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| 1 | Solar activity effects of the ionosphere: A brief review显示文摘Solar radiation, which varies over multiple temporal scales, modulates remarkably the evolution of the ionosphere. The solar activity dependence of the ionosphere is a key and fundamental issue in ionospheric physics, providing information essential to understanding the variations in the ionosphere and its processes. Selected recent studies on solar activity effects of the ionosphere are briefly reviewed in this report. This report focuses on (1) observations of solar irradiance at X-ray and extreme ultraviolet wavelengths and the outstanding problems of solar proxies, in the view of ionospheric studies, (2) new findings and improved representations of the features of the solar activity dependence of ionospheric key parameters and the corresponding physical processes, (3) possible phenomena in the ionosphere under extremely high and low solar activity conditions that are unique, as indicated by historical solar datasets and the deep solar minimum of solar cycle 23/24, and (4) statistical studies and model simulations of the ionosphere response to solar flares. The above-mentioned studies provide new clues for comprehensively explaining basic processes in the ionosphere and improving the prediction capability of ionospheric models and related applications. | LIU LiBo WAN WeiXing CHEN YiDing LE HuiJun | 2011 | Chinese Science Bulletin2011，56，12： | 45 |
| 2 | Image segmentation of embryonic plant cell using pulse-coupled neural networks显示文摘Traditional image segmentation algorithms exhibit weak performance for plant cells which have complex structure. On the other hand, pulse-coupled neural network (PCNN) based on Eckhorn’s model of the cat visual cortex should be suitable to the segmentation of plant cell image. But the present theories cannot explain the relationship between the parameters of PCNN mathematical model and the effect of segmentation. Satisfactory results usually require time-consuming selection of experimental parameters. Mean-while, in a proper, selected parametric model, the number of iteration determines the segmented effect evaluated by visual judgment, which decreases the efficiency of image segmentation. To avoid these flaws, this note proposes a new PCNN algorithm for automatically segmenting plant embryonic cell image based on the maximum entropy principle. The algorithm produces a desirable result. In addition, a model with proper parameters can automatically determine the number of iteration, avoid visual judgment, | MA Yide DAI Rolan LI Lian WEI Lin | 2002 | Chinese Science Bulletin2002，47，2： | 28 |
| 3 | Methylation and mutation analysis of p16 gene in gastric cancer显示文摘AIM: To study methylation, frequencies of homozygous deletion and mutation of p16 gene in gastric carcinoma.METHODS: The methylation pattern in exon 1 and exon 2of p16 gene was studied with polymerase chain reaction (PCR), using methylation sensitive restriction endonuclease HpaⅡ and methylation insensitive restriction endonudease MspⅠ. PCR technique was used to detect homozygous deletions of exon 1 and exon 2 of p16 gene and single strand conformation polymorphism (SSCP) technique was used to detect the mutation of the gene.RESULTS: Hypermethylation changes in exon 1 and exon 2 of p16 gene were observed in 25 % and 45 % of 20gastric cancer tissues, respectively, while no methylation abnormality was found in normal tissues. The homozygous deletion frequency of exon 1 and exon 2 of p16 gene in 20gastric cancer tissues was 20 % and 10 %, respectively. No mutation was found in exon 1 of p16 gene, while abnormal single strands were found in 2 (10 %) cases in exon 2 as detected by SSCP.CONCLUSION: The results suggest that hypermethylation and abnormality of p16 gene may play a key role in the progress of gastric cancer. Hypermethylation of exon 2 of p16 gene may have effects on the carcinogenesis of gastric mucosa and may be a later event. | YiDing Xiao-PingLe Qin-XianZhang PengDu | 2003 | World Journal of Gastroenterology2003，9，3： | 21 |
