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The Nonexistence of Sensitive Commutative Group Actions on Dendrites

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Acta Mathematica Sinica,English Series 2010年第10期26卷 1961-1968页

作者： En Hui SHI Bin Yong SUN li zhen zhou Mathematics and Science College Suzhou University Suzhou 215006 P. R. China Academy of Mathematics and Systems Science CAS Beijing 100190 P. R. China

In this paper, using the integral method observed by Mai Jiehua recently, we show that no dendrite admits a sensitive commutative group action.

关键词： Homeomorphism commutative group action sensitivity dendrite continuum

Source apportionment of PM_(2.5)using PMF combined online bulk and single-particle measurements:Contribution of fireworks and biomass burning

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Journal of Environmental Sciences 2024年第2期136卷 325-336页

作者： Yanjing Zhang Wenshuai li Lei li Mei li zhen zhou Jianzhen Yu Yang zhou Frontier Science Center for Deep Ocean Multispheres and Earth System(FDOMES)and Physical Oceanography Laboratory Ocean University of ChinaQingdaoShandong 266100China College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdaoShandong 266100China Institute of Atmospheric Environment Safety and Pollution Control Jinan UniversityGuangdong 510632China Institute of Environment Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Department of Chemistry Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Division of Environment The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina

Fireworks(FW)could significantly worsen air quality in short term during *** to similar tracers with biomass burning(BB),the fast and precise qualification of FW and BB is still *** this study,online bulk and single-particle measurements were combined to investigate the contributions of FW and BB to the overall mass concentrations of PM_(2.5)and specific chemical species by positive matrix factorization(PMF)during the Chinese New Year in Hong Kong in February *** combined information,fresh/aged FW(abundant ^(140)K_(2)NO_(3)^(+)and ^(213)K_(3)SO_(4)^(+)formed from ^(113)K_(2)Cl^(+)discharged by fresh FW)can be extracted from the fresh/aged BB sources,in addition to the Second Aerosol,Vehicles+Road Dust,and Sea Salt *** contributions of FW and BB were investigated during three high particle matter episodes influenced by the pollution transported from the Pearl River Delta *** fresh BB/FW contributed 39.2%and 19.6%to PM_(2.5)during the Lunar Chinese New Year ***,the contributions of aged FW/BB enhanced in the last two episodes due to the aging process,evidenced by high contributions from secondary ***,the fresh BB/FW showed more significant contributions to nitrate(35.1%and15.0%,respectively)compared with sulfate(25.1%and 5.9%,respectively)and OC(14.8%and11.1%,respectively)on *** comparison,the aged FW contributed more to sulfate(13.4%).Overall,combining online bulk and single-particle measurement data can combine both instruments’advantages and provide a new perspective for applying source apportionment of aerosols using PMF.

关键词： Source apportionment PMF Online bulk measurements Single particle analysis Fireworks Biomass burning

Upreguiation of human telomerase reverse transcriptase mRNA expression by in vitro transfection of hepatitis B virus X gene into human hepatocarcinoma and cholangiocarcinoma cells

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World Journal of Gastroenterology 2005年第36期11卷 5627-5632页

作者： zhen-liang Qu Sheng-Quan Zou Nai-Qiang Cui Xian-Zhong Wu Ming-Fang Qin Di Kong zhen-li zhou Department of surgery Tianjin Nankai Hospital Tianjin 300100 China Department of Surgery Tongji Hospital Wuhan430030 Hubei Province China

AIM： To study the changes of human telomerase reverse transcriptase （hTERT） mRNA expression in human hepatocarcinoma cell lines （HepG2） and cholangiocarcinoma cell lines （QBC939） after HBx gene transfection and to illustrate the significance of transcriptional regulation of hTERT gene by HBx gene in the carcinogenesis. METHODS： HepG2 and QBC939 cell lines were cultured and co-transfected with eukaryotic expression vector containing the HBx coding region and cloning vector containing enhanced green fluorescent protein （EGFP） coding sequence using lipid-mediated gene transduction technique. Thirty-six hours after transfection, EGFP expression in cells was used as the indicator of successful transfection. Flow cytometry was performed to determine the transfection efficiency. Cells were harvested and total RNA was extracted using TRIzol reagent. The expression of hTERT mRNA in HepG2 and QBC939 cell lines was assayed by reverse transcriptionpolymerase chain reaction. The expression of HBx protein in both cell lines was detected by immunocytochemical staining and Western blotting. RESULTS： Flow cytometry showed that the transfection efficiency was 46.4% in HepG2 cells and 29.6% in QBC939 cells for both HBx gene expression vector and blank vector. The expression of hTERT mRNA was meaningfully increased in HepG2 and QBC939 cell lines when transfected with HBx gene expression vector compared to those transfected with OPTI-MEM medium and blank vector. Immunocytochemical staining and Western blotting revealed HBx protein expression in HepG2 and QBC939 cells only when transfected with HBx gene. CONCLUSION： HBx gene transfection can upregulate the transcriptional expression of hTERT mRNA. The transactivation of hTERT gene by HBx gene is a newfound mechanism for pathogenesis of hepatocarcinomas and cholangiocarcinomas after HBV infection. 2005 The WJG Press and Elsevier Inc. All rights reserved

