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Predicting acceleration response spectrum from P-wave arrivals via a long short-term memory neural network 认领 引用 被引量：2
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作者 Dai Haozhen Zhou Yueyong +3 位作者 Li Shanyou Wei Yongxiang Liu Heyi Song Jindong 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2026年第2期333-345,共13页
An on-site earthquake early warning model utilizing a long short-term memory(LSTM)neural network is proposed,diverging from traditional methods by focusing on acceleration response spectrum Sa,the ground motion intens... An on-site earthquake early warning model utilizing a long short-term memory(LSTM)neural network is proposed,diverging from traditional methods by focusing on acceleration response spectrum Sa,the ground motion intensity measure correlated with structural responses.A three-channel acceleration waveform is taken as the model input,and an acceleration response spectrum serves as output.The model is trained using strong motion acceleration data acquired from Japan's K-NET network.On the test set,the mean squared error(MSE)of the predictions yielded by the proposed model decreases as the input time window increases.In the temporal window spanning from 1-10 s,an MSE reduction of 72.35%is observed.The MSE is 1.92×10-4g 10 s after the P-wave is triggered.When subjected to generalization testing with cross-regional and cross-instrument-type Chinese intensity meter data,the model still exhibits the same trend as that observed on the test set.The MSE decreases by 74.16%10 s after the P-wave is triggered(compared to the value obtained 1 s after the P-wave is triggered).The MSE is 1.93×10-4g 10 s after the P-wave is triggered in the cross-domain dataset.The results demonstrate that the proposed model exhibits good generalization performance. 展开更多
关键词 earthquake early warning response spectrum long short-term memory
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Evergreen vs.deciduous species:Whose water use efficiency can influence the plant trait spectrum in the karst evergreen-deciduous mixed broad-leaved forests? 认领 引用
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作者 Xuerong Shao Yingqun Chen +7 位作者 Shuo Wang Yi Jiang Lipeng Zang Guangqi Zhang Qingfu Liu Danmei Chen Fangjun Ding Mingzhen Sui 《Forest Ecosystems》 SCIE CAS CSCD 2026年第2期400-411,共12页
Unraveling the drivers of the plant trait spectrum is crucial for explaining species coexistence,especially in biodiverse ecosystems.Focusing on the Maolan Nature Reserve,a typical karst evergreen-deciduous mixed fore... Unraveling the drivers of the plant trait spectrum is crucial for explaining species coexistence,especially in biodiverse ecosystems.Focusing on the Maolan Nature Reserve,a typical karst evergreen-deciduous mixed forest,this study examined the contributions of water use efficiency(WUE)differences between those species to their trait spectra in 30 plots by measuring the plant functional traits.WUE characterization based on stable carbon isotopes and modeling revealed significant WUE and plant trait spectrum differences between evergreen and deciduous trees.In addition,their WUE could significantly influence their functional traits,functional diversity,and leaf economic spectrum.Moreover,the WUE of deciduous species played a more important role in influencing the plant trait spectrum compared to evergreen species.Specifically,compared to evergreen trees,deciduous trees contributed more to the functional diversity,mainly by altering the niche overlap.The findings demonstrated the key role of deciduous species in ecosystem functioning and highlighted the importance of niche differentiation for species coexistence in karst forests. 展开更多
关键词 Carbon isotope Water use efficiency(WUE) Plant trait spectrum Leaf economic spectrum(LES) Karst forests
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Super-resolution reconstruction of UAV-borne gamma-ray spectrum images based on Real-ESRGAN algorithm 认领 引用
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作者 Xin Wang Yuan Yuan +4 位作者 Xuan Zhao Guang-Hao Luo Qi-Qiao Wei He-Xi Wu Chao Xiong 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第2期42-54,共13页
Unmanned aerial vehicle(UAV)-borne gamma-ray spectrum survey plays a crucial role in geological mapping,radioactive mineral exploration,and environmental monitoring.However,raw data are often compromised by flight and... Unmanned aerial vehicle(UAV)-borne gamma-ray spectrum survey plays a crucial role in geological mapping,radioactive mineral exploration,and environmental monitoring.However,raw data are often compromised by flight and instrument background noise,as well as detector resolution limitations,which affect the accuracy of geological interpretations.This study aims to explore the application of the Real-ESRGAN algorithm in the super-resolution reconstruction of UAV-borne gamma-ray spectrum images to enhance spatial resolution and the quality of geological feature visualization.We conducted super-resolution reconstruction experiments with 2×,4×and 6×magnification using the Real-ESRGAN algorithm,comparing the results with three other mainstream algorithms(SRCNN,SRGAN,FSRCNN)to verify the superiority in image quality.The experimental results indicate that Real-ESRGAN achieved a structural similarity index(SSIM)value of 0.950 at 2×magnification,significantly higher than the other algorithms,demonstrating its advantage in detail preservation.Furthermore,Real-ESRGAN effectively reduced ringing and overshoot artifacts,enhancing the clarity of geological structures and mineral deposit sites,thus providing high-quality visual information for geological exploration. 展开更多
