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91.
The main goal of this study was to propose a reliable method to verify the geographical origin of meat, establishing the influence of soil and water on its isotopic and elemental composition. Thus, beef meat, soil, and water samples were collected from three major cattle-producing regions of Argentina (Buenos Aires, Córdoba, and Entre Ríos). Multielemental composition was determined on these three matrices by inductively coupled plasma mass spectrometry (ICP-MS), δ(13)C and δ(15)N by isotope-ratio mass spectrometry (IRMS), and the (87)Sr/(86)Sr ratio by thermal ionization mass spectrometry (TIMS). Soil and drinking water samples could be characterized and clearly differentiated by combining the isotopic ratios and elements, demonstrating differences in geology and climatic conditions of three regions. Similarly, meat originating at each sampling area was characterized and differentiated using only five key variables (Rb, Ca/Sr, δ(13)C, δ(15)N, and (87)Sr/(86)Sr). Generalized procrustes analysis (GPA), using the three studied matrices (soil, water, and meat) shows consensus between them and clear differences between studied areas. Furthermore, canonical correlation analysis (CCA) demonstrates significant correlation between the chemical-isotopic profile of meat with those corresponding to both soil and water (r(2) = 0.93, p < 0.001; and r(2) = 0.83, p < 0.001, respectively). So far, there are clear coincidences between the meat fingerprint and those from soil/water where cattle grew, presenting a good method to establish beef provenance. To the authors' knowledge this is the first report linking the influence of soil and water all together on the composition of beef, presenting the basis for the authentication of Argentinean beef, which could be extended to meat from different provenances.  相似文献   
92.
Gallic acid (GA) is widely distributed in various plants and foods and has various biological properties including anticancer effects. In this study, we investigated the effects of mitogen-activated protein kinase (MAPK) [MAP 20 kinase or ERK kinase (MEK), c-Jun N-terminal kinase (JNK), or p38)] inhibitors or small interfering RNAs (siRNAs) on GA-induced HeLa cell death in relation to reactive oxygen species (ROS) and glutathione (GSH) levels. GA dose dependently inhibited the growth of HeLa cells via apoptosis and/or necrosis at 24 h, which was accompanied by the loss of mitochondrial membrane potential (MMP; ΔΨ(m)). Treatment with 70 μM GA increased the ROS level including O(2)(?-) and significantly induced GSH depletion in HeLa cells. GA decreased the activity of extracellular signal-regulated kinase (ERK) at 24 h, whereas it increased that of JNK at the same time. While the MEK inhibitor or ERK siRNA did not affect cell growth and death in 70 μM GA-treated HeLa cells at 24 h, JNK and p38 inhibitors enhanced cell growth inhibition and death in these cells. Additionally, p38 siRNA administration augmented growth inhibition, death, and MMP (ΔΨ(m)) loss in 70 μM GA-treated HeLa cells. In relation to ROS and GSH levels, JNK and p38 inhibitors increased ROS levels, and GSH-depleted cell numbers in GA-treated HeLa cells. Moreover, p38 siRNA increased O(2)(?-) levels and GSH depletion in GA-treated HeLa cells. Each MAPK inhibitor and siRNA differentially affected ROS and GSH levels in HeLa control cells. Conclusively, JNK and p38 inhibitors and p38 siRNA enhanced growth inhibition and cell death in GA-treated HeLa cells, which were to some extent related to GSH depletion and ROS levels, especially O(2)(?-).  相似文献   
93.
