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Improving Mechanical Properties and Energy Absorption of Additive Manufacturing Lattice Structure by Struts’Node Strengthening

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Acta Mechanica Solida Sinica 2022年第6期35卷 1004-1020页

作者： dongming li Ruixian Qin Jianxin Xu Junxian Zhou Bingzhi Chen School of Mechanical Engineering Dalian Jiaotong UniversityDalian116028China School of Locomotive and Rolling Stock Engineering Dalian Jiaotong UniversityDalian116028China School of Materials Science and Engineering Dalian Jiaotong UniversityDalian116028China

The lattice structure has unique performance and superior deformation behavior,which effectively stimulates the design and application of new lattice structures.The development of additive manufacturing technology makes it easy and efficient to manufacture complex lattice structures.However,it has been found that excessively high stress concentration exists at the struts’nodes during the compression of lattice structure.Therefore,three node strengthening strategies were proposed to reduce stress concentration,which were adding fillet at nodes,using circular arc transition and changing the angle of nodes.Firstly,lattice structures were manufactured by selective laser melting technique.The surface morphology of the lattice structures was observed by scanning electron microscopy.Then,the stress distribution and deformation mechanism of different lattice structures were investigated by quasi-static compression experiments and numerical simulation.Finally,the Gibson–Ashby model was adopted to predict lattice structures’modulus and strength.And the energy absorptions of different structures were compared.The results revealed that the deformation mode of the optimized structures changed from shear failure to layer-by-layer collapse.Compared with the hourglass lattice structure and gradient lattice structure,the mechanical properties of curve lattice structure were improved the most.

关键词： Node strengthening Stress concentration Lattice structure Selective laser melting Deformation mode

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Hibernation with rhythmicity:the circadian clock and hormonal adaptations of the hibernating Asiatic toads(Bufo gargarizans)

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Integrative Zoology 2022年第4期17卷 656-669页

作者： Zhigang XIE Ibrahim M.AHMAD lirong ZUO Feng XIAO Yongpeng WANG dongming li Zhejiang Academy of Agricultural Sciences HangzhouChina College of Chemistry and life Science Zhejiang Normal UniversityJinhuaChina Ministry of Education Key Laboratory of Molecular and Cellular Biology Key Laboratory of Animal PhysiologyBiochemistry and Molecular Biology of Hebei ProvinceCollege of Life SciencesHebei Normal UniversityShijiazhuangChina

Hibernation is one of the fundamental strategies in response to cold environmental temperatures.During hibernation,the endocrine and circadian systems ensure minimal expenditure of energy for survival.The circadian rhythms of key hormones,melatonin(MT),corticosterone(CORT),triiodothyronine(T3),and thyroxine(T4),and the underlying molecular regulatory mechanisms of hibernation have been well determined in mammals but not in ectotherms.Here,a terrestrial hibernating species,Asiatic toad(Bufo gargarizans),was employed to investigate the plasma CORT,MT,T3,and T4;and the retina,brain,and liver mRNA expression of the core clock genes,including circadian locomotor output cycles kaput(Clock),brain and muscle ARNT-like 1(Bmal1),cryptochrome(Cry)1 and 2,and period(Per)1 and 2,at 7-time points over a 24-h period under acute cold(1 day at 4℃),and hibernation(45 days at 4℃).Our results showed that the circadian rhythms of the core clock genes were rather unaffected by acute cold exposure in the retina,unlike the brain and liver.In contrast,during hibernation,the liver clock genes displayed significant circadian oscillations,while those in the retina and brain stopped ticking.Furthermore,plasma CORT expressed circadian oscillations in both groups,and T3 in acute cold exposure group,whereas T4 and MT did not.Our results reveal that the plasma CORT and the liver sustain rhythmicity when the brain was not,indicating that the liver clock along with the adrenal clock synergistically maintains the metabolic requirements to ensure basic survival in hibernating Asiatic toads.

