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Prescribed Performance Tracking Control of Time-Delay Nonlinear Systems With Output Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1557-1565页

作者： jin-xi Zhang Kai-Di Xu Qing-Guo Wang IEEE the State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China Institute of Artificial Intelligence and Future Networks Beijing Normal UniversityZhuhai 519087 Guangdong Key Laboratory of Artificial Intelligence and Multi-Modal Data Processing Beijing Normal University-Hong Kong Baptist University United International CollegeZhuhai 519087

The problem of prescribed performance tracking control for unknown time-delay nonlinear systems subject to output constraints is dealt with in this paper. In contrast with related works, only the most fundamental requirements, i.e., boundedness and the local Lipschitz condition, are assumed for the allowable time delays. Moreover, we focus on the case where the reference is unknown beforehand, which renders the standard prescribed performance control designs under output constraints infeasible. To conquer these challenges, a novel robust prescribed performance control approach is put forward in this paper.Herein, a reverse tuning function is skillfully constructed and automatically generates a performance envelop for the tracking error. In addition, a unified performance analysis framework based on proof by contradiction and the barrier function is established to reveal the inherent robustness of the control system against the time delays. It turns out that the system output tracks the reference with a preassigned settling time and good accuracy,without constraint violations. A comparative simulation on a two-stage chemical reactor is carried out to illustrate the above theoretical findings.

关键词： Nonlinear systems output constraints prescribed performance reference tracking time delays

Precisely Control Relationship between Sulfur Vacancy and H Absorption for Boosting Hydrogen Evolution Reaction

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Nano-Micro Letters 2024年第4期16卷 14-24页

作者： jing jin xinyao Wang Yang Hu Zhuang Zhang Hongbo Liu Jie Yin Pinxian xi College of Chemistry and Chemical Engineering Frontiers Science Center for Rare IsotopesState Key Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou 730000People’s Republic of China

Ef fective and robust catalyst is the core of water splitting to produce hydrogen.Here, we report an anionic etching method to tailor the sulfur vacancy(VS) of NiS_(2) to further enhance the electrocatalytic performance for hydrogen evolution reaction(HER). With the VS concentration change from 2.4% to 8.5%, the H* adsorption strength on S sites changed and NiS_(2)-VS 5.9% shows the most optimized H* adsorption for HER with an ultralow onset potential(68 m V) and has long-term stability for 100 h in 1 M KOH media. In situ attenuated-total-reflection Fourier transform infrared spectroscopy(ATR-FTIRS) measurements are usually used to monitor the adsorption of intermediates. The S-H* peak of the Ni S_(2)-VS 5.9% appears at a very low voltage, which is favorable for the HER in alkaline media. Density functional theory calculations also demonstrate the Ni S_(2)-VS 5.9% has the optimal |ΔG^(H*)| of 0.17 e V. This work offers a simple and promising pathway to enhance catalytic activity via precise vacancies strategy.

关键词： Hydrogen evolution reaction S vacancies Nanosheet H Adsorption

Effect of Sonic hedgehog gene-modified bone marrow mesenchymal stem cells on graft-induced retinal gliosis and retinal ganglion cells survival in diabetic mice

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 34-41页

作者： Tong Wang Hai-Chun Li jin Ma xi-Ling Yu State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangdong Provincial Key Laboratory of Ophthalmology and Visual ScienceGuangzhou 510060Guangdong ProvinceChina

AIM:To investigate the effects of Sonic hedgehog(Shh)gene-modified bone marrow mesenchymal stem cells(MSCs)on graft-induced retinal gliosis and retinal ganglion cells(RGCs)survival in diabetic mice.METHODS:Bone marrow-derived MSCs were genetically modified with the Shh gene to generate a stably transfected cell line of Shh-modified MSCs(MSC-Shh).Intravitreal injections of MSC-Shh and green fluorescent protein-modified MSCs(MSC-Gfp;control)were administered in diabetic mice.After 4wk,the effects of MSC-Shh on retinal gliosis were evaluated using fundus photography,and markers of gliosis were examined by immunofluorescence and Western blotting.The neurotrophic factors expression and RGCs survival in the host retina were evaluated using Western blotting and immunofluorescence.The mechanisms underlying the effects of MSC-Shh was investigated.RESULTS:A significant reduction of proliferative vitreoretinopathy(PVR)was observed after intravitreal injection of MSC-Shh compared to MSC-Gfp.Significant downregulation of glial fibrillary acidic protein(GFAP)was demonstrated in the host retina after MSC-Shh administration compared to MSC-Gfp.The extracellular signal-regulated kinase 1/2(ERK1/2),protein kinase B(AKT)and phosphatidylin-ositol-3-kinase(PI3K)pathways were significantly downregulated after MSC-Shh administration compared to MSC-Gfp.Brain-derived neurotrophic factor(BDNF)and ciliary neurotrophic factor(CNTF)levels were significantly increased in the host retina,and RGCs loss was significantly prevented after MSC-Shh administration.CONCLUSION:MSC-Shh administration reduces graft-induced reactive gliosis following intravitreal injection in diabetic mice.The ERK1/2,AKT and PI3K pathways are involved in this process.MSC-Shh also increases the levels of neurotrophic factors in the host retina and promoted RGCs survival in diabetic mice.

