Residue analysis, dissipation patterns of chlorfenapyr, diafenthiuron and their corresponding metabolites in tea trees, and dietary intake risk assessment.

BACKGROUND: Recently, chlorfenapyr and diafenthiuron have been widely used to prevent and control diseases and pests in tea production. However, rare studies have investigated the dissipation patterns of chlorfenapyr, diafenthiuron and their metabolites simultaneously in tea matrices. Here, we established an analytical method to investigate the degradation patterns of five target compounds in tea shoots and made tea samples. Moreover, the dietary intake risk assessment of chlorfenapyr-diafenthiuron mixture among Chinese populations was evaluated based on the supervised field experiment. RESULTS: The mean recoveries of the primary analytes at five spiking levels were between 95.6% and 112.6% in tea shoots and made tea, respectively, and the values of RSD (relative standard deviation) were lower than 9.7% for all the target analytes. The field trial results showed that the half-lives of chlorfenapyr and diafenthiuron based on the residue definition were 10.0-12.4 days and 4.3-5.9 days, respectively, in tea shoots. For the dietary intake risk assessment, the risk quotient (RQ) values in made tea ranged from 30.4% to 73.9% at the pre-harvest interval of 14 days, which were significantly less than 100%. CONCLUSION: The accuracy and precision of the developed method were satisfied by the measurement requirements according to the validation results. The dynamic dissipation experiments suggested that diafenthiuron was much easier to dissipate than chlorfenapyr. Moreover, the existence of tralopyril made the half-life of chlorfenapyr significantly increase, indicating that practical application of chlorfenapyr should take careful consideration of its metabolite. Finally, the potential chronic dietary risks of the chlorfenapyr-diafenthiuron mixture to human communities were within the acceptable range. © 2022 Society of Chemical Industry.

Clinical assessment of endovenous thermal ablation combined with concomitant phlebectomy for the treatment of lower limb varicose veins with or without poor glycemic control.

BACKGROUND: This study aimed to investigate the clinical results of endovenous thermal ablation combined with stab phlebectomy for unilateral varicose veins based on diabetic management. METHODS: The study reviewed 501 patients who underwent endovenous thermal ablation combined with stab phlebectomy for unilateral varicose veins, including 337 nondiabetics (control group) and 164 diabetics. Diabetics with hemoglobin A1c ≥7% were classified as the poor glycemic control group, and hemoglobin A1c <7% as the good glycemic control group. Surgical outcomes were assessed by Venous Clinical Severity Score. The Chronic Venous disease quality of life Questionnaire was used to assess the quality of life. RESULTS: Lower limb varicose veins can be treated successfully with endovenous thermal ablation combined with stab phlebectomy in patients with or without poor glycemic control, accompanied by a significant improvement in health status. For patients with initial varicose veins (preoperative Venous Clinical Severity Score <10), the results revealed satisfactory improvements in Venous Clinical Severity Score and quality of life among the control, poor glycemic control, and good glycemic control groups. Patients with advanced varicose veins (preoperative Venous Clinical Severity Score ≥10) also showed an obvious amelioration concerning venous symptoms and quality of life. However, the extent of improvement varied among the 3 groups. Patients subjected to advanced varicose veins with the condition of poor glycemic control exhibited a less desirable improvement in postoperative health conditions compared with the control and good glycemic control groups, especially in edema relief and ulcer healing. CONCLUSION: Endovenous thermal ablation combined with stab phlebectomy is safe and effective in the treatment of varicose veins with or without poor glycemic control. Clinical attempts at hemoglobin A1c management may contribute to improved clinical outcomes in patients with advanced varicose veins.

A life cycle assessment of hard carbon anodes for sodium-ion batteries.

