FY-4A卫星闪电资料与地基ADTD(Advanced Direction and Time of arrival Detecting system)闪电资料对于研究暴雨等强对流天气具有一定的指示意义,通过对四川省冕宁暴雨个例的研究,对比分析了这两种闪电资料的差别,设计了将两种闪电资...FY-4A卫星闪电资料与地基ADTD(Advanced Direction and Time of arrival Detecting system)闪电资料对于研究暴雨等强对流天气具有一定的指示意义,通过对四川省冕宁暴雨个例的研究,对比分析了这两种闪电资料的差别,设计了将两种闪电资料引入数值预报模式的多组数值试验。结果表明:(1)两种闪电资料在不同地区有不同的探测效果,ADTD闪电资料范围更广且分散,FY-4A卫星监测到的闪电数量更密集、分布更集中;两种闪电资料在进入模式之后所转化成的代理雷达回波具有很好的一致性;对于低频次的闪电来说,ADTD闪电定位仪可能比FY-4A闪电成像仪探测效率更高。(2)引入任何一种闪电资料都对降水预报具有正效果,其中ADTD闪电资料的应用对于短时降水预报准确率的提高更为有效。(3)两种闪电资料对于云微物理量的调整作用,在不同的区域有不同效果,说明这两种闪电资料的分布不完全一致,揭示出这两种闪电资料具有一定的互补性。展开更多
Objective This meta-analysis explored whether the expression of actin filament-associated protein 1 antisense RNA 1(AFAP1-AS1)is related to the prognosis and clinicopathological features of patients with cancer.Method...Objective This meta-analysis explored whether the expression of actin filament-associated protein 1 antisense RNA 1(AFAP1-AS1)is related to the prognosis and clinicopathological features of patients with cancer.Methods PubMed,EMBASE,and Cochrane Library were systematically searched.Hazard ratios(HRs)with 95%confidence intervals(CIs)were used to assess the prognostic value based on overall survival(OS),disease-free survival(DFS),and progression-free survival(PFS).Odds ratios(ORs)with 95%CIs were used to determine the relationships between AFAP1-AS1 and clinicopathological features,such as large tumor size(LTS),high tumor stage(HTS),poor histological grade(PHG),lymph node metastasis(LNM),and distant metastasis(DM).Results Thirty-five eligible articles and 3433 cases were analyzed.High AFAP1-AS1 expression,compared to low AFAP1-AS1 expression,correlated with significantly shorter OS(HR=2.15,95%CI=1.97-2.34,P<0.001),DFS(HR=1.37,95%CI=1.19-1.57,P<0.001),and PFS(HR=1.97,95%CI=1.56-2.50,P<0.001)in patients with cancer.In various cancers,elevated AFAP1-AS1 expression was significantly associated with LTS(OR=2.76,95%CI=2.16-3.53,P<0.001),HTS(OR=2.23,95%CI=1.83-2.71,P<0.001),and PHG(OR=1.39,95%CI=1.08-1.79,P=0.01)but not LNM(OR=1.59,95%CI=0.88-2.85,P=0.12)or DM(OR=1.81,95%CI=0.90-3.66,P=0.10).Conclusion High AFAP1-AS1 expression was associated with prognostic and clinicopathological features,suggesting that AFAP1-AS1 is a prognostic biomarker for human cancers.展开更多
Energy crisis promotes the development of renewable energy, especially the solar energy. Sun tracking system proposed in this paper is such a device for efficiency improvement. This closed loop tracking system with tw...Energy crisis promotes the development of renewable energy, especially the solar energy. Sun tracking system proposed in this paper is such a device for efficiency improvement. This closed loop tracking system with two axis sun tracking method is controlled by a programmable logic controller (PLC) and is used for a large dish solar collector. A combination tracking mode combined active and passive tracking methods used in the design make the tracker efficient whatever the circumstances. Two stepper motors and two reduction boxes move the device towards the sun with chain transmission. Besides sun tracking, the system also has functions of overheat monitoring, wind speed monitoring and measurement of illumination.展开更多
Objective: Anemoside B4(AB4), the most abundant triterpenoidal saponin isolated from Pulsatilla chinensis, inhibited influenza virus FM1 or Klebsiella pneumoniae-induced pneumonia. However, the anti-SARS-CoV-2 effect ...Objective: Anemoside B4(AB4), the most abundant triterpenoidal saponin isolated from Pulsatilla chinensis, inhibited influenza virus FM1 or Klebsiella pneumoniae-induced pneumonia. However, the anti-SARS-CoV-2 effect of AB4 has not been unraveled. Therefore, this study aimed to determine the antiviral activity and potential mechanism of AB4 in inhibiting human coronavirus SARS-CoV-2 in vivo and in vitro.Methods: The cytotoxicity of AB4 was evaluated using the Cell Counting Kit-8(CCK8) assay. SARS-CoV-2 infected HEK293T, HPAEpiC, and Vero E6 cells were used for in vitro assays. The antiviral effect of AB4 in vivo was evaluated by SARS-CoV-2-infected hACE2-IRES-luc transgenic mouse model. Furthermore,label-free quantitative proteomics and bioinformatic analysis were performed to explore the potential antiviral mechanism of action of AB4. Type Ⅰ IFN signaling-associated proteins were assessed using Western blotting or immumohistochemical staining.Results: The data showed that AB4 reduced the propagation of SARS-CoV-2 along with the decreased Nucleocapsid protein(N), Spike protein(S), and 3C-like protease(3CLpro) in HEK293T cells. In vivo antiviral activity data revealed that AB4 inhibited viral replication and relieved pneumonia in a SARS-CoV-2 infected mouse model. We further disclosed that the antiviral activity of AB4 was associated with the enhanced interferon(IFN)-β response via the activation of retinoic acid-inducible gene Ⅰ(RIG-1) like receptor(RLP) pathways. Additionally, label-free quantitative proteomic analyses discovered that 17 proteins were significantly altered by AB4 in the SARS-CoV-2 coronavirus infections cells. These proteins mainly clustered in RNA metabolism.Conclusion: Our results indicated that AB4 inhibited SARS-CoV-2 replication through the RLR pathways and moderated the RNA metabolism, suggesting that it would be a potential lead compound for the development of anti-SARS-CoV-2 drugs.展开更多
miR-504 plays a pivotal role in the progression of oral cancer.However,the underlying mechanism remains elusive in vivo.Here,we find that miR-504 is significantly down-regulated in oral cancer patients.We generate miR...miR-504 plays a pivotal role in the progression of oral cancer.However,the underlying mechanism remains elusive in vivo.Here,we find that miR-504 is significantly down-regulated in oral cancer patients.We generate miR-504 knockout mice(miR-504^(-/-))using CRISPR/Cas9 technology to investigate its impact on the malignant progression of oral cancer under exposure to 4-Nitroquinoline N-oxide(4NQO).We show that the deletion of miR-504 does not affect phenotypic characteristics,body weight,reproductive performance,and survival in mice,but results in changes in the blood physiological and biochemical indexes of the mice.Moreover,with 4NQO treatment,miR-504^(-/-)mice exhibit more pronounced pathological changes char-acteristic of oral cancer.RNA sequencing shows that the differentially expressed genes observed in samples from miR-504^(-/-)mice with oral cancer are involved in regulating cell metabolism,cytokine acti-vation,and lipid metabolism-related pathways.Additionally,these differentially expressed genes are significantly enriched in lipid metabolism pathways that influence immune cell infiltration within the tumor microenvironment,thereby accelerating tumor development progression.Collectively,our results suggest that knockout of miR-504 accelerates malignant progression in 4NQO-induced oral cancer by regulating tumor cell proliferation and lipid metabolism,affecting immune cell infiltration.展开更多
