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A Novel Wideband Antenna for High Precision Surveying

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A Novel Wideband Antenna for High Precision Surveying

Prediction of suitable water content in granulation of sintering mixture based on Litster's model

第四届中国卫星导航学术年会

作者： Yuehua Luo Yanrui Ding qing ji Yaning Zhu Shanghai High Gain Information and Technology Co. Ltd.

In this paper, a novel wideband antenna for high precision surveying applications is proposed. Firstly, crossdipole fed by shunt type balun together with the coupling resonant elements are introduced to achieve wideband and circular polarization, the center-symmetrical structure guarantees high phase center stability, omni-directional horizontal radiation and large-angular circular polarization. On the other hand, choke ring technology is investigated;a 3D choke ring is designed to improve multipath rejection, with no deterioration of phase center stability and low elevation angle gain. The experimental results verify that the operating band covers almost all the working frequencies of the existing satellite navigation and positioning systems. The antenna demonstrates high gain, wide circular polarized beamwidth, high phase center stability, tiny phase center variation and strong multipath rejection. All these advantages qualify the antenna in wideband, multi-system and high precision applications.

关键词： cross-dipole choke ring phase center multipath rejection

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Journal of Iron and Steel Research(International) 2024年第3期31卷 552-560页

作者： Fang-lei Dai Xiao-hui Fan Xiao-xian Huang Xu-ling Chen Min Gan Zhi-yun ji Zeng-qing Sun School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

Suitable water content plays a decisive role in the granulation of sintering mixtures.Herein,a method was proposed to predict the suitable water content for effective granulation on the basis of Litster's granulation model.The granulation effectiveness of a sintering mixture was predicted by the model,with the allowance error of±10%.The effects of the water absorption properties,particle size composition and content of adhesive particles on the suitable water content were studied.The results showed that the allowable error of prediction was within±0.5%compared to the experimentally determined suitable water content.With an increase in adhesive powder content of mixtures with higher water absorption,the suitable water content increased to achieve similar granulation effectiveness.Moreover,as the amount of concentrates increased,the suitable water content first increased and then remained steady.The influence of the water absorption characteristics of the adhesive particles on the suitable water content was less than that of their particle size composition in the mixture.

关键词： Adhesive particle Sintering mixture Granulation effectiveness Suitable water content

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基于机器视觉的UUV水下沉底目标自主识别

舰船电子工程 2024年第3期44卷 168-172页

作者：庞彦东曹子健文无敌张伽伟姬庆张森李太伟张志强海军工程大学兵器工程学院武汉430070 中国人民解放军91837部队舟山316000 海军工程大学电子工程学院武汉430070

水下无人航行器对目标的自动识别研究是未来水下目标探测领域的发展趋势。针对现阶段水下沉底目标声呐图像探测人工识别工作量大、判别困难等问题,研究了机器视觉中基于Canny算子图像边缘检测结合霍夫线变换去噪的识别方法在水下无人航... 详细信息

水下无人航行器对目标的自动识别研究是未来水下目标探测领域的发展趋势。针对现阶段水下沉底目标声呐图像探测人工识别工作量大、判别困难等问题,研究了机器视觉中基于Canny算子图像边缘检测结合霍夫线变换去噪的识别方法在水下无人航行器自主探测的应用,为此在湖底布放多个水下沉底模拟目标,尝试了水下无人航行器的目标自主探测方案,通过实际湖上试验对比分析三种水下沉底目标声呐图像的算法识别效果,验证了论文所研究方法的有效性,为后续无人平台自主识别算法研究提供参考,以期提高无人航行器对水下沉底目标的自主探测识别能力。

关键词：水下无人航行器机器视觉数学形态学声呐图像

Locking Function of a Key Residue in Kinesin＇s Gating Mechanism

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Chinese Physics Letters 2014年第4期31卷 201-205页

