1,691 research outputs found
Oral health-related quality of life following dental treatment under general anaesthesia for early childhood caries - a UK-based study.
Objective
To assess parental reports of changes in oral health-related quality of life (OHRQoL) of young children in the UK with early childhood caries (ECC) following dental treatment under general anaesthesia (DGA). To compare the impact of oral rehabilitation (OR) and extraction-only (Exo) treatment approaches on this.
Methods
Data were collected using the proxy reported components of the Child Oral Health-Related Quality of Life (COHRQoL®) questionnaire: the Parent-Caregivers Perceptions questionnaire (P-CPQ) and Family Impact Scale (FIS), from a convenience sample of parents of children receiving DGA at a UK Paediatric Dental Department. Mean scores and prevalence impacts were compared pre- and postoperatively with mean change score and effect sizes calculations.
Results
Seventy-eight parents were recruited (51 children undergoing OR, 27 Exo) with 6 lost to follow-up (92.3%). Following treatment, changes in mean P-CPQ and FIS scores were statistically significant (P < 0.0001) with medium to large effect sizes (0.45–1.39). The differences in change scores between the two treatment approaches were not statistically different.
Conclusion
DGA for young children with early childhood caries resulted in substantial improvements in parent's ratings of their child's OHRQoL and of the impact on their families. Larger cohort studies are needed to validate these preliminary findings
Brachiaria As A Cover Crop To Improve Phosphorus Use Efficiency In A No-till Oxisol
Oxidic soils are phosphorus drains in soil; hence, P availability is a limiting factor in tropical, weathered Oxidic soils. It has been shown that some brachiarias grown as cover crops may increase soil available P to subsequent crops. The objective of this study was to evaluate soil P cycling and availability, as well as the response of soybean to soluble and natural reactive phosphates as affected by ruzi grass (Urochloa ruziziensis, R. Germ. and C.M. Evrard, Crin) grown as a cover crop in a no-till system. Experimental treatments consisted of the presence or absence of ruzi grass in combination with a control (0.0 P) and soluble and reactive rock phosphate broadcast on the soil surface in the winter (80 kg ha-1 P2O2), plus three rates of P applied to soybean furrows (0, 30, and 60 kg ha-1 of P2O5) at planting, in the form of triple superphosphate. Soybean was cropped in two seasons: 2010/2011 and 2011/2012. Soil samples were taken before soybean planting (after desiccation of Brachiaria) at 0.00-0.05 and 0.05-0.10 m for soil available P. Total weight of dry matter and P accumulated in ruzi grass were determined, as well as soybean yields, P in soybean grains, and P use efficiency (PUE). The use of natural phosphate increased soil P availability. The highest yields were obtained with higher application rates of triple superphosphate in the planting furrow combined with broadcast rock phosphate. Broadcast application of Arad reactive phosphate increases and maintains soil available P, and this practice, associated with ruzi grass grown as a cover crop and the use of triple superphosphate applied to soybean furrows, results in higher use of P by soybeans. © 2016, Revista Brasileira de Ciencia do Solo. All rights reserved.4
Medida de umidade do solo com sonda de nêutrons nas proximidades da superfície
The problem of neutron probe soil water content measurements close to soil surface is analysed from the spatial variability and also from the slow neutron "loss" to the atmosphere points of view. Results obtained on a dark red latosol of the county of Piracicaba,SP, indicate the possibility of precisely measuring the neutron "sphere of influence" when different media are used on soil surface.O problema da medida da umidade nas proximidades da superfície do solo é abordado do ponto de vista de sua variabitidade espacial e da "perda" de nêutrons lentos para a atmosfera. Dados, obtidos em terra roxa estruturada do município de Piracicaba,SP, mostram a possibilidade de se avaliar, com precisão, a "esfera de influência" da medida, quando se utilizam meios diferentes na superfície do solo
