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甜瓜HDM基因家族鉴定及特性分析
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作者 张治 张婧 +2 位作者 张瑾 哈斯阿古拉 郝金凤 《遗传》 CAS CSCD 北大核心 2024年第2期168-180,共13页
组蛋白去甲基化酶(histone demethylase,HDM)是生物生长过程中的重要调节因子之一,在植物的生长发育和环境适应过程中发挥着重要的调控作用。本研究通过生物信息学方法对甜瓜(Cucumis melo L.) HDM基因家族进行了鉴定,并通过转录组数据... 组蛋白去甲基化酶(histone demethylase,HDM)是生物生长过程中的重要调节因子之一,在植物的生长发育和环境适应过程中发挥着重要的调控作用。本研究通过生物信息学方法对甜瓜(Cucumis melo L.) HDM基因家族进行了鉴定,并通过转录组数据检测了其成员在甜瓜组织的表达特性。结果显示,在甜瓜基因组中鉴定得到了20个CmHDM基因,在各条染色体上非均匀分布;其成员可以分成LSD1和JmjC两大类,而JmjC类群又可划分为5个亚群,各类群成员数量不等;种内和种间的共线性关系显示,甜瓜HDM基因仅存在一对片段重复,与番茄(Solanum lycopersicum) HDM基因共线性区域较多,亲缘关系较近;各成员所含保守结构域数量不等,且外显子和内含子在数量上有所差异;在启动子区域存在多种与激素和环境信号响应的顺式作用元件,表达特性分析显示各基因成员在甜瓜雄花、雌花、根、茎、叶、子房和成熟果实中均存在不同程度的表达。这些结果将有助于更好地理解HDM基因的潜在功能以及它们在参与调节甜瓜生长发育和环境自适中可能发挥的作用。 展开更多
关键词 甜瓜 HDM家族 基因鉴定 表达分析
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Ultra-Robust and High-Performance Rotational Triboelectric Nanogenerator by Bearing Charge Pumping 被引量:2
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作者 Xianpeng Fu Yuhan Qin +6 位作者 zhi zhang Guoxu Liu Jie Cao Beibei Fan Zhaozheng Wang Zheng Wang Chi zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期343-349,共7页
As an emerging technology to convert environmental high-entropy energy into electrical energy,triboelectric nanogenerator(TENG)has great demands for further enhancing the service lifetime and output performance in pra... As an emerging technology to convert environmental high-entropy energy into electrical energy,triboelectric nanogenerator(TENG)has great demands for further enhancing the service lifetime and output performance in practical applications.Here,an ultra-robust and high-performance rotational triboelectric nanogenerator(R-TENG)by bearing charge pumping is proposed.The R-TENG composes of a pumping TENG(P-TENG),an output TENG(O-TENG),a voltage-multiplying circuit(VMC),and a buffer capacitor.The P-TENG is designed with freestanding mode based on a rolling ball bearing,which can also act as the rotating mechanical energy harvester.The output low charge from the P-TENG is accumulated and pumped to the non-contact O-TENG,which can simultaneously realize ultralow mechanical wear and high output performance.The matched instantaneous power of R-TENG is increased by 32 times under 300 r/min.Furthermore,the transferring charge of R-TENG can remain 95%during 15 days(6.4×10^(6)cycles)continuous operation.This work presents a realizable method to further enhance the durability of TENG,which would facilitate the practical applications of high-performance TENG in harvesting distributed ambient micro mechanical energy. 展开更多
关键词 bearing charge pumping triboelectric nanogenerators ultralow mechanical wear ultra-robust voltage-multiplying circuit
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Absent in melanoma 2 attenuates proliferation and migration and promotes apoptosis of human colorectal cancer cells by activating P38MAPK signaling pathway 被引量:1
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作者 zhi zhang XIAOSONG LI +7 位作者 YING zhang HAO ZHU ZHENGUO QIAO YANG LU XIUWEI MI HUIHUA CAO GENHAI SHEN SONGBING HE 《Oncology Research》 SCIE 2024年第2期353-360,共8页
Colorectal cancer(CRC)stands among the top prevalent cancers worldwide and holds a prominent position as a major contributor to cancer-related mortality globally.Absent in melanoma 2(AIM2),a constituent of the interfe... Colorectal cancer(CRC)stands among the top prevalent cancers worldwide and holds a prominent position as a major contributor to cancer-related mortality globally.Absent in melanoma 2(AIM2),a constituent of the interferoninducible hematopoietic interferon-inducible nuclear antigens with 200 amino acid repeats protein family,contributes to both cancer progression and inflammasome activation.Despite this understanding,the precise biological functions and molecular mechanisms governed by AIM2 in CRC remain elusive.Consequently,this study endeavors to assess AIM2’s expression levels,explore its potential antitumor effects,elucidate associated cancer-related processes,and decipher the underlying