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Modulation of CNS excitability by water movement. the D<sub>2</sub>O effects on the non-linear neuron-glial dynamics

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Journal of Biophysical Chemistry 2011年第3期2卷 353-360页

作者： vera maura fernandes de lima Wolfgang Hanke 不详

Macroscopic spatiotemporal patterns arising in grey matter may explain the clinical manifestations of several functional neurological syndromes (migraine aura, epilepsies). detailed descriptions of these patterns in central grey matter and their physicochemical or pharmacological manipulations can be useful in many scientific fields ranging from drug design to functional brain imaging. These evanescent dynamic structures are electrochemical in nature and show macroscopic tissue polarization due to coupled and macroscopic flow of ions and water across, along and between neuronal and glial membranes. So far the importance of the water flow in the CNS functional syndromes has been examined by manipulations of water channels aquaporines (AQP). In this paper we show the result of substituting H2O for D2O in retinal spreading depression experiments. This inverts the present logic by changing the flow in the water channels in intact tissue and observing the evolution of electrochemical patterns and recording the optical profiles of excitation waves in isolated chick retinas. D2O flow through AQPs is ~20% slower than that of H2O. The slower flux disturbs the tight coupling between ion and water flows across membranes and slowdown the Na-KATPase rate of change with metabolic consequences for the tissue. The whole tissue excitability shifts in a non-stationary manner toward a non-excitable state.

关键词： Retinal Spreading depression D2O Neuron-Glial-Dynamics

The Spreading depression Propagation: How Electrochemical Patterns Distort or Create Perception

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Open Journal of Biophysics 2021年第2期11卷 133-146页

作者： vera maura fernandes de lima Alfredo Pereira Junior Guilherme lima de Oliveira Centro de Biotecnologia CNEN/IPEN-SP S&atilde o Paulo Brazil department of Human and Nutritional Sciences Biosciences Inst. UNESP Botucatu S&atilde o Paulo Brazil S&atilde o Paulo S&atilde o Paulo Brazil

At the transition from quiescence to propagating waves recorded in isolated retinas, a circular electric current closes in the extracellular matrix;this circular current creates a magnetic torus flow that, when entering quiescent tissue in front of the wave, recruits elements and when leaving behind, helps to build the absolute refractory state. The waving magnetic torus is the consequence of the vortex effect and explains the energy boost that drives propagation. Methods: We interpret experimental results from intrinsic and extrinsic fluorescence dyes, voltage, calcium and pH sensitive, optical signals from isolated retinas, and time series recordings using ion exchange resins: Ca, K, pH, Na, Cl recorded extracellularly at retinas, cerebellums and cortices coupled to spreading depression waves. Finally, we checked the ECoG activity, also a time series, at the transition from after discharges to spreading depression in rat hippocampus. Results: The integrated assessment of the diversified measurements led to the realization that the magnetic flow at the wavefront is a major contributor to the wave propagation mechanisms. This flow couples mass and charge flows as a swirling torus from excited to quiescent tissue. Conclusions: An alternative model of the brain is possible, apart from the classical HH and molecular biology model. Physical chemistry of charged gels and its flows explains the results. The conceptual framework uses far from equilibrium thermodynamics.

关键词： Brain Electrochemistry Retinal Model Resonance Spreading depression Functional CNS Syndromes Vortex Effect

The Tight Coupling and Non-Linear Relationship between the Macroscopic Electrical and Optical Concomitants of Electrochemical CNS Waves Reflect the Non-Linear Dynamics of Neural Glial Propagation

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Open Journal of Biophysics 2015年第1期5卷 1-20页

作者： vera maura fernandes de lima José Roberto Castilho Piqueira Wolfgang Hanke CCO Medical School Universidade Federal de Sao Joao Del Rei Sao Joao Del Rei Brazil LIM-26 Faculty of Medicine USP Sao Paulo Brazil Laboratory of Automation and Control Escola Politecnica USP Sao Paulo Brazil Membrane Physiology Division Physiology Institute 230 Hohenheim University Stuttgart Germany

In isolated chick retina, the visualization of electrochemical self-organized patterns is possible due to the presence of macroscopic intrinsic optical signals (IOSs). Isolated circular waves, standing patterns, and self-sustained sequences of spirals are all easily obtained using an IOS approach. In this paper we present the tight coupling and non-linear relationship between optical and electrical wave concomitants, and potassium-induced whole tissue excitability changes. Elementary statistical methods and time series analyses were applied to two sets of data: 1) solitary circular retinal spreading depression waves, and 2) tissue response to exogenous potassium fast pulses. The results were interpreted from the point of view of non-linear thermodynamical concepts and volume phase transitions in polyanionic gels according to the Tasaki action potential model. From these and previous results, it is clear that the glial network and extracellular matrix contribute to the propagation and emergence of these patterns.

