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961.
Paracetamol is an antipyretic analgesic widely used globally. It has been recurrently found in water bodies and is known to elicit toxic effects in aquatic species; however, its potential ability to induce oxidative stress in sentinel species remains unknown The objective was to establish a methodology to evaluate the toxicity elicited on the sentinel species Hyalella azteca by paracetamol-enriched sediment using oxidative stress tests. Concentrations used in assays were determined using the previously obtained median lethal concentration (72?h LC50). The following oxidative stress biomarkers were evaluated: lipid peroxidation (LPO), protein carbonyl content (PCC) in order to determine oxidized protein content, and the activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX). LPO and PCC increased significantly while SOD, CAT, and GPX decreased significantly (p?<?0.05) with respect to controls. Paracetamol induces oxidative stress on H. azteca, and the set of tests employed is helpful in evaluating the toxicity of this group of pharmaceuticals on aquatic species.  相似文献   
962.
Water, Air, &; Soil Pollution - We investigated the effects of four commercial formulations of herbicides (glyphosate [GLY], metsulfuron-methyl [MET], bispyribac-sodium [BIS], and picloram...  相似文献   
963.
Crop-water production functions (CWPFs) constitute a suitable tool for irrigation management in water-scarcity situations, and for estimating the yield response when a crop is subjected to long-term water stress. This work examines the long-term effects of different strategies of sustained deficit irrigation in mature sweet orange trees (Citrus sinensis L. Osb. cv. Salustiana). The trial was conducted from 2004 to 2010, with three deficit treatments imposed as a function of the water-stress index, which is defined as the ratio between the actual volume of water supply and the crop evapotranspiration rate. Crop-water production functions were evaluated for each year. Additionally, different yield-loss functions were defined on the basis of the impact of deficit irrigation for the entire study period. According to the findings, the crop response to water stress followed a clear trend over successive years, in which the time course of the yield loss showed an attenuated oscillation. Thus, the calculated yield-loss functions could be provided as an alternative tool for programming a long-term strategy of deficit irrigation under a water-scarcity situation.  相似文献   
964.
A cross-sectional study was carried out on equids (horses, mules and donkeys) in Andalusia, Southern Spain, to assess the level of exposure to equine piroplasmosis and to investigate risk factors associated with these infections. At least one animal seropositive for Theileria equi and/or Babesia caballi was detected in 222/380 (58.4%) herds sampled by competitive inhibition ELISAs. The seroprevalences for B. caballi and T. equi were 13.2% and 56.1%, respectively; there was serological evidence of co-circulation of both piroplasms in 10.8% of herds. Antibodies against equine piroplasms were detected in 286/537 (53.3%) animals; 61 (11.4%) were seropositive for B. caballi, 270 (50.3%) were seropositive for T. equi and 24 (8.4%) were seropositive for both T. equi and B. caballi.There was a significantly higher seroprevalence of B. caballi in mules (32.1%) compared with donkeys (17.0%) and horses (7.9%), and a significantly higher seroprevalence of T. equi in mules (66.1%) in comparison with horses (48.6%), but not donkeys (47.2%). There were significant differences in prevalence of both piroplasms among locations; the seroprevalence of B. caballi ranged from 0 to 22.5%, while the seropositivity to T. equi ranged from 26.7 to 63.3%. A multiple logistic regression model indicated that the risk factors associated with a higher T. equi seroprevalence were increased age, presence of ticks and vaccination against other diseases. Risk factors associated with a higher seroprevalence of B. caballi were species (mules compared to horses), entry of horses in the last 6 months, presence of ticks and presence of shelter. The findings indicate widespread exposure to equine piroplasmosis in Southern Spain.  相似文献   
965.
To compare an injectable progesterone (MAD-4) with an intravaginal device (IPD), and natural O17 with synthetic oestradiol (OB) in a synchronisation protocol, 51 cows were divided into four groups. Each group was treated with one of the two sources of progesterone and one of the two oestradiol formulations. Oestrus behaviour, follicle diameter, and pregnancy rates were evaluated. Oestrus behaviour (p = 0.902), numbers of cows in oestrus (p = 0.917), follicle diameter (p = 0.416), and pregnancy rates (p = 0.873) were similar among the four groups. More cows in the group treated with the IPD and OB scored > 200 oestrus behaviour points compared to the other groups (p = 0.038). A longer interval between the end of treatment and oestrus was observed among cows treated with MAD-4 than cows given the IPD (p = 0.030), but no differences were found between animals receiving the two oestradiol formulations (OB and O17). While the use of MAD-4 requires further testing, similar responses to natural oestradiol observed in the present study could allow the use of this formulation in reproductive protocols because it is not associated with the potential human health risks of OB.  相似文献   
966.