关键词： Asiatic toad circadian rhythm clock genes cold exposure hibernation metabolic hormones

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Breath-by-breath measurement of exhaled ammonia by acetonemodifier positive photoionization ion mobility spectrometry via online dilution and purging sampling

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Journal of Pharmaceutical Analysis 2023年第4期13卷 412-420页

作者： Lu Wang Dandan Jiang Lei Hua Chuang Chen dongming li Weiguo Wang Yiqian Xu Qimu Yang Haiyang li Song Leng CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China Health Management Center The Second Affiliated Hospital of Dalian Medical UniversityDalian116023China University of Chinese Academy of Sciences Beijing100049China Dalian Key Laboratory for Online Analytical Instrumentation Dalian116023China Dalian Engineering Research Center of Breath Diagnostic Technology Dalian116023China

Exhaled ammonia(NH_(3))is an essential noninvasive biomarker for disease diagnosis.In this study,an acetone-modifier positive photoionization ion mobility spectrometry(AM-PIMS)method was developed for accurate qualitative and quantitative analysis of exhaled NH_(3)with high selectivity and sensitivity.Acetone was introduced into the drift tube along with the drift gas as a modifier,and the characteristic NH_(3)product ion peak of(C_(3)H_(6)O)_(4)NH_(4)^(+)(K_(0)=1.45 cm^(2)/V·s)was obtained through the ion-molecule reaction with acetone reactant ions(C_(3)H_(6)O)_(2)H^(+)(K_(0)=1.87 cm^(2)/V·s),which significantly increased the peak-to-peak resolution and improved the accuracy of exhaled NH_(3)qualitative identification.Moreover,the interference of high humidity and the memory effect of NH_(3)molecules were significantly reduced via online dilution and purging sampling,thus realizing breath-by-breath measurement.As a result,a wide quantitative range of 5.87-140.92μmol/L with a response time of 40 ms was achieved,and the exhaled NH_(3)profile could be synchronized with the concentration curve of exhaled CO_(2).Finally,the analytical capacity of AM-PIMS was demonstrated by measuring the exhaled NH_(3)of healthy subjects,demonstrating its great potential for clinical disease diagnosis.

关键词： Photoionization ion mobility spectrometry Acetone modifier Exhaled ammonia Breath analysis

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Comparative transcriptomic and metabolomic analysis reveals pectoralis highland adaptation across altitudinal songbirds

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Integrative Zoology 2022年第6期17卷 1162-1178页

作者： Ying XIONG Yan HAO Yalin CHENG liqing FAN Gang SONG dongming li Yanhua QU Fumin LEI Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina Key Laboratory of Forest Ecology in Tibet Plateau of Ministry of Education Institute of Tibet Plateau EcologyTibet Agriculture&Animal Husbandry UniversityNyingchiChina Key Laboratory of Animal Physiology Biochemistry and Molecular Biology of Hebei ProvinceCollege of Life SciencesHebei Normal UniversityShijiazhuangChina Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunmingChina

Pectoralis phenotypic variation plays a fundamental role in locomotion and thermogenesis in highland birds.How-ever,its regulatory and metabolic mechanisms remain enigmatic to date.Here,we integrated phenomic,tran-scriptomic,and metabolomic approaches to determine muscle variation and its underpinning mechanisms across altitudinal songbirds.Phenomics conﬁrmed that all highland birds had considerable increases in muscle oxidative capacity,capillarity,and mitochondrial abundance in our study.Correspondingly,transcriptomic analyses found that differentially expressed genes in phenotype-associated modules enriched for blood vessel,muscle structure development,and mitochondrial organization.Despite similar traits and functional enrichments across highland birds,different mechanisms drove their occurrence in high-altitude tree sparrow and 2 snowﬁnches.Importantly,a metabolic feature shared by all the 3 highland birds is the improvement in insulin sensitivity and glucose utilization through activating insulin signaling pathway,which is vital to increase muscle oxidative capacity and maintain metabolic homeostasis.Nevertheless,fatty acid biosynthesis and oxidation are enhanced in only 2 snowﬁnches which had a long evolutionary history on the high plateau,also differing from ketone body metabolism in recently introduced colonizer of the tree sparrow of the high plateau.Our study represents a vital contribution to reveal the regulatory and metabolic basis of pectoralis variation across altitudinal songbirds.

