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东北地区黑土地保护利用与乡村振兴的融合机理及互馈理路研究——基于典型村庄的过程追踪调查

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自然资源学报 2024年第5期39卷 1193-1207页

作者：李政宏吕晓徐畅牛善栋王亚男东北大学文法学院沈阳110169

化解东北地区乡村贫困与黑土地退化高度重叠问题,需探索统筹实施黑土地保护利用与乡村振兴的系统策略,发现其背后的因果关系。在解析东北地区黑土地保护利用与乡村振兴二者间融合机理的基础上,运用过程追踪法对典型案例村庄开展调查,厘... 详细信息

化解东北地区乡村贫困与黑土地退化高度重叠问题,需探索统筹实施黑土地保护利用与乡村振兴的系统策略,发现其背后的因果关系。在解析东北地区黑土地保护利用与乡村振兴二者间融合机理的基础上,运用过程追踪法对典型案例村庄开展调查,厘清二者间的互馈理路,明晰内在因果传导路径。研究发现:(1)二者在目标上高度统一、内涵上高度融合、利益上相互协调、措施上相互补充;(2)从驱动机制、链接机制、助推机制解析二者间的互馈理路,要求推动要素层整合优化、政策层中介链接、资源层转化提升;(3)要素驱动型、政策主导型、资源赋能型三类村庄发展历程具有差异化的因果传导路径。需从保护黑土资源本底、加快生产要素驱动、健全政策统筹机制、采取差异化发展路径四个方面支撑二者统筹发展。

关键词：黑土地保护利用乡村振兴融合机理互馈理路过程追踪

降低新生儿重症监护室极低出生体重早产儿抗生素使用时间的质量改进研究

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中国当代儿科杂志 2024年第7期26卷 736-742页

作者：全美盈冯淑菊张玉王晨张乐嘉李正红中国医学科学院北京协和医院儿科/疑难重症及罕见病国家重点实验室北京100730

目的应用质量改进的方法,制定降低新生儿重症监护室极低出生体重(very low birth weight,VLBW)早产儿抗生素使用时间的有效措施,以减少抗生素的使用。方法以住院VLBW早产儿为研究对象,以2020年11月—2021年6月VLBW早产儿住院期间抗生素... 详细信息

目的应用质量改进的方法,制定降低新生儿重症监护室极低出生体重(very low birth weight,VLBW)早产儿抗生素使用时间的有效措施,以减少抗生素的使用。方法以住院VLBW早产儿为研究对象,以2020年11月—2021年6月VLBW早产儿住院期间抗生素使用时间占住院时间百分比作为基线值,以降低抗生素使用时间占住院时间百分比为具体质量改进目标。应用帕累托图分析影响早产儿抗生素使用时间的因素。根据抗生素使用的各个环节构建关键驱动图,确定质量改进的关键环节和具体的干预措施。通过运行图监测VLBW早产儿抗生素使用时间占住院时间百分比的变化直至达到质量改进目标。结果2020年11月—2021年6月VLBW早产儿抗生素使用时间占住院时间百分比在质量改进前为49%(基线值),设定质量改进目标为12个月内将该百分比降低10%。帕累托图分析显示影响早产儿的抗生素使用时间的主要因素为:抗生素使用不规范;无感染证据时未及时停用抗生素;中心静脉置管留置时间长;袋鼠式护理应用不足;肠内营养进程延迟。质量改进采取的干预措施包括:(1)制定败血症评估管理规范;(2)对医护人员进行关于早产儿抗生素合理使用的宣教;(3)查房时监督抗生素使用规范的执行性;(4)无明确感染表现且血培养阴性者,抗生素使用36 h后停止使用;(5)减少中心静脉置管及肠外营养时间,降低早产儿感染风险。控制图显示,随着干预措施的实施,VLBW早产儿抗生素使用时间占住院时间百分比由49%降低至32%,具有统计学意义。结论应用基于统计原理、过程控制的质量改进工具及质量改进措施后,VLBW早产儿的抗生素使用时间可得到显著降低。

关键词：质量改进抗生素管理新生儿重症监护室极低出生体重儿早产儿

Performance analysis of a rate adaptive multi-band ultra-wideband system based on quadrature fractal modulation scheme

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通信学报 2005年第10期26卷 34-40页

作者： li Yu-hong ZHOU zheng Wireless Network Lab Beijing University of Posts and Telecommunications Beijing 100876 China

A rate adaptive multi-band ultra-wideband (UWB) system based on the quadrature fractal modulation (QFM) scheme was *** the use of homogeneous signals as modulating waveforms in UWB system,the signal within each 528MHz sub-band was divided into 8 different frequency bandwidths using wavelets transform and these data sequences to be transmitted were embedded into homogeneous *** is found that the use of homogeneous signals in such UWB system is quite feasible,leadings to a novel multi-rate diversity *** each 528MHz sub-band,the UWB-QFM system can provide much higher data rates than that of the UWB orthogonal frequency division multiplexing (OFDM) *** results also show that the bit error rate (BER) performance of the UWB-QFM system achieves a greatly improvement over existing UWB-OFDM *** to the fractal properties of the homogeneous signals,these data sequences to be transmitted can be recovered using arbitrarily short receiver signal.

