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REAL EFFECTS & DIVERSITY TO BE STRESSED IN INTERNATIONAL COOPERATION
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作者 Zheng Chongzhi and Mao Guoqing(Shanghai Institute of Organic Chemistry, CAS) 《Bulletin of the Chinese Academy of Sciences》 1997年第1期88-90,共3页
In recent years, the Shanghai Institute of Organic Chemistry under the CAS has freed itself from the stereotyped rut of conventional forms in its external intercourse while still sticking fast to upholding its strateg... In recent years, the Shanghai Institute of Organic Chemistry under the CAS has freed itself from the stereotyped rut of conventional forms in its external intercourse while still sticking fast to upholding its strategic goal of disciplinary development. Our stress in this aspect has shifted to the pursuit of real effects and diversified forms in international S&T exchange. Our exploration features the following four characteristics: 展开更多
关键词 DIVERSITY TO BE STRESSED IN INTERNATIONAL COOPERATION real effectS CAS US BE
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Real Effective Exchange Rate and Regional Economic Growth in China: Evidence from Provincial Data 被引量:3
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作者 Guo Yan Sheng Li +1 位作者 Yaqi Lin Jie Li 《China & World Economy》 SCIE 2016年第6期43-63,共21页
Using data for the period 2000-2011, we construct province-level real effective exchange rate (REER) indices for China and test the effect of REER depreciation on regional economic growth in a generalized method of ... Using data for the period 2000-2011, we construct province-level real effective exchange rate (REER) indices for China and test the effect of REER depreciation on regional economic growth in a generalized method of moments regression framework. Our results show that REER depreciation, in general, promotes regional economic growth, through increasing net exports and lowering FDI costs. After dividing the full sample into coastal and inland subsamples, we find that REER depreciation influences economic growth in inland areas but not in coastal areas. This is due to the fact that the inland areas have more surplus labor or other resources to expand their production capacity when REER depreciation leads to increased worm demand. Furthermore, compared to inland areas, processing-and-assembly trade comprises a larger share of trade in the coastal areas, where traders import more raw materials and intermediate goods to process and assemble goods. When the exchange rate depreciates, the costs of imported materials and immediate goods increase. In this case, the benefits from REER depreciation in coastal areas are offset to some extent and are thus lower than in inland areas. 展开更多
关键词 China real effective exchange rate regional economic growth
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Industry-specific Real Effective Exchange Rate for China:2000-2009 被引量:1
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作者 Mi Dai Jianwei Xu Zhinan Zhang 《China & World Economy》 SCIE 2013年第5期100-120,共21页
