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Wave propagation and energy dissipation in viscoelastic granular media

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Journal of Central South University 2001年第3期13卷 185-188页

作者： SUN Ye-zhi 1, WU Ai-xiang 1, LI Jian-hua 1,2.(1. College of Resources, Environment and Civil Engineering, Central South Unive rsity, Changsha 410083, China 2. the 5th building company in guangdong province, Shaoguan 512.2., China) 1. College of Resources Environment and Civil Engineering Central South University 410083 Changsha China 2. the 5th building company in guangdong province 512026 Shaoguan China

In terms of viscoelasticity, the relevant theory of wave i n granular media is analyzed in this paper. Under the conditions of slight deforma tion of granules, wave equation, complex number expressions of propagation vecto r and attenuation vector, attenuation coefficient expressions of longitudinal wa ve and transverse wave, etc, are analyzed and deduced. the expressions of attenu ation coefficients of viscoelastic longitudinal wave and transverse wave show th a t the attenuation of wave is related to frequency. the higher the frequency is, the more the attenuation is, which is tested by the laboratory experiment. In a ddi tion, the energy dissipation is related to the higher frequency wave that is abs orbed by granular media. the friction amongst granular media also increase the e nergy dissipation. During the flowing situation the expression of transmission f actor of energy shows that the granular density difference is the key factor whi ch leads to the attenuation of vibrating energy. this has been proved by the exp eriment results.

关键词： viscoelastic granular media wave motion energy dissipation flowing situation

Assessing impact of intermittent window opening strategies on pathogen-laden droplet dispersion in a coach bus

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building Simulation 2024年第7期17卷 1183-1200页

作者： Qiqi Luo Xingdong Deng Jian Hang Cuiyun Ou Zhiwen Luo Xiaodan Fan Xia Yang Yifei Zhang Zhongli Gu Xuelin Zhang School of Atmospheric Sciences Sun Yat-sen Universityand Southern Marine Science and Engineering Guangdong LaboratoryZhuhai 519082China Key Laboratory of Urban Meteorology China Meteorological AdministrationBeijing 100089China China Meteorological Administration Xiong'an Atmospheric Boundary Layer Key Laboratory Xiong'anChina Guangzhou Urban Planning&Design Survey Research Institute Guangzhou 510060China Guangzhou Collaborative Innovation Center of Natural Resources Planning and Marine Technology Guangzhou 510060China guangdong Enterprise Key Laboratory for Urban Sensing Monitoring and Early WarningGuangzhou 510060China Welsh Schoolof Architecture Cardiff UniversityUK guangdong province Engineering Laboratory for Air Pollution Control South China Institute of Environmental Sciencesthe Ministry of Ecology and Environment of ChinaNo.7 West Street YuancunGuangzhou 510655China guangdong Fans-tech Agro Co. LtdGuangdong ProvinceChina

Opening windows in coach buses is a practical approach to improving natural ventilation and mitigating infection risk(IR).Due to human behavior and weather conditions,the intermittent window opening strategy(IWOS)is a more common practice than keeping windows constantly *** its prevalence,there are no studies exploring IWOS specifically in *** employed indoor-outdoor coupled CFD simulations to assess the effects of various IWOS on pathogen-laden droplet(PLD)dispersion and IR in a coach bus that occurred a COVID-19 outbreak in Hunan,*** reveal that after ventilating through two skylights for 600–1800 s,opening front and rear windows(FW+RW)or FW with a wind catcher(FW+WCH)for just 40 s can reduce PLD concentration(Cave)to 5%of its initial level and the intake fraction of the infector’s neighbor(IFn)drops by 95%.Upon closing FW+RW or FW+WCH,Cave and IFn take over 580 s to return to the pre-opening ***,intermittent FW opening halves Cave and IFn within 7 min,but leads to rapid increases upon window ***,opening FW+RW and FW+WCH intermittently have pronounced impacts on indoor PLD concentration and are applicable approaches to control respiratory disease transmission in *** to the inhaled viral dose,it is recommended to open windows when driving time is over 12.minutes to reduce infection *** scenarios like epidemiological surveys and risk assessments,where assessing passenger infection risk is vital,some behaviors of opening windows cannot be overlooked and necessitate extra attention.

