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51.
FJF Sant'Ana JL Reis Junior GR Blume EJ Gimeno F Rey HH Ortega 《Reproduction in domestic animals》2015,50(2):327-332
The expression of growth factors was evaluated immunohistochemically in normal and cystic ovaries of sows. The immunohistochemically stained area (IHCSA) was quantified by image analysis to analyse the expression of these proteins in the follicular wall of secondary, tertiary and cystic follicles. IGF‐I immunoreactivity was strong in the granulosa cell layer (GC), moderate in the theca interna (TI) and mild in the theca externa (TE) of the normal follicles. There was severe reduction of the labelling to IGF‐I in the GC of the follicular and luteinized cysts. In the normal follicles, the reactivity for IGF‐II was very similar to pattern noted in IGF‐I. There was reduction of the IHCSAs in the GC of the follicular and luteinized cysts, but the decrease was not significant. The staining of the IGF‐II in the TI and TE of the cysts was increased, in comparison with normal follicles. The IHCSAs for VEGF were higher in the GC and TE of the normal follicles in contrast to TI, but this difference was noted only in the tertiary follicle. The VEGF reactivity increased in the GC of the cysts, in relation to normal follicles. The results of the current study show that the formation of ovarian cysts in sows is associated with alterations in the immunohistochemical expression of some growth factors. 相似文献
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53.
R. Baños‐Gómez N. S. Cruz‐Cansino T. Suarez‐Diéguez C. Valadez‐Vega E. Ramírez‐Moreno E. Alanís‐García J. A. Ariza‐Ortega J. J. Manríquez‐Torres E. Zamora‐Romo L. Delgado‐Olivares 《Journal of animal physiology and animal nutrition》2017,101(2):267-274
Undernutrition induces an increase of the oxidative stress that can predispose offspring to various diseases in adulthood through epigenetic reprogramming. The aim of this study was to evaluate the effects of intergenerational undernutrition on protein oxidation and antioxidant defence response on liver, heart and brain of the second‐generation neonates (F2) of undernourished rats. For this purpose, both parents in parental (F0) and first generation (F1) were fed with a low‐nutrient diet. Body mass and length decreased (p < 0.05) in F0, F1 and F2 being the F1 males who exhibited a greater mass loss. A decrease in plasma albumin concentration was observed in F2 neonates (p < 0.05) and also a mass loss of liver, heart and brain (p < 0.05), although proportionally to body length reduction. Undernutrition increased levels of protein oxidation in liver and heart (p < 0.05) but not in brain (p > 0.05) while catalase activity increased only in brain (p < 0.05). In summary, intergenerational undernutrition modifies the antioxidant status through an organ‐specific response, on F2 neonate rats, where the brain increased catalase activity to prevent a severe oxidative damage and support the vital functions of this key organ to maintain vital functions. 相似文献
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55.
Energy analysis of irrigation delivery systems: monitoring and evaluation of proposed measures for improving energy efficiency 总被引：1，自引：1，他引：1
M. A. Moreno J. F. Ortega J. I. Córcoles A. Martínez J. M. Tarjuelo 《Irrigation Science》2010,28(5):445-460
In Spain, the Ministry of Industry is implementing actions for analyzing the energy efficiency of Water User Associations
(WUAs) by using energy indicators and proposing measures to improve the use of energy. The main objective of this work was
to develop tools to improve energy efficiency in WUAs. These tools were validated by utilizing them in the energy analysis
of 15 WUAs located in Castilla-La Mancha Region (Spain) during the 2007 irrigation season. These tools were also utilized
for the proposal of measures to improve the use of energy. The proposed measures were monitored and evaluated in 7 of the
15 WUAs during the 2008 irrigation season. The developed tools were integrated into a Decision Support System for performing
energy analysis and for proposing measures of energy efficiency improvement. In most of the study cases, an improvement of
the energy efficiency after the implementation of the proposed measures was detected, with an average energy saving of the
10.2%. 相似文献
56.
L. F. Madrin A. Etter G. D. Boxall A. Ortega‐Rubio 《Land Degradation u0026amp; Development》2007,18(2):199-208
Alluvial forests are under high pressure from human activities because of their value as agricultural, wildlife, timber and recreational land. Despite this, spatial patterns of alluvial forest deforestation are not well known. We studied forest alterations in a 2800 ha alluvial ecosystem using aerial photographs. During the study period (1939–1997), forests with canopy heights greater than 15 m (high canopy mature forest; HCM forest) decreased by 70·4 per cent while forests with canopy heights less than 15 m (low canopy mature forest; LCM forest) forests decreased by 51 per cent, producing a highly fragmented landscape. Factors responsible for forest change included human activities and river dynamics. Although most of the deforestation was related to human disturbance, almost 27 per cent of forest losses were due to channel migration of the Meta River. HCM forests were the most affected land cover since they are easily accessed, viable for logging and occurred on fertile soils, which are valuable for agriculture. LCM forests were less affected since their soil fertilities and inundation regimes were unfavourable to human uses, and thus, less prone to anthropogenic disturbances. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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58.