作者： GENG Yi-Zhao ZHANG Hui ji qing YAN Shi-Wei College of Nuclear Science and Technology Beijing Normal University Beijing 100875 School of Science Hebei University of Technology Tianjin 300401 Institute of Biophysics Hebei University of Technology Tianjin 300401

In kinesin＇s mechanochemical cycle, ATP＇s binding to the nucleotide-free leading head is exquisitely gated so that futile hydrolysis is effectively avoided, Experiments show that, when both kinesin heads bind to a microtubule~ ATP cannot bind to kinesin＇s leading head when the neck linker （NL） of this head has a backward orientation. How NL＇s backward orientation is maintained needs understanding on a structural basis. By using steered molecular dynamics and rrmtation simulations, we investigate the backward-pointing conformation of the leading head＇s NL under different inter-head tensions. We find that the NL cannot keep in a strict backward orientation solely by the inter-head tension. LYS325 （amino acid sequence in 2KIN） has an assistant locking function which locks the NL and β0 to the β-domain. This locking function has an enhanced positive cooperation with the inter-head tension. When the inter-head tension is weakened, this locking function can be broken, resulting in a loose backward orientation of the NL. The difference between the strict and loose backward orientation of the NL might be a crucial factor in the gating mechanism. These results are consistent with relevant experiments and proposals.

关键词： Mechanism Locking nucleotide-free

某科研型专科医院科技成果分析及管理对策探析

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现代医院管理 2024年第3期22卷 95-99页

作者：王家乐纪庆李炳轩曾柯张艺铜刘利军祁健伟中国医学科学院血液病医院/中国医学科学院血液学研究所血液与健康全国重点实验室国家血液系统疾病临床医学研究中心细胞生态海河实验室天津市300020 天津医学健康研究院天津市301600

目的通过分析医院科技成果及管理模式,探讨科技成果管理范式,为其他医疗机构开展相关工作提供参考。方法收集某国家级科研型专科医院2013—2022年科研档案,对其获批项目、经费、专利、SCI论文、奖项等情况进行比较分析。结果2020年以来... 详细信息

目的通过分析医院科技成果及管理模式,探讨科技成果管理范式,为其他医疗机构开展相关工作提供参考。方法收集某国家级科研型专科医院2013—2022年科研档案,对其获批项目、经费、专利、SCI论文、奖项等情况进行比较分析。结果2020年以来医院申请项目、经费、授权专利、发表SCI论文和科技奖项数量有所增加。结论健全科研管理制度,制定年度科研培训计划,将成果管理融入办公自动化系统及完善科技奖励机制有助于高水平科技成果产出,助力医院提升创新能力。

关键词：科研型专科医院科研管理科技成果

Early changes in corneal densitometry after FS-LASIK combined with accelerated corneal cross-linking for correction of high myopia

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1307-1312页

作者： qing-Bao Wang Hong-Sheng Bi Xiao-Fan Wang Hua Fan Li Li Peng ji Shandong University of Traditional Chinese Medicine Jinan 250014Shandong ProvinceChina Affiliated Eye Hospital of Shandong University of Traditional Chinese Medicine Shandong Clinical Medicine Research CenterJinan 250002Shandong ProvinceChina Shandong Academy of Eye Disease Prevention and Therapy Shandong Provincial Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Therapy of Ocular DiseasesJinan 250002Shandong ProvinceChina

AIM:To observe the effects of femtosecond laserassisted excimer laser in situ keratomileusis combined with accelerated corneal cross-linking(FS-LASIK Xtra)on corneal densitometry after correcting for high myopia.METHODS:In this prospectively study,130 patients underwent FS-LASIK or FS-LASIK Xtra for high myopia.Their right eyes were selected for inclusion in the study,of which 65 cases of 65 eyes in the FS-LASIK group,65 patients with 65 eyes in the FS-LASIK Xtra group.Patients were evaluated for corneal densitometry at 1,3,and 6mo postoperatively using Pentacam Scheimpflug imaging.RESULTS:Preoperative differences in corneal densitometry between the FS-LASIK and FS-LASIK Xtra groups in different ranges were not statistically significant(P>0.05).Layer-by-layer analysis revealed statistically significant differences in the anterior(120μm),central,and total layer corneal densitometry between the FS-LASIK and FS-LASIK Xtra groups at 1 and 3mo postoperatively(all P0.05).CONCLUSION:There is an increase in internal corneal densitometry during the early postoperative period after FS-LASIK Xtra for correction of high myopia.However,the densitometry values decreased to the level of conventional FS-LASIK at 6mo after surgery,with the most significant changes observed in the superficial central zone.