关键词： Hepatocholangiocarcinoma Human telomerasereverse transcriptase Gene expression Hepatitis B virus X protein

Flotation characteristics of Shenfu coal macerals

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Journal of Coal Science & Engineering(China) 2013年第3期19卷 381-386页

作者： Wei ZHAO zhen li An-Ning zhou Zhi-Yuan YANG College of Chemistry & Chemical Engineering Xi'an University of science and Technology Xi'an 710054 China

The flotation characteristics of Shenfu coal macerals was researched. Taking flotation recovery and enrichment of macerals as the evaluation objects, the influence of the agent dosage, pulp concentration, impeller speed and aeration rate on the separating effect was investigated. And the optimum process conditions of flotation were confirmed. The results show that the agent dosage, pulp concentration, impeller speed and aeration rate have a significant impact on flotation recovery and en- richment of macerals. The float recovery was 73.28% and enrichment ratio of vitrinite was 83.89% when CTAB dosage of 1.0 kg/t, pulp concentration of 100 g/L, impeller speed of 1 700 r/min and aeration rate of 0.25 m3/（m2·min） were used. The tailings yield was 60.30% and enrichment ratio of inertinite was 61.44% when CTAB dosage of 0.5 kg/t, pulp concentration of 100 g/L, impeller speed of I 700 r/min and aeration rate of 0.20 m3/（m2·min） were used.

关键词： Shenfu coal maceral flotation separation

Phasic study of intestinal homeostasis disruption in experimental intestinal obstruction

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World Journal of Gastroenterology 2014年第25期20卷 8130-8138页

作者： Xiang-Yang Yu Chang-lin Zou zhen-li zhou Tao Shan Dong-Hua li Nai-Qiang Cui Department of Gastrointestinal Surgery Nankai Hospital Graduate School of Tianjin Medical University Tianjin Institute of Acute Abdominal Diseases of Integrated Traditional Chinese and Western Medicine Department of Hepatopancreatobiliary Surgery Nankai Hospital

AIM: To investigate the phasic alteration of intestinal homeostasis in an experimental model of intestinal obstruction.

关键词： Intestinal obstruction Rabbit model Homeostasis disruption Intestinal epithelial cells Intestinal microorganisms Intestinal immune system

Enhancing flotation recovery of residual carbon from gasification waste by mixing hydrophobic powder with diesel as collector

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Particuology 2024年第6期89卷 211-217页

作者： Rui Han Ningning Zhang Anning zhou zhen li Jinzhou Qu Hong Wang College of Chemistry and Chemical Engineering Xi’an University of Science and TechnologyXi’anShaanxi 710054China

Coal gasification fine slag(CGFS)is a solid waste containing residual carbon and ash generated during the coal gasification process,and the separation of the two components is the essential way to realize its environmental pollution reduction and resource value *** flotation is the preferred method for separating CGFS,but there is a barrier of low carbon recovery in this process due to the extensive adsorption of collector by the well-developed pores on residual *** this study,a sufficiently simple yet innovative collector,a mixture of hydrophobic powder and diesel,was proposed in an attempt to break the *** experiments with common diesel and this novel collector were performed respectively,and FTIR,XPS,and SEM-EDX were employed to analyze the collector action *** results revealed that the novel collector could significantly improve the residual carbon recovery;test results demonstrated that the novel collector could increase the hydrophobic functional group content on the fine slag surface,and the hydrophobic powders in this novel collector mainly appeared at the pore openings of the flotation *** essence of the mechanism is that the hydrophobic powders play a dual role of blocking pores and providing adsorption sites,thus facilitating the spreading of diesel on the carbon surface and promoting its *** study can provide creative ideas for the efficient disposal of coal gasification waste.

关键词： Coal gasification fine slag Carbon recovery Collector Fotation Hydrophobic powder

Cooperative UAV search strategy based on DMPC-AACO algorithm in restricted communication scenarios

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Defence Technology（防务技术） 2024年第1期31卷 295-311页

作者： Shiyuan Chai zhen Yang Jichuan Huang Xiaoyang li Yiyang Zhao Deyun zhou School of Electronics and Information Northwestern Polytechnical UniversityXi'an 710072China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China The 93147th Unit of Chinese PLA Air Force Chengdu610091China

Improvement of integrated battlefield situational awareness in complex environments involving dynamic factors such as restricted communications and electromagnetic interference(EMI)has become a contentious research *** certain mission environments,due to the impact of many interference sources on real-time communication or mission requirements such as the need to implement communication regulations,the mission stages are represented as a dynamic combination of several communication-available and communication-unavailable ***,the data interaction between unmanned aerial vehicles(UAVs)can only be performed in specific communication-available *** cooperative search algorithms cannot handle such situations *** solve this problem,this study constructed a distributed model predictive control(DMPC)architecture for a collaborative control of UAVs and used the Voronoi diagram generation method to re-plan the search areas of all UAVs in real time to avoid repetition of search areas and UAV collisions while improving the search efficiency and safety *** attention mechanism ant-colony optimization(AACO)algorithm is proposed for UAV search-control decision *** search strategy is adaptively updated by introducing an attention mechanism for regular instruction information,a priori information,and emergent information of the mission to satisfy different search expectations to the maximum *** results show that the proposed algorithm achieves better search performance than traditional algorithms in restricted communication constraint scenarios.

