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Localization of ANP-synthesizing cells in rat stomach

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World Journal of Gastroenterology 2006年第35期12卷 5674-5679页

作者： chun-hui Li Li-hui Pan chun-Yu Li Chang-Lin Zhu Wen-Xie Xu Department of Pathology Affiliated Hospital of Chengde Medical College Chengde 067000 Hebei Province China Department of Microbiology and Immunology Chengde Medical College Chengde 067000 Hebei ProvinceChina Department of Surgery Affiliated Hospital for Anus and Intestines Diseases Hospital of Chengde Medical CollegeChengde 067000 Hebei Province China Department of Physiology College of MedicineShanghai Jiaotong University Shanghai 200030 China

AIM: To study the morphological positive expression of antrial natriuretic peptide (ANP)-synthesizing cells and ultrastructural localization and the relationship between ANP-synthesizing cells and microvessel density in the stomach of rats and to analyze the distribution of the three histologically distinct regions of ANP-synthesizing cells. METHODS: Using immunohistochemical techniques, we studied positive expression of ANP-synthesizing cells in rat stomach. A postembedding immunogold microscopy technique was used for ultrastructural localization of ANP-synthesizing cells. Microvessel density in the rat stomach was estimated using tannic acid-ferric chloride (TAFC) method staining. Distribution of ANP-synthesizing cells were studied in different regions of rat stomach histochemically. RESULTS: Positive expression of ANP-synthesizing cells were localized in the gastric mucosa of rats. Localization of ANP-synthesizing cells identified them to be enterochrochromaffin cells (EC) by using a postembedding immunogold electron microscopy technique. EC cells were in the basal third of the cardiac mucosa region. ANP-synthesizing cells existed in different regions of rat stomach and its density was largest in the gastric cardiac region, and the distribution order of ANP-synthesizing cells in density was cardiac region, pyloric region and fundic region in mucosa layer. We have also found a close relationship between ANP-synthesizing cells and microvessel density in gastric mucosa of rats using TAFC staining. CONCLUSION: ANP-synthesizing cells are expressedin the gastric mucosa. EC synthesize ANP. There is a close relationship between ANP-synthesizing cells and microvessel density in gastric mucosa of *** distribution density of ANP-synthesizing cells is largest in the gastric cardiac region.

关键词： Antrial natriuretic peptide-synthesizing cells Microvessel density Close relationship Gastric cardiac region

Aerobic granular sludge formation based on substrate availability:Effects of flow pattern and fermentation pretreatment

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Frontiers of Environmental Science & Engineering 2020年第3期14卷 155-164页

作者： Quan yuan hui Gong Hao Xi Kaijun Wang State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China

The influences of flow patterns(mixed-flow and plug-flow)and fermentation pretreatment on aerobic granular sludge(AGS)formation with various substrate availability levels were investigated by running four identical laboratory-scale sequencing batch reactors(R1-R4),comparing two anaerobic feeding strategies and three kinds of substrates.R1 achieved faster granulation with a fast influent fill step followed by a modified anaerobic mixed-flow phase,but the AGS showed poorer stability with a cracked structure and a high suspended solids concentration in the *** anaerobic plug-flow feeding mode(with influent fed slowly from the bottom)in R2 provided deeper penetration depth for the substance to reach the core of A G S and accordingly strengthen A G S *** acidogenic upflow sludge bed reactor was introduced as a pretreatment to improve the AGS performance by enhancing glucose pre-fermentation(R4).AGS fed with mixed volatile fatty acids(VFA)after glucose fermentation showed similar performance compared with the reactor fed with acetate in the aspects of stability,structure,size distribution and nitrogen removal efficiency,and 74%similarity in the microbial *** actual wastewater with low VFA concentrations,fermentation treatment was suggested as a promising pretreatment for stable AGS granulation and operation.

