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起爆网路 2

高架桥 2

分部延时起爆 1

可持续发展战略 1

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电子雷管；起爆技术；延期参数；设计理论；标准体系 1

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城市高架桥爆破拆除起爆网路可靠性研究

吴新霞,赵根,谢先启

《中国工程科学》 2014年第16卷第11期页码 72-77

摘要：

本文针对城市高架桥爆破拆除的长距离、长延时，目前只能采用非电起爆网路进行起爆的现状，研究了多发并联起爆网路的接力点雷管延期特性，提出了并联后的接力点起爆时间期望值的简易计算公式。针对不同规模的非电起爆网路提出了相应的可靠度标准，研发了既可保证高架桥倾倒过程不发生侧翻又能提高接力点起爆可靠度并可无限分段的复式交叉接力起爆网路，并推导了其起爆可靠度计算公式。相关成果为高架桥拆除爆破起爆网路设计提供了科学依据。

关键词：高架桥拆除爆破起爆网路可靠性

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hepatocellular carcinoma progression by repressing translation through the interaction with eukaryotic initiation

《医学前沿（英文）》 2023年第17卷第3期页码 476-492 doi: 10.1007/s11684-022-0966-6

摘要： tRNA-derived small RNAs (tsRNAs) are novel non-coding RNAs that are involved in the occurrence and progression of diverse diseases. However, their exact presence and function in hepatocellular carcinoma (HCC) remain unclear. Here, differentially expressed tsRNAs in HCC were profiled. A novel tsRNA, tRNA^Gln-TTG derived 5′-tiRNA-Gln, is significantly downregulated, and its expression level is correlated with progression in patients. In HCC cells, 5′-tiRNA-Gln overexpression impaired the proliferation, migration, and invasion in vitro and in vivo, while 5′-tiRNA-Gln knockdown yielded opposite results. 5′-tiRNA-Gln exerted its function by binding eukaryotic initiation factor 4A-I (EIF4A1), which unwinds complex RNA secondary structures during translation initiation, causing the partial inhibition of translation. The suppressed downregulated proteins include ARAF, MEK1/2 and STAT3, causing the impaired signaling pathway related to HCC progression. Furthermore, based on the construction of a mutant 5′-tiRNA-Gln, the sequence of forming intramolecular G-quadruplex structure is crucial for 5′-tiRNA-Gln to strongly bind EIF4A1 and repress translation. Clinically, 5′-tiRNA-Gln expression level is negatively correlated with ARAF, MEK1/2, and STAT3 in HCC tissues. Collectively, these findings reveal that 5′-tiRNA-Gln interacts with EIF4A1 to reduce related mRNA binding through the intramolecular G-quadruplex structure, and this process partially inhibits translation and HCC progression.

关键词： EIF4A1 G-quadruplex hepatocellular carcinoma tRNA-derived small RNA translation initiation

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Liquid metal material genome: Initiation of a new research track towards discovery of advanced energy

Lei WANG, Jing LIU

《能源前沿（英文）》 2013年第7卷第3期页码 317-332 doi: 10.1007/s11708-013-0271-9

摘要： As the basis of modern industry, the roles materials play are becoming increasingly vital in this day and age. With many superior physical properties over conventional fluids, the low melting point liquid metal material, especially room-temperature liquid metal, is recently found to be uniquely useful in a wide variety of emerging areas from energy, electronics to medical sciences. However, with the coming enormous utilization of such materials, serious issues also arise which urgently need to be addressed. A biggest concern to impede the large scale application of room-temperature liquid metal technologies is that there is currently a strong shortage of the materials and species available to meet the tough requirements such as cost, melting point, electrical and thermal conductivity, etc. Inspired by the Material Genome Initiative as issued in 2011 by the United States of America, a more specific and focused project initiative was proposed in this paper—the liquid metal material genome aimed to discover advanced new functional alloys with low melting point so as to fulfill various increasing needs. The basic schemes and road map for this new research program, which is expected to have a worldwide significance, were outlined. The theoretical strategies and experimental methods in the research and development of liquid metal material genome were introduced. Particularly, the calculation of phase diagram (CALPHAD) approach as a highly effective way for material design was discussed. Further, the first-principles (FP) calculation was suggested to combine with the statistical thermodynamics to calculate the thermodynamic functions so as to enrich the CALPHAD database of liquid metals. When the experimental data are too scarce to perform a regular treatment, the combination of FP calculation, cluster variation method (CVM) or molecular dynamics (MD), and CALPHAD, referred to as the mixed FP-CVM-CALPHAD method can be a promising way to solve the problem. Except for the theoretical strategies, several parallel processing experimental methods were also analyzed, which can help improve the efficiency of finding new liquid metal materials and reducing the cost. The liquid metal material genome proposal as initiated in this paper will accelerate the process of finding and utilization of new functional materials.

