27 research outputs found

    Breeding the strain 2A00015 (Candida parapsilosis) from Deep Sea and Preliminary Study of the Preparation of Microbio-diesel

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    微生物油脂(microbialoils)又称单细胞油脂(singlecelloil,SCO),即微生物以碳水化合物、碳氢化合物和普通油脂为碳源、氮源、辅以无机盐生产的油脂和另一些有商业价值的脂质。随着人口的增长、社会的进步使油脂需求量与自然资源短缺的矛盾日益加剧,环境污染日趋严重,开发新型油脂资源及清洁能源是当务之急。微生物生产油脂具有原料来源丰富、可再生、成本低、周期短、环境友好等优点,已引起人们的高度关注。开展微生物油脂的研究对解决人类面临的资源短缺、环境恶化等现实问题具有重要意义。 本文针对当前所关注的有关深海微生物、生物能源、废物综合利用3个热点问题,旨在寻找一株可以高效利用廉价碳源...Microbial oils (or single cell oil) refers to the oil produced by microorganisms with carbohydrate source (carbohydrates, hydrocarbons and ordinary oil), nitrogen sources and inorganic chemicals. With the population and social developing. New types of cleaning energy resource is key to solve problems among oil needs, shortage of natural resource and the serious environmental pollution. Now, many ...学位:理学硕士院系专业:生命科学学院_生物化学与分子生物学学号:2162010115230

    Breeding high-yield oil-producing strain to use cheap carbon source by UV induced protoplast mutagenesis

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    【目的】研究并建立利用原生质体紫外诱变技术选育可利用廉价碳源发酵的高产油新菌株的方法。【方法】采用1.5%蜗牛酶和1.0%纤维素酶混合液水解去除细胞壁得到2A00015(近平滑假丝酵母,CAndIdA PArAPSIlOSIS)的原生质体,将其放于紫外灯下诱变及再生壁培养,筛选获得可利用廉价碳源发酵的高产油酵母,并采用气相色谱质谱联用法(gC-MS)测定其脂肪酸组成。【结果】突变效果最好的突变菌株2A00015/25用葡萄糖发酵培养7 d后,其生物量、油脂产率和产油量分别为17.77 g/l、58.12%和10.32 g/l,较原始菌株分别提高了12.45%、23.32%和38.68%;利用废糖蜜发酵培养,其生物量、油脂产率和产油量分别为18.54 g/l、49.44%和9.17 g/l,较原始菌株分别提高了9.09%、21.16%和32.18%。利用废糖蜜培养其产油效率虽低于利用葡萄糖培养,但从环境保护及原材料成本的角度考虑,用废糖蜜作为碳源发酵培养产生油脂更具优势。诱变菌株利用废糖蜜发酵后产生油脂经检测含有8种脂肪酸,其脂肪酸组成与植物油近似,其中不饱和脂肪酸含量占脂肪酸总量的82.4%。【结论】通过利用原生质体紫外诱变技术,成功选育出一株新的可利用廉价碳源的高产油海洋菌株,产油率达到49.4%,提高了21.2%。[Objective] We used UV induced protoplast mutagenesis to study breed a new high-yielding lipid-producing strain which could use cheap carbon source.[Methods] Get the 1.5% glusulase and 1.0% cellulose solution.Hydrolyze to remove the cell wall and obtain the protoplast of 2A00015(Candida parapsilosis).Put it under the ultraviolet lamp for mutagenesis and cultivate regenrated wall.Then screen to get the high oil generated yeast which could be fermented by low-cost carbon source.Determine its fat acid components by gas chromatography with mass spectrometric(GC-MS).[Results] Cultivated the mutant strain with best mutation 2A00015/25 in the glucose.We found that the biomass, oil yield rate and oil production are separately 17.77 g/L, 58.12% and 10.32 g/L, which are separately 12.45%, 23.32% and 38.68% higher than the original strain.We have also cultivated the mutant strain in the waste molasses and found the biomass, oil yield rate and oil production are separately 18.54 g/L, 49.44% and 9.17 g/L, which are separately 9.09%, 21.16% and 32.18% higher than the original strain.The oil yield rate is lower in the waste molasses cultivation than that in glucose cultivation.However, in consideration of environment protection and cost of raw materials, the waste molasses is of much more advantages.It is tested that the fat generated from the waste molasses fermentation consists of eight kinds of fat acid.Its fat acid components are similar to the vegetable oil, in which the content of unsaturated fatty acid comprised 82.4% of the total fatty acid.[Conclusion] Basing on UV induced protoplast mutagenesis, we have successfully bred a new high-yielding oil strain which can make use of the low-cost carbon source, with its oil production rate 49.4% which has increased by 21.2%.深海(微)生物资源勘探与资源潜力评价项目(No.DY125-15-R-01

