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Scientific Advances and Weather Services of the China Meteorological Administration’s National Forecasting Systems during the Beijing 2022 Winter Olympics
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作者 Guo DENG Xueshun SHEN +23 位作者 jun du Jiandong GONG Hua TONG Liantang DENG Zhifang XU Jing CHEN Jian SUN Yong WANG Jiangkai HU Jianjie WANG Mingxuan CHEN Huiling YUAN Yutao ZHANG Hongqi LI Yuanzhe WANG Li GAO Li SHENG Da LI Li LI Hao WANG Ying ZHAO Yinglin LI Zhili LIU Wenhua GUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期767-776,共10页
Since the Beijing 2022 Winter Olympics was the first Winter Olympics in history held in continental winter monsoon climate conditions across complex terrain areas,there is a deficiency of relevant research,operational... Since the Beijing 2022 Winter Olympics was the first Winter Olympics in history held in continental winter monsoon climate conditions across complex terrain areas,there is a deficiency of relevant research,operational techniques,and experience.This made providing meteorological services for this event particularly challenging.The China Meteorological Administration(CMA)Earth System Modeling and Prediction Centre,achieved breakthroughs in research on short-and medium-term deterministic and ensemble numerical predictions.Several key technologies crucial for precise winter weather services during the Winter Olympics were developed.A comprehensive framework,known as the Operational System for High-Precision Weather Forecasting for the Winter Olympics,was established.Some of these advancements represent the highest level of capabilities currently available in China.The meteorological service provided to the Beijing 2022 Games also exceeded previous Winter Olympic Games in both variety and quality.This included achievements such as the“100-meter level,minute level”downscaled spatiotemporal resolution and forecasts spanning 1 to 15 days.Around 30 new technologies and over 60 kinds of products that align with the requirements of the Winter Olympics Organizing Committee were developed,and many of these techniques have since been integrated into the CMA’s operational national forecasting systems.These accomplishments were facilitated by a dedicated weather forecasting and research initiative,in conjunction with the preexisting real-time operational forecasting systems of the CMA.This program represents one of the five subprograms of the WMO’s high-impact weather forecasting demonstration project(SMART2022),and continues to play an important role in their Regional Association(RA)II Research Development Project(Hangzhou RDP).Therefore,the research accomplishments and meteorological service experiences from this program will be carried forward into forthcoming highimpact weather forecasting activities.This article provides an overview and assessment of this program and the operational national forecasting systems. 展开更多
关键词 Beijing Winter Olympic Games CMA national forecasting system data assimilation ensemble forecast bias correction and downscaling machine learning-based fusion methods
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3,6-二(3,5-二甲基吡唑-1-基)-1,2-二氢-1,2,4,5-四嗪合成方法优化及过程探究
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作者 范思绮 王桂龙 +5 位作者 冯鑫 段晓霞 陈杰 杜军 杨超 詹发禄 《过程工程学报》 北大核心 2025年第10期1075-1087,共13页
3,6-二(3,5-二甲基吡唑-1-基)-1,2-二氢-1,2,4,5-四嗪(DHBT)是合成四嗪类含能材料的前体化合物。本研究以自制三氨基胍盐酸盐为原料,与乙酰丙酮通过成环反应制备DHBT。使用新建立的高效液相色谱方法定量分析该反应的动力学过程,表征反... 3,6-二(3,5-二甲基吡唑-1-基)-1,2-二氢-1,2,4,5-四嗪(DHBT)是合成四嗪类含能材料的前体化合物。本研究以自制三氨基胍盐酸盐为原料,与乙酰丙酮通过成环反应制备DHBT。使用新建立的高效液相色谱方法定量分析该反应的动力学过程,表征反应过程中产生的中间体1,1'-(3,5-二甲基-吡唑-1基)-烯胺肼,并基于该中间体提出DHBT关环反应机理。随后对间歇釜式合成DHBT的反应条件进行优化,探究反应器类型、搅拌方式、反应物浓度配比、反应温度和溶剂种类对DHBT收率的影响。结果表明,在采用带内挡板的250 mL玻璃夹套釜和斜叶搅拌桨,转速400 r/min,反应体系中加入5.0倍原料质量的去离子水与2.0倍原料摩尔量的乙酰丙酮,并在70℃下反应2 h的条件下,DHBT的实际收率达77.5%,产品纯度为96.3%。在该优选条件基础上,进一步完成480 g级放大合成,收率达到72.9%。动力学研究显示,反应决速步为中间体向产品的转化过程,对70~90℃下以中间体为起点的环化过程分析表明,该反应遵循二级反应动力学,表观活化能E_(a)=112.66 kJ/mol,指前因子A=1.64×10^(18)mol/(L·min),线性相关系数R^(2)=0.9967。此外,结合反应量热仪对反应过程进行量热测试,测得化学反应焓变△_(r)H_(m)=364.03 kJ/mol。 展开更多
关键词 3 6-二(3 5-二甲基吡唑-1-基)-1 2-二氢-1 2 4 5-四嗪 三氨基胍盐酸盐 高效液相色谱 反应动力学 反应热
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Energy transfer enhanced photocatalytic hydrogen evolution in organic heterostructure nanoparticles via flash nanoprecipitation processing 被引量:1
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作者 Miaojie Yu Weiwei Zhang +4 位作者 Xueyan Liu Guohui Zhao jun du Yongzhen Wu Wei-Hong Zhu 《Green Energy & Environment》 2025年第2期390-398,共9页
