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Innovative construction of macroporous–mesoporous structured spherical alumina and its hydrothermal stability

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Particuology 2024年第7期90卷 429-435页

作者： Yufan mo Chunli li Huiyu li Wei Han He Wen Yinghong Han Chunxia Che Yongjun Feng State Key Laboratory of Chemical Resource Engineering Beijing Engineering Center for Hierarchical CatalystsCollege of ChemistryBeijing University of Chemical TechnologyBeijing100029China Lanzhou Petrochemical Research Center Petrochemical Research InstitutePetroChinaLanzhou730060China

The pore structure of spherical alumina supports is closely related to the dispersion of catalytically active components and the diffusion of *** excellent pore structure under strict reaction conditions is of utmost *** this work,sphericalγ-Al_(2)O_(3)support with a bimodal pore structure,composed of macropores and mesopores,was successfully synthesized using dodecane as the pore-forming agent through the oil–ammonia column-shaping *** morphology and internal pore structure of the alumina were found to be influenced by the amount of surfactant added and ultrasound treatment ***,when concentration of surfactant was 4‰and ultrasound voltage of 20 V was applied,the resultingγ-Al_(2)O_(3)-4‰-20 displayed a highly concentrated distribution of macropores with an average pore size of 100 nm,resulting in an impressive porosity of 69.21%.In contrast,the untreated sample ofγ-Al_(2)O_(3)-0-0 only exhibited a mesoporous distribution with a porosity of 54.03%.moreover,after being subjected to a hydrothermal treatment in a high temperature(600°C)and high humidity(water vapor)environment for 120 h,theγ-Al_(2)O_(3)-4‰-20 sample maintained a high BET specific surface area of 170.9 m^(2)g^(−1)and mercury intrusion porosimetry specific surface area of 263.3 m^(2)g^(−1).

关键词： Spherical alumina supports Pore-forming agent Oil-ammonia column shaping method Hydrothermal treatment Hydrothermal stability

Effects of weaning on intestinal longitudinal muscle-myenteric plexus function in piglets

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Science China(life Sciences) 2024年第2期67卷 379-390页

作者： Jing li Fenfen liu Kaibin mo Hengjia Ni Yulong Yin Key Laboratory of Agro-Ecological Processes in Subtropical Region Hunan Provincial Key Laboratory of Animal Nutritional Physiology and Metabolic ProcessHunan Research Center of Livestock and Poultry SciencesSouth Central Experimental Station of Animal Nutrition and Feed Science in the Ministry of AgricultureInstitute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125China University of Chinese Academy of Sciences Beijing 100008China Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation College of Veterinary MedicineSouth China Agricultural UniversityGuangzhou 510642China

Weaning piglets usually suffer from severe diarrhea(commonly known as postweaning diarrhea,PWD)along with intestinal motility *** peristalsis is mainly regulated by the longitudinal muscle-myenteric plexus(LM-MP).To understand the relationship between intestinal LM-MP function and the development of PWD,we compared the intestinal electrical activity,and the transcriptional profile of the LM-MP between 21-day-old piglets(just weaned,n=7)and 24-day-old piglets(suffered the most severe weaning stress,n=7).The results showed that 24-day-old piglets exhibited different degrees of diarrhea.A significant increase in the slow-wave frequency in the ileum and colon was observed in 24-day-old piglets,while c-kit expression in the intestinal LM-MPs was significantly decreased,indicating that PWD caused by elevated slow-wave frequency may be associated with loss of *** real-time quantitative PCR(RT-q PCR)and enzyme-linked immunosorbent assay(EliSA)showed that intestinal LM-MPs in 24-day-old piglets may undergo inflammation and oxidative *** increases in 8-hydroxy-2′-deoxyguanosine and decreases in thioredoxin suggest that weaning may lead to DNA damage in the LM-MP of 24-day-old *** addition,activating transcription factor 3 was significantly upregulated,indicating nerve damage in the LM-MP of 24-day-old *** transcriptomic results showed that most of the differentially expressed genes in the ileal LM-MP after weaning were downregulated and closely related to the cell cycle *** RT-q PCR analysis showed that the relative expression of p21 was upregulated,while the expression of cyclin A2,cyclin B1,and proliferating cell nuclear antigen was downregulated in the ileal and colonic LM-MP of 24-day-old piglets,suggesting that weaning may inhibit cell proliferation and cause G1/S cell cycle arrest in ileal and colonic *** conclusion,weaning may lead to cell cycle arrest by causing DNA damage in the LM-MP,impairing i

关键词： weaning piglets diarrhea longitudinal muscle-myenteric plexus

Transplantation of fibrin-thrombin encapsulated human induced neural stem cells promotes functional recovery of spinal cord injury rats through modulation of the microenvironment

