• Title/Summary/Keyword: chemical diversity

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Diversity of Spider Communities in a Pesticide-treated Pine (Pinus densiflora) Forest

  • Park, Yung-Chul;Yoo, Jung-Sun;Kim, Joo-Pil
    • Journal of Ecology and Environment
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    • v.30 no.2
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    • pp.179-186
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    • 2007
  • The diversity of spider communities was investigated in the pine forest of Pinus densiflora in Songri-san, where chemical pesticides had been applied to control pine gall midge (Thecodiplosis japonensis). Spider communities were surveyed in four areas: a pesticide-untreated natural forest (area A), a forest with vinyl-covered ground surface (area B), an aldicarb-treated forest (area C) and a forest treated with a systemic pesticide (phosphamidon) (area D). A total of 74 spider species from 17 families were collected from the four survey areas. There were 54 species from 15 families in area A, 27 species from 12 families in area B, 29 species from 9 families in area C and 34 species from 9 families in area D, respectively. The species diversity of spider communities was highest in pesticide-untreated area A, and much lower in the other three areas. The monthly species diversity of spider communities was highest in May and lowest in January. The similarity of the spider communities was highest in areas B and D. The monthly similarity of the spider communities was highest in November and February. The dominant species was Clubiona jucunda (12.71%, N=304 individuals). According to our results, the application of aldicarb and phosphamidon dramatically decreased spider diversity and the number of individuals in the forests. Thus, the application of these two pesticides to natural forests should be restricted, or alternative pesticides need to be developed. Our results also indicated that application of the pesticides should be avoided in May and June when high spider diversity is expected.

Effects of Animal Manure Compost, Tillage Method and Crop System on Soil Properties in Newly Organic Corn Cultivation Field (신규 유기농 옥수수 재배 시 가축분 퇴비, 경운방법 및 작부체계가 토양 환경에 미치는 영향)

  • An, Nan-Hee;Lee, Sang-min;Cho, Jung-Rai;Nam, Hong-Sik;Jung, Jung-A;Kong, Min-jae
    • Journal of the Korea Organic Resources Recycling Association
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    • v.26 no.4
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    • pp.31-43
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    • 2018
  • This study was conducted to investigate the effects of organic farmland soil and nutrient management on soil properties depending on organic (animal manure compost and green manure [hairy vetch]) and chemical fertilization, tillage and no-tillage, and crop rotation (corn-wheat, corn-.hairy vetch). It was found that the application of organic matter such as animal manure compost and hairy vetch, increased the soil organic matter content, the soil microbial density and microbial biomass C content as compared with the chemical fertilizer treatment. It was also confirmed that the functional diversity of soil microbial community was increased. As a result of the comparison with the crop rotation and single cropping, the soil chemistry showed no significant difference between the treatments, but the corn-wheat and corn-hairy vetch rotation treatments tended to have higher microbial biomass C content and shannon's diversity index than the single cropping. Soil chemical properties of tillage and no-tillage treatments showed no significant difference between treatments. There was no statistically significant difference in substrate utilization of soil microbial community between tillage and no-tillage treatment. Correlation analysis between soil chemical properties and soil microbial activity revealed that soil organic matter content and exchangeable potassium content were positively correlated, with statistical significance, with substrate utilization, and substrate richness. To conclude, organic fertilization had positive effects on the short-term improvement of soil chemical properties and diversity of microbial communities.

Insect natural enemies as bioindicators in rice paddies

  • Ueno, Takatoshi
    • Korean Journal of Agricultural Science
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    • v.39 no.4
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    • pp.545-553
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    • 2012
  • In Asia, including Japan and Korea, rice paddies occupy the largest cultivated area in agricultural land. Rice paddies provide the habitats for many organisms including endemic species, sustaining high biodiversity. Insect natural enemies inhabiting rice paddies have an important function for rice production as agents of 'ecosystem services' because they play a major role in suppressing rice pests. The diversity and abundance of natural enemies can be a good index reflecting the 'healthiness' of agro-ecosystem services in rice paddies. The present study investigates whether insect natural enemies could be good biological indicators for general arthropod biodiversity and agricultural practice. First, the concept of ideal bio-indicators was summarized. The strategy to explore and select such bio-indicators was then proposed. Lastly, field survey was made to evaluate the abundance and biodiversity of natural enemies in Japanese rice paddies where chemical inputs, i.e., insecticide use, were different. The results showed that reduction of chemical inputs led to an increase in species richness or diversity of natural enemies including parasitoids and predators. Then, the data were analyzed to examine suitable indicator species to assess environmental soundness of agricultural practice and biodiversity in rice paddies. The density of several species of natural enemies did respond both to pesticide use and to general arthropod biodiversity. The analyses thus have indicated that natural enemies can be suitable as bio-indicators. Usefulness of indicator species in rice paddies is discussed in the context of ecologically sound agriculture.

