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Intermittent melena and refractory anemia due to jejunal cavernous lymphangioma:A case report

World Journal of Gastrointestinal Surgery 2024年第4期16卷 1208-1214页

作者： Kai-Rui Liu Sheng Zhang wei-run chen You-Xing Huang Xu-Guang Li Department of Abdominal Surgery The Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510000Guangdong ProvinceChina Department of General Surgery The Affiliated Brain Hospital of Guangzhou Medical UniversityGuangzhou 510000Guangdong ProvinceChina Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and The Ministry of Education of China Guangzhou Medical UniversityGuangzhou 510000Guangdong ProvinceChina

BACKGROUND Lymphangiomas in the gastrointestinal tract are extremely rare in *** a benign lesion,small intestine lymphangiomas often remain asymptomatic and pose challenges for definitive ***,lymphangiomas can give rise to complications such as abdominal pain,bleeding,volvulus,and ***,we report a case of jejunal cavernous lymphangioma that presented with intermittent melena and refractory anemia in a male *** SUMMARY A 66-year-old man presented with intermittent melena,fatigue and refractory anemia nine months *** and colonoscopy were performed many times and revealed no apparent *** management,including transfusion,hemostasis,gastric acid secretion inhibition and symptomatic treatment,was performed,but the lesions tended to recur shortly after ***,the patient underwent capsule endoscopy,which revealed a more than 10 cm lesion accompanied by active *** singleballoon enteroscopy and biopsy,a diagnosis of jejunal cavernous lymphangioma was confirmed,and the patient underwent surgical *** complications or recurrences were observed *** Jejunal cavernous lymphangioma should be considered a cause of obscure gastrointestinal *** endoscopy and single-balloon enteroscopy can facilitate *** resection is an effective management method.

关键词： Intermittent melena Refractory anemia Capsule endoscopy Single-balloon enteroscopy Jejunal cavernous lymphangioma Enterectomy Case report

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Enhancement of comprehensive properties of Nb–Si based in-situ composites by Ho rare earth doping

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Rare Metals 2024年第9期43卷 4508-4520页

作者： wei wei Qi Wang Rui-run chen Chao-Wen Zheng Yan-Qing Su National Key Laboratory for Precision Hot Processing of Metals School of Materials Science and EngineeringHarbin Institute of Technology

This study examines the microstructure,mechanical properties （with a focus on room-temperature toughness）, and oxidation resistance of Ho-doped NbDSi based in-situ composites. The base alloy consists of the coarse primary Nb5Si3phase and the Nb5Si3+Nbss （Nb solid solution） eutectic cells. Ho doping influences the solidification path. When the Ho doping is higher than0.2 at%, the alloys transform into eutectic alloys. Ho can be solid-solved in trace amounts in the Nbss phase. However, most of Ho forms a stable Ho oxide phase, which alleviates oxygen contamination problem to some ***, the interface separation between Ho oxide and other phases reduces the plastic deformation ***, with 0.4 at%Ho doping, the KQvalue is18.03 MPa·m1/2, which is 31.1%higher than that of the base alloy. The strength of the Ho-doped alloys does not deteriorate with an increase in toughness. However, the large network-like Ho2O3in the 0.8Ho alloy causes a decrease in toughness and strength. In addition, the Ho oxide phase effectively blocks the inward oxygen *** 0.8 at%Ho doping, the oxidation mass gain per unit area is 10.16 mg·cm2, which is 39.7%lower than that of the base alloy.

