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Complex geometry and real geometry

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Science China Mathematics 2005年第Z1期48卷 206-216页

作者： YU yanlin ZHU Lin feng Xiuhong Department of Mathematics Suzhou UniversitySuzhou215006China Department of MathematicsSuzhou UniversitySuzhou215006China Department of MathematicsSuzhou UniversitySuzhou215006China

There is a well-known way to generalize the Riemann-Roch operator for Kahler manifold to that for Hermitian manifold. In this paper we show a slightly different way to get a generalized Riemann-Roch operator, which is just the Dirac operator. The difference between the two operators is that the latter one enables the so-called Pythagoras equalities.

关键词： spinor, bispinor, Clifford algebra, Jack map, Pythagoras relation

飞行时间和点扩散函数对18F-FDGPET/CT肺癌纵隔淋巴结转移的增益价值

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中国医学影像学杂志 2024年第7期32卷 686-691页

作者：黄克敏冯彦林刘德军梁伟棠李林冯叶霞邓大浪贺伟平广东省佛山市第一人民医院核医学科广东佛山528000

目的探讨飞行时间(TOF)和点扩散函数(PSF)重建对18F-FDGPET/CT显像肺癌纵隔淋巴结转移的增益价值。资料与方法回顾性分析2020年3月9日—2021年7月23日在佛山市第一人民医院行PET/CT检查的肺癌纵隔淋巴结转移患者68例。分别采用有序子集... 详细信息

目的探讨飞行时间(TOF)和点扩散函数(PSF)重建对18F-FDGPET/CT显像肺癌纵隔淋巴结转移的增益价值。资料与方法回顾性分析2020年3月9日—2021年7月23日在佛山市第一人民医院行PET/CT检查的肺癌纵隔淋巴结转移患者68例。分别采用有序子集最大期望值迭代法(OSEM)、OSEM+TOF、OSEM+PSF、OSEM+TOF+PSF重建图像,比较不同重建算法对肺癌纵隔淋巴结转移病灶的分辨能力,以及病灶信噪比(SNR)和标准化摄取值(SUV)的差异。结果使用OSEM+TOF+PSF重建可获得病灶SUVmax、SUVmean和SNR的最高值,与常规OSEM比较分别增加了21.99%、22.86%和60.14%(t=28.321、19.11、11.059,P均22 mm的较大病灶(24.1%比21.1%、25.3%比19.3%、70.6%比63.3%;Z=-3.658、-4.313、-2.154,P均15.31的高对比度病灶(23.6%比21.4%、25.3%比21.1%、85.7%比46.0%;Z=-3.519、-2.336、-5.106,P均<0.05);在不同重建算法的病灶可检测性评价结果中,OSEM+TOF+PSF图像对纵隔淋巴结转移病灶的显示最清晰,其中87.4%的病灶为明确存在,显著高于OSEM图像的73.1%(χ^(2)=11.704,P=0.001),但OSEM+PSF图像中病灶明确存在的比例与OSEM比较并未显著增加(73.1%比75.8%;χ^(2)=0.361,P=0.548)。结论TOF和PSF结合能显著提高肺癌纵隔淋巴结转移病灶的探测能力,以及病灶SNR和SUV,尤其在小病灶和低对比度病灶中更为显著。

关键词：肺肿瘤体层摄影术,发射型计算机飞行时间点扩散函数淋巴结

Crystallographic facet-dependent stress responses by polyhedral lead sulfide nanocrystals and the potential ＂safe-by-design＂ approach

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Nano Research 2016年第12期9卷 3812-3827页

作者： Yun Chang Kai Li yanlin feng Ning Liu Yan Cheng Xiujuan Sun Yuqing feng Xi Li Zhijian Wu Haiyuan Zhang Laboratory of Chemical Biology Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China School of Chemistry and Life Science Changchun University of Technology Changchun 130012 China