Organic nanophotocatalysts are promising candidates for solar fuels production,but they still face the challenge of unfavorable geminate recombination due to the limited exciton diffusion lengths.Here,we introduce a b... Organic nanophotocatalysts are promising candidates for solar fuels production,but they still face the challenge of unfavorable geminate recombination due to the limited exciton diffusion lengths.Here,we introduce a binary nanophotocatalyst fabricated by blending two polymers,PS-PEG5(PS)and PBT-PEG5(PBT),with matched absorption and emission spectra,enabling a Forster resonance energy transfer(FRET)process for enhanced photocatalysis.These heterostructure nanophotocatalysts are processed using a facile and scalable flash nanoprecipitation(FNP)technique with precious kinetic control over binary nanoparticle formation.The resulting nanoparticles exhibit an exceptional photocatalytic hydrogen evolution rate up to 65 mmol g^(-1) h^(-1),2.5 times higher than that single component nanoparticles.Characterizations through fluorescence spectra and transient absorption spectra confirm the hetero-energy transfer within the binary nanoparticles,which prolongs the excited-state lifetime and extends the namely“effective exciton diffusion length”.Our finding opens new avenues for designing efficient organic photocatalysts by improving exciton migration. 展开更多
关键词 Polymer photocatalysts NANOPARTICLES Hydrogen evolution Forster resonance energy transfer
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Evaluation of two algorithms measuring homologous recombination deficiency status in prognostic assessment for treatment-naive non-small cell lung cancer
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作者 Yidan Ma Jingyu Huang +13 位作者 Lei He jun du Longteng Liu Xiaoguang Li Peng Jiao Xiaonan Wu Wei Zhou Xiaomao Xu Li Yang Jing Di Changbin Zhu Lin Li Dongge Liu Zheng Wang 《Chinese Journal of Cancer Research》 2025年第3期352-364,共13页
Objective:Patients with homologous recombination deficiency(HRD)demonstrate distinct clinicopathological and prognostic features.However,standardised and clinically validated HRD detection methodologies specifically t... Objective:Patients with homologous recombination deficiency(HRD)demonstrate distinct clinicopathological and prognostic features.However,standardised and clinically validated HRD detection methodologies specifically tailored for non-small cell lung cancer(NSCLC)have yet to be established.Further research is needed to clarify the precise role and clinical implications of HRD in NSCLC.Methods:A cohort of 580 treatment-naive NSCLC patients was retrospectively enrolled.Comprehensive genomic profiling(CGP)was performed for all patients,and HRD status was evaluated using two genomic scar score(GSS)-based algorithms:a machine learning-based GSS(ML-GSS)and a continuous linear regression-based GSS(CLR-GSS).To assess the diagnostic performance(sensitivity and specificity)of the ML-GSS and CLR-GSS algorithms for HRD detection,immunohistochemical(IHC)staining was conducted for two HRD-related biomarkers:Schlafen 11(SLFN11)and RAD51.Survival analysis,including progression-free survival(PFS),along with multivariable Cox proportional hazards models,was performed to compare the prognostic value of the two HRD algorithms.Results:Among all patients,146(25.2%)and 46(7.9%)were classified as HRD-positive(HRD+)by ML-GSS and CLR-GSS,respectively.Using SLFN11 IHC expression as the reference standard,comparative analysis demonstrated that ML-GSS exhibited significantly higher sensitivity but lower specificity than CLR-GSS.This trend was consistently observed in RAD51 staining analysis.Compared to HRD-negative(HRD-)patients,MLGSS-defined HRD+cases displayed distinct clinicopathological and genomic features,including a higher prevalence of homologous recombination(HR)-related genes mutations,BRCA1/2 mutations,TP53 mutations,elevated tumor mutation burden(TMB),and increased copy number variations(CNVs).In contrast,CLR-GSSdefined HRD+patients were only enriched for BRCA1/2 mutations,TP53 mutations,and elevated TMB.Furthermore,ML-GSS-defined HRD+status was associated with significantly worse prognosis following first-line therapy compared to HRD-patients.Univariate and multivariable Cox analyses identified ML-GSS-defined HRD+and TP53 mutations as significant predictors and independent risk factors,respectively.No such associations were observed in the CLR-GSS-defined HRD+cohort.Conclusions:ML-GSS demonstrated superior performance to CLR-GSS in assessing chromosomal instability(CIN)and showed greater clinical utility.We recommend the ML-GSS algorithm as a robust and clinically validated tool for HRD/CIN evaluation in NSCLC.Furthermore,ML-GSS-defined HRD+status was identified as both a significant predictor and an independent risk factor. 展开更多
关键词 Non-small cell lung cancer homologous recombination deficiency methodology TP53 PROGNOSIS
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Revealing the heterogeneous nucleation mechanism of Mg_(17)Al_(12)on impurity Mg_(2)Si particles in commercial AZ31 alloy
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作者 Liling Mo Hengbin Liao +2 位作者 Linbo Chen Yu-jun Zhao jun du 《Journal of Magnesium and Alloys》 2025年第7期3122-3133,共12页