| 4 | PCNN Model Analysis and Its Automatic Parameters Determination in Image Segmentation and Edge Detection显示文摘The Pulse coupled neural network(PCNN)has been widely used in digital image processing, but the automatic parameters determination is still a difficult aspect, which becomes the focus of PCNN research. In this paper, by the classical solution to difference equations and the time-domain analysis of PCNN model, we provide the expressions of the firing time and the firing period of neurons, and reveal the 'mathematics firing' phenomenon of PCNN. Based on this, we propose a new method of automatic parameters determination based on both eliminating the 'mathematics firing' and getting the highest efficiency of PCNN. We also present an edge detection model on the basis of image segmentation of PCNN and a method to determine automatically the parameters of the model. Experimental results prove the validity and efficiency of our proposed algorithm for the segmentation and the edge detection of the test images. | DENG Xiangyu MA Yide | 2014 | Chinese Journal of Electronics2014，23，1： | 20 |
| 5 | Community Characteristics of Early Recovery Vegetation on Abandoned Lands of Shifting Cultivation in Bawangling of Hainan Island, South China显示文摘Shifting cultivation is a major form of agricultural practice in most parts of tropical regions worldwide. In places where the bush fallow period is excessively shortened or the period of cultivation is extended for too long, the rate of vegetation recovery and biodiversity on abandoned lands of shifting cultivation would decline. The recovery of the secondary plant communities could even be inhibited for a prolonged period because of grass occupancy. Because of the vital significance of the early recovery communities to secondary succession, we studied the community characteristics of early recovery vegetation on abandoned lands of shifting cultivation in Bawangling of Hainan Island. Measurements were made of the community composition and structure of early recovery vegetation. The sprouting abilities of different functional groups and different species in the same functional group, and the effect of the grass functional group on the composition and quantitative characteristics of tree and shrub functional groups were analyzed. Results indicated that only a few families, genera, or species apparently dominated in the early recovery vegetation on the abandoned lands of shifting cultivation and that deciduous species occurred with a rather high percentage in this early recovery community compared with the natural secondary or old growth forests. Smallsized individuals dominated the woody community. The abundance and basal area of sprouting stems for species in the tree functional group were greater than those of seeder stems, whereas the abundance and basal area of resprouters and seeders for species in the shrub functional group did not differ. The total abundance of stems for the community, stem abundances for species in tree or shrub functional groups, and for seeder or resprouter stems were all negatively correlated with coverage of the grass functional group. The mean sprouting ability in the tree functional group was greater than in the shrub functional group. The sprouting ability for different species in the same functional group was also significantly different. | YiDING Run-GuoZANG | 2005 | Journal of Integrative Plant Biology2005，47，5： | 16 |
| 6 | Inhibition of the STAT3 signaling pathway is involved in the antitumor activity of cepharanthine in SaOS2 cells显示文摘瞄准: 调查位于 cepharanthine (CEP ) 的 antitumor 活动下面的分子的机制,从 Stephania cepharantha Hayata 提取的碱。 | ZanChen ChenHuang Yan-lingYang YiDing Han-qiangOu-Yang You-yiZhang MingXu | 2012 | Acta Pharmacologica Sinica2012，33，1： | 14 |
| 7 | Genetic pattern of belt-wide petroliferous phenomenon in the eastern Pearl River Mouth Basin and its practical application显示文摘The Pearl River Mouth Basin(PRMB) covers an area of approximately 20×104 km2. However, oil-gas fields detected in this area thus far are highly concentrated and controlled predominantly by second-order structural belts, the seven largest of which aggregate proved oil reserves of 7.7×108 m3, accounting for 86% of the total discovered reserve in the basin. These second-order structures have one common phenomenon: oil is contained in all traps present in them. In other words, they are all belt-wide petroliferous reservoirs. Research has identified eight types of second-order structural belts under two categories