Due to the small size,active mobility,and intrinsic softness,miniature soft robots hold promising po-tentials in reaching the deep region inside living bodies otherwise inaccessible with compelling agility,adaptabilit...Due to the small size,active mobility,and intrinsic softness,miniature soft robots hold promising po-tentials in reaching the deep region inside living bodies otherwise inaccessible with compelling agility,adaptability and safety.Various materials and actuation strategies have been developed for creating soft robots,among which,ferromagnetic soft materials that self-actuate in response to external magnetic fields have attracted worldwide attention due to their remote controllability and excellent compatibil-ity with biological tissues.This review presents comprehensive and systematic research advancements in the design,fabrication,and applications of ferromagnetic soft materials for miniature robots,providing in-sights into their potential use in biomedical fields and beyond.The programming strategies of ferromag-netic soft materials are summarized and classified,including mold-assisted programming,3D printing-assisted programming,microassembly-assisted programming,and magnetization reprogramming.Each approach possesses unique advantages in manipulating the magnetic responsiveness of ferromagnetic soft materials to achieve outstanding actuation and deformation performances.We then discuss the biomedi-cal applications of ferromagnetic soft material-based soft robots(e.g.,minimally invasive surgery,targeted delivery,and tissue engineering),highlighting their potentials in revolutionizing biomedical technologies.This review also points out the current challenges and provides insights into future research directions,which we hope can serve as a useful reference for the development of next-generation adaptive miniature robots.展开更多
Underwater robots have emerged as key tools for marine exploration because of their unique ability to traverse and navigate underwater regions,which pose challenges or dangers to human expeditions.Miniature underwater...Underwater robots have emerged as key tools for marine exploration because of their unique ability to traverse and navigate underwater regions,which pose challenges or dangers to human expeditions.Miniature underwater robots are widely employed in marine science,resource surveys,seabed geological investigations,and marine life observations,owing to their compact size,minimal noise,and agile move-ment.In recent years,researchers have developed diverse miniature underwater robots inspired by bion-ics and other disciplines,leading to many landmark achievements such as centimeter-level wireless control,movement speeds up to hundreds of millimeters per second,underwater three-dimensional motion capabilities,robot swarms,and underwater operation robots.This article offers an overview of the actuation methods and locomotion patterns utilized by miniature underwater robots and assesses the advantages and disadvantages of each method.Furthermore,the challenges confronting currently available miniature underwater robots are summarized,and future development trends are explored.展开更多
Inspired by bacterial motility mechanisms,Magnetic Helical Miniature Robots(MHMRs)exhibit promising applications in biomedical fields due to their efficient locomotion and compatibility with biological tissues.In this...Inspired by bacterial motility mechanisms,Magnetic Helical Miniature Robots(MHMRs)exhibit promising applications in biomedical fields due to their efficient locomotion and compatibility with biological tissues.In this review,we systematically survey the basics of MHMRs,from propulsion mechanism,magnetization and control methods to biomedical applications,aiming to provide readers with an easily understandable overview and fundamental knowledge on implementing MHMRs.The MHMRs are actuated by rotating magnetic fields,achieving steering and rotation through magnetic torque,and converting rotation into forward motion through the helical structure.Magnetization methods for MHMRs are reviewed into three types:attaching magnets,magnetic coatings,and magnetic powder doping.Additionally,this review discusses the control methods for MHMRs,covering imaging techniques,path tracking control—including classical control algorithms and increasingly popular learning-based methods,and swarm control.Subsequently,a comprehensive survey is conducted on the biomedical applications of MHMRs in the treatment of vascular diseases,drug delivery,cell delivery,and their integration with catheters.We finally provide a perspective about future challenges in MHMR research,including enhancing functional design capabilities,developing swarm-assisted independent control mechanisms,refining in vivo imaging techniques,and ensuring robust biocompatibility for safe medical use.展开更多
This overview firstly introduces the state-of-the-art research progress in length scale-related fatigue performance of conventionally-fabricated metals evaluated by miniature specimens. Some key factors for size effec...This overview firstly introduces the state-of-the-art research progress in length scale-related fatigue performance of conventionally-fabricated metals evaluated by miniature specimens. Some key factors for size effects sensitive to microstructures including the specimen thickness, grain size and a ratio between them are highlighted to summarize some general rules for size effects. Then, ongoing research progress and new challenges in evaluating the fatigue performance of additive manufactured parts controlled by location-specific defects, microstructure heterogeneities as well as mechanical anisotropy using miniature specimen testing technique are discussed and addressed. Finally, a potential roadmap to establish a data-driven evaluation platform based on a large number of miniature specimen-based experiment data,theoretical computations and the ’big data’ analysis with machine learning is proposed. It is expected that this overview would provide a novel strategy for the realistic evaluation and fast qualification of fatigue properties of additive manufactured parts we have been facing to.展开更多
