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seasonal testicular changes in Dendropsophus minutus Peters, 1872 (Anura, Hylidae)

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BIOCELL 2012年第2期36卷 57-62页

作者： ADELINA ferreira MAHMOUD MEHANNA Universidade Federal de Mato Grosso(UFMT) Instituto de BiociênciasCuiabáMTBrasil Universidade Estadual Paulista Julio de Mesquita Filho(UNEsP) Laboratório de Biologia de PeixesPós-graduação em ZoologiaBotucatuSPBrasil

The reproductive cycle in anurans may be either continuous or *** differences may be connected to seasonal climate changes and/or to anthropic *** adult male individuals of the Dendropsophus minutus species were collected during one year,in the municipality of Chapada dos Guimarães(Mato Grosso,Brazil).The testicles were studied under light and transmission electron *** variations were observed when the diameter of the seminiferous tubules and the thickness of the interstitial tissue were ***,changes in spermatogenesis were conspicuous and indicated that the reproductive cycle of *** in Chapada dos Guimarães is discontinuous and seems related to variations in air temperature and rainfall.

关键词： spermatogenesis reproduction anura ultrastructure Chapada dos Guimarães

Fluidized and vibrofluidized shallow beds of fresh leaves

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Particuology 2011年第2期9卷 139-147页

作者： Renata de Aquino Brito Lima Maria do Carmo ferreira Drying Center of Pastes Suspensions and SeedsChemical Engineering DepartmentFederal University of S o Carlos

The fluid dynamics behavior of shallow fluidized and vibrofluidized beds operating with fresh leaves was investigated with the aim of exploring drying applications in a modified conveyor belt （MCB） system, which may be operated in a fixed- or fluidized-bed mode. Leaves of the specimens Duranta repens, schinus molle, Coleus barbatus, Buxus sempervirens, and Bougainvillea spectabilis were tested with a range of sphericities from 0.063 to 0.213, bulk densities from 0.038 to 0.251 g/cm3, apparent densities from 0.52 to 0.97 g/cm3 and ratios of total surface area to volume from 21 to 224 cm-1. Fluidization characteristic curves were obtained by measuring pressure drops versus air velocity in a rectangular column of 0.20 m - 0.11 m cross section. It was not possible to reach real fluidized regimes with the leaves due to strongly non-homogeneous beds. Nevertheless, the characteristic curves allowed for the identification of a transition regime from fixed- to expanded-beds, and parameters such as air velocity and pressure drop obtained from the experimental data at the transition were reproducible for specimens with lower surface area or lower specific gravity （i.e., Duranta repens, schinus molle, and Bougainvillea spectabilis）. The transition velocity and pressure drop could not be predicted by the literature developed for estimat- ing minimum fluidization conditions. The use of vibration at dimensionless vibration parameters （Γ） of 0.5 and 1.0 helped to reduce channeling and decrease the transition velocities from fixed to expanded regimes although it did not affect the pressure drops after the bed expansion. The results suggest that drying fresh leaves using the MCB dryer operating in a fluidized mode would not be feasible because none of the materials investigated attained a high-quality fluidization. Operation of the MCB dryer may be pos- sible by alternating between the fixed and vibrofluidized modes. For the specimens tested, the drying should be performed in a range

关键词： LeavesLow-sphericity particlesPressure dropsFluidizationVibration

Distribution and origin of polycyclic aromatic hydrocarbons in surface sediments from an urban river basin at the Metropolitan Region of Curitiba,Brazil

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Journal of Environmental sciences 2011年第6期23卷 904-911页

作者： Natalicio ferreira Leite Patricio Peralta-Zamora Marco Tadeu Grassi Instituto de Tecnologia do Paran(TECPAR) 81350-010 CuritibaBrazil Departamento de Química Universidade Federal do Parana'(UFPR)C.P.1908181531-990 CuritibaBrazil

The concentrations of 16 polycyclic aromatic hydrocarbons（PAHs） were determined in surface sediment samples from nine sites located at the Iguau River Basin in the Metropolitan Region of Curitiba,Brazil to evaluate their distribution and *** total concentration of the PAHs was greater for sediments from highly urbanized areas,while the sediments from the Iraí Environmental Protection Area（Iraí EPA） showed significantly low *** sediments from the Iguau and Barigui rivers were classified as highly contaminated,while those from the Cercado and Curralinho rivers were classified as moderately *** predominance of PAHs containing two to four aromatic rings in most of the samples suggested the direct input of raw sewage into the water resources ***[g,h,i]perylene,dibenzo[a,h]anthracene and indeno[1,2,3-cd]pyrene were predominant in sediments from the areas under the greatest urban and industrial *** correlation between thermodynamic stability and the kinetics of evolution presented by the isomeric pairs indicated that combustion is the predominant source of PAHs in the sediments because the combustion of fossil fuels affected most of the points evaluated,followed by combustion of biomass and eventually combustion of oil product *** general,the results showed that areas under strong urban influence,as well as the Iraí EPA,receive contributions of PAHs from similar sources.

