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Journal of Systems Engineering and Electronics 2024年第1期35卷 24-30页

作者： tian Jing ZHANG Wei School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Electromagnetic Space Security Chengdu 610036China

In engineering application,there is only one adaptive weights estimated by most of traditional early warning radars for adaptive interference suppression in a pulse reputation interval(PRI).Therefore,if the training samples used to calculate the weight vector does not contain the jamming,then the jamming cannot be removed by adaptive spatial filtering.If the weight vector is constantly updated in the range dimension,the training data may contain target echo signals,resulting in signal cancellation effect.To cope with the situation that the training samples are contaminated by target signal,an iterative training sample selection method based on non-homogeneous detector(NHD)is proposed in this paper for updating the weight vector in entire range dimension.The principle is presented,and the validity is proven by simulation results.

关键词： adaptive radar beamforming training sample selection non-homogeneous detector electronic jamming jamming suppression

Transformer and GAN-Based Super-Resolution Reconstruction Network for Medical Images

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Tsinghua Science and Technology 2024年第1期29卷 197-206页

作者： Weizhi Du Shihao tian Arts&Sciences College Washington University in St.LouisSt.LouisMO 63130USA Department of Electric and Computing Engineering Cornell UniversityIthacaNY 14850USA

Super-resolution reconstruction in medical imaging has become more demanding due to the necessity of obtaining high-quality images with minimal radiation dose,such as in low-field magnetic resonance imaging(MRI).However,image super-resolution reconstruction remains a difficult task because of the complexity and high textual requirements for diagnosis purpose.In this paper,we offer a deep learning based strategy for reconstructing medical images from low resolutions utilizing Transformer and generative adversarial networks(T-GANs).The integrated system can extract more precise texture information and focus more on important locations through global image matching after successfully inserting Transformer into the generative adversarial network for picture reconstruction.Furthermore,we weighted the combination of content loss,adversarial loss,and adversarial feature loss as the final multi-task loss function during the training of our proposed model T-GAN.In comparison to established measures like peak signal-to-noise ratio(PSNR)and structural similarity index measure(SSIM),our suggested T-GAN achieves optimal performance and recovers more texture features in super-resolution reconstruction of MRI scanned images of the knees and belly.

关键词： super-resolution image reconstruction Transformer generative adversarial network(GAN)

Two-grid Method of Expanded Mixed Finite Element Approximations for Parabolic Integro-differential Optimal Control Problems

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Acta Mathematicae Applicatae Sinica 2024年

作者： Yan-ping CHEN Jian-wei zhou tian-liang HOU School of Science Nanjing University of Posts and Telecommunications School of Mathematics and Statistics Linyi University School of Mathematics and Statistics Beihua University

This paper aims to construct a two-grid scheme of fully discretized expanded mixed finite element methods for optimal control problems governed by parabolic integro-differential equations and discuss a priori error estimates. The state variables and co-state variables are discretized by the lowest order Raviart-Thomas mixed finite element, and the control variable is approximated by piecewise constant functions. The time derivative is discretized by the backward Euler method. Firstly, we define some new mixed elliptic projections and prove the corresponding error estimates which play an important role in subsequent convergence analysis.Secondly, we derive a priori error estimates for all variables. Thirdly, we present a two-grid scheme and analyze its convergence. In the two-grid scheme, the solution of the parabolic optimal control problem on a fine grid is reduced to the solution of the parabolic optimal control problem on a much coarser grid and the solution of a decoupled linear algebraic system on the fine grid and the resulting solution still maintains an asymptotically optimal accuracy. At last, a numerical example is presented to verify the theoretical results.

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Polarization-dependent photoinduced metal–insulator transitions in manganites

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Science Bulletin 2024年第2期69卷 183-189页

作者： Lina Deng Weiye Zhang Hanxuan Lin Lifen Xiang Ying Xu Yadi Wang Qiang Li Yinyan Zhu Xiaodong zhou Wenbin Wang Lifeng Yin Hangwen Guo Chuanshan tian Jian Shen State Key Laboratory of Surface Physics Institute for Nanoelectronic Devices and Quantum Computingand Department of PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Quantum Sciences Shanghai 201315China Zhangjiang Fudan International Innovation Center Fudan UniversityShanghai 201210China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China Shanghai Branch CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum PhysicsShanghai 201315China

