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Effects of aeration on the suspended matter from a tropical and eutrophic estuary

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Journal of Environmental Sciences 2019年第12期31卷 175-186页

作者： Natascha Krepsky maria das gracas S.Bispo Luiz F.Fontana Frederico S.da Silva Jodo P.M.Torres Olaf Malm cleverson G.Silva Mirian A.c.crapez Laboratory of Marine Geology Fluminense Federal UniuersityAue.Gen.Milton Tauares de Souza s/n°-Gragoata24210-346 NiterdiRJBrazil Radioisotopes Laboratory Eduardo Penna Franca Biophysics Institute Carlos Chagas FilhoFederal University of Rio de JaneiroAu.Carlos Chagas Filho373 CCS-Bl.G21941-902 Rio de JaneiroRJBrazil Marine Biology Department Fluminense Federal UniversityR.Mario Santos Bragas/nNiteroi24.020-141 NiteroiRJBrazil

A comprehensive understanding of the complex biogeochemical interactions between organic matter and persistent contaminants in the suspended matter is vital for ecoefficient estuary ***,little is known regarding aeration effects in suspended particulate ***,this study aimed to investigate the effects of aeration on the suspended matter from a Tropical and Eutrophic estuarine *** water with 60 g/L of suspended particulate matter(SPM)was collected from Guanabara Bay,Rio de Janeiro,Brazil,transferred to experimental boxes and aerated for 61 *** aggregates monitoring included abiotic variables measurements and,determination of total organic matter(TOM),biopolymers composition,bacterial activity,trace metals,and polycyclic aromatic hydrocarbons(PAHs)*** aeration enhanced dissolved oxygen(DO)concentration and the redox potential(Eh).However,from days 0 to 61 the predominant bacterial activities were denitrification and *** transport system activity increased after day 10,and aerobic activity was detected after day *** summary,aeration increased aerobic bacterial activity,lipids(LIP)and trace metal concentrations,although diminished protein/carbohydrate ratio and PAH *** metals concentration(Ni,Pb,cu,cr,Mn,and Fe)were the highest on day 19 when the p H was *** presented toxic values(cu>20.0μg/g).The p H showed a strong negative correlation with Eh(r=-0.94;pcidic environment(p H≤5.9)in marine ecosystems with high loads of toxic trace metals is unsafe for ***,managers must be aware of the environmental and biological risks of introducing the aeration technique into a eutrophic marine environment.

关键词： Mixed-pollution Remediation Acidification Esterases enzymes Biopolymer

Sub-chronic effects of a Phthirusa pyrifolia aqueous extract on reproductive function and comparative hormone levels in male rats

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Asian Pacific Journal of Tropical Biomedicine 2016年第3期6卷 202-210页

作者： Romero Marcos Pedrosa Brandao-costa Vivianne Ferreira Araujo Elizabeth Neves maria Tereza Santos correia Ana Lucia Figueiredo Porto maria das gracas carneiro-da-cunha Department of Biochemistry Center of Biological Sciences Federal University of Pernambuco Keizo Asami Laboratory of Imunopathology LIKA/UFPE Department of Anatomy Federal University of Pernambuco Department of Animal Morphology and Physiology Federal Rural University of Pernambuco Keizo Asami Laboratory of Imunopathology LIKA/UFPE

