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Dynamics of 1-D Electron Motion under a Periodic Electric Field with Radiation Reaction Effect

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Journal of Applied Mathematics and Physics 2020年第5期8卷 814-820页

作者： Gustavo V. López Jorge lizarraga Departamento de Física Universidad de Guadalajara Blvd. Marcelino García Barragan y Calzada Olímpica Guadalajara Jalisco Mexico

We consider the 1-D motion of an electron under a periodic force and take into account the effect of radiation reaction dissipation force on its motion, using the formulation of novel radiation reaction force as a function of the external force expression. Two cases are considered: a simple sinusoidal time depending force, and sinusoidal electromagnetic force with position and time dependence. The purpose of the study of these cases is to bring about a way to find an experimental study to determine the validity of this novel approach for the radiation reaction force. We found that the difference of the normalized (with respect the speed of light) velocities, with and without radiation reaction, is quite small between 10-31 to 10-14 for intensities on the electric field of 10-8 to 1 Dynes/ues, which may represent some concern to measure experimentally.

关键词： Radiation Reaction Force 1-D Electron Motion Damping Motion

Urgent tracheostomy： four-year experience in a tertiary hospital

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World Journal of Emergency Medicine 2016年第3期7卷 227-230页

作者： liliana Costa Ricardo Matos Sara Julio Fernando Vales Margarida Santos Otorhinolaryngology Sao Joao Hospital Center Porto 4200-319 Portugal

BACKGROUND: Urgent airway management is one of the most important responsibilities of otolaryngologists, often requiring a multidisciplinary approach. Urgent surgical airway intervention is indicated when an acute airway obstruction occurs or there are intubation difficulties. In these situations, surgical tracheostomy becomes extremely ***: We retrospectively studied the patients who underwent surgical tracheostomy from 2011 to 2014 by an otolaryngologist team at the operating theater of the emergency department of a tertiary hospital. Indications, complications and clinical evolution of the patients were ***: The study included 56 patients(44 men and 12 women) with a median age of 55 years. The procedure was performed under local anesthesia in 21.4% of the patients. Two(3.6%) patients were subjected to conversion from cricothyrostomy to tracheostomy. Head and neck neoplasm was indicated in 44.6% of the patients, deep neck infection in 19.6%, and bilateral vocal fold paralysis in 10.7%. Stridor was the most frequent signal(51.8%). Of the 56 patients, 15 were transferred to another hospital. Among the other 41 patients, 21 were decannulated(average time: 4 months), and none of them were cancer patients. Complications occurred in 5(12.2%) patients: hemorrhage in 3, surgical wound infection in 1, and cervico-thoracic subcutaneous emphysema in 1. No death was related to the ***: Urgent tracheostomy is a life-saving procedure for patients with acute airway obstruction or with diffi cult intubation. It is a safe and effective procedure, with a low complication rate, and should be performed before the patient's clinical status turns into a surgical emergency situation.

关键词： Tracheostomy Cricothryrostomy Stridor Airway obstruction

Effects of chlorpyrifos on enzymatic systems of Cydia pomonella （Lepidoptera： Tortricidae） adults

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Insect Science 2017年第3期24卷 455-466页

作者： Laura Beatriz Parra Morales Raul Adolfo Alzogaray liliana Cichon Silvina Garrido Jimena Soleno Cristina Monica Montagna Laboratorio de Investigaciones Bioquimicas Quimicas y de Medio Ambiente Facultad de Ingenieria Universidad Nacional del ComahueBuenos Aires 1400 (Q83001BX) Neuquen Facultad de Ciencias del Ambiente y la Salud Universidad Nacional del Comahue Buenos Aires 1400 Neuquen Centro de Investigaciones de Plagas e Insecticidas (CIPEIN-UNIDEFICONICET) Villa Martelli Buenos Aires Instituto de Investigacion e Ingenieria Ambiental (3iA-UNSAM) San Martin Provincia de Buenos Aires Instituto Nacional de Tecnologia Agropecuaria Estacion Experimental Alto Valle General Roca Argentina

