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271.
A unique, record-breaking, killer heat wave occurred across several European countries during the first two weeks of August 2003. As weather conditions which characterize heat waves are highly conductive to tropospheric ozone formation and persistence, this is a contributing factor which should be regarded as a major stressor for biota. Hourly ozone means were captured between 1 and 15 August 2003 with automatic analysers in nine stations in Tuscany, distributed into six Districts. Compared to historical ozone reference climatology, daily maxima of 2003 were systematically higher by a factor of about 1.5, with differences which approached three times standard deviation. At the end of the period, cumulated ozone exposure over the threshold of 40 ppb (AOT40) was 4,750 ppb h in 2003, vs 2,200 ppb h of the historical series; such a difference was four times the standard deviation of the long-term series. Biological data are also enclosed in the present study, in the form of analysis of the ratio between above ground biomass produced by NC-S and NC-R clones of white clover when exposed to ambient air. Standardised samplings were performed on a monthly basis, and a significant difference between the two data sets was observed between summer 2003 and the historical series. The close correlation of high-ozone episode with increased temperature (as a consequence of increased solar radiation) suggests that, if climate change were to result in warmer summers in Europe, more frequent exceedances of dangerous ozone thresholds would be expected at the current emission levels.  相似文献   
272.
ABSTRACT

Agro-industrial activities such as livestock production and maize processing generate large amounts of waste that can pollute the environment if not treated. To reduce the environmental impact of such wastes, the use of nejayote and ovine manure as fertilizers in maize production was evaluated in terms of yield (GY), energy efficiency (EE) and benefit-to-cost ratio (BCR), during 2015 and 2016. A factorial experiment was designed combining nejayote (0, 75 and 150 m3 ha?1) with manure (0, 25 and 50 Mg ha?1), those treatments were compared with a chemical fertilizer treatment (120N–60P–30K); treatments were done in three replicates. Nejayote-manure fertilizers were characterized physical and chemically. Inputs and outputs used/obtained during the production cycle were registered in terms of their energy equivalents and economic value. At the end of each cycle GY, EE and BCR were calculated. Results showed that nejayote-manure mixtures were 19% more energy efficient and produced a yield 12% greater than chemical fertilization (P = 0.001), thus generating a BCR of 6.3 (P = 0.023). Organic fertilizers were useful as waste treatments and produced greater benefits than chemical fertilizers. Additionally, the water recovered from nejayote was enough to provide a 7.5 or 15 mm of gross irrigation during the crop cycle.  相似文献   
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Reintroduction projects represent viable options for animal conservation. They allow the establishment of new local populations and may contribute to recreating functional networks within a metapopulation. In the latter case, landscape connectivity may be a major determinant of the phase of spread of the reintroduced populations. Here, we deal with an example of a red deer (Cervus elaphus) translocation planned to enable the connection among existing isolated populations of the species in the Italian Alps. Our aim was to assess whether the analysis of landscape suitability and the simulation of dispersal of released individuals could shed light on the actual process of population spread. For these purposes, we adopted a modelling approach using radiotracking data to develop a habitat suitability map. On the basis of this map, we simulated the dispersal of the animals after release and we then compared the simulation results with the outcome of null models and with the observed population redistribution. The results suggest that the spread of the subpopulation was easier north-westward than southward. Taking into account landscape suitability, our simulations produced a reliable estimate of the ease of colonization of the valleys neighbouring the release-site and they allowed the identification and validation of a potential pathway for animal dispersal. The suitability model based on the monitoring of individuals in the earliest phase of establishment shed light on the spread of the population and on its potential connections with other deer subpopulations.  相似文献   
275.
Fungi of the Cryphonectriaceae family are globally known to be tree pathogens. In Brazil, several species of Chrysoporthe have been found causing stem and branch cankers in Pleroma (= Tibouchina) spp. Recently, Chrysoporthe puriensis was described as a new species causing stem and branch cankers in Pleroma granulosum, Pleroma candolleanum, and Pleroma heteromallum, all native species of the Melastomataceae family. During an investigation to collect isolates of the Cryphonectriaceae family in an important Brazilian biome, the Atlantic Forest, in Serra do Mar, structures typical of Chrysoporthe species were found in a different host, Pleroma mutabile. Fruiting bodies present in the bark of these trees were collected and isolated. The isolates were submitted on morphological characterization and phylogenetic analyses of the internal transcribed spacer (ITS) and β-tubulin gene regions using Maximum likelihood, Bayesian inference and Maximum parsimony methods. The isolates collected, for this study, were identified as C. puriensis. Pathogenicity tests on seedlings of Pleroma species and Eucalyptus clones revealed C. puriensis can infect and cause canker in these plant species as mortality. The results demonstrate the importance of delimiting the C. puriensis collection range to track its dissemination in other hosts. No host specificity was observed in the inoculation tests, suggesting this is an important finding, the pathogen causes diseases and mortality in several plants of the Atlantic Forest. Additionally, the pathogen can affect others hosts, such as Eucalyptus clones in commercial plantations.  相似文献   
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In a diabetic pregnancy, an altered maternal metabolism led to increased formation of reactive α‐dicarbonyls such as glyoxal (GO) and methylglyoxal (MGO) in the reproductive organs and embryos. The enzyme glyoxalase (GLO) 1 detoxifies reactive α‐dicarbonyls thus protecting cells against malfunction or modifications of proteins by advanced glycated end products (AGEs). The aim of this study was to analyse the influence of a maternal insulin‐dependent diabetes mellitus (IDD) on GLO1 expression and activity in preimplantation embryos in vivo and human trophoblast cells (Ac‐1M88) in vitro. Maternal diabetes was induced in female rabbits by alloxan before conception and maintained during the preimplantation period. GLO1 expression and activity were investigated in 6‐day‐old blastocysts from healthy and diabetic rabbits. Furthermore, blastocysts and human trophoblast cells were exposed in vitro to hyperglycaemia, GO and MGO and analysed for GLO1 expression and activity. During gastrulation, GLO1 was expressed in all compartments of the rabbit blastocyst. Maternal diabetes decreased embryonic GLO1 protein amount by approx. 30 per cent whereas the enzymatic activity remained unchanged, indicating that the specific GLO1 activity increases along with metabolic changes. In in vitro cultured embryos, neither hyperglycaemia nor MGO and GO had an effect on GLO1 protein amount. In human trophoblast cells, a stimulating effect on the GLO1 expression was shown in the highest GO concentration, only. Our data show that maternal diabetes mellitus affects the specific activity of GLO1, indicating that GLO1 was post‐translationally modified due to changes in metabolic processes in the preimplantation embryos.  相似文献   
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279.
Journal of Plant Diseases and Protection - Limited information is available on the distribution of grapevine red blotch virus (GRBV) in grape-growing regions outside North America. In this study,...  相似文献   
280.