signaling pathways in CRC.Our findings showed a reduced AIM2 expression in most CRC cell lines.Elevation of AIM2 levels suppressed CRC cell proliferation and migration,altered cell cycle by inhibiting G1/S transition,and induced cell apoptosis.Further research uncovered the participation of P38 mitogen-activated protein kinase(P38MAPK)in AIM2-mediated modulation of CRC cell apoptosis and proliferation.Altogether,our achievements distinctly underscored AIM2’s antitumor role in CRC.AIM2 overexpression inhibited proliferation and migration and induced apoptosis of CRC cells via activating P38MAPK signaling pathway,indicating AIM2 as a prospective and novel therapeutic target for CRC. 展开更多
关键词 Absent in melanoma 2 PROLIFERATION MIGRATION Apoptosis P38MAPK Colorectal cancer
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Achieving thermodynamic stability of single-crystal ultrahigh-nickel cathodes via an alcohol-assisted mechanical fusion
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作者 zhi zhang Tiancheng Liu +9 位作者 Ce Gao Yun Liu Hailan Kuai Hongli Du Wanli You Xiaobing Huang Jixue Shen Haitao Huang Yuefeng Su Lai Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第12期580-592,共13页
Elevating the operating voltage is an effective approach to improve the reversible capacity of ultra-high nickel layered oxide cathode LiNi_(x)Co_(y)Mn_(z)O_(2)(NCM,x≥0.8)and solve the"range anxiety"confusi... Elevating the operating voltage is an effective approach to improve the reversible capacity of ultra-high nickel layered oxide cathode LiNi_(x)Co_(y)Mn_(z)O_(2)(NCM,x≥0.8)and solve the"range anxiety"confusion of electric vehicles.However,the undesirable surface reconstruction induced by the high cut-off voltage has a fatal impact on the thermodynamic stability of the material,inevitably leading to fast capacity degradation.Herein,a mechanical fusion aided by alcohol is suggested to create a stable olivine structure for the single-crystal(SC)ultrahigh-nickel cathode LiNi_(0.92)Co_(0.04)Mn_(0.04)O_(2).The addition of nanoparticles effectively bridges the void of SC-NCM,builds an ideal particle grading,and significantly raises the cost efficiency,as well as promotes the cycling stability and safety of the full cell.Remarkably,the layered/olivine mixture forms a perfect shield by lowering the surface area between the NCM cathode and electrolyte,hence mitigating side reactions and contributing to an incredibly thin and stable cathode/electrolyte interface.Furthermore,the thermodynamic stability of highly delithiated NCM is improved,as both the particle cracks and structural degradation are simultaneously postponed.Consequently,the maximum temperature of the single-crystal LiNi_(0.92)Co_(0.04)Mn_(0.04)O_(2)@LiFePO_(4)‖graphite pouch full cell is dramatically reduced from 599.4 to 351.4℃,and the full cell achieves 88.2%capacity retention after 800 cycles,demonstrating excellent thermal stability and cycling stability.This facile strategy provides a feasible technical reference for further exploiting the ultrahigh-capacity,highsafety,and long-life Ni-rich cathode for commercial application of lithium-ion batteries(LIBs). 展开更多
关键词 Single-crystal LiNi_(0.92)Co_(0.04)Mn_(0.04)O_(2) LiFePO_(4)nano-particles Ultrahigh voltage Thermal stability Cycling stability
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Simultaneous fluorescence and Compton scattering computed tomography based on linear polarization X-ray
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作者 zhi-Jun Chi Hong-Ze zhang +7 位作者 Jin Lin Xuan-Qi zhang Hao Ding Qi-Li Tian zhi zhang Ying-Chao Du Wen-Hui Huang Chuan-Xiang Tang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期41-50,共10页