关键词： Ho Microstructure Nb–Si based composites Properties Rare earth elements

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Ceramic-based meta-material absorber with high-temperature stability

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Rare Metals 2024年第9期43卷 4433-4440页

作者： Xing-Cong chen wei-Jia Luo run-Ni Zhao Yong-Zheng Wen Ji Zhou State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua University

With the continuous exploration of uncharted and extreme environments,enhanced temperature robustness of passive devices has become particularly *** this study,a ceramic-based meta-material absorber with exceptional temperature stability is developed using a fusion design approach that combines rare metal-based tungsten bronze structural ceramics and ***,the absorbance of the meta-material array based on Mie resonance exceeds 49.0%in both waveguides and free space,approaching the theoretical *** to impedance analysis,the absorption performance can be distinctly correlated with the dielectric loss （Q_f）.Notably,the high-temperature robustness is verified to still be effective at 400℃.These advancements in our design allow for the use of monolithic materials in fabricating temperature-stable perfect absorbers,providing greater freedom in the dielectric performance and expanding their potential applications,including in space exploration and 5G millimeter-wave scenarios.

关键词： Meta-material absorber Microwave absorption Miniaturization Rare metal-based ceramics Temperature robustness

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Laser powder bed fusion of NiTiFe shape memory alloy via premixed powder:microstructural evolution,mechanical and functional properties

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Rare Metals 2024年第5期43卷 2300-2316页

作者： Bo Yuan Jin-Guo Ge Liang Zhang Hong-Jun chen Long-Sha wei Yu-Duo Zhou run-Hua Song Institute of Intelligent Manufacturing Technology Shenzhen PolytechnicShenzhen 518055China School of Mechanical and Electrical Engineering Guilin University of Electronic TechnologyGuilin 541004China Guangdong Advanced Polymer Composite Engineering Technology Research Center Shenzhen Academy of Aerospace TechnologyShenzhen 518057China Jihua Laboratory Testing Center Jihua LaboratoryFoshan 528000China

High-cost pre-alloyed powder is the bottleneck problem that limits the widespread application of additivemanufactured shape memory *** this work,the lowcost ternary NiTiFe shape memory alloy is fabricated by laser powder bed fusion(LPBF)technique via mechanically mixed pre-alloy NiTi powder and varying contents pure Fe powder(1,2,3 wt%).All NiTiFe alloys show a relative density of up to 99.8%by optimizing the LPBF processing *** to the heterogeneous nucleation effect of micron-sized Fe particles,both grain refinement and texture weakening are generated in the NiTiFe alloys,accompanied by the reduction of dislocation *** the room-temperature mechanical properties,the NiTi-3Fe alloy shows the highest microhardness of HV370,but the fracture strength and elongation reduce to1701 MPa and 23%*** evolution of mechanical properties is attributed to the high internal defects,low dislocation density and the incoherent ***,the NiTi-3Fe alloy shows the quasi-linear superelasticity behavior;the superelastic recoverable strain of NiTi-1Fe and NiTi-2Fe decreased with the increase in Fe *** study provided a new-fangled insight for the development of multi-component NiTi-based shape memory alloys by additive manufacturing.

关键词： Additive manufacturing Shape memory alloy Metal matrix composite Microstructure Mechanical properties

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Deep learning-based optical aberration estimation enables offline digital adaptive optics and super-resolution imaging

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Photonics Research 2024年第3期12卷 474-484页

作者： CHANG QIAO HAOYU chen run WANG TAO JIANG YUWANG WANG DONG LI Department of Automation Tsinghua UniversityBeijing 100084China Institute for Brain and Cognitive Sciences Tsinghua UniversityBeijing 100084China National Laboratory of Biomacromolecules New Cornerstone Science LaboratoryCAS Center for Excellence in BiomacromoleculesInstitute of BiophysicsChinese Academy of SciencesBeijing 100101China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China

Optical aberrations degrade the performance of fluorescence *** adaptive optics(AO)leverages specific devices,such as the Shack–Hartmann wavefront sensor and deformable mirror,to measure and correct optical ***,conventional AO requires either additional hardware or a more complicated imaging procedure,resulting in higher cost or a lower acquisition *** this study,we proposed a novel space-frequency encoding network(SFE-Net)that can directly estimate the aberrated point spread functions(PSFs)from biological images,enabling fast optical aberration estimation with high accuracy without engaging extra optics and image *** showed that with the estimated PSFs,the optical aberration can be computationally removed by the deconvolution ***,to fully exploit the benefits of SFE-Net,we incorporated the estimated PSF with neural network architecture design to devise an aberration-aware deeplearning super-resolution model,dubbed *** demonstrated that the combination of SFE-Net and SFT-DFCAN enables instant digital AO and optical aberration-aware super-resolution reconstruction for live-cell imaging.