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Neural Regeneration Research 2024年第2期19卷 440-446页

作者： Sumei liu Baoguo liu Qian li Tianqi Zheng Bochao liu mo li Zhiguo Chen Cell Therapy Center Beijing Institute of GeriatricsXuanwu HospitalCapital Medical UniversityNational Clinical Research Center for Geriatric Diseasesand Key Laboratory of Neurodegenerative DiseasesMinistry of EducationBeijingChina Center of Neural Injury and Repair Beijing Institute for Brain DisordersBeijingChina Center of Parkinson’s Disease Beijing Institute for Brain DisordersBeijingChina

Recent studies have mostly focused on engraftment of cells at the lesioned spinal cord,with the expectation that differentiated neurons facilitate *** a few studies have attempted to use transplanted cells and/or biomaterials as major modulators of the spinal cord injury ***,we aimed to investigate the role of microenvironment modulation by cell graft on functional recovery after spinal cord *** neural stem cells reprogrammed from human peripheral blood mononuclear cells,and/or thrombin plus fibrinogen,were transplanted into the lesion site of an immunosuppressed rat spinal cord injury ***,Beattie and Bresnahan score,electrophysiological function,and immunofluorescence/histological analyses showed that transplantation facilitates motor and electrophysiological function,reduces lesion volume,and promotes axonal neurofilament expression at the lesion *** of the graft and niche components revealed that although the graft only survived for a relatively short period(up to 15 days),it still had a crucial impact on the ***,induced neural stem cells and human fibrin reduced the number of infiltrated immune cells,biased microglia towards a regenerative M2 phenotype,and changed the cytokine expression profile at the lesion ***-induced changes of the microenvironment during the acute and subacute stages might have disrupted the inflammatory cascade chain reactions,which may have exerted a long-term impact on the functional recovery of spinal cord injury rats.

关键词： biomaterial fibrinogen functional recovery induced neural stem cell transplantation microenvironment microglia spinal cord injury thrombin

Thirty-eight spider species (Arachnida: Araneae) from China, Indonesia, Japan and Vietnam

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Zoological Systematics 2024年第1期49卷 4-98页

作者： Yejie lin Shuqiang li Haolin mo Xihao Wang Institute of Zoology Chinese Academy of SciencesBeijing 100101China Key Laboratory of Wildlife Evolution and Conservation in mountain Ecosystem of Guangxi Nanning Normal UniversityNanning 530001China Jinan licheng No.2 High School Jinan 250109China

Four new genera in three spider families are reported, namely Langlibaitiao lin &li, gen. nov., of Dictynidae O. Pickard-Cambridge, 1871, with Lathys inaffecta li, 2017(♂♀,China: Guangxi) as the type species;Huoyanluo lin & li, gen. nov., of Macrobunidae Petrunkevitch, 1928, with Huoyanluo ruanxiaoqi lin & li, sp. nov.(♂, China: Yunnan) as the type species and Gushangzao lin & li, gen. nov. and Gyro lin & li, gen. nov., of Theridiidae Sundevall, 1833, with Gushangzao shiqian lin & li, sp. nov.(♂♀, China: Xizang) and Gyro zeppeli lin & li, sp. nov.(♀, China: Yunnan) as the type species, respectively. Further 31 new species in 19 spider families are reported, including Agelenidae C.L. Koch, 1837:Troglocoelotes doul lin & li, sp. nov.(♀, China: Guangxi) and T. ruanxiaowu lin & li, ***.(♀, China: Guangxi);Dictynidae: Langlibaitiao zhangshun lin & li, sp. nov.(♂, China:Hainan);Hahniidae Bertkau, 1878: Hahnia zhuyifani lin & li, sp. nov.(♀, China: Yunnan);liocranidae Simon, 1897: Platnick xintongi lin & li, sp. nov.(♂♀, China: Xizang);Macrobunidae: Funny yanqing lin & li, sp. nov.(♂♀, China: Xizang) and Huoyanluo zhangzezhongi lin & li, sp. nov.(♂, China: Yunnan);Mysmenidae Petrunkevitch, 1928:Phricotelus yangxiong lin & li, sp. nov.(♂♀, China: Chongqing);Nemesiidae Simon, 1889:Raveniola shixiu lin, Wang & li, sp. nov.(♀, China: Guangxi) and R. xiezhen lin, Wang & li,sp. nov.(♂♀, China: Yunnan);Nesticidae Simon,1894: Speleoticus sicet lin & li, sp. nov.(♂♀,China: Sichuan);Ochyroceratidae Fage, 1912: Speocera yiduoi lin & li, sp. nov.(♂, China:Guangdong);Oecobiidae Blackwall, 1862: Uroctea chenyui lin & li, sp. nov.(♂♀, China:Guangxi);Oonopidae Simon, 1890: Orchestina xiebao lin & li, sp. nov.(♀, China:Chongqing);Philodromidae Thorell, 1869: Apollophanes lujiani lin & li, sp. nov.(♂♀, China:Guangxi) and Psellonus dawanqu lin & li, sp. nov.(♂♀, China: Guangdong);Salticidae Blackwall, 1841: Coccorchestes spark lin & li, sp. nov.(♂♀, Indonesia, West Papua),Onomastus zhuwu

