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Chinese Chemical Letters 2024年第2期35卷 411-414页

作者： sen qiao Kunquan Chen Qiang Liu Zhixiang Wang Xiangyu Chen School of Chemical Sciences University of the Chinese Academy of SciencesBeijing 100049China Binzhou Institute of Technology Weiqiao-UCAS Science and Technology ParkBinzhou 256606China

A charge transfer complex(CTC)-enabled photoreduction of ether phosphonium salts for the generation of oxyalkyl radicals was described.The photoreduction provides a convenient method to achieve selective oxyalkylation of enamides with broad substrate scope.The method features operational simplicity,mild and inherent green conditions.

关键词： Enamides Phosphonium salts Ethers Charge transfer complex Visible light

Cooperative Covert Communication in Multi-Antenna Broadcast Channels

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China Communications 2024年第6期21卷 246-260页

作者： qiao sen Liu Guangjie Ji Xiaopeng Liu Weiwei School of Electrical and Information Engineering Nanjing University of Information Science and TechnologyNanjing 210044China School of Automation Nanjing University of Science and TechnologyNanjing 210094China

With the gradual popularization of 5G communications,the application of multi-antenna broadcasting technology has become widespread.Therefore,this study aims to investigate the wireless covert communication in the two-user cooperative multi-antenna broadcast channel.We focus on the issue that the deteriorated reliability and undetectability are mainly affected by the transmission power.To tackle this issue,we design a scheme based on beamforming to increase the reliability and undetectability of wireless covert communication in the multi-antenna broadcast channel.We first modeled and analyzed the cooperative multi-antenna broadcasting system,and put forward the target question.Then we use the SCA(successive convex approximation)algorithm to transform the target problem into a series of convex subproblems.Then the convex problems are solved and the covert channel capacity is calculated.In order to verify the effectiveness of the scheme,we conducted simulation verification.The simulation results show that the proposed beamforming scheme can effectively improve the reliability and undetectability of covert communication in multi-antenna broadcast channels.

关键词： beamforming covert communication multi-antenna broadcast channels OFDM

Sulfide-driven nitrous oxide recovery during the mixotrophic denitrification process

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Journal of Environmental Sciences 2023年第3期125卷 443-452页

作者： Cong Yu sen qiao Jiti Zhou Key Laboratory of Industrial Ecology and Environmental Engineering(Ministry of Education China)School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China

We propose a novel sulfide-driven process to recover N_(2)O during the traditional denitrification process.The optimum initial sulfide concentration was 120 mg/L,and the N_(2)O percentage in the gaseous products (N_(2)O+N_(2)) was up to 82.9%.Moreover,sulfide involved in denitrification processes could substitute for organic carbon as an electron donor,e.g.,1g sulfide was equivalent to 0.5-2 g COD when sulfide was oxidized to sulfur and sulfate.The accumulation of N_(2)O was mainly due to the inhibiting effect of sulfide on nitrous oxide reductase (N_(2)OR),which was induced by the supply insufficiency of electrons from cytochrome c (cyt c) to N_(2)OR.When the initial sulfide concentration was 120 mg/L,the N_(2)OR activity was only 36.8%of its original level.According to the results of cyclic voltammetry,circular dichroism spectra and fluorescence spectra,significant changes in the conformations and protein structures of cyt c were caused by sulfide,and cyt c completely lost its electron transport capacity.This study provides a new concept for N_(2)O recovery driven by sulfide in the denitrification process.In addition,the findings regarding the mechanism of the inhibition of N_(2)OR activity have important implications both for reducing emissions of N_(2)O and recovering N_(2)O in the sulfide-driven denitrification process.

