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Evaluation of the Gastric Microbiome in Patients with Chronic Superficial Gastritis and Intestinal Metaplasia 被引量:8
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作者 Ying Liu yongjun ma Caiqun Huang 《Chinese Medical Sciences Journal》 CAS CSCD 2022年第1期44-51,共8页
Objective To evaluate the gastric microbiome in patients with chronic superficial gastritis(CSG)and intestinal metaplasia(IM)and investigate the influence of Helicobacter pylori(H.pylori)on the gastric microbiome.Meth... Objective To evaluate the gastric microbiome in patients with chronic superficial gastritis(CSG)and intestinal metaplasia(IM)and investigate the influence of Helicobacter pylori(H.pylori)on the gastric microbiome.Methods Gastric mucosa tissue samples were collected from 54 patients with CSG and IM,and the patients were classified into the following four groups based on the state of H.pylori infection and histology:H.pylori-negative CSG(n=24),H.pylori-positive CSG(n=14),H.pylori-negative IM(n=11),and H.pylori-positive IM(n=5).The gastric microbiome was analyzed by 16S rRNA gene sequencing.Results H.pylori strongly influenced the bacterial abundance and diversity regardless of CSG and IM.In H.pylori-positive subjects,the bacterial abundance and diversity were significantly lower than in H.pylori-negative subjects.The H.pylori-negative groups had similar bacterial composition and bacterial abundance.The H.pylori-positive groups also had similar bacterial composition but different bacterial relative abundance.The relative abundance of Neisseria,Streptococcus,Rothia,and Veillonella were richer in the I-HP group than in G-HP group,especially Neisseria(t=175.1,P<0.001).Conclusions The gastric microbial abundance and diversity are lower in H.pylori-infected patients regardless of CSG and IM.Compared to H.pylori-positive CSG group and H.pylori-positive IM,the relative abundance of Neisseria,Streptococcus,Rothia,and Veillonella is higher in H.pylori-positive patients with IM than in H.pylori-positive patients with CSG,especially Neisseria. 展开更多
关键词 chronic superficial gastritis intestinal metaplasia Helicobacter pylori gastric microbiome
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Preparation of CeO_2 Nanoparticles and Its Application to Ion-selective Electrodes Based on Acetyl Cellulose 被引量:1
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作者 Jinzhang Gao Fei Guan +4 位作者 yongjun ma Wu Yang Jingwan Kang Hualing Deng Youli Qi 《Rare Metals》 SCIE EI CAS CSCD 2001年第4期217-221,共4页
CeO2 nanoparticles with an average diameter of about 30 nm were prepared by sol-gel method at lower temperature. The gel, transformed from the aqueous solution of metal nitrate and citric acid, can be combusted comple... CeO2 nanoparticles with an average diameter of about 30 nm were prepared by sol-gel method at lower temperature. The gel, transformed from the aqueous solution of metal nitrate and citric acid, can be combusted completely at lower temperature. The redox behavior and the crystallization process of the dried gel were studied by thermogravimetric analysis and infrared spectroscopy. The synthesized powders were characterized by X-ray powder diffraction and transmission electron microscopy. In addition, rare earth elements ion-selective electrodes based on acetyl cellulose were prepared using ultra fine cerium oxide powders. 展开更多
关键词 CeO2 nanoparticles sol-gel method ion-selective electrode acetyl cellulose
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Highly efficient and aberration-free off-plane grating spectrometer and monochromator for EUV—soft X-ray applications 被引量:1
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作者 Jie Li Kui Li +14 位作者 Xiaoshi Zhang Dimitar Popmintchev Hao Xu Yutong Wang Ruixuan Li Guangyin Zhang Jiyue Tang Jin Niu yongjun ma Runyu Meng Changjun Ke Jisi Qiu Yunfeng ma Tenio Popmintchev Zhongwei Fan 《Light(Science & Applications)》 SCIE EI CSCD 2024年第1期68-79,共12页
We demonstrate a novel flat-field,dual-optic imaging EUV—soft X-ray spectrometer and monochromator that attains an unprecedented throughput efficiency exceeding 60%by design,along with a superb spectral resolution of... We demonstrate a novel flat-field,dual-optic imaging EUV—soft X-ray spectrometer and monochromator that attains an unprecedented throughput efficiency exceeding 60%by design,along with a superb spectral resolution ofλ/Δλ>200 accomplished without employing variable line spacing gratings.Exploiting the benefits of the conical diffraction geometry,the optical system is globally optimized in multidimensional parameter space to guarantee optimal imaging performance over a broad spectral range while maintaining circular and elliptical polarization states at the first,second,and third diffraction orders.Moreover,our analysis indicates minimal temporal dispersion,with pulse broadening confined within 80 fs tail-to-tail and an FWHM value of 29 fs,which enables ultrafast spectroscopic and pump-probe studies with femtosecond accuracy.Furthermore,the spectrometer can be effortlessly transformed into a monochromator spanning the EUV—soft X-ray spectral region using a single grating with an aberration-free spatial profile.Such capability allows coherent diffractive imaging applications to be conducted with highly monochromatic light in a broad spectral range and extended to the soft X-ray region with minimal photon loss,thus facilitating state-of-the-art imaging of intricate nano-and bio-systems,with a significantly enhanced spatiotemporal resolution,down to the nanometer–femtosecond level. 展开更多