In Vitro Activity Of Artemisia Annua L (asteraceae) Extracts Against Rhipicephalus (boophilus) Microplus [atividade In Vitro De Extratos De Artemisia Annua L (asteraceae) Sobre Rhipicephalus (boophilus) Microplus]
The activity of plant extracts on parasites may indicate groups of substances that are potentially useful for controlling Rhipicephalus (Boophilus) microplus. The aim of the present study was to investigate the in vitro action of Artemisia annua extracts on this tick. The concentrations of the sesquiterpene lactones artemisinin and deoxyartemisinin present in plant extracts were quantified via high-performance liquid chromatography. Four extracts produced from the concentrated crude extract (CCE) were evaluated on larvae using the impregnated paper method, with readings after 24 hours of incubation. The engorged females were immersed in the CCE and in its four derived extracts for five minutes, with incubation for subsequent analysis of biological parameters. The extracts were not effective on the larvae at the concentrations tested (3.1 to 50 mg.mL-1). The CCE showed greater efficacy on engorged females (EC50 of 130.6 mg.mL-1 and EC90 of 302.9 mg.mL-1) than did the derived extracts. These results tend to confirm that the action of artemisinin on engorged females of R. (B.) microplus is conditional to their blood intake. In this case, in vitro methods would be inadequate for effective evaluation of the action of A. annua on R. (B.) microplus.2013135Amaral, N.K., Guidelines for the evaluation of ixodicides against the cattle tick Boophilus microplus (Canestrini, 1887) (Acari: Ixodidae) (1993) Revista Brasileira De Parasitologia Veterinária, 2 (2), pp. 144-151(2009) Anuário Da Pecuária Brasileira, p. 360. , ANUALPEC, Sao Paulo: Angra FNP PesquisasBorges, L.M.F., Acao do extrato hexanico de frutos maduros de Melia azedarach (Meliaceae) sobre Boophilus microplus (Acari: Ixodidae) em bezerros infestados artificialmente (2005) Revista De Patologia Tropical, 34 (1), pp. 53-59Cala, A.C., (2010) Avaliação Da Atividade De Artemisia Annua L., Melia Azedarach L. E Trichilia Claussenii C. Sobre Nematódeos Gastrintestinais De Ovinos, p. 64. , Dissertacao (Mestrado)- Universidade Estadual Paulista, Faculdade de Ciencias Agrarias e Veterinarias, JaboticabalCeleghini, R.M.S., Desenvolvimento e validacao de metodologia analitica por CLAE-IR para determinacao de artemisinina em Artemisia annua L (2009) Química Nova, 32 (4), pp. 875-878Chagas, A.C.S., Efeito acaricida de oleos essenciais e concentrados emulsionaveis de Eucalyptus em Boophilus microplus (2002) Brazilian Journal of Veterinary Research and Animal Science, 39 (5), pp. 247-253Chagas, A.C.S., Sensibilidade do carrapato Boophilus microplus a solventes (2003) Ciência Rural, 33 (1), pp. 109-114Creek, D.J., Kinetics of ironmediated artemisinin degradation:Effect of solvent composition and iron salt (2005) Journal of Pharmaceutical Sciences, 94 (8), pp. 1820-1829Drummond, R.O., Boophilus annulatus and B. Microplus: Laboratory tests of insecticides (1973) Journal of Economic Entomology, 66 (1), pp. 130-133Ekanem, A.P., Brisibe, E.A., Effects of ethanol extract of Artemisia annua L. Against monogenean parasites of Heterobranchus longifilis (2010) Parasitology Research, 106 (5), pp. 1135-1139Fernandes, F.F., Freitas, E.P.S., Acaricidal activity of an oleoresinous extract from Copaifera reticulata (Leguminosae: Caesalpinioideae against larvae of the southern cattle tick, Riphicephalus (Boophilus) microplus (Acari:Ixodidae) (2007) Veterinary Parasitology, 147 (1-2), pp. 150-154Ferreira, J.F.S., Agrotechnological aspects of the anti-malarial plant Artemisia annua and its potential use in animal health in Appalachia (2006) International