Based on the demands of compact heat exchangers and micro cooling channels applied for aviation thermal protection on aero-engines,the elbow localflow resistance charac-teristics for supercritical pressure aviation fu...Based on the demands of compact heat exchangers and micro cooling channels applied for aviation thermal protection on aero-engines,the elbow localflow resistance charac-teristics for supercritical pressure aviation fuel RP-3flowing in adiabatic horizontal serpentine tubes with the inner diameter of 1.8 mm and the massflux of 1179 kg/(m^(2)·s)were experimen-tally studied.The long-short-tube method was used to obtain the elbow pressure drop from the total serpentine tube pressure drop,and the effects of system pressures(P/Pc=1.72-2.58)and geometry parameters including bend numbers(n=5-11),bend diameters(D/d=16.7-27.8),and bend distances(L/d=20-60)on elbow pressure drops and local resistance co-efficients are analyzed on the basis of the thermal physical property variation.The results show that both the increase in the elbow pressure drop and the decrease in the local resistance coef-ficient with temperatures speed up at the near pseudo-critical temperature region of T>0.85Tpc.And the growth of the elbow local pressure drop could be inhibited by the increase of system pressures,while the local resistance coefficient is slightly affected by pressures.The influence of bend diameters on the local resistance coefficient is mild when D/d is larger than 22.2 in the premise of fully developedflow in straight tubes.Furthermore,a piecewise empir-ical correlation considering the bend diameter and physical property ratio is developed to pre-dict the elbow pressure drop of the serpentine tube and optimize the layout of the cooling tube system on aero-engines.展开更多
Wearable sweat sensors are gaining significant attention due to their unparalleled potential for noninvasive health monitoring.Sweat,as a kind of body fluid,contains informative physiological indicators that are relat...Wearable sweat sensors are gaining significant attention due to their unparalleled potential for noninvasive health monitoring.Sweat,as a kind of body fluid,contains informative physiological indicators that are related to personalized health status.Advances in wearable sweat sampling and routing technologies,flexible,and stretchable materials,and wireless digital technologies have led to the development of integrated sweat sensors that are comfortable,flexible,light,and intelligent.Herein,we report a flexible and integrated wearable device via incorporating a microfluidic system and a sensing chip with skin-integrated electronic format toward in-situ monitoring of uric acid(UA)in sweat that associates with gout,cardiovascular,and renal diseases.The microfluidic system validly realizes the real-time capture perspiration from human skin.The obtained detection range is 5-200μM and the detection limit is 1.79μM,which offers an importance diagnostic method for clinical relevant lab test.The soft and flexible features of the constructed device allows it to be mounted onto nearly anywhere on the body.We tested the sweat UA in diverse subjects and various body locations during exercise,and similar trends were also observed by using a commercial UA assay kit.展开更多
Expanding wearable technologies to artificial tactile perception will be of significance for intelligent human-machine interface,as neuromorphic sensing devices are promising candidates due to their low energy consump...Expanding wearable technologies to artificial tactile perception will be of significance for intelligent human-machine interface,as neuromorphic sensing devices are promising candidates due to their low energy consumption and highly effective operating properties.Skin-compatible and conformable features are required for the purpose of realizing wearable artificial tactile perception.Here,we report an intrinsically stretchable,skin-integrated neuromorphic system with triboelectric nanogenerators as tactile sensing and organic electrochemical transistors as information processing.The integrated system provides desired sensing,synaptic,and mechanical characteristics,such as sensitive response(~0.04 kPa^(-1))to low-pressure,short-and long-term synaptic plasticity,great switching endurance(>10000 pulses),symmetric weight update,together with high stretchability of 100%strain.With neural encoding,demonstrations are capable of recognizing,extracting,and encoding features of tactile information.This work provides a feasible approach to wearable,skin-conformable neuromorphic sensing system with great application prospects in intelligent robotics and replacement prosthetics.展开更多
The 2050 carbon-neutral vision spawns a novel energy structure revolution,and the construction of the future energy structure is based on equipment innovation.Insulating material,as the core of electrical power equipm...The 2050 carbon-neutral vision spawns a novel energy structure revolution,and the construction of the future energy structure is based on equipment innovation.Insulating material,as the core of electrical power equipment and electrified transportation asset,faces unprecedented challenges and opportunities.The goal of carbon neutral and the urgent need for innovation in electric power equipment and electrification assets are first discussed.The engineering challenges constrained by the insulation system in future electric power equipment/devices and electrified transportation assets are investigated.Insulating materials,including intelligent insulating material,high thermal conductivity insulating material,high energy storage density insulating material,extreme environment resistant insulating material,and environmental-friendly insulating material,are cat-egorised with their scientific issues,opportunities and challenges under the goal of carbon neutrality being discussed.In the context of carbon neutrality,not only improves the understanding of the insulation problems from a macro level,that is,electrical power equipment and electrified transportation asset,but also offers opportunities,remaining issues and challenges from the insulating material level.It is hoped that this paper en-visions the challenges regarding design and reliability of insulations in electrical equipment and electric vehicles in the context of policies towards carbon neutrality rules.The authors also hope that this paper can be helpful in future development and research of novel insulating materials,which promote the realisation of the carbon-neutral vision.展开更多
