As molecular targets continue to be identified and more targeted inhibitors are developed for personalized treatment of non-small cell lung cancer(NSCLC), multigene mutation determination will be needed for routine on...As molecular targets continue to be identified and more targeted inhibitors are developed for personalized treatment of non-small cell lung cancer(NSCLC), multigene mutation determination will be needed for routine oncology practice and for clinical trials. In this study, we evaluated the sensitivity and specificity of multigene mutation testing by using the Snapshot assay in NSCLC. We retrospectively reviewed a cohort of 110 consecutive NSCLC specimens for which epidermal growth factor receptor(EGFR) mutation testing was performed between November 2011 and December 2011 using Sanger sequencing. Using the Snapshot assay, mutation statuses were detected for EGFR, Kirsten rate sarcoma viral oncogene homolog(KRAS), phosphoinositide-3-kinase catalytic alpha polypeptide(PIK3CA), v-Raf murine sarcoma viral oncogene homolog B1(BRAF), v-ras neuroblastoma viral oncogene homolog(NRAS), dual specificity mitogen activated protein kinase kinase 1(MEK1), phosphatase and tensin homolog(PTEN), and human epidermal growth factor receptor 2(HER2) in patient specimens and cell line DNA. Snapshot data were compared to Sanger sequencing data. Of the 110 samples, 51(46.4%) harbored at least one mutation. The mutation frequency in adenocarcinoma specimens was 55.6%, and the frequencies of EGFR, KRAS, PIK3 CA, PTEN, and MEK1 mutations were 35.5%, 9.1%, 3.6%, 0.9%, and 0.9%, respectively. No mutation was found in the HER2, NRAS, or BRAF genes. Three of the 51 mutant samples harbored double mutations: two PIK3 CA mutations coexisted with KRAS or EGFR mutations, and another KRAS mutation coexisted with a PTEN mutation. Among the 110 samples, 47 were surgical specimens, 60 were biopsy specimens, and 3 were cytological specimens; the corresponding mutation frequencies were 51.1%, 41.7%, and 66.7%, respectively(P = 0.532). Compared to Sanger sequencing, Snapshot specificity was 98.4% and sensitivity was 100%(positive predictive value, 97.9%; negative predictive value, 100%). The Snapshot assay is a sensitive and easily customized assay for multigene mutation testing in clinical practice.展开更多
A priori knowledge of the number of tags is crucial for anti-collision protocols in slotted UHF RFID systems.The number of tags is used to decide optimal frame length in dynamic frame slotted ALOHA(DFSA)and to adjust ...A priori knowledge of the number of tags is crucial for anti-collision protocols in slotted UHF RFID systems.The number of tags is used to decide optimal frame length in dynamic frame slotted ALOHA(DFSA)and to adjust access probability in random access protocols.Conventional researches estimate the number of tags in MAC layer based on statistics of empty slots,collided slots and successful slots.Usually,a collision detection algorithm is employed to determine types of time slots.Only three types are distinguished because of lack of ability to detect the number of tags in single time slot.In this paper,a physical layer algorithm is proposed to detect the number of tags in a collided slot.Mean shift algorithm is utilized,and some properties of backscatter signals are investigated.Simulation results verify the effectiveness of the proposed solution in terms of low estimation error with a high SNR range,outperforming the existing MAC layer approaches.展开更多
Grain growth directly influences the plasticity and strength of Mg alloys.As the grain size decreases from the microscale to the nanoscale,the plasticity of Mg alloys continually increases,whereas the strength first i...Grain growth directly influences the plasticity and strength of Mg alloys.As the grain size decreases from the microscale to the nanoscale,the plasticity of Mg alloys continually increases,whereas the strength first increases and later decreases.These trends are observed because the plastic deformation mechanism changes from dislocation–twinning dominance to grain boundary dominance.In this study,the factors influencing grain growth,such as the temperature of plastic deformation/annealing,second-phase particles and solute atoms,are examined to aid effective control of the grain size.Additionally,the mechanisms of grain growth,typically induced by strain and thermal activation,are clarified.Strain-induced grain boundary migration is attributable to the difference in the strain energy stored in adjacent grains with high-density dislocations.Heat-induced grain boundary migration is driven by the difference in the energy of the grain boundary/subgrain boundary and boundary curvature.Abnormal grain growth can be induced by anisotropy of the strain energy,anisotropy of the grain boundary mobility,depinning of the second phase and high misorientation gradient.展开更多
Recently,object identification with radio frequency identification(RFID)technology is becoming increasingly popular.Identification time is a key performance metric to evaluate the RFID system.The present paper analyze...Recently,object identification with radio frequency identification(RFID)technology is becoming increasingly popular.Identification time is a key performance metric to evaluate the RFID system.The present paper analyzes the deficiencies of the state-of-the-arts algorithms and proposes a novel sub-frame-based algorithm with adaptive frame breaking policy to lower the tag identification time for EPC global C1 Gen2 UHF RFID standard.Through the observation of slot statistics in a sub-frame,the reader estimates the tag quantity and efficiently calculates an optimal frame size to fit the unread tags.Only when the expected average identification time in the calculated frame size is less than that in the previous frame size,the reader starts the new frame.Moreover,the estimation of the proposed algorithm is implemented by the look-up tables,which allows dramatically reduction in the computational complexity.Simulation results show noticeable throughput and time efficiency improvements of the proposed solution over the existing approaches.展开更多
The nonlinear dynamic behaviors of viscoelastic axially functionally graded material(AFG)pipes conveying pulsating internal flow are very complex.And the dynamic behavior will induce the failure of the pipes,and resea...The nonlinear dynamic behaviors of viscoelastic axially functionally graded material(AFG)pipes conveying pulsating internal flow are very complex.And the dynamic behavior will induce the failure of the pipes,and research of vibration and stability of pipes becomes a major concern.Considering that the elastic modulus,density,and coefficient of viscoelastic damping of the pipe material vary along the axial direction,the transverse vibration equation of the viscoelastic AFG pipe conveying pulsating fluid is established based on the Euler-Bernoulli beam theory.The generalized integral transform technique(GITT)is used to transform the governing fourth-order partial differential equation into a nonlinear system of fourth-order ordinary differential equations in time.The time domain diagram,phase portraits,Poincarémap and power spectra diagram at different dimensionless pulsation frequencies,are discussed in detail,showing the characteristics of chaotic,periodic,and quasi-periodic motion.The results show that the distributions of the elastic modulus,density,and coefficient of viscoelastic damping have significant effects on the nonlinear dynamic behavior of the viscoelastic AFG pipes.With the increase of the material property coefficient k,the transition between chaotic,periodic,and quasi-periodic motion occurs,especially in the high-frequency region of the flow pulsation.展开更多
