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Long-term radiofrequency electromagnetic fields exposure attenuates cognitive dysfunction in 5×FAD mice by regulating microglial function
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作者 Yeonghoon Son Hye-Jin Park +3 位作者 Ye Ji Jeong Hyung-Do Choi Nam Kim Hae-June Lee 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第11期2497-2503,共7页
We have previously found that long-term effects of exposure to radiofrequency electromagnetic fields in 5xFAD mice with severe late-stage Alzheimer’s disease reduced both amyloid-βdeposition and glial activation,inc... We have previously found that long-term effects of exposure to radiofrequency electromagnetic fields in 5xFAD mice with severe late-stage Alzheimer’s disease reduced both amyloid-βdeposition and glial activation,including microglia.To examine whether this therapeutic effect is due to the regulation of activated microglia,we analyzed mic roglial gene expression profiles and the existence of microglia in the brain in this study.5xFAD mice at the age of 1.5 months were assigned to sham-and radiofrequency electromagnetic fields-exposed groups and then animals were exposed to 1950 MHz radiofrequency electromagnetic fields at a specific absorption rate of 5 W/kg for 2 hours/day and 5 days/week for 6 months.We conducted behavioral tests including the object recognition and Y-maze tests and molecular and histopathological analysis of amyloid precursor protein/a myloid-beta metabolism in brain tissue.We confirmed that radiofrequency electromagnetic field exposure for 6 months ameliorated cognitive impairment and amyloid-βdeposition.The expression levels of Iba1(pan-microglial marker)and colony-stimulating factor 1 receptor(CSF1R;regulates microglial prolife ration)in the hippocampus in 5xFAD mice treated with radiofrequency electromagnetic fields were significantly reduced compared with those of the sham-exposed group.Subsequently,we analyzed the expression levels of genes related to mic rogliosis and microglial function in the radiofrequency electromagnetic fields-exposed group compared to those of a CSF1R inhibitor(PLX3397)-treated group.Both radiofrequency electromagnetic fields and PLX3397 suppressed the levels of genes related to microgliosis(Csf1r,CD68,and Ccl6)and pro-inflammatory cytokine interleukin-1β.N otably,the expression levels of genes related to mic roglial function,including Trem2,Fcgr1α,Ctss,and Spi1,were decreased after long-term radiofrequency electromagnetic field exposure,which was also observed in response to microglial suppression by PLX3397.These results showed that radiofrequency electromagnetic fields ameliorated amyloid-βpathology and cognitive impairment by suppressing amyloid-βdeposition-induced microgliosis and their key regulator,CSF1R. 展开更多
关键词 5×FAD Alzheimer’s disease CsF1R long term exposure microglial function NEUROINFLAMMATION radiofrequency electromagnetic fields therapeutic effect
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基于BiLSTM-Attention的F_(10.7)指数预测模型与中国自主数据集的应用
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作者 闫帅楠 李雪宝 +7 位作者 董亮 黄文耿 王晶 闫鹏朝 娄恒瑞 黄徐胜 李哲 郑艳芳 《空间科学学报》 CAS CSCD 北大核心 2024年第2期251-261,共11页
F_(10.7)指数是太阳活动的重要指标,准确预测F_(10.7)指数有助于预防和缓解太阳活动对无线电通信、导航和卫星通信等领域的影响.基于F_(10.7)射电流量的特性,在双向长短时记忆网络(Bidirectional Long Short-Term Memory Network,BiLSTM... F_(10.7)指数是太阳活动的重要指标,准确预测F_(10.7)指数有助于预防和缓解太阳活动对无线电通信、导航和卫星通信等领域的影响.基于F_(10.7)射电流量的特性,在双向长短时记忆网络(Bidirectional Long Short-Term Memory Network,BiLSTM)基础上融入注意力机制(Attention),提出了一种基于BiLSTM-Attention的F_(10.7)预报模型.在加拿大DRAO数据集上其平均绝对误差(MAE)为5.38,平均绝对百分比误差(MAPE)控制在5%以内,相关系数(R)高达0.987,与其他RNN模型相比拥有优越的预测性能.针对中国廊坊L&S望远镜观测的F_(10.7)数据集,提出了一种转换平均校准(Conversion Average Calibration,CAC)方法进行数据预处理,处理后的数据与DRAO数据集具有较高的相关性.基于该数据集对比分析了RNN系列模型的预报效果,实验结果表明,BiLSTM-Attention和BiLSTM两种模型在预测F_(10.7)指数方面具有较好的优势,表现出较好的预测性能和稳定性. 展开更多
关键词 F_(10.7)预报 双向长短时记忆网络 注意力机制 L&s数据集
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基于潮汐附加构造应力的2013年灯塔M_(S)5.1地震射出长波辐射变化分析
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作者 荆涛 Boonphor Phetphouthongdy +4 位作者 Chansouk Sioudom 刘洋洋 李继庚 康春丽 马未宇 《地震》 CSCD 北大核心 2024年第2期52-62,共11页