关键词： femtosecond laser accelerated corneal cross-linking corneal densitometry high myopia femtosecond laser in situ keratomileusis

Suberoylanilide hydroxamic acid overcomes erlotinib-acquired resistance via phosphatase and tensin homolog deleted on chromosome 10-mediated apoptosis in non-small cell lung cancer

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Chinese Medical Journal 2020年第11期133卷 1304-1311页

作者： Peng-Fei Wu Wei-Wei Gao Cui-Lan Sun Tai Ma ji-qing Hao Department of Oncology The First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui 230022China

Background::Epidermal growth factor receptor(EGFR)tyrosine kinase inhibitors(TKIs),such as erlotinib and gefitinib,are widely used to treat non-small cell lung cancer(NSCLC).However,acquired resistance is unavoidable,impairing the anti-tumor effects of EGFR-TKIs.It is reported that histone deacetylase(HDAC)inhibitors could enhance the anti-tumor effects of other antineoplastic agents and radiotherapy.However,whether the HDAC inhibitor suberoylanilide hydroxamic acid(SAHA)can overcome erlotinib-acquired resistance is not fully clear.Methods::An erlotinib-resistant PC-9/ER cell line was established through cell maintenance in a series of erlotinib-containing cultures.NSCLC cells were co-cultured with SAHA,erlotinib,or their combination,and then the viability of cells was measured by the 3-(4,5-Dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and apoptosis was determined by flow cytometry and western blotting.Finally,the expression of phosphatase and tensin homolog deleted on chromosome 10(PTEN)was assessed by western blotting.Results::The half-maximal inhibitory concentration of parental PC-9 cells was significantly lower than the established erlotinib-acquired resistant PC-9/ER cell line.PC-9/ER cells demonstrated reduced expression of PTEN compared with PC-9 and H1975 cells,and the combination of SAHA and erlotinib significantly inhibited cell growth and increased apoptosis in both PC-9/ER and H1975 cells.Furthermore,treating PC-9/ER cells with SAHA or SAHA combined with erlotinib significantly upregulated the expression of PTEN mRNA and protein compared with erlotinib treatment alone.Conclusions::PTEN deletion is closely related to acquired resistance to EGFR-TKIs,and treatment with the combination of SAHA and erlotinib showed a greater inhibitory effect on NSCLC cells than single-drug therapy.SAHA enhances the suppressive effects of erlotinib in lung cancer cells,increasing cellular apoptosis and PTEN expression.SAHA can be a potential adjuvant to erlotinib treatment,and thus,can improve the effica

关键词： Acquired resistance Erlotinib Histone deacetylase Lung cancer SAHA

Retrospective Analysis of Ultrasound-guided Flexible Ureteroscopy in the Management of Calyceal Diverticular Calculi

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Chinese Medical Journal 2016年第17期129卷 2067-2073页

作者： ji-qing Zhang Yong Wang Jun-Hui Zhang Xiao-Dong Zhang Nian-Zeng Xing Department of Urology Beijing Chaoyang Hospital Capital Medicar University Beijing 100020 China

