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Can increased economic complexity and reduced carbon emissions of the logistics industry go hand in hand?Evidence from countries along the Belt and Road

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Advances in Climate Change Research 2023年第5期14卷 789-797页

作者： Chong YE Yan-Hong ZHENG Xiao-Li HAN shi-jun chen School of Advanced Manufacturing Fuzhou UniversityJinjiang 362251China School of Politics and Public Administration Hainan UniveristyHaikou 570228China Chongming Carbon Neutrality Institute Tongji UniversityShanghai 200092China

At present,the main focus of research lies in examining the connection between economic complexity and carbon emissions as a whole,but there is a scarcity of quantitative investigations on the link between the above variables within specific ***,this study introduces economic complexity as a new variable to build a panel model within the traditional Environmental Kuznets Curve *** on the data of the countries along the Belt and Road from 1998 to 2018,we used the Granger causality test to examine the causal relationship between variables,and use the Fully Modified Ordinary Least Square and Dynamic Ordinary Least Square methods to estimate the coefficients of *** key factor linking economic complexity and carbon emissions in the logistics industry is technology innovation Economic complexity can explain and predict the changes in carbon emissions of logistics industry more reasonably,and the relationship between them in line with the environmental kuznets curve *** high-income countries can increase economic complexity while reducing carbon emissions of logistics *** on the empirical analysis,it is suggested that upper-middle income and lower middle-income countries can formulate relevant policies and regulations,and high-income countries can improve the relevant policies and regulations to promote the reduction of carbon emissions of the logistics *** the impact of economic complexity on carbon emissions in the logistics industry can help better predict and respond to the impact of climate change on the logistics industry.

关键词： Economic complexity Carbon emissions of logistics industry Belt and Road countries

Field experiment on train-induced embankment vibration responses in seasonally-frozen regions of Daqing,China

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第8期11卷 596-605页

作者： Xian-zhang LING Li-na WANG Feng ZHANG shi-jun chen Zhan-yuan ZHU School of Civil Engineering Harbin Institute of Technology Harbin 150090 China Institute of Subgrade and Protection Engineering Harbin Institute of Technology Harbin 150090 China Information and Engineering Technology College Sichuan Agricultural University Ya 'an 625014 China

The seasonal-frozen layer may have an influence on embankment motion from train-induced vibrations. Based on the field monitoring in a seasonally-frozen region of northeastern China, the effects of the frozen layer on the embankment responses to train-induced vibration were investigated in winter and summer via acceleration time histories and acceleration frequency spectrums. The results show that: (1) Compared to unfrozen soil conditions, the amplitudes of longitudinal and vertical vibrations at the points near the rail were increased, different influences of freight versus high-speed trains are the most evident. (2) With greater distance from the rail, the dominant frequency ranges of embankment with both frozen and unfrozen layers narrowed and shifted to low frequency bands. (3) The predominant frequency of embankment vibration with frozen soil layers shifted to higher frequencies with the increased train speed, although there was little change with unfrozen condition. Layer condition (frozen versus unfrozen) and distance to rail both play important roles in investigating the embankment vibration characteristics and rail transit field monitoring to improve the criterion of the rail construction in seasonally-frozen regions.

关键词： Embankment vibration Spectrum characteristics Time histories Field monitoring. Seasonally-frozen re^ion

Coexistence and local Mittag–Leffler stability of fractional-order recurrent neural networks with discontinuous activation functions

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Chinese Physics B 2019年第4期28卷 131-140页

作者： Yu-Jiao Huang shi-jun chen Xu-Hua Yang Jie Xiao College of Computer Science and Technology Zhejiang University of Technology

In this paper, coexistence and local Mittag–Leffler stability of fractional-order recurrent neural networks with discontinuous activation functions are addressed. Because of the discontinuity of the activation function, Filippov solution of the neural network is defined. Based on Brouwer's fixed point theorem and definition of Mittag–Leffler stability, sufficient criteria are established to ensure the existence of (2k + 3)~n (k ≥ 1) equilibrium points, among which (k + 2)~n equilibrium points are locally Mittag–Leffler stable. Compared with the existing results, the derived results cover local Mittag–Leffler stability of both fractional-order and integral-order recurrent neural networks. Meanwhile discontinuous networks might have higher storage capacity than the continuous ones. Two numerical examples are elaborated to substantiate the effective of the theoretical results.

关键词： fractional-order recurrent neural network local Mittag–Leffler stability discontinuous activation function

What Can We Learn from the 2008 Melamine Crisis in China?