Waste management is one of the biggest environmental challenges worldwide. Biomass-derived hard carbons, which can be applied to rechargeable batteries, can contribute to mitigating environmental changes by enabling the use of renewable energy. This study has carried out a comparative environmental assessment of sustainable hard carbons, produced from System A (hydrothermal carbonization (HTC) followed by pyrolysis) and System B (direct pyrolysis) with different carbon yields, as anodes in sodium-ion batteries (SIBs). We have also analysed different scenarios to save energy in our processes and compared the biomass-derived hard carbons with commercial graphite used in lithium-ion batteries. The life cycle assessment results show that the two systems display significant savings in terms of their global warming potential impact (A1: -30%; B1: -21%), followed by human toxicity potential, photochemical oxidants creation potential, acidification potential and eutrophication potential (both over -90%). Possessing the best electrochemical performance for SIBs among our prepared hard carbons, the HTC-based method is more stable in both environmental and electrochemical aspects than the direct pyrolysis method. Such results help a comprehensive understanding of sustainable hard carbons used in SIBs and show an environmental potential to the practical technologies. This article is part of the theme issue 'Bio-derived and bioinspired sustainable advanced materials for emerging technologies (part 2)'.

Residual behavior and dietary intake risk assessment of flonicamid, dinotefuran and its metabolites on peach trees.

BACKGROUND: Flonicamid and dinotefuran are widely applied to control pests and diseases in various economic crops arousing much public concerns about the potential risk to human health. In this study, the multi-determination and residual behavior of flonicamid-dinotefuran mixture on peach trees were investigated. The chronic risk of long-term dietary intake for Chinese consumers was evaluated. RESULTS: An optimized QuEChERS method combined with ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis for simultaneous determination of flonicamid, dinotefuran and its metabolites was established to analyze the residual dissipation and terminal residues in peach matrices. The results demonstrated that (i) a satisfactory linearity relationship with the detector response and the correlation coefficient R2 > 0.999, the average recoveries of these four analytes ranged from 94 to 108%, the relative standard deviation was between 1.0% and 8.8%, and the limit of the quantitation was 0.02 mg kg-1 ; (ii) the dissipation behaviors of flonicamid and dinotefuran followed with the first-order dynamic kinetics model, and the half-lives were 6.9-12.4 days and 8.1-15.1 days, respectively; (iii) the recommended preharvest interval (PHI) was 21 days, the risk quotient (RQ) values of flonicamid and dinotefuran were 16.6 and 20.7%, respectively, which were significantly less than 100%. CONCLUSION: The established analytical method met the detection requirement in terms of sensitivity, accuracy, and precision. Additionally, the results indicated that the potential dietary intake risk of the flonicamid-dinotefuran mixture on peach trees was negligible. This work can be utilized in the safe and responsible use of flonicamid-dinotefuran mixture and provide guidance for establishing its maximum residue limit (MRL) in China. © 2021 Society of Chemical Industry.

Risk Assessment of Infrastructure System of Systems with Precursor Analysis.

Physical infrastructure systems are commonly composed of interconnected and interdependent subsystems, which in their essence constitute system of systems (S-o-S). System owners and policy researchers need tools to foresee potential emergent forced changes and to understand their impact so that effective risk management strategies can be developed. We develop a systemic framework for precursor analysis to support the design of an effective and efficient precursor monitoring and decision support system with the ability to (i) identify and prioritize indicators of evolving risks of system failure; and (ii) evaluate uncertainties in precursor analysis to support informed and rational decision making. This integrated precursor analysis framework is comprised of three processes: precursor identification, prioritization, and evaluation. We use an example of a highway bridge S-o-S to demonstrate the theories and methodologies of the framework. Bridge maintenance processes involve many interconnected and interdependent functional subsystems and decision-making entities and bridge failure can have broad social and economic consequences. The precursor analysis framework, which constitutes an essential part of risk analysis, examines the impact of various bridge inspection and maintenance scenarios. It enables policy researchers and analysts who are seeking a risk perspective on bridge infrastructure in a policy setting to develop more risk informed policies and create guidelines to efficiently allocate limited risk management resources and mitigate severe consequences resulting from bridge failures.