Purpose To propose a method for simultaneous fluorescence and Compton scattering computed tomography by using linearly polarized X-rays.Methods Monte Carlo simulations were adopted to demonstrate the feasibility of th... Purpose To propose a method for simultaneous fluorescence and Compton scattering computed tomography by using linearly polarized X-rays.Methods Monte Carlo simulations were adopted to demonstrate the feasibility of the proposed method.In the simulations,the phantom is a polytetrafluoroethylene cylinder inside which are cylindrical columns containing aluminum,water,and gold(Au)-loaded water solutions with Au concentrations ranging between 0.5 and 4.0 wt%,and a parallel-hole collimator imaging geometry was adopted.The light source was modeled based on a Thomson scattering X-ray source.The phantom images for both imaging modalities were reconstructed using a maximumlikelihood expectation maximization algorithm.Results Both the X-ray fluorescence computed tomography(XFCT)and Compton scattering computed tomography(CSCT)images of the phantom were accurately reconstructed.A similar attenuation contrast problem for the different cylindrical columns in the phantom can be resolved in the XFCT and CSCT images.The interplay between XFCT and CSCT was analyzed,and the contrast-to-noise ratio(CNR)of the reconstruction was improved by correcting for the mutual influence between the two imaging modalities.Compared with K-edge subtraction imaging,XFCT exhibits a CNR advantage for the phantom.Conclusion Simultaneous XFCT and CSCT can be realized by using linearly polarized X-rays.The synergy between the two imaging modalities would have an important application in cancer radiation therapy. 展开更多
关键词 X-ray fluorescence computed tomography Compton scattering computed tomography Linear polarization Thomson scattering X-ray source Monte Carlo simulation
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Towards designing high mechanical performance low-alloyed wrought magnesium alloys via grain boundary segregation strategy:A review
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作者 zhi zhang Jinshu Xie +2 位作者 Jinghuai zhang Xu-Sheng Yang Ruizhi Wu 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第5期1774-1791,共18页
Low-alloyed magnesium(Mg)alloys have emerged as one of the most promising candidates for lightweight materials.However,their further application potential has been hampered by limitations such as low strength,poor pla... Low-alloyed magnesium(Mg)alloys have emerged as one of the most promising candidates for lightweight materials.However,their further application potential has been hampered by limitations such as low strength,poor plasticity at room temperature,and unsatisfactory formability.To address these challenges,grain refinement and grain structure control have been identified as crucial factors to achieving high performance in low-alloyed Mg alloys.An effective way for regulating grain structure is through grain boundary(GB)segregation.This review presents a comprehensive summary of the distribution criteria of segregated atoms and the effects of solute segregation on grain size and growth in Mg alloys.The analysis encompasses both single element segregation and multi-element co-segregation behavior,considering coherent interfaces and incoherent interfaces.Furthermore,we introduce the high mechanical performance low-alloyed wrought Mg alloys that utilize GB segregation and analyze the potential impact mechanisms through which GB segregation influences materials properties.Drawing upon these studies,we propose strategies for the design of high mechanical performance Mg alloys with desirable properties,including high strength,excellent ductility,and good formability,achieved through the implementation of GB segregation.The findings of this review contribute to advancing the understanding of grain boundary engineering in Mg alloys and provide valuable insights for future alloy design and optimization. 展开更多
关键词 Magnesium alloys Grain boundary segregation High strength High plasticity High formability
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Graphene-loaded nickel−vanadium bimetal oxides as hydrogen pumps to boost solid-state hydrogen storage kinetic performance of magnesium hydride
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作者 Dong-qiang GAO Fu-ying WU +4 位作者 zhi zhang Zi-chuan LU Ren ZHOU Hu ZHAO Liu-ting zhang 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2645-2657,共13页