针对2013年1月23日辽宁灯塔M_(S)5.1地震,利用引潮力附加构造应力(Additional Tectonic Stress Caused By Tidal Force,ATSCTF)计算模型,计算得到震中位置(41.5°N,123.2°E)在地震前5周以及震后3周(2012年12月16日—2013年2月1... 针对2013年1月23日辽宁灯塔M_(S)5.1地震,利用引潮力附加构造应力(Additional Tectonic Stress Caused By Tidal Force,ATSCTF)计算模型,计算得到震中位置(41.5°N,123.2°E)在地震前5周以及震后3周(2012年12月16日—2013年2月15日)的ATSCTF变化。地震发生时,ATSCTF垂直方向分量处于高相位点附近,显示引潮力对本次正断层走滑型地震具有诱发作用。以ATSCTF变化周期的各低相位点时间(2012年12月19日、2013年1月4日、2013年1月18日、2013年2月2日)数据分别为背景,各周期期后数据分别与背景逐日相减,计算研究区(36°N~46°N,118°E~128°E)范围内,National Oceanic and Atmospheric Administration(NOAA)卫星射出长波辐射数据(Outgoing Long Wave Radiation,OLR)在各ATSCTF周期时段分布及其变化。结果显示,无震的ATSCTF变化的A、B、D周期,震中附近OLR无变化;发震的ATSCTF变化的C周期,在空间上,该地区震前OLR仅震中及其南侧区域发生了显著连续升高变化过程,在时间上经历了初始微异常→异常加强→高峰→衰减→发震→平静的演化过程,与岩石应力加载—破裂经历:初始微动破裂→扩张破裂→应力闭锁→地震爆发→平静的力学演化过程中各阶段红外辐射特征一致;显示引潮力对处于临界状态的活动断层具有诱发作用,而OLR是地震构造应力应变过程辐射表征。 展开更多
关键词 2013年灯塔M_(s)5.1地震 长波辐射 潮汐附加构造应力 震前ATsCTF周期异常
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基于深度学习和广义S变换协同的风速预测
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作者 朱哲萱 马汝为 +1 位作者 曹黎媛 李春祥 《太阳能学报》 EI CAS CSCD 北大核心 2024年第7期664-671,共8页
针对实测风速的非平稳性特点,提出一种基于深度学习和时频分析的风速混合预测方法。首先,采用经验模态分解(EMD)将风速分解为若干子层,由此得到趋势分量和脉动分量以降低风速的非线性。根据2个分量的时频特性,采用长短时记忆(LSTM)处理... 针对实测风速的非平稳性特点,提出一种基于深度学习和时频分析的风速混合预测方法。首先,采用经验模态分解(EMD)将风速分解为若干子层,由此得到趋势分量和脉动分量以降低风速的非线性。根据2个分量的时频特性,采用长短时记忆(LSTM)处理趋势分量,极限学习机(ELM)处理脉动分量。其次,引入广义S变换(GST)来获得预测过程中的时频特性。同时,采用改进的灰狼算法(IGWO)对GST、LSTM和ELM的参数进行优化。最后,以内蒙古某风场实测风速对所提模型进行验证,结果表明该模型具有较高的精度。 展开更多
关键词 风电场 风速 预测 长短时记忆 极限学习机 广义s变换
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基于三次S型速度控制算法的移动机械臂末端振动研究
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作者 刘益军 李正强 +1 位作者 赖建防 吕伟宏 《机械制造与自动化》 2024年第1期232-237,共6页
移动机械臂在实际工作环境中,受其自身柔性特征和外部因素的影响而引起机械臂末端的振动,而速度控制是实现机械臂末端抑振的有效手段之一。以UR10机械臂和Husky移动平台组成的移动机械臂为研究对象,针对梯形和S型速度控制算法的不足,提... 移动机械臂在实际工作环境中,受其自身柔性特征和外部因素的影响而引起机械臂末端的振动,而速度控制是实现机械臂末端抑振的有效手段之一。以UR10机械臂和Husky移动平台组成的移动机械臂为研究对象,针对梯形和S型速度控制算法的不足,提出一种三次S型速度控制算法,通过建立移动机械臂刚柔耦合动力学的理论和仿真模型得到移动机械臂末端的振动位移曲线和加速度变化曲线,验证了三次S型速度控制算法的正确性和抑振效果的有效性。 展开更多
关键词 移动机械臂 刚柔耦合 三次s型速度控制算法
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The Significance of Family in Long Day's Journey Into Night
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作者 康晓亚 《中国校外教育》 2011年第12期75-75,共1页
Long Day's Journey Into Night is considered one of the best drama Eugene O'Neill has ever written. It was published and staged posthumously as per the will of the playwright and won him a fourth Pulitzer Prize... Long Day's Journey Into Night is considered one of the best drama Eugene O'Neill has ever written. It was published and staged posthumously as per the will of the playwright and won him a fourth Pulitzer Prize. This paper tries to analyze this tragedy from conventional perspective of tragedies and concludes that the Tyrone family in the play serves as the protagonist and the play conforms to traditional structure of a tragedy,though no deaths and the like are found in the end. 展开更多
关键词 英语教学 教学方法 英语翻译 英语阅读
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Plasma long noncoding RNA expression profile identified by microarray in patients with Crohn's disease 被引量:5
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作者 Dong Chen Jiang Liu +3 位作者 Hui-Ying Zhao Yi-Peng Chen Zun Xiang Xi Jin 《World Journal of Gastroenterology》 SCIE CAS 2016年第19期4716-4731,共16页
AIM: To investigate the expression pattern of plasma long noncoding RNAs(lnc RNAs) in Chrohn's disease(CD) patients.METHODS: Microarray screening and q RT-PCR verification of lnc RNAs and m RNAs were performed in ... AIM: To investigate the expression pattern of plasma long noncoding RNAs(lnc RNAs) in Chrohn's disease(CD) patients.METHODS: Microarray screening and q RT-PCR verification of lnc RNAs and m RNAs were performed in CD and control subjects, followed by hierarchy c l u s t e r i n g, G O a n d K E G G p a t h w a y a n a l y s e s. Significantly dysregulated lnc RNAs were categorized into subgroups of antisense lnc RNAs, enhancer lnc RNAs and linc RNAs. To predict the