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Journal of Advanced Ceramics 2019年第2期8卷 238-246页

作者： Evando S.ARAuJO Victor N.S.LEAO Research Group on Electrospinning and Nanotechnology Applications(GPEA-Nano) Department of Materials ScienceUniversidade Federal do Vale do Sao Francisco

Relative humidity(RH) is a critical environmental variable for transportation and storage of products and for the quality guarantee of several other production processes and services. Heterogeneous structures prepared from the selective semiconductor oxides may improve the sensitivity to humidity due to the better electronic and surface properties, when compared to pristine oxides. This work shows an alternative fabrication route for producing titanium dioxide/tungsten trioxide(TiO2/WO3) heterogeneous structures(by electrospinning and sintering) for potential application on the RH detection. The microstructural properties of the materials were analyzed by scanning electron microscopy(SEM), energy dispersive X-ray analysis(EDS), X-ray diffraction, and Raman spectroscopy. The electrical characterization of the structures was performed by electrical impedance spectroscopy in RH range of 10%–100%. Results indicated a p-to n-type conduction transition at around 30%–40% RH for all tested settings. The analysis of the impedance signature to humidity showed that the amount of fiber layers on the electrode and working temperature are important parameters to improve the humidity sensing of the TiO2/WO3 systems.

关键词： electrospinning heterogeneous structures preparation relative humidity semiconductors

LC–MS characterization, anti-kinetoplastide and cytotoxic activities of natural products from Eugenia jambolana Lam. and Eugenia uniflora

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Asian Pacific Journal of Tropical Biomedicine 2017年第9期7卷 836-841页

作者： Celestina Elba Sobral de Souza Ana Raquel Pereira da Silva Janaina Esmeraldo Rocha Maria Celeste Vega Gomez Míriam Rolóm Cathia Coronel José Galberto Martins da Costa Manoel L.C.Netto Larissa A.Rolim Henrique douglas Melo Coutinho Laboratório de Microbiologia e Biologia Molecular Universidade Regional do Cariri Center for the Development of Scientific Research Moisés Bertoni Foundation/Díaz Gill Laboratories Laboratório de Pesquisa de Produtos Naturais Universidade Regional do Cariri Centro Universitário Dr.Leao Sampaio–UNILEAO universidade federal do vale do sao francisco–univasf

Objective: To evaluate the trypanocidal, leishmanicidal and cytotoxic activity of Eugenia jambolana(E. jambolana) and Eugenia uniflora(E. uniflora) extracts and ***: The products were characterized by LC–MS. Antiparasitic assays were performed and cytotoxicity was evaluated in fibroblastos. In vitro assays were performed using spectrophotometric evaluation. All assays were performed in ***: The results showed that the extracts and the tannic fraction from E. jambolana inhibited 100% of the epimastigote lines. The ethanolic extract was the most efficient in all concentrations tested against the three parasite strains. In the cytotoxicity assay the flavonoid fraction showed low toxicity. All E. uniflora samples showed cytotoxicity at the highest concentration tested, but the extract showed no toxic effect on the fibroblasts at the lowest concentration. The flavonoid and tannic fractions were more efficient against Leishmania braziliensis promastigotes compared to the extract. However, the extracts and the tannic fraction were more effective against Leishmania infantum strains. The effect on epimastigote cells was observed at all concentrations tested, with all E. uniflora samples. However, the samples were more effective at the highest concentration, where there was inhibition in 100% of the Trypanosoma cruzi ***: The species E. jambolana and E. uniflora presented antiparasitic activity against all tested parasite strains, indicating that these species can serve as an alternative therapy as they were efficient in the tests performed. The E. uniflora extract and the E. jambolana flavonoid fraction presented a low cytotoxicity, opening the floor for new biological studies.

关键词： Antiparasitic effect Cytotoxicity Eugenia jambolana Eugenia uniflora

Carbon dots-doped Electrospun Fibers for Simultaneous Metal Ion Detection and Adsorption of Dyes

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Advanced Fiber Materials 2020年第6期2卷 302-313页

作者： Mário César A.de Oliveira Elisângela G.de L.Oliveira Indira C.B.Pires Iuri C.M.Candido Nikifor Rakov Helinando P.de Oliveira Yutao Xing Glauco S.Maciel Institute of Materials Science Universidade Federal do Vale do São FranciscoJuazeiroBA 48920-310Brazil Instituto de Física Universidade Federal FluminenseNiteróiRJ 24210-346Brazil

The required treatment and monitoring of contaminants in wastewater reinforces the development of low-cost adsorbents/chemosensors,introducing advantages relative to the detection/removal of toxic metals and ***,it is reported a two-step process of fabrication of fluorescent carbon dots via the hydrothermal treatment of amino acids for the following encapsulation in electrospun *** prominent anionic behavior of electrospun fibers of Eudragit L100 was explored for adsorption of cationic dyes(methylene blue and crystal violet)-with the prevailing electrostatic interaction of parts being favored by the formation of monolayers on the surface of *** the other hand,the controlled release of carbon dots(CDs)from fibers to the reactor can be explored for a second application:the nitrogen ligands from released glycine-based carbon dots can be explored to indicate the presence of metal ions in aqueous *** experiment resulted in a quenching in the fluorescence of the CDs in order of 90%in the emission of particles in the response of the presence of Fe^(3+) ions,characterizing a promising perspective for this experimental system.