关键词： Diagnosis new combination new genus new species Asia.

Metastability of π-π stacking between the closed-shell ions of like charges

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Chinese Journal of Structural Chemistry 2024年第5期43卷 22-29页

作者： Jiayao li Xinru Peng Shiwei Yin changwei Wang Yirong mo Key Laboratory for Macromolecular Science of Shaanxi Province School of Chemistry&Chemical EngineeringShaanxi Normal UniversityXi'an710119China Department of Nanoscience Joint School of Nanoscience&NanoengineeringUniversity of North Carolina at GreensboroGreensboroNC 27401USA

Planar cations or anions can form stacks in crystals or solutions,where the surrounding or environment plays a decisive role as demonstrated in previous ***,it remains unclear whether these counterintuitive interactions possess any inherent stability or are thoroughly repulsive if the constraint of environment is *** this work,we explored the inherent stability ofπ-πstacking between closed-shell ions of like charges with prototypes derived from experimental *** inherent metastability was identified by the characteristic local minima and the transition states preventing their dissociation and verified by ab initio molecular dynamics(AIMD)*** nature of involved interactions was deciphered with the energy decomposition approach based on the block-localized wavefunction method(BLW-ED).like the conventional neutralπ-πstacking interactions,electron correlation is the most attractive energy *** it is overturned by the Coulombic repulsion between net charges for all modes of dimerization,resulting in the overall repulsive inter-cation or anion *** from van der Waals interactions were also observed in the reduced density gradient *** origin of the metastability was elucidated by examining the contributions of individual physical factors to the *** inherent metastability originates from the electron correlation,which dramatically increases due to the enhanced overlap between ions from a transition state to its corresponding minimum.

关键词： π-πstacking interactions Metastability Valence bond theory Energy decomposition analysis Electron correlation

Prox1 Suppresses Proliferation and Drug Resistance of Retinoblastoma Cells via Targeting Notch1

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Current Medical Science 2024年第1期44卷 223-231页

作者： Hong-li ZHANG Na li lin DONG Hong-xia MA mo-chi YANG Department of Ophthalmology General Hospital of Ningxia Medical UniversityYinchuan 750004China

Objective Retinoblastoma(RB)is a prevalent type of eye cancer in *** homeobox 1(Prox1)is a homeobox transcriptional repressor and downstream target of the proneural gene that is relevant in lymphatic,hepatocyte,pancreatic,heart,lens,retinal,and cancer *** goal of this study was to investigate the role of Prox1 in RB cell proliferation and drug resistance,as well as to explore the underlying Notch1 *** Human RB cell lines(SO-RB50 and Y79)and a primary human retinal microvascular endothelial cell line(ACBRI-181)were used in this *** expression of Prox1 and Notch1 mRNA and protein in RB cells was detected using quantitative real time-polymerase chain reaction(RT-qPCR)and Western *** proliferation was assessed after Prox1 overexpression using the Cell Counting Kit-8 and the MTS ***-resistant cell lines(SO-RB50/vincristine)were generated and treated with Prox1 to investigate the role of Prox1 in drug *** employed pcDNA-Notch1 to overexpress Notch1 to confirm the role of Notch1 in the protective function of ***,a xenograft model was constructed to assess the effect of Prox1 on RB in *** Prox1 was significantly downregulated in RB *** of Prox1 effectively decreased RB cell growth while increasing the sensitivity of drug-resistant cells to ***1 was involved in Prox1’s regulatory ***1 was identified as a target gene of Prox1,which was found to be upregulated in RB cells and repressed by increased Prox1 *** pcDNA-Notch1 was transfected,the effect of Prox1 overexpression on RB was ***,by downregulating Notch1,Prox1 overexpression slowed tumor development and increased vincristine sensitivity in *** These data show that Prox1 decreased RB cell proliferation and drug resistance by targeting Notch1,implying that Prox1 could be a potential therapeutic target for RB.

