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Recent progress in the applications of presynaptic dopaminergic positron emission tomography imaging in parkinsonism
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作者 Yujie Yang Xinyi Li +7 位作者 Jiaying Lu Jingjie Ge Mingjia Chen Ruixin Yao Mei Tian Jian Wang Fengtao Liu Chuantao Zuo 《Neural Regeneration Research》 SCIE CAS 2025年第1期93-106,共14页
Nowadays,presynaptic dopaminergic positron emission tomography,which assesses deficiencies in dopamine synthesis,storage,and transport,is widely utilized for early diagnosis and differential diagnosis of parkinsonism.... Nowadays,presynaptic dopaminergic positron emission tomography,which assesses deficiencies in dopamine synthesis,storage,and transport,is widely utilized for early diagnosis and differential diagnosis of parkinsonism.This review provides a comprehensive summary of the latest developments in the application of presynaptic dopaminergic positron emission tomography imaging in disorders that manifest parkinsonism.We conducted a thorough literature search using reputable databases such as PubMed and Web of Science.Selection criteria involved identifying peer-reviewed articles published within the last 5 years,with emphasis on their relevance to clinical applications.The findings from these studies highlight that presynaptic dopaminergic positron emission tomography has demonstrated potential not only in diagnosing and differentiating various Parkinsonian conditions but also in assessing disease severity and predicting prognosis.Moreover,when employed in conjunction with other imaging modalities and advanced analytical methods,presynaptic dopaminergic positron emission tomography has been validated as a reliable in vivo biomarker.This validation extends to screening and exploring potential neuropathological mechanisms associated with dopaminergic depletion.In summary,the insights gained from interpreting these studies are crucial for enhancing the effectiveness of preclinical investigations and clinical trials,ultimately advancing toward the goals of neuroregeneration in parkinsonian disorders. 展开更多
关键词 aromatic amino acid decarboxylase brain imaging dopamine transporter Parkinson’s disease PARKINSONISm positron emission tomography presynaptic dopaminergic function vesicle monoamine transporter type 2
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Exploring the impact of economic growth and energy consumption on SO_(2) emissions in China based on the Environmental Kuznets Curve hypothesis
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作者 Bing-Jie Xu Yi-Fei Shen +1 位作者 Hui Qiao Zhi Gao 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2892-2900,共9页
This study aims to analysis the influence of economic growth(EG)and energy consumption(EC)on sulfur dioxide emissions(SE)in China.Accordingly,this study explores the link between EG,EC,and SE for 30 provinces in China... This study aims to analysis the influence of economic growth(EG)and energy consumption(EC)on sulfur dioxide emissions(SE)in China.Accordingly,this study explores the link between EG,EC,and SE for 30 provinces in China over the span of 2000-2019.This study also analyzes cross-sectional dependence tests,panel unit root tests,Westerlund panel cointegration tests,Dumitrescu-Hurlin(D-H)causality tests.According to the test results,there is an inverted U-shaped association between EG and SE,and the assumption of the Environmental Kuznets Curve(EKC)is verified.The signs of EG and EC in the fixed effect(FE)and random effect(RE)methods are in line with those in the dynamic ordinary least squares(DOLS),fully modified ordinary least squares(FMOLS)and autoregressive distributed lag(ARDL)estimators.Moreover,the results verified that EC can obviously positive impact the SE.To reduce SE in China,government and policymakers can improve air quality by developing cleaner energy sources and improving energy efficiency.This requires the comprehensive use of policies,regulations,economic incentives,and public participation to promote sustainable development. 展开更多
关键词 SO_(2)emissions Economic growth Energy consumption EKC China
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Quantification of CO_(2) Emissions from Three Power Plants in China Using OCO-3 Satellite Measurements
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作者 Yang YANG Minqiang ZHOU +3 位作者 Wei WANG Zijun NING Feng ZHANG Pucai WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第11期2276-2288,共13页
Coal-fired power plants are a major carbon source in China. In order to assess the evaluation of China's carbon reduction progress with the promise made on the Paris Agreement, it is crucial to monitor the carbon ... Coal-fired power plants are a major carbon source in China. In order to assess the evaluation of China's carbon reduction progress with the promise made on the Paris Agreement, it is crucial to monitor the carbon flux intensity from coal-fired power plants. Previous studies have calculated CO_(2) emissions from point sources based on Orbiting Carbon Observatory-2 and-3(OCO-2 and OCO-3) satellite measurements, but the factors affecting CO_(2) flux estimations are uncertain. In this study, we employ a Gaussian Plume Model to estimate CO_(2) emissions from three power plants in China based on OCO-3 XCO_(2) measurements. Moreover, flux uncertainties resulting from wind information, background values,satellite CO_(2) measurements, and atmospheric stability are discussed. This study highlights the CO_(2) flux uncertainty derived from the satellite measurements. Finally, satellite-based CO_(2) emission estimates are compared to bottom-up inventories.The satellite-based CO_(2) emission estimates at the Tuoketuo and Nongliushi power plants are ~30 and ~10 kt d^(-1) smaller than the Open-Data Inventory for Anthropogenic Carbon dioxide(ODIAC) respectively, but ~10 kt d^(-1) larger than the ODIAC at Baotou. 展开更多
