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"Light-on"Colorimetric Assay for Ascorbic Acid Detection via boosting the Peroxidase-like Activity of Fe-MIL-88

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Journal of Analysis and Testing 2022年第1期6卷 67-75页

作者： Chuan-xia chen cheng-hui Zhang peng-juan Ni yuan-yuan Jiang bo Wang Yi-zhong Lu School of Materials Science and Engineering University of JinanJinan 250022China

A label-free"light-on"colorimetric assay for ascorbic acid(AA)determination is unprecedentedly devised by regulating the intrinsic peroxidase-mimetic activity of the Fe-MIL-88.AA can reduce Fe(Ⅲ)presented in Fe-MIL-88 to Fe(Ⅱ),which will dramatically promote the hydroxyl radicals(·OH)conversion efficiency of H_(2)O_(2)through a Fenton reaction,and effectually accelerate the Fe-MIL-88 catalyzed chromogenic reaction of 3,3′,5,5′-tetramethylbenzidine(TMB)-H_(2)O_(2).Redox reaction between AA and H_(2)O_(2)also can produce·OH and promote this chromogenic reaction.Thus,quantification of AA is real-ized via determining the enhanced colorimetric signals.The linear range is 0.5−40μM with a detection limit of 0.12μM.Furthermore,the straightforward yet effective colorimetric strategy with the merits of simplicity,cost-effectiveness,high accuracy,specificity,and sensitivity is widely utilized to determine the concentrations of AA in serological tests.

关键词： Ascorbic acid Colorimetric Fe-MIL-88 Hydroxyl radicals Fenton reaction

Insights into carbon-based materials for catalytic dehydrogenation of low-carbon alkanes and ethylbenzene

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Frontiers of Chemical Science and Engineering 2023年第11期17卷 1623-1648页

作者： Sijia Xing Sixiang Zhai lei chen Huabin Yang zhong-Yong yuan School of Materials Science and Engineering Smart Sensing Interdisciplinary Science CenterNankai UniversityTianjin 300350China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

Direct dehydrogenation with high selectivity and oxidative dehydrogenation with low thermal limit has been regarded as promising methods to solve the increasing demands of light olefins and styrene.Metalbased catalysts have shown remarkable performance for these reactions,such as Pt,CrOx,Co,ZrOx,Zn and V.Compared with metal-based catalysts,carbon materials with stable structure,rich pore texture and large surface area,are ideal platforms as the catalysts and the supports for dehydrogenation reactions.In this review,carbon materials applied in direct dehydrogenation and oxidative dehydrogenation reactions including ordered mesoporous carbon,carbon nanodiamond,carbon nanotubes,graphene and activated carbon,are summarized.A general introduction to the dehydrogenation mechanism and active sites of carbon catalysts is briefly presented to provide a deep understanding of the carbon-based materials used in dehydrogenation reactions.The unique structure of each carbon material is presented,and the diversified synthesis methods of carbon catalysts are clarified.The approaches for promoting the catalytic activity of carbon catalysts are elaborated with respect to preparation method optimization,suitable structure design and heteroatom doping.The regeneration mechanism of carbon-based catalysts is discussed for providing guidance on catalytic performance enhancement.In addition,carbon materials as the support of metal-based catalysts contribute to exploiting the excellent catalytic performance of catalysts due to superior structural characteristics.In the end,the challenges in current research and strategies for future improvements are proposed.

关键词： carbon materials dehydrogenation active sites mechanism catalytic performance support

Loss of LBP triggers lipid metabolic disorder through H3K27 acetylation-mediated C/EBPβ-SCD activation in non-alcoholic fatty liver disease

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Zoological Research 2024年第1期45卷 79-94页

作者： Ya-Ling Zhu lei-lei Meng Jin-Hu Ma Xin yuan Shu-Wen chen Xin-Rui Yi Xin-Yu Li Yi Wang yun-Shu Tang Min Xue Mei-Zi Zhu Jin peng Xue-Jin Lu Jian-Zhen Huang Zi-chen Song Chong Wu Ke-zhong Zheng Qing-Qing Dai Fan Huang Hao-Shu Fang Department of Pathophysiology Anhui Medical UniversityHefeiAnhui 230032China Laboratory Animal Research Center School of Basic Medical SciencesAnhui Medical UniversityHefeiAnhui 230032China Department of Hepatobiliary Surgery First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui 230022China College of Animal Science and Technology Jiangxi Agricultural UniversityNanchangJiangxi 330045China

