As Moore’s law deteriorates,the research and development of new materials system are crucial for transitioning into the post Moore era.Traditional semiconductor materials,such as silicon,have served as the cornerston...As Moore’s law deteriorates,the research and development of new materials system are crucial for transitioning into the post Moore era.Traditional semiconductor materials,such as silicon,have served as the cornerstone of modern technologies for over half a century.This has been due to extensive research and engineering on new techniques to continuously enrich silicon-based materials system and,subsequently,to develop better performed silicon-based devices.Meanwhile,in the emerging post Moore era,layered semiconductor materials,such as transition metal dichalcogenides(TMDs),have garnered considerable research interest due to their unique electronic and optoelectronic properties,which hold great promise for powering the new era of next generation electronics.As a result,techniques for engineering the properties of layered semiconductors have expanded the possibilities of layered semiconductor-based devices.However,there remain significant limitations in the synthesis and engineering of layered semiconductors,impeding the utilization of layered semiconductor-based devices for mass applications.As a practical alternative,heterogeneous integration between layered and traditional semiconductors provides valuable opportunities to combine the distinctive properties of layered semiconductors with well-developed traditional semiconductors materials system.Here,we provide an overview of the comparative coherence between layered and traditional semiconductors,starting with TMDs as the representation of layered semiconductors.We highlight the meaningful opportunities presented by the heterogeneous integration of layered semiconductors with traditional semiconductors,representing an optimal strategy poised to propel the emerging semiconductor research community and chip industry towards unprecedented advancements in the coming decades.展开更多
Many network presentation learning algorithms(NPLA)have originated from the process of the random walk between nodes in recent years.Despite these algorithms can obtain great embedding results,there may be also some l...Many network presentation learning algorithms(NPLA)have originated from the process of the random walk between nodes in recent years.Despite these algorithms can obtain great embedding results,there may be also some limitations.For instance,only the structural information of nodes is considered when these kinds of algorithms are constructed.Aiming at this issue,a label and community information-based network presentation learning algorithm(LC-NPLA)is proposed in this paper.First of all,by using the community information and the label information of nodes,the first-order neighbors of nodes are reconstructed.In the next,the random walk strategy is improved by integrating the degree information and label information of nodes.Then,the node sequence obtained from random walk sampling is transformed into the node representation vector by the Skip-Gram model.At last,the experimental results on ten real-world networks demonstrate that the proposed algorithm has great advantages in the label classification,network reconstruction and link prediction tasks,compared with three benchmark algorithms.展开更多
Pancreatic ductal adenocarcinoma(PDAC)is universally acknowledged as the cancer with the highest mortality rate.Berberine has high medicinal value and has been used as an anti-cancer agent.Hence the purpose of this st...Pancreatic ductal adenocarcinoma(PDAC)is universally acknowledged as the cancer with the highest mortality rate.Berberine has high medicinal value and has been used as an anti-cancer agent.Hence the purpose of this study was to investigate the anti-cancer effect of berberine in PDAC.Berberine was shown to have a selective anti-cancer effect on PDAC by MTT assay in vitro.Pancreatic cancer stem cells(PCSCs),regulated by epithelial-mesenchymal transition(EMT),could promote the proliferation of PDAC cells.However,berberine suppressed the proliferation and stemness of PCSCs through immunofluorescence staining,stem cell sphere assays and so forth in vitro.In vivo,berberine reduced tumor size and decreased the expression levels of Ki67,a marker of cellular proliferation,in orthotopic pancreatic tumors.In addition,berberine inhibited the EMT signaling pathway by RT-PCR and Western blotting methods both in vitro and in vivo.Our study indicates that berberine inhibits the proliferation of PDAC cells both in vivo and in vitro.The mechanism of the anti-cancer effect of berberine likely involves the inhibition of EMT.Therefore,berberine may be a novel antineoplastic drug with clinical efficacy in PDAC.展开更多