关键词： Glial Network Extracellular Matrix KCl Spreading depression Excitable Media

An Endogenous Feedback and Entropy Analysis in Machine Learning Model for Stock’s Return Forecast

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Intelligent Automation & Soft Computing 2023年第6期36卷 3175-3190页

作者： Edson Vinicius Pontes Bastos Jorge Junio Moreira Antunes Lino Guimaraes Marujo Peter fernandes Wanke Roberto Ivo da Rocha lima Filho Instituto Alberto Luiz Coimbra de Pos-Graduação e Pesquisa de Engenharia-COPPE Universidade Federal do Rio de Janeiro(UFRJ)Rio de Janeiro21941-598Brasil Instituto de Pos-Graduacao em Administracao-Coppead Universidade Federal do Rio de Janeiro(UFRJ)21941-918Brasil

Stock markets exhibit Brownian movement with random,non-linear,uncertain,evolutionary,non-parametric,nebulous,chaotic characteristics and dynamism with a high degree of *** an algorithm to predict returns for decision-making is a challenging *** addition,the choice of vari-ables that will serve as input to the model represents a non-triviality,since it is possible to observe endogeneity problems between the predictor and the predicted ***,the goal is to analyze the endogenous origin of the stock return prediction model based on technical *** this,we structure a feed-for-ward neural *** evaluate the endogenous feedback between the pre-dicted returns and technical analysis indicators based on the generated *** is possible to predict the *** high accuracy of the model indicates that,during the test period,there is a hit rate close to 76%.Regarding endogeneity,the term of interest and the return are the variables that influence the largest number of *** results will help investors build investment strategies based on this expert system applied to forecasting.

关键词： Forecast endogeneity neural networks differential evolution stochastic optimization

A Brief Review on Hydroxyapatite Nanoparticles Interactions with Biological Constituents

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Journal of Biomaterials and Nanobiotechnology 2022年第1期13卷 24-44页

作者： Flávia Carolina lima Torres Edésia Martins Barros de Sousa Marcelo fernandes Cipreste Serviç o de Nanotecnologia (SENAN) Centro de Desenvolvimento da Tecnologia Nuclear (CDTN) Belo Horizonte Brazil Faculdade de Farmácia Universidade Federal de Minas Gerais (UFMG) Belo Horizonte Brazil

With the pursuit of new cancer therapies and more effective treatment to diseases in the last decades, nanotechnology has been an important ally for healthcare professionals and patients in critical clinical conditions. Nanomaterials offer an alternative way to deliver toxic chemotherapeutic drugs to specific biological tissues, specific cells or specific microbial beings, resulting in avoidance of strong side effects or resilience to effective drugs. Among these materials, stands out the hydroxyapatite nanoparticles, a ceramic class of calcium phosphates that present chemical and structural similarities with the mineral phase of the human skeleton’s bone matrix, resulting in important biological features, such as biocompatibility, osteoconductive, osteoinduction and osteoaffinity, which led to a lot of scientific researches to apply these nanoparticles for bone diseases diagnosis and therapeutics. Due to the hydroxyapatite biological activities and due to the possibility to promote chemical and physical modifications in these nanoparticles, they can interact with biological cells or microorganisms in different ways, resulting in multiple potentialities to be explored such as apoptosis induction to cancerous cells, osteogenesis promotion, cellular proliferation, angiogenesis and tissue recovery, in addition to promote cell adhesion and cell uptake. Furthermore, chemical and physical modifications, such as surface functionalization, dopant inclusions and radiolabeling process, allow scientists to track the particle activities in biological environments. In the last decades of scientific productions, the literature brings together important data on how hydroxyapatite nanoparticles interact with biological tissues and such data are crucial for the development of more effective therapeutic and diagnostic agents. In the present review, we intend to compile scholarly information to explore the biological relations of nanosized hydroxyapatite with the human cellular enviro

