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Synthesis of 6-(Bromomethyl)-4-methoxy-5,6,7,8-tetrahydropyrido-[3,2.d]pyrimidin-2.ol from 6-Methylpyrimidine-2.4-diol

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Chemical Research in chinese Universities 2012年第1期28卷 57-60页

作者： LIU Wei-dong2. DENG Xi-ling2. {1. Zhi-li2. {2. Xiao-wei2.and LIU Jun-yi1.2.1. State Key Laboratory of Natural and Biomimetic Drug, 2. Department of Chemical Biology, School of Pharmaceutical Sciences, Peking University, Beijing 1.01.1. P. R. china Peking Univ Sch Pharmaceut Sci State Key Lab Nat & Biomimet Drug Beijing 100191 Peoples R China Peking Univ Sch Pharmaceut Sci Dept Biol Chem Beijing 100191 Peoples R China

6-（Bromomethyl）-4-methoxy-5,6,7,8-tetrahydropyrido[3,2.d]pyrimidin-2.ol（compound 9） was synthe sized from 6-methylpyrimidine-2.4-diol（compound 1. through the crucial steps of 6-methyl alkylating and intramo lecular cyclization. The assignment of the structure of compound 9 was performed by its spectral data, 1. NMR, 1.C NMR, HMBC, and HRMS spectra.

关键词： Heterocycle Carbanion Alkylation Reduction Cyclization

IPSO-BPNN:一种结合粒子群优化的BP神经网络透射光谱水质亚硝酸盐含量定量化模型

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光谱学与光谱分析 2024年第11期44卷 3172-3178页

作者：王彩玲张国浩西安石油大学计算机学院

亚硝酸盐是一种常见的水质污染物，主要来源为废水、肥料和污水处理厂等。水质中亚硝酸盐浓度大小是评估水体健康程度的一个重要指标，但传统的亚硝酸盐浓度检测方法操作复杂且容易受到检测环境的干扰，无法直观和准确的反映出水质健康... 详细信息

亚硝酸盐是一种常见的水质污染物，主要来源为废水、肥料和污水处理厂等。水质中亚硝酸盐浓度大小是评估水体健康程度的一个重要指标，但传统的亚硝酸盐浓度检测方法操作复杂且容易受到检测环境的干扰，无法直观和准确的反映出水质健康程度。为了探究一种新的方式来评估水体的健康程度，使用IPSO-BPNN模型对亚硝酸盐透射光谱数据进行浓度预测。首先选择1.种浓度的亚硝酸盐标准溶液(0.02. 0.04、 0.06、 0.08、 0.1.、 0.1.、 0.1.、 0.1.、 0.1.和0.2. mg·L-1.使用OCEAN-HDX-XR微型光谱仪在相同的时间间隔下对十个浓度的亚硝酸盐溶液进行扫描，并通过白板校正得到光谱数据的光谱透射率值。使用最大最小归一化、均值中心化两种预处理方法将光谱数据进行维度和中心点的统一，使得不同样本之间的光谱数据具有可比性和可解释性。由于原始光谱数据维度较高，采用核主成分分析进行数据降维，选择代表原始数据97.94%信息的6个主成分进行IPSO-BPNN模型的训练。在预测亚硝酸盐浓度时，对原始粒子群优化算法进行了改进，引入了自适应学习因子和惯性权重更新公式以及粒子种群多样性引导策略，并在BP神经网络的基础上引入了学习率自适应公式，提高了算法的性能。通过比较不同粒子数进行迭代的函数适应度值变化曲线，选择使用1.0个粒子进行30次迭代来寻找最优权重和偏置组合。结果显示，IPSO-BPNN预测模型的决定系数为0.984 360,均方根误差为0.006 92.,平均绝对误差为0.004 1.3,与当前预测性能较好的随机森林模型、线性回归模型、 BP-ANN模型、 PSO-BPNN模型和PSO-SVR模型相比，该模型的拟合效果更好，精确度更高。基于以上结果，提出了一种基于IPSO-BPNN模型的高光谱水质亚硝酸盐浓度预测方法，为水体健康程度的评估提供了新的思路。

关键词：高光谱亚硝酸盐 IPSO-BPNN模型 KPCA 水质检测

PRSS50-mediated inhibition of MKP3/ERK signaling is crucial for meiotic progression and sperm quality

