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Noether conserved quantities and Lie point symmetries of difference Lagrange-maxwell equations and lattices

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Chinese Physics B 2009年第7期18卷 2634-2641页

作者：傅景礼聂宁明黄健飞 Jiménez Salvador 唐贻发 vzquez Luis 赵维加 institute of mathematical Physics Zhejiang Sci-Tech University State Key Laboratory of Scientific and Engineering Computing ICMSECAcademy of Mathematics and Systems ScienceChinese Academy of Sciences Department of mathematics Qingdao University Departamento de matema'tica Aplicada TTii E.T.S.I.Telecomunicacio'nUniversidad Polit'ecnica de Madrid28040-MadridSpain Departamento de matemática Aplicada Facultad de MatemáticasInstituto de Matemática Interdisciplinar(IMI)Universidad Complutense de Madrid28040-MadridSpain Departamento de matemática Aplicada Facultad de InformáticaInstituto de Matemática Interdisciplinar(IMI)Universidad Complutense de Madrid28040-MadridSpain

This paper presents a method to find Noether-type conserved quantities and Lie point symmetries for discrete mechanico-electrical dynamical systems,which leave invuriant the set of solutions of the corresponding difference scheme. This approach makes it possible to devise techniques for solving the Lagrange maxwell equations in differences which correspond to mechanico-electrical systems,by adapting existing differential *** particular,it obtains a new systematic method to determine both the one-parameter Lie groups and the discrete Noether conserved quantities of Lie point symmetries for mechanico-electrical *** an application,it obtains the Lie point symmetries and the conserved quantities for the difference equation of a model that represents a capacitor microphone.

关键词： Lagrange maxwell equation Lie point symmetry discrete mechanico-electrical system conserved quantity

Alterations in blink and masseter reflex latencies in older adults with neurocognitive disorder and/or diabetes mellitus

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World Journal of Clinical Cases 2022年第1期10卷 177-188页

作者： Jaime Alberto Bricio-Barrios Eder Ríos-Bracamontes mónica Ríos-Silva miguel Huerta Walter Serrano-moreno JoséEnrique Barrios-Navarro Genaro Gabriel Ortiz miguel Huerta-Trujillo JoséGuzmán-Esquivel Xóchitl Trujillo Faculty of medicine University of ColimaColima 28040ColimaMexico General Hospital Zone#1 Mexican Social Security InstituteVilla de Alvarez 28983ColimaMexico University Biomedical Research Center University of ColimaColima 28045ColimaMexico University Biomedical Research Center CONACYTColima 28045ColimaMexico Department of Philosophical and methodological Disciplines University Health Sciences CenterUniversity of GuadalajaraGuadalajara 44340JaliscoMexico

BACKGROUND Blink and masseter reflexes provide reliable,quantifiable data on the function of the central nervous system:Delayed latencies have been found in patients with neurocognitive disorder(ND)and type 2 diabetes mellitus(T2Dm),but this has not been studied in patients with both *** To investigate if older adults with ND plus T2Dm have prolonged latencies of blink and masseter-reflex and if they were associated with disease *** This cross-sectional study included 227 older adults(>60 years)from Colima,*** disorder was identified by a neuropsychological battery test,and T2Dm identified by medical history,fasting glucose,and glycosylated *** in the early reflex(R1),ipsilateral late(R2),and contralateral late(R2c)components of the blink reflex were analyzed for all subjects,and 183 subjects were analyzed for latency of the masseter *** in 20.7%of participants,ND was *** 37%,T2Dm was *** in R1,R2,and R2c were significantly prolonged for groups with ND plus T2Dm,ND,and T2Dm,compared with the control group(Pmasseter reflex was only prolonged in older adults(regardless of T2Dm status)with ND vs controls(P=0.030).in older adults with ND and without T2Dm,the more the cognitive impairment progressed,the more prolonged latencies in R2 and R2c presented(PiON These findings suggest that blink and masseter reflexes could be used to evaluate possible changes in brainstem circuits in older adults with ND and T2Dm.