To modify the thermodynamics and kinetic performance of magnesium hydride(MgH_(2))for solid-state hydrogen storage,Ni_(3)V_(2)O_(8)-rGO(rGO represents reduced graphene oxide)and Ni_(3)V_(2)O_(8)nanocomposites were pre... To modify the thermodynamics and kinetic performance of magnesium hydride(MgH_(2))for solid-state hydrogen storage,Ni_(3)V_(2)O_(8)-rGO(rGO represents reduced graphene oxide)and Ni_(3)V_(2)O_(8)nanocomposites were prepared by hydrothermal and subsequent heat treatment.The beginning hydrogen desorption temperature of 7 wt.%Ni_(3)V_(2)O_(8)-rGO modified MgH_(2)was reduced to 208℃,while the additive-free MgH_(2)and 7 wt.%Ni_(3)V_(2)O_(8)doped MgH_(2)appeared to discharge hydrogen at 340 and 226℃,respectively.A charging capacity of about 4.7 wt.%H_(2)for MgH_(2)+7 wt.%Ni_(3)V_(2)O_(8)-rGO was achieved at 125℃ in 10 min,while the dehydrogenated MgH_(2)took 60 min to absorb only 4.6 wt.%H_(2)at 215℃.The microstructure analysis confirmed that the in-situ generated Mg_(2)Ni/Mg_(2)N_(i)H_(4) and metallic V contributed significantly to the enhanced performance of MgH_(2).In addition,the presence of rGO in the MgH_(2)+7 wt.%Ni_(3)V_(2)O_(8)-rGO composite reduced particle aggregation tendency of Mg/MgH_(2),leading to improving the cyclic stability of MgH_(2)during 20 cycles. 展开更多
关键词 hydrogen storage properties MgH_(2) graphene-loaded Ni−V bimetal oxides catalytic mechanism
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Vascular endothelial growth factor pathway’s influence on bevacizumab efficacy in metastatic colorectal cancer treatment
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作者 Yuan Qin Fu-Yuan Ma +2 位作者 zhi zhang Chen-Hao Zhao Biao Huang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第11期4514-4517,共4页
In this article,an article published in the World Journal of Gastrointestinal Oncology,which focuses on whether the expression of programmed death-ligand 1(PD-L1)affects the effectiveness of chemotherapy regimens,incl... In this article,an article published in the World Journal of Gastrointestinal Oncology,which focuses on whether the expression of programmed death-ligand 1(PD-L1)affects the effectiveness of chemotherapy regimens,including bevacizumab,in treating patients with colorectal cancer(CRC).Through neutralization of vascular endothelial growth factor(VEGF),bevacizumab inhibits tumor angiogenesis,impairing neovascularization and thereby depriving the tumor of essential nutrients and oxygen.Conversely,PD-L1 binding to VEGF receptor 2 promotes angiogenesis,supporting tumor vasculature.The interplay between these pathways complicates the assessment of bevacizumab’s efficacy in cancer therapy,notably in CRC,where VEGF and PD-L1 significantly affect treatment response.This review examines metastatic CRC treatment strategies,focusing on bevacizumab’s mechanism of action and the role of PD-L1 in this therapeutic context. 展开更多
关键词 BEVACIZUMAB CHEMOTHERAPY Metastatic colorectal cancer PD-1/PD-L1 axis Therapeutic approach Vascular endothelial growth factor
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Clinicopathological analysis of small intestinal metastasis from extra-abdominal/extra-pelvic malignancy
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作者 zhi zhang Jing Liu +5 位作者 Peng-Fei Yu Hai-Rui Yang Jin-Yang Li zhi-Wei Dong Wei Shi Guo-Li Gu 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第10期4138-4145,共8页
BACKGROUND The metastatic tumors in the small intestine secondary to extra-abdominal/extrapelvic malignancy are extremely rare.However,the small intestine metastases are extremely prone to misdiagnosis and missed diag... BACKGROUND The metastatic tumors in the small intestine secondary to extra-abdominal/extrapelvic malignancy are extremely rare.However,the small intestine metastases are extremely prone to misdiagnosis and missed diagnosis due to the lack of specific clinical manifestations and examination methods,thus delaying its treatment.Therefore,in order to improve clinical diagnosis and treatment capabilities,it is necessary to summarize its clinical pathological characteristics and prognosis.AIM To summarize the clinicopathological characteristics