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Achieving Ultra-Broad Microwave Absorption Bandwidth Around Millimeter-Wave Atmospheric Window Through an Intentional Manipulation on Multi-Magnetic Resonance Behavior
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作者 Chuyang liu Lu Xu +6 位作者 Xueyu Xiang Yujing Zhang li zhou Bo Ouyang Fan Wu Dong‑Hyun Kim Guangbin Ji 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期291-307,共17页
The utilization of electromagnetic waves is rapidly advancing into the millimeter-wave frequency range,posing increasingly severe challenges in terms of electromagnetic pollution prevention and radar stealth.However,e... The utilization of electromagnetic waves is rapidly advancing into the millimeter-wave frequency range,posing increasingly severe challenges in terms of electromagnetic pollution prevention and radar stealth.However,existing millimeter-wave absorbers are still inadequate in addressing these issues due to their monotonous magnetic resonance pattern.In this work,rare-earth La^(3+)and non-magnetic Zr^(4+)ions are simultaneously incorporated into M-type barium ferrite(BaM)to intentionally manipulate the multi-magnetic resonance behavior.By leveraging the contrary impact of La^(3+)and Zr^(4+)ions on magnetocrystalline anisotropy field,the restrictive relationship between intensity and frequency of the multi-magnetic resonance is successfully eliminated.The magnetic resonance peak-differentiating and imitating results confirm that significant multi-magnetic resonance phenomenon emerges around 35 GHz due to the reinforced exchange coupling effect between Fe^(3+)and Fe^(2+)ions.Additionally,Mosbauer spectra analysis,first-principle calculations,and least square fitting collectively identify that additional La^(3+)doping leads to a profound rearrangement of Zr^(4+)occupation and thus makes the portion of polarization/conduction loss increase gradually.As a consequence,the La^(3+)-Zr^(4+)co-doped BaM achieves an ultra-broad bandwidth of 12.5+GHz covering from 27.5 to 40+GHz,which holds remarkable potential for millimeter-wave absorbers around the atmospheric window of 35 GHz. 展开更多
关键词 Microwave absorption Ultra-broad bandwidth M-type barium ferrite Magnetocrystalline anisotropy field Multimagnetic resonance
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Design,preparation,microstructure and mechanical property of the lightweight radiation-shielding Mg-Ta-Al composites basing differential temperature hot rolling
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作者 Wenbo Luo Songya Feng +7 位作者 Xiuzhu Han li zhou Qinke Kong Zhiyong Xue Jianzhao Wang Mei Zhan Xianhua Chen Fusheng Pan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第6期2433-2446,共14页
A novel lightweight,radiation-shielding Mg-Ta-Al layered metal-matrix composite(LMC)was successful designed by doping the extremely refractory metal(Ta)into Mg sheets.These Mg-based LMCs sheets shows excellent radiati... A novel lightweight,radiation-shielding Mg-Ta-Al layered metal-matrix composite(LMC)was successful designed by doping the extremely refractory metal(Ta)into Mg sheets.These Mg-based LMCs sheets shows excellent radiation-dose shield effect,about 145 krad·a^(−1),which is about 17 times of traditional Mg alloy,while its surface density is only about 0.9 g·cm^(−2),reducing by 60%than that of pure Ta.The quantitate relationship between radiation-dose and the materials’thickness was also confirmed to the logistic function when the surface density is in the range of 0.6-1.5 g·cm^(−2).Meantime,the rolling parameters,interface microstructure and mechanical properties in both as-rolled and annealing treated samples were evaluated.The sheets possess a special dissimilar atoms diffusion transitional zone containing an obvious inter-diffusion Mg-Al interface and the unique micro-corrugated Ta-Al interface,as well as a thin Al film with a thickness of about 10μm.The special zone could reduce the stress concentration and enhance the strength of Mg-Ta-Al LMCs.The interface bonding strength reaches up to 54-76 MPa.The ultimate tensile strength(UTS)and yield strength(TYS)of the Mg-Ta-Al sheet were high to 413 MPa and 263 MPa,respectively,along with an elongation of 5.8%.The molecular dynamics(MD)analysis results show that the two interfaces exhibit different formation mechanism,the Mg-Al interface primarily depended on Mg/Al atoms diffusion basing point defects movement,while the Ta-Al interface with a micro-interlock pining shape formed by close-packed planes slipping during high temperature strain-induced deformation process. 展开更多
关键词 Dissimilar metals composites Mg based alloys Radiation shielding Hot rolling LIGHTWEIGHT
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A highly reliable encoding and decoding communication framework based on semantic information
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作者 Yichi Zhang Haitao Zhao +4 位作者 Kuo Cao li zhou Zhe Wang Yueling liu Jibo Wei 《Digital Communications and Networks》 SCIE CSCD 2024年第3期509-518,共10页
Increasing research has focused on semantic communication,the goal of which is to convey accurately the meaning instead of transmitting symbols from the sender to the receiver.In this paper,we design a novel encoding ... Increasing research has focused on semantic communication,the goal of which is to convey accurately the meaning instead of transmitting symbols from the sender to the receiver.In this paper,we design a novel encoding and decoding semantic communication framework,which adopts the semantic information and the contextual correlations between items to optimize the performance of a communication system over various channels.On the sender side,the average semantic loss caused by the wrong detection is defined,and a semantic source encoding strategy is developed to minimize the average semantic loss.To further improve communication reliability,a decoding strategy that utilizes the semantic and the context information to recover messages is proposed in the receiver.Extensive simulation results validate the superior performance of our strategies over state-of-the-art semantic coding and decoding policies on different communication channels. 展开更多
关键词 Semantic information Semantic encoding method Context-based decoding method
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Effects of Abscisic Acid on Cold Resistance in Digitaria sanguinalis(L.)Scop.
