Distribution,characteristics and daily fluctuations of microplastics throughout wastewater treatment plants with mixed domestic-industrial influents in Wuxi City,China

In wastewater treatment plants(WWTPs),microplastics(MPs)are complex,especially with mixed domestic–industrial influents.Conventional random grab sampling can roughly depict the distribution and characteristics of MPs but can not accurately reflect their daily fluctuations.In this study,the concentration,shape,polymer type,size,and color of MPs were analyzed by micro-Raman spectroscopy(detection limit of 0.05 mm)throughout treatment stages of three mixed domestic–industrial WWTPs(W1,W2,and W3)in Wuxi City,China,and the daily fluctuations of MPs were also obtained by dense grab sampling within 24 h.For influent samples,the average MP concentration of 392.2 items/L in W1 with 10%industrial wastewater was much higher than those in W2(71.2 items/L with 10%industrial wastewater)and W3(38.3 items/L with 60%industrial wastewater).White polyethylene granules with a diameter less than 0.5 mm from plastic manufacturing were the most dominant MPs in the influent of W1,proving the key role of industrial sources in MPs pollution.In addition,the daily dense sampling results showed that MP concentration in W1 influent fluctuated widely between 29.1 items/L and 4617.6 items/L within a day.Finally,few MPs(less than 4.0 items/L)in these WWTPs effluents were attributed to the effective removal of wastewater treatment processes.Thus,further attention should be paid to regulating the primary sources of MPs.

Monitoring of Sleep Indicators, Physical Activity, Pain, and Fatigue in Patients with Systemic Lupus Erythematosus and Relations among These Variables: A Pilot Study

Background: Poor sleep, fatigue, and pain are major health problems in patients with systemic lupus erythematosus (SLE). However, only cross-sectional surveys on these health outcomes have been conducted, and the association between day-to-day fluctuations remains unknown. Objectives: We aimed to characterize daily fluctuations in sleep quality, physical activity, pain, and fatigue in patients with SLE. Method: Exploratory study with a cross-sectional design. Two rheumatology centers (a university hospital and a prefectural hospital) in Japan between September 2017 and May 2019. The sample size was set to 20. Demographic and clinical data were collected. Sleep and physical activity were measured with monitoring devices;pain and fatigue levels were recorded daily during the 4-week period. The Pittsburgh Sleep Quality Index, Short Form Health Survey-12, the Japanese version of the Lupus Patient Outcome, and SLE Disease Activity Index 2000 were collected at the start and end of the study. Descriptive statistics and coefficients of variation (CV) were tabulated to examine daily fluctuations. Pearson correlation coefficients were obtained for monitored variables. Results: The mean age was 43.7 ± 8.5 years, and the mean SLE duration was 16.0 ± 7.2 years. The mean moderate-to-vigorous physical activity (MVPA) duration was 7.8 ± 5.8 min/day, and the mean total sleep duration was 391.8 ± 65.3 min, with a mean sleep efficiency of 88.6% ± 6.1%. Daily fluctuations were high for leaving the bed frequency, MVPA duration, pain, and waking after sleep onset. Seventeen participants showed correlations between some of the variables, such as fatigue or longer MVPA duration and poorer sleep outcomes;longer sleep latency and increased frequency of leaving the bed;and higher physical activity and increased pain and fatigue. Conclusion: The quality of sleep and fatigue fluctuated daily, and correlations existed between these variables, as well as for pain and physical activity. The impact of MVPA duration on pain and fatigue is of concern as increased physical activity may worsen the quality of life patients with SLE. The monitoring of sleep and physical activity using the device seems feasible for SLE symptom management.

Effect of daily salinity fluctuation on the intraspecific interactions of a euhalophyte(Suaeda salsa)along a salinity gradient

Heterogeneity of soil salinity is a prominent environmental characteristic in the intertidal zone of estuaries,affecting the plant growth and the shift of biotic interactions in the salt marsh.This study aims to examine the interactive effects of a salinity gradient and salinity fluctuations on intraspecific interactions of a euhalophyte.We assessed the impact of daily fluctuating salinity on the outcome of intraspecific interactions by cultivating seeds of Suaeda salsa(Chenopodiaceae)in river sand.The experiment was conducted in a greenhouse with three treatments:daily salinity fluctuations(static and fluctuating salinity),a salinity gradient(200 and 400 mmol L^(−1))and three planting densities(1,2 and 4 plants/pot).First,height and biomass of plants were measured at both the start and end of the experiment.Then,the growth indexes and log response ratio of S.salsa were analyzed.The outcome of intraspecific interactions of S.salsa shifted from competition in low salinity to facilitation in high salinity,and high conspecific density strengthened the competition and facilitation intensities.Daily salinity fluctuation did not significantly affect the plant growth and the outcome of intraspecific interactions,but did have a significant influence on belowground biomass.Our results suggest that the stress-gradient hypothesis may apply to predicting the variation of the intraspecific relationship of a salt-tolerant species along a salinity gradient,and the magnitude of this variation is density dependent.These findings help us understand how individuals and populations of a euhalophyte species respond to the natural variation or human modification of salinity conditions.

On China’s Exchange Rate Flexibility and Stability: The More Flexible against the U.S. Dollar, the More Stable in Effective Terms

The Chinese authorities have often emphasized the importance of maintaining the renminbi＇s stable exchange rate without stating explicitly how this stability should be measured. This paper argues that the relevant concept for this stability should be in terms of the rnminbi＇s effective exchange rate, rather than its rate against any particular currency, such as the U. S. dollar. Under the current circumstances where key currencies＇ exchange rates fluctuate freely, if the authorities wish to maintain the stability of the renmnibi＇s effective exchange rate, they would want to let the renminbi＇s exchange rate fluctuate much more against the U. S. dollar than in the past because such fluctuations would greatly reduce the magnitude of the renminbi＇s fluctuations against other key currencies and thus its effective exchange rate. This point has been demonstrated by illustrative figures and by comparing the renminbi＇s hypothetical, greater exchange rate fluctuations with its actual fluctuations.