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51.
Alejandro Ruiz-Marín Silvia Campos-Garcia José Zavala-Loría Fernando Solana Yunuen Canedo-López 《Water, air, and soil pollution》2009,199(1-4):13-21
A simultaneous treatment of BOD, phosphorous and ammonia in artificial wastewater was carried out in biofilm reactors with Luffa cylíndrica as organic support and compared with PVC's support under variations of dissolved oxygen of 1.5 a 3.0 mg l?1 in the same reactor. During semicontinous treatment, the removal of BOD (92.5%) with Luffa cilíndrica was higher than PVC support (80%). Nitrification only existed at levels of oxygen of 3 mg l?1, showed in the effluent a final concentration of ammonium of 17 and 19 mg l?1 for Luffa cilíndrica and PVC support, respectively. In reactors with Luffa cilíndrica a higher percentage of P removal (40%) was reached, while no elimination in reactors with PVC was observed. The formation of anaerobic-aerobic zones inside the natural support probably allowed the increase in the efficiency of removal of phosphorous. Oxidation of organic matter, P removal and nitrification can be achieved with the variation of oxygen inside of the same biofilm reactor using L. cylindrical as support material. 相似文献
52.
Aline Medeiros de Paula Mendes Dulciene Karla de Andrade Silva Marcelo de Andrade Ferreira Antonia Sherlânea Chaves Veras Geane Dias Gonçalves Ferreira Ricardo Brauer Vigoderis Helton Gregory Santos Arcanjo Jarbas Miguel Silva Jr. Josimar Santos de Almeida Anna Christine Alencar Fotius Glébio de Almeida Farias 《Tropical animal health and production》2012,45(1):231-237
The aim of this study was to assess the effect of different supplements on the behavior variables of crossbred dairy cows that were in pasture that comprised two 4?×?4 Latin squares (four periods, four treatments, and four animals). Each experimental period lasted 15 days (10 days to adapt animals to treatments and 5 days for data collection). The animals were supplemented twice a day, with different forage (corn silage and cactus pear) and concentrate sources (soy mea + wheat meal + corn meal + cotton seed together and soy meal as a single constituent of the concentrate). A significant difference (p?<?0.10) was observed for the percentage of time spent consuming the supplement and for idleness, rumination, and bite rate at the time of supplementation. The supplement intake period was greater for the cactus pear-based supplements due to the lower dry matter content. Those based on corn silage resulted in longer rumination periods than those consisting of cactus pear; however, the opposite was observed for supplements based on the cactus, which showed higher percentages of time for idleness. The supplementation influenced the ingestive behavior of crossbred dairy cows. 相似文献
53.
Alla Shvaleva Filipe Costa e Silva Paula Scotti Mouhssin Oufir Jean-François Hausman Guignard Cedric Paula Ramos M. Helena Almeida M. Lucília Rodrigues João S. Pereira M. Manuela Chaves 《Annals of Forest Science》2008,65(2):204-204
We have compared the metabolic responses of leaves and roots of two Eucalyptus globulus L. clones CN5 and ST51 that differ in their sensitivity to water deficits (ST51 is more drought sensitive), with regard to the effect of chilling (10/5 °C, day/night). We studied changes in growth, osmotic potential and osmotically active compounds, soluble proteins, leaf pigments, and membrane lipid composition. Our data showed that both clones have the ability to acclimatize to chilling temperatures. As a result of 10 days of acclimation, an increase of soluble sugars in leaves of treated plants of both clones was observed that disappeared later on. Differences between clones were observed in the photosynthetic pigments and soluble protein content which were more stable in CN5 under chilling. It also was apparent that CN5 presented a less negative predawn water potential (ψpd) and a higher leaf turgor than ST51 throughout the chilling treatment. In the case of the CN5, increased total lipids (TEA) and concomitant increase of linolenic acid (C18:3) in leaves after acclimatization may be related to a better clone performance under chilling temperatures. Moreover, a higher constitutive investment in roots in the case of CN5 as compared to ST51 may benefit new root regeneration under low temperatures favoring growth after cold Mediterranean winter. 相似文献
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56.
Exterkoetter Ronan Rozane Danilo Eduardo da Silva Walquiria Chaves Toci Aline Theodoro Cordeiro Gilcelia Aparecida Benassi Simone Frederigi Boroski Marcela 《Journal of Soils and Sediments》2019,19(5):2240-2250
Journal of Soils and Sediments - Glyphosate is the world’s most used herbicide and monitoring glyphosate in the environment is a relevant topic. The present study aims to develop a... 相似文献
57.