关键词： mesenchymal stem cells Sonic hedgehog signaling reactive gliosis diabetic retinopathy retinal ganglion cells

Decoding the Cellular Trafficking of Prion-like Proteins in Neurodegenerative Diseases

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Neuroscience Bulletin 2024年第2期40卷 241-254页

作者： Chenjun Hu Yiqun Yan Yanhong jin Jun Yang Yongmei xi Zhen Zhong Department of Neurology of the Second Afliated Hospital and Department of Human Anatomy Histology and EmbryologyZhejiang University School of MedicineHangzhou 310058China Department of Physiology and Department of Cardiology of the Second Afliated Hospital Zhejiang University School of MedicineHangzhou 310058China Division of Human Reproduction and Developmental Genetics Women’s Hospital and Institute of GeneticsZhejiang University School of MedicineHangzhou 310006China

The accumulation and spread of prion-like proteins is a key feature of neurodegenerative diseases(NDs)such as Alzheimer’s disease,Parkinson's disease,or Amyotrophic Lateral Sclerosis.In a process known as‘seeding’,prion-like proteins such as amyloid beta,microtubule-associated protein tau,α-synuclein,silence superoxide dismutase 1,or transactive response DNA-binding protein 43 kDa,propagate their misfolded conformations by transforming their respective soluble monomers into fibrils.Cellular and molecular evidence of prion-like propagation in NDs,the clinical relevance of their‘seeding’capacities,and their levels of contribution towards disease progression have been intensively studied over recent years.This review unpacks the cyclic prion-like propagation in cells including factors of aggregate internalization,endo-lysosomal leaking,aggregate degradation,and secretion.Debates on the importance of the role of prion-like protein aggregates in NDs,whether causal or consequent,are also discussed.Applications lead to a greater understanding of ND pathogenesis and increased potential for therapeutic strategies.

关键词： Neurodegenerative diseases Prion-like propagation Seeding Endocytosis Endolyosomal leaking Degradation

SERPINH1 promoted the proliferation and metastasis of colorectal cancer by activating PI3K/Akt/mTOR signaling pathway

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1890-1907页

作者： xiao-Sheng jin Lu-xi Chen Ting-Ting Ji Rong-Zhou Li Department of Gastroenterology The Third Affiliated Hospital of Wenzhou Medical UniversityRuian 325000Zhejiang ProvinceChina

BACKGROUND Serpin peptidase inhibitor clade H member 1(SERPINH1)was initially recognized as an oncogene implicated in various human malignancies.Nevertheless,the clinical relevance and functional implications of SERPINH1 in colorectal cancer(CRC)remain largely elusive.AIM To investigate the effects of SERPINH1 on CRC cells and its specific mechanism.METHODS Quantitative real-time polymerase chain reaction,western blotting analysis,The Cancer Genome Atlas data mining and immunohistochemistry were employed to examine SERPINH1 expression in CRC cell lines and tissues.A series of in-vitro assays were performed to demonstrate the function of SERPINH1 and its possible mechanisms in CRC.RESULTS SERPINH1 demonstrated elevated expression levels in both CRC cells and tissues,manifested at both mRNA and protein tiers.Elevated SERPINH1 levels correlated closely with advanced T stage,lymph node involvement,and distant metastasis,exhibiting a significant association with poorer overall survival among CRC patients.Subsequent investigations unveiled that SERPINH1 overexpression notably bolstered CRC cell proliferation,invasion,and migration in vitro,while conversely,SERPINH1 knockdown elicited the opposite effects.Gene set enrichment analysis underscored a correlation between SERPINH1 upregulation and genes associated with cell cycle regulation.Our findings underscored the capacity of heightened SERPINH1 levels to expedite G1/S phase cell cycle progression via phosphatidylinositol 3-kinase/AKT/mechanistic target of rapamycin pathway activation,thereby facilitating CRC cell invasion and migration.CONCLUSION These findings imply a crucial involvement of SERPINH1 in the advancement and escalation of CRC,potentially positioning it as a novel candidate for prognostic assessment and therapeutic intervention in CRC management.