in the eastern PRMB. Their petroliferous properties are subject to three typical constraints: petroliferous properties of subsags hosting these structural belts, locations of these belts in the petroleum system, and availability of traps prior to the hydrocarbon expulsion and migration. The formation and distribution of oil reservoirs in these belts are characterized by subsag–belt integration and 'three-in-one'. The former indicates that sags and the second-order structural belts within the supply range of the sags constitute the basic units of hydrocarbon accumulations and are therefore inseparable. The latter indicates that a belt-wide petroliferous second-order structural belt always contains three important elements: hydrocarbon richness, effective pathway and pre-existing traps. | Shi Hesheng Dai Yiding Liu Lihua Shu Yu Mei Lianfu | 2014 | Petroleum Science2014，11，1： | 14 |
| 8 | Dipeptidyl peptidase Ⅳ(DPP Ⅳ):a novel emerging target for thetreatment of type 2 diabetes显示文摘The enzyme, dipeptidyl peptidase Ⅳ(DPP Ⅳ), is a novel target for the treatment of type 2 diabetes. Dipeptidyl peptidase Ⅳ inhibition improves the impaired insulin secretion and decrease postprandial concentrations of glucagon by enhancing the incretin hormone levels lucagon-like peptide-1(GLP-1) and glucose-dependent insulinotropic polypeptide/gastric inhibitory polypeptide(GIP). Recently, DPP Ⅳ inhibitors have attracted more and more attention, several of which have entered pre-clinical and clinical trials, and one has received approval for use as an anti-diabetic agent. Among the DPP Ⅳ inhibitors, two leading agents(sitagliptin and vildagliptin) have been shown to be effective in reducing glycosylated hemoglobin(HbA1c) and fasting plasma glucose(FPG) in patients with type 2 diabetes. This review summarizes the evidence supporting DPP IV inhibitors as potential antidiabetic agents. | Jing Wu Yiding Chen Xiaoli Shi Wei Gu | 2009 | Journal of Nanjing Medical University2009，23，4： | 9 |
| 9 | Temperature and substrate availability regulate soil respiration in the tropical mountain rainforests,Hainan Island,China显示文摘Aims Tropical forest plays a key role in global C cycle;however,there are few studies on the C budget in the tropical rainforests in Asia.This study aims to(i)reveal the seasonal patterns of total soil respiration(R_(T)),litter respiration(R_(L))and soil respiration without surface organic litter(R_(NL))in the primary and secondary Asian tropical mountain rainforests and(ii)quantify the effects of soil temperature,soil moisture and substrate availability on soil respiration.Methods The seasonal dynamics of soil CO_(2) efflux was measured by an automatic chamber system(Li-8100),within the primary and secondary tropical mountain rainforests located at the Jianfengling National Reserve in Hainan Island,China.The litter removal treatment was used to assess the contribution of litter to belowground CO_(2) production.Important Findings The annual R_(T) was higher in the primary forest(16.73±0.87 Mg C ha−1)than in the secondary forest(15.10±0.26 Mg C ha−1).The rates of R_(T),R_(NL) and R_(L) were all significantly higher in the hot and wet season(May–October)than those in the cool and dry season(November–April).Soil temperature at 5cm depth could explain 55–61%of the seasonal variation in R_(T),and the temperature sensitivity index(Q_(10))ranked by R_(L)(Q_(10)=3.39)>R_(T)(2.17)>R_(NL)(1.76)in the primary forest and by R_(L)(4.31)>R_(T)(1.86)>R_(NL)(1.58)in the secondary forest.The contribution of R_(L) to R_(T) was 22–23%,while litter input and R_(T) had 1 month time lag.In addition,the seasonal variation of R_(T) was mainly determined by soil temperature and substrate availability.Our findings suggested that global warming and increased substrate availability are likely to cause considerable losses of soil C in the tropical forests. | Zhang Zhou Lai Jiang Enzai Du Huifeng Hu Yide Li Dexiang Chen Jingyun Fang | 2013 | Journal of Plant Ecology2013，6，5： | 8 |
