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Detection of Homozygous Deletions and Mutations in the CDKN2A Gene in Hydatidiform Moles
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作者 Jing Wang Shuying Wu +2 位作者 Ying Gu Yan Zhu Xiaowei Zhang 《Chinese Journal of Clinical Oncology》 CSCD 2008年第2期99-102,共4页
OBJECTIVE To investigate homozygous deletions and mutations in the CDKN2A gene(p16 INK4a and p14 ARF gene)in hydatidiform moles. METHODS A total of 38 hydatidiform mole samples and 30 villi samples were examined for h... OBJECTIVE To investigate homozygous deletions and mutations in the CDKN2A gene(p16 INK4a and p14 ARF gene)in hydatidiform moles. METHODS A total of 38 hydatidiform mole samples and 30 villi samples were examined for homozygous deletions in the CDKN2A gene by PCR and for mutations by DHPLC. RESULTS i)Among 38 hydatidiform mole samples, homozygous deletions in the p16 INK4a exon 1 were identified in 5 cases(13.2%),while no homozygous deletions were found in the p16I NK4aexon 1 of 30 early-pregnancy samples.The rates of those deletions in hydatidiform compared to early-pregnancy villi samples was statistically significant(P=0.036).ii)No homozygous deletions in the p14 ARF exon 1 or p16 INK4a exon 2 were found in any of the hydatidiform moles or early-preganancy samples.iii) In all hydatidiform moles and early-pregnancy villi samples,no mutations were detected by DHPLC. CONCLUSION We suggest there may be a close correlation between homozygous deletions in the CDKN2A gene and occurrence of hydatidiform moles variation in the CDKN2A gene is mainly caused by homozygous deletions,while mutations may be not a major cause. 展开更多
关键词 hydatidiform mole CDKN2A gene homozygous deletion mutation.
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Single Nucleotide Polymorphism-Based Chromosomal Microarray Evaluation of Hydatidiform Moles: A US National Reference Laboratory Experience
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作者 Arturo Anguiano Boris T. Wang +4 位作者 Kylin Y. Lammers Loretta W. Mahon Nicole Truitt Lindsay Dohany Fatih Z. Boyar 《Open Journal of Obstetrics and Gynecology》 2020年第8期1122-1134,共13页
<strong>Objectives</strong>:<span> This retrospective study evaluated 1) benefits of single nucleotide polymorphism (SNP)-based chromosomal microarrays (CMAs) in the diagnosis of complete hydatidifor... <strong>Objectives</strong>:<span> This retrospective study evaluated 1) benefits of single nucleotide polymorphism (SNP)-based chromosomal microarrays (CMAs) in the diagnosis of complete hydatidiform mole (CHM) and partial HM (PHM) in products of conception (POC) and amniotic fluid (AF) specimens, and 2) frequency of whole-genome uniparental disomy (wgUPD) and triploidy in POC and AF specimens received at a US national reference laboratory.</span><span "=""> </span><b><span>Methods:</span></b><span> We reviewed consecutive 2138 POC and 3230 AF specimens and identified the cases with wgUPD and triploidy which are associated with molar pregnancy.</span><span "=""> </span><b><span>Results:</span></b><span "=""><span> Of 2138 consecutive POC specimens tested, SNP-based CMA detected wgUPD in 10 (0.47%) and triploidy in 84 (3.93%). Of the 10 wgUPD cases, 9 (90%) were confirmed as CHM. Of 3230 consecutive AF specimens, the array detected wgUPD in 1 case (0.03%) and triploidy in 11 (0.34%). </span><b><span>Conclusions:</span></b><span> SNP-based microarray allows detection of wgUPD in POC and AF specimens at a US national reference laboratory. Correctly diagnosing HM and differentiating CHM from PHM </span></span><span>are</span><span> important for clinical management. The effective SNP-based CMA detection of wgUPD in CHM may enable physicians to monitor patients at risk for gestational trophoblastic disease and neoplasm.