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Zoological Research 2024年第5期45卷 1037-1047页

作者： Chun-Xue Niu Jia-Wei Li Xiao-Li Li Lin-Lin zhang Yan Lang Zhen-Bo Song Chun-Lei Yu Xiao-Guang Yang Hai-Feng Zhao Jia-{1. Sun Li-Hua Zheng Xue {2. Ying Sun Xiao-Hong Han Guan-Nan {2. Yong-Li Bao National Engineering Laboratory for Druggable Gene and Protein Screening Northeast Normal UniversityChangchunJilin 130117China china International Joint Research Center for Human Stem Cell Bank Northeast Normal UniversityChangchunJilin 130117China Jilin institute for Drug Control ChangchunJilin 130022China

Serine protease 50(PRSS50/TSP50)is highly expressed in *** study investigated its role in testicular development and ***,PRSS50 knockdown was observed to impair DNA synthesis in *** further explore this,we generated PRSS50 knockout(Prss50^(−/−))mice(Mus musculus),which exhibited abnormal spermatid nuclear compression and reduced male ***,dysplastic seminiferous tubules and decreased sex hormones were observed in 4-week-old Prss50^(−/−)mice,accompanied by meiotic progression defects and increased apoptosis of spermatogenic *** analysis indicated that PRSS50 deletion resulted in increased phosphorylation of extracellular signal-regulated protein kinases 1.and 2.ERK1.2.and elevated levels of MAP kinase phosphatase 3(MKP3),a specific ERK antagonist,potentially accounting for testicular dysplasia in adolescent Prss50−/−*** together,these findings suggest that PRSS50 plays an important role in testicular development and spermatogenesis,with the MKP3/ERK signa{2. pathway playing a significant role in this process.

关键词： PRSS50(TSP50) Meiotic progression Sperm quality MKP3 ERK

PCDH1. restricts dendritic spine morphogenesis by regulating ROCK2.dependent control of the actin cytoskeleton,modulating emotional behavior

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Zoological Research 2024年第3期45卷 535-550页

作者： Laidong Yu Fangfang Zeng Mengshu Fan Kexuan zhang Jingjing Duan Yalu Tan Panlin Liao Jin Wen Chenyu {1. Meilin {1. Jialong Yuan Xinxin Pang Yan Huang Yangzhou zhang Jia-Da Li Zhuohua zhang Zhonghua Hu Hunan Key Laboratory of Molecular Precision Medicine Department of Critical Care MedicineXiangya HospitalCentral South UniversityChangshaHunan 410008China Center for Medical Genetics and Hunan Key Laboratory of Medical Genetics School of Life SciencesCentral South UniversityChangshaHunan 410008China National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangshaHunan 410008China Hunan Provincial Clinical Research Center for Critical Care Medicine Xiangya HospitalCentral South UniversityChangshaHunan 410008China Hunan Key Laboratory of Animal Models for Human Diseases School of Life SciencesCentral South UniversityChangshaHunan 410008China MOE Key Lab of Rare Pediatric Diseases School of Life SciencesCentral South UniversityChangshaHunan 410008China Department of Neurosciences University of South China Medical SchoolHengyangHunan 421001China

Proper regulation of synapse formation and elimination is critical for establishing mature neuronal circuits and maintaining brain *** abnormalities,such as defects in the density and morphology of postsynaptic dendritic spines,underlie the pathology of various neuropsychiatric *** 1.(PCDH1.)is associated with major mood disorders,including bipolar disorder and ***,the molecular mechanisms by which PCDH1. regulates spine number,morphology,and behavior remain *** this study,we found that PCDH1. functions at postsynaptic sites,restricting the number and size of dendritic spines in excitatory *** overexpression of PCDH1. in the ventral hippocampal CA1.results in spine loss and anxiety-and depression-like behaviors in ***,PCDH1. interacts with actin-relevant proteins and regulates actin filament(F-actin)***,PCDH1. binds to ROCK2.increasing its expression and subsequently enhancing the activity of downstream targets such as LIMK1.and the phosphorylation of cofilin serine-3(Ser3).Inhibition of ROCK2.activity with belumosudil(KD02.)ameliorates the defective F-actin organization and spine structure induced by PCDH1. overexpression,suggesting that ROCK2.mediates the effects of PCDH1. on F-actin content and spine ***,these findings reveal a novel mechanism by which PCDH1. regulates synapse development and behavior,providing pathological insights into the neurobiological basis of mood disorders.

