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101.
102.
Marta Lizandra do Reo Leal Emmanuel Veiga de Camargo Daniel Henrique Ross Marcelo Beltrão Molento Sonia Terezinha dos Anjos Lopes João Batista Teixeira da Rocha 《Veterinary research communications》2010,34(6):549-555
The objective of this study was to evaluate oxidative stress in lambs experimentally infected with Haemonchus contortus and supplemented with selenium and vitamin E. Twenty male Corriedale lambs were divided into four experimental groups with
five animals each: G1 consisted of animals infected and supplemented with 0.2 mg/kg of live weight (LW) sodium selenite by
intramuscular injection (IM); G2 consisted of animals infected with larvae and supplemented with 0.2 mg/kg LW sodium selenite
IM and 2000 IU per animal of Vitamin E IM; G3 consisted of animals infected with larvae and supplemented with 2000 IU per
animal of Vitamin E IM; and G4 consisted of animals infected with larvae. The animals were infected orally with 500 H. contortus larvae (L3) every 48 hours for 20 days. For biochemical analyses and eggs per grams of feces (EPG) evaluation, blood and
feces were both collected at zero (T0), 20 (T1), 40 (T2) and 60 (T3) days. The weight of the animals was also measured at
these times. Lower TBARS values were observed in the supplemented animals compared to the control group. The groups supplemented
with Selenium exhibited blood GSH-Px activity higher than that of non-supplemented animals. Supplementation with selenium
provided greater antioxidant protection against oxidative stress generated from experimental infection of lambs with H. contortus. 相似文献
103.
Jaqueline Magalhães Pereira Edson Luiz Lopes Baldin Everton Pires Soliman Carlos Frederico Wilcken 《Phytoparasitica》2013,41(2):117-124
The red gum lerp psyllid Glycaspis brimblecombei Moore (Hemiptera: Psyllidae) was first recorded in Brazil in 2003 and since then has caused serious damage in Eucalyptus forests. The damage is mainly due to defoliation, sooty mold and dieback, thus requiring the development of efficient management strategies. The settling and ovipositional preference of G. brimblecombei by species and clones of Eucalyptus were evaluated in free- and no-choice tests. Preliminary tests were done to determine the density of psyllid couples that produced the greatest densities of eggs, leaf position selection for oviposition, and whether oviposition was affected by preimaginal conditioning. Apical leaves were used more frequently for oviposition by the psyllid, and the number of eggs decreased from the apex to the base. The densities of 10 and 15 psyllid couples per seedling produced the highest oviposition. There was no evidence of preimaginal conditioning. In the free-choice test, E. grandis, E. urophylla, VM-1, I-144, C-219 and H-13 were less attractive to G. brimblecombei adults, with H-13, E. grandis and E. urophylla having the least oviposition. In the no-choice test, E. urophylla, GG-100 and E. grandis also demonstrated a lower oviposition, but E. camaldulensis and 3025 were highly susceptible. The low preference for the genotypes E. grandis and E. urophylla suggests the occurrence of a non-preference type resistance against the red gum lerp psyllid. Our results can be utilized for the development of management programs for G. brimblecombei in Eucalyptus forests. 相似文献
104.
Removal of Arsenic from Aqueous Solutions by Sorption onto Sewage Sludge-Based Sorbent 总被引:1,自引:0,他引:1
Daniela S. Tavares Cláudia B. Lopes Jo?o P. Coelho Marta E. Sánchez Ana I. Garcia Armando C. Duarte Marta Otero Eduarda Pereira 《Water, air, and soil pollution》2012,223(5):2311-2321
This study aimed at evaluating and comparing the removal of arsenic from solutions by a low-cost waste-based sorbent, produced by pyrolysing sewage sludge under appropriate conditions, and by a commercially activated carbon. Batch sorption experiments were performed under isothermal conditions (20°C), in order to evaluate the effect of pH on the arsenic sorption kinetics and on the equilibrium sorption capacity of the materials under study. Kinetic data revealed that the arsenic sorption was faster onto the activated carbon than onto the pyrolysed sludge. The sorption process was well described by both the pseudo-first and pseudo-second-order kinetics equations for both materials. Changes in the initial solution pH have distinct effects on the removal of arsenic onto pyrolysed sludge and activated carbon. While for pyrolysed sludge, pH affects essentially the equilibrium time, for activated carbon it affects the sorption capacity. Equilibrium results were well described by both Freundlich and Langmuir isotherm models, although fittings corresponding to the Langmuir isotherm were slightly better. The Langmuir maximum sorption capacity determined for the pyrolysed sludge was 71???g?g?1, while for activated carbon was 229???g?g?1. Despite the relative lower capacity of the pyrolysed sludge, the considerable lower cost and the valorisation of the sludge may justify further research on its use for water decontamination. 相似文献
105.