The developing secondary flow fields in the entrance section of a rotating straight channel were experimentally investigated using Particle Image Velocimetry(PIV). The effects of streamwise position, Reynolds number...The developing secondary flow fields in the entrance section of a rotating straight channel were experimentally investigated using Particle Image Velocimetry(PIV). The effects of streamwise position, Reynolds number and rotation number on the development of the secondary flow fields were revealed. The results show that the absolute values of vorticity flux of the trailing side roll cells increase with increasing radius of the measured plane and rotation number. When the absolute value of vorticity flux exceeds a critical value, the merging of the trailing side roll cells appears. Moreover, when the number of the trailing side vortex pairs is even, the absolute values of vorticity flux of the leading side vortices increase along streamwise direction. Otherwise, the absolute values decrease along the streamwise direction. By the circulation analysis, this phenomenon was found to have relationship with the merging of the trailing side roll cells, and further concluded that the secondary flow field in a rotating channel has to be treated as a whole. At last,the increase of the Reynolds number was found to be able to induce the merging position moves upstream.展开更多
The buoyancy effect on heat transfer in a rotating,two-pass,square channel is experimentally investigated in curent work.The classical copper plate technique is performed to measure the regional averaged heat transfer...The buoyancy effect on heat transfer in a rotating,two-pass,square channel is experimentally investigated in curent work.The classical copper plate technique is performed to measure the regional averaged heat transfer cofficients.In order to perform a fundamental research,all turbulators are removed away.Two approaches of altering Buoyancy numbers are selected:varying rotation number from 0 to 2.08 at Reynolds number ranges of 10000 to 70000,and varying inlet density ratio from 0.07 to 0.16 at Reynolds number of 10000.And thus,Buoyancy numbers range from 0 to 12.9 for both cases.According to the experimental results,the relationships between heat transfer and Buoyancy numbers are in accord with those obtained under different rotation numbers.For both leading and trailing surface,a critical Buoyancy number exists for each X/D location.Before the critical point,the effect of Buoyancy number on heat transfer is limited;but after that,the Nusselt number ratios show different increase rate.Given the same rotation number,higher wall temperature ratios with its corresponding higher Buoyancy numbers substantially enhance heat transfer on both passages.And the critical exceed-point that heat transfer from trailing surface higher than leading surface happens at the same Buoyancy number for different wall temperature ratios in the second passage.Thus,the stronger buoyancy effect promotes heat transfer enhancement at high rotation number condition.展开更多
The characteristics of flow resistance of a typical hydrocarbon fuel(RP-3)flowthrough adiabatic horizontal miniature tubes at supercritical pressures are experimentallyinvestigated for both laminar and turbulent flow....The characteristics of flow resistance of a typical hydrocarbon fuel(RP-3)flowthrough adiabatic horizontal miniature tubes at supercritical pressures are experimentallyinvestigated for both laminar and turbulent flow.The experiments are conducted by using along tube measuring section and a short tube measuring section simultaneously in order toeliminate the effect of local pressure drop.In these experiments,the temperature of RP-3changes from(295 to 789)K and the reduced pressure(P/Pc,Pc=2.33 MPa)ranges from 1 to2.58,the mass flux is up to 1572.7 kg/(m^(2).s).Test results indicate that frictional pressuredrops for various supercritical pressures at the same mass flux can be considered as equalwith each other when the reduced temperature Tb/Tpc<0.95.When Tb/Tpc>0.95,differenceappears and increases with the increase of Tb/Tpc.Additionally,the friction factor(f)of thesupercritical fluid for turbulent flow has a critical value at Tb/Tpc=1,the values of f at thispoint for all pressures and mass fluxes are equal with each other.Moreover,at the same massflux,there are two comresponding friction factors for the same Re,one is in the region of Tb/Tpc<1,the other is in the region of Tb/Tpc> 1.Finally, classical conelations of frictionfactor is inapplicable when Tb/Tpc>0.95 at supercritical pressure and a new coelation hasbeen obtained based on the experimental data.展开更多
Protein phosphorylation is one of the most important post-translational modifications.It is an active research area to study phosphoproteomics for discovery of disease biomarkers and druggable targets.Here we report t...Protein phosphorylation is one of the most important post-translational modifications.It is an active research area to study phosphoproteomics for discovery of disease biomarkers and druggable targets.Here we report the development of superparamagnetic Fe_(3)O_(4)@mZrO_(2) core-shell microspheres with mesoporous structures for highly efficient enrichment of phosphopeptides.We have demonstrated that the mesoporous ZrO_(2) layer dramatically improves the selective enrichment of phosphopeptides.Our approach allows for in-situ elution and sensitive identification of both mono-phosphorylated and multiphosphorylated peptides in MALDI-TOF mass spectrometry,with the detection limit of down to the femtomole range.The target phosphopeptides can reliably be enriched for MS analysis from various complex samples including the spiked protein digests and tumor cell lysates.The Fe_(3)O_(4)@mZrO_(2) coreshell microspheres promise a useful tool for phosphoproteomics by allowing for highly efficient and selective enrichment of the crucial signaling regulators in a low abundance.展开更多
