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Radial growth in Qinghai spruce is most sensitive to severe drought in the Qilian Mountains of Northwest China

Journal of Forestry Research 2024年第3期35卷 73-86页

作者： Xuge wang liang Jiao Ruhong Xue Peng Zhang Dashi Du Mengyuan wei Qian li College of Geography and Environmental Science Northwest Normal UniversityNo.967Anning East RoadLanzhou 730070People's Republic of China Key Laboratory of Resource Environment and Sustainable Development of Oasis Northwest Normal UniversityLanzhou 730070Gansu ProvincePeople's Republicof China

Global warming and frequent extreme drought events lead to tree death and extensive forest decline,but the underlying mechanism is not *** drought years,cambial development is more sensitive to climate change,but in different phenological stages,the response rela-tionship is ***,the dynamic relationship between tree radial growth and climatic/environmental fac-tors needs to be *** thus continuously monitored radial growth of Qinghai spruce(Picea crassifolia Kom.)and environmental factors from January 2021 to November 2022 using point dendrometers and portable meteorological weather stations in the central area of the Qilian *** relationship and stability between the radial growth of Qinghai spruce and environmental factors were compared for different levels of drought in 2021 and *** year 2022 had higher temperatures and less precipitation and was drier than *** with 2021,the growing period in 2022 for Qinghai spruce was 10 days shorter,maximum growth rate(Grmax)was 4.5μm·d^(-1) slower,and the initiation of growth was 6 days *** of Qinghai spruce was always restricted by drought,and the stem radial increment(SRI)was more sensitive to precipitation and air relative *** changes in cumulative radial growth were divided into four phenological stages according to the time of growth onset,cessation,and maximum growth rate(Grmax)of Qinghai *** responses of SRI to climate change were stronger in Stage 3 and Stage 4 of 2021 and stronger in Stage 1(initiation growth stage)and Stage 3 of *** results provide important information on the growth of the trees in response to drought and for specific managing forests as the climate warms.

关键词： Picea crassifolia Radial growth dynamics Severe drought Response stability Point dendrometer

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Effects of drive imbalance on the particle emission from a Bose-Einstein condensate in a one-dimensional lattice

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Chinese Physics B 2024年第3期33卷 238-243页

作者：赖龙泉李照 School of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Electronic Engineering Chengdu Technological UniversityChengdu 611730China

Time-periodic driving has been an effective tool in the field of nonequilibrium quantum dynamics,which enables precise control of the particle *** investigate the collective emission of particles from a Bose-Einstein condensate in a one-dimensional lattice with periodic drives that are separate in modulation amplitudes and relative *** addition to the enhancement of particle emission,we find that amplitude imbalances lead to energy shift and band broadening,while typical relative phases may give rise to similar *** results offer insights into the specific manipulations of nonequilibrium quantum systems with tone-varying drives.

关键词： Bose-Einstein condensate particle emission periodic drive

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Construction of smart propellant with multi-morphologies

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Defence Technology（防务技术） 2024年第3期33卷 180-185页

作者： weitao Yang Yuchen Gao Rui Hu Manman li Fengqi Zhao He Jiang Xuan Zhang Xi’an Modern Chemistry Research Institute Xi’an710065China Northwestern Polytechnical University Xi’an710072China

Smart materials,which exhibit shape memory behavior in response to external stimuli,have shown great potential for use in biomedical *** this study,an energetic composite was fabricated using a UV-assisted DIw 3D printing technique and a shape memory material(SMP)as the *** composite has the ability to reduce the impact of external factors and adjust gun propellant combustion *** composition and 3D printing process were delineated,while the internal structure and shape memory performance of the composite material were *** energetic SMP composite exhibits an angle of reversal of 18 s at 70°,with a maximum elongation typically reaching up to 280% of the original length and a recovery length of approximately 105%during ten ***,thermal decomposition and combustion behavior were also demonstrated for the energetic SMP composite.

