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| 1 | A Highly Pathogenic Strain of Porcine Deltacoronavirus Caused Watery Diarrhea in Newborn Piglets显示文摘Porcine deltacoronavirus(PDCoV) is a newly identified virus that causes watery diarrhea in newborn piglets and results in significant economic losses to the pig industry. Since first reported in Hong Kong in 2012, PDCoV has been subsequently detected in USA, South Korea, Thailand, and China's Mainland. Here we isolated a strain of PDCoV, named CHN-GD-2016,from the intestinal content of a diseased newborn piglet with severe diarrhea in a pig farm in Guangdong, China. PDCoV CHN-GD-2016 could be identified by immunofluorescence with PDCoV specific rabbit antisera, and typical crown-shaped particles with spiky surface projections of this PDCoV were observed with electron microscopy. Genomic analysis showed that the PDCoV CHN-GD-2016 was closely related to other Chinese PDCoV strains, with the highest sequence similarity with the strain CHN/Tianjin/2016. Importantly, inoculation of newborn piglets with 1×10~5 TCID_(50) of CHN-GD-2016 by oral feeding successfully reproduced clear clinical symptoms, including vomiting, dehydration, and severe diarrhea in piglets. In addition, the virus RNA in rectal swabs from 1 to 7 days post inoculation was detected, macroscopic and microscopic lesions in small intestine were observed, and viral antigen was also detected in the small intestines with immunohistochemical staining. Collectively, the data show in this study confirms that PDCoV is present in Guangdong,China and is highly pathogenic in newborn piglets. | Zhichao Xu Huiling Zhong Qingfeng Zhou Yunping Du Li Chen Yun Zhang Chunyi Xue Yongchang Cao | 2018 | Virologica Sinica2018,33,2: | 16 |
| 2 | Environmental changes during early-middle Holocene from the sediment record of the Chaohu Lake,Anhui Province显示文摘A typical lake sediment core is obtained from the Chaohu Lake in the lower reaches of the Yangtze River,Anhui Province,China.The timing scale is constrained by AMS 14 C dating method.Climate proxies such as pollen and grain size in the core are analyzed to reconstruct the environment changes at this site approximately between 9870 and 2170 cal.a BP.The results indicate that at the research area, the climate in the early-middle Holocene had evolved through 3 stages.From 9870 to 6040 cal.a BP, proxy records show a warm and dry climate with low water levels after the late-glacial period.During this stage,cool and dry events occurred at about 8910 and 6060-6030 cal.a BP.Then,between 6040 and 4860 cal.a BP,the climate was humid and vegetation was more flourishing in the Chaohu Lake Valley.The Holocene Optimum occurred at 5840-5500 cal.a BP in the Chaohu Lake,showing the best condition of water and heat.Elm Decline occurred at the period of 5380-4930 cal.a BP.Since 4860 cal.a BP,the climate was warm and dry through 2170 cal.a BP as shown in both pollen spectrum and grain-size histories.Two obvious dry events occurred in 3760 and 2170 cal.a BP,respectively.At 2170 cal.a BP,the water level of the Chaohu Lake reached the lowest as the lakebed possibly exposed. Such lake sediment observations are consistent with the historical records in this area. | XinYuan Wang GuangSheng Zhang Li Wu XiHui Zhang EnLou Zhang XiaYun Xiao QingFeng Jiang | 2008 | Chinese Science Bulletin2008,53,S1: | 15 |
| 3 | Effect of sintering temperature in argon atmosphere on microstructure and properties of 3D printed alumina ceramic cores显示文摘Alumina ceramics with different sintering temperatures in argon atmosphere were obtained using stereolithography-based 3D printing.The effects of sintering temperature on microstructure and physical and mechanical properties were investigated.The results show that the average particle size,shrinkage,bulk density,crystallite size,flexural strength,Vickers hardness,and nanoindentation hardness increased with the increase in sintering temperature,whereas the open porosity decreased