关键词： N_(2)O recovery N_(2)OR inhibition Cytochrome c Electron transfer capacity

Mechanism Exploration of Euphorbia fischeriana Steud. for Liver Cancer Based on Aspartic Acid Identification in Metabolomics

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Chinese Journal of Integrative Medicine 2024年第6期30卷 507-514页

作者： ZHAO Jing TIAN Xin-chen ZHANG Jia-qi HUANG Chen SUN Yan qiao sen JIANG Shu-long Clinical Medical Laboratory Center Jining First People’s HospitalJiningShandong Province272000China Cheeloo College of Medicine Shandong UniversityJinan250000China

Objective:To investigate the anti-liver cancer effects and aspartic acid(Asp)-related action mechanism of Euphorbia fischeriana Steud.(LD).Methods:The mice model of liver cancer was established by injection of H22 cells.After 5 days,mice were randomly divided into model group,sorafenib group(20 mg/kg),LD high-dose(LDH,1.36 g/kg) group,LD medium-dose(LDM,0.68 g/kg) group,and LD low-dose(LDL,0.34 g/kg)group,10 mice each group.Drugs were intragastrically administered to the mice once daily for 10 days,respectively.Body weight,tumor size and tumor weight were recorded.Hepatic index was calculated.Pathological changes of liver cancer tissues were evaluated by hematoxylin and eosin staining and TUNEL staining.Liquid chromatography-mass spectrometer was used to analyze different metabolites between the model and LDH groups.Results:After LD treatment,tumor weight,tumor size and hepatic index were reduced compared with the model group.Necrocytosis and karyorrhexis of tumor cells were found.Moreover,61 differential metabolites(18 up-regulated,43 down-regulated) were affirmed and 20 pathways of KEGG(P<0.05) were gotten.In addition,Bel-7402,HepG2 and H22 cell viabilities were significantly increased after adding Asp into the medium.And then,the cell proliferation effect induced by Asp was ameliorated by LD.Conclusion:The anti-liver cancer efficacy of LD extract was validated in H22 mice model,and inhibition of Asp level might be the underlying mechanism.

关键词： liver cancer Euphorbia fischeriana Steud. aspartic acid metabolomics

Simple chemical synthesis and isotropic negative thermal expansion in MHfF_(6)(M=Ca,Mn,Fe,and Co)

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Nano Research 2024年第3期17卷 2195-2203页

作者： Yongqiang qiao sen Zhang Peixian Zhang Juan Guo Andrea Sanson Xi Zhen Kaiyue Zhao Qilong Gao Jun Chen Key Laboratory of Materials Physics of Ministry of Education and School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China Department of Physics and Astronomy University of PadovaPadova I-35131Italy Beijing Advanced Innovation Center for Materials Genome Engineering Department of Physical ChemistryUniversity of Science and Technology BeijingBeijing 100083China

The rapid progress of modern technologies has accelerated the prominence of thermal expansion mismatch between materials,and tunable thermal expansion materials will be a powerful safeguard against this challenge.Here,isotropic MHfF_(6)(M=Ca,Mn,Fe,and Co)compounds with tunable thermal expansion have been produced via a low-cost synthetic method and investigated.By utilizing temperature dependent X-ray diffraction(XRD)and Raman spectroscopy,combined with first principles calculations,it was revealed that the transverse thermal vibrations of the F atoms are dominated by low-frequency phonons with negative Grüneisen parameters and are therefore the origin of the negative thermal expansion(NTE).Very interestingly,with the increase of the M atomic number,the metal…F atomic linkages become stiffer,reducing the number of vibrational modes with negative Grüneisen parameters,so that the strong NTE can be gradually adjusted to moderate NTE and to near zero thermal expansion.The present study achieves the tunable thermal expansion in a new compound family and shed light on the internal mechanism from the perspective of lattice vibrational dynamics.

关键词： negative thermal expansion fluorides chemical synthesis nanosheet structure first principles calculations

CoFe_(2)O_(4) decorated graphene/C_(18)-functionalized mesoporous silica nanocomposites prepared for magnetic enrichment and electrochemical detection of promethazine in beef

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Chinese Chemical Letters 2024年第3期35卷 208-213页

作者： Xingdong Yang Shi-Ming Ying sen Zhang Jinxia Dai Wei Gao Tian-Qi Wang Jun-Qin qiao Hong-Zhen Lian Li Mao State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry&Chemical Engineering and Centre of Materials AnalysisNanjing UniversityNanjing 210023China Ministry of Education(MOE)Key Laboratory of Modern Toxicology School of Public HealthNanjing Medical UniversityNanjing 211166China

