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This study investigated the feasibility of large-scale utilizing calcareous wastes (CW) of Angoran lead and zinc mine as aggregates in mortar production with the maximum possible substitution of natural aggregates. The main goal was to produce mortar (concrete with fine aggregates as fine as sand or smaller) from Angoran mine's calcareous wastes for maintenance in its underground spaces. Compared to concrete, such mortars with better fluidity can enter narrow spaces more easily. In addition, it can be used to build various structures around the mine. Therefore, multiple samples were prepared by replacing 0% (as the control sample), 20%, 40%, 60%, 80%, and 100% of natural aggregates with CW. Subsequently, compressive strength, flexural strength, water absorption, slump, and TCLP tests were conducted on these samples. The results revealed that the mortar sample with 80% CW exhibited significantly higher compressive strength at 3, 14, 28, and 56 days compared to both the control sample and other samples. Specifically, the compressive strength of this sample reached 35.5 MPa at 56 days, representing an 18.4% increase over the control sample. This indicates that the hydration of cement and the growth of C-S-H gel were enhanced. Analysis of the workability and slump of the samples indicated that as the percentage of natural aggregate replaced by CW increased, the fluidity of the mortar slightly decreased. In addition to mechanical properties like compressive strength, environmental aspects like heavy metal stabilization are also very important. So, TCLP tests conducted on the four heavy metals lead, zinc, copper, and cadmium demonstrated that the released amounts of these elements from all the samples were below the EPA standard limits. These findings confirm the effective stabilization of heavy metals in mortar samples. A comparison of SEM images revealed that the mortar sample made with 20% CW (with minimum compressive strength) exhibited a higher presence of ettringite compared to the sample made with 80% CW (with maximum compressive strength) after 28 days., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The aim of this study was to investigate the characteristics of yogurt prepared with the addition of Persian shallot and probiotic bacteria. The effect of Persian shallot on the viability of probiotic bacteria ( Lactobacillus acidophilus and Bifidobacterium bifidum ) was evaluated. Furthermore, the antimicrobial effects of shallot and probiotic bacteria on Listeria monocytogenes and Escherichia coli species were investigated. The experiments were performed on days 0, 1, 7, 14, and 21. The results showed that the survival of lactic acid bacteria increased significantly in the presence of shallots ( p  < .05). The addition of two different probiotic bacteria to the yogurt samples inhibited the pathogenic bacteria. While E. coli bacteria had a 3-log reduction, L. monocytogenes did not grow at all in the presence of probiotic bacteria and shallots. Based on these experiments, it was concluded that the addition of shallots not only increased the survival of probiotic bacteria but also reduced the growth of food-borne pathogenic bacteria. In addition, the addition of probiotic bacteria increased the acceptance of sensory properties of yogurt samples., Competing Interests: There is no conflict of interest., (© 2024 The Authors. Food Science & Nutrition published by Wiley Periodicals LLC.)

Jugular vein blood samples collected from 5 Holstein-Friesian cows during the luteal phase of the estrous cycle were incubated at 4 C, 22 C, and 37 C for 0, 0.5, 1, 2, 4, 6, 8, 12, and 24 hours. Blood samples were centrifugated after each incubation period, and plasma was frozen for later progesterone assay. Mean progesterone concentration in blood samples incubated at 4 C, 22 C, and 37 C decreased from 5.7 ng/ml at 0 hour to minimum concentrations of 3.5 ng/ml at 12 hours, 0.9 ng/ml at 12 hours, and 1.0 ng/ml at 8 hours, respectively. The first progesterone concentration which was significantly different from the initial value (0 hour) was at the 8-hour incubation period for blood samples incubated at 4 C and at the 1-hour incubation period for blood samples incubated at 22 C and 37 C. Progesterone concentration decreased similarly when blood samples were collected into heparinized tubes or EDTA tubes and incubated at 22 C for 0, 6, and 12 hours. Incubating harvested plasma or serum for 0 to 6 hours at 37 C had no effect on progesterone concentrations (7.9 and 8.2 ng/ml for plasma, and 6.9 and 6.6 ng/ml for serum.

The nature of progesterone decline in samples of bovine blood as affected by whole blood incubation time and temperature was investigated in 3 experiments. In 2 experiments, progesterone concentrations were determined in plasma, in hemolyzed (by freezing and thawing) blood, and in washed blood cells and blood cell washes before and after 8 hours of incubation at 22 C to study the effect of RBC on detected progesterone. In the third experiment, the effect of alteration in RBC metabolism on progesterone degradation by these cells was studied by using potassium oxalate-sodium fluoride as anticoagulant. Results of these experiments indicated that (a) progesterone was significantly reduced because of whole blood incubation time and temperature, (b) lost progesterone was not detectable on or in blood cells indicating chemical degradation of progesterone, (c) intact blood cells were needed to obtain the decrease in the progesterone, (d) a small amount of circulating blood progesterone was associated with blood cells, and (e) degradation of bovine blood progesterone by blood cells was dependent on the glycolytic process. Potassium oxalate-sodium fluoride anticoagulant and refrigeration provided the best progesterone results when blood samples were not processed immediately after collection.