of patients with small intestinal metastases from extra-abdominal/extra-pelvic malignancy,and to improve the clinical capability of diagnosis and treatment for rare metastatic tumors in the small intestine.METHODS The clinical data of patients with small intestinal metastases from extra-abdominal/extra-pelvic malignancy were retrieved and summarized,who admitted to and treated in the Air Force Medical Center,Chinese People’s Liberation Army.Then descriptive statistics were performed on the general conditions,primary tumors,secondary tumors in the small intestine,diagnosis and treatment processes,and prognosis.RESULTS Totally 11 patients(9 males and 2 females)were enrolled in this study,including 8 cases(72.3%)of primary lung cancer,1 case(9.1%)of malignant lymphoma of the thyroid,1 case(9.1%)of cutaneous malignant melanoma,and 1 case(9.1%)of testicular cancer.The median age at the diagnosis of primary tumors was 57.9 years old,the median age at the diagnosis of metastatic tumors in the small intestine was 58.81 years old,and the average duration from initial diagnosis of primary tumors to definite diagnosis of small intestinal metastases was 9 months(0-36 months).Moreover,small intestinal metastases was identified at the diagnosis of primary tumors in 4 cases.The small intestinal metastases were distributed in the jejunum and ileum,with such clinical manifestations as hematochezia(5,45.4%)and abdominal pain,vomiting and other obstruction(4,36.4%).In addition,2 patients had no obvious symptoms at the diagnosis of small intestinal metastases,and 5 patients underwent radical resection of small intestinal malignancies and recovered well after surgery.A total of 3 patients did not receive subsequent treatment due to advanced conditions.CONCLUSION Small intestinal metastases of extra-abdominal/extra-pelvic malignancy is rare with high malignancy and great difficulty in diagnosis and treatment.Clinically,patients with extra-abdominal/extra-pelvic malignancy should be alert to the occurrence of this disease,and their prognosis may be improved through active surgery combined with standard targeted therapy. 展开更多
关键词 Small intestinal METASTASES Clinicopathological features Prognostic analysis MALIGNANCY
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铁电极化增强C/Bi/Bi_(2)MoO_(6)复合材料光催化性能的研究——推荐一个综合化学实验
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作者 周鑫 张志 +1 位作者 杨赟 杨水金 《大学化学》 CAS 2024年第4期296-304,共9页
本文围绕环境问题设计了一个综合化学实验。制备了C/Bi/Bi_(2)MoO_(6)复合材料,并对其施加直流电压进行电极化处理,通过扫描电镜和X射线粉末衍射等表征得出电极化法不影响材料的形貌和组成结构,并且能有效增强复合材料的光催化降解活性... 本文围绕环境问题设计了一个综合化学实验。制备了C/Bi/Bi_(2)MoO_(6)复合材料,并对其施加直流电压进行电极化处理,通过扫描电镜和X射线粉末衍射等表征得出电极化法不影响材料的形貌和组成结构,并且能有效增强复合材料的光催化降解活性。本实验实现了化学、环境、能源与材料等多学科交叉融合,实验可操作性强且绿色环保。通过实验改进和仪器表征,激发学生的科研热情,培养创新思维和动手能力。 展开更多
关键词 光催化 铁电极化 综合化学实验 综合应用与创新能力
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Effect of Structural Configu ations on Mechanical and Shape Recovery Properties of Ni Ti Triply Periodic Minimal Surface Porous Structures
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作者 Shuaishuai Wei Bo Song +4 位作者 Lei zhang Xiaobo Wang Junxiang Fan zhi zhang Yusheng Shi 《Chinese Journal of Mechanical Engineering》 CSCD 2024年第6期303-319,共17页
Based on the advantages of triply periodic minimal surface(TPMS)porous structures,extensive research on NiTi shape memory alloy TPMS scaffolds has been conducted.However,the current reports about TPMS porous structure... Based on the advantages of triply periodic minimal surface(TPMS)porous structures,extensive research on NiTi shape memory alloy TPMS scaffolds has been conducted.However,the current reports about TPMS porous structures highly rely on the implicit equation,which limited the design flexibility.In this work,novel shell-based TPMS structures were designed and fabricated by laser powder bed fusion.The comparisons of manufacturability,mechanical properties,and shape recovery responses between traditional solid-based and novel shell-based TPMS structures were evaluated.Results indicated that the shell-based TPMS porous structures possessed larger Young's moduli and higher compressive strengths.Specifically,Diamond