Symposium on Perfume, Aromatic and Medicinal Plants, (2-4), pp. 797-804. , Revue de Regions Arides - Numero special - Actes du seminaire international les Plants a Parfum, Aromatiques et Medicinales (English version: International Center for Agricultural Research in Dry AreasFerreira, J.F.S., Nutrient Deficiency in the Production of Artemisinin, Dihydroartemisinic Acid, and Artemisinic Acid in Artemisia annua L (2007) Journal of Agricultural and Food Chemistry, 55 (5), pp. 1686-1694Ferreira, J.F.S., Gonzalez, J.M., Chemical and biological stability of artemisinin in bovine rumen fluid and its kinetics in goats (Capra hircus) (2008) Revista Brasileira De Parasitologia Veterinária, 17 (SUPPL. 1), pp. 103-109Furlong, J., O carrapato dos bovinos e a resistencia: Temos o que comemorar? (2007) A Hora Veterinária, 159, pp. 26-32Grisi, L., Impacto economico das principais ectoparasitoses em bovinos no Brasil (2002) A Hora Veterinária, 21 (125), pp. 8-10Heimerdinger, A., Extrato alcoolico de Capim-cidreira (Cymbopogon citratus) no controle do Boophilus microplus em bovinos (2006) Revista Brasileira De Parasitologia Veterinária, 15 (1), pp. 37-39Idris, U.A., Adam, S.E., Tartour, G., The anthelmintic efficacy of Artemisia herba-alba against Haemonchus contortus infection in goats (1982) Animal Health Quarterly, 22 (3), pp. 138-143Iqbal, Z., Anthelmintic activity of Artemisia brevifolia in sheep (2004) Journal of Ethnopharmacology, 93 (2), pp. 265-268Keiser, J., Artesunate and artemether are effective fasciolicides in the rat model and in vitro (2006) Journal of Antimicrobial Chemotherapy, 57 (6), pp. 1139-1145Keiser, J., Efficacy and safety of artemether against a natural Fasciola hepatica infection in sheep (2008) Parasitology Research, 103 (3), pp. 517-522Keiser, J., Utzinger, J., Food-borne trematodiasis: Current chemotherapy and advances with artemisinins and synthetic trioxolanes (2007) Trends In Parasitology, 23 (11), pp. 555-562Klayman, D.L., Qinghaosu (Artemisinin): Na antimalarial drug from China (1985) Science, 228 (4703), pp. 1049-1055La-Scalea, M.A., Silva, H.S.R.C., Ferreira, E., Reducao voltametrica de artemisinina e sua interacao com grupo heme (hemina) (2007) Brazilian Journal of Pharmaceutical Sciences, 43 (3), pp. 371-383Martins, R.M., Estudio in vitro de la accion acaricida del aceite esencial de la graminea Citronela de Java (Cymbopogon winterianus Jowitt) en la garrapata Boophilus microplus (2006) Revista Brasileira De Plantas Medicinais De Botucatu, 8 (2), pp. 71-78Meshnick, S.R., Second-generation antimamalarial endoperoxides (1996) Parasitology Today, 12 (2), pp. 79-82Ribeiro, V.L.S., Acaricidal properties of extracts from the aerial parts of Hypericum polyanthemum on the cattle tick Boophilus microplus (2007) Veterinary Parasitology, 147 (1-2), pp. 199-203Rodrigues, R.A.F., Otimizacao do processo de extracao e isolamento do antimalarico artemisinina a partir de Artemisia annua L (2006) Química Nova, 29 (2), pp. 368-372Silva, H.S.R.C., (2006) Antimaláricos Potenciais: Pró-fármacos Poliméricos E Formas De Liberação Controlada De Artemisinina, p. 209. , Tese (Doutorado)-Universidade de Sao Paulo, Sao PauloSimoes, C.M., (2004) Farmacognosia: Da Planta Ao Medicamento, p. 1102. , 5. ed. Porto Alegre: Editora da UFRGSFlorianopolis: Editora da UFSCTaranto, A.G., Estudo sobre o mecanismo de acao da artemisinina e dos endoperoxidos, a mais nova classe de agents antimalaricos (2006) Sitientibus, 34, pp. 47-58Tariq, K.A., Anthelmintic activity of extracts of Artemisia absinthium against ovine nematodes (2009) Veterinary Parasitology, 160 (1-2), pp. 83-8
Mixedness and entanglement for two-mode Gaussian states
We analytically exploit the two-mode Gaussian states nonunitary dynamics. We
show that in the zero temperature limit, entanglement sudden death (ESD) will
always occur for symmetric states (where initial single mode compression is
) provided the two mode squeezing satisfies We also give the analytical expressions for the time of ESD.