The control program of codling moth （Cydia pomonella L.） in the Rio Negro and Neuqu6n Valley is intended to neonate larvae. However, adults may be subjected to sublethal pesticide concentrations generating stress which might enhance both mutation rates and activity of the detoxification system. This study assessed the exposure effects of chlorpyrifos on target enzyme and, both detoxifying and antioxidant systems of surviving adults from both a laboratory susceptible strain （LSS） and a field population （FP）. The results showed that the FP was as susceptible to chlorpyrifos as the LSS and, both exhibited a similar chlorpyrifos-inhibitory concentration 50 （IC50） of acetylcholinesterase （ACHE）. The FP displayed higher carboxylesterase （CarE） and 7-ethoxycoumarine O-deethylase （ECOD） activities than LSS. Both LSS and FP showed an increase on CarE activity after the exposure to low-chlorpyrifos concentrations, followed by enzyme inhibition at higher concentrations. There were no significant differences neither in the activities of glutathione S-transferases （GST）, catalase （CAT） and superoxide dismutase （SOD） nor in the reduced glutathione （GSH） content between LSS and FP. Moreover, these enzymes were unaffected by chlorpyrifos. In conclusion, control adults from the FP exhibited higher CarE and ECOD activities than control adults from the LSS. AChE and CarE activities were the most affected by chlorpyrifos. Control strategies used for C. pomonella, such as rotations of insecticides with different modes of action, will probably delay the evolution of insecticide resistance in FPs from the study area.

关键词： acetylcholinesterase antioxidant system chlorpyrifos codling moth detoxification enzymes

Pressurized Liquid Extraction of Pigments from Chlamydomonas *** Chemical Characterization by HPLC–MS/MS

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Journal of Analysis and Testing 2018年第2期2卷 149-157页

作者： Lidia Montero Mahshid Sedghi Yolanda García Carlos Almeida Carl Safi Nicole Engelen‑Smit Alejandro Cifuentes Jose A.mendiola Elena Ibáñez Applied Analytical Chemistry University of Duisburg-EssenUniversitaetsstr.545141 EssenGermany Laboratory of Foodomics Bioactivity and Food Analysis DepartmentInstitute of Food Science Research CIAL(CSIC-UAM)Campus de CantoblancoC/Nicolás Cabrera 928049 MadridSpain Spanish Bank of Algae Instituto de Oceanografía y Cambio GlobalFundación Canaria Parque Científico‑TecnológicoUniversidad de Las Palmas de Gran CanariaMuelle de Taliarte s/n35214 Telde(Canary Islands)Spain Wageningen Food and Biobased Research Wageningen University and ResearchPO Box 176700 AA WageningenThe Netherlands

Pressurized liquid extraction using green solvents(ethanol and water)was applied to extract photosynthetic pigments from the microalgae Chlamydomonas *** experimental design is employed to determine the effect of the extraction conditions on the extraction yield and the antioxidant capacity of the different extracts determined using 1,1-diphenyl-2-picryl-hydrazyl and TEAC *** the extracts show significant antioxidant activity in all ***,in this work,the carotenoid and chlorophyll composition of the Chlamydomonas extracts was analyzed by HPLC–DAD–APCI–MS/MS for the first time,being the main compounds lutein and pheophythin a′.

