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排序方式: 共有137条查询结果,搜索用时 109 毫秒
21.
Povolo M Pelizzola V Lombardi G Tava A Contarini G 《Journal of agricultural and food chemistry》2012,60(1):299-308
The determination of the geographical origin of dairy products is an ongoing issue. In this paper the effects of botanical diversity of two pastures on the hydrocarbon and fatty acid composition of cheese fat were studied, over 2 years of experimentation. Two areas in the Italian southwestern Alpine region, dominated by Trifolium alpinum (T) and Festuca nigrescens (F) vegetation, respectively, were chosen, and milk obtained from cows grazing on these pastures was used to produce a semihard traditional cheese. Cheese samples showed a significantly different composition of most linear hydrocarbons, odd-chain (C15, C17, and C17:1) and unsaturated (trans-11,cis-15-C18:2, C18:3, C20:4n-6, C20:4n-3, and 20:5n-3) fatty acids, according to pasture type. The ratio between C(29) and C(27) linear hydrocarbons, unlike the absolute content of the single molecules, showed a good discriminating ability between the two pastures and was little affected by the natural variability due to the climatic and environmental factors. 相似文献
22.
Giovenale Moirano Lorenzo Richiardi Mattia Calzolari Franco Merletti Milena Maule 《Zoonoses and public health》2020,67(1):54-61
In Italy, the first human case of West Nile Virus (WNV) infection was reported in 2008 and, since then, the number of cases has been steadily increasing. In this study, we describe the temporal and spatial pattern of WNV infection risk among humans in Italy, focusing on the human cases of West Nile Neuro‐invasive Disease (WNND) observed between 2008 and 2017. Incidence rates are estimated for each year and province under study. The incidence temporal trend is estimated using Poisson regression, and a spatio‐temporal cluster detection analysis is performed to detect high‐risk areas. In total, 231 WNND cases were notified in Italy between 2008 and 2017. The annual incidence rates increased during the study period (annual percentage change: 11.7%; 95%CI: ?0.9%; 26.1%). A geographical spread of the disease was observed during the study period throughout Northern Italy, with an increasing number of affected provinces. Provinces close to the Po River (the main river in the north of Italy) and the Oristano province (in the Sardinia Island) experienced the highest incidence rates during the study period. Our study shows a gradual, but rapid spread of WNND across Northern Italy from east to west and suggests the hypothesis that provinces close to Po River might present ecological and climatic conditions favourable to the virus circulation. 相似文献
23.
24.
Dimova Milena A. Büttner Carmen Gablers Jutta Grosch Rita Bar-Yosef Benayahu Kläring Hans-Peter 《植物病害和植物保护杂志》2010,117(6):244-247
Journal of Plant Diseases and Protection - Pythium aphanidermatum is the most wide-spread root pathogen in greenhouse cucumber. Although environmental condi-tions are known to affect the disease... 相似文献
25.
The objective of this study was to investigate the structural changes of whey proteins during exposure in a continuous-flow UV reactor. Varying UV irradiation dosages were obtained by controlling the flow rate and the mixing speed. Whey protein isolate (WPI) solutions at concentrations of 1% and 5% (w/v) were circulated at flow rates ranging from 30 to 800 mL·min(-1), and changes in physicochemical properties of the proteins were investigated. Intrinsic fluorescence spectra and surface hydrophobicity measurements suggested changes in the tertiary structure of the proteins with UV exposure. The UV treatment also increased the concentration of total and accessible thiol groups in 1% WPI solutions, while no change was measured in 5% WPI solutions. Size-exclusion chromatography demonstrated the formation of UV-induced aggregates and oxidation products (N-formylkynurenine and dityrosine) of aromatic amino acids. Furthermore, the UV-induced changes in protein conformation increased the susceptibility of whey proteins to pepsin hydrolysis. 相似文献
26.
The Swedish tax system affects distribution of forest revenue between national, municipal and individual interests. The study reported here takes a Boreal municipality perspective, with the objective of investigating the tax and investment implications of non-industrial private forestry (NIPF) in a case-study municipality at these three interest levels. Sales revenue, operating costs, investment, disposable income and direct tax revenue generated in NIPF within the boreal municipality are quantified, drawing on income tax return data. The question addressed is, does NIPF contribute to the local economy and thereby to development and maintenance of infrastructure in a typical boreal municipality, given the present NIPF ownership structure and tax system? Results support two different views. On one hand, tax revenues generated from NIPF to the resource municipality amounted to only 17% of the direct tax revenues or less then 1% of the tax revenues in the municipality budget. On the other hand, NIPF owners returned as much as 72% of sales revenue back into their firms in form of operating costs, and 20% in from of investments. 相似文献
27.