We investigate how the splicing mode of a holographic element(hogel)affects the reconstruction of a 3 D scene to improve the reconstruction resolution of a holographic stereogram fabricated using the effective perspec...We investigate how the splicing mode of a holographic element(hogel)affects the reconstruction of a 3 D scene to improve the reconstruction resolution of a holographic stereogram fabricated using the effective perspective image segmentation and mosaicking method(EPISM).First,the effect of hogel spatial multiplexing on holographic recording and reconstruction is studied based on the mechanism of recording interference fringes in the holographic recording medium.Second,combined with the influence of multiple exposures on the hologram's diffraction efficiency,the diffraction efficiency of the holographic stereogram is analyzed in the spatial multiplexing mode.The holographic stereogram is then regarded as a special optical imaging system.The theory of spatial bandwidth product is adopted to describe the comprehensive resolution of the holographic stereogram,which explains why hogel spatial multiplexing can significantly improve the reconstruction resolution of a holographic stereogram.Compared with the traditional printing method under the same parameters in optical experiments,hogel spatial multiplexing has a lower diffraction efficiency but a higher quality of reconstructed image,consistent with the theoretical analysis.展开更多
In this paper,a dynamic multi-ary query tree(DMQT)anti-collision protocol for Radio Frequency Identification(RFID)systems is proposed for large scale passive RFID tag identification.The proposed DMQT protocol is based...In this paper,a dynamic multi-ary query tree(DMQT)anti-collision protocol for Radio Frequency Identification(RFID)systems is proposed for large scale passive RFID tag identification.The proposed DMQT protocol is based on an iterative process between the reader and tags which identifies the position of collision bits through map commands and dynamically encodes them to optimize slots allocation through query commands.In this way,the DMQT completely eliminates empty slots and greatly reduces collision slots,which in turn reduces the identification time and energy costs.In addition and differently to other known protocols,the DMQT does not need to estimate the number of tags,reducing the protocol implementation complexity and eliminating the uncertainty caused by the estimation algorithm.A numerical analysis shows that DMQT has better performance than other algorithms for a number of tags larger than 300.Meanwhile,when the number of tags is 2000 and the tag identity(ID)length is 128 bits,the total identification time is 2.58 s and the average energy cost for a tag identification is 1.2 mJ,which are 16.9%and 10.4%less than those of state-of-the-art algorithms,respectively.In addition,a DMQT extension based on ACK command has also been presented to deal with capture effect and avoid missing identification.展开更多
Brain tumor is one of the most common tumors with high mortality.Early detection is of great significance for the treatment and rehabilitation of patients.The single channel convolution layer and pool layer of traditi...Brain tumor is one of the most common tumors with high mortality.Early detection is of great significance for the treatment and rehabilitation of patients.The single channel convolution layer and pool layer of traditional convolutional neural network(CNN)structure can only accept limited local context information.And most of the current methods only focus on the classification of benign and malignant brain tumors,multi classification of brain tumors is not common.In response to these shortcomings,considering that convolution kernels of different sizes can extract more comprehensive features,we put forward the multi-size convolutional kernel module.And considering that the combination of average-pooling with max-pooling can realize the complementary of the high-dimensional information extracted by the two structures,we proposed the dual-channel pooling layer.Combining the two structures with ResNet50,we proposed an improved ResNet50 CNN for the applications in multi-category brain tumor classification.We used data enhancement before training to avoid model over fitting and used five-fold cross-validation in experiments.Finally,the experimental results show that the network proposed in this paper can effectively classify healthy brain,meningioma,diffuse astrocytoma,anaplastic oligodendroglioma and glioblastoma.展开更多
What is already known on this topic?Smoking is the primary risk factor for a poor prognosis in chronic respiratory disease(CRD).Current tobacco surveillance efforts in China focus on the general population and do not ...What is already known on this topic?Smoking is the primary risk factor for a poor prognosis in chronic respiratory disease(CRD).Current tobacco surveillance efforts in China focus on the general population and do not adequately cover CRD patients.What is added by this report?We employed electronic medical records(EMR)to track smoking habits in 28,334 hospitalized CRD patients at Beijing Chao-Yang Hospital.The rates of former and current smokers were 30.7%and 18.0%,respectively.Both former and current smokers exhibited an increased risk of respiratory symptoms and extended hospital stays.What are the implications for public health practice?These results underscore the importance of implementing smoking monitoring and targeted cessation interventions for hospitalized patients with CRDs.展开更多
