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Blood pressure gradients in cerebral arteries:a clue to pathogenesis of cerebral small vessel disease

Stroke & Vascular Neurology 2017年第3期2卷 108-117页

作者： Pablo J Blanco lucas O müller J David Spence National Laboratory for Scientific Computing PetrópolisBrazil National Institute of Science and Technology in medicine Assisted by Scientific Computing INCT-MACCPetrópolisBrazil Stroke Prevention&Atherosclerosis Research Centre Robarts Research InstituteWestern UniversityLondon

rationale The role of hypertension in cerebral small vessel disease is poorly *** the base of the brain(the‘vascular centrencephalon’),short straight arteries transmit blood pressure directly to small resistance vessels;the cerebral convexity is supplied by long arteries with many branches,resulting in a drop in blood *** small vessel disease(lipohyalinosis)causes the classically described lacunar infarctions at the base of the brain;however,periventricular white matter intensities(WmIs)seen on mRI and WmI in subcortical areas over the convexity,which are often also called‘lacunes’,probably have different *** We studied pressure gradients from proximal to distal regions of the cerebral vasculature by mathematical *** and results Blood flow/pressure equations were solved in an Anatomically Detailed Arterial Network(ADAN)model,considering a normotensive and a hypertensive *** parameters were suitably modified to account for structural changes in arterial vessels in the hypertensive *** predict a marked drop in blood pressure from large and medium-sized cerebral vessels to cerebral peripheral *** blood pressure in the brachial artery is 192/113 mm Hg,the pressure in the small arterioles of the posterior parietal artery bed would be only 117/68 mm *** the normotensive case,with blood pressure in the brachial artery of 117/75 mm Hg,the pressure in small parietal arterioles would be only 59/38 mm *** These findings have important implications for understanding small vessel *** marked pressure gradient across cerebral arteries should be taken into account when evaluating the pathogenesis of small WmIs on *** small vessel disease,affecting the arterioles at the base of the brain should be distinguished from small vessel disease in subcortical regions of the convexity and venous disease in the periventricular white matter.

关键词： cerebral Blood pathogenesis

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Habitat productivity is a poor predictor of body size in rodents

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Current Zoology 2020年第2期66卷 135-143页

作者： Bader H.Alhajeri lucas m.V.Porto Renan maestri Department of Biological Sciences Kuwait UniversitySafat13060Kuwait Department of Ecology Universidade Federal do Rio Grande do SulPorto AlegreRS91501-970Brazil

The"resource availability hypothesis"predicts occurrence of larger rodents in more productive *** prediction was tested in a dataset of 1,301 rodent *** used adult body mass as a measure of body size and normalized difference vegetation index(NDVI)as a measure of habitat *** utilized a cross-species approach to investigate the association between these *** was done at both the order level(Rodentia)and at narrower taxonomic *** applied phylogenetic generalized least squares(PGLS)to correct for phylogenetic *** relationship between body mas and NDVI was also investigated across rodent *** controlled for spatial autocorrelation using generalized least squares(GLS)*** cross-species approach found extremely low support for the resource availability *** was reflected by a weak positive association between body mass and NDVI at the order *** find a positive association in only a minority of rodent *** best fit GLS model detected no significant association between body mass and NDVI across ***,our results do not support the view that resource availability plays a major role in explaining geographic variation in rodent body size.

关键词： Bergmann's rule body size(body mass) habitat productivity heat conservation hypothesis normalized difference vegetation index(NDVI) resource availability hypothesis

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New guidance for using t-SNE:Alternative defaults,hyperparameter selection automation,and comparative evaluation

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Visual Informatics 2022年第2期6卷 87-97页

作者： Robert Gove lucas Cadalzo Nicholas Leiby Jedediah m.Singer Alexander Zaitzeff Two Six Technologies USA

We present new guidelines for choosing hyperparameters for t-SNE and an evaluation comparing these guidelines to current *** guidelines include a proposed empirically optimum guideline derived from a t-SNE hyperparameter grid search over a large collection of data *** also introduce a new method to featurize data sets using graph-based metrics called scagnostics;we use these features to train a neural network that predicts optimal t-SNE hyperparameters for the respective data *** neural network has the potential to simplify the use of t-SNE by removing guesswork about which hyperparameters will produce the best *** evaluate and compare our neural network-derived and empirically optimum hyperparameters to several other t-SNE hyperparameter guidelines from the literature on 68 data *** hyperparameters predicted by our neural network yield embeddings with similar accuracy as the best current t-SNE *** our empirically optimum hyperparameters is simpler than following previously published guidelines but yields more accurate embeddings,in some cases by a statistically significant *** find that the useful ranges for t-SNE hyperparameters are narrower and include smaller values than previously reported in the ***,we also quantify the potential for future improvements in this area:using data from a grid search of t-SNE hyperparameters we find that an optimal selection method could improve embedding accuracy by up to two percentage points over the methods examined in this paper.