</span><span "=""> </span><span "=""><span>Conventional chromosome analysis of POC has a high </span><span>failure rate, cannot be performed on formalin-fixed paraffin embedded samples, and cannot detect wgUPD. Further</span></span><span "=""> </span><span>multi-institutional collaborative assessmen</span><span> on accuracy, cost-effectiveness, and adequate access to SNP-based CMA, may lead this testing platform to be considered as the first-tier analysis tool for POC specimens, including those showing PHM or CHM. 展开更多
关键词 Complete Hydatidiform Mole (CHM) Gestational Trophoblastic Disease (GTD) Gestational Trophoblastic Neoplasm (GTN) Partial Hydatidiform Mole (PHM) TRIPLOIDY Whole Genome Uniparental Disomy (wgUPD)
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Effects of varying Alx moles on structure and luminescence properties of ZnAl_(x)O_(1.5x+1):0.1 mol%Tb^(3+)nanophosphors prepared using citrate sol-gel method
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作者 V.M.Maphiri L.T.Melato +4 位作者 M.R.Mhlongo T.T.Hlatshwayo T.E.Motaung L.F.Koao S.V.Motloung 《Journal of Rare Earths》 SCIE EI CAS CSCD 2023年第3期358-364,I0002,共8页
Un-doped and ZnAl_(x)O_(1.5x+1):0.1 mol%Tb^(3+)(ZAOT)nano-powders were synthesized via citrate sol-gel method.The AIx moles were varied in the range of 0.25≤x≤5.0.The X-ray powder diffraction(XRD)data reveal that fo... Un-doped and ZnAl_(x)O_(1.5x+1):0.1 mol%Tb^(3+)(ZAOT)nano-powders were synthesized via citrate sol-gel method.The AIx moles were varied in the range of 0.25≤x≤5.0.The X-ray powder diffraction(XRD)data reveal that for x<1.5,the prepared samples crystal structure consists of mixed phases of the cubic ZnAl_(2)O_(4) and hexagonal ZnO phases,while for x>1.5 the structure consists of single phase of cubic ZnAl_(2)O_(4).The Raman and Fourier-trans form infrared(FTIR)vibrational spectroscopy show the presence of vibrations emanating ZnAl_(2)O_(4) spinel.Scanning electron microscopy(SEM)and transmission electron microscopy(TEM)show the presence of irregular sphere at x>2.0 attributed to ZnAl_(2)O_(4).The photoluminescence(PL)spectroscopy reveals emissions from both the host and Tb^(3+)transitions.Emissions from Tb^(3+)are observed at 382,414,439,458 nm and 489,545,585,621 nm,which were attributed to the^(5)D_(3)→^(7)F_(6,5,4,2) and ^(5^)D_(4)→^(7)F_(6,5,4,3),respectively.The results confirm that the Tb^(3+)occupation site depends on the Alx moles.The International Commission on Illumination(CIE)colour chromaticity shows that the emission colour can be tuned from blue to green by varying the AIx moles. 展开更多
关键词 Citrate sol-gel ZnAl_(2)O_(4)/ZnO Tb^(3+)-doped Al_(x)moles Photoluminescence Rare earths
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Plutonium utilization in a small modular molten-salt reactor based on a batch fuel reprocessing scheme
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作者 Xue-Chao Zhao Rui Yan +4 位作者 Gui-Feng Zhu Ya-Fen Liu Jian Guo Xiang-Zhou Cai Yang Zou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期15-28,共14页