Gustavo Riveros;Rocío Soria;Ana Villafuerte;Paloma Gómez;Raúl Ortega;Isabel Miralles;Mauricio Schoebitz; 《Soil Use and Management》2024,40(1):e12991
Microplastics (MPs) are a significant threat to soils. However, there is scarce information on the impact of MPs on soil properties, particularly in volcanic ash-derived soils. The objective of this study was to evaluate the impact of polyamide (PA) and low-density polyethylene (LDPE) MPs on the biological and chemical characteristics of an Andisol from central Chile. Twenty-one parameters were evaluated, including pH, electrical conductivity (EC), total organic carbon (TOC), dissolved organic carbon (DOC), total phosphorus (TP), available phosphorous (AP), available nitrogen (AN), inorganic nitrogen forms (NH4+, NO2− and NO3), carbohydrates (CHO), polyphenols (POLs), humic substances, soil basal respiration (SBR) and activities of soil enzymes such as dehydrogenase, β-glucosidase, phosphatase and urease. For this, a microcosm was set up in clay pots in an incubation chamber at 21°C and 60% soil moisture, with the addition of PA and LDPE at doses of 1% and 3% w/w; a control treatment consisting of microcosm without MPs was also included. After 6 weeks of incubation, PA addition resulted in an increase in TOC and NH4+ by up to 32% and 26%, respectively, and a decrease in NO3− by 22%. AP decreased by 15%–19% with the addition of PA and LDPE. Similarly, acid phosphatase and β-glucosidase activities decreased by 15% and 26% with PA and LDPE, respectively. The distance-based linear model (DistLM) was used to analyse relationships in chemical and biological datasets. The analysis revealed that TOC and TP were primary components in the best model for predicting microbiological changes (R2 = .469, AICs = 16.026), indicating that MPs accumulation affects soil carbon cycling and P content. Overall, the results show that MPs addition alters soil chemical and microbiological properties in Andisols, with varying effects depending on the type and dose of MPs, with the highest dose (3%) producing the most marked negative effects. 相似文献
59.
I. Miralles R. Ortega G. Almendros F. Gil‐Sotres C. Trasar‐Cepeda M. C. Leirós M. Soriano 《European Journal of Soil Science》2012,63(2):272-283
Soil organic matter composition and biochemical properties were determined in mountain calcimorphic Mediterranean soils under different vegetation (cultivated soils, secondary bush, high mountain bush, juniper, evergreen oak and pine) to assess the impact of soil use on the size and activity of microbial communities. Our results indicated that clearing forest leads to a general decline in the performance of soil organic carbon sequestration and associated enzymatic activities. However, when soil enzymatic activities (dehydrogenase, catalase, phosphodiesterase, β‐glucosidase, urease and casein‐protease) were expressed as ratios to total organic carbon (specific activities), a conspicuous increase in their activities was observed in cleared soils as compared with forest soils, suggesting enhanced hydrolytic potential in the former. In addition, the negative correlation observed between qCO2 (metabolic quotient) and water retention at ?1500 kPa, could be interpreted as an adaptive strategy against low soil moisture by microbial communities in cleared soils. This indicates the importance of describing soil quality in terms of long‐term soil organic C sequestration and/or resistance of the organic matter to microbial transformation. These features were reflected in the visible and infrared spectra of humic acids, which suggested humification mechanisms involving mainly an alteration of plant macromolecules with poor incorporation of characteristic microbial metabolites in the forest soils whereas the opposite effect was observed in cleared soils. 相似文献
60.
Miguel A. Ortega Huerta 《Biological conservation》2007,134(1):83-95
Patterns of fragmentation in current distributions of 35 species of birds and 19 species of mammals that are considered endangered, threatened, or with restricted distributions were modeled in relation to 3 biosphere reserves (El Abra-Tanchipa, El Cielo, Sierra Gorda; ‘BRs’) and 13 areas identified as priorities for conservation in northeastern Mexico (PAC-Priority Areas for Conservation). Core area percentage of landscape (CPLAND) and aggregation index (AI) were used to summarize fragmentation trends in species’ geographic distributions, modeled using ecological niche modeling techniques. Overall (median) CPLAND and AI revealed: (a) for birds, El Abra-Tanchipa BR and neighboring areas exhibited the lowest fragmentation (high CPLAND and high AI), whereas Sierra Gorda BR was the most fragmented; (b) for mammals, El Abra-Tanchipa and El Cielo BRs exhibited lowest overall fragmentation, while Sierra Gorda BR was the most fragmented. Although there were areas (i.e., El Abra-Tanchipa BR and Parras de la Fuente PAC) with higher combination of CPLAND and AI values, El Cielo BR stands out because of its high CPLAND and AI values along with the highest species richness. 相似文献