关键词： Smart material Gun propellants Multi-morphologies Self-regulation

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Structural properties of residual carbon in coal gasification fine slag and their influence on flotation separation and resource utilization:A review

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 217-230页

作者： Rui Han Anning Zhou Ningning Zhang Kaiqiang Guo Mengyan Cheng Heng Chen Cuicui li College of Chemistry and Chemical Engineering Xi’an University of Science and TechnologyXi’an 710054China Key Laboratory of Coal Resources Exploration and Comprehensive Utilization Ministry of Natural Resources of ChinaXi’an 710021China

Coal gasification fine slag(FS)is a typical solid waste generated in coal *** current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological *** recovery and the high-value utilization of residual carbon(RC)in FS are the keys to realizing the win-win situation of the coal chemical industry in terms of economic and environmental *** structural properties,such as pore,surface functional group,and microcrystalline structures,of RC in FS(FS-RC)not only affect the flotation recovery efficiency of FS-RC but also form the basis for the high-value utilization of *** this paper,the characteristics of FS-RC in terms of pore structure,surface functional groups,and microcrystalline structure are sorted out in accordance with gasification type and FS particle *** reasons for the formation of the special structural properties of FS-RC are analyzed,and their influence on the flotation separation and high-value utilization of FS-RC is *** methods based on the pore structural characterist-ics of FS-RC,such as ultrasonic pretreatment-pore-blocking flotation and pore breaking-flocculation flotation,are proposed to be the key development technologies for improving FS-RC recovery in the *** design of low-cost,low-dose collectors containing polar bonds based on the surface and microcrystalline structures of FS-RC is proposed to be an important breakthrough point for strengthening the flotation efficiency of FS-RC in the *** high-value utilization of FS should be based on the physicochemical structural proper-ties of FS-RC and should focus on the environmental impact of hazardous elements and the recyclability of chemical waste liquid to es-tablish an environmentally friendly utilization *** review is of great theoretical importance for the comprehensive understand-ing of the unique structural properties of FS-RC,the breakthrough of the technological bottleneck in the e

关键词： coal gasification fine slag residual carbon pore structure surface functional groups microcrystalline structure flotation sep-aration resource utilization

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Mechanism of Diabatic Heating on Precipitation and the Track of a Tibetan Plateau Vortex over the Eastern Slope of the Tibetan Plateau

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Advances in Atmospheric Sciences 2024年第1期41卷 155-172页

作者： Yuanchang DONG Guoping li Xiaolin XIE Long YANG Peiwen ZHANG Bo ZENG Institute of Plateau Meteorology China Meteorological Administration(CMA)/Heavy Rain and Drought-Flood Disaster in Plateau and Basin Key Laboratory of Sichuan ProvinceChengdu 610072China School of Atmospheric Sciences Chengdu University of Information TechnologyChengdu 610225China Meteorological Observation Data Center of Sichuan Province Chengdu 610072China Sichuan Branch of Meteorologist Training Institute CMAChengdu 610072China

Existing studies contend that latent heating(LH)will replace sensible heating(SH)to become the dominant factor affecting the development of the Tibetan Plateau vortex(TPV)after it moves off the Tibetan Plateau(TP).However,in the process of the TPV moving off the TP requires that the airmass traverse the eastern slope of the Tibetan Plateau(ESTP)where the topography and diabatic heating(DH)conditions rapidly *** LH gradually replaces SH to become the dominant factor in the development of the TPV over the ESTP is still not very *** this paper,an analysis of a typical case of a TPV with a long life history over the ESTP is performed by using multi-sourced meteorological data and model *** results show that SH from the TP surface can change the TPV-associated precipitation distribution by temperature advection after the TPV moves off the *** LH can then directly promote the development of the TPV and has a certain guiding effect on the track of the *** SH can control the active area of LH by changing the falling area of the TPV-associated precipitation,so it still plays a key role in the development and tracking of the TPV even though it has moved out of the main body of the TP.