关键词： Anaerobic plug-flow feeding mode Anaerobic mixed-flow mode Fermentation pretreatment Substrate gradient Penetration depth

Research progress of precise structural regulation of single atom catalyst for accelerating electrocatalytic oxygen reduction reaction

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Journal of Energy Chemistry 2022年第9期31卷 56-72,I0003页

作者： Minmin Wang hui Zhang Yunqi Liu yuan Pan State Key Laboratory of Heavy Oil Processing China University of Petroleum(East China)Qingdao 266580ShandongChin

The development and utilization of renewable clean energy can effectively solve the two major problems of energy and environment. As an efficient power generation device that converts hydrogen energy into electric energy, fuel cell has attracted more and more attention. For fuel cells, the oxygen reduction reaction(ORR) at the cathode is the core reaction, and the design and development of high-performance ORR catalysts remain quite challenging. Since the microenvironment of the active center of single atom catalysts(SACs) has an important influence on its catalytic performance, it has been a research focus to improve the ORR activity and stability of electrocatalysts by adjusting the structure of the active center through reasonable structural regulation methods. In this review, we reviewed the preparation and structure–activity relationship of SACs for ORR. Then, the structural precision regulation methods for improving the activity and stability of ORR electrocatalysts are discussed. And the advanced in-situ characterization techniques for revealing the changes of active sites in the electrocatalytic ORR process are summarized. Finally, the challenges and future design directions of SACs for ORR are discussed. This work will provide important reference value for the design and synthesis of SACs with high activity and stability for ORR.

关键词： Electrocatalyst Oxygen reduction reaction Structure regulation Single atom catalysts In-situ characterization technique

Size effects on process performance and product quality in progressive microforming of shafted gears revealed by experiment and numerical modeling

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Advances in Manufacturing 2023年第1期11卷 1-20页

作者： Jun-yuan Zheng hui Liu Ming-Wang Fu Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongPeople’s Republic of China Research Institute for Advanced Manufacturing The Hong Kong Polytechnic UniversityHung HomKowloonHong KongPeople’s Republic of China

As one of the indispensable actuating components in micro-systems,the shafted microgear is in great production *** is a manufacturing process to produce microgears to meet the *** to the small geometrical size,there are uncertain process performance and product quality issues in this production *** this study,the shafted microgears were fabricated in two different scaling factors with four grain sizes using a progressively extrusion-blanking *** explore the unknown of the process,grain-based modeling was proposed and employed to simulate the entire forming *** results show that when the grains are large,the anisotropy of single grains has an obvious size effect on the forming behavior and process performance;and the produced geometries and surface quality are worsened;and the deformation load is *** deformation zones were identified in the microstructures with different hardness and distributions of stress and *** simulation by using the proposed model successfully predicted the formation of zones and revealed the inhomogeneous deformation in the forming *** undesirable geometries of microgears including material unfilling,burr and inclination were observed on the shaft and teeth of gear,and the inclination size is increased obviously with grain *** avoid the formation of inclination and material unfilling,the punch was redesigned,and a die insert was added to constraint the bottom surface of the gear *** new products had then the better forming quality.

关键词： Microforming Microprocess performance Microforming quality Size effect affected deformation behavior Die design optimization

Wavelet-based L_(1/2) regularization for CS-TomoSAR imaging of forested area

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Journal of Systems Engineering and Electronics 2020年第6期31卷 1160-1166页

作者： BI hui CHENG yuan ZHU Daiyin HONG Wen College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China

Tomographic synthetic aperture radar(TomoSAR)imaging exploits the antenna array measurements taken at different elevation aperture to recover the reflectivity function along the elevation *** these years,for the sparse elevation distribution,compressive sensing(CS)is a developed favorable technique for the high-resolution elevation reconstruction in TomoSAR by solving an L_(1) regularization ***,because the elevation distribution in the forested area is nonsparse,if we want to use CS in the recovery,some basis,such as wavelet,should be exploited in the sparse L_(1/2) representation of the elevation reflectivity *** paper presents a novel wavelet-based L_(2) regularization CS-TomoSAR imaging method of the forested *** the proposed method,we first construct a wavelet basis,which can sparsely represent the elevation reflectivity function of the forested area,and then reconstruct the elevation distribution by using the L_(1/2) regularization *** to the wavelet-based L_(1) regularization TomoSAR imaging,the proposed method can improve the elevation recovered quality efficiently.

