Unmanned Aerial Vehicles(UAVs)enabled Aerial Base Stations(UABSs)have been studied widely in future communications.However,there are a series of challenges such as interference management,trajectory design and resourc...Unmanned Aerial Vehicles(UAVs)enabled Aerial Base Stations(UABSs)have been studied widely in future communications.However,there are a series of challenges such as interference management,trajectory design and resource allocation in the scenarios of multi-UAV networks.Besides,different performances among UABSs increase complexity and bring many challenges.In this paper,the joint downlink transmission power control and trajectory design problem in multi-type UABSs communication network is investigated.In order to satisfy the signal to interference plus noise power ratio of users,each UABS needs to adjust its position and transmission power.Based on the interactions among multiple communication links,a non-cooperative Mean-Field-Type Game(MFTG)is proposed to model the joint optimization problem.Then,a Nash equilibrium solution is solved by two steps:first,the users in the given area are clustered to get the initial deployment of the UABSs;second,the Mean-Field Q(MFQ)-learning algorithm is proposed to solve the discrete MFTG problem.Finally,the effectiveness of the approach is verified through the simulations,which simplifies the solution process and effectively reduces the energy consumption of each UABS.展开更多
Reconfigurable intelligent surface(RIS)has been proposed as a potential solution to improve the coverage and spectrum efficiency for future wireless communication.However,the privacy of users’data is often ignored in...Reconfigurable intelligent surface(RIS)has been proposed as a potential solution to improve the coverage and spectrum efficiency for future wireless communication.However,the privacy of users’data is often ignored in previous works,such as the user’s location information during channel estimation.In this paper,we propose a privacy-preserving design paradigm combining federated learning(FL)with RIS in the mmWave communication system.Based on FL,the local models are trained and encrypted using the private data managed on each local device.Following this,a global model is generated by aggregating them at the central server.The optimal model is trained for establishing the mapping function between channel state information(CSI)and RIS’configuration matrix in order to maximize the achievable rate of the received signal.Simulation results demonstrate that the proposed scheme can effectively approach to the theoretical value generated by centralized machine learning(ML),while protecting user’privacy.展开更多
Recent studies regarding neuronal differentiation of mesenchymal stem cells （MSCs） have primarily focused on induction methods and transplantation in vivo. However, knowledge about the intrinsic regulatory mechanism...Recent studies regarding neuronal differentiation of mesenchymal stem cells （MSCs） have primarily focused on induction methods and transplantation in vivo. However, knowledge about the intrinsic regulatory mechanisms underlying neuronal induction of MSCs remains limited and unclear. OBJECTIVE： To elucidate the role of JAK-STAT3 signaling pathway during neuronal differentiation of MSCs using a combination of the JAK-STAT3 signaling inhibitor AG490 and growth factors. DESIGN, TIME AND SETTING： Neural, molecular, biomedical, in vitro experiment was performed at the Laboratory of Pharmacology, School of Pharmacy, Nanjing Medical University between March and December 2008 MATERIALS： An inhibitor of the JAK-STAT3 signaling pathway was purchased from Calbiochem, USA. Antibody kit for total and phosphorylated STAT3 was purchased from Cell Signaling, USA. METHODS： MSCs from passage 3 were assigned to non-induced, growth factor, and AG490 groups. MAIN OUTCOME MEASURE： The number of cells expressing neuron-specific enolase, microtubule-associated protein, and glial fibrillary acidic protein were determined by immunocytochemistry. Total and phosphorylated （Tyr705） expression levels of STAT3 protein were measured by Western blot analysis. RESULTS： MSCs were transdifferentiated into neuronal- and astrocyte-like phenotypes through the induction of epidermal growth factor, basic fibroblast growth factor, and brain-derived neurotrophic factor. In addition, the JAK-STAT3 signaling pathway was significantly activated during neural differentiation. Expression of phosphorylated （Tyr705） STAT3 was inhibited with AG490 （5 pmol/L） prior to neural induction with epidermal growth factor, basic fibroblast growth factor, and brain-derived neurotrophic factor; proportion of astrocyte-like cells was significantly reduced （P 〈 0.01）, and the proportion of neuronal-like phenotypes was significantly increased （P〈 0.01）. CONCLUSION： JAK-STAT3 signaling pathway was shown to regulate neuronal induction of bone marrow MSCs. The proportion of MSC-induced neuronal-like cells was increased following treatment with the JAK-STAT3 signaling inhibitor AG490.展开更多
Information freshness is a key factor for Internet-of-Things(IoT)to make appropriate decisions and operations.This paper proposes an analytical framework for evaluating the timeliness performance of the IoT system bas...Information freshness is a key factor for Internet-of-Things(IoT)to make appropriate decisions and operations.This paper proposes an analytical framework for evaluating the timeliness performance of the IoT system based on Unmanned Aerial Vehicle(UAV)lossy communications.The performance analysis consists of the outage probability analysis and the Age-of-Information(AoI)analysis with outages.To begin with,we solve a lossy coding problem formulated from the UAV communication system,and derive a closed-form expression of the outage probability based on Shannon's lossy source-channel separation theorem.Then,we characterize the Peak AoI(PAoI)for the considered system,and further minimize the PAoI by deriving the optimal rate for generating information.Moreover,we analyze the system performance through theoretical calculations and simulations.The results indicate that the optimal server utilization ratio is always no larger than 0.5.In practical applications,we can utilize the proposed analytical framework to determine the system parameters which guarantee the timeliness performance of UAV lossy communications.展开更多
Weak interactions prevent the magnetic particles from achieving excellent electromagnetic wave absorp-tion(EMA)at a low filler loading(FL).The construction of one-dimensional magnetic metal fibers(1D-MMFs)contributes ...Weak interactions prevent the magnetic particles from achieving excellent electromagnetic wave absorp-tion(EMA)at a low filler loading(FL).The construction of one-dimensional magnetic metal fibers(1D-MMFs)contributes to the formation of an electromagnetic(EM)coupling network,enhancing EM properties at a low FL.However,precisely controlling the length of 1D-MMFs to regulate permittivity at low FL poses a challenge.Herein,a novel magnetic field-assisted growth strategy was used to fabricate Co-based fibers with adjustable permittivity and aspect ratios.With a variety of FL changes,centimeter-level Co long fibers(Co-lf)consistently exhibited higher permittivity than Co particles and Co short fibers due to the enhancement of the effective EM coupling.The Co-lf exhibits excellent EMA performance(-54.85 dB,5.8 GHz)at 10 wt.%FL.Meanwhile,heterogeneous interfaces were introduced to increase the interfacial polarization through a fine phosphorylation design,resulting in elevated EMA performances(-51.50 dB,6.6 GHz)at 10 wt.%FL for Co_(2)P/Co long fibers.This study improves the orderliness of the particle arrangement by regulating the length of 1D-MMFs,which affects the behavior of electrons inside the fibers,providing a new perspective for improving the EMA properties of magnetic materials at a low FL.展开更多
