【目的】城市公园树木的碳(C)计量和管理是城市减少CO2排放的有效策略之一,树木冠层覆盖(Urban tree canopy,UTC)信息在树木生物量和C储存量的计量中具有一定潜力,旨在初步估算广州市典型城市公园基于UTC和叶面积的碳存储和碳固定量的...【目的】城市公园树木的碳(C)计量和管理是城市减少CO2排放的有效策略之一,树木冠层覆盖(Urban tree canopy,UTC)信息在树木生物量和C储存量的计量中具有一定潜力,旨在初步估算广州市典型城市公园基于UTC和叶面积的碳存储和碳固定量的转换系数及适用性。【方法】基于城市树木碳输入生态过程,对城市绿地系统树木冠层覆盖与其C存储和C固定功能的计量方法进行探索,建立了基于广州城市公园树木冠层覆盖和叶面积参数指标的C存储和C固定转换系数,依此估算广州市4个典型城市公园C存储和C固定量。【结果】广州市城市公园基于UTC的C存储转换系数为92.215±12.836 t·hm-2,C固定量转换系数为5.606±2.19 t·hm-2a-1;基于叶面积总量的C存储转换系数为24.17±7.12 t·hm-2,C固定量转换系数为2.59±0.5 t·hm-2a-1。基于叶面积总量转换系数估算的C存储量和C固定量比基于面积尺度转换系数估算的分别要小0.4%和3.3%,比基于UTC面积估算的碳存储量高13.8%,而碳固定量要低3.15%。【结论】基于UTC的C存储和C固定量的计量方法仅对城市树木覆盖区域进行估算,完全剔除了城市公园中其他复杂的下垫面类型,该计量方法其结果相对精准。基于树木叶面积的C存储和C固定量估算既考虑了树木冠层覆盖的面积,也考虑了冠层结构指标(叶面积指数),充分考虑了植物C输入过程的各个影响因素,其计量结果相对较低,但具有更高的精度。展开更多
In the face of the elevated incidence and mortality rate of septic shock in the ICU,this retrospective study seeks to investigate the indicative and predictive value of high-mobility group box 1(HMGB1)and miR-146b in ...In the face of the elevated incidence and mortality rate of septic shock in the ICU,this retrospective study seeks to investigate the indicative and predictive value of high-mobility group box 1(HMGB1)and miR-146b in patients with septic shock.Quantitative RTPCR was employed in this study to quantify the HMGB1 and miR-146b levels in plasma samples obtained from the patient group and healthy controls.The investigation involved the comparison between the two groups and tracking changes in the patient group over time.The finding revealed that upon admission,the patient group exhibited markedly elevated relative expression levels of HMGB1,which subsequently decreased over time.Conversely,the patient group displayed significantly reduced relative expression levels of miR-146b upon admission,which subsequently increased over time compared to the control group.Receiver operating characteristic(ROC)curves showed good predictive value for HMGB1 and miR-146b.The experimental results suggest that HMGB1 and miR-146b serve as valuable and convenient biomarkers for evaluating the severity of septic shock and predicting mortality.Additionally,it is proposed that serum miR-146b may be inducible and potentially exerts a negative regulatory effect on the expression of HMGB1.展开更多
基金Supported by the Natural Science Foundation of Hubei Province(2021CFB026)Scientific Research Project of Hubei Pathophysiological Society(2021HBAP002)+2 种基金Medical Service Capacity Building and Health Personnel Training Project of the Central Government(New Finance Society[2022]No.255)Key Project of Science and Technology Program of Nanshan District,Shenzhen(NS2022014)Wu Jieping Medical Foundation Clinical Research Project(320.6750.2021-11-12)。
文摘In the face of the elevated incidence and mortality rate of septic shock in the ICU,this retrospective study seeks to investigate the indicative and predictive value of high-mobility group box 1(HMGB1)and miR-146b in patients with septic shock.Quantitative RTPCR was employed in this study to quantify the HMGB1 and miR-146b levels in plasma samples obtained from the patient group and healthy controls.The investigation involved the comparison between the two groups and tracking changes in the patient group over time.The finding revealed that upon admission,the patient group exhibited markedly elevated relative expression levels of HMGB1,which subsequently decreased over time.Conversely,the patient group displayed significantly reduced relative expression levels of miR-146b upon admission,which subsequently increased over time compared to the control group.Receiver operating characteristic(ROC)curves showed good predictive value for HMGB1 and miR-146b.The experimental results suggest that HMGB1 and miR-146b serve as valuable and convenient biomarkers for evaluating the severity of septic shock and predicting mortality.Additionally,it is proposed that serum miR-146b may be inducible and potentially exerts a negative regulatory effect on the expression of HMGB1.
