• Journal of Ecology and Environment
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• v.36 no.3
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• pp.159-166
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• 2013

Oryzias latipes and Oryzias sinensis are indigenous species found in Japan, China, and other East Asian countries, including Korea. Based on morphological differences, the species have been classified distinctly. However, the range of morphological characters such as the number of gill rakers, vertebrae, and spots on the lateral body overlaps and is too vague for clear identification, so their classification based on their morphological characteristics remains uncertain. In this study, the mitochondrial cytochrome oxidase subunit I (COI) gene, which is used for DNA barcoding, was applied to clarify interspecific variation of O. latipes and O. sinensis. Intraspecific genetic diversity was calculated to identify correlations with geographic distributions. We studied two species collected from 55 locations in Korea. All individuals carried a 679-base pair gene without deletion or insertion. Between species, 525 base pairs of the gene were shared. The Kimura two parameter (K2P) distance of O. latipes and O. sinensis was 0.41% and 1.39%, respectively. Mean divergence within genera was 23.5%. Therefore, the species were clearly different. The distance between O. latipes and O. sinensis was 14.0%, which is the closest within genera. Interestingly O. latipes from the Japanese and Korean group represented 16.5% distant. These results were derived from geohistorical and anthropogenic environmental factors. The O. latipes haplotypes were joined in only one group, but O. sinensis was divided into two groups, one is found in the Han River and upper Geum River watershed; the other is found in the remaining South Korean watersheds. Further studies will address the causes for geographic speciation of O. sinensis haplotypes.

• Development and Reproduction
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• v.23 no.1
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• pp.11-19
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• 2019

The study was conducted to investigate the effects of alpha-linolenic acid (ALA) combined with bovine serum albumin (BSA) or methyl-beta-cyclodextrin (MBCD) on plasma and acrosomal membrane damages, mitochondrial activity, morphological abnormality, motility, and oxidative stress in frozen-thawed boar sperm. In previous our study, 3 ng/mL ALA had been shown protective effect during freezing process of boar sperm. Therefore, we used 3 ng/mL ALA in present study and ALA was combined with same molar ratio of BSA or MBCD (ALA+BSA and ALA+MBCD, respectively). To confirm the effect of two carrier proteins, same volume of BSA and MBCD without ALA were added during cryopreservation. Membrane damage, mitochondrial activity, reactive oxygen species (ROS) and lipid peroxidation (LPO) levels were measured using flow cytometry, and movement of sperm tail as motility parameter and morphological abnormality were observed under light microscope. In results, all of sperm parameters were enhanced by ALA combined with BSA or MBCD compared to control groups (p<0.05). Mitochondrial activity, morphological abnormality, ROS and LPO levels in ALA+BSA or MBCD groups were no significant difference compared with ALA, BSA and MBCD treatment groups. On the other hand, plasma and acrosomal membrane intact, and sperm motility in ALA+MBCD group were higher than single treatment groups (p<0.05), whereas ALA+BSA did not differ. Our findings indicate that carrier proteins such as BSA and MBCD could improve the effect of ALA during cryopreservation of boar sperm, and treatment of ALA with carrier proteins enhance membrane integrity, mitochondrial activity through reduction of ROS-induced LPO.

• Journal of Bio-Environment Control
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• v.32 no.3
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• pp.205-209
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• 2023

Mechanical stimulation induce the morphological changes in plants. In this study, we investigated the growth changes of tomato seedlings applicated to mechanical stimulation. The brushing treatment was used for mechanical stimulation. The brushing treatment interval was 2 hr using transfer device attached acrylic film from 10 days after sowing. Growth parameter of tomato seedlings were measured 3-day intervals to investigate the growth changes during brushing treatment. The plant height and leaf area were decreased in brushing treatment than the control, and the fresh and dry weights of shoot didn't have significant difference in the control and brushing treatment. The total root length and root surface area were increased in brushing treatment compared than the control, and root volume has no significant difference in the control and brushing treatment. In conclusion, these results suggest that the application of brushing treatment on tomato seedling make shorten plant height and well-development root morphological characteristics.

• Fisheries and Aquatic Sciences
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• v.27 no.2
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• pp.87-99
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• 2024

Global climate change, followed by an increase in anthropogenic activities in aquatic ecosystems, and species invasions, has resulted in a decline in aquatic organism biodiversity. The Batanghari River, Sumatra's longest river, is polluted by mercury-containing illegal gold mining waste (PETI), industrial pollution, and domestic waste. Several studies have provided evidence suggesting a decline in fish biodiversity within the Batanghari River. However, a comprehensive evaluation of the present status of biodiversity in this river is currently lacking. The species under investigation were identified through various molecular-based identification methods, as well as morphological identification, which involved the use of neighbor-joining (NJ) trees. All collected specimens were initially identified using morphological techniques and subsequently confirmed with molecular barcoding analysis. Morphological and DNA barcoding identification categorized all specimens (1,692) into 36 species, 30 genera and 16 families, representing five orders. A total of 36 DNA barcodes were generated from 30 genera using a 650-bp-long fragment of the mitochondrial cytochrome oxidase subunit I (COI) gene. Based on the Kimura two-parameter model (K2P), The minimum and maximum genetic divergences based on K2P distance were 0.003 and 0.331, respectively, and the average genetic divergence within genera, families, and orders was 0.05, 0.12, 0.16 respectively. In addition, the average interspecific distance was approximately 2.17 times higher than the mean intraspecific distance. Our results showed that the COI barcode enabled accurate fish species identification in the Batanghari River. Furthermore, the present work will establish a comprehensive DNA barcode library for freshwater fishes along Batanghari River and be significantly useful in future efforts to monitor, conserve, and manage fisheries in Indonesia.