Enio Tarso de Souza Costa Luiz Roberto Guimarães Guilherme Guilherme Lopes Nilton Curi 《Water, air, and soil pollution》2012,223(4):1661-1670
Assessing multielement adsorption of trace metals on materials having potential to be used as soil amendments is an essential
stage for the remediation success, as soil contamination rarely occurs with a single element. This study evaluated mono-/multielement
adsorption of Zn, Cu, Cd, and Pb on aluminum (AMB) and iron mining by-products (IMB, used for comparison). Prior to adsorption,
these products were characterized by X-ray diffraction, isoelectric point, infrared spectroscopy, scanning electron microscopy,
and microwave furnace digestion. Sorption experiments comprised: (1) pH adjustment (5.5, 6.5, and natural suspension pH),
(2) mono- and multielement adsorption, and (3) desorption. Rising pH from 5.5 to natural suspension values (9.5) increased
monoelement adsorption of Zn, Cu, Cd, and Pb on AMB up to 3.8-, 1.4-, 6.2-, and 1.1-fold, whereas multielement adsorption
was increased up to 17.3-, 2.0-, 20.3-, and 1.2-fold, respectively. Zinc and Cd were less adsorbed than Cu and Pb and more
affected by competition. Multielement adsorption at 5.5 pH in AMB resulted in smaller adsorption of Zn (up to 4.6-fold), Cu
(1.4-fold), Cd (3.3-fold), and Pb (1.1-fold) when compared with monoelement adsorption. The lower the pH, the smaller the
adsorption and the higher the desorption. The AMB showed higher capacity to maintain the elements adsorbed than the IMB. 相似文献
106.
Paulo Renato Matos Lopes Renato Nallin Montagnolli Ederio Dino Bidoia 《Water, air, and soil pollution》2012,223(7):3673-3688
Electrochemical processes in industrial effluents have been studied as a means to obtain higher efficiency in wastewater treatment. Heterogeneous photocatalysis appears as a low-cost alternative through the use of lower wattage lamps and thermal TiO2 films. Photocatalysis became a clean process for water treatment due to hydroxyl radicals generated on semiconductor surface. Such radicals are able to degrade several organic compounds. This study used different electrodes and analytical methods for degradation of phenol molecules to reduce treatment costs, improve efficiency, and identify compounds formed during the decomposition of phenolic molecules. Thermal growth of TiO2 film was observed on the titanium electrode in rutile form. Application of an electrical potential on the Ti/TiO2 working electrode increases efficiency in reducing concentration of phenol after photocatalytic treatment. Still, high energy radiation (UVC) showed best degradation rates in photolytic process. Different compounds formed during the degradation of phenol were also identified in the UVC?CPE treatment. 相似文献
107.
I. N. Kurganova V. O. Lopes de Gerenyu J. F. Gallardo Lancho C. T. Oehm 《Eurasian Soil Science》2012,45(1):68-79
The processes of the organic matter (OM) mineralization in forest soils developed under temperate continental (Moscow oblast,
Russia), Mediterranean (the central and western parts of Spain), and tropical monsoon (southern Vietnam) climates were studied
under laboratory conditions. The potential and specific rates of the OM mineralization (PR
min and PR
min/Corg, respectively), the ecophysiological parameters of the microbial communities status (Cmic, qCO2, and Cmic/Corg), and the sensitivity of the rate of the OM mineralization to the rise in temperature were evaluated by the temperature coefficients
(Q
10) determined in the humus horizons (0–10 cm, without forest litter). The average values of PR
min for the climatic zones decreased in the following order: Mediterranean (57.1 ± 10.6 mg C/kg per day) > temperate continental
(23.8 ± 7.1 mg C/kg per day) > tropical monsoon (10.4 ± 1.6 mg C/kg per day). The lowest resistance of the soil OM to mineralization
as evaluated by the PR
min/Corg values was found in the Albeluvisol and Phaeozem of the temperate continental climate and in the Acrisol of the Mediterranean
climate. The highest Q
10 coefficients were attributed to the OM mineralization in the forest soils of the temperate continental climate. This allowed
us to conclude that the observed and expected climate changes with an increase in the mean annual air temperature should lead
to the maximum intensification of the OM mineralization processes in the forest soils of northern regions. 相似文献
108.