The wearable lower limb exoskeleton is a typical human-in-loop human–robot coupled system,which conducts natural and close cooperation with the human by recognizing human locomotion timely.Requiring subject-specific ...The wearable lower limb exoskeleton is a typical human-in-loop human–robot coupled system,which conducts natural and close cooperation with the human by recognizing human locomotion timely.Requiring subject-specific training is the main challenge of the existing approaches,and most methods have the problem of insufficient recognition.This paper proposes an integral subject-adaptive real-time Locomotion Mode Recognition(LMR)method based on GA-CNN for a lower limb exoskeleton system.The LMR method is a combination of Convolutional Neural Networks(CNN)and Genetic Algorithm(GA)-based multi-sensor information selection.To improve network performance,the hyper-parameters are optimized by Bayesian optimization.An exoskeleton prototype system with multi-type sensors and novel sensing-shoes is used to verify the proposed method.Twelve locomotion modes,which composed an integral locomotion system for the daily application of the exoskeleton,can be recognized by the proposed method.According to a series of experiments,the recognizer shows strong comprehensive abilities including high accuracy,low delay,and sufficient adaption to different subjects.展开更多
Based on the demands of compact heat exchangers and micro cooling channels applied for aviation thermal protection, the flow resistance characteristics of aviation kerosene RP-3 were experimentally studied in a vertic...Based on the demands of compact heat exchangers and micro cooling channels applied for aviation thermal protection, the flow resistance characteristics of aviation kerosene RP-3 were experimentally studied in a vertically downward circular miniature tube with an inner diameter of 1.86 mm at supercritical pressures and constant heat fluxes. A long and short tube method was used to accurately calculate the frictional pressure drop, and experimental conditions are supercritical pressures of 4 MPa, mass flow rates of 2–4 g/s(i.e., mass fluxes of 736–1472 kg/(m^(2)·s)), heat fluxes of 100–500 kW/m^(2), and inlet temperatures of 373–673 K. Results show that the sharp variations of thermophysical properties, especially density, have significant influences on frictional resistances.Generally, the frictional pressure drop and the friction factor increase with increasing inlet temperatures, and this trend speeds up in the relatively high-temperature region. However, the friction factor has a sudden decline when the fuel outlet temperature exceeds the pseudo-critical temperature.The frictional pressure drop and the friction factor basically remain unchanged with increasing heat flux when the inlet temperature is relatively low, but increase quickly when the inlet temperature is relatively high. Besides, a larger mass flux yields a higher pressure drop but does not necessarily yield a higher friction factor. Finally, an empirical friction factor correlation is proposed and shows better predictive performance than those of previous models.展开更多
This study explores the design,analysis,and air pressure drop assessment of three analogous air–fuel heat exchangers consisting of thin serpentine tube bundles intended for use in high Mach number aero-engines.In hig...This study explores the design,analysis,and air pressure drop assessment of three analogous air–fuel heat exchangers consisting of thin serpentine tube bundles intended for use in high Mach number aero-engines.In high speed flight,the compressor bleed air used to cool high temperature turbine blades and other hot components is too hot.Hence,aviation kerosene is applied to precool the compressor bleed air by means of novel air–fuel heat exchangers.Three light and compact heat exchangers including dozens of in-line thin serpentine tube bundles were designed and manufactured,with little difference existing in aspects of tube pitches and outer diameters among three heat exchangers.The fuel flows inside a series of parallel stainless serpentine tubes(outer diameter:2.2,1.8,1.4 mm with 0.2 mm thickness),while the air externally flows normal to tube bundles and countercurrent with fuel.Experimental studies were carried out to investigate the airside pressure drop characteristics on isothermal states with the variation of air mass flow rates and inlet temperatures.Non-isothermal measurements have also been performed to research the effect of heat transfer on pressure drops.The experimental results show that inlet temperatures have significant influence on pressure drops,and higher temperatures lead to higher pressure drops at the same mass flow rate.The hydraulic resistance coefficient decreases quickly with Reynolds number,and the descent rate slows down when Re>6000 for all three heat exchangers.Additionally,the pressure drop on heat transfer states is less than that on isothermal states for the same average temperatures.Moreover,the pressure drop through heat exchangers is greatly affected by attack angles and transverse pitches,and an asymmetric M-shaped velocity profile is generated in the crosssection of sector channels.展开更多
Unmanned aerial vehicle(UAV)has a rapid development over the last decade.However,an increasing number of severe flight collision events caused by explosive growth of UAV have drawn widespread concern.It is an importan...Unmanned aerial vehicle(UAV)has a rapid development over the last decade.However,an increasing number of severe flight collision events caused by explosive growth of UAV have drawn widespread concern.It is an important issue to investigate safety management approaches of UAVs to ensure safe and efficient operation.In this paper,we present a comprehensive overview of safety management approaches in large,middle and small scales.In large-scale safety management,path-planning problem is a crucial issue to ensure safety and ordered operation of UAVs globally.In middle-scale safety management,it is an important issue to study the conflict detection and resolution methods.And in small-scale safety management,real-time collision avoidance is the last line of ensuring safety.Moreover,a UAV can be regarded as a terminal device connected through communication and information network.Therefore,the enabling technologies,such as sensing,command and control communication,and collaborative decision-making control technology,have been studied in the last.展开更多
文摘FY-4A卫星闪电资料与地基ADTD(Advanced Direction and Time of arrival Detecting system)闪电资料对于研究暴雨等强对流天气具有一定的指示意义,通过对四川省冕宁暴雨个例的研究,对比分析了这两种闪电资料的差别,设计了将两种闪电资料引入数值预报模式的多组数值试验。结果表明:(1)两种闪电资料在不同地区有不同的探测效果,ADTD闪电资料范围更广且分散,FY-4A卫星监测到的闪电数量更密集、分布更集中;两种闪电资料在进入模式之后所转化成的代理雷达回波具有很好的一致性;对于低频次的闪电来说,ADTD闪电定位仪可能比FY-4A闪电成像仪探测效率更高。(2)引入任何一种闪电资料都对降水预报具有正效果,其中ADTD闪电资料的应用对于短时降水预报准确率的提高更为有效。(3)两种闪电资料对于云微物理量的调整作用,在不同的区域有不同效果,说明这两种闪电资料的分布不完全一致,揭示出这两种闪电资料具有一定的互补性。
基金Supported by a grant from the“Ten Thousand Plan”Youth Talent Project in Yunnan Province(no grant number is applicable).