The particular physicochemical properties of nanomaterials are able to elicit unique biological responses. The property activity relationship is usually established for in-depth understanding of toxicity mechanisms and designing safer nanomaterials. In this study, the toxic role of specific crystallographic facets of a series of polyhedral lead sulfide （PbS） nanocrystals, including truncated octahedrons, cuboctahedrons, truncated cubes, and cubes, was investigated in human bronchial epithelial cells （BEAS-2B） and murine alveolar macrophages （RAW 264.7） cells./100} facets were found capable of triggering facet-dependent cellular oxidative stress and heavy metal stress responses, such as glutathione depletion, lipid peroxidation, reactive oxygen species （ROS） production, heme oxygenase-1 （HO-1） and metallothionein （MT） expression, and mitochondrial dysfunction, while {111} facets remained inert under biological conditions. The {100}-facet-dependent toxicity was ascribed to {100}-facet-dependent lead dissolution, while the low lead dissolution of {111} facets was due to the strong protection afforded by poly（vinyl pyrrolidone） during synthesis. Based on this facet-toxicity relationship, a ＂safe-by-design＂ strategy was designed to prevent lead dissolution from {100} facets through the formation of atomically thin lead-chloride adlayers, resulting in safer polyhedral PbS nanocrystals.

关键词： nanomaterials facet metal dissolution safe-by-design toxicity

Energy and exergy analyses and optimizations for two-stage TEC driven by two-stage TEG with Thomson effect

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Science China(Technological Sciences) 2024年第4期67卷 1077-1093页

作者： CHEN LinGen GE yanlin feng HuiJun REN TingTing Institute of Thermal Science and Power Engineering Wuhan Institute of TechnologyWuhan 430205China Hubei Provincial Engineering Technology Research Center of Green Chemical Equipment Wuhan 430205China School of Mechanical&Electrical Engineering Wuhan Institute of TechnologyWuhan 430205China

Based on the non-equilibrium thermodynamics and energy and exergy analyses,a thermodynamic model of two-stage thermoelectric(TE)cooler(TTEC)driven by two-stage TE generator(TTEG)(TTEG-TTEC)combined TE device is established with involving Thomson effect by fitting method of variable physical parameters of TE *** total number of TE elements as constraint,influences of number distributions of TE elements on three device performance indictors,that is,cooling load,maximum COP and maximum exergetic efficiency,are *** number distributions of TE elements are optimized with three maximum performance indictors as the objectives,*** of hot-junction temperature of TTEG and coldjunction temperature of TTEC on optimization results are analyzed,and difference between optimization results corresponding to three performance indicators are *** performance intervals and optimal variable intervals are *** of Thomson effect on three general performance indicators,three optimal performance indicators and optimal variables are comparatively *** effect reduces three general performance indicators and three optimal performance indicators of *** hot-and cold-junction temperatures of TTEG and TTEC are 450,305,325 and 295 K,respectively,Thomson effect reduced maximum cooling load,maximum COP and maximum exergetic efficiency from 9.528 W,9.043×10^(-2)and2.552%to 6.651 W,6.286×10^(-2)and 1.752%,respectively.

关键词： non-equilibrium thermodynamics cooling load COP exergetic efficiency combined thermoelectric device performance optimization

Constructal design of a rectangular porous fin considering minimization of maximum temperature difference and pumping power consumption

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Science China(Technological Sciences) 2024年第3期67卷 919-929页

作者： LIU XiaoYe feng HuiJun CHEN LinGen GE yanlin Institute of Thermal Science and Power Engineering Wuhan Institute of TechnologyWuhan 430205China College of Power Engineering Naval University of EngineeringWuhan 430033China Hubei Provincial Engineering Technology Research Center of Green Chemical Equipment Wuhan 430205China School of Mechanical&Electrical Engineering Wuhan Institute of TechnologyWuhan 430205China

