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排序方式: 共有355条查询结果,搜索用时 15 毫秒
61.
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
62.
Development of an indirect ELISA-NcSRS2 for detection of Neospora caninum antibodies in cattle 总被引:1,自引:0,他引:1
Borsuk S Andreotti R Leite FP Pinto Lda S Simionatto S Hartleben CP Goetze M Oshiro LM Matos Mde F Berne ME 《Veterinary parasitology》2011,177(1-2):33-38
Neosporosis is of alarming economic concern in the cattle industry. The effectiveness of diagnostic tests for detecting specific antibodies against Neospora caninum is hampered by potential cross-reaction with other coccidia. Use of a single specific antigen might improve test specificity. An indirect enzyme-linked immunosorbent assay (ELISA) was developed using the truncated protein NcSRS2 expressed in Escherichia coli. The ELISA results were compared with those of the indirect fluorescence antibody test (IFAT). Receiver Operating Characteristic (ROC) and Tests in the Absence of a Gold Standard (TAGS) analysis revealed an assay having 96% specificity and 95% sensitivity when applied to 145 positive and 352 negative sera from two distinct cattle populations. Using OD ≤ 0.095 as the cut-off point, the assay's negative and positive predictive values ranged from 98.8% to 50.8% and from 58.8% to 99.1%, respectively, depending on neosporosis prevalence in a given area. The novel ELISA-NcSRS2 format described in the present report constitutes a specific and sensitive method for detecting N. caninum in cattle. 相似文献
63.
Marcos Antonio Camacho da Silva William Natale Renato de Mello Prado Márcio Koiti Chiba 《Journal of plant nutrition》2013,36(4):694-702
ABSTRACT Citrus cultures have a fundamental importance to the Brazilian economy; certain aspects such as plant nutrition, yield, and fruit quality are vital for the citrus industry sustainability. The present study evaluated the nutritional status of manganese in adult Pear orange trees using different lime rates topically applied to the soil. The direct evaluation of lime rates effects on leaf manganese (Mn) levels revealed a decrease of the nutrient correlated to its increased, as well as passage of time between application and measurement. Foliar sampling 30 months after surface lime application evidenced a high correlation of foliar manganese levels with soil base saturation of 10–20 cm. Leaf manganese levels which showed a great probability of high productivity were between 33 and 70 mg kg?1. 相似文献
64.
The low-molecular-weight glutenin subunits of wheat gluten 总被引:11,自引:0,他引:11
Low-molecular-weight glutenin subunits (LMW-GS) are polymeric protein components of wheat endosperm and like all seed storage proteins, are digested to provide nutrients for the embryo during seed germination and seedling growth. Due to their structural characteristics, they exhibit features important for the technological properties of wheat flour. Their ability to form inter-molecular disulphide bonds with each other and/or with high-molecular-weight glutenin subunits (HMW-GS), is important for the formation of the glutenin polymers, which are among the biggest macromolecules present in nature, and determine the processing properties of wheat dough. Explanation of the structural basis for these correlations continues to intrigue researchers and, while earlier emphasis had been on HMW-GS, considerable attention is now being focused on the LMW-GS.LMW-GS are a highly polymorphic protein complex, including proteins with gliadin-type sequences. Difficulty in separating single components, arising from the complexity of the group, has limited the characterisation of the individual proteins and the establishment of clear-cut relationships with quality parameters.Here we review results concerning different aspects of LMW-GS, including their structural characteristics, genetic control, and relationships with quality parameters. In addition, we emphasise the distinction between the components with sequences unique to the LMW-GS fraction and those behaving like glutenin subunits (incorporated into polymers), but with sequences corresponding to gliadins. 相似文献
65.