关键词： Unmanned aerial vehicles(UAV) Cooperative search Restricted communication Mission planning DMPC-AACO

Co_(3)S_(4)-pyrolysis lotus fiber flexible textile as a hybrid electrocatalyst for overall water splitting

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Journal of Energy Chemistry 2024年第2期89卷 336-344,I0008页

作者： Qiulan zhou zhen liu Xuxu Wang Yaqian li Xin Qin lijuan Guo liwei zhou Weijian Xu Academician Workstation Changsha Medical UniversityChangsha 410219HunanChina College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082HunanChina College of Environmental Science and Engineering Hunan UniversityChangsha 410082HunanChina School of Basic Medicine Changsha Medical UniversityChangsha 410219HunanChina

Electrocatalytic overall water splitting(OWS),a pivotal approach in addressing the global energy crisis,aims to produce hydrogen and ***,most of the catalysts in powder form are adhesively bounding to the electrodes,resulting in catalyst detachment by bubble generation and other uncertain interference,and eventually reducing the OWS *** surmount this challenge,we synthesized a hybrid material of Co_(3)S_(4)-pyrolysis lotus fiber(labeled as Co_(3)S_(4)-p LF)textile by hydrothermal and hightemperature pyrolysis processes for electrocatalytic *** to the natural LF textile exposing the uniformly distributed functional groups(AOH,ANH_(2),etc.)to anchor Co_(3)S_(4)nanoparticles with hierarchical porous structure and outstanding hydrophily,the hybrid Co_(3)S_(4)-p LF catalyst shows low overpotentials at 10 m A cm^(-2)(η_(10,HER)=100 m Vη_(10,OER)=240 mV)alongside prolonged operational stability during electrocatalytic *** calculations reveal that the electron transfer from p LF to Co_(3)S_(4)in the hybrid Co_(3)S_(4)-p LF is beneficial to the electrocatalytic *** work will shed light on the development of nature-inspired carbon-based materials in hybrid electrocatalysts for OWS.

关键词： Overall water splitting Hybrid electrocatalyst Textile Lotus fiber Co_(3)S_(4)nanoparticles

Reevaluation by the CRISPR/Cas9 knockout approach revealed that multiple pluripotency-associated lncRNAs are dispensable for pluripotency maintenance while Snora73a/b is essential for pluripotency exit

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Science China(life Sciences) 2024年第10期67卷 2198-2212页

作者： zhen li Xuefei li Jingxia lin Yangming Wang Huiqing Cao Jiajian zhou Institute of Molecular Medicine College of Future TechnologyPeking UniversityBeijing 100871China Dermatology Hospital Southern Medical UniversityGuangzhou 510091China Beijing Advanced Center of RNA Biology(BEACON) Peking UniversityBeijing 100871China

Many long noncoding RNAs(lncRNAs)have been identified through siRNA-based screening as essential regulators of embryonic stem cell(ESC)***,the biological and molecular functions of most lncRNAs remain ***,we employed CRISPR/Cas9-mediated knockout technology to explore the functions of 8 lncRNAs previously reported to promote pluripotency in mouse ***,all of these lncRNAs were dispensable for pluripotency maintenance and proliferation in mouse ESCs when disrupted individually or in ***-cell transcriptomic analysis also showed that the knockout of these lncRNAs has a minimal impact on pluripotency gene expression and cell *** further showed that several small hairpin RNAs(shRNAs)previously used to knock down lncRNAs caused the downregulation of pluripotency genes in the corresponding lncRNA-knockout ESCs,indicating that off-target effects likely responsible for the pluripotency defects caused by these ***,linc1343-knockout and linc1343-knockdown ESCs failed to form cystic structures and exhibited high expression of pluripotency genes during embryoid body(EB)*** reintroducing RNA products generated from the linc1343 locus,we found that two snoRNAs,Snora73a and Snora73b,but not lncRNAs,could rescue pluripotency silencing defects during EB differentiation of linc1343 knockout *** results suggest that the 8 previously annotated pluripotency-regulating lncRNAs have no overt functions in conventional ESC culture;however,we identified snoRNA products derived from an annotated lncRNA locus as essential regulators for silencing pluripotency genes.

关键词： long noncoding RNAs embryonic stem cells CRISPR/Cas9 snoRNAs stem cell differentiation

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