A transformation of the electron states—say those enclosed in a potential box—into the de Broglie waves done in the paper, enabled us to calculate the energy change between two quantum levels as a function of the sp...A transformation of the electron states—say those enclosed in a potential box—into the de Broglie waves done in the paper, enabled us to calculate the energy change between two quantum levels as a function of the specific heat and difference of the temperature between the states. In consequence, the energy difference and that of entropy between the levels could be examined in terms of the appropriate classical parameters. In the next step, the time interval necessary for the electron transition between the levels could be associated with the classical electrodynamical parameters like the electric resistance and capacitance connected with the temporary formation of the electric cell in course of the transition. The parameters characterizing the mechanical inertia of the electron were next used as a check of the electrodynamical formulae referring to transition.展开更多
BACKGROUND Hepatocellular carcinoma(HCC),the sixth most common cancer and fourthleading cause of cancer-related mortality globally,imposes a significant burden in Vietnam due to endemic hepatitis B virus(HBV)and hepat...BACKGROUND Hepatocellular carcinoma(HCC),the sixth most common cancer and fourthleading cause of cancer-related mortality globally,imposes a significant burden in Vietnam due to endemic hepatitis B virus(HBV)and hepatitis C virus(HCV)infections.Accurate prognostication is crucial for optimizing treatment and outcomes.Numerous staging systems exist,including the Barcelona Clinic Liver Cancer(BCLC),Hong Kong Liver Cancer(HKLC),cancer of the liver Italian Program(CLIP),Italian Liver Cancer(ITA.LI.CA),Japan Integrated Staging(JIS),Tokyo Score,and model to estimate survival in ambulatory HCC patients(MESIAH).However,their comparative performance in Vietnamese patients remains underexplored.AIM To compare the prognostic accuracy of seven HCC staging systems in predicting survival and identify the optimal model.METHODS This retrospective cohort study included 987 patients with HCC diagnosed at Nhan dan Gia Dinh Hospital,Vietnam,from January 2016 to December 2023.Patients were staged using BCLC,HKLC,CLIP,ITA.LI.CA,JIS,Tokyo score,and MESIAH.Overall survival was analyzed using Kaplan-Meier methods,and prognostic performance was evaluated via the area under the receiver operating characteristic(ROC)curve,Harrell’s concordance index,and calibration plots.RESULTS The HKLC and BCLC systems demonstrated the highest discriminatory ability,with area under the ROC curves of 0.834 and 0.830,respectively,at 12 months and 0.859 for both systems at 36 months.CLIP and ITA.LI.CA exhibited superior calibration,particularly at 36 months.The JIS system consistently showed the poorest discriminatory performance.Subgroup analyses revealed that HKLC maintained strong performance across different viral etiologies(HBV,HCV,non-B-non-C)and treatment modalities(transarterial chemoembolization,surgery,ablation).CONCLUSION The HKLC and BCLC systems showed superior prognostic performance for Vietnamese patients with HCC,supporting HKLC adoption in clinical practice.展开更多
Many evidences for gas hydrate bearing sediments had been found in the continental slope of the East China Sea,such as bottom simulating reflections(BSRs),undersea gas springs,pyrite associated with methane leakage,mu...Many evidences for gas hydrate bearing sediments had been found in the continental slope of the East China Sea,such as bottom simulating reflections(BSRs),undersea gas springs,pyrite associated with methane leakage,mud diapirs/mud volcanos,bottom-water methane anomalies and so on.In this study,six key stratigraphic interfaces including T_0(seafloor),T_1(LGM,23 kyr B.P.),T_2(2.58 Myr),T_3(5.33 Myr),T_4(11.02 Myr)and T_5(16.12 Myr)were identified,and then five third-order sequences of SQIII1 to SQIII5 were divided.However,T5 in southern continental slope is not found,which shows that the middle-northern Okinawa Trough had begun to rift in the early Miocene,earlier than the southern segment.Four system tracts including lowstand systems tract(LST),transgressive systems tract(TST),highstand systems tract(HST)and falling stage systems tract(FSST)are further divided.The marine erosion interface of 11.02 Myr and regressive unconformity interface of 23 kyr B.P.indicate two large-scale sea level drop events in the research area.Seven typical seismic facies identified in the continental slope are continental shelf-edge deltas,littoral fluvial-delta plains,incised channels or submarine canyons,slope fans,submarine fans or coastal sandbars,littoral-neritic finegrained sediments,mud volcanos and some other geological bodies respectively.The minimum water depth for hydrate occurrence in the Okinawa Trough is 630 m,and the thickness of gas hydrate stability zone in continental slope is between 0 and 590 m.The calculated bottom boundary of hydrate stability zone is slightly deeper than BSRs on the seismic sections.The re-depositional turbidite sand bodies,such as canyon channels,slope fans and submarine fans developed in Quaternary strata,are the predominant hydrate reservoirs.According to developing process,the dynamic accumulation of hydrate systems can be divided into three evolutionary stages including canyon erosion and hydrate stability zone migration stage,sediments destabilizing and methane leakage stage,and channel filling and hydrate re-occurrence stage.展开更多
