Search results for "Veterinary Science"

Effect of primary mild stresses on resilience and resistance of the nitrate reducer community to a subsequent severe stress

2008

International audience; The factors regulating soil microbial stability (e.g. resistance and resilience) are poorly understood, even though microorganisms are essential for ecosystem functioning. In this study, we tested whether a functional microbial community subjected to different primary mild stresses was equally resistant or resilient to a subsequent severe stress. The nitrate reducers were selected as model community and analysed in terms of nitrate reduction rates and genetic structure by narG PCR-restriction fragment length polymorphism fingerprinting. Heat, copper and atrazine were used as primary stresses and mercury at a high concentration as a severe stress. None of the primary …

Pressurized hot water extraction (PHWE) for the green recovery of bioactive compounds and steviol glycosides from Stevia rebaudiana Bertoni leaves

2018

Stevia rebaudiana Bertoni leaves are a natural source of diterpenic glycosides, and various bioactive compounds. The objectives were to characterize antioxidants and steviol glycosides in the extracts obtained from Stevia after "green" pressurized hot water extraction (PHWE). PHWE extracts were obtained at different temperatures (100, 130, 160 °C); static extraction times (5 and 10 min), and cycle numbers (1, 2, 3) using a constant pressure of 10.34 MPa. Temperature was the most important parameter for extraction, where the highest recoveries of all bioactive compounds (except for carotenoids) were at 160 °C. Extracts obtained at longer static times had more steviol glycosides, condensed ta…

Give us today our daily bread: The effect of hunger on consumers’ visual attention towards bread and the role of time orientation

2021

Abstract This study investigated the effect of hunger on consumers’ visual attention during a food choice task, and the role of time orientation (i.e., present and future orientation) in this interplay. A lab-based eye-tracking experiment including 102 participants was conducted, with hunger as the manipulated factor (hungry, satiated). Participants in the satiated condition were served a breakfast buffet before the experimental tasks, whereas participants in the hungry condition were served the buffet after completion of the tasks. Both groups were exposed to a set of planograms depicting supermarket shelves and were asked to choose an option they could consider buying, while their eye mov…

Study of the effect of H2S, MeSH and DMS on the sensory profile of wine model solutions by Rate-All-That-Apply (RATA)

2016

The effect of hydrogen sulfide (HS), methanethiol (MeSH) and dimethyl sulfide (DMS) on the odor properties of three wine models-WM- (young white, young red and oaked red wines) was studied. Wine models were built by mixing a pool of common wine volatile and non-volatile compounds and further spiked with eight different combinations of the three sulfur compounds present at two levels (level 0: 0 μg L and level 1: 40 μg L of HS, 12 μg L of MeSH; 55 μg L of DMS). For each wine matrix eight WMs were produced and further submitted to sensory description by Rate-All-That-Apply (RATA) method. Hydrogen sulfide and methanethiol were clearly involved in the formation of reductive aromas and shared th…

Effects of climate, land cover and topography on soil erosion risk in a semiarid basin of the Andes

2016

Understanding soil erosion processes in the Ecuadorian Andes with a tropical wet-dry climate and a variable topography, is fundamental for research on agriculture sustainable, environmental management, as well as for a stable water supply for the local populations. This work proposes method to estimate soil erosion risk in the semiarid Catamayo basin with limited data. The results show that the rainfall distribution and the erosivity along with the rugged topography, followed by the land cover (C-factor), are the most important factors to estimate soil erosion risk. The soil erodibility is the most important factor in the dry season for agricultural areas and where the ground cover is spars…

Crop Coefficient Curve for Paddy Rice from Residual Energy Balance Calculations

2017

AbstractThe crop coefficient (Kc) values of rice paddy are important for estimating accurate rice crop evapotranspiration (ETc), water transfers planning, efficient irrigation management, and hydrological studies. In this study, ETc was measured and a generalized Kc curve was calculated for paddy rice in the Sacramento Valley, California. Field experiments were conducted in three rice paddy fields during the 2011–2013 growing seasons. Surface renewal analysis, after calibration using eddy covariance method, was applied to obtain sensible heat flux values from high-frequency temperature readings; latent heat flux densities were characterized by the residual of the energy balance method. The …

Soil erosion and agriculture

2009

Role of rock fragment cover on runoff generation and sediment yield in tilled vineyards

2017

Summary The soil in conventional Mediterranean vineyards is an active and non-sustainable source of sediment and water. Lack of vegetation cover, small soil organic matter content and intense ploughing result in large rates of erosion in a millennia-old tillage system. There is a need for soil conservation strategies that enable sustainability of wine and grape production; therefore, it is essential to measure the rates and to investigate the processes and factors of soil erosion. This study evaluated factors that can reduce soil losses in traditional Mediterranean vineyards. The investigation was carried out with 96 rainfall simulation experiments at the pedon scale (0.24 m2) to measure so…

Developing an erodibility triangle for soil textures in semi-arid regions, NW Iran

2016

Abstract There is a strong need to develop a simple method for rapid estimation of erodibility using readily available data. In this study, soil erodibility was measured using eleven soil textures at the plot scale (60 cm × 80 cm) on a slope of 9% in a semi-arid region. A total of 110 soil erosion experiments were conducted using ten simulated rainfalls (50 mm h− 1 for 30 min). A regression model was developed based on silt and clay content (R2 = 0.82, p

Comparing different application procedures of the water drop penetration time test to assess soil water repellency in a fire affected Sicilian area

2019

Abstract The Water Drop Penetration Time (WDPT) technique was applied in two subsequent years (2016 and 2017) to check surface soil water repellency (SWR) in a Sicilian mountain area affected by a wildfire on June 2016. A total of 93 sites were sampled and from 3 to 100 droplets were used to characterize a site. The detected SWR varied with the severity of the wildfire, being practically absent in the unburnt control area and slight to extreme in the burnt areas. The percentage of extremely repellent sites increased with wildfire severity. SWR vanished one year after the passage of the fire in sites where fire severity was moderate but it persisted in the case of a severe wildfire. In gener…