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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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Clinical and molecular significance of homologous recombination deficiency positive non-small cell lung cancer in Chinese population:An integrated genomic and transcriptional analysis
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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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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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Coupling of BiOCl Ultrathin Nanosheets with Carbon Quantum Dots for Enhanced Photocatalytic Performance
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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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Clinical value of oral contrast-enhanced ultrasonography in diagnosis of gastric tumors
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作者 Chuan-Yu Wang Xiao-Jing Fan +6 位作者 Fei-Liang Wang Yue-Yue Ge Zhao Cai Wei Wang Xin-Ping Zhou jun du De-Wei Dai 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第1期110-117,共8页
BACKGROUND The incidence of gastric cancer remains high,and it is the sixth most common cancer and the fourth leading cause of cancer deaths worldwide.Oral contrastenhanced ultrasonography is a simple,non-invasive,and... BACKGROUND The incidence of gastric cancer remains high,and it is the sixth most common cancer and the fourth leading cause of cancer deaths worldwide.Oral contrastenhanced ultrasonography is a simple,non-invasive,and painless method for the diagnosis of gastric tumors.AIM To explore the diagnostic value of oral contrast-enhanced ultrasonography for the detection of gastric tumors.METHODS The screening results based on oral contrast-enhanced ultrasonography and electronic gastroscopy were compared with those of the postoperative pathological examination.RESULTS Among 42 patients with gastric tumors enrolled in the study,the diagnostic accordance rate was 95.2%for oral contrast-enhanced ultrasonography(n=40)and 90.5%for electronic gastroscopy(n=38)compared with postoperative pathological examination.The Kappa value of consistency test with pathological findings was 0.812 for oral contrast-enhanced ultrasonography and 0.718 for electronic gastroscopy,and there was no significant difference between them(P=0.397).For the TNM staging of gastric tumors,the accuracy rate of oral contrast enhanced ultrasonography was 81.9%for the overall T staging and 50%,77.8%,100%,and 100%for T1,T2,T3,and T4 staging,respectively.The sensitivity and specificity were both 100%for stages T3 and T4.The diagnostic accuracy rate of oral contrast-enhanced ultrasonography was 93.8%,80%,100%,and 100%for stages N0,N1-N3,M0,and M1,respectively.CONCLUSION The accordance rate of qualitative diagnosis by oral contrast-enhanced ultrasonography is comparable to that of gastroscopy,and it could be used as the preferred method for the early screening of gastric tumors. 展开更多
关键词 Oral contrast-enhanced ultrasonography Gastric tumor Electronic gastroscopy Controlled study Pathological examination DIAGNOSIS
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Effect of power supply parameters on discharge characteristics and sterilization efficiency of magnetically driven rotating gliding arc
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作者 Shaohua QIN Meizhi WANG +2 位作者 jun du Lanlan NIE Jie PAN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第9期61-68,共8页
Plasma sterilization is a new generation of high-tech sterilization method that is fast,safe,and pollution free.It is widely used in medical,food,and environmental protection fields.Home air sterilization is an emergi... Plasma sterilization is a new generation of high-tech sterilization method that is fast,safe,and pollution free.It is widely used in medical,food,and environmental protection fields.Home air sterilization is an emerging field of plasma application,which puts higher requirements on the miniaturization,operational stability,and operating cost of plasma device.In this study,a novel magnetically driven rotating gliding arc(MDRGA)discharge device was used to sterilize Lactobacillus fermentation.Compared with the traditional gas-driven gliding arc,this device has a simple structure and a more stable gliding arc.Simulation using COMSOL Multiphysics showed that adding permanent magnets can form a stable magnetic field,which is conducive to the formation of gliding arcs.Experiments on the discharge performance,ozone concentration,and sterilization effect were conducted using different power supply parameters.The results revealed that the MDRGA process can be divided into three stages:starting,gliding,and extinguishing.Appropriate voltage was the key factor for stable arc gliding,and both high and low voltages were not conducive to stable arc gliding and ozone production.In this experimental setup,the sterilization effect was the best at 6.6 kV.A high modulation duty ratio was beneficial for achieving stable arc gliding.However,when the duty ratio exceeded a certain value,the improvement in the sterilization effect was slow.Therefore,considering the sterilization effect and energy factors comprehensively,we chose 80%as the optimal modulation duty ratio for this experimental device. 展开更多