A molten salt reactor(MSR)has outstanding features considering the application of thorium fuel,inherent safety,sustainability,and resistance to proliferation.However,fissile material^(233)U is significantly rare at th... A molten salt reactor(MSR)has outstanding features considering the application of thorium fuel,inherent safety,sustainability,and resistance to proliferation.However,fissile material^(233)U is significantly rare at the current stage,thus it is difficult for MSR to achieve a pure thorium-uranium fuel cycle.Therefore,using plutonium or enriched uranium as the initial fuel for MSR is more practical.In this study,we aim to verify the feasibility of a small modular MSR that utilizes plutonium as the starting fuel(SM-MSR-Pu),and highlight its advantages and disadvantages.First,the structural design and fuel management scheme of the SM-MSR-Pu were presented.Second,the neutronic characteristics,such as the graphite-irradiation lifetime,burn-up performance,and coefficient of temperature reactivity were calculated to analyze the physical characteristics of the SM-MSR-Pu.The results indicate that plutonium is a feasible and advantageous starting fuel for a SM-MSR;however,there are certain shortcomings that need to be solved.In a 250 MWth SM-MSR-Pu,approximately 288.64 kg^(233)U of plutonium with a purity of greater than 90% is produced while 978.00 kg is burned every ten years.The temperature reactivity coefficient decreases from -4.0 to -6.5 pcm K^(-1) over the 50-year operating time,which ensures a long-term safe operation.However,the amount of plutonium and accumulation of minor actinides(MAs)would increase as the burn-up time increases,and the annual production and purity of^(233)U will decrease.To achieve an optimal burn-up performance,setting the entire operation time to 30 years is advisable.Regardless,more than 3600 kg of plutonium eventually accumulate in the core.Further research is required to effectively utilize this accumulated plutonium. 展开更多
关键词 Molten salt fuel Plutonium utilization ^(233)U TRUs mole fraction Temperature feedback coefficient
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Complete Hydatidiform Mole at Menopause: A Case Report from Panzi Hospital, Bukavu, Democratic Republic of Congo
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作者 Julien Bwama De-Joseph Kakisingi Mibi +8 位作者 Nsenga Bin Musa Jeff Andrea Mbozi Déborah Kambonesa Salire Dieudonné Kakusu Christine Amisi Tina Aroni Toto Tchass Chasinga Baharanyi Denis Mukwege Mukengere Olivier Nyakio Ngeleza 《Open Journal of Obstetrics and Gynecology》 2024年第7期1010-1017,共8页
Gestational trophoblastic disease is an abnormal proliferation of trophoblastic tissue during pregnancy. It occurs in women of childbearing age, although a few cases have also been observed in post-menopausal women, a... Gestational trophoblastic disease is an abnormal proliferation of trophoblastic tissue during pregnancy. It occurs in women of childbearing age, although a few cases have also been observed in post-menopausal women, although it is extremely rare in the latter. Here we describe a rare case of complete hydatidiform mole in a 56-year-old female patient who presented with genital bleeding combined with nausea and vomiting and a gravid uterus 16 cm in height. The ultrasound findings and the increase in serum β-HCG to 182566.00 mIU/ml suggested a diagnosis of complete hydatidiform mole. Given the post-menopausal state and the future risk of post-molar gestational trophoblastic neoplasia, we opted for total hysterectomy without preservation of the adnexa via a transabdominal approach, followed by antimitotic treatment with methotrexate. The uterus measured 18.45 cm × 11.18 cm with intra cavitary vesicles. Microscopic examination showed chorionic villi of variable size and shape, most of which were dilated and oedematous, associated with trophoblastic cell proliferation and haemorrhage suggestive of complete benign hydatidiform mole. Follow-up showed a consistent decrease in serum β-HCG levels and no evidence of residual disease. A suspicion of gestational trophoblastic disease should be borne in mind when evaluating a patient with peri- or post-menopausal bleeding to avoid delay in diagnosis and treatment. 展开更多
