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基于drop-off ddPCR方法检测急性髓系白血病C-KIT基因N822位点突变及其临床应用
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作者 李婷 金晔 +7 位作者 袁倩 姚冬明 向鹤麟 肖高飞 于迪 冷加燕 林江 钱军 《江苏大学学报(医学版)》 CAS 2024年第2期151-155,160,共6页
目的:建立急性髓系白血病(acute myeloid leukemia, AML)患者C-KIT基因N822位点突变的drop-off微滴式数字PCR(droplet digital PCR,ddPCR)定量检测方法,并评价其临床应用价值。方法:针对C-KIT基因第17外显子设计一对引物及探针,优化drop... 目的:建立急性髓系白血病(acute myeloid leukemia, AML)患者C-KIT基因N822位点突变的drop-off微滴式数字PCR(droplet digital PCR,ddPCR)定量检测方法,并评价其临床应用价值。方法:针对C-KIT基因第17外显子设计一对引物及探针,优化drop-off ddPCR反应条件及体系,评价该方法的特异性、灵敏度、重复性,使用所建立的方法对140例已行Sanger测序的AML初诊患者骨髓标本进行检测,并用二代测序(next generation sequencing, NGS)验证结果;用drop-off ddPCR对3例阳性患者化疗后C-KIT突变频率进行动态监测。结果:drop-off ddPCR检测C-KIT基因N822位点突变的最适退火温度为54℃,空白检测限为1.62拷贝数/μL,最低检测下限为10.12拷贝数/μL,线性良好。140例AML初诊患者样本中Sanger测序检出2例阳性(1.4%),而ddPCR共检出突变7例(5.0%),突变频率为0.29%~7.41%;进一步应用常规NGS方法对ddPCR阳性样本进行验证,共检出阳性3例(2.1%),等位基因频率为1.26%~8.00%。动态监测3例阳性患者C-KIT突变频率,结果显示治疗达完全缓解时C-KIT突变频率明显下降甚至降低至0。结论:本研究建立了检测C-KIT基因N822位点突变的drop-off ddPCR技术,具有良好的方法学检测性能,其灵敏度高于Sanger测序和NGS,有望用于阳性患者缓解后的可检测残留疾病监测及治疗指导。 展开更多
关键词 drop-off微滴式数字PCR C-KIT基因 基因突变 微小残留病 急性髓系白血病 预后
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Drop-off微滴式数字PCR检测急性髓系白血病NRAS基因突变及其临床应用 被引量:1
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作者 向鹤麟 金晔 +6 位作者 袁倩 姚冬明 李婷 于迪 冷加燕 林江 钱军 《江苏大学学报(医学版)》 CAS 2023年第1期49-53,共5页
目的:建立检测急性髓系白血病(acute myeloid leukemia,AML)神经母细胞瘤RAS病毒癌基因同源物(NRAS)基因突变的drop-off微滴式数字PCR(droplet digital PCR,ddPCR)方法,并评价该方法的临床应用价值。方法:针对NRAS G12和G13突变位点设... 目的:建立检测急性髓系白血病(acute myeloid leukemia,AML)神经母细胞瘤RAS病毒癌基因同源物(NRAS)基因突变的drop-off微滴式数字PCR(droplet digital PCR,ddPCR)方法,并评价该方法的临床应用价值。方法:针对NRAS G12和G13突变位点设计特异性drop-off ddPCR引物和探针,建立最佳反应体系,并对该方法进行性能验证。应用该方法对140例临床样本进行初筛,其检测结果与Sanger测序进行比较,并用二代测序(next generation sequencing,NGS)进行验证。结果:建立drop-off ddPCR检测NRAS基因G12/G13突变的方法,灵敏度达0.158%,重复性、线性良好,其空白限为5.40拷贝数/μL,最低检测下限为15.84拷贝数/μL。在140例初诊AML患者中,drop-off ddPCR检出NRAS突变28例(20%),其突变负荷为0.26%~52.85%(中位2.14%);而Sanger测序仅检出7例(5%)阳性,为进一步验证,将21例Sanger测序结果阴性而drop-off ddPCR检测阳性的样本进行NRAS基因NGS,检出14例阳性,而另外7例NGS阴性的样本,其drop-off ddPCR检测突变频率为0.53%~1.50%(中位1.10%)。结论:建立了drop-off ddPCR技术检测AML患者中NRAS基因突变的方法,该方法灵敏度高,可用于对NRAS基因G12/G13突变进行定量检测,有望可用于AML患者预后判断和疾病监测。 展开更多
关键词 drop-off微滴式数字PCR NRAS基因 急性髓系白血病 基因突变 微小残留病灶 预后
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外科模板结合Pick-up技术在无牙颌即刻负重种植修复中的临床应用 被引量:7
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作者 耿威 马攀 +2 位作者 李钧 刘长营 谭包生 《口腔颌面修复学杂志》 2015年第4期212-217,共6页
目的:探讨应用种植外科模板结合Pick-up技术进行无牙颌即刻负重种植修复,评估应用Pick-up技术使预先制作的修复体即刻负重的可行性及临床效果。方法:9例无牙颌患者采用带有预成修复体信息的种植外科模板引导种植体植入,而后应用预成的... 目的:探讨应用种植外科模板结合Pick-up技术进行无牙颌即刻负重种植修复,评估应用Pick-up技术使预先制作的修复体即刻负重的可行性及临床效果。方法:9例无牙颌患者采用带有预成修复体信息的种植外科模板引导种植体植入,而后应用预成的修复体结合Pick-up技术制作种植体支持的临时修复体,完成无牙颌即刻负重修复。随访临时修复体功能状况,总结Pick-up技术的就诊次数、被动就位情况、颌位关系、患者满意度。6个月后进行永久修复,定期随访观察种植体存留情况,种植体周围边缘骨吸收情况和种植体支持的修复体应用状况。结果:9例患者共植入56枚种植体,1颗种植体脱落,53颗种植体即刻负重,完成下颌6个、上颌3个种植体支持的树脂材料临时修复体。随访时间12-60个月(平均36个月),全部即刻负重的种植体稳定无松动,种植体边缘骨吸收0.5±0.24m m,即刻负重种植体存留率100%。全部种植体存留率98.2%,全部永久修复体均正常行使功能。利用种植外科模板通过Pick-up技术进行即刻负重修复治疗时间短,就诊次数少,一次获得被动就位,颌位关系准确,患者满意度高。结论:种植外科模板结合Pick-up技术进行种植体的即刻负重修复,可实现微创准确快速的种植治疗,临床效果满意。 展开更多