关键词 UAV-borne gamma-ray spectrum Super-resolution reconstruction Real-ESRGAN Image processing
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Nose-to-brain administration of cannabidiol-loaded polymeric micelles improves the core behavioral symptoms of autism spectrum disorder 认领 引用
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作者 Rania Awad Shlomit Aga-Mizrachi +3 位作者 Inon Maoz Lilach Simchi Avi Avital Alejandro Sosnik 《Bioactive Materials》 SCIE CSCD 2026年第8期831-845,共15页
Neurodevelopmental disorders including autism spectrum disorder(ASD)affect 5.9%of the global population.Research shows the potential therapeutic use of cannabidiol(CBD)to treat different neurodevelopmental dis-orders,... Neurodevelopmental disorders including autism spectrum disorder(ASD)affect 5.9%of the global population.Research shows the potential therapeutic use of cannabidiol(CBD)to treat different neurodevelopmental dis-orders,including ASD.Intranasal drug delivery(i.n.)is a non-invasive and painless administration route that enhances drug bioavailability in the brain bypassing the blood-brain barrier.Various polymeric nanoparticles have been investigated for i.n.delivery with different success levels.In this study,we developed and charac-terized polymeric micelles of the poly(ethylene oxide)-b-poly(propylene oxide)block copolymer Pluronic®F127 loaded with 25%w/w CBD(based on solid weight)for nose-to-brain delivery in ASD.CBD-loaded polymeric micelles display a hydrodynamic diameter of 41±1 nm by Intensity and 23±1 nm by Number,as measured by dynamic light scattering,and very good compatibility and permeability in the human nasal septum cell line RPMI 2650,an in vitro model of the nasal epithelium.The accumulation of CBD-loaded polymeric micelles adminis-tered intranasally in the brain of ASD-like rats is confirmed by bioimaging.The CBD pharmacokinetics upon the i.n.(dose of 5 mg/kg)and oral(15 mg/kg)administration of the loaded polymeric micelles shows a 27.8%in-crease of the CBD concentration in the brain of ASD-like rats 20 min after i.n.administration,despite the 3-fold decrease in the dose.Finally,the efficacy of this nanoformulation to improve the core symptoms of ASD is demonstrated in behavioral studies in a behavioral model of the disorder in rats. 展开更多
关键词 Autism spectrum disorder Cannabidiol-loaded polymeric micelles Nose-to-brain drug delivery Social cooperation
Secure and robust resource allocation for UAV-assisted anti-jamming spectrum sharing under uncertain jamming in airborne maneuvering networks 认领 引用
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作者 Rui DING Haotian QUAN +1 位作者 Zhijie ZENG Fuhui ZHOU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第5期111-121,共11页
Airborne Maneuvering Network(AMN)has attracted great attention in diverse practical scenarios.Low-altitude maneuvering UAV plays as the operational backbone of AMN to promote the development of an efficient,secure,and... Airborne Maneuvering Network(AMN)has attracted great attention in diverse practical scenarios.Low-altitude maneuvering UAV plays as the operational backbone of AMN to promote the development of an efficient,secure,and low-latency AMN by providing new airborne wireless nerve tracts.However,the widespread adoption of AMNs witnesses a drastic increase of mobile users and data-intensive applications,which makes it suffer from the intense spectrum competition.Spectrum sharing shows promise in alleviating the severe spectrum scarcity of AMNs.Moreover,due to the broadcast nature of wireless channels and the increasing probability of the line-of-sight transmission,the AMN is vulnerable to malicious jamming,especially encountering the coupled uncertainty and dynamic jamming.To solve these problems,UAV-assisted antijamming spectrum sharing in AMNs is investigated.We propose a joint space-power-frequency domain optimization approach to simultaneously mitigate both external malicious jamming and internal sharing interference.The sum rate maximization of the secondary network is studied by jointly optimizing the UAV transmit power,sub-band allocation,and trajectory.To tackle the formulated intractable non-convex problem,we propose a computationally efficient iterative algorithm based on alternating optimization,integrating the S-procedure to handle bounded uncertainties and the successive convex approximation to obtain near-optimal convex solutions.Extensive simulation results show that our proposed scheme can significantly increase the sum transmission rate.Moreover,it is shown that our proposed scheme is the best robust among all benchmark schemes against jammer location and power uncertainties,confirming the practicality for the next-generation UAV based airborne networks. 展开更多
关键词 Airborne maneuvering networks Anti-jamming Resource allocation Spectrum management UAV communication
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Enhanced atomic localization and precision control in a four-level atomic medium via transmission spectrum 认领 引用