Safety assessment of genetically modified organisms (GMOs) is a contentious topic. Proponents of GMOs assert that GMOs are safe since the FDA’s policy of substantial equivalence considers GMOs “equivalent” to their...Safety assessment of genetically modified organisms (GMOs) is a contentious topic. Proponents of GMOs assert that GMOs are safe since the FDA’s policy of substantial equivalence considers GMOs “equivalent” to their non-GMO counterparts, and argue that genetic modification (GM) is simply an extension of a “natural” process of plant breeding, a form of “genetic modification”, though done over longer time scales. Anti-GMO activists counter that GMOs are unsafe since substantial equivalence is unscientific and outdated since it originates in the 1970s to assess safety of medical devices, which are not comparable to the complexity of biological systems, and contend that targeted GM is not plant breeding. The heart of the debate appears to be on the methodology used to determine criteria for substantial equivalence. Systems biology, which aims to understand complexity of the whole organism, as a system, rather than just studying its parts in a reductionist manner, may provide a framework to determine appropriate criteria, as it recognizes that GM, small or large, may affect emergent properties of the whole system. Herein, a promising computational systems biology method couples known perturbations on five biomolecules caused by the CP4 EPSPS GM of Glycine max L. (soybean), with an integrative model of C1 metabolism and oxidative stress (two molecular systems critical to plant function). The results predict significant accumulation of formaldehyde and concomitant depletion of glutathione in the GMO, suggesting how a “small” and single GM creates “large” and systemic perturbations to molecular systems equilibria. Regulatory agencies, currently reviewing rules for GMO safety, may wish to adopt a systems biology approach using a combination of in silico, computational methods used herein, and subsequent targeted experimental in vitro and in vivo designs, to develop a systems understanding of “equivalence” using biomarkers, such as formaldehyde and glutathione, which predict metabolic disruptions, towards modernizing the safety assessment of GMOs.展开更多
Dear Editor,This letter studies finite-time stability (FTS) of impulsive and switched hybrid systems with delay-dependent impulses. Some conditions, based on Lyapunov method, are proposed for ensuring FTS and estimati...Dear Editor,This letter studies finite-time stability (FTS) of impulsive and switched hybrid systems with delay-dependent impulses. Some conditions, based on Lyapunov method, are proposed for ensuring FTS and estimating settling-time function (STF) of the hybrid systems.When switching dynamics are FTS and impulsive dynamics involve destabilizing delay-dependent impulses, the FTS is retained if the impulses occur infrequently.展开更多
The human retina,a complex and highly specialized structure,includes multiple cell types that work synergistically to generate and transmit visual signals.However,genetic predisposition or age-related degeneration can...The human retina,a complex and highly specialized structure,includes multiple cell types that work synergistically to generate and transmit visual signals.However,genetic predisposition or age-related degeneration can lead to retinal damage that severely impairs vision or causes blindness.Treatment options for retinal diseases are limited,and there is an urgent need for innovative therapeutic strategies.Cell and gene therapies are promising because of the efficacy of delivery systems that transport therapeutic genes to targeted retinal cells.Gene delivery systems hold great promise for treating retinal diseases by enabling the targeted delivery of therapeutic genes to affected cells or by converting endogenous cells into functional ones to facilitate nerve regeneration,potentially restoring vision.This review focuses on two principal categories of gene delivery vectors used in the treatment of retinal diseases:viral and non-viral systems.Viral vectors,including lentiviruses and adeno-associated viruses,exploit the innate ability of viruses to infiltrate cells,which is followed by the introduction of therapeutic genetic material into target cells for gene correction.Lentiviruses can accommodate exogenous genes up to 8 kb in length,but their mechanism of integration into the host genome presents insertion mutation risks.Conversely,adeno-associated viruses are safer,as they exist as episomes in the nucleus,yet their limited packaging capacity constrains their application to a narrower spectrum of diseases,which necessitates the exploration of alternative delivery methods.In parallel,progress has also occurred in the development of novel non-viral delivery systems,particularly those based on liposomal technology.Manipulation of the ratios of hydrophilic and hydrophobic molecules within liposomes and the development of new lipid formulations have led to the creation of advanced non-viral vectors.These innovative systems include solid lipid nanoparticles,polymer nanoparticles,dendrimers,polymeric micelles,and polymeric nanoparticles.Compared with their viral counterparts,non-viral delivery systems offer markedly enhanced loading capacities that enable the direct delivery of nucleic acids,mRNA,or protein molecules into cells.This bypasses the need for DNA transcription and processing,which significantly enhances therapeutic efficiency.Nevertheless,the immunogenic potential and accumulation toxicity associated with non-viral particulate systems necessitates continued optimization to reduce adverse effects in vivo.This review explores the various delivery systems for retinal therapies and retinal nerve regeneration,and details the characteristics,advantages,limitations,and clinical applications of each vector type.By systematically outlining these factors,our goal is to guide the selection of the optimal delivery tool for a specific retinal disease,which will enhance treatment efficacy and improve patient outcomes while paving the way for more effective and targeted therapeutic interventions.展开更多
Dear Editor,In this letter,a constrained networked predictive control strategy is proposed for the optimal control problem of complex nonlinear highorder fully actuated(HOFA)systems with noises.The method can effectiv...Dear Editor,In this letter,a constrained networked predictive control strategy is proposed for the optimal control problem of complex nonlinear highorder fully actuated(HOFA)systems with noises.The method can effectively deal with nonlinearities,constraints,and noises in the system,optimize the performance metric,and present an upper bound on the stable output of the system.展开更多
A brief review of the works of the author and his co-authors on the application of nonlinear analysis, numerical and analytical methods for solving the nonlinear inverse problems (synthesis problems) for optimizing th...A brief review of the works of the author and his co-authors on the application of nonlinear analysis, numerical and analytical methods for solving the nonlinear inverse problems (synthesis problems) for optimizing the different types of radiating systems, is presented in the paper. The synthesis problems are formulated in variational statements and further they are reduced to research and numerical solution of nonlinear integral equations of Hammerstein type. The existence theorems are proof, the investigation methods of nonuniqueness problem of solutions and numerical algorithms of finding the optimal solutions are proved.展开更多