关键词： tomographic synthetic aperture radar(TomoSAR) compressive sensing(CS) L_(1/2)regularization wavelet basis

Changes in the activities of key enzymes and the abundance of functional genes involved in nitrogen transformation in rice rhizosphere soil under different aerated conditions

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Journal of Integrative Agriculture 2023年第3期22卷 923-934页

作者： XU chun-mei XIAO De-shun CHEN Song CHU Guang LIU yuan-hui ZHANG Xiu-fu WANG Dan-ying The State Key Laboratoty of Rice Biology China National Rice Research InstituteHangzhou 310006P.R.China

Soil microorganisms play important roles in nitrogen transformation. The aim of this study was to characterize changes in the activity of nitrogen transformation enzymes and the abundance of nitrogen function genes in rhizosphere soil aerated using three different methods(continuous flooding(CF), continuous flooding and aeration(CFA), and alternate wetting and drying(AWD)). The abundances of amoA ammonia-oxidizing archaea(AOA) and ammonia-oxidizing bacteria(AOB), nirS, nirK, and nifH genes, and the activities of urease, protease, ammonia oxidase, nitrate reductase, and nitrite reductase were measured at the tillering(S1), heading(S2), and ripening(S3) stages. We analyzed the relationships of the aforementioned microbial activity indices, in addition to soil microbial biomass carbon(MBC) and soil microbial biomass nitrogen(MBN), with the concentration of soil nitrate and ammonium nitrogen. The abundance of nitrogen function genes and the activities of nitrogen invertase in rice rhizosphere soil were higher at S2 compared with S1 and S3 in all treatments. AWD and CFA increased the abundance of amoA and nifH genes, and the activities of urease, protease, and ammonia oxidase, and decreased the abundance of nirS and nirK genes and the activities of nitrate reductase and nitrite reductase, with the effect of AWD being particularly strong. During the entire growth period, the mean abundances of the AOA amoA, AOB amoA, and nifH genes were 2.9, 5.8, and 3.0 higher in the AWD treatment than in the CF treatment, respectively, and the activities of urease, protease, and ammonia oxidase were 1.1, 0.5, and 0.7 higher in the AWD treatment than in the CF treatment, respectively. The abundances of the nirS and nirK genes, and the activities of nitrate reductase and nitrite reductase were 73.6, 84.8, 10.3 and 36.5% lower in the AWD treatment than in the CF treatment, respectively. The abundances of the AOA amoA, AOB amoA, and nifH genes were significantly and positively correlated wi

关键词： rhizosphere aeration gene abundance enzyme activities soil microbial biomass carbon soil microbial nitrogen

Migration-Prevention Strategy to Fabricate Single-Atom Fe Implanted N-Doped Porous Carbons for Efficient Oxygen Reduction

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Research 2019年第1期2019卷 612-623页

作者： Dong-Li Meng chun-hui Chen Jun-Dong Yi Qiao Wu Jun Liang yuan-Biao Huang Rong Cao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of the Chinese Academy of Sciences Beijing 100049China

It is highly desired but challenging to achieve highly active single-atom Fe sites from iron-based metal-organic frameworks(MOFs)for efcient oxygen reduction reaction(ORR)due to the easy aggregation of iron species and formation of the inactive Fe-based particles during ***,a facile migration-prevention strategy is developed involving the incorporation of polyaniline(PANI)into the pores of iron porphyrinic-based MOF PCN-224(Fe)and followed by pyrolysis to obtain the single-atom Fe implanted N-doped porous carbons material PANI@PCN-224(Fe)-*** introduced PANI inside the pores of PCN-224(Fe)not only served as protective fences to prevent the aggregation of the iron species during thermal annealing,but also acted as nitrogen sources to increase the nitrogen content and form Fe-Nx-C active *** with the pristine PCN-224(Fe)derived carbonization sample containing Fe-based particles,the carbonaceous material PANI@PCN-224(Fe)-900 without inactive Fe-based particles exhibited superb ORR electrocatalytic activity with a more positive half-wave potential,signifcantly improved stability in both alkaline media,and more challenging acidic *** migration-prevention strategy provides a new way to fabricate atomically dispersed metal active sites via pyrolysis approach for promoting catalysis.