This paper measures the industry-specific real effective exchange rate (REER) for China by matching domestic and foreign industry-level price and trade data series. We find that after 2005 the REER appreciates more ... This paper measures the industry-specific real effective exchange rate (REER) for China by matching domestic and foreign industry-level price and trade data series. We find that after 2005 the REER appreciates more in the "chemical, plastics, rubber and fuels industry" and the "'machinery and equipment industry," but remains roughly constant or even depreciates in other industries. The nominal exchange rate generally accounts for over 50 percent of the aggregate real effective exchange rate JTuetuations, but this conclusion does not apply to three of nine industries. We apply the industry-specific REER to re-examine the relationship between the exchange rate and trade, and find that the industry-specific REER index performs better than the traditional aggregate REER index. We recommend that the Chinese Government officially adopt industry-specific exchange rates instead of using the aggregate effective exchange rates to evaluate the competitiveness of Chinese industries in the international market. 展开更多
关键词 China INDUSTRY real effective exchange rate TRADE
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Real effects of greenhouse gas disclosures
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作者 Tong Lu Lijun Ruan +1 位作者 Yanyan Wang Lisheng Yu 《China Journal of Accounting Research》 2024年第2期31-53,共23页
This study investigates the valuation and real effects of the mandatory disclosure of greenhouse gas(GHG)emission costs from the perspective of“double materiality.”We consider a firm with a Cobb-Douglas production f... This study investigates the valuation and real effects of the mandatory disclosure of greenhouse gas(GHG)emission costs from the perspective of“double materiality.”We consider a firm with a Cobb-Douglas production function that combines GHG-related and non-GHG-related investments to produce short-term and long-term returns.In particular,the GHG-related investment entails short-term and long-term social costs of GHG emissions,including corporate costs and negative externalities.We demonstrate how the mandatory disclosure of the long-term costs of GHG emissions affects capital market valuations and corporate investment decisions relative to a non-disclosure regime.The social welfare in an accounting regime hinges on three parameters:the persistence of the short-term investment return,the ratio of the productivity of GHG-related investment to that of non-GHG-related investment,and the social cost parameter for GHG emissions.Our findings suggest that disclosing the long-term costs of GHG emissions may be detrimental to social welfare.Specifically,the non-disclosure regime results in higher social welfare than the disclosure regime for high values of these parameters. 展开更多
关键词 Greenhouse gas emissions EXTERNALITY Double materiality DISCLOSURE real effects
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Real Gas Effects on Charging and Discharging Processes of High Pressure Pneumatics 被引量:7
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作者 LUO Yuxi WANG Xuanyin GE Yaozheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第1期61-68,共8页