Alternative splicing is a cellular mechanism in eukaryotes that results in considerable diversity ofgene products. It plays an important role in several diseases and cellular signal regulation. Heat stress is a major ...Alternative splicing is a cellular mechanism in eukaryotes that results in considerable diversity ofgene products. It plays an important role in several diseases and cellular signal regulation. Heat stress is a major factor that induces immunosuppression in pigs. Little is known about the correlation between alternative splicing and heat stress in pigs. Therefore, this study aimed to clone, sequence and quantify the alternative splicing variant of toll-like receptor 4 （TLR4） in Bama miniature pigs （Sus scrofa domestica） following exposure to heat stress. The results showed that the second exon of TLR4 was spliced and 167 bp shorter in the alternative splicing variant, and the protein was putatively identified as a type of truncated membrane protein consisting of extramembrane, transmembrane and intramembrane regions lacking a signal peptide. Further, it was not a non- classical secretory protein. Five potential reference genes were screened for their potential as reliable standards to quantify the expression of TLR4 alternative spliced variants by real-time quantitative reverse-transcriptase polymerase chain reaction （qRT-PCR）. The stability of these reference genes was ranked using the geNorm and NormFinder programs, and ribosomal protein L4 （RPL4） and TATA box-binding protein （TBP） were found to be the two genes showing the most stable expression in the in vitro cultured peripheral blood mononuclear ceils （PBMCs） during heat shock. The mRNA level of the TLR4 gene （both classical and spliced） in stressed pigs increased significantly （P〈0.05）. Further, the expression levels of the alternative spliced variant of TLR4 （TLR4-ASV） showed a 2-3 folds increase in heat-stressed PBMCs as compared to control pigs. The results of the present study suggested that heat shock might modulate the host immune response by regulating the expressions of TLR4 and its alternative splicing variant.展开更多
The miniature design technology is an important trend in space exploration.Mass spectrometer is used extensively in the space environment detection.The miniature ion mass spectrometer utilizes a 127° cylindrical ...The miniature design technology is an important trend in space exploration.Mass spectrometer is used extensively in the space environment detection.The miniature ion mass spectrometer utilizes a 127° cylindrical electrostatic analyzer accompanied with a Time of Flight(TOF)unit based on ultrathin carbon foil to measure the energy spectra and composition of space plasma.The Time of Flight technique has been used broadly in space plasma measurement.A new type of miniature method for the ion mass spectrometer is introduced.The total mass of the instrument is1.8 kg and the total power consumption is 2.0 W.The calibration results show that the energy measurement range is 8.71~43550eV,the energy resolution is 1.86%and the ion mass from 1 amu(1 amu= 1.67 × 10^(-27)kg) to 58 amu can be resolved by the miniature mass spectrometer.The miniature ion mass spectrometer also has a potential to be increased in the field of view by an electrostatic deflecting system to extend its application in space plasma detection.The miniature ion mass spectrometer has been selected for pre-study of Chinese Strategic Priority Research Program on Space Science.展开更多
With outstanding analytical performance and portability, miniature mass spectrometer is one of the most powerful tools for in-situ analysis. The miniaturization of mass spectrometers has lasted for more than ten years...With outstanding analytical performance and portability, miniature mass spectrometer is one of the most powerful tools for in-situ analysis. The miniaturization of mass spectrometers has lasted for more than ten years, during which a number of miniature mass spectrometers employing different techniques have been developed. Small-in-size, working at relatively high pressure region and capable of performing tandem mass spectrometry, ion trap is the most widely used mass analyzer in miniature mass spectrometer systems. The recent development of miniature ion trap mass spectrometer systems in the last ten years was reviewed in this paper. These instruments adopt different atmospheric pressure interfaces （APIs）, which are membrane inlets （MIs）, discontinuous atmospheric pressure interface （DAPI） and continuous atmospheric pressure interface （CAPI）. This review emphasizes on the mini mass spectrometry （MS） system that can be handheld by one person, but not the field-able ones that are too large to be hand-portable.展开更多
Summary： Somatic cell nucleus transfer （SCNT） has been considered the most effective method for conserving endangered animals and expanding the quantity of adult animal models. Bama miniature pigs are genetically s...Summary： Somatic cell nucleus transfer （SCNT） has been considered the most effective method for conserving endangered animals and expanding the quantity of adult animal models. Bama miniature pigs are genetically stable and share similar biological features to humans. These pigs have been used to establish animal models for human diseases, and for many other applications. However, there is a pan- city of studies on the effect of ear fibroblasts derived from different age of adult Bama miniature pigs on nucleus transfer （NT）. The present study examined the NT efficiency of ear fibroblasts from fetal, new- born, 1-, 2-, 4-, 6-, 12-month-old miniature pigs by using trypan blue staining, flow cytometry and NT technique, etc., and the cell biological function and SCNT efficiency were compared between groups. The results showed that ear fibroblasts grew well after passage in each group. Spindle-shaped cells ini- tially predominated, and gradually declined with increase of culture time and replaced by polygonal cells. Irregular cell growth occurred in the 2-month-old group and the elder groups. The growth curves of the ear fibroblasts were ＂S-shaped＂ in different age groups. The cell proliferation of postnatal ear fi- broblasts, especially those from 2-, 4-, 6-, 12-month-old miniature pigs was significantly different from that of fetus ear fibroblasts （P〈0.05 or P〈0.01）. Two-month- and 4-month-old ear fibroblasts had a sig- nificantly higher proportion of G1 stage cells （85% to 91%） than those at 6 and 12 months （66% to 74%, P〈0.01）. The blastocyst rate of reconstructed embryos originating from newborn, 1-, 2-, 4-month-old donor pigs was 6.06% to 7.69% with no significant difference from that in fetus fibroblast group （8.06%）. It was concluded that 〈4-month-old adult Bama miniature pigs represent a better donor cell resource than elder pigs.展开更多
