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A calibration and compensation method for an industrial robot with high accuracy harmonic reducers

Science China(Technological Sciences) 2024年第3期67卷 725-739页

作者： ZHAO YiYang liu xun CAO JiaBin liu JinYu XU Yan YAN WeiXin School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China College of Computer and Control Engineering Northeast Forestry UniversityHarbin 150040China

Industrial serial robots need high stiffness to keep absolute pose accuracy and meet the requirements in practical applications. However, the weak stiffness feature of robot joints and the payloads affected on robot end-effector, which will also increase the pose error of robot. Especially, the existing calibration methods often consider under no-payload condition without discussing the payload state. In this paper, we report a new industrial serial robot composed by a new harmonic reducer: Model-Y, based on high accuracy and high stiffness, and a kinematic parameter calibration algorithm which is based on a harmonic reducer forcedeformation model. To decrease the accuracy effects of payload, an iterative calibration method for kinematic parameters with payload situation was proposed. Simulation and experiments are conducted to verify the effectiveness of the proposed calibration method using the self-developed industrial serial robot. The results show a remarkably improved accuracy in absolute position and orientation with the robot's payload range. The position mean error has 70% decreased to 0.1 mm and the orientation mean error diminished to less than 0.01° after calibration with compensation. Additionally, online linear and circular tests are carried out to evaluate the position error of the robot during large-scale spatial and low-speed continuous movement. The accuracy is consistent with the previous calibration results, indicating the effectiveness and advantages of the proposed strategy in this article.

关键词： industrial serial robot Model-Y harmonic calibration stiffness model online compensation

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Assessment of tree-ring mercury radial translocation and age effect in Masson pine:Implications for historical atmospheric mercury reconstruction

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Journal of Environmental Sciences 2024年第4期138卷 266-276页

作者： Xu liu xun Wang Dingyong Wang College of Resources and Environment Southwest UniversityChongqing 400715China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

The tree ring has been regarded as an emerging archive to reconstruct historical atmospheric mercury(Hg)trends,but with the large knowledge gaps in the reliability.In this study,we comprehensively evaluated the Hg source,radial translocation and age effect of Masson pine(Pinus massoniana)tree ring at Mt.Jinyun in Chongqing,to assess the suitability of such tree ring as the archive of atmospheric Hg.Results showed that distinct variabilities among Masson pine tree-ring Hg concentration profiles.The Hg concentration significantly increased along with stem height(P<0.05),indicating the Hg in tree rings mainly derived from foliage uptake atmospheric Hg.We found a distinct age effect that the tree ring of young trees had the higher Hg concentration.Besides,we used the advection-diffusion model to demonstrate how Hg concentration shifted by the advection or/and diffusion in tree rings.The modeling results showed that the advection induced radial translocation during the young growth period of tree was a plausible mechanism to result in the tree-ring Hg record largely different from the trend of anthropogenic Hg emissions in Chongqing.We finally suggest that in further Hg dendrochemistry,better discarding the tree-ring Hg profile of the young growth period to reduce impacts of the radial translocation and age effect.

关键词： Masson pine Tree-ring mercury Radial translocation Tree age effect

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Thymoquinone affects hypoxia-inducible factor-1αexpression in pancreatic cancer cells via HSP90 and PI3K/AKT/mTOR pathways

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World Journal of Gastroenterology 2024年第21期30卷 2793-2816页

作者： Zhan-Xue Zhao Shuai Li Lin-xun liu Department of General Surgery Qinghai Provincial People's HospitalXining 810007Qinghai ProvinceChina Department of Clinical Pharmacy The Affiliated Hospital of Qinghai UniversityXining 810001Qinghai ProvinceChina

