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A standing wave tube method for measuring acoustic and vibration characteristics of underwater acoustic materials

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Chinese Journal of Acoustics 2024年第3期43卷 348-362页

作者： LI Shui YI Yan mo Xiping liu Yongping HE Tao TONG Haoyang Hangzhou Applied Acoustics Research Institute Hangzhou311400 Institute of Acoustics Chinese Academy of SciencesBeijing100190

A measurement method based on standing wave tube is proposed to get the acoustic and vibration characteristic parameters of underwater acoustic materials under hydrostatic pressure.A low-frequency emission transducer with pneumatic compensation is designed as the sound source for standing wave *** a water column,the planar piston vibration of the transducer is coupled to the sample under the water *** accelerometer is installed on the backing of the tested sample to measure the vibration velocity of the sample ***,a pair of hydrophones embedded in the tube wall is used to measure the sound pressure of the water *** on the measured data,the vibration velocity and sound pressure of the sample surface of incidence are *** vibration velocity transfer coefficient(decoupling coefficient)between the front and back surfaces of the sample,the input impedance,and the sound pressure reflection coefficient of the sample are then calculated.A low-frequency standing wave tube test system is constructed with a tube size of 300 mm inner diameter,600 mm outer diameter,and 3 m in height,with a frequency range of 100 Hz to 1000 *** experimental studies are conducted using water layer samples and multi-layer perforated rubber *** results show good agreement with the simulation data,thus validating the effectiveness of the measurement method.

关键词： surface method wave

Oligomeric procyanidins combined with Parabacteroides distasonis ameliorate high-fat diet-induced atherosclerosis by regulating lipid metabolism,inflammation reaction and bile acid metabolism in ApoE^(-/-)mice

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Food Science and Human Wellness 2024年第5期13卷 2847-2856页

作者： Mingjuan Xu Cheng Lü Yiqing Hu mo Zhang Jinxin Shen Chunyi liu Qun Lu Rui liu College of Food Science and Technology Huazhong Agricultural UniversityWuhan 430070China Wuhan Engineering Research Center of Bee Products on Quality and Safety Control Wuhan 430070China Institute for Environment and Safety Wuhan Academy of Agricultural SciencesWuhan 430070China Key Laboratory of Environment Correlative Dietology(Huazhong Agricultural University) Ministry of EducationWuhan 430070China Key Laboratory of Urban Agriculture in Central China Ministry of Agriculture and Rural AffairsWuhan 430070China

Atherosclerosis(AS)is the main pathological basis of cardiovascular ***,the prevention and treatment strategies of AS have attracted great research *** a potential probiotic,Pararabacteroides distasonis has a positive regulatory effect on lipid metabolism and bile acids(BAs)*** procyanidins have been confirmed to be conducive to the prevention and treatment of AS,whose antiatherosclerotic effect may be associated with the promotion of gut ***,it remains unclear whether and how oligomeric procyanidins and *** combined(PPC)treatment can effectively alleviate high-fat diet(HFD)-induced *** this study,PPC treatment was found to significantly decrease atherosclerotic lesion,as well as alleviate the lipid metabolism disorder,inflammation and oxidative stress injury in ApoE^(-/-)***,targeted metabolomics demonstrated that PPC intervention altered the BA profile in mice by regulating the ratio of secondary BAs to primary BAs,and increased fecal BAs ***,quantitative polymerase chain reaction(qPCR)analysis showed that PPC intervention facilitated reverse cholesterol transport by upregulating Srb1 expression;In addition,PPC intervention promoted BA synthesis from cholesterol in liver by upregulating Cyp7a1 expression via suppression of the farnesoid X receptor(FXR)pathway,thus exhibiting a significant serum cholesterol-lowering *** summary,PPC attenuated HFD-induced AS in ApoE^(-/-)mice,which provides new insights into the design of novel and efficient anti-atherosclerotic strategies to prevent AS based on probiotics and prebiotics.

关键词： Atherosclerosis Pararabacteroides distasonis Oligomeric procyanidins Reverse cholesterol transport Bile acid metabolism

Impaired Spatial Firing Representations of Neurons in the Medial Entorhinal Cortex of the Epileptic Rat Using Microelectrode Arrays

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Research 2024年第2期2023卷 541-552页