关键词： infection risk computational fluid dynamics air change rate per hour natural ventilation wind catcher tracer gas dispersion

Discovery of unusual phloroglucinol-triterpenoid adducts from Leptospermum scoparium and Xanthostemon chrysanthus by building blocks-based molecular networking

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Chinese Chemical Letters 2024年第6期35卷 353-357页

作者： Jinyan Zhang Fen Liu Qian Jin Xueyi Li Qiong Zhan Mu Chen Sisi Wang Zhenlong Wu Wencai Ye Lei Wang State Key Laboratory of Bioactive Molecules and Druggability Assessment Jinan UniversityGuangzhou 510632China Center for Bioactive Natural Molecules and Innovative Drugs and Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs ResearchJinan UniversityGuangzhou 510632China College of Pharmacy Jinan UniversityGuangzhou 510632China

the first phloroglucinol-triterpenoid hybrids,myrtphlotritins A-E(1-5),were rapidly recognized and isolated from two species of Myrtaceae by employing the building blocks-based molecular network(BBMN)*** 1-5 featured new carbon skeletons in which phloroglucinol derivatives were coupled with lupane-and dammarane-type triterpenoids through different linkage *** structures and absolute configurations were elucidated by comprehensive analysis of spectroscopic data and quantum chemical *** pathways for compounds 1-5 were proposed on the basis of the coexisting *** by the biogenetic pathways,the biomimetic synthesis of compound 1 was also ***,compounds 2.3,and 5 exhibited potent antiviral activities against herpes simplex virus type-1(HSV-1)infection,and compounds 2.and 5 displayed significant anti-inflammatory activities on RAW2.4.7 cells.

关键词： Phloroglucinol-triterpenoid adduct Myrtaceae building blocks-based molecular network Biomimetic synthesis Antiviral activity Anti-inflammatory activity

Flexible resource allocation optimization model considering global K-means load clustering and renewable-energy consumption

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Clean Energy 2024年第5期8卷 129-143页

作者： Jie Jiao Puyu He Yuhong Zhang Jiyuan Zhang Zhuhan Long Hanjing Liu State Grid Sichuan Electric Power company Economic Research Institute ChengduChina

Vigorously developing flexible resources in power systems will be the key to building a new power system and realizing energy *** investment construction cost and operation cost of various flexible resources are different,and the adjustment ability is different in different ***,the optimization of complementary allocation of various resources needs to take into account the economy and adjustment ability of different *** this paper,the global K-means load clustering model is pro-posed and the 365-day net load is reduced to eight typical daily net loads by ***,a two-level optimization model of flexible resource complementary allocation considering wind power and photovoltaic consumption is *** flexible resources involved include the flexible transformation of thermal power,hydropower,pumped storage,energy storage,and demand *** upper-layer model optimizes the capacity allocation of various flexible resources with the minimum investment and construction cost as the goal and the lower layer optimizes the operating output of various units with the minimum operating cost as the *** results of the example analysis show that the flexible capacity of thermal power units has nothing to do with the abandonment rate of renewable *** the abandonment rate of renewable energy decreases,the optimal capacity of pumped storage,electrochemical energy storage,and hydropower units *** the power-abandonment rate of renewable energy is 5%,the optimal allocation capacity of thermal power flexibility transformation,pumped storage,electrochemical energy storage,hydropower unit,and adjustable load in province A is 5313,17090,5830,72.13,and 42.0 MW,*** the condition that the renewable-energy abandonment rate is 0,5%,and 10%respectively,the configured capacity of pumped storage is 2.000,17090,and 14847 MW,respectively.

关键词： wind power photovoltaic power K-means clustering algorithm flexible resources complementary configuration operation optimization

Down-regulation of microRNA-2.a promotes pancreatic ductal adenocarcinoma initiation and progression by up-regulation of FOXM1 expression

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Genes & Diseases 2024年第5期11卷 456-469页

作者： Lixin Liang Tian Cai Xiaojia Li Jianhong An Sen Yu Yang Zhang Fengjie Guo Fang Wei Jie He Keping Xie Tingting Jiang Center for Pancreatic Cancer Research South China University of Technology School of MedicineGuangzhouGuangdong 510006China Department of Laboratory Medicine The Sixth Affiliated Hospital and Nanhai People’s HospitalSouth China University of Technology School of MedicineFoshanGuangdong 528200China the Second Affiliated Hospital and Guangzhou First People’s Hospital South China University of Technology School of MedicineGuangzhouGuangdong 510006China

Transcriptional factor Forkhead box M1(FOXM1)plays an important role in pancreatic ductal adenocarcinoma(PDAC)development and *** molecular mechanisms underlying its dysregulation remain *** identified and functionally validated the microRNAs(miRNAs)that critically regulate FOXM1 expression in *** expression levels of miRNA-2.a(miR-2.a-3p and-5p)were altered in PDAC cell lines and their effects on FOXM1 signaling and cell proliferation and migration and tumorigenesis were examined in vitro and in vivo using mouse PDAC *** with non-tumor pancreatic tissues,PDAC tissues and cell lines exhibited significantly reduced levels of miR-2.a *** miR-2.a expression and concomitant increase in FOXM1 expression were also observed in acinar-toductal metaplasia and pancreatic intraepithelial neoplasia,the major premalignant lesions of *** expression of miR-2.a reduced the expression of FOXM1 and suppressed cell proliferation and migration in PDAC cells,whereas the inhibitors of miR-2.a did the *** or reduced levels of miR-2.a increased the levels of FOXM1 expression,while increased expression of FOXM1 down-regulated miR-2.a expression,suggesting that miR-2.a and FOXM1 were mutual negative regulators of their expression in PDAC ***,the miR-2.a/FOXM1 signaling axis is important in PDAC initiation and progression and could serve as an interventional or therapeutic target for patients with early or late stages of PDAC.