Objective: To explore the effects of aqueous extract from Phthirusa pyrifolia leaves(67 mg/kg body weight for 12 days) on the reproductive function of male Wistar rats through oral ***: Animals(n = 30), aged 13 weeks and weighing(378.5 ± 5.0) g, were housed in a vivarium under controlled environmental conditions [photoperiod of 12 h light/dark,temperature of(23 ± 1)c] and were fed standard rations ad libitum. The experiment ran for 12 days, wherein animals were divided into three groups: negative control(n = 6)received water, positive control(n = 12) with finasteride at a concentration of 1.0 mg/kg;and a test group(n = 12) submitted to aqueous extract. At the end of the experiment, the animals were sacrificed and submitted to ***: The morphological results of the testes showed that the aqueous extract induced significant changes in the diameter and cross-sectional area of the seminiferous tubules as well as the thickness of the seminiferous epithelium. Furthermore, the extract was able to abruptly decrease testosterone concentrations by about 81.88% in the treated group when compared with the negative control,(47.0 ± 4.8) ng/d L and(255.0 ± 2.0) ng/d L,respectively, and 76.8%,(211.0 ± 8.7) ng/d L, when compared with finasteride. However,the extract causes neither liver damage nor impairment of renal ***: These results suggest that the high amounts of flavonoids shown to be in the extract may be responsible for its hepato-protective effects and suggest a possible decrease in the libido and reproduction of rats.

关键词： Reproductive function Phytochemical Testosterone Finasteride Phthirusa pyrifolia

Influence of fire on woody vegetation of savanna and forest formations in the cerrado biome

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林业研究:英文版 2023年第5期34卷 1207-1216页

作者： Aline das gracas costa Fillipe Tamiozzo Pereira Torres Gumercindo souza Lima Fabiano Rodrigues de Melo carlos Moreira Miquelino Eleto Torres Bruno Leao Said Schettini Vicente Paulo Santana Neto AndréLuiz Lopes de Faria Department of Forest Engineering Federal University of VicosaUFVVicosaMG 36570-900Brazil Department of Geography Federal University of VicosaUFVVicosaMG 36570-900Brazil

Wildfires have environmental,economic,and social impacts,and can shape the landscape and benefit ecosystems such as the *** study evaluated the diversity,similarity,and floristic and structural differences of woody savanna and forest formations of the cerrado,when affected and not affected by ***-eight 25-400m2 plots were randomly allocated and divided into Burnt cerrado and Unburnt cerrado,Burnt Forest,and Unburnt Forest,and divided into three levels of inclusion according to diameter class(smaller than 2 cm,2-5 cm and larger than5 cm).Species were identified,DBH and height measured,and phyto sociological parameters such as volume,diversity,and floristic similarity *** cerrado had lower diversity,density,and dominance at all inclusion levels compared to the Unburnt cerrado,and showed similarities between treatments at the inclusion *** Forest had smaller differences in diversity,density,and dominance than Unburnt *** formation was similar at level 1 of inclusion and in the total ***,it was dissimilar at lower *** lower density and diversity of species at the lowest levels of inclusion was associated with mortality from fire.

关键词： Biodiversity Brazil Burning Floristic Phytosociology

Litterfall dynamics and soil carbon and nitrogen stocks in the Brazilian palm swamp ecosystems

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Forest Ecosystems 2020年第3期7卷 499-510页

作者： Gracielle de Brito Sales Taynan Aquilles Marinho Lessa Daniela Aparecida Freitas maria das Dores Magalhães Veloso maria Ligia de souza Silva Luiz Arnaldo Fernandes Leidivan Almeida Frazão Instituto de ciências Agrárias Universidade Federal de Minas GeraisAvenida Universitária1000Montes ClarosMG39404-547Brazil Universidade Estadual de Montes claros Avenida Professor Rui Braga S/NMontes ClarosMG39401-089Brazil Universidade Federal de Lavras Campus UniversitárioCP 3037LavrasMG37299-000Brazil

