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A density functional theory study on the interaction between UO_2^(2+) and the carbamoylphosphoramidic acid ligand for uranium extraction from seawater

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Nuclear Science and Techniques 2018年第6期29卷 128-140页

作者： Xiao-Jing Guo Cheng Li Jiang-Tao Hu Hong-juan ma Hong-Liang Qian Shanghai Institute of Applied Physics Chinese Academy of Sciences School of Engineering China Pharmaceutical University

Phosphorylurea molecules, which contain both phosphoryl and carbonyl groups, are considered efficient extractants for UO_2^(2+). This study aims to explain the complexation of UO_2^(2+)with carbamoylphosphoramidic acid(CPO), a simple model for phosphorylurea, for ligand design for uranium recovery from seawater using density functional theory calculations, natural bond order analysis,and the quantum theory of atoms in molecules. The results showed that, when CPO acts as a monodentate ligand, the affinity of phosphoryl for UO_2^(2+)is stronger than that of carbonyl, and CPO coordinates with UO_2^(2+)through the phosphoryl oxygen atom. When CPO serves as a bidentate ligand, both the phosphoryl and carbonyl oxygen atoms connect to UO_2^(2+), and the U–O(carbonyl) bond plays a more important role than the U–O(phosphoryl) bond in the interaction between UO_2^(2+)and CPO. This paradox may be caused by the significant charge transfer from the U–O(carbonyl) p bond orbital to the C–N σ antibond orbital of the bidentate CPO. The NH spacer between the phosphoryl and carbonyl groups could ensure the delocalization of the electron system of the molecule. The bidentate binding motif is favored by entropy and opposed by enthalpy, while the monodentate binding motif is favored by enthalpy and opposed by entropy. Ultimately, the bidentate binding motif is more favorable than the monodentate one. As expected, the interaction between UO_2^(2+)and the deprotonated CPO is stronger than that between UO_2^(2+)and the neutral CPO. Comparing the interaction between UO_2^(2+)and CPO with that between UO_2^(2+)and Nphenylcarbamoylphosphoramidic acid(Ph CPO), formed by replacing one hydrogen atom from the terminal nitrogen atom of CPO with a phenyl group, the phenyl substituent at the terminal nitrogen atom of Ph CPO shows a slightly negative effect on the interaction between UO_2^(2+)and Ph CPO.

关键词：相互作用理论学习海水密度抽取 CPO 铀苯基取代

牛粪和核桃果枝混合发酵理化特性试验及设备工艺优化

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新疆农机化 2024年第3期 30-34页

作者：赵超安世官孔令卓喻晨马娟新疆农业科学院农业机械化研究所新疆乌鲁木齐830091

通过鲜牛粪、牛粪与核桃果枝、牛粪核桃果枝加发酵菌剂三个不同配比的堆肥试验,开展牛粪和核桃果枝的化学特性参数试验;同时,参照土壤力学试验方法,对有机肥发酵各阶段的含水率、电导率、硬度、湿密度、抗剪强度等物理特性参数进行试验... 详细信息

通过鲜牛粪、牛粪与核桃果枝、牛粪核桃果枝加发酵菌剂三个不同配比的堆肥试验,开展牛粪和核桃果枝的化学特性参数试验;同时,参照土壤力学试验方法,对有机肥发酵各阶段的含水率、电导率、硬度、湿密度、抗剪强度等物理特性参数进行试验研究。试验结果表明,三种堆体有机质质量分数、总氮、总磷和总钾质量分数在堆肥初期都有所下降,随后缓慢上升,最后趋于平稳,分别稳定在32%、39%、40%,6.33%、9.48%、9.53%,0.95%、1.26%、1.29%和1.71%、2.59%、2.48%,添加果枝和菌剂的堆肥营养物质损失最少。三个堆体EC值的变化趋势基本一致,逐步升高,随着CO_(2)、NH_(3)的挥发,EC值开始缓慢下降,三个堆体EC值最终分别稳定在5.44ms/cm、5.94ms/cm、5.54ms/cm。3个堆体的湿密度在堆肥过程中都随着堆肥天数的增加总体呈下降趋势,堆肥结束时,三个堆体湿密度分别是0.71g/cm^(3)、0.65g/cm^(3)、0.45g/cm^(3)。