Background: Available study revealed advanced tumors have a higher expression rate of MAGE-A3 gene which has a lot of single nucleotide polymorphism(SNP) loci with polymorphisms. This study aimed to analyze the all...Background: Available study revealed advanced tumors have a higher expression rate of MAGE-A3 gene which has a lot of single nucleotide polymorphism(SNP) loci with polymorphisms. This study aimed to analyze the allele frequency of SNP loci in MAGE-A3 gene and investigate the relationship between MAGE-A3 gene polymorphisms and clinical factors.Methods: Tumor samples of a cohort of 191 NSCLC patients were collected. EGFR m RNA expression were detected by q RT-PCR. SNPs in whole length of MAGE-A3 gene were detected by direct sequencing. Frequencies of the SNPs were correlated to gene expression, mutation status of EGFR and clinical factors.Results: Sequencing analysis confirmed that allele frequencies of genotypes on SNP loci rs5970360, rs5925210, rs5970361, rs5925211 and rs35123853 were CC(0.681)/CT(0.319), CC(0.660)/CG(0.340), CC(0.681)/CA(0.319), AA(0.984)/AT(0.016) and GG(1.000)/GA(0.000), respectively, which were different from the frequencies and genotypes of MAGE-A3 in SNP database. Chi-square tests showed the EGFR mR NA expression level had significant correlation with the genotypes of SNP loci rs5970360 and rs5925210. But all frequencies of each MAGE-A3 SNPs were not found significantly different between EGFR mutant and wild type patients. MAGE-A3 gene polymorphisms had no significant effects on survival of NSCLC patients.Conclusions: Chinese patients with NSCLC had different SNP patterns of MAGE-A3 in comparison with those in international SNP database. These MAGE-A3 SNP loci might have not prognostic significance. MAGE-A3 SNP loci rs5970360 and rs5925210 might be predictive for EGFR m RNA expression levels and helpful to the selection of patients for epidermal growth factor receptor(EGFR) targeted immunotherapy.展开更多
Magnetic skyrmions in multilayer structures are considered as a new direction for the next generation of storage due to their small size,strong anti-interference ability,high current-driven mobility,and compatibility ...Magnetic skyrmions in multilayer structures are considered as a new direction for the next generation of storage due to their small size,strong anti-interference ability,high current-driven mobility,and compatibility with existing spintronic technology.In this work,we present a tunable room temperature skyrmion platform based on multilayer stacks of MgO/FeNiB/Mo.We systematically studied the creation of magnetic skyrmions in MgO/FeNiB/Mo multilayer structures with perpendicular magnetic anisotropy(PMA).In these structures,the magnetic anisotropy changes from PMA to in-plane magnetic anisotropy(IMA)as the thickness of FeNiB layer increases.By adjusting the applied magnetic field and electric current,stable and high-density skyrmions can be obtained in the material system.The discovery of this material broadens the exploration of new materials for skyrmion and promotes the development of spintronic devices based on skyrmions.展开更多
We fabricated monolayer n-type two-dimensional crystalline semiconducting films with millimeter-sized areas and remarkable morphological uniformity using an antisolvent-confined spin-coating method.The antisolvent can...We fabricated monolayer n-type two-dimensional crystalline semiconducting films with millimeter-sized areas and remarkable morphological uniformity using an antisolvent-confined spin-coating method.The antisolvent can cause a downstream Marangoni flow,which improves the film morphologies.The deposited crystalline monolayer films exhibit excellent thermal stabilities after annealing,which reveals the annealing-induced enhancement of crystallinity.The transistors based on the n-type monolayer crystalline films show linear output characteristics and superior electron mobilities.The improved charge injection between monolayer films and Au electrodes results from the energy level shift as the films decrease to the monolayer,which leads to a lower injection barrier.This work demonstrates a promising method for fabricating air-stable,low-cost,high-performance,and large-area organic electronics.展开更多
SRUHSC⁃RC(Steel Reinforced Ultra High Strength Concrete⁃Reinforced Concrete)structures are used extensively in super high⁃rise buildings.However,it has obvious brittleness.Wrapping structural steel inside is a good wa...SRUHSC⁃RC(Steel Reinforced Ultra High Strength Concrete⁃Reinforced Concrete)structures are used extensively in super high⁃rise buildings.However,it has obvious brittleness.Wrapping structural steel inside is a good way to alleviate the brittleness problem.The purpose of this study is to investigate seismic behavior of SRUHSC⁃RC exterior joints on the basis of experimental results of eleven specimens under the reversed cyclic loading.The relationship among the force⁃displacement curve,ductility,energy dissipation property,strength degradation,stiffness degradation,the strains of steel bone and stirrup at the core area of the joint were analyzed based on the test results.It is shown that axial compression ratio and stirrup volumetric ratio have significant effects on the shear behavior of SRUHSC⁃RC frame exterior joints.The general requirement on the axial⁃load level and the amount of confinement stirrup for the joints in the design is suggested.展开更多
BACKGROUND Type 1 diabetes(T1D)is a severe and prevalent metabolic disease.Due to its high heredity,an increasing number of genome-wide association studies have been performed,most of which were from hospital-based ca...BACKGROUND Type 1 diabetes(T1D)is a severe and prevalent metabolic disease.Due to its high heredity,an increasing number of genome-wide association studies have been performed,most of which were from hospital-based case-control studies with a relatively small sample size.The association of single nucleotide polymorphisms(SNPs)and T1D has been less studied and is less understood in natural cohorts.AIM To investigate the significant variants of T1D,which could be potential biomarkers for T1D prediction or even therapy.METHODS A genome-wide association study(GWAS)of adult T1D was performed in a nested case-control study(785 cases vs 804 controls)from a larger 5-year cohort study in Suzhou,China.Potential harmful or protective SNPs were evaluated for T1D.Subsequent expression and splicing quantitative trait loci(eQTL and sQTL)analyses were carried out to identify target genes modulated by these SNPs.RESULTS A harmful SNP for T1D,rs3117017[odds ratio(OR)=3.202,95%confidence interval(CI):2.296-4.466,P=9.33×10-4]and three protective SNPs rs55846421(0.113,0.081-0.156,1.76×10-9),rs75836320(0.283,0.205-0.392,1.07×10-4),rs362071(0.568,0.495-0.651,1.66×10-4)were identified.Twenty-two genes were further identified as potential candidates for T1D onset.CONCLUSION We identified a potential genetic basis of T1D,both protective and harmful,using a GWAS in a larger nested case-control study of a Chinese population.展开更多
This paper uses the ARMA model method to fit the data of the urban and the rural residents’ per capita income in China and builds the MA(2) and AR(2) model. With the model, this paper predicts their trends in 5 years...This paper uses the ARMA model method to fit the data of the urban and the rural residents’ per capita income in China and builds the MA(2) and AR(2) model. With the model, this paper predicts their trends in 5 years, also uses the prediction to analyze the income gap. The results show that in the next 5 years, the rural and the urban residents’ per capita income will be increasing steadily, but the level remains very low, the income gap is still large.展开更多