Background: This study aimed to determine the litterfall production, accumulation, decomposition rate and nutrient stocks, and to estimate the soil carbon(c) and nitrogen(N) stocks in three palm swamp ecosystems with different land use intensities in the Southeast of ***: Three palm swamp ecosystems with different land use intensities were evaluated: Agua Doce(AD),conserved area;capivara(cV), area with small agricultural practices;and Buriti Grosso(BG), area with an intensive land use. Produced and accumulated litterfall from the cerrado areas surrounding the palm swamps were collected from October 2014 to September 2015, and the ca, Mg, K, and P concentrations were determined in the dry and rainy seasons. Soil samples were collected in the surrounding cerrado and within the palm swamps until 100 cm soil depth to determine bulk density and soil c and N contents and ***: Annual litterfall production in the cerrado surrounding palm swamps was similar in AD(3.58 Mg·ha^-1·year^-1) and cV(3.79 Mg·ha^-1·year^-1), and was lower in BG(2.84 Mg·ha^-1·year^-1), and was more intense during the dry season. Furthermore, litterfall accumulation was higher in cV(7.12 Mg·ha^-1·year^-1) and BG(6.75 Mg·ha^-1·year^-1), culminating in lower decomposition rates. AD showed the highest decomposition rate(0.60) due to its vegetation structure and conservation. The macronutrient contents from the production and accumulated litterfall had a low influence of the land use, decreasing in the following order: ca > K > Mg > P. Soils in cV and BG palm swamp areas showed higher values of c and N contents, due to the use of land for agricultural crops and cattle raising in an extensive(rangeland) system. The BG palm swamp, showed the highest c(124.03 Mg·ha^-1) and N(10.54 Mg·ha^-1) stocks due to the land use history with different agricultural practices over ***: The litterfall dynamics in the cerrado surrounding palm swamps was more affected by climatic variables t

关键词： Nutrient cycling Soil fertility Soil organic matter Decomposition rate

Morphophysiology of Germination among Seeds of Pau-rainha （centrolobium paraense） collected in the State of Roraima

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Journal of Agricultural Science and Technology(B) 2016年第6期6卷 371-379页

作者： Luis Augusto Melo Schwengber Oscar Jose Smiderle Aline das gracas souza Jose maria Arcanjo Alves Dalton Roberto Schwengber cylles Zara dos Reis Barbosa Postgraduate Program in Agronomy Universidade Federal de Roraima (UFRR) Boa Vista RR CEP 69300-000 Brazil Brazilian Agricultural Research corporation--Embrapa Roraima Boa Vista RR CEP 69301-970 Brazil Laboratory of Plant Tissue culture Federal University of Pelotas Campus Capao do Leao RS CEP 96010-900 Brazil

This work intended to characterize the seed morphology, water absorption patterns and to determine the vigor among different colored seeds of the species centrolobium paraense （Fabaceae）. For this purpose, samaras which were opened were collected from two sites---Agua Boa （AB） and Taiano （TAI） lo^ated in the state of Roraima, and the seeds screened by the coat coloration （light brown/intermediate brown/dark brown） for four conditions （two sites and two years of collection）. Evaluation of water absorption by the seeds at different periods, mass of 1,000 seeds, water content, electrical conductivity （Ec）, seedling emergence and emergence velocity （EV） were performed. The water absorption by the seeds of centrolobium paraense indicates coat permeability to water and distinct absorptions according to coat colorations. The Ec test is efficient in determining the physiological quality of seeds of centrolobium paraense. Seed coat coloration affects the physiological quality of the seeds of centrolobium paraense. It is possible to distinguish the seeds of AB and TAI into two degrees of physiological quality, the light brown-colored seeds being more vigorous.

关键词： centrolobium paraense water absorption curve electrical conductivity seed vigor seed coloring.

Essential Oils from Mentha viridis(L).*** Mentha pulegium L.:cytogenotoxic Effects on Human cells

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American Journal of Plant Sciences 2017年第6期8卷 1423-1437页

作者： Lucilene Fernandes Silva maria das gracas cardoso Paulo Sérgio castilho Preté maria Luisa Teixeira David Lee Nelson Maísa Lamounier Magalhaes Vanuzia Rodrigues Fernandes Ferreira Rafaela Vieira souza Luana Isac Soares Silvana Marcussi Departamento de Química Universidade Federal de LavrasCampus UniversitárioLavrasMinas GeraisBrasil Departamento de Química Universidade Federal dos Vales do Jequitinhonha e MucuriCampus UniversitárioDiamantinaMinas GeraisBrasil Departamento de ciência dos Alimentos Universidade Federal de LavrasCampus UniversitárioLavrasMinas GeraisBrasil