关键词 OCO-3 power plant CO_(2)emission Gaussian Plume model
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Regulatory potential of soil available carbon,nitrogen,and functional genes on N_(2)O emissions in two upland plantation systems
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作者 Peng Xu Mengdie Jiang +4 位作者 Imran Khan Muhammad Shaaban Hongtao Wu Barthelemy Harerimana Ronggui Hu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第8期2792-2806,共15页
Dynamic nitrification and denitrification processes are affected by changes in soil redox conditions,and they play a vital role in regulating soil N_(2)O emissions in rice-based cultivation.It is imperative to underst... Dynamic nitrification and denitrification processes are affected by changes in soil redox conditions,and they play a vital role in regulating soil N_(2)O emissions in rice-based cultivation.It is imperative to understand the influences of different upland crop planting systems on soil N_(2)O emissions.In this study,we focused on two representative rotation systems in Central China:rapeseed–rice(RR)and wheat–rice(WR).We examined the biotic and abiotic processes underlying the impacts of these upland plantings on soil N_(2)O emissions.The results revealed that during the rapeseed-cultivated seasons in the RR rotation system,the average N_(2)O emissions were 1.24±0.20 and 0.81±0.11 kg N ha^(–1)for the first and second seasons,respectively.These values were comparable to the N_(2)O emissions observed during the first and second wheat-cultivated seasons in the WR rotation system(0.98±0.25 and 0.70±0.04 kg N ha^(–1),respectively).This suggests that upland cultivation has minimal impacts on soil N_(2)O emissions in the two rotation systems.Strong positive correlations were found between N_(2)O fluxes and soil ammonium(NH_(4)^(+)),nitrate(NO_(3)^(–)),microbial biomass nitrogen(MBN),and the ratio of soil dissolved organic carbon(DOC)to NO_(3)^(–)in both RR and WR rotation systems.Moreover,the presence of the AOA-amoA and nirK genes were positively associated with soil N_(2)O fluxes in the RR and WR systems,respectively.This implies that these genes may have different potential roles in facilitating microbial N_(2)O production in various upland plantation models.By using a structural equation model,we found that soil moisture,mineral N,MBN,and the AOA-amoA gene accounted for over 50%of the effects on N_(2)O emissions in the RR rotation system.In the WR rotation system,soil moisture,mineral N,MBN,and the AOA-amoA and nirK genes had a combined impact of over 70%on N_(2)O emissions.These findings demonstrate the interactive effects of functional genes and soil factors,including soil physical characteristics,available carbon and nitrogen,and their ratio,on soil N_(2)O emissions during upland cultivation seasons under rice-upland rotations. 展开更多
关键词 upland-rice cultivation N_(2)O emission regulatory factors functional genes
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Refining the Factors Affecting N_(2)O Emissions from Upland Soils with and without Nitrogen Fertilizer Application at a Global Scale
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作者 Wenqian JIANG Siqi LI +5 位作者 Yong LI Meihui WANG Bo WANG Ji LIU Jianlin SHEN Xunhua ZHENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第9期1804-1820,共17页
Nitrous oxide(N_(2)O)is a long-lived greenhouse gas that mainly originates from agricultural soils.More and more studies have explored the sources,influencing factors and effective mitigation measures of N_(2)O in rec... Nitrous oxide(N_(2)O)is a long-lived greenhouse gas that mainly originates from agricultural soils.More and more studies have explored the sources,influencing factors and effective mitigation measures of N_(2)O in recent decades.However,the hierarchy of factors influencing N_(2)O emissions from agricultural soils at the global scale remains unclear.In this study,we carry out correlation and structural equation modeling analysis on a global N_(2)O emission dataset to explore the hierarchy of influencing factors affecting N_(2)O emissions from the nitrogen(N)and non-N fertilized upland farming systems,in terms of climatic factors,soil properties,and agricultural practices.Our results show that the average N_(2)O emission intensity in the N fertilized soils(17.83 g N ha^(-1)d^(-1))was significantly greater than that in the non-N fertilized soils(5.34 g N ha^(−1) d^(−1))(p<0.001).Climate factors and agricultural practices are the most important influencing factors on N_(2)O emission in non-N and N fertilized upland soils,respectively.For different climatic zones,without fertilizer,the primary influence factors on soil N_(2)O emissions are soil physical properties in subtropical monsoon zone,whereas climatic factors are key in the temperate zones.With fertilizer,the primary influence factors for subtropical monsoon and temperate continental zones are soil physical properties,while agricultural measures are the main factors in the temperate monsoon zone.Deploying enhanced agricultural practices,such as reduced N fertilizer rate combined with the addition of nitrification and urease inhibitors can potentially mitigate N_(2)O emissions by more than 60%in upland farming systems. 展开更多