The high pressure pneumatic system has been applied to special industries. It may cause errors when we analyze high pressure pneumatics under ideal gas assumption. However, the real gas effect on the performances of h... The high pressure pneumatic system has been applied to special industries. It may cause errors when we analyze high pressure pneumatics under ideal gas assumption. However, the real gas effect on the performances of high pressure pneumatics is seldom investigated. In this paper, the real gas effects on air enthalpy and internal energy are estimated firstly to study the real gas effect on the energy conversion. Under ideal gas assumption, enthalpy and internal energy are solely related to air temperature. The estimation result indicates that the pressure enthalpy and pressure internal energy of real pneumatic air obviously decrease the values of enthalpy and internal energy for high pressure pneumatics, and the values of pressure enthalpy and pressure internal energy are close. Based on the relationship among pressure, enthalpy and internal energy, the real gas effects on charging and discharging processes of high pressure pneumatics are estimated, which indicates that the real gas effect accelerates the temperature and pressure decreasing rates during discharging process, and decelerates their increasing rates during charging process. According to the above analysis, and for the inconvenience in building the simulation model for real gas and the difficulty of measuring the detail thermal capacities of pneumatics, a method to compensate the real gas effect under ideal gas assumption is proposed by modulating the thermal capacity of the pneumatic container in simulation. The experiments of switching expansion reduction (SER) for high pressure pneumatics are used to verify this compensating method. SER includes the discharging process of supply tanks and the charging process of expansion tank. The simulated and experimental results of SER are highly consistent. The proposed compensation method provides a convenient way to obtain more realistic simulation results for high pressure pneumatics. 展开更多
关键词 real gas effect pneumatic simulation model high pressure pneumatics
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Real world effectiveness of PCSK-9 inhibitors combined with statins versus statins-based therapy among patients with very high risk of atherosclerotic cardiovascular disease in China(RWE-PCSK study) 被引量:8
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作者 Yu-Qi LIU Dan-Dan LI +32 位作者 Meng CHAI Hong-Liang CONG Xiao-Qiang CONG Jun DAI Rong-Pin DU Ming GAO Jin-Cheng GUO Yan-Qing GUO Xiao-Jian HONG Rong-Chong HUANG Feng-Shun JIA Jia-Yu LI Qing LI Jia-Mei LIU Xin-Ping LIU Yu-Guo LIU Hong-Gang NIE Bing SHAO Xiao-Yu SHEN Hai-Qing SONG Yi-Jun SONG Li-Jun WANG Shuo WANG Dong-Mei WU Jing XIA Zhi-Yong YANG Hong-Ying YU Hui ZHANG Tie-Mei ZHANG Ji-Yi ZHAO Liang-Chen ZHAO Ming-Qi ZHENG Yun-Dai CHEN 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2021年第4期261-270,共10页
BACKGROUND The efficacy and safety of proprotein convertase subtilisin/kexin type 9(PCSK-9) inhibitors were confirmed by several clinical trials, but its effectiveness in routine clinical practice in China has not bee... BACKGROUND The efficacy and safety of proprotein convertase subtilisin/kexin type 9(PCSK-9) inhibitors were confirmed by several clinical trials, but its effectiveness in routine clinical practice in China has not been evaluated. This study aims to describe the real world effectiveness of PCSK-9 inhibitors combined with statins compared with statins-based therapy among patients with very high risk of atherosclerotic cardiovascular disease(ASCVD).METHODS This is a multi-center observational study, enrolled patients from 