关键词： Antioxidant capacity Chlamydomonas sp. HPLC–DAD–APCI–MS/MS Pigments Pressurized liquid extraction Carotenoids

Experimental test of a building thermal system for preventive maintenance based on thermoeconomic analysis

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Energy Storage and Saving 2024年第1期3卷 42-51页

作者： I.Prol-Godoy A.Picallo-Perez J.M.Sala-lizarraga J.Rey-Martínez Research group ENEDI Department of Thermal EngineeringUniversity of the Basque Country(UPV/EHU)Bilbao48013Spain Research Group Termotecnia University of ValladolidValladolid47002Spain

An analysis of the sectorial structure of energy consumption shows that residential and tertiary sector buildings are the third-highest consumers,responsible for 29.5%of a city’s final energy *** Building Quality Control Laboratory of the Basque Government aims to promote quality,innovation,and sustainability in *** accomplish this goal,it has constructed an experimental facility with different energy generation technologies and a very versatile control system for testing different energy systems and operation *** this study,we tested a facility for supplying domestic hot water and heating for a multi-family house by means of a condensing boiler and an aerothermal heat pump(together with the corresponding control).This installation could reproduce the thermal demands required to be satisfied by the generation equipment through a programmed operation of the installation based on real ***,this installation was analyzed using thermoeconomics(TE)to solve problems unable to be solved using traditional energy analyses based on the First Law of *** problems include:(1)Determining the costs of the products of the installation based on physical criteria,(2)detecting the places where losses actually occur,evaluating their costs,and proposing cost-effective improvements,and(3)diagnosing issues in the *** a result,this paper suggests a solution to the preventive maintenance problems confronting the technical maintenance personnel for thermal installations in buildings by applying TE knowledge and using real data collected from sensors.

关键词： Experimental essay Energy savings in thermal systems Thermoeconomics Thermoeconomic costs Diagnosis

Risk of venous thromboembolic disease in postmenopausal women taking oral or transdermal hormone replacement therapy

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第1期12卷 12-17页

作者： Barbara RUSZKOWSKA GraZyna GADOMSKA liliana BIELIS Marzena GRUSZKA Barbara GóRALCZYK Danuta RO GraZyna ODROWAZ-SYPNIEWSKA Department of Pathophysiology Collegium Medicum in BydgoszczNicolaus Copernicus University in Toruń Department of Laboratory Medicine Collegium Medicum in BydgoszczNicolaus Copernicus University in Toruń Department of Laboratory Medicine Collegium Medicum in BydgoszczNicolaus Copernicus University in Toruń

Objective: The influence of hormone replacement therapy (HRT) on hemostasis processes depends on the type of hormone,the combination of doses,the time of taking HRT,and the route of administration (oral,transdermal,implanted).The aim of the current study was to assess some parameters of coagulation,especially tissue factor pathway inhibitor (TFPI) and tissue factor (TF) in postmenopausal women using oral or transdermal ***: The study was conducted on 76 healthy women,including 46 women aged 44–58 years who were taking oral (26) or transdermal (20) HRT,and 30 women aged 44–54 years who did not take HRT as the control *** concentrations of TF,TFPI,thrombin-antithrombin complex (TAT),and D-dimer were performed by enzyme-linked immunosorbent assay (ELISA).Moreover,the concentration of fibrinogen and activity of protein C were measured by chromogenic and chronometric ***: We observed a significantly higher concentration of TF and a significantly lower concentration of TFPI in women taking oral and transdermal HRT in comparison with the control *** also found a significantly lower concentration of fibrinogen in women taking oral HRT *** control ***,no statistically significant changes in concentrations of TAT and D-dimer,or activity of protein C were ***: In this study,the occurrence of an increased TF concentration simultaneously with a decreased concentration of TFPI in women taking HRT indicates *** significant modification of TAT or D-dimer occurred,and thus there may not be increased risk of thrombosis.