with increasing sintering temperature.No change was observed in phase composition,chemical bond,atomic ratio,and surface roughness.For the sintered samples,the shrinkage in Z direction is much greater than that in X or Y direction.The optimum sintering temperature in argon atmosphere is 1350℃with a shrinkage of 3.0%,3.2%,and 5.5%in X,Y,and Z directions,respectively,flexural strength of 26.7 MPa,Vickers hardness of 198.5 HV,nanoindentation hardness of 33.1 GPa,bulk density of 2.5 g/cm^3,and open porosity of 33.8%.The optimum sintering temperature was 70℃higher than that sintering in air atmosphere when achieved the similar properties. | He LI Yongsheng LIU Yansong LIU Qingfeng ZENG Kehui HU Zhigang LU Jingjing LIANG | 2020 | Journal of Advanced Ceramics2020,9,2: | 13 |
| 4 | A group of SUVH methyl-DNA binding proteins regulate expression of the DNA demethylase ROS_1 in Arabidopsis显示文摘DNA methylation is typically regarded as a repressive epigenetic marker for gene expression.Genome-wide DNA methylation patterns in plants are dynamically regulated by the opposing activities of DNA methylation and demethylation reactions. In Arabidopsis, a DNA methylation monitoring sequence(MEMS) in the promoter of the DNA demethylase gene ROS_1 functions as a methylstat that senses these opposing activities and regulates genome DNA methylation levels by adjusting ROS_1 expression. How DNA methylation in the MEMS region promotes ROS_1 expression is not known. Here, we show that several Su(var)3-9 homologs(SUVHs) can sense DNA methylation levels at the MEMS region and function redundantly to promote ROS_1 expression. The SUVHs bind to the MEMS region, and the extent of binding is correlated with the methylation level of the MEMS.Mutations in the SUVHs lead to decreased ROS_1 expression, causing DNA hypermethylation at more than 1,000 genomic regions. Thus, the SUVHs function to mediate the activation of gene transcription by DNA methylation. | Xinlong Xiao Jieqiong Zhang Tao Li Xing Fu Viswanathan Satheesh Qingfeng Niu Zhaobo Lang Jian-Kang Zhu Mingguang Lei | 2019 | Journal of Integrative Plant Biology2019,61,2: | 11 |
| 5 | Deformation mechanism and microstructures on polycrystalline aluminum induced by high-current pulsed electron beam显示文摘In this paper, we present an experimental investigation of deformation twinning in polycrystalline aluminum exposed to high-current pulsed electron beam (HCPEB) irradiation. The residual tensile stress with about 10 2 MPa was introduced in the irradiated surface layer. The feature characteristic irradiated with various numbers of pulses was investigated. The formation of a large number of twin bands on the surface irradiated with multiple pulses was determined. The experimental observations indicated that the deformation twinning was indeed triggered during HCPEB irradiation. It is suggested that high value of stress and strain rate induced by rapid heating and cooling due to HCPEB irradiation may cause the shifting of whole atomic planes simultaneously. Additionally, some slipping systems may be suppressed due to the geometric confinement by thinned size of surface layer, which can promote the initiation of deformation twinning. | CAI Jie JI Le YANG ShengZhi WANG XiaoTong LI Yan HOU XiuLi GUAN QingFeng | 2013 | Chinese Science Bulletin2013,58,20: | 7 |
| 6 | A naturally occurring CD8^+CD122^+ T-cell subset as a memory-like Treg family显示文摘尽管有 CD4 + CD25 + 规章的 T 房间(Tregs ) 在过去的十年期间,在他们的临床的翻译以后的进步仍然保持停滞。增长证据建议那自然地发生的 CD8 + CD122 + T 房间也是有能力的 Tregs 禁止 T 房间回答并且象 alloimmunity 一样压制 autoimmunity。事实上,他们是像记忆的 Tregs 类似于一个中央记忆 T 房间(T 厘米 ) 显型。位于他们的抑制下面的机制仍然不好被理解,尽管他们可以包括 IL-10 生产。我们最近证明了那个规划 death-1 (PD-1 ) 表达式区分在之间规章并且存储器 CD8 + CD122 + T 房间和那 CD8 + CD122 + Tregs 经历更快的 homeostatic 增长并且比常规 CD4 + CD25 + Tregs。这些调查结果可以为在诊所加速有效 Treg 治疗打开调查的一根新线。在这评论,我们在 CD8 + CD122 + Treg 在诊所研究并且讨论他们的显型,在 autoimmunity 和 alloimmunity 的镇压角色,功能的要求,行动的机制和潜在的应用。 | Shanshan Li Qingfeng Xie Yuqun Zeng Chuan Zou Xusheng Liu Shouhai Wu Haixia Deng Yang Xu Xian C Li Zhenhua Dai | 2014 | Cellular & Molecular Immunology2014,11,4: | 6 |
