Oxalidaceae is one of the most important plant families in horticulture,and its key commercially relevant genus,Averrhoa,has diverse growth habits and fruit types.Here,we describe the assembly of a high-quality chromo...Oxalidaceae is one of the most important plant families in horticulture,and its key commercially relevant genus,Averrhoa,has diverse growth habits and fruit types.Here,we describe the assembly of a high-quality chromosomescale genome sequence for Averrhoa carambola(star fruit).Ks distribution analysis showed that A.carambola underwent a whole-genome triplication event,i.e.,the gamma event shared by most eudicots.Comparisons between A.carambola and other angiosperms also permitted the generation of Oxalidaceae gene annotations.We identified unique gene families and analyzed gene family expansion and contraction.This analysis revealed significant changes in MADS-box gene family content,which might be related to the cauliflory of A.carambola.In addition,we identified and analyzed a total of 204 nucleotide-binding site,leucine-rich repeat receptor(NLR)genes and 58 WRKY genes in the genome,which may be related to the defense response.Our results provide insights into the origin,evolution and diversification of star fruit.展开更多
The Goos-H?nchen(GH) shift of graphene in the terahertz frequency range is investigated, and an extremely high GH shift is obtained owing to the excitation of surface plasmon resonance in graphene in the modified O...The Goos-H?nchen(GH) shift of graphene in the terahertz frequency range is investigated, and an extremely high GH shift is obtained owing to the excitation of surface plasmon resonance in graphene in the modified Otto configuration.It is shown that the GH shift can be positive or negative, and can be enhanced by introducing a nonlinearity in the substrate.Large and bistable GH shifts are demonstrated to be due to the hysteretic behavior of the reflectance phase. The bistable GH shift can be manipulated by changing the thickness of the air gap and the Fermi level or relaxation time of graphene.展开更多
This paper classifies the scenario elements which affect the real-time information needs of mobile commerce users, and proposes a nomination model that integrates the user’s personalized context elements. In this mod...This paper classifies the scenario elements which affect the real-time information needs of mobile commerce users, and proposes a nomination model that integrates the user’s personalized context elements. In this model, the top K scenarios that have the greatest impact on each user’s instant information demands are calculated from the user’s current scenario and historical data, thereby constructing a user personalized situation and improving it as an input condition that existing scenario-based multi-dimensional information recommendation algorithm is used for project nomination. Result/Conclusion: The improved algorithm and other three algorithms were compared by Movie lens and MBook Crossing dataset. The experimental results show that the model has higher prediction accuracy and can effectively improve user satisfaction and more effectively and solve personalized nomination issues in a mobile commerce environment.展开更多
Background:Lung cancer is the most commonly diagnosed cancer worldwide.Its survival rate can be significantly improved by early screening.Biomarkers based on radiomics features have been found to provide important phy...Background:Lung cancer is the most commonly diagnosed cancer worldwide.Its survival rate can be significantly improved by early screening.Biomarkers based on radiomics features have been found to provide important physiological information on tumors and considered as having the potential to be used in the early screening of lung cancer.In this study,we aim to establish a radiomics model and develop a tool to improve the discrimination between benign and malignant pulmonary nodules.Methods:A retrospective study was conducted on 875 patients with benign or malignant pulmonary nodules who underwent computed tomography(CT)examinations between June 2013 and June 2018.We assigned 612 patients to a training cohort and 263 patients to a validation cohort.Radiomics features were extracted from the CT images of each patient.Least absolute shrinkage and selection operator(LASSO)was used for radiomics feature selection and radiomics score calculation.Multivariate logistic regression analysis was used to develop a classification model and radiomics nomogram.Radiomics score and clinical variables were used to distinguish benign and malignant pulmonary nodules in logistic model.The performance of the radiomics nomogram was evaluated by the area under the curve(AUC),calibration curve and Hosmer-Lemeshow test in both the training and validation cohorts.Results:A radiomics score was built and consisted of 20 features selected by LASSO from 1288 radiomics features in the training cohort.The multivariate logistic model and radiomics nomogram were constructed using the radiomics score and patients’age.Good discrimination of benign and malignant pulmonary nodules was obtained from the training cohort(AUC,0.836;95%confidence interval[CI]:0.793-0.879)and validation cohort(AUC,0.809;95%CI:0.745-0.872).The Hosmer-Lemeshow test also showed good performance for the logistic regression model in the training cohort(P=0.765)and validation cohort(P=0.064).Good alignment with the calibration curve indicated the good performance of the nomogram.Conclusions:The established radiomics nomogram is a noninvasive preoperative prediction tool for malignant pulmonary nodule diagnosis.Validation revealed that this nomogram exhibited excellent discrimination and calibration capacities,suggesting its clinical utility in the early screening of lung cancer.展开更多
