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Optoelectronics Letters 2024年第5期20卷 265-271页

作者： QI Hexin ZHOU Xuefang ZHANG Yinghui yang Guowei BI Meihua HU Miao School of Communication Engineering Hangzhou Dianzi UniversityHangzhou 310018China

A switchable and tunable multi-wavelength Brillouin erbium-doped fiber laser(MWBEFL) is designed and experimentally demonstrated. A Sagnac loop filter is employed as the switcher to obtain the double Brillouin frequency shift(BFS) of 0.172 nm(~20 GHz) and the quadruple BFS of 0.35 nm(~40 GHz). The working principles of the proposed laser are theoretically analyzed. The experimental results show that up to 8 Stokes lines with a wavelength interval of 0.172 nm can be obtained. When the Sagnac loop filter is used, two different output spectra with wavelength interval of 0.35 nm are obtained by adjusting the polarization controller(PC) and the optical signal-to-noise ratio(OSNR) is greater than 33 dB. By adjusting the Brillouin pump(BP) wavelength to investigate the tunability of the fiber laser, the output of 2—5 laser channels can be realized corresponding to 20 nm wavelength range. This approach is simple and can be employed for the microwave generation of other frequency ranges subject to the filtering shift of the Sagnac loop.

关键词： fiber laser filter

KLF4 Inhibits the Activation of Human Hepatic Stellate Cell In Vitro

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Current Medical Science 2024年第3期44卷 512-518页

作者： Xing-yu yang Zhe CHEN Jun TAN Yin-kai XUE Hai ZHENG department of Emergency Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China department of Thoracic Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an710061China department of Thoracic Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China

Objective Hepatic stellate cells(HSCs)play a crucial role in liver ***-stage liver fibrosis is reversible and intimately associated with the state of ***-like factor 4(KLF4)plays a pivotal role in a wide array of physiological and pathological *** study aimed to investigate the effect of KLF4 on the proliferation,apoptosis and phenotype of quiescent HSCs Methods We designed a KLF4 lentiviral vector and a KLF4 siRNA lentiviral vector,to upregulate and silence KLF4 expression in human HSC LX-2 cells via *** proliferation was assessed using the CCK-8 *** cytometry was used to detect the cell cycle distribution and apoptosis *** blotting was used to determine the levels of some quiescence and activation markers of HSCs Results Overexpression of KLF4 significantly increased the levels of E-cadherin and ZO-1,which are quiescent HSC markers,while significantly decreased the levels of N-cadherin and a-SMA,known activated HSC *** contrast,cell proliferation and apoptosis rates were elevated in LX-2 cells in which KLF4 expression was silenced Conclusion KLF4 inhibits the proliferation and activation of human LX-2 *** might be a key regulatory protein in the maintenance of HSC quiescence and may serve as a target for the inhibition of hepatic fibrosis.

关键词： Kruppel-like factor 4 hepatic stellate cells LX-2 cells liver fibrosis

Research on Recommendation Algorithms Based on Cloud Models in Probabilistic Linguistic Environments

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Journal of Systems Science and Information 2024年第1期12卷 96-112页

作者： Peng yang Xifeng MA Meng WEI Chunsheng CUI Libin CHE College of Computer and Information Engineering Henan University of Economics and LawZhengzhou 450046China

To solve the problem that the traditional cloud model can't directly process the textual review information in the recommendation algorithm,this paper combines the merits of the cloud model in transforming qualitative and quantitative knowledge with the multi-granularity advantages of probabilistic linguistic term sets in representing uncertain information,and proposes a recommendation algorithm based on cloud model in probabilistic language ***,this paper quantifies the attributes in the review text based on the probabilistic linguistic term ***,the maximum deviation method is used to determine the weight of each attribute in the evaluation information of the product to be recommended,and the comprehensive evaluation number and attribute weight are converted into the digital characteristic value of the cloud model by using the backward cloud ***,the products are recommended and sorted based on the digital characteristic value of the cloud *** algorithm is applied to the recommendation of 10 hotels,and the results show that the method is effective and practical,enriching the application of cloud models in the recommendation field.

