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Physical habitat condition as a key tool to maintain freshwater biodiversity in neotropical artificial ponds

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Water Biology and Security 2023年第3期2卷 30-35页

作者： Marden S.Linares Livia B.dos santos Marcos callisto Jean c.santos Universidade Federal de Minas Gerais Instituto de Ciencias BiologicasDepartamento de GeneticaEcologia e EvoluçaoLaboratorio de Ecologia de BentosAv.Antonio Carlos 6627CEP 31270-901PampulhaBelo HorizonteMGBrazil Laboratorio de Macroecologia e conservaçao da Biodiversidade Departamento de Botanica e EcologiaUniversidade Federal do Mato GrossoAv.Fernando Correa da Costa2367Boa EsperançaCuiabaMato GrossoCEP 78060-900Brazil Programa de Pos-Graduaçao em ciencias Ambientais Instituto de Ciencias NaturaisHumanas e SociaisUniversidade Federal do Mato GrossoAvenida Alexandre Ferronato1200SinopMTCEP 78550-728Brazil Universidade Federal de Sergipe Departamento de EcologiaCampus Sao Cristovao-Cidade Universitaria Prof.Jose Aloísio de CamposCEP 49100-000Sao CristovaoSergipeBrazil

In areas highly affected by anthropogenic disturbances,artificial(human-made)freshwater ecosystems can provide habitat for maintaining and conserving regional freshwater *** assessed how the physical habitat of artificial ponds affected the structure of benthic macroinvertebrate *** do so,we tested two hypotheses.(1)Physical habitat disturbances are not detrimental to the diversity of nearby artificial ponds,and(2)Physical habitat disturbances do not cause significant shifts in taxonomic *** results rejected both null hypotheses,i.e.,macroinvertebrate diversity metrics correlated significantly and positively with Physical Habitat Integrity index scores,and only sites with high habitat condition scores were significantly associated with sensitive indicator *** results highlight the importance of maintaining physical habitat conditions for sustaining the ecological health of artificial ponds.

关键词： Bioindicators Ecosystem management Lentic ecosystems

Exact computation of the Topology and Geometric Invariants of the Voronoi Diagram of Spheres in 3D

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Journal of computer Science & Technology 2013年第2期28卷 255-266页

作者： Franois Anton Darka Mioc marcelo santos Research Division of Geodesy National Space Institute Technical University of Denmark Department of Geodesy and Geomatics Engineering University of New Brunswick

In this paper, we are addressing the exact the Voronoi diagram of spheres using Wu＇s algorithm. computation of the Delaunay graph （or quasi-triangulation） and Our main contributions are first a methodology for automated derivation of invariants of the Delaunay empty circumsphere predicate for spheres and the Voronoi vertex of four spheres, then the application of this methodology to get all geometrical invariants that intervene in this problem and the exact computation of the Delaunay graph and the Voronoi diagram of spheres. To the best of our knowledge, there does not exist a comprehensive treatment of the exact computation with geometrical invariants of the Delaunay graph and the Voronoi diagram of spheres. Starting from the system of equations defining the zero-dimensional algebraic set of the problem, we are applying Wu＇s algorithm to transform the initial system into an equivalent Wu characteristic （triangular） set. In the corresponding system of algebraic equations, in each polynomial （except the first one）, the variable with higher order from the preceding polynomial has been eliminated （by pseudo-remainder computations） and the last polynomial we obtain is a polynomial of a single variable. By regrouping all the formal coefficients for each monomial in each polynomial, we get polynomials that are invariants for the given problem. We rewrite the original system by replacing the invariant polynomials by new formal coefficients. We repeat the process until all the algebraic relationships （syzygies） between the invariants have been found by applying Wu＇s algorithm on the invariants. Finally, we present an incremental algorithm for the construction of Voronoi diagrams and Delaunay graphs of spheres in 3D and its application to Geodesy.