关键词： Dimensionality reduction machine learning t-SNE

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Concordance among pulse wave velocity assessment methods: A network meta-analysis

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中华医学杂志(英文版) 2024年第17期137卷 2137-2139页

作者： Cavero-Redondo Iván Sequí-Domínguez Irene Saz-Lara Alicia Garcia-Klepzig Jose Luis Lucerón-lucas-Torres maribel martínez-García Irene álvarez-Bueno Celia martínez-Vizcaíno Vicente CarVasCare Research Group Facultad de Enfermería de Cuenca Universidad de Castilla-La Mancha Cuenca Spain Facultad de Ciencias de la Salud Universidad Autónoma de Chile Talca Chile Health and Social Research Center Universidad de Castilla-La Mancha Cuenca Spain Internal medicine Department San Carlos University Hospital Madrid Spain Universidad Politécnica y Artística del Paraguay Asunción Paraguay

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Concerns about the application of resistance exercise with blood-flow restriction and thrombosis risk in hemodialysis patients

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Journal of Sport and Health Science 2024年第4期13卷 548-558,F0003页

作者： Hugo de Luca Correa Lysleine Alves Deus Dahan da Cunha Nascimento Nicholas Rolnick Rodrigo Vanerson Passos Neves Andrea Lucena Reis Thais Branquinho de Araujo Carmen Tzanno-martins Fernanda Silveira Tavares Luiz Sinesio Silva Neto Claudio Avelino Rodrigues Santos Paolo lucas Rodrigues-Silva Fernando Honorato Souza Vitoria marra da motta Vilalva mestrinho Rafael Lavarini dos Santos Rosangela Vieira Andrade Jonato Prestes Thiago dos Santos Rosa Post-graduate Program of Physical Education Catholic University of BrasıliaBrasılia 71966-700Brazil The Human Performance mechanic Lehman CollegeNew YorkNY 10011USA Clinical Group Home Dialysis Center and RenalClass Sao Paulo 01239-040Brazil Department of medicine Catholic University of BrasıliaBrasılia 71966-700Brazil Faculty of medicine Federal University of TocantinsTocantins 77001-090Brazil Embrapa Genetic Resources and Biotechnology Brasılia 70770-917Brazil Graduate Program of Genomic Sciences and Biotechnology Brasılia 71966-700Brazil

Background:Hemodialysis(HD) per se is a risk factor for *** the growing body of evidence on blood-flow restriction(BFR) exercise in HD patients,identification of possible risk factors related to the prothrombotic agent D-dimer is required for the safety and feasibility of this training *** aim of the present study was to identify risk factors associated with higher D-dimer levels and to determine the acute effect of resistance exercise(RE) with BFR on this ***:Two hundred and six HD patients volunteered for this study(all with a glomerular filtration rate of mL/min/1.73 m2).The RE+BFR session consisted of 50% arterial occlusion pressure during 50 min sessions of HD(intradialytic exercise).RE repetitions included concentric and eccentric lifting phases(each lasting 2 s) and were supervised by a strength and conditioning ***:Several variables were associated with elevated levels of D-dimer,including higher blood glucose,citrate use,recent cardiovascular events,recent intercurrents,higher inflammatory status,catheter as vascular access,older patients(>70 years old),and HD ***,RE+BFR significantly increases D-dimer after 4 *** with borderline baseline D-dimer levels(400-490 ng/mL) displayed increased risk of elevating D-dimer over the normal range(≥500 ng/mL).Conclusion:These results identified factors associated with a heightened prothrombotic state and may assist in the screening process for HD patients who wish to undergo RE+BFR.D-dimer and/or other fibrinolysis factors should be assessed at baseline and throughout the protocol as a precautionary measure to maximize safety during RE+BFR.

关键词： Blood-flow restriction Chronic kidney disease Coagulation Hemodialysis Vascular occlusion exercises

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An app to assist farmers in the identification of diseases and pests of coffee leaves using deep learning

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Information Processing in Agriculture 2022年第1期9卷 38-47页

作者： Jose G.m.Esgario Pedro B.C.de Castro lucas m.Tassis Renato A.Krohling LABCIN-Nature Inspired Computing Federal University of Espirito SantoAv.Fernando Ferrari514CEP 29075-910 VitoriaEspırito SantoESBrazil LABCIN-Nature Inspired Computing and PPGI-Graduate Program in Computer Scienceand Production Engineering DepartmentFederal University of Espirito SantoAv.Fernando Ferrari514CEP 29075-910 VitoriaEspırito SantoESBrazil

