[Characteristics of Microplastic Present in Urban Road Dust].

Microplastics (MPs), as an emerging contaminant, have attracted wide attention due to their potentially negative impact on the ecosystem. However, information on microplastic pollution in terrestrial environments, especially road dust, is still rare. In this study, the microplastic pollution in road dust from the Yushan District of Ma'anshan City was characterized. The abundances of MPs accumulated per square meter of road and dust were (18.11±32.36) n·m-2 and (223.00±197.01) n·kg-1, respectively, and the contents were (27.29±72.64) mg·m-2 and (385.23±628.93) mg·kg-1, respectively, with polypropylene (PP, 58.90%) and polyethylene (PE, 30.08%) as the major polymers based on the number fraction in dust. Additionally, in a given road area, the abundance of MPs in commercial areas was the highest[(78.32±101.24) n·m-2], followed by residential[(19.81±14.30) n·m-2], industrial[(10.95±5.54) n·m-2], suburban[(8.56±8.13) n·m-2], and educational[(6.99±5.74) n·m-2] areas. In the case of the same area, the microplastic pollution from the commercial area was heavier. Regarding the shape of the MPs detected in road dust, 66.64% were present as films, 16.14% as granules, 14.13% as fibers, and 3.10% as spheres out of the total number detected. Most of the MPs were less than 1000 µm in size. For a particular road area, the abundance of MPs was significantly correlated with the mass of dust (r=0.599, P<0.01), whereas there was no obvious correlation for the mass of MPs (r=0.067, P=0.780). Generally, the road dust can accumulate continuously prior to cleaning, whereas the mass of the MPs will not increase unless there is external input. Otherwise, MPs on the road will be broken down under the action of external forces such as vehicles, resulting in an increase in the number of MPs.

[Synergy of Algal Sedimentation and Sediment Capping for Methane Emission Control in Bloom Waters].

This study tested a strategy in simulated column systems to control methane emissions from algal bloom waters using the combined technology of algae sedimentation and sediment capping. The results demonstrated that the synergy of algal sedimentation and sediment capping can effectively improve the water environment and reduce methane emissions; however, the improvement rate differed among capping materials. The use of activated carbon yielded better performance on the water environment improvement and methane emission control than soil and zeolite. Compared with the control system, the dissolved oxygen and redox potential in the water were increased from<2.5 mg·L-1 to 3.1 mg·L-1 and from<100 mV to 174 mV, respectively. In addition, the redox potential in the surface sediment was reversed from -125 mV to 168 mV after algal sedimentation with subsequent activated carbon capping. As a result, methane emissions in the algal sedimentation-activated carbon capping systems were decreased by 90.2% over the incubation period relative to the control system. This study provides useful insights into methane emission control in eutrophic waters.

Polymorphism of IFN-γ +874T/A associated with production of IFN-γ affects human papillomavirus susceptibility in rural women from Luohe, Henan, China.

PURPOSE: In this paper, the association between polymorphisms of IFN-γ +874T/A (rs2430561), IFN-γR1 -56 T/C (rs2234711), IFN-γR1 +95 C/T (rs7749390), and IFN-γR1 -611A/G (rs 1327474) and human papillomavirus (HPV) susceptibility was investigated in rural women from Luohe, Henan, China. PATIENTS AND METHODS: A total of 520 rural women were enrolled from Luohe, including 260 with HPV infection and mild dysplasia or less and 260 without HPV infection. Single-nucleotide polymorphisms (SNPs) of IFN-γ +874T/A, IFN-γR1 -56 T/C, IFN-γR1 +95 C/T and IFN-γR1 -611A/G were genotyped using TaqMan Pre-Designed SNP Genotyping Assays. Serum IFN-γ levels were measured using Human IFN-γ Quantikine ELISA Kit. Multivariate logistic regression analysis was performed to identify the SNPs associated with HPV susceptibility. Serum IFN-γ levels were compared between different genotypes. RESULTS: The polymorphism of IFN-γ +874T/A was associated with HPV susceptibility and +874A carriers had an increased risk. Moreover, the odds ratio was higher in +874 AA carriers than in +874 AT carriers (1.672 vs 2.874). Serum IFN-γ levels were highest in IFN-γ +874 TT carriers, intermediate in AT carriers, and lowest in AA carriers (2.86±1.14 vs 1.57±0.79 vs 0.41±0.22 pg/mL, all P<0.05). CONCLUSION: The polymorphism of IFN-γ +874T/A was associated with HPV susceptibility in rural women from Luohe, Henan, China, and +874A carriers had an increased risk. The possible mechanism was that +874A carriers had a low production of IFN-γ.