关键词： Serpin peptidase inhibitor clade H member 1 Colorectal cancer Proliferation Cell cycle Phosphatidylinositol 3-kinase/AKT/mechanistic target of rapamycin

Static recrystallization behaviors and mechanisms of 7Mo super-austenitic stainless steel with undissolved sigma precipitates during double-stage hot deformation

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Journal of Iron and Steel Research(International) 2024年第2期31卷 475-487页

作者： Shi-guang Xu jin-shan He Run-ze Zhang Fu-cheng Zhang xi-tao Wang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004HebeiChina Shandong Provincial Key Laboratory for High Strength Lightweight Metallic Materials Advanced Materials InstituteQilu University of Technology(Shandong Academy of Science)Jinan250353ShandongChina

Static recrystallization(SRX)behaviors and corresponding recrystallization mechanisms of 7Mo super-austenitic stainless steel were studied under different deformation conditions.The order of influence of deformation parameters on static recrystallization behaviors,from high to low,is followed by temperature,first-stage strain and strain rate.Meanwhile,the effect of holding time on static recrystallization behaviors is significantly controlled by temperature.In addition,with the increase in temperature from 1000 to 1200°C,the static recrystallization mechanism evolves from discontinuous static recrystallization and continuous static recrystallization(cSRX)to metadynamic recrystallization and cSRX,and finally to cSRX.The cSRX exists at all temperatures.This is because high stacking fault energy(56 mJ m−2)promotes the movement of dislocations,making the deformation mechanism of this steel is dominated by planar slip of dislocation.Large undissolved sigma precipitates promote static recrystallization through particle-stimulated nucleation.However,small strain-induced precipitates at grain boundaries hinder the nucleation of conventional SRX and the growth of recrystallized grains,while the hindering effect decreases with the increase in temperature.

关键词： 7Mo super-austenitic stainless steel Double-stage hot deformation Conventional static recrystallization Metadynamic recrystallization Strain-induced precipitation

Experimental investigation on using CO_(2)/H_(2)O emulsion with high water cut in enhanced oil recovery

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Petroleum Science 2024年第2期21卷 974-986页

作者： xi-Dao Wu Peng xiao Bei Liu Guang-jin Chen Jian-Hua Pang State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Ocean Intelligence Technology Center Shenzhen Institute of Guangdong Ocean UniversityShenzhen518120GuangdongChina

CO_(2) emulsions used for EOR have received a lot of interest because of its good performance on CO_(2)mobility reduction.However,most of them have been focusing on the high quality CO_(2) emulsion(high CO_(2) fraction),while CO_(2) emulsion with high water cut has been rarely researched.In this paper,we carried out a comprehensive experimental study of using high water cut CO_(2)/H_(2)O emulsion for enhancing oil recovery.Firstly,a nonionic surfactant,alkyl glycosides(APG),was selected to stabilize CO_(2)/H_(2)O emulsion,and the corresponding morphology and stability were evaluated with a transparent PVT cell.Subsequently,plugging capacity and apparent viscosity of CO_(2)/H_(2)O emulsion were measured systematically by a sand pack displacement apparatus connected with a 1.95-m long capillary tube.Furthermore,a high water cut(40 vol%) CO_(2)/H_(2)O emulsion was selected for flooding experiments in a long sand pack and a core sample,and the oil recovery,the rate of oil recovery,and the pressure gradients were analyzed.The results indicated that APG had a good performance on emulsifying and stabilizing CO_(2) emulsion.An inversion from H_(2)O/CO_(2) emulsion to CO_(2)/H_(2)O emulsion with the increase in water cut was confirmed.CO_(2)/H_(2)O emulsions with lower water cuts presented higher apparent viscosity,while the optimal plugging capacity of CO_(2)/H_(2)O emulsion occurred at a certain water cut.Eventually,the displacement using CO_(2)/H_(2)O emulsion provided 18.98% and 13.36% additional oil recovery than that using pure CO_(2) in long sand pack and core tests,respectively.This work may provide guidelines for EOR using CO_(2) emulsions with high water cut.