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作者 Muhammad Idrees Fatima Ghulam Kakepoto Zareen A Khan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2026年第1期51-60,共10页
In this article,we introduce a new theoretical approach to improve the accuracy of two-dimensional(2D)atomic localization within a tripod-type,four-level atomic system by analyzing its transmission spectrum.In this me... In this article,we introduce a new theoretical approach to improve the accuracy of two-dimensional(2D)atomic localization within a tripod-type,four-level atomic system by analyzing its transmission spectrum.In this method,the atom interacts with two orthogonal standing-wave fields and a weak probe field.By examining how the weak probe field passes through the system,we can determine the atom position.Our analysis reveals the presence of both double and sharply defined single localized peaks in the transmission spectrum,which correspond to specific positions of the atom.Importantly,we achieve ultra-high-resolution atomic localization with accuracy confined to a region smaller thanλ/32×λ/32.This level of precision is a significant improvement compared to earlier methods,which had lower localization accuracy.The increased precision is due to the complex interaction between the atom and the carefully controlled standing-wave and probe fields,which allows for precise control over the atom’s position.The implications of this work are significant,especially for applications like nano-lithography,where precise atomic placement is essential,and for laser cooling technologies,where better atomic localization could lead to more effective cooling processes and improved manipulation of atomic states. 展开更多
关键词 atomic localization transmission spectrum standing-wave fields ultra-high resolution nano-lithography
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Measurement and calculation of neutron transmission spectra through 238U irradiated by a broad-spectrum neutron field 认领 引用
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作者 Hui Sun Xin Zhang +10 位作者 Zhi‑Qiang Chen Rui Han Bo Yang Shakhboz Khasanov Pei‑Yan Zhang Guo‑Yu Tian Bing‑Yan Liu Fu‑Dong Shi Ze‑Kun Zhang Qin Li Peng Luo 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第8期243-251,共9页
The neutron transmission spectrum through a high-purity238 U slab(dimensions:100 mm×100 mm×20 mm)irradiated by a broad-spectrum neutron field was measured at 0°using the time-of-flight(TOF)method.The... The neutron transmission spectrum through a high-purity238 U slab(dimensions:100 mm×100 mm×20 mm)irradiated by a broad-spectrum neutron field was measured at 0°using the time-of-flight(TOF)method.The experiment was carried out at the Radioactive Ion Beam Line of the Heavy Ion Research Facility in Lanzhou at the Institute of Modern Physics,Chinese Academy of Sciences.Broad-spectrum neutrons were generated by bombarding a tungsten target with 80.5 MeV/u12 C ions.GEANT4 calculations were performed under the same experimental conditions by combining the INCL++,BIC,and BERT physics models with the evaluated nuclear data libraries ENDF/B-VIII.0,JEFF-3.3,and JENDL-4.0.The calculations reproduce the measured spectrum reasonably well over most of the investigated energy range;however,they overestimate the data below 10 MeV and tend to underestimate the measured yield above 70 MeV.The present results provide benchmark information for validating neutron-transport simulations relevant to accelerator-driven systems. 展开更多
关键词 Neutron transmission spectrum 238U Broad-spectrum neutrons GEANT4
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Near-Surface Q-Factor Estimation Using a Non-Gaussian Energy Spectrum 认领 引用
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作者 Ze-lin Li Jiang-nan Tong +2 位作者 Ya-nan Jiang Tong Chen Guo-fa Li 《Applied Geophysics》 SCIE CSCD 2026年第2期735-749,871,共15页
Accurate near-surface Q-factor estimation is essential for attenuation compensation,high-resolution imaging,and shallow-structure characterization.However,the reliability of conventional methods deteriorates in strong... Accurate near-surface Q-factor estimation is essential for attenuation compensation,high-resolution imaging,and shallow-structure characterization.However,the reliability of conventional methods deteriorates in strongly attenuating media because they commonly rely on weak-attenuation approximations or Gaussian spectrum assumptions.This paper proposes a near-surface Q-factor estimation method based on non-Gaussian energy spectrum.The proposed method has three main advantages.First,it is formulated on the energy spectrum rather than the amplitude spectrum,which improves spectral concentration and numerical stability.Second,it replaces the Gaussian assumption with an exponential frequency-weighted energy-spectrum model,thereby allowing for non-Gaussian spectrum shapes.Third,it employs an exact absorption coeffi cient derived from the complex wavenumber-Q relation,thus avoiding the weak-attenuation approximation in low-Q media.Synthetic cross-hole experiments show that the proposed method provides more accurate and more stable estimates than the spectral ratio and centroid frequency shift methods,especially under strong attenuation and noisy conditions.Field downhole data further demonstrate that the method can identify attenuation responses and support layered Q characterization in the near surface. 展开更多
关键词 near-surface attenuation Q-factor estimation energy spectrum centroid frequency shift
