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Neural network study of the nuclear ground-state spin distribution within a random interaction ensemble

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Nuclear Science and Techniques 2024年第3期35卷 216-227页

作者： deng liu Alam Noor A Zhen-Zhen Qin Yang Lei School of Mathematics and Physics Southwest University of Science and TechnologyMianyang 621010China School of Nuclear Science and Technology Southwest University of Science and TechnologyMianyang 621010China

The distribution of the nuclear ground-state spin in a two-body random ensemble(TBRE)was studied using a general classification neural network(NN)model with two-body interaction matrix elements as input features and the corresponding ground-state spins as labels or output *** quantum many-body system problem exceeds the capability of our optimized NNs in terms of accurately predicting the ground-state spin of each sample within the ***,our NN model effectively captured the statistical properties of the ground-state spin because it learned the empirical regularity of the ground-state spin distribution in TBRE,as discovered by physicists.

关键词： Neural network Two-body random ensemble Spin distribution of nuclear ground state

A unified Minorization-Maximization approach for estimation of general mixture models

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 343-362页

作者： HUANG Xi-fen liu deng-ge ZHOU Yun-peng ZHU Fei School of Mathematics Yunnan Normal UniversityKunming 650092China Department of Statistics and Actuarial Science The University of Hong KongHong KongChina

The mixed distribution model is often used to extract information from heteroge-neous data and perform modeling *** the density function of mixed distribution is complicated or the variable dimension is high,it usually brings challenges to the parameter es-timation of the mixed distribution *** application of MM algorithm can avoid complex expectation calculations,and can also solve the problem of high-dimensional optimization by decomposing the objective *** this paper,MM algorithm is applied to the parameter estimation problem of mixed distribution *** method of assembly and decomposition is used to construct the substitute function with separable parameters,which avoids the problems of complex expectation calculations and the inversion of high-dimensional matrices.

关键词： MM algorithm mixed distribution model parameter estimation assembly decomposition tech-nology parameter separation

Microbially-mediated formation of Ca-Fe carbonates during dissimilatory ferrihydrite reduction:Implications for the origin of sedimentary ankerite

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Science China Earth Sciences 2024年第1期67卷 208-221页

作者： deng liu Jinpeng CAO Shanshan YANG Yating YIN Pengcong WANG Dominic PAPINEAU Hongmei WANG Xuan QIU Genming LUO Zongmin ZHU Fengping WANG State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China School of Environmental Studies China University of GeosciencesWuhan 430074China London Centre for Nanotechnology University College LondonLondon WC1H 0AHUK Department of Earth Sciences University College LondonLondon WC1E 6BTUK Center for Planetary Sciences University College London and Birkbeck College LondonLondon WC1E 6BTUK State Key Laboratory of Microbial Metabolism State Key Laboratory of Ocean EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The origin of sedimentary dolomite has become a long-standing problem in the Earth *** carbonate minerals like ankerite have the same crystal structure as dolomite,hence their genesis may provide clues to help solving the dolomite *** purpose of this study was to probe whether microbial activity can be involved in the formation of ***-carbonation experiments associated with microbial iron reduction were performed in batch systems with various concentrations of Ca^(2+)(0–20 mmol/L),with a marine iron-reducing bacterium Shewanella piezotolerans WP3 as the reaction mediator,and with lactate and ferrihydrite as the respective electron donor and *** biomineralization data showed that Ca-amendments expedited microbially-mediated ferrihydrite reduction by enhancing the adhesion between WP3 cells and ferrihydrite *** bioreduction,siderite occurred as the principal secondary mineral in the Ca-free ***,Ca-Fe carbonates were formed when Ca^(2+)ions were *** CaCO_(3) content of microbially-induced Ca-Fe carbonates was positively correlated with the initial Ca2+*** Ca-Fe carbonate phase produced in the 20 mmol/L Ca-amended biosystems had a chemical formula of Ca_(0.8)Fe_(1.2)(CO_(3))_(2),which is close to the theoretical composition of *** ankeritelike phase was nanometric in size and spherical,Ca-Fe disordered,and structurally *** simulated diagenesis experiments further demonstrated that the resulting ankerite-like phase could be converted into ordered ankerite under hydrothermal *** introduced the term“proto-ankerite”to define the Ca-Fe phases that possess near-ankerite stoichiometry but disordered cation *** the basis of the present study,we proposed herein that microbial activity is an important contributor to the genesis of sedimentary ankerite by providing the metastable Ca-Fe carbonate precursors.

