A mathematical model for wastewater treatment process of an oxidation pond

This study presents a mathematical model for wastewater treatment process (WWTP) of an oxidation pond. The model permits investigating the effects of a biological based product called mPHO on the degradation of contaminants as well as increase the amount of dissolved oxygen (DO) in the pond. At this aim, an ordinary differential equation with coupled equations has been developed to study the correlation between the amount of bacteria (phototrophic and Coliform), chemical oxygen demand (COD), and dissolved oxygen (DO) existing in the pond. The mathematical model is employed to simulate the behaviour of the system where the numerical results demonstrate that the proposed model gives a good approximation of the interaction processes that occur naturally between biological and chemical substances involved in the pond

The effect of endurance training intensity on the expression of perlipin-A protein of visceral adipose tissue, serum glucose and insulin levels in STZ-induced diabetic rats

Background and aims: Changes in the expression of lipid droplet adipocyte proteins, such as prelipipin A (PLINA) cause alter lipolysis and insulin resistance. The aim of this study was to compare the three endurance training intensities (low, moderate and high) on the expression of PLINA protein in visceral adipose tissue, serum glucose and insulin levels in male diabetic Wistar rats. Methods: 40 male Wistar rats were assigned to five groups (n=8) including diabetic group with low intensity endurance training, moderate intensity group, high intensity group, diabetic and healthy control groups. After induction of diabetic rats by injection of streptozotocin, endurance training was performed with different intensities for eight weeks, three sessions per week. The relative expression of PLINA protein was measured by western blot technique. One-way variance analysis and Tukey's post hoc test were used to determine the difference between the groups. Results: The results showed that there was a significant difference between PLINA levels in healthy and diabetic control groups with endurance training groups (with low, moderate and high intensity) (P=0.018). These differences were between low intensity training and healthy control groups (P=0.033) and between diabetic and healthy control groups (P=0.020). Serum glucose and insulin levels were significantly different between the diabetic control and endurance training groups (low, moderate and high) (P=0.001). This difference was between high-intensity training group with low intensity training (P=0.046), diabetic control (P=0.001) and healthy control (P=0.011) groups. Conclusion: Moderate and high intensity endurance training can compensate for the loss caused by diabetes in the expression of the PLINA protein and reduces serum levels of insulin and glucose in these mice. It seems that more intensity endurance training leads to more increase in PLINA expression in diabetic rats

Molecular pathology of 6 novel GJB2 allelic variants detected in familial and sporadic Iranian non syndromic hearing loss cases

Background: Mutations of GJB2 gene encoding connexion 26 are the most common cause of hearing loss in many populations. A very wide spectrum of GJB2 gene mutations associated with hearing loss have been detected but pathogenic role has been tested only for a part of them. In this study, we have provided genetic evidence on the pathogenicity of our previously reported novel GJB2 allelic variants. Methods: The pathogenic role of GJB2 allelic variants were assessed using co segregation of each allelic variant with hearing loss in family members, absence of the allelic variants in control populations, coexistence with a second GJB2 mutation, nature of the amino acid substitution and evolutionary conservation of the appropriate amino acid. Results: The GJB2 allelic variants including 363delC, 327delGGinsA, H16R and G200R have been co segregated with autosomal recessive non syndromic hearing loss in five families and are not found in control subjects. The G130V and K102Q were found in heterozygous state in two deaf individuals. G130V results in an exchange a residue highly conserved among all the connexins but was found with a rate of 1% in control subjects and K102Q results in an exchange a residue not conserved among all the connexins and not identified in control subjects. Conclusion: We conclude that, 363delC, 327delGGinsA, H16R and G200R may be pathogenic. However, the pathogenicity and inheritance of K102Q and G130V can not be assessed clearly and remains to be identified

The effect of droplet size and liquid water content on ice accretion and aerodynamic coefficients of tower legs

An experimental study was conducted to examine the effects of varying the cloud characteristics on ice accretion on tower legs and on the aerodynamic coefficients around the ice-covered legs. First, the variations of droplet size distribution (DSD) and liquid water content (LWC) in vertical and streamwise directions were measured. Then, variations of ice accretion on an angle bar in the same direction as the flow were measured to determine the aerodynamic forces on a tower leg as a function of ice accretion. The ice accretion experiments were carried out under two conditions with different LWCs and air velocities. The drag coefficient was calculated with different masses and ice shapes for the angle bar as obtained in the experiments. The results showed a reduction in the drag coefficient in the vertical direction with increased local LWC and thicker ice accumulation

Effect of 8 weeks resistance training on sphingosine-1-phosphate level and gene expression of SK1 enzyme, isoforms of MHCs in skeletal muscles of male Wistar Rats

Background and Objective: Sphingosine-1-phosphate (S1P) is involved in regulation of proliferation, differentiation, hypertrophy and anti-apoptosis and activation of satellite cells. This study was done to evaluated the effect of 8 weeks resistance training on sphingosine-1-phosphate level and gene expression of SK1 enzyme, isoforms of MHCs in skeletal muscles of male Wistar rats. Materials and Methods: This experimental study was done on Twenty four 8-week-old 190-250 gr male Wistar rats. The rats were allocated randomly into control (N=12) and training (N=12) groups. Resistance training was done using a 1 meter height ladder with 2 cm grid with an 85 degree incline, and weights attached to rat's tails. The content of S1P present in the chloroform layer was determined by means of high performance liquid chromatography (HPLC). Determination of relative mRNA expression was performed by Real-time PCR. Data were analyzed using SPSS-17, Kolmogorov-Smirnov and independent t-test. Results: Resistance exercise training increased the total content of S1P in FHL (fast-twitch) and soleus (slow-twitch) muscles in comparison with control group (P<0.05). Resistance exercise training changed the gene expression of FHL SK1, SOL SK1, FHL MHC I, Sol MHC I, FHL MHC IIa, Sol MHC IIa, FHL MHC IIb, Sol MHC IIb, FHL MHC IIx, Sol MHC IIx in comparison with control group (P<0.05). Conclusion: This study showed that S1P level and gene expression of SK1, MHCs increased at skeletal muscles after training