关键词： Biomaterials Nano-Hydroxyapatite Cell Interactions Chemical Modifications Tissue Engineering Theranostics

Photoluminescence emissions of Ca_(1-x)WO_(4):xEu^(3+):Bridging between experiment and DFT calculations

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Journal of Rare Earths 2022年第10期40卷 1527-1534页

作者： Amanda fernandes Gouveia Marcelo Assis Lara Kelly Ribeiro Aline Estefany Brandao lima Eduardo de Oliveira Gomes Daniele Souza Yara Gobato Galvao Ieda Lucia Viana Rosa Geraldo Eduardo da Luz Jr Eva Guillamón Elson Longo Juan Andrés Miguel Angel San-Miguel department of Physical and Analytical Chemistry University Jaume I(UJI)12071CastelloSpain Institute of Chemistry State University of Campinas(Unicamp)13083-970CampinasSPBrazil CDMF Federal University of S?o Carlos(UFSCar)P0.Box 67613565-905Sao CarlosSao PauloBrazil departamento de Química Federal University of Piauí(UFPI)64049-550TeresinaPiautBrazil Physics department Federal University of S?o Carlos(UFSCar)P.0.Box 67613565-905Sao CarlosSao PauloBrazil

In this work,the impact of the doping process on the photoluminescence emission of CaWO_(4) as a function of the concentration of Eu^(3+) cation(0.01 mol%,0.02 mol%,0.04 mol%,0.06 mol%,0.08 mol%,and 0.10 mol%) is discussed in ***_(1-x)WO~4:xEu^(3+) samples were successfully synthesized by a simple coprecipitation method followed by microwave *** blue shift in the absorption edge confirms the quantum confinement effect and the band gap energy covers the range from 3.91 to 4.18 eV,as the amount of Eu^(3+) cations *** experimental results are sustained by first-principles calculations,at the density functional theory level,to decipher the geometry and electronic properties,thereby enabling a more accurate and direct comparison between theory and experiment for the Ca_(1-x)WO_(4):xEu^(3+) structure.

关键词： Ca_(1-x)WO_(4):xEu^(3+) DFT calculations Photoluminescence emissions Rare earths

Effects of Soluble Silicate and Nanosilica Application on Rice Nutrition in an Oxisol

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Pedosphere 2018年第4期28卷 597-606页

作者： Rita de Cassia FELIX ALVAREZ Renato de Mello PRADO Guilherme FELISBERTO Angelica Cristina fernandes deUS Raimundo Leonardo lima de OLIVEIRA Federal University of Mato Grosso do Sul Chapadao do Sul 79560-000 (Brazil) University of the State of Sao Paulo UNESP School of Agronomic Sciences Department of Soils and Fertilizers Jaboticabal 14884-900 (Brazil)

Silicon(Si) has been supplied to plants via application of calcium silicate to soil; however, high doses of calcium silicate are required because of its low solubility. Nanoparticles can reduce Si doses and be applied to seeding furrows. This study investigated the effects of liquid Si sources, i.e., highly soluble silicate(115.2 g L^(-1) Si and 60.5 g L^(-1) Na_2O) and nanosilica(der greanhouse condistions. The treatments included the application of nanosilica and soluble silicate to seeding furrows at Si doses of 0, 605, 1 210,and 2 420 g ha^(-1). Plant uptake and treatment effects were evaluated by measuring C and lignin contents, Si, N, and P accumulation,physiological characteristics, and grain yield of rice. The deposition of silica bodies and amorphous silica in the flag leaves was analyzed using scanning electron microscopy. Application of liquid Si increased Si accumulation in rice by 47.3% in relation to the control(0 g ha^(-1) Si), regardless of the Si sources used. Nanosilica application increased leaf lignin content by 112.7% when compared to that in the control. Silicon moderately affected the net C assimilation(increased by 1.83%) and transpiration rates(increased by 48.3%);however, Si influenced neither plant growth nor grain yield of rice. These results are explained by the lack of biotic or abiotic stress in rice plants during the experiment. To the best of our knowledge, in Brazilian agriculture, this is the first report on the use of nanosilica as a Si fertilizer and its effect on plant nutrition. This study provides evidence that rice plants absorb and accumulate nanoparticles;however, further studies are required to investigate the use of nanoparticles in other plant species.

