Physapruin A Enhances DNA Damage and Inhibits DNA Repair to Suppress Oral Cancer Cell Proliferation

The selective antiproliferation to oral cancer cells of Physalis peruviana-derived physapruin A (PHA) is rarely reported. Either drug-induced apoptosis and DNA damage or DNA repair suppression may effectively inhibit cancer cell proliferation. This study examined the selective antiproliferation ability of PHA and explored detailed mechanisms of apoptosis, DNA damage, and repair. During an ATP assay, PHA provided high cytotoxicity to two oral cancer cell lines (CAL 27 and Ca9-22) but no cytotoxicity to two non-malignant oral cells (HGF-1 and SG). This selective antiproliferation of PHA was associated with the selective generation of reactive oxygen species (ROS) in oral cancer cells rather than in non-malignant oral cells, as detected by flow cytometry. Moreover, PHA induced other oxidative stresses in oral cancer cells, such as mitochondrial superoxide generation and mitochondrial membrane potential depletion. PHA also demonstrated selective apoptosis in oral cancer cells rather than non-malignant cells in annexin V/7-aminoactinmycin D and caspase 3/7 activity assays. In flow cytometry and immunofluorescence assays, PHA induced γH2AX expressions and increased the γH2AX foci number of DNA damages in oral cancer cells. In contrast, the mRNA expressions for DNA repair signaling, including homologous recombination (HR) and non-homologous end joining (NHEJ)-associated genes, were inhibited by PHA in oral cancer cells. Moreover, the PHA-induced changes were alleviated by the oxidative stress inhibitor N-acetylcysteine. Therefore, PHA generates selective antiproliferation, oxidative stress, and apoptosis associated with DNA damage induction and DNA repair suppression in oral cancer cells.     

基于SEM的建筑工人疲劳对不安全行为影响机理

为有效约束有限空间作业人员不安全行为,从有限理性角度出发,构建有限空间作业人员和管理人员的演化博弈模型,探究不同奖惩机制下的主体策略演化过程,在此基础上通过数值仿真分析不同参数变化对系统演化轨迹的影响。研究发现,管理人员采取溢出效应奖惩机制时,不存在稳定策略组合,采用动态奖惩机制可以实现演化稳定状态,动态溢出奖惩机制的管理效果优于动态奖惩机制;管理人员和作业人员的安全行为与安全投入成本呈负相关关系,与奖惩上限值和政府惩罚值呈正相关关系。研究结果从降低安全管理投入成本、完善安全管理奖惩机制、加强第三方监管3个方面为有限空间作业安全管理提出了建议与措施。

     

诱导气流对转载点雾化特性影响规律的数值模拟与试验

为了解决疏水性煤尘难润湿、微米级粉尘降尘率较低等难题,选取1-丁基-3-甲基咪唑氯盐([Bmim][Cl])、1-丁基-3-甲基咪唑四氟硼酸盐([Bmim][BF₄])、1-乙基-3-甲基咪唑四氟硼酸盐([Emim][BF₄])3种咪唑类离子液体,开展不同变质程度的煤尘表面润湿特性试验研究,分析不同阳、阴离子数的复配活性水溶液对煤尘润湿性能的影响规律。结果表明,阳离子[Emim]⁺和[Bmim]⁺能有效屏蔽阴离子[BF₄]^-、Cl^-之间的静电相互作用,促进阴离子在气—液界面之间的吸附和聚集,致使表面张力、接触角均随活性水溶液的离子液体质量分数的增大而逐渐降低;咪唑阳离子侧链上的H原子与煤中的—OH、—COOH等基团形成氢键,破坏了煤中原有氢键,提高了离子液体对煤的溶解能力,长焰煤的润湿效果最好,褐煤次之,焦煤最差;复配后的活性水溶液通过破坏煤中官能团增强了对煤结构的溶解能力,降低了水的表面张力并提高溶液的润湿能力,复配溶液实现了协同增润作用,可为开发新型润湿剂提供新的思路和方向。

     

塔河油田底水砂岩油藏水平井剩余油主控因素分析

针对塔河油田一区、九区等强底水砂岩油藏高含水期油水关系复杂、影响因素多、剩余油认识不清造成措施难度大的特点,分析了不同主控因素下水淹模式及剩余油的形成和分布特征。从水平井轨迹与夹层不同的配置关系入手,将轨迹与夹层的配置关系分为全遮挡型、穿行夹层型、穿过夹层型和半遮挡型4种配置关系。根据渗透率组合形态将水平段渗透率组合分为4种形态:两段式、锯齿式、台阶式和均匀式,并结合油井生产动态研究了不同配置关系及渗透率形态所对应的水平段水淹模式,描述其对剩余油不同控制作用,并结合矿场试验给出各种剩余油赋存方式适合的挖潜手段,为底水油藏剩余油精细挖潜提供依据。     

响应面法优化泡椒牦牛黄喉制作工艺研究

对牦牛黄喉进行泡椒产品的开发,有利于牦牛副产物的增值增效,提高产品附加值。本实验以水煮时间、食用碱质量浓度、浸渍液中泡椒的比例和泡制时间4个反应因素,以泡椒牦牛黄喉感官评分为评价指标,在单因素工艺实验的基础上,通过四因素三水平的Box-Behnken响应面分析法优化泡椒牦牛黄喉的制作工艺条件。经方差分析得知泡制时间和食用碱质量浓度的交互影响显著,泡椒比例和泡制时间对泡椒牦牛黄喉的交互影响极显著。结果表明,最优制作条件为水煮时间25min,食用碱质量浓度0.7g/100m L,泡椒比例21%,泡制时间53h。在此制作条件下得到泡椒牦牛黄喉色泽良好,口感细腻,脆嫩,泡椒香气浓郁,泡椒牦牛黄喉感官评分可达到36.19。验证实验泡椒牦牛黄喉感官评分为35.27,表明实验结果与软件优化结果相符。      