To promote the achievement of high-quality and full employment goals for students in higher education,this paper analyzes the integration path of practical education and teaching in civil engineering and transportatio...To promote the achievement of high-quality and full employment goals for students in higher education,this paper analyzes the integration path of practical education and teaching in civil engineering and transportation majors,guided by surveying employment.This paper proposes three integration paths for practical teaching and education in civil engineering and transportation majors under the employment orientation.The first path is to create a modularized and informatized curriculum system.The second path is to deepen diverse cooperative practices between schools and enterprises.The third path is to construct a diversified quality evaluation system for academic achievement.To ensure the quality of education and employment,schools should continuously evaluate and reflect on the practical effects of these three paths to further optimize them.展开更多
The genes for 5-1ipoxygenase activating protein （ALOX5AP） and phosphodiesterase 4D （PDE4D） have been demonstrated as susceptibility genes for lacunar in the Icelandic and Pakistani populations, but little is known...The genes for 5-1ipoxygenase activating protein （ALOX5AP） and phosphodiesterase 4D （PDE4D） have been demonstrated as susceptibility genes for lacunar in the Icelandic and Pakistani populations, but little is known about the role of these genes in Chinese populations. The present study utilized polymerase chain reaction and ligase detection reaction to detect single nucleotide polymorphisms （SNPs） in 280 consecutive stroke patients and 258 unrelated population-based controls from Nanjing, Jiangsu Province, China. The allele frequency, genotypes, and haplotypes of the two SNPs （rs456009 and rs966221） in PDE4D were similar between the two groups. However, A allele frequency of rs4073259 （A/G） and rs4769055 （A/C） in the ALOX5AP gene exhibited differences in two groups, and especially the haplotype of the SNP was significantly different between the two groups. Results suggested that the ALOX5AP gene might be involved in lacunar infarct, while PDE4D gene was not a risk factor for lacunar infarct in individuals from Jiangsu Province, China.展开更多
In order to improve the energy efficiency(EE)in the underlay cognitive radio(CR)networks,a power allocation strategy based on an actor-critic reinforcement learning is proposed,where a cluster of cognitive users(CUs)c...In order to improve the energy efficiency(EE)in the underlay cognitive radio(CR)networks,a power allocation strategy based on an actor-critic reinforcement learning is proposed,where a cluster of cognitive users(CUs)can simultaneously access to the same primary spectrum band under the interference constraints of the primary user(PU),by employing the non-orthogonal multiple access(NOMA)technique.In the proposed scheme,the optimization of the power allocation is formulated as a non-convex optimization problem.Additionally,the power allocation for different CUs is based on the actor-critic reinforcement learning model,in which the weighted data rate is set as the reward function,and the generated action strategy(i.e.the power allocation)is iteratively criticized and updated.Both the CU’s spectral efficiency and the PU’s interference constrains are considered in the training of the actor-critic reinforcement learning.Furthermore,the first order Taylor approximation as well as other manipulations are adopted to solve the power allocation optimization problem for the sake of considering the conventional channel conditions.According to the simulation results,we find that our scheme could achieve a higher spectral efficiency for the CUs compared to a benchmark scheme without learning process as well as the existing Q-learning based method,while the resultant interference affecting the PU transmission can be maintained at a given tolerated limit.展开更多
In order to improve the physical layer security of the device-to-device(D2D)cellular network,we propose a collaborative scheme for the transmit antenna selection and the optimal D2D pair establishment based on deep le...In order to improve the physical layer security of the device-to-device(D2D)cellular network,we propose a collaborative scheme for the transmit antenna selection and the optimal D2D pair establishment based on deep learning.Due to the mobility of users,using the current channel state information to select a transmit antenna or establish a D2D pair for the next time slot cannot ensure secure communication.Therefore,in this paper,we utilize the Echo State Network(ESN)to select the transmit antenna and the Long Short-Term Memory(LSTM)to establish the D2D pair.The simulation results show that the LSTMbased and ESN-based collaboration scheme can effectively improve the security capacity of the cellular network with D2D and increase the life of the base station.展开更多
In order to evaluate the influence of microbial community structure of seed sludge on the properties of aerobic nitrifying granules, these granules were cultivated with different seed sludge, and the variation of micr...In order to evaluate the influence of microbial community structure of seed sludge on the properties of aerobic nitrifying granules, these granules were cultivated with different seed sludge, and the variation of microbial community and dominant bacterial groups that impact the nitrogen removal efficiency of the aerobic nitrifying granules were analyzed and identified using 16 s rDNA sequence and denaturing gradient gel electrophoresis（DGGE） profiles. The results presented here demonstrated that the influence of the community structure of seed sludge on the properties of aerobic nitrifying granules was remarkable, and the granules cultivated by activated sludge from a beer wastewater treatment plant showed better performance, with a stable sludge volume index（SVI） value of 20 m L/g, high extracellular polymeric substance（EPS） content of 183.3 mg/L, high NH4＋-N removal rate of 89.42% and abundant microbial population with 10 dominant bacterial groups. This indicated that activated sludge with abundant communities is suitable for use as seed sludge in culturing aerobic nitrifying granules.展开更多
