Vazquezritter2795

A series of experiments for calcination and subsequent digestion to increase the grade of phosphate rock were performed. Fluorine and chlorine released by calcination and digestion were investigated. The forms of both elements were studied by sequential chemical extraction. The grades of raw and calcined phosphate rocks, and their phosphorus concentrates were confirmed according to the value of P2O5%. The results showed that fluorine and chlorine in phosphate rock mainly existed in carbonate-bound and residual forms. The grade of phosphate rock can be well increased by calcination and subsequent digestion. By digestion at the optimal condition of 2.51 for liquid-solid ratio, 60 °C for digestion temperature and 50 min for digestion time, the phosphorus concentrates digested from the calcined phosphate rock of 1000 °C reached the highest grade (P2O5% = 33.24%). By calcination, the released fluorine was mainly HF at a low temperature and SiF4 at a high temperature, with fluorine release amount of 1.61 × 104-3.82 × 104 g/t at 900-1100 °C. Cl2, HCl and Cl- were mainly released at 200-500 °C, less than 800 °C and more than 800 °C, which release amount were 9.40 × 10-2.54 × 102 g/t, 2.10 × 102-1.53 × 104 g/t and 2.24 × 102-5.61 × 102 g/t, respectively. By digestion with water for the calcined phosphate rock of 900-1100 °C, the concentrations of fluorine and chlorine in effluent were respectively 77.2-160 mg/L and 7.99-19.6 mg/L. It can be concluded that fluorine and chlorine released by calcination for phosphate rock contribute greatly to atmospheric acid rain and equipment corrosion; by digestion, the discharge of fluorine seriously exceeds the standard and may cause greater pollution to the water body.Strobilurin fungicides have been frequently detected in aquatic environments and can induce mitochondrial toxicity to non-target aquatic organisms. However, the derived toxicity and subsequent mechanisms related to their adverse effects are not fully elucidated. In the present study, we compared the mitochondrial and developmental toxicity of azoxystrobin, pyraclostrobin, and trifloxystrobin using zebrafish embryo/larvae. The results showed that all three strobilurins inhibited mitochondrial and non-mitochondrial respiration (the potency is pyraclostrobin ≈ trifloxystrobin > azoxystrobin). Behavioral changes indicated that sublethal doses of pyraclostrobin and azoxystrobin caused hyperactivity of zebrafish larvae in dark cycles, whereas trifloxystrobin resulted in hypoactivity of zebrafish larvae. In addition, pyraclostrobin exposure impaired the inflation of swim bladder, and caused down-regulation of annexin A5 (anxa5) mRNA levels, and up-regulated transcript levels of pre-B-cell leukemia homeobox 1a (pbx1a lethal doses and higher developmental toxicity at sublethal doses compared to the two other strobilurins tested. These results provide novel information for toxicological study as well as risk assessment of strobilurin fungicides.The reduction of NOx emissions in a VOC-limited region can lead to an increase of the local O3 concentration. An evaluation of the net health effects of such pollutant changes is therefore important to ascertain whether the emission control measures effectively improve the overall protection of public health. In this study, we use a short-term health risk (added health risk or AR) model developed for the multi-pollutant air quality health index (AQHI) in Hong Kong to examine the overall health impacts of these pollutant changes. BMS1166 We first investigate AR changes associated with NO2 and O3 changes, followed by those associated with changes in all four AQHI pollutants (NO2, O3, SO2, and particulate matter (PM)). Our results show that for the combined health effects of NO2 and O3 changes, there is a significant reduction in AR in urban areas with dense traffic, but no statistically significant changes in other less urbanized areas. The increase in estimated AR for higher O3 concentrations is offset by a decrease in the estimated AR for lower NO2 concentrations. In areas with dense traffic, the reduction in AR as a result of decreased NO2 is substantially larger than the increase in AR associated with increased O3. When additionally accounting for the change in ambient SO2 and PM, we found a statistically significant reduction in total AR everywhere in Hong Kong. Our results show that the emission control measures resulting in NO2, SO2, and PM reductions over the past decade have effectively reduced the AR over Hong Kong, even though these control measures may have partially contributed to an increase in O3 concentrations. Hence, efforts to reduce NOx, SO2, and PM should be continued.

The right choice of dressing after skin grafting, especially in the anatomically complex and aesthetically important head and neck area, is difficult. It is important to have a dressing which is durable and doesn't need a lot of dressing changes. This study introduces a novel, individually moulded silicon dressing; and investigates the number of dressing changes, durability of the dressing and the aesthetic outcome of patients receiving this new type of dressing, in comparison to a control group.

The present retrospective single center controlled case series study reports our experiences using two different types of dressing on patients undergoing full thickness skin grafts in the head during the period 01 May 2016 to 01 May 2020. Data were analysed according to the type of dressing with either a transparent moulded silicone dressing or an established silicone sheet dressing.

52 patients were included in the study. We found no difference in the aesthetic outcome and complication rate (p>0.05) between the two groups. The number of days until first dressing change after surgery, the number of dressing changes or follow up visits in the outpatient care until complete wound healing, and the overall number of dressing changes were all statistically significantly reduced (p<0.05).

Addition-cured silicone used as a moulded dressing in full thickness skin grafts has longer durability and leads to a significant reduction of dressing changes with equal aesthetic outcome compared to an establishes silicone sheet dressing.

Addition-cured silicone used as a moulded dressing in full thickness skin grafts has longer durability and leads to a significant reduction of dressing changes with equal aesthetic outcome compared to an establishes silicone sheet dressing.