With the development of the Cyber-Physical Internet of Things System(CPIoTS),the number of Cyber-Physical System(CPS)applications accessed in networks has increased dramatically.Latency-sensitive resource orchestratio...With the development of the Cyber-Physical Internet of Things System(CPIoTS),the number of Cyber-Physical System(CPS)applications accessed in networks has increased dramatically.Latency-sensitive resource orchestration in CPS applications is extraordinarily essential for maintaining the Quality of Experience(QoE)for users.Although edge-cloud computing performs effectively in achieving latency-aware resource allocation in CPIoTS,existing methods fail to jointly consider the security and reliability requirements,thereby increasing the process latency of tasks and degrading the QoE of users.This paper aims to minimize the system latency of edge-cloud computing coupled with CPS while simultaneously considering the security and reliability requirements.We first consider a time-varying channel model as a Finite-State Markov Channel(FSMC)and propose a distributed blockchain-assisted CPIoTS to realize secure consensus and reliable resource orchestration by offloading computation tasks in edge-cloud computing.Moreover,we propose an efficient resource allocation algorithm,PPO-SRRA,that optimizes computing offloading and multi-dimension resource(e.g.,communication,computation,and consensus resource)allocation by using a policy-based Deep Reinforcement Learning(DRL)method.The experimental results show that the proposed resource allocation scheme can reduce the system latency and ensure consensus security.展开更多
Objective: The aim of this work was to evaluate anti-tumor effects of mDRA-6 plus nimesulide on a human hepatocellular cancer cell line, SMMC-7721, and study the main mechanisms. Methods: The DR5 receptor of SMMC-7721...Objective: The aim of this work was to evaluate anti-tumor effects of mDRA-6 plus nimesulide on a human hepatocellular cancer cell line, SMMC-7721, and study the main mechanisms. Methods: The DR5 receptor of SMMC-7721 cells was detected by flow cytometry (FCM). For further experimental application, SMMC-7721 cells were treated with proper dose of mDRA-6, nimesulide, or mDRA-6 plus 200 μmol/L nimesulide; untreated SMMC-7721 cells were comparably set as control. Cytotoxicity was tested by MTT assay; cell morphology was examined using Hoechst 33258 staining; and apoptosis was determined by FCM. Results: The positive rate of DR5 on SMMC-7721 was 95.0%. Either mDRA-6 or nimesulide alone induces SMMC-7721 cell death in a dose-dependent manner. Treatment of 1,600 ng/mL mDRA-6 for 12h led to a cell-death rate of 35.0%, while an increased cell-death rate (91.1%) was found under the same condition of mDRA-6 treatment supple- mented with 200 μmol/L nimesulide. Hoechst 33258 and Annexin V/PI staining confirmed apoptosis as the main cause of this anti-tumor response. Conclusion: Both mDRA-6 and nimesulide can induce apoptosis of SMMC-7721 cells, and they have synergistic anti-tumor activities against SMMC-7721.展开更多
Cognitive diagnosis is the judgment of the student’s cognitive ability, is a wide-spread concern in educational science. The cognitive diagnosis model (CDM) is an essential method to realize cognitive diagnosis measu...Cognitive diagnosis is the judgment of the student’s cognitive ability, is a wide-spread concern in educational science. The cognitive diagnosis model (CDM) is an essential method to realize cognitive diagnosis measurement. This paper presents new research on the cognitive diagnosis model and introduces four individual aspects of probability-based CDM and deep learning-based CDM. These four aspects are higher-order latent trait, polytomous responses, polytomous attributes, and multilevel latent traits. The paper also sorts on the contained ideas, model structures and respective characteristics, and provides direction for developing cognitive diagnosis in the future.展开更多
The effects of tourmaline on nitrogen removal performance and biofilm structures were comparatively investigated in two identical laboratory-scale sequencing batch biofilm reactors(SBBRs)(denoted SBBR1 and SBBR2) at d...The effects of tourmaline on nitrogen removal performance and biofilm structures were comparatively investigated in two identical laboratory-scale sequencing batch biofilm reactors(SBBRs)(denoted SBBR1 and SBBR2) at different nitrogen loading rates(NLRs) varying from(0.24 ± 0.01) to(1.26 ± 0.02) g N/(L·day). SBBR1 was operated in parallel with SBBR2, but SBBR1 was filled with polyurethane foam loaded tourmaline(TPU) carriers and another(SBBR2) filled with polyurethane foam(PU) carriers. Results obtained from this study showed that the excellent and stable performance of SBBR1 was obtained. Ammonia nitrogen removal and total nitrogen removal were higher in SBBR1 than that in SBBR2 with increase of NLR. At an NLR of(0.24 ± 0.01) g N/(L·day), the majority of the spherical and elliptical bacteria were surrounded by the extracellular polymeric substance(EPS) and bacillus or filamentous bacteria in two SBBRs biofilms. When NLR increased to(1.26 ± 0.02) g N/(L·day), the clusters were more obvious in the SBBR1 biofilm than that in the SBBR2 biofilm. Bacteria in SBBR1 were inclined to synthesis more EPS, and the formed EPS could protect the bacteria from free ammonia(FA) under extreme condition NLR(1.26 ± 0.02) g N/(L·day). The results of polymerase chain reaction-denaturing gradient gel electrophoresis analysis showed that the microbial community similarity in SBBR2 decreased more obviously than that in SBBR1 with the increase of NLR, which the microbial community in SBBR1 was relatively stable.展开更多