关键词 N_(2)O emissions influencing factors nitrogen cycling upland farming systems
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Inversion of O_(2) 1.27 μm nightglow emissions: A climatological analysis using satellite Limb-Viewed spectra and Harmonic analysis method
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作者 YiYi Sui YaJun Zhu +2 位作者 QiuYu Chen MaoSheng He JiYao Xu 《Earth and Planetary Physics》 EI CAS CSCD 2024年第4期632-640,共9页
This study employs a linear inversion algorithm to retrieve volume emission rates(VERs)of molecular O_(2) nightglow at 1.27μm,utilizing Limb-Viewed spectra obtained from the SCanning Imaging Absorption spectroMeter f... This study employs a linear inversion algorithm to retrieve volume emission rates(VERs)of molecular O_(2) nightglow at 1.27μm,utilizing Limb-Viewed spectra obtained from the SCanning Imaging Absorption spectroMeter for Atmospheric for CHartographY(SCIAMACHY)payload on board the Envisat satellite.The retrieved results are compared with VERs data from the SABER payload on the Thermosphere Ionosphere Mesosphere Energetics and Dynamics(TIMED)satellite,exhibiting consistency.This will help to facilitate accurate revelation of spatial distribution and periodic variation in O_(2) nightglow.VERs are extracted monthly within the altitude range of 75-110 km from 2002 to 2012,yielding a climatology of spatial and temporal distributions.The meridional structure exhibits two maxima,at the equator and at 45°N.Between August and October,the VERs exhibit a meridional bimodal structure,with the weaker one above the equator and the stronger one above 45°N.In April,the VERs reach their annual maximum.Additionally,harmonic analysis reveals significant temporal variations on different scales.The emission shows characteristics of annual and semi-annual variation,and a non-linear long-term trend associated with solar cycle activity. 展开更多
关键词 VERs O_(2)1.27μm nightglow SCIAmACHY
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Impacts of forest plantation programs on sectoral CO_(2) emissions regionally in New Zealand
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作者 Saeed Solaymani Andrew Dunningham 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第6期13-28,共16页
Investing in projects that support environmental benefits,such as tree harvesting,has the potential to reduce air pollution levels in the atmosphere in the future.However,this kind of investment may increase the curre... Investing in projects that support environmental benefits,such as tree harvesting,has the potential to reduce air pollution levels in the atmosphere in the future.However,this kind of investment may increase the current level of emissions.Therefore,it is necessary to estimate how much the policy affects the current level of CO_(2) emissions.This makes sure the policy doesn’t increase the level of CO_(2) emis-sions.This study aims to analyze the effect of the One Bil-lion Trees program on CO_(2) emissions in New Zealand by employing the 2020 input–output table analysis.This inves-tigation examines the direct and indirect effects of policy on both the demand and supply sides across six regions of New Zealand.The results of this study for the first year of plantation suggest that the policy increases the level of CO_(2) emissions in all regions,especially in the Waikato region.The direct and indirect impact of the policy leads to 64 kt of CO_(2) emissions on the demand side and 270 kt of CO_(2) emis-sions on the supply side.These lead to 0.19 and 0.74%of total CO_(2) emissions being attributed to investment shocks.Continuing the policy is recommended,as it has a low effect on CO_(2) emissions.However,it is crucial to prioritize the use of low-carbon machinery that uses fossil fuels during the plantation process. 展开更多
关键词 Regional input–output analysis Forest investment program Sectoral CO_(2) emissions Environmental policies Supply-side policy Demand-side policy
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Combustion and pollutant emission characteristics of coal in a pressurized fluidized bed under O_2/ CO_2 atmosphere 被引量:4
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作者 段元强 段伦博 +1 位作者 胡海华 赵长遂 《Journal of Southeast University(English Edition)》 EI CAS 2015年第2期188-193,共6页
The pressurized combustion experiments of bituminous coal and lignite under air and O2/CO2 atmospheres were conducted to study the influences of pressure and atmosphere on combustion and the CO, NO, SO2 release proces... The pressurized combustion experiments of bituminous coal and lignite under air and O2/CO2 atmospheres were conducted to study the influences of pressure and atmosphere on combustion and the CO, NO, SO2 release process. Two indices, the maximum concentration and the total emission, were applied to quantitatively evaluate the influence of several different operating parameters such as pressure, atmosphere and temperature on the formation of NO and SO2 during coal combustion in the fluidized bed. The experimental results show that the releasing profiles of CO, NO and SO2 during coal combustion under a pressurized oxy- fuel atmosphere are similar to those under a pressurized air atmosphere, and the curves of measured gas components are all unimodal. Under the oxy-fuel condition, pressure increasing from 0.1 to 0.7 MPa can cause the inhibition of NO and SO2 emission. The elevation of temperature can lead to an increase in the maximum concentration and the total production of NO and SO2, and the increase under atmospheric pressure is higher than that under high pressure. 展开更多
关键词 pressurized oxy-fuel combustion fluidized bed SO2 emission NO emission