关键词 牙种植 牙列缺失 即刻负重 外科模板 pick-up技术
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Basic Research on the Burden of Dropping off and Picking up Children: Differences by Employment Type and Gender in the Tokyo Metropolitan Area
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作者 Jun Morio Koshi Isono +1 位作者 Masahiko Kikuchi Tetsuo Morita 《Journal of Transportation Technologies》 2024年第3期445-461,共17页
There is a need to reduce the burden of child drop-off and pick-up for child-rearing generations, but most studies on the actual situation in Japan are based on survey results. In this study, we analyzed differences i... There is a need to reduce the burden of child drop-off and pick-up for child-rearing generations, but most studies on the actual situation in Japan are based on survey results. In this study, we analyzed differences in child drop-off and pick-up by employment type and gender, utilizing the “Metropolitan Area Person Trip Survey,” which is a statistical data set. The study targeted households in which both spouses were between 30 and 49 years old, had children under the age of 6, and included the following three groups. 1) Dual-income Group 1 (both spouses employed/on contract/temporary);2) Dual-income Group 2 (husband employed/on contract/temporary, wife part-time);3) Full-time housewife group (husband employed, wife unemployed). The analysis revealed that a) wives are almost always responsible for dropping off and picking up their children;b) husbands drop off and pick up their children less frequently in dual-income households;and c) households with children raising within 10 to 30 km of Tokyo Station have longer commuting times and need to reduce the burden of dropping off and picking up their children. 展开更多
关键词 drop-off and pick-up Employment Type GENDER Dual-Income Households Tokyo Metropolitan Area
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数字化导板与pick-up技术在牙列缺失种植修复中的应用1例 被引量:3
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作者 张凯悦 赵保东 +1 位作者 韩泽禹 滕敏华 《中华老年口腔医学杂志》 2022年第6期348-352,共5页
随着经济及医学水平的高速发展,我国老年无牙颌患者呈逐年上升趋势。常规全口义齿修复存在诸多缺点,不能满足于老年无牙颌患者的生活需求[1]。种植体支持的固定全口义齿修复被证明是恢复无牙颌患者面部美学及功能、提高患者生活质量的... 随着经济及医学水平的高速发展,我国老年无牙颌患者呈逐年上升趋势。常规全口义齿修复存在诸多缺点,不能满足于老年无牙颌患者的生活需求[1]。种植体支持的固定全口义齿修复被证明是恢复无牙颌患者面部美学及功能、提高患者生活质量的有效治疗手段[2]。而数字化导板可帮助引导种植体精确就位,防止损伤邻近软硬组织等重要的解剖结构,确保种植体达到设计的位置、深度及角度,更有助于符合生物学为导向的种植治疗理念[3-4]。而即刻修复缩短了空牙期,满足了患者即刻恢复美观的需求。 展开更多
关键词 种植牙 牙列缺失 数字化导板 计算机辅助外科 pick-up技术 种植即刻负重
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Design and Experimental Research on Seedling Pick-Up Mechanism of Planetary Gear Train with Combined Non-circular Gear Transmission 被引量:9