关键词 Complete Hydatidiform Mole MENOPAUSE Β-HCG Panzi Bukavu DRC
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Effect of mole ratio of Y to Zn on phase constituent of Mg-Zn-Zr-Y alloys 被引量:20
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作者 罗素琴 汤爱涛 +2 位作者 潘复生 宋锴 王维青 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第4期795-800,共6页
The phase constituent evolution of Mg-Zn-Y-Zr alloys with the mole ratio of Y to Zn both in the as-cast and as-annealed states at the Mg-rich corner was investigated by XRD and SEM/EDS analysis and was further explain... The phase constituent evolution of Mg-Zn-Y-Zr alloys with the mole ratio of Y to Zn both in the as-cast and as-annealed states at the Mg-rich corner was investigated by XRD and SEM/EDS analysis and was further explained from the ternary phase diagram calculation. The results show that the formation of the secondary phases in Mg-Zn-Y-Zr alloys firmly depends on the mole ratio of Y to Zn, and X (Mg 12 YZn)-phase, W (Mg 3 Y 2 Zn 3 )-phase and I (Mg 3 YZn 6 )-phase come out in sequence as the ratio of Y to Zn decreases. The mole ratios of Y to Zn with the corresponding phase constituent are suggested quantitatively as follows: the phase constituent is α-Mg + I when the mole ratio of Y to Zn is about 0.164; α-Mg + I +W when the mole ratio of Y to Zn is in the range of 0.164 0.33;α-Mg +W when the mole ratio of Y to Zn is about 0.33; α-Mg +W+X when the mole ratio of Y to Zn is in the range of 0.33 1.32; and α-Mg +X when the mole ratio of Y to Zn is about 1.32. The results also offer a guideline for alloy selection and alloy design in Mg-Zn-Y-Zr system. 展开更多
关键词 magnesium alloy Mg-Zn-Zr-Y mole ratio phase constituent
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Microstructure and mechanical properties of Mg,Ag and Zn multi-microalloyed Al-(3.2-3.8)Cu-(1.0-1.4)Li alloys 被引量:13
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作者 李劲风 刘平礼 +2 位作者 陈永来 张绪虎 郑子樵 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第7期2103-2112,共10页
To develop super-high strength Al-Li alloy,the microstructures and mechanical properties of Mg,Ag and Zn microalloyed Al-(3.2-3.8)Cu-(1.0-1.4)Li alloys(mass fraction) with T8 temper were studied.The results show... To develop super-high strength Al-Li alloy,the microstructures and mechanical properties of Mg,Ag and Zn microalloyed Al-(3.2-3.8)Cu-(1.0-1.4)Li alloys(mass fraction) with T8 temper were studied.The results showed that 1%of lower Li content restricted the strengthening effect of increasing Cu content,while simultaneous increase in Cu and Li contents contributed effectively to the enhancement of strength.The alloys were mainly strengthened by plenty of fine and well dispersed TI(Al2CuLi)precipitates.There were also some minor precipitates of θ'(Al2Cu) and δ'(Al3Li),which became less in number density,even disappeared during the aging process.Meanwhile,higher Li content favored the formation θ' and δ' and a small amount of S"(Al2CuMg) phases.In addition,strengthening effect and microstructure variation were analyzed through total non-solution mole fraction of Cu and Li and their mole ratio.To obtain Al-Li alloy with super-high strength,the total mole fractions of Cu and Li should be increased,and their mole ratios should also be kept at a certain high level. 展开更多
关键词 Al-Li alloy PRECIPITATE Cu/Li mole ratio microstructure mechanical properties
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微腔有机发光二极管 被引量:4
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作者 刘明大 石家纬 +4 位作者 李永军 陆羽 杨洪军 缪同群 金恩顺 《半导体光电》 EI CAS CSCD 北大核心 2000年第3期166-168,共3页