In this paper, the boundary layer equations (abbreviation BLE) for exterior flow around an obstacle are established using semi-geodesic coordinate system (S-coordinate) based on the curved two dimensional surface of t...In this paper, the boundary layer equations (abbreviation BLE) for exterior flow around an obstacle are established using semi-geodesic coordinate system (S-coordinate) based on the curved two dimensional surface of the obstacle. BLE are nonlinear partial differential equations on unknown normal viscous stress tensor and pressure on the obstacle and the existence of solution of BLE is proved. In addition a dimensional split method for dimensional three Navier-Stokes equations is established by applying several 2D-3C partial differential equations on two dimensional manifolds to approach 3D Navier-Stokes equations. The examples for the exterior flow around spheroid and ellipsoid are presents here.展开更多
[Objectives]To establish HPLC finger-print of Marchantia convolute Gao et Chang,and to control the quality of medicinal materials. [Methods] Agilent ZORBAX SB-C18 chromatographic column( 4. 6 mm × 250 mm,5μm) wa...[Objectives]To establish HPLC finger-print of Marchantia convolute Gao et Chang,and to control the quality of medicinal materials. [Methods] Agilent ZORBAX SB-C18 chromatographic column( 4. 6 mm × 250 mm,5μm) was adopted,acetonitrile( B)-0. 1% phosphoric solution( D) was used as the mobile phase( gradient elution),and the detection was conducted at the wavelength of 230 nm and at the column temperature of 25℃. HPLC finger-print of herb materials in the upland-field was established,and 8 lots of medicinal materials were used for the similarity assessment to establish the finger-print. [Results] Theprecision,repeatability and stability RSD of HPLC finger-prints of the 8 lots of Marchantia convoluta Gao et Chang were all less than 3%,and their similarities were all greater than 0. 75; 6 common peaks were observed,and the control finger-print was also established. [Conclusions] With reliable data and simple and efficient manipulations,HPLC finger-print analysis can provide references for the quality assessment of Marchantia convoluta Gao et Chang.展开更多
With the development of nanobiotechnology,the carbon nanotubes(CNTs)and protein hybrids system has attracted an increasing attention for great potential application in nanotechnology,medicine,smart materials,light ind...With the development of nanobiotechnology,the carbon nanotubes(CNTs)and protein hybrids system has attracted an increasing attention for great potential application in nanotechnology,medicine,smart materials,light industry,and biology.In this review,the main preparation processes,impact factors,measurement of interactions and potential applications of CNTs/protein are presented from the aspect of experiments.Meanwhile,the proper forces detection methods are illustrated comprehensively to complete the quantitative measurement.Atomic force microscope(AFM)and surface force apparatus(SFA)experiments are described in detail to confirm the powerful function in measuring the interaction forces.In addition,the impact of different protein structures(amino acid residues,αHelix,polypeptide chain,and assembled subunits)on interactions between CNTs and protein is presented and different amino acid residues may intervene largely on interactions.Owing to the relatively little knowledge about the structure,function,and spatial orientation of proteins interaction with CNTs surface,we assume that the key problem is how to prepare CNTs and protein specimen with unique structure(such as the variation of secondary and tridimensional structure of protein or the single CNTs)to investigate the interaction forces instead of the designed,preparation,and detection methods.展开更多
The laparoendoscopic single-site (LESS) technique is the latest technical innovation in laparoscopic surgery to undergo exponential development in urology. This study undertaken to illustrate our initial experience ...The laparoendoscopic single-site (LESS) technique is the latest technical innovation in laparoscopic surgery to undergo exponential development in urology. This study undertaken to illustrate our initial experience LESS radical prostatectomy (RP) and analyze early outcomes. Nineteen patients diagnosed with prostate cancer underwent LESS-RP in our institute. The patients were divided into two groups: conventional LESS and transurethral assistant LESS. Preoperative, perioperative, postoperative, pathologic, and functional outcomes data were assessed. With the help of a transurethral assistant, the mean operation and anastomosis time were decreased markedly. No focal positive margins were encountered. No prostate-specific antigen recurrence was detected 1 month postoperatively. Complete continence recovery (no pad) was observed in 32% of the patients at 1 month after the operation. No intraoperative and postoperative complications were reported, LESS-RP is a feasible and effective surgical procedure for treatment of prostate cancer. Moreover, transurethral assistant LESS could reduce the difficulty of LESS-RP and shorten the operation time.展开更多
文摘As molecular targets continue to be identified and more targeted inhibitors are developed for personalized treatment of non-small cell lung cancer(NSCLC), multigene mutation determination will be needed for routine oncology practice and for clinical trials. In this study, we evaluated the sensitivity and specificity of multigene mutation testing by using the Snapshot assay in NSCLC. We retrospectively reviewed a cohort of 110 consecutive NSCLC specimens for which epidermal growth factor receptor(EGFR) mutation testing was performed between November 2011 and December 2011 using Sanger sequencing. Using the Snapshot assay, mutation statuses were detected for EGFR, Kirsten rate sarcoma viral oncogene homolog(KRAS), phosphoinositide-3-kinase catalytic alpha polypeptide(PIK3CA), v-Raf murine sarcoma viral oncogene homolog B1(BRAF), v-ras neuroblastoma viral oncogene homolog(NRAS), dual specificity mitogen activated protein kinase kinase 1(MEK1), phosphatase and tensin homolog(PTEN), and human epidermal growth factor receptor 2(HER2) in patient specimens and cell line DNA. Snapshot data were compared to Sanger sequencing data. Of the 110 samples, 51(46.4%) harbored at least one mutation. The mutation frequency in adenocarcinoma specimens was 55.6%, and the frequencies of EGFR, KRAS, PIK3 CA, PTEN, and MEK1 mutations were 35.5%, 9.1%, 3.6%, 0.9%, and 0.9%, respectively. No mutation was found in the HER2, NRAS, or BRAF genes. Three of the 51 mutant samples harbored double mutations: two PIK3 CA mutations coexisted with KRAS or EGFR mutations, and another KRAS mutation coexisted with a PTEN mutation. Among the 110 samples, 47 were surgical specimens, 60 were biopsy specimens, and 3 were cytological specimens; the corresponding mutation frequencies were 51.1%, 41.7%, and 66.7%, respectively(P = 0.532). Compared to Sanger sequencing, Snapshot specificity was 98.4% and sensitivity was 100%(positive predictive value, 97.9%; negative predictive value, 100%). The Snapshot assay is a sensitive and easily customized assay for multigene mutation testing in clinical practice.
