• 제목/요약/키워드: Structural diversity

검색결과 277건 처리시간 0.024초

Heterogeneous Habitat for Increasing Biological Diversity

  • Lee, Sang-Don
    • 환경생물
    • /
    • 제21권4호
    • /
    • pp.337-341
    • /
    • 2003
  • Habitat heterogeneity can enhance biological diversity by providing variation in structural diversity. This paper reviewed heterogeneous habitat serves as a population stability and superior demographic performance (e.g., high density, survivorship, reproductive rate) can be observed compared with organisms with inferior demographic performance. The idea of habitat variation has been further developed in modelling. Furthermore the size and configuration (distribution) of a patch (of a particular habitat type) become effective for the stability of population through hiding places and food resources. Species diversity is related to habitat complexity that provides structural diversity to ground -dwelling organisms. Finally coarse woody debris can enhance habitat complexity thus stabilizing population fluctuation and increasing survivorship.

Diversification and domain evolution of molluskan metallothioneins: a mini review

  • Nam, Yoon Kwon;Kim, Eun Jeong
    • Fisheries and Aquatic Sciences
    • /
    • 제20권6호
    • /
    • pp.8.1-8.18
    • /
    • 2017
  • Background: Metallothionein (MT) is a multifunctional protein playing important roles in homeostatic regulation and detoxification of metals. Mollusk species have been considered as useful sentinel platforms for MT-based biomarker approaches, and they have been reported to display an extraordinary structural diversity of MT proteins. However, potential diversity of molluskan MTs has not been fully explored and recent updates have suggested the need of revision of evolutionary hypothesis for molluskan MTs. Results: Based on bioinformatic analysis and phylogenetic evidences, novel divergence mechanisms and paths were hypothesized in both gastropod and bivalve MT groups. Our analyses are suggestive of the taxon- or lineage-specific domain multiplication/duplication from the ancestral or prototypic MT. Diversification and selection of molluskan MTs might be driven by the needs for acquiring metal selectiveness, specialized novel function, and improved capacity of metal detoxification under environmentally stressed conditions. Conclusion: The structural diversity and variations of molluskan MTs are significantly larger than previously understood. Undoubtedly, molluskan MTs have undergone dynamic divergent processes in their evolutionary histories, giving rise to the great diversity of domain structures in extant MT isoforms. Novel evolutionary paths for molluskan MTs newly proposed in this review could shed additional light onto the revision of the hypothesis for evolutionary differentiation of MTs in the molluskan lineage.

An Overview of Different Techniques on the Microbial Community Structure, and Functional Diversity of Plant Growth Promoting Bacteria

  • Kim, Kiyoon;Islam, Rashedul;Benson, Abitha;Joe, Manoharan Melvin;Denver, Walitang;Chanratan, Mak;Chatterjee, Poulami;Kang, Yeongyeong;Sa, Tongmin
    • 한국토양비료학회지
    • /
    • 제49권2호
    • /
    • pp.144-156
    • /
    • 2016
  • Soil is a dynamic biological system, in which it is difficult to determine the composition of microbial communities. Knowledge of microbial diversity and function in soils are limited because of the taxonomic and methodological limitations associated with studying the organisms. In this review, approaches to measure microbial diversity in soil were discussed. Research on soil microbes can be categorized as structural diversity, functional diversity and genetic diversity studies, and these include cultivation based and cultivation independent methods. Cultivation independent technique to evaluate soil structural diversity include different techniques such as Phospholipid Fatty Acids (PLFA) and Fatty Acid Methyl Ester (FAME) analysis. Carbon source utilization pattern of soil microorganisms by Community Level Physiological Profiling (CLPP), catabolic responses by Substrate Induced Respiration technique (SIR) and soil microbial enzyme activities are discussed. Genetic diversity of soil microorganisms using molecular techniques such as 16S rDNA analysis Denaturing Gradient Gel Electrophoresis (DGGE) / Temperature Gradient Gel Electrophoresis (TGGE), Terminal Restriction Fragment Length Polymorphism (T-RFLP), Single Strand Conformation Polymorphism (SSCP), Restriction Fragment Length Polymorphism (RFLP) / Amplified Ribosomal DNA Restriction Analysis (ARDRA) and Ribosomal Intergenic Spacer Analysis (RISA) are also discussed. The chapter ends with a final conclusion on the advantages and disadvantages of different techniques and advances in molecular techniques to study the soil microbial diversity.