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作者 Yaxin Yu Jikun Liu +4 位作者 Bingliang Ye Gaohong Yu Xuejun Jin Liang Sun Junhua Tong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第3期42-54,共13页
Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent ... Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent transmission, and a concave and convex locking arc device, has a large rigid impact. To solve these problems, according to the design requirements for a dryland plug seedling transplanting mechanism, a rotary seedling pick-up mechanism of a planetary gear train with combined non-circular gear transmission of incomplete eccentric circular and noncircular gears was proposed. This has the characteristics of two-times greater fluctuation of the transmission ratio in a cycle, and can achieve a non-uniform continuous drive. Through analysis of the working principle of the seedling pick-up mechanism, its kinematics model was established. The human–computer interaction optimization method and self-developed computer-aided analysis and optimization software were used to obtain a set of parameters that satisfy the operation requirements of the seedling pick-up mechanism. According to the optimized parameters, the structure of the seedling pick-up mechanism was designed, a virtual prototype of the mechanism was created, and a physical prototype was manufactured. A virtual motion simulation of the mechanism was performed, high-speed photographic kinematics tests were conducted, and the kinematic properties of the physical prototype were investigated, whereby the correctness of the theoretical model and the optimized design of the mechanism were verified. Further, laboratory seedling pick-up tests were conducted. The success ratio of seedling pick-up was 93.8% when the seedling pick-up efficiency of the mechanism was 60 plants per minute per row, indicating that the mechanism has a high efficiency and success ratio for seedling pick-up and can be applied to a dryland plug seedling transplanter. 展开更多
关键词 Dryland plug SEEDLING transplanter Rotary SEEDLING pick-up MECHANISM TRANSMISSION ratio Non-uniform continuous TRANSMISSION COMBINED NON-CIRCULAR gear TRANSMISSION Optimization design
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Astronomical Tables in the“Lü-li zhi”:On the Characteristics and Adoption of“Licheng”Pick-up Tables 被引量:2
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作者 李亮 《Chinese Annals of History of Science and Technology》 2018年第2期41-71,共31页