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作者 Rongbo zhou Yihong HU +3 位作者 li zhou Jie PENG Fan XIE Chenzhong JIN 《Agricultural Biotechnology》 2024年第1期15-16,19,共3页
[Objectives]This study was conducted to detect the protective effect of abscisic acid on chilling injury of Digitaria sanguinalis(L.)Scop,and whether this effect is related to antioxidant enzymes and osmotic adjustmen... [Objectives]This study was conducted to detect the protective effect of abscisic acid on chilling injury of Digitaria sanguinalis(L.)Scop,and whether this effect is related to antioxidant enzymes and osmotic adjustment.[Methods]D.sanguinalis plants were sprayed with abscisic acid solution,and exposed to cold stress at 15℃for 3 d after one day and then at 5℃for 25 to 30 d in a growth chamber.The changes of plant osmotic potential under this treatment were detected.[Results]Under low temperature stress,the osmotic potential of plants in the abscisic acid treatment and the control increased,but the osmotic potential level of the abscisic acid treatment plants was lower.The SOD activity of plants in the ABA treatment and the control decreased under low temperature stress.Under low temperature stress,the activity of catalase and peroxidase in ABA-treated plants was higher than that in control plants.[Conclusions]This study provides a theoretical basis for the impact of abscisic acid on the physiological response of D.sanguinalis to cold injury. 展开更多
关键词 Digitaria sanguinalis Abscisic acid CAT POD ROS SOD
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Calcitriol attenuates liver fibrosis through hepatitis C virus nonstructural protein 3-transactivated protein 1-mediated TGF β1/Smad3 and NF-κB signaling pathways 被引量:1
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作者 liu Shi li zhou +13 位作者 Ming Han Yu Zhang Yang Zhang Xiao-Xue Yuan Hong-Ping Lu Yun Wang Xue-liang Yang Chen liu Jun Wang Pu liang Shun-Ai liu Xiao-Jing liu Jun Cheng Shu-Mei lin 《World Journal of Gastroenterology》 SCIE CAS 2023年第18期2798-2817,共20页
BACKGROUND Hepatic fibrosis is a serious condition,and the development of hepatic fibrosis can lead to a series of complications.However,the pathogenesis of hepatic fibrosis remains unclear,and effective therapy optio... BACKGROUND Hepatic fibrosis is a serious condition,and the development of hepatic fibrosis can lead to a series of complications.However,the pathogenesis of hepatic fibrosis remains unclear,and effective therapy options are still lacking.Our group identified hepatitis C virus nonstructural protein 3-transactivated protein 1(NS3TP1) by suppressive subtractive hybridization and bioinformatics analysis,but its role in diseases including hepatic fibrosis remains undefined.Therefore,additional studies on the function of NS3TP1 in hepatic fibrosis are urgently needed to provide new targets for treatment.AIM To elucidate the mechanism of NS3TP1 in hepatic fibrosis and the regulatory effects of calcitriol on NS3TP1.METHODS Twenty-four male C57BL/6 mice were randomized and separated into three groups,comprising the normal,fibrosis,and calcitriol treatment groups,and liver fibrosis was modeled by carbon tetrachloride(CCl4).To evaluate the level of hepatic fibrosis in every group,serological and pathological examinations of the liver were conducted.TGF-β1 was administered to boost the in vitro cultivation of LX-2 cells.NS3TP1,α-smooth muscle actin(α-SMA),collagen I,and collagen Ⅲ in every group were examined using a Western blot and real-time quantitative polymerase chain reaction.The activity of the transforming growth factor beta 1(TGFβ1)/Smad3 and NF-κB signaling pathways in each group of cells transfected with pcDNA-NS3TP1 or siRNA-NS3TP1 was detected.The statistical