关键词： altitude gas chromatography–mass spectrometry hypoxia pectoralis RNA–seq

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Physiological but not morphological adjustments along latitudinal gradients in a human commensal species,the Eurasian tree sparrow

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Integrative Zoology 2023年第5期18卷 891-905页

作者： Qian ZHANG Mo li Yuan YIN Shiyong GE Danjie li Ibrahim M.AHMAD Ghulam NABI Yanfeng SUN Xu LUO dongming li Hebei Key Laboratory of Animal Physiology Biochemistry and Molecular BiologyCollege of Life SciencesHebei Normal UniversityShijiazhuangChina Key Laboratory for ConservingWildlife with Small Populations in Yunnan Faculty of Biodiversity and ConservationSouthwest Forestry UniversityKunmingChina Ocean College Hebei Agricultural UniversityQinhuangdaoChina Hebei Collaborative Innovation Center for Eco-Environment Hebei Normal UniversityShijiazhuangChina

Human commensal species take advantage of anthropogenic conditions that are less likely to be challenged by the selective pressures of natural environments.Their morphological and physiological phenotypes can therefore dissociate from habitat characteristics.Understanding how these species adjust their morphological and physiological traits across latitudinal gradients is fundamental to uncovering the eco-physiological strategies underlying coping mechanisms.Here,we studied morphological traits in breeding Eurasian tree sparrows(ETSs;Passer montanus)among low-latitude(Yunnan and Hunan)and middle-latitude(Hebei)localities in China.We then compared body mass;lengths of bill,tarsometatarsus,wing,total body,and tail feather;and baseline and capture stress-induced levels of plasma corticosterone(CORT)and the metabolites including glucose(Glu),total triglyceride(TG),free fatty acid(FFA),total protein,and uric acid(UA).None of the measured morphological parameters varied with latitude except in the Hunan population,which demonstrated longer bills than those in other populations.Stress-induced CORT levels significantly exceeded baseline levels and decreased with increasing latitude,but total integrated CORT levels did not vary with latitude.Capture stress-induced significantly increased Glu levels and decreased TG levels,independent of site.However,the Hunan population had significantly higher baseline CORT,baseline and stress-induced FFA levels,but lower UA levels,which differed from other populations.Our results suggest that rather than morphological adjustments,physiological adjustments are mainly involved in coping mechanisms for middle-latitude adaptation in ETSs.It is worth investigating whether other avian species also exhibit such dissociation from external morphological designs while depending on physiological adjustments.

关键词： capture stress corticosterone human commensal species latitudinal gradients plasma metabolites

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Effects of constant light and dark conditions on the locomotor activity,body mass,and body temperature rhythms of Eurasian Tree Sparrows(Passer montanus)

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Avian Research 2023年第3期14卷 435-442页

作者： lirong Zuo Ibrahim MAhmad Yuanyuan liu limin Wang Shu Fang dongming li Hebei Key Laboratory of Animal Physiology Biochemistry and Molecular BiologyCollege of Life SciencesHebei Normal UniversityShijiazhuang050024Hebei ProvinceChina Hebei Collaborative Innovation Center for Eco-Environment Hebei Normal UniversityShijiazhuang050024China

light is an essential environmental cue influencing the endogenous circadian clocks that regulate behavioral and physiological processes in animals.Despite extensive research on the circadian rhythms of avian behavior and physiology,the mechanisms by which they adapt and adjust to abnormal photoperiod conditions,such as artificial light,have yet to be fully elucidated.Here,the circadian rhythms of the body mass,activity,and core and peripheral body temperatures of the Eurasian Tree Sparrow(Passer montanus,ETS)-a diurnal passerine-were examined under three different lighting conditions:constant light(LL),constant darkness(DD),and normal light-dark cycles(LD).Our results showed that the activity,body mass,core,tarsometatarsus,and eye temperatures of the ETSs varied significantly with treatment,time,and the interaction between treatment and time;however,there was no significant change in body mass in response to the interaction between time and treatment.Under LD conditions,the ETSs exhibited significant circadian rhythms in activity and core,tarsometatarsus,and eye temperatures.Under LL conditions,only the core temperature exhibited significant rhythmicity.Under DD conditions,there were no significant circadian rhythms in activity,body mass,and eye temperature;however,the core and tarsometatarsus temperatures remained rhythmic.Our results indicate that the core body temperature rhythm of ETS is endogenous and can be maintained under abnormal photoperiods.In contrast,the activity and body surface temperature,uncoupled from the core body temperature under abnormal photoperiod conditions,strongly depend on light.These results differ from those of other diurnal avian species,suggesting a unique coping mechanism of ETS in response to an abnormal photoperiod.