ABSTRACT

Maize production is affected by water and nitrogen (N) deficit either separately or joined, but this fact is not completely defined. The aim was to evaluate the fate of N in maize fertilized and subjected to water stress in controlled conditions. A greenhouse experiment was carried out at the University of Buenos Aires campus. The design was a 2 × 2 factorial with four replications. The factors were N: 70 and 140 kg N ha?1 as labeled urea (15N), and water: 100% or 50% of the potential evapotranspiration. The harvest of aerial and root biomass was carried out at R1 stage. Nitrogen in plants, soils nitrate, ammonia volatilization, and 15N percentage were determined. Obtained results only partially agree with previous research. Water stress depressed aerial biomass production independently of N doses. When water was limiting, the uptake of N from fertilizer was independent of N. When water was not limiting, N uptake increased with the higher N doses. Volatilization losses were 3.7 to 7.8% of N applied as fertilizer. Plant N recovers was around 45% of the N applied, except in treatment water stressed with high N rate (19%). Nitrate-N from the fertilizer in the soil at harvest and accumulated N from the fertilizer in plant were lineally related (r2 = 0.54; p < 0.001). Important destinations of N were accumulation in plant, volatilization and incorporation into soil organic matter. However, residual nitrate was a main fate in heavily fertilized and water deficit treatment. This process could lead to the eventual nitrate leaching.  相似文献   
94.
Genetic Resources and Crop Evolution - The wild vine Vitis tiliifolia (Humb &amp; Bonpl. Ex Schult.). is found in Mexico, Central América, and the Caribbean region. In the Veracruz State,...  相似文献   
95.
Most research on the mycorrhizal positive–negative responsiveness continuum (or “mutualism–parasitism continuum”) has focused on individual plant species growing at different levels of P availability. Here, we explore this continuum in an experimental plant community inoculated with three arbuscular mycorrhizal (AM) fungal strains (both single and mixed) growing under four resource availability scenarios. These scenarios are a factorial combination of two levels of water and N availability. Each AM fungal strain had a different origin: an arid ecosystem, a farmland, and a mine. We hypothesized that the response of the plant community to mycorrhizal inoculum would depend on the associated AM fungal strain and would be negatively related with increased nitrogen and water availability. Our results showed that mixed‐strain AM fungal inoculation had more positive effects along a wider range of water and N availability scenarios than single‐strain inoculation. In contrast, mycorrhizal growth response of plants inoculated with a single AM fungal strain shifted from positive to neutral and negative depending on resource availability. Adaptation of each strain to its local conditions might confer different properties to the mycorrhizal symbiosis. Therefore, we conclude that AM fungal origin and environmental limiting resources are crucial factors to predict plant community mycorrhizal growth response in changing ecosystems.  相似文献   
96.
A tomato cultivar with high quality fruit and a long shelf life is a main goal in tomato breeding and it would be achieved using wild germplasm. The objective of this work was to explore the inheritance for fruit quality traits, especially fruit shelf life, in three tomato crosses using a standard Argentinean cultivar (Ca, cv ‘Caimanta’), a ripening mutant (nor, homozygous for the nor gene) of Solanum lycopersicum, and a wild cherry type (Ce, LA1385 of S. lycopersicum var. cerasiforme). The wild parent had a shorter fruit shelf life than the mutant genotype but higher than Ca. When the Ce genotype was analyzed in hybrid combination, the F1 (Ca×Ce) was similar to the wild genotype for shelf life whereas the F1 (nor × Ce) had a longer shelf life. Both F1 crosses and backcrosses to the cherry type genotype had significantly lower fruit weight than the cultivated genotypes but higher than the cherry type parent. In the F2 analysis, it was found that the inheritance underlying quality traits is complex since non allelic interactions were detected. A significant additive genetic variance was found for fruit shelf life as well as for other fruit quality traits in each cross. The genetic parameters analyzed by mean values and variances in parental, F1 and F2 and backcross generations indicated that the cross between the normal ripening cultivar and LA1385 of S. lycopersicum var. cerasiforme offers the best possibility to obtain long shelf life tomato genotypes with good fruit quality.  相似文献   
97.
