University Hospital of JerezRonda de Circunvalación s/nJerez de la FronteraSpain Haematology Department University Hospital of JerezRonda de Circunvalación s/nJerez de la FronteraSpain Centro de Investigación Biomédica en Red Enfermedades respiratoriasCIBERESInstituto de Salud Carlos IIIAv.de Monforte de LemosMadridSpain Department of Oncological Surgery Institut du Cancer de Montpellier(ICM)Parc Euromédecine208 Av.des ApothicairesMontpellierFrance Department of Medicine Faculty of MedicineUniversity of CádizCalle Doctor MarañónCádizSpain Instituto de Investigación e Innovación Biomédica de Cádiz(INIBiCA) Avenida Ana de Viya 21CádizSpain

Influenza pandemics are unpredictable recurrent events with global health,economic,and social *** objective of this review is to provide an update on the latest developments in early diagnosis and specific treatment of the disease and its complications,particularly with regard to respiratory organ *** advances in treatment,the rate of mortality in the intensive care unit remains approximately 30%.Therefore,early identification of potentially severe viral pneumonia is extremely important to optimize treatment in these *** pathogenesis of influenza virus infection depends on viral virulence and host ***,in some patients,it is associated with an excessive systemic response mediated by an authentic cytokine *** process leads to severe primary pneumonia and acute respiratory distress *** prognostication in the emergency department based on comorbidities,vital signs,and biomarkers(e.g.,procalcitonin,ferritin,human leukocyte antigen-DR,mid-regional proadrenomedullin,and lactate)is *** of these biomarkers on admission may facilitate clinical decision-making to determine early admission to the hospital or the intensive care *** decisions are reached considering pathophysiological circumstances that are associated with a poor prognosis(e.g.,bacterial co-infection,hyperinflammation,immune paralysis,severe endothelial damage,organ dysfunction,and septic shock).Moreover,early implementation is important to increase treatment *** on a limited level of evidence,all current guidelines recommend using oseltamivir in this *** possibility of drug resistance should also be *** options include other antiviral drugs and combination therapies with monoclonal ***,it is not recommended to use corticosteroids in the initial treatment of these ***,the implementation of supportive measures for respiratory failure is ***

关键词： Influenza Pandemic Respiratory failure Acute respiratory distress syndrome Intensive care unit admission

Metal-modulated epitaxy of Mg-doped Al_(0.80)In_(0.20)N-based layer for application as the electron blocking layer in deep ultraviolet light-emitting diodes

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Journal of Semiconductors 2024年第5期45卷 80-89页

作者： Horacio Irán Solís-Cisneros Carlos Alberto Hernández-gutiérrez Enrique Campos-González Máximo López-López Optomechatronics Group Tecnológico Nacional de México Campus Tuxtla Gutiérrezcarretera Panamericana 1080C.P.29050Tuxtla GutiérrezChiapasMéxico Departamento de Física Instituto Nacional de Investigaciones NuclearesCarretera México-Toluca s/nC.P.52750La Marquesa OcoyoacacMéxico Departamento de Física Centro de Investigación y estudios Avanzados del Instituto Politécnico NacionalAv.Instituto Politécnico Nacional 2508San Pedro ZacatencoGustavo A.Madero07360 Ciudad de MéxicoCDMXMéxico

This work reports the growth and characterization of p-AlInN layers doped with Mg by plasma-assisted molecular beam epitaxy(PAMBE).AlInN was grown with an Al molar fraction of 0.80 by metal-modulated epitaxy(MME)with a thickness of 180 nm on Si(111)substrates using AlN as buffer *** substrate temperatures were used to enhance the incorporation of indium atoms into the alloy without clustering,as confirmed by X-ray diffraction(XRD).Cathodoluminescence measurements revealed ultraviolet(UV)range ***,Hall effect measurements indicated a maximum hole mobility of 146 cm^(2)/(V∙s),corresponding to a free hole concentration of 1.23×10^(19)cm^(−3).The samples were analyzed by X-ray photoelectron spectroscopy(XPS)estimating the alloy composition and extracting the Fermi level by valence band ***-doped AlInN layers were studied for use as the electron-blocking layer(EBL)in LED *** varied the Al composition in the EBL from 0.84 to 0.96 molar fraction to assess its theoretical effects on electroluminescence,carrier concentration,and electric field,using SILVACO *** results from this study highlight the importance and capability of producing high-quality Mg-doped p-AlInN layers through *** simulations suggest that an Al content of 0.86 is optimal for achieving desired outcomes in electroluminescence,carrier concentration,and electric field.