关键词： Eurasian Tree Sparrow Activity Body mass Body temperature Circadian rhythm

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OsRLR4 binds to the OsAUX1 promoter to negatively regulate primary root development in rice

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Journal of Integrative Plant Biology 2022年第1期64卷 118-134页

作者： Chendong Sun dongming li Zhenyu Gao Lei Gao lianguang Shang Mei Wang Jiyue Qiao Shilin Ding Chuanyou li Markus Geisler Dean Jiang Yanhua Qi Qian Qian Key Laboratory of Herbage&Endemic Crop Biology of Ministry of Education Inner Mongolia Key Laboratory of Herbage&Endemic Crop BiotechnologySchool of Life SciencesInner Mongolia UniversityHohhot 010000China State Key Laboratory of Plant Physiology and Biochemistry College of Life SciencesZhejiang UniversityHangzhou 310058China The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province College of Advanced Agricultural SciencesZhejiang Agriculture and Forestry UniversityLin'an Hangzhou 311300China State Key Laboratory of Rice Biology China National Rice Research InstituteChinese Academy of Agricultural SciencesHangzhou 310006China College of life Sciences and Oceanography Guangdong Provincial Key Laboratory for Plant EpigeneticsShenzhen UniversityShenzhenChina Agricultural Genomics Institute at Shenzhen Chinese Academy of Agricultural SciencesShenzhen 518120China State Key Laboratory of Plant Genomics National Center for Plant Gene ResearchInstitute of Genetics and Developmental BiologyThe Chinese Academy of SciencesBeijing 100101China Department of Biology University of FribourgFribourg CH-1700Switzerland

Root architecture is one of the most important agronomic traits that determines rice crop yield. The primary root(PR) absorbs mineral nutrients and provides mechanical support;however, the molecular mechanisms of PR elongation remain unclear in rice. Here, the two loss-of-function T-DNA insertion mutants of root length regulator 4(Os RLR4), osrlr4-1 and osrlr4-2 with longer PR, and three Os RLR4 overexpression lines, OE-Os RLR4-1/-2/-3 with shorter PR compared to the wild type/Hwayoung(WT/HY), were identified. Os RLR4 isone of five members of the PRAF subfamily of the regulator chromosome condensation1(RCC1) family. Phylogenetic analysis of Os RLR4 from wild and cultivated rice indicated that it is under selective sweeps, suggesting its potential role in domestication. Os RLR4 controls PR development by regulating auxin accumulation in the PR tip and thus the root apical meristem activity. A series of biochemical and genetic analyses demonstrated that Os RLR4 functions directly upstream of the auxin transporter Os AUX1. Moreover, Os RLR4 interacts with the TRITHORAX-like protein Os Trx1 to promote H3 K4 me3 deposition at the Os AUX1 promoter, thus altering its transcription level. This work provides insight into the cooperation of auxin and epigenetic modifications in regulating root architecture and provides a genetic resource for plant architecture breeding.

关键词： auxin transporter primary root development regulator chromosome condensation 1 rice root length regulator

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Seasonal variations in gonad morphology and hypothalamic GnRH-I and GnIH in Eurasian Tree Sparrow,a multi-brooded passerine

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Avian Research 2022年第3期13卷 369-378页

作者： limin Wang Ghulam Nabi li Zhang Dan liu Mo li Juyong li Kaixin Shi Ibrahim M.Ahmad Yuefeng Wu John C.Wingfield dongming li Ministry of Education Key Laboratory of Molecular and Cellular Biology Key Laboratory of Animal PhysiologyBiochemistry and Molecular Biology of Hebei ProvinceCollege of Life SciencesHebei Normal UniversityShijiazhuang050024China Department of Neurobiology Physiology and BehaviorUniversity of Californi1DavisCAUSA