Future Sixth-Generation (6G) mobile communication networks extremely require the global connectivity and the ground Base Stations (BSs) are difficult to develop in some specific areas,such as mountainous areas.Therefo...Future Sixth-Generation (6G) mobile communication networks extremely require the global connectivity and the ground Base Stations (BSs) are difficult to develop in some specific areas,such as mountainous areas.Therefore,the aerial networks are the key framework for the future communications,in which the aerial vehicle could act as the access point.Additionally,Mobile Edge Computing (MEC) is also essential to enhance the data processing capabilities of aerial networks.In this paper,we study a comprehensive communication-computation resource management problem for jointly optimizing user pairing,power and time allocation in the MEC aided Cognitive Radio (CR) aerial networks,namely CR-MEC aerial networks.Explicitly,this multilevel optimization problem could be decomposed into the user pairing and power allocation as well as time allocation sub-problems.In the conceived CR-MEC aerial networks,we propose a User Pairing and Computation Offloading Management Algorithm (UPCOMA) based on three-sided matching theory,aiming to minimize the system’s energy consumption.At the first step of UPCOMA,multiple Primary Users (PUs) and Cognitive Users (CUs) on the ground negotiate to each other with the suitable power allocation coefficients and construct the stable user pairs.Moreover,the stable user pairs would match to a high altitude platform who act as the base station,which is for appropriately allocating Transmission Time Slots (TSs) at the second step of UPCOMA.Additionally,a hybrid offloading mode is proposed in our conceived networks in order to support ground users to offload their tasks adaptively according to their individual deadlines.Furthermore,the simulation results reveal that the relative performance of UPCOMA is close to that of the Brute-Force Search Algorithm (BFSA) with low complexity.Meanwhile,the hybrid offloading mode with less energy consumption supports much more ground user pairs to offload tasks compared to the binary mode.展开更多
A compound bioflocculant CBF,produced by mixed culture of Rhizobium radiobacter F2 and Bacillus sphaeicus F6, was investigated with regard to its production and flocculating properties. The optimization of the culture...A compound bioflocculant CBF,produced by mixed culture of Rhizobium radiobacter F2 and Bacillus sphaeicus F6, was investigated with regard to its production and flocculating properties. The optimization of the culture medium constituents including carbon source,nitrogen source and C / N ratio,metal ions and ionic strength on CBF production were studied. Flocculating properties of CBF were examined by a series of experiments and CBF had good flocculating activities in kaolin suspension with divalent cations and stable over wide range of p H. Studies of the flocculating properties revealed that the flocculation could be stimulated by cations Ca2+,Mg2+,Fe2+,Al3+and Fe3+. In addition,it was stable at 4-30 ℃ in the presence of Ca Cl2. It was found to be effective for flocculation of a kaolin suspension under neutral and weak alkaline conditions( p H 7. 0- 9. 0),and flocculating activities of higher than 95% were obtained when the CBF concentrations among 6- 14 mg / L at p H 8. 0. The results of this study indicate that CBF is a potential replacement of conventional synthetic flocculants and is widely applied in water treatment and downstream processing of food and fermentation industries.展开更多
Lead and cadmium in herbal medicines are highly toxic to living organisms even in low concentrations. An effective method is developed for analysis of trace lead and cadmium in Chinese herbal medicines and their decoc...Lead and cadmium in herbal medicines are highly toxic to living organisms even in low concentrations. An effective method is developed for analysis of trace lead and cadmium in Chinese herbal medicines and their decoctions by graphite furnace atomic absorption spectrometry (GFAAS). The effects of analytical conditions on absorbance were investigated and optimized. A water-dissolving capability for Pb and Cd was investigated, and the contents of different species in five Chinese herbal medicines and their decoctions were analyzed. The content ratios (kow) of n-octanol-soluble Pb or Cd to water-soluble Pb or Cd were evaluated, and the distribution of Pb and Cd in water decoction at stomach and intestine acidities was developed, in the first time. The contents of water-soluble Pb and Cd, n-octanol-soluble Pb and Cd, and their content ratios were related with the kind of medicine and the acidity of the decoction. The proposed method has the advantages of simple operation, high sensitivity and high speed, with 3 σ detection limits of 4.2 pg for Pb and 0.1 pg for Cd.展开更多
In this paper, through the analysis of the causes and status of international accounting standards, and convergence with International Financial Reporting Standards States progress, we draw that international converge...In this paper, through the analysis of the causes and status of international accounting standards, and convergence with International Financial Reporting Standards States progress, we draw that international convergence of accounting is the trend and accounting convergence is an international coordination process, whose essence is the interests of the dispute while countries must participate. In this environment, the implementation of good accounting standards and grasping the professional ethics of the accounting staffhave also become a factor in the industry that can not be ignored.展开更多
With integration of large-scale renewable energy,new controllable devices,and required reinforcement of power grids,modern power systems have typical characteristics such as uncertainty,vulnerability and openness,whic...With integration of large-scale renewable energy,new controllable devices,and required reinforcement of power grids,modern power systems have typical characteristics such as uncertainty,vulnerability and openness,which makes operation and control of power grids face severe security challenges.Application of artificial intelligence(AI)technologies represented by machine learning in power grid regulation is limited by reliability,interpretability and generalization ability of complex modeling.Mode of hybrid-augmented intelligence(HAI)based on human-machine collaboration(HMC)is a pivotal direction for future development of AI technology in this field.Based on characteristics of applications in power grid regulation,this paper discusses system architecture and key technologies of human-machine hybrid-augmented intelligence(HHI)system for large-scale power grid dispatching and control(PGDC).First,theory and application scenarios of HHI are introduced and analyzed;then physical and functional architectures of HHI system and human-machine collaborative regulation process are proposed.Key technologies are discussed to achieve a thorough integration of human/machine intelligence.Finally,state-of-theart and future development of HHI in power grid regulation are summarized,aiming to efficiently improve the intelligent level of power grid regulation in a human-machine interactive and collaborative way.展开更多