In this study, we developed a computer program for automatic prediction of watering time point by considering the environmental factors such as solar radiation, air temperature and relative humidity based on the multi...In this study, we developed a computer program for automatic prediction of watering time point by considering the environmental factors such as solar radiation, air temperature and relative humidity based on the multiple linear regression equation of leaf area and Penman Method. The experiments were carried out for a year in two watering experimental plots, one of which was controlled by pF value, and the other by the computer program. After comparing the results of the two plots, the following findings were obtained. In the computer program plot, the observed and predicted values of both leaf area and evapotranspiration indicated significant correlation at the 1% level, which suggested that the computer program had high prediction accuracy. In addition, no significant difference was observed between the two experimental plots with respects to the plant height, plant diameter, leaf area, leaf number, fresh weight, and dry weight, which demonstrated that the plants in the computer program plot had normal growth. On the other hand, although the number of flower buds and flowering shoots showed higher values at the end of certain cultivations in the computer program plot than those in pF value plot, we proposed that it was due to the effect of cumulative daily solar radiation in the greenhouse, rather than the watering. Thus, we have reached the conclusion that the computer program for automatic prediction of watering time point developed by this study has high applicability in miniature pot rose production.展开更多
A sliding mode control design for a miniature unmanned helicopter is presented. The control objective is to let the helicopter track some predefined velocity and yaw trajectories. A new sliding mode control design met...A sliding mode control design for a miniature unmanned helicopter is presented. The control objective is to let the helicopter track some predefined velocity and yaw trajectories. A new sliding mode control design method is developed based on a linearized dynamic model. In order to facilitate the control design, the helicopter＇s dynamic model is divided into two subsystems,such as the longitudinal-lateral and the heading-heave subsystem. The proposed controller employs sliding mode control technique to compensate for the immeasurable flapping angles＇ dynamic effects and external disturbances. The global asymptotic stability（GAS） of the closed-loop system is proved by the Lyapunov based stability analysis. Numerical simulations demonstrate that the proposed controller can achieve superior tracking performance compared with the proportionalintegral-derivative（PID） and linear-quadratic regulator（LQR） cascaded controller in the presence of wind gust disturbances.展开更多
Skin grafting has been used as one of the most reliable tests to determine the genetic stability of laboratory animal such as mice and rats inbred line, but no identification of swine inbred lines by skin grafting has...Skin grafting has been used as one of the most reliable tests to determine the genetic stability of laboratory animal such as mice and rats inbred line, but no identification of swine inbred lines by skin grafting has been reported. At present, Wuzhishan miniature pig （WZSP） inbred line has acquired the F24 individuals in China. In order to verify whether WZSP inbred line had D^en cultivated successfully, allogeneic skin grafts and related research were performed on F20 individuals of WZSP inbreeding population, compared with a control group of autologous transplantation. We observed the transplant recipients＇ wounds, detected peripheral blood-related indicators interleukin-2, 4 and 10, CD4~ and CD8~ lymphocytes, and conducted hematoxylin-eosin （HE） and Masson＇s staining of skin to judge whether the immune rejection reactions occurred within 28 days after transplantation. Chr. 7 genomic heterozygosity of 48 WZSP individuals from F20 to F22 was analyzed by high-density single nucleotide polymorphism （SNP） chips （60 000 SNPs）. The result showed that there were no significant differences in graft skin, the plasma interleukin-2, 4, 10, CD4~ and CD8~, HE and Masson＇s staining results between the allograft and autograft groups, and no immune rejection occurred on the allograft group. We found that 11 genes in Chr. 7 of major histocompatibility complex （MHC） I and MHC II were homozygous which confirmed that immune antibody of the allograft and autograft groups were highly identical and also provided a theoretical basis to no immune rejection occurred on the allograft in the inbred WZSP. The result proved that the WZSP inbred line had been cultivated successfully for the first time in the world. The test methods also provide a scientific basis for the identification of swine and mammal inbred lines.展开更多
In industrial applications,climbing robots are widely used for climbing and detection of rough or smooth pipe surfaces.Inspired by the special claws of longicorn is that can crawl on rough surfaces and the array of ti...In industrial applications,climbing robots are widely used for climbing and detection of rough or smooth pipe surfaces.Inspired by the special claws of longicorn is that can crawl on rough surfaces and the array of tiny bristles of geckos that can crawl on smooth surfaces,a new type of wall-climbing robot for rough or smooth surfaces is proposed in this paper.The bionic palms of the robot are suggested with special bionic hooks inspired by the longicorn and bionic adhesive materials inspired by the gecko with a good performance on adhering on the surfaces.The special bionic hooks are manufactured by the 3D printing method and the bionic adhesive materials are made by the polymer print lithography technology.These two different bionic adhere accessory are used on the robot’s palm to achieve climbing on the different surfaces.This foldable climbing robot can not only bend its own body to accommodate the cylindrical contact surfaces of different diameters,but also crawl on vertical rough and smooth surfaces using their bionic palms.展开更多
Objective:To report vestibular evoked myogenic potentials from different recording sites(neck extensor or masseter muscles) in miniature pigs and rats.Methods:Potentials were recorded using 1000 Hz tone bursts from th...Objective:To report vestibular evoked myogenic potentials from different recording sites(neck extensor or masseter muscles) in miniature pigs and rats.Methods:Potentials were recorded using 1000 Hz tone bursts from the neck extensor muscle or masseter muscle in normal adult Bama miniature pigs and rats anesthetized with 3%pentobarbital sodium and Sumianxin Ⅱ.Results:At 80 dB SPL,the first positive wave(P wave) of VEMPs was recognizable in 58%of rats with a latency of 6.45±0.23 ms and an amplitude of 1.45±0.49 μV when recorded from the neck extensor muscle,and in 50%of rats with a latency of 6.38±0.34 ms and an amplitude of 1.57±0.35 μV when recorded from the masseter muscle.In miniature pigs,at the same stimulus intensity,P wave was recognizable in 58%of the animals with a latency of 7.65±0.64 ms and an amplitude of 1.66±0.34 μV when recorded from the neck extensor muscle,and in 50%of the animals with a latency of 7.65±0.64 ms and an amplitude of 0.31±0.28 μV when recorded from the masseter muscle.Conclusion:VEMP can be induced from both neck extensor and masseter muscles in the miniature pig and rat.For a given species,the site of recording affects P wave induction rate and amplitude but not latency.Consistency and repeatability analysis suggests that the masseter muscle is a better recording site in miniature pigs while the cervical extensor is a better recording site in rats.For a given recording site,both latency and amplitude of the P wave are slightly greater in miniature pigs than in rats.展开更多