Non-alcoholic fatty liver disease(NAFLD)is associated with mutations in lipopolysaccharide-binding protein(LBP),but the underlying epigenetic mechanisms remain understudied.Herein,LBP^(-/-)rats with NAFLD were established and used to conduct integrative targetingactive enhancer histone H3 lysine 27 acetylation(H3K27ac)chromatin immunoprecipitation coupled with high-throughput and transcriptomic sequencing analysis to explore the potential epigenetic pathomechanisms of active enhancers of NAFLD exacerbation upon LBP deficiency.Notably,LBP^(-/-)reduced the inflammatory response but markedly aggravated high-fat diet(HFD)-induced NAFLD in rats,with pronounced alterations in the histone acetylome and regulatory transcriptome.In total,1128 differential enhancer-target genes significantly enriched in cholesterol and fatty acid metabolism were identified between wild-type(WT)and LBP^(-/-)NAFLD rats.Based on integrative analysis,CCAAT/enhancer-binding proteinβ(C/EBPβ)was identified as a pivotal transcription factor(TF)and contributor to dysregulated histone acetylome H3K27ac,and the lipid metabolism gene SCD was identified as a downstream effector exacerbating NAFLD.This study not only broadens our understanding of the essential role of LBP in the pathogenesis of NAFLD from an epigenetics perspective but also identifies key TF C/EBPβand functional gene SCD as potential regulators and therapeutic targets.

关键词： Non-alcoholic fatty liver disease C/EBPβ Lipopolysaccharide-binding protein H3K27ac Integrative analysis Enhancer

Low-Frequency Magnetic Stimulation of Shenmen Acupoint Reduces Blood Oxygen Levels in the Prefrontal Cortex of Healthy Subjects:A Near-Infrared Brain Functional Imaging Study

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Chinese Journal of Integrative Medicine 2021年第8期27卷 585-588页

作者： yuan Jie ZHENG zhong CAO Yue chen Jie LI yuan-yuan lei Ya-ling School of Basic Medical Sciences Chengdu University of Traditional Chinese MedicineChengdu611130China Department of Encephalopathy Shaanxi Provincial Hospital of Traditional Chinese MedicineXi’an710003China Neurobiologic Testing Center Sichuan University West China HospitalChengdu610044China College of Acupuncture and Massage Chengdu University of Traditional Chinese MedicineChengdu611130China Department of Ophthalmology Xi’an Hospital of Traditional Chinese MedicineXi’an710003China

Objective To explore the effect of low-frequency magnetic stimulation at Shenmen(HT 7)acupoint on blood oxygen levels in the prefrontal cortex of healthy subjects.Methods Functional near-infrared spectroscopy(fNIRS)technology was used to collect real-time data of oxygenated hemoglobin(oxy-Hb)in the prefrontal cortex of 16 healthy subjects at resting state and low-frequency magnetic stimulation of Shenmen.The mean and integral values of blood oxygen concentration were analyzed.Results Compared with the resting state,the mean and integral values of blood oxygen concentration were decreased during the task period,recovery period,and the whole process in the magnetic stimulation of Shenmen acupoint(P<0.05).In particular,the difference was statistically significant in the recovery period(P<0.01).Conclusions The prefrontal cortex was widely activated and produced an immediate effect by reducing the local blood oxygen concentration at low-frequency magnetic stimulation of Shenmen acupoint,which verifies the sedative effect of Shenmen acupoint.