In recent years,deep learning methods have been introduced for segmentation and classi-fication of leaf lesions caused by pests and *** the commonly used approaches,convolutional neural networks have provided results with high *** purpose of this work is to present an effective and practical system capable of seg-menting and classifying different types of leaf lesions and estimating the severity of stress caused by biotic agents in coffee leaves using convolutional neural *** proposed approach consists of two stages:a semantic segmentation stage with severity calculation and a symptom lesion classification *** stage was tested separately,highlighting the positive and negative points of each *** obtained very good results for the severity estimation,suggesting that the model can estimate severity values very close to the real *** the biotic stress classification,the accuracy rates were greater than 97%.Due to the promising results obtained,an App for Android platform was developed and imple-mented,consisting of semantic segmentation and severity calculation,as well as symptom classification to assist both specialists and farmers to identify and quantify biotic stresses using images of coffee leaves acquired by smartphone.

关键词： Convolutional neural networks Semantic segmentation Coffee leaf Pests and diseases App.development

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A Long-Range Generalized Predictive Control Algorithm for a DFIG Based Wind Energy System

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IEEE/CAA Journal of Automatica Sinica 2019年第5期6卷 1209-1219页

作者： J.S.Solis-Chaves lucas L.Rodrigues C.m.Rocha-Osorio Alfeu J.Sguarezi Filho the Department of Energy Engineering at the Federal University of ABC-UFABC Santo AndreSPBrazil

This paper presents a new Long-range generalized predictive controller in the synchronous reference frame for a wind energy system doubly-fed induction generator based. This controller uses the state space equations that consider the rotor current and voltage as state and control variables, to execute the predictive control action. Therefore, the model of the plant must be transformed into two discrete transference functions, by means of an auto-regressive moving average model, in order to attain a discrete and decoupled controller, which makes it possible to treat it as two independent single-input single-output systems instead of a magnetic coupled multiple-input multiple-output system. For achieving that, a direct power control strategy is used, based on the past and future rotor currents and voltages estimation. The algorithm evaluates the rotor current predictors for a defined prediction horizon and computes the new rotor voltages that must be injected to controlling the stator active and reactive powers. To evaluate the controller performance, some simulations were made using matlab/Simulink. Experimental tests were carried out with a small-scale prototype assuming normal operating conditions with constant and variable wind speed profiles. Finally, some conclusions respect to the dynamic performance of this new controller are summarized.

关键词： Direct power control doubly-fed induction generator flux oriented control generalized predictive control long-range predictive control wind energy systems

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Detection of presumed genes encoding beta-lactamases by sequence based screening of metagenomes derived from Antarctic microbial mats

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Frontiers of Environmental Science & Engineering 2019年第3期13卷 173-184页

作者： Gaston Azziz matias Gimenez Hector Romero Patricia m. Valdespino-Castillo Luisa I. Falcon lucas A. m. Ruberto Walter P. mac Cormack Silvia Batista molecular microbiology Unit Clemente Estable Biological Research Insitute Montevideo 11600 Uruguay microbiology Laboratory Faculty of Agronomy UdelaR Montevideo 12900 Uruguay Genome Organization and Evolution Laboratory Ecology and Evolution Department Faculty of Sciences UdelaR Montevideo 11400 Uruguay molecular Biophysics and Integrated Bioimaging BSISB Imaging Program Lawrence Berkeley National Laboratory Berkeley CA 94720 USA Bacteial Ecology Laboratory Ecology Institute National Autonomous University of Mexico CDMX 04510 Mexico UN Am Yucatan Technology and Science Park Merida 97302 Mexico Argentine Antarctic Institute Buenos Aires 1650 Argentina Biotechnology Unit Faculty of Pharmacy and Biochemistry Nanobiotec Institute UBA-CONICET Buenos Aires 1113 Argentina

Analysis of environmental samples for bacterial antibiotic resistance genes may have different objectives and analysis strategies. In some cases, the purpose was to study diversity and evolution of genes that could be grouped within a mechanism of antibiotic resistance. Different protocols have been designed for detection and confirmation that a functional gene was found. In this study, we present a sequence-based screening of candidate genes encoding beta-lactamases in 14 metagenomes of Antarctic microbial mats. The samples were obtained from different sites, representing diverse biogeographic regions of maritime and continental Antarctica. A protocol was designed based on generation of Hidden markov models from the four beta-lactamase classes by Ambler classification, using sequences from the Comprehensive Antibiotic Resistance Database (CARD). The models were used as queries for metagenome analysis and recovered contigs were subsequently annotated using RAST. According to our analysis, 14 metagenomes analyzed contain A, B and C beta-lactamase genes. Class D genes, however, were identified in 11 metagenomes. The most abundant was class C (46.8%), followed by classes B (35.5%), A (14.2%) and D (3.5%). A considerable number of sequences formed clusters which included, in some cases, contigs from different metagenomes. These assemblies are clearly separated from reference clusters, previously identified using CARD beta-lactamase sequences. While bacterial antibiotic resistance is a major challenge of public health worldwide, our results suggest that environmental diversity of beta-lactamase genes is higher than that currently reported, although this should be complemented with gene function analysis.