关键词： Ankerite Proto-ankerite Microbial iron reduction Dolomite problem Mineral transformation

Increased Expression of Serum Monocyte Chemoattractant Protein-1,Chemokine(C-C motif)Ligand 3,and Interleukins in Patients With Vitiligo

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International Journal of Dermatology and Venereology 2024年第1期7卷 40-43页

作者： Xiao-Ling Zhao Ya-Lan Li Zi-Han Li Xiao-Chong Zhang Li-Hui An Yu-Jiao Sun deng-Xiang liu Fang Cheng Cancer Laboratory Xingtai People’s HospitalXingtaiHebei 054001China Endocrine Department Xingtai People’s HospitalXingtaiHebei 130500China Dermatological Department Xingtai People’s HospitalXingtaiHebei 054001China

Objective:Vitiligo is a chronic,acquired depigmentation of the skin,which can be divided into active and stable *** stable and active stages are not immutable and often *** of internal markers would help to diagnose the active stage of vitiligo,and the purpose of this study was to find potential active markers in the progression of ***:We compared 30 healthy controls to 60 patients with vitiligo(30 with active disease and 30 with stable disease)regarding the expression of serum monocyte chemoattractant protein(MCP)-1,chemokine(C-C motif)ligand(CCL)3,CCL5,CCL21,interleukin(IL)-6,and *** were collected from May 2017 to December *** detection was carried out by enzyme-linked immunosorbent *** difference between groups was compared by Kruskal-Wallis H test and Mann-Whitney U ***:We found that the serum levels of MCP-1,CCL3,IL-6,and IL-17 were significantly higher in patients with vitiligo than in healthy controls(P<0.01)and that IL-17 was higher in patients with active vitiligo than in those with stable vitiligo(P<0.01).After 3months of treatment,the serum IL-17 level of patients with active vitiligo was not significantly different from that before treatment(P=0.526);after 6months of treatment,however,the serum IL-17 level had significantly decreased(P<0.01).Conclusion:These findings suggest that the serum IL-17 level can be used as a marker of vitiligo disease activity giving it certain guiding significance for clinical treatment.

关键词： clinical marker serum cytokines vitiligo

细胞表面显示技术在纤维素乙醇制备中的应用及挑战

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现代化工 2024年第8期44卷 75-79,85页

作者：刘登山东理工职业学院能源与材料工程学院山东济宁272067

简单介绍了细胞表面显示技术的设计原理,归纳了细胞表面显示技术在纤维素乙醇生产中的技术优势和应用价值,重点讨论了细胞表面显示技术在纤维素乙醇制备中存在的技术障碍。最后,总结了细胞表面显示技术在纤维素乙醇生产中的实用意义,提... 详细信息

简单介绍了细胞表面显示技术的设计原理,归纳了细胞表面显示技术在纤维素乙醇生产中的技术优势和应用价值,重点讨论了细胞表面显示技术在纤维素乙醇制备中存在的技术障碍。最后,总结了细胞表面显示技术在纤维素乙醇生产中的实用意义,提出了面临的问题并展望了其应用前景。

关键词：纤维素乙醇细胞表面显示技术全细胞催化剂酵母综合生物工艺

难治性肺炎支原体肺炎患儿并发闭塞性细支气管炎风险预测模型的构建

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中国当代儿科杂志 2024年第9期26卷 946-953页

作者：刘铁虎刘小雪汤洋齐飞刘登品湘雅常德医院儿科广西师范大学数学与统计学院

目的探讨难治性肺炎支原体肺炎（refractory Mycoplasma pneumoniae pneumonia, RMPP）患儿并发闭塞性细支气管炎（bronchiolitis obliterans, BO）风险预测模型的建立。方法回顾性纳入2021年6月—2023年12月湘雅常德医院儿科收治的11... 详细信息

目的探讨难治性肺炎支原体肺炎（refractory Mycoplasma pneumoniae pneumonia, RMPP）患儿并发闭塞性细支气管炎（bronchiolitis obliterans, BO）风险预测模型的建立。方法回顾性纳入2021年6月—2023年12月湘雅常德医院儿科收治的116例RMPP患儿为研究对象，按照7∶3的比例，81例分到训练集，35例分到验证集。其中训练集发生BO 26例，未发生BO 55例。采用多因素logistic回归筛选变量构建BO的风险预测模型，并绘制列线图。使用受试者操作特征曲线（receiver operating characteristic curve, ROC曲线）评估预测模型的区分度，采用校准度曲线和Hosmer-Lemeshow检验评估预测模型的校准度。结果多因素logistic回归分析显示，住院时间、发热持续时间、肺不张、中性粒细胞百分比（neutrophil percentage, NEUT%）、乳酸脱氢酶（lactate dehydrogenase, LDH）峰值、铁蛋白、C反应蛋白（C reactive protein, CRP）峰值、氧合指数（oxygenation index,PaO2/FiO2）、≥2/3肺叶实变、胸腔积液、支气管黏液栓、支气管黏膜坏死、动脉血氧分压（arterial oxygen partial pressure, PaO2）与RMPP患儿并发BO密切相关（P<0.05）。多因素logistic回归模型预测训练集RMPP患儿并发BO的ROC曲线分析显示曲线下面积为0.904，灵敏度为88%，特异度为83%；验证集RMPP患儿并发BO的ROC曲线分析显示曲线下面积为0.823，灵敏度为76%，特异度为93%。多因素logistic回归模型预测训练集和验证集RMPP患儿并发BO的Hosmer-Lemeshow检验的卡方统计量分别为2.17、1.92,P值分别为0.221、0.196。结论基于logistic回归模型构建的RMPP患儿并发BO的风险预测模型具有良好的性能；住院时间、发热持续时间、肺不张、LDH峰值、CRP峰值、NEUT%、铁蛋白、≥2/3肺叶实变、胸腔积液、支气管黏液栓、支气管黏膜坏死、PaO2/FiO2、PaO2等指标可作为预测变量。[中国当代儿科杂志，2024,26 （9）:946-953]

