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Hot dry rock (HDR) geothermal energy has many advantages, such as being renewable, clean, widely distributed, and without time and weather limitations. Hydraulic fracturing is usually needed for the exploitation of HDR geothermal energy. It has many hidden faults in the reservoir/caprock sequences. Injecting fluid into underground formations during hydraulic fracturing often induces fault slip and leads to earthquakes. Therefore, to well understand the induced fault slip and earthquakes is important for the applications and development of HDR geothermal exploitation. In this study, we investigated the hazardous injection area of the induced earthquakes during hydraulic fracturing. The study was based on a hydraulic fracturing test in Qiabuqia geothermal field in China. According to the field, a fault-surrounding rock-fracturing region system was developed to study the influences of fluid injection on the stability of the specific fault. A total of 60 hydraulic fracturing regions and 180 numerical experiments were designed. The results revealed that the hazardous injection regions that threaten the fault's stability were near to the fault and concentrated on the following four areas: (a) above the top of the fault in underlying strata; (b) above the top of the hanging wall of the fault in underlying strata; (c) near to the fault planes in both footwall and hanging wall; (d) at the bottom of the footwall of the fault in underlying strata. The hazardous injection area can be controlled effectively by adjusting the injection pressure. [ABSTRACT FROM AUTHOR]

Hot dry rock (HDR) geothermal energy has become promising resources for relieving the energy crisis and global warming. The exploitation of HDR geothermal energy usually needs an enhanced geothermal system (EGS) with artificial fracture networks by hydraulic fracturing. Fault reactivation and seismicity induced by hydraulic fracturing raise a great challenge. In this paper, we investigated the characteristics of fault slip and seismicity by numerical simulation. The study was based on a hydraulic fracturing project in the geothermal field of Yishu fault zone in China. It revealed that fluid injection during hydraulic fracturing can cause the faults that exist beyond the fluid-pressurized region to slip and can even induce large seismic event. It was easier to cause felt earthquakes when hydraulic fracturing was carried out in different layers simultaneously. We also examined the effects of the location, permeability, and area of the fracturing region on fault slip and magnitude of the resulting events. The results of the study can provide some useful references for establishing HDR EGS in Yishu fault zone. [ABSTRACT FROM AUTHOR]

Pyrethroids are increasingly receiving attention as aqueous micropollutants, but their presence has been reported only in a few small coastal areas. In this study, we investigated the distribution, sources, and risks of nine pyrethroids in large marine zones. The 40 seawater samples were collected from the South Yellow Sea (SYS) and East China Sea (ECS) in China, during the spring of 2020, using a high-volume, solid-phase extraction method. The total pyrethroid concentrations ranged from 0.72 to 1.82 ng L−1 in the SYS and from 0.02 to 11.0 ng L−1 in the ECS. We used cluster analysis to classify pollutant sources into five categories, and discussed the influence of sources on the transport and distribution of pyrethroids in each group. Ecological risk assessment indicated that pyrethroids pose a high risk to crustaceans and a negligible risk to others. These results are important for understanding the behavior of pyrethroids in marine environments. [Display omitted] • Efficient Hi-throat/Hi-volume SPE was used to concentrate pyrethroids from seawater. • Occurrence of nine pyrethroids was investigated at South Yellow and East China Seas. • Distribution and sources are influenced by both human activities and ocean currents. • Ecological risk assessment indicated that pyrethroids pose a high risk to crustaceans. [ABSTRACT FROM AUTHOR]

Designing efficient policies to mitigate the transport GHG emissions is pivotal to tackle climate change. Fuel economy standards with incentives for electric vehicles have been widely adopted in road transport to curb vehicle tailpipe emissions and encourage fleet technology transition. Using a fleet-based life cycle model for the passenger vehicle sector in China, we show that solely relying on tailpipe-based standards will not suffice to meet the sectoral goal of peaking its GHG emissions by 2030. Switching to a well-to-wheels based standard, in conjunction with complementary policy instruments to regulate the vehicle embedded emissions and low carbon fuel production, could effectively close the mitigation gap and achieve holistic GHG emissions reduction. Incorporating such life cycle assessment approaches into the regulatory framework should occur as soon as practicable to provide sufficient GHG emissions reduction so that the transport sector can contribute to the overall economy-wide carbon reduction commitment. [ABSTRACT FROM AUTHOR]