文摘Objective This meta-analysis explored whether the expression of actin filament-associated protein 1 antisense RNA 1(AFAP1-AS1)is related to the prognosis and clinicopathological features of patients with cancer.Methods PubMed,EMBASE,and Cochrane Library were systematically searched.Hazard ratios(HRs)with 95%confidence intervals(CIs)were used to assess the prognostic value based on overall survival(OS),disease-free survival(DFS),and progression-free survival(PFS).Odds ratios(ORs)with 95%CIs were used to determine the relationships between AFAP1-AS1 and clinicopathological features,such as large tumor size(LTS),high tumor stage(HTS),poor histological grade(PHG),lymph node metastasis(LNM),and distant metastasis(DM).Results Thirty-five eligible articles and 3433 cases were analyzed.High AFAP1-AS1 expression,compared to low AFAP1-AS1 expression,correlated with significantly shorter OS(HR=2.15,95%CI=1.97-2.34,P<0.001),DFS(HR=1.37,95%CI=1.19-1.57,P<0.001),and PFS(HR=1.97,95%CI=1.56-2.50,P<0.001)in patients with cancer.In various cancers,elevated AFAP1-AS1 expression was significantly associated with LTS(OR=2.76,95%CI=2.16-3.53,P<0.001),HTS(OR=2.23,95%CI=1.83-2.71,P<0.001),and PHG(OR=1.39,95%CI=1.08-1.79,P=0.01)but not LNM(OR=1.59,95%CI=0.88-2.85,P=0.12)or DM(OR=1.81,95%CI=0.90-3.66,P=0.10).Conclusion High AFAP1-AS1 expression was associated with prognostic and clinicopathological features,suggesting that AFAP1-AS1 is a prognostic biomarker for human cancers.
文摘Energy crisis promotes the development of renewable energy, especially the solar energy. Sun tracking system proposed in this paper is such a device for efficiency improvement. This closed loop tracking system with two axis sun tracking method is controlled by a programmable logic controller (PLC) and is used for a large dish solar collector. A combination tracking mode combined active and passive tracking methods used in the design make the tracker efficient whatever the circumstances. Two stepper motors and two reduction boxes move the device towards the sun with chain transmission. Besides sun tracking, the system also has functions of overheat monitoring, wind speed monitoring and measurement of illumination.
基金supported by National Natural Science Foundation of China(No.82341087,82073912)Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions.
文摘Objective: Anemoside B4(AB4), the most abundant triterpenoidal saponin isolated from Pulsatilla chinensis, inhibited influenza virus FM1 or Klebsiella pneumoniae-induced pneumonia. However, the anti-SARS-CoV-2 effect of AB4 has not been unraveled. Therefore, this study aimed to determine the antiviral activity and potential mechanism of AB4 in inhibiting human coronavirus SARS-CoV-2 in vivo and in vitro.Methods: The cytotoxicity of AB4 was evaluated using the Cell Counting Kit-8(CCK8) assay. SARS-CoV-2 infected HEK293T, HPAEpiC, and Vero E6 cells were used for in vitro assays. The antiviral effect of AB4 in vivo was evaluated by SARS-CoV-2-infected hACE2-IRES-luc transgenic mouse model. Furthermore,label-free quantitative proteomics and bioinformatic analysis were performed to explore the potential antiviral mechanism of action of AB4. Type Ⅰ IFN signaling-associated proteins were assessed using Western blotting or immumohistochemical staining.Results: The data showed that AB4 reduced the propagation of SARS-CoV-2 along with the decreased Nucleocapsid protein(N), Spike protein(S), and 3C-like protease(3CLpro) in HEK293T cells. In vivo antiviral activity data revealed that AB4 inhibited viral replication and relieved pneumonia in a SARS-CoV-2 infected mouse model. We further disclosed that the antiviral activity of AB4 was associated with the enhanced interferon(IFN)-β response via the activation of retinoic acid-inducible gene Ⅰ(RIG-1) like receptor(RLP) pathways. Additionally, label-free quantitative proteomic analyses discovered that 17 proteins were significantly altered by AB4 in the SARS-CoV-2 coronavirus infections cells. These proteins mainly clustered in RNA metabolism.Conclusion: Our results indicated that AB4 inhibited SARS-CoV-2 replication through the RLR pathways and moderated the RNA metabolism, suggesting that it would be a potential lead compound for the development of anti-SARS-CoV-2 drugs.
基金This work was supported by the National Natural Science Foundation of China(31970513 to G.S.)the Central Government's Guide to Local Science and Technology Development Fund(YDZJSX2022A060 to G.S.)+2 种基金the special funds for Science and Technology Innovation Teams of Shanxi Province(202204051002032 to G.S.)the Shanxi Province Higher Education"BillionProject"Science and Technology Guidance Project(BYJLO16 to G.S.)the Natural Science Foundation of Shanxi Province(20210302124093 to J.G.).