关键词： FOXM1 Gene expression Gene regulation MicroRNA Pancreatic cancer Targeted therapy

Preliminary research and scheme design of deep underground in situ geo-information detection experiment for Geology in Time

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International Journal of Mining Science and Technology 2024年第1期34卷 1-13页

作者： Heping Xie Ru Zhang Zetian Zhang Yinshuang Ai Jianhui Deng Yun Chen Yong Zhou Mingchuan Li Liqiang Liu Mingzhong Gao Zeqian Yang Weiqiang Ling Heng Gao Qijun Hao Kun Xiao Chendi Lou State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering Sichuan UniversityChengdu 610065China College of Water Resource&Hydropower Sichuan UniversityChengdu 610065China guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green EnergyShenzhen UniversityShenzhen 518060China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China Yalong River Hydropower Development company Limited Chengdu 610051China

the deep earth,deep sea,and deep space are the main parts of the national“three deep”strategy,which is in the forefront of the strategic deployment clearly defined in China’s 14th Five-Year Plan(2.2.-2.2.)and the Long-Range Objectives through the Year *** is important to reveal the evolutionary process and mechanism of deep tectonics to understand the earth’s past,present and *** academic con-notation of Geology in Time has been given for the first time,which refers to the multi-field evolution response process of geological bodies at different time and spatial scales caused by geological processes inside and outside the *** on the deep in situ detection space and the unique geological envi-ronment of China Jinping Underground Laboratory,the scientific issue of the correlation mechanism and law between deep internal time-varying and shallow geological response is given *** research and frontier exploration on deep underground in situ geo-information detection experiments for Geology in Time are designed to be carried out,which will have the potential to explore the driving force of Geology in Time,reveal essential laws of deep earth science,and explore innovative technologies in deep underground engineering.

关键词： Deep underground Geology in Time China Jinping Underground Laboratory In situ detection

Tocilizumab promotes corneal allograft survival in rats by modulating Treg-th17 balance

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International Journal of Ophthalmology(English edition) 2019年第12期12卷 1823-1831页

作者： Xiao-Song Wu Xiao-Li Lu Jing Wu Ming Ma Jian Yu Zhen-Yu Zhang Dpartment of Ophthalmology Nanfang HospitalSouthern Medical UniversityGuangzhou 510515Guangdong ProvinceChina Department of Huiqiao building Nanfang HospitalSouthern Medical UniversityGuangzhou 510515Guangdong ProvinceChina guangdong Women And Children Hospital Guangzhou 511400Guangdong ProvinceChina

AIM: To examine the therapeutic effects of tocilizumab on experimental corneal transplantation and its effect on Treg/th17 balance. MEthODS: Allograft corneal graft was performed between host Sprague Dawley and Wistar donor *** rats were randomly divided into four groups: normal,autograft, allograft, and allograft treated with ***-Meier was performed to draw the survival *** protein levels of interleukin-17A(IL-17A), vascular endothelial growth factor(VEGF), and forkhead box protein3(Foxp3) were measured by *** mRNA levels of IL-17A, VEGF, retinoid-related orphan receptor gammat(RORγt), interleukin-6(IL-6) and Foxp3 were detected by reverse transcription real-time polymerase chain reaction(RT-PCR). the Treg and th17 cells were investigated by flow cytometry. RESULTS: the survival time of tocilizumab group was(2.±1.2. d) longer than that of allograft group(10±0.55 d).Moreover, immunohistochemical examination revealed that IL-17A and VEGF protein levels in the allograft group were significantly higher than that of tocilizumab group(Pthe allograft group was significantly lower than that of the tocilizumab treated group(Pthat the number of th17 cellsin allograft group was significantly higher than that in tocilizumab group(Pthe number of Tregs was significantly lower than in tocilizumab group(Pthan other groups(Pthese findings suggest that tocilizumab may promote corneal allograft survival, possibly by modulating Treg-th17 balance.