Background: The efficacy and safety of dabigatran etexilate for Chinese patients with cerebral venous thrombosis (CVT) has not been well established., Methods: CHOICE-CVT was an exploratory, single-center, randomized, open-label study in the National Center for Neurological Disorders involving Chinese patients with CVT aged 18 to 80 years who were randomly assigned (1:1) to either dabigatran etexilate or warfarin. Oral anticoagulants were initiated after 10-15 days of LMWH. The primary efficacy and safety endpoints included the number of patients with recurrent CVT and/or deep venous thrombosis (DVT) and major clinical bleeding within 180 days. Secondary efficacy endpoints included venous recanalization and change in papilledema at day 180. Secondary safety outcomes comprised death, clinical nonmajor bleeding, and any bleeding. The study was registered with ClinicalTrials.gov under NCT03930940., Results: Between October 2017 and February 2023, a total of 89 patients were enrolled and randomly assigned to receive either dabigatran etexilate (n = 44) or warfarin (n = 45). At day 180, the dabigatran etexilate group showed a statistically nonsignificant but likely clinically significant number of patients with recurrent CVT and/or DVT (8 (18.2%; 95% CI, 6.3-30.0) vs 3 (6.7%; 95% CI, 0.0-14.2), p = 0.099, with a power (1-β) of 38.401%) compared with the warfarin group. The dabigatran etexilate group showed a comparable number of patients with clinical major bleeding (0 (0) vs 0 (0) p = 1.000), and clinical nonmajor bleeding (1 (2.3%; 95% CI, 0.0-6.9) vs 1 (2.2%; 95% CI, 0.0-6.7)) but demonstrated a lower risk of any bleeding (1 (2.3%; 95% CI, 0.0-6.9) vs 9 (20.0%; 95% CI, 7.8-32.2)) compared with the warfarin group. Most patients in both groups achieved venous recanalization according to the Modified Qureshi scale (27 (75%; 95% CI, 60.1-89.9) in the dabigatran etexilate group vs 34 (82.9%; 95% CI, 70.9-95.0) in the warfarin group) and exhibited improvement in papilledema as per the Frisén classification (35 (97.2%; 95% CI, 91.6-100.0) in the dabigatran etexilate group vs 37 (88.1%, 95% CI, 77.9-98.3) in the warfarin group)., Conclusions: These findings regarding efficacy and safety support the consideration of dabigatran etexilate therapy as a viable treatment option for Chinese patients with CVT., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Organophosphate esters (OPEs) are widely distributed in surface water systems, but limited information was available on the spatial occurrence and ecological risks of OPEs in the Bohai Sea. In this study, 89 water samples in the Bohai Sea and the five surrounding rivers were investigated for the determination of 15 OPEs. The concentration of ∑ 15 OPEs ranged from 373.20 to 2931.27 ng·L -1 in the river water and 137.81 to 2641.30 ng·L -1 in the seawater, with high levels of OPEs in Liaodong Bay. Tris(2-chloroethyl) phosphate (TCEP, 10- 92 %) and triethyl phosphate (TEP, 5- 64 %) were dominant for OPEs. The correlation analysis, principal component analysis and hierarchical cluster analysis suggested the conjunction of municipal wastewater via river input and maritime shipping was the main source of OPEs in the Bohai Sea. The ecological risk assessment indicated that the individual OPEs arise low ecological risks in the Bohai Sea, while medium ecological risks of ∑ 15 OPEs are in minority river samples., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Graphene Oxide (GO) has wide applications in many fields which has caused a large expected quantity of the graphene-based wastes. It is necessary to understand the toxic effects of the GO on the activated sludge (AS) considering its inevitable discharge to the wastewater treatment plants as the ultimate repositories for these wastes. In this study, the acute exposures of the multilayer Nano-graphene oxide (MNGO) at different dosages were conducted in order to investigate its integrated effects on the formation of the biofilm, mature biofilm and the microbial activity of the activated sludge. Raman spectroscopy and laser scanning confocal microscopy (LSCM) were adopted for the in-situ characterization of the biofilm with the exposure of the MNGO. The results showed that the activated sludge was tolerable to the acute exposure of the less than 100 mg/L of the MNGO, especially for the mature biofilm, and only a subtle decrease was found in the size and thickness during the formation of the biofilm, while the amount of 300 mg/L of the MNGO caused the sever deterioration on the activated sludge system. The microbial metabolic activity, viability, and the biological removal of the nutrients were significantly affected with the more than 100 mg/L of the MNGO. It was also demonstrated by the microbial cytotoxicity tests that the increase in the exposure of the MNGO was related to the increase in the reactive oxygen species (ROS) and the damaging degree of the cell membrane., (Copyright © 2020 Elsevier Inc. All rights reserved.)