    ULK1 phosphorylates Exo70 to suppress breast cancer metastasis

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    乳腺癌是威胁女性生命健康的“头号杀手”,而远处转移是乳腺癌患者死亡的主要原因。因此,了解乳腺癌如何发动侵袭和转移,对于有效治疗乳腺癌、延长病人生存期具有重要意义。本研究中,该团队发现ULK1通过结合并磷酸化胞泌蛋白复合体关键亚基Exo70来抑制乳腺癌转移。ULK1对Exo70上Ser47,Ser59和Ser89位点的磷酸化,严重地削弱了Exo70的自身寡聚化和与其它胞外分泌复合体亚基的结合,进而减少了细胞运动伪足形成以及基质金属蛋白酶的分泌,从而抑制乳腺癌细胞的迁移和侵袭。该论文首次揭示了胞外分泌复合体重要成员Exo70在乳腺癌中受到ULK1和ERK1/2的双重磷酸化调控,从而使得乳腺癌细胞可以根据外环境来决定潜伏还是发动侵袭转移,为乳腺癌的治疗提供了新的理论基础。 本论文的通讯作者为占艳艳副教授、郭巍教授和胡天惠教授。医学院博士生毛丽媛、占艳艳副教授、吴斌博士和医学院博士生于强为共同第一作者。【Abstract】Increased expression of protein kinase ULK1 was reported to negatively correlate with breast cancer metastasis. Here we report that ULK1 suppresses the migration and invasion of human breast cancer cells. The suppressive effect is mediated through direct phosphorylation of Exo70, a key component of the exocyst complex. ULK1 phosphorylation inhibits Exo70 homo-oligomerization as well as its assembly to the exocyst complex, which are needed for cell protrusion formation and matrix metalloproteinases secretion during cell invasion. Reversely, upon growth factor stimulation, Exo70 is phosphorylated by ERK1/2, which in turn suppresses its phosphorylation by ULK1. Together, our study identifies Exo70 as a substrate of ULK1 that inhibits cancer metastasis, and demonstrates that two counteractive regulatory mechanisms are well orchestrated during tumor cell invasion.This work was supported by the grants from the National Natural Science Foundation of China (81572589, U1405228, 81472568, and 31770860), the Natural Science Foundation of Fujian grant (2017J06020, 2018J01400, 2017R1036-4, 2017R1036-6, 2016R1034-1, and 2016R1034-4), and the Xiamen Science and Technology grant (3502Z20159013) to Y.-y.Z. and T.H., and National Institute of Health R01 GM111128 to W.G.该论文的研究成果是在国家自然科学基金和福建省基金的资助下,与美国宾夕法尼亚大学和清华大学共同协作完成的

    Experimental study on reperfusion of intraocular lens

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    作者简介: 祁明信, 男, 1945 年7 月 出生, 教授、主任医师、博士研究生 导师, 主要从事白内障的基础与临 床研究。联系电话: 0591-83570887; E-mail:qihuang@netease. com 通讯作者: 黄秀榕,E-mail:[email protected][中文文摘]目的开展晶状体再灌注的离体和动物实验研究,并对再灌注人工晶状体技术进行评价。方法采用新鲜离体幼兔眼、离体猪眼、新西兰白兔眼,应用自行研制的人工晶状体材料,进行以下实验:(1)体外固化实验;(2)晶状体前囊膜微型撕囊及其稳固性实验;(3)经微型前囊膜开口超声乳化吸出晶状体内容物实验;(4)活的新西兰白兔眼内人工晶状体再灌注实验。结果(1)按硅酮聚合物与固化剂50:1的比例可获得柔软、弹性好、固化时间短(完全固化时间为60min)的注入材料;(2)晶状体前囊膜1.8~2.0mm的连续环形撕囊口具有较好的稳定性,可经该微型开口吸出晶状体内容物并灌注材料;(3)超声能量18%、流量25mL·min-1、负压120mmHg(1kPa=7.5mmHg)为晶状体内容物经微型前囊膜开口吸出的最佳条件;(4)注入灌注材料后可形成由晶状体囊膜包裹的、置换原晶状体皮质和核的、新的再灌注人工晶状体。结论采用再灌注人工晶状体的方法可进行新型人工晶状体再灌注,可为治疗白内障和老视提供参考。[英文文摘]Objective To carry out the experimental study on reperfusion of intraocular lens(IOLs) in vitro or in animal,and to assess the technique of IOLs reperfusion.Methods The following experiments were performed by using self-developed materials in fresh rabbit eyes and pig eyes in vitro,as well as in eyes of alive New-Zea-land rabbits:(1)Solidification study of self-developed material in vitro;(2)Continuous circular capsulorhexis(CCC) in anterior capsule of lens and its stability;(3)Draw of lens contents via phaco through mini-CCC;(4)IOLs ref illing in the eyes of alive New-Zea land rabbits. Results(1) Thematerialwhich was soft, springy and short-term solidification(full solidification time was 60 minutes) were obtained in certain proportion of geland solidified agent(50:1) in vitro; ( 2)The CCC in anterior capsule of lens with 1.8-2.0 mm diameter had very good stability. The lens contents were drawn and the materialwere refilled through themini-CCC; (3) The best conditions of drawing out lens contents through m ini-CCC were phaco energy 18% , flow 25 mL·min- 1, and negative pressure 120 mmH g (1kPa=7.5 mmHg);(4) The new refilled IOLs, which were wrapped by capsule of lens and were replaced original cortex and nucleus of lens, were obtained after thematerial refillied. Conc lusion. New IOLs are refilled through this method, which can prov ide reference for the treatment of cataract and presbyopia.福建省科技三项费用;教育厅重点资助项目基金资助(编号:K98041