BACKGROUND Pancreatic cancer(PC)is associated with some of the worst prognoses of all major cancers.Thymoquinone(TQ)has a long history in traditional medical practice and is known for its anti-cancer,anti-inflammatory,anti-fibrosis and antioxidant pharmacological activities.Recent studies on hypoxia-inducible factor-1α(HIF-1α)and PC have shown that HIF-1αaffects the occurrence and development of PC in many aspects.In addition,TQ could inhibit the development of renal cancer by decreasing the expression of HIF-1α.Therefore,we speculate whether TQ affects HIF-1αexpression in PC cells and explore the mechanism.AIM To elucidate the effect of TQ in PC cells and the regulatory mechanism of HIF-1αexpression.METHODS Cell counting kit-8 assay,Transwell assay and flow cytometry were performed to detect the effects of TQ on the proliferative activity,migration and invasion ability and apoptosis of PANC-1 cells and normal pancreatic duct epithelial(hTERTHPNE)cells.Quantitative real-time polymerase chain reaction and western blot assay were performed to detect the expression of HIF-1αmRNA and protein in PC cells.The effects of TQ on the HIF-1αprotein initial expression pathway and ubiquitination degradation in PANC-1 cells were examined by western blot assay and co-immunoprecipitation.RESULTS TQ significantly inhibited proliferative activity,migration,and invasion ability and promoted apoptosis of PANC-1 cells;however,no significant effects on hTERT-HPNE cells were observed.TQ significantly reduced the mRNA and protein expression levels of HIF-1αin PANC-1,AsPC-1,and BxPC-3 cells.TQ significantly inhibited the expression of the HIF-1αinitial expression pathway(PI3K/AKT/mTOR)related proteins,and promoted the ubiquitination degradation of the HIF-1αprotein in PANC-1 cells.TQ had no effect on the hydroxylation and von Hippel Lindau protein mediated ubiquitination degradation of the HIF-1αprotein but affected the stability of the HIF-1αprotein by inhibiting the interaction between HIF-1αand HSP90,thus promoting its ubiquitination

关键词： Thymoquinone Pancreatic cancer Hypoxia-inducible factor-1α PI3K/AKT/mTOR HSP90

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Sorl1 knockout inhibits expression of brain-derived neurotrophic factor:involvement in the development of late-onset Alzheimer's disease

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Neural Regeneration Research 2024年第7期19卷 1602-1607页

作者： Mingri Zhao xun Chen Jiangfeng liu Yanjin Feng Chen Wang Ting Xu Wanxi liu Xionghao liu Mujun liu Deren Hou Department of Neurology The Third Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina Center for Medical Genetics&Hunan Key Laboratory of Medical Genetics School of Life SciencesCentral South UniversityChangshaHunan ProvinceChina Department of Cell Biology School of Life SciencesCentral South UniversityChangshaHunan ProvinceChina

Sortilin-related receptor 1(SORL1)is a critical gene associated with late-onset Alzheimer’s disease.SORL1 contributes to the development and progression of this neurodegenerative condition by affecting the transport and metabolism of intracellularβ-amyloid precursor protein.To better understand the underlying mechanisms of SORL1 in the pathogenesis of late-onset Alzheimer s disease,in this study,we established a mouse model of SorI1 gene knockout using cluste red regularly inters paced short palindro mic repeats-associated protein 9 technology.We found that Sorl1-knocko ut mice displayed deficits in learning and memory.Furthermore,the expression of brain-derived neurotrophic factor was significantly downregulated in the hippocampus and co rtex,and amyloidβ-protein deposits were observed in the brains of 5orl1-knockout mice.In vitro,hippocampal neuronal cell synapses from homozygous Sorl1-knockout mice were impaired.The expression of synaptic proteins,including Drebrin and NR2B,was significantly reduced,and also their colocalization.Additionally,by knocking out the Sorl1 gene in N2a cells,we found that expression of the N-methyl-D-aspartate receptor,NR2B,and cyclic adenosine monophosphate-response element binding protein was also inhibited.These findings suggest that SORL1 participates in the pathogenesis of late-onset Alzheimer s disease by regulating the N-methyl-D-aspartate receptor NR2B/cyclic adenosine monophosphate-response element binding protein signaling axis.