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ARQ–UCB:A Reinforcement-Learning Framework for Reliability-Aware and Efficient Spectrum Access in Vehicular IoT 认领 引用
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作者 Adeel Iqbal Tahir Khurshaid +2 位作者 Syed Abdul Mannan Kirmani Mohammad Arif Muhammad Faisal Siddiqui 《Computers, Materials & Continua》 SCIE EI 2026年第5期1524-1545,共22页
Vehicular Internet ofThings(V-IoT)networks need intelligent and adaptive spectrum access methods for ensuring ultra-reliable and low-latency communication(URLLC)in highly dynamic environments.Traditional reinforcement... Vehicular Internet ofThings(V-IoT)networks need intelligent and adaptive spectrum access methods for ensuring ultra-reliable and low-latency communication(URLLC)in highly dynamic environments.Traditional reinforcement learning(RL)-based algorithms,such as Q-Learning and Double Q-Learning,are often characterized by unstable convergence and inefficient exploration in the presence of stochastic vehicular traffic and interference.This paper proposes Adaptive Reinforcement Q-learning with Upper Confidence Bound(ARQ-UCB),a lightweight and reliability-aware RL framework,which explicitly reduces interruption and blocking probabilities while improving throughput and delay across diverse vehicular traffic conditions.This proposed ARQ-UCB algorithm extends the basic Q-updates with an exploration confidence term able to dynamically balance exploration and exploitation based on uncertainty estimates,hence allowing faster convergence in case of bursty vehicular traffic.A comprehensive simulation framework evaluates throughput,delay,fairness,energy efficiency,and computational complexity in several V-IoT scenarios.Obtained results indicate that ARQ–UCB attains substantial gains in terms of throughput,fairness,and blocking/delay probabilities while retaining sub-20μs decision latency and O(1)complexity per decision,thus validating real-time feasibility for reliable spectrum access in 5G and beyond V-IoT networks. 展开更多
关键词 V-IoT RL Q-Learning upper confidence bound spectrum access URLLC 5G/6G
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Pan-KRAS inhibition:unlocking broad-spectrum targeted therapy for KRAS-mutant cancers 认领 引用
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作者 Juanjuan Feng Xuanzheng Xiao +2 位作者 Zhengke Lian Ao Zhang Xiufeng Pang 《Cancer Biology & Medicine》 SCIE CAS CSCD 2026年第2期162-168,共7页
KRAS is a critical proto-oncogene and molecular switch that is frequently mutated in human cancers.Oncogenic mutations,primarily at codons 12,13,and 61,lock KRAS into a GTPbound active state,thus resulting in constitu... KRAS is a critical proto-oncogene and molecular switch that is frequently mutated in human cancers.Oncogenic mutations,primarily at codons 12,13,and 61,lock KRAS into a GTPbound active state,thus resulting in constitutive signaling through downstream effectors such as RAF and phosphoinositide 3-kinase(PI3K)1.These alterations are highly prevalent in pancreatic cancer,colorectal cancer(CRC),and non-small cell lung cancer(NSCLC),and they drive tumor initiation,progression,and therapy resistance. 展开更多
关键词 constitutive signaling downstream effectors broad spectrum targeted therapy proto oncogene pan kras inhibition kras mutant cancers molecular switch therapy resistance
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Serum folate and brain-derived neurotrophic factor in pediatric autism spectrum disorder and their predictive role in illness severity 认领 引用
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作者 Li-Bin Chen Xiao-Qin Xu Yan-Hui Chen 《World Journal of Psychiatry》 SCIE 2026年第3期89-98,共10页
BACKGROUND Autism spectrum disorder(ASD)involves social and neurological impairment,and affected individuals have an elevated risk of bullying.AIM To clarify serum folate(SF)and brain-derived neurotrophic factor(BDNF)... BACKGROUND Autism spectrum disorder(ASD)involves social and neurological impairment,and affected individuals have an elevated risk of bullying.AIM To clarify serum folate(SF)and brain-derived neurotrophic factor(BDNF)expression in ASD-affected children and evaluate their prediction value for illness severity.METHODS From February 2023 to February 2025,53 ASD-affected children and 50 healthy controls visiting Fuzhou University Affiliated Provincial Hospital were enrolled as the research and control groups,respectively.SF and BDNF levels were measured in all children.The Childhood Autism Rating Scale(CARS)was used to assess ASD symptom severity.In ASD cases,SF and BDNF expression differences were compared across illness-severity subgroups and before versus after treatment.Pearson r was used to assess correlations between SF/BDNF and CARS in the research group.Receiver operating characteristic(ROC)curves were used to assess their predictive value for ASD severity.Univariate and multivariate binary Logistic models were used to identify ASD progression determinants.RESULTS ASD children showed significantly lower SF and higher BDNF higher than controls.Severe cases had lower SF and higher BDNF than mild-to-moderate cases.SF correlated inversely with the CARS score,whereas BDNF correlated positively.For predicting ASD severity,the area under the ROC curve(AUC)of SF and BDNF was 0.700-0.750,and their combined use increased the AUC to 0.823.Both markers were confirmed to be independent determinants of ASD aggravation.CONCLUSION SF is down-regulated and BDNF is up-regulated in ASD-affected children,SF correlates negatively with ASD severity and BDNF correlates positively.Low SF and high BDNF are risk factors for ASD deterioration in children. 展开更多
