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Many decisions must be made under stress; therefore, stress and decision-making are intrinsically related not only at the behavioral level but also at the neural level. Additionally, virtual reality tools have been proposed as a method to induce stress in the laboratory. This review focuses on answering the following research question: Does stress assessed by physiological variables of a subject under virtual reality stimuli increase the chances of error in decision-making? The reviewed studies were consulted in the following databases: PubMed, IEEE Xplore, and Science Direct. The analysis of the consulted literature indicates that the stress induced in the laboratory using virtual reality tools and the physiological response of the central and autonomous nervous system are complementary subjects and allow the design of training and support systems for the decision-making process. [ABSTRACT FROM AUTHOR]

Broiler males (n= 140) were used in a straight-run experimental design and distributed randomly among four treatment groups with seven replicates per treatment and five broilers per replicate. During 21-42 d old, the chickens were fed iso-caloric and iso-nitrogenous diets containing four levels of dietary vegetable oils (DVO), of 2.7, 4, 6 and 8%. During d 25-27, 31-33, and 38-40 of age, broilers were exposed to heat stress for 4 h a day (1000-1400 h) at 34 °C, 70-75 % relative humidity. Feeding an 8% DVO diet significantly increased body weight gain compared to the other DVO levels. The feed conversion ratio, protein conversion ratio, metabolizable energy conversion ratio and European production index were significantly enhanced due to feeding an 8% DVO diet compared to a diet containing 6% DVO. Feeding 8% DVO significantly increased the meat protein and lipid percentages, compared to the control group (2.7 % DVO), but decreased the plasma low-density lipoprotein, very-low-density lipoprotein and lymphocytes. Feeding 8% DVO significantly increased the mean cell volume and mean cell hemoglobin, and bursa weight and percentage compared to the control. In addition, 6 and 8% DVO significantly increased the plasma total antioxidant capacity compared to the control group, but decreased the malondialdehyde. Thus, broilers fed a diet containing 8% DVO have an increased tolerance to heat stress, as evidenced by increasing the productive performance, meat quality, blood hematological and biochemical traits, antioxidants and immunity. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the variability of photosynthetic pigment content and daily stomatal conductance was evaluated in relation to environmental variables in Copoazú (Theobroma grandiflorum) ecotypes. The ecotypes used were part of the germoplasm bank of the University of the Amazon (Colombia). The study was carried out during the year 2015. Four leaves of the average stratum of four plants were collected for each ecotype, to extract and read at different levels of absorbance and determine the content of photosynthetic pigments. During the hours of 04:00 a.m. to 6:00 p.m., the stomatal conductance (gs) was monitored for environmental variables (relative humidity, air temperature, radiation and vapor pressure deficit (VPD). An analysis of variance was made using the Tukey test, correlations and regressions were made between gs and environmental variables. The contents of chlorophyll a, b, total and carotenoids among ecotypes were different (P<0.0001), the ecotype UA-31 presented the highest values, contrasting with the ecotype UA-37. Concerning gs, the interaction ecotype*hour showed significant differences (P<0.0001). The ecotypes that presented the highest values of gs were UA-67 and UA-039, (P<0.0001), radiation (-0.91, P<0.0001) and DPV (-0.94; P<0.0001) 0.0001).The results suggest that ecotypes UA-039 and UA-31 were the most suitable in terms of gaseous exchange and content of photosynthetic pigments. [ABSTRACT FROM AUTHOR]

This work was conducted in "La Hampa" experimental farm, belonging to the Institute of Natural Resources and Agrobiology of Seville (CSIC), Spain, in order to evaluate the physiological responses elicited by traditional (LT) and conservation tillage (LC) on the nutritional status of wheat crop (Triticum durum L.) in long-term experiments on a sandy clay loam Xerofluvent soil. The experimental area has an agrometeorological station to record the minimum, average and maximum values of different variables, considering temperatures and rainfall in this work. A randomized block design with three replicates per treatment was used for the study; each block had a surface area of 240 m2. At the experimental stage, crop nutrient extraction was assessed on the grains and leaf mass of 10 randomly selected plants per treatment. Nitrogen was determined by Kjeldahl method whereas the other elements by plasma atomic emission spectroscopy (ICP). From the physiological point of view, there are significant differences on the extraction of nutrients absorbed by the crop, ensuring that plants had no nutritional problems at the conservation tillage, with an increased total dry mass production. No significant differences were detected between both treatments with respect to yield, so that conservation tillage is more appropriate when taking into account its environmental benefits. [ABSTRACT FROM AUTHOR]