In correlated oxides,collaborative manipulation on light intensity,wavelength,pulse duration and polarization has yielded many exotic discoveries,such as phase transitions and novel quantum states.In view of potential optoelectronic applications,tailoring long-lived static properties by light-induced effects is highly desirable.So far,the polarization state of light has rarely been reported as a control parameter for this purpose.Here,we report polarization-dependent metal-to-insulator transition(MIT)in phaseseparated manganite thin films,introducing a new degree of freedom to control static MIT.Specifically,we observed giant photoinduced resistance jumps with striking features:(1)a single resistance jump occurs upon a linearly polarized light incident with a chosen polarization angle,and a second resistance jump occurs when the polarization angle changes;(2)the amplitude of the second resistance jump depends sensitively on the actual change of the polarization angles.Linear transmittance measurements reveal that the origin of the above phenomena is closely related to the coexistence of anisotropic micro-domains.Our results represent a first step to utilize light polarization as an active knob to manipulate static phase transitions,pointing towards new pathways for nonvolatile optoelectronic devices and sensors.

关键词： Metal-insulator phase transitions Polarization of light Electronic phase separation Selective domain controllability

Mannitol inhibits the proliferation of neural stem cell by a p38 mitogen-activated protein kinase-dependent signaling pathway

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Chinese Journal of Traumatology 2024年第1期27卷 42-52页

作者： Hai-Zhen Duan Xin zhou Quan Hu Meng-Long Liu Shu-Hong Wang Ji Zhang Xu-Heng Jiang tian-Xi Zhang An-Yong Yu Department of Emergency Affiliated Hospital of Zunyi Medical UniversityZunyi563000Guizhou provinceChina Dazhou Vocational College of Chinese Medicine Dazhou635000Sichuan provinceChina Dachuan District Traditional Chinese Medicine Hospital Dazhou635000Sichuan provinceChina

Purpose:Mannitol is one of the first-line drugs for reducing cerebral edema through increasing the extracellular osmotic pressure.However,long-term administration of mannitol in the treatment of cerebral edema triggers damage to neurons and astrocytes.Given that neural stem cell(NSC)is a subpopulation of main regenerative cells in the central nervous system after injury,the effect of mannitol on NSC is still elusive.The present study aims to elucidate the role of mannitol in NSC proliferation.Methods:C57 mice were derived from the animal house of Zunyi Medical University.A total of 15 pregnant mice were employed for the purpose of isolating NSCs in this investigation.Initially,mouse primary NSCs were isolated from the embryonic cortex of mice and subsequently identified through immunofluorescence staining.In order to investigate the impact of mannitol on NSC proliferation,both cell counting kit-8 assays and neurospheres formation assays were conducted.Thein vitro effects of mannitol were examined at various doses and time points.In order to elucidate the role of Aquaporin 4(AQP4)in the suppressive effect of mannitol on NSC proliferation,various assays including reverse transcription polymerase chain reaction,western blotting,and immunocytochemistry were conducted on control and mannitol-treated groups.Additionally,the phosphorylated p38(p-p38)was examined to explore the potential mechanism underlying the inhibitory effect of mannitol on NSC proliferation.Finally,to further confirm the involvement of the p38 mitogen-activated protein kinase-dependent(MAPK)signaling pathway in the observed inhibition of NSC proliferation by mannitol,SB203580 was employed.All data were analyzed using SPSS 20.0 software(SPSS,Inc.,Chicago,IL).The statistical analysis among multiple comparisons was performed using one-way analysis of variance(ANOVA),followed by Turkey’’s post hoc test in case of the data following a normal distribution using a Shapiro-Wilk normality test.Comparisons between 2 groups were determined using Student’s t-te

关键词： Mannitol Cerebral edema Neural stem cell Proliferation AQP4 p38 MAPK signaling pathway

Dynamic simulation insights into friction weakening effect on rapid long-runout landslides:A case study of the Yigong landslide in the Tibetan Plateau,China

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China Geology 2024年第2期7卷 222-236页

作者： Zi-zheng Guo Xin-yong zhou Da Huang Shi-jie Zhai Bi-xia tian Guang-ming Li School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China School of Geological Engineering and Geomatics Chang’an UniversityXi’an 710054China tianjin Municipal Engineering Design&Research Institute(TMEDI) Tianjin 300392China

This study proposed a novel friction law dependent on velocity,displacement and normal stress for kinematic analysis of runout process of rapid landslides.The well-known Yigong landslide occurring in the Tibetan Plateau of China was employed as the case,and the derived dynamic friction formula was included into the numerical simulation based on Particle Flow Code.Results showed that the friction decreased quickly from 0.64(the peak)to 0.1(the stead value)during the 5s-period after the sliding initiation,which explained the behavior of rapid movement of the landslide.The monitored balls set at different sections of the mass showed similar variation characteritics regarding the velocity,namely evident increase at the initial phase of the movement,followed by a fluctuation phase and then a stopping one.The peak velocity was more than 100 m/s and most particles had low velocities at 300s after the landslide initiation.The spreading distance of the landslide was calculated at the two-dimension(profile)and three-dimension scale,respectively.Compared with the simulation result without considering friction weakening effect,our results indicated a max distance of about 10 km from the initial unstable position,which fit better with the actual situation.