关键词： prevention pyrolysis Oxygen

Exploring the Feasibility of Machine Learning to Predict Risk Stratification Within 3 Months in Chest Pain Patients with Suspected NSTE-ACS

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Biomedical and Environmental Sciences 2023年第7期36卷 625-634页

作者： ZHENG Zhi Chang yuan Wei WANG Nian JIANG Bo MA chun Peng AI hui WANG Xiao NIE Shao Ping Cardiovascular Medicine Department Beijing Bo’ai HospitalChina Rehabilitation Research CenterCapital Medical UniversityBeijing 100068China Center for Coronary Artery Disease Beijing Anzhen HospitalCapital Medical UniversityBeijing 100029China Respiratory Medicine Department Beijing Friendship Hospital Affiliated of Capital Medical UniversityBeijing 100050China School of Computer Science and Engineering Beihang UniversityBeijing 100191China Department of Cardiology the First Hospital of QinhuangdaoHebei Medical UniversityQinhuangdao 066001HebeiChina

Objective We aimed to assess the feasibility and superiority of machine learning(ML)methods to predict the risk of Major Adverse Cardiovascular Events(MACEs)in chest pain patients with *** Enrolled chest pain patients were from two centers,Beijing Anzhen Emergency Chest Pain Center Beijing Bo’ai Hospital,China Rehabilitation Research *** classifiers were used to develop ML ***,Precision,Recall,F-Measure and AUC were used to assess the model performance and prediction effect compared with HEART risk scoring ***,ML model constructed by Naïve Bayes was employed to predict the occurrence of *** According to learning metrics,ML models constructed by different classifiers were superior over HEART(History,ECG,Age,Risk factors,&Troponin)scoring system when predicting acute myocardial infarction(AMI)and all-cause ***,according to ROC curves and AUC,ML model constructed by different classifiers performed better than HEART scoring system only in prediction for *** the five ML algorithms,Linear support vector machine(SVC),Naïve Bayes and Logistic regression classifiers stood out with all Accuracy,Precision,Recall and F-Measure from 0.8 to 1.0 for predicting any event,AMI,revascularization and all-cause death(***≤0.78),with AUC from 0.88 to 0.98 for predicting any event,AMI and revascularization(***≤0.85).ML model developed by Naïve Bayes predicted that suspected acute coronary syndrome(ACS),abnormal electrocardiogram(ECG),elevated hs-cTn I,sex and smoking were risk factors of *** Compared with HEART risk scoring system,the superiority of ML method was demonstrated when employing Linear SVC classifier,Naïve Bayes and *** method could be a promising method to predict MACEs in chest pain patients with NSTE-ACS.

关键词： Machine learning MACEs Chest pain Suspected NSTE-ACS

Specification and Verification of the Zab Protocol with TLA+

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Journal of Computer Science & Technology 2020年第6期35卷 1312-1323页

作者： Jia-Qi Yin hui-Biao Zhu yuan Fei Shanghai Key Laboratory of Trustworthy Computing East China Normal UniversityShanghai 200062China College of Information Mechanical and Electrical EngineeringShanghai Normal UniversityShanghai 200234China

ZooKeeper Atomic Broadcast (Zab) is an atomic broadcast protocol specially designed for ZooKeeper, which supports additional crash recovery. This protocol actually has been widely adopted by famous Internet companies, but there are few studies on the correctness and credibility of the Zab protocol, and thus we utilize formal methods to study the correctness. In this paper, Zab, Paxos and Raft are all analyzed and compared to help better understand the Zab protocol. Then we model the Zab protocol with TLA+ and verify three properties abstracted from the specification by the model checker TLC, including two liveness properties and one safety property. The final experimental results can prove that the design of the protocol conforms to the original requirements. This paper makes up for the analysis of formal methods in the Zab protocol.

关键词： Zab protocol TLA+ specification verification