| 7 | Massive cranium from Harbin in northeastern China establishes a new Middle Pleistocene human lineage显示文摘It has recently become clear that several human lineages coexisted with Homo sapiens during the late Middle and Late Pleistocene.Here,we report an archaic human fossil that throws new light on debates concerning the diversification of the Homo genus and the origin of H.sapiens.The fossil was recovered in Harbin city in northeastern China,with a minimum uranium-series age of 146 ka.This cranium is one of the best preserved Middle Pleistocene human fossils.Its massive size,with a large cranial capacity(1,420 mL)falling in the range of modern humans,is combined with a mosaic of primitive and derived characters.It differs from all the other named Homo species by presenting a combination of features,such as long and low cranial vault,a wide and low face,large and almost square orbits,gently curved but massively developed supraorbital torus,flat and low cheekbones with a shallow canine fossa,and a shallow palate with thick alveolar bone supporting very large molars.The excellent preservation of the Harbin cranium advances our understanding of several less-complete late Middle Pleistocene fossils from China,which have been interpreted as local evolutionary intermediates between the earlier species Homo erectus and later H.sapiens.Phylogenetic analyses based on parsimony criteria and Bayesian tip-dating suggest that the Harbin cranium and some other Middle Pleistocene human fossils from China,such as those from Dali and Xiahe,form a third East Asian lineage,which is a part of the sister group of the H.sapiens lineage.Our analyses of such morphologically distinctive archaic human lineages from Asia,Europe,and Africa suggest that the diversification of the Homo genus may have had a much deeper timescale than previously presumed.Sympatric isolation of small populations combined with stochastic long-distance dispersals is the best fitting biogeographical model for interpreting the evolution of the Homo genus. | Xijun Ni Qiang Ji Wensheng Wu Qingfeng Shao Yannan Ji Chi Zhang Lei Liang Junyi Ge Zhen Guo Jinhua Li Qiang Li Rainer Grun Chris Stringer | 2021 | The Innovation2021,2,3: | 6 |
| 8 | Molecular characteristics of the omp A gene of serotype B Chlamydia trachomatis in Qinghai Tibetan primary school students显示文摘To study the molecular characteristics of Chlamydia trachomatis, the major outer membrane protein gene(omp A) of C. trachomatis from primary school students with trachoma residing in the Qinghai Tibetan area was sequenced and compared with the same serotype in Gen Bank. In Jianshetang Primary School and Galeng Central Primary School in the Galeng Tibetan Township of Qinghai Haidong Sala Autonomous County, scraped samples were collected from the upper tarsal conjunctiva and lower conjunctival sac of both eyes of 45 students with trachoma, stored at 4°C, and transported to Beijing Tongren Hospital by air within 24 h. The samples were screened for C. trachomatis by real-time PCR. The omp A gene from the C. trachomatis-positive samples was amplified by nested PCR. The serotype was confirmed by National Center for Biotechnology Information(NCBI) BLAST search and homology analysis. The entire omp A gene sequence was compared with the corresponding gene sequences of serotype B strains available in Gen Bank. Of the 45 students aged 6–13 years with trachoma, 26 C. trachomatis-positive students were identified by the initial real-time PCR screening(average age,(9.09±1.63) years; sex ratio, 1.0), accounting for 57.78%(26/45). The cycle threshold values for real-time PCR were 16.79–37.77. Half(13/26) of C. trachomatis-positive students had a bacterial copy number of >105. The compliance rate of the omp A gene sequences with the C. trachomatis serotype B strains in Gen Bank was up to 99%. Two novel genetic mutations were found when the omp A