A heat dissipation model of a rectangular porous fin is established based on constructal theory. First, the constructal design of rectangular porous fin is conducted by selecting a complex function minimization, which composed of linear weighting sum of maximum temperature difference and pumping power consumption, as optimization objective. Effects of gap height, air inlet velocity, total porous fin volume and porosity on the optimal constructs are investigated, respectively. The findings show that the complex function can attain its double minimum at a value of 0.802 when the fin length and number are optimized, and the corresponding optimal fin length and number are 8.01 mm and 10, respectively. In comparison to original design, the complex function and maximum temperature difference after twice optimization are decreased by 19.80% and 66.31%, ***, the comprehensive performance of porous fin is improved by simultaneously optimizing the fin length and number. The artificial neural network is applied to predict the fin performances, which is used to conduct multi-objective optimization based on NSGA-II algorithm. Optimal structure of porous fin for multiple requirements is gained by LINMAP and TOPSIS decisionmaking strategies. The findings in this study can serve as theoretical guides for fin thermal designs of electronic devices.

关键词： constructal theory rectangular porous fin pumping power consumption maximum temperature difference complex function multi-objective optimization

Constructal design of a rectangular parallel phase change microchannel in a three-dimensional electronic device

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Science China(Technological Sciences) 2024年第5期67卷 1381-1390页

作者： ZHANG JiWen feng HuiJun CHEN LinGen GE yanlin Institute of Thermal Science and Power Engineering Wuhan Institute of TechnologyWuhan430205China College of Power Engineering Naval University of EngineeringWuhan430033China Hubei Provincial Engineering Technology Research Center of Green Chemical Equipment Wuhan430205China School of Mechanical&Electrical Engineering Wuhan Institute of TechnologyWuhan430205China

Based on constructal theory,a rectangular parallel phase change microchannel model in a three-dimensional electronic device(TDED)is established with R134a as the cooling *** on the minimization of a complex function(CF)composed of linear weighting sum of maximum temperature difference and pumping power consumption,constructal design of the TDED is conducted first;and then,maximum temperature difference and pumping power consumption are minimized by non-dominated sorting genetic algorithm-II *** results reveal that there exist an optimal mass flow rate(0.0012 kg/s)and a quadratic optimal aspect ratio(AR)(0.39)of the microchannel which lead to quadratic minimum CF(0.817).Compared with the original value,the CF after optimization is reduced by 18.34%.Reducing the inlet temperature of cooling fluid and microchannel number appropriately can help to enhance the overall performance of *** using the artificial neural network and genetic algorithms in the toolboxes of Matlab software,the optimal AR gained in the Pareto solution set is located between 0.2–*** smallest deviation index among three discussed strategies is 0.346,and the corresponding optimal AR is 0.413,which is selected as the optimal design strategy of the microchannel in the TDED under multiple *** findings in this study can serve as theoretical guides for thermal designs of electronic devices.

关键词： constructal theory parallel microchannel evaporation phase change three-dimensional electronic device multi-objective optimization artificial neural network

兴奋性氨基酸转运体家族及其在眼科疾病中的研究进展

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眼科学报 2024年第6期39卷 291-298页

作者：胡晨阳(综述) 冯砚琳许跃黄晶晶(审校) 中山大学中山眼科中心眼病防治全国重点实验室广东省眼科视觉科学重点实验室广州510060

谷氨酸是哺乳动物中枢神经系统中的主要兴奋性神经递质,谷氨酸酶系统的持续激活会导致神经元的兴奋性毒性,进而引起神经元损伤和细胞死亡。兴奋性氨基酸转运体家族成员是一种多次跨膜蛋白,位于突触前膜、突触囊泡和神经胶质细胞膜上,也... 详细信息

谷氨酸是哺乳动物中枢神经系统中的主要兴奋性神经递质,谷氨酸酶系统的持续激活会导致神经元的兴奋性毒性,进而引起神经元损伤和细胞死亡。兴奋性氨基酸转运体家族成员是一种多次跨膜蛋白,位于突触前膜、突触囊泡和神经胶质细胞膜上,也是一种高亲和力的钠钾依赖性载体,能够不断清除细胞外残留的谷氨酸,维持正常的突触内外谷氨酸水平和细胞内氧化还原稳态,对于保护细胞免受兴奋性毒性以及氧化应激损伤至关重要,兴奋性氨基酸转运体家族成员表水平达的失调与多种中枢神经系统疾病神经退行性变的发生和发展密切相关。在视网膜组织中,兴奋性氨基酸转运体家族成员广泛表达。目前大量研究表明,兴奋性氨基酸转运体家族成员广泛参与了青光眼、视网膜缺血再灌注损伤、年龄相关性黄斑变性等眼部疾病的发病,但具体机制有待进一步阐明。为此,文章综述了兴奋性氨基酸转运体家族成员的生理功能及其在相关眼科疾病发生和发展中作用的研究进展,为进一步阐明相关眼病发病的分子机制及新的防治靶点的发现提供新的视角。

