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A semantic segmentation-based underwater acoustic image transmission framework for cooperative SLAM

Defence technology（防务技术） 2024年第3期33卷 339-351页

作者： Jiaxu Li Guangyao Han Shuai Chang Xiaomei Fu school of Marine Science and technology Tianjin UniversityTianjin 300072China

With the development of underwater sonar detection technology,simultaneous localization and mapping(SLAM)approach has attracted much attention in underwater navigation field in recent *** the weak detection ability of a single vehicle limits the SLAM performance in wide ***,cooperative SLAM using multiple vehicles has become an important research *** key factor of cooperative SLAM is timely and efficient sonar image transmission among underwater ***,the limited bandwidth of underwater acoustic channels contradicts a large amount of sonar image *** is essential to compress the images before ***,deep neural networks have great value in image compression by virtue of the powerful learning ability of neural networks,but the existing sonar image compression methods based on neural network usually focus on the pixel-level information without the semantic-level *** this paper,we propose a novel underwater acoustic transmission scheme called UAT-SSIC that includes semantic segmentation-based sonar image compression(SSIC)framework and the joint source-channel codec,to improve the accuracy of the semantic information of the reconstructed sonar image at the *** SSIC framework consists of Auto-Encoder structure-based sonar image compression network,which is measured by a semantic segmentation network's *** that sonar images have the characteristics of blurred target edges,the semantic segmentation network used a special dilated convolution neural network(DiCNN)to enhance segmentation accuracy by expanding the range of receptive *** joint source-channel codec with unequal error protection is proposed that adjusts the power level of the transmitted data,which deal with sonar image transmission error caused by the serious underwater acoustic *** results demonstrate that our method preserves more semantic information,with advantages over existing methods at the sa

关键词： Semantic segmentation Sonar image transmission Learning-based compression

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Coexisting fast–slow dendritic traveling waves in a 3D-array electric field coupled neuronal network

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Chinese Physics B 2024年第6期33卷 614-626页

作者：魏熙乐任泽宇卢梅丽樊亚琴常思远 The tianjin Key Laboratory of Process Measurement and Control School of Electrical and Information EngineeringTianjin UniversityTianjin 300072China school of Information technology Engineering Tianjin University of Technology and EducationTianjin 300074China

Coexistence of fast and slow traveling waves without synaptic transmission has been found in hhhippocampal tissues,which is closely related to both normal brain activity and abnormal neural activity such as epileptic discharge. However, the propagation mechanism behind this coexistence phenomenon remains unclear. In this paper, a three-dimensional electric field coupled hippocampal neural network is established to investigate generation of coexisting spontaneous fast and slow traveling waves. This model captures two types of dendritic traveling waves propagating in both transverse and longitude directions: the N-methyl-D-aspartate(NMDA)-dependent wave with a speed of about 0.1 m/s and the Ca-dependent wave with a speed of about 0.009 m/s. These traveling waves are synaptic-independent and could be conducted only by the electric fields generated by neighboring neurons, which are basically consistent with the in vitro data measured experiments. It is also found that the slow Ca wave could trigger generation of fast NMDA waves in the propagation path of slow waves whereas fast NMDA waves cannot affect the propagation of slow Ca waves. These results suggest that dendritic Ca waves could acted as the source of the coexistence fast and slow waves. Furthermore, we also confirm the impact of cellular spacing heterogeneity on the onset of coexisting fast and slow waves. The local region with decreasing distances among neighbor neurons is more liable to promote the onset of spontaneous slow waves which, as sources, excite propagation of fast waves. These modeling studies provide possible biophysical mechanisms underlying the neural dynamics of spontaneous traveling waves in brain tissues.

