闽江流域生境质量时空演变特征与预测研究

流域生境是生物生存和可持续发展的物质基础与环境保障,土地利用变化是影响生境质量的重要因素,分析土地利用与区域生境质量时空演变特征,对区域生物多样性保护与土地可持续利用具有重要意义。以闽江流域为研究区,基于2000-2015年的土地利用空间数据,构建CA-Markov模型模拟2025-2040年现有发展与生态保护情景下土地利用空间数据,利用InVEST模型分析2000-2040年生境质量空间格局。结果表明：（1）闽江流域森林覆盖率较高,现状条件下水田、旱地、针阔混交林、灌木林、草地与湿地面积呈下降趋势,其中草地减幅最大,达44.64%,针叶林、阔叶林、水域、建设用地、交通用地、采矿场与裸地面积呈上升趋势,其中交通用地涨幅最大,达到227.27%;模拟的土地利用Kappa系数达89.09%,模拟结果较好,生态保护情景在未来土地利用格局优化上优势明显。（2）研究期内闽江流域总体呈现较高的生境质量,基本维持在0.82的水平,城乡建设用地区域是生境质量低值的主要分布区,福州与长乐分布有最大的生境质量低值聚集区;生境质量分布与地形条件存在一定相关性,低值区多为海拔较低的区域。（3）2000-2015年闽江流域生境质量总体呈现衰退趋势,且降幅逐期升高,最高达0.24%;现有发展情景下降的趋势未得到有效缓解,生态保护情景下降趋势逐步有效缓解,同时生境质量为优等的栅格数量占比最大,最高达87.42%。（4）闽江流域上中游区域生境水平较下游高,现有发展情景下这种差距出现扩张趋势,生态保护情景下各区域则基本维持住2015年的生境质量水平。研究结果可为闽江流域土地资源可持续利用与生物多样性保护提供科学依据和决策参考,促进区域可持续发展。     

Analgesic-antitumor peptide inhibits proliferation and migration of SHG-44 human malignant glioma cells

Malignant gliomas, the most common subtype of primary brain tumors, are characterized by high proliferation, great invasion, and neurological destruction and considered to be the deadliest of human cancers. Analgesic-antitumor peptide (AGAP), one of scorpion toxic polypeptides, has been shown to have antitumor activity. Here, we show that recombinant AGAP (rAGAP) not only inhibits the proliferation of gliomas cell SHG-44 and rat glioma cell C6, but also suppresses the migration of SHG-44 cells during wound healing. To explain these phenomena, we find that rAGAP leads to cell cycle of SHG-44 arrested in G1 phase accompanied by suppressing G1 cell cycle regulatory proteins CDK2, CDK6, and p-RB by means of the down-regulated protein expression of p-AKT. Meanwhile, rAGAP significantly decreases the production of NF-κB, BCL-2, p-p38, p-c-Jun, and p-Erk1/2 and further suppresses the activation of VEGF and MMP-9 in SHG-44 cells. These findings suggest rAGAP inhibit proliferation and migration of SHG-44 cells by arresting cell cycle and interfering p-AKT, NF-κB, BCL-2, and MAPK signaling pathways.     

Towards operational cost minimization for cloud bursting with deadline constraints in hybrid clouds

In hybrid clouds, there is a technique named cloud bursting which can allow companies to expand their capacity to meet the demands of peak workloads in a low-priced manner. In this work, a cost-aware job scheduling approach based on queueing theory in hybrid clouds is proposed. The job scheduling problem in the private cloud is modeled as a queueing model. A genetic algorithm is applied to achieve optimal queues for jobs to improve the utilization rate of the private cloud. Then, the task execution time is predicted by back propagation neural network. The max–min strategy is applied to schedule tasks according to the prediction results in hybrid clouds. Experiments show that our cost-aware job scheduling algorithm can reduce the average job waiting time and average job response time in the private cloud. In additional, our proposed job scheduling algorithm can improve the system throughput of the private cloud. It also can reduce the average task waiting time, average task response time and total costs in hybrid clouds.     