shell structure possessed the highest Young's moduli of 605.8±24.5MPa,while Gyroid shell structure possessed the highest compressive strength of 43.90±3.32 MPa.In addition,because of the larger specific surface area,higher critical stress to induce martensite transformation,and lower austenite finish temperature,the Diamond shell porous structure exhibited much higher shape recovery performance(only 0.1%residual strain left at pre-strains of 6%)than other porous structures.These results substantially uncover the effects of structural topology on the mechanical properties and shape recovery responses of NiTi shape memory alloy scaffolds,and confirm the effectiveness of this novel structural design method.This research can provide guidance for the structural design application of NiTi porous scaffolds in bone implants. 展开更多
关键词 NiTi shape memory alloy Porous structure Laser powder bed fusion Mechanical property Shape recovery property
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High-intensity spatial-mode steerable frequency up-converter toward on-chip integration
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作者 Haizhou Huang Huaixi Chen +7 位作者 Huagang Liu zhi zhang Xinkai Feng Jiaying Chen Hongchun Wu Jing Deng Wanguo Liang Wenxiong Lin 《Opto-Electronic Science》 2024年第4期12-20,共9页
Integrated photonic devices are essential for on-chip optical communication,optical-electronic systems,and quantum information sciences.To develop a high-fidelity interface between photonics in various frequency domai... Integrated photonic devices are essential for on-chip optical communication,optical-electronic systems,and quantum information sciences.To develop a high-fidelity interface between photonics in various frequency domains without disturbing their quantum properties,nonlinear frequency conversion,typically steered with the quadratic(χ2)process,should be considered.Furthermore,another degree of freedom in steering the spatial modes during theχ2 process,with unprecedent mode intensity is proposed here by modulating the lithium niobate(LN)waveguide-based inter-mode quasi-phasematching conditions with both temperature and wavelength parameters.Under high incident light intensities(25 and 27.8 dBm for the pump and the signal lights,respectively),mode conversion at the sum-frequency wavelength with sufficient high output power(−7–8 dBm)among the TM01,TM10,and TM00 modes is realized automatically with characterized broad temperature(ΔT≥8°C)and wavelength windows(Δλ≥1 nm),avoiding the previous efforts in carefully preparing the signal or pump modes.The results prove that high-intensity spatial modes can be prepared at arbitrary transparent wavelength of theχ2 media toward on-chip integration,which facilitates the development of chip-based communication and quantum information systems because spatial correlations can be applied to generate hyperentangled states and provide additional robustness in quantum error correction with the extended Hilbert space. 展开更多
关键词 integrated photonics LN waveguide sum-frequency generation spatial-mode steering on-chip integration
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Performance comparison of single-carrier and multi-carrier waveforms over terahertz wireless channels
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作者 Dongxuan He zhi zhang +3 位作者 Hao Lin Zuomin Wu Yingpei Huang Zhaocheng Wang 《Digital Communications and Networks》 CSCD 2024年第5期1297-1304,共8页
Terahertz(THz)wireless communication has been recognized as a powerful technology to meet the everincreasing demand of ultra-high rate services.In order to achieve efficient and reliable wireless communications over T... Terahertz(THz)wireless communication has been recognized as a powerful technology to meet the everincreasing demand of ultra-high rate services.In order to achieve efficient and reliable wireless communications over THz bands,it is extremely necessary to find an appropriate waveform for THz communications.In this paper,performance comparison of various single-carrier and multi-carrier waveforms over THz channels will be