gene was compared with those of the 11 serotype B strains in Gen Bank. The two non-synonymous mutations were located at(i) position 271 in the second constant domain, an adenine(A) to guanine(G) substitution(ACT?GCT), changing the amino acid at position 91 from threonine to alanine(Thr?Ala) in all 26 strains; and(ii) position 887 in the fourth variable domain, a cytosine(C) to thymine(T) substitution(GCA?GTA), changing the amino acid at residue 296 from alanine to valine(Ala?Val) in four of the 26 strains. Six mutations were identified relative to ATCC VR-573. The strains could be divided into two gene clusters according to the mutation at nucleotide position 887: CQZ-1(China Qinghai Tibetan-1) and CQZ-2(China Qinghai Tibetan-2). We thus detected two novel serotype B mutant strains of C. trachomatis among study subjects with trachoma. | Xue Li Shaoya Zhang Qingfeng Liang Mei Wang Ailian Hu Xiuyuan Li Benshan Yang Mingxin Zhang Ningli Wang Xinxin Lu | 2016 | Science China(Life Sciences)2016,59,6: | 6 |
| 9 | Zeolitic Imidazolate Framework 8-Derived Au@ZnO for Efficient and Robust Photocatalytic Degradation of Tetracycline显示文摘Summary of main observation and conclusion Tetracycline (TC) and other antibiotics accumulated in groundwater and soil pollute ecological environment and threaten human health. Gold nan oparticles doped on photocatalysts are able to enhance the photodegradation efficiency during removing these antibiotics, but preparation of Au nanoparticles of well-dispersion on photocatalysts remains challenging. In this work, zeolite imidazolate (ZIF-8) was employed as the precursor to prepare Au@ZnO photocatalyst via impregnation and in-situ reduction method to efficiently degrade the tetracycline in the aqueous solution. Au nanoparticles are of 10 nm in size and uniformly dispersed on the surfaces of ZnO microstructures. The as-prepared Au@ZnO is able to remove 85.5% of TC of 0.010 mg/mL within 2h, presenting higher photocatalytic activity than pure ZnO catalyst. Most importantly, the catalyst shows its superior stability after five cycles without structure and activity changing. The mechanism of the photocatalytic degradation was discussed in detail. | Bijun Gao Jin Zhou Hongliang Wang Guping Zhang Jinghui He Qingfeng Xu Najun Li Dongyun Chen Hua Li Jianmei Lu | 2019 | Chinese Journal of Chemistry2019,37,2: | 6 |
| 10 | Matrix porosity calculation in volcanic and dolomite reservoirs and its application显示文摘矩阵孔计算断裂并且 vuggy 水库例如 volcanics 和捱过的白云石,是着急地需要在记载得好的评估解决的问题之一。在这篇论文,我们首先比较为从有矩阵孔公式的完整的直径流纹岩核心实验的孔计算的一个实验公式通常使用了。我们讨论实验公式的适用性在断裂并且 vuggy 水库,例如中介基本的 volcanics 和捱过的白云石。基于核心分析数据,我们的实验公式的计算的孔的错误分发和在这些水库的公式被给的另外的孔。统计错误分析显示我们的实验公式比另外的孔公式提供更高的精确。当孔在 1.5% 和 15% 之间时,声学的实验公式能不仅为酸的 volcanics 而且在折断的其它和 vuggy 水库被使用,例如中介基本的 volcanics 并且捱过白云石。而且,公式能在孔计算上减少地上凿穿增大和岩石改变的效果。 | Li Ning Wu Hongliang Feng Qingfu Wang Kewen Shi Yujiang Li Qingfeng Luo Xinping | 2009 | Applied Geophysics2009,6,3: | 6 |
| 11 | The chimeric genes in the hybrid lineage of Carassius auratus cuvieri(♀)×Carassius auratus red var.(♂)显示文摘Hybridization can combine the genomes of different strains or species, which leads to changes of genotype and phenotype in the hybrids. In this study, we aimed to investigate the genetic variations of hybrids(WR-F1 and WR-F2) derived from the intraspecific hybridization of white crucian carp(Carassius auratus cuvieri, WCC, ♀) and red crucian carp(Carassius auratus red var., RCC, ♂). Here, we compared the orthologous genes in the liver transcriptomes of hybrids with those of WCC and RCC, and classified the orthologous genes into eight gene patterns within three categories(chimera, mutant, and biparental origin genes).The results revealed 19.04%, 4.17% chimeric genes and 6.90%, 5.05% mutations of orthologous genes in WR-F1 and WR-F2 respectively. Seventeen of twenty-three characterized genes(77%) were confirmed to be the chimeras at the genomic DNA level.The GO classification discovered that some chimeric and mutant genes were