孟加拉虎粪便放线菌的分离及其多样性

【目的】建立有效分离动物粪便放线菌的方法,认识孟加拉虎粪便放线菌的多样性。【方法】从预处理、抑制剂、培养基三个方面考虑,采用平板稀释的分离方法。用细菌通用引物扩增获得放线菌菌株的16SrRNA基因,根据系统发育分析进行鉴定。【结果】孟加拉虎粪便样品中,可培养放线菌的菌落平均数量为1.10×108cfu/g(粪便湿重);对分离到的110株纯培养放线菌的16S rRNA基因部分序列分析表明:它们分布于10个科、12个属,主要是一些菌丝分化程度低的放线菌,如:Arthrobacter、Dietzia、Kocuria、Corynebacterium、Microbacterium等;产丝的放线菌主要以Streptomyces占优势,约占分离到放线菌总数的64%。【结论】干热处理粪便样品可以大大提高放线菌的出菌率;添加多种抑制剂及不含天然成分的组合培养基较适合粪便放线菌的分离;孟加拉虎粪便中可培养放线菌的多样性较丰富。本研究提供的分离动物粪便放线菌的有效方法,为动物粪便放线菌资源的研究和开发利用提供了借鉴作用。     

血源乙肝疫苗人体反应及免疫效果观察报告

对我所１９８５年以来生产的１６０批血源乙型肝炎疫苗进行了３６８０例的现场人体观察,结果表明该疫苗接种后,全身及局部反应轻微,在随访期间未显示任何乙型肝炎病毒感染证据;儿童３针免疫后３个月抗－ＨＢｓ平均血清阳转率即达到９８％以上,具有高度的免疫原性。     

五种动物粪便纯培养放线菌的多样性及生物活性

【目的】以资源利用为出发点,研究了五种动物粪便放线菌的多样性及生物活性。【方法】从云南野生动物园采集5种半野生动物的新鲜粪便样品,用5种培养基分离其中的放线菌,将放线菌鉴定到属,测定纯培养放线菌的抗菌活性,抗肿瘤活性等。【结果】结果表明,所试5种动物粪便放线菌的种类非常丰富,组成各不相同,以链霉菌和微球菌占优势,可能存在大量未知放线菌;粪便放线菌的抗菌活性,抗肿瘤活性,酶活性,分解纤维素、角蛋白的活性非常普遍,尤其是具有抗肿瘤活性的菌株比例较大;产生的具有生物活性的次生代谢产物也是多种多样的。【结论】因此,粪便放线菌与土壤,海洋及植物的放线菌一样,是开发药物、农药和其他产品的重要来源之一,应当加强粪便放线菌的研究和保护利用。     

枸杞胼胝质酶基因克隆及在雄性不育材料中的表达分析

以雄性不育枸杞‘宁杞5号’和正常可育枸杞‘宁杞1号’为材料,提取不同发育时期枸杞花蕾RNA,反转录合成cDNA,利用胼胝质酶的β-1,3-葡聚糖酶属性进行同源克隆和半定量RT-PCR分析.结果表明:(1)所克隆的胼胝质酶基因(LG1)属于植物糖基水解酶第17家族基因,编码344个氨基酸,有5个氨基酸保守区在4种植物的花药β-1,3-葡聚糖酶基因中都存在.(2)LG1在正常可育枸杞花药中高量表达,在雄性不育枸杞花药中表达沉默,但基因序列并没有发生突变.(3)经苯胺蓝染色观察,雄性不育枸杞花药四分体分解受阻与LG1基因表达沉默同步.研究结果提示,LG1基因是受不育基因调控的下游基因,参与了枸杞花粉的败育过程,LG1基因沉默是雄性不育枸杞花粉败育的一个重要原因.     

