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Property(R)for Upper Triangular Operator Matrices

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Acta Mathematica Sinica,English Series 2023年第3期39卷 523-532页

作者： Li Li yang xiao hong CAO School of Mathematics and Statistics Shaanxi Normal UniversityXi’an 710119P.R.China

Property(R)holds for an operator when the complement in the approximate point spectrum of the Browder essential approximate point spectrum coincides with the isolated points of the spectrum which are eigenvalues of finite multiplicity.Let A∈B(H)and B∈B(K),where H and K are complex infinite dimensional separable Hilbert spaces.We denote by M_(C)the operator acting on H⊕K of the form M_(C)=(AC0B).In this paper,we give a sufficient and necessary condition for M_(C)∈(R)for all C∈B(K,H).

关键词： property(R) upper triangular operator matrix spectrum

More Cycles of Intravenous Chemotherapy are Associated with Reduced Growth in Children with Retinoblastoma

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Journal of Nutritional Oncology 2021年第3期6卷 126-133页

作者： Yu Qiong yang Liang Yu Yin Xin Lin Bing Hao xiao Yue Guan hong Xia Xu hong Feng Yuan Department of Ophthalmology Daping HospitalArmy Medical University(Third Military Medical University)Chongqing 400042China Department of Clinical Nutrition Daping HospitalArmy Medical University(Third Military Medical University)Chongqing 400042China Institute of Hepatopancreatobiliary Surgery Southwest HospitalArmy Medical University(Third Military Medical University)Chongqing 400038China

Background Chemotherapy can have a negative impact on the growth of children with different cancers.However,few studies have examined whether intravenous chemotherapy(IVC)affects the growth of children with retinoblastoma(RB).The present study evaluated the height differences(actual height compared to the age standardized value)and survival of pediatric RB patients treated with IVC.Methods This was an observational cohort study.A total of 87 pediatric RB patients were included.The study population was stratified into two groups based on the number of chemotherapy cycles administered(≤4 versus>4).The height at baseline(before IVC),height after IVC and overall survival were compared between the two groups.Results Before IVC,no height differences were observed between the two groups(P=0.585).After IVC,all of the patients had a reduced height compared to the age standardized height(P=0.035).Patients who underwent more cycles of chemotherapy had a greater height difference compared to those who received fewer cycles(P=0.008).For those who had reduced height,the difference was positively associated with the number of chemotherapy cycles(r=0.279,P=0.043).Among the patients who exhibited a greater height difference,those who underwent more than four cycles of chemotherapy had a decreased overall survival(P=0.042).Conclusions Pediatric RB patients who underwent more cycles of chemotherapy were more likely to have a reduced height.Further studies are needed to determine the optimal treatment strategy to prevent the reduced growth while maintaining the benefits of chemotherapy.

关键词： Retinoblastoma Intravenous chemotherapy Height Survival

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Two-person device-free localization system based on ZigBee and transformer

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High Technology Letters 2024年第1期30卷 61-67页

作者：刘天蒙 yang Hai xiao WU hong School of Electronic Information and Optical Engineering Nankai UniversityTianjin 300350P.R.China Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology Nankai UniversityTianjin 300350P.R.China Engineering Research Center of Thin Film Optoelectronics Technology Nankai UniversityTianjin 300350P.R.China

Most studies on device-free localization currently focus on single-person scenarios.This paper proposes a novel method for device-free localization that utilizes ZigBee received signal strength indication(RSSI)and a Transformer network structure.The method aims to address the limited research and low accuracy of two-person device-free localization.This paper first describes the construction of the sensor network used for collecting ZigBee RSSI.It then examines the format and features of ZigBee data packages.The algorithm design of this paper is then introduced.The box plot method is used to identify abnormal data points,and a neural network is used to establish the mapping model between ZigBee RSSI matrix and localization coordinates.This neural network includes a Transformer encoder layer as the encoder and a fully connected network as the decoder.The proposed method's classification accuracy was experimentally tested in an online test stage,resulting in an accuracy rate of 98.79%.In conclusion,the proposed two-person localization system is novel and has demonstrated high accuracy.