关键词： Blink reflex masseter reflex Brainstem reflexes Neurocognitive disorder Type 2 diabetes mellitus Older adults

Numerical investigation of full scale coaxial main rotor aerodynamics in hover and vertical descent

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Chinese Journal of Aeronautics 2021年第5期34卷 666-683页

作者： Pavel v.mAKEEv Yuri m.iGNATKiN Alexander i.SHOmOv Department of Helicopter Design Moscow Aviation Institute(National Research University)Moscow 125993Russia

The original free vortex wake model was used for numerical *** of the aerodynamic characteristics in hover and vertical descent modes in the range of vertical descent speed of 0–30 m/s including the vortex Ring State(vRS)area was *** calculations were carried out under the condition of variable blade pitch angle values providing a fixed timeaverage thrust *** data of free vortex wake shapes,flow structures,and velocity fields were obtained and *** time-dependences of the rotor’s thrust and torque coefficients were obtained and *** obtained data allows determining the boundaries of the vRS area by various criteria such as rotor thrust and torque pulsations,growth of rotor power consumption relative to the hover,growth of rotor induced velocities relative to the hover,and growth of the required rotor blade pitch angles *** results of the study are compared with experimental and calculated data of other authors and can significantly supplement the available results of experimental and computational studies in this area.

关键词： Aerodynamic characteristics Coaxial rotor Free wake model Hover and vertical descent vortex ring state mode

Synthesis and applications of lanthanoid complexes of pentadentate and hexadentate N_(5) and N_(6) macrocycles:A review

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Journal of Rare Earths 2024年第1期42卷 1-15,I0001页

作者： Julio Corredoira-vázquez Cristina González-Barreira Paula Oreiro-martínez Ana m.García-Deibe Jesús Sanmartín-matalobos matilde Fondo Departamento de Química inorganica Facultade de QuímicaUniversidade de Santiago de CompostelaCampus Vida15782Santiago de CompostelaSpain Phantom-g CICECO-Aveiro Institute of MaterialsDepartment of PhysicsUniversity of Aveiro3810-193AveiroPortugal institute of materials(imATUS) Universidade de Santiago de Compostela15782Santiago de CompostelaSpain

in this paper,the lanthanoid complexes of N_(5) and N_(6) macrocycle ligands,without pendant arms or additional heteroatoms,are *** review covers the period from 2015 to the current date,since in 2014 Schiff base macrocyclic ligands incorporating the pyridine moiety,and their complexes,were revised,and in 2015 the chemistry of pentaaza macrocycle ligands with rare earth metals was also *** and phthalocyanine ligands are not included in this review,which primarily focuses on complexes with Schiff bases and amines without pendant arms or any additional donor other than *** synthetic methods,structural characterization,based on single X-ray crystal data,and properties of the lanthanoid complexes,with special attention to magneto-structural correlations,are presented herein.

关键词： Lanthanoid N_(5),N_(6)macrocycle Coordination chemistry Chirality Biological activity molecule magnet

Direct-fed microbes: A tool for improving the utilization of low quality roughages in ruminants

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Journal of integrative Agriculture 2015年第3期14卷 526-533页

作者： mona m Y Elghandour Abdelfattah Z m Salem Jose S martínez Castaeda Luis m Camacho Ahmed E Kholif Juan C vázquez Chagoyán Faculty of veterinary medicine and Animal Science Autonomous University of the State of Mexico Faculty of veterinary medicine and Animal Science Autonomous University of Guerrero Dairy Science Department National Research Centre

For many years, ruminant nutritionists and microbiologists have been interested in manipulating the microbial ecosystem of the rumen to improve production efficiency of different ruminant species. Removal and restriction of antibiotics subtherapeutic uses from ruminant diets has amplified interest in improving nutrient utilization and animal performance and search for more safe alternatives. Some bacterial and fungal microorganisms as a direct-fed microbial（DFm） can be the most suitable solutions. microorganisms that are commonly used in DFm for ruminants may be classified mainly as lactic acid producing bacteria（LAB）, lactic acid utilizing bacteria（LUB）, or other microorganism＇s species like Lactobacillus, Bifidobacterium, Enterococcus, Streptococcus, Bacillus, Propionibacterium, megasphaera elsdenii and Prevotellabryantii, in addition to some fungal species of yeast such as Saccharomyces and Aspergillus. A definitive mode of action for bacterial or fungal DFm has not been established; although a variety of mechanisms have been suggested. Bacterial DFm potentially moderate rumen conditions, and improve weight gain and feed efficiency. Fungal DFm may reduce harmful oxygen from the rumen, prevent excess lactate production, increase feed digestibility, and alter rumen fermentation patterns. DFm may also compete with and inhibit the growth of pathogens, immune system modulation, and modulate microbial balance in the gastrointestinal tract. improved dry matter intake, milk yield, fat corrected milk yield and milk fat content were obtained with DFm administration. However, the response to DFm is not constant; depending on dosages, feeding times and frequencies, and strains of DFm. Nonetheless, recent studies have supported the positive effects of DFm on ruminant performance.