关键词： brain-derived neurotrophic factor late-onset Alzheimer’s disease N-methyl-D-aspartate receptor sortilin-related receptor 1 synapse

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Correlation between the gut microbiome and neurodegenerative diseases:a review of metagenomics evidence

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Neural Regeneration Research 2024年第4期19卷 833-845页

作者： Xiaoyan liu Yi liu Junlin liu Hantao Zhang Chaofan Shan Yinglu Guo xun Gong Mengmeng Cui Xiubin Li Min Tang School of Life Sciences Jiangsu University Institute of Animal Husbandry Jiangsu Academy of Agricultural Sciences Department of Rheumatology&Immunology Affiliated Hospital of Jiangsu University Department of Neurology The Second Affiliated Hospital of Shandong First Medical University

A growing body of evidence suggests that the gut microbiota contributes to the development of neurodegenerative diseases via the microbiota-gut-brain axis.As a contributing factor,microbiota dysbiosis always occurs in pathological changes of neurodegenerative diseases,such as Alzheimer’s disease,Parkinson’s disease,and amyotrophic lateral sclerosis.High-throughput sequencing technology has helped to reveal that the bidirectional communication between the central nervous system and the enteric nervous system is facilitated by the microbiota’s diverse microorganisms,and for both neuroimmune and neuroendocrine systems.Here,we summarize the bioinformatics analysis and wet-biology validation for the gut metagenomics in neurodegenerative diseases,with an emphasis on multi-omics studies and the gut virome.The pathogen-associated signaling biomarkers for identifying brain disorders and potential therapeutic targets are also elucidated.Finally,we discuss the role of diet,prebiotics,probiotics,postbiotics and exercise interventions in remodeling the microbiome and reducing the symptoms of neurodegenerative diseases.

关键词： biomarker diet pattern gut microbiota gut-brain axis metagenomics mitochondrial dysfunction multi-omics neurodegenerative disease neuroinflammation probiotic

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Eco-evolutionary evidence for the global diversity pattern of Cycas(Cycadaceae)

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Journal of Integrative Plant Biology 2024年第6期66卷 1170-1191页

作者： Jian liu Anders J.Lindstrom Yiqing Gong Shanshan Dong Yusheng(Chris) liu Shouzhou Zhang xun Gong CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences Department of Economic Plants and Biotechnology Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of BotanyChinese Academy of Sciences University of Chinese Academy of Sciences Global Biodiversity Conservancy Key Laboratory of Southern Subtropical Plant Diversity Fairy Lake Botanical Garden Shenzhen & Chinese Academy of Sciences Department of Earth and Environmental Sciences Indiana University-Indianapolis

The evolution of the latitudinal diversity gradient(LDG), characterized by a peak in diversity toward the tropics, has captured significant attention in evolutionary biology and ecology.However, the inverse LDG(i-LDG) mechanism,wherein species richness increases toward the poles, remains inadequately explored. Cycads are among one of the oldest lineages of extant seed plants and have undergone extensive diversification in the tropics. Intriguingly, the extant cycad abundance exhibits an i-LDG pattern, and the underlying causes for this phenomenon remain largely elusive. Here,using 1,843 nuclear genes from a nearly complete sampling, we conducted comprehensive phylogenomic analyses to establish a robust species-level phylogeny for Cycas, the largest genus within cycads. We then reconstructed the spatial-temporal dynamics and integrated global environmental data to evaluate the roles of species ages, diversification rates,contemporary environment, and conservatism to ancestral niches in shaping the i-LDG pattern. We found Cycas experienced decreased diversification rates, coupled with the cooling temperature since its origin in the Eocene from continental Asia. Different regions have distinctively contributed to the formation of i-LDG for Cycas, with the northern hemisphere acting as evolutionary museums and the southern hemisphere serving as cradles. Moreover, water-related climate variables,specifically precipitation seasonality and potential evapotranspiration, were identified as paramount factors constraining Cycas species richness in the rainforest biome near the equator. Notably, the adherence to ancestral monsoonal climates emerges as a critical factor in sustaining the diversity pattern. This study underscores the imperative of integrating both evolutionary and ecological approaches to comprehensively unravel the mechanisms underpinning global biodiversity patterns.