关键词： liquid metal material genome energy material material discovery advanced material room-temperature liquid alloy thermodynamics phase diagram

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Breast cancer-associated fibroblasts: their roles in tumor initiation, progression and clinical applications

null

《医学前沿（英文）》 2016年第10卷第1期页码 33-40 doi: 10.1007/s11684-016-0431-5

摘要：

Breast cancer is the most common malignant tumor in women, and the incidence of this disease has increased in recent years because of changes in diet, living environment, gestational age, and other unknown factors. Previous studies focused on cancer cells, but an increasing number of recent studies have analyzed the contribution of cancer microenvironment to the initiation and progression of breast cancer. Cancer-associated fibroblasts (CAFs), the most abundant cells in tumor stroma, secrete various active biomolecules, including extracellular matrix components, growth factors, cytokines, proteases, and hormones. CAFs not only facilitate the initiation, growth, angiogenesis, invasion, and metastasis of cancer but also serve as biomarkers in the clinical diagnosis, therapy, and prognosis of breast cancer. In this article, we reviewed the literature and summarized the research findings on CAFs in breast cancer.

关键词： cancer-associated fibroblast breast cancer progression prognosis

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Fatigue crack initiation of magnesium alloys under elastic stress amplitudes: A review

B. J. WANG, D. K. XU, S. D. WANG, E. H. HAN

《机械工程前沿（英文）》 2019年第14卷第1期页码 113-127 doi: 10.1007/s11465-018-0482-1

摘要： The most advantageous property of magnesium (Mg) alloys is their density, which is lower compared with traditional metallic materials. Mg alloys, considered the lightest metallic structural material among others, have great potential for applications as secondary load components in the transportation and aerospace industries. The fatigue evaluation of Mg alloys under elastic stress amplitudes is very important in ensuring their service safety and reliability. Given their hexagonal close packed structure, the fatigue crack initiation of Mg and its alloys is closely related to the deformation mechanisms of twinning and basal slips. However, for Mg alloys with shrinkage porosities and inclusions, fatigue cracks will preferentially initiate at these defects, remarkably reducing the fatigue lifetime. In this paper, some fundamental aspects about the fatigue crack initiation mechanisms of Mg alloys are reviewed, including the 3 followings: 1) Fatigue crack initiation of as-cast Mg alloys, 2) influence of microstructure on fatigue crack initiation of wrought Mg alloys, and 3) the effect of heat treatment on fatigue initiation mechanisms. Moreover, some unresolved issues and future target on the fatigue crack initiation mechanism of Mg alloys are also described.

关键词： Mg alloys fatigue behavior microstructure crack initiation deformation mechanism

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regulators endow hematopoietic stem cells with the preleukemic stem cell property, a requisite of leukemia initiation

null

《医学前沿（英文）》 2015年第9卷第4期页码 412-420 doi: 10.1007/s11684-015-0423-x

摘要：

Genetic mutations are considered to drive the development of acute myeloid leukemia (AML). With the rapid progress in sequencing technologies, many newly reported genes that are recurrently mutated in AML have been found to govern the initiation and relapse of AML. These findings suggest the need to distinguish the driver mutations, especially the most primitive single mutation, from the subsequent passenger mutations. Recent research on DNA methyltransferase 3A (DNMT3A) mutations provides the first proof-of-principle investigation on the identification of preleukemic stem cells (pre-LSCs) in AML patients. Although DNMT3A mutations alone may only transform hematopoietic stem cells into pre-LSCs without causing the full-blown leukemia, the function of this driver mutation appear to persist from AML initiation up to relapse. Therefore, identifying and targeting preleukemic mutations, such as DNMT3A mutations, in AML is a promising strategy for treatment and reduction of relapse risk.