This article discusses the development of astronomical tables in ancient China based on the calendrical chapter titled“Lü-li zhi”律曆志(Monograph on harmonics and calendrical astronomy)in official histories.Aft... This article discusses the development of astronomical tables in ancient China based on the calendrical chapter titled“Lü-li zhi”律曆志(Monograph on harmonics and calendrical astronomy)in official histories.After surveying various types of astral scientific tables in ancient China and their layouts,this paper discusses the characteristics and adoption of“licheng”立成tables,a specific kind of pick-up table that seems to have come into use in the Sui period(581–618)and to have been widespread from the Tang period(618–907)onward.The emergence of licheng tables relates largely to the internal development of ancient Chinese astronomy,but they were also probably inspired by auspicial tables and foreign astronomical tables.By comparing tables recorded in the“Lü-li zhi”and the existing licheng tables,we find that most licheng were deleted during the compilation of“Lü-li zhi”to reduce the number of volumes.Moreover,this paper discusses several common solutions used to compress the size of tables in“Lü-li zhi.”The adoption of licheng tables into the ancient Chinese astral sciences and the reformatting of them in“Lü-li zhi”give us a different perspective for understanding the development of ancient Chinese astronomical tables and the compilation of the calendrical portion of official histories. 展开更多
关键词 “Lü-li zhi” pick-up table“licheng” astronomical tables
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Cause analysis of and solution to furnace roller pick-up in the high strength automotive steel sheet processing line
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作者 WANG Lu 《Baosteel Technical Research》 CAS 2013年第2期44-48,共5页
Cold-rolled high strength steel sheets for automobiles contain more Mn and Si based alloy elements, which, under the reducing atmosphere in the annealing furnace, will get enriched on the strip surface. Since the furn... Cold-rolled high strength steel sheets for automobiles contain more Mn and Si based alloy elements, which, under the reducing atmosphere in the annealing furnace, will get enriched on the strip surface. Since the furnace rollers and the strips contact frequently, alloy elements on the roller surface will form hard protuberance. We call this protuberance "pick-up". In addition, with the increase of the amount of dust in the furnace atmosphere, the occurrence of furnace roller pick-up will also increase. Through chemical reaction and physical accumulation analysis combined with practical experience, the causes of pick-up in different furnace sections were analyzed. Methods of preventing furnace roller pick-up in the high strength steel sheet processing line were discussed and solutions to improving the strip surface quality in the continous annealing furnace were provided. 展开更多
关键词 high strength steel continuous annealing furnace roller pick-up furnace atmosphere cleanliness
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关于pick-up的常见问题
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作者 魏国 《乐器》 2003年第7期74-75,共2页
电吉他pick-up的发明是为了使吉他发出更大的声音,也因此有了所谓"电"吉他.我们可以视之为一种能量的转换装置,对音色有很大影响.早期研究发展pick-up多在Fender、Gibson为主的大公司内进行,不同于今日百家争鸣的局面.