In this paper, we have shown that perfect absorption at terahertz frequencies can be achieved by using a composite structure where graphene is coated on one-dimensional photonic crystal(1 DPC) separated by a dielectri...In this paper, we have shown that perfect absorption at terahertz frequencies can be achieved by using a composite structure where graphene is coated on one-dimensional photonic crystal(1 DPC) separated by a dielectric. Due to the excitation of optical Tamm states(OTSs) at the interface between the graphene and 1 DPC, a strong absorption phenomenon occurs induced by the coupling of the incident light and OTSs. Although the perfect absorption produced by a metal–distributed Bragg reflector structure has been researched extensively, it is generally at a fixed frequency and not tunable. Here, we show that the perfect absorption at terahertz frequency not only can be tuned to different frequencies but also exhibits a high absorption over a wide angle range. In addition,the absorption of the proposed structure is insensitive to the polarization, and multichannel absorption can berealized by controlling the thickness of the top layer.展开更多
An ultrasensitive biosensor based on hybrid structure and composed of long-range surface plasmon polariton(LRSPP) and dielectric planar waveguide(PWG) modes is proposed. Both PWG and LRSPP modes have strong resonances...An ultrasensitive biosensor based on hybrid structure and composed of long-range surface plasmon polariton(LRSPP) and dielectric planar waveguide(PWG) modes is proposed. Both PWG and LRSPP modes have strong resonances to form strong coupling between the two modes, and the two modes can couple to enhance sensitivity of sensors. In the hybrid structure, PWG is composed of cytop–Si–cytop multilayers and the LRSPP configuration is composed of cytop–metal–sensing medium multilayer slabs. The highest imaging sensitivities of 2264 and3619 RIU-1were realized in the proposed sensors based on Au and Al-monolayer graphene, respectively, which are nearly 1.2 and 1.9 times larger than the 1910 RIU-1sensitivity of the conventional LRSPR sensor(LRSPP sensor). Moreover, it is demonstrated that the PWG-coupled LRSPP biosensor is applicable to the sensing medium,with refractive index in the vicinity of 1.34.展开更多
As a kind of two-dimensional transition metal dichalcogenide material, tungsten diselenide(WSe_2) has attracted increasing attention, owing to its gapped electronic structure, relatively high carrier mobility, and val...As a kind of two-dimensional transition metal dichalcogenide material, tungsten diselenide(WSe_2) has attracted increasing attention, owing to its gapped electronic structure, relatively high carrier mobility, and valley pseudospin, all of which show its valuable nonlinear optical properties. There are few studies on the nonlinear optical properties of WSe_2 and correlation with its electronic structure. In this paper, the effects of spatial self-phase modulation(SSPM) and distortion influence of WSe_2 ethanol suspensions are systematically studied, namely,the nonlinear refractive index and third-order nonlinear optical effect. We obtained the WSe_2 dispersions SSPM distortion formation mechanism, and through it, we calculated the nonlinear refractive index n_2,nonlinear susceptibility χ^(3), and their wavelength dependence under the excitation of 457 nm, 532 nm, and671 nm lasers. Moreover, by use of its strong and broadband nonlinear optical response, all-optical switching of two different laser beams due to spatial cross-phase modulation has been realized experimentally. Our results are useful for future optical devices, such as all-optical switching and all-optical information conversion.展开更多
The photonic spin Hall effect(SHE) has been intensively studied and widely applied, especially in spin photonics.However, the SHE is weak and is difficult to detect directly. In this paper, we propose a method to enha...The photonic spin Hall effect(SHE) has been intensively studied and widely applied, especially in spin photonics.However, the SHE is weak and is difficult to detect directly. In this paper, we propose a method to enhance SHE with the guided-wave surface-plasmon resonance(SPR). By covering a dielectric with high refractive index on the surface of silver film, the photonic SHE can be greatly enhanced, and a giant transverse shift of horizontal polarization state is observed due to the evanescent field enhancement near the interface at the top dielectric layer and air. The maximum transverse shift of the horizontal polarization state with 11.5 μm is obtained when the thickness of Si film is optimum. There is at least an order of magnitude enhancement in contrast with the transverse shift in the conventional SPR configuration. Our research is important for providing an effective way to improve the photonic SHE and may offer the opportunity to characterize the parameters of the dielectric layer with the help of weak measurements and development of sensors based on the photonic SHE.展开更多