An ultimate goal of neuroscience is to decipher the principles underlying neuronal information processing at the molecular,cellular,circuit,and system levels.The advent of miniature fluorescence microscopy has further...An ultimate goal of neuroscience is to decipher the principles underlying neuronal information processing at the molecular,cellular,circuit,and system levels.The advent of miniature fluorescence microscopy has furthered the quest by visualizing brain activities and structural dynamics in animals engaged in self-determined behaviors.In this brief review,we summarize recent advances in miniature fluorescence microscopy for neuroscience,focusing mostly on two mainstream solutions-miniature single-photon microscopy,and miniature two-photon microscopy.We discuss their technical advantages and limitations as well as unmet challenges for future improvement.Examples of preliminary applications are also presented to reflect on a new trend of brain imaging in experimental paradigms involving body movements,long and complex protocols,and even disease progression and aging.展开更多
The miniature pig is an optimal animal model for studying nervous system disease because of its physiologic and pathologic features. However, the rete mirabile composed of arteries and veins at the skull base limits t...The miniature pig is an optimal animal model for studying nervous system disease because of its physiologic and pathologic features. However, the rete mirabile composed of arteries and veins at the skull base limits their application as a model of ischemic stroke by middle cerebral artery occlusion. The present study investigated the possibility of establishing an ischemic stroke model in the miniature pig by blocking the skull base retia with sodium alginate microspheres. Three Bama miniature pigs were used. Using the monitor of C-arm X-ray machine, sodium aiginate microspheres （100-300 pm）, a novel embolic material, were injected through the femoral artery, aortic arch, common carotid artery, ascending pharyngeal artery and the retia. Results were evaluated using carotid arteriography, MRI, behavior observation and histology. The unilateral rete mirabile was completely blocked, resulting in disturbance in blood supply to the basal ganglia, astasia of the dght hind limb and salivation. MRI and hematoxylin-eosin staining showed an evident infarction focus in the basal ganglia. These findings indicate that sodium alginate microspheres are a suitable embolic material for blocking the skull base retia in miniature pigs to establish an ischemic stroke models.展开更多
Because of the size limitation of weld joints in different regions, the traditional standard bar specimen is not suitable to investigate the mechanical properties of weld joints. In this study, miniature specimens wer...Because of the size limitation of weld joints in different regions, the traditional standard bar specimen is not suitable to investigate the mechanical properties of weld joints. In this study, miniature specimens were extracted from specific regions(base metal, weld metal, and three heat-affected zones) of API X80 and X70 weld joints. Uniaxial tensile tests were conducted to obtain the mechanical properties of different regions, and then uniaxial ratcheting tests were conducted to investigate the ratcheting behaviors of the different regions under the same peak and nominal stresses. Under both the tensile tests and ratcheting tests, the weld joints exhibit heterogeneous results, such as different mechanical properties and ratcheting behaviors, which were region dependent. Furthermore, the yield strength and yield-to-tensile strength ratio contribute differently to the ratcheting response.展开更多
Coat color is an important characteristic of various breeds of domestic animal species.Variation in farm animal coat color is of considerable interest for concealment,communication and protection against solar radiat...Coat color is an important characteristic of various breeds of domestic animal species.Variation in farm animal coat color is of considerable interest for concealment,communication and protection against solar radiation（Slominski et al.,2004）.It also plays an important role in the regulation of physiological processes（Miyagi and Terai,2013）.展开更多
This article presents a miniature robotic plane meteorological sounding system (RPMSS), which consists of three major subsystems: a miniature robotic plane, an air-borne meteorological sounding and ?ight control sys...This article presents a miniature robotic plane meteorological sounding system (RPMSS), which consists of three major subsystems: a miniature robotic plane, an air-borne meteorological sounding and ?ight control system, and a ground-based system. Take-o? and landing of the miniature aircraft are guided by radio control, and the ?ight of the robotic plane along a pre-designed trajectory is automatically piloted by an onboard navigation system. The observed meteorological data as well as all ?ight information are sent back in real time to the ground, then displayed and recorded by the ground-based computer. The ground-based subsystem can also transmit instructions to the air-borne control subsystem. Good system performance has been demonstrated by more than 300 hours of ?ight for atmospheric sounding.展开更多
基金the National Key R&D Program of China(No.2023YFE0208700)National Natural Sci-ence Foundation of China(No.92163109 and 52072095)+7 种基金Shenzhen Science and Technology Program(No.RCJC20231211090000001,GXWD20231129101105001)the National Natural Science Foundation of China(No.52205590)the Natural Science Foundation of Jiangsu Province(No.BK20220834)the Start-up Research Fund of Southeast University(No.RF1028623098)the State Key Laboratory of Robotics and Systems(HIT)(No.SKLRS-2024-KF-11)National Natural Science Foundation of China(No.52202348)Guangdong Basic and Applied Basic Research Foundation(No.2023A1515011491)Shenzhen Science and Technology Program(Nos.GXWD20220818224716001,KJZD20231023100302006).