关键词： cycads latitudinal diversity gradient niche conservatism spatiotemporal diversification species richness

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Efficacy and safety of remimazolam in bronchoscopic sedation:A meta-analysis

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World Journal of Clinical Cases 2024年第6期12卷 1120-1129页

作者： Ying Zhou Cheng Zhao Yi-xun Tang Ji-Tong liu Department of Anesthesiology The First Affiliated Hospital of Hunan Normal University(Hunan Provincial People’s Hospital)Changsha 410005Hunan ProvinceChina Department of Anesthesiology Zhangjiajie People's HospitalZhangjiajie 427000Hunan ProvinceChina

BACKGROUND Remimazolam is a new benzodiazepine used for procedural sedation and general anesthesia.Several studies have used remimazolam for bendable bronchoscopy.AIM To assess the safety and efficacy of remimazolam for sedation in patients undergoing bendable bronchoscopy by performing a meta-analysis of randomized controlled trials(RCTs).METHODS We searched the EMBASE,PubMed,Cochrane Library,and Web of Science databases for RCTs on bendable bronchoscopic procedural sedation with remimazolam vs conventional sedatives(CS).RESULTS Five studies with 1080 cases were included.Remimazolam had the same sedation success rate compared with CS[relative risk(RR):1.35,95%CI:0.60-3.05,P=0.474,I2=99.6%].However,remimazolam was associated with a lower incidence of hypotension(RR:0.61;95%CI:0.40-0.95,P=0.027;I2=65.1%)and a lower incidence of respiratory depression(RR:0.50,95%CI:0.33-0.77,P=0.002,I2=42.3%).A subgroup analysis showed a higher success rate of sedation with remimazolam than midazolam(RR:2.45,95%CI:1.76-3.42,P<0.001).Compared with propofol,the incidence of hypotension(RR:0.45,95%CI:0.32-0.64,P<0.001,I2=0.0%),respiratory depression(RR:0.48,95%CI:0.30-0.76,P=0.002,I2=78.4%),hypoxemia(RR:0.36,95%CI:0.15-0.87,P=0.023),and injection pain(RR:0.04,95%CI:0.01-0.28,P=0.001)were lower.CONCLUSION Remimazolam is safe and effective during bronchoscopy.The sedation success rate was similar to that in the CS group.However,remimazolam has a higher safety profile,with fewer inhibitory effects on respiration and circulation.

关键词： Remimazolam Bronchoscopy Procedural sedation Meta-analysis

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Safety and efficacy comparison of remimazolam and propofol for intravenous anesthesia during gastroenteroscopic surgery of older patients:A meta-analysis

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World Journal of Clinical Cases 2024年第7期12卷 1272-1283页

作者： Fang-Zhuo Li Cheng Zhao Yi-xun Tang Ji-Tong liu Department of Anesthesiology The First Affiliated Hospital of Hunan Normal University(Hunan Provincial People’s Hospital)Changsha 410005Hunan ProvinceChina Department of Anesthesiology Zhangjiajie People's HospitalZhangjiajie 427000Hunan ProvinceChina

BACKGROUND Remimazolam is characterized by rapid action and inactive metabolites.It is used as the general anesthetic for many clinical surgeries.In this study,we performed a meta-analysis to evaluate whether remimazolam is superior to propofol for gastroenteroscopy in older patients.AIM To compare the adverse events and efficacy of remimazolam and propofol during gastroenteroscopy in older adults.METHODS The PubMed,Web of Science,the Cochrane Library databases were queried for the relevant key words"remimazolam,""and propofol,""and gastrointestinal endoscopy or gastroscopy."The search scope was"Title and Abstract,"and the search was limited to human studies and publications in English.Seven studies wherein remimazolam and propofol were compared were included for the metaanalysis.RESULTS We selected seven randomized controlled trials involving 1445 cases for the analysis.Remimazolam reduced the hypotension(relative risk,RR=0.44,95%CI:0.29-0.66,P=0.000),respiratory depression(RR=0.46,95%CI:0.30-0.70,P=0.000),injection pain(RR=0.12,95%CI:0.05-0.25,P=0.000),bradycardia(RR=0.37,95%CI:0.24-0.58,P=0.000),and time to discharge[weighted mean difference(WMD)=-0.58,95%CI:-0.97 to-0.18,P=0.005],compared to those after propofol administration.No obvious differences were observed for postoperative nausea and vomiting(RR=1.09,95%CI:0.97-1.24,P=0.151),dizziness(RR=0.77,95%CI:0.43-1.36,P=0.361),successful sedation rate(RR=0.96,95%CI:0.93-1.00,P=0.083),or the time to become fully alert(WMD=0.00,95%CI:-1.08-1.08,P=0.998).CONCLUSION Remimazolam appears to be safer than propofol for gastroenteroscopy in older adults.However,further studies are required to confirm these findings.