关键词：牛粪发酵工艺理化特性抗剪强度

基于核酸靶标免扩增CRISPR/Cas体系的分子速测技术研究进展

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中国生物工程杂志 2024年第6期44卷 104-115页

作者：李柚张岩雒嘉炜徐丹红马娟高梦祥刘华曾海娟王金斌长江大学生命科学学院荆州434022 上海市农业科学院生物技术研究所农业农村部农业转基因生物安全评价(环境)重点实验室上海201106

快速准确的分子诊断在食品安全、疾病诊断、环境监测等生命科学领域发挥重要作用。成簇规则间隔短回文重复序列(clustered regularly interspaced short palindromic repeats,CRISPR)及相关蛋白(CRISPR-associated protein,Cas)组成的CRISPR/Cas系统因具有高灵敏度、高特异性、便捷性及快速等优势,已成为精确检测核酸靶标的重要分子诊断工具。基于CRISPR/Cas系统的检测通过预扩增步骤提高靶标浓度,但也随之带来气溶胶污染、操作复杂和检测周期长等问题。因此需要积极开发更多免扩增策略,在最大限度保证灵敏度的同时,一步式实现对靶标的检测。综述了免扩增CRISPR系统的重要性,重点阐述了反应影响因素及相关策略对体系的优化作用,以及数字芯片法、表面增强拉曼光谱法和电化学金属电极法对信号放大效果的前沿进展,并对CRISPR/Cas系统的即时检测应用进行展望,以期为免扩增CRISPR/Cas检测系统的发展提供理论指导。

关键词：成簇规则间隔短回文重复序列(CRISPR) 免扩增检测体系优化信号放大

基于土柱模拟降雨对铜尾矿重金属淋溶进入下伏土壤的生态风险研究

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河南师范大学学报（自然科学版） 2024年第3期52卷 119-130页

作者：贺婧金安妮张扣扣马娟罗玲玲任惠芹钟艳霞宁夏大学西北土地退化与生态恢复国家重点实验室培育基地银川750021 宁夏大学生态环境学院银川750021 宁夏大学地理科学与规划学院银川750021 宁夏回族自治区生态环境监测中心银川750002

为探究铜尾矿重金属释放对环境的影响,通过动态淋溶实验,配置初始pH=7.2的人工模拟雨水为淋滤液,采用柱状淋溶装置进行尾矿重金属淋出实验,探究中卫某铜尾矿重金属的淋溶释放特征,评估尾矿重金属淋溶的生态风险.结果表明,尾矿中Cu、Zn... 详细信息

为探究铜尾矿重金属释放对环境的影响,通过动态淋溶实验,配置初始pH=7.2的人工模拟雨水为淋滤液,采用柱状淋溶装置进行尾矿重金属淋出实验,探究中卫某铜尾矿重金属的淋溶释放特征,评估尾矿重金属淋溶的生态风险.结果表明,尾矿中Cu、Zn、As、Cd和Pb平均质量含量分别为2130.30、105.10、234.41、0.72和64.57mg·kg^(-1),均超出宁夏土壤重金属元素背景值.淋溶10次后,尾矿中Cd、Zn、Pb、As、Cu等重金属的释放率分别为1.98%、0.32%、0.30%、0.15%、0.01%,即Cd的释放率最高.淋溶后,尾矿重金属质量含量明显下降,其中0~5cm深度尾矿重金属含量下降最多,As的释放量最大,重金属向下层迁移明显.尾矿中Cu、Pb、Cd和Zn主要淋失碳酸盐结合态,As主要淋失可交换态,As和Cd的淋溶风险较高.Cu是尾矿重金属中关键的生态风险因子,尾矿中Cd和Cu为高风险,As、Zn和Pb为中风险.

关键词：铜尾矿重金属淋溶生态风险

长期卧床患者肺部感染危险因素及其TLR7 mRNA和IL-23与IL-17的预测价值

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中华医院感染学杂志 2024年第4期34卷 503-507页

作者：黄艳马乐娟邢冬钱万峰寿月华沈海良绍兴文理学院附属医院护理部浙江绍兴321000 绍兴文理学院附属医院院感处浙江绍兴321000 绍兴文理学院附属医院骨科浙江绍兴321000 绍兴文理学院附属医院综合康复科浙江绍兴321000

