By-production,emissions and abatement costeclimate benefit of HFC-23 in China's HCFC-22 plants

After the Kigali Amendment(KA)came into effect,HCFC-22 plants are obliged to limit HFC-23 emissions.Therefore,the study of costeffective mitigation pathways for HFC-23 is important for the sustainable implementation of KA in China and other HCFC-22 producing countries.This study constructed an inventory of HFC-23 by-production,emissions,and abatement for HCFC-22 plants in China from 2006 to 2020,and predicted the costs and climate benefits of HFC-23 abatement in China's compliance with the KA between 2021 and 2060.Results showed that HFC-23 emissions from HCFC-22 plants in China contributed about 60%of the growth in global atmospheric mole fraction of HFC-23 observed by Advanced Global Atmospheric Gases Experiment(AGAGE)from 2007 to 2020.Furthermore,China's cumulative HFC-23 abatement was about 109 kt(1613 Mt CO_(2)-eq)from 2006 to 2019,accounting for 53%of total by-production,which allowed the global atmospheric mole fraction and radiative forcing of HFC-23 in 2020 to avoid an uplift of 9.2×10^(-9)and i.7 mW m^(-2),respectively,contributing to climate change mitigation.Under the baseline of the Kigali Amendment,less emission(LE),and resource utilization(RU)scenarios,the cumulative HFC-23 abatement from 2021 to 2060 would be 683±29 kt(10,107±431 Mt CO_(2)-eq),694±29 kt(10,277±427 Mt CO_(2)-eq),and 702±29 kt(10,385±426 Mt CO_(2)-eq),respectively.The cumulative net abatement costs for the KA,LE,and RU scenarios would be(5.0±0.2)billion,(2.9±0.2)billion,and(-2.7±0.2)billion CNY(2021 prices),respectively.In the future,applying resource utilization technology to reduce HFC-23 emissions can achieve both climate and economic benefits.

源自前列腺基底细胞的前列腺部尿道再上皮化方式可能是2微米激光犬前列腺切除术后创面理想修复方式

本研究通过观察2微米激光犬前列腺切除术（two-micronlaser resection of the prostate，TmLRP）后前列腺部尿道创伤修复病理组织学改变，探讨前列腺部尿道创面再上皮化方式并评估该再上皮化方式的效果。选取15只成年健康雄性中华田园犬，分别行2微米激光前列腺汽化切除术及部分膀胱颈黏膜切除术，于术后3天、1、2、3及4周处死动物，留取前列腺部尿道及膀胱颈标本，苏木素伊红染色（Hematoxylin eosin，HE）染色光镜下观察创面再上皮化病理组织学改变，免疫组织化学染色检测前列腺部尿道创面细胞角蛋白14（Cytokeratin，CK14）、CK5、 CK18 , 突触素（Synaptophysin，Syn）、嗜铬素（Chromogranin A , CgA）、尿斑蛋白（uroplakin）、转化生长因子β1 （Transforming growth factor-β1, TGF-β1）和转化生长因子βII受体（Transforming growth factor-β type II receptor,TGF-βRI I）的表达，实时定量PCR方法检测前列腺部尿道创面CK14、CK5、CK18和Syn mRNA表达，Van Gieson染色分别检测前列腺部尿道和膀胱颈创面胶原纤维表达量。结果显示，前列腺部尿道由创面下残余前列腺上皮细胞增殖、迁移再分化完成再上皮化过程；创面下增殖的前列腺上皮细胞表达CK14，CK5，不表达CK18、Sy n和CgA，再生上皮术后3周开始表达uroplakin。增殖的前列腺细胞和再生上皮高表达TGF-β1和TGF-β RII，表达强度与创面修复再上皮化时间密切相关。与膀胱颈创面相比，前列腺部尿道创面再上皮化完成快，创面下胶原纤维形成少。因此，源自创面下前列腺基底细胞的再上皮化方式可能是机体实现由解剖修复到功能修复的最佳修复方式。