The hypothalamic-pituitary-gonadal(HPG)axis ubiquitously regulates seasonal reproduction,following the rhythmicity of a suite of environmental cues.Birds display prominent seasonal variations in gonad size regulated by two hypothalamic peptides,gonadotropin-releasing hormone-1(GnRH-I)and gonadotropin-inhibiting hormone(GnIH).How multi-brooded avian species adjust GnRH-I and GnIH to regulate gonadal morphology seasonally remains largely unknown.Here,we studied the variations in the hypothalamic immunoreactivity(ir)of GnRH-I and GnIH,gonadal proliferation,and apoptosis in a typical multi-brooded species,the Eurasian Tree Sparrow(Passer montanus),across the pre-breeding(PB),first breeding(FB),second breeding(SB),pre-basic molt(PM),and wintering stages(WS).Our results showed that both sexes had higher preoptic area(POA)-GnRH-I-ir but lower paraventricular nucleus(PVN)-GnIH-ir neurons during the breeding stages(FB and SB)relative to other life-history stages,with no significant differences between two broods.The testes and ovaries were significantly larger during the breeding stages.Testicular volume increased during the two broods due to anincreased diameter of seminiferous tubules.Furthermore,there were more testicular apoptotic cells in PB and WS stages than in breeding stages,and in PB stage than in PM stage.Males had higher POA-GnRH-I expression than females during the breeding stages,but both sexes had comparable PVN-GnIH expression throughout the annual cycle.Both sexes of the sparrows may undergo a similar pattern of life-history stage-dependent variation in the hypothalamic GnRH-I,GnIH,and gonadal morphology,except that during breeding stages,males may display higher expression of POA-GnRH-I relative to females.The higher expression of POA-GnRH-I-ir in breeding male sparrows may be critical for male-dependent parental care.

关键词： Eurasian Tree Sparrow Gonads Hypothalamus Reproduction Seasonality

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More than a simple egg:Underlying mechanisms of cold tolerance in avian embryos

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Avian Research 2023年第2期14卷 267-280页

作者： Ibrahim M.Ahmad dongming li Hebei Key Laboratory of Animal Physiology Biochemistry and Molecular BiologyCollege of Life SciencesHebei Normal UniversityShijiazhuang050024China Hebei Collaborative Innovation Center for Eco-Environment Hebei Normal UniversityShijiazhuang050024China

Avian embryos,which develop within eggs,exhibit remarkable tolerance to extremely low temperatures.Despite being a common trait among all birds,the mechanisms underlying this cold tolerance in avian embryos remain largely unknown.To gain a better understanding of this phenomenon and the coping mechanisms involved,we reviewed the literature on severe cold tolerance in embryos of both wild and domestic birds.We found that embryos of different bird orders exhibit tolerance to severe cold during their development.In response to cold stress,embryos slow down their heartbeat rates and metabolism.In severe cold temperatures,embryos can suspend these processes,entering a torpid-like state of cardiac arrest.To compensate for these developmental delays,embryos extend their regular incubation periods.Depending on their embryonic age,embryos of all bird species can tolerate acute severe cold regimes;only a few tolerate chronic severe cold regimes.We also discussed various extrinsic and intrinsic factors that affect the tolerance of bird embryos to low temperatures before and after incubation.Cold tolerance appears to be a heritable trait shared by wild and domestic embryos of all bird classes,regardless of egg size or development(altricial/precocial).Driven by environmental variability,cold tolerance in avian embryos is an optimal physiological and ecological strategy to mitigate the adverse effects of cold conditions on their development in response to fluctuating environmental temperatures.

关键词： Acute cold tolerance Avian embryo Chronic cold tolerance Embryonic development Hatching success Incubation period

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数字技术赋能城乡义务教育一体化发展路径研究——数字技术促进乡村教育高质量发展

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电化教育研究 2024年第3期45卷 39-45页

作者：李建珍李东明西北师范大学教育技术学院甘肃兰州730070 南京工业大学现代教育中心江苏南京211800

城乡义务教育一体化发展是党中央、国务院促进教育公平和教育事业协调发展的重大决策。2021年底,尽管全国2895个县级行政单位均通过了国家义务教育基本均衡发展督导评估,但是乡村地区仍存在师生流失、学校萎缩、教育教学条件相对滞后、... 详细信息

城乡义务教育一体化发展是党中央、国务院促进教育公平和教育事业协调发展的重大决策。2021年底,尽管全国2895个县级行政单位均通过了国家义务教育基本均衡发展督导评估,但是乡村地区仍存在师生流失、学校萎缩、教育教学条件相对滞后、教育资源配置不足等问题。文章通过文献和调查研究,分析了城乡义务教育一体化演进中存在的问题,并在数字技术赋能机理分析的基础上,主要针对城乡义务教育一体化发展中政策落实不到位、教育质量低下、乡村教师专业发展薄弱、工学矛盾和数字鸿沟等根本性问题,从教育数字化政策的顶层设计、结对帮扶、国家和地方中小学智慧教育平台应用、以校为本的教师培训、智能终端和数字化教学辅助工具完善等层面,提出了数字技术赋能城乡义务教育一体化发展的路径。

关键词：数字技术义务教育乡村教育教育均衡教育高质量发展

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