关键词：难治性肺炎支原体肺炎闭塞性细支气管炎风险预测模型儿童

新课程背景下素养立意的表现性评价设计:内涵、价值与路径

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教育理论与实践 2024年第5期44卷 15-20页

作者：刘登珲牛文琪江南大学教育学院江苏无锡214122

核心素养的有效培育呼唤素养立意的表现性评价设计。作为新课程标准境脉下课堂评价方式变革的路向,素养立意的表现性评价与核心素养内在特质相契合,具有一致性、发展性、参与性、真实性、结构性等特点,在促进素养目标持续进阶、实现学... 详细信息

核心素养的有效培育呼唤素养立意的表现性评价设计。作为新课程标准境脉下课堂评价方式变革的路向,素养立意的表现性评价与核心素养内在特质相契合,具有一致性、发展性、参与性、真实性、结构性等特点,在促进素养目标持续进阶、实现学习持续增值、减负增效以及破解课堂变革“最后一公里”难题上有重要价值。素养立意的表现性评价设计可以通过明晰素养目标,制定表现标准;确立证据与完善标准,设计表现任务;制定评分规则,收集表现证据;研判表现证据,反馈结果信息来实现。素养立意的表现性评价弥散在学习的全过程,因而具有复杂性、易变性特质,教师只有持续提升评价素养、强化设计意识、超越线性思维,才能真正促进核心素养落地生根。

关键词：新课程素养立意表现性评价学生评价学习过程

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地球熔岩管道微生物研究对天体生物学的启示

微生物学报 2024年第6期64卷 1922-1935页

作者：程晓钰李旻肖龙刘邓王红梅中国地质大学(武汉)生物地质与环境地质国家重点实验室湖北武汉430078 中国地质大学(武汉)环境学院湖北武汉430078 中国地质大学(武汉)地球科学学院湖北武汉430074

天体生物学作为与深空探测相结合的交叉学科,旨在从地球极端环境类比、古代生命载体信息发掘和模拟等方面揭示地外行星体是否适合生命生存和繁衍,其中适宜的环境条件是评价所有天体是否宜居的重要条件。近年来在月球和火星等行星表面发... 详细信息

天体生物学作为与深空探测相结合的交叉学科,旨在从地球极端环境类比、古代生命载体信息发掘和模拟等方面揭示地外行星体是否适合生命生存和繁衍,其中适宜的环境条件是评价所有天体是否宜居的重要条件。近年来在月球和火星等行星表面发现了大量由火山熔岩流形成的熔岩管道,这些巨型管状地下空间具有稳定的温度和防辐射等环境条件,为生物在地外星体上的生存提供了潜在的庇护场所。基于地球熔岩管道的天体生物学的类比研究可以为探索地外生命痕迹提供重要线索,本文综述了现阶段地球熔岩管道内微生物的研究进展、微生物痕量气体代谢在天体生物学研究中的潜力及天体生物学的研究进展,旨在为后续开展地球及地外熔岩管道的天体生物学研究提供思路。

关键词：天体生物学熔岩管道极端微生物能量代谢方式月球火星

W-Ni_(2)P@NiFe LDH/NF的合成及其用于高效电催化析氧研究

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现代化工 2024年第1期44卷 183-187页

作者：刘文辉段永明王宏伟侯玉龙王琨刘登登中北大学环境与安全工程学院山西太原030051 山西柴油机工业有限责任公司山西大同037036

以NiFe LDH微米级小球为骨架支撑,原位生长W掺杂Ni_(2)P纳米片,形成了以NiFe LDH为核､W-Ni_(2)P为壳的独特纳米阵列,并通过SEM､XRD和电化学催化性能测试等手段对W-Ni_(2)P@NiFe LDH/NF的形貌､结构和电化学性能进行分析。结果表明,W-Ni_(... 详细信息

以NiFe LDH微米级小球为骨架支撑,原位生长W掺杂Ni_(2)P纳米片,形成了以NiFe LDH为核､W-Ni_(2)P为壳的独特纳米阵列,并通过SEM､XRD和电化学催化性能测试等手段对W-Ni_(2)P@NiFe LDH/NF的形貌､结构和电化学性能进行分析。结果表明,W-Ni_(2)P@NiFe LDH/NF独特的三维球状纳米结构加快了电荷转移速率,提供了丰富的活性位点,并在W-Ni_(2)P与NiFe LDH之间产生协同效应,提高了析氧反应的电催化性能和耐久性。与Ni_(2)P和NiFe LDH相比,球状结构W-Ni_(2)P@NiFe LDH/NF表现出优异的OER性能,在电流密度为40 mA/cm^(2)时,过电势仅为251 mV;Tafel斜率仅为52 mV/dec;电化学阻抗最小;Cdl值为3.51 mF/cm^(2),且维持电流密度23 mA/cm^(2)超过10 h无明显的下降趋势。

关键词：原位生长电化学性能析氧反应