文摘Due to the small size,active mobility,and intrinsic softness,miniature soft robots hold promising po-tentials in reaching the deep region inside living bodies otherwise inaccessible with compelling agility,adaptability and safety.Various materials and actuation strategies have been developed for creating soft robots,among which,ferromagnetic soft materials that self-actuate in response to external magnetic fields have attracted worldwide attention due to their remote controllability and excellent compatibil-ity with biological tissues.This review presents comprehensive and systematic research advancements in the design,fabrication,and applications of ferromagnetic soft materials for miniature robots,providing in-sights into their potential use in biomedical fields and beyond.The programming strategies of ferromag-netic soft materials are summarized and classified,including mold-assisted programming,3D printing-assisted programming,microassembly-assisted programming,and magnetization reprogramming.Each approach possesses unique advantages in manipulating the magnetic responsiveness of ferromagnetic soft materials to achieve outstanding actuation and deformation performances.We then discuss the biomedi-cal applications of ferromagnetic soft material-based soft robots(e.g.,minimally invasive surgery,targeted delivery,and tissue engineering),highlighting their potentials in revolutionizing biomedical technologies.This review also points out the current challenges and provides insights into future research directions,which we hope can serve as a useful reference for the development of next-generation adaptive miniature robots.
基金supported by the Natural Science Foundation of Jiangsu Province,China(BK20220813)the Fundamental Research Funds for the Central Universities(2242023K40014).
文摘Underwater robots have emerged as key tools for marine exploration because of their unique ability to traverse and navigate underwater regions,which pose challenges or dangers to human expeditions.Miniature underwater robots are widely employed in marine science,resource surveys,seabed geological investigations,and marine life observations,owing to their compact size,minimal noise,and agile move-ment.In recent years,researchers have developed diverse miniature underwater robots inspired by bion-ics and other disciplines,leading to many landmark achievements such as centimeter-level wireless control,movement speeds up to hundreds of millimeters per second,underwater three-dimensional motion capabilities,robot swarms,and underwater operation robots.This article offers an overview of the actuation methods and locomotion patterns utilized by miniature underwater robots and assesses the advantages and disadvantages of each method.Furthermore,the challenges confronting currently available miniature underwater robots are summarized,and future development trends are explored.
基金the financial support from the Research Institute for Advanced Manufacturing(RIAM)of The Hong Kong Polytechnic University(project Nos.1-CD9F and 1-CDK3)the Research Grants Council(RGC)of Hong Kong(project Nos.25200424 and 15206223)+2 种基金the GuangDong Basic and Applied Basic Research Foundation(project No.2023A1515110709)the Startup fund(project No.1-BE9L)of the Hong Kong Polytechnic Universitysupported by grant from the Research Committee of the Hong Kong Polytechnic University under student account code RN5Y.
文摘Inspired by bacterial motility mechanisms,Magnetic Helical Miniature Robots(MHMRs)exhibit promising applications in biomedical fields due to their efficient locomotion and compatibility with biological tissues.In this review,we systematically survey the basics of MHMRs,from propulsion mechanism,magnetization and control methods to biomedical applications,aiming to provide readers with an easily understandable overview and fundamental knowledge on implementing MHMRs.The MHMRs are actuated by rotating magnetic fields,achieving steering and rotation through magnetic torque,and converting rotation into forward motion through the helical structure.Magnetization methods for MHMRs are reviewed into three types:attaching magnets,magnetic coatings,and magnetic powder doping.Additionally,this review discusses the control methods for MHMRs,covering imaging techniques,path tracking control—including classical control algorithms and increasingly popular learning-based methods,and swarm control.Subsequently,a comprehensive survey is conducted on the biomedical applications of MHMRs in the treatment of vascular diseases,drug delivery,cell delivery,and their integration with catheters.We finally provide a perspective about future challenges in MHMR research,including enhancing functional design capabilities,developing swarm-assisted independent control mechanisms,refining in vivo imaging techniques,and ensuring robust biocompatibility for safe medical use.
基金supported by the National Natural Science Foundation of China(NSFC,Grant Nos.51771207 and 51571199)
文摘This overview firstly introduces the state-of-the-art research progress in length scale-related fatigue performance of conventionally-fabricated metals evaluated by miniature specimens. Some key factors for size effects sensitive to microstructures including the specimen thickness, grain size and a ratio between them are highlighted to summarize some general rules for size effects. Then, ongoing research progress and new challenges in evaluating the fatigue performance of additive manufactured parts controlled by location-specific defects, microstructure heterogeneities as well as mechanical anisotropy using miniature specimen testing technique are discussed and addressed. Finally, a potential roadmap to establish a data-driven evaluation platform based on a large number of miniature specimen-based experiment data,theoretical computations and the ’big data’ analysis with machine learning is proposed. It is expected that this overview would provide a novel strategy for the realistic evaluation and fast qualification of fatigue properties of additive manufactured parts we have been facing to.