In this paper, H∞ optimal model reduction for singular fast subsystems will be inves-tigated. First, error system is established to measure the error magnitude between the original andreduced systems, and it is demon...In this paper, H∞ optimal model reduction for singular fast subsystems will be inves-tigated. First, error system is established to measure the error magnitude between the original andreduced systems, and it is demonstrated that the new feature for model reduction of singular systemsis to make H∞ norm of the error system finite and minimal. The necessary and su?cient conditionis derived for the existence of the H∞ suboptimal model reduction problem. Next, we give an exactand practicable algorithm to get the parameters of the reduced subsystems by applying the matrixtheory. Meanwhile, the reduced system may be also impulsive. The advantages of the proposedalgorithm are that it is more ?exible in a straight-forward way without much extra computation, andthe order of the reduced systems is as minimal as possible. Finally, one illustrative example is givento illustrate the e?ectiveness of the proposed model reduction approach.展开更多
Dear Editor,This letter presents a joint probabilistic scheduling and resource allocation method(PSRA) for 5G-based wireless networked control systems(WNCSs). As a control-aware optimization method, PSRA minimizes the...Dear Editor,This letter presents a joint probabilistic scheduling and resource allocation method(PSRA) for 5G-based wireless networked control systems(WNCSs). As a control-aware optimization method, PSRA minimizes the linear quadratic Gaussian(LQG) control cost of WNCSs by optimizing the activation probability of subsystems, the number of uplink repetitions, and the durations of uplink and downlink phases. Simulation results show that PSRA achieves smaller LQG control costs than existing works.展开更多
Various optimal boundary control problems for linear infinite order distributed hyperbolic systems involving constant time lags are considered. Constraints on controls are imposed. Necessary and sufficient optimality ...Various optimal boundary control problems for linear infinite order distributed hyperbolic systems involving constant time lags are considered. Constraints on controls are imposed. Necessary and sufficient optimality conditions for the Neumann problem with the quadratic performance functional are derived.展开更多
At present, mud pulse transmission systems are widely used in downhole data transmission. But the systems are very low in transmission efficiency, only 5-10 bits/s, with very large anti-inter-symbol-interference (ISI)...At present, mud pulse transmission systems are widely used in downhole data transmission. But the systems are very low in transmission efficiency, only 5-10 bits/s, with very large anti-inter-symbol-interference (ISI). It cannot meet high requirements for high-speed transmission of modern logging system. The development of communication technology has laid some foundation for this requirement. For this purpose, the Orthogonal Frequency Division Multiplexing (OFDM) Wireless Downhole Transmission Systems are proposed for the first time because of their high transmission rate, anti-inter-symbol-interference (ISI), and high spectral efficiency, etc. Due to non-linear power amplifier (PA) of logging systems with limited dynamic range, the drawbacks of high peak-average power ratio (PAPR) may outweigh all the potential benefits of OFDM wireless downhole transmission systems. Selective mapping (SLM) method can reduce the PAPR of OFDM logging signals without distortion. But at the receiver, the conventional SLM method needs exact bits of side information (SI) to recover the data signal. The probability of erroneous SI detection has a significant influence on the error performance of the system. And individual transmissions of SI result in the reduction of bandwidth efficiency. To restore the exact data signal, our scheme codes the SI bits by linear block codes (LBC), and is easily decoded by syndrome decoding. And then the coding SI bits are superimposed onto the logging signals to omit SI bits transmission. The theory and simulation results show that the proposed method has better performance than the conventional one. Accordingly, the OFDM wireless downhole transmission systems can tackle the high PAPR problem, and highten the transmission rate of logging signals.展开更多
In this paper, we study the existence of solutions for 2l order (n × n) cooperative systems governed by Dirichlet and Neumann problems involving hyperbolic operators with an infinite number of variables and with ...In this paper, we study the existence of solutions for 2l order (n × n) cooperative systems governed by Dirichlet and Neumann problems involving hyperbolic operators with an infinite number of variables and with variable coefficients. The necessary and sufficient conditions for optimality of the distributed control with constraints are obtained and the set of inequalities that defining the optimal control of these systems are also obtained.展开更多
Considering the influence of more random atmospheric turbulence, worse pointing errors and highly dynamic link on the transmission performance of mobile multiple-input multiple-output (MIMO) free space optics (FSO...Considering the influence of more random atmospheric turbulence, worse pointing errors and highly dynamic link on the transmission performance of mobile multiple-input multiple-output (MIMO) free space optics (FSO) communica- tion systems, this paper establishes a channel model for the mobile platform. Based on the combination of Alamouti space-time code and time hopping ultra-wide band (TH-UWB) communications, a novel repetition space-time coding (RSTC) method for mobile 2x2 free-space optical communications with pulse position modulation (PPM) is devel- oped. In particular, two decoding methods of equal gain combining (EGC) maximum likelihood detection (MLD) and correlation matrix detection (CMD) are derived. When a quasi-static fading and weak turbulence channel model are considered, simulation results show that whether the channel state information (CSI) is known or not, the coding sys- tem demonstrates more significant performance of the symbol error rate (SER) than the uncoding. In other words, transmitting diversity can be achieved while conveying the information only through the time delays of the modulated signals transmitted from different antennas. CMD has almost the same effect of signal combining with maximal ratio combining (MRC). However, when the channel correlation increases, SER performance of the coding 2×2 system de- grades significantly.展开更多