Recently,2-μm wave band has gained increasing interest due to its potential application for next-generation optical communication.But the development of 2-μm optical communications is substantially hampered by the m...Recently,2-μm wave band has gained increasing interest due to its potential application for next-generation optical communication.But the development of 2-μm optical communications is substantially hampered by the modulation speed due to the device bandwidth constraints.Thus,a high-speed modulator is highly demanded at 2μm.Motivated by this prospect,we demonstrate a high-speed silicon Mach–Zehnder modulator for a 2-μm wave band.The device is configured as a single-ended push–pull structure with waveguide electrorefraction via the free carrier plasma effect.The modulator was fabricated via a multiproject wafer shuttle run at a commercial silicon photonic foundry.The modulation efficiency of a single arm is measured to be 1.6 V·cm.The high-speed characterization is also performed,and the modulation speed can reach 80 Gbit/s with 4-level pulse amplitude modulation(PAM-4)formats.展开更多
This is the continuation of the paper”Central discontinuous Galerkin methods on overlapping cells with a non-oscillatory hierarchical reconstruction”by the same authors.The hierarchical reconstruction introduced the...This is the continuation of the paper”Central discontinuous Galerkin methods on overlapping cells with a non-oscillatory hierarchical reconstruction”by the same authors.The hierarchical reconstruction introduced therein is applied to central schemes on overlapping cells and to finite volume schemes on non-staggered grids.This takes a new finite volume approach for approximating non-smooth solutions.A critical step for high-order finite volume schemes is to reconstruct a non-oscillatory high degree polynomial approximation in each cell out of nearby cell averages.In the paper this procedure is accomplished in two steps:first to reconstruct a high degree polynomial in each cell by using e.g.,a central reconstruction,which is easy to do despite the fact that the reconstructed polynomial could be oscillatory;then to apply the hierarchical reconstruction to remove the spurious oscillations while maintaining the high resolution.All numerical computations for systems of conservation laws are performed without characteristic decomposition.In particular,we demonstrate that this new approach can generate essentially non-oscillatory solutions even for 5th-order schemes without characteristic decomposition.展开更多
On June 17 of 2016,a group of scientists from Chinese Academy of Fishery Sciences(CAFS)and Shenzhen BGI Fisheries Sci&Tech Co.Ltd.(BGI Fisheries)met together in Shenzhen,China to launch a novel project,the China A...On June 17 of 2016,a group of scientists from Chinese Academy of Fishery Sciences(CAFS)and Shenzhen BGI Fisheries Sci&Tech Co.Ltd.(BGI Fisheries)met together in Shenzhen,China to launch a novel project,the China Aquatic 10-100-1,000 Genomics Program,to conduct molecular breeding of^10 aquaculture species and sequence genomes of^100 and transcriptomes of^1,000 aquatic species.The main objective of this project is to build展开更多
Aggregation equations are broadly used tomodel population dynamicswith nonlocal interactions,characterized by a potential in the equation.This paper considers the inverse problem of identifying the potential from a si...Aggregation equations are broadly used tomodel population dynamicswith nonlocal interactions,characterized by a potential in the equation.This paper considers the inverse problem of identifying the potential from a single noisy spatialtemporal process.The identification is challenging in the presence of noise due to the instability of numerical differentiation.We propose a robust model-based technique to identify the potential by minimizing a regularized data fidelity term,and regularization is taken as the total variation and the squared Laplacian.A split Bregman method is used to solve the regularized optimization problem.Our method is robust to noise by utilizing a Successively Denoised Differentiation technique.We consider additional constraints such as compact support and symmetry constraints to enhance the performance further.We also apply thismethod to identify time-varying potentials and identify the interaction kernel in an agent-based system.Various numerical examples in one and two dimensions are included to verify the effectiveness and robustness of the proposed method.展开更多
