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Mitigating adjacent channel interference in vehicular communication systems

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Digital Communications and Networks 2016年第2期2卷 57-64页

作者： Joao Almeida Muhammad Alam Joacluim Ferreira arnaldo s.R. Oliveira lnstituto de Telecomunicar/ses Campus Universitdirio de Santiago 3810-193 Aveiro Portugal DETI - Universidade de Aveiro Campus Universitdrio de Santiago 3810-193 Aveiro Portugal EsTGA - Universidade de Aveiro 3754-909 gueda Portugal

In the last few decades, dedicated wireless channels were specifically allocated to enable the development and implementation of vehicular communication systems. The two main protocol stacks, the WAVE stan- dards proposed by the IEEE in the United states and the ETsI ITs-G5 in Europe, reserved 10 MHz wide channels in the 5.9 GHz spectrum band. Despite the exclusive use of these frequencies for vehicular com- munication purposes, there are still cross channel interference problems that have been widely reported in the literature. In order to mitigate these issues, this paper presents the design of a two-stage FIR low-pass filter, targeting the integration with a digital baseband receiver chain of a custom vehicular communications platform. The filter was tested, evaluated and optimized, with the simulation results proving the effectiveness of the proposed method and the low delay introduced in the overall operation of the receiver chain. 2016 Chongqing University of Posts and Telecommunications. Production and Hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license

关键词： Intelligent transportation systemsVehicular communicationsAdjacent Channel InterferenceFilter designMulti-rate systemsDigital Hardware Design

Bioactive extracts of red seaweeds Pterocladiella capillacea and Osmundaria obtusiloba(Floridophyceae:Rhodophyta) with antioxidant and bacterial agglutination potential

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Asian Pacific Journal of Tropical Medicine 2016年第4期9卷 363-370页

作者： Daniel Barroso de Alencar Fátima Cristiane Teles de Carvalho Rosa Helena Rebouas Daniel Rodrigues dos santos Kelma Maria dos santos Pires-Cavalcante Rebeca Larangeira de Lima Bárbara Mendes Baracho Rayssa Mendes.bezerra Francisco arnaldo Viana Regine Helena silva dos Fernandes Vieira Alexandre Holanda sampaio Oscarina Viana de sousa silvana saker-sampaio Laboratrio de Produtos Naturais Marinhos.Departamento de Engenharia de Pesca Universidade Federal do Ceará.Campus do Pici.Ar.Mister Hull.s/nCaixa Postal 6043 Laboratrio de Microbiologia Ambiental e do Pescado.Instituto de Ciências do Mar.Universidade Federal do Ceará.Av.da Abolicao 3207 Laboratrio de Microbiologia Ambiental e do Pescado.Instituto de Ciências do Mar.Universidade Federal do Ceará Laboratrio de Produtos Naturais Marinhos.Departamento de Engenharia de Pesca Universidade Federal do Ceará Laboratrio de Cromatografia Departamento de QuimicaUniversidade do Estado do Rio Grande do NorteCampus Universitário Central

Objective:To evaluate the antioxidant,antibacterial and bacterial cell agglutination activities of the hexane(Hex) and 70%ethanol(70%EtOH) extracts of two species of red seaweeds Pterocladiella capillacea(***) and Osmundaria ***:In vitro antioxidant activity was determined by DPPH radical scavenging assay,ferric-reducing antioxidant power assay,ferrous ion chelating assay,β-carotene bleaching assay and total phenolic content *** activity was tested using the method of disc diffusion on Mueller-Hinton *** ability of algal extracts to agglutinate bacterial cells was also ***:The 70%EtOH extract of the two algae showed the highest values of total phenolic content compared to the Hex *** results of DPPH for both extracts(Hex,70%EtOH) of Osmundaria obtusiloba(43.46%and 99.47%) were higher than those of ***(33.04%and 40.81%) at a concentration of 1 000 μg/*** for the ferrous ion chelating,there was an opposite behavior,extracts of *** had a higher *** extracts showed a low ferric-reducing antioxidant power,with optical density ranging from0.054 to *** activities of all extracts evaluated for β-carotene bleaching were above 40%.There was no antibacterial activity against bacterial strains ***,the extracts of both species were able to agglutinate bacterial Gram positive cells of staphylococcus aureus and Gram negative cells of Escherichia coli,multidrug-resistant salmonella and Vibrio *** This is the first report of the interaction between these algal extracts,rich in natural compounds with antioxidant potential,and Gram positive and Gram negative bacterial cells.

