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The dawn−dusk asymmetry in mesosphere and lower thermosphere temperature disturbances during geomagnetic storms at high latitude

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Earth and Planetary Physics 2024年第2期8卷 356-367页

作者： GuanChun Wei JianYong Lu Fen Tang jingyuan li Meng Sun Institute of Space Weather School of Atmospheric PhysicsNanjing University of Information Science&TechnologyNanjing 210044China College of Information and Communication National University of Defense TechnologyWuhan 430019China

Utilizing observations by the Sounding of the Atmosphere using Broadband Emission Radiometry(SABER)instrument,we quantitatively assessed the dawn-dusk asymmetry in temperature disturbances within the high-latitude mesosphere and lower thermosphere(MLT)during the main phase of geomagnetic storms in this study.An analysis of five geomagnetic superstorm events indicated that during the main phase,negative temperature disturbances were more prevalent on the dawn side than on the dusk side in the high-latitude MLT region.Results of a statistical analysis of 54 geomagnetic storm events also revealed a notable disparity in temperature disturbances between the dawn and dusk sides.At high latitudes,38.2%of the observational points on the dawn side exhibited negative temperature disturbances(less than−5 K),whereas on the dusk side,this percentage was only 29.5%.In contrast,at mid-latitudes,these proportions were 34.1%and 36.5%,respectively,showing no significant difference.We also conducted a statistical analysis of temperature disturbances at different altitudes,which revealed an increase in the proportion of warming disturbances with altitude.Conversely,the proportion of cooling disturbances initially rose with altitude,reaching a peak around 105 km,and subsequently decreased.These temperature disturbance differences could be explained by the day-night asymmetry in vertical wind disturbances during storm conditions.

关键词： dawn dusk asymmetry SABER(Sounding of the Atmosphere using Broadband Emission Radiometry) geomagnetic storms mesosphere and lower thermosphere

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Enhanced extracellular production of alpha-lactalbumin from Bacillus subtilis through signal peptide and promoter screening

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Food Science and Human Wellness 2024年第4期13卷 2310-2316页

作者： Yuqi Zhu Pengdong Sun Chunjian li Yu Zhang Yu Wang jingyuan li Yanfeng liu Jian Chen Yang Deng College of Food Science and Engineering Qingdao Agricultural UniversityQingdao 266109China Key Laboratory of Special Food Processing(Co-construction by Ministry and Province) Ministry of Agriculture Rural AffairsQingdao Agricultural UniversityQingdao 266109China Qingdao Special Food Research Institute Qingdao 266109China Science Center for Future Foods Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan UniversityWuxi 214122China Key Laboratory of Carbohydrate Chemistry and Biotechnology Ministry of EducationSchool of BiotechnologyJiangnan UniversityWuxi 214122China

Alpha-lactalbumin(α-LA)is a major whey protein found in breast milk and plays a crucial role in the growth and development of infants.In this study,Bacillus subtilis RIK1285 harboring AprE signal peptide(SP)was selected as the original strain for the production ofα-LA.It was found thatα-LA was identified in the pellet after ultrasonic disruption and centrifugation instead of in the fermentation supernatant.The original strain most likely only producedα-LA intracellular,but not extracellular.To improve the expression and secretion ofα-LA in RIK1285,a library of 173 homologous SPs from the B.subtilis 168 genome was fused with target LALBA gene in the pBE-S vector and expressed extracellularly in RIK1285.SP YjcN was determined to be the best signal peptide.Bands in supernatant were observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and purified by nickel column to calculate the highest yield signal peptide.In addition,different promoters(P_(aprE),P_(43),and P_(glv))were compared and applied.The results indicated that the strain RIK1285-pBE-P_(glv)-YjcN-LALBA had the highestα-LA yield,reaching 122.04μg/mL.This study demonstrates successful expression and secretion of humanα-LA in B.subtilis and establishes a foundation for simulating breast milk for infant formulas and developing bioengineered milk.