设计了由分布布拉格反射镜 (DBR)和金属反射镜面形成的微腔结构。利用 8-羟基喹啉铝 (Alq3)作为电子传输层兼作发光层 ,TPD作为空穴传导层 ,制成了有机发光二极管(OLED)和微腔有机发光二极管 (MOLED)。发现MOLED的光谱半宽比OLED的窄得... 设计了由分布布拉格反射镜 (DBR)和金属反射镜面形成的微腔结构。利用 8-羟基喹啉铝 (Alq3)作为电子传输层兼作发光层 ,TPD作为空穴传导层 ,制成了有机发光二极管(OLED)和微腔有机发光二极管 (MOLED)。发现MOLED的光谱半宽比OLED的窄得多 ,而光密度则得到了增强。对腔长进行调节 ,MOLED光谱峰出现移动。实验结果与理论计算基本符合。 展开更多
关键词 有机发光二极管 微腔 电致发光 MOLED
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新型MOLEDs的光学性能 被引量:3
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作者 闫玲玲 蔡红新 +2 位作者 赵晓霞 张利伟 李宏建 《发光学报》 EI CAS CSCD 北大核心 2010年第3期337-340,共4页
将负折射率介质层(NRIDL)引入到微腔有机电致发光器件(MOLEDs)中,设计了新型的微腔器件。利用传输矩阵法对此器件的反射率大小、器件厚度对发射峰的影响以及电致发光(EL)光谱性质进行了分析和讨论。结果表明:与普通微腔器件相比,新型微... 将负折射率介质层(NRIDL)引入到微腔有机电致发光器件(MOLEDs)中,设计了新型的微腔器件。利用传输矩阵法对此器件的反射率大小、器件厚度对发射峰的影响以及电致发光(EL)光谱性质进行了分析和讨论。结果表明:与普通微腔器件相比,新型微腔器件的谱线宽度显著窄化,峰值强度明显增强,并且受腔体长度的影响较小。这些结果为进一步提高微腔器件的发光色纯度、薄化器件厚度提供了新方法。 展开更多
关键词 负折射率介质层 EL谱 传输矩阵法 MOLEDs
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微腔有机发光器件的设计 被引量:2
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作者 陈吉欣 冉启钧 +2 位作者 林祖伦 黄再生 陈文彬 《液晶与显示》 CAS CSCD 2003年第5期348-350,共3页
介绍了微腔有机发光器件(MOLED)的设计思想、方法和结果。该器件由Alq3作为电子传输层和发光层,TPD作为空穴传输层,ITO作为空穴注入电极,两侧分别分布布喇格反射镜(DBR)和由Al电极形成的金属反射镜。理论设计结果表明,MOLED的峰值光强增... 介绍了微腔有机发光器件(MOLED)的设计思想、方法和结果。该器件由Alq3作为电子传输层和发光层,TPD作为空穴传输层,ITO作为空穴注入电极,两侧分别分布布喇格反射镜(DBR)和由Al电极形成的金属反射镜。理论设计结果表明,MOLED的峰值光强增强19倍,谱线半宽度从100nm变窄到10nm左右。 展开更多
关键词 微腔有机发光器件 设计 MOLED 布喇格反射镜 金属反射镜
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Effect of Zn and Ti mole ratio on microstructure and photocatalytic properties of magnetron sputtered TiO_2-ZnO heterogeneous composite film 被引量:2
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作者 白力静 寇钢 +1 位作者 龚振瑶 赵志明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第12期3643-3649,共7页
Series of TiO 2-ZnO heterojunction composite films with different n(Zn)/n(Ti) ratios were prepared by UDP450 magnetron sputter ion plating equipment, and the mole ratio of Zn to Ti was controlled by adjusting the ... Series of TiO 2-ZnO heterojunction composite films with different n(Zn)/n(Ti) ratios were prepared by UDP450 magnetron sputter ion plating equipment, and the mole ratio of Zn to Ti was controlled by adjusting the current values of sputtering target. The effects of n(Zn)/n(Ti) on the microstructures of TiO2-ZnO films were investigated by SEM, AFM, Raman and XPS, and their photocatalytic decomposition of methyl orange solutions was evaluated. The results show that an increase in n(Zn)/n(Ti) typically results in a decrease in the grain size of composite films firstly and then an increase of grain size, while an increase in n(Zn)/n(Ti) leads to an increase in film roughness firstly and then a decrease in film roughness. Both grain size and roughness of TiO2-ZnO films reach the maximum and minimum at n(Zn)/n(Ti) of 1/9.3, respectively. The n(Zn)/n(Ti) shows little effect on the valences of Zn and Ti elements, which mainly exist in the form of TiO2 and ZnO phases. The n(Zn)/n(Ti) has influence on the amount of anatase/rutile TiO2 heterojunction in the film. With increase of the n(Zn)/n(Ti), the absorption intensity of the composite film increases and the absorption region extends to 450 nm, which is redshifted as much as 150 nm in comparison with the pure TiO2 films. However, the photocatalytic abilities of heterogeneous composite films do not depend on the n(Zn)/n(Ti) but rather on the microstructures of the TiO2-ZnO composite films. Degradation rate of the film reaches the maximum and the photocatalytic decomposition of pollutants works best when n(Zn)/n(Ti)=1:9.3. 展开更多
关键词 magnetron sputtering TiO2-ZnO thin films Zn to Ti mole ratio MICROSTRUCTURE PHOTOCATALYTIC