关键词： hippocampal network epileptiform dendritic oscillation traveling wave electric field coupling

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Effect of applied electric fields on supralinear dendritic integration of interneuron

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Chinese Physics B 2024年第2期33卷 84-95页

作者：樊亚琴魏熙乐卢梅丽伊国胜 tianjin Key Laboratory of Process Measurement and Control School of Electrical and Information EngineeringTianjin UniversityTianjin 300072China school of Information technology Engineering Tianjin University of Technology and EducationTianjin 300222China

Evidences show that electric fields(EFs)induced by the magnetic stimulation could modulates brain activities by regulating the excitability of GABAergic ***,it is still unclear how and why the EF-induced polarization affects the interneuron response as the interneuron receives NMDA synaptic *** the key role of NMDA receptor-mediated supralinear dendritic integration in neuronal computations,we suppose that the applied EFs could functionally modulate interneurons’response via regulating dendritic *** first,we build a simplified multi-dendritic circuit model with inhomogeneous extracellular potentials,which characterizes the relationship among EF-induced spatial polarizations,dendritic integration,and somatic *** performing model-based singular perturbation analysis,it is found that the equilibrium point of fast subsystem can be used to asymptotically depict the subthreshold input–output(sI/O)relationship of dendritic *** predicted that EF-induced strong depolarizations on the distal dendrites reduce the dendritic saturation output by reducing driving force of synaptic input,and it shifts the steep change of sI/O curve left by reducing stimulation threshold of triggering NMDA ***,the EF modulation prefers the global dendritic integration with asymmetric scatter distribution of NMDA ***,we identify the respective contribution of EF-regulated dendritic integration and EF-induced somatic polarization to an action potential generation and find that they have an antagonistic effect on AP generation due to the varied NMDA spike threshold under EF stimulation.

关键词： GABAergic interneuron electrical field supralinear dendritic integration action potential generation

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Permeable and robust polymer-silica hybrid armor on cell catalyst for sustainable biomanufacturing

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Particuology 2024年第9期92卷 106-112页

作者： Yiran Cheng Zhenhua Wu Boyu Zhang Jiaxu Zhang Jiafu Shi Zhongyi Jiang school of Environmental Science and Engineering Tianjin UniversityTianjin300072China Key Laboratory for Green Chemical technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China

Inactivated cell catalysis is one of several central techniques in green biomanufacturing ***,the instability and leakage of enzymes in inactivated cell severely restrict the practical applications of inactivated cell *** armor on the surface of inactivated cells affords a feasible and effective strategy to enhance the stability of cells while commonly lowering the ***,polymer-silica hybrid armor(PSHA)is directly generated on the surface of enzyme-containing *** branched structure of PEI enables higher porosity of cell@PSHA,exhibiting 1.52-fold enhancement in substrate permeability by contrast with cell@silica armor(SA).The electrostatic interactions(NH_(3)^(+)with O^(−))and hydrogen bonding(N⋯H or O⋯H)interactions between structural units enables higher stability of cell@PSHA,showing 3.13-fold elevation in Young's modulus compared with cell@*** a result,the cell@PSHA can catalyze continuous conversion of starch to tagatose for 15 batches over 969 h,with an average yield of 77.76 g L^(−1).

关键词： Biomanufacturing Wholecell catalysis Polymer-silica hybrid armor Tagatose production Starch conversion

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Performance of physical-informed neural network (PINN) for the key parameter inference in Langmuir turbulence parameterization scheme

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Acta Oceanologica Sinica 2024年第5期43卷 121-132页

作者： Fangrui Xiu Zengan Deng school of Marine Science and technology Tianjin UniversityTianjin 300072China