关键词： Remimazolam Propofol Gastroenteroscopy Anesthesia Older adults Sedation Adverse events

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Real-time identification of multiple nanoclusters with a protein nanopore in single-cluster level

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Nano Research 2024年第1期17卷 262-269页

作者： Ling Zhang Peilei He Huang Chen Qingda liu Libo Li xun Wang Jinghong Li Department of Chemistry Center for BioAnalytical ChemistryKey Laboratory of Bioorganic Phosphorus Chemistry&Chemical BiologyTsinghua UniversityBeijing 100084China School of Chemistry and Chemical Engineering Guangdong Prov Key Lab Green Chem Prod TechnolSouth China University of TechnologyGuangzhou 510640China New Cornerstone Science Laboratory Shenzhen 518054China Beijing Institute of Life Science and Technology Beijing 102206China Center for BioAnalytical Chemistry Hefei National Laboratory of Physical Science at MicroscaleUniversity of Science and Technology of ChinaHefei 230026China

It is important and challenging to analyze nanocluster structure with atomic precision.Herein,α-hemolysin nanopore was used to identify nanoclusters at the single molecule level by providing two-dimensional(2D)dwell time–current blockage spectra and translocation event frequency which sensitively depended on their structures.Nanoclusters such as Anderson,Keggin,Dawson,and a few lacunary Dawson polyoxometalates with very similar structures,even with only a two-atom difference,could be discriminated.This nanopore device could simultaneously measure multiple nanoclusters in a mixture qualitatively and quantitatively.Furthermore,molecular dynamics(MD)simulations provided microscopic understandings of the nanocluster translocation dynamics and yielded 2D dwell time–current blockage spectra in close agreement with experiments.The nanopore platform provides a novel powerful tool for nanocluster characterization.

关键词： nanopore single-molecule nanocluster polyoxometalates real-time detection

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Neuroprotective effects of acteoside in a glaucoma mouse model by targeting Serta domain-containing protein 4

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 625-637页

作者： Hui-Jie Hao Ya-Hong Li Bo Yu xun liu Yan Zhang Xiao-Li Xing Tianjin Key Laboratory of Retinal Functions and Diseases Tianjin Branch of National Clinical Research Center for Ocular DiseaseEye Institute and School of OptometryTianjin Medical University Eye HospitalTianjin 300384China

AIM:To explore the therapeutic effect and main molecular mechanisms of acteoside in a glaucoma model in DBA/2J mice.METHODS:Proteomics was used to compare the differentially expressed proteins of C57 and DBA/2J mice.After acteoside administration in DBA/2J mice,anterior segment observation,intraocular pressure(IOP)monitoring,electrophysiology examination,and hematoxylin and eosin staining were used to analyze any potential effects.Immunohistochemistry(IHC)assays were used to verify the proteomics results.Furthermore,retinal ganglion cell 5(RGC5)cell proliferation was assessed with cell counting kit-8(CCK-8)assays.Serta domain-containing protein 4(Sertad4)mRNA and protein expression levels were measured by qRT-PCR and Western blot analysis,respectively.RESULTS:Proteomics analysis suggested that Sertad4 was the most significantly differentially expressed protein.Compared with the saline group,the acteoside treatment group showed decreased IOP,improved N1-P1 wave amplitudes,thicker retina,and larger numbers of cells in the ganglion cell layer(GCL).The IHC results showed that Sertad4 expression levels in DBA/2J mice treated with acteoside were significantly lower than in the saline group.Acteoside treatment could improve RGC5 cell survival and reduce the Sertad4 mRNA and protein expression levels after glutamate injury.CONCLUSION:Sertad4 is differentially expressed in DBA/2J mice.Acteoside can protect RGCs from damage,possibly through the downregulation of Sertad4,and has a potential use in glaucoma treatment.

关键词： glaucoma acteoside Serta domaincontaining protein 4 proteomics mice

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