关键词： Proxl Notch1 retinoblastoma cells proliferation drug resistance

Unknown system dynamics estimator-based impedance control for lower limb exoskeleton with enhanced performance

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Control Theory and Technology 2024年第1期22卷 56-68页

作者： Wenhao Zhang Peng Song Mingying Wu Qiang li Xinmin mo Pingxin Ji Northwest Institute of Mechanical and Electrical Engineering Xianyang712099ShaanxiChina Xi’an Exo-Smart Dynamics Technology Ltd. Xi’an712046ShaanxiChina Department of Mechanical and Engineering Beijing Institute of TechnologyBeijing100081China

In this article, an unknown system dynamics estimator-based impedance control method is proposed for the lower limb exoskeleton to stimulate the tracking flexibility with the terminal target position when suffering parametric inaccuracies and unexpected disturbances. To reinforce the robust performance, via constructing the filtering operation-based dynamic relation, i.e., invariant manifold, the unknown system dynamics estimators are employed to maintain the accurate perturbation identification in both the hip and knee subsystem. Besides, a funnel control technique is designed to govern the convergence process within a minor overshoot and a higher steady-state precision. Meanwhile, an interactive complaint result can be obtained with the aid of the impedance control, where the prescribed terminal trajectory can be adjusted into the interaction variable-based target position by the force–position mapping, revealing the dynamic influence between the impedance coefficient (stiffness and damping) and the adjusted position magnitude. A sufficient stability analysis verifies the ultimately uniformly bounded results of all the error signals, and even the angle errors can be regulated within the predefined funnel boundary in the whole convergence. Finally, some simulations are provided to demonstrate the validity and superiority including the enhanced interaction flexibility and robustness.

关键词： Trajectory tracking Invariant manifold Funnel control Impedance control Lower limb exoskeleton

Refined acoustic holography via nonlocal metasurfaces

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 113-123页

作者： Shuhuan Xie Hongyu Ma Junmei Cao Fangshuo mo Qian Cheng Yong li Tong Hao Institute of Acoustics School of Physics Science and EngineeringTongji UniversityShanghai 200092China Center for Spatial Information Science and Sustainable Development Applications Tongji UniversityShanghai 200092China College of Surveying and Geo-Informatics Tongji UniversityShanghai 200092China

Holography can provide the desired wavefront phase and/or amplitude for imaging,particle manipulation,bacteria trapping,and cell patterning in optics and ***,previous work on acoustic holography is mostly based on local design optimization,either using active control of the sound source or relying on the structural design to provide the desired *** precise control over the acoustic field remains a significant ***,we realize refined single-plane symmetric binary amplitude,asymmetric intensity gradient amplitude,and bi-objective hologram through the non-local holographic imaging theory that considers the acoustic coupling of structural units in *** taking into account the self-radiation and mutual radiation between many small units on a plate of well-designed thickness,as well as the transmission through the plate's apertures,we can effectively regulate the sound field behind the *** demonstrate the effectiveness of our approach through numerical simulations and experiments,showcasing a circle,a black hole,and a bi-objective with a circle and a square ***,the acoustic black hole hologram precisely reconstructs the intensity gradient distribution at two bright *** non-local holographic imaging theory is valuable for the fine-intensity regulation of the sound field and is expected to be applied in ultrasound diagnosis and treatment,medical imaging,and other fields.

关键词： acoustic holograms non-local interactions fine intensity modulation acoustic metasurfaces

An efficient labeled memory system for learned indexes

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Fundamental Research 2024年第3期4卷 651-659页

作者： Yuxuan mo Jingnan Jia Pengfei li Yu Hua Huazhong University of Science and Technology Wuhan 430074China

The appearance and wide use of memory hardware bring significant changes to the conventional vertical memory hierarchy that fails to handle contentions for shared hardware resources and expensive data *** deal with these problems,existing schemes have to rely on inefficient scheduling strategies that also cause extra temporal,spatial and bandwidth *** on the insights that the shared hardware resources trend to be uniformly and hierarchically offered to the requests for co-located applications in memory systems,we present an efficient abstraction of memory hierarchies,called Label,which is used to establish the connection between the application layer and underlying hardware *** on labels,our paper proposes LaMem,a labeled,resource-isolated and cross-tiered memory system by leveraging the way-based partitioning technique for shared resources to guarantee QoS demands of applications,while supporting fast and low-overhead cache repartitioning ***,we customize LaMem for the learned index that fundamentally replaces storage structures with computation models as a case study to verify the applicability of *** results demonstrate the efficiency and efficacy of LaMem.

关键词： Heterogeneous memory system Cache hierarchy Data movement Resource contention Learned index