基金This work was supported in part by the National Natural Science Foundation of China under project contracts[NOS.61601093,61791082,61701116,61371047]in part by Sichuan Provincial Science and Technology Planning Program of China under project contracts No.2016GZ0061 and No.2018HH0044+2 种基金in part by Guangdong Provincial Science and Technology Planning Program of China under project contracts No.2015B090909004 and No.2016A010101036in part by the fundamental research funds for the Central Universities under project contract No.ZYGX2016Z011in part by Science and Technology on Electronic Information Control Laboratory.
文摘A priori knowledge of the number of tags is crucial for anti-collision protocols in slotted UHF RFID systems.The number of tags is used to decide optimal frame length in dynamic frame slotted ALOHA(DFSA)and to adjust access probability in random access protocols.Conventional researches estimate the number of tags in MAC layer based on statistics of empty slots,collided slots and successful slots.Usually,a collision detection algorithm is employed to determine types of time slots.Only three types are distinguished because of lack of ability to detect the number of tags in single time slot.In this paper,a physical layer algorithm is proposed to detect the number of tags in a collided slot.Mean shift algorithm is utilized,and some properties of backscatter signals are investigated.Simulation results verify the effectiveness of the proposed solution in terms of low estimation error with a high SNR range,outperforming the existing MAC layer approaches.
基金supported by Innovation Research Group of Universities in Chongqing(CXQT21030)Chongqing Talents:Exceptional Young Talents Project(CQYC201905100)Chongqing Youth Expert Studio,Hong Kong Scholars Program。
文摘Grain growth directly influences the plasticity and strength of Mg alloys.As the grain size decreases from the microscale to the nanoscale,the plasticity of Mg alloys continually increases,whereas the strength first increases and later decreases.These trends are observed because the plastic deformation mechanism changes from dislocation–twinning dominance to grain boundary dominance.In this study,the factors influencing grain growth,such as the temperature of plastic deformation/annealing,second-phase particles and solute atoms,are examined to aid effective control of the grain size.Additionally,the mechanisms of grain growth,typically induced by strain and thermal activation,are clarified.Strain-induced grain boundary migration is attributable to the difference in the strain energy stored in adjacent grains with high-density dislocations.Heat-induced grain boundary migration is driven by the difference in the energy of the grain boundary/subgrain boundary and boundary curvature.Abnormal grain growth can be induced by anisotropy of the strain energy,anisotropy of the grain boundary mobility,depinning of the second phase and high misorientation gradient.
文摘Recently,object identification with radio frequency identification(RFID)technology is becoming increasingly popular.Identification time is a key performance metric to evaluate the RFID system.The present paper analyzes the deficiencies of the state-of-the-arts algorithms and proposes a novel sub-frame-based algorithm with adaptive frame breaking policy to lower the tag identification time for EPC global C1 Gen2 UHF RFID standard.Through the observation of slot statistics in a sub-frame,the reader estimates the tag quantity and efficiently calculates an optimal frame size to fit the unread tags.Only when the expected average identification time in the calculated frame size is less than that in the previous frame size,the reader starts the new frame.Moreover,the estimation of the proposed algorithm is implemented by the look-up tables,which allows dramatically reduction in the computational complexity.Simulation results show noticeable throughput and time efficiency improvements of the proposed solution over the existing approaches.
基金supported by the National Natural Science Foundation of China(52171288,51890914)the Key Research and Development Program of Shandong Province(Major Innovation Project)(2022CXGC020405)+3 种基金the National Ministry of Industry and Information Technology Innovation Special Project-Engineering Demonstration Application of Subsea Oil and Gas Production System-Subject 4“Research on Subsea Christmas Tree and Wellhead Offshore Testing Technology”[MC-201901-S01-04]the Fundamental Research Funds for the Central Universities(20CX02410A)the Development Fund of Shandong Key Laboratory of Oil&Gas Storage and Transportation SafetyCNPq,CAPES and FAPERJ of Brazil。
文摘The nonlinear dynamic behaviors of viscoelastic axially functionally graded material(AFG)pipes conveying pulsating internal flow are very complex.And the dynamic behavior will induce the failure of the pipes,and research of vibration and stability of pipes becomes a major concern.Considering that the elastic modulus,density,and coefficient of viscoelastic damping of the pipe material vary along the axial direction,the transverse vibration equation of the viscoelastic AFG pipe conveying pulsating fluid is established based on the Euler-Bernoulli beam theory.The generalized integral transform technique(GITT)is used to transform the governing fourth-order partial differential equation into a nonlinear system of fourth-order ordinary differential equations in time.The time domain diagram,phase portraits,Poincarémap and power spectra diagram at different dimensionless pulsation frequencies,are discussed in detail,showing the characteristics of chaotic,periodic,and quasi-periodic motion.The results show that the distributions of the elastic modulus,density,and coefficient of viscoelastic damping have significant effects on the nonlinear dynamic behavior of the viscoelastic AFG pipes.With the increase of the material property coefficient k,the transition between chaotic,periodic,and quasi-periodic motion occurs,especially in the high-frequency region of the flow pulsation.