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Effects of Reduced Nitrogen Fertilization and Biochar Application on CO_2 and N_2O Emissions from a Summer Maize-Winter Wheat Rotation Field in North China 被引量:1
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作者 韩雪 范靖尉 +4 位作者 白晋华 任寰宇 李迎春 刁田田 郭李萍 《Agricultural Science & Technology》 CAS 2016年第12期2800-2808,共9页
This experiment was conducted in Xinxiang, Henan from June 2013 to June 2014. Total four treatments were designed including farmers ’ common practice (F, 250 kg/hm^2), 80% F (LF, 200 kg/hm^2), 80% F+biochar (LF... This experiment was conducted in Xinxiang, Henan from June 2013 to June 2014. Total four treatments were designed including farmers ’ common practice (F, 250 kg/hm^2), 80% F (LF, 200 kg/hm^2), 80% F+biochar (LFC) and no fertilizer (CK) to measure the dynamic emissions of CO2 and N2O from a summer maize-winter wheat field by static chamber-gas chromatography method. The results showed that the soil CO2 emission was 21.8-1 022.7 mg/(m^2·h), and was mainly influenced by soil temperature and moisture content. During the growth of summer maize, the soil CO2 emission was more significantly affected by soil moisture con-tent; and in winter wheat growing season, it was more significantly affected by soil temperature in the top 5 cm. The LF and LFC treatments significantly reduced the soil cumulative CO2 emission, especial y during the growth of winter wheat. Fertiliza-tion and irrigation were the main factors influencing the soil N2O emission. The soil N2O emission during the fertilization period accounted for 73.9%-74.5% and 40.5%-43.6% of the soil cumulative N2O emission during the summer maize-and winter wheat-growing season, respectively. The peak of emission fluxes was determined by fertilization amount, while the occurrence time of emission peak and emission re-duction effect were influenced by irrigation. The LF treatment reduced the soil cu-mulative N2O emission by 15.7%-16.8% and 18.1%-18.5% during the growth period of summer maize and winter wheat, respectively. Reduced nitrogen fertilization is an effective way for reducing N2O emission in intensive high-yielding farmland. Under a suitable nitrogen level (200 kg/hm^2), the application of biochar showed no significant effect on the soil N2O emission in a short term. The N2O emission factors of the L and LF treatments were 0.60% and 0.56%, respectively. ln the intensive high-yield-ing farmland of North China, reducing the nitrogen application amount is an appro-priate measure to mitigate greenhouse gas emissions without crop yield loss. 展开更多
关键词 Reduced nitrogen fertilization BIOCHAR Greenhouse gas emissions N2O emission Winter wheat-summer maize
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M2型巨噬细胞衍生外泌体促进小胶质细胞M2型极化
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作者 方俊 魏伟 +5 位作者 薛亚婷 崔臣龙 卫嘉晟 石筱 杨丽娟 杨保仲 《中国组织工程研究》 CAS 北大核心 2025年第25期5320-5327,共8页
背景:目前对于M2型巨噬细胞衍生外泌体的研究多集中于促进伤口愈合及成骨细胞的增殖和分化,而很少有研究关注其对小胶质细胞表型的调控作用。目的:探讨M2型巨噬细胞衍生外泌体对于小胶质细胞的表型调控作用及分子机制。方法:①提取骨髓... 背景:目前对于M2型巨噬细胞衍生外泌体的研究多集中于促进伤口愈合及成骨细胞的增殖和分化,而很少有研究关注其对小胶质细胞表型的调控作用。目的:探讨M2型巨噬细胞衍生外泌体对于小胶质细胞的表型调控作用及分子机制。方法:①提取骨髓原代巨噬细胞,用50 ng/m L白细胞介素4刺激巨噬细胞24 h促进巨噬细胞M2型极化,流式细胞术和细胞免疫荧光鉴定M2型巨噬细胞标志物CD206;②提取和鉴定M2型巨噬细胞衍生外泌体;③将小胶质细胞BV2随机分为3组:对照组、脂多糖组、治疗组,对照组不做处理,脂多糖组加入500 ng/m L脂多糖干预24 h,治疗组同时加入500 ng/m L脂多糖和25μg/m L M2型巨噬细胞衍生外泌体干预24 h,ELISA检测培养上清中肿瘤坏死因子α和白细胞介素10的分泌量,q RT-PCR检测细胞中诱导型一氧化氮合酶、精氨酸酶1、白细胞介素1β和白细胞介素10的m RNA表达,Western blot检测诱导型一氧化氮合酶、精氨酸酶1的蛋白表达以及核因子κB信号通路相关蛋白表达。结果与结论:①ELISA结果显示,与对照组相比,脂多糖组肿瘤坏死因子α分泌明显增多;与脂多糖组相比,治疗组肿瘤坏死因子α的分泌减少而白细胞介素10的分泌增多;②q RT-PCR结果显示,与对照组相比,脂多糖组白细胞介素1β、诱导型一氧化氮合酶m RNA表达升高;与脂多糖组相比,治疗组白细胞介素1β、诱导型一氧化氮合酶m RNA表达降低,白细胞介素10、精氨酸酶1 m RNA表达升高;③Western blot结果显示,与对照组相比,脂多糖组诱导型一氧化氮合酶蛋白表达升高;与脂多糖组相比,治疗组诱导型一氧化氮合酶蛋白表达降低,而精氨酸酶1蛋白表达升高;(4)与对照组相比,脂多糖组核因子κB信号通路中P65、p-IκB-α蛋白表达降低;与脂多糖组相比,治疗组P65、p-IκB-α蛋白表达升高。结果表明:M2型巨噬细胞衍生外泌体可以显著抑制脂多糖诱导小胶质细胞的炎症反应,促进抗炎因子白细胞介素10的表达,抑制促炎因子肿瘤坏死因子α、白细胞介素1β的表达,促进小胶质细胞表型由M1型向M2型极化,其机制可能与M2型巨噬细胞衍生外泌体抑制核因子κB信号通路激活有关。 展开更多
关键词 m2巨噬细胞 外泌体 小胶质细胞 炎症 NF-ΚB信号通路 神经病理性疼痛 极化
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GRA BASED ANALYSIS ON FACTORS INFLUENCING CO_2 EMISSIONS IN CHINA 被引量:1
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作者 董锋 李晓晖 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期152-158,共7页
How to achieve the objective of reducing CO2 emissions has been an academic focus in China recently. The factors influencing CO2 emissions are the vital issue to accomplish the arduous target. Firstly, three influenti... How to achieve the objective of reducing CO2 emissions has been an academic focus in China recently. The factors influencing CO2 emissions are the vital issue to accomplish the arduous target. Firstly, three influential factors, the energy consumption, the proportion of tertiary industry in gross domestic product (GDP), and the degree of dependence on foreign trade, are carefully selected, since all of them have closer grey relation with China's COz emissions compared with others when the grey relational analysis (GRA) method is applied. The study highlights co-integration relation of these four variables using the co-integration analysis method. And then a long-term co-integration equation and a short-term error correction model of China's CO2 emissions are devel- oped. Finally, the comparison is exerted between the forecast value and the actual value of China's CO2 emissions based on error correction model. The results and the relevant statistics tests show that the pro- posed model has better explanation capability and credibility. 展开更多