Silicon(Si)is an inevitable impurity element in the AZ31 alloy.In this study,the Si impurity was detected mainly as fine Mg_(2)Si particles dispersed widely within the central region of the Mg_(17)Al_(12) phase.During... Silicon(Si)is an inevitable impurity element in the AZ31 alloy.In this study,the Si impurity was detected mainly as fine Mg_(2)Si particles dispersed widely within the central region of the Mg_(17)Al_(12) phase.During the solidification process,the Mg_(2)Si particle precipitates at about 565℃,before the Mg_(17)Al_(12) phase of 186℃,potentially acting as the heterogeneous nucleation core for the Mg_(17)Al_(12) phase.The orientation relationship between Mg_(2)Si and Mg_(17)Al_(12) was investigated using the Edge-to-Edge matching model(E2EM)calculations,which showed a misfit of only 0.1%.This low misfit suggests that Mg_(2)Si can serve as a heterogeneous nucleation site for Mg_(17)Al_(12).The surface and interface structures of Mg_(2)Si(220)and Mg_(17)Al_(12)(332)were constructed,and then investigated through the first-principles calculation.The theoretical results indicate that Mg and Al are easily adsorbed on the surface of Mg_(2)Si,with Al showing higher adsorption energy than Mg.Furthermore,the interface between Mg_(2)Si and Mg_(17)Al_(12) exhibits favorable thermodynamic stability.Combined with experiments and theoretical calculations,it is confirmed that the Mg_(2)Si particles,formed due to the Si impurity,provide effective heterogeneous nucleation sites for the Mg_(17)Al_(12) phase. 展开更多
关键词 AZ31 alloy Heterogeneous nucleation Mg_(17)Al_(12)phase Mg_(2)Si particle First-principles calculation
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Effect of Sr modification on microstructure and thermal conductivity of hypoeutectic Al−Si alloys 被引量:27
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作者 jun-qi GAN Yu-jian HUANG +1 位作者 Cheng WEN jun du 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第11期2879-2890,共12页
Trace amount of Sr(0.05 wt.%)was added into the hypoeutectic Al−Si(3−12 wt.%Si)alloys to modify their microstructure and improve thermal conductivity.The results showed that the thermal conductivity of hypoeutectic Al... Trace amount of Sr(0.05 wt.%)was added into the hypoeutectic Al−Si(3−12 wt.%Si)alloys to modify their microstructure and improve thermal conductivity.The results showed that the thermal conductivity of hypoeutectic Al−Si alloys was improved by Sr modification,and the increment and increasing rate of the thermal conductivity gradually increased with Si content increasing.The improvement of thermal conductivity was primarily related to the morphology variation of eutectic Si phases.In Sr-modified Al−Si alloys,the morphology of eutectic Si phases was a mixed morphology of fiber structure and fine flaky structure,and the proportion of the fine flaky eutectic Si phases gradually decreased with Si content increasing.Under the Si content reaching 9 wt.%,the proportion of fine flaky eutectic Si phases was nearly negligible in Sr-modified alloys.Correspondingly,the increment and increasing rate of thermal conductivity of Sr-modified alloys reached the maximum and tended to be stable. 展开更多
关键词 hypoeutectic Al−Si alloy Sr modification eutectic Si morphology thermal conductivity Al/Si interface
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Design and preparation of Al-Fe-Ce ternary aluminum alloys with high thermal conductivity 被引量:5
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作者 Gan LUO Xiong ZHOU +2 位作者 Cheng-bo LI jun du Zheng-hua HUANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第6期1781-1794,共14页
Ce element was introduced to modify Al−2%Fe(mass fraction)binary alloy.The microstructures,crystallization behavior,electrical/thermal conductivities and mechanical properties of these alloys were systematically inves... Ce element was introduced to modify Al−2%Fe(mass fraction)binary alloy.The microstructures,crystallization behavior,electrical/thermal conductivities and mechanical properties of these alloys were systematically investigated.The results indicated that the appropriate Ce addition decreased the recalescence temperature and growth temperature of Al−Fe eutectic structure,improved the morphology and distribution of Fe-containing phase,and simultaneously increased the conductivity and mechanical properties.The annealed treatment improved the thermal conductivity of these alloys due to the decreasing concentration of point defects.Rolling process further broke up the coarser Fe-containing phases into finer particles and made the secondary phases uniformly distributed in theα(Al)matrix.After subsequent annealing treatment and rolling deformation,the thermal conductivity,ultimate tensile strength and hardness of the Al−2%Fe−0.3%Ce(mass fraction)alloy reached 226 W/(m·K),(182±1.4)MPa and HBW(49.5±1.7),respectively. 展开更多
关键词 Al−Fe−Ce alloys Ce modification thermal conductivity mechanical properties
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Activation of Rac1-PI3K/Akt is required for epidermal growth factorinduced PAK1 activation and cell migration in MDA-MB-231 breast cancer cells 被引量:3
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作者 Yu Yang jun du +5 位作者 Zhenzhen Hu Jiaojing Liu Yinhui Tian Yichao Zhu Le Wang Luo Gu 《The Journal of Biomedical Research》 CAS 2011年第4期237-245,共9页