Heartwood is the most valuable part of larch timber when either natural durability or aesthetic aspects of the wood are required. Both properties are directly linked to chemical extractives and particularly to phenols. Based on a broad sample of trees (583) from European and Japanese larch and their interspecific hybrid, we investigated the variability in phenolic content, and particularly of two major compounds, Taxifolin (Tax) and Dihydrokaempferol (DHK), and their link with wood colour. At the individual wood sample level, phenolic contents ranged from 6.0 to 55.9 mg eq. Tax/g DW. Taxifolin was the most abundant constituent (range: 1.3–41.7 mg/g DW) compared with DHK (0.5–13.7 mg eq. Tax/g DW). A high variability among taxa, genotypes and individual trees within taxa and within trees was observed. Japanese larch had the highest amount of total phenols and of Taxifolin and European larch the lowest. For DHK, Japanese larch was the poorest compared with European larch. Hybrid larch had both a high content of Taxifolin and of DHK. Variability for colour parameters was on average weaker than for phenolic content but still large enough to show significant differences between taxa. Correlations between colour parameters and extractives were moderate to weak. At the mean genotype level, a good link (r > 0.51, p < 0.001) was found between a* (red–green axis in CIELAB) and total phenols and Taxifolin contents and between L* (Lightness) and DHK content (r > 0.54). The broad variability observed in this study at different levels for phenolics offers opportunities for breeders to genetically improve the quality of larch heartwood, in particular in relation to decay resistance.  相似文献   
967.
Atlantic heaths are semi-natural habitats of high biodiversity interest which once covered large areas of the Atlantic Region. Nowadays these heathlands are dramatically reduced in many countries although they still cover wide areas in the north-west Iberian Peninsula, especially in the poorest and most socially marginal areas that are frequently affected by wildfires. We review the role of livestock grazing as a sustainable management strategy for heathlands in Europe. We have worked on a generalized conceptual framework for the management of a resource of nutritional and environmental value by drawing together evidence from studies of the livestock and the community ecology of grazed plants and the associated fauna. Key factors that influence grazing impact, such as type of livestock (animal species and breed) and their management are discussed. Goats thrive better than sheep, and horses than cattle, when heathland vegetation is the predominant resource available. Regardless of the type of livestock species managed, the low nutritive value of this vegetation hinders the maintenance of productive groups of suckler dams with offspring through the grazing season. The nutritional requirements of livestock can be met by adding improved pasture areas to heathlands. Under that strategy, sheep have the best productive performance and cattle the poorest. Management of mixed flocks with goats can lead to a more efficient use of vegetation, improve productivity and develop a patchier habitat which supports a richer associated fauna. Overall the results indicate that the sustainability of livestock grazing in these marginal lands will be achieved if they are managed effectively according to the available vegetation and their effects on the biodiversity.  相似文献   
968.
The effect of two bacterial strains to enhance bioactive contents (total phenolic compounds, total flavonoid compounds and isoflavones) and antioxidant activity on 3-day-old soybean sprouts were investigated. To identify bacterial determinants responsible for these effects, viable and UV-treated strains were delivered to wounded seeds at different concentration. Multivariate analysis performed with all the evaluated parameters indicated the different effectiveness of Stenotrophomonas maltophilia N5.18 and Pseudomonas fluorescens N21.4 based on different structural and metabolic determinants for each. N21.4 increased total phenolics and isoflavones from the genistein family, while N5.18 triggered biosynthesis of daidzein and genistein families coupled to a decrease in total phenolics, suggesting different molecular targets in the phenilpropanoid pathway. Only extracts from N5.18 treated seeds showed an improved antioxidant activity according to the β-carotene bleaching prevention method. In summary, bioeffectors from both bacterial strains are effective tools to improve soybean sprouts quality; structural elicitors from N5.18 also enhanced antioxidant activity, being the best alternative for further development of a biotechnological procedure.  相似文献   
969.
The conceptual ability to source, combine, and store substances that enhance technology or social practices represents a benchmark in the evolution of complex human cognition. Excavations in 2008 at Blombos Cave, South Africa, revealed a processing workshop where a liquefied ochre-rich mixture was produced and stored in two Haliotis midae (abalone) shells 100,000 years ago. Ochre, bone, charcoal, grindstones, and hammerstones form a composite part of this production toolkit. The application of the mixture is unknown, but possibilities include decoration and skin protection.  相似文献   
970.

The search for ecological technologies that favour germination processes in agricultural and forestry seeds is a topic of interest as an environmentally friendly option. This study was a systematic review and meta-analysis to examine whether magnetic field direct exposure of seeds has a specific effect on germination. Using Scopus (2000–2020) and Web of Science (2000–2020) databases, a bibliographic search was carried out using the following expressions (pre-sowing AND seed AND magnetic) to filter the references in the title, abstract and keywords of the articles published. The calculation and declaration of the effect size was performed by comparing binary results through applying the Odds-Ratio register with a 95% confidence interval (CI). The random effects model was applied with the DerSimonian and Laird method. A total of 175 articles were found, of which only 26 were accepted for systematic review and meta-analysis. Three subgroups were established according to the magnetic field strengths. The subgroup corresponding to intensities between 1 and 50 mT presented an Odds-Ratio of 0.49 with a CI of (0.19, 0.79), Q (14)?=?24.77, p?=?0.04, indicating that the treatment had a significant effect. The remaining subgroups showed no significant effect. Likewise, the global meta-analysis revealed a significant effect in favour of the treatment, with an Odds-Ratio of 0.68, a CI of (0.41, 0.94), Q (28)?=?44.03, p?=?0.03. From the studies included in the meta-analysis, the results show a significant effect of seed direct exposure to magnetic fields that can be used to increase seed germination.

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