Transcription activator-like effectors （TALEs） from Xanthomonas sp. have been used as customizable DNA- binding modules for genome-engineering applications, Ralstonia solanacearum TALE-like proteins （RTLs） exhibit...Transcription activator-like effectors （TALEs） from Xanthomonas sp. have been used as customizable DNA- binding modules for genome-engineering applications, Ralstonia solanacearum TALE-like proteins （RTLs） exhibit similar structural features to TALEs, including a central DNA-binding domain composed of 35 amino acid-long repeats. Here, we characterize the RTLs and show that they localize in the plant cell nucleus, mediate DNA binding, and might function as transcriptional activators. RTLs have a unique DNA-binding architecture and are enriched in repeat variable di-residues （RVDs）, which determine repeat DNA-binding specificities. We determined the DNA-binding specificities for the RVD sequences ND, HN, NP, and NT. The RVD ND mediates highly specific interactions with C nucleotide, HN interacts spe- cifically with A and G nucleotides, and NP binds to C, A, and G nucleotides. Moreover, we developed a highly efficient repeat assembly approach for engineering RTL effectors. Taken together, our data demonstrate that RTLs are unique DNA-targeting modules that are excellent alternatives to be tailored to bind to user-selected DNA sequences for targeted genomic and epigenomic modifications. These findings will facilitate research concerning RTL molecular biology and RTL roles in the pathogenicity of Ralstonia spp.展开更多
In eukaryotes,N-ethylmaleimide-sensitive factor(NSF)is a conserved AAA+ATPase and a key component of the membrane trafficking machinery that promotes the fusion of secretory vesicles with target membranes.Here,we demo...In eukaryotes,N-ethylmaleimide-sensitive factor(NSF)is a conserved AAA+ATPase and a key component of the membrane trafficking machinery that promotes the fusion of secretory vesicles with target membranes.Here,we demonstrate that the Arabidopsis thaliana genome contains a single copy of NSF,At NSF,which plays an essential role in the regulation of leaf serration.The At NSF knock-down mutant,atnsf-1,exhibited more serrations in the leaf margin.Moreover,polar localization of the PINFORMED1(PIN1)auxin efflux transporter was diffuse around the margins of atnsf-1 leaves and root growth was inhibited in the atnsf-1 mutant.More PIN1-GFP accumulated in the intracellular compartments of atnsf-1 plants,suggesting that At NSF is required for intracellular trafficking of PIN between the endosome and plasma membrane.Furthermore,the serration phenotype was suppressed in the atnsf-1 pin1-8 double mutant,suggesting that At NSF is required for PIN1-mediated polar auxin transport to regulate leaf serration.The CUPSHAPED COTYLEDON2(CUC2)transcription factor gene is up-regulated in atnsf-1 plants and the cuc2-3 single mutant exhibits smooth leaf margins,demonstrating that At NSF also functions in the CUC2 pathway.Our results reveal that At NSF regulates the PIN1-generated auxin maxima with a CUC2-mediated feedback loop to control leaf serration.展开更多
CELL DIVISION CONTROL PROTEIN48(CDC48)is essential for membrane fusion,protein degradation,and other cellular processes.Here,we revealed the crucial role of CDC48B in regulating periclinal cell division in roots by an...CELL DIVISION CONTROL PROTEIN48(CDC48)is essential for membrane fusion,protein degradation,and other cellular processes.Here,we revealed the crucial role of CDC48B in regulating periclinal cell division in roots by analyzing the recessive gen1 mutant.We identified the GEN1 gene through map-based cloning and verified that GEN1 encodes CDC48B.gen1 showed severely inhibited root growth,increased periclinal cell division in the endodermis,defective middle cortex(MC)formation,and altered ground tissue patterning in roots.Consistent with these phenotypes,CYCLIND 6;1(CYCD6;1),a periclinal cell division marker,was upregulated in gen1 compared to Col-0.The ratio of SHR_(pro):SHR-GFP fluorescence in pre-dividing nuclei versus the adjacent stele decreased by 33%in gen1,indicating that the trafficking of SHORT-ROOT(SHR)decreased in gen1 when endodermal cells started to divide.These findings suggest that the loss of function of CDC48B inhibits the intercellular trafficking of SHR from the stele to the endodermis,thereby decreasing SHR accumulation in the endodermis.These findings shed light on the crucial role of CDC48B in regulating periclinal cell division in roots.展开更多
Background:Nucleic acid amplification enhancers suitable for use in a recombinase-aided amplification(RAA)assay were studied for the first time,and amplification of a long-fragment(509 bp)was initially explored.Method...Background:Nucleic acid amplification enhancers suitable for use in a recombinase-aided amplification(RAA)assay were studied for the first time,and amplification of a long-fragment(509 bp)was initially explored.Methods:Using recombinant plasmids and clinical samples,RAA fluorescence and basic methods were used to evaluate the efficacy.The fluorescence method was evaluated by threshold time and fluorescence value,and the basic method was characterized by 2%agarose gel electrophoresis.Results:Taking a previously established RAA assay for HPV18 as an example,we demonstrated that the addition of 0.2 M,0.4 M,and 0.6 M betaine and 10%pullulan could enhance the RAA.The new RAA assays with betaine and pullulan were named B-RAA and P-RAA,respectively.Using the B-RAA and P-RAA fluorescence methods,the threshold time values could be shortened by 1.72-2.32 minutes and 2.60 minutes,respectively,and the fluorescence values could be enhanced by 8847.25-9094.37 mv and 5250 mv,respectively.Using the basic method,the sensitivity could be increased 10-fold.We successfully amplified a long-fragment of 509 bp using a P-RAA assay with a sensitivity of 102 copies/μL(compared with 103 copies/μL in the RAA assay).Conclusions:Thus,we concluded that betaine and pullulan are effective additives to enhance the sensitivity of RAA assays.展开更多
基金co-supported by the National Natural Science Foundation of China(Nos.62001387,61901379)the Natural Science Basic Research Plan in Shaanxi Province(No.2019JQ253)+4 种基金the Key R&D Plan of Shaanxi Province(No.2020GY034)the Aerospace Science and Technology Innovation Fund of China Aerospace Science and Technology Corporationthe Shanghai Aerospace Science and Technology Innovation Fund(No.SAST2018045)the China Fundamental Research Fund for the Central Universities(No.3102018QD096)the Seed Foundation of Innovation and Creation for Graduate Students in Northwestern Polytechnical University(No.CX2020152)。
文摘Unmanned Aerial Vehicles(UAVs)enabled Aerial Base Stations(UABSs)have been studied widely in future communications.However,there are a series of challenges such as interference management,trajectory design and resource allocation in the scenarios of multi-UAV networks.Besides,different performances among UABSs increase complexity and bring many challenges.In this paper,the joint downlink transmission power control and trajectory design problem in multi-type UABSs communication network is investigated.In order to satisfy the signal to interference plus noise power ratio of users,each UABS needs to adjust its position and transmission power.Based on the interactions among multiple communication links,a non-cooperative Mean-Field-Type Game(MFTG)is proposed to model the joint optimization problem.Then,a Nash equilibrium solution is solved by two steps:first,the users in the given area are clustered to get the initial deployment of the UABSs;second,the Mean-Field Q(MFQ)-learning algorithm is proposed to solve the discrete MFTG problem.Finally,the effectiveness of the approach is verified through the simulations,which simplifies the solution process and effectively reduces the energy consumption of each UABS.