regulatory effect of lnc RNAs on m RNAs, a CNC network analysis was performed and cross linked with significantly changed lnc RNAs. The overlapping lnc RNAs were randomly selected and verified by q RT-PCR in a larger cohort. RESULTS: Initially, there were 1211 up-regulated and 777 down-regulated lnc RNAs as well as 1020 up-regulated and 953 down-regulated m RNAs after microarray analysis; a heat map based on these results showed good categorization into the CD and control groups. GUSBP2 and AF113016 had the highest fold change of the up- and down-regulated lnc RNAs, whereas TBC1D17 and CCL3L3 had the highest foldchange of the up- and down-regulated m RNAs. Six(SNX1, CYFIP2, CD6, CMTM8, STAT4 and IGFBP7) of 10 m RNAs and 8(NR_033913, NR_038218, NR_036512, NR_049759, NR_033951, NR_045408, NR_038377 and NR_039976) of 14 lnc RNAs showed the same change trends on the microarray and q RT-PCR results with statistical significance. Based on the q RT-PCR verified m RNAs, 1358 potential lnc RNAs with 2697 positive correlations and 2287 negative correlations were predicted by the CNC network. CONCLUSION: The plasma lnc RNAs profiles provide preliminary data for the non-invasive diagnosis of CD and a resource for further specific lnc RNA-m RNA pathway exploration. 展开更多
关键词 Crohn’s DIsEAsE long noncoding RNA INFLAMMATORY BOWEL DIsEAsE PLAsMA MICROARRAY
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Isolation and Identification of a Specific cDNA Mapping to the Bam HI-I2 and -LFragments within the Inverted Repeats ofUnique Long Re-gion (IRL) in the Genom e ofMarek′s Disease Herpesvirus (MDV) Oncogenic Strain Beijing-1 被引量:13
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作者 Lu Chun, Wu Jianping, Zhang Xunhai, et al. Lu Chun, Wu Jianping, Zhang Xunhai, et al. Department of Microbiology and Immunology, Nanjing Medical University, Nanjing\ 210029 Acta Universitatis Medicinalis Nanjing, 19(6):447 《The Journal of Biomedical Research》 CAS 1999年第2期73-73,共1页
Objective\ To understand the transcription of BamHI L DNA fragment from genome of strong virulent GA strain of Marek′s disease herpesvirus (MDV) in lymphoblastoid tumor tissue induced by oncogenic strain Beijing 1 ... Objective\ To understand the transcription of BamHI L DNA fragment from genome of strong virulent GA strain of Marek′s disease herpesvirus (MDV) in lymphoblastoid tumor tissue induced by oncogenic strain Beijing 1 (a specific local strain in China) of MDV. Methods\ Two oligonucleotide primers were synthesized according to the reported sequence of \%meq\% gene an ideal oncogenic candidate and our previously determined sequence of BamHI L fragment of Marek′s disease herpesvirus (MDV), respectively. Reverse transcriptase PCR(RT PCR) assay was performed by using these primers and the mRNA as a template which was isolated from visceral lymphoblastoid tumors obtained from chickens artificially infected with strain Beijing 1 of oncogenic MDV. Southern blot molecular hybridization was further carried out to detect the product of RT PCR with digoxigenin labeled nucleotide probe from BamHI I2 and L fragment in the gene library of MDV strain GA, respectively. Results\ Two probes could simultaneously hybridize this cDNA amplified by RT PCR with a length of about 730 bp. Conclusion\ It is suggested that \%meq\% transcription could extend from the right hand end of BamHI I2 to the adjacent BamHI L, and the BamHI L region was likely to be transcribed in MDV induced lymphoblastoid tumors. 展开更多
关键词 CDNA IRL in the Genom e ofMarek Isolation and Identification of a specific cDNA Mapping to the Bam HI-I2 and LFragments within the Inverted Repeats ofUnique long Re-gion Oncogenic strain Beijing-1 s Disease Herpesvirus long RE MDV
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Luminescence Characterization of Mg Doped Y_2O_2S:Ti Long Afterglow Phosphor 被引量:3
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作者 张朋越 洪樟连 +2 位作者 沈华翔 徐珍秀 樊先平 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第z2期115-118,共4页