The essential oils from Mentha viridis (L). L. and Mentha pulegium L. were studied to assess their inhibitory potential on phospholipase from snake venoms and to determine their cytogenotoxic action on human cells. These essential oils were able to inhibit the breakdown of phospholipids induced by venoms of snakes of the Bothrops genus. Both oils presented hemolytic activity, although the Mentha viridis (L). L. oil induced hemolysis only at the highest concentrations (14.6 and 29 μL·mL-1). The essential oil from M. viridis induced 3.9;8.6 and 16.2 times greater damage to human leukocyte DNA than that observed with the positive control (100 μg·μL-1 doxorubicin) at concentrations of 0.25;0.5 and 1.0 μL·mL-1, respectively. A similar effect was observed for the oil from M. pulegium (2.1, 2.5 and 15.8 times greater damage). The results extend the characterization of these essential oils and demonstrate their potential use in industries.

关键词： Essential Oils Mentha viridis(L).L. Mentha pulegium L. Hemolysis comet Assay

“cachacas”(Sugarcane Spirit)Aged Quantitation of Phenolic compounds,Antibacterial and Antioxidant Activity

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American Journal of Plant Sciences 2014年第20期5卷 2935-3942页

作者： Leonardo Milani Avelar Rodrigues maria das gracas cardoso Luís Roberto Batista Wilder Douglas Santiago Juliana maria Valério Resende Juliana de Andrade Santiago Marcos de souza Gomes Milene Aparecida Andrade maria Luisa Teixeira Fabiana Reinis Franca Passamani Department of Food Science Federal University of LavrasLavrasBrazil Department of chemistry Federal University of LavrasLavrasBrazil

The “cacha&ccedila” is currently one of the fastest growing agro-industrial industries in the country as the drink considered as a symbol of Brazilian nationality. This study aimed to quantify the phenolic compounds... 详细信息

The “cachaça” is currently one of the fastest growing agro-industrial industries in the country as the drink considered as a symbol of Brazilian nationality. This study aimed to quantify the phenolic compounds, evaluate the antioxidant and antibacterial activity of different samples of aged “cachaça”. The physic-chemical analysis was performed at the Brandy Quality Laboratory of the Federal University of Lavras, and the determination of phenolic compounds was performed by High Performance Liquid chromatography (HPLc). The antimicrobial activity evaluation was held at the Food Mycology Laboratory through the cavity agar diffusion technique and by steam using the micro-organisms Escherichia coli, Staphylococcus aureus, Salmonella choleraesuis, Listeria monocytogenes and Pseudomonas aeruginosa. The antioxidant activity was evaluated using the DPPH radical sequestering method. The values obtained for the phenolic compounds ranged from 0.41 to 9.69 mg/L, observing the predominance of syringaldehyde, gallic acid and vanillic acid. The phenolic extracts showed a satisfactory antibacterial activity for both Gram-negative and Gram-positive but did not show inhibition against the bacteria Pseudomonas aeruginosa. The antioxidant activity was evidenced by the DPPH test for cachaças tested and the “cachaça” aged in oak barrel showed the highest activity, followed by “cachaça” aged in jequitibá, amburana and balm barrels.