关键词： Rapid long-runout landslide PFC Friction weakening Three-dimension Numerical simulation Tibetan Plateau Hydrogeology Engineering Geological hazards survey engineering

Revisiting East Asian monsoon change during the Last Glacial Maximum using PMIP4 simulations

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Atmospheric and Oceanic Science Letters 2024年第3期17卷 47-52页

作者： Zhiping tian Institute of Atmospheric Physics Chinese Academy of SciencesBeijingChina

利用PMIP4多模式试验数据,本文重新检查了末次冰盛期(距今约21000年)东亚季风变化.结果表明:相对于工业革命前期,所有5个模式一致模拟显示末次冰盛期东亚季风减弱,冬季和夏季减幅分别为1%-18%和2-32%;不同模式中东亚季风环流变化的空间... 详细信息

利用PMIP4多模式试验数据,本文重新检查了末次冰盛期(距今约21000年)东亚季风变化.结果表明:相对于工业革命前期,所有5个模式一致模拟显示末次冰盛期东亚季风减弱,冬季和夏季减幅分别为1%-18%和2-32%;不同模式中东亚季风环流变化的空间分布存在差异,这主要源于该时期大尺度变冷和海平面气压梯度变化的空间分布不同;由于模式之间的差异和重建记录之间的不确定性,未来有待开展更多模拟和重建工作以更好地理解冰期东亚季风变化.

关键词：末次冰盛期东亚冬季风东亚夏季风 PMIP4试验

Efficacy comparison of fruquintinib,regorafenib monotherapy or plus programmed death-1 inhibitors for microsatellite stable metastatic colorectal cancer

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2449-2462页

作者： tian-Qi An Hui Qiu Quan-Bo zhou Hong Zong Shuang Hu Yu-Gui Lian Rui-Hua Zhao Department of Oncology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450000Henan ProvinceChina Department of Hepato-Pancreato-Biliary Surgery Peking University Cancer Hospital and InstituteBeijing 100000China Department of Colorectal Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450000Henan ProvinceChina

BACKGROUND Regorafenib(R)and fruquintinib(F)are the standard third-line regimens for colorectal cancer(CRC)according to the National Comprehensive Cancer Network guidelines,but both have limited efficacy.Several phase 2 trials have indicated that R or F combined with immune checkpoint inhibitors can reverse immunosuppression and achieve promising efficacy for microsatellite stable or proficient mismatch repair(MSS/pMMR)CRC.Due to the lack of studies comparing the efficacy between F,R,F plus programmed death-1(PD-1)inhibitor,and R plus PD-1 inhibitors(RP),it is still unclear whether the combination therapy is more effective than monotherapy.AIM To provide critical evidence for selecting the appropriate drugs for MSS/pMMR metastatic CRC(mCRC)patients in clinical practice.METHODS A total of 2639 CRC patients were enrolled from January 2018 to September 2022 in our hospital,and 313 MSS/pMMR mCRC patients were finally included.RESULTS A total of 313 eligible patients were divided into F(n=70),R(n=67),F plus PD-1 inhibitor(FP)(n=95)and RP(n=81)groups.The key clinical characteristics were well balanced among the groups.The median progression-free survival(PFS)of the F,R,FP,and RP groups was 3.5 months,3.6 months,4.9 months,and 3.0 months,respectively.The median overall survival(OS)was 14.6 months,15.7 months,16.7 months,and 14.1 months.The FP regimen had an improved disease control rate(DCR)(P=0.044)and 6-month PFS(P=0.014)and exhibited a better trend in PFS(P=0.057)compared with F,and it was also significantly better in PFS than RP(P=0.030).RP did not confer a significant survival benefit;instead,the R group had a trend toward greater benefit with OS(P=0.080)compared with RP.No significant differences were observed between the R and F groups in PFS or OS(P>0.05).CONCLUSION FP is superior to F in achieving 6-month PFS and DCR,while RP is not better than R.FP has an improved PFS and 6-month PFS compared with RP,but F and R had similar clinical efficacy.Therefore,FP may be a highly promising strategy in the treatment of M