related to metabolic process, immune system and developmental process in WR-F1. Our results provide the new evidence that hybridization can combine the parental genomes,leading to changes in the genotype of the resultant hybrids. This is the first report on the formation of chimeric genes from fish intraspecific hybridization, which is potentially interesting from the context of both evolution and the genetic breeding of fish. | Qingfeng Liu Yanhua Qi Qiuli Liang Xiujuan Xu Fangzhou Hu Jing Wang Jun Xiao Shi Wang Wuhui Li Min Tao Qinbo Qin Rurong Zhao Zhanzhou Yao Shaojun Liu | 2018 | Science China(Life Sciences)2018,61,9: | 6 |
| 12 | A phosphatidic acid-binding lncRNA SNHG9 facilitates LATS1 liquid–liquid phase separation to promote oncogenic YAP signaling显示文摘Long noncoding RNAs(lncRNAs)are emerging as a new class of important regulators of signal transduction in tissue homeostasis and cancer development.Liquid–liquid phase separation(LLPS)occurs in a wide range of biological processes,while its role in signal transduction remains largely undeciphered.In this study,we uncovered a lipid-associated lncRNA,small nucleolar RNA host gene 9(SNHG9)as a tumor-promoting lncRNA driving liquid droplet formation of Large Tumor Suppressor Kinase 1(LATS1)and inhibiting the Hippo pathway.Mechanistically,SNHG9 and its associated phosphatidic acids(PA)interact with the C-terminal domain of LATS1,promoting LATS1 phase separation and inhibiting LATS1-mediated YAP phosphorylation.Loss of SNHG9 suppresses xenograft breast tumor growth.Clinically,expression of SNHG9 positively correlates with YAP activity and breast cancer progression.Taken together,our results uncover a novel regulatory role of a tumor-promoting lncRNA(i.e.,SNHG9)in signal transduction and cancer development by facilitating the LLPS of a signaling kinase(i.e.,LATS1). | Rui-Hua Li Tian Tian Qi-Wei Ge Xin-Yu He Cheng-Yu Shi Jun-Hong Li Zhen Zhang Fang-Zhou Liu Ling-Jie Sang Zuo-Zhen Yang Ya-Zhuo Liu Yan Xiong Qingfeng Yan Xu Li Huai-Qiang Ju Jian Liu Liang-Jing Wang Jian-Zhong Shao Wenqi Wang Tianhua Zhou Aifu Lin | 2021 | Cell Research2021,31,10: | 6 |
| 13 | Advancement toward Polymer Electrolyte Membrane Fuel Cells at Elevated Temperatures显示文摘Elevation of operational temperatures of polymer electrolyte membrane fuel cells(PEMFCs)has been demonstrated with phosphoric acid-doped polybenzimidazole(PA/PBI)membranes.The technical perspective of the technology is simplified construction and operation with possible integration with,e.g.,methanol reformers.Toward this target,significant efforts have been made to develop acid-base polymer membranes,inorganic proton conductors,and organic-inorganic composite materials.This report is devoted to updating the recent progress of the development particularly of acid-doped PBI,phosphate-based solid inorganic proton conductors,and their composite electrolytes.Long-term stability of PBI membranes has been well documented,however,at typical temperatures of 160℃.Inorganic proton-conducting materials,e.g.,alkali metal dihydrogen phosphates,heteropolyacids,tetravalent metal pyrophosphates,and phosphosilicates,exhibit significant proton conductivity at temperatures of up to 300℃ but have so far found limited applications in the form of thin films.Composite membranes of PBI and phosphates,particularly in situ formed phosphosilicates in the polymer matrix,showed exceptionally stable conductivity at temperatures well above 200℃.Fuel cell tests at up to 260℃ are reported operational with good tolerance of up to 16%CO in hydrogen,fast kinetics for direct methanol oxidation,and feasibility of nonprecious metal catalysts.The prospect and future exploration of new proton conductors based on phosphate immobilization and fuel cell technologies at temperatures above 200℃ are discussed. | Jin Zhang David Aili Shanfu Lu Qingfeng Li and San Ping Jiang | 2020 | Research2020,,1: | 6 |