基金supported in part by the National Natural Science Foundation of China under Grant 61901378,61941119,61901379in part by the Natural Science Basic Research Plan in Shaanxi Province of China under Grant 2019JQ-253+5 种基金in part by the open research fund of National Mobile Communications Research Laboratory,Southeast University under Grant 2020D04in part by China Postdoctoral Science Foundation under Grant BX20190287in part by the Aerospace Science and Technology Innovation Fund of China Aerospace Science and Technology Corporationin part by the Shanghai Aerospace Science and Technology Innovation Fund(No.SAST2018045)in part by the China Fundamental Research Fund for the Central Universities(No.3102018QD096)in part by the Seed Foundation of Innovation and Creation for Graduate Students in Northwestern Polytechnical University(No.CX2020152).
文摘Reconfigurable intelligent surface(RIS)has been proposed as a potential solution to improve the coverage and spectrum efficiency for future wireless communication.However,the privacy of users’data is often ignored in previous works,such as the user’s location information during channel estimation.In this paper,we propose a privacy-preserving design paradigm combining federated learning(FL)with RIS in the mmWave communication system.Based on FL,the local models are trained and encrypted using the private data managed on each local device.Following this,a global model is generated by aggregating them at the central server.The optimal model is trained for establishing the mapping function between channel state information(CSI)and RIS’configuration matrix in order to maximize the achievable rate of the received signal.Simulation results demonstrate that the proposed scheme can effectively approach to the theoretical value generated by centralized machine learning(ML),while protecting user’privacy.
基金the National Nature Science Foundation of China, No. 30973092"Xingwei" Project Medical Emphasis Grant from Jiangsu Province, No. RC2007062
文摘Recent studies regarding neuronal differentiation of mesenchymal stem cells （MSCs） have primarily focused on induction methods and transplantation in vivo. However, knowledge about the intrinsic regulatory mechanisms underlying neuronal induction of MSCs remains limited and unclear. OBJECTIVE： To elucidate the role of JAK-STAT3 signaling pathway during neuronal differentiation of MSCs using a combination of the JAK-STAT3 signaling inhibitor AG490 and growth factors. DESIGN, TIME AND SETTING： Neural, molecular, biomedical, in vitro experiment was performed at the Laboratory of Pharmacology, School of Pharmacy, Nanjing Medical University between March and December 2008 MATERIALS： An inhibitor of the JAK-STAT3 signaling pathway was purchased from Calbiochem, USA. Antibody kit for total and phosphorylated STAT3 was purchased from Cell Signaling, USA. METHODS： MSCs from passage 3 were assigned to non-induced, growth factor, and AG490 groups. MAIN OUTCOME MEASURE： The number of cells expressing neuron-specific enolase, microtubule-associated protein, and glial fibrillary acidic protein were determined by immunocytochemistry. Total and phosphorylated （Tyr705） expression levels of STAT3 protein were measured by Western blot analysis. RESULTS： MSCs were transdifferentiated into neuronal- and astrocyte-like phenotypes through the induction of epidermal growth factor, basic fibroblast growth factor, and brain-derived neurotrophic factor. In addition, the JAK-STAT3 signaling pathway was significantly activated during neural differentiation. Expression of phosphorylated （Tyr705） STAT3 was inhibited with AG490 （5 pmol/L） prior to neural induction with epidermal growth factor, basic fibroblast growth factor, and brain-derived neurotrophic factor; proportion of astrocyte-like cells was significantly reduced （P 〈 0.01）, and the proportion of neuronal-like phenotypes was significantly increased （P〈 0.01）. CONCLUSION： JAK-STAT3 signaling pathway was shown to regulate neuronal induction of bone marrow MSCs. The proportion of MSC-induced neuronal-like cells was increased following treatment with the JAK-STAT3 signaling inhibitor AG490.
基金supported by the National Natural Science Foundation of China(NSFC)(No.62001387)Shanghai Academy of Spaceflight Technology(SAST),China(No.SAST2020124).
文摘Information freshness is a key factor for Internet-of-Things(IoT)to make appropriate decisions and operations.This paper proposes an analytical framework for evaluating the timeliness performance of the IoT system based on Unmanned Aerial Vehicle(UAV)lossy communications.The performance analysis consists of the outage probability analysis and the Age-of-Information(AoI)analysis with outages.To begin with,we solve a lossy coding problem formulated from the UAV communication system,and derive a closed-form expression of the outage probability based on Shannon's lossy source-channel separation theorem.Then,we characterize the Peak AoI(PAoI)for the considered system,and further minimize the PAoI by deriving the optimal rate for generating information.Moreover,we analyze the system performance through theoretical calculations and simulations.The results indicate that the optimal server utilization ratio is always no larger than 0.5.In practical applications,we can utilize the proposed analytical framework to determine the system parameters which guarantee the timeliness performance of UAV lossy communications.
基金supported by the National Key Research and Development Program of China(No.2024YFE0100600)the National Natural Science Foundation of China(No.52373303)+1 种基金the Shanghai Municipal Science and Technology Major Project(No.2021SHZDZX0100)the Fundamental Research Funds for the Central Universities and the Interdisciplinary Joint Research and Development Project of Tongji University(No.2022-4-ZD-01).