关键词： metal-modulated epitaxy AlInN DUV-LED EBL simulation

A multi-platform analysis of human gingival crevicular fluid reveals ferroptosis as a relevant regulated cell death mechanism during the clinical progression of periodontitis

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International Journal of Oral Science 2024年第2期16卷 265-279页

作者： Alfredo Torres M.angélica Michea Ákos Végvári Marion Arce Valentina Pérez Marcela Alcota Alicia Morales Rolando Vernal Mauricio Budini Roman A.Zubarev Fermín E.González Laboratory of Experimental Immunology&Cancer Faculty of DentistryUniversity of ChileSantiagoChile Department of Conservative Dentistry Faculty of DentistryUniversity of ChileSantiagoChile Division of Chemistry I Department of Medical Biochemistry and BiophysicsKarolinska InstitutetStockholmSweden Periodontal Biology Laboratory Faculty of DentistryUniversidad de ChileSantiagoChile Laboratory of Cellular and Molecular Pathology Institute for Research in Dental SciencesFaculty of DentistryUniversity of ChileSantiagoChile

Ferroptosis is implicated in the pathogenesis of numerous chronic-inflammatory diseases,yet its association with progressive periodontitis remains *** investigate the involvement and significance of ferroptosis in periodontitis progression,we assessed sixteen periodontitis-diagnosed *** progression was clinically monitored over twelve weeks via weekly clinical evaluations and gingival crevicular fluid(GCF)collection was performed for further *** metrics,proteomic data,in silico methods,and bioinformatics tools were combined to identify protein profiles linked to periodontitis progression and to explore their potential connection with *** western blot analyses validated key ***,a single-cell RNA sequencing(scRNA-seq)dataset(GSE164241)for gingival tissues was analyzed to elucidate cellular dynamics during periodontitis *** progression was identified as occurring at a faster rate than traditionally *** samples from progressing and non-progressing periodontal sites showed quantitative and qualitatively distinct proteomic *** addition,specific biological processes and molecular functions during progressive periodontitis were revealed and a set of hub proteins,including SNCA,CA1,HBB,SLC4A1,and ANK1 was strongly associated with the clinical progression status of ***,we found specific proteins-drivers or suppressors-associated with ferroptosis(SNCA,FTH1,HSPB1,CD44,and GCLC),revealing the co-occurrence of this specific type of regulated cell death during the clinical progression of ***,the integration of quantitative proteomic data with scRNA-seq analysis suggested the susceptibility of fibroblasts to *** analyses reveal proteins and processes linked to ferroptosis for the first time in periodontal patients,which offer new insights into the molecular mechanisms of progressive periodontal *** findings may le

关键词： finding progression faster

A Probabilistic Description of the Impact of Vaccine-Induced Immunity in the Dynamics of COVID-19 Transmission

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Open Journal of Modelling and Simulation 2024年第2期12卷 59-73页

作者： Javier Blecua Juan Fernández-Recio José Manuel gutiérrez Instituto de Ciencias de la Vid y del Vino (ICVV) CSIC-Universidad de La Rioja-Gobierno de La Rioja Logro&#241o Spain Departamento de Matemá ticas y Computaci&#243n Universidad de La Rioja Logro&#241o Spain

The recent outbreak of COVID-19 has caused millions of deaths worldwide and a huge societal and economic impact in virtually all countries. A large variety of mathematical models to describe the dynamics of COVID-19 transmission have been reported. Among them, Bayesian probabilistic models of COVID-19 transmission dynamics have been very efficient in the interpretation of early data from the beginning of the pandemic, helping to estimate the impact of non-pharmacological measures in each country, and forecasting the evolution of the pandemic in different potential scenarios. These models use probability distribution curves to describe key dynamic aspects of the transmission, like the probability for every infected person of infecting other individuals, dying or recovering, with parameters obtained from experimental epidemiological data. However, the impact of vaccine-induced immunity, which has been key for controlling the public health emergency caused by the pandemic, has been more challenging to describe in these models, due to the complexity of experimental data. Here we report different probability distribution curves to model the acquisition and decay of immunity after vaccination. We discuss the mathematical background and how these models can be integrated in existing Bayesian probabilistic models to provide a good estimation of the dynamics of COVID-19 transmission during the entire pandemic period.

关键词： COVID-19 Transmission Dynamics Probabilistic Model Bayesian Analysis Markov Chain Monte Carlo