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曲线顶管技术及顶进力分析计算 被引量:29
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作者 马保松 张雅春 《岩土工程技术》 2006年第5期229-232,259,共5页
曲线顶管施工技术以其特有的优势和应用领域,越来越受到重视。总结了国际上常用的曲线顶管施工技术,分别以SS MOLE和Ultimate Method两种具有代表性的工法为例介绍了曲线顶管技术的地层适应性、适用管道直径、应用领域和所能达到的最小... 曲线顶管施工技术以其特有的优势和应用领域,越来越受到重视。总结了国际上常用的曲线顶管施工技术,分别以SS MOLE和Ultimate Method两种具有代表性的工法为例介绍了曲线顶管技术的地层适应性、适用管道直径、应用领域和所能达到的最小曲率半径。对曲线顶管施工中顶进力计算这一重点和难点,给出了曲线顶管顶推力计算公式,并举例说明了曲线段顶推力计算公式的实际应用。 展开更多
关键词 曲线顶管 顶进力 计算 SS MOLE ULTIMATE METHOD
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含负折射率介质的MOLEDs传输性能研究 被引量:1
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作者 闫玲玲 蔡红新 +1 位作者 赵晓霞 李宏建 《河南理工大学学报(自然科学版)》 CAS 北大核心 2014年第1期117-120,共4页
将由正负折射率介质组成的新型分布布拉格反射镜(DBR)引入到微腔有机电致发光器件(MOLEDs)中,利用传输矩阵法对DBR反射率大小、反射率角度特性和新型微腔器件的透射率、谐振波长及电致发光光谱(EL谱)角度特性进行了分析和讨论.结果表明... 将由正负折射率介质组成的新型分布布拉格反射镜(DBR)引入到微腔有机电致发光器件(MOLEDs)中,利用传输矩阵法对DBR反射率大小、反射率角度特性和新型微腔器件的透射率、谐振波长及电致发光光谱(EL谱)角度特性进行了分析和讨论.结果表明,新型DBR具有宽的反射带宽,且TE波和TM波的反射带宽分离很小.与普通的均由正折射率介质构成的MOLEDs相比,新型MOLEDs的反射率角度特性和透射率、EL谱角度特性均优于普通微腔器件,易于实现全角度反射. 展开更多
关键词 MOLEDs 传输矩阵法 负折射率介质 EL谱
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可视化的Mole
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作者 谢建华 曾小平 孙永强 《计算机工程》 CAS CSCD 北大核心 1999年第5期11-12,30,共3页
移动代理是为解决网络低带宽、高延迟而提出的一种新的分布式计算模型,而Mole是Stuttgart大学开发的一个移动代理系统。Mole实现了一个移动代理系统的基本功能,但它过于简单的字符界面给系统使用带来许多限制和不便... 移动代理是为解决网络低带宽、高延迟而提出的一种新的分布式计算模型,而Mole是Stuttgart大学开发的一个移动代理系统。Mole实现了一个移动代理系统的基本功能,但它过于简单的字符界面给系统使用带来许多限制和不便。在分析这些不足的基础上,设计并实现了Mole的可视化,同时增强了系统的控制功能。 展开更多
关键词 移动代理 Mole系统 可视化 INTERNET网
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国际单位制基本单位之一:摩尔(mole)——现代计量科学专题之八
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作者 李云巧 《物理通报》 2002年第4期1-4,共4页
摩尔是SI基本单位之一,摩尔对化学和物理计量很重要.摩尔的采纳使化学有了基本单位,从而结束了无量纲的历史。通过阿伏伽德罗常量、摩尔质量等,实现了化学各量之间的换算,同时有可能重新定义质量单位——千克。国际计量界已全面合作,致... 摩尔是SI基本单位之一,摩尔对化学和物理计量很重要.摩尔的采纳使化学有了基本单位,从而结束了无量纲的历史。通过阿伏伽德罗常量、摩尔质量等,实现了化学各量之间的换算,同时有可能重新定义质量单位——千克。国际计量界已全面合作,致力于不断提高测量阿伏伽德罗常量的准确度,并已经取得一定成就。当前准确测量阿伏伽德罗常量的技术关键主要是制备高纯的、完美无缺的、超高圆度的单晶硅球;准确测量其直径、圆度、密度、原子量、晶格常量、空穴等。 展开更多
关键词 国际单位制 基本单位 摩尔 MOLE 阿伏伽德罗常量 单晶硅 计量科学
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Kinematics of Terrestrial Locomotion in Mole Cricket Gryllotalpa orientalis 被引量:10
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作者 Yan Zhang He Huang +1 位作者 Xiangyang Liu Luquan Ren 《Journal of Bionic Engineering》 SCIE EI CSCD 2011年第2期151-157,共7页
The fore leg of mole cricket (Orthoptera: Glyllotalpidae) has developed into claw for digging and excavating. As the result of having a well-suited body and appendages for living underground, mole cricket still nee... The fore leg of mole cricket (Orthoptera: Glyllotalpidae) has developed into claw for digging and excavating. As the result of having a well-suited body and appendages for living underground, mole cricket still needs to manoeuvre on land in some cases with some kinds of gait. In this paper, the three-dimensional kinematics information of mole cricket in terrestrial walking was recorded by using a high speed 3D video recording system. The mode and the gait of the terrestrial walking mole cricket were investigated by analyzing the kinematics parameters, and the kinematics coupling disciplines of each limb and body were discussed. The results show that the locomotion gait of mole cricket in terrestrial walking belongs to a distinctive alternating tripod gait. We also found that the fore legs of a mole cricket are not as effective as that of common hexapod insects, its middle legs and body joints act more effective in walking and turning which compensate the function of fore legs. The terrestrial lo-comotion of mole cricket is the result of biological coupling of three pairs of legs, the distinctive alternating tripod gait and the trunk locomotion. 展开更多