关键词： recommendation algorithm cloud model probabilistic linguistic term set text reviews

A_(2)B_(7)-type La-Mg-Ni alloys prepared by Mg thermal diffusion for improved hydrogen storage performance

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Rare Metals 2024年第7期43卷 3260-3272页

作者： Yong-Xi Zhang Guan-Jiu Wu Jing Gu Hong-Xing Kang Yuan Li Di Zhou Wen-feng Wang Lu Zhang Shu-Min Han Hebei Key Laboratory of Applied Chemistry School of Environmental and Chemical EngineeringYanshan UniversityQinhuangdao 066004China department of Chemistry and Biochemistry San Diego State UniversitySan DiegoCA92182-1030USA State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

A novel approach based on thermal diffusion was used to achieve controllable Mg content in A_(2)B_(7)-type La-Mg-Ni-based *** formation mechanism of the A_(2)B_(7)-type phase as a result of the thermal diffusion process and the effect of Mg content on hydrogen storage performance were investigated.X-ray diffraction(XRD)patterns and Rietveld refinement results showed that increased Mg transformed the LaNi_(5)phase in the La_(0.74)Sm_(0.03)Y_(0.23)Ni_(4.32)Al_(0.04)precursor alloy into a superlattice *** electron microscopy(SEM)images showed that Mg was evenly distributed in the alloy *** in the superlattice significantly inhibited the phase decomposition of the superlattice structure during the hydrogen absorption/desorption *** A_(2)B_(7)-type La_(0.57)Sm_(0.02)Y_(0.18)Mg_(0.23)Ni_(3.38)Al_(0.03)alloy composed of Gd_(2)Co_(7)and Ce_(2)Ni_(7)phases was successfully *** pressure-composition isotherm profiles showed that the alloy had a hydrogen storage capacity as high as 1.73 wt%,with good cycling *** 50 cycles of hydrogen absorption/desorption,the alloy retained a hydrogen storage capacity of 1.45 wt%,with a capacity retention rate of up to 84.28%.The Mg thermal diffusion process thus provides a new approach for the controlled preparation of La-Mg-Ni-based alloys.

关键词： La-Mg-Ni-based hydrogen storage alloy A_(2)B_(7)-type superlattice alloy Mg thermal diffusion process Phase transformation Hydrogen storage property

Grain boundary-induced drastic sensing performance enhancement of Fe_(2)O_(3) gas sensors for acetone

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Rare Metals 2024年第9期43卷 4412-4424页

作者： Tian-Jun Hu Yi-Fan Li Yu-Zhu Tian Ying Wang Ya-Ru Chen Jun-Ming Zhang Er-Gui Luo Jian-feng Jia Key Laboratory of Magnetic Molecules&Magnetic Information Materials Ministry of Education School of Chemical and Material ScienceShanxi Normal UniversityTaiyuan 030032China

Exploring the structure-activity relationship between the performance of gas sensors and the structure of semiconductor metal oxide(SMO)nanomaterials is crucial for understanding and designing gas-sensing materials and overcoming the application limitations of SMO-based gas *** of a single SMO microstructure provides a promising solution to address this scientific problem due to its controllable *** this study,we control the grain boundary(GB)density of Fe_(2)O_(3)nanomaterials using a simple solvothermal *** have similar chemical compositions and crystal phases,providing an ideal platform for studying the influence of the GB density on the gas-sensing ***-sensing tests showed that the Fe_(2)O_(3)-1 sensor with medium GB density and the Fe_(2)O_(3)-2 sensor with high GB density had higher sensitivity and selectivity than the Fe_(2)O_(3)-0 sensors with low GB density before reaching the optimal operating ***,when the GB density increased,the response to acetone decreased slightly,whereas the optimal operating temperature *** work highlights the unique performance of the GB density in enhancing the gas sensitivity of a single SMO.

关键词： Semiconductor metal oxide(SMO) Grain boundary(GB)density Oxygen adsorption Charge transfer Gas sensors

Porous organic cages as a novel platform for second harmonic generation

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Science China Chemistry 2024年第11期67卷 3669-3674页

作者： feng Shui Yunqin Zhang Mao Yi Xiongli Liu Lin Li Shuo Zhang Yongshen Zheng Yongtao Yao Qiao Zhao Baiyan Li Xianhe Bu School of Materials Science and Engineering National Institute for Advanced Materials TKL of Metal and Molecule-Based Material Chemistry Nankai University National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of Technology

Second harmonic generation(SHG) is one of the most extensively applied nonlinear optical phenomena. Compared to traditional inorganic SHG materials, organic SHG materials, including non-centrosymmetric small molecular crystals and organic polymers, have been extensively explored for SHG optics due to their advantageous properties, including high light-induced damage threshold, ultrafast response speed, high polarization ratio, wide transparency range, and elevated dielectric constant. However,in organic SHG materials, most small molecular crystals often show poor thermal stability(der high temperatures. On the other hand, the difficulty in the growth of large-size crystals as well as the disorderly array of chromospheres on polymer chains associated with organic polymers have hindered their widespread application in SHG due to the requirements of processability and ***, it is significantly necessary to develop novel organic SHG material with high thermal stability, large-size crystals,excellent processability, high homogeneity, and a well SHG effect. In the contribution, we developed herein porous organic cages(POCs) as a novel platform for SHG optics. Thanks to its inherent macromolecular composition and zero-dimensional discrete structures, POCs can not only solve the instability problem of small molecule crystals but also overcome the drawbacks in growing large-size crystals for organic polymer. The obtained two POCs with chiral asymmetric centers(CPOC-R-5 and CPOCS-7) display advantageous features for SHG optics including well SHG performance, large-size crystal(5 mm×3 mm×1 mm),high thermal stability(≥250 °C), wide transparency window(750–2,000 nm) and high polarization ratio(up to 94.5%). This work thus develops POCs as a new platform toward the construction of organic NLO materials with the potential application in sorts of SHG optics.