Johan Stendahl Sven Snll Mats T. Olsson Peter Holmgren 《Forest Ecology and Management》2002,170(1-3):75-88
The relationship between soil properties and forest site quality was investigated. The site quality functions currently used fail in predicting variations within regions and the purpose of this study was to evaluate if the local accuracy in forest resource assessments could benefit from the use of geological and geochemical data. The investigation was conducted in mid-Sweden within two geological regions. The mineralogy of the parent material (C horizon) was estimated using a method for normative mineralogical assessment and the soil chemistry was determined for five soil horizons. The importance of individual minerals for site quality was different within the two geological regions. Functional relations were established between the properties in different soil horizons and site index. The functions between mineralogy and site index were improved by splitting the data according to the geologically different regions. The mineralogy explained 37–61% of the variation in site index, whereas the properties in the upper soil profile (O–B horizon) related more strongly to site index (18–80%). Stronger relations could be established in the mineralogically rich than in the mineralogically poor area. 相似文献
28.
This study presents a comparative analysis of protected and exploited Mediterranean Sea food webs using standardized ecological models of two ecosystems: the Central-North Adriatic Sea (highly exploited) and the Miramare Natural Marine Reserve (Northern Adriatic Sea, protected since 1986). Food webs are analysed in terms of structural and functional traits including trophic levels, transfer efficiency, trophic role of species and keystoneness, trophic spectra and other synthetic ecological indicators. Our results highlight similarities between food webs of the Adriatic Sea, differences that are likely due to the impact of fishing and differences that should be related to other factors. Analysis of biomass distribution along functional groups and of trophic spectra indicates that protected area presents higher mean trophic level of the community, higher biomasses, lower production and generally lower transfer efficiency than fished area. Our results indicate that measures of food web complexity (system omnivory index and ascendency), as well as pelagic/demersal and fish/invertebrates biomass ratios are higher in the protected area than in exploited ecosystem due to fishing-induced changes. Thus, this study highlights that marine protected areas can efficiently contribute to maintain structural and functional traits of marine ecosystems. 相似文献
29.
Holmgren N Lundeheim N Wallgren P 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1999,46(8):535-544
Two hundred and sixty-four feeder pigs from an age-segregated herd (A-pigs) and 264 feeder pigs from a continuous production system (C-pigs) were transferred into identical but separate rooms in a fattening herd employing all-in all-out production. On arrival, none of the A-pigs and 39% of the C-pigs were seropositive to Mycoplasma hyopneumoniae (M. hyo). At slaughter 30% of the A-pigs and 99% of the C-pigs were seropositive to M. hyo. Pigs with acute swine enzootic pneumonia (SEP) at slaughter and pigs that seroconverted to M. hyo late in the rearing period showed a lower growth rate compared with pigs with chronic SEP or pigs that seroconverted to M. hyo early or not at all. No A-pigs and 12% of the C-pigs were seropositive to Actinobacillus pleuropneumoniae 2 (A. pp 2) at arrival to the fattening herd. At slaughter, 10% of the A-pigs and 13% of the C-pigs were seropositive to A. pp 2. On arrival, the prevalence of pigs seropositive to A. pp 3 was lower among A-pigs than C-pigs. During the fattening period the situation was reversed. The prevalence of pleuritis at slaughter was low (2.7-4.2%) and there were no associations between pleuritis at slaughter and developments of antibodies to A. pp 2 or 3. However, pigs with pleuritis developed antibodies to M. hyo to a greater extent than pigs without pleuritis. Pigs with pleuropneumonia at slaughter and pigs that seroconverted to A. pp 2 or 3 had, during certain periods of the rearing, higher growth rates compared with pigs without pleuropneumonia or pigs that did not seroconvert to A. pp 2 or 3. 相似文献
30.
Costa JF Kiperstok AC David JP David JM Giulietti AM de Queiroz LP dos Santos RR Soares MB 《Fitoterapia》2007,78(7-8):510-514
Ethyl acetate and chloroform extracts from aerial parts of Portulaca werdermannii and P. hirsutissima were tested in lymphoproliferation assays and axenic cultures of Leishmania amazonensis and Trypanosoma cruzi. Both extracts of P. werdermannii and P. hirsutissima had a potent inhibitory activity on lymphocyte proliferation. On the contrary, only the chloroformic extract of both plants inhibited L. amazonensis growth, without effect on T. cruzi cultures. These results indicate these Portulaca species as potential sources of new active molecules for the treatment of leishmaniasis and immune-mediated pathologies. 相似文献