关键词： Voronoi diagram of spheres Delaunay graph of spheres Wu's method invariant characteristic set

Effect of age and different doses of dietary vitamin E on breast meat qualitative characteristics of finishing broilers

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Animal Nutrition 2021年第1期7卷 163-167页

作者： Vivian Vieira Francielle O.Marx Lucas S.Bassi Marley c.santos Alexandre Oba Simone Gisele de Oliveira Alex Maiorka Federal University of Paraná Curitiba80035-050Brazil State University of Londrina Londrina86055-900Brazil

The supplementation of vitamin E on broiler chicken diets is essential to the prevention of lipid oxidation reactions in the meat and improvement of meat *** objective of this study was to assess the effect of different doses of dietary vitamin E on breast meat quality of broiler chickens in the finishing *** doses of vitamin E were used(30,90,150,210,and 270 mg/kg feed)in broilers'diets from 42 to 54 d of age.A completely randomized design was conducted,followed by a split-plot,where the vitamin E dose was considered as the whole plot,and broilers'age at slaughter was the *** meat quality was assessed at 4 different ages(45,48,51,and 54 d old),using 50 birds per age,totaling 200 *** quality characteristics evaluated were:pH at 24 h post mortem,color(brightness,redness,and yellowness),water holding capacity,cooking loss,shear force,and lipid *** was no interaction between age and dose of vitamin E for meat quality characteristics(P>0.05).The age at slaughter had a quadratic effect(Pce value was higher in breast meat of birds slaughtered at later ages(Pct was *** increased linearly(Pcooking loss,and lipid *** this study,increasing vitamin E doses in the finishing period increased the brightness of broiler breast meat,whereas slaughtering at later ages resulted in greater meat pH and shear force value.

关键词： Alpha-tocopherol Broiler chicken Meat quality Oxidation Vitamin

Growth mechanism of octahedron-like BaMoO_4 microcrystals processed in microwave-hydrothermal:Experimental observations and computational modeling

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Particuology 2009年第5期7卷 353-362页

作者： Laécio santos cavalcante Júlio césar Sczancoski Rircado Luis Tranquilin José Arana Varela Elson Longo marcelo Ornaghi Orlandi Departamento de Química UFSCarP.O. Box 67613565-905So CarlosSPBrazil Instituto de Química-UNESP P.O. Box 35514801-907AraraquaraSPBrazil

Octahedron-like BaMoO4 microcrystals were synthesized by the co-precipitation method at room temperature and processed in microwave-hydrothermal at 413 K for different times （from 30 min to 5 h）. These microcrystals were analyzed by X-ray diffraction （XRD）, field-emission gun scanning electron microscopy （FEG-SEM） and transmission electron microscopy （TEM）. XRD patterns showed that this material presents a tetragonal structure without the presence of deleterious phases. FEG-SEM and TEM micrographs revealed that the BaMoO4 microcrystals present an octahedron-like morphology with agglomerate nature and polydisperse particle size distribution. These micrographs also indicated that the microcrystals grow along the [0 01 ] direction. The observed crystallographic planes in these structures were modeled computationally and a crystal growth model was proposed in order to explain the morphological changes as a function of processing time.

关键词： BaMoO4 Growth process Microwave-hydrotherma Supersaturated solution

MGMT and MLH1 methylation in Helicobacter pylori-infected children and adults

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World Journal of Gastroenterology 2013年第20期19卷 3043-3051页

作者： Marisa c Alvarez Juliana c.santos Nathália Maniezzo marcelo S Ladeira Artur Lc da Silva Isabel cA Scaletsky José Pedrazzoli Jr marcelo L Ribeiro Unidade Integrada de Farmacologia e Gastroenterologia Universidade So FranciscoBragan a Paulista 12916-900SPBrazil Programa de Pós Gradua o em Genética e Biologia Molecular State University of CampinasCampinas 13083-970SPBrazil Departamento de clínica Médica UNESPBotucatu 18618-970SPBrazil Departamento de Genética Universidade Federal do ParáBelém 68400-000PABrazil Departamento de Microbiologia Imunologia e ParasitologiaUniversidade Federal de So PauloSo Paulo 04021-001SPBrazil