Y1.94-xMgxO2S:0.06Ti (0≤x≤0.10) phosphors with long afterglow were synthesized by solid state reaction route. The photoluminescence spectra, decay curves, thermoluminescent spectra and chromaticity coordinate curves... Y1.94-xMgxO2S:0.06Ti (0≤x≤0.10) phosphors with long afterglow were synthesized by solid state reaction route. The photoluminescence spectra, decay curves, thermoluminescent spectra and chromaticity coordinate curves were investigated. The results show that the luminescence intensity of Y1.94-xMgxO2S :0.06Ti (0≤x≤0. 10) phosphors decrease gradually with increasing Mg2+ ion content, and the shape of luminescence spectra and chromaticity coordinate change as well. Furthermore, two thermoluminescent peaks in single Ti-doped Y2O2S sample are found at 91.8 and 221.5℃, respectively. Nevertheless, significant different spectra were found for the Mg, Ti co-doped Y2O2S samples that three thermoluminescence peaks appear at 52.3, 141.7 and 226.8℃, respectively. These results indicate that the co-doped Mg ion changes the inherent trap depth of single Ti-doped Y2O2S: Ti phosphor, and induces simultaneously a new trap level in the Y1.94-xMgxO2S:0.06Ti phosphor. Based on the analysis of thermoluminescent spectra, photolumi-nescent spectra, decay curve and crystal structure defect, it was proposed that the varied structure defect and introduced new trap level by the doped Mg2+ ions should be responsible for reducing luminescence intensity and varying color in the Y1.94-x Mgx O2S : 0.06Ti phosphor. 展开更多
关键词 Y2O2s PHOsPHOR solid state reaction LUMINEsCENCE long afterglow rare earths
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Florid reactive periostitis ossificans of the humerus: Case report and differential diagnosis of periosteal lesions of long bones 被引量:4
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作者 Abha Soni Alec Weil +2 位作者 Shi Wei Kenneth A Jaffe Gene P Siegal 《World Journal of Orthopedics》 2015年第7期559-563,共5页
A case of florid reactive periostitis ossificans(RPO) arising in a long bone is presented. This is a rare bone proliferation with a pronounced periosteal reaction. Less than 100 cases have been described in the litera... A case of florid reactive periostitis ossificans(RPO) arising in a long bone is presented. This is a rare bone proliferation with a pronounced periosteal reaction. Less than 100 cases have been described in the literature with far fewer outside the bones of the hand, feet, fingers, and toes. Although the etiology is unknown, a relationship to preceding trauma is suggested. The imaging and histologic features show an overlap with other bone lesions including bizarre parosteal osteochondromatous proliferation, subungual exostosis, and malignant surface tumors of bone and cartilage which include, periosteal and parosteal osteosarcoma. It is important to recognize the clinical presentation and diagnostic features of RPO as a benign entity so that it is not mistaken for a more aggressive neoplasm. We present a case of a right distal humeral lesion that on histopathological review revealed florid RPO. This diagnosis was not suspected on imaging studies, but was made on open biopsy of the mass. The patient remains disease free, years postoperatively. In addition to presenting this unique case report, we review the pertinent literature, and offer a differential diagnosis and treatment strategy for its management. 展开更多
关键词 Bizarre parosteal osteochondromatous proliferation(Nora’s lesion) REACTIVE tumor-like LEsIONs of long bones FLORID REACTIVE PERIOsTITIs ossificans PERIOsTEAL and parosteal osteosarcomas
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S100 calcium binding protein A6 and associated long noncoding ribonucleic acids as biomarkers in the diagnosis and staging of primary biliary cholangitis 被引量:2
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作者 Xi-Hua Dong Di Dai +3 位作者 Zhi-Dong Yang Xiao-Ou Yu Hua Li Hui Kang 《World Journal of Gastroenterology》 SCIE CAS 2021年第17期1973-1992,共20页