关键词 experimental biology mole cricket KINEMATICS terrestrial locomotion biological coupling
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Challenges in the diagnosis and treatment of gestational trophoblastic neoplasia worldwide 被引量:15
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作者 Antonio Braga Paulo Mora +4 位作者 Andréia Cristina de Melo Angélica Nogueira-Rodrigues Joffre Amim-Junior Jorge Rezende-Filho Michael J Seckl 《World Journal of Clinical Oncology》 CAS 2019年第2期28-37,共10页
Gestational trophoblastic neoplasia(GTN) is a rare tumor that originates from pregnancy that includes invasive mole, choriocarcinoma(CCA), placental site trophoblastic tumor and epithelioid trophoblastic tumor(PSTT/ET... Gestational trophoblastic neoplasia(GTN) is a rare tumor that originates from pregnancy that includes invasive mole, choriocarcinoma(CCA), placental site trophoblastic tumor and epithelioid trophoblastic tumor(PSTT/ETT). GTN presents different degrees of proliferation, invasion and dissemination, but, if treated in reference centers, has high cure rates, even in multi-metastatic cases.The diagnosis of GTN following a hydatidiform molar pregnancy is made according to the International Federation of Gynecology and Obstetrics(FIGO)2000 criteria: four or more plateaued human chorionic gonadotropin(hCG)concentrations over three weeks; rise in hCG for three consecutive weekly measurements over at least a period of 2 weeks or more; and an elevated but falling hCG concentrations six or more months after molar evacuation. However,the latter reason for treatment is no longer used by many centers. In addition,GTN is diagnosed with a pathological diagnosis of CCA or PSTT/ETT. For staging after a molar pregnancy, FIGO recommends pelvic-transvaginal Doppler ultrasound and chest X-ray. In cases of pulmonary metastases with more than 1cm, the screening should be complemented with chest computed tomography and brain magnetic resonance image. Single agent chemotherapy, usually Methotrexate(MTX) or Actinomycin-D(Act-D), can cure about 70% of patients with FIGO/World Health Organization(WHO) prognosis risk score ≤ 6(low risk), reserving multiple agent chemotherapy, such as EMA/CO(Etoposide,MTX, Act-D, Cyclophosphamide and Oncovin) for cases with FIGO/WHO prognosis risk score ≥ 7(high risk) that is often metastatic. Best overall cure rates for low and high risk disease is close to 100% and > 95%, respectively. The management of PSTT/ETT differs and cure rates tend to be a bit lower. The early diagnosis of this disease and the appropriate treatment avoid maternal death,allow the healing and maintenance of the reproductive potential of these women. 展开更多
关键词 Gestational trophoblastic neoplasia Chemotherapy Chorionic GONADOTROPIN Invasive MOLE CHORIOCARCINOMA PLACENTAL site trophoblastic TUMOR EPITHELIOID trophoblastic TUMOR
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Character of the Si and Al Phases in Coal Gangue and Its Ash 被引量:6
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作者 WANG Lihua ZHAO Pengda LI Geng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第6期1116-1121,共6页
