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761.
C. Borrego A. Monteiro E. Sá A. Carvalho D. Coelho D. Dias A. I. Miranda 《Water, air, and soil pollution》2012,223(8):5307-5320
Recently, specific air quality problems have been detected in the northern region of Portugal. The nitrogen oxide (NO2) annual limit value has been surpassed at several air quality monitoring stations in the northern region, and according to European legislation, air quality plans must be designed and implemented to reduce those levels. The analysis of the air quality data from the stations concerning NO2 exceedances indicates that traffic is responsible for an increase of more than 40?% compared with the urban background value. Specific measures to reduce NOx emissions have been selected and are related not only mainly to the traffic sector but also to the industrial and residential combustion sectors. The main objective of this study is to investigate the impact of the selected measures on the ambient levels of NO2 in northern Portugal using a numerical modelling tool??The Air Pollution Model (TAPM). TAPM was applied over the study region using a 120?×?120-km2 simulation domain and a spatial resolution of 4.8?×?4.8?km2. The entire year of 2010 was simulated and was set as the base year to analyse the impact of the selected measures. Two scenarios have been defined and simulated: the base situation, which considers current NOx emissions, and the reduction scenario for which NOx emissions were re-estimated considering the implementation of the measures. The modelling results demonstrate a decrease of 4?C5???g?m?3 in the annual NO2 levels in the study region. Moreover, the implementation of the selected measures will allow compliance with the NO2 annual limit values in three of the five air quality stations that measured levels surpassing those established by legislation. This situation demands additional measures that should be implemented at the local level and that particularly focus on the traffic sector. 相似文献
762.
In south east England climate change is predicted to include decreases in periodicity of rainfall events during summer, resulting in more, longer periods of drought. In many temperate regions these changes will affect foraging strategies of soil animals, including arthropod macro-decomposers such as terrestrial isopods. We investigated activity budgets under drier (50%) and moisture (90%) relative humidity conditions, for three species: Porcellio scaber, Oniscus asellus and Armadillidium vulgare, representing three families, which have different morphological adaptations to the terrestrial environment. In the drier environment all three species spent more time sheltering, less time feeding and less time in other activities. Costs of foraging were estimated by monitoring loss of body mass for 7 h. This loss was twice as high under the lower humidity regime. On the basis of morphological traits, two members of the Oniscidae: O. asellus and Philoscia muscorum, differing in eco-morphological strategies, were predicted to be more susceptible to desiccation than members of the Porcellionidae or Amadillidiidae. Members of the Oniscidae lost mass most quickly and also suffered higher mortality in the drier atmosphere. A cost of spending more time sheltering was that consumption of high quality food by Porcellio scaber was significantly reduced in the drier environment. The trade-off between energy gain by feeding and increased probability of survivorship by sheltering, is illustrated using an isopleth model. Changes in the extent to which the soil fauna will stimulate microbial metabolism and hence soil carbon dioxide emissions, under future conditions of climate change are predicted. 相似文献
763.
Jaramillo Colorado BE Martelo IP Duarte E 《Journal of agricultural and food chemistry》2012,60(25):6364-6368
The chemical composition of essential oils isolated from aerial parts of Triphasia trifolia (Burm. f.) P. Wilson was analyzed using hydrodistillation by GC-MS. The main constituents found were β-pinene (64.36%), (+)-sabinene (8.75%), hexadecanoic acid (6.03%), α-limonene (4.24%) and p-cymene (2.73%). The essential oil from T. trifolia shows high antioxidant potential (94.53%), an effect that is comparable with ascorbic acid (96.40%), used as standard. In addition, these oils had high repellent effects on the insect Tribolium castaneum Herbst (99% ± 1) at 0.2 μL/cm(2) after 2 h of exposure. 相似文献
764.
Lira NS Montes RC Tavares JF da Silva MS da Cunha EV de Athayde-Filho PF Rodrigues LC da Silva Dias C Barbosa-Filho JM 《Marine drugs》2011,9(11):2316-2368
Aplysina is the best representative genus of the family Aplysinidae. Halogenated substances are its main class of metabolites. These substances contribute greatly to the chemotaxonomy and characterization of the sponges belonging to this genus. Due to their pharmacological activities, these alkaloids are of special interest. The chemistry of halogenated substances and of the alkaloids has long been extensively studied in terrestrial organisms, while the number of marine organisms studied has just started to increase in the last decades. This review describes 101 halogenated substances from 14 species of Aplysina from different parts of the world. These substances can be divided into the following classes: bromotyramines (A), cavernicolins (B), hydroverongiaquinols (C), bromotyrosineketals (D), bromotyrosine lactone derivatives (E), oxazolidones (F), spiroisoxazolines (G), verongiabenzenoids (H), verongiaquinols (I), and dibromocyclohexadienes (J). A compilation of their (13)C NMR data is also part of the review. For this purpose 138 references were consulted. 相似文献
765.
766.
Wilson M Furuya Luiz E Pezzato Margarida M Barros A C Pezzato Valéria R B Furuya & Edma C Miranda 《Aquaculture Research》2004,35(12):1110-1116
This study was undertaken in a closed system with Nile tilapia (Oreochromis niloticus) to examine the effects of total replacement of fish meal (FM) by soybean meal. Nile tilapia fingerlings with an average weight of 5.34±0.08 g were hand‐fed one of the five isoenergetic (≈13.5 MJ digestible energy kg?1) and isoproteic (≈31% of digestible protein) experimental diets to satiation, six times a day during 85 days in eight replicate fibreglass tanks (six fish per tank). The control diet containing FM was substituted by soybean meal, with and without essential amino acids (lysine, methionine and threonine) or dicalcium phosphate supplementation. The supplemental amino acids were added at levels to simulate the reference amino acid profile of Nile tilapia carcass protein, based on the ideal protein concept. The results showed that soybean meal diet supplemented only with dicalcium phosphate was inferior to the control diet with FM and soybean meal diets supplemented with dicalcium phosphate and essential amino acids. Multiple essential amino acids and dicalcium phosphate incorporation in soybean meal diets was associated with performance, whole‐body composition and carcass yield equal to that of the fish fed with the control diet containing FM. These data suggest that a diet with all plant protein source, supplemented with essential amino acids, based on tissue amino acid profile, can totally replace FM in a diet for Nile tilapia, without adverse effects on the growth performance, carcass yield and composition. 相似文献
767.
The pine wood nematode Bursaphelenchus xylophilus (Steiner et Buhrer) Nickle is the causal agent of pine wilt disease. We evaluated the efficacy of emamectin benzoate (EB) for preventing wilt disease in the field and its effect on the vector Monochamus galloprovincialis (Olivier) (Coleoptera: Cerambycidae). Four experimental plots were delimited in a maritime pine (Pinus pinaster Aiton) forest in Portugal. Trunk-injection trials with EB included three dose-rates: 0.032 g a.i. cm?1 diameter at breast height—DBH, n?=?75 trees; 0.064 g a.i. cm?1 DBH, n?=?75 trees; and 0.128 g a.i. cm?1 DBH, n?=?50 trees; along with an untreated control plot (n?=?75 trees). EB was successfully injected and translocated in pines at an effective concentration. None of the treated trees died after a period of 26 months, contrasting with a 33% mortality of non-treated pines. Analysis of residues successfully detected EB in branches of treated pines, with the quantity increasing relative to the injection dose rate, and was found to have a clear effect on the longevity and feeding activity of adult M. galloprovincialis feeding on branches. EB was efficient in preventing wilt disease and bark beetle attacks in the terrain, and its application by trunk injection is a new option for wilt disease management programs in Portugal and in Europe. 相似文献