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21.
Pietro P. C. Aucelli Massimo Conforti Marta Della Seta Maurizio Del Monte Lorenzo D'uva Carmen M. Rosskopf Francesca Vergari 《Land Degradation \u0026amp; Development》2016,27(4):1075-1092
This paper focuses on the analysis of the slope and catchment erosion dynamics in a typical Mediterranean context and its sensitivity to recent climatic and socio‐economic changes. The main objective of the present study is to test the reliability of digital photogrammetric analysis to evaluate the time and space evolution of erosion processes mainly triggered by surface running waters and landslides for about the last 60 years. The selected test area is the Landola catchment, a minor tributary of the Upper Orcia River Valley (Southern Tuscany). The Upper Orcia valley is a key site for the comprehension of denudation processes typically acting in Mediterranean badland areas thanks to the following: (i) the availability of long‐lasting erosion monitoring datasets (20 years' long direct measurements at erosion ‘hot spots’); (ii) its representativeness as a sub‐humid Mediterranean badland area; and (iii) the rapidity of development of erosion processes, which makes it suitable as an open‐air laboratory for the study of badland dynamics. The outputs of this work highlight that the application of high‐resolution digital photogrammetric methodologies can represent a powerful and low‐cost tool to evaluate rates and spatial–temporal distribution of denudation processes, as confirmed by the validation through field point monitoring in areas close to the study area. The results obtained for the study area confirm that high erosion rates are a persistent environmental problem for the Upper Orcia Valley, which is not solved up to now, despite various land conservation interventions. The performed multi‐temporal analysis shows a slight decrease in the average water erosion rate during the last 60 years and a parallel increase in the frequency of mass wasting events. These variations are most likely related to a complex interplay between land use changes that have affected the study area during the studied period, revealing a very delicate equilibrium between farming activities and erosion processes. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
22.
Barbarita Companioni Mayda Arzola Yania Rodríguez Marais Mosqueda María Cristina Pérez Orlando Borrás José Carlos Lorenzo Ramón Santos 《Euphytica》2003,130(3):341-347
Banana and plantain are among the most important food crops in developing countries but production is threatened by increasing
virulent forms of Fusarium oxysporum f. sp. cubense. Chemical control is not economically effective and,therefore, breeding programs are necessary. Traditional field studies
of new genotype resistance to this disease are time-consuming and destructive. Therefore,we developed a rapid and non-destructive
procedure to differentiate field-grown banana resistant from susceptible clones. This procedure implicates application of
culture filtrates of Fusarium oxysporum f. sp. cubense race 1 onto banana leaves. The relationship between duration of the fungal in vitro incubation, and the fungal culture fresh mass, the culture filtrate absorbency, and the Gross Michel (susceptible cultivar)leaf
lesion area (after application of the culture filtrate) were similar and at 24day-incubation the highest values of the recorded
indicators were observed. A comparison between Gross Michel and FHIA-01(resistant) was also performed. The most relevant differences
between cultivars were observed at 48 hours after application of the culture filtrate, and in the middle-aged leaves. The
position of the culture filtrate application in the leaf limb (distal, middle, proximal) was not determinant. A wider comparison
among banana cultivars confirmed previous results informed by other researchers using different systems to study this plant-fungus
interaction. Such a confirmation validates the effectiveness of the procedure described here to select rapid and non-destructively
banana resistance to this disease at field level.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
23.
24.