关键词 grey relational analysis(GRA) CO2 emissions co-integration test error correction model
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Effect of Light Quality and Intensity on N_2O and NO_X(NO, NO_2)Emissions from Rice Phyllosphere and Roots at Tillering Stage in a Liquid Culture Medium System
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作者 徐胜光 李冰 +5 位作者 刘佳妮 陈泽斌 余磊 赵凤 耿开友 王定康 《Agricultural Science & Technology》 CAS 2016年第3期633-641,共9页
[Objective] N2Oand NOX(NO, NO2) are important nitrogen oxides gases(NOGs) in paddy fields, and rice plants play important roles in NOG emissions in paddy fields. However, the source of NOG emissions from rice phyl... [Objective] N2Oand NOX(NO, NO2) are important nitrogen oxides gases(NOGs) in paddy fields, and rice plants play important roles in NOG emissions in paddy fields. However, the source of NOG emissions from rice phyllosphere and roots and their relationship to light quality and intensity still remain unclear. In this study, the relationship between light quality, intensity and N2 O, NOX(NO, NO2) emissions from rice phyllosphere and roots at tillering stage was investigated to clarify the contribution of rice plants to N2Oand NOX(NO, NO2) emissions and analyze the mechanism of light control, aiming at providing a scientific basis for revealing how light-control technology affects NOG emissions from rice at tillering stage in paddy fields. [Method] In this study, nitrogen content was controlled by a hydroponic system. A small electric incubator was used for light control. A simultaneous determination was designed to investigate the effect of different weak light qualities(yellow, green, white, red and blue lights) and intensities(dark, 0 lx; very weak, 2 000lx; weak, 4 000 lx; moderate, 6 000 lx; strong, 8 000 lx) on N2Oand NOXemissions from rice phyllosphere and roots at tillering stage in a liquid culture medium system. N2Oconcentration in air samples was determined by gas chromatography within 12 h, and NOX(NO, NO2) concentration was analyzed using 42 i NO- NO2-NOXgas analyzer. [Result] The results showed that:(1) Under a constant nitrogen condition(NH4NO3-N, 90 mg/L) when rice seedlings were treated with moderate(6 000lx) and strong(8 000 lx) light, the average emission rate of N2Oand NO from rice phyllosphere at tillering stage was 27.08, 32.33 μg/(pot·h) and 0.114, 0.057 μg/(pot·h),respectively, accounting for 57.38%, 58.65% and 9.65%, 4.52% of the total release of N2Oand NO from the whole rice plant, respectively. It implicated that rice phyllosphere is an important source of N2Oemission at tillering stage in paddy fields.(2)When rice seedlings were treated with yellow, green, white, red and blue LED lights under a constant light intensity(1 600 lx), the average emission rate of N2Ofrom rice phyllosphere was 6.83, 9.40, 9.73, 2.82 and 4.08 μg/(pot·h), respectively. Compared with green and yellow LED lights, N2Oemission from rice phyllosphere and roots at tillering stage was inhibited markedly by red(3 000 lx) and blue(2 500 lx)LED lights(P0.01). In addition, NO emission from rice phyllosphere was enhanced significantly by white and red LED lights, while NO emissions from rice phyllosphere and roots were inhibited by blue light synchronously. Nevertheless, no evident NO2 emission from rice phyllosphere and roots was detected under the same condition.(3) Within the range of 0-8 000 lx, NO and N2Oemissions from rice roots and N2Oemission from rice phyllosphere increased with the enhancement of light intensity. In contrast, NO emission from rice phyllosphere was inhibited remarkably by moderate(6 000 lx) and strong(8 000 lx) light(P〈 0.01). [Conclusion] Rice seedlings mainly exhibited net emissions of NO2 from the phyllosphere and roots.N2Oand NOX(NO, NO2) emissions from rice phyllosphere and roots at tillering stage could be inhibited by adjusting the composition of visible light(synchronously increasing the proportions of red and blue lights) and appropriately controlling daytime light intensity. 展开更多
关键词 ILLUmINATION RICE N2O NOX(NO NO2 emission
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Nitrification and Denitrification Activities and N_2O Emission of Orchard Soils Cultivated for Different Periods of Time
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作者 张玉树 丁洪 +3 位作者 胡晓霞 张生才 秦胜金 郑祥洲 《Agricultural Science & Technology》 CAS 2012年第4期843-848,共6页
[Objective] The aim was to investigate the differences in nitrification and denitrification activities and the N20 emission of orchard soils cultivated for different periods of time. [Method] Incubation experiment was... [Objective] The aim was to investigate the differences in nitrification and denitrification activities and the N20 emission of orchard soils cultivated for different periods of time. [Method] Incubation experiment was conducted to determine the ni- trification and denitrification activities and N20 emission of three types of orchard soil samples that had been cultivated for 5, 12 and 20 years, respectively, by using the virgin soil sample as control. [Result] After 26 d of incubation, the nitrification rates of nitrogen fertilizer in the virgin soil sample and the orchard soil samples cultivated for 5, 12 and 20 years were 6.85%, 10.26%, 13.29% and 12.90%, respectively, which were positively correlated with content of soil organic matter, ammonium nitro- gen and total nitrogen (P〈0.05), and negatively correlated with soil carbon-nitrogen ratio and pH value (P〈0.05). The denitrification activities of these soil samples in- creased with the increase of cultivation years. The amount of nitrogen loss by deni- trification accounted for 0.01%-3.11% of the amount of fertilizer nitrogen, and had a positive correlation with the content of soil organic matter (P〈0.05). The N20 emis- sions of orchard soil samples were higher than that of the virgin soil samples (P〈 0.05). [Conclusion] In South China, the nitrification activity of orchard soil is relatively low, but it has a tendency to increase as the cultivation years increases; the denitri- fication activity is relatively high, and increases significantly with the increase of culti- vation years. 展开更多
