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331.
332.
Francisco J. Baquedano Fernando Valladares Federico J. Castillo 《European Journal of Forest Research》2008,127(6):495-506
The Mediterranean evergreen woody plants Quercus coccifera and Pinus halepensis grow in a range of environments where selection by drought, heat and high irradiance can drive genetic and phenotypic differentiation
of populations. However, the role of these stresses in filtering out maladaptive genotypes remains unknown. We hypothesize
that this filtering is an important process for woody Mediterranean species due to their low phenotypic plasticity reported
in previous studies. We have studied the response of saplings of Q. coccifera and P. halepensis, originating from two contrasting populations (a rock outcrop and a garrigue formation), to water stress. Isozyme characterization
of genetic diversity was done to determine whether populations were genetically distinct. Water response analysis was based
on water relations, gas exchange, chlorophyll a fluorescence, pigment content, antioxidant status and morphological and structural parameters. Ecotypic differentiation was
found for both Q. coccifera and P. halepensis populations, with a higher population isozyme similarity and a higher frequency of dominance of a few genotypes at the rock
outcrop in both the species. P. halepensis exhibited small but significant differences between populations for plastic responses to water, with lower phenotypic plasticity
in saplings from the rock outcrop. Although it was not found in Q. coccifera, this pattern suggests that ecotypic differentiation rendering stress-tolerant ecotypes involves a decreased plasticity. Phenotypic
plasticity was not high but it explained over 75% of the total variability among individual plants. Thus, and although evidence
for ecotypic divergence was found in both the species, saplings were plastic enough to blur ecotypic differentiation.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
333.
Martínez-Sánchez A Gil-Izquierdo A Gil MI Ferreres F 《Journal of agricultural and food chemistry》2008,56(7):2330-2340
A comparative study of antioxidant compounds, flavonoids and vitamin C, and also antioxidant activity was carried out in four species of Brassicaceae vegetables used for salads: watercress ( Nasturtium officinale R. Br.), mizuna [ Brassica rapa L. subsp. nipposinica (L.H. Bailey) Haneltand], wild rocket [ Diplotaxis tenuifolia (L.) DC.], and salad rocket [ Eruca vesicaria (L.) Cav.]. The characterization of individual phenolic compounds by HPLC-DAD-MS/MS-ESI in watercress and mizuna completes the polyphenol study previously reported for wild rocket and salad rocket. The qualitative study of flavonoids in watercress leaves showed a characteristic glycosylation pattern with rhamnose at the 7 position. Isorhamnetin 3,7-di- O-glucoside was identified in mizuna leaves and may be considered a chemotaxonomical marker in some B. rapa subspecies. Brassicaceae species showed differences in the quantitative study of flavonoids, and the highest content was detected in watercress leaves. Watercress and wild rocket leaves had the highest content of vitamin C. The antioxidant activity evaluated by different methods (ABTS, DPPH, and FRAP assays) showed a high correlation level with the content of polyphenols and vitamin C. In conclusion, the Brassicaceae leaves studied, watercress, mizuna, wild rocket, and salad rocket, presented a large variability in the composition and content of antioxidant compounds. These baby leaf species are good dietary sources of antioxidants with an important variability of bioactive compounds. 相似文献
334.
Simone Blanc Cristian Accastello Ettore Bianchi Federico Lingua Giorgio Vacchiano Angela Mosso 《Journal of Sustainable Forestry》2019,38(1):31-45
Fossil fuel consumption in recent decades has caused the rise of CO2 concentration in the atmosphere, with negative consequences on the environment and human health. This study develops a methodological framework to quantify carbon credits from carbon-oriented forest management and evaluates the economic sustainability of their sale. Application of the framework to two forest compartments with long-lasting active management in the Western Italian Alps showed the feasibility of the methodology and provided insights on its replication in other contexts. Particularly, the Carbon-oriented scenario led to a reduction of both the extracted wood volume (10% and 6.5% CASE1 and CASE2, respectively) and Net Present Value (32% and 29%), leading to a carbon credit price of 19.6 € MgCO2eq?1? and 44.1 € MgCO2eq?1 to counteract these losses.
This work allows us to highlight the factors needed to design and evaluate alternative forest management options while considering the consequences of climate change. Moreover, the hypothesized scenarios include an economic remuneration of the positive externalities provided by sustainable forest management.