AIM:To evaluate the association between Helicobacter pylori(***) infection and MLH1 and MGMT methylation and its relationship with microsatellite instability(MSI).METHODS:The methylation status of the MLH1 and MGMT promoter region was analysed by methylation specific methylation-polymerase chain reaction(MSPPcR) in gastric biopsy samples from uninfected or ***-infected children(n = 50),from adults with chronic gastritis(n = 97) and from adults with gastric cancer(n = 92).MLH1 and MGMT mRNA expression were measured by real-time PcR and normalised to a constitutive gene(β actin).MSI analysis was performed by screening MSI markers at 4 loci(Bat-25,Bat-26,D17S250 and D2S123) with PcR;PcR products were analysed by single strand conformation polymorphism followed by silver *** analyses were performed with either the χ 2 test with Yates continuity correction or Fisher's exact test,and statistical significance for expression analysis was assessed using an unpaired Student's ***:Methylation was not detected in the promoter regions of MLH1 and MGMT in gastric biopsy samples from children,regardless of *** infection *** MGMT promoter was methylated in 51% of chronic gastritis adult patients and was associated with *** infection(P c cancer patients,and the difference in the percentage of methylated samples between these patients and those from ***-infected chronic gastritis patients was statistically significant(P cies among ***-infected and non-infected chronic gastritis adult patients were 13% and 7%,*** observed methylation of the MLH1 promoter(39%) and increased MSI levels(68%) in samples from gastric cancer patients in comparison to samples from ***-infected adult chronic gastritis patients(P ctively).The frequency of promoter methylation for both genes was higher in gastric cancer sam

关键词： Helicobacter pylori Microsatellite instability Promoter methylation MLH1 MGMT Gastric cancer

Optimizing the use of open chambers to measure ammonia volatilization in field plots amended with urea

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Pedosphere 2021年第2期31卷 243-254页

作者： Márcio R.MARTINS Leonardo F.SARKIS Selenobaldo A.c.SANT’ANNA camila A.santos Karla E.ARAUJO Ricardo c.santos Ednaldo S.ARAÚJO Bruno J.R.ALVES claudia P.JANTALIA Robert M.BODDEY Mohammad ZAMAN Segundo URQUIAGA Embrapa Agrobiology Rod.BR 465km 7Seropédica RJ CEP 23891-000(Brazil) Federal Rural University of Rio de Janeiro(UFRRJ) Rod.BR 465km 7Seropédica RJ CEP 23891-000(Brazil) Agroscope Research Division Agroecology and EnvironmentClimate and Agriculture GroupReckenholzstrasse 191Zurich 8046(Switzerland) Soil and Water Management&crop Nutrition Joint FAO/IAEA Division of Nuclear Techniques in Food&AgricultureP.O.Box 100Vienna A-1400(Austria)

Measuring ammonia(NH_(3))volatilization from urea-fertilized soils is crucial for evaluation of practices that reduce gaseous nitrogen(N)losses in *** small area of chambers used for NH_(3)volatilization measurements compared with the size of field plots may cause significant errors if inadequate sampling strategies are *** aims were:i)to investigate the effect of using multiple open chambers on the variability in the measurement of NH_(3)volatilization in urea-amended field plots and ii)to define the critical period of NH_(3)-N losses during which the concentration of sampling effort is capable of reducing *** use of only one chamber covering 0.015%of the plot(51.84 m^(2))generates a value of NH_(3)-N loss within an expected margin of error of 30%around the true *** reduce the error margin by half(15%),3–7 chambers were required with a mean of 5 chambers per *** the sampling efforts in the first two weeks after urea application,which is usually the most critical period of N losses and associated errors,represents an efficient strategy to lessen uncertainty in the measurements of NH_(3)*** strategy enhances the power of detection of NH_(3)-N loss abatement in field experiments using chambers.