关键词： preleukemic stem cell acute myeloid leukemia relapse DNMT3A

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Hierarchical approach for fatigue cracking performance evaluation in asphalt pavements

Ibrahim ONIFADE, Yared DINEGDAE, Björn BIRGISSON

《结构与土木工程前沿（英文）》 2017年第11卷第3期页码 257-269 doi: 10.1007/s11709-017-0410-1

摘要： In this paper, a hierarchical approach is proposed for the evaluation of fatigue cracking in asphalt concrete pavements considering three different levels of complexities in the representation of the material behaviour, design parameters characterization and the determination of the pavement response as well as damage computation. Based on the developed hierarchical approach, three damage computation levels are identified and proposed. The levels of fatigue damage analysis provides pavement engineers a variety of tools that can be used for pavement analysis depending on the availability of data, required level of prediction accuracy and computational power at their disposal. The hierarchical approach also provides a systematic approach for the understanding of the fundamental mechanisms of pavement deterioration, the elimination of the empiricism associated with pavement design today and the transition towards the use of sound principles of mechanics in pavement analysis and design.

关键词： fatigue cracking energy based crack initiation mechanistic approach pavement analysis

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Initiation and propagation laws of the glass cracks in specimens subjected to normal loading under the

WAN Zhen-ping, LIU Ya-jun, TANG Yong, YE Bang-yan

《机械工程前沿（英文）》 2006年第1卷第2期页码 194-198 doi: 10.1007/s11465-005-0011-x

摘要： With more and more applications of glass in advanced fields of science, the demand for glass machining precision has increased greatly. More and more attention is being paid to glass cutting because precise glass parts with various shapes can be obtained at high efficiency and low cost. To improve the machining precision of part surfaces and to facilitate tool design and cutting parameter selection, the initiation and propagation laws of glass cracks in specimens subjected to normal loading by symmetric wedges were investigated. Research results show that initiation and propagation laws are the same with interior symmetric wedge angles of 30o-120o, while the laws are different with interior symmetric wedge angles equal to or more than "e150o. The relationship between medial crack length and normal loading was also investigated when specimens were indented by symmetrical wedges with interior angles of 30o-120o.

关键词： different 30o-120o relationship initiation cutting parameter

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Chemotherapy initiation with single-course methotrexate alone or combined with dactinomycin versus multi-course

《医学前沿（英文）》 2022年第16卷第2期页码 276-284 doi: 10.1007/s11684-021-0855-4

摘要： We aimed to evaluate the effectiveness and safety of single-course initial regimens in patients with low-risk gestational trophoblastic neoplasia (GTN). In this trial (NCT01823315), 276 patients were analyzed. Patients were allocated to three initiated regimens: single-course methotrexate (MTX), single-course MTX+ dactinomycin (ACTD), and multi-course MTX (control arm). The primary endpoint was the complete remission (CR) rate by initial drug(s). The primary CR rate was 64.4% with multi-course MTX in the control arm. For the single-course MTX arm, the CR rate was 35.8% by one course; it increased to 59.3% after subsequent multi-course MTX, with non-inferiority to the control (difference –5.1%, 95% confidence interval (CI) –19.4% to 9.2%, P=0.014). After further treatment with multi-course ACTD, the CR rate (93.3%) was similar to that of the control (95.2%, P=0.577). For the single-course MTX+ACTD arm, the CR rate was 46.7% by one course, which increased to 89.1% after subsequent multi-course, with non-inferiority (difference 24.7%, 95% CI 12.8%–36.6%, P<0.001) to the control. It was similar to the CR rate by MTX and further ACTD in the control arm (89.1% vs. 95.2%, P=0.135). Four patients experienced recurrence, with no death, during the 2-year follow-up. We demonstrated that chemotherapy initiation with single-course MTX may be an alternative regimen for patients with low-risk GTN.

关键词： gestational trophoblastic neoplasia (GTN) methotrexate (MTX) dactinomycin (ACTD)

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电子雷管起爆技术研究进展与发展建议

冷振东,范勇,涂书芳,周桂松,郭一鸣

《中国工程科学》 2023年第25卷第1期页码 142-154 doi: 10.15302/J-SSCAE-2023.07.001

摘要：

电子雷管提高了延期精度以及起爆网路设计的灵活性，可实现“生产‒ 运输‒ 储存‒ 使用”全生命周期安全管控，成为民爆行业重点发展方向。本文从产品结构、应用场景、智能化水平、爆破设计理论、拒爆失效机理等方面着手，梳理了电子雷管起爆技术的发展现状，总结了系列化和标准化、智能化、短延时设计、大规模起爆网路等技术发展趋势；结合工程应用实践，凝练了复杂环境下拒爆现象频发、爆破应用研究脱节、产品类型单一、标准体系不健全等电子雷管起爆技术与应用问题。着眼民爆行业发展需求，提出了电子雷管起爆技术的重点研究方向：电子雷管精确延时控制爆破破岩理论，信息技术与电子雷管起爆技术融合，差异化的电子雷管产品体系，电子雷管标准体系。