32 hospitals who underwent percutaneous coronary intervention(PCI) from January to June in 2019. There are 453 patients treated with PCSK-9 inhibitors combined with statins in PCSK-9 inhibitor group and 2,610 patients treated with statins-based lipid lowering therapies in statins-based group. The lipid control rate and incidence of major adverse cardiovascular events(MACE) over six months were compared between two groups.A propensity score-matched(PSM) analysis was used to balance two groups on confounding factors. Survival analysis using Kaplan-Meier methods was applied for MACE.RESULTS In a total of 3,063 patients, 89.91% of patients had received moderate or high-intensity statins-based therapy before PCI, but only 9.47% of patients had low-density lipoprotein cholesterol(LDL-C) levels below 1.4 mmol/L at baseline. In the PSM selected patients, LDL-C level was reduced by 42.57% in PCSK-9 inhibitor group and 30.81%(P < 0.001) in statins-based group after six months. The proportion of LDL-C ≤ 1.0 mmol/L increased from 5.29% to 29.26% in PCSK-9 inhibitor group and 0.23% to 6.11% in statins-based group, and the proportion of LDL-C ≤ 1.4 mmol/L increased from 10.36% to 47.69% in PCSK-9 inhibitor group and 2.99% to 18.43% in statins-based group(P < 0.001 for both). There was no significant difference between PCSK-9 inhibitor and statins-based treatment in reducing the risk of MACE(hazard ratio = 2.52, 95% CI: 0.49-12.97, P = 0.250).CONCLUSIONS In the real world, PCSK-9 inhibitors combined with statins could significantly reduce LDL-C levels among patients with very high risk of ASCVD in China. The long-term clinical benefits for patients received PCSK-9 inhibitor to reduce the risk of MACE is still unclear and requires further study. 展开更多
关键词 LDL RWE-PCSK study real world effectiveness of PCSK-9 inhibitors combined with statins versus statins-based therapy among patients with very high r
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Simulation and experimental study of high pressure switching expansion reduction considering real gas effect 被引量:2
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作者 罗语溪 张彦军 +2 位作者 高玉宝 王宣银 徐志鹏 《Journal of Central South University》 SCIE EI CAS 2014年第6期2253-2261,共9页
Switching expansion reduction(SER)uses a switch valve instead of the throttle valve to realize electronically controlled pressure reduction for high pressure pneumatics.A comprehensive and interactive pneumatic simula... Switching expansion reduction(SER)uses a switch valve instead of the throttle valve to realize electronically controlled pressure reduction for high pressure pneumatics.A comprehensive and interactive pneumatic simulation model according to the experimental setup of SER has been built.The mathematical model considers heat exchanges,source air pressure and temperature,environmental temperatures and heat transfer coefficients variations.In addition,the compensation for real gas effect is used in the model building.The comparison between experiments and simulations of SER indicates that,to compensate the real gas effect in high pressure discharging process,the thermal capacity of air supply container in simulation should be less than the actual value.The higher the pressure range,the greater the deviation.Simulated and experimental results are highly consistent within pressure reduction ratios ranging from 1.4 to 20 and output air mass flow rates ranging from 3.5 to 132 g/s,which verifies the high adaptability of SER and the validity of the mathematic model and the compensation method. 展开更多
