Land use effects on phosphorus sequestration in soil aggregates in western Iran.

Cultivating native lands may alter soil phosphorus (P) distribution and availability. The present study aimed to determine the distribution of P in soil aggregates for different long-term land management practices. The partitioned P in labile (L), Fe/Al-bound, Ca-bound, organic pools, and total P in four aggregate size fractions were determined for five land uses (forest, vineyard after 30 years, wetland, alfalfa, and wheat cultivated soil after 20 years). Both native land uses (forest and wetland) were distinguished by high and low amounts of large macro- and micro-aggregates, respectively, compared with disturbed soils (vineyard, alfalfa, and wheat soils). Labile P in large macro-aggregates were higher in native land use when compared with the other land uses, which led to increasing lability of P and accelerated water pollution. Soils under native conditions sequestered more Ca-bound P in large macro-aggregates than the soils in disturbed conditions. Conversion of native lands to agricultural land caused enhanced organic P storage in aggregates smaller than the 2 mm from 31.0 to 54.3%. Soils under forest had 30% total P more than the vineyard for the aggregates >2 mm after 30 years land use change. However, the amount of P in smaller (<2 mm) sized aggregates was increased by 29% for the vineyard when compared with the forest. The P storage as bound Ca particles for the large macro-aggregates had negative correlation with the micro-aggregates.

TU-G-BRB-04: A Robust-CVaR Optimization Approach to Left-Sided Breast IMRT.

PURPOSE: To test the feasibility of a cardiac sparing IMRT planning approach for patients with left-sided breast cancer using a robust optimization model. METHODS: A robust optimization model was developed for breast IMRT. The concept of conditional-value-at-risk (CVaR) was used in the robust framework to guarantee that the clinical dose volume criteria for targets and organs at risk hold under uncertainty in the patient's breathing pattern. Clinical treatment methods for breast cancer (inhale breath-hold with active breathing control (ABC) or free breathing) were simulated via optimization models. A 4DCT patient dataset with target and organs at risk on each breathing phase was used to simulate a clinical case with a total of 20% increase in lung volume from exhale to inhale over 5 phases. The results of the proposed robust model were compared with those of the current clinical models. RESULTS: Compared to the conventional IMRT method for breast cancer (with free breathing), the proposed robust-CVaR model resulted in a 14.6% reduction in mean heart dose without compromising the target coverage and dose homogeneity. The clinical dose-volume limits for the heart as well as the clinical target volume were met in robust results. The robust method resulted in 23.9% improvement in the maximum dose to 25cc of the heart volume. The robust results showed very low variability among the quality of planning and realized treatments. CONCLUSIONS: Using CVaR limits in a robust optimization framework can help improve the quality of IMRT treatments. The robust-CVaR can generate a high quality treatment plans, but is delivered during free breathing and does not require patient compliance with an external device. The quality of robust treatment remains the same under irregular breathing. Explicitly including metrics for lung and bigger motion amplitudes in the robust optimization method may further improve the results.

Effects of probiotics supplementation in daily milk intake of newborn calves on body weight gain, body height, diarrhea occurrence and health condition.

The effects of probiotic administration were studied in an experiment, using 120 newborn calves. Calves were randomly assigned to two experimental groups (sixty calves for each group) and probiotic (0.25 g h(-1) day(-1)) was added in their daily milk intake until 90 days of age. After the first week, all calves (including control group) received starter ration containing 21.0% crude protein and 3.0% crude fat. Body weight gain, body height and general health condition of all calves were observed at day 30, 60 and 90. Also condition of feces was examined daily and the occurrence of diarrhea was recorded throughout the experiment. Mean values of weight gain during three successive months for treatment and control groups were 57.52 and 50.58 kg, respectively. Body weight gained was not significantly different for first and second mo between treatment and control groups (16.9 and 33.87 vs. 14.49 and 33.07 for fist and second months in treatment and control groups, respectively). However, these values were significantly different (p < 0.001) between treatment (57.52) and control (50.58) groups third months of age. Diarrhea was observed in 35 calves of control group, which was higher than 11 cases in calves treated with probiotic (p < 0.001). The body height values of control and treatment groups in three successive months were 5.49, 10.82 and 15.00 cm for control and 5.44, 9.25 and 15.75 cm for treatment groups in first, second and third mo, respectively, which showed no significant difference between two groups during this study. The results of this study indicated that present probiotic compound have beneficial effects, especially on the third month of age in rearing calves.

Response of male buffalo calves to different levels of energy and protein in finishing diets.

A factorial experiment with completely randomised design was conducted, using 27 heads of 15 month buffalo male calves with initial live weight of 287 +/- 15 kg. The animals were individually housed and randomly allocated into 9 treatment groups of three animals each. Three levels of energy (E1, E2, E3) with three levels of crude protein (P1, P2, P3) were formulated to provide 90, 100 and 110% requirement equivalents for 900 g, expected body weight gain of steers derived from NRC beef cattle requirements (1976). Live weight changes were obtained by direct weighing of the animals every month and ended by slaughtering the calves for carcass index measurements. Results indicated that Dry Matter Intake (DMI) was not significantly different between treatments. Average Daily Gain (ADG) ranged from 503 to 951 g/animal that was significantly varied among the diets (p < 0.05). The significantly higher daily gain was obtained (p < 0.05) when animals received medium energy diets that was similar to 100% beef cattle steer requirements. In addition the feed conversion ratio was significantly lower, when the animals received medium energy diets (p < 0.05). The dressing yield as well as the meat % age was not affected by the type of the diet, but abdominal fat was significantly higher in medium energy diets (p < 0.05). It can be concluded that the optimum fattening performance of 15 month old buffalo male calves may be obtained by providing around 10.42 MJ/kg of dietary metabolisable energy and about 10.22% of crude protein.