| 10 | Circulating tumor cells:biology and clinical significance显示文摘Circulating tumor cells(CTCs)are tumor cells that have sloughed off the primary tumor and extravasate into and circulate in the blood.Understanding of the metastatic cascade of CTCs has tremendous potential for the identification of targets against cancer metastasis.Detecting these very rare CTCs among the massive blood cells is challenging.However,emerging technologies for CTCs detection have profoundly contributed to deepening investigation into the biology of CTCs and have facilitated their clinical application.Current technologies for the detection of CTCs are summarized herein,together with their advantages and disadvantages.The detection of CTCs is usually dependent on molecular markers,with the epithelial cell adhesion molecule being the most widely used,although molecular markers vary between different types of cancer.Properties associated with epithelial-tomesenchymal transition and stemness have been identified in CTCs,indicating their increased metastatic capacity.Only a small proportion of CTCs can survive and eventually initiate metastases,suggesting that an interaction and modulation between CTCs and the hostile blood microenvironment is essential for CTC metastasis.Single-cell sequencing of CTCs has been extensively investigated,and has enabled researchers to reveal the genome and transcriptome of CTCs.Herein,we also review the clinical applications of CTCs,especially for monitoring response to cancer treatment and in evaluating prognosis.Hence,CTCs have and will continue to contribute to providing significant insights into metastatic processes and will open new avenues for useful clinical applications. | Danfeng Lin Lesang Shen Meng Luo Kun Zhang Jinfan Li Qi Yang Fangfang Zhu Dan Zhou Shu Zheng Yiding Chen Jiaojiao Zhou | 2021 | Signal Transduction and Targeted Therapy2021，6，12： | 8 |
| 11 | Development of a middle and low latitude theoretical ionospheric model and an observation system data assimilation experiment显示文摘On the basis of previous work, we develop a middle and low latitude theoretical ionospheric model in this paper, named Theoretical Ionospheric Model of the Earth in the Institute of Geology and Geophysics, Chinese Academy of Sciences (TIME-IGGCAS). TIME-IGGCAS solves the equations of mass continuity, motion and energy of electron and ions self-consistently and uses an eccentric dipole field approxima-tion to the Earth’s magnetic field. We combine the Eulerian and Lagrangian approaches in the model and take account of the plasma E×B drift velocity. Calculation results reveal that the model is steady and credible and can reproduce most large-scale features of ionosphere. By using TIME-IGGCAS, we carried out an observation system data assimilation experiment. Assimilation results show that the E×B drift velocity can be accurately estimated by ingesting the observed foF2 and hmF2 into the model ap-plying nonlinear least-square fit method. We suggest that this work is of great significance in the de-velopment of ionospheric data assimilation model to give better nowcast and forecast of ionosphere. | YUE XinAn WAN WeiXing LIU LiBo LE HuiJun CHEN YiDing YU Tao | 2008 | Chinese Science Bulletin2008，53，1： | 7 |
| 12 | Comparison of nuclear matrix proteins between gastric cancer and normal gastric tissue显示文摘AIM: To study the alteration of nuclear matrix proteins (NMPs) in gastric cancer. METHODS: The NMPs extracted from 22 cases of gastric cancer and normal gastric tissues were investigated by SDS-PAGE technique and the data were analyzed using Genetools analysis software. RESULTS: Compared with normal gastric tissue, the expression of 30 ku and 28 ku NMPs in gastric cancer decreased significantly (P=-0.002, P=0.001, P<0.05). No significant difference was found in the expression of the two NMPs between the various differentiated grades (P=0.947, P=-0.356) and clinical stages of gastric cancer (P=0.920, P=-0.243, P>0.05). CONCLUSION: The results suggested that the alteration of NMPs in gastric cancer occurred at the early stage of gastric cancer development. | Qin-XianZhang YiDing ZhuoLi Xiao-PingLe WeiZhang LingSun Hui-RongShi | 2004 | World Journal of Gastroenterology2004，10，12： | 7 |
| 13 | CO_2选择性氧化甲烷制C_2烃催化剂La_2O_3/ZnO的氧化还原和CO_2吸附性能显示文摘La2O3/ZnO催化剂体系在以二氧化碳作为氧化剂的甲烷氧化偶联反应中具有很高的C2烃选择性和稳定性.采用CO2-TPD-MS和TPR技术考察了La2O3/ZnO对CO2的吸附性质及其氧化还原行为.结果表明:(1)La2O3/ZnO催化剂体系存在着强、弱两种碱中心,其中弱碱中心数量随样品中La2O3含量增加而减少,强碱中心强度随样品中La2O3含量增加而增强.(2)由于组分相互作用,高温下,La2O3/ZnO易产生晶格氧空位,使之对CO2的吸附增强,吸附后的CO2与晶格氧作用形成立方晶型La2O2CO3.(3)La2O3/ZnO表面的La3+和Zn2+可以部分被还原,由于组分间的相互作用,使得二者的还原都较单一组分存在时更难.(4)H2-CO2-H2氧化还原循环实验表明,La2O3/ZnO表面被部分还原后,CO2可以将部分被还原的表面再氧化.在此基础上对La2O3/ZnO催化剂上甲烷与CO2转化为C2烃的机制也进行了讨论. | Chen Changlin, Xu Yide, Cui Wei, Cai Yuran (State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, The Chinese Academy of Sciences, Dalian 116023) | 1998 | 催化学报1998，19，3： | 7 |