The impact of agroforestry on food security of upland farmers is least recognized and appreciated given that the linkage between them is quite complex and not well understood. The crucial role of agroforestry in enhancing food supply and augmenting family income is commonly ignored. This study aimed to get a deeper understanding of the role of agroforestry in ensuring food security of farming households in the Philippine uplands. A combination of participatory approaches including participatory rural appraisal, household survey, focused group discussions, field experiments and simulation modeling were used for the study conducted in Claveria, Northern Mindanao, Philippines. The first major finding was that the prime responsibility for ensuring adequacy of food production and supply for the farming households rested on the husband and wife. The second major finding based on the simulation results was that agroforestry increased and stabilized corn yields under hedgerow system. Moreover, fruits from perennial crops and trees served as secondary food crops especially during lean months of food supply. The last major finding was that the adoption of agroforestry significantly increased the level of benefits by around 42–137%, compared with the low income from continuous annual monocropping. The key to making upland farm households food secure is to increase the productivity of their farms and home gardens. A good start is to promote the agroforestry system in upland areas, and it is thereby recommended that both national and local government units mainstream their policies and efforts toward promotion of agroforestry adoption in the Philippine uplands.  相似文献   
98.
The inland region of Galicia (NW Spain) marks the boundary between the Atlantic climate of the coastal area and the typical Mediterranean climate of central Spain. Compared to the Atlantic coast, climate in this area has a pronounced summer drought, lower annual precipitation, and higher annual thermal oscillation. Despite the high productivity and ecological importance of maritime pine in inland Galicia, local forest reproductive material (FRM) of high genetic quality is not available for this area. Seed sources originating elsewhere and of unknown adaptation to this area are commonly used for reforestation. With the aim of finding new sources of FRM for this region and exploiting the genetic gains of existing breeding programmes, we analysed the performance in field conditions of improved families of the Coastal Galicia (CG) and Western Australia (WA) breeding programmes. Growth, stem characteristics and branch habit were evaluated in five progeny trials established following a coastal-to-inland gradient. Likelihood-based analyses were used to estimate genetic correlations between environments and to test statistically for causes and patterns of genotype × environment interaction. Because of the strong non-random spatial structures and heterogeneity of residual variances, the analyses were carried out using heterogeneous residual variance mixed models on spatially adjusted data. The results indicated that there is not sufficient evidence to subdivide Galicia into the two current deployment areas. Interaction patterns do not reveal significant differences between zones, and crossover interactions for height growth are present both between and within areas. On the inland sites, the Atlantic improved materials clearly outperformed unimproved seedlots tested in adjacent provenance trials, suggesting the feasibility of using both the CG and WA breeding materials as sources of FRM for reforestation in inland Galicia. Of the two, the WA material showed excellent results for all traits. The inclusion of this material into the Galician maritime pine breeding population should be strongly considered.  相似文献   
99.
The study was carried out to examine morphological and physiological effects of different levels of fat in compound extruded feed for carp. A 90 days experiment was performed in tanks with water flow 0.34 L min?1, stocked each with 29 specimens of carp, average weight 15.4 ± 4.2 g. The fish was fed 3 diets containing 38 % protein and 8, 12 or 16 % of fat (feed L8, L12, and L16, respectively). Body weight gain, specific growth rate, food conversion ratio, feed efficiency ratio, condition factor, liver and intestine histology and morphometry and some blood biochemical parameters were analysed. At the end of the experiment, a difference was established between the fish fed L8 feed compared to carp fed L12 and L16 feed for all growth parameters. For several other parameters, nuclear area of hepatocytes, nuclear/cytoplasm ratio, enterocytes height and intestinal folds’ length, a difference between carp fed feed L8 compared to feed L16 was found. The histological analysis revealed that normal structure of the liver and intestine prevailed, but changes were observed regardless of the diet type. In the hepatopancreas, more prominent changes were found around pancreatic tissue—particularly, increased number and size of adipocytes. Although blood biochemical parameters were within normal values, a difference between L8 and L16 diet-fed carp was found for plasma levels of triglycerides and total proteins. According to the results obtained in this study, the best results were achieved using a feed with 8 % fat.  相似文献   
100.
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