关键词 Serum folate Brain-derived neurotrophic factor Autism spectrum disorder Children Illness severity Receiver operating characteristic curve
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Dynamic characterization of pathological and functional deterioration in a mouse model of optic neuritis related to neuromyelitis optica spectrum disorder 认领 引用
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作者 Xiayin Yang Shi-Qi Yao +1 位作者 Henry Ho-Lung Chan Shaoying Tan 《Neural Regeneration Research》 SCIE CAS CSCD 2026年第8期3870-3880,共11页
Neuromyelitis optica spectrum disorder-related optic neuritis involves various cellular responses to inflammation and degeneration.In most patients,the primary mechanism underlying neuromyelitis optica spectrum disord... Neuromyelitis optica spectrum disorder-related optic neuritis involves various cellular responses to inflammation and degeneration.In most patients,the primary mechanism underlying neuromyelitis optica spectrum disorder-related optic neuritis is the interaction of aquaporin-4 antibodies with the aquaporin-4 protein present on astrocytes within posterior optic nerve.This binding subsequently initiates a cascade of events leading to secondary demyelination of the optic nerve,ultimately culminating in optic nerve degeneration.Earlier studies on this disorder primarily used systemic-induced animal models,which often require prior activation of a systemic immune response.This can result in primary demyelination of the optic nerve,complicating the interpretation of experimental results.Such methodologies hinder the ability to isolate immune responses triggered by specific antibodies.Additionally,the lack of a detailed profile of disease progression over time limits our capacity to identify potential intervention windows.Therefore,constructing a targeted optic neuritis animal model induced by specific antibodies and elucidate the disease progression arecrucial for exploring the mechanisms underlying neuromyelitis optica spectrum disorder-related optic neuritis.In this study,specific antibodies against aquaporin-4 were precisely injected into the retrobulbar optic nerve of mice to induce a targeted inflammatory response in the posterior optic nerve,resulting in a more representative mouse model of neuromyelitis optica spectrum disorder-related optic neuritis than current models.The progression of the disease was then dynamically observed from both histological and functional perspectives over the course of 1 month following the induction of inflammation.By the first week,astrocytes were damaged,as evidenced by the loss of aquaporin-4 and glial fibrillary acidic protein,the activation of microglia,and the upregulation of microglia-related cytokines,including tumor necrosis factor,interleukin-6,interleukin-1β,C-X-C motif ligand 10,and brain-derived neurotrophic factor.Starting from the second week,there were signs of optic nerve demyelination and significant damage to axonal fibers and retinal ganglion cell bodies.Visual-evoked potentials and dark adaptation threshold responses in electroretinogram both indicated dysfunction in the visual pathway and retina,while optical coherence tomography revealed thinning of the retinal nerve fiber layer in live mice.In summary,in this study we conducted a dynamic exploration of the occurrence and progression of neuromyelitis optica spectrum disorder-related optic neuritis triggered by specific antibodies.Our results show pathological changes at various stages and correlate histological and molecular alterations with in vivo structural and functional deterioration.The findings from this study lay an important foundation for further research on neuromyelitis optica spectrum disorder-related optic neuritis. 展开更多
关键词 animal model aquaporin-4 immunoglobulin G dynamic profile electroretinogram functional deterioration in vivo retinal structural scan neuromyelitis optica spectrum disorder-related optic neuritis optic neuritis pathology visual-evoked potential
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3D Spectrum Mapping and Reconstruction Under Multi-Radiation Source Scenarios 认领 引用 被引量：1
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作者 Wang Jie Lin Zhipeng +5 位作者 Zhu Qiuming Wu Qihui Lan Tianxu Zhao Yi Bai Yunpeng Zhong Weizhi 《China Communications》 SCIE EI CSCD 2026年第2期20-34,共15页
Spectrum map construction,which is crucial in cognitive radio(CR)system,visualizes the invisible space of the electromagnetic spectrum for spectrum-resource management and allocation.Traditional reconstruction methods... Spectrum map construction,which is crucial in cognitive radio(CR)system,visualizes the invisible space of the electromagnetic spectrum for spectrum-resource management and allocation.Traditional reconstruction methods are generally for twodimensional(2D)spectrum map and driven by abundant sampling data.In this paper,we propose a data-model-knowledge-driven reconstruction scheme to construct the three-dimensional(3D)spectrum map under multi-radiation source scenarios.We firstly design a maximum and minimum path loss difference(MMPLD)clustering algorithm to detect the number of radiation sources in a 3D space.Then,we develop a joint location-power estimation method based on the heuristic population evolutionary optimization algorithm.Considering the variation of electromagnetic environment,we self-learn the path loss(PL)model based on the sampling data.Finally,the 3D spectrum is reconstructed according to the self-learned PL model and the extracted knowledge of radiation sources.Simulations show that the proposed 3D spectrum map reconstruction scheme not only has splendid adaptability to the environment,but also achieves high spectrum construction accuracy even when the sampling rate is very low. 展开更多