关键词： Colorectal cancer Fruquintinib Regorafenib Programmed death-1 inhibitor Real-world

Simultaneous quantification of trace heavy metals in mushrooms using a three-dimensional highly reduced graphene oxide/FeOnanocomposite-based electrochemical sensor

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Food Science and Human Wellness 2024年

作者： Yiming tian Pingsheng Zhong Kai zhou Lufei Zheng Jiali Ren Hunan Key Laboratory of Forestry Edible Resources Safety and Processing Hunan Key Laboratory of Grain-oil Deep Process and Quality Control Central South University of Forestry and Technology Institute of Quality Standard and Testing Technology for Agro-Products of CAAS

The accumulation of heavy metals in mushrooms has presented a significant risk to human health， underscoring the importance of devising a portable and cost-effective method for detecting heavy metals. Thus， we have developed an electrochemical sensor based on 3-dimensional highly reduced graphene oxide (3D-HRGO) in conjunction with Fe3O4nanoparticles， enabling the simultaneous quantification of Cd2+， Pb2+， Cu2+， and Hg2+. The 3D-HRGO/Fe3O4nano-particles material prepared in this study was characterized and confirmed by multiple techniques， then dispersed in a simple and environmental dispersant， consist of 75% ethanol and 0.1% Nafion， and coating on a glass carbon electrode (GCE) to preparing a 3D-HRGO/Fe3O4/GCE sensor. The limit of detection (LOD) of 3D-HRGO/Fe3O4/GCE sensor for Cd2+， Pb2+， Cu2+， and Hg2+in simultaneous detection were 0.2 μg/L， 0.6 μg/L， 0.6 μg/L， and 0.9 μg/L， respectively. The sensor demonstrates exceptional stability， reproducibility， anti-interference， and recovery rate. Furthermore， the electrochemical sensor was employed to detect heavy metals in actual mushrooms and validated through conventional methodologies. This study represents the pioneering utilization of 3D-HRGO/Fe3O4as a foundational material for an electrochemical sensor capable of simultaneous detection of multiple metals， thereby advancing the progress of on-site and expeditious detection techniques.

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Woven fabric triboelectric nanogenerators for human-computer interaction and physical health monitoring

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Nano Research 2024年第6期17卷 5540-5548页

作者： Yu Miao Mengjuan zhou Jia Yi Yanyan Wang Guangjin tian Hongxia Zhang Wenlong Huang Wenhao Wang Ronghui Wu Liyun Ma College of Textile and Clothing Xinjiang UniversityUrumqi 830046China College of Textiles Donghua UniversityShanghai 201620China College of Physics Xiamen UniversityXiamen 201620China Department of Bioengineering Imperial College LondonLondon SW72AZUK

Triboelectric nanogenerator(TENG)converts mechanical energy into valuable electrical energy,offering a solution for future energy needs.As an indispensable part of TENG,textile TENG(T-TENG)has incredible advantages in harvesting biomechanical energy and physiological signal monitoring.However,the application of T-TENG is restricted,partly because the fabric structure parameter and structure on T-TENG performance have not been fully exploited.This study comprehensively investigates the effect of weaving structure on fabric TENGs(F-TENGs)for direct-weaving yarn TENGs and post-coating fabric TENGs.For direct-weaving F-TENGs,a single-yarn TENG(Y-TENG)with a core-sheath structure is fabricated using conductive yarn as the core layer yarn and polytetrafluoroethylene(PTFE)filaments as the sheath yarn.Twelve fabrics with five different sets of parameters were designed and investigated.For post-coating F-TENGs,fabrics with weaving structures of plain,twill,satin,and reinforced twill were fabricated and coated with conductive silver paint.Overall,the twill F-TENGs have the best electrical outputs,followed by the satin F-TENGs and plain weave F-TENGs.Besides,the increase of the Y-TENG gap spacing was demonstrated to improve the electrical output performance.Moreover,T-TENGs are demonstrated for human-computer interaction and self-powered real-time monitoring.This systematic work provides guidance for the future T-TENG’s design.

关键词： single-yarn triboelectric nanogenerators woven fabric triboelectric nanogenerators fabric weaving structures and parameters human-computer interaction physical health monitoring