关键词： Bacillus subtilis Alpha-lactalbumin Bioengineering milk Signal peptide Promoter screening

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Celastrol regulates the oligomeric state and chaperone activity of 𝛼B-crystallin linked with protein homeostasis in the lens

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Fundamental Research 2024年第2期4卷 394-400页

作者： Huaxia Wang Qing Tian Ying Zhang Yibo Xi lidan Hu Ke Yao jingyuan li Xiangjun Chen Eye Center of the Second Affiliated Hospital Zhejiang University School of Medicine88 Jiefang RoadHangzhou 310009China Institute of Translational Medicine Zhejiang University School of Medicine268 Kaixuan RoadHangzhou 310020China. State Key Laboratory of Membrane Biology School of Life SciencesTsinghua UniversityBeijing 100084China The Children’s Hospital Zhejiang University School of MedicineNational Clinical Research Center for Child HealthHangzhou 310052China Zhejiang Province Key Laboratory of Quantum Technology and Device Department of PhysicsZhejiang UniversityZheda Road 38Hangzhou 310027China

Protein misfolding and aggregation are crucial pathogenic factors for cataracts,which are the leading cause of visual impairment worldwide.α-crystallin,as a small molecular chaperone,is involved in preventing protein misfolding and maintaining lens transparency.The chaperone activity of α-crystallin depends on its oligomeric state.Our previous work identified a natural compound,celastrol,which could regulate the oligomeric state of αB-crystallin.In this work,based on the UNcle and SEC analysis,we found that celastrol induced𝛼αB-crystallin to form large oligomers.Large oligomer formation enhanced the chaperone activity of αB-crystallin and prevented aggregation of the cataract-causing mutant αA3-G91del.The interactions between𝛼αB-crystallin and celastrol were detected by the FRET(Fluorescence Resonance Energy Transfer)technique,and verified by molecular docking.At least 9 binding patterns were recognized,and some binding sites covered the groove structure of αB-crystallin.Interestingly,αB-R120G,a cataract-causing mutation located at the groove structure,and celastrol can decrease the aggregates of αB-R120G.Overall,our results suggested celastrol not only promoted the formation of large αB-crystallin oligomers,which enhanced its chaperone activity,but also bound to the groove structure of its α-crystallin domain to maintain its structural stability.Celastrol might serve as a chemical and pharmacological chaperone for cataract treatment.

关键词： αB-crystallin Celastrol Interactions Oligomeric state Chaperone activity Structural stability

Biological function of miRNA-145-5p in angiotensin II induced renal inflammation

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BIOCELL 2024年第4期48卷 601-611页

作者： BIN li YUCHENG SHENG XIAOYING XU SHENGCUN WANG HONGYAN SONG jingyuan li HAONAN JI QINGHUA WANG XIAODI ZHOU LONGJU QI Department of Pediatrics Affiliated Hospital of Nantong UniversityNantong226001China Department of Science and Education Affiliated Nantong Hospitalof Nantong UniversityNantong226001China Laboratory Animal Center Nantong UniversityNantong226001China Department of Gynecology and Obstetrics and Department of Oncology Hai’an Hospital Affiliated to Nantong UniversityNantong226600China

Objective:Chronic kidney disease(CKD)is a progressive disorder characterized by intricate structural and functional alterations in the kidneys,attributable to diverse causative factors.Notably,the therapeutic promise of miR-145-5p in addressing renal pathologies has been discerned.This investigation seeks to elucidate the functional role of miR-145-5p in injured kidneys by subjecting human glomerular mesangial cells(HGMCs)to stimulation with Angiotensin II(AngII).Materials and Methods:Cellular viability and the levels of inﬂammatory mediators were evaluated utilizing Cell Counting Kit-8(CCK-8),quantitative real-time polymerase chain reaction(qRT-PCR),and western blot methodologies,both in the presence of AngII incubation and in scenarios of miR-145p overexpression and downregulation.Furthermore,the cell cycle dynamics were elucidated through Fluorescence-activated Cell Sorting(FACS)analysis.Results:AngII incubation induced an upregulation of miR-145-5p and inﬂammatory factors including Intercellular Adhesion Molecule 1(ICAM-1),Interleukin 6(IL-6),Interleukin 8(IL-8),and Interleukin 1β(IL-1β).Additionally,it elevated the expression of Cyclin A2,Cyclin D1,and the G2/M cell cycle ratio.Conversely,inhibition of miR-145-5p heightened the levels of inﬂammatory factors and cell cycle regulators induced by AngII incubation.Reduced expression of miR-145-5p correlated with a downregulation of Interleukin 10(IL-10)expression,concurrently promoting HGMC proliferation under AngII stimulation.Moreover,ectopic miR-145-5p expression demonstrated a reduction in inﬂammatory factors,cell cyclin regulators,G2/M cell cycle ratio,and overall proliferation.Conclusion:MiR-145-5p exhibited inhibitory effects on the inﬂammatory response and proliferation induced by Angiotensin II in HGMCs,showcasing its potential as a therapeutic avenue for the treatment of kidney injury.