关键词： porous organic cages second harmonic generation novel SHG platform high thermal stability large-size single crystal

High performance receiving and processing technology in satellite beam hopping communication

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Journal of Systems Engineering and Electronics 2024年第4期35卷 815-828页

作者： ZHAI Shenghua HUI Tengfei GONG Xianfeng ZHANG Zehui GAO Xiaozheng yang Kai School of Communication Engineering Xi’Dian UniversityXian 710126China CAST(China Academy of Space Technology)-Xi’an Institute of Space Radio Technology Xi’an 710010China School of Cyberspace Science and Technology Beijing Institute of TechnologyBeijing 100081China School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

Beam-hopping technology has become one of the major research hotspots for satellite communication in order to enhance their communication capacity and ***,beam hopping causes the traditional continuous time-division multiplexing signal in the forward downlink to become a burst signal,satellite terminal receivers need to solve multiple key issues such as burst signal rapid synchronization and high-per-formance ***,this paper analyzes the key issues of burst communication for traffic signals in beam hopping sys-tems,and then compares and studies typical carrier synchro-nization algorithms for burst ***,combining the requirements of beam-hopping communication systems for effi-cient burst and low signal-to-noise ratio reception of downlink signals in forward links,a decoding assisted bidirectional vari-able parameter iterative carrier synchronization technique is pro-posed,which introduces the idea of iterative processing into car-rier *** at the technical characteristics of communication signal carrier synchronization,a new technical approach of bidirectional variable parameter iteration is adopted,breaking through the traditional understanding that loop struc-tures cannot adapt to low signal-to-noise ratio burst ***,combining the DVB-S2X standard physical layer frame format used in high throughput satellite communication systems,the research and performance simulation are *** results show that the new technology proposed in this paper can significantly shorten the carrier synchronization time of burst signals,achieve fast synchronization of low signal-to-noise ratio burst signals,and have the unique advantage of flexible and adjustable parameters.

关键词： beam-hopping high throughput satellite high per-formance reception processing

Thirty-year trends of anxiety disorders among adolescents based on the 2019 Global Burden of Disease Study

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General Psychiatry 2024年第2期37卷 242-253页

作者： Xiaohan Liu Fan yang Ning Huang Shan Zhang Jing Guo School of Public Health Peking University Health Science CenterNo.38 Xueyuan RdHaidian DistrictBeijingChina

Background Anxiety disorders are the most common psychiatric problems,affecting approximately 1 in 12 children and 1 in 4 *** the incidence,burden and correlated risks of anxiety disorders among children and adolescents can help identify areas of success,stagnation and emerging threats,thereby facilitating effective improvement *** To estimate the incidence and burden trends of anxiety disorders in children and adolescents from 1990 to 2019 in 204 countries and compare the incidence and disease burden in different *** examine the association between anxiety disorders and social indicators(healthcare access and quality of life).Methods Data were obtained from the Global Burden of Disease Study *** age-standardised incidence rates(ASIRs)and disability-adjusted life years(DALYs)were reported to assess the burden of anxiety disorders,and the estimated annual percentage change was calculated to quantify the temporal ***’s correlation was used to investigate country-level risk factors for incidence and *** Globally,there were 932 million incident cases of anxiety disorders in children and adolescents,739.29 per 100000 ASIRs and 380.62 million DALYs in *** 1990 to 2019,the estimated annual percentage change of incidence of anxiety disorders decreased by 2.2%.Significant variations were observed in the age-standardised burden rate and the changing trend of anxiety disorders among *** reported the highest ASIR of anxiety disorders,while Mexico had the largest increase rate of *** 2019,Portugal reported the highest number of DALYs(1001.71 million),and India(212.09 million)reported the lowest number of *** burden of anxiety disorders was positively correlated with the average number of psychiatrists,psychologists and nurses in the mental health sector(per 100000),and quality of life and the correlation coefficients were 0.58,0.67,0.43 and 0.53,*** The incide

关键词： disorders adolescent nurse

The surface electron transfer strategy promotes the hole of PDI release and enhances emerging organic pollutant degradation

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Journal of Semiconductors 2024年第10期45卷 84-91页