作者： Zhaojie Xu Fan mo Gucheng Yang Penghui Fan Botao Lu Wei Liang Fanli Kong Luyi Jing Wei Xu Juntao liu Mixia Wang Yirong Wu Xinxia Cai State Key Laboratory of Transducer Technology Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Epilepsy severely impairs the cognitive behavior of *** remains unclear whether epilepsy-induced cognitive impairment is associated with neuronal activities in the medial entorhinal cortex(MEC),a region known for its involvement in spatial *** explore this neural mechanism,we recorded the spikes and local field potentials from MEC neurons in lithium-pilocarpine-induced epileptic rats using self-designed microelectrode *** the open field test,we identified spatial cells exhibiting spatially selective firing properties and assessed their spatial representations in relation to the progression of ***,we analyzed theta oscillations and theta modulation in both excitatory and inhibitory ***,we used a novel object recognition test to evaluate changes in spatial cognitive ability of epileptic *** the epilepsy modeling,the spatial tuning of various types of spatial cells had suffered a rapid and pronounced damage during the latent period(1 to 5 d).Subsequently,the firing characteristics and theta oscillations were *** the chronic period(>10 d),the performance in the novel object experiment *** conclusion,our study demonstrates the detrimental effect on spatial representations and electrophysiological properties of MEC neurons in the epileptic latency,suggesting the potential use of these changes as a"functional biomarker"for predicting cognitive impairment caused by epilepsy.

关键词： epilepsy impaired involvement

Prediction and validation of diffusive uptake rates for indoor volatile organic compounds in axial passive samplers

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Energy and Built Environment 2024年第1期5卷 24-31页

作者： Yan Wang Tao Yu Jinhan mo Department of Building Science Tsinghua UniversityBeijing 100084China Beijing Key Laboratory of Indoor Air Quality Evaluation and Control Beijing 100084China Wuhan Second Ship Design and Research Institute Wuhan 430205China School of Energy and Power Engineering Beihang UniversityBeijing 100191China Key Laboratory of Eco Planning&Green Building Ministry of Education(Tsinghua University)Beijing 100084China

The diffusive uptake rate is essential for using passive samplers to measure indoor volatile organic compounds(VOCs).The traditional theoretical model of passive samplers requires available regression formulas of uptake rates and physicochemical properties of adsorbents to predict the uptake ***,it is difficult to obtain the uptake rates of different VOCs under different sampling periods,and it is also difficult to obtain the physical parameters of adsorbents accurately and *** study provides a reliable numerical prediction method of diffusive uptake rates of *** modeling was based on the standard automated thermal desorption(ATD)tubes packed with Tenax TA and the mass transfer process during *** experimental determinations of toluene uptake rate are carried out to verify the prediction *** uptake rates of typical indoor VOCs are obtained from the literature to calibrate the key apparent parameters in the model by statistical regression *** predicted model can provide the VOC diffusive uptake rates under different sampling duration with an average deviation of less than 5%.This study can provide the basis for fast and accurate prediction of diffusive uptake rates for various VOC pollutants in built environments.

关键词： Indoor air quality Diffusive uptake rate Prediction model Sampling Adsorption

Individual and joint exposures to PMconstituents and mortality risk among the oldest-old in China

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Science China Life Sciences 2024年

作者： Yaqi Wang Yang Yuan Shaocai mo fang Wang Jing Wei Yao Yao Yi Zeng Yunquan Zhang Institute of Social Development and Health Management Hubei Province Key Laboratory of Occupational Hazard Identification and Control School of Public Health Wuhan University of Science and Technology Shenzhen Bao'an District Songgang People's Hospital School of Public Health Xuzhou Medical University Department of Atmospheric and Oceanic Science Earth System Science Interdisciplinary Center University of Maryland College Park China Center for Health Development Studies Peking University Center for Healthy Aging and Development Studies National School of Development Peking University

Cohort evidence linking long-term survival of older adults with exposure to fine particulate matter (PM2.5) constituents remains scarce in *** constructing a dynamic cohort based on the Chinese Longitudinal Healthy Longevity Study,we aimed to assess the individual and joint associations of major PM2.5constituents with all-cause death in Chinese oldest-old （≥80 years） ***-dependent Cox proportional hazards models were adopted to estimate death risks of long-term exposure to *** 14,884 participants,totaling 56,342 person-years of follow-up,12,346 deaths were *** highest mortality risk associated with an interquartile range（IQR） increase in exposure was 1.081 （95%confidence interval[CI]:1.055–1.108） for sulfate (IQR=4.1μg m–3),followed by 1.078 （95%CI:1.056–1.101） for black carbon (IQR=1.6μg m–3),1.056 （95%CI:1.028–1.084） for ammonium (IQR=3.2μg m–3),1.050 （95%CI:1.021–1.080） for nitrate (IQR=5.8μg m–3),and 1.049 （95%CI:1.024–1.074） for organic matter (IQR=10.3μg m–3).In joint exposure,each IQR-equivalent rise of all five PM2.5constituents was associated with an 8.2%（95%CI:4.0%–12.6%） increase in mortality *** weight analysis indicated the predominant role of sulfate and black carbon in driving PM2.5-related *** （aged 80–89 years） and rural dwellers were at significantly greater risk of mortality from individual and joint exposures to *** study suggests that later-life exposure to PM2.5constituents,particularly sulfate and black carbon,may curtail long-term survival of the oldest-old in China.

