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Direct Visual Evidence for Neutral and Charged Hexaphyrin Aromaticity with and without Keto-Defect

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Chinese Journal of Chemical Physics 2012年第5期25卷 563-570,I0003页

作者： Shan Zhang Peng Song Sha Wang Yu-ling Chu yuan-zuo li zhong Yang Yong ding feng-cai Ma Department of Physics Liaoning UniversityShenyang 110036China Physical and Electronic and Information Engineering Institute Chifeng UniversityChifeng 024001China College of Science Northeast Forestry UniversityHarbin 150040China

We use density functional theory and time-dependent together with a set of extensive mul- tidimensional visualization techniques to characterize the influence of keto effect on charge distribution at ground state and electronic transitions for neutral and charged hexaphyrin aromaticity with and without keto-defect. It is found that the aromaticity is the key fac- tor to influence the ground state Mulliken charges distribution properties, other than the meso-aryl-substituted effect. But with the enhancement of the keto-defect, the distribution changes of Mulliken charges on the hexaphyrin groups are larger than those on the pentaflu- orophenyl substituted groups, following with the aromaticity changes from nonaromatic to aromatic. Furthermore, through characterizing by transition density and charge difference density, direct visual evidence for neutral and charged aromaticity with and without keto- defect can be clearly derived, and the ability of charge transfer between units of monoradical （nonaromaticity） and singlet biradical （aromaticity） forms is much stronger than that of neutral forms.

关键词： Aromaticity Keto-defect Porphyrin Charge difference density Transitiondensity

Association between Mean Ocular Perfusion Pressure and Diabetic Retinopathy in a Northeastern Chinese Population

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Biomedical and Environmental Sciences 2020年第9期33卷 701-707页

作者： ZHAI Gang liN zhong WANG feng Hua WANG Yu li Dong WEN liang ding Xiao Xia JIANG Jing feng Ke Mi liANG yuan Bo XIE Cong Fushun Eye Hospital Fushun 113006LiaoningChina School of Ophthalmology&Optometry Wenzhou Medical UniversityEye Hospital of Wenzhou Medical UniversityWenzhou 325035ZhejiangChina Beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical UniversityBeijing Ophthalmology&Visual Science Key LabBeijing 100730China

Objective To evaluate the association between diabetic retinopathy(DR) and mean ocular perfusion pressure(MOPP) in patients with type 2 diabetes mellitus(T2 DM).Methods Patients from the Fushun Diabetic Retinopathy Cohort Study(FS-DIRECT), a communitybased prospective cohort study conducted in northeast China, were included in this study. The presence and severity of DR were determined by grading fundus photographs according to the Early Treatment Diabetic Retinopathy Study(ETDRS) retinopathy scale. Systolic and diastolic blood pressure(SBP and DBP) were recorded using an electronic sphygmomanometer. Intraocular pressure(IOP) was measured using an iCare rebound tonometer. MOPP was calculated using the formula MOPP = 2/3 [DBP + 1/3(SBP-DBP)]-*** In total, 1,857 patients who had gradable fundus photography and MOPP data were enrolled in this study. Male patients had a higher MOPP than female patients(52.25 ± 8.75 vs. 50.96 ± 8.74 mmHg, P = 0.002). Overall, both male and female patients with any type of DR, non-proliferative DR(NPDR), or non-sight-threatening DR(non-STDR) had significantly higher MOPP relative to patients without DR. Increased MOPP(per 1 mmHg) was in turn associated with the presence of any type of DR[odds ratio(OR) = 1.03, 95% confidence interval(CI) : 1.02–1.04], NPDR(OR = 1.03 95% CI: 1.02–1.04),and non-STDR(OR = 1.03, 95% CI: 1.01–1.04) after adjusting for confounders. Increased MOPP(per 1 mmHg) was also associated with an increased likelihood of macular edema(OR = 1.02, 95% CI:1.01–1.04).Conclusions The results suggest that increased MOPP was associated with DR and macular edema in northeastern Chinese patients with T2 DM.

关键词： Diabetic retinopathy Ocular perfusion pressure Systolic blood pressure Diastolic blood pressure

Graphene-based materials for polymer solar cells

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Chinese Chemical Letters 2016年第8期27卷 1259-1270,1468页

作者： Xiao-feng lin Zi-Yan Zhang zhong-Ke yuan Jing li Xiao-Fen Xiao Wei Hong Xu-Dong Chen ding-Shan Yu Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education of China School of Chemistry and Chemical EngineeringSun Yat-sen University Key Laboratory of High Performance Polymer-based Composites of Guangdong Province School of Chemistry and Chemical Engineering Sun Yat-sen University

Due to the remarkable electronic,optical,thermal,and mechanical properties,graphene-based materials have shown great potential in a wide range of technique ***,the high transparency,conductivity,flexibility,and abundance make graphene materials highly attractive for polymer solar cells（PSCs）.Graphene-based materials have been regarded as one promising candidate used in various parts in PSCs not only as electrodes,but also as interfacial layers and active layers with an aim to boost the power conversion efficiency of the *** this review,we summarize the recent progress about the design and synthesis of graphene-based materials for efficient PSCs along with the related challenges and future perspectives.