基金supported by grants from the National Natural Science Foundation of China (31101862)the China Postdoctor Science Foundation and Guangdong Ocean University Doctor Seed Grant, China (0712107)
文摘Alternative splicing is a cellular mechanism in eukaryotes that results in considerable diversity ofgene products. It plays an important role in several diseases and cellular signal regulation. Heat stress is a major factor that induces immunosuppression in pigs. Little is known about the correlation between alternative splicing and heat stress in pigs. Therefore, this study aimed to clone, sequence and quantify the alternative splicing variant of toll-like receptor 4 （TLR4） in Bama miniature pigs （Sus scrofa domestica） following exposure to heat stress. The results showed that the second exon of TLR4 was spliced and 167 bp shorter in the alternative splicing variant, and the protein was putatively identified as a type of truncated membrane protein consisting of extramembrane, transmembrane and intramembrane regions lacking a signal peptide. Further, it was not a non- classical secretory protein. Five potential reference genes were screened for their potential as reliable standards to quantify the expression of TLR4 alternative spliced variants by real-time quantitative reverse-transcriptase polymerase chain reaction （qRT-PCR）. The stability of these reference genes was ranked using the geNorm and NormFinder programs, and ribosomal protein L4 （RPL4） and TATA box-binding protein （TBP） were found to be the two genes showing the most stable expression in the in vitro cultured peripheral blood mononuclear ceils （PBMCs） during heat shock. The mRNA level of the TLR4 gene （both classical and spliced） in stressed pigs increased significantly （P〈0.05）. Further, the expression levels of the alternative spliced variant of TLR4 （TLR4-ASV） showed a 2-3 folds increase in heat-stressed PBMCs as compared to control pigs. The results of the present study suggested that heat shock might modulate the host immune response by regulating the expressions of TLR4 and its alternative splicing variant.
基金Supported by the Strategic Priority Research Program on Space Science,the Chinese Academy of Sciences(XDA04071700,XDA04060202)
文摘The miniature design technology is an important trend in space exploration.Mass spectrometer is used extensively in the space environment detection.The miniature ion mass spectrometer utilizes a 127° cylindrical electrostatic analyzer accompanied with a Time of Flight(TOF)unit based on ultrathin carbon foil to measure the energy spectra and composition of space plasma.The Time of Flight technique has been used broadly in space plasma measurement.A new type of miniature method for the ion mass spectrometer is introduced.The total mass of the instrument is1.8 kg and the total power consumption is 2.0 W.The calibration results show that the energy measurement range is 8.71~43550eV,the energy resolution is 1.86%and the ion mass from 1 amu(1 amu= 1.67 × 10^(-27)kg) to 58 amu can be resolved by the miniature mass spectrometer.The miniature ion mass spectrometer also has a potential to be increased in the field of view by an electrostatic deflecting system to extend its application in space plasma detection.The miniature ion mass spectrometer has been selected for pre-study of Chinese Strategic Priority Research Program on Space Science.
基金supported by the National Natural Science Foundation of China (Nos. 21475010, 61635003)Beijing Natural Science Foundation (No. 16L00065)State Key Laboratory Explosion Science and Technology (No. YBKT16-17)
文摘With outstanding analytical performance and portability, miniature mass spectrometer is one of the most powerful tools for in-situ analysis. The miniaturization of mass spectrometers has lasted for more than ten years, during which a number of miniature mass spectrometers employing different techniques have been developed. Small-in-size, working at relatively high pressure region and capable of performing tandem mass spectrometry, ion trap is the most widely used mass analyzer in miniature mass spectrometer systems. The recent development of miniature ion trap mass spectrometer systems in the last ten years was reviewed in this paper. These instruments adopt different atmospheric pressure interfaces （APIs）, which are membrane inlets （MIs）, discontinuous atmospheric pressure interface （DAPI） and continuous atmospheric pressure interface （CAPI）. This review emphasizes on the mini mass spectrometry （MS） system that can be handheld by one person, but not the field-able ones that are too large to be hand-portable.
基金supported by the grants from the National Natural Science Foundation of China(No.31000546)National High-tech Research & Development Program of China(863 Program)(No.2012AA020603)+1 种基金National Science and Technology Major Project of China(No.2014zx08009-003-006)Rongchang Youth Foundation and Fundamental Research Funds of Southwest University(No.XDJK2012C097)
文摘Summary： Somatic cell nucleus transfer （SCNT） has been considered the most effective method for conserving endangered animals and expanding the quantity of adult animal models. Bama miniature pigs are genetically stable and share similar biological features to humans. These pigs have been used to establish animal models for human diseases, and for many other applications. However, there is a pan- city of studies on the effect of ear fibroblasts derived from different age of adult Bama miniature pigs on nucleus transfer （NT）. The present study examined the NT efficiency of ear fibroblasts from fetal, new- born, 1-, 2-, 4-, 6-, 12-month-old miniature pigs by using trypan blue staining, flow cytometry and NT technique, etc., and the cell biological function and SCNT efficiency were compared between groups. The results showed that ear fibroblasts grew well after passage in each group. Spindle-shaped cells ini- tially predominated, and gradually declined with increase of culture time and replaced by polygonal cells. Irregular cell growth occurred in the 2-month-old group and the elder groups. The growth curves of the ear fibroblasts were ＂S-shaped＂ in different age groups. The cell proliferation of postnatal ear fi- broblasts, especially those from 2-, 4-, 6-, 12-month-old miniature pigs was significantly different from that of fetus ear fibroblasts （P〈0.05 or P〈0.01）. Two-month- and 4-month-old ear fibroblasts had a sig- nificantly higher proportion of G1 stage cells （85% to 91%） than those at 6 and 12 months （66% to 74%, P〈0.01）. The blastocyst rate of reconstructed embryos originating from newborn, 1-, 2-, 4-month-old donor pigs was 6.06% to 7.69% with no significant difference from that in fetus fibroblast group （8.06%）. It was concluded that 〈4-month-old adult Bama miniature pigs represent a better donor cell resource than elder pigs.