关键词：兴奋性氨基酸转运体谷氨酸眼科疾病

Constructal design of printed circuit recuperator for S-CO_(2)cycle via multi-objective optimization algorithm

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Science China(Technological Sciences) 2024年第1期67卷 285-294页

作者： DAN ZhiSong feng HuiJun CHEN LinGen LIAO NaiBing GE yanlin Institute of Thermal Science and Power Engineering Wuhan Institute of TechnologyWuhan 430205China College of Power Engineering Naval University of EngineeringWuhan 430033China Hubei Provincial Engineering Technology Research Center of Green Chemical Equipment Wuhan 430205China School of Mechanical&Electrical Engineering Wuhan Institute of TechnologyWuhan 430205China AECC Hunan Aviation Powerplant Research Institute Zhuzhou 412002China

Based on a constructal theory,the structure design of a printed circuit recuperator with a semicircular heat transfer channel for supercritical CO_(2)cycle is carried ***,a complex function composed of weighted sum of the reciprocal of total heat transfer rate and total pumping power consumption is regarded as an optimization objective,and total volumes of the recuperator and heat transfer channel are regarded as *** optimal heat transfer channel radius and minimum complex function of the recuperator are *** turns out that heat transfer rate,pumping power consumption,and complex function under the optimal construct of recuperator are reduced by 15.10%,82.44%,and 32.33%,*** exists the optimal single plate channel number which results in the double minimum complex ***,for the purpose of minimizing the reciprocal of heat transfer rate and pumping power consumption,NSGA-II algorithm is used to achieve multi-objective optimization,and the minimum deviation index derived by the decision-making methods is 0.076,which can be taken as multi-objective optimal design scheme for printed circuit recuperator with semicircular heat transfer *** findings presented here can serve as theoretical recommendations for the structure design of printed circuit recuperator.

关键词： constructal theory supercritical CO_(2)cycle printed circuit heat exchanger heat transfer rate pumping power consumption multi-objective optimization

Polydopamine and ammonium bicarbonate coated and doxorubicin loaded hollow cerium oxide nanoparticles for synergistic tumor therapy

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Nano Research 2019年第12期12卷 2947-2953页

作者： Keqiang Xu Yan Cheng Jiao Yan yanlin feng Runxiao Zheng Xiaqhig Wu Yanjing Wang Panpan Song Haiyuan Zhang Laboratory of Chemical Biology Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology cf China Hefei 230026China

The development of effective nanoplatforms is extremely necessary for cancer ***,we prepared polydopamine(PDA)andammonium bicarbonate(NH4HCO3)coated and doxorubicin(Dox)loaded hollow cerium oxide(CeO2)NPs(PDAC NPs),which showedexcellent synergistic effect for photothermal therapy,chemotherapy and chemodynamic *** near infrared laser irradiation,PDA shell could absorb the incident light and convert it into heat,which could not only kill tumor cells with hyperthermia,but also trigger thedecomposition of NH4HCO3 into gaseous carbon dioxide and ammonia,leading to the destroy of PDA *** leakage of PDA furtheraccelerated Dox release and exposed CeO2 surface,in which Dox could enter into cell nucleus to induce chemotherapy,and CeO2 couldcatalyze cellular hydrogen peroxide into hydroxyl radical to present chemodynamic *** fact,PDAC NPs showed an excellenttherapeutic efficacy both in vitro and in *** design provides a new strategy for synergistic tumor therapy.

关键词： photothermal therapy chemotherapy chemodynamic therapy polydopamine cerium oxide