Bacterial community analysis of stabilized soils in proximity to an exhausted mine

  • Park, Jae Eun;Lee, Byung-Tae;Kim, Byung-Yong;Son, Ahjeong
    • Environmental Engineering Research
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    • v.23 no.4
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    • pp.420-429
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    • 2018
  • Soil stabilization is a soil remediation technique that reduces the mobility of heavy metals in soils. Although it is a well-established technique, it is nonetheless essential to perform a follow-up chemical assessment via a leaching test to evaluate the immobilization of heavy metals in the soil matrix. Unfortunately, a standard chemical assessment is not sufficient for evaluation of the biological functional state of stabilized soils slated for agricultural use. Therefore, it is useful to employ a pyrosequencing-based microbial community analysis for the purpose. In this study, a recently stabilized site in the proximity of an exhausted mine was analyzed for bacterial diversity, richness, and relative abundance as well as the effect of environmental factors. Based on the Shannon and Chao1 indices and rarefaction curves, the results showed that the stabilized layer exhibited lower bacterial diversity than control soils. The prevalence of dominant bacterial populations was examined in a hierarchical manner. Relatively high abundances of Proteobacteria and Methylobacter tundripaludum were observed in the stabilized soil. In particular, there was substantial abundance of the Methylobacter genus, which is known for its association with heavy metal contamination. The study demonstrated the efficacy of (micro)biological assessment for aiding in the understanding and post-management of stabilized soils.

Biodiversity, Spore Density and Root Colonization of Arbuscular Mycorrhizal Fungi at Expressway Cut-slopes in Korea

  • Lee, Kyung Joon;Lee, Kyu Hwa;Tamolang-Castillo, Evangeline;Budi, Sri Wilarso
    • Journal of Korean Society of Forest Science
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    • v.98 no.5
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    • pp.539-547
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    • 2009
  • This study was conducted to investigate the arbuscular mycorrhizal fungal biodiversity, spore density and root colonization in relation to site ages at expressway cut-slopes in Korea. Stabilization of exposed surface involved soil amendments and spraying seed mixture of turf grasses and/or nitrogen-fixing shrub species. Eighteen sites were selected with varying ages (2 to 16 years). Soil samples collected in October from each site were analyzed for fungal diversity and spore counts. Fine root samples from the plants were assayed for fungal colonization. Of the total 37 plants inspected in the sites, 26 species had endomycorrhizal colonization with an average root colonization rate of 18%, and with a range from 1 to 67%. The average endomycorrhizal colonization rate of initially introduced Festuca arundinacea which became the most dominant grass in later stage showed 22.8%, while that of Lespedeza bicolor which became the most dominant woody species were 21.6%. Naturally-invading Robinia pseudoacacia showed higher colonization rate in the old sites. Although site age did not show significant effects on fungal diversity, the root colonization rates of initially introduced plants decreased with the site aging, while those of invading plants increased with aging of the sites. The soil chemical properties, pH, N, and P contents, were negatively correlated with spore density, root colonization and endomycorrhizal species diversity. A total of forty arbuscular mycorrhizal fungal species in seven genera were identified. Of the 40 species, Acaulospora lacunosa, Glomus aggregatum, Glomus constrictum, Scutellospora erythropa, and Acaulospora spinosa were the five most dominant species in the decreasing order.

Nationally-Funded R&D Projects Data Based Dynamic Convergence Index Development: Focused On Life Science & Public Health Area (국가 연구개발(R&D) 과제 데이터 기반 동적 융합지표에 관한 연구: 생명·보건의료 분야를 중심으로)

  • Lee, Doyeon;Kim, Keunhwan
    • Journal of the Korean Society of Industry Convergence
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    • v.25 no.2_2
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    • pp.219-232
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    • 2022
  • The aim of this study is to provide the dynamic convergence index that reflected the inherent characteristics of the convergence phenomenon and utilized the nationally-funded R&D projects data, thereby suggesting useful information about the direction of the national convergence R&D strategy. The dynamic convergence index that we suggested was made of two indicators: persistency and diversity. From a time-series perspective, the persistency index, which measures the degree of continuous convergence of multidisciplinary nationally-funded R&D projects, and the diversity index, which measures the degree of binding with heterogeneous research areas. We conducted the empirical experiment with 151,248 convergence R&D projects during the 2015~2021 time period. The results showed that convergence R&D projects in both public health and life sciences appeared the highest degree of persistency. It was presumed that the degree of persistency has increased again due to the COVID-19 pandemic. Meanwhile, the degree of diversity has risen with combining with disciplinary such as materials, chemical engineering, and brain science areas to solve social problems including mental health, depression, and aging. This study not only provides implications for improving the concept and definition of dynamic convergence in terms of persistency and diversity for national convergence R&D strategy but also presented dynamic convergence index and analysis methods that can be practically applied for directing public R&D programs.