关键词： CO_(2)/H_(2)O emulsion High water cut CO_(2)mobility control Enhanced oil recovery

Calcification-associated molecular traits and therapeutic strategies in hormone receptor-positive HER2-negative breast cancer

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Cancer Biology & Medicine 2024年第5期21卷 400-415页

作者： Yuwei Li Yuzheng Xu Caijin Lin xi jin Ding Ma Zhiming Shao Department of Breast Surgery Fudan University Shanghai Cancer Center Key Laboratory of Breast Cancer in Shanghai Fudan University Shanghai Cancer Center Department of Oncology Shanghai Medical College Fudan University

Objective: Mammographic calcifications are a common feature of breast cancer, but their molecular characteristics and treatment implications in hormone receptor-positive(HR+)/human epidermal growth factor receptor 2-negative(HER2-) breast cancer remain unclear.Methods: We retrospectively collected mammography records of an HR+/HER2-breast cancer cohort(n = 316) with matched clinicopathological, genomic, transcriptomic, and metabolomic data. On the basis of mammographic images, we grouped tumors by calcification status into calcification-negative tumors, tumors with probably benign calcifications, tumors with calcification of lowmoderate suspicion for maligancy and tumors with calcification of high suspicion for maligancy. We then explored the molecular characteristics associated with each calcification status across multiple dimensions.Results: Among the different statuses, tumors with probably benign calcifications exhibited elevated hormone receptor immunohistochemical staining scores, estrogen receptor(ER) pathway activation, lipid metabolism, and sensitivity to endocrine therapy. Tumors with calcifications of high suspicion for malignancy had relatively larger tumor sizes, elevated lymph node metastasis incidence, Ki-67 staining scores, genomic instability, cell cycle pathway activation, and may benefit from cyclin-dependent kinase 4 and 6(CDK4/6) inhibitors.Conclusions: Our research established links between tumor calcifications and molecular features, thus proposing potential precision treatment strategies for HR+/HER2-breast cancer.

关键词： HR+/HER2-breast cancer mammographic calcifications molecular features precision treatment ENDOCRINE THERAPY SENSITIVITY REPAIR

Fe/S oxidation-coupled arsenic speciation transformation mediated by AMD enrichment culture under different pH conditions

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Journal of Environmental Sciences 2024年第3期137卷 681-700页

作者： Yu-hang Zhou Wei-xi Huang Zhen-yuan Nie Hong-chang Liu Yue Liu Can Wang jin-lan xia Wen-sheng Shu Key Lab of Biometallurgy of Ministry of Education of China School of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China School of Life Sciences South China Normal UniversityGuangzhou 510631China

Arsenic(As)speciation transformation in acid mine drainage(AMD)is comprehensively affected by biological and abiotic factors,such as microbially mediated Fe/S redox reactions and changes in environmental conditions(pH and oxidation-reduction potential).However,their combined impacts on arsenic speciation transformation remain poorly studied.Therefore,we explored arsenic transformation and immobilization during pyrite dissolution mediated by AMD enrichment culture under different acidic pH conditions.The results for incubation and mineralogical transformation of solid residues show that in the presence of AMD enrichment culture,pH 2.0,2.5,and 3.0 are more conducive to the formation of jarosites and ferric arsenate,which could immobilize high quantities of dissolved arsenic by adsorption and coprecipitation.The pH conditions significantly affect the initial adsorption of microbial cells to the minerals and the evolution of microbial community structure,further infuencing the biodissolution of pyrite and the release and oxidation process of Fe/S.The results of Fe/S/As speciation transformation of the solid residues show that the transformation of Fe,S,and As in solution is mainly regulated by pH and potential values,which imposed significantly different effects on the formation of secondary minerals and thus arsenic oxidation and immobilization.The above results indicated that arsenic transformation is closely related to the Fe/S oxidation associated with pyrite bio-oxidation,and this correlation is critically regulated by the pH conditions of the system.

关键词： Acid mine drainage(AMD) pH conditions Fe/S/As speciation transformation Microbial community structure