Epidermal growth factor (EGF) may increase cell motility, an event implicated in cancer cell invasion and metastasis. However, the underlying mechanisms for EGF-induced cell motility remain elusive. In this study, w... Epidermal growth factor (EGF) may increase cell motility, an event implicated in cancer cell invasion and metastasis. However, the underlying mechanisms for EGF-induced cell motility remain elusive. In this study, we found that EGF treatment could activate Ras-related C3 botulinum toxin substrate 1 (Racl), PI3K/Akt and p21- actived kinase (PAK1) along with cell migration. Ectopic expression of PAK1 K299R, a dominant negative PAK1 mutant, could largely abolish EGF-induced cell migration. Blocking PI3K/Akt signalling with LY294002 or Akt siRNA remarkably inhibited both EGF-induced PAK1 activation and cell migration. Furthermore, expression of dominant-negative Racl (T17N) could largely block EGF-induced PI3K/Akt-PAK1 activation and cell migration. Interestingly, EGF could induce a significant production of ROS, and N-acetyl-L-cysteine, a scavenger of ROS which abolished the EGF-induced ROS generation, cell migration, as well as activation of PI3K/Akt and PAK, but not Racl. Our study demonstrated that EGF-induced cell migration involves a cascade of signalling events, including activation of Racl, generation of ROS and subsequent activation of PI3K/Akt and PAK1. 展开更多
关键词 breast cancer cell epidermal growth factor migration Ras-related C3 botulinum toxin substrate 1(Rac1) PI3K/AKT p21-actived kinase (PAK1)
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Revealing the nucleation event of Mg-Al alloy induced by Fe impurity 被引量:3
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作者 Hengbin Liao Liling Mo +2 位作者 Xiong Zhou Zhizhong Yuan jun du 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第7期1317-1321,共5页
This study revealed the nucleation event and grain refinement mechanism of Mg-Al alloy induced by Fe impurity.The following orientation relationship was observed between Al-Fe particle andα-Mg matrix in the Mg-3Al al... This study revealed the nucleation event and grain refinement mechanism of Mg-Al alloy induced by Fe impurity.The following orientation relationship was observed between Al-Fe particle andα-Mg matrix in the Mg-3Al alloy containing Fe impurity using a focused ion beam aided transmission electron microscope technique:(1^(-)011)[011^(-)1]_(Mg)//(011^(-))[011]_(Al_(2)Fe).Mg-3Al alloy was inoculated by adding 0.02wt%Fe to verify the nucleating potency of the Al_(2)Fe phase forα-Mg grain.The results indicated that Mg-3Al alloy was effectively refined with an average grain size declining from 1135 to 540μm.Among the potential Al-Fe phases of Mg-3Al-0.02Fe alloy,only the precipitation of the Al_(2)Fe phase occurs earlier than that ofα-Mg grain,and the Al_(2)Fe phase is stable in the nucleation stage ofα-Mg grain.Therefore,the Al_(2)Fe particle is the only available nucleating site for Mg-Al alloy with Fe impurity.The heterogeneous nucleation event ofα-Mg grain on the Al_(2)Fe particle is responsible for the grain refinement of Mg-3Al alloy inoculated by Fe. 展开更多
关键词 grain refinement Mg-Al alloy Al-Fe particle heterogeneous nucleation
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Activation of p38/HSP27 pathway counters melatonin-induced inhibitory effect on proliferation of human gastric cancer cells
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作者 Chenchen Zhu Haonan Jiang +5 位作者 Wenjie Deng Shuo Zhao Kaiquan Li Yuting Wang Qinjun Wei jun du 《The Journal of Biomedical Research》 CAS CSCD 2019年第5期317-324,共8页
Overexpression of heat shock protein 27(HSP27)in gastric cancer is correlated with poor clinical prognosis.Melatonin,an endogenous hormone,shows promise in gastric cancer therapy.However,there is limited study on the ... Overexpression of heat shock protein 27(HSP27)in gastric cancer is correlated with poor clinical prognosis.Melatonin,an endogenous hormone,shows promise in gastric cancer therapy.However,there is limited study on the biological activity of HSP27 in response to melatonin treatment.In this study,we show an anti-proliferative action of melatonin on human gastric cancer cell lines BGC-823 and MGC-803.Biochemically,the inhibitory effect of melatonin is accompanied by the upregulation of HSP27 phosphorylation level.Transfection of gastric cancer cells with HSP27-specific siRNA effectively reduces HSP27 phosphorylation and potentiated melatonininduced inhibitory effect on cell proliferation.The reduction of cyclin D1 in melatonin-treated cells is also aggravated by HSP27 depletion.Moreover,melatonin stimulation increases p38 phosphorylation.Pretreatment with p38 inhibitor SB203580 not only remarkably suppresses melatonin-induced HSP27 phosphorylation,but also augment the inhibitory effect of melatonin on cyclin D1 expression as well as cell proliferation.Taken together,our study indicates the protective pathway of p38/HSP27 against melatonin-induced inhibitory effect on gastric cancer cell proliferation,suggesting that combined with p38/HSP27 pathway inhibitor,the therapeutic efficacy of melatonin on gastric cancer may be improved. 展开更多