关键词： Menopause Coagulation Hormone replacement therapy

Does board gender diversity affect firm performance?Empirical evidence from Standard & Poor’s 500 Information Technology Sector

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Financial Innovation 2021年第1期7卷 1124-1168页

作者： liliana Nicoleta Simionescu Ştefan Cristian Gherghina Hiba Tawil Ziad Sheikha Department of Finance Bucharest University of Economic Studies6 Romana Square010374 BucharestRomania

The essence of this study is to investigate the influence of the board gender diversity on firms’accounting and market-based performance using a sample of Standard&Poor’s 500 companies belonging to the information technology sector over 12 *** the pooled ordinary least squares(OLS)method,the outcomes provide evidence for a positive influence of women on corporate boards on both measures of company performance,except for the percentage of female executives in the case of return on assets(ROA).After estimating the fixed effects and random-effects through panel data,the econometric outcomes show no statistically significant association among board gender diversity and ROA but a positive influence of the number and percentage of women on board on price-to-earnings ratio.

关键词： Gender diversity Firm performance Pooled OLS Fixed-effects Randomeffects

Single Charged Particle Motion in a Flat Surface with Static Electromagnetic Field and Quantum Hall Effect

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Journal of Modern Physics 2022年第11期13卷 1324-1330页

作者： Gustavo V. López Jorge A. lizarraga Departamento de Física Universidad de Guadalajara Guadalajara México

Taking into account the non separable solution for the quantum problem of the motion of a charged particle in a flat surface of lengths Lx and Ly with transversal static magnetic field B and longitudinal static electric field E, the quantum current, the transverse (Hall) and longitudinal resistivities are calculated for the state n = 0 and j = 0. We found that the transverse resistivity is proportional to an integer number, due to the quantization of the magnetic flux, and longitudinal resistivity can be zero for times t >> LxB/cE. In addition, using a modified periodicity of the solution, a modified quantization of the magnetic flux is found which allows to have IQHE and FQHE of any filling factor of the form v = k/l, with k, l ∈Z.

关键词： Landau’s Gauge Quantum Hall Effect Degeneration

Fractal Fractional Order Operators in Computational Techniques for Mathematical Models in Epidemiology

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1385-1403页

作者： Muhammad Farman Ali Akgül Mir Sajjad Hashemi liliana Guran Amelia Bucur Institue of Mathematics Khwaja Fareed University of Enginnering and Information TechnologyRaheem Yar KhanPakistan Department of Computer Science and Mathematics Lebanese American UniversityBeirutLebanon Department of Mathematics Art and Science FacultySiirt UniversitySiirt56100Turkey Department of Mathematics Mathematics Research CenterNear East UniversityNicosiaTurkey Department of Computer Engineering Biruni UniversityIstanbul34010Turkey Department of Hospitality Services Babes-Bolyai UniversityCluj-Napoca400174Romania Department of Pharmaceutical Sciences Vasile Goldi竤Western University of AradArad310025Romania Department of Mathematics and Informatics Faculty of SciencesLucian Blaga University of SibiuSibiu550012Romania Department of Electronics and Communication Engineering Saveetha School of EngineeringSIMATSChennaiTamilnaduIndia

New fractional operators, the COVID-19 model has been studied in this paper. By using different numericaltechniques and the time fractional parameters, the mechanical characteristics of the fractional order model areidentified. The uniqueness and existence have been established. Themodel’sUlam-Hyers stability analysis has beenfound. In order to justify the theoretical results, numerical simulations are carried out for the presented methodin the range of fractional order to show the implications of fractional and fractal *** applied very effectivenumerical techniques to obtain the solutions of themodel and simulations. Also, we present conditions of existencefor a solution to the proposed epidemicmodel and to calculate the reproduction number in certain state conditionsof the analyzed dynamic system. COVID-19 fractional order model for the case of Wuhan, China, is offered foranalysis with simulations in order to determine the possible efficacy of Coronavirus disease transmission in theCommunity. For this reason, we employed the COVID-19 fractal fractional derivative model in the example ofWuhan, China, with the given beginning conditions. In conclusion, again the mathematical models with fractionaloperators can facilitate the improvement of decision-making for measures to be taken in the management of anepidemic situation.

关键词： COVID-19 model fractal-fractional operator Ulam-Hyers stability existence and uniqueness numerical simulation