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61.
Phenylalanine ammonia-lyase activity (PAL, EC 4.3.1.5), total phenolics, soluble proteins, malondialdehyde and metals accumulation in four-week old chamomile (Matricaria chamomilla) plants cultivated in nutrient solution and exposed to low (3 μM) and high (60 and 120 μM) levels of cadmium (Cd) or copper (Cu) for 7 days were studied. High Cd concentrations had a stimulatory effect on PAL activity and soluble phenolics accumulation while high Cu doses decreased soluble proteins in the leaf rosettes. In the roots, extreme stimulatory effects of 60 and 120 μM Cu were observed on PAL activity, phenolics and malondialdehyde accumulation, while protein content was reduced by these Cu doses. Cd accumulation was higher in the leaf rosettes compared to copper, but the opposite was recorded in the roots. Taken together, the stimulatory effect of Cu on phenolic metabolism was recorded, even though high malondialdehyde accumulation may be an indication that phenolics was not sufficient to counteract reactive oxygen species formation thus leading to damage of membrane integrity. In comparison to Cd, Cu had more noticeable effect on the parameters studied to support its strong redox-active properties. These facts in correlation to antioxidative properties of phenolic metabolites are also discussed. 相似文献
62.
Jozef M. Pacyna 《Water, air, and soil pollution》1986,30(3-4):825-835
Measured air concentrations of several trace elements in southern Scandinavia have been related to long range transport and emissions of the same elements from sources in Europe using receptor modelling and statistical trajectory sector analysis. A good agreement, within a factor of 1.5 between estimates and measurements, has been obtained for Mn, Ni, Cu, and As. Significant differences were noted for V and Pb. 相似文献
63.
Tree species selection for land rehabilitation in Ethiopia: from fragmented knowledge to an integrated multi-criteria decision approach 总被引:1,自引:1,他引:0
Bert Reubens Clara Moeremans Jean Poesen Jan Nyssen Sarah Tewoldeberhan Steve Franzel Jozef Deckers Caleb Orwa Bart Muys 《Agroforestry Systems》2011,82(3):303-330
Dryland regions worldwide are increasingly suffering from losses of soil and biodiversity as a consequence of land degradation.
Integrated conservation, rehabilitation and community-based management of natural resources are therefore of vital importance.
Local planting efforts should focus on species performing a wide range of functions. Too often however, unsuitable tree species
are planted when both ecological suitability for the targeted area or preferences of local stakeholders are not properly taken
into account during selection. To develop a decision support tool for multi-purpose species selection, first information needs
to be pooled on species-specific ranges, characteristics and functions for a set of potentially valuable species. In this
study such database has been developed for the highly degraded northern Ethiopian highlands, using a unique combination of
information sources, and with particular attention for local ecological knowledge and preferences. A set of candidate tree
species and potentially relevant criteria, a flexible input database with species performance scores upon these criteria,
and a ready-to-use multi-criteria decision support tool are presented. Two examples of species selection under different scenarios
have been worked out in detail, with highest scores obtained for Cordia africana and Dodonaea angustifolia, as well as Eucalyptus spp., Acacia abyssinica, Acacia saligna, Olea europaea and Faidherbia albida. Sensitivity to criteria weights, and reliability and lack of knowledge on particular species attributes remain constraints
towards applicability, particularly when many species are jointly evaluated. Nonetheless, the amount and diversity of the
knowledge pooled in the presented database is high, covering 91 species and 45 attributes. 相似文献
64.
Findoráková Lenka Šestinová Oľga Matik Marek Hančuľák Jozef Bureš Radovan 《Journal of Soils and Sediments》2022,22(9):2448-2458
Journal of Soils and Sediments - To evaluate the ecological risk, physico-chemical properties, and the impact of anthropogenic sources on permanent eighteen samples of grass vegetation soils (PGVS)... 相似文献
65.
66.
Huber S Roosje PJ Janda J Schnyder M Jungi TW Bertoni G Zurbriggen A Burgener IA 《Veterinary immunology and immunopathology》2011,144(3-4):247-254
Toll-like receptors recognize pathogen-associated molecular patterns of microbial origin, and ligand recognition results in the production of different immune mediators such as pro-inflammatory cytokines, interferon, reactive oxygen and nitrogen intermediates, and upregulation of costimmulatory molecules. As these receptors have a critical role in linking pathogen recognition to induction of inflammation and innate as well as adaptive immunity, there is tremendous interest in understanding how the tissue and cell-type expression of TLRs is regulated and its influence on the local innate immune response. While TLRs are well studied in humans and rodents, to date little is known about them in dogs. The purpose of this study was to develop canine specific antibodies against TLR2, 4, 5 and 9 that were used to measure relative expression of these TLRs in healthy and reactive canine mesenteric lymph nodes. All 8 rabbit sera (2 each for TLR2, 4, 5 and 9) were strongly positive in ELISA against the respective 2 peptides per TLR used for immunization. The purified antibodies selected specifically detected a protein band with an apparent size of approximately 70 kDa in lysates of canine PBMCs by Western blotting. Immunostaining was observed with purified antibodies against TLR4, 5 and 9, whereas for canine TLR2, staining was only observed with the unpurified antibodies. In the mesenteric lymph node of healthy dogs, the overall staining pattern was very similar for TLR4 and 5 with positive cells predominantly found in the internodular areas and lower part of the cortex. Compared to the TLR4 and 5, more cells stained positive for TLR9 especially in the lymphoid nodules. The reactive lymph nodes contained more TLR4 and 9 positive cells. Moreover, a shift of TLR-9 positive cells from the lymphoid follicles to the deep cortex and medullary cords was observed. Whereas TLR9 co-localized with CD79-positive areas, TLR4 and 5 antibodies stained cells primarily in the CD3-positive areas. All three TLR antibodies stained cells within the area that co-localized with lysozyme-positive cells. In conclusion, this study demonstrates that the antibodies generated against canine TLR 4, 5 and 9 identify the expression of these TLRs in formalin-fixed canine lymph nodes and demonstrate increased expression in reactive canine mesenteric lymph nodes. 相似文献
67.
