Surfactant-enhanced Bioremediation of n-Hexadecane-contaminated Soil Using Halo-tolerant Bacteria Paenibacillus glucanolyticus sp. Strain T7-AHV Isolated from Marine Environment

A halo-tolerant bacterial strain Paenibacillus glucanolyticus sp. strain T7-AHV isolated from marine environment was used for bioremediation of n-hexadecane-contaminated soil. Soil/water ratio, initial inoculums volume, surfactant addition, n-hexadecane concentration, and salinity were investigated. The possibility of biosurfactant production by isolated strain was also studied, and the results demonstrated that it was not a biosurfactant producer, based on measurement of the surface tension of culture broth. Both tween 80 and rhamnolipid enhanced the biodegradation of n-hexadecane significantly up to 44 and 46 %, respectively. A biodegradation rate of 39.7 % was observed at salinity level of up to 2 %, and the biodegradation efficiency decreased significantly at higher salinity concentrations. A natural hydrocarbon-contaminated soil sample with total petroleum hydrocarbon (TPH) concentration of 1437 mg kg–1 was subjected to bioremediation using the selected conditions of operational parameters, and a biodegradation rate of 22.1 % was obtained

A two-dimensional inverse heat conduction problem for estimating heat source

This note considers the problem of estimating unknown time-varying strength of the temporal-dependent heat source, from measurements of the temperature inside the square domain, when the prior knowledge of the source functions is not available. This problem is an inverse heat conduction problem. In this process, the direct problem will be solved by using the heat fundamental solution. Then a sequential algorithm is developed to solve a Volterra integral equation, which has been produced by using unknown source term and overposed data conditions. This algorithm is based on the piecewise linear continuous functions. The performance of the present technique of inverse analysis is evaluated, by means of several numerical experiments, and is found to be very accurate as well as efficient. 1

Do Conocarpus erectus airborne pollen grains exacerbate autumnal thunderstorm asthma attacks in Ahvaz, Iran?

A disastrous outbreak of thunderstorm-induced asthma attacks posed a major public health threat in Ahvaz, Iran in autumn of 2013 (>15,000 referrals to hospital emergency rooms and pulmonary clinics). City officials claimed that promoting factors included acid rain, particulate matter, ozone, and polycyclic aromatic hydrocarbon compounds (PAHS) could lead to this phenomenon. After these potential causes were rejected by careful research, the next possible cause that this study addresses is a potential link of the asthma attacks to airborne pollen grains and fungal spores. In order to sample these parameters, a Hirst-type volumetric spore sampler was used, which was installed on the rooftop of the sampling site. Sampling was done during two six-month periods to characterize the regional bioaerosol. The first period included the autumn (September 22 to December 20 of 2016) and winter seasons (December 21 of 2016 to March 19 of 2017), while the second period included the following autumn (September 23 to December 21 of 2017) and winter seasons (December 22 of 2017 to March 20 of 2018). In both studied periods, airborne weed pollen grains, especially Amaranthaceae sp., were by far the greatest contributor to total airborne pollen grain concentrations (50.45, 3757 pollen grains/m3 and 52.12, 2392 pollen grains/m3, respectively). Among fungal spores, Cladosporium had the highest concentrations (75.29, 258677 spores/m3 and 80.33, 247693 spores/m3, respectively). Findings also showed that concentrations of airborne pollen grains were higher in autumn seasons (6361 and 4167 pollen grains/m3, respectively) in comparison with winter seasons (1085 and 423 pollen grains/m3, respectively), while the concentrations of fungal spores were enhanced in winter seasons (189216 and 160962 spores/m3, respectively) versus autumn seasons (154377 and 147377 spores/m3, respectively). Fungal spores exhibited a uniform distribution during the entire study period, but airborne pollen grains were significantly higher in autumn seasons. The numbers of referrals associated with thunderstorm asthma attacks decreased drastically after implementing Conocarpus erectus tree pruning activities. We concluded that the autumnal thunderstorm asthma attacks in Ahvaz might be triggered by a combination of bio-allergens (fungal spores and airborne pollen grains such as from Conocarpus erectus) and high levels of air pollutants from industrial activity. The results of this work suggest controlling bio-allergen levels by preventive measures such as tree pruning, weed removal, and emasculating urban green infrastructures before the flowering season. © 2019 Elsevier Lt

Study of the association of mutant HBsAg gene and Hodgkin and non-Hodgkin lymphoma

Background: Hepatitis B Virus (HBV) is responsible for chronic, acute, and fulminant hepatitis, which are prevalent worldwide. Chronic HBV may lead to cirrhosis and hepatocellular carcinoma. Several epidemiological studies have indicated that hepatitis B virus is involved in B-cell Hodgkin and Non-Hodgkin Lymphoma (NHL).Objectives: The aim of this study was to evaluate the association between hepatitis B infection and Hodgkin and non-Hodgkin Lymphoma.Materials and Methods: Paraffin embedded of 41 block samples including 12 (29.26%) Hodgkin and 29 (70.73%) non-Hodgkin patients were collected. Next, DNA extraction was carried out for all the samples followed by HBV DNA detection by the nested polymerase chain reaction (PCR). The positive HBV DNA samples were sequenced, and HBV genotypes and HBV subtypes were determined.Results: Three out of 12 (25%) Hodgkin samples and seven out of 29 (24.13%) non-Hodgkin showed positive HBV DNA results. The results of sequencing revealed that the D genotype was predominant among the positive HBV patients. Interestingly an unpredictable amino acid proline was detected in position 88 of the HBs gene, which indicates a new mutation in the “S” region of HBV DNA in patients with Hodgkin and non-Hodgkin lymphoma. Conclusions: A high rate of 25% and 24.13% of HBV DNA was detected among patients with Hodgkin and non-Hodgkin lymphoma, respectively. © 2015, Ahvaz Jundishapur University of Medical Sciences