文摘Weak interactions prevent the magnetic particles from achieving excellent electromagnetic wave absorp-tion(EMA)at a low filler loading(FL).The construction of one-dimensional magnetic metal fibers(1D-MMFs)contributes to the formation of an electromagnetic(EM)coupling network,enhancing EM properties at a low FL.However,precisely controlling the length of 1D-MMFs to regulate permittivity at low FL poses a challenge.Herein,a novel magnetic field-assisted growth strategy was used to fabricate Co-based fibers with adjustable permittivity and aspect ratios.With a variety of FL changes,centimeter-level Co long fibers(Co-lf)consistently exhibited higher permittivity than Co particles and Co short fibers due to the enhancement of the effective EM coupling.The Co-lf exhibits excellent EMA performance(-54.85 dB,5.8 GHz)at 10 wt.%FL.Meanwhile,heterogeneous interfaces were introduced to increase the interfacial polarization through a fine phosphorylation design,resulting in elevated EMA performances(-51.50 dB,6.6 GHz)at 10 wt.%FL for Co_(2)P/Co long fibers.This study improves the orderliness of the particle arrangement by regulating the length of 1D-MMFs,which affects the behavior of electrons inside the fibers,providing a new perspective for improving the EMA properties of magnetic materials at a low FL.
基金Ministry of Education Supply and Demand Matching Employment Education Project,“Exploration and Practice of School-Enterprise Co-Education of Surveying and Mapping Professionals Under the Background of Industry-Education Integration”(Project No.:2024010250340)。
文摘To promote the achievement of high-quality and full employment goals for students in higher education,this paper analyzes the integration path of practical education and teaching in civil engineering and transportation majors,guided by surveying employment.This paper proposes three integration paths for practical teaching and education in civil engineering and transportation majors under the employment orientation.The first path is to create a modularized and informatized curriculum system.The second path is to deepen diverse cooperative practices between schools and enterprises.The third path is to construct a diversified quality evaluation system for academic achievement.To ensure the quality of education and employment,schools should continuously evaluate and reflect on the practical effects of these three paths to further optimize them.
基金the General Program of National Natural Science Foundation of China,No.30870125
文摘The genes for 5-1ipoxygenase activating protein （ALOX5AP） and phosphodiesterase 4D （PDE4D） have been demonstrated as susceptibility genes for lacunar in the Icelandic and Pakistani populations, but little is known about the role of these genes in Chinese populations. The present study utilized polymerase chain reaction and ligase detection reaction to detect single nucleotide polymorphisms （SNPs） in 280 consecutive stroke patients and 258 unrelated population-based controls from Nanjing, Jiangsu Province, China. The allele frequency, genotypes, and haplotypes of the two SNPs （rs456009 and rs966221） in PDE4D were similar between the two groups. However, A allele frequency of rs4073259 （A/G） and rs4769055 （A/C） in the ALOX5AP gene exhibited differences in two groups, and especially the haplotype of the SNP was significantly different between the two groups. Results suggested that the ALOX5AP gene might be involved in lacunar infarct, while PDE4D gene was not a risk factor for lacunar infarct in individuals from Jiangsu Province, China.
基金The work was supported by the Fundamental Research Funds for the Central Universities Grant3102018QD096in part by the Natural Science Basic Research Plan in Shaanxi Province of China under Grant 2019JQ-075 and Grant 2019JQ-253,and in part by the National Natural Science Foundation of China under Grant 61901379,Grant 61901327,Grant 61825104 and Grant 61631015.
文摘In order to improve the energy efficiency(EE)in the underlay cognitive radio(CR)networks,a power allocation strategy based on an actor-critic reinforcement learning is proposed,where a cluster of cognitive users(CUs)can simultaneously access to the same primary spectrum band under the interference constraints of the primary user(PU),by employing the non-orthogonal multiple access(NOMA)technique.In the proposed scheme,the optimization of the power allocation is formulated as a non-convex optimization problem.Additionally,the power allocation for different CUs is based on the actor-critic reinforcement learning model,in which the weighted data rate is set as the reward function,and the generated action strategy(i.e.the power allocation)is iteratively criticized and updated.Both the CU’s spectral efficiency and the PU’s interference constrains are considered in the training of the actor-critic reinforcement learning.Furthermore,the first order Taylor approximation as well as other manipulations are adopted to solve the power allocation optimization problem for the sake of considering the conventional channel conditions.According to the simulation results,we find that our scheme could achieve a higher spectral efficiency for the CUs compared to a benchmark scheme without learning process as well as the existing Q-learning based method,while the resultant interference affecting the PU transmission can be maintained at a given tolerated limit.
基金supported in part by the Aerospace Science and Technology Innovation Fund of China Aerospace Science and Technology Corporationin part by the Shanghai Aerospace Science and Technology Innovation Fund (No. SAST2018045, SAST2016034, SAST2017049)+1 种基金in part by the China Fundamental Research Fund for the Central Universities (No. 3102018QD096)in part by the Seed Foundation of Innovation and Creation for Graduate Students in Northwestern Polytechnical University (No. ZZ2019024)
文摘In order to improve the physical layer security of the device-to-device(D2D)cellular network,we propose a collaborative scheme for the transmit antenna selection and the optimal D2D pair establishment based on deep learning.Due to the mobility of users,using the current channel state information to select a transmit antenna or establish a D2D pair for the next time slot cannot ensure secure communication.Therefore,in this paper,we utilize the Echo State Network(ESN)to select the transmit antenna and the Long Short-Term Memory(LSTM)to establish the D2D pair.The simulation results show that the LSTMbased and ESN-based collaboration scheme can effectively improve the security capacity of the cellular network with D2D and increase the life of the base station.
基金supported by the Natural Science Foundation of Heilongjiang Province (No. E201461)the National Natural Science Foundation of China (No. 51408200)
文摘In order to evaluate the influence of microbial community structure of seed sludge on the properties of aerobic nitrifying granules, these granules were cultivated with different seed sludge, and the variation of microbial community and dominant bacterial groups that impact the nitrogen removal efficiency of the aerobic nitrifying granules were analyzed and identified using 16 s rDNA sequence and denaturing gradient gel electrophoresis（DGGE） profiles. The results presented here demonstrated that the influence of the community structure of seed sludge on the properties of aerobic nitrifying granules was remarkable, and the granules cultivated by activated sludge from a beer wastewater treatment plant showed better performance, with a stable sludge volume index（SVI） value of 20 m L/g, high extracellular polymeric substance（EPS） content of 183.3 mg/L, high NH4＋-N removal rate of 89.42% and abundant microbial population with 10 dominant bacterial groups. This indicated that activated sludge with abundant communities is suitable for use as seed sludge in culturing aerobic nitrifying granules.