Finally, we show the relation between the single modes initial impurities and
the initial entanglement, where we exhibit that the later is suppressed by the
former.Comment: Accepted for publication in Optics Communication
Optical And Esr Study Of Er3+ In Linbo3
We report laser-excited optical transitions between the 4S3/2 and 4I15/2 multiplets of Er3+ as an impurity in the LiNbO3 host, together with the optical-absorption spectra at liquid-helium and liquid-nitrogen temperatures. The optical data allow us to determine the crystal-field splittings of those levels and the spin-Hamiltonian parameters for the 4I15/2 lower multiplet. The observed electron-spin resonance and the angular variation of this spectrum agree with the parameters obtained by optical techniques. Both techniques show that only one of the three possible trigonal sites in LiNbO3 is occupied by Er3+ within the experimental sensitivity, in agreement with recent x-ray standing-wave measurements. © 1995 The American Physical Society.5153206320
Detection Of An Untyped Strain Of Bovine Respiratory Syncytial Virus In A Dairy Herd
Bovine respiratory syncytial virus (BRSV) causes important lower respiratory tract illness in calves. According to F and G proteins genetic sequences, three BRSV subgroups have been reported and characterized in several countries, showing differences in its distribution. In Brazil, the virus is widely disseminated throughout the herds and the few characterized isolates revealed the solely occurrence of the subgroup B. This study describes the detection and characterization of an untyped BRSV strain from a twenty-days-old calf from a herd without clinical respiratory disease. Nasal swabs were analyzed by RT-nested PCR for the F and G proteins genes. One sample has amplified the F protein gene. Sequencing and subsequent phylogenetic reconstruction were accomplished, revealing that the strain could not be grouped with any other BRSV subgroups reported. This result may suggest that the BRSV is in constantly evolution, even in Brazil, where the vaccination is not a common practice. More detailed studies about BRSV characterization are necessary to know the virus subgroups distribution among the Brazilian herds to recommend appropriated immunoprophylaxis.35525392550Affonso, I.B., Gatti, S.P., Alexandrino, B., Oliveira, M.C., Medeiros, A.S.R., Buzinaro, M.G., Samara, S.I., Detection of antibodies against bovine respiratory syncytial virus (BRSV) in dairy cattle with different prevalences of bovine herpesvirus type 1 (BHV-1) in São Paulo State, Brazil (2011) Semina: Ciências Agrárias, 32 (1), pp. 295-300. , LondrinaAlmeida, R.S., Domingues, H.G., Spilki, F.R., Larsen, L.E., Hagglund, S., Belák, S., Arns, C.W., Circulation of bovine respiratory syncytial virus in Brazil (2006) Veterinary Record, 158 (18), pp. 632-634. , LondonAlmeida, R.S., Spilki, F.R., Roehe, P.M., Arns, C.W., Detection of Brazilian bovine respiratory syncytial virus strain by a reverse transcriptase-nestedpolymerase chain reaction in experimentally infected calves (2005) Veterinary Microbiology, 105 (2), pp. 131-135. , AmsterdamArns, C.W., Campalans, J., Costa, S.C.B., Domingues, H.G., D'Arce, R.C.F., Almeida, R.S., Characterization of bovine respiratory syncytial virus isolated in Brazil (2003) Brazilian Journal of Medical and Biological Research, 36 (2), pp. 213-218. , Ribeirão PretoBaker, J.C., Frey, M., Bovine respiratory syncytial virus (1985) Veterinary Clinics of North America: Food Animal Practice, 1 (2), pp. 259-272. , PhiladelphiaBidokhti, M.R.M., Travén, M., Ohlson, A., Zarnegar, B., Baule, C., Belák, S., Alenius, S., Liu, L., Phylogenetic analysis of bovine respiratory syncytial viruses from recent outbreaks in feedlot and dairy cattle herds (2012) Archives of Virology, 157 (4), pp. 601-607. , New YorkBunt, A.A., Milne, R.G., Sayaya, T., Verbeek, M., Vetten, H.J., Walsh, J.A., Paramyxoviridae (2005) Virus Taxonomy, Eigth Report of the International Committee on Taxonomy of Viruses, pp. 655-671. , In: FAUQUET, C. M.MAYO, M. A.MANILOFF, J.DESSELBERGER, U.BALL, L. A. (Ed.). London: Elsevier: Academic PressCampalans, J., Arns, C.W., Serological evidence of bovine respiratory syncytial virus in Brazil (1997) Virus Reviews and Research, 2 (1-2), pp. 50-56. , Belo HorizonteDomingues, H.G., Spilki, F.R., Arns, C.W., Detecção molecular e análise filogenética de vírus respiratório sincicial bovino (BRSV) em swabs e tecido pulmonar de bovinos adultos (2011) Pesquisa Veterinária Brasileira, 31 (11), pp. 961-966. , Rio de JaneiroFurze, J.M., Roberts, S.R., Wertz, G.W., Taylor, G., Antigenically distinct G glycoproteins of BRSV strains share a high degree of genetic homogeneity (1997) Virology, 231 (1), pp. 48-58. , New YorkFurze, J., Wertz, G., Lerch, R., Taylor, G., Antigenic heterogeneity of the attachment protein of bovine respiratory syncytial virus (1994) Journal of General Virology, 75 (2), pp. 363-370. , LondonGonçalves, I.P.D., Simanke, A.T., Jost, H.C., Hötzel, I., Dal Soglio, A., Moojen, V., Detection of bovine respiratory syncytial virus in calves of Rio Grande do Sul, Brazil (1993) Ciência Rural, 23 (3), pp. 389-390. , Santa MariaHall, T.A., BioEdit: A user-friendly biological sequence alignment editor and analysis program for Windows 95/98/NT (1999) Nucleic Acids Symposium Series, 41, pp. 95-98. , OxfordLarsen, L.E., Bovine respiratory syncytial virus (BRSV): A review (2000) Acta Veterinaria Scandinavica, 41 (1), pp. 1-24. , CopenhagenLarsen, L.E., Tjornehoj, K., Viuff, B., Extensive sequence divergence among bovine respiratory syncytial viruses isolated during recurrent outbreaks in closed herds (2000) Journal of Clinical Microbiology, 38 (11), pp. 4222-4227. , WashingtonNettleton, P.F., Gilray, J.A., Caldow, G., Gidlow, J.R., Durkovic, B., Vilcek, S., Recent isolates of Bovine respiratory syncytial virus from Britain are more closely related to isolates from USA than to earlier British and current mainland European isolates (2003) Journal of Veterinary Medicine Series B-Infectious Diseases and Veterinary Public Health, 50 (4), pp. 196-199. , BerlinProzzi, D., Walravens, K., Langedijk, J.P., Daus, F., Kramps, J.A., Letesson, J.J., Antigenic and molecular analyses of the variability of bovine respiratory syncytial virus G glycoprotein (1997) Journal of General Virology, 78 (2), pp. 359-366. , LondonSchrijver, R.S., Daus, F., Kramps, J.A., Langedijk, J.P.M., Buijs, R., Middel, W.G.J., Taylor, G., Van Oirschot, J.T., Subgrouping of bovine respiratory syncytial virus strains detected in lung tissue (1996) Veterinary Microbiology, 53 (3-4), pp. 253-260. , AmsterdamSchrijver, R.S., Langedijk, J.P.M., Poel, V.D.M.W.H., Middel, W.G.J., Kramps, J.A., Van Oirschot, J.T., Antibody responses against the G and F proteins of bovine respiratory syncytial virus after experimental and natural infections (1996) Clinical and Diagnostic