文摘miR-504 plays a pivotal role in the progression of oral cancer.However,the underlying mechanism remains elusive in vivo.Here,we find that miR-504 is significantly down-regulated in oral cancer patients.We generate miR-504 knockout mice(miR-504^(-/-))using CRISPR/Cas9 technology to investigate its impact on the malignant progression of oral cancer under exposure to 4-Nitroquinoline N-oxide(4NQO).We show that the deletion of miR-504 does not affect phenotypic characteristics,body weight,reproductive performance,and survival in mice,but results in changes in the blood physiological and biochemical indexes of the mice.Moreover,with 4NQO treatment,miR-504^(-/-)mice exhibit more pronounced pathological changes char-acteristic of oral cancer.RNA sequencing shows that the differentially expressed genes observed in samples from miR-504^(-/-)mice with oral cancer are involved in regulating cell metabolism,cytokine acti-vation,and lipid metabolism-related pathways.Additionally,these differentially expressed genes are significantly enriched in lipid metabolism pathways that influence immune cell infiltration within the tumor microenvironment,thereby accelerating tumor development progression.Collectively,our results suggest that knockout of miR-504 accelerates malignant progression in 4NQO-induced oral cancer by regulating tumor cell proliferation and lipid metabolism,affecting immune cell infiltration.
基金Fundamental Research Funds for the Central Universities (No.501XTCX2023146001 and 501QYZX2023146001)the National Major Science and Technology Projects of China (Nos.J2019-III-0021-0065 and J2019-III-0015-0059)the Science Center for Gas Turbine Project (No.P2022-C-II-005-001).
文摘Based on the demands of compact heat exchangers and micro cooling channels applied for aviation thermal protection on aero-engines,the elbow localflow resistance charac-teristics for supercritical pressure aviation fuel RP-3flowing in adiabatic horizontal serpentine tubes with the inner diameter of 1.8 mm and the massflux of 1179 kg/(m^(2)·s)were experimen-tally studied.The long-short-tube method was used to obtain the elbow pressure drop from the total serpentine tube pressure drop,and the effects of system pressures(P/Pc=1.72-2.58)and geometry parameters including bend numbers(n=5-11),bend diameters(D/d=16.7-27.8),and bend distances(L/d=20-60)on elbow pressure drops and local resistance co-efficients are analyzed on the basis of the thermal physical property variation.The results show that both the increase in the elbow pressure drop and the decrease in the local resistance coef-ficient with temperatures speed up at the near pseudo-critical temperature region of T>0.85Tpc.And the growth of the elbow local pressure drop could be inhibited by the increase of system pressures,while the local resistance coefficient is slightly affected by pressures.The influence of bend diameters on the local resistance coefficient is mild when D/d is larger than 22.2 in the premise of fully developedflow in straight tubes.Furthermore,a piecewise empir-ical correlation considering the bend diameter and physical property ratio is developed to pre-dict the elbow pressure drop of the serpentine tube and optimize the layout of the cooling tube system on aero-engines.
基金This work was also sponsored by InnoHK Project on Project 2.2-artificial intelligent(Al)-based 3D ultrasound imaging algorithm at Hong Kong Centre for Cerebro-Cardiovascular Health Engineering(CoCHE),Center of Flexible Electronics Technology,and Qiantang Science and Technology Innovation Center.
文摘Wearable sweat sensors are gaining significant attention due to their unparalleled potential for noninvasive health monitoring.Sweat,as a kind of body fluid,contains informative physiological indicators that are related to personalized health status.Advances in wearable sweat sampling and routing technologies,flexible,and stretchable materials,and wireless digital technologies have led to the development of integrated sweat sensors that are comfortable,flexible,light,and intelligent.Herein,we report a flexible and integrated wearable device via incorporating a microfluidic system and a sensing chip with skin-integrated electronic format toward in-situ monitoring of uric acid(UA)in sweat that associates with gout,cardiovascular,and renal diseases.The microfluidic system validly realizes the real-time capture perspiration from human skin.The obtained detection range is 5-200μM and the detection limit is 1.79μM,which offers an importance diagnostic method for clinical relevant lab test.The soft and flexible features of the constructed device allows it to be mounted onto nearly anywhere on the body.We tested the sweat UA in diverse subjects and various body locations during exercise,and similar trends were also observed by using a commercial UA assay kit.
基金The Foundation of National Natural Science Foundation of China,Grant/Award Number:61421002City University of Hong Kong,Grant/Award Numbers:9678274,9667221,9680322+5 种基金Research Grants Council of Hong Kong Special Administrative Region,Grant/Award Numbers:21210820,11213721,11215722Regional Joint Fund of the National Science Foundation of China,Grant/Award Number:U21A20492The Sichuan Science and Technology Program,Grant/Award Numbers:2022YFH0081,2022YFG0012,2022YFG0013The Sichuan Province Key Laboratory of Display Science and TechnologyInnoHK Project on Project 2.2—AI-based 3D ultrasound imaging algorithm at Hong Kong Centre for Cerebro-Cardiovascular Health Engineering(COCHE)RGC Senior Research Fellow Scheme,Grant/Award Number:SRFS2122-5S04.
文摘Expanding wearable technologies to artificial tactile perception will be of significance for intelligent human-machine interface,as neuromorphic sensing devices are promising candidates due to their low energy consumption and highly effective operating properties.Skin-compatible and conformable features are required for the purpose of realizing wearable artificial tactile perception.Here,we report an intrinsically stretchable,skin-integrated neuromorphic system with triboelectric nanogenerators as tactile sensing and organic electrochemical transistors as information processing.The integrated system provides desired sensing,synaptic,and mechanical characteristics,such as sensitive response(~0.04 kPa^(-1))to low-pressure,short-and long-term synaptic plasticity,great switching endurance(>10000 pulses),symmetric weight update,together with high stretchability of 100%strain.With neural encoding,demonstrations are capable of recognizing,extracting,and encoding features of tactile information.This work provides a feasible approach to wearable,skin-conformable neuromorphic sensing system with great application prospects in intelligent robotics and replacement prosthetics.
