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111.
Surveillance of hepatitis E virus (HEV) in risk groups is an important strategy to monitor its circulation pattern and to timely detect changes thereof. The aims of this cross-sectional study were to estimate the prevalence of HEV infections in pigs and humans from different regions of the country, to identify risk factors for increasing anti-HEV IgG prevalence and to characterize HEV strains. The presence of anti-HEV antibodies was assessed by commercial ELISA in serum samples from the general population, farm and slaughterhouse employees, as well as pigs sampled in the three regions of Cuba from February to September 2016. Overall, individuals with occupational exposure to swine or swine products (70/248, 28.2%) were 4 times more likely to be seropositive compared to the general population (25/285, 8.7%; OR: 4.18; p < .001). Within the risk group, risk factors included age, number of years working in a professional activity with direct exposure to swine, geographic region and distance between residence and closest professional swine setting, while wearing gloves had a protective effect. Prevalence of total anti-HEV antibodies in swine was 88.2% (165/187) and HEV RNA was detected by real-time RT-PCR in 9.2% (16/173) swine stools. All HEV strains sequenced clustered within genotype 3. Some strains clearly belonged to subtype 3a, while another group of strains was related with subtypes 3b and 3 k but partial HEV sequences did not allow unequivocal subtype assignment. These findings suggest that the high HEV exposure in Cuban individuals with swine-related occupations could be due to enzootic HEV in certain regions, direct contact with infectious animals or their products as well as environmental contamination.  相似文献   
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The kingdom of Urartu existed in Eastern Anatolia from about 850 B.C. to 600 B.C. Historical references and archaeological evidence indicate the considerable artistic and technical skill of the Urartian people. The supply of the kingdoms capital Tupa/Rusahinili with drinking and irrigation water is an outstanding example of a well-planned and excellently built historical inter-basin water management project. The system has been in operation for more than 2000 years and still serves, at least partly, its original purpose.  相似文献   
115.
Vegetative compatibility (vc) and mating types and genetic diversity of Cryphonectria parasitica isolates were determined using 183 isolates obtained from 215 infected chestnut trees growing in 13 provinces of Turkey. Based on the cultural aspects, 143 of these isolates were evaluated as virulent whereas the remaining 40 isolates were hypovirulent. When vc types of 183 isolates were classically differentiated, 135 of them matched to EU-1 (82.3%), 29 of them to EU-12 (17.6%) vc type, whereas 19 of them did not match to the two. When molecular vic markers were used, all the isolates were assigned to two EU vc types; 149 to EU-1 (81.4%) and 34 (18.5%) to EU-12. Of the majority of the isolates, 134 (73.2%) had mating-type MAT-1, while 44 (24%) isolates had MAT-2 and 5 (2.8%) isolates had both mating types. The population analysis based on two DNA marker systems, Inter-Primer Binding Site and Start Codon Targeted Polymorphism, showed no intraspecific genetic variation among the C. parasitica isolates. The prevalence of two dominant vc types revealed by this study shows that biological control with hypovirulent EU-1 and EU-12 isolates will be significant for the country. The results might be helpful to chestnut breeders carrying out resistance breeding studies to manage this disease based on hypovirulence attributed to Cryphonectria hypovirus 1.  相似文献   
116.
Arıkan  Bülent  Mohr  Franziska  Bürgi  Matthias 《Landscape Ecology》2021,36(8):2295-2315
Landscape Ecology - Landscape archaeology has a lot to offer to landscape ecology, being an interdisciplinary approach that emphasizes the study of long-term human–environment dynamics. We...  相似文献   
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Landscape Ecology - Landscape ecology early on developed the awareness that central objects of investigation are not stable over time and therefore the historical dimension must be included, or at...  相似文献   
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The fate of fenpropimorph and its metabolite fenpropimorphic acid was investigated in a silty sand soil and in a clayey silt soil. In laboratory and field experiments fenpropimorph disappeared without a lag phase. A few days after application fenpropimorphic acid was detected. Additional laboratory experiments with [14C]fenpropimorph emphasized the significance of mineralization and the formation of non-extractable residues. The determination of soil/water distribution coefficients of parent compound and metabolite yielded a higher leaching potential for fenpropimorphic acid due to its higher polarity. This was confirmed by performing a laboratory column test under worst-case conditions. Under field conditions, however, fenpropimorphic acid was detected only in the superficial soil layers (0–5 cm) of both investigation sites at very low concentrations.  相似文献   
119.
Context

Landscape and local habitat traits moderate wild bee communities. However, whether landscape effects differ between local habitat types is largely unknown.

Objectives

We explored the way that wild bee communities in three distinct habitats are shaped by landscape composition and the availability of flowering plants by evaluating divergences in response patterns between habitats.

Methods

In a large-scale monitoring project across 20 research areas, wild bee data were collected on three habitats: near-natural grassland, established flower plantings and residual habitats (e.g. field margins). Additionally, landscape composition was mapped around the research areas.

Results

Our monitoring produced a dataset of 27,650 bees belonging to 324 species. Bee communities on all three habitats reacted similarly to local flower availability. Intensively managed grassland in the surrounding landscape had an overall negative effect on the studied habitats. Other landscape variables produced diverging response patterns that were particularly pronounced during early and late season. Bee communities in near-natural grassland showed a strong positive response to ruderal areas. Flower plantings and residual habitats such as field margins showed a pronounced positive response to extensively managed grassland and woodland edges. Response patterns regarding bee abundance were consistent with those found for species richness.

Conclusion

We advise the consideration of local habitat type and seasonality when assessing the effect of landscape context on bee communities. A reduction in the intensity of grassland management enhances bee diversity in a broad range of habitats. Moreover, wild bee communities are promoted by habitat types such as ruderal areas or woodland edges.

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120.
The purpose of this study was to examine the genotypic variation in maize doubled haploid (DH) lines response to brassinosteroid and gibberellin inhibitors. Plant responses to hormone inhibitors were determined in growth chamber experiments using germination paper for three different seedling treatments: application of propiconazole (Pcz), uniconazole (Ucz) or water (control). Mesocotyl length (ML) was more sensitive to hormone inhibitors, especially to the Ucz treatment, than other seedling traits. ML was significantly correlated with other traits in the Ucz treatment. All the seedling traits showed moderate-to-high broad sense heritability values, ranging from 0.39 to 0.82. The Euclidian genetic distances of inbred line pairs ranged from 1.27 to 19.94, indicating there was a high level of variability across the maize DH lines used in this study. DH lines with extreme MLs were identified, which can provide valuable breeding resources for improving abiotic stress tolerance, and for further genetic studies.  相似文献   
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