To enhance the fruity flavour of pear wine by coculturing Saccharomyces yeasts with non-Saccharomyces,the coculture patterns were optimised based on the effect of different strains on the physicochemical properties an...To enhance the fruity flavour of pear wine by coculturing Saccharomyces yeasts with non-Saccharomyces,the coculture patterns were optimised based on the effect of different strains on the physicochemical properties and metabolites,and the interaction relationship in the coculture fermentation was also studied.These results showed that total volatiles of S.bayanus were higher than those of S.cerevisiae,especially esters,acids and phenols.The contents of total volatiles and esters were enhanced by sequential inoculation.The effect of coculturing S.bayanus Y4 with T.delbrueckii Y7 or Pichia sp.was better than that of coculturing with them with S.cerevisiae Y1,enhancing the contents of phenylethanol,acetate and ethyl esters.Furthermore,the esters(mainly ethyl esters)content was increased by 53.30%,and the acids content was decreased by 32.82%when S.bayanus Y4 was cocultured with T.delbrueckii Y7 by sequential inoculation compared with S.bayanus Y4 single inoculation.Their coculture increased theα-diversity of the fungal community and changed the correlation network between the microbiota.Redundancy analysis showed that Torulaspora was closely correlated to ethyl hexanoate,ethyl decanoate and ethyl 9-decenoate,while Saccharomyces was associated with hexanoic acid and octanoic acid.PICRUSt2 prediction revealed that Torulaspora may utilize the fatty acids produced by Saccharomyces to synthesize fatty acid ethyl esters.展开更多
Polyether-ether-ketone(PEEK)is believed to be the next-generation biomedical material for orthopaedic implants that may replace metal materials because of its good biocompatibility,appropriate mechanical properties an...Polyether-ether-ketone(PEEK)is believed to be the next-generation biomedical material for orthopaedic implants that may replace metal materials because of its good biocompatibility,appropriate mechanical properties and radiolucency.Currently,some PEEK implants have been used successfully for many years.However,there is no customised PEEK orthopaedic implant made by additive manufacturing licensed for the market,although clinical trials have been increasingly reported.In this review article,design criteria,including geometric matching,functional restoration,strength safety,early fixation,long-term stability and manufacturing capability,are summarised,focusing on the clinical requirements.An integrated framework of design and manufacturing processes to create customised PEEK implants is presented,and several typical clinical applications such as cranioplasty patches,rib prostheses,mandibular prostheses,scapula prostheses and femoral prostheses are described.The main technical challenge faced by PEEK orthopaedic implants lies in the poor bonding with bone and soft tissue due to its biological inertness,which may be solved by adding bioactive fillers and manufacturing porous architecture.The lack of technical standards is also one of the major factors preventing additive-manufactured customised PEEK orthopaedic implants from clinical translation,and it is good to see that the abundance of standards in the field of additive-manufactured medical devices is helping them enter the clinical market.展开更多
基金supported by National Key R&D Program of China(2020YFB2008704)the National Natural Science Foundation of China(62004114 and 62174098)+1 种基金Beijing Municipal Science and Technology Commission(Z221100005822011)The Tsinghua-Foshan Innovation Special Fund(2021THFS0215)。
文摘As Moore’s law deteriorates,the research and development of new materials system are crucial for transitioning into the post Moore era.Traditional semiconductor materials,such as silicon,have served as the cornerstone of modern technologies for over half a century.This has been due to extensive research and engineering on new techniques to continuously enrich silicon-based materials system and,subsequently,to develop better performed silicon-based devices.Meanwhile,in the emerging post Moore era,layered semiconductor materials,such as transition metal dichalcogenides(TMDs),have garnered considerable research interest due to their unique electronic and optoelectronic properties,which hold great promise for powering the new era of next generation electronics.As a result,techniques for engineering the properties of layered semiconductors have expanded the possibilities of layered semiconductor-based devices.However,there remain significant limitations in the synthesis and engineering of layered semiconductors,impeding the utilization of layered semiconductor-based devices for mass applications.As a practical alternative,heterogeneous integration between layered and traditional semiconductors provides valuable opportunities to combine the distinctive properties of layered semiconductors with well-developed traditional semiconductors materials system.Here,we provide an overview of the comparative coherence between layered and traditional semiconductors,starting with TMDs as the representation of layered semiconductors.We highlight the meaningful opportunities presented by the heterogeneous integration of layered semiconductors with traditional semiconductors,representing an optimal strategy poised to propel the emerging semiconductor research community and chip industry towards unprecedented advancements in the coming decades.