关键词 high pressure pneumatics pressure reduction dynamic simulation model real gas effect
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Compensation of Pressure Enthalpy Effects on Temperature Fields for Throttling of High-Pressure Real Gas
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作者 罗语溪 梁九兴 +1 位作者 王宣银 徐志鹏 《Journal of Shanghai Jiaotong university(Science)》 EI 2017年第2期216-223,共8页
For the pressure enthalpy of high pressure pneumatics, the computational fluid dynamics (CFD) simulation based on ideal gas assumption fails to obtain the real temperature information. Therefore, we propose a method t... For the pressure enthalpy of high pressure pneumatics, the computational fluid dynamics (CFD) simulation based on ideal gas assumption fails to obtain the real temperature information. Therefore, we propose a method to compensate the pressure enthalpy of throttling for CFD simulation based on ideal gas assumption. Firstly, the pressure enthalpy is calculated for the pressure range of 0.101 to 30 MPa and the temperature range of 190 to 298 K based on Soave-Redlich-Kwong (S-R-K) equation. Then, a polynomial fitting equation is applied to practical application in the above mentioned range. The basic idea of the compensation method is to convert the pressure enthalpy difference between inlet air and nodes into the compensation temperature. In the above temperature and pressure range, the compensated temperature is close to the real one, and the relative temperature drop error is below 10%. This error is mainly caused by the velocity difference of the orifice between the real and ideal gas models. Finally, this compensation method performs an icing analysis for practical high pressure slide pilot valve. © 2017, Shanghai Jiaotong University and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 real gas effect pressure enthalpy temperature field throttling computational fluid dynamics(CFD) Soave-Redlich-Kwong(S-R-K) equation
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Efficient flow stability analysis method for real gas
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作者 Ruiyang LU Zhangfeng HUANG 《Chinese Journal of Aeronautics》 2025年第12期91-105,共15页
Transitions within the boundary layer significantly affect the aerodynamic and aerothermodynamic dynamics of hypersonic vehicles.Accurately predicting these transitions poses a significant challenge in vehicle design.... Transitions within the boundary layer significantly affect the aerodynamic and aerothermodynamic dynamics of hypersonic vehicles.Accurately predicting these transitions poses a significant challenge in vehicle design.At high speeds and altitudes,thermochemical processes within the hypersonic boundary layer lead to real gas effects that alter flow stability and further complicate transition prediction.Direct numerical simulation and linear stability theory are used to investigate the effects of chemical reaction-induced terms on the second and cross-flow modes,and to identify the main sources of species disturbances.Efficient stability analysis method for real gas is developed by applying multilevel assumptions to the linear stability equation.The results indicate that at lower wall temperatures,species disturbances