Promethazine(PHZ)is used as a sedative in veterinary medicine,and its residue can threaten the health of human.The electrochemical detection of PHZ is suitable method for application in the field.However,the traditional electroanalysis is difficult to perform directly in meat samples due to matrix interference.This work integrates magnetic solid-phase extraction and differential pulse voltammetry for highly sensitive and selective determination of PHZ in beef and beef liver for the first time.CoFe_(2)O_(4)/graphene coated with C_(18)-functionalized mesoporous silica(MG@mSiO_(2)-C_(18))is synthesized as dispersed magnetic adsorbent to extract PHZ.Magnetic glassy carbon electrode modified with nitrogen-doped hollow carbon microspheres(HCM)attracts the MG@mSiO_(2)-C_(18)with PHZ,and directly detects the PHZ without elution procedure.MG@mSiO_(2)-C_(18)can separate PHZ to avoid the interference of impurities on following detection,and also concentrate PHZ on magnetic electrode.Additionally,the electrode modification with HCM can amplify the electrochemical signal of PHZ.Finally,the integrated PHZ determination method exhibits a wide linear range from 0.08μmol/L to 300μmol/L with a low limit of detection of 9.8 nmol/L.The beef sample analysis presents excellent recovery,demonstrating that this protocol is promising for the rapid and onsite detection of PHZ in real meat samples。

关键词： Promethazine(PHZ) Drug residue Magnetic solid phase extraction Electrochemical detection Beef

Emerging clinical relevance of microbiome in cancer:promising biomarkers and therapeutic targets

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Protein & Cell 2024年第4期15卷 239-260页

作者： Jia-Hao Dai Xi-Rong Tan Han qiao Na Liu State Key Laboratory of Oncology in South China Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapyGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510050China

The profound influence of microbiota in cancer initiation and progression has been under the spotlight for years,leading to numerous researches on cancer microbiome entering clinical evaluation.As promising biomarkers and therapeutic targets,the critical involvement of microbiota in cancer clinical practice has been increasingly appreciated.Here,recent progress in this field is reviewed.We describe the potential of tumor-associated microbiota as effective diagnostic and prognostic biomarkers,respectively.In addition,we highlight the relationship between microbiota and the therapeutic efficacy,toxicity,or side effects of commonly utilized treatments for cancer,including chemotherapy,radiotherapy,and immunotherapy.Given that microbial factors influence the cancer treatment outcome,we further summarize some dominating microbial interventions and discuss the hidden risks of these strategies.This review aims to provide an overview of the applications and advancements of microbes in cancer clinical relevance.

关键词： microbiome cancer diagnosis prognosis therapy

37例颞下颌关节盘不可复性前移位患者自然转归的临床及磁共振成像特征分析

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华西口腔医学杂志 2024年第1期42卷 82-88页

作者：闫森乔永明段亮伟郑州大学第一附属医院口腔正畸科郑州450052 郑州大学第一附属医院口腔颌面外科郑州450052 郑州大学第一附属医院口腔修复科郑州450052

目的了解颞下颌关节盘不可复性前移位患者自然病程的临床、影像学变化及不同年龄段的差异性。方法选择2016年1月—2023年6月在郑州大学第一附属医院口腔颌面外科就诊的颞下颌关节盘不可复性前移位患者37例(45侧),男性4例,女性33例,平... 详细信息

目的了解颞下颌关节盘不可复性前移位患者自然病程的临床、影像学变化及不同年龄段的差异性。方法选择2016年1月—2023年6月在郑州大学第一附属医院口腔颌面外科就诊的颞下颌关节盘不可复性前移位患者37例(45侧),男性4例,女性33例,平均年龄23.5岁,平均病程14.4个月。收集初诊及复诊时临床及磁共振成像(MRI)资料,测量关节盘的长度和厚度、关节盘前移角度、髁突高度,使用SPSS 25.0进行统计分析,比较临床及影像学的变化。结果 37例(45侧)患者复诊与初诊相比较:3例3侧自愈为可复性盘前移位;48.4%患者自觉张口受限未缓解或加重;58.3%患者张口疼痛无改善;54.5%咀嚼疼痛无改善;33.3%患者面部偏斜呈现加重趋势,仅1例缓解。关节盘前移角度从初诊时61.63°增长至67.81°,关节盘长度从8.20 mm缩短至7.27 mm,髁突高度从23.17 mm降为22.76 mm,以上差异有统计学意义(P0.05)。结论在颞下颌关节盘不可复性前移位自然病程中,部分患者的临床症状不能完全缓解;不同年龄段患者都会出现关节盘前移程度逐渐增大,关节盘长度逐渐缩短,发生折叠变形,髁突出现吸收,继发面部偏斜、下颌后缩等继发畸形。