| 14 | 解析胃癌前病变及早期胃癌的单细胞转录组网络显示文摘文章简介本研究采集了一组处于胃癌前病变不同阶段及早期胃癌患者,这些患者还具有胃灼痛、大便干燥、舌苔黄或厚等若干中医'胃火'相关临床表现。通过解析单细胞网络,研究发现高表达MUC6的腺粘膜细胞随着疾病的进展出现了肠样干细胞表型,提示其可能是介导肿瘤发生的关键步骤。 | 张鹏 Mingran Yang Yiding Zhang Shuai Xiao Xinxing Lai Aidi Tan Shiyu Du 李梢 | 2020 | 科学新闻2020，，2： | 7 |
| 15 | Studies on microsatellite instability in p16 gene and expression of hMSH2 mRNA in human gastric cancer tissues显示文摘AIM: To detect the loss of heterozygosity (LOH) frequency of microsatellite sites D9s171, D9s1604 of p16 gene and expression of hMSH2 mRNA in various differentiated types of gastric cancer, adjacent cancer tissues and normal gastric mucosa.METHODS: LOH was detected by polymerase chain reaction (PCR)-denaturing polyacrylamide gel electrophoresis-silver staining. The expression of hMSH2 mRNA was examined with in situ hybridization.RESULTS: The frequency rate of LOH was significantly higher in gastric cancers than that in adjacent cancer tissues (P=0.032). No significant difference was noted among various differentiated types and various clinical stages of gastric cancers. The significantly reduced expression of hMSH2mRNA positive signal cells exhibited in gastric cancers, in comparison with that in the adjacent cancer tissues and normal gastric mucosa, respectively (P=0.001). No significant difference was noted among various clinical stages of gastric cancers (P>0.05). The difference of positive signal cells in poorly differentiated cancers and those in well and moderately differentiated cancers were significant (P<0.001).CONCLUSION: The frequencies of LOH in two microsatellite sites, D9s171 and D9s1604, in p16 genome were associated with development of gastric cancer and no significant correlation was demonstrated between the LOH frequency and the cell differentiated types of tumor cells or clinical stages. There was a positive relationship between the expression of hMSH2 mRNA and the differentiated types of gastric cancer. | Qin-XianZhang YiDing Xiao-PingLe PengDu | 2003 | World Journal of Gastroenterology2003，9，3： | 6 |
| 16 | Facile grafting strategy synthesis of single-atom electrocatalyst with enhanced ORR performance显示文摘Single-atom catalysts(SACs)have become one of the most considered research directions today,owing to their maximum atom utilization and simple structures,to investigate structure-activity relationships.In the field of non-precious-metal electrocatalysts,atomically dispersed Fe-N4 active sites have been proven to possess the best oxygen reduction activity.Yet the majority of preparation methods remains complex and costly with unsatisfying controllability.Herein,we have designed a surface-grafting strategy to directly synthesize an atomically dispersed Fe-NVC electrocatalyst applied to the oxygen reduction reaction(ORR).Through an esterification process in organic solution,metal-containing precursors were anchored on the surface of carbon substrates.The covalent bonding effect could suppress the formation of aggregated particles during heat treatment.Melamine was further introduced as both a cost-effective nitrogen resource and blocking agent retarding the migration of metal atoms.The optimized catalyst has proven to have abundant atomically dispersed Fe-N4 active sites with enhanced ORR catalytic performance in acid condition.This method has provided new feasible ideas for the synthesis of SACs. | Rui Ding Yide Liu Zhiyan Rui Jia Li Jianguo Liu Zhigang Zou | 2020 | Nano Research2020，13，6： | 6 |