关键词 cognitive radio map reconstruction path loss model radiation source 3D spectrum map
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Effects of light spectrum on survival rate,growth performance,and oxidative stress in juvenile swimming crab(Portunus trituberculatus) 认领 引用
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作者 Lulu ZHU Shuai ZHANG +7 位作者 Shujian CHEN Changbin SONG Yangfang YE Ronghua LI Weiwei SONG Changkao MU Chunlin WANG Ce SHI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2026年第4期1774-1788,共15页
The effects of seven different light spectra—white(full spectrum),violet(400 nm),blue(425 nm),cyan(510 nm),green(525 nm),yellow(598 nm),and red(638 nm)—on the survival,growth,molting,respiratory metabolism,antioxida... The effects of seven different light spectra—white(full spectrum),violet(400 nm),blue(425 nm),cyan(510 nm),green(525 nm),yellow(598 nm),and red(638 nm)—on the survival,growth,molting,respiratory metabolism,antioxidant capacity,and stress responses of juvenile swimming crabs were investigated,and to further explore the molecular mechanisms through which light spectra influence these physiological processes,transcriptome analysis was conducted.Results indicate that cyan light enhanced the growth performance of swimming crabs,with greater mean values of specific growth rate(SGR),weight gain rate(WGR),and molting frequency than those of the other groups.Additionally,the oxygen consumption rate(OCR)and ammonia excretion rate(AER)of crabs in yellow group(P<0.05)were significantly increased.Swimming crabs experienced heightened oxidative stress,as antioxidant enzymes were unable to effectively neutralize excessive lipid peroxides under red light.Furthermore,the expression of(retinoid X receptor)rxr and(ecdysone-induced protein 75)e75 genes in juvenile swimming crabs under cyan light were significantly elevated(P<0.05),promoting molting.Our further investigation into the potential molecular mechanisms of these effects revealed the structural molecule activity,cuticle composition,and ribosomal function as potential regulators of molting,and the close ties of DNA replication and base excision repair pathways with oxidative stress responses.Our findings suggest that cyan light is beneficial for enhancing the growth and overall well-being of juvenile swimming crabs. 展开更多
关键词 swimming crab light spectrum molting antioxidant capacity apoptosis
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A novel digital cousin based intelligent resource allocation scheme for secure low-altitude UAV spectrum sharing in AMN 认领 引用
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作者 Zhijie ZENG Rui DING +3 位作者 Yuhang WU Yihe DIAO Fuhui ZHOU Qihui WU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第5期122-131,共10页
The Airborne Maneuvering Network(AMN)is becoming an emerging field due to its wide-area coverage and localized service enhancement characteristics,in which Low-altitude Unmanned Aerial Vehicles(LUAVs)interact directly... The Airborne Maneuvering Network(AMN)is becoming an emerging field due to its wide-area coverage and localized service enhancement characteristics,in which Low-altitude Unmanned Aerial Vehicles(LUAVs)interact directly with ground-based devices after receiving commands from upper layers.However,the exponential increase in communication devices has led to a severe scarcity of spectrum for LUAVs.Furthermore,LUAVs communications are highly susceptible to interception by Eavesdroppers(Eves)due to the open characteristic of the wireless environment.Therefore,a secure spectrum sharing at LUAVs layer in AMN is studied.Moreover,to address the issue that the dynamic and heterogeneous characteristic of wireless environments presents significant challenges for resource allocation,a Digital Cousin based Q-learning(DCQ)method is proposed.Specifically,the original Probability Transition Matrix(PTM)obtained from sampling in the environment is transformed using the co-link method to obtain multiple virtual environments.Multiple agents are trained in parallel in multiple environments and the training results are fused to obtain the final Q function to output the policy of the original environment.The simulation results demonstrate that the proposed scheme can achieve more robust policies and faster convergence compared to conventional Deep Reinforcement Learning(DRL)methods. 展开更多
关键词 Digital cousin Eavesdropping LUAVs Spectrum sharing Resource allocation
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Photonic instantaneous spectrum analysis with massive frequency bins 认领 引用
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作者 XUE LAN SHILONG CHEN +5 位作者 HAOYAN XU ZIHANG WANG FEIFEI YIN KUN XU MING LI YITANG DAI 《Photonics Research》 SCIE EI CAS CSCD 2026年第7期2783-2792,共10页