关键词： miR-145-5p Kidney Angiotensin II Cell cycle Inflammation

POX1 regulates the formation of viable but non-culturable brewer’s yeast induced by iso-alpha acid from hops

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Food Science and Human Wellness 2024年

作者： Zengyan Wang Yang Xiao Xuchen li Zhenqing li Yan Wang Wei He Jiayang Wang li liu Ting Ding Pengdong Sun jingyuan li Yang Deng Shandong Technology Innovation Center of Special Food 4. Qingdao Special Food Research Institute Key Laboratory of Special Food Processing (Co-construction by Ministry and Province) Ministry of Agriculture Rural Affairs Qingdao Agricultural University School of Food Engineering Qingdao Institute of Technology College of Food Science and Engineering Qingdao Agricultural University Shandong Huifa Foodstuff Co. Ltd.

In this study， we utilized gene knockout and overexpression techniques to generate brewer’s yeast strains with either a deletion or overexpression of the POX1 gene. The strains studied included the parental strain， the POX1 deletion strain， and the POX1 overexpression strain. These strains were exposed to iso-alpha acid from hops at a concentration of 300 mg/L， leading to the induction of a viable but non-culturable (VBNC) state. Our results indicated that the silencing of the POX1 gene rendered brewer’s yeast cells unable to withstand the high concentration of iso-alpha acid stress， ultimately leading to cell death. Conversely， the overexpression of POX1 accelerated the transition of yeast cells into the VBNC state compared to the parental strain. Furthermore， we evaluated the levels of reactive oxygen species (ROS)， catalase (CAT) activity， superoxide dismutase (SOD) activity， glutathione reductase (GR) activity， and the mRNA expression of genes that regulate these enzymes (SYM1， CTA1， SOD1， and GLR1) in brewer’s yeast cells at three distinct stages: normal， short-term stress， and VBNC states. Based on these findings， it can be inferred that the formation of the VBNC state in brewer’s yeast is associated with the response to oxidative stress.

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Structural transition, electric transport, and electronic structures in the compressed trilayer nickelate LaNiO

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Science China(Physics,Mechanics & Astronomy) 2024年

作者： jingyuan li Cuiqun Chen Chaoxin Huang Yifeng Han Mengwu Huo Xing Huang Peiyue Ma Zhengyang Qiu Junfeng Chen Xunwu Hu Lan Chen Tao Xie Bing Shen Hualei Sun Daoxin Yao Meng Wang Center for Materials of the Universe School of Molecular Sciences Arizona State University Center for Neutron Science and Technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices School of Physics Sun Yat-sen University School of Sciences Sun Yat-sen University

Atomic structure and electronic band structure are fundamental properties for understanding the mechanism of superconductivity. Motivated by the discovery of pressure-induced high-temperature superconductivity at 80 K in the bilayer Ruddlesden-Popper nickelate La3Ni2O7, the atomic structure and electronic band structure of the trilayer nickelate La4Ni3O10under pressure up to 44.3 GPa are investigated. A structural transition from the monoclinic P21/a space group to the tetragonal I4/mmm around 12.6-13.4 GPa is identified, accompanied by a drop of resistance below 7 K. Density functional theory calculations suggest that the bonding state of Ni 3dz2orbital rises and crosses the Fermi level at high pressures, which may give rise to possible superconductivity observed in resistance under pressure in La4Ni3O10. The trilayer nickelate La4Ni3O10shows some similarities with the bilayer La3Ni2O7and has unique properties, providing a new platform to investigate the underlying mechanism of superconductivity in nickelates.

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Modeling the impact of awareness programs on the transmission dynamics of dengue and optimal control

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International Journal of Biomathematics 2023年第2期16卷 31-57页

作者： jingyuan li Hui Wan Mengfeng Sun Jiangsu Key Laboratory for NSLSCS School of Mathematical Sciences Nanjing Normal University Nanjing210023P.R.China Department of Mathematics Purdue University West LafayetteIN 47906USA

In this work,we first propose a mathematical model to study the impact of awareness programs on dengue transmission.The basic reproduction number Ro is derived.The existence and stability of equilibria are investigated.The uniform persistence is established when Ro is larger than one.Our results suggest that awareness programs have significant impacts on dengue transmission dynamics although they cannot affect Ro.When o is less than one,awareness programs can shorten the prevailing time effectively.When Ro is larger than one,awareness programs may destabilize the unique interior equilibrium and a stable periodic solution appears due to Hopf bifurcation.In particular,we find that the occurrence of Hopf bifurcation depends not only on the intensity of awareness programs but also on the level of Ro.Besides,large fuctuations in the number of infected individuals caused by the stable periodic solution may bring pressure on limited medical resources.Therefore,different from intuitive ideas,blindly increasing the intensity of awareness programs is not necessarily conducive to control the transmission of dengue.The decision-making department should decide to adopt different publicity strategies according to the current level of Ro.Finally,we consider the optimal control problem of the model and find the optimal control strategy corresponding to awareness programs by Pontryagin's Maximum Principle.The results manifest that the optimal control strategy can effectively mitigate the transmission of dengue.