关键词： direct-fed microbial(DFm) mode of action ruminants

Effect of Ta_(2)O_(5)nanoparticles on bioactivity,composition,structure,in vitro and in vivo behavior of PEO coatings on mg-alloy

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Journal of magnesium and Alloys 2024年第6期12卷 2360-2379页

作者： D.v.mashtalyar i.m.imshinetskiy v.v.Kashepa K.v.Nadaraia m.A.Piatkova A.i.Pleshkova K.A.Fomenko A.Yu.Ustinov S.L.Sinebryukhov S.v.Gnedenkov institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok690022Russia Far Eastern Federal University Vladivostok690950Russia Regional Clinical Dermatovenerological Dispensary Vladivostok690033Russia

The present study investigates the physical and chemical characteristics,behavior in vitro and in vivo,and biocompatibility of coatings containing Ta_(2)O_(5),which are obtained by plasma electrolytic oxidation(PEO)on mA8 magnesium *** obtained coatings demonstrate in vivo biocompatibility and in vitro *** to the base PEO coating,the layers containing Ta_(2)O_(5)facilitate the development of apatite in simulated body fluid,suggesting that the inclusion of nanoparticles improves bioactivity of the *** was found that incorporation of Ta_(2)O_(5)nanoparticles increases roughness and porosity of the formed layers by increasing particle concentration in electrolytes for the PEO process contributing to sufficient soft tissue ingrowth in *** on in vivo studies,these coatings also provide favorable tissue response and minimal inflammatory reaction in comparison with the bare magnesium alloy due to protection of living tissues from deleterious corrosion events of magnesium implant such as local alkalization and intense hydrogen *** results obtained in the present study concluded biocompatibility,tissue integration of the PEO coatings containing Ta_(2)O_(5)nanoparticles making them a promising protective layer for biodegradable magnesium implants.

关键词： Plasma electrolytic oxidation Bioactive coatings Tantalum pentoxide Simulated body fluid(SBF) Apatite formation Histology

Synthesis and performance of Zn–Ni–P thin films

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Chinese Physics B 2015年第3期24卷 259-268页

作者： v.Soare m.Burada i.Constantin m.Ghita v.Constantin F.miculescu A.m.Popescu New materials and Technologies Laboratory National Research and Development Institute for Nonferrous and Rare Metals-IMNR institute of Physical Chemistry "ilie murgulescu" Laboratory of Molten Salts University Polytehnica of Bucharest Center of Biomaterials (BIOMAT)

The electroplating of Zn–Ni–P thin film alloys from a sulfate bath containing phosphoric and phosphorous acid was investigated. The bath composition and the deposition parameters were optimized through Hull cell experiments, and the optimum experimental conditions were determined（p H = 2, temperature = 298–313 K, zinc sulfate concentration =30 g·L^-1, EDTA concentration = 15 g·L^-1, and current density = 1.0–2.0 A·dm^-2）. The SEm analysis of the coating deposited from the optimum bath revealed fine-grained deposits of the alloy in the presence of EDTA. Optical microscopy analysis indicated an electrodeposited thin film with uniform thickness and good adhesion to the steel substrate. The good adherence of the coatings was also demonstrated by the scratch tests that were performed, with a maximum determined value of 25 N for the critical load. Corrosion resistance tests revealed good protection of the steel substrate by the obtained Zn–Ni–P coatings, with values up to 85.89% for samples with Ni contents higher than 76%. The surface analysis of the thin film samples before and after corrosion was performed by X-ray photoelectron spectroscopy（XPS）.