关键词 电吉他 pick-up 音色 拾音器 线圈 缠绕方法
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Hypotension after intensive care unit drop-off in adult cardiac surgery patients
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作者 Sabina Cengic Muhammad Zuberi +3 位作者 Vikas Bansal Robert Ratzlaff Eduardo Rodrigues Emir Festic 《World Journal of Critical Care Medicine》 2020年第2期20-30,共11页
BACKGROUND Hypotension is a frequent complication in the intensive care unit(ICU)after adult cardiac surgery.AIM To describe frequency of hypotension in the ICU following adult cardiac surgery and its relation to the ... BACKGROUND Hypotension is a frequent complication in the intensive care unit(ICU)after adult cardiac surgery.AIM To describe frequency of hypotension in the ICU following adult cardiac surgery and its relation to the hospital outcomes.METHODS A retrospective study of post-cardiac adult surgical patients at a tertiary academic medical center in a two-year period.We abstracted baseline demographics,comorbidities,and all pertinent clinical variables.The primary predictor variable was the development of hypotension within the first 30 min upon arrival to the ICU from the operating room(OR).The primary outcome was hospital mortality,and other outcomes included duration of mechanical ventilation(MV)in hours,and ICU and hospital length of stay in days.RESULTS Of 417 patients,more than half(54%)experienced hypotension within 30 min upon arrival to the ICU.Presence of OR hypotension immediately prior to ICU transfer was significantly associated with ICU hypotension(odds ratio=1.9;95%confidence interval:1.21-2.98;P<0.006).ICU hypotensive patients had longer MV,5(interquartile ranges 3,15)vs 4 h(interquartile ranges 3,6),P=0.012.The patients who received vasopressor boluses(n=212)were more likely to experience ICU drop-off hypotension(odds ratio=1.45,95%confidence interval:0.98-2.13;P=0.062),and they experienced longer MV,ICU and hospital length of stay(P<0.001,for all).CONCLUSION Hypotension upon anesthesia-to-ICU drop-off is more frequent than previously reported and may be associated with adverse clinical outcomes. 展开更多
关键词 HYPOTENSION Cardiac surgery Intensive care Postoperative care Care transfer drop-off
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Improvement of Pick-up Mechanism for Composite Particle Emissions
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《Chinese journal of nuclear physics》 1996年第1期29-33,共5页
ImprovementofPick┐upMechanismforCompositeParticleEmisionsZhangJingshangandZhouSuijianChinaInstituteofAtomicE... ImprovementofPick┐upMechanismforCompositeParticleEmisionsZhangJingshangandZhouSuijianChinaInstituteofAtomicEnergy,P.O.Box275(... 展开更多
关键词 pick-up COMPOSITE EMISSIONS IMPROVEMENT MECHANISM
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北京谱仪-Ⅱ主漂移室干扰噪声的研究 被引量:2
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作者 王运永 王少敏 +17 位作者 毛慧顺 刘荣光 宋晓非 李金 李卫国 李小南 李如柏 吕军光 张健 张德红 金艳 杨杰 黄俊东 柯尊建 高树琦 谢佩佩 顾建辉 颜洁 《核电子学与探测技术》 CAS CSCD 北大核心 1999年第3期201-205,共5页
研究了北京谱仪-Ⅱ主漂移室干扰噪声(pick-up噪声)的主要表现形式,分析了噪声的来源,提出了解决办法。
关键词 北京谱仪 主漂移室 pick-up噪声 干扰噪声
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全牙弓种植即刻修复方案选择决策树 被引量:2
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作者 彭玲燕 王勇 宿玉成 《中国口腔种植学杂志》 2022年第6期381-386,共6页
对于无法保留口内所有天然牙的牙列缺失患者,全牙弓种植即刻固定修复能在尽量短的时间内恢复患者的咀嚼、发音功能。随着新的技术、设备和软件不断涌现,临床上在应用该技术时存在一定困惑和混乱。为了规范化该方案的使用,为患者提供多... 对于无法保留口内所有天然牙的牙列缺失患者,全牙弓种植即刻固定修复能在尽量短的时间内恢复患者的咀嚼、发音功能。随着新的技术、设备和软件不断涌现,临床上在应用该技术时存在一定困惑和混乱。为了规范化该方案的使用,为患者提供多种方案选择,根据本杂志2022年6月刊登的《全牙列种植即刻临时修复方案选择》一文,作者团队进一步深化总结出当前适用于解决该类临床病例的决策树,以期为种植修复医生对此类病例进行诊断治疗时提供建议和参考,医生可根据患者临床情况、医生经验以及所具有的技术设备和软件等综合条件进行决策。 展开更多
关键词 预成修复体 数字化印模 pick-up技术 即刻修复 全牙弓
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Design of Vegetable Pot Seedling Pick‑up Mechanism with Planetary Gear Train 被引量:7
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作者 Zhipeng Tong Gaohong Yu +2 位作者 Xiong Zhao Pengfei Liu Bingliang Ye 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第4期87-97,共11页
