Assessment of Crawler Tractor Effects on Soil Surface Properties

Skidding operations can cause considerable and wide spread soil disturbance. The objective of this study was to evaluate the effects of ground skidding operations on soil compaction, moisture content, and total porosity at different levels of slope and traffic frequency. Four levels of traffic intensity (3, 8, 13, and >13 passes of a Crawler Tractor Onezhets – 110) and three levels of slope ( 20%) were applied to assess soil disturbance. The soil samples from the depth interval 0-10 cm were collected with a soil hammer and rings. Results showed that dry bulk density, moisture content and total porosity were affected considerably by slope and traffic frequency of skid trails. Bulk density was drawing near to the critical value after 8 passes in the trail with the slope >20%; when the number of machine passes increased from 8 to 13 passes, the additional bulk density increment was negligible. Irrespective of traffic frequency, dry bulk density increased significantly in the slope >10% compared to the slope <10%; however there was no significant difference between slopes 10-20% and >20% . Minimum moisture content was measured as 27% on the skid trail versus 47% in the undisturbed area. A negative correlation was found between moisture content and dry bulk density. Total porosity was measured as a maximum 58% to a minimum 44% on the skid trail treatments, and 65% in the undisturbed area. Soil disturbance was extended dramatically on the treatments with slopes >20%, so dry bulk density on the treatments with 8 passes and slopes >20% (1.38 g cm-3) was significantly higher than on the treatment with 13 passes and slopes <10% (1.32 gcm-3). Results showed that slope >10% increased soil disturbance quite dramatically

Effect of logging wounds on diameter growth of beech (Fagus orientalis Lipsky) trees following selection cutting in Caspian forests of Iran

Background Logging damage to residual trees during selection cutting may lead to serious economic losses in terms of both timber quality and diameter growth reduction. In this study, we investigated the effect of logging operations on residual tree damage and the consequence of injuries on diameter growth in an uneven-aged mixed forest dominated by beech (Fagus orientalis Lipsky)

Potential utility of hyperbaric oxygen therapy and propolis in enhancing the leishmanicidal activity of glucantime

In this study we investigated the efficacy of hyperbaric oxygen (HBO) therapy, alone or combined with the pentavalent antimonial glucantime on Leishmania amazonensis infection. In parallel, the effect of Brazilian red propolis gel (propain) alone or combined with glucantime on L. amazonensis infection was evaluated. The inhibition of the infection in macrophages treated with glucantime in combination with HBO exposition was greater than that of macrophages treated with glucantime alone or HBO alone. The susceptible mouse strain BALB/c infected in the shaved rump with L. amazonensis treated with glucantime and exposed to HBO showed: time points in the course of the disease in which lesions were smaller than those of mice treated with glucantime alone and revascularization of the skin in the lesion site; interferon-gamma (IFN-g) levels were not elevated in lymph node cells from these animals. Propain alone was not efficient against lesions, although less exudative lesions were observed in animals treated with propain alone or combined with glucantime. These results reveal the potential value of HBO and red propolis in combination with glucantime for treating cutaneous leishmaniasis and encourage further studies on the effect of more aggressive HBO, propolis and glucantime therapies on different mouse models of leishmaniasis

PREVALENCE, RISK FACTORS AND SYMPTOMS ASSOCIATED TO INTESTINAL PARASITE INFECTIONS AMONG PATIENTS WITH GASTROINTESTINAL DISORDERS IN NAHAVAND, WESTERN IRAN

We studied the prevalence of intestinal parasites (IPs), their risk factors and associated symptoms among patients with gastrointestinal disorders. A total of 1,301 participants aged 22 days-90 years were enrolled in this study. We used a structured questionnaire to obtain socio-demographic and stool examination to investigate intestinal parasite infections. Data analysis was performed using SPSS16. The overall prevalence of intestinal parasites (IPs) was 32.2% (419/1,301). Three hundred and fifty nine cases/1,301 (27.6%) were infected with a single parasite and 60/1,301 cases (4.6%) presented polyparasitism. The most common IP was Blastocystis sp. 350/1,301 (26.9%), followed by Entamoeba coli 38/1,301 (2.92%), Giardia lamblia 30/1,301 (2.3%) and Cryptosporidium spp. 17/1,301 (1.3%). Regarding the socio-demographic variables, educational status (p = 0.001), contact with domestic animals and soil (p = 0.02), age above 15 years (p = 0.001) and seasons (p = 0.001) were significantly associated to intestinal parasitic infections. Concerning clinical characteristics, the presence of IPs was significantly associated to diarrhea (OR = 1.57; CI 95% = 1.24-1.98; p < 0.001) and dysentery (OR = 1.94; CI 95% = 1.03-3.66; p < 0.04). Our findings suggest that IPs are one of the main causal agents of gastrointestinal disorders. Improving the knowledge on local risk factors such as poverty, low level of education, poor sanitation, contact with soil and contact with domestic animal is warranted

Comparison of advanced oxidation methods of Fenton, UV/Fenton, and O-3/Fenton in treatment of municipal wastewater

The present study aimed to evaluate the efficiency of advanced oxidation methods: Fenton, UV/Fenton, and O-3/Fenton in the treatment of municipal wastewater. The effect of H2O2:Fe2+ ratio, pH, and reaction time on chemical and biological parameters: chemical oxygen demand (COD), biological oxygen demand (BOD5), total coliform (TC), and Fecal coliform (FC) were evaluated in different advanced oxidation processes (AOPs) methods (Fenton, UV/Fenton, and O-3/Fenton). All parameters were measured according to the standards methods. The results obtained from the present study showed that the highest removal of pollutants was achieved in H2O2:Fe2+ mole ratio of 0.7:1. Furthermore, the removal of COD, BOD5 were increased when pH increased from 4 to 7. Moreover, reaction time influenced COD, BOD5, TC, and FC until equilibrium time, however, its influence was not significant after equilibrium value. A comparative study on different AOP systems showed the order of highest to lowest removal efficiency of all parameters is as follows: O-3/H2O2/Fe2+ > UV/H2O2 /Fe2+ > H2O2/Fe2+. It can be concluded that Fenton and its modified methods have the promising potential for advanced municipal wastewater treatment