    基于多目标遗传算法的Stewart平台运动学正解解算

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    Stewart平台的运动学解算是指对驱动杆杆长与动平台位姿的对应关系的求解。其运动学逆解只需根据空间坐标变换求得,而运动学正解需要对12个非线性方程进行解算。普通的数值解算方法迭代步数多,求解精度低。为解决Stewart平台运动学正解的解算问题,将pareto最优化理论引入遗传算法,提出一种基于多目标遗传算法(NSGA-II)和最小二乘理论结合的算法。利用算法生成上平台姿态,利用反解解算出姿态对应的杆长,与已知杆长进行最小二乘拟合分析,当拟合度极高时认为此时的位姿即为运动学正解结果。此算法将上平台姿态的6个参数求解转化成多目标最优化问题,其只需迭代102次左右便能输出最优解,单次结果输出用时在1 min以内,且求解的均方根值误差不超过0.1。是一种求解速度快、精度高的可行的运动学正解解算方法

    基于PSO-BPNN和Newton-Raphson法融合的并联机构正运动学解法

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    以并联机构为研究对象,针对求解正运动学时神经网络法易陷入局部最优及Newton-Raphson法对迭代初值敏感的问题,提出了一种融合PSO-BPNN(Back propagation neural network,BPNN)和Newton-Raphson法的正运动学通用求解算法。建立了并联机构逆运动学方程,得到驱动杆值,以此为训练样本,利用粒子群算法(Particle swarm optimization,PSO)优化BPNN(PSO-BPNN)模型获得位置正解,再以PSO-BPNN的正解值作为Newton-Raphson法的迭代初值对并联机构正运动学问题进行求解。为验证算法的有效性和通用性,给出了3-PCR、3-PPR两种并联机构的算例仿真。结果表明,由于迭代初值选取与目标值相差较大,导致Newton-Raphson法无法收敛;相比于PSO-BPNN算法,PSO-BPNN和Newton-Raphson法相结合得到的绝对误差最少降低了99.68%和99.96%,迭代次数更少;该方法既克服了神经网络法局部收敛性差的缺点,又避免了初值选取对Newton-Raphson法求解精度的影响,具有较好的通用性

    石墨烯的叔丁基对苯二酚修饰及其增强的电容行为

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    进化集成学习算法综述

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    进化集成学习结合了集成学习和进化算法两方面的优势,并在机器学习、数据挖掘和模式识别等领域被广泛应用。首先对进化集成学习算法的理论基础、组成结构及分类情况进行了概述。然后根据进化算法在集成学习中的优化任务,从样本选择、特征选择、集成模型参数组合优化、集成模型结构优化以及集成模型融合策略优化几个方面对当前进化集成学习领域的一些代表性研究成果进行了详细的综述,并分析和总结了各种进化集成学习算法的特点。最后对现有的进化集成研究的优缺点进行探讨,并给出了未来的研究方向

    灌水对大豆产量及化学品质的影响

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    采用田间小区试验,研究灌水对高油大豆和高蛋白大豆品种产量和品质的影响。试验结果表明,灌水使高油大豆的产量略有提高,较对照增产1.9%,对高蛋白大豆产量未表现出增产效果。灌水对不同品质的大豆蛋白质和脂肪含量影响不同,灌水可提高高油大豆品种脂肪含量,降低蛋白质含量。相反,灌水提高高蛋白大豆品种蛋白质含量,降低脂肪含量
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