It has been challenging to design seedling pick-up mechanism based on given key points and trajectories,because it involves dimensional synthesis and rod length optimization.In this paper,the dimensional synthesis of ... It has been challenging to design seedling pick-up mechanism based on given key points and trajectories,because it involves dimensional synthesis and rod length optimization.In this paper,the dimensional synthesis of seedling pickup mechanism with planetary gear train was studied based on the data of given key points and the trajectory of the endpoint of seedling pick-up mechanism.Given the positions and orientations requirements of the five key points,the study first conducted a dimensional synthesis of the linkage size and center of rotation.The next steps were to select a reasonable solution and optimize the data values based on the ideal seedling trajectory.The link motion was driven by the planetary gear train of the two-stage gear.Four pitch curves of noncircular gears were obtained by calculating and distributing the transmission ratio according to the data.For the pitch curve with two convex points,the tooth profile design method of incomplete noncircular gear was applied.The seedling pick-up mechanism was tested by a virtual prototype and a physical prototype designed with the obtained parameter values.The results were consistent with the theoretical design requirements,confirming that the mechanism meets the expected requirements for picking seedlings up.This paper presents a new design method of vegetable pot seedling pick-up mechanism for an automatic vegetable transplanter. 展开更多
关键词 Combined incomplete noncircular gear Mechanism dimension synthesis Planetary gear train Seedling pick-up mechanism
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Reverse design and tests of vegetable plug seedling pick-up mechanism of planetary gear train with non-circular gears 被引量:2
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作者 Zhifang Zhu Guohuan Wu +1 位作者 Bingliang Ye Yongchang Zhang 《International Journal of Agricultural and Biological Engineering》 SCIE 2023年第2期96-102,共7页
In the previous research,the seedling pick-up mechanism of the planetary gear train with incomplete eccentric circular gear and non-circular gears for vegetable plug seedlings still has two shortcomings.One is that no... In the previous research,the seedling pick-up mechanism of the planetary gear train with incomplete eccentric circular gear and non-circular gears for vegetable plug seedlings still has two shortcomings.One is that not enough seedling pick-up depth leads to a low success ratio of seedling pick-up at high rotation speeds,the other is that the smaller seedling pushing angle results in poor seedling pushing effect.Therefore,the reverse design of the seedling pick-up mechanism based on its motion trajectory was carried out.The local trajectory of seedling pick-up and seedling pushing sections was adjusted to obtain the theoretical motion trajectory of the seedling pick-up mechanism.The cubic non-uniform B-spline curve was used to fit the adjusted trajectory.A novel seedling pick-up mechanism of the planetary gear train with non-circular gears was proposed,including three combined non-circular gears,four non-circular gears,one planetary carrier,and two seedling pick-up arms.The reverse design model of the mechanism was established.The analysis and design software of the mechanism was developed to obtain the mechanism parameters meeting design requirements.The virtual prototype of the mechanism was established and its physical prototype was manufactured.Through the virtual motion simulation and high-speed photographic kinematics bench tests of the mechanism,the kinematic model and results of reverse design of the mechanism were verified,with the kinematic performances of the mechanism prototype studied.The seedling pick-up tests of the mechanism were conducted in the laboratory.The success ratios of seedling pick-up were 94.2%,95.6% and 90.2% while the seedling pick-up efficiencies of the mechanism were 60,80 and 100 plants per minute per row,respectively.Besides,the seedling pushing effect was improved mush because of the greater seedling pushing angle.The seedling pick-up mechanism through revise design is of high value to be applied in the practical vegetable plug seedling transplanters. 展开更多
关键词 vegetable plug seedling seedling pick-up mechanism non-circular gear reverse design virtual simulation seedling pick-up tests
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An Entropy-Based Model for Recommendation of Taxis’Cruising Route 被引量:1