基金What is more,we thank the National Natural Science Foundation of China(Nos.61966039,62241604)the Scientific Research Fund Project of the Education Department of Yunnan Province(No.2023Y0565)Also,this work was supported in part by the Xingdian Talent Support Program for Young Talents(No.XDYC-QNRC-2022-0518).
文摘Many network presentation learning algorithms(NPLA)have originated from the process of the random walk between nodes in recent years.Despite these algorithms can obtain great embedding results,there may be also some limitations.For instance,only the structural information of nodes is considered when these kinds of algorithms are constructed.Aiming at this issue,a label and community information-based network presentation learning algorithm(LC-NPLA)is proposed in this paper.First of all,by using the community information and the label information of nodes,the first-order neighbors of nodes are reconstructed.In the next,the random walk strategy is improved by integrating the degree information and label information of nodes.Then,the node sequence obtained from random walk sampling is transformed into the node representation vector by the Skip-Gram model.At last,the experimental results on ten real-world networks demonstrate that the proposed algorithm has great advantages in the label classification,network reconstruction and link prediction tasks,compared with three benchmark algorithms.
基金This research was supported by 81803024(National Natural Science Foundation of China)and DUT21LK23(Fundamental Research Funds for the Central Universities).
文摘Pancreatic ductal adenocarcinoma(PDAC)is universally acknowledged as the cancer with the highest mortality rate.Berberine has high medicinal value and has been used as an anti-cancer agent.Hence the purpose of this study was to investigate the anti-cancer effect of berberine in PDAC.Berberine was shown to have a selective anti-cancer effect on PDAC by MTT assay in vitro.Pancreatic cancer stem cells(PCSCs),regulated by epithelial-mesenchymal transition(EMT),could promote the proliferation of PDAC cells.However,berberine suppressed the proliferation and stemness of PCSCs through immunofluorescence staining,stem cell sphere assays and so forth in vitro.In vivo,berberine reduced tumor size and decreased the expression levels of Ki67,a marker of cellular proliferation,in orthotopic pancreatic tumors.In addition,berberine inhibited the EMT signaling pathway by RT-PCR and Western blotting methods both in vitro and in vivo.Our study indicates that berberine inhibits the proliferation of PDAC cells both in vivo and in vitro.The mechanism of the anti-cancer effect of berberine likely involves the inhibition of EMT.Therefore,berberine may be a novel antineoplastic drug with clinical efficacy in PDAC.
基金This work has been supported by the National Natural Science Foundation of China(Nos.62071354)Open Research Projects of Zhejiang Lab(No.2019KD0AD01/013)+1 种基金the Key Research and Development Program of Shaanxi(ProgramNo.2022ZDLGY05-08)also supported by the ISN State Key Laboratory.