关键词：植物营养硅酸盐植物生理学扫描电子显微镜谷物产量植物吸收高剂量植物生长

Multielement determination in orange juice by ICP-MS associated with data mining for the classification of organic samples

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Information Processing in Agriculture 2017年第3期4卷 199-205页

作者： Christian Turra Marcio Dias de lima Elisabete A.de Nadai fernandes Marcio Arruda Bacchi Fernando Barbosa Jr. Rommel Barbosa Centro de Energia Nuclear na Agricultura Universidade de Sao PauloPiracicabaBrazil USP-Ribeirao Preto Brazil Instituto de Informatica Universidade Federal de GoiasGoianiaGOBrazil Instituto Federal de Educacao Ciencia e Tecnologia de Goias GoianiaGOBrazil

The aim of this study was to discriminate organic from conventional orange juice based on chemical elements and data mining applications.A comprehensive sampling of organic and conventional oranges was carried out in Borborema,state of Sao Paulo,*** fruits of the variety Valencia(Citrus sinensis(L.)Osbeck)budded on Rangpur lime(Citrus limonia Osbeck)were *** chemical elements were determined in 57 orange samples grown in organic and conventional *** order to classify these samples,data mining techniques(Support Vector Machine(SVM)and Multilayer Perceptron(MLP))were combined with feature selection(F-score and chi-squared).SVM with chi-squared had a better performance compared with the other techniques because it reached 93.00% accuracy using only seven chemical components(Cu,Cs,Zn,Al,Mn,Rb and Sr),and correctly classified 96.73% of the samples grown in an organic system.

关键词： Data mining Support vector machines Multilayer perceptron Orange juice Trace elements Inductively coupled plasma mass spectrometry(ICP-MS)

Epidemiological and clinical characteristics of COVID-19 in a Brazilian public hospital

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World Journal of Clinical Cases 2023年第8期11卷 1761-1770页

作者： Fillipe Dantas Pinheiro Luana Weber Lopes Rafael Santos Dantas Miranda Dórea Glauber Rocha lima Araújo Filipe Antônio França da Silva Breno Bittencourt de Brito Maria Luísa Cordeiro Santos Geovani Moreno Santos Júnior Maria Teresa Araújo de Lorenzo Barcia Renata de Amorim Marques AndréBezerra Botelho Anna Carolina Saúde Dantas Davi Tanajura Costa Adriano fernandes Teixeira Cláudio lima Souza Lucas Miranda Marques Guilherme Barretos Campos Márcio Vasconcelos Oliveira Dulciene Maria de Magalhães Queiroz Fabrício Freire de Melo Instituto Multidisciplinar em Saúde Universidade Federal da BahiaVitória da Conquista 45029-094BahiaBrazil Hospital Geral de Vitória da Conquista Vitória da Conquista 45030-160BahiaBrazil departamento de Ciências da Saúde Universidade Estadual do Sudoeste da Bahia(UESB)Vitória da Conquista 45083-900BahiaBrazil Faculdade de Medicina Universidade Federal de Minas GeraisBelo Horizonte 31270-901Minas GeraisBrazil

BACKGROUND The coronavirus disease 2019(COVID-19)pandemic has become a major health concern *** that context,the understanding of epidemiological and clinical features associated with the disease and its severity is crucial for the establishment of strategies aimed at disease control and *** To describe epidemiological features,signs,symptoms,and laboratory findings among severely ill COVID-19 patients from an inten-sive care unit in northeastern Brazil as well as to evaluate predictor factors for disease *** This is a prospective single-center study that evaluated 115 patients admitted to the intensive care unit in a northeastern Brazilian *** The patients had a median age of 65.60±15.78 *** was the most frequent symptom,affecting 73.9%of the patients,followed by cough(54.7%).Fever was reported in approximately one-third of patients and myalgia in 20.8%of the *** least two comorbidities were found in 41.7%of the patients,and hypertension was the most prevalent(57.3%).In addition,having two or more comorbidities was a predictor of mortality,and lower platelet count was positively associated with *** and vomiting were two symptoms that were predictors of death,and the presence of a cough was a protective *** This is the first report of a negative correlation between cough and death in severely ill severe acute respiratory syndrome coronavirus 2-infected *** associations between comorbidities,advanced age,and low platelet count and the outcomes of the infection were similar to the results of previous studies,highlighting the relevance of these features.

关键词： COVID-19 Epidemiology Symptoms Comorbidities Laboratory parameters