作者： Yunchuan yang Dongyu Wang Jisheng Geng Jun Liu Jun Wang State Key Laboratory of Environmental−Friendly Energy Materials School of Materials and ChemistrySouthwest University of Science and TechnologyMianyang 621010China Tianfu Institute of Research and Innovation Southwest University of Science and TechnologyChengdu 610213China Guangdong−Hong Kong Joint Laboratory for Water Security Center for Water ResearchAdvanced Institute of Natural SciencesBeijing Normal University at ZhuhaiZhuhai 519087China

In semiconductor photocatalysts,the easy recombination of photogenerated carriers seriously affects the application of photocatalytic materials in water *** solve the serious problem of electron−hole pair recombination in perylene diimide(PDI)organic semiconductors,we loaded ferric hydroxyl oxide(FeOOH)on PDI materials,successfully prepared novel FeOOH@PDI photocatalytic materials,and constructed a photo-Fenton *** system was able to achieve highly efficient degradation of BPA under visible light,with a degradation rate of 0.112 min^(−1)that was 20 times higher than the PDI system,and it also showed universal degradation performances for a variety of emerging organic pollutants and anti-interference *** mechanism research revealed that the FeOOH has the electron trapping property,which can capture the photogenerated electrons on the surface of PDI,effectively reducing the compounding rate of photogenerated carriers of PDI and accelerating the iron cycling and H2O2 activation on the surface of FeOOH at the same *** work provides new insights and methods for solving the problem of easy recombination of carriers in semiconductor photocatalysts and degrading emerging organic pollutants.

关键词： perylene diimide organic semiconductors emerging pollutants surface electron transfer strategy photo-Fenton

MyoG基因多态性与瑶山鸡体尺、屠宰性能及肉质性状的关联分析

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南方农业学报 2021年第10期52卷 2887-2895页

作者：杨德凤李维刘洋张芸龚俞张蓝艺陈颖林家栋张福平唐继高贵州大学动物科学学院/高原山地动物遗传育种与繁殖教育部重点实验室/贵州省动物遗传育种与繁殖重点实验室贵阳550025 贵州大学科研鸡场贵阳550025 贵州大学家禽研究所贵阳550025 贵州省畜禽遗传资源管理站贵阳550001 贵州农业职业学院贵阳551400 贵州省畜牧兽医研究所贵阳550005

【目的】探究肌细胞生成素基因(MyoG)多态性与瑶山鸡体尺、屠宰性能及肉质性状的关联性,从分子标记角度对瑶山鸡进行选育,更好地保护和开发利用瑶山鸡,同时为家禽MyoG基因研究提供参考依据。【方法】以150日龄出栏的健康瑶山鸡为研究对... 详细信息

【目的】探究肌细胞生成素基因(MyoG)多态性与瑶山鸡体尺、屠宰性能及肉质性状的关联性,从分子标记角度对瑶山鸡进行选育,更好地保护和开发利用瑶山鸡,同时为家禽MyoG基因研究提供参考依据。【方法】以150日龄出栏的健康瑶山鸡为研究对象,通过PCR扩增产物直接测序对瑶山鸡MyoG基因多态性进行检测,利用DNAStar对测序结果进行比对分析以确定MyoG基因SNP位点,通过RNAfold对瑶山鸡MyoG基因突变前后的mRNA二级结构进行预测,并以SPSS 18.0分析SNP位点与瑶山鸡体尺、屠宰性能及肉质性状的相关性。【结果】在瑶山鸡MyoG基因第3外显子上发现1个SNP位点(T17C位点),属于同义突变,存在3种基因型(CC型、CT型和TT型);T为优势等位基因,CT为优势基因型;有效等位基因数(Ne)接近2.00;多态信息含量(PIC)为0.35,呈中度多态(0.250.05)。MyoG基因T17C位点突变致使其mRNA二级结构发生改变,进而导致其最小自由能由-452.60kcal/mol降至-465.24 kcal/mol。不同基因型瑶山鸡生长、屠宰性能及肉质性状间的相关分析结果显示,3种基因型瑶山鸡在体尺、屠宰性能及肉质性状间的相关性大部分呈现相同规律,其中胸宽与胸深在不同基因型瑶山鸡中均呈极显著正相关(P<0.01)。【结论】瑶山鸡MyoG基因T17C位点存在3种基因型,属于同义突变,并未引起氨基酸及其蛋白结构和功能的明显变化,但其多态性对瑶山鸡体尺性状、屠宰性能和肉质性状有一定影响,因此可作为瑶山鸡分子选育的候选遗传标记。

关键词：瑶山鸡肌细胞生成素基因(MyoG) 多态性体尺性状屠宰性能肉质性状