The Stokes production coefficient(E_(6))constitutes a critical parameter within the Mellor-Yamada type(MY-type)Langmuir turbulence(LT)parameterization schemes,significantly affecting the simulation of turbulent kinetic energy,turbulent length scale,and vertical diffusivity coefficient for turbulent kinetic energy in the upper ***,the accurate determination of its value remains a pressing scientific *** study adopted an innovative approach by leveraging deep learning technology to address this challenge of inferring the E_(6).Through the integration of the information of the turbulent length scale equation into a physical-informed neural network(PINN),we achieved an accurate and physically meaningful inference of E_(6).Multiple cases were examined to assess the feasibility of PINN in this task,revealing that under optimal settings,the average mean squared error of the E_(6) inference was only 0.01,attesting to the effectiveness of *** optimal hyperparameter combination was identified using the Tanh activation function,along with a spatiotemporal sampling interval of 1 s and 0.1 *** resulted in a substantial reduction in the average bias of the E_(6) inference,ranging from O(10^(1))to O(10^(2))times compared with other *** study underscores the potential application of PINN in intricate marine environments,offering a novel and efficient method for optimizing MY-type LT parameterization schemes.

关键词： Langmuir turbulence physical-informed neural network parameter inference

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Design and engineering of logic genetic-enzymatic gates based on the activity of the human CYP2C9 enzyme in permeabilized Saccharomyces cerevisiae cells

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Synthetic and Systems Biotechnology 2024年第3期9卷 406-415页

作者： Rana Azeem Ashraf Matthias Bureik Mario Andrea Marchisio school of Pharmaceutical Science and technology Tianjin University300072TianjinChina

Gene circuits allow cells to carry out complex functions such as the precise regulation of biological metabolic *** this study,we combined,in the yeast ***,genetic regulatory elements with the enzymatic reactions of the human CYP2C9 and its redox partner CPR on luciferin substrates and *** cells were permeabilized and used as enzyme bags in order to host these metabolic *** engineered three different(genetic)-enzymatic basic Boolean gates(YES,NOT,and N-IMPLY).In the YES and N-IMPLY gates,human CYP2C9 was expressed under the galactose-inducible GAL1 *** carbon monoxide releasing molecule CORM-401 was used as an input in the NOT and N-IMPLY gates to impair CYP2C9 activity through inhibition of the Fe+2-heme prosthetic group in the active site of the human *** study provides a new approach in designing synthetic bio-circuits and optimizing experimental conditions to favor the heterologous expression of human drug metabolic enzymes over their endogenous *** new approach will help study precise metabolic attributes of human P450s.

关键词： Cytochrome P450 Drug metabolism Budding yeast Diclofenac Synthetic biology CORM-401 Boolean gates

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Optimal synthesis of heat-integrated distillation configurations using the two-column superstructure

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Chinese Journal of Chemical Engineering 2024年第2期66卷 238-249页

作者： Xiaodong Zhang Lu Jin Jinsheng Sun school of Chemical Engineering and technology Tianjin UniversityTianjin 300072China

In the realm of the synthesis of heat-integrated distillation configurations,the conventional approach for exploring more heat integration possibilities typically entails the splitting of a single column into a twocolumn ***,this approach frequently necessitates tedious enumeration procedures,resulting in a considerable computational *** surmount this formidable challenge,the present study introduces an innovative remedy:The proposition of a superstructure that encompasses both single-column and multiple two-column ***,a simultaneous optimization algorithm is applied to optimize both the process parameters and heat integration structures of the twocolumn *** effectiveness of this approach is demonstrated through a case study focusing on industrial organosilicon *** results underscore that the superstructure methodology not only substantially mitigates computational time compared to exhaustive enumeration but also furnishes solutions that exhibit comparable performance.

关键词： Superstructure Process synthesis Heat integration Simulation-based optimization Industrial organosilicon separation

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A multi-scale second-order autoregressive recursive filter approach for the sea ice concentration analysis

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Acta Oceanologica Sinica 2024年第3期43卷 115-126页

作者： Lu Yang Xuefeng Zhang school of Marine Science and technology Tianjin UniversityTianjin 300072China