Assembly of the Complete Mitochondrial Genome of Gelsemium elegans Revealed the Existence of Homologous Conformations Generated by a Repeat Mediated Recombination

Gelsemium elegans (G. elegans) is a Chinese medicinal plant with substantial economic and feeding values. There is a lack of detailed studies on the mitochondrial genome of G. elegans. In this study, the mitochondrial genome of G. elegans was sequenced and assembled, and its substructure was investigated. The mitochondrial genome of G. elegans is represented by two circular chromosomes of 406,009 bp in length with 33 annotated protein-coding genes, 15 tRNA genes, and three rRNA genes. We detected 145 pairs of repeats and found that four pairs of repeats could mediate the homologous recombination into one major conformation and five minor conformations, and the presence of conformations was verified by PCR amplification and Sanger sequencing. A total of 124 SSRs were identified in the G. elegans mitochondrial genome. The homologous segments between the chloroplast and mitochondrial genomes accounted for 5.85% of the mitochondrial genome. We also predicted 477 RNA potential editing sites and found that the nad4 gene was edited 38 times, which was the most frequent occurrence. Taken together, the mitochondrial genome of G. elegans was assembled and annotated. We gained a more comprehensive understanding on the genome of this medicinal plant, which is vital for its effective utilization and genetic improvement, especially for cytoplasmic male sterility breeding and evolution analysis in G. elegans.     

Isocitrate Dehydrogenase Alpha-1 Modulates Lifespan and Oxidative Stress Tolerance in Caenorhabditis elegans

Altered metabolism is a hallmark of aging. The tricarboxylic acid cycle (TCA cycle) is an essential metabolic pathway and plays an important role in lifespan regulation. Supplementation of α-ketoglutarate, a metabolite converted by isocitrate dehydrogenase alpha-1 (idha-1) in the TCA cycle, increases lifespan in C. elegans. However, whether idha-1 can regulate lifespan in C. elegans remains unknown. Here, we reported that the expression of idha-1 modulates lifespan and oxidative stress tolerance in C. elegans. Transgenic overexpression of idha-1 extends lifespan, increases the levels of NADPH/NADP⁺ ratio, and elevates the tolerance to oxidative stress. Conversely, RNAi knockdown of idha-1 exhibits the opposite effects. In addition, the longevity of eat-2 (ad1116) mutant via dietary restriction (DR) was reduced by idha-1 knockdown, indicating that idha-1 may play a role in DR-mediated longevity. Furthermore, idha-1 mediated lifespan may depend on the target of rapamycin (TOR) signaling. Moreover, the phosphorylation levels of S6 kinase (p-S6K) inversely correlate with idha-1 expression, supporting that the idha-1-mediated lifespan regulation may involve the TOR signaling pathway. Together, our data provide new insights into the understanding of idha-1 new function in lifespan regulation probably via DR and TOR signaling and in oxidative stress tolerance in C. elegans.     

高层建筑抗风优化设计和风振控制相关问题研究

黏弹性材料在消声降噪、精密仪器减振和建筑结构防震减灾等领域存在较多应用。炭黑、白炭黑等填料体系是黏弹性材料的重要组成部分。该文采用随机序列吸附方法,建立了不同体积炭黑填充黏弹性材料的代表体积单元(RVE)模型,基于有效体积分数对有限元模型进行修正,从细观尺度对不同体积分数炭黑填充黏弹性材料的弹性力学行为和动态耗能指标进行了计算分析,与经验值和试验结果进行了对比验证。结果表明：采用有效体积分数建模时,RVE方法计算得到不同体积分数下炭黑填充黏弹性材料的应力-应变曲线、动态耗能指标均能与试验和理论结果较好吻合。

     

BIM技术在深基坑支护预应力锚索施工中的应用

利用BIM技术,建立了湖南广电节目生产基地项目深基坑支护桩锚三维信息模型,实现了预应力锚索的预建造,辅助工程师提前发现了图纸中存在的问题,并采取相应措施进行了处理。通过BIM技术的应用,重点发现并解决了原设计图纸中预应力锚索的碰撞问题,将碰撞报告提交设计院进行了图纸优化设计,并制作了三维可视化交底动画,为项目深基坑支护工程按期、保质完成提供了强有力的技术支持,取得了良好的经济效益与社会效益。     

米团花花中挥发性成分的GC-MS分析

为了比较不同提取方法和不同试剂对米团花花中的挥发性成分的化学组成,采取水蒸气蒸馏法和超声波法对干米团花的挥发性成分进行提取,并采用GC-MS方法对提取的挥发性成分进行鉴定。结果是不同的方法和不同的试剂提取得到的成分和含量有一定的差异。水蒸气蒸馏法得到了4种挥发性成分,主要是酯类;利用超声波法提取时,乙醚萃取得到11种,二氯甲烷萃取得到21种,石油醚萃取得到15种,主要是烷类。