关键词： PAHs trace level analysis fiver sediment isomeric ratio Igua^u River Basin

REVIsITING THE sIMILAR PROCEss TO ENGINEER THE CONTEMPORARY sYsTEMs

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Journal of systems science and systems Engineering 2010年第3期19卷 321-350页

作者： Ana Luísa RAMOs José Vasconcelos ferreira Jaume BARCELó GOVCOPP-Department of Economics Management and Industrial EngineeringUniversity of Aveiro Department of statistics and Operations Research Technical University of Catalonia

This paper addresses the present-day context of systems Engineering, revisiting and setting up an updated framework for the sIMILAR process in order to use it to engineer the contemporary systems. The contemporary world is crowded of large interdisciplinary complex systems made of other systems, personnel, hardware, software, information, processes, and facilities. An integrated holistic approach is crucial to develop these systems and take proper account of their multifaceted nature and numerous interrelationships. As the system＇s complexity and extent grow, the number of parties involved （stakeholders and shareholders） usually also raises, bringing to the interaction a considerable amount of points of view, skills, responsibilities, and interests. The systems Engineering approach aims to tackle the complex and interdisciplinary whole of those socio-technical systems, providing the means to enable their successful realization. Its exploitation in our modern world is assuming an increasing relevance noticeable by emergent standards, academic papers, international conferences, and post-graduate programmes in the field. This work aims to provide ＂the picture＂ of modern systems Engineering, and to update the context of the sIMILAR process model in order to use this renewed framework to engineer the challenging contemporary systems. The emerging trends in the field are also pointed-out with particular reference to the Model-Based systems Engineering approach.

关键词： sIMILAR process systems engineering standards MBsE

THE EFFECT OF MEMORY TERMs IN DIFFUsION PHENOMENA

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Journal of Computational Mathematics 2006年第1期24卷 91-102页

作者： A. Araújo J.A. ferreira P. Oliveira Departamento de Matemática Universidade de Coimbra Portugal

In this paper the effect of integral memory terms in the behavior of diffusion phenomena is studied. The energy functional associated with different models is analyzed and stability inequalities are established. Approximation methods for the computation of the solution of the integro-differential equations are constructed. Numerical results are included.

关键词： Heat propagation Integro-differential equation Numerical approximation,splitting method

Interference of iron as a coagulant on MIB removal by powdered activated carbon adsorption for low turbidity waters

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Journal of Environmental sciences 2013年第8期25卷 1575-1582页

作者： ferreira Filho sIDNEY sECKLER Marchetto MARGARIDA Alves Laganaro ROsEMEIRE Department of Hydraulic and Environmental Engineering Polytechnic School University of Sao Paulo Department of sanitary and Environmental Engineering University of Mato Grosso Companhia de saneamento Basico do Estado de so Paulo(sABEsP)

Powered activated carbon （PAC） is widely used in water treatment plants to minimize odors in drinking water. This study investigated the removal of 2-methylisoborneol （MIB） by PAC adsorption, combined with coagulation using iron as a coagulant. The adsorption and coagulation process were studied through different case scenarios of jar tests. The analysis evaluated the effect of PAC dosing in the liquid phase immediately before or after the coagulant addition. Ferric sulphate was used as the coagulant with dosages from 10 to 30 mg/L, and PAC dosages varied from 10 to 40 mg/L. The highest MIB removal efficiency （about 70%） was achieved without the coagulant addition and with the highest PAC dosage （40 mg/L）. Lower MIB removal efficiencies were observed in the presence of coagulant, showing a clear interference of the iron precipitate or coagulant in the adsorption process. The degree of interference of the coagulation process in the MIB removal was proportional to the ratio of ferric hydroxide mass to the PAC mass. For both cases of PAC dosing, upstream and downstream of the coagulant injection point, the MIB removal efficiency was similar. However, MIB removal efficiency was 15% lower when compared with experiments without the coagulant application. This interference in the MIB adsorption occurs potentially because the coagulant coats the surface of the carbon and interferes with the MIB coming in contact with the carbon＇s surface and pores. This constraint requires an increase of the PAC dosage to provide the same efficiency observed without coagulation.

