366 research outputs found
Assessing the diversity of sea beet (Beta vulgaris L. ssp. maritima) populations
Beta vulgaris L. subsp. maritima (L.) Arcang., sea beet, is a morphologically and
genetically variable species, belonging to beet primary gene
-pool. This crop wild relative
is a valuable genetic resource for resistance improvement in beets and could play an
important role in crop yield sustainability. Eleven Madeiran sea beet populations were
characterized using morphological descriptors and genetic markers. Our goal was to
evaluate these populations as a potential source of valuable genetic material.
Morphological characterization showed a high quantitative variation among populations.
Plant height and inflorescence height parameters had the highest influence in the
separation of populations. Molecular analysis was performed with polymorphic SSRs to
determine genetic variability between populations. Both PCA and PCoA revealed three
clusters that separated the populations according to morphological and genetic traits,
respectively. This study contributes to the knowledge of sea beet diversity in Madeira’s
archipelago and to the perception that the islands' specific environmental conditions
influence its genetic variability, making these populations a possible gene source for sugar
beet breeding programsinfo:eu-repo/semantics/publishedVersio
Use of the flooded forest by fish assemblages in lakes of the National Park of Anavilhanas (Amazonas, Brazil)
Hybrid electrical energy generation from hydropower, solar photovoltaic and hydrogen
The global concern to reduce greenhouse gas emissions and increase the use of renewable sources has led Brazil to stand out as a promising nation in this context, with a large portion of its energy capacity coming from renewable sources. However, renewable sources have the disadvantage of intermittency and seasonality, which has prompted the search for solutions to these challenges. This study assesses the feasibility of integrating hydro and solar power with a Hydrogen-based Electrical Energy Storage System (H2EESS) at the Serra da Mesa hydroelectric Brazilian power plant. Hydrogen would be produced through water electrolysis, taking advantage of the available excess renewable energy, and subsequently converted back into electricity through fuel cells. The integration of hydro and solar power with H2EESS resulted in an increase of 11.10 % in the energy produced compared to conventional hydroelectric generation, with 36.06 % of this increase coming from H2EESS. Additionally, there was a 9.71 % increase in the utilization of substation capacity. These results highlight the feasibility and benefits of integrating hydro and solar power with H2EESS. This approach allows for maximizing renewable energy generation, reducing greenhouse gas emissions, and better utilizing available resources without the need for significant infrastructure investments
Screening for Drought Tolerance in Thirty Three Taro Cultivars
Taro [Colocasia esculenta (L.) Schott] is a root crop which is an important staple food in many regions of the world, producing 10.5 million tonnes on 1.4 million hectares a year. The crop is cultivated in wet (rain fed) or irrigated conditions, requiring on average 2,500 mm water per year, and in many countries it is cultivated in flooded plots. It is estimated that taro production could decrease by 40% as a result of the increase in drought and other severe events. In this work, thirty three accessions, including local cultivars, selected and hybrid lines were submitted to long duration drought stress and screened for tolerance. Twelve physiological, morphological and agronomic traits were measured at harvest, and subject to multivariate analysis. Stress indices, Water Use Efficiency and Factorial Analysis were useful for discriminating accessions regarding drought tolerance and yield stability, and drought tolerant and susceptible cultivars were identified. Our results confirm that different taro cultivars have different drought avoidance and tolerance strategies to cope with water scarcity. Better yield performers minimised biomass and canopy loss, while tolerance was observed in cultivars that presented low potential yield, but efficiently transferred resources to enhance corm formation. Among the 33 accessions, two local cultivars showed high yield stability and could be considered as suitable parents for breeding programs, while two others are well adapted to drought, but with overall low yield potential
Influence Of Surface Treatments On Enamel Susceptibility To Staining By Cigarette Smoke