• Journal of the Microelectronics and Packaging Society
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• v.11 no.3 s.32
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• pp.47-53
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• 2004

Eutectic Au-20Sn(compositions are all in weight percent unless specified otherwise) solder alloys were soldered on the Ni substrate with various time and temperature. The composition, phase identification and morphology of intermetallic compounds(IMC) at the interface were examined using Scanning Electron Microscopy(SEM). There were two types of IMCs, $(Au,Ni)_3Sn_2$ and $(Au,Ni)_3Sn$ at the interface. The transition in morphology of $(Au,Ni)_3Sn_2$ has been observed at $300{\~}400^{\circ}C$. The morphology transition of $(Au,Ni)_3Sn_2$ is due to the decrease of enthalpy of formation of $(Au,Ni)_3Sn_2$ phase and has been explained well by Jackson's parameter with temperature. Because the number of diffusion channel is different at each soldering temperature, IMC thickness is nearly same at all temperature.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.944-958
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• 2011

Soil hydraulic properties such as hydraulic conductivity or water retention which are costly to measure can be indirectly generated by soil pedotransfer function (PTF) using easily obtainable soil data. The field soil structure description which is routinely recorded could also be used in PTF as an input to reduce the uncertainty. The purposes of this study were to use qualitative morphological soil structure descriptions and soil structural index into PTF and to evaluate their contribution in the prediction of soil hydraulic properties. We transformed categorical morphological descriptions of soil structure into quantitative values using categorical principal component analysis (CATPCA). This approach was tested with a large data set from the US National Pedon Characterization database with the aid of a categorical regression tree analysis. Six different PTFs were used to predict the saturated hydraulic conductivity and those results were averaged to quantify the uncertainty. Quantified morphological description was successively used in multiple linear regression approach to predict the averaged ensemble saturated conductivity. The selected stepwise regression model with only the transformed morphological variables and structural index as predictors predicted the $K_{sat}$ with $r^2$ = 0.48 (p = 0.018), indicating the feasibility of CATPCA approach. In a regression tree analysis, soil structure index and soil texture turned out to be important factors in the prediction of the hydraulic properties. Among structural descriptions size class turned out to be an important grouping parameter in the regression tree. Bulk density, clay content, W33 and structural index explained clusters selected by a two step clustering technique, implying the morphologically described soil structural features are closely related to soil physical as well as hydraulic properties. Although this study provided relatively new method which related soil structure description to soil structure index, the same approach should be tested using a datasets containing the actual measurement of hydraulic properties. More insight on the predictive power of soil structure index to estimate hydraulic properties would be achieved by considering measured the saturated hydraulic conductivity and the soil water retention.

• Proceedings of the Acoustical Society of Korea Conference
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• 1994.06c
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• pp.364-367
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• 1994

In this paper, we carried out some experiments on the Korean vowel recognition using the fractal dimension of the speech signals. We chose the Mincowski-Bouligand dimensioni as the fractal dimension, and computed it using the morphological covering method. For our experiments, we used both the fractal dimension and the LPC cepstrum which is conventionally known to be one of the best parameters for speech recognition, and examined the usefulness of the fractal dimension. From the vowel recognition experiments under various consonant contexts, we achieved the vowel recognition error rats of 5.6% and 3.2% for the case with only LPC cepstrum and that with both LPC cepstrum and the fractal dimension, respectively. The results indicate that the incorporation of the fractal dimension with LPC cepstrum gies more than 40% reduction in recognition errors, and indicates that the fractal dimension is a useful feature parameter for speech recognition.

• Journal of Powder Materials
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• v.18 no.1
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• pp.73-77
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• 2011

$Y(OH)_3$ nanowires were synthesized by a hydrothermal reaction of metallic Y with aqueous solution of LiOH. The morphology and the size of the nanowires changed with varying the volume of the LiOH solution inside the autoclave. $Y(OH)_3$ nanowires transformed to $Y_2O_3$ by a subsequent heat-treatment without morphological change. By a proper control of hydrothermal reaction parameter and heat-treatment, the yield of pure $Y_2O_3$ nanowires up to 97% was attained.

• Microbiology and Biotechnology Letters
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• v.19 no.6
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• pp.624-630
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• 1991

Sixty five phenol degrading bacteria were isolated from soil and identified. Sirnility values calculated on the basis of total 46 morphological, biochemical and physiological characteristics of the isolated strains. 65 isolates were divided into 6 clusters at the 70% simility lavei, The dominant organisms were belonged to Azotobacter, Pseudomonas and Flavobactwium.

• Tribology and Lubricants
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• v.12 no.3
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• pp.72-78
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• 1996

This paper was undertaken to analyze the morphology of wear debris generated from lubricated moving machine surfaces by image processing. The lubricati, ng wear test was performed under different experimental conditions using the wear test device made in our laboratory and wear test specimen of the pin on disk type wear rubbed in paraffme series base oil, by varying applied load, sliding distance. The four parameters (50% volumetric diameter, aspect, roundness and reflectivity) to describe the morphology have been developed and outlined in the paper. A system using such techniques promises to obviate the need for subjective, human interpretation of particle morphology in machine condition monitoring, thus to overcome many of the difficulties with current methods and to facilitate wider use of wear particle analysis in machine condition monitoring.