The intricate interplay between neurotransmitter systems,neural circuits,and neuroendocrine pathways underpins brain function and dysfunction in neurological and psychiatric disorders.This review synthesizes contempor...The intricate interplay between neurotransmitter systems,neural circuits,and neuroendocrine pathways underpins brain function and dysfunction in neurological and psychiatric disorders.This review synthesizes contemporary advances in neuropharmacology,focusing on dopaminergic,serotonergic,glutamatergic,and GABAergic systems,and their roles in regulating motor control,cognition,emotion,and stress responses.Dopaminergic pathways,including the nigrostriatal,mesolimbic,and mesocortical circuits,are explored in the context of Parkinson’s disease,schizophrenia,and addiction,with emphasis on pharmacological agents such as L-DOPA,antipsychotics,and amphetamines.Serotonergic modulation through SSRIs and psychedelics is examined for its impact on mood and neuroplasticity,while glutamatergic and GABAergic systems are discussed in relation to synaptic plasticity,excitotoxicity,and therapeutic innovations like ketamine and benzodiazepines.The neuroendocrine system,particularly the hypothalamic-pituitary-adrenal(HPA)axis,is highlighted for its role in stress-related disorders and interactions with neurotransmitter networks.Despite progress,significant challenges persist,including translational gaps between preclinical models and human trials,species-specifi c receptor disparities,and ethical dilemmas surrounding cognitive enhancers and genetic manipulation.Emerging frontiers such as nanotechnology-enabled drug delivery,optogenetics,and gut-brain axis modulation are reviewed as transformative approaches to overcome these barriers.Personalized medicine,integrating neuroimaging biomarkers and pharmacogenomics,promises to tailor therapies to individual neural and genetic profi les,while biased agonists and closed-loop systems exemplify the shift toward circuit-specifi c interventions.Ethical considerations,including equitable access to advanced therapies and responsible innovation,are underscored as critical to ensuring societal benefi t.By harmonizing molecular precision with systems neuroscience,this review advocates for interdisciplinary strategies to advance neuropharmacology,ultimately aiming to restore dynamic neural and neuroendocrine homeostasis in health and disease.展开更多
This article presents views on the future development of data science,with a particular focus on its importance to artificial intel-ligence(AI).After discussing the challenges of data science,it elu-cidates a possible...This article presents views on the future development of data science,with a particular focus on its importance to artificial intel-ligence(AI).After discussing the challenges of data science,it elu-cidates a possible approach to tackle these challenges by clarifying the logic and principles of data related to the multi-level complex-ity of the world.Finally,urgently required actions are briefly outlined.展开更多
The ability to accurately simulate the time evolu-tion of quantum systems stands as a cornerstone of modern molecular science.It provides the essential mechanistic bridge between a system’s microscopic structure and ...The ability to accurately simulate the time evolu-tion of quantum systems stands as a cornerstone of modern molecular science.It provides the essential mechanistic bridge between a system’s microscopic structure and its macroscopic function,a challenge first envisioned by Feynman.The central difficulty,and the unifying theme of this Special Topic,is the problem of“complexity”:a multifaceted challenge arising from the interplay of strongly coupled electronic and vibrational degrees of freedom,quantum statistics,and the non-trivial,often non-Markovian,memory effects exerted by a surrounding environment.展开更多
Dear Editor,The letter deals with the distributed state and fault estimation of the whole physical layer for cyber-physical systems(CPSs) when the cyber layer suffers from DoS attacks. With the advancement of embedded...Dear Editor,The letter deals with the distributed state and fault estimation of the whole physical layer for cyber-physical systems(CPSs) when the cyber layer suffers from DoS attacks. With the advancement of embedded computing, communication and related hardware technologies, CPSs have attracted extensive attention and have been widely used in power system, traffic network, refrigeration system and other fields.展开更多
The patterns of metal distribution and alteration zonation in magmatic-hydrothermal systems primarily focus on porphyry deposit and other closely associated types,such as skarn,epithermal and distal vein deposits(e.g....The patterns of metal distribution and alteration zonation in magmatic-hydrothermal systems primarily focus on porphyry deposit and other closely associated types,such as skarn,epithermal and distal vein deposits(e.g.,Zheng,2022;Hutchison et al.,2020;Cooke et al.,2011;Hedenquist et al.,1998).展开更多
Objectives:Recently,the global esports industry has experienced remarkable growth,leading to an expansion in the scale and influence of professional player communities.However,despite this outward growth,systems to pr...Objectives:Recently,the global esports industry has experienced remarkable growth,leading to an expansion in the scale and influence of professional player communities.However,despite this outward growth,systems to protect players’mental health remain inadequate.Comprehensive analysis of structural risk factors,including performance pressure,public evaluation,and career instability,remains insufficient.This study,aimed to explore stressors encountered by esports athletes,coping strategies,and the role of social support systems in safeguarding mental health.Using the transactional model of stress and coping,the job demands–resources model,and social support theory,the study adopts an integrated perspective to examine challenges faced by athletes in the competitive esports environment.Methods:A qualitative case study was conducted involving in-depth interviews and nonparticipant observations with 11 esports athletes who competed at national or international levels,as well as two team managers.Thematic analysis identified recurring