Finally, the proposed workflow entails undeniable environmental benefits while contrasting climate change but still looks undesirable with respect to the traditional timber-oriented management in compartments where high-quality wood products can be obtained. 相似文献
335.
Ernesto F. Viglizzo M. Florencia RicardEsteban G. Jobbágy Federico C. Frank Lorena V. Carreño 《Field Crops Research》2011,124(2):186-194
Given the increasing number of actors related to farming that make decisions at different scales (plot, farm, region, etc.), knowledge about patterns and processes that behave hierarchically is increasingly needed. This is necessary in countries like Argentina, where cultivation expanded at increasing pace during the last 50 years over an area of 1.47 million km2. Relying on different sources of existing data, the purpose of this work was to assess the cross-scale dependence of patterns and processes related to the expansion of cultivation in Argentina. The study involved indicators of (i) carbon, nitrogen and phosphorous stocks, (ii) energy productivity, fossil energy consumption, C, N and P balances, water consumption and greenhouse gases fluxes, and (iii) impacts related to pesticide contamination, habitat intervention and soil erosion. Three scales involving (i) regions, (ii) macro-regions and (iii) the whole country were analyzed. Principal Components, Correlation and Regression Analysis were used to identify and quantify meaningful relationships between the different scales. The expansion of annual crops affected C-N-P stocks significantly at the regional scale, whereas it influenced energy and matter flows, and contamination across all scales. This finding explains conflictive responses to land use and management when different scales are considered and shows that scale dependency needs to be considered when their effects on the environment are explored and quantified. 相似文献
336.
337.
338.
Gianluigi Mazzoccoli Angelo De Cata Antonio Greco Marcello Damato Nunzia Marzulli Mariangela Pia Dagostino Stefano Carughi Federico Perfetto Roberto Tarquini 《Journal of circadian rhythms》2010,8(1):6
Background
Immunosenescence is a process that affects all cell compartments of the immune system and the contribution of the immune system to healthy aging and longevity is still an open question. Lymphocyte subpopulations present different patterns of circadian variation and in the elderly alteration of circadian rhythmicity has been evidenced. The aim of our study was to analyze the dynamics of variation of specific cytotoxic lymphocyte subsets in old aged subjects. 相似文献339.
Falciglia Pietro P. Biondi Lorena Catalano Roberto Immè Giuseppina Romano Stefano Vagliasindi Federico G. A. 《Journal of Soils and Sediments》2018,18(6):2399-2409
Journal of Soils and Sediments - Localization and quali-quantitative characterization of radionuclide-contaminated soils are essential for healthcare and remediation activities. However,... 相似文献
340.
Sánchez-Margallo FM Soria-Gálvez F Ezquerra-Calvo LJ Usón-Gargallo J 《American journal of veterinary research》2003,64(9):1099-1104
OBJECTIVE: To evaluate the use of ultrasonography to detect morphologic changes in the pylorus during pyloroplasty performed laparoscopically or via conventional abdominal surgery in dogs. ANIMALS: 10 healthy mixed-breed dogs. PROCEDURE: Laparoscopic ultrasonography of the pylorus was performed in 5 dogs during laparoscopic pyloroplasty (LP), and ultrasonography of the pylorus was performed in 5 dogs during pyloroplasty via conventional abdominal surgery (CAP group). Appearance and dimensions of the pyloric sphincter were evaluated by use of a 7.5-MHz flexible laparoscopic linear-transducer probe. RESULTS: Mean +/- SD duration of the ultrasonographic procedure was 11 +/- 3.04 minutes (range, 6 to 18 minutes). In the CAP group, cross-sectional views of the pylorus revealed significant differences between the overall transverse external diameter, overall craniocaudal external diameter, and transverse diameter of the pyloric lumen. After surgery, the pyloric area was significantly increased. Longitudinal views of the pylorus revealed that width of the pyloric ring was significantly less after surgery. Transverse views of the pylorus for the LP group revealed a significant increase in the transverse diameter and craniocaudal diameter of the pyloric lumen after LP. The pyloric area was also significantly increased after surgery. Longitudinal views of the pylorus revealed that width of the pyloric ring was significantly less after surgery. Transverse diameter of the pyloric lumen was significantly increased after LP. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of results of this study suggests that ultrasonography is useful for detecting relevant morphologic changes in the pyloric sphincter after pyloroplasty. 相似文献