基金supported by the National Key Research and Development Program of China(Grant No.2017YFB1104500)the National Natural Science Foundation of China(Grant No.61775240)the Foundation for the Author of National Excellent Doctoral Dissertation of China(Grant No.201432)。
文摘We investigate how the splicing mode of a holographic element(hogel)affects the reconstruction of a 3 D scene to improve the reconstruction resolution of a holographic stereogram fabricated using the effective perspective image segmentation and mosaicking method(EPISM).First,the effect of hogel spatial multiplexing on holographic recording and reconstruction is studied based on the mechanism of recording interference fringes in the holographic recording medium.Second,combined with the influence of multiple exposures on the hologram's diffraction efficiency,the diffraction efficiency of the holographic stereogram is analyzed in the spatial multiplexing mode.The holographic stereogram is then regarded as a special optical imaging system.The theory of spatial bandwidth product is adopted to describe the comprehensive resolution of the holographic stereogram,which explains why hogel spatial multiplexing can significantly improve the reconstruction resolution of a holographic stereogram.Compared with the traditional printing method under the same parameters in optical experiments,hogel spatial multiplexing has a lower diffraction efficiency but a higher quality of reconstructed image,consistent with the theoretical analysis.
基金The authors received funding for this study from the National Key R&D Program(https://chinainnovationfunding.eu/national-key-rd-programmes/),project contract No.2018YFB1802102(G.W.)and 2018AAA0103203(W.T,F.X,G.W.)from the National Natural Science Foundation of China(https://www.nsfc.gov.cn/),project contracts No.61971113(G.W.)and 61901095(D.I.)+6 种基金from the Guangdong Provincial Research and Development Plan in Key Areas(https://chinainnovationfunding.eu/funding-programmes-guangdong-province-2/)project contracts No.2019B010141001(G.W.)and 2019B010142001(G.W.)from the Sichuan Provincial Science and Technology Planning Program(https://www.sc.gov.cn/10462/10758/10759/10763/2010/10/28/10147629.shtml)project contracts No.2020YFG0039(G.W.),2021YFG0013(G.W.),and 2021YFH0133(D.I.)from the Ministry of Education(http://en.moe.gov.cn/)and China Mobile(http://www.chinamobileltd.com)Joint Fund Program,project contract No.MCM20180104(G.W.,G.L.)from the fundamental research funds for the Central Universities(managed by Department of Finance,https://www.fmprc.gov.cn/mfa_eng/wjb_663304/zzjg_663340/cws_665320/)project contract no.YGX2019Z022(G.W.,G.L.,D.I.).
文摘In this paper,a dynamic multi-ary query tree(DMQT)anti-collision protocol for Radio Frequency Identification(RFID)systems is proposed for large scale passive RFID tag identification.The proposed DMQT protocol is based on an iterative process between the reader and tags which identifies the position of collision bits through map commands and dynamically encodes them to optimize slots allocation through query commands.In this way,the DMQT completely eliminates empty slots and greatly reduces collision slots,which in turn reduces the identification time and energy costs.In addition and differently to other known protocols,the DMQT does not need to estimate the number of tags,reducing the protocol implementation complexity and eliminating the uncertainty caused by the estimation algorithm.A numerical analysis shows that DMQT has better performance than other algorithms for a number of tags larger than 300.Meanwhile,when the number of tags is 2000 and the tag identity(ID)length is 128 bits,the total identification time is 2.58 s and the average energy cost for a tag identification is 1.2 mJ,which are 16.9%and 10.4%less than those of state-of-the-art algorithms,respectively.In addition,a DMQT extension based on ACK command has also been presented to deal with capture effect and avoid missing identification.
基金This paper is supported by the National Youth Natural Science Foundation of China(61802208)the National Natural Science Foundation of China(61873131)+5 种基金the Natural Science Foundation of Anhui(1908085MF207 and 1908085QE217)the Key Research Project of Anhui Natural Science(KJ2020A1215 and KJ2020A1216)the Excellent Youth Talent Support Foundation of Anhui(gxyqZD2019097)the Postdoctoral Foundation of Jiangsu(2018K009B)the Higher Education Quality Project of Anhui(2019sjjd81,2018mooc059,2018kfk009,2018sxzx38 and 2018FXJT02)the Fuyang Normal University Doctoral Startup Foundation(2017KYQD0008).
文摘Brain tumor is one of the most common tumors with high mortality.Early detection is of great significance for the treatment and rehabilitation of patients.The single channel convolution layer and pool layer of traditional convolutional neural network(CNN)structure can only accept limited local context information.And most of the current methods only focus on the classification of benign and malignant brain tumors,multi classification of brain tumors is not common.In response to these shortcomings,considering that convolution kernels of different sizes can extract more comprehensive features,we put forward the multi-size convolutional kernel module.And considering that the combination of average-pooling with max-pooling can realize the complementary of the high-dimensional information extracted by the two structures,we proposed the dual-channel pooling layer.Combining the two structures with ResNet50,we proposed an improved ResNet50 CNN for the applications in multi-category brain tumor classification.We used data enhancement before training to avoid model over fitting and used five-fold cross-validation in experiments.Finally,the experimental results show that the network proposed in this paper can effectively classify healthy brain,meningioma,diffuse astrocytoma,anaplastic oligodendroglioma and glioblastoma.
基金Supported by the Beijing Key Specialists in Major Epidemic Prevention and Control,the Beijing Municipal Science&Technology Commission(Z201100005520028)the Financial Budgeting Project of Beijing Institute of Respiratory Medicine(Ysbz2023002)the National Natural Science Foundation of China(82204150).
文摘What is already known on this topic?Smoking is the primary risk factor for a poor prognosis in chronic respiratory disease(CRD).Current tobacco surveillance efforts in China focus on the general population and do not adequately cover CRD patients.What is added by this report?We employed electronic medical records(EMR)to track smoking habits in 28,334 hospitalized CRD patients at Beijing Chao-Yang Hospital.The rates of former and current smokers were 30.7%and 18.0%,respectively.Both former and current smokers exhibited an increased risk of respiratory symptoms and extended hospital stays.What are the implications for public health practice?These results underscore the importance of implementing smoking monitoring and targeted cessation interventions for hospitalized patients with CRDs.
