• The Korean Journal of Ecology
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• v.15 no.3
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• pp.231-246
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• 1992

In order to estimate effects of air pollution for pinus thunbergii forests arounding onsan industrial complex, structure of forest vegrtation was surveyed. In the survey of forest vegetation, pinus densiflora have been died or being withered, and importance value(I.V) of rhododendron mucromulatum and lespedeza spp. were low at the vicinity of industrial complex. Especially lespedeza maximowiczii and l. maritima were not entirely appeared at the vicinity of industrial complex. I.V. of quercus serrata, robinia pseudoacacia and alnus firma were preferably high at the vicinity of industrial complex, and those of smilax china, rubus crataegifolius and rhus trichocarpa were similar at every site and it could be guessed that those had a tolerance. Number of species had a difference over 10 species at the vicinity of industrial complex as compared with those of remote sites, and species diversity showed highly at the farther sites of industrial complex, and also at the low layer, number of species, species diversity and evennes were low at the vicinity of industrialcomplex and species weakened to air pollution were disappearing. It was possible that forest vegetation would be changed from pinus spp. to community of a. firma and r. pseudoacacia.

• Journal of Communications and Networks
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• v.8 no.3
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• pp.286-289
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• 2006

Measurement results are presented for the effects of people moving near and across short-range indoor propagation links at 2.45 GHz (ISM band). Excess loss due to scattering and blockage by human bodies in the vicinity of one terminal were measured for different radio links in an office environment. Statistics on fades due to human body motion are given. Polarization coupling (depolarization) for various radio links was measured, and correlation of polarization components is discussed as a basis for using polarization diversity reception in short-range indoor systems.

• Korean Journal of Plant Taxonomy
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• v.51 no.3
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• pp.192-197
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• 2021

In the flora of Korea, Carex L. is one of the most species-rich genera. Among nearly 157 Carex taxa, less than 30 have had chromosome numbers reported. We report the meiotic chromosome numbers of eight Carex taxa from Korean populations, which include the first count for C. accrescens Ohwi (n = 37_II) and the first chromosome investigations of Korea populations for three taxa: C. bostrychostigma Maxim. (n = 22_II), C. lanceolata Boott (n = 36_II), and C. paxii Kuk. (n = 38_II). In most species, chromosome counts observed in the study are included in the variation ranges of previous chromosome numbers. However, C. bostrychostigma Maxim. (n = 22_II) and C. planiculmis Kom. (n = 29_II) are assigned new chromosome numbers. Carex is known to have holocentric chromosomes, lacking visible primary constrictions and exhibiting great variance in its chromosome number. Further investigations of the diversity of Carex chromosomes will provide basic information with which to understand the high species diversity of the genus.

• Animal Systematics, Evolution and Diversity
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• v.35 no.1
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• pp.21-29
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• 2019

The earwig Proreus simulans($St{\aa}l$, 1860) has been recently reported from Jeollanam-do in the far southern section of the Korean Peninsula. Natural photographs of this species were obtained from Gwangyang Province for the first time in 2013, with specimens being physically collected in light traps from Suncheon Province in 2018. The species is widely distributed throughout the Oriental region, where its main habitat is lowland paddy fields. The earwig belongs to family Chelisochidae, subfamily Chelisochinae, and genus Proreus, which are newly recognized in Korea. The diversity of the order Dermaptera is currently estimated to be 6 families, 14 genera, and 24 species in Korea.

• Microbiology and Biotechnology Letters
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• v.49 no.1
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• pp.1-8
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• 2021

Human breast milk is a potential source of bacteria for the development of the intestinal microbiota of infants. Several species within the genera Lactobacillus and Bifidobacterium were demonstrated to shape the gut microbiota of infants. In this study, the bacterial diversity was investigated in the breast milk and feces of a mother-infant pair, and probiotic candidates were identified. Importantly, the novel L. gasseri EJL and B. breve JTL strains were isolated from breast milk and infant feces samples, respectively; their completed genome was resolved using de novo sequencing. In addition, the bacterial composition in the infant's feces at 1 week revealed the prevalence of Bifidobacterium and Streptococcus; a higher diversity was observed after 3 weeks. In particular, the abundance of Akkermansia was sharply increased at 7 weeks, further increasing thereafter, up to 15 weeks. Our results suggest that human breast milk and infant's feces are a source of probiotic candidates.

• Genes and Genomics
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• v.40 no.12
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• pp.1319-1329
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• 2018

SSRs were successfully isolated from the Perilla crop in our current study, and used to analyze Perilla accessions from East Asia. Analyses of the clear genetic diversity and relationship for Perilla crop still remain insufficient. In this study, 40 new simple sequence repeat (SSR) primer sets were developed from RNA sequences using transcriptome analysis. These new SSR markers were applied to analyze the diversity, relationships, and population structure among 35 accessions of the two cultivated types of Perilla crop and their weedy types. A total of 220 alleles were identified at all loci, with an average of 5.5 alleles per locus and a range between 2 and 10 alleles per locus. The MAF (major allele frequency) per locus varied from 0.229 to 0.943, with an average of 0.466. The average polymorphic information content (PIC) value was 0.603, ranging from 0.102 to 0.837. The genetic diversity (GD) ranged from 0.108 to 0.854, with an average of 0.654. Based on population structure analysis, all accessions were divided into three groups: Group I, Group II and the admixed group. This study demonstrated the utility of new SSR analysis for the study of genetic diversity and population structure among 35 Perilla accessions. The GD of each locus for accessions of cultivated var. frutescens, weedy var. frutescens, cultivated var. crispa, and weedy var. crispa were 0.415, 0.606, 0.308, and 0.480, respectively. Both weedy accessions exhibited higher GD and PIC values than their cultivated types in East Asia. The new SSR primers of Perilla species reported in this study may provide potential genetic markers for population genetics to enhance our understanding of the genetic diversity, genetic relationship and population structure of the cultivated and weedy types of P. frutescens in East Asia. In addition, new Perilla SSR primers developed from RNA-seq can be used in the future for cultivar identification, conservation of Perilla germplasm resources, genome mapping and tagging of important genes/QTLs for Perilla breeding programs.