关键词： Graphene Polymer solar cells Electrodes Interfacial layers Active layers

Influence of Sea Surface Temperature on the Predictability of Idealized Tropical Cyclone Intensity

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Journal of Tropical Meteorology 2021年第4期27卷 355-367页

作者： zhong Quan-jia li Jian-ping li Shu-wen WANG yuan ding Rui-qiang ZHANG li-feng State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029 China Multispheres and Earth System(FDOMES)/Key Laboratory of Physical Oceanography/Academy of the Future Oceans Ocean University of ChinaQingdaoShandong 266100 China Laboratory for Ocean Dynamics and Climate Pilot Qingdao National Laboratory for Marine Science and TechnologyQingdaoShandong 266100 China Key Laboratory of Cloud-Precipitation Physics and Severe Storms(LACS) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029 China College of Meteorology and Oceanography National University of Defense TechnologyNanjing 211101 China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875 China

The role of sea surface temperature(SST)forcing in the development and predictability of tropical cyclone(TC)intensity is examined using a large set of idealized numerical experiments in the Weather Research and Forecasting(WRF)*** results indicate that the onset time of rapid intensification of TC gradually decreases,and the peak intensity of TC gradually increases,with the increased magnitude of *** predictability limits of the maximum 10 m wind speed(MWS)and minimum sea level pressure(MSLP)are~72 and~84 hours,*** of the analyses of variance for different simulation time confirm that the MWS and MSLP have strong signal-to-noise ratios(SNR)from 0-72 hours and a marked decrease beyond 72 *** the horizontal and vertical structures of wind speed,noticeable decreases in the magnitude of SNR can be seen as the simulation time increases,similar to that of the SLP or perturbation *** results indicate that the SST as an external forcing signal plays an important role in TC intensity for up to 72 hours,and it is significantly weakened if the simulation time exceeds the predictability limits of TC intensity.

关键词： predictability nonlinear local Lyapunov exponent signal-to-noise ratios tropical cyclone intensity sea surface temperature

Prevalence of and risk factors for diabetic macular edema in a northeastern Chinese population

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International Journal of Ophthalmology(English edition) 2022年第2期15卷 320-326页

作者： zhong lin feng-Hua Wang liang Wen Yu Wang Dong li Xiao-Xia ding Yu Dou Gang Zhai yuan-Bo liang The Eye Hospital School of Ophthalmology and OptometryWenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina National Clinical Research Center for Ocular Diseases Wenzhou 325027Zhejiang ProvinceChina Beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical UniversityBeijing Ophthalmology&Visual Science Key LabBeijing 100730China Fushun Eye Hospital Fushun 113006Liaoning ProvinceChina

AIM:To estimate the prevalence of diabetic macular edema(DME) and clinically significant macular edema(CSME),and to assess their risk factors in a population with type 2 diabetic mellitus(T2DM) located in northeast ***:Patients were included from the Fushun Diabetic Retinopathy Cohort Study(FS-DIRECT),a community-based study conducted in northeast *** presence of DME and CSME was determined by the Early Treatment Diabetic Retinopathy Study(ETDRS) retinopathy scale of fundus *** age-standardized prevalence of DME and CSME was *** association between DME/CSME and risk factors was analyzed in a multivariate Logistical ***:A total of 292(15.4%) and 166(8.8%) patients were diagnosed as DME and CSME,yielding the age and sex standardized prevalence of 13.5%(95%CI:11.9%-15.0%),and 7.1%(95%CI:5.9%-8.3%),*** patients had a higher prevalence of DME compared to their male counterparts(15.7% vs 10.4%,P=0.03).Multivariable Logistic regression analysis showed that younger age,insulin use,proteinuria,longer duration of diabetes,and higher glycosylated hemoglobin A1c,were associated with the prevalence of DME and *** with higher fasting plasma glucose,systolic blood pressure,and blood urea nitrogen were also found to be associated with ***:Early fundus screening in diabetic patients is invaluable and given the relatively high prevalence of DME and CSME in this study cohort,those with a high risk of sight threatening maculopathy would invariably benefit from earlier detection.