关键词： Synapse development Dendritic spine Mood disorder Actin cytoskeleton Animal behavior

Research on trusted computing and its development

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Science china(Information Sciences) 2010年第3期53卷 405-433页

作者： SHEN ChangXiang1. zhang HuanGuo1., {1. HuaiMin3, {1. Ji3, ZHAO Bo2. YAN Fei2. YU FaJiang2. zhang LiQiang2.& XU MingDi2.0}eijing University of Technology, Beijing 1.01.4, china 2.chool of Computer, Wuhan University, Key Laboratory of Aerospace Information Security and Trusted Computing of Ministry of Education, Wuhan 430072. china 3School of Computer, National University of Defence Technology, changsha 430074, china 1. Beijing University of Technology Beijing 100124 China3. School of Computer National University of Defence Technology Changsha 430074 China2. Key Laboratory of Aerospace Information Security and Trusted Computing of Ministry of Education School of Computer Wuhan University Wuhan 430072 China

Trusted computing is a novel technology of information system security. It has become a new tide in worldwide information security area and achieved inspiring accomplishment. In china, the initiative research of trusted computing is not late, and the achievements are plentiful and substantial. Our country is in the front rank of the world in trusted computing. This paper comprehensively illustrates the recent development in theory and technology of trusted computing, introduces some improvements in trusted computing in our country, and proposes our opinions and viewpoints towards the existing problems in trusted computing and its future development.

关键词： information security trusted computing trusted computing platform trustworthy software trusted network connection

General Admissibility for Linear Estimators of Multivariate Random Regression Coefficients and Parameters with Respect to a Restricted Parameter Set

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Journal of Shanghai Jiaotong university(Science) 2009年第6期14卷 742-746页

作者：肖爱玲王志忠 School of Info-physics and Geometics Engineering Central South University School of Informeties Guangdong University of Foreign Studies School of Mathematica Science and Computing Technology Central South University

This paper considers the linear model effected by random disturbance,Y=XB+ε,where [~B_ε]～([^(AΘ)_0],VΣ),and ΘTATX TN XAΘΣ.It gives a definition for general admissible estimator of a linear function SΘ + GB of random regression coefficients and *** necessary and sufficient conditions for LY and LY + C to be general admissible estimators of SΘ + GB in the class of both homogenous and non-homogenous linear estimators are *** conclusion is not dependent of whether or not SΘ + GB is estimable.

关键词： parametric matrix linear estimator general optimality general admissibility

Diffusion and reaction mechanism of limestone and quartz in fluxed iron ore pellet roasting process

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 485-497页

作者： Yufeng Guo Jinlai zhang Shuai {1. Jianjun Fan Haokun Li Feng Chen Kuo Liu {2.zhi Yang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Technology Center Taiyuan Iron Steel(Group)Co.Ltd.(TISCO)Taiyuan 030003China

The increase to the proportion of fluxed pellets in the blast furnace burden is a useful way to reduce the carbon emissions in the ironmaking *** this study,the interaction between calcium carbonate and iron ore powder and the mineralization mechanism of fluxed iron ore pellet in the roasting process were investigated through diffusion couple *** electron microscopy with energy dispersive spectroscopy was used to study the elements’diffusion and phase transformation during the roasting *** results indicated that limestone decomposed into calcium oxide,and magnetite was oxidized to hematite at the early stage of *** the increase in roasting temperature,the diffusion rate of Fe and Ca was obviously accelerated,while the diffusion rate of Si was relatively *** order of magnitude of interdiffusion coefficient of Fe_(2.O_(3)-CaO diffusion couple was 1.^(−1.) m^(2.·s^(−1. at a roasting temperature of 1.00℃for 9 ***_(2.Fe_(2.O_(5) was the initial product in the Fe_(2.O_(3)-CaO-SiO_(2. diffusion interface,and then Ca_(2.Fe_(2.O_(5) continued to react with Fe_(2.O_(3) to form CaFe_(2.O_(4).With the expansion of the diffusion region,the sillico-ferrite of calcium liquid phase was produced due to the melting of SiO_(2. into CaFe_(2.O_(4),which can strengthen the consolidation of fluxed ***,andradite would be formed around a small part of quartz particles,which is also conducive to the consolidation of fluxed *** addition,the principle diagram of limestone and quartz diffusion reaction in the process of fluxed pellet roasting was discussed.