Lutishoor Salisbury Jozef Laincz Jeremy J. Smith 《Journal Of Agricultural & Food Information》2013,14(3):250-266
This study compares undergraduate and graduate students’ preferences for information sources. It found that the largest percentage of undergraduates ranked Google Scholar, a scholarly database, as their 1st or 2nd choice for an information source, followed by Google, library scholarly databases, the library catalog, and library staff. The largest percentage of graduate students ranked library scholarly databases as their 1st or 2nd preference, followed by Google Scholar, the library catalog, Google, and library staff. There seems to be a connection between attendance in a library instruction session and the choice of library scholarly online databases. 相似文献
68.
Antagonism of local isolates of Trichoderna spp. on citrus root rot disease by Fusarium solani in the mekong delta of vietnam 下载免费PDF全文
Duong Minh Jozef Coosemans Le Lam Cuong Ester Vandersmissen Pham Van Kim 《浙江大学学报(农业与生命科学版)》2004,30(4):392-392
The local isolates of Trichoderrma spp. and Fusariun solani were colected from citrus orchards in the Mekong delta of Vietnam and isolated on PDA, PDB and TSM medium for antagonism and Koch's postulate testing. The results showed that the high chitinolytic enzymes content of Trichoderma isolates can antagonise with Fusarium solani isolates by preventing the germination of Fusarium macroconidia in in-vitro condition. There are five promising isolates of Trichoderna spp. having high antagonism with Fusarium solani. These Trichoderma isolates also grew well in rice straws, maize stems, weeds and water hyacinth biowaste materials. These results supply the promising trend for biological control of root rot disease on citrus orchards of the Mekong delta. 相似文献
69.
Tegebu FN Mathijs E Deckers J Haile M Nyssen J Tollens E 《Tropical animal health and production》2012,44(1):133-144
Livestock fulfill different functions. Depending on their livelihood strategies, households differ in their choice of what
type of animal to keep and on accumulation of the chosen animal overtime. Using a panel data of 385 rural households in a
mixed farming system in northern Ethiopia, this paper investigates the dynamic behavior of rural households’ livestock holding
to identify determinants of choice and accumulation of livestock overtime. Choice is analyzed for a principal animal, the
animal that constituted the largest value of livestock assets a household possessed, using a multinomial logit model. Results
indicate that rural households differ in their choice of what type of animal to keep. Agro-climatic conditions, sex and age
of household head, presence of an adult male member in a household, and liquidity are the major factors that influence the
type of principal animal households keep. Conditional on the principal animal selected, we analyzed the factors that determine
the accumulation of the chosen animals by correcting for selection bias. Area of land cultivated is the most significant factor
that explains the number of animals households keep. Other factors include sex of household head, diversification into nonfarm
self-employment, and shocks. 相似文献
70.
Vlaminck J Nejsum P Vangroenweghe F Thamsborg SM Vercruysse J Geldhof P 《Veterinary parasitology》2012,189(2-4):267-273
The significant economical consequences of infections with Ascaris suum in pigs are already well documented. However, due to the subclinical nature of the disease and the lack of practical diagnostic means, ascariasis often remains undiagnosed. Here we describe the development and evaluation of a novel indirect ELISA using the purified A. suum haemoglobin (AsHb) molecule as an antigen. Initial validation using sera from 190 pigs experimentally infected twice a week with A. suum and Trichuris suis (25 and 5eggskg(-1)day(-1) respectively) demonstrated that the AsHb ELISA is able to detect long-term exposure to A. suum with a high sensitivity and specificity (99.5% and 100.0% respectively). Furthermore, this serological technique proved to be more sensitive than faecal examination on week 7 and 14 of the experiment (99.5% and 100% compared to 59.5% and 68.4% respectively). Cross-reactivity caused by T. suis infection was shown to be limited after analysing sera from pigs with an experimental T. suis mono-infection. Seroconversion was shown to occur from week 6 onwards in pigs receiving 100 A. suum eggs 5 times a week. Preliminary testing of the ELISA on six randomly selected farms confirmed the results obtained in the artificial infection trials, showing a higher sensitivity of the serologic method compared to faecal examination. Finally, the ELISA was used to investigate Ascaris infection rates on 101 conventional Flemish pig farms. The results showed that on 38.6% of the farms less than 20% of the tested samples were seropositive, while in 19.8% of the farms 80-100% of all pigs were seropositive. The results of this study suggest that the AsHb ELISA could provide pig farmers and veterinarians with an easier and more sensitive way to estimate the overall prevalence of A. suum on their farm. 相似文献