文摘With the development of the Cyber-Physical Internet of Things System(CPIoTS),the number of Cyber-Physical System(CPS)applications accessed in networks has increased dramatically.Latency-sensitive resource orchestration in CPS applications is extraordinarily essential for maintaining the Quality of Experience(QoE)for users.Although edge-cloud computing performs effectively in achieving latency-aware resource allocation in CPIoTS,existing methods fail to jointly consider the security and reliability requirements,thereby increasing the process latency of tasks and degrading the QoE of users.This paper aims to minimize the system latency of edge-cloud computing coupled with CPS while simultaneously considering the security and reliability requirements.We first consider a time-varying channel model as a Finite-State Markov Channel(FSMC)and propose a distributed blockchain-assisted CPIoTS to realize secure consensus and reliable resource orchestration by offloading computation tasks in edge-cloud computing.Moreover,we propose an efficient resource allocation algorithm,PPO-SRRA,that optimizes computing offloading and multi-dimension resource(e.g.,communication,computation,and consensus resource)allocation by using a policy-based Deep Reinforcement Learning(DRL)method.The experimental results show that the proposed resource allocation scheme can reduce the system latency and ensure consensus security.
基金Supported by a grant from the National Nature Sciences Foundation of China (No. 30571697).
文摘Objective: The aim of this work was to evaluate anti-tumor effects of mDRA-6 plus nimesulide on a human hepatocellular cancer cell line, SMMC-7721, and study the main mechanisms. Methods: The DR5 receptor of SMMC-7721 cells was detected by flow cytometry (FCM). For further experimental application, SMMC-7721 cells were treated with proper dose of mDRA-6, nimesulide, or mDRA-6 plus 200 μmol/L nimesulide; untreated SMMC-7721 cells were comparably set as control. Cytotoxicity was tested by MTT assay; cell morphology was examined using Hoechst 33258 staining; and apoptosis was determined by FCM. Results: The positive rate of DR5 on SMMC-7721 was 95.0%. Either mDRA-6 or nimesulide alone induces SMMC-7721 cell death in a dose-dependent manner. Treatment of 1,600 ng/mL mDRA-6 for 12h led to a cell-death rate of 35.0%, while an increased cell-death rate (91.1%) was found under the same condition of mDRA-6 treatment supple- mented with 200 μmol/L nimesulide. Hoechst 33258 and Annexin V/PI staining confirmed apoptosis as the main cause of this anti-tumor response. Conclusion: Both mDRA-6 and nimesulide can induce apoptosis of SMMC-7721 cells, and they have synergistic anti-tumor activities against SMMC-7721.
基金supported by the National Natural Science Foundation(Grant Nos.U1811261,62137001,61902055)the Fundamental Research Funds for the Central Universities(N180716010,N2117001).
文摘Cognitive diagnosis is the judgment of the student’s cognitive ability, is a wide-spread concern in educational science. The cognitive diagnosis model (CDM) is an essential method to realize cognitive diagnosis measurement. This paper presents new research on the cognitive diagnosis model and introduces four individual aspects of probability-based CDM and deep learning-based CDM. These four aspects are higher-order latent trait, polytomous responses, polytomous attributes, and multilevel latent traits. The paper also sorts on the contained ideas, model structures and respective characteristics, and provides direction for developing cognitive diagnosis in the future.
基金supported by the Project of Nature Scientific Foundation of Heilongjiang Province (No. C2017037)the National Natural Science Foundation of China (No. 31501839)
文摘The effects of tourmaline on nitrogen removal performance and biofilm structures were comparatively investigated in two identical laboratory-scale sequencing batch biofilm reactors(SBBRs)(denoted SBBR1 and SBBR2) at different nitrogen loading rates(NLRs) varying from(0.24 ± 0.01) to(1.26 ± 0.02) g N/(L·day). SBBR1 was operated in parallel with SBBR2, but SBBR1 was filled with polyurethane foam loaded tourmaline(TPU) carriers and another(SBBR2) filled with polyurethane foam(PU) carriers. Results obtained from this study showed that the excellent and stable performance of SBBR1 was obtained. Ammonia nitrogen removal and total nitrogen removal were higher in SBBR1 than that in SBBR2 with increase of NLR. At an NLR of(0.24 ± 0.01) g N/(L·day), the majority of the spherical and elliptical bacteria were surrounded by the extracellular polymeric substance(EPS) and bacillus or filamentous bacteria in two SBBRs biofilms. When NLR increased to(1.26 ± 0.02) g N/(L·day), the clusters were more obvious in the SBBR1 biofilm than that in the SBBR2 biofilm. Bacteria in SBBR1 were inclined to synthesis more EPS, and the formed EPS could protect the bacteria from free ammonia(FA) under extreme condition NLR(1.26 ± 0.02) g N/(L·day). The results of polymerase chain reaction-denaturing gradient gel electrophoresis analysis showed that the microbial community similarity in SBBR2 decreased more obviously than that in SBBR1 with the increase of NLR, which the microbial community in SBBR1 was relatively stable.
