2,070 research outputs found

    Sedimentary record of anchovy population dynamics in the Yellow Sea and its response to climate changes

    Get PDF
    以往的鱼类种群动态研究和管理措施,多数采用了被研究鱼类捕捞产量取代资源量的方法,两者之间不仅存在着巨大差异,而且时间尺度较短,种群自然波动、人为干预和全球气候变化引起的鱼类资源变化相互交织,难以理清引起鱼类种群变化的主导因素。日本鳀(Engraulisjaponicus)是黄、东海单品种现存量最高的鱼种,以摄食浮游动物为主,同时也是高营养级动物食性鱼类的重要饵料生物,在食物网浮游动物与高营养级鱼类的能量和营养转化中起着承上启下的重要作用,是黄、东海生态系统能量和营养动力学研究的关键种。鳀鱼作为黄海陆架资源量最大、最有代表性的小型中上层鱼类,因资源生态学连续调查资料的严重短缺,且在时间尺度上与资...Previous works concerning fish population dynamics and management are mainly based on short historical catch records, rather than standing stock. Historical catch alone is acknowledged to be a crude measure of standing stock as there always exists large errors between catches and standing stocks. Meanwhile, such catches data has only short time-scale and are significantly impacted by both natural ...学位:理学博士院系专业:海洋与地球学院_海洋生物学学号:2232012015345

    A study on the construction of Comprehensive performance management system for Private Colleges Teachers--Take Fuzhou College of Foreign Studies and Trade as An Example

    Get PDF
    摘要 高校教师作为高等院校发展的重要资源,在人才培养、学科建设、科研成果转化和产出等方面都起着决定性作用。如何针对高校教师绩效进行管理,提升高校教师的工作积极性,增强教师对学校的认同感和归属感,进而最大限度地发挥他们的潜力,为学校日后的发展做出更大贡献,已引起高校管理者的广泛重视。自1992年以来,我国民办高校异军突起,成为高等教育系统的重要组成部分,经过多年的发展,在“量”和“质”上都有所突破,日益被广大的社会公众所认可。然而,因为政策和环境的原因,民办高校在发展的过程中,也面临着许多不可避免的现实问题,其中首要问题就是民办高校师资队伍的建设和管理,这是影响一所民办高校是否可持续发展的核心...Abstract The faculty is an important resource in a college’s development for personnel training and discipline construction. It plays a major role in transfer and yield of research achievements. The managers of colleges already focus on how to supervise the performances about the staffs for reaching their full potentialities to make more contributions in colleges’ developments. The key factor of ...学位:工商管理硕士院系专业:管理学院_工商管理硕士(高级管理人员工商管理硕士)学号:X201215623

    The mechanism of Honokiol induced cancer cell apoptosis via AMPK/Nur77 signal pathway

    Get PDF
    AMPK是高度保守的细胞内能量感应器,它能通过抑制细胞增殖和生物合成过程响应细胞内能量应激。越来越多的研究表明,AMPK不仅是细胞能量平衡和代谢途径的主要调节因子,还与细胞凋亡和细胞自噬等过程有关。Nur77(也称为TR3/NGFI-B)是由立早基因NR4A1编码的孤儿核受体,是核受体超家族中的一员。Nur77能被激素、生长因子等诱导表达,参与细胞的生长、发育、增殖和凋亡等重要生理过程。 和厚朴酚是传统中药厚朴或凹叶厚朴中的主要活性成分之一。研究表明,和厚朴酚具有抗菌、抗炎、抗氧化、抗焦虑、抗血管生成和抗肿瘤等重要生理功能。和厚朴酚能够抑制多种肿瘤细胞生长,诱导细胞凋亡,和厚朴酚还能诱导肿瘤...AMPK is a highly conserved sensor of cellular energy status which can in response to energy stress by suppression of proliferation and biosynthesis of cancer cell. Research increasingly suggests that AMPK is not only a main regulator of cellular energy homeostasis and metabolic pathways, it’s also associated with apoptosis and autophagy of cancer cell. Nur77 is an orphan receptor coded by immediat...学位:理学硕士院系专业:药学院_化学生物学学号:3232013115338

    Chemical exchange saturation transfer imaging and reconstruction method for water-fat separated imaging based on single-shot spatiotemporal encoding

    Get PDF
    超快速成像是磁共振成像(magneticresonanceimaging,MRI)领域的研究热点之一,其良好的时间分辨率不仅能够提高磁共振成像的工作效率和减轻运动伪影,而且促使了许多动态成像技术的产生。平面回波成像(echoplanarimaging,EPI)作为一种应用广泛的超快速成像技术,在时间和空间分辨率方面都有出色的表现。然而在高场条件下,EPI图像很容易受到不均匀场和化学位移效应的影响而产生伪影和畸变。由Frydman小组提出的单扫描时空编码磁共振成像(spatiotemporallyencodedMRI,SPENMRI)技术不仅保留了EPI在时间分辨率方面的优势,而且具有较强的抵抗...Ultrafast imaging is one of the hotspots in the field of magnetic resonance imaging (MRI), whose good temporal resolution can not only improve the working efficiency of magnetic resonance imaging and reduce the motion artifacts, but also promote the emergence of many dynamic imaging techniques. As a widely used ultrafast imaging technique, planar echo imaging (EPI) has excellent performance in bot...学位:理学硕士院系专业:物理科学与技术学院_无线电物理学号:3332014115281

    小扭口藓(Barbula indica)芽胞发育特征的实验研究

    Get PDF
    在光照培养箱中人工对照培养小扭口藓(Barbulaindica(Hook. )Spreng)的芽胞,显微镜下观察并记录其发育成配子体的全过程。结果表明:小扭口藓芽胞在3 ~4d即可萌发; 10d左右开始分化出绿丝体、轴丝体及假根; 18d,轴丝体上的侧枝顶端细胞以分生缢割的方式产生单细胞或多细胞芽胞; 40d,轴丝体上开始出现配子体原始细胞;之后,配子体原始细胞发育成桑椹状的幼小配子体。还对芽胞形态发育、生理生态及配子体发生过程的特点进行了分析和讨论。,CN 23-1480/

    构建毕业生就业指标体系

    Get PDF
    corecore