关键词： thin film corrosion electrochemistry surface

Synthesis,structure and magnetic properties of Sm_(1.2)Ho_(0.8)Fe_(17)Hx(X=0;4.4)

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Journal of Rare Earths 2021年第9期39卷 1089-1094页

作者： S.v.veselova m.A.Paukov i.S.Tereshina v.N.verbetsky K.v.Zakharov D.i.Gorbunov A.N.vasiPev Faculty of Physics M.V.Lomonosov Moscow State UniversityMoscow 119991Russia Nuclear Fuel Cycle Department.Centrum vyzkumu Rez Hlavni 130Husinec-Rez 25068.Czech Republic immanuel Kant Baltic Federal University Kaliningrad 236004Russia Faculty of mathematics and Physics Charles UniversityPrague 12116Czech Republic Hochfeld-magnetlabor Dresden(HLD-EmFL) Helmholtz-Zentrum Dresden-RossendorfDresden 07328Germany f National Research South Ural State UniversityChelyabinsk 454080Russia

intermetallic compounds based on rare-earth metals and iron are by far the most promising materials for permanent mag *** this work,the multicomponent compound Sm_(1.2)Ho_(0.8)Fe_(17)was prepared by in duction *** hydride Sm_(1.2)Ho_(0.8)Fe_(17)H_(4.4)with a high hydrogen content was obtained by direct hydrogenation of the intermetallic *** rhombohedral Th2Zn17-type of structure(space group R3^(-)m)is inhere nt to parent compound and hydride as *** effect of hydrogenation on the magneric properties of Sm_(1.2)Ho_(0.8)Fe_(17)was *** temperature of the hydride Sm_(1.2)Ho_(0.8)-Fe_(17)H_(4.4)is higher than that of parent compound by△Tc=138 *** hydrogen embedded in Sm_(1.2)Ho_(0.8)Fe_(17)crystal lattice in creases the saturation magnetization(σs)at T=300 K,but does not significantly affect%at T=4.2 *** ferrimagnetic structure is retained in magnetic fields up to 58 T in the parent compound,while,in the hydride,there is a spin-reorie ntatio n phase transitio n observed at 55 *** is found that the parameter of the in tersublattice exchange interaction decreases significantly in the hydride Sm_(1.2)Ho_(0.8)Fe_(17)Hg_(4.4)(and in the nitride Sm_(1.2)Ho_(0.8)Fe_(17)N_(2.4))which is associated with boosting of the unit-cell volume and distances between magnetic ions.

关键词： intermetallic compound Hydride Crystal structure magnetization magnetic phase transition Exchange interaction

versatility of therapeutic reduction mammoplasty in oncoplastic breast conserving surgery

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World Journal of Surgical Procedures 2015年第3期5卷 217-222页

作者： Fernando Hernanz mónica González-Noriega Rocío vázquez Pérez manuel Gómez-Fleitas Department of Surgery Valdecilla Hospital

Oncoplastic breast conserving surgery is the gold standard approach for the surgical treatment of early breast cancer. There is a well defined technique named "therapeutic mammoplasty" which is characterized for using a reduction mammaplasty technique to treat breast cancer conservatively. in our current practice, "therapeutic mammoplasty" or therapeutic reduction mammaplasty is our favorite oncoplastic breast conserving approach which it used in almost half of our patients. This technique is very versatile allows us the resection of tumors located in all breast quadrants of patients with moderate-to large-sized breasts. We describe a series of 57 patients who were treated using a therapeutic reduction mammaplasty. All surgical procedures were carried out by one comprehensive breast surgeon who planned and designed the surgery performing both oncologic and reconstructive procedures. Surgical margins were insufficient in eight patients(14%). Nine patients(15.8%) had a complication in early postoperative period and in one of them adjuvant radiotherapy was delayed four months due to a wound dehiscence. The rate of synchronous contralateral symmetrization was 31.6%. Our conclusion is that reduction mammaplasty is a useful and safe skill to treat breast cancer conservatively playing a very important role therefore it must be situated in the priority of learning objectives.

关键词： Breast conserving surgery Oncoplastic Oncoplastic breast surgery Reduction mammoplasty Therapeutic mammaplasty