• Korean Journal of Plant Taxonomy
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• v.42 no.1
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• pp.13-23
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• 2012

The trnL-F region islocated in the large single-copy region of the chloroplast genome. It consists of the trnL gene, the trnL intron, and the trnL-F IGS. Molecular evolution and phylogenetic relationships in Korean Thalictrum L. were investigated using data from the cpDNA trnL-F region. Bayesian and parsimony analyses of the data set with the gap characteristics recovered well-resolved trees that are topologically similar, with clades supported by some indels evolution. Indel events of cpDNA trnL-F in Korean Thalictrum were interpreted as phylogenetically informative characteristics. Sect. Physocarpum (excluding T. osmorhizoides) was an early-diverging group with in the genus and the remaining section formed strongly supported clades. Korean Thalictrum has various evolutionary patterns, such as the spatial distribution of the nucleotide diversity and transversion-type base substitutions in the trnL-F region.

• The Korean Journal of Mycology
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• v.42 no.1
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• pp.79-85
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• 2014

Forty-two endophytic fungi were isolated from the roots of coastal plants, such as Aster sphathulifolius Maxim., Aster tripolium L., Phragmites australis, and Puccinellia nipponica Ohwi, naturally growing in Taean peninsula. The identity of the endophytic fungal strains was analyzed using the sequence of internal transcribed spacer regions. All fungi belonged to the phylum Ascomycota, and they were classified into eight orders (Botryosphaeriales, Capnodiales, Diaporthales, Dothideales, Eurotiales, Helotiales, Hypocreales, and Pleosporales) and thirteen genera (Alternaria, Aureobasidium, Cadophora, Cladosporium, Davidiella, Diaporthe, Fusarium, Gibberella, Macrophomina, Metarhizium, Neosartorya, Penicillium, and Phoma). Among the analyzed fungi, the fungi belonging to the genus Penicillium in Eurotiales were the most widely distributed. The host plant Aster tripolium L. was found to contain the most diverse endophytic fungal species among the coastal plants.

• ALGAE
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• v.34 no.4
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• pp.277-288
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• 2019

Freshwater red algae of the order Batrachospermales are poorly studied in India and Nepal, especially on a molecular basis. During a survey in northeast India and east Nepal, six populations of the genus Sheathia were found and analyzed using molecular and morphological evidence. Phylogenetic analyses based on the rbcL gene sequences grouped all populations in a large clade including our S. arcuata specimens and others from several regions. Sheathia arcuata represents a species complex with a high sequence divergence and several smaller clades. Samples from India and Nepal were grouped in three distinct clades with high support and representing new cryptic species: a clade formed by two samples from India, which was named Sheathia assamica sp. nov.; one sample from India and one from Nepal formed another clade, named Sheathia indonepalensis sp. nov.; two samples from Nepal grouped with sequences from Hawaii and Indonesia (only 'Chantransia' stages) and gametophytes from Taiwan, named Sheathia dispersa sp. nov. Morphological characters of the specimens from these three species overlap one another and with the general circumscription of S. arcuata, which lacks the heterocortication (presence of bulbous cells in the cortical filaments) present in other species of the genus Sheathia. Although the region sampled is relatively restricted, the genetic diversity among specimens of these three groups was high and not closely related in the phylogenetic relationship with the other clades of S. arcuata. These data corroborate information from other groups of organisms (e.g., land and aquatic plants) that indicates this region (Eastern Himalaya) as a hotspot of biodiversity.

• Journal of Microbiology and Biotechnology
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• v.20 no.7
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• pp.1128-1133
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• 2010

The diversity and abundance of ammonia-oxidizing bacteria (AOB) in activated sludge were compared using PCR-DGGE and real-time PCR assays. Activated sludge samples were collected from five different types of wastewater treatment plants (WWTPs) mainly treating textile, paper, food, and livestock wastewater or domestic sewage. The composition of total bacteria determined by PCR-DGGE was highly diverse between the samples, whereas the community of AOB was similar across all the investigated activated sludge. Total bacterial numbers and AOB numbers in the aerated mixed liquor were in the range of $1.8{\times}10^{10}$ to $3.8{\times}10^{12}$ and $1.7{\times}10^6$ to $2.7{\times}10^{10}$ copies/l, respectively. Activated sludge from livestock, textile, and sewage treating WWTPs contained relatively high amoA gene copies (more than $10^5$ copies/l), whereas activated sludge from food and paper WWTPs revealed a low number of the amoA gene (less than $10^3$ copies/l). The value of the amoA gene copy effectively showed the difference in composition of bacteria in different activated sludge samples and this was better than the measurement with the AOB 16S rRNA or total 16S rRNA gene. These results suggest that the quantification of the amoA gene can help monitor AOB and ammonia oxidation in WWTPs.