Lorenzo C Pardo F Zalacain A Alonso GL Salinas MR 《Journal of agricultural and food chemistry》2005,53(19):7609-7616
The red grapes co-winemaking effect on phenolic fraction and wine color has been studied for the first time, where Monastrell was comacerated and cofermentated with Cabernet Sauvignon and Merlot. Changes in the relative abundance of anthocyanins were observed as well as hyperchromic shifts at 530 and 620 nm; these effects remain constant after aging. Co-winemaking also favored copigmentation, giving way to more stable anthocyanins and facilitating their polymerization. With regard to color evolution, the mixture of Monastrell with Merlot grapes was more appropriate than with Cabernet Sauvignon for aging wines in oak barrels. The extent of copigmentation was more important in young wines than in aged wines. This is mainly due to the self-anthocyanin monomer reactions in the case of young wines, whereas in aged wines copigmentation is mainly due to the reaction between the anthocyanins and other polyphenolic cofactors. Discriminant analysis showed the possibility of differentiating wines according to the aging time and the type of wine, with color parameters (color intensity, OD 620 nm, and OD 520 nm) being the most important discrimination variables in the first case and petunidin-3-glucoside and peonidin-3-glucoside contents in the second case. 相似文献
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26.
Llorenç Grau-Roma Lorenzo Fraile Joaquim Segalés 《Veterinary journal (London, England : 1997)》2011,187(1):23-32
Post-weaning multisystemic wasting syndrome (PMWS) emerged as a significant disease affecting pig production in the 1990s although the causal agent, porcine circovirus type 2 (PCV2), and the disease itself, had existed in swine for many years prior to this. The important multifactorial ‘triggers’ of PMWS include the immune and infection status of the sow, the timing of PCV2 infection, variations in the virulence of PCV2, co-infections, immune modulation as well as host genetics and management factors. In terms of diagnosis, histopathological examination and the detection of PCV2 within lymphoid tissue remains the ‘gold standard’ as quantitative PCR techniques are currently not specific or sensitive enough. The recent commercial availability of PCV2 vaccines provides an excellent tool for reducing the impact of PMWS and other porcine circovirus-related diseases. This review assesses recent advances in the epidemiology, diagnosis and control of PMWS. 相似文献
27.
Season appears to influence the physiology of bottlenose dolphins (Tursiops truncatus). From 2000 to 2005, blood parameters of three captive bottlenose dolphins housed in northern Italy were examined to determine if seasonal variation was present. Seasonal variation was observed in the male dolphins, with both males exhibiting aminotransferase levels that were higher in autumn and lower in winter. Mean serum creatinine levels were higher during summer and lower during autumn in the adult male, and mean lactate dehydrogenase higher during summer and lower during spring in the juvenile male. Both males exhibited red blood cell counts and hemoglobin levels that were higher during autumn and lower during summer. This study contributes to the knowledge of baseline hematologic and biochemical values based on seasonality in bottlenose dolphins. 相似文献
28.
Cocchi M Foca G Lucisano M Marchetti A Pagani MA Tassi L Ulrici A 《Journal of agricultural and food chemistry》2004,52(5):1062-1067
Different kinds of cereal flours submitted to various technological treatments were classified on the basis of their mid-infrared spectra by pattern recognition techniques. Classification in the wavelet domain was achieved by using the wavelet packet transform for efficient pattern recognition (WPTER) algorithm, which allowed singling out the most discriminant spectral regions. Principal component analysis (PCA) on the selected features showed an effective clustering of the analyzed flours. Satisfactory classification models were obtained both on training and test samples. Furthermore, mixtures of varying composition of the studied flours were distributed in the PCA space according to their composition. 相似文献
29.
30.
Iglesias MT De Lorenzo C Del Carmen Polo M Martín-Alvarez PJ Pueyo E 《Journal of agricultural and food chemistry》2004,52(1):84-89
With the aim of finding methods that could constitute a solid alternative to melissopalynological and physicochemical analyses to determine the botanical origin (floral or honeydew) of honeys, the free amino acid content of 46 honey samples has been determined. The honeys were collected in a small geographic area of approximately 2000 km(2) in central Spain. Twenty-seven honey samples were classified as floral and 19 as honeydew according to their palynological and physicochemical analyses. The resulting data have been subjected to different multivariant analysis techniques. One hundred percent of honey samples have been correctly classified into either the floral or the honeydew groups, according to their content in glutamic acid and tryptophan. It is concluded that free amino acids are good indicators of the botanical origin of honeys, saving time compared with more tedious analyses. 相似文献