In this article,we investigate the phenomenon of coherent perfect absorption(CPA)with bulk Dirac semimetal(BDS)thin film.CPA of BDS appears at the frequency of 43.89 THz with 0°phase modulation of two coherent in...In this article,we investigate the phenomenon of coherent perfect absorption(CPA)with bulk Dirac semimetal(BDS)thin film.CPA of BDS appears at the frequency of 43.89 THz with 0°phase modulation of two coherent input lights.Meanwhile,it shows that CPA can be realized under oblique incidence circumstances for both TM and TE polarizations.Moreover,the frequency of CPA can be adjusted by altering the thickness of BDS thin film,and the dynamic regulation of CPA can be realized by changing the Fermi energy.Finally,the peak coherent absorption frequency can be controlled by changing the degeneracy factor.展开更多
The optical Tamm state(OTS), which exists generally at the interface between metal and a dielectric Bragg mirror, has been studied extensively in the visible and near infrared spectra. Nevertheless, OTS in the teraher...The optical Tamm state(OTS), which exists generally at the interface between metal and a dielectric Bragg mirror, has been studied extensively in the visible and near infrared spectra. Nevertheless, OTS in the terahertz(THz) region normally receives far less attention. In this Letter, we demonstrate the physical mechanism of OTS at the interface between graphene and a dielectric Bragg mirror in the THz frequency band by applying the transfer matrix method and dispersion characteristics. Based on such mechanisms, we propose an efficient method that can precisely generate and control OTS at a desired angle and frequency. Moreover, we show that the OTS is dependent on the optical conductivity of graphene, making the graphene–dielectric-Bragg-mirror a good candidate for dynamic tunable OTS device in the THz frequency range.展开更多
基金supported by The National Key Research and Development Program of China(ref.2019YFC1711103)the Fujian Agriculture and Forestry University Science and Technology Innovation Special Fund Project(ref.KFA17331A)+1 种基金the Natural Science Foundation of Fujian(ref.2019J01410)the Fujian Agriculture and Forestry University 2015 Outstanding Youth Fund Project(ref.xjq201620).
文摘Oxalidaceae is one of the most important plant families in horticulture,and its key commercially relevant genus,Averrhoa,has diverse growth habits and fruit types.Here,we describe the assembly of a high-quality chromosomescale genome sequence for Averrhoa carambola(star fruit).Ks distribution analysis showed that A.carambola underwent a whole-genome triplication event,i.e.,the gamma event shared by most eudicots.Comparisons between A.carambola and other angiosperms also permitted the generation of Oxalidaceae gene annotations.We identified unique gene families and analyzed gene family expansion and contraction.This analysis revealed significant changes in MADS-box gene family content,which might be related to the cauliflory of A.carambola.In addition,we identified and analyzed a total of 204 nucleotide-binding site,leucine-rich repeat receptor(NLR)genes and 58 WRKY genes in the genome,which may be related to the defense response.Our results provide insights into the origin,evolution and diversification of star fruit.
基金Project supported by the National Natural Science Foundation of China(Grant No.61505111).
文摘The Goos-H?nchen(GH) shift of graphene in the terahertz frequency range is investigated, and an extremely high GH shift is obtained owing to the excitation of surface plasmon resonance in graphene in the modified Otto configuration.It is shown that the GH shift can be positive or negative, and can be enhanced by introducing a nonlinearity in the substrate.Large and bistable GH shifts are demonstrated to be due to the hysteretic behavior of the reflectance phase. The bistable GH shift can be manipulated by changing the thickness of the air gap and the Fermi level or relaxation time of graphene.
文摘This paper classifies the scenario elements which affect the real-time information needs of mobile commerce users, and proposes a nomination model that integrates the user’s personalized context elements. In this model, the top K scenarios that have the greatest impact on each user’s instant information demands are calculated from the user’s current scenario and historical data, thereby constructing a user personalized situation and improving it as an input condition that existing scenario-based multi-dimensional information recommendation algorithm is used for project nomination. Result/Conclusion: The improved algorithm and other three algorithms were compared by Movie lens and MBook Crossing dataset. The experimental results show that the model has higher prediction accuracy and can effectively improve user satisfaction and more effectively and solve personalized nomination issues in a mobile commerce environment.