关键词： Beta-lactamases Antibiotic resistance coding genes metagenomes Antarctic microbial mats

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Changes in higher order aberrations after central corneal regularization-a comparative two-year analysis of a semiautomated topography-guided photorefractive keratectomy combined with corneal cross-linking

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Eye and Vision 2020年第1期7卷 99-108页

作者： Katja C.Iselin Philipp B.Baenninger lucas m.Bachmann Frank Bochmann michael A.Thiel Claude Kaufmann Department of Ophthalmology Lucerne Cantonal HospitalLucerneSwitzerland medignition Healthcare Innovations ZurichSwitzerland

Background:The optical quality in progressive keratoconus deteriorates due to ectasia and distortion of the corneal shape and *** corneal cross-linking(CXL)aims at stopping disease progression,“CXL-Plus”combines CXL with excimer laser ablation to improve visual *** Corneal Regularization(CCR)represents a therapeutic excimer laser modality specifically designed to smoothen the ectatic corneal shape and to reduce higher order aberrations(HOA).We set out to compare CXL-Plus,consisting of CXL combined with CCR,with CXL by itself for patients with progressive ***:Retrospective 2-year matched group analysis of patients who either underwent CXL-Plus(n=28)or CXL as a sole procedure(n=28)for progressive *** outcome parameters were HOA,visual function and tomographic results 12 and 24 months ***:After 12 months,the total HOA root mean square wavefront error was reduced from 0.79±0.30 to 0.40±0.19μm(CXL-Plus;pm 0.71±0.28 to 0.73±0.36μm(CXL;p=0.814).Uncorrected distance visual acuity improved from 0.70±0.35 to 0.36±0.29 logmAR(CXL-Plus;p=0.0002)and from 0.65±0.39 to 0.46±0.37 logmAR(CXL;p=0.067),translating to gains of three or more lines in 50%(CXL-Plus)and 36%(CXL)of *** steepest keratometry value(Kmax)regressed by 5.84 D(CXL-Plus;pmeters a statistically significant change could be shown between 12 and 24 ***:CXL-Plus in the form of a CCR reduces HOA and Kmax more effectively than CXL as a sole procedure.

关键词： Keratoconus Corneal cross-linking CXL-plus Photorefractive keratectomy Central corneal regularization Higher order aberrations Coma-like aberrations

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Rare earth metal as a dopant element:Cerium ion as an articulator in hexavalent chromium removal by magnetic iron oxides

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Journal of Rare Earths 2023年第10期41卷 1616-1626,I0006页

作者： Pricila maria Batista Chagas maísa m.m.Lima Aline Aparecida Caetano lucas Bragança Carvalho Nayra maria de Abreu Piva maria Eduarda Resende Luiz Iara do Rosário Guimarães Laboratory of Environmental Catalysis and New materials Department of ChemistryFederal University of LavrasCEP 37200-900LavrasMGBrazil Department of Viticulture&Enology University of CaliforniaDavisCA95616USA Institute of Science and Technology São Paulo State University18087-180SorocabaBrazil

This study highlights introducing the rare earth metal cerium(Ce(Ⅳ))into the structure of magnetite(Fe_(3)O_(4))to achieve enhanced adsorptive properties for the removal of chromium(Cr(VI))from an aqueous *** ratios of Ce(Ⅳ)were introduced into the iron oxide matrix,termed FeCe-5,FeCe-10,and *** numerical values correspond to the nominal content of the dopant element added to the synthesis *** solid materials were characterized for morphology and chemical structure,and N_(2)physical adsorption/desorption measurements were *** solid materials doped with Ce(IV)have a high surface area compared to Fe_(3)O_(4),and the solid material with the highest content of the dopant ion(Ce(IV))has a 4-fold greater surface *** increase in the dopant content in the iron oxide structure leads to a total chromium removal of 93.3%.Isotherms studies on the solid materials show that chromium adsorption follows the Langmuir *** adsorption capacity to Fe_(3)O_(4)is 12.59 mg/g and FeCe-10 is 22.49 mg/g at 35℃.By fitting the kinetic and isothermal models,it is found that for the Fe_(3)O_(4)and FeCe-10 materials Cr(VI)removal occurs in very different ways,attributed to the different surface areas and compositions of the oxide,with the formation of the goethite(α-FeOOH)*** FeCe-10reuse process was performed and the removal capacity the Cr(VI)is reduced after the first *** result is attributed to a strong and irreversible adsorption of Cr(VI)on the FeCe-10.

关键词： Bimetallic oxides Fe-Ce interaction Oxygen vacancies Adsorption Cr(Ⅵ) Rare earths

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