关键词： diabetic macular edema clinically significant macular edema diabetic retinopathy

基于BP神经网络的外姿态测量系统线阵CCD标定

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仪器仪表学报 2010年第5期31卷 1138-1141页

作者：李晶袁峰丁振良哈尔滨工业大学电气工程及自动化学院哈尔滨150001

在基于线阵CCD相机的空间物体外姿态测量系统中,线阵CCD相机的标定是空间合作目标定位的一个重要步骤。利用神经网络所具有的处理复杂非线性映射问题的能力,提出了基于反向传播(BP)神经网络的线阵CCD标定方法。该方法能够很好地描述外... 详细信息

在基于线阵CCD相机的空间物体外姿态测量系统中,线阵CCD相机的标定是空间合作目标定位的一个重要步骤。利用神经网络所具有的处理复杂非线性映射问题的能力,提出了基于反向传播(BP)神经网络的线阵CCD标定方法。该方法能够很好地描述外姿态测量系统中三维空间合作目标与像点之间的映射关系,无需建立复杂的数学模型,可直接恢复空间合作目标的三维信息,从而计算空间物体的姿态信息。实验结果表明:基于BP神经网络的线阵CCD标定方法与传统的DLT方法比较精度可提高41.7%。

关键词：外姿态测量线阵CCD标定反向传播(BP)神经网络

Chiral quantum heating and cooling with an optically controlled ion

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light(Science & Applications) 2024年第7期13卷 1393-1400页

作者： Jin-Tao Bu Jian-Qi Zhang Ge-Yi ding Jia-Chong li Jia-Wei Zhang Bin Wang Wen-Qiang ding Wen-Fei yuan liang Chen Qi zhong Ali Keçebaş Şahin KÖzdemir Fei Zhou Hui Jing Mang feng State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsInnovation Academy of Precision Measurement Science and TechnologyChinese Academy of Sciences430071 WuhanChina. University of the Chinese Academy of Sciences 100049 BeijingChina. Research Center for Quantum Precision Measurement Guangzhou Institute of Industry Technology511458 GuangzhouChina. Department of Engineering Science and Mechanics and Materials Research InstitutePennsylvania State UniversityUniversity ParkState CollegePA 16802USA. Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal University410081 ChangshaChina. Department of Physics Zhejiang Normal University321004 JinhuaChina

Quantum heat engines and refrigerators are open quantum systems,whose dynamics can be well understood using a non-Hermitian formalism.A prominent feature of non-Hermiticity is the existence of exceptional points(EPs),which has no counterpart in closed quantum *** has been shown in classical systems that dynamical encirclement in the vicinity of an EP,whether the loop includes the EP or not,could lead to chiral mode ***,we show that this is valid also for quantum systems when dynamical encircling is performed in the vicinity of their liouvillian EPs(LEPs),which include the effects of quantum jumps and associated noise—an important quantum feature not present in previous *** demonstrate,using a Paul-trapped ultracold ion,the first chiral quantum heating and refrigeration by dynamically encircling a closed loop in the vicinity of an *** witness the cycling direction to be associated with the chirality and heat release(absorption)of the quantum heat engine(quantum refrigerator).Our experiments have revealed that not only the adiabaticity breakdown but also the Landau–Zener–Stückelberg process play an essential role during dynamic encircling,resulting in chiral thermodynamic *** observations contribute to further understanding of chiral and topological features in non-Hermitian systems and pave a way to exploring the relation between chirality and quantum thermodynamics.

关键词： quantum chiral dynamical

Ethylene promotes seed iron storage during Arabidopsis seed maturation via ERF95 transcription factor

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Journal of Integrative Plant Biology 2020年第8期62卷 1193-1212页

作者： Ying Sun Jia Qi li Jing Ying Yan Jun Jie yuan Gui Xin li Yun Rong Wu Ji Ming Xu Rong feng Huang Nicholas P.Harberd zhong Jie ding Shao Jian Zheng State Key Laboratory of Plant Physiology and Biochemistry College of Life SciencesZhejiang UniversityHangzhou 310058China Agricultural Experimental Station Zhejiang UniversityHangzhou 310058China College of Agronomy and Biotechnology Zhejiang UniversityHangzhou 310058China Biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijing 100081China Department of Plant Science University of OxfordOxford OX13RBUnited Kingdom

Because Iron(Fe)is an essential element,Fe storage in plant seeds is necessary for seedling establishment following ***,the mechanisms controlling seed Fe storage during seed development remain largely *** we reveal that an ERF95 transcription factor regulates Arabidopsis seed Fe *** show that expression of ERF95 increases during seed maturation,and that lack of ERF95 reduces seed Fe accumulation,consequently increasing sensitivity to Fe deficiency during seedling ***,overexpression of ERF95 has the opposite *** show that lack of ERF95 decreases abundance of FER1 messenger RNA in developing seed,which encodes Fe-sequestering ***,a fer1-1 loss-of-function mutation confers reduced seed Fe accumulation,and suppresses ERF95-promoted seed Fe *** addition,ERF95 binds to specific FER1 promoter GCC-boxes and transactivates FER1 *** show that ERF95 expression in maturing seed is dependent on EIN3,the master transcriptional regulator of ethylene *** lack of EIN3 reduces seed Fe content,overexpression of ERF95 rescues Fe accumulation in the seed of ein3 loss-of-function ***,we show that ethylene production increases during seed *** conclude that ethylene promotes seed Fe accumulation during seed maturation via an EIN3-ERF95-FER1-dependent signaling pathway.

关键词： expression. ERF Arabidopsis

Decreasing self-heat effect in platinum resistance temperature measurement

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Decreasing self-heat effect in platinum resistance temperatu...