Broadband and gap-free analysis of the time-frequency evolution of non-stationary signals is critical for emerging wireless networks and integrated sensing and communication applications.In particular,the photonic app... Broadband and gap-free analysis of the time-frequency evolution of non-stationary signals is critical for emerging wireless networks and integrated sensing and communication applications.In particular,the photonic approach based on frequency-to-time mapping(FTM)has emerged as a promising solution for wideband gap-free instantaneous spectrum analysis(ISA).However,although approaches such as time-lens-based schemes have demonstrated nanosecond-scale frame rate and gigahertz-level bandwidth,they still face significant limitations,including severe bandwidth expansion before photodetection and excessive dispersion requirement,making the acquisition of massive frequency bins impractical.Here,we present a dispersion-efficient photonics scheme to overcome these limitations.By employing dual optical frequency combs(OFCs),it efficiently reduces the dispersion requirement and mitigates the output bandwidth expansion.In addition,by introducing the channelization technique,the parallel processing further extends the signal bandwidth and multiplicatively increases the number of frequency bins.In this work,we demonstrate an ISA architecture with a bandwidth of 20 GHz,a frequency resolution of 78.125 MHz,and a time resolution of 12.8 ns,yielding 256 frequency bins.In experiment,the spectrum is channelized into 16 frequency channels,with each requiring only a 2.5-GHz-bandwidth balanced photodetector(BPD).Remarkably,to achieve the demonstrated bandwidth and resolution,our architecture reduces the dispersion requirement of traditional FTM systems by a factor of 20,while avoiding the use of a 40 GHz high-speed photodetector by employing 2.5 GHz BPDs. 展开更多
关键词 channelization technique photonic approach non stationary signals photonic spectrum analysis dispersion efficiency spectrum analysis isa howeveralthough frequency time mapping dual optical frequency combs
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Comparative screening accuracy of the Modified Checklist for Autism in Toddlers,Revised with Follow-Up(M-Chat-R/F)for early autism spectrum disorder:a systematic review 认领 引用
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作者 Aaron Siong Fatt Tsen Mohammad Azri Bantalani +2 位作者 Muhammad Nazrin Ab Rahim Siti Zuraina Ain Amat Khalid Mokti 《Family Medicine and Community Health》 2026年第2期97-104,共8页
Objective Early screening for autism spectrum disorder(ASD)is critical for timely intervention,making the Modified Checklist for Autism in Toddlers,Revised with Follow-Up(M-CHAT-R/F)a widely adopted tool globally.Howe... Objective Early screening for autism spectrum disorder(ASD)is critical for timely intervention,making the Modified Checklist for Autism in Toddlers,Revised with Follow-Up(M-CHAT-R/F)a widely adopted tool globally.However,a recent systematic synthesis of its comparative accuracy is lacking.This review aimed to evaluate the screening accuracy of the M-CHAT-R/F against other ASD screening instruments.Design A systematic review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.A narrative synthesis was employed to integrate findings across diverse study designs and methodological quality was assessed using the Joanna Briggs Institute checklist.Eligibility criteria Peer-reviewed,English-language observational studies published between January 2020 and October 2025 that compared the accuracy metrics of the M-CHAT-R/F with alternative screening tools.Information sources Scopus,PubMed,ScienceDirect and ProQuest.Results From 172 identified articles,six high-quality studies encompassing 12633 participants aged 12–48 months were analysed.The synthesis revealed a complex performance profile for the M-CHAT-R/F.While its sensitivity for detecting potential cases was highly inconsistent,its negative predictive value remained consistently high,reliably identifying children who screened negative.Conversely,the tool demonstrated variable specificity and a persistently low positive predictive value,indicating a substantial false-positive burden and reduced confidence in positive results.Furthermore,the M-CHAT-R/F’s accuracy was highly age-dependent,with performance degrading outside the optimal 16–30-month window compared with other specialised tools.Conclusions The M-CHAT-R/F may not be an optimal instrument in every clinical setting.Its clinical utility may be limited by variable sensitivity and a lower positive predictive value,potentially creating a higher false-positive burden.Clinicians and health systems should consider adopting age-specific,tiered screening protocols to improve diagnostic efficiency and better allocate intervention resources. 展开更多
关键词 Screening Accuracy timely interventionmaking Modified Checklist Autism Toddlers Revised Follow up systematic review autism spectrum disorder asd systematic synthesis Autism Spectrum Disorder modified checklist
Assessing the resource dynamics of economic fishes in the Dachen Island Marine Ranch in the East China Sea based on size spectrum model 认领 引用
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作者 Jiaju ZHANG Yuru LI +4 位作者 Yajing CHEN Jiadi YING Xiaopeng CHENG Zhenhua WANG Yingbin WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2026年第2期904-919,共16页