关键词： Bioactive compounds Antioxidant Bacterial agglutination Rhodophyta

Effect of sewage sludge and sugarcane bagasse biochar on soil properties and sugar beet production

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Pedosphere 2021年第4期31卷 572-582页

作者： Barbara samartini Queiroz ALVEs Katherin Prissila sevilla ZELAYA Fernando COLEN Ledivan Almeida FRAZÃO Alfredo NAPOLI sanjai J.PARIKH Luiz arnaldo FERNANDEs Department of Land Air and Water ResourcesUniversity of California-DavisDavis CA 95616(USA) Institute of Agrarian sciences Federal University of Minas GeraisMontes Claros MG 39404547(Brazil) Department of performance of tropical production and processing systems(PERsYsT) Centre de Coopération Internationale en Recherche Agronomique pour le Développement(CIRAD)Montpellier 34170(France)

Recently, biochar has shown to be an alternative to waste disposal and a source of nutrients, acting as a soil amendment. The effects of two types of biochar on soil properties and sugar beet production as well as potential for carbon(C) sequestration were evaluated: biochar produced from sewage sludge(sB) and biochar produced from a 1:1 mixture of sewage sludge and sugarcane bagasse(MB). A greenhouse pot experiment was conducted using a sandy loam soil from the Brazilian savanna under treatments of MB applications at 2.5%, 5.0%, 7.5%, and 10.0%, sB application at 5.0%, and a conventional fertilization(CF) using lime and mineral fertilizers, with no fertilization as a control. After incubation for 45 d, seedlings were transplanted into each pot and cultivated for 55 d. Biochar characterization showed that pyrolysis reduced the biomass volume drastically, but concentrated the trace elements per unit of biochar weight. The MB treatments increased soil total C(by 27.8%) and pH(by 0.6), reduced the concentrations of nutrients, except for potassium(K), and chromium(Cr), and did not significantly alter lead(Pb) and cadmium(Cd) concentrations. Results of stable isotopes showed that all biochar treatments increased the total soil C stock and stability, suggesting a potential for application in C sequestration, and improved overall soil fertility. However, the biochar treatments also increased the concentrations of trace elements in the soil and plants. The sugar beet yields at 10.0% MB and 5.0% sB corresponded to 55%and 29% of the yield obtained in the CF treatment, respectively. These results may be due to biochar nutrients not being bioavailable when required by plants or to biochar nutrient adsorption.

关键词： carbon sequestration food safety organic wastes plant fertilizers soil fertility soil organic matter fractions stable isotopes waste management

Determination of Hypoxanthine in the Presence of Copper by Adsorptive stripping Voltammetry

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American Journal of Analytical Chemistry 2014年第5期5卷 291-300页

作者： Percio Augusto Mardini Farias arnaldo Aguiar Castro Department of Chemistry Pontifícia Universidade Católica Rua Marquês de S&atilde o Vicente Rio de Janeiro Brazil Facultad Quimica Quimica Analitica Universidad de La Habana Havana Cuba

A stripping method for the determination of hypoxanthine in the presence of copper at the submicromolar concentration levels is described. The method is based on controlled adsorptive accumulation of hypoxanthine-copper at the thin-film mercury electrode followed by a fast linear scan voltammetric measurement of the surface species. Optimum experimental conditions were found to be the use of 1.0 × 10﹣3 mol·L﹣1 NaOH solution as electrolyte supporting, an accumulation potential of ﹣0.50 V and a linear scan rate of 200 mV·s﹣1. The response of hypoxanthine-copper is linear over the concentration ranges of 10 - 60 ppb. For an accumulation time of 30 minutes, the detection limit was found to be 250 ppt (1.8 × 10﹣9 mol·L﹣1). Adequate conditions for measuring the hypoxanthine in the presence of metal ions, xanthine, uric acid and other nitrogenated bases were also investigated. The utility of the method is demonstrated by the presence of hypoxanthine associated in ATP or ssDNA.