[Spatial and Temporal Distribution Characteristics of Different Forms of Phosphorus in Three Sorts of Rivers around Lake Taihu].

Different forms of phosphorus from the upper reaches of river to lower reaches of river in nine rivers were analyzed to clarify the pollution characteristics of industrial effluent, agriculture effluent and sanitary wastewater to Lake Taihu in February (low water period), May (average water period) and August (abundant water period) of 2009. The results showed that total phosphorus (TP) dissolved total phosphorus (DTP) and soluble reactive phosphorus ( SRP) mass concentration all showed decreasing trend while enzymatic phosphorus (EHP) mass concentration increased with the increase of algal biomass from low water period to abundant water period. Mass concentrations of several forms of phosphorus were all the highest in the rivers impacted by sanitary wastewater, but sanitary wastewater's self-purification capabity from the upper reaches of river to lower reaches of river was the best, and the pollution to Lake Taihu was the lowest. Pollution from rivers impacted by industrial effluent was the highest. Mass concentration of EHP was higher than that of SRP in most cases, so EHP played an important role in Cyanbacterial harmful algal blooms events in Lake Taihu.

[Effect of Natural Organic Matter and Electrolytes on the Aggregation of C60 Nanoparticles in Aquatic Systems].

The ettect of natural organic matter (NOM) and electrolytes on the aggregation of G60 nanoparticles in aquatic systems was studied by using dynamic light scattering. The results showed that the concentration of C60 stable suspension prepared by toluene solvent-exchange method was about 20 mg x L(-1). The C60 nanoparticles in the suspension showed a high zeta potential and particle diameter was around 120 nm. Addition of simple electrolytes induced aggregation of C60 nanoparticles through acompressing electric double layer, which was consistent with the classic Derjaguin-Landau-Verwey-Overbeek (DLVO) theory of colloidal stability. The critical coagulation concentration (CCC) values of MgCl2 and CaCl2 were 9.6 and 6.7 mmol x L(-1). In presence of humic acid, the addition of NaCl and MgCl2 reduced the attachment efficiency and aggregation rate of C60 and increased CCCs. Humic acid enhanced the stability of C60 in water due to steric repulsion. However, the complexation reaction between Ca2+ and humic acid caused adsorption bridging with C60, which increased the aggregation rate and led to enhanced aggregation. This was identified as the primary mechanism of such enhanced aggregation behaviour. The aggregation and dispersion of C60 in water was influenced by the characteristics of organic matters, electrolyte species and other complex factors.

[Effect of recombinant human erythropoietin on hippocampal p-Akt and caspase-9 expressions in rats with status epilepticus and the mechanism].

OBJECTIVE: To observe the effect of recombinant human erythropoietin (rhuEPO) on p-Akt and caspase-9 expressions in the hippocampus of rats with status epilepticus (SE) and explore the neuroprotective mechanism of rhuEPO. METHODS: Adult male SD rats were randomized into control, PTZ, rHuEPO, LY294002 group, and DMSO groups and treated with normal saline (NS), PTZ, PTZ+rHuEPO, PTZ+LY294002+rHuEPO, and PTZ+DMSO+rHuEPO, respectively. The behavioral and electroencephalogram (EEG) changes of the rats were recorded, and the expressions of p-Akt and caspase-9 were detected using immunohistochemistry. The hippocampal expression of caspase-9 mRNA was detected using RT-PCR, and the expressions of Akt and p-Akt proteins were determined with Western blotting. RESULTS: The p-Akt-positive cell and p-Akt protein expression increased significantly while the caspase-9-positive cell and caspase-9 mRNA expression decreased in rHuEPO group as compared with those in PTZ group (P<0.05). LY294002 treatment prior to rHuEPO injection significantly abolished the effects of rHuEPO on caspase-9 and p-Akt immunohistochemical positivity and caspase-9 mRNA and p-Akt protein expressions (P<0.05). CONCLUSION: Administration of rHuEPO activates the PI3K/Akt signaling pathway in SE rats and increases the expression of p-Akt protein to regulate the expression of caspase-9, a regulatory factor of the mitochondrial-dependent apoptotic pathway, and therefore provides anti-apoptotic and neuroprotective effects.