Fashion Paradigm of 'Slowness' on Contemporary Fashion (현대 패션에 나타난 '느림'의 패러다임)

  • Ham, Youn-Ja
    • Fashion & Textile Research Journal
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    • v.11 no.4
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    • pp.527-536
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    • 2009
  • The purpose of this study is to consider the characteristics of fashion paradigm on contemporary fashion in pursuit of social change towards 'slowness'. As for the research methodology, literature survey has been undertaken. The results of this study can be summarized as followings. First, eco-friendly ethics towards sustainability is in taking action. The concept of 'cradle-to-cradle' is realized through reuse, recycle, organic material, and no use of chemical. Second, local diversity is revolving quality and longevity. Good quality of fashion made by artisans and specificity in local area is to be kept last. Third, people are recast in roles from simple consumers to self-made producers of their clothes. Users of clothes are more active and skilled role in practice of handmade, reform, DIY, and open-source design. In Conclusion, the fashion paradigm of 'slowness' is about designing, producing, consuming and living better to combine ideas for sense of nature's time, culture's time and people's time.

Matrix Metalloproteinase: Inhibitory Effect of Marine Substances on MMP-2 and MMP-9

  • Nguyen, Van-Tinh;Qian, Zhong-Ji;Jung, Won-Kyo
    • Journal of Integrative Natural Science
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    • v.4 no.4
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    • pp.255-265
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    • 2011
  • Marine ecosystems are often characterized by a high biological diversity, and it corresponds to a high chemical diversity. Up to present, more than 20,000 new bioactive substances have been isolated from marine organisms, where considerable numbers of these naturally occurring derivatives are developed as potential candidates for pharmaceutical application. In this process, screening of natural products from marine organisms that could potentially inhibit the expression of metalloproteinases has gained a huge popularity. Cancer is considered as one of the deadliest diseases in the medical field. Matrix metalloproteinase (MMPs) can degrade extracellular matrix (ECM) components and play important roles in a variety of biological and pathological processes. Matrix metalloproteinase inhibitors (MMPIs) have been identified as potential therapeutic candidates for metastasis, arthritis, chronic inflammation and wrinkle formation.

From rheometry to rheology

  • Sridhar, T.
    • Korea-Australia Rheology Journal
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    • v.12 no.1
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    • pp.39-53
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    • 2000
  • Using a variety of examples from the recent literature on extensional flow of polymer solutions, this paper shows that simple constitutive equations are unable to capture the diversity of chain conformations in such flows. Such diversity is a feature of extensional flows and arises because deformation leads to significant chain extension. Substantial local extension appears even at low strains and the behaviour of these stretched out portions influences the dynamics of the chain and makes a dominant contribution to the stress. Both the distribution function and the chain conformation appear to follow different paths during stretching and relaxation. As a result the second moment of the distribution function does not contain enough information to correctly predict the dynamics. Resolution of this deficiency in simple constitutive models is one of the challenges for rheology.

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Ambient Mass Spectrometry in Imaging and Profiling of Single Cells: An Overview

  • Bharath Sampath Kumar
    • Mass Spectrometry Letters
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    • v.14 no.4
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    • pp.121-140
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    • 2023
  • It is becoming more and more clear that each cell, even those of the same type, has a unique identity. This sophistication and the diversity of cell types in tissue are what are pushing the necessity for spatially distributed omics at the single-cell (SC) level. Single-cell chemical assessment, which also provides considerable insight into biological, clinical, pharmacodynamic, pathological, and toxicity studies, is crucial to the investigation of cellular omics (genomics, metabolomics, etc.). Mass spectrometry (MS) as a tool to image and profile single cells and subcellular organelles facilitates novel technical expertise for biochemical and biomedical research, such as assessing the intracellular distribution of drugs and the biochemical diversity of cellular populations. It has been illustrated that ambient mass spectrometry (AMS) is a valuable tool for the rapid, straightforward, and simple analysis of cellular and sub-cellular constituents and metabolites in their native state. This short review examines the advances in ambient mass spectrometry (AMS) and ambient mass spectrometry imaging (AMSI) on single-cell analysis that have been authored in recent years. The discussion also touches on typical single-cell AMS assessments and implementations.