关键词： Hypoxanthine Determination Xanthine Uric Acid Copper Ion ATP ssDNA Thin-Film Mercury Electrode Fast Linear scan stripping Voltammetry

Photonic smart bandage for wound healing assessment

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Photonics Research 2021年第3期9卷 272-280页

作者： arnaldo Leal-Junior Jingjing Guo Rui Min Antonio Jose Fernandes Anselmo Frizera Carlos Marques Telecommunications Laboratory(LABTEL) Graduate Program in Electrical EngineeringFederal University of Espi’rito SantoVitoria-ES 29075-910Brazil school of Instrumentation and Optoelectronic Engineering Beihang UniversityBeijing 100191China Center for Cognition and Neuroergonomics State Key Laboratory of Cognitive Neuroscience and LearningBeijing Normal UniversityZhuhai 519087China Physics Department&I3N Universidade de AveiroCampus Universitario de SantiagoAveiro 3810-193Portugal

Chronic wounds affect around 2% of the world population with an annual multi-billion dollar cost to the healthcare system. This background pushes the development of new therapies and procedures for wound healing and its assessment. Among them, the potential of hydrogen(pH) assessment is an important indicator of the wound healing stage and condition. This paper presents the development of the first optical fiber-embedded smart wound dressing for pH assessment. An intrinsically pH-sensitive optical fiber is fabricated using a polydimethylsiloxane(PDMs) precursor doped with rhodamine B dye. Raman and Fourier transform infrared(FTIR) spectroscopies are performed in order to verify the presence of rhodamine B and PDMs in the fiber samples. Then, the fiber is embedded in gauze fabric and hydrocolloid wound dressing. In addition, such low Young’s modulus of PDMs fiber enables its use as a highly sensitive pressure sensor, where the results show that the fiber-embedded bandage can measure pressures as low as 0.1 kPa with a high linearity in the range of 0 to 0.3 kPa. The smart bandage is subjected to different pH, which resulted in a wavelength shift of 0.67 nm/pH when the absorption peak at 515 nm was analyzed. Furthermore, pH increase leads to linear decrease of the transmitted optical power(R2 of 0.998), with rise and fall times below 20 s and 30 s, respectively. Therefore, the proposed optical fiber-embedded smart bandage enables the simultaneous assessment of pressure and pH on the wound region.

关键词： fiber smart healing

Association of nonalcoholic fatty liver disease and liver cancer

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World Journal of Gastroenterology 2015年第3期21卷 913-918页

作者： Perla Oliveira schulz Fabio Goncalves Ferreira Maria de Fátima Araújo Nascimento Andrea Vieira Mauricio Alves Ribeiro André Ibrahim David Luiz arnaldo szutan Gastroenterology service Internal Medicine DepartmentSanta Casa School of Medical SciencesSao Paulo 01277-900Brazil Department of surgery Liver and Portal Hypertension GroupSanta Casa School of Medical SciencesSao Paulo 01277-900Brazil Pathology Department Santa Casa School of Medical SciencesSao Paulo 01277-900Brazil GI Transplant service Gastroenterology DepartmentUniversity of Sao PauloSao Paulo 01246-903Brazil

AIM:To investigate the association between nonalcoholic fatty liver disease(NAFLD) and liver cancer,and NAFLD prevalence in different liver ***:This is a retrospective study of the clinical,laboratory and histological data of 120 patients diagnosed with primary or secondary hepatic neoplasms and treated at a tertiary center where they underwent hepatic resection and/or liver transplantation,with subsequent evaluation of the explant or liver *** following criteria were used to exclude patients from the study:a history of alcohol abuse,hepatitis B or C infection,no tumor detected in the liver tissue examined by histological analysis,and the presence of chronic autoimmune hepatitis,hemochromatosis,Wilson's disease,or *** occurrence of NAFLD and the association with its known risk factors were *** risk factors considered were diabetes mellitus,impaired glucose tolerance,impaired fasting glucose,body mass index,dyslipidemia,and arterial *** of reticulin fibers in the hepatic neoplasms was assessed by histological analysis using slide-mounted specimens stained with either hematoxylin and eosin or Masson's trichrome and silver *** of tumor-free liver parenchyma was carried out to determine the association between NAFLD and its histological ***:No difference was found in the association of NAFLD with the general population(34.2% and 30.0% respectively,95%CI:25.8-43.4).Evaluation by cancer type showed that NAFLD was more prevalent in patients with liver metastasis of colorectal cancer than in patients with hepatocellular carcinoma and intrahepatic cholangiocarcinoma(OR = 3.99,95%CI:1.78-8.94,P s OR = 0.60,95%CI:0.18-2.01,P = 0.406 and OR = 0.70,95%CI:0.18-2.80,P = 0.613,respectively).There was a higher prevalence of liver fibrosis in patients with hepatocellular carcinoma(OR = 3.50,95%CI:1.06-11.57,P = 0.032).Evaluation of the relationship between the presence of NAFLD,nonalcoholi

关键词： Hepatocellular carcinoma Colorectal liver metastases Intrahepatic cholangiocarcinoma Liver fibrosis Nonalcoholic fatty liver disease Nonalcoholic steatohepatitis