Low deceleration capacity is associated with higher stroke risk in patients with paroxysmal atrial fibrillation

Background: Deceleration capacity (DC) is a non-invasive marker for cardiac autonomic dysfunction;however, few studies have shown that the influence factors of cardiac autonomic dysfunction and the correlations between DC and stroke risk in paroxysmal atrial fibrillation (AF). We aimed to explore the influencing factors of abnormal DC and the relationships between DC and stroke risk in patients with paroxysmal AF. Methods: The study included hospitalized paroxysmal AF patients with DC measurements derived from 24-h Holter electrocardiography recordings taken between August 2015 and June 2016. Multivariable regression analysis was performed to evaluate the associations between correlated variables and abnormal DC values. The relationship between DC and ischemic stroke risk scores in patients with paroxysmal AF was analyzed. Results: We studied 259 hospitalized patients with paroxysmal AF (143 [55.2%] male, mean age 66.4 ± 12.0 years);38 patients of them showed abnormal DC values. In the univariate analysis, age, hypertension, heart failure, and previous stroke/transient ischemic attack (TIA) were significantly associated with abnormal DC values. Among these factors, a history of previous stroke/TIA (odds ratio = 2.861, 95% confidence interval: 1.356–6.039) were independently associated with abnormal DC values in patients with paroxysmal AF. The abnormal DC group showed a higher stroke risk with the score of congestive heart failure, hypertension, age >75 years, diabetes mellitus, previous stroke and TIA (CHADS2)(2.25 ± 1.48 vs. 1.40 ± 1.34, t =-4.907, P = 0.001) and CHA2DS2-vascular disease, age 65–74 years and female category (VASc)(3.76 ± 1.95 vs. 2.71 ± 1.87, t =-4.847, P = 0.001) scores. Correlation analysis showed that DC was negatively correlated with CHADS2 scores (r =-0.290, P < 0.001) and CHA2DS2-VASc scores (r =-0.263, P > 0.001). Conclusions: Lower DC is closely associated with previous stroke/TIA, and is also correlated negatively with higher stroke risk scores in patients with paroxysmal AF. It could be a potential indicator of stroke risk in paroxysmal AF patients.

Scenario analysis of hydrofluorocarbons emission reduction in China's mobile air-conditioning sector

With the Kigali Amendment(KA)coming into effect in China,the control of hydrofuorocarbons(HFCs)emissions has become more imperative.The mobile air-conditioning(MAC)sector is one of the important HFCs consumer sectors,and therefore studying its feasible mitigation paths and costs is of great significance to Chinas successful implementation of KA.This study used the bottom-up method with updated emission factors to re-evaluate the emission inventory of HFCs from the MAC sector in China from 2005 to 2020.The average annual growth rate of HFCs consumption in the MAC sector is 9.8%,and HFCs emissions have increased from 5.8(5.3-6.2)kt in 2005 to 22.2(20.6-23.8)kt in 2020,with an average annual growth rate of 8.8%.Using the Gompertz model combined with the Weibull function of vehicle survival rate,the ownership and new registrations of internal combustion engine vehicles(ICEVs)and electric vehicles(EVs)in China are predicted.The ownership of ICEVs and EVs is projected to be 310 million and 91 million in 2030,respectively and 2 million and 641 million in 2060,respectively.HFCs emissions in the MAC sector would reach 59.8(55.3-64.3)kt(80.093.0 Mt CO_(2-eq))in 2060 if without any control measure.To implement the KA,the cumulative of 1.6 Gt CO_(2-eq) emissions would be reduced.Under the other two accelerated mitigation scenarios,the MAC sector's HFCs will reach their emissions peak in 2028 and 2025 and achieve zero emissions in 2050 and 2046,respectively.Under the accelerated mitigation with recovery scenario,the cumulative emissions are only 15.0%of the business as usual(BAU)scenario.Using HFO-1234yf as the substitute,the unit abatement cost of the MAC sector is 27.3-37.4 USD _(t)^(-1)CO_(2-eq).