patterns in the data,and credibility was ensured through triangulation and cross-review among researchers.Results:Esports athletes experience multiple interacting stressors,including performance demands,emotional strain duringmatches,and continuous evaluation on socialmedia.In response,they employed coping strategies—problem-focused,emotion-focused,and avoidance-based,which provided temporary relief but often led to burnout and self-regulation failure owing to absence of support systems.Social support networks had ambivalent effects:while offering comfort,they also intensified pressure through negative feedback and high expectations from fans and online communities.Conclusion:The findings show that mental health issues among esports athletes are not only related to individual factors but are closely linked to performance-driven structures,competitive environments,and social relationships.This study integrates the transactional model of stress and coping,the JobDemands–Resourcesmodel,and social support theoryto provide comprehensive analysis.It also offers practical recommendations,including psychological counseling,emotional labor programs,and improved communication with families and fan communities.展开更多
文摘A transformation of the electron states—say those enclosed in a potential box—into the de Broglie waves done in the paper, enabled us to calculate the energy change between two quantum levels as a function of the specific heat and difference of the temperature between the states. In consequence, the energy difference and that of entropy between the levels could be examined in terms of the appropriate classical parameters. In the next step, the time interval necessary for the electron transition between the levels could be associated with the classical electrodynamical parameters like the electric resistance and capacitance connected with the temporary formation of the electric cell in course of the transition. The parameters characterizing the mechanical inertia of the electron were next used as a check of the electrodynamical formulae referring to transition.
文摘BACKGROUND Hepatocellular carcinoma(HCC),the sixth most common cancer and fourthleading cause of cancer-related mortality globally,imposes a significant burden in Vietnam due to endemic hepatitis B virus(HBV)and hepatitis C virus(HCV)infections.Accurate prognostication is crucial for optimizing treatment and outcomes.Numerous staging systems exist,including the Barcelona Clinic Liver Cancer(BCLC),Hong Kong Liver Cancer(HKLC),cancer of the liver Italian Program(CLIP),Italian Liver Cancer(ITA.LI.CA),Japan Integrated Staging(JIS),Tokyo Score,and model to estimate survival in ambulatory HCC patients(MESIAH).However,their comparative performance in Vietnamese patients remains underexplored.AIM To compare the prognostic accuracy of seven HCC staging systems in predicting survival and identify the optimal model.METHODS This retrospective cohort study included 987 patients with HCC diagnosed at Nhan dan Gia Dinh Hospital,Vietnam,from January 2016 to December 2023.Patients were staged using BCLC,HKLC,CLIP,ITA.LI.CA,JIS,Tokyo score,and MESIAH.Overall survival was analyzed using Kaplan-Meier methods,and prognostic performance was evaluated via the area under the receiver operating characteristic(ROC)curve,Harrell’s concordance index,and calibration plots.RESULTS The HKLC and BCLC systems demonstrated the highest discriminatory ability,with area under the ROC curves of 0.834 and 0.830,respectively,at 12 months and 0.859 for both systems at 36 months.CLIP and ITA.LI.CA exhibited superior calibration,particularly at 36 months.The JIS system consistently showed the poorest discriminatory performance.Subgroup analyses revealed that HKLC maintained strong performance across different viral etiologies(HBV,HCV,non-B-non-C)and treatment modalities(transarterial chemoembolization,surgery,ablation).CONCLUSION The HKLC and BCLC systems showed superior prognostic performance for Vietnamese patients with HCC,supporting HKLC adoption in clinical practice.
基金supported by the National Natural Science Foundation of China (Nos. 41806073, 41530963)the Natural Science Foundation of Shandong Province (No. ZR 2017BD014)+1 种基金the Shandong Provincial Key Laboratory of Depositional Mineralization & Sedimentary Minerals, Shandong University of Science and Technology (No. DMSM 2017042)the Fundamental Research Funds for the Central Universities (Nos. 201964016, 201851023)
文摘Many evidences for gas hydrate bearing sediments had been found in the continental slope of the East China Sea,such as bottom simulating reflections(BSRs),undersea gas springs,pyrite associated with methane leakage,mud diapirs/mud volcanos,bottom-water methane anomalies and so on.In this study,six key stratigraphic interfaces including T_0(seafloor),T_1(LGM,23 kyr B.P.),T_2(2.58 Myr),T_3(5.33 Myr),T_4(11.02 Myr)and T_5(16.12 Myr)were identified,and then five third-order sequences of SQIII1 to SQIII5 were divided.However,T5 in southern continental slope is not found,which shows that the middle-northern Okinawa Trough had begun to rift in the early Miocene,earlier than the southern segment.Four system tracts including lowstand systems tract(LST),transgressive systems tract(TST),highstand systems tract(HST)and falling stage systems tract(FSST)are further divided.The marine erosion interface of 11.02 Myr and regressive unconformity interface of 23 kyr B.P.indicate two large-scale sea level drop events in the research area.Seven typical seismic facies identified in the continental slope are continental shelf-edge deltas,littoral fluvial-delta plains,incised channels or submarine canyons,slope fans,submarine fans or coastal sandbars,littoral-neritic finegrained sediments,mud volcanos and some other geological bodies respectively.The minimum water depth for hydrate occurrence in the Okinawa Trough is 630 m,and the thickness of gas hydrate stability zone in continental slope is between 0 and 590 m.The calculated bottom boundary of hydrate stability zone is slightly deeper than BSRs on the seismic sections.The re-depositional turbidite sand bodies,such as canyon channels,slope fans and submarine fans developed in Quaternary strata,are the predominant hydrate reservoirs.According to developing process,the dynamic accumulation of hydrate systems can be divided into three evolutionary stages including canyon erosion and hydrate stability zone migration stage,sediments destabilizing and methane leakage stage,and channel filling and hydrate re-occurrence stage.