Marine ranch is a novel paradigm in the transformation of traditional fisheries,which embodies a modern and high-tech approach to increasing marine fishery production and enables the sustainable and efficient exploita... Marine ranch is a novel paradigm in the transformation of traditional fisheries,which embodies a modern and high-tech approach to increasing marine fishery production and enables the sustainable and efficient exploitation of marine resources.After several decades of development,the industrial model of marine ranch has matured.However,in several developing countries,subsequent management and evaluation remain inadequate.In this study,the Dachen Island Marine Ranch in the East China Sea was used as a case to explore two fishery management strategies.A multi-species size spectrum model(MSSM)was established for the Dachen Island Marine Ranch to simulate fish community dynamics.While considering interspecific interactions,the effectiveness of two management strategies was assessed:(1)altering fishing mortality;and(2)increasing cod-end mesh size.The findings indicate that the change in the fishing mortality of large predators can induce trophic cascade effects,and the large predators have the greatest impact on community structure.In scenarios that simulate fishing mortality for multiple species,competition is shown between two species occupying similar ecological niches.An increase in cod-end mesh size can be observed to decrease bycatch while positively impacting community structure.Our findings suggest that fisheries management reforms should consider the effects of management changes on the entire ecosystem(including environment and biodiversity),rather than concentrating solely on the long-term yield of fish harvests.A stable ecosystem can yield more products,and long-term sustainable fishery yields are one of them. 展开更多
关键词 marine ranch size spectrum model fishing mortality cod-end mesh size
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Generation of ultra-flat broad spectrum with stable single-pulse mode-locking in double-clad Yb-doped fiber laser 认领 引用
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作者 Minghui Sun Dongxin Gao +4 位作者 Yunli Yu Wenyu Wang Qingcao Liu Weixin Liu Yuzhai Pan 《Chinese Physics B》 SCIE EI CAS CSCD 2026年第1期474-480,共7页
We achieved an ultra-flat broad spectrum output with a 20-dB bandwidth of 77.85 nm in a double-clad Yb-doped fiber laser.The intensity difference between the highest and lowest points of the spectrum indicates a flatn... We achieved an ultra-flat broad spectrum output with a 20-dB bandwidth of 77.85 nm in a double-clad Yb-doped fiber laser.The intensity difference between the highest and lowest points of the spectrum indicates a flatness better than4 dB.More notably,this ultra-flat broad spectrum maintains a stable single-pulse mode-locking state.With the increase of pump power,an ultra-wide spectrum with a 20-dB bandwidth approaching 100 nm was formed at a pump power of 2.25 W.Additionally,we obtained a 9-pulse mode-locked state at another PC station with the same pump,which is the highest number of stable mode-locked pulse bursts observed so far with a first-order Raman frequency shift.This fiber laser shows its benefits of ultra-flat broad spectrum,high stability,and ease of fabrication,which provides a new method of obtaining the broadband light source for multiple practical applications. 展开更多
关键词 ultra-flat broad spectrum high stability double-clad Yb-doped fiber mode-locked multi-pulse bursts
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Severe load spectrum development for transport aircraft from measured load data:A representative flight method 认领 引用
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作者 Kunyu WEI Xiaofan HE 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第5期347-363,共17页
The development of severe load spectrum is essential for evaluating the durability and damage tolerance of transport aircraft structure to ensure safety and economic viability.However,traditional methods have lacked c... The development of severe load spectrum is essential for evaluating the durability and damage tolerance of transport aircraft structure to ensure safety and economic viability.However,traditional methods have lacked consensus on severity selection and often distort load sequences,which undermines reliability in full-scale fatigue testing.This study introduces a novel framework for developing high-fidelity severe Flight-by-Flight(F-B-F)spectrum from measured fleet load data.Statistical modelling of load variations within a specific transport aircraft fleet is used to establish severe damage criteria.Subsequently,flight data meeting these criteria are extracted to develop a severe load spectrum that accurately reproduces the actual severe load sequences.The accuracy and reliability of the spectrum developed are validated through fatigue tests on 2024-T3 aluminum alloy specimens with a centered hole.This approach bridges the gap between severe damage quantification and spectrum development,providing a robust method for generating reliable severe F-B-F spectrum. 展开更多
关键词 Fatigue damage Fatigue load Fatigue testing Representative flight Spectrum analysis Severe load spectrum
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