关键词： eastern slope of the Tibetan Plateau diabatic heating Tibetan Plateau vortex precipitation distribution track

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Numerical study on the filtration characteristics of fine particles in granular bed filter at high temperature

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Particuology 2024年第10期93卷 41-53页

作者： Kangning Zhu Jie Cai Yuan li Xiaoyou Shen Jianfei Xi Yunjun wang Zhongzhu Gu School of Energy and Mechanical Engineering Nanjing Normal UniversityNanjing210023China

Granular bed filter(GBF)has become one of the current research hot topics due to its excellent performance in removing fine *** this paper,a three-dimensional fixed bed GBF filtration model was established and its accuracy was ***,the GBF filtration performance at high temperature were *** results demonstrate that elevating the temperature diminishes the filtration efficiency,albeit to a limited *** increasing of inlet gas velocity can significantly improve pressure drop for GBF and the filtration efficiency for fine particles of sizes larger than 5μ*** the diameter of stacked granular particle diameter grows,the filtration efficiency and pressure drop *** density of fine particles almost does not affect the filtration efficiency for fine particles of 1∼7μm,but a higher density leads to a higher filtration efficiency for fine particles of sizes bigger than 9μ***,as the fine particles size increases,the change of the filtration efficiency roughly goes through three stages:Stage 1:the filtration efficiency is basically unchanged;Stage 2:the filtration efficiency increases rapidly;Stage 3:the filtration efficiency increases steadily,but the rate of increase slows *** the increase of the fine particles Stokes number,the filtration efficiency of GBF will pass through two phases of stabilization and rapid increase.

关键词： Granular bed filter Fine particles High temperature Filtration efficiency

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Synthesis of straight-chain C_(49)H_(100) alkane using a modular splicing strategy

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Journal of Energy Chemistry 2024年第5期92卷 414-421页

作者： Bing Ma Jingqing Tian Xueling Lang Shutao Lei Bolong li Chen Zhao Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China School of Materials Science and Engineering Nankai UniversityTianjin 300350China

Ultra-long n-alkanes are highly valuable in both scientific research and as major constituents of specialty high-melting-point *** conventional methods(e.g.,Fischer–Tropsch(FT),ethylene oligomerization,and polyethylene cracking)typically resulting in wide n-alkane distributions,the elaborate design strategy presented herein allows the direct synthesis of pure,long n-alkanes using a modular splicing method with acetone,furfural,and fatty acid anhydrides or acyl chlorides as *** herein approach is based on a simple four-step catalytic reaction scheme involving C–C chain elongation and C–O bond *** synthesized pure n-alkanes had a carbon chain length as high as C_(49)(total yield of 49%).The synthesis approach also allows to selectively prepare n-alkanes with even and odd carbon numbers ranging from C15 to C_(49).This process represents a great breakthrough in the synthesis of long-chain pure n-alkanes,surpassing the carbon number limitations reported in previous methodologies.

关键词： Straight-chain alkane Aldol condensation F-Cacylation Hydrodeoxygenation

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Paclitaxel-induced Immune Dysfunction and Activation of Transcription Factor AP-1 Facilitate Hepatitis B Virus Replication

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Journal of Clinical and Translational Hepatology 2024年第5期12卷 457-468页

作者： Shi Chen Benhua li wei Luo Adeel ur Rehman Miao He Qian Yang Shunyao wang Jinjun Guo ling Chen Xiaosong li Clinical Molecular Medicine Testing Center The First Affiliated HospitalChongqing Medical UniversityChongqingChina Affiliated Traditional Chinese Medicine Hospital of Southwest Medical University LuzhouSichuanChina Laboratory Animal Center of Chongqing Medical University ChongqingChina Bishan Hospital of Chongqing Bishan Hospital of Chongqing Medical UniversityChongqingChina The Center of Experimental Teaching Management Chongqing Medical UniversityChongqingChina

Background and Aims:Hepatitis B virus(HBV)reactivation is commonly observed in individuals with chronic HBV infection undergoing antineoplastic drug ***(PTX)treatment has been identified as a potential trigger for HBV *** study aimed to uncover the mechanisms of PTX-induced HBV reactivation in vitro and in vivo,which may inform new strategies for HBV antiviral ***:The impact of PTX on HBV replication was assessed through various methods including enzyme-linked immunosorbent assay,dual-luciferase reporter assay,quantitative real-time PCR,chromatin immunoprecipitation,and immunohistochemical *** sequencing and 16S rRNA sequencing were employed to assess alterations in the transcriptome and microbial diversity in PTX-treated HBV transgenic ***:PTX enhanced the levels of HBV 3.5-kb mRNA,HBV DNA,HBeAg,and HBsAg both in vitro and in *** also promoted the activity of the HBV core promoter and transcription factor *** of AP-1 gene expression markedly suppressed PTX-induced HBV *** sequencing revealed that PTX activated the immune-related signaling networks such as IL-17,NF-􀇉B,and MAPK signaling pathways,with the pivotal common key molecule being *** 16S rRNA sequencing revealed that PTX induced dysbiosis of gut ***:PTX-induced HBV reactivation was likely a synergistic outcome of immune suppression and direct stimulation of HBV replication through the enhancement of HBV core promoter activity mediated by the transcription factor *** findings propose a novel molecular mechanism,underscoring the critical role of AP-1 in PTX-induced HBV reactivation.