基金supported by National Nature Science Foundation of China (No.62101450)in part by the Shenzhen Science Technology Program,China (No.JCYJ20210324121006017)in part by Key R&D Plan of Shaan Xi Province,China (No.2023YBGY037)。
文摘Future Sixth-Generation (6G) mobile communication networks extremely require the global connectivity and the ground Base Stations (BSs) are difficult to develop in some specific areas,such as mountainous areas.Therefore,the aerial networks are the key framework for the future communications,in which the aerial vehicle could act as the access point.Additionally,Mobile Edge Computing (MEC) is also essential to enhance the data processing capabilities of aerial networks.In this paper,we study a comprehensive communication-computation resource management problem for jointly optimizing user pairing,power and time allocation in the MEC aided Cognitive Radio (CR) aerial networks,namely CR-MEC aerial networks.Explicitly,this multilevel optimization problem could be decomposed into the user pairing and power allocation as well as time allocation sub-problems.In the conceived CR-MEC aerial networks,we propose a User Pairing and Computation Offloading Management Algorithm (UPCOMA) based on three-sided matching theory,aiming to minimize the system’s energy consumption.At the first step of UPCOMA,multiple Primary Users (PUs) and Cognitive Users (CUs) on the ground negotiate to each other with the suitable power allocation coefficients and construct the stable user pairs.Moreover,the stable user pairs would match to a high altitude platform who act as the base station,which is for appropriately allocating Transmission Time Slots (TSs) at the second step of UPCOMA.Additionally,a hybrid offloading mode is proposed in our conceived networks in order to support ground users to offload their tasks adaptively according to their individual deadlines.Furthermore,the simulation results reveal that the relative performance of UPCOMA is close to that of the Brute-Force Search Algorithm (BFSA) with low complexity.Meanwhile,the hybrid offloading mode with less energy consumption supports much more ground user pairs to offload tasks compared to the binary mode.
基金Sponsored by the National High Technology Research and Development Program of China(Grant No.2009AA062906)the"Twelfth Five-Year Plan"National Key Technology R&D Program of China(Grant No.2012BAD14B06-04)+2 种基金the National Natural Science Foundation of China(Grant No.51478140&51408200)State Key Laboratory of Urban Water Resource and Environment(Harbin Institute of Technology)(Grant No.2015DX06)Promising Youngsters Training Program of Heilongjiang University of Science and Technology(Grant No.Q20120201)
文摘A compound bioflocculant CBF,produced by mixed culture of Rhizobium radiobacter F2 and Bacillus sphaeicus F6, was investigated with regard to its production and flocculating properties. The optimization of the culture medium constituents including carbon source,nitrogen source and C / N ratio,metal ions and ionic strength on CBF production were studied. Flocculating properties of CBF were examined by a series of experiments and CBF had good flocculating activities in kaolin suspension with divalent cations and stable over wide range of p H. Studies of the flocculating properties revealed that the flocculation could be stimulated by cations Ca2+,Mg2+,Fe2+,Al3+and Fe3+. In addition,it was stable at 4-30 ℃ in the presence of Ca Cl2. It was found to be effective for flocculation of a kaolin suspension under neutral and weak alkaline conditions( p H 7. 0- 9. 0),and flocculating activities of higher than 95% were obtained when the CBF concentrations among 6- 14 mg / L at p H 8. 0. The results of this study indicate that CBF is a potential replacement of conventional synthetic flocculants and is widely applied in water treatment and downstream processing of food and fermentation industries.
文摘Lead and cadmium in herbal medicines are highly toxic to living organisms even in low concentrations. An effective method is developed for analysis of trace lead and cadmium in Chinese herbal medicines and their decoctions by graphite furnace atomic absorption spectrometry (GFAAS). The effects of analytical conditions on absorbance were investigated and optimized. A water-dissolving capability for Pb and Cd was investigated, and the contents of different species in five Chinese herbal medicines and their decoctions were analyzed. The content ratios (kow) of n-octanol-soluble Pb or Cd to water-soluble Pb or Cd were evaluated, and the distribution of Pb and Cd in water decoction at stomach and intestine acidities was developed, in the first time. The contents of water-soluble Pb and Cd, n-octanol-soluble Pb and Cd, and their content ratios were related with the kind of medicine and the acidity of the decoction. The proposed method has the advantages of simple operation, high sensitivity and high speed, with 3 σ detection limits of 4.2 pg for Pb and 0.1 pg for Cd.
文摘In this paper, through the analysis of the causes and status of international accounting standards, and convergence with International Financial Reporting Standards States progress, we draw that international convergence of accounting is the trend and accounting convergence is an international coordination process, whose essence is the interests of the dispute while countries must participate. In this environment, the implementation of good accounting standards and grasping the professional ethics of the accounting staffhave also become a factor in the industry that can not be ignored.
基金supported by the National Key R&D Program of China(2018AAA0101500).
文摘With integration of large-scale renewable energy,new controllable devices,and required reinforcement of power grids,modern power systems have typical characteristics such as uncertainty,vulnerability and openness,which makes operation and control of power grids face severe security challenges.Application of artificial intelligence(AI)technologies represented by machine learning in power grid regulation is limited by reliability,interpretability and generalization ability of complex modeling.Mode of hybrid-augmented intelligence(HAI)based on human-machine collaboration(HMC)is a pivotal direction for future development of AI technology in this field.Based on characteristics of applications in power grid regulation,this paper discusses system architecture and key technologies of human-machine hybrid-augmented intelligence(HHI)system for large-scale power grid dispatching and control(PGDC).First,theory and application scenarios of HHI are introduced and analyzed;then physical and functional architectures of HHI system and human-machine collaborative regulation process are proposed.Key technologies are discussed to achieve a thorough integration of human/machine intelligence.Finally,state-of-theart and future development of HHI in power grid regulation are summarized,aiming to efficiently improve the intelligent level of power grid regulation in a human-machine interactive and collaborative way.