关键词： adsorption 2-methylisoborneol (MIB) coagulation activated carbon

Using meshes to change the characteristics of simulated rainfall produced by spray nozzles

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International soil and Water Conservation Research 2014年第2期2卷 67-78页

作者： sílvia C.P.Carvalho João L.M.P.de Lima M.Isabel P.de Lima Department of Civil Engineering Faculty of Science and TechnologyUniversity of CoimbraCoimbraPortugal Department of Civil Engineering Campus II-University of CoimbraRua Luís Reis Santos3030-788 CoimbraPortugal

Rainfall simulators have been used for many years contributing to the understanding of soil and water conservation ***,rainfall simulators’design and operation might be rather demanding for achieving specific rainfall intensity distributions and drop characteristics and are still open for *** study explores the potential of combining spray nozzle simulators with meshes to change rainfall characteristics,namely drop properties(drop diameters and fall speeds).A rainfall simulator laboratory set-up was prepared that enabled the incorporation of different wire meshes beneath the spray *** tests conducted in this exploratory work included different types of spray nozzles,mesh materials(plastic and steel),square apertures and wire thicknesses,and positions of the meshes in relation to the *** intensity and drop size distribution and fall speed were *** showed that the meshes combined with nozzles increased the mean rainfall intensity on the 1 m^(2) control plot below the nozzle and altered the rain drops’properties,by increasing the mass-weighted mean drop diameter,for example.

关键词： Rainfall simulators spray nozzle meshes Drop characteristics

Photodynamic therapy in cancer treatment - an update review

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Journal of Cancer Metastasis and Treatment 2019年第3期4卷 131-150页

作者： Ancély ferreira dos santos Daria Raquel Queiroz de Almeida Leticia ferreira Terra Mauricio s.Baptista Leticia Labriola Department of Biochemistry Chemistry InstituteUniversity of São PauloSão Paulo 05508-000Brazil

Cancer remains a worldwide health problem, being the disease with the highest impact on global health. Even with all the recent technological improvements, recurrence and metastasis still are the main cause of death. since photodynamic therapy (PDT) does not compromise other treatment options and presents reduced long-term morbidity when compared with chemotherapy or radiotherapy, it appears as a promising alternative treatment for controlling malignant diseases. In this review, we set out to perform a broad up-date on PDT in cancer research and treatment, discussing how this approach has been applied and what it could add to breast cancer therapy. We covered topics going from the photochemical mechanisms involved, the different cell death mechanisms being triggered by a myriad of photosensitizers up to the more recent-on-going clinical trials.

关键词： Photodynamic therapy breast cancer photosensitizers cell death

sintering of Pellets, Compound by Fly Ash, Clay and Charcoal in a Fixed Bed Combustion Reactor

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Journal of Mechanics Engineering and Automation 2016年第2期6卷 77-84页

作者： Alvino Oliveira melo Emanuel Negrao Macedot Danielly Quaresma lose Antonio da s. souza Alacid Neves Marcio ferreira Martins Department of Mechanical and Materials Federal Institute of Education Science and Technology of Maranh6o S. Luis-Ma65030-005 Brazil Department of Chemical Engineering Federal University of Para Belem PA 66075-110 Brazil Laboratory of Combustion and Combustible Matter (LCCm) Federal University of Espirito Santo Vitoria-ES 29075-910 Brazil

Normally, industries in general, produce waste at its majority toxic, such as fly ash, for example, which damage the environment. The aim of this paper is to investigate the evolution of the temperature in a combustion reactor, full of pellets manufactured with fly ash, clay and charcoal powder, after sintering, to obtainment synthetic aggregates for use in civil construction. The pellets were produced in a cement mix. For realization of the work, a co-current combustion reactor was made in order to analyze the temperatures profile and investigate if the values of these temperatures would be sufficient to initiate the process of sintering of the pellets. Temperatures reached in the reactor varied in the range of 800 ℃-1,290 ℃. These values are sufficient to initiate the process of sintering of the pellets. For the experiment realized, parameters such as inlet velocity of the fluid （air）, diameters of the pellets and size of charcoal crushed in a disk mill were varied and the effect of variations of these parameters were analyzed for the experiment. The historical temperatures were recorded by a data acquisition instrument and subsequently plotted for analysis.

关键词： Combustion reactor charcoal fly ash clay porous media.