关键词： device-free localization deep learning ZigBee

Nurses’ knowledge, perceptions, and behaviors regarding antineoplastic drugs:the mediating role of protective knowledge

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Frontiers of Nursing 2022年第2期9卷 155-163页

作者： Ning Liu hong Lu xiao-Qing Yi yang yang xiao-hong Huang Nursing Faculty Zhuhai Campus of Zunyi Medical UniversityZhuhaiGuangdong 509041China Department of Nursing Chinese Academy of Medical Sciences Cancer Hospital Shenzhen HospitalShenzhenGuangdong 518116China Department of Nursing Baoan District People’s Hospital of ShenzhenShenzhenGuangdong 518101China Department of Nursing Longgang District Central Hospital of ShenzhenShenzhenGuangdong 518116China

Objective:To explore the relationships between Chinese nurses’knowledge,perceptions,and attitudes and their behavior and actual implementation of safety measures when handling antineoplastic drugs(ADs)in their daily work.Methods:This was a multisite study conducted in 8 public hospitals in China.A self-administered questionnaire was sent to par ticipants querying the degree of contact with ADs.The hypothesized relations were explored using structural equation modelling via the bootstrap method.Mediation analysis was applied to explore the mediating role of protective knowledge regarding AD exposure on the associations among protective training,using warning labels,and using protective masks.Results:A total of 305 nurses were enrolled.The average age of all par ticipants was 30.2(standard deviation[SD]:6.2)years.Nurses who had received protective training for AD exposure were more likely to use labels for ADs after age,body mass index(BMI),length of service,marital status,education,and department were controlled as covariates.The bias-corrected bootstrap of 95%confidence interval(CI)indicated that protective knowledge significantly mediated(23.4%)the association between protective training and using labels(indirect effect=0.202,95%CI:0.009,0.495);the proportion of mediation was 23.4%.Protective knowledge significantly mediated the association between protective training and using protective masks(indirect effect=0.157,95%CI:0.048,0.325);the propor tion of mediation was 27.2%.Conclusions:The findings of this study have provided baseline information on the current state of Chinese nurses’perceptions,knowledge,and preventive behaviors toward ADs as the crisis is happening.Training is also recommended to improve nurses’perceptions of the risks associated with ADs.

关键词： antineoplastic drugs Chinese nurses developed city mediation occupational exposure

The roles of microRNAs in regulating root formation and growth in plants

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Journal of Integrative Agriculture 2022年第4期21卷 901-916页

作者： YAN xiao-xiao LIU Xiang-yang CUI hong ZHAO Ming-qin College of Tobacco Science Henan Agricultural University/National Tobacco Cultivation and Physiology and Biochemistry Research Center/Key Laboratory for Tobacco Cultivation of Tobacco IndustryZhengzhou 450002P.R.China

MicroRNAs(miRNAs) are small(ca. 20-24 nucleotides) non-coding RNAs that have recently been recognized as key post-transcriptional modulators of gene expression;and they are involved in many biological processes in plants, such as root growth and development. The miRNAs regulate root elongation, lateral root(LR) formation and adventitious root(AR) development in response to hormone signaling, nutrient uptake and biotic/abiotic stress. This review provides multiple perspectives on the involvement of miRNAs in regulating root growth and development in plants. We also discuss several crucial mechanisms of miRNAs, their relationships with transcription factors and the target gene-mediated hormone signaling interactions in the regulation of root growth and development.

关键词： microRNAs adventitious root lateral root primary root

The integration of dinitropyrazole and 1,3,4-oxadiazole:A novel hybrid heterocyclic skeleton for balancing energy and stability

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Defence Technology（防务技术） 2023年第6期24卷 122-128页

作者： xiao-xiao Zheng Ting-ou Yan Lei Qian hong-wei yang Guang-bin Cheng School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing210094China

In this study,a new energetic hybrid skeleton was constructed through the integration of nitropyrazole and 1,3,4-oxadiazole skeletons in a molecule.Furthermore,the energetic precursor(2),the azo-bridged compound(3),the neutral nitramine(4)and the corresponding energetic salts(5-7)were synthesized.Their physicochemical and energetic properties we re experimentally and theo retically evaluated.Among the developed compounds,the azo-bridged compound(3)and dihydroxylammoinium(6)display high detonation performances(3,D_(v)=8904 m/s,P=34.47 GPa;6,D_(v)=9025 m/s,P=34.66 GPa),moderate sensitivities(3,IS=16 J,FS=120 N;6,IS=20 J,FS=312 N)and good densities(3,1.87 g/cm^(3);6,1.81 g/cm^(3)),which indicates that they have the potential to replace the traditional high-energy explosive RDX.The results show that the integration of different energetic skeletons can achieve a good balance between energy and sensitivity.

