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71.
- Priority‐area selection is a core phase of systematic conservation planning, often carried out using a single (surrogate) taxon. Efficient surrogates are expected to yield taxonomically representative priority areas that embrace the populations not only of the surrogate but also the surrogated taxa. Compared with the terrestrial realm, surrogacy performance of riverine taxa has received much less attention.
- This study compared the surrogacy performance of fishes (FI), macrophytes (MP), and benthic macroinvertebrates (MI) in terms of total area, connectedness, spatial congruence, and taxonomic representativeness of priority areas in the Middle Danube basin (Hungary). Setting three target values for each surrogate group, nine area prioritization designs were run by using a purpose‐written connectivity‐centric algorithm to emphasize the importance of longitudinal connectivity.
- FI provided the smallest, MP the intermediate, and MI the largest priority areas or solutions. Connectedness was greatest for FI, being one order of magnitude higher than for the other two groups. Pairwise spatial congruence was highest between FI and MP, lowest between MP and MI, and intermediate for FI and MI. MI yielded the most representative solutions, although the number of occurrences of the surrogated taxa in the solution, as a criterion of representation, modified the ratio of the taxa represented. Areas compiled from the overlapping parts of the surrogate‐specific priority sets proved to be smaller than, and similarly representative of, single‐taxon solutions.
- Taxon‐rich groups such as MI can serve as efficient surrogates, but that can result in larger solutions than for less taxon‐rich surrogates. Apart from the size, the compactness of the solutions seems to be determined by the identity of the surrogate taxa, and FI can be alternative surrogates in connectivity‐centric prioritization. At the same time, multi‐group approaches can enhance the robustness of area prioritization in terms of representativeness compared with single‐taxon procedures.
72.
Gao-Yang Peng Tibor Kurtn Attila Mndi Jing He Zheng-Yu Cao Hua Tang Shui-Chun Mao Wen Zhang 《Marine drugs》2021,19(5)
Three new p-terphenyl derivatives, named 4″-O-methyl-prenylterphenyllin B (1) and phenylcandilide A and B (17 and 18), and three new indole-diterpene alkaloids, asperindoles E–G (22-24), were isolated together with eighteen known analogues from the fungi Aspergillus candidus associated with the South China Sea gorgonian Junceela fragillis. The structures and absolute configurations of the new compounds were elucidated on the basis of spectroscopic analysis, and DFT/NMR and TDDFT/ECD calculations. In a primary cultured cortical neuronal network, the compounds 6, 9, 14, 17, 18 and 24 modulated spontaneous Ca2+ oscillations and 4-aminopyridine hyperexcited neuronal activity. A preliminary structure–activity relationship was discussed. 相似文献
73.
The live attenuated bovine viral diarrhea virus components of a multi-valent vaccine confer protection against fetal infection 总被引:1,自引:0,他引:1
Kovács F Magyar T Rinehart C Elbers K Schlesinger K Ohnesorge WC 《Veterinary microbiology》2003,96(2):117-131
Fetal infection with bovine virus diarrhea virus (BVDV) causes severe economic loss and virus spread in cattle. This study investigated the ability of modified live BVDV I and II components of a commercially available modified live virus (MLV) vaccine (Breed-Back FP 10, Boehringer Ingelheim Vetmedica Inc.) to prevent fetal infection and abortion, and therefore the birth of persistently infected animals. Heifers immunized with vaccine 4-8 weeks before insemination showed no adverse effects. All vaccinated animals had seroconverted to BVDV 4 weeks after immunization. Pregnant heifers were divided into two vaccination and two control groups and challenged with type I or II BVDV on days 60-90 of gestation. Seroconversion, clinical signs, immunosuppression, viremia, mortality, abortion rate, and fetal infection were studied. Post-challenge, 6/11 (type I challenged) and 8/11 (type II challenged) vaccinated heifers were free from clinical signs of BVD. Post-challenge clinical signs noted in the vaccinated groups were mild to moderate, while all unvaccinated controls had clinical signs ranging from moderate to severe. Viremia was not detected post-challenge in any of the vaccinated heifers. However, 100% of the controls were BVDV viremic on at least 1 day post-challenge. One of 22 vaccinated heifers had transient leukopenia, whereas 2/8 and 6/7 unvaccinated heifers in control groups I and II, respectively, had transient leukopenia. Type II BVDV infection led to abortion or death in 86% of unvaccinated heifers. The corresponding vaccinated group showed no deaths or abortions. All control group fetuses were infected with BVDV. The test vaccine gave 91% (type I BVDV challenged) and 100% (type II BVDV challenged) protection from fetal infection. This vaccine is safe and effective against fetal infection, abortion (type II BVDV) and the birth of persistently infected animals. 相似文献
74.
75.
Letesson JJ Lestrate P Delrue RM Danese I Bellefontaine F Fretin D Taminiau B Tibor A Dricot A Deschamps C Haine V Leonard S Laurent T Mertens P Vandenhaute J De Bolle X 《Veterinary microbiology》2002,90(1-4):317-328
Although Brucella is responsible for one of the major worldwide zoonosis, our understanding of its pathogenesis remains in its infancy. In this paper, we summarize some of the research in progress in our laboratory that we think could contribute to a better understanding of the Brucella molecular virulence mechanisms and their regulation. 相似文献
76.