文摘Transcription activator-like effectors （TALEs） from Xanthomonas sp. have been used as customizable DNA- binding modules for genome-engineering applications, Ralstonia solanacearum TALE-like proteins （RTLs） exhibit similar structural features to TALEs, including a central DNA-binding domain composed of 35 amino acid-long repeats. Here, we characterize the RTLs and show that they localize in the plant cell nucleus, mediate DNA binding, and might function as transcriptional activators. RTLs have a unique DNA-binding architecture and are enriched in repeat variable di-residues （RVDs）, which determine repeat DNA-binding specificities. We determined the DNA-binding specificities for the RVD sequences ND, HN, NP, and NT. The RVD ND mediates highly specific interactions with C nucleotide, HN interacts spe- cifically with A and G nucleotides, and NP binds to C, A, and G nucleotides. Moreover, we developed a highly efficient repeat assembly approach for engineering RTL effectors. Taken together, our data demonstrate that RTLs are unique DNA-targeting modules that are excellent alternatives to be tailored to bind to user-selected DNA sequences for targeted genomic and epigenomic modifications. These findings will facilitate research concerning RTL molecular biology and RTL roles in the pathogenicity of Ralstonia spp.
基金supported by the National Natural Science Foundation of China(31570291,31570246,31872669)Funds of Shandong“Double Tops”Program(SYL2017YSTD03)+6 种基金Shandong“Foreign experts double hundred”Program(WST2017008)Taishan Scholar ProjectDFG(SFB 746)Excel ence Initiative of the German Federal and State Governments(EXC 294)Bundesministerium für Forschung und Technik(BMBF,MICROSYSTEMS)the Deutsches Zentrum für Luft und Raumfahrt(DLR 50WB1022)Natural Science Foundation of Heilongjiang Province(C2016002)。
文摘In eukaryotes,N-ethylmaleimide-sensitive factor(NSF)is a conserved AAA+ATPase and a key component of the membrane trafficking machinery that promotes the fusion of secretory vesicles with target membranes.Here,we demonstrate that the Arabidopsis thaliana genome contains a single copy of NSF,At NSF,which plays an essential role in the regulation of leaf serration.The At NSF knock-down mutant,atnsf-1,exhibited more serrations in the leaf margin.Moreover,polar localization of the PINFORMED1(PIN1)auxin efflux transporter was diffuse around the margins of atnsf-1 leaves and root growth was inhibited in the atnsf-1 mutant.More PIN1-GFP accumulated in the intracellular compartments of atnsf-1 plants,suggesting that At NSF is required for intracellular trafficking of PIN between the endosome and plasma membrane.Furthermore,the serration phenotype was suppressed in the atnsf-1 pin1-8 double mutant,suggesting that At NSF is required for PIN1-mediated polar auxin transport to regulate leaf serration.The CUPSHAPED COTYLEDON2(CUC2)transcription factor gene is up-regulated in atnsf-1 plants and the cuc2-3 single mutant exhibits smooth leaf margins,demonstrating that At NSF also functions in the CUC2 pathway.Our results reveal that At NSF regulates the PIN1-generated auxin maxima with a CUC2-mediated feedback loop to control leaf serration.
基金supported by the National Natural Science Foundation of China (31570291, 31570246)Funds of Shandong “Double Tops” Program (YL2017YSTD03)+3 种基金Shandong “Foreign Experts Double Hundred” Program (WST2017008)Shandong Key Basic Research (ZR2018ZC08N1)Natural Science Foundation of Heilongjiang Province (C2016002)the Fundamental Research Funds for the Central Universities (2572019CT03).
文摘CELL DIVISION CONTROL PROTEIN48(CDC48)is essential for membrane fusion,protein degradation,and other cellular processes.Here,we revealed the crucial role of CDC48B in regulating periclinal cell division in roots by analyzing the recessive gen1 mutant.We identified the GEN1 gene through map-based cloning and verified that GEN1 encodes CDC48B.gen1 showed severely inhibited root growth,increased periclinal cell division in the endodermis,defective middle cortex(MC)formation,and altered ground tissue patterning in roots.Consistent with these phenotypes,CYCLIND 6;1(CYCD6;1),a periclinal cell division marker,was upregulated in gen1 compared to Col-0.The ratio of SHR_(pro):SHR-GFP fluorescence in pre-dividing nuclei versus the adjacent stele decreased by 33%in gen1,indicating that the trafficking of SHORT-ROOT(SHR)decreased in gen1 when endodermal cells started to divide.These findings suggest that the loss of function of CDC48B inhibits the intercellular trafficking of SHR from the stele to the endodermis,thereby decreasing SHR accumulation in the endodermis.These findings shed light on the crucial role of CDC48B in regulating periclinal cell division in roots.
基金supported by grants from the Youth Foundation of Academician Hou Yunde[grant number 2019HYDQNJJ03]China Mega-Projects for Infec-tious Disease[grant number 2017ZX10302301-004-002].
文摘Background:Nucleic acid amplification enhancers suitable for use in a recombinase-aided amplification(RAA)assay were studied for the first time,and amplification of a long-fragment(509 bp)was initially explored.Methods:Using recombinant plasmids and clinical samples,RAA fluorescence and basic methods were used to evaluate the efficacy.The fluorescence method was evaluated by threshold time and fluorescence value,and the basic method was characterized by 2%agarose gel electrophoresis.Results:Taking a previously established RAA assay for HPV18 as an example,we demonstrated that the addition of 0.2 M,0.4 M,and 0.6 M betaine and 10%pullulan could enhance the RAA.The new RAA assays with betaine and pullulan were named B-RAA and P-RAA,respectively.Using the B-RAA and P-RAA fluorescence methods,the threshold time values could be shortened by 1.72-2.32 minutes and 2.60 minutes,respectively,and the fluorescence values could be enhanced by 8847.25-9094.37 mv and 5250 mv,respectively.Using the basic method,the sensitivity could be increased 10-fold.We successfully amplified a long-fragment of 509 bp using a P-RAA assay with a sensitivity of 102 copies/μL(compared with 103 copies/μL in the RAA assay).Conclusions:Thus,we concluded that betaine and pullulan are effective additives to enhance the sensitivity of RAA assays.