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Biomedical and Environmental Sciences 2009年第2期22卷 109-111页

作者： jun-shi chen Institute of Nutrition and Food Safety Chinese Center for Disease Control and Prevention Beijing 100050 China

Most food adulterations only cause economic loss and may not necessarily compromise consumer heath. While this may still be a valid argument, the melamine adulterated infant formula crisis in China in 2008 clearly shows that food adulteration could be a serious food safety and public health issue. According to the report by the Ministry of Health of the People＇s Republic of ChinaTM, 294 000 infants and young children in China had been diagnosed to have urinary tract stone by the end of November 2008. Although most patients had no symptoms and signs, acute renal failure did occur in some patients. More than 50 000 infants had been hospitalized with six deaths being confirmed. This food safety crisis not only is a serious issue of the public health but also has a serious impact on the international economy, food trade and even politics. In fact, infant formula from China, no matter which brand, were rejected from importation by many countries; food products other than infant formula from China which contained milk ingredients were also rejected due to the carry-over of melamine from tainted milk. In the Chinese domestic market,

关键词：钙调蛋白结合蛋白质类公共卫生磷蛋白磷酸酶类食品一氧化氮婴儿配方中国铍儿童人类婴儿

Effects of deformation parameters on microstructure and mechanical properties of magnesium alloy AZ31B

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Rare Metals 2006年第z2期25卷 105-110页

作者： ZHANG Shaoming YANG Bicheng XU jun shi Likai chen Guoliang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China General Research Institute for Non-Ferrous Metals Beijing 100088 China General Research Institute for Non-Ferrous Metals Beijing 100088 China General Research Institute for Non-Ferrous Metals Beijing 100088 China General Research Institute for Non-Ferrous Metals Beijing 100088 China State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

Plastic deformation and dynamic recrystallization (DRX) behaviors of magnesium alloy AZ31B during thermal compression and extrusion processes were studied. In addition, effects of deformation temperature and rates on the microstructure and mechanical properties were investigated. The results show that the DRX grains nucleate initially at the primary grain boundaries and the twin boundaries, and the twinning plays an important role in the grain refinement. The DRX grain size depends on the deformation temperature and strain rate The average grain size is only 1 μm when the strain rate is 5 s-1 and temperature is 250 ℃. It is also found that the DRX grain can grow up quickly at the elevated temperature. The microstructure of extruded rods was consisted of tiny equal-axis DRX grains and some elongated grains. The rods extruded slowly have tiny grains and exhibit good mechanical properties.

关键词： magnesium alloy thermal simulation extrusion dynamic recystallization

THE DESIGN OF AN ALL-DIGITAL PHASE-LOCKED LOOP WITH LOW JITTER BASED ON ISF ANALYSIS

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Journal of Electronics(China) 2008年第5期25卷 673-678页

作者： Deng Xiaoying Yang jun shi Longxing chen Xin National ASIC Systems Engineering Technology Research Center Southeast University Nanjing 210005 China

A low jitter All-Digital Phase-Locked Loop （ADPLL） used as a clock generator is designed. The Digital-Controlled Oscillator （DCO） for this ADPLL is a seven-stage ring oscillator with the delay of each stage changeable. Based on the Impulse Sensitivity Function （ISF） analysis, an effective way is proposed to reduce the ADPLL＇s jitter by the careful design of the sizes of the inverters used in the DCO with a simple architecture other than a complex one. The ADPLL is implemented in a 0.18μm CMOS process with *** supply voltage, occupies 0.046mm^2 of on-chip area. According to the measured results, the ADPLL can operate from 108MHz to 304MHz, and the peak-to-peak jitter is 139ps when the DCO＇s output frequency is 188MHz.

关键词： All-Digital Phase Locked Loop (ADPLL) Digital Controlled Oscillator (DCO) Impulse Sensitivity Function (ISF) Thermal noise Jitter

Tea pigments induce cell-cycle arrest and apoptosis in HepG2 cells

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World Journal of Gastroenterology 2005年第34期11卷 5273-5276页

作者： Xu-Dong Jia Chi Han jun-shi chen Institute of Nutrition and Food Safety Chinese center for Disease Control and Prevention 29Nanwei Road Beijing 100050 China

AIM： To investigate the molecular mechanisms by which tea pigments exert preventive effects on liver carcinogenesis. METHODS： HepG2 cells were seeded at a density of 5×10^5/well in six-well culture dishes and incubated overnight. The cells then were treated with various concentrations of tea pigments over 3 d, harvested by trypsinization, and counted using a hemocytometer. Flow cytometric analysis was performed by a flow cytometer after propidium iodide labeling. Bd-2 and p21^WAF1 proteins were determined by Western blotting. In addition, DNA laddering assay was performed on treated and untreated cultured HepG2 cells. RESULTS： Tea pigments inhibited the growth of HepG2 cells in a dose-dependent manner. Flow-cytometric analysis showed that tea pigments arrested cell cycle progression at G1 phase. DNA laddering was used to investigate apoptotic cell death, and the result showed that 100 mg/L of tea pigments caused typical DNA laddering. Our study also showed that tea pigments induced upregulation of p21^WAF1 protein and downregulation of Bcl-2 protein. CONCLUSION： Tea pigments induce cell-cycle arrest and apoptosis. Tea pigments may be used as an ideal chemopreventive agent.

