Physical and biological removal of diesel oil from contaminated soil was studied in a baffled roller bioreactor. Initially, the effects of four factors (soil loading, temperature, pH, and surfactant) on physical removal of diesel oil were investigated. Only the presence of a surfactant (sodium dodecyl sulfate [SDS]) demonstrated a significant effect on diesel oil removal. Diesel oil removal efficiency was increased from 32.0% to 63.9% in the presence of 100 mg/L SDS. Using a microbial culture enriched from contaminated soil, biological treatment of diesel oil polluted soil under different soil loadings (15% to 50%), different diesel oil concentrations (1 to 50 g/L), and different types of soil (sand, silt, and clay) was then investigated in the baffled roller bioreactor. Biodegradation consisted of both fast and slow stages for degradation of light and heavy compounds, respectively. All biodegradation experiments demonstrated significant decreases in diesel oil concentrations (88.3% in 14 days for initial diesel oil concentrations of 1000 mg/L and a wide range of soil loadings). The presence of silty or sandy soils enhanced the biodegradation rate compared to the control bioreactor (without soil). The sandy soil loading had no effect on the biodegradation results. Using the enriched culture, the baffled roller bioreactor was able to biodegrade high diesel concentrations (up to 50 g/L) with biodegradation rates of 112.2 and 39.3 mg/L· h during fast and slow stages, respectively. 相似文献
The effect of microbial control of souring on the extent of corrosion was studied in a model system consisting of pure cultures of the nitrate-reducing, sulfide-oxidizing bacterium (NR-SOB) Thiomicrospira sp. strain CVO and the sulfate-reducing bacterium (SRB) Desulfovibrio sp. strain Lac6, as well as in an SRB consortium enriched from produced water from a Canadian oil reservoir. The average corrosion rate induced by the SRB consortium (1.4 g x m(-2) x day(-1)) was faster than that observed in the presence of strain Lac6 (0.2 g x m(-2) x day(-1)). Examination of the metallic coupons at the end of the tests indicated a uniform corrosion in both cases. Addition of CVO and 10 mM nitrate to a fully grown culture of Lac6 or the SRB consortium led to complete removal of sulfide from the system and a significant increase in the population of CVO, as determined by reverse sample genome probing. In the case of the SRB consortium addition of just nitrate (10 mM) had a similar effect. When grown in the absence of nitrate, the consortium was dominated by Desulfovibrio sp. strains Lac15 and Lac29, while growth in the presence of nitrate led to dominance of Desulfovibrio sp. strain Lac3. The addition of CVO and nitrate to the Lac6 culture or nitrate to the SRB consortium accelerated the average corrosion rate to 1.5 and 2.9 g x m(-2) x day(-1), respectively. Localized corrosion and the occurrence of pitting were apparent in both cases. Although the sulfide concentration (0.5-7 mM) had little effect on corrosion rates, a clear increase of the corrosion rate with increasing nitrate concentration was observed in experiments conducted with consortia enriched from produced water. 相似文献
Programmed cell death-1 (PD1) is an inhibitory receptor expressed on the activated T and B cells. Binding of PD1 to its ligands, PD-L1 and PD-L2 has led to deliver an inhibitory signal into the activated T cells. Recently, blocking PD1/PD-L1 pathway has emerged as a new treatment paradigm across a broad spectrum of malignancies. Remarkable clinical responses of monoclonal antibodies specific for PD-1 or its ligands in patients with many different types of cancer, attracted several pharmaceutical companies and researchers to investigate the agents that block PD1/PD-L1 signal. The safety and efficacy of the agents are needed to examine in the preclinical studies. In this study, we optimized a facile and cost-effective protocol for in vitro generation and functional analysis of human PD1/PD-L1 pathway. Activation of CD8?+?CD279?+?T cell was performed by anti-CD3 and D28 antibodies and the recombinant PD-L1 was used for inactivation of T cells through PD1/PD-L1 pathway. In this protocol, T-cell cytokine production (IL-2 and IFN-γ) and proliferation assay confirmed that a measurable PD1/PD-L1 signal was generated. We expected that in vitro PD1/PD-L1 signal that has been optimized in this study will serve as a valuable protocol for preclinical studies involving PD1/PD-L1 pathway. 相似文献
There are diverse relationships between mites and birds or mammals. These mites may play an important role in epizootics and in the perpetuation of some significant diseases. The purpose of this study is to revise the current knowledge of mesostigmatic mites occurring on birds, including their nests and mammals and their substrates, in Iran and to compare the results with other regions of the Palearctic ecozone. This study presents a revised list of 38 species of mesostigmatic mite occuring on birds (17 species) and mammals (24 species) or in their nests/substrates in Iran. Dermanyssus gallinae, Ornithonyssus sylviarum and Parasitus hyalinus were found on both birds and mammals. The species composition of mites reported in Iran was compared with other regions of the Palearctic ecozone. Parasites, specifically those from genera Dermanyssus, Ornithonyssus and Liponyssoides, may be hazardous to human health. Species from these genera were predominant among the reported mites. 相似文献
The study presents length‐weight relationships (LWRs) and length‐lenght relationships (LLRs) for two freshwater fish species from the Cheshmeh‐Langan River (Iran; 32°50′N, 50°04′E), a part of the Tigris drainage basin. Fish were sampled by electrofishing (Samus 725M) in August and September 2017. The LWRs and LLRs obtained showed a high level of correlation (r2 > .98). 相似文献
Pogonolaelaps
gen. n. a new genus of Laelapidae Berlese is erected and described based on Pogonolaelapscanestrinii (Berlese), comb. n. as well as on specimens which were collected from soil and ant nests in different parts of Iran. Also, a new species Pogonolaelapsbeaulieui
sp. n. is described based on specimens collected from soil, litter and ant nests in various parts of Chaharmahal va Bakhtiari province, Iran. The genus Gymnolaelaps is revised considering species with some morphological deviations. Gymnolaelapsreniculus (Karg, 1981) and Gymnolaelapstriquetrus (Karg, 2003) are removed from this genus and placed in their original genus Pseudoparasitus. The characters of Laelaspisella Marais & Loots, 1969 are discussed in a detail along with a proposal of a new definition. 相似文献
Manure-inhabiting Mesostigmata mites are important biological control agents of pest flies. However, the biodiversity of this mite community is mainly known from Europe and America, and especially from cattle manure. This study examined the diversity and abundance of Mesostigmata mites associated with various types of manure in an (intensive) agricultural region of the Middle East, i.e., the city Ahvaz and its suburbs, in southwest Iran. Mite samples were extracted from manure of cattle, buffalo, sheep, horse, poultry and quail in 30 livestock and poultry farms. In total, 40 species belonging to 24 genera and 16 families were identified. The most diverse families were Laelapidae with eight species, Macrochelidae with seven and Parasitidae with six. Macrocheles muscaedomesticae and Uroobovella marginata were the most widespread species, recorded in 28 and 27 out of 30 collection sites, respectively. Two species, M. sumbaensis and U. marginata, were found in all studied manures. Simpson’s diversity index recorded the highest diversity in buffalo and sheep manure. Real and theoretical species richness (rarefaction curves) were congruent in number of individuals. The presence of seven species of Macrochelidae in the manure confirms that these are important predators of the house fly for the region of Ahvaz and its suburbs. Members of the Parasitidae were highly prevalent, with one species known as a specialized predator of house fly eggs. This work aims to encourage further studies on the diversity of Mesostigmata in these agricultural settings, and further continue assessing the feasibility of these mites as effective biocontrol agents of filth flies in different types of manure and from different corners of the world.