关键词： Dengue awareness programs Hopf bifurcation uniform persistence optimal control

A hybrid network integrating convolution and transformer for thymoma segmentation

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Intelligent Medicine 2023年第3期3卷 164-172页

作者： jingyuan li Wenfang Sun Xiulong Feng Karen Mvon Deneen Wen Wang Guangbin Cui Yi Zhang Center for Brain Imaging School of Life Science and TechnologyXidian UniversityXi'anShaanxi 710126China International Joint Research Center for Advanced Medical Imaging and Intelligent Diagnosis and Treatment&Xi'an Key Laboratory of Intelligent Sensing and Regulation of trans-Scale life Information School of Life Science and TechnologyXidian UniversityXi'anShaanxi 710126China School of Aerospace Science and Technology Xidian UniversityXi'anShaanxi 710126China Department of Radiology Tangdu HospitalFourth Military Medical UniversityNo.4 Xinsi RoadXi'anShaanxi 710038China

Background Manual segmentation of thymoma is an onerous,labor-intensive,and subjective task for radiologists.Accordingly,the development of an automatic and efficient method for thymoma segmentation can be valuable for the early detection and diagnosis of this malignancy.Methods Three hundred and ten subjects were enrolled in this retrospective study and all underwent CECT scans.All the scans were manually labeled by four experienced radiologists.The successful application of convolution neural networks(CNNs)and Transformer in computer vision led us to propose a hybrid CNN–Transformer architecture,named transformer attention Net(TA-Net),that would allow the utilization of both local information from CNN features and the global information encoded by Transformers.U-Net was used as the basic structure and Transformers were inserted into convolution blocks in the encoder.In addition,attention gates were embedded in skip connections to highlight salient features.Comparison of the accuracy,intersection over Union(IoU),Dice score,and Boundary F1 contour matching score(BFScore)between the predicted segmentation and the manual labels were utilized to evaluate segmentation performance.Results For thymoma segmentation using TA-Net,the accuracy,Dice score,IoU,and BFScore were 92.49%,89.92%,83.80%,and 0.8945,respectively,and no significant differences were detected among tumor types and enhanced phases.Our proposed method achieved the best performance when compared with state-of-the-art methods.Conclusion The proposed method,which combines CNNs with Transformer,achives outstanding performance in thymoma segmentation compared with previous methods.TA-Net may provide consistent and reproducible delineation,thereby assisting radiologists in clinical applications.

关键词： Semantic segmentation Convolution neural network Transformer Attention mechanism Thymoma

Single-molecule force spectroscopy study of the effect of cigarette carcinogens on thrombomodulin–thrombin interaction

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Science Bulletin 2016年第15期61卷 1187-1194页

作者： Jianli liu Xuejie Zhang Xiaofeng Wang li Xu jingyuan li Xiaohong Fang Key Laboratory of Molecular Nanostructure and Nanotechnology Institute of Chemistry Chinese Academy ofSciences Beijing 100190 China Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety Institute of High Energy Physics Chinese Academyof Sciences Beijing 100049 China

Exposure to cigarette smoke is a major risk factor for cancer and cardiovascular disease. Thrombosis is regarded as the main reason for smoking-related cardiovascular disease. However, the detail mechanism of how smoking promotes thrombosis is not fully understood. In this work, we investigated the impacts of one major cigarette carcinogens 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone(NNK) as well as its metabolite4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol(NNAL)on a key process in thrombosis regulation: thrombin–thrombomodulin(TM) binding. Atomic force microscopy based single-molecule force spectroscopy was applied to measure both in vitro and in vivo binding force of thrombin to TM in the absence and presence of NNK and NNAL respectively. The results revealed that NNK and NNAL can reduce the binding probability of TM and thrombin. The inhibition effect and underlying mechanism was further studied by molecular simulation. As indicated by our results, the cigarette carcinogens could cause a higher risk of thrombosis through the disruption of TM–thrombin interaction.

关键词：血栓调节蛋白单分子力谱香烟烟雾致癌物质相互作用凝血酶原子力显微镜技术心血管疾病

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