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作者 Yizhi Liu Xuesong Wang +3 位作者 Jianxun Liu Zhuhua Liao Yijiang Zhao Jianjun Wang 《Journal on Artificial Intelligence》 2020年第3期137-148,共12页
Cruising route recommendation based on trajectory mining can improve taxi-drivers'income and reduce energy consumption.However,existing methods mostly recommend pick-up points for taxis only.Moreover,their perform... Cruising route recommendation based on trajectory mining can improve taxi-drivers'income and reduce energy consumption.However,existing methods mostly recommend pick-up points for taxis only.Moreover,their performance is not good enough since there lacks a good evaluation model for the pick-up points.Therefore,we propose an entropy-based model for recommendation of taxis'cruising route.Firstly,we select more positional attributes from historical pick-up points in order to obtain accurate spatial-temporal features.Secondly,the information entropy of spatial-temporal features is integrated in the evaluation model.Then it is applied for getting the next pick-up points and further recommending a series of successive points.These points are constructed a cruising route for taxi-drivers.Experimental results show that our method is able to obviously improve the recommendation accuracy of pick-up points,and help taxi-drivers make profitable benefits more than before. 展开更多
关键词 Trajectory data mining location-based services(LBS) optimal route recommendation pick-up point recommendation information entropy
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Characterization of blood flow and the effects of exogenous estradiol benzoate on residual follicles formed after ultrasound-guided transvaginal follicle aspiration in cattle
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作者 Alberto Mansur Ghetti Luiz Gustavo Bruno Siqueira +3 位作者 Eduardo Kenji Nunes Arashiro Miller Pereira Palhao Felipe Zandonadi Brandao Joao Henrique Moreira Viana 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2017年第1期51-56,共6页
Background: Removal of the follicular content by ultrasound-guided transvaginal follicle aspiration(TVFA) may fail to induce immediate atresia and loss of function, resulting in the occurrence of residual follicles... Background: Removal of the follicular content by ultrasound-guided transvaginal follicle aspiration(TVFA) may fail to induce immediate atresia and loss of function, resulting in the occurrence of residual follicles(RF). The aims of this study were to characterize the blood flow in RF and to determine the effects of the treatment with estradiol benzoate on RF fate. Lactating, cyclic Holstein-Gir crossbred cows were used. In Experiment 1, follicular wave emergence(D0) was synchronized in cows(n = 10) and follicular growth was then monitored by transrectal ultrasonography from D0 to D8, followed by TVFA of the largest follicle present on the ovaries 24 h later. Color Doppler ultrasound imaging was used to examine blood flow on the follicular wall, which was recorded immediately before and every 12 h after TVFA, up to 72 h. In experiment 2, cows(n = 22) were randomly allocated to receive either 2 mL of saline i.m.(Control group, n = 11) or 2 mL estradiol benzoate i.m.(EB group, n = 11)immediately after TVFA. Ovaries were scanned every 12 h to confirm the presence and to measure the diameter of RF. The contents of the RF, if present, were collected 72 h after the first TVFA, using the same aspiration procedures.Follicular fluid from original follicles and RF were stored at-20 °C until hormonal assays.Results: In Experiment 1, there was no reduction(P 〉 0.05) of blood flow in the remaining follicle walls after TVFA and maximum blood flow values were observed at 49.5 ± 19.7 h post-TVFA. In Experiment 2, formation of RF after TVFA was proportionally similar between Controls(5/9) and EB(5/10) cows. Also, RF diameter did not differ between groups(P 〉 0.05). Nonetheless, the content of RF from cows in the EB group had lower(P = 0.0004)estradiol(E2) concentration and lower(P = 0.0005) E2:P4 ratio compared with Controls.Conclusions: In conclusion, 1) the persistence of vascularization in the remaining follicle wall may contribute to the formation of RF after follicle aspiration, and 2) the treatment with estradiol benzoate does not prevent formation of RF,but does reduce their estradiol production. 展开更多