基金supported by the Science Founda-tion of Guangxi Zhuang Autonomous Region, China(0832002)
文摘In this study, we developed a computer program for automatic prediction of watering time point by considering the environmental factors such as solar radiation, air temperature and relative humidity based on the multiple linear regression equation of leaf area and Penman Method. The experiments were carried out for a year in two watering experimental plots, one of which was controlled by pF value, and the other by the computer program. After comparing the results of the two plots, the following findings were obtained. In the computer program plot, the observed and predicted values of both leaf area and evapotranspiration indicated significant correlation at the 1% level, which suggested that the computer program had high prediction accuracy. In addition, no significant difference was observed between the two experimental plots with respects to the plant height, plant diameter, leaf area, leaf number, fresh weight, and dry weight, which demonstrated that the plants in the computer program plot had normal growth. On the other hand, although the number of flower buds and flowering shoots showed higher values at the end of certain cultivations in the computer program plot than those in pF value plot, we proposed that it was due to the effect of cumulative daily solar radiation in the greenhouse, rather than the watering. Thus, we have reached the conclusion that the computer program for automatic prediction of watering time point developed by this study has high applicability in miniature pot rose production.
基金supported by the Natural Science Foundation of Tianjin(No.14JCZDJC31900)
文摘A sliding mode control design for a miniature unmanned helicopter is presented. The control objective is to let the helicopter track some predefined velocity and yaw trajectories. A new sliding mode control design method is developed based on a linearized dynamic model. In order to facilitate the control design, the helicopter＇s dynamic model is divided into two subsystems,such as the longitudinal-lateral and the heading-heave subsystem. The proposed controller employs sliding mode control technique to compensate for the immeasurable flapping angles＇ dynamic effects and external disturbances. The global asymptotic stability（GAS） of the closed-loop system is proved by the Lyapunov based stability analysis. Numerical simulations demonstrate that the proposed controller can achieve superior tracking performance compared with the proportionalintegral-derivative（PID） and linear-quadratic regulator（LQR） cascaded controller in the presence of wind gust disturbances.
基金supported by the National High Technology Research and Development Program of China (2012AA020603)the National Transgenic Major Project, China (2008ZX08012-002-05)the National Key Technoligy R&D Program of China (2012BA13904)
文摘Skin grafting has been used as one of the most reliable tests to determine the genetic stability of laboratory animal such as mice and rats inbred line, but no identification of swine inbred lines by skin grafting has been reported. At present, Wuzhishan miniature pig （WZSP） inbred line has acquired the F24 individuals in China. In order to verify whether WZSP inbred line had D^en cultivated successfully, allogeneic skin grafts and related research were performed on F20 individuals of WZSP inbreeding population, compared with a control group of autologous transplantation. We observed the transplant recipients＇ wounds, detected peripheral blood-related indicators interleukin-2, 4 and 10, CD4~ and CD8~ lymphocytes, and conducted hematoxylin-eosin （HE） and Masson＇s staining of skin to judge whether the immune rejection reactions occurred within 28 days after transplantation. Chr. 7 genomic heterozygosity of 48 WZSP individuals from F20 to F22 was analyzed by high-density single nucleotide polymorphism （SNP） chips （60 000 SNPs）. The result showed that there were no significant differences in graft skin, the plasma interleukin-2, 4, 10, CD4~ and CD8~, HE and Masson＇s staining results between the allograft and autograft groups, and no immune rejection occurred on the allograft group. We found that 11 genes in Chr. 7 of major histocompatibility complex （MHC） I and MHC II were homozygous which confirmed that immune antibody of the allograft and autograft groups were highly identical and also provided a theoretical basis to no immune rejection occurred on the allograft in the inbred WZSP. The result proved that the WZSP inbred line had been cultivated successfully for the first time in the world. The test methods also provide a scientific basis for the identification of swine and mammal inbred lines.
基金This research was supported by the National Natural Science Foundation of China(No.11774355).
文摘In industrial applications,climbing robots are widely used for climbing and detection of rough or smooth pipe surfaces.Inspired by the special claws of longicorn is that can crawl on rough surfaces and the array of tiny bristles of geckos that can crawl on smooth surfaces,a new type of wall-climbing robot for rough or smooth surfaces is proposed in this paper.The bionic palms of the robot are suggested with special bionic hooks inspired by the longicorn and bionic adhesive materials inspired by the gecko with a good performance on adhering on the surfaces.The special bionic hooks are manufactured by the 3D printing method and the bionic adhesive materials are made by the polymer print lithography technology.These two different bionic adhere accessory are used on the robot’s palm to achieve climbing on the different surfaces.This foldable climbing robot can not only bend its own body to accommodate the cylindrical contact surfaces of different diameters,but also crawl on vertical rough and smooth surfaces using their bionic palms.