关键词 chromato Highly EXCEEDING
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Early Warning of Agricultural Industrial Safety in Hunan Province:Based on Entropy Weighted Grey Relational Analyses
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作者 Wenxing XIAO yongjun ma +1 位作者 Yanhua LIU Juan ZHANG 《Asian Agricultural Research》 2020年第9期16-20,27,共6页
In this article,early warning analyses on agricultural industrial safety in Hunan Province from 2001 to 2013 are performed by constructing a four-indexed evaluation system and adopting the entropy weighted grey relati... In this article,early warning analyses on agricultural industrial safety in Hunan Province from 2001 to 2013 are performed by constructing a four-indexed evaluation system and adopting the entropy weighted grey relational analysis model.The results show that Hunan's agricultural industrial safety showed a good trend of transforming from"heavy warning"to"light warning";the early warning results of agricultural industrial productivity index and the overall index remained consistent and performed well;the agricultural industrial competitiveness index and dependence index changed frequently and fluctuated around"medium warning";and the control power index showed a deteriorating trend from"light warning"to"heavy warning".Therefore,support shall be increased continuously for the agricultural industry in terms of system construction,policy support and capital supply,and technological innovations and system innovations in the agricultural industry shall be promoted,especially for the improvement of the independent control of domestic capital,truly ensuring the efficiency,stability and safety of the agricultural industry development. 展开更多
关键词 Agricultural industrial safety Four-indexed system Grey relational analysis
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Evaluation of Agricultural Industry Safety in Hunan Province——Based on Factor Analysis and Fuzzy Comprehensive Evaluation
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作者 Wenxing XIAO yongjun ma +1 位作者 Yanhua LIU Juan ZHANG 《Asian Agricultural Research》 2018年第3期23-28,32,共7页
By constructing the index system of " four forces" and adopting the fuzzy comprehensive evaluation model under the new membership function,this paper makes an empirical analysis on the safety of agricultural... By constructing the index system of " four forces" and adopting the fuzzy comprehensive evaluation model under the new membership function,this paper makes an empirical analysis on the safety of agricultural industry in Hunan Province from 2001 to 2013. The results show that the safety degree of Hunan agricultural industry is always in the range of " basically safe" and above,it was in the range of " safe" in 2010 and 2011,in the range of " very safe" in 2013,and in the range of " basically safe" in the other years; the indices of productive force,competitiveness and dependency of agricultural industry is always in the state of " basically safe" or above,while the index of control force of agricultural industry is in the trend of changing from " basically safe" to " unsafe". Therefore,it is necessary to accelerate the innovation process of agricultural industry and improve the export quality of agricultural products,especially to establish a stricter market mechanism for foreign capital entry and foreign capital merger and acquisition,improve the control power of agricultural industry,and provide favorable guarantee for the safety of agricultural industry. 展开更多
关键词 Agricultural industry safety Index system of "four forces" Fuzzy comprehensive evaluation
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Clinical applications of metagenomics next-generation sequencing in infectious diseases
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作者 Ying LIU yongjun ma 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2024年第6期471-484,共14页