BACKGROUND Primary biliary cholangitis(PBC)is a chronic and slowly progressing cholestatic disease,which causes damage to the small intrahepatic bile duct by immunoregulation,and may lead to cholestasis,liver fibrosis... BACKGROUND Primary biliary cholangitis(PBC)is a chronic and slowly progressing cholestatic disease,which causes damage to the small intrahepatic bile duct by immunoregulation,and may lead to cholestasis,liver fibrosis,cirrhosis and,eventually,liver failure.AIM To explore the potential diagnosis and staging value of plasma S100 calcium binding protein A6(S100A6)messenger ribonucleic acid(mRNA),LINC00312,LINC00472,and LINC01257 in primary biliary cholangitis.METHODS A total of 145 PBC patients and 110 healthy controls(HCs)were enrolled.Among them,80 PBC patients and 60 HCs were used as the training set,and 65 PBC patients and 50 HCs were used as the validation set.The relative expression levels of plasma S100A6 mRNA,long noncoding ribonucleic acids LINC00312,LINC00472 and LINC01257 were analyzed using quantitative reverse transcription-polymerase chain reaction.The bile duct ligation(BDL)mouse model was used to simulate PBC.Then double immunofluorescence was conducted to verify the overexpression of S100A6 protein in intrahepatic bile duct cells of BDL mice.Human intrahepatic biliary epithelial cells were treated with glycochenodeoxycholate to simulate the cholestatic environment of intrahepatic biliary epithelial cells in PBC.RESULTS The expression of S100A6 protein in intrahepatic bile duct cells was up-regulated in the BDL mouse model compared with sham mice.The relative expression levels of plasma S100A6 mRNA,log10 LINC00472 and LINC01257 were upregulated while LINC00312 was down-regulated in plasma of PBC patients compared with HCs(3.01±1.04 vs 2.09±0.87,P<0.0001;2.46±1.03 vs 1.77±0.84,P<0.0001;3.49±1.64 vs 2.37±0.96,P<0.0001;1.70±0.33 vs 2.07±0.53,P<0.0001,respectively).The relative expression levels of S100A6 mRNA,LINC00472 and LINC01257 were up-regulated and LINC00312 was down-regulated in human intrahepatic biliary epithelial cells treated with glycochenodeoxycholate compared with control(2.97±0.43 vs 1.09±0.08,P=0.0018;2.70±0.26 vs 1.10±0.10,P=0.0006;2.23±0.21 vs 1.10±0.10,P=0.0011;1.20±0.04 vs 3.03±0.15,P<0.0001,respectively).The mean expression of S100A6 in the advanced stage(III and IV)of PBC was up-regulated compared to that in HCs and the early stage(II)(3.38±0.71 vs 2.09±0.87,P<0.0001;3.38±0.71 vs 2.57±1.21,P=0.0003,respectively);and in the early stage(II),it was higher than that in HCs(2.57±1.21 vs 2.09±0.87,P=0.03).The mean expression of LINC00312 in the advanced stage was lower than that in the early stage and HCs(1.39±0.29 vs 1.56±0.33,P=0.01;1.39±0.29 vs 2.07±0.53,P<0.0001,respectively);in addition,the mean expression of LINC00312 in the early stage was lower than that in HCs(1.56±0.33 vs 2.07±0.53,P<0.0001).The mean expression of log10 LINC00472 in the advanced stage was higher than those in the early stage and HCs(2.99±0.87 vs 1.81±0.83,P<0.0001;2.99±0.87 vs 1.77±0.84,P<0.0001,respectively).The mean expression of LINC01257 in both the early stage and advanced stage were up-regulated compared with HCs(3.88±1.55 vs 2.37±0.96,P<0.0001;3.57±1.79 vs 2.37±0.96,P<0.0001,respectively).The areas under the curves(AUC)for S100A6,LINC00312,log10 LINC00472 and LINC01257 in PBC diagnosis were 0.759,0.7292,0.6942 and 0.7158,respectively.Furthermore,the AUC for these four genes in PBC staging were 0.666,0.661,0.839 and 0.5549,respectively.The expression levels of S100A6 mRNA,log10 LINC00472,and LINC01257 in plasma of PBC patients were decreased(2.35±1.02 vs 3.06±1.04,P=0.0018;1.99±0.83 vs 2.33±0.96,P=0.036;2.84±0.92 vs 3.69±1.54,P=0.0006),and the expression level of LINC00312 was increased(1.95±0.35 vs 1.73±0.32,P=0.0007)after treatment compared with before treatment using the paired t-test.Relative expression of S100A6 mRNA was positively correlated with log10 LINC00472(r=0.683,P<0.0001);serum level of collagen type IV was positively correlated with the relative expression of log10 LINC00472(r=0.482,P<0.0001);relative expression of S100A6 mRNA was positively correlated with the serum level of collagen type IV(r=0.732,P<0.0001).The AUC for the four biomarkers obtained in the validation set were close to the training set.CONCLUSION These four genes may potentially act as novel biomarkers for the diagnosis of PBC.Moreover,LINC00472 acts as a potential biomarker for staging in PBC. 展开更多