analysis of the data was performed using the Student’s t test.RESULTS NS3TP1 promoted the activation,proliferation,and differentiation of hepatic stellate cells(HSCs)and enhanced hepatic fibrosis via the TGFβ1/Smad3 and NF-κB signaling pathways,as evidenced by the presence of α-SMA,collagen I,collagen Ⅲ,p-smad3,and p-p65 in LX-2 cells,which were upregulated after NS3TP1 overexpression and downregulated after NS3TP1 interference.The proliferation of HSCs was lowered after NS3TP1 interference and elevated after NS3TP1 overexpression,as shown by the luciferase assay.NS3TP1 inhibited the apoptosis of HSCs.Moreover,both Smad3 and p65 could bind to NS3TP1,and p65 increased the promoter activity of NS3TP1,while NS3TP1 increased the promoter activity of TGFβ1 receptor I,as indicated by coimmunoprecipitation and luciferase assay results.Both in vivo and in vitro,treatment with calcitriol dramatically reduced the expression of NS3TP1.Calcitriol therapy-controlled HSCs activation,proliferation,and differentiation and substantially suppressed CCl4-induced hepatic fibrosis in mice.Furthermore,calcitriol modulated the activities of the above signaling pathways via downregulation of NS3TP1.CONCLUSION Our results suggest that calcitriol may be employed as an adjuvant therapy for hepatic fibrosis and that NS3TP1 is a unique,prospective therapeutic target in hepatic fibrosis. 展开更多
关键词 Nonstructural protein 3-transactivated protein 1 CALCITRIOL Liver fibrosis Hepatic stellate cells Mouse model TGFβ1/Smad3 NF-κB Signaling pathway
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信息技术推动乡村绿色发展的要求、实践及趋势 被引量:1
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作者 李周 《企业经济》 北大核心 2024年第5期5-14,F0002,共11页
信息成为数字、数据和产生价值是由信息技术的应用来实现的。我国乡村应用信息技术的硬体条件已经初步具备,应用信息技术的软体条件尚需作较大的改进。政府的主要职责是为乡村绿色发展和乡村生态系统保护应用信息技术提供更好的宏观政... 信息成为数字、数据和产生价值是由信息技术的应用来实现的。我国乡村应用信息技术的硬体条件已经初步具备,应用信息技术的软体条件尚需作较大的改进。政府的主要职责是为乡村绿色发展和乡村生态系统保护应用信息技术提供更好的宏观政策环境和更多的信息技术产品,使信息技术成为乡村振兴、农业绿色发展的推动力,成为规范各利益相关者行为的评价工具,让农民手中的智能手机在推动乡村绿色发展方面发挥更大的作用。乡村应用信息技术的重点要由协调政府与农民的关系拓展到协调农民和市场的关系。信息技术的突破和信息技术服务的创新,是一个不断有新起点,不断出新人才的领域,它是年轻科技人员,包括大学生、研究生施展才华,为推动中国乡村和农业绿色发展作贡献的重要平台。 展开更多
关键词 信息技术 乡村绿色发展 智能手机 环境信息 技术产品
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深海多金属结核集矿装置水力输送流场分析与试验
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作者 彭建平 李俊 +2 位作者 程阳锐 黎宙 吴冬华 《矿冶工程》 CAS 北大核心 2024年第2期1-4,共4页
对深海多金属结核集矿装置水力输送流场进行了理论计算,得到了多金属结核粒径与输送通道最小输送速度的关系;仿真分析了喷嘴射流速度分别为15、20、25 m/s时输送通道内水流流态分布,给出了流道下表面30 mm处的流速。在实验室进行了输送... 对深海多金属结核集矿装置水力输送流场进行了理论计算,得到了多金属结核粒径与输送通道最小输送速度的关系;仿真分析了喷嘴射流速度分别为15、20、25 m/s时输送通道内水流流态分布,给出了流道下表面30 mm处的流速。在实验室进行了输送喷嘴不同射流速度的采集试验,实验结果与理论计算及仿真分析结果相符。 展开更多
关键词 多金属结核 深海采矿 集矿装置 喷嘴射流 流体仿真 管道输送
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基于金属-介质-金属的可调谐窄带完美吸收的研究
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作者 王晓坤 李周 梁国龙 《中国光学(中英文)》 EI CAS CSCD 北大核心 2024年第2期263-270,共8页
为了实现窄带完美吸收,本文提出了一种简单的三层金-二氧化硅-金薄膜(MDM)结构。通过电磁波时域差分算法(FDTD)进行模拟仿真和理论计算,详细分析了该结构的可调谐吸收特性,同时建立了理论模型,分析了其中存在的电磁模式以及窄带完美吸... 为了实现窄带完美吸收,本文提出了一种简单的三层金-二氧化硅-金薄膜(MDM)结构。通过电磁波时域差分算法(FDTD)进行模拟仿真和理论计算,详细分析了该结构的可调谐吸收特性,同时建立了理论模型,分析了其中存在的电磁模式以及窄带完美吸收的物理机制。首先,利用电磁波时域差分算法和传输矩阵算法(TMM)对该结构进行了理论计算,详细地分析了各个结构参数对吸收光谱的影响。然后,对该结构形成的窄带完美吸收物理机制进行了分析讨论。最后,利用磁控溅射制备手段,成功制备了三层结构的样片。实验观测到的结果与理论仿真一致。实验结果表明:本文提出的窄带完美吸收结构,最窄带宽约为21 nm,最高吸收可达99.51%,基本实现了窄带完美吸收。本文研究成果为相关应用奠定了基础。 展开更多
关键词 薄膜 完美吸收 超薄薄膜
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基于改进Yolov5模型的纱筒余纱量检测方法
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作者 史伟民 李洲 +2 位作者 陆伟健 屠佳佳 徐寅哲 《纺织学报》 EI CAS CSCD 北大核心 2024年第7期196-203,共8页