关键词 Orchard soil NITRIFICATION DENITRIFICATION N2O emission
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Effect of water stress on N_2O emission rate of 5 tree species
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作者 王淼 李秋荣 +1 位作者 肖冬梅 王长科 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期19-23,J001,共6页
The N2O emission rates, photosynthesis, respiration and stomatal conductance of the dominant tree species from broadleaf/Korean pine forest in Changbai Mountain were measured by simulated water stress with the closed ... The N2O emission rates, photosynthesis, respiration and stomatal conductance of the dominant tree species from broadleaf/Korean pine forest in Changbai Mountain were measured by simulated water stress with the closed bag-gas chromatography. A total of five species seedlings were involved in this study, i.e.,Pinus koraiensis Sieb. et Zucc,Fraxinus mandshurica Rupr,Juglans mandshurica Maxim,Tilia amurensis Rupr, andQuercus mongolica Fisch. ex Turcz.. The results showed that the stomatal conductance, net photosynthetic rate and N2O emission of leaves were significantly reduced under the water stress. The stoma in the leaves of trees is the main pathway of N2O emission. N2O emission in the trees mainly occurred during daytime. N2O emission rates were different in various tree specie seedlings at the same water status. In the same tree species, N2O emission rates decreased as the reduction of soil water contents. At different soil water contents (MW, LW) the N2O emission rates ofPinus koraiensis decreased by 34.43% and 100.6% of those in normal water condition, respectively. In broadleaf arbor decreased by 31.93% and 86.35%, respectively. Under different water stresses N2O emission rates in five tree species such asPinus koraiensis, Fraxinus mandshurica, Juglans mandshurica, Tilia amurensis, andQuercus mongolica were 38.22, 14.44, 33.02, 16.48 and 32.33 ngN2O·g?1DW·h?1, respectively. Keywords Trees - N2O emission rate - Soil water stress - broadleaf/Korean pine forest - Changbai Mountain CLC number S718.55 Document code A Foundation item: This project was supported by the National Natural Science Foundation of China (No. 30271068), the grant of the Knowledge Innovation Program of Chinese Academy of Sciences (KZ-CX-SW-01-01B-10), and the Special Funds for Major State Basic Research Program of China (No. G1999043407)Biography: Wang Miao (1964-), male, associate professor in Institute of Applied Ecology, Chinese Academy of Science, Shenyang 110016, P. R. China.Responsible editor: Song Funan 展开更多
关键词 Trees N2O emission rate Soil water stress broadleaf/Korean pine forest Changbai mountain
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Recombinant chitinase-3-like protein 1 alleviates learning and memory impairments via M2 microglia polarization in postoperative cognitive dysfunction mice
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作者 Yujia Liu Xue Han +6 位作者 Yan Su Yiming Zhou Minhui Xu Jiyan Xu Zhengliang Ma Xiaoping Gu Tianjiao Xia 《Neural Regeneration Research》 SCIE CAS 2025年第9期2727-2736,共10页
Postoperative cognitive dysfunction is a seve re complication of the central nervous system that occurs after anesthesia and surgery,and has received attention for its high incidence and effect on the quality of life ... Postoperative cognitive dysfunction is a seve re complication of the central nervous system that occurs after anesthesia and surgery,and has received attention for its high incidence and effect on the quality of life of patients.To date,there are no viable treatment options for postoperative cognitive dysfunction.The identification of postoperative cognitive dysfunction hub genes could provide new research directions and therapeutic targets for future research.To identify the signaling mechanisms contributing to postoperative cognitive dysfunction,we first conducted Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses of the Gene Expression Omnibus GSE95426 dataset,which consists of mRNAs and long non-coding RNAs differentially expressed in mouse hippocampus3 days after tibial fracture.The dataset was enriched in genes associated with the biological process"regulation of immune cells,"of which Chill was identified as a hub gene.Therefore,we investigated the contribution of chitinase-3-like protein 1 protein expression changes to postoperative cognitive dysfunction in the mouse model of tibial fractu re surgery.Mice were intraperitoneally injected with vehicle or recombinant chitinase-3-like protein 124 hours post-surgery,and the injection groups were compared with untreated control mice for learning and memory capacities using the Y-maze and fear conditioning tests.In addition,protein expression levels of proinflammatory factors(interleukin-1βand inducible nitric oxide synthase),M2-type macrophage markers(CD206 and arginase-1),and cognition-related proteins(brain-derived neurotropic factor and phosphorylated NMDA receptor subunit NR2B)were measured in hippocampus by western blotting.Treatment with recombinant chitinase-3-like protein 1 prevented surgery-induced cognitive impairment,downregulated interleukin-1βand nducible nitric oxide synthase expression,and upregulated CD206,arginase-1,pNR2B,and brain-derived neurotropic factor expression compared with vehicle treatment.Intraperitoneal administration of the specific ERK inhibitor PD98059 diminished the effects of recombinant chitinase-3-like protein 1.Collectively,our findings suggest that recombinant chitinase-3-like protein 1 ameliorates surgery-induced cognitive decline by attenuating neuroinflammation via M2 microglial polarization in the hippocampus.Therefore,recombinant chitinase-3-like protein1 may have therapeutic potential fo r postoperative cognitive dysfunction. 展开更多