| 17 | miRNA-181 regulates embryo implantation in mice through targeting leukemia inhibitory factor显示文摘Embryo implantation is a crucial step in mammalian reproduction.However,little is known regarding the physiological roles of microRNAs in the regulation of embryo implantation.Here we show that a minimum uterine expression of miR-181 is essential for the onset of embryo implantation.Both transient and prolonged transgenic expression of miR-181 led to impaired implantation,which can be rescued by exogenous administration of leukemia inhibitory factor(LIF).Mechanistically,miR-181 is able to directly target LIF and downregulate LIF expression,thereby inhibiting embryo implantation.We also show that miR-181 expression is regu-lated by the transcriptional factor Emx2,and the Emx2–miR-181 axis plays an importantrole in regulating embryo implantation.Taken together,these results reveal a novel function of miR-181 in embryo implantation through the regulation of LIF,and also indicate a potential link between miR-181 dysregulation and human embryo implantation defects. | Bo Chu Liangwen Zhong Shuang Dou Jun Wang Jianmin Li Mingwei Wang Qinghua Shi Yide Mei Mian Wu | 2015 | Journal of Molecular Cell Biology2015，7，1： | 5 |
| 18 | Transportation characteristics of gas-solid two-phase flow in a long-distance pipeline显示文摘In this study,experiments on fly ash conveying were carried out with a home-made long-distance positive-pressure pneumatic conveying system equipped with a high performance electrical capacitance tomography system to observe the transient characteristics of gas-solid two-phase flow.The experimental results indicated that sol ids throughput increased with increasing solids-gas ratio when the conveying pipeline was not plugged.Moreover,the optimum operating state was determined for the 1000 m long conveying pipeline with a throttle plate of 26 orifices.At this state the solids throughput was about 12.97 t/h.Additionally,the transportation pattern of fly ash gradually changed from sparse-dense flow to partial and plug flows with increasing conveying distance because of the conveying pressure loss.These experimental results provide important reference data for the development of pneumatic conveying technology. | Xiaoqiang Zhang Dongfeng Zhang An Wang Yide Geng | 2015 | Particuology2015，13，4： | 5 |
| 19 | Effect of addition of Al-Si eutectic alloy on microstructure and mechanical properties of Mg-12wt%Li alloy显示文摘Mg-12 Li, Mg-12 Li-3(Al-Si), Mg-12 Li-7(Al-Si) and Mg-12 Li-9(Al-Si) alloys(all in wt%) were fabricated by high frequency vacuum induction melting in a water cooled copper crucible. After subsequently hotrolling and annealing, their microstructure and mechanical properties were investigated. Experimental results show that mechanical properties of Mg-12 Li alloy were significantly improved by the addition of Al-Si eutectic alloy. Mg-12 Li-7(Al-Si) alloy shows the highest strength of 196 MPa of the investigated alloys, which is about 1.8 times of the strength of Mg-12 Li alloy, and maintains high elongation of 27%.The improved mechanical property with addition of Al and Si in the eutectic proportion into Mg-12 Li alloy was attributed to the solution strengthening effect of A1 and precipitation hardening effect from AlLi and Mg_2 Si precipitates. | Zilong Zhao Xuegang Xing Jinyu Ma Liping Bian Wei Liang Yide Wang | 2018 | Journal of Materials Science & Technology2018，34，9： | 5 |
| 20 | Effect of pre-homogenizing treatment on microstructure and mechanical properties of hot-rolled AZ91 magnesium alloys显示文摘To improve the homogeneity and rolling formability of as-cast AZ91 magnesium,the effects of pre-homogenizing treatment on microstructure evolution,deformation mechanism,mechanical properties and tensile fracture morphology of hot-rolled AZ91 magnesium alloy were studied.The results showed that the amount of coarseβ-Mg17Al12 phase decreases dramatically,being distributed along the grain boundaries as small strips after homogenizing.Twining plays a dominant role in the deformation mechanism of AZ91 alloys in the experimental condition,while dynamic recrystallization(DRX)considerably occurred in homogenized-rolled alloys,contributed to microstructure uniformity andβ-Mg17Al12 phase precipitated refinement.The tensile strength of homogenized-rolled AZ91 alloys increases dramatically with elongation declining slightly in contrast to homogenized alloys.The fracture surface of homogenized-rolled specimen exhibits more ductile fracture with the manifestation of a large amount of dimples distributing higher density in matrix,while the micro cracks are prone to initiate around the Mg/Mg17Al12 phase interface and grain boundaries owing to the fragile interface bonding of two phases. | Liuwei Zheng Huihui Nie Wei Liang Hongxia Wang Yide Wang | 2016 | Journal of Magnesium and Alloys2016，4，2： | 5 |
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