基金supported by grants from the National Basic Research Program of China (973 Program)(#2012CB967900)National Natural Science Foundation of China (31300624,81470684)+3 种基金Postdoctoral Science Foundation of China (2015M571818)Six Major Categories of Talent (2014-WSN043,2011-WS-074)Innovation and Entrepreneurship Training Program for College Students in Jiangsu Province(201510313003Z,201510313003,KYLX14-1455)Clinic Medical Special Foundation of Jiangsu Province (b12014032)
文摘Objective:To report vestibular evoked myogenic potentials from different recording sites(neck extensor or masseter muscles) in miniature pigs and rats.Methods:Potentials were recorded using 1000 Hz tone bursts from the neck extensor muscle or masseter muscle in normal adult Bama miniature pigs and rats anesthetized with 3%pentobarbital sodium and Sumianxin Ⅱ.Results:At 80 dB SPL,the first positive wave(P wave) of VEMPs was recognizable in 58%of rats with a latency of 6.45±0.23 ms and an amplitude of 1.45±0.49 μV when recorded from the neck extensor muscle,and in 50%of rats with a latency of 6.38±0.34 ms and an amplitude of 1.57±0.35 μV when recorded from the masseter muscle.In miniature pigs,at the same stimulus intensity,P wave was recognizable in 58%of the animals with a latency of 7.65±0.64 ms and an amplitude of 1.66±0.34 μV when recorded from the neck extensor muscle,and in 50%of the animals with a latency of 7.65±0.64 ms and an amplitude of 0.31±0.28 μV when recorded from the masseter muscle.Conclusion:VEMP can be induced from both neck extensor and masseter muscles in the miniature pig and rat.For a given species,the site of recording affects P wave induction rate and amplitude but not latency.Consistency and repeatability analysis suggests that the masseter muscle is a better recording site in miniature pigs while the cervical extensor is a better recording site in rats.For a given recording site,both latency and amplitude of the P wave are slightly greater in miniature pigs than in rats.
基金We thank Dr.Zhe Zhao and Dr.Haitao Wu for helping with the experiments for Fig.2D,and Dr.Weijian Zong for discussion.This work was supported by grants from the National Natural Science Foundation of China(31327901,31570839,61975002,31830036,31821091,and 8182780030)the Major State Basic Research Program of China(2016 YFA0500400 and 2016YFA0500403)and the National Postdoctoral Program for Innovative Talents of China(BX20190011).
文摘An ultimate goal of neuroscience is to decipher the principles underlying neuronal information processing at the molecular,cellular,circuit,and system levels.The advent of miniature fluorescence microscopy has furthered the quest by visualizing brain activities and structural dynamics in animals engaged in self-determined behaviors.In this brief review,we summarize recent advances in miniature fluorescence microscopy for neuroscience,focusing mostly on two mainstream solutions-miniature single-photon microscopy,and miniature two-photon microscopy.We discuss their technical advantages and limitations as well as unmet challenges for future improvement.Examples of preliminary applications are also presented to reflect on a new trend of brain imaging in experimental paradigms involving body movements,long and complex protocols,and even disease progression and aging.
基金supported by the Science and Technology Support Program of Beijing Science and Technology Committee,No.Z101107052210004
文摘The miniature pig is an optimal animal model for studying nervous system disease because of its physiologic and pathologic features. However, the rete mirabile composed of arteries and veins at the skull base limits their application as a model of ischemic stroke by middle cerebral artery occlusion. The present study investigated the possibility of establishing an ischemic stroke model in the miniature pig by blocking the skull base retia with sodium alginate microspheres. Three Bama miniature pigs were used. Using the monitor of C-arm X-ray machine, sodium aiginate microspheres （100-300 pm）, a novel embolic material, were injected through the femoral artery, aortic arch, common carotid artery, ascending pharyngeal artery and the retia. Results were evaluated using carotid arteriography, MRI, behavior observation and histology. The unilateral rete mirabile was completely blocked, resulting in disturbance in blood supply to the basal ganglia, astasia of the dght hind limb and salivation. MRI and hematoxylin-eosin staining showed an evident infarction focus in the basal ganglia. These findings indicate that sodium alginate microspheres are a suitable embolic material for blocking the skull base retia in miniature pigs to establish an ischemic stroke models.
基金supported by the National Natural Science Foundation of China (No. 51435012)
文摘Because of the size limitation of weld joints in different regions, the traditional standard bar specimen is not suitable to investigate the mechanical properties of weld joints. In this study, miniature specimens were extracted from specific regions(base metal, weld metal, and three heat-affected zones) of API X80 and X70 weld joints. Uniaxial tensile tests were conducted to obtain the mechanical properties of different regions, and then uniaxial ratcheting tests were conducted to investigate the ratcheting behaviors of the different regions under the same peak and nominal stresses. Under both the tensile tests and ratcheting tests, the weld joints exhibit heterogeneous results, such as different mechanical properties and ratcheting behaviors, which were region dependent. Furthermore, the yield strength and yield-to-tensile strength ratio contribute differently to the ratcheting response.
基金supported by the National Basic Research Program of China (Nos. 2011CBA0100, 2011CB944100, 2011BAI15B02, and se2012BAI39B04)the National High Technology Research and Development Program of China (No. 2012AA020602)+1 种基金the Strategic Priority Research Program of CAS (Nos. XDA08000000 and XDA01030400)the National Natural Science Foundation of China (Nos. 31272440 and 81671274)
文摘Coat color is an important characteristic of various breeds of domestic animal species.Variation in farm animal coat color is of considerable interest for concealment,communication and protection against solar radiation（Slominski et al.,2004）.It also plays an important role in the regulation of physiological processes（Miyagi and Terai,2013）.
基金the China Meteorology Administrationthe China Natural Natural Science Foundation under Grant Nos.49975010,49790020-6.
文摘This article presents a miniature robotic plane meteorological sounding system (RPMSS), which consists of three major subsystems: a miniature robotic plane, an air-borne meteorological sounding and ?ight control system, and a ground-based system. Take-o? and landing of the miniature aircraft are guided by radio control, and the ?ight of the robotic plane along a pre-designed trajectory is automatically piloted by an onboard navigation system. The observed meteorological data as well as all ?ight information are sent back in real time to the ground, then displayed and recorded by the ground-based computer. The ground-based subsystem can also transmit instructions to the air-borne control subsystem. Good system performance has been demonstrated by more than 300 hours of ?ight for atmospheric sounding.