EvoSNP-DB: A database of genetic diversity in East Asian populations

  • Kim, Young Uk;Kim, Young Jin;Lee, Jong-Young;Park, Kiejung
    • BMB Reports
    • /
    • 제46권8호
    • /
    • pp.416-421
    • /
    • 2013
  • Genome-wide association studies (GWAS) have become popular as an approach for the identification of large numbers of phenotype-associated variants. However, differences in genetic architecture and environmental factors mean that the effect of variants can vary across populations. Understanding population genetic diversity is valuable for the investigation of possible population specific and independent effects of variants. EvoSNP-DB aims to provide information regarding genetic diversity among East Asian populations, including Chinese, Japanese, and Korean. Non-redundant SNPs (1.6 million) were genotyped in 54 Korean trios (162 samples) and were compared with 4 million SNPs from HapMap phase II populations. EvoSNP-DB provides two user interfaces for data query and visualization, and integrates scores of genetic diversity (Fst and VarLD) at the level of SNPs, genes, and chromosome regions. EvoSNP-DB is a web-based application that allows users to navigate and visualize measurements of population genetic differences in an interactive manner, and is available online at [http://biomi.cdc.go.kr/EvoSNP/].

The Influence of Transformational Leadership on Employees' Innovation in Universities of UAE: Mediating Effect of Technological Diversity

  • ALMASKARI, Tariq Humaid;MOHAMAD, Effendi;YAHAYA, Siti Norbaya;JALIL, Muhammad Farhan
    • The Journal of Asian Finance, Economics and Business
    • /
    • 제8권7호
    • /
    • pp.657-669
    • /
    • 2021
  • This study seeks to empirically investigate the impact of transformational leadership on employees' innovation with the mediating effect of technological diversity. Employees have evolved into leaders in organizing work within institutions over the last few decades. This shift presents new demands for leaders, who are forced to reinvent individual workers while also improving workplace innovation. This research proposes a conceptual model for considering transformational leadership and the impact of technological diversity on innovation. Structured questionnaire is used in the study and the analysis of the data from 633 employees of universities in the United Arab Emirates uses stratified sampling technique and hypotheses verified through Structural Equations Modelling (AMOS-21). According to the results, transformational leadership has a big effect on employees' innovation. Furthermore, in the relationship between transformational leadership and workforce innovation, technological diversity has a partial mediation impact. This research adds to the growing body of knowledge about how transformational leadership influences employees' innovation and how it affects employees' success, especially in the context of UAE-based universities. Overall, this research contributes to the previous studies wherein transformational leadership plays a critical role in influencing the innovative performance of employees and that, in turn, will promote diversification of technology in the organization.

Discrete optimal sizing of truss using adaptive directional differential evolution

  • Pham, Anh H.
    • Advances in Computational Design
    • /
    • 제1권3호
    • /
    • pp.275-296
    • /
    • 2016
  • This article presents an adaptive directional differential evolution (ADDE) algorithm and its application in solving discrete sizing truss optimization problems. The algorithm is featured by a new self-adaptation approach and a simple directional strategy. In the adaptation approach, the mutation operator is adjusted in accordance with the change of population diversity, which can well balance between global exploration and local exploitation as well as locate the promising solutions. The directional strategy is based on the order relation between two difference solutions chosen for mutation and can bias the search direction for increasing the possibility of finding improved solutions. In addition, a new scaling factor is introduced as a vector of uniform random variables to maintain the diversity without crossover operation. Numerical results show that the optimal solutions of ADDE are as good as or better than those from some modern metaheuristics in the literature, while ADDE often uses fewer structural analyses.

조직 내 다양성 관리와 종업원의 이직의도: 지각된 조직후원인식의 매개효과를 중심으로 (Managing workplace diversity and employees' turnover intention: The mediating role of perceived organizational support)

  • 김혜경;이웅희
    • 디지털융복합연구
    • /
    • 제12권10호
    • /
    • pp.145-156
    • /
    • 2014
  • 본 연구의 주요 목적은 조직 내 다양성 관리, 종업원의 이직 의도, 그리고 지각된 조직 후원과의 구조적 관계를 살펴보는 것이다. 또한 조직 내 다양성 관리와 이직 의도 간의 관계에서 지각된 조직 후원의 매개적 역할에 대해서도 살펴보는 것이다. 연구 목적을 달성하기 위해 선행연구 리뷰와 설문지법을 이용한 실증적 분석을 실시하였으며, 연구결과 조직 내 다양성 관리와 종업원의 이직 의도와는 부(-)의 영향관계가 존재하지 않았으나, 다양성 관리가 지각된 조직 후원에는 정(+)의 영향을 미치는 것으로 나타났다. 지각된 조직 후원은 종업원의 이직 의도에 부(-)의 영향을 미치는 것으로 나타났다. 또한 지각된 조직 후원은 조직 내 다양성 관리가 종업원의 이직 의도에 미치는 영향 관계에서 매개역할을 하는 것으로 나타났다. 이러한 연구결과를 바탕으로 종업원의 이직 의도를 줄이고 최종적으로 성과 향상을 위한 방안에 대해 논의하고 시사점을 제시하였다.