关键词： optics resolution enable

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Defect-mode and Fabry-Perot resonance induced multi-band nonreciprocal thermal radiation

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Science China Technological Sciences 2024年第8期67卷 2405-2412页

作者： chen ZiHe YU ShiLv YUAN cheng CUI XinYou HU run School of Energy and Power Engineering Huazhong University of Science and Technology Wuhan Fiberhome Fuhua Electric Co. Ltd.

According to Kirchhoff's radiation law, the spectral-directional absorptivity(α) and spectral-directional emissivity(e) of an object are widely believed to be identical, which places a fundamental limit on photonic energy conversion and *** introduction of Weyl semimetals and magneto-optical(MO) materials into photonic crystals makes it possible to violate Kirchhoff's law, but most existing work only report the unequal absorptivity and emissivity spectra in a single band, which cannot meet the requirements of most practical applications. Here, we introduce a defect layer into the structure composed of one-dimensional(1D) magnetophotonic crystal and a metal layer, which realizes dual-band nonreciprocal thermal radiation under a 3-T magnetic field with an incident angle of 60°. The realization of dual-band nonreciprocal radiation is mainly due to the Fabry-Perot(FP) resonance occurring in the defect layer and the excitation of Tamm plasmon, which is proved by calculating the magnetic field distribution. In addition, the effects of incident angle and structural parameters on nonreciprocity are also *** is more, the number of nonreciprocal bands could be further increased by tuning the defect layer thickness. When the defect layer thickness increases to 18.2 μm, tri-band nonreciprocal thermal radiation is realized due to the enhanced number of defect modes in the photonic band gap and the FP resonance occurring in the defect layer. Finally, the effect of defect location on nonreciprocity is also discussed. The present work provides a new way for the design of multi-band or even broad-band nonreciprocal thermal emitters.

关键词： Kirchhoff’s law multi-band nonreciprocal thermal radiation magnetophotonic crystal Tamm plasmon defect layer Fabry-Perot resonance

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Aerial target threat assessment based on gated recurrent unit and self-attention mechanism

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Journal of Systems Engineering and Electronics 2024年第2期35卷 361-373页

作者： chen chen QUAN wei SHAO Zhuang School of Automation Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing 100081China

Aerial threat assessment is a crucial link in modern air combat, whose result counts a great deal for commanders to make decisions. With the consideration that the existing threat assessment methods have difficulties in dealing with high dimensional time series target data, a threat assessment method based on self-attention mechanism and gated recurrent unit(SAGRU) is proposed. Firstly, a threat feature system including air combat situations and capability features is established. Moreover, a data augmentation process based on fractional Fourier transform(FRFT) is applied to extract more valuable information from time series situation features. Furthermore, aiming to capture key characteristics of battlefield evolution, a bidirectional GRU and SA mechanisms are designed for enhanced ***, after the concatenation of the processed air combat situation and capability features, the target threat level will be predicted by fully connected neural layers and the softmax classifier. Finally, in order to validate this model, an air combat dataset generated by a combat simulation system is introduced for model training and testing. The comparison experiments show the proposed model has structural rationality and can perform threat assessment faster and more accurately than the other existing models based on deep learning.