关键词： Shenmen acupoint transcranial magnetic stimulation functional near-infrared spectroscopy prefrontal lobe healthy subjects

Implications on the origin of cosmic rays in light of 10 TV spectral softenings

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Frontiers of physics 2020年第2期15卷 101-109,F0004页

作者： Cliuan Yue peng-Xiong Ma Qiang yuan Yi-zhong Fan Zhan-Fang chen Ming-Yang Cui Hao-Ting Dai Tie-Kuang Dong Xiaoyuan Huang Wei Jiang Shi-Jun lei Xiang Li cheng-Ming Liu Hao Liu Yang Liu Chuan-Ning Luo Xu Pan Wen-Xi peng Rui Qiao Yi-Feng Wei Li-bo Wu Zhi-Hui Xu Zun-lei Xu Guan-Wen yuan Jing-Jing Zang Ya-peng Zhang Yong-Jie Zhang yun-Long Zhang Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210033China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Center for High Energy Physics Peking UniversityBeijing 100871China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Institute of Modem Physics Chinese Academy of SciencesLanzhou 730000China

Precise measurements of the energy spectra of cosmic rays(CRs)show various kinds of features deviating from single power-laws,which give very interesting and important implications on their origin and propagation.Previous measurements from a few balloon and space experiments indicate the existence of spectral softenings around 10 TV for protons(and probably also for Helium nuclei).Very recently,the DArk Matter Particle Explorer(DAMPE)measurement about the proton spectrum clearly reveals such a softening with a high significance.Here we study the implications of these new measurements,as well as the groundbased indirect measurements,on the origin of CRs.We find that a single component of CRs fails to fit the spectral softening and the air shower experiment data simultaneously.In the framework of multiple components,we discuss two possible scenarios,the multiple source population scenario and the background plus nearby source scenario.both scenarios give reasonable fits to the wide-band data from TeV to 100 PeV energies.Considering the anisotropy observations,the nearby source model is favored.

关键词： cosmic rays

Study on the preservation effects of the amputated forelimb by machine perfusion at physiological temperature

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Chinese Journal of Traumatology 2024年第2期27卷 114-120页

作者： Sheng-Feng chen bo-Yao Yang Tie-yuan Zhang Xiang-Yu Song Zhi-bo Jia lei-Jia chen Meng-Yi Cui Wen-Jing Xu Jiang peng Guizhou Medical University Guiyang550025China Medical School of PLA Beijing100048 China Beijing Key Lab of Regenerative Medicine in Orthopedics Key Laboratory of Musculoskeletal Trauma and War Injuries PLADepartment of OrthopedicsThe Fourth Medical CenterChinese PLA General HospitalBeijing100048China Hebei North Universiy Zhangjiakou075000Hebei ProvinceChina

Purpose:Ischemia and hypoxia are the main factors limiting limb replantation and transplantation.Static cold storage(SCS),a common preservation method for tissues and organs,can only prolong limb ischemia time to 4-6 h.The normothermic machine perfusion(NMP)is a promising method for the preservation of tissues and organs,which can extend the preservation time in vitro by providing continuous oxygen and nutrients.This study aimed to evaluate the difference in the efficacy of the 2 limb preservation methods.Methods:The 6 forelimbs from beagle dogs were divided into 2 groups.In the SCS group(n=3),the limbs were preserved in a sterile refrigerator at 4°C for 24 h,and in the NMP group(n=3),the perfusate prepared with autologous blood was used for the oxygenated machine perfusion at physiological temperature for 24 h,and the solution was changed every 6 h.The effects of limb storage were evaluated by weight gain,perfusate biochemical analysis,enzyme-linked immunosorbent assay,and histological analysis.All statistical analyses and graphs were performed using GraphPad Prism 9.0 one-way or two-way analysis of variance.The p value of less than 0.05 was considered to indicate statistical significance.Results:In the NMP group,the weight gained percentage was 11.72%±4.06%;the hypoxia-inducible factor-1αcontents showed no significant changes;the shape of muscle fibers was normal;the gap between muscle fibers slightly increased,showing the intercellular distance of(30.19±2.83)μm;and the vascularα-smooth muscle actin(α-SMA)contents were lower than those in the normal blood vessels.The creatine kinase level in the perfusate of the NMP group increased from the beginning of perfusion,decreased after each perfusate change,and remained stable at the end of perfusion showing a peak level of 4097.6 U/L.The lactate dehydrogenase level of the NMP group increased near the end of perfusion and reached the peak level of 374.4 U/L.In the SCS group,the percentage of weight gain was 0.18%±0.10%,and the contents of hypoxia-inducible factor-1αin