目的脊柱手术后长期卧床患者肺部感染患者危险因素及其Toll样受体7(TLR7)和白细胞介素-23(IL-23)与IL-17信号通路的预测价值.方法收集2019年1月—2022年9月绍兴文理学院附属医院收治的脊柱手术后长期卧床未并发肺部感染患者123例设为未... 详细信息

目的脊柱手术后长期卧床患者肺部感染患者危险因素及其Toll样受体7(TLR7)和白细胞介素-23(IL-23)与IL-17信号通路的预测价值.方法收集2019年1月—2022年9月绍兴文理学院附属医院收治的脊柱手术后长期卧床未并发肺部感染患者123例设为未感染组,选取同期于医院接受治疗的33例脊柱手术后长期卧床并发肺部感染患者作为感染组,采用多因素Logistic回归分析归纳脊柱手术后长期卧床患者肺部感染的危险因素,采用受试者工作特征(ROC)曲线分析TLR7、IL-23、IL-17信号通路对脊柱手术后长期卧床患者肺部感染的预测价值.结果多因素Logistic回归分析结果显示,慢性肺部疾病、合并糖尿病、机械通气均为脊柱手术后长期卧床患者肺部感染的危险因素(OR=3.323,2.646,2.259,P<0.05);联合预测脊柱手术后长期卧床患者肺部感染发生的曲线下面积(AUC)值均高于TLR7 mRNA、IL-23、IL-17单独检测(P<0.05);TLR7 mRNA及联合敏感度高于IL-23、IL-17(P<0.05);IL-23及联合检测特异度高于TLR7 mRNA、IL-17(P<0.05),IL-17特异度高于TLR7 mRNA(P<0.05).结论脊柱手术后长期卧床患者肺部感染发生的易感因素包括有慢性肺部疾病、合并糖尿病、机械通气,同时TLR7/IL-23/IL-17信号通路相关指标联合检测对脊柱手术后长期卧床患者肺部感染发生具有较好的预测价值,临床可根据其相关易感因素和保护因素对脊柱手术后长期卧床患者进行针对性干预或治疗,降低患者肺部感染发生的风险.

关键词：脊柱手术长期卧床肺部感染易感因素 Toll样受体7 白细胞介素-23 白细胞介素-17 信号通路预测价值

营养干预联合抗阻运动对脑卒中继发性肌少症患者的影响

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中国疗养医学 2024年第1期33卷 38-41页

作者：梁碧娟李华代林玲李蕊马继娟苏建培昆明市第二人民医院云南昆明650204

目的探析营养干预联合抗阻运动在脑卒中继发性肌少症中的应用价值。方法采用目的抽样法,选取2022年8月至2023年2月在昆明市第二人民医院老年病科收治的50例缺血性脑卒中继发性肌少症患者作为研究对象,根据病案号个位数,按奇偶数将参与... 详细信息

目的探析营养干预联合抗阻运动在脑卒中继发性肌少症中的应用价值。方法采用目的抽样法,选取2022年8月至2023年2月在昆明市第二人民医院老年病科收治的50例缺血性脑卒中继发性肌少症患者作为研究对象,根据病案号个位数,按奇偶数将参与研究的对象随机分为观察组(n=25)与对照组(n=25)。两组均维持慢性病常规药物治疗。对照组采用常规饮食、传统康复锻炼,观察组在对照组基础上予以营养干预联合抗阻运动。干预前后分别测定患者血清白蛋白(albumin,ALB)、血红蛋白(hemoglobin,Hb)及维生素D(vitamin D,VD)水平;运用整体营养评定量表(patient generated-subjective global assessment,PG-SGA)及改良Barthel指数量表评定营养状况及日常生活能力。结果两组患者一般资料比较差异无统计学意义(P>0.05)。观察组患者Hb、ALB及VD分别为(128.32±14.49)g/L、(38.46±6.01)g/L、(25.89±6.71)ng/mL,高于对照组(120.07±11.32)g/L、(34.09±5.89)g/L、(21.34±7.01)ng/mL,PG-SGA评分(2.04±0.91)分低于对照组(5.05±1.16)分,差异有统计学意义(P<0.05);观察组患者日常生活能力评分高于对照组,差异有统计学意义(P<0.05)。结论营养干预联合抗阻运动可快速恢复脑卒中继发性肌少症患者营养水平,并提高其日常生活活动能力。

关键词：营养干预抗阻运动脑卒中继发性肌少症营养水平日常生活能力

A hybrid method for inverse cavity scattering problem for shape

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Applied mathematics(A Journal of Chinese Universities) 2010年第2期25卷 127-136页

作者： LIU juan ma Fu-ming School of mathematics, Jilin University, Changchun 130012, China. School of mathematics Jilin University Changchun China

In this paper, we give a hybrid method to numerically solve the inverse open cavity scattering problem for cavity shape, given the scattered solution on the opening of the cavity. This method is a hybrid between an iterative method and an integral equations method for solving the Cauchy problem. The idea of this hybrid method is simple, the operation is easy, and the computation cost is small. Numerical experiments show the feasibility of this method, even for cases with noise.