基金supported by grants from the Foundation of Guangdong Science and Technology Department(Grant No.2010B031600158,XN Yang)Key Lab System Project of Guangdong Science and Technology Department(Grant No.2012A061400006,YL WU)
文摘Background: Available study revealed advanced tumors have a higher expression rate of MAGE-A3 gene which has a lot of single nucleotide polymorphism(SNP) loci with polymorphisms. This study aimed to analyze the allele frequency of SNP loci in MAGE-A3 gene and investigate the relationship between MAGE-A3 gene polymorphisms and clinical factors.Methods: Tumor samples of a cohort of 191 NSCLC patients were collected. EGFR m RNA expression were detected by q RT-PCR. SNPs in whole length of MAGE-A3 gene were detected by direct sequencing. Frequencies of the SNPs were correlated to gene expression, mutation status of EGFR and clinical factors.Results: Sequencing analysis confirmed that allele frequencies of genotypes on SNP loci rs5970360, rs5925210, rs5970361, rs5925211 and rs35123853 were CC(0.681)/CT(0.319), CC(0.660)/CG(0.340), CC(0.681)/CA(0.319), AA(0.984)/AT(0.016) and GG(1.000)/GA(0.000), respectively, which were different from the frequencies and genotypes of MAGE-A3 in SNP database. Chi-square tests showed the EGFR mR NA expression level had significant correlation with the genotypes of SNP loci rs5970360 and rs5925210. But all frequencies of each MAGE-A3 SNPs were not found significantly different between EGFR mutant and wild type patients. MAGE-A3 gene polymorphisms had no significant effects on survival of NSCLC patients.Conclusions: Chinese patients with NSCLC had different SNP patterns of MAGE-A3 in comparison with those in international SNP database. These MAGE-A3 SNP loci might have not prognostic significance. MAGE-A3 SNP loci rs5970360 and rs5925210 might be predictive for EGFR m RNA expression levels and helpful to the selection of patients for epidermal growth factor receptor(EGFR) targeted immunotherapy.
基金Project supported by the National Basic Research Program of China (Grant No.2015CB921403)the National Key Research and Development Program of China (Grant No.2016YFA0300804)+2 种基金the National Natural Science Foundation of China (Grant Nos.51871236,11874408,51431009,92263202,and 51971240)the Science Center of the National Science Foundation of China (Grant No.52088101)the Strategic Priority Research Program (B,Grant No.XDB33030200)of the Chinese Academy of Sciences (CAS)。
文摘Magnetic skyrmions in multilayer structures are considered as a new direction for the next generation of storage due to their small size,strong anti-interference ability,high current-driven mobility,and compatibility with existing spintronic technology.In this work,we present a tunable room temperature skyrmion platform based on multilayer stacks of MgO/FeNiB/Mo.We systematically studied the creation of magnetic skyrmions in MgO/FeNiB/Mo multilayer structures with perpendicular magnetic anisotropy(PMA).In these structures,the magnetic anisotropy changes from PMA to in-plane magnetic anisotropy(IMA)as the thickness of FeNiB layer increases.By adjusting the applied magnetic field and electric current,stable and high-density skyrmions can be obtained in the material system.The discovery of this material broadens the exploration of new materials for skyrmion and promotes the development of spintronic devices based on skyrmions.
基金the National Natural Science Foundation of China(Grant No.62206030)the Natural Science Foundation of Jiangsu(Grant Nos.BK20220624 and BK20220620)+2 种基金the Scientific Research Foundation of Jiangsu Provincial Education Department(Grant No.21KJB510010)the Changzhou Sci&Tech Program(Grant No.CJ20220085)the Leading Innovative Talents Introduction and Cultivation Project of Changzhou(Grant No.CQ20210084)。
文摘We fabricated monolayer n-type two-dimensional crystalline semiconducting films with millimeter-sized areas and remarkable morphological uniformity using an antisolvent-confined spin-coating method.The antisolvent can cause a downstream Marangoni flow,which improves the film morphologies.The deposited crystalline monolayer films exhibit excellent thermal stabilities after annealing,which reveals the annealing-induced enhancement of crystallinity.The transistors based on the n-type monolayer crystalline films show linear output characteristics and superior electron mobilities.The improved charge injection between monolayer films and Au electrodes results from the energy level shift as the films decrease to the monolayer,which leads to a lower injection barrier.This work demonstrates a promising method for fabricating air-stable,low-cost,high-performance,and large-area organic electronics.
基金Sponsored by the National Natural Science Foundation of China(Grant No.51178078)the 863 Project of the Ministry of Science and Technology of the People's Republic of China(Grant No.2007AA11Z133)+1 种基金the Natural Science Foundation of Science Department of Liaoning Province(Grant No.2020⁃BS⁃215)the Scientific Research Program of Education Department of Liaoning Province(Grant No.LJKZ0721).
文摘SRUHSC⁃RC(Steel Reinforced Ultra High Strength Concrete⁃Reinforced Concrete)structures are used extensively in super high⁃rise buildings.However,it has obvious brittleness.Wrapping structural steel inside is a good way to alleviate the brittleness problem.The purpose of this study is to investigate seismic behavior of SRUHSC⁃RC exterior joints on the basis of experimental results of eleven specimens under the reversed cyclic loading.The relationship among the force⁃displacement curve,ductility,energy dissipation property,strength degradation,stiffness degradation,the strains of steel bone and stirrup at the core area of the joint were analyzed based on the test results.It is shown that axial compression ratio and stirrup volumetric ratio have significant effects on the shear behavior of SRUHSC⁃RC frame exterior joints.The general requirement on the axial⁃load level and the amount of confinement stirrup for the joints in the design is suggested.
基金the National Science Foundation for Young Scientists of China(No.81602919)the National Science Foundation for Young Scientists of China(No.82070814)+1 种基金the Suzhou Science and Technology Development Plan(No.SYS2018099)and the 5th Suzhou Health Talent Program(No.GSWS2019071).