文摘The 2050 carbon-neutral vision spawns a novel energy structure revolution,and the construction of the future energy structure is based on equipment innovation.Insulating material,as the core of electrical power equipment and electrified transportation asset,faces unprecedented challenges and opportunities.The goal of carbon neutral and the urgent need for innovation in electric power equipment and electrification assets are first discussed.The engineering challenges constrained by the insulation system in future electric power equipment/devices and electrified transportation assets are investigated.Insulating materials,including intelligent insulating material,high thermal conductivity insulating material,high energy storage density insulating material,extreme environment resistant insulating material,and environmental-friendly insulating material,are cat-egorised with their scientific issues,opportunities and challenges under the goal of carbon neutrality being discussed.In the context of carbon neutrality,not only improves the understanding of the insulation problems from a macro level,that is,electrical power equipment and electrified transportation asset,but also offers opportunities,remaining issues and challenges from the insulating material level.It is hoped that this paper en-visions the challenges regarding design and reliability of insulations in electrical equipment and electric vehicles in the context of policies towards carbon neutrality rules.The authors also hope that this paper can be helpful in future development and research of novel insulating materials,which promote the realisation of the carbon-neutral vision.
基金financially supported by the Academic Excellence Foundation of BUAA for Ph.D.studentsthe National Natural Science Foundation of China (No. 51506002)
文摘The developing secondary flow fields in the entrance section of a rotating straight channel were experimentally investigated using Particle Image Velocimetry(PIV). The effects of streamwise position, Reynolds number and rotation number on the development of the secondary flow fields were revealed. The results show that the absolute values of vorticity flux of the trailing side roll cells increase with increasing radius of the measured plane and rotation number. When the absolute value of vorticity flux exceeds a critical value, the merging of the trailing side roll cells appears. Moreover, when the number of the trailing side vortex pairs is even, the absolute values of vorticity flux of the leading side vortices increase along streamwise direction. Otherwise, the absolute values decrease along the streamwise direction. By the circulation analysis, this phenomenon was found to have relationship with the merging of the trailing side roll cells, and further concluded that the secondary flow field in a rotating channel has to be treated as a whole. At last,the increase of the Reynolds number was found to be able to induce the merging position moves upstream.
文摘The buoyancy effect on heat transfer in a rotating,two-pass,square channel is experimentally investigated in curent work.The classical copper plate technique is performed to measure the regional averaged heat transfer cofficients.In order to perform a fundamental research,all turbulators are removed away.Two approaches of altering Buoyancy numbers are selected:varying rotation number from 0 to 2.08 at Reynolds number ranges of 10000 to 70000,and varying inlet density ratio from 0.07 to 0.16 at Reynolds number of 10000.And thus,Buoyancy numbers range from 0 to 12.9 for both cases.According to the experimental results,the relationships between heat transfer and Buoyancy numbers are in accord with those obtained under different rotation numbers.For both leading and trailing surface,a critical Buoyancy number exists for each X/D location.Before the critical point,the effect of Buoyancy number on heat transfer is limited;but after that,the Nusselt number ratios show different increase rate.Given the same rotation number,higher wall temperature ratios with its corresponding higher Buoyancy numbers substantially enhance heat transfer on both passages.And the critical exceed-point that heat transfer from trailing surface higher than leading surface happens at the same Buoyancy number for different wall temperature ratios in the second passage.Thus,the stronger buoyancy effect promotes heat transfer enhancement at high rotation number condition.
基金the Natural Science Foundation of China under Contract No.50676005.
文摘The characteristics of flow resistance of a typical hydrocarbon fuel(RP-3)flowthrough adiabatic horizontal miniature tubes at supercritical pressures are experimentallyinvestigated for both laminar and turbulent flow.The experiments are conducted by using along tube measuring section and a short tube measuring section simultaneously in order toeliminate the effect of local pressure drop.In these experiments,the temperature of RP-3changes from(295 to 789)K and the reduced pressure(P/Pc,Pc=2.33 MPa)ranges from 1 to2.58,the mass flux is up to 1572.7 kg/(m^(2).s).Test results indicate that frictional pressuredrops for various supercritical pressures at the same mass flux can be considered as equalwith each other when the reduced temperature Tb/Tpc<0.95.When Tb/Tpc>0.95,differenceappears and increases with the increase of Tb/Tpc.Additionally,the friction factor(f)of thesupercritical fluid for turbulent flow has a critical value at Tb/Tpc=1,the values of f at thispoint for all pressures and mass fluxes are equal with each other.Moreover,at the same massflux,there are two comresponding friction factors for the same Re,one is in the region of Tb/Tpc<1,the other is in the region of Tb/Tpc> 1.Finally, classical conelations of frictionfactor is inapplicable when Tb/Tpc>0.95 at supercritical pressure and a new coelation hasbeen obtained based on the experimental data.
基金supported by the National Key Research and Development Program of China(2017YFE0131700)and the National Natural Science Foundation of China(21874096)+3 种基金a project supported by Collaborative Innovation Center of Suzhou Nano Science and Technologythe 111 ProjectJoint International Research Laboratory of Carbon-Based Functional Materials and Devicesthe Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Protein phosphorylation is one of the most important post-translational modifications.It is an active research area to study phosphoproteomics for discovery of disease biomarkers and druggable targets.Here we report the development of superparamagnetic Fe_(3)O_(4)@mZrO_(2) core-shell microspheres with mesoporous structures for highly efficient enrichment of phosphopeptides.We have demonstrated that the mesoporous ZrO_(2) layer dramatically improves the selective enrichment of phosphopeptides.Our approach allows for in-situ elution and sensitive identification of both mono-phosphorylated and multiphosphorylated peptides in MALDI-TOF mass spectrometry,with the detection limit of down to the femtomole range.The target phosphopeptides can reliably be enriched for MS analysis from various complex samples including the spiked protein digests and tumor cell lysates.The Fe_(3)O_(4)@mZrO_(2) coreshell microspheres promise a useful tool for phosphoproteomics by allowing for highly efficient and selective enrichment of the crucial signaling regulators in a low abundance.