Marc Babut Christelle Lopes Sébastien Pradelle Henri Persat Pierre-Marie Badot 《Journal of Soils and Sediments》2012,12(2):241-251
Purpose
Since 2005, freshwater fish contamination by polychlorobiphenyls (PCBs), polychlorodibenzodioxins, and polychlorodibenzofurans has been assessed in the Rhone River basin (France). A large database of surface sediment contamination by PCBs is also available, opening the way to the study of biota-to-sediment accumulation factor (BSAF) distribution throughout this basin. The ultimate goal of the study was to determine a sediment quality guideline (SQG) corresponding to the regulatory fish consumption limit. 相似文献109.
Serão NV Veroneze R Ribeiro AM Verardo LL Braccini Neto J Gasparino E Campos CF Lopes PS Guimarães SE 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2011,128(1):28-34
Seventy-two pigs of three genetic groups (Brazilian indigenous breed Piau, Commercial line and Crossbred) of both sexes were slaughtered at four live weights (30, 60, 90 and 120 kg). Intramuscular fat (IMF) content in Longissimus dorsi muscle of each animal was extracted and correlated with candidate gene mRNA expression (ATN1, EEF1A2, FABP3, LDLR, MGP, OBSCN, PDHB, TRDN and RYR1). Within slaughter weight of 120 kg, Piau and Crossbred pigs showed higher IMF content (p < 0.05) than commercial animals, with 2.48, 2.08 and 1.00% respectively. Barrows presented higher values of IMF (p < 0.05) than gilts (1.54 and 1.30% respectively). Gene expression of EEF1A2, FABP3, LDLR, OBSCN, PDHB, TRDN and RYR1 were correlated with IMF (p < 0.05) using the whole dataset. For Piau data only, expression of FABP3, LDLR, MGP, OBSCN, PDHB, TRDN and RYR1 showed correlation with IMF (p < 0.05). Genes that have important roles in lipid transportation inside the cell (FABP3) and tissues (LDLR) showed correlation with IMF of, respectively, 0.68 and 0.63 using the whole data set, and 0.90 and 0.91 using data from Piau animals. The highly positive correlation of the LDLR and FAPB3 expression with IMF content may confirm that these genes are important for fat deposition in the porcine L. dorsi muscle. 相似文献
110.
Duarte Mde S Paulino PV Valadares Filho Sde C Paulino MF Detmann E Zervoudakis JT Monnerat JP Viana Gda S Silva LH Serão NV 《Tropical animal health and production》2011,43(4):877-886
The effects of two levels of concentrate and ruminally undegradable protein (RUP) on performance, intake, digestibility, carcass
characteristics, meat quality traits, and commercial cuts yield were assessed. Twenty crossbred heifers (240 kg average body
weight) were used. At the beginning of the trial, four animals were slaughtered as reference group and the 16 remaining animals
were randomly assigned to four treatments, in a 2 × 2 factorial design: two levels of concentrate (40% and 80%, dry matter
(DM) basis) and two levels of RUP (48.79% and 27.19% of CP). At the end of the trial, all the animals were slaughtered. There
was no interaction (P > 0.05) between concentrate and RUP levels. Dry matter intake and nutrients digestibility was not affected (P > 0.05) by RUP level. Heifers fed the highest RUP level had greater (P < 0.05) average daily gain (ADG). Concentrate level did not affect (P > 0.05) DMI and ADG. Heifers fed diets with 80% concentrate had greater intake of TDN and EE, and lower intake of NDF (P < 0.05). The digestibilities of all nutrients, except the NDF, were greater (P < 0.05) for the 80% concentrate diets. The RUP levels did not affect (P > 0.05) the carcass characteristics and carcass gain composition. Heifers fed 80% concentrate diets had larger (P < 0.05) longissimus muscle area and lower gain of bones (P < 0.05). Concentrate level did not affect (P > 0.05) the composition of carcass gain. There was no effect (P > 0.05) of RUP and concentrate levels on meat quality traits and commercial cut yields. 相似文献