关键词： Fluorescence Ferric ion detection Electrospinning Carbon nanostructure

Fern extracts potentiate fluconazole activity and inhibit morphological changes in Candida species

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Asian Pacific Journal of Tropical Biomedicine 2017年第11期7卷 1025-1030页

作者： Maria A.Freitas Antonia T.L.Santos Antonio J.T.Machado Ana Raquel P.Silva Fábia F.Campina Maria S.Costa Gioconda M.A.B.Martins Maria Flaviana B.Morais-Braga Saulo R.Tintino Irwin R.A.Menezes Jaime Ribeiro-Filho Altevir P.Medeiros Adeliana S.Oliveira Patrício B.Maracajá Henrique D.M.Coutinho universidade Regional do Cariri-URCA universidade federal Rural do Semi-A′rido-UFERSA universidade federal do Rio Grande do Norte-UFRN universidade federal de Campina Grande-UFCG

Objective: To investigate the antifungal activity of the fern species Lygodium venustum(L. venustum) and Pityrogramma calomelanos(P. calomelanos) against Candida albicans and Candida tropicalis ***: The microdilution method was used to evaluate the antifungal activity, as well as the modulating effects of ethanolic extracts of these plants in combination with fluconazole. The minimum inhibitory concentration(MIC), minimum fungicide concentration and morphological changes were also ***: The extract obtained from L. venustum presented a MIC > 8 192 mg/m L, while the extract obtained from and P. calomelanos presented a MIC = 8 192 mg/m L, indicating that they present weak antifungal activity. However, combination of the extracts with Fluconazole potentiated the antifungal activity of this drug. At different experimental conditions, such as concentration of the extract and type of strain, the extracts inhibited hyphae and pseudohyphae formation, indicating that these fern species can affect the morphology of the ***: The extracts obtained from the fern species L. venustum and P. calomelanos dose not present significant antifungal activity. However, P. calomelanos potentiates the activity of fluconazole and both extracts inhibits the morphological changes in Candida species, indicating that they have potential pharmacological activity as modulators of fungal biology. Therefore, novel studies are required to characterize the interference of these extracts in the virulence and pathogenicity of Candida species as well as the potential of fern species to treat fungal infections.

关键词： Dimorphism Candida species Ferns Lygodium venustum Pityrogramma calomelanos

Congenital Diaphragmatic Hernia with Delayed Diagnosis: Report of Two Cases

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Case Reports in Clinical Medicine 2015年第3期4卷 114-118页

作者： Sidney Pereira Pinto Lemos Patrícia Veruska Ribeiro Barbosa Lemos Natália Araújo Lima Rocha Coelho Danielle Moreira de Abrêu Lucas Barbosa Ribeiro Feitosa Pediatric Surgery Integrative Medicine Institute Fernando Figueira/College of Medicine Universidade Federal do Vale do Sao Francisco. UNIVASF Campus Petrolina. Av. Joséde SáManicoba S/NCenter Petrolina Brasil Gynecology and Obstetrics College of Medicine Universidade Federal do Vale do Sao Francisco (UNIVASF) Petrolina Brasil universidade federal do vale do sao francisco (univasf) Petrolina Brasil universidade federal de Pernambuco Recife Brasil

Introduction: Advances in prenatal imaging studies have allowed early diagnosis of Congenital Diaphragmatic Hernia (CDH), although neonatal mortality remains at high levels (60% survival). Despite advances, this study found delayed diagnosis, demonstrating subdiagnosis, possibly caused by lack of resources and/or prenatal diagnostic failure. Case Report 1: Infant, 4 months and 22 days old, dyspneic, cyanotic, with fever and vomiting for 3 days, treated as pneumonia. After the second chest radiography, a right CDH was revealed. Surgical correction was performed and removal of Meckel’s diverticulum was surgical findings. The patient was discharged on the 10th days after admission. Case Report 2: Infant, 11 months and 3 days old, distended abdomen, with fever and dyspnea for 2 days, treated as pneumonia. After the second chest radiography, a left CDH was revealed. The patient was submitted to surgery, intestinal loop incarceration without necrosis was observed, and the correction of CDH was performed. The patient was discharged on the 7th day after admission. Discussion: Three cases, between July 2012 and July 2013, were diagnosed at dom Malam Hospital;2 Cases of CDH, with delayed diagnosis, showed incidence of 66.66%. Delayed diagnosis of these patients with initial hypotheses of pneumonia demonstrated high risk, emphasizing the importance of diagnosis research through observation of the clinical course, the correct imaging interpretation, in order to establish early diagnosis and treatment.