关键词 PLASMA magnetically driven rotating gliding arc STERILIZATION
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Effect of Sr modification on microstructure and thermal conductivity of hypoeutectic Al−Si alloys 被引量:17
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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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基于多源资料的高原低涡源地研究 被引量:3
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作者 林志强 郭维栋 +3 位作者 姚秀萍 杜军 葛骏 周振波 《大气科学》 CSCD 北大核心 2023年第3期837-852,共16页
高原低涡是活跃于青藏高原近地面层的中尺度天气系统,是高原最重要的降水天气系统,少部分的低涡移出高原后在下游地区常带来灾害性的强降水天气。“青藏高原低涡切变线年鉴”(简称年鉴)是高原低涡研究的主要参考资料之一,但受到高原西... 高原低涡是活跃于青藏高原近地面层的中尺度天气系统,是高原最重要的降水天气系统,少部分的低涡移出高原后在下游地区常带来灾害性的强降水天气。“青藏高原低涡切变线年鉴”(简称年鉴)是高原低涡研究的主要参考资料之一,但受到高原西部地区探空观测站点分布不足的影响,年鉴难以监测发源于高原西部的低涡。为了进一步提高对高原低涡源地的科学认识,本研究首先分析了影响高原低涡发生发展的环流在高原东西部地区的差异,结果表明高原西部地区的环流背景更有利于高原低涡形成。再利用2005~2019年暖季(5~9月)风云-2地球静止卫星观测的云迹风和黑体亮温资料对年鉴低涡进行重分析,表明年鉴中大部分的高原低涡可以溯源至高原西部地区。最后分析了在高原西部的3个新探空站(狮泉河、改则和申扎)建立前后年鉴中高原低涡源地的差异,发现增加的探空资料使位于高原西部的低涡源地大幅度增加。综合多源资料的结果,我们认为大多数高原低涡起源于高原西部,年鉴的结论可能源于高原西部的探空站不足的影响。本研究确认了再分析资料在高原低涡研究中的可用性和有效性,强调了卫星观测资料在高原天气系统研究中的重要性和进一步增强高原地区气象观测的迫切性。 展开更多
关键词 高原低涡(TPV) 低涡源地 多源资料 高原低涡生成指数
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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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Effect of solute atom adsorption on heterogeneous nucleation by in-situ MgO particles:Experimental and theoretical studies
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作者 Liling Mo Hengbin Liao +2 位作者 Xiong Zhou Yu-jun Zhao jun du 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第10期3642-3656,共15页
The introduction of oxide inclusions during the smelting process has a clear promising heterogeneous nucleation potency on Mg-based alloys, but the mechanism has not been explored clearly yet. In the present work, the... The introduction of oxide inclusions during the smelting process has a clear promising heterogeneous nucleation potency on Mg-based alloys, but the mechanism has not been explored clearly yet. In the present work, the grain refinement mechanism of MgO in pure Mg,Mg-3Al and AZ31(Mg-2.9Al-0.9Zn-0.3Mn) alloys is investigated by combing first-principles calculations and experiments. The theoretical results show that solute atoms adsorption will affect the nucleation and the subsequent growth process, which is an important factor affecting the refinement efficiency. A contradiction between the experimental results and the grain growth restriction factor(GRF) theory is observed,that is the refinement ratio of AZ31 is worse than Mg-3Al alloy. This is explained by an adsorption model which reveals that Al promotes the adsorption of Mg on MgO surface so as to stimulate more particles available as nucleating sites. Meanwhile, Fe and Mn also have favorable effects on the adsorption of Mg, Zn may play the opposite role compared to Al. The theoretical analyzes provide a strong support to the experiments that Al benefits the initial nucleation of α-Mg on MgO to promote the grain refining effect of Mg-3Al prior to AZ31 alloy. 展开更多
关键词 Magnesium alloy First-principles calculation MGO Grain refinement ADSORPTION
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Thickness-dependent magnetic properties in Pt/[Co/Ni]_(n) multilayers with perpendicular magnetic anisotropy
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作者 晏春杰 陈丽娜 +9 位作者 周恺元 杨留鹏 付清为 王文强 岳文诚 梁力克 陶醉 杜军 王永磊 刘荣华 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期503-508,共6页