关键词：颞下颌关节不可复性盘前移位磁共振成像

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硼掺杂介孔炭吸附四环素的效能与机制

环境科学 2024年第2期45卷 885-897页

作者：邹震许路乔伟唐茂森金鹏康西安建筑科技大学环境与市政工程学院西安710055 西安交通大学人居环境与建筑工程学院西安710049

以椰壳和硼酸为原料,通过简单的一步热解法制备出新型硼掺杂椰壳介孔炭材料(B-CSC)用于水中四环素类污染物的高效吸附去除.系统研究了关键制备条件热解温度和硼碳质量比对其吸附性能的影响,使用比表面积及孔径分析仪(BET)、场发射扫描电... 详细信息

以椰壳和硼酸为原料,通过简单的一步热解法制备出新型硼掺杂椰壳介孔炭材料(B-CSC)用于水中四环素类污染物的高效吸附去除.系统研究了关键制备条件热解温度和硼碳质量比对其吸附性能的影响,使用比表面积及孔径分析仪(BET)、场发射扫描电镜(SEM)、X射线光子能谱仪(XPS)、拉曼光谱仪(Raman)以及Zeta电位仪(Zeta)对其微观结构及物化性质进行了表征分析.系统考察了初始pH值、不同金属阳离子以及不同背景水质条件对其吸附效果的影响.结合材料表征与相关分析等对其强化吸附机制进行了深入讨论与分析.结果表明,一步热解能够将硼掺入椰壳炭的表面及晶格,导致其拥有更大的比表面积和孔体积,引入硼的形态主要是H_(3)BO_(3)、B_(2)O_(3)、B和B_(4)C.B-CSC对四环素的吸附量达到297.65 mg·g^(-1),是原始椰壳介孔炭(CSC)的8.9倍.同时,B-CSC对于水环境中常见污染物罗丹明B(RhB)、双酚A(BPA)和亚甲基蓝(MB)的吸附量分别高达372.65、255.24和147.82 mg·g^(-1).B-CSC对四环素的吸附过程是物理化学作用共同主导的,主要涉及液膜扩散、表面吸附、介孔与微孔内扩散和活性位点吸附,H3BO3是其主要吸附位点.吸附强化机制主要是硼掺杂降低了其碳网络的化学惰性,增强了其与四环素分子的π—π相互作用和氢键作用.

关键词：椰壳介孔炭硼掺杂吸附四环素

跨越数字鸿沟:智能手机对老年人劳动参与的影响

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中南民族大学学报（人文社会科学版） 2024年第3期44卷 104-112,185,186页

作者：向运华金巧森武汉大学社会保障研究中心湖北武汉430072

促进老年人劳动参与是应对人口老龄化挑战、实现积极老龄化的重要举措之一,智能手机的普及为提高老年人劳动参与概率与质量带来新的可能。文章基于2016年中国老年社会追踪调查数据,探究了智能手机使用对老年人劳动参与的作用和机制。研... 详细信息

促进老年人劳动参与是应对人口老龄化挑战、实现积极老龄化的重要举措之一,智能手机的普及为提高老年人劳动参与概率与质量带来新的可能。文章基于2016年中国老年社会追踪调查数据,探究了智能手机使用对老年人劳动参与的作用和机制。研究发现:智能手机的使用能够显著提高老年人劳动参与概率,采用稳健性估计与工具变量克服内生性问题后,该结论依然成立;影响机制的检验结果显示,智能手机使用通过扩大和巩固老年人的社会网络,进而促进了其劳动参与。因此,推进智能手机的普及和适老改造工作,提高老年人的智能手机使用能力,巩固和拓展老年人社会网络关系,有助于老年人跨越数字鸿沟,强化智能手机在老年人劳动参与过程中的促进作用。

关键词：智能手机使用劳动参与社会网络积极老龄化