关键词： Paclitaxel HBV reactivation Transcription factor AP-1 Immune system Gut microbiota

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A simplified dispersion-compensation microstructure fiber with seven cores

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Optoelectronics Letters 2024年第4期20卷 216-221页

作者： li wenchao wANG Chao YANG Hongda HANG Ying wANG wei Intelligence and Information Engineering College Tangshan UniversityTangshan 063000China School of Information Science and Engineering Yanshan UniversityQinhuangdao 066004China

In order to compensate the dispersion accumulated in a single mode fiber(SMF)for higher communication capacity,a simplified dispersion-compensation microstructure fiber(DC-MSF)with seven cores is proposed in this *** fiber’s cladding is made of pure silica without air holes,and its outer cores are composed of six germanium up-doped cylinders,which has the advantage of simple *** finite element method(FEM)and beam propagation method(BPM)are used to study the properties of the fiber,and the relationship between the structural parameters of the fiber and the dispersion,as well as the phase matching wavelength,is *** optimizing the structural parameters of the fiber,the dispersion of the fiber can reach-5291.47 ps·nm^(-1)·km^(-1) at 1550 nm,and the coupling loss to the conventional single-mode fiber is only 0.137 d *** with the conventional dispersion-compensation fiber,the fiber has lots of advantages,such as single mode transmission,easy to fabricate and low coupling loss with traditional SMF,etc.

关键词： fiber dispersion simplified

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Stromal thrombospondin 1 suppresses angiogenesis in oral submucous fibrosis

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International Journal of Oral Science 2024年第1期16卷 163-172页

作者： Xiao Yang Hui Zhao Rui li Yang Chen Zhi Xu Zhengjun Shang State Key Laboratory of Oral&Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Ministry of EducationHubei Key Laboratory of StomatologySchool&Hospital of StomatologyWuhan UniversityWuhanChina Department of Oral and Maxillofacial-Head and Neck Oncology School of Stomatology–Hospital of StomatologyWuhan UniversityWuhanChina Department of Stomatology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina

A decline in mucosal vascularity is a histological hallmark of oral submucous fibrosis (OSF), a premalignant disease that is largely induced by betel quid chewing. However, the lack of available models has challenged studies of angiogenesis in OSF. Here, we found that the expression of thrombospondin 1 (THBS1), an endogenous angiostatic protein, was elevated in the stroma of tissues with OSF. Using a fibroblast-attached organoid (FAO) model, the overexpression of THBS1 in OSF was stably recapitulated in vitro. In the FAO model,treatment with arecoline, a major pathogenic component in areca nuts, enhanced the secretion of transforming growth factor (TGF)-β1 by epithelial cells, which then promoted the expression of THBS1 in fibroblasts. Furthermore, human umbilical vein endothelial cells (HUVECs)were incorporated into the FAO to mimic the vascularized component. Overexpression of THBS1 in fibroblasts drastically suppressed the sprouting ability of endothelial cells in vascularized FAOs (v FAOs). Consistently, treatment with arecoline reduced the expression of CD31in v FAOs, and this effect was attenuated when the endothelial cells were preincubated with neutralizing antibody of CD36, a receptor of THBS1. Finally, in an arecoline-induced rat OSF model, THBS1 inhibition alleviated collagen deposition and the decline in vascularity in vivo. Overall, we exploited an assembled organoid model to study OSF pathogenesis and provide a rationale for targeting THBS1.

关键词： angiogenesis elevated endogenous

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