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71.
以培养学生独立思考能力为指导思想,针对传统食品微生物实验教学中的不足,从传统教学模式的改变、引导学生、吸引学生、提升实验课程地位和调整实验课程设置5个方面,对实验课程进行改革。食品微生物实验改革使学生的独立思考能力得到了良好的训练,同时也加强了学生的实践能力、创新能力、就业能力和创业能力的培育,为食品行业的快速发展服务。 相似文献
72.
科技论文是一个国家科技水平的反映,该文以详实的资料论述了中国科技论文在国际《SCI》《EI》《ISTP》三大检索工具中的地位;水土保持学术期刊在《中国科学引文索引》中的地位,并提出吸收国内水土保持科学优秀论文的有益建议。 相似文献
73.
Background, aim, and scope Forest plantations, widely grown for wood production, involve the selective promotion of single-tree species or replacement
of natural species by exotic tree species. Slash pine (Pinus elliottii) has been chosen for reforestation of infertile sandy soils in southeast Queensland, Australia. These exotic pine plantations
minimize soil and water losses and are important scientific study sites. The soil environment of these plantations, though
devoid of sufficient nutrients, organic carbon and other factors, harbors innumerable bacteria that may play a crucial role
in maintaining soil quality and ecosystem functions. These soil microorganisms also have the potential for use as sensitive
biological indicators to reflect environmental changes. It is therefore essential to understand the interrelationships among
bacterial communities and their environment by assessing their structural and functional diversity and their responses to
disturbances. The main aim of our investigation was to determine the diversity of bacterial communities in forest litters
and soil during the forest leaf litter decomposition using culture-dependent and culture-independent techniques.
Materials and methods A 25-cm (diameter) × 40-cm core sample was collected and fractionated into three subsamples designated E1 (L leaf litter layer),
E2 (F leaf litter layer), and E5 (0–10 cm soil layer). Both culture-dependent and culture-independent methods were applied
in this study. In the culture-independent study, a strategy of whole-community DNA extraction, polymerase chain reaction (PCR)
amplification followed by cloning and 16S rDNA sequence analysis was used; for culture-dependent study, the strategy included
sample plating and bacteria isolating, DNA extraction, PCR amplification, and 16S rDNA sequence analysis. The diversity similarities
between two bacterial communities and two methods are quantified using Jensen–Shannon divergence.
Results From culture-dependent study, 336 colonies in total were isolated and grouped from the three subsamples, and the 16S rRNA
sequence analysis from a representative isolate from each morphogroup (21 isolates) indicated that they belonged to the phyla
Actinobacteria, Firmicutes, and Proteobacteria. Culture-independent assessment based on 16S rRNA gene library comprising 194 clones revealed that members of the phylum Actinobacteria were absent in the culture-independent studies. Clones in libraries from E1 consisted exclusively of members of the Firmicutes. The majority of clones from E2 were related to Firmicutes (79%) and Proteobacteria (21%). Clones derived from E5 were mostly affiliated with Acidobacterium (42%), followed by unclassified bacteria (27%), Verrucomicrobiales (12%), Proteobacteria (11%), and Planctomycetes (8%).
Discussion This study showed that bacterial culturabilities in different fractions of leaf litters were similar, and both of them were
higher than the bacterial culturability in the soil. Unculturable bacterial diversity in the soil, however, was much higher
than the leaf litter bacterial diversity. The bacterial diversity on the top layer of leaf litters was slightly less than
that on the bottom layer of leaf litters. This might indicate that forest soils are a more complex environment than leaf litters
are and also that they might inhabit more unculturable microorganisms in the forest soils, which would need to be further
investigated. The leaf litter layer samples also demonstrate the significant difference between the bacterial community diversity
discovered by these two methods in this study. The information provided by assessing the different fractions of leaf litters
and forest soil has improved our understanding of the bacterial community distributions within the forest soil and the above-leaf
litters in an exotic pine plantation of subtropical Australia.
Conclusions This study represents the first attempt to examine the bacterial community in the different fractions of forest leaf litters
and soil in subtropical Australia. The data from this study show that the 16S rDNA clone libraries provided more comprehensive
phylogenetic diversity in the soil and leaf litter samples than the culture collections provided, and both the culture-dependent
and culture-independent studies revealed that the bacterial diversity present in the leaf litters was very different to that
present in the soil. The comparative analysis of bacterial communities in different fractions of leaf litters and soil samples
has also provided important baseline information about the bacterial diversity and composition in the exotic pine forest plantations.
Recommendations and perspectives The experimental data provided important information on the bacterial diversity in forest leaf litter and soil samples, though
additional surveys and comparisons at different locations would be needed to further characterize. In addition, combined methods
that can provide different parts of information on bacterial diversity are encouraged to be used in bacterial community study.
The established libraries of diverse 16S rRNA gene fragments from slash pine leaf litters and forest soil can be used to construct
specific DNA primers and probes to target bacterial groups of interest. It may then be possible to study the ecology of these
bacterial communities and the role of specific bacterial groups that contribute to the many interesting properties of these
environments. 相似文献
74.
75.
分析了全球气候变化和低碳经济背景下,高校图书馆建筑能耗的特点和节能减排的要求,提出了增强节能减排意识,指出了空调节能、照明节能、计算机节能等有效途径,并以湖南农业大学图书馆为例,重点介绍了空调节能减排和照明节能的做法与效果。 相似文献
76.
试论网络环境下高校图书馆信息资源的建设 总被引:1,自引:0,他引:1
分析目前高校在信息资源建设中存在的问题,并从三个方面提出高校图书馆信息资源建设的对策。 相似文献
77.
Thomas Derek Halling Heather K. Moberly Cathy Pepper Esther Carrigan 《Journal Of Agricultural & Food Information》2014,15(4):282-294
The Medical Sciences Library at Texas A&M University (MSL) participates in the National Library of Medicine (NLM) National Network of Libraries of Medicine South Central Region (NN/LM) Regional Resource Library outreach initiative. This program generally funds regional outreach activities promoting NLM information resources. The MSL and veterinary library community recognized practicing clinical veterinarians as an underserved population. The 2013–2014 MSL outreach proposal combined traditional activities with the development of materials to assist veterinarians with NLM resources, and exhibit to a national audience. This article provides an overview of the NN/LM SCR Resource Library Outreach Awards, an overview of MSL outreach activities for the year, and lessons learned. 相似文献
78.
2009—2011年《农业工程学报》被遴选为"中国科协精品期刊工程项目"期刊,围绕中国科协精品科技期刊工程项目的立项要求,《农业工程学报》编辑部开展了一系列工作;结合网络化办刊环境改进出版流程,缩短刊稿周期,加强学术不端论文的防范,坚持学术论文成果的大众媒体宣传。项目实施后期刊质量大幅度提高,影响不断扩大,期刊发展进入良性循环。该文对项目实施以来的工作、经验及成绩进行归纳分析,提出学术期刊的一种努力方向。 相似文献
79.
钟何香 《农业环境科学学报》2004,(6)
简述了医疗市场竞争日益加剧的现状,提出以创新管理制度、构建满足医院发展需求的服务模式为策略,重视人力资源和馆藏资源建设,深化传统图书馆信息服务。
相似文献80.
《Journal Of Agricultural & Food Information》2013,14(2):11-15
No abstract available for this article. 相似文献