关键词： tocilizumab corneal transplantation th17/Treg rats

Protective effect of paeonol on beta-amyloid 2.-35- induced toxicity in PC12.cells

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Neural Regeneration Research 2008年第8期3卷 863-866页

作者： Daohua Xu Chenhui Zhou Bilian Xu Shiying Luo Department of Pharmacology Guangdong Medical College Zhanjiang 524023 Guangdeng Province China School of Nursing Guangdong Medical College Zhanjiang 524023 Guangdong Province China

BACKGROUND：Paeonol is a primary phenolic component of the Chinese medicinal herb Cortex moutan. Recent studies have shown that paeonol has anti-inflammatory, analgesic, and antioxidative effects as well as a significant cardioprotective effect against myocardial ischemia. OBJECTIVE： To investigate the protective effect of paeonol on β-amyloid 2.-35-induced toxicity in PC12.cells and analyze its mechanism of action. DESIGN, TIME AND SETTING： A controlled repeated-measures cell-based study was performed in the Department of Pharmacology of guangdong Medical College between September 2.06 and December 2.07. MATERIALS： Paeonol was supplied by Xuancheng Baicao Plant Industry and Trade company, China. PC12.cells were a kind gift from Dr. Haitao Zhang at guangdong Medical College. β-amyloid 2.-35 was purchased from Sigma company, USA. Lactate dehydrogenase （LDH） and malondialdehyde （MDA） kits were purchased from Nanjing Jiancheng Bioengineering Research Institute, China. MEthODS： PC12.cells were maintained in Dulbecco＇s modified eagle＇s medium （DMEM） supplemented with 100 mL/L heat-inactivated horse serum and 50 mL/L fetal bovine serum at 37 ℃ and cultured in an incubator with 5% CO2. the medium was renewed every other day. Batches of cells were assigned into three groups. （1） Paeonol group： cells were preincubated with different concentrations of paeonol （12. 2. or 50 μmol/L） for one hour and β-amyloid 2.-35 was added to the medium; （2. control group： cells were cultured in DMEM supplemented with 100 mL/L heat-inactivated horse serum and 50 mL/L fetal bovine serum; and （3） β-amyloid 2.-35 group： β-amyloid 2.-35 was added to the medium. MAIN OUTCOME MEASURES： When PC12.cells in each group were cultured for 2. hours, the cell viability was determined using the MTT reduction assay, LDH release into the culture media was measured by 2.4-dinitrophenylhydrazine chromatometry and MDA content was measured using a thiobarbituric acid assay. RESULTS： When PC12.cells were treated wi

关键词： paeonol PC12.cells Alzheimer's disease β-amyloid

Long-term observation on safety and visual quality of implantable collamer lens V4c implantation for myopia correction:a 5-year follow-up

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International Journal of Ophthalmology(English edition) 2023年第7期16卷 1123-1129页

作者： Xiao Chen Li Li Jing Rao Yue-Xi Chen Yang Gao Rui-Xue Huang Qi-Zhi Zhou Aier Eye Hospital Jinan UniversityGuangzhou 510071Guangdong ProvinceChina Chongqing Aier and Vision Care Hospital Chongqing 400000China Aier Eye Hospital Group company Limited Changsha 410000Hunan ProvinceChina Jinan University Guangzhou 510000Guangdong ProvinceChina

AIM:To elucidate the safety and visual quality of implantable collamer lens with central hole(ICL V4c)implantation for correcting moderate and high myopia for at least ***:this retrospective study was conducted on 58 patients(114 eyes)who were followed up for at least 5y after ICL V4c *** observation was done before and on 1d,1mo,1 and 5y or more after the surgical *** visual acuity,subjective refraction,intraocular pressure,vault,axial length,central hole position,pupil diameter,visual quality,and adverse events were *** visual quality includes aberration,the modulation transfer function cutoff frequency(MTF cutoff),objective scattering index(OSI),Stroller's ratio(SR),and visual quality ***:the average follow-up period was 69.2.±3.80mo(range 60–82.o)and the preoperative spherical equivalent(SE)was-8.66±1.97 *** 5y after operation,the safety index was 1.01±0.02.and the efficacy index was 0.99±0.42.and SE was-0.65±0.63 *** 59.6%of the eyes achieved an uncorrected distance visual acuity of 2./2.,76.3%of the eyes had SE within±1.0 D at the last *** axial length increased by 0.2.±0.71 mm 5y after the surgery(t=-3.843,Pthe mean vault at the last follow-up was 510.59±2.5.61μ*** central hole was on the temporal side in 80 eyes(84.2.).the visual quality questionnaire showed that 98.2.patients were satisfied with the surgical *** events occurred in 4 eyes(3.5%),including the posttraumatic toric ICL rotation(2.eyes),iris incarceration(1 eye),and posttraumatic ICL displacement(1 eye)at the last ***:Long-term ICL V4c implantation is safe,effective,and stable for correcting moderate and to high myopia,and the visual quality with patients is excellent and satisfactory,but the progression of axial length still needs attention after surgery.

关键词： implantable collamer lens with central hole myopia correction refractive surgery visual quality