文摘Safety assessment of genetically modified organisms (GMOs) is a contentious topic. Proponents of GMOs assert that GMOs are safe since the FDA’s policy of substantial equivalence considers GMOs “equivalent” to their non-GMO counterparts, and argue that genetic modification (GM) is simply an extension of a “natural” process of plant breeding, a form of “genetic modification”, though done over longer time scales. Anti-GMO activists counter that GMOs are unsafe since substantial equivalence is unscientific and outdated since it originates in the 1970s to assess safety of medical devices, which are not comparable to the complexity of biological systems, and contend that targeted GM is not plant breeding. The heart of the debate appears to be on the methodology used to determine criteria for substantial equivalence. Systems biology, which aims to understand complexity of the whole organism, as a system, rather than just studying its parts in a reductionist manner, may provide a framework to determine appropriate criteria, as it recognizes that GM, small or large, may affect emergent properties of the whole system. Herein, a promising computational systems biology method couples known perturbations on five biomolecules caused by the CP4 EPSPS GM of Glycine max L. (soybean), with an integrative model of C1 metabolism and oxidative stress (two molecular systems critical to plant function). The results predict significant accumulation of formaldehyde and concomitant depletion of glutathione in the GMO, suggesting how a “small” and single GM creates “large” and systemic perturbations to molecular systems equilibria. Regulatory agencies, currently reviewing rules for GMO safety, may wish to adopt a systems biology approach using a combination of in silico, computational methods used herein, and subsequent targeted experimental in vitro and in vivo designs, to develop a systems understanding of “equivalence” using biomarkers, such as formaldehyde and glutathione, which predict metabolic disruptions, towards modernizing the safety assessment of GMOs.
基金supported by the National Natural Science Foundation of China(61833005)
文摘Dear Editor,This letter studies finite-time stability (FTS) of impulsive and switched hybrid systems with delay-dependent impulses. Some conditions, based on Lyapunov method, are proposed for ensuring FTS and estimating settling-time function (STF) of the hybrid systems.When switching dynamics are FTS and impulsive dynamics involve destabilizing delay-dependent impulses, the FTS is retained if the impulses occur infrequently.
基金Hongguang Wu,Both authors contributed equally to this work and share first authorshipLing Dong,Both authors contributed equally to this work and share first authorship。
文摘The human retina,a complex and highly specialized structure,includes multiple cell types that work synergistically to generate and transmit visual signals.However,genetic predisposition or age-related degeneration can lead to retinal damage that severely impairs vision or causes blindness.Treatment options for retinal diseases are limited,and there is an urgent need for innovative therapeutic strategies.Cell and gene therapies are promising because of the efficacy of delivery systems that transport therapeutic genes to targeted retinal cells.Gene delivery systems hold great promise for treating retinal diseases by enabling the targeted delivery of therapeutic genes to affected cells or by converting endogenous cells into functional ones to facilitate nerve regeneration,potentially restoring vision.This review focuses on two principal categories of gene delivery vectors used in the treatment of retinal diseases:viral and non-viral systems.Viral vectors,including lentiviruses and adeno-associated viruses,exploit the innate ability of viruses to infiltrate cells,which is followed by the introduction of therapeutic genetic material into target cells for gene correction.Lentiviruses can accommodate exogenous genes up to 8 kb in length,but their mechanism of integration into the host genome presents insertion mutation risks.Conversely,adeno-associated viruses are safer,as they exist as episomes in the nucleus,yet their limited packaging capacity constrains their application to a narrower spectrum of diseases,which necessitates the exploration of alternative delivery methods.In parallel,progress has also occurred in the development of novel non-viral delivery systems,particularly those based on liposomal technology.Manipulation of the ratios of hydrophilic and hydrophobic molecules within liposomes and the development of new lipid formulations have led to the creation of advanced non-viral vectors.These innovative systems include solid lipid nanoparticles,polymer nanoparticles,dendrimers,polymeric micelles,and polymeric nanoparticles.Compared with their viral counterparts,non-viral delivery systems offer markedly enhanced loading capacities that enable the direct delivery of nucleic acids,mRNA,or protein molecules into cells.This bypasses the need for DNA transcription and processing,which significantly enhances therapeutic efficiency.Nevertheless,the immunogenic potential and accumulation toxicity associated with non-viral particulate systems necessitates continued optimization to reduce adverse effects in vivo.This review explores the various delivery systems for retinal therapies and retinal nerve regeneration,and details the characteristics,advantages,limitations,and clinical applications of each vector type.By systematically outlining these factors,our goal is to guide the selection of the optimal delivery tool for a specific retinal disease,which will enhance treatment efficacy and improve patient outcomes while paving the way for more effective and targeted therapeutic interventions.