为实现针织圆纬机纱架上纱筒余纱量的实时检测,提出一种深度学习与传统图像处理相结合的检测方法。通过优化Yolov5的主干网络并加入Shuffle-Attention注意力机制,利用改进后模型在图像中检测并框出纱筒位置;然后利用透视变换、均值偏移... 为实现针织圆纬机纱架上纱筒余纱量的实时检测,提出一种深度学习与传统图像处理相结合的检测方法。通过优化Yolov5的主干网络并加入Shuffle-Attention注意力机制,利用改进后模型在图像中检测并框出纱筒位置;然后利用透视变换、均值偏移、canny轮廓检测、闭操作等处理获取纱筒内外圆轮廓,设计基于梯度下降的圆拟合算法,拟合纱筒内外圆的轮廓,得到纱筒的内外圆半径;最后结合小孔成像的原理完成纱筒余纱量的测量。结果表明:改进后的Yolov5模型在纱筒检测精度上达到99.5%,检测速度可达20帧/s,同时模型参数减少至3.255×106可检测的最小纱筒余纱量为3 mm,当纱筒余纱量小于3 mm后,将其视为空筒,进行延时更换。本文算法拟合圆所花费时间是传统霍夫圆检测算法的1/4左右,因此可满足针织车间的实际应用需求。 展开更多
关键词 改进Yolov5模型 透视变换 均值偏移 梯度下降法 纱筒余纱量 针织圆纬机
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The dissolution of total suspended solids and treatment strategy of tailwater in a Litopenaeus vannamei recirculating aquaculture system
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作者 Yuhuan SUN Jian LU +3 位作者 Tianlong QIU li zhou Jianming SUN Yishuai DU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第3期1197-1205,共9页
In recirculating aquaculture systems(RASs),the effective treatment of aquaculture tailwater is essential to maintain the health of the RAS.This study investigated the optimal time and method for tailwater treatment du... In recirculating aquaculture systems(RASs),the effective treatment of aquaculture tailwater is essential to maintain the health of the RAS.This study investigated the optimal time and method for tailwater treatment during three periods of the aquaculture of the Litopenaeus vannamei:nursery(0–26 d),middle(27–57 d),and later(57–104 d).The variation of several water parameters during the dissolution of total suspended solid(TSS)in tailwater,applied with the effects of ozone on the microorganism and water quality parameters were investigated.Results showed that the TSS concentrations in tailwater decreased with time,although not significantly(P>0.05),whereas total ammonia nitrogen(TAN),nitrite(NO-2-N),and nitrate(NO_(3)^(-)-N)increased significantly(P<0.05).Therefore,TSS should be removed from the tailwater as early as possible,being most optimal within 4 h.Ozone removed 38.24%–48.95%of TSS,17.78%–90.14%of TAN,and 87.50%–98.90%of NO-2-N after 4 h of treatment.However,it resulted in the significant accumulation of NO_(3)^(-)-N.Moreover,the total number of Vibrio and bacterial counts in aquaculture tailwater was reduced completely by ozone within 4 h.Thus,these results provided technical details and data support for the effective treatment of tailwater from shrimp RAS. 展开更多
关键词 DISSOLUTION Litopenaeus vannamei OZONATION recirculating aquaculture system(RAS) tailwater treatment total suspended solid
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Rapid authentication of different herbal medicines by heating online extraction electrospray ionization mass spectrometry
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作者 Zidong Qiu Chaofa Wei +9 位作者 Xiang li Changjiangsheng Lai Zhilai Zhan Yan Jin li zhou Qingxiu Hao Jian Yang Shuanglong Wang liping Kang Luqi Huang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第3期296-304,共9页
The rapid and accurate authentication of traditional Chinese medicines(TCMs)has always been a key scientific and technical problem in the field of pharmaceutical analysis.Herein,a novel heating online extraction elect... The rapid and accurate authentication of traditional Chinese medicines(TCMs)has always been a key scientific and technical problem in the field of pharmaceutical analysis.Herein,a novel heating online extraction electrospray ionization mass spectrometry(H-oEESI-MS)was developed for the rapid and direct analysis of extremely complex substances without the requirement for any sample pretreatment or pre-separation steps.The overall molecular profile and fragment structure features of various herbal medicines could be completely captured within 10–15 s,with minimal sample(<0.5 mg)and solvent consumption(<20μL for one sample).Furthermore,a rapid differentiation and authentication strategy for TCMs based on H-oEESI-MS was proposed,including