Analysis of the Si and AI phases in coal gangue fuel and its ash is important for use of coal gangue ashes. A comprehensive study by theoretical and experimental analyses with differential thermal analysis, X-ray diff... Analysis of the Si and AI phases in coal gangue fuel and its ash is important for use of coal gangue ashes. A comprehensive study by theoretical and experimental analyses with differential thermal analysis, X-ray diffraction and Infrared Spectroscopy has been made in the present article to explore the diagram of the Si and Al phases in coal gangue fuel and its ashes. It is found that kaolinite and quartz are the main phases in coal gangue fuel. The ratio of moles A1203 to SiO2 (i.e., Al2O3 (mole) / SiO2 (mole)) is usually no more than 0.5 in most coal gangue fuel and its ashes. The kaolinit at about 984℃ releases a large quantity of SiO2, which makes calcine coal gangue more active than coal gangue itself. The relationship between the ratio A1203 (mole)]SiO2(mole)and the components of coal gangue ash is analyzed, resulting in a formula to calculate the quantity of each phase. Applying the formula to the testing samples from an electric plant in north China supports the above conclusions. 展开更多
关键词 Si and AI phases Al2O3 (mole)/SiO2(mole) coal gangue fuel coal gangue ash
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Design Guideline of Ultra Thin Body MOSFET
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作者 王文平 黄如 张国艳 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第10期1227-1232,共6页
Simulation method is used to provide a guideline f or ultra thin body(UTB) MOSFET designs.Three important parameters of the UTB MOS FE T,i.e.the raised S/D height,Ge mole fraction of the Ge xSi 1-x gate,and the ... Simulation method is used to provide a guideline f or ultra thin body(UTB) MOSFET designs.Three important parameters of the UTB MOS FE T,i.e.the raised S/D height,Ge mole fraction of the Ge xSi 1-x gate,and the silic on body thickness,are comprehensively analyzed and optimized.The optimal region of feasible Ge mole fraction and the silicon body thickness for low operating po wer device are given.As the simulation results show that through changing Ge mole fraction coupl ed with the silicon body thickness tuning,UTB device with good performance can b e obtained. 展开更多
关键词 ultra thin body MOSFET raised S/D height Ge mole fraction silicon body thicknessEEACC:4250 128 0
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Oxidative dehydrogenation of propane over Ni-Mo-Mg-O catalysts 被引量:5
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作者 Lin Wang Wei Chu +3 位作者 Chengfa Jiang Yuefeng Liu Jie Wen Zaiku Xie 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第1期43-48,共6页
In this work, a series of Ni-Mo-Mg-O catalysts with mesoporous structure prepared by sol-gel method were investigated for the oxidative dehydrogenation of propane (ODHP). The techniques of temperature-programmed red... In this work, a series of Ni-Mo-Mg-O catalysts with mesoporous structure prepared by sol-gel method were investigated for the oxidative dehydrogenation of propane (ODHP). The techniques of temperature-programmed reduction with H2 (H2-TPR), N2 adsorption-desolption, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and X-ray photoelectron spectra (XPS) were employed for catalyst characterization. It is found that the activity of the catalysts for ODHP increases first and then decreases with the increase of Mo content. The catalyst with a Mo/Ni atomic ratio of 1/1 exhibits the best catalytic activity, which gives the propene selectivity of 81.4% at a propane conversion of 11.3% under 600 ~C and maintains the good catalytic performance for 22 h on stream. This is related not only to its high reducibility and dispersion as revealed by TPR and XRD, but also to the formation of more selective oxygen species on the MoOz-NiO interface as identified by XPS. 展开更多
关键词 nickel oxide molybdenum oxide mole ratio oxidative dehydrogenation of propane PROPENE
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