Diversity and Composition of Tree Species in Madhupur National Park, Tangail, Bangladesh

  • Rahman, Md. Rayhanur;Hossain, Mohammed Kamal;Hossain, Md. Akhter
    • Journal of Forest and Environmental Science
    • /
    • 제35권3호
    • /
    • pp.159-172
    • /
    • 2019
  • Madhupur National Park (MNP) is one of the last remaining patches of old-growth natural Sal forest left in Bangladesh where the forest is tropical moist deciduous type. A study was revealed to assess the tree species diversity and composition in this area. For determining tree species the study was conducted through extensive random quadrat survey methods with $20m{\times}20m$ sized plots. Results of the study indicated that there were 139 tree species belonging to 100 genera and 40 families. The quadrat survey assessed the basal area, stem density, diversity indices and importance value index of the tree species having ${\geq}5cm$ D.B.H (Diameter at Brest Height). The basal area and stem density of the tree species were $20.689{\pm}1.08m^2/ha$ and $1412.93{\pm}64.27stem\;ha^{-1}$ while, diversity indices, i.e. Shannon-Wiener's diversity, Simpson's evenness, Margalef's species richness and Pielou's dominance indices indicated poor diversity in comparison to that of other PAs (Protected Areas) in South-Eastern region of Bangladesh. The structural composition based on height and D.B.H through reverse-J shaped curve indicated higher regeneration and recruitment but removal of trees of large growth classes. Sal (Shorea robusta) was the most dominant tree species that accounts 75% of the total tree individuals in the natural forest patches. However, some associates of Sal, i.e. Bhutum (Hymenodictyon orixensis), Gadila (Careya arborea), and Kusum (Schleichera oleosa) etc. were seemed to be rare in MNP.

Comparative Enzyme Production by Fungi from Diverse Lignocellulosic Substrates

  • Sin, Marie K.W.;Hyde, Kevin D.;Pointing, Stephen B.
    • Journal of Microbiology
    • /
    • 제40권3호
    • /
    • pp.241-244
    • /
    • 2002
  • Fungi commonly encountered on monocotyledonous substrates were evaluated for their in vitro ability to produce enzymes involved in lignocellulose breakdown. Most were capable of structural polysac-charide utilization, but few produced enzymes associated with lignin breakdown. None of the mono-cotyledon-inhabiting fungi produced reactions as strongly as wood decay fungi.

경쟁과 다양성: 방송관련법의 목적의 관점 (Competition and Diversity: Perspective of the Objectives of Broadcasting-related Laws)

  • 홍대식
    • 법제연구
    • /
    • 제44호
    • /
    • pp.63-101
    • /
    • 2013
  • 이 글에서는 먼저 경쟁과 다양성이 미디어 정책의 구체적인 수단을 규정한 방송관련법이 추구하는 주된 목적이 된다는 것을 전제로 하여 각각의 개념과 구성요소 그리고 그 제도적 구현의 모습을 살펴보고, 특정분야의 경쟁법으로서의 방송관련법에서는 경쟁 목적이 차별성 요인을 갖는 한편 다양성 가치도 특수성을 갖는다는 논의를 전개한다. 다음으로 경쟁과 다양성 가치를 조화롭게 실현하기 위해서는 방송시장 특유의 구조적 규제수단을 포함하는 특별한 경쟁규칙이 필요하다고 전제하면서, 방송관련법상 경쟁 목적 규제와 다양성 목적 규제에 대하여 개선되어야 할 방향을 다음과 같이 제시한다. 첫째, 경쟁 목적 규제의 개선 방안이다. 사전적인 상태적 규제로서의 시청점유율 규제와 사후적인 행위규제로서의 금지행위 규제는 다양성 가치를 추구하면서도 원인적 규제를 대체하는 데 중요한 역할을 할 수 있다. 이를 위하여 공정거래법의 위법성 판단방식을 유추하여 다양성 관련 요소를 금지행위의 위법성 판단기준의 고려요소로 하는 방식을 구체적으로 개발할 필요가 있다. 둘째, 다양성 목적 규제의 개선 방안이다. 이는 규제 목적의 설정, 대체가능한 규제수단의 식별, 규제 목적에 맞는 규제수단과 규제수준의 선택이라는 3가지 관점에서 검토될 수 있다. 이러한 관점에서 다양성 가치가 단순한 수사적 도구에 그치지 않고 평가 및 분석 도구로 사용될 수 있는 제도적 수단 위주로 규제 틀을 개선하는 한편, 경쟁과 같은 경제적 목적과의 조화를 고려할 때 불합리해 보이는 규제에 대하여는 이를 유지할 것인가 또는 어느 정도로 유지할 것인가를 신중하게 재검토해야 한다.