关键词：电子雷管；起爆技术；延期参数；设计理论；标准体系

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Initiation of Setaria as a model plant

Xianmin DIAO,James SCHNABLE,Jeffrey L. BENNETZEN,Jiayang LI

《农业科学与工程前沿（英文）》 2014年第1卷第1期页码 16-20 doi: 10.15302/J-FASE-2014011

摘要： Model organisms such as Arabidopsis ( ) and rice ( ) have proven essential for efficient scientific discovery and development of new methods. With the diversity of plant lineages, some important processes such as C photosynthesis are not found in either Arabidopsis or rice, so new model species are needed. Due to their small diploid genomes, short life cycles, self-pollination, small adult statures and prolific seed production, domesticated foxtail millet ( ) and its wild ancestor, green foxtail ( ), have recently been proposed as novel model species for functional genomics of the Panicoideae, especially for study of C photosynthesis. This review outlines the development of these species as model organisms, and discusses current challenges and future potential of a Setaria model.

关键词： Setaria foxtail millet C₄ photosynthesis model organism

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地铁隧道爆破施工下穿地表建筑物的减振技术研究

方俊波

《中国工程科学》 2014年第16卷第11期页码 58-64

摘要：

城市地铁区间隧道爆破施工中面临的一个重要问题就是降低爆破振动对临近地表建筑物的影响。青岛地铁一期工程03号线03标段下穿建筑物时，为了确保距隧道拱顶5～8 m的地表建筑物安全，采用了大中空孔直眼掏槽技术、一次起爆分部延时爆破、浅孔多眼等技术，将地表建筑物最大垂直振速控制在国标允许范围之内，隧道通过后地表建筑物完好无损。并在施工中解决了大断面隧道爆破施工导爆管雷管段数不能满足施工要求、分断面施工不能同时实施爆破作业，施工效率低下的问题，既保证了工程施工安全又满足了进度要求。

关键词：爆破设计直眼掏槽大直径中空孔分部延时起爆浅孔爆破

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钱学森创立知识密集型草产业的划时代贡献

李毓堂

《中国工程科学》 2002年第4卷第1期页码 15-22

摘要：

文章论述了钱学森提出创建知识密集型草产业的历史背景、科学内涵、理论意义、应用成果和在21世纪中国可持续发展战略中的重要作用，并根据钱老的主张，提出当前启动全国大规模草产业工程必须创新管理机制。

关键词：钱学森知识密集型草产业草业系统工程可持续发展战略

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Cracking evolution behaviors of lightweight materials based on

Y. Luo, S. C. Wu, Y. N. Hu, Y. N. Fu

《机械工程前沿（英文）》 2018年第13卷第4期页码 461-481 doi: 10.1007/s11465-018-0481-2

摘要：

Damage accumulation and failure behaviors are crucial concerns during the design and service of a critical component, leading researchers and engineers to thoroughly identifying the crack evolution. Third-generation synchrotron radiation X-ray computed microtomography can be used to detect the inner damage evolution of a large-density material or component. This paper provides a brief review of studying the crack initiation and propagation inside lightweight materials with advanced synchrotron three-dimensional (3D) X-ray imaging, such as aluminum materials. Various damage modes under both static and dynamic loading are elucidated for pure aluminum, aluminum alloy matrix, aluminum alloy metal matrix composite, and aluminum alloy welded joint. For aluminum alloy matrix, metallurgical defects (porosity, void, inclusion, precipitate, etc.) or artificial defects (notch, scratch, pit, etc.) strongly affect the crack initiation and propagation. For aluminum alloy metal matrix composites, the fracture occurs either from the particle debonding or voids at the particle/matrix interface, and the void evolution is closely related with fatigued cycles. For the hybrid laser welded aluminum alloy, fatigue cracks usually initiate from gas pores located at the surface or sub-surface and gradually propagate to a quarter ellipse or a typical semi-ellipse profile.

关键词： fatigue crack initiation and growth fatigue damage mechanism damage tolerance defect characterization laser welded aluminum alloys