关键词： Heterocycle Azo-bridged Hybrid skeletons Energetic materials

Hydrogen peroxide is a risk factor for occupational chemical poisoning

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Chinese Medical Journal 2021年第7期134卷 881-882页

作者： xiao-Yan yang hong-Ying Liu Departm ent of Occupational Health Ankang Center for Disease Control and PreventionAnkangShaanxi 725000China Department of Occupational Health Baoji Center for Disease Control and PreventionBaojiShaanxi 721000China

To the Editor:Hydrogen peroxide is a strong oxidant,which is commonly used as a disinfectant mainly in medical and chemical workplaces.Hydrogen peroxide poisoning causes brain infarction,and ingestion of hydrogen peroxide injures the upper gastrointestinal tract.[1]Besides,food poisoning is often caused due to hydrogen peroxide.A case has been reported in China that cerebral embolism was caused by oral hydrogen peroxide poisoning.[2]The first two cases of hydrogen peroxide poisoning caused by sterilization and disinfection in China are illustrated in this article.

关键词： hydrogen peroxide chemical

Effect of annealing on properties of Al/steel composite plates prepared by surface oxidation treatment before cold roll bonding

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Journal of Iron and Steel Research(International) 2023年第4期30卷 749-759页

作者： Lun Fu Yu-fei Zhu Bin yang Chao Yu hong xiao National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao 066004HebeiChina

Al/steel composite plate has a wide application prospect,but great differences in properties between Al and steel are observed.It is difficult to obtain high bonding strength by the traditional cold roll bonding process.Al/steel composite plate was thus prepared by cold roll bonding at a reduction rate of 60%after oxidation treatment on the surface to be composited on the steel side.The heat treatment of holding at 400℃ for 1 h and cooling with the furnace was then adopted.The bonding strength,microstructure,and properties of the Al/steel composite plate before and after annealing were analysed and compared through shear test,bending test,tensile test,and micro-characterization.Results show that the shear strengths of the interface before and after annealing are 100 and 80 MPa,respectively.Although the shear strength of the annealed Al/steel composite plate decreases,the bending and overall tensile properties of the composite plate are improved,showing better mechanical properties.

关键词： Al/steel composite plate Oxidation treatment Annealing treatment Shear strength Cold roll bonding

Enhance liquid nitrogen fracturing performance on hot dry rock by cyclic injection

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Petroleum Science 2023年第2期20卷 951-972页

作者： Chun-yang hong Rui-Yue yang Zhong-Wei Huang xiao-Ying Zhuang Hai-Tao Wen xiao-Li Hu State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China Chair of Computational Science and Simulation Technology Faculty of Mathematics and PhysicsLeibniz Universität HannoverHannover30167Germany

Producing complex fracture networks in a safe way plays a critical role in the hot dry rock (HDR) geothermal energy exploitation. However, conventional hydraulic fracturing (HF) generally produces high breakdown pressure and results only in single main fracture morphology. Furthermore, HF has also other problems such as the increased risk of seismic events and consuption of large amount of water. In this work, a new stimulation method based on cyclic soft stimulation (CSS) and liquid nitrogen (LN2) fracturing, known as cyclic LN2 fracturing is explored, which we believe has the potential to solve the above issues related to HF. The fracturing performances including breakdown pressure and fracture morphology on granites under true-triaxial stresses are investigated and compared with cyclic water fracturing. Cryo-scanning electron microscopy (Cryo-SEM) tests and X-ray computed tomography (CT) scanning tests were used for quantitative characterization of fracture parameters and to evaluate the cyclic LN2 fracturing performances. The results demonstrate that the cyclic LN2 fracturing results in reduced breakdown pressure, with between 21% and 67% lower pressure compared with using cyclic water fracturing. Cyclic LN2 fracturing tends to produce more complex and branched fractures, whereas cyclic water fracturing usually produces a single main fracture under a low number of cycles and pressure levels. Thermally-induced fractures mostly occur around the interfaces of different particles. This study shows the potential benefits of cyclic LN2 fracturing on HDR. It is expected to provide theoretical guidance for the cyclic LN2 fracturing application in HDR reservoirs.

关键词： Hot dry rock Liquid nitrogen fracturing Cyclic injection Thermal stress Fatigue damage