Infectious diseases are a great threat to human health.Rapid and accurate detection of pathogens is important in the diagnosis and treatment of infectious diseases.Metagenomics next-generation sequencing(mNGS)is an un... Infectious diseases are a great threat to human health.Rapid and accurate detection of pathogens is important in the diagnosis and treatment of infectious diseases.Metagenomics next-generation sequencing(mNGS)is an unbiased and comprehensive approach for detecting all RNA and DNA in a sample.With the development of sequencing and bioinformatics technologies,mNGS is moving from research to clinical application,which opens a new avenue for pathogen detection.Numerous studies have revealed good potential for the clinical application of mNGS in infectious diseases,especially in difficult-to-detect,rare,and novel pathogens.However,there are several hurdles in the clinical application of mNGS,such as:(1)lack of universal workflow validation and quality assurance;(2)insensitivity to high-host background and low-biomass samples;and(3)lack of standardized instructions for mass data analysis and report interpretation.Therefore,a complete understanding of this new technology will help promote the clinical application of mNGS to infectious diseases.This review briefly introduces the history of next-generation sequencing,mainstream sequencing platforms,and mNGS workflow,and discusses the clinical applications of mNGS to infectious diseases and its advantages and disadvantages. 展开更多
关键词 Metagenomics next-generation sequencing(mNGS) Infectious disease Cerebrospinal fluid(CSF) Oxford Nanopore Technologies(ONT) MICROBIOME
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Hexagonal boron nitride nanosheet for effective ambient N2 fixation to NH3 被引量:8
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作者 Ya Zhang Huitong Du +10 位作者 yongjun ma Lei Ji Haoran Guo Ziqi Tian Hongyu Chen Hong Huang Guanwei Cui Abdullah M. Asiri Fengli Qu Liang Chen Xuping Sun 《Nano Research》 SCIE EI CAS CSCD 2019年第4期919-924,共6页
Industrial production of NH3 from N2 and H2 significantly relies on Haber-Bosch process,which suffers from high energy consume and CO2 emission.As a sustainable and environmentally-benign alternative process,electroch... Industrial production of NH3 from N2 and H2 significantly relies on Haber-Bosch process,which suffers from high energy consume and CO2 emission.As a sustainable and environmentally-benign alternative process,electrochemical artificial N2 fixation at ambient conditions,however,is highly required efficient electrocatalysts.In this study,we demonstrate that hexagonal boron nitride nanosheet (h-BNNS) is able to electrochemically catalyze N2 to NH3.In acidic solution,h-BNNS catalyst attains a high NH3 formation rate of 22.4 μg·h-1·mg-1cat.and a high Faradic efficiency of 4.7% at-0.75 V vs.reversible hydrogen electrode,with excellent stability and durability.Density functional theory calculations reveal that unsaturated boron at the edge site can activate inert N2 molecule and significantly reduce the energy barrier for NH3 fonmation. 展开更多
关键词 boron NITRIDE NANOSHEET N2 reduction reaction NH3 ELECTROSYNTHESIS AMBIENT conditions density functional theory
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Dynamic changes in soil chemical properties and microbial community structure in response to different nitrogen fertilizers in an acidified celery soil 被引量:10
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作者 Yuping Wu Jiangxing Wu +6 位作者 yongjun ma Ying Lian Hui Sun Danchao Xie Yaying Li Philip C.Brookes Huaiying Yao 《Soil Ecology Letters》 CAS 2019年第3期105-113,共9页
To determine the effects of different kinds of nitrogen fertilizer,especially high-efficiency slowrelease fertilizers,on soil pH,nitrogen(N)and microbial community structures in an acidic celery soil,four treatments(C... To determine the effects of different kinds of nitrogen fertilizer,especially high-efficiency slowrelease fertilizers,on soil pH,nitrogen(N)and microbial community structures in an acidic celery soil,four treatments(CK,no N fertilizer;NR,urea;PE,calcium cyanamide fertilizer;and SK,controlled-release N fertilizer)were applied,and soil pH,total soil N,inorganic N,and soil microbial biomass C were analyzed.Phospholipid fatty acids(PLFAs)were extracted and detected using the MIDI Sherlock microbial identification system.The PE treatment significantly improved soil pH,from 4.80 to>6.00,during the whole growth period of the celery,and resulted in the highest celery yield among the four treatments.After 14 d application of calcium cyanamide,the soil nitrate content significantly decreased,but the ammonium content significantly increased.The PE treatment also significantly increased soil microbial biomass C during the whole celery growth period.Canonical variate analysis of the PLFA data indicated that the soil microbial community structure in the CK treatment was significantly different from those in the N applied treatments after 49 d fertilization.However,there was a significant difference(P<0.05)in soil microbial community structure between the PE treatment and the other three treatments at the end of the experiment.Calcium cyanamide is a good choice for farmers to use on acidic celery land because it supplies sufficient N,and increases soil pH,microbial biomass and the yield of celery. 展开更多
关键词 Acidified Calcium cyanamide CELERY Phospholipid fatty acid Soil nitrogen
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