几种经济植物UFGT基因的生物信息学分析

本文根据在GenBank中已登录的葡萄、玉米、水稻、草莓、拟南芥和苹果等植物的类黄酮-3-O-葡萄糖基转移酶基因的核苷酸序列和氨基酸序列,应用生物信息学软件预测了其理化性质、疏水性/亲水性、导肽、跨膜结构、卷曲螺旋结构、二级结构、功能结构域及高级结构,并构建了类黄酮-3-O-葡萄糖基转移酶蛋白家族的系统进化树.结果表明这几种植物的UFGT基因核苷酸序列除葡萄存在2个外显子外,其它植物均存在1个外显子.含量最丰富的氨基酸是Leu、Ala、Gly、Val和Ser等,除葡萄、苹果UFGT属于不稳定类蛋白外,其余均属于稳定类蛋白.进一步研究分析表明,这几种植物UFGT蛋白存在明显的疏水区和亲水区、信号肽、跨膜结构以及卷曲螺旋.二级结构组成上比例相似,并且都由α-螺旋、延伸链和无规则卷曲所组成.它们都存在UDPGT、COG1819和MGT等保守域.除了拟南芥外,其它几种植物都能够通过同源建模建立UFGT蛋白的三维结构.进化分析表明,把它们的UFGT 基因分成5个类群,其中3个大类群,另外陆地棉和野芭蕉的UFGT基因分别单独成一类.本工作将为深入研究该蛋白在植物花、果实和叶片等器官颜色变化中发挥的功能,开展生物大分子结构模拟以及药物设计提供抛砖引玉的作用.     

Fluorophosphates from Solid‐State Synthesis and Electrochemical Ion Exchange: NaVPO4F or Na3V2(PO4)2F3?

Vanadium‐based fluorophosphates are promising sodium‐ion battery cathode materials. Different phases of NaVPO₄F and Na₃V₂(PO₄)₂F₃ are reported in the literature. However, experiments in this work suggest that there could be confusions about the single‐phase NaVPO₄F in solid‐state synthesis. Here, systematic investigation of the mechanism underlying structural and compositional evolution of solid‐state synthesis (NaF:VPO₄ = 1:1) is determined by in situ and ex situ X‐ray diffraction and electrochemical measurements. Three reactions—3NaF + 3VPO₄ → Na₃V₂(PO₄)₂F₃ + VPO₄ (up to 500 °C), Na₃V₂(PO₄)₂F₃ + VPO₄ → Na₃V₂(PO₄)₃ + VF₃↑ (600–800 °C), and 2Na₃V₂(PO₄)₃ → 2(VO)₂P₂O₇ + Na₄P₂O₇ + amorphous products (above 800 °C)—are validated by in situ XRD and thermogravimetric analysis/differential scanning calorimetry. None of the products reported in this work is consistent with single‐phase NaVPO₄F at any temperature. It is speculated that the assignments of I4/mmm and C₂/c NaVPO₄F from solid‐state synthesis are incorrect, which are instead multiphase mixtures of Le Meins' Na₃V₂(PO₄)₂F₃, unreacted VPO₄, and hexagonal Na₃V₂(PO₄)₃. Liquid‐electrolyte‐based electrochemical ion exchange of LiVPO₄F produces a tavorite NaVPO₄F structure, which is very different from Le Meins' family of Na₃Al₂(PO₄)₂F₃ polymorphs.     

Dynamic data replacement and adaptive scheduling policies in spark

Improper data replacement and inappropriate selection of job scheduling policy are important reasons for the degradation of Spark system operation speed, which directly causes the performance degradation of Spark parallel computing. In this paper, we analyze the existing caching mechanism of Spark and find that there is still more room for optimization of the existing caching policy. For the task structure analysis, the key information of Spark tasks is taken out to obtain the data and memory usage during the task runtime, and based on this, an RDD weight calculation method is proposed, which integrates various factors affecting the RDD usage and establishes an RDD weight model. Based on this model, a minimum weight replacement algorithm based on RDD structure analyzing is proposed. The algorithm ensure that the relatively more valuable data in the data replacement process can be cached into memory. In addition, the default job scheduling algorithm of the Spark framework considers a single factor, which cannot form effective scheduling for jobs and causes a waste of cluster resources. In this paper, an adaptive job scheduling policy based on job classification is proposed to solve the above problem. The policy can classify job types and schedule resources more effectively for different types of jobs. The experimental results show that the proposed dynamic data replacement algorithm effectively improves Spark's memory utilization. The proposed job classification-based adaptive job scheduling algorithm effectively improves the system resource utilization and shortens the job completion time.