primarily arise from convective terms,and there is a continuous contribution from chemical reaction source terms.The contributions of the diffusion and chemical source terms to species disturbances increase with the intensity of chemical reactions.When the nitrogen within the boundary layer is not dissociated or is only weakly dissociated,the assumption of complete freezing of the species disturbances can be employed to enhance the computational efficiency of the linear stability analysis.Chemical non-equilibrium linear stability theory based on the freezing assumption is suitable for most experimental and flight conditions,significantly reducing the computational time for real gas transition predictions,making it comparable to that for perfect gas. 展开更多
关键词 Hypersonic boundary layer Linear stability analysis Nonequilibrium flow real gas effect Transition prediction
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中医穴位贴敷治疗腹泻回顾性队列研究
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作者 李庆娜 蒋艳文 +17 位作者 主佳旭 郭曼萍 王一名 栗蕊 陈海涛 郭建 甘文帆 牛粉玲 雷激光 李清霄 苏磊 陈洋 石玉来 谢继瑞 朱明波 靳韬 陆芳 高蕊 《中国中西医结合杂志》 北大核心 2026年第1期25-32,共8页
目的探讨中医穴位贴敷治疗腹泻的有效性及有效人群特征、贴敷处方特点。方法采用回顾性队列研究方法,基于互联网诊疗平台2022年5月—2023年5月的腹泻病例资料,按是否使用穴位贴敷治疗分为暴露组(贴敷组)和非暴露组(非贴敷组)。采用倾向... 目的探讨中医穴位贴敷治疗腹泻的有效性及有效人群特征、贴敷处方特点。方法采用回顾性队列研究方法,基于互联网诊疗平台2022年5月—2023年5月的腹泻病例资料,按是否使用穴位贴敷治疗分为暴露组(贴敷组)和非暴露组(非贴敷组)。采用倾向性评分匹配(PSM)调整年龄、性别等混杂因素,以治疗1、2、3天腹泻消失率为疗效观察指标,采用多因素回归分析评估疗效,并利用关联规则分析有效人群特征及处方规律。结果PSM后贴敷组3012例,非贴敷组1593例,贴敷组治疗1、2天腹泻消失率优于非贴敷组(P<0.001),OR分别为1.933(1.623~2.304)、1.507(1.321~1.718),中位消失时间更短(2.333 vs.3.042天,χ^(2)=43.874,P<0.001)。多因素回归分析显示,治疗1、2、3天腹泻消失率贴敷组均优于非贴敷组(P<0.001),OR分别为2.028(95%CI:1.639~2.510)、1.744(95%CI:1.480~2.055)及1.395(95%CI:1.197~1.627)。分层分析与交互作用检验显示,是否使用抗生素以及其他腹泻药物两个因素与暴露因素间有明显的交互作用(P<0.001),仅在不合并使用抗生素或其他腹泻药物时,贴敷组疗效优于非贴敷组(P<0.001)。使用中医穴位贴敷治疗的有效病例10803例,其中3岁以下婴幼儿占比最高,常用的贴敷穴位包括神阙、中脘、大椎、涌泉等,其中最常联用的穴位是中脘和神阙,支持度为58.42%;常用的贴敷药物包括黄连、芒硝、吴茱萸、藿香等,其中黄连最常贴敷于神阙穴,支持度为33.33%。结论中医穴位贴敷治疗腹泻有效,且单独应用相较联合用药可能具有一定优势,神阙与黄连分别为最常用的穴位和药物。 展开更多
关键词 腹泻 穴位贴敷 中医药 有效性 贴敷处方 回顾性队列研究 真实世界研究
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真实气体效应下飞行/喷流参数对逆向喷流减阻降热特性的影响
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作者 杜佳宝 吴锦水 段润泽 《空气动力学学报》 北大核心 2026年第1期96-108,共13页
高速飞行器飞行时会产生大量的气动阻力和气动热,周围气体分子的振动能和电子能被激发,并发生离解和电离等化学反应,真实气体效应不可忽略。逆向喷流技术作为一种主动热防护技术,已受到广泛关注,因此有必要对真实气体效应下的逆向喷流... 高速飞行器飞行时会产生大量的气动阻力和气动热,周围气体分子的振动能和电子能被激发,并发生离解和电离等化学反应,真实气体效应不可忽略。逆向喷流技术作为一种主动热防护技术,已受到广泛关注,因此有必要对真实气体效应下的逆向喷流减阻降热特性进行深入研究。本文基于数值计算方法,对比了不同气体模型下逆向喷流系统的性能,发现热化学非平衡气体模型对钝体阻力与热流的预测更为准确,更适用于高速飞行器的气动热环境分析。采用二维可压缩Navier-Stokes方程和热化学非平衡气体模型模拟了钝体在不同飞行条件下喷流系统的流场分布,研究了真实气体效应下飞行/喷流参数对喷流流场结构、钝体气动阻力和气动热的影响。结果表明:飞行马赫数增大,钝体的总阻力和总热流显著增加,飞行马赫数从8增大到12,钝体的总阻力系数提高了29.30%,总热流增大了8.53倍。飞行攻角为10°时,迎风面和背风面的壁面压力相差2.57倍,最大热流密度相差16.17倍。增大飞行高度会降低来流总压,使喷流穿透能力增强,飞行高度从32 km增加到36 km,钝体峰值压力降低了36.34 kPa,峰值热流密度降低了1.32 MW/m_(2)。增大喷流压比对降低钝体总阻力和总热流具有显著效果,当喷流压比为0.014时,系统减阻降热效果最佳,总阻力系数和总热流相较无喷流时分别降低41.32%和73.55%。喷流温度变化主要影响近壁面温度分布,温度升高虽对钝体总阻力系数影响甚微,但会提高钝体总热流,导致系统减阻降热效率降低。 展开更多
关键词 逆向喷流 真实气体效应 减阻 降热 热化学非平衡气体模型 热防护
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“双碳”目标下数实融合的绿色赋能效应——基于政府与市场视角的分析
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作者 张治栋 丁世杰 《天津商业大学学报》 2026年第1期55-63,共9页
基于2011—2022年的城市面板数据,构建了双向固定效应模型以检验数实融合的绿色赋能效应。研究结果表明:数实融合能够促进城市绿色技术创新“量质并举”,主要通过增加财政科技支出和发挥人力资本效应来实现,且数实融合所产生的绿色赋能... 基于2011—2022年的城市面板数据,构建了双向固定效应模型以检验数实融合的绿色赋能效应。研究结果表明:数实融合能够促进城市绿色技术创新“量质并举”,主要通过增加财政科技支出和发挥人力资本效应来实现,且数实融合所产生的绿色赋能效应具有边际递增的非线性特征;异质性分析发现,在重点城市、非资源型城市和高市场竞争水平城市中,数实融合对城市绿色技术创新的促进效应更为显著;此外,市场竞争能够正向调节数实融合对城市绿色技术创新的影响效果。据此提出加大数字基础设施建设投资力度等政策建议。 展开更多
