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91.
The monitoring of an experimental feeding station established in northern Spain allowed the evaluation of how this type of resource, predictable in space but not in time, was exploited by a guild of avian scavengers in relation to factors such as season, hour of disposal and presence of the dominant species. The presence of Egyptian Vultures Neophron percnopterus at carcasses was more likely during spring, and richness and diversity of avian scavengers was lower during the summer and when Griffon Vultures Gyps fulvus arrived earlier. The temporal unpredictability of the resource may favour exploitation by smaller and less competitive scavengers. New European regulations may present an opportunity to develop effective conservation measures to support functional scavenger assemblages. 相似文献
92.
93.
H. Thomas J. Sauerborn D. Muller-Stover J. Kroschel 《Biocontrol Science and Technology》1999,9(3):379-381
A survey of pathogens of the root-parasitic weed Orobanche aegyptiaca Pers. was carried out in Nepal. More than 70% of the fungal strains isolated from infected plants belonged to the genus Fusarium. Other fungi isolated were Acremonium fusidioides, Alternaria alternata, Cladosporium cladosporioides, Epicoccum nigrum, Mortierella alpina, Papulaspora sp., Phoma spp., Sordaria fimicola , Rhizoctonia sp., Trichoderma spp. and Trichothecium roseum. 相似文献
94.
Yasseen Mohamed-Yasseen Suzanne Helene Costanza 《In vitro cellular & developmental biology. Plant》1996,32(2):100-102
Summary Two protocols for clonal propagation of kurrat (Allium ampeloprasum var.kurrat) using explants from the basal plates of mature plants are described. In direct formation, explants were cultured in Murashige
and Skoog (MS) medium and supplemented with either benzyladenine at 0.0 or 4.4 μM, or supplemented with 7.0 μM benzyladenine and 0.1 μM naphthaleneacetic acid. Shoots appeared after 4 wk of culture. In the two-step procedure, explants were cultured first on
MS medium supplemented with 1.4 μM 2,4-dichlorophenoxyacetic acid and 1.4 μM kinetin, and incubated in the dark for 4 wk. They were then transferred to MS medium supplemented with 4.4 μM benzyladenine for shoot formation. All shoots were rooted on MS medium containing 5 g·liter−1 activated charcoal. Normal viable plants were successfully established in soil. 相似文献
95.
José A. Donázar Ainara Cortés-Avizanda Eneko Arrondo Alejandro Delgado-González Olga Ceballos 《Ibis》2023,165(1):305-311
Protected areas in southern Europe are important for the conservation of large avian scavengers. However, the effects an increasing number of visitors may have on the scavengers' patterns of movement are unknown. Here, we took advantage of data collected from seven GPS-tagged adult Griffon Vultures Gyps fulvus breeding in the Bardenas Reales Natural Park in northern Spain to determine whether foraging birds moved to more remote areas on the days when the number of visitors increased. We found that although the number of visitors did appear to affect movement patterns, this had a smaller effect size compared with the mean temperature of the day. Additionally, males moved further than females. If the number of visitors to natural areas continues to increase, local exclusions of Griffon Vultures may become more common, so further research is needed to address the potential consequences for the scavenger population and ecosystem functions and services they provide. 相似文献
96.
Screening of 1315 males from two Egyptian oases for glucose-6-phosphate dehydrogenase deficiency (G-6PD) found an incidence
of 5.9%. The rate of acetylation of sulfadimidin was also studied, and a bimodal distribution was found with 73% rapid acetylators.
There is a correlation between high frequency of G-6PD deficiency and high frequency of slow acetylation rate.
This work was supported by a grant from the International Center of Agricultural Research in the Dry Areas (ICARDA), Nile
Valley project of faba beans. 相似文献
97.
Mohamed S. Hassanane Amal A.M. Hassan Fatma M. Ahmed Esteftah M. El-Komy Khaled M. Roushdy Nagwa A. Hassan 《Journal of Genetic Engineering and Biotechnology》2018,16(1):83-88
Egyptian chickens, representing 2 breeds and 7 strains, were genotyped using the PCR-RFLP and sequencing techniques for detection of a non-synonymous dimorphism (G/A) in exon 14 of chicken Myxovirus resistance (Mx) gene. This dimorphic position is responsible for altering Mx protein’s antiviral activity. Polymerase Chain reactions were performed using Egyptian chickens DNA and specific primer set to amplify Mx DNA fragments of 299 or 301?bp, containing the dimorphic position. Amplicons were cut with restriction enzyme Hpy81. Genotype and allele frequencies for the resistant allele A and sensitive allele G were calculated in all the tested chickens. Results of PCR-RFLP were confirmed by sequencing. The three genotypes AA, AG, GG at the target nucleotide position in Mx gene were represented in all the studied Egyptian chicken breeds and strains except Baladi strain which showed only one genotype AA. The average allele frequency of the resistant A allele in the tested birds (0.67) was higher than the sensitive G allele average frequency in the same birds (0.33). Appling PCR-RFLP technique in the breeding program can be used to select chickens carrying the A allele with high frequencies. This will help in improving poultry breeding in Egypt by producing infectious disease-resistant chickens. 相似文献
98.
Basic ecological information is still lacking for many species of African vultures. The Hooded Vulture Necrosyrtes monachus is known as a rare breeding resident in north-eastern South Africa. This study set out to monitor the nests of Hooded Vultures and, secondarily, White-backed Vultures Gyps africanus in the Olifants River Private Nature Reserve over two breeding seasons in 2013 and 2014. A total of 12 Hooded Vulture nests, placed mostly in the tree Diospyros mespiliformis, were found along the Olifants River, with an average inter- nest distance of 0.76 km. Nest success was estimated to be between 0.44–0.89 offspring pair?1 y?1 in 2013 and 0.50–0.67 offspring pair?1 y?1 in 2014, which are the first estimates for Hooded Vultures in South Africa. It is thought that nests of this species have been under-reported due to the fact that they are placed within or below the canopy of densely leafed trees and hence difficult to view from aerial surveys. African White-backed Vultures also bred along the Olifants River, with nests placed in clusters of up to six. Nesting density of this species ranged from about 1.0 to 1.2 nests km?1 and nests were predominantly placed in Ficus sycomorus trees. 相似文献
99.
S O Keita 《American journal of physical anthropology》1992,87(3):245-254
An analysis of First Dynasty crania from Abydos was undertaken using multiple discriminant functions. The results demonstrate greater affinity with Upper Nile Valley patterns, but also suggest change from earlier craniometric trends. Gene flow and movement of northern officials to the important southern city may explain the findings. 相似文献
100.
S. O. Y. Keita 《International Journal of Anthropology》1995,10(2-3):107-123
A review of studies covering the biological relationship of the ancient Egyptians was undertaken. An overview of the data
from the studies suggests that the major biological affinities of early southern Egyptians lay with tropical Africans. The
range of indigenous tropical African phenotypes is great; and this range of variation must be considered in any discussion
of the Nile Valley peoples. The early southern Egyptians belonged primarily to an African descent group which gained some
Near Eastern affinity through gene flow with the passage of time. 相似文献