关键词 MELATONIN P38 HSP27 gastric cancer PROLIFERATION
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α-fetoprotein involvement during glucocorticoid-induced precocious maturation in rat colon
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作者 Min Chen Peng Sun +4 位作者 Xiao-Yan Liu Dan Dong jun du Luo Gu Ying-Bin Ge 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第24期2933-2940,共8页
AIM: TO investigate the role of a-fetoprotein (AFP), a cancer-associated fetal glycoprotein, in glucocorticoidinduced precocious maturation in rat colon. METHODS: Colons from suckling Sprague-Dawley rats were used... AIM: TO investigate the role of a-fetoprotein (AFP), a cancer-associated fetal glycoprotein, in glucocorticoidinduced precocious maturation in rat colon. METHODS: Colons from suckling Sprague-Dawley rats were used in this study. Corticosterone acetate at a dose of 100 μg/g body weight was given to normal pups on days 7, 9 and 11 after birth to induce hypercorticoidism. Control animals were injected with identical volumes of normal saline. Some rats receiving corticosterone 7 d after birth were also treated with mifepristone (RU38486), a glucocorticoid cytoplasm receptor antagonist to investigate the effects of glucocorticoids (GCs). The morphological changes of the crypt depth and villous height of the villous zone in colon were observed as indicesof colon maturation. Expression levels of AFP in colons were detected by reverse transcriptase polymerase chain reaction and Western blotting. To identify the cellular lo- calization of AFP in developing rat colons, double-immu- nofluorescent staining was performed using antibodies to specific mesenchymal cell marker and AFP. RESULTS: Corticosterone increased the crypt depth and villous height in the colon of 8- and 10-d-old rats with hypercorticoidism compared with that in the control ani- mals (120% in 8-d-old rats and 118% in 10-d-old rats in villous height, P = 0.021; 145% in 8-d-old rats and 124% in 10-d-old rats in crypt depth, P = 0.017). These increases were accompanied by an increase of AFP ex- pression in both mRNA and protein (2.5-folds in 8-d- old and 2.5-folds in 10-d-old rats higher than in control animals, P = 0.035; 1.8-folds in 8-d-old and 1.3-folds in 10-d-old rats higher than in control animals, P = 0.023). Increased crypt depth and villous height and increased expression of AFP in the colon of rats with hypercorti- coidism were blocked by mifepristone. Both had positive staining for AFP or vimentin, and overlapped in mesen- chymal cells at each tested colon. CONCLUSION: GCs promote the development of rat colon. AFP appears to be involved, in part, in mediating the effects of GCs in the developmental colon. 展开更多
关键词 GLUCOCORTICOIDS a-fetoprotein Precociousmaturation COLON Rat
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Comparison of precipitation products to observations in Tibet during the rainy season
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作者 Zhuo Ga Za dui +1 位作者 duodian Luozhu jun du 《Research in Cold and Arid Regions》 CSCD 2018年第5期392-403,共12页
Precipitation is an important component of global water and energy transport and a major aspect of climate change. Due to the scarcity of meteorological observations, the precipitation climate over Tibet has been insu... Precipitation is an important component of global water and energy transport and a major aspect of climate change. Due to the scarcity of meteorological observations, the precipitation climate over Tibet has been insufficiently documented. In this study, the distribution of precipitation during the rainy season over Tibet from 1980 to 2013 is described on monthly to annual time scales with meteorological observations. Furthermore, four precipitation products are compared to observations over Tibet. These datasets include products derived from the Asian Precipitation-Highly-Resolved Observational Data(APHRO), the Global Precipitation Climatology Centre(GPCC), the University of Delaware(UDel), and the China Meteorological Administration(CMA). The error, relative error, standard deviation, root-mean-square error, correlations and trends between these products for the same period are analyzed with in situ precipitation during the rainy season from May to September. The results indicate that these datasets can broadly capture the temporal and spatial precipitation distribution over Tibet. The precipitation gradually increases from northwest to southeast. The spatial precipitation in GPCC and CMA are similar and positively correlated to observations. Areas with the largest deviations are located in southwestern Tibet along the Himalayas. The APHRO product underestimates, while the UDel, GPCC, and CMA datasets overestimates precipitation on the basis of monthly and inter-annual variation. The biases in GPCC and CMA are smaller than those in APHRO and UDel with a mean relative error lower than 10% during the same periods. The linear trend of precipitation indicates that the increase in precipitation has accelerated extensively during the last 30 years in most regions of Tibet. The CMA generally achieves the best performance of these four precipitation products. Data uncertainty in Tibet might be caused by the low density of stations, complex topography between the grid points and stations, and the interpolation methods, which can also produce an obvious difference between the gridded data and observations. 展开更多