关键词 Chil1 hippocampus learning and memory m2 microglia NEUROINFLAmmATION postoperative cognitive dysfunction(POCD) recombinant CHI3L1
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ISSUES AND SUGGESTIONS ON LEVYING SO_2 EMISSION GHARGES TO THERMAL POWER PLANTS
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作者 王志轩 《Electricity》 2002年第4期3-6,共4页
This paper analyzes 9 essentials in trial collecting SO2 emission charges based on the relevant legislative policies, summarizes and analyzes the actual practices of collecting and using SO2 emission charges in power ... This paper analyzes 9 essentials in trial collecting SO2 emission charges based on the relevant legislative policies, summarizes and analyzes the actual practices of collecting and using SO2 emission charges in power industry, and combining the status of power system reform, puts forward some recommendations about reasonably collecting and using SO2 emission charges and prompting power plants to take measures of desulfurization. 展开更多
关键词 thermal power plant SO2 control emission charges POLICY
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A combination of straw incorporation and polymer-coated urea offsets soil ammonia and nitrous oxide emissions in winter wheat fields
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作者 Xiaoyun Wang Yajie Tian +3 位作者 Qianhui Zhang Zhengxin Zhao Rui Wang Huanjie Cai 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1718-1736,共19页
The combined effects of straw incorporation(SI)and polymer-coated urea(PCU)application on soil ammonia(NH_(3))and nitrous oxide(N_(2)O)emissions from agricultural fields have not been comprehensively evaluated in Nort... The combined effects of straw incorporation(SI)and polymer-coated urea(PCU)application on soil ammonia(NH_(3))and nitrous oxide(N_(2)O)emissions from agricultural fields have not been comprehensively evaluated in Northwest China.We conducted a two-year field experiment to assess the effects of combining SI with either uncoated urea(U)or PCU on soil NH_(3)emissions,N_(2)O emissions,winter wheat yields,yield-scaled NH_(3)(/NH_(3)),and yield-scaled N_(2)O(/N_(2)O).Five treatments were investigated,no nitrogen(N)fertilizer(N_(0)),U application at 150 kg N ha-1 with and without SI(SI+U and S_(0)+U),and PCU application at 150 kg N ha^(-1) with and without SI(SI+PCU and S_(0)+PCU).The results showed that the NH_(3);emissions increased by 20.98-34.35%following Sl compared to straw removal,mainly due to increases in soil ammonium(NH_(4)^(+)-N)content and water-flled pore space(WFPS).SI resulted in higher N_(2)O emissions than under the So scenario by 13.31-49.23%due to increases in soil inorganic N(SIN)contents,WFPS,and soil microbial biomass.In contrast,the PCU application reduced the SIN contents compared to the U application,reducing the NH_(3)and N_(2)O emissions by 45.99-58.07 and 18.08-53.04%,respectively.Moreover,no significant positive effects of the SI or PCU applications on the winter wheat yield were observed.The lowest /NH_(3) and /N_(2)O values were observed under the S_(0)+PCU and SI+PCU treatments.Our results suggest that single PCU applications and their combination with straw are the optimal agricultural strategies for mitigating gaseous N emissions and maintaining optimal winter wheat yields in Northwest China. 展开更多
关键词 straw incorporation polymer-coated urea NH_(3)and N_(2)O emissions winter wheat yields
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Mitigating Carbon Emissions:A Comprehensive Analysis of Transitioning to Hydrogen-Powered Plants in Japan’s Energy Landscape Post-Fukushima
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作者 Nugroho Agung Pambudi Andrew Chapman +2 位作者 Alfan Sarifudin Desita Kamila Ulfa Iksan Riva Nanda 《Energy Engineering》 EI 2024年第5期1143-1159,共17页
One of the impacts of the Fukushima disaster was the shutdown of all nuclear power plants in Japan,reaching zero production in 2015.In response,the country started importing more fossil energy including coal,oil,and n... One of the impacts of the Fukushima disaster was the shutdown of all nuclear power plants in Japan,reaching zero production in 2015.In response,the country started importing more fossil energy including coal,oil,and natural gas to fill the energy gap.However,this led to a significant increase in carbon emissions,hindering the efforts to reduce its carbon footprint.In the current situation,Japan is actively working to balance its energy requirements with environmental considerations,including the utilization of hydrogen fuel.Therefore,this paper aims to explore the feasibility and implications of using hydrogen power plants as a means to reduce emissions,and this analysis will be conducted using the energy modeling of the MARKAL-TIMES Japan framework.The hydrogen scenario(HS)is assumed with the extensive integration of hydrogen into the