关键词 s100 calcium binding protein A6 long noncoding ribonucleic acids Primary biliary cholangitis Biomarker Diagnosis sTAGING
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Manipulation of spermatogonial stem cells in livestock species 被引量:7
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作者 Filipp Savvulidi Martin Ptacek +1 位作者 Karina Savvulidi Vargova Ludek Stadnik 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2019年第4期833-850,共18页
We are entering an exciting epoch in livestock biotechnology during which the fundamental approaches(such as transgenesis, spermatozoa cryopreservation and artificial insemination) will be enhanced based on the modern... We are entering an exciting epoch in livestock biotechnology during which the fundamental approaches(such as transgenesis, spermatozoa cryopreservation and artificial insemination) will be enhanced based on the modern understanding of the biology of spermatogonial stem cells(SSCs) combined with the outstanding recent advances in genomic editing technologies and in vitro cell culture systems. The general aim of this review is to outline comprehensively the promising applications of SSC manipulation that could in the nearest future find practical application in livestock breeding. Here, we will focus on 1) the basics of mammalian SSC biology;2) the approaches for SSC isolation and purification;3) the available in vitro systems for the stable expansion of isolated SSCs;4) a discussion of how the manipulation of SSCs can accelerate livestock transgenesis;5) a thorough overview of the techniques of SSC transplantation in livestock species(including the preparation of recipients for SSC transplantation,the ultrasonographic-guided SSC transplantation technique in large farm animals, and the perspectives to improve further the SSC transplantation efficiency), and finally, 6) why SSC transplantation is valuable to extend the techniques of spermatozoa cryopreservation and/or artificial insemination. For situations where no reliable data have yet been obtained for a particular livestock species, we will rely on the data obtained from studies conducted in rodents because the knowledge gained from rodent research is translatable to livestock species to a great extent. On the other hand, we will draw special attention to situations where such translation is not possible. 展开更多
关键词 CRIsPR/Cas9 Genome editing LIVEsTOCK TRANsGENEsIs long-term culture systems Male GERMLINE sTEM cells Recipient preparation sertoli CELLs spermatogonial sTEM CELLs Ultrasonographic-guided CANNULATION
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Optimization Algorithm for Operation Comfortability of Master Manipulator of Minimally Invasive Surgery Robot 被引量:2
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作者 李进华 王雪生 +3 位作者 邢元 王树新 李建民 梁科 《Transactions of Tianjin University》 EI CAS 2016年第2期95-104,共10页
To evaluate the operation comfortability in the master-slave robotic minimally invasive surgery(MIS), an optimal function was built with two operation comfortability decided indices, i.e., the center distance and volu... To evaluate the operation comfortability in the master-slave robotic minimally invasive surgery(MIS), an optimal function was built with two operation comfortability decided indices, i.e., the center distance and volume contact ratio. Two verifying experiments on Phantom Desktop and Micro Hand S were conducted. Experimental results show that the operation effect at the optimal relative location is better than that at the random location, which means that the optimal function constructed in this paper is effective in optimizing the operation comfortability. 展开更多
关键词 手术机器人 优化算法 舒适性 操作手 微创外科 验证实验 相对位置 微创手术
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An Analysis of Michael Long’s Interaction Hypothesis in Second Language Acquisition 被引量:5