关键词：多频率传输积分调制微波传输直角频率分割多路技术

Combustion Synthesis of h-BN-SiC Ceramic Composites

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Chinese Journal of Aeronautics 2006年第B12期19卷 51-54页

作者： li hong-bo zheng Yong-ting ZHOU li-juan HANJie-cai Center for Composite Materials Harbin Institute of Technology Harbin 150001 China

The feasibility was demonstrated to fabricate h-BN-SiC ceramics through combustion synthesis of the mixture of boron carbide and silicon powders under 100 MPa nitrogen pressure. The mass fraction of BN and SiC in the combustion products were found to be 72 % and 28 % respectively. The thermodynamics of the synthesis reaction and the adiabatic combustion temperature were calculated on the theoretical ground. The bending strengths of the ceramics were measured to be 65.2 MPa at room temperature and 55 MPa at 1350℃ The phase composition and microstructure of the combustion products were identified by X-ray diffraction （XRD） and scanning electron microscopy （SEM）.

关键词： combustion synthesis high-temperature ceramic h-BN-SiC

Synthesis and Herbicidal Activity of Novel 5-Substituted Benzenesulfonylureas

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Chemical Research in Chinese Universities 2007年第6期23卷 674-678页

作者： WANG Mei-yi MU Xiao-li GUO Wan-cheng li Yong-hong li zheng-ming State Key Laboratory of Elemento-Organic Chemistry Research Institute of Elemento-Organic Chemistry Nankai University Tianfin 300071 P. R. China

Sulfonylurea herbicides have been widely used because of their low application rates, good crop sdeetivities and low mammalian toxicities. However, some sulfonylureas might persist unfavourably in the environment with residual problems. In order to look for ecologically safer and environmentally benign sulfonylureas, and on keeping the pyrimidine ring being monosubstitated, 15 novd C5-monosubstituted benzenesulfonylurea compounds were synthesized. The structures of all the compounds synthesized were confirmed by demental analysis and ^1H NMR. Preliminary herbicidal activities of these new sulfonylurea compounds were determined by ALS screening （ in vitro） and pot bioassay experiments（ in vivo）. The herbicidal results show that some novel sulfonylureas are comparable to commercial Foramsulfuron and Monosulfuron.

关键词： Sulfonylurea 5-Substituted phenyl ring Herbicidal activity

Design,Synthesis and Biological Activity of Ethyl 2-(N-Substituted-arylsulfonamido)-2-oxoacetate

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Chemical Research in Chinese Universities 2008年第4期24卷 477-480页

作者： WANG Bao-lei WU Jing HE Feng-qi li Yong-hong li zheng-ming Elemento-Organic Chemistry Institute State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 P. R. China

Thirteen new ethyl 2-（N-substituted-arylsulfonamido）-2-oxoacetates（3a-3m）, based on the structure of Ketol-acid reductoisomerase（KARI） inhibitor IpOHA, were designed and synthesized. Their structures were established on the basis of ^1H NMR, IR, MS, and elemental analyses. The bioassay result reveals that the structural changes from hydroxyl group on the N atom of IpOHA to arylsulfonyl groups does not enhance the inhibitory activity of the compounds to KARI in vitro. Compounds 3c, 3h, 3k, and 3m are more effective than IpOHA against the monocotyledonous bamygrass at 100 ug/mL in herbicidal tests.

关键词： Arylsulfonamide Oxoacetate Synthesis Biological activity

Onset of Coronary Heart Disease is Associated with HCMV Infection and Increased CD14^+CD16^+Monocytes in a Population of Weifang,China

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Biomedical and Environmental Sciences 2020年第8期33卷 573-582页

作者： li hong zheng WANG Qin ZHANG Yi Yuan WANG Jin Dong WU hong Juan ZHANG Mo Gen li Ji Chen liU Zhi Jun Department of Medical Microbiology Weifang Medical UniversityWeifang 261053ShandongChina National Institute for Viral Diseases Control and Prevention China Center for Disease Control and PreventionBeijing 102206China School of Clinical Medicine Weifang Medical UniversityWeifang 261053ShandongChina Morphological Laboratory Weifang Medical UniversityWeifang 261053ShandongChina