| 14 | Does an extended mediastinal lymphadenectomy improve outcome after R0 resection in lung cancer?显示文摘Objective: This retrospective study was conducted to investigate the impact of more extended mediastinal lymphadenectomy on the outcome of lung cancer patients treated with R0 resection.Methods: During the investigation period, 325 lung cancer cases were enlisted and 278 cases entered the analysis. The patients were divided into Control group(n=116) and Research group(n=162) according to the different extents of mediastinal lymph node clearance at different time periods. Three major parameters were retrospectively assessed to compare the quality of surgical care: extent of lymph node clearance, resection volume, and postoperative recovery process and common complications. Comparison of the outcome between two groups was carried out.Results: Research group showed a significant quality improvement of lymphadenectomy, such as more mediastinal node stations investigated(more than 3 N2 stations investigated: Research group, 90.7% vs. Control group, 55.2%; P=0.001) and more nodes collection(total nodes 26.1±10.0 vs. 19.1±8.3, P=0.000; N2 nodes 15.5±7.2 vs. 9.8±5.6, P=0.000). However, overall survival(OS) and disease-free survival(DFS) were not significantly different either between two groups(5-year OS: Control group, 56.4±4.6% vs. Research group, 62.6±4.3%; P=0.271) or between subgroups from stage I to IIIa. TNM stage and histology were significant factors associated with OS and DFS in multivariate analysis; extent of mediastinal lymphadenectomy was not associated with OS or DFS.Conclusions: More radical mediastinal lymphadenectomy may not lead to an improved oncological outcome for lung cancer treated with R0 resection. | Nan Wu Shi Yan Chao Lv Shaolei Li Yuan Feng Yuzhao Wang Jia Wang Qingfeng Zheng Yue Yang | 2014 | Chinese Journal of Cancer Research2014,26,2: | 5 |
| 15 | Multimetallic AuPd@Pd@Pt core-interlayer-shell icosahedral electrocatalysts for highly efficient oxygen reduction reaction显示文摘Incorporating Pt with core metals into Pt-based core-shell catalysts is regarded as a promising strategy to substantially enhance the catalytic properties towards oxygen reduction reaction(ORR) in fuel cells due to the synergetic effect between distinct metals. In this wok, ultrathin Pt skins with two atomic layers were epitaxially coated on as-prepared icosahedral Au_50Pd_50, Au_60Pd_40 and Au_66Pd_34 nanocrystal seeds,which are constructed with alloyed cores and Pd shells with different thickness. Through electron microscopic characterizations, Pd interlayers with tunable thickness of 3, 6, and 12 atomic layers can be found in the Au_66Pd_34@Pt, Au_60 Pd_40@Pt and Au_50Pd_50@Pt icosahedra, respectively. These icosahedral Au Pd@Pd@Pt nanocrystals show substantially enhanced activities and durabilities in electrocatalytic measurements towards ORR compared to Au_75Pd_25@Pt icosahedra without Pd interlayer and commercial Pt/C catalysts. Specifically, Au_60Pd_40@Pt icosahedra with 6 atomically thick Pd interlayer display the best electrocatalytic performances, whose mass activities before and after durability tests of 50,000 cycles are11.6 and 30.2 times, respectively, as high as that of the commercial Pt/C. | Qingfeng Xu Wenlong Chen Yucong Yan Zhemin Wu Yi Jiang Junjie Li Ting Bian Hui Zhang Jianbo Wu Deren Yang | 2018 | Science Bulletin2018,63,8: | 5 |
| 16 | Atomistic Surface Passivation of CH_(3)NH_(3)PbI_(3) Perovskite Single Crystals for Highly Sensitive Coplanar-Structure X-Ray Detectors显示文摘Organic-inorganic halide perovskites(OIHPs)are recognized as the promising next-generation X-ray detection materials.However,the device performance is largely limited by the ion migration issue of OIHPs.Here,we reported a simple atomistic surface passivation strategy with methylammonium iodide(MAI)to remarkably increase the ion migration activation energy of CH_(3)NH_(3)PbI_(3)single crystals.The amount of MAI deposited on the crystal surface is finely regulated by a self-assemble process to effectively suppress the