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作者 单映 《科技信息》 2009年第29期227-229,共3页
The Interaction Hypothesis,which was first advanced by Michael Long,is considered as a further supplement or extension of the Input Hypothesis in the field of second language acquisition. This paper explains the main ... The Interaction Hypothesis,which was first advanced by Michael Long,is considered as a further supplement or extension of the Input Hypothesis in the field of second language acquisition. This paper explains the main claims of Michael Long's Interaction Hypothesis,the three steps to study how input and interaction affect the acquisition of a second language,and the importance of the interactional modifications applied by both participants of the interaction. Emphasis is placed on the evaluation of the theory as well as its relation to second language teaching,with many researchers' findings and arguments discussed as supporting evidence. It aims to help the effective application of this theory in second language teaching. 展开更多
关键词 第二语言 语法 学习方法 教学方法
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一种基于LSTM的汽车路噪预测方法 被引量:1
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作者 刘伟 黄海波 +2 位作者 范大力 王大一 丁渭平 《噪声与振动控制》 CSCD 北大核心 2023年第3期145-152,共8页
汽车路噪的分析与治理是NVH(Noise,Vibration And Harshness)工作的重要组成部分。由于路噪的产生机理复杂,建立机理模型较困难,故引入数据驱动方法对路噪进行研究。首先,对路噪影响因素进行剖析,界定出具有显著性的影响因素。在此基础... 汽车路噪的分析与治理是NVH(Noise,Vibration And Harshness)工作的重要组成部分。由于路噪的产生机理复杂,建立机理模型较困难,故引入数据驱动方法对路噪进行研究。首先,对路噪影响因素进行剖析,界定出具有显著性的影响因素。在此基础上,运用长短时记忆神经网络算法(LSTM)揭示路噪与其影响因素间的复杂非线性关系,建立路噪预测模型。进而在粗糙沥青路面分别以40 km/h、60 km/h的车速工况采集悬架相关部件振动数据和驾驶员右耳畔噪声数据,以获得样本用于路噪模型的训练和检验。并采用Mixup数据增强策略合成新的样本,从而使样本量不足状况得到改善。进一步,对LSTM路噪预测模型进行检验与分析,测试结果均方误差为0.076 2,表明预测效果良好,证明所提方法的有效性。同时,将BPNN、SVR与LSTM预测方法进行比较,发现LSTM路噪预测模型精度更高,泛化能力更好,从而证明该方法的优越性。 展开更多
关键词 声学 汽车路噪 路噪预测 LsTM 数据增强
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Analysis of the Contradictory Relationship among Family Members in Long Day' s Journey into Night 被引量:1
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作者 刘坤娜 王娟 《海外英语》 2012年第10X期195-196,共2页
Long Day' s Journey into Night is one of Eugene O' Neill' s (1888-1953) masterpieces, who is a great American playwright and called the father of modern American drama. This thesis aims at the analysis of ... Long Day' s Journey into Night is one of Eugene O' Neill' s (1888-1953) masterpieces, who is a great American playwright and called the father of modern American drama. This thesis aims at the analysis of the contradictions in family members in the play. The first part analyzes the contradictions between wife and husband. The second part focuses on the contradictory relationship in parents and sons. The contradictions between brothers are discussed in the third part. Through the study of the causes of the contradictory relationship among family members, the tragedy of the characters in the play will be explored to the readers, which is also the tragedy of modern Ameri can people. 展开更多
关键词 long Day’ s JOURNEY into NIGHT contradiction WIFE
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Kineto-static analysis of a novel high-speed parallel manipulator with rigid-flexible coupled links 被引量:2
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作者 孙涛 宋轶民 阎凯 《Journal of Central South University》 SCIE EI CAS 2011年第3期593-599,共7页
A novel high-speed parallel kinematic machine (PKM) named Delta-S parallel manipulator is proposed,which consists of a fixed base connected to a moving platform through three limbs with identical topology.Each limb is... A novel high-speed parallel kinematic machine (PKM) named Delta-S parallel manipulator is proposed,which consists of a fixed base connected to a moving platform through three limbs with identical topology.Each limb is composed of one driving arm and one follower arm,herein,the latter includes two strings and one middle rod,all located in a same plane.Compared with similar manipulators with uniform parameters,the novel and unique topology as well as the addition of