metabolic profile characterization,characteristic marker screening and identification,and multivariate statistical analysis model validation.In an analysis of 52 batches of seven types of Aconitum medicinal materials,20 and 21 key compounds were screened out as the characteristic markers of raw and processed Aconitum herbal medicines,respectively,and the possible structures of all the characteristic markers were comprehensively identified based on Compound Discoverer databases.Finally,multivariate statistical analysis showed that all the different types of herbal medicines were well differentiated and identified(R^(2)X>0.87,R^(2)Y>0.91,and Q^(2)>0.72),which further verified the feasibility and reliability of this comprehensive strategy for the rapid authentication of different TCMs based on H-oEESI-MS.In summary,this rapid authentication strategy realized the ultra-high-throughput,low-cost,and standardized detection of various complex TCMs for the first time,thereby demonstrating wide applicability and value for the development of quality standards for TCMs. 展开更多
关键词 Heating online extraction electrospray ionization mass spectrometry Rapid authentication Traditional Chinese medicine
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2D Nb_(2)CT_(x) MXene/MoS_(2) heterostructure construction for nonlinear optical absorption modulation
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作者 Yiduo Wang Yingwei Wang +10 位作者 Yulan Dong li zhou Jianlong Kang Ning Wang Yejun li Xiaoming Yuan Zhengwei Zhang Han Huang Mengqiu Long Si Xiao Jun He 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第10期6-16,共11页
Two-dimensional(2D)nonlinear optical mediums with high and tunable light modulation capability can significantly stimulate the development of ultrathin,compact,and integrated optoelectronics devices and photonic eleme... Two-dimensional(2D)nonlinear optical mediums with high and tunable light modulation capability can significantly stimulate the development of ultrathin,compact,and integrated optoelectronics devices and photonic elements.2D carbides and nitrides of transition metals(MXenes)are a new class of 2D materials with excellent intrinsic and strong light-matter interaction characteristics.However,the current understanding of their photo-physical properties and strategies for improving optical performance is insufficient.To address this issue,we rationally designed and in situ synthesized a 2D Nb_(2)C/MoS_(2) heterostructure that outperforms pristine Nb2C in both linear and nonlinear optical performance.Excellent agreement between experimental and theoretical results demonstrated that the Nb_(2)C/MoS_(2) inherited the preponderance of Nb_(2)C and MoS_(2) in absorption at different wavelengths,resulting in the broadband enhanced optical absorption characteristics.In addition to linear optical modulation,we also achieved stronger near infrared nonlinear optical modulation,with a nonlinear absorption coefficient of Nb_(2)C/MoS_(2) being more than two times that of the pristine Nb_(2)C.These results were supported by the band alinement model which was determined by the X-ray photoelectron spectroscopy(XPS)experiment and first-principal theory calculation.The presented facile synthesis approach and robust light modulation strategy pave the way for broadband optoelectronic devices and optical modulators. 展开更多
关键词 MXenes optical properties modulation in situ growth carriers transfer nonlinear optical absorption
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Protective effect and mechanism insight of purified Antarctic krill phospholipids against mice ulcerative colitis combined with bioinformatics