Objectives: The purpose of this study was to evaluate the influence of remineralizing agents, including artificial saliva, neutral fluoride, and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), on the susceptibility of bleached enamel to staining by cigarette smoke. Study design: Fifty bovine enamel blocks were randomly divided into five groups (n = 10): G1- bleaching; G2- bleaching and immersion in artificial saliva; G3- bleaching and application of CPP-ACP; G4- bleaching and application of neutral fluoride; and G5- untreated (Control). Teeth were bleached with 35% hydrogen peroxide and treated with the appropriate remineralizing agent. After treatment, all groups were exposed to cigarette smoke. Enamel color measurements were performed at three different times: before treatment (T1), after treatment (bleaching and remineralizing agent) (T2), and after staining (T3), by using the CIE Lab method with a spectrophotometer. The data coordinate L* was evaluated by analysis of repeated-measures PROC MIXED and Tukey-Kramer's test, and the E values were submitted to one-way ANOVA and Tukey's test (a = 0.05). Results: The G1 group did not show any statistically significant difference for L* values between times T1 and T2. The G4 and G5 groups showed lower L* values at T3 compared to T2. No significant differences between the groups were observed for E (after treatment and staining). However, G4 showed a clinically apparent color change. Conclusions: Treatment of bleached enamel with neutral fluoride can contribute to the increased staining of enamel due to cigarette smoke. © Medicina Oral S. L. C.I.F. B 96689336 - eISSN: 1989-5488.54163168Lewinstein, I., Hirschfeld, Z., Stabholz, A., Rotstein, I., Effect of hydrogen peroxide and sodium perborate on the microhardness of human enamel and dentin (1994) J Endod., 20, pp. 61-3McEvoy, S.A., Chemical agents for removing intrinsic stains from vital teeth (1989) I. Technique development. Quintessence Int., 20, pp. 323-8Joiner, A., The bleaching of teeth: a review of the literature (2006) J Dent., 34, pp. 412-9Sulieman, M., An overview of bleaching techniques: I (2004) History, chemistry, safety and legal aspects. Dent Update., 31, pp. 608-10. , 612-4, 616McGuckin, R.S., Babin, J.F., Meyer, B.J., Alterations in human enamel surface morphology following vital bleaching (1992) J Prosthet Dent., 68, pp. 754-60Pinto, C.F., Oliveira, R.D., Cavalli, V., Giannini, M., Peroxide bleaching agent effects on enamel surface microhardness, roughness and morphology (2004) Braz Oral Res., 18, pp. 306-11Berger, S.B., Coelho, A.S., Oliveira, V.A., Cavalli, V., Giannini, M., Enamel susceptibility to red wine staining after 35% hydrogen peroxide bleaching (2008) J Appl Oral Sci., 16, pp. 201-4Setien, V., Roshan, S., Cala, C., Ramirez, R., Pigmentation susceptibility of teeth after bleaching with 2 systems: an in vitro study (2009) Quintessence Int., 40, pp. 47-52Ernst, C.P., Marroquín, B.B., Willershausen-Zönnchen, B., Effects of hydrogen peroxide-containing bleaching agents on the morphology of human enamel (1996) Quintessence Int., 27, pp. 53-6Josey, A.L., Meyers, I.A., Romaniuk, K., Symons, A.L., The effect of a vital bleaching technique on enamel surface morphology and the bonding of composite resin to enamel (1996) J Oral Rehabil., 23, pp. 244-50Attin, T., Kielbassa, A.M., Schwanenberg, M., Hellwig, E., Effect of fluoride treatment on remineralization of bleached enamel (1997) J Oral Rehabil., 24, pp. 282-6Serra, M.C., Cury, J.A., The in vitro effect of glass-ionomer cement restoration on enamel subjected to a demineralization and remineralization model (1992) Quintessence Int., 23, pp. 143-7ten Cate, J.M., Review on fluoride, with special emphasis on calcium fluoride mechanisms in caries prevention (1997) Eur J Oral Sci., 105, pp. 461-5Reynolds, E.C., Cai, F., Cochrane, N.J., Shen, P., Walker, G.D., Morgan, M.V., Fluoride and casein phosphopeptide-amorphous calcium phosphate (2008) J Dent Res., 87, pp. 344-8Cochrane, N.J., Cai, F., Huq, N.L., Burrow, M.F., Reynolds, E.C., New approaches to enhanced remineralization of tooth enamel (2010) J Dent Res., 89, pp. 1187-97Ferreira Sda, S., Araújo, J.L., Morhy, O.N., Tapety, C.M., Youssef, M.N., Sobral, M.A., The effect of fluoride therapies on the morphology of bleached human dental enamel (2011) Microsc Res Tech., 74, pp. 512-6Hamba, H., Nikaido, T., Inoue, G., Sadr, A., Tagami, J., Effects of CPPACP with sodium fluoride on inhibition of bovine enamel demineralization: a quantitative assessment using micro-computed tomography (2011) J Dent., 39, pp. 405-13Weir, A., Westerhoff, P., Fabricius, L., Hristovski, K., von Goetz, N., Titanium dioxide nanoparticles in food and personal care products (2012) Environ Sci Technol., 46, pp. 2242-50Cunha, A.G., De Vasconcelos, A.A., Borges, B.C., Vitoriano Jde, O., Alves-Junior, C., Machado, C.T., Efficacy of in-office bleaching techniques combined with the application of a casein phosphopeptideamorphous calcium phosphate paste at different moments and its influence on enamel surface properties (2012) Microsc Res Tech., 75, pp. 