基金National Natural Science Foundation of China(61875049,61875124,61935011)Science,Technology and Innovation Commission of Shenzhen Municipality(JCYJ2016042718380345,JCYJ20180306171923592,JCYJ20180507183418012,JSGG20190819175801678,KQJSCX20180328165451777).
文摘Recently,2-μm wave band has gained increasing interest due to its potential application for next-generation optical communication.But the development of 2-μm optical communications is substantially hampered by the modulation speed due to the device bandwidth constraints.Thus,a high-speed modulator is highly demanded at 2μm.Motivated by this prospect,we demonstrate a high-speed silicon Mach–Zehnder modulator for a 2-μm wave band.The device is configured as a single-ended push–pull structure with waveguide electrorefraction via the free carrier plasma effect.The modulator was fabricated via a multiproject wafer shuttle run at a commercial silicon photonic foundry.The modulation efficiency of a single arm is measured to be 1.6 V·cm.The high-speed characterization is also performed,and the modulation speed can reach 80 Gbit/s with 4-level pulse amplitude modulation(PAM-4)formats.
基金supported in part by NSF grant DMS-0511815.The research of C.-W.Shu was supported in part by the Chinese Academy of Sciences while this author was visiting the University of Science and Technology of China(grant 2004-1-8)+3 种基金the Institute of Computational Mathematics and Scientific/Engineering ComputingAdditional support was provided by ARO grant W911NF-04-1-0291 and NSF grant DMS0510345The research of E.Tadmor was supported in part by NSF grant 04-07704 and ONR grant N00014-91-J-1076The research of M.Zhang was supported in part by the Chinese Academy of Sciences grant 2004-1-8.
文摘This is the continuation of the paper”Central discontinuous Galerkin methods on overlapping cells with a non-oscillatory hierarchical reconstruction”by the same authors.The hierarchical reconstruction introduced therein is applied to central schemes on overlapping cells and to finite volume schemes on non-staggered grids.This takes a new finite volume approach for approximating non-smooth solutions.A critical step for high-order finite volume schemes is to reconstruct a non-oscillatory high degree polynomial approximation in each cell out of nearby cell averages.In the paper this procedure is accomplished in two steps:first to reconstruct a high degree polynomial in each cell by using e.g.,a central reconstruction,which is easy to do despite the fact that the reconstructed polynomial could be oscillatory;then to apply the hierarchical reconstruction to remove the spurious oscillations while maintaining the high resolution.All numerical computations for systems of conservation laws are performed without characteristic decomposition.In particular,we demonstrate that this new approach can generate essentially non-oscillatory solutions even for 5th-order schemes without characteristic decomposition.
基金supported by Special Project on the Integration of Industry,Education and Research of Guangdong Province (2013B090800017)Shenzhen Special Program for Future Industrial Development(JSGG20141020113728803)Quality Inspection Programs of Scientific Research Project(2015IK246)
文摘On June 17 of 2016,a group of scientists from Chinese Academy of Fishery Sciences(CAFS)and Shenzhen BGI Fisheries Sci&Tech Co.Ltd.(BGI Fisheries)met together in Shenzhen,China to launch a novel project,the China Aquatic 10-100-1,000 Genomics Program,to conduct molecular breeding of^10 aquaculture species and sequence genomes of^100 and transcriptomes of^1,000 aquatic species.The main objective of this project is to build
基金supported in part by Simons Foundation grant 282311 and 584960supported in part by NSF grant NSF-DMS 1818751 and NSF-DMS 2012652+1 种基金supported in part by HKBU 162784 and 179356supported in part by NSF grants DMS-1522585 and DMS-CDS&E-MSS-1622453.