关键词： Syringaldehyde Gallic Acid Vanillic Acid Bacteria DPPH Test

Automatic Detection of cOVID-19 Infection Using chest X-Ray Images Through Transfer Learning

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IEEE/cAA Journal of Automatica Sinica 2021年第1期8卷 239-248页

作者： Elene Firmeza Ohata Gabriel Maia Bezerra João Victor souza das chagas Aloísio Vieira Lira Neto Adriano Bessa Albuquerque Victor Hugo cde Albuquerque Pedro Pedrosa Rebouças Filho the Universidade Federal do ceará FortalezaCE 60455-970and also with the Instituto Federal do CearáFortalezaCE 60040-215Brazil the Instituto Federal do ceará FortalezaCE 60040-215Brazil the Universidade de Fortaleza FortalezaCE 60811-905Brazil

The new coronavirus(cOVID-19),declared by the World Health Organization as a pandemic,has infected more than 1 million people and killed more than 50 *** infection caused by cOVID-19 can develop into pneumonia,which can be detected by a chest X-ray exam and should be treated *** this work,we propose an automatic detection method for cOVID-19 infection based on chest X-ray *** datasets constructed for this study are composed of194 X-ray images of patients diagnosed with coronavirus and 194 X-ray images of healthy *** few images of patients with cOVID-19 are publicly available,we apply the concept of transfer learning for this *** use different architectures of convolutional neural networks(cNNs)trained on Image Net,and adapt them to behave as feature extractors for the X-ray ***,the cNNs are combined with consolidated machine learning methods,such as k-Nearest Neighbor,Bayes,Random Forest,multilayer perceptron(MLP),and support vector machine(SVM).The results show that,for one of the datasets,the extractor-classifier pair with the best performance is the Mobile Net architecture with the SVM classifier using a linear kernel,which achieves an accuracy and an F1-score of 98.5%.For the other dataset,the best pair is Dense Net201 with MLP,achieving an accuracy and an F1-score of 95.6%.Thus,the proposed approach demonstrates efficiency in detecting cOVID-19 in X-ray images.

关键词： convolutional neural networks(cNNs) cOVID-19 transfer learning X-ray

Essential Oils from Mentha piperita,cymbopogon citratus,Rosmarinus officinalis,Peumus boldus and Foeniculum vulgare:Inhibition of Phospholipase A_(2) and cytotoxicity to Human Erythrocytes

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American Journal of Plant Sciences 2017年第9期8卷 2196-2207页

作者： Danubia Aparecida de carvalho Selvati Rezende maria das gracas cardoso Rafaela Vieira souza maria Luisa Teixeira Rafaela Magalhaes Brandao Vanuzia Rodrigues Fernandes Ferreira Jéssica Oliveira e Nogueira Maisa Lamounier Magalhaes Silvana Marcussi David Lee Nelson Departamento de Química Universidade Federal de Lavras Lavras Brasil Departamento de ciência dos Alimentos Universidade Federal de Lavras Lavras Brasil Universidade Federal do Vale do Jequitinhonha e Mucuri Diamantina Brasil

The essential oils from Mentha piperita, cymbopogon citratus, Rosmarinus officinalis, Peumus boldus and Foeniculum vulgare were extracted by hydrodistillation and characterized and quantified by Gc-MS and Gc-DIc. The oils induced hemolysis with all the doses evaluated (0.6 to 1.8 μL), and the diameters of the halos varied between 9 and 15 mm. Pre-incubation of P. boldus oil with Bothrops jararacussu venom resulted in potentiation of venom-induced hemolysis (30%) (proteases and phospholipases A2). The essential oil from M. piperita (0.6 μL) inhibited venom-induced hemolysis by 45%, whereas 0.6 μL of R. officinalis oil increased the hemolysis by 20%. For the essential oil from F. vulgare, 100% inhibition of activity (0.6 and 1.2 μL) was observed. The application of c. citratus oil induced hemolysis with all the volumes evaluated. Phospholipase activity induced by the venom was only inhibited (10%) with the 0.6 μL volume of R. officinalis oil. The oils from M. piperita and F. vulgare (1.8 μL) and c. citratus oil (0.6 μL) potentiated the phospholipase activity. The results highlight the need for a broad characterization and regulation of the use of natural products, because they can have therapeutic or toxic actions.

关键词： Natural Products Snake Venoms Hemolysis Pharmacological Potential