Laboratory Immunology, 3 (5), pp. 500-506. , WashingtonSchrijver, R.S., Langedijk, J.P.M., Middel, W.G.J., Kramps, J.A., Rijsewijk, F.A.M., Van Oirschot, J.T., A bovine respiratory syncytial virus strain with mutations in subgroup-specific antigenic domains of the G protein induces partial heterologous protection in cattle (1998) Veterinary Microbiology, 63 (2-4), pp. 159-175. , AmsterdamSpilki, F.R., Almeida, R.S., Domingues, H.G., D'Arce, R.C.F., Ferreira, H.L., Campalans, J., Costa, S.C.B., Arns, C.W., Phylogenetic relationships of Brazilian bovine respiratory syncyctial virus isolates and molecular homology modeling of attachment glycoprotein (2006) Virus Research, 116 (1-2), pp. 161-168. , AmsterdamSpilki, F.R., Arns, C.W., Vírus respiratório sincicial bovino (2008) Acta Scientiae Veterinariae, 36 (3), pp. 197-214. , Porto AlegreStine, L.C., Hoppe, D.K., Clayton, L.K., Sequence conservation in attachment glycoproteins and antigenic diversity among bovine respiratory syncytial virus isolates (1997) Veterinary Microbiology, 54 (3-4), pp. 201-221. , AmsterdamTamura, K., Dudley, J., Nei, M., Kumar, S., MEGA 4: Molecular evolutionary genetics analysis (MEGA) software version 4.0 (2007) Molecular Biology and Evolution, 24 (8), pp. 1596-1599. , ChicagoTaylor, G., Stott, E.J., Furze, J., Ford, J., Sopp, P., Protective epitopes on the fusion protein of respiratory syncytial virus recognized by murine and bovine monoclonal antibodies (1992) Journal of General Virology, 73 (9), pp. 2217-2223. , LondonTaylor, G., Thomas, L.H., Furze, J.M., Cook, R.S., Wyld, S.G., Lerch, R., Hardy, R., Wertz, G.W., Recombinant vaccinia viruses expressing the F, G or N, but not the M2, protein of bovine respiratory syncytial virus (BRSV) induce resistance to BRSV challenge in the calf and protect against the development of pneumonic lesions (1997) Journal of General Virology, 78 (12), pp. 3195-3206. , LondonThomas, L.H., Cook, R.S., Wyld, S.G., Furze, J.M., Taylor, G., Passive protection of gnotobiotic calves using monoclonal antibodies directed at different epitopes on the fusion protein of bovine respiratory syncytial virus (1998) Journal of Infectious Diseases, 177 (4), pp. 874-880. , ChicagoThompson, J.D., Higgins, D.G., Gibson, T.J., Clustal W: Improving the sensitivity of progressive multiple sequence alignment through sequence weighting, positions-specific gag penalties and weight matrix choice (1994) Nucleic Acids Research, 22 (22), pp. 4673-4680. , OxfordValarcher, J.F., Schelcher, F., Bourhy, H., Evolution of bovine respiratory syncytial virus (2000) Journal of Virology, 74 (22), pp. 10714-10728. , WashingtonValarcher, J.F., Taylor, G., Bovine respiratory syncytial virus infection (2007) Veterinary Research, 38 (2), pp. 153-180. , Les UlisPoel, V.D.W., Brand, A., Kramps, J.A., Van Oirschot, J.T., Respiratory syncytial virus infections in human beings and in cattle (1994) Journal of Infectious Diseases, 29 (2), pp. 215-228. , ChicagoVilcek, S., Elvander, M., Ballagi-Pordány, A., Belák, S., Development of nested PCR assays for detection of bovine respiratory syncytial virus in clinical samples (1994) Journal of Clinical Microbiology, 32 (9), pp. 2225-2231. , WashingtonWoelk, C.H., Holmes, E.C., Variable immune-driven natural selection in the attachment (G) glycoprotein of respiratory syncytial virus (RSV) (2001) Journal of Molecular Evolution, 52 (2), pp. 182-192. , ChicagoYaegashi, G., Seimiya, Y.M., Seki, Y., Tsunemitsu, H., Genetic and antigenic analyses of bovine respiratory syncytial virus detected in Japan (2005) Journal of Veterinary Medical Science, 67 (2), pp. 145-150. , Toky