metallic lead defects,while not introducing extra mobile ions,which results in significantly improved dark current stability of the coplanar-structure devices under a large electric field of 100Vmm^(-1).The X-ray detectors hence exhibit a record-high sensitivity above 700,000μC Gy^(-1)_(air) cm^(-2)under continuum X-ray irradiation with energy up to 50 keV,which enables an ultralow X-ray detection limit down to 1.5 nGy_(air)s^(-1).Our findings will allow for the dramatically reduced X-ray exposure of human bodies in medical imaging applications. | Yilong Song Liqi Li Weihui Bi Mingwei Hao Yifei Kang Anran Wang Zisheng Wang Hanming Li Xiaohui Li Yanjun Fang Deren Yang Qingfeng Dong | 2020 | Research2020,,1: | 5 |
| 17 | Comparative Analysis of Fractional Vegetation Cover Estimation Based on Multi-sensor Data in a Semi-arid Sandy Area显示文摘The estimation of fractional vegetation cover(FVC) is important for identifying and monitoring desertification, especially in arid and semiarid regions. By using regression and pixel dichotomy models, we present the comparison of Sentinel-2A(S2) multispectral instrument(MSI) and Landsat 8(L8) operational land imager(OLI) data regarding the retrieval of FVC in a semi-arid sandy area(Mu Us Sandland, China, in August 2016). A combination of unmanned aerial vehicle(UAV) high-spatial-resolution images and field plots were used to produce verified data. Based on a normalized difference vegetation index(NDVI) regression model, the results showed that, compared with that of L8, the coefficient of determination(R2) of S2 increased by 26.0%, and the root mean square error(RMSE) and the sum of absolute error(SAE) decreased by 3.0% and 11.4%, respectively. For the ratio vegetation index(RVI) regression model, compared with that of L8, the R2 of S2 increased by 26.0%, and the RMSE and SAE decreased by 8.0% and 20.0%, respectively. When the pixel dichotomy model was used, compared with that of L8, the RMSE of S2 decreased by 21.3%, and the SAE decreased by 26.9%. Overall, S2 performed better than L8 in terms of FVC inversion. Additionally, in this paper, we develop a verified scheme based on UAV data in combination with the object-based classification method. This scheme is feasible and sufficiently robust for building relationships between field data and inversion results from satellite data. Further, the synergy of multi-source sensors(especially UAVs and satellites) is a potential effective way to estimate and evaluate regional ecological environmental parameters(FVC). | LIU Qiuyu ZHANG Tinglong LI Yizhe LI Ying BU Chongfeng ZHANG Qingfeng | 2019 | Chinese Geographical Science2019,29,1: | 4 |
| 18 | Syndecan-2, negatively regulated by miR-20b-5p, contributes to 5-fluorouracil resistance of colorectal cancer cells via the JNK/ERK signaling pathway显示文摘5-Fluorouracil (5-FU) resistance has been long considered as an obstacle to the efficacy of chemotherapy in colorectal cancer (CRC). In this study, we demonstrated the role of miR-20b-5p-regulated syndecan-2 (SDC2) in 5-FU resistance of CRC cells. 5-FU-resistant SW480 CRC cells were established by treatment of SW480 cells with stepwise increase of 5-FU concentration. The results showed that SDC2 was expressed significantly higher in SW480/5-FU cells than in SW480/WT cells as revealed by quantitative real-time polymerase chain reaction and western blot analysis. MTT assay and BrdU assay showed that SDC2 overexpression led to increased cell survival rate, while SDC2 knockdown reversed the drug resistance of SW480/5-FU cells. Wound healing and transwell invasion assays revealed that knockdown of SDC2 inhibited the migratory and invasive ability of SW480/5-FU cells. Moreover, animal experiments indicated that si-SDC2 plays a suppressive role in tumor growth in vivo. We also confirmed that miR-20b-5p interacted with SDC2, which reversed the effect of SDC2 in SW480/5-FU cells via the c-Jun N-terminal kinase (JNK)/extracellular regulated protein kinases (ERK) signaling pathway. These findings showed that JNK/ERK signaling pathway is involved in miR-20b-5p/SDC2 axis-mediated 5-FU resistance in SW480/5-FU cells, indicating that the miR-20b-5p/SDC2 axis is a potential target for reversing 5-FU resistance in CRC. | Ruheng Hua Yan Zhang Xiyue Yan Dong Tang Xiaolong Li Qingfeng Ni Daorong Wang Jianwei Zhu | 2021 | Acta Biochimica et Biophysica Sinica2021,53,11: | 4 |