Objective To investigate the relationship between human cytomegalovirus(HCMV)infection and peripheral blood CD14+CD16+monocytes in the pathogenesis of coronary heart disease(CHD),and to elucidate the mechanism of pathogenesis in CHD by analyzing the correlation between infection,inflammation,and CHD,to provide a basis for the prevention,evaluation,and treatment of the *** In total,192 patients with CHD were divided into three groups:latent CHD,angina pectoris,and myocardial ***-IgM and-IgG antibodies were assessed using EliSA;CD14+CD16+monocytes were counted using a five-type automated hematology analyzer;mononuclear cells were assessed using fluorescence-activated cell sorting;and an automatic biochemical analyzer was used to measure the levels of triglyceride,cholesterol,high-and low-density lipoprotein cholesterols,lipoprotein,hs-CRp and *** The positive rates of HCMV-IgM and-IgG were significantly higher in the CHD groups than in the control *** infection affects lipid metabolism to promote immune and inflammatory *** HCMV infection has a specific correlation with the occurrence and development of *** expression of CD14+CD16+mononuclear cells in the CHD group was increased accordingly and correlated with acute HCMV ***,HCMV antibody as well as peripheral blood CD14+CD16+mononuclear cells can be used to monitor the occurrence and development of CHD.

关键词： Human cytomegalovirus Coronary heart disease Antibody CD14+CD16+monocytes Weifang

Ballistic performance of spherical fragments penetrating PCrNi3MoV target plates

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Defence Technology（防务技术） 2024年第3期33卷 295-307页

作者： Dou hong Wenbin li Yu zheng Yiming li Ning Jiang Kebin Zhang Ministerial Key Laboratory of ZNDY Nanjing University of Science and TechnologyNanjingChina

PCrNi3MoV steel is a medium-carbon,low-alloy quenched and tempered steel that finds its applications in military gun barrels due to the high wear resistance and ablation *** study the penetration and failure modes of PCrNi3MoV plates impacted by tungsten spheres,tungsten spheres of various diameters(5 mm,8 mm,and 10 mm)were used to impact PCrNi3MoV steel plates with thicknesses of 6 mm,9 mm,and 14 *** penetration performance of the spheres was analyzed for different velocities,and the ultimate penetration velocity of the plate was *** was found that the primary failure modes of the PCrNi3MoV plate were compression pitting failure and shear *** the dimensional analysis method,a relationship between the bulge height of the steel plate and the fragment velocity,an equation for the ultimate penetration velocity,and a relationship between the target penetration energy and the fragment velocity were ***,a projectile-target action index was proposed to describe the process of tungsten spheres with different velocities impacting target *** results suggested that under the same thickness of the target plate,a larger-diameter fragment required more kinetic energy to obtain the same ultimate penetration effect as a smaller-diameter *** equations obtained through dimensional analysis predicted values that agreed well with experimental values,indicating that these equations can be applied to engineering applications.

关键词： Impact damage Ultimate penetration velocity Bulge height Target penetration energy Failure modes

The Multiple Roles of Autophagy in Neural Function and Diseases

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Neuroscience Bulletin 2024年第3期40卷 363-382页

作者： Yan-Yan li zheng-hong Qin Rui Sheng Department of Pharmacology and Laboratory of Aging and Nervous Diseases Jiangsu Key laboratory of Neuropsychiatric DiseasesCollege of Pharmaceutical Sciences of Soochow UniversitySuzhou 215123China

Autophagy involves the sequestration and delivery of cytoplasmic materials to lysosomes,where proteins,lipids,and organelles are degraded and *** to the way the cytoplasmic components are engulfed,autophagy can be divided into macroautophagy,microautophagy,and chaperone-mediated ***,many studies have found that autophagy plays an important role in neurological diseases,including Alzheimer's disease,Parkinson's disease,Huntington's disease,neuronal excitotoxicity,and cerebral *** maintains cell homeostasis in the nervous system via degradation of misfolded proteins,elimination of damaged organelles,and regulation of apoptosis and ***-mTOR,Beclin 1,TP53,endoplasmic reticulum stress,and other signal pathways are involved in the regulation of autophagy and can be used as potential therapeutic targets for neurological ***,we discuss the role,functions,and signal pathways of autophagy in neurological diseases,which will shed light on the pathogenic mechanisms of neurological diseases and suggest novel targets for therapies.

关键词： Autophagy Neurodegenerative diseases Cerebral ischemia AMPK mTOR Beclin 1 TP53 Endoplasmic reticulum stress