基金supported in part by the National Natural Science Foundation of China(62173255,62188101)Shenzhen Key Laboratory of Control Theory and Intelligent Systems(ZDSYS20220330161800001)
文摘Dear Editor,In this letter,a constrained networked predictive control strategy is proposed for the optimal control problem of complex nonlinear highorder fully actuated(HOFA)systems with noises.The method can effectively deal with nonlinearities,constraints,and noises in the system,optimize the performance metric,and present an upper bound on the stable output of the system.
文摘A brief review of the works of the author and his co-authors on the application of nonlinear analysis, numerical and analytical methods for solving the nonlinear inverse problems (synthesis problems) for optimizing the different types of radiating systems, is presented in the paper. The synthesis problems are formulated in variational statements and further they are reduced to research and numerical solution of nonlinear integral equations of Hammerstein type. The existence theorems are proof, the investigation methods of nonuniqueness problem of solutions and numerical algorithms of finding the optimal solutions are proved.
文摘In this paper, H∞ optimal model reduction for singular fast subsystems will be inves-tigated. First, error system is established to measure the error magnitude between the original andreduced systems, and it is demonstrated that the new feature for model reduction of singular systemsis to make H∞ norm of the error system finite and minimal. The necessary and su?cient conditionis derived for the existence of the H∞ suboptimal model reduction problem. Next, we give an exactand practicable algorithm to get the parameters of the reduced subsystems by applying the matrixtheory. Meanwhile, the reduced system may be also impulsive. The advantages of the proposedalgorithm are that it is more ?exible in a straight-forward way without much extra computation, andthe order of the reduced systems is as minimal as possible. Finally, one illustrative example is givento illustrate the e?ectiveness of the proposed model reduction approach.
基金supported by the Liaoning Revitalization Talents Program(XLYC2203148)
文摘Dear Editor,This letter presents a joint probabilistic scheduling and resource allocation method(PSRA) for 5G-based wireless networked control systems(WNCSs). As a control-aware optimization method, PSRA minimizes the linear quadratic Gaussian(LQG) control cost of WNCSs by optimizing the activation probability of subsystems, the number of uplink repetitions, and the durations of uplink and downlink phases. Simulation results show that PSRA achieves smaller LQG control costs than existing works.
文摘Various optimal boundary control problems for linear infinite order distributed hyperbolic systems involving constant time lags are considered. Constraints on controls are imposed. Necessary and sufficient optimality conditions for the Neumann problem with the quadratic performance functional are derived.
文摘At present, mud pulse transmission systems are widely used in downhole data transmission. But the systems are very low in transmission efficiency, only 5-10 bits/s, with very large anti-inter-symbol-interference (ISI). It cannot meet high requirements for high-speed transmission of modern logging system. The development of communication technology has laid some foundation for this requirement. For this purpose, the Orthogonal Frequency Division Multiplexing (OFDM) Wireless Downhole Transmission Systems are proposed for the first time because of their high transmission rate, anti-inter-symbol-interference (ISI), and high spectral efficiency, etc. Due to non-linear power amplifier (PA) of logging systems with limited dynamic range, the drawbacks of high peak-average power ratio (PAPR) may outweigh all the potential benefits of OFDM wireless downhole transmission systems. Selective mapping (SLM) method can reduce the PAPR of OFDM logging signals without distortion. But at the receiver, the conventional SLM method needs exact bits of side information (SI) to recover the data signal. The probability of erroneous SI detection has a significant influence on the error performance of the system. And individual transmissions of SI result in the reduction of bandwidth efficiency. To restore the exact data signal, our scheme codes the SI bits by linear block codes (LBC), and is easily decoded by syndrome decoding. And then the coding SI bits are superimposed onto the logging signals to omit SI bits transmission. The theory and simulation results show that the proposed method has better performance than the conventional one. Accordingly, the OFDM wireless downhole transmission systems can tackle the high PAPR problem, and highten the transmission rate of logging signals.
文摘In this paper, we study the existence of solutions for 2l order (n × n) cooperative systems governed by Dirichlet and Neumann problems involving hyperbolic operators with an infinite number of variables and with variable coefficients. The necessary and sufficient conditions for optimality of the distributed control with constraints are obtained and the set of inequalities that defining the optimal control of these systems are also obtained.
基金supported by the National Natural Science Foundation of China(No.61205106)
文摘Considering the influence of more random atmospheric turbulence, worse pointing errors and highly dynamic link on the transmission performance of mobile multiple-input multiple-output (MIMO) free space optics (FSO) communica- tion systems, this paper establishes a channel model for the mobile platform. Based on the combination of Alamouti space-time code and time hopping ultra-wide band (TH-UWB) communications, a novel repetition space-time coding (RSTC) method for mobile 2x2 free-space optical communications with pulse position modulation (PPM) is devel- oped. In particular, two decoding methods of equal gain combining (EGC) maximum likelihood detection (MLD) and correlation matrix detection (CMD) are derived. When a quasi-static fading and weak turbulence channel model are considered, simulation results show that whether the channel state information (CSI) is known or not, the coding sys- tem demonstrates more significant performance of the symbol error rate (SER) than the uncoding. In other words, transmitting diversity can be achieved while conveying the information only through the time delays of the modulated signals transmitted from different antennas. CMD has almost the same effect of signal combining with maximal ratio combining (MRC). However, when the channel correlation increases, SER performance of the coding 2×2 system de- grades significantly.