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作者 Rong Huang Jiaxu Yao +4 位作者 li zhou Xiang li Jinrui Zhu Yueqi Hu Jikai liu 《Natural Products and Bioprospecting》 CSCD 2023年第1期615-626,共12页
Antarctic krill oil is functional oil and has a complex phospholipids composition that poses difficulties in elucidating its effect mechanism on ulcerative colitis(UC).The mechanism of UC action was studied by bioinfo... Antarctic krill oil is functional oil and has a complex phospholipids composition that poses difficulties in elucidating its effect mechanism on ulcerative colitis(UC).The mechanism of UC action was studied by bioinformatics,and the therapeutic effect of Antarctic krill phospholipids(APL)on dextran sulfate sodium(DSS)-induced colitis mice was verified.GO functional enrichment analysis uncovered an enrichment of these genes in the regulation of cell-cell adhesion,membrane region,signaling receptor activator activity,and cytokine activity.Meanwhile,the KEGG results revealed the genes were enriched in the TNF signaling pathway,pathogenic Escherichia coli infection,inflammatory bowel disease and tight junction.Animal experiments showed that APL treatment alleviated the UC symptoms and reduced inflammatory damage.Meanwhile,the expressions of the tight junction(TJ)proteins,ZO-1 and occludin,were restored,and the levels of IL-6 and TNF-αwere reduced.Moreover,Firmicutes/Bacteroidetes ratio in the intestinal microbiota was regulated,and the contents of short-chain fatty acids metabolites were raised.These findings would provide an insight for the beneficial effects of APL and dietary therapy strategies for UC. 展开更多
关键词 Ulcerative colitis Krill phospholipids Bioinformatics analysis Tight junction protein Intestinal microbiota
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Langerhans cell histiocytosis misdiagnosed as thyroid malignancy: A case report
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作者 Jing-Jing Shi You Peng +2 位作者 Yu Zhang li zhou Gang Pan 《World Journal of Clinical Cases》 SCIE 2023年第5期1152-1157,共6页
BACKGROUND The incidence of Langerhans cell histiocytosis(LCH) is low, and involvement of the thyroid is even rarer, which results in high missed diagnosis or misdiagnosis rates.CASE SUMMARY We report a young woman wi... BACKGROUND The incidence of Langerhans cell histiocytosis(LCH) is low, and involvement of the thyroid is even rarer, which results in high missed diagnosis or misdiagnosis rates.CASE SUMMARY We report a young woman with a thyroid nodule. Thyroid malignancy was suggested by fine needle aspiration, but she was eventually diagnosed with multisystem LCH, thus avoiding thyroidectomy.CONCLUSION The clinical manifestations of LCH involving the thyroid are atypical, and the diagnosis depends on pathology. Surgery is the main method for treating primary thyroid LCH, while chemotherapy is the main treatment method for multisystem LCH. 展开更多
关键词 THYROID Langerhans cell histiocytosis THYROIDECTOMY TREATMENT Case report
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Correction:Protective effect and mechanism insight of purified Antarctic krill phospholipids against mice ulcerative colitis combined with bioinformatics
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作者 Rong Huang Jiaxu Yao +4 位作者 li zhou Xiang li Jinrui Zhu Yueqi Hu Jikai liu 《Natural Products and Bioprospecting》 CSCD 2023年第1期597-597,共1页
Correction:Natural Products and Bioprospecting(2023)13:11 https://doi.org/10.1007/s13659-023-00375-2 Following publication of the original article[1],the authors reported that“krill”was mistakenly written as“kill”... Correction:Natural Products and Bioprospecting(2023)13:11 https://doi.org/10.1007/s13659-023-00375-2 Following publication of the original article[1],the authors reported that“krill”was mistakenly written as“kill”in the title.The correct title should read:Protective effect and mechanism insight of purified Antarctic krill phospholipids against mice ulcerative coli-tis combined with bioinformatics The original article[1]has been updated. 展开更多