关键词： chamber method experimental error gas emission low-cost chamber nitrogen cycling nitrogen loss soil variability

Thermal Behavior of Sr（ll） and Ba（ll）-Diclofenac complexes in Solid State： Study of the Dehydration and Thermal Decomposition

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chinese Journal of chemistry 2011年第11期29卷 2271-2277页

作者： Kobelnik, marcelo cassimiro, Douglas Lopes santos, Diogenesdos Dos Ribeiro, clovis Augusto crespi, Marisa Spirandelic centro Universitdrio do Norte Paulista-UNORP Rua Ipiranga 3460 Sao Jose do Rio Preto SP Brazil Instituto de Quimica Sao Paulo State University C.P. 355 14800-900 Araraquara SP Brazil

Solid state compounds of general formula Sr（Diclof）2 ·5.7H2O and Ba（Diclof）2·4.8H2O were obtained. Thermo- gravimetry （TG）, differential scanning calorimetry （DSc）, X-ray diffraction powder patterns and microscopy analysis were used to characterize these compounds. Details concerning the dehydration and thermal decomposition as well as data of kinetic parameters have been described here. The kinetic behaviors of these stages were evaluated from several heating rates with samples masses of 2 and 5 mg in open crucibles under a nitrogen atmosphere. The results of the present study improve the knowledge on these compounds including their dehydration and thermal stability. The obtained data depend on the mass of the sample which results in two kinetic behavior patterns.

关键词： diclofenac divalent metal ions thermal behavior kinetic parameters

capacitorless Solid-state Power Filter for Single-phase Dc-Ac converters

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cES Transactions on Electrical Machines and Systems 2024年第3期8卷 367-377页

作者： Haitham Kanakri Euzeli c.Dos santos Purdue University Electrical and Computer Engineering DepartmentIndianapolisIN46202 USA

converters rely on passive filtering as a crucial element due to the high-frequency operational characteristics of power *** filtering methods involve a dual inductor-capacitor(Lc)cell or an inductor-capacitor-inductor(LcL)***,capacitors are susceptible to wear-out mechanisms and failure ***,the necessity for monitoring and regular replacement adds to an elevated cost of ownership for such *** utilization of an active output power filter can be used to diminish the dimensions of the Lc filter and the electrolytic dc-link capacitor,even though the inclusion of capacitors remains an indispensable part of the *** paper introduces capacitorless solid-state power filter(SSPF)for single-phase dc-ac *** proposed configuration is capable of generating a sinusoidal ac voltage without relying on *** proposed filter,composed of a planar transformer and an H-bridge converter operating at high frequency,injects voltage harmonics to attain a sinusoidal output *** design parameters of the planar transformer are incorporated,and the impact of magnetizing and leakage inductances on the operation of the SSPF is *** analysis,supported by simulation and experimental results,are provided for a design example for a single-phase *** total harmonic distortion observed in the output voltage is well below the IEEE 519 *** system operation is experimentally tested under both steady-state and dynamic conditions.A comparison with existing technology is presented,demonstrating that the proposed topology reduces the passive components used for filtering.

关键词： Solid-state power filter(SSPF) capacitorless topology Active output power filter(AOF) Planar transformer Electrolytic capacitor Lifetime Wear-out mechanisms

comment on “constraining the smoothness parameter and dark energy using observational H(z) data”

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Research in Astronomy and Astrophysics 2011年第6期11卷 637-640页

作者： V.c.Busti R.c.santos Instituto de Astronomia Geofísica e Ciências AtmosféricasUniversidade de So PauloSo Paulo05508-090 SPBrazil Departamento de ciê ncias Exatas e da Terra Universidade Federal de So Paulo(UNIFESP)Diadema09972-270 SPBrazil

We discuss a recent analysis by Yu et al.[RAA 11,125（2011）] about constraints on the smoothness parameter α and dark energy models using observational H（z） *** is argued here that their procedure is conceptually inconsistent with the basic assumptions underlying the adopted Dyer-Roeder *** order to properly quantify the influence of the H（z） data on the smoothness parameter α,a χ2-test involving a sample of type Ia supernovae and H（z） data in the context of a flat ΛcDM model is *** result is confronted with an earlier approach discussed by santos et al.（2008） without H（z） *** the（Ωm,α） plane,it is found that such parameters are now restricted to be in the intervals 0.66 ≤ α ≤ 1.0 and 0.27 ≤ Ωm ≤ 0.37 within the 95.4 confidence level（2σ）,and,therefore,are fully compatible with the homogeneous *** basic conclusion is that a joint analysis involving H（z） data can indirectly improve our knowledge about the influence of the ***,this happens only because the H（z） data provide tighter constraints on the matter density parameter Ωm.

关键词： cosmology — dark energy — cosmological parameters