关键词： Traumatic amputation Machine perfusion Static cold storage Limb replantation

Feature-Grounded Single-Stage Text-to-Image Generation

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Tsinghua Science and Technology 2024年第2期29卷 469-480页

作者： yuan Zhou peng Wang lei Xiang Haofeng Zhang School of Artificial Intelligence Nanjing University of Information Science and TechnologyNanjing 210044China School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China

Recently,Generative Adversarial Networks(GANs)have become the mainstream text-to-image(T2I)framework.However,a standard normal distribution noise of inputs cannot provide sufficient information to synthesize an image that approaches the ground-truth image distribution.Moreover,the multistage generation strategy results in complex T2I applications.Therefore,this study proposes a novel feature-grounded single-stage T2I model,which considers the“real”distribution learned from training images as one input and introduces a worst-case-optimized similarity measure into the loss function to enhance the model's generation capacity.Experimental results on two benchmark datasets demonstrate the competitive performance of the proposed model in terms of the Frechet inception distance and inception score compared to those of some classical and state-of-the-art models,showing the improved similarities among the generated image,text,and ground truth.

关键词： text-to-image(T2I) feature-grounded single-stage generation Generative Adversarial Network(GAN)

Metarelation2vec:A Metapath-Free Scalable Representation Learning Model for Heterogeneous Networks

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Tsinghua Science and Technology 2024年第2期29卷 553-575页

作者： lei chen yuan Li Yong lei Xingye Deng School of Information and Electrical Engineering Hunan University of Science and TechnologyXiangtan 411201China School of Computer Science and Engineering Hunan University of Science and TechnologyXiangtan 411201China

Metapaths with specific complex semantics are critical to learning diverse semantic and structural information of heterogeneous networks(HNs)for most of the existing representation learning models.However,any metapaths consisting of multiple,simple metarelations must be driven by domain experts.These sensitive,expensive,and limited metapaths severely reduce the flexibility and scalability of the existing models.A metapath-free,scalable representation learning model,called Metarelation2vec,is proposed for HNs with biased joint learning of all metarelations in a bid to address this problem.Specifically,a metarelation-aware,biased walk strategy is first designed to obtain better training samples by using autogenerating cooperation probabilities for all metarelations rather than using expert-given metapaths.Thereafter,grouped nodes by the type,a common and shallow skip-gram model is used to separately learn structural proximity for each node type.Next,grouped links by the type,a novel and shallow model is used to separately learn the semantic proximity for each link type.Finally,supervised by the cooperation probabilities of all meta-words,the biased training samples are thrown into the shallow models to jointly learn the structural and semantic information in the HNs,ensuring the accuracy and scalability of the models.Extensive experimental results on three tasks and four open datasets demonstrate the advantages of our proposed model.

关键词： metarelation random walk heterogeneous network metapath representation learning

Single Peak Solutions for a Schr?dinger Equation with Variable Exponent

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Acta Mathematica Sinica,English Series 2023年第11期39卷 2207-2218页

作者： zhong yuan LIU peng LUO Hua Fei XIE School of Mathematics and Statistics He’nan UniversityKaifeng 475004P.R.China School of Mathematics and Statistics&Hubei Key Laboratory of Mathematical Sciences Central China Normal UniversityWuhan 430079P.R.China School of Mathematics and Statistics Nanyang Normal UniversityNanyang 473061P.R.China

We study the following Schr?dinger equation with variable exponent−Δu+u=u^(p+∈a)(x),u>0 in R^(N),where∈>0,1 详细信息

We study the following Schr?dinger equation with variable exponent−Δu+u=u^(p+∈a)(x),u>0 in R^(N),where∈>0,1bove problem.We also obtain local uniqueness and exact multiplicity results for this problem by the Pohozaev type identity.

关键词： Single peak solutions Schr?dinger equation variable exponent