关键词 APHRO GPCC UDel CMA TIBET PRECIPITATION
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Study on the Reasons and Countermeasures for Loss of Listed Companies in Manufacturing Industry
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作者 Yong du jun du Bo YAN 《Asian Agricultural Research》 2013年第12期21-24,29,共5页
In combination with the data of loss-making listed companies in manufacturing industry at capital market in 2008-2010,this paper analyzed the characteristics of loss of listed companies.Major reasons include the blind... In combination with the data of loss-making listed companies in manufacturing industry at capital market in 2008-2010,this paper analyzed the characteristics of loss of listed companies.Major reasons include the blind investment of management personnel,low operation and management level,blind pursuit of diversified operation,improper stock right structure,weak supervision of government,and imperfect delisting system.Finally,it came up with some countermeasures,including improving quality of management personnel,management personnel selecting proper investment projects,strengthening internal management of enterprise,implementing effective asset rearrangement,setting up effective incentive and restrictive mechanism,bringing into play regulation function of banks,improving delisting mechanism,reducing centralization of state owned stock right,and establishing and improving market information disclosure system. 展开更多
关键词 Manufacturing industry LISTED COMPANIES LOSS Reaso
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Mechanism prediction of Astragalus mongholicus Bunge and Angelica sinensis Diels in treating interstitial lung disease based on network pharmacology and molecular docking
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作者 jun du Jian Hao Wei Wei 《TMR药理学研究》 2023年4期1-9,共9页
Objective:To investigate the mechanism by which Astragalus mongholicus Bunge(AM),and Angelica sinensis Diels(AS)act in interstitial lung disease(ILD)based on computational prediction.Methods:We screened the ingredient... Objective:To investigate the mechanism by which Astragalus mongholicus Bunge(AM),and Angelica sinensis Diels(AS)act in interstitial lung disease(ILD)based on computational prediction.Methods:We screened the ingredients of AM and AS in PubMed,the Web of Science,China National Knowledge Infrastructure(CNKI)Databases,etc.Then obtained the potential effective components.By sharing the same molecular with ILD,we got the possible target genes for ILD treatment and constructed components–targets–disease network with Cytoscape software.The CTD(Comparative Toxicogenomics Database)database was used for GO and KEGG enrichment analysis of these target genes.Results:59 active ingredients that can be druggable were chosen from AM,67 active ingredients were chosen from AS.77 overlapping target genes for AM and ILD and 36 overlapping target genes for AS and ILD were acquired.The hub targets of AM were PTGS2,PTGS1,CDK2,MAOA,ESR1,TOP2A,GSK3B,ESR2,PPARG,NOS2,The hub targets of AS were PTGS2,GABRA1,PTGS1,CHRM1,SLC6A2,ADRA1B,ADRAIA,ADRB2,CHRM3,GABRA2,CHRM2.Quercetin,kaempferol,daidzein,pavilion,7-Hydroxycoumarin,and 5-Hydroxycoumarin were the main active ingredients which have more effective targets.Prediction of the protein-protein interaction network showed PTGS2,GSK3B,PPARG,etc.,were the important predicted targets.The enriched KEGG pathways,including the Immune System,Metabolism of lipids and lipoproteins,Cytokine Signaling in the Immune system,Generic Transcription Pathway,The interleukin pathway,Metabolism of proteins,PI3K-Akt signaling pathway,Metabolic pathways,Innate Immune System,Neuroactive ligand-receptor interaction,Metabolism,GPCR downstream signaling,Amine ligand-binding receptors,Class A/1,Calcium signaling pathway.Molecular docking showed that quercetin,kaempferol,daidzein,pavilion,7-Hydroxycoumarin,5-Hydroxycoumarin had good binding activities with PTGS2 and GSK3B,which mainly mediated PI3K/Akt and other important signaling pathways in the pathogenesis of ILD.Conclusion:The components in AS and AM share some common targets,such as PTGS2.AM and AS may ameliorate ILD through the PI3K-Akt signaling pathway which is mediated by GSK3B.PTGS2,PPARG may also be vital target genes in the treatment of ILD with AM and AS. 展开更多
关键词 Astragalus mongholicus Bunge Angelica sinensis Diels computational prediction interstitial lung disease PI3K-Akt signaling pathways
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宁夏河东沙地植被多样性与土壤的关系 被引量:2
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作者 王帅 马登科 +6 位作者 何志斌 孙玮皓 杜军 李睿 王文 杨淑萍 赵书玄 《中国沙漠》 CSCD 北大核心 2024年第4期202-211,共10页