Csaba Tölgyesi Zoltán Bátori Róbert Gallé István Urák Tibor Hartel 《Strength and Conditioning Journal》2018,71(5):571-577
Rangelands with scattered trees are complex and dynamic systems with a long history in Europe. Generally referred to as “wood-pastures,” they are considered to have outstanding conservation value. Thorny shrubs are important for supporting the biodiversity of these wooded rangelands, as well as facilitating the regeneration of trees by acting as nurse species. We assess the direct effects of temporary shrub encroachment under the cover of mature sparse trees on overall plant and habitat diversity. We surveyed the herb layer of the main landscape features of a wood-pasture: open pasture, trees with a grass understory, trees with shrubs, and adjacent forest edges. The herb layer under trees with shrubs resembled that of forest edges more than open pastures and trees with grass. Trees with grass had a higher cover of ruderal species than trees with shrubs, while forest edges and open pastures had a lower cover of them. Forest species were absent from open pastures but were well represented in the other sites. The herb layer of trees with shrubs and forest edges had similar cover values, while trees with grass had a significantly lower cover of herbs than the other types. Trees with shrubs had higher species richness than any of the other three landscape features and had a much higher proportion of diagnostic species. We conclude that the scattered trees and shrubs of the studied silvopastoral system have additive facilitative effects on their understory, probably through modifying the microenvironment and grazing pressure, leading to the formation of temporary diversity hot spots with distinct vegetation. Thus maintaining a moderate level of shrub-encroachment under sparse trees is recommended for not only creating safe havens for tree recruitment but also increasing the overall species and habitat diversity of wood-pastures. 相似文献
77.
Tibor Hartel Nora Fagerholm Mario Torralba Ágnes Balázsi Tobias Plieninger 《Strength and Conditioning Journal》2018,71(5):536-544
Rangelands in Europe are imprinted by livestock production and embedded in mosaic landscapes of grasslands, croplands, woodlands, and settlements. They developed as social-ecological systems: People managed rangelands in order to maintain or enhance their ecosystem services, which in turn supported their well-being. The appreciation of ecosystem services provided by rangelands depends on the broad, socioeconomic aspirations and abilities of the managers and the capital available to achieve these aspirations. Here we propose four archetypical social-ecological system representations for European rangelands along the dimensions of socioeconomic aspirations (i.e., oriented toward conventional or sustainable production) and available financial capital (i.e., low or high) to employ farming technologies on rangelands. The four archetypes are aspiration misfit, pockets of sustainability, techno-dependence, and money dependent sustainability. We describe the landscape physiognomy, ecosystem service appreciation, and management-related synergies and trade-offs in ecosystem services supply related to each archetype and formulate a number of research questions to document and further understand them as social-ecological systems. We include the importance of urbanization, land grabbing, and institutional networks in shaping the social-ecological archetypes of rangelands and the relationship between our social-ecological archetypes and the resilience and transformability of rangelands. 相似文献
78.
79.
Bla Darvas Huw H. Rees Nigel Hoggard Mahmoud H. Tag El-Din Eiichi Kuwano Ivn Blai Tibor Timr 《Pest management science》1992,36(2):135-142
The cytochrome P-450-dependent microsomal and mitochondrial ecdysone 20-monooxygenase systems convert ecdysone into 20-hydroxyecdysone. The microsomal fraction of fat bodies of zero h wandering stage fleshfly larvae (Neobellieria bullata; Diptera: Sarcophagidae) has a high ecdysone 20- monooxygenase activity. The effects of cytochrome P-450 inhibitors were investigated in vitro on microsomal ecdysone 20-monooxygenase. Metyrapone, fenarimol and certain imidazole derivatives (KK-42, KK-110, KK-135 and PIM) are strong inhibitors. The IC50 value of KK-110, which is the strongest inhibitor, is 2 × 10?7 M. A triazolyl and two cyclopropylamine derivatives have low activity. The activities of different NADPH-cytochrome c (P-450) reductase inhibitors were also assessed; diquat dibromide is a moderate inhibitor of microsomal ecdysone 20-monooxygenase, while paraquat dichloride has no activity. In-vivo experiments with cytochrome P-450 inducers and inhibitors gave the following results: (a) fenarimol, FI-121, precocene-2 caused “permanent” first-instar larvae; (b) barbital, phenobarbital and their sodium salts caused significant delay in larval development; (c) PIM, PTM, metyrapone, KK-42, KK-135, J-2710, RH 5849 and colchicine caused moulting disturbances; (d) J-2710, PIM, PTM, KK-42, KK-135, RH 5849 and colchicine caused lethal spiracle and mandible malformation; (e) KK-110, fenarimol, barbital and phenobarbital caused precocious pupariation. 相似文献
80.
Sipos Péter Tóth Adrienn Kis Viktória Kovács Balázs Réka Kovács Ivett Németh Tibor 《Journal of Soils and Sediments》2019,19(4):1775-1787
Journal of Soils and Sediments - Heterogeneity of soil mineral particles may lead to the misinterpretation of bulk sorption data on their role in metal sorption, which may be resolved through the... 相似文献