基金Key R&D project of Shandong Province,Grant/Award Number:2018GSF118152
文摘Background:Lung cancer is the most commonly diagnosed cancer worldwide.Its survival rate can be significantly improved by early screening.Biomarkers based on radiomics features have been found to provide important physiological information on tumors and considered as having the potential to be used in the early screening of lung cancer.In this study,we aim to establish a radiomics model and develop a tool to improve the discrimination between benign and malignant pulmonary nodules.Methods:A retrospective study was conducted on 875 patients with benign or malignant pulmonary nodules who underwent computed tomography(CT)examinations between June 2013 and June 2018.We assigned 612 patients to a training cohort and 263 patients to a validation cohort.Radiomics features were extracted from the CT images of each patient.Least absolute shrinkage and selection operator(LASSO)was used for radiomics feature selection and radiomics score calculation.Multivariate logistic regression analysis was used to develop a classification model and radiomics nomogram.Radiomics score and clinical variables were used to distinguish benign and malignant pulmonary nodules in logistic model.The performance of the radiomics nomogram was evaluated by the area under the curve(AUC),calibration curve and Hosmer-Lemeshow test in both the training and validation cohorts.Results:A radiomics score was built and consisted of 20 features selected by LASSO from 1288 radiomics features in the training cohort.The multivariate logistic model and radiomics nomogram were constructed using the radiomics score and patients’age.Good discrimination of benign and malignant pulmonary nodules was obtained from the training cohort(AUC,0.836;95%confidence interval[CI]:0.793-0.879)and validation cohort(AUC,0.809;95%CI:0.745-0.872).The Hosmer-Lemeshow test also showed good performance for the logistic regression model in the training cohort(P=0.765)and validation cohort(P=0.064).Good alignment with the calibration curve indicated the good performance of the nomogram.Conclusions:The established radiomics nomogram is a noninvasive preoperative prediction tool for malignant pulmonary nodule diagnosis.Validation revealed that this nomogram exhibited excellent discrimination and calibration capacities,suggesting its clinical utility in the early screening of lung cancer.
基金National Natural Science Foundation of China(NSFC)(51806001,61490713,61505111)Natural Science Foundation of Guangdong Province(2015A030313549)+3 种基金China Postdoctoral Science Foundation(2016M602509)Science and Technology Planning Project of Guangdong Province(2016B050501005)Science and Technology Project of Shenzhen(JCYJ20150324141711667)Natural Science Foundation of SZU(827-000051,827-000052,827-000059)
文摘In this paper, we have shown that perfect absorption at terahertz frequencies can be achieved by using a composite structure where graphene is coated on one-dimensional photonic crystal(1 DPC) separated by a dielectric. Due to the excitation of optical Tamm states(OTSs) at the interface between the graphene and 1 DPC, a strong absorption phenomenon occurs induced by the coupling of the incident light and OTSs. Although the perfect absorption produced by a metal–distributed Bragg reflector structure has been researched extensively, it is generally at a fixed frequency and not tunable. Here, we show that the perfect absorption at terahertz frequency not only can be tuned to different frequencies but also exhibits a high absorption over a wide angle range. In addition,the absorption of the proposed structure is insensitive to the polarization, and multichannel absorption can berealized by controlling the thickness of the top layer.
基金National Natural Science Foundation of China(NSFC)(61505111)Guandong Natural Science Foundation(2015A030313549)+2 种基金Science and Technology Planning Project of Guangdong Province(2016B050501005)Science and Technology Project of Shenzhen(JCYJ20140828163633996,JCYJ20150324141711667)Natural Science Foundation of SZU(201452,201517,827-000051,827-000052,827-000059)
文摘An ultrasensitive biosensor based on hybrid structure and composed of long-range surface plasmon polariton(LRSPP) and dielectric planar waveguide(PWG) modes is proposed. Both PWG and LRSPP modes have strong resonances to form strong coupling between the two modes, and the two modes can couple to enhance sensitivity of sensors. In the hybrid structure, PWG is composed of cytop–Si–cytop multilayers and the LRSPP configuration is composed of cytop–metal–sensing medium multilayer slabs. The highest imaging sensitivities of 2264 and3619 RIU-1were realized in the proposed sensors based on Au and Al-monolayer graphene, respectively, which are nearly 1.2 and 1.9 times larger than the 1910 RIU-1sensitivity of the conventional LRSPR sensor(LRSPP sensor). Moreover, it is demonstrated that the PWG-coupled LRSPP biosensor is applicable to the sensing medium,with refractive index in the vicinity of 1.34.