1019- 25Cavalli, V., Rodrigues, L.K., Paes-Leme, A.F., Brancalion, M.L., Arruda, M.A., Berger, S.B., Effects of bleaching agents containing fluoride and calcium on human enamel (2010) Quintessence Int., 41, pp. e157-65Liporoni, P.C., Souto, C.M., Pazinatto, R.B., Cesar, I.C., de Rego, M.A., Mathias, P., Enamel susceptibility to coffee and red wine staining at different intervals elapsed from bleaching: a photoreflectance spectrophotometry analysis (2010) Photomed Laser Surg., 28, pp. S105-9Rotstein, I., Dankner, E., Goldman, A., Heling, I., Stabholz, A., Zalkind, M., Histochemical analysis of dental hard tissues following bleaching (1996) J Endod., 22, pp. 23-5Cakir, F.Y., Korkmaz, Y., Firat, E., Oztas, S.S., Gurgan, S., Chemical analysis of enamel and dentin following the application of three different at-home bleaching systems (2011) Oper Dent., 36, pp. 529-36Kwon, Y.H., Huo, M.S., Kim, K.H., Kim, S.K., Kim, Y.J., Effects of hydrogen peroxide on the light reflectance and morphology of bovine enamel (2002) J Oral Rehabil., 29, pp. 473-7Gomes, M.N., Francci, C., Medeiros, I.S., De Godoy Froes Salgado, N.R., Riehl, H., Marasca, J.M., Effect of light irradiation on tooth whitening: enamel microhardness and color change (2009) J Esthet Restor Dent., 21, pp. 387-94Singh, R.D., Ram, S.M., Shetty, O., Chand, P., Yadav, R., Efficacy of casein phosphopeptide-amorphous calcium phosphate to prevent stain absorption on freshly bleached enamel: An in vitro study (2010) J Conserv Dent., 13, pp. 76-
Activated Random Walkers: Facts, Conjectures and Challenges
We study a particle system with hopping (random walk) dynamics on the integer
lattice . The particles can exist in two states, active or
inactive (sleeping); only the former can hop. The dynamics conserves the number
of particles; there is no limit on the number of particles at a given site.
Isolated active particles fall asleep at rate , and then remain
asleep until joined by another particle at the same site. The state in which
all particles are inactive is absorbing. Whether activity continues at long
times depends on the relation between the particle density and the
sleeping rate . We discuss the general case, and then, for the
one-dimensional totally asymmetric case, study the phase transition between an
active phase (for sufficiently large particle densities and/or small )
and an absorbing one. We also present arguments regarding the asymptotic mean
hopping velocity in the active phase, the rate of fixation in the absorbing
phase, and survival of the infinite system at criticality. Using mean-field
theory and Monte Carlo simulation, we locate the phase boundary. The phase
transition appears to be continuous in both the symmetric and asymmetric
versions of the process, but the critical behavior is very different. The
former case is characterized by simple integer or rational values for critical
exponents (, for example), and the phase diagram is in accord with
the prediction of mean-field theory. We present evidence that the symmetric
version belongs to the universality class of conserved stochastic sandpiles,
also known as conserved directed percolation. Simulations also reveal an
interesting transient phenomenon of damped oscillations in the activity
density
Assessing the Diversity of Sea Beet (Beta vulgaris L. ssp. maritima) Populations
Beta vulgaris L. subsp. maritima (L.) Arcang., sea beet, is a morphologically and genetically variable species, belonging to beet primary gene-pool. This crop wild relative is a valuable genetic resource for resistance improvement in beets and could play an important role in crop yield sustainability. Eleven Madeiran sea beet populations were characterized using morphological descriptors and genetic markers. Our goal was to evaluate these populations as a potential source of valuable genetic material. Morphological characterization showed a high quantitative variation among populations. Plant height and inflorescence height parameters had the highest influence in the separation of populations. Molecular analysis was performed with polymorphic SSRs to determine genetic variability between populations. Both PCA and PCoA revealed three clusters that separated the populations according to morphological and genetic traits, respectively. This study contributes to the knowledge of sea beet diversity in Madeira’s archipelago and to the perception that the islands' specific environmental conditions influence its genetic variability, making these populations a possible gene source for sugar beet breeding program
Onion yield under agroecological farming system using distinct irrigation depths and soil covers
Estimativa de ocorrência de precipitação em áreas agrícolas utilizando floresta de caminhos ótimos
Fusarium wilt incidence and common bean yield according to the preceding crop and the soil tillage system
- …