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Coupling Au with BO_(x) matrix induced by Closo-boron cluster for electrochemical synthesis of ammonia

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Journal of Energy Chemistry 2024年第6期93卷 471-477,I0012页

作者： Wenjing liu Nan Yang Yuao Wei Yingjie Yu Jie Chen mo Wei Yuting Huang Xiaohan Li Linghai Zhang Faisal Saleem Weina Zhang Haibo Zhang Fengwei Huo Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) School of Flexible Electronics(Future Technologies)Nanjing Tech UniversityNanjing 211816JiangsuChina College of Chemistry and molecular Sciences Wuhan UniversityWuhan 430072HubeiChina

Au is considered as one of the most promising catalysts for nitrogen reduction reaction(NRR),however maximizing the activity utilization rate of Au and understanding the synergistic effects between Au and carriers pose ongoing ***,we systematically explore the synergistic catalytic effect of incorporating Au with boron clusters for accelerating NRR *** in-situ abinitio strategy is employed to construct B-doped Au nanoparticles(2-6 nm in diameter)loaded on BO_(x) substrates(AuBO_(x)),in which B not only modulates the surface electronic structure of Au but also forms strong coupling interactions to stabilize the *** electrochemical results show that Au-BO_(x) possesses excellent NRR activity(NH_(3) yield of 48.52μg h^(-1)mg_(cat)^(-1),Faraday efficiency of 56.18%),and exhibits high stability and reproducibility throughout the electrocatalytic NRR *** calculations reveal that the introduction of B induces the formation of both Au dangling bond and Au-B coupling *** considerably facilitates the hydrogenation of~*N_(2)^(-)~*NH_(3).The present work provides a new avenue for the preparation of metal-boron materials achieved by one-step reduction and doping process,utilizing boron clusters as reducing and stabilizing agents.

关键词： Boron clusters Nitrogen reduction reaction Au–B coupling

Macrocyclic trichothecenes from Myrothecium verrucaria PA 57 and their cytotoxic activity

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Chinese Journal of Natural Medicines 2024年第9期22卷 854-863页

作者： mo Jisong TAN Yufen AI Wenjing LI Yunyun YUAN Yiyun JIANG Yueping XU Kangping TAN Guishan WANG Wenxuan LI Jing liu Shao Department of Pharmacy National Clinical Research Center for Geriatric DisordersXiangya HospitalCentral South UniversityChangsha 410008China Xiangya School of Pharmaceutical Sciences Central South UniversityChangsha 410008China

Four novel macrocyclic trichothecenes,termed mytoxins D-G(1-4),along with four known analogs(5-8),were isolated from the ethyl acetate extract of fermented rice inoculated with the fungus Myrothecium verrucaria *** compound features a tricyclic 12,13-epoxytrichothec-9-ene(EPT)***,mytoxin G(4)represents the first instance of a macrocyclic trichothecene incorporating a glucosyl unit within the trichothecene *** structures of the newly identified compounds were elucidated through comprehensive spectroscopic analysis combined with quantum chemical *** isolated compounds demonstrated cytotoxic activity against the CAL27 and HCT116 cell lines,which are models for human oral squamous cell carcinoma and colorectal cancer,***,mytoxin D(1)and mytoxin F(3)exhibited pronounced cytotoxic effects against both cancer cell lines,with IC_(50)values ranging from 3 to 6 nmol·L^(-1).moreover,compounds 1 and 3 were found to induce apoptosis in HCT116 cells by activating caspase-3.

关键词： Macrocyclic trichothecenes Myrothecium verrucaria Cytotoxicity Secondary metabolite Soil fungi

Transcriptional landscape of cotton roots in response to salt stress at single-cell resolution

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Plant Communications 2024年第2期5卷 46-66页