文摘Aggregation equations are broadly used tomodel population dynamicswith nonlocal interactions,characterized by a potential in the equation.This paper considers the inverse problem of identifying the potential from a single noisy spatialtemporal process.The identification is challenging in the presence of noise due to the instability of numerical differentiation.We propose a robust model-based technique to identify the potential by minimizing a regularized data fidelity term,and regularization is taken as the total variation and the squared Laplacian.A split Bregman method is used to solve the regularized optimization problem.Our method is robust to noise by utilizing a Successively Denoised Differentiation technique.We consider additional constraints such as compact support and symmetry constraints to enhance the performance further.We also apply thismethod to identify time-varying potentials and identify the interaction kernel in an agent-based system.Various numerical examples in one and two dimensions are included to verify the effectiveness and robustness of the proposed method.
基金This work was supported by the Sichuan University-Luzhoulaojiao Company Fund[grant number 17H1039]Science and Technology Support Project of Sichuan Province[grant number 2016KJT0086].
文摘To enhance the fruity flavour of pear wine by coculturing Saccharomyces yeasts with non-Saccharomyces,the coculture patterns were optimised based on the effect of different strains on the physicochemical properties and metabolites,and the interaction relationship in the coculture fermentation was also studied.These results showed that total volatiles of S.bayanus were higher than those of S.cerevisiae,especially esters,acids and phenols.The contents of total volatiles and esters were enhanced by sequential inoculation.The effect of coculturing S.bayanus Y4 with T.delbrueckii Y7 or Pichia sp.was better than that of coculturing with them with S.cerevisiae Y1,enhancing the contents of phenylethanol,acetate and ethyl esters.Furthermore,the esters(mainly ethyl esters)content was increased by 53.30%,and the acids content was decreased by 32.82%when S.bayanus Y4 was cocultured with T.delbrueckii Y7 by sequential inoculation compared with S.bayanus Y4 single inoculation.Their coculture increased theα-diversity of the fungal community and changed the correlation network between the microbiota.Redundancy analysis showed that Torulaspora was closely correlated to ethyl hexanoate,ethyl decanoate and ethyl 9-decenoate,while Saccharomyces was associated with hexanoic acid and octanoic acid.PICRUSt2 prediction revealed that Torulaspora may utilize the fatty acids produced by Saccharomyces to synthesize fatty acid ethyl esters.
基金The work was supported by the National Key R&D Program of China(No.2018YFE0207900)the National Natural Science Foundation of China(No.51835010)+6 种基金the Key R&D Program of Guangdong Province,China(No.2018B090906001)China Postdoctoral Science Foundation(No.2020M683458)the Natural Science Basic Research Program of ShaanXi Province,China(No.2022JQ-378)the Engineering and Physical Science Research Council(EPSRC)via DTP Case Programme(No.EP/T517793/1)the Fundamental Research Funds for the Central Universities(No.XZY012021007)the Laboratory Construction Project for Jihua Laboratory(No.X200031TM200),Open Project(No.BHJ17C019)the Youth Innovation Team of Shaanxi Universities.
文摘Polyether-ether-ketone(PEEK)is believed to be the next-generation biomedical material for orthopaedic implants that may replace metal materials because of its good biocompatibility,appropriate mechanical properties and radiolucency.Currently,some PEEK implants have been used successfully for many years.However,there is no customised PEEK orthopaedic implant made by additive manufacturing licensed for the market,although clinical trials have been increasingly reported.In this review article,design criteria,including geometric matching,functional restoration,strength safety,early fixation,long-term stability and manufacturing capability,are summarised,focusing on the clinical requirements.An integrated framework of design and manufacturing processes to create customised PEEK implants is presented,and several typical clinical applications such as cranioplasty patches,rib prostheses,mandibular prostheses,scapula prostheses and femoral prostheses are described.The main technical challenge faced by PEEK orthopaedic implants lies in the poor bonding with bone and soft tissue due to its biological inertness,which may be solved by adding bioactive fillers and manufacturing porous architecture.The lack of technical standards is also one of the major factors preventing additive-manufactured customised PEEK orthopaedic implants from clinical translation,and it is good to see that the abundance of standards in the field of additive-manufactured medical devices is helping them enter the clinical market.