文摘BACKGROUND Type 1 diabetes(T1D)is a severe and prevalent metabolic disease.Due to its high heredity,an increasing number of genome-wide association studies have been performed,most of which were from hospital-based case-control studies with a relatively small sample size.The association of single nucleotide polymorphisms(SNPs)and T1D has been less studied and is less understood in natural cohorts.AIM To investigate the significant variants of T1D,which could be potential biomarkers for T1D prediction or even therapy.METHODS A genome-wide association study(GWAS)of adult T1D was performed in a nested case-control study(785 cases vs 804 controls)from a larger 5-year cohort study in Suzhou,China.Potential harmful or protective SNPs were evaluated for T1D.Subsequent expression and splicing quantitative trait loci(eQTL and sQTL)analyses were carried out to identify target genes modulated by these SNPs.RESULTS A harmful SNP for T1D,rs3117017[odds ratio(OR)=3.202,95%confidence interval(CI):2.296-4.466,P=9.33×10-4]and three protective SNPs rs55846421(0.113,0.081-0.156,1.76×10-9),rs75836320(0.283,0.205-0.392,1.07×10-4),rs362071(0.568,0.495-0.651,1.66×10-4)were identified.Twenty-two genes were further identified as potential candidates for T1D onset.CONCLUSION We identified a potential genetic basis of T1D,both protective and harmful,using a GWAS in a larger nested case-control study of a Chinese population.
文摘This paper uses the ARMA model method to fit the data of the urban and the rural residents’ per capita income in China and builds the MA(2) and AR(2) model. With the model, this paper predicts their trends in 5 years, also uses the prediction to analyze the income gap. The results show that in the next 5 years, the rural and the urban residents’ per capita income will be increasing steadily, but the level remains very low, the income gap is still large.
文摘In this paper, the boundary layer equations (abbreviation BLE) for exterior flow around an obstacle are established using semi-geodesic coordinate system (S-coordinate) based on the curved two dimensional surface of the obstacle. BLE are nonlinear partial differential equations on unknown normal viscous stress tensor and pressure on the obstacle and the existence of solution of BLE is proved. In addition a dimensional split method for dimensional three Navier-Stokes equations is established by applying several 2D-3C partial differential equations on two dimensional manifolds to approach 3D Navier-Stokes equations. The examples for the exterior flow around spheroid and ellipsoid are presents here.
基金Supported by National Natural Science Foundation of China(NSFC)(No.81260620)Zhuang Yao Medicines Collaborative Innovation Center[Gui JKY(2013)No.20]+2 种基金Guangxi Zhuang Yao Medicines Key Laboratory[Gui KJZ(2014)No.32]Guangxi Key Disciplines on Zhuang Medicine[Gui JKY(2013)No.16]Studies of Bagui Scholars on Innovation Theory and Efficacy of TCM
文摘[Objectives]To establish HPLC finger-print of Marchantia convolute Gao et Chang,and to control the quality of medicinal materials. [Methods] Agilent ZORBAX SB-C18 chromatographic column( 4. 6 mm × 250 mm,5μm) was adopted,acetonitrile( B)-0. 1% phosphoric solution( D) was used as the mobile phase( gradient elution),and the detection was conducted at the wavelength of 230 nm and at the column temperature of 25℃. HPLC finger-print of herb materials in the upland-field was established,and 8 lots of medicinal materials were used for the similarity assessment to establish the finger-print. [Results] Theprecision,repeatability and stability RSD of HPLC finger-prints of the 8 lots of Marchantia convoluta Gao et Chang were all less than 3%,and their similarities were all greater than 0. 75; 6 common peaks were observed,and the control finger-print was also established. [Conclusions] With reliable data and simple and efficient manipulations,HPLC finger-print analysis can provide references for the quality assessment of Marchantia convoluta Gao et Chang.
基金the National Natural Science Foundation of China(Nos.51802259and 51772243)China Postdoctoral Science Foundation Funded Project(No.2019M663785)+4 种基金the Natural Science Foundation of Shaanxi(No.2019JQ-510)Xi’an and Xi’an Beilin District Programs for Science and Technology Plan(Nos.201805037YD15CG21(18)and GX1913)the Promotion Program for Youth of Shaanxi University Science and Technology Association(No.20190415)Fund of Key laboratory of Processing and Quality Evaluation Technology of Green Plastics of China National Light Industry Council(No.PQETGP2019003)the Ph.D.Start-up Fund Project(No.108-451118001)of Xi’an University of Technology。
文摘With the development of nanobiotechnology,the carbon nanotubes(CNTs)and protein hybrids system has attracted an increasing attention for great potential application in nanotechnology,medicine,smart materials,light industry,and biology.In this review,the main preparation processes,impact factors,measurement of interactions and potential applications of CNTs/protein are presented from the aspect of experiments.Meanwhile,the proper forces detection methods are illustrated comprehensively to complete the quantitative measurement.Atomic force microscope(AFM)and surface force apparatus(SFA)experiments are described in detail to confirm the powerful function in measuring the interaction forces.In addition,the impact of different protein structures(amino acid residues,αHelix,polypeptide chain,and assembled subunits)on interactions between CNTs and protein is presented and different amino acid residues may intervene largely on interactions.Owing to the relatively little knowledge about the structure,function,and spatial orientation of proteins interaction with CNTs surface,we assume that the key problem is how to prepare CNTs and protein specimen with unique structure(such as the variation of secondary and tridimensional structure of protein or the single CNTs)to investigate the interaction forces instead of the designed,preparation,and detection methods.
文摘The laparoendoscopic single-site (LESS) technique is the latest technical innovation in laparoscopic surgery to undergo exponential development in urology. This study undertaken to illustrate our initial experience LESS radical prostatectomy (RP) and analyze early outcomes. Nineteen patients diagnosed with prostate cancer underwent LESS-RP in our institute. The patients were divided into two groups: conventional LESS and transurethral assistant LESS. Preoperative, perioperative, postoperative, pathologic, and functional outcomes data were assessed. With the help of a transurethral assistant, the mean operation and anastomosis time were decreased markedly. No focal positive margins were encountered. No prostate-specific antigen recurrence was detected 1 month postoperatively. Complete continence recovery (no pad) was observed in 32% of the patients at 1 month after the operation. No intraoperative and postoperative complications were reported, LESS-RP is a feasible and effective surgical procedure for treatment of prostate cancer. Moreover, transurethral assistant LESS could reduce the difficulty of LESS-RP and shorten the operation time.