关键词： target threat assessment gated recurrent unit(GRU) self-attention(SA) fractional Fourier transform(FRFT)

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Improved Flexible Triboelectric Nanogenerator Based on Tile-Nanostructure for Wireless Human Health Monitor

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Energy & Environmental Materials 2024年第4期7卷 386-395页

作者： Huamin chen Shujun Guo Shaochun Zhang Yu Xiao wei Yang Zhaoyang Sun Xu Cai run Fang Huining Wang Yun Xu Jun Wang Zhou Li Fujian Key Laboratory of Functional Marine Sensing Materials Minjiang University Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences Institute of Semiconductors Chinese Academy of Sciences Beijing Key Laboratory of Inorganic Stretchable and Flexible Information Technology Faculty of Science and Engineering The University of Nottingham Ningbo China

Triboelectric nanogenerators (TENCs) have emerged as promising candidates for integrating with flexible electronics as self-powered systems owing to their intrinsic flexibility,biocompatibility,and *** this study,an improved flexible TENC with a tile-nanostructured MXene/polymethyl methacrylate (PMMA) composite electrode (MP-TENC) is proposed for use in wireless human health monitor.

关键词： flexible electrode MXene tile nanostructure triboelectric nanogenerator wireless monitor

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C-terminal frameshift mutations generate viable knockout mutants with developmental defects for three essential protein kinases

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aBIOTECH 2024年第2期5卷 219-224页

作者： Yun Zhang Miao-Miao Cui run-Nan Ke Yue-Dan chen Kabin Xie National Key Laboratory of Crop Genetic Improvement Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhan 430070China Hubei Key Laboratory of Plant Pathology Huazhong Agricultural UniversityWuhan 430070China

Loss-of-function mutants are fundamental resources for gene function ***,it is difficult to generate viable and heritable knockout mutants for essential ***,we show that targeted editing of the C-terminal sequence of the embryo lethal gene MITOGEN-ACTIVATED PROTEIN KINASES 1(OsMPK1)results in weak *** C-terminal-edited osmpk1 mutants displayed severe developmental defects and altered disease resistance but generated tens of viable seeds that inherited the *** the same C-terminal editing approach,we also obtained viable mutants for a wallassociated protein kinase(Os07g0493200)and a leucine-rich repeat receptor-like protein kinase(Os01g0239700),while the null mutations of these genes were *** data suggest that protein kinase activity could be reduced by introducing frameshift mutations adjacent to the C-terminus,which could generate valuable resources for gene function studies and tune protein kinase activity for signaling pathway engineering.

关键词： CRISPR/Cas9 Lethal mutant Protein kinases Genome editing C-terminus

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Is the Cape Stone Forest in Shantou City formed by wave erosion? A comparison of the pedestal rocks on the coasts and the mountains of Queshi in eastern Guangdong, China

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Journal of Mountain Science 2024年第5期21卷 1447-1463页

作者： chen Min WANG wei School of Geography South China Normal UniversityGuangzhou 510631China

Cape Stone Forest is a group of granite rock pillars(pedestal rocks) towering over Shilin Lake, on the southern shore of Shantou Bay in eastern Guangdong, China. The rock pillars were previously identified as sea stacks because they have marine notch-like concave sidewalls at their base, and more importantly, the lake is immediately adjacent to the bay, which is exposed to the open sea. However, rock pillars similar in shape and size can also be found at the top of Queshi Mountain, which is only about 300 meters northwest of the lake and about 85 meters above sea level. Therefore, the marine origin of Cape Stone Forest is seriously questioned. In this study, 3D imagery and drone technology were used to collect data in the investigations without direct manual measurements in the water or on the mountain. It shows that the concave sidewalls of the rock pillars in the lake and on the mountains occur at different heights and are exposed to different directions, while a natural sea stack on Mayu Island at the mouth of Shantou Bay has a horizontal notch parallel to the sea level, although the granite rock of the sea stack is the same as that of the lake and the mountains. The eastern side of the island, where the sea stack is located, is exposed to the open sea but blocks large waves for the rock pillars in the lake. Therefore, the origin of Cape Stone Forest cannot be explained by wave-based mechanisms. The only satisfactory explanation that takes into account all the field evidence is that the narrow rock pillars of the lake and mountain were formed by chemical weathering that penetrated closely the spaced joints of the granite rock, and the notch-like concave sidewalls were formed by more effective chemical weathering at the base of the pillars.

关键词： Pedestal rock Granite Closely spaced joints Wave erosion Chemical weathering

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