power generation sector,supported by a hydrogen import scheme.Additionally,this scenario will be compared with the Business as Usual(BAU)scenario.The results showed that the generation capacities of the BAU and HS scenarios have significantly different primary energy supplies.The BAU scenario is highly dependent on fossil fuels,while the HS scenario integrates hydrogen contribution along with an increase in renewable energy,reaching a peak contribution of 2,160 PJ in 2050.In the HS scenario,the target of reducing CO_(2) emissions by 80%is achieved through significant hydrogen penetration.By 2050,the total CO_(2) emissions are estimated to be 939 million tons for the BAU scenario and 261 million tons for the Hydrogen scenario.In addition,the contribution of hydrogen to electricity generation is expected to be 153 TWh,smaller than PV and wind power. 展开更多
关键词 Business as usual(BAU)scenario hydrogen scenario CO_(2)emissions power generation sector
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Denitrification Losses and N_2O Emissions from Nitrogen Fertilizer Applied to a Vegetable Field 被引量:28
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作者 CAO Bing He Fa-Yun +2 位作者 Xu Qiu-Ming Yin Bin CAI Gui-Xin 《Pedosphere》 SCIE CAS CSCD 2006年第3期390-397,共8页
A field experiment was conducted on Chinese cabbage (Brassica campestris L. ssp. pekinensis (Lour.) Olsson) in a Nanjing suburb in 2003. The experiment included 4 treatments in a randomized complete block design w... A field experiment was conducted on Chinese cabbage (Brassica campestris L. ssp. pekinensis (Lour.) Olsson) in a Nanjing suburb in 2003. The experiment included 4 treatments in a randomized complete block design with 3 replicates: zero chemical fertilizer N (CK); urea at rates of 300 kg N ha^-1 (U300) and 600 kg N ha^-1 (U600), both as basal and two topdressings; and polymer-coated urea at a rate of 180 kg N ha^-1 (PCU180) as a basal application. The acetylene inhibition technique was used to measure denitrification (N2 + N2O) from intact soil cores and N2O emissions in the absence of acetylene. Results showed that compared to (3K total denitrification losses were significantly greater (P ≤ 0.05) in the PCU180, U300, and U600 treatments,while N2O emissions in the U300 and U600 treatments were significantly higher (P ≤ 0.05) than (3K. In the U300 and U600 treatments peaks of denitrification and N2O emission were usually observed after N application. In the polymer-coated urea treatment (PCU180) during the period 20 to 40 days after transplanting, higher denitrification rates and N2O fluxes occurred. Compared with urea, polymer-coated urea did not show any effect on reducing denitrification losses and N2O emissions in terms of percentage of applied N. As temperature gradually decreased from transplanting to harvest, denitrification rates and N2O emissions tended to decrease. A significant (P ≤0.01) positive correlation occurred between denitrification (r = 0.872) or N2O emission (r = 0.781) flux densities and soil temperature in the CK treatment with a stable nitrate content during the whole growing season. 展开更多
关键词 denitrification loss N2O emission polymer-coated urea UREA vegetable field
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Correlation of brain cell glucose metabolism and patient's condition in children with epileptic encephalopathy An assessment using fluorine-18-fluoro-2-deoxy-D-glucose positron emission computed tomography 被引量:5
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作者 Qiongxiang Zhai Yuxiong Guo +4 位作者 Yuxin Zhang Zhihong Chen Jian Ding Juan Gui Ying Hao 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第32期2521-2526,共6页
We examined a total of 16 children with epileptic encephalopathy using fluorine-18-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission computed tomography (PET), magnetic resonance imaging (MRI) and electroence... We examined a total of 16 children with epileptic encephalopathy using fluorine-18-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission computed tomography (PET), magnetic resonance imaging (MRI) and electroencephalography. Children with infantile spasms showed significant mental retardation, severely abnormal electroencephalogram recordings, and bilateral diffuse cerebral cortex hypometabolism with I^F-FDG PET imaging. MRI in these cases showed brain atrophy, multi-micropolygyria, macrogyria, and porencephalia. In cases with Lennox-Gastaut syndrome, 18F-FDG PET showed bilateral diffuse glucose hypometabolism, while MRI showed cortical atrophy, heterotopic gray matter and tuberous sclerosis. MRI in cases with myoclonic encephalopathy demonstrated bilateral frontal and temporal cortical and white matter atrophy and 18F-FDG PET imaging showed bilateral frontal lobe atrophy with reduced bilateral frontal cortex, occipital cortex, temporal cortex and cerebellar glucose uptake. In children who could not be clearly classified, MRI demonstrated cerebral cortical atrophy and ~aF-FDG PET exhibited multifocal glucose hypometabolism. Overall, this study demonstrated that the degree of brain metabolic abnormality was consistent with clinical seizure severity. In addition, ~SF-FDG PET imaging after treatment was consistent with clinical outcomes. These findings indicate that ~SF-FDG PET can be used to assess the severity of brain injury and prognosis in children with epileptic encephalopathy. 展开更多
关键词 epileptic encephalopathy glucose metabolism fluorine-18 fluoro-2-deoxy-D-glucosepositron emission tomography brain injury PROGNOSIS
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