基金National Natural Science Foundation of China(NSFC)(11604216,61505111)China Postdoctoral Science Foundation(2017M622746,2018M633129)Natural Science Foundation of Guangdong Province(2018A030313198)
文摘As a kind of two-dimensional transition metal dichalcogenide material, tungsten diselenide(WSe_2) has attracted increasing attention, owing to its gapped electronic structure, relatively high carrier mobility, and valley pseudospin, all of which show its valuable nonlinear optical properties. There are few studies on the nonlinear optical properties of WSe_2 and correlation with its electronic structure. In this paper, the effects of spatial self-phase modulation(SSPM) and distortion influence of WSe_2 ethanol suspensions are systematically studied, namely,the nonlinear refractive index and third-order nonlinear optical effect. We obtained the WSe_2 dispersions SSPM distortion formation mechanism, and through it, we calculated the nonlinear refractive index n_2,nonlinear susceptibility χ^(3), and their wavelength dependence under the excitation of 457 nm, 532 nm, and671 nm lasers. Moreover, by use of its strong and broadband nonlinear optical response, all-optical switching of two different laser beams due to spatial cross-phase modulation has been realized experimentally. Our results are useful for future optical devices, such as all-optical switching and all-optical information conversion.
基金National Natural Science Foundation of China(NSFC)(61505111,61490713,51806001)Natural Science Foundation of Guangdong Province(2015A030313549)+3 种基金China Postdoctoral Science Foundation(2016M602509)Science and Technology Planning Project of Guangdong Province(2016B050501005)Science and Technology Project of Shenzhen(JCYJ20150324141711667)Natural Science Foundation of SZU(827-000051,827-000052,827-000059)
文摘The photonic spin Hall effect(SHE) has been intensively studied and widely applied, especially in spin photonics.However, the SHE is weak and is difficult to detect directly. In this paper, we propose a method to enhance SHE with the guided-wave surface-plasmon resonance(SPR). By covering a dielectric with high refractive index on the surface of silver film, the photonic SHE can be greatly enhanced, and a giant transverse shift of horizontal polarization state is observed due to the evanescent field enhancement near the interface at the top dielectric layer and air. The maximum transverse shift of the horizontal polarization state with 11.5 μm is obtained when the thickness of Si film is optimum. There is at least an order of magnitude enhancement in contrast with the transverse shift in the conventional SPR configuration. Our research is important for providing an effective way to improve the photonic SHE and may offer the opportunity to characterize the parameters of the dielectric layer with the help of weak measurements and development of sensors based on the photonic SHE.
基金supported by the National Natural Science Foundation of China(Nos.61875133 and 11874269)the Science and Technology Project of Shenzhen(Nos.JCYJ20190808143801672,JCYJ20190808150803580,JCYJ20180305125036005,JCYJ20180305124842330,and JCYJ20180305125443569)the Natural Science Foundation of Guangdong(No.2018A030313198)。
文摘In this article,we investigate the phenomenon of coherent perfect absorption(CPA)with bulk Dirac semimetal(BDS)thin film.CPA of BDS appears at the frequency of 43.89 THz with 0°phase modulation of two coherent input lights.Meanwhile,it shows that CPA can be realized under oblique incidence circumstances for both TM and TE polarizations.Moreover,the frequency of CPA can be adjusted by altering the thickness of BDS thin film,and the dynamic regulation of CPA can be realized by changing the Fermi energy.Finally,the peak coherent absorption frequency can be controlled by changing the degeneracy factor.
基金supported by the National Natural Science Foundation of China(Nos.11704119,61505111,61575127,and 61490713)the Natural Science Foundation of Hunan Province(No.2018JJ3325)+2 种基金the Natural Science Foundation of Guangdong Province(No.2015A030313549)the Science and Technology Planning Project of Guangdong Province(No.2016B050501005)the Scientific Research Fund of Hunan Provincial Education Department(No.17C0945)
文摘The optical Tamm state(OTS), which exists generally at the interface between metal and a dielectric Bragg mirror, has been studied extensively in the visible and near infrared spectra. Nevertheless, OTS in the terahertz(THz) region normally receives far less attention. In this Letter, we demonstrate the physical mechanism of OTS at the interface between graphene and a dielectric Bragg mirror in the THz frequency band by applying the transfer matrix method and dispersion characteristics. Based on such mechanisms, we propose an efficient method that can precisely generate and control OTS at a desired angle and frequency. Moreover, we show that the OTS is dependent on the optical conductivity of graphene, making the graphene–dielectric-Bragg-mirror a good candidate for dynamic tunable OTS device in the THz frequency range.