Quantifying the decay of quantum properties in single-mode states
The dissipative dynamics of Gaussian squeezed states (GSS) and coherent
superposition states (CSS) are analytically obtained and compared. Time scales
for sustaining different quantum properties such as squeezing, negativity of
the Wigner function or photon number distribution are calculated. Some of these
characteristic times also depend on initial conditions. For example, in the
particular case of squeezing, we find that while the squeezing of CSS is only
visible for small enough values of the field intensity, in GSS it is
independent of this quantity, which may be experimentally advantageous. The
asymptotic dynamics however is quite similar as revealed by the time evolution
of the fidelity between states of the two classes.Comment: Accepted versio
Estabilidade De Agregados Em Latossolos Sob Plantas De Cobertura Em Rotação Com Soja E Milho
The objective was to evaluate the effect of different covers on the stability of soil aggregates in two areas of Oxisols, grown in rotation with crops of soybean and corn. The experiments were installed in Votuporanga, São Paulo, Brazil and Selvíria, Mato Grosso do Sul, Brazil in March 2008. The experimental design was a randomized block with four replicates and the following cover crops in different spending ha-1 seeds, were the treatments: Sorghum bicolor, 6, 7 and 8 kg ha-1; Pennisetum americanum, 10, 15 and 20 kg ha-1; S. sudanense, 12, 15 and 18 kg ha-1; hybrid of S. bicolor and S. sudanense, 8, 9 and 10 kg ha-1; Urochloa ruziziensis, 8, 12 and 16 kg ha-1; plus, control treatment with spontaneous vegetation. We evaluated the dry matter yield of different covers and were separate classes of soil aggregates and calculated the average diameter. It is noted that the cover crops had similar behavior on aggregates stability in the surface layer, and in the greater depth, the S. sudanense was more efficient in improving the class mean diameter between 2.0-1.0 mm, in Votuporanga, and the P. americanum was more efficient from 4.0 to 2.0 mm and 2.0-1.0 mm in Selvíria. Lower spending seeds was more promising on aggregate stability.11315616
Alterações Físicas Em Latossolos Cultivados Com Plantas De Cobertura Em Rotação Com Soja E Milho
This study was conducted to evaluate the effect of different covers, grown in rotation with soybean and corn on the physical attributes of two Oxisols. The experiments were installed in Votuporanga, SP, Brazil and Selvíria, MS, Brazil in March 2008, after conventional tillage. The experimental design was a randomized complete block with four replications, using the following cover crops at different amounts of seeds: Sorghum bicolor, Pennisetum americanum, S. sudanense, hybrid of S. bicolor with S. sudanense, Urochloa ruziziensis and a control with spontaneous vegetation. We evaluated the dry matter yield of different covers, and macroporosity, microporosity, total porosity and bulk density, in the layers of 0-0.05, 0.05-0.20 and 0.20-0.40 m. It concludes that, different covers plants and seed amounts used for grains, seeds and forage after two years did not cause effects on some soil physical properties of the two Oxisols.11314915
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