Background： Percutaneous nephrolithotomy （PCNL） is the most widely recommended treatment lbr calyceal diverticular calculi, providing excellent stone-free results. However, its invasiveness is not negligible considering its major complication rates. Flexible ureteroscopy （FURS） is currently used to treat calyceal diverticula. However, the greatest drawback of FURS is locating the diverticulum since its neck is narrow and concealed. In such a case, the FURS procedure must be converted to PCNL. The aim of this study was to evaluate ultrasound-guided flexible ureteroscopy （UFURS） identifying diverticulum and the managenlent of calyceal diverticular calculi. Methods： A retrospective analysis was conducted on 24 patients who had calyceal diverticnlar calculi. In all 12 patients in tile UFURS group, direct FURS failed to find evidence of calyceal diverticula but were confirmed with imaging. The other 12 patients in the PCNL group received PCNL plus fulguration of the divenicular walls. Results： Puncture ofcalyceal diverticulum was successful in all 12 UFURS patients. Two patients in this group had postoperative residual calculi and two patients developed lever. In the PCNL group, percutaneous renal access and lithotomy were successful in all 12 patients. One patient in this group had residual calculi, one had perirenal hematoma, and two patients developed fever. No significant difference was found in the operating time （UFURS vs. PCNL, 91.8 ± 24.2 vs. 86.3 ± 18.7 min）, stone-free rate （UFURS vs. PCNL, 9/12 vs. 10/12）, and rate of successful lithotripsy （UFURS vs. PCNL, 10/12 vs. 11/12） between the two groups （all P 〉 0.05）. Postoperative pain scores in the FURS group were significantly lower than that in the PCNL group （2.7 ±1.2 vs. 6.2 ±1.5. P 〈 0.05）. Hospital stay in the UFURS group was significantly shorter than that in the PCNL group （3.4 ± 0.8 vs. 5.4 ± 1.0 days, P 〈 0.05）. All patients were symptom-free following surgery （UFURS vs. PCNL, 10/10 vs. 12/12）. Conclusion： Ultrasound-guided puncture facilitates identi

关键词： Calyceal Diverticulum Calyceal Diverticulum Calculi Flexible Ureteroscope Percutaneous Nephrolithotonly Puncture Ultrasound

基于UPLC-Q-TOF-MS/MS的“略麻1号”茎秆与块茎化学成分分析

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中国现代中药 2024年第5期26卷 788-798页

作者：李炳佳贺文文白吉庆王小平李军茂李晓东江西中医药大学江西南昌330000 陕西省中药原料质量监测技术服务中心陕西咸阳712046 陕西中医药大学陕西咸阳712046 略阳县中药材产业发展中心陕西汉中724300

目的:对“略麻1号”茎秆与块茎化学成分进行比较研究。方法:采用超高效液相色谱-四极杆飞行时间质谱法(UPLC-Q-TOF-MS/MS),Xbridge BEH C_(18)色谱柱(100 mm×2.1 mm,1.7μm),以0.1%甲酸水溶液-乙腈为流动相进行梯度洗脱,流速为0.3 mL·... 详细信息

目的:对“略麻1号”茎秆与块茎化学成分进行比较研究。方法:采用超高效液相色谱-四极杆飞行时间质谱法(UPLC-Q-TOF-MS/MS),Xbridge BEH C_(18)色谱柱(100 mm×2.1 mm,1.7μm),以0.1%甲酸水溶液-乙腈为流动相进行梯度洗脱,流速为0.3 mL·min^(–1);扫描方式采用正、负离子Full-ddMS2模式下采集数据;结合对照品、相关文献及质谱裂解规律对样品中成分的二级质谱数据进行分析。结果:从“略麻1号”茎秆中共鉴定出153个化合物,包括酚类20个、有机酸类46个、黄酮类11个、氨基酸类12个、生物碱类14个、其他类50个;从“略麻1号”块茎中共鉴定出126个化合物,包括酚类21个、有机酸类36个、氨基酸类13个、生物碱类11个、其他类45个。结论:“略麻1号”茎秆和块茎在物质基础上差异较大,在开发应用中应予以区别,茎秆具有较高的开发应用价值。

关键词：超高效液相色谱-四极杆飞行时间质谱法天麻茎秆化学成分质谱裂解规律酚类