关键词 Doppler Ovary Ovum pick-up Steroidogenesis Vascularization
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如何使用pick up
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作者 冯传胜 《英语学习辅导(高考指导版)》 2000年第3期11-11,共1页
关键词 高中 英语 pick-up 词组 用法
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Performances and Rotating Flows of Rotary Jet Pump
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作者 Keiichi Komaki Toshiaki Kanemoto Kenji Sagara 《Open Journal of Fluid Dynamics》 2012年第4期375-379,共5页
The rotary jet pumps, namely the pitot pumps, are composed of the rotating casing with the impeller channels and the stationary pick-up tube for discharging, are known as the one of high pressure pumps in the U.S. mar... The rotary jet pumps, namely the pitot pumps, are composed of the rotating casing with the impeller channels and the stationary pick-up tube for discharging, are known as the one of high pressure pumps in the U.S. market. The pumps, however, have been prepared experientially, because of poor knowledge for the flow conditions and the pump performances. Then, this paper discusses the pump performances and the internal flow conditions in the rotating casing. Three types of the pick-up tube were prepared for the experiments to know the pump performances and the flow conditions in the rotating casing. The flow in the rotating casing is nearly in the forced vortex type and gives the higher pressure at the pick-up tube inlet. The more cross-sectional area of the pick-up tube channel is large, the more head and discharge are higher with excellent efficiency. Moreover, the authors confirmed that the secondary flow runs toward the rotating center at the wake flow region behind the pick-up tube. 展开更多
关键词 Rotation CASING Type PUMP Pitot PUMP High Pressure PUMP pick-up Tube FORCED VORTEX Secondary Flow
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Design and test of the arc-shaped nail-tooth roller residual film recovery machine from the sowing layer
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作者 Zhiyuan Zhang Xuegeng Chen +2 位作者 Xianfei Wang Shuaikang Xue Jingbin Li 《International Journal of Agricultural and Biological Engineering》 SCIE 2024年第1期90-98,共9页
Residual films on the sowing layer produced after mulching in Xinjiang farmland,harm the sowing quality and root growth of crops.In this study,a sowing layer residual film recovery machine based on a radial plate arc-... Residual films on the sowing layer produced after mulching in Xinjiang farmland,harm the sowing quality and root growth of crops.In this study,a sowing layer residual film recovery machine based on a radial plate arc-shaped nail-tooth roller structure was designed.Meanwhile,the key device structures were designed and the main working parameters were analyzed.Then,taking the working depth,the forward speed of the machine and the rotation speed of the nail tooth roller as the test factors,and the film collection rate and film intertwining rate as the test indicators,the single factor tests and the Box-Behnken response surface tests were carried out to evaluate the performance of the sowing layer residual film recovery machine.Consequently,the results showed that the order of significant factors was the working depth,the forward speed of the machine,and the rotation speed of the nail tooth roller.Besides,the optimal working parameters were determined,which the working depth,the forward speed of the machine,and the rotation speed of the nail tooth roller were 100 mm,4.8 km/h,and 49.3 r/min,respectively.Moreover,the predicted value of the film collection rate was 69.20%.Finally,the verification test was taken with the optimal working parameter,and the results showed that the film collection rate was 66.84%,and the film intertwining rate was 1.39%.The relative error between the test value and the predicted value of the film collection rate was 3.40%.It indicated that the machine can perform the collection of sowing layer residual films.This study can provide a theoretical basis and reference for the design of new sowing layer residual film machines. 展开更多
关键词 residual film recycling machine mulching film pick-up device seedbed preparation
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