provided.Specifically,first,a system model for terahertz communication is briefly described,which includes amplifier nonlinearity,propagation characteristic,phase noise,etc.Then,the transceiver architectures related to both single-carrier and multi-carrier waveforms are presented,as well as their corresponding signal processing techniques.To evaluate the suitability of the waveforms,key performance metrics concerning power efficiency,transmission performance,and computational complexity are provided.Simulation results are provided to compare and validate the performance of different waveforms,which demonstrate the outstanding performance of Discrete-Fourier-Transform spread Orthogonal Frequency Division Multiplexing(DFT-s-OFDM)to THz communications when compared to Cyclic Prefix-OFDM(CP-OFDM)and other single-carrier waveforms. 展开更多
关键词 Terahertz communication RF imperfection Single-carrier waveform Multi-carrier waveform
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Technology of Extracting Kiwi Fruit Seed Oil with Ultrasonic-Assisted Enzyme and Response Surface Method 被引量:1
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作者 zhi zhang Mengting Pan Dongmin Liu 《Food and Nutrition Sciences》 2016年第9期807-816,共11页
Taken kiwi fruit as raw material, this paper extracted kiwi fruit seed oil with ultrasonic-assisted enzyme, researched the influence of factors such as liquid-to-solid ratio, granularity, type of enzyme, ultrasonic po... Taken kiwi fruit as raw material, this paper extracted kiwi fruit seed oil with ultrasonic-assisted enzyme, researched the influence of factors such as liquid-to-solid ratio, granularity, type of enzyme, ultrasonic power, treating time, enzymolysis temperature, enzymolysis time, pH and enzyme additive on oil extraction, and optimized the extracting technology of kiwi fruit seed oil with response surface method. The result shows that the best technical parameter is: material granularity: 60, liquid-to-solid ratio: 1:10 (g/mL), ultrasonic power: 400 W, treating time: 30 min, enzyme amount: 2.50%, pH: 9.2, enzymolysis temperature: 53&deg;C, enzymolysis time: 2.80 h;and the extracting ratio under such condition is 92.57%. 展开更多
关键词 Kiwi Fruit Seed Oil Ultrasonic Wave Aqueous Enzymatic Method
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Model Predictive Control for Cascaded H-Bridge PV Inverter with Capacitor Voltage Balance
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作者 Xinwei Wei Wanyu Tao +4 位作者 Xunbo Fu Xiufeng Hua zhi zhang Xiaodan Zhao Chen Qin 《Journal of Electronic Research and Application》 2024年第2期79-85,共7页
We designed an improved direct-current capacitor voltage balancing control model predictive control(MPC)for single-phase cascaded H-bridge multilevel photovoltaic(PV)inverters.Compared with conventional voltage balanc... We designed an improved direct-current capacitor voltage balancing control model predictive control(MPC)for single-phase cascaded H-bridge multilevel photovoltaic(PV)inverters.Compared with conventional voltage balanc-ing control methods,the method proposed could make the PV strings of each submodule operate at their maximum power point by independent capacitor voltage control.Besides,the predicted and reference value of the grid-connected current was obtained according to the maximum power output of the maximum power point tracking.A cost function was con-structed to achieve the high-precision grid-connected control of the CHB inverter.Finally,the effectiveness of the proposed control method was verified through a semi-physical simulation platform with three submodules. 展开更多
关键词 Model predictive control(MPC) Photovoltaic system Cascaded H-bridge(CHB)inverter Capacitor voltage balance
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2011—2017年天津市监狱服刑人员肺结核患者发现方式与发病率分析 被引量:1
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作者 张志 王薇 +1 位作者 张国钦 魏文亮 《结核病与肺部健康杂志》 2018年第4期275-278,共4页