关键词： Diaphragmatic Hernia Diaphragm Bochdalek

New patterns of the tree beta diversity and its determinants in the largest savanna and wetland biomes of South America

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Plant Diversity 2023年第4期45卷 369-384页

作者： Karla J.P.Silva-Souza Maíra G.Pivato Vinícius C.Silva Ricardo F.Haidar Alexandre F.Souza Departamento de Ecologia Universidade Federal do Rio Grande do NorteRNBrazil Curso de Engenharia Ambiental Universidade Federal do TocantinsTOBrazil

Clear and data-driven bioregionalizations can provide a framework to test hypotheses and base biodiversity *** we used occurrence and abundance data in combination with objective analytical methods to propose two bioregionalization schemes for tree species of the Cerrado and the Pantanal in South *** also evaluated the contribution of three sets of determinants of the occurrence-and abundance-based *** compiled data on tree species composition from 894 local assemblages based on species occurrences,and from 658 local assemblages based on species *** used an unconstrained community-level modelling approach and clustering techniques to identify and map tree subregions for the occurrence and the abundance data sets,*** clustering analyses were conducted to investigate floristic affinities between the subregions and to map broader floristic *** used multinomial logistic regression models,deviance partitioning,and rank-sum tests to assess the main subregion *** identified 18 occurrence-and four abundance-based subregions in the *** hierarchical classifications grouped the occurrence-based subregions into nine floristic zones and abundance-based subregions into two broad floristic *** in subregions were explained mainly by environmental factors and spatial structure in both occurrence and abundance data *** occurrence-and abundance-based subregions are complementary approaches to disentangle macroecological patterns and to plan conservation efforts in the Cerrado and the *** findings based on occurrence data revealed more complex and interdigitated boundaries between subregions of tree species than previously *** environment,historical stability,and human effects act in a synergetic way on the distribution of the ***,the relevance of contemporary environmental factors to the subregion patterns we found alert us to the profound im

关键词： Cerrado Pantanal Savanna Biogeographical regionalization Biodiversity hotspot South America

N-acetylcysteine modulates angiogenesis and vasodilation in stomach such as DNA damage in blood of portal hypertensive rats

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World Journal of Gastroenterology 2015年第43期21卷 12351-12360页

作者： Francielli Licks Renata Minuzzo Hartmann Camila Marques Elizangela Schemitt Josieli Raskopf Colares Mariana do Couto Soares Juliana Reys Camila Fisher Juliana da Silva Norma Possa Marroni universidade federal do Rio Grande do Sul Instituto de Tecnologia do Paraná universidade Luterana do Brasil

AIM: To evaluate the antioxidant effect of N-acetylcysteine(NAC) on the stomach of rats with portal ***: Twenty-four male Wistar rats weighing ± 250 g were divided into four experimental groups(n =6 each): Sham-operated(SO),SO + NAC,partial portal vein ligation(PPVL),and PPVL + NAC. Treatment with NAC in a dose of 10 mg/kg(i.p.) diluted in 0.6 m L of saline solution was administered daily for 7 d starting 8 d after the surgery. Animals from the PPVL and SO group received saline solution(0.6 m L) for the same period of time as the PPVL + NAC and SO + NAC group. On the 15 th day the animals were anesthetized and we evaluated portal pressure by cannulating mesenteric artery. After,we removed the stomach for further analysis. We performed immunohistochemical analysis for endothelial nitric oxide synthase(e NOS),vascular endothelial growth factor(VEGF),and nitrotirosine(NTT) proteins in stomach. We also evaluated e NOS and VEGF by Western blot analysis and assessed DNA damage in blood samples by the comet ***: The portal hypertension group exhibited increases in portal pressure when compared to SO group(29.8 ± 1.8 vs 12.0 ± 0.3 mm Hg)(P < 0.001). The same was observed when we compared the e NOS(56.8 ± 3.7 vs 13.46 ± 2.8 pixels)(P < 0.001),VEGF(34.9 ± 4.7 vs 17.46 ± 2.6 pixels)(P < 0.05),and NTT(39.01 ± 4.0 vs 12.77 ± 2.3 pixels)(P < 0.05) expression by immunohistochemistry of the PPVL animals with the SO group. The expression of e NOS(0.39 ± 0.03 vs 0.25 ± 0.03 a.μ)(P < 0.01) and VEGF(0.38 ± 0.04 vs 0.26 ± 0.04 a.μ)(P < 0.01) were also evaluated by Western blot analysis,and we observed an increase of both proteins on PPVL animals. We also evaluated the DNA damage by comet assay,and observed an increase on damage index and damage frequency on those animals. NAC decreased portal pressure values in PPVL + NAC animals(16.46 ± 2 vs 29.8 ± 1.8 mm Hg)(P < 0.001) when compared to PPVL. The expression of e NOS(14.60 ± 4.1 vs 56.8 ± 3.7 pixels)(P < 0.001