关键词 数实融合 城市绿色技术创新 门槛模型 调节效应
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Analysis of the Moderator Effect of RMB Exchange-- Rate on Export The Case of Guangdong Province in China
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作者 Yan Zhang Yan Zhou Haojia Chen 《Economics World》 2017年第3期281-286,共6页
An important limitation of the research literatures which study the effect on the export of the real effective exchange rates is the lack of application of interaction or moderator effect among the independent variabl... An important limitation of the research literatures which study the effect on the export of the real effective exchange rates is the lack of application of interaction or moderator effect among the independent variables. To remedy this lacuna, the authors developed a model in which real effective exchange rate moderated the effect of import and utilization of foreign capital on export. The sample comprised 11 years' data in Guangdong China. The result showed that real effective exchange rate of RMB affected the export by interacting with utilization of foreign capital. Moreover, to some degree, the real effective exchange rate can also act as moderator between import and export. 展开更多
关键词 IMPORT EXPORT real effective exchange rate (REER) utilization of foreign capital moderator effect
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利用Real-time PCR对4个转Bt基因水稻的非预期效应研究 被引量:1
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作者 孙玥 王春雷 +5 位作者 欧阳林娟 周大虎 傅军如 朱昌兰 贺浩华 彭小松 《核农学报》 CAS CSCD 北大核心 2018年第11期2107-2118,共12页
转基因水稻中外源基因的转入可能会形成新的代谢产物,造成农艺性状的改变等,这些均不利于农业生产的非预期效应。为探究转基因水稻是否存在非预期效应,本研究以江西农业大学选育的4个转Bt基因恢复系为试验材料,通过反向PCR扩增侧翼序列... 转基因水稻中外源基因的转入可能会形成新的代谢产物,造成农艺性状的改变等,这些均不利于农业生产的非预期效应。为探究转基因水稻是否存在非预期效应,本研究以江西农业大学选育的4个转Bt基因恢复系为试验材料,通过反向PCR扩增侧翼序列并比对,用216对SSR引物对供试材料进行全基因组背景分析,再以Real-time PCR检测外源基因插入位点上下游100 kb内所有基因表达差异,并对光合色素含量及9个主要农艺性状进行显著性分析。结果表明,cry1C侧翼序列片段大小为1 276bp,定位在水稻第11号染色体上,cry2A侧翼序列片段大小为948 bp,定位在水稻第12号染色体上;昌恢121T、昌恢891T、昌恢T025T、R205选T的遗传背景回复率分别为95.60%、88.43%、93.52%、94.44%;基因表达分析显示试验组和对照组在cry1C、cry2A插入位置上下游100 kb内所有侧翼基因的表达水平均无显著性差异;进一步调查发现,试验组和对照组的光合色素含量及9个农艺性状无显著性差异。综上,cry1C和cry2A插入水稻基因组没有改变侧翼100 kb内基因表达水平,且4个转基因水稻并未产生非预期效应。本研究结果为探究转基因水稻的非预期效应评价提供了一定的理论参考。 展开更多
关键词 转基因水稻 非预期效应 real-TIME PCR 侧翼序列 遗传背景回复率
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国内外心力衰竭治疗药物经济学研究的差异比较
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作者 申锐加 杨晓彧 +2 位作者 孙德锋 李伟娅 赵振营 《中国药房》 北大核心 2026年第5期626-632,共7页
目的为我国心力衰竭治疗药物经济学研究接轨国际提供依据。方法定性比较国内外心力衰竭药物经济学研究在研究方法与模型应用、研究视角与终点指标、数据来源与参数选择、政策转化与实践影响四方面的差异。结果与结论国外研究多采用长期... 目的为我国心力衰竭治疗药物经济学研究接轨国际提供依据。方法定性比较国内外心力衰竭药物经济学研究在研究方法与模型应用、研究视角与终点指标、数据来源与参数选择、政策转化与实践影响四方面的差异。结果与结论国外研究多采用长期动态模型、全社会视角、真实世界数据融合并直接支撑医保决策;国内研究多偏短期简化分析、采用卫生体系单一视角、依赖文献数据且多限于个体用药建议。建议国内研究向长周期动态建模转型,依托大数据构建本土专病效用数据库,建立与医保挂钩的闭环机制,并深化多学科协作,以优化医疗资源配置。 展开更多
关键词 心力衰竭治疗药物 药物经济学研究 国际经验 成本-效果分析 成本-效用分析 真实世界数据 本土化 医保决策
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建成环境对房产价值的非线性效应研究——以天津市为例
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作者 陈飞扬 蔡军 +1 位作者 杨琪瑶 丁梦真 《建筑与文化》 2026年第2期56-58,共3页
深入认识建成环境对房价的影响,对于制定合理的房价与城市更新政策至关重要。既有研究大多关注建成环境对房价的线性影响,而忽略了其非线性效应。文章以天津为例,运用多源大数据,借助随机森林和SHAP模型,剖析建成环境与房价之间的非线... 深入认识建成环境对房价的影响,对于制定合理的房价与城市更新政策至关重要。既有研究大多关注建成环境对房价的线性影响,而忽略了其非线性效应。文章以天津为例,运用多源大数据,借助随机森林和SHAP模型,剖析建成环境与房价之间的非线性关系及阈值效应,研究发现:(1)教育资源是导致房价差异的最关键因素;(2)建成环境要素对房价的影响呈现非线性效应,合理配置这些要素能够有效提升房价;(3)建成环境要素的配置应考虑其交互效应;(4)区域过度商业化会致使房价下跌。相关分析结果可为房产价值研究提供理论参考。 展开更多