关键词： fluxed iron ore pellet limestone hematite quartz diffusion reaction

Artificial intelligence optimization and controllable slow-release iron sulfide realizes efficient separation of copper and arsenic in strongly acidic wastewater

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Journal of Environmental Sciences 2024年第5期139卷 293-307页

作者： Xingfei zhang Chenglong Lu Jia Tian Liqiang Zeng Yufeng {1. Wei Sun Haisheng Han Jianhua Kang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Centre for Mined Land Rehabilitation Sustainable Minerals InstituteThe University of QueenslandBrisbane 4072Australia

Iron sulfide(FeS)is a promising material for separating copper and arsenic from strongly acidic wastewater due to its S^(2.)slow-release ***,uncertainties arise because of the constant changes in wastewater composition,affecting the selection of operating parameters and FeS *** this study,the aging method was first used to prepare various controllable FeS nanoparticles to weaken the arsenic removal ability without affecting the copper *** experiments were conducted,and the results identified the Cu/As ratio,H_(2.SO_(4) concentration,and FeS dosage as the three main factors influencing the separation *** backpropagation artificial neural network(BP-ANN)model was established to determine the relationship between the influencing factors and the separation *** correlation coefficient(R)of overall model was 0.992. after optimizing using genetic algorithm(GA).The BP-GA model was also solved using GA under specific constraints,predicting the best solution for the separation process in *** predicted results show that the high temperature and long aging time of FeS were necessary to gain high separation efficiency,and the maximum separation factor can reached 1.*** study provides a suitable sulfurizing material and a set of methods and models with robust flexibility that can successfully predict the separation efficiency of copper and arsenic from highly acidic environments.

关键词： FeS nanoparticles Aging Sulfide precipitation Orthogonal experiment Artificial neural network Prediction

Heterogeneous expression of stearoyl-acyl carrier protein desaturase genes SAD1.and SAD2.from Linum usitatissimum enhances seed oleic acid accumulation and seedling cold and drought tolerance in Brassica napus

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Journal of Integrative Agriculture 2024年第6期23卷 1864-1878页

作者： Jianjun wang Yanan Shao Xin Yang Chi {1. Yuan Guo Zijin Liu Mingxun Chen State Key Laboratory of Crop Stress Biology for Arid Areas/National Yangling Agricultural Biotechnology&Breeding Center/Shaanxi Key Laboratory of Crop Heterosis/College of Agronomy Northwest A&F UniversityYangling 712100China

Flax(Linum usitatissimum L.)is a versatile crop and its seeds are a major source of unsaturated fatty ***-acyl carrier protein desaturase(SAD)is a dehydrogenase enzyme that plays a key role in oleic acid biosynthesis as well as responses to biotic and abiotic ***,the function of SAD orthologs from *** has not been ***,we found that two LuSAD genes,LuSAD1.and LuSAD2.are present in the genome of *** cultivar‘Longya 1.’.Heterogeneous expression of either LuSAD1.or LuSAD2.in Arabidopsis thaliana resulted in higher contents of total fatty acids and oleic acid in the ***,ectopic expression of LuSAD2.in *** caused altered plant ***,the overexpression of either LuSAD1.or LuSAD2.in Brassica napus also resulted in increased contents of total fatty acids and oleic acid in the ***,we demonstrated that either LuSAD1.or LuSAD2.enhances seedling resistance to cold and drought stresses by improving antioxidant enzyme activity and nonenzymatic antioxidant levels,as well as reducing membrane *** findings not only broaden our knowledge of the LuSAD functions in plants,but also offer promising targets for improving the quantity and quality of oil,and the abiotic stress tolerance of oil-producing crops,through molecular manipulation.

关键词： LuSAD oleic acid cold tolerance drought tolerance Linum usitatissimum Brassica napus