关键词： Open cavity Cauchy problem Helmholtz equation integral equations system method iterativehybrid method.

Creatine Pyruvate Enhances Lipolysis and Protein Synthesis in Broiler Chicken

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Agricultural Sciences in China 2011年第12期10卷 1977-1985页

作者： CHEN juan ma Hai-tian WANG man KONG Yi-li ZOU Si-xiang Key Laboratory of Animal Physiology ＆ Biochemistry College of Veterinary Medicine Nanjing Agricultural University Nanjing 210095 P.R. China

To assess the effects ofcreatine pyruvate （Cr-Pyr） on lipid and protein metabolism in broiler chickens, a total of 400 1-day-old male birds （Aconred） were randomly allocated to four groups, with each group replicating four times and each replicate involving 25 birds. The broilers were provided with a commercial diet supplemented with Cr-Pyr at 0, 1, 5, or 10% of the diet, respectively, for a period of 3 wk ad libitum （from 22 to 42 d）. In the present study, body weight （BW） and average daily gain （ADG） of broilers decreased in 10% Cr-Pyr group （P〈0.01）, whereas the relative leg and pectoral muscle weights were significantly higher than they were in the control group （P〈0.05）. 5 or 10% Cr-Pyr of diets decreased the abdominal fat rate （AFR, abdominal fat/live weight） of the broilers. The serum or hepatic triglyceride （TG） concentrations were significantly lower in the 5 and 10% groups （P〈0.01）. In contrast, Cr-Pyr caused a marked increase in the serum nonesterified fatty acid （NEFA）, high-density lipoprotein cholesterol （HDL-C） and creatine kinase （CK） concentrations （P〈0.01）. Supplementation with Cr-Pyr （5 and 10%） in the diet also increased glucagons （GLU）, insulin （INS） or leptin （LEP） contents （P〈0.01）. The expression of hepatic peroxisomal proliferators-activated receptor α （PPAR-α） and carnitine palmitoyl transferase-I （CPT-I）, muscle insulin-like growth factor I （IGF-I） were significantly elevated and myostatin mRNA level was reduced in the 5 and 10% groups （P〈0.05）. It was found that supplementation with 5% Cr-Pyr improves both lipid and protein metabolism by regulating various metabolic parameters of broilers, while not adversely affects growth performance in broiler chickens.

关键词： creatine pyruvate (Cr-Pyr) lipid metabolism protein metabolism liver muscle broiler chickens

New Year's greeting and overview of World Journal of Cardiology in 2021

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World Journal of Cardiology 2021年第2期13卷 38-41页

作者： Ya-juan ma Ramdas G Pai Editorial Office Baishideng Publishing Group IncPleasantonCA 94566United States University of California Riverside School of Medicine St Bernardines Medical CenterRiversideCA 92507United States

On behalf of the Editorial Office of World Journal of Cardiology(WJC),we extend our sincere gratitude to our authors,readers,Editorial Board members,and peer reviewers,thanking each and every one for their contributions to WJC in 2020 and with wishes for a Happy New *** was the collective support of all authors,Editorial Board members,peer reviewers and staff of the Editorial Office that allowed the Baishideng Publishing Group *** carry out successfully the complete peer review,editing and publishing processes for WJC in *** have now analyzed the metric data of WJC's manuscripts that were submitted and published in 2020,the peer review of manuscripts in 2020,the invited manuscripts for 2021 and the Editorial Board members’composition and *** a global academic journal in cardiology,the findings from such will facilitate greater productivity and more efficient collaborative efforts to raise the academic rank of WJC in *** enthusiastically anticipate WJC’s contributions to promote further cardiology research sharing and exchange in 2021.

关键词： World Journal of Cardiology Baishideng Editorial board members Cardiology New Year's message Academic rank