关键词 建成环境 房产价值 多源数据 机器学习 非线性效应
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基于广域电磁法的压裂暂堵参数实时优化应用
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作者 王导丽 李爱勇 +6 位作者 詹少全 李鹏昆 武伟 洪昊 裴英峰 吕姗姗 陈艺竹 《工程地球物理学报》 2026年第1期147-154,共8页
压裂暂堵效果在非常规油气藏的体积压裂技术中至关重要,加强实时监测是提高压裂效果的关键研究方向和应用重点。广域电磁法作为有源电磁法技术,通过发射A极和接收N极与井筒直接相连,发射伪随机信号获得了稳定可靠的电场信号,从而获得压... 压裂暂堵效果在非常规油气藏的体积压裂技术中至关重要,加强实时监测是提高压裂效果的关键研究方向和应用重点。广域电磁法作为有源电磁法技术,通过发射A极和接收N极与井筒直接相连,发射伪随机信号获得了稳定可靠的电场信号,从而获得压裂液波及形态等信息。本文在某页岩油井体积压裂时开展了广域电磁法实时压裂监测应用,通过地面接收电场信号的变化进行时间域实时差分计算,对其差分异常采用深度约束反演技术,定量计算压裂液波及的方向、范围等实时几何形态信息。在暂堵施工实践中优化暂堵时机、指导暂堵参数优化和暂堵效果评价等方面取得了显著的应用效果。对降低暂堵风险、评价暂堵效果、改进暂堵工艺和压裂设计等提供了技术支撑,具有一定的指导意义。 展开更多
关键词 广域电磁法 裂缝改造 实时 压裂监测 暂堵 效果评价
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FDI's real impact on foreign exchange reserves:Evidence from China
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作者 孙文凯 梅松 《China Economist》 2009年第5期74-78,共5页
Most scholars believe that FDI inflow has a direct impact on China’s foreign exchange reserve,while others hold that FDI is mainly invested in the form of physical capital and technology,and therefore does not direct... Most scholars believe that FDI inflow has a direct impact on China’s foreign exchange reserve,while others hold that FDI is mainly invested in the form of physical capital and technology,and therefore does not directly contribute to China’s foreign exchanges reserve accumulation.This paper points out that both effects,direct and indirect,should be considered when assessing FDI’s contribution to foreign exchange reserves.Result shows that from 1986 to 2007,FDI contributed 50%to foreign exchange reserves and the direct effect dominant before 2003 was surpassed by indirect effect after 2001 as the major source of the contribution. 展开更多
关键词 FDI FOREIGN EXCHANGE RESERVES real effect
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数字化监管的实体经济效应:基于投资效率的证据 被引量:2
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作者 陈运森 张颖 马宇航 《经济理论与经济管理》 北大核心 2025年第4期56-75,共20页
探索数字化监管的实体经济效应对防范化解重大风险、促进实体经济高质量发展具有重要意义。基于地方证监局差异化应用数字化监管系统的独特场景,本文考察了数字化监管对上市公司投资效率的影响。研究发现,地方证监局应用数字化监管系统... 探索数字化监管的实体经济效应对防范化解重大风险、促进实体经济高质量发展具有重要意义。基于地方证监局差异化应用数字化监管系统的独特场景,本文考察了数字化监管对上市公司投资效率的影响。研究发现,地方证监局应用数字化监管系统后,辖区内上市公司的投资效率显著提升。机制分析表明,提高信息披露质量和抑制管理层机会主义行为是数字化监管发挥作用的潜在渠道。异质性分析发现,对经营风险更高、治理风险更高以及市场风险更高的公司,数字化监管提升投资效率的作用更明显。进一步研究表明,数字化监管还显著提升了企业创新投入水平。本文为推动数字化监管建设、提高资本市场服务实体经济能力提供了重要启示。 展开更多
关键词 数字化监管 实体经济效应 投资效率 资本市场监管
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考虑真实效应的旋转爆震波动力学 被引量:1
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作者 王兵 秦文楷 +4 位作者 闻浩诚 师迎晨 范文琦 罗发轩 李子栋 《火箭推进》 北大核心 2025年第3期77-102,共26页
旋转爆震波在传播过程中受到一系列真实效应的制约,使得旋转爆震波的动力学特性发生显著变化。按产生来源不同,真实效应可归类为真实边界约束和非理想物理过程两种。真实边界约束可视为旋转爆震波传播的空间条件,对于燃烧室而言,约束主... 旋转爆震波在传播过程中受到一系列真实效应的制约,使得旋转爆震波的动力学特性发生显著变化。按产生来源不同,真实效应可归类为真实边界约束和非理想物理过程两种。真实边界约束可视为旋转爆震波传播的空间条件,对于燃烧室而言,约束主要来自喷注、燃烧室几何和燃烧室上下游部件。这些约束会使受限空间内的旋转爆震波的结构产生横向畸变,诱发熄爆等动态过程,或产生部件间的不匹配现象。非理想物理过程来自流动与燃烧过程的内禀属性,诱使旋转爆震波产生更多不同尺度释热和流动结构,如次级燃烧等。若这类过程具有明显的非线性动力学特征,如波的分岔和聚并,则会对旋转爆震波的传播特性产生影响,进而对发动机的推进性能构成挑战。对相关研究前沿进行梳理,指出考虑真实效应时的旋转爆震波传播特性仍未被充分理解,且定量表征匮乏。目前大量研究聚焦于特定发动机构型,缺乏统一的旋转爆震波系结构描述和发动机性能评估框架,且实验测量的时空分辨率仍有待提高。 展开更多
关键词 旋转爆震波 真实效应 喷注 次级燃烧 激波
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