关键词 ANTARCTIC KRILL PROSPECTING
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Effects of Polygonatum odoratum Polysaccharides on the Quality of White Chili Peppers in Jars
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作者 Xiuqiang WANG li zhou +4 位作者 Chenzhong JIN Yihong HU Jing QIU Yunyun zhou Yan WANG 《Agricultural Biotechnology》 CAS 2023年第4期37-40,共4页
[Objectives]This study was conducted to investigate the effects of Polygonatum odoratum polysaccharides on the quality of white chili peppers in jars.[Methods]White chili peppers were pickled by adding different conce... [Objectives]This study was conducted to investigate the effects of Polygonatum odoratum polysaccharides on the quality of white chili peppers in jars.[Methods]White chili peppers were pickled by adding different concentrations of P.odoratum polysaccharides with traditional pickling technology,and its nitrite content,pH and sensory quality were analyzed and detected.[Results]The results showed that,compared with the control group without adding P.odoratum polysaccharides,the nitrite content in white chili peppers in jars decreased after adding P.odoratum polysaccharides.When the addition amount of P.odoratum polysaccharides was 0.002%,the inhibition rate of nitrite reached the maximum.Under the same fermentation time,P.odoratum polysaccharides could significantly reduce the pH value of pickles.When the addition amount of P.odoratum polysaccharide was 0.002%and the pickling time was 3 months,the sensory quality of white chili peppers in jars was the best.At this point,white chili peppers in jars had rich aroma and tasted soft and sour,and the sour and salinity were suitable.As the fermentation time continued to increase,the chili aroma of white chili peppers in jars gradually decreased,and the sour taste became more pronounced.[Conclusions]This study can provide reference for the safety and quality control of white chili peppers in jars. 展开更多
关键词 Polygonatum odoratum polysaccharides White chili peppers in jars Pickling process QUALITY
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1980-2020年贵州省草地空间分布格局演变及驱动力分析 被引量:1
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作者 余万洋 陈怡帆 +3 位作者 方发永 张金鑫 李舟 赵龙山 《草业学报》 CSCD 北大核心 2024年第1期1-18,共18页
草地在喀斯特地区石漠化治理和畜牧业发展中发挥重要作用,探明草地空间分布格局演变特征及其驱动力,对维护区域草地生态功能,实现可持续发展具有重要意义。本研究基于土地利用数据集,分析贵州省1980-2020年草地空间转移特征,将景观格局... 草地在喀斯特地区石漠化治理和畜牧业发展中发挥重要作用,探明草地空间分布格局演变特征及其驱动力,对维护区域草地生态功能,实现可持续发展具有重要意义。本研究基于土地利用数据集,分析贵州省1980-2020年草地空间转移特征,将景观格局与空间自相关相结合,深入识别草地空间分布格局演化规律及有效管理区域,并利用地理探测器量化草地空间分布格局演变的驱动力。结果表明:1)40年来,贵州省草地面积变化可划分为增长期(1980-2000年)、衰退期(2000-2015年)、恢复期(2015-2020年)3个阶段,草地面积总体上减少了176.88 km^(2)。发生变化区域集中在西部与南部地区,以草地和林地、耕地之间的转移为主,草地总体空间分布格局表现出“西部与南部高,东部与北部低”的特征;2)草地整体景观破碎程度增加,聚合度降低,形状趋于复杂,区县尺度的草地斑块更破碎和分散,但形状更规则;3)草地全局空间自相关程度减弱,局部自相关存在高-高聚集和低-高聚集的空间聚类现象,且集中分布在西部与南部地区;4)草地空间分布格局主要受自然因素的影响,海拔是主导因子,解释力最高,为42.9%。双因子的交互作用可增强对草地空间分布格局的解释力,海拔与牧业产值、年平均气温、人口密度、GDP均存在较强的交互作用,在海拔主导的草地总体分布格局下,区域间社会经济因素的不同和变化显著影响草地空间分布格局的演变,同时地区政策起重要导向作用。 展开更多
关键词 草地 空间分布动态 景观格局 空间自相关 驱动因素 贵州省
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Effect of Resistance Training,Aerobic Exercise Before Doula-Assisted Delivery on the Psychological Well-Being and Labor Duration of Parturients
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作者 Jing zhou Sha Tang +2 位作者 li zhou Cong Jiang Wenjian Fan 《Journal of Clinical and Nursing Research》 2023年第6期118-123,共6页