文摘The wearable lower limb exoskeleton is a typical human-in-loop human–robot coupled system,which conducts natural and close cooperation with the human by recognizing human locomotion timely.Requiring subject-specific training is the main challenge of the existing approaches,and most methods have the problem of insufficient recognition.This paper proposes an integral subject-adaptive real-time Locomotion Mode Recognition(LMR)method based on GA-CNN for a lower limb exoskeleton system.The LMR method is a combination of Convolutional Neural Networks(CNN)and Genetic Algorithm(GA)-based multi-sensor information selection.To improve network performance,the hyper-parameters are optimized by Bayesian optimization.An exoskeleton prototype system with multi-type sensors and novel sensing-shoes is used to verify the proposed method.Twelve locomotion modes,which composed an integral locomotion system for the daily application of the exoskeleton,can be recognized by the proposed method.According to a series of experiments,the recognizer shows strong comprehensive abilities including high accuracy,low delay,and sufficient adaption to different subjects.
基金co-supported by the National Science and Technology Major Project of China(Nos.2017-Ⅲ-00050029,J2019-Ⅲ-0021-0065,and J2019-Ⅲ-0015-0059)the National Natural Science Foundation of China(No.51906009)。
文摘Based on the demands of compact heat exchangers and micro cooling channels applied for aviation thermal protection, the flow resistance characteristics of aviation kerosene RP-3 were experimentally studied in a vertically downward circular miniature tube with an inner diameter of 1.86 mm at supercritical pressures and constant heat fluxes. A long and short tube method was used to accurately calculate the frictional pressure drop, and experimental conditions are supercritical pressures of 4 MPa, mass flow rates of 2–4 g/s(i.e., mass fluxes of 736–1472 kg/(m^(2)·s)), heat fluxes of 100–500 kW/m^(2), and inlet temperatures of 373–673 K. Results show that the sharp variations of thermophysical properties, especially density, have significant influences on frictional resistances.Generally, the frictional pressure drop and the friction factor increase with increasing inlet temperatures, and this trend speeds up in the relatively high-temperature region. However, the friction factor has a sudden decline when the fuel outlet temperature exceeds the pseudo-critical temperature.The frictional pressure drop and the friction factor basically remain unchanged with increasing heat flux when the inlet temperature is relatively low, but increase quickly when the inlet temperature is relatively high. Besides, a larger mass flux yields a higher pressure drop but does not necessarily yield a higher friction factor. Finally, an empirical friction factor correlation is proposed and shows better predictive performance than those of previous models.
基金co-supported by the National Science and Technology Major Project of China (Nos. 2017-Ⅲ-00050029, J2019-Ⅲ-0021-0065, and J2019-Ⅲ-0015-0059)the National Natural Science Foundation of China (No. 51906009)
文摘This study explores the design,analysis,and air pressure drop assessment of three analogous air–fuel heat exchangers consisting of thin serpentine tube bundles intended for use in high Mach number aero-engines.In high speed flight,the compressor bleed air used to cool high temperature turbine blades and other hot components is too hot.Hence,aviation kerosene is applied to precool the compressor bleed air by means of novel air–fuel heat exchangers.Three light and compact heat exchangers including dozens of in-line thin serpentine tube bundles were designed and manufactured,with little difference existing in aspects of tube pitches and outer diameters among three heat exchangers.The fuel flows inside a series of parallel stainless serpentine tubes(outer diameter:2.2,1.8,1.4 mm with 0.2 mm thickness),while the air externally flows normal to tube bundles and countercurrent with fuel.Experimental studies were carried out to investigate the airside pressure drop characteristics on isothermal states with the variation of air mass flow rates and inlet temperatures.Non-isothermal measurements have also been performed to research the effect of heat transfer on pressure drops.The experimental results show that inlet temperatures have significant influence on pressure drops,and higher temperatures lead to higher pressure drops at the same mass flow rate.The hydraulic resistance coefficient decreases quickly with Reynolds number,and the descent rate slows down when Re>6000 for all three heat exchangers.Additionally,the pressure drop on heat transfer states is less than that on isothermal states for the same average temperatures.Moreover,the pressure drop through heat exchangers is greatly affected by attack angles and transverse pitches,and an asymmetric M-shaped velocity profile is generated in the crosssection of sector channels.
基金This work was supported by the National Key Laboratory of CNS/ATM,Bei-jing Key Laboratory for Network-based Cooperative Air Traffic Manage-ment and the State Key Program of National Natural Science of China(No.71731001)。
文摘Unmanned aerial vehicle(UAV)has a rapid development over the last decade.However,an increasing number of severe flight collision events caused by explosive growth of UAV have drawn widespread concern.It is an important issue to investigate safety management approaches of UAVs to ensure safe and efficient operation.In this paper,we present a comprehensive overview of safety management approaches in large,middle and small scales.In large-scale safety management,path-planning problem is a crucial issue to ensure safety and ordered operation of UAVs globally.In middle-scale safety management,it is an important issue to study the conflict detection and resolution methods.And in small-scale safety management,real-time collision avoidance is the last line of ensuring safety.Moreover,a UAV can be regarded as a terminal device connected through communication and information network.Therefore,the enabling technologies,such as sensing,command and control communication,and collaborative decision-making control technology,have been studied in the last.