作者： Pengtao Li Qiankun liu Yangyang Wei Chaozhu Xing Zhongping Xu fang Ding Yuling liu Quanwei Lu Nan Hu Tao Wang Xiangqian Zhu Shuang Cheng Zhaoguo Li Zilin Zhao Yanfang Li Jiangping Han Xiaoyan Cai Zhongli Zhou Kunbo Wang Baohong Zhang fang.liu Shuangxia Jin Renhai Peng College of Biology and Food Engineering Anyang Institute of TechnologyAnyangHenan 455000China State Key Laboratory of Cotton Biology Institute of Cotton ResearchChinese Academy of Agricultural SciencesAnyangHenan 455000China Research Base Anyang Institute of TechnologyState Key Laboratory of Cotton BiologyAnyang 455000HenanChina School of Life Sciences Zhengzhou UniversityZhengzhouHenan 450001China Hubei Hongshan Laboratory National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina Hubei Key Laboratory of Plant Pathology Huazhong Agricultural UniversityWuhanHubei 430070China Department of Biology East Carolina UniversityGreenvilleNC 27858USA

Increasing soil salinization has led to severe reductions in plant yield and quality,and investigating the mo-lecular mechanism of salt stress response is therefore an urgent *** this study,we systematically analyzed the response of cotton roots to salt stress using single-cell transcriptomics technology;56281 high-quality cells were obtained from 5-day-old lateral root tips of Gossypium arboreum under natural growth conditions and different salt *** cell types with an array of novel marker genes were identified and confirmed by in situ RNA hybridization,and pseudotime analysis of some specific cell types revealed their potential differentiation *** changes in cell numbers under salt stress were observed for outer epidermal and inner endodermal cells,which were significantly enriched in response to stress,amide biosynthetic process,glutathione metabolism,and glycolysis/*** of differentially expressed genes identified in multiple comparisons revealed other functional ag-gregations concentrated on plant-type primary cell wall biogenesis,defense response,phenylpropanoid biosynthesis,and metabolic *** candidate differentially expressed genes encoding transcrip-tion factors or associated with plant hormones also responsive to salt stress were identified,and the func-tion of Ga03G2153,annotated as auxin-responsive GH3.6,was confirmed by virus-induced gene *** GaGH3.6-silenced plants showed a severe stress-susceptible phenotype,and physiological and biochemical measurements indicated that they suffered more significant oxidative *** results suggest that GaGH3.6 might participate in cotton salt tolerance by regulating redox *** thus construct a transcriptional atlas of salt-stressed cotton roots at single-cell resolution,enabling us to explore cellular heterogeneity and differentiation trajectories and providing valuable insights into the mo-lecular mechanisms that underlie plan

关键词： cotton salt stress scRNA-seq root cell types virus-induced gene silencing

Dynamic recrystallization behavior and strengthening mechanism of a novel mo-Ti_(3)AlC_(2) alloy at ultrahigh temperature

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Rare Metals 2024年第8期43卷 3946-3960页

作者： Lu Yang Xin-Yuan Zheng Yang Zhao Xi-Ran Wang fang-Nao Xiao Shi-Zhong Wei School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China National Joint Engineering Research Center for Abrasion Control and molding of Metal Materials Henan University of Science and TechnologyLuoyang 471003China Department of Applied Mechanics Univ.Bourgogne FrancheComteFEMTO-ST InstituteCNRS/UF/ENSMM/UTBM25000BesangonFrance

Increasing the recrystallization temperature to achieve better high-temperature performance is critical in the development of molybdenum alloys for ultrahightemperature applications,such as the newest generation of multitype high-temperature nuclear *** this study,an innovative strategy was proposed to improve the performance of molybdenum alloys at high temperature by using the two-dimensional MAX(where M is an early transition metal,A is an A-group element and X is C or N)ceramic material Ti_(3)AlC_(2).The relationships between flow stress,strain rate and temperature were *** microstructure,distribution of misorientation and evolution of dislocations in the mo-Ti_(3)AlC_(2) alloy were *** microscopic mechanism of the Ti_(3)AlC_(2) phase in the molybdenum alloy at high temperatures was *** experimental results showed that the peak flow stress of mo-Ti_(3)AlC_(2) at 1600℃ reached 155 MPa,which was161.8% greater than that of pure *** activation energy of thermal deformation of mo-Ti_(3)AlC_(2) was as large as537 kJ·mol~(-1),which was 17.6% more than that of pure *** recrystallization temperature reached 1600℃ or even *** topological reaction of the Ti_(3)AlC_(2) phase consumed a large amount of energy at high temperatures,resulting in increases in the deformation activation *** structures of AlTi_3 and Ti-O Magneli-phase oxides(Ti_nO_(2n-1)) were formed in-situ,which relied on kink bands and interlayer slip,resulting in many dislocations during ***,the special two-dimensional of the structure Ti_(3)AlC_(2) ceramic inhibited the recrystallization behavior of the mo *** results of this study can provide theoretical guidance for the development of a new generation of molybdenum alloys for use in ultrahigh-temperature environments.

关键词： mo alloy Two-dimensional reinforcement Dynamic recrystallization behavior Hot deformation Mechanical properties