目的分析天津市监狱系统服刑人员肺结核患者发现情况和变化趋势。方法收集2011—2017年天津市结核病登记管理系统中1280例监狱服刑人员肺结核患者登记数据,分析肺结核患者发现方式、发病率及其变化趋势。结果1280例肺结核患者中,通过入... 目的分析天津市监狱系统服刑人员肺结核患者发现情况和变化趋势。方法收集2011—2017年天津市结核病登记管理系统中1280例监狱服刑人员肺结核患者登记数据,分析肺结核患者发现方式、发病率及其变化趋势。结果1280例肺结核患者中,通过入监体检、肺结核普查和因症就诊3种发现方式分别确诊366例(28.6%)、540例(42.2%)和374例(29.2%)。入监体检方式发现患者构成比由2011年的15.2%(30/197)上升至2017年的62.5%(135/216),差异有统计学意义(χ2=157.22,P<0.01);普查方式发现患者构成比由2011年的35.5%(70/197)下降至2017年的26.4%(57/216),差异有统计学意义(χ2=16.33,P<0.01);因症就诊方式发现患者构成比由2011年的49.3%(97/197)下降至2017年的11.1%(24/216),差异有统计学意义(χ2=65.12,P<0.01)。天津市监狱服刑人员涂阳肺结核发病率由2011年的44.0/10万(9/20450)下降至2017年的9.8/10万(2/20452),差异有统计学意义(χ2=6.60,P=0.010)。结论采用主动(入监体检、普查)与被动(因症就诊)相结合的发现方式,天津市服刑人员肺结核疫情得到有效控制。其中主动发现方式相比传统被动发现方式对监狱服刑人员肺结核疫情控制具有更重要作用。 展开更多
关键词 结核 监狱 囚犯 发病率 横断面研究 传染病控制
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阿里地区牦牛血清生化指标检测 被引量:3
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作者 平措占堆 洛桑顿珠 +7 位作者 尼玛次仁 索朗多吉 巴多 旦巴 旦巴加参 支张 张强 巴桑旺堆 《现代农业科技》 2021年第20期174-177,共4页
以阿里地区4~5岁牦牛为试验对象,分析了牦牛的39项血清生化指标,完成了39项血清生化指标95%置信参考范围分析,同时比较了不同饲养模式下牦牛的血清生化指标。结果表明:阿里地区牦牛的乳酸脱氢酶、α-羟丁酸、渗透压等血清生化指标高,胱... 以阿里地区4~5岁牦牛为试验对象,分析了牦牛的39项血清生化指标,完成了39项血清生化指标95%置信参考范围分析,同时比较了不同饲养模式下牦牛的血清生化指标。结果表明:阿里地区牦牛的乳酸脱氢酶、α-羟丁酸、渗透压等血清生化指标高,胱抑素C、β-2微球蛋白、尿素氮/肌酐等血清生化指标低;舍饲牦牛总蛋白、间接胆红素、碱性磷酸酶、β-2微球蛋白等指标高于散养牦牛,差异显著(P<0.05);舍饲牦牛肌酸酶同工酶、二氧化碳、尿素以及尿素氮/肌酐等指标高于散养牦牛,差异极显著(P<0.01)。 展开更多
关键词 牦牛 血清生化指标 饲养模式 西藏阿里
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阿里牦牛经济性状相关遗传标记基因型频率研究 被引量:5
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作者 张强 洛桑顿珠 +7 位作者 鲜莉莉 平措占堆 索朗多吉 巴多 旦巴 旦巴加参 支张 巴桑旺堆 《西南农业学报》 CSCD 北大核心 2022年第5期1209-1215,共7页
【目的】进一步明确西藏阿里牦牛生态类群(Ali[AL])重要经济性状分子遗传改良潜力。【方法】利用SNaPshot基因分型技术对AL类群内7个已被证实与牦牛生长和泌乳经济性状显著相关的候选SNPs标记的基因型分布进行研究。【结果】在阿里牦牛... 【目的】进一步明确西藏阿里牦牛生态类群(Ali[AL])重要经济性状分子遗传改良潜力。【方法】利用SNaPshot基因分型技术对AL类群内7个已被证实与牦牛生长和泌乳经济性状显著相关的候选SNPs标记的基因型分布进行研究。【结果】在阿里牦牛群体内2个SNP位点(MyoD1_C1710T和ACSL1_G2409A)是中度多态位点(0.25<PIC<0.5),4个SNP位点(ACSL1_A2079T、Hesx1_T226C、TMEM-18_C1267T、TMEM-18_C4447T)为低度多态位点(0.25<PIC<0.5),另外Hesx1-G618C位点在全部个体中均为纯合子(G/G)。除Hesx1-G618C位点外,其他全部位点在阿里牦牛群体内均未显著偏离哈代温伯格平衡(P>0.05)。阿里牦牛群体内与生长相关的标记MyoD1_C1710T和TMEM18_C4447T位点均携带高频率的优势基因型。另外,有17.7419%的阿里牦牛个体在HesxI_T226C位点携带与牦牛12月龄体质量、体高和胸围相关的优势基因型(T/C),有11.2903%个体携带与牦牛产乳量和乳品质相关标记ACSL1_G2409A的优势基因型A/A。【结论】本研究结果表明阿里牦牛在多个已知经济性状相关SNP标记中携带高比例优势基因型,进一步明确了阿里牦牛分子选育遗传改良的潜力,同时为今后牦牛分子育种标记体系建立提供数据参考。 展开更多
关键词 阿里牦牛 经济性状 单核苷酸多态性 分子标记 优势基因型
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利用微卫星遗传标记评估5个西藏牦牛群体遗传多样性及群体结构 被引量:3
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作者 张强 洛桑顿珠 +10 位作者 巴桑旺堆 彭阳洋 俄广鑫 尼玛次仁 索朗多吉 巴多 旦巴 鲜莉莉 旦巴加参 支张 平措占堆 《中国畜牧兽医》 CAS 北大核心 2022年第6期2228-2238,共11页
【目的】评估当前西藏主要牦牛群体遗传多样性,梳理不同地区群体间遗传结构,明确西藏5个牦牛群体(阿里牦牛、斯布牦牛、娘亚牦牛、类乌齐牦牛和帕里牦牛)的保种情况和种群间系统发育关系。【方法】利用13个微卫星标记(SSR)对5个牦牛群... 【目的】评估当前西藏主要牦牛群体遗传多样性,梳理不同地区群体间遗传结构,明确西藏5个牦牛群体(阿里牦牛、斯布牦牛、娘亚牦牛、类乌齐牦牛和帕里牦牛)的保种情况和种群间系统发育关系。【方法】利用13个微卫星标记(SSR)对5个牦牛群体共计195个个体进行基因分型,并对各群体的等位基因数量、基因杂合度、多态信息含量及群体间遗传距离等遗传参数进行评估。【结果】阿里牦牛群体等位基因数最多(6.43),类乌齐牦牛等位基因数最少(5.00);观测杂合度范围为0.5311(娘亚牦牛)~0.5995(类乌齐牦牛)。各群体内偏离Hardy-Weinberg平衡的位点数为5(类乌齐牦牛)~9(阿里牦牛)个;群体内近交系数最高为0.172(阿里牦牛),且4个群体(阿里牦牛、娘亚牦牛、斯布牦牛和帕里牦牛)存在显著近交风险(P<0.05)。从遗传结构来看,所有群体间均为显著遗传分歧(P<0.05),STRUCTURE分析结果显示,5个牦牛群体划分为3个簇,其中阿里牦牛较其他牦牛群体具有更为丰富的遗传背景。系统发育树结果表明,不同群体间系统发育关系相对独立,且与种群栖息地分布不一致。主坐标分析(PCoA)结果显示,不同群体间部分个体存在较近亲缘关系,表明不同群体间存在遗传物质交流。【结论】5个西藏牦牛群体具有丰富的遗传多样性水平,且种群系统发育关系相对独立,但多数群体存在群体事件风险。本研究不仅有助于明确西藏牦牛地方种群遗传多样性水平,同时可为今后的保种策略提升提供理论参考。 展开更多
关键词 西藏牦牛 微卫星标记 遗传多样性 群体结构
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西藏阿里地区牦牛生态类群分子遗传多样性研究 被引量:3
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作者 平措占堆 洛桑顿珠 +8 位作者 鲜莉莉 尼玛次仁 索朗多吉 巴多 旦巴 旦巴加参 支张 张强 巴桑旺堆 《中国草食动物科学》 CAS 2021年第5期12-17,共6页
利用多种分子标记鉴定西藏阿里牦牛生态类群遗传多样性状态,以期为阿里牦牛遗传资源的保护、开发和利用奠定理论基础。利用13个微卫星标记位点及线粒体D-Loop高变区分别对69头和50头西藏阿里牦牛进行了遗传多样性评估。结果显示,在13个... 利用多种分子标记鉴定西藏阿里牦牛生态类群遗传多样性状态,以期为阿里牦牛遗传资源的保护、开发和利用奠定理论基础。利用13个微卫星标记位点及线粒体D-Loop高变区分别对69头和50头西藏阿里牦牛进行了遗传多样性评估。结果显示,在13个微卫星位点中共检测出124个等位基因,其中TGL122和ILSTSO50位点的复等位基因数最多(15个),BGR3001位点的等位基因数最少(1个);从群体上来看,阿里牦牛群体的平均观测杂合度(Ho±SD)为0.5790±0.0139,其中11个位点偏离哈代-温伯格平衡,且近交系数(FIS)为0.192(P<0.05);虽然依据IAM和TPM模型暗示该群体存在显著瓶颈效应(P<0.05),但模式迁移图形仍为L-型分布;阿里牦牛线粒体D-loop区序列的794 bp片段范围内,共计鉴定到80个变异位点,同时构建得到38个单倍型,全部单倍型分为2个母系支系;群体平均单倍型多样性(Hd)为0.941,平均核苷酸多样性(Pi)为0.01600。说明目前阿里牦牛群体内仍具有较丰富的母系遗传多样性,但群体整体可能存在近交和经历瓶颈效应的风险,故而需要进一步加强该群体保种工作,同时优化或改变现有保种模式和方案。 展开更多
关键词 西藏 牦牛 遗传多样性 线粒体DNA 微卫星
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