To effectively extract multi-scale information from observation data and improve computational efficiency,a multi-scale second-order autoregressive recursive filter(MSRF)method is *** second-order autoregressive filter used in this study has been attempted to replace the traditional first-order recursive filter used in spatial multi-scale recursive filter(SMRF)*** experimental results indicate that the MSRF scheme successfully extracts various scale information resolved by ***,compared with the SMRF scheme,the MSRF scheme improves computational accuracy and efficiency to some *** MSRF scheme can not only propagate to a longer distance without the attenuation of innovation,but also reduce the mean absolute deviation between the reconstructed sea ice concentration results and observations reduced by about 3.2%compared to the SMRF *** the other hand,compared with traditional first-order recursive filters using in the SMRF scheme that multiple filters are executed,the MSRF scheme only needs to perform two filter processes in one iteration,greatly improving filtering *** the two-dimensional experiment of sea ice concentration,the calculation time of the MSRF scheme is only 1/7 of that of SMRF *** means that the MSRF scheme can achieve better performance with less computational cost,which is of great significance for further application in real-time ocean or sea ice data assimilation systems in the future.

关键词： second-order auto-regressive filter multi-scale recursive filter sea ice concentration three-dimensional variational data assimilation

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Nanoscale“precision strike”:Tumor microenvironment-responsive smart micelles for efficient targeted drug delivery

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Nano Research 2024年第9期17卷 8360-8367页

作者： Dong Wan Yarong Song Xiujuan Lu Yanfeng Huang Jianxin Zhang Yonghui Liu Yi Liu Jie Pan school of Chemistry Tiangong UniversityTianjin 300387China school of Chemical Engineering and technology Tiangong UniversityTianjin 300387China

To address the limitations of conventional nanotechnology-based drug delivery systems,this work developed enzyme and reduction dual-responsive polymeric *** micelles were synthesized with copolymers composed of TPGS_(3350)-PVGLIG-DOX(TPD)and FA-SS-DOX(FSD),which endow them with tumor-targeted drug delivery ***_(3350)contributes to extending the circulation of micelles in body,augmenting their accumulation in tumor tissues via the enhanced permeability and retention(EPR)*** localized the tumor site,matrix metalloproteinase 2(MMP2)cleaves the PVGLIG peptide moiety within the micelles,thereby releasing TPGS_(3350)and exposing the targeting ligand of *** approach enables the subsequent internalization of the micelles by tumor cells through folate receptor-mediated *** internalization,the high intracellular concentration of glutathione(GSH)triggers the reduction of the disulfide bond within the FA-SS-DOX,leading to the release of the anticancer-drug doxorubicin(DOX),which promotes apoptosis in the tumor cells and enhances the efficacy of chemotherapy.

关键词： cancer peptide micelle dual-responsive folate

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Effects of orientation on the fatigue crack growth behaviors of the ZK60 magnesium alloy in air and PBS

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Journal of Magnesium and Alloys 2024年第1期12卷 281-294页

作者： Jiaqi Hu Zheng Liu Zuoliang Ning Hong Gao school of Chemical Engineering and technology Tianjin UniversityTianjin 300072China tianjin Key Laboratory of Chemical Process Safety and Equipment technology Tianjin 300072China

Strong anisotropic corrosion and mechanical properties caused by specimen orientations greatly limit the applications of wrought magnesium *** investigate the influences of specimen orientation,the corrosion tests and(corrosion)fatigue crack growth tests were *** rolled and transverse surfaces of the materials show distinct corrosion rate differences in the stable corrosion stage,but the truth is the opposite for the initial stage of *** air,specimen orientations have a significant influence on the plastic deformation mechanisms near the crack tip,which results in different fatigue fracture surfaces and cracking *** with R-T specimens,N-T specimens show a slower fatigue crack growth(FCG)rate in air,which can be attributed to crack closure effects and deformation twinning near the crack *** corrosion environment will not significantly change the main plastic deformation mechanisms for the same type of ***,the FCG rate in phosphate buffer saline(PBS)is one order of magnitude higher than that in air,which is caused by the combined effects of hydrogen-induced cracking and anodic *** to the similar corrosion rates at crack tips,the specimens with different orientations display close FCG rates in PBS.

关键词： Magnesium alloy Orientation Corrosion Fatigue crack growth

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