Photosynthetic Characteristics of Smaller and Larger Cell Size-Fractioned Phytoplankton Assemblies in the Daya Bay, Northern South China Sea

Cell size of phytoplankton is known to influence their physiologies and, consequently, marine primary production. To characterize the cell size-dependent photophysiology of phytoplankton, we comparably explored the photosynthetic characteristics of piconano- (<20 µm) and micro-phytoplankton cell assemblies (>20 µm) in the Daya Bay, northern South China Sea, using a 36-h in situ high-temporal-resolution experiment. During the experimental periods, the phytoplankton biomass (Chl a) in the surface water ranged from 0.92 to 5.13 μg L−1, which was lower than that in bottom layer (i.e., 1.83–6.84 μg L−1). Piconano-Chl a accounted for 72% (mean value) of the total Chl a, with no significant difference between the surface and bottom layers. The maximum photochemical quantum yield (FV/FM) of Photosystem II (PS II) and functional absorption cross-section of PS II photochemistry (σPS II) of both piconano- and micro-cells assemblies varied inversely with solar radiation, but this occurred to a lesser extent in the former than in the latter ones. The σPS II of piconano- and micro-cell assemblies showed a similar change pattern to the FV/FM in daytime, but not in nighttime. Moreover, the fluorescence light curve (FLC)-derived light utilization efficiency (α) displayed the same daily change pattern as the FV/FM, and the saturation irradiance (EK) and maximal rETR (rETRmax) mirrored the change in the solar radiation. The FV/FM and σPS II of the piconano-cells were higher than their micro-counterparts under high solar light; while the EK and rETRmax were lower, no matter in what light regimes. In addition, our results indicate that the FV/FM of the micro-cell assembly varied quicker in regard to Chl a change than that of the piconano-cell assembly, indicating the larger phytoplankton cells are more suitable to grow than the smaller ones in the Daya Bay through timely modulating the PS II activity.

Exploring the Quantity Change Pattern of Environment-Friendly Products in the Sharing Economy

In the practice of various Internet-based sharing economies, environmental issues of shared products become more prominent and urgent. By analysing the relationship among government, enterprises, and consumers, this paper develops a system dynamics model based on the evolutionary game theory to explore the quantity change pattern of environment-friendly products in a sharing industry. A discrete dynamic system simulation of the quantity change process takes shared bikes in Beijing as a case study. The simulation results are consistent with the analysis of evolutionary game theory. The results show that government subsidies to both enterprises and consumers can lead to higher quantities of environment-friendly shared products, while consumer subsidy is better than enterprise subsidy. In addition, governments and enterprises need to ensure moderate investments to improve consumer experience and environmental awareness.

Assessing the Dynamics of Urban Growth and Land Use Changes in Jeli Using Geospatial Technique

Land use change pattern in Jeli is been given a focus as part of tool for land planning anddevelopment. An increasing of population in Jeli make this study is relevant to aid an understandingon land use changes in this area due to the demanded for development and rapid land utilisation.Land use change pattern can be obtained via geospatial technique by Geographical InformationSystem (GIS) together with satellite imagery analysis. In this study, land use maps produced fromsupervised classification using maximum likelihood algorithm give a high accuracy of 92.05%.From classified land use images, urban expansion index (SI) were then calculated from year 1984to 2012. Pearson’s correlation analysis discovered a strong negative correlation between forest andagricultural areas which reflected that with increased of agriculture area, forest reserve was founddepleted. The SI of Jeli showed a low to rapid growth in 1994 and 1997 to 2012 respectively. Thestudy reflected the progressive development in Jeli promotes sustainable usage of forest area wheneffort of reforestation was carried out forming a co-existence land use category between forest andagriculture.

Early Serum HBV RNA Level in Combination With the HBeAg Response Can Effectively Predict the HBeAg Response in Patients on Nucleos(t)ide Analogue Therapy (ClinicalTrials.gov (NCT03909191)

Background: Serum HBV RNA level has the potential to monitor antiviral therapy in patients with chronic hepatitis B. This study aimed to explore serum HBV RNA dynamic change pattern and its predict value on the efficacy of 96 weeks nucleos(t)ide analogue (NA) treatment in HBeAg-positive and HBeAg-negative patients with chronic hepatitis B (CHB).Methods: A real-life cohort study of 78 patients with CHB on NA treatment was conducted. Dynamic change patterns of serum HBV RNA and correlation with other HBV markers in the early treatment period of 96 weeks of NA treatment in patients with CHB were determined and compared. The performance of serum HBV RNA on treatment efficacy was analyzed by receiver operating characteristic (ROC) analyses. Results: HBeAg-positive and HBeAg-negative patients with CHB had similar viral change patterns during NA treatment. Serum HBV RNA level was consistently correlated with HBeAg and HBsAg titers in HBeAg-positive patients during NA treatment, but serum HBV RNA was only moderately correlated with serum HBV DNA level in HbeAg-negative patients before treatment. Serum HBV RNA decreased more rapidly in patients with the HBeAg seroconversion (SC) response than in patients without the HBeAg SC response; it had good early discriminatory ability for the HBeAg response with area under the ROC curve (AUROC) of 0.70 and 0.730 at 12 and 24 weeks of treatment, respectively. The cutoff value of serum HBV RNA of 4.31 log cps/mL in combination with the HBeAg decrease degree of 1.55 at 24 weeks of treatment had a good two-way predictive capability for the HBeAg response (PPV%: 83.33% and NPV%: 81.25%), and the specificity was 96.30%. Conclusion: Serum HBV RNA level had early discriminatory ability for the HBeAg response. Early HBeAg response can improve the discriminatory ability of serum HBV RNA.