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Background and Objectives: In order to increase efficiency and productivity, the need to use high-energy concentrate in dairy cows' rations seems to be essential. This type of feed increases the risk of subacute ruminal acidosis, which leads to reduced dry matter intake, milk production, and fat content. Therefore, different types of buffers are used to reduce the above consequences. Most buffers used in livestock farms include sodium carbonate, potassium bicarbonate, potassium carbonate, potassium bicarbonate, magnesium oxide, magnesium carbonate, and bentonite. Scientific reports on rations containing buffers have a significant effect on fermentation parameters such as volume of gas production, potential, and consistent rate of gas production. Materials and Methods: In this study, three types of rations for dairy cows composed of 50:50, 40:60, and 30:70 forage to concentrate ratios and 4 types of buffers and alkalizer including sodium bicarbonate, sodium carbonate, potassium carbonate, and magnesium carbonate were examined using in vitro technique. The sequence of this experiment included determining the initial pH, buffering capacity, and buffering value index, determining the effect of buffers on the rate of fermentation parameters, microbial production, and utilizable crude protein at the duodenum of different diets in terms of forage to concentrate ratios. Results: The results of this experiment showed that the highest acidogenicity value was related to the treatment of low forage rations containing sodium bicarbonate buffer, which was significantly different from the control treatment. The rate of microbial protein production, in the gas technique, indicated that the highest amount of microbial protein was produced in the low-forage ration containing sodium bicarbonate buffer. In the microbial protein production experiment, it could be used in the small intestine. The highest amount of protein that could be used in the small intestine at eight and Twenty-four hours was related to the treatment of low forage feed containing sodium bicarbonate buffer. Conclusion: The results of treatments indicated that the buffering capacity of sodium carbonate, potassium carbonate, and magnesium carbonate was significantly higher than sodium bicarbonate. The use of sodium bicarbonate and potassium carbonate buffers in low-forage diets increase gas production and production of microbial protein. It seems that among the evaluated compounds, sodium bicarbonate and potassium carbonate have the best effect on the production of microbial protein and utilizable crude protein at the duodenum in different diets in terms of the ratio of forage to concentrate. [ABSTRACT FROM AUTHOR]

Purpose: Recovery after intense interval training plays an important role in improving athletic performance, while the type of recovery and exercise background can affect athletic performance. The aim of this study was to compare the Response of blood buffering capacity to three types of recovery during Repeated High-Intensity endurance test in trained and untrained girls' students of Farhangian University.Methods: 30 female students of Farhangian University (mean age 22.49 ±.3 (year), weight 68.33 ± 7.31 (kg) and height 176.76 ± 8.32 (cm) were randomly selected in three recovery groups (active: N=10, passive: N=10, Stretching: N=10) randomly. The Subjects underwent three types of recovery during the repeated high-intensity endurance test after evaluating the maximum oxygen consumption according to a specific pattern in a crossover methods, three days in a week. Arterial blood sample were taken measured before and immediately after the test and buffering capacity and carnosine were analyzed by ABG and ELISA techniques. After 8-eight weeks of aerobic exercise (65-80% of maximal heart rate), the test and blood sampling were repeated with the same pre-test and at the same time.Results: In untrained girls, only significant difference was found between stretching and active recovery for oxygen saturation, and in trained girls' there was a significant increase in oxygen saturation for active and passive recovery. Significant increase in blood acidity, bicarbonate, base buffers and carnosine was observed in trained girls by active recovery (P ≤ 0.05).Conclusion: The results show that the response of buffering capacity to the three types of recovery was significantly higher in trained subjects. Which is more notable with active recovery.

Purpose: Recovery after intense interval training plays an important role in improving athletic performance, while the type of recovery and exercise background can affect athletic performance. The aim of this study was to compare the Response of blood buffering capacity to three types of recovery during Repeated High-Intensity endurance test in trained and untrained girls' students of Farhangian University. Methods: 30 female students of Farhangian University (mean age 22.49 ±.3 (year), weight 68.33 ± 7.31 (kg) and height 176.76 ± 8.32 (cm) were randomly selected in three recovery groups (active: N=10, passive: N=10, Stretching: N=10) randomly. The Subjects underwent three types of recovery during the repeated high-intensity endurance test after evaluating the maximum oxygen consumption according to a specific pattern in a crossover methods, three days in a week. Arterial blood sample were taken measured before and immediately after the test and buffering capacity and carnosine were analyzed by ABG and ELISA techniques. After 8-eight weeks of aerobic exercise (65-80% of maximal heart rate), the test and blood sampling were repeated with the same pre-test and at the same time. Results: In untrained girls, only significant difference was found between stretching and active recovery for oxygen saturation, and in trained girls' there was a significant increase in oxygen saturation for active and passive recovery. Significant increase in blood acidity, bicarbonate, base buffers and carnosine was observed in trained girls by active recovery (P ≤ 0.05). Conclusion: The results show that the response of buffering capacity to the three types of recovery was significantly higher in trained subjects. Which is more notable with active recovery. [ABSTRACT FROM AUTHOR]

In this investigation, the surface chemical properties of the beech wood layers were characterized and the impact of drying condition on the strength of the bond was examined. Defect free beech logs were harvested and then the layers were prepared. The moisture content of the specimens were adjusted at 30, 40 and 50% (dry basis) and then the specimens were air dried under the environment of 30% relative humidity and 21ºC to reach the equilibrium moisture content of about 10% (dry basis). The pH and buffering capacity of the surface layer and the layer 0.5 mm underneath the surface were measured. The dried specimens were bonded using urea-formaldehyde resin and the tensile strength and wood failure were measured using relevant ASTM method. The results showed that as the moisture content prior to air drying was increased, the tensile strength was reduced, but the effect of this variable on tensile strength was not statistically significant. However, the effect of moisture content on wood failure was statistically significant at 99% significance level. The effect of the pH of the under layer on both tensile strength and wood failure was statistically significant at 95%. As the moisture content of the wood increased, the pH of the surface layer increased and the strength of the bond with urea-formaldehyde resin was deteriorated. At higher initial moisture of the wood, the alkaline buffering capacity of the surface layer was lower and its effect of the strength was not statistically significant, but it was significant on wood failure at 99% level. The alkaline buffering capacity of under layer was also changed and statistically affected the bond strength and wood failure at 95% level. The higher alkaline buffering capacity of the under layer adversely affected the tensile strength of the bond. The lowest acid buffering capacity was measured from specimens with 40% initial moisture content and as the acid buffering capacity was increased, the tensile strength was reduced and the wood failure was higher. The impact of surface layer acid buffering capacity on tensile strength was on statistically significant, but on wood failure was statistically significant at 99% level.

Purpose: The aim of this study was to investigate the prediction of aerobic and anaerobic capacity from lactate relative change during isocapnic buffering phase in elite athletes. Methods: eight endurance and six sprint elite cyclists participated in the present study and performed one standard incremental test and a supramaximal exercise test on a cycle ergometer until exhaustion in 2 separate sessions. During the incremental test Breath-by-breath measurement of respiratory gas was performed and during the last 30 seconds of each 3-minute stage, blood samples were collected for lactate measurement. Lactate threshold (LT) and respiratory compensatory threshold (RCT) were defined as abrupt increase in blood lactate concentration in lactate - workload and abrupt increase in CO2 respiratory equivalent. Isocapnic buffering phase was defined as the time between LT and RCT. Two independent sample t-test was used for all comparison between groups and the relationship between variables was measured by Person correlation test. Results: lactate relative changes during isocapnic buffering phase in anaerobic cyclists were significantly higher than endurance group (p