• Bojesen Meyers posted an update 24 days ago

    The application of hydrogen peroxide (H2O2) to control harmful algal blooms is affected by algal density and species. In the present study, a simulation field study was carried out to evaluate the removal of cyanobacteria with high algal density (chlorophyll a of approximately 220-250 μg/L) and low algal density (chlorophyll a of approximately 30-50 μg/L) using 10, 20 mg/L H2O2 and 5 mg/L H2O2. The dynamics of algal biomass, nutrients, microcystins, phytoplankton, and zooplankton were measured within 7 d. The results showed that 5 mg/L H2O2 effectively eliminated algal biomass (measured as chlorophyll a and phycocyanin) and inhibited 50% of the photosynthetic activity of the cyanobacteria at 7 d in the low algal cell density group, while the same inhibition rate was observed in the high algal cell density group when the H2O2 was 20 mg/L. However, using a high dosage of H2O2, such as 10 mg/L, to suppress cyanobacteria with high biomass could result in a dramatic increase in nutrients and microcystins in the water column. The portion of eukaryotic algae, such as Chlorophyta, Bacillariophyta and Euglenophyta, in the phytoplankton community increased with increasing H2O2 concentrations; moreover, the dominant species of cyanobacteria changed from the nontoxic genus Dactylococcopsis to the toxic genus Oscillatoria, which may result in acute toxicity to zooplankton. Our results demonstrated that the application of H2O2 to control cyanobacterial blooms at the early stage when algal cell density was low posed less potential ecological risks and may have increased the diversity of the phytoplankton community.Volatile organic compounds (VOCs) has consistently been linked to ozone (O3) and secondary organic aerosol (SOA) formation, and ongoing emission policies are primarily focusing on total VOCs without addressing the association between regulation measures and secondary pollution characteristic. For enhancing VOCs emission policy, we investigated potential formation of O3 and SOA based on analyses of node-specific VOCs concentration and species distribution in solvent-consuming industry. Although aromatics were found to contribute most to O3 and SOA formation averagely (2.57 ± 2.14 g O3/g VOCs, 1.91 ± 1.67 g SOA/g VOCs), however, large disparity concerning emission and secondary pollution profile were identified among different emission nodes which demonstrated that regulation policy should be formulated based on comprehensive pollution characteristic. Therefore, emission nodes were classified into four clusters through data normalization, formatting and classification process, including aromatics dominated (7 emission nodes), aromatics-alkene dominated (4 emission nodes), aromatics-alcohols dominated (4 emission nodes) and alcohols dominated (4 emission nodes). And different dominating VOCs species were further obtained in each cluster. Proteasome purification Subsequently, focusing regulation measures of reducing O3 and SOA for different emission source clusters were proposed to guide pollution prevention and enhance future VOCs emission policies.Thallium (Tl) is a highly toxic metalloid and is considered a priority pollutant by the US Environmental Protection Agency (EPA). Currently, few studies have investigated the distribution patterns of bacterial and fungal microbiomes in Tl-impacted environments. In this study, we used high-throughput sequencing to assess the bacterial and fungal profiles along a gradient of Tl contents in Tl mine waste rocks in southwestern China. Our results showed that Tl had an important, but different influence on the bacterial and fungal diversity indices. Using linear regression analysis, we furtherly divided the dominant bacterial and fungal groups into three distinct microbial sub-communities thriving at high, moderate, and low levels of Tl. Furthermore, our results also showed that Tl is also an important environmental variable that regulates the distribution patterns of ecological clusters and indicator genera. Interestingly, the microbial groups enriched in the samples with high Tl levels were mainly involved in metal and nutrient cycling. Taken together, our results have provided useful information about the responses of bacterial and fungal groups to Tl contamination.PM2.5 pollution was associated with numerous adverse health effects. However, PM2.5 induced toxic effects and the relationships with toxic components remain largely unknown. To evaluate the metabolic toxicity of PM2.5 at environmentally relevant doses, investigate the seasonal variation of PM2.5 induced toxicity and the relationship with toxic components, a combination of general pathophysiological tests and metabolomics analysis was conducted in this study to explore the response of SD rats to PM2.5 exposure. The result of general toxicology analysis revealed unconspicuous toxicity of PM2.5 under environmental dose, but winter PM2.5 at high dose caused severe histopathological damage to lung. Metabolomic analysis highlighted significant metabolic disorder induced by PM2.5 even at environmentally relevant doses. Lipid metabolism and GSH metabolism were primarily influenced by PM2.5 exposure due to the high levels of heavy metals. In addition, high levels of organic compounds such as PAHs, PCBs and PCDD/Fs in winter PM2.5 bring multiple overlaps on the toxic pathways, resulting in larger pulmonary toxicity and metabolic toxicity in rats than summer.

    Recently there has been increasing interest in the use of regional anesthesia for minimally-invasive transforaminal lumbar interbody fusion (TLIF) and laminectomy, with the goal of reducing the side effects and risks associated with general anesthesia and also to improve patient satisfaction. The goal of this technical note is to describe important perioperative aspects to safely perform an awake spine surgery and to describe a novel technique to preform minimally-invasive TLIF using a pedicle-based retraction system.

    We report our patient selection criteria, perioperative anesthesia protocol and surgical technique for awake TLIF with the Maximum Access Surgery (MAS) TLIF Retraction System. We describe an illustrative case of a 66-year-old female that presented with leg pain, lumbar MRI revealed a grade one spondylolisthesis at L4-5 with severe canal stenosis. She underwent a L4-5 Awake MIS TLIF using the MAS TLIF Retraction System.

    The first 10 awake TLIF we performed with the MAS TLIF Retraction System had a mean procedure time of 117.

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