Barbara Chaves Stefaan De Neve Maria del Carmen Lillo Cabrera Pascal Boeckx Oswald Van Cleemput Georges Hofman 《Biology and Fertility of Soils》2005,41(6):411-418
Manipulating the N release from high-N crop residues by simultaneous mixing of these residues with organic biological waste (OBW) materials seems to be a possible method to reduce NO3– leaching. The aim of this study was to examine whether the incorporation of OBW materials together with a high-N crop residue (celery) had also an effect on N2O emission from horticultural soil under short-term and optimised laboratory conditions. A sandy loam soil and celery residues were mixed with different OBW materials and brought into PVC tubes at 80% water-filled pore space and 15°C. Every 2.5 h, a gas sample was taken and analysed by gas chromatography for its N2O concentration. The soil amended with only celery residues had a cumulative N2O emission of 9.6 mg N kg–1 soil in 50 h. When the celery residues were mixed with an OBW material, the N2O emission was each time lower than the emission from the celery-only treatment (between 3.8 and 5.9 mg N kg–1 soil during maximum 77 h), except with paper sludge (17.2 mg N kg–1 soil in 100 h). The higher N2O emission from the paper sludge treatment was probably due to its unusually low C:N ratio. Straw, green waste compost 1 (GWC1) and 2 (GWC2), saw dust, and tannic acid reduced the N2O emission of the celery treatment by 40 to 60%. Although the N2O reduction potential can be expected to be lower and with differing dynamics under field conditions, this study indicates that apart from reducing NO3– leaching, OBW application may at the same time reduce N2O emissions after incorporation of high-N crop residues. 相似文献
58.
Gildacio Pereira Chaves Filho Lucas Alighieri Neves Costa Batista Silvia Regina Batistuzzo de Medeiros Hugo Alexandre Oliveira Rocha Susana Margarida Gomes Moreira 《Marine drugs》2022,20(8)
Sulfated polysaccharides (SPS) from seaweeds have great biochemical and biotechnological potential. This study aimed to investigate the effect of SPS isolated from the seaweed Caulerpa sertularioides on adipogenic differentiation as a possible alternative treatment for obesity. The SPS-rich extract from the seaweed C. sertularioides was fractioned into three SPS-rich fractions (F0.5; F0.9; and F1.8) chemically characterized. Among these four samples, only F0.9 showed a significant inhibitory effect on adipogenesis of 3T3-L1 preadipocytes. Ten SPS-rich fractions were isolated from F0.9 through ion-exchange chromatography. However, only the fraction (CS0.2) containing a sulfated glucan was able to inhibit adipogenesis. CS0.2 reduces lipid accumulation and inhibits the expression of key adipogenic (PPARγ, C/EBPβ, and C/EBPα) and lipogenic markers (SREBP-1c, Fabp4, and CD36). The data points to the potential of sulfated glucan from C. sertularioides for the development of functional approaches in obesity management. 相似文献
59.
Paulo Márcio Barbosa de Arruda Leite Robson Magno Liberal Véras Antonia Sherlânea Chaves Véras Adriana Guim Evaristo Jorge Oliveira de Souza Karla Katiene de Souza Silva Lígia Maria Gomes Barreto Janaina de Lima Silva Daniel Barros Cardoso 《Tropical animal health and production》2018,50(8):1807-1814
This aim of this study was to evaluate the intake and apparent digestibility of nutrients, ingestive behavior, blood parameters, and performance of lambs fed two roughage:concentrate (R:C) ratios, with or without liquid residue of cassava (LRC). Forty lambs (19.5?±?1.45 kg body weight) were distributed in a completely randomized 2?×?2 factorial design. The intake of dry matter (1311 g/day) and total digestible nutrients (755 g/day), and the intake (172 g/day) and digestibility (552 g/kg) of crude protein were higher for lambs fed R:C of 40:60. The R:C ratio of 80:20 promoted a higher intake (585 g/day) and digestibility (461 g/kg) of neutral detergent fiber. There was an intake of LRC of 1.37 L/day for lambs fed R:C of 80:20 and 0.42 L/day for lambs fed R:C of 40:60. The lambs fed R:C of 80:20 spent more time in feeding (326 m/day) and rumination (530 m/day). The metabolic profile and performance of lambs were not affected by LRC inclusion. The body weight gain (220 g/day) was higher in lambs fed R:C of 40:60. A roughage:concentrate ratio of 40:60 is recommended for lambs because it resulted in the best performance, regardless of supplementation with liquid residue of cassava. 相似文献
60.
Mendonça Fábio S. Nascimento Naiara C. F. Almeida Valdir M. Braga Thaiza C. Ribeiro Daniele P. Chaves Hisadora A. S. Silva Filho Givaldo B. Riet-Correa Franklin 《Tropical animal health and production》2018,50(3):693-696
Tropical Animal Health and Production - In the world, Kalanchoe species are primarily ornamentals and houseplants, but some have escaped cultivation and can be found in the field. In Latin America,... 相似文献