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

Diversity of the endophytic filamentous fungal leaf community at different development stages of eucalyptus

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Journal of Forestry Research 2019年第3期30卷 1093-1103页

作者： Paulo sergio Balbino Miguel Fabio Balbino Miguel Bruno Coutinho Moreira Marcelo Nagem Valerio de Oliveira Julio Cesar Delvaux Fernanda de souza Freitas arnaldo Chaer Borges Maurcio Dutra Costa Departamento de Medicina e Enfermagem Universidade Federal de VicosaVicosaMinas Gerais 36570-000Brazil Departamento de Quimica Universidade Federal de Juiz de ForaJuiz de ForaMinas Gerais 36036-300Brazil Colegiado de Engenharia Agronomica Universidade Federal do Vale do Sao FranciscoPetrolinaPernambuco 56300-990 Brazil Departamento de Ciencias Basicas da Vida Campus Governador Valadares Universidade Federal de Juiz de Fora Governador ValadaresMinas Gerais 35012-140Brazil Coordenacao Geral de Ensino Pesquisa e Extensao Instituto Federal do Triangulo MineiroItuiutabaMinas Gerais 38035-200Brazil Departamento de Microbiologia Instituto de Biotecnologia Aplicada aAgropecuariaUniversidade Federal de Vicosa VicosaMinas Gerais 36570-000Brazil

Fungal endophytic species inhabiting the leaves of eucalypts are capable of utilising leaf sugars and can influence both plant growth and health. Endophytic fungal symbionts can use simple soluble sugars in leaves as their main carbon source. This study set out to determine the diversity and distribution of the endophytic filamentous fungal leaf community in the hybrid Eucalyptus urograndis due to its economic importance. The fungal leaf community was characterised using denaturing gradient electrophoresis (DGGE) and correlated with levels of leaf nutrients and sugars throughout plant development. sequencing of DGGE bands revealed the presence of Basidiomycota and Ascomycota phyla. Fourteen species and three genera of filamentous fungi were identified, and the population structure was affected by the plant developmental stage. Levels of K, Cu, N and Mn influenced communities from the clonal garden, whereas leaves in the field had higher glucose, fructose and sucrose. Many fungi were found to be specific to a certain development stages: Diplomitoporus crustulinus, Podosphaera tridactyla and Aspergillus restrictus to the clonal garden stage;Chaetomella acutiseta and Ascotricha chartarum to the shading stage;Erratomyces patelii and saxomyces sp. to the shading output stage;Lepidostroma sp. and saxomyces sp. to the dispatch stage;and Mycosphaerella populicola to the field stage. Teratosphaeria toledana and Teratosphaeria acidotherma were found at more than one developmental stage. Cladosporium sp. and Rhodosporidium fluviale colonized and persisted in plants at the dispatch and field stages. This is the first report of P. tridactyla, A. restrictus, E. patelii, saxomyces and Lepidostroma sp. as endophytes in eucalipt.

关键词： Diversity 18s rRNA Denaturing gradient electrophoresis(DGGE) sequencing

Determination of the Antiretroviral Drug Zidovudine in Diluted Alkaline Electrolyte by Adsorptive stripping Voltammetry at the Mercury Film Electrode

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American Journal of Analytical Chemistry 2011年第2期2卷 223-234页

作者： arnaldo Aguiar Castro Ricardo Queiroz Aucélio Nicolás Adrián Rey Eliane Monsores Miguel Percio Augusto Mardini Farias 不详

This paper describes a stripping method for the determination of zidovudine at the submicromolar concentration levels. This method is based on the controlled adsorptive accumulation of zidovudine at the thin-film mercury electrode, followed by a linear-sweep stripping voltammetry measurement of the surface species. Optimal experimental conditions include a NaOH solution of 2.0 × 10–3 mol●L–1 (sup-porting electrolyte), an accumulation potential of –0.30 V and a scan rate of 100 mV?s–1. The response of zidovudine is linear over the concentration range 0.01 - 0.08 ppm. After an accumulation time of 5 minutes, the detection limit was found to be 0.67 ppb (2.5 × 10–9 mol●L–1). More convenient methods to measure zidovudine concentration in the presence of the didanosine, acyclovir, nevirapine, lamivudine, and efavirenz, were also investigated. The presence of zidovudine together with ATP or ssDNA demonstrates the utility of this method.

关键词： Zidovudine Determination Antiviral Drugs ssdna Thin-Film Mercury Electrode stripping Voltammetry