Background

A study was carried out to evaluate the response of different native sheep breeds to experimental infection with Anaplasma ovis, the most prevalent sheep tick-borne pathogen in Apulia (Southern Italy). Thirty-four lambs belonging to a Northern European breed (Suffolk) and two Southern Italian breeds (Comisana and Altamurana) were infected. Eleven clinical as well as haematological parameters were monitored at different temporal resolutions on the same subjects before and after the infection, resulting in a data set of 435 observations. The present work, aiming to further the research, presents the results of a multivariate analysis carried out to identify which parameters out of the eleven considered are the most reliable parameters to be considered as markers of the disease phenotype as well as prognosticators of practical clinical importance.

Results

Data were analysed by discriminant analysis. Out of the eleven considered variables (red blood cells, packed cell volume, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin content, haemoglobin concentration, white blood cells, neutrophils, leukocytes, platelets, rectal temperature), only seven were included in the step-wise model since significantly increasing the Mahlanobis distance between the two closest groups. Both discriminant functions resulted to be highly significant (P < 0.0001) and the percentage of variation accounted for by the first discriminant function was 63.6% of the variance in the grouping variable.

Conclusions

Taken together, the observed results stress the marked differentiation among the three breeds in terms of physio-pathological phenotypes indicating packed cell volume and red blood cell count as the most informative parameters in the routine clinical practice for A. ovis infection in sheep.  相似文献   
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