明确植被多样性与土壤理化性质的关系是沙地植被保护和荒漠化治理的重要前提。本研究调查了宁夏河东沙地植被群落特征及土壤理化性质,探究了植被与土壤间的关系。结果表明:调查区域有植物15科、34属、41种,其中单种属29属,单属科11科。... 明确植被多样性与土壤理化性质的关系是沙地植被保护和荒漠化治理的重要前提。本研究调查了宁夏河东沙地植被群落特征及土壤理化性质,探究了植被与土壤间的关系。结果表明:调查区域有植物15科、34属、41种,其中单种属29属,单属科11科。草本植物占绝对优势,共计36种,占87.80%,仅5种灌木,无乔木。样地物种多样性指数(0.60~1.07)和均匀度指数(0.46~0.63)均较低,而优势度指数较高(0.46~0.68),植被组成较简单,群落优势种较突出。河东沙地主要为碱性土,部分区域为强碱性土,土壤未见明显盐化特征。有机质含量(1.68~2.80 g·kg^(-1))、全氮含量(0.12~0.20 g·kg^(-1))与科尔沁沙地和毛乌素沙地相当,但有效磷含量(0.41~1.85 mg·kg^(-1))仅为科尔沁沙地的20%,表明河东沙地植被可能存在磷限制现象。冗余分析表明,土壤指标能很好地解释河东沙地植被群落特征,第一排序轴的解释率达到75.87%,其中表层土壤全氮、有机质、C∶N总解释率达49.20%,表明表层土壤有机质和氮含量对河东沙地植被形成和分布有重要影响。河东沙地植被盖度与表层土壤水分含量极显著负相关、与土壤养分含量显著负相关,植被高度与表层土壤有机质和全氮含量显著负相关,物种丰富度和多样性指数与土壤养分间显著负相关。 展开更多
关键词 河东沙地 群落特征 多样性指数 土壤养分 冗余分析(RDA)
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Clinical and molecular significance of homologous recombination deficiency positive non-small cell lung cancer in Chinese population:An integrated genomic and transcriptional analysis 被引量:1
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作者 Yifei Wang Yidan Ma +14 位作者 Lei He jun du Xiaoguang Li Peng Jiao Xiaonan Wu Xiaomao Xu Wei Zhou Li Yang Jing Di Changbin Zhu Liming Xu Tianlin Sun Lin Li Dongge Liu Zheng Wang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2024年第3期282-297,共16页
Objective:The clinical significance of homologous recombination deficiency(HRD)in breast cancer,ovarian cancer,and prostate cancer has been established,but the value of HRD in non-small cell lung cancer(NSCLC)has not ... Objective:The clinical significance of homologous recombination deficiency(HRD)in breast cancer,ovarian cancer,and prostate cancer has been established,but the value of HRD in non-small cell lung cancer(NSCLC)has not been fully investigated.This study aimed to systematically analyze the HRD status of untreated NSCLC and its relationship with patient prognosis to further guide clinical care.Methods:A total of 355 treatment-naïve NSCLC patients were retrospectively enrolled.HRD status was assessed using the AmoyDx Genomic Scar Score(GSS),with a score of≥50 considered HRD-positive.Genomic,transcriptomic,tumor microenvironmental characteristics and prognosis between HRD-positive and HRDnegative patients were analyzed.Results:Of the patients,25.1%(89/355)were HRD-positive.Compared to HRD-negative patients,HRDpositive patients had more somatic pathogenic homologous recombination repair(HRR)mutations,higher tumor mutation burden(TMB)(P<0.001),and fewer driver gene mutations(P<0.001).Furthermore,HRD-positive NSCLC had more amplifications in PI3K pathway and cell cycle genes,MET and MYC in epidermal growth factor receptor(EGFR)/anaplastic lymphoma kinase(ALK)mutant NSCLC,and more PIK3CA and AURKA in EGFR/ALK wild-type NSCLC.HRD-positive NSCLC displayed higher tumor proliferation and immunosuppression activity.HRD-negative NSCLC showed activated signatures of major histocompatibility complex(MHC)-II,interferon(IFN)-γand effector memory CD8+T cells.HRD-positive patients had a worse prognosis and shorter progressionfree survival(PFS)to targeted therapy(first-and third-generation EGFR-TKIs)(P=0.042).Additionally,HRDpositive,EGFR/ALK wild-type patients showed a numerically lower response to platinum-free immunotherapy regimens.Conclusions:Unique genomic and transcriptional characteristics were found in HRD-positive NSCLC.Poor prognosis and poor response to EGFR-TKIs and immunotherapy were observed in HRD-positive NSCLC.This study highlights potential actionable alterations in HRD-positive NSCLC,suggesting possible combinational therapeutic strategies for these patients. 展开更多
关键词 Non-small cell lung cancer homologous recombination deficiency genetic alterations transcriptional analysis tumor microenvironment PROGNOSIS
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Coupling of BiOCl Ultrathin Nanosheets with Carbon Quantum Dots for Enhanced Photocatalytic Performance 被引量:1
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作者 Pin Song Xiaoyu Fang +14 位作者 Wei Jiang Yuyang Cao Daobin Liu Shiqiang Wei jun du Lang Sun Lei Zhao Song Liu Yuzhu Zhou jun Di Chade Lv Bijun Tang Jiefu Yang Tingting Kong Yujie Xiong 《Transactions of Tianjin University》 EI CAS 2024年第3期211-220,共10页
Over the past few decades,photocatalysis technology has received extensive attention because of its potential to mitigate or solve energy and environmental pollution problems.Designing novel materials with outstanding... Over the past few decades,photocatalysis technology has received extensive attention because of its potential to mitigate or solve energy and environmental pollution problems.Designing novel materials with outstanding photocatalytic activities has become a research hotspot in this field.In this study,we prepared a series of photocatalysts in which BiOCl nanosheets were modified with carbon quantum dots(CQDs)to form CQDs/BiOCl composites by using a simple solvothermal method.The photocatalytic performance of the resulting CQDs/BiOCl composite photocatalysts was assessed by rhodamine B and tetracycline degradation under visible-light