two strings of Delta-S manipulator can remove the clearance of the spherical joints,reduce the inertial load of components further,improve the positioning accuracy and dynamic performance,and so on.In order to formulate the kineto-static model of Delta-S manipulator,the kineto-static analyses and models of the driving arm,the generalized follower and the moving platform can be carried out by the D'ALEMBERT principle.For the sake of obtaining the force analytic results of strings,the deformation compatibility condition of strings and the middle rod are determined.Furthermore,in virtue of the assumption of small deformation and the linear superposition principle,theminimal pre-tightening force of the strings is calculated.The main results include that the loads of the strings and the middle rod must be larger than "zero" and the pre-tightening force over the workspace must be larger than theminimal pre-tightening force at any time within the workspace,which lay the foundation for the dynamic analysis and the prototype manufacture of the Delta-S manipulator. 展开更多
关键词 并联机器人 静态分析 刚柔耦合 链接 达朗贝尔原理 线性迭加原理 拓扑结构 移动平台
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Temperature Dependence of Red Long Afterglow from Y_2O_2S∶Eu, Ti, Mg
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作者 Zhou Dongfang Shi Chaoshu +4 位作者 Qi Zeming Liu Miao Tao Ye Liu Bo Chen Yonghu 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第1期24-24,共1页
At low temperature, some long-lasting phosphors could not work well in practical applications. So it is necessary to investigate the temperature dependence of the phosphors. The Y2O2S.Eu, Ti, Mg microcrystalline sampl... At low temperature, some long-lasting phosphors could not work well in practical applications. So it is necessary to investigate the temperature dependence of the phosphors. The Y2O2S.Eu, Ti, Mg microcrystalline samples were prepared by solid state reaction method. Phosphors were sintered at 1150 ℃ for 20 min in air, putting in and taking out both at high temperature. The emission spectra and the afterglow spectra as well as the thermoluminescence curve were measured for Y2O2S:Eu, 展开更多
关键词 long after glow Y2O2s:Eu Ti Mg rare earths
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Striving to Gain a Long-term Stability for the China——U.S.Relationship
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作者 Tao Wenzhao 《和平与发展》 CSSCI 北大核心 2006年第3期57-64,共8页
关键词 U.s.Relationship striving to Gain a long-term stability for the China THAN long
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A gieat Weakthiough in 1996,guang Long's impoits and expoils amounted to over $110 blillion
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作者 Fu Lin 《大经贸》 北大核心 1997年第1期96-96,共1页
1996,It was the first year of implementing China’s ninth"Five Year Plan".In that year,China’s foreigneconomy & trade policy had been greatly read-justed. Despite so many difficulties and new challenges... 1996,It was the first year of implementing China’s ninth"Five Year Plan".In that year,China’s foreigneconomy & trade policy had been greatly read-justed. Despite so many difficulties and new challenges,GuangDong had taken a series of powerful measures on utilizingforeign capital and encouraging imports and exports.Export tradehad continuously increased, reform of enterprises had a greaterbreakthrough,The foreign capitals actually utilized had maintaineda good momentum of development.Looking back upon the passed year,the total annual importand export value of GuangDong had reached USD 110.04 bil-lion.of which the export amounted to USD 59.34 billion,whichis 37.9 percent of total annual Imp.& Exp.Value of the Country.Imports amounted $ 50.7 billion,foreign capital actually usedreached USD 13.9 billion, they were respectively up 5.8 percent,6.8 percent and 14 percent from the previous year.GuangDong’simports and exports emphasized efficient growth.It had 展开更多
关键词 blillion 110 A gieat Weakthiough in 1996 guang longs impoits and expoils amounted to over long
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