Journal of School of Public Health and

Background and Aims: In this study we measured the quality, corrosiveness, Ryznar stability index, and heavy metal leakage in the drinking water distribution networks of Ahvaz.

Materials and Methods : A total of 76 sampling sites were selected for this purpose the sites included inlet and outlet points in water treatment plants as well as consumers taps. We collected 456 samples in six stages and over a period of six month, following the procedures outlined in the Standard Method. Data were analyzed using the SPSS 11.5 software package.

Results: The average values obtained from the specimens were as follows: temperature (19 0C), turbidity (1.97NTU), pH (7.31), pHs (7.88), EC (1678µs/cm), TDS (1006mg/l), Alkalinity (129mg/l), Calcium (109mg/l), DO (6.78mg/l), Cl- (293mg/l), SO4-- (264mg/l), Ryznar stability index (8.43). Average heavy metal levels in tap water were as follows: Pb (8.48µg/l), Cd (0.972 µg/l), Zn (3.18 mg/l), Cu (0.168 g/l), Fe (0.257 mg/l), and Mn (0.031mg/l).

Conclusion: The results showed that the water quality has been affected in such a way as to cause corrosiveness, heavy metal leakage and aesthetic problems. We also showed that in comparison with USEPA and Iranian standards, the quality indices of the drinking water in Ahvaz were at an acceptable level, with the notable exception of a few indices such as TDS, EC, and hardness. The Ryznar stability index indicated that the drinking water in Ahvaz has corrosive properties and this could be one of the reasons behind the high rates of heavy metal leakage detected in this area.

Background and Aim: Determination of the age of vector mosquitoes is of particular importance in epidemiological studies of diseases transmitted by them, such as viral and parasitic diseases. The objective of this study was to determine the daily age of Anopheles stephensi based on changes in pteridine concentration in female mosquito cuticles by liquid chromatography (HPLC).

Methods and Materials: Females of Anopheles stephensi were raised in an insectary (28° C, 70% relative humidity). At 1, 5, 10, 15, 25, 30 days post-emergence they were divided into groups of 10 mosquitoes each. The mosquitoes in each age group were further divided into 3 subgroups of 10 each for chromatographic (HPLC, emotion = 355 nm and excitation= 465 nm) pteridine extraction. The chromatograms obtained were compared with the respective standards to determine the types of pteridines.

Results: Four types of pteridines were detected in the cuticle of Anopheles stephensi, including isoxanthopteridine, pteridine-6-carboxylic acid, biopteridine, and xanthopteridine. They were all present in all the cuticle of the mosquitoes however, no biopteridine in the head or xanthopteridine in the thorax were found. Generally, as the age of the mosquitoes increased, pteridine concentrations kept declining, such that after 30 days the total concentration reached 10% of the original.

Conclusion:The findings indicate that there is a negative correlation between the concentration of pteridines in the cuticle and daily age of female mosquitoes. The method described can be used as a standard method to determine the daily age of Anopheles, as well as of other mosquito species, since it is fast and precise and needs small samples. Its major limitation is non-availability of HPLC in many parts of the country, although it is possible to freeze dead mosquitoes and transfer them to centers where HPLC is available.

  Background and Aim: Considering the uncertainties about associations between orexin-A and obesity, the present study was conducted to determine the effects of 8 weeks of endurance training and high intensity interval training ( HIIT) on plasma levels of orexin-A and some anthropometric parameters in obese adolescent boys.

  Materials and methods: In this semi-experimental project 35 healthy, inactive and obese boys (mean age 15.5±0.69 years, mean body mass index (BMI) = 28.72±2.20, equal to or higher than the 95^th percentile) were randomly divided into three groups of equal numbers, namely, control, endurance training, and HIIT. The endurance training and the HIIT group participated in eight weeks of endurance training (25-40 minutes running per day, with an intensity 65-85% Heart Rate Reserve) and eight weeks of HIIT (30 seconds running with an intensity 90-95% Heart Rate reserve, 4-7 repetitions a day and two minutes of a rest interval with 50-55% Heart Rate reserve), three days per week, respectively. Plasma levels of orexin A, anthropometric measurements (waist-to-hip ratio, body fat percentage and body mass index) and VO2 max were determined before and 48 hours after the last session of the training. Data were analyzed and are reported as mean ± SD using repeated measure ANOVA (p < 0.05).

  Results : Despite a decreasing trend in the plasma orexin-A level in the control and HIIT groups and its rising trend in the endurance training group, no statistically significant differences were observed between the control and experimental groups (P>0.05). However, HIIT and endurance training caused significant reductions in the anthropometric parameters such as body fat percentage (8.7%, 9.7%), body mass index (1.6%, 1.9%) and waist to hip ratio (2.7%, 2.9%), accompanied by a significant increase in the VO2 max (6.7%, 10.9%) (p<0.05).

  Conclusion: Endurance training is more effective than HIIT as regards improvement in body composition of obese adolescent boys, although the changes may not be in line with changes occurring in plasma orexin-A levels. It is recommended that more studies be conducted in this area, controlling sleep, nutrition and changes due to puberty, and with longer durations of exercise.