| 19 | Targeted disruption of tyrosinase causes melanin reduction in Carassius auratus cuvieri and its hybrid progeny显示文摘The white crucian carp(Carassius auratus cuvieri,WCC) not only is one of the most economically important fish in Asia,characterized by strong reproductive ability and rapid growth rates,but also represents a good germplasm to produce hybrid progenies with heterosis.Gene knockout technique provides a safe and acceptant way for fish breeding.Achieving gene knockout in WCC and its hybrid progeny will be of great importance for both genetic studies and hybridization breeding.Tyrosinase(TYR) is a key enzyme in melanin synthesis.Depletion of tyr in zebrafish and mice results in mosaic pigmentation or total albinism.Here,we successfully used CRISPR-Cas9 to target tyr in WCC and its hybrid progeny(WR) derived from the cross of WCC(♀) and red crucian carp(Carassius auratus red var.,RCC,♂).The level of TYR protein was significantly reduced in mutant WCC.Both the mutant WCC and the mutant WR showed different degrees of melanin reduction compared with the wild-type sibling control fish,resulting from different mutation efficiency ranging from 60% to 90%.In addition,the transcriptional expression profiles of a series of pivotal pigment synthesis genes,i.e.tyrp1,mitfa,mitfb,dct and sox10,were down-regulated in tyr-CRISPR WCC,which ultimately caused a reduction in melanin synthesis.These results demonstrated that tyr plays a key role in melanin synthesis in WCC and WR,and CRISPR-Cas9 is an effective tool for modifying the genome of economical fish.Furthermore,the tyr-CRISPR models could be valuable in understanding fundamental mechanisms of pigment formation in non-model fish. | Qingfeng Liu Yanhua Qi Qiuli Liang Jia Song Junmei Liu Wuhui Li Yuqin Shu Min Tao Chun Zhang Qinbo Qin Jing Wang Shaojun Liu | 2019 | Science China(Life Sciences)2019,62,9: | 4 |
| 20 | Control technology and coordination deformation mechanism of rise entry group with high ground stress显示文摘Based on engineering practices of Wuyang Coal Mine, we carried out X-ray diffract researches on No. 3 coal; and the rocks of its roof and floor by XRD meter, and simulated the interactive effect of the surrounding rock deformation by FLAC2D5.0 numerical simulation software under the condition of different tunneling method of multimine roadway in parallel. The internal structures of the surrounding rocks of 76 belt roadway were monitored by borehole observation instruments; and then, we analyzed the reason of failure and deformation of surrounding rocks of several rise entry, and proposed the technical measures for controlling interactive effect of several rise entry surrounding rock deformation at last. For the thickness seam rise roadway, two conclusions were drawn: one is that the co-deformation among roadway groups mainly reflect on that both shear failure and deformation in coal pillar among roadways have decreased the width of pillar core region and clamping action of coal pillar to roof strata, increased the actual span of roof strata, intensified the flexural failure of roof strata and prized the bed separation of roof deep rock strata. The other conclusion is that the factors controlling the interactive deformation among roadways is obvious when appropriate re-adjustment in construction sequence of the tunneling of multimine parallel roadways because the construction sequence among roadways also has great effects on deformation of the surrounding rock in roadway. | Li Qingfeng | 2012 | International Journal of Mining Science and Technology2012,22,3: | 4 |