文摘The intricate interplay between neurotransmitter systems,neural circuits,and neuroendocrine pathways underpins brain function and dysfunction in neurological and psychiatric disorders.This review synthesizes contemporary advances in neuropharmacology,focusing on dopaminergic,serotonergic,glutamatergic,and GABAergic systems,and their roles in regulating motor control,cognition,emotion,and stress responses.Dopaminergic pathways,including the nigrostriatal,mesolimbic,and mesocortical circuits,are explored in the context of Parkinson’s disease,schizophrenia,and addiction,with emphasis on pharmacological agents such as L-DOPA,antipsychotics,and amphetamines.Serotonergic modulation through SSRIs and psychedelics is examined for its impact on mood and neuroplasticity,while glutamatergic and GABAergic systems are discussed in relation to synaptic plasticity,excitotoxicity,and therapeutic innovations like ketamine and benzodiazepines.The neuroendocrine system,particularly the hypothalamic-pituitary-adrenal(HPA)axis,is highlighted for its role in stress-related disorders and interactions with neurotransmitter networks.Despite progress,significant challenges persist,including translational gaps between preclinical models and human trials,species-specifi c receptor disparities,and ethical dilemmas surrounding cognitive enhancers and genetic manipulation.Emerging frontiers such as nanotechnology-enabled drug delivery,optogenetics,and gut-brain axis modulation are reviewed as transformative approaches to overcome these barriers.Personalized medicine,integrating neuroimaging biomarkers and pharmacogenomics,promises to tailor therapies to individual neural and genetic profi les,while biased agonists and closed-loop systems exemplify the shift toward circuit-specifi c interventions.Ethical considerations,including equitable access to advanced therapies and responsible innovation,are underscored as critical to ensuring societal benefi t.By harmonizing molecular precision with systems neuroscience,this review advocates for interdisciplinary strategies to advance neuropharmacology,ultimately aiming to restore dynamic neural and neuroendocrine homeostasis in health and disease.
文摘This article presents views on the future development of data science,with a particular focus on its importance to artificial intel-ligence(AI).After discussing the challenges of data science,it elu-cidates a possible approach to tackle these challenges by clarifying the logic and principles of data related to the multi-level complex-ity of the world.Finally,urgently required actions are briefly outlined.
文摘The ability to accurately simulate the time evolu-tion of quantum systems stands as a cornerstone of modern molecular science.It provides the essential mechanistic bridge between a system’s microscopic structure and its macroscopic function,a challenge first envisioned by Feynman.The central difficulty,and the unifying theme of this Special Topic,is the problem of“complexity”:a multifaceted challenge arising from the interplay of strongly coupled electronic and vibrational degrees of freedom,quantum statistics,and the non-trivial,often non-Markovian,memory effects exerted by a surrounding environment.
基金supported by the National Natural Science Foundation of China(62303273,62373226)the National Research Foundation,Singapore through the Medium Sized Center for Advanced Robotics Technology Innovation(WP2.7)
文摘Dear Editor,The letter deals with the distributed state and fault estimation of the whole physical layer for cyber-physical systems(CPSs) when the cyber layer suffers from DoS attacks. With the advancement of embedded computing, communication and related hardware technologies, CPSs have attracted extensive attention and have been widely used in power system, traffic network, refrigeration system and other fields.
基金supported by the National Natural Science Foundation of China(Nos.42122012,U2444208)the Inner Mongolia Academician Project(No.2022-TZH03)the Fundamental Research Funds for the Central Universities(No.2652023001)。
文摘The patterns of metal distribution and alteration zonation in magmatic-hydrothermal systems primarily focus on porphyry deposit and other closely associated types,such as skarn,epithermal and distal vein deposits(e.g.,Zheng,2022;Hutchison et al.,2020;Cooke et al.,2011;Hedenquist et al.,1998).
文摘Objectives:Recently,the global esports industry has experienced remarkable growth,leading to an expansion in the scale and influence of professional player communities.However,despite this outward growth,systems to protect players’mental health remain inadequate.Comprehensive analysis of structural risk factors,including performance pressure,public evaluation,and career instability,remains insufficient.This study,aimed to explore stressors encountered by esports athletes,coping strategies,and the role of social support systems in safeguarding mental health.Using the transactional model of stress and coping,the job demands–resources model,and social support theory,the study adopts an integrated perspective to examine challenges faced by athletes in the competitive esports environment.Methods:A qualitative case study was conducted involving in-depth interviews and nonparticipant observations with 11 esports athletes who competed at national or international levels,as well as two team managers.Thematic analysis identified recurring patterns in the data,and credibility was ensured through triangulation and cross-review among researchers.Results:Esports athletes experience multiple interacting stressors,including performance demands,emotional strain duringmatches,and continuous evaluation on socialmedia.In response,they employed coping strategies—problem-focused,emotion-focused,and avoidance-based,which provided temporary relief but often led to burnout and self-regulation failure owing to absence of support systems.Social support networks had ambivalent effects:while offering comfort,they also intensified pressure through negative feedback and high expectations from fans and online communities.Conclusion:The findings show that mental health issues among esports athletes are not only related to individual factors but are closely linked to performance-driven structures,competitive environments,and social relationships.This study integrates the transactional model of stress and coping,the JobDemands–Resourcesmodel,and social support theoryto provide comprehensive analysis.It also offers practical recommendations,including psychological counseling,emotional labor programs,and improved communication with families and fan communities.