关键词： N-Acetylcysteine Portal hypertension Gastropathy Oxidative stress Antioxidant

PREDICTION OF VORTEX-INDUCED VIBRATION OF LONG FLEXIBLE CYLINDERS MODELED BY A COUPLED NONLINEAR OSCILLATOR:INTEGRAL TRANSFORM SOLUTION

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Journal of Hydrodynamics 2012年第6期24卷 888-898页

作者： GU Ji-jun AN Chen LEVI Carlos SU Jian Ocean Engineering Program COPPEUniversidade Federal do Rio de Janeiro Nuclear Engineering Program COPPEUniversidade Federal do Rio de Janeiro

The Generalized Integral Transform Technique （GITT） was applied to predict dynamic response of Vortex-Induced Vibration （VIV） of a long flexible cylinder. A nonlinear wake oscillator model was used to represent the cross-flow force acting on the cylinder, leading to a coupled system of second-order Partial Differential Equations （PDEs） in temporal variable. The GITT approach was used to transform the system of PDEs to a system of Ordinary Differential Equations （ODEs）, which was numerically solved by using the Adams-Moulton and Gear method （DIVPAG） developed by the International Mathematics and Statistics Library （IMSL）. Numerical results were presented for comparison to those given by the finite difference method and experimental results, allowing a critical evaluation of the technique performance. The influence of variation of mean axial tension induced by elongation of flexible cylinder was evaluated, which was shown to be not negligible in numerical simulation of VIV of a long flexible cylinder.

关键词： Vortex-Induced Vibration (VIV) nonlinear wake oscillator flexible cylinder integral transform

Null Controllability of Some Reaction-Diffusion Systems with Only One Control Force in Moving domains

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Chinese Annals of Mathematics,Series B 2016年第1期37卷 29-52页

作者： J. LIMACO M. CLARK A. MARINHO S. B. de MENEZES A. T. LOUREdo universidade federal Fluminense IM RJ Brazil universidade federal do Piaui DM PI Brazil universidade federal do Piaui DM PI Brazil universidade federal do Ceara DM CE Brazil universidade Estadual da Pavaiba DM PB Brazil.

In this article, the authors establish the local null controllability property for semilinear parabolic systems in a domain whose boundary moves in time by a single control force acting on a prescribed subdomain. The proof is based on Kakutani＇s fixed point theorem combined with observability estimates for the associated lineaxized system.

关键词： Kakutani's fixed point theorem Unique continuation Null controllability

Gain of transcription factor binding sites is associated to changes in the expression signature of human brain and testis and is correlated to genes with higher expression breadth

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Science China(Life Sciences) 2019年第4期62卷 526-534页

作者： Vandeclécio Lira da Silva André Mauricio Ribeiro dos Santos Wilfredo Blanco Sandro José de Souza Bioinformatics Multidisciplinary Environment (BioME) Universidade Federal do Rio Grande do Norte (UFRN) Programa de Pós-Gradua??o em Genética e Biologia Molecular (PPGBM) Universidade Federal do Pará (UFPA) Department of Computer Science Universidade Estadual do Rio Grande do Norte (UERN) Brain Institute Universidade Federal do Rio Grande do Norte (UFRN)

The gain of transcription factor binding sites(TFBS) is believed to represent one of the major causes of biological *** we used strategies based on comparative genomics to identify 21,822 TFBS specific to the human lineage(TFBS-HS),when compared to chimpanzee and gorilla genomes. More than 40%(9,206) of these TFBS-HS are in the vicinity of 1,283 genes.A comparison of the expression pattern of these genes and the corresponding orthologs in chimpanzee and gorilla identified genes differentially expressed in human tissues. These genes show a more divergent expression pattern in the human testis and brain, suggesting a role for positive selection in the fixation of TFBS gains. Genes associated with TFBS-HS were enriched in gene ontology categories related to transcriptional regulation, signaling, differentiation/development and nervous ***, genes associated with TFBS-HS present a higher expression breadth when compared to genes in general. This biased distribution is due to a preferential gain of TFBS in genes with higher expression breadth rather than a shift in the expression pattern after the gain of TFBS.

关键词： TFBS transcript factor human evolution expression breadth