We systematically investigated the Ni and Co thickness-dependent perpendicular magnetic anisotropy(PMA)coefficient,magnetic domain structures,and magnetization dynamics of Pt(5 nm)/[Co(t_(Co))/Ni(t_(Ni))]_(5)/Pt(1 nm)... We systematically investigated the Ni and Co thickness-dependent perpendicular magnetic anisotropy(PMA)coefficient,magnetic domain structures,and magnetization dynamics of Pt(5 nm)/[Co(t_(Co))/Ni(t_(Ni))]_(5)/Pt(1 nm)multilayers by combining the four standard magnetic characterization techniques.The magnetic-related hysteresis loops obtained from the field-dependent magnetization M and anomalous Hall resistivity(AHR)ρxy showed that the two serial multilayers with t_(Co)=0.2 nm and 0.3 nm have the optimum PMA coefficient K_(U) as well as the highest coercivity H_(C) at the Ni thickness t_(Ni)=0.6 nm.Additionally,the magnetic domain structures obtained by magneto-optic Kerr effect(MOKE)microscopy also significantly depend on the thickness and K_(U) of the films.Furthermore,the thickness-dependent linewidth of ferromagnetic resonance is inversely proportional to K_(U) and H_(C),indicating that inhomogeneous magnetic properties dominate the linewidth.However,the intrinsic Gilbert damping constant determined by a linear fitting of the frequency-dependent linewidth does not depend on the Ni thickness and K_(U).Our results could help promote the PMA[Co/Ni]multilayer applications in various spintronic and spin-orbitronic devices. 展开更多
关键词 perpendicular magnetic anisotropy magnetic domain DAMPING multiayers
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Preliminary Evaluation of Hemodynamic Effects of Fontan Palliation on Renal Artery Using Computational Fluid Dynamics
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作者 Jinlong Liu Jing Shi +6 位作者 Weiru Luo Zhirong Tong Lefei Yang Peixuan Sun Tianyi Li jun du Qian Wang 《Congenital Heart Disease》 SCIE 2023年第1期41-55,共15页
Background:The assessment of renal function is important to the prognosis of patients needing Fontan palliation due to the reconstructed compromised circulation.To know the relationship between the kidney perfusion an... Background:The assessment of renal function is important to the prognosis of patients needing Fontan palliation due to the reconstructed compromised circulation.To know the relationship between the kidney perfusion and hemodynamic characteristics during surgical design could reduce the risk of acute kidney injury(AKI)and the postoperative complications.However,the issue is still unsolved because the current clinical evaluation methods are unable to predict the hemodynamic changes in renal artery(RA).Methods:We reconstructed a three-dimensional(3D)vascular model of a patient requiring Fontan palliation.The technique of computational fluid dynamics(CFD)was utilized to explore the changes of RA hemodynamics under different possible blood flow rates.The relationship between the kidney perfusion and hemodynamic characteristics was investigated.Results:The calculated results indicated the declined tendency of the pressure and pressure drop as the flow rate decreased.When the flow rate decreased to two-thirds of its baseline,both the pressure of left renal artery(LRA)and the pressure of right renal artery(RRA)dipped below 50%,and the pressure of RRA fell more quickly than that of LRA.Uneven distribution of WSS was observed on the trunk of RA,and the lowest WSS was found at the distal of RA.The average WSS in RA dropped to around 50%as the flow rate reached one-third of its baseline.Conclusions:As a promising approach,CFD can be utilized to quantitatively evaluate the hemodynamic characteristics of RA and contribute to offsetting the drawbacks of clinical assessments of renal function,to help realize better prognosis for the patients with Fontan palliation. 展开更多
关键词 Renal artery Fontan palliation HEMODYNAMICS computational fluid dynamics surgical design
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术前全身炎症反应指数对中高危非肌层浸润性膀胱癌预后的影响
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作者 杜君 段鹏强 +1 位作者 张超 姚欣 《中国肿瘤临床》 CAS CSCD 北大核心 2023年第16期829-833,共5页
目的:探讨术前全身炎症反应指数(systemic inflammatory response index,SIRI)对中高危非肌层浸润性膀胱癌(nonmuscle invasive bladder cancer,NMIBC)预后的影响。方法:回顾性分析2013年1月至2015年7月于天津医科大学肿瘤医院行经尿道... 目的:探讨术前全身炎症反应指数(systemic inflammatory response index,SIRI)对中高危非肌层浸润性膀胱癌(nonmuscle invasive bladder cancer,NMIBC)预后的影响。方法:回顾性分析2013年1月至2015年7月于天津医科大学肿瘤医院行经尿道膀胱肿瘤电切术(transurethral resection of bladder tumor,TURBT)治疗的103例NMIBC患者的临床资料,根据术后患者有无复发或进展分为复发组和未复发组以及进展组和未进展组。根据组间比较结果,绘制SIRI的受试者工作特征曲线(receiver operating characteristic curve,ROC),求得最优截断值对患者进行分组。通过Kaplan-Meier法和Cox单因素及多因素分析确定影响NMIBC患者预后的危险因素。结果:SIRI值在复发患者和未复发患者间差异无统计学意义(P=0.393);患者的年龄(P=0.016)、性别(P=0.030)、肿瘤数目(P=0.008)、分期(P<0.001)、分级(P<0.001)、是否初发(P=0.002)、单核细胞计数(P=0.042)以及SIRI(P=0.044)差异具有统计学意义;根据ROC曲线确定SIRI鉴定患者术后是否出现进展的最佳临界值,将患者分为低SIRI组和高SIRI组,生存分析对比两组间的无进展生存期(progression-free survival,PFS)差异具有统计学意义(P=0.005)。Cox多因素分析结果显示,肿瘤数目(P=0.041)、是否初发(P=0.041)及SIRI≥0.725(P=0.025)是NMIBC患者TURBT术后PFS的独立预后因素。结论:SIRI是影响中高危NMIBC患者进展的独立危险因素,术前SIRI对预测肿瘤分期有一定的应用价值。 展开更多
关键词 非肌层浸润性膀胱癌 全身炎症反应指数 肌层浸润性膀胱癌 预后
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