Objective:To investigate the impact of resistance training and aerobic exercise before doula-assisted delivery on the psychological well-being and labor duration of parturients.Methods:105 cases of parturients who gav... Objective:To investigate the impact of resistance training and aerobic exercise before doula-assisted delivery on the psychological well-being and labor duration of parturients.Methods:105 cases of parturients who gave birth in our hospital from February 2021 to April 2023 were included in this study.The patients were divided into a control group of 52 cases and an observation group of 53 cases.The patients in the control group received no particular intervention before delivery and only received doula assistance.The patients in the observation group received resistance training,aerobic exercise,and doula assistance prior to giving birth.After delivery,the mothers were observed for 2 hours in the delivery room and then returned to the maternal and infant ward.The observation indicators of the two groups were compared.Results:In comparison to the control group,the observation group exhibited shorter durations in the first,second,and third stages of labor,as well as the total delivery time.Additionally,the amount of postpartum blood loss at 2 hours was smaller in the observation group.The rate of cesarean section was lower,and the rate of vaginal natural delivery was higher in the observation group.Following the intervention,both groups of postpartum women showed decreased SAS and SDS scores compared to before the intervention.Moreover,the observation group had lower scores than the control group.These differences were all statistically significant(P<0.05).Conclusion:Resistance training and aerobic exercise before doula-assisted delivery can effectively improve the psychological state of parturients,shorten labor duration,increase the rate of natural vaginal delivery,and reduce pain and postpartum hemorrhage. 展开更多
关键词 Doula assistance Resistance training Aerobic exercise PARTURIENT Psychological state Labor duration
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超高压及热处理后不同果块竹笋软罐头质地差异的研究
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作者 陈丹 郑炯 +4 位作者 张甫生 董丽 胡小松 李周 胡祚 《食品与发酵工业》 CAS CSCD 北大核心 2024年第17期318-327,共10页
为了改善不同果块竹笋软罐头的质地及提高其食用品质,该文探究了超高压(ultra-high pressure,UHP)及热处理(thermal processing,TP)对半条状、丝状、片状及丁状等不同果块竹笋的硬度、汤汁黏度及pH、相对电导率、微观结构、纤维素及木... 为了改善不同果块竹笋软罐头的质地及提高其食用品质,该文探究了超高压(ultra-high pressure,UHP)及热处理(thermal processing,TP)对半条状、丝状、片状及丁状等不同果块竹笋的硬度、汤汁黏度及pH、相对电导率、微观结构、纤维素及木质素含量、果胶含量及酯化度等影响。结果表明,经UHP和TP后,与热烫对照相比,半条状、丝状、片状、丁状果块硬度分别下降了3.2%、8.6%、14.7%、23.5%和37.4%、46.2%、52.4%、64.8%;加工后罐头汤汁黏度及pH随着果块体积的减小而升高,TP汤汁黏度远高于UHP;微观结构显示UHP后细胞排列更为紧密,而TP后细胞间隙增大,且TP电导率远高于UHP,果块越小加工后细胞破损越严重、电导率越大;与TP相比,UHP竹笋有更高的螯合性果胶(chelator soluble pectin,CSP)和碱溶性果胶(sodium carbonate soluble pectin,NSP)以及更低的水溶性果胶(water soluble pectin,WSP),果块越小加工后其CSP、NSP越低,WSP越高;UHP果胶酯化度显著低于TP,但不同果块之间酯化度无显著差异;UHP/TP后不同果块纤维素及木质素含量未产生显著变化。综上,加工后不同果块竹笋的质地保持效果由高到低依次为:半条状>丝状>片状>丁状,且与TP相比,UHP能更好地保持竹笋质地。 展开更多
关键词 超高压 热处理 竹笋 果块大小 质地
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高阻型单相接地故障信号的暂态分量影响因素研究 被引量:1
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作者 李瑞祥 李舟 +5 位作者 李巍 王雨 王少鲁 黄易之 李永峰 杨兰均 《电力电容器与无功补偿》 2024年第2期100-106,116,共8页
高阻型单相接地故障信号的暂态分量,在故障过渡电阻这一主要影响因素之外,还受到以下影响因素的制约,进而影响暂态判据选线的准确度:配电网发生故障时所运用的系统接地方式、故障发生时的相角、故障发生点距母线的距离、故障发生出线的... 高阻型单相接地故障信号的暂态分量,在故障过渡电阻这一主要影响因素之外,还受到以下影响因素的制约,进而影响暂态判据选线的准确度:配电网发生故障时所运用的系统接地方式、故障发生时的相角、故障发生点距母线的距离、故障发生出线的长度等。其中系统接地方式由于为配电网系统本身的设计所导致,不受故障本身随机性的影响,因而其影响对于研究高阻型单相接地故障特征的暂态分量具有基础意义。本文利用了Matlab-Simulink仿真平台,重点针对过渡电阻阻值、中性点接地方式对高阻型单相接地故障暂态分量的影响进行了仿真分析,着重探究了过渡电阻阻值以及几种中性点非有效接地方式,在接近真实情况的三相不平衡条件下对高阻型单相接地故障暂态分量的影响。结果表明高阻型单相接地故障的过渡电阻较小、系统消弧线圈补偿度较小或中性点不接地,将影响高阻型单相接地故障信号的暂态分量并使得其强度较大、信噪比较高。 展开更多
关键词 高阻型单相接地故障 暂态分量 单相接地故障选线
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