关键词： Tea pigments Cell cycle Apoptosis

Parental awareness on myopia prevention and control among 350 children

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International Journal of Ophthalmology(English edition) 2024年第11期17卷 2109-2119页

作者： Tian-Tian Li Zi-Shui Fang Yu-Xin Xue shi-jun chen Ying-Xin Yang Tie-jun Li Yue Yang Yan Wu Department of Ophthalmology Beijing Hospital of Traditional Chinese MedicineBeijing 100010China Department of Urology Peking University First HospitalBeijing 100034China Beijing University of Chinese Medicine Beijing 100029China

AIM:To understand the current situation of parental perspectives,knowledge,and practices concerning myopia prevention and control for both pre-and school-aged ***:This study was a cross-sectional survey that involved children aged 0 to 15y and their *** were required to respond to an online questionnaire by scanning a quick response(QR)*** questionnaire consisted of 25 tick-box questions and was open to response from December 22,2022,to January 5,*** dioptric traits of the children,the visual status and educational background of the parents,the parental perspectives towards myopia and its risks,and the parents’knowledge and practices related to myopia prevention and control were recorded and *** Chi-square test and binomial logistic regression were used for ***:Totally 350 parents responded to the *** prevalence and severity of myopia among the surveyed children exhibited a positive correlation with advancing age(P<0.001 and P=0.004,respectively).Nearly half of parents with myopic children considered myopia did not pose any health threat and could be effectively corrected(P<0.001).Parents who held master’s or doctoral degree demonstrated a better understanding of children’s vision standards for each age group(P=0.001),and 31.63% of them could undergo initial vision screening for their children during the age of 0 to 3y while parents with bachelor’s degree(34.04%)and below(32.43%)mainly initiated the vision examination for their children at the age of 4 to 6y(P=0.05).Parents with master’s or doctoral degree also exhibited more rational practices concerning outdoor time(P=0.048)and sleep time(P=0.044).No other significant discrepancy among the different educational groups in additional conceptions of myopia,such as hyperopia reserve,axis length,and corneal curvature *** parents preferred to employ conventional interventions,such as enhancing indoor lighting condition(80.00%)and

关键词： myopia myopia prevention and control parental perspectives pre-and school-aged children

Efficacy of Different Iron Fortificants in Wheat Flour in Controlling Iron Deficiency

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Biomedical and Environmental Sciences 2009年第2期22卷 118-121页

作者： JIAN HUANG JING SUN WEN-XIAN LI LI-JUAN WANG AN-Xu WANG jun-SHENG HUO jun-shi chen AND CHUN-MING chen Institute of Nutrition and Food Safety Chinese Center for Disease Control and Prevention Beijing 100050 China Nanyang Wancheng District Center of Disease Control and Prevention Nanyang 473009 Henan China

Objective To observe the different impacts of electrolytic iron, FeSO4, and NaFeEDTA on body iron store of anemic school students. Methods Four hundreds anemic students at the age of 11-18 years were divided into four groups. Of which, three consumed different iron fortificants from wheat flour as food vehicle for six months and one consumed non-fortified flour （control）. The fortification level of electrolytic iron, FeSO4, and NaFeEDTA was 60 mg Fe/kg, 30 mg Fe/kg, and 20 mg Fe/kg, respectively. Blood samples were collected at 0, 2, 4, and 6 months and hemoglobin （Hb）, serum ferritin （SF）, and transferrin receptor （TfR） were measured. Results The hemoglobin levels in three intervention groups increased, the increments of Hb in the NaFeEDTA group were significantly higher than that in the other groups. SF and TfR levels increased in the tested groups and body iron store in the NaFeEDTA group was higher than that in the other groups. These parameters did not show any significant changes in the control group. Conclusion NaFeEDTA and FeSO4 tortified wheat flour has positive impacts on iron status in anemic students and NaFeEDTA is more effective than FeSO4, while electrolytic iron is less effective in improving iron store in anemic students.

关键词： Body iron Iron deficiency anemia Wheat flour Fortification Electrolytic iron FeSO4 NaFeEDTA