J. Renato de Freitas 《Pedobiologia》2000,44(2)
The effects of bacterial inoculants on the growth of winter wheat were studied in a growth chamber. Azospirillum brasilense, Azotobacter chroococcum, Bacillus polymyxa, Enterobacter cloacae, or a mixture of the four rhizobacteria were the inoculants tested. Inoculation effects on yield, yield components, and N-derived from fertilizer (Ndff) were assessed. The response of plants inoculated with individual bacteria was inconsistent and varied with treatment. At the first harvest (58 days after planting-DAP) plants inoculated with the mixture exhibited increases in plant dry weight, total-N and Ndff. At the second harvest (105 DAP), plants inoculated with A. brasilense and the mixture exhibited increases in shoot biomass, whereas at maturity (170 DAP), the inoculated plants showed no differences in total-N or shoot dry matter yield, as compared to the uninoculated controls. Inoculation with A. brasilense, however, increased the Ndff in the shoots, and B. polymyxa tended to enhance grain yield. Practical use of these rhizobacteria as inoculants for winter wheat may have limited value until such time as we better understand factors which influence rhizosphere competence of bacterial inoculants. 相似文献
66.
Garofalo NA Teixeira Neto FJ Alvaides RK de Oliveira FA Pignaton W Pinheiro RT 《Veterinary anaesthesia and analgesia》2012,39(4):324-334
ObjectiveTo evaluate the agreement between invasive blood pressure (IBP) and Doppler ultrasound blood pressure (DUBP) using three cuff positions and oscillometric blood pressure (OBP) in anesthetized dogs.Study designProspective study.AnimalsNine adult dogs weighing 14.5–29.5 kg.MethodsThe cuff was placed above and below the tarsus, and above the carpus with the DUBP and above the carpus with the OBP monitor. Based on IBP recorded via a dorsal pedal artery catheter, conditions of low, normal, and high systolic arterial pressures [SAP (mmHg) <90, between 90 and 140, and >140, respectively] were induced by changes in isoflurane concentrations and/or dopamine administration. Mean biases ± 2 SD (limits of agreement) were determined.ResultsAt high blood pressures, regardless of cuff position, SAP determinations with the DUBP underestimated invasive SAP values by more than 20 mmHg in most instances. With the DUBP, cuff placement above the tarsus yielded better agreement with invasive SAP during low blood pressures (0.2 ± 16 mmHg). The OBP underestimated SAP during high blood pressures (?42 ± 42 mmHg) and yielded better agreement with IBP for mean (MAP) and diastolic (DAP) arterial pressure measurements [overall bias: 2 ± 15 mmHg (MAP) and 0.2 ± 16 mmHg (DAP)].ConclusionsAgreement of SAP determinations with the DUBP is poor at SAP > 140 mmHg, regardless of cuff placement. Measurement error of the DUBP with the cuff placed above the tarsus is clinically acceptable during low blood pressures. Agreement of MAP and DAP measurements with this OBP monitor compared with IBP was clinically acceptable over a wide pressure range.Clinical relevanceWith the DUBP device, placing the cuff above the tarsus allows reasonable agreement with IBP obtained via dorsal pedal artery catheterization. Only MAP and DAP provide reasonable estimates of direct blood pressure with the OBP monitor evaluated. 相似文献
67.
Liveri ML Sciascia L Lombardo R Tesoriere L Passante E Livrea MA 《Journal of agricultural and food chemistry》2007,55(8):2836-2840
The solubilization site of two betalain pigments, namely, betanin and indicaxantin, into l-alpha-dipalmitoyl-phosphatidylcholine (DPPC) and dimyristoylphosphatidylcholine (DMPC) vesicles was investigated by a spectrophotometric study. Pigment absorbance was monitored by varying phospholipid concentration, at a constant temperature that was varied in a range including the main phase transition temperature (Tm) of the relevant phospholipid bilayer. Maximum betanin absorption increased with the increase of DPPC concentration within the entire temperature range, reaching a plateau. The binding constant (Kb) of the pigment, calculated according to a pseudo-two-phase model, varied with the temperature, indicating that betanin is located at the hydrophobic interior of the bilayer. Other measurements of binding of betanin to DMPC and of indicaxanthin to either DPPC or DMPC vesicles ruled out that these compounds were solubilized in the hydrophobic interior of these bilayers. 相似文献
68.