irradiation.Compared with bare BiOCl,the photocatalytic activity of the CQDs/BiOCl composites was significantly enhanced,and the 5 wt%CQDs/BiOCl composite exhibited the highest photocatalytic activity with a degradation efficiency of 94.5%after 30 min of irradiation.Moreover,photocatalytic N_(2)reduction performance was significantly improved after introducing CQDs.The 5 wt%CQDs/BiOCl composite displayed the highest photocatalytic N_(2)reduction performance to yield NH_3(346.25μmol/(g h)),which is significantly higher than those of 3 wt%CQDs/BiOCl(256.04μmol/(g h)),7 wt%CQDs/BiOCl(254.07μmol/(g h)),and bare BiOCl(240.19μmol/(g h)).Our systematic characterizations revealed that the key role of CQDs in improving photocatalytic performance is due to their increased light harvesting capacity,remarkable electron transfer ability,and higher photocatalytic activity sites. 展开更多
关键词 Carbon quantum dots BiOCl Rhodamine B TETRACYCLINE PHOTOCATALYSIS
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内蒙古十大孔兑流域土地利用变化特征及驱动力 被引量:1
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作者 武娟娟 杜军 +6 位作者 旭日干 王文 苗晨鑫 任侠 杨志如 曹方圆 毛明月 《中国沙漠》 CSCD 北大核心 2024年第6期100-109,共10页
基于1990—2020年4期Landsat卫星30 m分辨率遥感影像,解译并获取了土地利用/覆被信息,采用动态变化率和土地利用转移矩阵方法,系统分析了十大孔兑流域在过去30年的土地利用时空变化规律,同时借助随机森林模型,对土地利用结构转变的驱动... 基于1990—2020年4期Landsat卫星30 m分辨率遥感影像,解译并获取了土地利用/覆被信息,采用动态变化率和土地利用转移矩阵方法,系统分析了十大孔兑流域在过去30年的土地利用时空变化规律,同时借助随机森林模型,对土地利用结构转变的驱动力进行了探究。结果表明:(1)研究时段内,林地持续扩大,沙地面积逐渐缩小,建设用地增加最显著(47.5%),其次为林地(36.8%),其余各组分结构均未发生剧烈变动;(2)土地利用类型间发生着频繁的属性转化,以耕地与草地的互转、草地与沙地向林地和建设用地的转化为主要特征;(3)相对于气候变化,人类活动在驱动流域土地利用结构转变进程中发挥着主导作用,突出地体现在林地的转入、草地和建设用地的转出及沙地的转化动态等方面。 展开更多
关键词 土地利用 时空特征 变化规律 驱动力 十大孔兑流域
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In-phase and out-of-phase spin pumping effects in Py/Ru/Pysynthetic antiferromagnetic structures
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作者 Zhaocong Huang Xuejian Tang +5 位作者 Qian Chen Wei Jiang Qingjie Guo Milad Jalali jun du Ya Zhai 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期541-545,共5页
The spin pumping effect in magnetic heterostructures and multilayers is a highly effective method for the generationand transmission of spin currents. In the increasingly prominent synthetic antiferromagnetic structur... The spin pumping effect in magnetic heterostructures and multilayers is a highly effective method for the generationand transmission of spin currents. In the increasingly prominent synthetic antiferromagnetic structures, the two ferromagneticlayers demonstrate in-phase and out-of-phase states, corresponding to acoustic and optical precession modes. Withinthis context, our study explores the spin pumping effect in Py/Ru/Py synthetic antiferromagnetic structures across differentmodes. The heightened magnetic damping resulting from the spin pumping effect in the in-phase state initially decreaseswith increasing Py thickness before stabilizing. Conversely, in the out-of-phase state, the amplified damping exceeds thatof the in-phase state, suggesting a greater spin relaxation within this configuration, which demonstrates sensitivity to alterationsin static exchange interactions. These findings contribute to advancing the application of synthetic antiferromagneticstructures in magnonic devices. 展开更多
关键词 spin pumping spin transmission synthetic antiferromagnetic structures spin dynamics
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Dielectric and energy storage properties of PbO–SrO–Nb_(2)O_(5)–Na_(2)O–Si thin films by annealing
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作者 Fei-Hu Tan Qing-Meng Zhang +3 位作者 Feng Wei Hong-Bin Zhao Xiao Zhang jun du 《Rare Metals》 SCIE EI CAS CSCD 2024年第1期351-355,共5页
Dielectric and energy storage properties of PbOSrO-Na_(2)O-Nb_(2)O_(5)-SiO_(2)(PSNNS) thin films with annealing temperature from 700 to 850 ℃ were investigated by measuring their capacitance-electric filed curve and ... Dielectric and energy storage properties of PbOSrO-Na_(2)O-Nb_(2)O_(5)-SiO_(2)(PSNNS) thin films with annealing temperature from 700 to 850 ℃ were investigated by measuring their capacitance-electric filed curve and hysteresis loops.The results show that the highest dielectric constant and energy density are 81.2 and 17.0 J·cm^(-3),respectively,which is obtained in the sample with annealing temperature of 800 ℃.Annealed from 700 to800 ℃,the dielectric constant and energy storage performance of PSNNS films are continuously improved.However,with annealing temperature up to 850 ℃,their dielectric constant decreases,which might be related with the removal of interfacial defects as a function of annealing temperature.Defect is one of the causes of space charge phenomenon,resulting in the increase in dielectric constant.Moreover,the micro structure analysis by X-ray diffraction(XRD) and transmission electron microscope(TEM) indicates that the change of crystallization phase and interfacial polarization takes responsibility to the results. 展开更多
关键词 Thin film Pulse laser deposition Annealing temperature Energy storage density
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