Trypanocidal Action of (?)-Elatol Involves an Oxidative Stress Triggered by Mitochondria Dysfunction
Vania Cristina Desoti Danielle Lazarin-Bid��ia Daniela Bueno Sudatti Renato Crespo Pereira Antonio Alonso Tania Ueda-Nakamura Benedito Prado Dias Filho Celso Vataru Nakamura Sueli de Oliveira Silva 《Marine drugs》2012,10(8):1631-1646
Natural compounds have shown good potential for the discovery of new chemotherapeutics for the treatment of Chagas’ disease. Recently, our group reported the effective trypanocidal activity of (−)-elatol, extracted from the red macroalgae Laurencia dendroidea present in the Brazilian coast against Trypanosoma cruzi. However, the mechanism of action of this compound has remained unclear. There are only hypotheses concerning its action on mitochondrial function. Here, we further investigated the mechanisms of action of (−)-elatol on trypomastigotes of T. cruzi. For this, we evaluated some biochemical alterations in trypomastigotes treated with (−)-elatol. Our results show that (−)-elatol induced depolarization of the mitochondrial membrane, an increase in the formation of mitochondrial superoxide anion and loss of cell membrane and DNA integrity. Additionally, (−)-elatol induced formation of autophagic vacuoles and a decrease in cell volume. All together, these results suggest that the trypanocidal action of (−)-elatol involves multiple events and mitochondria might be the initial target organelle. Our hypothesis is that the mitochondrial dysfunction leads to an increase of ROS production through the electron transport chain, which affects cell membrane and DNA integrity leading to different types of parasite death. 相似文献
69.
We describe the development and distribution of intestinal aminopeptidase M, dipeptidyl aminopeptidase IV, non-specific esterase, alkaline phosphatase and acid phosphatase, using enzyme histochemistry techniques, in the spotted sand bass larvae ( Paralabrax maculatofasciatus ) under culture conditions. All digestive enzymes tested showed a positive reaction from first feeding (day 2) and throughout the study period (day 30). At first feeding, the main enzymatic activity was in the mucosa throughout the intestines. Later, enzymatic activity occurred in the liver, kidney and stomach. All enzymatic activities increased from days 15 to 20, remaining constant until the end of the study. This enzymatic activity suggests the onset of maturation of the digestive tract. After day 20, a positive reaction was recorded in the pyloric caeca for all tested enzymatic activities. Our study confirms the digestive and absorptive functions in the intestines in spotted sand bass larvae from first feeding. It also brings new insight to establish an early weaning strategy during cultivation of spotted sand bass larvae. 相似文献
70.
Jorge Hernández Iker Uriarte María Teresa Viana Renato Westermeier & Ana Farías 《Aquaculture Research》2009,40(15):1694-1702
A feeding experiment was carried out to evaluate two natural diets versus a formulated feed on the performance of weaning red abalone Haliotis rufescens . Four treatment diets were then investigated: a formulated diet; plantlets from culture Macrocystis pyrifera, Porphyra columbina from natural beds; and a mixed diet consisting of a blend of fresh P. columbina together with the formulated diet. This study was performed in a shallow aquaculture system with a horizontal water flow. After 90 days, significant differences were observed between treatments. The highest growth was obtained with Porphyra (3.3 mm month−1 ), followed by the mixed diet (2.6 mm month−1 ), then Macrocystis (2.1 mm month−1 ) and lastly the formulated diet (1.4 mm month−1 ). Moreover, after the diets were tested for stability and remnant nutrients after a 12-h water immersion, a positive trend appeared to be related to the protein/energy (P:E). It is concluded that fronds of P. columbina resulted in the best diet for weaning H. rufescens under horizontal water flow systems, even if apparently the water stability of the formulated diet had a negative impact on abalone performance, particularly due to a poor nutrient retention capacity. Therefore, formulated diets should be improved before being recommended for weaning red abalone. 相似文献